Orientation, Migration Routes and Flight Behaviour of Knots, Turnstones and Brant Geese Departing from Iceland in Spring

Flight behaviour and orientation of 303 flocks (31,200 individuals) of migrating Knots and Turnstones and 77 flocks (3200 individuals) of Brant Geese departing from Iceland towards Nearctic breeding grounds were recorded during three spring seasons 1986-88. Flocks were tracked by telescope and optical range finder at three observation sites in western Iceland during the peak period of migratory departure, 25 May-1 June. Departing waders climbed steeply, often by circling and soaring flight, with an average climbing rate of 1.0 m/s, up to altitudes 600-2000 m asl. With unfavourable winds, the waders descended to fly low over the sea surface. Brant Geese usually travelled at lower altitudes, the majority below 100 m above the sea, and were more prone towards following coastlines than waders. The birds departed in flight formations, with mean flock sizes 100-200 individuals in the Knot, 13-70 individuals in the Turnstone and about 40 individuals in the Brant Goose flocks. Waders generally departed in the afternoon or evening, during rising or high tide. Significant differences in daily timing between seasons were associated with between-year differences in the tidal cycle. Within the season, departures took place earlier in relation to high tide as the season progressed. Brant Goose departures occurred in the morning and late evening. Mean orientation was close to 300 degrees in all three species, with angular deviation 21-26 degrees. It is concluded that the overwhelming majority of the birds are bound for breeding sites in northern Canada and northwest Greenland. The main flight route, as can be deduced on the basis of visual, radar and ringing data from Iceland, Greenland and Canada, falls in the 290-310 degrees rhumbline sector from Iceland, across the Greenland ice cap. There are simple celestial and magnetic orientation rules that would allow birds to orient from Iceland to northern Canada close to a great circle route, but not along the rhumbline route used by the Knots, Turnstones and Brant Geese.

Strongly Enhanced Backward Emission of Electrons in Transfer and Ionization

We studied three-dimensional angular distributions and longitudinal momentum spectra of electrons ejected in transfer plus ionization (TI), i.e., the ejection of one and the capture of a second target electron, for ion-helium collisions. We observe a pronounced structure strongly focused opposite to the projectile beam direction, which we associate with a new correlated TI mechanism proposed recently. This process contributes significantly to the total cross sections over a broad range of perturbations η, even at η as large as 0.5, where uncorrelated TI mechanisms were thought to be dominant

Mutual Projectile and Target Ionization in 1-MeV/amu N⁴⁺ and N₅⁺+ He Collisions

We have studied mutual projectile and target ionization in 1-MeV/amu N4+ and N5++He collisions in kinematically complete experiments by measuring the momenta of the recoil ion and both ejected electrons in coincidence with the charge-changed projectiles. By means of four-particle Dalitz plots, in which multiple differential cross sections are presented as a function of the momenta of all four particles, experimental spectra are compared with theoretical results from various models. The experimental data are qualitatively reproduced by higher-order calculations, where good agreement is achieved for N5++He collisions, while some discrepancies persist for N4++He collisions

Association of respiratory symptoms and lung function with occupation in the multinational Burden of Obstructive Lung Disease (BOLD) study

Background Chronic obstructive pulmonary disease has been associated with exposures in the workplace. We aimed to assess the association of respiratory symptoms and lung function with occupation in the Burden of Obstructive Lung Disease study. Methods We analysed cross-sectional data from 28 823 adults (≥40 years) in 34 countries. We considered 11 occupations and grouped them by likelihood of exposure to organic dusts, inorganic dusts and fumes. The association of chronic cough, chronic phlegm, wheeze, dyspnoea, forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1)/FVC with occupation was assessed, per study site, using multivariable regression. These estimates were then meta-analysed. Sensitivity analyses explored differences between sexes and gross national income. Results Overall, working in settings with potentially high exposure to dusts or fumes was associated with respiratory symptoms but not lung function differences. The most common occupation was farming. Compared to people not working in any of the 11 considered occupations, those who were farmers for ≥20 years were more likely to have chronic cough (OR 1.52, 95% CI 1.19–1.94), wheeze (OR 1.37, 95% CI 1.16–1.63) and dyspnoea (OR 1.83, 95% CI 1.53–2.20), but not lower FVC (β=0.02 L, 95% CI −0.02–0.06 L) or lower FEV1/FVC (β=0.04%, 95% CI −0.49–0.58%). Some findings differed by sex and gross national income. Conclusion At a population level, the occupational exposures considered in this study do not appear to be major determinants of differences in lung function, although they are associated with more respiratory symptoms. Because not all work settings were included in this study, respiratory surveillance should still be encouraged among high-risk dusty and fume job workers, especially in low- and middle-income countries.publishedVersio

Airline Panel Discussion: What Are the Important Research Issues for the Airline Industry and How Can Industry Help Researchers Undertake Projects in These Areas?

One of several panel discussions about airlines held several times over the course of the conference