Orientation cues for high-flying nocturnal insect migrants: do turbulence-induced temperature and velocity fluctuations indicate the mean wind flow?

Migratory insects flying at high altitude at night often show a degree of common alignment, sometimes with quite small angular dispersions around the mean. The observed orientation directions are often close to the downwind direction and this would seemingly be adaptive in that large insects could add their self-propelled speed to the wind speed, thus maximising their displacement in a given time. There are increasing indications that high-altitude orientation may be maintained by some intrinsic property of the wind rather than by visual perception of relative ground movement. Therefore, we first examined whether migrating insects could deduce the mean wind direction from the turbulent fluctuations in temperature. Within the atmospheric boundary-layer, temperature records show characteristic ramp-cliff structures, and insects flying downwind would move through these ramps whilst those flying crosswind would not. However, analysis of vertical-looking radar data on the common orientations of nocturnally migrating insects in the UK produced no evidence that the migrants actually use temperature ramps as orientation cues. This suggests that insects rely on turbulent velocity and acceleration cues, and refocuses attention on how these can be detected, especially as small-scale turbulence is usually held to be directionally invariant (isotropic). In the second part of the paper we present a theoretical analysis and simulations showing that velocity fluctuations and accelerations felt by an insect are predicted to be anisotropic even when the small-scale turbulence (measured at a fixed point or along the trajectory of a fluid-particle) is isotropic. Our results thus provide further evidence that insects do indeed use turbulent velocity and acceleration cues as indicators of the mean wind direction

Konsumentenbefragung zu zertifizierten nachhaltigen Lebensmitteln – Die Bedeutung von Fairtrade und Bio

An den wirtschaftswissenschaftlichen Fakultäten der Technischen Hochschule Köln (TH Köln) und der Hochschule Bonn-Rhein-Sieg (HBRS) sind im Verlauf des Jahres 2013 Befragungen zu nachhaltigen, zertifizierten Lebensmitteln durchgeführt worden. Ziel war es, die Bedeutung von Fairtrade und Bio auf der Basis von Konsumenteneinschätzungen zu analysieren. Dazu wurden Wahrnehmung, Bekanntheitsgrad und Vertrauen, Kaufverhalten, Zahlungsbereitschaft sowie Glaubwürdigkeit gegenüber Fairtrade- und Bio-Produkten abgefragt. Der Kreis der Befragten umfasste die Gruppe der Studierenden, Mitarbeiter/innen und Professor(inn)en. Darüber hinaus konnten Differenzierungen nach Geschlecht, Einkommen und Alter vorgenommen werden. Die Ergebnisse zeigen unter anderem eine Skepsis – hier insbesondere bei der Gruppe der Studierenden – gegenüber der Glaubwürdigkeit bekannter Fairtrade- und Bio-Siegel. Dabei ist das Misstrauen gegenüber den Aussagen des Bio-Siegels deutlich stärker ausgeprägt. Bezüglich der Kaufbereitschaft und dem tatsächlichen Verhalten ist das Phänomen des attitude behaviour gap zu beobachten. Die Befragten halten Fairtrade zwar für unterstützenswert, drücken ihre Einstellung aber nicht in ihrem tatsächlichen Verhalten aus. Die Befragung zeigt, dass häufig Unklarheit über die inhaltlichen Aspekte der Faitrade- und Bio-Siegel besteht. Insbesondere mehr Aufklärung (Bewusstseinsbildung) und eine größere Transparenz des Fairtrade-Systems könnten hier entgegenwirken und dazu beitragen, dass Einstellungen sich auch in tatsächlichem Handeln widerspiegeln

Der verantwortungsvolle Konsument – Einstellungen von Wirtschafts- und Sozialwissenschaftlern

