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1.
Biochim Biophys Acta Mol Cell Res ; : 119782, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38871225

RESUMO

Circadian Locomotor Output Cycles Kaput (CLOCK) is one of the circadian clock genes and is considered to be a fundamental regulatory gene in the circadian rhythm, responsible for mediating several biological processes. Therefore, abnormal expression of CLOCK affects its role in the circadian clock and its more general function as a direct regulator of gene expression. This dysfunction can lead to severe pathological effects, including cancer. To better understand the role of CLOCK in cancer, we compiled this review to describe the biological function of CLOCK, and especially highlighted its function in cancer development, progression, tumor microenvironment, cancer cell metabolism, and drug resistance.

2.
Sci Adv ; 10(18): eadj8395, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38701213

RESUMO

The development of radiation-tolerant structural materials is an essential element for the success of advanced nuclear energy concepts. A proven strategy to increase radiation resistance is to create microstructures with a high density of internal defect sinks, such as grain boundaries (GBs). However, as GBs absorb defects, they undergo internal transformations that limit their ability to capture defects indefinitely. Here, we show that, as the sink efficiency of GBs becomes exhausted with increasing irradiation dose, networks of irradiation loops form in the vicinity of saturated or near-saturated GB, maintaining and even increasing their capacity to continue absorbing defects. The formation of these networks fundamentally changes the driving force for defect absorption at GB, from "chemical" to "elastic." Using thermally-activated dislocation dynamics simulations, we show that these networks are consistent with experimental measurements of defect densities near GB. Our results point to these networks as a natural continuation of the GB once they exhaust their internal defect absorption capacity.

3.
Adv Sci (Weinh) ; : e2402196, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38650164

RESUMO

Fiber-based artificial muscles are promising for smart textiles capable of sensing, interacting, and adapting to environmental stimuli. However, the application of current artificial muscle-based textiles in wearable and engineering fields has largely remained a constraint due to the limited deformation, restrictive stimulation, and uncomfortable. Here, dual-responsive yarn muscles with high contractile actuation force are fabricated by incorporating a very small fraction (<1 wt.%) of Ti3C2Tx MXene/cellulose nanofibers (CNF) composites into self-plied and twisted wool yarns. They can lift and lower a load exceeding 3400 times their own weight when stimulated by moisture and photothermal. Furthermore, the yarn muscles are coiled homochirally or heterochirally to produce spring-like muscles, which generated over 550% elongation or 83% contraction under the photothermal stimulation. The actuation mechanism, involving photothermal/moisture-mechanical energy conversion, is clarified by a combination of experiments and finite element simulations. Specifically, MXene/CNF composites serve as both photothermal and hygroscopic agents to accelerate water evaporation under near-infrared (NIR) light and moisture absorption from ambient air. Due to their low-cost facile fabrication, large scalable dimensions, and robust strength coupled with dual responsiveness, these soft actuators are attractive for intelligent textiles and devices such as self-adaptive textiles, soft robotics, and wearable information encryption.

4.
J Back Musculoskelet Rehabil ; 37(1): 137-146, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37840481

RESUMO

BACKGROUND: Muscle imbalance has long been recognized as one of the possible pathogeneses for adolescent idiopathic scoliosis (AIS). PIEZO2, the susceptibility gene of AIS, has been identified to play an important role in neuromuscular activities. OBJECTIVE: This study aims to compare the mRNA expression of PIEZO2 between concave and convex paraspinal muscles of AIS patients and to identify the relationship between the ratio of PIEZO2 expression and curve magnitude. METHODS: Twenty female AIS patients (right thoracic curve) who underwent spinal correction surgery were divided into moderate (n= 12) and severe (⩾ 70 degrees) curve groups (n= 8). The morphology of the paraspinal muscles was assessed with spinal MRI. Multifidus specimens were collected during surgical operations from the concave and convex sides of the apical region, and mRNA expression of the PIEZO2 gene was compared between sides. The localization of PIEZO2 protein expression was confirmed with the markers PAX7 and PAX3, and the percentage of PIEZO2+ cells was also investigated. RESULTS: In the moderate curve group, fatty infiltration in the deep paraspinal muscle was significantly higher on the concave side than on the convex side. There were no differences in deep muscle area, superficial muscle area, or fatty infiltration of superficial paraspinal muscle. The mRNA expression of PIEZO2 was significantly increased on the concave side, and the asymmetric expression predominantly occurred in moderate curves rather than severe ones. PIEZO2 was expressed on satellite cells instead of fibers of the muscle spindle. The percent of PIEZO2+PAX7+ cells in myofibers was significantly higher on the concave side in the moderate curve group, but not in the severe curve group. CONCLUSIONS: Asymmetric morphological changes occur in the deep paraspinal muscles of AIS. The PIEZO2 is asymmetrically expressed in the multifidus muscle and is preferentially expressed in satellite cells.


