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Sample records for ringed mute swans

  1. Mute swans: Natural (?) environmental indicators

    Science.gov (United States)

    Day, D.; Perry, Matthew C.

    2004-01-01

    The rapid expansion of the Chesapeake Bay's population of feral mute swans (Cygnus olar), coupled with a dramatic Bay-wide decline in submerged aquatic vegetation (SAV), has fueled much of the current debate surrounding the need for a management plan to protect the aquatic food resources that are critical to many species native to the Bay. Crucial to this decision process is a sound understanding of the ecological ramifications of having the year-round presence of a large, nonnative, aquatic herbivore on the Bay. Ultimately, this will require a quantitative assessment of the ecological harm currently posed by mute swans before a biologically defensible management strategy can be developed. Unfortunately, very little new information specific to the Bay's mute swan population has been gathered since Reese first studied them in the late 1960s and 1970s. While the debate over what to do about the rapidly expanding mute swan population continues, there is much that can be gained from study of this beautiful intruder. Several recent studies of the feeding habits of mute swans have shown that mutes can provide a unique barometer, or indicator, of environmental conditions. Because of their reliance on SAV as a primary food source, monitoring the density of swans utilizing a particular area can give some indication of the status of the area's grass beds. This phenomenon was clearly demonstrated during the summer of 1999 when there was a dramatic decline in the number of swans observed around the Eastern Neck NWR, a traditional population stronghold. The shift in bird use was precipitated by a rapid, large-scale collapse of the area's aquatic grass beds, possibly the result of a prolonged drought. During the winter of 2000/2001, a similar ecological assessment was conducted by comparing body weights of swans collected from Tangier Sound, an area with relatively abundant grass beds, and swans from the waters adjacent to Eastern Neck Island. Swans weights tended to reflect the

  2. Food habits of mute swans in the Chesapeake Bay

    Science.gov (United States)

    Perry, M.C.; Osenton, P.C.; Lohnes, E.J.R.; Perry, Matthew C.

    2004-01-01

    Unlike the tundra swan (Cygnus columbianus) that migrate to the Bay for the winter, the mute swan (Cygnus olor) is a year long resident and therefore has raised concerns among research managers over reports of conflicts with nesting native water birds and the consumption of submerged aquatic vegetation (SAV). Although data on the reduction of SAV by nesting mute swans and their offspring during the spring and summer are limited, food-habits data show that mute swans rely heavily on SAV during these months. Analyses of the gullet and gizzard of mute swans indicate that widgeon grass (Ruppia maritima) and eelgrass (Zostera marina) were the most important food items to mute swans during the winter and spring. Other organisms were eaten by mute swans, but represent small percentages of food. Corn (Zea mays) fed to the swans by Bay residents in late winter probably supplements their limited vegetative food resources at that time of year.

  3. The exotic mute swan (Cygnus olor) in Chesapeake Bay, USA

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    Perry, M.C.; Perry, M.C.

    2002-01-01

    The exotic mute swan (Cygnus olor) has increased its population size in Chesapeake Bay (Maryland and Virginia) to approximately 4,500 since 1962 when five swans were released in the Bay. The Bay population of mute swans now represents 30% of the total Atlantic Flyway population (12,600) and has had a phenomenal increase of 1,200% from 1986 to 1999. Unlike the tundra swans (Cygnus columbianus) that migrate to the Bay for the winter, the mute swan is a year-long resident, and, therefore, reports of conflicts with nesting native waterbirds and the consumption of submerged aquatic vegetation (SAV) have raised concerns among resource managers. Populations of black skimmers (Rynchops niger) and least terns (Sterna antillarum) nesting on beaches and oyster shell bars have been eliminated by molting mute swans. Although data on the reduction of SAV by nesting mute swans and their offspring during the spring and summer are limited, food habits data show that mute swans rely heavily on SAV during these months. Widgeon grass (Ruppia maritima) constituted 56% and eel grass (Zostera marina) constituted 43% of the gullet food of mute swans. Other SAV and invertebrates (including bryozoans, shrimp, and amphipods) formed a much smaller amount of the food percentage (1%). Invertebrates are believed to have been selected accidently within the vegetation eaten by the swans. Corn (Zea mays) fed to swans by Bay residents during the winter probably supplement limited vegetative food resources in late winter. A program to control swan numbers by the addling of eggs and the killing of adult swans has been a contentious issue with some residents of the Bay area. A management plan is being prepared by a diverse group of citizens appointed by the Governor to advise the Maryland Department of Natural Resources on viable and optimum options to manage mute swans in the Maryland portion of Chesapeake Bay. Hopefully, the implementation of the plan will alleviate the existing conflicts to the

  4. Size and mass of grit in gizzards of sandhill cranes, tundra swans, and mute swans

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    Franson, J. Christian; Hansen, Scott P.; Duerr, Adam E.; DeStefano, Stephen

    2001-01-01

    Because it has been suggested that waterbirds may ingest lost or discarded lead fishing weights as grit, we examined grit in the gizzards of Sandhill Cranes (Grus canadensis), Tundra Swans (Cygnus columbianus), and Mute Swans (Cygnus olor), three species where individuals have been poisoned by the ingestion of lead fishing weights. The greatest proportion (by mass) of grit in gizzards of Sandhill Cranes consisted of particles with a minimum dimension of 2.36-4.75 mm. Grit particles in swans were much smaller, with the most prevalent (by mass) being 0.6-1.18 mm. The greatest dimension of the largest grit particle found in cranes and swans was 17.4 mm and 14.0 mm, respectively. The U.S. Environmental Protection Agency has proposed a ban on lead fishing weights of ≤25.4 mm in any dimension. Based on the size of grit particles that we found in gizzards of Sandhill Cranes, Mute Swans, and Tundra Swans, we believe it is unlikely that individuals of those species would ingest, as grit, lead fishing weights larger than 25.4 mm in any dimension.

  5. Mute swans and their Chesapeake Bay habitats: proceedings of a symposium

    Science.gov (United States)

    Perry, M.C.

    2004-01-01

    The symposium 'Mute Swans and their Chesapeake Bay Habitats,' held on June 7, 2001, provided a forum for biologists and managers to share research findings and management ideas concerning the exotic and invasive mute swan (Cygnus olar). This species has been increasing in population size and is considered by many to be a problem in regard to natural food resources in the Bay that are used by native waterfowl during the winter months. Other persons, however, feel that resource managers are attempting to create a problem to justify more killing of waterfowl by hunters. Some persons also believe that managers should focus on the larger issues causing the decline of native food resources, such as the unabated human population increase in the Bay watershed and in the immediate coastal areas of the Bay. The symposium, sponsored by the Wildfowl Trust of North America and the U.S. Geological Survey, provided the atmosphere for presentation of mute swan data and opinions in a collegial setting where discussion was welcomed and was often informative and enthusiastic. An interesting historic review of the swan in regard to the history of mankind was presented, followed by a discussion on the positive and negative effects of invasive species. Biologists from different parts of the continent discussed the population status of the species in several states in the east and in the Great Lakes area. Data on the food habits of this species were presented in regard to submerged aquatic vegetation, and an interesting discussion on the role that the food habits of Canada geese in regard to native vegetation was presented. Findings and recommendations of the Mute Swan Task Force were presented. Finally, a representative of the Friends of Animals gave a thought-provoking presentation in defense of the mute swan. The presentations, in general, provided the necessary information and recommendations to allow managers to proceed with management of this controversial species with new and

  6. Hematological parameters in relation to age, sex and biochemical values for mute swans (Cygnus olor).

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    Dolka, B; Włodarczyk, R; Zbikowski, A; Dolka, I; Szeleszczuk, P; Kluciński, W

    2014-06-01

    The knowledge of the correct morphological and biochemical parameters in mute swans is an important indicator of their health status, body condition, adaptation to habitat and useful diagnostic tools in veterinary practice and ecological research. The aim of the study was to obtain hematological parameters in relation to age, sex and serum biochemistry values in wild-living mute swans. We found the significant differences in the erythrocyte count, hematocrit, hemoglobin concentration and erythrocyte sedimentation rate in relation to age of mute swans. There were no differences in hematological values between males and females. The leukogram and H/L ratio did not vary by age and sex in swans. Among of biochemical parameters the slightly increased AST, ALP, CK, K, urea, decreased CHOL and TG values were recorded. As far as we know, this is the first study in which the morphometric parameters of blood cells in mute swans were presented. We found extremely low concentration of lead in blood (at subthreshold level). No blood parasites were found in blood smears. The analysis of body mass and biometric parameters revealed a significant differences dependent on age and sex. No differences in the scaled mass index were found. Our results represent a normal hematologic and blood chemistry values and age-sex related changes, as reference values for the mute swan.

  7. Impacts of mute swans (Cygnus olor) on submerged aquatic vegetation in Illinois River Valley backwaters

    Science.gov (United States)

    Stafford, Joshua D.; Michael W. Eichholz,; Adam C. Phillips,

    2012-01-01

    Wetland loss in North America has been considerable and well documented, and the establishment of exotic species in remaining wetlands can further reduce their ability to support native flora and fauna. In the Chesapeake Bay and Great Lakes ecosystems, exotic mute swans (Cygnus olor) have been found to negatively impact wetlands through degradation of submerged aquatic vegetation (SAV) communities. Mute swan populations have expanded into many areas of mid-continental North America outside the Great Lakes ecosystem, but the environmental impact of these populations is not well known. Mid-continental wetlands in North America differ in physical characteristics (e.g., size, depth, and permanency) and aquatic vegetation species composition compared to wetlands in other areas where mute swans have been studied and, thus, may be more or less susceptible to degradation from swan herbivory. To investigate the impact of mute swan herbivory on SAV communities in mid-continent wetlands, we used exclosures to prevent swans from foraging in 2 wetland complexes in central Illinois. Above-ground biomass of vegetation did not differ between exclosures and controls; however, mean below-ground biomass was greater in exclosures (52.0 g/m2, SE = 6.0) than in controls (34.4 g/m2 SE = 4.0). Thus, although swan densities were lower in our study region compared to that of previous studies, we observed potentially detrimental impacts of swan herbivory on below-ground biomass of SAV. Our results indicate that both above-ground and below-ground impacts of herbivory should be monitored, and below-ground biomass may be most sensitive to swan foraging.

  8. Elemental contaminants in livers of mute swans on lakes Erie and St. Clair.

    Science.gov (United States)

    Schummer, Michael L; Petrie, Scott A; Badzinski, Shannon S; Deming, Misty; Chen, Yu-Wei; Belzile, Nelson

    2011-11-01

    Contaminant inputs to the lower Great Lakes (LGL) have decreased since the 1960s and 1970s, but elemental contaminants continue to enter the LGL watershed at levels that are potentially deleterious to migratory waterfowl. Mute swans (Cygnus olor) using the LGL primarily eat plants, are essentially nonmigratory, forage exclusively in aquatic systems, and have increased substantially in number in the last few decades. Therefore, mute swans are an ideal sentinel species for monitoring elemental contaminants available to herbivorous and omnivorous waterfowl that use the LGL. We investigated hepatic concentrations, seasonal dynamics, and correlations of elements in mute swans (n = 50) collected at Long Point, Lake Erie, and Lake St. Clair from 2001 to 2004. Elements detected in liver at levels potentially harmful to waterfowl were copper (Cu) [range 60.3 to 6063.0 μg g(-1) dry weight (dw)] and selenium (SE; range 1.6 to 37.3 μg g(-1) dw). Decreases in aluminum, Se, and mercury (Hg) concentrations were detected from spring (nesting) through winter (nonbreeding). Elemental contaminants may be more available to waterfowl during spring than fall and winter, but study of seasonal availability of elements within LGL aquatic systems is necessary. From April to June, 68% of mute swans had Se levels >10 μg g(-1), whereas only 18% of swans contained these elevated levels of Se from July to March. An increase in the number of mute swans at the LGL despite elevated levels of Cu and Se suggests that these burdens do not substantially limit their reproduction or survival. Se was correlated with Cu (r = 0.85, p < 0.01) and Hg (r = 0.65, p < 0.01), which might indicate interaction between these elements. Some element interactions decrease the toxicity of both elements involved in the interaction. We recommend continued research of elemental contaminant concentrations, including detailed analyses of biological pathways and element forms (e.g., methylmercury) in LGL waterfowl to help

  9. Highly pathogenic avian influenza virus (H5N1) in experimentally infected adult mute swans.

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    Kalthoff, Donata; Breithaupt, Angele; Teifke, Jens P; Globig, Anja; Harder, Timm; Mettenleiter, Thomas C; Beer, Martin

    2008-08-01

    Adult, healthy mute swans were experimentally infected with highly pathogenic avian influenza virus A/Cygnus cygnus/Germany/R65/2006 subtype H5N1. Immunologically naive birds died, whereas animals with preexisting, naturally acquired avian influenza virus-specific antibodies became infected asymptomatically and shed virus. Adult mute swans are highly susceptible, excrete virus, and can be clinically protected by preexposure immunity.

  10. Fatal verminous pharyngitis and esophagitis caused by Streptocara incognita in mute swans (Cygnus olor).

    Science.gov (United States)

    Alić, A; Prasović, S; Hodzić, A; Besirović, H; Residbegović, Emina; Omeragić, J

    2013-03-01

    Streptocara spp. infections are reported to cause gastritis, proventriculitis, esophagitis, and pharyngitis in various waterfowls, especially diving ducks. In the present paper, we describe severe fatal diphtheritic pharyngitis and esophagitis caused by Streptocara incognita in three female mute swans (Cygnus olor) in Bosnia and Herzegovina. Prior to death, the swans were showing signs of lethargy, anorexia, and reluctance to move. At necropsy, in all swans severe diphtheritic pharyngitis and esophagitis with deep, dark red hemorrhagic ulcerations were observed. Numerous thin, white, up to 1-cm-long nematodes, identified as S. incognita, were observed embedded in the pharyngeal and esophageal mucosa under the diphtheritic membranes. Histopathology revealed severe fibrinonecrotic inflammation with numerous cross-sections of the parasites. To the authors' knowledge, this is the first report of severe, fatal streptocariasis in mute swans.

  11. Heavy metals (copper, cadmium, lead, mercury) in mute swans from Denmark

    Energy Technology Data Exchange (ETDEWEB)

    Elvestad, K.; Karlog, O.; Clausen, B.

    1982-03-01

    During the severe winter of 1978-79, large numbers of mute swans died in coastal areas of Denmark. Of these, 2111 were collected for examination. The analyses confirm previous findings of relatively high copper levels in mute swans (mean for 178 livers was 2680 mg/kg dry weight (Dw) and for 110 kidneys 34 mg/kg Dw) (Table I, Fig. 1). The copper content was not related to sex or age (Table II). The highest liver levels of copper were found in swans from Western Jutland. Cadmium was found at the same relatively low levels as recorded for waterfowl elsewhere (mean for 178 livers was 12 mg/kg Dw, for 110 kidneys 24 mg/kg Dw) (Table I, Fig. 2). The cadmium content was not sex-related, but it increased with age (Table II). The mean mercury content (liver) was 1.4 mg/kg Dw in the 10 birds analysed (Table I). The mean lead content was 15 mg/kg Dw in the 178 livers analysed and 31 mg/kg Dw in 110 sternum (Table I and Fig. 3). The lead content was not sex-related. In sternum, but not in livers, it was related to age (Table II). One third of the swans were found lead-contaminated probably after ingestion of lead pellets. None of the swans carried high levels of both copper, cadmium, and lead (Table III).

  12. Toxicity of lead-contaminated sediment to mute swans

    Science.gov (United States)

    Day, D.D.; Beyer, W.N.; Hoffman, D.J.; Morton, Alexandra; Sileo, L.; Audet, D.J.; Ottinger, M.A.

    2003-01-01

    Most ecotoxicological risk assessments of wildlife emphasize contaminant exposure through ingestion of food and water. However, the role of incidental ingestion of sediment-bound contaminants has not been adequately appreciated in these assessments. This study evaluates the toxicological consequences of contamination of sediments with metals from hard-rock mining and smelting activities. Lead-contaminated sediments collected from the Coeur d'Alene River Basin in Idaho were combined with either a commercial avian maintenance diet or ground rice and fed to captive mute swans (Cygnus olor) for 6 weeks. Experimental treatments consisted of maintenance or rice diets containing 0, 12 (no rice group), or 24% highly contaminated (3,950 ug/g lead) sediment or 24% reference (9.7 ug/g lead) sediment. Although none of the swans died, the group fed a rice diet containing 24% lead-contaminated sediment were the most severely affected, experiencing a 24% decrease in mean body weight, including three birds that became emaciated. All birds in this treatment group had nephrosis; abnormally dark, viscous bile; and significant (p < 0.05) reductions in hematocrit and hemoglobin concentrations compared to their pretreatment levels. This group also had the greatest mean concentrations of lead in blood (3.2 ug/g), brain (2.2 ug/g), and liver (8.5 ug/g). These birds had significant (alpha = 0.05) increases in mean plasma alanine aminotransferase activity, cholesterol, and uric acid concentrations and decreased plasma triglyceride concentrations compared to all other treatment groups. After 14 days of exposure, mean protoporphyrin concentrations increased substantially, and mean delta-aminolevulinic acid dehydratase activity decreased by more than 95% in all groups fed diets containing highly contaminated sediments. All swans fed diets that contained 24% lead-contaminated sediment had renal acid-fast intranuclear inclusion bodies, which are diagnostic of lead poisoning in waterfowl. Body

  13. The ecology and age structure of a highly pathogenic avian influenza virus outbreak in wild mute swans.

    Science.gov (United States)

    Pybus, O G; Perrins, C M; Choudhury, B; Manvell, R J; Nunez, A; Schulenburg, B; Sheldon, B C; Brown, I H

    2012-12-01

    The first UK epizootic of highly pathogenic (HP) H5N1 influenza in wild birds occurred in 2008, in a population of mute swans that had been the subject of ornithological study for decades. Here we use an innovative combination of ornithological, phylogenetic and immunological approaches to investigate the ecology and age structure of HP H5N1 in nature. We screened samples from swans and waterbirds using PCR and sequenced HP H5N1-positive samples. The outbreak's origin was investigated by linking bird count data with a molecular clock analysis of sampled virus sequences. We used ringing records to reconstruct the age-structure of outbreak mortality, and we estimated the age distribution of prior exposure to avian influenza. Outbreak mortality was low and all HP H5N1-positive mute swans in the affected population were <3 years old. Only the youngest age classes contained an appreciable number of individuals with no detectable antibody responses to viral nucleoprotein. Phylogenetic analysis indicated that the outbreak strain circulated locally for ~1 month before detection and arrived when the immigration rate of migrant waterbirds was highest. Our data are consistent with the hypothesis that HP H5N1 epizootics in wild swans exhibit limited mortality due to immune protection arising from previous exposure. Our study population may represent a valuable resource for investigating the natural ecology and epidemiology of avian influenza.

  14. Antibody Prevalence of Select Arboviruses in Mute Swans (Cygnus olor) in the Great Lakes Region and Atlantic Coast of the United States

    Science.gov (United States)

    Pedersen, Kerri; Marks, David R.; Arsnoe, Dustin M.; Bevins, Sarah N.; Wang, Eryu; Weaver, Scott C.; Mickley, Randall M.; DeLiberto, Thomas J.

    2014-01-01

    Mute swans (Cygnus olor) are an invasive species in the United States. The dramatic increase in their populations in localized areas has led to various problems, among them competition with native species and attacks on humans by aggressive swans. However, very little is known about the ability of these swans to transmit pathogens to humans, domestic birds, or wildlife or participate in enzootic maintenance. To learn more about select pathogens that mute swans may harbor, a survey was conducted from April of 2011 to August of 2012 in the Great Lakes region and localized areas of the Atlantic coast, which revealed serologic evidence of arbovirus exposure in mute swans. Of 497 mute swans tested, antibodies were detected for eastern equine encephalitis (4.8%), St. Louis encephalitis (1.4%), West Nile (1.2%), and Turlock (0.6%) viruses. Samples were also tested for evidence of antibodies to La Crosse virus, but none were positive. PMID:25266351

  15. Influenza A virus H5-specific antibodies in mute swans (Cygnus olor) in the USA.

    Science.gov (United States)

    Kistler, Whitney M; Stallknecht, David E; Lebarbenchon, Camille; Pedersen, Kerri; Marks, David R; Mickley, Randy; DeLiberto, Thomas J; Yabsley, Michael J

    2015-04-01

    The use of serologic assays for influenza A virus (IAV) surveillance in wild birds has increased because of the availability of commercial enzyme-linked immunosorbent assays (ELISAs). Recently, an H5-specific blocking ELISA (bELISA) was shown to reliably detect H5-specific antibodies to low- and high-pathogenic H5 viruses in experimentally infected waterfowl. Mute Swans (Cygnus olor) were frequently associated with highly pathogenic H5N1 outbreaks in Europe and may have a similar role if highly pathogenic H5N1 is introduced into North America. We measured the prevalence of antibodies to the nucleoprotein and H5 protein in Mute Swans using three serologic assays. We collected 340 serum samples from Mute Swans in Michigan, New Jersey, New York, and Rhode Island, US. We detected antibodies to the IAV nucleoprotein in 66.2% (225/340) of the samples. We detected H5-specific antibodies in 62.9% (214/340) and 18.8% (64/340) using a modified H5 bELISA protocol and hemagglutination inhibition (HI) assay, respectively. The modified H5 bELISA protocol detected significantly more positive samples than did the manufacturer's protocol. We also tested 46 samples using virus neutralization. Neutralization results had high agreement with the modified H5 bELISA protocol and detected a higher prevalence than did the HI assay. These results indicate that North American Mute Swans have high nucleoprotein and H5 antibody prevalences.

  16. Widespread avian bornavirus infection in mute swans in the Northeast United States

    Directory of Open Access Journals (Sweden)

    Payne SL

    2012-07-01

    Full Text Available Jianhua Guo,1 Lina Covaleda,1 J Jill Heatley,1 John A Baroch,2 Ian Tizard1, Susan L Payne,11Texas A&M University, College Station, TX, USA; 2USDA/APHIS Wildlife Services, Fort Collins, CO, USAAbstract: Avian bornavirus (ABV matrix (M genes were detected by RT-PCR on brain tissue obtained from 192 mute swans harvested from several Northeastern states. A RT-PCR product was detected in 45 samples. Sequencing of the PCR products confirmed the presence of ABV belonging to the ‘goose’ genotype. The prevalence of positive samples ranged from 28% in Michigan to 0% in northern New York State. Two Rhode Island isolates were cultured. Their M, N, and X-P gene sequences closely matched recently published sequences from Canada geese.Keywords: avian bornavirus, proventricular dilatation disease, reverse transcription, polymerase chain reaction, mute swans

  17. Copper storage in the liver of the wild mute swan (Cygnus olor). Its possible relation to pollution of harbor waters by antifouling paints.

    Science.gov (United States)

    Molnar, J J

    1983-12-01

    Postmortem examination of three wild mute swans (Cygnus olor) from a harbor area disclosed an unusual black discoloration of the liver. Chemical, histochemical, and microscopic studies, along with electron-probe microanalysis, showed that cytoplasmic pigment granules in the liver cells contained a copper-protein complex. Similar findings have been reported in Danish and English studies on large numbers of wild mute swans. Two control mute swans from The Bronx Zoo had negligible amounts of hepatic copper. The striking difference between the wild and the captive swans in hepatic copper content suggests that the copper in the wild swans was of environmental origin, most likely from copper-rich antifouling paint used extensively in the marine industry. Flakes of this paint may be ingested by swans searching for food in the sediment of harbor waters.

  18. Short report: Antibody prevalence of select arboviruses in mute swans (Cygnus olor) in the Great Lakes region and Atlantic coast of the United States.

    Science.gov (United States)

    Pedersen, Kerri; Marks, David R; Arsnoe, Dustin M; Bevins, Sarah N; Wang, Eryu; Weaver, Scott C; Mickley, Randall M; DeLiberto, Thomas J

    2014-12-01

    Mute swans (Cygnus olor) are an invasive species in the United States. The dramatic increase in their populations in localized areas has led to various problems, among them competition with native species and attacks on humans by aggressive swans. However, very little is known about the ability of these swans to transmit pathogens to humans, domestic birds, or wildlife or participate in enzootic maintenance. To learn more about select pathogens that mute swans may harbor, a survey was conducted from April of 2011 to August of 2012 in the Great Lakes region and localized areas of the Atlantic coast, which revealed serologic evidence of arbovirus exposure in mute swans. Of 497 mute swans tested, antibodies were detected for eastern equine encephalitis (4.8%), St. Louis encephalitis (1.4%), West Nile (1.2%), and Turlock (0.6%) viruses. Samples were also tested for evidence of antibodies to La Crosse virus, but none were positive. © The American Society of Tropical Medicine and Hygiene.

  19. Cardiac filariosis in migratory Mute swans (Cygnus olor in Sicily

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    Claudia Manno

    2016-09-01

    Full Text Available Sarconema eurycerca is a common parasitic disease of North America swans and geese. The infection has been correlated with severe heart lesions, often resulting in cardiac failure and death of the animals. Heartworms infections have been previously reported in European swans, and specifically in the United Kingdom and Nederland. Both the countries are characterized by a cold temperate weather, similar to the one that can be found in swan wintering areas of U.S.A. and Canada. The first record of cardiac filariasis associated with Sarconema eurycerca infection in four swans in Italy. Twelve mute swans were examined during avian influenza surveillance activities on migratory birds. Birds were collected in the year 2006, in wintering areas of Eastern Sicily (Italy. Four of the twelve swans showed necrotic-haemorrhagic myocarditis with intra-lesional nematodes. Morphological characteristics identified the parasite as a filarial nematode. Birds lungs samples were used for parasites DNA extraction. The latter was used as template for polymerase chain reaction (PCR amplification and sequencing of part of the 12S rDNA gene. Comparison of genomic DNA extracted from a reference S. eurycerca isolate confirmed parasite identity and provided the first sequence resources for this species of value to future diagnostic and epidemiological studies.

  20. The response of mute swans (Cygnus olor, Gm. 1789) to vaccination against avian influenza with an inactivated H5N2 vaccine.

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    Dolka, Beata; Żbikowski, Artur; Dolka, Izabella; Szeleszczuk, Piotr

    2016-10-22

    Recent epidemics of highly pathogenic avian influenza (HPAI) produced an unprecedented number of cases in mute swans (Cygnus olor) in European countries, which indicates that these birds are very sensitive to the H5N1 virus. The HPAI outbreaks stirred a debate on the controversial stamping-out policy in populations of protected bird species. After preventive vaccination had been approved in the European Union, several countries have introduced vaccination schemes to protect poultry, captive wild birds or exotic birds in zoos against HPAI. The aim of this study was to investigate the immune response of wild mute swans to immunization with an inactivated AI H5N2 vaccine approved for use in poultry. The serological responses of mute swans were assessed by comparison with racing pigeons (Columba livia), a species which is characterized by different susceptibility to infection with the H5N1 HPAI virus and plays a questionable role in the ecology of influenza (H5N1) viruses. Swans were vaccinated once or twice at an interval of 4 weeks. The humoral immune response was evaluated by hemagglutination inhibition (HI) and NP-ELISA. The lymphocyte blast transformation test was used to determine the cell-mediated immune response. Higher values of the geometric mean titer (GMT) and 100 % seroconversion (HI ≥32) were noted in double vaccinated swans (1448.2) than in single vaccinated swans (128.0) or in double vaccinated pigeons (215.3). Significant differences in HI titers were observed between swans and pigeons, but no variations in ELISA scores were noted after the booster dose. Immunization of swans had no effect on the proliferative activity of lymphocytes. The inactivated H5N2 vaccine was safe and immunogenic for mute swans and pigeons. Vaccination may have practical implications for swans kept in zoos, wildlife parks or rehabilitation centers. However, challenge studies are needed to prove the efficacy of the H5N2 AI vaccine.

  1. Acute toxicity and sublethal effects of white phosphorus in mute swans, Cygnus olor

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    Sparling, D.W.; Day, D.; Klein, P.

    1999-01-01

    Among the waterfowl affected by white phosphorus (P4) at a military base in Alaska are tundra (Cygnus columbianus) and trumpeter (C. buccinator) swans. To estimate the toxicity of P4 to swans and compare the toxic effects to those of mallards (Anas platyrhynchos), we dosed 30 juvenile mute swans (C. olor) with 0 to 5.28 mg P4 /kg body weight. The estimated LD50 was 3.65 mg/kg (95% CI: 1.40 to 4.68 mg/kg). However, many of the swans still had P4 in their gizzards after dying, as determined by 'smoking gizzards', and a lower LD50 might be calculated if all of the P4 had passed into the small intestines. We attribute the retention of P4 in swans to the presence of coarse sandlike particles of grit which were of similar size as the P4 pellets. Most swans took 1 to 4.5 days to die in contrast to the few hours normally required in mallards and death appeared to related more to liver dysfunction than to hemolysis. White phosphorus affected several plasma constituents, most notably elevated aspartate amiontransferase, blood urea nitrogen, lactate dehydrogenase, and alanine aminotransferase.

  2. Avian paramyxovirus serotype 1 (Newcastle disease virus), avian influenza virus, and Salmonella spp. in mute swans (Cygnus olor) in the Great Lakes region and Atlantic Coast of the United States.

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    Pedersen, Kerri; Marks, David R; Arsnoe, Dustin M; Afonso, Claudio L; Bevins, Sarah N; Miller, Patti J; Randall, Adam R; DeLiberto, Thomas J

    2014-03-01

    Since their introduction to the United States in the late 19th century, mute swans (Cygnus olor) have become a nuisance species by causing damage to aquatic habitats, acting aggressively toward humans, competing with native waterfowl, and potentially transmitting or serving as a reservoir of infectious diseases to humans and poultry. In an effort to investigate their potential role as a disease reservoir and to establish avian health baselines for pathogens that threaten agricultural species or human health, we collected samples from 858 mute swans and tested them for avian paramyxovirus serotype 1 (APMV-1), avian influenza virus (AIV), and Salmonella spp. when possible. Our results indicate that exposure to APMV-1 and AIV is common (60%, n = 771, and 45%, n = 344, antibody prevalence, respectively) in mute swans, but detection of active viral shedding is less common (8.7%, n = 414, and 0.8%, n = 390, respectively). Salmonella was isolated from three mute swans (0.6%, n = 459), and although the serovars identified have been implicated in previous human outbreaks, it does not appear that Salmonella is commonly carried by mute swans.

  3. Trace Elements (Pb, Zn, Cu in Blood of Mute Swan (Cygnus olor from the Isonzo River Nature Reserve (Italy

    Directory of Open Access Journals (Sweden)

    G Isani*, M Cipone, G Andreani, E Carpenè, E Ferlizza, K Kravos1 and F Perco1

    2013-11-01

    Full Text Available Lead concentrations in blood of 45 specimens of mute swan from the molting area of the Isonzo River Mouth Nature Reserve (Italy were determined in two consecutive years (2006-2007, some birds were neck ringed to identify their homing behavior. The second sampling included whole body X-ray radiography and Cu and Zn plasma analyses to investigate the health impact of putative Pb exposure. X-ray images of all investigated specimens did not show any radiopacity due to the ingestion of metal bodies. Lead levels (0.08-0.44 g/ml were in the range of those reported for swans living in unpolluted or slightly polluted environments and excluded acute intoxication, as confirmed by clinical investigation. Zinc concentrations ranged between 2.93 and 7.59 g/ml and were one order of magnitude higher than Cu concentrations (0.21-0.42 g/ml. The negative correlation between Pb and Zn concentrations could be indicative of adverse health effects caused by chronic lead exposure. To our knowledge this is the first study reporting Pb, Zn and Cu blood levels, X-ray radiographies and data on the origin of swan populations.

  4. Chronic lead poisoning in a herd of mute swans

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, V.R.; Hunt, A.E.; French, M.C.

    1979-01-01

    Lead poisoning due to the ingestion of lead fishing shot was shown to be the cause of death of a number of mute swans Cygnus olor Gmelin. The area in which they were feeding was shown to be heavily contaminated with fishing shot. The results of clinical, histopathological, haematological and analytical examinations are reported. The kidneys of the dead birds contained from 350 to 6650 ..mu..g/g DM of lead and blood lead levels in the remainder of the herd were greatly elevated, rising to 3290 ..mu..g/100 ml. Consistently elevated liver levels of iron and zinc and a marked loss of body weight were all directly proportional to the increase in kidney lead concentration. 17 references, 10 figures, 4 tables.

  5. Computed tomography of coxofemoral injury in five mute swans (Cygnus olor).

    Science.gov (United States)

    Gumpenberger, Michaela; Scope, Alexandra

    2012-10-01

    Five mute swans (Cygnus olor) were presented with inability to stand or with abnormal positioning of a leg. Clinical examinations indicated the possibility of femoral fractures or coxofemoral luxations. The suspected diagnosis was proven by means of computed tomography (CT), while superimposition of gastrointestinal contents or other artefacts limited radiographic diagnosis in three birds. A typical CT sign for lesions of the coxofemoral joint apart from femoral displacement was haemorrhage within the pelvic bones (especially around the acetabulum), found in four of the five birds. Small femoral head avulsion fractures could be detected only with CT.

  6. Toxicity of Anacostia River, Washington, DC, USA, sediment fed to mute swans (Cygnus olor)

    Science.gov (United States)

    Beyer, W.N.; Day, D.; Melancon, M.J.; Sileo, L.

    2000-01-01

    Sediment ingestion is sometimes the principal route by which waterfowl are exposed to environmental contaminants, and at severely contaminated sites waterfowl have been killed by ingesting sediment. Mute swans (Cygnus olor) were fed a diet for six weeks with a high but environmentally realistic concentration (24%) of sediment from the moderately polluted Anacostia River in the District of Columbia, to estimate the sediment?s toxicity. Control swans were fed the same diet without the sediment. Five organochlorine compounds were detected in the treated diets but none of 22 organochlorine compounds included in the analyses were detected in livers of the treated swans. The concentrations of 24 polynuclear aromatic hydrocarbons measured in the treated diet were as high as 0.80 mg/kg and they were thought to have been responsible for the observed induction of hepatic microsomal monooxygenase activity in livers. A concentration of 85 mg/kg of lead in the diet was enough to decrease red blood cell ALAD activity but was not high enough to cause more serious effects of lead poisoning. The dietary concentrations of Al, Fe, V, and Ba were high compared to the concentrations of these elements known to be toxic in laboratory feeding studies, but these elements did not accumulate in the livers of the treated swans and probably were not readily available in the sediment. Although ingestion of the Anacostia River sediment caused subtle toxicological effects in swans, we concluded from pathological examinations and weight data that the treated swans remained basically healthy.

  7. Toxicity of Anacostia River, Washington, DC, USA, sediment fed to mute swans (Cygnus olor)

    Energy Technology Data Exchange (ETDEWEB)

    Beyer, W.N.; Day, D.; Melancon, M.J.; Sileo, L.

    2000-03-01

    Sediment ingestion is sometimes the principal route by which waterfowl are exposed to environmental contaminants, and at severely contaminated sites waterfowl have been killed by ingesting sediment. Mute swans (Cygnus olor) were fed a diet for 6 weeks with a high but environmentally realistic concentration (24%) of sediment from the moderately polluted Anacostia River in the District of Columbia, USA, to estimate the sediment's toxicity. Control swans were fed the same diet without the sediment. Five organochlorine compounds were detected in the treated diets, but none of 22 organochlorine compounds included in the analyses was detected in livers of the treated swans. The concentrations of 24 polynuclear aromatic hydrocarbons measured in the treated diet were as high as 0.80 mg/kg, and they were thought to have been responsible for the observed induction of hepatic microsomal monooxygenase activity in livers. A concentration of 85 mg/kg of lead in the diet was enough to decrease red blood cell ALAD activity but was not high enough to cause more serious effects of lead poisoning. The dietary concentrations of Al, Fe, V, and Ba were high compared to the concentrations of these elements known to be toxic in laboratory feeding studies. However, the lack of accumulation in the livers of the treated swans suggested that these elements were not readily available from the ingested sediment. The authors did not study all potential toxic effects, but, on the basis of those that they did consider, they concluded that the treated swans were basically healthy after a chronic exposure to the sediment.

  8. Pathology of natural infections by H5N1 highly pathogenic avian influenza virus in mute (Cygnus olor) and whooper (Cygnus cygnus) swans.

    Science.gov (United States)

    Teifke, J P; Klopfleisch, R; Globig, A; Starick, E; Hoffmann, B; Wolf, P U; Beer, M; Mettenleiter, T C; Harder, T C

    2007-03-01

    Mortality in wild aquatic birds due to infection with highly pathogenic avian influenza viruses (HPAIV) is a rare event. During the recent outbreak of highly pathogenic avian influenza in Germany, mortality due to H5N1 HPAIV was observed among mute and whooper swans as part of a rapid spread of this virus. In contrast to earlier reports, swans appeared to be highly susceptible and represented the mainly affected species. We report gross and histopathology and distribution of influenza virus antigen in mute and whooper swans that died after natural infection with H5N1 HPAIV. At necropsy, the most reliable lesions were multifocal hemorrhagic necrosis in the pancreas, pulmonary congestion and edema, and subepicardial hemorrhages. Major histologic lesions were acute pancreatic necrosis, multifocal necrotizing hepatitis, and lymphoplasmacytic encephalitis with neuronal necrosis. Adrenals displayed consistently scattered cortical and medullary necrosis. In spleen and Peyer's patches, mild lymphocyte necrosis was present. Immunohistochemical demonstration of HPAIV nucleoprotein in pancreas, adrenals, liver, and brain was strongly consistent with histologic lesions. In the brain, a large number of neurons and glial cells, especially Purkinje cells, showed immunostaining. Occasionally, ependymal cells of the spinal cord were also positive. In the lungs, influenza virus antigen was identified in a few endothelial cells but not within pneumocytes. The infection of the central nervous system supports the view that the neurotropism of H5N1 HPAIV leads to nervous disturbances with loss of orientation. More investigations are necessary to clarify the mechanisms of the final circulatory failure, lung edema, and rapid death of the swans.

  9. Total intravenous anaesthesia by boluses or by continuous rate infusion of propofol in mute swans (Cygnus olor).

    Science.gov (United States)

    Müller, Kerstin; Holzapfel, Judith; Brunnberg, Leo

    2011-07-01

    To investigate intravenous (IV) propofol given by intermittent boluses or by continuous rate infusion (CRI) for anaesthesia in swans. Prospective randomized clinical study. Twenty mute swans (Cygnus olor) (eight immature and 12 adults) of unknown sex undergoing painless diagnostic or therapeutic procedures. Induction of anaesthesia was with 8 mg kg(-1) propofol IV. To maintain anaesthesia, ten birds (group BOLI) received propofol as boluses, whilst 10 (group CRI) received propofol as a CRI. Some physiological parameters were measured. Anaesthetic duration was 35 minutes. Groups were compared using Mann-Whitney U-test. Results are median (range). Anaesthetic induction was smooth and tracheal intubation was achieved easily in all birds. Bolus dose in group BOLI was 2.9 (1.3-4.3) mg kg(-1); interval between and number of boluses required were 4 (1-8) minutes and 6 (4-11) boluses respectively. Total dose of propofol was 19 (12.3-37.1) mg kg(-1). Awakening between boluses was very abrupt. In group CRI, propofol infusion rate was 0.85 (0.8-0.9) mg kg(-1) minute(-1), and anaesthesia was stable. Body temperature, heart and respiratory rates, oxygen saturation (by pulse oximeter) and reflexes did not differ between groups. Oxygen saturations (from pulse oximeter readings) were low in some birds. Following anaesthesia, all birds recovered within 40 minutes. In 55% of all, transient signs of central nervous system excitement occurred during recovery. 8 mg kg(-1) propofol appears an adequate induction dose for mute swans. For maintenance, a CRI of 0.85 mg kg(-1) minute(-1) produced stable anaesthesia suitable for painless clinical procedures. In contrast bolus administration, was unsatisfactory as birds awoke very suddenly, and the short intervals between bolus requirements hampered clinical procedures. Administration of additional oxygen throughout anaesthesia might reduce the incidence of low arterial haemoglobin saturation. © 2011 The Authors. Veterinary Anaesthesia and

  10. Role of manganese oxides in the exposure of mute swans (Cygnus olor) to Pb and other elements in the Chesapeake Bay, USA

    International Nuclear Information System (INIS)

    Beyer, W. Nelson; Day, Daniel

    2004-01-01

    The aims of this study are to estimate exposure of waterfowl to elements in contaminated sediments in the Chesapeake Bay and to consider the potential role of Mn in influencing bioavailability and exposure. Metal concentrations were measured in livers and digesta taken from mute swans living on the Aberdeen Proving Ground, whose sediment had elevated concentrations of Cu, S, Se, Zn, As, Co, Cr, Hg and Pb. Concentrations of only the first four of these elements were elevated in swan digesta. None of the concentrations detected in the digesta or livers of the swans was considered toxic, although the concentrations of Cu and Se were high compared to concentrations of these elements reported in other waterfowl. Lead was found to be scavenged by Mn and Fe oxides from the water and deposited on the surface of vegetation at a reference site. Under some environmental chemical conditions, this is an important route of exposure to Pb in waterfowl, not previously recognized. - Lead was scavenged by Mn and Fe oxides and deposited on aquatic vegetation

  11. Role of manganese oxides in the exposure of mute swans (Cygnus olor) to Pb and other elements in the Chesapeake Bay, USA

    Energy Technology Data Exchange (ETDEWEB)

    Beyer, W. Nelson; Day, Daniel

    2004-05-01

    The aims of this study are to estimate exposure of waterfowl to elements in contaminated sediments in the Chesapeake Bay and to consider the potential role of Mn in influencing bioavailability and exposure. Metal concentrations were measured in livers and digesta taken from mute swans living on the Aberdeen Proving Ground, whose sediment had elevated concentrations of Cu, S, Se, Zn, As, Co, Cr, Hg and Pb. Concentrations of only the first four of these elements were elevated in swan digesta. None of the concentrations detected in the digesta or livers of the swans was considered toxic, although the concentrations of Cu and Se were high compared to concentrations of these elements reported in other waterfowl. Lead was found to be scavenged by Mn and Fe oxides from the water and deposited on the surface of vegetation at a reference site. Under some environmental chemical conditions, this is an important route of exposure to Pb in waterfowl, not previously recognized. - Lead was scavenged by Mn and Fe oxides and deposited on aquatic vegetation.

  12. Highly pathogenic avian influenza virus subtype H5N1 in mute swans (Cygnus olor) in Central Bosnia.

    Science.gov (United States)

    Goletić, Teufik; Gagić, Abdulah; Residbegović, Emina; Kustura, Aida; Kavazović, Aida; Savić, Vladimir; Harder, Timm; Starick, Elke; Prasović, Senad

    2010-03-01

    In order to determine the actual prevalence of avian influenza viruses (AIVs) in wild birds in Bosnia and Herzegovina, extensive surveillance was carried out between October 2005 and April 2006. A total of 394 samples representing 41 bird species were examined for the presence of influenza A virus using virus isolation in embryonated chicken eggs, PCR, and nucleotide sequencing. AIV subtype H5N1 was detected in two mute swans (Cygnus olor). The isolates were determined to be highly pathogenic avian influenza (HPAI) virus and the hemagglutinin sequence was closely similar to A/Cygnus olor/Astrakhan/ Ast05-2-10/2005 (H5N1). This is the first report of HPAI subtype H5N1 in Bosnia and Herzegovina.

  13. A review of lead poisoning in swans

    Science.gov (United States)

    Blus, L.J.

    1994-01-01

    Nearly 10,000 swans of six species or subspecies from 14 countries have died from poisoning caused by lead that originated from ingestion of fishing weights, shotgun pellets (shot), or contaminated vegetation or sediments associated with mining and smelting wastes. Lead contamination in mute swans in England caused local population declines during the late 1970s and 1980s. More tundra swans died from lead poisoning than any other species. The extreme record involved an estimated 7200 tundra swans that died over five winters at one locality in North Carolina. The recent legislation to ban lead fishing weights in most of England and Wales and recent replacement of lead shot with steel shot for waterfowl hunting in the United States and a few areas of Europe, including Denmark, are expected to reduce the incidence of lead poisoning in swans.

  14. T-cell responses in oiled guillemots and swans in a rehabilitation setting.

    Science.gov (United States)

    Troisi, Gera M

    2013-07-01

    Aquatic birds are commonly affected by oil spills. Despite rehabilitation efforts, the majority of rehabilitated common guillemots (Uria aalge) do not survive, whereas mute swans (Cygnus olor) tend to have higher postrelease survival. Polyaromatic hydrocarbons (PAHs) present in crude oil and diesel are immunotoxic in birds affecting cell-mediated responses to immunogens. Because it is a target of PAH toxicity, T-lymphocyte response to controlled mitogen administration (phytohemagglutinnin test) was investigated in a scoping study as a potentially useful minimally invasive in vivo test of cell-mediated immunity. The test was performed on 69 mute swans and 31 common guillemots stranded on the Norfolk and Lincolnshire coastline and inland waterways in England (UK) either due to injury or to contamination with crude or diesel oil. T-lymphocyte response was significantly decreased in swans with greater oil scores. T-lymphocyte responses were also decreased in guillemots, but this finding was not statistically significant.