An den wirtschaftswissenschaftlichen Fakultäten der Technischen Hochschule Köln (TH Köln) und der Hochschule Bonn-Rhein-Sieg (HBRS) sind im Verlauf des Jahres 2013 Befragungen zu nachhaltigen, zertifizierten Lebensmitteln durchgeführt worden. Ziel war es, die Bedeutung von Fairtrade und Bio auf der Basis von Konsumenteneinschätzungen zu analysieren. Dazu wurden Wahrnehmung, Bekanntheitsgrad und Vertrauen, Kaufverhalten, Zahlungsbereitschaft sowie Glaubwürdigkeit in Bezug auf Fairtrade- und Bio-Produkte abgefragt. Der Kreis der Befragten umfasste die Gruppe der Studierenden, Mitarbeiter/innen und Professor(inn)en. Darüber hinaus konnten Differenzierungen nach Geschlecht, Einkommen und Alter vorgenommen werden. Die Ergebnisse sind in der Reihe „Forum NIL“ veröffentlicht worden. In der vorliegenden Studie sollte untersucht werden, ob Sozialwissenschaftler ein verantwortungsvolleres Konsumentenverhalten aufweisen als Wirtschaftswissenschaftler. Aus diesem Grunde, wurde die gleiche Befragung an der Fakultät für Sozialwissenschaften der TH Köln durchgeführt. Ein Vergleich der Befragungsergebnisse zeigte einerseits, dass Studierende, Mitarbeiter/innen und Professor(inn)en in den Sozialwissenschaften ein teilweise höheres Verantwortungsbewusstsein aufweisen. Dies gilt insbesondere in Bezug auf das bewusste Achten auf nachhaltige Produkte, die Zahlungsbereitschaft und den tatsächlichen Kauf von Fairtrade- und Bio-Produkten. Allerdings war auch bei den Befragten der Fakultät für Wirtschaftswissenschaften ein durchaus verantwortungsvolles Konsumentenverhalten erkennbar. Darüber hinaus konnte der generelle Vorwurf, dass sich eine Ökonomieausbildung negativ auf die Einstellung zu einem verantwortungsvollen Handeln auswirkt, anhand der Studienergebnisse nicht bestätigt werden. Vielmehr zeigte sich, dass nahezu keine Unterschiede zwischen den Antworten der Studienanfänger und Studierender höherer Semester an der Fakultät für Wirtschaftswissenschaften feststellbar waren

Parasites of non-native freshwater fishes introduced into england and wales suggest enemy release and parasite acquisition

When non-native species are introduced into a new range, their parasites can also be introduced, with these potentially spilling-over into native hosts. However, in general, evidence suggests that a high proportion of their native parasites are lost during introduction and infections by some new parasites from the native range might occur, potentially resulting in parasite spill-back to native species. These processes were investigated here using parasite surveys and literature review on seven non-native freshwater fishes introduced into England and Wales. Comparison of the mean numbers of parasite species and genera per population for each fish species England andWaleswith their native ranges revealed\9 % of the native parasite fauna were present in their populations in England and Wales. There was no evidence suggesting these introduced parasites had spilled over into sympatric native fishes. The non-native fishes did acquire parasites following their introduction, providing potential for parasite spill-back to sympatric fishes, and resulted in non-significant differences in overall mean numbers of parasites per populations between the two ranges. Through this acquisition, the non-native fishes also had mean numbers of parasite species and genera per population that were not significantly different to sympatric native fishes. Thus, the non-native fishes in England and Wales showed evidence of enemy release, acquired new parasites following introduction providing potential for spill-back, but showed no evidence of parasite spill-over

Tropheryma whipplei, the Whipple's disease bacillus, induces macrophage apoptosis through the extrinsic pathway

