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61.
Christoph Thurm Burkhart Schraven Sascha Kahlfuss 《International journal of molecular sciences》2021,22(17)
ATP-binding cassette (ABC) transporters represent a heterogeneous group of ATP-dependent transport proteins, which facilitate the import and/or export of various substrates, including lipids, sugars, amino acids and peptides, ions, and drugs. ABC transporters are involved in a variety of physiological processes in different human tissues. More recent studies have demonstrated that ABC transporters also regulate the development and function of different T cell populations, such as thymocytes, Natural Killer T cells, CD8+ T cells, and CD4+ T helper cells, including regulatory T cells. Here, we review the current knowledge on ABC transporters in these T cell populations by summarizing how ABC transporters regulate the function of the individual cell types and how this affects the immunity to viruses and tumors, and the course of autoimmune diseases. Furthermore, we provide a perspective on how a better understanding of the function of ABC transporters in T cells might provide promising novel avenues for the therapy of autoimmunity and to improve immunity to infection and cancer. 相似文献
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Sascha Bach Karsten Thürling Jens‐Peter Majschak 《Packaging Technology and Science》2012,25(4):233-248
The closure process for packaging is a key process. It ensures the protective function of packaging and assures the packaged goods a long life. In this context, efficient and reliable sealing processes are essential for the production of sustainable packages. In this paper, several characteristics of the ultrasonic sealing process will be discussed and accompanied by experimental results. The introduction provides an insight into the ultrasonic sealing process, its heating mechanisms and the process steps. A comparison is made with conduction sealing. Furthermore, basic principles of heating and energy dissipation are related to the influences of the sealing parameters on the seam strength. The experimental studies were carried out on typical packaging films, such as polyamide‐polyethylene laminates. The seam strength in ultrasonic sealing is compared with that in conductive sealing. A lower seam strength was found for ultrasonic sealing in all the tested films. Furthermore, the sealing behaviour of the packaging films contaminated with different kinds of foods was analysed for both sealing methods. Although the ultrasonic sealing method has marginal advantages for bulk materials such as wheat flour, conduction sealing was shown to be better for other products. A comparison of the energy consumption during the ultrasonic and conduction sealing verified the advantages of ultrasonic sealing. In particular for thick packaging films, the amount of energy required for bonding is significantly lower than for conduction sealing. In summary, this paper provides a survey of the characteristics of the ultrasonic sealing method in packaging applications – its advantages and limitations. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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Conrad Markus; Carreiras Manuel; Tamm Sascha; Jacobs Arthur M. 《Canadian Metallurgical Quarterly》2009,35(2):461
Over the last decade, there has been increasing evidence for syllabic processing during visual word recognition. If syllabic effects prove to be independent from orthographic redundancy, this would seriously challenge the ability of current computational models to account for the processing of polysyllabic words. Three experiments are presented to disentangle effects of the frequency of syllabic units and orthographic segments in lexical decision. In Experiment 1 the authors obtained an inhibitory syllable frequency effect that was unaffected by the presence or absence of a bigram trough at the syllable boundary. In Experiments 2 and 3 an inhibitory effect of initial syllable frequency but a facilitative effect of initial bigram frequency emerged when manipulating 1 of the 2 measures and controlling for the other in Spanish words starting with consonant-vowel syllables. The authors conclude that effects of syllable frequency and letter-cluster frequency are independent and arise at different processing levels of visual word recognition. Results are discussed within the framework of an interactive activation model of visual word recognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Numerical simulation of pile driving in the area of soil resistance of pit walls. In‐situ measurements at deep excavations during the construction show that the installation of buoyancy piles for the pit floor leads to large deformations of the pit walls. Today these additional loads caused by the construction of adjacent piles cannot be predicted and often lead to astonishment. The aim of this article is to present a first numerical model to predict the additional loads for the ground and the pit walls in the near field of driven piles. Regarding additional deformations of a pit wall at the Potsdamer Platz due to vibratory pile driving of buoyancy piles the importance of the numerical investigation is described. Nevertheless in the future considerable efforts are necessary to receive recommendations for the construction of pit walls. 相似文献
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Eduardo Weingärtner Sascha Jaumann Friedrich Kuster Konrad Wegener 《The International Journal of Advanced Manufacturing Technology》2010,48(9-12):1001-1007
Traditional multivariate control charts such as Hotelling’s χ 2 and T 2 control charts are designed to monitor vectors of variable quality characteristics. However, in certain situations, data are expressed in linguistic terms and, under these circumstances, variable or attribute multivariate control charts are not suitable choices for monitoring purposes. Fuzzy multivariate control charts such as fuzzy Hotelling’s T 2 could be considered as efficient tools to overcome the problems of linguistic observations. The purpose of this paper is to develop a fuzzy multivariate exponentially weighted moving average (F-MEWMA) control chart. In this paper, multivariate statistical quality control and fuzzy set theory are combined to develop the proposed method. Fuzzy sets and fuzzy logic are powerful mathematical tools for modeling uncertain systems in industry, nature, and humanity. Through a numerical example, the performance of the proposed control chart was compared to the fuzzy Hotelling’s T 2 control chart. Results indicate uniformly superior performance of the F-MEWMA control chart over Hotelling’s T 2 control chart. 相似文献
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Mocker A Bugiel S Auer S Baust G Colette A Drake K Fiege K Grün E Heckmann F Helfert S Hillier J Kempf S Matt G Mellert T Munsat T Otto K Postberg F Röser HP Shu A Sternovsky Z Srama R 《The Review of scientific instruments》2011,82(9):095111
Investigating the dynamical and physical properties of cosmic dust can reveal a great deal of information about both the dust and its many sources. Over recent years, several spacecraft (e.g., Cassini, Stardust, Galileo, and Ulysses) have successfully characterised interstellar, interplanetary, and circumplanetary dust using a variety of techniques, including in situ analyses and sample return. Charge, mass, and velocity measurements of the dust are performed either directly (induced charge signals) or indirectly (mass and velocity from impact ionisation signals or crater morphology) and constrain the dynamical parameters of the dust grains. Dust compositional information may be obtained via either time-of-flight mass spectrometry of the impact plasma or direct sample return. The accurate and reliable interpretation of collected spacecraft data requires a comprehensive programme of terrestrial instrument calibration. This process involves accelerating suitable solar system analogue dust particles to hypervelocity speeds in the laboratory, an activity performed at the Max Planck Institut fu?r Kernphysik in Heidelberg, Germany. Here, a 2 MV Van de Graaff accelerator electrostatically accelerates charged micron and submicron-sized dust particles to speeds up to 80 km s(-1). Recent advances in dust production and processing have allowed solar system analogue dust particles (silicates and other minerals) to be coated with a thin conductive shell, enabling them to be charged and accelerated. Refinements and upgrades to the beam line instrumentation and electronics now allow for the reliable selection of particles at velocities of 1-80 km s(-1) and with diameters of between 0.05 μm and 5 μm. This ability to select particles for subsequent impact studies based on their charges, masses, or velocities is provided by a particle selection unit (PSU). The PSU contains a field programmable gate array, capable of monitoring in real time the particles' speeds and charges, and is controlled remotely by a custom, platform independent, software package. The new control instrumentation and electronics, together with the wide range of accelerable particle types, allow the controlled investigation of hypervelocity impact phenomena across a hitherto unobtainable range of impact parameters. 相似文献
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