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1.
Nature ; 607(7919): 480-485, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35859196

RESUMO

Pyroelectricity describes the generation of electricity by temporal temperature change in polar materials1-3. When free-standing pyroelectric materials approach the 2D crystalline limit, how pyroelectricity behaves remained largely unknown. Here, using three model pyroelectric materials whose bonding characters along the out-of-plane direction vary from van der Waals (In2Se3), quasi-van der Waals (CsBiNb2O7) to ionic/covalent (ZnO), we experimentally show the dimensionality effect on pyroelectricity and the relation between lattice dynamics and pyroelectricity. We find that, for all three materials, when the thickness of free-standing sheets becomes small, their pyroelectric coefficients increase rapidly. We show that the material with chemical bonds along the out-of-plane direction exhibits the greatest dimensionality effect. Experimental observations evidence the possible influence of changed phonon dynamics in crystals with reduced thickness on their pyroelectricity. Our findings should stimulate fundamental study on pyroelectricity in ultra-thin materials and inspire technological development for potential pyroelectric applications in thermal imaging and energy harvesting.

2.
Plant Dis ; 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38698518

RESUMO

Tree peony black spot (TPBS), mainly caused by Alternaria suffruticosae, is a common leaf disease on the ornamental peony, which posed a great threat on the flower buds in the current year and the flowering quality in the next year. However, there was only one fungicide registered for the control of the disease, difenoconazole. In order to avoid the severe problem of pathogen resistance caused by long-term use of difenoconazole, it is necessary to screen more chemical fungicides for the prevention and control of TPBS. In the paper, the biological activities of flutolanil, phenamacril, pyraclostrobin, and boscalid on mycelial growth, conidial germination, germ tube elongation and sporulation quantity of A. suffruticosae were determined, and field control efficacy were conducted to evaluate the preventive and therapeutic activities. Difenoconazole, was used as a control simultaneously. The results showed that pyraclostrobin had the strongest inhibitory effects on the conidial germination, mycelium growth, germ tube elongation and sporulation quantity, with the average EC50 of 0.0517, 0.5343, 0.0008 and 0.8068 µg/mL respectively. The inhibitory activity of flutolanil on the four developmental stages of A. suffruticosae was weaker than the other three fungicides. Compared with flutolanil, boscalid, the other succinate dehydrogenase inhibitors, had more srtong inhibitory effects on the mycelial growth and sporulation quantity, with the average EC50 of 3.8603 and 1.4760 µg/mL respectively. Phenamacril had a moderate inhibitory level, which had more inhibitory activity on conidial germination and germ tube elongation, with the average EC50 of 31.5349 and 5.2597 µg/mL. All of the four fungicides had no significant effects on the shape of spores and germ tubes. The control fungicide difenoconazole had the strongest inhibitory activity on mycelial growth, and the average EC50 was only 0.3297 µg/ml. However, its inhibitory activity on the other three growth stages was not high. In the field trials, pyraclostrobin had high control efficacy on TPBS even at low concentrations, reaching a minimum of 62.6293%, which was higher than that of difenoconazole. The other three fungicides had higher control efficacy at high concentrations, but decreased significantly at low concentrations. Considering the dosage and control efficacy, pyraclostrobin was the first choice for the control of TPBS. Pyraclostrobin is the preferred alternative fungicide of difenoconazole for the prevention and control of TPBS in production.

3.
Nanotechnology ; 34(40)2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37406614

RESUMO

Photocatalytic CO2reduction is considered to be an appealing way of alleviating environmental pollution and energy shortages simultaneously under mild condition. However, the activity is greatly limited by the poor separation of the photogenerated carriers. Ion doping is a feasible strategy to facilitate the charge transfer. In this work, Ni-doped Bi4O5I2photocatalyst is successfully fabricated using a one-pot hydrothermal method. A few doping levels appear in the energy band of Bi4O5I2after Ni doping, which are used as springboards for electrons transition, thus promoting photoexcited electrons and holes separation. As a consequence, a remarkably enhanced yield of CO and CH4(6.2 and 1.9µmol g-1h-1) is obtained over the optimized Bi4O5I2-Ni15, which is approximately 2.1 and 3.8 times superior to pure Bi4O5I2, respectively. This work may serve as a model for the subsequent research of Bi-based photocatalysts to implement high-performance CO2photoreduction.

