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81.
Zhiying Zhang Elaine Lanza Penny M. Kris-Etherton Nancy H. Colburn Deborah Bagshaw Michael J. Rovine Jan S. Ulbrecht Gerd Bobe Robert S. Chapkin Terryl J. Hartman 《Lipids》2010,45(9):765-775
Clinical studies have shown that fiber consumption facilitates weight loss and improves lipid profiles; however, the beneficial
effects of high fermentable fiber low glycemic index (GI) diets under conditions of weight maintenance are unclear. In the
Legume Inflammation Feeding Experiment, a randomized controlled cross-over feeding study, 64 middle-aged men who had undergone
colonoscopies within the previous 2 years received both a healthy American (HA) diet (no legume consumption, fiber consumption = 9 g/1,000 kcal,
and GI = 69) and a legume enriched (1.5 servings/1,000 kcal), high fiber (21 g/1,000 kcal), low GI (GI = 38) diet (LG) in
random order. Diets were isocaloric and controlled for macronutrients including saturated fat; they were consumed each for
4 weeks with a 2–4 week break separating dietary treatments. Compared to the HA diet, the LG diet led to greater declines
in both fasting serum total cholesterol (TC) and low density lipoprotein cholesterol (LDL-C) (P < 0.001 and P < 0.01, respectively). Insulin-resistant (IR) subjects had greater reductions in high density lipoprotein cholesterol (HDL-C;
P < 0.01), and triglycerides (TAG)/HDL-C (P = 0.02) after the LG diet, compared to the HA diet. Insulin-sensitive (IS) subjects had greater reductions in TC (P < 0.001), LDL-C (P < 0.01), TC/HDL-C (P < 0.01), and LDL-C/HDL-C (P = 0.02) after the LG diet, compared to the HA diet. In conclusion, a high legume, high fiber, low GI diet improves serum
lipid profiles in men, compared to a healthy American diet. However, IR individuals do not achieve the full benefits of the
same diet on cardiovascular disease (CVD) lipid risk factors. 相似文献
82.
In reverse osmosis systems with high silica water severe and irreversible membrane scaling can be observed. But suitable test methods to find an appropriate antiscalant agent and the optimal dosage are missing. Usually only the silicate concentration in the feed water is regarded.In this paper the results of laboratory experiments about the influence of Ca2+- and Mg2+-ions on the behaviour of supersaturated solutions of silica in different test waters are discussed first. After that the new developed membrane-based test method to determine the effectiveness of antiscalants is presented.The applied different methods of analysis enabled the differentiation of three groups of silicates: ‘monomeric’, ‘polymeric’ and ‘filterable’.With the test method the strong impact of silicate scaling was proven, even if only small amounts of scale had been formed. It could be shown, that the ‘polymeric silica’ is mainly responsible for the membrane scaling. The kinetic of the formation of ‘polymeric silica’ is strongly influenced by the cations and the pH-value. It could be demonstrated that the use of a suitable antiscalant makes it possible to operate the plant at significantly higher recovery rates. 相似文献
83.
In order to select and to apply a porous membrane under supercritical conditions, it is necessary to understand the transport mechanism affecting the permeation behaviour.This paper describes the investigation of gas transport through micro porous ceramic membranes consisting of several layers. The separation layer is made from TiO2 with a nominal pore size diameter of 0.9 nm. Single gas permeation of helium, nitrogen, argon, methane, and carbon dioxide was measured in the temperature range of 293-443 K and in the pressure range of 1-10 MPa.Observation of the permeability of these membranes revealed that the transport of non?adsorbing gases under these conditions is governed by Knudsen diffusion and viscous flow. 相似文献
84.
Lithological and pedological influences on the magnetic susceptibility of soil: their consideration in magnetic pollution mapping 总被引:3,自引:0,他引:3
Hanesch M Rantitsch G Hemetsberger S Scholger R 《The Science of the total environment》2007,382(2-3):351-363
Magnetic susceptibility measurements are widely used to map and monitor the heavy metal pollution of soils. However, the magnetic properties of soils are influenced significantly by the bedrock lithology and soil-forming processes. Therefore, a main challenge in the data interpretation is to filter out the anthropogenic pollution signal. In this study we address this problem by analysing susceptibility values, heavy metal concentrations, as well as pedological parameters in a large soil data set from the eastern segment of Austria, covering a wide range of different lithologies and soil types. The statistic assessment demonstrates an influence of lithology and soil type on the magnetic susceptibility signal. Therefore anomalies are defined in sub sets of different soil types separately. Three different methods were applied to detect susceptibility anomalies: the median absolute deviation method, the boxplot method, and the population modelling method. These methods evaluate topsoil data only and can therefore also be applied to field measurements of magnetic susceptibility. The results were compared to the conventional method of calculating the difference of topsoil and subsoil susceptibility. All three approaches identify the main anomalies in the study area and are successful in circumventing the problem of erroneous anomaly definition due to pedological processes. However, knowledge of the lithological background is still necessary for a meaningful interpretation and can only be substituted by a large amount of data. The tested methods lead to thresholds of different height and therefore act as filters of different strength for the definition of anomalies. 相似文献
85.
