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91.
Saga LC Rukke EO Liland KH Kirkhus B Egelandsdal B Karlsen J Volden J 《Journal of the American Oil Chemists' Society》2011,88(12):1883-1895
The oxidative stability of mixtures of edible oils containing polyunsaturated fatty acids (PUFA) and microcrystalline cellulose
(MCC) was investigated. The mixtures studied consisted of oils of either camelina (CAM), cod liver (CLO), or salmon (SO) mixed
with either colloidal or powdered MCC. A 50:50 (w/w) ratio of oil:MCC resulted in an applicable mixture containing high levels
of PUFA edible oil and dietary fiber. The oxidative stability of the formulated mixtures and the pure oils was investigated
over a period of 28 days. The peroxide value (PV) was assessed as a parameter for primary oxidation products and dynamic headspace
gas chromatography mass spectrometry (GC/MS) was used to analyze secondary volatile organic compounds (VOC). CAM and the respective
mixtures were oxidatively stable at both 4 and 22 °C during the storage period. The marine oils and the respective mixtures
were stable at 4 °C. At 22 °C, an increase in hydroperoxides was found, but no increase in VOC was detected during the time-frame
investigated. At 42 °C, prominent increases in PV and VOC were found for all oils and mixtures. Hexanal, a common marker for
the degradation of n-6 fatty acids, propanal and 2,4-heptadienal (E,E), common indicators for the degradation of n-3 fatty acids, were among the volatiles detected in the headspace of oils and mixtures. This study showed that a mixture
containing a 50:50 ratio of oil:MCC can be obtained by a low-tech procedure that does not induce oxidation when stored at
low temperatures during a period of 1 month. 相似文献
92.
Phage display with filamentous phages is widely applied and well developed, yet proteins requiring a cytoplasmic environment for correct folding still defy attempts at functional display. To extend applicability of phage display, we employed the twin-arginine translocation (TAT) pathway to incorporate proteins fused to the C-terminal domain of the geneIII protein into phage particles. We investigated functionality and display level of fluorescent proteins depending on the translocation pathway, which was the TAT, general secretory (SEC) or signal recognition particle (SRP) pathway mediated by the TorA, PelB or DsbA signal sequences, respectively. Importantly, for green fluorescent protein, yellow fluorescent protein and cyan fluorescent protein, only TAT, but not SEC or SRP, translocation led to fluorescence of purified phage particles, although all three proteins could be displayed regardless of the translocation pathway. In contrast, the monomeric red fluorescent protein mCherry was functionally displayed regardless of the translocation pathway. Hence, correct folding and fluorophor formation of mCherry is not limited to the cytosol. Furthermore, we successfully displayed firefly luciferase as well as an 83 kDa argonaute protein, both containing free cysteines. This demonstrates broad applicability of the TAT-mediated phagemid system for the display of proteins requiring cytoplasmic factors for correct folding and should prove useful for the display of proteins requiring incorporation of co-factors or oligomerization to gain function. 相似文献
93.
Farnaz Adib Yaghmaie Kristian Hengster Movric Frank L. Lewis Rong Su 《国际强度与非线性控制杂志
》2019,29(10):2995-3013
》2019,29(10):2995-3013
Differential graphical games have been introduced in the literature to solve state synchronization problem for linear homogeneous agents. When the agents are heterogeneous, the previous notion of graphical games cannot be used anymore and a new definition is required. In this paper, we define a novel concept of differential graphical games for linear heterogeneous agents subject to external unmodeled disturbances, which contain the previously introduced graphical game for homogeneous agents as a special case. Using our new formulation, we can solve both the output regulation and H∞ output regulation problems. Our graphical game framework yields coupled Hamilton‐Jacobi‐Bellman equations, which are, in general, impossible to solve analytically. Therefore, we propose a new actor‐critic algorithm to solve these coupled equations numerically in real time. Moreover, we find an explicit upper bound for the overall ‐gain of the output synchronization error with respect to disturbance. We demonstrate our developments by a simulation example. 相似文献
94.
95.
Dr. Maria Teresa Borrello Dr. Hanae Benelkebir Adam Lee Chak Hin Tam Manar Shafat Dr. Stuart A. Rushworth Prof. Kristian M. Bowles Leon Douglas Dr. Patrick J. Duriez Dr. Sarah Bailey Prof. Simon J. Crabb Prof. Graham Packham Prof. A. Ganesan 《ChemMedChem》2021,16(8):1316-1324
Lysine-specific demethylase 1 (LSD1/KDM1A) oxidatively removes methyl groups from histone proteins, and its aberrant activity has been correlated with cancers including acute myeloid leukemia (AML). We report a novel series of tranylcypromine analogues with a carboxamide at the 4-position of the aryl ring. These compounds, such as 5 a and 5 b with benzyl and phenethylamide substituents, respectively, had potent sub-micromolar IC50 values for the inhibition of LSD1 as well as cell proliferation in a panel of AML cell lines. The dose-dependent increase in cellular expression levels of H3K4me2, CD86, CD11b and CD14 supported a mechanism involving LSD1 inhibition. The tert-butyl and ethyl carbamate derivatives of these tranylcypromines, although inactive in LSD1 inhibition, were of similar potency in cell-based assays with a more rapid onset of action. This suggests that carbamates can act as metabolically labile tranylcypromine prodrugs with superior pharmacokinetics. 相似文献
96.
