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1.
The present study aimed to investigate the effect of somatic cell count (SCC) of raw cow's milk on the volatile organic compound (VOC) profiles of yoghurt. Test yoghurt samples were produced from three batches of cow's milk with low, medium and high SCC, respectively. The VOCs were determined by gas chromatography–mass spectrometry (GC–MS) analysis. A lower diacetyl and acetoin content and a higher content of 2‐heptanone, and butanoic and hexanoic acids were established in the yoghurt samples from batches with high SCC of above 1 000 000 cells/cm3. The increased SCC of cow's milk had a negative effect on the volatile organic compound profiles of yoghurt.  相似文献   
2.
We present a short and rather informal account concerning a problem we posed in earlier work, recall our conjecture at the time, and report on our answer today. Specifically, our purpose is to draw attention to fiberwise topology as a possible mathematical tool for formalizing multi-colored images and other complex signals met in pattern recognition (P.R.), to provide some information concerning the mathematical background of the fiber topological machinery, and indicate how to use it. For a detailed technical study as well as a tentative hierarchical classification of topological images in growing order of complexity and the corresponding topological processing methods, the readers may consult Pavel [5]. The paper ends by mentioning some artificial intelligence (A.I.) aspects of the fiberwise imagery.  相似文献   
3.
This paper analyses the determination of visibility of journals in which researchers of INRA (National Institute for Agricultural Research) publish. The corpus is comprised of 671 articles published over a period of four years in 258 journals. The advantage of the method applied for determining the visibility of journals is that it combines two approaches: a) bibliometric indicators (coverage by the ISI-publications and by two specific French databases) and b) experts' opinions (10 economists and sociologists). The main results are: a) There is a convergence between the opinion of the experts and «visibility» in the databases, b) The impact factor confirms the main opinions of the experts. The first journals ranked by the experts and JCR Social Sciences are the same but represent only 40 per cent of the total journals analysed. The other journals were revealed by the experts and French databases.«Whoever seeks to pass a balanced but lucid judgement on the general trends of the activity carried out by the profession to which he belongs, is liable to say either banalities or to hurt his colleagues»The notion which we retain of core is that which is successively and conjointly validated by the experts and by the major databases representative of the field.This study was financed by the Department of Rural Economy and Sociology of INRA.  相似文献   
4.
The study evaluated the effects of waxing, irradiation dose and post‐irradiation storage time on the essential oils in orange peel. Mature oranges (Maroc late) waxed or unwaxed were treated with 1 or 2 kGy radiation and stored for 9 weeks at 20 °C and 40–50% RH. Essential oils from the peel were extracted and analysed by GC. Results showed that D ‐limonene was significantly lower in waxed oranges; levels in samples treated with 2 kGy were higher than those in non‐irradiated or treated with 1 kGy. Linalool, methyl anthranilate and 3,7‐dimethyl‐2,6‐octadienal decreased as the dose increased. Levels of linalool increased with storage time but D ‐limonene was unaffected. These results may aid in guaranteeing the quality of orange essential oils during storage time. Copyright © 2004 Society of Chemical Industry  相似文献   
5.
Twenty-eight experienced handlers, considered the best in two transport companies, were interviewed using a questionnaire consisting of partially closed-ended questions. They had to assess 20 videotape handling sequences showing two different handling methods to determine, for 10 factors and overall, which one was the best. They were asked about the inportance of these factors in their choices of the best method. The aims of the study were to verify whether there was a consensus among experienced handlers as to what was a good handling method and to identify the factors taken into consideration by them. Results show the lack of consensus on the best methods. Handlers favor different strategies depending on the worjk context and their own priorities.  相似文献   
6.
The powder mixtures used for diffusion galvanizing (Zn + inert filler + activator) have the following deficiencies: susceptibility to sintering and fusing under elevated CTT temperatures, complexity of correcting the set of components in repeated use of the mixtures and the related instability of the results obtained, complexity of regeneration of worked-out mixtures, elevated ecological hazard of their use, etc. This explains the need for the present work, which shows that most of the mentioned deficiencies can be eliminated by an appropriate choice of the mixture components and (or) preliminary treatment of them.  相似文献   
7.
