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1.
Small ; 20(3): e2300733, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37452437

RESUMO

Relapse and unresectability have become the main obstacle for further improving hepatocellular carcinoma (HCC) treatment effect. Currently, single therapy for HCC in clinical practice is limited by postoperative recurrence, intraoperative blood loss and poor patient outcomes. Multidisciplinary therapy has been recognized as the key to improving the long-term survival rate for HCC. However, the clinical application of HCC synthetic therapy is restricted by single functional biomaterials. In this study, a magnetic nanocomposite hydrogel (CG-IM) with iron oxide nanoparticle-loaded mica nanosheets (Iron oxide nanoparticles@Mica, IM) is reported. This biocompatible magnetic hydrogel integrated high injectability, magnetocaloric property, mechanical robustness, wet adhesion, and hemostasis, leading to efficient HCC multidisciplinary therapies including postoperative tumor margin treatment and percutaneous locoregional ablation. After minimally invasive hepatectomy of HCC, the CG-IM hydrogel can facilely seal the bleeding hepatic margin, followed by magnetic hyperthermia ablation to effectively prevent recurrence. In addition, CG-IM hydrogel can inhibit unresectable HCC by magnetic hyperthermia through the percutaneous intervention under ultrasound guidance.


Assuntos
Silicatos de Alumínio , Carcinoma Hepatocelular , Hipertermia Induzida , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/patologia , Hidrogéis/farmacologia , Fenômenos Magnéticos
2.
Mol Cell Biochem ; 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38472681

RESUMO

Triple-negative breast cancer (TNBC) is the most lethal subtype of BC, with unfavorable treatment outcomes. Evidence suggests the engagement of lncRNA MCM3AP-AS1 in BC development. This study investigated the action of MCM3AP-AS1 in chemoresistance of TNBC cells. Drug-resistant TNBC cell lines SUM159PTR and MDA-MB-231R were constructed by exposure to increasing concentrations of doxorubicin/docetaxel (DOX/DXL). MCM3AP-AS1 and miR-524-5p expression levels were determined by RT-qPCR. RNA binding motif 39 (RBM39) level was measured using Western blot. Cell viability and apoptosis were assessed by CCK-8 assay and flow cytometry. The targeted binding of miR-524-5p with MCM3AP-AS1 or RBM39 was predicted by ECORI database and validated by dual-luciferase assays. The gain-and-loss of function assays were conducted in cells to investigate the interactions among MCM3AP-AS1, miR-524-5p, and RBM39. TNBC xenograft mouse models were established through subcutaneous injection of MCM3AP-AS1-silencing MDA-MB-231R cells and intraperitoneally administrated with DOX/DXL to verify the role of MCM3AP-AS1 in vivo. MCM3AP-AS1 was upregulated in drug-resistant TNBC cells, and MCM3AP-AS1 silencing could sensitize drug-resistant TNBC cells to chemotherapeutic drugs by promoting apoptosis. MCM3AP-AS1 targeted miR-524-5p. After DOX/DXL treatment, miR-524-5p inhibition partially reversed the effect of MCM3AP-AS1 silencing on inhibiting chemoresistance and promoting apoptosis of drug-resistant TNBC cells. miR-524-5p targeted RBM39. Silencing MCM3AP-AS1 promoted apoptosis via the miR-524-5p/RBM39 axis, thereby enhancing chemosensitivity of drug-resistant TNBC cells. MCM3AP-AS1 knockdown upregulated miR-524-5p, downregulated RBM39, and restrained tumor development in vivo. MCM3AP-AS1 silencing potentiates apoptosis of drug-resistant TNBC cells by upregulating miR-524-5p and downregulating RBM39, thereby suppressing chemoresistance in TNBC.

