2,211 research outputs found
Appearance before Senate Committee testifying on the destruction of poisons developed by the CIA
No full textRichard Helms appears before a Senate Committee testifying on the destruction of poisons developed by the CIA. With the voices of Richard Helms, Howard Baker, Frank Church, Walter Huddleston, Thomas Karamessines, Charles Mathias, Walter Mondale, Robert Morgan, Frederick Schwartz, Richard Schweiker, and John Tower
Hans G Helms – und andere politische Vokalwerke
No full textKonzert mit dem SWR Vokalensemble
im ZKM_Foyer und ZKM_Kubus, 20 Uhr, Eintritt 10/7€ Programm
Luigi Nono »La Fabbrica illuminata« (1964) für Sopran und Tonband (17’)
Hans G Helms »Fa:m' Ahniesgwow« (1959) - Struktur I,1 (7’) Ausschnitt als Tonbandkomposition; Version und Realisation: die sprechbohrer (Sigrid Sachse, Harald Muenz, Georg Sachse), 2009; eine Produktion des Hessischen Rundfunks 2009, Redaktion Neue Musik/Klangkunst, hr2-kultur, Stefan Fricke, Aufnahmetechnik: Thomas Rombach
Herbert Eimert »Epitaph für Aikichi Kuboyama« (1962) 4-Kanal-Tonband (Stimmr: Richard Münch, Realisation: Leopold von Knobelsdorff, Produktion WDR) (23’)
Luigi Nono »¿Dónde estás, hermano?« (1982) für vier Frauenstimmen (6’)
Luigi Nono »Ha venido, Canciones para Silvia« (1960) für Sopran solo und sechsstimmigen Sopranchor
Karl Amadeus Hartmann (1915-1963) »Kantate für sechsstimmigem Männerchor a cappella« (1930) (5’)
I »Kohlenbrot« (Johannes R. Becher)
II »Wir haben eine Welt zu gewinnen« (K. Marx)
Hans G Helms »Konstruktionen für 16 Chorstimmen a cappella« nach Sätzen aus dem Manifest der kommunistischen Partei (1848) von Karl Marx und Friedrich Engels zum 5. Mai 1968 (1968, UA) (15’
Helms Bill Would Eliminate Affirmative Action
No full textNC Sen. Helms has introduced a bill to end all AA
Quantitative magnetization transfer by trains of radio frequency pulses in human brain: extension of a free evolution model to continuous-wave-like conditions
No full textA theoretical model of free evolution between repeated magnetic transfer (MT) pulses was extended to continuous-wave (CW)-like conditions showing that only the repetitive "direct" saturation of bulk water changes the transient and stationary behavior. The influence of the pulse repetition period (PR) on progressive saturation was studied in cortical gray matter (GM) and central white matter (WM) under conditions of short periods of free evolution and strong macromolecular saturation. Interpulse delays of 3 ms were achieved in vivo on a 1.5-T MR system with bell-shaped MT pulses of 12-ms duration and nominal flip angles of up to 1440 degrees and single-shot readout by a stimulated echo acquisition mode localization sequence. The frequency offset was chosen between 1 and 3 kHz to avoid excessive direct saturation. The stationary MT ratio (MTR) followed an inverse linear PR dependence, showing a consistent partial saturation of about 90% at zero PR for both WM and GM. Comparison to a relaxation-matched liquid indicated the presence of MT, but not necessarily of direct saturation. The transient behavior indicated considerable direct saturation, but this could also be explained by MT. These inconsistencies showed that the intervals of time evolution in our experiments were too long to be modeled by CW-like conditions. Free evolution takes place during the whole PR rather than during the interpulse delay only. Quantification using the rates of free evolution theory yielded the saturations and rate constants necessary to explain the observed behavior. The theory of rapid CW-like pulsing provides an upper limit for the rate of progressive saturation. This limit is approached at PR below an estimated value of 5 ms. The phenomenological PR dependence of the steady-state MTR may indicate that MT exceeded the direct saturation. Unlike to an idealized CW experiment, the extrapolated value at zero PR is subject to direct effects and not a physically meaningful constant. (c) 2005 Elsevier Inc. All rights reserved
Simultaneous measurement of saturation and relaxation in human brain by repetitive magnetization transfer pulses
No full textMagnetization transfer (MT) by equidistant pulse trains can be described as being analogous to progressive partial saturation, where 'direct' saturation of water is amplified by MT contributions that are dependent on macromolecular content and differential saturation. This concept was applied to study the transition to steady state in the human brain using similar MT-pulses as in imaging. Up to 41 bell-shaped MT-pulses of 12 ms duration were applied at frequency offsets between 0.5 and 15 kHz with flip angles between 1080 and 1440degrees. Central white and parietal gray matter was studied in human subjects using STEAM for localized read-out (TE = 30 ms, TM = 13.7 ms). The apparent degree of saturation, delta(app), and the longitudinal relaxation of the water pool during the pulse repetition period (PR) were fitted to the transient behavior after signal correction for cerebro-spinal fluid. PR was varied between 15 and 100 ms to assess the PR-dependence of the fitted parameters. The MT-term in delta(app) exceeded the direct saturation and attained its maximum at PR greater than or equal to 100 ms. The macromolecular pool was only partially saturated by a single MT-pulse. The offset may be increased to 2.5 kHz to reduce direct saturation without sacrificing NIT in white matter. The estimated relaxation rates (1.04 +/- 0.11 s(-1) in WM; 0.76 +/- 0.13 s(-1) in GM) were faster than are commonly observed at 1.5 T. The apparent saturation is a measure for MT that is not confounded by relaxation. To maximize MT in brain tissue, MT-pulses should be applied at PR 100 ms or longer. At shorter PR, a larger steady state satuation is obtained at the cost of increased contributions from direct saturation. Since this accelerates the convergence, PR should be decreased to reach the steady state within a specified time. A faster transition can always be achieved at a reduced frequency offset via increased direct saturation. Copyright (C) 2004 John Wiley Sons, Ltd
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