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1.
Artigo em Inglês | MEDLINE | ID: mdl-38723291

RESUMO

To solve the problem of ice condensation and adhesion, it is urgent to develop new anti-icing and deicing technologies. This study presented the development of a highly efficient photothermal-enhanced superhydrophobic PDMS/Ni@Ti3C2Tx composite film (m-NMPA) fabricated cost-effectively and straightforwardly. This film was fabricated utilizing PDMS as a hydrophobic agent, adhesive, and surface protector, while Ni@Ti3C2Tx as a magnetic photothermal filler innovatively. Through a simple spraying method, the filler is guided by a strong magnetic field to self-assemble into an eyelash-like microstructure array. The unique structure not only imparts superhydrophobic properties to the surface but also constructs an efficient "light-capturing" architecture. Remarkably, the m-NMPA film demonstrates outstanding superhydrophobic passive anti-icing and efficient photothermal active deicing performance without the use of fluorinated chemicals. The micro-/nanostructure of the film forms a gas layer, significantly delaying the freezing time of water. Particularly under extreme cold conditions (-30 °C), the freezing time is extended by a factor of 7.3 compared to the bare substrate. Furthermore, under sunlight exposure, surface droplets do not freeze. The excellent photothermal performance is attributed to the firm anchoring of nickel particles on the MXene surface, facilitating effective "point-to-face" photothermal synergy. The eyelash-like microarray structure enhances light-capturing capability, resulting in a high light absorption rate of 98%. Furthermore, the microstructure aids in maintaining heat at the uppermost layer of the surface, maximizing the utilization of thermal energy for ice melting and frost thawing. Under solar irradiation, the m-NMPA film can rapidly melt approximately a 4 mm thick ice layer within 558 s and expel the melted water promptly, reducing the risk of secondary icing. Additionally, the ice adhesion force on the surface of the m-NMPA film is remarkably low, with an adhesion strength of approximately 4.7 kPa for a 1 × 1 cm2 ice column. After undergoing rigorous durability tests, including xenon lamp weathering test, pressure resistance test, repeated adhesive tape testing, xenon lamp irradiation, water drop impact testing, and repeated brushing with hydrochloric acid and particles, the film's surface structure and superhydrophobic performance have remained exceptional. The photothermal superhydrophobic passive anti-icing and active deicing technology in this work rely on sustainable solar energy for efficient heat generation. It presents broad prospects for practical applications with advantages such as simple processing method, environmental friendliness, outstanding anti-icing effects, and exceptional durability.

2.
Front Psychol ; 14: 1170669, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37560098

RESUMO

Introduction: Though the important effect of cultural identity on subjective well-being is widely acknowledged, the details of how different cultures' unique features influence well-being remain to be revealed. To address this issue in the context of Chinese culture, the present study investigates whether and how the prominent features of Chinese culture-collectivism and red culture-shape Chinese people's subjective well-being. Methods: The Red Cultural Identity Scale, Subjective Well-Being Scale, Collectivism Scale, and Perspective-Taking Scale were used to assess 1,045 Chinese residents. Results: The results showed that red cultural identity positively predicted participants' subjective well-being through the mediated role of collectivism. Furthermore, perspective-taking was found to moderate the mediating effect of collectivism. Discussion: These results demonstrate that the way cultural identity predicts subjective well-being is highly correlated to specific cultural features, e.g., the opinion of values, which was significant in practice with a cross-cultural background.

3.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 31(8): 983-988, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31537224