Assuntos
Cifose , Escoliose , Humanos , Adolescente , Feminino , Escoliose/genética , Músculos Paraespinais/metabolismo , Coluna Vertebral , RNA Mensageiro/metabolismo , Canais Iônicos/genética , Canais Iônicos/metabolismo
5.
Adv Mater ; : e2307963, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37971199

RESUMO

Soft grippers are essential for precise and gentle handling of delicate, fragile, and easy-to-break objects, such as glassware, electronic components, food items, and biological samples, without causing any damage or deformation. This is especially important in industries such as healthcare, manufacturing, agriculture, food handling, and biomedical, where accuracy, safety, and preservation of the objects being handled are critical. This article reviews the use of 3D printing technologies in soft grippers, including those made of functional materials, nonfunctional materials, and those with sensors. 3D printing processes that can be used to fabricate each class of soft grippers are discussed. Available 3D printing technologies that are often used in soft grippers are primarily extrusion-based printing (fused deposition modeling and direct ink writing), jet-based printing (polymer jet), and immersion printing (stereolithography and digital light processing). The materials selected for fabricating soft grippers include thermoplastic polymers, UV-curable polymers, polymer gels, soft conductive composites, and hydrogels. It is conclude that 3D printing technologies revolutionize the way soft grippers are being fabricated, expanding their application domains and reducing the difficulties in customization, fabrication, and production.

6.
ACS Nano ; 17(18): 17920-17930, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37668183

RESUMO

Autonomous object manipulation and perception with environmental factor-triggered and self-powered actuation is one of the most attractive directions for developing next-generation soft robotics with a smart human-machine-environment interface. Humidity, as a sustainable energy source ubiquitous in the surrounding environment, can be used for triggering smart grippers. In this work, it is proposed that by contacts between the gripper and objects upon humidity-induced actuation, real-time distinguishable triboelectric signals can be generated to realize the humidity-driven object manipulation and identification. Herein, a thermo-modified electrospun polyvinylpyrrolidone/poly(acrylic acid)/MIL-88A (T-PPM) nanofibrous film with micro-to-nano cross-scale porosity is developed, and a bilayer humidity-responsive actuator (T-HRA) was designed, mimicking the tamariskoid spikemoss to enhance the humidity-driven actuation. The breathing effect of MIL-88A and hierarchical porous structure of the T-PPM facilitate moisture diffusion and offer huge actuation (2.41 cm-1) with a fast response (0.084 cm-1 s-1). For autonomous object manipulation perception, T-PPM was verified as a tribo-positive material located between paper and silk. Accordingly, the T-HRA was demonstrated as a smart soft gripper that generates a different electric signal upon contact with objects of different material. This work proposes a concept of soft robots that are interactive with the environment for both autonomous object manipulation and information acquisition.

7.
Nat Plants ; 9(10): 1760-1775, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37749240

RESUMO

Accurate delineation of plant cell organelles from electron microscope images is essential for understanding subcellular behaviour and function. Here we develop a deep-learning pipeline, called the organelle segmentation network (OrgSegNet), for pixel-wise segmentation to identify chloroplasts, mitochondria, nuclei and vacuoles. OrgSegNet was evaluated on a large manually annotated dataset collected from 19 plant species and achieved state-of-the-art segmentation performance. We defined three digital traits (shape complexity, electron density and cross-sectional area) to track the quantitative features of individual organelles in 2D images and released an open-source web tool called Plantorganelle Hunter for quantitatively profiling subcellular morphology. In addition, the automatic segmentation method was successfully applied to a serial-sectioning scanning microscope technique to create a 3D cell model that offers unique views of the morphology and distribution of these organelles. The functionalities of Plantorganelle Hunter can be easily operated, which will increase efficiency and productivity for the plant science community, and enhance understanding of subcellular biology.


