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1.
Opt Express ; 31(17): 28200-28211, 2023 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-37710880

RESUMEN

Self-powered solar-blind photodetectors (PDs) are promising for military and civilian applications owing to convenient operation, easy preparation, and weak-light sensitivity. In the present study, the solar-blind deep-ultraviolet (DUV) photodetector based on amorphous Ga2O3 (a-Ga2O3) and with a simple vertical stack structure is proposed by applying the low-cost magnetron sputtering technology. By tuning the thickness of the amorphous Ga2O3 layer, the device exhibits excellent detection performance. Under 3 V reverse bias, the photodetector achieves a high responsivity of 671A/W, a high detectivity of 2.21 × 1015 Jones, and a fast response time of 27/11 ms. More extraordinary, with the help of the built-in electric field at the interface, the device achieves an excellent performance in detection when self-powered, with an ultrahigh responsivity of 3.69 A/W and a fast response time of 2.6/6.6 ms under 254 nm light illumination. These results demonstrate its superior performance to most of the self-powered Schottky junction UV photodetectors reported to date. Finally, the Pt/a-Ga2O3/ITO Schottky junction photodiode detector is verified as a good performer in imaging, indicating its applicability in such fields as artificial intelligence, machine vision, and solar-blind imaging.

2.
Nano Lett ; 19(10): 7443-7448, 2019 10 09.
Artículo en Inglés | MEDLINE | ID: mdl-31536705

RESUMEN

Electrochemical actuators are devices that convert electrical energy into mechanical energy via electrochemical processes. They are used in soft robotics, artificial muscles, micropumps, sensors, and other fields. The design of flexible and stable electrode materials remains a major challenge. MXenes, an emerging family of 2D materials, have found applications in energy storage. Here, we report an actuator device using MXene (Ti3C2Tx) as a flexible electrode material. The electrode in 1 M H2SO4 electrolyte exhibits a curvature change up to 0.083 mm-1 and strain of 0.29%. Meanwhile, the MXene-based actuator with a symmetric configuration separated by gel electrolyte (PVA-H2SO4) has curvature and strain changes up to 0.038 mm-1 and 0.26% with excellent retention after 10,000 cycles. In situ X-ray diffraction analysis demonstrates that the actuation mechanism is due to the expansion and shrinkage of the interlayer spacing of MXenes. This research shows promise of this new family of materials for electrochemical actuators.

3.
New Phytol ; 204(4): 1028-40, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25117915

RESUMEN

Natural selection is thought to be a driving force that can cause the evolution of reproductive isolation. The genus Aquilegia is a model system to address how natural selection promotes the process of speciation. Morphological differences between A. oxysepala, A. japonica and their hybrids were quantified for two vegetative (plant height and leaf area) and three floral morphological (sepal area, corolla length and diameter) traits. We also evaluated the genetic variability of the two species and their hybrids based on two chloroplast (1225 bp), four nuclear (5811 bp) genes and 15 microsatellites. Our results revealed that differentiation of A. japonica and A. oxysepala at the ecological and morphological levels also involved divergence at the genetic level. In addition, the analysis of nucleotide variation patterns showed that the two species possessed numerous fixation sites at nuclear genes gAA4, gA7 and gAA12. Furthermore, we found that all of the phenotypic hybrids also showed a genetically admixed ancestry. These findings suggest that natural selection has indeed facilitated the formation of distinct genetic variation patterns in the two Aquilegia species and habitat adaptation has been driving the ecologically based evolution of reproductive isolation.


Asunto(s)
Aquilegia/genética , Especiación Genética , Variación Genética , Aquilegia/fisiología , Quimera , China , ADN de Cloroplastos , Ecosistema , Flores/anatomía & histología , Flores/genética , Flores/fisiología , Flujo Génico , Genética de Población , Haplotipos , Repeticiones de Microsatélite , Datos de Secuencia Molecular , Fenotipo , Filogenia , Aislamiento Reproductivo , Selección Genética
4.
Adv Sci (Weinh) ; : e2407822, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39344716