3.
Langmuir ; 37(50): 14744-14752, 2021 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-34813700

RESUMO

Flow condensation in nanochannels is a high-efficiency method to deal with increasingly higher heat flux from micro/nanoelectronic devices. Here, we study the flow condensation heat transfer characteristics of nanochannels with different nanopillar cross-sectional areas and heights using molecular dynamics simulation. Results show that two phases containing vapor in the middle of the channel and liquid near walls can be distinguished by obvious interfaces when the fluid is at a stable state. The condensation performance can be promoted by adding nanopillars. With the increase in nanopillar cross-sectional areas or heights, the time that the fluid spends to reach stability will be put off, while the condensation performance enhances. Different from the small enhancement of nanopillar cross-sectional areas, the condensation heat transfer performance improves significantly at a higher nanopillar height, which increases the heat transfer rates by 11.6 and 35.8% when heights are 6a and 8a, respectively. The preeminent condensation heat transfer performance is ascribed to the fact that nanopillars with a higher height disturb the vapor-liquid interface and vapor region, which not only allows vapor atoms with strong Brownian motion to collide with nanopillar atoms directly but also increases deviations of vapor-liquid potential energy to facilitate condensation heat transfer in nanochannels.


Assuntos
Temperatura Alta , Simulação de Dinâmica Molecular , Gases , Movimento (Física)
4.
Opt Express ; 28(10): 15529-15541, 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32403579

RESUMO

Modulation and direct measurement of the radial fluence distribution inside a single filament core (especially less than 100 µm in diameter) is crucial to filament-based applications. We report direct measurements of the radial fluence distribution inside a femtosecond laser filament core and its evolution via the filament-induced ablation method. The radial fluence distributions were modulated by manipulating the input pulse diffraction through an iris. Compared with using a traditionally circular iris, a stellate iris substantially suppressed the diffraction effect, and laser fluence, intensity and plasma density inside the filament core were considerably increased. The radial fluence inside filament cores was also quantitatively measured via the filament drilling diaphragms approach. Furthermore, numerical simulations were performed to support the experimental results by solving nonlinear Schrödinger equations. The effects of the tooth size of the stellate iris were numerically investigated, which indicated that bigger tooth favors higher fluence and longer filament. In addition to being beneficial in understanding the filamentation process and its control, the results of this study can also be valuable for filament-based applications.

5.
Opt Lett ; 45(16): 4444-4447, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32796979

RESUMO

We experimentally investigate the laser polarization effect on the supercontinuum (SC) generation through femtosecond laser filamentation in air. By tuning filamenting laser ellipticity from linear polarization to circular polarization, the spectral intensity of the SC after filamentation gradually increases, while the spectral bandwidth of the SC continuously decreases. The laser ellipticity-dependent spectral intensity modulation of the SC is stronger at higher filamenting pulse energy. Laser energy deposits more in linearly polarized laser filaments than in circularly polarized laser filaments. The experimental results are supported by numerical simulations. A physical picture based on the laser ellipticity-dependent clamped intensity inside the filament, together with the Kerr nonlinearity and plasma related self-phase modulations, is proposed to explain the observation.

6.
Opt Express ; 26(23): 29687-29699, 2018 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-30469930

RESUMO

AgI-type pyrotechnics are widely used in the field of weather modification, as a kind of artificial ice nuclei. However, their precipitation yield remains an intensively studied area. In this paper, we present a study of AgI-type pyrotechnic nucleant-induced water condensation promoted by femtosecond laser filaments in a cloud chamber. It is found that when 50-ml sample was irradiated by the laser filaments, the particles condensed on the glass slide are more soluble and slightly larger (5-15 µm). The irradiation of the laser filament on the nucleant rarely induces the generation of particles of sizes larger than 1 µm; however, it increases the decay time of particles from 13 to 18 min by the creation of numerous small particles. The amount of snow on the cold bottom plate increases by 4.2-13.1% in 2 h, compared to that without the irradiation of the laser filament. These results are associated with the production of high-concentration HNO3 by the laser filament. The concentration of HNO3 in the melt water increases by more than ten times when the sample was irradiated by the laser filaments.

7.
Opt Express ; 26(3): 2785-2793, 2018 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-29401814

RESUMO

Water condensation and precipitation induced by 22-TW 800-nm laser pulses at 1 Hz in an open cloud chamber were investigated in a time-resolved manner. Two parts of precipitation in two independent periods of time were observed directly following each laser shot. One part started around the filament zone at t < 500 µs and ended at t ≅ 1.5 ms after the arrival of the femtosecond laser pulse. The other following the laser-induced energetic air motion (turbulence), started at t ≅ 20 ms and ended at t ≅ 120 ms. Meanwhile, the phase transitions of large-size condensation droplets with diameters of 400-500 µm from liquid to solid (ice) in a cold area (T < -30 °C) were captured at t ≅ 20 ms.

