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1.
Cardiovasc Diabetol ; 23(1): 86, 2024 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-38419039

RESUMO

BACKGROUND: Studies on the relationship between insulin resistance (IR) surrogates and long-term all-cause mortality in patients with coronary heart disease (CHD) and hypertension are lacking. This study aimed to explore the relationship between different IR surrogates and all-cause mortality and identify valuable predictors of survival status in this population. METHODS: The data came from the National Health and Nutrition Examination Survey (NHANES 2001-2018) and National Death Index (NDI). Multivariate Cox regression and restricted cubic splines (RCS) were performed to evaluate the relationship between homeostatic model assessment of IR (HOMA-IR), triglyceride glucose index (TyG index), triglyceride glucose-body mass index (TyG-BMI index) and all-cause mortality. The recursive algorithm was conducted to calculate inflection points when segmenting effects were found. Then, segmented Kaplan-Meier analysis, LogRank tests, and multivariable Cox regression were carried out. Receiver operating characteristic (ROC) and calibration curves were drawn to evaluate the differentiation and accuracy of IR surrogates in predicting the all-cause mortality. Stratified analysis and interaction tests were conducted according to age, gender, diabetes, cancer, hypoglycemic and lipid-lowering drug use. RESULTS: 1126 participants were included in the study. During the median follow-up of 76 months, 455 participants died. RCS showed that HOMA-IR had a segmented effect on all-cause mortality. 3.59 was a statistically significant inflection point. When the HOMA-IR was less than 3.59, it was negatively associated with all-cause mortality [HR = 0.87,95%CI (0.78, 0.97)]. Conversely, when the HOMA-IR was greater than 3.59, it was positively associated with all-cause mortality [HR = 1.03,95%CI (1.00, 1.05)]. ROC and calibration curves indicated that HOMA-IR was a reliable predictor of survival status (area under curve = 0,812). No interactions between HOMA-IR and stratified variables were found. CONCLUSION: The relationship between HOMA-IR and all-cause mortality was U-shaped in patients with CHD and hypertension. HOMA-IR was a reliable predictor of all-cause mortality in this population.


Assuntos
Doença das Coronárias , Hipertensão , Resistência à Insulina , Humanos , Estudos Longitudinais , Inquéritos Nutricionais , Glicemia , Estudos de Coortes , Hipertensão/diagnóstico , Doença das Coronárias/diagnóstico , Triglicerídeos , Glucose , Biomarcadores
2.
Front Cardiovasc Med ; 11: 1308592, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38327493

RESUMO

Background: The relationship between sleep characteristics and cardiovascular disease (CVD) risk has yet to reach a consistent conclusion, and more research needs to be carried out. This study aimed to explore the relationship between snoring, daytime sleepiness, bedtime, sleep duration, and high-risk sleep patterns with CVD risk. Methods: Data from the National Health and Nutrition Examination Survey (NHANES) 2015-2018 were collected and analyzed. Multivariable logistic regression was used to evaluate the relationship between snoring, daytime sleepiness, bedtime, sleep duration, high-risk sleep patterns, and CVD risk. Stratified analysis and interaction tests were carried out according to hypertension, diabetes and age. Results: The final analysis contained 6,830 participants, including 1,001 with CVD. Multivariable logistic regression suggested that the relationship between snoring [OR = 7.37,95%CI = (6.06,8.96)], daytime sleepiness [OR = 11.21,95%CI = (9.60,13.08)], sleep duration shorter than 7 h [OR = 9.50,95%CI = (7.65,11.79)] or longer than 8 h [OR = 6.61,95%CI = (5.33,8.19)], bedtime after 0:00 [OR = 13.20,95%CI = (9.78,17.80)] compared to 22:00-22:59, high-risk sleep patterns [OR = 47.73,95%CI = (36.73,62.04)] and CVD risk were statistically significant. Hypertension and diabetes interacted with high-risk sleep patterns, but age did not. Conclusions: Snoring, daytime sleepiness, excessive or short sleep duration, inappropriate bedtime, and high-risk sleep patterns composed of these factors are associated with the CVD risk. High-risk sleep patterns have a more significant impact on patients with hypertension and diabetes.