RESUMEN

Underwater imaging technology plays a pivotal role in marine exploration and reconnaissance, necessitating photodetectors (PDs) with high responsivity, fast response speed, and low preparation costs. This study presents the synergistic optimization of responsivity and response speed in self-powered photoelectrochemical (PEC)-type photodetector arrays based on oxygen-vacancy-tuned amorphous gallium oxide (a-Ga2O3) thin films, specifically designed for solar-blind underwater detection. Utilizing a low-cost one-step sputtering process with controlled oxygen flow, a-Ga2O3 thin films with varying oxygen vacancy (VO) concentrations are fabricated. By balancing the trade-offs among electrocatalytic reactions, charge transfer, carrier recombination, and trapping, both the responsivity and response speed of a-Ga2O3-based self-powered PEC-PDs are simultaneously improved. Consequently, the optimized PEC-PDs demonstrated exceptional performance, achieving a responsivity of 33.75 mA W-1 and response times of 12.8 ms (rise) and 31.3 ms (decay), outperforming the vast majority of similar devices. Furthermore, a pronounced positive correlation between anomalous transient photocurrent spikes and the concentration of VO defects is observed, offering compelling evidence for VO-mediated indirect recombination. Finally, the proof-of-concept solar-blind underwater imaging system, utilizing an array of self-powered PEC-PDs, demonstrated clear imaging capabilities in seawater. This work provides valuable insight into the potential for developing cost-effective, high-performance a-Ga2O3 thin-film-based PEC-PDs for advanced underwater imaging technology.

5.
Chemosphere ; 292: 133469, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34973244

RESUMEN

With the increasing complexity of water environment pollution, it is becoming ever more practical to study the simultaneous removal of multiple pollutants in water. Electrochemical advanced oxidation technology is considered to be one of the most promising green approaches for the degradation of organic pollutants. Herein, Ti3+ and oxygen vacancies (VO) self-doped TiO2-x nanotube array electrodes are employed to investigate the simultaneous degradation and an energy consumption assessment for the effective removal of the antibiotics tetracycline (TC) and metronidazole (MNZ). The electrocatalytic performance of the nanotube arrays prepared at different reduction times is significantly different. The electrochemical reduction of TiO2 nanotube arrays for 10 min presents the best degradation performance for TC and MNZ. When a mixed solution of TC and MNZ is simultaneously degraded, the removal rate of TC (50 mg L-1) and MNZ (50 mg L-1) within 3 h reaches 100%, while the chemical oxygen demand (COD) removal rate is 79.1%. The energy consumption is significantly reduced compared to the degradation of a single substance. Simultaneously, the current utilization rate of the electrochemical degradation system is also significantly improved, with a specific energy consumption of only 85.78 kWh kg-1 and an average current efficiency that can reach 20.2%.


Asunto(s)
Metronidazol , Contaminantes Químicos del Agua , Antibacterianos , Electrodos , Oxidación-Reducción , Tetraciclina , Titanio , Contaminantes Químicos del Agua/análisis
6.
Am J Bot ; 98(8): e213-5, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21821583

RESUMEN

PREMISE OF THE STUDY: The goal of this study was to identify genomic and expressed sequence tag (EST)-derived microsatellite markers from the species Aquilegia flabellata and assess their transferability in A. oxysepala. METHODS AND RESULTS: Eleven genomic and nine EST-derived microsatellite loci were characterized in A. flabellata. These microsatellite primers amplified 66 alleles in all 20 loci. The observed heterozygosity (H(O)) for each population ranged from 0.00 to 0.94. CONCLUSIONS: All of the 20 loci were successfully amplified in A. oxysepala. These genomic and EST-derived microsatellite markers will be useful in further genetic structure, speciation, and adaptive evolution studies.


Asunto(s)
Aquilegia/genética , Etiquetas de Secuencia Expresada/metabolismo , Genoma de Planta , Repeticiones de Microsatélite , Alelos , Aquilegia/metabolismo , Cartilla de ADN/genética , ADN de Plantas/análisis , ADN de Plantas/genética , Frecuencia de los Genes , Tamización de Portadores Genéticos/métodos , Sitios Genéticos , Polimorfismo Genético , Especificidad de la Especie
7.
J Hazard Mater ; 414: 125600, 2021 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-34030425

RESUMEN

Element-doped TiO2 nanotube arrays (TNAs) with optimized active sites provide an effective approach for significantly improving electrocatalytic performance. The challenges in such construction mainly include selection of green dopant and control of active sites. Herein, we present phytic acid as a phosphorus source for P-doped TNAs. An oxygen vacancy (Ov) and P co-doped TNAs (P-TiO2-y) was prepared as an electrochemical oxidation anode. P-TiO2-y exhibits excellent degradation activity due to the formation of Ti-O-P bonds and generation of Ov. P-doping was beneficial in improving the oxygen evolution potential of the electrode, which would be benefit for electrocatalytic degradation of pollutants. Using the P-TiO2-y anode with a current density of 10 mA/cm2 for tetracycline degradation, after a 3 h treatment, the removal rate, chemical oxygen demand and total organic carbon removal rates were 100%, 90.32% and 76.60%, respectively. The P-TiO2-y also has excellent degradation performance for phenol, hydroquinone, p-nitrophenol and metronidazole.

