Low-dose metformin targets the lysosomal AMPK pathway through PEN2.

Metformin, the most prescribed antidiabetic medicine, has shown other benefits such as anti-ageing and anticancer effects1-4. For clinical doses of metformin, AMP-activated protein kinase (AMPK) has a major role in its mechanism of action4,5; however, the direct molecular target of metformin remains unknown. Here we show that clinically relevant concentrations of metformin inhibit the lysosomal proton pump v-ATPase, which is a central node for AMPK activation following glucose starvation6. We synthesize a photoactive metformin probe and identify PEN2, a subunit of γ-secretase7, as a binding partner of metformin with a dissociation constant at micromolar levels. Metformin-bound PEN2 forms a complex with ATP6AP1, a subunit of the v-ATPase8, which leads to the inhibition of v-ATPase and the activation of AMPK without effects on cellular AMP levels. Knockout of PEN2 or re-introduction of a PEN2 mutant that does not bind ATP6AP1 blunts AMPK activation. In vivo, liver-specific knockout of Pen2 abolishes metformin-mediated reduction of hepatic fat content, whereas intestine-specific knockout of Pen2 impairs its glucose-lowering effects. Furthermore, knockdown of pen-2 in Caenorhabditis elegans abrogates metformin-induced extension of lifespan. Together, these findings reveal that metformin binds PEN2 and initiates a signalling route that intersects, through ATP6AP1, the lysosomal glucose-sensing pathway for AMPK activation. This ensures that metformin exerts its therapeutic benefits in patients without substantial adverse effects.

Omics studies of DNA G-/C-quadruplexes in plants.

Genome-wide studies of DNA G- and C-quadruplexes (G4s and i-motifs, respectively) can boost the pace of progress towards a comprehensive understanding of their biological implications and practical applications in plants. We summarize the current state of knowledge about omics studies in order to highlight the current challenges and propose future directions to take studies of plant quadruplexes to the next step.

R-loops act as regulatory switches modulating transcription of COLD-responsive genes in rice.

COLD is a major naturally occurring stress that usually causes complex symptoms and severe yield loss in crops. R-loops function in various cellular processes, including development and stress responses, in plants. However, how R-loops function in COLD responses is largely unknown in COLD susceptible crops like rice (Oryza sativa L.). We conducted DRIP-Seq along with other omics data (RNA-Seq, DNase-Seq and ChIP-Seq) in rice with or without COLD treatment. COLD treatment caused R-loop reprogramming across the genome. COLD-biased R-loops had higher GC content and novel motifs for the binding of distinct transcription factors (TFs). Moreover, R-loops can directly/indirectly modulate the transcription of a subset of COLD-responsive genes, which can be mediated by R-loop overlapping TF-centered or cis-regulatory element-related regulatory networks and lncRNAs, accounting for c. 60% of COLD-induced expression of differential genes in rice, which is different from the findings in Arabidopsis. We validated two R-loop loci with contrasting (negative/positive) roles in the regulation of two individual COLD-responsive gene expression, as potential targets for enhanced COLD resistance. Our study provides detailed evidence showing functions of R-loop reprogramming during COLD responses and provides some potential R-loop loci for genetic and epigenetic manipulation toward breeding of rice varieties with enhanced COLD tolerance.

Genomic variations combined with epigenetic modifications rewire open chromatin in rice.

