Supporting QoS in Integrated Ad-Hoc Networks

Ad-hoc networking is becoming a promising solution to increase the radio coverage of wireless systems. Integrated mobile ad-hoc networks (MANETs), considered as multi-hop networks connected to fixed networks through one or more gateways, seem to be very profitable for both the provider and the user. This article describes an architecture for end-to-end QoS in such MANETs, developed within the IST project DAIDALOS II. In order to explain the framework’s functionality, the technology, service differentiation mechanisms, MAC layer measurements, and signalling protocols are discussed. The modules required by the network elements as well as their integration are also described. Additionally, the paper presents the results obtained during verification tests performed in exemplary testbed scenarios.     

Effects of extreme pressure and anti-wear additives on surface topography and tool wear during MQCL turning of AISI 1045 steel

The paper presents an original study of the influence of extreme pressure and anti-wear (EP/AW) additives on the surface topography of double-phase steel during turning with different cooling media and variable flow rates. The obtained surface topographies were compared using frequency and fractal analyses for dry, minimum quantity cooling lubrication (MQCL), and MQCL + EP/AW methods. Results showed that the addition of phosphate ester-based additives to an active medium caused the formation of tribofilm on the tool-chip interface and thus a change in the lubricating properties by reducing friction. The tool wear and the formation of the thin-layered tribofilm were also incorporated. The application of the MQCL method with the EP/AW additives led to a decrease in particular surface topography parameters from 8 % to 38 % in comparison with the effects of dry cutting and from 6 % to 35 % in comparison with the effects of machining under MQCL conditions. An exception was the result obtained for the surface roughness height parameter Sp, which was higher than that obtained after the MQCL + EP/AW process for the lowest investigated feed per revolution f = 0.1 mm/rev. This observation was correlated with the uneven formation of the tribofilm on the machined surface. The phosphate ester-based additive used in the MQCL + EP/AW method contributed to achieving tool wear that was less than that obtained by the processes conducted under dry and MQCL conditions.     

Molecular Imaging of Human Skeletal Myoblasts (huSKM) in Mouse Post-Infarction Myocardium

Current treatment protocols for myocardial infarction improve the outcome of disease to some extent but do not provide the clue for full regeneration of the heart tissues. An increasing body of evidence has shown that transplantation of cells may lead to some organ recovery. However, the optimal stem cell population has not been yet identified. We would like to propose a novel pro-regenerative treatment for post-infarction heart based on the combination of human skeletal myoblasts (huSkM) and mesenchymal stem cells (MSCs). huSkM native or overexpressing gene coding for Cx43 (huSKMCx43) alone or combined with MSCs were delivered in four cellular therapeutic variants into the healthy and post-infarction heart of mice while using molecular reporter probes. Single-Photon Emission Computed Tomography/Computed Tomography (SPECT/CT) performed right after cell delivery and 24 h later revealed a trend towards an increase in the isotopic uptake in the post-infarction group of animals treated by a combination of huSkMCx43 with MSC. Bioluminescent imaging (BLI) showed the highest increase in firefly luciferase (fluc) signal intensity in post-infarction heart treated with combination of huSkM and MSCs vs. huSkM alone (p < 0.0001). In healthy myocardium, however, nanoluciferase signal (nanoluc) intensity varied markedly between animals treated with stem cell populations either alone or in combinations with the tendency to be simply decreased. Therefore, our observations seem to show that MSCs supported viability, engraftment, and even proliferation of huSkM in the post-infarction heart.     

Functionalized tricalcium phosphate and poly(3-hydroxyoctanoate) derived composite scaffolds as platforms for the controlled release of diclofenac

