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991.
Machine Learning - Online video games drive a multi-billion dollar industry dedicated to maintaining a competitive and enjoyable experience for players. Traditional cheat detection systems struggle... 相似文献
992.
993.
Karen C. A. Francisco Pedro F. Brandão Rui Miguel Ramos Luís Moreira Gonçalves Arnaldo A. Cardoso José António Rodrigues 《International Journal of Food Science & Technology》2020,55(1):248-258
Biogenic amines (BAs) are compounds present in foodstuff of animal origin that not only can be harmful to the consumer but can also serve as indicators of the product's edibility status. However, BAs’ analysis is rather complicated. Derivatisation methods have been employed to make their analysis less challenging. Salting-out assisted liquid–liquid extraction (SALLE) was herein applied to decrease time that the derivatising agent dansyl chloride (DNS-Cl) requires to be effective. DNS-Cl derivates were separated and analysed by high-performance liquid chromatography with UV and fluorescence detection (HPLC-UV/FD). It was by this way possible to analyse methylamine, dimethylamine, ethylamine, β-phenylethylamine, isopentylamine, putrescine, cadaverine, histamine, tyramine, spermidine and spermine in a straightforward manner in several fish-based and meat-based samples, obtaining results in the order of magnitude of about a few mg per kg. All calibrations curves had r2 higher than 0.99, and limits of detection ranged from 0.0075 to 1.6 mg L−1. 相似文献
994.
Camila Pereda Daniel G. Actis Pedro Mendoza Zélis Vera A. Alvarez Laura M. Sanchez 《应用聚合物科学杂志》2021,138(16):50261
Magnetic beads composed by polyvinyl alcohol and iron oxides were developed and fully characterized. The materials were not only cross-linked by a physical treatment but also the magnetic nanoparticles (MNPs) are acting as cross-linking dots. Interestingly, the analysis of scanning electron micrographs revealed that, in the case of hydrated samples, flower-like structures (average diameter 6–9 μm) being constituted by MNPs were present, whereas when the beads were dried the MNPs structure changed to porous spheres (average diameter 2–3 μm). Some of the prepared materials were tested to determine their capability to act as water remediation devices, and good removal results were obtained toward both methylene blue (average removal efficiency higher than 80%) and methyl orange (average removal efficiency lower than 30%) adsorption. The experiments performed confirmed that the adsorbent, once the treatment has ended, can be removed off through the simple employment of a permanent magnet. 相似文献
995.
Rosa Gabriela López GonzalezNúñez Roberto Carlos Vázquez-Fletes Pedro Ortega-Gudiño Milton Oswaldo Vázquez-Lepe Denis Rodrigue Rubén González-Núñez 《Polymer Engineering and Science》2021,61(4):1007-1017
In this work, rotational molding was used to produce parts based on a blend of linear low-density polyethylene (LLDPE) and polyamide 6 (PA6). In particular, the concentration of PA6 (0, 10, 20, and 30% vol) with and without a compatibilizer (Surlyn 9020) was investigated via two methods: dry blending in a high-shear mixer and melt compounding in a twin-screw extruder followed by pulverization. To determine the efficiency of the rotomolding process, similar parts were produced via compression molding. For rotational molding, dry ice (solid CO2) was used to create an inert atmosphere in the mold and the processing conditions were followed by the mold internal air temperature traces. From the samples produced, thermal, morphological, and mechanical properties were measured. The results showed that the rotomolded parts of the melt blended compounds generated smaller and better dispersed PA6 particles in the LLDPE matrix. This finer morphology led to improved mechanical properties, especially when the compatibilizer was present. But the latter was found to be more effective on the compression-molded samples. 相似文献
996.
Perdigão Pedro Lousã Pedro Ascenso João Pereira Fernando 《Multimedia Tools and Applications》2020,79(31-32):22131-22156
Multimedia Tools and Applications - Due to the increasing shortage of fish in the seas, Vessel Monitoring Systems (VMS) play a very important role in fishing activity monitoring, control and... 相似文献
997.
