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1.
Nanomaterials (Basel) ; 14(8)2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38668146

RESUMEN

Dean flow and Dean instability play an important role in inertial microfluidics, with a wide application in mixing and sorting. However, most studies are limited to Dean flow in the microscale. This work first reports the application of Dean instability on organic nanoparticles synthesis at De up to 198. The channel geometry (the tortuous channel) is optimized by simulation, in which the mixing efficiency is considered. With the optimized design, prednisolone nanoparticles are synthesized, and the size of the most abundant prednisolone nanoparticles is down to 100 nm with an increase in the Re and De and smallest size down to 46 nm. This work serves as an ice-breaker to the real application of Dean instability by demonstrating its ability in mixing and nanomaterials like nanoparticle synthesis.

2.
Sensors (Basel) ; 24(8)2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38676200

RESUMEN

In diverse realms of research, such as holographic optical tweezer mechanical measurements, colloidal particle motion state examinations, cell tracking, and drug delivery, the localization and analysis of particle motion command paramount significance. Algorithms ranging from conventional numerical methods to advanced deep-learning networks mark substantial strides in the sphere of particle orientation analysis. However, the need for datasets has hindered the application of deep learning in particle tracking. In this work, we elucidated an efficacious methodology pivoted toward generating synthetic datasets conducive to this domain that resonates with robustness and precision when applied to real-world data of tracking 3D particles. We developed a 3D real-time particle positioning network based on the CenterNet network. After conducting experiments, our network has achieved a horizontal positioning error of 0.0478 µm and a z-axis positioning error of 0.1990 µm. It shows the capability to handle real-time tracking of particles, diverse in dimensions, near the focal plane with high precision. In addition, we have rendered all datasets cultivated during this investigation accessible.

3.
Soft Matter ; 20(16): 3436-3447, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38564251

RESUMEN

Flexible actuation materials play a crucial role in biomimetic robots. Seeking methods to enhance actuation and functionality is one of the directions in which actuators strive to meet the high-performance and diverse requirements of environmental conditions. Herein, by utilizing the method of adsorbing N-doped carbon dots (NCDs) onto SiO2 to form clusters of functional particles, a NCDs@SiO2/PDMS elastomer was prepared and its combined optical and electrical co-stimulation properties were effectively harnessed to develop a biomimetic crawling robot resembling Rhagophthalmus (firefly). The introduction of NCDs@SiO2 cluster particles not only effectively improves the mechanical and dielectric properties of the elastomer but also exhibits fluorescence response and actuation response under the co-stimulation of UV and electricity, respectively. Additionally, a hybrid dielectric elastomer actuator (DEA) with a transparent SWCNT mesh electrode exhibits two notable advancements: an 826% increase in out-of-plane displacement under low electric field stimulation compared to the pure matrix and the ability of NCDs to maintain a stable excited state within the polymer for an extended duration under UV-excitation. Simultaneously, the transparent biomimetic crawling robot can stealthily move in specific environments and fluoresce under UV light.

4.
Bioengineering (Basel) ; 11(4)2024 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-38671780

RESUMEN

In recent years, the proliferation of wearable healthcare devices has marked a revolutionary shift in the personal health monitoring and management paradigm. These devices, ranging from fitness trackers to advanced biosensors, have not only made healthcare more accessible, but have also transformed the way individuals engage with their health data. By continuously monitoring health signs, from physical-based to biochemical-based such as heart rate and blood glucose levels, wearable technology offers insights into human health, enabling a proactive rather than a reactive approach to healthcare. This shift towards personalized health monitoring empowers individuals with the knowledge and tools to make informed decisions about their lifestyle and medical care, potentially leading to the earlier detection of health issues and more tailored treatment plans. This review presents the fabrication methods of flexible wearable healthcare devices and their applications in medical care. The potential challenges and future prospectives are also discussed.