8.
Phys Rev Lett ; 121(25): 255002, 2018 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-30608806

RESUMO

By using a millijoule kHz femtosecond laser pulse to irradiate a preformed expanding spherical plasma, which is driven by a prepulse with intensity of 1×10^{14} W/cm^{2}, we observe fast-electron-mediated filamentary structures and an accompanying self-organized magnetic-tube array with 2000 T via time-resolved magneto-optical polarization rotation measurements. We reveal that these periodical filamentary structures predominantly originate from ejected energetic electron flows from the inner denser region of the spherical plasma, which will induce the electron Weibel instability and magnetic field organization and amplification in the expanding plasma in 2 ps. These results open new paths to investigate amplification of intense magnetic fields and the radiation signature from gamma-ray bursts just by means of a much smaller and robust experimental platform.

9.
Opt Express ; 25(10): 11078-11087, 2017 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-28788791

RESUMO

We present a novel method based on plasma-guided corona discharges to probe the plasma density longitudinal distribution, which is particularly good for the weakly ionized plasmas (~1014 cm-3). With this method, plasma density longitudinal distribution inside both a weakly ionized plasma and a filament were characterized. When a high voltage electric field was applied onto a plasma channel, the original ionization created by a laser pulse would be enhanced and streamer coronas formed along the channel. By measuring the fluorescence of enhanced ionization, in particular, on both ends of a filament, the weak otherwise invisible plasma regions created by the laser pulse were identified. The observed plasma guided coronas were qualitatively understood by solving a 3D Maxwell equation through finite element analysis. The technique paves a new way to probe low density plasma and to precisely measure the effective length of plasma inside a filament.

10.
Opt Express ; 24(7): 7364-73, 2016 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-27137026

RESUMO

We investigated femtosecond laser-filamentation-induced airflow, water condensation and snow formation in a cloud chamber filled respectively with air, argon and helium. The mass of snow induced by laser filaments was found being the maximum when the chamber was filled with argon, followed by air and being the minimum with helium. We also discussed the mechanisms of water condensation in different gases. The results show that filaments with higher laser absorption efficiency, which result in higher plasma density, are beneficial for triggering intense airflow and thus more water condensation and precipitation.

11.
Opt Express ; 24(18): 20494-506, 2016 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-27607654

RESUMO

We investigated water condensation in a laboratory cloud chamber induced by picosecond (ps) laser pulses at ~350 ps (800 nm/1-1000 Hz) with a maximum peak power of ~25 MW. The peak power was much lower than the critical power for self-focusing in air (~3-10 GW depending on the pulse duration). Sparks, airflow and snow formation were observed under different laser energies or repetition rates. It was found that weaker ps laser pulses can also induce water condensation by exploding and breaking down ice crystals and/or water droplets into tiny particles although there was no formation of laser filament. These tiny particles would grow until precipitation in a super-saturation zone due to laser-induced airflow in a cold region with a large temperature gradient.

12.
J Colloid Interface Sci ; 664: 704-715, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38492371

RESUMO

The rational design and optimization of heterogeneous interface for low loading noble metal HER eletrocatalysts to facilitate the upscaling of alkaline water/seawater electrolysis is highly challenging. Herein, we present a facile deep corrosion strategy induced by NaBH4 to precisely construct an ultrasmall Ru nanoparticle-decorated Ni/NiO hybrid (r-Ru-Ni/NiO) with highly dispersed triple-phase heterostructures. Remarkably, it exhibits superior activity with only 53 mV and 70 mV at 100 mA cm-2 for hydrogen evolution reaction (HER) in alkaline water and seawater, respectively, surpassing the performance of Pt/C (109.7 mV, 100 mA cm-2, 1 M KOH). It is attributed to collaborative optimization of electroactive interfaces between well-distributed ultrasmall Ru nanoparticles and Ni/NiO hybrid. Moreover, the assembled r-Ru-Ni/NiO system just require 2.03 V at 1000 mA cm-2 in anion exchange membrane (AEM) electrolyzer, outperforming a RuO2/NF || Pt/C system, while exhibiting outstanding stability at high current densities. This study offers a logical design for accurate construction of interfacial engineering, showing promise for large-scale hydrogen production via electrochemical water splitting.