Cis-regulatory elements (CREs) fine-tune gene transcription in eukaryotes. CREs with sequence variations play vital roles in driving plant or crop domestication. However, how global sequence and structural variations (SVs) are responsible for multilevel changes between indica and japonica rice (Oryza sativa) is still not fully elucidated. To address this, we conducted multiomic studies using MNase hypersensitivity sequencing (MH-seq) in combination with RNA sequencing (RNA-seq), chromatin immunoprecipitation sequencing (ChIP-seq), and bisulfite sequencing (BS-seq) between the japonica rice variety Nipponbare (NIP) and indica rice variety 93-11. We found that differential MNase hypersensitive sites (MHSs) exhibited some distinct intrinsic genomic sequence features between NIP and 93-11. Notably, through MHS-genome-wide association studies (GWAS) integration, we found that key sequence variations may be associated with differences of agronomic traits between NIP and 93-11, which is partly achieved by MHSs harboring CREs. In addition, SV-derived differential MHSs caused by transposable element (TE) insertion, especially by noncommon TEs among rice varieties, were associated with genes with distinct functions, indicating that TE-driven gene neo- or subfunctionalization is mediated by changes of chromatin openness. This study thus provides insights into how sequence and genomic SVs control agronomic traits of NIP and 93-11; it also provides genome-editing targets for molecular breeding aiming at improving favorable agronomic properties.

Modification of the electrokinetic motion of microalgae through light illumination for viability assessment.

The viability detection of microalgae with the electrokinetic (EK) technique shows vast applications in the biology and maritime industry. However, due to the slight variations in the EK properties between alive and dead microalgae cells, the accuracy and practicability of this technique is limited. In this paper, the light illumination pretreatment was conducted to modify the EK velocity of microalgae for enhancing the EK difference. The effects of the illumination time and light color on the EK velocities of Chlorella vulgaris and Isochrysis galbana were systematically measured, and the EK differences between alive and dead cells were calculated and compared. The results indicate that under light illumination, the photosynthesis of the alive cells leads to the amplification of the zeta potential, leading toward increase in the EK difference along with the illumination time. By using light with different color spectra to treat the microalgae, it was found that the EK difference changes with the light color according to the following order: white light > red light > blue light > green light. The difference in EK potential with exposure to white light treatment surpasses over 10-fold in comparison to those without such treatment. The light pretreatment technique, as illustrated in this study, offers an advantageous strategy to enhance the EK difference between living and dead cells, proving beneficial in the field of microalgae biotechnology.

Causal relationship between lipid-lowering drugs and ovarian cancer, cervical cancer: a drug target mendelian randomization study.

BACKGROUND: The causal impact of lipid-lowering drugs on ovarian cancer (OC) and cervical cancer (CC) has received considerable attention, but its causal relationship is still a subject of debate. Hence, the objective of this study is to evaluate the impact of lipid-lowering medications on the occurrence risk of OC and CC through Mendelian randomization (MR) analysis of drug targets. METHODS: This investigation concentrated on the primary targets of lipid-lowering medications, specifically, 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) and proprotein convertase kexin 9 (PCSK9). Genetic variations associated with HMGCR and PCSK9 were derived from published genome-wide association study (GWAS) findings to serve as substitutes for HMGCR and PCSK9 inhibitors. Employing a MR approach, an analysis was conducted to scrutinize the impact of inhibitors targeting HMGCR and PCSK9 on the occurrence of OC and CC. Coronary heart disease (CHD) risk was utilized as a positive control, and the primary outcomes encompassed OC and CC. RESULTS: The findings of the study suggest a notable elevation in the risk of OC among patients treated with HMGCR inhibitors (OR [95%CI] = 1.815 [1.316, 2.315], p = 0.019). In contrast, no significant correlation was observed between PCSK9 inhibitors and the occurrence of OC. Additionally, the analysis did not reveal any noteworthy connection between HMGCR inhibitors, PCSK9 inhibitors, and CC. CONCLUSION: HMGCR inhibitors significantly elevate the risk of OC in patients, but their mechanism needs further investigation, and no influence of PCSK9 inhibitors on OC has been observed. There is no significant relationship between HMGCR inhibitors, PCSK9 inhibitors, and CC.

Analysis of characteristic and postexposure practices of occupational blood and body fluid exposures among health care workers in Chinese tertiary hospitals: a retrospective ten-year study.

