6,774 research outputs found

    An optical phase-locking with large and tunable frequency difference based on vertical-cavity surface-emitting laser

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    We present a novel technique to phase-lock two lasers with controllable frequency difference. In our setup, one sideband of a current modulated Vertical-Cavity Surface-Emitting Laser (VCSEL) is phase locked to the master laser by injection seeding, while another sideband of the VCSEL is used to phase lock the slave laser. The slave laser is therefore locked in phase with the master laser, with a frequency difference tunable up to about 35 GHz. The sideband suppression rate of the slave laser is more than 30dB at 30 uW seed power. The heterodyne spectrum between master and slave has a linewidth of less than 1 Hz. A coherent population trapping resonance of rubidium is achieved using such beams.Comment: 4 pages, 4 Encapsulated PostScript figure

    Influenza virus antigenic variation, host antibody production and new approach to control epidemics

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    Influenza is an infectious disease and can lead to life-threatening complications like pneumonia. The disease is caused by three types of RNA viruses called influenza types A, B and C, each consisting of eight negative single-stranded RNA-segments encoding 11 proteins. Current annual vaccines contain two type A strains and one type B strain and are capable of inducing strong antibody responses to both the surface glycoprotein hemagglutinin and the neuraminidase. While these vaccines are protective against vaccine viruses they are not effective against newly emerging viruses that contain antigenic variations known as antigenic drift and shift. In nature, environmental selection pressure generally plays a key role in selecting antigenic changes in the antigen determining spots of hemagglutinin, resulting in changes in the antigenicity of the virus. Recently, a new technology has been developed where influenza-specific IgG+ antibody-secreting plasma cells can be isolated and cloned directly from vaccinated humans and high affinity monoclonal antibodies can be produced within several weeks after vaccination. The new technology holds great promise for the development of effective passive antibody therapy to limit the spread of influenza viruses in a timely manner

    Influenza virus antigenic variation, host antibody production and new approach to control epidemics

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    Influenza is an infectious disease and can lead to life-threatening complications like pneumonia. The disease is caused by three types of RNA viruses called influenza types A, B and C, each consisting of eight negative single-stranded RNA-segments encoding 11 proteins. Current annual vaccines contain two type A strains and one type B strain and are capable of inducing strong antibody responses to both the surface glycoprotein hemagglutinin and the neuraminidase. While these vaccines are protective against vaccine viruses they are not effective against newly emerging viruses that contain antigenic variations known as antigenic drift and shift. In nature, environmental selection pressure generally plays a key role in selecting antigenic changes in the antigen determining spots of hemagglutinin, resulting in changes in the antigenicity of the virus. Recently, a new technology has been developed where influenza-specific IgG+ antibody-secreting plasma cells can be isolated and cloned directly from vaccinated humans and high affinity monoclonal antibodies can be produced within several weeks after vaccination. The new technology holds great promise for the development of effective passive antibody therapy to limit the spread of influenza viruses in a timely manner

    Strong Convergence Theorems for Mixed Equilibrium Problem and Asymptotically I

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    This paper aims to use a hybrid algorithm for finding a common element of a fixed point problem for a finite family of asymptotically nonexpansive mappings and the set solutions of mixed equilibrium problem in uniformly smooth and uniformly convex Banach space. Then, we prove some strong convergence theorems of the proposed hybrid algorithm to a common element of the above two sets under some suitable conditions
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