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31.
Moderate alcohol consumption is associated with increased plasma high-density lipoprotein (HDL)-cholesterol concentrations and reduced risk for cardiovascular disease. Plasma cholesteryl ester transfer activity (CETA) mediates the exchange of HDL-cholesteryl ester (CE) for the triacylglycerol (TAG) of very-low-density lipoproteins. We compared the effects of oral challenges of Alcohol, saturated fat (SAT), and (Alcohol + SAT) on plasma CETA, cholesterol, nonesterified fatty acids (NEFA), and TAG among normo-triglyceridemic (NTG) and mildly hypertriglyceridemic (HTG) volunteers having a range of plasma TAG concentrations. The major changes were (1) CETA increased more after ingestion of SAT and (Alcohol + SAT) in the HTG group versus the NTG group; (2) after all three challenges, elevation of plasma TAG concentration persisted longer in the HTG versus NTG group. Plasma cholesterol was not affected by the three dietary challenges, while Alcohol increased NEFA more in the HTG group than the NTG group. Plasma TAG best predicted plasma CETA, suggesting that intestinally derived lipoproteins are acceptors of HDL-CE. Unexpectedly, ingestion of (Alcohol + SAT) reduced the strength of the correlation between plasma TAG and CETA, that is the effects of (SAT and Alcohol) on plasma CETA are not synergistic nor additive but rather mutually suppressive. The alcohol-mediated inhibition of CE-transfer to chylomicrons maintains a higher plasma HDL-cholesterol concentration, which is athero-protective, although the suppressive metabolite underlying this correlation could be acetate, the terminal alcohol metabolite, other factors, including CETA inhibitors, are also likely important. 相似文献
32.
Expanded gamut printing is an approach in color reproduction that expands the color gamut of conventional CMYK printing processes via the use of additional colorants, such as Orange, Green, and Violet inks. This study evaluates the ability of commercial color management software to create an accurate solution for an expanded gamut printing system. In this study, two printing processes were used, an Epson SureColor P9000 inkjet printer/proofer and an HP Indigo 7900 digital production press, both with 7-color expanded gamut ink sets. Software solutions from Alwan, CGS ORIS, ColorLogic, GMG Color, Heidelberg, and Kodak were evaluated. The systems were tested to see how well they could reproduce the colors in the entire PANTONE+ Solid Coated spot color library. It is shown that the solutions are able to reproduce 89% to 94% of the spot colors on the Epson P9000 inkjet printer and 77% to 87% of the library on the Indigo 7900, both to less than two CIEDE2000 (a typical tolerance in label and packaging work). The number of color patches in expanded gamut characterization test charts was noted, as this is still an area of proprietary, nonstandardized working practice. There are many different colorant combinations that can make the same color in expanded gamut printing. The ink build created by the different software solutions was studied, as it relates to press stability through appropriate choice of colorants. Pantone and Adobe provide everyday commercial tools for expanded color workflows. The study identified some issues with products from these companies that could confuse a less-skilled user in a busy production environment. The conclusion of the study is that expanded gamut solutions for spot color printing produce totally acceptable results for digital printing processes; expanded gamut printing is ready, here and now. The findings show that expanded gamut printing can replace cumbersome conventional spot color workflows creating considerable savings and advantages, especially for label and packaging printers. 相似文献
33.
To design robust interval observers for uncertain continuous‐time linear systems, a new set‐integration approach is proposed to compute trajectory tubes for the estimation error. Because this approach, the order‐preserving condition on the dynamics of the estimation error is no longer required. Therefore, synthesis methods can be used to compute observer gains that reduce the impact of the system uncertainties on the accuracy of the estimated state enclosures. The performance of the proposed approach is showcased through illustrative numerical examples. 相似文献
34.
Michaela K. Thielen Cody K. Vaneerd Dr. Manibarsha Goswami Prof. Dr. Erin E. Carlson Prof. Dr. John F. May 《Chembiochem : a European journal of chemical biology》2020,21(24):3500-3503
One promising strategy to combat antibiotic-resistant bacteria is to develop compounds that block bacterial defenses against antibacterial conditions produced by the innate immune system. Salmonella enterica, which causes food-borne gastroenteritis and typhoid fever, requires histidine kinases (HKs) to resist innate immune defenses such as cationic antimicrobial peptides (CAMPs). Herein, we report that 2-aminobenzothiazoles block histidine kinase-dependent phenotypes in Salmonella enterica serotype Typhimurium. We found that 2-aminobenzothiazoles inhibited growth under low Mg2+, a stressful condition that requires histidine kinase-mediated responses, and decreased expression of the virulence genes pagC and pagK. Furthermore, we discovered that 2-aminobenzothiazoles weaken Salmonella’s resistance to polymyxin B and polymyxin E, which are last-line antibiotics and models for host defense CAMPs. These findings raise the possibilities that 2-aminobenzothiazoles can block HK-mediated bacterial defenses and can be used in combination with polymyxins to treat infections caused by Salmonella. 相似文献
35.
36.
