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The purpose of the present retrospective study was to evaluate whether dosimetric differences existed in nodal clinical target volume (CTV) using options for geometric expansion and lymph node (LN) stations based on the European Society for Radiotherapy and Oncology guideline for locally advanced non-small cell lung cancer (NSCLC). In the treatment planning computed tomographic images of 17 patients with cT4N2M0 NSCLC, nodal CTVs were contoured based on the guideline options of: i) Geometric expansion, with CTV including the nodal gross tumor volume plus 5 mm margin; and ii) LN stations, with CTV including the affected LN stations. Treatment planning of 60 Gy in 30 fractions was performed using volumetric modulated arc therapy; Dmean was the mean irradiated dose to the structure; and VnGy was the volume of the structure receiving ≥n Gy. Dose-volume parameters were compared between the two options. Consequently, the option of geometric expansion was associated with a significantly lower V60Gy and Dmean of the esophagus, V20Gy, V5Gy and Dmean of the lungs, and Dmean of the heart than the option of LN stations in all patients (P=0.017, P<0.001, P<0.001, P<0.001, P<0.001 and P=0.029, respectively). For the V20Gy of the lungs, the 8 patients (47%) with LN metastases in stations 2 or 3 had significantly larger differences in the values between the two options than the 9 patients (53%) without those metastases; the median values of the difference of V20Gy of the lungs between the two options were 2.8% (range, 0.2 to 9.6%) with LN metastases in stations 2 or 3 and 0.5% (range, -0.2 to 5.0%) without these metastases (P=0.027). In conclusion, using the option for geometric expansion might help reduce the V60Gy and Dmean of the esophagus, V20Gy, V5Gy and Dmean of the lungs, and Dmean of the heart in all patients, and the V20Gy of the lungs in patients with LN metastases in stations 2 or 3. [ABSTRACT FROM AUTHOR]

Several pottery sherds from the Svilengrad-Brantiite site, Bulgaria, were mineralogically and petrographically analyzed. The aim was to add information to the very scarce material data available for Early Bronze Age pottery in the southeastern Thrace plain, Bulgaria, in order to examine a possible raw-material source of the pottery. The characterization techniques applied were optical microscopy (OM), petrographic microscopy (PM), scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM-EDS), X-ray fluorescence (XRF) spectroscopy, and X-ray diffraction (XRD). The pottery samples consisted of two typological groups: a local-made type and a cord-impressed decoration type influenced by foreign cultures. All of the samples were produced from fine clay pastes that had a quite similar composition, with abundant mineral grains of similar mineral composition and fragments of metamorphic and granitic rocks. The chemical compositions of each mineral in the grains and fragments were almost identical, and consistent with those from metamorphic and granitic rocks from the Sakar-Strandja Mountains near the study site. The clay paste compositions corresponded to those of illite/smectite mixed-layer clay minerals or mixtures of illite and smectite, and the clay-mineral species were consistent with those in Miocene–Pleistocene or Holocene sediments surrounding the site. [ABSTRACT FROM AUTHOR]