4.
Plant Dis ; 107(12): 3843-3850, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37272042

RESUMO

Fusarium pseudograminearum is the dominant pathogen causing Fusarium crown rot (FCR) of wheat. Phenamacril is a 2-cyanoacrylate fungicide, having a control effect on diseases caused by Fusarium spp. The objective of this study was to investigate the inhibitory effect of phenamacril on F. pseudograminearum and its control efficacy against FCR. The results showed that phenamacril had a strong inhibitory effect on the mycelial growth of F. pseudograminearum, EC50 values of phenamacril to 63 tested strains were in the range of 0.0998 to 0.5672 µg/ml, and the average EC50 value was 0.3403 ± 0.0872 µg/ml and could be used as the baseline sensitivity of F. pseudograminearum to phenamacril. Phenamacril reduced the germination rate of conidia of F. pseudograminearum, and the EC50 value was 5.0273 to 26.4814 µg/ml. In addition, we found that phenamacril had a teratogenic effect on conidia and blastotubules, which increased the ratio of conidial germination from the middle cells and showed high efficacy on the sporulation quantity of F. pseudograminearum with an EC50 value in the range of 0.0770 to 0.1064 µg/ml. There was no significant correlation between the sensitivity of F. pseudograminearum to phenamacril and its sensitivity to fludioxonil, carbendazim, tebuconazole, and kresoxim-methyl. In vitro and greenhouse assays showed that the treatment with 0.125 µl of active ingredient per gram recorded the best control effect on wheat crown rot, reaching 87.8 and 77.3%, respectively. In two experimental sites in Luoyang, phenamacril also had great control effect against FCR, reaching 83.9%. It was proven that phenamacril has a superior control effect against FCR. This study has laid a foundation for the study of the mechanism of action of phenamacril against F. pseudograminearum and provided a theoretical basis for the application of phenamacril to control FCR.


Assuntos
Fusarium , Triticum , Doenças das Plantas/prevenção & controle , Cianoacrilatos/farmacologia , Crescimento e Desenvolvimento
5.
BMC Anesthesiol ; 22(1): 267, 2022 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-35996073

RESUMO

BACKGROUND: Postoperative delirium (POD) is a critical complication in patients accepting colon carcinoma surgery. Neostigmine, as a cholinesterase inhibitor, can enhance the transmission of cholinergic transmitters in synaptic space, and play an important role in maintaining the normal level of cognition, attention and consciousness. The objective of this study was to investigate the effect of neostigmine on POD and clinical prognosis. METHODS: A randomized, double-blind controlled trial was implemented in Qingdao Municipal Hospital Affiliated to Qingdao University. A total of 454 patients aged 40 to 90 years old accepted colon carcinoma surgery were enrolled between June 7, 2020, and June 7, 2021, with final follow-up on December 8, 2021. Patients were randomly assigned to two groups: the neostigmine group (group N) and the placebo group (group P), the patients in group N were injected with 0.04 mg/kg neostigmine and 0.02 mg/kg atropine intravenously. The primary endpoint was the incidence of POD, researchers evaluated the occurrence of POD by the Confusion Assessment Method (CAM) twice daily (at 10 a.m. and 2 p.m.) during the first 7 postoperative days, POD severity was assessed by the Memorial Delirium Assessment Scale (MDAS). The secondary endpoints were the extubating time, postanesthesia care unit (PACU) time, the incidence of various postoperative complications, length of hospital stays, and 6 months postoperative mortality. RESULTS: The incidence of POD was 20.20% (81/401), including 19.39% (38/196) in group N and 20.98% (43/205) in group P. There was no significant statistical significance in the incidence of POD between group N and group P (P > 0.05); Compared to group P, the extubating time and PACU time in group N were significantly reduced (P < 0.001), the incidence of postoperative pulmonary complications (POPCs) decreased significantly in group N (P < 0.05), while no significant differences were observed in postoperative hospital stay and mortality in 6 months between the two groups (P > 0.05). CONCLUSION: For patients accepted colon carcinoma surgery, neostigmine did not significantly reduce the incidence of POD, postoperative mortality and postoperative hospital stay, while it indeed reduced the extubating time, PACU time and the incidence of POPCs. TRIAL REGISTRATION: The randomized, double-blind, controlled trial was registered retrospectively at www.chictr.org.cn on 07/06/2020 (ChiCTR2000033639).


