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1.
Angew Chem Int Ed Engl ; : e202412983, 2024 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-39180516

RESUMO

Disordered polymer chain entanglements within all-polymer blends limit the formation of optimal donor-acceptor phase separation. Therefore, developing effective methods to regulate morphology evolution is crucial for achieving optimal morphological features in all-polymer organic solar cells (APSCs). In this study, two isomers, 4,5-difluorobenzo-c-1,2,5-thiadiazole (SF-1) and 5,6-difluorobenzo-c-1,2,5-thiadiazole (SF-2), were designed as solid additives based on the widely-used electron-deficient benzothiadiazole unit in nonfullerene acceptors. The incorporation of SF-1 or SF-2 into PM6:PY-DT blend induces stronger molecular packing via molecular interaction, leading to the formation of continuous interpenetrated networks with suitable phase-separation and vertical distribution. Furthermore, after treatment with SF-1 and SF-2, the exciton diffusion lengths for PY-DT films are extended to over 40 nm, favoring exciton diffusion and charge transport. The asymmetrical SF-2, characterized by an enhanced dipole moment, increases the power conversion efficiency (PCE) of PM6:PY-DT-based device to 18.83% due to stronger electrostatic interactions. Moreover, a ternary device strategy boosts the PCE of SF-2-treated APSC to over 19%. This work not only demonstrates one of the best performances of APSCs but also offers an effective approach to manipulate the morphology of all-polymer blends using rational-designed solid additives.

2.
Angew Chem Int Ed Engl ; : e202409421, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39136328

RESUMO

Realizing high-rate and high-capacity features of Lihium-organic batteries is essential for their practical use but remains a big challenge, which is due to the instrinsic poor conductivity, limited redox kinetics and low utility of organic electrode mateials. This work presents a well-designed donor-acceptor Covalent Organic Framework (COFs) with extended conjugation, mesoscale porosity, and dual redox-active centers to promote fast charge transfer and multi-electron processes. As anticipated, the prepared cathode with benzo [1,2-b:3,4-b':5,6-b''] trithiophene (BTT) as p-type and pyrene-4,5,9,10-tetraone (PTO) as n-type material (BTT-PTO-COF) delivers impressive specific capacity (218 mAh g-1 and 275 mAh g-1 at 0.2 A g-1 in ether-based and carbonate-based electrolyte respectively) and outstanding rate capability (79 mAh g-1 at 50 A g-1 in ether-based electrolyte and 124 mAh g-1 at 10 A g-1 in carbonate-based electrolyte). Moreover, the potential of BTT-PTO-COF electrode for prototype batteries has been demonstrated by full cells of dual-ion batteries, which attain comparable electrochemical performances to the half cells. Moreover, mechanism studies combining ex-situ characterization and theoratical calculations reveal the efficient dual-ion storage process and facile charge transfer of BTT-PTO-COF. This work not only expands the diversity of redox-active COFs but also provide concept of structure design for high-rate and high-capacity organic electrodes.

3.
PLoS One ; 19(5): e0302741, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38758774

RESUMO

In the context of integrating sports and medicine domains, the urgent resolution of elderly health supervision requires effective data clustering algorithms. This paper introduces a novel higher-order hybrid clustering algorithm that combines density values and the particle swarm optimization (PSO) algorithm. Initially, the traditional PSO algorithm is enhanced by integrating the Global Evolution Dynamic Model (GEDM) into the Distribution Estimation Algorithm (EDA), constructing a weighted covariance matrix-based GEDM. This adapted PSO algorithm dynamically selects between the Global Evolution Dynamic Model and the standard PSO algorithm to update population information, significantly enhancing convergence speed while mitigating the risk of local optima entrapment. Subsequently, the higher-order hybrid clustering algorithm is formulated based on the density value and the refined PSO algorithm. The PSO clustering algorithm is adopted in the initial clustering phase, culminating in class clusters after a finite number of iterations. These clusters then undergo the application of the density peak search algorithm to identify candidate centroids. The final centroids are determined through a fusion of the initial class clusters and the identified candidate centroids. Results showcase remarkable improvements: achieving 99.13%, 82.22%, and 99.22% for F-measure, recall, and precision on dataset S1, and 75.22%, 64.0%, and 64.4% on dataset CMC. Notably, the proposed algorithm yields a 75.22%, 64.4%, and 64.6% rate on dataset S, significantly surpassing the comparative schemes' performance. Moreover, employing the text vector representation of the LDA topic vector model underscores the efficacy of the higher-order hybrid clustering algorithm in efficiently clustering text information. This innovative approach facilitates swift and accurate clustering of elderly health data from the perspective of sports and medicine integration. It enables the identification of patterns and regularities within the data, facilitating the formulation of personalized health management strategies and addressing latent health concerns among the elderly population.


