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1.
Proc Natl Acad Sci U S A ; 120(38): e2310163120, 2023 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-37703282

RESUMO

Callus is a reprogrammed cell mass involved in plant regeneration and gene transformation in crop engineering. Pluripotent callus cells develop into fertile shoots through shoot regeneration. The molecular basis of the shoot regeneration process in crop callus remains largely elusive. This study pioneers the exploration of the spatial transcriptome of tomato callus during shoot regeneration. The findings reveal the presence of highly heterogeneous cell populations within the callus, including epidermis, vascular tissue, shoot primordia, inner callus, and outgrowth shoots. By characterizing the spatially resolved molecular features of shoot primordia and surrounding cells, specific factors essential for shoot primordia formation are identified. Notably, chlorenchyma cells, enriched in photosynthesis-related processes, play a crucial role in promoting shoot primordia formation and subsequent shoot regeneration. Light is shown to promote shoot regeneration by inducing chlorenchyma cell development and coordinating sugar signaling. These findings significantly advance our understanding of the cellular and molecular aspects of shoot regeneration in tomato callus and demonstrate the immense potential of spatial transcriptomics in plant biology.


Assuntos
Solanum lycopersicum , Solanum lycopersicum/genética , Transcriptoma , Células Epiteliais , Perfilação da Expressão Gênica , Regeneração/genética
2.
Proc Natl Acad Sci U S A ; 119(46): e2211786119, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36343232

RESUMO

The discovery of quantum interference (QI) is widely considered as an important advance in molecular electronics since it provides unique opportunities for achieving single-molecule devices with unprecedented performance. Although some pioneering studies suggested the presence of spin qubit coherence and QI in collective systems such as thin films, it remains unclear whether the QI can be transferred step-by-step from single molecules to different length scales, which hinders the application of QI in fabricating active molecular devices. Here, we found that QI can be transferred from a single molecule to their assemblies. We synthesized and investigated the charge transport through the molecular cages using 1,3-dipyridylbenzene (DPB) as a ligand block with a destructive quantum interference (DQI) effect and 2,5-dipyridylfuran (DPF) as a control building block with a constructive quantum interference (CQI) effect using both single-molecule break junction and large area junction techniques. Combined experiments and calculations revealed that both DQI and CQI had been transferred from the ligand blocks to the molecular cages and the monolayer thin film of the cages. Our work introduced QI effects from a ligand to the molecular cage comprising 732 atoms and even their monolayers, suggesting that the quantum interference could be scaled up within the phase-coherent distance.

3.
Small ; 20(8): e2305607, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37817357

RESUMO

The molecule-electrode coupling plays an essential role in photoresponsive devices with photochromic molecules, and the strong coupling between the molecule and the conventional electrodes leads to/ the quenching effect and limits the reversibility of molecular photoswitches. In this work, we developed a strategy of using transition metal dichalcogenides (TMDCs) electrodes to fabricate the thiol azobenzene (TAB) self-assembled monolayers (SAMs) junctions with the eutectic gallium-indium (EGaIn) technique. The current-voltage characteristics of the EGaIn/GaOx //TAB/TMDCs photoswitches showed an almost 100% reversible photoswitching behavior, which increased by ∼28% compared to EGaIn/GaOx //TAB/AuTS photoswitches. Density functional theory (DFT) calculations showed the coupling strength of the TAB-TMDCs electrode decreased by 42% compared to that of the TAB-AuTS electrode, giving rise to improved reversibility. our work demonstrated the feasibility of 2D TMDCs for fabricating SAMs-based photoswitches with unprecedentedly high reversibility.

