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441.
Juan Manuel Del Fresno Antonio Morata Jorge M. Ricardo-da-Silva Carlos Escott Iris Loira José Antonio Suárez- Lepe 《International Journal of Food Science & Technology》2019,54(9):2690-2699
The ageing on lees is a technique particularly interesting in the production of red wines due to the possibility of enhancing some of their sensory characteristics. Different authors have researched the ultrasound assistance to accelerate this ageing process in wines. The present work evaluated the modification that both fractions, polyphenolic and aromatic, of red wines suffer during the ageing on lees process assisted with ultrasounds and with the addition of oak chips. The results obtained during the experimental design indicate that the ultrasound treatment decreased the concentration of proanthocyanidins (between 20.3% and 32.8% with and without oak chips, respectively) and the total pigment content (with the highest reduction in the control sonicated wine 55.9% without chips and lees and from 47.8% to 48.9% when having oak chips/lees and lees, respectively). In addition, it has been observed that the ultrasound treatment did not affect the amount of fermentative volatile compounds present in the wine but, it increased the concentration of phenolic aldehydes coming from oak wood chips (10.8% in control wine and from 35.92% with oak chips/lees to 55.8% with lees). 相似文献
442.
Iris Loira Antonio Morata Carmen González José Antonio Suárez-Lepe 《Food and Bioprocess Technology》2012,5(7):2787-2796
The selection of glycolytically inefficient yeasts is of interest for producing wines with less ethanol, especially when they can also improve their sensorial properties. The selection criteria used in the present study included low fermentative power and high production of secondary metabolites with a positive sensorial impact on red wine. Yeast strains were assayed at different must sugar concentrations and fermentation temperatures. Gas chromatograph with a flame ionisation detector was used to determine volatile glycolytic metabolites, and enzyme tests were employed to determine non-volatile compounds. Taking both laboratory and winery experimental results together, strain TP2A16 was found to show glycolytic inefficiency, reducing the mean ethanol content by 1% by volume in fermentations at 25?°C. From a sensorial point of view, this strain showed good production of glycerine and ethyl lactate. It also showed good production of acetaldehyde, which favours the production of stable pigments. 相似文献
443.
444.
Iris Trefflich Afraa Jabakhanji Juliane Menzel Michael Blaut Andreas Michalsen Alfonso Lampen 《Critical reviews in food science and nutrition》2020,60(17):2990-3004
AbstractIt is assumed that diet influences the composition of gut microbiota, which in turn may affect human health status. This systematic review aimed to summarize associations of a vegan or vegetarian diet with the composition of microbiota. A literature search was conducted in PubMed and Embase for eligible human studies with vegan or vegetarian diets as an exposure and microbiota composition as an outcome in healthy adults. Furthermore, data from our cross-sectional study with vegan participants were included. Out of sixteen included studies, six investigated the association between gut microbiota composition in both vegans and in vegetarians, six in vegans and four studies in vegetarians compared to omnivores, respectively. Among 5 different phyla, 28 families, 96 genera and 177 species, Bacteroides, Bifidobacterium and Prevotella were the most reported genera, followed by the species Prevotella copri, Faecalibacterium prausnitzii and Escherichia coli in all diets. No consistent association between a vegan diet or vegetarian diet and microbiota composition compared to omnivores could be identified. Moreover, some studies revealed contradictory results. This result could be due to high microbial individuality, and/or differences in the applied approaches. Standardized methods with high taxonomical and functional resolutions are needed to clarify this issue. 相似文献
445.
Iris Ribitsch Andrea Bileck Monika Egerbacher Simone Gabner Rupert L. Mayer Lukas Janker Christopher Gerner Florien Jenner 《International journal of molecular sciences》2021,22(23)
Fetal cartilage fully regenerates following injury, while in adult mammals cartilage injury leads to osteoarthritis (OA). Thus, in this study, we compared the in vivo injury response of fetal and adult ovine articular cartilage histologically and proteomically to identify key factors of fetal regeneration. In addition, we compared the secretome of fetal ovine mesenchymal stem cells (MSCs) in vitro with injured fetal cartilage to identify potential MSC-derived therapeutic factors. Cartilage injury caused massive cellular changes in the synovial membrane, with macrophages dominating the fetal, and neutrophils the adult, synovial cellular infiltrate. Correspondingly, proteomics revealed differential regulation of pro- and anti-inflammatory mediators and growth-factors between adult and fetal joints. Neutrophil-related proteins and acute phase proteins were the two major upregulated protein groups in adult compared to fetal cartilage following injury. In contrast, several immunomodulating proteins and growth factors were expressed significantly higher in the fetus than the adult. Comparison of the in vitro MSCs proteome with the in vivo fetal regenerative signature revealed shared upregulation of 17 proteins, suggesting their therapeutic potential. Biomimicry of the fetal paracrine signature to reprogram macrophages and modulate inflammation could be an important future research direction for developing novel therapeutics. 相似文献
446.