8.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(4): 1175-1180, 2021 Aug.
Artículo en Zh | MEDLINE | ID: mdl-34362499

RESUMEN

OBJECTIVE: To investigate the clinical efficacy of high dose methotrexate (HD-MTX), temozolomide (TMZ), and rituximab (R) in the treatment of patients with primary central nervous system lymphoma (PCNSL). METHODS: Clinical data of patients with PCNSL diagnosed and treated in Guangdong Provincial People's Hospital from February 2010 to May 2017 were collected. First, patients were given 6-8 cycles of MTX (3.5 g/m2) for induction treatment, and then 12 cycles of TMZ (150 mg/m2) for maintenance treatment. The day before induction treatment, patients were given rituximab 375 mg/m2 according to their economic status. A retrospective cohort study was performed on patients receiving HD-MTX+TMZ or HD-MTX+TMZ+R to analyze the efficacy and survival. RESULTS: There were 42 patients enrolled in the study, 17 cases in HD-MTX+TMZ group and 25 cases in HD-MTX+TMZ+R group. The median PFS and OS times in HD-MTX+TMZ+R group were 56.7 months and N/A, respectively, while, 7.3 months and 34.7 months in HD-MTX+TMZ group, respectively. In addition, there was no significant difference in median survival between patients who received TMZ maintenance therapy and those who were only actively monitored. During the induction period, all the patients had grade 1-2 nausea and vomiting, while in the consolidation treatment period, no grade 3/4 toxicity was observed. CONCLUSION: The combination of HD-MTX+TMZ+R in the treatment of PCNSL patients shows a definite short-term effect, which can increase the survival rate of the patients. The side effects are mild, and the patients can generally tolerate.


Asunto(s)
Neoplasias del Sistema Nervioso Central , Linfoma no Hodgkin , Protocolos de Quimioterapia Combinada Antineoplásica , Sistema Nervioso Central , Neoplasias del Sistema Nervioso Central/tratamiento farmacológico , Humanos , Linfoma no Hodgkin/tratamiento farmacológico , Metotrexato/uso terapéutico , Estudios Retrospectivos , Rituximab/uso terapéutico , Temozolomida/uso terapéutico , Resultado del Tratamiento
9.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 27(6): 1298-302, 2010 Dec.
Artículo en Zh | MEDLINE | ID: mdl-21374982

RESUMEN

This study was designed to assess the effect of implantation site and environment on early in vivo degradation behaviors of poly(L-lactide) (PLLA) and poly(L-lactide-co-glycolide) (PLGA) copolymer. The rods were implanted at two sites in each of 24 New Zealand White rabbits. The first site was within the suprapatellar bursa of the joint cavities (JC) and the second site was in the opposite condyles of femurs (CF). Three rabbits of each group underwent explantation of rods after 4, 8, 12, and 16 weeks. At each interval, measures were taken to evaluate the molecular weight, shear strength, weight loss and thermal properties of PLLA and PLGA. It was found that PLGA degraded slightly faster than PLLA. After 16 weeks, PLLA's initial inherent viscosity of 4.6 decreased to about 3.4 in both implantation sites while that of PLGA decreased from 4.6 to about 2.2. Both PLGA and PLLA showed enough shear strength retention in 16 weeks (> or = 53MPa) within 16 weeks. Autocatalysis mechanism was confirmed by the fact of accelerated weight loss of PLGA after 8 weeks and of PLLA after 12 weeks. The results revealed that PLGA could be a promising candidate material as a replacement of PLLA in internal fixation of bone fractures, and no significant difference of early in vivo degradation behaviors between PLLA and PLGA was observed in regard to different implantation sites in 16 weeks.


Asunto(s)
Implantes Absorbibles , Implantes Experimentales , Fijadores Internos , Ácido Láctico/metabolismo , Ácido Poliglicólico/metabolismo , Polímeros/metabolismo , Animales , Clavos Ortopédicos , Femenino , Ácido Láctico/química , Masculino , Poliésteres , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Polímeros/química , Conejos
10.
Sci Total Environ ; 742: 140622, 2020 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-32721742