Assuntos
Carcinoma , Delírio , Adulto , Idoso , Idoso de 80 Anos ou mais , Colo , Delírio/epidemiologia , Delírio/etiologia , Delírio/prevenção & controle , Método Duplo-Cego , Humanos , Pessoa de Meia-Idade , Neostigmina/uso terapêutico , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Estudos Retrospectivos
6.
BMC Med Educ ; 22(1): 263, 2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35410238

RESUMO

BACKGROUND: Radial artery cannulation is a crucial investigative procedure for measuring patients' blood pressure invasively and serial blood gases. However, radial artery cannulation can be challenging for medical residents, and it is necessary to establish a facile and straightforward teaching strategy. This study aimed to evaluate the efficiency of acoustic shadowing-facilitated ultrasound guidance on radial artery cannulation teaching for medical residents. METHODS: A total of 116 medical postgraduates who underwent standardized residency training programs in the Department of Anesthesiology were randomly divided into a new ultrasound-guided teaching group and a traditional ultrasound-guided teaching group. In the new ultrasound-guided teaching group, radial artery puncture technique was taught by acoustic shadowing-facilitated ultrasound guidance. The training included both theoretical and practical components. After the training, the success rate of the first puncture attempt, the success rate of the catheterization, the ultrasonic positioning time, and the catheterization time of the two groups were compared in a unified manner. A questionnaire on the subjective evaluation of the various aspects of the program by participants was conducted at the end of the training period. RESULTS: The study included 101 medical residents. The success rate for radial artery puncture at the first attempt in the new ultrasound-guided teaching group was 78.43%. It was significantly higher than that of the traditional ultrasound-guided group (58.00%, odds ratio = 0.380; 95% CI = 0.159 to 0.908; p = 0.027). The success rate for the first arterial catheterization in the new ultrasound-guided teaching group was significantly higher than that of the traditional ultrasound-guided group (74.51% vs. 52.00%, odds ratio = 0.371; 95% CI = 0.160 to 0.858; p = 0.019). The ultrasonic positioning time and catheterization time in minutes in the new ultrasound-guided teaching group were significantly shorter than that of the traditional ultrasound-guided group (14.36 ± 3.31 vs. 18.02 ± 4.95, p < 0.001; 10.43 ± 2.38 vs. 14.78 ± 8.02, p = 0.012). However, no significant differences were observed in the incidence of local hematomas and teaching satisfaction scores between the two groups. CONCLUSION: Acoustic shadowing facilitates ultrasound-guided radial artery puncture and catheterization is beneficial in the standardized training and teaching of residents. It improves the success rate of the first attempt at radial artery puncture and catheterization and shortens the time of ultrasound location and catheterization. TRIAL REGISTRATION: Registered in the Chinese Clinical Trial Registry on 28 May 2021. REGISTRATION NUMBER: ChiCTR2100046833 .


Assuntos
Cateterismo Periférico , Artéria Radial , Acústica , Cateterismo Periférico/métodos , Humanos , Punções/métodos , Artéria Radial/diagnóstico por imagem , Ultrassonografia de Intervenção/métodos
7.
Nano Lett ; 20(1): 33-42, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31769995

RESUMO

The reconfigurability of the electrical heterostructure featured with external variables, such as temperature, voltage, and strain, enabled electronic/optical phase transition in functional layers has great potential for future photonics, computing, and adaptive circuits. VO2 has been regarded as an archetypal phase transition building block with superior metal-insulator transition characteristics. However, the reconfigurable VO2-based heterostructure and the associated devices are rare due to the fundamental challenge in integrating high-quality VO2 in technologically important substrates. In this report, for the first time, we show the remote epitaxy of VO2 and the demonstration of a vertical diode device in a graphene/epitaxial VO2/single-crystalline BN/graphite structure with VO2 as a reconfigurable phase-change material and hexagonal boron nitride (h-BN) as an insulating layer. By diffraction and electrical transport studies, we show that the remote epitaxial VO2 films exhibit higher structural and electrical quality than direct epitaxial ones. By high-resolution transmission electron microscopy and Cs-corrected scanning transmission electron microscopy, we show that a graphene buffered substrate leads to a less strained VO2 film than the bare substrate. In the reconfigurable diode, we find that the Fermi level change and spectral weight shift along with the metal-insulator transition of VO2 could modify the transport characteristics. The work suggests the feasibility of developing a single-crystalline VO2-based reconfigurable heterostructure with arbitrary substrates and sheds light on designing novel adaptive photonics and electrical devices and circuits.

