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1.
Microsyst Nanoeng ; 10: 77, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38867942

RESUMO

With the modernization of traditional Chinese medicine (TCM), creating devices to digitalize aspects of pulse diagnosis has proved to be challenging. The currently available pulse detection devices usually rely on external pressure devices, which are either bulky or poorly integrated, hindering their practical application. In this work, we propose an innovative wearable active pressure three-channel pulse monitoring device based on TCM pulse diagnosis methods. It combines a flexible pressure sensor array, flexible airbag array, active pressure control unit, advanced machine learning approach, and a companion mobile application for human-computer interaction. Due to the high sensitivity (460.1 kPa-1), high linearity (R 2 > 0.999) and flexibility of the flexible pressure sensors, the device can accurately simulate finger pressure to collect pulse waves (Cun, Guan, and Chi) at different external pressures on the wrist. In addition, by measuring the change in pulse wave amplitude at different pressures, an individual's blood pressure status can be successfully predicted. This enables truly wearable, actively pressurized, continuous wireless dynamic monitoring of wrist pulse health. The innovative and integrated design of this pulse monitoring platform could provide a new paradigm for digitizing aspects of TCM and other smart healthcare systems.

2.
Nanoscale ; 16(15): 7427-7436, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38525943

RESUMO

Screen-printed interdigital electrode-based flexible pressure sensor arrays play a crucial role in human-computer interaction and health monitoring due to their simplicity of fabrication. However, the long-standing challenge of how to reduce the number of electrical output ports of interdigital electrodes to facilitate integration with back-end circuits is still commonly ignored. Here, we propose a screen-printing strategy to avoid wire cross-planes for rapid fabrication of flexible pressure sensor arrays. By innovatively introducing an insulating ink to realize electrical insulation and three-dimensional interconnection of wire crossings, the improved sensor array (4 × 4) successfully reduces the number of output ports from 17 to 8. In addition, we further constructed microstructures on the laser-etched electrode surfaces and the sensitive layer, which enabled the sensor to achieve a sensitivity as high as 17 567.5 kPa-1 in the range of 0-50 kPa. Moreover, we integrated the sensors with back-end circuits for the precise detection of tactile and physiological information. This provides a reliable method for preparing high-performance flexible sensor arrays and large-scale integration of microsensors.

3.
Micromachines (Basel) ; 15(2)2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38398909

RESUMO

The emerging field of flexible tactile sensing systems, equipped with multi-physical tactile sensing capabilities, holds vast potential across diverse domains such as medical monitoring, robotics, and human-computer interaction. In response to the prevailing challenges associated with the limited integration and sensitivity of flexible tactile sensors, this paper introduces a versatile tactile sensing system capable of concurrently monitoring temperature and pressure. The temperature sensor employs carbon nanotube/graphene conductive paste as its sensitive material, while the pressure sensor integrates an ionic gel containing boron nitride as its sensitive layer. Through the application of cost-effective screen printing technology, we have successfully manufactured a flexible dual-mode sensor with exceptional performance, featuring high sensitivity (804.27 kPa-1), a broad response range (50 kPa), rapid response time (17 ms), and relaxation time (34 ms), alongside exceptional durability over 5000 cycles. Furthermore, the resistance temperature coefficient of the sensor within the temperature range of 12.5 °C to 93.7 °C is -0.17% °C-1. The designed flexible dual-mode tactile sensing system enables the real-time detection of pressure and temperature information, presenting an innovative approach to electronic skin with multi-physical tactile sensing capabilities.

4.
Micromachines (Basel) ; 15(1)2024 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-38276858

RESUMO

Flexible conformal-enabled antennas have great potential for various developable surface-built unmanned aerial vehicles (UAVs) due to their superior mechanical compliance as well as maintaining excellent electromagnetic features. However, it remains a challenge that the antenna holds bending and thermal insensitivity to negligibly shift resonant frequency during conformal attachment and aerial flight, respectively. Here, we report a flexible symmetric-defection antenna (FSDA) with bending and thermal insensitivity. By engraving a symmetric defection on the reflective ground, the radiated unit attached to the soft polydimethylsiloxane (PDMS) makes the antenna resonate at the ISM microwave band (resonant frequency = 2.44 GHz) and conformal with a miniaturized UAV. The antenna is also insensitive to both the bending-conformal attachment (20 mm < r < 70 mm) and thermal radiation (20~100 °C) due to the symmetric peripheral-current field along the defection and the low-change thermal effect of the PDMS, respectively. Therefore, the antenna in a non-bending state almost keeps the same impedance matching and radiation when it is attached to a cylinder-back of a UAV. The flexible antenna with bending and thermal insensitivity will pave the way for more conformal or wrapping applications.

