827 research outputs found
Local SiC photoluminescence evidence of non-mutualistic hot spot formation and sub-THz coherent emission from a rectangular BiSrCaCuO mesa
From the photoluminescence of SiC microcrystals uniformly covering a
rectangular mesa of the high transition temperature superconductor
BiSrCaCuO, the local surface temperature
was directly measured during simultaneous sub-THz emission from the
intrinsic Josephson junctions (IJJs) in the mesa. At high bias currents and
low bath temperatures K, the center of a large
elliptical hot spot with jumps dramatically with little
current-voltage characteristic changes. The hot spot doesn't alter the
ubiquitous primary and secondary emission conditions: the ac Josephson relation
and the electromagnetic cavity resonance excitation, respectively. Since the
intense sub-THz emission was observed for high K in
the low bias regime where hot spots are absent, hot spots can not provide
the primary mechanisms for increasing the output power, the tunability, or for
promoting the synchronization of the IJJs for the sub-THz emission, but can
at best coexist non-mutualistically with the emission. No standing
waves were observed
Hautgeschwulste durch Lungendistoma (Paragonimus westermani)
Zwei 7 jahrige Kinder nahmen ungekochte Flussigkeit von Potamon dehaanii zu sich, eine Volksrnedizin gegen Keuchhusten. Einige Monate darauf bemerkten sie blutige Sputa und nicht entzundliche Geschwulste an den Lenden oder der Bauchseite. In den Tumoren wurde je ein Lungendistoma entdeckt. Dieser Parasit kann daher manchmal in die Subkutis oder in die tiefe Kutisschicht einwandern. Zum Schlusse Inochten wir Herrn Prof. Tanabe vom pathologischen Institut dieser Universitat unsern warmsten Dank aussprechen dafur, dass er die Struktur der Parasiten eingehend untersuchte. </p
On-Demand Density Correction Using Steady-State Plasmas in the LHD Thomson Scattering
In order to measure reliable electron densities of fusion plasmas by using Thomson scattering system, both accurate absolute calibration and long-term stability in the system are required. Even if slight misalignment of some optics occurs, it may cause large errors in measured densities. We propose a new method to obtain correctionfactors to the errors originated from misalignment by using steady-state plasma discharges. In addition to the datacorrection, realignment of the laser beam can be applied als
A bacterial platform for fermentative production of plant alkaloids
The secondary metabolites of higher plants include diverse chemicals, such as alkaloids, isoprenoids and phenolic compounds (phenylpropanoids and flavonoids). Although these compounds are widely used in human health and nutrition, at present they are mainly obtained by extraction from plants and extraction yields are low because most of these metabolites accumulate at low levels in plant cells. Recent advances in synthetic biology and metabolic engineering have enabled tailored production of plant secondary metabolites in microorganisms, but these methods often require the addition of expensive substrates. Here we develop an Escherichia coli fermentation system that yields plant alkaloids from simple carbon sources, using selected enzymes to construct a tailor-made biosynthetic pathway. In this system, engineered cells cultured in growth medium without additional substrates produce the plant benzylisoquinoline alkaloid, (S)-reticuline (yield, 46.0 mg l−1 culture medium). The fermentation platform described here offers opportunities for low-cost production of many diverse alkaloids
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