Exploration of WEB resources in the domain of metal processing technologies

The amount of information contained in the WEB grows in a galloping way, which is caused by the spread of Internet access and lowering the cost of storing and sharing data across the network. The vast amount of data, impossible to be analyzed by human, is the reason why finding and selecting valuable information has become a serious problem. Due to this situation, a highly useful and desired solution would be the development of a system that would allow continuous monitoring of the WEB and finding for the user valuable information from the selected Internet resources. This paper describes the concept of such a system, along with its initial implementation and application to search for information in the field of foundry industry

Phase calibration of spatial light modulators by means of Fresnel images

Reliable application of spatial light modulators (SLMs) as programmable diffractive optical elements requires a thorough calibration. In this paper, we propose a method for calibrating SLMs based on the evaluation of Fresnel images. Fresnel images generated by a binary phase diffraction grating consist of binary irradiance distributions whose visibility depends on the phase modulation. By displaying on our device a diffraction grating with a binary phase step along one direction and a linearly increasing phase along the orthogonal direction, we perform a complete phase calibration. In this way, the phase modulation for every pixel and for every value of the entrance signal can be determined experimentally. Additionally, data acquisition can be significantly simplified with this schem

Effect of microstructure on properties of MgB 2 synthesized by SHS method

Abstract MgB 2 samples were obtained by self-propagating high-temperature synthesis (SHS). Microstructure, phase and chemical analysis of the samples were studied by XRD and cross-sectional TEM-SAD. MgB 2 samples contained very small uniformly distributed MgO particles. Temperature dependence of the upper critical field and of the critical current densities were determined from ac magnetic susceptibility measurements. Normal metallic state was characterised by measurements of valence band structure by ultraviolet photoelectron spectroscopy (ARUPS). We concluded that MgB 2 is a hard II type superconductor and that SHS method is suitable to fabricate material with strong pinning centers of MgO

OPTIMIZATION OF SIMULATION MODEL PARAMETERS FOR SOLIDIFICATION OF METALS WITH USE OF AGENT-BASED EVOLUTIONARY ALGORITHM

The finite elements method (FEM) is currently widely used for simulation of thermal processes.However, one of still unresolved problems remains proper selection of mathematicalmodel parameters for these processes. As far as modelling of cooling casts in forms is concerned,particular difficulties appear while estimating values of numerous coefficients suchas: heat transport coefficient between metal and form, specific heat, metal and form heatconduction coefficient, metal and form density. Coefficients mentioned above depend not onlyon materials properties but also on temperature. In the paper the idea of optimalizationof simulation method parameters based on adaptive adjustment of curve representing simulationresult and result obtained in physical experiment is presented along with the ideaof evolutionary and agent-based evolutionary optimization system designed to conduct suchoptimizations. Preliminary results obtained with use of ABAQUS system available in ACKCYFRONET and software developed at AGH-UST conclude the paper

Stem cells migration during skeletal muscle regeneration - the role of Sdf-1/Cxcr4 and Sdf-1/ Cxcr7 axis

The skeletal muscle regeneration occurs due to the presence of tissue specific stem cells - satellite cells. These cells, localized between sarcolemma and basal lamina, are bound to muscle fibers and remain quiescent until their activation upon muscle injury. Due to pathological conditions, such as extensive injury or dystrophy, skeletal muscle regeneration is diminished. Among the therapies aiming to ameliorate skeletal muscle diseases are transplantations of the stem cells. In our previous studies we showed that Sdf-1 (stromal derived factor ¡1) increased migration of stem cells and their fusion with myoblasts in vitro. Importantly, we identified that Sdf-1 caused an increase in the expression of tetraspanin CD9 - adhesion protein involved in myoblasts fusion. In the current study we aimed to uncover the details of molecular mechanism of Sdf-1 action. We focused at the Sdf-1 receptors - Cxcr4 and Cxcr7, as well as signaling pathways induced by these molecules in primary myoblasts, as well as various stem cells - mesenchymal stem cells and embryonic stem cells, i.e. the cells of different migration and myogenic potential. We showed that Sdf-1 altered actin organization via FAK (focal adhesion kinase), Cdc42 (cell division control protein 42), and Rac-1 (Ras- Related C3 Botulinum Toxin Substrate 1). Moreover, we showed that Sdf-1 modified the transcription profile of genes encoding factors engaged in cells adhesion and migration. As the result, cells such as primary myoblasts or embryonic stem cells, became characterized by more effective migration when transplanted into regenerating muscle

Raspberry pomace alters cecal microbial activity and reduces secondary bile acids in rats fed a high-fat diet

The profile of bile acids (BA) largely depends on the enzymatic activity of the microbiota, but this can be modulated by the dietary addition of biologically active compounds, e.g., polyphenols and polyunsaturated fatty acids. The aim of this study was to examine the effect of dietary raspberry pomace as a rich source of biologically active compounds on microbial activity and the BA profile in the caecum of rats fed a high-fat diet. Wistar rats were fed the standard diet AIN-93, a high-fat diet or a modified high-fat diet enriched with 7% different types of processed raspberry pomaces produced by standard grinding and fine grinding, with or without seeds. Rats fed the high-fat diet for eight weeks showed some disorders in liver function and cecal BA, as manifested by an increased concentration of cholesterol, total BA in the liver and cholic, deoxycholic, and β-muricholic acids in the cecal digesta. In general, irrespective of the type of raspberry pomace, these dietary preparations decreased liver cholesterol, hepatic fibroblast growth factor receptor 4, peroxisome proliferator-activated receptor alpha, cecal ammonia and favorable changed BA profile in the cecum. However, among all dietary pomaces, the finely ground preparation containing seeds had the greatest beneficial effect on the caecum by modulating bacterial activity and reducing the levels of secondary BA

The cranio-orbital foramen; a meta-analysis with a review of the literature

Background: The goal of the present study was to provide accurate data on the prevalence and morphometrical aspects of the cranio-orbital foramen (COF), which can surely be of use by surgeons performing procedures on the lateral orbit. Furthermore, the embryology and the clinical significance of this osseous structure were thoroughly discussed. Materials and methods: Major online medical databases such as PubMed, Scopus, Embase, Web of Science, and Google Scholar were searched to find all relevant studies regarding COF. Results: Eventually, a total of 25 studies that matched the required criteria and contained complete and relevant data were included in this meta-analysis. The pooled prevalence of COF was found to be 48.37% (95% CI: 41.67% - 55.10%). The occurrence of the COF unilaterally was set to be 71.92% (95% CI: 41.87% - 96.97%). The occurrence of the COF bilaterally was set at 26.08% (95% CI: 3.03% - 58.13%). Conclusions: In conclusion, we believe that this is the most accurate and up-to-date study regarding the anatomy of the COF. The COF is prevalent in 48.37% of the cases, and it is most frequently unilateral (73.92%). Furthermore, the prevalence of accessory COFs was found to be 16.72 percent. The presence of these foramina may represent a source of hemorrhage that ophthalmic surgeons should be aware of when performing procedures in the lateral part of the orbit