5.
Micromachines (Basel) ; 14(8)2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37630097

RESUMO

Dielectrophoresis technology is applied to microfluidic chips to achieve microscopic control of cells. Currently, microfluidic chips based on dielectrophoresis have certain limitations in terms of cell sorting species, in order to explore a microfluidic chip with excellent performance and high versatility. In this paper, we designed a microfluidic chip that can be used for continuous cell sorting, with the structural design of a curved channel and curved double side electrodes. CM factors were calculated for eight human healthy blood cells and cancerous cells using the software MyDEP, the simulation of various blood cells sorting and the simulation of the joule heat effect of the microfluidic chip were completed using the software COMSOL Multiphysics. The effect of voltage and inlet flow velocity on the simulation results was discussed using the control variables method. We found feasible parameters from simulation results under different voltages and inlet flow velocities, and the feasibility of the design was verified from multiple perspectives by measuring cell movement trajectories, cell recovery rate and separation purity. This paper provides a universal method for cell, particle and even protein sorting.

6.
Biosensors (Basel) ; 13(6)2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37367021

RESUMO

In recent years, flexible pressure sensing arrays applied in medical monitoring, human-machine interaction, and the Internet of Things have received a lot of attention for their excellent performance. Epidermal sensing arrays can enable the sensing of physiological information, pressure, and other information such as haptics, providing new avenues for the development of wearable devices. This paper reviews the recent research progress on epidermal flexible pressure sensing arrays. Firstly, the fantastic performance materials currently used to prepare flexible pressure sensing arrays are outlined in terms of substrate layer, electrode layer, and sensitive layer. In addition, the general fabrication processes of the materials are summarized, including three-dimensional (3D) printing, screen printing, and laser engraving. Subsequently, the electrode layer structures and sensitive layer microstructures used to further improve the performance design of sensing arrays are discussed based on the limitations of the materials. Furthermore, we present recent advances in the application of fantastic-performance epidermal flexible pressure sensing arrays and their integration with back-end circuits. Finally, the potential challenges and development prospects of flexible pressure sensing arrays are discussed in a comprehensive manner.


Assuntos
Epiderme , Dispositivos Eletrônicos Vestíveis , Humanos , Eletrodos , Impressão , Impressão Tridimensional
7.
Microsyst Nanoeng ; 9: 68, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37251710

RESUMO

Recently, flexible iontronic pressure sensors (FIPSs) with higher sensitivities and wider sensing ranges than conventional capacitive sensors have been widely investigated. Due to the difficulty of fabricating the nanostructures that are commonly used on electrodes and ionic layers by screen printing techniques, strategies for fabricating such devices using these techniques to drive their mass production have rarely been reported. Herein, for the first time, we employed a 2-dimensional (2D) hexagonal boron nitride (h-BN) as both an additive and an ionic liquid reservoir in an ionic film, making the sensor printable and significantly improving its sensitivity and sensing range through screen printing. The engineered sensor exhibited high sensitivity (Smin> 261.4 kPa-1) and a broad sensing range (0.05-450 kPa), and it was capable of stable operation at a high pressure (400 kPa) for more than 5000 cycles. In addition, the integrated sensor array system allowed accurate monitoring of wrist pressure and showed great potential for health care systems. We believe that using h-BN as an additive in an ionic material for screen-printed FIPS could greatly inspire research on 2D materials for similar systems and other types of sensors. Hexagonal boron nitride (h-BN) was employed for the first time to make iontronic pressure sensor arrays with high sensitivity and a broad sensing range by screen printing.

8.
Rev Sci Instrum ; 94(5)2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37212645

RESUMO

Periodically tunable nano-gratings have an irreplaceable role in spectral scanning and optical communication, but the performance of gratings manufactured from different materials varies considerably, and the development of superior materials has energized the preparation of high-precision devices. This paper presents a nanoscale preparation process based on Norland Optical Adhesive 73 (NOA73), which enables the rapid preparation of periodically tunable nano-gratings with up to 100% light transmission. The powerful fluidity and shear rate of NOA73 make it uniquely suited to the preparation of precision devices, allowing the production of up to dense grating structures and offering the possibility of making nanoscale gratings. This paper uses multi-angle hierarchical lithography, die stretching, and replication to achieve further improvements in accuracy and successfully prepare gratings with a period of 500 nm. The successful preparation of NOA73 nano-gratings demonstrates the practicality of NOA73 as a material for precision device fabrication.

