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1.
Materials (Basel) ; 17(8)2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38673205

RESUMO

The exceptional corrosion resistance and combined physical and chemical self-cleaning capabilities of superhydrophobic photocatalytic coatings have sparked significant interest among researchers. In this paper, we propose an economical and eco-friendly superhydrophobic epoxy resin coating that incorporates SiO2@CuO/HDTMS nanoparticles modified with Hexadecyltrimethoxysilane (HDTMS). The application of superhydrophobic coatings effectively reduces the contact area between the metal surface and corrosive media, leading to a decreased corrosion rate. Additionally, the incorporation of nanomaterials, exemplified by SiO2@CuO core-shell nanoparticles, improves the adhesion and durability of the coatings on aluminum alloy substrates. Experimental data from Tafel curve analysis and electrochemical impedance spectroscopy (EIS) confirm the superior corrosion resistance of the superhydrophobic modified aluminum alloy surface compared to untreated surfaces. Estimations indicate a significant reduction in corrosion rate after superhydrophobic treatment. Furthermore, an optical absorption spectra analysis of the core-shell nanoparticles demonstrates their suitability for photocatalytic applications, showcasing their potential contribution to enhancing the overall performance of the coated surfaces. This research underscores the promising approach of combining superhydrophobic properties with photocatalytic capabilities to develop advanced surface modification techniques for enhanced corrosion resistance and functional properties in diverse industrial settings.

2.
Fish Shellfish Immunol ; 124: 421-429, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35429624

RESUMO

Numerous studies have proved that endoplasmic reticulum (ER)-stress is an important cause of aquatic animal diseases. Therefore, for effectively preventing and controlling aquatic animal diseases, a systematic and in-depth understanding of the environmental stress response in aquatic animals is necessary. In present study, the influence of ER-stress in Litopenaeus vannamei was investigated using Illumina HiSeq based RNA-Seq. Comparing to the cDNA library of hemocytes treated with DMSO in L. vannamei, 286 unigenes were significantly upregulated and 473 unigenes were significantly down-regulated in the Thapsigargin treated group. KEGG analysis indicated that the differentially expressed genes (DEGs) are mainly related to ER-stress, immune as well as metabolism. Besides the classical ER-stress response pathways, the regulation of cell cycle and DNA replication are also important measures of ER-stress response. It has been suggested that the influence of ER-stress on immune genes might be an important factor in environmental stress inducing shrimp disease. Our investigation exhibited that immune-related DEG Prophenoloxidase activating enzyme 2 (LvPPAE2) roled in anti-pathogen immunity of shrimp. This study provides a solid foundation for uncovering the environmental adaptation response and especially its relationship with L. vannamei immune system.


Assuntos
Doenças dos Animais , Penaeidae , Doenças dos Animais/metabolismo , Animais , Retículo Endoplasmático , Perfilação da Expressão Gênica/veterinária , Hemócitos , Transcriptoma
3.
Int J Mol Sci ; 23(1)2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-35008992

RESUMO

In shrimp, several glutathione peroxidase (GPX) genes have been cloned and functionally studied. Increasing evidence suggests the genes' involvement in white spot syndrome virus (WSSV)- or Vibrio alginolyticus-infection resistance. In the present study, a novel GXP gene (LvGPX3) was cloned in Litopenaeus vannamei. Promoter of LvGPX3 was activated by NF-E2-related factor 2. Further study showed that LvGPX3 expression was evidently accelerated by oxidative stress or WSSV or V. alginolyticus infection. Consistently, downregulated expression of LvGPX3 increased the cumulative mortality of WSSV- or V. alginolyticus-infected shrimp. Similar results occurred in shrimp suffering from oxidative stress. Moreover, LvGPX3 was important for enhancing Antimicrobial peptide (AMP) gene expression in S2 cells with lipopolysaccharide treatment. Further, knockdown of LvGPX3 expression significantly suppressed expression of AMPs, such as Penaeidins 2a, Penaeidins 3a and anti-lipopolysaccharide factor 1 in shrimp. AMPs have been proven to be engaged in shrimp WSSV- or V. alginolyticus-infection resistance; it was inferred that LvGPX3 might enhance shrimp immune response under immune challenges, such as increasing expression of AMPs. The regulation mechanism remains to be further studied.