8.
Int J Mol Sci ; 21(2)2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31941102

RESUMO

Previous studies have suggested that immune system development and weaning stress are closely related to the maturation of gut microbiota. The early-life period is a "window of opportunity" for microbial colonization, which potentially has a critical impact on the development of the immune system. Fecal microbiota transplantation (FMT) and probiotics are often used to regulate gut microbial colonization. This study aims to test whether early intervention with FMT using fecal microbiota from gestation sows combined with Clostridium butyricum and Saccharomyces boulardii (FMT-CS) administration could promote the maturation of gut microbiota and development of immune system in piglets. Piglets were assigned to control (n = 84) and FMT-CS treatment (n = 106), which were treated with placebo and bacterial suspension during the first three days after birth, respectively. By 16S rRNA gene sequencing, we found that FMT-CS increased the α-diversity and reduced the unweighted UniFrac distances of the OTU community. Besides, FMT-CS increased the relative abundance of beneficial bacteria, while decreasing that of opportunistic pathogens. FMT-CS also enhanced the relative abundance of genes related to cofactors and vitamin, energy, and amino acid metabolisms during the early-life period. ELISA analysis revealed that FMT-CS gave rise to the plasma concentrations of IL-23, IL-17, and IL-22, as well as the plasma levels of anti-M.hyo and anti-PCV2 antibodies. Furthermore, the FMT-CS-treated piglets showed decreases in inflammation levels and oxidative stress injury, and improvement of intestinal barrier function after weaning as well. Taken together, our results suggest that early-life intervention with FMT-CS could promote the development of innate and adaptive immune system and vaccine efficacy, and subsequently alleviate weaning stress through promoting the maturation of gut microbiota in piglets.


Assuntos
Clostridium butyricum/imunologia , Transplante de Microbiota Fecal , Microbioma Gastrointestinal/imunologia , Probióticos/farmacologia , Saccharomyces boulardii/imunologia , Estresse Fisiológico , Animais , Animais Recém-Nascidos , Citocinas/imunologia , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/imunologia , Suínos , Desmame
9.
J Gastroenterol Hepatol ; 34(1): 284-292, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30144357

RESUMO

BACKGROUND AND AIM: ß-Arrestins (ß-arrs) are regulators and mediators of G protein-coupled receptor signaling that are functionally involved in inflammation. Nuclear factor-κB p65 (NF-κBp65) activation has been observed early in the onset of pancreatitis. However, the effect of ß-arrs in acute pancreatitis (AP) is unclear. The aim of this study is to investigate whether ß-arrs are involved in AP through activation of NF-κBp65. METHODS: Acute pancreatitis was induced by either caerulein injection or choline-deficient supplemented with ethionine diet (CDE). ß-arr1 wild-type and ß-arr1 knockout mice were used in the experiment. The survival rate was calculated in the CDE model mice. Histological and western blot analyses were performed in the caerulein model. Inflammatory mediators were detected by real-time polymerase chain reaction in the caerulein-induced AP mice. Furthermore, AR42J and PANC-1 cell lines were used to further study the effects of ß-arr1 in caerulein-induced pancreatic cells. RESULTS: ß-Arr1 but not ß-arr2 is significantly downregulated in caerulein-induced AP in mice. Targeted deletion of ß-arr1 notably upregulated expression of the pancreatic inflammatory mediators including tumor necrosis factor α and interleukin 1ß as well as interleukin 6 and aggravated AP in caerulein-induced mice. ß-Arr1 deficiency increased mortality in mice with CDE-induced AP. Further, ß-arr1 deficiency enhanced caerulein-induced phosphorylation of NF-κBp65 both in vivo and in vitro. CONCLUSION: ß-Arr1 alleviates AP via repression of NF-κBp65 activation, and it is a potentially therapeutic target for AP.