  15. Pathology and diagnosis of avian bornavirus infection in wild Canada geese (Branta canadensis), trumpeter swans (Cygnus buccinator) and mute swans (Cygnus olor) in Canada: a retrospective study.

    Science.gov (United States)

    Delnatte, Pauline; Ojkic, Davor; Delay, Josepha; Campbell, Doug; Crawshaw, Graham; Smith, Dale A

    2013-04-01

    Nine hundred and fifty-five pathology cases collected in Ontario between 1992 and 2011 from wild free-ranging Canada geese, trumpeter swans and mute swans were retrospectively evaluated for the pathology associated with avian bornavirus (ABV) infection. Cases were selected based on the presence of upper gastrointestinal impaction, central nervous system histopathology or clinical history suggestive of ABV infection. The proportion of birds meeting at least one of these criteria was significantly higher at the Toronto Zoo (30/132) than elsewhere in Ontario (21/823). Central, peripheral and autonomic nervous tissues were examined for the presence of lymphocytes and plasma cells on histopathology. The presence of virus was assessed by immunohistochemistry and reverse transcriptase-polymerase chain reaction (RT-PCR) on frozen brains and on formalin-fixed paraffin-embedded tissues. Among selected cases, 86.3% (44/51) were considered positive on histopathology, 56.8% (29/51) were positive by immunohistochemistry, and RT-PCR was positive on 88.2% (15/17) of the frozen brains and 78.4% (40/51) of the formalin-fixed paraffin-embedded samples. Histopathological lesions included gliosis and lymphoplasmacytic perivascular cuffing in brain (97.7%), spinal cord (50%), peripheral nerves (55.5%) and myenteric ganglia or nerves (62.8%), resembling lesions described in parrots affected with proventricular dilatation disease. Partial amino acid sequences of the nucleocapsid gene from seven geese were 100% identical amongst themselves and 98.1 to 100% identical to the waterfowl sequences recently described in the USA. Although ABV has been identified in apparently healthy geese, our study confirmed that ABV can also be associated with significant disease in wild waterfowl species.

  16. The involvement of prolactin in avian molt: the effects of gender and breeding success on the timing of molt in Mute swans (Cygnus olor).

    Science.gov (United States)

    Dawson, A; Perrins, C M; Sharp, P J; Wheeler, D; Groves, S

    2009-04-01

    The aim of the study was to test the hypothesis that decreasing plasma prolactin stimulates or permits the initiation of avian molt. Changes in the concentration of plasma prolactin in Mute swans (Cygnus olor) were compared in non-breeding singletons and breeding pairs. In breeding swans, the onset of molt is delayed compared to non-breeders, and is delayed further in breeding males compared to their female partners. The seasonal decrease in prolactin in non-breeding birds of both sexes started at the end of May and was associated with the initiation of molt 4 weeks later. The decrease in plasma prolactin in incubating females was more pronounced, as a consequence of increased prolactin secretion associated with incubation behavior, but also started at end of May, and was associated the onset of molt 6 weeks later. In breeding males, plasma prolactin increased at the end of May when they started to care for their newly hatched cygnets. Correspondingly, prolactin began to decrease 3-5 weeks later in males than in females. These males started to molt in mid August, at least 4 weeks later than females. It is concluded that molt is related to decreasing plasma prolactin, and is inhibited when plasma prolactin is increasing or high.

  17. Pathobiology of highly pathogenic avian influenza virus (H5N1) infection in mute swans (Cygnus olor).

    Science.gov (United States)

    Pálmai, Nimród; Erdélyi, Károly; Bálint, Adám; Márton, Lázár; Dán, Adám; Deim, Zoltán; Ursu, Krisztina; Löndt, Brandon Z; Brown, Ian H; Glávits, Róbert

    2007-06-01

    The results of pathological, virological and polymerase chain reaction examinations carried out on 35 mute swans (Cygnus olor) that succumbed to a highly pathogenic avian influenza virus (H5N1) infection during an outbreak in Southern Hungary are reported. The most frequently observed macroscopic lesions included: haemorrhages under the epicardium, in the proventricular and duodenal mucosa and pancreas; focal necrosis in the pancreas; myocardial degeneration; acute mucous enteritis; congestion of the spleen and lung, and the accumulation of sero-mucinous exudate in the body cavity. Histopathological lesions comprised: lymphocytic meningo-encephalomyelitis accompanied by gliosis and occasional perivascular haemorrhages; multi-focal myocardial necrosis with lympho-histiocytic infiltration; pancreatitis with focal necrosis; acute desquamative mucous enteritis; lung congestion and oedema; oedema of the tracheal mucosa and, in young birds, the atrophy of the bursa of Fabricius as a result of lymphocyte depletion and apoptosis. The observed lesions and the moderate to good body conditions were compatible with findings in acute highly pathogenic avian influenza infections of other bird species reported in the literature. Skin lesions and lesions typical for infections caused by strains of lower pathogenicity (low pathogenic avian influenza virus) such as emaciation or fibrinous changes in the reproductive and respiratory organs, sinuses and airsacs were not observed. The H5N1 subtype avian influenza virus was isolated in embryonated fowl eggs from all cases and it was identified by classical and molecular virological methods.

  18. Presence of serum antibodies to influenza A subtypes H5 and N1 in swans and ibises in French wetlands, irrespective of highly pathogenic H5N1 natural infection.

    Science.gov (United States)

    Niqueux, Eric; Guionie, Olivier; Schmitz, Audrey; Hars, Jean; Jestin, Véronique

    2010-03-01

    Highly pathogenic (HP) avian influenza A viruses (AIVs) subtype H5N1 (subclade 2.2) were detected in wild birds during outbreaks in France during winter 2006 and summer 2007 in la Dombes wetlands (eastern France) and in Moselle wetlands (northeastern France), respectively. Blood samples from apparently healthy wild birds were collected in 2006 and 2007 from the end of the outbreak to several weeks after the influenza A outbreak inside and outside the contaminated areas, and in 2008 outside the contaminated areas. The samples were tested for the presence and/or quantitation of serum antibodies to influenza A subtypes H5 and N1 using hemagglutination inhibition tests (HITs), a commercial N1-specific enzyme-linked immunosorbent assay kit, and virus neutralization assay. In the HIT, low pathogenicity (LP) and HP H5 AIVs (belonging to H5N1, H5N2, and H5N3 subtypes) were used as antigens. One hundred mute swans were bled in the la Dombes outbreak area in 2006. During 2007, 46 mallards, 69 common pochards, and 59 mute swans were sampled in the Moselle outbreak area. For comparison, blood samples were also collected in 2007 from 60 mute swans from the Marne department where no HP H5N1 influenza A cases have been reported, and in 2008 from 111 sacred ibises in western France where no HP H5N1 influenza A infections in wild birds have been reported either. Mute swans (irrespective of their origin and time of sampling) and sacred ibises (from an area with no known outbreaks) had the highest prevalence of positive sera in the H5 HIT (49-69% and 64%, respectively). The prevalence of anti-H5 antibodies in mallards and common pochards was lower (28% and 27%, respectively). Positive H5- and N1-antibody responses were also significantly associated in swans (irrespective of their origin and time of sampling) and in sacred ibises. However, in swans from the area without outbreaks, the HIT titer against an H5N1 LPAIV was significantly higher than against an H5N1 2.2.1 HPAIV, whereas no

  19. Lead exposure from lead pellets: age-related accumulation in mute swans

    Energy Technology Data Exchange (ETDEWEB)

    Eskildsen, J.; Grandjean, P.

    1984-05-01

    In a cross-sectional study of adult swans and their successfully fledged young in Ringkobing Fjord, West Jutland, Denmark, 128 venous blood samples were taken during the moulting period and analyzed for lead. While the juveniles generally showed blood lead levels below 15 micrograms/100 ml (median, 11 micrograms/100 ml), the values were significantly higher in adults (median, 25 micrograms/100 ml). Adult females showed slightly higher levels than did adult males. None of the birds examined showed signs of acute lead toxicity, and increased blood levels in adults may reflect increased lead body burdens from previous ingestion of lead shot as gizzard stones.

  20. Bird ringing in Slovenia in 2014 and results of the first telemetry study of an African migrant

    Directory of Open Access Journals (Sweden)

    Vrezec Al

    2015-12-01

    Full Text Available In 2014, 162 bird species were recorded during the bird ringing activities in Slovenia. Of 155 species, 62,275 birds were ringed, and 107 recoveries of birds ringed in Slovenia and found abroad, 148 foreign recoveries in Slovenia and 1395 local recoveries were recorded. The most frequently ringed species were Blackcap Sylvia atricapilla and Great Tit Parus major. As far as ringed nestlings are concerned, Great Tits and Barn Swalllows Hirundo rustica predominated. Considering the recoveries ringed of found birds abroad, the commonest were Black-headed Gulls Chroicocephalus ridibundus and Mute Swans Cygnus olor. The farthest recovery was a Barn Swallow Hirundo rustica found in the Democratic Republic of Congo (5171 km away. Among the more interesting finds was also the so far southernmost recovery of a Sand Martin Riparia riparia found in Israel. Let us also mention the first recovery of a Corncrake Crex crex, which bred and was ringed in 2013 at Planinsko polje (central Slovenia and was found in the 2014 breeding season in the Czech Republic. Among rare species, two Little Buntings Emberiza pusilla were caught and ringed. After nine years, the Roller Coracias garrulus bred again in Slovenia in 2014 and its nestlings were ringed. The paper also brings the description of the migration route of the first African migrant, the Black Stork Ciconia nigra, marked with a GPS/GSM telemetric device, which migrated across the Adriatic Sea, Sicily and Sahara to Nigeria.

  1. A novel surgical correction and innovative splint for swan neck deformity in hypermobility syndrome

    Directory of Open Access Journals (Sweden)

    Karthik Vishwanathan

    2018-01-01

    Full Text Available Splinting is a great domain of occupational therapy profession. Making a splint for the patient would depend on the need or requirement of the problems and deformities. Swan neck deformity is an uncommon condition, and it can be seen in rheumatoid arthritis, cerebral palsy, and after trauma. Conservative treatment of the swan neck deformity is available by different static splints only. There are very few reports of surgical correction of swan-neck deformity in benign hypermobility syndrome. This case report describes the result of novel surgical intervention and an innovative hand splint in a 20-year-old female with a history of cardiovascular stroke with no residual neurological deficit. She presented with correctable swan neck deformity and failed to improve with static ring splints to correct the deformity. She underwent volar plate plication of the proximal interphalangeal joint of the left ring finger along with hemitenodesis of ulnar slip of flexor digitorum superficialis (FDS tendon whereby, the ulnar slip of FDS was passed through a small surgically created rent in A2 pulley and sutured back to itself. Postoperatively, the patient was referred to occupational therapy for splinting with the instruction that the splint would work sometimes for as static and some time as dynamic for positional and correction of the finger. After occupational therapy intervention and splinting, the patient had a full correction of the swan-neck deformity with near full flexion of the operated finger and can work independently.

  2. No evidence of transmission of H5N1 highly pathogenic avian influenza to humans after unprotected contact with infected wild swans.

    Science.gov (United States)

    Wallensten, A; Salter, M; Bennett, S; Brown, I; Hoschler, K; Oliver, I

    2010-02-01

    Highly pathogenic avian influenza (HPAI) subtype H5N1 remains a public health threat as long as it circulates in wild and domestic birds. Information on the transmissibility of H5N1 HPAI from wild birds is needed for evidence-based public health advice. We investigated if transmission of H5N1 HPAI had taken place in people that had unprotected contact with infected wild mute swans during an incident at the Abbotsbury Swannery in Dorset, England. Thirteen people who had been exposed to infected swans were contacted and actively followed up for symptoms. Serology was taken after 30 days. We did not find evidence of transmission of H5N1 HPAI to humans during the incident. The incident provided a rare opportunity to study the transmissibility of the virus from wild birds to humans.

  3. Tissue tropism of highly pathogenic avian influenza virus subtype H5N1 in naturally infected mute swans (Cygnus Olor ), domestic geese (Aser Anser var. domestica), pekin ducks (Anas platyrhynchos) and mulard ducks ( Cairina moschata x anas platyrhynchos).

    Science.gov (United States)

    Szeredi, Levente; Dán, Adám; Pálmai, Nimród; Ursu, Krisztina; Bálint, Adám; Szeleczky, Zsófia; Ivanics, Eva; Erdélyi, Károly; Rigó, Dóra; Tekes, Lajos; Glávits, Róbert

    2010-03-01

    The 2006 epidemic due to highly pathogenic avian influenza virus (HPAIV) subtype H5N1 in Hungary caused the most severe losses in waterfowl which were, according to the literature at the time, supposed to be the most resistant to this pathogen. The presence of pathological lesions and the amount of viral antigen were quantified by gross pathology, histopathology and immunohistochemistry (IHC) in the organs of four waterfowl species [mute swans (n = 10), domestic geese (n = 6), mulard ducks (n = 6) and Pekin ducks (n = 5)] collected during the epidemic. H5N1 subtype HPAIV was isolated from all birds examined. Quantitative real-time reverse transcriptase-polymerase chain reaction (qRRT-PCR) was also applied on a subset of samples [domestic geese (n = 3), mulard (n = 4) and Pekin duck (n = 4)] in order to compare its sensitivity with IHC. Viral antigen was detected by IHC in all cases. However, the overall presence of viral antigen in tissue samples was quite variable: virus antigen was present in 56/81 (69%) swan, 22/38 (58%) goose, 28/46 (61%) mulard duck and 5/43 (12%) Pekin duck tissue samples. HPAIV subtype H5N1 was detected by qRRT-PCR in all birds examined, in 19/19 (100%) goose, 7/28 (25%) mulard duck and 12/28 (43%) Pekin duck tissue samples. As compared to qRRTPCR, the IHC was less sensitive in geese and Pekin ducks but more sensitive in mulard ducks. The IHC was consistently positive above 4.31 log10 copies/reaction but it gave very variable results below that level. Neurotropism of the isolated virus strains was demonstrated by finding the largest amount of viral antigen and the highest average RNA load in the brain in all four waterfowl species examined.

  4. 76 FR 77890 - Swan Ranch Railroad, L.L.C.-Operation Exemption-Swan Industrial Park

    Science.gov (United States)

    2011-12-14

    ... DEPARTMENT OF TRANSPORTATION Surface Transportation Board [Docket No. FD 35574] Swan Ranch Railroad, L.L.C.--Operation Exemption--Swan Industrial Park Swan Ranch Railroad, L.L.C. (SRR),\\1\\ a noncarrier, has filed a verified notice of exemption under 49 CFR 1150.31 to operate, pursuant to an agreement with Cheyenne Logistics Hub, LLC (CLH), all...

  5. Chernobyl and the Slimbridge swans

    Energy Technology Data Exchange (ETDEWEB)

    Hancock, R.; Woolam, P.

    1987-11-01

    Radioactivity measurements were carried out on 46 live Bewick swans to determine if they had ingested any of the Chernobyl fallout deposits. The swans migrate each autumn from their breeding grounds in Artic Russia to spend the winter at Slimbridge, United Kingdom. At the time of the Chernobyl accident, the swans were at least 2500 km from Chernobyl. However on their migratory flight in the autumn, the swans would have stopped for several days on the Baltic Sea/North Sea coasts, which are known to be contaminated with fallout from the initial Chernobyl plume. The measurements were made in January 1987 on swans in the Slimbridge area, and the levels of radioactivity were so low that detection was very difficult.

  6. Chernobyl and the Slimbridge swans

    International Nuclear Information System (INIS)

    Hancock, R.; Woolam, P.

    1987-01-01

    Radioactivity measurements were carried out on 46 live Bewick swans to determine if they had ingested any of the Chernobyl fallout deposits. The swans migrate each autumn from their breeding grounds in Artic Russia to spend the winter at Slimbridge, United Kingdom. At the time of the Chernobyl accident, the swans were at least 2500 km from Chernobyl. However on their migratory flight in the autumn, the swans would have stopped for several days on the Baltic Sea/North Sea coasts, which are known to be contaminated with fallout from the initial Chernobyl plume. The measurements were made in January 1987 on swans in the Slimbridge area, and the levels of radioactivity were so low that detection was very difficult. (UK)

  7. Avian bornavirus in free-ranging waterfowl: prevalence of antibodies and cloacal shedding of viral RNA.

    Science.gov (United States)

    Delnatte, Pauline; Nagy, Éva; Ojkic, Davor; Leishman, David; Crawshaw, Graham; Elias, Kyle; Smith, Dale A

    2014-07-01

    We surveyed free-ranging Canada Geese (Branta canadensis), Trumpeter Swans (Cygnus buccinator), Mute Swans (Cygnus olor), and Mallards (Anas platyrhynchos) to estimate the prevalence of antibodies to avian bornavirus (ABV) and of cloacal shedding of ABV RNA in southern Ontario, Canada. Blood samples and cloacal swabs were collected from 206 free-ranging Canada Geese, 135 Trumpeter Swans, 75 Mute Swans, and 208 Mallards at 10 main capture sites between October 2010 and May 2012. Sera were assessed for antibodies against ABV by enzyme-linked immunosorbent assay and swabs were evaluated for ABV RNA using real-time reverse-transcription PCR. Serum antibodies were detected in birds from all four species and at each sampling site. Thirteen percent of the geese caught on the Toronto Zoo site shed ABV RNA in feces compared with 0% in geese sampled at three other locations. The proportions of shedders among Mute Swans, Trumpeter Swans, and Mallards were 9%, 0%, and 0%, respectively. Birds that were shedding viral RNA were more likely to have antibodies against ABV and to have higher antibody levels than those that were not, although many birds with antibodies were not shedding. We confirmed that exposure to, or infection with, ABV is widespread in asymptomatic free-ranging waterfowl in Canada; however, the correlation between cloacal shedding, presence of antibodies, and presence of disease is not fully understood.

  8. Bm-muted, orthologous to mouse muted and encoding a subunit of the BLOC-1 complex, is responsible for the otm translucent mutation of the silkworm Bombyx mori.

    Science.gov (United States)

    Zhang, Haokun; Kiuchi, Takashi; Wang, Lingyan; Kawamoto, Munetaka; Suzuki, Yutaka; Sugano, Sumio; Banno, Yutaka; Katsuma, Susumu; Shimada, Toru

    2017-09-20

    "Tanaka's mottled translucent" (otm) is a mutation of the silkworm Bombyx mori that exhibits translucent skin during larval stages. We performed positional cloning of the gene responsible for otm and mapped it to a 364-kb region on chromosome 5 that contains 22 hypothetical protein-coding genes. We performed RNA-seq analysis of the epidermis and fat body of otm larvae and determined that the gene BGIBMGA002619 may be responsible for the otm mutation. BGIBMGA002619 encodes the biosynthesis of lysosome-related organelles complex 1 (BLOC-1) subunit 5, whose ortholog is responsible for the Muted mutant in mouse. Accordingly, we named this gene Bm-muted. We discovered that the expression of Bm-muted in the epidermis and fat body of otm mutants was dramatically suppressed compared with the wild type. We determined the nucleotide sequences of the full-length cDNA and genomic region corresponding to Bm-muted and found that a 538-bp long DNA sequence similar to B. mori transposon Organdy was inserted into the 3' end of the first intron of Bm-muted in two otm strains. The Bm-muted cDNA of otm mutants lacked exon 2, and accordingly generated a premature stop codon in exon 3. In addition, short interfering RNA (siRNA)-mediated knockdown of this gene caused localized partial translucency of larval skin. These data indicate that the mutation in Bm-muted caused the otm-mutant phenotype. We propose that the insertion of Organdy caused a splicing disorder in Bm-muted in the otm mutant, resulting in a null mutation of Bm-muted. This mutation is likely to cause deficiencies in urate granule formation in epidermal cells that result in translucent larval skin. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Trace element exposure of whooper swans (Cygnus cygnus) wintering in a marine lagoon (Swan Lake), northern China.

    Science.gov (United States)

    Wang, Feng; Xu, Shaochun; Zhou, Yi; Wang, Pengmei; Zhang, Xiaomei

    2017-06-30

    Trace element poisoning remains a great threat to various waterfowl and waterbirds throughout the world. In this study, we determined the trace element exposure of herbivorous whooper swans (Cygnus cygnus) wintering in Swan Lake (Rongcheng), an important swan protection area in northern China. A total of 70 samples including abiotic factors (seawater, sediments), food sources (seagrass, macroalgae), feathers and feces of whooper swans were collected from the marine lagoon during the winters of 2014/2015 and 2015/2016. Concentrations of Cu, Zn, Pb, Cr, Cd, Hg and As were determined to investigate the trace element exposure of whooper swans wintering in the area. Results showed that there was an increasing trend in sediment trace element concentrations, compared with historical data. The trace element concentrations in swan feces most closely resembled those of Zostera marina leaves, especially for Cd and Cr. The Zn and Hg concentrations in the swan feces (49.57 and 0.01mg/kg, respectively) were lower than the minimum values reported in the literature for other waterfowls, waterbirds and terrestrial birds. However, the concentrations of the other five trace elements fell within the lower and mediate range of values reported for birds across the world. These results suggest that the whooper swans wintering in Swan Lake, Rongcheng are not suffering severe trace element exposure; however, with the increasing input of trace elements to the lagoon, severe adverse impacts may occur in the future, and we therefore suggest that the input of trace elements to this area should be curbed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. SWANS: A Prototypic SCALE Criticality Sequence for Automated Optimization Using the SWAN Methodology

    International Nuclear Information System (INIS)

    Greenspan, E.

    2001-01-01

    SWANS is a new prototypic analysis sequence that provides an intelligent, semi-automatic search for the maximum k eff of a given amount of specified fissile material, or of the minimum critical mass. It combines the optimization strategy of the SWAN code with the composition-dependent resonance self-shielded cross sections of the SCALE package. For a given system composition arrived at during the iterative optimization process, the value of k eff is as accurate and reliable as obtained using the CSAS1X Sequence of SCALE-4.4. This report describes how SWAN is integrated within the SCALE system to form the new prototypic optimization sequence, describes the optimization procedure, provides a user guide for SWANS, and illustrates its application to five different types of problems. In addition, the report illustrates that resonance self-shielding might have a significant effect on the maximum k eff value a given fissile material mass can have

  11. SWANS: A Prototypic SCALE Criticality Sequence for Automated Optimization Using the SWAN Methodology

    Energy Technology Data Exchange (ETDEWEB)

    Greenspan, E.

    2001-01-11

    SWANS is a new prototypic analysis sequence that provides an intelligent, semi-automatic search for the maximum k{sub eff} of a given amount of specified fissile material, or of the minimum critical mass. It combines the optimization strategy of the SWAN code with the composition-dependent resonance self-shielded cross sections of the SCALE package. For a given system composition arrived at during the iterative optimization process, the value of k{sub eff} is as accurate and reliable as obtained using the CSAS1X Sequence of SCALE-4.4. This report describes how SWAN is integrated within the SCALE system to form the new prototypic optimization sequence, describes the optimization procedure, provides a user guide for SWANS, and illustrates its application to five different types of problems. In addition, the report illustrates that resonance self-shielding might have a significant effect on the maximum k{sub eff} value a given fissile material mass can have.

  12. Swan-Ganz - right heart catheterization

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003870.htm Swan-Ganz - right heart catheterization To use the sharing features on this page, please enable JavaScript. Swan-Ganz catheterization is the passing of a thin ...

  13. Hiding from swans: optimal burial depth of sago pondweed tubers foraged by Bewick's swans

    NARCIS (Netherlands)

    Santamaría, L.; Rodriguez-Girones, M.A.

    2002-01-01

    1 We used a combination of laboratory and field experiments to test the hypothesis that the burial depth of Potamogeton pectinatus tubers will vary with local sediment type and swan predation pressure. 2 In the field, mortality due to predation by swans decreased linearly with burial depth (from 100

  14. Learning and Self-Stimulation in Mute and Echolalic Autistic Children.

    Science.gov (United States)

    Chock, Patricia N.; Glahn, T. J.

    1983-01-01

    The effects of self-stimulation on task acquisition were studied in three mute low-functioning autistic and three echolic higher-functioning autistic children in multiple-baseline designs. The study found that the echolalic children were able to learn the task without external suppression of their self-stimulation but the mute Ss were not. (CL)

  15. Black-swan events in animal populations

    OpenAIRE

    Anderson, Sean C.; Branch, Trevor A.; Cooper, Andrew B.; Dulvy, Nicholas K.

    2017-01-01

    Black swans?statistically improbable events with profound consequences?happen more often than expected in financial, social, and natural systems. Our work demonstrates the rare but systematic presence of black-swan events in animal populations around the world (mostly birds, mammals, and insects). These events are predominantly downward, implying that unexpected population crashes occur more frequently than increases. Black-swan events are not driven by life history (e.g., lifespan) but by ex...

  16. Black Swans æstetiske kvaliteter

    OpenAIRE

    Nissen, Anna; Sørensen, Line; Clausen, Yunas; Lerche-Jensen, Natascha; van Cuyl Kuylenstierna, Christine; Mikkelsen, Camilla; Kristensen, Trine

    2012-01-01

    Projektet beskæftiger sig med Black Swan i forhold til David Bordwells filmteori og Immanuel Kants æstetikteori, som er behandlet med henblik på at undersøge om disse er kompatible trods tidsspændet. Teorierne er brugt til at analysere Black Swans æstetiske kvaliteter. Grundet metodiske overvejelser er Kants teori om det skønne blevet udvidet til ligeledes at omfatte det hæslige, fordi dette utvivlsomt er en stor del af Black Swan, og det er derved nødvendigt, at vi i vores projekt kan dømme ...

  17. Search paths of swans foraging on spatially autocorrelated tubers

    NARCIS (Netherlands)

    Nolet, B.A.; Mooij, W.M.

    2002-01-01

    1. Tundra swans forage on below-ground pondweed tubers that are heterogeneously distributed in space. The swans have no visual cues to delineate patches. It was tested whether swans employ an area-restricted search tactic. Theory predicts that swans should alternate between an intensive (low-speed,

  18. Tundra swan habitat preferences during migration in North Dakota

    Science.gov (United States)

    Earnst, Susan L.

    1994-01-01

    I studied tundra swan (Cygnus columbianus columbianus) habitat preference in North Dakota during autumn migration, 1988-89. Many thousand tundra swans stop in the Prairie Pothole region during autumn migration, but swan resource use has not been quantified. I examined habitat preference in relation to an index of sago pondweed (Potamogeton pectinatus) presence, extent of open water, and wetland size. I compared habitat preference derived from counts of all swans to those derived from foraging swans only and cygnets only. Foraging swans preferred wetlands with sago pondweed (P = 0.03); the number of foraging swans per wetland was >4 times higher on wetlands with sago pondweed than on wetlands without sago. In contrast, nonforaging swans did not prefer wetlands with sago pondweed (P = 0.85) but preferred large wetlands (P = 0.02) and those with a high proportion of contiguous open water (P feeding than adults (P = 0.03) and occurred proportionately more often in smaller flocks (P = 0.04), but cygnets and adults had similar habitat preferences.

  19. Interviews with Selectively Mute Children

    Science.gov (United States)

    Omdal, Heidi; Galloway, David

    2007-01-01

    The assessment of selective mutism usually takes place in a clinic, where the child often refuses to speak to the therapist. The challenge when trying to understand the child's own perspective is to find a medium for communication. Three selectively mute children were interviewed using Raven's Controlled Projection for Children (RCPC). The…

  20. Can SOHO SWAN Detect CMEs?

    Science.gov (United States)

    St. Cyr, O. C.; Malayeri, M. L.; Yashiro, S.; Quemerais, E.; Bertaux, J.; Howard, R.

    2003-12-01

    We have investigated the possibility that the Solar Wind Anisotropies (SWAN) remote sensing instrument on SOHO may be able to detect coronal mass ejections (CMEs) in neutral Hydrogen Lyman-α emission. We have identified CMEs near the Sun in observations by the SOHO LASCO white-light coronagraphs and in extreme ultraviolet emissions using SOHO EIT. There are very few methods of tracking CMEs after they leave the coronagraph's field-of-view, so this is an important topic to study. The primary science goal of the SWAN investigation is the measurement of large-scale structures in the solar wind, and these are obtained by detecting intensity fluctuations in Lyman-α . SWAN consists of a pair of sensors on opposite panels of SOHO. The instantaneous field-of-view of each sensor unit is a 5° x 5° square, divided into 1° pixels. A gimbaled periscope system allows each sensor to map the intensity distribution of Lyman-α , and the entire sky can be scanned in less than one day. This is the typical mode of operation for this instrument (Bertaux et al., Solar Physics, 162, 403-439, 1995). Beginning in May 2002 the sky-scan mode of the SWAN detectors was interrupted, and they were held stationary for one-or-more 15-hour campaigns each week. During those campaigns the SWAN sensors were positioned above the East or West equator of the Sun at locations chosen to be as close to the Sun as possible (typically 50 solar radii from Sun-center). Based on the LASCO and EIT data, we have identified CMEs whose extrapolated height-time measurements indicated that the events would cross the SWAN field during the campaign period. During 12 months' observation, there were ˜10 CMEs that met two criteria: (1) an event low in the corona near the solar limb could be unambiguously identified in EIT; and (2) the CME could be tracked beyond 20 R⊙ in LASCO C3. We consider these CMEs to be particularly well-observed since the speed measured in LASCO could be reliably extrapolated to the SWAN

  1. Study of Womens Health Across the Nation (SWAN) Data: Investigator Access

    Data.gov (United States)

    U.S. Department of Health & Human Services — The SWAN Coordinating Center provides SWAN data access to SWAN Investigators through the study website. The SWAN website provides access to longitudinal data...

  2. Intervention with the Selectively Mute Child.

    Science.gov (United States)

    Porjes, Michelle D.

    1992-01-01

    Defines selective mutism as describing children who actively choose to speak to few people in selected environments, noting it is most commonly used to describe nonverbal behavior in school setting. Reviews literature from psychoanalytic and learning theory approaches. Presents intervention strategies used with two selectively mute first graders.…

  3. Body size mediated coexistence in swans.

    Science.gov (United States)

    Engelhardt, Katharina A M; Ritchie, Mark E; Powell, James A

    2014-01-01

    Differences in body sizes may create a trade-off between foraging efficiency (foraging gains/costs) and access to resources. Such a trade-off provides a potential mechanism for ecologically similar species to coexist on one resource. We explored this hypothesis for tundra (Cygnus columbianus) and trumpeter swans (Cygnus buccinator), a federally protected species, feeding solely on sago pondweed (Stuckenia pectinata) tubers during fall staging and wintering in northern Utah. Foraging efficiency was higher for tundra swans because this species experienced lower foraging and metabolic costs relative to foraging gains; however, trumpeter swans (a) had longer necks and therefore had access to exclusive resources buried deep in wetland sediments and (b) were more aggressive and could therefore displace tundra swans from lucrative foraging locations. We conclude that body size differentiation is an important feature of coexistence among ecologically similar species feeding on one resource. In situations where resources are limiting and competition for resources is strong, conservation managers will need to consider the trade-off between foraging efficiency and access to resources to ensure ecologically similar species can coexist on a shared resource.

  4. Study of Womens Health Across the Nation (SWAN) Biospecimen Repository

    Data.gov (United States)

    U.S. Department of Health & Human Services — The SWAN Repository is the biospecimen bank of the SWAN study. All stored specimens are from the 3,302 SWAN participants, collected across the 14 clinic visits...

  5. 27 CFR 9.211 - Swan Creek.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Swan Creek. 9.211 Section 9.211 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.211 Swan Creek. (a) Name. The name of the viticultural are...

  6. Letna Dinamika Pojavljanja Vodnih Ptic Na Reki Dravi Med Mariborskim Jezerom In Jezom Melje (Sv Slovenija / Yearly dynamics of waterbirds’ occurrence on the Drava River between Lake Maribor and Melje Dam (NE Slovenia

    Directory of Open Access Journals (Sweden)

    Logar Katja

    2014-11-01

    Full Text Available Between April 2007 and April 2008, 40 systematic waterbird counts were conducted on the Drava River between Lake Maribor and the Melje Dam (length 8.5 km, area 155 ha to determine the specific composition, abundance and seasonal dynamics of bird occurrence. Between October and May, counts were conducted every week, whereas between June and September they were carried out once every two weeks. In total, 26,803 individuals of 30 species were counted. The number of waterbirds and diversity of species were the highest from late December to late February, when more than 1,000 individuals were regularly present in the area. Waterbirds were distributed along the river unequally, with the highest number of birds present yearround in the city centre and in the first counting sector of Lake Maribor. The Mallard Anas platyrhynchos and Mute Swan Cygnus olor were recorded during every count, while occurrence frequency was greater than 50% in another 10 species. Dominant species in terms of percentage composition were Mallard, Black-headed Gull Chroicocephalus ridibundus, Coot Fulica atra, Mute Swan, Pochard Aythya ferina and Tufted Duck Ay. fuligula. Mute Swan and Mallard were the only breeding waterbirds in the study area. Both the total number of waterbirds and the highest daily total in the first two counting sectors were greater between October and March 1992/93 than in our study. The decline in numbers was the greatest for Mallard, Pochard and Tufted Duck, while an increase was noted in Mute Swan and Yellow-legged / Caspian Gull Larus michahellis / cachinnans. The total number of waterbirds and the number of some species in the study area were significantly higher than expected solely based on its length compared to the length of the lowland Drava in Slovenia (125.7 km. The study area is conservationally important for Pochard, Tufted Duck and Black-headed Gull

  7. Annual survival rates of adult and immature eastern population tundra swans

    Science.gov (United States)

    Nichols, J.D.; Bart, J.; Limpert, R.J.; Sladen, William J. L.; Hines, J.E.

    1992-01-01

    Tundra swans (Cygnus columbianus ) of the eastern population were neckbanded in Maryland, North Carolina, and Alaska from 1966 through 1990. These swans were resighted and recaptured during autumn, winter, and spring, 1966-1990. Although the original motivation for this study involved swan movements, we wanted to use the resulting data to test hypotheses about sources of variation in swan survival rates. Recaptures of legbanded and neckbanded swans permitted us to estimate neckband loss rates, which were found to vary with age and sex of swans, and number of years since initial application. Estimates of annual neckband retention rate ranged from about 0.50 for adult male swans greater than or equal to 2 years after initial neckbanding to > 0.96 for immature swans and adult females the first year following neckbanding. This variation in neckband loss rates prevented the simple correction of survival estimates to account for such loss. Consequently, we developed a series of multinomial models parameterized with survival, sighting, and neckband retention probabilities for use with the recapture and resighting data.

  8. Body Size Mediated Coexistence in Swans

    Directory of Open Access Journals (Sweden)

    Katharina A. M. Engelhardt

    2014-01-01

    Full Text Available Differences in body sizes may create a trade-off between foraging efficiency (foraging gains/costs and access to resources. Such a trade-off provides a potential mechanism for ecologically similar species to coexist on one resource. We explored this hypothesis for tundra (Cygnus columbianus and trumpeter swans (Cygnus buccinator, a federally protected species, feeding solely on sago pondweed (Stuckenia pectinata tubers during fall staging and wintering in northern Utah. Foraging efficiency was higher for tundra swans because this species experienced lower foraging and metabolic costs relative to foraging gains; however, trumpeter swans (a had longer necks and therefore had access to exclusive resources buried deep in wetland sediments and (b were more aggressive and could therefore displace tundra swans from lucrative foraging locations. We conclude that body size differentiation is an important feature of coexistence among ecologically similar species feeding on one resource. In situations where resources are limiting and competition for resources is strong, conservation managers will need to consider the trade-off between foraging efficiency and access to resources to ensure ecologically similar species can coexist on a shared resource.

  9. Radioactivity measurements on live Bewick's Swans

    International Nuclear Information System (INIS)

    Hancock, R.; Wollam, P.B.

    1987-01-01

    Measurements made on 46 live swans at Slimbridge using portable high resolution hyperpure germanium gamma ray spectrometry equipment are described. Laboratory measurements are also reported on two swans which died of natural causes or of flying accidents. The implications of the measured radioactivity levels are discussed in relation to the suggestion that they might have been affected by the Chernobyl accident on their migration. (UK)

  10. When is the Swan Knight not the Swan Knight? 

    DEFF Research Database (Denmark)

    Matthews, Alastair

    2017-01-01

    when contextualizing Berthold, describing instead an apparent reworking of the Swan Knight story in Demantin. The article thereby reassesses Berthold’s significance, proposing that research on European literatures would be better able to deal with such authors if it deployed an abstract concept...

  11. Black Swan Tropical Cyclones

    Science.gov (United States)

    Emanuel, K.; Lin, N.

    2012-12-01

    Virtually all assessments of tropical cyclone risk are based on historical records, which are limited to a few hundred years at most. Yet stronger TCs may occur in the future and at places that have not been affected historically. Such events lie outside the realm of historically based expectations and may have extreme impacts. Their occurrences are also often made explainable after the fact (e.g., Hurricane Katrina). We nickname such potential future TCs, characterized by rarity, extreme impact, and retrospective predictability, "black swans" (Nassim Nicholas Taleb, 2007). As, by definition, black swan TCs have yet to happen, statistical methods that solely rely on historical track data cannot predict their occurrence. Global climate models lack the capability to predict intense storms, even with a resolution as high as 14 km (Emanuel et al. 2010). Also, most dynamic downscaling methods (e.g., Bender et al. 2010) are still limited in horizontal resolution and are too expensive to implement to generate enough events to include rare ones. In this study, we apply a simpler statistical/deterministic hurricane model (Emanuel et al. 2006) to simulate large numbers of synthetic storms under a given (observed or projected) climate condition. The method has been shown to generate realistic extremes in various basins (Emanuel et al. 2008 and 2010). We also apply a hydrodynamic model (ADCIRC; Luettich et al. 1992) to simulate the storm surges generated by these storms. We then search for black swan TCs, in terms of the joint wind and surge damage potential, in the generated large databases. Heavy rainfall is another important TC hazard and will be considered in a future study. We focus on three areas: Tampa Bay in the U.S., the Persian Gulf, and Darwin in Australia. Tampa Bay is highly vulnerable to storm surge as it is surrounded by shallow water and low-lying lands, much of which may be inundated by a storm tide of 6 m. High surges are generated by storms with a broad

  12. The SWAN-SCALE code for the optimization of critical systems

    International Nuclear Information System (INIS)

    Greenspan, E.; Karni, Y.; Regev, D.; Petrie, L.M.

    1999-01-01

    The SWAN optimization code was recently developed to identify the maximum value of k eff for a given mass of fissile material when in combination with other specified materials. The optimization process is iterative; in each iteration SWAN varies the zone-dependent concentration of the system constituents. This change is guided by the equal volume replacement effectiveness functions (EVREF) that SWAN generates using first-order perturbation theory. Previously, SWAN did not have provisions to account for the effect of the composition changes on neutron cross-section resonance self-shielding; it used the cross sections corresponding to the initial system composition. In support of the US Department of Energy Nuclear Criticality Safety Program, the authors recently removed the limitation on resonance self-shielding by coupling SWAN with the SCALE code package. The purpose of this paper is to briefly describe the resulting SWAN-SCALE code and to illustrate the effect that neutron cross-section self-shielding could have on the maximum k eff and on the corresponding system composition

  13. Lead poisoning and other mortality factors in trumpeter swans

    Science.gov (United States)

    Blus, L.J.; Stroud, R.K.; Reiswig, B.; McEneaney, T.

    1989-01-01

    Lead poisoning and other causes of mortality of trumpeter swans were investigated. Necropsies or Pb concentrations in livers were available for 72 trumpeter swans found dead in seven western states from 1976 to 1987; data from other published and unpublished sources also are summarized. Ingestion of lead artifacts accounted for about 20% of the known mortality of trumpeter swans in the tri-state area of Idaho, Montana and Wyoming, where the population has been declining for several decades.

  14. Statistical characteristics of breakthrough discoveries in science using the metaphor of black and white swans

    Science.gov (United States)

    Zeng, Carl J.; Qi, Eric P.; Li, Simon S.; Stanley, H. Eugene; Ye, Fred Y.

    2017-12-01

    A publication that reports a breakthrough discovery in a particular scientific field is referred to as a ;black swan;, and the most highly-cited papers previously published in the same field ;white swans;. Important scientific progress occurs when ;white swans; meet a ;black swan;, and the citation patterns of the ;white swans; change. This metaphor combines scientific discoveries and scientometric data and suggests that breakthrough scientific discoveries are either ;black swans; or ;grey-black swans;.

  15. Artificial intelligence based decision support for trumpeter swan management

    Science.gov (United States)

    Sojda, Richard S.

    2002-01-01

    The number of trumpeter swans (Cygnus buccinator) breeding in the Tri-State area where Montana, Idaho, and Wyoming come together has declined to just a few hundred pairs. However, these birds are part of the Rocky Mountain Population which additionally has over 3,500 birds breeding in Alberta, British Columbia, Northwest Territories, and Yukon Territory. To a large degree, these birds seem to have abandoned traditional migratory pathways in the flyway. Waterfowl managers have been interested in decision support tools that would help them explore simulated management scenarios in their quest towards reaching population recovery and the reestablishment of traditional migratory pathways. I have developed a decision support system to assist biologists with such management, especially related to wetland ecology. Decision support systems use a combination of models, analytical techniques, and information retrieval to help develop and evaluate appropriate alternatives. Swan management is a domain that is ecologically complex, and this complexity is compounded by spatial and temporal issues. As such, swan management is an inherently distributed problem. Therefore, the ecological context for modeling swan movements in response to management actions was built as a multiagent system of interacting intelligent agents that implements a queuing model representing swan migration. These agents accessed ecological knowledge about swans, their habitats, and flyway management principles from three independent expert systems. The agents were autonomous, had some sensory capability, and could respond to changing conditions. A key problem when developing ecological decision support systems is empirically determining that the recommendations provided are valid. Because Rocky Mountain trumpeter swans have been surveyed for a long period of time, I was able to compare simulated distributions provided by the system with actual field observations across 20 areas for the period 1988

  16. Free Will, Black Swans and Addiction.

    Science.gov (United States)

    Fenton, Ted; Wiers, Reinout W

    2017-01-01

    The current dominant perspective on addiction as a brain disease has been challenged recently by Marc Lewis, who argued that the brain-changes related to addiction are similar to everyday changes of the brain. From this alternative perspective, addictions are bad habits that can be broken, provided that people are motivated to change. In that case, autonomous choice or "free will" can overcome bad influences from genes and or environments and brain-changes related to addiction. Even though we concur with Lewis that there are issues with the brain disease perspective, we also argue that pointing to black swans can be important, that is: there can be severe cases where addiction indeed tips over into the category of brain disease, but obviously that does not prove that every case of addiction falls into the disease category, that all swans are black. We argue that, for example, people suffering from Korsakoff's syndrome, can be described as having a brain disease, often caused by alcohol addiction. Moreover, the brain changes occurring with addiction are related to choice-behaviour (and the related notions of willed action), habit formation and insight, hence essential mental abilities to break the addiction. We argue for a more graded perspective, where both black swans (severe brain disease which makes recovery virtually impossible) and white swans (unaffected brain) are rare, and most cases of addiction come as geese in different shades of gray.

  17. The SWAN/NPSOL code system for multivariable multiconstraint shield optimization

    International Nuclear Information System (INIS)

    Watkins, E.F.; Greenspan, E.

    1995-01-01

    SWAN is a useful code for optimization of source-driven systems, i.e., systems for which the neutron and photon distribution is the solution of the inhomogeneous transport equation. Over the years, SWAN has been applied to the optimization of a variety of nuclear systems, such as minimizing the thickness of fusion reactor blankets and shields, the weight of space reactor shields, the cost for an ICF target chamber shield, and the background radiation for explosive detection systems and maximizing the beam quality for boron neutron capture therapy applications. However, SWAN's optimization module can handle up to a single constraint and was inefficient in handling problems with many variables. The purpose of this work is to upgrade SWAN's optimization capability

  18. Poročilo o obročkanju ptic v Sloveniji v letu 2016 in pojavljanje mušje listnice Phylloscopus inornatus v 25 letih v Sloveniji

    Directory of Open Access Journals (Sweden)

    Vrezec Al

    2017-12-01

    Full Text Available In 2016, data on 176 bird species were gathered during bird ringing activities in Slovenia. A total of 65,711 birds of 165 different species were ringed. Furthermore, 148 recoveries of birds ringed in Slovenia and found abroad, 245 foreign recoveries in Slovenia and 1840 local recoveries were made. The most frequently ringed species was the Blackcap Sylvia atricapilla. Among the ringed nestlings, Great Tits Parus major, Tree Sparrows Passer montanus and White Storks Ciconia ciconia predominated. Considering recoveries of birds ringed or found abroad, the most frequent were finds based on colour rings, especially of Black-headed Gulls Chroicocephalus ridibundus, Mute Swans Cygnus olor and Common Terns Sterna hirundo. As far as local recoveries are concerned, most data were collected for Great Tit and Siskin Spinus spinus. Among rare species, two Yellow-browed Warblers Phylloscopus inornatus were ringed, one Paddyfield Warbler Acrocephalus agricola, one Little Emberiza pusilla and one Black-headed Bunting Emberiza melanocephala, the latter as a singing male, which probably also bred in 2016. The catch frequency of the Yellow-browed Warblers has indeed been increasing in Slovenia in the last 25 years, but this is still a rare and irregular vagrant on autumn migration.

