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541.
Boettler U Volz N Pahlke G Teller N Kotyczka C Somoza V Stiebitz H Bytof G Lantz I Lang R Hofmann T Marko D 《Molecular nutrition & food research》2011,55(5):798-802
Recently, the coffee constituents 5-O-caffeoylquinic acid (CGA) and N-methylpyridinium (NMP) were identified as inducers of the Nrf2/antioxidant-response element (ARE) detoxifying pathway under cell-culture condition. To study the impact of CGA and NMP on the Nrf2-activating properties of a complex coffee beverage, two different model coffees were generated by variation of the roasting conditions: a low-roast coffee rich in CGA and a heavy-roast low in CGA but containing high levels of NMP. Activation of the Nrf2/antioxidant-response element pathway was monitored in vitro and in vivo. 相似文献
542.
During ripening, body colour of Emmental cheeses was evaluated by tristimulus reflectance measurements. Tristimulus primaries were transformed to the Helmholtz system and into CIELAB-coordinates in order to obtain interpretable results. Apart from lightness decreasing with increasing maturation time, it was found by using both systems that, (1) colourfulness increased continuously up to a cheese age of approximately 10 weeks and then remained constant, and (2) the hue of the cheese body shifted towards a slightly more orange colour in the last stage of ripening. The yellowness index, which represents a one-dimensional measure calculated from tristimulus primaries, is proposed as a simple and adequate measure of cheese body colour, and interrelations with CIELAB-values commonly used in food science are outlined. 相似文献
543.
Stephan Breitkreutz Josef Kiermaier Cenk Yilmaz Xueming Ju Gy?rgy Csaba Doris Schmitt-Landsiedel Markus Becherer 《Journal of Computational Electronics》2011,10(4):352-359
In this paper we investigate error rates of nanomagnetic logic devices with perpendicular magnetization by compact modeling.
Two different types of nanomagnets for information propagation and logic computing are introduced. The switching behavior
of field-coupled nanomagnets is measured and analyzed. A compact model is derived from physics and experimental results are
applied to the magnetic compact model. General requirements for fabrication parameters and clocking fields for reliable operation
are extracted. We perform simulations and measurements on single devices to demonstrate the accuracy of the macromodel. Simulations
on complex systems show that the error rate of a field-coupled magnetic system strongly depends on the variation of the switching
field and the strength of the coupling field between the nanomagnets. The error rate of a 1-bit full adder is investigated
for varying dot parameters. The results demonstrate the importance of fast simulation tools for investigations on the design
of nanomagnetic computing devices and systems. 相似文献
544.
The effect of cranberry juice (CJ) and cranberry proanthocyanidins (PAC) on the infectivity of human enteric virus surrogates, murine norovirus (MNV-1), feline calicivirus (FCV-F9), MS2(ssRNA) bacteriophage, and phiX-174(ssDNA) bacteriophage was studied. Viruses at high (∼7 log10 PFU/ml) or low (∼5 log10 PFU/ml) titers were mixed with equal volumes of CJ, 0.30, 0.60, and 1.20 mg/ml final PAC concentration, or water and incubated for 1 h at room temperature. Viral infectivity after treatments was evaluated using standardized plaque assays. At low viral titers, FCV-F9 was undetectable after exposure to CJ or the three tested PAC solutions. MNV-1 was reduced by 2.06 log10 PFU/ml with CJ, and 2.63, 2.75, and 2.95 log10 PFU/ml with 0.15, 0.30, and 0.60 mg/ml PAC, respectively. MS2 titers were reduced by 1.14 log10 PFU/ml with CJ, and 0.55, 0.80, and 0.96 log10 PFU/ml with 0.15, 0.30, and 0.60 mg/ml PAC, respectively. ?-X174 titers were reduced by 1.79 log10 PFU/ml with CJ, and 1.95, 3.67, and 4.98 log10 PFU/ml with PAC at 0.15, 0.30, and 0.60 mg/ml, respectively. Experiments using high titers showed similar trends but with decreased effects. CJ and PAC show promise as natural anti-virals that could potentially be exploited for foodborne viral illness treatment and prevention. 相似文献
545.
The phase behavior of the binary system consisting of isotactic polypropylene (i-PP) and N,N′,N″-tris-isopentyl-1,3,5-benzene-tricarboxamide (1)—a selected member of a class of novel, versatile ‘designer’ nucleating/clarifying agents—was investigated over the entire additive concentration range by means of differential scanning calorimetry (DSC) and optical microscopy. Experimental phase diagrams were constructed from data obtained in melting and crystallization studies, and a simple monotectic is advanced, very similar to the previously studied binary system i-PP/1,3:2,4-bis(3,4-dimethylbenzylidene) sorbitol (DMDBS). In contrast to the latter, the crystallization temperature in the present system i-PP/1 was found to increase to ∼120 °C already at the lowest additive concentration employed and remained constant at further increasing additive concentration. Liquid-liquid phase separation was observed at elevated temperatures for i-PP/1 mixtures comprising more than ∼2 wt% of 1. A study on the optical properties of the i-PP/1 system revealed that the values for haze and clarity of injection-molded plaques progressively decreased and increased, respectively, in the concentration range up to 0.15 wt%. An intermediate region of fairly concentration-independent optical properties was found between 0.15 and 1 wt%, followed by a rapid increase in haze at concentrations exceeding 2 wt%. 相似文献
546.