Assuntos
Pancreatite/genética , Pancreatite/metabolismo , Fator de Transcrição RelA/antagonistas & inibidores , Fator de Transcrição RelA/metabolismo , beta-Arrestina 1/genética , beta-Arrestina 1/metabolismo , Doença Aguda , Animais , Linhagem Celular Tumoral , Ceruletídeo , Deficiência de Colina/complicações , Modelos Animais de Doenças , Regulação para Baixo , Etionina , Feminino , Humanos , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Camundongos Knockout , Pancreatite/induzido quimicamente , Pancreatite/patologia , Fosforilação , Taxa de Sobrevida , Fator de Necrose Tumoral alfa/metabolismo
10.
Phys Chem Chem Phys ; 20(17): 12272-12277, 2018 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-29687804

RESUMO

The evaporation of nanoscale water films on surfaces affects many processes in nature and industry. Using molecular dynamics (MD) simulations, we show the evaporation of a nanoscale water film on a uniformly complete wetting surface at different temperatures. With the increase in temperature, the growth of the water evaporation rate becomes slow. Analyses show that the hydrogen bond (H-bond) lifetimes and orientational autocorrelation times of the outermost water film decrease slowly with the increase in temperature. Compared to a thicker water film, the H-bond lifetimes and orientational autocorrelation times of a monolayer water film are much slower. This suggests that the lower evaporation rate of the monolayer water film on a uniformly complete wetting surface may be caused by the constriction of the water rotation due to the substrate. This finding may be helpful for controlling nanoscale water evaporation within a certain range of temperatures.

11.
Nano Lett ; 16(12): 7974-7981, 2016 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-27960450

RESUMO

One-dimensional nanoscale epitaxial arrays serve as a great model in studying fundamental physics and for emerging applications. With an increasing focus laid on the Cs-based inorganic halide perovskite out of its outstanding material stability, we have applied vapor phase epitaxy to grow well aligned horizontal CsPbX3 (X: Cl, Br, or I or their mixed) nanowire arrays in large scale on mica substrate. The as-grown nanowire features a triangular prism morphology with typical length ranging from a few tens of micrometers to a few millimeters. Structural analysis reveals that the wire arrays follow the symmetry of mica substrate through incommensurate epitaxy, paving a way for a universally applicable method to grow a broad family of halide perovskite materials. The unique photon transport in the one-dimensional structure has been studied in the all-inorganic Cs-based perovskite wires via temperature dependent and spatially resolved photoluminescence. Epitaxy of well oriented wire arrays in halide perovskite would be a promising direction for enabling the circuit-level applications of halide perovskite in high-performance electro-optics and optoelectronics.

12.
Pathol Res Pract ; 254: 155074, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38246036

RESUMO

OBJECTIVE: The purpose of this study was to thoroughly assess the relevance of circular RNAs (circRNAs) in the diagnosis and prognosis of esophageal squamous cell carcinoma (ESCC), and design a systematic review and meta-analysis. METHODS: Using Stata 14.0 software, a meta-analysis was carried out by looking for pertinent studies up to February 20, 2023, in the online databases PubMed, Embase, Web of Science, and CNKI. The clinicopathologic and prognostic data were evaluated using the combined advantage ratio (OR) and combined hazard ratio (HR), respectively. The threshold effects and publication bias were quantified using Spearman's correlation and the Deeks funnel plot asymmetry tests, respectively. RESULTS: A total of 36 pertinent studies with a literature quality score of 7 or above were included in this study. Of them, 22 papers dealt with clinicopathological characterization, 15 dealt with prognostic analysis, and 13 dealt with diagnostic analysis. The findings demonstrated that high expression of upregulated circRNAs was associated with worse clinicopathological features (tumor size: OR=3.61, 95% CI:1.45-5.78; TNM stage: OR=2.12, 95% CI:1.41-2.83; lymph node metastasis: OR=2.87, 95% CI:1.67-4.07) and worse OS (HR=1.49, 95% CI:1.26-1.77). High downregulated circRNAs expression was linked to improved clinicopathologic characteristics (TNM staging: OR=0.35, 95% CI:0.13- 0.95) and longer survival (HR=0.48, 95% CI:0.27-0.84); combined sensitivity was 0.77 (95% CI: 0.71-0.82), specificity was 0.80 (95% CI:0.74-0.86), and area under the subject operating characteristic curve (AUC) was 0.86 (95% CI:0.82- 0.88). CONCLUSION: CircRNAs are useful for ESCC patient diagnosis and prognosis, and they are anticipated to be unique potential biomarkers for ESCC clinical diagnosis.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Carcinoma de Células Escamosas do Esôfago/diagnóstico , RNA Circular , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/genética , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/genética , Prognóstico , Biomarcadores Tumorais/genética , Células Epiteliais/patologia
13.
Heliyon ; 10(4): e26333, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38420376

