Optical Tweezers
Mostrando 1-12 de 48 artigos, teses e dissertações.
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1. Allyl Dibenzoylmethane Derivative: Antimelanoma Activity and Study of Its Molecular Mechanism of Interaction with DNA
In this study, we assessed the cytotoxic effect of 1,3-diphenyl-2-allyl-1,3-propanedione (DPAP) on B16F10 and Tm5 melanoma cells and investigated its interaction with DNA (deoxyribonucleic acid) using optical tweezers. The compound showed to be effective against B16F10 cells with selectivity index (SI) of 7.92 and interaction to the outer surface of the doub
J. Braz. Chem. Soc.. Publicado em: 2021-07
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2. Biomechanical and biochemical investigation of erythrocytes in late stage human leptospirosis
Leptospirosis is a zoonotic disease caused by bacteria of the genus Leptospira, which can cause lipid changes in the erythrocyte membrane. Optical tweezers were used to characterize rheological changes in erythrocytes from patients with leptospirosis in the late stage. Biochemical methods were also used for quantification of plasma lipid, erythrocyte membran
Braz J Med Biol Res. Publicado em: 2020-08
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3. Teoria e calibração de pinças ópticas / Theory and calibration of optical tweezers
Neste trabalho estudamos alguns aspectos físicos do pinçamento óptico. Usamos um método de calibração da pinça óptica via análise da função de autocorrelação da posição da microesfera; por meio deste é possível determinar a constante de força da pinça de duas maneiras: usando a amplitude e o tempo característico desta função. Verificamo
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 16/02/2012
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4. Localized beams in optical tweezers with conventional and metamaterial particles / Feixes localizados em pinças opticas com particulas convencionasi e metamateriais
In this thesis, we explore some applications of localized beams in FSO - Free Space Optics - and optical tweezers, greater emphasis been given to the second one. For FSO, we show that it is possible to choose the desired longitudinal intensity pattern by using optical elements adequately modeled in their phase functions: the axicons. In this way, these beams
Publicado em: 2009
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5. Estudo das propriedades eletricas das hemacias utilizando pinça optica / Study of electrical properties of red blood cell using optical tweezers
The red blood cell (RBC) membrane contains proteins and glycoproteins embedded in a fluid lipid bilayer that confers viscoelastic behavior. Sialylated glycoproteins of the RBC membrane are responsible for a negatively charged surface, which creates a repulsive electric zeta potential (Z) between the cells.The compact layer of charge or Stern consists of ions
Publicado em: 2009
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6. Ferramenta biofotonica integrada para manipulações e microscopias confocais / Integrates biophotonic tool for manipulations and confocal microscopies
The research in biomedical photonics is clearly evolving in the direction of the understanding of biological processes at the cell level. The spatial resolution to accomplish this task practically requires photonics tools. However, an integration of different photonic tools and a multimodal and functional approach will be necessary to access the mechanical a
Publicado em: 2007
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7. Desenvolvimento de metodologia de medida vetorial das forças em tempo real de microorganismos utilizando ponças opticas para estudos de quimiotaxia e osmotaxia de parasita / Development of methodology vectorial measurements of forces in real time of microorganisms using optical tweezers for chemotaxis and osmotaxis studies of parasites
Unicellular microorganisms, like others live beings, need to interact with environment to find nourishment. They have only hydrodynamics sensors and biochemical receptors on membrane to accomplish this task. The response of the microorganism to concentration gradients of attractive or repulsive chemical substances is called chemotaxis. The investigation of c
Publicado em: 2007
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8. Força optica em pinças opticas : estudo teorico e experimental / Optical force in optical tweezers : theory and experiment
The optical tweezers is an instrument capable of manipulating and trapping dielectric particles through the radiation pressure. Their applications in the life sciences and biophysics increased exponentially after it has been demonstrated that it allowed to microorganisms to be maintained alive trapped for long times. Information obtained from these experimen
Publicado em: 2006
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9. Análise do potencial de calibração da força óptica através de dispositivos de microscopia de força atômica / Analysis of the calibration potential of optical force through atomic force microscopy devices
O microscópio de força atômica é uma ferramenta que possibilita a medida de forças precisamente localizadas com resoluções no tempo, espaço e força jamais vistas. No coração deste instrumento está um sensor a base de uma viga (cantilever) que é responsável pelas características fundamentais do AFM. O objetivo desta pesquisa foi usar a deflexã
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 19/12/2005
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10. Sistema de micromanipulação e microanalise com pinças oticas / Micromanipulation and microanalysis in an optical tweezers systems
Not informed
Publicado em: 2004
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11. Aplicação da pinça optica para o estudo da deformabilidade das hemacias
The deformability of erythrocytes is a critical determinant of blood flow in microcirculation. By capturing red blood cells with optical tweezers and dragging them through a viscous fluid we were able to measure their overall elasticity. Laser optical tweezers, based on photon momentum transfer, have been used successfully in a variety of biological applicat
Publicado em: 2003
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12. Measurement of Adhesive Forces between Individual Staphylococcus aureus MSCRAMMs and Protein-Coated Surfaces by Use of Optical Tweezers
The force required to rupture bonds between individual Staphylococcus aureus MSCRAMMs and surfaces coated with extracellular matrix molecules has been quantified by using optical tweezers. The observed binding forces between fibrinogen or fibronectin and S. aureus MSCRAMMs occurred as an approximate integer multiple of 20 or 25 pN, respectively.
American Society for Microbiology.