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1.
iScience ; 27(5): 109621, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38638568

RESUMO

Light olefins are key intermediates in the synthesis of petrochemicals, and the conversion of stabilized carbon dioxide to light olefins using catalysts containing halogenated elements such as chlorine is a major challenge. Building on previous reports emphasizing the toxic effects of halogen elements on catalysts, we present the synthesis of FeMnKBr/YNa catalysts. This involved the synthesis of the catalyst by melt permeation using Br-containing potassium salts, other metal nitrates and YNa zeolites. The catalyst performed well in converting syngas (H2/CO2 = 3) to light olefins with a selectivity of 56.2%, CO2 conversion of 34.4%, and CO selectivity of 13.6%. Adding Br aids in reducing the Fe phase, boosts catalyst carburization, and produces more iron carbide species. It also moderately deposits carbon on the active center's surface, enhancing active phase dispersion. Br's electronegativity mitigates the influence of K, reducing catalyst's carbon-carbon coupling ability, leading to more low-carbon olefins generation.

2.
Nanotechnology ; 35(27)2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38522106

RESUMO

Light and thermal detectors based on the laser-induced transverse voltage (LITV) effect have garnered significant interest for their rapid and broad spectral response. In this study, we prepared the La-doped SrTiO3(STO) epitaxial thin films on the 12° inclined single crystal LaAlO3(LAO) (100) substrates using our home-designed metal-organic chemical vapor deposition system. Under the illumination of a 248 nm laser, the LITV signals of LaxSr1-xTiO3films were observed and showed dependence on the La doping level, which can be explained by the changes in the light absorption coefficient, thermal conductivity, and optical penetration depth. The optimized LITV signal was observed with a peak voltage of 23.25 V and a decay time of 106 ns under the laser power density of 1.0 mJ mm-2. The high peak voltage and fast response time of LaxSr1-xTiO3show great potential in the field of light and thermal detection.

3.
Nanotechnology ; 35(15)2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38176072

RESUMO

Semiconductor photocatalysis holds significant promise in addressing both environmental and energy challenges. However, a major hurdle in photocatalytic processes remains the efficient separation of photoinduced charge carriers. In this study, TiO2nanorod arrays were employed by glancing angle deposition technique, onto which Ti3C2TxMXene was deposited through a spin-coating process. This hybrid approach aims to amplify the photocatalytic efficacy of TiO2nanorod arrays. Through photocurrent efficiency characterization testing, an optimal loading of TiO2/Ti3C2Txcomposites is identified. Remarkably, this composite exhibits a 40% increase in photocurrent density in comparison to pristine TiO2. This enhancement is attributed to the exceptional electrical conductivity and expansive specific surface area inherent to Ti3C2TxMXene. These attributes facilitate swift transport of photoinduced electrons, consequently refining the separation and migration of electron-hole pairs. The synergistic TiO2/Ti3C2Txcomposite showcases its potential across various domains including photoelectrochemical water splitting and diverse photocatalytic devices. As such, this composite material stands as a novel and promising entity for advancing photocatalytic applications. This study can offer an innovative approach for designing simple and efficient photocatalytic materials composed of MXene co-catalysts and TiO2for efficient water electrolysis on semiconductors.