9.
Micromachines (Basel) ; 13(9)2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-36144018

RESUMO

With the development of cross-fertilisation in various disciplines, flexible wearable sensing technologies have emerged, bringing together many disciplines, such as biomedicine, materials science, control science, and communication technology. Over the past few years, the development of multiple types of flexible wearable devices that are widely used for the detection of human physiological signals has proven that flexible wearable devices have strong biocompatibility and a great potential for further development. These include electronic skin patches, soft robots, bio-batteries, and personalised medical devices. In this review, we present an updated overview of emerging flexible wearable sensor devices for biomedical applications and a comprehensive summary of the research progress and potential of flexible sensors. First, we describe the selection and fabrication of flexible materials and their excellent electrochemical properties. We evaluate the mechanisms by which these sensor devices work, and then we categorise and compare the unique advantages of a variety of sensor devices from the perspective of in vitro and in vivo sensing, as well as some exciting applications in the human body. Finally, we summarise the opportunities and challenges in the field of flexible wearable devices.

10.
Polymers (Basel) ; 13(20)2021 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-34685224

RESUMO

Researchers are showing an increasing interest in high-performance flexible pressure sensors owing to their potential uses in wearable electronics, bionic skin, and human-machine interactions, etc. However, the vast majority of these flexible pressure sensors require extensive nano-architectural design, which both complicates their manufacturing and is time-consuming. Thus, a low-cost technology which can be applied on a large scale is highly desirable for the manufacture of flexible pressure-sensitive materials that have a high sensitivity over a wide range of pressures. This work is based on the use of a three-dimensional elastic porous carbon nanotubes (CNTs) sponge as the conductive layer to fabricate a novel flexible piezoresistive sensor. The synthesis of a CNTs sponge was achieved by chemical vapor deposition, the basic underlying principle governing the sensing behavior of the CNTs sponge-based pressure sensor and was illustrated by employing in situ scanning electron microscopy. The CNTs sponge-based sensor has a quick response time of ~105 ms, a high sensitivity extending across a broad pressure range (less than 10 kPa for 809 kPa-1) and possesses an outstanding permanence over 4000 cycles. Furthermore, a 16-pixel wireless sensor system was designed and a series of applications have been demonstrated. Its potential applications in the visualizing pressure distribution and an example of human-machine communication were also demonstrated.

11.
Int J Clin Oncol ; 25(8): 1492-1498, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32447474

RESUMO

BACKGROUND: The ALTER 0303 study showed that anlotinib can significantly improve overall survival (OS) compared with the placebo in advanced non-small-cell lung cancer (NSCLC). Hand-foot syndrome (HFS) is a common anlotinib-related adverse event. The aim of this study was to assess the association of HFS with clinical benefit. METHODS: A subgroup analysis of patients treated with anlotinib from the ALTER 0303 study was performed. Our analysis assessed if the appearance of anlotinib-related HFS in the first 42 days (second-cycle HFS) and at any time could produce better clinical benefits. RESULTS: In this study, 294 patients were treated with anlotinib. Of which, 129 patients had HFS at any time, and 76 patients developed HFS in the first 2 cycles. Patients who received anlotinib and developed HFS had significantly prolonged OS, progression-free survival (PFS) compared to those who did not develop HFS in the first 2 cycles (13.5 vs 8.7 months, p = 0.001; adjusted hazard ratio (HR) 0.63 (95% confidence interval [CI] 0.44-0.89), p = 0.009; 5.8 vs 4.5 months, p = 0.001; adjusted HR, 0.59 [0.43-0.81], p = 0.001). The significant OS and PFS benefits for patients with HFS versus without were seen at any time (14.5 vs 7.3 months, p = 0.000; adjusted HR, 0.50 [0.36-0.67], p = 0.000; 5.8 vs 4.2 months, p = 0.000; adjusted HR, 0.49 [0.37-0.65], p = 0.000). In addition, the grade of severity of HFS was strongly correlated with OS (p = 0.000). CONCLUSION: Presence of HFS may be a potential clinical marker for the treatment of NSCLC with anlotinib.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Síndrome Mão-Pé/etiologia , Indóis/efeitos adversos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/mortalidade , Quinolinas/efeitos adversos , Adulto , Idoso , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/patologia , Feminino , Humanos , Indóis/uso terapêutico , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Intervalo Livre de Progressão , Modelos de Riscos Proporcionais , Quinolinas/uso terapêutico , Resultado do Tratamento
12.
J Cell Physiol ; 235(2): 1296-1308, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31273792