Assuntos
Resistência à Doença/genética , Glutationa Peroxidase/genética , Estresse Oxidativo/genética , Penaeidae/genética , Penaeidae/metabolismo , Animais , Peptídeos Antimicrobianos/genética , Clonagem Molecular , Expressão Gênica , Técnicas de Silenciamento de Genes , Predisposição Genética para Doença , Penaeidae/microbiologia , Penaeidae/virologia , Filogenia , Análise de Sequência
4.
Fish Shellfish Immunol ; 120: 180-189, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34838985

RESUMO

The interplay between virus and host has been one of the hot spot in virology, and it is also the important aspect of revealing the mechanism of virus infection. Increasing studies revealed that several key molecules took part in the process of virus-host interaction. White spot syndrome virus (WSSV) has been proved to affect several physiological processes of the host cells, especially apoptosis. While the relationship between them still remains unclear. In this study, a IFI27 gene (LvIFI27) of Litopenaeus vannamei was cloned. It is indicated that LvIFI27 was induced upon endoplasmic reticulum (ER)-stress and unfolded protein response activator Thapsigargin. Unlike human IFI27 locating to mitochondria, LvIFI27 lied to ER, and was involved in cell apoptosis process. Moreover, results of cumulative mortality analysis showed that LvIFI27 might contributed to WSSV proliferation by promoting apoptosis during the process of viral infection. Findings in this study enriched our understanding of the relationship between WSSV infection and ER-stress mediated apoptosis.


Assuntos
Proteínas de Artrópodes , Infecções por Vírus de DNA/veterinária , Estresse do Retículo Endoplasmático , Proteínas de Membrana/genética , Penaeidae , Animais , Apoptose , Proteínas de Artrópodes/genética , Penaeidae/genética , Penaeidae/virologia , Resposta a Proteínas não Dobradas , Vírus da Síndrome da Mancha Branca 1
5.
Fish Shellfish Immunol ; 119: 339-346, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34653667

RESUMO

Seeking out fish meal (FM) alternatives is an important requirement for aquaculture all over the world. And most practitioners believe that the plant protein is most potential for FM surrenal. While high plant protein feed caused some common problems in aquatic livestock: the absorption rate and growth rate are decreased, and even caused digestive tract inflammation. In present study, the inflence of high plant protien feed in Trachinotus ovatus was investigated using illumina HiSeqTM2000 based RNA-Seq. By comparing the two groups of cDNA libraries developed from high plant protien based diet or FM based diet fed T. ovatus livers, 836 unigenes were significantly upregulated, and 345 were significantly down regulated. KEGG analysis indicated that the differentially expressed genes (DEGs) are mainly metabolic-related genes. It was found that more than 28 DGEs beloned to the protein metabolism and absorption, lipid biosynthesis or other metabolic pathways. It indicated that high plant protein based diet had broad effects on metabolism on T. ovatus. There were also more DEGs belong to immune-related signaling pathways, include genes were involved in pathpathogen resistance and genes related to immunity system. These DEGs provided useful clues to explore the mechanisms that high plant protein based diet caused side effects on T. ovatus. These results improved our current understanding of the response of high plant protein based diet in T. ovatus, and outstanding the reasons of the side effect caused by high protein based diet.


Assuntos
Ração Animal , Proteínas de Plantas , Ração Animal/análise , Animais , Dieta/veterinária , Peixes/genética , Perfilação da Expressão Gênica/veterinária , Fígado , Proteínas de Plantas/genética , Transcriptoma
6.
Fish Shellfish Immunol ; 117: 104-112, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34333126

RESUMO

Cell survival is based on the stability of intracellular state. It was well known that biochemical reactions in cells require specific intracellular environments, such as pH and calcium concentration. While the mechanism of stabilizing the intracellular environment is complex and far from clear. In this study, a Sma and Mad related protein 5 gene (LvSmad5) of Litopenaeus vannamei was cloned. LvSmad5 was located to both cytoplasm and nucleus. And subcellular localization of LvSmad5 was responsed to the changing of cells internal and external environment. Besides, it was found that subcellular localization of LvSmad5 was also regulated by unfolded protein response. Moreover, it was proved that nucleic localization of LvSmad5 could significantly increase the white spot syndrome virus (WSSV) infection in shrimp, and knockdown expression of LvSmad5 decreased the cumulative mortality of WSSV infection shrimp. Further investigation revealed that cytoplasm LvSmad5 could interplay with shrimp hexokinase 1, and contribute to glycolysis. These results indicated that LvSmad5 played a role in L. vannamei environmental stress response, and was used by WSSV for its replication.


