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A significant fraction of the energy density of the interstellar medium is in the form of high-energy charged particles (cosmic rays) 1 . The origin of these particles remains uncertain. Although it is generally accepted that the only sources capable of supplying the energy required to accelerate the bulk of Galactic cosmic rays are supernova explosions, and even though the mechanism of particle acceleration in expanding supernova remnant (SNR) shocks is thought to be well understood theoretically 2 , 3 , unequivocal evidence for the production of high-energy particles in supernova shells has proven remarkably hard to find. Here we report on observations of the SNR RX J1713.7 - 3946 (G347.3 - 0.5), which was discovered by ROSAT 4 in the X-ray spectrum and later claimed as a source of high-energy γ-rays 5 , 6 of TeV energies (1 TeV = 10 12  eV). We present a TeV γ-ray image of the SNR: the spatially resolved remnant has a shell morphology similar to that seen in X-rays, which demonstrates that very-high-energy particles are accelerated there. The energy spectrum indicates efficient acceleration of charged particles to energies beyond 100 TeV, consistent with current ideas of particle acceleration in young SNR shocks.

Very high energy γ-rays probe the long-standing mystery of the origin of cosmic rays. Produced in the interactions of accelerated particles in astrophysical objects, they can be used to image cosmic particle accelerators. A first sensitive survey of the inner part of the Milky Way with the High Energy Stereoscopic System (HESS) reveals a population of eight previously unknown firmly detected sources of very high energy γ-rays. At least two have no known radio or x-ray counterpart and may be representative of a new class of \"dark\" nucleonic cosmic ray sources.

Faced with limited resources, schools require tools that increase the accuracy and efficiency of functional behavioral assessment. Yarbrough and Carr (2000) provided evidence that informant confidence ratings of the likelihood of problem behavior in specific situations offered a promising tool for predicting the accuracy of function-based hypotheses developed from staff interviews. The current study evaluated conditions in which a similar rating of informant confidence was effective in predicting the accuracy of functional assessment hypothesis statements. Nine students with problem behavior were identified, and functional behavioral assessment interviews with confidence scores were completed with 58 staff members. Between five and eight adults were interviewed about each student. The adults were selected based on their range of contact with the student (0 to 10+ hours per week) and their self-assessed knowledge about behavioral theory (no knowledge to extensive knowledge). Functional analyses were conducted to assess agreement with functional assessment hypotheses and the predictive value of confidence ratings. Results suggested limitations to the general use of confidence ratings in distinguishing accurate from inaccurate functional hypotheses across school staff with a broad range of contact with the target student. The study did find that informants who were both highly confident and who identified accurate functional assessment hypotheses had significantly higher levels of contact with the student in the target routine than those informants who had low confidence ratings and/or identified an incorrect function for the problem behavior.

Using the HERA-B detector, the b (b) over bar production cross section has been measured in 920 GeV proton collisions on carbon and titanium targets. The b (b) over bar production was tagged via inclusive bottom quark decays into J/psi by exploiting the longitudinal separation of J/psi --> l(+)l(-) decay vertices from the primary proton-nucleus interaction. Both e(+)e(-) and mu(+)mu(-) channels have been reconstructed and the combined analysis yields the cross section sigma(b (b) over bar) = 32(-12)(+14)(stat) (+6)(-7)(sys) nb/nucleon.

Inclusive differential cross sections dsigma(pA)/dx(F) and dsigma(pA)/dp(t)(2) for the production of K-S(0), Lambda, and (&ULambda;) over bar particles are measured at HERA in proton-induced reactions on C, Al, Ti, and W targets. The incident beam energy is 920 GeV, corresponding to roots = 41.6 GeV in the proton-nucleon system. The ratios of differential cross sections dsigma(pA)(K-S(0))/dsigma(pA)(Lambda) and dsigma(pA)((&ULambda;) over bar)/dsigma(pA) (Lambda) are measured to be 6.2 +/- 0.5 and 0.66 +/- 0.07, respectively, for x(F) approximate to -0.06. No significant dependence upon the target material is observed. Within errors, the slopes of the transverse momentum distributions da,Ald t also show no significant dependence upon the target material. The dependence of the extrapolated total cross sections sigma(pA) on the atomic mass A of the target material is discussed, and the deduced cross sections per nucleon sigma(pN) are compared with results obtained at other energies.

Die Schwangerschaftscholestase („intrahepatic cholestasis of pregnancy“, ICP) ist die häufigste schwangerschaftsspezifische Lebererkrankung. Das Leitsymptom Juckreiz sowie eine begleitende Serumkonzentrationserhöhung von Gallensäuren und/oder der Alaninaminotransferase (ALT) sind wegweisend in der Diagnosestellung. Die mütterliche Prognose ist gut. Das fetale Outcome ist abhängig von der Gallensäurenkonzentration. Die ICP ist dabei sowohl mit Frühgeburt als auch mit intrauterinem Fruchttod (IUFT) assoziiert. Dieser ist Folge einer akuten fetalen Asphyxie, nicht einer chronischen uteroplazentaren Dysfunktion. Ein prädiktives Monitoring, z. B. durch Kardiotokographie (CTG) oder Ultraschall gibt es nicht. Eine medikamentöse Therapie mit Ursodeoxycholsäure (UDCA) bessert den Juckreiz, aber beeinflusst das fetale Outcome nicht nachweislich. Eine Entbindungsindikation ist in Abhängigkeit von Gallensäurenkonzentration und Gestationsalter gegeben. In Folgeschwangerschaften besteht ein hohes Wiederholungsrisiko.