4.
Zhongguo Gu Shang ; 37(1): 15-20, 2024 Jan 25.
Artigo em Chinês | MEDLINE | ID: mdl-38286446

RESUMO

OBJECTIVE: To investigate the effect of bone cement containing recombinant human basic fibroblast growth factor (rhbFGF) and recombinant human bone morphogenetic protein-2 (rhBMP-2) in percutaneous kyphoplasty(PKP)treatment of osteoporotic vertebral compression fracture(OVCF). METHODS: A total of 103 OVCF patients who underwent PKP from January 2018 to January 2021 were retrospectively analyzed, including 40 males and 63 females, aged from 61 to 78 years old with an average of (65.72±3.29) years old. The injury mechanism included slipping 33 patients, falling 42 patients, and lifting injury 28 patients. The patients were divided into three groups according to the filling of bone cement. Calcium phosphate consisted of 34 patients, aged(65.1±3.3) years old, 14 males and 20 females, who were filled with calcium phosphate bone cement. rhBMP-2 consisted of 34 patients, aged (64.8±3.2) years old, 12 males and 22 females, who were filled with bone cement containing rhBMP-2. And rhbFGF+rhBMP-2 consisted of 35 patients, aged (65.1±3.6) years old, 14 males and 21 females, who were filled with bone cement containing rhbFGF and rhBMP-2. Oswestry disability index (ODI), bone mineral density, anterior edge loss height, anterior edge compression rate of injured vertebra, visual analog scale (VAS) of pain, and the incidence of refracture were compared between groups. RESULTS: All patients were followed for 12 months. Postoperative ODI and VAS score of the three groups decreased (P<0.001), while bone mineral density increased (P<0.001), anterior edge loss height, anterior edge compression rate of injured vertebra decreased first and then slowly increased (P<0.001). ODI and VAS of group calcium phosphate after 1 months, 6 months, 12 months were lower than that of rhBMP-2 and group rhbFGF+rhBMP-2(P<0.05), bone mineral density after 6 months, 12 months was higher than that of rhBMP-2 and group calcium phosphate(P<0.05), and anterior edge loss height, anterior edge compression rate of injured vertebra of group rhbFGF+rhBMP-2 after 6 months and 12 months were lower than that of group rhBMP-2 and group calcium phosphate(P<0.05). There was no statistical difference in the incidence of re-fracture among the three groups (P>0.05). CONCLUSION: Bone cement containing rhbFGF and rhBMP-2 could more effectively increase bone mineral density in patients with OVCF, obtain satisfactory clinical and radiological effects after operation, and significantly improve clinical symptoms.


Assuntos
Proteína Morfogenética Óssea 2 , Fator 2 de Crescimento de Fibroblastos , Fraturas por Compressão , Cifoplastia , Fraturas por Osteoporose , Proteínas Recombinantes , Fraturas da Coluna Vertebral , Fator de Crescimento Transformador beta , Vertebroplastia , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Idoso , Cimentos Ósseos/uso terapêutico , Fraturas por Compressão/tratamento farmacológico , Fraturas por Compressão/cirurgia , Fraturas por Compressão/complicações , Estudos Retrospectivos , Fraturas da Coluna Vertebral/tratamento farmacológico , Fraturas da Coluna Vertebral/cirurgia , Fraturas da Coluna Vertebral/complicações , Fraturas por Osteoporose/tratamento farmacológico , Fraturas por Osteoporose/cirurgia , Fraturas por Osteoporose/etiologia , Cifoplastia/efeitos adversos , Vertebroplastia/efeitos adversos , Fosfatos de Cálcio/uso terapêutico , Resultado do Tratamento
5.
ACS Omega ; 8(50): 48326-48335, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38144075

RESUMO

Recently, there have been reports of lead halide perovskite-based sensors demonstrating their potential for gas sensing applications. However, the toxicity of lead and the instability of lead-based perovskites have limited their applications. This study addressed this issue by developing a H2S gas sensor based on a lead-free CsCu2I3 film prepared using a one-step CVD method. The sensor demonstrated excellent sensing properties, including a high response and selectivity toward H2S, even at low concentrations (0.2 ppm) at room temperature. Furthermore, a reasonable sensing mechanism was proposed. It is suggested that the sensing mechanism sheds light on the role of defects in perovskite materials, the impact of H2S as an electron donor, and the occurrence of reversible chemical reactions. These findings suggest that lead-free CsCu2I3 has great potential in the field of H2S gas sensing.

