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41.
Alternative ways for increased appetite control are today widely sought for due to the growing global health issues connected to obesity. In in vivo studies, oat has been proven an attractive candidate for inducing satiety. Oat is rich in polar lipids, of which the galactolipids are especially interesting, and a hypothesis is that these lipids play an important role for the ileal brake mechanism. In this study, the aim is to investigate the role of polar oat lipids on pancreatic lipolysis rate, using a pH-stat based in vitro digestion model of the duodenum. Lipolysis of oat oil, a mix of oat oil/rapeseed oil (RSO), as well as a liquid oat base (OB) simulating an oat drink with different polar lipid content are investigated, and compared with RSO as control. Increasing the polar lipid content of the product digested leads to a significantly decreased lipolysis rate, and this effect is even observed when mixing RSO with a low amount of oat oil (10%). The results support the hypothesis that polar lipids can delay lipolysis also in a complex, natural system like the liquid OB, and even a minor amount of oat lipids can have large effect on lipolysis rates. Practical applications: The number of studies connecting galactolipids with a decreasing effect on duodenal lipolysis is growing; however, the mechanism behind this phenomenon is still not clarified. Here, the same effect is seen in a complex, natural food system. These findings open up for interesting future food products, where inclusion of oat oil, even at low concentrations, can have a prolonging effect on satiety. Oat for human consumption is an increasing market, thanks to the positive health benefits oat has been connected to, in combination with the current trend toward climate-friendly plant-based options for meat and dairy products. It is believed that oat oil can be attractive as an ingredient in various food products, for example, protein bars and spreads. More studies are needed to confirm the results in vivo. However, a great potential is seen for the use of oat oil to enhance appetite control.  相似文献   
42.
CrAlYN coatings with different Y contents (0, 5 and 12 at.%) were deposited by cathodic arc evaporation to investigate the influence of Y-addition on the structure, mechanical and thermal properties of CrAlN coatings by using X-ray diffraction, scanning electron microscopy, differential scanning calorimetry, thermal gravimetric analysis and nanoindentation. The structural transformation of single phase cubic Cr0.42Al0.58N and Cr0.39Al0.56Y0.05N coatings to cubic–wurtzite mixed Cr0.32Al0.56Y0.12N coating leads to a drop in hardness from (30.2±0.7) GPa of Cr0.42Al0.58N and (32.0±1.0) GPa of Cr0.39Al0.56Y0.05N to (25.2±0.7) GPa of Cr0.32Al0.56Y0.12N. The incorporation of 5 at.% Y retards the thermal decomposition of CrAlN, verified by the postponed precipitation of w-AlN and N-loss upon annealing. Correspondingly, Cr0.39Al0.56Y0.05N coating consistently exhibits the highest hardness value during thermal annealing. Nevertheless, alloying with Y exerts an adverse effect on the oxidation resistance of CrAlN.  相似文献   
43.
We propose a general framework to study the relationship between the price of a painting and its color‐related attributes. To this end we focus on four key aspects: dominant colors, features of the color palette, color harmony, and color emotions. We demonstrate the usefulness of this approach with an example based on Mark Rothko's post‐1950 paintings (the “rectangular” series), and auction data from the 1994 to 2018 period. We identify two distinct price‐color regimes in Rothko's market: (a) [1994‐2005], a period in which prices are explained mainly by the growing popularity of the artist regardless of the color attributes of the paintings sold; and (b) [2006‐2018], a period in which color‐related attributes explain most of the prices. Furthermore, we find that in this second period, the dominant colors and the diversity of the color palette, are by far the most relevant attributes that influence the price; color harmony and color emotions hold almost no explanatory power during this period. Finally, we propose a new metric based on the Herfindahl Index to describe color diversity; this metric seems to be promising at characterizing the effect of the color palette on the price of a painting.  相似文献   
44.
Accessing aldehydes from carboxylate moieties is often a challenging task. In this regard, carboxylate reductases (CARs) are promising catalysts provided by nature that are able to accomplish this task in just one step, avoiding over-reduction to the alcohol product. However, the heterologous expression of CARs can be quite difficult due to the excessive formation of insoluble protein, thus hindering further characterization and application of the enzyme. Here, the heterologous production of the carboxylate reductase from Nocardia otitidiscaviarum (NoCAR) was optimized by a combination of i) optimized cultivation conditions, ii) post-translational modification with a phosphopantetheinyl transferase and iii) selection of an appropriate expression strain. Especially, the selection of Escherichia coli tuner cells as host had a strong effect on the final 110-fold increase in the specific activity of NoCAR. This highly active NoCAR was used to reduce sodium benzoate to benzaldehyde, and it was successfully assembled with an in vitro regeneration of ATP and NADPH, being capable of reducing about 30 mM sodium benzoate with high selectivity in only 2 h of reaction.  相似文献   
45.
Developing the thermal stability of metal-based ceramic composites or their films has always been challenging and bottlenecks for the utilization of energy. In this paper, the novel mesh-like functional Al doped-MoO3 nanocomposite film with even distribution and high purity was firstly fabricated by the high-efficiency electrophoretic deposition and surface modification. The optimal suspension turned out to be the mixture of isopropanol and the additives of polyethyleneimine and benzoic acid. The microtopography, crystalline structure, environmental resistance and thermal stability were analyzed by field emission scanning electron microscope (FESEM), energy dispersive X-ray (EDX), X-ray diffractometer (XRD), exposure and droplet-impacting test, DSC analysis and ignition test, respectively. The water contact angle and sliding angle of product can reach ~170° and <1°, indicating the excellent anti-wetting property. In addition, the high heat-release (~3180 J/g) of product all kept almost unchangeable after six months exposure experiments, demonstrating the outstanding thermostability. The exquisite design idea here can perfectly match microelectromechanical system (MEMS), providing the valuable reference for fabricating other metal-based high-energy composites with long lifespan for real industrial applications.  相似文献   
46.