3.
Small ; 20(3): e2305539, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37699754

RESUMO

Artificial enzymes, as alternatives to natural enzymes, have attracted enormous attention in the fields of catalysis, biosensing, diagnostics, and therapeutics because of their high stability and low cost. Polyoxometalates (POMs), a class of inorganic metal oxides, have recently shown great potential in mimicking enzyme activity due to their well-defined structure, tunable composition, high catalytic efficiency, and easy storage properties. This review focuses on the recent advances in POM-based artificial enzymes. Different types of POMs and their derivatives-based mimetic enzyme functions are covered, as well as the corresponding catalytic mechanisms (where available). An overview of the broad applications of representative POM-based artificial enzymes from biosensing to theragnostic is provided. Insight into the current challenges and the future directions for POMs-based artificial enzymes is discussed.


Assuntos
Ânions , Polieletrólitos , Ânions/química , Polieletrólitos/química , Enzimas
4.
BMJ Open ; 13(9): e074067, 2023 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-37723117

RESUMO

INTRODUCTION: Coronary heart disease (CHD) is one of the common cardiovascular diseases that seriously jeopardise human health, and endothelial inflammation and dyslipidaemia are the initiating links leading to its occurrence. Percutaneous coronary intervention (PCI) is one of the most effective surgical treatments for CHD with narrowed or blocked blood vessels, which can quickly unblock the blocked vessels and restore coronary blood supply. However, most patients may experience coronary microcirculation disorders (CMDs) and decreased cardiac function after PCI treatment, which directly affects the efficacy of PCI and the prognosis of patients. Preprotein converting enzyme subtilisin/Kexin 9 (PCSK9) inhibitors are novel pleiotropy lipid-lowering drug with dual anti-inflammation and lipid-lowering effects, and represent a new clinical pathway for rapid correction of dyslipidaemia. Therefore, we designed this protocol to systematically evaluate the effects of PCSK9 inhibitors on coronary microcirculation and cardiac function in patients with CHD after PCI, and to provide high-quality evidence-based evidence for the clinical application of PCSK9 inhibitors. METHODS AND ANALYSIS: This protocol is reported strictly in accordance with the 2020 Preferred Reporting Items for Systematic Reviews and Meta-analyses Protocols Guidelines. We will search PubMed, EMBASE, Web of Science and three Chinese databases (CNKI, Wanfang and VIP database) according to preset search strategies, without language and publication data restrictions. We will work with manual retrieval to screen references that have been included in the literature. Google Scholar will be used to search for grey literature. The final included literature must meet the established inclusion criteria. Titles, abstracts and full text will be extracted independently by two reviewers, and disagreements will be resolved through discussion or the involvement of a third reviewer. Extracted data will be analysed using Review Manager V.5.3. The Cochrane Risk of Bias Tool will be used to evaluate the risk of bias. Publication bias will be assessed by funnel plots. Heterogeneity will be assessed by I2 test and subgroup analyses will be used to further investigate potential sources of heterogeneity. The quality of the literature will be assessed by GRADE score. This protocol will start in January 2026 and end in December 2030. ETHICS AND DISSEMINATION: This study is a systematic review of published literature data and no special ethical approval was required. PROSPERO REGISTRATION NUMBER: CRD42022346189.


Assuntos
Doença das Coronárias , Intervenção Coronária Percutânea , Humanos , Subtilisina , Inibidores de PCSK9 , Pró-Proteína Convertase 9 , Microcirculação , Revisões Sistemáticas como Assunto , Metanálise como Assunto , Inflamação , Inibidores Enzimáticos , Lipídeos
5.
Plant Physiol ; 193(2): 1527-1546, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37432453