  19. SWAN: a Service for Interactive Analysis in the Cloud

    CERN Document Server

    Piparo, Danilo; Mato, Pere; Mascetti, Luca; Moscicki, Jakub; Lamanna, Massimo

    2016-01-01

    SWAN (Service for Web based ANalysis) is a platform to perform interactive data analysis in the cloud. SWAN allows users to write and run their data analyses with only a web browser, leveraging on the widely-adopted Jupyter notebook interface. The user code, executions and data live entirely in the cloud. SWAN makes it easier to produce and share results and scientific code, access scientific software, produce tutorials and demonstrations as well as preserve analyses. Furthermore, it is also a powerful tool for non-scientific data analytics. This paper describes how a pilot of the SWAN service was implemented and deployed at CERN. Its backend combines state-of-the-art software technologies with a set of existing IT services such as user authentication, virtual computing infrastructure, mass storage, file synchronisation and sharing, specialised clusters and batch systems. The added value of this combination of services is discussed, with special focus on the opportunities offered by the CERNBox service and it...

  20. Lead poisoning in whooper and tundra swans.

    Science.gov (United States)

    Nakade, Tetsuya; Tomura, Yoshihiro; Jin, Kazuo; Taniyama, Hiroyuki; Yamamoto, Mutsuki; Kikkawa, Aya; Miyagi, Kunitaro; Uchida, Eiji; Asakawa, Mitsuhiko; Mukai, Takeshi; Shirasawa, Masahiko; Yamaguchi, Mamoru

    2005-01-01

    Six weak whooper swans (Cygnus cygnus) and two weak tundra swans (Cygnus columbianus) were found at Swamp Miyajima (Hokkaido, Japan) in May 1998. Anorexia, depression, green watery feces, pale conjunctiva, and anemia were observed. Radiographs showed from six to 38 suspected lead pellets in the gizzard. Blood lead concentrations were 2.5-6.7 microg/g (mean+/-SD=4.6+/-1.14 microg/g) on day 1. After blood collection, the birds were treated with calcium disodium ethylenediaminetetraacetate (CaEDTA) given intravenously and force fed. Despite treatment, seven birds died the next day. Green, bile-stained livers and pale or green kidneys were observed on necropsy. Microscopically, bile pigment was widespread in the liver and acid-fast intranuclear inclusion bodies were observed in renal tubular epithelium. Lead concentrations in livers and kidneys were 14.0-30.4 microg/g and 30.2-122 microg/g wet weight, respectively. Only one bird survived and this whooper swan continued to be treated with CaEDTA and activated charcoal. No lead shot was observed in the proventriculus and gizzard by radiography on day 64 and the blood lead concentration decreased from 2.9 microg/g to 0.09 microg/g during that same period. After 4 mo of rehabilitation, the whooper swan was returned to the wild. Lead intoxication continues to be a problem at Swamp Miyajima.

  1. Popular Music in Southeast Asia : Banal Beats, Muted Histories

    NARCIS (Netherlands)

    Barendregt, Bart; Keppy, Peter; Schulte Nordholt, Henk

    2017-01-01

    'Popular Music in Southeast Asia: Banal Beats, Muted Histories' offers a cultural history of modern Southeast Asia from the original vantage point of popular music since the 1920s up to the present. By creatively connecting indigenous musical styles with foreign musical genres, Southeast Asians

  2. Implications of black swans to the foundations and practice of risk assessment and management

    International Nuclear Information System (INIS)

    Aven, Terje

    2015-01-01

    In this article, we discuss how to deal with black swans in a risk context. A black swan is here understood as a surprising extreme event relative to one's knowledge/beliefs, and can be of different types: a) unknown unknowns, b) unknown knowns (we do not have the knowledge but others do) and c) events that are judged to have a negligible probability of occurrence and thus are not believed to occur. In the article, we review the current approaches for confronting black swans, the aim being to gain new insights by addressing the three types of black swans separately, motivated by the fact that they require different types of measures. The main conclusions of the article are that there is a need to i) extend the current risk conceptualisation and treatment frameworks to include the black swan risk, ii) develop a new generation of risk assessment and decision support methods that place more emphasis on the black swan risk and iii) better understand what analysis captures and what lies within the management domain. - Highlights: • The article provides further clarifications on the meaning of black swans. • It reviews and discusses current approaches for confronting black swans. • It provides new insights by addressing three types of black swans separately. • It points to the need for improvements on concepts, assessment and management

  3. The black swan the impact of the highly improbable

    CERN Document Server

    Taleb, Nassim Nicholas

    2010-01-01

    A black swan is a highly improbable event with three principal characteristics: It is unpredictable; it carries a massive impact; and, after the fact, we concoct an explanation that makes it appear less random, and more predictable, than it was. The astonishing success of Google was a black swan; so was 9/11. For Nassim Nicholas Taleb, black swans underlie almost everything about our world, from the rise of religions to events in our own personal lives. Why do we not acknowledge the phenomenon of black swans until after they occur? Part of the answer, according to Taleb, is that humans are hardwired to learn specifics when they should be focused on generalities. We concentrate on things we already know and time and time again fail to take into consideration what we don’t know. We are, therefore, unable to truly estimate opportunities, too vulnerable to the impulse to simplify, narrate, and categorize, and not open enough to rewarding those who can imagine the “impossible.” For years, Taleb has studi...

  4. Inaudible functional MRI using a truly mute gradient echo sequence

    International Nuclear Information System (INIS)

    Marcar, V.L.; Girard, F.; Rinkel, Y.; Schneider, J.F.; Martin, E.

    2002-01-01

    We performed functional MRI experiments using a mute version of a gradient echo sequence on adult volunteers using either a simple visual stimulus (flicker goggles: 4 subjects) or an auditory stimulus (music: 4 subjects). Because the mute sequence delivers fewer images per unit time than a fast echo planar imaging (EPI) sequence, we explored our data using a parametric ANOVA test and a non-parametric Wilcoxon-Mann-Whitney test in addition to performing a cross-correlation analysis. All three methods were in close agreement regarding the location of the BOLD contrast signal change. We demonstrated that, using appropriate statistical analysis, functional MRI using an MR sequence that is acoustically inaudible to the subject is feasible. Furthermore compared with the ''silent'' event-related procedures involving an EPI protocol, our mGE protocol compares favourably with respect to experiment time and the BOLD signal. (orig.)

  5. Black swans and dragon kings: A unified model

    Science.gov (United States)

    Eliazar, Iddo

    2017-09-01

    The term “black swan” is a metaphor for outlier events whose statistics are characterized by Pareto's Law and by Zipf's Law; namely, statistics governed by power-law tails. The term “dragon king” is a metaphor for a singular outlier event which, in comparison with all other outlier events, is in a league of its own. As an illustrative example consider the wealth of a family that is sampled at random from a medieval society: the nobility constitutes the black-swan category, and the royal family constitutes the dragon-king category. In this paper we present and analyze a dynamical model that generates, universally and jointly, black swans and dragon kings. According to this model, growing from the microscopic scale to the macroscopic scale, black swans and dragon kings emerge together and invariantly with respect to initial conditions.

  6. Satellite tracking of the migration of Whooper Swans Cygnus cygnus wintering in Japan

    Science.gov (United States)

    Shimada, Tetsuo; Yamaguchi, Noriyuki M.; Hijikata, N.; Hiraoka, Emiko N.; Hupp, Jerry; Flint, Paul L.; Tokita, Ken-ichi; Fujita, Go; Uchida, Kiyoshi; Sato, F.; Kurechi, Masayuki; Pearce, John M.; Ramey, Andy M.; Higuchi, Hiroyoshi

    2014-01-01

    We satellite-tracked Whooper Swans Cygnus cygnus wintering in northern Japan to document their migration routes and timing, and to identify breeding areas. From 47 swans that we marked at Lake Izunuma-Uchinuma, Miyagi Prefecture, northeast Honshu, and at Lake Kussharo, east Hokkaido, we observed 57 spring and 33 autumn migrations from 2009-2012. In spring, swans migrated north along Sakhalin Island from eastern Hokkaido using stopovers in Sakhalin, at the mouth of the Amur River and in northern coastal areas of the Sea of Okhotsk. They ultimately reached molting/breedmg areas along the Indigirka River and the lower Kolyma River in northern Russia. In autumn, the swans basically reversed the spring migration routes. We identified northern Honshu, eastern Hokkaido, coastal areas in Sakhalin, the lower Amur River and northern coastal areas of the Sea of Okhotsk as the most frequent stopover sites, and the middle reaches of the Indigirka and the lower Kolyma River as presumed breeding sites. Our results are helpful in understanding the distribution of the breeding and stopover sites of Whooper Swans wintering in Japan and in identifying their major migration habitats. Our findings contribute to understanding the potential transmission process of avian influenza viruses potentially carried by swans, and provide information necessary to conserve Whooper Swans in East Asia.

  7. Inaudible functional MRI using a truly mute gradient echo sequence

    Energy Technology Data Exchange (ETDEWEB)

    Marcar, V.L. [University of Zurich, Department of Psychology, Neuropsychology, Treichlerstrasse 10, 8032 Zurich (Switzerland); Girard, F. [GE Medical Systems SA, 283, rue de la Miniere B.P. 34, 78533 Buc Cedex (France); Rinkel, Y.; Schneider, J.F.; Martin, E. [University Children' s Hospital, Neuroradiology and Magnetic Resonance, Department of Diagnostic Imaging, Steinwiesstrasse 75, 8032 Zurich (Switzerland)

    2002-11-01

    We performed functional MRI experiments using a mute version of a gradient echo sequence on adult volunteers using either a simple visual stimulus (flicker goggles: 4 subjects) or an auditory stimulus (music: 4 subjects). Because the mute sequence delivers fewer images per unit time than a fast echo planar imaging (EPI) sequence, we explored our data using a parametric ANOVA test and a non-parametric Wilcoxon-Mann-Whitney test in addition to performing a cross-correlation analysis. All three methods were in close agreement regarding the location of the BOLD contrast signal change. We demonstrated that, using appropriate statistical analysis, functional MRI using an MR sequence that is acoustically inaudible to the subject is feasible. Furthermore compared with the ''silent'' event-related procedures involving an EPI protocol, our mGE protocol compares favourably with respect to experiment time and the BOLD signal. (orig.)

  8. Lead toxicosis in tundra swans near a mining and smelting complex in northern Idaho

    Science.gov (United States)

    Blus, L.J.; Henny, C.J.; Hoffman, D.J.; Grove, R.A.

    1991-01-01

    Die-offs of waterfowl have occurred in the Coeur d`Alene River system in northern Idaho since at least the early 1900`s. We investigated causes of mortality and lead and cadmium contamination of 46 tundra swans (Cygnus columbianus) from 1987 to 1989; an additional 22 swans found dead in 1990 were not examined. We necropsied 43 of the 46 birds found from 1987 to 1989; 38 of these were from the Coeur d`Alene River system, which has been contaminated with mining and smelting wastes for a century, and the other 5 were from a nearby, relatively uncontaminated area. Of the 36 livers of swans from the contaminated area that were analyzed, 32 contained lethal levels of lead (6 to 40 micrograms/g, wet weight) and all birds exhibited several symptoms of lead poisoning, notably enlarged gall bladders containing viscous, darkgreen bile. Only 13% of the lead-poisoned birds (10% when data were included from other studies of swans in the area) contained shot, compared to 95% of lead-poisoning swans in studies outside northern Idaho. Lead concentrations in blood samples from 16 apparently healthy swans (0.5 to 2.3 micrograms/g, and 4 leadpoisoned birds found moribund (1.3 to 9.6 micrograms/g) indicating that tundra swans accumulated high levels of lead from ingestion of sediment that contained up to 8,700 micrograms/g of lead and plants that contained up to 400 micrograms/g. The swans spend only a few weeks in the area staging during the spring migration. The five tundra swans from the uncontaminated area had low levels of lead and essentially no symptoms of lead poisoning.(ABSTRACT TRUNCATED AT 250 WORDS)

  9. Conferences are like swans

    OpenAIRE

    Corker, Chris

    2012-01-01

    Chris Corker was the lead on bringing the 2011 Higher Education Research Scholarship Group Conference to fruition, both in the months preceding the event and on the day. In this viewpoint, Chris shares his experiences of conference administration and delivery, and explores how conferences and swans have more in common that you would imagine.

  10. Accidents, 'black swans' and risks

    International Nuclear Information System (INIS)

    Luxat, J.C.

    2013-01-01

    Major accidents and natural disasters with severe consequences have occurred in all sectors of industrial activity with relatively high frequency. The severe consequences of concern involve either significant loss of life or major economic loss, or both loss of life and economic loss. Such events have the last two years been referred to as 'black swan' events following publication of Taleb's bestselling book. These events demonstrate limits to PRA application that arise from the underlying high uncertainty associated with the estimation of frequency of occurrence of such events. An approach is proposed in this paper that, consistent with the concept of defense in depth employed by the nuclear industry, augments probabilistic risk assessment with a methodology based upon 'threat - risk assessment'. This approach shifts these very low frequency high consequence 'black swan' events out of the probabilistic risk assessment domain into a deterministic emergency response assessment domain. (author)

  11. Delineation of Tundra Swan Cygnus c. columbianus populations in North America: geographic boundaries and interchange

    Science.gov (United States)

    Ely, Craig R.; Sladen, William J. L.; Wilson, Heather M.; Savage, Susan E.; Sowl, Kristine M.; Henry, Bill; Schwitters, Mike; Snowden, James

    2014-01-01

    North American Tundra Swans Cygnus c. columbianus are composed of two wellrecognised populations: an Eastern Population (EP) that breeds across northern Canada and north of the Brooks Range in Alaska, which migrates to the eastern seaboard of the United States, and a Western Population (WP) that breeds in coastal regions of Alaska south of the Brooks Range and migrates to western North America. We present results of a recent major ringing effort from across the breeding range in Alaska to provide a better definition of the geographic extent of the migratory divide in Alaska. We also reassess the staging and winter distributions of these populations based on locations of birds tracked using satellite transmitters, and recent recoveries and sightings of neck-collared birds. Summer sympatry of EP and WP Tundra Swans is very limited, and largely confined to a small area in northwest Alaska. Autumn migration pathways of EP and WP Tundra swans abut in southwest Saskatchewan, a region where migrating WP birds turn west, and EP birds deviate abruptly eastward. Overall, from 1989 to 2013 inclusive, 2.6% of recoveries or resightings reported to the USGS Bird Banding Laboratory were of birds that moved from the domain of the population in which they were initially captured to within the range of the other population; a proportion roughly comparable to the results of Limpert et al. (1991) for years before 1990. Of the 70 cross-boundary movements reported since 1989, 39% were of birds marked on breeding areas and 61% were of birds marked on wintering areas. Dispersing swans (i.e. those that made crossboundary movements) did not differ with respect to age or sex from those that did not move between populations. The Brooks Range in northern Alaska effectively separates the two populations within Alaska, but climate-induced changes in tundra breeding habitats and losses of wetlands on staging areas may alter the distribution for both of these populations.

  12. Movement of foraging Tundra Swans explained by spatial pattern in cryptic food densities.

    Science.gov (United States)

    Klaassen, Raymond H G; Nolet, Bart A; Bankert, Daniëlle

    2006-09-01

    We tested whether Tundra Swans use information on the spatial distribution of cryptic food items (below ground Sago pondweed tubers) to shape their movement paths. In a continuous environment, swans create their own food patches by digging craters, which they exploit in several feeding bouts. Series of short (1 m). Tuber biomass densities showed a positive spatial auto-correlation at a short distance (25 g/m2) and to a more distant patch (at 7-8 m) if the food density in the current patch had been low (3 m) from a low-density patch and a short distance (<3 m) from a high-density patch. The quantitative agreement between prediction and observation was greater for swans feeding in pairs than for solitary swans. The result of this movement strategy is that swans visit high-density patches at a higher frequency than on offer and, consequently, achieve a 38% higher long-term gain rate. Swans also take advantage of spatial variance in food abundance by regulating the time in patches, staying longer and consuming more food from rich than from poor patches. We can conclude that the shape of the foraging path is a reflection of the spatial pattern in the distribution of tuber densities and can be understood from an optimal foraging perspective.

  13. Detection ratios on winter surveys of Rocky Mountain Trumpeter Swans Cygnus buccinator

    Science.gov (United States)

    Bart, J.; Mitchell, C.D.; Fisher, M.N.; Dubovsky, J.A.

    2007-01-01

    We estimated the detection ratio for Rocky Mountain Trumpeter Swans Cygnus buccinator that were counted during aerial surveys made in winter. The standard survey involved counting white or grey birds on snow and ice and thus might be expected to have had low detection ratios. On the other hand, observers were permitted to circle areas where the birds were concentrated multiple times to obtain accurate counts. Actual numbers present were estimated by conducting additional intensive aerial counts either immediately before or immediately after the standard count. Surveyors continued the intensive surveys at each area until consecutive counts were identical. The surveys were made at 10 locations in 2006 and at 19 locations in 2007. A total of 2,452 swans were counted on the intensive surveys. Detection ratios did not vary detectably with year, observer, which survey was conducted first, age of the swans, or the number of swans present. The overall detection ratio was 0.93 (90% confidence interval 0.82-1.04), indicating that the counts were quite accurate. Results are used to depict changes in population size for Rocky Mountain Trumpeter Swans from 1974-2007. ?? Wildfowl & Wetlands Trust.

  14. Analyzing data files in SWAN

    CERN Document Server

    Gajam, Niharika

    2016-01-01

    Traditionally analyzing data happens via batch-processing and interactive work on the terminal. The project aims to provide another way of analyzing data files: A cloud-based approach. It aims to make it a productive and interactive environment through the combination of FCC and SWAN software.

  15. Centenarians and supercentenarians: a black swan. Emerging social, medical and surgical problems.

    Science.gov (United States)

    Vacante, Marco; D'Agata, Velia; Motta, Massimo; Malaguarnera, Giulia; Biondi, Antonio; Basile, Francesco; Malaguarnera, Michele; Gagliano, Caterina; Drago, Filippo; Salamone, Salvatore

    2012-01-01

    The Black Swan Theory was described by Nassim Nicholas Taleb in his book "The Black Swan". This theory refers to "high-impact, hard-to-predict, and rare events beyond the realm of normal expectations". According to Taleb's criteria, a Black Swan Event is a surprise, it has a major impact and after the fact, the event is rationalized by hindsight, as if it had been expected. For most of human history centenarians were a rare and unpredictable phenomenon. The improvements of the social-environmental conditions, of medical care, and the quality of life caused a general improvement of the health status of the population and a consequent reduction of the overall morbidity and mortality, resulting in an overall increase of life expectancy. The study of centenarians and supercentenarians had the objective to consider this black swan and to evaluate the health, welfare, social and economic consequences of this phenomenon.

  16. Mass production of `Swan`s Golden`, Cupressus sempervirens by tissue culture and its radiation breeding. 2. Study on growth regulating substance to stimulate the elongation of shoot apex

    Energy Technology Data Exchange (ETDEWEB)

    Suda, Hirokatsu [Tokyo Metropolitan Isotope Research Center (Japan)

    1997-09-01

    Some species of `Swan`s Golden` have been propagated by means of grafting because propagation by cutting is difficult. However, not a few species of the plant are easily lodged, resulting that spreading of `Swan`s Golden` is difficult. Here, an investigation was made on growth regulating substances added into the basal medium in respects of their kinds and concentrations and also the kind of medium for successive culture. As the basal medium, SH medium supplemented with 4 g/l of gel-light and 3 g/l of carbon-powder was used. The optimum medium for the initiation of culture was the basal medium added with zeatin (Ze) and gibberellin (GA) and it was also suitable for successive culture after the 14 day. The medium added with Ze and benzyladenine (BA) or Ze alone was found to be most suitable for the culture after the 28 day. The concentration was optimum at 1 - 2.5 mg/l for either of these growth regulating substances. (M.N.)

  17. Chewing lice of swan geese (Anser cygnoides): New host-parasite associations

    Science.gov (United States)

    Choi, Chang-Yong; Takekawa, John Y.; Prosser, Diann J.; Smith, Lacy M.; Ely, Craig R.; Fox, Anthony D.; Cao, Lei; Wang, Xin; Batbayar, Nyambayar; Natsagdorj, Tseveenmayadag; Xiao, Xiangming

    2016-01-01

    Chewing lice (Phthiraptera) that parasitize the globally threatened swan goose Anser cygnoides have been long recognized since the early 19th century, but those records were probably biased towards sampling of captive or domestic geese due to the small population size and limited distribution of its wild hosts. To better understand the lice species parasitizing swan geese that are endemic to East Asia, we collected chewing lice from 14 wild geese caught at 3 lakes in northeastern Mongolia. The lice were morphologically identified as 16 Trinoton anserinum (Fabricius, 1805), 11 Ornithobius domesticus Arnold, 2005, and 1 Anaticola anseris (Linnaeus, 1758). These species are known from other geese and swans, but all of them were new to the swan goose. This result also indicates no overlap in lice species between older records and our findings from wild birds. Thus, ectoparasites collected from domestic or captive animals may provide biased information on the occurrence, prevalence, host selection, and host-ectoparasite interactions from those on wild hosts.

  18. Sibling Group Play Therapy: An Effective Alternative with an Elective Mute Child.

    Science.gov (United States)

    Barlow, Karen; And Others

    1986-01-01

    Presents the case study of an elective mute child. Describes the effects of sibling play therapy and lists implications for school counselors who might use group or sibling play therapy in their developmental guidance programs. (ABB)

  19. A hybrid version of swan for fast and efficient practical wave modelling

    NARCIS (Netherlands)

    M. Genseberger (Menno); J. Donners

    2016-01-01

    htmlabstractIn the Netherlands, for coastal and inland water applications, wave modelling with SWAN has become a main ingredient. However, computational times are relatively high. Therefore we investigated the parallel efficiency of the current MPI and OpenMP versions of SWAN. The MPI version is

  20. Muon Telescope (MuTe): A first study using Geant4

    Science.gov (United States)

    Asorey, H.; Balaguera-Rojas, A.; Calderon-Ardila, R.; Núñez, L. A.; Sanabria-Gómez, J. D.; Súarez-Durán, M.; Tapia, A.

    2017-07-01

    Muon tomography is based on recording the difference of absorption of muons by matter, as ordinary radiography does for using X-rays. The interaction of cosmic rays with the atmosphere produces extensive air showers which provides an abundant source for atmospheric muons, benefiting various applications of muon tomography, particularly the study of the inner structure of volcanoes. The MuTe (for Muon Telescope) is a hybrid detector composed of scintillation bars and a water Cherenkov detector designed to measure cosmic muon flux crossing volcanic edifices. This detector consists of two scintillator plates (1.44 m2 with 30 x 30 pixels), with a maximum distance of 2.0m of separation. In this work we report the first simulation of the MuTe using GEANT4 -set of simulation tools, based in C++ - that provides information about the interaction between radiation and matter. This computational tool allows us to know the energy deposited by the muons and modeling the response of the scintillators and the water cherenkov detector to the passage of radiation which is crucial to compare to our data analysis.

  1. Blood lead concentrations in Alaskan tundra swans: linking breeding and wintering areas with satellite telemetry.

    Science.gov (United States)

    Ely, Craig R; Franson, J Christian

    2014-04-01

    Tundra swans (Cygnus columbianus) like many waterfowl species are susceptible to lead (Pb) poisoning, and Pb-induced mortality has been reported from many areas of their wintering range. Little is known however about Pb levels throughout the annual cycle of tundra swans, especially during summer when birds are on remote northern breeding areas where they are less likely to be exposed to anthropogenic sources of Pb. Our objective was to document summer Pb levels in tundra swans throughout their breeding range in Alaska to determine if there were population-specific differences in blood Pb concentrations that might pose a threat to swans and to humans that may consume them. We measured blood Pb concentrations in tundra swans at five locations in Alaska, representing birds that winter in both the Pacific Flyway and Atlantic Flyway. We also marked swans at each location with satellite transmitters and coded neck bands, to identify staging and wintering sites and determine if winter site use correlated with summer Pb concentrations. Blood Pb levels were generally low (<0.2 μg/ml) in swans across all breeding areas. Pb levels were lower in cygnets than adults, suggesting that swans were likely exposed to Pb on wintering areas or on return migration to Alaska, rather than on the summer breeding grounds. Blood Pb levels varied significantly across the five breeding areas, with highest concentrations in birds on the North Slope of Alaska (wintering in the Atlantic Flyway), and lowest in birds from the lower Alaska Peninsula that rarely migrate south for winter.

  2. Age-specific survival of tundra swans on the lower Alaska Peninsula

    Science.gov (United States)

    Meixell, Brandt W.; Lindberg, Mark S.; Conn, Paul B.; Dau, Christian P.; Sarvis, John E.; Sowl, Kristine M.

    2013-01-01

    The population of Tundra Swans (Cygnus columbianus columbianus) breeding on the lower Alaska Peninsula represents the southern extremity of the species' range and is uniquely nonmigratory. We used data on recaptures, resightings, and recoveries of neck-collared Tundra Swans on the lower Alaska Peninsula to estimate collar loss, annual apparent survival, and other demographic parameters for the years 1978–1989. Annual collar loss was greater for adult males fitted with either the thinner collar type (0.34) or the thicker collar type (0.15) than for other age/sex classes (thinner: 0.10, thicker: 0.04). The apparent mean probability of survival of adults (0.61) was higher than that of immatures (0.41) and for both age classes varied considerably by year (adult range: 0.44–0.95, immature range: 0.25–0.90). To assess effects of permanent emigration by age and breeding class, we analyzed post hoc the encounter histories of swans known to breed in our study area. The apparent mean survival of known breeders (0.65) was generally higher than that of the entire marked sample but still varied considerably by year (range 0.26–1.00) and indicated that permanent emigration of breeding swans was likely. We suggest that reductions in apparent survival probability were influenced primarily by high and variable rates of permanent emigration and that immigration by swans from elsewhere may be important in sustaining a breeding population at and near Izembek National Wildlife Refuge.

  3. Folding paper swans, modeling lives: the ritual of Filipina eldercare in Israel.

    Science.gov (United States)

    Mazuz, Keren

    2013-06-01

    This article examines the practices of folding paper swans by Filipina migrants employed as live-in caregivers for elderly, dying patients in Israel. These practices create a microsystem model of adjustment through precise, small-scale, and repetitive movements. This microsystem synchronizes a tripartite process: the swan's process of construction, the patient's process of decay, and the caregiver's process of self-creation. In the short term, the microsystem is sustained, but in the long term, the microsystem contains within it the seeds of its own self-destruction, as the patient eventually dies, the caregiver is reassigned to another patient or deported, and the swans are gifted. Therefore, the swan folding expands both medical anthropology understanding of caregiving as a ritual and the phenomenology of global caregivers who use immediately accessible materials-paper and glue-as an imaginative tool for ordering their daily experiences as dislocated and marginalized workers. © 2013 by the American Anthropological Association.

  4. Effect of malnutrition on iron homeostasis in black-necked swans (Cygnus melanocoryphus).

    Science.gov (United States)

    Norambuena, M Cecilia; Bozinovic, Francisco

    2009-12-01

    The Cayumapu River black-necked swan (Cygnus melanocoryphus) population in southern Chile suffered a syndrome of malnutrition and hyperferremia in 2005. The iron metabolic imbalance could not be explained on the basis of the quality of their diet. Hence, the primary objective of this study was to determine the relationship between malnutrition and iron homeostasis in black-necked swans. It was proposed that catabolic processes could increase serum iron levels due to the release of endogenous iron from tissues. A free-living swan population undergoing natural nutritional imbalance due to molting was studied. In addition, swans captured were subjected to a diet restriction until they became emaciated. The results revealed that neither lipolytic activity nor emaciation affected serum iron concentrations. The increment of total iron binding capacity observed was in agreement with the reduction of endogenous iron stored, with the increase of erythropoeitic demand, or with both. Future studies are needed to determine the effect of incremental erythropoietic activity on iron homeostasis in anemic, malnourished birds.

  5. Development and Validation of a Multidisciplinary Tool for Accurate and Efficient Rotorcraft Noise Prediction (MUTE)

    Science.gov (United States)

    Liu, Yi; Anusonti-Inthra, Phuriwat; Diskin, Boris

    2011-01-01

    A physics-based, systematically coupled, multidisciplinary prediction tool (MUTE) for rotorcraft noise was developed and validated with a wide range of flight configurations and conditions. MUTE is an aggregation of multidisciplinary computational tools that accurately and efficiently model the physics of the source of rotorcraft noise, and predict the noise at far-field observer locations. It uses systematic coupling approaches among multiple disciplines including Computational Fluid Dynamics (CFD), Computational Structural Dynamics (CSD), and high fidelity acoustics. Within MUTE, advanced high-order CFD tools are used around the rotor blade to predict the transonic flow (shock wave) effects, which generate the high-speed impulsive noise. Predictions of the blade-vortex interaction noise in low speed flight are also improved by using the Particle Vortex Transport Method (PVTM), which preserves the wake flow details required for blade/wake and fuselage/wake interactions. The accuracy of the source noise prediction is further improved by utilizing a coupling approach between CFD and CSD, so that the effects of key structural dynamics, elastic blade deformations, and trim solutions are correctly represented in the analysis. The blade loading information and/or the flow field parameters around the rotor blade predicted by the CFD/CSD coupling approach are used to predict the acoustic signatures at far-field observer locations with a high-fidelity noise propagation code (WOPWOP3). The predicted results from the MUTE tool for rotor blade aerodynamic loading and far-field acoustic signatures are compared and validated with a variation of experimental data sets, such as UH60-A data, DNW test data and HART II test data.

  6. The Black Swan and the owl of Minerva: Nassim Nicholas Taleb and the historians

    OpenAIRE

    Bennett, Bruce S.

    2014-01-01

    In The Black Swan, Nassim Nicholas Taleb considers the importance in human affairs of "Black Swan" events of low probability but high impact. In the process he argues, in a confrontational manner, that historians' causal narratives are mainly invalid on a number of grounds but especially because the unpredictability of Black Swan (or other) events implies that subsequent narratives connecting events are merely "good-sounding stories". This article analyses Taleb's arguments against historical...

  7. Movement of foraging Tundra Swans explained by spatial pattern in cryptic food densities

    NARCIS (Netherlands)

    Klaassen, R.H.G.; Nolet, B.A.; Bankert, D.

    2006-01-01

    We tested whether Tundra Swans use information on the spatial distribution of cryptic food items (belowground Sago pondweed tubers) to shape their movement paths. In a continuous environment, swans create their own food patches by digging craters, which they exploit in several feeding bouts. Series

  8. Impact of correcting visual impairment and low vision in deaf-mute students in Pune, India.

    Science.gov (United States)

    Gogate, Parikshit; Bhusan, Shashi; Ray, Shantanu; Shinde, Amit

    2016-12-01

    The aim of this study was to evaluate visual acuity and vision function before and after providing spectacles and low vision devices (LVDs) in deaf-mute students. Schools for deaf-mute in West Maharashtra. Hearing-impaired children in all special schools in Pune district underwent detailed visual acuity testing (with teachers' help), refraction, external ocular examination, and fundoscopy. Students with refractive errors and low vision were provided with spectacles and LVD. The LV Prasad-Functional Vision Questionnaire consisting of twenty items was administered to each subject before and after providing spectacles, LVDs. Wilcoxon matched-pairs signed-ranks test. 252/929 (27.1%) students had a refractive error. 794 (85.5%) were profound deaf. Two-hundred and fifty students were dispensed spectacles and LVDs. Mean LogMAR visual acuity before introduction of spectacles and LVDs were 0.33 ± 0.36 which improved to 0.058 (P vision pre- and post-intervention was statistically significant (P vision was much worse than their friend's vision, which was reduced to 17.6% after dispensing spectacles and LVDs. Spectacle and LVD reduced visual impairment and improved vision function in deaf-mute students, augmenting their ability to negotiate in and out of school.

  9. How do "mute" cicadas produce their calling songs?

    Directory of Open Access Journals (Sweden)

    Changqing Luo

    Full Text Available Insects have evolved a variety of structures and mechanisms to produce sounds, which are used for communication both within and between species. Among acoustic insects, cicada males are particularly known for their loud and diverse sounds which function importantly in communication. The main method of sound production in cicadas is the tymbal mechanism, and a relative small number of cicada species possess both tymbal and stridulatory organs. However, cicadas of the genus Karenia do not have any specialized sound-producing structures, so they are referred to as "mute". This denomination is quite misleading, as they indeed produce sounds. Here, we investigate the sound-producing mechanism and acoustic communication of the "mute" cicada, Karenia caelatata, and discover a new sound-production mechanism for cicadas: i.e., K. caelatata produces impact sounds by banging the forewing costa against the operculum. The temporal, frequency and amplitude characteristics of the impact sounds are described. Morphological studies and reflectance-based analyses reveal that the structures involved in sound production of K. caelatata (i.e., forewing, operculum, cruciform elevation, and wing-holding groove on scutellum are all morphologically modified. Acoustic playback experiments and behavioral observations suggest that the impact sounds of K. caelatata are used in intraspecific communication and function as calling songs. The new sound-production mechanism expands our knowledge on the diversity of acoustic signaling behavior in cicadas and further underscores the need for more bioacoustic studies on cicadas which lack tymbal mechanism.

  10. How do "mute" cicadas produce their calling songs?

    Science.gov (United States)

    Luo, Changqing; Wei, Cong; Nansen, Christian

    2015-01-01

    Insects have evolved a variety of structures and mechanisms to produce sounds, which are used for communication both within and between species. Among acoustic insects, cicada males are particularly known for their loud and diverse sounds which function importantly in communication. The main method of sound production in cicadas is the tymbal mechanism, and a relative small number of cicada species possess both tymbal and stridulatory organs. However, cicadas of the genus Karenia do not have any specialized sound-producing structures, so they are referred to as "mute". This denomination is quite misleading, as they indeed produce sounds. Here, we investigate the sound-producing mechanism and acoustic communication of the "mute" cicada, Karenia caelatata, and discover a new sound-production mechanism for cicadas: i.e., K. caelatata produces impact sounds by banging the forewing costa against the operculum. The temporal, frequency and amplitude characteristics of the impact sounds are described. Morphological studies and reflectance-based analyses reveal that the structures involved in sound production of K. caelatata (i.e., forewing, operculum, cruciform elevation, and wing-holding groove on scutellum) are all morphologically modified. Acoustic playback experiments and behavioral observations suggest that the impact sounds of K. caelatata are used in intraspecific communication and function as calling songs. The new sound-production mechanism expands our knowledge on the diversity of acoustic signaling behavior in cicadas and further underscores the need for more bioacoustic studies on cicadas which lack tymbal mechanism.

  11. Maize stubble as foraging habitat for wintering geese and swans in northern Europe

    DEFF Research Database (Denmark)

    Clausen, Kevin Kuhlmann; Madsen, Jesper; Nolet, Bart, A.

    2018-01-01

    Agricultural crops have become increasingly important foraging habitats to geese and swans in northern Europe, and a recent climate-driven expansion in the area of maize fields has led to a rapid increase in the exploitation of this habitat. However, due to the novelty of maize foraging in this r......Agricultural crops have become increasingly important foraging habitats to geese and swans in northern Europe, and a recent climate-driven expansion in the area of maize fields has led to a rapid increase in the exploitation of this habitat. However, due to the novelty of maize foraging...... in this region, little is known about the abundance and energetic value of this resource to foraging birds. In this study we quantify food availability, intake rates and energetic profitability of the maize stubble habitat, and describe the value of this increasingly cultivated crop to wintering geese and swans...... of geese and swans wintering in northern Europe....

  12. Migration strategies of Swan Geese Anser cygnoides from northeast Mongolia

    Science.gov (United States)

    Batbayar, Nyambayar; Takekawa, John Y.; Newman, Scott H.; Prosser, Diann J.; Natsagdorj, Tseveenmyadag; Xiao, Xiangming

    2011-01-01

    In 2006–2008, 25 Swan Geese Anser cygnoides were marked with solar-powered GPS satellite transmitters in northeast Mongolia to examine the timing and pathways of their migration. Most geese began their autumn migration in August, flying southeast toward a staging area at the Yalu River Estuary on the China-North Korea border. After staging for several weeks, the Swan Geese continued to their wintering grounds at wetlands along the Yangtze River Basin of eastern China in December. Spring migration commenced in late February, and the birds following either a same-route or loop migration to arrive at the breeding grounds in mid April. Swan Geese used a larger number of staging areas for a longer duration when they were north of 42°N latitude; they seemed to avoid staging for extended periods in the highly urbanised areas of eastern China. Further research should examine threats and disturbances to the geese in relation to human population growth and increasing urbanisation.

  13. Susceptibility-weighted angiography (SWAN) of cerebral veins and arteries compared to TOF-MRA

    International Nuclear Information System (INIS)

    Boeckh-Behrens, T.; Lutz, J.; Lummel, N.; Burke, M.; Wesemann, T.; Schöpf, V.; Brückmann, H.; Linn, J.

    2012-01-01

    Problem: High resolution, non-contrast imaging of both cerebral veins and arteries by use of gradient echo T2 star weighted angiography (SWAN) is a new method for susceptibility-weighted imaging with short acquisition times. We assessed the potential of this sequence for the depiction of both cerebral veins and arteries. Methods: 15 healthy volunteers were included in the study. MRI was performed on a 3 T MR scanner using the following sequences: (1) a 3D multi-echo gradient echo T2 star weighted angiography (SWAN), (2) an arterial 3D TOF MR angiography and (3) a venous 2D TOF. With regard to the SWAN sequence, both MinIP and MIP images were reconstructed and systematically compared to MIP reconstructions of the artTOF and the venTOF. To suggest possible clinical implications of our findings, we additionally included two illustrative cases. Results: With regard to the visualization of the cerebral veins, the MinIP reconstructions of the SWAN sequence were considerably superior compared to the venTOF. Concerning the depiction of the main segments of the big cerebral arteries the value of the MIP reconstructions of the SWAN was comparable to that of the artTOF with limitations in the homogenity and in the depiction of smaller arteries. Conclusions: SWAN allows for high-resolution visualization of both cerebral veins and arteries in one sequence without application of contrast agent and with significantly shortened scan time compared to the combined scan time of TOF-MRA and TOF-MRV. By use of either MinIP or MIP reconstructions, the arteries can be distinguished from the veins.

  14. Black Swans and the Effectiveness of Remediating Groundwater Contamination

    Science.gov (United States)

    Siegel, D. I.; Otz, M. H.; Otz, I.

    2013-12-01

    Black swans, outliers, dominate science far more than do predictable outcomes. Predictable success constitutes the Black Swan in groundwater remediation. Even the National Research Council concluded that remediating groundwater to drinking water standards has failed in typically complex hydrogeologic settings where heterogeneities and preferential flow paths deflect flow paths obliquely to hydraulic gradients. Natural systems, be they biological or physical, build upon a combination of large-scale regularity coupled to chaos at smaller scales. We show through a review of over 25 case studies that groundwater remediation efforts are best served by coupling parsimonious site characterization to natural and induced geochemical tracer tests to at least know where contamination advects with groundwater in the subsurface. In the majority of our case studies, actual flow paths diverge tens of degrees from anticipated flow paths because of unrecognized heterogeneities in the horizontal direction of transport, let alone the vertical direction. Consequently, regulatory agencies would better serve both the public and the environment by recognizing that long-term groundwater cleanup probably is futile in most hydrogeologic settings except to relaxed standards similar to brownfielding. A Black Swan

  15. Ruffled feathers: Costume, gender and authorship in the Black Swan controversy

    OpenAIRE

    Warner, Helen

    2012-01-01

    In 2011, the popular and trade press reported a dispute between costume designer Amy Westcott and creators of fashion label Rodarte, Kate and Laura Mulleavy, following the decision that the fashion designers were only to receive a back-end credit for their work on psychological thriller Black Swan (Aronofsky, 2010). This article traces the coverage of the Black Swan controversy in order to demonstrate that press discourses surrounding the costume designer perform a series of cultural function...

  16. Pathogenesis of venous hypertrophy associated with schistosomiasis in whooper swans (Cygnus cygnus) in Japan.

    Science.gov (United States)

    Akagami, Masataka; Nakamura, Kikuyasu; Nishino, Hiroto; Seki, Satoko; Shimizu, Hiromi; Yamamoto, Yu

    2010-03-01

    Thirteen whooper swans (Cygnus cygnus) affected with schistosomiasis were examined pathologically. Venous hypertrophy, characterized by marked nodular proliferation of medial smooth muscle fibers with frequent obliteration of the vascular lumen, was observed in eight of the 13 whooper swans. Venous hypertrophy was located in the medium-sized veins of the mesentery, the serosa, and the muscular layer of the duodenum, jejunum, ileum, and cecum. In addition, vascular lesions were seen in the capsule and parenchymal interstitia of the liver, spleen, kidney, heart, aorta, air sac, and pleura. In mild lesions, segmental proliferation of medial smooth muscles was observed in the venous medium of the mesentery and serosa. Moderate lesions had a proliferation of smooth muscles in the veins with obliteration of venous lumens. In marked lesions, more severe proliferation of veins extended into the intestinal muscular layers and depressed them. Schistosome parasites were found in the venous lumens of each of the eight whooper swans with vascular lesions. Bile pigments and hemosiderin were observed in the livers of whooper swans. In addition, adult nematodes (Sarconema sp.) were localized in the myocardium of four of the eight whooper swans. The venous hypertrophy may be caused by the proliferation of medial smooth muscle fibers induced by schistosomiasis.

  17. Migration of Tundra Swans (Cygnus columbianus) Wintering in Japan Using Satellite Tracking: Identification of the Eastern Palearctic Flyway.

    Science.gov (United States)

    Chen, Wenbo; Doko, Tomoko; Fujita, Go; Hijikata, Naoya; Tokita, Ken-Ichi; Uchida, Kiyoshi; Konishi, Kan; Hiraoka, Emiko; Higuchi, Hiroyoshi

    2016-02-01

    Migration through the Eastern Palearctic (EP) flyway by tundra swans (Cygnus columbianus) has not been thoroughly documented. We satellite-tracked the migration of 16 tundra swans that winter in Japan. The objectives of this study were 1) to show the migration pattern of the EP flyway of tundra swans; 2) to compare this pattern with the migration pattern of whooper swans; and 3) to identify stopover sites that are important for these swans' conservation. Tundra swans were captured at Kutcharo Lake, Hokkaido, in 2009-2012 and satellite-tracked. A new method called the "MATCHED (Migratory Analytical Time Change Easy Detection) method" was developed. Based on median, the spring migration began on 18 April and ended on 27 May. Autumn migration began on 9 September and ended on 2 November. The median duration of the spring and autumn migrations were 48 and 50 days, respectively. The mean duration at one stopover site was 5.5 days and 6.8 days for the spring and autumn migrations, respectively. The number of stopover sites was 3.0 and 2.5 for the spring and autumn migrations, respectively. The mean travel distances for the spring and autumn migrations were 6471 and 6331 km, respectively. Seven migration routes passing Sakhalin, the Amur River, and/or Kamchatka were identified. There were 15, 32, and eight wintering, stopover, and breeding sites, respectively. The migration routes and staging areas of tundra swans partially overlap with those of whooper swans, whose migration patterns have been previously documented. The migration patterns of these two swan species that winter in Japan confirm the importance of the Amur River, Udyl' Lake, Shchastya Bay, Aniva Bay, zaliv Chayvo Lake, zal Piltun Lake, zaliv Baykal Lake, Kolyma River, Buyunda River, Sen-kyuyel' Lake, and northern coastal areas of the Sea of Okhotsk.

