The impact of different concentrations of a pyrethroid insecticide on the cyclic gas exchange cycles on bumble bees

contribution to session II Bumblebees and other bee specie

Ultrafast electronic processes in an insulator The Be and O sites in BeO

The short time dynamics of amorphous beryllium oxide a BeO has been investigated for electronic excitation ionization by fast incident electrons, as well as by Ar7 , Ar15 , Xe15 , and Xe31 ions at velocities of 6 10 the speed of light. Site specific Auger electron spectra induced by fast heavy ions are the central point of this investigation. Electron induced Auger spectra serve as a reference and electron energy loss EELS spectroscopy as well as resonant inelastic X ray scattering RIXS are invoked for quantitative understanding. For the heavy ion case, we observe strong variations in the corresponding spectral distributions of Be K and O K Auger lines. These are related to local changes of the electron density, of the electron temperature and even of the electronic band structure of BeO on a femtosecond time scale after the passage of highly charged heavy ions

Discontinuous gas exchange cycles and active ventilation in pupae of the bumblebee Bombus terrestris

Discontinuous release of CO2 (bursts) or discontinuous gas exchange cycles (DGC), metabolic rate (MR) and ventilation movements were simultaneously recorded from the pupae of the bumblebee Bombus terrestris by means of an electrolytic respirometer and an infrared gas analyser (IRGA) combined with an infrared actograph (IRA). After recovering from stress, the early stage pupae showed irregular continuous respiration, mid-stage pupae displayed regular DGC. The bursts of CO2 release tended to coincide with abdominal contractions. In late stage pupae all bursts of CO2 were associated with active ventilation. During interburst periods, spikes appeared on the respirograms interpreted as micro-cycles of passive suction ventilation (PSV). After removal from their cocoons, the pupae exhibited frequent periods of muscular activity due to stress. Water loss of pupae inside cocoons was significantly less than that from pupae without cocoons

Effect of dietary linseed supplements on ù-3 PUFA content and on IGF-1 expression in broiler tissues

The aim of this study was to evaluate the effect of ù-3 PUFA-rich linseed-supplemented diet on the ù-6/ù-3 PUFA content and IGF-I mRNA expression in broiler tissues. Broilers (50 of 21 d old and 90 of 42 d old) were divided into groups according to dietary additives: 1.5% linseed oil (LO), 3.0% LO, 15% linseed cake (LC) and 30% LC and to the duration of modified feeding (121, 142 and 2242 days). PUFA content in breast muscles was assayed by gas chromatography and IGF-I mRNA content in liver, muscle and leukocytes was measured by one step RT-PCR. The experimental diets improved the ù-6/ù-3 PUFA ratio through a threefold increase in the ù-3 PUFA content in the breast muscle. The changes in PUFA content were accompanied by changes in IGF-1 gene expression levels in tissues. Therefore, both paracrine and autocrine manner of IGF-1 action are likely to be involved. 15% LC at starting period or 1.5% LO in final diet can be advised as optimal for enriching broiler meat with ù-3 fatty acids.