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2.
J Integr Plant Biol ; 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33605510

RESUMO

Mitogen-activated protein kinases (MPKs) play essential roles in guard cell signaling, but whether MPK cascades participate in guard cell ethylene signaling and interact with hydrogen peroxide (H2 O2 ), nitric oxide (NO), and ethylene-signaling components remain unclear. Here, we report that ethylene activated MPK3 and MPK6 in the leaves of wild-type Arabidopsis thaliana as well as ethylene insensitive2 (ein2), ein3, nitrate reductase1 (nia1), and nia2 mutants, but this effect was impaired in ethylene response1 (etr1), NADPH oxidase AtrbohF, mpk kinase1 (mkk1) and mkk3 mutants. By contrast, the constitutive triple response1 (ctr1) mutant had constitutively active MPK3 and MPK6. Yeast two-hybrid, bimolecular fluorescence complementation, and pull-down assays indicated that MPK3 and MPK6 physically interacted with MKK1, MKK3, and the C-terminal region of EIN2 (EIN2 CEND). mkk1, mkk3, mpk3, and mpk6 mutants had typical levels of ethylene-induced H2 O2 generation but impaired ethylene-induced EIN2 CEND cleavage and nuclear translocation, EIN3 protein accumulation, NO production in guard cells, and stomatal closure. These results show that the MKK1/3-MPK3/6 cascade mediates ethylene-induced stomatal closure by functioning downstream of ETR1, CTR1, and H2 O2 to interact with EIN2, thereby promoting EIN3 accumulation and EIN3-dependent NO production in guard cells. This article is protected by copyright. All rights reserved.

3.
Soft Matter ; 2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33527960

RESUMO

Abnormal fast dehydration and rehydration of light- and thermo-dual-responsive copolymer films of poly(oligo(ethylene glycol) methyl ether methacrylate-co-6-(4-phenylazophenoxy)hexyl acrylate), abbreviated as P(OEGMA300-co-PAHA), are triggered by UV radiation. Both rapid kinetic processes are probed by in situ neutron reflectivity (NR). The transition temperatures (TTs) of P(OEGMA300-co-PAHA) are 53.0 (ambient conditions) and 52.5 °C (UV radiation, λ = 365 nm). Thin P(OEGMA300-co-PAHA) films show a random distribution of OEGMA300 and PAHA segments. They swell in a D2O vapor atmosphere at 23 °C (below TT) to a swelling ratio d/das-prep of 1.61 ± 0.01 and exhibit a D2O volume fraction φ(D2O) of 39.3 ± 0.5%. After being exposed to UV radiation for only 60 s, d/das-prep and φ(D2O) significantly decrease to 1.00 ± 0.01 and 13.4 ± 0.5%, respectively. Although the UV-induced trans-cis isomerization of the azobenzene in PAHA induces increased hydrophilicity, the configuration change causes a breaking of the intermolecular hydrogen bonds between OEGMA300 and D2O molecules and unexpected film shrinkage. As compared to thermal stimulus-induced dehydration, the present dehydration rate is 100 times faster. Removal of the UV radiation causes immediate rehydration. After 200 s, d/das-prep and φ(D2O) recover to their hydrated states, which is also 30 times faster than the initial hydration. At 60 °C (above TT), thin P(OEGMA300-co-PAHA) films switch to their collapsed state and are insensitive to UV radiation. Thus, the UV-induced fast dehydration and rehydration depend on the existence of hydrogen bonds.