  18. Susan swan and the female grotesque Susan swan and the female grotesque

    Directory of Open Access Journals (Sweden)

    Suzana Bornéo Funck

    2008-04-01

    Full Text Available Introduced to readers as “the tallest woman freelance writer in Canada”, Susan Swan belongs to a generation of writers whose experimental, innovative fiction has proved vital in the contemporary project of de/re/constructing narrative practice. Her 1983 novel The Biggest Modern Woman of the World constitutes an excellent example of what critic Linda Hutcheon has termed “historiographic metafiction”—”fiction that is intensely, self-reflexively art, but is also grounded in historical, social, and political realities” (Canadian 13. As a conscious engagement with social and historical contexts, such fiction aims at destabilizing and subverting accepted patterns of belief by reconceptualizing and narrating possible subjectivities. By means of intertextuality, especially parody, it engages in an ideological critique in terms of both sexual and national politics. Introduced to readers as “the tallest woman freelance writer in Canada”, Susan Swan belongs to a generation of writers whose experimental, innovative fiction has proved vital in the contemporary project of de/re/constructing narrative practice. Her 1983 novel The Biggest Modern Woman of the World constitutes an excellent example of what critic Linda Hutcheon has termed “historiographic metafiction”—”fiction that is intensely, self-reflexively art, but is also grounded in historical, social, and political realities” (Canadian 13. As a conscious engagement with social and historical contexts, such fiction aims at destabilizing and subverting accepted patterns of belief by reconceptualizing and narrating possible subjectivities. By means of intertextuality, especially parody, it engages in an ideological critique in terms of both sexual and national politics.

  19. Accidents, 'Black Swans' and risk

    Energy Technology Data Exchange (ETDEWEB)

    Luxat, J.C., E-mail: luxatj@mcmaster.ca [McMaster Univ., Dept. of Engineering Physics, Hamilton, Ontario (Canada)

    2013-07-01

    Major accidents and natural disasters with severe consequences have occurred in all sectors of industrial activity with relatively high frequency. The severe consequences of concern involve either significant loss of life or major economic loss, or both loss of life and economic loss. Such events have in the last two years often been referred to as 'Black Swan' events following publication of a best-selling book. The events demonstrate limits to the application of Probabilistic Risk Assessment (PRA) that arise from the underlying unquantifiable uncertainty associated with the estimation of the frequency of occurrence of such events. An approach is proposed in this paper that, consistent with the concept of defense in depth employed by the nuclear industry, augments probabilistic risk assessment with a methodology based upon 'threat -risk assessment'. This approach shifts these very low frequency, high uncertainty, and high consequence 'Black Swan' events out of the probabilistic risk assessment domain and into a deterministic emergency response assessment domain. (author)

  20. Accidents, 'black swans' and risks

    Energy Technology Data Exchange (ETDEWEB)

    Luxat, J.C. [McMaster Univ., Dept. of Engineering Physics, Hamilton, Ontario (Canada)

    2013-06-15

    Major accidents and natural disasters with severe consequences have occurred in all sectors of industrial activity with relatively high frequency. The severe consequences of concern involve either significant loss of life or major economic loss, or both loss of life and economic loss. Such events have the last two years been referred to as 'black swan' events following publication of Taleb's bestselling book. These events demonstrate limits to PRA application that arise from the underlying high uncertainty associated with the estimation of frequency of occurrence of such events. An approach is proposed in this paper that, consistent with the concept of defense in depth employed by the nuclear industry, augments probabilistic risk assessment with a methodology based upon 'threat - risk assessment'. This approach shifts these very low frequency high consequence 'black swan' events out of the probabilistic risk assessment domain into a deterministic emergency response assessment domain. (author)

  1. Accidents, 'Black Swans' and risk

    International Nuclear Information System (INIS)

    Luxat, J.C.

    2013-01-01

    Major accidents and natural disasters with severe consequences have occurred in all sectors of industrial activity with relatively high frequency. The severe consequences of concern involve either significant loss of life or major economic loss, or both loss of life and economic loss. Such events have in the last two years often been referred to as 'Black Swan' events following publication of a best-selling book. The events demonstrate limits to the application of Probabilistic Risk Assessment (PRA) that arise from the underlying unquantifiable uncertainty associated with the estimation of the frequency of occurrence of such events. An approach is proposed in this paper that, consistent with the concept of defense in depth employed by the nuclear industry, augments probabilistic risk assessment with a methodology based upon 'threat -risk assessment'. This approach shifts these very low frequency, high uncertainty, and high consequence 'Black Swan' events out of the probabilistic risk assessment domain and into a deterministic emergency response assessment domain. (author)

  2. Heartworm of swans and geese

    Science.gov (United States)

    Cole, Rebecca A.

    1999-01-01

    Heartworm in swans and geese is caused by a filarial nematode or a roundworm of the superfamily Filarioidea which is transmitted to the bird by a biting louse. The nematode and the louse both are parasites. Sarconema eurycerca is the only one of several species of microfilaria or the first stage juvenile of the parasite found in the circulating blood of waterfowl that is known to be pathogenic or cause clinical disease.

  3. Universal Lessons Learned by a Gastroenterologist from a Deaf and Mute Patient: The Importance of Nonverbal Communication and Establishing Patient Rapport and Trust

    Science.gov (United States)

    Cappel, Mitchell S.

    2009-01-01

    Deaf and mute patients may require minimal extra attention to establish trust and allay anxieties before minor medical maneuvers such as rectal examination. An "extreme" case is reported of the consequences from failure to accomplish this. A generally cooperative deaf and mute patient struggled and suffered a rectal tear and perforation during…

  4. Betsy Byars'"The Summer of the Swans."

    Science.gov (United States)

    Scales, Pat

    1996-01-01

    Summarizes the plot of "The Summer of the Swans," the 1971 Newbery Medal winner; provides discussion questions; outlines activities in drama, art, and language arts; and provides an annotated bibliography of picture books, fiction, and nonfiction dealing with physical, mental, and emotional disabilities. Includes an interview with Betsy…

  5. Chewing Lice of Swan Geese (Anser cygnoides): New Host-Parasite Associations

    DEFF Research Database (Denmark)

    Choi, Chang-Yong; Takekawa, John Y.; Prosser, Diann J.

    2016-01-01

    Chewing lice (Phthiraptera) that parasitize the globally threatened swan goose Anser cygnoides have been long recognized since the early 19th century, but those records were probably biased towards sampling of captive or domestic geese due to the small population size and limited distribution...... of its wild hosts. To better understand the lice species parasitizing swan geese that are endemic to East Asia, we collected chewing lice from 14 wild geese caught at 3 lakes in northeastern Mongolia. The lice were morphologically identified as 16 Trinoton anserinum (Fabricius, 1805), 11 Ornithobius...

  6. Teaching migration routes to canada geese and trumpeter swans using ultralight aircraft, 1990-2001

    Science.gov (United States)

    Sladen, William J. L.; Lishman, W.A.; Ellis, D.H.; Shire, G.G.; Rininger, D.L.; Rees, Eileen C.; Earnst, Susan L.; Coulson, John C.

    2002-01-01

    This paper summarizes eleven years (1990-2001) of experiments to teach Canada Geese (Branta canadensis) and Trumpeter Swans (Cygnus buccinator) pre-selected migration routes using ultralight aircraft. When Canada Geese were trained to follow an ultralight aircraft for southward autumn migrations of 680 or 1,320 km, 81% (83/103) returned on their own in the next spring to near their place of training. In contrast, none returned of 21 similarly raised geese that were transported south in a closed truck over a route of 680 km. Trumpeter Swans have proven more difficult to train. However, in two experiments in which Trumpeter Swans followed an ultralight for the entire pre-selected route, one of three and two of four returned close to their training area. A stage-by-stage method, in which swans were transported in trucks between stops, flown in the vicinity and penned with a view of the night sky, has shown some promise. So far an established migration route (north and south twice) has been confirmed in only two geese

  7. Multimedia information processing in the SWAN mobile networked computing system

    Science.gov (United States)

    Agrawal, Prathima; Hyden, Eoin; Krzyzanowsji, Paul; Srivastava, Mani B.; Trotter, John

    1996-03-01

    Anytime anywhere wireless access to databases, such as medical and inventory records, can simplify workflow management in a business, and reduce or even eliminate the cost of moving paper documents. Moreover, continual progress in wireless access technology promises to provide per-user bandwidths of the order of a few Mbps, at least in indoor environments. When combined with the emerging high-speed integrated service wired networks, it enables ubiquitous and tetherless access to and processing of multimedia information by mobile users. To leverage on this synergy an indoor wireless network based on room-sized cells and multimedia mobile end-points is being developed at AT&T Bell Laboratories. This research network, called SWAN (Seamless Wireless ATM Networking), allows users carrying multimedia end-points such as PDAs, laptops, and portable multimedia terminals, to seamlessly roam while accessing multimedia data streams from the wired backbone network. A distinguishing feature of the SWAN network is its use of end-to-end ATM connectivity as opposed to the connectionless mobile-IP connectivity used by present day wireless data LANs. This choice allows the wireless resource in a cell to be intelligently allocated amongst various ATM virtual circuits according to their quality of service requirements. But an efficient implementation of ATM in a wireless environment requires a proper mobile network architecture. In particular, the wireless link and medium-access layers need to be cognizant of the ATM traffic, while the ATM layers need to be cognizant of the mobility enabled by the wireless layers. This paper presents an overview of SWAN's network architecture, briefly discusses the issues in making ATM mobile and wireless, and describes initial multimedia applications for SWAN.

  8. Zinc toxicosis in a free-flying trumpeter swan (Cygnus buccinator)

    Science.gov (United States)

    Carpenter, J.W.; Andrews, G.A.; Beyer, W.N.

    2004-01-01

    A trumpeter swan (Cygnus buccinator) was observed near it mill pond in Picher, Oklahoma. USA. It became weakened and emaciated after about 1 mo, was captured with little resistance, and taken into captivity for medical care. Serum chemistry results were consistent with hepatic, renal, and muscular damage. Serum zinc concentration was elevated at 11.2 parts per million (ppm). The swan was treated for suspected heavy-metal poisoning, but died overnight. Gross postmortem findings were emaciation and pectoral muscle atrophy. Histopathologic lesions in the pancreas included mild diffuse disruption of acinar architecture, severe diffuse depletion or absence of zymogen granules, occasional apoptotic bodies ics in acinar epithelial cells, and mild interstitial and capsular fibrosis. Zinc concentration in pancreas was 3,200 ppm wet weight, and was similar to that reported in the pancreases of waterfowl known to be killed by zinc toxicity. Zinc concentrations in liver (154 ppm) and kidneys (145 ppm) also were elevated. Acute tubular necrosis of the collecting tubules of the kidneys was also possibly due to zinc toxicity. To the authors' knowledge, this is the first confirmed case of zinc poisoning in a trumpeter swan associated with mining wastes..

  9. Macro Cell Muting Coordination for Non-Uniform Topologies in LTE-A HetNets

    DEFF Research Database (Denmark)

    Soret, Beatriz; Pedersen, Klaus I.

    2013-01-01

    irregular scenarios is how to operate eICIC, and especially how to coordinate macro-cell muting. Our analysis shows that for eICIC to provide gain in such scenarios, it is recommended to use fully time aligned traditional Almost Blank Subframes (ABS) in the macro-cells with picos, while first tier...

  10. Significance of the White Sea as a Stopover for Bewick's Swans Cygnus columbianus bewickii in Spring

    DEFF Research Database (Denmark)

    Nolet, B. A.; Andreev, V. A.; Clausen, P.

    2001-01-01

    We searched for a major stopover site of Bewick's Swans Cygnus columbianus bewickii in the White Sea following the suggestion that one should exist on the stretch between Estonia and the breeding grounds (1750 km). We discovered 733 Swans in Dvina Bay during a late aerial survey in spring 1993. S...... migration. However, in spring the birds probably need this stopover to be able to carry reserves to the breeding grounds. At present, the preservation of the submerged vegetation in Dvina Bay seems to be crucial to the conservation of this Bewick's Swan population....

  11. User's Manual for the Simulating Waves Nearshore Model (SWAN)

    National Research Council Canada - National Science Library

    Allard, Richard

    2002-01-01

    The Simulating WAves Nearshore (SWAN) model is a numerical wave model used to obtain realistic estimates of wave parameters in coastal areas, lakes, and estuaries from given wind, bottom, and current conditions...

  12. Significance of the White Sea as stopover for Bewick's Swans Cygnus columbianus bewickii in spring

    NARCIS (Netherlands)

    Nolet, B.A.; Andreev, V.A; Clausen, P.; Poot, M.; Wessel, E.G.J.

    2001-01-01

    We searched for a major stopover site of Bewick's Swans Cygnus columbianus bewickii in the White Sea following the suggestion that one should exist on the stretch between Estonia and the breeding grounds (1750 km). We discovered 733 Swans in Dvina Bay during a late aerial survey in spring 1993.

  13. Behaviour of wintering Tundra Swans Cygnus columbianus columbianus at the Eel River delta and Humboldt Bay, California, USA

    Science.gov (United States)

    Black, Jeffrey M.; Gress, Carol; Byers, Jacob W.; Jennings, Emily; Ely, Craig R.

    2010-01-01

    Tundra Swan Cygnus columbianus columbinanus phenology and behaviour at the Eel River delta and southern Humboldt Bay in northern California, USA, is described. Counts made each January from 1963 onwards peaked at 1,502 swans in 1988. Monthly counts recorded during the 2006/07 and 2008/09 winters peaked in February, at 1,033 and 772 swans respectively. Swans roosted on ephemeral ponds at the Humboldt Bay National Wildlife Refuge, on ephemeral ponds within grassland pastures in the vicinity of the Refuge, and perhaps also used the Eel River as a roost. Flights between Refuge roosts and the pastures and ponds occurred in the two hours after sunrise and before dark. In winters 2008/09 and 2009/10, the percentage of cygnets in the flocks was 10.6% and 21.4% respectively, and increased to =31% cygnets each year after most swans had departed from the area in March. Average brood size in 2009/10 was 2.1 cygnets. Daily activities consisted of foraging (44.9% of activities recorded), comfort behaviour (22.1%), locomotion (16.2%) and vigilance (15.5%). Eight neck-collared swans identified in the wintering flock were marked at four locations in different parts of Alaska, up to 1,300 km apart.

  14. Centenarians and supercentenarians: a black swan. Emerging social, medical and surgical problems

    OpenAIRE

    Vacante, Marco; D’Agata, Velia; Motta, Massimo; Malaguarnera, Giulia; Biondi, Antonio; Basile, Francesco; Malaguarnera, Michele; Gagliano, Caterina; Drago, Filippo; Salamone, Salvatore

    2012-01-01

    Abstract The Black Swan Theory was described by Nassim Nicholas Taleb in his book “The Black Swan”. This theory refers to “high-impact, hard-to-predict, and rare events beyond the realm of normal expectations”. According to Taleb’s criteria, a Black Swan Event is a surprise, it has a major impact and after the fact, the event is rationalized by hindsight, as if it had been expected. For most of human history centenarians were a rare and unpredictable phenomenon. The improvements of the social...

  15. An Investigation of Control among Parents of Selectively Mute, Anxious, and Non-Anxious Children

    Science.gov (United States)

    Edison, Shannon C.; Evans, Mary Ann; McHolm, Angela E.; Cunningham, Charles E.; Nowakowski, Matilda E.; Boyle, Michael; Schmidt, Louis A.

    2011-01-01

    The authors examined parent-child interactions among three groups: selectively mute, anxious, and non-anxious children in different contexts. The relation between parental control (granting autonomy and high power remarks), child factors (i.e., age, anxiety, verbal participation), and parent anxiety was investigated. Parental control varied by…

  16. The SWAN Captures Variance at the Negative and Positive Ends of the ADHD Symptom Dimension

    Science.gov (United States)

    Arnett, Anne B.; Pennington, Bruce F.; Friend, Angela; Willcutt, Erik G.; Byrne, Brian; Samuelsson, Stefan; Olson, Richard K.

    2013-01-01

    Objective: The Strengths and Weaknesses of ADHD Symptoms and Normal Behavior (SWAN) Rating Scale differs from previous parent reports of ADHD in that it was designed to also measure variability at the positive end of the symptom spectrum. Method: The psychometric properties of the SWAN were tested and compared with an established measure of ADHD,…

  17. Experimental infection of swans and geese with highly pathogenic avian influenza virus (H5N1) of Asian lineage.

    Science.gov (United States)

    Brown, Justin D; Stallknecht, David E; Swayne, David E

    2008-01-01

    The role of wild birds in the epidemiology of the Asian lineage highly pathogenic avian influenza (HPAI) virus subtype H5N1 epizootic and their contribution to the spread of the responsible viruses in Eurasia and Africa are unclear. To better understand the potential role of swans and geese in the epidemiology of this virus, we infected 4 species of swans and 2 species of geese with an HPAI virus of Asian lineage recovered from a whooper swan in Mongolia in 2005, A/whooper swan/Mongolia/244/2005 (H5N1). The highest mortality rates were observed in swans, and species-related differences in clinical illness and viral shedding were evident. These results suggest that the potential for HPAI (H5N1) viral shedding and the movement of infected birds may be species-dependent and can help explain observed deaths associated with HPAI (H5N1) infection in anseriforms in Eurasia.

  18. Migration of whooper swans and outbreaks of highly pathogenic avian influenza H5N1 virus in eastern Asia.

    Science.gov (United States)

    Newman, Scott H; Iverson, Samuel A; Takekawa, John Y; Gilbert, Martin; Prosser, Diann J; Batbayar, Nyambyar; Natsagdorj, Tseveenmyadag; Douglas, David C

    2009-05-28

    Evaluating the potential involvement of wild avifauna in the emergence of highly pathogenic avian influenza H5N1 (hereafter H5N1) requires detailed analyses of temporal and spatial relationships between wild bird movements and disease emergence. The death of wild swans (Cygnus spp.) has been the first indicator of the presence of H5N1 in various Asian and European countries; however their role in the geographic spread of the disease remains poorly understood. We marked 10 whooper swans (Cygnus cygnus) with GPS transmitters in northeastern Mongolia during autumn 2006 and tracked their migratory movements in relation to H5N1 outbreaks. The prevalence of H5N1 outbreaks among poultry in eastern Asia during 2003-2007 peaked during winter, concurrent with whooper swan movements into regions of high poultry density. However outbreaks involving poultry were detected year round, indicating disease perpetuation independent of migratory waterbird presence. In contrast, H5N1 outbreaks involving whooper swans, as well as other migratory waterbirds that succumbed to the disease in eastern Asia, tended to occur during seasons (late spring and summer) and in habitats (areas of natural vegetation) where their potential for contact with poultry is very low to nonexistent. Given what is known about the susceptibility of swans to H5N1, and on the basis of the chronology and rates of whooper swan migration movements, we conclude that although there is broad spatial overlap between whooper swan distributions and H5N1 outbreak locations in eastern Asia, the likelihood of direct transmission between these groups is extremely low. Thus, our data support the hypothesis that swans are best viewed as sentinel species, and moreover, that in eastern Asia, it is most likely that their infections occurred through contact with asymptomatic migratory hosts (e.g., wild ducks) at or near their breeding grounds.

  19. Molecular detection of hematozoa infections in tundra swans relative to migration patterns and ecological conditions at breeding grounds.

    Directory of Open Access Journals (Sweden)

    Andrew M Ramey

    Full Text Available Tundra swans (Cygnus columbianus are broadly distributed in North America, use a wide variety of habitats, and exhibit diverse migration strategies. We investigated patterns of hematozoa infection in three populations of tundra swans that breed in Alaska using satellite tracking to infer host movement and molecular techniques to assess the prevalence and genetic diversity of parasites. We evaluated whether migratory patterns and environmental conditions at breeding areas explain the prevalence of blood parasites in migratory birds by contrasting the fit of competing models formulated in an occupancy modeling framework and calculating the detection probability of the top model using Akaike Information Criterion (AIC. We described genetic diversity of blood parasites in each population of swans by calculating the number of unique parasite haplotypes observed. Blood parasite infection was significantly different between populations of Alaska tundra swans, with the highest estimated prevalence occurring among birds occupying breeding areas with lower mean daily wind speeds and higher daily summer temperatures. Models including covariates of wind speed and temperature during summer months at breeding grounds better predicted hematozoa prevalence than those that included annual migration distance or duration. Genetic diversity of blood parasites in populations of tundra swans appeared to be relative to hematozoa prevalence. Our results suggest ecological conditions at breeding grounds may explain differences of hematozoa infection among populations of tundra swans that breed in Alaska.

  20. Molecular detection of hematozoa infections in tundra swans relative to migration patterns and ecological conditions at breeding grounds.

    Science.gov (United States)

    Ramey, Andrew M; Ely, Craig R; Schmutz, Joel A; Pearce, John M; Heard, Darryl J

    2012-01-01

    Tundra swans (Cygnus columbianus) are broadly distributed in North America, use a wide variety of habitats, and exhibit diverse migration strategies. We investigated patterns of hematozoa infection in three populations of tundra swans that breed in Alaska using satellite tracking to infer host movement and molecular techniques to assess the prevalence and genetic diversity of parasites. We evaluated whether migratory patterns and environmental conditions at breeding areas explain the prevalence of blood parasites in migratory birds by contrasting the fit of competing models formulated in an occupancy modeling framework and calculating the detection probability of the top model using Akaike Information Criterion (AIC). We described genetic diversity of blood parasites in each population of swans by calculating the number of unique parasite haplotypes observed. Blood parasite infection was significantly different between populations of Alaska tundra swans, with the highest estimated prevalence occurring among birds occupying breeding areas with lower mean daily wind speeds and higher daily summer temperatures. Models including covariates of wind speed and temperature during summer months at breeding grounds better predicted hematozoa prevalence than those that included annual migration distance or duration. Genetic diversity of blood parasites in populations of tundra swans appeared to be relative to hematozoa prevalence. Our results suggest ecological conditions at breeding grounds may explain differences of hematozoa infection among populations of tundra swans that breed in Alaska.

  1. Molecular detection of hematozoa infections in tundra swans relative to migration patterns and ecological conditions at breeding grounds

    Science.gov (United States)

    Ramey, Andrew M.; Ely, Craig R.; Schmutz, Joel A.; Pearce, John M.; Heard, Darryl J.

    2012-01-01

    Tundra swans (Cygnus columbianus) are broadly distributed in North America, use a wide variety of habitats, and exhibit diverse migration strategies. We investigated patterns of hematozoa infection in three populations of tundra swans that breed in Alaska using satellite tracking to infer host movement and molecular techniques to assess the prevalence and genetic diversity of parasites. We evaluated whether migratory patterns and environmental conditions at breeding areas explain the prevalence of blood parasites in migratory birds by contrasting the fit of competing models formulated in an occupancy modeling framework and calculating the detection probability of the top model using Akaike Information Criterion (AIC). We described genetic diversity of blood parasites in each population of swans by calculating the number of unique parasite haplotypes observed. Blood parasite infection was significantly different between populations of Alaska tundra swans, with the highest estimated prevalence occurring among birds occupying breeding areas with lower mean daily wind speeds and higher daily summer temperatures. Models including covariates of wind speed and temperature during summer months at breeding grounds better predicted hematozoa prevalence than those that included annual migration distance or duration. Genetic diversity of blood parasites in populations of tundra swans appeared to be relative to hematozoa prevalence. Our results suggest ecological conditions at breeding grounds may explain differences of hematozoa infection among populations of tundra swans that breed in Alaska.

  2. Baseline hematology and clinical chemistry results from captive-raised trumpeter swans

    Science.gov (United States)

    Olsen, Glenn H.; Rininger, D.L.; Ets, M.K.; Sladen, William J. L.; Rees, Eileen C.; Earnst, Susan L.; Coulson, John C.

    2002-01-01

    Results from hematology and clinical chemistry tests are presented for healthy captive-raised Trumpeter Swans (Cygnus buccinator) to help establish baseline data. Blood samples were obtained from 14 cygnets between the ages of three to four and seven to eight months that were the subjects of a study to teach migration routes to swans. Males and females differed significantly in asparatate aminotransferase, alanine aminotransferase and total protein. Age categories differed significantly in hematocrit, white blood cell counts, alkaline phosphatase, aspar-rate aminotransferase, glucose, cholesterol and uric acid. There were no significant differences among age categories in values of alanine aminotransferase, calcium, triglycerides and total protein.

  3. Significance of the White Sea as a stopover for Bewick's Swans Cygnus columbianus bewickii in spring

    NARCIS (Netherlands)

    Nolet, BA; Andreev, VA; Clausen, P; Poot, MJM; Wessel, EGJ

    We searched for a major stopover site of Bewick's Swans Cygnus columbianus bewickii in the White Sea following the suggestion that one should exist on the stretch between Estonia and the breeding grounds (1750 km). We discovered 733 Swans in Dvina Bay during a late aerial survey in spring 1993.

  4. Hematology, plasma chemistry, and bacteriology of wild Tundra Swans (Cygnus columbianus) in Alaska.

    Science.gov (United States)

    Milani, Juliana F; Wilson, Heather; Ziccardi, Michael; LeFebvre, Rance; Scott, Cheryl

    2012-01-01

    Blood and cloacal swabs were collected from 100 (66 female, 34 male) wild Tundra Swans (Cygnus columbianus) molting in northwestern Alaska, USA, 25-28 July 2008, to establish hematologic and serum chemistry reference values and to isolate enteric Salmonella spp. and Escherichia coli O157:H7. Plasma biochemistry and hematology values did not vary significantly by sex or age. Tundra swans had high levels of creatine kinase, lactate dehydrogenase, amylase, and alkaline phosphatase compared with some other avian species (values were up to 7 times greater), possibly indicating capture myopathy. However, concentrations were much lower (up to 8 times lower) than in other waterfowl exposed to similar or more intensive capture methods. White blood cell count and hematocrit values were similar to other waterfowl species, and enteric Salmonella spp. and E. coli O157:H7 were not present among birds sampled. Our data provide the first biochemical, hematologic, and bacteriologic reference values for wild Tundra Swans.

  5. The RMI Space Weather and Navigation Systems (SWANS) Project

    Science.gov (United States)

    Warnant, Rene; Lejeune, Sandrine; Wautelet, Gilles; Spits, Justine; Stegen, Koen; Stankov, Stan

    The SWANS (Space Weather and Navigation Systems) research and development project (http://swans.meteo.be) is an initiative of the Royal Meteorological Institute (RMI) under the auspices of the Belgian Solar-Terrestrial Centre of Excellence (STCE). The RMI SWANS objectives are: research on space weather and its effects on GNSS applications; permanent mon-itoring of the local/regional geomagnetic and ionospheric activity; and development/operation of relevant nowcast, forecast, and alert services to help professional GNSS/GALILEO users in mitigating space weather effects. Several SWANS developments have already been implemented and available for use. The K-LOGIC (Local Operational Geomagnetic Index K Calculation) system is a nowcast system based on a fully automated computer procedure for real-time digital magnetogram data acquisition, data screening, and calculating the local geomagnetic K index. Simultaneously, the planetary Kp index is estimated from solar wind measurements, thus adding to the service reliability and providing forecast capabilities as well. A novel hybrid empirical model, based on these ground-and space-based observations, has been implemented for nowcasting and forecasting the geomagnetic index, issuing also alerts whenever storm-level activity is indicated. A very important feature of the nowcast/forecast system is the strict control on the data input and processing, allowing for an immediate assessment of the output quality. The purpose of the LIEDR (Local Ionospheric Electron Density Reconstruction) system is to acquire and process data from simultaneous ground-based GNSS TEC and digital ionosonde measurements, and subsequently to deduce the vertical electron density distribution. A key module is the real-time estimation of the ionospheric slab thickness, offering additional infor-mation on the local ionospheric dynamics. The RTK (Real Time Kinematic) status mapping provides a quick look at the small-scale ionospheric effects on the RTK

  6. Variation at the DRD4 locus is associated with wariness and local site selection in urban black swans.

    Science.gov (United States)

    van Dongen, Wouter F D; Robinson, Randall W; Weston, Michael A; Mulder, Raoul A; Guay, Patrick-Jean

    2015-12-11

    Interactions between wildlife and humans are increasing. Urban animals are often less wary of humans than their non-urban counterparts, which could be explained by habituation, adaptation or local site selection. Under local site selection, individuals that are less tolerant of humans are less likely to settle in urban areas. However, there is little evidence for such temperament-based site selection, and even less is known about its underlying genetic basis. We tested whether site selection in urban and non-urban habitats by black swans (Cygnus atratus) was associated with polymorphisms in two genes linked to fear in animals, the dopamine receptor D4 (DRD4) and serotonin transporter (SERT) genes. Wariness in swans was highly repeatable between disturbance events (repeatability = 0.61) and non-urban swans initiated escape from humans earlier than urban swans. We found no inter-individual variation in the SERT gene, but identified five DRD4 genotypes and an association between DRD4 genotype and wariness. Individuals possessing the most common DRD4 genotype were less wary than individuals possessing rarer genotypes. As predicted by the local site selection hypothesis, genotypes associated with wary behaviour were over three times more frequent at the non-urban site. This resulted in moderate population differentiation at DRD4 (FST = 0.080), despite the sites being separated by only 30 km, a short distance for this highly-mobile species. Low population differentiation at neutrally-selected microsatellite loci and the likely occasional migration of swans between the populations reduces the likelihood of local site adaptations. Our results suggest that wariness in swans is partly genetically-determined and that wary swans settle in less-disturbed areas. More generally, our findings suggest that site-specific management strategies may be necessary that consider the temperament of local animals.

  7. Commensal foraging with Bewick’s Swans Cygnus bewickii doubles instantaneous intake rate of Common Pochards Aythya ferina

    NARCIS (Netherlands)

    Gyimesi, A.; van Lith, B.; Nolet, B.A.

    2012-01-01

    Aquatically foraging Bewick’s Swans Cygnus bewickii have been repeatedly reported to be accompanied by diving ducks, but the exact nature of this relationship is unclear. Based on field observations, we found a strong correlation between the number of foraging swans and the number of foraging Common

  8. Blood chemistry of wild Brazilian Coscoroba Swans during molt.

    Science.gov (United States)

    Calabuig, Cecilia Pérez; Ferrer, Miguel; Muriel, Roberto

    2010-04-01

    The Coscoroba Swan (Coscoroba coscoroba) is an unusual member of the Anatidae found in South America, from the Falkland Islands and Tierra del Fuego through Chile and Argentina, Uruguay, and Paraguay as far north as Mato Grosso do Sul in Brazil. The species is not threatened globally, but some local populations have declined and the status of others is unknown. The objective of this study was to quantify the plasma chemistry of a wild population of Coscoroba Swans in southern Brazil during their molting period. We captured 12 chicks, 14 juveniles, and 31 mature birds. The following blood parameters were measured: glucose, cholesterol, triglycerides, HDL cholesterol, uric acid, creatine-kinase, aspartate amino transferase, alanine-aminotransferase, alkaline phosphatase, amylase, and pancreatic amylase. Significant differences between males and females were not observed for any of the parameters, and only the levels of alkaline phosphatase differed significantly among age groups.

  9. Therapist adherence in the strong without anorexia nervosa (SWAN) study: A randomized controlled trial of three treatments for adults with anorexia nervosa.

    Science.gov (United States)

    Andony, Louise J; Tay, Elaine; Allen, Karina L; Wade, Tracey D; Hay, Phillipa; Touyz, Stephen; McIntosh, Virginia V W; Treasure, Janet; Schmidt, Ulrike H; Fairburn, Christopher G; Erceg-Hurn, David M; Fursland, Anthea; Crosby, Ross D; Byrne, Susan M

    2015-12-01

    To develop a psychotherapy rating scale to measure therapist adherence in the Strong Without Anorexia Nervosa (SWAN) study, a multi-center randomized controlled trial comparing three different psychological treatments for adults with anorexia nervosa. The three treatments under investigation were Enhanced Cognitive Behavioural Therapy (CBT-E), the Maudsley Anorexia Nervosa Treatment for Adults (MANTRA), and Specialist Supportive Clinical Management (SSCM). The SWAN Psychotherapy Rating Scale (SWAN-PRS) was developed, after consultation with the developers of the treatments, and refined. Using the SWAN-PRS, two independent raters initially rated 48 audiotapes of treatment sessions to yield inter-rater reliability data. One rater proceeded to rate a total of 98 audiotapes from 64 trial participants. The SWAN-PRS demonstrated sound psychometric properties, and was considered a reliable measure of therapist adherence. The three treatments were highly distinguishable by independent raters, with therapists demonstrating significantly more behaviors consistent with the actual allocated treatment compared to the other two treatment modalities. There were no significant site differences in therapist adherence observed. The findings provide support for the internal validity of the SWAN study. The SWAN-PRS was deemed suitable for use in other trials involving CBT-E, MANTRA, or SSCM. The Authors. International Journal of Eating Disorders Published by Wiley Periodicals, Inc.

  10. Migration of whooper swans and outbreaks of highly pathogenic avian influenza H5N1 virus in eastern Asia.

    Directory of Open Access Journals (Sweden)

    Scott H Newman

    Full Text Available Evaluating the potential involvement of wild avifauna in the emergence of highly pathogenic avian influenza H5N1 (hereafter H5N1 requires detailed analyses of temporal and spatial relationships between wild bird movements and disease emergence. The death of wild swans (Cygnus spp. has been the first indicator of the presence of H5N1 in various Asian and European countries; however their role in the geographic spread of the disease remains poorly understood. We marked 10 whooper swans (Cygnus cygnus with GPS transmitters in northeastern Mongolia during autumn 2006 and tracked their migratory movements in relation to H5N1 outbreaks. The prevalence of H5N1 outbreaks among poultry in eastern Asia during 2003-2007 peaked during winter, concurrent with whooper swan movements into regions of high poultry density. However outbreaks involving poultry were detected year round, indicating disease perpetuation independent of migratory waterbird presence. In contrast, H5N1 outbreaks involving whooper swans, as well as other migratory waterbirds that succumbed to the disease in eastern Asia, tended to occur during seasons (late spring and summer and in habitats (areas of natural vegetation where their potential for contact with poultry is very low to nonexistent. Given what is known about the susceptibility of swans to H5N1, and on the basis of the chronology and rates of whooper swan migration movements, we conclude that although there is broad spatial overlap between whooper swan distributions and H5N1 outbreak locations in eastern Asia, the likelihood of direct transmission between these groups is extremely low. Thus, our data support the hypothesis that swans are best viewed as sentinel species, and moreover, that in eastern Asia, it is most likely that their infections occurred through contact with asymptomatic migratory hosts (e.g., wild ducks at or near their breeding grounds.

  11. Population estimates and geographical distributions of swans and geese in East Asia based on counts during the non-breeding season

    DEFF Research Database (Denmark)

    Jia, Qiang; Koyama, Kazuo; Choi, Chang-Yong

    2016-01-01

    For the first time, we estimated the population sizes of two swan species and four goose species from observations during the non-breeding period in East Asia. Based on combined counts from South Korea, Japan and China, we estimated the total abundance of these species as follows: 42,000–47,000 W......For the first time, we estimated the population sizes of two swan species and four goose species from observations during the non-breeding period in East Asia. Based on combined counts from South Korea, Japan and China, we estimated the total abundance of these species as follows: 42......,000–47,000 Whooper Swans Cygnus cygnus ; 99,000–141,000 Tundra Swans C. columbianus bewickii ; 56,000–98,000 Swan Geese Anser cygnoides ; 157,000–194,000 Bean Geese A. fabalis ; 231,000–283,000 Greater White-fronted Geese A. albifrons ; and 14,000–19,000 Lesser White-fronted Geese A. erythropus. While the count data...... from Korea and Japan provide a good reflection of numbers present, there remain gaps in the coverage in China, which particularly affect the precision of the estimates for Bean, Greater and Lesser White-fronted Geese as well as Tundra Swans. Lack of subspecies distinction of Bean Geese in China until...

  12. 77 FR 31843 - Swan Lake North Hydro, LLC; Notice of Preliminary Permit Application Accepted For Filing and...

    Science.gov (United States)

    2012-05-30

    ... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 13318-002] Swan Lake North Hydro, LLC; Notice of Preliminary Permit Application Accepted For Filing and Soliciting Comments, Motions to Intervene, and Competing Applications On April 3, 2012, Swan Lake North Hydro, LLC, filed an application for a successive preliminary permit...

  13. Prevalence of long QT syndrome and other cardiac defects in deaf-mute children

    International Nuclear Information System (INIS)

    Niaz, A.; Rizvi, S.F.U.; Khurram, D.

    2011-01-01

    Background: Long QT syndrome is considered a fatal disease because of its association with ventricular arrhythmias and sudden cardiac death. Objectives of study were to determine the prevalence of long QT syndrome and other heart diseases, in deaf-mute children. Methods: A Cross-sectional descriptive study was conducted at Cholistan special education centre and Cardiology department, Sheikh Zayed hospital Rahim Yar Khan, Pakistan in September 2006. A total of 104 congenitally deaf-mute children were assessed. Height, weight and blood pressure measured, 12-lead electrocardiogram done and QTc calculated using Bazette's formula. Children with prolonged QTc underwent 24-hour ambulatory ECG recording. All were auscultated following complete protocol. A child with murmur was further evaluated with colour Doppler echocardiography. Audiometry was performed on all the children and the result interpreted according to WHO recommendations. Diagnosis of LQTS was based on Revised Schwartz criteria. Results: Out of 104 children, 62 were male with mean age 11.89 yrs. The average systolic and diastolic BP was 97/67 mmHg. Average height was 126 Cm. All children had moderate to severe bilateral sensorineural hearing loss (40-80 dB). One child had associated Patent Ductus Arteriosis. Fifteen had an innocent murmur. Prevalence of congenital heart disease was found to be 0.1/1000. Four children had QT interval more than 440 mSec, (range 0.46-0.47 mSec.). Both genders were equally affected. Three children had high probability of LQTS and one had intermediate probability. Screening of family of these 4 patients showed prolonged QT interval in the sibling of one patient. Conclusion: Our study highlights the significant prevalence of Jervell Lange-Nielsen Syndrome in Pakistani deaf-mute children, which may be associated to the high level of consanguinity in this region. Awareness of this syndrome among health care providers is needed as timely diagnosis and subsequent treatment may prevent

  14. Coil Embolization Treatment in Pulmonary Artery Branch Rupture During Swan-Ganz Catheterization

    International Nuclear Information System (INIS)

    Gottwalles, Yannick; Wunschel-Joseph, Marie-Eve; Hanssen, Michel

    2000-01-01

    Rupture of the pulmonary artery or one of its branches during Swan-Ganz catheterization is a complication that is rare but remains fatal in almost 50% of cases. The risk factors and mechanisms involved in the pathogenesis of this accident have been widely reported. Management is twofold: resuscitation procedures and specific medical or even surgical treatment. We report a case of pulmonary artery rupture occurring during Swan-Ganz catheterization that was treated by coil embolization. This technique, which is quick and simple to use, would appear to be very promising. This is the first case of successful emergency treatment of pulmonary artery rupture using an endovascular technique

  15. Black Swans and Many Worlds: Contemporary models in music, the arts and ideas

    Directory of Open Access Journals (Sweden)

    Barry Barbara

    2013-01-01

    Full Text Available Black Swans and Many Worlds are new models to help explain musical structures, and by extension, events in the social environment and in internal human experience. Many Worlds takes its departure point from quantum physics, and especially the work of Hugh Everett III, who used the defining point of a measurement in the sub-atomic world as initiating alternative courses of action. Everett extrapolated this idea to the macro-world: a defining point may initiate multiple outcomes, each with its own character and events, as parallel worlds. One application of this model is to consider musical works within a genre as Many Worlds. Black Swans derive from Nassim Taleb, who proposes that social, political, and in fact all aspects of today’s world are not understandable by logical processes or incremental change but are often rocked by extreme, unpredictable shocks. If Many Worlds provide new ways of thinking about potentiality, probability and innovation, Black Swans arrest us in our tracks by eruptions that threaten to derail contemporary life, and with it, music, the arts and ideas.

  16. Development and applications of the SWAN rating scale for assessment of attention deficit hyperactivity disorder: a literature review.

    Science.gov (United States)

    Brites, C; Salgado-Azoni, C A; Ferreira, T L; Lima, R F; Ciasca, S M

    2015-11-01

    This study reviewed the use of the Strengths and Weaknesses of Attention-Deficit/Hyperactivity-symptoms and Normal-behaviors (SWAN) rating scale in diagnostic and evolutive approaches to attention deficit hyperactivity disorder (ADHD) and in correlational studies of the disorder. A review of articles published in indexed journals from electronic databases was conducted and 61 articles on the SWAN scale were analyzed. From these, 27 were selected to a) examine use of SWAN in research on attention disorders and b) verify evidence of its usefulness in the areas of genetics, neuropsychology, diagnostics, psychiatric comorbidities, neuroimaging, pharmacotherapy, and to examine its statistical reliability and validity in studies of diverse populations. This review of articles indicated a growing use of the SWAN scale for diagnostic purposes, for therapy, and in research on areas other than ADHD, especially when compared with other reliable scales. Use of the scale in ADHD diagnosis requires further statistical testing to define its psychometric properties.

  17. Development and applications of the SWAN rating scale for assessment of attention deficit hyperactivity disorder: a literature review

    Directory of Open Access Journals (Sweden)

    C. Brites

    2015-11-01

    Full Text Available This study reviewed the use of the Strengths and Weaknesses of Attention-Deficit/Hyperactivity-symptoms and Normal-behaviors (SWAN rating scale in diagnostic and evolutive approaches to attention deficit hyperactivity disorder (ADHD and in correlational studies of the disorder. A review of articles published in indexed journals from electronic databases was conducted and 61 articles on the SWAN scale were analyzed. From these, 27 were selected to a examine use of SWAN in research on attention disorders and b verify evidence of its usefulness in the areas of genetics, neuropsychology, diagnostics, psychiatric comorbidities, neuroimaging, pharmacotherapy, and to examine its statistical reliability and validity in studies of diverse populations. This review of articles indicated a growing use of the SWAN scale for diagnostic purposes, for therapy, and in research on areas other than ADHD, especially when compared with other reliable scales. Use of the scale in ADHD diagnosis requires further statistical testing to define its psychometric properties.

  18. Swan: A tool for porting CUDA programs to OpenCL

    Science.gov (United States)

    Harvey, M. J.; De Fabritiis, G.

    2011-04-01

    The use of modern, high-performance graphical processing units (GPUs) for acceleration of scientific computation has been widely reported. The majority of this work has used the CUDA programming model supported exclusively by GPUs manufactured by NVIDIA. An industry standardisation effort has recently produced the OpenCL specification for GPU programming. This offers the benefits of hardware-independence and reduced dependence on proprietary tool-chains. Here we describe a source-to-source translation tool, "Swan" for facilitating the conversion of an existing CUDA code to use the OpenCL model, as a means to aid programmers experienced with CUDA in evaluating OpenCL and alternative hardware. While the performance of equivalent OpenCL and CUDA code on fixed hardware should be comparable, we find that a real-world CUDA application ported to OpenCL exhibits an overall 50% increase in runtime, a reduction in performance attributable to the immaturity of contemporary compilers. The ported application is shown to have platform independence, running on both NVIDIA and AMD GPUs without modification. We conclude that OpenCL is a viable platform for developing portable GPU applications but that the more mature CUDA tools continue to provide best performance. Program summaryProgram title: Swan Catalogue identifier: AEIH_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEIH_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: GNU Public License version 2 No. of lines in distributed program, including test data, etc.: 17 736 No. of bytes in distributed program, including test data, etc.: 131 177 Distribution format: tar.gz Programming language: C Computer: PC Operating system: Linux RAM: 256 Mbytes Classification: 6.5 External routines: NVIDIA CUDA, OpenCL Nature of problem: Graphical Processing Units (GPUs) from NVIDIA are preferentially programed with the proprietary CUDA programming toolkit. An

  19. Potential disease transmission from wild geese and swans to livestock, poultry and humans: a review of the scientific literature from a One Health perspective.

    Science.gov (United States)

    Elmberg, Johan; Berg, Charlotte; Lerner, Henrik; Waldenström, Jonas; Hessel, Rebecca

    2017-01-01

    There are more herbivorous waterfowl (swans and geese) close to humans, livestock and poultry than ever before. This creates widespread conflict with agriculture and other human interests, but also debate about the role of swans and geese as potential vectors of disease of relevance for human and animal health. Using a One Health perspective, we provide the first comprehensive review of the scientific literature about the most relevant viral, bacterial, and unicellular pathogens occurring in wild geese and swans. Research thus far suggests that these birds may play a role in transmission of avian influenza virus, Salmonella, Campylobacter , and antibiotic resistance. On the other hand, at present there is no evidence that geese and swans play a role in transmission of Newcastle disease, duck plague, West Nile virus, Vibrio, Yersinia, Clostridium, Chlamydophila , and Borrelia . Finally, based on present knowledge it is not possible to say if geese and swans play a role in transmission of Escherichia coli, Pasteurella, Helicobacter, Brachyspira, Cryptosporidium, Giardia , and Microsporidia. This is largely due to changes in classification and taxonomy, rapid development of identification methods and lack of knowledge about host specificity. Previous research tends to overrate the role of geese and swans as disease vectors; we do not find any evidence that they are significant transmitters to humans or livestock of any of the pathogens considered in this review. Nevertheless, it is wise to keep poultry and livestock separated from small volume waters used by many wild waterfowl, but there is no need to discourage livestock grazing in nature reserves or pastures where geese and swans are present. Under some circumstances it is warranted to discourage swans and geese from using wastewater ponds, drinking water reservoirs, and public beaches. Intensified screening of swans and geese for AIV, West Nile virus and anatid herpesvirus is warranted.

