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71.
72.
73.
Riitta Puupponen‐Pimiä Tuulikki Seppänen‐Laakso Matti Kankainen Johanna Maukonen Riitta Törrönen Marjukka Kolehmainen Tiina Leppänen Eeva Moilanen Liisa Nohynek Anna‐Marja Aura Kaisa Poutanen Francisco A. Tómas‐Barberán Juan C. Espín Kirsi‐Marja Oksman‐Caldentey 《Molecular nutrition & food research》2013,57(12):2258-2263
Ellagitannins are polyphenols abundant in strawberries, raspberries, and cloudberries. The effects of a mixture of these berries were studied in a randomized controlled trial with subjects having symptoms of metabolic syndrome. The study focused on serum lipid profiles, gut microbiota, and ellagitannin metabolites. The results indicate that bioavailability of ellagitannins appears to be dependent on the composition of gut microbiota. 相似文献
74.
Ricardo Morales Luis Melo Aura Llanos Joaquín Brito Yraida Díaz Luis Albornoz Delfín Moronta 《Catalysis Letters》2003,89(1-2):99-104
Bifunctional monometallic Pt/H[Al]ZSM5, Sn/H[Al]ZSM5 and bimetallic Pt-Sn/H[Al]ZSM5 (tin atomic fraction, X
Sn, of 0.46) catalysts were prepared and characterized by means of XPS, EPR, TEM and toluene hydrogenation. The species on their surface as well as the presence of an effect of the electronic and/or geometric type between Pt and Sn in the bimetallic catalyst, which would result in the existence of reduced tin species (Sn0 and/or Sn-Pt), were determined. These species were determined through XPS and would explain the decrease in the hydrogenating activity in the toluene hydrogenation reaction. 相似文献
75.
Transesterification of soy lecithin by lipase and phospholipase 总被引:8,自引:0,他引:8
Anna-Marja Aura Pirkko Forssell Annikka Mustranta Kaisa Poutanen 《Journal of the American Oil Chemists' Society》1995,72(11):1375-1379
Soy lecithin was modified by enzymatic transesterification in a solvent-free system. 1,3-SpecificRhizomucor miehei lipase was found to be efficient in the transesterification with lauric acid and oleic acid, where oleic acid was more incorporated
into soy lecithin. Phospholipase A2 incorporated lauric acid hardly at all, but it hydrolyzed lecithin efficiently. The mixture of lipase and phospholipase A2 (1:1, w/w) incorporated lauric acid to the same extent as did 1,3-specific lipase alone at the same total enzyme concentration.
The main fatty acids replaced were palmitic and linoleic acids by 1,3-specific lipase and its mixture with phospholipase A2, and linoleic and linolenic acids by phospholipase A2 alone, suggesting an improved oxidative stability of the resulting product. Hydrolysis could not be prevented, but it could
be regulated by incubation time and by enzyme dosage. The minimal water content for significant incorporation of lauric acid
into lecithin was below 0.5% of the weight of the reaction mixture. 相似文献
76.
Anna-Marja Aura Pirkko Forssell Annikka Mustranta Tapani Suortti Kaisa Poutanen 《Journal of the American Oil Chemists' Society》1994,71(8):887-891
Enzymatic hydrolysis of oat and soy lecithins and its effects on the functional properties of lecithins were investigated.
The phospholipase used was most efficient at low enzyme and substrate concentrations. More fatty acids were released from
soy lecithin than from oat lecithin. The maximum degree of hydrolysis was 760 μmol free fatty acids per gram soy lecithin
and 170 μmol free fatty acids per gram oat lecithin. On the basis of the total carbohydrate and phosphorus contents in the
polar fractions of the lecithins, oat lecithin contained more glycolipids and less phospholipids than soy lecithin. With regard
to functional properties, the stability of oil-in-water emulsions was enhanced by hydrolyzed soy lecithin and by crude and
hydrolyzed oat lecithins, but only hydrolyzed soy lecithin prevented the recrystallization of barley starch. The dissociation
enthalpy of amylose-lipid-complex (AML-complex) was significantly higher when hydrolyzed soy lecithin was present. Hydrolyzed
oat lecithin slightly affected the dissociation enthalpy of AML-complex. The other lecithins had no effect on recrystallization
or dissociation enthalpies in the barley-starch matrix. 相似文献
77.
78.
Editorial Introduction
Guest Editorial:Special Issue on Spatial Economic Activity Analysis: New Methodologies 相似文献79.
In a multirate wireless network, low data rate nodes consume proportionately more channel resources than high data rate nodes,
resulting in low overall network performance. The use of multiple non-overlapping frequency channels in multirate wireless
networks can overcome the performance degradation by having nodes communicate on different channels based on their data rates.
However, no effort has been invested to utilize the multiple channels for a multirate wireless network. In this paper, we
introduce the Data Rate Adaptive Channel Assignment (DR-CA) algorithm for a multichannel multirate single-hop wireless network
to provide higher network throughput and network efficiency. The main idea is to assign links having same or comparable data
rates on the same channel to minimize the wastage of channel resources due to interference between high data links and low
data rate links. We also design a new Intermediary Multichannel Layer (IML) which resides between network layer and link layer,
at which we implement the DR-CA algorithm. The IML design requires no modifications to the underlying MAC layer and upper
layers of the network stack. To evaluate the proposed algorithm we define new performance metrics—channel efficiency and network
efficiency for a multichannel multirate wireless network. Using OPNET simulations, we show that the multichannel enhancement
using our proposed algorithm provides significant performance improvement in terms of network throughput, channel efficiency,
and network efficiency over existing approaches in multirate wireless networks. Under heavy load condition, the network efficiency
using DR-CA algorithm reaches 90% of the maximum limit. To the best of our knowledge, this is the first work to utilize the
benefits of multiple channels in the multirate wireless network environment. 相似文献
80.
Aura Conci 《International journal for numerical methods in engineering》1992,33(10):2109-2127
A finite element formulation for geometric non-linear analysis of elastic straight thin-walled beams is presented. The updated Lagrangian procedure is used for a stiffness matrix derivation-to analyse large displacements or buckling behaviour of space frames. The stiffness matrix is developed for a generic cross-section and is equally efficient for symmetric, monosymmetric or asymmetric open sections. Some non-linear strain terms usually neglected in the literature have been considered, resulting in a formulation which also includes the initial bimoment and torsion effect for all cross-sections analysed. The proposed method has been implemented and the results of sample problems are presented. 相似文献