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391.
Effective and timely health monitoring of wind turbine gearboxes and generators is essential to reduce the costs of operations and maintenance activities, especially offshore. This paper presents a scalable and lightweight convolutional neural network (CNN) framework using high-dimensional raw condition monitoring data for the automatic detection of multiple wind turbine electromechanical faults. The proposed approach leverages the potential of combining information from a variety of signals to learn features and to discriminate the types of fault and their severity. As a result of the CNN layers used to extract features from the signals, this architecture works in the time domain and can digest high-resolution multi-sensor data streams in real-time. To overcome the inherent black-box nature of AI models, this research proposes two interpretability techniques, multidimensional scaling and layer-wise relevance propagation, to analyse the proposed model's inner-working and identify the signal features relevant for fault classification. Experimental results show high performance and classification accuracies above 99.9% for all fault cases tested, demonstrating the efficacy of the proposed fault-detection system. 相似文献
392.
The occurrence of the fumonisins B(1) and B(2) in maize-based food products marketed in Italy was examined. A simply and reliable chromatographic method with fluorimetric detection and postcolumn o-phtalaldehyde derivatization was used for a monitoring of 100 samples (8 flours, 21 corn-meal, 16 snacks, 7 maize samples, 13 gluten-free products, and 35 corn-flakes) bought in local supermarkets during the years 2008 and 2009. The presence of both fumonisins B(1) and B(2), at a concentration higher than 15 μg/kg, was observed in all samples of corn-meal and maize-flour, in 75% of snacks, in 57% of maize samples, in 54% of gluten-free products, and in 29% of corn-flakes. A total of 7 samples including 4 corn-meals, 2 maize-flours, and 1 maize showed a value exceeding the maximum level fixed in the Regulation 1126/2007/EC; no positive sample was observed in corn-flakes, snacks, and gluten-free foods. Fumonisins contamination, on the whole range of maize-based food products analyzed, emphasizes the need of improve agricultural practices, and increase official control and monitoring studies. 相似文献
393.
High Saturated Fat Diet Alters the Lipid Composition of Triacylglycerol and Polar Lipids in the Femur of Dam and Offspring Rats 下载免费PDF全文
Paula M. Miotto Laura M. Castelli Foyinsola Amoye Wendy E. Ward Paul J. LeBlanc 《Lipids》2015,50(6):605-610
Previous work has shown that dietary lipids alter femur lipid composition. Specifically, we have shown that exposure to high saturated fatty acid (SFA) diets in utero, during suckling, or post‐weaning alters femur total lipid composition, resulting in higher percent bone mass in males and females and bone mineral density (BMD) in female offspring with no effect on bone mineral outcomes in dams. Comparatively, high n‐3 polyunsaturated fatty acid (PUFA) diets increase femur polar (PL) lipid n‐3 content, which has been associated with increased bone mineral content and strength. However, the extent that PL or triacylglycerol (TAG) lipids change with high SFA diets is unknown. The current investigation examined the influence of a high SFA diet (20 % lard by weight) on femur PL and TAG lipid composition in 5‐month old female Wistar rats (fed high SFA diet from age 28 days onwards; dams) and their 19‐day old offspring (exposed to high SFA in utero and during suckling; pups). High SFA exposure resulted in increased monounsaturates and decreased n‐3 and n‐6 PUFA in the TAG fraction in both dams and pups, and higher SFA and n‐6:n‐3 ratio in dams only. The PL fraction showed decreased n‐6 PUFA in both dams and pups. The magnitude of the diet‐mediated responses, specifically TAG 18:1 and PL n‐6 PUFA, may have contributed to the previously reported altered BMD, which was supported with correlation analysis. Future research should investigate the relationship of diet‐induced changes in bone lipids on bone structure, as quantified through micro‐computed tomography. 相似文献
394.