Novel bone substitutes such as highly porous ceramic scaffolds can serve as platforms for delivering active molecules. A common problem is to control the release of the drug, therefore, it is beneficial to use a drug-functionalized polymer coating. In this study, β-tricalcium phosphate-based porous scaffolds were obtained and coated with diclofenac-functionalized biopolymer – poly(3-hydroxyoctanoate) – P(3HO). To the best of our knowledge, studies using P(3HO) as a component in ceramic-polymer based drug delivery system for bone tissue regeneration have not yet been reported. Presented materials were comprehensively investigated by various techniques such as powder X-ray diffraction, scanning electron microscopy with energy dispersive spectroscopy, hydrostatic weighing and compression tests, pH and ionic conductivity measurements, high-performance liquid chromatography and in vitro cytotoxicity studies. The obtained diclofenac-loaded composite was not only characterised by controlled and sustained drug release, but also possessed improved mechanical properties. Moreover, the precipitation of apatite-like forms on its surface was observed after incubation in simulated body fluid, which indicates its bioactive potential. After 24 hours no cytotoxic effect on MC3T3-E1 mouse preosteoblastic cells was confirmed using indirect cytotoxicity studies. Thus, this promising multifunctional composite scaffold can be a promising candidate as an anti-inflammatory drug-delivery system in bone tissue engineering.     

Novel 2-(Adamantan-1-ylamino)Thiazol-4(5H)-One Derivatives and Their Inhibitory Activity towards 11β-HSD1—Synthesis,Molecular Docking and In Vitro Studies

A common mechanism in which glucocorticoids participate is suggested in the pathogenesis of such metabolic diseases as obesity, metabolic syndrome, or Cushing’s syndrome. The enzyme involved in the control of the availability of cortisol, the active form of the glucocorticoid for the glucocorticoid receptor, is 11β-HSD1. Inhibition of 11β-HSD1 activity may bring beneficial results for the alleviation of the course of metabolic diseases such as metabolic syndrome, Cushing’s syndrome or type 2 diabetes. In this work, we obtained 10 novel 2-(adamantan-1-ylamino)thiazol-4(5H)-one derivatives containing different substituents at C-5 of thiazole ring and tested their activity towards inhibition of two 11β-HSD isoforms. For most of them, over 50% inhibition of 11β-HSD1 and less than 45% inhibition of 11β-HSD2 activity at the concentration of 10 µM was observed. The binding energies found during docking simulations for 11β-HSD1 correctly reproduced the experimental IC₅₀ values for analyzed compounds. The most active compound 2-(adamantan-1-ylamino)-1-thia-3-azaspiro[4.5]dec-2-en-4-one (3i) inhibits the activity of isoform 1 by 82.82%. This value is comparable to the known inhibitor-carbenoxolone. The IC₅₀ value is twice the value determined by us for carbenoxolone, however inhibition of the enzyme isoform 2 to a lesser extent makes it an excellent material for further tests.     

Gamut Mapping Spatially Varying Reflectance with an Improved BRDF Similarity Metric

Recent spatially varying reflectance (svBRDF) printing systems can reproduce an input document as a combination of matte, glossy and metallic inks. Due to the limited number of inks, this reproduction process incurs some distortion. In this work, we present an svBRDF gamut mapping algorithm that minimizes distortions in the angular and spatial domains. To preserve a material's perceived variation with lighting and view, we introduce an improved BRDF similarity metric that builds on both experimental results on reflectance perception and on the statistics of natural lighting environments. Our experiments show better preservation of object color and highlights, as validated quantitatively as well as through a perceptual study. As for the spatial domain, we show how to adapt traditional color gamut mapping methods to svBRDFs. Our solution takes into account the contrast between regions, achieving better preservation of textures and edges.     

A Novel Method of Endotoxins Removal from Chitosan Hydrogel as a Potential Bioink Component Obtained by CO2 Saturation

The article presents a new approach in the purification of chitosan (CS) hydrogel in order to remove a significant amount of endotoxins without changing its molecular weight and viscosity. Two variants of the method used to purify CS hydrogels from endotoxins were investigated using the PyroGene rFC Enzymatic Cascade assay kit. The effect of the CS purification method was assessed in terms of changes in the dynamic viscosity of its hydrogels, the molecular weight of the polymer, microbiological purity after refrigerated storage and cytotoxicity against L929 cells based on the ISO 10993-5:2009(E) standard. The proposed purification method 1 (M1) allows for the removal of significant amounts of endotoxins: 87.9–97.6% in relation to their initial concentration in the CS hydrogel without affecting the solution viscosity. Moreover, the final solutions were sterile and microbiologically stable during storage. The M1 purification method did not change the morphology of the L929 cells.