RESUMO

With the participation of the existing treatment methods, the prognosis of advanced clear-cell renal cell carcinoma (ccRCC) is poor. More evidence indicates the presence of methylation in ccRCC cancer cells, but there is a lack of studies on methylation-driven genes in ccRCC. We analyzed the open data of ccRCC in The Cancer Genome Atlas database to obtain ccRCC-related methylation-driven genes, and then carried out pathway enrichment, survival, and joint survival analyses. More important, we deeply explored the correlation between differential methylation sites and the expression of these driving genes. Finally, we screened 29 methylation-driven genes via MethylMix, of which six were significantly associated with the survival of ccRCC patients. This study demonstrated that the effect of hypermethylation or hypomethylation on prognosis is different, and the level of methylation of key methylation sites is associated with gene expression. We identified methylation-driven genes independently predicting prognosis in ccRCC, which offers theoretical support in bioinformatics for the study of methylation in ccRCC and a new perspective for the epigenetic study of ccRCC.


Assuntos
Carcinoma de Células Renais/genética , Regulação Neoplásica da Expressão Gênica/genética , Neoplasias Renais/genética , Regiões Promotoras Genéticas/genética , Biomarcadores Tumorais/genética , Carcinoma de Células Renais/patologia , Biologia Computacional/métodos , Metilação de DNA/fisiologia , Epigenômica , Humanos , Neoplasias Renais/patologia , Prognóstico
13.
Oncotarget ; 8(43): 75712-75726, 2017 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-29088904

RESUMO

After the discovery of activating mutations in EGFR, EGFR tyrosine kinase inhibitors (TKIs) have been introduced into the first-line treatment of non-small-cell lung cancer (NSCLC). A series of studies have shown that EGFR TKI monotherapy as first-line treatment can benefit NSCLC patients harbouring EGFR mutations. Besides, combination strategies based on EGFR TKIs in the first line treatment have also been proved to delay the occurrence of resistance. In this review, we summarize the scientific literature and evidence of EGFR TKIs as first-line therapy from the first-generation EGFR TKIs to conceptually proposed fourth-generation EGFR TKI, and also recommend the application of monotherapy and combination therapies of the EGFR-based targeted therapy with other agents such as chemotherapy, anti-angiogenic drugs and immunecheckpoint inhibitors.

14.
Phys Chem Chem Phys ; 16(35): 18858-65, 2014 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-25081032

RESUMO

Molecular dynamics simulations were performed to clarify the nanomechanical responses of ß-Si3N4 nano-thin layers in the basal plane for indenters of various radii, different indentation velocities and at different temperatures. It was found that the maximum loading stress and indenter displacement both increase with increasing radius of the indenter. A large number of N(6h)-Si bond-breaking defects and one N(2c)-Si bond-breaking defects are responsible for the initiation of fracturing. With increasing loading velocity, the maximum loading stresses show almost no change; however, a high loading velocity can shorten the displacement of the indenter and contributes to the formation of new N(2c)-Si bond-breaking defects. Thermal fluctuations can decrease the mechanical properties of the thin layer. The maximum loading stresses and indenter displacements are sensitive to both the radius of the indenter and the loading temperature.

15.
J Phys Chem Lett ; 4(11): 1878-81, 2013 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-26283124

RESUMO

We report molecular dynamics simulations of the nanomechanical properties and fracture mechanisms of ß-Si3N4 thin layers in a prismatic plane under uniaxial tension. It is found that the thin layers in the y loading direction display a linear stress-strain relationship at ε < 0.021, and afterward, the stress increases nonlinearly with the strain until fracture occurs. However, for the z direction, the linear response is located at ε < 0.051. The calculated fracture stresses and strains of the thin layers increase with strain rates both in both directions. The thin layers exhibit the higher Young's modulus of 0.345 TPa in the z direction, higher than that in the y direction. The origins of crack derive from N(2c-1)-Si and N(6h-1)-Si bonds for the y and z loading directions, respectively.

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