6.
Antioxidants (Basel) ; 11(10)2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36290791

RESUMO

Obesity and its complications have become serious global health concerns recently and increasing work has been carried out to explicate the underlying mechanism of the disease development. The recognized correlations suggest oxidative stress and inflammation in expanding adipose tissue with excessive fat accumulation play important roles in the pathogenesis of obesity, as well as its associated metabolic syndromes. In adipose tissue, obesity-mediated insulin resistance strongly correlates with increased oxidative stress and inflammation. Nuclear factor erythroid 2-related factor 2 (Nrf2) has been described as a key modulator of antioxidant signaling, which regulates the transcription of various genes coding antioxidant enzymes and cytoprotective proteins. Furthermore, an increasing number of studies have demonstrated that Nrf2 is a pivotal target of obesity and its related metabolic disorders. However, its effects are controversial and even contradictory. This review aims to clarify the complicated interplay among Nrf2, oxidative stress, lipid metabolism, insulin signaling and chronic inflammation in obesity. Elucidating the implications of Nrf2 modulation on obesity would provide novel insights for potential therapeutic approaches in obesity and its comorbidities.

7.
Membranes (Basel) ; 12(6)2022 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35736252

RESUMO

Based on the mathematical modeling and operational optimization studies of reverse osmosis (RO) and multistage flash (MSF) desalination, the structural optimization of the hybrid process was specially studied in this work with the consideration of reducing comprehensive expenses under given operational conditions. Firstly, according to the process mechanism and flowchart of the RO and MSF seawater desalination technologies, seven hybrid structures with different feed conditions were designed, and their connection equations were established for numerical calculation. Then, in order to evaluate the economic performance of the hybrid systems with different structures, the hourly average operational cost equations of RO and MSF processes were established and formulated as the comprehensive evaluation indicators. Next, with a given water production requirement, simulation calculations of the hybrid system with seven different structures were performed. The results show that the hybrid system with the fourth structure has the lowest operational cost of 4.6834 CNY/m3, and at the same time it has the lowest blowdown. However, if we take GOR or production water temperature as the target, the optimal structure of the hybrid system is the fifth or the seventh option. The obtained results are helpful in structural optimization of the hybrid system with aspects of operational cost reduction, maximum GOR, or minimizing the wastewater discharge.

8.
Membranes (Basel) ; 12(5)2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35629804

RESUMO

Focusing on the problems of opaqueness and high energy consumption in coal-fired power plant wastewater recycling processes, this paper studies the simulation and operational optimization of coal-fired power plant wastewater treatment by taking a coal-fired power plant system in Inner Mongolia as an example. Firstly, based on the solution-diffusion theory, pressure drop, and osmotic concentration polarization, a mechanistic model equation for coal-fired power plant wastewater treatment is developed. Secondly, the equation fitness and equation parameters are calibrated to obtain an accurate model. Thirdly, the system is simulated and analyzed so as to obtain the influence and change trajectories of different feed flowrates, temperatures, pressures, and concentrations on various aspects of the system's performance, such as water recovery rate, salt rejection rate, and so on. Finally, in order to reduce the operating cost of the system, an optimization analysis is carried out, with the lowest specific energy consumption and average daily operating cost as optimization goals, and the performance changes of the system before and after optimization under three different working conditions are compared. The results show that adopting the given optimal strategy can significantly reduce the system's operational cost. This research is helpful for the digitization and low-carbon operation of coal-fired power plant wastewater treatment systems.

9.
J Chem Phys ; 155(20): 204701, 2021 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-34852486

RESUMO

In this paper, we designed novel low-symmetry two-dimensional (2D) structures based on conventional XTe (X = Ge, Sn, Pb) thermoelectrics with large average atomic mass. The first-principles calculations combined with Boltzmann transport theory show that the beta-XTe exhibit good stability, high electron carrier mobility, and ultralow ΚL. The subsequent analyses show that the ultralow ΚL stems from the coexistence of resonant bonding, weak bonding, and lone-pair electrons in beta-XTe, which leads to large anharmonicities. On the other hand, the lowest energy conduction band of beta-GeTe and beta-SnTe show the convergence of the low-lying Æ© band, which is the source of the high-power factor in the two systems. The calculated maximum ZT of beta-XTe (X = Ge, Sn, Pb) are 3.08, 1.60, and 0.57 at 300 K, respectively, which is significantly greater than that of the previously reported high-symmetry 2D alpha-XTe and the commercial thermoelectrics. We hope that this work can provide important guidance for the development of thermoelectric materials.