RESUMO

In the Rhizobium-Legume symbiosis, the nodulation outer protein P (NopP) effector is one of the key regulators for rhizobial infection and nodule organogenesis. However, the molecular mechanism through which host legume plants sense NopP remains largely unknown. Here, we constructed an nopP deletion mutant of Mesorhizobium huakuii and found that nopP negatively regulates nodulation on Chinese milk vetch (Astragalus sinicus). Screening for NopP interacting proteins in host plants using the yeast 2-hybrid system identified NopP interacting protein 43 (AsNIP43), which encodes a G-type receptor-like kinase (LecRLK). The B-lectin domain at the N terminus of AsNIP43 was essential in mediating its interaction with NopP, which was confirmed in vitro and in vivo. Subcellular localization, co-localization, and gene expression analyses showed that AsNIP43 and NopP function tightly associated with earlier infection events. RNA interference (RNAi) knockdown of AsNIP43 expression by hairy root transformation led to decreased nodule formation. AsNIP43 plays a positive role in symbiosis, which was further verified in the model legume Medicago truncatula. Transcriptome analysis indicated that MtRLK (a homolog of AsNIP43 in M. truncatula) may function to affect defense gene expression and thus to regulate early nodulation. Taken together, we show that LecRLK AsNIP43 is a legume host target that interacts with rhizobia effector NopP is essential for rhizobial infection and nodulation.


Assuntos
Astrágalo , Medicago truncatula , Rhizobium , Simbiose/genética , Nodulação/genética , Fenótipo , Proteínas de Transporte/genética , Medicago truncatula/genética , Rhizobium/fisiologia
6.
ACS Appl Mater Interfaces ; 15(29): 34497-34504, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37439628

RESUMO

Prion disorders are a group of lethal infectious neurodegenerative diseases caused by the spontaneous aggregation of misfolded prion proteins (PrPSc). The oxidation of such proteins by chemical reagents can significantly modulate their aggregation behavior. Herein, we exploit a series of vanadium-substituted Keggin-type tungsten and molybdenum POMs (W- and Mo-POMs) as chemical tools to oxidize PrP106-126 (denoted as PrP), an ideal model for studying PrPSc. Due to the band gaps being larger than that of Mo-POMs, W-POMs possess higher structural stability and show stronger binding and oxidation effect on PrP. Additionally, the substitution of W/Mo by vanadium elevates the local electron distribution on the bridged O(26) atom, thereby strengthening the hydrogen bonding of POMs with the histidine site. Most importantly, with the number of substituted vanadium increases, the LUMO energy level of POMs decreases, making it easier to accept electrons from methionine. As a result, PW10V2 displays the strongest oxidation on the methionine residue of PrP, leading to an excellent inhibitory effect on PrP aggregation and a significant attenuation on its neurotoxicity.


Assuntos
Proteínas Priônicas , Príons , Príons/química , Príons/metabolismo , Vanádio , Metionina/química , Racemetionina
7.
Small ; 19(24): e2207315, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36929209

RESUMO

Polyoxometalates (POMs) are widely used in catalysis, energy storage, biomedicine, and other research fields due to their unique acidity, photothermal, and redox features. However, the leaching and agglomeration problems of POMs greatly limit their practical applications. Confining POMs in a host material is an efficient tool to address the above-mentioned issues. POM@host materials have received extensive attention in recent years. They not only inherent characteristics of POMs and host, but also play a significant synergistic effect from each component. This review focuses on the recent advances in the development and applications of POM@host materials. Different types of host materials are elaborated in detail, including tubular, layered, and porous materials. Variations in the structures and properties of POMs and hosts before and after confinement are highlighted as well. In addition, an overview of applications for the representative POM@host materials in electrochemical, catalytic, and biological fields is provided. Finally, the challenges and future perspectives of POM@host composites are discussed.

