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211.
212.
High‐Affinity Carbohydrate Binding by Trimeric Benzoboroxoles Measured on Carbohydrate Arrays 下载免费PDF全文
Dr. Dorith Claes Elisabeth Memmel Malte Holzapfel Prof. Dr. Jürgen Seibel Prof. Dr. Wolfgang Maison 《Chembiochem : a European journal of chemical biology》2014,15(16):2450-2457
Carbohydrates are involved in a wide range of biological processes of pharmaceutical relevance. The selective recognition of carbohydrates is therefore of great interest in biology and medicine. In this study we present the synthesis of fluorescent multimeric benzoboroxoles and the analysis of multivalent binding processes to immobilized carbohydrate arrays by fluorescence spectroscopy. We observed high binding affinities of trimeric benzoboroxoles by determination of KDsurf values for their interaction with α‐Gal on glass chips. The observed KDsurf values were in the mid‐nM range (49 and 104 nM ) and are comparable to the KDsurf values for binding of natural lectins, such as that of ConA to immobilized α‐Man (79 nM ). The array technology was found to be an excellent tool for studying the binding processes of multivalent lectin mimetics with respect to profiling and quantitation. 相似文献
213.
We report on atomic force microscopy (AFM) in ambient and liquid environments with the qPlus sensor, a force sensor based on a quartz tuning fork with an all-electrical deflection measurement scheme. Small amplitudes, stiff sensors with bulk diamond tips and high Q values in air and liquid allow to obtain high resolution images. The noise sources in air and liquid are analyzed and compared for standard silicon cantilevers and qPlus sensors. First, epitaxial graphene was imaged in air, showing atomic steps with 3 A? height and ridges. As a second sample system, measurements on calcite (CaCO(3)) in liquids were performed in water and polyethylenglycol (PEG). We demonstrate high resolution images of steps in PEG on calcite and nanolithography processes, in particular with frequency-modulation AFM the controlled dissolution of calcite monolayers. 相似文献
214.
This study surveyed the presence of bacterial pathogens in eight Swedish sewage treatment plants (STPs), with four different treatment methods, focusing on detection of zoonotic bacteria in raw and treated sludge. Salmonella spp., Listeria monocytogenes, Campylobacter coli and jejuni, Escherichia coli O157 and indicator bacteria were investigated. Samplings were performed from July 2000 to June 2002, resulting in 64 raw sludge samples and 69 treated sludge samples. The samples from raw sludge (67%) and treated sludge (55%) were positive for Salmonella; 49 different serotypes were detected. Restriction enzyme analysis and pulsed field gel electrophoresis of Salmonella serotypes indicated that Salmonella persists in STPs and that there is a continuous supply of new strains. There are differences in treatment methods concerning the reduction of pathogens and indicator bacteria. If spread on arable land, sludge increases the environmental load of pathogens; this increases the risk for spreading diseases to people and animals. 相似文献
215.
Mercury emissions to the atmosphere from anthropogenic sources in Europe in 2000 and their scenarios until 2020 总被引:1,自引:0,他引:1
Pacyna EG Pacyna JM Fudala J Strzelecka-Jastrzab E Hlawiczka S Panasiuk D 《The Science of the total environment》2006,370(1):147-156
The paper reviews the current state of knowledge regarding European emissions of mercury and presents estimates of European emissions of mercury to the atmosphere from anthropogenic sources for the year 2000. This information was then used as a basis for Hg emission scenario development until the year 2020. Combustion of coal in power plants and residential heat furnaces generates about half of the European emissions being 239 tonnes. The coal combustion is followed by the production of caustic soda with the use of the Hg cell process (17%). Major points of mercury emission generation in the mercury cell process include: by-product hydrogen stream, end box ventilation air, and cell room ventilation air. This technology is now being changed to other caustic soda production technologies and further reduction of Hg emissions is expected in this connection. The third category on the list of the largest Hg emitters in Europe is cement production (about 13%). The largest emissions were estimated for Russia (the European part of the country), contributing with about 27% to the European emissions, followed by Poland, Germany, Spain, Ukraine, France, Italy and the United Kingdom. Most of these countries use coal as a major source of energy in order to meet the electricity and heat demands. In general, countries in the Central and Eastern Europe generated the main part of the European emissions in 2000. Emission reductions between 20% and 80% of the 2000 emission amounts can be obtained by the year 2020, as estimated by various scenarios. 相似文献
216.
