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11.
Brietzke Adrian Pham Xuan Rebecca Dettmann André Bullinger Angelika C. 《Forschung im Ingenieurwesen》2021,85(2):517-526
Forschung im Ingenieurwesen - The enjoyment and usage of highly automated vehicles might be reduced by motion sickness. This study addresses the influencing factors of dynamic stimulation, visual... 相似文献
12.
Angelika Zimmermann Ilan Oshri Eleni Lioliou Alexandra Gerbasi 《The Journal of Strategic Information Systems》2018,27(1):82-100
The sharing of knowledge between a firm and its internal or external service suppliers has become an important element of contemporary sourcing arrangements. Moreover, the knowledge based view (KBV) has long suggested that due to stronger cognitive links within firms, internal compared to external service provision creates better conditions for knowledge sharing. Empirical evidence for this claim is however scarce, and the KBV does not explain the mechanisms for more knowledge sharing in internal sourcing in detail. Moreover, there is now some evidence to suggest that firms’ relationships with external sourcing partners are becoming more similar to those with captive centres, which represent a less traditional form of insourcing setting. To scrutinize the possible knowledge sharing advantages of internal sourcing in more depth, we turn to social capital (SC) research. There are some theoretical claims that SC and knowledge sharing are stronger within than between firms, and there is ample evidence that SC facilitates knowledge sharing. Our survey results suggest that the extent of knowledge sharing and SC are indeed stronger in a captive than in an external sourcing mode, and that structural (tie strength), cognitive (shared understanding), and relational (trust) aspects of SC mediate the effect of sourcing mode on the extent of knowledge sharing. By contrast, network stability (a structural aspect) mediated knowledge sharing only indirectly, by reinforcing the other SC aspects. We highlight important contributions to research and practice of IS outsourcing and social capital. 相似文献
13.
Johannes Kahl Nicolaas Busscher Wolfgang Hoffmann Gaby Mergardt Ingrid Clawin-Raedecker Christian Kiesner Angelika Ploeger 《Food Analytical Methods》2014,7(7):1373-1380
Crystallization with additives is developed on milk samples from different processing treatments. Performance tests are carried out based on structure analysis of the crystallization patterns. Crystallization with milk as additive is applied following changes in milk after different processing treatments. When an aqueous cupric chloride dihydrate solution crystallizes in the presence of milk as additive, specific patterns emerge, which can be evaluated by image analysis. Milk samples were heated and homogenized in a pilot plant and characterized by various parameters. Furthermore, milk samples from the market were tested. Patterns from milk after heat treatment and homogenization are significantly different from those derived from untreated milk. The experiments could be reproduced for other milk samples, on different days and in another laboratory. 相似文献
14.
Helmut Brandl Claudia Fricker-Feer Dominik Ziegler Jyotshna Mandal Roger Stephan Angelika Lehner 《Journal of dairy science》2014
Airborne communities (mainly bacteria) were sampled and characterized (concentration levels and diversity) at 1 outdoor and 6 indoor sites within a Swiss dairy production facility. Air samples were collected on 2 sampling dates in different seasons, one in February and one in July 2012 using impaction bioaerosol samplers. After cultivation, isolates were identified by mass spectrometry (matrix-assisted laser desorption/ionization-time-of-flight) and molecular (sequencing of 16S rRNA and rpoB genes) methods. In general, total airborne particle loads and total bacterial counts were higher in winter than in summer, but remained constant within each indoor sampling site at both sampling times (February and July). Bacterial numbers were generally very low (<100 cfu/m3 of air) during the different steps of milk powder production. Elevated bacterial concentrations (with mean values of 391 ± 142 and 179 ± 33 cfu/m3 of air during winter and summer sampling, respectively; n = 15) occurred mainly in the “logistics area,” where products in closed tins are packed in secondary packaging material and prepared for shipping. However, total bacterial counts at the outdoor site varied, with a 5- to 6-fold higher concentration observed in winter compared with summer. Twenty-five gram-positive and gram-negative genera were identified as part of the airborne microflora, with Bacillus and Staphylococcus being the most frequent genera identified. Overall, the culturable microflora community showed a composition typical and representative for the specific location. Bacterial counts were highly correlated with total airborne particles in the size range 1 to 5 µm, indicating that a simple surveillance system based upon counting of airborne particles could be implemented. The data generated in this study could be used to evaluate the effectiveness of the dairy plant’s sanitation program and to identify potential sources of airborne contamination, resulting in increased food safety. 相似文献
15.
Susanne Neugart Hans-Peter Kläring Michaela Zietz Monika Schreiner Sascha Rohn Lothar W. Kroh Angelika Krumbein 《Food chemistry》2012
The winter crop kale has a complex profile of different glycosylated and acylated flavonol glycosides which may be affected by global warming. To the best of our knowledge, compound–climate relationships for flavonol aglycones and flavonol glycosides were established for the first time. The investigated 10 major flavonol glycosides responded structure-dependent in the investigated temperature range between 0 and 12 °C and the photosynthetic active radiation range between 4 and 20 mol m−2 d−1, e.g. the decrease in temperature led to an increase in sinapic acid monoacylated and diacylated quercetin glycosides, while the sinapic acid monoacylated kaempferol glycosides showed a maximum at 4.5 °C. Furthermore, the hydroxycinnamic acid residues and the different number of glucose moieties in the 7-O position affected the response of kaempferol triglucosides. Consequently, global warming would result in lower concentrations of antioxidant-relevant quercetin glycosides in winter crops, suggesting a production at e.g. higher altitudes due to lower temperature. 相似文献
16.