4.
Cardiovasc Diabetol ; 23(1): 154, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702735

RESUMO

BACKGROUND: Insulin resistance (IR) plays an important role in the pathophysiology of cardiovascular disease. Recent studies have shown that diabetes mellitus and impaired lipid metabolism are associated with the severity and prognosis of idiopathic pulmonary arterial hypertension (IPAH). However, the relationship between IR and pulmonary hypertension is poorly understood. This study explored the association between four IR indices and IPAH using data from a multicenter cohort. METHODS: A total of 602 consecutive participants with IPAH were included in this study between January 2015 and December 2022. The metabolic score for IR (METS-IR), triglyceride to high-density lipoprotein cholesterol (TG/HDL-C) ratio, triglyceride and glucose (TyG) index, and triglyceride-glucose-body mass index (TyG-BMI) were used to quantify IR levels in patients with IPAH. The correlation between non-insulin-based IR indices and long-term adverse outcomes was determined using multivariate Cox regression models and restricted cubic splines. RESULTS: During a mean of 3.6 years' follow-up, 214 participants experienced all-cause death or worsening condition. Compared with in low to intermediate-low risk patients, the TG/HDL-C ratio (2.9 ± 1.7 vs. 3.3 ± 2.1, P = 0.003) and METS-IR (34.5 ± 6.7 vs. 36.4 ± 7.5, P < 0.001) were significantly increased in high to intermediate-high risk patients. IR indices correlated with well-validated variables that reflected the severity of IPAH, such as the cardiac index and stroke volume index. Multivariate Cox regression analyses indicated that the TyG-BMI index (hazard ratio [HR] 1.179, 95% confidence interval [CI] 1.020, 1.363 per 1.0-standard deviation [SD] increment, P = 0.026) and METS-IR (HR 1.169, 95% CI 1.016, 1.345 per 1.0-SD increment, P = 0.030) independently predicted adverse outcomes. Addition of the TG/HDL-C ratio and METS-IR significantly improved the reclassification and discrimination ability beyond the European Society of Cardiology (ESC) risk score. CONCLUSIONS: IR is associated with the severity and long-term prognosis of IPAH. TyG-BMI and METS-IR can independently predict clinical worsening events, while METS-IR also provide incremental predictive performance beyond the ESC risk stratification.


Assuntos
Biomarcadores , Glicemia , Resistência à Insulina , Índice de Gravidade de Doença , Triglicerídeos , Adulto , Feminino , Humanos , Masculino , Biomarcadores/sangue , Glicemia/metabolismo , China/epidemiologia , HDL-Colesterol/sangue , Progressão da Doença , Hipertensão Pulmonar Primária Familiar/diagnóstico , Hipertensão Pulmonar Primária Familiar/sangue , Hipertensão Pulmonar Primária Familiar/fisiopatologia , Hipertensão Pulmonar Primária Familiar/mortalidade , Prognóstico , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Triglicerídeos/sangue
5.
Chemistry ; : e202402095, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38943462

RESUMO

In the cross-plane single-molecule junctions, the correlation between molecular aromaticity and conductance remained puzzling. Cross-plane break junction (XPBJ) provides new insight into understanding the role of aromaticity and conjugation to molecules on charge transport through the planar molecules. In this work, we investigated the modulation of cross-plane charge transport in pyrene derivatives by hydrogenation and substituents based on the XPBJ method that differs from those used in-plane transport. We measured the electrical conductance of the hydrogenated derivatives of the pyrenes and found that hydrogenation reduces conductance, and the fully hydrogenated molecule has the lowest conductance. Conductance of pyrene derivatives increased after substitution by both electron-donating and electron-withdrawing groups. By calculating, the trend in decreased conductance of hydrogenated pyrene was found to be consistent with the change in aromaticity. Electron-withdrawing substituents reduce the aromaticity of the molecule and narrow the HOMO-LUMO gap, while electron-donating groups increase the aromaticity but also narrow the gap. Our work reveals the potential of fine-tuning the structure of the pyrene molecule to control the cross-plane charge transport through the single-molecule junctions.

6.
Langmuir ; 40(4): 1988-2004, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38227964

RESUMO

Single-molecule electronics can fabricate single-molecule devices via the construction of molecule-electrode interfaces and also provide a unique tool to investigate single-molecule scale physicochemical processes at these interfaces. To investigate single-molecule electronic devices with desired functionalities, an understanding of the interface evolution processes in single-molecule devices is essential. In this review, we focus on the evolution of molecule-electrode interface properties, including the background of interface evolution in single-molecule electronics, the construction of different types of single-molecule interfaces, and the regulation methods. Finally, we discuss the perspective of future characterization techniques and applications for single-molecule electronic interfaces.