Identification and monitoring of metabolite markers of dry bean consumption in parallel human and mouse studies 下载免费PDF全文
86.
Emanuel Ionescu Benjamin Papendorf Hans-Joachim Kleebe Hergen Breitzke Katharina Nonnenmacher Gerd Buntkowsky Ralf Riedel 《Journal of the European Ceramic Society》2012,32(9):1873-1881
The polymer-to-ceramic transformation of a hafnium alkoxide-modified polysilazane was investigated via thermogravimetric analysis coupled with in situ mass spectrometry (TG/MS), nuclear magnetic resonance (MAS NMR) and transmission electron microscopy (TEM). The results indicate that the structural evolution of the polysilazane upon ceramization is strongly affected by the modification with hafnium alkoxide. Thus, the content of carbon in the ceramic backbone was relatively low, whereas a large amount of SiN4 sites and a segregated carbon phase was present in the sample. Furthermore, this study revealed the formation of a SiHfCNO amorphous single phase ceramic via pyrolysis of the polymer at 700 °C, whereas at higher pyrolysis temperatures precipitation of hafnia was observed, leading to an amorphous hafnia/silicon carbonitride ceramic nanocomposite. The precipitation of hafnia was shown to not rely on decomposition processes, but to be a result of rearrangement reactions occurring within the ceramic material. 相似文献
87.
K. Nürnberg Britta Ender Hans-Jürgen Papstein Jochen Wegner Klaus Ender Gerd Nürnberg 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1999,209(6):332-335
The adipose tissue development in muscle and the fatty acid composition of intramuscular fat of 200 bulls from three different breeds during growth was investigated. There were significant differences in quantitative and qualitative fat deposition which were genetically caused. The muscle of Galloway and White-blue Belgian bulls contained a high n–3 fatty acid content which is positive for human nutrition. During growth an increased deposition of saturated fatty acids into the adipocytes of muscle was observed. 相似文献
88.
Earth observation allows the separation of snow cover and cloudiness using multispectral measurements. Several satellite-based snow monitoring services are available, ranging from regional to world-wide scales. Using these data enables photovoltaic (PV) plant management to differentiate between failures due to snow coverage on a PV system and other error sources. Additionally, yield estimates for solar siting are improved. This paper presents a validation study from January to April 2006 comparing satellite-based datasets with ground measurements from German and Swiss meteorological stations. A false alarm rate, an error due to irradiance underestimation, the availability of daily data, and the classification accuracy are introduced as quality metrics. Compared to Switzerland, generally a higher accuracy is found in all datasets for Southern Germany. The most significant difference among the datasets is found in the error pattern shifting from too much snow (which results in an error due to underestimation of irradiance) to too little snow detection, causing a false alarm in PV monitoring.Overall, the data records of the Land Surface Analysis Satellite Application Facility (LSA SAF), the German Aerospace Center (DLR) and the Interactive Multisensor Snow and Ice Mapping System (IMS) are found to be most suitable for solar energy purposes. The IMS dataset has a low false alarm rate (4%) and a good data availability (100%) making it a good choice for power plant monitoring, but the error due to underestimation relevant in site auditing is large with 59%. If a cumulative snow cover algorithm is applied to achieve information every day as needed both for power plant monitoring and site auditing, both the DLR and the LSA SAF datasets are comparable with classification accuracies of 70%, false alarm rates of 37% and 34%, respectively, and errors due to irradiance underestimation in 26% and 27% of all coincidences. 相似文献
89.
90.
Dominik Benz Andreas Hotho Robert Jäschke Beate Krause Folke Mitzlaff Christoph Schmitz Gerd Stumme 《The VLDB Journal The International Journal on Very Large Data Bases》2010,19(6):849-875
Social resource sharing systems are central elements of the Web 2.0 and use the same kind of lightweight knowledge representation,
called folksonomy. Their large user communities and ever-growing networks of user-generated content have made them an attractive object of
investigation for researchers from different disciplines like Social Network Analysis, Data Mining, Information Retrieval
or Knowledge Discovery. In this paper, we summarize and extend our work on different aspects of this branch of Web 2.0 research,
demonstrated and evaluated within our own social bookmark and publication sharing system BibSonomy, which is currently among
the three most popular systems of its kind. We structure this presentation along the different interaction phases of a user
with our system, coupling the relevant research questions of each phase with the corresponding implementation issues. This
approach reveals in a systematic fashion important aspects and results of the broad bandwidth of folksonomy research like
capturing of emergent semantics, spam detection, ranking algorithms, analogies to search engine log data, personalized tag
recommendations and information extraction techniques. We conclude that when integrating a real-life application like BibSonomy
into research, certain constraints have to be considered; but in general, the tight interplay between our scientific work
and the running system has made BibSonomy a valuable platform for demonstrating and evaluating Web 2.0 research. 相似文献