Assuntos
Algoritmos , Humanos , Análise por Conglomerados , Idoso , Gestão da Informação em Saúde/métodos , Medicina Esportiva/métodos , Esportes
4.
Adv Mater ; : e2311541, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38551322

RESUMO

2D conjugated polymers (2DCPs) possess extended in-plane π-conjugated lattice and out-of-plane π-π stacking, which results in enhanced electronic performance and potentially unique band structures. These properties, along with predesignability, well-defined channels, easy postmodification, and order structure attract extensive attention from material science to organic electronics. In this review, the recent advance in the interfacial synthesis and conductivity tuning strategies of 2DCP thin films, as well as their application in organic electronics is summarized. Furthermore, it is shown that, by combining topology structure design and targeted conductivity adjustment, researchers have fabricated 2DCP thin films with predesigned active groups, highly ordered structures, and enhanced conductivity. These films exhibit great potential for various thin-film organic electronics, such as organic transistors, memristors, electrochromism, chemiresistors, and photodetectors. Finally, the future research directions and perspectives of 2DCPs are discussed in terms of the interfacial synthetic design and structure engineering for the fabrication of fully conjugated 2DCP thin films, as well as the functional manipulation of conductivity to advance their applications in future organic electronics.

5.
Sensors (Basel) ; 24(2)2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38257565

RESUMO

Surface-enhanced Raman scattering (SERS) spectroscopy is a powerful technology in trace analysis. However, the wide applications of SERS in practice are limited by the expensive substrate materials and the complicated preparation processes. Here we report a simple and economical galvanic-replacement-assisted synthesis route to prepare Ag nanoparticles on Cu(0) foil (nanoAg@Cu), which can be directly used as SERS substrate. The fabrication process is fast (ca. 10 min) and easily scaled up to centimeters or even larger. In addition, the morphology of the nanoAg@Cu (with Ag particles size from 30 nm to 160 nm) can be adjusted by various additives (e.g., amino-containing ligands). Finally, we show that the as-prepared nanoAg@Cu can be used for SERS characterization of two-dimensional polymers, and ca. 298 times relative enhancement of Raman intensity is achieved. This work offers a simple and economical strategy for the scalable fabrication of silver-based SERS substrate in thin film analysis.

6.
Chem Asian J ; 19(3): e202301076, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38151907

RESUMO

Organic thin-film transistors (OTFTs) as a vital component among transistors have shown great potential in smart sensing, flexible displays, and bionics due to their flexibility, biocompatibility and customizable chemical structures. Even though linear conjugated polymer semiconductors are common for constructing channel materials of OTFTs, advanced materials with high charge carrier mobility, tunable band structure, robust stability, and clear structure-property relationship are indispensable for propelling the evolution of OTFTs. Two-dimensional conjugated polymers (2DCPs), featured with conjugated lattice, tailorable skeletons, and functional porous structures, match aforementioned criteria closely. In this review, we firstly introduce the synthesis of 2DCP thin films, focusing on their characteristics compatible with the channels of OTFTs. Subsequently, the physics and operating mechanisms of OTFTs and the applications of 2DCPs in OTFTs are summarized in detail. Finally, the outlook and perspective in the field of OTFTs using 2DCPs are provided as well.

7.
Opt Lett ; 48(24): 6432-6435, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38099766

RESUMO

To the best of our knowledge, this paper first reports ErF3 microcrystals controllably deposited in perfluoride glass using phase-separation engineering techniques. The sample exhibited strong upconversion red-light emission owing to the small distance between Er3+ ions and low phonon energy (585 cm-1). The sample has a high red/green ratio of up to 18.6, which, to our knowledge, is the highest reported value in Er3+-doped fluoride glass ceramics. Furthermore, the sample has a long fluorescence lifetime (3.18 ms @660 nm), good color saturation (0.6255,0.3707), and good thermal stability (Δ E=0.31e V). Therefore, this sample has the potential for application across multiple fields, such as color display, visible laser, and lighting.

8.
Phys Chem Chem Phys ; 25(37): 25458-25464, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37712287

RESUMO

Improving the solar-to-hydrogen efficiency has always been a significant topic in the field of photocatalysis. Based on first-principles calculations, herein, we propose multiple strategies to improve the photocatalytic properties of 2D arsenic sesquichalcogenides for full water splitting. The new configurations As2STe2 and As2SeTe2 monolayers, derived from the As2Te3 monolayers by surface modification, are manifested to be typical infrared-light driven photocatalysts. Notably, under the built-in electric field, As2STe2 and As2SeTe2 monolayers can fulfil overall water splitting and the predicted solar-to-hydrogen efficiencies even reach up to 36.19% and 29.36%, respectively. The Gibbs free energy calculations indicate that the OER can be successfully driven under light irradiation. In addition, the overpotentials can provide most of the energy for HER when illuminated, especially for As2STe2 with the . In addition, both As2S3 and As2Se3 monolayers are capable of satisfying the conditions for photocatalytic water splitting. Furthermore, the band gaps of As2Se3 and As2S3 can dramatically be narrowed by increasing the number of layers and doping, respectively. These findings provide a theoretical basis for As2X3 monolayers to achieve efficient photocatalytic water splitting.

9.
Phys Chem Chem Phys ; 25(25): 16896-16907, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37318781

RESUMO

van der Waals heterostructures (vdWHs) open the possibility of creating novel semiconductor materials at the atomic scale that demonstrate totally new physics and enable unique functionalities, and have therefore attracted great interest in the fields of advanced electronic and optoelectronic devices. However, the interactions between metals and vdWHs semiconductors require further investigation as they directly affect or limit the advancement of high-performance electronic devices. Here we study the contact behavior of MoS2/WSe2 vdWHs in contact with a series of bulk metals using ab initio electronic structure calculations and quantum transport simulations. Our study shows that dual transmission paths for electrons and holes exist at the metal-MoS2/WSe2 hetero-bilayer interfaces. In addition, the metal-induced bandgap state (MIGS) of the original monolayer disappears due to the creation of the heterolayer, which weakens the Fermi level pinning (FLP) effect. We also find that the creation of the heterolayer causes a change in the Schottky barrier height (SBH) of the non-ohmic contact systems, whilst this does not occur so easily in the ohmic contact systems. In addition, our results indicate that when Al, Ag and Au are in contact with a MoS2/WSe2 hetero-bilayer semiconductor, a low contact barrier exists throughout the whole transmission process causing the charge to tunnel to the MoS2 layer, irrespective of whether the MoS2 is in contact with the metals as the nearest layer or as the next-nearest layer. Our work not only offers new insights into electrical contact issues between metals and hetero-bilayer semiconductors, but also provides guidance for the design of high-performance vdWHs semiconductor devices.

10.
Langmuir ; 39(25): 8769-8778, 2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37307594

RESUMO

Incorporating inorganic components into organic molecular devices offers one novel alternative to address challenges existing in the fabrication and integration of nanoscale devices. In this study, using a theoretical method of density functional theory combined with the nonequilibrium Green's function, a series of benzene-based molecules with group III and V substitutions, including borazine molecule and XnB3-nN3H6 (X = Al or Ga, n = 1-3) molecules/clusters, are constructed and investigated. An analysis of electronic structures reveals that the introduction of inorganic components effectively reduces the energy gap between the highest occupied molecular orbital and the lowest unoccupied molecular orbital, albeit at the cost of reduced aromaticity in these molecules/clusters. Simulated electronic transport characteristics demonstrate that XnB3-nN3H6 molecules/clusters coupled between metal electrodes exhibit lower conductance compared to prototypical benzene molecule. Additionally, the choice of metal electrode materials significantly impacts the electronic transport properties, with platinum electrode devices displaying distinct behavior compared to silver, copper, and gold electrode devices. This distinction arises from the amount of transferred charge, which modulates the alignment between molecular orbitals and the Fermi level of the metal electrodes by shifting the molecular orbitals in energy. These findings provide valuable theoretical insights for the future design of molecular devices incorporating inorganic substitutions.

11.
Autophagy ; 19(8): 2257-2274, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36779599

RESUMO

Porcine reproductive and respiratory syndrome virus (PRRSV) is a typical immunosuppressive virus devastating the global swine industry. DEAD-box helicases (DDXs) are a family of ATP-dependent RNA helicases that are predominantly implicated in modulating cellular RNA metabolism. Meanwhile, a growing number of studies have suggested that some DDXs are associated with innate immunity and virus infection, so they are considered potential antiviral targets. Herein, we screened 40 DDXs and found that ectopic expression of DDX10 exhibited a significant anti-PRRSV effect, while DDX10 knockdown promoted PRRSV proliferation. Further analysis revealed that DDX10 positively regulates type I interferon production, which may contribute to its anti-PRRSV effect. Interestingly, PRRSV infection promoted DDX10 translocation from the nucleus to the cytoplasm for macroautophagic/autophagic degradation to block the antiviral effect of DDX10. By screening PRRSV-encoded proteins, we found that the viral envelope (E) protein interacted with DDX10. In line with the autophagic degradation of DDX10 during PRRSV infection, E protein could induce autophagy and reduce DDX10 expression in wild-type cells, but not in ATG5 or ATG7 knockout (KO) cells. When further screening the cargo receptors for autophagic degradation, we found that SQSTM1/p62 (sequestosome 1) interacted with both DDX10 and E protein, and E protein-mediated DDX10 degradation was almost entirely blocked in SQSTM1 KO cells, demonstrating that E protein degrades DDX10 by promoting SQSTM1-mediated selective autophagy. Our study reveals a novel mechanism by which PRRSV escapes host antiviral innate immunity through selective autophagy, providing a new target for developing anti-PRRSV drugs.Abbreviations: ACTB: actin beta; ATG: autophagy related; co-IP: co-immunoprecipitation; CQ: chloroquine; DDX10: DEAD-box helicase 10; E: envelope; EGFP: enhanced green fluorescent protein; hpi: hours post infection; hpt: hours post transfection; IFA: indirect immunofluorescence assay; IFN-I: type I IFN; IFNB/IFN-ß: interferon beta; IRF3: interferon regulatory factor 3; ISGs: interferon-stimulated genes; KO: knockout; MAP1LC3B/LC3: microtubule associated protein 1 light chain 3 beta; mAb: monoclonal antibody; MOI: multiplicity of infection; NBR1: NBR1 autophagy cargo receptor; NFKB/NF-κB: nuclear factor kappa B; OPTN: optineurin; ORF: open reading frame; PRRSV: porcine reproductive and respiratory syndrome virus; SeV: sendai virus; siRNA: small interfering RNA; SQSTM1/p62: sequestosome 1; TCID50: 50% tissue culture infective dose; WT: wild type.


Assuntos
Interferon Tipo I , Síndrome Respiratória e Reprodutiva Suína , Vírus da Síndrome Respiratória e Reprodutiva Suína , Suínos , Animais , Vírus da Síndrome Respiratória e Reprodutiva Suína/metabolismo , Antivirais/farmacologia , Proteína Sequestossoma-1/metabolismo , Transdução de Sinais/genética , Autofagia , RNA Helicases DEAD-box/genética , RNA Helicases DEAD-box/metabolismo , Interferon beta/metabolismo , Interferon Tipo I/metabolismo , NF-kappa B/metabolismo
12.
Artigo em Inglês | MEDLINE | ID: mdl-35805419

RESUMO

The adoption of conservation tillage technology can improve the production efficiency of black soils (mollisols), and it has great significance to ensure the sustainable development of agriculture. This paper takes farmers in the black soil region of Jilin Province as the research object, uses 442 survey data of farmers in seven municipal areas in the black soil region of Jilin Province, constructs a logistic-ISM model, first determines the influencing factors of farmers' adoption of conservation tillage technology, and then analyzes the hierarchical structure of each influencing factor. The results show that: (1) among the eight significant influencing factors of farmers' adoption of conservation tillage technology, age, whether they know the government's subsidies for conservation tillage and the number of labor force are the deep-rooted factors; (2) Education level, whether you know that the government is promoting conservation tillage, and the planting area are intermediate level factors; (3) whether they have received the technical services of conservation tillage and whether the cultivated land is scattered is the direct factors. Based on the significance analysis of the influencing factors of farmers' adoption of conservation tillage technology and the research on the action mechanism of the influencing factors of farmers' adoption of conservation tillage technology, this paper puts forward policy suggestions to improve the extension system of conservation tillage technology, improve the implementation of land transfer and subsidy policies, strengthen the ability of rural socialized services, and strengthen the publicity of black soils protection.


Assuntos
Fazendeiros , Solo , Agricultura/métodos , China , Humanos , Tecnologia
13.
Phys Chem Chem Phys ; 24(17): 10095-10100, 2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-35416191

RESUMO

Two-dimensional (2D) Dirac materials have been a research hotspot due to their intriguing properties, such as high carrier mobility and ballistic charge transport. Here, we demonstrate that the B2S3 monolayer with a hexagonal structure, which has been reported as a photocatalyst, can be tuned to new 2D Dirac materials by doping atoms. The Young's modulus can reach 65.23 N m-1, indicating that the monolayer can be used as a buffer materials. The electronic structures of the pristine B2S3 monolayer show that some Dirac points appear but do not occur exactly on the Fermi level (EF). Fortunately, we find that the Dirac cone can be tuned to the EF by doping C, N, or Sn atoms. The C-doped B2S3 monolayer can be a half-metallic Dirac material, which has significant potential application in spintronics. For N- and Sn-doped B2S3 monolayers, the typical kagome bands are formed near the EF, which arise from three molecular orbitals hybridized by B, S, and N (Sn) atoms. These outstanding properties render the doped B2S3 monolayers promising 2D Dirac materials for future nanoelectronic devices.

14.
Phys Chem Chem Phys ; 23(15): 9440-9447, 2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33885100

RESUMO

The van der Waals heterostructures (vdWHs) create a multi-purpose platform to design unique structures for efficient photovoltaic and optoelectronic applications. In this study, on the basis of the first-principles calculations, we present a type-II semiconducting MoSSe/g-SiC vdWH with a moderate bandgap value of 1.31 eV. In particular, the large conduction band offset of 1.18 eV and valence band offset of 0.90 eV are distinguished, which can act as powerful driving forces to promote interlayer charge transfer. Moreover, MoSSe/g-SiC vdWH possesses high carrier mobilities and anisotropic transport properties with a larger transport current along the zigzag direction. More importantly, tensile strain can transform indirect into direct band gap and enhance the visible-light absorption while sustaining type-II band alignment. These results reveal the new physical nature of MoSSe/g-SiC vdWH and demonstrate its practical application potential in photovoltaics and optoelectronic nanodevices.

15.
Opt Express ; 29(7): 10893-10902, 2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33820212

RESUMO

We theoretically investigate the photodissociation dynamics of H2+ using the methodology of ultrafast X-ray photoelectron diffraction (UXPD). We use a femtosecond infrared pulse to prompt a coherent excitation from the molecular vibrational state (v = 9) of the electronic ground state (1sσg) and then adopt another time-delayed attosecond X-ray pulse to probe the dynamical properties. We have calculated photoionization momentum distributions by solving the non-Born-Oppenheimer time-dependent Schrödinger equation (TDSE). We unambiguously identify the phenomena associated with the g - u symmetry breakdown in the time-resolved photoelectron diffraction spectra. Using the two-center interference model, we can determine the variation in nuclear spacing with high accuracy. In addition, we use a strong field approximation (SFA) model to interpret the UXPD profile, and the SFA simulations can reproduce the TDSE results in a quantitative way.

16.
Nanotechnology ; 32(22)2021 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-33601348

RESUMO

Metal-free semiconductors with desirable characteristics have recently gained great attention in the field of hydrogen generation. The non-metal material B2S3has two phases, hexagonal B2S3(h-B2S3) and orthorhombic B2S3(o-B2S3), which compose a novel class of 2D materials. Bothh-B2S3ando-B2S3monolayers are direct semiconductors with bandgaps of 2.89 and 3.77 eV by the Heyd-Scuserria-Ernzerhof (HSE) function, respectively. Under appropriate uniaxial strain (1%), the bandgap ofh-B2S3can be decreased to 2.8 eV. The carrier mobility can reach 1160 cm2V-1s-1, supporting the fast migration of photo-induced carriers. Most importantly, the band edges of bothh-B2S3ando-B2S3cover the reduction and oxidation levels for water splitting. We explore the process of photocatalytic water splitting onh-B2S3monolayers by analyzing the feasibility of the decomposition of H2O and the generation of H2. The results indicate that the special mesoporous structure of B2S3is helpful for photocatalytic hydrogen production. The new nanomaterial, B2S3, offers great promise as a metal-free photocatalyst due to its tunable bandgaps, its useful band edges, and its other excellent electronic properties.

17.
J Phys Chem A ; 124(51): 10678-10686, 2020 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-33302627

RESUMO

The aliphatic Claisen rearrangement of allyl vinyl ether has attracted great interest for its broad applications in chemical synthesis and biosynthesis. Although it is well agreed that this reaction proceeds via a concerted, "chair-like" transition state, certain inconsistencies of kinetic isotope effect (KIE) data between experimental measurements and theoretical simulations or between independent experiments indicate that the nature and mechanism of this important reaction need to be investigated in more detail. In order to verify two independent sets of experimental data, we present theoretical calculations on heavy-atom KIE values of alipahtic Claisen rearrangement, using our recently developed path-integral method with the second-order Kleinert's variational perturbation theory, which goes beyond the traditional method for computing KIE values by employing the Bigeleisen equation. Amazingly, the results demonstrate that both sets of experimental measurements are correct, while the inconsistency originates from the fact that the aliphatic Claisen rearrangement undergoes similar but different mechanisms in gas and solution phases. Different experimental conditions will alter the actual reactant state by tuning the population distribution of reactant conformers. According to the comparison between experimental and theoretical results, a more clear reaction mechanism of aliphatic Claisen rearrangement is revealed.

18.
Front Neurol ; 11: 607646, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33329370

RESUMO

Ankylosing spondylitis (AS) mainly affects the axial skeleton and is an important factor leading to chronic lower back pain in young individuals. However, few studies have explored alterations of brain gray matter volume in AS patients. The purpose of the present study was to describe brain gray matter abnormalities associated with AS pain. A total of 61 AS patients and 52 healthy controls (HCs) were included in this study. Using voxel-based morphometrics, we detected abnormal gray matter volume in AS patients. Based on the voxel-wise analysis, the gray matter volume in the left putamen of the AS group was increased significantly compared with that of the HC group. In addition, we found that the gray matter volume of the left putamen was positively correlated with the duration of AS and total back pain scores, whereas it was not significantly correlated with Bath Ankylosing Spondylitis Disease Activity Index scores, C-reactive protein, or erythrocyte sedimentation rate in AS patients. Taken together, our findings improve our understanding of the neural substrates of pain in AS and provide evidence of AS-related neurological impairment. Hence, further investigation of the pathophysiology of the left putamen in AS is warranted.