  20. Clinical utility of the Chinese Strengths and Weaknesses of ADHD-Symptoms and Normal-behaviors questionnaire (SWAN when compared with DISC-IV

    Directory of Open Access Journals (Sweden)

    Chan GFC

    2014-08-01

    Full Text Available Grace Fong-Chun Chan,1 Kelly Yee-Ching Lai,2 Ernest Siu-Luen Luk,3 Se-Fong Hung,2 Patrick Wing-Leung Leung4 1Department of Psychiatry, Alice Ho Miu Ling Nethersole Hospital, 2Department of Psychiatry, The Chinese University of Hong Kong, 3Private practice, 4Clinical and Health Psychology Centre, Department of Psychology, The Chinese University of Hong Kong, Hong Kong Special Administrative Region Background: Attention-deficit/hyperactivity disorder (ADHD is a common and impairing child and adolescent psychiatric disorder. Early identification and prompt treatment are essential. Rating scales are commonly used by clinicians and researchers to assess ADHD children. Objective: In the current study, we aimed to examine the clinical utility of the Chinese version of the Strengths and Weaknesses of ADHD Symptoms and Normal Behaviors (SWAN questionnaire. We validated its subscale scores against the Diagnostic Interview Schedule for Children Version IV (DISC-IV and looked into its ability to identify ADHD in a psychiatric clinic setting. We also tested age and gender effects on SWAN scores. Specific subscale cutoff scores of SWAN were subsequently determined.Method: A total of 290 children aged 6–12 years old studying in local mainstream primary schools were recruited from a clinic setting and interviewed with the parent version of DISC-IV. Their parents and teachers completed the corresponding version of SWAN.Results: Both parent and teacher versions of SWAN were found to have good concurrent validity with DISC-IV. It could identify ADHD well in a clinic sample. Gender-specific cutoff scores were determined. Sensitivities and specificities were found to be satisfactory. SWAN was also found to perform equally well in identifying ADHD in those with and without comorbid Autistic Spectrum Disorder.Conclusion: SWAN was proven to be a useful tool to aid the assessment of ADHD in a clinic sample. Keywords: ADHD, SWAN, DISC-IV, validity

  1. The use of a wave boundary layer model in SWAN

    DEFF Research Database (Denmark)

    Du, Jianting; Bolaños, Rodolfo; Larsén, Xiaoli Guo

    2017-01-01

    A Wave Boundary Layer Model (WBLM) is implemented in the third-generation ocean wave model SWAN to improve the wind-input source function under idealized, fetch-limited condition. Accordingly, the white capping dissipation parameters are re-calibrated to fit the new wind-input source function...

  2. Ancient DNA and morphometric analysis reveal extinction and replacement of New Zealand's unique black swans.

    Science.gov (United States)

    Rawlence, Nicolas J; Kardamaki, Afroditi; Easton, Luke J; Tennyson, Alan J D; Scofield, R Paul; Waters, Jonathan M

    2017-07-26

    Prehistoric human impacts on megafaunal populations have dramatically reshaped ecosystems worldwide. However, the effects of human exploitation on smaller species, such as anatids (ducks, geese, and swans) are less clear. In this study we apply ancient DNA and osteological approaches to reassess the history of Australasia's iconic black swans ( Cygnus atratus ) including the palaeo-behaviour of prehistoric populations. Our study shows that at the time of human colonization, New Zealand housed a genetically, morphologically, and potentially ecologically distinct swan lineage ( C. sumnerensis , Poūwa), divergent from modern (Australian) C. atratus Morphological analyses indicate C. sumnerensis exhibited classic signs of the 'island rule' effect, being larger, and likely flight-reduced compared to C. atratus Our research reveals sudden extinction and replacement events within this anatid species complex, coinciding with recent human colonization of New Zealand. This research highlights the role of anthropogenic processes in rapidly reshaping island ecosystems and raises new questions for avian conservation, ecosystem re-wilding, and de-extinction. © 2017 The Author(s).

  3. SWAN-PPL, Fusion Reactor 1-D Particle Transport Optimization

    International Nuclear Information System (INIS)

    Levin, P.; Greenspan, E.

    1989-01-01

    1 - Description of problem or function: Given the material density profiles which describe a one-dimensional reference system with a neutron source, SWAN will calculate, and optionally implement, density changes so as to optimize a single functional parameter of the system. 2 - Method of solution: The one-dimensional discrete-ordinate transport code ANISN is used to calculate flux and adjoint distributions for specified sources. The code SWIF calculates first-order estimates of the effect of material density changes on a goal functional, and from these evaluates effectiveness functions for the substitution of one material for another. Density distribution changes are then calculated which would optimize the goal functional, optionally subject to a constraint of holding another functional constant (to first order). 3 - Restrictions on the complexity of the problem: SWAN is not designed to analyze critical systems; it assumes that there is a fixed source, as in shielding or fusion reactor applications. Otherwise it is compatible with ANISN. All arrays are variably-dimensioned, so that there are no restrictions on individual dimensions

  4. Emerging risk – Conceptual definition and a relation to black swan type of events

    International Nuclear Information System (INIS)

    Flage, R.; Aven, T.

    2015-01-01

    The concept of emerging risk has gained increasing attention in recent years. The term has an intuitive appeal and meaning but a consistent and agreed definition is missing. We perform an in-depth analysis of this concept, in particular its relation to black swan type of events, and show that these can be considered meaningful and complementary concepts by relating emerging risk to known unknowns and black swans to unknown knowns, unknown unknowns and a subset of known knowns. The former is consistent with saying that we face emerging risk related to an activity when the background knowledge is weak but contains indications/justified beliefs that a new type of event (new in the context of that activity) could occur in the future and potentially have severe consequences to something humans value. The weak background knowledge among other things results in difficulty specifying consequences and possibly also in fully specifying the event itself; i.e. in difficulty specifying scenarios. Here knowledge becomes the key concept for both emerging risk and black swan type of events, allowing for taking into consideration time dynamics since knowledge develops over time. Some implications of our findings in terms of risk assessment and risk management are pointed out. - Highlights: • We perform an in-depth analysis of the concept of emerging risk. • Emerging risk and black swan type of events are shown to be complementary concepts. • We propose a definition of emerging risk where knowledge becomes the key term. • Some implications for risk assessment and risk management are pointed out.

  5. Migratory Whooper Swans Cygnus cygnus Transmit H5N1 Virus between China and Mongolia: Combination Evidence from Satellite Tracking and Phylogenetics Analysis.

    Science.gov (United States)

    Li, Shuhong; Meng, Weiyue; Liu, Dongping; Yang, Qiqi; Chen, Lixia; Dai, Qiang; Ma, Tian; Gao, Ruyi; Ru, Wendong; Li, Yunfeng; Yu, Pengbo; Lu, Jun; Zhang, Guogang; Tian, Huaiyu; Chai, Hongliang; Li, Yanbing

    2018-05-04

    In late 2014, a highly pathogenic avian influenza (hereafter HPAI) H5N1 outbreak infected whooper swans Cygnus cygnus wintering at the Sanmenxia Reservoir area, China, and raised concerns about migratory linkages between wintering and breeding grounds of whooper swans. In this study, 61 swans were satellite tracked from 2013 to 2016 to determine the spatial association of their migration routes and H5N1 outbreaks, and 3596 fecal samples were collected along the migration routes for virology testing. Swans departed the wintering grounds and migrated along the Yellow River, and flew over the Yin Mountains in China. The Brownian bridge movement model showed there was a high degree of spatiotemporal overlap between the core use area along the spring migration pathway and historical H5N1 events in China and Mongolia from 2005 to 2015. The H5N1 strain was isolated and phylogenetic analyses confirmed that the HA gene sequence generated is genetically similar to that of the epidemic strain at a previous wintering site (the Sanmenxia Reservoir area) along its flyway. Our results identified a previously unknown migratory link of whooper swans in central China with Mongolia and confirmed that the swans could carry the HPAI H5N1 virus during migration, resulting in long-distance transmission.

  6. Risk, surprises and black swans fundamental ideas and concepts in risk assessment and risk management

    CERN Document Server

    Aven, Terje

    2014-01-01

    Risk, Surprises and Black Swans provides an in depth analysis of the risk concept with a focus on the critical link to knowledge; and the lack of knowledge, that risk and probability judgements are based on.Based on technical scientific research, this book presents a new perspective to help you understand how to assess and manage surprising, extreme events, known as 'Black Swans'. This approach looks beyond the traditional probability-based principles to offer a broader insight into the important aspects of uncertain events and in doing so explores the ways to manage them.

  7. Pharmacokinetics, bioavailability and dose assessment of Cefquinome against Escherichia coli in black swans (Cygnus atratus).

    Science.gov (United States)

    Zhao, Dong-Hao; Wang, Xu-Feng; Wang, Qiang; Li, Liu-Dong

    2017-07-28

    The objective of this study is to investigate pharmacokinetics and dose regimens of cefquinome in black swans following intravenous (IV) and intramuscular (IM) administration at a single dose of 2 mg/kg. The MICs of cefquinome against 49 Escherichia coli isolates from black swans were determined. Monte Carlo simulation was applied to conduct the dose regimen assessment and optimization of cefquinome against E. coli in black swans, and a pharmacokinetic/pharmacodynamic (PK/PD) cutoff was established for E. coli isolates obtained in this study. The PK parameters of T 1/2α (0.31 h), T 1/2β (1.69 h) and Cl B (0.13 L/kg·h) indicated a rapid distribution and elimination of cefquinome in black swans after IV administration. After IM injection, the corresponding PK parameters of T 1/2Ka , T 1/2Ke , T max , C max , and F were 0.12 h, 1.62 h, 0.39 h, 5.71 μg/mL and 74.2%, respectively. The MICs of cefquinome against black swans E. coli ranged from 0.03 to 8 μg/mL, with MIC 50 and MIC 90 of 0.06 and 0.5 μg/mL, respectively. The PK/PD cutoff of cefquinome against E. coli was determined to be 0.2 μg/mL. Monte Carlo simulation showed that the nominal dose regimen (2 mg/kg/24 h) could not achieve a satisfactory probability of target attainment (PTA) for %T MIC  ≥ 50%, indicating a risk of treatment failure and the development of potential drug resistance. The current daily dosage of cefquinome when divided into 12-h interval (1 mg/kg/12 h) may be effective for the treatment of E. coli infections with an MIC ≤0.5 μg/mL.

  8. Bewick's Swans refuelling on pondweed tubers in the Dvina Bay (White Sea) during their spring migration: first come, first served

    NARCIS (Netherlands)

    Nolet, B.A.; Drent, R.H.

    1998-01-01

    Current models of bird migration consider the optimal decision making of individuals irrespective of the behaviour of conspecifics. We observed the foraging behaviour of Bewick's Swans Cygnus columbianus during their stop-over in the Dvina Bay in the White Sea in spring 1995 and 1996. Here the swans

  9. Bewick's Swans refuelling on pondweed tubers in the Dvina Bay (White Sea) during their spring migration : first come, first served

    NARCIS (Netherlands)

    Nolet, BA; Drent, RH

    1998-01-01

    Current models of bird migration consider the optimal decision making of individuals irrespective of the behaviour of conspecifics. We observed the foraging behaviour of Bewick's Swans Cygnus columbianus during their stop-over in the Dvina Bay in the White Sea in spring 1995 and 1996. Here the swans

  10. Black swan risk management : The moderation effect of risk mitigation strategies

    NARCIS (Netherlands)

    Zhu, Q; Krikke, H.R.; Caniels, M.C.J.; Pawar, K.S.; Rogers, H.

    2013-01-01

    Many scholars have discussed supply chain risk mitigation on operational risks, but less on rare, highly influential, and retrospective predictable risks, such as natural disasters, epidemics, and socio-political crises. They are Black Swan risks (Taleb, 2007). More than disrupting supply chains,

  11. SWAN - Detection of explosives by means of fast neutron activation analysis

    International Nuclear Information System (INIS)

    Gierlik, M.; Borsuk, S.; Guzik, Z.; Iwanowska, J.; Kaźmierczak, Ł.; Korolczuk, S.; Kozłowski, T.; Krakowski, T.; Marcinkowski, R.; Swiderski, L.; Szeptycka, M.; Szewiński, J.; Urban, A.

    2016-01-01

    In this work we report on SWAN, the experimental, portable device for explosives detection. The device was created as part of the EU Structural Funds Project “Accelerators & Detectors” (POIG.01.01.02-14-012/08-00), with the goal to increase beneficiary's expertise and competencies in the field of neutron activation analysis. Previous experiences and budged limitations lead toward a less advanced design based on fast neutron interactions and unsophisticated data analysis with the emphasis on the latest gamma detection and spectrometry solutions. The final device has been designed as a portable, fast neutron activation analyzer, with the software optimized for detection of carbon, nitrogen and oxygen. SWAN's performance in the role of explosives detector is elaborated in this paper. We demonstrate that the unique features offered by neutron activation analysis might not be impressive enough when confronted with practical demands and expectations of a generic homeland security customer.

  12. The Use of Simulation to Reduce the Domain of "Black Swans" with Application to Hurricane Impacts to Power Systems.

    Science.gov (United States)

    Berner, Christine L; Staid, Andrea; Flage, Roger; Guikema, Seth D

    2017-10-01

    Recently, the concept of black swans has gained increased attention in the fields of risk assessment and risk management. Different types of black swans have been suggested, distinguishing between unknown unknowns (nothing in the past can convincingly point to its occurrence), unknown knowns (known to some, but not to relevant analysts), or known knowns where the probability of occurrence is judged as negligible. Traditional risk assessments have been questioned, as their standard probabilistic methods may not be capable of predicting or even identifying these rare and extreme events, thus creating a source of possible black swans. In this article, we show how a simulation model can be used to identify previously unknown potentially extreme events that if not identified and treated could occur as black swans. We show that by manipulating a verified and validated model used to predict the impacts of hazards on a system of interest, we can identify hazard conditions not previously experienced that could lead to impacts much larger than any previous level of impact. This makes these potential black swan events known and allows risk managers to more fully consider them. We demonstrate this method using a model developed to evaluate the effect of hurricanes on energy systems in the United States; we identify hurricanes with potentially extreme impacts, storms well beyond what the historic record suggests is possible in terms of impacts. © 2016 Society for Risk Analysis.

  13. Society environmental economic benefits of swan-labelled workwear service

    DEFF Research Database (Denmark)

    Grüttner, Henrik; Dall, Ole; Thomsen, Henning

    2011-01-01

    This paper presents an environmental and socio-economic comparison of textile supply of workwear with and without the Nordic Swan labelling scheme. The study is part of a project for development of a methodology for the environmental and socio-economic comparison for product groups. The study...... is transferred into economic impacts demonstrating a substantial saving for the society when purchasing the eco-labelled service....

  14. Mutual ornamentation, sexual selection, and social dominance in the black swan

    NARCIS (Netherlands)

    Kraaijeveld, K; Gregurke, J; Hall, C; Komdeur, J; Mulder, RA

    We investigated the adaptive significance of a sexually monomorphic ornament in the black swan Cygnus atratus. Both sexes grow curled feathers on their wings (range 7-22 curled feathers per wing), which are displayed prominently in a range of social interactions. The number of curled feathers

  15. Canards and black swans in a model of a 3-D autocatalator

    Science.gov (United States)

    Shchepakina, E.

    2005-01-01

    The mathematical model of a 3-D autocatalator is studied using the geometric theory of singular perturbations, namely, the black swan and canard techniques. Critical regimes are modeled by canards (one-dimensional stable-unstable slow integral manifolds). The meaning of criticality here is as follows. The critical regime corresponds to a chemical reaction which separates the domain of self-accelerating reactions from the domain of slow reactions. A two-dimensional stable-unstable slow integral manifold (black swan) consisting entirely of canards, which simulate the critical phenomena for different initial data of the dynamical system, is constructed. It is shown that this procedure leads to the phenomenon of auto-oscillations in the chemical system. The geometric approach combined with asymptotic and numerical methods permits us to explain the strong parametric sensitivity and to obtain asymptotic representations of the critical behavior of the chemical system.

  16. Canards and black swans in a model of a 3-D autocatalator

    International Nuclear Information System (INIS)

    Shchepakina, E

    2005-01-01

    The mathematical model of a 3-D autocatalator is studied using the geometric theory of singular perturbations, namely, the black swan and canard techniques. Critical regimes are modeled by canards (one-dimensional stable-unstable slow integral manifolds). The meaning of criticality here is as follows. The critical regime corresponds to a chemical reaction which separates the domain of self-accelerating reactions from the domain of slow reactions. A two-dimensional stable-unstable slow integral manifold (black swan) consisting entirely of canards, which simulate the critical phenomena for different initial data of the dynamical system, is constructed. It is shown that this procedure leads to the phenomenon of auto-oscillations in the chemical system. The geometric approach combined with asymptotic and numerical methods permits us to explain the strong parametric sensitivity and to obtain asymptotic representations of the critical behavior of the chemical system

  17. SWAN - Detection of explosives by means of fast neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Gierlik, M., E-mail: m.gierlik@ncbj.gov.pl; Borsuk, S.; Guzik, Z.; Iwanowska, J.; Kaźmierczak, Ł.; Korolczuk, S.; Kozłowski, T.; Krakowski, T.; Marcinkowski, R.; Swiderski, L.; Szeptycka, M.; Szewiński, J.; Urban, A.

    2016-10-21

    In this work we report on SWAN, the experimental, portable device for explosives detection. The device was created as part of the EU Structural Funds Project “Accelerators & Detectors” (POIG.01.01.02-14-012/08-00), with the goal to increase beneficiary's expertise and competencies in the field of neutron activation analysis. Previous experiences and budged limitations lead toward a less advanced design based on fast neutron interactions and unsophisticated data analysis with the emphasis on the latest gamma detection and spectrometry solutions. The final device has been designed as a portable, fast neutron activation analyzer, with the software optimized for detection of carbon, nitrogen and oxygen. SWAN's performance in the role of explosives detector is elaborated in this paper. We demonstrate that the unique features offered by neutron activation analysis might not be impressive enough when confronted with practical demands and expectations of a generic homeland security customer.

  18. Gender equity programmes in academic medicine: a realist evaluation approach to Athena SWAN processes.

    Science.gov (United States)

    Caffrey, Louise; Wyatt, David; Fudge, Nina; Mattingley, Helena; Williamson, Catherine; McKevitt, Christopher

    2016-09-08

    Gender inequity has persisted in academic medicine. Yet equity is vital for countries to achieve their full potential in terms of translational research and patient benefit. This study sought to understand how the gender equity programme, Athena SWAN, can be enabled and constrained by interactions between the programme and the context it is implemented into, and whether these interactions might produce unintended consequences. Multimethod qualitative case studies using a realist evaluation approach. 5 departments from a university medical school hosting a Translational Research Organisation. 25 hours of observations of gender equality committee meetings, 16 in-depth interviews with Heads of Departments, Committee Leads and key personnel involved in the initiative. 4 focus groups with 15 postdoctoral researchers, lecturers and senior lecturers. The implementation of Athena SWAN principles was reported to have created social space to address gender inequity and to have highlighted problematic practices to staff. However, a number of factors reduced the programme's potential to impact gender inequity. Gender inequity was reproduced in the programme's enactment as female staff was undertaking a disproportionate amount of Athena SWAN work, with potential negative impacts on individual women's career progression. Early career researchers experienced problems accessing Athena SWAN initiatives. Furthermore, the impact of the programme was perceived to be undermined by wider institutional practices, national policies and societal norms, which are beyond the programme's remit. Gender equity programmes have the potential to address inequity. However, paradoxically, they can also unintentionally reproduce and reinforce gender inequity through their enactment. Potential programme impacts may be undermined by barriers to staff availing of career development and training initiatives, and by wider institutional practices, national policies and societal norms. Published by the

  19. A rangewide population genetic study of trumpeter swans

    Science.gov (United States)

    Oyler-McCance, S.J.; Ransler, F.A.; Berkman, L.K.; Quinn, T.W.

    2007-01-01

    For management purposes, the range of naturally occurring trumpeter swans (Cygnus buccinator) has been divided into two populations, the Pacific Coast Population (PP) and the Rocky Mountain Population (RMP). Little is known about the distribution of genetic variation across the species' range despite increasing pressure to make difficult management decisions regarding the two populations and flocks within them. To address this issue, we used rapidly evolving genetic markers (mitochondrial DNA sequence and 17 nuclear microsatellite loci) to elucidate the underlying genetic structure of the species. Data from both markers revealed a significant difference between the PP and RMP with the Yukon Territory as a likely area of overlap. Additionally, we found that the two populations have somewhat similar levels of genetic diversity (PP is slightly higher) suggesting that the PP underwent a population bottleneck similar to a well-documented one in the RMP. Both genetic structure and diversity results reveal that the Tri-State flock, a suspected unique, non-migratory flock, is not genetically different from the Canadian flock of the RMP and need not be treated as a unique population from a genetic standpoint. Finally, trumpeter swans appear to have much lower mitochondrial DNA variability than other waterfowl studied thus far which may suggest a previous, species-wide bottleneck. ?? 2007 Springer Science+Business Media, Inc.

  20. Migrating swans profit from favourable changes in wind conditions at low altitude

    NARCIS (Netherlands)

    Klaassen, M; Beekman, JH; Kontiokorpi, J; Mulder, RJW; Nolet, BA

    Because energy reserves limit flight range, wind assistance may be of crucial importance for migratory birds. We tracked eight Bewick's swans Cygnus columbianus bewickii, using 95-g satellite transmitters with altimeters and activity sensors, during their spring migration from Denmark to northern

  1. Migrating swans profit from favourable changes in wind conditions at low altitude

    NARCIS (Netherlands)

    Klaassen, M.R.J.; Beekman, J.H.; Kontiokorpi, J.; Mulder, R.J.W.; Nolet, B.A.

    2004-01-01

    Because energy reserves limit flight range, wind assistance may be of crucial importance for migratory birds. We tracked eight Bewicks swans Cygnus columbianus bewickii, using 95-g satellite transmitters with altimeters and activity sensors, during their spring migration from Denmark to northern

  2. The effect of lead poisoning on hematologic and biochemical values in trumpeter swans and Canada geese.

    Science.gov (United States)

    Katavolos, P; Staempfli, S; Sears, W; Gancz, A Y; Smith, D A; Bienzle, D

    2007-12-01

    Lead is a persistent contaminant in the environment, and waterfowl are susceptible to lead toxicity from ingestion of lead pellets and fishing weights. Lead affects numerous physiologic processes through inhibition of enzyme activity and protein function, but its effects on commonly assessed avian blood values are incompletely understood. Our aim was to evaluate hematologic and biochemical changes associated with blood lead concentrations in trumpeter swans and Canada geese. Data for CBCs, plasma biochemical profiles (total protein, albumin, glucose, cholesterol, total bilirubin, calcium, phosphorus, gamma-glutamyltransferase [GGT], aspartate aminotransferase, lactate dehydrogenase, glutamate dehydrogenase, creatine kinase, amylase, and lipase), and whole blood lead concentrations were retrospectively analyzed for 69 trumpeter swans and 52 Canada geese. Laboratory data obtained prospectively from an additional 20 trumpeter swans also were included. RBC morphology was semiquantitated in blood smears from 70 of the birds. Data were analyzed initially by ANOVA and covariance. A statistical model then was constructed to determine the relationship between each parameter and lead concentration. In both avian species, PCV, hemoglobin concentration, and MCHC decreased significantly (P < .05) with increasing blood lead concentration. Uric acid concentration and GGT activity were increased in trumpeter swans and phosphorus concentration was decreased in Canada geese in association with high blood lead concentration (P < .05). Lead toxicosis induced significant changes in the values of commonly measured hematologic parameters in waterfowl. These changes may be useful indicators of severe lead intoxication during routine laboratory assessment. Changes in clinical chemistry values, although statistically significant, were too inconsistent to serve as indicators of lead toxicosis.

  3. Muted Rhetors and the Mundane: The Case of Ruth Mary Weeks, Rewey Belle Inglis, and W. Wilbur Hatfield

    Science.gov (United States)

    Bordelon, Suzanne

    2012-01-01

    This essay reveals the importance of investigating mundane internal documents, particularly when considering muted rhetors, who may use such texts strategically in an attempt to subvert the status quo. It does so by examining the first and second women presidents of NCTE and their efforts to professionalize the organization and to strengthen the…

  4. Percutaneous untying of a knot in a retained Swan-Ganz catheter

    International Nuclear Information System (INIS)

    Bhatti, Waqar A.; Sinha, Sankar; Rowlands, Peter

    2000-01-01

    A patient was referred to us with a tightly knotted Swan-Ganz catheter. The catheter could not be removed by conventional simple methods. We describe a minimally invasive means of removal of the catheter using an Amplatz gooseneck snare and an angioplasty balloon. This allowed the Catheter to be removed without trauma.

  5. Evaluation of the numerical wave model (SWAN) for wave simulation in the Black Sea

    Science.gov (United States)

    Akpınar, Adem; van Vledder, Gerbrant Ph.; Kömürcü, Murat İhsan; Özger, Mehmet

    2012-12-01

    This study summaries the implementation of the SWAN model forced by the ECMWF ERA Interim dataset reanalyzed 10 m winds over the Black Sea which will be used to study the wind-wave climate and wave energy potential in the region, and its verification. The SWAN model results were compared with directional buoy measurements at three locations along the north and south coasts of the Black Sea, parametric model results based on the JONSWAP growth relations, and the results of previous studies. The SWAN model has been applied in a third generation and non-stationary mode with spherical coordinates. The linear and exponential growth from wind input, depth-induced wave breaking, bottom friction, whitecapping, four-wave (for deep water) and triad-wave (for shallow water) nonlinear interactions have been activated in the simulations. The results of this study indicate that agreement between simulated and observed wave parameters is satisfactory and it is slightly more accurate than the results of the previous studies. However, it still has lower estimates for the maximum values of both wave parameters. These lower estimates are probably due to too low wind speeds in the applied ECMWF wind fields, which is probably caused by orographic effects, and due to the relatively course resolution in time and space of the ECMWF (ERA-Interim) wind fields for the Black Sea.

  6. AUTO-MUTE 2.0: A Portable Framework with Enhanced Capabilities for Predicting Protein Functional Consequences upon Mutation.

    Science.gov (United States)

    Masso, Majid; Vaisman, Iosif I

    2014-01-01

    The AUTO-MUTE 2.0 stand-alone software package includes a collection of programs for predicting functional changes to proteins upon single residue substitutions, developed by combining structure-based features with trained statistical learning models. Three of the predictors evaluate changes to protein stability upon mutation, each complementing a distinct experimental approach. Two additional classifiers are available, one for predicting activity changes due to residue replacements and the other for determining the disease potential of mutations associated with nonsynonymous single nucleotide polymorphisms (nsSNPs) in human proteins. These five command-line driven tools, as well as all the supporting programs, complement those that run our AUTO-MUTE web-based server. Nevertheless, all the codes have been rewritten and substantially altered for the new portable software, and they incorporate several new features based on user feedback. Included among these upgrades is the ability to perform three highly requested tasks: to run "big data" batch jobs; to generate predictions using modified protein data bank (PDB) structures, and unpublished personal models prepared using standard PDB file formatting; and to utilize NMR structure files that contain multiple models.

  7. AUTO-MUTE 2.0: A Portable Framework with Enhanced Capabilities for Predicting Protein Functional Consequences upon Mutation

    Directory of Open Access Journals (Sweden)

    Majid Masso

    2014-01-01

    Full Text Available The AUTO-MUTE 2.0 stand-alone software package includes a collection of programs for predicting functional changes to proteins upon single residue substitutions, developed by combining structure-based features with trained statistical learning models. Three of the predictors evaluate changes to protein stability upon mutation, each complementing a distinct experimental approach. Two additional classifiers are available, one for predicting activity changes due to residue replacements and the other for determining the disease potential of mutations associated with nonsynonymous single nucleotide polymorphisms (nsSNPs in human proteins. These five command-line driven tools, as well as all the supporting programs, complement those that run our AUTO-MUTE web-based server. Nevertheless, all the codes have been rewritten and substantially altered for the new portable software, and they incorporate several new features based on user feedback. Included among these upgrades is the ability to perform three highly requested tasks: to run “big data” batch jobs; to generate predictions using modified protein data bank (PDB structures, and unpublished personal models prepared using standard PDB file formatting; and to utilize NMR structure files that contain multiple models.

  8. SOHO/SWAN OBSERVATIONS OF SHORT-PERIOD SPACECRAFT TARGET COMETS

    International Nuclear Information System (INIS)

    Combi, M. R.; Lee, Y.; Patel, T. S.; Maekinen, J. T. T.; Bertaux, J.-L.; Quemerais, E.

    2011-01-01

    SWAN, the Solar Wind ANisotropies all-sky hydrogen Lyα camera on the Solar and Heliospheric Observatory spacecraft that makes all-sky images of interplanetary neutral hydrogen, has an ongoing campaign to make special observations of comets, both short- and long-period ones, in addition to the serendipitous observations of comets as part of the all-sky monitoring program. We report here on a study of several short-period comets that were detected by SWAN: 21P/Giacobini-Zinner (1998 and 2005 apparitions), 19P/Borrelly (2001 apparition), 81P/Wild 2 (1997 apparition), and 103P/Hartley 2 (1997 apparition). SWAN observes comets over long continuous stretches of their visible apparitions and therefore provides excellent temporal coverage of the water production. For some of the observations we are also able to analyze an entire sequence of images over many days to several weeks/months using our time-resolved model and extract daily average water production rates over continuous periods of several days to months. The short-term (outburst) and long-term behavior can be correlated with other observations. The overall long-term variation is examined in light of seasonal effects seen in the pre- to post-perihelion differences. For 21P/Giacobini-Zinner and 81P/Wild 2 the activity variations over each apparition were more continuously monitored but nonetheless consistent with previous observations. For 19P/Borrelly we found a very steep variation of water production rates, again consistent with some previous observations, and a variation over six months around perihelion that was reasonably consistent with the spin-axis model of Schleicher et al. and the illumination of the main active areas. During the 1997-1998 apparition of 103P/Hartley 2, the target comet of the EPOXI mission (the Deep Impact extended mission), we found a variation with heliocentric distance (∼r -3.6 ) that was almost as steep as 19P/Borrelly and, given the small measured radius near aphelion, this places

  9. Use of mediation to resolve the dispute over low-head hydroelectric development at Swan Lake

    Energy Technology Data Exchange (ETDEWEB)

    O' Connor, D.

    1980-08-01

    In 1978, the Maine Hydroelectric Development Corporation announced that the company planned to renovate five dams on the Goose River near Belfast, Maine to generate electricity. The most important part of the plan involved the use of the first of the dams, at the lower end of Swan Lake, to regulate the flow of water to the downstream dams. For Maine Hydro, management of the Swan Lake dam could make an otherwise marginal proposal lucrative. However, Swan Lake is vitally important to the residents of Swanville. The town was so concerned about the impact of this proposed hydroelectric project that it petitioned the Federal Energy Regulatory Commission (FERC) to deny Maine Hydro's application on the grounds that it would damage the environment, reduce property values and eliminate recreational opportunities for its citizens. This report was written by the mediator of the dispute and represents the views and behavior of the parties as the mediator understood them. It is intended to present the mediator's observations in a way which will inform and assist others who may someday face a difficult situation like the one the Town of Swanville and Maine Hydroelectric Development Corporation faced, and successfully resolved, in the spring and summer of 1979.

  10. Demographic outcomes of diverse migration strategies assessed in a metapopulation of tundra swans.

    Science.gov (United States)

    Ely, Craig R; Meixell, Brandt W

    2016-01-01

    Migration is a prominent aspect of the life history of many avian species, but the demographic consequences of variable migration strategies have only infrequently been investigated, and rarely when using modern technological and analytical methods for assessing survival, movement patterns, and long-term productivity in the context of life history theory. We monitored the fates of 50 satellite-implanted tundra swans (Cygnus columbianus) over 4 years from five disparate breeding areas in Alaska, and used known-fate analyses to estimate monthly survival probability relative to migration distance, breeding area, migratory flyway, breeding status, and age. We specifically tested whether migratory birds face a trade-off, whereby long-distance migrants realize higher survival rates at the cost of lower productivity because of reduced time on breeding areas relative to birds that migrate shorter distances and spend more time on breeding areas. Annual migration distances varied significantly among breeding areas (1020 to 12720 km), and were strongly negatively correlated with time spent on breeding areas (r = -0.986). Estimates of annual survival probability varied by wintering area (Pacific coast, Alaska Peninsula, and Eastern seaboard) and ranged from 0.79 (95%CI: 0.70-0.88) to 1.0, depending on criteria used to discern mortalities from radio failures. We did not find evidence for a linear relationship between migration distance and survival as swans from the breeding areas with the shortest and longest migration distances had the highest survival probabilities. Survival was lower in the first year post-marking than in subsequent years, but there was not support for seasonal differences in survival. Productivity varied among breeding populations and was generally inversely correlated to survival, but not migration distance or time spent on breeding areas. Tundra swans conformed to a major tenet of life history theory, as populations with the highest survival

  11. Black Swan Event Assessment for Fort Leonard Wood, Missouri

    Science.gov (United States)

    2016-03-01

    ER D C/ CE RL S R- 16 -1 Net Zero Planning for Fort Leonard Wood Black Swan Event Assessment for Fort Leonard Wood, Missouri Co ns...search for other technical reports published by ERDC, visit the ERDC online library at http://acwc.sdp.sirsi.net/client/default. Net Zero Planning for...1.8 degrees Celsius knots 0.5144444 meters per second miles (US statute) 1,609.347 meters miles per hour 0.44704 meters per second ERDC/CERL SR

  12. 50 CFR 20.107 - Seasons, limits, and shooting hours for tundra swans.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Seasons, limits, and shooting hours for tundra swans. 20.107 Section 20.107 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR (CONTINUED) TAKING, POSSESSION, TRANSPORTATION, SALE, PURCHASE, BARTER, EXPORTATION, AND IMPORTATION OF WILDLIFE AND PLANTS ...

  13. Advancing gender equality through the Athena SWAN Charter for Women in Science: an exploratory study of women's and men's perceptions.

    Science.gov (United States)

    Ovseiko, Pavel V; Chapple, Alison; Edmunds, Laurel D; Ziebland, Sue

    2017-02-21

    While in the United Kingdom, Ireland, and Australia, higher education and research institutions are widely engaged with the Athena SWAN Charter for Women in Science to advance gender equality, empirical research on this process and its impact is rare. This study combined two data sets (free- text comments from a survey and qualitative interviews) to explore the range of experiences and perceptions of participation in Athena SWAN in medical science departments of a research-intensive university in Oxford, United Kingdom. The study is based on the secondary analysis of data from two projects: 59 respondents to an anonymous online survey (42 women, 17 men) provided relevant free-text comments and, separately, 37 women participated in face-to-face narrative interviews. Free-text survey comments and narrative interviews were analysed thematically using constant comparison. Both women and men said that participation in Athena SWAN had brought about important structural and cultural changes, including increased support for women's careers, greater appreciation of caring responsibilities, and efforts to challenge discrimination and bias. Many said that these positive changes would not have happened without linkage of Athena SWAN to government research funding, while others thought there were unintended consequences. Concerns about the programme design and implementation included a perception that Athena SWAN has limited ability to address longstanding and entrenched power and pay imbalances, persisting lack of work-life balance in academic medicine, questions about the sustainability of positive changes, belief that achieving the award could become an end in itself, resentment about perceived positive discrimination, and perceptions that further structural and cultural changes were needed in the university and wider society. The findings from this study suggest that Athena SWAN has a positive impact in advancing gender equality, but there may be limits to how much it can

  14. Implementing Lumberjacks and Black Swans Into Model-Based Tools to Support Human-Automation Interaction.

    Science.gov (United States)

    Sebok, Angelia; Wickens, Christopher D

    2017-03-01

    The objectives were to (a) implement theoretical perspectives regarding human-automation interaction (HAI) into model-based tools to assist designers in developing systems that support effective performance and (b) conduct validations to assess the ability of the models to predict operator performance. Two key concepts in HAI, the lumberjack analogy and black swan events, have been studied extensively. The lumberjack analogy describes the effects of imperfect automation on operator performance. In routine operations, an increased degree of automation supports performance, but in failure conditions, increased automation results in more significantly impaired performance. Black swans are the rare and unexpected failures of imperfect automation. The lumberjack analogy and black swan concepts have been implemented into three model-based tools that predict operator performance in different systems. These tools include a flight management system, a remotely controlled robotic arm, and an environmental process control system. Each modeling effort included a corresponding validation. In one validation, the software tool was used to compare three flight management system designs, which were ranked in the same order as predicted by subject matter experts. The second validation compared model-predicted operator complacency with empirical performance in the same conditions. The third validation compared model-predicted and empirically determined time to detect and repair faults in four automation conditions. The three model-based tools offer useful ways to predict operator performance in complex systems. The three tools offer ways to predict the effects of different automation designs on operator performance.

  15. Invasive herbivory: resident Canada geese and the decline of wild rice along the tidal Patuxent River

    Science.gov (United States)

    Haramis, G.M.; Kearns, G.D.; Perry, Matthew C.

    2004-01-01

    While concern grows over the increasing numbers of exotic mute swans (Cygnus olor) on the Chesapeake Bay, less attention seems to be given to the highly familiar and native Canada goose (Branta canadensis) which has over time developed unprecedented nonmigratory, or resident, populations. Although nuisance flocks of Canada geese have been well advertised at city parks, athletic fields, and golf courses over the past three decades, recent expansion of populations to an estimated one million birds in the Atlantic Flyway, and to over 100,000 in Maryland, carries a threat of broader ecological consequences.

  16. Recovery of black-necked swans, macrophytes and water quality in a Ramsar wetland of southern Chile: Assessing resilience following sudden anthropogenic disturbances.

    Science.gov (United States)

    Jaramillo, Eduardo; Lagos, Nelson A; Labra, Fabio A; Paredes, Enrique; Acuña, Emilio; Melnick, Daniel; Manzano, Mario; Velásquez, Carlos; Duarte, Cristian

    2018-07-01

    In 2004 migration and mortality for unknown reasons of the herbivorous Black necked swan (Cygnus melancorhyphus (Molina, 1782)) occurred within the Río Cruces wetland (southern Chile), a Ramsar Site and nature sanctuary. Before 2004, this wetland hosted the largest breeding population of this water bird in the Neotropic Realm. The concurrent decrease in the spatial occurrence of the aquatic plant Egeria densa Planch. 1849 - the main food source of swans - was proposed as a cause for swan migration and mortality. Additionally, post-mortem analyses carried out on swans during 2004 showed diminished body weight, high iron loads and histopathological abnormalities in their livers, suggesting iron storage disease. Various hypotheses were postulated to describe those changes; the most plausible related to variations in water quality after a pulp mill located upstream the wetland started to operate in February 2004. Those changes cascaded throughout the stands of E. densa whose remnants had high iron contents in their tissues. Here we present results of a long-term monitoring program of the wetland components, which show that swan population abundance, body weights and histological liver conditions recovered to pre-disturbance levels in 2012. The recovery of E. densa and iron content in plants throughout the wetland, also returned to pre-disturbance levels in the same 8-year time period. These results show the temporal scale over which resilience and natural restoring processes occur in wetland ecosystems of temperate regions such as southern Chile. Copyright © 2018 Elsevier B.V. All rights reserved.

  17. Effects of Deep Water Source-Sink Terms in 3rd generation Wave Model SWAN using different wind data in Black Sea

    Science.gov (United States)

    Kirezci, Cagil; Ozyurt Tarakcioglu, Gulizar

    2016-04-01

    Coastal development in Black Sea has increased in recent years. Therefore, careful monitoring of the storms and verification of numerical tools with reliable data has become important. Previous studies by Kirezci and Ozyurt (2015) investigated extreme events in Black Sea using different wind datasets (NCEP's CFSR and ECMWF's operational datasets) and different numerical tools (SWAN and Wavewatch III). These studies showed that significant effect to results is caused by the deep water source-sink terms (wave growth by wind, deep water dissipation of wave energy (whitecapping) and deep water non-linear wave-wave interactions). According to Timmermans(2015), uncertainty about wind forcing and the process of nonlinear wave-wave interactions are found to be dominant in numerical wave modelling. Therefore, in this study deep water source and sink term solution approaches of 3rd generation numerical tool (SWAN model) are tested, validated and compared using the selected extreme storms in Black Sea. 45 different storms and storm like events observed in Black Sea between years 1994-1999 are selected to use in the models. The storm selection depends on the instrumental wave data (significant wave heights, mean wave period and mean wave direction) obtained in NATO-TU Waves project by the deep water buoy measurements at Hopa, Sinop, Gelendzhik, and wind data (mean and peak wind speeds, storm durations) of the regarding events. 2 different wave growth by wind with the corresponding deep water dissipation terms and 3 different wave -wave interaction terms of SWAN model are used in this study. Wave growth by wind consist of two parts, linear growth which is explained by Cavaleri and Malanotte-Rizzoli(1981),and dominant exponential growth. There are two methods in SWAN model for exponential growth of wave, first one by Snyder et al. (1981), rescaled in terms of friction velocity by Komen et. al (1984) which is derived using driving wind speed at 10m elevation with related drag

  18. Maize stubble as foraging habitat to wintering geese and swans in northern Europe.

    NARCIS (Netherlands)

    Clausen, K.K.; Madsen, J.; Nolet, B.A.; Haugaard, L.

    2018-01-01

    Agricultural crops have become increasingly important foraging habitats to geese and swans in northern Europe, and a recent climate-driven expansion in the area of maize fields has led to a rapid increase in the exploitation of this habitat. However, due to the novelty of maize foraging in this

  19. The C3 Framework: One Year Later - an Interview with Kathy Swan

    Science.gov (United States)

    Social Education, 2014

    2014-01-01

    On September 17, 2013 (Constitution Day), the C3 Framework was released under the title "The College, Career and Civic Life (C3) Framework for Social Studies State Standards: Guidance for Enhancing the Rigor of K-12 Civics, Economics, Geography, and History." The C3 Project Director and lead writer was NCSS member Kathy Swan, who is…

  20. Monitoring the numbers and productivity of Tundra Swans in relation to potential natural gas development in the Mackenzie River Delta, western Canadian Arctic, 2001-2003

    Energy Technology Data Exchange (ETDEWEB)

    Swystun, H.A. [Northern British Columbia Univ., Prince George, BC (Canada); Hines, J.E. [Canadian Wildlife Service, Ottawa, ON (Canada); Dawson, R.D. [Northern British Columbia Univ., Prince George, BC (Canada)

    2005-03-01

    A study was conducted in which tundra swans were used as an indicator species to monitor the environmental change and effects of oil and gas development in the Mackenzie Delta. The objectives were to monitor consistent study plots for tundra swans at development and non development sites and to document nesting success and brood survival. Environmental protection and maintenance of harvestable populations of wildlife are part of land claim agreement for two Aboriginal groups with settled land claims in the Mackenzie Delta. This study also evaluated the possible factors such as habitat and climate, which limit the reproductive success of tundra swans. Their nesting biology was examined along with how they use their habitat. Researchers established 48 plots near exploratory well sites, existing camps, sites of recent seismic exploration and gas fields of known importance. Air surveillance was used to count and observe the swans on a yearly basis, along with their nests and offspring. Plots were located both where development is proposed and where development is not likely to occur. The important spring staging, summer moulting and fall staging areas were identified along with spring migration patterns, behaviour and feeding areas. The 3 proposed drilling sites include Niglingtak (Kendall Island Bird Sanctuary), Taglu, and Parsons Lake. The concerns regarding future development in tundra swan habitat include: (1) areas where drilling and pipeline structures are built may prompt swans to move away from their traditional nesting and feeding areas, (2) human activity will increase due to gas drilling and pipeline construction, which may reduce nesting success, (3) wastes associated with construction sites may attract predators and increase predation on nesting birds, (4) increased air traffic would disturb geese and swan hunting areas, and (5) waterfowl habitat could be lost if spring staging, summer moulting and fall staging areas are not considered when planning

  1. On the Development of an Operational SWAN Model for the Black Sea (poster)

    NARCIS (Netherlands)

    Akpinar, A.; Van Vledder, G.P.

