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1.
Nano Lett ; 24(4): 1406-1414, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38227806

RESUMO

The realization of high-Q single-mode lasing on the microscale is significant for the advancement of on-chip integrated light sources. It remains a challenging trade-off between Q-factor enhancement and light-field localization to raise the lasing emission rate. Here, we fabricated a zero-dimensional perovskite microcavity integrated with a nondamage pressed microlens to three-dimensionally tailor the intracavity light field and demonstrated linearly and nonlinearly (two-photon) pumped lasing by this microfocusing configuration. Notably, the microlensing microcavity experimentally achieves a high Q-factor (16700), high polarization (99.6%), and high Purcell factor (11.40) single-mode lasing under high-repetition pulse pumping. Three-dimensional light-field confinement formed by the microlens and plate microcavity simultaneously reduces the mode volume (∼3.66 µm3) and suppresses diffraction and transverse walk-off loss, which induces discretization on energy-momentum dispersions and spatial electromagnetic-field distributions. The Q factor and Purcell factor of our lasing come out on top among most of the reported perovskite microcavities, paving a promising avenue toward further studying electrically driven on-chip microlasers.

2.
Wei Sheng Yan Jiu ; 53(4): 600-607, 2024 Jul.
Artigo em Zh | MEDLINE | ID: mdl-39155228

RESUMO

OBJECTIVE: To analyze the nutrient composition and nutritional value evaluation of 5 potatoes in Anqing City. METHODS: According to the requirements of the Technical Manual for Food Composition Monitoring Projects, 5 types of potato samples were collected from Anqing City, Anhui Province. National standard detection method were used to determine the nutritional components such as water, ash, protein, fat, dietary fiber, sugar, minerals, vitamins, and amino acids in the samples. The index of nutritional quality(INQ) method was used to evaluate proteins, vitamins, and minerals, and the amino acid scoring standard mode(FAO/WHO mode) was used to evaluate the nutritional value of amino acids. RESULTS: Among the 5 types of potatoes, purple potato had the highest protein(2.3 g/100 g) and dietary fiber content(3.6 g/100 g). Sweet potato(red) had the highest carotene content(4003 µg/100 g), sweet potato(white) had the highest content of vitamin C(15.4 mg/100 g). Sugar in potatoes mainly existed in three forms: fructose, glucose, and sucrose; Purple potatoes had the highest levels of calcium(47 mg/100 g) and phosphorus(74 mg/100 g), respectively. Potatoes(white) had the highest content of potassium(401 mg/100 g), while sweet potatoes(red) had the highest content of magnesium(31 mg/100 g). Sodium(104.0 mg/100 g), iron(0.9 mg/100 g), copper(0.17 mg/100 g), and manganese(0.40 mg/100 g) had the highest content in sweet potatoes(white). The Na/K ratio range of the 5 potato varieties was 0.003-0.456, and the INQ of phosphorus, potassium, magnesium, copper, and manganese were greater than 1. The detection result of 5 potatoes all contain 18 amino acids, and aspartic acid was the highest. The amino acid score(AAS) was 0.29-1.35, and the ratio coefficient(RC) was 0.47-1.69. CONCLUSION: The 5 types of potatoes are rich in dietary fiber, vitamin C and minerals, and belong to the high potassium and low sodium type of food. Potatoes can meet the daily needs of the human body for phosphorus, potassium, magnesium copper, and manganese elements. Lysine is rich in content and can be used as a nutritional supplement for grains. The AAS score and RC are close to 1, and the AAS evaluation mode is closer to the human amino acid composition mode, which can meet the daily needs of the human body for this essential amino acid.