4.
Nanoscale ; 2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33475113

RESUMO

Sulfur quantum dots (SQDs) are a new kind of functional nanomaterial, but several challenges still exist in relation to their synthesis and application, such as low-yield and time-consuming synthetic methods, low photoluminescence quantum yields (PLQYs), and the non-selectivity of their detection mechanisms. Herein, we report the drastic enhancement of the fluorescence performance of water-soluble SQDs via the one-pot synthesis of size-focusing QDs using ultrasound microwave radiation. The synthetic period has been greatly shortened to 2 h via the present process. Notably, the proposed SQDs exhibit a highly stable emission wavelength with a record high PLQY of 58.6%. The mechanistic study indicates that size-focusing is a key factor relating to the proposed high-performance SQDs. As they also have robust stability, the proposed SQDs show a wide range of potential applications. Inspired by the characteristic properties of the SQDs and specific analytes, a simple SQD-based fluorescence sensing platform, via a redox-reaction-mediated mechanism, has been successfully developed for the rapid and selective detection of Ce(iv). In addition, this system has been effectively applied to some Ce(iv)-related biological assays, such as ascorbic acid (AA) analysis. This work is an important breakthrough in the SQD field, opening up avenues for solving the challenging problems relating to SQD-based probes, enriching the fundamental understanding of them, and greatly extending their applications, especially in biomedicine.

5.
J Clin Lab Anal ; : e23688, 2021 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-33389756

RESUMO

BACKGROUND: Distinct populations differ in LVH prevalence and impaired LV geometry. Currently, the prevalence of and risk factors for LV geometric patterns in Chinese hypertensives administered irbesartan have not been specifically addressed in large studies. METHODS: Totally 10,883 patients (6623 men and 4260 women) completed the survey, including 1181 hypertensives administered irbesartan (488 males and 693 females) that were finally enrolled. Based on LVMI and RWT derived from comprehensive echocardiography, the LV geometric patterns of irbesartan-treated hypertensive individuals were classified into four types, including the normal, concentric remodeling, and concentric and eccentric hypertrophy groups. Logistic regression analysis was applied in males and females, respectively, for determining odds ratios (ORs) and 95% confidence intervals (CIs) for various potential risk factors for abnormal LV geometrical patterns in irbesartan-treated hypertensives. RESULTS: The clinical and echocardiographic data differed significantly between males and females. The prevalence rates of concentric remodeling, concentric hypertrophy, and eccentric hypertrophy were 36.3%, 15.4%, and 6.1% in males, respectively, and 23.5%, 20.3%, and 23.8% in females, accordingly. Gender, daily dose of irbesartan, BMI, SBP, WtHR, and neck-circumference were significantly associated with LV geometric patterns. After adjustment for confounding factors, risk factors for LVH and impaired LV geometry included SBP, WtHR in males, and MAU-Cr and WtHR in females. CONCLUSIONS: LVH and impaired LV geometric patterns are more prevalent in females (67.7%) compared with that in males (57.8%) among hypertensives upon irbesartan administration. For such population, risk factors beyond elevated blood pressure may be involved in the progression of LVH and impaired LV geometric patterns in both genders.

6.
Exp Cell Res ; 400(2): 112505, 2021 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33516666

RESUMO

Inflammation and alveolar bone destruction constitute the main pathological process of periodontitis. However, the molecular mechanisms of bone destruction under the inflammation environment remain unclear. This study aims to explore the role of Ephrin-B2/EphB4 signaling in osteogenic differentiation under the inflammation environment. Mouse pre-osteoblasts MC3T3-E1 were pretreated with lipopolysaccharide of Porphyromonas gingivalis (Pg-LPS). The Ephrin-B2/EphB4 signaling was activated, and the osteogenic differentiation of cells was examined. The results showed that activation of Ephrin-B2/EphB4 signaling promoted the expression levels of osteogenic differentiation-related genes, and also relieved the inhibitory effect of Pg-LPS on osteogenesis. Noticeably, the effect of Ephrin-B2/EphB4 signaling might be related to the mitogen-activated protein kinase (MAPK) pathway. While applying Ephrin-B2-Fc and EphB4-Fc to periodontitis mice, we observed the reduction of alveolar crest destruction. The current study revealed the possible role of Ephrin-B2/EphB4 signaling in reducing bone destruction in periodontitis and suggested its potential values for further research.

