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The ability of juveniles of wide-ranging species to locate distant foraging regions can rely on innate or learned information. Reliance on innate cues could be problematic when conservation actions facilitate reintroduction. In the North Pacific, the short-tailed albatross Phoebastria albatrus is recovering from extensive harvesting, and has recently benefited from translocation efforts. Yet little is known about how naïve juveniles disperse or about individual distributions of immature short-tailed albatrosses. The primary goals of this study were to quantify the ontogeny of movement patterns and spatial distributions and compare these between naturally reared and translocated short-tailed albatrosses. We tracked 51 albatrosses for up to 5 years post-fledging: naturally reared chicks from their natal colony on Torishima, Japan, and chicks that were translocated 350 km to the southeast to Mukojima, Japan. Initial, more northerly dispersal of translocated fledglings suggests the ability to adjust to a new departure location. Fledglings’ departure paths differed from previously tracked adults departing Torishima, yet like adults, the majority of fledglings (81%) reached the Bering Sea that first summer, further supporting large-scale innate orientation abilities. Juveniles showed strong seasonal changes in distributions, traveling more in winter and occupying regions not typically used by adults (e.g. California Current, Sea of Okhotsk). As they aged, juveniles began to exhibit habitat fidelity to shelf-break regions, as anticipated from prior studies, yet continued to explore new regions with low levels of spatial fidelity. Juvenile short-tailed albatrosses explored almost the entire species range, highlighting the impressive capacity of individuals to transverse the North Pacific.

Background: This study evaluates the tracking accuracy of the lung tumor volume and fiducial markers using four-dimensional computed tomography (4DCT) and fitted neural network models. Materials and Methods: This study utilized data from 31 patients (109 fiducial markers) who underwent stereotactic body radiotherapy (SBRT). The respiratory movements of fiducial markers, lung tumors, and lung volume were calculated using 4DCT. Cross-correlation coefficients were then calculated to analyze the phase movements of fiducial markers, lung tumors, lung volume, direction displacement, and lung area (upper, middle, and lower lobes). Statistical prediction models were used to evaluate the predictive accuracy of the left--right (LR), anterior--posterior (AP), cranial--caudal (CC), and three-dimensional (3D) cross-correlation coefficients between fiducial markers and lung tumors. The coefficient of determination (R2) was used to determine the accuracy of the statistical prediction models for the explanatory variables. Results: The correlation between fiducial marker and lung tumor, as well as lung tumor movement by time phase, yielded the following R² values--LR: 0.920, AP: 0.319, CC: 0.675, and 3D: 0.449 for the upper lobe; LR: 0.567, AP: 0.627, CC: 0.955, and 3D: 0.939 for the middle/lower lobes. Statistically significant differences were observed in the CC and 3D directions within each lower lobe. Conclusions: The respiratory movements of fiducial markers and lung tumors in lung SBRT show stronger correlation with the movement of lung volume in the middle/ lower lobes compared to that in the upper lobes. Combining a fiducial marker with lung volume improves the prediction accuracy of the respiratory movement of lung tumors. [ABSTRACT FROM AUTHOR]

Research was conducted to examine the structural and vibrational features of device quality pure GaN substrate grown using a lateral epitaxial ovvergrowth method by x-ray diffraction, Brillouin, Raman and infrared spectroscopy. Lattice constants were observed to be close to bulk GaN and relaxed epilayers on sapphire. Results indicate extremely good structural quality of the GaN substrate with structural coherence length of as long as 1.9 micron along the c axis.