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31.
Self assembled monolayers (SAMs) of hydroxamic acids CH3(CH2)nCONHOH with different alkyl length were formed on the carbon steel electrode surface. The corrosion protection properties of the monolayers were examined and characterized by electrochemical polarization curves, electrochemical impedance spectroscopy, X-ray photoelectron spectroscopy (XPS) and contact angle measurements. XPS results showed that the hydroxamic acid molecules adsorbed on the carbon steel surface, and the contact angle values on the modified surface supported the formation of hydrophobic hydroxamic acid SAMs. The results of electrochemical studies showed that the values of the corrosion potential shift towards the positive direction, and anodic currents of the carbon steel dissolution significantly decreases, indicating that hydroxamic acids are anodic inhibitors. However, the chain length and assembling time influence the protection efficiency.  相似文献   
32.
An efficient synthesis of sialic-acid-terminated glycerol dendron to chemically functionalize 2 nm and 14 nm gold nanoparticles (AuNPs) is described. These nanoparticles are highly stable and show high activity towards the inhibition of influenza virus infection. As the binding of the viral fusion protein hemagglutinin to the host cell surface is mediated by sialic acid receptors, a multivalent interaction with sialic-acid-functionalized AuNPs is expected to competitively inhibit viral infection. Electron microscopy techniques and biochemical analysis show a high binding affinity of the 14 nm AuNPs to hemagglutinin on the virus surface and, less efficiently, to isolated hemagglutinin. The functionalized AuNPs are nontoxic to the cells under the conditions studied. This approach allows a new type of molecular-imaging activity-correlation and is of particular relevance for further application in alternative antiviral therapy.  相似文献   
33.
For centuries economists and psychologists have argued that the morality of moral emotions lies in the fact that they stimulate prosocial behavior and benefit others in a person's social environment. Many studies have shown that guilt, arguably the most exemplary moral emotion, indeed motivates prosocial behavior in dyadic social dilemma situations. When multiple persons are involved, however, the moral and prosocial nature of this emotion can be questioned. The present article shows how guilt can have beneficial effects for the victim of one's actions but also disadvantageous effects for other people in the social environment. A series of experiments, with various emotion inductions and dependent measures, all reveal that guilt motivates prosocial behavior toward the victim at the expense of others around—but not at the expense of oneself. These findings illustrate that a thorough understanding of the functioning of emotions is necessary to understand their moral nature. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
34.
Ilona Gaynor and Benedict Singleton , founding partners of design and research studio The Department of No, look beyond the specific technological possibilities of acute accuracy and explore the principle of zero tolerance as an aesthetic of precision. How is such an aesthetic at work when an architectural strategy places a heightened emphasis on the exact placement of objects in space and time? Could the precision in which a single spatial intervention is pursued have more fundamental and far-reaching consequences than we ever imagined?  相似文献   
35.
Due to the limited number of organ donors, 3D printing of organs is a promising technique. Tissue engineering is increasingly using xenogeneic material for this purpose. This study was aimed at assessing the safety of decellularized porcine pancreas, together with the analysis of the risk of an undesirable immune response. We tested eight variants of the decellularization process. We determined the following impacts: rinsing agents (PBS/NH3·H2O), temperature conditions (4 °C/24 °C), and the grinding method of native material (ground/cut). To assess the quality of the extracellular matrix after the completed decellularization process, analyses of the following were performed: DNA concentration, fat content, microscopic evaluation, proteolysis, material cytotoxicity, and most importantly, the Triton X-100 content. Our analyses showed that we obtained a product with an extremely low detergent content with negligible residual DNA content. The obtained results confirmed the performed histological and immuno-fluorescence staining. Moreover, the TEM microscopic analysis proved that the correct collagen structure was preserved after the decellularization process. Based on the obtained results, we chose the most favorable variant in terms of quality and biology. The method we chose is an effective and safe method that gives a chance for the development of transplant and regenerative medicine.  相似文献   
36.
37.
Expression level of Tumor Necrosis Factor—related apoptosis—inducing ligand (TRAIL) receptors is one of the most important factors of TRAIL-mediated apoptosis in cancer cells. We here report for the first time data concerning TRAIL-R1 and TRAIL-R2 receptor expression on RAW264.7 macrophages. Three substances belonging to flavones: chrysin, apigenin and acacetin which differ from their substituents at the 4'' position in the phenyl ring were used in assays because of the variety of biological activities (e.g., anticancer activity) of the polyphenol compounds. The expression of TRAIL-R1 and TRAIL-R2 death receptors on non-stimulated and LPS (lipopolysaccharide)-stimulated macrophages was determined using flow cytometry. We demonstrate that RAW264.7 macrophages exhibit TRAIL-R1 surface expression and that the tested compounds: chrysin, apigenin and acacetin can inhibit TRAIL-R1 death receptor expression level on macrophages.  相似文献   
38.
Rare earth elements are known to improve both mechanical and corrosion properties. However, it highly depends on the final microstructure conditions of prepared material. During extrusion, intermetallic phases may be redistributed, partially dissolved or on the contrary, precipitated. The knowledge of the impact of extrusion on the individual alloys is therefore essential for their application. In this work, three magnesium alloys (Mg-4Y-3RE, Mg-2Y-1Zn, Mg-3Nd-0.5Zn) were prepared by an extrusion process. Microstructure, mechanical and corrosion properties were compared with extruded pure Mg. The advantages and disadvantages of individual alloys are discussed. Based on the obtained results, the Mg-4Y-3RE alloy seems to exert the best mechanical and corrosion properties. Other materials were characterised with anisotropy of mechanical properties and much higher corrosion rate.  相似文献   
39.
Creativity is believed to be helped by an uncluttered state of mind known as flow and as the trend grows towards less immersive displays to produce an uncluttered workplace, we ask the question “Does immersion matter to the flow of distributed group work?”. The aim of this work is to study the impact of level of immersion on workflow and presence during object focussed distributed group work, and to discuss the relevance of these and other factors to supporting flow and creativity. This is approached through a comprehensive literature survey and significant new results. The study attempts to introduce a breadth of factors and relationships as opposed to proving a hypothesis and thus takes a wide qualitative rather than deep quantitative approach to testing and analysis.  相似文献   
40.
An empirical statistical model is described for the use of indoor radon monitoring data as an indicator of the areal radon risk from soil and bedrock. The percentages of future homes expected to have radon concentrations exceeding the design level of 200 Bq/m3 unless constructed to provide protection against the entry of radon were assessed. The radon prognosis was made for different subareas, soil types and foundation types. This kind of report is used by the health and building authorities. In this study, 2689 indoor radon measurements were made in one of Finland's most radon-prone areas, consisting of eleven municipalities with a total area of 4600 km2 and a population of 186,000. Radon concentrations were seasonally adjusted. Data on the location, geology and construction of buildings were determined from maps and questionnaires. The measurements covered different kinds of geological units in the area. The radon risk is highest in the gravel-dominated subarea in an ice-marginal formation and lowest in the northern half of the area in buildings constructed on bedrock. In these two areas, the design level of 200 Bq/m3 would be exceeded in 99% and 39% of new houses with slab-on-grade.  相似文献   
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