7.
Hum Brain Mapp ; 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33283954

RESUMO

Until now, dynamic functional connectivity (dFC) based on functional magnetic resonance imaging is typically estimated on a set of predefined regions of interest (ROIs) derived from an anatomical or static functional atlas which follows an implicit assumption of functional homogeneity within ROIs underlying temporal fluctuation of functional coupling, potentially leading to biases or underestimation of brain network dynamics. Here, we presented a novel computational method based on dynamic functional connectivity degree (dFCD) to derive meaningful brain parcellations that can capture functional homogeneous regions in temporal variance of functional connectivity. Several spatially distributed but functionally meaningful areas that are well consistent with known intrinsic connectivity networks were identified through independent component analysis (ICA) of time-varying dFCD maps. Furthermore, a systematical comparison with commonly used brain atlases, including the Anatomical Automatic Labeling template, static ICA-driven parcellation and random parcellation, demonstrated that the ROI-definition strategy based on the proposed dFC-driven parcellation could better capture the interindividual variability in dFC and predict observed individual cognitive performance (e.g., fluid intelligence, cognitive flexibility, and sustained attention) based on chronnectome. Together, our findings shed new light on the functional organization of resting brains at the timescale of seconds and emphasized the significance of a dFC-driven and voxel-wise functional homogeneous parcellation for network dynamics analyses in neuroscience.

8.
Artigo em Inglês | MEDLINE | ID: mdl-33263977

RESUMO

The risk of extensive exposure of the human epidermis to solar ultraviolet radiation is significantly increased nowadays. It not only induces skin aging and solar erythema but also increases the possibility of skin cancer. Therefore, a simply prepared, highly sensitive, and optically readable device for monitoring the solar ultraviolet radiation is highly desired for the skin health management. Because of the photoinitiated polymerization triggered by graphene-carbon nitride (g-C3N4) under ultraviolet radiation, g-C3N4 is homogeneously distributed in the hybrid hydrogels containing N-isopropylacrymide (NIPAM), poly(ethylene glycol) methyl ether methacrylate (OEGMA300), and sodium alginate (SA). By further immersing the hybrid hydrogels into calcium chloride solution, hybrid alginate-Ca2+/P(NIPAM-co-OEGMA300)/g-C3N4 interpenetrating polymeric network (IPN) hydrogels are obtained. Due to the homogeneous distribution of g-C3N4 and the existence of thermoresponsive polymers, the hybrid IPN hydrogels present good adsorption capability and high degradation efficiency for methylene blue (MB) especially at high temperature under ultraviolet radiation. Based on this unique property, the bracelet monitoring skin health is prepared by simply immersing the hybrid IPN hydrogels into the MB solution and then wrapping it with PET foil. Because the immersion time for the top, middle, and bottom parts of the hybrid IPN hydrogels is gradually increased, their colors vary from light to dark blue. A longer time is required for the discoloration of the darker part under solar ultraviolet radiation. Thus, the bracelet can be used to conveniently monitor the dose of solar ultraviolet radiation by simply checking the discoloration in the bracelet under sunshine. Due to the facile preparation and low cost of the bracelet, it is a promising candidate for wearable devices for skin health management.