Assuntos
Fibras na Dieta , Minerais , Valor Nutritivo , Solanum tuberosum , Solanum tuberosum/química , Fibras na Dieta/análise , China , Minerais/análise , Vitaminas/análise , Análise de Alimentos , Aminoácidos/análise , Ácido Ascórbico/análise , Fósforo/análise
3.
Artigo em Inglês | MEDLINE | ID: mdl-33054532

RESUMO

Perfluoroisobutyronitrile (C4F7N) is a new eco-friendly gas insulation medium that has potential to replace the most greenhouse gas sulfur hexafluoride (SF6) used in power industry. In order to ensure the engineering application safety, an in-depth assessment of the acute inhalation toxicity of C4F7N gas mixture is required. This article revealed gender differences in male and female mice after exposure to C4F7N and the physiological recovery characteristics of surviving mice by means of 4 h acute inhalation toxicity tests, hematological determinations and histopathological examination. Comparative analysis on the toxicity of C4F7N on mice and rats is also evaluated. We find that the LC50 of C4F7N for male and female mice is 1175 ppm (4 h), 1380 ppm (4 h) and female ones are more tolerant to C4F7N. Mice that exposed to 1000 ppm C4F7N for 4 h could survive and return to their normal state after the 14-day observation period without irreversible damage. The toxic effect duration of C4F7N on rats is longer than that of mice. Relevant results revealed the acute inhalation toxicity of C4F7N systematically and provided fundamental reference for inhalation safety protection and engineering application.


Assuntos
Poluentes Atmosféricos/toxicidade , Gases/toxicidade , Exposição por Inalação/efeitos adversos , Nitrilas/toxicidade , Animais , Feminino , Gases de Efeito Estufa , Dose Letal Mediana , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Ratos , Hexafluoreto de Enxofre , Testes de Toxicidade Aguda
4.
Zhongguo Zhong Yao Za Zhi ; 45(7): 1545-1557, 2020 Apr.
Artigo em Zh | MEDLINE | ID: mdl-32489033

RESUMO

An ultra-performance liquid chromatography(UPLC) method integrating characteristic chromatogram and eight terpenoids determination has been established for comparing the differences of Alismatis Rhizoma(Zexie) from different product areas. Thirty-seven batches of crude drugs and thirty batches of prepared slices of Alismatis Rhizoma were analyzed. The obtained data were analyzed by similarity evaluation, principal components analysis(PCA) and partial least squares discriminant analysis(PLS-DA). There were three main characteristic peaks in the characteristic chromatograms, and alisol B 23-acetate(S) was selected as the reference. Compared with the S peak, the relative retention times of the other two characteristic peaks were 0.55(alisol) and 0.77(alisol B), respectively. Peak areas and the ratio of alisol B to alisol B 23-acetate could be used to distinguish Alismatis Rhizoma from different geographical origins. The samples were divided into three groups by PCA and PLS-DA based on the content determination results, and they were "Jian Zexie"(Fujian and Jiangxi provinces), "Chuan Zexie"(Sichuan and Hubei provinces), and "Guang Zexie"(Guangxi province). The contents of chemical components in samples from different producing areas were notably different. For example, the contents of alisol A and alisol A 24-acetate were significantly higher in "Guang Zexie" compared with "Jian Zexie" and "Chuan Zexie"(P<0.000 1). The contents of alisol B and alisol C were significantly higher in "Chuan Zexie" compared with "Jian Zexie"(P<0.000 1). Combining the characteristic chromatograms and quantitative analysis of eight terpenoids, this study showed that the relative contents of components and their ratios were notable different in samples from different regions, but types and numbers of chemical compositions were basically similar. The results of this study illustrated the regional differences of Alismatis Rhizoma and their components characteristics, and provided references for authentication and quality control of Alismatis Rhizoma.


