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1.
Opt Express ; 30(22): 40315-40327, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36298966

RESUMO

By precisely managing fiber-optic nonlinearity with anomalous dispersion, we have demonstrated the control of generating plural few-optical-cycle pulses based on a 24-MHz Chromium:forsterite laser, allowing multicolor two-photon tissue imaging by wavelength mixing. The formation of high-order soliton and its efficient coupling to dispersive wave generation leads to phase-matched spectral broadening, and we have obtained a broadband continuum ranging from 830 nm to 1200 nm, delivering 5-nJ pulses with a pulse width of 10.5 fs using a piece of large-mode-area fiber. We locate the spectral enhancement at around 920 nm for the two-photon excitation of green fluorophores, and we can easily compress the resulting pulse close to its limited duration without the need for active pulse shaping. To optimize the wavelength mixing for sum-frequency excitation, we have realized the management of the power ratio and group delay between the soliton and dispersive wave by varying the initial pulse energy without additional delay control. We have thus demonstrated simultaneous three-color two-photon tissue imaging with contrast management between different signals. Our source optimization leads to efficient two-photon excitation reaching a 500-µm imaging depth under a low 14-mW illumination power. We believe our source development leads to an efficient and compact approach for driving multicolor two-photon fluorescence microscopy and other ultrafast investigations, such as strong-field-driven applications.


Assuntos
Cromo , Fótons , Análise de Falha de Equipamento , Desenho de Equipamento , Microscopia de Fluorescência
2.
Sci Rep ; 12(1): 16140, 2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36167970

RESUMO

With the rise of environmental consciousness and the evolution of circular cities, the Internet of things (IoT) has been combined with the concept of circular economies to promote the effective control of renewable energy and resources. In this study, a comprehensive IoT system containing front-end device applications, network layer innovations, and cloud platform integrations was used in civil engineering applications. This IoT architecture is presented as a development basis for constructing modular automatic monitoring devices and integrating circular city concepts with the IoT. According to the concept of circular city, green circulation and energy use are systematically integrated and called "green energy". In addition, the green energy system can be divided into above-ground and underground. The above-ground part uses green roofs and solar panels for research and discussion. The composite solar green roofs of the two are called green roofs, and the comparison of their benefits is discussed on the spot. Narrowband IoT (NB-IoT) technologies were used in this study. The advantages of the developed system were analyzed using measured pH values, air temperatures, soil temperatures, and humidity. The results of this study indicate that constructing a green energy roof can decrease indoor temperatures by 1.5 °C and solar module temperatures by 1.6 °C while increasing power generation; thus, green energy roofs are suitable for tropical regions.

3.
Biomed Opt Express ; 12(5): 2888-2901, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34168906

RESUMO

We have demonstrated widely tunable Yb:fiber-based laser sources, aiming to replace Ti:sapphire lasers for the nJ-level ultrafast applications, especially for the uses of nonlinear light microscopy. We investigated the influence of different input parameters to obtain an expansive spectral broadening, enabled by self-phase modulation and further reshaped by self-steepening, in the normal dispersion regime before the fiber damage. We also discussed the compressibility and intensity fluctuations of the demonstrated pulses, to reach the transform-limited duration with a very low intensity noise. Most importantly, we have demonstrated clear two-photon fluorescence images from UV-absorbing fluorophores to deep red dye stains.