Christian Pahl Eberhard Hartung Anne Grothmann Katrin Mahlkow-Nerge Angelika Haeussermann 《Journal of dairy science》2014
Monitoring rumination behavior serves multiple purposes in feeding and herd management of dairy cows. The process of calving is a major event for cows, and a detailed understanding of alterations in behavioral patterns of animals in the time around calving is important in calving detection. The objective of this study was to describe the short-term changes in rumination patterns in dairy cows immediately before and after parturition. In total, 17 cows were fitted with rumination sensors that were able to monitor rumination time, number of rumination boli, and number of rumination jaw movements. Rumination time was decreased in the last 4 h antepartum and in the first 8 h postpartum. Cows stopped ruminating 123 ± 58 min (mean ± standard deviation) before calving and resumed ruminating 355 ± 194 min after calving. The number of rumination jaw movements and boli per day were decreased in the 24-h period postpartum. Rumination rate, the number of rumination jaw movements per rumination minute, and the number of boli per rumination minute changed little around calving. The calving event primarily influenced the duration and frequency of various rumination characteristics but not rumination intensity. Among detected characteristics, rumination time showed the greatest potential for monitoring of calving events. 相似文献
17.
Malgorzata Wachowska Alicja Wojciechowska Angelika Muchowicz 《International journal of molecular sciences》2022,23(1)
Tumor-associated neutrophils appear to be a crucial element of the tumor microenvironment that actively participates in the development and progression of cancerous diseases. The increased lifespan, plasticity in changing of phenotype, and functions of neutrophils influence the course of the disease and may significantly affect survival. In patients with chronic lymphocytic leukemia (CLL), disturbances in neutrophils functions impede the effective immune defense against pathogens. Therefore, understanding the mechanism underlying such a phenomenon in CLL seems to be of great importance. Here we discuss the recent reports analyzing the phenotype and functions of neutrophils in CLL, the most common leukemia in adults. We summarize the data concerning both the phenotype and the mechanisms by which neutrophils directly support the proliferation and survival of malignant B cells. 相似文献
18.
Piotr Długosz Angelika Rączka Adrian Kopeć Rudolf Krzyżak Paweł Darłak Marek Hebda 《Journal of Materials Engineering and Performance》2016,25(6):2261-2266
This paper presents novel opportunities for management of fly ash by synthesizing the material into cordierite ceramics and using it as a reinforcing phase for light metal alloys. Metal matrix composites (based on magnesium alloy and aluminum alloy) were produced by squeeze casting. The magnesium matrix composites with a suitably selected reinforcing phase content (2 wt.%) exhibited much better strength properties than the unmodified alloy (AM60). It was also demonstrated that the wettability (or the lack thereof) in the metal-ceramic system is critical to successful production of the composites based on the AK7 alloy with cordierite. Light alloy matrix composites reinforced with cordierite ceramics particles are innovative materials that combine high strength with low weight, which may be a key factor of merit for numerous applications of the composite in various branches of industries. 相似文献
19.
In this work Substrate Induced Coagulation (SIC) was used to coat the cathode material LiCoO2, commonly used in Li-ion batteries, with fine nano-sized particulate titania. Substrate Induced Coagulation is a self-assembled dip-coating process capable of coating different surfaces with fine particulate materials from liquid media. A SIC coating consists of thin and rinse-prove layers of solid particles. An advantage of this dip-coating method is that the method is easy and cheap and that the materials can be handled by standard lab equipment. Here, the SIC coating of titania on LiCoO2 is followed by a solid-state reaction forming new inorganic layers and a core-shell material, while keeping the content of active battery material high. This titania based coating was designed to confine the reaction of extensively delithiated (charged) LiCoO2 and the electrolyte. The core-shell materials were characterized by SEM, XPS, XRD and Rietveld analysis. 相似文献
20.
The determination of pesticide residues in food matrices is a formidable challenge mainly because of the small quantities of analytes and large amounts of interfering substances which can be co-extracted with analytes and, in most cases, adversely affect the results of an analysis. However, safety concerns require that pesticides of the wide range of chemical properties (including acidic, basic and neutral) should be monitored. Because of the wide variety of food matrices, the sample must initially be cleaned up before final analysis. That is why the analytical chemist is faced with the need to devise new methodologies for determining such residues to be determined in a single analytical run. To accomplish the goal, QuEChERS methodology has been developed. It is a streamlined and effective extraction and cleanup approach for the analysis of diverse analyte residues in food matrices. So far, there have been achieved promising results by liquid or gas chromatography analysis, including pesticides, but also acrylamide, pharmaceuticals and veterinary drugs. 相似文献