9.
World J Surg Oncol ; 18(1): 330, 2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33308220

RESUMO

BACKGROUND: This study aimed to evaluate the potential of induction chemotherapy as an indicator of the management of advanced hypopharyngeal carcinoma with cervical oesophageal invasion. METHODS: Sixty-eight patients admitted to our hospital between February 2003 and November 2016 with stage IVB hypopharyngeal carcinoma with cervical oesophageal invasion were retrospectively analysed. Patients were divided into two groups according to the treatment they selected following an explanation of the different treatments available. Patients in group A received induction chemotherapy and had (1) complete/partial remission following chemotherapy and radiotherapy/concurrent chemoradiotherapy or (2) stable disease following chemotherapy and surgery. Patients in group B underwent surgery followed by adjuvant radiotherapy/concurrent chemoradiotherapy. Survival analyses were performed using the Kaplan-Meier method, and differences between the groups were evaluated using the log-rank test. Laryngeal and oesophageal retention rates were compared using the cross-tabulation test. RESULTS: The 3- and 5-year overall survival rates were 22.86% and 11.43% in group A and 24.25% and 6.06% in group B, respectively (all P > 0.05). The laryngeal and oesophageal retention rates were 40.0% and 74.3% in group A and 0.0% and 27.3% in group B, respectively (all P < 0.01). There was no statistically significant difference in the incidence of post-operative complications between the two groups (group A 8.6%, group B 12.1%; P > 0.05). CONCLUSIONS: Induction chemotherapy may be an appropriate first choice to ensure laryngeal and oesophageal preservation in the individualised treatment of advanced hypopharyngeal carcinoma with cervical oesophageal invasion.

10.
Zootaxa ; 4881(1): zootaxa.4881.1.7, 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33311132

RESUMO

Fifteen parasitoids of Massicus raddei (Blessig Solsky) (Coleoptera, Cerambycidae) are revised. The host is a serious pest of Quercus liaotungensis Koidz. and Q. mongolica Fisch. ex Ledeb. in NE China. All the parasitoids were reared from larvae of M. raddei. Pseudocyanopterus gen. nov. raddeivorus sp. nov., a new braconid wasp is described, and Cyanopterus tricolor (Ivanov) and Eubazus (E.) pallipes are new records for the Chinese fauna. An identification key to the parasitoids of M. raddei in China is provided. Detailed photographs of the parasitoids are provided.


Assuntos
Besouros , Quercus , Vespas , Animais , China , Larva
11.
J Org Chem ; 2020 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-33378188

RESUMO

In the presence of the chiral Pd(0)/ligand complex, vinyl benzoxazinanones underwent the [4+2] cycloaddition with alkylidene pyrazolones smoothly and delivered spiropyrazolones in reasonable yields, diastereoselectivities, and eneantioselectivities (up to >99% yield, >99:1 dr and 99% ee). The absolute configuration of the obtained spiropyrazolones was unambiguously characterized with the use of X-ray single-crystal structure analysis. Moreover, the reaction mechanism was assumed to interpret the formation of the target compounds.

12.
Int. j. morphol ; 38(6): 1668-1675, Dec. 2020. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1134496

RESUMO

SUMMARY: The Mettl3/Mettl14 methyltransferase complex installs the most ubiquitous internal mRNA modification- N6-methyladenosine (m6A). The vertebrate retina development is a multi-step process that requires fine-tuning of multiple cellular events, but very little is known about the potential function of Mettl3 and Mettl14 in this process. In this study, we demonstrated the spatio-temporal expression of Mettl3 and Mettl14 during retina development in mouse by quantitative PCR and immunofluorescence staining. We found that these two components of methyltransferase complex could be detected from the beginning of retina development; and the expression of Mettl3 and Mettl14 were gradually restricted to inner nuclear layer (INL) and ganglion cell layer (GCL); Double labeling showed that Mettl3 and Mettl14 had similar expression patterns in mature retinal INL and GCL. Overall, our spatio-temporal expression data provided the foundation for future research on the function of m6A modification in the retina development.


RESUMEN: El complejo Mettl3 / Mettl14 metiltransferasa establece la modificación interna más significativa de ARNm: N6- metiladenosina (m6A). El desarrollo de la retina de los vertebrados es un proceso de varios pasos que requiere múltiples eventos celulares; existe muy poca información sobre la función potencial de Mettl3 y Mettl14 en este proceso. En este estudio, demostramos la expresión espacio-temporal de Mettl3 y Mettl14 durante el desarrollo de la retina en ratón mediante PCR cuantitativa y tinción de inmunofluorescencia. Descubrimos que estos dos componentes del complejo de metiltransferasa podían ser detectados desde el comienzo del desarrollo de la retina; la expresión de Mettl3 y Mettl14 se restringió gradualmente a la capa nuclear interna (INL) y la capa de células ganglionares (GCL); se observó que Mettl3 y Mettl14 tenían patrones de expresión similares en INL y GCL retinianos maduros. En general, nuestros datos de expresión espacio-temporal proporcionan información para futuras investigaciones sobre la función de la modificación de m6A en el desarrollo de la retina.