Assuntos
Infecções por Vírus de DNA/genética , Doenças dos Peixes/genética , Proteínas de Peixes/genética , Penaeidae/genética , Proteína Smad5/genética , Estresse Fisiológico/genética , Vírus da Síndrome da Mancha Branca 1/fisiologia , Sequência de Aminoácidos , Animais , Núcleo Celular , Clonagem Molecular , Citoplasma , Infecções por Vírus de DNA/mortalidade , Infecções por Vírus de DNA/veterinária , Infecções por Vírus de DNA/virologia , Doenças dos Peixes/mortalidade , Doenças dos Peixes/virologia , Penaeidae/virologia , Resposta a Proteínas não Dobradas/genética , Replicação Viral
7.
Fish Shellfish Immunol Rep ; 2: 100033, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36420483

RESUMO

RNA interference (RNAi) is a conservative and important functional pathway in eukaryocyte. It regulates the expression of genes that are engaged in a variety of cellular physiological functions. Among the functions of RNAi, its antiviral function have attracted many attentions.The RNAi pathway molecules are able to recognize virus-related dsRNA and degrade it, therefore killing the virus. More importantly, RNAi could mediate systemic antiviral responses, transmit from cell to cell, and systemic RNA interference defective 1 (SID1) was thought to play an important role in this process. In the present study, a SID1 gene (LvSID1) of Litopenaeus vannamei was cloned. LvSID1 could locate to both plasma membrane and endoplasmic reticulum. Result of real-time RT-PCR assay showed that it was highly expressed in shrimp gills. Besides, it was shown that over-expressed LvSID1 in Sf9 cells could significant enchane RNAi efficiency. It was found that the expression of LvSID1was regulated by white spot syndrome virus (WSSV), and knockdown expression of LvSID1 increased the cumulative mortality of WSSV infection shrimp. These results suggested that LvSID1 likely to played a role in L. vannamei systemic RNAi, and was involved in WSSV resistence.

8.
IEEE Trans Vis Comput Graph ; 27(2): 475-484, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33048720

RESUMO

We present an integrated approach for creating and assigning color palettes to different visualizations such as multi-class scatterplots, line, and bar charts. While other methods separate the creation of colors from their assignment, our approach takes data characteristics into account to produce color palettes, which are then assigned in a way that fosters better visual discrimination of classes. To do so, we use a customized optimization based on simulated annealing to maximize the combination of three carefully designed color scoring functions: point distinctness, name difference, and color discrimination. We compare our approach to state-of-the-art palettes with a controlled user study for scatterplots and line charts, furthermore we performed a case study. Our results show that Palettailor, as a fully-automated approach, generates color palettes with a higher discrimination quality than existing approaches. The efficiency of our optimization allows us also to incorporate user modifications into the color selection process.

