Considerations regarding carotid artery dose in radiotherapy of the cervical spine

Radiation to the carotid arteries, e.g. in the context of head and neck cancer treatment, is one of several risk factors for artery stenosis. In principle, this fact may also have implications for stereotactic cervical spine radiotherapy, because long-term survival can be achieved in patients with oligometastatic disease and favorable prognostic features. Here, we suggest that radiation dose distributions with reduced dose to the carotid artery are achievable when planning stereotactic cervical spine radiotherapy. Patients with high likelihood of long-term survival may benefit from such vessel-sparing approaches

A Temporal Approach to Defining Place Types based on User-Contributed Geosocial Content

Place is one of the foundational concepts on which the field of Geography has been built. Traditionally, GIScience research into place has been approached from a spatial perspective. While space is an integral feature of place, it represents only a single dimension (or a combination of three dimensions to be exact), in the complex, multidimensional concept that is place. Though existing research has shown that both spatial and thematic dimensions are valuable, time has historically been under-utilized in its ability to describe and define places and their types. The recent availability and access to user-generated geosocial content has allowed for a much deeper investigation of the temporal dimension of place. Multi-resolution temporal signatures are constructed based on these data permitting both place instances and place types to be compared through a robust set of (dis)similarity measures. The primary contribution of this work lies in demonstrating how places are defined through a better understanding of temporal user behavior. Furthermore, the results of this research present the argument that the temporal dimension is the most indicative placial dimension for classifying places by type

Calculation of reduced coefficients and matrix elements in jj-coupling

A program RCFP will be presented for calculating standard quantities in the decomposition of many-electron matrix elements in atomic structure theory. The list of quantities wich are supported by the present program includes the coefficients of fractional parentage, the reduced coefficients of fractional parentage, the reduced matrix elements of the unit operator T^{(k)} as well as the completely reduced matrix elements of the operator W^{(k_jk_q)} in jj-coupling. These quantities are now available for all subshells (nj) with j \leq 9/2 including partially filled 9/2-shells. Our program is based on a recently developed new approach on the spin-angular integration which combines second quantization and quasispin methods with the theory of angular momentum in order to obtain a more efficient evaluation of many-electron matrix elements. An underlying Fortran 90/95 module can directly be used also in (other) atomic structure codes to accelerate the computation for open-shell atoms and ions

Provenance and credibility in spatial and platial data

ISSN:1948-660