RESUMO

OBJECTIVE: To explore the immunomodulatory effects of interleukin-17 (IL-17) on acute lung injury (ALI) induced by lipopolysaccharide (LPS). METHODS: Thirty-six SPF-class C57BL/6 mice were divided into normal saline control group (NS group) and LPS-induced ALI model group (LPS group, LPS 5 mg/kg intratracheal drip) according to random number table method, with 18 mice in each group. Six mice were sacrificed at 2, 6 and 24 hours after model reproduction, and peripheral blood, lung and spleen tissues were harvested. After staining with hematoxylin-eosin (HE), the pathological changes of lung tissue were observed under microscope and the infiltration level of lymphocytes, neutrophils and macrophages in the alveolar wall and tracheal wall were detected. Immunohistochemistry was used to detect the protein expression of IL-17 in alveolar wall and tracheal wall, and the correlation between IL-17 expression and lymphocytes, neutrophils and macrophages infiltration in alveolar wall and tracheal wall were analyzed. The level of IL-17 in lung tissue homogenate was determined by enzyme linked immunosorbent assay (ELISA). Flow cytometry was used to detect the proportion of CD4+IL-17+ helper T cells (Th17 cells) in CD4+ T cells in peripheral blood, lung tissue and spleen tissue. RESULTS: (1) Microscopy showed that the lung tissue structure of NS group was basically normal at each time after model reproduction, and there was no obvious inflammatory cell infiltration, while the lung tissue edema and inflammatory reaction were gradually aggravated in the LPS group, and the lung injury score was significantly higher than that in NS group at each time (2 hours: 4.47±1.42 vs. 1.10±0.55, 6 hours: 7.93±2.14 vs. 1.23±0.50, 24 hours: 12.67±2.67 vs. 1.20±0.61, all P < 0.01). (2) Immunohistochemistry showed that the protein expression of IL-17 in alveolar wall and tracheal wall of LPS group increased gradually with time, while that in NS group was negative or weak positive. Quantitative analysis showed that the immunohistochemical staining score of IL-17 protein in alveolar wall and tracheal wall of LPS group were higher than those of NS group (alveolar wall: 2.70±1.40 vs. 0.90±0.37 at 2 hours, 5.10±1.76 vs. 1.17±0.59 at 6 hours, 9.67±1.32 vs. 1.10±0.45 at 24 hours; tracheal wall: 2.87±0.89 vs. 0.90±0.39 at 2 hours, 4.97±1.48 vs. 1.10±0.41 at 6 hours, 8.67±1.54 vs. 1.03±0.29 at 24 hours; all P < 0.05). (3) Correlation analysis showed that the protein expression of IL-17 in alveolar wall and tracheal wall were positively correlated with the degree of lymphocyte, neutrophil and macrophage infiltration (alveolar wall: r value was 0.632, 0.550, 0.466; tracheal wall: r value was 0.695, 0.662, 0.575, respectively; all P < 0.01). (4) IL-17 content (µg/L) in lung tissue homogenate was significantly higher than that in NS group at each time after model reproduction (2 hours: 1.37±0.14 vs. 1.01±0.18, 6 hours: 1.65±0.19 vs. 1.11±0.18, 24 hours: 1.92±0.36 vs. 1.17±0.24, all P < 0.01). (5) The proportion of Th17 cells in the peripheral blood, lung tissue and spleen tissue of the LPS group were higher than those of the NS group at each time after model reproduction [peripheral blood: (2.62±0.62)% vs. (1.42±0.40)% at 2 hours, (3.74±0.43)% vs. (1.27±0.32)% at 6 hours, (4.44±0.65)% vs. (1.59±0.45)% at 24 hours; lung tissue: (2.32±0.44)% vs. (1.50±0.25)% at 2 hours, (3.66±0.36)% vs. (1.33±0.24)% at 6 hours, (4.60±0.54)% vs. (1.60±0.27)% at 24 hours; spleen tissue: (1.49±0.36)% vs. (0.69±0.21)% at 2 hours, (2.58±0.55)% vs. (0.59±0.18)% at 6 hours, (3.76±0.57)% vs. (0.65±0.26)% at 24 hours; all P < 0.01]. CONCLUSIONS: IL-17 is involved in the inflammatory immune regulation of ALI mice.