Hamed Hajizadeh Seyed Jamaleddin Peighambardoust Seyed Hadi Peighambardoust Donatella Peressini 《Journal of food science》2020,85(4):1193-1202
In this study, starch-based films incorporating metal oxide (MO2) nanoparticles (NPs) of TiO2 and SiO2 (at a concentration of 1 to 4 wt. %) were produced by solution casting method. In order to exhibit antimicrobial properties, MO2 NPs were modified by synthesizing silver (Ag) ions over the NPs using cationic adsorption method. Ag ions were then reduced to metallic Ag by sodium borohydride solution. Scanning electron microscopy showed a smooth surface for the pure starch film. Incorporating MO2@Ag NPs in the films increased surface roughness with agglomerated NPs within starch matrix. Energy dispersive X-ray analysis exhibited a uniform dispersion of Ag-loaded MO2 NPs, which increases surface contact between these NPs and the biopolymer matrix leading to improved physical and mechanical properties of the resulting films. With increasing in the NPs concentrations, the tensile strength and elongation at break % of the films increased and decreased, respectively. Incorporating MO2@Ag NPs into starch matrix decreased solubility in water and water vapor permeability of the obtained films, and significantly inhibited the growth of Escherichia coli and Staphylococcus aureus. The most antibacterial effect was obtained for the films containing higher weight concentrations of Ag-loaded SiO2-NPs. 相似文献
395.
Lawrence D. Bergman Jerre Shoudt Vittorio Castelli Chung-Sheng Li Loey Knapp 《International Journal on Digital Libraries》1999,2(2-3):178-189
In this paper, we describe a new interface for querying multimedia digital libraries and an interface building framework.
The interface employs a drag-and-drop style of interaction and combines a structured natural-language style query specification
with reusable multimedia objects. We call this interface DanDMM, short for “drag-and-drop multimedia”. DanDMM interfaces capture
the syntax of the underlying query language, and dynamically reconfigure to reflect the contents of the data repository.
A distinguishing feature of DanDMM is its ability to synthesize integrated interfaces that incorporate both example-based
specification using multimedia objects, and traditional techniques including keyword, attribute, and free text-based search.
We describe the DanDMM-builder, a framework for synthesizing DanDMM interfaces, and give several examples of interfaces that
have been constructed using DanDMM-builder, including a remote-sensing library application and a video digital library.
Received: 15 December 1997 / Revised: June 1999 相似文献
396.
Pier Luigi Beltrame Antonella Castelli Germano Munaretto Maurizio Canetti Alberto Seves 《应用聚合物科学杂志》1997,65(9):1659-1665
Ternary blends containing polypropylene (PP), poly(1-butene) (PB), and hydrogenated oligo(cyclopentadiene) (HOCP) have been studied using microscopic calorimetric and dynamic mechanical techniques, with no phase separation having been observed in the melt for all the considered compositions. The morphology of the crystallized blends and spherulite growth rate of the PP component appeared to be influenced by the blend composition. The presence of one or two Tgs revealed by dynamic mechanical thermal analysis (DMTA) on quenched or crystallized blends has suggested that demixing phenomena can occur during the crystallization of the components. The blend composition has been found to affect the overall crystallization rate and the equilibrium melting temperature of the PP component. A parameter describing the enthalpic interactions between the PP component and the diluent fraction evidenced that the addition of HOCP to PP and PB increases the stability of the ternary blend. The above results suggest that the three components can form a miscible blend in the melt. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65:1659–1665, 1997 相似文献
397.
Pier Luigi Beltrame Antonella Castelli Mario Di Pasquantonio Maurizio Canetti Alberto Seves 《应用聚合物科学杂志》1996,60(4):579-590
Binary low-density polythylene/polyamide 6 and ternary low-density polyethylene/polypropylene/polyamide 6 blends were prepared by melt mixing, without and with the addition of two different commercial products [poly(ethylere-co-buthylacrylate-co-maleic anhydride) and poly(ethylene-co-vinylacetate) grafted with maleic anhydride] used as interfacial modifiers. More precisely, the polypropylene was a propylene/ethylene random copolymer, containg 6% by weight of ethylene. The polyamide 6/interfacial agent and polyethylene/ interfacial agent systems were also considered. Differential scanning calorimetry, microscopic observations—together with chemical etchings—and mechanical tests supported the occurrence of strong interactions at the interface, especially when using the buthyl acrylate-based agent. The compatibilizing effect of the interfacial agents was also analyzed in the light of interfacial tension determinations. Eventually, low-density polyethylene modifications induced by compatibilization were studied carrying out WAXD analysis. © 1996 John Wiley & Sons, Inc. 相似文献
398.
