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Female Antarctic fur seals returning ashore after foraging trips were restrained, and fecal material was obtained by introducing approximately one litre of warm water into the animal's colon via the anus. The material then naturally expelled by the animal was collected and analyzed. Of 159 enemas attempted, 148 (93%) produced enough fecal material for subsequent analysis, i.e. , where ten or more carapaces or one or more otoliths were recovered. The method produced no obvious external signs of damage to any of the animals, and all were observed suckling their pups within the same season. There was no significant difference in the mean krill sizes collected by enema compared to scat sampling. Also, using their incidence, there was no significant difference in the two sampling methods for any of the fish species considered, though using the proportion of otoliths of a given species of the total otoliths found, there was a difference with one species, Gymnoscopelus nicbolsi. With this technique, it is possible to target individual seals or specific demographic categories for diet analysis. This means that, by using feces collected from enemas, a wider range of questions can be addressed than are currently possible using scat collection alone.  相似文献   
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PurposeTo evaluate patient-level colorectal cancer outcomes in relation to residential income and racial segregation and composition of the neighborhood surrounding the diagnosing hospitals, and characterize presence of cancer-relevant diagnosis and treatment modalities that might contribute to these associations.MethodsWe utilized Georgia state cancer registry data (2010–2015), matching diagnosis information to hospital technology provided by the American Hospital Association and spatial information to the US Census. We modeled time-to-treatment and survival time, using Cox proportional hazards models, stratified by segregation. Segregation was examined as residential economic and racial evenness (Atkinson index) and isolation (isolation index) and mean income at the Census tract level. To assess possible contributing factors, analysis of hospital diagnosis and treatment technologies in relation to segregation was conducted.ResultsAverage income of the Census tract and racial residential segregation of the diagnosing hospital’s neighborhood was generally unassociated with time-to-treatment or survival time. Higher income evenness around the diagnosing hospital was associated with shorter time-to-treatment, with no association with time-to-death. Higher income isolation for the diagnosing hospital, conversely, was associated with longer times to treatment, but also longer survival times. Hospitals in regions with higher level of residential income segregation were less likely to have a particular diagnosing or treatment technologies, such as virtual colonoscopy and chemotherapy.ConclusionHospital resources may be a function of their immediate economic environment, and this may have influence on cancer outcomes. Future work should evaluate patient outcomes in light of technologies or therapies utilized within particular economic environments.  相似文献   
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Neck collars of man-made marine debris were seen on 208 Antarctic fur seals (and removed from 170) during the 142 days of the 1988–1989 pup-rearing season at Bird Island, South Georgia. This represents at least 0.1% of the total Bird Island population and a minimum of 0.4% of animals in the best covered areas; a maximum value might approach 1%. Polypropylene straps (packaging bands) formed 59% of collars, nylon string (16%), fishing net (13%) and six other materials comprised the rest. Males accounted for 71% of entanglements, 88% of which were of young (1–4 yr old) animals; females accounted for 64% of animals older than this. Obvious physical injury was being caused to 30% of animals and only on 19% of animals was the collar loose enough potentially to come off. The magnitude of the problem at South Georgia is similar to that with northern fur seals at the Pribilof Islands, where a significant population decline has occurred concurrently. Antarctic fur seals are still increasing in numbers but stricter controls on the jettisoning of debris into the Southern Ocean ate needed if the entanglement problem is not to increase beyond the level of a potential threat.  相似文献   
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Siliceous “star cobbles”, referred to the enigmatic genus Brooksella, are abundant in the Conasauga Formation of the Coosa River Valley of Alabama and Georgia, USA. Explaining the phylogenetic affinities and taphonomic history of Brooksella has been difficult and contentious. Brooksella has, at times, been referred to: 1, the cnidarian order Scyphomedusae; 2, the cnidarian class Protomedusae (order Brooksellida); 3, as algae; 4, as a trace fossil; and 5, as a feature of inorganic origin.Macroscopic, microscopic, and computer-assisted tomographic analysis of Brooksella from the Conasauga Formation suggests that the “star cobbles” represent exceptionally preserved body fossils of simple construction. Morphology of star cobbles is most consistent with a siliceous (hexactinellid) sponge interpretation. Specimens show wide morphologic variation, including gradational patterns, suggesting that a single species name (Brooksella alternata) should be used to embrace all forms described from the Coosa Valley. B. alternata includes specimens having a variable number of radially disposed lobes divided by radial grooves, and often a central opening inferred to be an osculum on one side. Lobes in many specimens terminate in small openings. Small craterlike structures, inferred to be ostia, are present on the external surface. Radial internal cavities occupy the lobes. Specimens from the Conasauga Formation have siliceous spicules preserved surficially and internally.The three-dimensional nature of most “star cobbles” suggests rapid fossil diagenesis, perhaps mediated by the activities of microbial consortia that quickly formed biofilms around the dead hosts.  相似文献   
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More white-chinned petrels (Procellaria aequinoctialis) are accidentally killed in fisheries than probably any other seabird in the world, but the population impact of this mortality is poorly understood, partly because there have been no recent estimates of the species’ abundance. The breeding aggregation on the sub-Antarctic island of South Georgia is believed to be larger than all others combined. We estimated the size of this population by calculating the area of suitable habitat and the density of occupied burrows within it. Some 670,000 occupied nests were estimated for the island at mid-incubation, representing 0.9 million pairs of breeding-age birds associated with South Georgia in the survey seasons (2005/06 and 06/07). This is 40–45% of the previous estimate, but still represents well over half of the global population. If the population is declining due to fishery bycatch, as is likely, the scale of annual mortality in this population alone is at least in the high tens of thousands, and plausibly hundreds of thousands.  相似文献   
118.
Improved method for ribonuclease zymogram   总被引:1,自引:0,他引:1  
An improved method for ribonuclease zymogram in agarose overlays is described which enables significantly enhanced sensitivity and the avoidance of false-positive activity. Two critical aspects of the zymogram method—the fixation/staining technique and the RNA substrate concentration—were evaluated for the RNase activity in RNase A and in human serum and urine. The zymogram method is sensitive to at least 10 pg of RNase A and does not show a false-positive reaction from 1500 μg of non-RNase protein following electrophoresis in thin-layer polyacrylamide gel.  相似文献   
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Measurement of carbon and nitrogen stable isotope ratios (delta 13C and delta 15N) in samples of human bone collagen (n = 93) from a temporal series of four prehistoric (early preagricultural, late preagricultural, early agricultural, late agricultural) and two historic (early contact, late contact) periods from the Georgia Bight, a continental embayment on the southeastern U.S. Atlantic coast, reveals a general temporal trend for less negative delta 13C values and less positive delta 15N values. This trend reflects a concomitant decrease in emphasis on marine resources and increased reliance on C4-based resources, especially maize. This dietary reorientation is most apparent for the early agricultural sample (AD 1150-1300), coinciding with the Mississippian fluorescence in the eastern United States. There is, however, a shift toward the use of C3 (non-maize) foods during the last prehistoric period (AD 1300-1450), which is likely related to environmental stress and social disruption. A heavier use of maize and terrestrial resources in general after the establishment of mission centers on barrier islands is indicated. A reduced dietary breadth during the mission period may have contributed to the extinction of these populations in the eighteenth century.  相似文献   
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