BACKGROUND: Occupational blood and body fluid exposure (OBEs) is a highly concerning global health problem in health facilities. Improper or inadequate post-exposure practices increase the risk of infection with bloodborne pathogens. Understanding risk factors for OBEs and evaluating the post-exposure practices will contribute to healthcare workers' (HCWs) well-being. METHODS: This study retrospectively synthesized and reviewed the 10-year data (from 2010 to 2020) on OBEs in a tertiary teaching hospital. RESULTS: A total of 519 HCWs have reported OBEs, increasing yearly from 2010 to 2020. Of these, most were nurses (247 [47.2%]), female (390 [75.1%]), at 23-27 years old (207 [39.9%]). The hepatitis B was the primary bloodborne pathogen exposed to HCWs, with 285 (54.9%) cases, internal medicine was the main exposure site (161 [31.0%]), and sharp injury was the main exposure route (439 [84.6%]). Data analysis shows that there are significant differences between exposure route, exposed pathogens, and exposure site among the different occupational categories (X2 = 14.5, 43.7, 94.3, all P < 0.001). 3.3% of HCWs did not take any post-exposure practices. For percutaneous exposure, 4.7% did not rinse the wound, 3.3% did not squeeze out the wound, and 2.3% did not disinfect the wound. In the case of mucosal exposure, 90.4% clean the exposure area immediately. CONCLUSIONS: The data from the past decade underscores the seriousness of current situation of OBEs in Chinese tertiary hospital, particularly among young HCWs, and with hepatitis B as the predominant blood-borne pathogen. This study also identifies HCWs may take incorrect post-exposure practices. It's crucial in the future to discuss the effectiveness of main groups targeted for focused specialty-specific guidance for the prevention of such accidents, meanwhile, to include blood-borne disease immunity testing in mandatory health check-ups. Additionally, focus on optimizing post-exposure practices, offering significant steps toward prevention of such incidents and reducing infection risks should also be considered in future studies.

Impacts of cardiometabolic risk factors and alcohol consumption on all-cause mortality among MASLD and its subgroups.

BACKGROUND AND AIMS: Recently, metabolic dysfunction-associated steatotic liver disease (MASLD) has been introduced. However, research on this new nomenclature and definition remains limited. This study aims to assess the impact of cardiometabolic risk factors and alcohol consumption on all-cause mortality in MASLD and its subgroups. METHODS AND RESULTS: We included 2408 participants with MASLD in NHANES III and their linked mortality through 2019. MASLD patients were divided into two groups based on alcohol consumption: Pure MASLD and MetALD. The Cox proportional hazard model was used to assess the association between factors and all-cause mortality. During the median 26.0-year follow-up, there were 1040 deaths. The multivariable Cox regression analysis revealed a significant increase of over two-fold in the all-cause mortality rate among patients with four or more cardiometabolic risk factors compared to those with only one. When focusing on each component of cardiometabolic risk factors individually, only diabetes and hypertension were significantly associated with all-cause mortality (p < 0.05). In a subgroup analysis, each additional cardiometabolic factor was linked to an increase in all-cause mortality in both pure MASLD (hazard ratio 1.16; 95% CI 1.06-1.28; p = 0.002) and MetALD (HR 1.77; 95% CI 1.26-2.49; p = 0.001). Notably, an elevation in alcohol consumption was significantly associated with an increase in all-cause mortality rate only in the MetALD (p < 0.001). CONCLUSIONS: This study found that the presence of diabetes or hypertension was significantly associated with all-cause mortality. We also explored the different impacts of these factors and alcohol consumption within MASLD subgroups.

Whole genome resequencing reveals significant genetic differentiation between Exserohilum turcicum populations from maize and sorghum and candidate effector genes related to host specificity (Retracted).

After the manuscript was accepted, inconsistencies in the analyses were detected. These inconsistencies affected the general conclusion of the manuscript. This article was retracted on 27 March 2024.Exserohilum turcicum is a devastating fungal pathogen that infects both maize and sorghum, leading to severe leaf diseases of the two crops. According to host specificity, pathogenic isolates of E. turcicum are divided into two formae speciales, namely E. turcicum f. sp. zeae and E. turcicum f. sp. sorghi. To date, the molecular mechanism underlying the host specificity of E. turcicum is marginally known. In this study, the whole genomes of 60 E. turcicum isolates collected from both maize and sorghum were resequenced, which enabled identification of 147,847 high-quality SNPs in total. Based on the SNPs, all isolates were clustered into four genetic groups that had a close relationship with host source. This observation was validated by the result of principal component analysis. The analysis of population structure revealed that there was obvious genetic differentiation between maize and sorghum host populations. Further analysis showed that 5,431 SNPs, including 612 nonsynonymous SNPs, were completely co-segregated with host source. These nonsynonymous SNPs were located in 539 genes in which 18 genes were predicted to encode secretory proteins, including six putative effector genes. The sequence polymorphism analysis of the six effector genes in 60 isolates indicated that these genes were perfectly co-segregated with host source. All SNVs in the coding regions of these genes were non-synonymous substitutions, suggesting that these genes were subject to strong positive selection pressure. These findings provide new insights into the molecular basis of host specificity in E. turcicum.

The effect of a mindfulness and motivational interviewing-oriented physical-psychological integrative intervention for community-dwelling spinal cord injury survivors: a mixed-methods randomized controlled trial.

OBJECTIVE: To evaluate the feasibility, acceptability, and efficacy of a mindfulness and motivational interviewing-oriented physical-psychological integrated intervention in community-dwelling spinal cord injury (SCI) survivors. DESIGN: A mixed-methods randomized controlled trial. SETTING: Local organizations of handicapped in Hong Kong. PARTICIPANTS: Community-dwelling adults with SCI (N = 72). INTERVENTIONS: Participants in the intervention group (n = 36) received video-guided exercise for daily practice and online group psychological (mindfulness and motivational interviewing-oriented) weekly sessions for eight weeks. Participants in the control group (n = 36) received an eight-week online group didactic education on lifestyle discussions and general health suggestions. MAIN OUTCOMES MEASURES: Primary outcomes included quality of life, physical activity, depression, and chronic pain. Secondary outcomes included exercise self-efficacy and mindfulness. Outcomes were measured at baseline, post-intervention, and three-month follow-up. Focus-group interviews were conducted post-intervention. RESULTS: The recruitment, retention, and adherence rates were 84.7%, 100%, and 98.6%, respectively. The intervention showed significant positive effects on preventing declines in quality of life at three-month follow-up [Cohen's d = 0.70 (0.22, 1.18)]. Positive trends manifested in physical activity, depression, chronic pain, and exercise self-efficacy. Three qualitative categories were identified: subjective improvements in exercise, physical, and social well-being; perceived changes in mindfulness and mental well-being; and intervention facilitators and barriers. CONCLUSIONS: The mindfulness and motivational interviewing-oriented physical-psychological integrated intervention is feasible and acceptable. The significant prolonged effect in maintaining quality of life and positive impacts on physical and psychosocial well-being indicate its value to address major health challenges of community-dwelling SCI survivors.

Bilin-dependent regulation of chlorophyll biosynthesis by GUN4.

Biosyntheses of chlorophyll and heme in oxygenic phototrophs share a common trunk pathway that diverges with insertion of magnesium or iron into the last common intermediate, protoporphyrin IX. Since both tetrapyrroles are pro-oxidants, it is essential that their metabolism is tightly regulated. Here, we establish that heme-derived linear tetrapyrroles (bilins) function to stimulate the enzymatic activity of magnesium chelatase (MgCh) via their interaction with GENOMES UNCOUPLED 4 (GUN4) in the model green alga Chlamydomonas reinhardtii A key tetrapyrrole-binding component of MgCh found in all oxygenic photosynthetic species, CrGUN4, also stabilizes the bilin-dependent accumulation of protoporphyrin IX-binding CrCHLH1 subunit of MgCh in light-grown C. reinhardtii cells by preventing its photooxidative inactivation. Exogenous application of biliverdin IXα reverses the loss of CrCHLH1 in the bilin-deficient heme oxygenase (hmox1) mutant, but not in the gun4 mutant. We propose that these dual regulatory roles of GUN4:bilin complexes are responsible for the retention of bilin biosynthesis in all photosynthetic eukaryotes, which sustains chlorophyll biosynthesis in an illuminated oxic environment.

The health benefits of dietary polyphenols on pediatric intestinal diseases: Mechanism of action, clinical evidence and future research progress.

Pediatric intestinal development is immature, vulnerable to external influences and produce a variety of intestinal diseases. At present, breakthroughs have been made in the treatment of pediatric intestinal diseases, but there are still many challenges, such as toxic side effects, drug resistance, and the lack of more effective treatments and specific drugs. In recent years, dietary polyphenols derived from plants have become a research hotspot in the treatment of pediatric intestinal diseases due to their outstanding pharmacological activities such, as anti-inflammatory, antibacterial, antioxidant and regulation of intestinal flora. This article reviewed the mechanism of action and clinical evidence of dietary polyphenols in the treatment of pediatric intestinal diseases, and discussed the influence of physiological characteristics of children on the efficacy of polyphenols, and finally prospected the new dosage forms of polyphenols in pediatrics.

Interfacial galvanic replacement strategy for Pd-doped NiFe MOF nanosheets with highly efficient dopamine detection.

An interfacial galvanic replacement strategy to controllable synthesize palladium nanoparticles (Pd NPs)-modified NiFe MOF nanocomposite on nickel foam, which served as an efficient sensing platform for quantitative determination of dopamine (DA). Pd NPs grown in situ on the nanosheets of NiFe MOF via self-driven galvanic replacement reaction (GRR) and well uniform distribution was achieved. This method effectively reduced the aggregation of metallic nanoparticles and significantly promoted the electron transfer rate during the electrochemical process, leading to improved electrocatalytic activity for DA oxidation. Remarkably, the precisely constructed biosensor achieved a low detection limit (LOD) of 0.068 µM and recovery of 94.1% (RSD 6.7%, N = 3) for simulated real sample detection and also exhibited superior selectivity and stability. The results confirmed that the as-fabricated Pd-NiFe/NF composite electrode could realize the quantitative determination of DA and showed promising prospects in real sample biosensing.

Early blood immune molecular alterations in cynomolgus monkeys with a PSEN1 mutation causing familial Alzheimer's disease.

INTRODUCTION: More robust non-human primate models of Alzheimer's disease (AD) will provide new opportunities to better understand the pathogenesis and progression of AD. METHODS: We designed a CRISPR/Cas9 system to achieve precise genomic deletion of exon 9 in cynomolgus monkeys using two guide RNAs targeting the 3' and 5' intron sequences of PSEN1 exon 9. We performed biochemical, transcriptome, proteome, and biomarker analyses to characterize the cellular and molecular dysregulations of this non-human primate model. RESULTS: We observed early changes of AD-related pathological proteins (cerebrospinal fluid Aß42 and phosphorylated tau) in PSEN1 mutant (ie, PSEN1-ΔE9) monkeys. Blood transcriptome and proteome profiling revealed early changes in inflammatory and immune molecules in juvenile PSEN1-ΔE9 cynomolgus monkeys. DISCUSSION: PSEN1 mutant cynomolgus monkeys recapitulate AD-related pathological protein changes, and reveal early alterations in blood immune signaling. Thus, this model might mimic AD-associated pathogenesis and has potential utility for developing early diagnostic and therapeutic interventions. HIGHLIGHTS: A dual-guide CRISPR/Cas9 system successfully mimics AD PSEN1-ΔE9 mutation by genomic excision of exon 9. PSEN1 mutant cynomolgus monkey-derived fibroblasts exhibit disrupted PSEN1 endoproteolysis and increased Aß secretion. Blood transcriptome and proteome profiling implicate early inflammatory and immune molecular dysregulation in juvenile PSEN1 mutant cynomolgus monkeys. Cerebrospinal fluid from juvenile PSEN1 mutant monkeys recapitulates early changes of AD-related pathological proteins (increased Aß42 and phosphorylated tau).