Assuntos
Aprendizado Profundo , Microscopia Eletrônica , Núcleo Celular , Mitocôndrias , Cloroplastos
8.
Adv Mater ; 35(31): e2302815, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37272692

RESUMO

The tribovoltaic nanogenerator (TVNG), a promising semiconductor energy technology, displays outstanding advantages such as low matching impedance and continuous direct-current output. However, the lack of controllable and stable performance modulation strategies is still a major bottleneck that impedes further practical applications of TVNG. Herein, by leveraging the ferroelectricity-enhanced mechanism and the control of interfacial energy band bending, a lead-free perovskite-based (3,3-difluorocyclobutylammonium)2 CuCl4 ((DF-CBA)2 CuCl4 )/Al Schottky junction TVNG is constructed. The multiaxial ferroelectricity of (DF-CBA)2 CuCl4 enables an excellent surface charge modulating capacity, realizing a high work function regulation of ≈0.7 eV and over 15-fold current regulation (from 6 to 93 µA) via an electrical poling control. The controllable electrical poling leads to elevated work function difference between the Al electrode and (DF-CBA)2 CuCl4 compared to traditional semiconductors and halide perovskites, which creates a stronger built-in electric field at the Schottky interface to enhance the electrical output. This TVNG device exhibits outstanding flexibility and long-term stability (>20 000 cycles) that can endure extreme mechanical deformations, and can also be used in a capsule-like magnetic suspension device capable of detecting vibration and weights of different objects as well as harvesting energy from human motions and water waves.

9.
Front Pharmacol ; 14: 1154135, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37188263

RESUMO

With the increase in human lifespan and the aggravation of global aging, the incidence of osteoarthritis (OA) is increasing annually. To better manage and control the progression of OA, prompt diagnosis and treatment for early-stage OA are important. However, a sensitive diagnostic modality and therapy for early OA have not been well developed. The exosome is a class of extracellular vesicles containing bioactive substances, that can be delivered directly from original cells to neighboring cells to modulate cellular activities through intercellular communication. In recent years, exosomes have been considered important in the early diagnosis and treatment of OA. Synovial fluid exosome and its encapsulated substances, e.g., microRNA, lncRNA, and proteins, can not only distinguish OA stages but also prevent the progression of OA by directly targeting cartilage or indirectly modulating the immune microenvironment in the joints. In this mini-review, we include recent studies on the diagnostic and therapeutic modalities of exosomes and hope to provide a new direction for the early diagnosis and treatment of OA disease in the future.

10.
Bioeng Transl Med ; 8(1): e10346, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36684074

RESUMO

Urological chronic pelvic pain syndrome (UCPPS) manifests as pelvic pain with frequent urination and has a 10% prevalence rate without effective therapy. Nanoceria (cerium oxide nanoparticles [CNPs]) were synthesized in this study to achieve potential long-term pain relief, using a commonly used UCPPS mouse model with cyclophosphamide-induced cystitis. Transcriptome sequencing analysis revealed that serpin family B member 2 (SerpinB2) was the most upregulated marker in mouse bladder, and SerpinB2 was downregulated with CNP pretreatment. The transcriptome sequencing analysis results agreed with quantitative polymerase chain reaction and western blot analysis results for the expression of related mRNAs and proteins. Analysis of Gene Expression Omnibus (GEO) datasets revealed that SerpinB2 was a differentially upregulated gene in human UCPPS. In vitro SerpinB2 knockdown downregulated proinflammatory chemokine expression (chemokine receptor CXCR3 and C-X-C motif chemokine ligand 10) upon treatment with 4-hydroperoxycyclophosphamide. In conclusion, CNP pretreatment may prevent the development of UCPPS, and reactive oxygen species (ROS) scavenging and SerpinB2 downregulation may modulate the immune response in UCPPS.

