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71.
Daniel A. R. Chaves Renan V. B. Carvalho Helder A. Pereira Carmelo J. A. Bastos-Filho Joaquim F. Martins-Filho 《Photonic Network Communications》2012,24(3):237-251
In this paper, we propose two strategies for sparse regenerator placement (RP) in translucent optical networks, named most used regenerator placement (MU-RP), and most simultaneous used regenerator placement (MSU-RP). Our proposals are compared to well known RP algorithms presented in literature for two different network topologies for different network loads, distribution of load along the networks and number of translucent nodes. MSU-RP presented remarkable results and outperformed all previous approaches in all cases, while MSU-RP obtained a slightly superior or similar performance when compared to previous approaches presented in the literature. 相似文献
72.
Annamaria Passantino Carmelo Russo Letizia Passantino Francesca Conte 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2011,6(4):427-434
Ivermectin (IVM) is a macrocyclic disaccharide anthelmintic agent with broad-spectrum antiparasitic action. It is used for controlling internal and external parasites in food-producing animals (bovine, swine and equine species), including donkey. This drug is included in Council Regulation (EEC) 2377/90, annex I, with Maximum Residue Limit (MRL) ranging from 15 to 100???g?kg?1 depending on the species. The pharmacokinetic characteristics of IVM mainly depend on the animal species, formulation and route of administration. Due to its high lipophilicity it accumulates in milk of food producing animals. Detailed IVM pharmacokinetic studies were carried out for horse, pig, cattle, sheep, and goat, but there is lack of information for asinine species. Consequently, the absence of ??label milk withdrawal time?? and MRLs in donkey??s milk indicates that IVM should not be used in lactating animals. On the contrary, information about IVM residues in milk would be of paramount importance in view of the fact that donkey??s milk is a suggested substitute for infants suffering from hypersensitivity to cow??s, sheep??s and goat??s milk protein or from multiple hypersensitivity. European legislation does not explicitly state that an MRL should be determined for every target species; however it??s interpretation led to MRLs being adopted for each species and each foodstuff. Although IVM is approved for use in all lactating animal species the possibility of an illegal use should be considered. In this paper, the problems arising from IVM administration in lactating donkey are analysed. A particular attention is paid for the existing legislation and some proposals are suggested for regulatory framework formulation. 相似文献
73.
Jos�� Luis Huertas Tal��n David Rodrigo Boria Luis Berges Muro Carmelo L��pez G��mez Jos�� Javier Mar��n Zurdo Francisco Valdivia Calvo Juan Jos�� Garde Barace 《The International Journal of Advanced Manufacturing Technology》2011,55(1-4):39-51
This paper offers a system for checking three or five axes high-speed machining centres by milling a sample sphere pattern. Using the right choice of toolpath, it is possible to check and compare the performance which the centre is capable of following. The main features under study here are ease of use and the great amount of information that can be drawn regarding high-speed machine performances, including the geometrical precision of the machine and tool setup for the chosen machining conditions. 相似文献
74.
Unmanned Aerial Vehicles (UAVs) are starting to be used for photogrammetric sensing of large areas in several application domains, such as agriculture, rescuing, and surveillance. In this context, the problem of finding a path that covers the entire area of interest is known as Coverage Path Planning (CPP). Although this problem has been addressed by several authors from a geometrical point of view, other issues such as energy, speed, acceleration, and image resolution are not often taken into account. To fill this gap, this paper first proposes an energy model derived from real measurements, and then uses this model to implement a coverage path planning algorithm for reducing energy consumption, as well as guaranteeing a desired image resolution. In addition, two safety mechanisms are presented: the first, executed off-line, checks whether the energy stored in the battery is sufficient to perform the planned path; the second, performed online, triggers a safe return-to-launch (RTL) operation when the actual available energy is equal to the energy required by the UAV to go back to the starting point. 相似文献
75.
Dourado EM Herdes C van Tassel PR Sarkisov L 《International journal of molecular sciences》2011,12(8):4781-4804
In this article we present a model for molecularly imprinted polymers, which considers both complexation processes in the pre-polymerization mixture and adsorption in the imprinted structures within a single consistent framework. As a case study we investigate MAA/EGDMA polymers imprinted with pyrazine and pyrimidine. A polymer imprinted with pyrazine shows substantial selectivity towards pyrazine over pyrimidine, thus exhibiting molecular recognition, whereas the pyrimidine imprinted structure shows no preferential adsorption of the template. Binding sites responsible for the molecular recognition of pyrazine involve one MAA molecule and one EGDMA molecule, forming associations with the two functional groups of the pyrazine molecule. Presence of these specific sites in the pyrazine imprinted system and lack of the analogous sites in the pyrimidine imprinted system is directly linked to the complexation processes in the pre-polymerization solution. These processes are quite different for pyrazine and pyrimidine as a result of both enthalpic and entropic effects. 相似文献
76.