Yohanes C. Malede Julien P. Simon Torbjrn Jonsson Melanie Montgomery Kristian V. Dahl John Hald 《工业材料与腐蚀》2019,70(8):1486-1506
Ni–(35–45)Cr–4Nb alloys containing different fractions of α‐Cr were exposed to potassium chloride (KCl)‐induced corrosion. The corrosion exposures were carried out for 168 hr at 600°C in a 15% (vol/vol) H2O (g) + 5% (vol/vol) O2 (g) + N2 (g; balance) atmosphere using KCl‐free (reference) and predeposited KCl samples. To mimic the KCl deposition in real boilers, 24 hr exposures where KCl vapor condensed continuously onto samples were also performed. The corrosion attack of the studied materials increased significantly when KCl was present compared to the KCl‐free samples. For the KCl exposures, the corrosion attack drastically increased when a significant α‐Cr fraction was present. α‐Cr was either selectively attacked or dissolved through solid‐state diffusion and a layered build‐up of the outer external scale of K2CrO4 and chromia could be observed. For the in situ condensed KCl exposure, severe corrosion was observed already within the 24 hr exposure, indicating a higher corrosion rate compared with when KCl was predeposited. 相似文献
97.
The relationship between the norm square of the standardized cumulative distribution and the chi-square statistic is examined using the form of the covariance matrix as well as the projection perspective. This investigation enables us to give uncorrelated components of the chi-square statistic and to provide interpretation of these components as innovations standardizing the cumulative distribution values. The norm square of the standardized difference between empirical and theoretical cumulative distributions is also examined as an objective function for parameter estimation. Its relationship to the chi-square distance enables us to discuss the large sample properties of these estimators and a difference in their properties in the cases that the distribution is evaluated at fixed and random points. 相似文献
98.
Christian Heubner Sebastian Maletti Henry Auer Juliane Hüttl Karsten Voigt Oliver Lohrberg Kristian Nikolowski Mareike Partsch Alexander Michaelis 《Advanced functional materials》2021,31(51):2106608
The development of rechargeable batteries with high-energy density is critical for future decarbonization of transportation. Anode-free Li-ion batteries, using a bare current collector at the anode side without any excess of Li, provide the highest volumetric energy density ( > 1500 Wh L−1) among all possible cell configurations. Furthermore, elimination of the anode material coating reduces material consumption and greatly simplifies cell production, which in turn lowers costs. Although significant progress has been made recently by the application of modified current collectors, optimized cycling parameters and improved liquid electrolytes, insufficient efficiencies, and dendritic growth during lithium plating lead to poor cycle life of typically less than 100 cycles as well as safety issues. Alternatively, very recent studies have demonstrated anode-free solid-state batteries that combine the benefits of high energy anode-free cell configuration and solid-state systems with high safety, exceeding 1000 cycles. This review provides an overview of recent developments toward anode-free solid-state batteries and highlights the current issues and challenges in this nascent field. It is concluded that, although major challenges remain at the present, the lessons learned in the fields of liquid electrolytes and solid-state lithium metal batteries can accelerate the development of anode-free solid-state batteries of practical relevance. 相似文献
99.
Jesús Rodríguez-Sánchez Barbara Myszka Aldo Roberto Boccaccini Dag Kristian Dysthe 《Journal of the American Ceramic Society》2019,102(11):6980-6990
Calcium carbonate cements have emerged in the last few years as an attractive candidate for biomedical applications. They can be easily prepared by mixing water with two metastable calcium carbonate phases––amorphous calcium carbonate (ACC) and vaterite––which (re)crystallize into calcite during setting reaction. The transformation kinetics (and therefore the final surface cement composition) strongly depends on the initial mixture design and is controlled by the dissolution of ACC, whereas calcite nucleation typically controls their recrystallization in fluid batch experiments. Novel compositions are presented in this paper by incorporating organic molecules as a proxy to test their capability to carry on other biomolecules like proteins or antibiotics. The hardened samples are microporous and show excellent bioactivity rates, although their mechanical properties still remain poor. However, this would not be a handicap for in-vivo applications such as bone filling, especially in low mechanical stress locations. 相似文献
100.
Economics of fixed broadband access network strategies 总被引:2,自引:0,他引:2
Monath T. Kristian N. Cadro P. Katsianis D. Varoutas D. 《Communications Magazine, IEEE》2003,41(9):132-139
This article presents a comprehensive techno-economic evaluation of two upgrade strategy cases for broadband IP services for residential and business customers, and illustrates their respective merits and pitfalls, allowing the definition of a reasonable investment policy. The work should enable establishment of guidelines for broadband infrastructure upgrade strategies from the incumbent operator's view. Following the definition of appropriate service sets, and taking into account demand scenarios established within the project, this work has been focused on developing a techno-economic model, based on the TONIC tool. Tariff structures have been applied to compute the key economic indicators, net present value, internal rate of return, and payback period. This investment analysis was carried using the tool, which was developed by IST-TONIC. The results show that the choice of technology (Ethernet or ATM) has almost no effect on the cost level and profitability of the cases. For the suburban area, a fiber to the cabinet solution is too expensive due to heavy infrastructure investments; for dense urban and urban areas the FTTC solution is worth the investments. The FTTH/office deployment scenario is only profitable in dense urban areas (>5000 potential customers/km/sup 2/) and already highly risky in the urban area. 相似文献