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31.
Coenzyme Q10 (CoQ10) is a strongly hydrophobic lipid that functions in the electron transport chain and as an antioxidant. CoQ10 was conferred with aqueous solubility by incorporation into nanoparticles containing phosphatidylcholine (PtdCho) and apolipoprotein (apo) A-I. These particles, termed CoQ10 nanodisks (ND), contain 1.0 mg CoQ10/5 mg PtdCho/2 mg apoA-I (97% CoQ10 solubilization efficiency). UV/Vis absorbance spectroscopy of CoQ10 ND revealed a characteristic absorbance peak centered at 275 nm. Incorporation of CoQ10 into ND resulted in quenching of apoA-I tryptophan fluorescence emission. Gel filtration chromatography of CoQ10 ND gave rise to a single major absorbance peak and HPLC of material extracted from this peak confirmed the presence of CoQ10. Incubation of cultured cells with CoQ10 ND, but not empty ND, resulted in a significant increase in the CoQ10 content of mitochondria as well as enhanced oxidative phosphorylation, as observed by a ~24% increase in maximal oxygen consumption rate. Collectively, a facile method to solubilize significant quantities of CoQ10 in lipid nanoparticles has been developed. The availability of CoQ10 ND provides a novel means to investigate biochemical aspects of CoQ10 uptake by cells and/or administer it to subjects deficient in this key lipid as a result of inborn errors of metabolism, statin therapy, or otherwise.  相似文献   
32.
The nuclear retinoic acid receptor‐related orphan receptor γ (RORγ; NR1F3) is a key regulator of inflammatory gene programs involved in T helper 17 (TH17) cell proliferation. As such, synthetic small‐molecule repressors (inverse agonists) targeting RORγ have been extensively studied for their potential as therapeutic agents for various autoimmune diseases. Alternatively, enhancing TH17 cell proliferation through activation (agonism) of RORγ may boost an immune response, thereby offering a potentially new approach in cancer immunotherapy. Herein we describe the development of N‐arylsulfonyl indolines as RORγ agonists. Structure–activity studies reveal a critical linker region in these molecules as the major determinant for agonism. Hydrogen/deuterium exchange coupled to mass spectrometry (HDX‐MS) analysis of RORγ–ligand complexes help rationalize the observed results.  相似文献   
33.
A single chain Fv antibody–streptavidin fusion proteinwas expressed and purified from bacterial inclusion bodies followingcloning of the genes encoding the variable region of the heavychain and light chain of the murine OX26 monoclonal antibodyto the rat transferrin receptor. The latter undergoes receptormediated transcytosis through the brain capillary endothelialwall in vivo, which makes up the blood–brain barrier (BBB);therefore, the OX26 monoclonal antibody and its single chainFv analog may act as brain drug delivery vectors in vivo. Attachmentof biotinylated drugs to the antibody vector is facilitatedby production of the streptavidin fusion protein. The bi-functionalityof the OX26 single chain Fv antibody–streptavidin fusionprotein was retained, as the product both bound biotin and therat transferrin receptor in vitro and in vivo, based on pharmacokineticand brain uptake analyses in anesthetized rats. The attachmentof biotin–polyethyleneglycol–fluorescein to theOX26 single chain Fv antibody–streptavidin fusion proteinresulted in illumination of isolated rat brain capillaries inconfocal fluorescent microscopy. In conclusion, these studiesdemonstrate that genetically engineered single chain Fv antibody–streptavidinfusion proteins may be used for non-invasive neurotherapeuticdelivery to the brain using endogenous BBB transport systemssuch as the transferrin receptor.  相似文献   
34.
A tool for the generation of decomposition schemes of large molecules has been developed. These decomposition schemes contain radicals which can be eliminated from the model equations if both the μ‐hypothesis and the pseudosteady‐state approximation are valid. The reaction rate coefficients and thermodynamic parameters have been calculated by incorporating a comprehensive group additive framework. A microkinetic model for the pyrolysis of methyl esters with a carbon number of up to 19 has been generated using this tool. It is validated by comparing calculated and experimental yields of the pyrolysis of methyl decanoate and novel rapeseed methyl ester pyrolysis data in the temperature range from 800 to 1100 K and methyl ester partial pressure range from 1 × 10?3 to 1 × 10?2 MPa. This modeling frame work allows to not only assess the use of methyl ester mixtures as potential feedstock for olefin production but also their effect as blend‐in or trace impurity. © 2015 American Institute of Chemical Engineers AIChE J, 61: 4309–4322, 2015  相似文献   
35.
