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Rationale: Natural monomer flavors can modify the taste of cigarettes. However, no report was published to establish the quality control method for their chemical compositions. Methods: In this study, licorice, a traditional natural monomer flavor used in tobacco aroma processing, was selected, and the fingerprint was developed by high‐performance liquid chromatography (HPLC). Next, the chemical markers of samples from different places of origin were discovered by multivariate statistical analysis. Then, its chemical constituents were identified by combination of HPLC‐Fourier transform ion cyclotron resonance mass spectrometry (FT‐ICR‐MS), direct infusion FT‐ICR‐MS (DI‐FT‐ICR‐MS), and the technology of isotopic fine structures (IFSs). Moreover, its characteristic constituents were quantitatively analyzed using HPLC. Results: The 14 common peaks were assigned in the fingerprint, and 8 of them were considered as qualitative markers by multivariate statistical analysis. A total of 42 chemical constituents were detected using HPLC‐FT‐ICR‐MS, and 13 of them were unambiguously identified by references. Meanwhile, the elemental compositions of other eight unknown chemical components were decisively determined using IFSs. Subsequently, the contents of five characteristic constituents in 11 batches of samples were determined. Conclusions: The integration strategy established here can discover and quantify the chemical markers for improving the quality control standard of natural monomer flavor of licorice. It is expected that the strategy will be valuable for further quality control of other natural monomer flavors in Chinese tobacco industry. [ABSTRACT FROM AUTHOR]

Objective: The present study was aimed to comprehensively characterize the epidemiological, clinicopathological characteristics, treatments, and prognosis of intraoral spindle cell carcinoma (SpCC). Materials and Methods: Patients diagnosed with intraoral SpCC at our institution in the past 15 years (2005–2019) were screened from inpatient disease registry. All relevant data concerning patients with intraoral SpCC were retrieved. Previous reports about intraoral SpCC with adequate clinicopathological data in both English literature and Chinese literature were collected. Eligible cases were further reviewed and pooled for statistical analyses. Results: Six patients (5 females and 1 male; average age: 59 years) with intraoral SpCC were histopathologically diagnosed and surgically treated at our institution. The literature review identified another 63 published cases from 34 articles. Most cases were presented in the fifth to seventh decade of life with a male preponderance. Gingiva (23/69, 33.3%) was the most common site followed by the tongue (19/69, 27.5%) and buccal mucosa (8/69, 11.6%). Complete surgical ablation remains the primary treatment option. Tumor size, pathological grades, cervical node metastasis, and distant metastasis were significantly associated with reduced survival. Conclusions: Intraoral SpCC is an uncommon and aggressive malignancy with dismal prognosis. Much attention and effort are needed to characterize this rare entity and improve its clinical outcomes. [ABSTRACT FROM AUTHOR]

Transforming carbon dots (CDs) fluorescent materials into smart materials with complex functions is a topic of great interest to nanoscience. However, designing CDs with regulating fluorescence/phosphorescence that can be visually monitored with the environment changes in real‐time remains a challenge. Here, a very simple strategy, one‐step solvent‐free catalytic assistant strategy, which is low cost, facile, environment‐friendly, and high throughput, is put forward. Hydrogen bond is used to manipulate nanostructure of CDs, and the obtained carbon dots (M‐CDs) show a series of attractive properties including matrix‐free room‐temperature phosphorescence, time‐dependent fluorescence, and near‐infrared emissive characteristics. Different from the traditional aggregation caused quenching or aggregation‐induced emission fluorescent materials, M‐CDs exhibit unprecedented and unique dispersion induced redshift fluorescence phenomenon, promoting the studies of fluorescence from static to dynamic. The causes of this phenomenon are further analyzed in detail. As a kind of intelligent fluorescent materials, this new designed CDs greatly enrich the basic recognition of CDs by illustrating the relationship between redshift fluorescence behaviors and the dispersion states, and may provide with an opportunity for solid‐state fluorescent materials, anti‐counterfeiting, cellular imaging, and hopefully many others. [ABSTRACT FROM AUTHOR]

A new energy-loss analysis based on multifactor disturbance theory was studied in this paper. Due to the strong coupling characteristic of steam turbine system, the disturbance factors were decoupled and categorized. The main steam pressure, main steam temperature, reheat steam temperature and exhaust steam pressure were categorized as the large independent disturbance factors, while the terminal temperature differences (TTDs) of the regenerative heaters were categorized as small independent disturbance factors. The single-factor calculation method for energy-loss of heater TTDs neglected the interaction between each heater, thus all heater should be considered as a whole system when calculating the energy-loss of TTDs changes. The energy-loss of large independent disturbance was calculated based on global variable condition calculation method. Through calculating the energy-loss caused by the classified disturbance factors, the relative errors between the theoretical value and operation value were -3.00% for100%THA (turbine heat acceptance), -9.75 for 75%THA and 16.47% for 50%THA. The relative errors meet the requirements of the onsite guidance. [ABSTRACT FROM AUTHOR]