13.
Transbound Emerg Dis ; 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-33190404

RESUMO

Bluetongue virus (BTV) is the 'type' species of the genus Orbivirus causing bluetongue (BT) in sheep, bovine and other ruminants. Twenty-four serotypes and several atypical serotypes of BTV were identified worldwide. In present study, a novel strain of BTV (V196/XJ/2014) was isolated from an asymptomatic sentinel goat in Yuli County, Xinjiang of China. Serotype identification of this isolate exhibited uniform negative results by serotype specific conventional RT-PCR and real time RT-PCR for BTV-1 to BTV-27, and virus neutralization tests using reference sera of BTV-1 to BTV-24. Genomic analysis showed V196/XJ/2014 grouped with atypical serotypes of BTV-25 to BTV-28, BTV-X/XJ1407, BTV-X/ITL2015 and BTV-Y/TUN2017, while segment 2 and VP2 protein of V196/XJ/2014 shared less than 63.4/61.4% nucleic acids and amino acids sequence identities with other recognized BTV serotypes and its segment 2 formed a separate 'nucleotype' in phylogenetic tree. These results indicated V196/XJ/2014 does not belong to any reported serotypes of BTV. Further studies of infectivity and pathogenicity showed that goats infected with V196/XJ/2014 did not exhibit observed clinical symptoms, but high level of virus amplification and homologous neutralization antibodies were detected post infection. Our studies suggested a novel putative serotype of BTV-29 was isolated in Xinjiang of China, which expands our knowledge about the diversity of BTV.

14.
Int Immunopharmacol ; : 107129, 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33199234

RESUMO

It has been reported that cyclic stretch could induce inflammatory reaction in human periodontal ligament cells (HPDLCs). Though reactive oxygen species (ROS) has been reported to be involved in pathogen-induced periodontal inflammatory reaction, its role in the force-related periodontal diseases has not been well clarified. This study inspected the role of ROS in the cyclic stretch-induced inflammatory reaction in HPDLCs and studied the inhibitory effect of antioxidant apocynin on this inflammatory reaction. Results confirmed that cyclic stretch induced inflammatory reaction and production of ROS in HPDLCs. This inflammatory reaction was inhibited by apocynin through blocking the production of ROS. The cyclic stretch also induced the expression of caspase-1 and NLRP3 inflammasome, which could also be inhibited by apocynin. Moreover, the cyclic stretch-induced inflammatory reaction was inhibited by caspase-1 inhibitor. Collectively, it is the first time that increased intracellular ROS was proved to play as an intermediate signal in the cyclic stretch-induced inflammatory reaction in HPDLCs, via a caspase-1-dependent pathway. The inhibitory effect of apocynin on the cyclic stretch-induced inflammatory reaction in HPDLCs shows the potential of antioxidants in the treatment of force-related periodontal inflammatory diseases.