10.
ACS Omega ; 6(26): 16869-16875, 2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34250346

RESUMO

Cadmium-based quantum dots (Cd-QDs) show decent performance for lighting applications due to good color saturation, an excellent high quantum yield, and a narrow full-width at half-maximum. However, the intrinsic toxicity of Cd is a major hindrance to related applications, especially in the biological field. ZnSe, with a band gap of 2.7 eV and lower toxicity than CdSe or CdS, is promising as a blue luminescent material. Herein, we mainly reported the preparation and luminescence properties of nanostructured ZnSe/ZnS multilayer thin films with bright blue photoluminescence. The photoluminescence spectrum contained two emission peaks, located at about 442 nm (near band-edge emission) and 550 nm (defect-related emission), respectively. More importantly, the photoluminescence performance and decay were explored in detail through low-temperature photoluminescence spectra. In addition, the nanostructured ZnSe/ZnS multilayer thin films showed favorable photostability.

11.
Nat Commun ; 12(1): 2655, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33976121

RESUMO

The epigenome has been shown to deteriorate with age, potentially impacting on ageing-related disease. tRNA, while arising from only ˜46 kb (<0.002% genome), is the second most abundant cellular transcript. tRNAs also control metabolic processes known to affect ageing, through core translational and additional regulatory roles. Here, we interrogate the DNA methylation state of the genomic loci of human tRNA. We identify a genomic enrichment for age-related DNA hypermethylation at tRNA loci. Analysis in 4,350 MeDIP-seq peripheral-blood DNA methylomes (16-82 years), identifies 44 and 21 hypermethylating specific tRNAs at study-and genome-wide significance, respectively, contrasting with none hypomethylating. Validation and replication (450k array and independent targeted Bisuphite-sequencing) supported the hypermethylation of this functional unit. Tissue-specificity is a significant driver, although the strongest consistent signals, also independent of major cell-type change, occur in tRNA-iMet-CAT-1-4 and tRNA-Ser-AGA-2-6. This study presents a comprehensive evaluation of the genomic DNA methylation state of human tRNA genes and reveals a discreet hypermethylation with advancing age.


Assuntos
Envelhecimento/genética , Ilhas de CpG/genética , Metilação de DNA , Genoma Humano/genética , RNA de Transferência/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Neoplasias/genética , Neoplasias/patologia , Especificidade de Órgãos/genética , Adulto Jovem
12.
J Clin Neurosci ; 85: 41-48, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33581788

RESUMO

To investigate the safety, accuracy and indications of traditional and novel cortical bone screws placement for osteoporosis lumbar spine, 4 lumbar vertebra specimens (2 males and 2 females) were used for this study. After the computed tomography scanning data of the above anatomical specimens were three-dimensional (3D) reconstructed, one side of each anatomical specimen was randomly chosen to place traditional cortical bone screws, and the other side received novel technical placement. The safety screw trajectory was designed, and a 3D navigation template complementary to the surface anatomical structure of lumbar isthmus lateral margin-vertebral plate-spinous process part was established. The designed supporting navigation template was substantialized, and the navigation template replicated different cortical bone screw trajectory at different sides of the same one lumbar vertebra. Forty cortical bone screws were firstly placed in 3D printed vertebra and then 40 were placed in real anatomical specimens. In 3D printed specimens, the success rates of screw placement with navigation template using traditional and novel techniques were both 100%. While in anatomical specimens, the success rate of screw placement using traditional and novel navigation template was 97.5% (one out of 40 went wrong). Therefore, it is safe, accurate and reliable to place traditional and novel cortical bone screws on osteoporosis lumbar spine using 3D printed navigation template. Traditional and novel screw placement methods should be flexibly applied or combined according to specific sequence and form of vertebra.


