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61.
The paper addresses the Be Responsible platform, a representative example of human-centric sensing network which, relying on the Info-Communication and Internet of Things concepts, aims to improve the communication between citizens, on one side, and government authorities, on the other side, with the purpose of resolving various problems encountered in a modern society. A widespread network of human-centric smartphone devices and PCs has been used as a valuable source of data collected and processed in order to trigger adequate actions upon problem resolving. In this way, humans acting as sensor operators and data sources become a powerful factor in improving their society. The Be Responsible platform enables the people to report the irregularities in various aspects of their social life (grey economy, misuse of government vehicles, ecology, traffic), and hence to take active part in resolving them. It also promotes positive and responsible social and institutional behavior, which has to be nurtured in any society seeking progress. The number of submitted reports as well as the money collected from the fine revenues and subsequently invested in projects of social good, undoubtedly prove that what could not be achieved through years of traditional government-led policy approach, was achieved in months of citizen engagement.  相似文献   
62.
Classical electrostriction, describing a second‐order electromechanical response of insulating solids, scales with elastic compliance, S, and inversely with dielectric susceptibility, ε. This behavior, first noted 20 years ago by Robert Newnham, is shown to apply to a wide range of electrostrictors including polymers, glasses, crystalline linear dielectrics, and relaxor ferroelectrics. Electrostriction in fluorite ceramics of (Y, Nb)‐stabilized δ‐Bi2O3 is examined with 16%–23% vacant oxygen sites. Given the values of compliance and dielectric susceptibility, the electrostriction coefficients are orders of magnitude larger than those expected from Newnham's scaling law. In ambient temperature nanoindentation measurements, (Y, Nb)‐stabilized δ‐Bi2O3 displays primary creep. These findings, which are strikingly similar to those reported for Gd‐doped ceria, support the suggestion that ion conducting ceramics with the fluorite structure, a large concentration of anion vacancies and anelastic behavior, may constitute a previously unknown class of electrostrictors.  相似文献   
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64.
A novel adaptive clipping technique for filtering a constant amplitude frequency modulated (FM) signal embedded in non-Gaussian noise is proposed. It is based on the analysis and processing of the estimate of probability density function of a FM signal realization. As a result, modifications of two robust estimators of FM signal amplitude are proposed. It is shown that these estimators can be used for Gaussian and non-Gaussian heavy-tail environments. The proposed clipping technique can exploit one or another obtained robust estimate of the signal amplitude for adaptive setting a threshold. Analysis of signal estimate accuracy for different noise environments is carried out. Comparative analysis of the obtained methods and known approaches based on scanning window nonlinear filtering and optimal robust L-DFT form is performed. It is demonstrated that the usage of clipping-based technique leads to the considerable improvement of the FM signal filtering efficiency in comparison to the aforementioned known approaches for different noise environments and a wide range of input SNR values.  相似文献   
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66.
Glioblastoma (GBM) is the most common and deadly primary brain tumor in adults. Understanding GBM pathobiology and discovering novel therapeutic targets are critical to finding efficient treatments. Upregulation of the lysosomal cysteine carboxypeptidase cathepsin X has been linked to immune dysfunction and neurodegenerative diseases, but its role in cancer and particularly in GBM progression in patients is unknown. In this study, cathepsin X expression and activity were found to be upregulated in human GBM tissues compared to low-grade gliomas and nontumor brain tissues. Cathepsin X was localized in GBM cells as well as in tumor-associated macrophages and microglia. Subsequently, potent irreversible (AMS36) and reversible (Z7) selective cathepsin X inhibitors were tested in vitro. Selective cathepsin X inhibitors decreased the viability of patient-derived GBM cells as well as macrophages and microglia that were cultured in conditioned media of GBM cells. We next examined the expression pattern of neuron-specific enzyme γ-enolase, which is the target of cathepsin X. We found that there was a correlation between high proteolytic activity of cathepsin X and C-terminal cleavage of γ-enolase and that cathepsin X and γ-enolase were colocalized in GBM tissues, preferentially in GBM-associated macrophages and microglia. Taken together, our results on patient-derived material suggest that cathepsin X is involved in GBM progression and is a potential target for therapeutic approaches against GBM.  相似文献   
67.