1 INTRODUCTIONSkeletalreconstructionorregenerationisre quiredincasesinvolvinglargedefectscreatedbytu morresection ,trauma ,andskeletalabnormalities .Graftsandflapsofautogenoustissuearetwoofthemostsuccessfulmeansofreconstructionbecausetheyallowthetransplantationofbonecontainingbioactivemolecules,livecells ,andfrequently ,avascularsup plythatallowthetransplanttosurviveandremodeleveninhostileradiatedenvironments .However ,onlyaminimalamountoftissuecanbeharvestedforauto grafts,anditisverydiff… 相似文献
217.
Günter Mistlberger Klaus Koren Elisabeth Scheucher Daniel Aigner Sergey M. Borisov Armin Zankel Peter Pölt Ingo Klimant 《Advanced functional materials》2010,20(11):1842-1851
Magnetic optical sensor particles with multifunctional cores and shells are synthesized via a facile nanoprecipitation method and the subsequent modification of the particle shell. The hydrophobic particle core includes optical oxygen indicators, a light harvesting system, photosensitizers, and magnetic nanoparticles. Further functionalities are introduced by modifying the shell with enzymes, antibodies, multiple layers of polyelectrolytes, stimuli‐responsive polymers, and luminescent indicator dyes. The hydrodynamic diameter is tunable by varying different precipitation parameters. 相似文献
218.
219.
Elisabeth Wisker und Walter Feldheim 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1984,179(4):333-340
Zusammenfassung Der Ballaststoffgehalt verschiedener Brote wird nach zwei Methoden bestimmt. Mit der modifizierten Neutraldetergentien-Methode werden durchschnittlich 60% der enzymatisch-chemisch bestimmbaren Ballaststoffe erfaßt. Für die Bestimmung des Brennwertes werden die Hauptinhaltsstoffe analytisch bestimmt, die verwertbaren Kohlenhydrate werden zusätzlich nach verschiedenen Verfahren durch Differenz berechnet. Der Energiegehalt wird mit den allgemeinen Atwater-Faktoren (4/9/4), spezifischen Faktoren und mit den physikalischen Brennwerten der resorbierbaren Nährstoffe berechnet.
The effect of methods used for the determination of dietary fiber and available carbohydrates on the calculation of the physiological fuel value of breads
Summary The dietary fiber content of German breads was determined by two different methods. With a modified NDF-method 60% of total dietary fiber (determined by an enzymatic-chemical procedure) are detected. For estimation of the physiological fuel value the main components of breads were determined by analysis. In addition, the carbohydrates were determined by difference, using various methods of calculation. For the estimation of the caloric value, different calorie conversion factors are used.相似文献
220.
Elisabeth Wisker Martina Daniel Walter Feldheim 《Journal of the science of food and agriculture》1996,70(3):327-333
The effect of particle size of whole meal rye bread on the apparent digestibility of macro-nutrients, non-starch polysaccharides (NSP) and energy, the energy value of rye NSP and on faecal weight was studied in balance experiments in seven young women. The whole meal breads were prepared from one single batch of rye milled to two different particle sizes (coarse bread: 50% of particles >2 mm, 90% >1 mm; fine bread: 86% of particles <0·5 mm, 58% <0·2 mm). Two diets containing either coarse (350 g day−1) or fine (377 g day−1) whole meal bread and a low fibre control diet were consumed for 3 weeks each in a 3×3 cross-over design. Relative to the low fibre control diet, digestibility of protein, NSP and energy was significantly lower for the diets containing the whole meal breads. Digestibility of fat was the same for all diets. Partial digestible energy value for each g of NSP from coarse and fine whole meal rye bread was calculated to be −3±7 and 1±5 kJ, respectively. There were no differences between coarse and fine whole meal rye bread in the effects on the parameters measured with the exception on faecal wet weight, which was higher for the coarse bread diet. 相似文献