Assuntos
Rizoma , China , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas , Terpenos
5.
Zhongguo Zhong Yao Za Zhi ; 45(7): 1566-1577, 2020 Apr.
Artigo em Zh | MEDLINE | ID: mdl-32489035

RESUMO

The present research was launched to improve the quality standards of Alismatis Rhizoma and supply scientific evidence and recommendations for the quality control of Alismatis Rhizoma in Chinese Pharmacopoeia(Ch. P) 2020 edition. The contents of water, total ash, heavy metals and deleterious element, pesticide residues and alcohol-soluble extract were analyzed according to the methods listed in the volume Ⅳ of Ch. P 2015 edition. Alisol B 23-acetate, alisol C 23-acetate and reference herbs were used to identify Alismatis Rhizoma by TLC method, which was developed by using a mixture of dichloromethane-methanol(15∶1) as developing solvent on silica gel GF_(254 )precoated plates. In HPLC method, alisol B 23-acetate and alisol C 23-acetate were separated with acetonitrile-water as the mobile phase and detected at 208 nm and 246 nm, respectively. Thirty-seven batches of crude drugs, thirty batches of prepared slices and nineteen batches of salt prepared slices of Alismatis Rhizoma were determined according to the methods established. The quality standards established based on the research results were specific and repeatable, and suitable for the quality evaluation of Alismatis Rhizoma. We recommended that the botanical sources, TLC examination, alcohol-soluble extract of salt prepared slices and content determination should be revised in the Ch. P 2020 edition.


Assuntos
Rizoma , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas , Controle de Qualidade
6.
Zhongguo Zhong Yao Za Zhi ; 45(7): 1558-1565, 2020 Apr.
Artigo em Zh | MEDLINE | ID: mdl-32489034

RESUMO

Ten compounds, including nucleosides and amino acids were identified by UPLC-Q-TOF-MS. HPLC fingerprints on these compounds in Alismatis Rhizoma were established for the first time. The comparisons of Alismatis Rhizoma from different regions were conducted by the similarity evaluation and hierarchical cluster analysis(HCA). Meanwhile, the HPLC-DAD method for the content determination of five nucleosides was also established. The results showed that the similarities of Alismatis Rhizoma collected from Sichuan and Fujian provinces were above 0.96, whereas they were less than 0.87 in those from Guangxi province. The results of HCA showed the samples from Sichuan and Fujian were gathered in the same group, all samples from Guangxi in another group, which indicated the similarities between samples from Sichuan and Fujian in nucleosides and they were different from the samples from Guangxi. The total contents of five nucleosides were revealed, of which samples from Sichuan and Fujian were 0.81-1.30 mg·g~(-1) followed a descending order of vernine>cytidine>uridine>adenine>adenosine, and from Guangxi were 0.35-0.50 mg·g~(-1) with the sequences of uridine>adenine>vernine>cytidine>adenosine. The nucleosides contents of samples from Sichuan and Fujian were both higher than that from Guangxi. For samples from Sichuan and Fujian, the former was slightly higher, except for adenine. These results would be helpful to reveal the bioactive constituents in aqueous extract and provided important evidences for the quality control of Alismatis Rhizoma.


Assuntos
Medicamentos de Ervas Chinesas , China , Cromatografia Líquida de Alta Pressão , Nucleosídeos , Rizoma
7.
Zhongguo Zhong Yao Za Zhi ; 45(7): 1578-1595, 2020 Apr.
Artigo em Zh | MEDLINE | ID: mdl-32489036

RESUMO

Alismatis Rhizoma is a traditional Chinese medicine, which was widely used in clinical prescriptions and proprietary Chinese medicine. Over 220 compounds have been isolated from it, including triterpenoids, sesquiterpenoids, diterpenoids, polysaccharides, nitrogen compounds, phenylpropanoids, flavones and sterides. The pharmacological studies show that Alismatis Rhizoma exhibits diuretic, anti-urolithiatic, anti-hyperlipidemia, antidiabetics, antitumor, antioxidative, anti-inflammatory, anti-complementary activities, etc. In this review, the chemical compositions and its pharmacological activities of Alismatis Rhizoma in recent 50 years were summarized. The authors hope to provide references for further study, development and utilization of Alismatis Rhizoma.


