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[en] In this work, we present negative-ion fractions as a function of exit velocity and angle after keV-energy negative oxygen and carbon ions scattering on a highly oriented pyrolytic graphite (HOPG) surface, at a scattering angle of 38°. The negative-ion fractions increase monotonously with the increase of exit velocity for specular scattering, while negative-ion fractions present a bell-shaped dependence on exit angle. In order to gain further insight into the nature of charge transfer on HOPG, a modified charge transfer model involving the contribution of positive ions has been proposed and roughly reproduced the velocity and angle dependences of negative-ion fractions.
[en] Objectives: Although mitochondria are known to play an important role in radiation-induced cellular damage response, the mechanisms of how radiation elicits mitochondrial responses are largely unknown.
[en] A Michelson Spectrophotometer system was used to obtain two spectra of Zeta Orionis covering the entire wavelength range from 4000 A to beyond 10,000 A. These spectra are of photometric precision and have been corrected for all significant atmospheric absorptions. The C III multiplet was identified and measured at 9701-17 A, which has not previously been measureable because of atmospheric water-vapor absorptions in this region. The 60-Angstrom-wide band around the C III feature at 5696 A is not confirmed
[en] Purpose: To summarize the results of treatment for sacral chordoma in Phase I-II and Phase II carbon ion radiotherapy trials for bone and soft-tissue sarcomas. Patients and Methods: We performed a retrospective analysis of 38 patients with medically unresectable sacral chordomas treated with the Heavy Ion Medical Accelerator in Chiba, Japan between 1996 and 2003. Of the 38 patients, 30 had not received previous treatment and 8 had locally recurrent tumor after previous resection. The applied carbon ion dose was 52.8-73.6 Gray equivalents (median, 70.4) in a total of 16 fixed fractions within 4 weeks. Results: The median patient age was 66 years. The cranial tumor extension was S2 or greater in 31 patients. The median clinical target volume was 523 cm3. The median follow-up period was 80 months. The 5-year overall survival rate was 86%, and the 5-year local control rate was 89%. After treatment, 27 of 30 patients with primary tumor remained ambulatory with or without supportive devices. Two patients experienced severe skin or soft-tissue complications requiring skin grafts. Conclusion: Carbon ion radiotherapy appears effective and safe in the treatment of patients with sacral chordoma and offers a promising alternative to surgery.
[en] At the Congress of the Societe Francaise de Radiotherapie Oncologique (S.F.R.O.) from 2007, will be presented as a poster the legal structure and the organisational structure of the governance of the project, regulatory steps and technical achievements of the project, the state of progress in November 2007, the organisation's recruitment and timing of realisation of the centre which is expected to open in late 2012. (N.C.)
[en] Highlights: • The different distribution patterns of multiply charged ions on polarization state is presented. • A theoretical calculation could explain the related experimental results. • The cluster disintegration should be considered for the production of multiply charged ions. This paper investigated the dependence of multiply charged ions on the laser polarization state when benzene cluster was irradiated with 532 and 1064 nm nanosecond laser. A circle, square and flower distribution for C2+, C3+ and C4+ were observed with 532 nm laser respectively, while flower petals for C2+, C3+ and C4+ were observed at 1064 nm as the laser polarization varied. A theoretical calculation was performed to interpret the polarization state and wavelength dependence of the multiply charged ions. The simulated results agreed well with the experimental observation with considering the contribution from the cluster disintegration.
[en] Using 121.4 fb−1 of data collected with the Belle detector at the ϒ(5S) resonance at the KEKB asymmetric-energy e+e− collider, we report evidence for the B¯s0→Λc+Λ¯π− decay mode with a measured branching fraction (3.6±1.1[stat.]−0.5+0.3[syst.]±0.9[Λc+]±0.7[NB¯s0])×10−4 and a significance of 4.4 standard deviations. This is the first evidence for a baryonic Bs0 decay
[en] Negative carbon ions formation rate during bombarding of cometary ice surface by charged solar particles (hydrogen protons) is calculated in this work. Experimentally obtained Na+, K+, Rb+, Cs+ and Ar+ negative ions emission coefficients are used to accomplish this task. (author)
[en] Purpose: To evaluate the applicability of carbon ion radiotherapy (CIRT) for unresectable retroperitoneal sarcomas with regard to normal tissue morbidity and local tumor control. Methods and Materials: From May 1997 to February 2006, 24 patients (17 male and 7 female) with unresectable retroperitoneal sarcoma received CIRT. Age ranged from 16 to 77 years (median, 48.6 years). Of the patients, 16 had primary disease and 8 recurrent disease. Histologic diagnoses were as follows: malignant fibrous histiocytoma in 6, liposarcoma in 3, malignant peripheral nerve sheath tumor in 3, Ewing/primitive neuroectodermal tumor (PNET) in 2, and miscellaneous in 10 patients. The histologic grades were as follows: Grade 3 in 15, Grade 2-3 in 2, Grade 2 in 3, and unknown in 4. Clinical target volumes ranged between 57 cm3 and 1,194 cm3 (median 525 cm3). The delivered carbon ion dose ranged from 52.8 to 73.6 GyE in 16 fixed fractions over 4 weeks. Results: The median follow-up was 36 months (range, 6-143 months). The overall survival rates at 2 and 5 years were 75% and 50%, respectively. The local control rates at 2 and 5 years were 77% and 69%. No complications of the gastrointestinal tract were encountered. No other toxicity greater than Grade 2 was observed. Conclusions: Use of CIRT is suggested to be effective and safe for retroperitoneal sarcomas. The results obtained with CIRT were a good overall survival rate and local control, notwithstanding the fact that most patients were not eligible for surgical resection and had high-grade sarcomas.