5.
Adv Sci (Weinh) ; : e2308422, 2024 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-38520724

RESUMEN

Accumulating evidence indicates that metabolic reprogramming of cancer cells supports the energy and metabolic demands during tumor metastasis. However, the metabolic alterations underlying lymph node metastasis (LNM) of cervical cancer (CCa) have not been well recognized. In the present study, it is found that lymphatic metastatic CCa cells have reduced dependency on glucose and glycolysis but increased fatty acid oxidation (FAO). Inhibition of carnitine palmitoyl transferase 1A (CPT1A) significantly compromises palmitate-induced cell stemness. Mechanistically, FAO-derived acetyl-CoA enhances H3K27 acetylation (H3K27Ac) modification level in the promoter of stemness genes, increasing stemness and nodal metastasis in the lipid-rich nodal environment. Genetic and pharmacological loss of CPT1A function markedly suppresses the metastatic colonization of CCa cells in tumor-draining lymph nodes. Together, these findings propose an effective method of cancer therapy by targeting FAO in patients with CCa and lymph node metastasis.

6.
Cell Mol Biol Lett ; 29(1): 25, 2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38331765

RESUMEN

BACKGROUND: Cervical cancer (CCa) is the fourth most common cancer among females, with high incidence and mortality rates. Circular RNAs (circRNAs) are key regulators of various biological processes in cancer. However, the biological role of circRNAs in cervical cancer (CCa) remains largely unknown. This study aimed to elucidate the role of circMAST1 in CCa. METHODS: CircRNAs related to CCa progression were identified via a circRNA microarray. The relationship between circMAST1 levels and clinicopathological features of CCa was evaluated using the clinical specimens and data of 131 patients with CCa. In vivo and in vitro experiments, including xenograft animal models, cell proliferation assay, transwell assay, RNA pull-down assay, whole-transcriptome sequencing, RIP assay, and RNA-FISH, were performed to investigate the effects of circMAST1 on the malignant behavior of CCa. RESULTS: CircMAST1 was significantly downregulated in CCa tissues, and low expression of CircMAST1 was correlated with a poor prognosis. Moreover, our results demonstrated that circMAST1 inhibited tumor growth and lymph node metastasis of CCa. Mechanistically, circMAST1 competitively sequestered N-acetyltransferase 10 (NAT10) and hindered Yes-associated protein (YAP) mRNA ac4C modification to promote its degradation and inhibit tumor progression in CCa. CONCLUSIONS: CircMAST1 plays a major suppressive role in the tumor growth and metastasis of CCa. In particular, circMAST1 can serve as a potential biomarker and novel target for CCa.


Asunto(s)
Citidina , ARN Circular , Neoplasias del Cuello Uterino , Animales , Femenino , Humanos , Línea Celular Tumoral , Citidina/análogos & derivados , ARN/genética , ARN Circular/genética , ARN Mensajero/metabolismo , Neoplasias del Cuello Uterino/genética
7.
Materials (Basel) ; 17(2)2024 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-38276450

RESUMEN

Low-temperature co-fired ceramic (LTCC) substrate materials are widely applied in electronic components due to their excellent microwave dielectric properties. However, the absence of LTCC materials with a lower dielectric constant and higher mechanical strength restricts the creation of integrated and minified electronic devices. In this work, sol-gel-derived CaO-B2O3-SiO2 (CBS) glass/Al2O3 composites with high flexural strength and low dielectric constant were successfully prepared using the LTCC technique. Among the composites sintered at different temperatures, the composites sintered at 870 °C for 2 hours possess a dielectric constant of 6.3 (10 GHz), a dielectric loss of 0.2%, a flexural strength of 245 MPa, and a CTE of 5.3 × 10-6 K-1, demonstrating its great potential for applications in the electronic package field. By analyzing the CBS glass' physical characteristics, it was found that the sol-gel-derived glass has an extremely low dielectric constant of 3.6 and does not crystallize or react with Al2O3 at the sintering temperature, which is conducive to improving the flexural strength and reducing the dielectric constant of CBS glass/Al2O3 composites.