Assuntos
Rizoma , Diuréticos , Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Triterpenos
8.
Zhongguo Zhong Yao Za Zhi ; 45(8): 1734-1744, 2020 Apr.
Artigo em Zh | MEDLINE | ID: mdl-32489056

RESUMO

In order to provide scientific recommendations for the revision of the quality standards of Poria in Chinese Pharmacopoeia(Ch. P) 2020 edition, a series of experiments were carried out to improve the quality standards of Poria. TLC methods were established to identify Poria by using pachymic acid, dehydrotumulosic acid and reference herbs as reference substances. The contents of water, total ash, pesticide residues, heavy metals and deleterious element, mycotoxins, sulfur dioxide residues and ethanol-soluble extract of herbal materials and decoction pieces of Poria were determined according to the methods recorded in the volume Ⅳ of Ch. P 2015 edition. An HPLC method was developed for the determination of pachymic acid and dehydropachymic acid. The contents of polysaccharide were determined by spectrophotometry using D-glucose as reference substance. The quality standards were established on the basis of the research results, in which the [assay] were added, and the [identification] and [tests] were revised when compared with Ch. P 2015 edition. The established methods are simple, specific, repeatable, and suitable for the quality evaluation of Poria.


Assuntos
Medicamentos de Ervas Chinesas , Poria , Cromatografia Líquida de Alta Pressão , Padrões de Referência
9.
Zhongguo Zhong Yao Za Zhi ; 44(7): 1371-1380, 2019 Apr.
Artigo em Zh | MEDLINE | ID: mdl-31090294

RESUMO

HPLC specific chromatograms of Poria were established, and the concentrations of 10 triterpenoids(16α-hydroxydehydrotrametenolic acid, poricoic acid B, dehydrotumulosic acid, poricoic acid A, polyporenic acid C, poricoic acid AM, 3-O-acetyl-16α-hydroxydehydrotrametenolic acid, dehydropachymic acid, pachymic acid, and dehydrotrametenolic acid) were simultaneously determined. Chromatographic analysis was conducted on a Welch Ultimate XB C_(18) column(4.6 mm × 250 mm,5 µm). Acetonitrile solution(contain 3% tetrahydrofuran)(A) and 0.1% formic acid aqueous solution(B) were used as the mobile phase with gradient elution at a flow rate of 1.0 mL·min~(-1). The column temperature was 30 ℃ and the injection volume was 20 µL. The experimental data were analyzed by the SPSS 22.0 and GraphPad Prism 7.0. The established triterpenoids fingerprints were specific, and the 10 components were well separated and showed good linearity(r≥0.999 6) within the concentration ranges tested. The mean recoveries were between 98.53%-103.8%(RSD 1.7%-2.7%). The method was specific and repeatable, and could be used for identification and quality evaluation of Poria. The results showed that the contents of 10 triterpenoids were positively correlated with each other. The contents of 10 triterpenoids of samples collected from producing areas were higher than that collected from markets. The total contents of 10 triterpenoids of samples collected from Hubei and Yunnan province were slightly higher than that from Anhui province, but the contents of samples from Anhui province were varied in smaller ranges.


Assuntos
Materia Medica/análise , Poria/química , China , Cromatografia Líquida de Alta Pressão
10.
Environ Sci Technol ; 51(17): 10127-10136, 2017 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-28749654

RESUMO

SF6, the most widely used electrical-equipment-insulation gas, has serious greenhouse effects. C5F10O has attracted much attention as an alternative gas in recent two years, but the environmental impact of its decomposition products is unclear. In this work, the decomposition characteristics of C5F10O were studied based on gas chromatography-mass spectrometry and density functional theory. We found that the amount of decomposition products of C5F10O, namely, CF4, C2F6, C3F6, C3F8, C4F10, and C6F14, increased with increased number of discharges. Under a high-energy electric field, the C-C bond of C5F10O between carbonyl carbon and α-carbon atoms was most likely to break and generate CF3CO•, C3F7• or C3F7CO•, CF3• free radicals. CF3•, and C3F7• free radicals produced by the breakage more easily recombined to form small molecular products. By analyzing the ionization parameters, toxicity, and environmental effects of C5F10O and its decomposition products, we found that C5F10O gas mixtures exhibit great decomposition and environmental characteristics with low toxicity, with great potential to replace SF6.


