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81.
Schnedl Wolfgang J. Schenk Michael Lackner Sonja Enko Dietmar Mangge Harald Forster Florian 《Food science and biotechnology》2019,28(6):1779-1784
Food Science and Biotechnology - Histamine intolerance (HIT) is thought to be caused by a disproportionate amount of histamine in the body. The enzyme diamine oxidase (DAO) is considered for the... 相似文献
82.
In this article, a new method for segmentation and restoration of images on two-dimensional surfaces is given. Active contour models for image segmentation are extended to images on surfaces. The evolving curves on the surfaces are mathematically described using a parametric approach. For image restoration, a diffusion equation with Neumann boundary conditions is solved in a postprocessing step in the individual regions. Numerical schemes are presented which allow to efficiently compute segmentations and denoised versions of images on surfaces. Also topology changes of the evolving curves are detected and performed using a fast sub-routine. Finally, several experiments are presented where the developed methods are applied on different artificial and real images defined on different surfaces. 相似文献
83.
Harald Pühringer Zeineb Nejim Michael Pfleger Stefan Katletz 《Journal of Infrared, Millimeter and Terahertz Waves》2016,37(2):123-127
A novel and continuous detection scheme for the pulse amplitude and temporal position of a terahertz time domain system is presented. Currently, we have achieved a sampling time of 25 Hz and a resolution of less than 70 fs. The method is therefore very well suited for online measurements in production processes to monitor the thickness and inhomogeneities in the composition of non-conducting materials. 相似文献
84.
Martin Stueckelschweiger Dietmar Gruber Shengli Jin Harald Harmuth 《Ceramics International》2019,45(8):9776-9781
Mechanical testing of carbon containing refractories at high temperatures requires measures to protect the sample from oxidation. Therefore, special setups for tensile and compressive creep testing were developed to prevent the oxidation of carbon in the sample. A MgO-C refractory was selected for a case study. These developments allow the quantification of the tensile and compressive creep behaviour of MgO-C refractories at temperatures up to 1500?°C. The creep parameters are determined by an inverse evaluation method for the obtained experimental data. They enable the consideration of creep in a thermomechanical finite element simulation of refractory linings in service. 相似文献
85.
Dr. Aline Telzerow Dr. Juraj Paris Dr. Maria Håkansson Dr. Javier González-Sabín Dr. Nicolas Ríos-Lombardía Prof. Dr. Harald Gröger Dr. Francisco Morís Dr. Martin Schürmann Prof. Dr. Helmut Schwab Dr. Kerstin Steiner 《Chembiochem : a European journal of chemical biology》2021,22(7):1232-1242
Amine transaminases (ATAs) are used to synthesize enantiomerically pure amines, which are building blocks for pharmaceuticals and agrochemicals. R-selective ATAs belong to the fold type IV PLP-dependent enzymes, and different sequence-, structure- and substrate scope-based features have been identified in the past decade. However, our knowledge is still restricted due to the limited number of characterized (R)-ATAs, with additional bias towards fungal origin. We aimed to expand the toolbox of (R)-ATAs and contribute to the understanding of this enzyme subfamily. We identified and characterized four new (R)-ATAs. The ATA from Exophiala sideris contains a motif characteristic for d -ATAs, which was previously believed to be a disqualifying factor for (R)-ATA activity. The crystal structure of the ATA from Shinella is the first from a Gram-negative bacterium. The ATAs from Pseudonocardia acaciae and Tetrasphaera japonica are the first characterized (R)-ATAs with a shortened/missing N-terminal helix. The active-site charges vary significantly between the new and known ATAs, correlating with their diverging substrate scope. 相似文献
86.
Jia Zhou Pei-Luen Patrick Rau Gavriel Salvendy 《Universal Access in the Information Society》2014,13(4):401-413
This study examined the difference between younger adults and older adults in requirements for mobile phones and acceptance of new functions. A survey was conducted among 351 older adults and 140 younger adults in China. Four major findings were derived. Firstly, older adults perceived ease to understand manuals, font size, icon size, and feedback of the operation as more important compared with younger adults. Secondly, younger adults placed more emphasis on most non-visual aspects of mobile phones than older adults, while older adults placed more emphasis on visible attributes. Thirdly, the biggest age-related difference lays in connectivity. Younger adults perceived Internet access and the connection between mobile phones and other devices as much more important compared with older adults. Fourthly, older adults had more difficulties using soft keys and multi-tap than younger adults, which implied that smart phones with changing button labels and the touch & hold operation would be confusing for older adults. These results were interpreted in the context of the transition from feature phones to smart phones. 相似文献
87.
N. S. Chilingarov A. V. Nikitin J. V. Rau L. N. Sidorov 《Fullerenes, Nanotubes and Carbon Nanostructures》2013,21(3):577-598
Abstract Fluorination of [60]fullerene and [60]fullerene-NiF2(s) has been studied in situ by Knudsen cell mass spectrometry with admission of molecular fluorine. The fluorination processes were controlled in the temperature range 500 ? 800 K at molecular fluorine pressure 10?4 ? 10?5 atm. Temperature, time of fluorination and fluorine pressure were varied during the investigation. It was found that variation of these parameters did not lead to the selective fluorination. It was shown that NiF2(s) significantly influences the composition of the product mixture: a large amount of nickel difluoride in the system suppresses the fluorination reaction while the presence of a small amount promotes the selective fluorination. C60Fi18 (50% in the gas phase) was produced in our experiments under the following conditions: 20 h, 720 K, P(F2) = 2 10?4 atm in the prefluorinated (inner surface covered with NiF2(s) layer) Ni-reactor. An important point of the study was verification of the thermodynamic equilibrium in the system. It was concluded that the equilibrium is not established in the system under study, and the fluorination is governed by kinetic factors. 相似文献
88.
Susanne Struck Doris Jaros Charles S. Brennan Harald Rohm 《International Journal of Food Science & Technology》2014,49(9):1963-1976
This review presents the state‐of‐the‐art concerning the application of natural and artificial high‐intensity sweeteners, fructans and bulking agents such as polyols as sugar replacers in sweet‐baked goods and their effects on product characteristics. The recent much publicised attention given to weight gain of the population and its consequences on the occurrence of diet‐related diseases in developed countries has influenced the food manufacturers attempts to provide the consumer with reduced energy products. The replacement of sucrose in sweet bakery products by alternative natural or artificial sweeteners can be a challenging issue. Sucrose as a main ingredient in sweet bakery products contributes, aside from providing sweetness, to numerous processing and product characteristics. Intense sweeteners have a high sweetness compared with sucrose but lack in their contribution to the body of the product, whereas the replacement of sucrose with bulking sweeteners may result in products with a similar body but a lack in taste and flavour. 相似文献
89.
90.
In this paper, we present a middleware platform that supports the dynamic evolution of distributed component-based systems. It leverages the concept of ontologies to model the context of a system and an intrinsic mechanism is integrated to causally connect the dynamic architecture specification to the running system implementation. The ontological modeling covers both the environmental and the architectural knowledge using semantic data modeling. The intrinsic mechanism can automatically derive a run-time polymorphic architecture object to coordinate the involved components. The ontology based contextual representation and the polymorphic architecture-driven dynamic evolution are the two underpinnings of the platform. A scenario application—including the two primitive evolution actions—with the performance analysis is discussed to illustrate the feasibility. 相似文献