    2013-01-01

    This poster describes the results of some studies performed on the development of an efficient and operational SWAN model for the Black Sea. This model will be used to study the wind-wave climate and wave energy potential in the region and will provide boundary conditions for coastal engineering and

  2. Evaluating the suitability of the SWAN/COSMO-2 model system to simulate short-crested surface waves for a narrow lake with complex bathymetry

    Directory of Open Access Journals (Sweden)

    Michael Graf

    2013-07-01

    Full Text Available The spectral wave model SWAN (Simulating Waves Nearshore was applied to Lake Zurich, a narrow pre-Alpine lake in Switzerland. The aim of the study is to investigate whether the model system consisting of SWAN and the numerical weather prediction model COSMO-2 is a suitable tool for wave forecasts for the pre-Alpine Lake Zurich. SWAN is able to simulate short-crested wind-generated surface waves. The model was forced with a time varying wind field taken from COSMO-2 with hourly outputs. Model simulations were compared with measured wave data at one near-shore site during a frontal passage associated with strong on-shore winds. The overall course of the measured wave height is well captured in the SWAN simulation: the wave amplitude significantly increases during the frontal passage followed by a transient drop in amplitude. The wave pattern on Lake Zurich is quite complex. It strongly depends on the inherent variability of the wind field and on the external forcing due to the surrounding complex topography. The influence of the temporal wind resolution is further studied with two sensitivity experiments. The first one considers a low-pass filtered wind field, based on a 2-h running mean of COSMO-2 output, and the second experiment uses simple synthetic gusts, which are implemented into the SWAN model and take into account short-term fluctuations of wind speed at 1-sec resolution. The wave field significantly differs for the 1-h and 2-h simulations, but is only negligibly affected by the gusts.

  3. Spatial variation in tuber depletion by swans explained by differences in net intake rates

    NARCIS (Netherlands)

    Nolet, BA; Langevoord, O; Bevan, RM; Engelaar, KR; Klaassen, M; Mulder, RJW

    We tested whether the spatial variation in resource depletion by Tundra Swans (Cygnus columbianus) foraging on belowground tubers of sage pondweed (Potnmogeton pectinatus) was caused by differences in net energy intake rates. The variation in giving up densities within the confines of one lake was

  4. Komatiites and nickel sulfide ores of the Black Swan area, Yilgarn Craton, Western Australia. 4. Platinum group element distribution in the ores, and genetic implications

    Science.gov (United States)

    Barnes, Stephen J.

    2004-11-01

    The Black Swan komatiite sequence, in the Eastern Goldfields province of the Archaean Yilgarn Craton in Western Australia, is a body of dominantly olivine-rich cumulates with lesser volumes of spinifex textured rocks, interpreted as a section through an extensive komatiite lava flow field. The sequence hosts a number of nickel sulfide orebodies, including the Silver Swan massive shoot and the Cygnet and Black Swan disseminated orebodies. The massive sulfide orebodies of the Black Swan Succession are pervasively depleted in all platinum group elements (PGEs), particularly Pt and Pd, despite very high Ni contents. This depletion cannot be explained by R-factor variations, which would also require relatively low Ni tenors. The PGE depletion could be explained in part if the ores are enriched in a monosulfide solid solution (MSS) cumulate component, but requires some additional fractional segregation of sulfide melt upstream from the site of deposition. The Silver Swan orebody shows a remarkably consistent vertical zonation in PGE contents, particularly in Ir, Ru, Rh, Os, which increase systematically from very low levels at the stratigraphic base of the sulfide body to maxima corresponding roughly with the top of a lower layer of the orebody rich in silicate inclusions. Platinum shows the opposite trend, but is somewhat modified by remobilisation during talc carbonate alteration. A similar pattern is also observed in the adjacent White Swan orebody. This zonation is interpreted and modelled as the result of fractional crystallisation of MSS from the molten sulfide pool. The strong IPGE depletion towards the base of the orebody may be a consequence of sulfide liquid crystallisation in an inverted thermal gradient, between a thin rapidly cooling upper rind of komatiite lava and a hot substrate.

  5. Water‐Data Report 393556093132501 ELK CREEK NR SUMNER MO, DS ON SWAN LAKE REFUGE-2012

    Data.gov (United States)

    Department of the Interior — LOCATION: Lat. 390 35’ 56.0” N, long. 930 13’ 25” W, at Swan Lake NWR, 23.5 miles southeast of Chillecothe, MO, in Charlton County. Gage is located near abandoned...

  6. Lead poisoning in a Mississippi sandhill crane

    Science.gov (United States)

    Franson, J. Christian; Hereford, Scott G.

    1994-01-01

    Lead poisoning from the ingestion of spent lead shot is well documented in waterfowl (Sanderson and Bellrose 1986) and has been reported in other wetland (Locke et al. 1991, Windingstad et al. 1984) and upland (Hunter and Rosen 1965, Locke and Bagley 1967) avian species. Ingested fishing weights have been implicated in lead poisoning of Trumpeter Swans (Cygnus buccinator) (Blus et al. 1989), Common Loons (Gavia immer) (Locke et al. 1982, Franson and Cliplef 1992, Pokras and Chafe1 1992), Mute Swans (Cygnus olor) (Birkhead 1982), and Sandhill Cranes (Grus canadensis) (Windingstad et al. 1984). The significance of lead poisoning as a mortality factor in avian species other than waterfowl is probably underestimated (Locke and Friend 1992), and any cause of mortality becomes particularly important in species with small population sizes. We report here the first known case of lead poisoning in a Mississippi Sandhill Crane (Grus canadensis pulla), a critically endangered subspecies.

  7. Predicting Effects of Water Regime Changes on Waterbirds: Insights from Staging Swans.

    Science.gov (United States)

    Nolet, Bart A; Gyimesi, Abel; van Krimpen, Roderick R D; de Boer, Willem F; Stillman, Richard A

    2016-01-01

    Predicting the environmental impact of a proposed development is notoriously difficult, especially when future conditions fall outside the current range of conditions. Individual-based approaches have been developed and applied to predict the impact of environmental changes on wintering and staging coastal bird populations. How many birds make use of staging sites is mostly determined by food availability and accessibility, which in the case of many waterbirds in turn is affected by water level. Many water systems are regulated and water levels are maintained at target levels, set by management authorities. We used an individual-based modelling framework (MORPH) to analyse how different target water levels affect the number of migratory Bewick's swans Cygnus columbianus bewickii staging at a shallow freshwater lake (Lauwersmeer, the Netherlands) in autumn. As an emerging property of the model, we found strong non-linear responses of swan usage to changes in water level, with a sudden drop in peak numbers as well as bird-days with a 0.20 m rise above the current target water level. Such strong non-linear responses are probably common and should be taken into account in environmental impact assessments.

  8. IMPROVED LINE DATA FOR THE SWAN SYSTEM 12C13C ISOTOPOLOGUE

    International Nuclear Information System (INIS)

    Ram, Ram S.; Brooke, James S. A.; Bernath, Peter F.; Sneden, Christopher; Lucatello, Sara

    2014-01-01

    We present new, accurate predictions for rotational line positions, excitation energies, and transition probabilities of the 12 C 13 C isotopologue Swan d 3 Π-a 3 Π system 0-0, 0–1, 0–2, 1–0, 1–1, 1–2, 2–0, 2–1, and 2–2 vibrational bands. The line positions and energy levels were predicted through new analyses of published laboratory data for the 12 C 13 C lines. Transition probabilities were derived from recent computations of transition dipole moments and related quantities. The 12 C 13 C line data were combined with similar data for 12 C 2, reported in a companion paper, and applied to produce synthetic spectra of carbon-rich metal-poor stars that have strong C 2 Swan bands. The matches between synthesized and observed spectra were used to estimate band head positions for a few of the 12 C 13 C vibrational bands and to verify that the new computed line data match observed spectra. The much weaker C 2 lines of the bright red giant Arcturus were also synthesized in the band head regions

  9. Predicting Effects of Water Regime Changes on Waterbirds: Insights from Staging Swans.

    Directory of Open Access Journals (Sweden)

    Bart A Nolet

    Full Text Available Predicting the environmental impact of a proposed development is notoriously difficult, especially when future conditions fall outside the current range of conditions. Individual-based approaches have been developed and applied to predict the impact of environmental changes on wintering and staging coastal bird populations. How many birds make use of staging sites is mostly determined by food availability and accessibility, which in the case of many waterbirds in turn is affected by water level. Many water systems are regulated and water levels are maintained at target levels, set by management authorities. We used an individual-based modelling framework (MORPH to analyse how different target water levels affect the number of migratory Bewick's swans Cygnus columbianus bewickii staging at a shallow freshwater lake (Lauwersmeer, the Netherlands in autumn. As an emerging property of the model, we found strong non-linear responses of swan usage to changes in water level, with a sudden drop in peak numbers as well as bird-days with a 0.20 m rise above the current target water level. Such strong non-linear responses are probably common and should be taken into account in environmental impact assessments.

  10. Advancing gender equality through the Athena SWAN Charter for Women in Science: an exploratory study of women?s and men?s perceptions

    OpenAIRE

    Ovseiko, Pavel V.; Chapple, Alison; Edmunds, Laurel D.; Ziebland, Sue

    2017-01-01

    Background While in the United Kingdom, Ireland, and Australia, higher education and research institutions are widely engaged with the Athena SWAN Charter for Women in Science to advance gender equality, empirical research on this process and its impact is rare. This study combined two data sets (free- text comments from a survey and qualitative interviews) to explore the range of experiences and perceptions of participation in Athena SWAN in medical science departments of a research-intensiv...

  11. Water Data Analysis 393937093090901 TURKEY CREEK NR SUMNER MO, FULBRIGHT RD NEAR SWAN LAKE NWR-2013-2016

    Data.gov (United States)

    Department of the Interior — WATER MONITORING STATION ANALYSIS – CALENDAR YEAR 2013 to 2016 SITE NUMBER: 393937093090901 SITE NAME: Turkey Creek nr Sumner MO, Fulbright Rd COOPERATION: Swan Lake...

  12. 76 FR 28024 - Swan Falls Hydroelectric Project, Idaho Power Company; Notice of Teleconference

    Science.gov (United States)

    2011-05-13

    ... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 503-048-ID] Swan Falls Hydroelectric Project, Idaho Power Company; Notice of Teleconference a. Date and Time of Meeting: Tuesday, May 24, 2011 at 10 a.m. (Mountain Time). b. Place: By copy of this notice we are inviting all interested parties to attend a teleconference from...

  13. Widespread exposure to lead affects the body condition of free-living whooper swans Cygnus cygnus wintering in Britain

    International Nuclear Information System (INIS)

    Newth, J.L.; Rees, E.C.; Cromie, R.L.; McDonald, R.A.; Bearhop, S.; Pain, D.J.; Norton, G.J.; Deacon, C.; Hilton, G.M.

    2016-01-01

    Lead poisoning, through the ingestion of spent lead gunshot, is an established cause of morbidity and mortality in waterbirds globally, but the thresholds at which blood levels begin to affect the physiology of birds in the wild are less well known. Here we determine the prevalence of lead exposure in whooper swans and, for the first time, identify the level of blood lead associated with initial reductions in body condition. Blood lead elevated above background levels (i.e. >20 μg dL"−"1) was found in 41.7% (125/300) of swans tested. Blood lead was significantly negatively associated with winter body condition when levels were ≥44 μg dL"−"1 (27/260 = 10%). Our findings indicating that sub-lethal impacts of lead on body condition occur at the lower end of previously established clinical thresholds and that a relatively high proportion of individuals in this population may be affected, reaffirm the importance of reducing contamination of the environment with lead shot. - Highlights: • Elevated blood lead levels of >20 μg dL"−"1 were found in 41.7% of whooper swans. • Blood lead levels of ≥44 μg dL"−"1 were negatively associated with body condition. • Clinical effects were at lower levels than previously described for Anseriformes. • Reduction of lead shot in the environment would reduce the risk of lead exposure. - Blood lead was significantly negatively associated with the body condition of free-living whooper swans in winter when levels were ≥44 μg dL"−"1 (27/260 = 10% of birds were above this threshold).

  14. Health and nutritional status of a perturbed black-necked swan (Cygnus melanocoryphus) population: diet quality.

    Science.gov (United States)

    Norambuena, M Cecilia; Bozinovic, Francisco

    2009-12-01

    The Cayumapu River's black-necked swan population in southern Chile lost its main dietary item, Egeria densa, during an environmental crisis which occurred in 2004 in the Carlos Andwanter Nature Sanctuary. The main goal of this study was to test the effect of diet on the physiologic response to this new ecologic challenge. The results revealed that the new diet of this population was composed primarily of roots and sedimentary microalgae, with chemical and energetic content similar to the diet of the control population. Nevertheless, the mean body mass of the Cayumapu River swans was 25% lower than that of control birds. In addition, the biochemical and hematologic profiles of the study population were indicative of malnutrition and a hyperferremic, hyperphosphatemic, and lymphopenic condition. Liver enzyme activities did not support that the malnutrition was a secondary consequence of liver dysfunction, as is expected under hemochromatosis or environmental toxics exposure.

  15. Genetic consequences of trumpeter swan (Cygnus buccinator) reintroductions

    Science.gov (United States)

    Ransler, F.A.; Quinn, T.W.; Oyler-McCance, S.J.

    2011-01-01

    Relocation programs are often initiated to restore threatened species to previously occupied portions of their range. A primary challenge of restoration efforts is to translocate individuals in a way that prevents loss of genetic diversity and decreases differentiation relative to source populations-a challenge that becomes increasingly difficult when remnant populations of the species are already genetically depauperate. Trumpeter swans were previously extirpated in the entire eastern half of their range. Physical translocations of birds over the last 70 years have restored the species to portions of its historical range. Despite the long history of management, there has been little monitoring of the genetic outcomes of these restoration attempts. We assessed the consequences of this reintroduction program by comparing patterns of genetic variation at 17 microsatellite loci across four restoration flocks (three wild-released, one captive) and their source populations. We found that a wild-released population established from a single source displayed a trend toward reduced genetic diversity relative to and significant genetic differentiation from its source population, though small founder population effects may also explain this pattern. Wild-released flocks restored from multiple populations maintained source levels of genetic variation and lacked significant differentiation from at least one of their sources. Further, the flock originating from a single source revealed significantly lower levels of genetic variation than those established from multiple sources. The distribution of genetic variation in the captive flock was similar to its source. While the case of trumpeter swans provides evidence that restorations from multiple versus single source populations may better preserve natural levels of genetic diversity, more studies are needed to understand the general applicability of this management strategy. ?? 2010 Springer Science+Business Media B.V. (outside

  16. Characterisation of a highly pathogenic H5N1 clade 2.3.2 influenza virus isolated from swans in Shanghai, China.

    Science.gov (United States)

    Zhao, Guo; Zhong, Lei; Lu, Xinlun; Hu, Jiao; Gu, Xiaobing; Kai, Yan; Song, Qingqing; Sun, Qing; Liu, Jinbao; Peng, Daxin; Wang, Xiaoquan; Liu, Xiaowen; Liu, Xiufan

    2012-02-01

    In spring 2009, one strain of H5N1 clade 2.3.2 virus was isolated from wild swans in Shanghai, indicating the importance of the wild swan in the ecology of this highly pathogenic avian influenza virus (HPAIV) in Eastern China. Pathogenicity experiments conducted in this study indicated that the virus was highly pathogenic for chickens but lowly pathogenic for mammalian hosts, as evidenced by reduced infection of mice. The analysis of complete genome sequences and genetic evolution showed that A/Swan/Shanghai/10/09 (SW/SH/09) may be derived from the strain A/silky chicken/Shantou/475/2004 (CK/ST/04), which is homologous to the influenza viruses isolated from chicken, duck, pika, little egret, swan, mandarin duck and bar-headed goose in China Hunan, China Qinghai, Mongolia, Russia, Japan, Korea, Laos and Hong Kong during 2007-2011, indicating that the virus has retro-infected diverse wild birds from chicken, and significant spread of the virus is still ongoing through overlapping migratory flyways. On the basis of the molecular analysis, we also found that there was a deletion of the glycosylation site (NSS) in amino acid 156 of the hemagglutinin (HA) protein when compared with that of the other Clade 2.3.2 viruses isolated between 2007 and 2011. More importantly, the sequence analysis of SW/SH/09 virus displayed the drug-resistant mutations on the matrix protein (M2) and neuraminidase (NA) genes.

  17. The use of a flexible patch leaving rule under exploitative competition: a field test with swans

    NARCIS (Netherlands)

    Nolet, B.A.; Klaassen, R.H.G.; Mooij, W.M.

    2006-01-01

    Learning animals are predicted to use a flexible patch-leaving threshold (PLT) while foraging in a depletable environment under exploitative competition. This prediction was tested in flock-feeding Bewick's swans (Cygnus columbianus bewickii) depleting hidden tubers of fennel pondweed (Potamogeton

  18. Water‐Data Report 393619093074801 YELLOW CREEK NR MENDON MO, HWY CC ON SWAN LAKE NWR-2011

    Data.gov (United States)

    Department of the Interior — LOCATION: Lat. 39036’19”N, long. 9307’48”W near Swan Lake NWR, 23.5 miles southeast of Chillicothe, MO, in Charlton County. Gage is mounted 9 feet off the ground on...

  19. Water‐Data Report 393619093074801 YELLOW CREEK NR MENDON MO, HWY CC ON SWAN LAKE NWR-2012

    Data.gov (United States)

    Department of the Interior — LOCATION: Lat. 39036’19”N, long. 9307’48”W near Swan Lake NWR, 23.5 miles southeast of Chillicothe, MO, in Charlton County. Gage is mounted 9 feet off the ground on...

  20. Water‐Data Report 393619093074801 YELLOW CREEK NR MENDON MO, HWY CC ON SWAN LAKE NWR-2010

    Data.gov (United States)

    Department of the Interior — LOCATION: Lat. 39036’19”N, long. 9307’48”W near Swan Lake NWR, 23.5 miles southeast of Chillicothe, MO, in Charlton County. Gage is mounted 9 feet off the ground on...

  1. Hampered foraging and migratory performance in swans infected with low-pathogenic avian influenza A virus.

    Directory of Open Access Journals (Sweden)

    Jan A van Gils

    Full Text Available It is increasingly acknowledged that migratory birds, notably waterfowl, play a critical role in the maintenance and spread of influenza A viruses. In order to elucidate the epidemiology of influenza A viruses in their natural hosts, a better understanding of the pathological effects in these hosts is required. Here we report on the feeding and migratory performance of wild migratory Bewick's swans (Cygnus columbianus bewickii Yarrell naturally infected with low-pathogenic avian influenza (LPAI A viruses of subtypes H6N2 and H6N8. Using information on geolocation data collected from Global Positioning Systems fitted to neck-collars, we show that infected swans experienced delayed migration, leaving their wintering site more than a month after uninfected animals. This was correlated with infected birds travelling shorter distances and fuelling and feeding at reduced rates. The data suggest that LPAI virus infections in wild migratory birds may have higher clinical and ecological impacts than previously recognised.

  2. Highly pathogenic avian influenza virus (H5N1) isolated from whooper swans, Japan.

    Science.gov (United States)

    Uchida, Yuko; Mase, Masaji; Yoneda, Kumiko; Kimura, Atsumu; Obara, Tsuyoshi; Kumagai, Seikou; Saito, Takehiko; Yamamoto, Yu; Nakamura, Kikuyasu; Tsukamoto, Kenji; Yamaguchi, Shigeo

    2008-09-01

    On April 21, 2008, four whooper swans were found dead at Lake Towada, Akita prefecture, Japan. Highly pathogenic avian influenza virus of the H5N1 subtype was isolated from specimens of the affected birds. The hemagglutinin (HA) gene of the isolate belongs to clade 2.3.2 in the HA phylogenetic tree.

  3. Necrotizing Fasciitis: Diagnostic Challenges in a Mute Bedridden Patient with Atypical Laboratory Parameters

    Directory of Open Access Journals (Sweden)

    Ghan-Shyam Lohiya

    2012-01-01

    Full Text Available A 27-year-old mute bedridden patient required parenteral corticosteroids and antibiotics, and hospitalization for an acute respiratory illness. After 2 days, staff noted a ~0.3 cm blister on the patient’s right heel. Within 19 hours, blistering increased and the foot became partly gangrenous. The patient developed high fever (40.3°C, and leukocytosis (count: 13×109/L; was 6.5×109/L ten days earlier. Necrotizing fasciitis (NF was diagnosed and treated with emergency leg amputation. Histopathology revealed necrosis of fascia, muscle, subcutaneous tissue, and skin. In bedridden patients, corticosteroids may particularly facilitate serious infections, and initial NF blistering may be mistaken for pressure ulcers. Vigilant and frequent whole body monitoring is necessary for all patients incapable of verbalizing their symptoms.

  4. Necrotizing fasciitis: diagnostic challenges in a mute bedridden patient with atypical laboratory parameters.

    Science.gov (United States)

    Lohiya, Ghan-Shyam; Tan-Figueroa, Lilia; Krishna, Vijay; Lohiya, Sunita

    2012-01-01

    A 27-year-old mute bedridden patient required parenteral corticosteroids and antibiotics, and hospitalization for an acute respiratory illness. After 2 days, staff noted a ~0.3 cm blister on the patient's right heel. Within 19 hours, blistering increased and the foot became partly gangrenous. The patient developed high fever (40.3°C), and leukocytosis (count: 13 × 10(9)/L; was 6.5 × 10(9)/L ten days earlier). Necrotizing fasciitis (NF) was diagnosed and treated with emergency leg amputation. Histopathology revealed necrosis of fascia, muscle, subcutaneous tissue, and skin. In bedridden patients, corticosteroids may particularly facilitate serious infections, and initial NF blistering may be mistaken for pressure ulcers. Vigilant and frequent whole body monitoring is necessary for all patients incapable of verbalizing their symptoms.

  5. Burial depth distribution of fennel pondweed tubers (Potamogeton pectinatus) in relation to foraging by Bewick's swans

    NARCIS (Netherlands)

    Hidding, B.; Nolet, B.A.; van Eerden, M.R.; Guillemain, M.; Klaassen, M.R.J.

    2009-01-01

    Deep burial in the sediment of tubers of fennel pondweed (Potamogeton pectinatus) has been explained in terms of avoidance by escape against consumption by Bewick's swans (Cygnus columbianus bewickii) in autumn. We therefore expected changes in foraging pressure to ultimately result in a change in

  6. Gulf of Mexico hurricane wave simulations using SWAN : Bulk formula-based drag coefficient sensitivity for Hurricane Ike

    NARCIS (Netherlands)

    Huang, Y.; Weisberg, R.H.; Zheng, L.; Zijlema, M.

    2013-01-01

    The effects of wind input parameterizations on wave estimations under hurricane conditions are examined using the unstructured grid, third-generation wave model, Simulating WAves Nearshore (SWAN). Experiments using Hurricane Ike wind forcing, which impacted the Gulf of Mexico in 2008, illustrate

  7. Centralized and Distributed Solutions for Fast Muting Adaptation in LTE-Advanced HetNets

    DEFF Research Database (Denmark)

    Soret, Beatriz; Pedersen, Klaus I.

    2015-01-01

    Enhanced Intercell Interference Coordination (eICIC) is known to provide promising performance benefits for LTE-Advanced Heterogeneous Networks. The use of eICIC facilitates more flexible inter-layer load balancing by means of small cell Range Extension (RE) and Almost Blank Subframes (ABS). Even...... though the eICIC configuration (RE and ABS) ideally should be instantaneously adapted to follow the fluctuations of the traffic and the channel conditions over time, previous studies have focused on slow intercell coordination. In this paper, we investigate fast dynamic eICIC solutions for centralized....... Two different fast muting adaptation algorithms are derived, and it is shown how those can be appplied to both the centralized and the distributed architecture. Performance results with bursty traffic show that the fast dynamic adaptation provides significant gains, both in 5%-ile and 50%-ile user...

  8. Pathology of whooper swans (Cygnus cygnus) infected with H5N1 avian influenza virus in Akita, Japan, in 2008.

    Science.gov (United States)

    Ogawa, Shuji; Yamamoto, Yu; Yamada, Manabu; Mase, Masaji; Nakamura, Kikuyasu

    2009-10-01

    Two (1 adult and 1 young bird) of 4 H5N1-highly-pathogenic-avian-influenza (HPAI)-virus-infected whooper swans in Akita, Japan, in 2008 were investigated pathologically. Macroscopically, white spots with hemorrhages were scattered in the pancreas in the adult bird. Histologically, the adult bird had severe necrotizing pancreatitis and mild nonpurulent encephalitis. The young bird had severe nonpurulent encephalitis and nonpurulent enteric ganglionitis, and intestinal venous wall thickening. Virus antigens were detected in the lesions of pancreatitis in the adult bird and of encephalitis in adult and young birds. These findings suggest that the swans died or became moribund due to neurological disorders and necrotizing pancreatitis caused by H5N1 HPAI virus infection.

  9. Nesting ecology of tundra swans on the coastal Yukon-Kuskokwim Delta, Alaska

    Science.gov (United States)

    Babcock, C.A.; Fowler, A.C.; Ely, Craig R.

    2002-01-01

    Nesting ecology of Tundra Swans (Cygnus columbianus columbianus) was studies the Kashunuk River near Old Chevak (61A?26a??N, 165A?27a??W), on the Yukon-Kuskokwim Delta of western Alaska from 1988-2000. Annual variation in snow-melt chronology, nesting phenology, nesting density, clutch size and nest success was examined. The same area (approximately 23 kmA?) was searched each year and nests were found as early as possible in the laying period. Laying initiation dates ranged from 1-27 May and hatch dates from 12 June a?? 4 July among pairs and years of study. The peak arrival of Tundra Swans and the phenology of nest initiation and hatch were highly correlated with the progression of ice and snow melt in spring. Nest density averaged 0.71 kmA? and 89% of nesting pairs hatched at least one egg. Incubation period ranged from 26 to 33 days with a median of 30 days. Clutch size varied significantly among years, driven by a low mean value of 3.4 eggs in 1999. Clutch sizes were generally larger than found in previous investigations on the Yukon-Kuskokwim Delta, and nearly one egg larger than reported for clutches from Alaskaa??s North Slope (=70A?N). There was no indication of reduced clutch size in years of late spring snow melt, although nesting density tended to be lower.

  10. Essential trace (Zn, Cu, Mn and toxic (Cd, Pb, Cr elements in the liver of birds from Eastern Poland

    Directory of Open Access Journals (Sweden)

    Komosa A.

    2012-01-01

    Full Text Available We have focused our study on the concentrations of essential heavy metals (Zn, Cu and Mn and non-essential trace metals (Pb, Cd and Cr in the livers of birds from Eastern Poland. The largest mean amount of Zn - as much as 279 mg/kg dry mass (d.m. - was found in mute swans. However, only in one of the analysed buzzard specimens the concentration of Zn, found to be 664 mg/kg d.m., exceeded the level indicative of poisoning for this element. Birds specializing in catching rodents accumulated Mn in their livers in a very narrow range of concentrations, around 5.0 mg/kg d.m. on average. The range of mean Mn concentrations (around 6.5 mg/kg d.m. was also found to be narrow for piscivorous birds. The highest mean levels of Pb were found in mute swans (2.7 mg/kg d.m., and the highest levels of Cd (2.0 mg/kg d.m. for rooks. Concentrations of total Cr above detection level were found in 22 specimens (53.7%, and concentration values were highest for rooks. Analyses showed that the concentrations of biogenic elements did not exceed the levels indicative of poisoning (except in one specimen. The study demonstrated that lead shots remain a hazard to water ecosystems. Pb, Cd and Cr levels in the livers of omnivorous and piscivorous species indicate the permanent presence of these elements in the environment and may confirm the thesis about the growing role of electronic waste, including metallic e-waste, in the emission of the total amount of contamination with these elements.

  11. WATER PRODUCTION BY COMET 103P/HARTLEY 2 OBSERVED WITH THE SWAN INSTRUMENT ON THE SOHO SPACECRAFT

    International Nuclear Information System (INIS)

    Combi, M. R.; Bertaux, J.-L.; Quemerais, E.; Ferron, S.; Maekinen, J. T. T.

    2011-01-01

    Global water production rates were determined from the Lyα emission of hydrogen around comet 103P/Hartley 2, observed with the SWAN (Solar Wind Anisotropies) all-sky camera on the SOHO spacecraft from 2010 September 14 through December 12. This time period included the November 4 flyby by the EPOXI spacecraft. Water production was three times lower than during the 1997 apparition also measured by SWAN. In 2010, it increased by a factor of ∼2.5 within one day on September 30 with a similar corresponding drop between November 24 and 30. The total surface area of sublimating water within ±20 days of perihelion was ∼0.5 km 2 , about half of the mean cross section of the nucleus. Outside this period it was ∼0.2 km 2 . The peak value was 90%, implying a significant water production by released nucleus icy fragments.

  12. Antigenic, genetic, and pathogenic characterization of H5N1 highly pathogenic avian influenza viruses isolated from dead whooper swans (Cygnus cygnus) found in northern Japan in 2008.

    Science.gov (United States)

    Okamatsu, Masatoshi; Tanaka, Tomohisa; Yamamoto, Naoki; Sakoda, Yoshihiro; Sasaki, Takashi; Tsuda, Yoshimi; Isoda, Norikazu; Kokumai, Norihide; Takada, Ayato; Umemura, Takashi; Kida, Hiroshi

    2010-12-01

    In April and May 2008, whooper swans (Cygnus cygnus) were found dead in Hokkaido in Japan. In this study, an adult whooper swan found dead beside Lake Saroma was pathologically examined and the identified H5N1 influenza virus isolates were genetically and antigenically analyzed. Pathological findings indicate that the swan died of severe congestive edema in the lungs. Phylogenetic analysis of the HA genes of the isolates revealed that they are the progeny viruses of isolates from poultry and wild birds in China, Russia, Korea, and Hong Kong. Antigenic analyses indicated that the viruses are distinguished from the H5N1 viruses isolated from wild birds and poultry before 2007. The chickens vaccinated with A/duck/Hokkaido/Vac-1/2004 (H5N1) survived for 14 days after challenge with A/whooper swan/Hokkaido/1/2008 (H5N1), although a small amount of the challenge virus was recovered from the tissues of the birds. These findings indicate that H5N1 highly pathogenic avian influenza viruses are circulating in wild birds in addition to domestic poultry in Asia and exhibit antigenic variation that may be due to vaccination.

  13. 76 FR 29259 - Swan Lake National Wildlife Refuge, Chariton County, MO; Final Comprehensive Conservation Plan...

    Science.gov (United States)

    2011-05-20

    ...We, the U.S. Fish and Wildlife Service (Service), announce the availability of the Final Comprehensive Conservation Plan (CCP) and Finding of No Significant Impact (FONSI) for the Environmental Assessment (EA) for Swan Lake National Wildlife Refuge (NWR). Goals and objectives in the CCP describe how the agency intends to manage the refuge over the next 15 years.

  14. Bagging grey swans : A supply network approach to identifying and managing low-probability high-impact supply chain events

    NARCIS (Netherlands)

    Rossetti, Christian; Akkermans, Henk; Bhakoo, Vikram; Carnovale, Steven

    Over the past decade practitioners and researchers have become increasingly focused on managing risks in extended supply chains. Whether these risks involve supply disruptions, financial liabilities for a supplier’s actions, or large market shifts; Grey Swan events, defined as unforeseen

  15. [Book review] Ducks, geese and swans of North America

    Science.gov (United States)

    Krapu, Gary L.

    1983-01-01

    This is the 3rd edition of the classic work "The Ducks, Geese and Swans of North America," which was first published in December 1942.  The original edition was authored by Francis C. Kortright with color plates by T. M. Shortt. An authoritative reference on North American waterfowl for many years, the book had become outdated as a result of major advances in the field of waterfowl biology. The need to update the 1st edition culminated in the publication in 1976 of a 2nd edition authored by Frank Bellrose. Readers interested in comparing features of the 1976 edition with other major recent works on North American waterfowl by P. A. Johnsgard and R. S. Palmer should read Weller (1977, Auk 94: 173).

  16. The Black Swan di Darren Aronofsky. Lo specchio come indagine psicanalitica sulla pazzia

    Directory of Open Access Journals (Sweden)

    Francesca Casella

    2014-07-01

    Full Text Available Darren Aronofsky's 'The Black Swan' is certainly one of the most emblematic and controversial movie of the recent years. Considered a masterpiece or panned brutally, echo’s a long line of films that led themselves to a psychoanalytic analysis. In attempt to give a proper interpretation of the imaginary film work, strongly linked to the theme of the double and the mirror, were used two founders of the philosophy of mind: Singmund Freud and Otto Rank.

  17. Tourism today: Between the black swan and the reality of the fiction

    Directory of Open Access Journals (Sweden)

    Clara Inés Sánchez Arciniegas

    2017-07-01

    Full Text Available The present essay begins by adapting the metaphor of Nassim Taleb, The Black Swan to the phenomenon of tourism in order to inquire the effects that terrorism acts have on the world´s tourist behaviour. This article was finished on June 2016 and is consistent with the unpredictability of subsequent events. You won’t find an analysis of statistics based on tourism models or analysis methods; nonetheless it presents a deductive approximation based on news reviews and social network publications that circulate about tourism. On the one hand, the news related to the impacts of terrorist attacks disturb the world at global scale making an impact on tourism destinations and on the other hand, there are cities with a parallel reality, one that shows an idyllic world, with positive and encouraging statistics of tourist visitors, travel promotion and circulation of travel experiences in social networks. Resembling the novel, the fiction of real characters. The sources triangulation, is not conclusive but indicative about the vast information that exists, the elaborated circulation of images and the broad literature of tourism; (some of them showing an interdisciplinary relation between terrorism and tourism however, some of it lacks research and do not contribute to the knowledge of this phenomenon in social and economic aspects, beyond the marketing, a thematic highly privilege by the production of texts. The current swan disturbs, but the reaction of the travel industry is to settle.

  18. A STRUGGLE FOR LOVE OF BELLA SWAN REFLECTED IN NEW MOON MOVIE: AN INDIVIDUAL PSYCHOLOGICAL APPROACH

    Directory of Open Access Journals (Sweden)

    Ayu Riska Lestari

    2012-12-01

    Full Text Available This paper described the struggle for love of Bella Swan reflected in New Moon movie by using Alfred Adler’s individual psychology and analyzed the plot of the movie. It used qualitative research method and the object of this study was a major character named Bella Swan. Primary data sources were the New Moon movie directed by Christopher Weitz and the script of the movie, while secondary data sources were collected from many sources such as dictionary, articles from internet, and books related to this study. Methods of data collecting were observation and library research. The method of data analysis was descriptive analysis. Based on the analysis, It reflected the condition of a person who had a goal and struggle to get it. It concluded that Bella had high struggles to reach her goals. The plot of New Moon movie is complicated and stimulating, therefore it made the story was not flat and boring. By analyzing the plot, the viewers could easily understand the story and the message of the movie and catch up the moral lesson of it.

  19. Dragon-Kings, Black-Swans and Prediction (Invited)

    Science.gov (United States)

    Sornette, D.

    2010-12-01

    Extreme fluctuations or events are often associated with power law statistics. Indeed, it is a popular belief that "wild randomness'' is deeply associated with distributions with power law tails characterized by small exponents. In other words, power law tails are often seen as the epitome of extreme events (the "Black Swan'' story). Here, we document in very different systems that there is life beyond power law tails: power laws can be superseded by "dragon-kings'', monster events that occur beyond (or changing) the power law tail. Dragon-kings reveal hidden mechanisms that are only transiently active and that amplify the normal fluctuations (often described by the power laws of the normal regime). The goal of this lecture is to catalyze the interest of the community of geophysicists across all fields of geosciences so that the "invisible gorilla" fallacy may be avoided. Our own research illustrates that new statistics or representation of data are often necessary to identify dragon-kings, with strategies guided by the underlying mechanisms. Paradoxically, the monsters may be ignored or hidden by the use of inappropriate analysis or statistical tools that amount to cut a mamooth in small pieces, so as to lead to the incorrect belief that only mice exist. In order to stimulate further research, we will document and discuss the dragon-king phenomenon on the statistics of financial losses, economic geography, hydrodynamic turbulence, mechanical ruptures, avalanches in complex heterogeneous media, earthquakes, and epileptic seizures. The special status of dragon-kings open a new research program on their predictability, based on the fact that they belong to a different class of their own and express specific mechanisms amplifying the normal dynamics via positive feedbacks. We will present evidence of these claims for the predictions of material rupture, financial crashes and epileptic seizures. As a bonus, a few remarks will be offered at the end on how the dragon

  20. Statistical Tests Black swans or dragon-kings? A simple test for deviations from the power law★

    Science.gov (United States)

    Janczura, J.; Weron, R.

    2012-05-01

    We develop a simple test for deviations from power law tails. Actually, from the tails of any distribution. We use this test - which is based on the asymptotic properties of the empirical distribution function - to answer the question whether great natural disasters, financial crashes or electricity price spikes should be classified as dragon-kings or `only' as black swans.

  1. The SWAN coupling code: user's guide

    International Nuclear Information System (INIS)

    Litaudon, X.; Moreau, D.

    1988-11-01

    Coupling of slow waves in a plasma near the lower hybrid frequency is well known and linear theory with density step followed by a constant gradient can be used with some confidence. With the aid of the computer code SWAN, which stands for 'Slow Wave Antenna', the following parameters can be numerically calculated: n parallel power spectrum, directivity (weighted by the current drive efficiency), reflection coefficients (amplitude and phase) both before and after the E-plane junctions, scattering matrix at the plasma interface, scattering matrix at the E-plane junctions, maximum electric fields in secondary waveguides and location where it occurs, effect of passive waveguides on each side of the antenna, and the effect of a finite magnetic field in front of the antenna (for homogeneous plasma). This manual gives the basic information on the main assumptions of the coupling theory and on the use and general structure of the code itself. It answers the questions what are the main assumptions of the physical model? how to execute a job? what are the input parameters of the code? and what are the output results and where are they written? (author)

  2. [Swan Song: The Advent of the Psychotic Nucleus].

    Science.gov (United States)

    Zúñiga, Fernando Muñoz

    2012-09-01

    Different forms of artistic expression, such as literature and cinema, constitute an inexhaustible source for the study of mental illness. The use of psychodynamic models may contribute to a better understanding of the spectrum between personality disorders and the psychosis spectrum, thus enriching the phenomenological approach in the psychiatric clinical practice. To examine from psychodynamic standpoints the main character of the American film Black Swan, and the nature of her psychotic symptoms. Reviewing of sources and relevant theoretical currents. Analysis shows the usefulness of a psychodynamically- oriented dimensional model for understanding the so-called psychotic breaks as well as the applicability of psychoanalytic psychosis theories in general psychiatric practice, as they may provide a more flexible clinical approach, closer to the patient's subjective experience. Copyright © 2012 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.

  3. Can sacrificial feeding areas protect aquatic plants from herbivore grazing? Using behavioural ecology to inform wildlife management.

    Directory of Open Access Journals (Sweden)

    Kevin A Wood

    Full Text Available Effective wildlife management is needed for conservation, economic and human well-being objectives. However, traditional population control methods are frequently ineffective, unpopular with stakeholders, may affect non-target species, and can be both expensive and impractical to implement. New methods which address these issues and offer effective wildlife management are required. We used an individual-based model to predict the efficacy of a sacrificial feeding area in preventing grazing damage by mute swans (Cygnus olor to adjacent river vegetation of high conservation and economic value. The accuracy of model predictions was assessed by a comparison with observed field data, whilst prediction robustness was evaluated using a sensitivity analysis. We used repeated simulations to evaluate how the efficacy of the sacrificial feeding area was regulated by (i food quantity, (ii food quality, and (iii the functional response of the forager. Our model gave accurate predictions of aquatic plant biomass, carrying capacity, swan mortality, swan foraging effort, and river use. Our model predicted that increased sacrificial feeding area food quantity and quality would prevent the depletion of aquatic plant biomass by swans. When the functional response for vegetation in the sacrificial feeding area was increased, the food quantity and quality in the sacrificial feeding area required to protect adjacent aquatic plants were reduced. Our study demonstrates how the insights of behavioural ecology can be used to inform wildlife management. The principles that underpin our model predictions are likely to be valid across a range of different resource-consumer interactions, emphasising the generality of our approach to the evaluation of strategies for resolving wildlife management problems.

  4. A Black Swan and Sub-continental Scale Dynamics in Humid, Late-Holocene Broadleaf Forests

    Science.gov (United States)

    Pederson, N.; Dyer, J.; McEwan, R.; Hessl, A. E.; Mock, C. J.; Orwig, D.; Rieder, H. E.; Cook, B. I.

    2012-12-01

    In humid regions with dense broadleaf-dominated forests where gap-dynamics is the prevailing disturbance regime, paleoecological evidence shows regional-scale changes in forest composition associated with climatic change. To investigate the potential for regional events in late-Holocene forests, we use tree-ring data from 76 populations covering 840,000 km2 and 5.3k tree recruitment dates spanning 1.4 million km2 in the eastern US to investigate the occurrence of simultaneous forest dynamics across a humid region. We compare regional forest dynamics with an independent set of annually-resolved tree ring record of hydroclimate to examine whether climate dynamics might drive forest dynamics in this humid region. In forests where light availability is an important limitation for tree recruitment, we document a pulse of tree recruitment during the mid- to late-1600s across the eastern US. This pulse, which can be inferred as large-scale canopy opening, occurred during an era that multiple proxies indicate as extended drought between two intense pluvial. Principal component analysis of the 76 populations indicates a step-change increase in average ring width during the late-1770s resembling a potential canopy accession event over 42,800 km2 of the southeastern US. Growth-release analysis of populations loading strongly on this eigenvector indicates severe canopy disturbance from 1775-1779 that peaked in 1776. The 1776 event follows a period with extended droughts and severe large-scale frost event. We hypothesize these climatic events lead to elevated tree mortality in the late-1770s and canopy accession for understory trees. Superposed epoch analysis reveals that spikes of elevated canopy disturbance from 1685-1850 CE are significantly associated with drought. Extreme value theory statistics indicates the 1776 event lies beyond the 99.9 quantile and nearly 7 sigmas above the 1685-1850 mean rate of disturbance. The time-series of canopy disturbance from 1685-1850 is so

  5. Komatiites and nickel sulfide ores of the Black Swan area, Yilgarn Craton, Western Australia. 2: Geology and genesis of the orebodies

    Science.gov (United States)

    Dowling, S. E.; Barnes, S. J.; Hill, R. E. T.; Hicks, J. D.

    2004-11-01

    The Black Swan Ultramafic Succession hosts a number of magmatic Fe Ni Cu PGE sulfide ore shoots, ranging from high grade massive ore to low grade disseminated sulfides. Of these, the most economically significant is the Silver Swan massive sulfide orebody, associated with the basal contact of the succession. The deposit varies in thickness between 5 and 20 m, reaches a N S strike length of 75 m, extends for at least 1.2 km of vertical plunge and is open at depth. Overlying matrix (net-textured) ore is rare. Inclusions of dacite are abundant within the lower 5 m of the massive sulfide. They range from angular fragments through smooth sinuous and plumose morphologies to fine lace-like intergrowths with the sulfide matrix, and comprise variable proportions of cores of porphyritic dacite and carapaces with skeletal plagioclase phenocrysts. Dynamic crystallisation and kinetic melting textures in the carapaces indicate that the inclusions have been heated to various temperatures, some well above their liquidus temperature. The composition of the inclusions ranges from a perfect match with the immediate footwall dacites to mixtures of dacite with up to 30% komatiite. The consistent thickness of the inclusion-bearing basal layer within the massive sulphide is interpreted as the extent of 3-D physical connectivity between the inclusions and a partially molten underlying hybrid layer. Primary contacts between the Silver Swan massive sulfide orebody and overlying ultramafic rocks are marked by thin rinds containing coarse-grained chevron-textured chromites with skeletal textures. Compositions of these chromites match those from Kambalda, Perseverance and other localities, and are inconsistent with a metamorphic origin. They are interpreted as markers of primary magmatic contacts. The combination of this feature with the general paucity of matrix ore implies that the massive ore accumulated and solidified before the accumulation of the overlying thick sequence of olivine

  6. Testing The ‘Black Swan Effect’ on Croatian Stock Market Between 2000 and 2013

    OpenAIRE

    Radman Peša, Anita; Brajković, Ana

    2015-01-01

    We tested the economic activity and stock exchange of Croatia as a new country of European Union (EU) in order to investigate the ‘Black Swan effect’ from 2000 to 2013. The empirical findings obtained in application of OLS methodology and Chow breaking point test provide evidence and show that resignation of the Croatian ex-Prime Minister did lead country successfully to EU. Also, ‘The Black Swan’ event, being unpredictable and having huge impact on political and economic environm...