7.
Phytopathology ; 114(1): 200-210, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37435950

RESUMO

Plant-pathogenic phytoplasmas secrete specific virulence proteins into a host plant to modulate plant function for their own benefit. Identification of phytoplasmal effectors is a key step toward clarifying the pathogenic mechanisms of phytoplasma. In this study, Zaofeng3, also known as secreted jujube witches' broom phytoplasma protein 3 (SJP3), was a homologous effector of SAP54 and induced a variety of abnormal phenotypes, such as phyllody, malformed floral organs, witches' broom, and dwarfism in Arabidopsis thaliana. Zaofeng3 can also induce small leaves, dwarfism, and witches' broom in Ziziphus jujuba. Further experiments showed that the three complete α-helix domains predicted in Zaofeng3 were essential for induction of disease symptoms in jujube. Yeast two-hybrid library screening showed that Zaofeng3 mainly interacts with proteins involved in flower morphogenesis and shoot proliferation. Bimolecular fluorescence complementation assays confirmed that Zaofeng3 interacted with these proteins in the whole cell. Overexpression of zaofeng3 in jujube shoot significantly altered the expression patterns of ZjMADS19, ZjMADS47, ZjMADS48, ZjMADS77, and ZjTCP7, suggesting that overexpressing zaofeng3 might induce floral organ malformation and witches' broom by altering the expression of the transcriptional factors involved in jujube morphogenesis.


Assuntos
Arabidopsis , Cytisus , Nanismo , Phytoplasma , Ziziphus , Phytoplasma/genética , Doenças das Plantas/genética , Plantas , Proliferação de Células
8.
Nano Lett ; 23(20): 9399-9405, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37877237

RESUMO

An accurate rule for predicting conductance is the cornerstone of developing molecular circuits and provides a promising solution for miniaturizing electric circuits. The successful prediction of series molecular circuits has proven the possibility of establishing a rule for molecular circuits under quantum mechanics. However, the quantitatively accurate prediction has not been validated by experiments for parallel molecular circuits. Here we used 1,3-dihydrobenzothiophene (DBT) to build the parallel molecular circuits. The theoretical simulation and single-molecule conductance measurements demonstrated that the conductance of the molecule containing one DBT is the unprecedented linear combination of the conductance of the two individual channels with respective contribution weights of 0.37 and 0.63. With these weights, the conductance of the molecule containing two DBTs is predicted as 1.81 nS, matching perfectly with the measured conductance (1.82 nS). This feature offers a potential rule for quantitatively predicting the conductance of parallel molecular circuits.

9.
J Environ Manage ; 364: 121435, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38889646

RESUMO

The abuse and uncontrolled discharge of antibiotics present a severe threat to environment and human health, necessitating the development of efficient and sustainable treatment technology. In this work, we employ a facile one-step electrodeposition method to prepare polyaniline/graphite oxide (PANI/GO) and samarium (Sm) co-modified Ti/PbO2 (Ti/PbO2-PANI/GO-Sm) electrode for the degradation of amoxicillin (AMX). Compared with traditional Ti/PbO2 electrode, Ti/PbO2-PANI/GO-Sm electrode exhibits more excellent oxygen evolution potential (2.63 V) and longer service life (56 h). In degradation experiment, under optimized conditions (50 mg L-1 AMX, 20 mA cm-2, pH 3, 0.050 M Na2SO4, 25 °C), Ti/PbO2-PANI/GO-Sm electrode achieves remarkable removal efficiencies of 88.76% for AMX and 79.92% for chemical oxygen demand at 90 min. In addition, trapping experiment confirms that ·OH plays a major role in the degradation process. Based on theoretical calculation and liquid chromatography-mass spectrometer results, the heterocyclic portion of AMX molecule is more susceptible to ·OH attacks. Thus, this novel electrode offers a sustainable and efficient solution to address environmental challenges posed by antibiotic-contaminated wastewater.