15.
Plant Sci ; 301: 110679, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33218642

RESUMO

Although the UV RESISTANCE LOCUS 8 (UVR8)-CONSTITUTIVELY PHOTOMORPHOGENIC1 (COP1)-ELONGATED HYPOCOTYL5 (HY5) signaling pathway, ethylene, hydrogen peroxide (H2O2), and nitric oxide (NO) all participate in ultraviolet-B (UV-B)-triggered stomatal closing, their interrelationship is not clear. Here, we found that UV-B-induced the expression of ethylene biosynthetic genes, production of ethylene, H2O2, and NO, and stomata closing were impaired in uvr8, cop1, and hy5 mutants. UV-B-induced NO production and stomata closing were also defective in mutants for ETHYLENE RESPONSE 1 (ETR1), ETHYLENE INSENSITIVE 2 (EIN2), and EIN3, but UV-B-triggered H2O2 generation was only inhibited in etr1. In either the absence or presence of UV-B, ethylene triggered H2O2 production but not NO generation and stomatal closure in cop1 and hy5, and stomata closing in cop1 and hy5 was induced by NO but not H2O2. Moreover, NO production and stomatal closure were constitutively caused by over-expression of COP1 or HY5 in ein2 and ein3, but not by over-expression of EIN2 or EIN3 in cop1 and hy5. Our data indicate that the UVR8-COP1-HY5 signaling module mediates UV-B-induced ethylene production, ethylene is then perceived by ETR1 to induce H2O2 synthesis. H2O2 induces NO generation and subsequent stomata closing via an EIN2, EIN3, COP1, and HY5-dependent pathway(s).

16.
ACS Appl Mater Interfaces ; 12(47): 52457-52466, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33180456

RESUMO

Polyphenolic molecules have become attractive building blocks for bioinspired materials due to their adhesive characteristics, capacity to complex ions, redox chemistry, and biocompatibility. For the formation of tannic acid (TA) surface modifications based on silicate-phenolic networks, a high ionic strength is required. In this study, we investigated the effects of NaCl, KCl, and LiCl on the formation of TA coatings and compared it to the coating formation of pyrogallol (PG) using a quartz-crystal microbalance. We found that the substitution of NaCl with KCl inhibited the TA coating formation through the high affinity of K+ to phenolic groups resulting in complexation of TA. Assessment of the radical formation of TA by electron paramagnetic resonance spectroscopy showed that LiCl resulted in hydrolysis of TA forming gallic acid radicals. Further, we found evidence for interactions of LiCl with the Siaq crosslinker. In contrast, the coating formation of PG was only little affected by the substitution of NaCl with LiCl or KCl. Our results demonstrate the interaction potential between alkali metal salts and phenolic compounds and highlight their importance in the continuous deposition of silicate-phenolic networks. These findings can be taken as guidance for future biomedical applications of silicate-phenolic networks involving monovalent ions.

17.
Infect Dis Poverty ; 9(1): 151, 2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-33148337

RESUMO

BACKGROUND: Many studies have compared the performance of time series models in predicting pulmonary tuberculosis (PTB), but few have considered the role of meteorological factors in their prediction models. This study aims to explore whether incorporating meteorological factors can improve the performance of time series models in predicting PTB. METHODS: We collected the monthly reported number of PTB cases and records of six meteorological factors in three cities of China from 2005 to 2018. Based on this data, we constructed three time series models, including an autoregressive integrated moving average (ARIMA) model, the ARIMA with exogenous variables (ARIMAX) model, and a recurrent neural network (RNN) model. The ARIMAX and RNN models incorporated meteorological factors, while the ARIMA model did not. The mean absolute percentage error (MAPE) and root mean square error (RMSE) were used to evaluate the performance of the models in predicting PTB cases in 2018. RESULTS: Both the cross-correlation analysis and Spearman rank correlation test showed that PTB cases reported in the study areas were related to meteorological factors. The predictive performance of both the ARIMA and RNN models was improved after incorporating meteorological factors. The MAPEs of the ARIMA, ARIMAX, and RNN models were 12.54%, 11.96%, and 12.36% in Xuzhou, 15.57%, 11.16%, and 14.09% in Nantong, and 9.70%, 9.66%, and 12.50% in Wuxi, respectively. The RMSEs of the three models were 36.194, 33.956, and 34.785 in Xuzhou, 34.073, 25.884, and 31.828 in Nantong, and 19.545, 19.026, and 26.019 in Wuxi, respectively. CONCLUSIONS: Our study revealed a possible link between PTB and meteorological factors. Taking meteorological factors into consideration increased the accuracy of time series models in predicting PTB, and the ARIMAX model was superior to the ARIMA and RNN models in study settings.