8.
Sci Rep ; 13(1): 17896, 2023 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-37857780

RESUMEN

Dean's flow and Dean's instability have always been important concepts in the inertial microfluidics. Curved channels are widely used for applications like mixing and sorting but are limited to Dean's flow only. This work first reports the Dean's instability flow in high aspect ratio channels on the deka-microns level for [Formula: see text]. A new channel geometry (the tortuous channel), which creates a rolled-up velocity profile, is presented and studied experimentally and numerically along with other three typical channel geometries at Dean's flow condition and Dean's instability condition. The tortuous channel generates a higher De environment at the same Re compared to the other channels and allows easier Dean's instability creation. We further demonstrate the use of multiple vortexes for mixing. The mixing efficiency is considered among different channel patterns and the tortuous channel outperforms the others. This work offers more understanding of the creation of Dean's instability at high aspect ratio channels and the effect of channel geometry on it. Ultimately, it demonstrates the potential for applications like mixing and cell sorting.

9.
Artículo en Inglés | MEDLINE | ID: mdl-37883251

RESUMEN

With the help of neural network-based representation learning, significant progress has been recently made in data-driven online dynamic stability assessment (DSA) of complex electric power systems. However, without sufficient attention to diverse data loss conditions in practice, the existing data-driven DSA solutions' performance could be largely degraded due to practical defective input data. To address this problem, this work develops a robust representation learning approach to enhance DSA performance against multiple input data loss conditions in practice. Specifically, focusing on the short-term voltage stability (SVS) issue, an ensemble representation learning scheme (ERLS) is carefully designed to achieve data loss-tolerant online SVS assessment: 1) based on an efficient data masking technique, various missing data conditions are handled and augmented in a unified manner for lossy learning dataset preparation; 2) the emerging spatial-temporal graph convolutional network (STGCN) is leveraged to derive multiple diversified base learners with strong capability in SVS feature learning and representation; and 3) with massive SVS scenarios deeply grouped into a number of clusters, these STGCN-enabled base learners are distinctly assembled for each cluster via multilinear regression (MLR) to realize ensemble SVS assessment. Such a divide-and-conquer ensemble strategy results in highly robust SVS assessment performance when faced with various severe data loss conditions. Numerical tests on the benchmark Nordic test system illustrate the efficacy of the proposed approach.

10.
J Funct Biomater ; 14(4)2023 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-37103298

RESUMEN

Polydimethylsiloxane (PDMS) has been widely used to make lab-on-a-chip devices, such as reactors and sensors, for biological research. Real-time nucleic acid testing is one of the main applications of PDMS microfluidic chips due to their high biocompatibility and transparency. However, the inherent hydrophobicity and excessive gas permeability of PDMS hinder its applications in many fields. This study developed a silicon-based polydimethylsiloxane-polyethylene-glycol (PDMS-PEG) copolymer microfluidic chip, the PDMS-PEG copolymer silicon chip (PPc-Si chip), for biomolecular diagnosis. By adjusting the modifier formula for PDMS, the hydrophilic switch occurred within 15 s after contact with water, resulting in only a 0.8% reduction in transmittance after modification. In addition, we evaluated the transmittance at a wide range of wavelengths from 200 nm to 1000 nm to provide a reference for its optical property study and application in optical-related devices. The improved hydrophilicity was achieved by introducing a large number of hydroxyl groups, which also resulted in excellent bonding strength of PPc-Si chips. The bonding condition was easy to achieve and time-saving. Real-time PCR tests were successfully conducted with higher efficiency and lower non-specific absorption. This chip has a high potential for a wide range of applications in point-of-care tests (POCT) and rapid disease diagnosis.

