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1.
Nat Methods ; 20(7): 1029-1036, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37231266

RESUMEN

As a miniature RNA-guided endonuclease, IscB is presumed to be the ancestor of Cas9 and to share similar functions. IscB is less than half the size of Cas9 and thus more suitable for in vivo delivery. However, the poor editing efficiency of IscB in eukaryotic cells limits its in vivo applications. Here we describe the engineering of OgeuIscB and its corresponding ωRNA to develop an IscB system that is highly efficient in mammalian systems, named enIscB. By fusing enIscB with T5 exonuclease (T5E), we found enIscB-T5E exhibited comparable targeting efficiency to SpG Cas9 while showing reduced chromosome translocation effects in human cells. Furthermore, by fusing cytosine or adenosine deaminase with enIscB nickase, we generated miniature IscB-derived base editors (miBEs), exhibiting robust editing efficiency (up to 92%) to induce DNA base conversions. Overall, our work establishes enIscB-T5E and miBEs as versatile tools for genome editing.


Asunto(s)
Sistemas CRISPR-Cas , Desoxirribonucleasa I , Animales , Humanos , Desoxirribonucleasa I/genética , Desoxirribonucleasa I/metabolismo , Edición Génica , Citosina , ARN/genética , Mamíferos/genética , Mamíferos/metabolismo
2.
Cell Mol Biol (Noisy-le-grand) ; 70(4): 152-157, 2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38678612

RESUMEN

The purpose of this study was to explore the effects of regulatory B-cells (Breg) on intracranial aneurysms by mediating IL-1ß/IL-1R pathways.  The study involved 60 patients undergoing angiography in a hospital from January to June 2022, divided into two groups: 30 with intracranial aneurysms (observation group) and 30 without (control group). Researchers extracted peripheral blood mononuclear cells (PBMC) to analyze the proportion of CD19+CD24hiCD38hiB cells using flow cytometry. These cells, along with T-cells and regulatory T-cells (Treg), were isolated through magnetic bead cell sorting. Following co-culture, the proliferation of T-cells and their related secretory factors were assessed. Additionally, Breg cells, treated with an IL-1R receptor blocker or IL-1R expression adenovirus, were studied to evaluate the levels of IL-10 and TGF-ß. In the study, the observation group showed lower levels of CD19+CD24hiCD38hiB cells, IL-10, and TGF-ß in PBMC than the control group (P<0.05). T-cell proportions were similar in both groups pre and post co-culture (P>0.05). Post co-culture, IFN-γ decreased while IL-4 increased in both groups. The observation group had higher IFN-γ and lower IL-4 than the control group (P<0.05). TNF-α in CD8+T cells, and granzyme B and perforin mRNA levels decreased post co-culture but were higher in the observation group (P<0.05). IL-10 and TGF-ß in Treg cells increased in both groups post co-culture but were lower in the observation group (P<0.05). The observation group also had fewer CD19+IL-1R+IL-10+B cells (P<0.05). After IL-1R blocker addition, IL-10 and TGF-ß in the supernatant decreased in the observation group (P<0.05). Following transfection, IL-1 and TGF-ß levels increased compared to the blank group (P<0.05). The function of peripheral blood CD19+CD24hiCD38hiB cells is impaired in patients with intracranial aneurysms, which may be related to IL-1ß/IL-1R pathways disorder.


Asunto(s)
Linfocitos B Reguladores , Interleucina-1beta , Aneurisma Intracraneal , Receptores de Interleucina-1 , Femenino , Humanos , Masculino , Linfocitos B Reguladores/inmunología , Linfocitos B Reguladores/metabolismo , Proliferación Celular , Técnicas de Cocultivo , Interleucina-10/metabolismo , Interleucina-1beta/metabolismo , Aneurisma Intracraneal/inmunología , Aneurisma Intracraneal/patología , Aneurisma Intracraneal/metabolismo , Leucocitos Mononucleares/metabolismo , Leucocitos Mononucleares/inmunología , Receptores de Interleucina-1/metabolismo , Receptores de Interleucina-1/genética , Transducción de Señal , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Factor de Crecimiento Transformador beta/metabolismo
3.
Phys Chem Chem Phys ; 26(7): 6420-6428, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38317611