RESUMEN

A novel electrochemical nitrite (NaNO2) sensor was fabricated by combining nanosilver with protonated carbon nitride (H-C3N4) supported on carbon cloth (CC). H-C3N4 was distributed uniformly on the CC surface, providing more active sites for the electrocatalytic active center (nanosilver). CC as a substrate improved the H-C3N4 conductivity and provided the sensor with a flexible feature. The strong synergistic effect between CC, H-C3N4, and nanosilver can exert a significant electrocatalytic performance on the flexible sensor. The Ag/H-C3N4/CC flexible sensor electrode did not consume much more time to polish the surface of traditional electrodes, and possessed a high sensitivity of 0.85537 µA/mg, a wide linear response range that spanned 5 to 1000 µM, a low detection limit of 0.216 µM (S/N = 3), and high selectivity for nitrite in the presence of common organic and inorganic interfering species (such as CaCl2, NaCl, MgCl2, NaNO3, glucose, urea, and p-nitrophenol). The Ag/H-C3N4/CC flexible sensor can be used for sample detection of nitrite as it has a strong anti-interference ability, good reproducibility, repeatability, and long-term stability. The Ag/H-C3N4/CC sensor is a promising alternative electrode to traditional ones such as ITO, gold or glassy carbon electrodes.

11.
Biomater Sci ; 8(5): 1290-1297, 2020 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-31899467

RESUMEN

Primary central nervous system lymphoma (PCNSL) is a rare brain tumor. Its therapeutic efficacy is much lower than that of traditional lymphoma, largely due to the presence of the blood-brain barrier (BBB), which hinders the effective drug delivery and deposition on the disease site. Angiopep-2 (ANG) can target low-density lipoprotein receptor-related protein (LRP) on the surface of brain capillary endothelial cells (BCECs) and exhibits high BBB transport capability. In this study, we designed an ANG conjugated poly(ethylene glycol)-b-poly(ε-caprolactone) (PEG-b-PCL) (APP) nanoparticle to deliver doxorubicin (DOX) for the treatment of PCNSL. Our data indicated that the targeted APP nanoparticles showed significantly increased cellular uptake by BCECs compared with the control nanoparticles. In the intracranial SU-DHL-2-LUC lymphoma xenograft mice model, APP enhanced drug deposition in tumor tissues, and DOX-loaded APP (APP@DOX) exhibited a better therapeutic effect than free DOX and nontargeted PP@DOX, which significantly prolonged the survival time of mice.


Asunto(s)
Antibióticos Antineoplásicos/farmacología , Neoplasias del Sistema Nervioso Central/tratamiento farmacológico , Doxorrubicina/farmacología , Linfoma/tratamiento farmacológico , Nanopartículas/química , Péptidos/química , Animales , Antibióticos Antineoplásicos/síntesis química , Antibióticos Antineoplásicos/química , Barrera Hematoencefálica/efectos de los fármacos , Línea Celular , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Neoplasias del Sistema Nervioso Central/metabolismo , Neoplasias del Sistema Nervioso Central/patología , Modelos Animales de Enfermedad , Doxorrubicina/síntesis química , Doxorrubicina/química , Portadores de Fármacos/química , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Lactonas/química , Linfoma/metabolismo , Linfoma/patología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Neoplasias Experimentales/tratamiento farmacológico , Neoplasias Experimentales/metabolismo , Neoplasias Experimentales/patología , Polietilenglicoles/química
12.
J Biomed Mater Res A ; 100(11): 2897-904, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22696182

RESUMEN

Control of cellular responses is crucial for the use of electrospun membranes in biomedical applications, including tissue engineering or biomedical devices. However, it is still unclear whether adhesion and proliferation of fibroblasts is stimulated or inhibited on polyethylene glycol (PEG)-modified electrospun membranes. In this study, poly(L-lactide-co-glycolide) (PLLGA)-PEG copolymer and pure PEG were blended with PLLGA, and then electrospun onto nonwoven membranes. The effects of blending of PLLGA-PEG or pure PEG on the adsorption of proteins, and further on the adhesion and proliferation of L929 fibroblasts on the electrospun membranes were investigated. Addition of PLLGA-PEG or PEG significantly improved the hydrophilicity of the electrospun membranes. Pure PEG had no obvious effects on the growth of L929 fibroblasts; in contrast, PLLGA-PEG significantly inhibited the adsorption of proteins and the proliferations of the cells on the electrospun membranes. In response to diminished protein adsorption, mRNA expression of genes related to cell adhesion and migration was up-regulated. The limited effects of pure PEG were probably caused by its preferential dissolution, whereas membrane-confined PLLGA-PEG displayed excellent performance on the inhibition of protein adsorption and cell proliferation.


Asunto(s)
Materiales Biocompatibles/química , Fibroblastos/citología , Membranas Artificiales , Polietilenglicoles/química , Poliglactina 910/química , Animales , Adhesión Celular , Línea Celular , Proliferación Celular , Fibroblastos/metabolismo , Regulación de la Expresión Génica , Ensayo de Materiales , Ratones , Humectabilidad
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