Assuntos
Lesão Pulmonar Aguda/metabolismo , Interleucina-17/metabolismo , Animais , Lipopolissacarídeos , Pulmão , Camundongos , Camundongos Endogâmicos C57BL , Fator de Necrose Tumoral alfa
4.
Sheng Wu Gong Cheng Xue Bao ; 31(1): 24-42, 2015 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-26021077

RESUMO

Chlorella is nutritious and has been used as a functional food much earlier than the other microalgae. C. pyrenoidosa, the potential microalgae which is currently cultured and developed for the new strategic industry of biofuels production and biological CO2 fixation, is a new resource food announced by the Ministry of Health of the People's Republic of China late 2012. Accumulation of high value-added substances in C. pyrenoidosa during the cultivation for lipid makes it possible to reduce the costs for C. pyrenoidosa-based biofuels production. Among these potential substances, hot water extract of Chlorella (CE), commercially known as "Chlorella growth factor", is the unique one that makes Chlorella more precious than the other algae, and the market price of CE is high. It is believed that CE is effective in growth promotion and immunoregulation. However, there is no systematic analysis on the research status of CE and its bioactivity. The present report summarized recent research progress of CE and its bioactivity. Generally, besides the main effect on immunoregulation and tumor inhibition, CE was efficient in improving metabolic syndrome, scavenging for free radicals, protecting against ultraviolet damage, chelating heavy metals, and protecting liver and bowel. Several major challenges in CE research as well as its prospects were also analysed in the present report.


Assuntos
Biocombustíveis , Chlorella/química , Extratos Vegetais/química , Humanos , Lipídeos/química , Extratos Vegetais/farmacologia , Água
5.
Integr Biol (Camb) ; 3(1): 57-64, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21031221

RESUMO

The mitotic spindle is a dynamic assembly of microtubules and microtubule-associated proteins that controls the directed movement of chromosomes during cell division. Because proper segregation of the duplicated genome requires that each daughter cell receives precisely one copy of each chromosome, numerous overlapping mechanisms have evolved to ensure that every chromosome is transported to the cell equator during metaphase. However, due to the inherent redundancy in this system, cellular studies using gene knockdowns or small molecule inhibitors have an inherent limit in defining the sufficiency of precise molecular mechanisms as well as quantifying aspects of their mechanical performance. Thus, there exists a need for novel experimental approaches that reconstitute important aspects of the mitotic spindle in vitro. Here, we show that by microfabricating Cr electrodes on quartz substrates and micropatterning proteins on the electrode surfaces, AC electric fields can be used to assemble opposed bundles of aligned and uniformly oriented microtubules as found in the mitotic spindle. By immobilizing microtubule ends on each electrode, analogous to anchoring at centrosomes, solutions of motor or microtubule binding proteins can be introduced and their resulting dynamics analyzed. Using this "artificial mitotic spindle" we show that beads functionalized with plus-end kinesin motors move in an oscillatory manner analogous to the movements of chromosomes and severed chromosome arms during metaphase. Hence, features of directional instability, an established characteristic of metaphase chromosome dynamics, can be reconstituted in vitro using a pair of uniformly oriented microtubule bundles and a plus-end kinesin functionalized bead.


Assuntos
Cinesinas/metabolismo , Fuso Acromático/metabolismo , Animais , Transporte Biológico Ativo , Bovinos , Eletroforese , Técnicas In Vitro , Microtúbulos/metabolismo , Mitose/fisiologia , Modelos Biológicos , Proteínas Motores Moleculares/metabolismo , Biologia de Sistemas , Tubulina (Proteína)/metabolismo
6.
Sheng Wu Gong Cheng Xue Bao ; 26(7): 907-13, 2010 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-20954391

RESUMO

With the dwindling of fossil fuels supply and the urgent need for the development of low-carbon economy, microalgae bioenergy, both renewable and environmentally friendly, has become one of the worldwide focuses. Given its benefit to the security of national energy supply, microalgae energy is particularly significant for China, with more than 50% crude oil imported and limited arable land for grain and edible oil production. In this article, both the advantages of microalgae bioenergy and the challenges of its development are addressed, which involves fundamental research and technology development as well as commercial production. Furthermore, strategies are proposed for China's microalgae bioenergy development, and its prospects are projected.