8.
Microbiol Spectr ; 11(1): e0335022, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36633436

RESUMO

Rhizobia can infect legumes and induce the coordinated expression of symbiosis and defense genes for the establishment of mutualistic symbiosis. Numerous studies have elucidated the molecular interactions between rhizobia and host plants, which are associated with Nod factor, exopolysaccharide, and T3SS effector proteins. However, there have been relatively few reports about how the host plant recognizes the outer membrane proteins (OMPs) of rhizobia to mediate symbiotic nodulation. In our previous work, a gene (Mhopa22) encoding an OMP was identified in Mesorhizobium huakuii 7653R, whose homologous genes are widely distributed in Rhizobiales. In this study, a germin-like protein GLP1 interacting with Mhopa22 was identified in Astragalus sinicus. RNA interference of AsGLP1 resulted in a decrease in nodule number, whereas overexpression of AsGLP1 increased the number of nodules in the hairy roots of A. sinicus. Consistent symbiotic phenotypes were identified in Medicago truncatula with MtGLPx (refer to medtr7g111240.1, the isogeny of AsGLP1) overexpression or Tnt1 mutant (glpx-1) in symbiosis with Sinorhizobium meliloti 1021. The glpx-1 mutant displayed hyperinfection and the formation of more infection threads but a decrease in root nodules. RNA sequencing analysis showed that many differentially expressed genes were involved in hormone signaling and symbiosis. Taken together, AsGLP1 and its homology play an essential role in mediating the early symbiotic process through interacting with the OMPs of rhizobia. IMPORTANCE This study is the first report to characterize a legume host plant protein to sense and interact with an outer membrane protein (OMP) of rhizobia. It can be speculated that GLP1 plays an essential role to mediate early symbiotic process through interacting with OMPs of rhizobia. The results provide deeper understanding and novel insights into the molecular interactive mechanism of a legume symbiosis signaling pathway in recognition with rhizobial OMPs. Our findings may also provide a new perspective to improve the symbiotic compatibility and nodulation of legume.


Assuntos
Medicago truncatula , Rhizobium , Proteínas de Membrana/metabolismo , Simbiose , Rhizobium/metabolismo , Raízes de Plantas/metabolismo , Proteínas de Plantas/genética , Medicago truncatula/genética , Medicago truncatula/metabolismo
9.
Toxicol Mech Methods ; 32(1): 27-36, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34412561

RESUMO

The effect of Pulsatilla saponin A (PsA) on acute myocardial infarction (AMI) was unknown. This study targeted to examine the roles of PsA on hypoxia-triggered toxicity to H9c2 cells and reveal the potential mechanism. H9c2 cells were maintained under a hypoxic environment for 12 h to construct the AMI cell model and the cells were pretreated by PsA. Hypoxia triggered toxicity to H9c2 cells and the anti-toxicity effect of PsA was evaluated by CCK8, TUNEL, and Western blot. The levels of miR-24-3p and p16 in H9c2 cells, AMI group tissues, and their respective controls were assessed using qRT-PCR. The dual-luciferase assay was applied to verify the targeting mechanism of miR-24-3p on p16. Then the effects of miR-24-3p inhibitor or/and si-p16 on H9c2 cells treated with PsA under hypoxia were detected by CCK8, TUNEL, and Western blot. Flow cytometry was executed to determine the cell cycle. Hypoxia decreased viability and proliferation and increased apoptosis of H9c2 cells, which were ameliorated by PsA pretreatment. The level of miR-24-3p was diminished, but p16 expression was elevated in hypoxia-treated cells and AMI group tissues. MiR-24-3p could sponge p16 in hypoxia-treated cells. Furthermore, the impact of applying miR-24-3p inhibitor on PsA and hypoxia-treated cells could be reversed by si-p16. PsA relieved hypoxia-triggered cell toxicity via miR-24-3p/p16 axis. These findings provided some fresh insights into the potential therapeutic effects of the application of PsA in AMI.


Assuntos
Inibidor p16 de Quinase Dependente de Ciclina/genética , MicroRNAs , Infarto do Miocárdio , Saponinas/farmacologia , Apoptose , Linhagem Celular , Humanos , MicroRNAs/genética , Infarto do Miocárdio/tratamento farmacológico , Miócitos Cardíacos
10.
FEBS Open Bio ; 11(11): 2966-2976, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34407320

