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101.
The presence or absence of filbertone in 21 admixtures of olive oil with virgin and refined hazelnut oils obtained using various processing techniques from different varieties and geographical origins was evaluated by solid phase microextraction and multidimensional gas chromatography (SPME–MDGC). The obtained results showed that the sensitivity achievable with the proposed procedure was enough to detect filbertone and, hence, to establish the adulteration of olive oil of different varieties with virgin hazelnut oils in percentages of up to 7%. The very low concentrations in which filbertone occurs in some refined hazelnut oils made difficult its detection in specific admixtures. In any case, the minimum adulteration level to be detected depends on the oil varieties present in the adulterated samples. In the present study, the presence of R- and S-enantiomers of filbertone could be occasionally detected in olive oils adulterated with 10–20% of refined hazelnut oil. 相似文献
102.
Kalyani?Dias Deland?J.?MyersEmail author Yilin?Bian Makuba?A.?Lihono Shaowen?Wu Patricia?A.?Murphy 《Journal of the American Oil Chemists' Society》2003,80(6):551-555
The functional properties of low- and high-M.W. (LMW and HMW, respectively) acidic subunits and the basic subunit separated
from the 11S soy protein fraction were studied and compared with the functional properties of the 11S fraction. Among the
functional properties investigated were solubility, emulsification, and viscosity. The results showed that the LMW acidic
subunit had higher solubility than the HMW acidic subunit. Among all the samples, the LMW subunit separated by using β-mercaptoethanol
(ME) was the most soluble, with a solubility of 98–100% at a pH of 6–12. The solubility profile of the HMW subunit followed
a pattern similar to the solubility of 11S. The lowest solubility was observed around pH values in the range close to the
isoelectric point for both the LMW and HMW subunit. The basic subunit was not soluble in the pH range 3–10; however, the solubility
increased more than 50% at pH 13 compared to the solubility at pH 10. The emulsification capacity of all subunits was higher
than 11S in the following descending order: LMW, basic, HMW, 11S. Emulsification activity and stability of the subunits were
greater than those of the 11S samples at room temperature and 95°C. With the exception of the LMW subunit separated with ME,
the subunits had a higher viscosity than 11S. The basic subunit separated with sodium bisulfite had the highest viscosity
of all the samples tested. 相似文献
103.
Potential process ‘hurdles’ in the use of macroalgae as feedstock for biofuel production in the British Isles 下载免费PDF全文
John J Milledge Patricia J Harvey 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2016,91(8):2221-2234
This review examines the potential technical and energy balance hurdles in the production of seaweed biofuel, and in particular for the MacroBioCrude processing pipeline for the sustainable manufacture of liquid hydrocarbon fuels from seaweed in the UK. The production of biofuel from seaweed is economically, energetically and technically challenging at scale. Any successful process appears to require both a method of preserving the seaweed for continuous feedstock availability and a method exploiting the entire biomass. Ensiling and gasification offer a potential solution to these two requirements. However there is need for more data particularly at a commercial scale. © 2016 The Authors. Journal of Chemical Technology & Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献
104.
The results of an experimental test program performed to investigate the influence of specimen dimensions and testing rate conditions on room temperature fracture toughness of PP homopolymer are presented. The material displayed nonlinear load‐displacement behavior and exhibited small amounts of slow crack growth (ductile tearing) prior to cleavage instability, which invalidates the direct application of the current standards for the determination of KIC in polymers. Data points were considerably scattered consistently with typical ductile‐brittle transition patterns. The resulting load‐displacement diagrams were analyzed in terms of KQ, KMAX, and the ratio PMAX/PQ. THe fracture toughness at instability, JC, was also computed and plotted against the amount of stable crack growth in order to construct J‐R curves as a function of size and strain rate. From these curves an alternative critical fracture parameter, KJIC, was calculated. Weibull statistics were used as a tentative approach for treating the scatter of fracture toughness of polypropylene homopolymer in large samples, which exhibited restricted ductile tearing. The significance of each of these methods and the validity and size independence of the corresponding parameters are discussed. 相似文献
105.
Shelley Waters Silvia Lee Ibnu Ariyanto Shay Leary Kylie Munyard Silvana Gaudieri Ashley Irish Richard J. N. Allcock Patricia Price 《International journal of molecular sciences》2022,23(21)
Around 80% of adults worldwide carry human cytomegaloviris (HCMV). The HCMV gene UL18 is a homolog of HLA class I genes and encodes a protein with high affinity for the NK and T-cell cytotoxicity inhibitor LIR-1. UL18 was deep sequenced from blood, saliva or urine from Indonesian people with HIV (PWH) (n = 28), Australian renal transplant recipients (RTR) (n = 21), healthy adults (n = 7) and neonates (n = 4). 95% of samples contained more than one variant of HCMV UL18, as defined by carriage of nonsynonymous variations. When aligned with immunological markers of the host’s burden of HCMV, the S318N variation associated with high levels of antibody reactive with HCMV lysate in PWH over 12 months on antiretroviral therapy. The A107T variation associated with HCMV antibody levels and inflammatory biomarkers in PWH at early timepoints. Variants D32G, D248N, V250A and E252D aligned with elevated HCMV antibody levels in RTR, while M191K, E196Q and F165L were associated with HCMV-reactive T-cells and proportions of Vδ2− γδ T-cells—populations linked with high burdens of HCMV. We conclude that UL18 is a highly variable gene, where variation may alter the persistent burden of HCMV and/or the host response to that burden. 相似文献
106.