Assuntos
Biocombustíveis , Biotecnologia/tendências , Conservação de Recursos Energéticos/métodos , Microalgas/metabolismo , Biotecnologia/métodos , Microalgas/crescimento & desenvolvimento
7.
Lab Chip ; 8(10): 1745-7, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18813401

RESUMO

We describe a novel approach for directly patterning neutravidin protein by exposure to deep UV irradiation. Neutravidin is physically absorbed onto the glass or quartz substrate, dehydrated in acetone and air-dried. Dry neutravidin-coated samples are patterned either by top-side or back-side exposure to 185 nm UV. Subsequent introduction of fluorescent biotinylated proteins clearly demonstrates binding to the masked neutravidin regions and no binding to exposed areas. Patterned samples retain their protein affinity for at least three months of storage at room temperature.


Assuntos
Avidina/química , Raios Ultravioleta
8.
Small ; 4(9): 1371-81, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18720434

RESUMO

The kinesin-microtubule system plays an important role in intracellular transport and is a model system for integrating biomotor-driven transport into microengineered devices. AC electrokinetics provides a novel tool for manipulating and organizing microtubules in solution, enabling new experimental geometries for investigating and controlling the interactions of microtubules and microtubule motors in vitro. By fabricating microelectrodes on glass substrates and generating AC electric fields across solutions of microtubules in low-ionic-strength buffers, bundles of microtubules are collected and aligned and the electrical properties of microtubules in solution are measured. The AC electric fields result in electro-osmotic flow, electrothermal flow, and dielectrophoresis of microtubules, which can be controlled by varying the solution conductivity, AC frequency, and electrode geometry. By mapping the solution conductivity and AC frequency over which positive dielectrophoresis occurs, the apparent conductivity of taxol-stabilized bovine-brain microtubules in PIPES buffer is measured to be 250 mS m(-1). By maximizing dielectrophoretic forces and minimizing electro-osmotic and electrothermal flow, microtubules are assembled into opposed asters. These experiments demonstrate that AC electrokinetics provides a powerful new tool for kinesin-driven transport applications and for investigating the role of microtubule motors in development and maintenance of the mitotic spindle.


Assuntos
Elétrons , Microtúbulos/química , Animais , Soluções Tampão , Bovinos , Simulação por Computador , Eletrodos , Cinesinas/química , Cinética , Concentração Osmolar , Temperatura , Água/química
9.
Lab Chip ; 8(2): 358-61, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18231678

RESUMO

Biomolecular motors, such as kinesins, have great potential for micro-actuation and micro- or nanoscale active transport when integrated into microscale devices. However, the stability and limited shelf life of these motor proteins and their associated protein filaments is a barrier to their implementation. Here we demonstrate that freeze-drying or critical point-drying kinesins adsorbed to glass surfaces extends their lifetime from days to more than four months. Further, photoresist deposition and removal can be carried out on these motor-adsorbed surfaces without loss of motor function. The methods developed here are an important step towards realizing the integration of biological motors into practical devices, and these approaches can be extended to patterning and preserving other proteins immobilized on surfaces.


Assuntos
Proteínas de Drosophila/química , Cinesinas/química , Microtúbulos/química , Adsorção , Vidro/química , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos , Movimento (Física) , Tamanho da Partícula , Propriedades de Superfície , Fatores de Tempo
10.
Biomed Microdevices ; 9(2): 175-84, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17195111