Numerous experimental and naturalistic studies have shown the relevant role of ruminative styles in the onset, duration and severity of depressive episodes. Recent research has increasingly focused on the precursors of these ruminative responses. Neuroticism has been found to be closely related to ruminative styles, but the nature of this relationship is unknown. Across three studies, we explored the role of emotional overproduction, conceptualized as the tendency to simultaneously experience an elevated number of negative emotions and feelings during sad episodes. Study 1 showed that emotional overproduction is independently and strongly associated with ruminative styles. Furthermore, emotional overproduction was found to mediate the relationship between neuroticism and ruminative styles. Study 2 replicated these findings in a large community sample even after controlling for mood, personality, and other emotion-related variables. In Study 3, we conducted a laboratory study to increase the internal and external validity of our findings. Implications for personality, for coping and stress literature, and for clinical research and treatment are suggested. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
77.
Estrella Espada-Bellido Marta Ferreiro-González Gerardo F. Barbero Ceferino Carrera Miguel Palma Carmelo G. Barroso 《Food Analytical Methods》2018,11(9):2384-2395
Black mulberry (Morus nigra L.) is one of the most important species of the genus Morus as its fruit contains substantial levels of anthocyanins and phenolic compounds which show a potentially positive effect on the human health. Nowadays, PLE is becoming a promising extraction technology. Therefore, the development of fast extraction methods of anthocyanins and phenolic compounds from mulberry pulp using pressurized-liquid extraction (PLE) has been studied in this paper. The operating conditions (solvent, temperature, pressure, purge time, pH, and flushing) were investigated by a Box–Behnken design. Analysis of the model clearly showed that the most influential factors were temperature and solvent composition. The optimum extraction conditions for anthocyanins were 47.2% methanol in water, a temperature of 75.5 °C, pressure of 200 atm, a purge time of 90 s, pH 3.01, and 50.2% for flushing. The best conditions for the extraction of phenolics were 74.6% methanol, 99.4 °C, 100 atm, 90 s purge, pH 7, and 100% flushing. The optimum extraction time was 10 min. The precision values of the methods were also evaluated and excellent results (RSD?<?5%) were obtained. The developed methods were successfully applied to several mulberry marmalade samples. The results using PLE were compared to those achieved by UAE methods. Similar extraction yields were obtained for anthocyanins by PLE and UAE under optimized conditions; however, PLE required less methanol consumption. Besides, PLE showed higher extraction efficiency for total phenolic compounds. From the results, it can be concluded that pressurized-liquid extraction can be considered as an efficient alternative and powerful tool for the extraction of bioactive compounds from mulberries. 相似文献
78.
María Jesús Cejudo‐Bastante M. Carmen Rodríguez Dodero Enrique Durán Guerrero Remedios Castro Mejías Ramón Natera Marín Carmelo García Barroso 《Journal of the science of food and agriculture》2013,93(4):741-748
BACKGROUND: Despite the long history of sherry wine vinegar, new alternatives of consumption are being developed, with the aim of diversifying its market. Several new acetic‐based fruit juices have been developed by optimising the amount of sherry wine vinegar added to different fruit juices: apple, peach, orange and pineapple. Once the concentrations of wine vinegar were optimised by an expert panel, the aforementioned new acetic fruit juices were tasted by 86 consumers. Three different aspects were taken into account: habits of consumption of vinegar and fruit juices, gender and age. RESULTS: Based on the sensory analysis, 50 g kg?1 of wine vinegar was the optimal and preferred amount of wine vinegar added to the apple, orange and peach juices, whereas 10 g kg?1 was the favourite for the pineapple fruit. Based on the olfactory and gustatory impression, and ‘purchase intent’, the acetic beverages made from peach and pineapple juices were the most appreciated, followed by apple juice, while those obtained from orange juice were the least preferred by consumers. CONCLUSION: New opportunities for diversification of the oenological market could be possible as a result of the development of this type of new product which can be easily developed by any vinegar or fruit juice maker company. © 2012 Society of Chemical Industry 相似文献
79.
80.
Nicola Burriesci Carmelo Arcoraci PierLuigi Antonucci Giuseppe Polizzotti 《Materials Letters》1985,3(3):103-110
Pearlstones (perlite) from Sardinia (Italy). Milos (Greece) and Siberia (USSR) have been evaluated in terms of chemical composition, phase analysis, iron distribution, morphology and thermal properties, for application as raw material in zeolite synthesis. 相似文献