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The conservation benefits of maintaining social groupings during and after animal translocations are unclear. Although some studies report improved post-release survival, others found no discernible influence on reintroduction success. Understanding the effects of social groupings is difficult because release methods can influence the animals’ ability to maintain social groups. We explored this relationship by first studying whether release protocols influenced post-release cohesion in the communal burrowing bettong Bettongia lesueur, and then investigating whether maintenance of social cohesion conferred any post-release advantage. We released bettongs into a small (8 ha) and large (2,600 ha) area and compared the proportion that maintained social groupings in the different settings. The proportion of bettongs sharing with previous warren co-occupants was higher than expected by chance in both areas, however, a significantly higher proportion of bettongs maintained social groupings in the small (75%) compared to the large release area (13%). This suggests bettongs prefer to maintain social groupings but are unable to locate members of their group in large release areas. Bettongs that did maintain social groupings showed no difference in reproductive or health outcomes compared to those that formed new social groupings, suggesting no benefit to reintroduction success. We conclude that release protocols can influence post-release cohesion, but that greater cohesion does not necessarily confer advantages to group-living animals. To test the importance of social cohesion, further research on reintroductions should compare post-release parameters for animals released using protocols that do and do not facilitate maintenance of social groupings.
About 500 remote, mainly compact clusters of galaxies have been identified on ESO (R) Schmidt plates; around 40 of these have been observed with the ESO CCD camera on the Danish 1.5-m telescope on La Silla. We describe the method of identifying the clusters and give some preliminary photometric results.
Lateral fluctuations of shoreline positions along shallow basinal margins often result in spatially and temporally overprinted (palimpsested) firmground or hardground surfaces (Frey and Basan, 1981). Recent palimpsested surfaces can teach us a great deal about the fossil record, particularly when we view them taphonomically. For the last few years we have been studying such surfaces along the seaward coast of St. Catherines Island, Georgia. In this paper we will first briefly discuss the modern salt marsh at St. Catherines Island, and its invertebrate inhabitants. This will form a basis for recognition and description of relict marsh surfaces. We will next describe the relict salt marsh surface that is currently being exhumed by coastal erosion and palimpsested by other invertebrate communities. Such palimpsested events also represent heterochronous community replacement–the disjunct temporal and (usually) spatial overprinting of an older community (or biogenic surface) by one (or more) younger communities. This interprets “replacement” as a passive, generally species non-interactive, phenomenon (contra Miller, 1986). Lastly, we will make some rather broad comparisons between the St. Catherines Island setting and what we interpret as analogous situations recorded in the Carboniferous strata of the Appalachian Basin.
Stratigraphy provides a basic temporal and spatial framework for all studies of earth history. The foundations of stratigraphy were built in the 17th and 18th centuries through the efforts of Steno and Smith. Formalization of the principles of organic evolution followed closely in the mid-19th century with the publication of the Origin of Species. Although paleoecological observations span centuries, the establishment of paleoecology as a scientific discipline is a 20th century phenomenon. Initially, paleontology (paleobiology) was an integral part of stratigraphy and housed the subdisciplinary studies of evolution and paleoecology. Retention of a stratigraphic framework soon became difficult, perhaps due to the potential for circular reasoning in the evolutionary study of fossils. If the rock record was subdivided on the basis of fossils, how could the evolutionary relationships of these organisms be evaluated when they, or related forms, had been used to construct the temporal framework?
Whole apples have not been previously implicated in outbreaks of foodborne bacterial illness. We investigated a nationwide listeriosis outbreak associated with caramel apples. We defined an outbreak-associated case as an infection with one or both of two outbreak strains of Listeria monocytogenes highly related by whole-genome multilocus sequence typing (wgMLST) from 1 October 2014 to 1 February 2015. Single-interviewer open-ended interviews identified the source. Outbreak-associated cases were compared with non-outbreak-associated cases and traceback and environmental investigations were performed. We identified 35 outbreak-associated cases in 12 states; 34 (97%) were hospitalized and seven (20%) died. Outbreak-associated ill persons were more likely to have eaten commercially produced, prepackaged caramel apples (odds ratio 326·7, 95% confidence interval 32·2–3314). Environmental samples from the grower's packing facility and distribution-chain whole apples yielded isolates highly related to outbreak isolates by wgMLST. This outbreak highlights the importance of minimizing produce contamination with L. monocytogenes. Investigators should perform single-interviewer open-ended interviews when a food is not readily identified.