11.
Front Public Health ; 10: 996169, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36530701

RESUMO

Objective: The West China Hospital of Sichuan University collaborated with regional medical consortia in Sichuan Province to launch a natural population cohort study (NPCS) to investigate the health status of residents and collect public health data in southwest China. Methods: Up to 80,000 participants will be enrolled by the NPCS from 11 regional medical consortia over five years. Individuals are invited to visit one of 11 participating medical consortia to fill out questionnaires, receive a free health exam, and donate biospecimens upon enrolment. All participating medical facilities adhered to standard operating procedures for collecting and processing biospecimens to ensure uniformity (serum, lithium heparinized plasma, ethylene diamine tetraacetie acid plasma, and buffy coat). The Electronic Data Capture System, Picture Archiving and Communication System, Laboratory Information Management System, Biospecimen Quality Control System, Biobank Information Management System, and will be used to sort and classify clinical indices, imaging data, laboratory parameters, pre-analytical variables, and biospecimen information, respectively. All quality assurance and quality control procedures in the NPCS biobank adhered to the "DAIDS Guidelines for Good Clinical Laboratory Practice Standards". This project will integrate high-dimensional multi-omics data, laboratory data, clinical data, questionnaire data, and environmental risk factors. Results: An estimated 2,240,000 aliquots of the sample will be stored by the end of the study. These samples are linked with comprehensively collected clinical indices, imaging data, and laboratory parameters. Big data analysis can be implemented to create predictive algorithms, explore pathogenesis mechanisms, uncover potential biomarkers, and provide information on public health. Conclusions: NPCS will provide an integrative approach to research risk factors and pathogenesis of major chronic or endemic diseases in Sichuan Province and provide key scientific evidence to support the formulation of health management policies in China.


Assuntos
Bancos de Espécimes Biológicos , Humanos , Estudos de Coortes , Inquéritos e Questionários , Biomarcadores , China
12.
Nat Commun ; 13(1): 5607, 2022 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-36153340

RESUMO

Piezoelectric materials convert mechanical stress to electrical energy and thus are widely used in energy harvesting and wearable devices. However, in the piezoelectric family, there are two pairs of properties that improving one of them will generally compromises the other, which limits their applications. The first pair is piezoelectric strain and voltage constant, and the second is piezoelectric performance and mechanical softness. Here, we report a molecular bond weakening strategy to mitigate these issues in organic-inorganic hybrid piezoelectrics. By introduction of large-size halide elements, the metal-halide bonds can be effectively weakened, leading to a softening effect on bond strength and reduction in polarization switching barrier. The obtained solid solution C6H5N(CH3)3CdBr2Cl0.75I0.25 exhibits excellent piezoelectric constants (d33 = 367 pm/V, g33 = 3595 × 10-3 Vm/N), energy harvesting property (power density is 11 W/m2), and superior mechanical softness (0.8 GPa), promising this hybrid as high-performance soft piezoelectrics.

13.
Materials (Basel) ; 15(15)2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-35955403

RESUMO

In this work, we study vacancy energetics in the equiatomic Nb-Mo-Ta-W alloy, especially vacancy formation and migration energies, using molecular statics calculations based on a spectral neighbor analysis potential specifically developed for Nb-Mo-Ta-W. We consider vacancy properties in bulk environments as well as near edge dislocation cores, including the effect of short-range order (SRO) by preparing supercells through Metropolis Monte-Carlo relaxations and temperature on the calculation. The nudged elastic band (NEB) method is applied to study vacancy migration energies. Our results show that both vacancy formation energies and vacancy migration energies are statistically distributed with a wide spread, on the order of 1.0 eV in some cases, and display a noticeable dependence on SRO. We find that, in some cases, vacancies can form with very low energies at edge dislocation cores, from which we hypothesize the formation of stable 'superjogs' on edge dislocation lines. Moreover, the large spread in vacancy formation energies results in an asymmetric thermal sampling of the formation energy distribution towards lower values. This gives rise to effective vacancy formation energies that are noticeably lower than the distribution averages. We study the effect that this phenomenon has on the vacancy diffusivity in the alloy and discuss the implications of our findings on the structural features of Nb-Mo-Ta-W.

14.
Adv Mater ; 34(17): e2200042, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35231951

RESUMO

Halide-perovskite-based mechanical energy harvesters display excellent electrical output due to their unique ferroelectricity and dielectricity. However, their high toxicity and moisture sensitivity impede their practical applications. Herein, a stretchable, breathable, and stable nanofiber composite (LPPS-NFC) is fabricated through electrospinning of lead-free perovskite/poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) and styrene-ethylene-butylene-styrene (SEBS). The Cs3 Bi2 Br9 perovskites serve as efficient electron acceptors and local nucleating agents for the crystallization of polymer chains, thereby enhancing the electron-trapping capacity and polar crystalline phase in LPPS-NFC. The excellent energy level matching between Cs3 Bi2 Br9 and PVDF-HFP boosts the electron transfer efficiency and reduces the charge loss, thereby promoting the electron-trapping process. Consequently, this LPPS-NFC-based energy harvester displays an excellent electrical output (400 V, 1.63 µA cm-2 , and 2.34 W m-2 ), setting a record of the output voltage among halide-perovskite-based nanogenerators. The LPPS-NFC also exhibits excellent stretchability, waterproofness, and breathability, enabling the fabrication of robust wearable devices that convert mechanical energy from different biomechanical motions into electrical power to drive common electronic devices. The LPPS-NFC-based energy harvesters also endure extreme mechanical deformations (washing, folding, and crumpling) without performance degradation, and maintain stable electrical output up to 5 months, demonstrating their promising potential for use as smart textiles and wearable power sources.