  7. Wave hindcast studies using SWAN nested in WAVEWATCH III - comparison with measured nearshore buoy data off Karwar, eastern Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Amrutha, M.M.; SanilKumar, V.; Sandhya, K.G.; Nair, T.M.B; Rathod, J.L.

    Waves in the nearshore waters (~15 m water-depth) of eastern Arabian Sea were simulated using SWAN nested in WAVEWATCH III (WW3) for the year 2014. The sensitivity of the numerical wave model WW3 towards different source term (ST) packages...

  8. Abandoned spaces, mute memories: On marginalized inhabitants in the urban centres of Slovenia

    Directory of Open Access Journals (Sweden)

    Hrobat-Virloget Katja

    2016-01-01

    Full Text Available Article focuses on degraded heritage(s and their meanings for different groups of inhabitants, interpreting it/them through the studies of dominant and silenced memories. Case-studies of chosen Slovenian urban centres illustrate the consequences of drastic population change after the Second World War and of the transformation of power relations after Slovenia’s independence which brought changes in the political-ideological and economic system. As the authors observed, memories and heritage of Italian, German and Yugoslav inhabitants are often mute and silenced within the contemporary Slovenian hegemonic/authorised heritage discourse. Consequences of changes in social relations were also recognised at the micro level in the valorisation of the socialist heritage of industrial plants and military barracks. Today, these places are left to decay as the material reminders of the unwanted (pre-WWII or socialist past or they are transformed into centres of youth culture, creative industries or administrative centres. However, such reinterpretation does not enable their former users to access them and claim them as their own heritage.

  9. Widespread exposure to lead affects the body condition of free-living whooper swans Cygnus cygnus wintering in Britain.

    Science.gov (United States)

    Newth, J L; Rees, E C; Cromie, R L; McDonald, R A; Bearhop, S; Pain, D J; Norton, G J; Deacon, C; Hilton, G M

    2016-02-01

    Lead poisoning, through the ingestion of spent lead gunshot, is an established cause of morbidity and mortality in waterbirds globally, but the thresholds at which blood levels begin to affect the physiology of birds in the wild are less well known. Here we determine the prevalence of lead exposure in whooper swans and, for the first time, identify the level of blood lead associated with initial reductions in body condition. Blood lead elevated above background levels (i.e. >20 μg dL(-1)) was found in 41.7% (125/300) of swans tested. Blood lead was significantly negatively associated with winter body condition when levels were ≥44 μg dL(-1) (27/260 = 10%). Our findings indicating that sub-lethal impacts of lead on body condition occur at the lower end of previously established clinical thresholds and that a relatively high proportion of individuals in this population may be affected, reaffirm the importance of reducing contamination of the environment with lead shot. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. ``Dual Society Ever Precedes through Trevor SWAN & Wassily Leontief''

    Science.gov (United States)

    Maksoed, Wh-

    ``Dual Society'' introduced by E.F. Schumacher are classified as non-stabile society who easy to shakes by politics uncertainties.in Robert J. Barro & X. Sala-i-Martin: ``Convergence''states: `` a key economic issue is whether poor countries or regions tend to grow faster than rich ones''.For growth models from Roy Forbes Herrod & EvseyDomar, three assumptions described by Eduardo Ley are?[U+2639]i). output is proportional to capital,(ii). Investment ex anteequals saving & (iii) saving proportional to output. Underlines Trevor SWAN, developing countries differ significantly among themselves. Economic growth models comprises Herrod-Domar growth model, Solow growth model & endogenous growth model.Further, for five stages of economic groeth from Rostov of Leontief technology, ever retrieves the Jens Beckert:''Institutional Isomorphism revisited: Convergence & Divergence in Institutional Change''instead Frumkin's ``Institutional Isomorphism & Public Sector Organizations''. Acknowledgment devotes to theLates HE. Mr. BrigadierGeneral-TNI[rtd].Prof. Ir. HANDOJO.

  11. Non-adaptive territory selection by a bird with exceptionally long parental care

    Directory of Open Access Journals (Sweden)

    Radosław Włodarczyk

    2016-03-01

    Full Text Available High-quality territories are expected to provide greater fitness return for breeding individuals and, thus, are likely to have higher long-term occupation rate in comparison to low-quality territories. However, if environmental and ecological cues used for territory selection cannot reliably predict true territory quality, a mismatch between preferences and fitness may occur. We suggest that this kind of non-adaptive territory selection is more likely in species with long reproductive cycles, as a long time interval between territory establishment and young fledgling should reduce predictability of conditions during the critical stages of brood care. In this study, we investigated adaptiveness of territory selection in a migratory bird with exceptionally long parental care, the mute swan Cygnus olor, which requires over four months to complete the entire reproductive cycle from egg laying to young fledging. For this purpose, we collected information on the long-term (10–19 years occupancy of 222 swan breeding territories and correlated it with reproductive performance (n = 1,345 breeding attempts and body condition of breeding adults. We found that long-term occupancy positively correlated with the timing of breeding, suggesting that individuals settled earlier in the attractive, frequently occupied territories. By contrast, we found no relationship between territory occupancy and reproductive output (hatching and fledging success or adult body condition. The results indicate that at the time of territory selection swans might not be able to reliably assess territory quality, likely due to: (1 exceptionally long period of parental care, which reduces temporal correlation between the conditions at the time of territory selection and conditions during chick rearing; and (2 unpredictability of human-related activities that had a major impact on reproductive output of swan pairs in our population.

  12. Implications for stress changes along the Motagua fault and other nearby faults using GPS and seismic constraints on the M=7.3 2009 Swan Islands earthquake

    Science.gov (United States)

    Graham, S. E.; Rodriguez, M.; Rogers, R. D.; Strauch, W.; Hernandez, D.; Demets, C.

    2010-12-01

    The May 28, 2009 M=7.3 Swan Islands earthquake off the north coast of Honduras caused significant damage in the northern part of the country, including seven deaths. This event, the largest in the region for several decades, ruptured the offshore continuation of the Motagua-Polochic fault system, whose 1976 earthquake (located several hundred kilometers to the southwest of the 2009 epicenter) caused more than 23,000 deaths in Central America and left homeless 20% of Guatemala’s population. We use elastic half-space modeling of coseismic offsets measured at 39 GPS stations in Honduras, El Salvador, and Guatemala to better understand the slip source of the recent Swan Islands earthquake. Measured offsets range from .32 meters at a campaign site near the Motagua fault in northern Honduras to 4 millimeters at five continuous sites in El Salvador. Coulomb stress calculations based on the estimated distribution of coseismic slip will be presented and compared to earthquake focal mechanisms and aftershock locations determined from a portable seismic network that was installed in northern Honduras after the main shock. Implications of the Swan Islands rupture for the seismically hazardous Motagua-Polochic fault system will be described.

  13. Hampered performance of migratory swans: intra- and inter-seasonal effects of avian influenza virus.

    Science.gov (United States)

    Hoye, Bethany J; Munster, Vincent J; Huig, Naomi; de Vries, Peter; Oosterbeek, Kees; Tijsen, Wim; Klaassen, Marcel; Fouchier, Ron A M; van Gils, Jan A

    2016-08-01

    The extent to which animal migrations shape parasite transmission networks is critically dependent on a migrant's ability to tolerate infection and migrate successfully. Yet, sub-lethal effects of parasites can be intensified through periods of increased physiological stress. Long-distance migrants may, therefore, be especially susceptible to negative effects of parasitic infection. Although a handful of studies have investigated the short-term, transmission-relevant behaviors of wild birds infected with low-pathogenic avian influenza viruses (LPAIV), the ecological consequences of LPAIV for the hosts themselves remain largely unknown. Here, we assessed the potential effects of naturally-acquired LPAIV infections in Bewick's swans, a long-distance migratory species that experiences relatively low incidence of LPAIV infection during early winter. We monitored both foraging and movement behavior in the winter of infection, as well as subsequent breeding behavior and inter-annual resighting probability over 3 years. Incorporating data on infection history we hypothesized that any effects would be most apparent in naïve individuals experiencing their first LPAIV infection. Indeed, significant effects of infection were only seen in birds that were infected but lacked antibodies indicative of prior infection. Swans that were infected but had survived a previous infection were indistinguishable from uninfected birds in each of the ecological performance metrics. Despite showing reduced foraging rates, individuals in the naïve-infected category had similar accumulated body stores to re-infected and uninfected individuals prior to departure on spring migration, possibly as a result of having higher scaled mass at the time of infection. And yet individuals in the naïve-infected category were unlikely to be resighted 1 year after infection, with 6 out of 7 individuals that never resighted again compared to 20 out of 63 uninfected individuals and 5 out of 12 individuals in

  14. Host behaviour and physiology underpin individual variation in avian influenza virus infection in migratory Bewick's swans.

    Science.gov (United States)

    Hoye, Bethany J; Fouchier, Ron A M; Klaassen, Marcel

    2012-02-07

    Individual variation in infection modulates both the dynamics of pathogens and their impact on host populations. It is therefore crucial to identify differential patterns of infection and understand the mechanisms responsible. Yet our understanding of infection heterogeneity in wildlife is limited, even for important zoonotic host-pathogen systems, owing to the intractability of host status prior to infection. Using novel applications of stable isotope ecology and eco-immunology, we distinguish antecedent behavioural and physiological traits associated with avian influenza virus (AIV) infection in free-living Bewick's swans (Cygnus columbianus bewickii). Swans infected with AIV exhibited higher serum δ13C (-25.3±0.4) than their non-infected counterparts (-26.3±0.2). Thus, individuals preferentially foraging in aquatic rather than terrestrial habitats experienced a higher risk of infection, suggesting that the abiotic requirements of AIV give rise to heterogeneity in pathogen exposure. Juveniles were more likely to be infected (30.8% compared with 11.3% for adults), shed approximately 15-fold higher quantity of virus and exhibited a lower specific immune response than adults. Together, these results demonstrate the potential for heterogeneity in infection to have a profound influence on the dynamics of pathogens, with concomitant impacts on host habitat selection and fitness.

  15. Synthetic profile analysis of the observed (0,0) Swan band of Comet Halley

    International Nuclear Information System (INIS)

    Krishna swamy, K.S.

    1991-01-01

    The time-dependent rotational population distribution for the (0,0) band of the Swan system was carried out. These population distributions are used to calculate the synthetic spectra over the wavelength region 5165-5132 A for comparing with the excellent spectra of Lambert et al. (1990) for Comet Halley. The synthetic spectra for the rotational population distribution corresponding to a time interval of about 8000 sec gives a good fit to the observed spectra over the whole special region. This seems to indicate that the level population does not appear to have reached the steady state values. 16 refs

  16. Treatment of giant pulmonary interstitial emphysema by ipsilateral bronchial occlusion with a Swan-Ganz catheter

    International Nuclear Information System (INIS)

    Rastogi, Shantanu; Gupta, Archana; Wung, Jen-Tien; Berdon, Walter E.

    2007-01-01

    Unilateral giant pulmonary interstitial emphysema (PIE) can be seen as a complication of chronic ventilation in extremely low-birth-weight babies. Many can be managed by conventional pulmonary care which includes positioning, suctioning, chest physiotherapy, gentle conventional ventilation and high-frequency ventilation. Some may need invasive procedures such as lung puncture, pleurotomies and excisional surgery. This is the group in which single-lung ventilation may be beneficial and circumvent the need for an invasive procedure. We describe the technique of single-lung ventilation using a Swan-Ganz catheter to block the main stem bronchus on the diseased side in air-leak syndromes. A retrospective chart review was done on 17 newborns undergoing single-lung ventilation using this technique at the Children's Hospital of New York, Columbia University, from 1986 to 2000. The technique was successful in the management of severe, neonatal unilateral lung disease not responsive to conventional modes of therapy in all but two neonates as seen by a significant improvement in pH and a decrease in PaCO 2 levels. In one neonate malpositioning of the Swan-Ganz catheter balloon could have contributed to the development of pneumothorax. The described technique of single-lung ventilation provides a safe, minimally invasive and economically feasible method of management of unilateral giant PIE in newborns not responsive to conventional modes of therapy with minimal complications. (orig.)

  17. Treatment of giant pulmonary interstitial emphysema by ipsilateral bronchial occlusion with a Swan-Ganz catheter

    Energy Technology Data Exchange (ETDEWEB)

    Rastogi, Shantanu [College of Physicians and Surgeons, Columbia University, Division of Neonatology, Department of Pediatrics, The Children' s Hospital of New York, New York, NY (United States); Maimonides Medical Center, Department of Pediatrics, Brooklyn, NY (United States); Gupta, Archana; Wung, Jen-Tien [College of Physicians and Surgeons, Columbia University, Division of Neonatology, Department of Pediatrics, The Children' s Hospital of New York, New York, NY (United States); Berdon, Walter E. [College of Physicians and Surgeons, Columbia University, Pediatric Radiology, The Children' s Hospital of New York, New York, NY (United States)

    2007-11-15

    Unilateral giant pulmonary interstitial emphysema (PIE) can be seen as a complication of chronic ventilation in extremely low-birth-weight babies. Many can be managed by conventional pulmonary care which includes positioning, suctioning, chest physiotherapy, gentle conventional ventilation and high-frequency ventilation. Some may need invasive procedures such as lung puncture, pleurotomies and excisional surgery. This is the group in which single-lung ventilation may be beneficial and circumvent the need for an invasive procedure. We describe the technique of single-lung ventilation using a Swan-Ganz catheter to block the main stem bronchus on the diseased side in air-leak syndromes. A retrospective chart review was done on 17 newborns undergoing single-lung ventilation using this technique at the Children's Hospital of New York, Columbia University, from 1986 to 2000. The technique was successful in the management of severe, neonatal unilateral lung disease not responsive to conventional modes of therapy in all but two neonates as seen by a significant improvement in pH and a decrease in PaCO{sub 2} levels. In one neonate malpositioning of the Swan-Ganz catheter balloon could have contributed to the development of pneumothorax. The described technique of single-lung ventilation provides a safe, minimally invasive and economically feasible method of management of unilateral giant PIE in newborns not responsive to conventional modes of therapy with minimal complications. (orig.)

  18. Ring Theory

    CERN Document Server

    Jara, Pascual; Torrecillas, Blas

    1988-01-01

    The papers in this proceedings volume are selected research papers in different areas of ring theory, including graded rings, differential operator rings, K-theory of noetherian rings, torsion theory, regular rings, cohomology of algebras, local cohomology of noncommutative rings. The book will be important for mathematicians active in research in ring theory.

  19. Komatiites and nickel sulfide ores of the Black Swan area, Yilgarn Craton, Western Australia. 3: Komatiite geochemistry, and implications for ore forming processes

    Science.gov (United States)

    Barnes, Stephen J.; Hill, Robin E. T.; Evans, Noreen J.

    2004-11-01

    The Black Swan komatiite sequence is a package of dominantly olivine-rich cumulates with lesser volumes of spinifex textured rocks, interpreted as a section through an extensive komatiite lava flow field. The sequence hosts a number of nickel sulfide orebodies, including the Silver Swan massive shoot and the Cygnet and Black Swan disseminated orebodies. A large body of whole rock analyses on komatiitic rocks from the Black Swan area has been filtered for metasomatic effects. With the exception of mobile elements such as Ca and alkalis, most samples retain residual igneous geochemistry, and can be modelled predominantly by fractionation and accumulation of olivine. Whole rock MgO FeO relationships imply a relatively restricted range of olivine compositions, more primitive than the olivine which would have been in equilibrium with the transporting komatiite lavas, and together with textural data indicate that much of the cumulus olivine in the sequence was transported. Flow top compositions show evidence for chromite saturation, but the cumulates are deficient in accumulated chromite. Chromite compositions are typical of those found in compound flow-facies komatiites, and are distinct from those in komatiitic dunite bodies. Incompatible trace element abundances show three superimposed influences: control by the relative proportion of olivine to liquid; a signature of crustal contamination and an overprint of metasomatic introduction of LREE, Zr and Th. This overprint is most evident in cumulates, and relatively insignificant in the spinifex rocks. Platinum and palladium behaved as incompatible elements and are negatively correlated with MgO. They show no evidence for wholesale depletion due to sulfide extraction, which was evidently restricted to specific lava tubes or pathways. The lack of correspondence between PGE depletion and contamination by siliceous material implies that contamination alone is insufficient to generate S-saturation and ore formation in the

  20. Swan Queen, shipping, and boundary regulation in fandom

    Directory of Open Access Journals (Sweden)

    Victoria M. Gonzalez

    2016-09-01

    Full Text Available There are a number of fan activities and practices that are subject to regulation. The mechanisms of regulation in shipping, however, are not always clear. Shipping, the fan activity of romantically pairing two fictional characters, has become a popular and contentious facet of fan interaction. The case that will be examined in this article is that of the Swan Queen ship, which pairs two female characters from Once Upon a Time (2011–. The lengths that fans have gone to support and promote this ship led to rather intense discussion and infighting among members of the Once Upon a Time fandom. I utilize comments and posts made on Tumblr to examine the mechanisms that dictate inclusion and exclusion in shipper communities. In doing so, I hope to identify the kinds of shipper activities that are subject to regulation and the kinds of boundaries that this regulation establishes. Shipping is dictated not only by fans' imaginations but also by boundaries that are performed and regulated on digital forums.

  1. Fragments on black swan: money, credit and finance in The Arcades Project of Walter Benjamin

    OpenAIRE

    Estrada, Fernando

    2010-01-01

    The main objective of this paper is to present a reading of The Arcades Project by Walter Benjamin in the context of the financial crisis, in particular, reflect from a few fragments of Benjamin's work appear to lie around a Black Swan. The recovery of the fragments of The Arcades seems appropriate at a time when the financial crisis should be taught as a deeper crisis. Walter Benjamin is placed beyond its time, with a powerful sense of observation worthy of emulation analytical.

  2. Proceedings – Mathematical Sciences | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    In this article we give a bound on the number of generators of a finitely generated projective module of constant rank over a commutative Noetherian ring in terms of the rank of the module and the dimension of the ring. Under certain conditions we provide an improvement to the Forster–Swan bound in case of finitely ...

  3. Report of the eRHIC Ring-Ring Working Group

    Energy Technology Data Exchange (ETDEWEB)

    Aschenauer, E. C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Berg, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Blaskiewicz, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Brennan, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Fedotov, A. [Brookhaven National Lab. (BNL), Upton, NY (United States); Fischer, W. [Brookhaven National Lab. (BNL), Upton, NY (United States); Litvinenko, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Montag, C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Palmer, R. [Brookhaven National Lab. (BNL), Upton, NY (United States); Parker, B. [Brookhaven National Lab. (BNL), Upton, NY (United States); Peggs, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ptitsyn, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ranjbar, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Tepikian, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Trbojevic, D. [Brookhaven National Lab. (BNL), Upton, NY (United States); Willeke, F. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-10-13

    This report evaluates the ring-ring option for eRHIC as a lower risk alternative to the linac-ring option. The reduced risk goes along with a reduced initial luminosity performance. However, a luminosity upgrade path is kept open. This upgrade path consists of two branches, with the ultimate upgrade being either a ring-ring or a linac-ring scheme. The linac-ring upgrade could be almost identical to the proposed linac-ring scheme, which is based on an ERL in the RHIC tunnel. This linac-ring version has been studied in great detail over the past ten years, and its significant risks are known. On the other hand, no detailed work on an ultimate performance ring-ring scenario has been performed yet, other than the development of a consistent parameter set. Pursuing the ring-ring upgrade path introduces high risks and requires significant design work that is beyond the scope of this report.

  4. Joseph Swan (1791-1874): pioneer of research on peripheral nerves.

    Science.gov (United States)

    Barton, N J; Smith, B D

    2008-06-01

    Joseph Swan was born in 1791 and appointed surgeon to Lincoln County Hospital in 1814. In addition to his clinical work, he carried out what were probably the first animal experiments on nerve injuries. These were mostly on rabbits, in which the sciatic nerves were partly or wholly divided, had a section excised, or were ligated. He found that regeneration could occur, even after neurectomy. He reported these results, together with his experience in human patients and the effects of neurectomy in a horse, in an essay of 1819, which won the Jacksonian Prize of the Royal College of Surgeons of England and is still preserved there. In 1827 he moved to London, where he devoted himself mainly to dissections of the nervous system and was active in the College. He retired to Filey in Yorkshire, where he died in 1874.

  5. Longer guts and higher food quality increase energy intake in migratory swans.

    Science.gov (United States)

    van Gils, Jan A; Beekman, Jan H; Coehoorn, Pieter; Corporaal, Els; Dekkers, Ten; Klaassen, Marcel; van Kraaij, Rik; de Leeuw, Rinze; de Vries, Peter P

    2008-11-01

    1. Within the broad field of optimal foraging, it is increasingly acknowledged that animals often face digestive constraints rather than constraints on rates of food collection. This therefore calls for a formalization of how animals could optimize food absorption rates. 2. Here we generate predictions from a simple graphical optimal digestion model for foragers that aim to maximize their (true) metabolizable food intake over total time (i.e. including nonforaging bouts) under a digestive constraint. 3. The model predicts that such foragers should maintain a constant food retention time, even if gut length or food quality changes. For phenotypically flexible foragers, which are able to change the size of their digestive machinery, this means that an increase in gut length should go hand in hand with an increase in gross intake rate. It also means that better quality food should be digested more efficiently. 4. These latter two predictions are tested in a large avian long-distance migrant, the Bewick's swan (Cygnus columbianus bewickii), feeding on grasslands in its Dutch wintering quarters. 5. Throughout winter, free-ranging Bewick's swans, growing a longer gut and experiencing improved food quality, increased their gross intake rate (i.e. bite rate) and showed a higher digestive efficiency. These responses were in accordance with the model and suggest maintenance of a constant food retention time. 6. These changes doubled the birds' absorption rate. Had only food quality changed (and not gut length), then absorption rate would have increased by only 67%; absorption rate would have increased by only 17% had only gut length changed (and not food quality). 7. The prediction that gross intake rate should go up with gut length parallels the mechanism included in some proximate models of foraging that feeding motivation scales inversely to gut fullness. We plea for a tighter integration between ultimate and proximate foraging models.

  6. Introduction to nickel sulfide orebodies and komatiites of the Black Swan area, Yilgarn Craton, Western Australia

    Science.gov (United States)

    Barnes, S. J.

    2004-11-01

    The Black Swan district, 70 km north east of Kalgoorlie in the Archaean Yilgarn Craton of Western Australia, hosts massive and disseminated nickel sulfide orebodies associated with komatiites. The host rocks and ores preserve some remarkable primary igneous features, which provide important clues as to the origin of komatiite-hosted nickel ores. The series of papers that follow report an extremely detailed study of the petrology, volcanology and geochemistry of these unusually well-preserved orebodies and their host rocks.

  7. [Growth adaptability of Zostera marina at different habitats of the Swan Lake in Rongcheng, China].

    Science.gov (United States)

    Guo, Mei Yu; Li, Wen Tao; Yang, Xiao Long; Zhang, Xiu Mei; Liu, Jian Ying; Li, Chang Jun

    2017-05-18

    Eelgrass (Zostera marina), a seagrass species widely distributed in the coastal regions of northern hemisphere, has suffered with a great decline due to a variety of anthropogenic and environmental stresses. In order to examine the adaptability of eelgrass to different environmental stresses, studies on the morphology and reproductive capacity of eelgrass had been carried out monthly from November 2014 to October 2015 at four different habitats of the Swan Lake, including patch area inintertidal area and subtidal area, eelgrass meadow edge, and eelgrass meadow area. The results showed significant spatio-temporal variations in the morphological parameters and branch frequency of eelgrass shoots at different habitats of the Swan Lake. The highest values of leaf length, leaf width, aboveground/belowground biomass, and internode length/diameter were observed in the meadow area, i.e., 78.54 cm, 7.93 mm, 7.03 and 3.88, respectively, while the highest branch frequency was observed in the meadow edge (88.4%). The plasticity index for aboveground/belowground biomass was higher (ranging from 0.77 to 0.92) at the four habitats, but those for the leaf width was slightly lower (ranging from 0.41 to 0.64). The number of spathes in each shoot showed no significant difference at different habitats, whereas the number of spathes per unit area was significantly different. Clonal reproduction was more dominant in meadow area than in the patch area where human disturbance was high.

  8. THE GALACTIC R CORONAE BOREALIS STARS: THE C2 SWAN BANDS, THE CARBON PROBLEM, AND THE 12C/13C RATIO

    International Nuclear Information System (INIS)

    Hema, B. P.; Pandey, Gajendra; Lambert, David L.

    2012-01-01

    Observed spectra of R Coronae Borealis (RCB) and hydrogen-deficient carbon (HdC) stars are analyzed by synthesizing the C 2 Swan bands (1, 0), (0, 0), and (0, 1) using our detailed line list and the Uppsala model atmospheres. The (0, 1) and (0, 0) C 2 bands are used to derive the 12 C abundance, and the (1, 0) 12 C 13 C band to determine the 12 C/ 13 C ratios. The carbon abundance derived from the C 2 Swan bands is about the same for the adopted models constructed with different carbon abundances over the range 8.5 (C/He = 0.1%) to 10.5 (C/He = 10%). Carbon abundances derived from C I lines are about a factor of four lower than the carbon abundance of the adopted model atmosphere over the same C/He interval, as reported by Asplund et al., who dubbed the mismatch between adopted and derived C abundance as the 'carbon problem'. In principle, the carbon abundances obtained from C 2 Swan bands and that assumed for the model atmosphere can be equated for a particular choice of C/He that varies from star to star. Then, the carbon problem for C 2 bands is eliminated. However, such C/He ratios are in general less than those of the extreme helium stars, the seemingly natural relatives to the RCB and HdC stars. A more likely solution to the C 2 carbon problem may lie in a modification of the model atmosphere's temperature structure. The derived carbon abundances and the 12 C/ 13 C ratios are discussed in light of the double degenerate and the final flash scenarios.

  9. Detailed review and analysis of complex radiotherapy clinical trial planning data: Evaluation and initial experience with the SWAN software system

    International Nuclear Information System (INIS)

    Ebert, Martin A.; Haworth, Annette; Kearvell, Rachel; Hooton, Ben; Coleman, Rhonda; Spry, Nigel; Bydder, Sean; Joseph, David

    2008-01-01

    Aim: Contemporary radiotherapy clinical trials typically require complex three-dimensional (3D) treatment planning. This produces large amounts of data relating technique and dose delivery for correlation with patient outcomes. Assessment of the quality of this information is required to ensure protocol compliance, to quantify the variation in treatments given to patients and to enhance the power of studies to determine correlates of patient outcomes. Materials and methods: A software system ('SWAN') was developed to facilitate the objective analysis, quality-assurance and review of digital treatment planning data from multi-centre radiotherapy trials. The utility of this system was assessed on the basis of its functionality and our experience of its use in the context of multi-centre clinical trials and trials-support activities. Results: The SWAN system has been shown to have the functionality required for use in several multi-centre trials, including automated review and archive processes. Approximately 800 treatment plans from over 30 participating institutions have so far been assessed with the system for several treatment planning scenarios. To illustrate this we include a description of the use of the system for a large-recruitment prostate radiotherapy trial being undertaken in Australasia, including examples of how the review process has changed clinical practice. Conclusion: The successful implementation of SWAN has been demonstrated in a number of clinical trials. The software provides an opportunity for comprehensive review of treatment parameters that could impact on clinical outcomes and trial results. Such quality-assurance (QA) has previously been difficult or impossible to achieve, particularly for a clinical trial involving large numbers of patients. Such reviews have highlighted inconsistencies in clinical practice that have since been addressed through feedback from the review process. The process of data collection and review should be

  10. Identification of a novel bile acid in swans, tree ducks, and geese: 3alpha,7alpha,15alpha-trihydroxy-5beta-cholan-24-oic acid.

    Science.gov (United States)

    Kakiyama, Genta; Iida, Takashi; Goto, Takaaki; Mano, Nariyasu; Goto, Junichi; Nambara, Toshio; Hagey, Lee R; Schteingart, Claudio D; Hofmann, Alan F

    2006-07-01

    By HPLC, a taurine-conjugated bile acid with a retention time different from that of taurocholate was found to be present in the bile of the black-necked swan, Cygnus melanocoryphus. The bile acid was isolated and its structure, established by (1)H and (13)C NMR and mass spectrometry, was that of the taurine N-acyl amidate of 3alpha,7alpha,15alpha-trihydroxy-5beta-cholan-24-oic acid. The compound was shown to have chromatographic and spectroscopic properties that were identical to those of the taurine conjugate of authentic 3alpha,7alpha,15alpha-trihydroxy-5beta-cholan-24-oic acid, previously synthesized by us from ursodeoxycholic acid. By HPLC, the taurine conjugate of 3alpha,7alpha,15alpha-trihydroxy-5beta-cholan-24-oic acid was found to be present in 6 of 6 species in the subfamily Dendrocygninae (tree ducks) and in 10 of 13 species in the subfamily Anserinae (swans and geese) but not in other subfamilies in the Anatidae family. It was also not present in species from the other two families of the order Anseriformes. 3alpha,7alpha,15alpha-Trihydroxy-5beta-cholan-24-oic acid is a new primary bile acid that is present in the biliary bile acids of swans, tree ducks, and geese and may be termed 15alpha-hydroxy-chenodeoxycholic acid.

  11. Cumulative Effects of Micro-Hydro Development on the Fisheries of the Swan River Drainage, Montana, First Annual Progress Report (Covering Field Season July-November 1982).

    Energy Technology Data Exchange (ETDEWEB)

    Leathe, Stephen A.; Graham, Patrick J.

    1984-03-01

    This fisheries study is to determine the potential cumulative biological and economic effects of 20 small or micro-hydro-electric facilities (less than 5 megawatts) proposed to be constructed on tributaries to the Swan River, a 1738 square kilometer (671 square mile) drainage located in northwestern Montana. The study addresses portions of measure 1204 (b) (2) of the Norwthwest Power Planning Council's Columbia River Basin Fish and Wildlife Program. Aerial pre-surveys conducted during 1982 identified 102 stream reaches that may support fish populations in the Swan drainage between Swan and Lindbergh lakes. These reaches were located in 49 tributary streams and constituted 416 kilometers (258 miles) of potential fish habitat. Construction of all proposed small hydro projects would divert water from 54 kilometers (34 miles) or about 13 percent of the tributary system. Only two of the 20 proposed hydro sites did not support trout populations and most were populated by migratory bull trout and westslope cutthroat trout. Potential cumulative habitat losses that could result from dewatering of all proposed project areas were predicted using a stream reach classification scheme involving stream gradient, drainage ara, and fish population data. Preliminary results of this worst case analysis indicate that 23, 19 and 6 percent of the high quality rearing habitat for cutthroat, bull, and brook trout respectively would be lost.

  12. ASSOCIATIVE RINGS SOLVED AS LIE RINGS

    Directory of Open Access Journals (Sweden)

    M. B. Smirnov

    2011-01-01

    Full Text Available The paper has proved that an associative ring which is solvable of a n- class as a Lie ring has a nilpotent ideal of the nilpotent class not more than 3×10n–2  and a corresponding quotient ring satisfies an identity [[x1, x2, [x3, x4

  13. Changing distribution and abundance of Swan Goose Anser cygnoides in the Yangtze River floodplain: the likely loss of a very important wintering site

    NARCIS (Netherlands)

    Zhang, Y.; Cao, L.; Barter, M.; Fox, A.D.; Zhao, M.; Meng, F.; Shi, H.; Jiang, Y.; Zhu, W.

    2011-01-01

    Virtually the entire population of the globally ‘Vulnerable’ Swan Goose Anser cygnoides winters in the Yangtze floodplain. Historically, the species was widely distributed throughout the floodplain but now approximately 95% of the population is confined to three closely-situated wetlands in Anhui

  14. Mapping Ring Particle Cooling across Saturn's Rings with Cassini CIRS

    Science.gov (United States)

    Brooks, Shawn M.; Spilker, L. J.; Edgington, S. G.; Pilorz, S. H.; Deau, E.

    2010-10-01

    Previous studies have shown that the rings' thermal inertia, a measure of their response to changes in the thermal environment, varies from ring to ring. Thermal inertia can provide insight into the physical structure of Saturn's ring particles and their regoliths. Low thermal inertia and quick temperature responses are suggestive of ring particles that have more porous or fluffy regoliths or that are riddled with cracks. Solid, coherent particles can be expected to have higher thermal inertias (Ferrari et al. 2005). Cassini's Composite Infrared Spectrometer has recorded millions of spectra of Saturn's rings since its arrival at Saturn in 2004 (personal communication, M. Segura). CIRS records far infrared radiation between 10 and 600 cm-1 (16.7 and 1000 µm) at focal plane 1 (FP1), which has a field of view of 3.9 mrad. Thermal emission from Saturn's rings peaks in this wavelength range. FP1 spectra can be used to infer ring temperatures. By tracking how ring temperatures vary, we can determine the thermal inertia of the rings. In this work we focus on CIRS observations of the shadowed portion of Saturn's rings. The thermal budget of the rings is dominated by the solar radiation absorbed by its constituent particles. When ring particles enter Saturn's shadow this source of energy is abruptly cut off. As a result, ring particles cool as they traverse Saturn's shadow. From these shadow observations we can create cooling curves at specific locations across the rings. We will show that the rings' cooling curves and thus their thermal inertia vary not only from ring to ring, but by location within the individual rings. This research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. Copyright 2010 California Institute of Technology. Government sponsorship acknowledged.

  15. Ballet in the Dark: A Critical Review of Black Swan by Darren Aronofsky

    Directory of Open Access Journals (Sweden)

    Rina Angela Corpus

    2011-12-01

    Full Text Available Choreographing the life of a ballerina in an ominous psychological thriller is a highly gendered project that takes us to well-established suspects in the patriarchal schema of the ballet world. Black Swan’s filmmakers created a narrative out of a performance of the classic ballet Swan Lake, making it a mimicry of the life of the tragic heroine Nina Sayers (Natalie Portman. The symptomatic pathology of perfectionism haunts the lead character, revealing her manifest hubris while unmasking the systemic social conditioning of women in the ballet system. These women are driven to become tenacious competitors, pleasant and willing objects of a gaze and patronage that are traditionally male-defined and controlled.

  16. Development of field-wide risk based remediation objectives for an aging oil field : Devon Canada Swan Hills Field

    Energy Technology Data Exchange (ETDEWEB)

    Brewster, M.; North, C.; Leighton-Boyce, G. [WorleyParsons Komex, Calgary, AB (Canada); Moore, D. [Devon Canada Corp., Calgary, AB (Canada)

    2006-07-01

    The development of field-wide risk based remediation objectives for the aging Devon Canada Swan Hills oil field was examined along with the key components of the closure strategy. These included source removal to the extent practical, long term monitoring, and achievable risk-based remedial objectives that were appropriate to the remote boreal forest setting of the Swan Hills field. A two stage approach was presented. The first stage involved a field wide background framework which included defining areas of common physical and ecological setting and developing appropriate exposure scenarios. The second stage involved site-specific risk assessments which included adjusting for site-specific conditions and an early demonstration project to prove the concept. A GIS approach was used to identify areas of common physical and ecological setting including: physiography; surface water; land use; vegetation ecozones; surficial and bedrock geology; and water well use. Species lists were compiled for vegetation, terrestrial wildlife (mammals, birds, amphibians), and aquatic species (fish and invertebrates). Major contaminant sources, problem formulation, vegetation bioassays, invertebrate bioassays, black spruce emergence, and guideline development were other topics covered during the presentation. Last, a summary of progress was presented. A field-wide review and development of risk zones and site-specific risk assessment has been completed. A regulatory review is underway. tabs., figs.

  17. Improving interactions between animal rights groups and conservation biologists.

    Science.gov (United States)

    Perry, Dan; Perry, Gad

    2008-02-01

    Invasive species are often considered to be a major threat to biodiversity, leading conservation biologists to often recommend their complete eradication. Animal rights groups typically categorically oppose killing animals, and their opposition has brought eradication attempts of gray squirrels in northern Italy (Europe) and mute swans in Vermont to a halt. As a result native red squirrels may disappear from Europe and ecosystem-wide impacts are expected to be caused by the swan. In contrast, cooperation between managers and animal rights groups has resulted in a successful control program for feral pigs in Fort Worth, Texas (U.S.A.). The philosophical differences between animal rights and conservation biologists' views make cooperation seem unlikely, yet documented cases of cooperation have been beneficial for both groups. We recommend that managers dealing with invasive species should consult with social scientists and ethicists to gain a better understanding of the implications of some of their policy decisions. In addition, we recommend that animal rights groups do more to support alternatives to lethal control, which are often excluded by economic limitations. Prevention of arrival of invasive species via application of the precautionary principle may be an especially productive avenue for such collaboration because it fits the goals and values of both groups.

  18. Allometry as evidence of sexual selection in monochromatic birds: the case of the Coscoroba Swan (Anseriformes: Anatidae

    Directory of Open Access Journals (Sweden)

    Cecilia P. Calabuig

    2013-08-01

    Full Text Available The Coscoroba Swan, Coscoroba coscoroba (Molina, 1782, is a poorly known aberrant Anserine endemic to South America. We captured adult birds (189 male, 157 female from the largest population in Brazil at the Taim Ecological Reserve, State of Rio Grande do Sul, Brazil. Different patterns between sexes can reflect differences in selection, and positive allometry may indicate that a character is sexually selected. We used body weight and 10 morphological measurements to examine allometric differences between males and females of C. coscoroba. Males were consistently larger than females. Analysis of scaling relationships against body mass showed that nostril, tail, wing and bill height were positively allometric (i.e., heavier birds had relatively larger character lengths, but there were no sexual differences in allometric slopes. However, for a given mass, mature females had longer tails, longer wings (up to metacarpophalangeal articulation and shorter heads than males. In the light of current debate in the literature, we discuss whether such positively allometric traits and sexual differences in scaling may be indicative of sexual selection. Although Coscoroba Swan is a monogamous species, increasing the size of some attributes may confer some advantage for mate selection or male-male competition and, contrary to other studies, we suggest that positively allometric slopes alone should not be considered as evidence for sexual selection of the considered traits.

  19. Blood biochemistry reveals malnutrition in black-necked swans (Cygnus melanocoryphus) living in a conservation priority area.

    Science.gov (United States)

    Artacho, Paulina; Soto-Gamboa, Mauricio; Verdugo, Claudio; Nespolo, Roberto F

    2007-02-01

    The application of clinical biochemical techniques to determine the products of intermediary metabolism has proved to be a reliable approach for the study of the physiological state of animals in nature. More specifically, the determination of plasma metabolites, such as glucose, total proteins (PRO), albumin (ALB), globulins (GL), urea, uric acid, triglycerides (TG) and beta-hydroxy-butyrate (BHB), and plasma enzymes such as creatine kinase (CK) and aspartate aminotransferase (AST) in wild animals is a valuable possibility for a non-destructive assessment of health in endangered populations. Since August 2004 to January 2005, we conducted a temporal study in a conservation priority site, the "Carlos Anwandter Nature Sanctuary" to determine blood biochemistry of a wild population of black-necked swans (Cygnus melanocoryphus). This population was experiencing a drastic reduction, according to the actual knowledge about yearly fluctuations in numbers and breeding pairs. In six months, we periodically sampled about 12 swans (a total of 122 individuals), which exhibited a reduction near 30% in body mass (body mass corrected by total length). Our results showed reductions in most plasma biochemical parameters (glucose, PRO, ALB, uric acid, TG) and increase in BHB, which taken together indicated signs of chronic malnutrition. Also, the increase in AST and CK that we found, together with additional evidences of sub-lethal hepatic damage (in dead individuals), and iron pollution in aquatic plants and water confirmed that water pollution was the ultimate cause of this population reduction.

  20. The Black Swans of Agricultural Education: A Glimpse into the Lived Experiences That Shape Urban Agricultural Educators' Meaning in Work

    Science.gov (United States)

    Roberts, Richie; Ramsey, Jon W.

    2017-01-01

    Urban agricultural educators face a number of unique challenges in performing their job duties. Therefore, the purpose of this study was to understand the essence of urban agricultural educators' meaning in their work by exploring their lived experiences. In this study, the essence emerged in the form of a metaphor: A Black Swan. The black swan…

  1. Testing whether macroevolution follows microevolution: are colour differences among swans (Cygnus) attributable to variation at the MCIR locus?

    Science.gov (United States)

    Pointer, Marie A; Mundy, Nicholas I

    2008-09-12

    The MC1R (melanocortin-1 receptor) locus underlies intraspecific variation in melanin-based dark plumage coloration in several unrelated birds with plumage polymorphisms. There is far less evidence for functional variants of MC1R being involved in interspecific variation, in which spurious genotype-phenotype associations arising through population history are a far greater problem than in intraspecific studies. We investigated the relationship between MC1R variation and plumage coloration in swans (Cygnus), which show extreme variation in melanic plumage phenotypes among species (white to black). The two species with melanic plumage, C. atratus and C. melanocoryphus (black and black-necked swans respectively), both have amino acid changes at important functional sites in MC1R that are consistent with increased MC1R activity and melanism. Reconstruction of MC1R evolution over a newly generated independent molecular phylogeny of Cygnus and related genera shows that these putative melanizing mutations were independently derived in the two melanic lineages. However, interpretation is complicated by the fact that one of the outgroup genera, Coscoroba, also has a putative melanizing mutation at MC1R that has arisen independently but has nearly pure white plumage. Epistasis at other loci seems the most likely explanation for this discrepancy. Unexpectedly, the phylogeny shows that the genus Cygnus may not be monophyletic, with C. melanocoryphus placed as a sister group to true geese (Anser), but further data will be needed to confirm this. Our study highlights the difficulty of extrapolating from intraspecific studies to understand the genetic basis of interspecific adaptive phenotypic evolution, even with a gene whose structure-function relationships are as well understood as MC1R as confounding variation make clear genotype/phenotype associations difficult at the macroevolutionary scale. However, the identification of substitutions in the black and black-necked swan

  2. Birds and music

    Directory of Open Access Journals (Sweden)

    L Amini

    2009-03-01

    Through research in old mythological narrations, and literary texts, one could assume an intrinsic relationship between music and such sweet-singing mythological birds as phoenix, sphinx, Song-song, holy birds like Kership-tah, and other birds including swan and ring dove.

  3. Black rings

    International Nuclear Information System (INIS)

    Emparan, Roberto; Reall, Harvey S

    2006-01-01

    A black ring is a five-dimensional black hole with an event horizon of topology S 1 x S 2 . We provide an introduction to the description of black rings in general relativity and string theory. Novel aspects of the presentation include a new approach to constructing black ring coordinates and a critical review of black ring microscopics. (topical review)

  4. Black swans or creeping normalcy? – An attempt to a holistic crisis analysis

    Directory of Open Access Journals (Sweden)

    Olivér KOVÁCS

    2013-06-01

    Full Text Available In this article we address the daunting challenge of current economic recovery by contributing to the better understanding of its secular feature. In so doing we devote special attention to the secular decline in innovativeness by raising three interlinked and interrelated explanatory phenomena: (i lowering productivity in the new techno-economic paradigm; (ii the effect of the different degree of employment protection; and (iii the issue of pent up disruptive innovations. We argue that these phenomena are not black swans; however, they have been developing in commonly unnoticed increments by manifesting the so-called ‘creeping normalcy’ and being endogenous to the market system. The paper draws lessons to be learned for the Central and Eastern European Member States as well.

  5. Variations in Ring Particle Cooling across Saturn's Rings with Cassini CIRS

    Science.gov (United States)

    Brooks, S. M.; Spilker, L. J.; Pilorz, S.; Edgington, S. G.; Déau, E.; Altobelli, N.

    2010-12-01

    Cassini's Composite Infrared Spectrometer has recorded over two million of spectra of Saturn's rings in the far infrared since arriving at Saturn in 2004. CIRS records far infrared radiation between 10 and 600 cm-1 ( 16.7 and 1000 μ {m} ) at focal plane 1 (FP1), which has a field of view of 3.9 mrad. Thermal emission from Saturn’s rings peaks in this wavelength range. Ring temperatures can be inferred from FP1 data. By tracking how ring temperatures vary, we can determine the thermal inertia of the rings. Previous studies have shown that the rings' thermal inertia, a measure of their response to changes in the thermal environment, varies from ring to ring. Thermal inertia can provide insight into the physical structure of Saturn's ring particles and their regoliths. Low thermal inertia and rapidly changing temperatures are suggestive of ring particles that have more porous or fluffy regoliths or that are riddled with cracks. Solid particles can be expected to have higher thermal inertias. Ferrari et al. (2005) fit thermal inertia values of 5218 {Jm)-2 {K}-1 {s}-1/2 to their B ring data and 6412 {Jm)-2 {K}-1 {s}-1/2 to their C ring data. In this work we focus on CIRS observations of the shadowed portion of Saturn's rings. The rings’ thermal budget is dominated by its absorption of solar radiation. As a result, ring particles abruptly cool as they traverse Saturn's shadow. From these shadow observations we can create cooling curves at specific locations across the rings. We will show that the rings' cooling curves and thus their thermal inertia vary not only from ring to ring, but by location within the individual rings. This research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. Copyright 2010 California Institute of Technology. Government sponsorship acknowledged.

