TY - JOUR A1 - Bleck, W. A1 - Bork, Claus-Peter A1 - Evertz, Th. A1 - Frehn, A. A1 - Masendorf, R. A1 - Sonsino, C.M. A1 - Steinbeck, G. T1 - Ermittlung von Berechnungskennwerten an Karosseriestählen N2 - In einem Gemeinschaftsprojekt der Stahl- und Automobilindustrie wurden an zwanzig Stählen für Feinblech elastische, plastische und zyklische Kennwerte für die FE-Simulation ermittelt. Die Untersuchungen mit dem Ziel, Eingabekennwerte für FE-Berechnungen zu erhalten, erbrachten einen erheblichen Erfahrungszuwachs im Bereich der Messtechnik sowie der Datenerfassung und -weiterverarbeitung. Der vorliegende Beitrag gibt einen Überblick über die Untersuchung und ihre Ergebnisse. KW - Feinblech Stähle KW - Kennwerte für die FEM-Simulation KW - Elastisch KW - Plastisch KW - Zyklisch KW - Standardisierte Kennwertermittlung KW - Rechnerisch PY - 2005 SN - 0001-2785 VL - 107 IS - 5 SP - 436 EP - 447 PB - Vieweg CY - Wiesbaden AN - OPUS4-10654 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Menrad, Andreas A1 - Goedecke, Thomas A1 - Gründer, Klaus-Peter A1 - Wagner, M.H. T1 - The internal pressure test in experiment and simulation - Influence of the wall thickness variation and the change of the packaging behavior after the impact of standard liquids N2 - The effect of the wall thickness variation of blow-moulded bodies made of high-density polyethylene on an internal pressure test after prestoring the packaging with standard liquids was evaluated in experiments and simulations. The objects of the investigation were jerrycans used for the transportation and storage of dangerous goods. The wall thickness was determined using two alternative methods to the magnetostatic measurement. These alternative methods are used for research purpose to get a volumetric model of the jerrycan wall as a geometric model for the simulation. The comparison of the experiments and the simulations of the internal pressure test were performed using the digital image correlation method. The integral strain and deformation of the whole jerrycan was detected by measuring the total mass of the jerrycan being filled with water during the internal pressure test. This is a suitable alternative to the optical measurements of local deformation by the digital image correlation method. Prestorage at 40°C without the influence of chemicals strengthens the jerrycan, whereas the swelling effect of butyl acetate and hydrocarbon mixture softens the jerrycan. The comparison with the experiment is necessary to verify the accuracy of the simulation. It shows that the deformation can be simulated more precisely by using the actual measured geometry. The weakening of the high-density polyethylene caused by a hydrocarbon mixture can be simulated using the Arrhenius equation. The aim of the simulation was to discover whether it is possible to use specimens to predict the behaviour of a packaging both after the influence of standard liquids. T2 - 18th IAPRI World packaging conference CY - San Luis Obispo, CA, USA DA - 17.06.2012 KW - Wall thickness KW - Internal pressure test KW - Finite element KW - Simulation KW - Jerrycan PY - 2013 DO - https://doi.org/10.1002/pts.1983 SN - 0894-3214 VL - 26 IS - 6 SP - 311 EP - 326 PB - Wiley CY - Chichester, UK AN - OPUS4-29282 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Steinbeck, G. A1 - Bleck, W. A1 - Bork, Claus-Peter A1 - Evertz, T. A1 - Frehn, A. A1 - Masendorf, R. A1 - Sonsino, C.M. ED - Palkowski, H. T1 - Ermittlung von Berechnungskennwerten an Karosseriestählen - Bericht über ein Gemeinschaftsprojekt der Stahl- und Automobilindustrie T2 - 4. Industriekolloquium - SFB 362 Fertigen in Feinblech - Werkstoffe Verfahren Konzepte CY - Bad Harzburg, Deutschland DA - 2004-02-11 KW - Karosseriestähle KW - Berechnung KW - Kennwerte PY - 2004 SN - 3937057056 VL - 1 IS - 2 SP - 127 EP - 136 PB - GRIPS media AN - OPUS4-22600 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Natsopoulou, M.E. A1 - McMahon, Dino Peter A1 - Doublet, V. A1 - Bryden, J. A1 - Paxton, R.J. T1 - Interspecific competition in honeybee intracellular gut parasites is asymmetric and favours the spread of an emerging infectious disease N2 - There is increasing appreciation that hosts in natural populations are subject to infection by multiple parasite species. Yet the epidemiological and ecological processes determining the outcome of mixed infections are poorly understood. Here, we use two intracellular gut parasites (Microsporidia), one exotic and one co-evolved in the western honeybee (Apis mellifera), in an experiment in which either one or both parasites were administered either simultaneously or sequentially. We provide clear evidence of within-host competition; order of infection was an important determinant of the competitive outcome between parasites, with the first parasite significantly inhibiting the growth of the second, regardless of species. However, the strength of this 'priority effect' was highly asymmetric, with the exotic Nosema ceranae exhibiting stronger inhibition of Nosema apis than vice versa. Our results reveal an unusual asymmetry in parasite competition that is dependent on order of infection. When incorporated into a mathematical model of disease prevalence, we find asymmetric competition to be an important predictor of the patterns of parasite prevalence found in nature. Our findings demonstrate the wider significance of complex multi-host–multi-parasite interactions as drivers of host–pathogen community structure. KW - Apis mellifera KW - Microsporidia KW - Host KW - Parasite KW - Co-infection KW - Priority effect PY - 2014 DO - https://doi.org/10.1098/rspb.2014.1896 SN - 1471-2954 SN - 0950-1193 SN - 0080-4649 SN - 0962-8452 VL - 282 SP - 20141896, 1 EP - 8 PB - Royal Soc. of London CY - London AN - OPUS4-32883 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mayack, C. A1 - Natsopoulou, M.E. A1 - McMahon, Dino Peter T1 - Nosema ceranae alters