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1.
Bioorg Med Chem ; 70: 116937, 2022 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-35863236

RESUMEN

Fms-like tyrosine kinase 3 (FLT3) mutation has been strongly associated with increased risk of relapse, and the irreversible covalent FLT3 inhibitors had the potential to overcome the drug-resistance. In this study, a series of simplified 4-(4-aminophenyl)-6-methylisoxazolo[3,4-b] pyridin-3-amine derivatives containing two types of Michael acceptors (vinyl sulfonamide, acrylamide) were conveniently synthesized to target FLT3 and its internal tandem duplications (ITD) mutants irreversibly. The kinase inhibitory activities showed that compound C14 displayed potent inhibition activities against FLT3 (IC50 = 256 nM) and FLT3-ITD by 73 % and 25.34 % respectively, at the concentration of 1 µM. The antitumor activities indicated that C14 had strong inhibitory activity against the human acute myeloid leukemia (AML) cell lines MOLM-13 (IC50 = 507 nM) harboring FLT3-ITD mutant, as well as MV4-11 (IC50 = 325 nM) bearing FLT3-ITD mutation. The biochemical analyses showed that these effects were related to the ability of C14 to inhibit FLT3 signal pathways, and C14 could induce apoptosis in MV4-11 cell as demonstrated by flow cytometry. Fortunately, C14 showed very weak potency against FLT3-independent human cervical cancer cell line HL-60 (IC50 > 10 µM), indicating that it might have no off-target toxic effects. In light of these data, compound C14 represents a novel covalent FLT3 kinase inhibitor for targeted therapy of AML.


Asunto(s)
Antineoplásicos , Leucemia Mieloide Aguda , Aminas/farmacología , Antineoplásicos/química , Apoptosis , Línea Celular Tumoral , Humanos , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/patología , Mutación , Inhibidores de Proteínas Quinasas/química , Tirosina Quinasa 3 Similar a fms
2.
J Hazard Mater ; 435: 128981, 2022 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-35523090

RESUMEN

Environmental risk of multi-year polythene film mulching (PM) was evaluated and investigated. The location observation following 19-year (2000-2018) PM in irrigated region indicated that the cumulative accumulation of soil microplastics was as high as 2900 ± 19.5 n kg-1. Microplastic accumulation was tightly associated with soil plasticizer concentration (Pearson's r = 0.728, p <0.05), and the concentration of dominant phthalic acid esters (PAEs) was up to 117.5-705 µg kg-1. As such, we conducted organic mulching substitute experiment (2019-2020) with non-mulching (CK), maize straw mulching (SM), living clover mulching (CM), PM, PM+SM and PM+CM respectively. The data showed that organic mulching (SM, CM) achieved similar productivity benefit as PM-involved treatments (p > 0.05). Critically, total concentration of PAEs decreased by 6.43% in SM relative to CK, and by 9.61% in PM+SM relative to PM respectively. High throughput sequencing indicated that the proportions of predominant bacteria and fungi were totally lower in PM than those of organic mulching, particularly Sphingomonadaceae and Stachybotryaceae. KEGG analyses indicated that organic mulching promoted the metabolisms of polycyclic aromatic hydrocarbons, benzoic acid (probability>75%) and heterologous organism metabolism (p<0.001), due to improved microbial community assembly. Therefore, organic mulching efficiently accelerated microbial mineralization of PM pollutants, and may act as a green solution to displace PM.


Asunto(s)
Agricultura , Plásticos , China , Polietileno/análisis , Suelo , Agua/análisis , Zea mays
3.
Biol Trace Elem Res ; 2022 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-35397105

RESUMEN

Selenium (Se) is a vital trace element in the regulation of inflammation and antioxidant reactions in both animals and humans. Se deficiency is rapidly affecting lung function. The present study investigated the molecular mechanism of Se deficiency aggravates reactive oxygen species (ROS)-induced inflammation, leading to fibrosis in lung. Mice fed with different concentrations of Se to establish the model. In the Se-deficient group, the ROS and malondialdehyde (MDA) was increased, and the activities of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), total antioxidant capacity (T-AOC), and catalase (CAT) reduced. The histopathological observation showed that Se deficiency lead to lung texture damage with varying degrees of degeneration, necrosis, shedding of some alveolar epithelial cells, and inflammatory cell infiltration. Immunohistochemistry showed that the expression of α-smooth muscle actin (α-SMA) increased. The fibrosis index was verified with Sirius red staining. The ELISA and qPCR results showed that the inflammatory cytokines (TNF-α and IL-1ß) and ECM (collagen I, collagen IV, fibronectin, and laminin) were increased with ROS increasing, which was induced by Se deficiency. The results displayed that oxidative stress with Se deficiency led to an increase in tissue inhibitors of metalloproteinase (TIMPs), but a decrease in matrix metalloproteinases (MMPs). All the results indicated that Se deficiency induced excessive ROS accumulation to generate inflammation, which disrupted ECM homeostasis and aggravated fibrosis in the lung.

