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    Adult Intracranial Ependymal Tumors: Results of TROD Neurooncology Group 07-009 Study
    (Elsevier Ireland Ltd, 2022) Arslan, S. Aytac; Guney, Y.; Erpolat, P.; Kamer, S.; Ercis, E.; Tezcan, Y.; Akgun, Z.
    [No Abstract Available]
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    Comparison of hematologic toxicity between 3DCRT and IMRT planning in cervical cancer patients after concurrent chemoradiotherapy: a national multi-center study
    (I R O G Canada, Inc, 2014) Erpolat, O. P.; Alco, G.; Caglar, H. B.; Igdem, S.; Saran, A.; Dagoglu, N.; Aslay, I.; Ozsaran, Z.; Demirci, S.; Keven, E.; Guney, Y.; Akmansu, M.; Kilic, D.; Bayman, E.; Etiz, D.; Mandel, N. M.
    Purpose: To compare the incidence and severity of acute and chronic hematologic toxicity (HT) in patients treated with three-dimensional conformal radiotherapy (3DCRT) and intensity modulated radiotherapy (IMRT) for curative treatment of cervical cancer and to ascertain the dosimetric parameters of two techniques associated with acute and chronic HT. Materials and Methods: A total of 127 patients with cervical cancer receiving concomitant pelvic radiotherapy (RT) and cisplatin were evaluated. Pelvic bone marrow (BM) was contoured for each patient and divided into five sub-regions: lumbosacrum (LS), ilium (IL), lower pelvis (LP), pelvis (P), and whole pelvis (WP). The volume of each BM region receiving 10,20,30, and 40 Gy was calculated (V10, -V20, -V30, and -V40). The lowest level of hemoglobin, leukocyte, neutrophil, and platelet counts were obtained during chemoradiotherapy and six months after RT. The nadir values were graded according to Common Terminology Criteria for Adverse Events (version 3.0). Results: Grade 2 or greater acute anemia, leukopenia, neutropenia, thrombocytopenia was observed in 2%, 41.5%, 12%,and 0% in 3DCRT group and in 27%, 53%, 24.5%, and 4.5% in IMRT group, respectively. Grade 2 or greater chronic anemia, leukopenia, neutropenia, and thrombocytopenia was observed in 11%, 10%, 6%, and 0% in 3DCRT group and in 11%, 9%, 4.5%, and 0% in IMRT group, respectively. LS-V30,40; IL-V10,20,30,40; LP-V10,20,40; P-V10,20,30,40, and TP-V10,20,30,40 were significantly reduced with IMRT planning compared to 3DCRT planning. Logistic regression analysis of potential predictors showed that none of the dosimetric parameters were significant for predicting acute and chronic HT. Conclusion: The present findings showed that IMRT planning reduced irradiated BM volumes compared to 3DCRT planning. However, no difference between the two techniques was observed in terms of acute and chronic HT. Further studies are needed to confirm these results.
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    The Role of Radiotherapy in Intracranial Hemangiopericytoma: TROD CNS Group Study 07-008
    (Elsevier Ireland Ltd, 2022) Kaydihan, N.; Guney, Y.; Yazici, G.; Erpolat, P.; Kamer, S.; Atasoy, B. M.; Aslan, D.
    [No Abstract Available]
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    The size, shape, density and ring of the dwarf planet Haumea from a stellar occultation
    (Nature Publishing Group, 2017) Ortiz, J. L.; Santos-Sanz, P.; Sicardy, B.; Benedetti-Rossi, G.; Berard, D.; Morales, N.; Duffard, R.; Braga-Ribas, F.; Hopp, U.; Ries, C.; Nascimbeni, V.; Marzari, F.; Granata, V.; Pal, A.; Kiss, C.; Pribulla, T.; Komzik, R.; Hornoch, K.; Pravec, P.; Bacci, P.; Maestripieri, M.; Nerli, L.; Mazzei, L.; Bachini, M.; Martinelli, F.; Succi, G.; Ciabattari, F.; Mikuz, H.; Carbognani, A.; Gaehrken, B.; Mottola, S.; Hellmich, S.; Rommel, F. L.; Fernandez-Valenzuela, E.; Campo Bagatin, A.; Cikota, S.; Cikota, A.; Lecacheux, J.; Vieira-Martins, R.; Camargo, J. I. B.; Assafin, M.; Colas, F.; Behrend, R.; Desmars, J.; Meza, E.; Alvarez-Candal, A.; Beisker, W.; Gomes-Junior, A. R. .; Morgado, B. E. .; Roques, F.; Vachier, F.; Berthier, J.; Mueller, T. G.; Madiedo, J. M.; Unsalan, O.; Sonbas, E.; Karaman, N.; Erece, O.; Koseoglu, D. T. .; Ozisik, T.; Kalkan, S.; Guney, Y.; Niaei, S.; Satir, O.; Yesilyaprak, C.; Puskullu, C.; Kabas, A.; Demircan, O.; Alikakos, J.; Charmandaris, V.; Leto, G.; Ohlert, J.; Christille, J. M.; Szakats, R.; Farkas, A. Takacsne; Varga-Verebelyi, E.; Marton, G.; Marciniak, A.; Bartczak, P.; Santana-Ros, T.; Utkiewicz-Bak, M. B.; Dudzinski, G.; Ali-Lagoa, V.; Gazeas, K.; Zouganatos, L. T.; Paschalis, N.; Tsamis, V.; Sanchez-Lavega, A.; Perez-Hoyos, S.; Hueso, R.; Guirado, J. C. .; Peris, V.; Iglesias-Marzoa, R.
    Haumea-one of the four known trans-Neptunian dwarf planets is a very elongated and rapidly rotating body(1-3). In contrast to other dwarf planets(4-6), its size, shape, albedo and density are not well constrained. The Centaur Chariklo was the first body other than a giant planet known to have a ring system(7), and the Centaur Chiron was later found to possess something similar to Chariklo's rings(8,9). Here we report observations from multiple Earth-based observatories of Haumea passing in front of a distant star (a multi chord stellar occultation). Secondary events observed around the main body of Haumea are consistent with the presence of a ring with an opacity of 0.5, width of 70 kilometres and radius of about 2,287 kilometres. The ring is coplanar with both Haumea's equator and the orbit of its satellite Hi'iaka. The radius of the ring places it close to the 3:1 mean-motion resonance with Haumea's spin period-that is, Haumea rotates three times on its axis in the time that a ring particle completes one revolution. The occultation by the main body provides an instantaneous elliptical projected shape with axes of about 1,704 kilometres and 1,138 kilometres. Combined with rotational light curves, the occultation constrains the three-dimensional orientation of Haumea and its triaxial shape, which is inconsistent with a homogeneous body in hydrostatic equilibrium. Haumea's largest axis is at least 2,322 kilometres, larger than previously thought, implying an upper limit for its density of 1,885 kilograms per cubic metre and a geometric albedo of 0.51, both smaller than previous estimates(1,10,11). In addition, this estimate of the density of Haumea is closer to that of Pluto than are previous estimates, in line with expectations. No global nitrogen- or methane-dominated atmosphere was detected.