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Puh! 10% Fehlerquote beim Geschlecht? Hier fehlt wohl eine Angabe zu Entscheidungszeit oder Alter. Die Erkennungsrate des Menschen bei Babys duerfte wahrscheinlich gegen Null gehen. Wenn man so auf 10% kommt...
hoppla, da ist uns ein Fehler durchgerutscht. Mit Penicillin kann man natürlich nicht impfen, es ging um eine flächendeckende Behandlung von Infektionskrankheiten.
Also, dass mit Penicillin geimpft werden kann, ist mir wirklich neu. Habe ich da im Pharmazie-Studium was verpasst?!! Spaß beiseite, der Übertragungsweg scheint mir zwar plausibel, aber warum sollte das SIV ausgerechnet dadurch anfangen zu mutieren? Ungeschützten Geschlechtsverkehr hat er mit Sicherheit auch in den 50er Jahren schon gegeben, und damit auch eine Übertragung von Mensch zu Mensch.
Ich bin ja nun kein Arzt, aber wie kann mit Penicillin eine Impfwirkung erreichen? Muss da nicht der abgeschwächte oder leicht veränderte Virus gespritzt werden, um die Bildung von Antikörpern zu aktivieren?
Meines Wissens hat man HI-Viren in Präparaten von Menschen gefunden, die vor 1950 verstorben sind. Ich meine mich an eine Meldung erinnern zu können, in der u.a. von einem 1927 in Großbritannien verstorbenen Seemann gelesen zu haben.
EFFICIENT CONVERSION OF HEAT TO ELECTRICITY WITH THERMAL DIODES
Two physical effects that improve the efficiency of a thermoelectric material for converting heat into electricity were reported by P. L. Hagelstein and Y. Kucherov. When a temperature gradient is placed across a thermoelectric material, an open-circuit voltage is induced which is proportional to the material thermopower. A highly doped emitter layer added to the high-temperature side of a weakly doped thermoelectric material (creating a thermal diode) was found to increase the open-circuit voltage by as much as a factor of 2.8 due to a thermionic injection effect. This effect was observed in indium antimonide devices and in mercury cadmium telluride devices. An addition open-circuit voltage increase was observed following the introduction of a compensation layer near the cold-side contact. This effect is attributed to a blockage of the ohmic return current that balances the internal forward thermoelectric and thermionic currents under zero-current conditions. This effect was seen to increase the voltage by about 50%. These two mechanisms can be used to greatly increase the efficiency of energy conversion.
Research on thermoelectric energy conversion generally has focused on finding or developing materials with a large Seebeck coefficient, high electrical conductivity, and low thermal conductivity. The new results indicates that the performance of a good thermoelectric semiconductor can be greatly enhanced by the addition of emitter layers and compensation layers, so that the resulting conversion efficiency is no longer limited in the same way by the material parameters. For example, an enhancement of the effective figure of merit for Hg.86Cd.14Te in one experiment was about a factor of 8 above the thermoelectric result, and is due to thermionic injection.
The ideas behind the thermal diode come from a variety of disciplines. Vacuum thermionic converters can be very efficient, but require temperatures on the order of 1000 ºC at the hot side to obtain significant thermionic currents. Using a solid state implementation of the basic scheme provided a way to maintain the good features of the vacuum thermionic scheme, while lowering the operating temperature, since the work function could be made to be much less, as was proposed by Gerald Mahan. In earlier work, strong thermionic effects were noted when the electron transport was ballistic, as in the vacuum thermionic case. In the thermal diode, the electron transport is ballistic across a narrow potential barrier, but diffusive across the semiconductor gap region. This makes for a much more practical implementation. The notion that the ohmic return current could be blocked comes originally from the ideas behind the Ebers-Moll model for the bipolar junction transistor.
RE: Penicillin-Impfung?
17.12.2001, Friedrich Rückert"Entstehung von HIV"
"Impfung"
Voll daneben
14.12.2001, Torsten LangeRE: Penicillin-Impfung?
14.12.2001, Antje Findeklee, Redaktionhoppla, da ist uns ein Fehler durchgerutscht. Mit Penicillin kann man natürlich nicht impfen, es ging um eine flächendeckende Behandlung von Infektionskrankheiten.