RESUMO

The kinesin-microtubule system has emerged as a versatile model system for biologically-derived microscale transport. While kinesin motors in cells transport cargo along static microtubule tracks, for in vitro transport applications it is preferable to invert the system and transport cargo-functionalized microtubules along immobilized kinesin motors. However, for efficient cargo transport and to enable this novel transport system to be interfaced with traditional microfluidics, it is important to fabricate enclosed microchannels that are compatible with kinesin motors and microtubules, that enable fluorescence imaging of microtubule movement, and that provide fluidic connections for sample introduction. Here we construct a three-tier hierarchical system of microfluidic channels that links microscale transport channels to macroscopic fluid connections. Shallow microchannels (5 microm wide and 1 microm deep) are etched in a glass substrate and bonded to a cover glass using PMMA as an adhesive, while intermediate channels (approximately 100 microm wide) serve as reservoirs and connect to 250 microm deep microchannels that hold fine gauge tubing for fluid injection. To demonstrate the utility of this device, we first show the performance of a directional rectifier that redirects 96% of moving microtubules and, because any microtubules that detach rapidly rebind to the motor-coated surface, suffers no microtubule loss over time. Second, we develop an approach, using a headless kinesin construct, to eliminate gradients in motor adsorption and microtubule binding in the enclosed channels, which enables precise control of kinesin density in the microchannels. Finally, we show that a 60 microm diameter circular ring functionalized with motors concentrates and aligns bundles of approximately 3000 uniformly oriented microtubules, while suffering negligible ATP depletion. These aligned isopolar microtubules are an important tool for microscale transport applications and can be employed as a model in vitro system for studying kinesin-driven microtubule organization in cells.


Assuntos
Técnicas Analíticas Microfluídicas/instrumentação , Micromanipulação/instrumentação , Microtúbulos/química , Microtúbulos/ultraestrutura , Proteínas Motores Moleculares/química , Proteínas Motores Moleculares/ultraestrutura , Desenho de Equipamento , Análise de Falha de Equipamento , Técnicas Analíticas Microfluídicas/métodos , Micromanipulação/métodos , Complexos Multiproteicos/química , Complexos Multiproteicos/ultraestrutura , Conformação Proteica
11.
Wei Sheng Wu Xue Bao ; 42(3): 359-63, 2002 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-12557380

RESUMO

When Candida tropicalis was cultivated in shakig-flask with the H2O2 addition, DCA (Dicarboxylic Acid, DCA) concentration was increased, especially at 2 mmol/L H2O2 concentration. The cytochrome P450 activity assays indicated that H2O2 addition significantly increased the activities of cytochrome P450 and DCA production positively correlated with the activities of cytochrome P450. The study on the cell growth demonstrated that the H2O2 addition inhibited the cell growth rate. However, the retarding effect was not irreversible since the cell growth rate could recover slowly to the original level after the H2O2 addition was halted. The mechanism of inducement on cytochrome P450 by H2O2 addition was also discussed in this article.


Assuntos
Candida tropicalis/enzimologia , Sistema Enzimático do Citocromo P-450/metabolismo , Ácidos Dicarboxílicos/síntese química , Peróxido de Hidrogênio/metabolismo , Aerobiose , Reatores Biológicos , Candida tropicalis/citologia , Indução Enzimática , Fermentação
12.
J Gen Appl Microbiol ; 46(5): 245-249, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12483575

RESUMO

Techniques, named two-step enrichment and double-time replica-plating method (TEDR), are described that allow a mutated population of Candida tropicalis to be enriched efficiently for mutants deficient in the alkane degradation pathway (Alk(-)) and to be selected easily for mutants increasing in the DCA (dicarboxylic acids) excretion pathway. After C. tropicalis was mutated with ethyl methane sulphonate and ultraviolet, the Alk(-) mutants were enriched (the first step enrichment, up to eightfold in one round of enrichment) by treatment with nystatin in medium SEL1-1. The mutagen-treated cells were then cultured in medium YPD containing chlorpromazine for further enriching (the second-step enrichment, up to threefold in one round) the mutants with an increasing capacity of alpha- and omega-oxidation. On the other hand, the Alk(-) mutants were readily isolated by the SEL1 replica-plating method by using alkane or glucose as the sole carbon source. A total of 43 Alk(-) mutants were isolated from 2x10(8) mutagen-treated cells. In the following steps, by using SEL2 replica plating, the screening studies showed that of the 43 Alk(-) mutants, 11 strains could accumulate DCA greatly from alkane, and strains 1-12 and 1-3, especially, could produce nearly three times as much DCA as the wild-type organism could. The results showed that the strains had more cytochrome P450 activity and a higher converting capacity of alkane.

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