The University of Cambridge Radiocarbon Dating Laboratory has been completely rebuilt and modernized, incorporating new techniques developed here for the various stages of measurements. Sample radioactivity is measured in gas proportional counters after conversion to highly purified CO2. Four counters are mounted within a single anticoincidence shield consisting of plastic scintillation material. This is surrounded by a graded cosmic ray shield of low radioactive steel, boron loaded wax, and finally, about 16 tons of ancient low radioactive lead blocks. The electronics are all solid state devices except for the stabilized high voltage supplies.
The past triennium was characterized by important advances in several directions within the broad field of this Commission. Among the most exciting events were the Phobos 2 and Voyager 2 missions to Mars/Phobos and Neptune/Triton; their navigation was critically dependent on precise space- and ground-based observations as well as refined theoretical models of the motions in the solar system. Among many other achievements, the secular acceleration of Phobos was accurately measured and the dynamical analysis of the ring-like arcs at Neptune has just begun.
The present report covers the period from 1 January 1979 to 31 December 1981. This period includes the first eight months (to 26 August) of the year 1979, which was part of the period in office of the previous Executive Committee; it does not include the first eight months of 1982, still the period of responsibility of the present Executive Committee (to 27 August 1982).
The address of the General Secretary at the XVIIIth General Assembly will include a report for the period 1 January – 16 August 1982.
This report includes a summarized financial report for the calendar years 1979, 1980 and 1981 and a budget proposal for the calendar year 1982, closing the 3-year budgetary period 1979-1982.
Throughout the triennium, Commission 6 has interacted with the Central Bureau for Astronomical Telegrams (CBAT), most ably headed by Brian Marsden. As will be seen from his report below, the use by scientists of the Circulars for rapid dissemination of astronomical and related news continues unabated.
The present report of Commission 15 has been, as usual, prepared primarily by the chairpersons of the two working groups. E. Tedesco wrote the section about Asteroids and Meteorites, with the assistance of A. Cellino, G. Consolmagno and C.-I. Lagerkvist. W. F. Huebner prepared the section about Comets, with the assistance of J. Benkhoff, H. Boehnhardt, J. Brandt, M. T. Capria, A. Cochran, G. Cremonese, M. Duncan, W. Huntress, H. Levison, and G. P. Tozzi. Moreover, the whole document has been assembled by K. Muinonen, who did the final editing, to merge the two reports and fit the document into the allotted space. Material taken from both major areas regarding the relationship between comets and asteroids has been combined into a single section.
The field of nanophotonics has experienced a dramatic development in recent years, which requires ample candidate structures to achieve desirable functionalities. For many novel device designs in emerging field of transformation optics, optical metamaterials, and others, non-uniform and non-conformal thin films as well as three-dimensional (3D) structures are necessary to achieve advanced functionalities. Here, we report several techniques utilizing angled physical vapor deposition to obtain unique and complex 3D structures such as films with tapered thickness on planar substrates, tapered or uniform films on curved surfaces, and 3D nanorod arrays. These structures could enrich the existing practical design space for applications in nanophotonics and nanoelectronics.
Methodological problems and hardware/software requirements of efficient automatic classification of objective prism stellar spectra are described on the basis of experience from ‘microphotometer-computer’ classification. Significant advances in hardware (two-dimensional scanners, on-line computers) as well as in software (image processing techniques) have now brought high-speed, exhaustive, automatic classification within reach. Some astronomical implications of automatic spectral surveys are discussed.