Assuntos
Carbono , Efeito Estufa , Clima , Cromatografia Gasosa-Espectrometria de Massas , Gases
11.
Int J Sport Nutr Exerc Metab ; 27(1): 50-58, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27206023

RESUMO

OBJECTIVE: This study aimed to investigate the relationship between metabolic syndrome (MetS) and physical activity (PA) in different domains among male coal miners of Shanxi Province in China. METHOD: The study was conducted from July 2013 to December 2013. A two-stage stratified cluster sampling method was used. Data regarding the general information of participants were collected by well-trained interviewers. MetS was defined according to IDF criteria. Self-reported PA was obtained with the IPAQ and categorized into three tertiles of intensity levels across occupation, transportation, household, and leisure-time domains. Univariate and multiple logistic regression analysis were applied to compute the odds ratios and their 95% confidence interval (CI). RESULTS: A total of 3076 males aged 18-65 years old were recruited in this cross-sectional study. The prevalence of MetS was 40.5% in the study subjects. The percentages of vigorous-intensity PA in MetS and non-MetS groups were 70.07% and 62.92%, respectively. Participants spent most of their time on occupation (2034 MET-min/w) and transportation (693MET-min/w) domains. Higher-intensity levels in occupation domains were significantly associated with lower risk of MetS (OR: 0.759, 95% CI: 0.633-0.911; OR: 0.627, 95% CI: 0.516-0.762). CONCLUSIONS: Across four types of workers, the relationships between PA domains and MetS were different. For underground and underground auxiliary workers, the negative relationship was found between occupation PA and MetS. For office workers, the negative relationship was found between household PA and MetS. For ground workers, only leisure-time PA had positively related to MetS.


Assuntos
Exercício Físico , Síndrome Metabólica/epidemiologia , Mineradores , Adolescente , Adulto , Idoso , China , Análise por Conglomerados , Minas de Carvão , Estudos Transversais , Humanos , Masculino , Síndrome Metabólica/diagnóstico , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Tamanho da Amostra , Fatores Socioeconômicos , Inquéritos e Questionários , Adulto Jovem
12.
Sci Total Environ ; 916: 170271, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38262248

RESUMO

The global warming and other environmental problems caused by SF6 emissions can be reduced due to the widespread use of eco-friendly insulating gas, perfluoropentanone (C5F10O). However, there is an exposure risk to populations in areas near C5F10O equipment, so it is important to clarify its biosafety and pathogenesis before large-scale application. In this paper, histopathology, transcriptomics, 4D-DIA proteomics, and LC-MS metabolomics of rats exposed to 2000 ppm and 6000 ppm C5F10O are analyzed to reveal the mechanisms of toxicity and health risks. Histopathological shows that inflammatory cell infiltration, epithelial cell hyperplasia, and alveolar atrophy accompanied by alveolar wall thickening are present in both low-dose and high-dose groups. Analysis of transcriptomic and 4D-DIA proteomic show that Cell cycle and DNA replication can be activated by both 2000 ppm and 6000 ppm C5F10O to induce cell proliferation. In addition, it also leads to the activation of pathways such as Antigen processing and presentation, Cell adhesion molecules and Complement and coagulation cascades, T cell receptor signal path, Th1 and T cell receptor signal path, Th1 and Th2 cell differentiation, complement and coagulation cascades. Finally, LC-MS metabolomics analysis confirms that the metabolic pathways associated with glycerophospholipids, arachidonic acid, and linoleic acid are disrupted and become more severe with increasing doses. The mechanism of lung toxicity caused by C5F10O is systematically expounded based on the multi-omics analysis and provided biosafety references for further promotion and application of C5F10O.


