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91.
92.
Carolina Simó Clara Ibá?ez Alberto Valdés Alejandro Cifuentes Virginia García-Ca?as 《International journal of molecular sciences》2014,15(10):18941-18966
Metabolomic-based approaches are increasingly applied to analyse genetically modified organisms (GMOs) making it possible to obtain broader and deeper information on the composition of GMOs compared to that obtained from traditional analytical approaches. The combination in metabolomics of advanced analytical methods and bioinformatics tools provides wide chemical compositional data that contributes to corroborate (or not) the substantial equivalence and occurrence of unintended changes resulting from genetic transformation. This review provides insight into recent progress in metabolomics studies on transgenic crops focusing mainly in papers published in the last decade. 相似文献
93.
94.
David González G. Mario García-Lozano Silvia Ruiz Dong Seop Lee 《Wireless Networks》2014,20(6):1369-1386
The explosive growth of cellular networks makes their deployment and maintenance more and more complex, time consuming, and expensive. Self-Organizing Networks have been recognized as a promising way to alleviate this problem by minimizing human intervention in such processes. This paper introduces a novel multiobjective framework, based on evolutionary optimization, aiming at improving network performance and users Quality of Service. By tuning the transmitted power at each cell, average intercell interference levels are minimized. The design of the proposed scheme is feasible for distributed implementations in Long Term Evolution (LTE) and LTE-Advanced networks and its operation is compatible with current specifications. The framework is able to provide effective network-specific optimization and obtained results show that gains in terms of network capacity and cell edge performance are 5 and 10 %, respectively. Energy savings always accompanied such enhancements with reductions up to 35 %. 相似文献
95.
Large volumes of residual biomass (mainly peels and seeds) are generated by tomato industrial processing plants. After adequate drying and densification operations, those biomass wastes might be used for livestock food production, for lycopene extraction or even as fuel supply for thermal applications.The process described in the present paper is the manufacturing of 6 mm diameter pellets from tomato waste samples obtained from industrial processing plants. As a previous step, the samples were dehydrated to five different values of moisture content (20, 25, 29, 34 and 38 wt% w.b. approximately). Bulk and particle densities, hardness and durability of pellets were significantly influenced by the initial moisture content of the biomass raw materials, as well as by the subsequent reductions of such moisture content after pelletizing operations and storage periods. Increases of 21%, 41% and 67% in moisture content of the feeding biomass material – with respect to the lower value of the operating range, i.e. 20 wt% w.b. – were observed to yield the following percentage increments in a series of physical properties of pellets, respectively: 14%, 25% and 50% in bulk density; 6%, 16% and 18% in particle density; 225%, 1737% and 3575% in hardness; 8%, 44% and 88% in durability. Nevertheless, higher increments in moisture content of feeding material led to significantly lower values of the aforementioned properties – not to mention technical operating problems due to roller skidding in the pelletizing device.Pellets obtained from raw biomass (peels and seeds) with 34 wt% initial moisture content (9% final moisture content of pellets) were regarded as those with the most suitable configuration: durability 91.2%, hardness up to 88 N and energy density approaching 8 GJ/m3. 相似文献
96.
Francisco J. Fernandez-Luque David Pérez Félix Martínez Ginés Domènech Isabel Navarrete Juan Zapata Ramón Ruiz 《Ad hoc Networks》2013,11(3):907-925
DIA (Dispositivo Inteligente de Alarma, in Spanish) is an AAL (Ambient Assisted Living) system that allows to infer a potential dangerous action of an elderly person living alone at home. This inference is obtained by a specific sensorisation with sensor nodes (portables and fixes) and a reasoning layer embedded in a PC that learns of the users behaviour patterns and advices when actual one differs significantly of the normal patterns. In AAL systems, energy is a limited resource therefore sensor devices need to be properly managed to conserve energy. In this paper, we introduce the design and implementation of innovative and specific mechanisms at the sensory layer middleware which is capable of, first to discriminate spurious motion detections assuming that these signals do not resemble the patterns of real motion detections and, second to reduce the dynamics of messages by a sensor signal processing in order to compress the whole information in one single event. The middleware achieves power saving by modifying the raw information from sensors and adapting it to the predefined semantic of the reasoning layer. It manages the important task of data processing from sensors (raw information), and transfers the pre-processed information into the top layer of reasoning in a more energy efficient way. We also address the trade-off between reducing power consumption and reducing delay for incoming data. We present results from experiments using our implementation of these mechanisms at the middleware that comprises from node firmware to the PC driver. The number of messages of the proposed method with respect to the raw data is reduced by approximately 98.5%. The resources used in the PIR signal processing is reduced by approximately 85%. The resulting delay introduced is small (10–19 s) but system dynamics is slow enough to avoid contextualisation errors or reduction of system performance. We consider these results as very satisfactory. 相似文献
97.
