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1.
Appl Opt ; 61(27): 8115-8122, 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36255934

RESUMO

Plasmonic lasers, which use the strong confinement of surface plasmon polaritons, are key parts to realize ultracompact coherent light sources at deep subwavelength scales. We propose a plasmonic laser composed of a silicon substrate, ZnO nanowire, dielectric layer, metal layer, and electrode. In this structure, the superimposed coupling of the surface plasmon mode at the metal interface with the high refractive index gain nanowire mode makes the electric field in the spacer layer significantly enhanced. The ZnO nanowire is used as gain material to provide gain compensation. The optical and electrical properties are simulated with the geometric parameters and dielectric layer material. The results show that the structure has strong confinement of the optical field and can realize a deep subwavelength constraint at a lower threshold level. It provides theoretical support for realizing ultracompact coherent light sources.

2.
Nanotechnology ; 33(27)2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35299165

RESUMO

Nanoimprint technology has the advantages of low cost, high precision, high fidelity and high yield. The metal nanoparticle fluid is non-Newtonian fluid, which is used as the imprint transfer medium to realize high fidelity of pattern because of its shear thinning effect. In order to functionalize the metal nanoparticles microstructure, the subsequent sintering step is required to form a metal interconnect wire. Metal interconnect wire with fewer grain boundaries and fewer holes have excellent mechanical and electronic properties. In this paper, the pseudoplastic metal nanoparticle fluid was formed by Ag nanoparticle and precursor solution, and then the thermal diffusion process was completed by microwave sintering after interconnects were embossed. The influence of microwave and thermal atmosphere on the microstructure and performance of Ag Interconnect wires was analyzed and discussed, and the Ag Interconnect wires performance was determined under the influence of time and temperature parameters. In our experiments, the interconnects after microwave sintering can achieve 39% of the conductivity of bulk silver. The microwave sintering module might be integrated as the heat treatment module of the metal micro/nano pattern directly imprint lithography.

3.
IEEE Trans Med Robot Bionics ; 2(3): 437-446, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33763632

RESUMO

Femoroplasty is a proposed alternative therapeutic method for preventing osteoporotic hip fractures in the elderly. Previously developed navigation system for femoroplasty required the attachment of an external X-ray fiducial to the femur. We propose a fiducial-free 2D/3D registration pipeline using fluoroscopic images for robot-assisted femoroplasty. Intraoperative fluoroscopic images are taken from multiple views to perform registration of the femur and drilling/injection device. The proposed method was tested through comprehensive simulation and cadaveric studies. Performance was evaluated on the registration error of the femur and the drilling/injection device. In simulations, the proposed approach achieved a mean accuracy of 1.26±0.74 mm for the relative planned injection entry point; 0.63±0.21° and 0.17±0.19° for the femur injection path direction and device guide direction, respectively. In the cadaver studies, a mean error of 2.64 ± 1.10 mm was achieved between the planned entry point and the device guide tip. The biomechanical analysis showed that even with a 4 mm translational deviation from the optimal injection path, the yield load prior to fracture increased by 40.7%. This result suggests that the fiducial-less 2D/3D registration is sufficiently accurate to guide robot assisted femoroplasty.

4.
Nan Fang Yi Ke Da Xue Xue Bao ; 32(5): 606-9, 2012 May.
Artigo em Chinês | MEDLINE | ID: mdl-22588906

RESUMO

OBJECTIVE: To observe the effect of sodium valproate (VPA) on the proliferation and apoptosis of human lung carcinoma SPC-A1 cells and the underlying mechanism. METHODS: The effect of VPA on the proliferation of SPC-A1 cells was evaluated by MTT assay and clone formation assay. Flow cytometry was used to analyze the apoptosis of the cells exposed to VPA. The changes in the expressions of Bcl-xl, Bcl-2, Mcl-1, caspase-9, and caspase-3 in the exposed cells were detected by Western blotting. RESULTS: Incubation with VPA for 48 h resulted in a significant inhibition of SPC-A1 cell proliferation, with a IC(50) of 1.8 mmol/L. VPA treatment also inhibited cell colony formation and induced obvious cell apoptosis. Exposure to 8 mmol/L VPA for 48 h caused a percentage of early apoptotic cells of 60.44%. VPA treatment at different concentrations for 48 h obviously lowered the protein levels of Bcl-xl, Bcl-2, and Mcl-1 and induced caspase-9 and caspase-3 activation in SPC-A1 cells. CONCLUSION: VPA can inhibit the proliferation of SPC-A1 cells by triggering mitochondrion-dependent apoptosis.


Assuntos
Proliferação de Células/efeitos dos fármacos , Ácido Valproico/farmacologia , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Caspase 9/metabolismo , Linhagem Celular Tumoral , Humanos , Proteína de Sequência 1 de Leucemia de Células Mieloides , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína bcl-X/metabolismo
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