Serena Redaelli Donatella Conconi Elena Sala Nicoletta Villa Francesca Crosti Gaia Roversi Ilaria Catusi Chiara Valtorta Maria Paola Recalcati Leda Dalpr Marialuisa Lavitrano Angela Bentivegna 《International journal of molecular sciences》2022,23(6)
Improvements in microarray-based comparative genomic hybridization technology have allowed for high-resolution detection of genome wide copy number alterations, leading to a better definition of rearrangements and supporting the study of pathogenesis mechanisms. In this study, we focused our attention on chromosome 8p. We report 12 cases of 8p rearrangements, analyzed by molecular karyotype, evidencing a continuum of fragility that involves the entire short arm. The breakpoints seem more concentrated in three intervals: one at the telomeric end, the others at 8p23.1, close to the beta-defensin gene cluster and olfactory receptor low-copy repeats. Hypothetical mechanisms for all cases are described. Our data extend the cohort of published patients with 8p aberrations and highlight the need to pay special attention to these sequences due to the risk of formation of new chromosomal aberrations with pathological effects. 相似文献
399.
Giorgio Tiecco Samuele Storti Melania Degli Antoni Emanuele Foc Francesco Castelli Eugenia Quiros-Roldan 《International journal of molecular sciences》2022,23(4)
The Coronavirus disease 2019 (COVID-19) pandemic poses a great threat to global public health. The original wild-type strain of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has genetically evolved, and several variants of concern (VOC) have emerged. On 26 November 2021, a new variant named Omicron (B.1.1.529) was designated as the fifth VOC, revealing that SARS-CoV-2 has the potential to go beyond the available therapies. The high number of mutations harboured on the spike protein make Omicron highly transmissible, less responsive to several of the currently used drugs, as well as potentially able to escape immune protection elicited by both vaccines and previous infection. We reviewed the latest publication and the most recent available literature on the Omicron variant, enlightening both reasons for concern and high hopes for new therapeutic strategies. 相似文献
400.
Maria Dolci Lucia Signorini Sarah DAlessandro Federica Perego Silvia Parapini Michele Sommariva Donatella Taramelli Pasquale Ferrante Nicoletta Basilico Serena Delbue 《International journal of molecular sciences》2022,23(7)
In the novel pandemic of Coronavirus Disease 2019, high levels of pro-inflammatory cytokines lead to endothelial activation and dysfunction, promoting a pro-coagulative state, thrombotic events, and microvasculature injuries. The aim of the present work was to investigate the effect of SARS-CoV-2 on pro-inflammatory cytokines, tissue factor, and chemokine release, with Human Microvascular Endothelial Cells (HMEC-1). ACE2 receptor expression was evaluated by western blot analysis. SARS-CoV-2 infection was assessed by one-step RT-PCR until 7 days post-infection (p.i.), and by Transmission Electron Microscopy (TEM). IL-6, TNF-α, IL-8, IFN-α, and hTF mRNA expression levels were detected by RT-PCR, while cytokine release was evaluated by ELISA. HMEC-1 expressed ACE2 receptor and SARS-CoV-2 infection showed a constant viral load. TEM analysis showed virions localized in the cytoplasm. Expression of IL-6 at 24 h and IFN-α mRNA at 24 h and 48 h p.i. was higher in infected than uninfected HMEC-1 (p < 0.05). IL-6 levels were significantly higher in supernatants from infected HMEC-1 (p < 0.001) at 24 h, 48 h, and 72 h p.i., while IL-8 levels were significantly lower at 24 h p.i. (p < 0.001). These data indicate that in vitro microvascular endothelial cells are susceptible to SARS-CoV-2 infection but slightly contribute to viral amplification. However, SARS-CoV-2 infection might trigger the increase of pro-inflammatory mediators. 相似文献