RESUMO

Myocardial infarction (MI) is caused by the formation of plaques in the arterial walls, leading to a decrease of blood flow to the heart and myocardium injury as a result of hypoxia. Ferroptosis is a crucial event in myocardial injury, and icariin (ICA) exerts protective effects against myocardial injury. Here, we investigated the protective mechanism of ICA in hypoxia/reoxygenation (H/R)-induced ferroptosis of cardiomyocytes. H9C2 cells were subjected to H/R induction. The content of lactate dehydrogenase and the levels of oxidative stress and intracellular ferrous ion Fe2+ were measured. The levels of ferroptosis markers (ACSL4 and GPX4) were detected. H/R-induced H9C2 cells were cultured with ICA in the presence or absence of ferroptosis inducer (erastin). Znpp (an HO-1 inhibitor) was added to ICA-treated H/R cells to verify the role of the Nrf2/HO-1 pathway. H/R-induced H9C2 cells showed reduced viability, enhanced oxidative stress and lactate dehydrogenase content, increased levels of Fe2+ and ACSL4, and decreased levels of GPX4. ICA inhibited H/R-induced ferroptosis and oxidative stress in cardiomyocytes. Erastin treatment reversed the inhibitory effect of ICA on ferroptosis in H/R cells. The expression of Nrf2 and HO-1 in H/R-induced H9C2 cells was reduced, whereas ICA treatment reversed this trend. Inhibition of the Nrf2/HO-1 pathway reversed the protective effect of ICA on H/R-induced ferroptosis. Collectively, our results suggest that ICA attenuates H/R-induced ferroptosis of cardiomyocytes by activating the Nrf2/HO-1 signaling pathway.


Assuntos
Hipóxia Celular/fisiologia , Flavonoides/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Apoptose/efeitos dos fármacos , Hipóxia Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Ferroptose , Flavonoides/metabolismo , Hipóxia/tratamento farmacológico , Hipóxia/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
11.
Medicine (Baltimore) ; 100(22): e26169, 2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-34087878

RESUMO

BACKGROUND: The study aims to evaluate the effectiveness and safety of bloodletting therapy for herpes zoster. METHODS: The following electronic databases will be searched from PubMed (1966 to March 2020), the Cochrane Central Register of Controlled Trials (update to March 2020), EMBASE (1980 to March 2020), China National Knowledge Infrastructure (1979 to March 2020), Wan Fang Data (1980 to March 2020), Chinese Scientific Journal Database (1989 to March 2020), Chinese Biomedical Database (1978 to March 2020) and traditional Chinese medicine Literature Analysis and Retrieval Database (1949 to March 2020). All randomized controlled trials without any limitation of blinding or publication language about this topic will be included, exclude cohort studies and case reports. Two independent researchers will operate article retrieval, duplication removing, screening, quality evaluation, and data analyses by Review Manager (V.5.3.5). Meta-analyses, subgroup analysis, and/or descriptive analysis will be performed based on the included data conditions. RESULTS: High-quality synthesis and/or descriptive analysis of current evidence will be provided from cure rate, converting to clinical diagnosis rate, and side effects of bloodletting. CONCLUSION: This study will provide the evidence of whether bloodletting is an effective and safe intervention for herpes zoster. PROSPERO REGISTRATION NUMBER: CRD42020171976.


Assuntos
Sangria/métodos , Herpes Zoster/terapia , Medicina Tradicional Chinesa/métodos , Sangria/efeitos adversos , Gerenciamento de Dados , Feminino , Herpes Zoster/virologia , Herpesvirus Humano 3/efeitos dos fármacos , Herpesvirus Humano 3/isolamento & purificação , Humanos , Masculino , Medicina Tradicional Chinesa/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Segurança , Resultado do Tratamento , Metanálise como Assunto
12.
RSC Adv ; 12(2): 1028-1034, 2021 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-35425132

RESUMO

Silver sulfide (Ag2S) is a traditional semiconductor material, however, the photoelectric properties of Ag2S particles under different environments are still lacking. In this paper, we reported the preparation of Ag2S particles and their photoelectric properties under different environments. Results showed that the photoelectric performance of Ag2S particles was closely related to the environment. It was found that a copper phthalocyanine coating could improve the light response, the mixture of alcohols and air could increase the photoconductivity, and the mixture of carbon disulfide and air could decrease the photoconductivity. The mechanism of the effect of various experimental conditions on photoelectric properties was also discussed.

13.
RSC Adv ; 11(54): 34095-34100, 2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-35497268

RESUMO

Although cuprous phosphide (Cu3P) has been widely studied and applied in other fields, its photoluminescence (PL) properties are rarely investigated. Herein, we report that Cu3P can emit near-infrared light at 750 nm. We show that the annealing and the presence of cuprous oxide can enhance the PL emission. The mechanism of the PL enhancement is the improvement of crystal quality and the formation of a space charge region. Our results provide a reference for improving the PL properties of p-type semiconductors.