a highly conserved hormonal stress pathway in honeybees N2 - Nosema ceranae, an emerging pathogen of the western honeybee (Apis mellifera), is implicated in recent pollinator losses and causes severe energetic stress. However, whether precocious foraging and accelerated behavioural maturation in infected bees are caused by the infection itself or via indirect energetic stress remains unknown. Using a combination of nutritional and infection treatments, we investigated how starvation and infection alters the regulation of adipokinetic hormone (AKH) and octopamine, two highly conserved physiological pathways that respond to energetic stress by mobilizing fat stores and increasing search activity for food. Although there was no response from AKH when bees were experimentally infected with N. ceranae or starved, supporting the notion that honeybees have lost this pathway, there were significant regulatory changes in the octopamine pathway. Significantly, we found no evidence of acute energetic stress being the only cause of symptoms associated with N. ceranae infection. Therefore, the parasite itself appears to alter regulatory components along a highly conserved physiological pathway in an infection-specific manner. This indicates that pathogen-induced behavioural alteration of chronically infected bees should not just be viewed as a coincidental short-term by-product of pathogenesis (acute energetic stress) and may be a result of a generalist manipulation strategy to obtain energy for reproduction. KW - Octopamine KW - Adipokinetic hormone (AKH) KW - Apis mellifera KW - Energetic stress KW - Starvation KW - Hunger PY - 2015 DO - https://doi.org/10.1111/imb.12190 SN - 0962-1075 SN - 1365-2583 SP - 1 EP - 9 PB - Blackwell CY - Oxford AN - OPUS4-34168 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Natsopoulou, M.E. A1 - McMahon, Dino Peter A1 - Paxton, R.J. T1 - Parasites modulate within-colony activity and accelerate the temporal polyethism schedule of a social insect, the honey bee N2 - Task allocation in social insect colonies is generally organised into an age-related division of labour, termed the temporal polyethism schedule, which may in part have evolved to reduce infection of the colony's brood by pests and pathogens. The temporal polyethism schedule is sensitive to colony perturbations that may lead to adaptive changes in task allocation, maintaining colony homeostasis. Though social insects can be infected by a range of parasites, little is known of how these parasites impact within-colony behaviour and the temporal polyethism schedule. We use honey bees (Apis mellifera) experimentally infected by two of their emerging pathogens, Deformed wing virus (DWV), which is relatively understudied concerning its behavioural impact on its host, and the exotic microsporidian Nosema ceranae. We examined parasite effects on host temporal polyethism and patterns of activity within the colony. We found that pathogens accelerated the temporal polyethism schedule, but without reducing host behavioural repertoire. Infected hosts exhibited increased hyperactivity, allocating more time to self-grooming and foraging-related tasks. The strength of behavioural alterations we observed was found to be pathogen specific; behavioural modifications were more pronounced in virus-treated hosts versus N. ceranae-treated hosts, with potential benefits for the colony in terms of reducing within-colony transmission. Investigating the effects of multiple pathogens on behavioural patterns of social insects could play a crucial role in understanding pathogen spread within a colony and their effects on colony social organisation. KW - Host KW - Pathogen KW - Multiple infection KW - Apis mellifera KW - Nosema ceranae KW - Deformed wing virus PY - 2016 DO - https://doi.org/10.1007/s00265-015-2019-5 SN - 0340-5443 SN - 1432-0762 VL - 70 IS - 7 SP - 1019 EP - 1031 PB - Springer CY - Berlin ; Heidelberg [u.a.] AN - OPUS4-34738 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - McMahon, Dino Peter A1 - Wilfert, L. A1 - Paxton, R.J. A1 - Brown, M.J.F. T1 - Emerging viruses in bees: From molecules to ecology N2 - Emerging infectious diseases arise as a result of novel interactions between populations of hosts and pathogens, and can threaten the health and wellbeing of the entire spectrum of biodiversity. Bees andtheir viruses area case in point. However, detailed knowledge of the ecological factors and evolutionary forces that drive disease emergence in bees and other host–pathogen communities is surprisingly lacking. In this review, we build on the fundamental insight that viruses evolve and adapt over timescales that overlap with host ecology. At the same time, we integrate the role of host community ecology, including community structure and composition, biodiversity loss, and human driven disturbance, all of which represent significant factors in bee virus ecology. Both of these evolutionary and ecological perspectives represent major advances but, in most cases, it remains unclear how evolutionary forces actually operate across different biological scales (e.g., from cell to ecosystem). We present a molecule-to-ecology framework to help address these issues, emphasizing the role of molecular mechanisms as keybottom-up drivers of change at higher ecological scales. We consider the bee–virus system to be an ideal one in which to apply this framework. Unlike many other animal models, bees constitute a well characterized and accessible multispecies assemblage, whose populations and interspecific interactions can be experimentally manipulated and monitored in high resolution across space and time to provide robust tests of prevailing theory. KW - Emerging KW - Virus KW - Pathogen KW - Bee KW - Disease PY - 2018 DO - https://doi.org/10.1016/bs.aivir.2018.02.008 SN - 0065-3527 VL - 101 SP - 251 EP - 291 AN - OPUS4-46324 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -