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131.
Nowadays, regenerative medicine faces a major challenge in providing new, functional materials that will meet the characteristics desired to replenish and grow new tissue. Therefore, this study presents new ceramic-polymer composites in which the matrix consists of tricalcium phosphates covered with blends containing a chemically bounded diclofenac with the biocompatible polymer—poly(3-hydroxyoctanoate), P(3HO). Modification of P(3HO) oligomers was confirmed by NMR, IR and XPS. Moreover, obtained oligomers and their blends were subjected to an in-depth characterisation using GPC, TGA, DSC and AFM. Furthermore, we demonstrate that the hydrophobicity and surface free energy values of blends decreased with the amount of diclofenac modified oligomers. Subsequently, the designed composites were used as a substrate for growth of the pre-osteoblast cell line (MC3T3-E1). An in vitro biocompatibility study showed that the composite with the lowest concentration of the proposed drug is within the range assumed to be non-toxic (viability above 70%). Cell proliferation was visualised using the SEM method, whereas the observation of cell penetration into the scaffold was carried out by confocal microscopy. Thus, it can be an ideal new functional bone tissue substitute, allowing not only the regeneration and restoration of the defect but also inhibiting the development of chronic inflammation.  相似文献   
132.
We address the issue of human–robot cohabitation in smart environments. In particular, the presence of humans in a robot’s work space has a profound influence on how the latter should plan its actions. We propose the use of human-aware planning, an approach in which the robot exploits the capabilities of a sensor-rich environment to obtain information about the (current and future) activities of the people in the environment, and plans its tasks accordingly.Here, we formally describe the planning problem behind our approach, we analyze its complexity and we detail the algorithm of our planner. We then show two application scenarios that could benefit from the techniques described. The first scenario illustrates the applicability of human-aware planning in a domestic setting, while the second one illustrates its use for a robotic helper in a hospital. Finally, we present a five hour-long test run in a smart home equipped with real sensors, where a cleaning robot has been deployed and where a human subject is acting. This test run in a real setting is meant to demonstrate the feasibility of our approach to human–robot interaction.  相似文献   
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134.
Elastic-electroactive biological media are sensitive to both mechanical and electric forces. Their active behavior is often associated with the presence of reinforcing fibers and their excitation-contraction coupling is due to the interplay between the passive elastic tissue and the active muscular network. In this paper we focus on the theoretical framework of constitutive equations for viscous electroactive media. The approach is based on the additive decomposition of the Helmholtz free energy accompanied to the multiplicative decomposition of the deformation gradient in elastic, viscous and active parts. We describe a thermodynamically sound scenario that accounts for geometric and material nonlinearities.  相似文献   
135.
This paper describes the design of a Real Time Machine-Vision (MV) Position Sensing System for the problem of Semi-Autonomous Docking within Aerial Refueling (AR) for Unmanned Aerial Vehicles (UAVs). In this effort, techniques and algorithms have been developed and extensively tested in the MATLAB/Simulink® Soft Real-Time environment as well as in Linux/RTAI Hard Real-Time environment. The overall MV software performs several tasks, such as the image acquisition from a real camera, the Feature Extraction (FE) from the acquired image, the Detection and Labeling (DAL) of the features, and the tanker-UAV Pose Estimation (PE). A Cyclic Asynchronous Buffer (CAB) mechanism was implemented for inter-process communication among Real Time and Non Real Time processes. The entire sensing system was tested using an 800 MHz PC-104 computer. The results confirmed the feasibility of executing image processing algorithms in real-time using off-the-shelf commercial hardware to obtain reliable relative position and orientation estimations.  相似文献   
136.
Melatonin content in grape: myth or panacea?   总被引:1,自引:0,他引:1  
Melatonin (N‐acetyl‐5‐methoxytryptamine) was detected by a modified HPLC method and ELISA tests in extracts of eight different Vitis vinifera cultivars, namely Nebbiolo, Croatina, Sangiovese, Merlot, Marzemino, Cabernet Franc, Cabernet Sauvignon and Barbera. Its concentration varied greatly among the cultivars, being the highest in Nebbiolo (0.965 ng g?1) and Croatina (0. 870 ng g?1). Field treatments of grapevine with the plant defence activator benzothiadiazole, greatly improved the melatonin content in berry skin extracts, indicating a possible strategy to raise the content of this important pharmaconutrient in plants, while inducing resistance to pathogens. The finding of this compound in grape suggests that the well‐established pharmaconutritional properties of this fruit are due not only to the presence of polyphenolic nutraceuticals, such as resveratrol, anthocyanins and proanthocyanidins, but also to the powerful antioxidant activity of melatonin. Copyright © 2006 Society of Chemical Industry  相似文献   
137.
The collapse behavior of cylindrical shells pressurized from outside is examined. Attention is focused on tubes of moderate thickness, as required by very deep water pipelines or some innovative nuclear power plant proposals. Their collapse is expected to be dominated by yielding but, because of the decreasing nature of the post-collapse evolution, interaction with instability is likely to be significant enough to demand consideration. At present, no quantitative assessment of such effect is available, because little study has been devoted to tubes in this thickness range.Plasticity–instability interaction is activated by imperfections and to assess their influence on a systematic numerical study is undertaken. Computations produce a meaningful measure of the collapse pressure and it is proposed that the allowable pressure be determined on its basis, by introducing a suitable safety factor. This is chosen so that results reproduce those provided by presently accepted procedures in the well explored and reliable range of medium-thin tubes. When the same factor is applied to thicker tubes, the resulting allowable pressure is significantly higher than the values suggested by codes, which apparently react to the present lack of knowledge by assuming an extremely conservative attitude.  相似文献   
138.
Osteoarthritis (OA) is a degenerative bone disease that involved micro and macro-environment of joints. To date, there are no radical curative treatments for OA and novel therapies are mandatory. Recent evidence suggests the role of miRNAs in OA progression. In our previous studies, we demonstrated the role of miR-31-5p and miR-33a families in different bone regeneration signaling. Here, we investigated the role of miR-31-5p and miR-33a-5p in OA progression. A different expression of miR-31-5p and miR-33a-5p into osteoblasts and chondrocytes isolated from joint tissues of OA patients classified in based on different Kellgren and Lawrence (KL) grading was highlighted; and through a bioinformatic approach the common miRNAs target Specificity proteins (Sp1) were identified. Sp1 regulates the expression of gap junction protein Connexin43 (Cx43), which in OA drives the modification of (i) osteoblasts and chondrocytes genes expression, (ii) joint inflammation cytokines releases and (iii) cell functions. Concerning this, thanks to gain and loss of function studies, the possible role of Sp1 as a modulator of CX43 expression through miR-31-5p and miR-33a-5p action was also evaluated. Finally, we hypothesize that both miRNAs cooperate to modulate the expression of SP1 in osteoblasts and chondrocytes and interfering, consequently, with CX43 expression, and they might be further investigated as new possible biomarkers for OA.  相似文献   
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140.
The aim of this study was the identification of specific proteomic profiles, related to a restored cystic fibrosis transmembrane conductance regulator (CFTR) activity in cystic fibrosis (CF) leukocytes before and after ex vivo treatment with the potentiator VX770. We used leukocytes, isolated from CF patients carrying residual function mutations and eligible for Ivacaftor therapy, and performed CFTR activity together with proteomic analyses through micro-LC–MS. Bioinformatic analyses of the results obtained revealed the downregulation of proteins belonging to the leukocyte transendothelial migration and regulation of actin cytoskeleton pathways when CFTR activity was rescued by VX770 treatment. In particular, we focused our attention on matrix metalloproteinase 9 (MMP9), because the high expression of this protease potentially contributes to parenchyma lung destruction and dysfunction in CF. Thus, the downregulation of MMP9 could represent one of the possible positive effects of VX770 in decreasing the disease progression, and a potential biomarker for the prediction of the efficacy of therapies targeting the defect of Cl transport in CF.  相似文献   
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