RESUMO

Against the backdrop of the gradual advancement of China's electricity market reform, the number of Power Trading Companies in China has been increasing year by year, and as of October 2022, the number has reached more than 10,000. As an important hub connecting the electricity market and users, electricity retailers face double risks from downstream user load fluctuations and electricity market price fluctuations. Therefore, a reasonable power purchase and sale strategy is very important for an electricity retailer. In this study, a block bidding mechanism is adopted to optimize the clearing of the medium-to long-term market and a DA-RBF neural network is established for spot electricity price forecasting model based on numerical feature similarity to improve the accuracy of electricity price forecasting. Furthermore, the model considers the differences in user demand responses and investigates the optimal power purchase and sale strategy, guided by differentiated time-of-use electricity pricing. The case study analysis demonstrated that the proposed power purchase and sale optimization strategy yields favorable results, improving profitability and enhancing the stability of the power system.

14.
ACS Omega ; 9(18): 20185-20195, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38737014

RESUMO

The absolute structures of a pair of infinite Na(H2O)4+-connected ε-Keggin-Al13 species (Na-ε-K-Al13) that were inversion structures and mirror images of each other were determined. Single crystals obtained by adding A2SO4 (A = Li, Na, K, Rb, or Cs) solution to NaOH-hydrolyzed AlCl3 solution were subjected to X-ray structure analyses. The statistical results for 36 single crystals showed that all the crystals had almost the same unit cell parameter, belonged to the same F4̅3m space group, and possessed the same structural formula [Na(H2O)4AlO4Al12(OH)24(H2O)12](SO4)4·10H2O. However, the crystals had two inverse absolute structures (denoted A and B), which had a crystallization ratio of 1:1. From Li+ to Cs+, with increasing volume of the cation coexisting in the mother solution, the degree of disorder of the four H2O molecules in the Na(H2O)4+ hydrated ion continuously decreased; they became ordered when the cation was Cs+. Absolute structures A and B are the first two infinite aluminum polycations connected by statistically occupied [(Na1/4)4(H2O)4]+ hydrated ions. The three-dimensional structure of the infinite Na-ε-K-Al13 species can be regarded as the assembly of finite ε-K-Al13 species linked by [(Na1/4)4(H2O)4]+ in a 1:1 ratio. In this assembly, each [(Na1/4)4(H2O)4]+ is connected to four ε-K-Al13 and each ε-K-Al13 is also connected to four [(Na1/4)4(H2O)4]+ in tetrahedral orientations to form a continuous rigid framework structure, which has an inverse spatial orientation between absolute structure A and B. This discovery clarifies that the ε-K-Al13 (or ε-K-GaAl12) species in Na[MO4Al12(OH)24(H2O)12](XO4)4·nH2O (M = Al, Ga; X = S, Se; n = 10-20) exists as discrete groups and deepens understanding of the formation and evolution process of polyaluminum species in forcibly hydrolyzed aluminum salt solution. The reason why Na+ statistically occupies the four sites was examined, and a formation and evolution mechanism of the infinite Na-ε-K-Al13 species was proposed.