15.
Sci Adv ; 7(29)2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34261658

RESUMO

We rationally synthesized the thermoplastic and hydrophilic poly(urethane-acrylate) (HPUA) binder for a type of printable and stretchable Ag flakes-HPUA (Ag-HPUA) electrodes in which the conductivity can be enhanced by human sweat. In the presence of human sweat, the synergistic effect of Cl- and lactic acid enables the partial removal of insulating surfactant on silver flakes and facilitates sintering of the exposed silver flakes, thus the resistance of Ag-HPUA electrodes can be notably reduced in both relaxed and stretched state. The on-body data show that the resistance of one electrode has been decreased from 3.02 to 0.62 ohm during the subject's 27-min sweating activity. A stretchable textile sweat-activated battery using Ag-HPUA electrodes as current collectors and human sweat as the electrolyte was constructed for wearable electronics. The enhanced conductivity of the wearable wiring electrode from the reaction with sweat would provide meritorious insight into the design of wearable devices.

16.
Int J Mol Sci ; 22(12)2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34208563

RESUMO

Bone exhibits piezoelectric properties. Thus, electrical stimulations such as pulsed electromagnetic fields (PEMFs) and stimuli-responsive piezoelectric properties of scaffolds have been investigated separately to evaluate their efficacy in supporting osteogenesis. However, current understanding of cells responding under the combined influence of PEMF and piezoelectric properties in scaffolds is still lacking. Therefore, in this study, we fabricated piezoelectric scaffolds by functionalization of polycaprolactone-tricalcium phosphate (PCL-TCP) films with a polyvinylidene fluoride (PVDF) coating that is self-polarized by a modified breath-figure technique. The osteoinductive properties of these PVDF-coated PCL-TCP films on MC3T3-E1 cells were studied under the stimulation of PEMF. Piezoelectric and ferroelectric characterization demonstrated that scaffolds with piezoelectric coefficient d33 = -1.2 pC/N were obtained at a powder dissolution temperature of 100 °C and coating relative humidity (RH) of 56%. DNA quantification showed that cell proliferation was significantly enhanced by PEMF as low as 0.6 mT and 50 Hz. Hydroxyapatite staining showed that cell mineralization was significantly enhanced by incorporation of PVDF coating. Gene expression study showed that the combination of PEMF and PVDF coating promoted late osteogenic gene expression marker most significantly. Collectively, our results suggest that the synergistic effects of PEMF and piezoelectric scaffolds on osteogenesis provide a promising alternative strategy for electrically augmented osteoinduction. The piezoelectric response of PVDF by PEMF, which could provide mechanical strain, is particularly interesting as it could deliver local mechanical stimulation to osteogenic cells using PEMF.


Assuntos
Fosfatos de Cálcio , Materiais Revestidos Biocompatíveis , Campos Eletromagnéticos , Osteogênese , Poliésteres , Polivinil , Alicerces Teciduais , Regeneração Óssea , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Materiais Revestidos Biocompatíveis/química , Expressão Gênica , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Osteogênese/efeitos da radiação , Poliésteres/química , Poliésteres/farmacologia , Polivinil/química , Solventes , Engenharia Tecidual , Difração de Raios X
17.
Antioxidants (Basel) ; 10(3)2021 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-33804703

RESUMO

Oxidative stress has been suggested as an important factor in the progress of sarcopenia. The current treatments for sarcopenia have the disadvantages of insufficient effect or daily administration. Therefore, an alternative for effective, safety and long-term treatment may be a solution for unmet needs. Bletilla striata polysaccharide has been reported to have anti-oxidative and anti-inflammatory properties. In this study, we used Bletilla striata polysaccharide (BSP) combined with hydroxyapatite, a carrier. We hypothesized that the resulting combination (BSP-HAP) is a good formula for the controlled release of BSP via intramuscular (IM) administration, so as to prevent the worsening of presarcopenia or even recover from the early stage of the illness. In this research, BSP-HAP was synthesized by a modified low temperature co-precipitation process that would be beneficial for BSP loading. By conducting DCFDA, WST-1 and the Live/Dead assay, BSP-HAP is shown to be a biocompatible material which may release BSP by cells through the endocytosis pathway. Animal studies revealed that the rats treated with BSP-HAP could effectively recover muscle endurance, grip strength or fat/lean mass ratio from lipopolysaccharide (LPS)-induced sarcopenia. This study shows BSP delivered by BSP-HAP system has potential for application in the treatment and prevention of sarcopenia in the future.