Assuntos
Pneumopatias , Proteômica , Ratos , Animais , Pulmão , Receptores de Antígenos de Linfócitos T
13.
Food Chem ; 448: 139162, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38579557

RESUMO

Carbon nitride nanoflower materials (CNNFs) modified electrodes were prepared and used as electrochemiluminescence (ECL) sensors for the sensitive detection of melatonin (MT) in food. The luminescence intensity of CNNFs is increased by 4.6 times compared with bulk g-C3N4. In addition, the effect of dissolved oxygen on the material was eliminated, and the stability of ECL intensity of CNNFs was improved. Under the optimal experimental conditions, there is a good linear relationship between the ECL intensity ratio and logCMT in a concentration range of 2.0 × 10-11-1.0 × 10-6 mol/L, and the detection limit is 6.2 × 10-13 mol/L. This experiment has been successfully used for the detection of MT in rice, black rice, oats, apples, bananas, grapes, carrots, tomatoes, cucumbers, bread, and beers. The results are consistent with those obtained by high-performance liquid chromatography (HPLC). Therefore, this sensor is a sensitive and effective method for detecting MT content in food.

14.
Int J Antimicrob Agents ; 63(2): 107062, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38104947

RESUMO

BACKGROUND: Tigecycline has been widely used for multi-drug-resistant bacterial infections in China. Although many studies have reported the risk factors for tigecycline-induced hypofibrinogenaemia, it remains unknown whether valproic acid or voriconazole in combination with tigecycline is associated with the decrease in fibrinogen, as both drugs could lead to coagulation disorders. The aim of this study was to develop a nomogram for the prediction of tigecycline-induced hypofibrinogenaemia. METHODS: This was a multi-centre retrospective case-control study. The primary outcome was the accurate prediction of tigecycline-induced hypofibrinogenaemia. Nomograms were developed from logistic regression models with least absolute shrinkage and selection operator regression for variable selection. Model performance was assessed via calibration plots, and models were validated internally using bootstrapping on a validation cohort. RESULTS: In total, 2362 patients were screened, of which 611 were eligible for inclusion in this study. These 611 patients were divided into the training cohort (n=488) and the validation cohort (n=123). Predictors included in the nomogram for the total population were total dose, age, fibrinogen, prothrombin time (PT), comorbidity, and concomitant use of voriconazole. Total dose, fibrinogen, PT, activated partial thromboplastin time, white blood cell count, and concomitant use of voriconazole were selected to predict hypofibrinogenaemia in patients with malignant haematologic diseases. Both models were calibrated adequately, and their predictions were correlated with the observed outcome. The cut-offs for treatment duration in the total population and the subgroup were 10 and 6 days, respectively. CONCLUSIONS: Tigecycline in combination with voriconazole could increase the risk of hypofibrinogenaemia, and tigecycline-induced hypofibrinogenaemia is more likely to occur in patients with malignant haematologic diseases.


Assuntos
Afibrinogenemia , Nomogramas , Humanos , Tigeciclina/uso terapêutico , Afibrinogenemia/tratamento farmacológico , Estudos Retrospectivos , Estudos de Casos e Controles , Voriconazol , Fibrinogênio
15.
Nat Commun ; 15(1): 1536, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38378620

RESUMO

The development of highly efficient active integrated photonic circuits is crucial for advancing information and computing science. Lead halide perovskite semiconductors, with their exceptional optoelectronic properties, offer a promising platform for such devices. In this study, active micro multifunctional photonic devices were fabricated on monocrystalline CsPbBr3 perovskite thin films using a top-down etching technique with focused ion beams. The etched microwire exhibited a high-quality micro laser that could serve as a light source for integrated devices, facilitating angle-dependent effective propagation between coupled perovskite-microwire waveguides. Employing this strategy, multiple perovskite-based active integrated photonic devices were realized for the first time. These devices included a micro beam splitter that coherently separated lasing signals, an X-coupler performing transfer matrix functions with two distinguishable light sources, and a Mach-Zehnder interferometer manipulating the splitting and coalescence of coherent light beams. These results provide a proof-of-concept for active integrated functionalized photonic devices based on perovskite semiconductors, representing a promising avenue for practical applications in integrated optical chips.

16.
Adv Mater ; : e2314380, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38517171

RESUMO

Triboelectric nanogenerator (TENG) manifests distinct advantages such as multiple structural selectivity, diverse selection of materials, environmental adaptability, low cost, and remarkable conversion efficiency, which becomes a promising technology for micro-nano energy harvesting and self-powered sensing. Tribo-dielectric materials are the fundamental and core components for high-performance TENGs. In particular, the charge generation, dissipation, storage, migration of the dielectrics, and dynamic equilibrium behaviors determine the overall performance. Herein, a comprehensive summary is presented to elucidate the dielectric charge transport mechanism and tribo-dielectric material modification principle toward high-performance TENGs. The contact electrification and charge transport mechanism of dielectric materials is started first, followed by introducing the basic principle and dielectric materials of TENGs. Subsequently, modification mechanisms and strategies for high-performance tribo-dielectric materials are highlighted regarding physical/chemical, surface/bulk, dielectric coupling, and structure optimization. Furthermore, representative applications of dielectric materials based TENGs as power sources, self-powered sensors are demonstrated. The existing challenges and promising potential opportunities for advanced tribo-dielectric materials are outlined, guiding the design, fabrication, and applications of tribo-dielectric materials.

17.
ACS Omega ; 8(31): 28769-28777, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37576628

RESUMO

The detection of sulfur hexafluoride (SF6) decomposition components has become one of the best ways to diagnose early latent insulation faults in gas-insulated equipment, which can effectively prevent sudden accidents by identifying such faults. In this paper, we by first-principles theory investigated the adsorption and sensing behaviors of four typical SF6 decomposition components (H2S, SO2, SOF2, and SO2F2) on the pristine Pd-doped MoTe2 monolayer. The adsorption energy, work function, recovery time, charge density difference, density of state, and band structure of the adsorption structures are obtained as well as analyzed. The results indicate that the Pd dopant prefers to be trapped at the TMo site, with a binding energy of -2.25 eV. The Pd-MoTe2 chemisorbs the remaining gases except SO2xF2, with the adsorption capacity ranking as SOF2 > SO2 > H2S. The adsorption of gas molecules reduces the bandgap of Pd-MoTe2, thereby increasing conductivity. On the other hand, the recovery time of the Pd-MoTe2 monolayer material at a temperature of 398 K demonstrates its excellent gas desorption performance toward four decomposition gases. The research results provide a theoretical basis for Pd-MoTe2 to detect SF6 decomposition components, thus, promoting the stable operation of the power system.