Supplementary cementitious materials (SCMs) are widely used to partially replace portland clinker in blended cements. Reducing clinker contents further without compromising the development of early strength necessitates a better assessment and enhancement of the reactivity of the available SCMs. To this purpose, the reactivity of synthesized calcium aluminosilicate glasses covering a compositional range from blast‐furnace slags (BFS) over fly ashes to silica fume was analyzed by dissolution experiments. Initial glass dissolution rates were measured at 20°C and pH 13, and with varying initial concentrations of aqueous Al, Ca, and Si. At pH 13, glass dissolution rates were observed to scale linearly with the glass Ca/(Al + Si) molar ratio. Ca‐rich blast‐furnace type glass dissolution was shown to be up to one order of magnitude faster than tectosilicate fly ash and silica fume type glass dissolution, supporting different pathways to dissolution. In solutions that are strongly undersaturated with respect to hydrous glass and hydration products, glass dissolution rates are independent of changes in solution undersaturation and aqueous Si activity. In contrast, dissolution rates decrease with aqueous Ca concentration for all glasses and with aqueous Al concentration for tectosilicate‐type glasses. The insights gained are instrumental in finding ways to enhance SCM reactivity.  相似文献   
36.
This article describes three generic models and application methods that can be used to analyze temperature development in an electronic product during conceptual design. The models are based on generally known heat transfer and resistor–capacitor network theory and are theoretically and numerically approximated. The result is three easy-to-use tools for conceptual thermal design. Application of the models in design practice has been assessed using a usability experiment and several in-depth interviews with industrial design engineers from the field.  相似文献   
37.
38.
Image acquisition technology is improving very fast from a performance point of view. However, there are physical restrictions that can only be solved using software processing strategies. This is particularly true in the case of super resolution (SR) methodologies. SR techniques have found a fertile application field in airborne and space optical acquisition platforms. Single-frame SR methods may be advantageous for some remote-sensing platforms and acquisition time conditions. The contributions of this article are basically two: (1) to present an overview of single-frame SR methods, making a comparative analysis of their performance in different and challenging remote-sensing scenarios, and (2) to propose a new single-frame SR taxonomy, and a common validation strategy. Finally, we should emphasize that, on the one hand, this is the first time, to the best of our knowledge, that such a review and analysis of single SR methods is made in the framework of remote sensing, and, on the other hand, that the new single-frame SR taxonomy is aimed at shedding some light when classifying some types of single-frame SR methods.  相似文献   
39.
In order to perform data reconciliation, it is important that noises in the data have well-defined distributions. The motivation behind this study was to enable the comparison between a discrete and continuous data set so that means can be compared for gross error over the short term; this required that local variables exhibit similar distributions.A case study was done on a system where non-continuum loads from a dump truck were to be reconciled with two downstream continuum weightometers. An algorithm was developed using the binomial distribution and time delay in order to simulate the effect of the dump pocket.Regression analysis based on principal components was used to evaluate the performance of the smoothing algorithm and to determine the most likely maximum hopper capacity that locates between the two weightometers.  相似文献   
40.
This study reports on the development and validation of measurement scales to study the different roles fulfilled by ICT coordinators. Based on a review of the literature, a 24 item questionnaire was constructed and administered to a sample of 177 Flemish ICT coordinators working in primary education. Exploratory factor analysis revealed a four-factor solution: the ICT coordinator as a planner, a budgeter, a technician, and an educationalist. Qualitative data corroborated these roles. This study provides a quantitative measure of the different roles assumed by ICT coordinators in practice. The implications of our findings for schools, researchers and policy makers are discussed.  相似文献   
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