4.
Int J Colorectal Dis ; 37(4): 949-956, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35315507

RESUMEN

PURPOSE: We aim to identify the risk factors of PPOI in patients with CD and create a nomogram for prediction of PPOI for CD. METHODS: Data on 462 patients who underwent partial intestinal resection for CD in Jin-ling Hospital between January 2019 and June 2021 were retrospectively collected. Univariate and multivariate analyses were performed to determine the risk factors for PPOI and we used the risk factors to create a nomogram. Then we used the Bootstrap-Concordance index and calibration diagrams to evaluate the performance of the Nomogram. Decision curve analysis was performed to evaluate clinical practicability of the model. RESULTS: The incidence of PPOI was 27.7% (n of N). Course of CD ≥ 10 years, operation time ≥ 154 min, the lowest mean arterial pressure ≤ 76.2 mmHg, in-out balance per body weight ≥ 22.90 ml/kg, post-op day 1 infusion ≥ 2847 ml, post-op lowest K+ ≤ 3.75 mmol/L, and post-op day 1 procalcitonin ≥ 2.445 ng/ml were identified as the independent risk factors of PPOI in patients with CD. The nomogram we created by these risk factors presented with good discriminative ability (concordance index 0.723) and was moderately calibrated (bootstrapped concordance index 0.704). The results of decision curve analysis showed that the nomogram was clinically effective within probability thresholds in the 8 to 66% range. CONCLUSION: The nomogram we developed is helpful to evaluate the risk of developing PPOI after partial intestinal resection for CD. Clinicians can take more necessary measures to prevent PPOI in CD's patients or at least minimize the incidence.


Asunto(s)
Enfermedad de Crohn , Ileus , Enfermedad de Crohn/complicaciones , Enfermedad de Crohn/cirugía , Humanos , Ileus/epidemiología , Ileus/etiología , Nomogramas , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos , Factores de Riesgo
5.
J Sci Food Agric ; 102(6): 2553-2562, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34687471

RESUMEN

BACKGROUND: ß-N-oxalyl-l-α,ß-diaminopropionic acid (ß-ODAP) is a physiological indicator in response to drying soil. However, how abscisic acid (ABA) modulates ß-ODAP accumulation and its related agronomic characteristics in drought stressed grass pea (Lathyrus sativus L.) continue to be unclear. The present study aimed to evaluate the effects of ABA addition on drought tolerance, agronomic characteristics and ß-ODAP content in grass pea under drought stress. RESULTS: Exogenous ABA significantly promoted ABA levels by 19.3% and 18.3% under moderate and severe drought stress, respectively, compared to CK (without ABA, used as control check treatment). ABA addition activated earlier trigger of non-hydraulic root-sourced signal at 69.1% field capacity (FC) (65.5% FC in CK) and accordingly prolonged its operation period to 45.6% FC (49.0% FC in CK). This phenomenon was mechanically associated with the physiological mediation of ABA, where its addition significantly promoted the activities of leaf superoxide dismutase, catalase and peroxidase enzymes and the biosynthesis of leaf proline, simultaneously lowering the accumulation of malondialdehyde and hydrogen peroxide under moderate and severe stresses. Interestingly, ABA application significantly increased seed ß-ODAP content by 21.7% and 21.3% under moderate and severe drought stress, but did not change leaf ß-ODAP content. Furthermore, ABA application produced similar shoot biomass and grain yield as control groups. CONCLUSION: Exogenous ABA improved the drought adaptability of grass pea and promoted the synthesis of ß-ODAP in seeds but not in leaves. Our findings provide novel insights into the agronomic role of ABA in relation to ß-ODAP enrichment in grass pea subjected to drought stress. © 2021 Society of Chemical Industry.