11.
Molecules ; 28(3)2023 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-36770751

RESUMEN

Real-time polymerase chain reaction (real-time PCR) tests were successfully conducted in an aluminum-based microfluidic chip developed in this work. The reaction chamber was coated with silicone-modified epoxy resin to isolate the reaction system from metal surfaces, preventing the metal ions from interfering with the reaction process. The patterned aluminum substrate was bonded with a hydroxylated glass mask using silicone sealant at room temperature. The effect of thermal expansion was counteracted by the elasticity of cured silicone. With the heating process closely monitored, real-time PCR testing in reaction chambers proceeded smoothly, and the results show similar quantification cycle values to those of traditional test sets. Scanning electron microscope (SEM) and atomic force microscopy (AFM) images showed that the surface of the reaction chamber was smoothly coated, illustrating the promising coating and isolating properties. Energy-dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and inductively coupled plasma-optical emission spectrometer (ICP-OES) showed that no metal ions escaped from the metal to the chip surface. Fourier-transform infrared spectroscopy (FTIR) was used to check the surface chemical state before and after tests, and the unchanged infrared absorption peaks indicated the unreacted, antifouling surface. The limit of detection (LOD) of at least two copies can be obtained in this chip.

12.
Polymers (Basel) ; 16(1)2023 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-38201674

RESUMEN

Energy conservation in buildings is paramount, especially considering that glass accounts for 50% of energy consumption. The solar heat gain coefficient (SHGC) of glass is a critical energy-saving index for transparent structures. However, the fixed SHGC of ordinary glass makes it difficult to provide both summer shading and winter heating. In this study, we synthesized a hydrogel with a thermosensitive scattering (TS) property using triblock polyether and acrylamide. This hydrogel can realize the transition of clearness and atomization based on the temperature. When sealed within a glass cavity, it exhibits a high SHGC of 0.682 in its transparent state and a low SHGC of less than 0.31 when atomized. The lower critical solution temperature (LCST) of the TS glass can be adjusted from 0 to 70 °C to suit different regions. The photothermal properties of the material remained stable after 200 hot and cold cycles and 200 h of ultraviolet irradiation. This glass can prevent solar radiation from entering the room in summer, thereby reducing air conditioning usage and power consumption. In winter, it allows solar heat radiation to enter the room, minimizing the need for artificial heating. Its adaptable temperature design makes it an excellent solution for designers to create energy-efficient building exteriors.

13.
Nanomicro Lett ; 15(1): 3, 2022 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-36445558

RESUMEN

Photodetectors with long detection distances and fast response are important media in constructing a non-contact human-machine interface for the Masterly Internet of Things (MIT). All-inorganic perovskites have excellent optoelectronic performance with high moisture and oxygen resistance, making them one of the promising candidates for high-performance photodetectors, but a simple, low-cost and reliable fabrication technology is urgently needed. Here, a dual-function laser etching method is developed to complete both the lyophilic split-ring structure and electrode patterning. This novel split-ring structure can capture the perovskite precursor droplet efficiently and achieve the uniform and compact deposition of CsPbBr3 films. Furthermore, our devices based on laterally conducting split-ring structured photodetectors possess outstanding performance, including the maximum responsivity of 1.44 × 105 mA W-1, a response time of 150 µs in 1.5 kHz and one-unit area < 4 × 10-2 mm2. Based on these split-ring photodetector arrays, we realized three-dimensional gesture detection with up to 100 mm distance detection and up to 600 mm s-1 speed detection, for low-cost, integrative, and non-contact human-machine interfaces. Finally, we applied this MIT to wearable and flexible digital gesture recognition watch panel, safe and comfortable central controller integrated on the car screen, and remote control of the robot, demonstrating the broad potential applications.

14.
RSC Adv ; 12(49): 31959-31965, 2022 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-36380922

RESUMEN

Electrorheological (ER) fluid, containing polarized particles within an insulating liquid, represents a smart material, the mechanical properties of which can be altered mainly by an electric field. In this work, ER fluids based on cauliflower iron(ii) oxalate doped titanium particles show excellent rheological and wetting properties by the sample co-precipitation method. The morphology of the particles is observed by SEM and the molecular structure within the particles is obtained via XRD and FTIR. The distribution of elements within the particles is obtained by EDS. Owing to a lower current density than pure iron(ii) oxalate, the SEM and optical images show an obvious chain-like structure within the ER fluids with 2 wt% and 5 wt%, respectively, under 2 kV mm-1. Then, the rheological properties of these ER fluids are tested up to 3 kV mm-1 and the results show a gratifying property of resisting shear with different shear rates (0.1-100 s-1), which is attributed to the appearance of a stable chain-like structure. At the same time, the ER efficiency and the switching performance are obtained and the static yield stress fits the relevant electric field strength well. Ultimately, an excellent sedimentation ratio is obtained from 0 h to 600 h.