In computer vision, motion analysis is a fundamental problem. Applying the concepts of congruence checking in computational geometry and geometric hashing, which is a technique used for the recognition of partially occluded objects from noisy data, we present a new random sampling approach for the estimation of the motion parameters in two- and three-dimensional Euclidean spaces of both a completely measured rigid object and a partially occluded rigid object. We assume that the two- and three-dimensional positions of the vertices of the object in each image frame are determined using appropriate methods such as a range sensor or stereo techniques. We also analyze the relationships between the quantization errors and the errors in the estimation of the motion parameters by random sampling, and we show that the solutions obtained using our algorithm converge to the true solutions if the resolution of the digitalization is increased. 相似文献
447.
Iris D. Tommelein David R. Riley Greg A. Howell 《Canadian Metallurgical Quarterly》1999,125(5):304-310
The Parade Game illustrates the impact work flow variability has on the performance of construction trades and their successors. The game consists of simulating a construction process in which resources produced by one trade are prerequisite to work performed by the next trade. Production-level detail, describing resources being passed from one trade to the next, illustrates that throughput will be reduced, project completion delayed, and waste increased by variations in flow. The game shows that it is possible to reduce waste and shorten project duration by reducing the variability in work flow between trades. Basic production management concepts are thus applied to construction management. They highlight two shortcomings of using the critical-path method for field-level planning: The critical-path method makes modeling the dependence of ongoing activities between trades or with operations unwieldy and it does not explicitly represent variability. The Parade Game can be played in a classroom setting either by hand or using a computer. Computer simulation enables students to experiment with numerous alternatives to sharpen their intuition regarding variability, process throughput, buffers, productivity, and crew sizing. Managers interested in schedule compression will benefit from understanding work flow variability's impact on succeeding trade performance. 相似文献
448.
Modern lifestyles, new demographic trends, and the expansion of the European Community are changing the European countryside. At stake are cultural landscapes, their richness in wildlife, historical interest, scenic beauty, and the recreational opportunities they provide. Visible phenomena of change are symptoms of a growing socio-economic and ecological disparity between different regions. Agreements on AGENDA 2000 European policy provide a new platform for regional and agricultural development. The paper explores which landscape dynamics are in store. Employing examples from rural Germany, the paper presents corridors of possible futures for unique, and at the same time, dynamic places. Modern strategies of landscape and urban planning are discussed which aim at closer co-operation between a multitude of stakeholders, policy makers, planners, and other agents of change. Methods and tools are needed to build consensus among ever increasing numbers of participants representing potentially wide ranges of values. 相似文献
449.
A series of short chain fatty acid derivatives of aminimides were shown to possess hypolipidemic activity in rats and mice.
Most of the agents tested lowered both serum cholesterol and triglyceride levels by at least 30% in mice and were effective
in hyperlipidemic induced mice. 1,1-Dimethyl-1-(2-hydroxypropyl)-amine mersitimide lowered serum cholesterol levels 41% and
serum triglyceride levels 56% at 20 mg/kg/day I.P. after 16 days. The same agent was active orally when administered to rats
with a 38% reduction in serum cholesterol and a 52% reduction in serum triglycerides after 14 days. The agents inhibited liver
acetyl CoA synthetase, ATP dependent citrate lyase and phosphatidate phosphohydrolase activities in vitro and in vivo. Reduction
of cholesterol, triglycerides, neutral lipids and phospholipid levels were noted in the livers of mice treated for 16 days.
In rat studies, cholesterol, triglyceride and phospholipid levels were reduced in liver, small intestine and the feces after
two weeks' dosing. The cholesterol content was reduced in the very low density lipoprotein (VLDL) and low density lipoprotein
(LDL) fractions but elevated in the high density lipoproteins (HDL). Triglyceride levels were lowered in the VLDL, and neutral
lipid levels were reduced in the chylomicron and VLDL fractions. 相似文献
450.