13.
Gene ; 909: 148257, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38367851

RESUMO

BACKGROUND: Inflammatory Bowel Disease (IBD) is a chronic inflammatory disorder of the gastrointestinal tract with an unknown etiology. Although dysbiosis is implicated in its pathogenesis, deep sequencing and oral microbiota study in Chinese IBD patients is absent. AIM: To explore the role of oral / intestinal microbiota in patients with IBD and the potential associations therein. METHODS: Clinical data, fecal and saliva samples were harvested from 80 patients with IBD (Crohn's disease, CD, n = 69; Ulcerative colitis, UC, n = 11) and 24 normal controls. Microbiomics (16S rRNA sequencing and 16S rRNA full-length sequencing) were used to detect and analyze the difference between IBD patients and normal control. RESULTS: Compared with normal controls, a higher abundance of the intestinal Shigella spp. (Shigella flexneri and Shigella sonnei, which were positively relate to the severity of IBD), lower abundance of intestinal probiotics (Prevotella, Faecalibacterium and Roseburia), and higher abundance of oral Neisseria were present in IBD patients with microbiome. The higher inflammation-related markers, impaired hepatic and renal function, and dyslipidaemia were present in patients with IBD. A higher intake of red meat and increased abundance of Clostridium in the gut were found in CD patients, while the elevated abundance of Ruminococcus in the gut was showed in UC ones. The bacterial composition of saliva and fecal samples was completely different, yet there was some correlation in the distribution of dominant probiotics. CONCLUSION: Enteric dysbacteriosis and the infections of pathogenic bacteria (Shigella) may associate with the occurrence or development of IBD.


Assuntos
Colite Ulcerativa , Doença de Crohn , Doenças Inflamatórias Intestinais , Microbiota , Humanos , RNA Ribossômico 16S/genética , Fezes/microbiologia , Disbiose/microbiologia
14.
Opt Express ; 21(8): 9255-66, 2013 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-23609636

RESUMO

We numerically simulated the air-flow motion in a diffusion cloud chamber induced by femtosecond laser filaments for different chopping rates. A two dimensional model was employed, where the laser filaments were treated as a heat flux source. The simulated patterns of flow fields and maximum velocity of updraft compare well with the experimental results for the chopping rates of 1, 5, 15 and 150 Hz. A quantitative inconsistency appears between simulated and experimental maximum velocity of updraft for 1 kHz repetition rate although a similar pattern of flow field is obtained, and the possible reasons were analyzed. Based on the present simulated results, the experimental observation of more water condensation/snow at higher chopping rate can be explained. These results indicate that the specific way of laser filament heating plays a significant role in the laser-induced motion of air flow, and at the same time, our previous conclusion of air flow having an important effect on water condensation/snow is confirmed.


Assuntos
Gases/química , Gases/efeitos da radiação , Lasers , Modelos Químicos , Reologia/métodos , Simulação por Computador , Calefação/métodos , Espalhamento de Radiação
15.
Stud Health Technol Inform ; 308: 733-742, 2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-38007805

RESUMO

This article introduces the modeling idea of complex neural networks based on the analysis of Parkinson's disease(PD) seizures. According to the Hodgkin-Huxley model of neurons and the synaptic connection theory between neurons, a theoretical model of the basal ganglia circuit was established. To reveal the working mechanism of the brain during the attack of nervous system disease. On this basis, the neural system model is combined with the control theory. Finally, an intermittent adaptive feedback controller is proposed to effectively suppress the onset of Parkinson's disease by stimulating the neuronal system accordingly.


