We have investigated the vibrational density of states (VDOS) of a thin Cu nanowire with <100> axial orientation and considered the effect of axial strain. The VDOS are calculated using a real space Green's function approach with the force constant matrices extracted from interaction potential based on the embedded atom method. Results for the vibrational density of states of a strain-free nanowire show quite distinctive characteristics compared to that of a bulk atom, the most striking feature of which is the existence of high frequency modes above the top of the bulk spectrum. We further predict that the low frequency characteristics of the VDOS reveal the quasi-1 dimensional (Q1D) behavior only when the wire is extremely thin.Through decomposition of VDOS into local atoms we also exhibit that while the anomalous increase in low frequency density of states is mainly due to the corner atoms, the enhancement in high frequency modes is primarily moderated by core atoms. We, additionally, find that while the high frequency band above the top of the bulk phonon shifts to higher frequencies, the characteristics at low frequencies remains almost the same upon stretching the nanowire along the axial direction.

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We construct a minimal content-based realization of the duplication and divergence model of genomic networks introduced by Wagner [A. Wagner, Proc. Natl. Acad. Sci. 91, 4387 (1994)] and investigate the scaling properties of the directed degree distribution and clustering coefficient. We find that the content based network exhibits crossover between two scaling regimes, with logperiodic oscillations for large degrees. These features are not present in the original gene duplication model, but inherent in the content based model of Balcan and Erzan. The scaling exponents γ1 and γ2 = γ1 − 1/2 of the Balcan-Erzan model turn out to be robust under duplication and point mutations, but get modified in the presence of splitting and merging of strings. The clustering coefficient as a function of the degree, C(d), is found, for the Balcan-Erzan model, to behave in a way qualitatively similar to the out-degree distribution, however with a very small exponent α1 = 1 − γ1 and an envelope for the oscillatory part, which is essentially flat, thus α2 = 0. Under duplication and mutations including splitting and merging of strings, C(d) is found to decay exponentially.

The behaviour of a hydrophobic chain near a hydrophobic wall is studied in three dimensions by numerically simulating a modified version of the decorated lattice model of Widom and co-workers. The effective hydrophobic interaction is temperature dependent. The chain stretches and adheres to the hydrophobic wall in a pancake like conformation at intermediate temperatures, whereas it collapses upon itself at slightly higher temperatures. At lower or higher dimensions it is in a random coil state.

Aims: The current study aimed to evaluate the efficacy, side effects of radiotherapy and factors influencing treatment outcome in patients received radiotherapy for cerebral meningiomas. Methods and Material: In the last two decades, a total of 35 patients with cerebral meningioma who received radiotherapy in our clinic were evaluated statistically in terms of survival, toxicity and prognostic factors. The records of patients diagnosed with cerebral meningioma who underwent postoperative radiotherapy were retrospectively analyzed. Statistical analysis used: Statistical comparisons were made using IBM SPSS v24.0. Kaplan-Meier method was used to compare survival times. Results: Five of the patients had grade I meningioma showing recurrence, 18 were grade II meningioma and 12 were grade III meningioma. Patients were treated with 54 or 60 Gy adjuvant radiotherapy with 2 Gy daily fractions according to histopathological grade and operation type. Three and five-year overall survival rates were 56% and 40%, respectively and median overall survival was 36 months. Progression was observed in 15 of the 35 patients included in the study. Three and five-year progression-free survival (PFS) rates of the patients were 56% and 50%, respectively. There was a statistically significant correlation between histopathological grade and overall survival among patients. However; no statistical difference found in overall survival of patients in terms of tumor location, operation type and age. Conclusions: In the treatment of cerebral meningiomas, changes in radiotherapy dose and field designs can be predicted according to the tumor grade and operation type. In addition, it is thought that large scale studies are needed to determine prognostic factors more meticulously.