Dr. Luca Gobbi Dr. Joël Mercier Dr. Benny Bang-Andersen Dr. Jean-Marie Nicolas Dr. John Reilly Björn Wagner Dr. David Whitehead Dr. Emmanuelle Briard Dr. R. Paul Maguire Dr. Edilio Borroni Dr. Yves P. Auberson 《ChemMedChem》2020,15(7):560-560
Nonspecific binding (NSB) is a key parameter in optimizing PET imaging tracers. We compared the ability to predict NSB of three available methods: LIMBA, rat fu,brain, and CHI(IAM). Even though NSB is often associated with lipophilicity, we observed that logD does not correlate with any of these assays, clearly indicating that lipophilicity, while influencing NSB, is insufficient to predict it. A cross-comparison of the methods showed that all three correlate and are useful predictors of NSB. The three assays, however, rank the molecules slightly differently, illustrating the challenge of comparing molecules within a narrow chemical space. We also noted that CHI(IAM) values more effectively predict VNS, a measure of in vivo NSB in the human brain. CHI(IAM) measurements might be a closer model of the actual physicochemical interaction between PET tracer candidates and cell membranes, and seems to be the method of choice for the optimization of in vivo NSB. 相似文献
37.
Hansung Kim Md. Towfiq Tofail Ciby John 《JOM Journal of the Minerals, Metals and Materials Society》2018,70(4):473-478
Among a variety of solar cell types, thin-film solar cells have been rigorously investigated as cost-effective and efficient solar cells. In many cases, flexible solar cells are also fabricated as thin films and undergo frequent stress due to the rolling and bending modes of applications. These frequent motions result in crack initiation and propagation (including delamination) in the thin-film solar cells, which cause degradation in efficiency. Reliability evaluation of solar cells is essential for developing a new type of solar cell. In this paper, we investigated the effect of layer delamination and grain boundary crack on 3D thin-film solar cells. We used finite element method simulation for modeling of both electrical performance and cracked structure of 3D solar cells. Through simulations, we quantitatively calculated the effect of delamination length on 3D copper indium gallium diselenide (CIGS) solar cell performance. Moreover, it was confirmed that the grain boundary of CIGS could improve the solar cell performance and that grain boundary cracks could decrease cell performance by altering the open circuit voltage. In this paper, the investigated material is a CIGS solar cell, but our method can be applied to general polycrystalline solar cells. 相似文献
38.
In this research, the three‐dimensional structural and colorimetric modeling of three‐dimensional woven fabrics was conducted for accurate color predictions. One‐hundred forty single‐ and double‐layered woven samples in a wide range of colors were produced. With the consideration of their three‐dimensional structural parameters, three‐dimensional color prediction models, K/S‐, R‐, and L*a*b*‐based models, were developed through the optimization of previous two‐dimensional models which have been reported to be the three most accurate models for single‐layered woven structures. The accuracy of the new three‐dimensional models was evaluated by calculating the color differences ΔL*, ΔC*, Δh°, and ΔECMC(2:1) between the measured and the predicted colors of the samples, and then the error values were compared to those of the two‐dimensional models. As a result, there has been an overall improvement in color predictions of all models with a decrease in ΔECMC(2:1) from 10.30 to 5.25 units on average after the three‐dimensional modeling. 相似文献
39.
Chengsheng Ni Mark Cassidy John T.S. Irvine 《Journal of the European Ceramic Society》2018,38(16):5463-5470
Image analysis and quantification were performed on porous scaffolds for building SOFC cathodes using the two types of YSZ powders. The two powders (U1 and U2) showed different particle size distribution and sinterability at 1300?°C. AC impedance on symmetrical cells was used to evaluate the performance of the electrode impregnated with 35-wt.% La0.8Sr0.2FeO3. For example, at 700?°C, the electrode from U2 powder shows a polarization resistance (Rp) of 0.21?Ω?cm2, and series resistance (Rs) of 8.5?Ω?cm2 for an YSZ electrolyte of 2-mm thickness, lower than the electrode from U1 powder (0.25?Ω?cm2 for Rp and 10?Ω?cm2 for Rs) does. The quantitative study on image of the sintered scaffold indicates that U2 powder is better at producing architecture of high porosity or long triple phase boundary (TPB), which is attributed as the reason for the higher performance of the LSF-impregnated electrode. 相似文献
40.
Rizwan Ahmed Malik Ali Hussain Matias Acosta John Daniels Hyoung-Su Han Myong-Ho Kim Jae-Shin Lee 《Journal of the European Ceramic Society》2018,38(6):2511-2519
In this work, the relationship between the structural mechanisms and macroscopic electrical properties of the Nb-modified 0.96(Bi0.5Na0.84K0.16TiO3)–0.04SrTiO3 (BNKT–ST) system were elucidated by using temperature dependent and in situ synchrotron X-ray diffraction (XRD) techniques. For the composition x?=?0.0175, a large-signal piezoelectric coefficient (Smax/Emax?=?d33*) of 735 pm?V?1 at 6?kV mm?1 was observed at room temperature. Interestingly, at a higher temperature of 110?°C, the sample still showed a large d33* of 570 pm V?1. Furthermore, the temperature-invariant electrostrictive coefficient for this sample was found to be 0.0285?m4?C?2 over the temperature range of 25–170?°C. Moreover, the energy density for x?=?0.030 sample was ~1.0?J?cm?3 with an energy storage efficiency of ?70% in the temperature range of 25–135?°C. These results suggest that the synthesized Nb-modified BNKT–ST system is promising for the design of ceramic actuators as well as capacitor applications. 相似文献