Assuntos
Imageamento Tridimensional/métodos , Neuronavegação/métodos , Osteoporose/cirurgia , Impressão Tridimensional , Fusão Vertebral/métodos , Idoso , Cadáver , Osso Cortical/cirurgia , Feminino , Humanos , Vértebras Lombares/cirurgia , Masculino , Pessoa de Meia-Idade , Parafusos Pediculares , Tomografia Computadorizada por Raios X/métodos
13.
EBioMedicine ; 57: 102835, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32574963

RESUMO

BACKGROUND: Little is known about whether UVB can directly influence epigenetic regulatory pathways to induce cutaneous squamous cell carcinoma (CSCC). This study aimed to identify epigenetic-regulated signalling pathways through global methylation and gene expression profiling and to elucidate their function in CSCC development. METHODS: Global DNA methylation profiling by reduced representation bisulfite sequencing (RRBS) and genome-wide gene expression analysis by RNA sequencing (RNA-seq) in eight pairs of matched CSCC and adjacent normal skin tissues were used to investigate the potential candidate gene(s). Clinical samples, animal models, cell lines, and UVB irradiation were applied to validate the mechanism and function of the genes of interest. FINDINGS: We identified the downregulation of the TGF-ß/BMP-SMAD-ID4 signalling pathway in CSCC and increased methylation of inhibitor of DNA binding/differentiation 4 (ID4). In normal human and mouse skin tissues and cutaneous cell lines, UVB exposure induced ID4 DNA methylation, upregulated DNMT1 and downregulated ten-eleven translocation (TETs). Similarly, we detected the upregulation of DNMT1 and downregulation of TETs accompanying ID4 DNA methylation in CSCC tissues. Silencing of DNMT1 and overexpression of TET1 and TET2 in A431 and Colo16 cells led to increased ID4 expression. Finally, we showed that overexpression of ID4 reduced cell proliferation, migration, and invasion, and increased apoptosis in CSCC cell lines and reduced tumourigenesis in mouse models. INTERPRETATION: The results indicate that ID4 is downregulated by UVB irradiation via DNA methylation. ID4 acts as a tumour suppressor gene in CSCC development. FUNDING: CAMS Innovation Fund for Medical Sciences (CIFMS) (2016-I2M-3-021, 2017-I2M-1-017), the Natural Science Foundation of Jiangsu Province (BK20191136), and the Fundamental Research Funds for the Central Universities (3332019104).


Assuntos
Carcinoma de Células Escamosas/genética , DNA (Citosina-5-)-Metiltransferase 1/genética , Proteínas de Ligação a DNA/genética , Proteínas Inibidoras de Diferenciação/genética , Oxigenases de Função Mista/genética , Proteínas Proto-Oncogênicas/genética , Neoplasias Cutâneas/genética , Animais , Carcinogênese/efeitos da radiação , Carcinoma de Células Escamosas/etiologia , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos da radiação , DNA (Citosina-5-)-Metiltransferase 1/antagonistas & inibidores , Metilação de DNA/efeitos da radiação , Dioxigenases , Progressão da Doença , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Humanos , Camundongos , Neoplasias Induzidas por Radiação , RNA-Seq , Transdução de Sinais/efeitos da radiação , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/patologia , Fator de Crescimento Transformador beta/genética , Raios Ultravioleta/efeitos adversos
15.
Sensors (Basel) ; 19(13)2019 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-31324036

RESUMO

In this paper, we report a wireless gas sensor based on surface acoustic waves (SAW). For room temperature detection of oxygen gas, a novel nanostructured ZnxFeyO gas-sensitive film was deposited on the surface of a SAW resonator by an oblique magnetron co-sputtering method. The measurements of X-ray diffraction (XRD) and a scanning electron microscope (SEM) showed that the crystal phase composition and the microstructures of ZnxFeyO films were significantly affected by the content of Fe. The experimental results showed that the sensors had a good response to O2 at room temperature. The max frequency shift of the sensors reached 258 kHz as the O2 partial pressure was 20%. Moreover, X-ray photoelectron spectroscopy (XPS) was performed to analyze the role of Fe in the sensitization process of the ZnxFeyO film. In addition, the internal relationship between the Fe content of the film and the sensitivity of the sensor was presented and discussed. The research indicates that the nanostructured ZnxFeyO film has a good potential for room temperature O2 gas detection applications.

