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© 2016 European Association of Antennas and Propagation. This work considers a combined structural-electromagnetic analysis of large dish reflector antennas typically used in radio astronomy. The effect of gravitational deformation on the radio telescope is quantified by a structural analysis conducted with a finite element solver. The deformed geometry is then analysed using a computational electromagnetic package from which the performance degradation can be assessed. This offers key insights into the operation of the radio telescope under the influence of external forces, such as gravity.

Understanding the demographic history and genetic make-up of colonizing species is critical for inferring population sources and colonization routes. This is of main interest for designing accurate control measures in areas newly colonized by vector species of economically important pathogens. The biting midge Culicoides imicola is a major vector of orbiviruses to livestock. Historically, the distribution of this species was limited to the Afrotropical region. Entomological surveys first revealed the presence of C. imicola in the south of the Mediterranean basin by the 1970s. Following recurrent reports of massive bluetongue outbreaks since the 1990s, the presence of the species was confirmed in northern areas. In this study, we addressed the chronology and processes of C. imicola colonization in the Mediterranean basin. We characterized the genetic structure of its populations across Mediterranean and African regions using both mitochondrial and nuclear markers, and combined phylogeographical analyses with population genetics and approximate Bayesian computation. We found a west/east genetic differentiation between populations, occurring both within Africa and within the Mediterranean basin. We demonstrated that three of these groups had experienced demographic expansions in the Pleistocene, probably because of climate changes during this period. Finally, we showed that C. imicola could have colonized the Mediterranean basin in the Late Pleistocene or Early Holocene through a single event of introduction; however, we cannot exclude the hypothesis involving two routes of colonization. Thus, the recent bluetongue outbreaks are not linked to C. imicola colonization event, but rather to biological changes in the vector or the virus.

Contains fulltext : 154023.pdf (Publisher’s version ) (Closed access), Subcellular partitioning of creatine kinase contributes to the formation of patterns in intracellular ATP distribution and the fuelling of cellular processes with a high and sudden energy demand. We have previously shown that brain-type creatine kinase (CK-B) accumulates at the phagocytic cup in macrophages where it is involved in the compartmentalized generation of ATP for actin remodeling. Here, we report that CK-B catalytic activity also helps in the formation of protrusive ruffle structures which are actin-dependent and abundant on the surface of both unstimulated and LPS-activated macrophages. Recruitment of CK-B to these structures occurred transiently and inhibition of the enzyme's catalytic activity with cyclocreatine led to a general smoothening of surface morphology as visualized by scanning electron microscopy. Comparison of the dynamics of distribution of YFP-tagged CK-mutants and isoforms by live imaging revealed that amino acid residues in the C-terminal segment (aa positions 323-330) that forms one of the protein's two mobile loops are involved in partitioning over inner regions of the cytosol and nearby sites where membrane protrusions occur during induction of phagocytic cup formation. Although wt CK-B, muscle-type CK (CK-M), and a catalytically dead CK-B-E232Q mutant with intact loop region were normally recruited from the cytosolic pool, no dynamic transition to the phagocytic cup area was seen for the CK-homologue arginine kinase and a CK-B-D326A mutant protein. Bioinformatics analysis helped us to predict that conformational flexibility of the C-terminal loop, independent of conformational changes induced by substrate binding or catalytic activity, is likely involved in exposing the enzyme for binding at or near the sites of membrane protrusion formation.

Contains fulltext : 135974.pdf (publisher's version ) (Open Access), Functional morphodynamic behavior of differentiated macrophages is strongly controlled by actin cytoskeleton rearrangements, a process in which also metabolic cofactors ATP and NAD(H) (i.e. NAD+ and NADH) and NADP(H) (i.e. NADP+ and NADPH) play an essential role. Whereas the link to intracellular ATP availability has been studied extensively, much less is known about the relationship between actin cytoskeleton dynamics and intracellular redox state and NAD+-supply. Here, we focus on the role of nicotinamide phosphoribosyltransferase (NAMPT), found in extracellular form as a cytokine and growth factor, and in intracellular form as one of the key enzymes for the production of NAD+ in macrophages. Inhibition of NAD+ salvage synthesis by the NAMPT-specific drug FK866 caused a decrease in cytosolic NAD+ levels in RAW 264.7 and Maf-DKO macrophages and led to significant downregulation of the glycolytic flux without directly affecting cell viability, proliferation, ATP production capacity or mitochondrial respiratory activity. Concomitant with these differential metabolic changes, the capacity for phagocytic ingestion of particles and also substrate adhesion of macrophages were altered. Depletion of cytoplasmic NAD+ induced cell-morphological changes and impaired early adhesion in phagocytosis of zymosan particles as well as spreading performance. Restoration of NAD+ levels by NAD+, NMN, or NADP+ supplementation reversed the inhibitory effects of FK866. We conclude that direct coupling to local, actin-based, cytoskeletal dynamics is an important aspect of NAD+'s cytosolic role in the regulation of morphofunctional characteristics of macrophages.

