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1.
Adv Mater ; 35(32): e2301787, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37204145

RESUMO

Tailoring light-matter interactions via plasmonic nanoantennas (PNAs) has emerged as a breakthrough technology for spectroscopic applications. The detuning between molecular vibrations and plasmonic resonances, as a fundamental and inevitable optical phenomenon in light-matter interactions, reduces the interaction efficiency, resulting in a weak molecule sensing signal at the strong detuning state. Here, it is demonstrated that the low interaction efficiency from detuning can be tackled by overcoupled PNAs (OC-PNAs) with a high ratio of the radiative to intrinsic loss rates, which can be used for ultrasensitive spectroscopy at strong plasmonic-molecular detuning. In OC-PNAs, the ultrasensitive molecule signals are achieved within a wavelength detuning range of 248 cm-1 , which is 173 cm-1 wider than previous works. Meanwhile, the OC-PNAs are immune to the distortion of molecular signals and maintain a lineshape consistent with the molecular signature fingerprint. This strategy allows a single device to enhance and capture the full and complex fingerprint vibrations in the mid-infrared range. In the proof-of-concept demonstration, 13 kinds of molecules with some vibration fingerprints strongly detuning by the OC-PNAs are identified with 100% accuracy with the assistance of machine-learning algorithms. This work gains new insights into detuning-state nanophotonics for potential applications including spectroscopy and sensors.

2.
Shanghai Kou Qiang Yi Xue ; 30(4): 444-448, 2021 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34693443

RESUMO

PURPOSE: To investigate the clinical efficacy and safety of bipolar coagulation forceps combined with 1% lauromacrogol foam sclerotherapy in the treatment of microcystic lymphatic malformation of tongue. METHODS: The clinical data of 16 patients with microcystic lymphatic malformation of the tongue admitted to the Department of Stomatology of Foshan First People's Hospital from April 2017 to April 2020 were retrospectively analyzed, including 7 males and 9 females, aging from 15 months to 21 years. The average age of patients was 8.32±1.21 years. The efficacy and complications of the patients were evaluated. RESULTS: All 16 patients were followed up for 6 to 12 months. The clinical response was evaluated as eleven patients (68.75%) for grade Ⅳ, three (18.75%) for grade Ⅲ, two (12.5%) for grade Ⅱ, and the effective rate was 87.5%. Necrosis of tongue mucosa and muscle occurred in 1 patient. CONCLUSIONS: Bipolar coagulation forceps combined with 1% lauromacrogol foam sclerotherapy is a minimally invasive, safe and effective treatment for tongue microcystic lymphatic malformation.


Assuntos
Escleroterapia , Língua , Criança , Feminino , Humanos , Masculino , Polidocanol , Estudos Retrospectivos , Instrumentos Cirúrgicos
3.
Adv Sci (Weinh) ; 8(20): e2101879, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34423591

RESUMO

Multifunctional chemical sensing is highly desirable in industry, agriculture, and environmental sciences, but remains challenging due to the diversity of chemical substances and reactions. Surface-enhanced infrared absorption (SEIRA) spectroscopy can potentially address the above problems by ultra-sensitive detection of molecular fingerprint vibrations. Here, a multifunctional chemical sensing platform based on dual-resonant SEIRA device for sensitive and multifunctional on-chip detection of poly(ethyl cyanoacrylate) (PECA) is reported. It is experimentally demonstrated that the SEIRA sensing platform achieves multiple functions required by the PECA glue industry, including vibrational detection, thickness measurement, and in situ observation of polymerization and curing, which are usually realized by separately using a spectrometer, a viscometer, and an ellipsometer in the past. Specifically, the all-in-one sensor offers a dual-band fingerprint vibration identification, sub-nm level detection limit, and ultrahigh sensitivity of 0.76%/nm in thickness measurement, and second-level resolution in real-time observation of polymerization and curing. This work not only provides a valuable toolkit for ultra-sensitive and multifunctional on-chip detection of PECA, but also gives new insights into the SEIRA technology for multi-band, multi-functional, and on-chip chemical sensing.