Optimal synthesis of human movement or the prediction of the kinematics of a new movement require not only that the multi-body system be modeled but also that a performance criterion is specified. For sub-maximal movements the selection of a suitable performance criterion, able to generate realistic dynamic behavior is difficult. A two-dimensional simulation model of the take-off phase of a sub-maximal long jump was developed to study the effect of criterion choice on the realism of simulated movements. A parametric optimization technique was employed to obtain solutions to the constrained equations of motion. Seven different criteria were evaluated, by comparing simulated movements with an actual performance, to identify the criterion which most closely approximated that spontaneously minimized by the athlete. Synthesis of the take-off phase of a sub-maximal long jump was found to be sensitive to the chosen criterion, with a criterion based on minimizing joint intersegmental forces found to perform well.  相似文献   
8.
Iron is a critical metal for several vital biological processes. Most of the body’s iron is bound to hemoglobin in erythrocytes. Iron from senescent red blood cells is recycled by macrophages in the spleen, liver and bone marrow. Dietary iron is taken up by the divalent metal transporter 1 (DMT1) in enterocytes and transported to portal blood via ferroportin (FPN), where it is bound to transferrin and taken up by hepatocytes, macrophages and bone marrow cells via transferrin receptor 1 (TfR1). While most of the physiologically active iron is bound hemoglobin, the major storage of most iron occurs in the liver in a ferritin-bound fashion. In response to an increased iron load, hepatocytes secrete the peptide hormone hepcidin, which binds to and induces internalization and degradation of the iron transporter FPN, thus controlling the amount of iron released from the cells into the blood. This review summarizes the key mechanisms and players involved in cellular and systemic iron regulation.  相似文献   
9.
J.J. Bourguignon  J.C. Galin 《Polymer》1982,23(10):1493-1500
The morphological and hydrodynamic properties of a series of homogeneous fractions of substituted poly(methylmethacrylate) (A units) bearing keto-β-functional groups (B units) of the general structureCOCH2R, with R = SOxCH3 (x = 1,2) or SO2N(CH3)2, were investigated by intrinsic viscosity, light scattering and partial specific volume measurements in dimethylformamide (DMF) solution at 25°C. For molar substitution degrees DSm < 0.5, the copolymers behave as flexible random coils. The Stockmayer-Fixman-Yamakawa analysis of the [η]-M?w data leads to slightly higher unperturbed dimensions Ko and steric factor σ than those for PMMA, and to stronger chain expansion as a result of the weak hydrogen bonding between DMF and COCH2R units and a positive XAB interaction parameter. For DSm > 0.5 however, copolymers bearing COCH2SO2N(CH3)2 groups behave as worm-like chains, as derived from the Fujii-Yamakawa analysis of the [η]-M?w-v? data: the persistence length increases from 380 to 570 Å within the DSm range 0.57–0.75. This transition from a random coil to a worm-like chain for DSm > 0.5 was tentatively correlated with the accumulation of B units in sterically hindered and self-associated short blocks of average length lB ? 1.6 which provide drastically increased rigidity to the copolymer chain.  相似文献   
10.
Mobile applications and services relying on mobility prediction have recently spurred lots of interest. In this paper, we propose mobility prediction based on cellular traces as an infrastructural level service of telecom cloud. Mobility Prediction as a Service (MPaaS) embeds mobility mining and forecasting algorithms into a cloud-based user location tracking framework. By empowering MPaaS, the hosted 3rd-party and value-added services can benefit from online mobility prediction. Particularly we took Mobility-aware Personalization and Predictive Resource Allocation as key features to elaborate how MPaaS drives new fashion of mobile cloud applications. Due to the randomness of human mobility patterns, mobility predicting remains a very challenging task in MPaaS research. Our preliminary study observed collective behavioral patterns (CBP) in mobility of crowds, and proposed a CBP-based mobility predictor. MPaaS system equips a hybrid predictor fusing both CBP-based scheme and Markov-based predictor to provide telecom cloud with large-scale mobility prediction capacity.  相似文献   
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