Search

The ring-opening reaction of aromatic molecules is a significant and critical process for the construction of carbon-based and related functional materials with desired structures and properties. However, direct observation and control of such a process at a molecular level remains a challenge. Here, we employed the octahedral voids in endohedral metallofullerene (EMF) crystals as nanoreactors to accommodate aromatic m-xylene molecules and regulate the ring-opening reaction of guest m-xylene by applying a high pressure. We found that the ring-opening reaction of m-xylenes strongly depends on the degree of charge transfer between m-xylene and EMF, which can be tuned by varying the electronegativity of the carbon cages with different endohedral metals. A positive relationship between the electronegativity of fullerenes and the reactivity of m-xylene was revealed. This work demonstrates the potential of tuning the ring-opening reaction of aromatic molecules by charge transfer and manipulates the reaction at a molecule level, providing new insights into the synthesis of carbon materials and fullerene derivatives. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study was to assess the diagnostic performance of narrow‐band imaging (NBI) in monitoring patients with head and neck carcinomas posttreatment and to compare it with that of white light endoscopy (WLE). Data Sources: PubMed, Embase, Web of Science (WOS), Cochrane Library, China Biology Medicine disc (CBM disc), China National Knowledge Internet (CNKI), Wanfang Data, China Science and Technology Journal Database (CSTJ), Chinese Clinical Trial Register. Review Methods: Using the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA), literature published before July 2024 was searched. Patients who underwent surgery, radiotherapy (RT), or chemo‐RT for head and neck carcinomas with posttreatment follow‐up using NBI were analyzed. The main outcomes were sensitivity, specificity, and diagnostic odds ratio (DOR) for NBI and WLE in posttreatment follow‐up. Results: The sensitivity, specificity, and DOR for NBI and WLE in posttreatment follow‐up for head and neck carcinomas were 95% (95% confidence interval [CI]: 88%–98%), 96% (95% CI: 92%–98%), 433 (95% CI: 120–1560) and 72% (95% CI: 49%–87%), 72% (95% CI: 4%–99%), 7 (95% CI: 0–191). Additionally, the area under the curve (AUC) values for NBI and WLE were 0.99 (95% CI: 0.97–0.99) and 0.75 (95% CI: 0.71–0.79), respectively. The number of lesions and patients, treatment modality, follow‐up time, disease, and endoscopic system might be sources of heterogeneity. Conclusion: Compared to WLE, NBI demonstrated superior diagnostic performance in follow‐up patients with head and neck carcinoma posttreatment. NBI offers technical support and a clinical foundation for early detection of head and neck carcinoma recurrence. Level of Evidence: NA Laryngoscope, 135:34–44, 2025 [ABSTRACT FROM AUTHOR]

A series of reported Pt(II) carbene complexes possibly have the ability to serve as the new generation of blue emitters in luminescent devices because of their narrow emission spectra, high photoluminescence quantum yields (PLQYs), and rigid molecular skeleton. However, the combination of all carbene ligands with different multidentate structures will affect the overall planarity and horizontal dipole ratio to varying degrees, but the specific extent of this effect has not previously been analyzed in detail. In this work, density functional computation is used to study a class of platinum tetracarbene bidentate complexes with similar absorption and emission band characteristics, which is the main reason for the remarkable difference in quantum efficiency due to subtle differences in electronic states caused by different ligands. From the calculation results, the major reason, which results in significantly decrease in quantum efficiency for [Pt(cyim)2]2+, is that [Pt(cyim)2]2+ can reach the non-radiative deactivation metal-centered d-d excited state through an easier pathway compared with [Pt(meim)2]2+. The result, based on changes in the dihedral angle between ligands, can achieve the goal of improving and designing materials by adjusting the degree of the dihedral angle. (meim: bis(1,1′-dimethyl-3,3′-methylene-diimidazoline-2,2′-diylidene); cyim: bis(1,1′-dicyclohexyl-3,3′-methylene-diimidazoline-2,2′-diylidene).