4.
Micromachines (Basel) ; 12(7)2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34208991

RESUMO

The piezoelectric vibration energy harvester (PVEH) based on the variable cross-section cantilever beam (VCSCB) structure has the advantages of uniform axial strain distribution and high output power density, so it has become a research hotspot of the PVEH. However, its electromechanical model needs to be further studied. In this paper, the bidirectional coupled distributed parameter electromechanical model of the MEMS VCSCB based PVEH is constructed, analytically solved, and verified, which laid an important theoretical foundation for structural design and optimization, performance improvement, and output prediction of the PVEH. Based on the constructed model, the output performances of five kinds of VCSCB based PVEHs with different cross-sectional shapes were compared and analyzed. The results show that the PVEH with the concave quadratic beam shape has the best output due to the uniform surface stress distribution. Additionally, the influence of the main structural parameters of the MEMS trapezoidal cantilever beam (TCB) based PVEH on the output performance of the device is theoretically analyzed. Finally, a prototype of the Aluminum Nitride (AlN) TCB based PVEH is designed and developed. The peak open-circuit voltage and normalized power density of the device can reach 5.64 V and 742 µW/cm3/g2, which is in good agreement with the theoretical model value. The prototype has wide application prospects in the power supply of the wireless sensor network node such as the structural health monitoring system and the Internet of Things.

5.
Anal Chem ; 93(27): 9437-9444, 2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34170680

RESUMO

The novel coronavirus (COVID-19) is spreading globally due to its super contagiousness, and the pandemic caused by it has caused serious damage to the health and social economy of all countries in the world. However, conventional diagnostic methods are not conducive to large-scale screening and early identification of infected persons due to their long detection time. Therefore, there is an urgent need to develop a new COVID-19 test method that can deliver results in real time and on-site. In this work, we develop a fast, ultra-sensitive, and multi-functional plasmonic biosensor based on surface-enhanced infrared absorption for COVID-19 on-site diagnosis. The genetic algorithm intelligent program is utilized to automatically design and quickly optimize the sensing device to enhance the sensing performance. As a result, the quantitative detection of COVID-19 with an ultra-high sensitivity (1.66%/nm), a wide detection range, and a diverse measurement environment (gas/liquid) is achieved. In addition, the unique infrared fingerprint recognition characteristics of the sensor also make it an ideal choice for mutant virus screening. This work can not only provide a powerful diagnostic tool for the ultra-rapid, label-free, and multi-functional detection of COVID-19 but also help gain new insights into the field of label-free and ultrasensitive biosensing.


Assuntos
Técnicas Biossensoriais , COVID-19 , Algoritmos , Humanos , Pandemias , SARS-CoV-2
6.
Adv Sci (Weinh) ; 8(16): e2100583, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34155822

RESUMO

MicroRNAs play an important role in early development, cell proliferation, apoptosis, and cell death, and are aberrantly expressed in many types of cancers. To understand their function and diagnose cancer at an early stage, it is crucial to quantitatively detect microRNA without invasive labels. Here, a plasmonic biosensor based on surface-enhanced infrared absorption (SEIRA) for rapid, label-free, and ultrasensitive detection of miR-155 is reported. This technology leverages metamaterial perfect absorbers stimulating the SEIRA effect to provide up to 1000-fold near-field intensity enhancement over the microRNA fingerprint spectral bands. Additionally, it is discovered that the limit of detection (LOD) of the biosensor can be greatly improved by using tetrahedral DNA nanostructure (TDN) as carriers. By using near-field enhancement of SEIRA and specific binding of TDN, the biosensor achieves label-free detection of miR-155 with a high sensitivity of 1.162% pm-1 and an excellent LOD of 100 × 10-15 m. The LOD is about 5000 times lower than that using DNA single strand as probes and about 100 times lower than that of the fluorescence detection method. This work can not only provide a powerful diagnosis tool for the microRNAs detection but also gain new insights into the field of label-free and ultrasensitive SEIRA-based biosensing.


Assuntos
Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , DNA/química , MicroRNAs/análise , Nanoestruturas/química , Desenho de Equipamento , Humanos , Raios Infravermelhos , Limite de Detecção , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
7.
Shanghai Kou Qiang Yi Xue ; 30(2): 145-150, 2021 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-34109352

