338 research outputs found
Colony Assay for Antibody Library Screening: Outlook and Comparison to Display Screening
Recombinant monoclonal antibodies are established by screening the antibody libraries. To obtain antibodies with a high specificity and affinity, an efficient screening process with a highly diverse library including low background signals is necessary. One of the most extensively used methods is the phage display method. Although phage display screening is a powerful tool for enriching clones from vast libraries, it is not easy to identify single clones with an antigen recognition function only through several rounds of biopanning. The application of colony assays for screening antibody libraries can identify clones with a high reliability by a direct observation of the antibody-antigen binding during the screening process; however, the size of the library that can be dealt with is limited. This chapter describes the colony assay as a current screening technology used in recombinant monoclonal antibody production, the possible problems in this method, and discusses the outlook for this technology
An ytterbium quantum gas microscope with narrow-line laser cooling
We demonstrate site-resolved imaging of individual bosonic
atoms in a Hubbard-regime two-dimensional optical lattice
with a short lattice constant of 266 nm. To suppress the heating by probe light
with the - transition of the wavelength = 399 nm for
high-resolution imaging and preserve atoms at the same lattice sites during the
fluorescence imaging, we simultaneously cool atoms by additionally applying
narrow-line optical molasses with the - transition of the
wavelength = 556 nm. We achieve a low temperature of $T = 7.4(1.3)\
\mu\mathrm{K}$, corresponding to a mean oscillation quantum number along the
horizontal axes of 0.22(4) during imaging process. We detect on average 200
fluorescence photons from a single atom within 400 ms exposure time, and
estimate the detection fidelity of 87(2)%. The realization of a quantum gas
microscope with enough fidelity for Yb atoms in a Hubbard-regime optical
lattice opens up the possibilities for studying various kinds of quantum
many-body systems such as Bose and Fermi gases, and their mixtures, and also
long-range-interacting systems such as Rydberg states.Comment: 14 pages, 6 figure
Resonant Control of Interaction Between Different Electronic States
We observe a magnetic Feshbach resonance in a collision between the ground
and metastable states of two-electron atoms of ytterbium (Yb). We measure the
on-site interaction of doubly-occupied sites of an atomic Mott insulator state
in a three-dimensional optical lattice as a collisional frequency shift in a
high-resolution laser spectroscopy. The observed spectra are well fitted by a
simple theoretical formula, in which two particles with an s-wave contact
interaction are confined in a harmonic trap. This analysis reveals a wide
variation of the interaction with a resonance behavior around a magnetic field
of about 1.1 Gauss for the energetically lowest magnetic sublevel of
Yb, as well as around 360 mG for the energetically highest magnetic
sublevel of Yb. The observed Feshbach resonance can only be induced
by an anisotropic inter-atomic interaction. This novel scheme will open the
door to a variety of study using two-electron atoms with tunable interaction.Comment: 5 pages, 5 figure
Effects of laser wavelength and density scalelength on absorption of ultrashort intense lasers on solid-density targets
Hot electron temperatures and electron energy spectra in the course of
interaction between intense laser pulse and overdense plasmas are reexamined
from a viewpoint of the difference in laser wavelength. The hot electron
temperature measured by a particle-in-cell simulation is scaled by rather
than at the interaction with overdense plasmas with fixed ions,
where and are the laser intensity and wavelength, respectively.Comment: 12th International Congress on Plasma Physics, 25-29 October 2004,
Nice (France
A New Find of a Prboscidean Fossil from Nagano Prefecture, Central Japan
Article信州大学理学部紀要 6(1): 37-44(1971)departmental bulletin pape
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