19.
Clin Chim Acta ; 510: 483-487, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32795545

RESUMO

BACKGROUND: Gout is an inflammatory disease characterized by the deposition of monosodium urate (MSU) in synovial fluid and other tissues. Many studies have shown that the activation of coagulation system had been proposed correlated with systemic inflammation. The concentrations of plasma fibrinogen and D-dimer are increased in abnormal coagulation, emerging as available indicators to predict systemic inflammation. The aim of this study is to reveal the predictive value of plasma fibrinogen, D-dimer in the disease activity of gout patients. METHODS: This retrospective study included 334 gout patients and 101 age- and gender- matched healthy controls. The gout patients were divided into two groups according to the gout activity score (GAS = 0.09 × last 12 month attacks + 1.01 × sUA + 0.34 × VAS patient + 0.53 × ln(1 + tophi number). The remission group included 46 patients with GAS of lower than 2.5 and the active group included 288 patients with GAS of 2.5 or higher. Clinical and laboratory data were recorded. The correlations between plasma fibrinogen, D-dimer and GAS were analyzed by Spearman's correlation analysis and Partial correlation analysis. Receiver operating characteristic (ROC) was used to evaluate the diagnostic value for the active group compared with remission group. The predictive value of fibrinogen, D-dimer to the disease activity of gout patients was tested by Binary logistic regression analysis. RESULTS: Plasma fibrinogen and D-dimer in gout patients (3.66 (2.88, 5.20), 0.29 (0.22, 0.80)) were increased as compared with the control group (2.88 (2.51, 3.24), 0.22 (0.22, 0.32), both P < 0.001). Fibrinogen and D-dimer in active group (3.91 (3.00, 5.53), 0.34 (0.22, 0.86)) were higher than those in remission group (2.88 (2.34, 3.22), 0.22 (0.22, 0.26), both P < 0.001)). Plasma fibrinogen, D-dimer, ESR and CRP were positively correlated with GAS (r = 0.606, r = 0.419, r = 0.570, r = 0.440, all P < 0.001). ROC curve showed fibrinogen yielded a highest AUC than D-dimer, ESR, CRP. In addition, the optimal cutoff value of fibrinogen for active group was 3.60, with a specificity of 89.1% and sensitivity of 58.3%. Binary logistic regression analysis showed fibrinogen (odds ratio = 2.71, 95% confidence interval: 1.28-5.74, p = 0.011) was a predictor for gout disease activity. CONCLUSION: Fibrinogen was increased in active gout group. Fibrinogen can serve as a reliable inflammatory marker for monitoring inflammatory response and disease activity in gout patients.


Assuntos
Fibrinogênio , Gota , Biomarcadores , Produtos de Degradação da Fibrina e do Fibrinogênio , Fibrinogênio/análise , Gota/diagnóstico , Humanos , Curva ROC , Estudos Retrospectivos
20.
Phys Chem Chem Phys ; 22(34): 19202-19212, 2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32812593

RESUMO

Large Schottky barrier at the electric contact interface drastically hinders the performance of two-dimensional (2D) semiconductor devices, because of which it is crucial to develop better methods to achieve the ohmic contact. Recently, a new field effect transistor (FET) device was constructed by the popular 2D channel material MoS2 and an electrode material borophene was detected theoretically, but the large Schottky barrier still existed. Hence, we used surface functional groups modification on the borophene surface to regulate this Schottky barrier, based on ab initio electronic structure calculations and quantum transport simulations. Our study shows that this method makes it possible to obtain tunable metal work functions in a wide range, and the ohmic contact can still be realized. Although van der Waals (vdW) contacts were observed at all the interfaces between the 2D borophene-based metals and the monolayer MoS2, the Fermi level pinning (FLP) effect was still obvious, and existed in our proposed system with the ohmic contact. Moreover, we also discuss the origin of the FLP with varying degrees. It was found that the interface dipole and metal-induced gap states (MIGS) would be responsible for the FLP of vertical and lateral directions, respectively. More precisely, we find that the size of MIGS is dependent on the relative orientation between the functional group and metal-MoS2 interface. This work not only suggests that surface functional group modification is effective in forming ohmic contact with MoS2, but also holds some implication in the fundamental research on metal-semiconductor contacts with the vdW type.

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