RESUMO

PURPOSE: To explore the DSA classification and treatment strategy of tongue venous malformation. METHODS: From February 2016 to February 2019, the DSA manifestations of 132 cases with venous malformations of the tongue were summarized. They were classified into 4 types according to imaging characteristics: typeⅠ(non-drainage type), typeⅡ(lower- drainage type), type Ⅲ (higher-drainage type), type Ⅳ(extensive type). Different therapeutic schemes were selected according to the types. The non- drainage type was treated with pingyangmycin alone, the lower-drainage type was treated with lauromacrogol foam alone, the higher- drainage type was treated with absolute alcohol combined with lauromacrogol foam, the extensive type was treated as higher-drainage type first and then combined with plastic resection. Among the cases, therapeutic effects and adverse reactions of each group were recorded and compared. RESULTS: One hundred and thirty-two cases in this study were followed up for 12 to 41 months with an average of 15.8 months. After sclerosing therapy, the venous malformations of the tongue of all patients significantly reduced or even disappeared. Type Ⅰincluded 8 cases with an efficiency of 100%, type Ⅱ included 17 cases with an efficiency of 100%, type Ⅲ included 98 cases with an efficiency of 90.8%, typeⅣincluded 9 cases, with an efficiency of 77.8%.The main adverse reactions were tissue necrosis: 0 in typeⅠ, 1(5.88%) in typeⅡ, 16(16.33%) in type Ⅲ, and 7(77.78%) in type Ⅳ. CONCLUSIONS: The classification of venous malformations of the tongue based on DSA is significant and valuable in guiding clinical treatment. The majority of tongue venous malformations are type Ⅲ, and the smallest propotion is type Ⅰ. Transmucosal sclerotherapy with absolute ethanol is of significance for the treatment of venous malformations of the tongue classified in type Ⅲ and type Ⅳ.


Assuntos
Soluções Esclerosantes , Malformações Vasculares , Humanos , Soluções Esclerosantes/uso terapêutico , Escleroterapia , Língua/diagnóstico por imagem , Resultado do Tratamento , Malformações Vasculares/tratamento farmacológico , Malformações Vasculares/terapia
8.
Adv Sci (Weinh) ; 8(15): e2101020, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34081406

RESUMO

The past few decades have witnessed the tremendous progress of human-machine interface (HMI) in communication, education, and manufacturing fields. However, due to signal acquisition devices' limitations, the research on HMI related to communication aid applications for the disabled is progressing slowly. Here, inspired by frogs' croaking behavior, a bionic triboelectric nanogenerator (TENG)-based ultra-sensitive self-powered electromechanical sensor for muscle-triggered communication HMI application is developed. The sensor possesses a high sensitivity (54.6 mV mm-1 ), a high-intensity signal (± 700 mV), and a wide sensing range (0-5 mm). The signal intensity is 206 times higher than that of traditional biopotential electromyography methods. By leveraging machine learning algorithms and Morse code, the safe, accurate (96.3%), and stable communication aid HMI applications are achieved. The authors' bionic TENG-based electromechanical sensor provides a valuable toolkit for HMI applications of the disabled, and it brings new insights into the interdisciplinary cross-integration between TENG technology and bionics.


Assuntos
Biônica/métodos , Técnicas Biossensoriais/métodos , Desenho de Equipamento/métodos , Músculos/fisiologia , Nanotecnologia/métodos , Dispositivos Eletrônicos Vestíveis , Fontes de Energia Elétrica
9.
Adv Sci (Weinh) ; 7(20): 2001173, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33101855

RESUMO

Simultaneous on-chip sensing of multiple greenhouse gases in a complex gas environment is highly desirable in industry, agriculture, and meteorology, but remains challenging due to their ultralow concentrations and mutual interference. Porous microstructure and extremely high surface areas in metal-organic frameworks (MOFs) provide both excellent adsorption selectivity and high gases affinity for multigas sensing. Herein, it is described that integrating MOFs into a multiresonant surface-enhanced infrared absorption (SEIRA) platform can overcome the shortcomings of poor selectivity in multigas sensing and enable simultaneous on-chip sensing of greenhouse gases with ultralow concentrations. The strategy leverages the near-field intensity enhancement (over 1500-fold) of multiresonant SEIRA technique and the outstanding gas selectivity and affinity of MOFs. It is experimentally demonstrated that the MOF-SEIRA platform achieves simultaneous on-chip sensing of CO2 and CH4 with fast response time (<60 s), high accuracy (CO2: 1.1%, CH4: 0.4%), small footprint (100 × 100 µm2), and excellent linearity in wide concentration range (0-2.5 × 104 ppm). Additionally, the excellent scalability to detect more gases is explored. This work opens up exciting possibilities for the implementation of all-in-one, real-time, and on-chip multigas detection as well as provides a valuable toolkit for greenhouse gas sensing applications.

