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1.
We address the problem of multi-label classification in heterogeneous graphs, where nodes belong to different types and different types have different sets of classification labels. We present a novel approach that aims to classify nodes based on their neighborhoods. We model the mutual influence of nodes as a random walk in which the random surfer aims at distributing class labels to nodes while walking through the graph. When viewing class labels as “colors”, the random surfer is essentially spraying different node types with different color palettes; hence the name Graffiti of our method. In contrast to previous work on topic-based random surfer models, our approach captures and exploits the mutual influence of nodes of the same type based on their connections to nodes of other types. We show important properties of our algorithm such as convergence and scalability. We also confirm the practical viability of Graffiti by an experimental study on subsets of the popular social networks Flickr and LibraryThing. We demonstrate the superiority of our approach by comparing it to three other state-of-the-art techniques for graph-based classification.  相似文献   
2.
New gold–molybdena catalysts supported on ceria and ceria–alumina in reaction of complete benzene oxidation were studied. The catalysts were characterized by means of XRD, TPR, XPS and Raman spectroscopy. High and stable catalytic activity was established in the temperature region 200–240 °C. The presence of gold causes a modification in ceria structure leading to an increase of Ce3+ and oxygen vacancies formation. The loading of Al3+ increases additionally the oxygen vacancies, while a tendency of decrease of Ce3+ amount was observed. The presence of alumina results also in a larger share of active oxygen species proved by analysis of O 1s XPS spectra. The differences in the activities within the starting temperature range (150–180 °C) and in the region of 100% conversion (200–240 °C) could be explained by supposing that in the LT region the electron transfer between nanosized gold and ceria particles via oxygen vacancies has a crucial role. In the HT region the oxygen mobility, provoked by the defective structure of ceria due to the presence of Al3+, becomes of prevailing importance. It was also concluded that alumina prevents the gold and ceria agglomeration, which is the main factor to avoid deactivation under extreme reaction conditions.  相似文献   
3.
A state of the art review of Reactor Dosimetry used for reactor pressure vessel irradiation damage assessment and lifetime evaluation of the Russian type VVER reactors is presented. The necessity of prospective studies in Reactor Dosimetry for improvements that will reduce the neutron fluence uncertainty and in this way to substantiate the extension of NPP lifetime is summarized by specialists in Reactor Dosimetry from countries operating VVER reactors such as Russia, Ukraine, Czech Republic, Finland, Hungary, and Bulgaria, together with specialists from Western European countries such as France, Spain, Germany, Belgium, The Netherlands, and UK, operating PWR and BWR type reactors.  相似文献   
4.
Two approaches for purification of rosmarinic acid extracts, obtained from Lavandula vera MM cell biomass were investigated: adsorption on different Amberlite XAD resins and extraction with ethylacetate. Results showed that when ethylacetate extraction was used, 18.7 times higher level of purity compared to initial material was achieved. Similarly the obtained preparations from adsorption on Amberlite XAD-7 resin and elution with 80% ethanol contained 29.8% rosmarinic acid, which is 7.7 times higher purity compared to initial material. The precipitation of rosmarinic acid as Ca-rosmarinate was investigated as well. The obtained rosmarinic acid preparations were with low yield (34% of rosmarinic acid fell into sediment).  相似文献   
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6.
Results are reported from the comparative investigations of kidney concentration function by urine specific gravity and its osmolatity of 58 patients with arterial hypertension. Significant differences were found in more of the half of the patients. On the base of certain theoretical prerequisites and possibilities of technical errors was concluded that the determination of the maximal urine osmolality is a more reliable and more accurate index for the actual renal concentration ability. Urine specific gravity can be used in the everyday clinical practice due to the more convenient and easier determination. Urine osmolality must be used predominantly in scientific-clinical studies.  相似文献   
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For micro replication, the base of a die should be ductile and the surface layer that will undergo processing should have a good machining response to various tool-making processes. At the same time, the resulting working surfaces of the tooling cavities should be hard; having low roughness, low wettability and high erosion resistance. To achieve such diverse properties, nano-crystalline CrC coatings deposited onto 12% Cr tool steel were investigated in this research. To verify the properties of such coatings various metallographic techniques were applied. In particular, the corrosion resistance was studied by means of potentiodynamic anodic polarisation. A scanning transmission electron microscopy analysis of the structure was performed on samples prepared with focused ion beam (FIB) machining. The mechanical properties and grain size distribution were determined and statistically analysed. In addition, X-ray diffraction, scanning electron microscopy and atomic force microscopy were used in studying the surface properties of these coatings. To investigate the response of the CrC coatings to micro- and nano-structuring technologies with high specific energy, a series of rectangular trenches were produced by FIB milling. The effects of the ion beam current, exposure time and ion fluence on the sputtering yield and roughness of the produced micro-structures were especially investigated. Some essential parameter windows for performing FIB milling with relatively high sputtering rates, higher than 1?µm/min, and at the same time achieving the best possible surface integrity were determined during the experiments.  相似文献   
9.
Our objective is to reveal the molecular mechanism of the anti-inflammatory action of low-molecular-weight heparin (LMWH) based on its influence on the activity of two key cytokines, IFNγ and IL-6. The mechanism of heparin binding to IFNγ and IL-6 and the resulting inhibition of their activity were studied by means of extensive molecular-dynamics simulations. The effect of LMWH on IFNγ signalling inside stimulated WISH cells was investigated by measuring its antiproliferative activity and the translocation of phosphorylated STAT1 in the nucleus. We found that LMWH binds with high affinity to IFNγ and is able to fully inhibit the interaction with its cellular receptor. It also influences the biological activity of IL-6 by binding to either IL-6 or IL-6/IL-6Rα, thus preventing the formation of the IL-6/IL-6Rα/gp130 signalling complex. These findings shed light on the molecular mechanism of the anti-inflammatory action of LMWH and underpin its ability to influence favourably conditions characterised by overexpression of these two cytokines. Such conditions are not only associated with autoimmune diseases, but also with inflammatory processes, in particular with COVID-19. Our results put forward heparin as a promising means for the prevention and suppression of severe CRS and encourage further investigations on its applicability as an anti-inflammatory agent.  相似文献   
10.
The application of Calorimetric Low-Temperature Detectors (CLTDs) has been proposed at the Heavy-Ion TRAP facility HITRAP which is currently being installed at the Helmholtz Research Center for Heavy Ion Research GSI. This cold ion trap setup will allow the investigation of X-rays from ions practically at rest, for which the excellent energy resolution of CLTDs can be used to its full advantage. However, the relatively low intensities at HITRAP demand larger solid angles and an optimized cryogenic setup. The influence of external magnetic fields has to be taken into account. CLTDs will also be a substantial part of the instrumental equipment at the future Facility for Antiproton and Heavy Ion Research (FAIR), for which a wide variety of high-precision X-ray spectroscopy experiments has been proposed. This contribution will give an overview on the chances and challenges for the application of CLTDs at HITRAP as well as perspectives for future experiments at the FAIR facility.  相似文献   
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