Asunto(s)
Lathyrus , Ácido Abscísico , Aclimatación , Aminoácidos Diaminos , Sequías , Lathyrus/química , Guisantes , beta-Alanina/análogos & derivados
6.
J Hazard Mater ; 416: 125954, 2021 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-34492872

RESUMEN

Biodegradable (Bio) plastic films are widely viewed as promising alternative products of low-density polyethylene (LDPE) films to minimize plastic debris accumulation and pollution in agroecosystems. Yet, this speculation indeed lacks of sufficient evidences. We conducted a landfill investigation on the aging characteristics of Bio and LDPE plastic films in maize field, and the effects on soil aggregate composition and carbon & nitrogen stocks. The degradation rate of Bio film was up to 41.1% while that of LDPE film was zero. Scanning electron microscope (SEM) showed that the crack formation of Bio film had a pronounced domino effect, and FTIR showed that old Bio film displayed an extra wide peak threshold ranging from 3000 to 3500 cm-1. Particularly, the abundance of microplastics was elevated with the increased plastic residues, and the increment mostly resulted from Bio residues. Critically, plastic residues significantly lowered the soil macro-aggregates (>0.25 mm) proportion, while increasing that of micro-aggregates (0.1-0.25 mm) in LDPE, and silt/clay fraction (<0.1 mm) in Bio respectively. They significantly promoted total nitrogen content of the aggregates with the same size, but decreased the organic carbon content, dramatically lowering the C/N. Therefore, we first identified the fate of plastic film residues in agroecosystems and revealed the serious deficiencies of Bio plastic film.


Asunto(s)
Plásticos Biodegradables , Suelo , Agricultura , Carbono , Ecosistema , Nitrógeno , Plásticos
7.
Zhongguo Zhong Yao Za Zhi ; 46(12): 3116-3122, 2021 Jun.
Artículo en Chino | MEDLINE | ID: mdl-34467703

RESUMEN

Screening suitable reference genes is the premise of quantitative Real-time PCR(qRT-PCR)for gene expression analysis. To provide stable reference genes for expression analysis of genes in Aconitum vilmorinianum, this study selected 19 candidate re-ference genes(ACT1, ACT2, ACT3, aTUB1, aTUB2, bTUB, 18S rRNA, UBQ, eIF2, eIF3, eIF4, eIF5, CYP, GAPDH1, GAPDH2, PP2A1, PP2A2, ACP, and EF1α) based on the transcriptome data of A. vilmorinianum. qRT-PCR was conducted to profile the expression of these genes in the root, stem, leaf, and flower of A. vilmorinianum. The Ct values showed that 18S rRNA with high expression level and GAPDH2 with large expression difference among organs were not suitable as the reference genes. NormFinder and geNorm showed similar results of the expression stability of the other candidate reference genes and demonstrated PP2A1, EF1α, and CYP as the highly stable ones. However, BestKeeper suggested EF1α, ACT3, and PP2A1 as the top stable genes. In view of the different results from different softwares, the geometric mean method was employed to analyze the expression stability of the candidate re-ference genes, the results of which indicated that PP2A1, EF1α, and ACT3 were the most stable. Based on the comprehensive analysis results of geNorm, NormFinder, BestKeeper, and geometric mean method, PP2A1 and EF1α presented the most stable expression in different organs of A. vilmorinianum. PP2A1 and EF1α were the superior reference genes for gene expression profiling in different organs of A. vilmorinianum.


Asunto(s)
Aconitum , Perfilación de la Expresión Génica , Genes de Plantas/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Estándares de Referencia , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
8.
J Phys Chem B ; 125(21): 5630-5635, 2021 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-34008980

RESUMEN

The kinematic time and maximum spreading time for the impact of nanodroplets of different types of fluids on solid surfaces with different wettability are investigated. It shows that the capillary regime still exits for the nanodroplet impact, even if viscous dissipation increases significantly when the droplet size reduces to the nanoscale. By taking into account the influence of liquid types and surface wettability, we first obtain scaling laws of the maximum spreading time for the capillary and viscous regimes. We further propose a universal scaling law by interpolating the scaling laws in the two asymptotic regimes. The universal scaling law is in excellent agreement with molecular dynamics simulations for various liquids and surface wettability.

9.
J Hazard Mater ; 414: 125521, 2021 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-34030405

RESUMEN

Intensive use of low-density polyethylene (LDPE) plastic films in agro-ecosystems has raised considerable concerns due to the increasing film residues in soils. It is unclear how the increased film residues affect soil properties and crop productivity and whether biodegradable (Bio) film can substitute LDPE. To address the issue, we designed a landfill experiment with different addition levels of plastic residue into soils of maize (Zea mays L.) field from 2018 to 2019. Six treatments were arranged as PMT1-T3/BioT1-T3, representing the low, medium, and high-level application of LDPE / Bio film fragments, with no residual film, applied as CK. Results show that, soil bulk density was significantly increased from 1.19 to 1.31 g/cm3 regardless of residue types. In contrast, soil porosity was lowered from 58.03% in CK to 57.36% in Bio and 56.12% in LDPE significantly (P < 0.05). Increased residues improved soil nitrogen level and lowered the C/N ratio significantly. Also, it decreased microbial biomass C and N levels but with no change in C/N (P < 0.05). Maize yield and WUE decreased, while soil water storage increased significantly. LDPE residues affected soil properties and productivity partly lower than Bio ones did, but the negative effects of them were similar in the maize field.


Asunto(s)
Ecosistema , Suelo , Agricultura , China , Plásticos , Zea mays
10.
Proc Natl Acad Sci U S A ; 118(14)2021 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-33790019

RESUMEN

Nonlinear mechanics of solids is an exciting field that encompasses both beautiful mathematics, such as the emergence of instabilities and the formation of complex patterns, as well as multiple applications. Two-dimensional crystals and van der Waals (vdW) heterostructures allow revisiting this field on the atomic level, allowing much finer control over the parameters and offering atomistic interpretation of experimental observations. In this work, we consider the formation of instabilities consisting of radially oriented wrinkles around mono- and few-layer "bubbles" in two-dimensional vdW heterostructures. Interestingly, the shape and wavelength of the wrinkles depend not only on the thickness of the two-dimensional crystal forming the bubble, but also on the atomistic structure of the interface between the bubble and the substrate, which can be controlled by their relative orientation. We argue that the periodic nature of these patterns emanates from an energetic balance between the resistance of the top membrane to bending, which favors large wavelength of wrinkles, and the membrane-substrate vdW attraction, which favors small wrinkle amplitude. Employing the classical "Winkler foundation" model of elasticity theory, we show that the number of radial wrinkles conveys a valuable relationship between the bending rigidity of the top membrane and the strength of the vdW interaction. Armed with this relationship, we use our data to demonstrate a nontrivial dependence of the bending rigidity on the number of layers in the top membrane, which shows two different regimes driven by slippage between the layers, and a high sensitivity of the vdW force to the alignment between the substrate and the membrane.

11.
Langmuir ; 37(13): 3929-3938, 2021 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-33760619

RESUMEN

Sweeping deposited particles is absolutely essential in order to maintain the excellent functionality of superhydrophobic surfaces. Many methods have been proposed to sweep microparticles deposited on tips of micro/nanostructures. However, how to sweep nanoparticles trapped in cavities of superhydrophobic surfaces has remained an outstanding issue. Here, we show that harnessing the reversible wetting transition provides a feasible way to sweep such nanoparticles. Using molecular dynamics simulations, we demonstrate that the electrically induced CB-W wetting transition makes liquid intrude into a groove and wet a trapped hydrophilic nanoparticle; however, once the electric field is removed, a spontaneous W-CB dewetting transition happens, and the extruded liquid transports the hydrophilic nanoparticle to the groove top, successfully picking up the trapped hydrophilic nanoparticle. We further find that the adhesion between the nanoparticle and groove bottom wall hinders the successful pickup, and picking up such a nanoparticle requires a stronger particle hydrophilicity. With the introduction of amphiphilic Janus particles into a liquid, we exhibit that the electrically induced reversible wetting transition can also successfully pick up a trapped hydrophobic nanoparticle. By means of calculations of the potential of mean force (PMF), we reveal pathways of both the CB-W wetting transition and the W-CB dewetting transition and hence answer why and how a hydrophilic or a hydrophobic nanoparticle is picked up successfully.

12.
Chin Med J (Engl) ; 134(3): 292-301, 2021 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-33470655

RESUMEN

BACKGROUND: Generic drugs are bioequivalent to their brand-name counterparts; however, concerns still exist regarding the effectiveness and safety of generic drugs because of small sample sizes and short follow-up time in most studies. The purpose of this study was to evaluate the long-term antihypertensive efficacy, cost-effectiveness and cardiovascular outcomes of generic drugs compared with brand-name drugs. METHODS: In a multicenter, community-based study including 7955 hypertensive patients who were prospectively followed up for an average of 2.5 years, we used the propensity-score-matching method to match the patients using brand-name drugs to those using generic drugs in a ratio of 1:2, 2176 patients using brand-name drugs and 4352 patients using generic drugs. RESULTS: There were no significant differences between generic drugs and brand-name drugs in blood pressure (BP)-lowering efficacy, BP control rate, and cardiovascular outcomes including coronary heart disease and stroke. The adjusted mean (95% confidence interval [CI]) of systolic BP (SBP)-lowering was -7.9 mmHg (95% CI, -9.9 to -5.9) in the brand-name drug group and -7.1 mmHg (95% CI, -9.1 to -5.1) in the generic drug group after adjusting for age, sex, body mass index, number of antihypertensive drugs and traditionally cardiovascular risk factors. Among patients aged <60 years, brand-name drugs had a higher BP control rate (47% vs. 41%; P = 0.02) and a greater effect in lowering SBP compared with generic drugs, with the between-group difference of 1.5 mmHg (95% CI, 0.2-2.8; P = 0.03). BP control rate was higher in male patients using brand-name drugs compared with those using generic drugs (46% vs. 40%; P = 0.01). Generic drugs treatment yielded an average annual incremental cost-effectiveness ratio of $315.4 per patient per mmHg decrease in SBP compared with brand-name drugs treatment. CONCLUSIONS: Our data suggested that generic drugs are suitable and cost-effective in improving hypertension management and facilitating public health benefits, especially in low- and middle-income areas.


Asunto(s)
Antihipertensivos , Medicamentos Genéricos , Anciano , Antihipertensivos/uso terapéutico , Presión Sanguínea , China , Medicamentos Genéricos/uso terapéutico , Humanos , Masculino , Estudios Prospectivos
13.
Ultramicroscopy ; 219: 113020, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33022532

RESUMEN

The convergent beam electron diffraction (CBED) patterns of twisted bilayer samples exhibit interference patterns in their CBED spots. Such interference patterns can be treated as off-axis holograms and the phase of the scattered waves, meaning the interlayer distance can be reconstructed. A detailed protocol of the reconstruction procedure is provided in this study. In addition, we derive an exact formula for reconstructing the interlayer distance from the recovered phase distribution, which takes into account the different chemical compositions of the individual monolayers. It is shown that one interference fringe in a CBED spot is sufficient to reconstruct the distance between the layers, which can be practical for imaging samples with a relatively small twist angle or when probing small sample regions. The quality of the reconstructed interlayer distance is studied as a function of the twist angle. At smaller twist angles, the reconstructed interlayer distance distribution is more precise and artefact free. At larger twist angles, artefacts due to the moiré structure appear in the reconstruction. A method for the reconstruction of the average interlayer distance is presented. As for resolution, the interlayer distance can be reconstructed by the holographic approach at an accuracy of ±0.5 Å, which is a few hundred times better than the intrinsic z-resolution of diffraction limited resolution, as expressed through the spread of the measured k-values. Moreover, we show that holographic CBED imaging can detect variations as small as 0.1 Å in the interlayer distance, though the quantitative reconstruction of such variations suffers from large errors.

14.
Huan Jing Ke Xue ; 41(9): 3924-3931, 2020 Sep 08.
Artículo en Chino | MEDLINE | ID: mdl-33124271

RESUMEN

The spectral characteristics and sources of water-soluble organic compounds (WSOC) in PM2.5 in winter were studied by using UV-vis absorption spectroscopy, three-dimensional fluorescence spectroscopy, parallel factor analysis, and backward trajectory model. The results showed that the concentration of WSOC in PM2.5 was 4.66-14.75 µg ·m-3. The values of E2/E3, E3/E4, S275-295, SUVA254, AAE, and MAE365 of WSOC were, respectively, in the range of 2.85-4.32, 2.21-3.56, 0.0099-0.0127 nm-1, 2.35-3.89 m2 ·g-1, 2.66-4.60, and 1.51-2.60 m2 ·g-1. The E2/E3, E3/E4, S275-295, and AAE values of WSOC at the sampling site in the southern suburb of Xi'an, China (Xi'an University of Architecture and Technology) were higher than those at the sampling site in the northern suburb (sports park), while the values of SUVA254 and MAE365 were lower. There were four fluorescent components in WSOC identified by the EEMs-PARAFAC model: C1 and C2 were fulvic acid-like and protein-like, respectively, and C3 and C4 were humus-like components. The fluorescence intensities and the sum of the fluorescent components were positively correlated with the concentrations of PM2.5, OC, WSOC, and A254 value (P<0.01). The fluorescence index (FI), biological source index (BIX), and humic index (HIX) values of WSOC were 1.75-2.12, 1.14-1.46, and 1.18-2.06, respectively. During the monitoring period, the air mass transmission trajectory was dominated by the local southwest of short-distance transmission, and its trajectory accounted for more than 50%. The pollutant emissions from Xinjiang, Inner Mongolia, and Gansu also made significant contributions to the air pollution levels in Xi'an in winter. There was a small difference in the carbon component content of PM2.5 in the northern and southern suburbs of Xi'an. The molecular weight, humification degree, and light absorption capacity of WSOC at the southern suburb sampling site were lower than those in the northern suburb where the wavelength dependence of light absorption intensity was relatively stronger. The WSOC mainly originated from biological sources or both from biological and terrestrial sources. Local transmission had the most significant contribution to PM2.5 and WSOC in winter.


Asunto(s)
Contaminantes Atmosféricos , Material Particulado , Contaminantes Atmosféricos/análisis , China , Monitoreo del Ambiente , Material Particulado/análisis , Estaciones del Año , Agua
15.
Langmuir ; 36(31): 9306-9316, 2020 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-32697096

RESUMEN

Using molecular dynamics (MD) simulations, we investigate impact behaviors of water nanodroplets on hydrophilic to hydrophobic surfaces with static contact angles ranging from 21 to 148° in a wide Weber number range of 15-90, aiming to understand how the surface wettability influences the maximum spreading factor of nanodroplets. We show that the existing macroscale and nanoscale models cannot capture the influence of surface wettability on the maximum spreading factor. We demonstrate that the failure is attributed to the rough estimation of the spreading velocity during the spreading stage, which is assumed to be a constant value in these models. We show that the spreading velocity strongly depends on both the surface wettability and the Weber number. After scaling with the impact velocity, we obtain a universal function of the spreading velocity with respect to the static contact angle and the Weber number. We employ this function to modify the expression of viscous dissipation and develop a new model of the maximum spreading factor. We verify that the model is in excellent agreement with the MD simulations regardless of hydrophilic and hydrophobic surfaces, with the mean relative deviation ranging from 0.88 to 4.75%. We also provide evidence to support the fact that incorporating the influence of surface wettability by modifying viscous dissipation is more reasonable than by modifying surface energy for nanodroplet impact.

17.
Ultramicroscopy ; 212: 112976, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32217349

RESUMEN

Convergent beam electron diffraction is routinely applied for studying deformation and local strain in thick crystals by matching the crystal structure to the observed intensity distributions. Recently, it has been demonstrated that CBED can be applied for imaging two-dimensional (2D) crystals where a direct reconstruction is possible and three-dimensional crystal deformations at a nanometre resolution can be retrieved. Here, we demonstrate that second-order effects allow for further information to be obtained regarding stacking arrangements between the crystals. Such effects are especially pronounced in samples consisting of multiple layers of 2D crystals. We show, using simulations and experiments, that twisted multilayer samples exhibit extra modulations of interference fringes in CBED patterns, i. e., a CBED moiré. A simple and robust method for the evaluation of the composition and the number of layers from a single-shot CBED pattern is demonstrated.