Plant-mediated RNA interference (RNAi) holds great promise for insect pest control, as plants can be transformed to produce double-stranded RNA (dsRNA) to selectively down-regulate insect genes essential for survival. For optimum potency, dsRNA can be produced in plant plastids, enabling the accumulation of unprocessed dsRNAs. However, the relative effectiveness of this strategy in inducing an RNAi response in insects using different feeding mechanisms is understudied. To investigate this, we first tested an in vitro-synthesized 189 bp dsRNA matching a highly conserved region of the v-ATPaseA gene from cotton mealybug (Phenacoccus solenopsis) on three insect species from two different orders that use leaf-chewing, lacerate-and-flush, or sap-sucking mechanisms to feed, and showed that the dsRNA significantly down-regulated the target gene. We then developed transplastomic Micro-tom tomato plants to produce the dsRNA in plant plastids and showed that the dsRNA is produced in leaf, flower, green fruit, red fruit, and roots, with the highest dsRNA levels found in the leaf. The plastid-produced dsRNA induced a significant gene down-regulation in insects using leaf-chewing and lacerate-and-flush feeding mechanisms, while sap-sucking insects were unaffected. Our results suggest that plastid-produced dsRNA can be used to control leaf-chewing and lacerate-and-flush feeding insects, but may not be useful for sap-sucking insects.  相似文献   
68.
Co/CeO2 (Co 7.5 wt.%), Ni/CeO2 (Ni 7.5 wt.%) and Co–Ni/CeO2 (Co 3.75 wt.%, Ni 3.75 wt.%) catalysts were prepared by surfactant assisted co-precipitation method. Samples were characterized by X-Ray diffraction, BET surface areas measurements, temperature programmed reduction and tested for the dry reforming of methane CH4 + CO2 → 2CO + 2H2 in the temperature range 600–800 °C with a CH4:CO2:Ar 20:20:60 vol.% feed mixture and a total flow rate of 50 cm3 min−1 (GHSW = 30,000 mL g−1 h−1). The bimetallic Co–Ni/CeO2 catalyst showed higher CH4 conversion in comparison with monometallic systems in the whole temperature range, being 50% at 600 °C and 97% at 800 °C. H2/CO selectivity decreased in the following order: Co–Ni/CeO2 > Ni/CeO2 > Co/CeO2. Carbon deposition on spent catalysts was analyzed by thermal analysis (TG-DTA). After 20 h under stream at 750 °C, cobalt-containing catalysts, Co/CeO2 and Co–Ni/CeO2, showed a stable operation in presence of a deposited amorphous carbon of 6 wt.%, whereas Ni/CeO2 showed an 8% decrease of catalytic activity due to a massive presence of amorphous and graphitic carbon (25 wt.%).  相似文献   
69.

Rational use of cars in smart cities can represent an economical and cheaper way to decrease the quantity of cars on the roads to better the life quality of the populations. This paper presents a low-cost deployment proposal called “URCa project” to reach these goals and proposes a paradigm change by sharing the cars considering some logistic aspects including car ride mechanism. Technical feasibility to deploy this solution was checked by means of a proof of concept. The concept was proven by passenger counting and license plate that are essential information in this solution were obtained taking photographs, applying two types of recognition algorithms and sending the results to be stored and evaluated by analytic data processes of a transit regulatory agency showing that this project is technically viable. The low-cost solution was justified by a financial analysis based on both costs (URCa solution and a bridge) that has shown a ratio of 1:10,000.

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70.
Intelligent Service Robotics - GidaBot is an application designed to set up and run a heterogeneous team of robots to act as tour guides in multi-floor buildings. Although the tours can go through...  相似文献   
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