Tropheryma whipplei, the etiological agent of Whipple's disease, is an intracellular bacterium that infects macrophages. We previously showed that infection of macrophages results in M2 polarization associated with induction of apoptosis and interleukin (IL)-16 secretion. In patients with Whipple's disease, circulating levels of apoptotic markers and IL-16 are increased and correlate with the activity of the disease. To gain insight into the understanding of the pathophysiology of this rare disease, we examined the molecular pathways involved in T. whipplei-induced apoptosis of human macrophages. Our data showed that apoptosis induction depended on bacterial viability and inhibition of bacterial protein synthesis reduced the apoptotic program elicited by T. whipplei. Induction of apoptosis was also associated with a massive degradation of both pro- and anti-apoptotic mediators. Caspase-specific inhibition experiments revealed that initiator caspases 8 and 10 were required for apoptosis, in contrast to caspases 2 and 9, in spite of cytochrome-c release from mitochondria. Finally, the effector caspases 3 and 6 were mandatory for apoptosis induction. Collectively, these data suggest that T. whipplei induces apoptosis through the extrinsic pathway and that, beside M2 polarization of macrophages, apoptosis induction contributes to bacterial replication and represents a virulence trait of this intracellular pathogen

The challenge to verify ceramide's role of apoptosis induction in human cardiomyocytes - a pilot study

<p>Abstract</p> <p>Background</p> <p>Cardioplegia and reperfusion of the myocardium may be associated with cardiomyocyte apoptosis and subsequent myocardial injury. In order to establish a pharmacological strategy for the prevention of these events, this study aimed to verify the reliability of our human cardiac model and to evaluate the pro-apoptotic properties of the sphingolipid second messenger ceramide and the anti-apoptotic properties of the acid sphingomyelinase inhibitor amitryptiline during simulated cardioplegia and reperfusion ex vivo.</p> <p>Methods</p> <p>Cardiac biopsies were retrieved from the right auricle of patients undergoing elective CABG before induction of cardiopulmonary bypass. Biopsies were exposed to <it>ex vivo </it>conditions of varying periods of cp/rep (30/10, 60/20, 120/40 min). Groups: I (untreated control, n = 10), II (treated control cp/rep, n = 10), III (cp/rep + ceramide, n = 10), IV (cp/rep + amitryptiline, n = 10) and V (cp/rep + ceramide + amitryptiline, n = 10). For detection of apoptosis anti-activated-caspase-3 and PARP-1 cleavage immunostaining were employed.</p> <p>Results</p> <p>In group I the percentage of apoptotic cardiomyocytes was significantly (p < 0.05) low if compared to group II revealing a time-dependent increase. In group III ceramid increased and in group IV amitryptiline inhibited apoptosis significantly (p < 0.05). In contrast in group V, under the influence of ceramide and amitryptiline the induction of apoptosis was partially suppressed.</p> <p>Conclusion</p> <p>Ceramid induces and amitryptiline suppresses apoptosis significantly in our ex vivo setting. This finding warrants further studies aiming to evaluate potential beneficial effects of selective inhibition of apoptosis inducing mediators on the suppression of ischemia/reperfusion injury in clinical settings.</p

Activation of Akt by the Bacterial Inositol Phosphatase, SopB, is Wortmannin Insensitive

Salmonella enterica uses effector proteins translocated by a Type III Secretion System to invade epithelial cells. One of the invasion-associated effectors, SopB, is an inositol phosphatase that mediates sustained activation of the pro-survival kinase Akt in infected cells. Canonical activation of Akt involves membrane translocation and phosphorylation and is dependent on phosphatidyl inositide 3 kinase (PI3K). Here we have investigated these two distinct processes in Salmonella infected HeLa cells. Firstly, we found that SopB-dependent membrane translocation and phosphorylation of Akt are insensitive to the PI3K inhibitor wortmannin. Similarly, depletion of the PI3K regulatory subunits p85α and p85ß by RNAi had no inhibitory effect on SopB-dependent Akt phosphorylation. Nevertheless, SopB-dependent phosphorylation does depend on the Akt kinases, PDK1 and rictor-mTOR. Membrane translocation assays revealed a dependence on SopB for Akt recruitment to Salmonella ruffles and suggest that this is mediated by phosphoinositide (3,4) P2 rather than phosphoinositide (3,4,5) P3. Altogether these data demonstrate that Salmonella activates Akt via a wortmannin insensitive mechanism that is likely a class I PI3K-independent process that incorporates some essential elements of the canonical pathway