Factors Influencing the Adhesion of Microorganisms to Surfaces 总被引:4,自引:0,他引:4
Brenda J. Little Patricia Wagner James S. Maki Marianne Walch Ralph Mitchell 《The Journal of Adhesion》1986,20(3):187-210
Starvation, growth phase, and carbon source influenced bacterial cell surface hydrophobicity. Both the number and kind of microorganisms that colonized metal surfaces depended on the type of metal and the presence of an imposed electrical potential. No significant differences in attachment and growth of a pure culture were observed when metal surfaces were dipped in an exogenous energy source. The chemical composition of naturally occurring adsorbed organic films on metal surfaces was shown to be independent of surface composition and polarization. 相似文献
107.
108.
Cecilia Arriagada Viviana A. Cavieres Charlotte Luchsinger Alexis E. Gonzlez Vanessa C. Muoz Jorge Cancino Patricia V. Burgos Gonzalo A. Mardones 《International journal of molecular sciences》2020,21(22)
Protein trafficking is altered when normal cells acquire a tumor phenotype. A key subcellular compartment in regulating protein trafficking is the Golgi apparatus, but its role in carcinogenesis is still not well defined. Golgi phosphoprotein 3 (GOLPH3), a peripheral membrane protein mostly localized at the trans-Golgi network, is overexpressed in several tumor types including glioblastoma multiforme (GBM), the most lethal primary brain tumor. Moreover, GOLPH3 is currently considered an oncoprotein, however its precise function in GBM is not fully understood. Here, we analyzed in T98G cells of GBM, which express high levels of epidermal growth factor receptor (EGFR), the effect of stable RNAi-mediated knockdown of GOLPH3. We found that silencing GOLPH3 caused a significant reduction in the proliferation of T98G cells and an unexpected increase in total EGFR levels, even at the cell surface, which was however less prone to ligand-induced autophosphorylation. Furthermore, silencing GOLPH3 decreased EGFR sialylation and fucosylation, which correlated with delayed ligand-induced EGFR downregulation and its accumulation at endo-lysosomal compartments. Finally, we found that EGF failed at promoting EGFR ubiquitylation when the levels of GOLPH3 were reduced. Altogether, our results show that GOLPH3 in T98G cells regulates the endocytic trafficking and activation of EGFR likely by affecting its extent of glycosylation and ubiquitylation. 相似文献
109.
Thandi Patricia Gumede 《乙烯基与添加剂工艺杂志》2021,27(3):469-484
This review paper deals with the overall crystallization behavior of polyethylene/wax blends as phase change materials (PCMs) for thermal energy storage with the determination of their thermal properties. The addition of molten wax to the polyethylenes decreases the crystallization and melting temperatures of the blends. However, incorporating fillers to the polyethylene/wax blends can either decrease or increase the crystallization and melting temperatures of the composites depending on the filler type. The normalized enthalpy values of linear low-density polyethylene showed no significant change when increasing the wax content. On the contrary, the normalized enthalpy values of the wax in the blends were lesser than that of pure wax and increased with increasing wax content. Since the wax in the blend had a lower crystallinity compared to pure wax, this influences its effectiveness as a PCM for thermal energy storage. The effect of different polyethylenes on the wax morphology gave rise to enhance phase separation when wax was blended to high-density polyethylene as compared to the other polyethylenes. On the contrary, the effect of various waxes on the morphology of polyethylene resulted in different morphologies due to the molecular weight of the wax used and the structure of the polyethylene chain. The addition of fillers to the polyethylene (PE)/wax samples resulted in enhanced phase separation. The overall isothermal crystallization rate and the equilibrium melting temperature of PEs in the PEs/wax blends were depressed by wax addition due to the wax dilution effect. 相似文献
110.
Patricia Seoane-Collazo Amparo Romero-Pic Eva Rial-Pensado Laura Liares-Pose nxela Estvez-Salguero Johan Fern Rubn Nogueiras Carlos Diguez Miguel Lpez 《International journal of molecular sciences》2021,22(4)
Several studies have reported that nicotine, the main bioactive component of tobacco, exerts a marked negative energy balance. Apart from its anorectic action, nicotine also modulates energy expenditure, by regulating brown adipose tissue (BAT) thermogenesis and white adipose tissue (WAT) browning. These effects are mainly controlled at the central level by modulation of hypothalamic neuropeptide systems and energy sensors, such as AMP-activated protein kinase (AMPK). In this study, we aimed to investigate the kappa opioid receptor (κOR)/dynorphin signaling in the modulation of nicotine’s effects on energy balance. We found that body weight loss after nicotine treatment is associated with a down-regulation of the κOR endogenous ligand dynorphin precursor and with a marked reduction in κOR signaling and the p70 S6 kinase/ribosomal protein S6 (S6K/rpS6) pathway in the lateral hypothalamic area (LHA). The inhibition of these pathways by nicotine was completely blunted in κOR deficient mice, after central pharmacological blockade of κOR, and in rodents where κOR was genetically knocked down specifically in the LHA. Moreover, κOR-mediated nicotine effects on body weight do not depend on orexin. These data unravel a new central regulatory pathway modulating nicotine’s effects on energy balance. 相似文献