Gegenzbiete der Lebensmittelwissenschaft

Ohne Zusammenfassung     

Copolymers from 1-phenyl-2-(3-vinylphenylthio)-diazen and styrene and grafting with acrylonitrile

Summary A new azo monomer (2) was synthesized and copolymerized with styrene. The resulting azo copolymer could be used as an initiator for the acrylonitrile polymerisation yielding grafted copolymers. Quantitative treatment of the grafting experiments leads to the conclusion that the intermediate thiyl radicals show less reactivity towards monomers than phenyl radicals.     

Messung der Druckverteilung beim Hohlzug von Rohren und beim Ziehen von Rundstäben

Messung mit durchgehenden Druckstiften und Messung der Durchwölbung membranartiger Meßstellen in der Ziehholwand. Ziehversuche an Rohren ohne Innenwerkzeug im gesamten Bereich des Wanddicken-Durchmesser-Verhältnisses unter Einschluß des Stabes als Gremfall. Einfluß der Umformbedingungen auf den Druckverlauf. Berechnung des Reibungsbeiwertes aus den gemessenen Drücken und Ziehkräften. Vergleich des Druckverlaufs beim Ziehen und Einstoßen.     

Impact of lean interventions on time buffer reduction in a hospital setting

This paper focuses on performance changes stemming from a series of lean interventions in a medical laboratory. This research is one of the first to link a series of lean interventions and performance over time. In a mixed-method case study, six years of patient-related throughput data, retrieved from a laboratory computer database, are analysed. Three distinct periods with significant differences in throughput time performance can be distinguished. Semi-structured interviews were held to investigate the lean interventions preceding the performance changes. Given the long-term nature of the study, the event history calendar method was applied to enhance the respondents’ recall and reliability. A single lean intervention, among the hundreds that took place, was supposed to cause the main reduction in throughput times. It concentrated on improving process flow through the removal of batching, a source of artificial variability. A later major intervention, the introduction of flow-focused machinery, had mixed effects and initial performance gains were not sustained. The results show that ongoing series of interventions do not always lead to ongoing performance improvements in terms of throughput times but support theories emphasising the importance of variability reduction.     

Flavonoids, sugars and fruit acids of alpine bearberry (Arctostaphylos alpina) from Finnish Lapland

Alpine bearberry (Arctostaphylos alpina L.) is a special circumpolar edible berry primarily used for household purposes but with greater potential in commercial applications than utilized thus far. In this study, the flavonoids of alpine bearberry were investigated with HPLC-DAD and HPLC-MS, and the sugars and fruit acids as trimethylsilyl derivates with GC-FID. The most abundant anthocyanin was cyanidin-3-O-galactoside accounting for over 95% of the anthocyanins. Eight other anthocyanins existed in trace amounts only, the richest of them being cyanidin-3-O-arabinoside and cyanidin-3-O-glucoside. Cyanidin accounted for over 99% of the anthocyanin aglycones. All the flavonols identified were glycosides of quercetin. Majority of the sugars were glucose and fructose while the most abundant fruit acid was quinic acid. The unique anthocyanin composition of alpine bearberry encourages advanced use of the berry as a food ingredient in private households and in industrial applications. In addition, it serves as a unique reference material for research purposes.     

Identifying the Molecular Mechanisms and Types of Cell Death Induced by bio- and pyr-Silica Nanoparticles in Endothelial Cells

The term “nanosilica” refers to materials containing ultrafine particles. They have gained a rapid increase in popularity in a variety of applications and in numerous aspects of human life. Due to their unique physicochemical properties, SiO₂ nanoparticles have attracted significant attention in the field of biomedicine. This study aimed to elucidate the mechanism underlying the cellular response to stress which is induced by the exposure of cells to both biogenic and pyrogenic silica nanoparticles and which may lead to their death. Both TEM and fluorescence microscopy investigations confirmed molecular changes in cells after treatment with silica nanoparticles. The cytotoxic activity of the compounds and intracellular RNS were determined in relation to HMEC-1 cells using the fluorimetric method. Apoptosis was quantified by microscopic assessment and by flow cytometry. Furthermore, the impact of nanosilica on cell migration and cell cycle arrest were determined. The obtained results compared the biological effects of mesoporous silica nanoparticles extracted from Urtica dioica L. and pyrogenic material and indicated that both types of NPs have an impact on RNS production causing apoptosis, necrosis, and autophagy. Although mesoporous silica nanoparticles did not cause cell cycle arrest, at the concentration of 50 μg/mL and higher they could disturb redox balance and stimulate cell migration.