Bhargavi Mummareddy Michael Maravola Eric MacDonald Jason Walker Brian Hetzel Brett Conner Pedro Cortes 《International Journal of Applied Ceramic Technology》2020,17(2):413-423
In this work, metal-ceramic composite parts based on aluminum and alumina were manufactured in a two-stage process. First, silica was printed using a vat photopolymerization technique, followed by a curing and sintering stage, which resulted in ceramic precursors. Subsequently, these samples were subjected to a metal infiltration process to form interpenetrating metal-ceramic composites (IPCs). These composites have attracted considerable attention in the aerospace and defense sector due to the ductility associated to the metal phase and the strength offered by the ceramics. A novel application with utility includes composite tooling which requires a low coefficient of thermal expansion (CTE) for high temperatures. The investigated specimens were tested for surface quality and shrinkage, followed by a mechanical characterization. It was recorded that the samples presented a 12%–18% of shrinkage after the sintering process. The mechanical testing showed that the hardness, compression, and flexural strength of the composites were superior to the printed and sintered ceramics. A thermal analysis on the composite showed that its CTE is more than two times lower than the common composite tooling materials. It is expected that the present work can provide the foundations for further studies on these systems in the refractory, automotive, and armor-based fields. 相似文献
998.
Bruna Tereza Thomazini Zanella Isabele Cristina Magiore Bruno Oliveira Silva Duran Guilherme Gutierrez Pereira Igor Simes Tiagua Vicente Pedro Luiz Pucci Figueiredo Carvalho Rondinelle Artur Simes Salomo Edson Assuno Mareco Robson Francisco Carvalho Tassiana Gutierrez de Paula Margarida Maria Barros Maeli Dal-Pai-Silva 《International journal of molecular sciences》2021,22(6)
In fish, fasting leads to loss of muscle mass. This condition triggers oxidative stress, and therefore, antioxidants can be an alternative to muscle recovery. We investigated the effects of antioxidant ascorbic acid (AA) on the morphology, antioxidant enzyme activity, and gene expression in the skeletal muscle of pacu (Piaractus mesopotamicus) following fasting, using in vitro and in vivo strategies. Isolated muscle cells of the pacu were subjected to 72 h of nutrient restriction, followed by 24 h of incubation with nutrients or nutrients and AA (200 µM). Fish were fasted for 15 days, followed by 6 h and 15 and 30 days of refeeding with 100, 200, and 400 mg/kg of AA supplementation. AA addition increased cell diameter and the expression of anabolic and cell proliferation genes in vitro. In vivo, 400 mg/kg of AA increased anabolic and proliferative genes expression at 6 h of refeeding, the fiber diameter and the expression of genes related to cell proliferation at 15 days, and the expression of catabolic and oxidative metabolism genes at 30 days. Catalase activity remained low in the higher supplementation group. In conclusion, AA directly affected the isolated muscle cells, and the higher AA supplementation positively influenced muscle growth after fasting. 相似文献
999.
Cassio Eduardo Faria Sobue Felipe Schoemer Jardim Victor Claudio Bento Camargo Fabiane Leticia Lizarelli Pedro Carlos Oprime 《Quality and Reliability Engineering International》2020,36(5):1808-1819
To design the control chart, the in-control process mean and standard deviation must be estimated from historical samples, negatively affecting the chart's performance. The grand mean of a sample is the well-established estimator for the process mean. However, regarding the standard deviation, the chart's user has at least five different estimators available in the literature to choose from. In this paper, using intensive simulations, we study and compare the performance of the chart (under normality assumption and three-sigma limits) among the most five used standard deviation estimators. The unconditional in-control run length (RL0) is the most commonly used performance measure of a control chart, and many authors base their comparisons on the expectation of the RL0 or on the mean square error of the estimators. In contrast, we based our comparison on the proportions of the RL0 concentrated at some intervals that are usually considered undesired by the practitioner due to the high incidence of false alarms during the process monitoring (e.g., RL0 between 1 and 200), occurring earlier than expected when compared with known parameter situations. From our results, all the studied standard deviation estimators generate similar performances. However, even with this similarity, we showed that one of the most recommended standard deviation estimators in the literature in control charts with estimated parameters may be the most inappropriate choice based on the undesired RL0 proportions. 相似文献
1000.
Duarte Magalhães José Martins Frederico Branco Manuel Au-Yong-Oliveira Ramiro Gonçalves Fernando Moreira 《Expert Systems》2020,37(5):e12420
At a time when communication, new media, and digitalization are transversal to the whole of society, private health care organizations have the possibility of making their business processes evolve. The objective is thus to seize the benefits associated to the active use of patients' electronic health records (EHRs) as the basis for personalized health care. In order to initially validate the health care sector acceptance of a 360° health care information system (HIS), focused on collecting patients' data to create the necessary knowledge for delivering personalized health care procedures and initiatives, a focus group involving a set of health-related professionals was performed. Despite recognizing the immense possibilities associated to EHR and its direct incorporation on a 360° HIS, the referred professionals still highlighted their concerns relative to the maintenance of adequate security and privacy levels. With this in mind, a proposal for a 360° HIS model is presented, and its main functional blocks are described with a focus on triggering patient/customer loyalty. 相似文献