14.
J Clin Invest ; 130(7): 3621-3636, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32484462

RESUMO

Enteric neuronal degeneration, as seen in inflammatory bowel disease, obesity, and diabetes, can lead to gastrointestinal dysmotility. Pyroptosis is a novel form of programmed cell death but little is known about its role in enteric neuronal degeneration. We observed higher levels of cleaved caspase-1, a marker of pyroptosis, in myenteric ganglia of overweight and obese human subjects compared with normal-weight subjects. Western diet-fed (WD-fed) mice exhibited increased myenteric neuronal pyroptosis, delayed colonic transit, and impaired electric field stimulation-induced colonic relaxation responses. WD increased TLR4 expression and cleaved caspase-1 in myenteric nitrergic neurons. Overactivation of nitrergic neuronal NF-κB signaling resulted in increased pyroptosis and delayed colonic motility. In caspase-11-deficient mice, WD did not induce nitrergic myenteric neuronal pyroptosis and colonic dysmotility. To understand the contributions of saturated fatty acids and bacterial products to the steps leading to enteric neurodegeneration, we performed in vitro experiments using mouse enteric neurons. Palmitate and lipopolysaccharide (LPS) increased nitrergic, but not cholinergic, enteric neuronal pyroptosis. LPS gained entry to the cytosol in the presence of palmitate, activating caspase-11 and gasdermin D, leading to pyroptosis. These results support a role of the caspase-11-mediated pyroptotic pathway in WD-induced myenteric nitrergic neuronal degeneration and colonic dysmotility, providing important therapeutic targets for enteric neuropathy.


Assuntos
Caspases Iniciadoras/metabolismo , Caspases/metabolismo , Colo , Dieta Ocidental/efeitos adversos , Sistema Nervoso Entérico , Motilidade Gastrointestinal , Neurônios , Piroptose , Animais , Caspases/genética , Caspases Iniciadoras/genética , Colo/enzimologia , Colo/inervação , Colo/patologia , Sistema Nervoso Entérico/enzimologia , Sistema Nervoso Entérico/patologia , Feminino , Humanos , Masculino , Camundongos , Camundongos Knockout , Neurônios/enzimologia , Neurônios/patologia
15.
ACS Appl Mater Interfaces ; 12(24): 27572-27577, 2020 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-32453541

RESUMO

Transient conductors are one of the most important components in transient electronics, which attract great attention because of their environment-friendly and biocompatible characters. To meet the requirement for wearable electronics, good stretchability and mechanical durability are needed for the transient conductors. However, it remains challenging to achieve stretchability and transient behavior simultaneously because of a lack of the proper elastomer. Herein, we demonstrate the first highly stretchable and transient conductor from a composite material of Ag flakes and gelatin hydrogel. It shows a maximum stretchability of more than 100% with minimal resistance increase and a good cyclic durability of 1000 cycles of deformation at 20%. The above mentioned good mechanical properties come from the rational design of the conductor with a seamless interface between the hydrogel and Ag flakes. When the conductor is immersed in water at 60 °C, it can be quickly dissolved within 90 s, and the transient behavior can be controlled by tuning the content of the hydrogel in the conductors and dissolving temperature. These properties make the conductor a good wiring candidate for stretchable and transient electronics.

16.
RSC Adv ; 10(55): 33112-33118, 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-35515073

RESUMO

Transient electronics have been widely researched to solve the electronic waste (E-waste) issue. Although various transient materials and devices have been reported, the fabrication technique for transient conductors always uses expensive sputtering or evaporation processes. In this study, a silver flake (AgF) and polyvinyl pyrrolidone (PVP) composite is prepared for conductive and transient tracks. The AgF/PVP composite tracks are highly conductive with a resistivity of 8.9 mOhm cm after sintering at 80 °C for only 3 minutes. Impressively, the AgF/PVP tracks disintegrate in water in 3 minutes due to the fast dissolution of the water-soluble PVP. The transient behavior of the AgF/PVP tracks has potential in transient electronics as demonstrated in a light emitting diode (LED) circuit and antenna.