10.
ACS Appl Mater Interfaces ; 8(1): 736-44, 2016 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-26654103

RESUMO

Understanding of the triboelectric charge accumulation from the view of materials plays a critical role in enhancing the output performance of triboelectric nanogenerator (TENG). In this paper, we have designed a feasible approach to modify the tribo-material of TENG by filling it with high permittivity nanoparticles and forming pores. The influence of dielectricity and porosity on the output performance is discussed experimentally and theoretically, which indicates that both the surface charge density and the charge transfer quantity have a close relationship with the relative permittivity and porosity of the tribo-material. A high output performance TENG based on a composite sponge PDMS film (CS-TENG) is fabricated by optimizing both the dielectric properties and the porosity of the tribo-material. With the combination of the enhancement of permittivity and production of pores in the PDMS film, the charge density of ∼19 nC cm(-2), open-circuit voltage of 338 V, and power density of 6.47 W m(-2) are obtained at working frequency of 2.5 Hz with the optimized film consisting of 10% SrTiO3 nanoparticles (∼100 nm in size) and 15% pores in volume, which gives over 5-fold power enhancement compared with the nanogenerator based on the pure PDMS film. This work gives a better understanding of the triboelectricity produced by the TENG from the view of materials and provides a new and effective way to enhance the performance of TENG from the material itself, not just its surface modification.

11.
J Mater Chem B ; 3(28): 5777-5785, 2015 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-32262574

RESUMO

A novel and exceptionally sensitive glucose biosensor based on nanorod-aggregated flower-like CuO grown on a carbon fiber fabric (CFF) is developed for glucose detection, which is prepared by a simple, fast and green hydrothermal method. The electron transfer resistance of the CuO/CFF electrode on the interface between the electrode and the electrolyte is as low as 12.79 Ω as evaluated by electrochemical impedance spectroscopy. A cyclic voltammetry study reveals that the CuO/CFF electrode displays an excellent electrocatalytic activity toward the direct oxidation of glucose. Besides, chronoamperometry demonstrates a high sensitivity of 6476.0 µA mM-1 cm-2 at an applied potential of 0.45 V (vs. Ag/AgCl), with a fast response time and a low detection limit of only 1.3 s and ∼0.27 µM, respectively. In addition, the glucose sensor has high reproducibility with a relative standard deviation (R.S.D.) of 1.53% over eight identically fabricated electrodes and long-term stability with a minimal sensitivity loss of ∼9.9% over a period of one month as well as excellent anti-interference ability. Importantly, the CuO-CFF composite has such good flexible characteristics and can be fabricated into flexible electrodes for application in various complicated circumstances. This work presents a new strategy to achieve highly sensitive glucose sensors with flexibility by growing glucose electroactive nanostructure materials directly on multichannels and highly conductive carbon fiber fabrics.

12.
Nanoscale ; 7(5): 1896-903, 2015 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-25526319

RESUMO

Nanogenerators with capacitor structures based on piezoelectricity, pyroelectricity, triboelectricity and electrostatic induction have been extensively investigated. Although the electron flow on electrodes is well understood, the maximum efficiency-dependent structure design is not clearly known. In this paper, a clear understanding of triboelectric generators with capacitor structures is presented by the investigation of polydimethylsiloxane-based composite film nanogenerators, indicating that the generator, in fact, acts as both an energy storage and output device. Maximum energy storage and output depend on the maximum charge density on the dielectric polymer surface, which is determined by the capacitance of the device. The effective thickness of polydimethylsiloxane can be greatly reduced by mixing a suitable amount of conductive nanoparticles into the polymer, through which the charge density on the polymer surface can be greatly increased. This finding can be applied to all the triboelectric nanogenerators with capacitor structures, and it provides an important guide to the structural design for nanogenerators. It is demonstrated that graphite particles with sizes of 20-40 nm and 3.0% mass mixed into the polydimethylsiloxane can reduce 34.68% of the effective thickness of the dielectric film and increase the surface charges by 111.27% on the dielectric film. The output power density of the triboelectric nanogenerator with the composite polydimethylsiloxane film is 3.7 W m(-2), which is 2.6 times as much as that of the pure polydimethylsiloxane film.

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