RESUMEN

Recently, thermally activated delayed fluorescence (TADF) molecules with through-space charge transfer (TSCT) features have been widely applied in developing organic light-emitting diodes with high luminescence efficiencies. The performance of TSCT-TADF molecules depends highly on their molecular structures. Therefore, theoretical investigation plays a significant role in designing novel highly efficient TSCT-TADF molecules. Herein, we theoretically investigate two recently reported TSCT-TADF molecules, 1'-(2,12-di-t-butyl[1,4]benzoxaborinino[2,3,4-kl]phenoxaborinin-7-yl)-10-phenyl-10H-spiro[acridine-9,9'-fluorene] (AC-BO) and 1-(2,12-di-t-butyl[1,4]benzoxaborinino[2,3,4-kl]phenoxaborinin-7-yl)-9',9'-dimethyl-9'H-spiro [fluorene-9,5'-quinolino[3,2,1-de]acridine](QAC-BO). The calculated photophysical properties (e.g. excited state energy levels and luminescence properties) for these two compounds are in good agreement with experimental data. Based on the systematic analysis of structure-performance relationships, we design three novel TSCT-TADF molecules with high molecular rigidity and evident TSCT features, i.e., DQAC-DBO, DQAC-SBO, and DQAC-NBO. They exhibit deep-blue light emissions and fast reverse intersystem crossing rates (KRISCs). Our calculations demonstrate that the nearly coplanar orientation of the donor and acceptor is critical to achieve remarkable KRISCs and fluorescence efficiencies in TSCT-TADF molecules.

4.
J Phys Chem A ; 128(9): 1611-1619, 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38382059

RESUMEN

Thermally activated delayed fluorescence (TADF) emitters based on the triptycene skeleton demonstrate exceptional performance, superior stability, and low efficiency roll-off. Understanding the interplay between the luminescent properties of triptycene-TADF molecules and their assembly environments, along with their excited-state characteristics, necessitates a comprehensive theoretical exploration. Herein, we predict the photophysical properties of triptycene-TADF molecules in a thin film environment using the quantum mechanics/molecular mechanics method and quantify their substantial dependency on the heavy atom effects and reorganization energies using the Marcus-Levich theory. Our calculated photophysical properties for two recently reported molecules closely align with experimental values. We design three novel triptycene-TADF molecules by incorporating chalcogen elements (O, S, and Se) to modify the acceptor units. These newly designed molecules exhibit reduced reorganization energies and enhanced reverse intersystem crossing (RISC) rates. The heavy atom effect amplifies spin-orbit coupling, thereby facilitating the RISC process, particularly at a remarkably high rate of ∼109 s-1.

5.
Phys Chem Chem Phys ; 25(16): 11484-11492, 2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37039011

RESUMEN

Developing novel lead-free perovskite materials with suitable bandgaps and superior thermal stability is crucial to boost their applications in next-generation photovoltaic technologies. High throughput screening combined with the first principles method can accurately and effectively screen out promising perovskites. Herein, we select two lead-free all-inorganic halide double perovskite materials Cs2KMI6 (M = Ga, In) from 1026 compounds with the criteria including appropriate structure factors, positive decomposition energies, and suitable direct bandgaps. We investigated the thermal and mechanical stability, geometric and electronic structures, photoelectric properties, and defect formation energies for both perovskites Cs2KMI6 (M = Ga, In). They can exhibit excellent structural formability and stability through the analysis of structure factors, elastic constants, and stable chemical potential regions. In addition, we investigate the defect effects of Cs2KMI6 (M = Ga, In) on the photovoltaic performance by evaluating the defect formation energies and transition energy levels. Based on the HSE06 functional, we calculated the energy band structures of these two compounds and demonstrate the direct bandgaps of 1.69 eV (HSE06) and 2.16 eV (HSE06) for Cs2KGaI6 and Cs2KInI6, respectively. Moreover, we predicted excellent spectroscopic limited maximum efficiencies (SLMEs) of these two perovskites with high light absorption coefficients (around 105 cm-1), for instance, the SLME of Cs2KGaI6 can reach as high as 28.39%.

6.
Nanotechnology ; 29(12): 125702, 2018 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-29350192

RESUMEN

The mechanical properties of size-dependent nanowires are important in nano-electro-mechanical systems (NEMSs), and have attracted much research interest. Characterization of the size effect of nanowires in atmosphere directly to broaden their practical application instead of just in high vacuum situations, as reported previously, is desperately needed. In this study, we systematically studied the Young's modulus of vertical ZnO nanowires in atmosphere. The diameters ranged from 48 nm to 239 nm with a resonance method using non-contact atomic force microscopy. The values of Young's modulus in atmosphere present extremely strong increasing tendency with decreasing diameter of nanowire due to stronger surface atomic bonds compared with that in vacuum. A core-shell model for nanowires is proposed to explore the Young's modulus enhancement in atmosphere, which is correlated with atoms of oxygen occurring near the nanowire surface. The modified model is more accurate for analyzing the mechanical behavior of nanowires in atmosphere compared with the model in vacuum. Furthermore, it is possible to use this characterization method to measure the size-related elastic properties of similar wire-sharp nanomaterials in atmosphere and estimate the corresponding mechanical behavior. The study of the size-dependent Young's modulus in ZnO nanowires in atmosphere will improve the understanding of the mechanical properties of nanomaterials as well as providing guidance for applications in NEMSs, nanogenerators, biosensors and other related areas.

7.
J Plant Res ; 130(4): 723-733, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28378100

RESUMEN

Understanding the mechanism for salt tolerance in wild soybean (Glycine soja) can help researchers improve that trait in cultivated soybean lines. We analyzed the effects of excess NaCl on the growth, physiology, and ion distribution in three soybean species: wild G. soja (W8), semi-wild G. gracilis (SW18), and the cultivated salt-sensitive G. max (cv. Melrose). These comparisons revealed that, under salt stress, shoot and root lengths and biomass (either shoot or root dry weights) were significantly higher for the W8 genotype than for the other two. Most of the morphological parameters for roots from the W8 plants were also increased, including total length, specific root length, and surface area. However, the average root diameter for W8 was significantly lower than that of either SW18 or 'Melrose' soybeans. In response to salinity, photosynthesis was suppressed to a greater extent in 'Melrose' than in W8. The relatively higher tolerance shown by W8 plants was also associated with lower levels of malondialdehyde, hydrogen peroxide, and relative electrical conductivity, but higher activities by superoxide dismutase and peroxidase, as well as more free proline and glycine betaine. In addition, the W8 plants contained less Na+ and Cl-, but more K+, and they had a higher K+/Na+ ratio in their leaves and roots when compared with either SW18 or 'Melrose' plants. Therefore, the W8 genotype performs better in terms of seedling growth, photosynthetic characteristics, and physiological indexes. These findings provide guidance for developing new soybean cultivars with improved tolerance to salt stress. Our data also contribute to the knowledge base for plant salt tolerance as a tool for increasing the yields of other crops in high-salinity soils.


Asunto(s)
Glycine max/fisiología , Cloruro de Sodio/farmacología , Estrés Fisiológico , Productos Agrícolas , Peróxido de Hidrógeno/metabolismo , Malondialdehído/metabolismo , Fotosíntesis , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/fisiología , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/fisiología , Salinidad , Tolerancia a la Sal , Plantones/efectos de los fármacos , Plantones/crecimiento & desarrollo , Plantones/fisiología , Glycine max/efectos de los fármacos , Glycine max/crecimiento & desarrollo , Superóxido Dismutasa/metabolismo
8.
Rev Invest Clin ; 69(6): 319-328, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29265114

RESUMEN

BACKGROUND: Acute cerebral infarction (ACI) and intracerebral hemorrhage (ICH) are potentially lethal cerebrovascular diseases that seriously impact public health. ACI and ICH share several common clinical manifestations but have totally divergent therapeutic strategies. A poor diagnosis can affect stroke treatment. OBJECTIVE: To screen for biomarkers to differentiate ICH from ACI, we enrolled 129 ACI and 128 ICH patients and 65 healthy individuals as controls. METHODS: Patients with stroke were diagnosed by computed tomography/magnetic resonance imaging, and their blood samples were obtained by fingertip puncture within 2-12 h after stroke initiation. We compared changes in metabolites between ACI and ICH using dried blood spot-based direct infusion mass spectrometry technology for differentiating ICH from ACI. RESULTS: Through multivariate statistical approaches, 11 biomarkers including 3-hydroxylbutyrylcarnitine, glutarylcarnitine (C5DC), myristoylcarnitine, 3-hydroxypalmitoylcarnitine, tyrosine/citrulline (Cit), valine/phenylalanine, C5DC/3-hydroxyisovalerylcarnitine, C5DC/palmitoylcarnitine, hydroxystearoylcarnitine, ratio of sum of C0, C2, C3, C16, and C18:1 to Cit, and propionylcarnitine/methionine were screened. An artificial neural network model was constructed based on these parameters. A training set was evaluated by cross-validation method. The accuracy of this model was checked by an external test set showing a sensitivity of 0.8400 (95% confidence interval [CI], 0.7394-0.9406) and specificity of 0.7692 (95% CI, 0.6536-0.8848). CONCLUSION: This study confirmed that metabolomic analysis is a promising tool for rapid and timely stroke differentiation and prediction based on differential metabolites.


Asunto(s)
Hemorragia Cerebral/diagnóstico , Infarto Cerebral/diagnóstico , Metabolómica/métodos , Accidente Cerebrovascular/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/metabolismo , Estudios de Casos y Controles , Hemorragia Cerebral/metabolismo , Hemorragia Cerebral/fisiopatología , Infarto Cerebral/metabolismo , Infarto Cerebral/fisiopatología , Diagnóstico Diferencial , Pruebas con Sangre Seca , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Redes Neurales de la Computación , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Accidente Cerebrovascular/metabolismo , Accidente Cerebrovascular/fisiopatología , Tomografía Computarizada por Rayos X/métodos
9.
Nanotechnology ; 27(48): 485402, 2016 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-27819801

RESUMEN

A single-layer zinc oxide (ZnO) nanorod array-based micro energy harvester was designed and integrated with a piezoelectric metacapacitor. The device presents outstanding low-frequency (1-10 Hz) mechanical energy harvesting capabilities. When compared with conventional pristine ZnO nanostructured piezoelectric harvesters or generators, both open-circuit potential and short-circuit current are significantly enhanced (up to 3.1 V and 124 nA cm-2) for a single mechanical knock (∼34 kPa). Higher electromechanical conversion efficiency (1.3 pC/Pa) is also observed. The results indicate that the integration of the piezoelectric metacapacitor is a crucial factor for improving the low-frequency energy harvesting performance. A double piezoelectric-driven mechanism is proposed to explain current higher output power, in which the metacapacitor plays the multiple roles of charge pumping, storing and transferring. An as-fabricated prototype device for lighting an LED demonstrates high power transference capability, with over 95% transference efficiency to the external load.

10.
Biochem Genet ; 54(3): 232-248, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26846709

RESUMEN

In plants, resistance (R) genes are involved in pathogen recognition and subsequent activation of innate immune responses. The nucleotide-binding site-leucine-rich repeat (NBS-LRR) genes family forms the largest R-gene family among plant genomes and play an important role in plant disease resistance. In this paper, comprehensive analysis of NBS-encoding genes is performed in the whole Setaria italica genome. A total of 96 NBS-LRR genes are identified, and comprehensive overview of the NBS-LRR genes is undertaken, including phylogenetic analysis, chromosome locations, conserved motifs of proteins, and gene expression. Based on the domain, these genes are divided into two groups and distributed in all Setaria italica chromosomes. Most NBS-LRR genes are located at the distal tip of the long arms of the chromosomes. Setaria italica NBS-LRR proteins share at least one nucleotide-biding domain and one leucine-rich repeat domain. Our results also show the duplication of NBS-LRR genes in Setaria italica is related to their gene structure.


Asunto(s)
Biología Computacional/métodos , Resistencia a la Enfermedad , Proteínas/genética , Setaria (Planta)/genética , Mapeo Cromosómico , Regulación de la Expresión Génica de las Plantas , Proteínas Repetidas Ricas en Leucina , Familia de Multigenes , Filogenia , Enfermedades de las Plantas/genética , Proteínas de Plantas/genética , Dominios Proteicos , Proteínas/química
11.
Nano Lett ; 15(2): 1128-34, 2015 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-25575294

RESUMEN

A chip-size vertically aligned nanowire (NW) resonator arrays (VNRs) device has been fabricated with simple one-step lithography process by using grown self-assembled zinc oxide (ZnO) NW arrays. VNR has cantilever diameter of 50 nm, which breakthroughs smallest resonator record (>100 nm) functioning in atmosphere. A new atomic displacement sensing method by using atomic force microscopy is developed to effectively identify the resonance of NW resonator with diameter 50 nm in atmosphere. Size-effect and half-dimensional properties of the NW resonator have been systematically studied. Additionally, VNR has been demonstrated with the ability of detecting nanofilm thickness with subnanometer (<10(-9)m) resolution.

12.
J Sci Food Agric ; 96(13): 4484-91, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26858003

RESUMEN

BACKGROUND: Tricholoma mongolicum Imai is a well-known edible and medicinal mushroom which in recent years has attracted increasing attention because of its bioactivities. In this study, water-soluble polysaccharides were extracted from T. mongolicum Imai by cellulase-assisted extraction and their antioxidant activities were investigated. RESULTS: In order to improve the yield of polysaccharides, four variables, cellulase amount (X1 ), pH (X2 ), temperature (X3 ) and extraction time (X4 ), were investigated with a Box-Behnken design. The optimal conditions were predicted to be cellulase amount of 20 g kg(-1) , pH of 4.0, temperature of 50 °C and extraction time of 127 min, with a predicted polysaccharide yield of 190.1 g kg(-1) . The actual yield of polysaccharides under these conditions was 189.6 g kg(-1) , which matched the predicted value well. The crude polysaccharides were purified to obtain four fractions, and characterization of each was carried out. In addition, antioxidant properties of four polysaccharides assessed by 1,1-diphenyl-2-picryldydrazyl (DPPH) and hydroxyl radical-scavenging assays indicated that polysaccharides from T. mongolicum Imai (TMIPs) possessed antioxidant activity in a dose-dependent manner. CONCLUSION: TMIPs show moderate antioxidant activities in vitro. Therefore it is suggested that TMIPs are potential natural antioxidants for use in functional foods. © 2016 Society of Chemical Industry.


Asunto(s)
Antioxidantes/aislamiento & purificación , Celulasa/metabolismo , Mezclas Complejas/aislamiento & purificación , Aditivos Alimentarios/aislamiento & purificación , Cuerpos Fructíferos de los Hongos/química , Polisacáridos Fúngicos/aislamiento & purificación , Tricholoma/química , Algoritmos , Antioxidantes/análisis , Antioxidantes/química , Antioxidantes/metabolismo , Secuencia de Carbohidratos , China , Mezclas Complejas/biosíntesis , Mezclas Complejas/química , Aditivos Alimentarios/análisis , Aditivos Alimentarios/química , Aditivos Alimentarios/metabolismo , Alimentos en Conserva/análisis , Alimentos en Conserva/economía , Depuradores de Radicales Libres/análisis , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/aislamiento & purificación , Depuradores de Radicales Libres/metabolismo , Cuerpos Fructíferos de los Hongos/metabolismo , Polisacáridos Fúngicos/análisis , Polisacáridos Fúngicos/biosíntesis , Polisacáridos Fúngicos/química , Calor , Concentración de Iones de Hidrógeno , Modelos Químicos , Peso Molecular , Estadística como Asunto , Factores de Tiempo , Tricholoma/metabolismo
13.
Phytother Res ; 29(10): 1658-64, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26084208

RESUMEN

Structure-activity relationship for the inhibition of Schisandra chinensis's ingredients toward (Uridine-Diphosphate) UDP-glucuronosyltransferases (UGTs) activity was performed in the present study. In vitro incubation system was employed to screen the inhibition capability of S. chinensis's ingredients, and in silico molecular docking method was carried out to explain possible mechanisms. At 100 µM of compounds, the activity of UGTs was inhibited by less than 90% by schisandrol A, schisandrol B, schisandrin, schisandrin C, schisantherin A, gomisin D, and gomisin G. Schisandrin A exerted strong inhibition toward UGT1A1 and UGT1A3, with the residual activity to be 7.9% and 0% of control activity. Schisanhenol exhibited strong inhibition toward UGT2B7, with the residual activity to be 7.9% of control activity. Gomisin J of 100 µM inhibited 91.8% and 93.1% of activity of UGT1A1 and UGT1A9, respectively. Molecular docking prediction indicated different hydrogen bonds interaction resulted in the different inhibition potential induced by subtle structure alteration among schisandrin A, schisandrin, and schisandrin C toward UGT1A1 and UGT1A3: schisandrin A > schisandrin > schisandrin C. The detailed inhibition kinetic evaluation showed the strong inhibition of gomisin J toward UGT1A9 with the inhibition kinetic parameter (Ki ) to be 0.7 µM. Based on the concentrations of gomisin J in the plasma of the rats given with S. chinensis, high herb-drug interaction existed between S. chinensis and drugs mainly undergoing UGT1A9-mediated metabolism. In conclusion, in silico-in vitro method was used to give the inhibition information and possible inhibition mechanism for S. chinensis's components toward UGTs, which guide the clinical application of S. chinensis.


Asunto(s)
Glucuronosiltransferasa/antagonistas & inhibidores , Extractos Vegetales/farmacología , Schisandra , Animales , Ciclooctanos , Dioxoles , Medicamentos Herbarios Chinos/farmacología , Interacciones de Hierba-Droga , Lignanos , Compuestos Policíclicos , Ratas , Schisandra/química , Relación Estructura-Actividad
14.
Small ; 10(24): 5042-6, 2014 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-25227709

RESUMEN

How properties change as 1D nanomaterials reduce in length to 0D, that is, the properties of 0.5D nanomaterial, are studied via photoelectric changes in ZnO nanowires. The photoelectric property of this 0.5D nanomaterial changes significantly as the 3D nanoconfinement is reinforced. This finding can be expanded to more properties and materials to profoundly impact fields of nanoscience, nanodevices, and nanoelectronics.

15.
Phys Chem Chem Phys ; 16(23): 11297-302, 2014 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-24789217

RESUMEN

We demonstrate a facile technique to assemble solution phase-synthesized bismuth telluride (Bi2Te3) nanoplatelets into arrays of micropatterns. Aminosilane self-assembled monolayers (SAMs) are printed on silicon dioxide (SiO2) substrates using microcontact printing (µCP). The SAM printed surfaces are terminated with amine-groups allowing Bi2Te3 nanoplatelet selective adsorption by electrostatic attraction. Using Kelvin probe force microscopy, the electrical potential difference between aminosilane SAM and Bi2Te3 nanoplatelet surfaces is found to be ∼650 mV, which is larger than that (∼400 mV) between the SiO2 substrate and Bi2Te3 nanoplatelet surfaces. The selective adsorption provides an opportunity for integrating solution phase-grown topological insulators toward several device-level applications.

16.
Nano Lett ; 13(1): 111-5, 2013 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-23205561

RESUMEN

We demonstrate an innovative technique for the direct measurement on the shear modulus of an individual nanorod. This measurement is based on atomic force microscopy (AFM) and microfabrication techniques. A nanorod is first aligned along the edge of a small trench in a silicon substrate, and then one end of the nanorod is fixed on the substrate. When an AFM tip scans over the nanorod in contact mode, the nanorod will be twisted by the comprehensive action from the force of the AFM tip, confinement from the trench edge and the fixing end. The shear deformation and the corresponding force that caused the deformation can be retrieved from topography and lateral force image, respectively. By small-angle approximation, the shear modulus of the ZnO NR, which has a radius of 166 nm and a length of 4 µm, is measured to be 8.1 ± 1.9 GPa. This method can be applied directly to characterize the shear modulus of any nanowire/nanorod that possesses a polygon cross section.

17.
Angew Chem Int Ed Engl ; 53(44): 11935-9, 2014 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-25212514

RESUMEN

Multifunctional glass windows that combine energy storage and electrochromism have been obtained by facile thermal evaporation and electrodeposition methods. For example, WO3 films that had been deposited on fluorine-doped tin oxide (FTO) glass exhibited a high specific capacitance of 639.8 F g(-1). Their color changed from transparent to deep blue with an abrupt decrease in optical transmittance from 91.3% to 15.1% at a wavelength of 633 nm when a voltage of -0.6 V (vs. Ag/AgCl) was applied, demonstrating its excellent energy-storage and electrochromism properties. As a second example, a polyaniline-based pseudocapacitive glass was also developed, and its color can change from green to blue. A large-scale pseudocapacitive WO3-based glass window (15×15 cm(2)) was fabricated as a prototype. Such smart pseudocapacitive glass windows show great potential in functioning as electrochromic windows and concurrently powering electronic devices, such as mobile phones or laptops.

