Structurally complex Frank-Kasper phases and quasicrystal approximants: electronic origin of stability

Metal crystals with tetrahedral packing are known as Frank-Kasper phases with large unit cells with the number of atoms from hundreds to thousands. The main factors of the formation and stability of these phases are the atomic size ratio and the number of valence electrons per atom. The significance of the electronic energy contribution is analyzed within the Fermi sphere - Brillouin zone interactions model for several typical examples: Cu4Cd3, Mg2Al3 with over thousand atoms per cell, and for icosahedral quasicrystal approximants with 146 to 168 atoms per cell. Our analysis shows that to minimize the crystal energy, it is important that the Fermi sphere (FS) is in contact with the Brillouin zones that are related to the strong diffraction peaks: the zones either inscribe the FS or are circumscribed by the FS creating contact at edges or vertices.Comment: 10 pages, 3 figures, 1 tabl

Evaluation of time-series registration methods in dynamic area telethermometry for breast cancer detection

Automated motion reduction in 3D dynamic infrared imaging is on demand in many applications. Few methods for registering time-series dynamic infrared frames have been proposed. Almost all such methods are feature based algorithms requiring manual intervention. We apply different automated registration methods based on spatial displacement to 11 datasets of Breast Dynamic Infrared Imaging (DIRI) and evaluate the results in terms of both the image similarity and anatomical consistency of the transformation. The aim is to optimize the registration strategy for breast DIRI in order to improve the spectral analysis of temperature modulation; thus facilitating the acquisition procedure in a Dynamic Area Telethermometry framework. The results show that symmetric diffeomorphic demons registration outperforms both warped frames similarity and smoothness of deformation fields; hence proving effective for time-series dynamic infrared registratio

A spectral deferred correction strategy for low Mach number reacting flows subject to electric fields

We propose an algorithm for low Mach number reacting flows subjected to electric field that includes the chemical production and transport of charged species. This work is an extension of a multi-implicit spectral deferred correction (MISDC) algorithm designed to advance the conservation equations in time at scales associated with advective transport. The fast and nontrivial interactions of electrons with the electric field are treated implicitly using a Jacobian-Free Newton Krylov approach for which a preconditioning strategy is developed. Within the MISDC framework, this enables a close and stable coupling of diffusion, reactions and dielectric relaxation terms with advective transport and is shown to exhibit second-order convergence in space and time. The algorithm is then applied to a series of steady and unsteady problems to demonstrate its capability and stability. Although developed in a one-dimensional case, the algorithmic ingredients are carefully designed to be amenable to multidimensional applications

Parametrised modified gravity and the CMB Bispectrum

We forecast the constraints on modified theories of gravity from the cosmic microwave background (CMB) anisotropies bispectrum that arises from correlations between lensing and the Integrated Sachs-Wolfe effect. In models of modified gravity the evolution of the metric potentials is generally altered and the contribution to the CMB bispectrum signal can differ significantly from the one expected in the standard cosmological model.We adopt a parametrised approach and focus on three different classes of models: Linder's growth index, Chameleon-type models and f(R) theories. We show that the constraints on the parameters of the models will significantly improve with future CMB bispectrum measurements.Comment: 7 pages, 6 figure

Faktor Penyebab Kerusakan Dokumen Rekam Medis di Ruang Penyimpanan RSU Mitra Sejati Medan

Dokumen rekam medis merupakan alat untuk merekam mencatat terjadinya transaksi pelayanan sehingga harus dijaga keamanan dan kerahasiaannya dari bahaya kerusakan. Tujuan penelitian ini untuk mengetahui faktor penyebab kerusakan dokumen rekam medis di ruang penyimpanan RSU Mitra Sejati Medan. Penelitian ini bersifat deskriptif. Populasi adalah seluruh dokumen rekam medis yang ada di ruang Penyimpanan RSU Mitra Sejati Medan dan sampelnya diambil secara simple random sampling yang berjumlah 96 berkas. Data diperoleh dari hasil observasi menggunakan kuesioner dan pengukuran. Analisis data dilakukan secara univariat. Dari hasil penelitian diperoleh kerusakan dokumen rekam medis di ruang penyimpanan RSU Mitra Sejati Medan sebesar 41,6%. Faktor intrinsik yang meliputi kualitas kertas, tinta dan perekat bukan penyebab kerusakan pada dokumen rekam medis. Faktor ekstrinsik yaitu atap yang bocor, ada rembesan air di dinding, kabel listrik tidak tersusun rapi, sinar matahari langsung jatuh di permukaan dokumen, kelembaban udara, suhu, jamur dan debu dapat menjadi penyebab kerusakan pada dokumen rekam medis di ruang penyimpanan RSU Mitra Sejati Medan. Disarankan kepada pihak RSU Mitra Sejati agar dapat menambah fasilitas di ruang penyimpanan seperti penggunaan tirai, blower, AC dan memperbaiki atap dan rembesan air di dinding