Functionalized polycyclic aromatic hydrocarbons (PAHs) are essential building blocks for the bottom-up fabrication of structurally uniform nanocarbons. Herein we report a simple and efficient synthetic method toward K-region hydroxy-functionalized PAHs via TEMPO-mediated twofold intramolecular C-H/C-H arylations of 1-biphenyl-2-yl-2-aryl-ethanone derivatives. This method achieves high yields and selectivity, synthesizing a variety of PAH frameworks, including pyrenes, chrysenes, benzo[]phenanthrenes, and benzo[]tetraphenes.
View Article and Find Full Text PDFThe properties of π-functional materials are predominantly influenced by both their molecular structures and interactions between π-systems. Recent advancements have focused on modifying the geometry or topology of π-molecules from planar to nonplanar conformations to tailor molecular properties. However, the interactions among nonplanar π-molecules remain largely unexplored, likely due to the significant reduction in contact surfaces arising from their curved structures.
View Article and Find Full Text PDFPhysiol Mol Biol Plants
September 2024
Severe burns related to fires and explosions of lithium-ion batteries of electric motorcycles have not been reported to date. We retrospectively studied 419 patients admitted to our burn intensive care unit from January 2016 to December 2021. Of these 419 patients, 26 (22 male, 4 female; median age, 42 years) had burns related to lithium-ion battery fires and explosions, and all of their injury characteristics were similar to those of traditional flame burns.
View Article and Find Full Text PDFHighly organized π-aggregate architectures can strongly affect electronic couplings, leading to important photophysical behaviors. With the escalating interest in two-dimensional (2D) materials attributed to their exceptional electronic and optical characteristics, there is growing anticipation that 2D radial-π-stacks built upon radial π-conjugation nanorings, incorporating intra- and inter-ring electronic couplings within the confines of a 2D plane, will exhibit superior topological attributes and distinct properties. Despite their immense potential, the design and synthesis of 2D π-stacks have proven to be a formidable challenge due to the insufficient π-π interactions necessary for stable stacking.
View Article and Find Full Text PDFThe properties of functional materials based on organic π-conjugated systems are governed extensively by intermolecular interactions between π-molecules. To establish clear relationships between supramolecular structures and functional properties, it is essential to attain structurally well-defined π-stacks, particularly in solution, as this enables the collection of valuable spectroscopic data. However, precise control and fine-tuning of π-stacks pose significant challenges due to the weak and bidirectional nature of π-π stacking interactions.
View Article and Find Full Text PDFIn this study, we investigate the effects of ligands on C-H activation during rhodium(III)-catalyzed C-H bond olefination reactions using well-defined [CpRh] catalytic systems with three representative Cp (Cp (η-CH), Cp (η-CMeCF), and Cp* (η-CMe)) ligands. Our results demonstrate that C-H activation as the rate-limiting step is significantly influenced by the steric properties of the Cp ligands. Moreover, we observe a dramatic acceleration of the simple [CpRh]-catalyzed C-H olefination reaction with acid coproducts such as HOAc, implying an autocatalytic C-H activation process.
View Article and Find Full Text PDFType III electrical burns on the wrist are characterized by circumferential wounds, three dimensional with sandwich-like necrosis, and progressive blood circulation disturbances. Limb salvage is challenging, and success in meeting this challenge depends on vascular reconstruction and wound coverage. This article is intended for the following purposes: to investigate the principles of wound debridement, the management of involved blood vessels, and the clinical effects of the extended paraumbilical perforator flap pedicled with the inferior epigastric artery for coverage of type III circumferential electrical burns of the wrist.
View Article and Find Full Text PDFHeavy metal pollution in testing ranges is one of the most widely concerning environmental problems. The ammunition static detonation test area, the bomb falling area, and the living area of a testing range in Jilin were selected as the study objects. The contents of heavy metals (As, Cd, Cr, Cu, Ni, Pb, and Zn) in 112 topsoil samples and two soil profiles were analyzed, and their distribution characteristics and sources were analyzed in detail.
View Article and Find Full Text PDFNatural light-harvesting (LH) systems can divide identical dyes into unequal aggregate states, thereby achieving intelligent "allocation of labor". From a synthetic point of view, the construction of such kinds of unequal and integrated systems without the help of proteinaceous scaffolding is challenging. Here, we show that four octatetrayne-bridged ortho-perylene diimide (PDI) dyads (POPs) self-assemble into a quadruple assembly (POP) both in solution and in the solid state.
View Article and Find Full Text PDFAim: To explore the prevalence and related factors influencing diabetes stigma among Chinese young and middle-aged patients with type 2 diabetes.
Design: A cross-sectional, quantitative study was conducted through questionnaires.
Methods: A total of 453 young and middle-aged patients with type 2 diabetes were recruited.
Background: Microvascular tissue reconstruction is a well-established, commonly used technique for a wide variety of the tissue defects. However, flap failure is associated with an additional hospital stay, medical cost burden, and mental stress. Therefore, understanding of the risk factors associated with this event is of utmost importance.