18.
Front Bioeng Biotechnol ; 12: 1270237, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38328442

RESUMEN

As the population ages and the incidence of traumatic events rises, there is a growing trend toward the implantation of devices to replace damaged or degenerated tissues in the body. In orthopedic applications, some implants are equipped with sensors to measure internal data and monitor the status of the implant. In recent years, several multi-functional implants have been developed that the clinician can externally control using a smart device. Experts anticipate that these versatile implants could pave the way for the next-generation of technological advancements. This paper provides an introduction to implantable sensors and is structured into three parts. The first section categorizes existing implantable sensors based on their working principles and provides detailed illustrations with examples. The second section introduces the most common materials used in implantable sensors, divided into rigid and flexible materials according to their properties. The third section is the focal point of this article, with implantable orthopedic sensors being classified as joint, spine, or fracture, based on different practical scenarios. The aim of this review is to introduce various implantable orthopedic sensors, compare their different characteristics, and outline the future direction of their development and application.

19.
Regen Biomater ; 11: rbae047, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38903560

RESUMEN

Development of piezoelectric biomaterials with high piezoelectric performance, while possessing excellent flexibility, biocompatibility, and biodegradability still remains a great challenge. Herein, a flexible, biocompatible and biodegradable piezoelectric ß-glycine-alginate-glycerol (Gly-Alg-Glycerol) film with excellent in vitro and in vivo sensing performance was developed. Remarkably, a single, monolithic ß-glycine spherulite, instead of more commonly observed multiple spherulites, was formed in alginate matrix, thereby resulting in outstanding piezoelectric property, including high piezoelectric constant (7.2 pC/N) and high piezoelectric sensitivity (1.97 mV/kPa). The Gly-Alg-Glycerol film exhibited superior flexibility, enabling complex shape-shifting, e.g. origami pigeon, 40% tensile strain, and repeated bending and folding deformation without fracture. In vitro, the flexible Gly-Alg-Glycerol film sensor could detect subtle pulse signal, sound wave and recognize shear stress applied from different directions. In addition, we have demonstrated that the Gly-Alg-Glycerol film sensor sealed by polylactic acid and beeswax could serve as an in vivo sensor to monitor physiological pressure signals such as heartbeat, respiration and muscle movement. Finally, the Gly-Alg-Glycerol film possessed good biocompatibility, supporting the attachment and proliferation of rat mesenchymal stromal cells, and biodegradability, thereby showing great potential as biodegradable piezoelectric biomaterials for biomedical sensing applications.

20.
Int J Food Microbiol ; 411: 110551, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38171235

RESUMEN

Nanomaterials are widely investigated in sustainable agriculture owing to their unique physicochemical properties, especially Cu-based nanomaterial with eco-friendliness and essential for plant. However, the effect of CuO nanomaterial on Bipolaris sorokiniana (B. sorokiniana) is yet to be systematically understood. In this study, a three-dimension hierarchical structure CuO nanoflower (CuO NF) with ultrathin petals and excellent dispersibility in water was constructed and proved to have outstanding antifungal activity against B. sorokiniana with the inhibition rate of 86 % in mycelial growth, 74 % in mycelial dry weight and 75 % in conidial germination. Furthermore, the antifungal mechanism was assigned to the production of reactive oxygen species in intracellular caused by antioxidant mimicking activity of CuO NF to damage of cell membrane integrity and result cellular leakage. Additionally, the good control effect of CuO NF on wheat diseases caused by B. sorokiniana was demonstrated through pot experiment. This article firstly reveals the antifungal activity and mechanism of CuO NF on B. sorokiniana, and establishes the relationship between enzyme-like activity of CuO NF and its antifungal activity, which provides a promising application of Cu-based nanomaterial as nanofungicide in plant protection and a theoretical foundation for structure design of nanomaterials to improve their antifungal activities.


Asunto(s)
Ascomicetos , Nanoestructuras , Antifúngicos/farmacología , Antifúngicos/metabolismo , Nanoestructuras/química
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