9.
Fish Shellfish Immunol ; 107(Pt B): 547-555, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33161091

RESUMO

Tripartite motif (TRIM) family proteins are named by the presence of tripartite motifs in their amino terminal domains. Apart from the amino terminal, their carboxyl terminal contain variable domains which mediate diverse functions of the TRIM proteins. It had been found that TRIM proteins played important roles in distinct biological processes, such as innate immunity, anti-tumor immunity, cell cycle regulation and so on. In the present study, we cloned a TRIM32 (LvTRIM32) gene from Litopenaeus vannamei. LvTRIM32 was highly expressed in hemocytes, gills and epidermis, and subcellular localization analysis indicated that it was widely distributed in S2 cells. In vitro ubiquitination assays indicated that LvTRIM32 had E3 ubiquitin ligase activity. Results of real-time RT-PCR assay showed that LvTRIM32 was induced in shrimp hemocytes upon oxidative stress. It was also proved that the promoter activity of LvTRIM32 was enhanced by NF-E2-related factor, and knocked-down expression of LvTRIM32 depressed the expression of malic enzyme and epoxide hydrolase. Downregulated LvTRIM32 suppressed the cumulative mortality of shrimp under oxidative stress. Moreover, it was found that LvTRIM32 could be induced in shrimp hemocytes upon immunostimulation, and downregulated LvTRIM32 increased the cumulative mortality of shrimp infected with white spot syndrome virus (WSSV) or Vibrio alginolyticus. Collecting results suggested that LvTRIM32 was a member of shrimp antioxidant stress system, and it was also involved in WSSV- or V. alginolyticus-infection resistance.


Assuntos
Proteínas de Artrópodes/genética , Imunidade Inata/genética , Estresse Oxidativo/genética , Penaeidae/genética , Penaeidae/imunologia , Proteínas com Motivo Tripartido/genética , Vírus da Síndrome da Mancha Branca 1/fisiologia , Animais , Proteínas de Artrópodes/imunologia , Proteínas de Artrópodes/metabolismo , Perfilação da Expressão Gênica , Hemócitos/imunologia , Proteínas com Motivo Tripartido/imunologia , Proteínas com Motivo Tripartido/metabolismo
10.
Fish Shellfish Immunol ; 93: 977-985, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31449979

RESUMO

C-type lectins (CTLs), which bind carbohydrates in a Ca2+-dependent manner, are involved in many cellular activities, especially immunity. CTLs play important roles in both the antibacterial and the antiviral immune response and are also associated with autoimmunity. Several CTLs have been investigated in crustaceans, primarily with respect to their function in the immune response. In this study, we cloned a novel CTL gene (LvCTLU) from Litopenaeus vannamei. LvCTLU is involved in microbe agglutination and phagocytosis. Downregulating LvCTLU increased the cumulative mortality of L. vannamei after Vibrio parahemolyticus infection. Similar to other reported CTLs, LvCTLU also had antiviral properties. Downregulation of LvCTLU also increased the cumulative mortality of L. vannamei after infection with white spot syndrome virus. More importantly, LvCTLU expression was induced by the unfolded protein response (UPR), which is the key pathway in the endoplasmic reticulum (ER)-stress response of eukaryotic organism. Our results suggested that this protein might be involved in the shrimp ER-stress response. Reporter gene assay indicated that LvCTLU was regulated by X-box-binding protein 1, which is the key transcription factor in the UPR. Our study thus revealed that LvCTLU plays vital roles in both the anti-pathogen immune response and the ER-stress response.


Assuntos
Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Lectinas Tipo C/genética , Lectinas Tipo C/imunologia , Penaeidae/genética , Penaeidae/imunologia , Proteína 1 de Ligação a X-Box/genética , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/química , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/imunologia , Sequência de Bases , Perfilação da Expressão Gênica , Lectinas Tipo C/química , Filogenia , Alinhamento de Sequência , Vírus da Síndrome da Mancha Branca 1/fisiologia , Proteína 1 de Ligação a X-Box/metabolismo
11.
J Mol Neurosci ; 65(2): 222-233, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29845511

