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151.
152.
Jose Sanchez-Collado Isaac Jardin Jose J. Lpez Victor Ronco Gines M. Salido Charlotte Dubois Natalia Prevarskaya Juan A. Rosado 《International journal of molecular sciences》2021,22(21)
The mammalian exclusive Orai3 channel participates in the generation and/or modulation of two independent Ca2+ currents, the store-operated current, Icrac, involving functional interactions between the stromal interaction molecules (STIM), STIM1/STIM2, and Orai1/Orai2/Orai3, as well as the store-independent arachidonic acid (AA) (or leukotriene C4)-regulated current Iarc, which involves Orai1, Orai3 and STIM1. Overexpression of functional Orai3 has been described in different neoplastic cells and cancer tissue samples as compared to non-tumor cells or normal adjacent tissue. In these cells, Orai3 exhibits a cell-specific relevance in Ca2+ influx. In estrogen receptor-positive breast cancer cells and non-small cell lung cancer (NSCLC) cells store-operated Ca2+ entry (SOCE) is strongly dependent on Orai3 expression while in colorectal cancer and pancreatic adenocarcinoma cells Orai3 predominantly modulates SOCE. On the other hand, in prostate cancer cells Orai3 expression has been associated with the formation of Orai1/Orai3 heteromeric channels regulated by AA and reduction in SOCE, thus leading to enhanced proliferation. Orai3 overexpression is associated with supporting several cancer hallmarks, including cell cycle progression, proliferation, migration, and apoptosis resistance. This review summarizes the current knowledge concerning the functional role of Orai3 in the pathogenesis of cancer. 相似文献
153.
The effects of time and temperature on the alcoholysis of rubber seed, melon seed, linseed, and soyabean oils have been studied. The following temperatures were investigated: 200, 220, 245, and 260°C. Litharge (PbO) was used as the alcoholysis catalyst. The optimum alcoholysis temperature was found to be 245 ± 2 °C for each of the oils. At lower alcoholysis temperatures (<245°C), there is the preferential alcoholysis of seed oils derived from unsaturated acid; and the general alcoholysis rates were found to be in the following order: linseed oil ≈ rubber seed oil ≥ soyabean oil ≈ melon seed oil. The alcohol‐solubility of the oils is generally observed to begin at 42–45% conversion of oils to monoglycerides. The α‐monoglyceride contents of the alcoholysis mixtures of rubber seed and linseed oils were generally similar at methanol tolerance, and higher than those of melon seed and soyabean oils. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 1826–1832, 2000 相似文献
154.
In control practice, one of the fundamental limitations of feedback is given by the sensor noise effect. This problem is still more important in uncertain nonlinear control systems. This work extends the previous multi‐loop QFT technique, specifically designed to accommodate bandwidth limitation, to the nonlinear case. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
155.
The Neugebauer equations and the Demichel equations on which they are based are one of the basic tools for modeling colour printing systems that use the halftoning technique. However, these equations implicitly assume that the colour ink distributions in the screen superposition are statistically independent. We show that this condition is not satisfied in the conventional screen superposition used for colour printing, and we discuss the consequences of this fact. Furthermore, we give a precise criterion that determines, for any number of superposed regular screens, in which cases the Demichel (and hence the Neugebauer) equations are satisfied, and in which cases they fail: The Demichel equations fail in all cases where the screen superposition is singular, and they are satisfied in all nonsingular screen superpositions. We illustrate our results with several examples of both cases. © 2000 John Wiley & Sons, Inc. Col Res Appl, 25, 267–277, 2000 相似文献
156.
Zinian Wang Marilyn L. Kwan Reina Haque Prashant K. Singh Maciej Goniewicz Rachel Pratt Valerie S. Lee Janise M. Roh Isaac J. Ergas Kimberly L. Cannavale Ronald K. Loo David S. Aaronson Charles P. Quesenberry Yuesheng Zhang Christine B. Ambrosone Lawrence H. Kushi Li Tang 《Molecular nutrition & food research》2024,68(8):2400087
157.
João Paulo Melo Silva Augusta Cerceau Isaac 《Mineral Processing and Extractive Metallurgy Review》2018,39(1):68-72
Cationic reverse flotation of quartz is the standard or reference concentration route for itabirites containing at least 45% iron. Preceding the flotation stage, desliming in hydrocyclones must be conducted to remove ultrafine and colloidal particles from the flotation feed. The flotation performance assessed by weight and metallurgical recoveries and silica contamination in the concentrate is impaired by lower iron feed grades. Exploratory experiments of magnetic separation indicated that iron oxide particles in the size range <37 µm are entrained toward the non-magnetic product. This finding suggested a campaign of testing an alternative circuit consisting of magnetic separation preceding reverse flotation. Magnetic separation plays the roles of desliming and pre-concentration. The achieved content of silica in the alternative route concentrate was 1.46%, meeting the market specification for blast furnace pellet of 2%. The alternative route yielded significant gains in weight and metallurgical recoveries, reaching values 3.3% and 4.4% higher, respectively. 相似文献
158.
Globally, postharvest loss reduction has been emphasized as an effective option for improving food security and environmental sustainability. Yam production in the Zabzugu district of Northern Ghana suffers from high postharvest losses, with varying degrees of economic, social and environmental implications. Improving the welfare of farmers through postharvest loss reduction requires farmers’ effective management of the losses. The purpose of this study is to examine how effectively farmers manage postharvest losses and the rewards derived from such efforts. Using a cross-section of 201 randomly selected yam farmers from major production communities in the Zabzugu district of Northern Ghana, we applied a simultaneous equation modelling approach to examine the contemporaneous correlation between postharvest loss management and income. Results provided evidence that good postharvest loss management improves welfare of yam farmers through increased income earnings and vice versa, especially for those who produce for commercial purposes. On the other hand, subsistence farmers were better at managing postharvest losses, though with lower monetary rewards. The policy implications are that interventions should target farmer education and training to improve the skills of farmers in managing postharvest losses. 相似文献
159.
A predictive model to correlate fuel specifications with on-road vehicles emissions in Mexico 总被引:1,自引:0,他引:1
Mexico is currently in the process of implementing its third air management program, which includes control measures targeting emissions reductions from mobile, point, and area sources. Achieving the program goals will require changes in the composition and in physical properties of gasoline and implementing an emissions reduction schedule. For that purpose a study was undertaken to support understanding of the effect of gasoline fuel parameters on exhaust emissions. Specifically, the relative impacts of Reid vapor pressure, distillation parameters, oxygen, sulfur, olefins, and aromatic contents on the exhaust emissions of in-use vehicles of the metropolitan area of Mexico City were investigated. The results were used to develop a model to predict CO, nitrogen oxides, total hydrocarbons, and toxic emissions such as benzene, 1,3-butadiene, formaldehyde, and acetaldehyde. Also a statistical model that predicts evaporative emissions was built. Results of the present model are compared with those obtained using the complex model of the United States Environmental Protection Agency. 相似文献
160.
González-Mariño I Quintana JB Rodríguez I González-Díez M Cela R 《Analytical chemistry》2012,84(3):1708-1717
For the first time, a mixed-mode solid-phase extraction with fractionation of basic analytes from neutral and acidic species during cartridge elution and liquid chromatography-quadrupole-time-of-flight mass spectrometry (LC-QTOF-MS) was combined for the quantitative determination of 24 illicit drugs and metabolites in urban sewage samples. The effects of several sample preparation and instrumental parameters in the sensitivity and selectivity of the quantitative method are thoroughly discussed. Under final working conditions, recoveries above 63% and 82% were attained for all species in raw and treated sewage, respectively; whereas, the limits of quantification of the method, defined for a signal-to-noise of 10 (S/N = 10), ranged from 2 to 50 ng L(-1). Sequential elution of mixed-mode cartridges allowed a significant reduction of matrix effects observed during electrospray ionization of basic drugs versus those measured for hydrophilic balance reversed-phase sorbents and the same mixed-mode polymer without fractionated elution. Analysis of raw wastewater samples confirmed the ubiquity of cocaine (COC), benzoylecgonine (BE), and 11-nor-9-carboxy-Δ(9)-tetrahydrocannabinol (THCCOOH) in this matrix. The capability of the above methodology to identify new illicit drugs and/or metabolites in sewage samples is also discussed. With this aim, a two step strategy is proposed. First, high-resolution MS chromatograms, acquired throughout each chromatographic run, are automatically searched against an in-house built database, a reduced list of candidate drugs is generated, and the corresponding extracted ion chromatograms are obtained. In a further LC run, the tandem mass spectrometry (MS/MS) spectra of unknown peaks are acquired using different collision energies and compared with those existing in public libraries, or interpreted, to assign the unknown peak to one of the previously selected candidates. 相似文献