5,713 research outputs found
Dissipation function of the first-order phase transformation in VO2 ceramics by internal-friction measurements
In order to apply the concept of the dissipation function during the first-order phase transition (FOPT) in solids, we measured the internal friction Q-1 and shear modulus μ for a range of frequencies of polycrystalline ceramics VO2 as the sample passed through a FOPT across the temperature range of 300–420 K. The experiment was repeated for different temperature variation rate Ṫ. We have found that for each frequency, a maximum of Q-1 and a minimum of μ occurred at the same temperature Tp when Ṫ was kept constant. The numerical values of the dissipation function ΔGR plus other FOPT parameters have been deduced using Q-1 data. The general trend of ΔGR-T and other results are found to be consistent with known physical aspects.published_or_final_versio
Pelletizing analysis of cylinder pelletizer on MgO-fluxed pellets by discrete element method (DEM)
Discrete Element Method (DEM) was used to analyze palletization process of MgO-fluxed pellets in cylinder pelletizer. The effects of the charge ratio and rotational speed of the cylinder pelletizer on the behavior of MgO-fluxed pellets were investigated by using the simulation. The simulation results show that under the condition of a certain gradient angle of the cylinder pelletizer (The gradient angle is 3°), the suitable parameters of the cylinder pelletizer are that the charge ratio is 3 % and the rotational speed N/ critical rotational speed NC is 0,3
Quick and sensitive determination of gene expression of fatty acid synthase in vitro by using real-time polymerase chain reaction amplification (PCR)
Obesity results from an imbalance between energy intake and energy expenditure, which leads to a pathological accumulation of adipose tissue, but the underlying mechanism at gene level, is far from being elucidated. The objective of this study was to investigate the correlation between mRNA express from fatty acid synthase (FAS) with a different glucose level in primary adipocytes by real-time polymerase chain reaction amplification (PCR), which can aid in the understanding of the mechanism of obesity in vitro. By using the following formula, this study was able to quantify the mRNA expression of FAS of unknown samples: Y = -3.156X + 41.21 (Y = threshold cycle, X = log starting quantity). The high concentrations of glucose group significantly improved the mRNA expression of FAS (P < 0.01) rather than 0.25 and 0% concentrations of glucose. These results provide significant data that confirm an association between different glucose level and FAS expression in preadipocytes. The glucose concentration of the high group substantially augmented the mRNA expression of FAS.Key words: Expression, fatty acid synthase, lipid deposition, real-time polymerase chain reaction amplification (PCR)
A flicker-free electrolytic capacitor-less AC-DC LED driver
published_or_final_versio
Influence of silencing the MC4R gene by lentivirusmediated RNA interference in bovine fibroblast cells
Melanocortin receptor 4 (MC4R) is a key element in the mechanisms used to regulate both aspects of keeping the balance between energy uptake and energy expenditure. MC4R was knocked down by lentivirus-mediated shRNA expressing plasmids, which were controlled by the U6 promoter in bovine fibroblast cells, and the expression of MC4R was examined by the real time-PCR and Western blot analysis. Real time-PCR analysis was used to characterize the expression of Leptin, POMC, AGRP, MC3R and NPY gene. The relative genes [leptin, proopiomelanocortin (POMC), agouti-related peptide (AGRP), MC3R and neuropeptide Y (NPY)] expression level seemed to be closely associated with the MC4R gene in bovine fibroblast cell lines (BFCs). The levels of both MC4R mRNA and protein were significantly reduced by RNA interference (RNAi) mediated knockdown of MC4R in BFCs cells transfected with plasmid-based MC4R-specific shRNAs. The finding of this study demonstrated that vector based siRNA expression systems were an efficient approach to the knockdown of the MC4R gene expression in bovine fibroblast cells and they provided a new molecular basis for understanding the relationship of MC4R and other genes, which were responsible for the regulation of energy homeostasis by the melanocortin system.Key words: Melanocortin receptor 4 (MC4R), RNAi, bovine fibroblast cells, energy homeostasis
Reduction of the size of datasets by using evolutionary feature selection: the case of noise in a modern city
Smart city initiatives have emerged to mitigate the negative effects of a very fast growth of urban areas. Most of the population in our cities are exposed to high levels of noise that generate discomfort and different health problems. These issues may be mitigated by applying different smart cities solutions, some of them require high accurate noise information to provide the best quality of serve possible. In this study, we have designed a machine learning approach based on genetic algorithms to analyze noise data captured in the university campus. This method reduces the amount of data required to classify the noise by addressing a feature selection optimization problem. The experimental results have shown that our approach improved the accuracy in 20% (achieving an accuracy of 87% with a reduction of up to 85% on the original dataset).Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech.
This research has been partially funded by the Spanish MINECO and FEDER projects TIN2016-81766-REDT (http://cirti.es), and TIN2017-88213-R (http://6city.lcc.uma.es)
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