547.
Martin Bram Leszek NiewolakNikhil Shah Doris SeboldHans Peter Buchkremer 《Journal of power sources》2011,196(14):5889-5896
In the last few years, a lot of effort has been undertaken to reduce the operation temperature of solid oxide fuel cells (SOFCs). Intermediate temperatures in the range of 600-650 °C are thought to be highly attractive due to the expected reduction of high-temperature corrosion and interdiffusion phenomena. Furthermore, each stack operated at higher temperatures has to pass this temperature range during thermal cycling. In this work, a study has been carried out to investigate the interaction between interconnect steel (DIN 1.4760) and vermiculite mica paper filled with talc at 600 °C. Mica paper has been implemented recently as a new sealing material for SOFC stacks, aiming to replace established but brittle glass ceramics. Corrosion experiments were conducted at 600 °C under dual gas atmosphere conditions as well as in air. The interconnect steel showed the formation of non-protective oxide scales in contact with mica, especially in the presence of air. The morphology of oxide scales was investigated by SEM/EDX. Possible reasons for this unexpected result are discussed. The complete encapsulation of mica by embossed and welded sheets made of FeCrAlY-steel (DIN 1.4767) as well as the pre-oxidation of interconnect steel were investigated as solutions to this problem. Pre-oxidation was found to be a promising measure to protect the interconnect steel from breakaway oxidation in contact with mica. 相似文献
548.
Christian Mielke Doris Pospiech Justus Kuhnigk Andreas Korwitz Hartmut Komber Ricardo Bernhardt Nico Krebs Regine Boldt Holger Ruckdäschel Brigitte Voit 《大分子材料与工程》2023,308(10):2300281
The interest in bio-based alternatives to classical polyesters such as poly(ethylene terephthalate) (PET) and poly(butylene terephthalate) (PBT) is steadily growing to achieve a more sustainable approach to polymer materials. In this study, PBT/poly(butylene furanoate) (PBF) blends are prepared, characterized and extrusion foamed. PBF as a bio-based polyester offers two advantages. The ecological footprint of the material is reduced, and additionally, it can be used in Diels-Alder reactions at the blend surface to support fusion of the foamed beads. The blending behavior of the polyesters is investigated using samples prepared in a microcompounder, particularly focused on the miscibility of the blends and transesterification reactions. The blends are thermodynamically immiscible but show a certain degree of transesterification according to nuclear magnetic resonance (NMR) spectroscopy. The morphology of blend beads produced by an extrusion foaming process is analyzed regarding their cell density, cell size distribution, and open-cell content. It is shown that PBF has a positive effect on the bead foam morphology. The use of a bifunctional linker designed for chemical fusion of the bead surfaces allows to obtaining of molded parts, in contrast to beads containing pure PBT. 相似文献
549.
550.
Nina Schmid Kim-Gwendolyn Dietrich Ignasi Forne Alexander Burges Magdalena Szymanska Rina Meidan Doris Mayr Artur Mayerhofer 《International journal of molecular sciences》2021,22(4)
Sirtuins (SIRTs) are NAD+-dependent deacetylases that regulate proliferation and cell death. In the human ovary, granulosa cells express sirtuin 1 (SIRT1), which has also been detected in human tumors derived from granulosa cells, i.e., granulosa cell tumors (GCTs), and in KGN cells. KGN cells are an established cellular model for the majority of GCTs and were used to explore the role of SIRT1. The SIRT1 activator SRT2104 increased cell proliferation. By contrast, the inhibitor EX527 reduced cell numbers, without inducing apoptosis. These results were supported by the outcome of siRNA-mediated silencing studies. A tissue microarray containing 92 GCTs revealed nuclear and/or cytoplasmic SIRT1 staining in the majority of the samples, and also, SIRT2-7 were detected in most samples. The expression of SIRT1–7 was not correlated with the survival of the patients; however, SIRT3 and SIRT7 expression was significantly correlated with the proliferation marker Ki-67, implying roles in tumor cell proliferation. SIRT3 was identified by a proteomic analysis as the most abundant SIRT in KGN. The results of the siRNA-silencing experiments indicate involvement of SIRT3 in proliferation. Thus, several SIRTs are expressed by GCTs, and SIRT1 and SIRT3 are involved in the growth regulation of KGN. If transferable to GCTs, these SIRTs may represent novel drug targets. 相似文献