scholarly journals Proof-of-principle Experiment of 4He Excimer Cluster Generation via Neutron-3He Absorption Reaction for Visualization of Velocity Fields in Superfluid 4He

hamon ◽  
2020 ◽  
Vol 30 (4) ◽  
pp. 192-196
Author(s):  
T. Matsushita ◽  
V. Sonnenschein ◽  
T. Iguchi ◽  
D. Ito ◽  
M. Kitaguchi ◽  
...  
Keyword(s):  
Velocity Fields ◽  
Cluster Generation ◽  
Proof Of Principle

C. The Continuous Spectrum of Pulsating Variable Stars

1967 ◽  
Vol 28 ◽  
pp. 177-206
Author(s):  
J. B. Oke ◽  
C. A. Whitney
Keyword(s):  
Continuous Spectrum ◽  
Variable Stars ◽  
Velocity Fields ◽  
The Other ◽  
Line Spectrum ◽  
Direct Information ◽  
Thermodynamic Structure ◽  
Diagnostic Interpretation ◽  
Pulsating Variable Stars ◽  
The Continuum

Pecker:The topic to be considered today is the continuous spectrum of certain stars, whose variability we attribute to a pulsation of some part of their structure. Obviously, this continuous spectrum provides a test of the pulsation theory to the extent that the continuum is completely and accurately observed and that we can analyse it to infer the structure of the star producing it. The continuum is one of the two possible spectral observations; the other is the line spectrum. It is obvious that from studies of the continuum alone, we obtain no direct information on the velocity fields in the star. We obtain information only on the thermodynamic structure of the photospheric layers of these stars–the photospheric layers being defined as those from which the observed continuum directly arises. So the problems arising in a study of the continuum are of two general kinds: completeness of observation, and adequacy of diagnostic interpretation. I will make a few comments on these, then turn the meeting over to Oke and Whitney.

The Interpretation of Line Profiles

1977 ◽  
Vol 36 ◽  
pp. 191-215
Author(s):  
G.B. Rybicki
Keyword(s):  
Magnetic Fields ◽  
Atomic Physics ◽  
Velocity Fields ◽  
Spectral Lines ◽  
Inhomogeneous Structure ◽  
The Sun ◽  
Line Profiles ◽  
Physical Phenomena

Observations of the shapes and intensities of spectral lines provide a bounty of information about the outer layers of the sun. In order to utilize this information, however, one is faced with a seemingly monumental task. The sun’s chromosphere and corona are extremely complex, and the underlying physical phenomena are far from being understood. Velocity fields, magnetic fields, Inhomogeneous structure, hydromagnetic phenomena – these are some of the complications that must be faced. Other uncertainties involve the atomic physics upon which all of the deductions depend.

Central kiloparsec of NGC 1326 observed with SINFONI

2020 ◽  
Vol 638 ◽  
pp. A53
Author(s):  
Nastaran Fazeli ◽  
Gerold Busch ◽  
Andreas Eckart ◽  
Françoise Combes ◽  
Persis Misquitta ◽  
...  
Keyword(s):  
Black Hole ◽  
Galaxy Evolution ◽  
Near Infrared ◽  
Velocity Fields ◽  
Molecular Gas ◽  
Nearby Galaxy ◽  
Stellar Content ◽  
Stellar Rotation ◽  
Supermassive Black Hole ◽  
Integral Field Spectrograph

Gas inflow processes in the vicinity of galactic nuclei play a crucial role in galaxy evolution and supermassive black hole growth. Exploring the central kiloparsec of galaxies is essential to shed more light on this subject. We present near-infrared H- and K-band results of the nuclear region of the nearby galaxy NGC 1326, observed with the integral-field spectrograph SINFONI mounted on the Very Large Telescope. The field of view covers 9″ × 9″ (650 × 650 pc2). Our work is concentrated on excitation conditions, morphology, and stellar content. The nucleus of NGC 1326 was classified as a LINER, however in our data we observed an absence of ionised gas emission in the central r ∼ 3″. We studied the morphology by analysing the distribution of ionised and molecular gas, and thereby detected an elliptically shaped, circum-nuclear star-forming ring at a mean radius of 300 pc. We estimate the starburst regions in the ring to be young with dominating ages of < 10 Myr. The molecular gas distribution also reveals an elongated east to west central structure about 3″ in radius, where gas is excited by slow or mild shock mechanisms. We calculate the ionised gas mass of 8 × 105 M⊙ completely concentrated in the nuclear ring and the warm molecular gas mass of 187 M⊙, from which half is concentrated in the ring and the other half in the elongated central structure. The stellar velocity fields show pure rotation in the plane of the galaxy. The gas velocity fields show similar rotation in the ring, but in the central elongated H2 structure they show much higher amplitudes and indications of further deviation from the stellar rotation in the central 1″ aperture. We suggest that the central 6″ elongated H2 structure might be a fast-rotating central disc. The CO(3–2) emission observations with the Atacama Large Millimeter/submillimeter Array reveal a central 1″ torus. In the central 1″ of the H2 velocity field and residual maps, we find indications for a further decoupled structure closer to a nuclear disc, which could be identified with the torus surrounding the supermassive black hole.