15.
Brief Funct Genomics ; 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37738503

RESUMO

Circular RNAs (circRNAs) are a class of noncoding RNA molecules featuring a closed circular structure. They have been proved to play a significant role in the reduction of many diseases. Besides, many researches in clinical diagnosis and treatment of disease have revealed that circRNA can be considered as a potential biomarker. Therefore, understanding the association of circRNA and diseases can help to forecast some disorders of life activities. However, traditional biological experimental methods are time-consuming. The most common method for circRNA-disease association prediction on the basis of machine learning can avoid this, which relies on diverse data. Nevertheless, topological information of circRNA and disease usually is not involved in these methods. Moreover, circRNAs can be associated with diseases through miRNAs. With these considerations, we proposed a novel method, named THGNCDA, to predict the association between circRNAs and diseases. Specifically, for a certain pair of circRNA and disease, we employ a graph neural network with attention to learn the importance of its each neighbor. In addition, we use a multilayer convolutional neural network to explore the relationship of a circRNA-disease pair based on their attributes. When calculating embeddings, we introduce the information of miRNAs. The results of experiments show that THGNCDA outperformed the SOTA methods. In addition, it can be observed that our method gives a better recall rate. To confirm the significance of attention, we conducted extensive ablation studies. Case studies on Urinary Bladder and Prostatic Neoplasms further show THGNCDA's ability in discovering known relationships between circRNA candidates and diseases.

16.
J Colloid Interface Sci ; 652(Pt B): 1545-1553, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37660611

RESUMO

The development of bifunctional photocatalysts for enhancing hydrogen (H2) and hydrogen peroxide (H2O2) production from water is essential in addressing environmental and energy issues. However, the practical implementation of photocatalytic technology is still constrained by the inadequate separation of photo-generated charge carriers. Herein, potassium (K) atoms are introduced into the interlayers of graphitic carbon nitride (g-C3N4) with a hollow hexagonal structure (K-TCN) and are coordinated with N atoms in adjacent layers. The presence of K-N coordination serves as a layer bridge, facilitating the separation of charge carriers. The hollow hexagonal structure reduces the distance over which photogenerated electrons migrate to the surface, thereby enhancing the reaction kinetics. Consequently, the optimized K-TCN exhibits a dramatically improved photocatalytic H2 (941.6 µmol g-1h-1 with platinum (Pt) as the cocatalyst) and H2O2 (347.6 µmol g-1h-1) generation as compared to hollow g-C3N4 (TCN) and bulk g-C3N4 nanosheet (CN) without K-N bridge under visible light irradiation. The unique design holds promising potential for developing highly efficient bifunctional photocatalysts towards producing renewable fuels and value-added chemicals.

17.
ACS Nano ; 17(12): 11783-11793, 2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37306683

RESUMO

Strongly correlated electron materials harbor interesting materials physics, such as high-Tc superconductivity, colossal magnetoresistance, and metal-insulator transition. These physical properties can be greatly influenced by the dimensionality and geometry of the hosting materials and their interaction strengths with underlying substrates. In a classic strongly correlated oxide vanadium sesquioxide (V2O3), the coexistence of a metal-insulator and paramagnetic-antiferromagnetic transitions at ∼150 K makes this material an excellent platform for exploring basic physics and developing future devices. So far, most studies have been focused on epitaxial thin films in which the strongly coupled substrate has a pronounced effect on V2O3, leading to the observations of intriguing phenomena and physics. In this work, we unveil the kinetics of a metal-insulator transition of V2O3 single-crystal sheets at nano and micro scales. We show the presence of triangle-like alternating metal/insulator phase patterns during phase transition, which is drastically different from the epitaxial film. The observation of single-stage metal-insulator transition in V2O3/graphene compared to the multistage in V2O3/SiO2 evidence the importance of sheet-substrate coupling. Harnessing the freestanding form of the V2O3 sheet, we show that the phase transition of V2O3 sheet can generate a large dynamic strain to monolayer MoS2 and tune its optical property based on the MoS2/V2O3 hybrid structure. The demonstration of the capability in tuning phase transition kinetics and phase patterns using designed hybrid structure of varied sheet-substrate coupling strengths suggests an effective knob in the design and operation of emerging Mott devices.