4.
J Endod ; 44(10): 1542-1548, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30170844

RESUMO

INTRODUCTION: In this study, we examined the effect of mineral trioxide aggregate (MTA) on macrophage polarization and the potential involvement of Axl/nuclear factor kappa B (NF-κB) signaling in mediating the effect of MTA. METHODS: The human monocyte cell line THP-1 was cultured with MTA solution for 1, 2, or 3 days, and the population change of M2 macrophages was analyzed by flow cytometry. Expression of M2 cytokines was examined by enzyme-linked immunosorbent assay. Phagocytosis and angiogenesis-induction ability were also assayed. The involvement of Axl/NF-κB signaling in MTA-treated cells was examined by analyzing phosphorylation status of Axl, Akt, IKKα/ß, and IκBα. Specific inhibitors for Axl/Akt/NF-κB signaling were added to MTA-treated THP-1 cells, and their cytokine expression change was examined. RESULTS: Flow cytometry analysis showed that MTA treatment increased CD206+ cells in a time-dependent way. After MTA treatment, the expression of M2-related cytokines was up-regulated. MTA also enhanced phagocytic ability and the ability of THP-1 cells to induce angiogenesis. Treatment of MTA led to activate Axl/Akt/NF-kB signal axis by phosphorylation of Axl, Akt, IKKα/ß, IκBα, and p65. In addition, MTA-induced interleukin 10, transforming growth factor beta, and vascular endothelial growth factor expression was suppressed as specific inhibitors were added. CONCLUSIONS: Our findings indicate that MTA is able to induce macrophage polarization toward the M2 phenotype, with up-regulation of interleukin 10, transforming growth factor beta, and vascular endothelial growth factor, and that Axl/Akt/NF-κB signaling participates in this process. These results provide the cellular and molecular basis of MTA's anti-inflammatory action in clinical applications.


Assuntos
Compostos de Alumínio/farmacologia , Anti-Inflamatórios , Compostos de Cálcio/farmacologia , Polaridade Celular/efeitos dos fármacos , Polaridade Celular/genética , Macrófagos/fisiologia , NF-kappa B/metabolismo , NF-kappa B/fisiologia , Óxidos/farmacologia , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas/fisiologia , Receptores Proteína Tirosina Quinases/metabolismo , Receptores Proteína Tirosina Quinases/fisiologia , Transdução de Sinais/fisiologia , Silicatos/farmacologia , Células Cultivadas , Citocinas/metabolismo , Combinação de Medicamentos , Humanos , Macrófagos/imunologia , Neovascularização Fisiológica/genética , Neovascularização Fisiológica/fisiologia , Fagocitose , Fosforilação/efeitos dos fármacos , Fosforilação/genética , Células THP-1 , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética , Receptor Tirosina Quinase Axl
5.
Plant Cell Physiol ; 44(8): 783-94, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12941870

RESUMO

An AP1/AGL9 group of MADS box gene, OMADS1, with extensive homology to the Arabidopsis AGAMOUS-like 6 gene (AGL6) was characterized from orchid (Oncidium Gower Ramsey). OMADS1 mRNA was detected in apical meristem and in the lip and carpel of flower. Yeast two-hybrid analysis indicated that OMADS1 is able to strongly interact with OMADS3, a TM6-like protein that was involved in flower formation and floral initiation in orchid. Transgenic Arabidopsis and tobacco ectopically expressed OMADS1 showed similar novel phenotypes by significantly reducing plant size, flowering extremely early, and losing inflorescence indeterminacy. In addition, homeotic conversion of sepals into carpel-like structures and petals into staminoid structures were also observed in flowers of 35S::OMADS1 Arabidopsis. This result indicated that OMADS1 was involved in floral formation and initiation in transgenic plants. Further analysis indicated that the expression of flowering time genes FT, SUPPRESSOR OF OVEREXPRESSION OF CO 1 (SOC1) and flower meristem identity genes LEAFY (LFY), APETALA1 (AP1) was significantly up-regulated in 35S::OMADS1 transgenic Arabidopsis plants. Furthermore, ectopic expression of OMADS1 rescued late-flowering phenotype in gi-1, co-3 but not for ft-1 and fwa-1 mutants. These results supported that ectopic expression of OMADS1 influenced flower transition and formation by acting as an activator for FT and SOC1 in Arabidopsis.


Assuntos
Arabidopsis/genética , Flores/genética , Orchidaceae/genética , Sequência de Aminoácidos , Arabidopsis/crescimento & desenvolvimento , Southern Blotting , Clonagem Molecular , DNA Complementar/isolamento & purificação , DNA de Plantas/isolamento & purificação , Dimerização , Flores/crescimento & desenvolvimento , Expressão Gênica , Genes Homeobox , Genes de Plantas , Dados de Sequência Molecular , Plantas Geneticamente Modificadas , Proteínas Recombinantes/genética , Nicotiana/genética
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