Zellersatztherapie beim Morbus Parkinson

2005 ◽  
Vol 24 (01) ◽  
pp. 36-40
Author(s):  
A. Storch ◽  
J. Schwarz
Keyword(s):  
Morbus Parkinson ◽  
Kontrollierte Studien ◽  
Proof Of Principle

ZusammenfassungDer Ersatz dopaminerger Neurone bei Patienten mit Morbus Parkinson bleibt eine attraktive Behandlungsstrategie. Die Implantation von embryonalem Mittelhirngewebe war die erste Therapie, die nicht nur den »Proof-of-Principle« in Tierversuchen lieferte, sondern auch Eingang in klinische Applikationen fand. 1987 wurde zunächst eine Reihe von kleinen offenen Studien mit sorgfältiger Patientenselektion gestartet, die sehr ermutigende Ergebnisse bei zumindest einem Teil der Patienten erbrachten. In den vergangenen Jahren wurden in den USA zwei doppelblinde, kontrollierte Studien abgeschlossen, deren Resultate eher enttäuschend blieben, da die primären Endpunkte (Besserung der Parkinson-Symptomatik im Off) keine signifikanten Unterschiede zeigten. Zudem wurden in beiden Studien 12 Stunden nach L-Dopa-Einnahme Dyskinesien beobachtet. Die Ursachen dieser unterschiedlichen Ergebnisse könnten in der Variabilität des Gewebes, relevanten Immunreaktionen und ungleichmäßiger Dopaminausschüttung im Striatum liegen. Zudem legen die ethischen Probleme bei der Gewinnung des Gewebes die Notwendigkeit anderer, besser standardisierter Gewebe nahe. Derzeit scheint es möglich, dass alternativ sowohl aus embryonalen als auch neuralen Stammzellen, vielleicht sogar aus körpereigenen mesenchymalen Stammzellen dopaminerge Neurone generiert werden könnten. Diese Zellen können über einen langen Zeitraum expandiert, ausreichend standardisiert und charakterisiert werden.

Cluster Generation and Network Component Insertion for Topology Synthesis of Application-Specific Network-on-Chips

2012 ◽  
Vol E95-C (4) ◽  
pp. 534-545 ◽  
Author(s):  
Wei ZHONG ◽  
Takeshi YOSHIMURA ◽  
Bei YU ◽  
Song CHEN ◽  
Sheqin DONG ◽  
...  
Keyword(s):  
Cluster Generation ◽  
Application Specific ◽  
Network Component

Enantioselective Multi-Component Cyclopropane Synthesis Enabled by Cu-Catalyzed Cyclopropene Carbometallation with Organoboron Reagent

2018 ◽  
Author(s):  
Zhanyu Li ◽  
Mengru Zhang ◽  
Yu Zhang ◽  
Shuang Liu ◽  
Jinbo Zhao ◽  
...  
Keyword(s):  
Carbon Source ◽  
Stereoselective Synthesis ◽  
Organometallic Reagents ◽  
Preliminary Results ◽  
Quaternary Center ◽  
Chiral Centers ◽  
Substituted Cyclopropanes ◽  
Proof Of Principle

Deployment of organoboron in lieu of the strongly basic <br>organometallic reagents as carbon source in Cu-catalyzed <br>cyclopropene carbometallation opens unprecedented three-<br>component reactivity for stereoselective synthesis of poly-substituted cyclopropanes. A proof-of-principle demonstration of this novel carbometallation strategy is presented herein for a highly convergent access to poly-substituted aminocyclopropane framework via <br>carboamination. Preliminary results on asymmetric desymmetrization with commercial bisphosphine ligands attained high levels of enantioselection, offering a straightforward access to enantioenriched aminocyclopropanes bearing all-three chiral centers, including an all-carbon quaternary center. This strategy may underpin a host of novel synthetic protocols for poly-substituted cyclopropanes. <br>

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