Sirtuins (SIRTs), enzymes from the family of NAD+-dependent histone deacetylases, play an important role in the functioning of the body at the cellular level and participate in many biochemical processes. The multi-directionality of SIRTs encourages scientists to undertake research aimed at understanding the mechanisms of their action and the influence that SIRTs have on the organism. At the same time, new substances are constantly being sought that can modulate the action of SIRTs. Extensive research on the expression of SIRTs in various pathological conditions suggests that regulation of their activity may have positive results in supporting the treatment of certain metabolic, neurodegenerative or cancer diseases or this connected with oxidative stress. Due to such a wide spectrum of activity, SIRTs may also be a prognostic markers of selected pathological conditions and prove helpful in assessing their progression, especially by modulating their activity. The article presents and discusses the activating or inhibiting impact of individual SIRTs modulators. The review also gathered selected currently available information on the expression of SIRTs in individual disease cases as well as the biological role that SIRTs play in the human organism, also in connection with oxidative stress condition, taking into account the progress of knowledge about SIRTs over the years, with particular reference to the latest research results.  相似文献   
47.
By choosing a triple block polymer, poly(styrene-b-(ethylene-co-butylene)-b-styrene) (SEBS), as the backbone and adopting a long side-chain double-cation crosslinking strategy, a series of SEBS-based anion-exchange membranes (AEMs) was successively synthesized by chloromethylation, quaternization, crosslinking, solution casting, and alkalization. The 70C16-SEBS-TMHDA membrane showed high OH conductivity (72.13 mS/cm at 80 °C) and excellent alkali stability (only 10.86% degradation in OH conductivity after soaking in 4-M NaOH for 1700 h at 80 °C). Furthermore, the SR was only 9.3% at 80 °C and the peak power density of the H2/O2 single cell was up to 189 mW/cm2 at a current density of 350 mA/cm2 at 80 °C. By introducing long flexible side chains into a polymer SEBS backbone, the structure of the hydrophilic–hydrophobic microphase separation in the membrane was constructed to improve the ionic conductivity. Additionally, network crosslinked structure improved dimensional stability and mechanical properties.  相似文献   
48.
The present study aimed to utilise Dicoccum wheat (DW), barley (BF) and soya flour (SF) in the development of low in vitro starch digestibility (IVSD) and estimated glycaemic index (EGI) PB. The BF and SF are mixed (1:1) (BFSF) and used to replace DW at 25%, 50% and 75% level and compared with 100% DW. The quality characteristics (rheological, physical, textural and chemical), IVSD and EGI of PB were determined. The incorporation of BFSF to DW increased the farinograph water absorption capacity (58.1%–64.2%) and mixing tolerance index (21-68 FU), and decreased the dough development time (4.3–2.8 min) and amylograph pasting properties, respectively. Further, the thickness, shear force and redness were decreased and lightness and yellowness increased. Based on the physico-sensory studies, 50% of BFSF along with emulsifier’s incorporation was optimum without affecting any sensory parameters and this PB had decreased IVSD (31) and EGI (54) when compared to the control 37 and 63, respectively.  相似文献   
49.
以方竹笋中提取的膳食纤维为研究对象,采用动态高压微射流(dynamic high-pressure micro-fluidization, DHPM)在不同压力条件(0,50,100,150,200 MPa)下进行处理,探究其对竹笋膳食纤维(bamboo shoots dietary fiber, BSDF)理化和结构特性的影响。结果表明,随着处理压力的增大,BSDF粒径先增大后减小,当处理压力为150 MPa时,粒径最小,为(370±11) nm,此条件下BSDF的持水力、持油力和膨胀力达到最大,较对照组分别提高了47.74%,50.54%,61.27%,且差异显著(P<0.05)。红外光谱分析表明DHPM处理不会改变BSDF的官能团,但会使BSDF内部的部分氢键断裂和半纤维素、木质素等发生降解;X射线衍射和热重分析表明DHPM处理不会引起BSDF的晶体结构改变,但晶体有序度会下降,进而导致其热稳定性降低;微观结构分析显示DHPM处理会使BSDF颗粒尺寸减小、表面粗糙、组织松散,且当处理压力为200 MPa时,颗粒发生团聚。综上,DHPM可以有效改善BSDF的理化性质,在膳食纤维改性方面具有一定的应用价值。  相似文献   
50.
The materials typically used for oxygen transport membranes, Ba0.5Sr0.5Co0.8Fe0.2O3?δ (BSCF) and La0.6Sr0.4Co0.2Fe0.8O3 (LSCF) tend to decompose due to their low thermochemical stability under reducing atmosphere. Fe- and Co-doped SrTiO3 (SrTi1-x-yCoxFeyO3-δ, x + y ≤ 0.35) (STCF) materials showing an oxygen transport comparable to LSCF have great potential for application in ion-transport-devices. In this study, the thermochemical stability of pure perovskite-structured STCF was investigated after annealing in a syngas atmosphere at 600–900 °C. The phase composition of the materials after annealing was characterized by means of X-ray diffraction (XRD). The thermodynamic activities of SrO, FeO, and CoO in the STCF materials were evaluated using Knudsen effusion mass spectrometry (KEMS). Co-doped SrTiO3 (STC) materials were not stable after annealing in the syngas atmosphere above 5 mol% Co-substitution. Ruddlesden-Popper-like phases and SrCO3 were detected after annealing at 600 °C. In contrast, Fe substitution (STF) showed good stability after annealing in syngas upto 35 mol% substitution.  相似文献   
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