98.
Serban N. Stamatin Maryam Borghei Shuang Ma Andersen Sune Veltze Virginia Ruiz Esko Kauppinen Eivind M. Skou 《International Journal of Hydrogen Energy》2014
Commercially available graphitized carbon nanofibers and multi-walled carbon nanotubes, two carbon materials with very different structure, have been functionalized in a nitric–sulfuric acid mixture. Further on, the materials have been platinized by a microwave assisted polyol method. The relative degree of graphitization has been estimated by means of Raman spectroscopy and X-ray diffraction while the relative concentration of oxygen containing groups has been estimated by X-ray photoelectron spectroscopy, which resulted in a graphitic character trend: Pt/GNF > Pt/F-GNF ? Pt/MWCNT > Pt/F-MWCNT. Transmission electron microscopy showed that the Pt particle size is around 3 nm for all samples, which was similar to the crystallite size obtained by X-ray diffraction. The activity towards electrochemical reduction of oxygen has been quantified using the thin-film rotating disk electrode, which has shown that all the samples have a better activity than the commercially available electrocatalysts. The trend obtained for the graphitic character maintained for the electrochemical activity, while the reverse trend has been obtained for the accelerated ageing test. Long-term potential cycling has demonstrated that the functionalization improves the stability for multi-walled carbon nanotubes, at the cost of decreased activity. 相似文献
99.
Jin Pan Julian Tang Miguela Caniza Jean-Michel Heraud Evelyn Koay Hong Kai Lee Chun Kiat Lee Yuguo Li Alejandra Nava Ruiz Carlos Francisco Santillan-Salas Linsey C. Marr 《Indoor air》2021,31(6):2281-2295
The incidence of several respiratory viral infections has been shown to be related to climate. Because humans spend most of their time indoors, measures of indoor climate, rather than outdoor climate, may be better predictors of disease incidence and transmission. Therefore, understanding the relationship between indoor and outdoor climate will help illuminate their influence on the seasonality of diseases caused by respiratory viruses. Indoor-outdoor relationships between temperature and humidity have been documented in temperate regions, but little information is available for tropical regions, where seasonal patterns of respiratory viral diseases differ. We have examined indoor-outdoor correlations of temperature, relative humidity (RH), and absolute humidity (AH) over a 1-year period in each of seven tropical cities. Across all cities, the average monthly indoor temperature was 25 ± 3°C (mean ± standard deviation) with a range of 20–30°C. The average monthly indoor RH was 66 ± 9% with a range of 50–78%, and the average monthly indoor AH was 15 ± 3 g/m3 with a range of 10–23 g/m3. Indoor AH and RH were linearly correlated with outdoor AH when the air conditioning (AC) was off, suggesting that outdoor AH may be a good proxy of indoor humidity in the absence of AC. All indoor measurements were more strongly correlated with outdoor measurements as distance from the equator increased. Such correlations were weaker during the wet season, especially when AC was in operation. These correlations will provide insight for assessing the seasonality of respiratory viral infections using outdoor climate data, which is more widely available than indoor data, even though transmission of these diseases mainly occurs indoors. 相似文献
100.
This paper investigates the manufacturing distortion of curved composite parts manufactured by a new Liquid Composite Molding (LCM) process called Flexible Injection (FI). This technique uses a deformable tool to speed up the fabrication but may generate manufacturing defects when strongly curved shapes are processed. The goal of the study is to evaluate the impact of such heterogeneities on the dimensional stability of the product. Curved components were first manufactured with varying processing conditions to achieve a wide range of layup quality. The shape stability of the samples was then recorded as a function of temperature to measure the thermoelastic component of distortion and experimental results were compared with predictions made by two modeling techniques. Under certain conditions, manufacturing defects can significantly affect the distortion behavior. This suggests that a robust preforming procedure is of primary importance to produce curved parts by Flexible Injection with a high level of repeatability. 相似文献