16.
J Exp Clin Cancer Res ; 38(1): 261, 2019 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-31200735

RESUMO

BACKGROUND & AIMS: Although the prognosis of patients with occult hepatitis B virus (HBV) infection (OBI) is usually benign, a small portion may undergo cirrhosis and subsequently hepatocellular carcinoma (HCC). We studied the mechanism of life-long Integration of virus DNA into OBI host's genome, of which may induce hepatocyte transformation. METHODS: We applied HBV capture sequencing on single cells from an OBI patient who, developed multiple HCC tumors and underwent liver resection in May 2013 at Tongji Hospital in China. Despite with the undetectable virus DNA in serum, we determined the pattern of viral integration in tumor cells and adjacent non-tumor cells and obtained the details of the viral arrangement in host genome, and furthermore the HBV integrated region in cancer genome. RESULTS: HBV captured sequencing of tissues and individual cells revealed that samples from multiple tumors shared two viral integration sites that could affect three host genes, including CSMD2 on chr1 and MED30/EXT1 on chr8. Whole genome sequencing further indicated one hybrid chromosome formed by HBV integrations between chr1 and chr8 that was shared by multiple tumors. Additional 50 poorly differentiated liver tumors and the paired adjacent non-tumors were evaluated and functional studies suggested up-regulated EXT1 expression promoted HCC growth. We further observed that the most somatic mutations within the tumor cell genome were common among the multiple tumors, suggesting that HBV associated, multifocal HCC is monoclonal in origin. CONCLUSION: Through analyzing the HBV integration sites in multifocal HCC, our data suggested that the tumor cells were monoclonal in origin and formed in the absence of active viral replication, whereas the affected host genes may subsequently contribute to carcinogenesis.


Assuntos
Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/patologia , Vírus da Hepatite B , Hepatite B Crônica/complicações , Hepatite B Crônica/virologia , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/patologia , Integração Viral , Biópsia , Carcinoma Hepatocelular/diagnóstico por imagem , Linhagem Celular Tumoral , Mapeamento Cromossômico , DNA Viral/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Heterogeneidade Genética , Haplótipos , Vírus da Hepatite B/genética , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , N-Acetilglucosaminiltransferases/genética , Carga Tumoral
17.
ACS Appl Mater Interfaces ; 11(2): 2071-2081, 2019 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-30566321

RESUMO

The ever-growing demand for sustainable and renewable power sources has led to the development of novel materials for photocatalytic water splitting, but enhancing the photocatalytic efficiency remains a core problem. Herein, we report a conceptual effective and experimental confirmed strategy for SnO2 quantum dot (QD) interspersed multiphase (rutile, anatase) TiO2 nanorod arrays (SnO2/RA@TiO2 NRs) to immensely enhance the carrier separation for highly efficient water splitting by merging simultaneously the QD, multiphase, and heterojunction approaches. Under this synergistic effect, a doping ratio of 25% SnO2 QD interspersed into multiphase TiO2 NRs exhibited a superior optical adsorption and excellent photocurrent density (2.45 mA/cm2 at 1.0 V), giving rise to a largely enhanced incident light to current efficiency in the UV region (45-50%). More importantly, this material-based device can act as power supply with a voltage of ∼2.8 V after illumination, which can automatically self-recharge by reacting with oxygen vacancy and water molecule to realize reuse. The current study provides a new paradigm about heightening the carrier separation extent of QD interspersed multiphase heterojunctions, fabricating a new solar-energy-converting material/device, and achieving a highly photocatalytic water splitting/self-charging battery-like application.