Assuntos
Amoxicilina , Eletrodos , Amoxicilina/química , Titânio/química , Poluentes Químicos da Água/química , Samário/química
10.
Molecules ; 29(11)2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38893316

RESUMO

For designing single-molecule devices that have both conjugation systems and structural flexibility, a hyperconjugated molecule with a σ-π bond interaction is considered an ideal candidate. In the investigation of conductance at the single-molecule level, since few hyperconjugation systems have been involved, the strategy of building hyperconjugation systems and the mechanism of electron transport within this system remain unexplored. Based on the skipped-conjugated structure, we present a rational approach to construct a hyperconjugation molecule using a hydroxyl group, which serves as a bridge to interact with the conjugated fragments. The measurement of single-molecule conductance reveals a two-fold conductance enhancement of the hyperconjugation system having the 'bridging' hydroxyl group compared to hydroxyl-free derivatives. Theoretical studies demonstrate that the hydroxyl group in the hyperconjugation system connects the LUMO of the two conjugated fragments and opens a through-space channel for electron transport to enhance the conductance.

11.
J Am Chem Soc ; 145(39): 21679-21686, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37747934

RESUMO

The charge transport through supramolecular junctions exhibits unique quantum interference (QI) effects, which provide an opportunity for the design of supramolecular transistors. Benefiting from the configuration dependence of QI, configuration control of the supramolecular assemblies to demonstrate the QI features is a key but challenging step. In this work, we fabricated the supramolecular transistors and investigated the charge transport through the conducting channel of the individual π-stacked thiophene/phenylene co-oligomers (TPCOs) using the electrochemically gated scanning tunneling microscope break junction technique. We controlled the configuration of the supramolecular channel and switched the QI features between the anti-resonance and resonance states of the supramolecular channels. We observed the supramolecular transistor with its on/off ratio above 103 (∼1300), a high gating efficiency of ∼165 mV/dec, a low off-state leakage current of ∼30 pA, and the channel length scaled down to <2.0 nm. Density functional theory calculations suggested that the QI features in π-stacked TPCOs vary depending on the supramolecular architecture and can be manipulated efficiently by fine-tuning the supramolecular configurations. This work reveals the potential of the supramolecular channels for molecular electronics and provides a fundamental understanding of intermolecular charge transport.

12.
Circ J ; 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38030266

RESUMO

BACKGROUND: The link between malnutrition and poor prognosis in cardiovascular disease has been established but the association between malnutrition and contrast-associated acute kidney injury (CA-AKI), a common complication of coronary procedures, remains poorly understood. In this study we investigated the predictive value of 3 nutritional indexes for CA-AKI in patients undergoing percutaneous coronary intervention (PCI).Methods and Results: The study included a total of 6,049 consecutive patients undergoing PCI between May 2012 and September 2020, among whom 352 (5.8%) developed CA-AKI. We used the Controlling Nutritional Status (CONUT) score, the Geriatric Nutritional Risk Index (GNRI), and the Prognostic Nutritional Index (PNI) to assess the association between malnutrition risk and CA-AKI after PCI. Multivariate logistic regression analysis revealed that malnutrition, as identified by GNRI and PNI, was significantly associated with a higher risk of CA-AKI (moderate-severe malnutrition in GNRI: odds ratio [OR]=1.92, [95% confidence interval (CI), 1.27-2.85]; malnutrition in PNI: OR=1.87, [95% CI, 1.39-2.50]), whereas the CONUT score did not demonstrate a significant difference (P>0.05). Furthermore, GNRI (∆AUC=0.115, P<0.001) and PNI (∆AUC=0.101, P<0.001) exhibited superior predictive ability than the CONUT score for CA-AKI and significantly improved reclassification and discrimination in the fully adjusted model. CONCLUSIONS: Malnutrition, especially identified by the GNRI and PNI, was associated with a higher risk of CA-AKI after PCI. GNRI and PNI performed better than the CONUT score in predicting CA-AKI.

13.
Anal Chem ; 94(35): 12042-12050, 2022 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-35971273

RESUMO

The tunneling current through the single-molecule junctions principally offers the ultimate solution for chemical and biochemical sensing via the interactions between probes and target analytes at the single-molecule level. However, it remains unexplored to achieve the sensitive and selective detection of targeted analytes using single-molecule junction techniques due to the challenge in quantitative evaluation of sensing sensitivity and selectivity. Herein, we demonstrate a single-molecule tunneling sensor for the highly sensitive and selective detection of nitrobenzene explosives using scanning tunneling microscope break junction (STM-BJ). Taking advantage of π-π stacking interactions between the molecular probes and nitrobenzene explosives, we use a spectral clustering algorithm to assign the signal of probes and π-stacked probes for sensitively detecting the targeted analytes and the distinguishable conductance change of probes when interacting with different nitroaromatic explosive compounds for selective detection. We find that pronounced conductance changes up to 0.8 orders of magnitude when the probes interact with TNT. Also, we obtain a sensitivity of up to ∼10 pM for TNT and high sensitivity for eight TNT analogues. Combined with theoretical calculations, we discover that the harness of the destructive quantum interference of the probe M1OH after interacting with TNT leads to high selectivity in sensing with TNT. Our work demonstrates the great potential of the single-molecule tunneling current for environmental sensing molecules with high selectivity and sensitivity.


Assuntos
Substâncias Explosivas , Nanotecnologia , Nitrobenzenos
14.
Small ; 18(20): e2200361, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35481610

RESUMO

Investigating the correlations of electron transport between multiple channels shows vital promises for the design of molecule-scale circuits with logic operations. To control the electron transport through multiple channels, the modulation of electronegativity shows an effective frontier orbit control method with high universality to explore the interactions between transport channels. Here, two series of compounds with a single nitrogenous conductive channel (Sg) and dual-channels (Db) are designed to explore the influence of electronegativity on electron tunneling transport. Single-molecule conductance measured via the scanning tunneling microscope break junction technique (STM-BJ) reveals that the conductance of Db series is significantly suppressed as the electronegativity of nitrogen becomes negative, while the suppression on Sg is less obvious. Theoretical calculations confirm that the effect of electronegativity extends to a dispersive range of molecular frameworks owing to the delocalized orbital distribution from the dual-channel structure, resulting in a more significant conductance suppression effect than that on the single-channel. This study provides the experimental and theoretical potentials of electronegativity gating for molecular circuits.


Assuntos
Nanotecnologia , Nitrogênio , Condutividade Elétrica , Transporte de Elétrons
15.
Small ; 18(10): e2107220, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34927352

RESUMO

The electronic noise characterization of single-molecule devices provides insights into the mechanisms of charge transport. In this work, it is reported that flicker noise can serve as an indicator of the time-dependent evolution of charge transport mechanisms in the single-molecule break junction process. By introducing time-frequency analysis, the authors find that flicker noise components of the molecule junction show time evolution behavior in the dynamic break junction process. A further investigation of the power-law dependence of flicker with conductance during the dynamic break junction process reveals that the mechanism of charge transport transits from the through-space transport to the through-bond transport, and is dominated by through-space transport again when the junction is about to rupture. The authors' results provide a flicker noise-based way to characterize the time-dependent evolution of charge transport mechanisms in single-molecule break junctions.


Assuntos
Eletrônica , Nanotecnologia
16.
Immunopharmacol Immunotoxicol ; 44(6): 886-893, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35815670

RESUMO

BACKGROUND: The inhibitory effect of Tetrandrine (Tet) on rheumatoid arthritis (RA) is well established. However, its exact molecular mechanism remains unknown. METHODS: RT-qPCR coupled with western blotting was employed to analyze the expression of NEAT1, miR-17-5p, and STAT3 in RA tissues and/or RA-fibroblast-like synoviocytes (RA-FLS) treated with 3 µmol/L of Tet for 48 h. Cell Counting Kit-8 assay and flow cytometry were performed to assess RA-FLS proliferation and apoptosis. Luciferase reporter assays were used to validate the interactions between miR-17-5p and STAT3 or NEAT1. RESULTS: The expression of NEAT1 decreased in a time-dependent manner upon Tet treatment. Tet significantly inhibited RA-FLS proliferation and triggered apoptosis by downregulating NEAT1 expression. Additionally, NEAT1 directly targeted miR-17-5p to upregulate STAT3 expression. Tet-induced low NEAT1 expression impaired RA-FLS growth by targeting miR-17-5p and inhibiting STAT3. CONCLUSION: Tet exerts its inhibitory role in RA progression by regulating the NEAT1/miR-17-5p/STAT3 pathway.