18.
Adv Mater ; 34(19): e2108102, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34847262

RESUMO

In recent years, perovskite light-emitting diodes (PeLEDs) have emerged as a promising new lighting technology with high external quantum efficiency, color purity, and wavelength tunability, as well as, low-temperature processability. However, the operational stability of PeLEDs is still insufficient for their commercialization. The generation and migration of ionic species in metal halide perovskites has been widely acknowledged as the primary factor causing the performance degradation of PeLEDs. Herein, this topic is systematically discussed by considering the fundamental and engineering aspects of ion-related issues in PeLEDs, including the material and processing origins of ion generation, the mechanisms driving ion migration, characterization approaches for probing ion distributions, the effects of ion migration on device performance and stability, and strategies for ion management in PeLEDs. Finally, perspectives on remaining challenges and future opportunities are highlighted.

19.
Front Neurosci ; 16: 935869, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36353596

RESUMO

Objective: Postoperative delirium (POD) is a common postoperative complication, which may be associated with α-synuclein (α-syn). The purpose of this study was to explore the association between the expression level of α-syn in cerebrospinal fluid (CSF) and POD. Methods: We conducted a prospective observational cohort study, which involved in 740 participants (mean age of 61.86 years, range 40-90 years; 40% female) from the Perioperative Neurocognitive Disorder And Biomarker Lifestyle (PNDABLE) study in the final analysis. POD was diagnosed using the Confusion Assessment Scale (CAM), and its severity was measured using the Memorial Delirium Assessment Scale (MDAS). Enzyme-linked immune-sorbent assay (ELISA) was used to detect the concentrations of α-syn, Aß40, Aß42, T-tau, and P-tau in CSF. Results: The incidence of POD was 11.22% (83/740). The logistic regression analysis showed that the increased concentrations of CSF α-syn (OR = 1.005, 95%CI 1.004-1.006, P < 0.001), P-tau (OR = 1.093, 95%CI 1.071-1.115, P < 0.001), and T-tau (OR = 1.008, 95%CI 1.006-1.009, P < 0.001) were risk factors of POD. Linear regression showed that CSF α-syn had positive correlations with P-tau (ß = 0.480, P < 0.001), T-tau (ß = 0.334, P < 0.001), while negative correlations with Aß40 (ß = -0.378 P < 0.001), Aß42 (ß = -0.800, P = 0.001) in POD patients. Mediation analyses showed the association between α-syn and POD was partially mediated by tau pathologies (proportion: 16-17%). Conclusion: CSF α-syn is one of the preoperative risk factors for POD, which may be mediated through tau pathologies. Clinical trial registration: [www.ClinicalTrials.gov], identifier [ChiCTR20 00033439].

20.
Cell Mol Bioeng ; 15(1): 151-160, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35096190

RESUMO

INTRODUCTION: Periodontal healing requires an adequate number of periodontal ligament (PDL) cells to rebuild the impaired tissue. Phenytoin (PHT) has been reported to promote wound healing and extracellular matrix deposition, which indicates its promising application of periodontal healing. However, the effects of PHT on PDL cells behavior and the underlying mechanism are still unknown. METHODS: Human PDL cells were cultured and identified. 20-100 µg/mL PHT were used in our study. The proliferation of PDL cells was determined by the EdU assay. A wound healing assay was used to detect cell migration. Matrix metalloproteinase (MMP)-1, MMP-2, tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2 expression were analyzed by real time-PCR. The protein expression of MMP-1 and phosphorylated mitogen-activated protein kinases (MAPKs) were detected by western blotting assay. Osteogenic differentiation was assessed by alkaline phosphatase (ALP) staining. RESULTS: We found that 20-100 µg/mL of PHT did not affect PDL cells proliferation, whereas 50-100 µg/mL of PHT inhibited cell migration. The 50 or 100 µg/mL of PHT decreased the gene and protein expression of MMP-1, but increased the gene expression of TIMP-1. MMP-2 and TIMP-2 were not affected by 20-100 µg/mL of PHT. Further, 20-50 µg/mL of PHT increased ALP expression, but 100 µg/mL of PHT depressed ALP expression. The extracellular regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38 were activated by PHT. JNK and ERK are involved in PHT-regulated migration. JNK plays an essential role in PHT-induced osteogenic differentiation. CONCLUSIONS: MAPK pathway involved in PHT-regulated migration and osteogenic differentiation in human PDL cells.

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