18.
Int J Mol Sci ; 19(5)2018 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-29747401

RESUMO

Cytosine DNA methylation is a critical epigenetic mechanism in the silencing of transposable elements, imprinting and regulating gene expression. However, little is known about the potential role of mC in response to heat stress. To determine and explore the functions of the dynamic DNA methylome during heat stress, we characterized single-base resolution methylome maps of Brassica rapa and assessed the dynamic changes of mC under heat stress using whole genome bisulfite sequencing. On average, the DNA methylation levels of CG, CHG and CHH are 39.3%, 15.38% and 5.24% in non-heading Chinese cabbage (NHCC), respectively. We found that the patterns of methylation are similar to other eudicot plants, but with higher CHH methylation levels. Further comparative analysis revealed varying patterns for three sequence contexts (mCG, mCHG and mCHH) under heat stress indicating context- and position-dependent methylation regulation. DNA methylation near the TSS and TES may be closely associated with methylation-dependent transcriptional silencing. Association analysis of differential methylation and differential gene expression revealed a different set of methDEGs involved at early and late stages under heat stress. The systemic characterization of the dynamic DNA methylome during heat stress will improve our understanding of the mechanism of epigenetic regulation under heat stress.


Assuntos
Brassica rapa/genética , Brassica rapa/fisiologia , Metilação de DNA/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Resposta ao Choque Térmico/genética , Estresse Fisiológico/genética , Adaptação Fisiológica/efeitos dos fármacos , Sequência de Bases , Sequência Conservada/genética , Inibidores Enzimáticos/farmacologia , Genes de Plantas , Metiltransferases/antagonistas & inibidores , Metiltransferases/metabolismo , Modelos Biológicos , Anotação de Sequência Molecular , RNA de Plantas/genética , Transdução de Sinais/genética
19.
J Colloid Interface Sci ; 520: 19-24, 2018 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-29525500

RESUMO

In this work, a flexible resistive switching memory device based on ZnO film was fabricated using a foldable Polyethylene terephthalate (PET) film as substrate while Ag and Ti acts top and bottom electrode. Our as-prepared device represents an outstanding nonvolatile memory behavior with good "write-read-erase-read" stability at room temperature. Finally, a physical model of Ag conductive filament is constructed to understanding the observed memory characteristics. The work provides a new way for the preparation of flexible memory devices based on ZnO films, and especially provides an experimental basis for the exploration of high-performance and portable nonvolatile resistance random memory (RRAM).

20.
Nat Commun ; 9(1): 8, 2018 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-29295990

RESUMO

Integrating epigenetic data with genome-wide association study (GWAS) results can reveal disease mechanisms. The genome sequence itself also shapes the epigenome, with CpG density and transcription factor binding sites (TFBSs) strongly encoding the DNA methylome. Therefore, genetic polymorphism impacts on the observed epigenome. Furthermore, large genetic variants alter epigenetic signal dosage. Here, we identify DNA methylation variability between GWAS-SNP risk and non-risk haplotypes. In three subsets comprising 3128 MeDIP-seq peripheral-blood DNA methylomes, we find 7173 consistent and functionally enriched Differentially Methylated Regions. 36.8% can be attributed to common non-SNP genetic variants. CpG-SNPs, as well as facilitative TFBS-motifs, are also enriched. Highlighting their functional potential, CpG-SNPs strongly associate with allele-specific DNase-I hypersensitivity sites. Our results demonstrate strong DNA methylation allelic differences driven by obligatory or facilitative genetic effects, with potential direct or regional disease-related repercussions. These allelic variations require disentangling from pure tissue-specific modifications, may influence array studies, and imply underestimated population variability in current reference epigenomes.


Assuntos
Metilação de DNA , Doença/genética , Variação Genética , Estudo de Associação Genômica Ampla/métodos , Alelos , Ilhas de CpG/genética , Epigênese Genética , Predisposição Genética para Doença/genética , Genoma Humano/genética , Haplótipos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Polimorfismo de Nucleotídeo Único , Fatores de Risco
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