Danke für den Hinweis!
Mit freundlichen Grüßen
Antje Findeklee, Redaktion
RE: RE: Schlichtheit siegt!
13.12.2001, TanzbeaPenicillin-Impfung?
13.12.2001, Jutta PaulusHabe ich da im Pharmazie-Studium was verpasst?!!
Spaß beiseite, der Übertragungsweg scheint mir zwar plausibel,
aber warum sollte das SIV ausgerechnet dadurch anfangen zu mutieren?
Ungeschützten Geschlechtsverkehr hat er mit Sicherheit auch in den
50er Jahren schon gegeben, und damit auch eine Übertragung von Mensch zu Mensch.
RE: Schlichtheit siegt!
13.12.2001, Karl BihlmeierPenicillin-Impfung
13.12.2001, J. AndreshHI-Viren gab es schon früher
13.12.2001, Mag. Dipl.Ing. Wilhelm HorakIch meine mich an eine Meldung erinnern zu können, in der u.a. von einem 1927
in Großbritannien verstorbenen Seemann gelesen zu haben.
Schlichtheit siegt!
13.12.2001, Christian GüntherDas vermeidet unnötiges Suchen und Fluchen!
Hallo ihr Biofreunde
11.12.2001, HALLORE: Fehler ?
11.12.2001, J. Schüring... oh ja, es soll! Das Maunder-Minimum dauerte in der Tat von 1645 bis 1715. Danke für den Hinweis.
Mit freundlichen Grüßen
J. Schüring, Redaktion
Fehler ?
11.12.2001, KARL BEDNARIKSollte :
"von der Mitte des 16. Jahrhunderts an"
nicht heißen :
"von der Mitte des 17. Jahrhunderts an"
???
RE:macht die augen auf das sind keine Kraken
09.12.2001, ken aus berlinRE: Elektrische Energie aus Wärme: Wirkungsgrad
09.12.2001, bopTwo physical effects that improve the efficiency of a thermoelectric material for converting heat into electricity were reported by P. L. Hagelstein and Y. Kucherov. When a temperature gradient is placed across a thermoelectric material, an open-circuit voltage is induced which is proportional to the material thermopower. A highly doped emitter layer added to the high-temperature side of a weakly doped thermoelectric material (creating a thermal diode) was found to increase the open-circuit voltage by as much as a factor of 2.8 due to a thermionic injection effect. This effect was observed in indium antimonide devices and in mercury cadmium telluride devices. An addition open-circuit voltage increase was observed following the introduction of a compensation layer near the cold-side contact. This effect is attributed to a blockage of the ohmic return current that balances the internal forward thermoelectric and thermionic currents under zero-current conditions. This effect was seen to increase the voltage by about 50%. These two mechanisms can be used to greatly increase the efficiency of energy conversion.
Research on thermoelectric energy conversion generally has focused on finding or developing materials with a large Seebeck coefficient, high electrical conductivity, and low thermal conductivity. The new results indicates that the performance of a good thermoelectric semiconductor can be greatly enhanced by the addition of emitter layers and compensation layers, so that the resulting conversion efficiency is no longer limited in the same way by the material parameters. For example, an enhancement of the effective figure of merit for Hg.86Cd.14Te in one experiment was about a factor of 8 above the thermoelectric result, and is due to thermionic injection.
The ideas behind the thermal diode come from a variety of disciplines. Vacuum thermionic converters can be very efficient, but require temperatures on the order of 1000 ºC at the hot side to obtain significant thermionic currents. Using a solid state implementation of the basic scheme provided a way to maintain the good features of the vacuum thermionic scheme, while lowering the operating temperature, since the work function could be made to be much less, as was proposed by Gerald Mahan. In earlier work, strong thermionic effects were noted when the electron transport was ballistic, as in the vacuum thermionic case. In the thermal diode, the electron transport is ballistic across a narrow potential barrier, but diffusive across the semiconductor gap region. This makes for a much more practical implementation. The notion that the ohmic return current could be blocked comes originally from the ideas behind the Ebers-Moll model for the bipolar junction transistor.
Neadretaler als Vorfahre?
06.12.2001, Markus Sacher