Recent research efforts have increasingly concentrated on creating innovative biomaterials to improve bone tissue engineering techniques. Among these, hybrid nanomaterials stand out as a promising category of biomaterials. In this study, we present a straightforward, cost-efficient, and optimized hydrothermal synthesis method to produce high-purity Ta-doped potassium titanate nanofibers. Morphological characterizations revealed that Ta-doping maintained the native crystal structure of potassium titanate, highlighting its exciting potential in bone tissue engineering.

A Detailed geophysical investigation was conducted on Knossos territory of Crete Island. Main scope was the detection of underground archaeological settlements. Geophysical prospecting applied by an experienced geophysical team. According to area dimensions in relation to geological and structural conditions, the team designed specific geophysical techniques, by adopted non-catastrophic methods. Three different types of geophysical techniques performed gradually. Geophysical investigation consisted of the application of geoelectric mapping and geomagnetic prospecting. Electric mapping focusses on recording soil resistance distribution. Geomagnetic survey was performed by using two different types of magnetometers. Firstly, recorded distribution of geomagnetic intensity and secondly alteration of vertical gradient. Measured stations laid along the south-north axis with intervals equal to one meter. Both magnetometers were adjusted on a quiet magnetic station. Values were stored in files readable by geophysical interpretation software in XYZ format. Oasis Montaj was adopted for interpretation of measured physical properties distribution. Interpretation results were illustrated as color scale maps. Further processing applied on magnetic measurements. Results are confirmed by overlaying results from three different techniques. Geoelectric mapping contributed to detection of a few archaeological targets. Most of them were recorded by geomagnetic technique. Total intensity aimed to report the existence of magnetized bodies. Vertical gradient detected subsurface targets with clearly geometrical characteristics.

Introduction: It is universally accepted that the posteroanterior skull radiograph shows a lower degree of distortion than other radiographic images, so that measurements on it are considered reliable. Objective: To determine the percentage of distortion in the different facial regions of the postero-anterior skull radiograph. Methods: Thirty human skulls with their jaws were divided by three horizontal and four vertical planes into fifteen quadrants; there were ten in the skull and five in the jaw. On each of them a steel wire was placed in vertical and horizontal positions and their length (actual measurement) was measured. Each set was X-rayed in posteroanterior projection and the length of the wires was measured in the image (radiographic measurement). Results: It was not possible to measure in the lateral quadrants of the skull. The horizontal measurement in the right and left lower intermediate quadrants of the skull and in the intermediate and lateral quadrants of both sides of the mandible is not reliable; in the median quadrant of the mandible it is minimized; in the right and left upper intermediate and median quadrants of the skull and in the median of the mandible it is magnified. Vertical measurements in all quadrants are reliable; in the right and left upper intermediate and left upper and middle quadrants of the skull and in the right and left middle and lateral quadrants of the mandible it is magnified; in the lower intermediate and upper and lower middle quadrants of the skull and median of the mandible it is minimized. The least distortion for both measurements occurs in the upper median quadrant of the skull. Percentages of distortion are reported for each quadrant. Conclusions: Distortion is present in the posteroanterior skull radiograph and varies from one region of the face to another.

To address the problem that the imaging inversion method based on a single model in integrated aperture imaging is difficult to effectively correct model errors and perform accurate image reconstruction, a dual-model (DM)-based integrated aperture imaging inversion method is proposed for correcting the parametric errors of the inversion model and performing highly accurate millimeter-wave image reconstruction of the target scene. In view of the different parameter sensitivities of the Fourier transform (MFFT) model and the G-matrix (GM) model, the proposed DM method first corrects the imaging parameters with errors accurately by comparing the reconstruction errors of the two models; then recon-structs a high-precision target image based on the accurate GM model with the help of an improved regularization method. It is proved by simulation experiments that the proposed DM method can effectively correct the parameter errors of the imaging model and reconstruct the target scene with high accuracy in millimeter wave images compared with the traditional single-model imaging method.

Regarding to the influence of chloride and fluoride ions on the corrosion resistance, the electrochemical behavior of Ti alloys has been deeply studied. In this work, the main goal was to investigate the electrochemical behavior of cp-Ti and Ti-Mo alloys containing 6, 10 and 15 wt% of Mo concentrations. All the samples were immersed in different solutions, such as 0.15 mol L^-1 Na₂SO₄, 0.15 mol L^-1 Ringer, 0.15 mol L^-1 Ringer plus 0.036 mol L^-1 NaF and 0.036 mol L^-1 NaF. Simulating the commercial fluorinated gels, the NaF solutions naturally-aerated were prepared with 1450 ppm of fluoride ions. The electrochemical techniques applied in this work were the open-circuit potential, cyclic voltammetry, besides the technique for chemical identification, which was X-ray photoelectron spectroscopy. The formation and growth of TiO₂ and MoO₂ were identified, without pitting corrosion. The electrochemical stability and the corrosion resistance of the Ti-Mo alloys decreased in the solutions containing chloride and fluoride ions, with an appreciative decrease especially in the fluorinated medium. The Ti-Mo alloy with higher Mo content concentration was the material with higher corrosion resistance. Therefore, it is a promising candidate as a biomaterial, once the osseointegration needs a satisfactory corrosion resistance for being achieved.

This work is a part of research on the microstructure and mechanical properties of Cr-Ni-Si steels after various thermal treatments [1, 2]. The need to minimize damage and losses caused by emerging failures in complex engineering facilities such as nuclear, thermal and hydroelectric power stations, and gas and oil pipelines necessitates the creation of materials of high strength, plasticity, welding and high rigidity.