RESUMO

Mesenchymal stem cell (MSC) therapy is a promising prospect for the treatment of Alzheimer's disease (AD); however, the underlying mechanisms by which MSCs mediate positive effects are still unclear. We speculated that MSCs mediate microglial autophagy and enhance the clearance of Aß. To test this hypothesis, we cultured BV2 microglial cells with umbilical cord mesenchymal stem cells conditioned medium (ucMSCs-CM) in the presence or absence of Aß25-35 oligomers. We investigated BV2 cell proliferation, cell death, and Aß25-35 phagocytosis as well as protein expression levels of LC3, Beclin-1, p62, insulin-degrading enzyme (IDE), and neprilysin (Nep) with western blotting. The results showed that ucMSCs-CM inhibited the proliferation and decreased cell death of BV2 cells induced by Aß25-35. ucMSCs-CM also promoted the phagocytosis of Aß25-35 by BV2 cells and changed the expression of autophagy-related proteins LC3, Beclin-1, and p62. Treatment also upregulated the expression of Aß-degrading enzymes IDE and Nep. Furthermore, the culture medium in BV2 cells with Aß25-35 and ucMSCs-CM prevented neuronal cell SH-SY5Y from cell death compared to control medium without ucMSCs-CM. Altogether, these data suggested that ucMSCs-CM protect microglial and neuronal cells from Aß25-35-induced cell death and promote Aß phagocytosis by modulating autophagy and enhancing the expression of Aß-degrading enzymes in microglia.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Autofagia , Células-Tronco Mesenquimais/metabolismo , Microglia/metabolismo , Fragmentos de Peptídeos/metabolismo , Fagocitose , Proteólise , Animais , Proteína Beclina-1/genética , Proteína Beclina-1/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Células Cultivadas , Meios de Cultivo Condicionados/farmacologia , Humanos , Insulisina/genética , Insulisina/metabolismo , Camundongos , Microglia/efeitos dos fármacos , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Neprilisina/genética , Neprilisina/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Cordão Umbilical/citologia
12.
IEEE Trans Vis Comput Graph ; 24(1): 489-499, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28866589

RESUMO

We present an improved stress majorization method that incorporates various constraints, including directional constraints without the necessity of solving a constraint optimization problem. This is achieved by reformulating the stress function to impose constraints on both the edge vectors and lengths instead of just on the edge lengths (node distances). This is a unified framework for both constrained and unconstrained graph visualizations, where we can model most existing layout constraints, as well as develop new ones such as the star shapes and cluster separation constraints within stress majorization. This improvement also allows us to parallelize computation with an efficient GPU conjugant gradient solver, which yields fast and stable solutions, even for large graphs. As a result, we allow the constraint-based exploration of large graphs with 10K nodes - an approach which previous methods cannot support.

13.
J Biophotonics ; 3(1-2): 108-16, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19768706

RESUMO

The morphological alterations of human cutaneous normal scar were quantitatively analyzed using multiphoton microscopy (MPM) based on two-photon excited fluorescence and second harmonic generation. High-contrast, high-resolution images of normal scar and uninjured skin were obtained for comparison. In addition, some quantitative parameters have been extracted to quantitatively discriminate between normal scar and uninjured skin. The MPM combined with quantitative method enable a better understanding of microstructual alterations of the epidermis, elastic fiber, and collagen in normal scar. It may lead the way to making know the mechanism of normal scar formation and identifying feasible therapeutic options.


Assuntos
Cicatriz/patologia , Microscopia de Fluorescência por Excitação Multifotônica/métodos , Pele/patologia , Adulto , Cicatriz/metabolismo , Colágeno/metabolismo , Derme/anatomia & histologia , Derme/metabolismo , Derme/patologia , Tecido Elástico/anatomia & histologia , Tecido Elástico/metabolismo , Tecido Elástico/patologia , Epiderme/anatomia & histologia , Epiderme/metabolismo , Epiderme/patologia , Feminino , Humanos , Imageamento Tridimensional/métodos , Pessoa de Meia-Idade , Tamanho do Órgão , Pele/anatomia & histologia , Pele/metabolismo
14.
Skin Res Technol ; 15(4): 489-95, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19832963

RESUMO

BACKGROUND/PURPOSE: A real-time, non-invasive method will confer a benefit for the diagnosis and treatment of localized scleroderma (LS) in the clinic. The aim of this work was to demonstrate the potential of multiphoton laser scanning microscopy (MPLSM) for diagnosing LS and monitoring the treatment response in vivo. METHODS: Three sclerodermatous skin specimens and two normal skin specimens were investigated using MPLSM based on two-photon excitation fluorescence (TPEF) and second harmonic generation (SHG). MPLSM consists of a femtosecond Ti:sapphire laser and a scanning inverted microscope. Several parameters such as the epidermal thickness, the orientation ratio index of collagen bundles (ORICB), the spacing of collagen fibrin as well as the SHG to TPEF index of the dermis (STID) were developed to quantitatively discriminate the sclerodermatous skin from the normal skin. RESULTS: The morphological differences were visualized obviously in the TPEF/SHG images of human skin (normal and sclerodermatous). The values of the developed parameters in normal skin were significantly different from that in sclerodermatous skin (P<0.05). CONCLUSION: MPLSM could discriminate the sclerodermatous skin from the normal skin. With the advent of the clinical portability of typical MPLSM, this technique has great potential for application in the in vivo diagnosis of LS as well as for monitoring the treatment response.