15.
Bioengineering (Basel) ; 9(10)2022 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-36290516

RESUMEN

With the evolution of the pandemic caused by the Coronavirus disease of 2019 (COVID-19), reverse transcriptase-polymerase chain reactions (RT-PCR) have invariably been a golden standard in clinical diagnosis. Nevertheless, the traditional polymerase chain reaction (PCR) is not feasible for field application due to its drawbacks, such as time-consuming and laboratory-based dependence. To overcome these challenges, a microchip-based ultrafast PCR system called SWM-02 was proposed to make PCR assay in a rapid, portable, and low-cost strategy. This novel platform can perform 6-sample detection per run using multiple fluorescent channels and complete an ultrafast COVID-19 RT-PCR test within 40 min. Here, we evaluated the performance of the microdevice using the gradient-diluted COVID-19 reference samples and commercial PCR kit and determined its limit-of-detection (LoD) as 500 copies/mL, whose variation coefficients for the nucleocapsid (N) gene and open reading frame 1 ab region (ORF1ab) gene are 1.427% and 0.7872%, respectively. The system also revealed an excellent linear correlation between cycle threshold (Ct) values and dilution factors (R2 > 0.99). Additionally, we successfully detected the target RNAs and internal gene in the clinical samples by fast PCR, which shows strong consistency with conventional PCR protocol. Hence, with compact dimension, user-friendly design, and fast processing time, SWM-02 has the capability of offering timely and sensitive on-site molecular diagnosis for prevention and control of pathogen transmission.

16.
Opt Lett ; 47(18): 4656-4659, 2022 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-36107056

RESUMEN

Optical microscopy has been widely used as a versatile tool in biological research. However, its penetration depth and spatial resolution are desperately limited by light scattering during deep propagation in turbid medium. Here, we implement near-infrared second window (1000-1700 nm) multifocal structured illumination microscopy (NIR-II MSIM) capable of deep penetration, high contrast, and enhanced spatial resolution. Raster-scanning multifocal illumination patterns ensure homogeneous illumination of the sample. By integrating NIR-II photoemission into multifocal photoexcitation, NIR-II MSIM affords deep imaging with improved lateral resolution (∼1.49 µm) at a depth of 2.5 mm in an Intralipid/agar phantom and outstanding contrast. Additionally, imaging at longer wavelength in the NIR-II region shows superior performance. This NIR-II MSIM system will afford a promising platform for studying physiological phenomena in turbid specimens in the future.


Asunto(s)
Iluminación , Microscopía , Agar , Iluminación/métodos , Microscopía/métodos , Fantasmas de Imagen
17.
Sci Rep ; 12(1): 8927, 2022 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-35624291

RESUMEN

The future satellite platform and 5G communication systems place high demands on antennas, in which the antenna should offer low-cost, lightweight, electronically steerable features. In this paper, the design of a digital slot antenna element based on substrate integrated waveguide (SIW) is proposed. SIW guides the microwave inside the substrate confined with planar metallic covers and through-hole synthetized side-walls in conventional applications, and can also radiate the microwave towards free space in antenna applications through opening slots in its metallic covers. The slot antenna element is realized by implementing PIN diodes across the gaps on both sides of the pad in the center of the slot antenna, to provide the switching freedom of the slot antenna element between radiating and non-radiating states. Besides, radial decoupling stubs are introduced into the bias line so as to reduce the leakage of the energy in the SIW structure. Applying a series of on/off states to the diodes produces various radiation patterns, thus wide range scanning is possible supposing that enough array elements are equipped. Finally, a digital SIW-slot array composed of 8 by 4 elements with tunable field programmable gate array circuits are fabricated and measured. The measured results validate the reconfigurable characteristics for the radiation pattern of the proposed digital SIW-slot antenna array without heavy engineering of phase shifter in conventional antenna arrays. The antenna is consisted by 4 by 8 elements and its dimension, simulated gain and radiation efficiency are 145 mm [Formula: see text] 127 mm [Formula: see text] 1.524 mm, 15 dBi and 53.5%, respectively. Our designed SIW antenna has the advantage of both size and weight. Furthermore, its digitalized control of beamforming allows a programming-friendly interface for smart antenna development.