Assuntos
Artrite Reumatoide , MicroRNAs , RNA Longo não Codificante , Humanos , RNA Longo não Codificante/genética , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/genética , MicroRNAs/genética , Fator de Transcrição STAT3/genética
17.
Angew Chem Int Ed Engl ; 61(40): e202210097, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-35981229

RESUMO

The Fano resonance in single-molecule junctions could be created by interaction with discrete and continuous molecular orbitals and enables effective electron transport modulation between constructive and destructive interference within a small energy range. However, direct observation of Fano resonance remains unexplored because of the disappearance of discrete orbitals by molecule-electrode coupling. We demonstrated the room-temperature observation of Fano resonance from electrochemical gated single-molecule conductance and current-voltage measurements of a para-carbazole anion junction. Theoretical calculations reveal that the negative charge on the nitrogen atom induces a localized HOMO on the molecular center, creating Fano resonance by interfering with the delocalized LUMO on the molecular backbone. Our findings demonstrate that the Fano resonance in electron transport through single-molecule junctions opens pathways for designs of interference-based electronic devices.

18.
Small ; 16(39): e2002808, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32851802

RESUMO

As stated in the classic Kirchhoff's circuit laws, the total conductance of two parallel channels in an electronic circuit is the sum of the individual conductance. However, in molecular circuits, the quantum interference (QI) between the individual channels may lead to apparent invalidity of Kirchhoff's laws. Such an effect can be very significant in single-molecule circuits consisting of partially overlapped multiple transport channels. Herein, an investigation on how the molecular circuit conductance correlates to the individual channels is conducted in the presence of QI. It is found that the conductance of multi-channel circuit consisting of both constructive and destructive QI is significantly smaller than the addition of individual ones due to the interference between channels. In contrast, the circuit consisting of destructive QI channels exhibits an additive transport. These investigations provide a new cognition of transport mechanism and manipulation of transport in multi-channel molecular circuits.

19.
J Am Chem Soc ; 140(21): 6531-6535, 2018 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-29690767

RESUMO

Distinguishing structural isomers at the single-molecule level remains a challenge. We report the single-molecule recognition of two diketopyrrolopyrrole containing isomers (SDPP and SPPO) employing the mechanically controllable break junction technique. The single-molecule conductances of the two isomers are indistinguishable under normal conditions. However, reversible protonation and deprotonation of the SPPO in molecular junction result in more than 1 order of magnitude conductance change, which dramatically enhances the conductance difference between the two isomers. Theoretical study reveals that the dramatic conductance switching is due to reversible quantum interference effect. It is suggested that combination of stimuli-response and quantum interference can be an efficient strategy to enhance isomer recognition and conductance switching in single-molecule junctions.

20.
Chemistry ; 23(57): 14375-14383, 2017 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-28758338

RESUMO

The buckybowl trichalcogenasumanenes show cleavage of flanking benzene ring upon oxidation, which leads their dissection by fusing various amidine moieties onto peripheral region. By gradually increasing the ring size of amidine from five- to six- and seven-membered, the molecule engineering results in the [7-5-6]-, [7-6-6]-, and [7-7-6]-fused polycycles. Three systems are distinct in the molecular geometries, packing motifs, and optoelectronic properties. The [7-5-6]-fused case adopts the flat backbone, displays strong emission with the fluorescence quantum yield up to 52.3 %, and undergoes a two-photon absorption process. The [7-6-6]-fused one is of a curvature with molecular geometry inversion, forms a tight stack of curved π-system, shows broad absorption extended to 700 nm, and exhibits the p-type semiconducting behavior with hole mobility of 4.4×10-3  cm2 V-1 s-1 . The [7-7-6]-fused one possesses the highly twisted skeleton to show stable chirality, and exhibits red emission in both solution and solid state. The surgery on trichalcogenasumanene is a promising approach to create polycycles with diverse functionalities.

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