English: Culicoides midges are involved in the transmission of a variety of pathogens, the most economically important of these are the orbiviruses that cause African horse sickness (AHSV) and bluetongue (BTV). The identification of vectors of these viruses and monitoring of their occurrence and activity plays an important role in the control measures and disease risk analysis. The primary tool used for monitoring these midges through collection is various models of light traps. In order to standardise collection data to be comparable between laboratories, a variety of factors that affect the light trap collections were assessed. Comparisons of different light traps (Onderstepoort trap and the Free State trap), the influence of light colour, trapping height and the distance a trap is operated from the host animals were assessed. Comparisons were done using either three replicates of a 4 x 4 or two replicates of a 6 x 6 randomised Latin square design. The most significant variables were the trap type, with the Onderstepoort trap collecting significantly more Culicoides than the Free State trap, and the sampling distance from the host animals. The proportion of C. imicola (the most frequent species collected) was the highest when collected right next to host animals and decreased rapidly as collections moved further from host animals. Trap height also proved to be an important variable, although no significant differences were observed when collecting midges at two metres to three metres above the ground. The occurrence, abundance and seasonality of the midges frequenting livestock in the central Free State were also assessed by collecting midges using light traps over a four-year period from April 2007 up to May 2010. Twenty Culicoides species were collected, the most abundant and important species was C. imicola, a confirmed vector of both the AHSV and BTV. The midges showed a distinct seasonal pattern, but were also collected year round, identifying periods of high, Afrikaans: Culicoides muggies is betrokke by die verspreiding van ‘n verskeidenheid patogene, die van meeste ekonomiese belang is behoort aan die familie orbivirusse wat insluit die virusse wat Afrika perdesiekte (AHS) en Bloutong (BT) veroorsaak. Die identifisering van die vektore van die virusse en die monitering van hulle voorkoms en aktiwiteit speel ‘n belangrike rol in die beheer maatreëls en siekte risiko analises. Die primêre monitering van die muggies geskied deur middel van verskeie variasies ligvalle wat opgesit word naby gasheer diere en deur die nag muggies versamel. Om die ligval versameling te standariseer en die data van verskillende areas en versameling vergelykbaar te maak is ‘n reeks veranderlikes vergelyk. Vergelykings van verskillende ligvalle (Onderstepoort ligval en die Vrystaat ligval), die invloed van ligval kleur, ligval hoogte en die afstand wat ligvalle vanaf die naaste gasheer diere is vergelyk. Vergelykings is gedoen deur middel van die gebruik van drie herhalings van 4 x 4, of twee herhaling van 6 x 6 ewekansige latynse vierkant ontwerp. Die mees beduidende invloed was die soort ligval. Die Onderstepoort ligval het beduidend meer Culicoides muggies versamel as die nuut ontwikkelde Vrystaat ligval. Die afstand van die naaste gasheer dier het ook ‘n beduidende invloed op die muggie getalle gehad. Die proporsie C. imicola (die volopste spesie versamel) was die hoogste as die ligval reg langs die gasheer diere opgesit is en het baie vining verlaag soos die versamelings verder van die gasheer diere af weg gemaak is. Die ligval hoogte het ook ‘n beduidende invloed gehad: meer C. imicola is versamel van twee to drie meter bo die grond as by een en ‘n halwe meter hoog. Die voorkoms, volopheid en seisoenaliteit van die Culicoides muggies wat gasheer diere besoek in die sentrale Vrystaat is bepaal deur monitoring met ligvalle oor ‘n vier jaar periode vanaf April 2007 tot en met Mei 2010. Twintig spesies van Culicoides muggies is versamel, waarvan

Academics are divided as to whether financial risk tolerance is an enduring psychological trait and as a consequence is less likely to change over the life of an individual, or a variable psychological state which varies readily in response to internal and external influences. In this study we report the findings of a longitudinal study that investigates the annual change in financial risk tolerance scores of individuals over a 5. year period and the factors that influence such change. Our results indicate a relatively small annual change in individuals' financial risk tolerance. Although our regression model is ineffective in providing a clarification for a change in the financial risk tolerance scores of individual respondents, we find a slight decrease in financial risk tolerance associated with a decrease in household size and an increase in financial risk tolerance after terminating the services of a financial planner. From our results we propose that financial risk tolerance is a stable personality trait and is unlikely to change substantially over the life of an individual. © 2012 Elsevier B.V.

Financial market participants exercise judgment in decision making and psychological studies have shown that individuals are overconfident about their ability to evaluate financial securities. Range estimation calibration studies indicate that individuals tend to estimate narrow intervals in their estimation of unknown future quantities, suggesting overconfidence. Financial planners have an inherent duty of care and this may lead these individuals to behave differently in their estimation methodology and behaviour. From a survey of Australian financial planners, we find extensive overconfidence in respondents’ ability to make judgements under uncertainty as shown by a narrow range of forecasts and a substantial number of inaccurate predictions. The overconfidence is present both when comparing estimates to the ex-post outcome of a predicted quantity and to an interval based on historical return volatility. © 2008, SAGE Publications. All rights reserved.