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1.
Small ; : e2401136, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38501858

RESUMO

High quality tin-lead perovskite solar cells (Sn─Pb PSCs) can be fabricated via simple solution processing methods. However, the instability of precursor solutions and their narrow usage windows still pose challenges in manufacturing efficient and reproducible Sn─Pb PSCs, hindering the commercialization of PSCs. Fluorine tin (SnF2 ) is widely used as an antioxidant to improve the crystallinity of perovskite. In this study, another role of SnF2 as a stabilizer is found to restrain the deprotonation of methylammonium iodide (MAI) in the precursor solution, which improves their stability and expands their usage windows. Due to the inhibition of SnF2 on oxidation and deprotonation, stable large-sized colloidal clusters form gradually in perovskite precursor solution during aging, leading to uniform nucleation/crystallization during film growth, significantly reducing the roughness and defect density in the films. Because of the competitive deprotonation and oxidation process of Sn2+ , the benefit of larger cluster maximizes after about ten days storage of precursor solution. The champion efficiency of Sn─Pb PSCs prepared with 10 days aged precursor solution is 22.00%. High performance of devices fabricated with precursor solution stored for even ≈40 days discloses the wide usage windows of precursor solution with SnF2 additive.

2.
Biochem Biophys Rep ; 35: 101532, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37637940

RESUMO

Changes in volatile metabolites during cigar tobacco leaves fermentation as well as the metabolic pathways of metabolites with significant differences were investigated to determine the influence of cigar tobacco leaves fermentation on its flavor. The volatile substances in cigar tobacco leaves at different stages were detected by headspace-solid phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS), and the main differences in volatile substances in cigar tobacco leaves at different fermentation stages of Yunxue1 in Yuxi production area were analyzed by principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA). The results show that in the process of cigar tobacco leaves fermentation (YXF0, YXF1, YXF2, YXF3, YXF4, YXF5), a total of 613 volatile metabolites were detected, and a significant difference was found in 263 kinds of metabolites. Among them, the main upregulated differential metabolites were 1,3,6,10-Cyclotetradecatetraene, 3,7,11-trimethyl-14-(1-methylethyl)-, [S-(E,Z,E,E)]-, Benzoic acid, Benzaldehyde, etc. While the main downregulated differential metabolites included beta.-Myrcene, trans-Farnesol, etc. The metabolites with significant differences are mainly concentrated in the biosynthesis of monoterpenes, diterpenes, sesquiterpenes and triterpenes, the degradation metabolism of amino acids, such as valine, leucine and isoleucine, and the biosynthesis of phenylpropyl. There were 8 different metabolites in 5 groups, including 4- (1-methylethyl) -1-cyclohexene-1-formaldehyde、2, 4-dihydroxyacetophenone、2-methylbutyl 3-methylbutyrate and methylpyrazine, all of which showed upregulation trend during fermentation. In the fermentation process, volatile metabolites participate in various synthesis and degradation pathways. The biosynthesis pathway of terpenes and amino acid synthesis and degradation pathway are connected to produce various terpenes, aldehydes and other substances, such as 1,3,6,10-Cyclotetradecatetraene, 3,7,11-trimethyl-14-(1-methylethyl)-, [S-(E,Z,E,E)]-、benzaldehyde and 4-hydroxybenzaldehyde, which are conducive to the overall flavor and quality of cigar tobacco leaves.

3.
Medicine (Baltimore) ; 102(52): e36022, 2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38206706

RESUMO

RATIONALE: Splenic B-cell lymphoma/leukemia with prominent nucleoli (SBLPN) is a new classification, which is so rare that it lacks clinical data. PATIENT CONCERNS: An increased proportion of prolymphocytes (84%) in the bone marrow smear. Whole exon sequence analysis revealed a TP53 mutation. DIAGNOSES: Combining the clinical features with laboratory test results led to a diagnosis of SBLPN which was made according to the 5th edition of the WHO classification of hematolymphoid tumors, although the patient was diagnosed with B-PLL when guided by the 4th edition of the WHO classification. INTERVENTIONS: The use of Ibrutinib as an effective treatment. OUTCOMES: The patient was in complete remission after 5 months of Ibrutinib and then died of sudden aortic dissection. LESSONS: Ibrutinib was an effective regimen for SBLPN. Aortic dissection might be considered as a suspicious adverse reaction to Ibrutinib.


Assuntos
Adenina/análogos & derivados , Dissecção Aórtica , Leucemia Linfocítica Crônica de Células B , Leucemia , Linfoma de Células B , Piperidinas , Humanos , Leucemia Linfocítica Crônica de Células B/patologia
4.
Anal Chim Acta ; 1214: 339939, 2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35649638

RESUMO

In current work, one novel benzothiazole-based fluorescent chemosensor (TZ-BO) with ESIPT luminescence mechanism was designed for the detection of hydrogen peroxide (H2O2) as typical reactive oxygen species (ROS). The boronate catenary in our designed probe molecule TZ-BO is both the blocking group of ESIPT and the reactive group of H2O2. The synthesized probe TZ-BO has the advantages of large Stokes shift, high sensitivity, good selectivity, and fast reaction speed to H2O2. The ability of the probe to detect H2O2 in aqueous media and exogenous H2O2 in cells by fluorescence signal was investigated. The experimental results manifested that probe TZ-BO is able to sensitively detect H2O2 using a fluorescence method in an excellent linear range of H2O2 concentration from 0 to 60 µM (R2 = 0.994). The detection limit was determined as 1.0 × 10-6 M. Most importantly, the probe TZ-BO with highly low cytotoxicity can effectively detect exogenous H2O2 in HeLa cells. This probe provides a promising tool for monitoring the real concentration level of H2O2 in related physiological and pathological researches.


Assuntos
Corantes Fluorescentes , Peróxido de Hidrogênio , Benzotiazóis , Células HeLa , Humanos , Limite de Detecção
5.
Colloids Surf B Biointerfaces ; 200: 111581, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33524696

RESUMO

Injectable thermosensitive hydrogel has been regarded as attractive drug delivery system, which displays a sol-gel phase transition upon injection in response to temperature. Recently, thermosensitive hydrogel has become a matter of importance in cancer therapy, providing high local drug concentration, sustained release characteristics, minimal invasiveness, and low systemic toxicities. Here, we review the extensive application of thermosensitive hydrogel in local cancer therapy, including chemotherapy, photothermal therapy, photodynamic therapy, gene therapy, chemo-photothermal combined therapy, and chemo-/immuno- combined therapy.


Assuntos
Hidrogéis , Neoplasias , Sistemas de Liberação de Medicamentos , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato , Hidrogéis/uso terapêutico , Injeções , Neoplasias/tratamento farmacológico , Temperatura
6.
J Food Sci ; 80(12): S2937-43, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26509667

RESUMO

Fermentation temperature strongly affects yeast metabolism during apple wine making and thus aromatic and quality profiles. In this study, the temperature effect during apple wine making on both the key aroma compounds and sensory properties of apple wine were investigated. The concentration of nine key aroma compounds (ethyl acetate, isobutyl acetate, isopentylacetate, ethyl caprylate, ethyl 4-hydroxybutanoate, isobutylalcohol, isopentylalcohol, 3-methylthio-1-propanol, and benzeneethanol) in apple wine significantly increased with the increase of fermentation temperature from 17 to 20 °C, and then eight out of the nine key aroma compounds with an exception of ethyl 4-hydroxybutanoate, decreased when the temperature goes up 20 to 26 °C. Sensory analysis showed that the apple wine fermented at 20 °C had the highest acceptance for consumers. Fermentation at the temperature of 20 °C was therefore considered to be the most suitable condition using the selected yeast strain (Saccharomyces cerevisiae AP05) for apple wine making. Changes in the fermentation temperature can considerably affect the production of key aroma compounds and sensory profiles of apple wine. These results could help apple wine producers make better quality production for consumers at the optimal fermentation temperature.


Assuntos
Fermentação , Frutas/metabolismo , Malus/química , Paladar , Temperatura , Compostos Orgânicos Voláteis/metabolismo , Vinho/análise , Frutas/microbiologia , Humanos , Odorantes , Saccharomyces cerevisiae/metabolismo
7.
Chem Commun (Camb) ; 49(81): 9248-50, 2013 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-23945650

RESUMO

Ambient temperature solid-state reaction of Pb(OAc)2 with TabHPF6 afforded an intermediate product [Pb(Tab)2]2(PF6)4, which further reacted with 4,4'-bipy in the solid state to generate a unique 2D cationic coordination polymer [Pb(Tab)2(4,4'-bipy)](PF6)2 in quantitative yield. Both complexes possess a low dielectric constant and low dielectric loss in the high electric field frequency range.

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