"Am I different?" Coping and mental health among teenagers with adolescent idiopathic scoliosis: A qualitative study.

PURPOSE: To explore the stressors, coping strategies, and mental health of adolescents diagnosed with idiopathic scoliosis. DESIGN AND METHODS: This study adopted a descriptive qualitative study design. Twelve participants were recruited from a local non-government organization in Hong Kong. Semi-structured interviews were conducted to collect data. Verbatim transcriptions of interviews were coded and analyzed using thematic analysis. The guideline of the Consolidated Criteria for Reporting Qualitative Studies was used to report the findings. RESULTS: Five themes were identified: "Disease- and treatment-induced changes and stressors", "Cognitive assessment and personal perceptions", "Behavioral and emotional coping strategies", "Social interactions and social support", and "Deteriorating or thriving in psychological development and well-being". CONCLUSIONS: Adolescents with idiopathic scoliosis experienced a variety of physical and psychological stressors. It is imperative to prioritize efforts to promote adaptive coping and activate social support systems to achieve better outcomes in this population. PRACTICAL IMPLICATIONS: Healthcare providers should aim to comprehend the experiences of adolescents with idiopathic scoliosis for improved clinical interactions and holistic care. Future research should prioritize coping-based interventions, to enhance adaptive coping behaviors and the well-being of this population.

Pyridazine-Promoted Construction of Vinylene-Linked Covalent Organic Frameworks with Exceptional Capability of Stepwise Water Harvesting.

In this study, we successfully developed two novel vinylene-linked covalent organic frameworks (COFs) using 2-connected 3,6-dimethylpyridazine through Knoevenagel condensation. These COFs featured finely tailored micro-/nano-scale pore sizes, high surface areas and stable non-polar vinylene linkages. Finely resolved powder X-ray diffraction patterns demonstrated highly crystalline structures with a hexagonal lattice in the AA layer stacking. The resulting one-dimensional channels possess strong hydrogen-bond accepting sites arising from the decorated cis-azo/azine units with two pairs of fully exposed lone pair electrons, endowing the as-prepared COFs with exceptional water absorption properties. The g-DZPH-COF exhibited successive steep water uptake steps starting from low relative pressures (P/PSTA = 0.1), with the remarkable water uptake capacity of 0.26 g/g at P/PSTA = 0.2 (25°C), which is the optimal value recorded among the reported COFs. Dynamic vapour sorption measurements revealed the fast kinetics of these COFs, even in the cluster formation process. Water uptake and release cycling tests demonstrated their outstanding hydrolytic stability, durability, and adsorption-desorption retention ability.

Mesoporous Vinylene-Linked Covalent Organic Frameworks with Heteroatom-Tuned Crystallinity and Photocatalytic Behaviors.

Owing to its prominent π-delocalization and stability, vinylene linkage holds great merits in the construction of covalent organic frameworks (COFs) with promising semiconducting properties. However, carbon-carbon double bond formation reaction always exhibits relatively low reversibility, unfavorable for the formation of high crystalline frameworks through self-error correction and assembling processes. In this work, we report a heteroatom-tuned strategy to build up a series of two-dimensional (2D) vinylene-linked COFs by Knoevenagel condensation of an electron-deficient methylthiazolyl-based monomer with different triformyl substituted (hetero-)aromatic derivatives. The resulting COFs show high-quality periodic mesoporous structures with high surface areas. Embedding heteroatoms into the backbones enables significantly improving their crystallinity, and finely tailoring their semiconducting structures. Upon visible light stimulation, one of the as-prepared COFs with donor-π-acceptor structure could deliver a nearly seven-fold increase in the catalytic activity of hydrogen generation as compared with the other two. Meanwhile, in combination with high crystallinity and the matched conduction band energy level, such kind of COFs can be able to selectively generate singlet oxygen and superoxide radicals in a high ratio of up to 30:1, allowing for catalyzing aerobic thioanisole oxidation in distinctly tunable activities through the substituent electronic effect of the substrates.