18.
Front Pharmacol ; 14: 1182644, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37351509

RESUMO

Background: Tigecycline and cefoperazone/sulbactam can cause coagulation disorders; tigecycline may also lead to hypofibrinogenemia, raising safety concerns. This study aimed to investigate whether tigecycline plus cefoperazone/sulbactam increases the risk of bleeding compared with other tigecycline-based combination therapies and identify risk factors for tigecycline-associated hypofibrinogenemia. Methods: In this multi-method, multicenter, retrospective study, coagulation and other baseline variables were compared using a cohort study, and risk factors for hypofibrinogenemia using a case-control study. Results: The 451 enrolled participants were divided into three group: tigecycline plus cefoperazone/sulbactam (Group A, 193 patients), tigecycline plus carbapenems (Group B, 200 patients) and tigecycline plus ß-lactams without N-methylthio-tetrazole (NMTT) side chains (Group C, 58 patients). Activated partial thromboplastin time and prothrombin time were prolonged, and fibrinogen declined for all patients after tigecycline-based medication (all p < 0.05). Prothrombin time in Group B was significantly longer than in other groups (p < 0.05), but there were no significant differences in bleeding events between the three groups (p = 0.845). Age greater than 80 years (OR: 2.85, 95% CI: 1.07-7.60), treatment duration (OR: 1.29, 95% CI: 1.19-1.41), daily dose (OR: 2.6, 95% CI: 1.29-5.25), total bilirubin (OR: 1.01, 95% CI: 1.01-1.02) and basal fibrinogen (OR: 1.32, 95% CI: 1.14-1.63) were independent risk factors of hypofibrinogenemia. The optimal cut-off for treatment course was 6 days for high-dose and 11 days for low-dose. Conclusion: Tigecycline plus cefoperazone/sulbactam did not increase the risk of bleeding compared with tigecycline plus carbapenem, or tigecycline plus ß-lactam antibiotics without NMTT-side-chains. Coagulation function should be closely monitored in patients receiving tigecycline treatment.

19.
Diabetes Metab Syndr Obes ; 16: 385-395, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36816816

RESUMO

Purpose: In-depth investigations of risk factors for the identification of diabetic kidney disease (DKD) in type 2 diabetes mellitus (T2DM) are rare. We aimed to investigate the risk factors for developing DKD from multiple types of clinical data and conduct a comprehensive risk assessment for individuals with diabetes. Methods: We carried out a case-control study, enrolling 958 patients to identify the risk factors for developing DKD in T2DM patients from a database established from inpatient electronic medical records. Multivariable logistic regression was applied to develop a prediction model and the performance of the model was evaluated using the area under the curve (AUC) and calibration curve. A multifactorial risk score system was established according to the Framingham Study risk score. Results: DKD accounted for 34.03% of eligible patients in total. Twelve risk factors were selected in the final prediction model, including age, duration of diabetes, duration of hypertension, fasting blood glucose, fasting C-peptide, insulin use, systolic blood pressure, low-density lipoprotein, γ-glutamyl transpeptidase, platelet, uric acid, and thyroid stimulating hormone; and one protective factor, serum albumin. The prediction model showed an AUC of 0.862 (95% Confidence Interval (CI) 0.834-0.890) with an accuracy of 81.5% in the derivation dataset and an AUC of 0.876 (95% CI 0.825-0.928) in the validation dataset. The calibration curves were excellent and the estimated probability of DKD was more than 80% when the cumulative score for risk factors reached 17 points. Conclusion: Newly recognized risk factors were applied to assess the development of DKD in T2DM patients and the established risk score system was a reliable and feasible tool for assisting clinicians to identify patients at high risk of DKD.

20.
Adv Mater ; 35(19): e2210594, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36859570

RESUMO

Orientational growth of single-crystalline structures is pivotal in the semiconductor industry, which is achievable by epitaxy for producing thin films, heterostructures, quantum wells, and superlattices. Beyond silicon and III-V semiconductors, solution-processible semiconductors, such as metal-halide perovskites, are emerging for scalable and cost-effective manufacture of optoelectronic devices, whereas the polycrystalline nature of fabricated structures restricts their application toward integrated devices. Here, electrostatic epitaxy, a process sustained by strong electrostatic interactions between self-assembled surfactants (octanoate anions) and Pb2+ , is developed to realize orientational growth of single-crystalline CsPbBr3 microwires. Strong electrostatic interactions localized at the air-liquid interface not only support preferential nucleation for single crystallinity, but also select the crystal facet with the highest Pb2+ areal density for pure crystallographic orientation. Due to the epitaxy at the air-liquid interface, direct growth of oriented single-crystalline microwires onto different substrates without the processes of lift-off and transfer is realized. Photonic lasing emission, waveguide coupling, and on-chip propagation of coherent light are demonstrated based on these single-crystalline microwires. These findings open an avenue for on-chip integration of single-crystalline materials.

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