18.
Food Res Int ; 142: 110188, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33773664

RESUMO

Ribonucleic acid (RNA) and its degradation products are important functional components widely used in the food industry. Transcription analysis was used to explore the genetic mechanism underlying nucleic acid synthesis in the chemical mutant Saccharomyces cerevisiae strain BY23-195 with high nucleic acid content. Results showed that ribosome biogenesis, meiosis, RNA transport, mitogen-activated protein kinase (MAPK) signaling pathway, tryptophan metabolism, carbon metabolism, and longevity regulating pathway are closely related to the high nucleic acid metabolism of S. cerevisiae. Fourteen most promising genes were selected to evaluate the effect of single-gene deletion or overexpression on the RNA synthesis of S. cerevisiae. Compared with the RNA content of the parent strain BY23, that of mutant strains BY23-HXT1, BY23-ΔGSP2 and BY23-ΔCTT1 increased by 8.19%, 11.60% and 14.00%, respectively. The possible reason why HXT1, GSP2, and CTT1 affect RNA content is by regulating cell fitness. This work was the first to report that regulating the transcription of HXT1, GSP2, and CTT1 could increase the RNA content of S. cerevisiae. This work also provides valuable knowledge on the genetic mechanism of high nucleic acid synthesis in S. cerevisiae and new strategies for increasing its RNA content.


Assuntos
Ácidos Nucleicos , Proteínas de Saccharomyces cerevisiae , Proteínas Quinases Ativadas por Mitógeno , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Transcriptoma
19.
ACS Appl Mater Interfaces ; 13(1): 1222-1233, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33356112

RESUMO

Two-dimensional (2D) mesoporous materials have received substantial research interest due to their highly exposed active sites and unusual nanoconfinement effect. However, controllable and efficient synthesis of 2D mesoporous materials and investigation of their intrinsic properties have remained quite rare. Herein, a general and effective surface-limited cooperative assembly (SLCA) method enabled by leveling precursor solutions on KCl crystals via centrifugation is employed to conveniently synthesize two-dimensional (2D) monolayer mesoporous materials with different compositions. This novel strategy is performed in a manner similar to spin coating, not only enabling generation of ultrathin mesostructured composite film on KCl particles and recycling excessive precursor solution but also providing favorable solvent annealing environment for the film to form ordered mesostructures. Taking monolayer mesoporous Ce0.8Zr0.2O2 solid solutions as a sample, they display ultrathin nanosheet morphology with a thickness of ∼20 nm, highly open porous structure, and easily accessible active sites of surface superoxide species. Upon decoration of 2D mesoporous Ce0.8Zr0.2O2 nanosheets with Pt nanoparticles, the obtained catalyst exhibits superior catalytic activity and stability toward CO oxidation with a low onset temperature of 30 °C and a 100% conversion temperature of 95 °C, which are 35-70 °C lower than those for their counterpart materials, namely, three-dimensional (3D) mesoporous Pt/Ce0.8Zr0.2O2. Moreover, their TOFPt value is ∼11.3 times higher than that of 3D mesoporous Pt/Ce0.8Zr0.2O2. Characterizations based on various techniques indicate that such an outstanding catalytic performance is due to the ultrashort distance (20 nm) of mass diffusion, highly exposed active sites, rich surface-chemisorbed oxygen, and the synergistic effect between the Ce0.8Zr0.2O2 matrix and Pt species.

20.
Sensors (Basel) ; 20(23)2020 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-33255882

RESUMO

With the rapid development of wearable electronic systems, the need for stretchable nanogenerators becomes increasingly important for autonomous applications such as the Internet-of-Things. Piezoelectric nanogenerators are of interest for their ability to harvest mechanical energy from the environment with its inherent polarization arising from crystal structures or molecular arrangements of the piezoelectric materials. In this work, 3D printing is used to fabricate a stretchable piezoelectric nanogenerator which can serve as a self-powered sensor based on synthesized oxide-polymer composites.

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