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The design and synthesis of three-dimensional (3D) covalent organic frameworks (COFs) with exceptional stability and high proton conductivity are critical for advancing high-temperature fuel cells but remain significantly challenging. In this study, thiadiazole groups were successfully incorporated into a novel 3D COF featuring a five-fold interpenetrated diamond network through a bottom-up self-assembly strategy. The proton conduction of the thiadiazole-based 3D COF (NUST-28) under anhydrous conditions reached up to 8.40 × 10−2 S cm−1 at 120 °C after phosphoric acid doping. Furthermore, the NUST-28 conductor demonstrated good stability at constant temperature and in cyclic experiments. This work paves the way for the design and construction of 3D COFs as platforms for fast ion transportation using reticular chemistry. [ABSTRACT FROM AUTHOR]

Li-ion batteries become a hot spot in academic research in recent years. However, due to the incidents caused by the batteries, effective management measures are necessary for experimental safety of Li-ion batteries in universities. On the basis of analysis of the safety issue mechanism as well as management situation of Li-ion batteries experiment, the safety management measures are explored and studied. Based on the characteristics of Li-ion batteries experiment and lab safety management characteristics in universities, the new "threecompleteness" battery safety management system are proposed, including complete hierarchy, elements and process. The management measures are proposed from different perspectives of personnel, hazardous factors and experiment process. The management measures can provide new reference for the safety management of the batteries experiment of the universities, as well as safeguard for safe operation of the laboratories in universities. [ABSTRACT FROM AUTHOR]

Although covalent organic frameworks (COFs) with a graphene‐like structure present unique chemical and physical properties, they are essentially insoluble and infusible crystalline powders with poor processability, hindering their further practical applications. How to improve the processability of COF materials is a major challenge in this field. In this contribution, we proposed a general side‐chain engineering strategy to construct a gel‐state COF with high processability. This method takes advantages of large and soft branched alkyl side chains as internal plasticizers to achieve the gelation of the COF. We systematically studied the influence of the length of the side chain on the COF gel formation. Benefitting from their machinability and flexibility, this novel COF gel can be easily processed into gel‐type electrolytes with specific shape and thickness, which were further applied to assemble lithium‐ion batteries that exhibited high cycling stability. [ABSTRACT FROM AUTHOR]

Proton-conducting materials are key components for constructing high-energy-density electronic devices. In this work, by accumulating NH4Br into the nanospace of the classical metal organic framework MIL-101-Cr, a proton conductivity as high as 1.53 × 10−1 S cm−1 was achieved at 363 K and 100% RH. The proton conduction of NH4Br@MIL-101-Cr was also high even at lower relative humidity; for instance, it was ∼10−2 S cm−1 at 75% RH. The activation energy was calculated to be 0.11 eV for NH4Br@MIL-101-Cr, indicative of tight H-bond networks and a low barrier to proton transfer, and confirming the occurrence of pure proton conduction as well. [ABSTRACT FROM AUTHOR]

Objective: To investigate the diagnostic value of fluorine-18-9-fluoropropyl-(+)-dihydrotetrabenazine ( 18 F-AV-133) positron emission tomography/computed tomography (PET/CT) for Parkinson's disease (PD) and the metabolic parameter changes in the PD macaque model., Subjects and Methods: Sixty three macaques were divided into an experimental group (n=55) and a normal group (n=8) for 18 F-AV-133 PET/CT imaging. In the experimental group, the macaques were injected with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) solution into one side of the neck artery 2-3 months before imaging to induce unilateral striatal damage for self-control, while the normal group received no special treatment. After imaging, two nuclear medicine doctors conducted image analysis to determine the damaged side using visual inspection and compared the data with the actual damaged side to evaluate the model construction. The standardized uptake value (SUV) semi-quantitative analysis method was used to process the images, obtaining metabolic information of the damaged and preserved sides of the striatum, thalamus, occipital lobe, frontal lobe, parietal lobe, temporal lobe, and cerebellum in different sides of the normal group. Data analysis was performed using SPSS 25 to compare metabolic differences between different sides and evaluate the impact of modeling on the metabolism of other regions of the brain, with a significance level set at P<0.05., Results: Fluorine-18-AV-133 PET/CT imaging showed that the normal group of macaques exhibited relatively symmetrical radiotracer uptake in the bilateral striatal regions; the experimental group of PD macaque models showed completely asymmetrical radiotracer uptake in the left and right striatal regions, with model construction success rate of 100%. Semi-quantitative analysis using SUV revealed that the metabolic parameters SUVmax, SUVmean, metabolic tumor volume (MTV), and total lesion glycolysis (TLG) in the damaged striatal region of the experimental group of PD macaques were lower than those in the preserved side, with statistically significant differences (t/z=8.277, 12.032, 8.827, 8.744, P<0.001). The SUVmean in the damaged thalamus of the PD macaques was lower than in the preserved side (1.327±0.354 vs. 1.490±0.374), with a statistically significant difference (t=2.352, P=0.02).The metabolic parameters SUVmax, SUVmean, MTV, and TLG in the striatum of the normal group were higher than those in the preserved striatum of the experimental group, with P<0.05., Conclusion: Fluorine-18-AV-133 PET/CT can accurately assess the construction of PD macaque models and visualize the differences in metabolic parameters between different sides, making it useful for detecting monoaminergic terminal reduction in PD patients and providing a theoretical basis for the diagnosis and follow-up treatment of PD.

Objective: To explore the potential of intratumoral metabolism and its heterogeneous parameters, as measured by preoperative fluorine-18-fluorodeoxyglucose ( 18 F-FDG) positron emission tomography/computed tomography (PET/CT) imaging, to predict mediastinal occult lymph node metastasis in cN0 lung invasive adenocarcinoma., Subjects and Methods: Seventy five patients were consecutively enrolled from January 2018 to December 2022. All patients underwent 18 F-FDG PET/CT scans within two weeks before surgery, and had mediastinal lymph node metastasis confirmed by pathologic diagnosis after surgery. Metabolic parameters including the maximum standardized uptake value (SUVmax), mean SUV (SUVmean), maximum average SUV (SUVpeak), tumor metabolic volume (MTV), and metabolic heterogeneity (HF) were measured. The relationship between primary focal metabolism, its heterogeneity parameters, and occult mediastinal lymph node metastasis was analyzed using an independent-sample t-test, analysis of covariance, and Mann-Whitney U test. A multivariate logistic regression model was used to analyze independent risk factors for mediastinal lymph node metastasis, while the receiver operating characteristic (ROC) curve assessed the predictive value of metabolic heterogeneity parameters for mediastinal occult lymph node metastasis., Results: A total of 20 out of 75 patients (26.7%) were pathologically confirmed to have mediastinal lymph node metastasis. Analysis of covariance showed that the SUVmax, SUVmean, SUVpeak and MTV were significantly higher in patients with metastasis than in those without (all P<0.05). The metabolic heterogeneity parameters HF2 and HF3 were significantly higher in patients with mediastinal lymph node metastasis than in those without (P=0.013, 0.001), but not HF1. Multivariate Logistic regression analysis identified that tumor size, SUVmax, SUVpeak, lymph node SUVmax, and HF2 of the primary tumor as independent risk factors for mediastinal lymph node metastasis. Metabolic heterogeneity 3 demonstrated high predictive value for mediastinal occult lymph node metastasis (AUC=0.720, P=0.004)., Conclusion: Metabolism and heterogeneity, as measured by preoperative 18 F-FDG PET/CT in lung invasive adenocarcinoma, potentially have clinical value for predicting mediastinal occult lymph node metastasis.