17.
Spectrochim Acta A Mol Biomol Spectrosc ; 226: 117645, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31622829

RESUMO

A dual-function fluorescent Probe 1 has been synthesized conveniently by coupling rhodamine hydrazone with O-vinyl protected hydroxyl benzaldehyde. Probe 1 was a highly selective and sensitive chemodosimeter for Hg2+ through specific hydrolysis reaction of vinyl ethers with significant fluorescence quenching in CH3CN-PBS buffer (3:7, v/v) solution. Meanwhile, Probe 1 showed a ratiometric fluorescent detection of Cu2+ with a remarkable large Stokes shift (150 nm) by the opening of the spirolactam ring in CH3CN-PBS buffer (3:7, v/v) solution. Hence, the two recognition mechanisms realized well by using a single fluorescent probe. Moreover, Probe 1 could be efficiently applied to the combinatorial logic circuit of NOR and INHIBIT gates through the procured spectral results, respectively.

18.
Nanomaterials (Basel) ; 9(9)2019 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-31540315

RESUMO

Two-dimensional (2D) tungsten disulfide (WS2) has inspired great efforts in optoelectronics, such as in solar cells, light-emitting diodes, and photodetectors. However, chemical vapor deposition (CVD) grown 2D WS2 domains with the coexistence of a discontinuous single layer and multilayers are still not suitable for the fabrication of photodetectors on a large scale. An emerging field in the integration of organic materials with 2D materials offers the advantages of molecular diversity and flexibility to provide an exciting aspect on high-performance device applications. Herein, we fabricated a photodetector based on a 2D-WS2/organic semiconductor materials (mixture of the (Poly-(N, N'-bis-4-butylphenyl-N, N'-bisphenyl) benzidine and Phenyl-C61-butyric acid methyl ester (Poly-TPD/PCBM)) heterojunction. The application of Poly-TPD/PCBM organic blend film enhanced light absorption, electrically connected the isolated WS2 domains, and promoted the separation of electron-hole pairs. The generated exciton could sufficiently diffuse to the interface of the WS2 and the organic blend layers for efficient charge separation, where Poly-TPD was favorable for hole carrier transport and PCBM for electron transport to their respective electrodes. We show that the photodetector exhibited high responsivity, detectivity, and an on/off ratio of 0.1 A/W, 1.1 × 1011 Jones, and 100, respectively. In addition, the photodetector showed a broad spectral response from 500 nm to 750 nm, with a peak external quantum efficiency (EQE) of 8%. Our work offers a facile solution-coating process combined with a CVD technique to prepare an inorganic/organic heterojunction photodetector with high performance on silicon substrate.

19.
Materials (Basel) ; 12(12)2019 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-31212730

RESUMO

Monolayer tungsten disulfide (2D WS2) films have attracted tremendous interest due to their unique electronic and optoelectronic properties. However, the controlled growth of monolayer WS2 is still challenging. In this paper, we report a novel method to grow WS2 through chemical vapor deposition (CVD) with ZnO crystalline whisker as a growth promoter, where partially evaporated WS2 reacts with ZnO to form ZnWO4 by-product. As a result, a depletion region of W atoms and S-rich region is formed which is favorable for subsequent monolayer growth of WS2, selectively positioned on the silicon oxide substrate after the CVD growth.

20.
RSC Adv ; 9(51): 29628-29635, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-35531507

RESUMO

Monolayer tungsten disulfide (WS2) with a direct band gap of ca. 2.0 eV and stable properties has been a hotspot in two-dimensional (2D) nanoelectronics and optoelectronics. However, it remains challenging to successfully prepare monolayer WS2. In this paper, we report the chemical vapor deposition (CVD) growth behavior of hexagonal WS2 monolayers by using WS2 powders and sodium triosulfate (Na2S2O3) as precursors. We observed the Na2S2O3 has a significant effect on the WS2 triangular and leaf-like shapes. In addition, based on proposed S-termination and W-termination theory, the growth mechanisms for different shapes of WS2 were discussed.

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