Single crystals of Y1−xRxCa4O(BO3)3 (R = Sc or Lu) of good quality have been grown from the melt by the Czochralski pulling method. The chemical compositions of the grown crystals were determined. Type-I noncritical phase matching (NCPM) wavelengths for second harmonic generation (SHG) in Y1−xRxCa4O(BO3)3 grown crystals were also determined.
The aim of present paper is to report the results on the modeling of the crystal field and spin-Hamiltonian parameters of Cr2+ doped in II-VI host matrix ZnS and simulate the energy levels scheme of such system taken into account the fine interactions entered in the Hamiltonian of the system. All considered types of such interaction are expected to give information on the new peculiarities of the absorption and emission bands, as well as of non-radiative transitions between the electronic states of impurity ions. The obtained results were disscused, compared with similar obtained results in literature and with experimental data.
Diana Vrîncianu, Cristina Ionită, Iulia Băra and Dorina Creangă
This study presents the effects induced by X-rays, medium doses (20-70 Gy), over the meristematic tissues of three cereal species: one of barley and two of wheat. The cytogenetic investigation was based on the response of young seedlings during their very early ontogenetic stages to the ionizing radiation exposure. The study was focused on the identification and counting of the chromosomal aberrations for various doses compared to the control samples. Qualitative evaluation revealed: interchromatidian bridges, expulsed chromosomes or chromosome fragments, and complex aberrations (combination of the already mentioned ones). The different behavior of these three species was discussed over the mitotic index, the number of abnormal ana-telophases and over the percentages of the mitosis phases. In each case, the mitotic index was increased in comparison with the control, and also the number of aberrations was found increased; however no evident mathematical correlations with applied doses could be established.
An arthritic knee affects the patient’s life by causing pain and limiting movement. If the cartilage and the bone surfaces are severely affected, the natural joint is replaced with an artificial joint. The procedure is called total knee arthroplasty (TKA). Lately, the numbers of implanted total knee prostheses grow steadily. An important factor in TKA is the perfect alignment of the total knee prosthesis (TKP) components. Component misalignment can lead to the prosthesis loss by producing wear particles. The paper proposes a study on mechanical behaviors of a TKP based on numerical analysis, using ANSYS software. The numerical analysis is based on both the normal and the changed angle of the components alignment.
Determining the center of pressure trajectories, as an indicator of postural stability or lumbar pathology, has been a challenging issue for researchers during the last decades. The paper advances an investigational method in order to determine a correlation between lumbar spine movements and feet center of pressure distribution. Five young healthy volunteers were simultaneously tested using an ultrasound based motion analyzing system and a force platform, while performing imposed tasks. Results showed specific patterns described by the center of pressure trajectories and a good coordination of angular amplitudes during lumbar spine movement.
Mihai Nicolae Dănilă, Florin Unga, Marius Mihai Cazacu, Adrian Timofte, Mitachi Strat, Dan Gheorghe Dimitriu and Silviu Gurlui
The eruption of both the Eyjafjallajokull (April 2010) and Grimsvotn (May 2011) volcanoes cumulated with two moments that gave headaches to the authorities and air traffic, and their impact on the environment upon Iasi region have been studied by means of different tools evidencing the complexity of the phenomena. In order to evidence the intrusion of pollutants in the cloud systems and to obtain additional data on the intrusion when the ash cloud was over our country, LIDAR measurements, meteorological (NMA), Satellite data (EUMETSAT), and various forecasting models (ECMWF, VAAC-Met Office, HYSPLIT) have been used. The new 3D Atmospheric Observatory Site of the Alexandru Ioan Cuza University of Iasi, as part of RADO (Romanian Atmospheric 3D Observatory) is presented, too.
A particular case of interactions of a single massless tensor field with the mixed symmetry corresponding to a two-column Young diagram (k,1) with k=4, dual to linearized gravity in D=7, is considered in the context of: self-couplings, cross-interactions with a Pauli-Fierz field, cross-couplings to purely matter theories, and interactions with an Abelian 1-form. The general approach relies on the deformation of the solution to the master equation from the antifield-BRST formalism by means of the local cohomology of the BRST differential.
Given the recent renewed interest in alternative description of gravity theories in terms of topological BF models (possibly with extra-constraints) as well as in dual formulations of linearized gravity (DFLG), all consistent interactions in D=6 involving an Abelian BF model with a maximal field spectrum and the DFLG via a massless tensor field with the mixed symmetry of the type (3,1) are considered.
The problem of quantization of the massive p-forms is considered in the framework of the Batalin-Fradkin (BF) approach based on path integral. The quantization procedure relies on the path integral of a first-class system equivalent with the original theory. This first-class system is constructed using the BF method.