Liquid Crystal Assembly for Ultra-dissymmetric Circularly Polarized Luminescence and Beyond.

Circularly polarized luminescence (CPL) is attracting much interest because it can carry extensive optical information. CPL shows left- or right-handedness and can be regarded as part of high-level visual perception to supply an extra dimension of information with regard to regular light. A key to meeting the needs for practical applications is to develop the emerging field of ultra-dissymmetric CPL. Chiral liquid crystal (LC) assemblies─otherwise referred to as cholesteric liquid crystals (CLCs)─are essentially organized helical superstructures with a highly ordered one-dimensional orientation, and distinctly superior to regular helical supramolecules. CLCs can achieve a perfect equilibrium of molecular short-range interaction and long-range orientational order, enabling molecule-scale chirality on a helical pitch and observable scale. LC assembly could be an ideal strategy for amplifying chirality, making it accessible to ultra-dissymmetric CPL. Herein, we focused on some basic but important issues regarding CPL: (i) How can CPL be created from chiral dyes? (ii) Is the chirality of luminescent dyes an essential factor for the generation of CPL? That is, can all chiral dyes emit CPL and vice versa? (iii) How can CPL be transferred within intermolecular systems, and what principles of CPL transmission should be followed? Given these queries and our work, in this Perspective we discuss the generation, transmission, and modulation of CPL with chiral LC assembly, aiming to design and build up novel chiroptical materials. Recent applications of CPL-active LC microstructures in three-dimensional displays, circularly polarized lasers, and asymmetric catalysis are also discussed.

Hexatopic Vertex-Directed Approach to Vinylene-Linked Covalent Organic Frameworks with Heteroporous Topologies.

A D3h-symmetric hexatopic monomer was first prepared by attaching the three-fold ditopic moiety 2,6-dimethylpyridine to the meta-positions of a phenyl ring. It was further condensed at its six pyridylmethyl carbons with linear ditopic aromatic dialdehydes, resulting in two vinylene-linked COFs with heteroporous topologies, as revealed by powder X-ray diffraction (PXRD), nitrogen sorption, and pore-size distribution analyses, as well as transmission electron microscopy (TEM) image. The linear- and cross-conjugations, respectively, arising from the 2,6-linked pyridines and meta-linked phenylenes in the hexatopic nodes rendered the resultant COFs with well-patterned π-delocalization, allowing for efficiently catalyzing the bromination of aromatic derivatives with the pore-size-dependent conversion yields and regioselectivity under the irradiation of green light.

High-Performance Integrated Iontronic Circuits Based on Single Nano/Microchannels.

Recently, artificial channel-based ionic diodes and transistors are extensively studied to mimic biological systems. Most of them are constructed vertically and are challenging to be further integrated. Several examples of ionic circuits with horizontal ionic diodes are reported. However, they generally require nanoscale channel sizes to meet the demand for ion-selectivity, resulting in low current output and restricting potential applications. In this paper, a novel ionic diode is developed based on multiple-layer polyelectrolyte nanochannel network membranes. Both bipolar and unipolar ionic diodes can be achieved by simply switching the modification solution. Ionic diodes with a high rectification ratio of ≈226 are achieved in single channels with the largest channel size of 2.5 µm. This design can significantly reduce the channel size requirement and improve the output current level of ionic devices. The high-performance ionic diode with a horizontal structure enables the integration of advanced iontronic circuits. Ionic transistors, logic gates, and rectifiers are fabricated on a single chip and demonstrated for current rectification. Furthermore, the excellent current rectification ratio and the high output current of the on-chip ionic devices highlight the promise of the ionic diode as a component of complex iontronic systems for practical applications.