18.
J Toxicol Sci ; 45(3): 163-175, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32147639

RESUMEN

The benefits and adverse effects of immunosuppressive drugs (ISDs) in patients with paraquat (PQ) poisoning have not been thoroughly assessed. This meta-analysis study aims to evaluate the effect of ISDs in patients with moderate to severe PQ poisoning. We searched PubMed, Embase, Cochrane Library, Ovid Medline, CNKI and Wanfang Data from inception to January 2019. The Mantel-Haenszel method with a random-effects model was used to calculate the pooled relative risks (RRs) and 95% Confidence Intervals (CIs) as described by DerSimonian and Laird. An L'Abbé plot was drawn to explore the relationship between the degree of poisoning and mortality. Four randomized controlled trials, two prospective and seven retrospective studies were identified. ISDs were significantly associated with reduced mortality (RR 0.76; 95% CI, 0.58-0.99) and the incidence rate of multiple-organ dysfunction syndrome (MODS) (RR 0.63; 95% CI, 0.48-0.83) in patients with moderate to severe PQ poisoning. They were not associated with an increased incidence rate of hepatitis and reduced incidence rate of acute renal failure and hypoxia. The L'Abbé plot results showed a slight increase in mortality rate in the ISD group with increased mortality in the placebo group. This indicates a possible advantage of ISDs in most of the patients with severe PQ poisoning. These findings suggest that ISDs may reduce the mortality and incidence rate of MODS in moderate to severe PQ poisoning patients, and severe PQ poisoning patients might benefit more from ISDs.


Asunto(s)
Inmunosupresores/administración & dosificación , Paraquat/envenenamiento , Intoxicación/tratamiento farmacológico , Intoxicación/mortalidad , Humanos , Mortalidad , Insuficiencia Multiorgánica/inducido químicamente , Insuficiencia Multiorgánica/prevención & control , Índice de Severidad de la Enfermedad
19.
J Comput Chem ; 41(13): 1252-1260, 2020 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-32045021

RESUMEN

The popular method of calculating the noncovalent interaction energies at the coupled-cluster single-, double-, and perturbative triple-excitations [CCSD(T)] theory level in the complete basis set (CBS) limit was to add a CCSD(T) correction term to the CBS second-order Møller-Plesset perturbation theory (MP2). The CCSD(T) correction term is the difference between the CCSD(T) and MP2 interaction energies evaluated in a medium basis set. However, the CCSD(T) calculations with the medium basis sets are still very expensive for systems with more than 30 atoms. Comparatively, the domain-based local pair natural orbital coupled-cluster method [DLPNO-CCSD(T)] can be applied to large systems with over 1,000 atoms. Considering both the computational accuracy and efficiency, in this work, we propose a new scheme to calculate the CCSD(T)/CBS interaction energies. In this scheme, the MP2/CBS term keeps intact and the CCSD(T) correction term is replaced by a DLPNO-CCSD(T) correction term which is the difference between the DLPNO-CCSD(T) and DLPNO-MP2 interaction energies evaluated in a medium basis set. The interaction energies of the noncovalent systems in the S22, HSG, HBC6, NBC10, and S66 databases were recalculated employing this new scheme. The consistent and tight settings of the truncation parameters for DLPNO-CCSD(T) and DLPNO-MP2 in this noncanonical CCSD(T)/CBS calculations lead to the maximum absolute deviation and root-mean-square deviation from the canonical CCSD(T)/CBS interaction energies of less than or equal to 0.28 kcal/mol and 0.09 kcal/mol, respectively. The high accuracy and low cost of this new computational scheme make it an excellent candidate for the study of large noncovalent systems.

20.
Adv Mater ; 32(1): e1905504, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31736228

RESUMEN

2D hexagonal boron nitride (hBN) is a wide-bandgap van der Waals crystal with a unique combination of properties, including exceptional strength, large oxidation resistance at high temperatures, and optical functionalities. Furthermore, in recent years hBN crystals have become the material of choice for encapsulating other 2D crystals in a variety of technological applications, from optoelectronic and tunneling devices to composites. Monolayer hBN, which has no center of symmetry, is predicted to exhibit piezoelectric properties, yet experimental evidence is lacking. Here, by using electrostatic force microscopy, this effect is observed as a strain-induced change in the local electric field around bubbles and creases, in agreement with theoretical calculations. No piezoelectricity is found in bilayer and bulk hBN, where the center of symmetry is restored. These results add piezoelectricity to the known properties of monolayer hBN, which makes it a desirable candidate for novel electromechanical and stretchable optoelectronic devices, and pave a way to control the local electric field and carrier concentration in van der Waals heterostructures via strain. The experimental approach used here also shows a way to investigate the piezoelectric properties of other materials on the nanoscale by using electrostatic scanning probe techniques.

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