Assuntos
Estimulação Encefálica Profunda , Doença de Parkinson , Humanos , Doença de Parkinson/terapia , Encéfalo , Redes Neurais de Computação , Estimulação Elétrica , Modelos Teóricos
16.
Nanoscale ; 15(30): 12737-12747, 2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37477114

RESUMO

Understanding the water flow behavior on an anisotropic wetting surface is of practical significance in nanofluidic devices for their performance improvement. However, current methods of experiments and simulations face challenges in measuring water transportation in real time and visually displaying it. Here, molecular dynamics simulation was integrated with our developed multi-attribute point cloud dataset and a customized network of deep learning to achieve mapping from an anisotropic wetting surface to the static and dynamic behaviors of water molecules and realize the high-performance prediction of water transport behavior. More importantly, for the chaotic phenomenon of water molecule flow caused by thermal fluctuation and limited sampling, we proposed a nanoparticle tracking optimization strategy to improve the prediction performance of the velocity field. The prediction results proved that the deep learning framework proposed in this work had superior performance in terms of accuracy, computational cost and visualization, and had the potential for generality to model the transport behavior of different molecules. Our framework can be expected to motivate the development of real-time water flow prediction at an interface and contribute to the optimization and design of surface structures in nanofluidic devices.

17.
ACS Appl Mater Interfaces ; 15(4): 5099-5108, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36652634

RESUMO

Water management in the catalyst layers (CLs) of proton-exchange membrane fuel cells is crucial for its commercialization and popularization. However, the high experimental or computational cost in obtaining water distribution and diffusion remains a bottleneck in the existing experimental methods and simulation algorithms, and further mechanistic exploration at the nanoscale is necessary. Herein, we integrate, for the first time, molecular dynamics simulation with our customized analysis framework based on a multiattribute point cloud dataset and an advanced deep learning network. This was achieved through our workflow that generates simulated transport data of water molecules in the CLs as the training and test dataset. Deep learning framework models the multibody solid-liquid system of CLs on a molecular scale and completes the mapping from the Pt/C substrate structure and Nafion aggregates to the density distribution and diffusion coefficient of water molecules. The prediction results are comprehensively analyzed and error evaluated, which reveals the highly anisotropic interaction landscape between 50,000 pairs of interacting nanoparticles and explains the structure and water transport property relationship in the hydrated Nafion film on the molecular scale. Compared to the conventional methods, the proposed deep learning framework shows computational cost efficiency, accuracy, and good visual display. Further, it has a generality potential to model macro- and microscopic mass transport in different components of fuel cells. Our framework is expected to make real-time predictions of the distribution and diffusion of water molecules in CLs as well as establish statistical significance in the structural optimization and design of CLs and other components of fuel cells.

18.
Opt Lett ; 37(7): 1214-6, 2012 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-22466199

RESUMO

Using 1 kHz, 9 mJ femtosecond laser pulses, we demonstrate laser-filamentation-induced spectacular snow formation in a cloud chamber. An intense updraft of warm moist air is generated owing to the continuous heating by the high-repetition filamentation. As it encounters the cold air above, water condensation and large-sized particles spread unevenly across the whole cloud chamber via convection and cyclone like action on a macroscopic scale. This indicates that high-repetition filamentation plays a significant role in macroscopic laser-induced water condensation and snow formation.

19.
Opt Lett ; 36(11): 2125-7, 2011 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-21633470

RESUMO

We report the formation of inverted microstructures inside glasses after femtosecond laser irradiation by tuning the refractive index contrast between the immersion liquid and the glass sample. By using water as well as 1-bromonaphthalene as immersion liquids, microstructures with similar shape but opposite directions are induced after femtosecond laser irradiation. Interestingly, the elemental distribution in the induced structures is also inverted. The simulation of laser intensity distribution along the laser propagation direction indicates that the interfacial spherical aberration effect is responsible for the inversion of microstructures and elemental distribution.

20.
Opt Express ; 18(6): 6262-9, 2010 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-20389649

RESUMO

The redistribution of elements in a multicomponent oxyfluoride glass is induced by a 250 kHz femtosecond laser. Elemental distribution in the cross section of the modified region along the laser propagation axis is analyzed by an electron microprobe analyzer. The results indicate that the relative concentrations of network formers of the glass are higher in the central area of the modified region and lower in the periphery of the modified region compared with the unirradiated areas. However, the relative concentrations of network modifiers are as opposed to that of network formers. Fluorescence spectra confirm that the distribution of fluorescence intensity of Yb(3+) in the modified region is consistent with that of its concentration. The effects of spherical aberration of the incident beam on the elemental redistribution are also discussed.


Assuntos
Vidro/química , Vidro/efeitos da radiação , Lasers , Teste de Materiais
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