18.
Artigo em Inglês | MEDLINE | ID: mdl-33211468

RESUMO

Mussel-inspired poly(catecholamine) coatings from polydopamine (PDA) have been widely studied to design functional coatings for various materials. The chemical precursor of dopamine (DA), levodopa (l-DOPA, 3,4-dihydroxyphenyl-l-alanine), is known as the main element of mussel adhesive foot protein, but it is relatively hard to be constructed into a desirable coating on a given material surface under the same conditions as those for DA. Herein, we report a codeposition strategy to achieve the rapid fabrication of mussel-inspired coatings by l-DOPAwith polyethyleneimine (PEI) and to deeply understand the formation mechanism of those aggregates and coatings from l-DOPA/PEI. DFT calculations, fluorescence spectra, nuclear magnetic resonance analysis, and liquid chromatography-tandem mass spectrometry identification demonstrate that the formation of l-DOPA/PEI aggregates is effectively accelerated by PEI crosslinking with those intermediates of oxidized l-DOPA, including l-DOPAquinone and 5,6-dihydroxyindole-2-carboxylic acid as well as 5,6-dihydroxyindole, through Michael-addition and Schiff-base reactions. Therefore, we can facilely control the growth rate and the particle size of the l-DOPA/PEI aggregates in the deposition solution by adjusting the concentration of PEI. The coating formation rate of l-DOPA/PEI is four times faster than that of PDA and DA/PEI within 12 h. These l-DOPA/PEI coatings are demonstrated to display potential as structure colors, superhydrophilic surfaces, and antibacterial materials.

19.
Nano Lett ; 20(12): 8760-8767, 2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33211495

RESUMO

Organic solvent nanofiltration (OSN) is regarded as a promising separation technology in chemical and pharmaceutical industries. However, it remains a great challenge in fabricating OSN membranes with high permeability and precise selectivity by simple, transfer-free, and up-scalable processes. Herein, we report lysozyme nanofilm composite membranes (LNCM) prepared by one-step methods with hydrophobic substrates at the air/water interface. The microporous substrates not only promote the heterogeneous nucleation of amyloid-like lysozyme oligomers to construct small pores in the formed nanofilms but also benefit for the simultaneous composition of LNCM via hydrophobic interactions. The constructed nanopores are reduced to around 1.0 nm, and they are demonstrated by grazing incidence small-angle X-ray scattering with a closely packed model. The LNCM can tolerate most organic polar solvents and the permeability surpasses most of state-of-the-art OSN membranes.

20.
Artigo em Inglês | MEDLINE | ID: mdl-33251561

RESUMO

The Simon effect is a stimulus-response compatibility effect in which the spatial dimension of the stimulus is task-irrelevant. This effect is often larger in reaction time (RT) for the stimulus located on the dominant-hand side of participants, for most of which it is the right hand, due to dominant-hand keypress responses being faster than non-dominant-hand responses. Experiment 1 demonstrated that pedal-press responses with the left and right feet show a similar asymmetry, favoring the right response for right-footed persons. The asymmetric pattern for keypress responses was absent in results of Wallace (Journal of Experimental Psychology, 93, 163-168, 1972) when participants were not permitted to see the response keys or their hands placed on the keys at any time during the experiment, whereas we found the asymmetric pattern in a recent study when participants placed their hands on the keys prior to their being covered up. Experiments 2 and 3 showed that the Simon effect asymmetry for RT was evident even when participants were prevented from seeing the response device and their responding hands or feet. Although both hands and feet showed a Simon effect asymmetry in RT, consideration of incorrect responses suggested that whereas the asymmetry for hands is not due to a response bias, that for the feet may be due at least in part to such bias. Regardless, our results suggest that the Simon effect asymmetry is mainly an artifact of comparing conditions for which one response is made by the faster dominant right effector and the other with the slower non-dominant left effector.

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