In aluminum alloy double pulse metal inert-gas (DPMIG) welding, the outputting arc current waveform is distorted under the influence of various factors such as harmonics and impact loads. The arc distortion of aluminum alloy DPMIG welding affects the arc stability and welding quality. Based on the collected welding current signal, a feature extraction method is proposed for quality detection of the aluminum alloy DPMIG welding. The wavelet method is adopted to eliminate the noise of the welding current signal. The local mean decomposition (LMD) is performed to the welding current signal to obtain a series of Product Function (PF) components with real physical meaning. The Hilbert transformation is subsequently performed to the PF components to obtain the time frequency distribution of welding arc signal energy. The approximate entropy (ApEn) of the time frequency distribution of the welding current signal is calculated to evaluate the arc stability and the welding formation quality. Application of the proposed feature extraction method indicates that the combination of the wavelet and LMD can effectively extract the distortion components of the welding current signal. The time frequency distribution of the PF components of the welding current can clearly reflect the concentration and dispersion of the arc energy. The approximate entropy of the time frequency distribution of the welding current can be quantitively reflect the arc stability and the welding formation quality in the aluminum alloy double pulse MIG welding.

A phytochemical investigation on the 80% EtOH extract of the fruiting bodies of Ganoderma tsugae resulted into the isolation of two previously undescribed lanostane triterpenoids, 7,11-dioxo-3β-acetyloxy-26,27-dihydroxy-lanosta-8,24-diene (1) and 7,20-dioxo-3β-acetyloxy-11β,15α-dihydroxy-22,23,24,25,26,27-hexanorlanosta-8-ene (2), togeher with one known lanostane triterpenoid ganodermanontriol (3). Structural elucidation of all the compounds were performed by spectral methods such as 1D and 2D (1H-1H COSY, HMQC, and HMBC) NMR spectroscopy. All the triterpenoids were in vitro evaluated for their antibacterial activities against six pathogenic microorganisms. Compound 3 exhibited some activities against three Gram positive bacteria with MIC values less than 30 μg/ml. [ABSTRACT FROM AUTHOR]

Konjac glucomannan consists of D-mannose and D-glucose units and is a hydrocolloid obtained from the corm of Amorphophallus species. Due to its bioactive properties, biodegradability, and hydrophilic ability, glucomannan is widely used in the fields of food, medicine, and industry. Amorphophallus species have been cultivated as cash crops in many Asian countries. Amorphophallus kachinensis Engler & Gehrmann 1911 is naturally distributed in southwestern China, Laos, and northern Thailand. To help the genetic assessment and conservation of this species, the first chloroplast genome of A. kachinensis was sequenced on the Illumina sequencing platform. We assembled the chloroplast genome using the software GetOrganelle and annotated the genome by Geseq and Cpgavas 2. The assembled chloroplast genome was 173,330 bp long, and the average GC content was 35% (GenBank accession number: PP072244). The chloroplast genome of A. kachinensis contained one large single copy, one small single copy, and two inverted repeats, with lengths of 92,030 bp, 15,118 bp, 33,091 bp, and 33,091 bp, respectively. We successfully annotated 132 genes across the genome, which was consistent with other Amorphophallus species. The phylogenetic tree indicates a sub-divergence in the Amorphophallus genus with two main genetic groups detected among eight species. The two genetic groups should be treated as distinct evolutionarily significant units when making conservation strategies. Our study enriched the chloroplast genome resources of the Amorphophallus genus and could help future phylogeographic studies, protection, and utilization of wild resources. [ABSTRACT FROM AUTHOR]

Angiolipoma in the region of the hypopharynx-esophageal introitus is a rare occurrence. Surgical treatment was performed in the few cases reported in the literature. Endoscopic submucosal dissection (ESD) is a minimally invasive treatment for hypopharyngeal and esophageal lesions. Our objective was to evaluate the feasibility, safety, and efficacy of ESD for treatment of angiolipoma at the hypopharynx-esophageal introitus. The patients with submucosal tumors at the hypopharynx-esophageal introitus were diagnosed as angiolipoma by preoperative evaluation with endoscopy, endoscopic ultrasonography, and computed tomography (CT). The patients who were diagnosed with angiolipoma agreed to undergo endoscopic submucosal dissection. Under general anesthesia and endotracheal intubation, ESD was used to remove the lesions. Preoperative, intraoperative, and postoperative data were collected and analyzed to evaluate the feasibility, safety, and effectiveness of endoscopic submucosal dissection. From January 2013 to December 2018, 6 cases of angiolipoma were treated with ESD with a success rate of 100%. The average operation time was 107.0±69.4 minutes. Intraoperative blood loss is the main risk. Endoscopic thermocoagulation successfully stopped bleeding in all cases. Pharyngeal pain and painful swallowing were the main clinical signs. There was no stricture at the hypopharynx-esophageal introitus after the operation. ESD treatment of angiolipoma at hypopharynx-esophageal introitus is feasible, safe, and effective.