View Article and Find Full Text PDFA number of - and -shaped perylene diimide (PDI) heterohelicenes with high dipole moments were synthesized from simple perylene tetrabutylester (PTE). Taking advantage of the weak coordination ability of the sterically crowded peri ester groups in PTE, efficient Rh(III)-catalyzed 2,8- and 2,11-bisiodinations of the perylene core were realized. The 2,8- and 2,11-diiodinated PTEs and PDIs represent key synthons for further -π-extensions.
View Article and Find Full Text PDFAs the global climate warms, more creatures are threatened by high temperatures, especially cold-water fish such as rainbow trout. Evidence has demonstrated that long noncoding RNAs (lncRNAs) play a pivotal role in regulating heat stress in animals, but we have little understanding of this regulatory mechanism. The present study aimed to identify potential key lncRNAs involved in regulating acute heat stress in rainbow trout.
View Article and Find Full Text PDFRetinitis pigmentosa is a retinal disease characterized by photoreceptor degeneration. There is currently no effective treatment for retinitis pigmentosa. Although a mixture of lutein and other antioxidant agents has shown promising effects in protecting the retina from degeneration, the role of lutein alone remains unclear.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
November 2021
The synthesis, structures, and properties of [4]cyclonaphthodithiophene diimides ([4]C-NDTIs) are described. NDTIs as important n-type building blocks were catenated in the α-positions of thiophene rings via an unusual electrochemical-oxidation-promoted macrocyclization route. The thiophene-thiophene junction in [4]C-NDTIs results in an ideal pillar shape.
View Article and Find Full Text PDFBackground & Aims: Previous randomized controlled trials (RCTs) have compared the effects of pure preparations of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in reducing metabolic syndrome (MetS) risk factors, but the results were inconsistent. The present study aimed to clarify whether EPA and DHA have differential effects on MetS features in humans.
Methods: A systematic literature search was conducted in CNKI, PubMed, Embase and Scopus updated to February 2021.
Background: The main mechanism of keloid formation is that keloid fibroblasts (KFs) apoptosis is inhibited, leading to excessive proliferation. Transforming growth factor-β1 (TGF-β1) is a key signal molecule in the process of regulating cell fibrosis. This paper discusses the effect of adipose-derived stem cell exosomes (ADSCs-EXO) on the proliferation and apoptosis of KFS and its possible mechanism, in order to provide reference for the clinical intervention of hypertrophic scar.
View Article and Find Full Text PDFLuteolin is neuroprotective for retinal ganglion cells and retinal pigment epithelial cells after oxidative injury, whereby it can inhibit microglial neurotoxicity. Therefore, luteolin holds the potential to be useful for treatment of retinal diseases. The purpose of this study was to investigate whether luteolin exhibits neuroprotective effects on rod cells in rd10 mice, a slow photoreceptor-degenerative model of retinitis pigmentosa.
View Article and Find Full Text PDFDespite great challenges, the development of new molecular structures with multiple and even conflicting characteristics are eagerly pursued for exploring advanced applications. To develop high-performance chiral organic semiconducting molecules, a distorted π-system is required for strong coupling with circularly polarized light (CPL), whereas planar π-stacking systems are necessary for high charge-carrier mobility. To address this dilemma, in this work, we introduce a skeleton merging approach through distortion of a perylene diimide (PDI) core with four fused heteroaromatics to form an ortho-π-extended PDI double-[7]heterohelicene.
View Article and Find Full Text PDFLung cancer is the leading cause of cancer-related deaths mainly attributable to metastasis, especially extrathoracic metastasis. This large-cohort research is aimed to explore metastatic profiles in different histological types of lung cancer, as well as to assess clinicopathological and survival significance of diverse metastatic lesions. Lung cancer cases were extracted and enrolled from the Surveillance, Epidemiology, and End Results (SEER) database.
View Article and Find Full Text PDFNi-catalyzed intermolecular allylic dearomatization reaction of β-naphthols with allylic alcohols was achieved. By utilizing Ni(cod) as a catalyst precursor, DPEphos as a ligand and 4 Å molecular sieves as additives, the dearomatization reaction of β-naphthols with aryl allylic alcohols proceeded smoothly under mild conditions, affording the desired β-naphthalenone products bearing a quaternary carbon center in moderate to good yields with excellent linear selectivity.
View Article and Find Full Text PDFConventionally, -direction modulation of two-dimensional covalent organic frameworks (2D-COFs) is difficult to achieve because they rely on spontaneous π-π interactions to form 3D architectures. Herein, we report a facile construction of a novel intercalated covalent organic framework (Intercalated-COF) by synchronizing operations of supramolecular donor-acceptor (D-A) interactions (A unit: 2,5,8,11-tetra(-formylphenyl)-perylene diimide (PDI) ; D unit: perylene , as intercalator) in the vertical directions, with polymerizations (by only reacting with -phenylenediamine ) in the lateral directions. In this Intercalated-COF, the PDI-based covalent 2D layers are uniformly separated by perylene guest layers.
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