18.
Soft Matter ; 18(20): 4031, 2022 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-35543092

RESUMEN

Correction for 'Efficient and stable electrorheological fluids based on chestnut-like cobalt hydroxide coupled with surface-functionalized carbon dots' by Yudai Liang et al., Soft Matter, 2022, DOI: 10.1039/D2SM00176D.

19.
Anal Bioanal Chem ; 414(11): 3349-3358, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35366071

RESUMEN

Point-of-care (POC) real-time polymerase chain reaction (PCR) has become one of the most important technologies for many fields such as pathogen detection and water-quality monitoring. POC real-time PCR usually adopts chips with small-volume chambers for portability, which is more likely to produce complex noise that seriously affects the accuracy. Such complex noises are difficult to be eliminated by the traditional fixed area algorithm that is most commonly used at present because they usually have random shape, location, and brightness. To address this problem, we proposed a novel image analysis method, Dynamic Deep Learning Noise Elimination Method (DIPLOID), in this paper. Our new method could recognize and output the mask of the interference by Mask R-CNN, and then subtract the interference and select the maximum valid contiguous area for brightness analysis by dynamic programming. Compared with the traditional method, DIPLOID increased the accuracy, sensitivity, and specificity from 57.9 to 94.6%, 49.1 to 93.9%, and 65.9 to 95.2%, respectively. DIPLOID has great anti-interference, robustness, and sensitivity, which can reduce the impact of complex noise as much as possible from the aspect of the algorithm. As shown in the experiments of this paper, our method significantly improved the accuracy to over 94% under the complex noise situation, which could make the POC real-time PCR have greater potential in the future.


Asunto(s)
Aprendizaje Profundo , Algoritmos , Procesamiento de Imagen Asistido por Computador , Reacción en Cadena en Tiempo Real de la Polimerasa
20.
Soft Matter ; 18(20): 3845-3855, 2022 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-35416233

RESUMEN

Intrinsically polarized electrorheological fluids (ERFs) have better thermal stability than ERFs with polar molecules, so they have a broader application prospect. However, the electrorheological efficiency of the common intrinsically polarized ERF is still lower than 1500, which is related to the poor wettability between polarized materials and the continuous phase. Carbon dots (CDs) exhibit good stability, semiconductor properties and low toxicity. We prepared biomimetic chestnut-like cobalt hydroxide coupled with surface-functionalized CD particles (Co(OH)2@CDs) by a simple hydrothermal method. Then we prepared an ERF by mixing Co(OH)2@CDs with silicone oil and studied the effect of CDs on its rheology and electrorheology properties. The synergistic effect of the lipophilic groups on the surface of CDs and the biomimetic chestnut-like structure makes Co(OH)2@CDs exhibit good wettability with silicone oil, and the optimal zero-field viscosity of Co(OH)2@CDs-ERF is only 0.46 Pa s (particle mass fraction of 40%). Exceptional electrorheological efficiency (about 10 000, shear rate 0.1 s-1, 5 kV mm-1) and dynamic shear stress stability of optimal Co(OH)2@CDs-ERF can be attributed to the dielectric enhancement of the biomimetic chestnut-like structure coupled with the semiconductor properties of CDs. In addition, Co(OH)2@CDs-ERF has excellent anti-settling performance, outstanding thermal stability and low current density.


Asunto(s)
Carbono , Aceites de Silicona , Carbono/química , Cobalto/química , Hidróxidos , Aceites de Silicona/química
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