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3-D conformal HDR brachytherapy as monotherapy using intraoperative real-time planning is a feasible and highly conformal treatment for localized prostate cancer associated with minimal acute toxicity. Longer follow-up is needed to evaluate late toxicity and biochemical control.

Simultaneous observations of energetic ions (•> 50 keV) and electrons (•> 220 keV) by the IMP 7 and 8 spacecraft, carrying identical instruments and located within the distant (-37 RE) magnetotail and upstream from the bow shock, have been employed to separate temporal variations from spatial variations during the upstream ion events observed on December 3, 1977 and November 2-3, 1977, in order to determine the source of these particles. The IMP data, when compared with those from ISEE 1 and 2, have also made possible the determination of field-aligned and flux-tube intensity gradients in the upstream region, thus enabling the test of specific predictions of the Fermi acceleration model for such events. The analysis of these three-spacecraft observations and comparison with theory have revealed the following' (1) For each of the observed upstream enhancements, energetic ions and electrons were simultaneously present inside the plasma sheet--successive increases were in excellent time coincidence with substorm injection events seen on ground-based magnetograms' (2) The low-energy (_> 50 keV) ion intensity profile inside the plasma sheet was relatively flat, while at higher (_> 300 keV) energies there was considerable variability, with one case exhibiting an "inverse velocity dispersion" profile; (3) Relativistic electron bursts were seen inside the plasma sheet and also upstream of the shock but at substantially reduced intensities' (4) The ion energy spectrum for the December 3 event, extended to energies ---2 MeV, was identical in form within the plasma sheet and upstream of the shock and can be described well by dj/dE oc E-5-5;(5) Ion anisotropies exhibited typically large dawn-dusk or dusk-dawn gradients, depending on spacecraft location, and showed large (up to 20:1) field-aligned streaming away from the bow shock; (6) Comparison of IMP and ISEE 2 intensities at ---60 keV for identical magnetic connections to the bow shock during a period when the interplanetary magnetic field (IMF) was radial showed the IMP 7 intensity to be higher by a factor ---10, even though IMP 7 was ---20 R E further from the bow shock, but located toward the dusk side of the earth-sun line' and (7) Comparison of unidirectional intensities of IMP 8 and ISEE 1 along the same radial IMF line showed the field-aligned component to be identical at both spacecraft, while the omnidirectional intensities give a gradient of ---2.5ø70/RE . The observations are compared with predictions of the Fermi model, and it is found that they are inconsistent with the principal features of the model, including the energy extent, form of the spectrum, anisotropies, scale lengths of acceleration region, IMF connection times, and the presence of electrons. 12,083 12,084 SARRIS ET AL.' UPSTREAM IONS OF MAGNETOSPHERIC ORIGIN

Simultaneous observations of energetic ions (≳50 keV) and electrons (≳220 keV) by the IMP‐7 and IMP‐8 spacecraft carrying identical instruments and located within the distant (∼37 Re) magnetotail and upstream of the bow shock, respectively, are reported during the period 0000–1100 UT on October 31, 1977. During this period, ISEE‐1 detectors had detected an upstream ion event [Ipavich et al., 1979]. The IMP observations, including measurements of the interplanetary magnetic field (IMF), reveal the following: (1) energetic ions and electrons were present inside the plasma sheet ≳ 1 hour prior to onset of the event upstream at IMP‐8. (2) Ion (50 ≤ E ≲ 200 keV) intensities inside the plasma sheet were always higher than those upstream by factors of ∼2 to ∼8. (3) The ion energy spectrum upstream of the shock can be fit well by a power law, dj/dE ∝ E−4.1, from ∼50 keV to ∼2 MeV; observations at higher energies were precluded by high fluxes of ambient solar energetic particles. (4) Dawn‐dusk anisotropies of upstream ions as large as 5∶1 are interpreted as due to density gradients; anisotropies in the plasma sheet were, at times, both earthward and tailward. (5) The presence of ions upstream was controlled by the direction of the IMF: connection to the bow shock was necessary, but not sufficient, for the appearance of ions. These observations show that ions observed upstream of the shock on October 31, 1978, most likely originated from within the earth's plasma sheet; a phenomenological model is suggested for such particle “leakage.” The observations are inconsistent with most major predictions of the Fermi acceleration model for such events, including the energy extent, the shape of the ion spectrum, the particle anisotropies, and the IMF connection time.

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For patients with recurrences of GBM within previously irradiated volumes, CT-guided interstitial HDR-BRT is a feasible treatment option that can play an important role in providing palliation.

The AMPTE/CCE spacecraft, with an apogee of ∼8.8RE and an inclination of ∼4.3°, sampled the outer dayside equatorial magnetosphere for extended time periods and often crossed into the magnetosheath whenever the solar wind pressure was sufficiently high to compress the magnetopause to <8.8RE. We have analyzed ion distributions on both sides of the magnetopause in order to investigate any local time and energy dependence, giving information about physical processes at the magnetopause and the bow shock. Particle measurements are from the CHEM (1.5 to 300 keV/e) and MEPA (10 keV to 2 MeV) instruments. The wide total energy range (1.5 keV to 2 MeV) covered describes the magnetospheric distributions quite well, and for the purpose of this study, adequately describes the high‐energy part of the shocked solar wind. Thus both solar wind and magnetospheric components can be recognized in a mixed particle distribution. Case studies of representative magnetopause crossings at dawn, noon, and dusk, as well as a survey of several other crossings, indicated: (1) a local time and energy dependence of magnetosheath spectra at energies ≥50 keV; spectra were harder at the duskside than at the dawnside and also correlated with magnetospheric activity, (2) constantly much higher intensities in the magnetosphere than in the magnetosheath at energies >10 keV and an earthward gradient in the subsolar magnetosheath. In addition to the steady state magnetosheath population there exists a burst‐type component indicative of a magnetospheric source, and most of the time this is recognized as a flux transfer event. Overall, the results about the origin of the ≥50 keV magnetosheath ions are consistent with the continuous leakage of magnetospheric particles across a tangential discontinuity magnetopause, locally distributed according to magnetospheric drift paths. Magnetic reconnection, although present, should not be a dominant source on average, because it is not continuous in time. Fermi acceleration should not be dominant because it predicts the opposite local time asymmetry, and shock drift acceleration should be a minor contributor at E≥50 keV because of upper‐energy cutoff limitations. Our observations also indicate a significant magnetospheric contribution to energies as low as ∼10 keV, where the magnetosphere‐magnetosheath intensity gradient reverses. However, in order to examine the relative strength and local time distribution of all possible sources at these energies, a detailed analysis is required.

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