Assuntos
Dermoscopia/métodos , Epiderme/patologia , Microscopia de Fluorescência por Excitação Multifotônica/métodos , Esclerodermia Localizada/patologia , Adulto , Idoso , Colágeno/metabolismo , Dermoscopia/instrumentação , Monitoramento de Medicamentos/métodos , Elasticidade , Epiderme/metabolismo , Feminino , Análise de Fourier , Humanos , Microscopia de Fluorescência por Excitação Multifotônica/instrumentação , Modelos Biológicos
15.
Opt Express ; 16(1): 207-12, 2008 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-18521149

RESUMO

An all-single-mode-fiber L-band superfluorescent fiber source (SFS) with 1 W output power, 34.3 nm bandwidth (FWHM) and 54% optical conversion efficiency is constructed by seeding a high power erbium-doped fiber amplifier (EDFA) with a low power L-band ASE seed source to avoid parasitic lasing. The source is resonantly pumped by a high power C-band SFS peaked at 1545 nm.


Assuntos
Érbio/química , Tecnologia de Fibra Óptica/instrumentação , Lasers , Iluminação/instrumentação , Medições Luminescentes/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Tecnologia de Fibra Óptica/métodos , Iluminação/métodos , Medições Luminescentes/métodos
16.
Opt Express ; 13(5): 1531-6, 2005 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-19495028

RESUMO

An L band superfluorescent fiber source (SFS) with output power of 0.94W is presented, under 4.4W 976nm pump power. The optical conversion efficiency is about 21%. The spectrum covers the broad wavelength range from 1560nm to 1615nm. The high power L band SFS is constructed by a low power L band amplified spontaneous emission (ASE) seed source and a high power erbium-ytterbium co-doped fiber (EYDF) amplifier in double pass forward pumping configuration.

17.
Opt Express ; 13(20): 7878-83, 2005 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-19498816

RESUMO

A branch arm filtering technique is firstly proposed and experimentally demonstrated. A tunable band pass filter is inserted into one branch arm of the Mach-Zehnder type resonator instead of into the common arm as usual, in the coherent combining of two tunable fiber lasers. The arrangement improves the efficiency of the laser without obvious spectral quality penalty. The laser can be tuned from 1530 nm to 1570 nm with little power fluctuation, which is limited by the tuning range of the filter. A novel scaling scheme is also proposed, allowing the technique to be applied to the tuning of an extremely high power laser with a low power filter. The technique is expected to be compatible with other kinds of lasers such as linearly polarized lasers, Michelson type resonator and bulk lasers as well.

18.
Opt Lett ; 29(7): 724-6, 2004 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-15072371

RESUMO

A cw laser-diode-pumped Yb-doped double-clad fiber laser operating in a hybrid Q-switched regime was demonstrated. The output pulses had a duration as short as 4.2 ns, a tunable wavelength range from 1080.8 to 1142.7 nm, and a linewidth of less than 0.05 nm. Maximum peak power of approximately 175 kW and single-pulse energy of 1.57 mJ were obtained.

19.
Opt Lett ; 28(7): 537-9, 2003 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-12696608

RESUMO

A laser-diode-pumped Yb-doped double-clad fiber laser operating in a hybrid Q-switched regime has been demonstrated. With pulsed pump light and stimulated Brillouin scattering of the gain fiber as the Q-switching mechanisms, the laser generated nanosecond pulses with a stable repetition rate. A single-pulse energy of as much as 143.1 microJ with a peak power of 28.6 kW was obtained. Use of an external-cavity diffraction grating in the Littman configuration permitted tuning of the laser wavelength over a 15.7-THz range from 1080 to 1140 nm, and a linewidth of 0.04 nm over the whole tuning range was achieved.

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