  6. Swan ganz catheter for diagnosis of transient central diabetes insipidus after mitral valve replacement

    International Nuclear Information System (INIS)

    Sarwar, I.; Sinha, L.M.; Younus, A.

    2012-01-01

    Transient Diabetes Insipidus (DI) occurring in a patient undergoing open heart surgery is a rare occurrence. In this case report, we are presenting a 30 years old female patient with past history of stroke who underwent redo mitral valve replacement developed polyuria. The diagnosis of hypovolemia was made with the help of swan ganz catheter. The patient responded to desmopressin and completely recovered seven days after surgery. It is possible that transient cerebral ischemia given her history of Stroke resulted in the dysfunction of osmotic receptors in the hypothalamus or hypothalamus - pituitary axis during Cardiopulmonary Bypass (CPB). Therefore, we concluded that central DI is a probable cause of polyuria after CPB. (author)

  7. Alternative loop rings

    CERN Document Server

    Goodaire, EG; Polcino Milies, C

    1996-01-01

    For the past ten years, alternative loop rings have intrigued mathematicians from a wide cross-section of modern algebra. As a consequence, the theory of alternative loop rings has grown tremendously. One of the main developments is the complete characterization of loops which have an alternative but not associative, loop ring. Furthermore, there is a very close relationship between the algebraic structures of loop rings and of group rings over 2-groups. Another major topic of research is the study of the unit loop of the integral loop ring. Here the interaction between loop rings and group ri

  8. Primitivity and weak distributivity in near rings and matrix near rings

    International Nuclear Information System (INIS)

    Abbasi, S.J.

    1993-08-01

    This paper shows the structure of matrix near ring constructed over a weakly distributive and primative near ring. It is proved that a weakly distributive primitive near ring is a ring and the matrix near rings constructed over it is also a bag. (author). 14 refs

  9. Temperature data from buoy casts in the North Atlantic Ocean from the COLUMBUS and HMAS SWAN from 01 August 1928 to 04 September 1932 (NODC Accession 0000242)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature data were collected using buoy casts from the COLUMBUS and HMAS SWAN from August 1, 1928 to September 4, 1932 in the North Atlantic Ocean. Data were...

  10. Divine Love: The Reception of Leda and the Swan Myth in Works by Jewish and Arab Israeli Artists - Contexts and Meanings

    Directory of Open Access Journals (Sweden)

    Nava Sevilla Sadeh

    2014-09-01

    Full Text Available The motif of the abduction of a woman is one of the most frequent in Ancient Greek and Roman art. Abductions in mythology are generally portrayed as carried out by a god disguised as a human or an animal, such as Zeus who, in the form of a bull, golden rain or a swan, seduces a beautiful young maiden. These myths have been interpreted from different viewpoints, such as gender, social, political and philosophical. One of the most frequent myths of abduction is that of Leda and the Swan, which appears in both Greek and Roman painting and sculpture. This theme has found many echoes in contemporary Israeli art, and constitutes the case study for this discussion, which belongs to the field of Classical Reception studies. The interpretations of this myth are diverse, ranging from a socio-gender context, to post-colonialism and its relevance to the local situation; to subversives, concerning tradition versus contemporary culture; to emotionality and romantic suffering; and to love as phantasmagoria. These varied interpretations will be examined in the following analysis in light of both ancient concepts and contemporary outlooks, based on literary and philosophical sources.

  11. Sedimentary facies and depositional history of the Swan Islands, Honduras

    Science.gov (United States)

    Ivey, Marvin L.; Breyer, John A.; Britton, Joseph C.

    1980-10-01

    Swan Island is a Honduran possession in the western Caribbean, located on the southeastern side of the Cayman Trench. Two sedimentary assemblages are found on the island: an older bedded sequence of mid-Tertiary age (Aquitanian or Burdigalian) and a younger sedimentary sequence of Late Pleistocene age. The older sequence is composed of a series of calcarenites, calcilutites, and siliciclastic mudstones; capping these are cliff-forming reefal carbonates of the younger sequence. The rocks of the older bedded sequence accumulated in deep water. Sedimentation consisted of a constant rain of pyroclastic debris interrupted by the episodic introduction of upslope carbonate material by turbidity currents. Uplift and deformation of this sequence was initiated sometime after the Early Miocene. By the Late Pleistocene, uplift had brought the rocks into water depths conducive to coral growth. Pleistocene sedimentation on the island was controlled by the interaction between tectonic uplift and eustatic sea-level changes. The primary controlling force on the tectonic history of the island is its proximity to the boundary between the North American and Caribbean plates.

  12. Parental care in Tundra Swans during the pre-fledgling period

    Science.gov (United States)

    Earnst, Susan L.

    2002-01-01

    Among studies that have quantified the care of precocial young, few have investigated forms of parental care other than vigilance. During the pre-fledging period, Tundra Swan (Cygnus columbianus columbianus) parents provided simultaneous biparental care by foraging near each other and their cygnets, and cygnets spent more time foraging during bouts in which both parents were foraging nearby than when only one parent was foraging nearby. Parents spent nearly twice as much foraging time on land than did non-parents, a habitat in which cygnets foraged more intensely than parents (i.e., spent more time foraging during foraging bouts) and could graze on protein-rich sedges rather than use more difficult below-water foraging methods. Parents also spent more than twice as much time being vigilant and more than three times as much time defending their territory than non-parents, behaviors that presumably benefited cygents by decreasing predation risk and indirect foraging competition, respectively. Parents therefore incurred the costs of foraging less intensely during foraging bouts, spending more time interacting, more time in vigilance, and less time sleeping/preening than non-parents.

  13. Interaction of ring dark solitons with ring impurities in Bose-Einstein condensates

    International Nuclear Information System (INIS)

    Xue Jukui

    2005-01-01

    The interaction of ring dark solitons/vortexes with the ring-shaped repulsive and attractive impurities in two-dimensional Bose-Einstein condensates is investigated numerically. Very rich interaction phenomena are obtained, i.e., not only the interaction between the ring soliton and the impurity, but also the interaction between vortexes and the impurity. The interaction characters, i.e., snaking of ring soliton, quasitrapping or reflection of ring soliton and vortexes by the impurity, strongly depend on initial ring soliton velocity, impurity strength, initial position of ring soliton and impurity. The numerical results also reveal that ring dark solitons/vortexes can be trapped and dragged by an adiabatically moving attractive ring impurity

  14. Storage Rings

    International Nuclear Information System (INIS)

    Fischer, W.

    2010-01-01

    Storage rings are circular machines that store particle beams at a constant energy. Beams are stored in rings without acceleration for a number of reasons (Tab. 1). Storage rings are used in high-energy, nuclear, atomic, and molecular physics, as well as for experiments in chemistry, material and life sciences. Parameters for storage rings such as particle species, energy, beam intensity, beam size, and store time vary widely depending on the application. The beam must be injected into a storage ring but may not be extracted (Fig. 1). Accelerator rings such as synchrotrons are used as storage rings before and after acceleration. Particles stored in rings include electrons and positrons; muons; protons and anti-protons; neutrons; light and heavy, positive and negative, atomic ions of various charge states; molecular and cluster ions, and neutral polar molecules. Spin polarized beams of electrons, positrons, and protons were stored. The kinetic energy of the stored particles ranges from 10 -6 eV to 3.5 x 10 12 eV (LHC, 7 x 10 12 eV planned), the number of stored particles from one (ESR) to 1015 (ISR). To store beam in rings requires bending (dipoles) and transverse focusing (quadrupoles). Higher order multipoles are used to correct chromatic aberrations, to suppress instabilities, and to compensate for nonlinear field errors of dipoles and quadrupoles. Magnetic multipole functions can be combined in magnets. Beams are stored bunched with radio frequency systems, and unbunched. The magnetic lattice and radio frequency system are designed to ensure the stability of transverse and longitudinal motion. New technologies allow for better storage rings. With strong focusing the beam pipe dimensions became much smaller than previously possible. For a given circumference superconducting magnets make higher energies possible, and superconducting radio frequency systems allow for efficient replenishment of synchrotron radiation losses of large current electron or positron beams

  15. Rings in drugs.

    Science.gov (United States)

    Taylor, Richard D; MacCoss, Malcolm; Lawson, Alastair D G

    2014-07-24

    We have analyzed the rings, ring systems, and frameworks in drugs listed in the FDA Orange Book to understand the frequency, timelines, molecular property space, and the application of these rings in different therapeutic areas and target classes. This analysis shows that there are only 351 ring systems and 1197 frameworks in drugs that came onto the market before 2013. Furthermore, on average six new ring systems enter drug space each year and approximately 28% of new drugs contain a new ring system. Moreover, it is very unusual for a drug to contain more than one new ring system and the majority of the most frequently used ring systems (83%) were first used in drugs developed prior to 1983. These observations give insight into the chemical novelty of drugs and potentially efficient ways to assess compound libraries and develop compounds from hit identification to lead optimization and beyond.

  16. The influence of collisional transfer effects on measured C2 Swan band transition probabilities

    International Nuclear Information System (INIS)

    Erman, P.

    1980-01-01

    Lifetime and relative intensities of the C 2 (d - a) Swan bands have been remeasured using the High Frequency Deflection technique, yielding tau(d, γ = 0-6) = 120 +- 4ns. With increasing pressure of the C 2 H 2 target gas strong second lifetime components occur revealing collisional transfers from other C 2 levles with rate coefficients around 6 X 10 -11 cm 3 s -1 mol -1 . These transfers are also observed with a number of other catalyser gases such as He, Ne, Ar, N 2 , and CO 2 . The transfer processes explain the considerably longer lifetimes reported in several earlier lifetime investigations and could be a clue to the formation mechanism of the carbon high pressure bands. (Auth.)

  17. White Ring; White ring

    Energy Technology Data Exchange (ETDEWEB)

    Aoki, H.; Yuzawa, H. [Nikken Sekkei Ltd., Osaka (Japan)

    1998-01-05

    White Ring is a citizen`s gymnasium used for figure skating and short track speed skating games of 18th Winter Olympic Games in 1998. White Ring is composed of a main-arena and a sub-arena. For the main-arena with an area 41mtimes66m, an ice link can be made by disengaging the potable floor and by flowing brine in the bridged polystyrene pipes embedded in the concrete floor. Due to the fortunate groundwater in this site, well water is used for the outside air treatment energy in 63% during heating and in 35% during cooling. Ammonia is used as a cooling medium for refrigerating facility. For the heating of audience area in the large space, heat load from the outside is reduced by enhancing the heat insulation performance of the roof of arena. The audience seats are locally heated using heaters. For the White Ring, high quality environment is realized for games through various functions of the large-scale roof of the large space. Success of the big event was expected. 15 figs., 4 tabs.

  18. Token Ring Project

    Directory of Open Access Journals (Sweden)

    Adela Ionescu

    2007-01-01

    Full Text Available Ring topology is a simple configuration used to connect processes that communicate among themselves. A number of network standards such as token ring, token bus, and FDDI are based on the ring connectivity. This article will develop an implementation of a ring of processes that communicate among themselves via pipe links. The processes are nodes in the ring. Each process reads from its standard input and writes in its standard output. N-1 process redirects the its standard output to a standard input of the process through a pipe. When the ring-structure is designed, the project can be extended to simulate networks or to implement algorithms for mutual exclusion

  19. Semi-algebraic function rings and reflectors of partially ordered rings

    CERN Document Server

    Schwartz, Niels

    1999-01-01

    The book lays algebraic foundations for real geometry through a systematic investigation of partially ordered rings of semi-algebraic functions. Real spectra serve as primary geometric objects, the maps between them are determined by rings of functions associated with the spectra. The many different possible choices for these rings of functions are studied via reflections of partially ordered rings. Readers should feel comfortable using basic algebraic and categorical concepts. As motivational background some familiarity with real geometry will be helpful. The book aims at researchers and graduate students with an interest in real algebra and geometry, ordered algebraic structures, topology and rings of continuous functions.

  20. Overview of incursions of Asian H5N1 subtype highly pathogenic avian influenza virus into Great Britain, 2005-2008.

    Science.gov (United States)

    Alexander, Dennis J; Manvell, Ruth J; Irvine, Richard; Londt, Brandon Z; Cox, Bill; Ceeraz, Vanessa; Banks, Jill; Browna, Ian H

    2010-03-01

    Since 2005 there have been five incursions into Great Britain of highly pathogenic avian influenza (HPAI) viruses of subtype H5N1 related to the ongoing global epizootic. The first incursion occurred in October 2005 in birds held in quarantine after importation from Taiwan. Two incursions related to wild birds: one involved a single dead whooper swan found in March 2006 in the sea off the east coast of Scotland, and the other involved 10 mute swans and a Canada goose found dead over the period extending from late December 2007 to late February 2008 on or close to a swannery on the south coast of England. The other two outbreaks occurred in commercial poultry in January 2007 and November 2007, both in the county of Suffolk. The first of these poultry outbreaks occurred on a large turkey farm, and there was no further spread. The second outbreak occurred on a free-range farm rearing turkeys, ducks, and geese and spread to birds on a second turkey farm that was culled as a dangerous contact. Viruses isolated from these five outbreaks were confirmed to be Asian H5N1 HPAI viruses; the quarantine outbreak was attributed to a clade 2.3 virus and the other four to clade 2.2 viruses. This article describes the outbreaks, their control, and the possible origins of the responsible viruses.

  1. Testing whether macroevolution follows microevolution: Are colour differences among swans (Cygnus attributable to variation at the MC1R locus?

    Directory of Open Access Journals (Sweden)

    Pointer Marie A

    2008-09-01

    Full Text Available Abstract Background The MC1R (melanocortin-1 receptor locus underlies intraspecific variation in melanin-based dark plumage coloration in several unrelated birds with plumage polymorphisms. There is far less evidence for functional variants of MC1R being involved in interspecific variation, in which spurious genotype-phenotype associations arising through population history are a far greater problem than in intraspecific studies. We investigated the relationship between MC1R variation and plumage coloration in swans (Cygnus, which show extreme variation in melanic plumage phenotypes among species (white to black. Results The two species with melanic plumage, C. atratus and C. melanocoryphus (black and black-necked swans respectively, both have amino acid changes at important functional sites in MC1R that are consistent with increased MC1R activity and melanism. Reconstruction of MC1R evolution over a newly generated independent molecular phylogeny of Cygnus and related genera shows that these putative melanizing mutations were independently derived in the two melanic lineages. However, interpretation is complicated by the fact that one of the outgroup genera, Coscoroba, also has a putative melanizing mutation at MC1R that has arisen independently but has nearly pure white plumage. Epistasis at other loci seems the most likely explanation for this discrepancy. Unexpectedly, the phylogeny shows that the genus Cygnus may not be monophyletic, with C. melanocoryphus placed as a sister group to true geese (Anser, but further data will be needed to confirm this. Conclusion Our study highlights the difficulty of extrapolating from intraspecific studies to understand the genetic basis of interspecific adaptive phenotypic evolution, even with a gene whose structure-function relationships are as well understood as MC1R as confounding variation make clear genotype/phenotype associations difficult at the macroevolutionary scale. However, the identification

  2. Rotating ring-ring electrode theory and experiment

    NARCIS (Netherlands)

    Kuiken, H.K.; Bakkers, E.P.A.M.; Ligthart, H.; Kellyb, J.J.

    2000-01-01

    A model is presented for the rotating ring-ring electrode. Although the electrode is defined by four characteristic lengths, it is shown that the collection efficiency depends on only two dimensionless parameters. A simple relationship between these and the corresponding parameters for the rotating

  3. Drivers of waterfowl population dynamics: from teal to swans

    Science.gov (United States)

    Koons, David N.; Gunnarsson, Gunnar; Schmutz, Joel A.; Rotella, Jay J.

    2014-01-01

    Waterfowl are among the best studied and most extensively monitored species in the world. Given their global importance for sport and subsistence hunting, viewing and ecosystem functioning, great effort has been devoted since the middle part of the 20th century to understanding both the environmental and demographic mechanisms that influence waterfowl population and community dynamics. Here we use comparative approaches to summarise and contrast our understanding ofwaterfowl population dynamics across species as short-lived as the teal Anas discors and A.crecca to those such as the swans Cygnus sp. which have long life-spans. Specifically, we focus on population responses to vital rate perturbations across life history strategies, discuss bottom-up and top-down responses of waterfowlpopulations to global change, and summarise our current understanding of density dependence across waterfowl species. We close by identifying research needs and highlight ways to overcome the challenges of sustainably managing waterfowl populations in the 21st century.

  4. Water production in comets C/2011 L4 (PanSTARRS) and C/2012 F6 (Lemmon) from observations with Soho/Swan

    International Nuclear Information System (INIS)

    Combi, M. R.; Aptekar, G.; Bertaux, J.-L.; Quémerais, E.; Ferron, S.; Mäkinen, J. T. T.

    2014-01-01

    Comets C/2011 L4 (PanSTARRS) and C/2012 F6 (Lemmon) were observed throughout their 2012-2013 apparitions with the Solar Wind Anisotropies (SWAN) all-sky hydrogen Lyα camera on board the Solar and Heliosphere Observatory (SOHO) satellite. SOHO has been in a halo orbit around the L1 Earth-Sun Lagrange point since early 1996 and has been observing the interplanetary medium and comets beginning with C/1996 B2 (Hyakutake). The global water production from these comets was determined from an analysis of the SWAN Lyα camera observations. Comet C/2011 L4 (PanSTARRS), which reached its perihelion distance of 0.302 AU on 2013 March 10.17, was observed on 50 days between 2013 January 29 and April 30. Comet C/2012 F6 (Lemmon), which reached its perihelion distance of 0.731 AU on 2013 March 24.51, was observed on 109 days between 2012 November 29 and 2013 June 31. The maximum water production rates were ∼1 × 10 30 molecules s –1 for both comets. The activities of both comets were asymmetric about perihelion. C/2011 L4 (PanSTARRS) was more active before perihelion than after, but C/2012 F6 (Lemmon) was more active after perihelion than before.

  5. Topological ring currents in the "empty" ring of benzo-annelated perylenes.

    Science.gov (United States)

    Dickens, Timothy K; Mallion, Roger B

    2011-01-27

    Cyclic conjugation in benzo-annelated perylenes is examined by means of the topological π-electron ring currents calculated for each of their constituent rings, in a study that is an exact analogy of a recent investigation by Gutman et al. based on energy-effect values for the corresponding rings in each of these structures. "Classical" approaches, such as Kekulé structures, Clar "sextet" formulas, and circuits of conjugation, predict that the central ring in perylene is "empty" and thus contributes negligibly to cyclic conjugation. However, conclusions from the present calculations of topological ring currents agree remarkably with those arising from the earlier study involving energy-effect values in that, contrary to what would be predicted from the classical approaches, rings annelated in an angular fashion relative to the central ring of these perylene structures materially increase the extent of that ring's involvement in cyclic conjugation. It is suggested that such close quantitative agreement between the predictions of these two superficially very different indices (energy effect and topological ring current) might be due to the fact that, ultimately, both depend, albeit in ostensibly quite different ways, only on an adjacency matrix that contains information about the carbon-carbon connectivity of the conjugated system in question.

  6. Kayser-Fleischer Rings

    Science.gov (United States)

    ... Support Contacts Lab Tracker/Copper Calculator Stories Programs & Research ... About Everything you need to know about Wilson Disease Kayser-Fleischer Rings Definition Kayser-Fleischer Ring: Clinical sign. Brownish-yellow ring visible around the corneo- ...

  7. The Interstellar H Flow: Updated Analysis of SOHO/SWAN Data

    International Nuclear Information System (INIS)

    Lallement, Rosine; Quemerais, Eric; Bertaux, Jean-Loup; Ferron, Stephane; Koutroumpa, Dimitra; Schmidt, Walter; Lamy, Philippe

    2010-01-01

    We update two kinds of results obtained with the SWAN instrument on board SOHO. First, we use H cell data recorded in 2001 and derive the H flow direction in the same way the study was done at solar minimum. We again compare with the Helium flow direction and doing so correct for the coordinate system change between the Ulysses and SOHO missions. The deflection plane we obtain is compatible with our previous result within error bars, confirming the potential predominant role of the interstellar magnetic field. In a second part, we extend the computation of the interstellar H ionization as a function of heliographic latitude and time, a quantity which reflects closely the SW flux latitudinal structure. The pattern for the present solar minimum is strikingly different from the previous minimum, with a much wider slow solar wind equatorial belt which persists until at least 2008. Comparing with synoptic LASCO/C2 electron densities we infer from a preliminary study that the acceleration of the high speed solar wind occurs at a higher altitude during this minimum compared to the previous one, a difference expansion models must be able to reproduce.

  8. Water production rates of recent comets (2016-2017) by SOHO/SWAN: 2P/Encke, 41P/Tuttle-Giacobini-Kresak, 45P/ Honda-Mrkos-Pajdusakova, and C/2015 ER61 (PanSTARRS)

    Science.gov (United States)

    Combi, Michael R.; Mäkinen, Terhi; Bertaux, Jean-Loup; Quémerais, Eric; Ferron, Stephane

    2017-10-01

    The all-sky hydrogen Lyman-alpha camera, SWAN (Solar Wind Anisotropies), on the SOlar and Heliospheric Observatory (SOHO) satellite makes observations of the hydrogen coma of comets. Most water molecules produced by comets are ultimately photodissociated into two H atoms and one O atom producing a huge atomic hydrogen coma that is routinely observed in the daily full-sky SWAN images in comets of sufficient brightness. Water production rates are calculated using our time-resolved model (Mäkinen & Combi, 2005, Icarus 177, 217), typically yielding about 1 observation every 2 days on the average for each comet over the brightest part of its apparition. Here we describe the progress in analysis of observations of comets observed in 2016 and 2017. These include comets 2P/Encke, 41P/Tuttle-Giacobini-Sresak, 45P/ Honda-Mrkos-Pajdusakova, and C/2015 ER61 (PanSTARRS). A status update on the entire SOHO/SWAN archive of water production rates in comets will also be given.SOHO is an international cooperative mission between ESA and NASA. Support from grants NNX15AJ81G from the NASA Solar System Observations Planetary Astronomy Program and a previous grant NNX13AQ66G from the NASA Planetary Mission Data Analysis Program are gratefully acknowledged, as is support from CNRS, CNES, and the Finnish Meteorological Institute (FMI).

  9. Planetary Rings

    Science.gov (United States)

    Nicholson, P. D.

    2001-11-01

    A revolution in the studies in planetary rings studies occurred in the period 1977--1981, with the serendipitous discovery of the narrow, dark rings of Uranus, the first Voyager images of the tenuous jovian ring system, and the many spectacular images returned during the twin Voyager flybys of Saturn. In subsequent years, ground-based stellar occultations, HST observations, and the Voyager flybys of Uranus (1986) and Neptune (1989), as well as a handful of Galileo images, provided much additional information. Along with the completely unsuspected wealth of detail these observations revealed came an unwelcome problem: are the rings ancient or are we privileged to live at a special time in history? The answer to this still-vexing question may lie in the complex gravitational interactions recent studies have revealed between the rings and their retinues of attendant satellites. Among the four known ring systems, we see elegant examples of Lindblad and corotation resonances (first invoked in the context of galactic disks), electromagnetic resonances, spiral density waves and bending waves, narrow ringlets which exhibit internal modes due to collective instabilities, sharp-edged gaps maintained via tidal torques from embedded moonlets, and tenuous dust belts created by meteoroid impact onto parent bodies. Perhaps most puzzling is Saturn's multi-stranded, clumpy F ring, which continues to defy a simple explanation 20 years after it was first glimpsed in grainy images taken by Pioneer 11. Voyager and HST images reveal a complex, probably chaotic, dynamical interaction between unseen parent bodies within this ring and its two shepherd satellites, Pandora and Prometheus. The work described here reflects contributions by Joe Burns, Jeff Cuzzi, Luke Dones, Dick French, Peter Goldreich, Colleen McGhee, Carolyn Porco, Mark Showalter, and Bruno Sicardy, as well as those of the author. This research has been supported by NASA's Planetary Geology and Geophysics program and the

  10. Testing The ‘Black Swan Effect’ on Croatian Stock Market Between 2000 and 2013

    Directory of Open Access Journals (Sweden)

    Anita Radman Peša

    2016-02-01

    Full Text Available We tested the economic activity and stock exchange of Croatia as a new country of EU in order to investigate the ‘Black Swan effect’ from 2000 to 2013. The empirical findings obtained in application of OLS methodology and Chow breaking point test provide evidence and show that resignation of the Croatian ex Prime Minister lead country successfully to EU, but were also ‘The Black Swan’ event, being unpredictable and having huge impact on political and economic environment in Croatia obtained through CROBEX, Croatian stock exchange indices. Authors conclude that the resignation was connected to one of the first significant cases of corruption in Croatia which has got the negative impact on the economic development of the country in general, dealing at the same time with global recession.

  11. Preparation for electron ring - plasma ring merging experiments in RECE-MERGE

    International Nuclear Information System (INIS)

    Taggart, D.; Sekiguchi, A.; Fleischmann, H.H.

    1986-01-01

    The formation of a mixed-CT using relativistic electron rings and gun-produced plasma rings by MERGE-ing them axially is simulated. This process is similar to the axial stacking of relativistic electron rings in RECE-Christa. The results of their first plasm production experiment are reported here. After study of the gun-produced plasma's properties is completed, the gun will be mounted at the downstream end of the vacuum tank and the source of relativistic electron rings will be at the upstream end. The two rings, formed at opposite ends of the tank, will be translated axially and merged

  12. Mass production of 'Swan's Golden', Cupressus sempervirens by tissue culture and its radiation breeding. 2. Study on growth regulating substance to stimulate the elongation of shoot apex

    International Nuclear Information System (INIS)

    Suda, Hirokatsu

    1997-01-01

    Some species of 'Swan's Golden' have been propagated by means of grafting because propagation by cutting is difficult. However, not a few species of the plant are easily lodged, resulting that spreading of 'Swan's Golden' is difficult. Here, an investigation was made on growth regulating substances added into the basal medium in respects of their kinds and concentrations and also the kind of medium for successive culture. As the basal medium, SH medium supplemented with 4 g/l of gel-light and 3 g/l of carbon-powder was used. The optimum medium for the initiation of culture was the basal medium added with zeatin (Ze) and gibberellin (GA) and it was also suitable for successive culture after the 14 day. The medium added with Ze and benzyladenine (BA) or Ze alone was found to be most suitable for the culture after the 28 day. The concentration was optimum at 1 - 2.5 mg/l for either of these growth regulating substances. (M.N.)

  13. Population, behavioural and physiological responses of an urban population of black swans to an intense annual noise event.

    Science.gov (United States)

    Payne, Catherine J; Jessop, Tim S; Guay, Patrick-Jean; Johnstone, Michele; Feore, Megan; Mulder, Raoul A

    2012-01-01

    Wild animals in urban environments are exposed to a broad range of human activities that have the potential to disturb their life history and behaviour. Wildlife responses to disturbance can range from emigration to modified behaviour, or elevated stress, but these responses are rarely evaluated in concert. We simultaneously examined population, behavioural and hormonal responses of an urban population of black swans Cygnus atratus before, during and after an annual disturbance event involving large crowds and intense noise, the Australian Formula One Grand Prix. Black swan population numbers were lowest one week before the event and rose gradually over the course of the study, peaking after the event, suggesting that the disturbance does not trigger mass emigration. We also found no difference in the proportion of time spent on key behaviours such as locomotion, foraging, resting or self-maintenance over the course of the study. However, basal and capture stress-induced corticosterone levels showed significant variation, consistent with a modest physiological response. Basal plasma corticosterone levels were highest before the event and decreased over the course of the study. Capture-induced stress levels peaked during the Grand Prix and then also declined over the remainder of the study. Our results suggest that even intensely noisy and apparently disruptive events may have relatively low measurable short-term impact on population numbers, behaviour or physiology in urban populations with apparently high tolerance to anthropogenic disturbance. Nevertheless, the potential long-term impact of such disturbance on reproductive success, individual fitness and population health will need to be carefully evaluated.

  14. Population, behavioural and physiological responses of an urban population of black swans to an intense annual noise event.

    Directory of Open Access Journals (Sweden)

    Catherine J Payne

    Full Text Available Wild animals in urban environments are exposed to a broad range of human activities that have the potential to disturb their life history and behaviour. Wildlife responses to disturbance can range from emigration to modified behaviour, or elevated stress, but these responses are rarely evaluated in concert. We simultaneously examined population, behavioural and hormonal responses of an urban population of black swans Cygnus atratus before, during and after an annual disturbance event involving large crowds and intense noise, the Australian Formula One Grand Prix. Black swan population numbers were lowest one week before the event and rose gradually over the course of the study, peaking after the event, suggesting that the disturbance does not trigger mass emigration. We also found no difference in the proportion of time spent on key behaviours such as locomotion, foraging, resting or self-maintenance over the course of the study. However, basal and capture stress-induced corticosterone levels showed significant variation, consistent with a modest physiological response. Basal plasma corticosterone levels were highest before the event and decreased over the course of the study. Capture-induced stress levels peaked during the Grand Prix and then also declined over the remainder of the study. Our results suggest that even intensely noisy and apparently disruptive events may have relatively low measurable short-term impact on population numbers, behaviour or physiology in urban populations with apparently high tolerance to anthropogenic disturbance. Nevertheless, the potential long-term impact of such disturbance on reproductive success, individual fitness and population health will need to be carefully evaluated.

  15. Ring faults and ring dikes around the Orientale basin on the Moon.

    Science.gov (United States)

    Andrews-Hanna, Jeffrey C; Head, James W; Johnson, Brandon; Keane, James T; Kiefer, Walter S; McGovern, Patrick J; Neumann, Gregory A; Wieczorek, Mark A; Zuber, Maria T

    2018-08-01

    The Orientale basin is the youngest and best-preserved multiring impact basin on the Moon, having experienced only modest modification by subsequent impacts and volcanism. Orientale is often treated as the type example of a multiring basin, with three prominent rings outside of the inner depression: the Inner Rook Montes, the Outer Rook Montes, and the Cordillera. Here we use gravity data from NASA's Gravity Recovery and Interior Laboratory (GRAIL) mission to reveal the subsurface structure of Orientale and its ring system. Gradients of the gravity data reveal a continuous ring dike intruded into the Outer Rook along the plane of the fault associated with the ring scarp. The volume of this ring dike is ~18 times greater than the volume of all extrusive mare deposits associated with the basin. The gravity gradient signature of the Cordillera ring indicates an offset along the fault across a shallow density interface, interpreted to be the base of the low-density ejecta blanket. Both gravity gradients and crustal thickness models indicate that the edge of the central cavity is shifted inward relative to the equivalent Inner Rook ring at the surface. Models of the deep basin structure show inflections along the crust-mantle interface at both the Outer Rook and Cordillera rings, indicating that the basin ring faults extend from the surface to at least the base of the crust. Fault dips range from 13-22° for the Cordillera fault in the northeastern quadrant, to 90° for the Outer Rook in the northwestern quadrant. The fault dips for both outer rings are lowest in the northeast, possibly due to the effects of either the direction of projectile motion or regional gradients in pre-impact crustal thickness. Similar ring dikes and ring faults are observed around the majority of lunar basins.

  16. Groups, rings, modules

    CERN Document Server

    Auslander, Maurice

    2014-01-01

    This classic monograph is geared toward advanced undergraduates and graduate students. The treatment presupposes some familiarity with sets, groups, rings, and vector spaces. The four-part approach begins with examinations of sets and maps, monoids and groups, categories, and rings. The second part explores unique factorization domains, general module theory, semisimple rings and modules, and Artinian rings. Part three's topics include localization and tensor products, principal ideal domains, and applications of fundamental theorem. The fourth and final part covers algebraic field extensions

  17. Social Media and the Role in Spreading Social Unification Mutes in the Family

    Directory of Open Access Journals (Sweden)

    Ali Amani

    2018-01-01

    Full Text Available The effect of new media social not only on the children; but on the whole family was and still has Serious impact and dangerous to the community and the next generation and probably a lot of family relationship failed, and deteriorating. Perhaps explained in this paper some of which can be done to avoid those problems that brought us more of the West and traditions. They try to be with the children as a family with communication. Approximately 60% of educational concepts and ethics, behavior and belief sourced media. The Toxins That Threaten Our Brain (The reflection of communication in family relation a. Understanding the wellbeing of the children and young people. b. Issues for consideration in conceptualizing the wellbeing of the children and young people. c. Identify emerging trends concerning the psychological and emotional wellbeing needs of children and young people. Identify and determine the relationships between parents and young people make them able of dealing with others, not only online and away their social and family mutes. At the same time though, overall Internet use keeping family member apart. Online social networks are more than just a fad among the younger generation, “Lynn Franco, director of The Conference Board Consumer Research Center, in a statement. “They’ve become an integral part of our personal and professional lives. They’re an effective way to keep in touch with people, connect with friends and family, and network with colleagues and all that online if they see each other they don’t jnow how to communicate. ”

  18. Saturn's Rings Edge-on

    Science.gov (United States)

    1995-01-01

    In one of nature's most dramatic examples of 'now-you see-them, now-you-don't', NASA's Hubble Space Telescope captured Saturn on May 22, 1995 as the planet's magnificent ring system turned edge-on. This ring-plane crossing occurs approximately every 15 years when the Earth passes through Saturn's ring plane.For comparison, the top picture was taken by Hubble on December 1, 1994 and shows the rings in a more familiar configuration for Earth observers.The bottom picture was taken shortly before the ring plane crossing. The rings do not disappear completely because the edge of the rings reflects sunlight. The dark band across the middle of Saturn is the shadow of the rings cast on the planet (the Sun is almost 3 degrees above the ring plane.) The bright stripe directly above the ring shadow is caused by sunlight reflected off the rings onto Saturn's atmosphere. Two of Saturn's icy moons are visible as tiny starlike objects in or near the ring plane. They are, from left to right, Tethys (slightly above the ring plane) and Dione.This observation will be used to determine the time of ring-plane crossing and the thickness of the main rings and to search for as yet undiscovered satellites. Knowledge of the exact time of ring-plane crossing will lead to an improved determination of the rate at which Saturn 'wobbles' about its axis (polar precession).Both pictures were taken with Hubble's Wide Field Planetary Camera 2. The top image was taken in visible light. Saturn's disk appears different in the bottom image because a narrowband filter (which only lets through light that is not absorbed by methane gas in Saturn's atmosphere) was used to reduce the bright glare of the planet. Though Saturn is approximately 900 million miles away, Hubble can see details as small as 450 miles across.The Wide Field/Planetary Camera 2 was developed by the Jet Propulsion Laboratory and managed by the Goddard Spaced Flight Center for NASA's Office of Space Science.This image and other images and

  19. The Rotating Ring-Ring Electrode. Theory and Experiment

    NARCIS (Netherlands)

    Kuiken, H.K.; Bakkers, E.P.A.M.; Ligthart, H.; Kelly, J.J.

    2000-01-01

    A model is presented for the rotating ring-ring electrode. Although the electrode is defined by four characteristic lengths, it is shown that the collection efficiency depends on only two dimensionless parameters. A simple relationship between these and the corresponding parameters for the rotating

  20. Wear Analysis of Top Piston Ring to Reduce Top Ring Reversal Bore Wear

    Directory of Open Access Journals (Sweden)

    P. Ilanthirayan

    2017-12-01

    Full Text Available The piston rings are the most important part in engine which controls the lubricating oil consumption and blowby of the gases. The lubricating film of oil is provided to seal of gases towards crankcase and also to give smooth friction free translatory motion between rings and liner. Of the three rings present top ring is more crucial as it does the main work of restricting gases downwards the crankcase. Boundary lubrication is present at the Top dead centre (TDC and Bottom dead centre (BDC of the liner surface. In addition to this, top ring is exposed to high temperature gases which makes the oil present near the top ring to get evaporated and decreasing its viscosity, making metal-metal contact most of the time. Due to this at TDC, excess wear happens on the liner which is termed as Top ring reversal bore wear. The wear rate depends upon many parameters such as lubrication condition, viscosity index, contact type, normal forces acting on ring, geometry of ring face, surface roughness, material property. The present work explores the wear depth for different geometries of barrel ring using Finite Element model with the help of Archard wear law and the same is validated through experimentation. The study reveals that Asymmetric barrel rings have less contact pressure which in turn reduces the wear at Top dead centre.

  1. PREFACE: Special section on vortex rings Special section on vortex rings

    Science.gov (United States)

    Fukumoto, Yasuhide

    2009-10-01

    This special section of Fluid Dynamics Research includes five articles on vortex rings in both classical and quantum fluids. The leading scientists of the field describe the trends in and the state-of-the-art development of experiments, theories and numerical simulations of vortex rings. The year 2008 was the 150th anniversary of 'vortex motion' since Hermann von Helmholtz opened up this field. In 1858, Helmholtz published a paper in Crelle's Journal which put forward the concept of 'vorticity' and made the first analysis of vortex motion. Fluid mechanics before that was limited to irrotational motion. In the absence of vorticity, the motion of an incompressible homogeneous fluid is virtually equivalent to a rigid-body motion in the sense that the fluid motion is determined once the boundary configuration is specified. Helmholtz proved, among other things, that, without viscosity, a vortex line is frozen into the fluid. This Helmholtz's law immediately implies the preservation of knots and links of vortex lines and its implication is enormous. One of the major trends of fluid mechanics since the latter half of the 20th century is to clarify the topological meaning of Helmholtz's law and to exploit it to develop theoretical and numerical methods to find the solutions of the Euler equations and to develop experimental techniques to gain an insight into fluid motion. Vortex rings are prominent coherent structures in a variety of fluid motions from the microscopic scale, through human and mesoscale to astrophysical scales, and have attracted people's interest. The late professor Philip G Saffman (1981) emphasized the significance of studies on vortex rings. One particular motion exemplifies the whole range of problems of vortex motion and is also a commonly known phenomenon, namely the vortex ring or smoke ring. Vortex rings are easily produced by dropping drops of one liquid into another, or by puffing fluid out of a hole, or by exhaling smoke if one has the skill

  2. Vortex rings

    CERN Document Server

    Akhmetov, D G

    2009-01-01

    This text on vortex rings covers their theoretical foundation, systematic investigations, and practical applications such as the extinction of fires at gushing oil wells. It pays special attention to the formation and motion of turbulent vortex rings.

  3. The Swiss Black Swan Bad Scenario: Is Switzerland Another Casualty of the Eurozone Crisis?

    Directory of Open Access Journals (Sweden)

    Sebastien Lleo

    2015-08-01

    Full Text Available Financial disasters to hedge funds, bank trading departments and individual speculative traders and investors seem to always occur because of non-diversification in all possible scenarios, being overbet and being hit by a bad scenario. Black swans are the worst type of bad scenario: unexpected and extreme. The Swiss National Bank decision on 15 January 2015 to abandon the 1.20 peg against the Euro was a tremendous blow for many Swiss exporters, but also Swiss and international investors, hedge funds, global macro funds, banks, as well as the Swiss central bank. In this paper, we discuss the causes for this action, the money losers and the few winners, what it means for Switzerland, Europe and the rest of the world, what kinds of trades were lost and how they have been prevented.

  4. FUZZY RINGS AND ITS PROPERTIES

    Directory of Open Access Journals (Sweden)

    Karyati Karyati

    2017-01-01

      One of algebraic structure that involves a binary operation is a group that is defined  an un empty set (classical with an associative binary operation, it has identity elements and each element has an inverse. In the structure of the group known as the term subgroup, normal subgroup, subgroup and factor group homomorphism and its properties. Classical algebraic structure is developed to algebraic structure fuzzy by the researchers as an example semi group fuzzy and fuzzy group after fuzzy sets is introduced by L. A. Zadeh at 1965. It is inspired of writing about semi group fuzzy and group of fuzzy, a research on the algebraic structure of the ring is held with reviewing ring fuzzy, ideal ring fuzzy, homomorphism ring fuzzy and quotient ring fuzzy with its properties. The results of this study are obtained fuzzy properties of the ring, ring ideal properties fuzzy, properties of fuzzy ring homomorphism and properties of fuzzy quotient ring by utilizing a subset of a subset level  and strong level  as well as image and pre-image homomorphism fuzzy ring.   Keywords: fuzzy ring, subset level, homomorphism fuzzy ring, fuzzy quotient ring

  5. Polarization Insensitivity in Double-Split Ring and Triple-Split Ring Terahertz Resonators

    International Nuclear Information System (INIS)

    Wu Qian-Nan; Lan Feng; Tang Xiao-Pin; Yang Zi-Qiang

    2015-01-01

    A modified double-split ring resonator and a modified triple-split ring resonator, which offer polarization-insensitive performance, are investigated, designed and fabricated. By displacing the two gaps of the conventional double-split ring resonator away from the center, the second resonant frequency for the 0° polarized wave and the resonant frequency for the 90° polarized wave become increasingly close to each other until they are finally identical. Theoretical and experimental results show that the modified double-split ring resonator and the modified triple-split ring resonator are insensitive to different polarized waves and show strong resonant frequency dips near 433 and 444 GHz, respectively. The results of this work suggest new opportunities for the investigation and design of polarization-dependent terahertz devices based on split ring resonators. (paper)

  6. RINGED ACCRETION DISKS: EQUILIBRIUM CONFIGURATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Pugliese, D.; Stuchlík, Z., E-mail: d.pugliese.physics@gmail.com, E-mail: zdenek.stuchlik@physics.cz [Institute of Physics and Research Centre of Theoretical Physics and Astrophysics, Faculty of Philosophy and Science, Silesian University in Opava, Bezručovo náměstí 13, CZ-74601 Opava (Czech Republic)

    2015-12-15

    We investigate a model of a ringed accretion disk, made up by several rings rotating around a supermassive Kerr black hole attractor. Each toroid of the ringed disk is governed by the general relativity hydrodynamic Boyer condition of equilibrium configurations of rotating perfect fluids. Properties of the tori can then be determined by an appropriately defined effective potential reflecting the background Kerr geometry and the centrifugal effects. The ringed disks could be created in various regimes during the evolution of matter configurations around supermassive black holes. Therefore, both corotating and counterrotating rings have to be considered as being a constituent of the ringed disk. We provide constraints on the model parameters for the existence and stability of various ringed configurations and discuss occurrence of accretion onto the Kerr black hole and possible launching of jets from the ringed disk. We demonstrate that various ringed disks can be characterized by a maximum number of rings. We present also a perturbation analysis based on evolution of the oscillating components of the ringed disk. The dynamics of the unstable phases of the ringed disk evolution seems to be promising in relation to high-energy phenomena demonstrated in active galactic nuclei.

  7. Stirling engine piston ring

    Science.gov (United States)

    Howarth, Roy B.

    1983-01-01

    A piston ring design for a Stirling engine wherein the contact pressure between the piston and the cylinder is maintained at a uniform level, independent of engine conditions through a balancing of the pressure exerted upon the ring's surface and thereby allowing the contact pressure on the ring to be predetermined through the use of a preloaded expander ring.

  8. Physics of quantum rings

    International Nuclear Information System (INIS)

    Fomin, Vladimir M.

    2014-01-01

    Presents the new class of materials of quantum rings. Provides an elemental basis for low-cost high-performance devices promising for electronics, optoelectronics, spintronics and quantum information processing. Explains the physical properties of quantum rings to cover a gap in scientific literature. Presents the application of most advanced nanoengineering and nanocharacterization techniques. This book deals with a new class of materials, quantum rings. Innovative recent advances in experimental and theoretical physics of quantum rings are based on the most advanced state-of-the-art fabrication and characterization techniques as well as theoretical methods. The experimental efforts allow to obtain a new class of semiconductor quantum rings formed by capping self-organized quantum dots grown by molecular beam epitaxy. Novel optical and magnetic properties of quantum rings are associated with non-trivial topologies at the nanoscale. An adequate characterization of quantum rings is possible on the basis of modern characterization methods of nanostructures, such as Scanning Tunneling Microscopy. A high level of complexity is demonstrated to be needed for a dedicated theoretical model to adequately represent the specific features of quantum rings. The findings presented in this book contribute to develop low-cost high-performance electronic, spintronic, optoelectronic and information processing devices based on quantum rings.

  9. How does the blue-ringed octopus (Hapalochlaena lunulata) flash its blue rings?

    Science.gov (United States)

    Mäthger, Lydia M; Bell, George R R; Kuzirian, Alan M; Allen, Justine J; Hanlon, Roger T

    2012-11-01

    The blue-ringed octopus (Hapalochlaena lunulata), one of the world's most venomous animals, has long captivated and endangered a large audience: children playing at the beach, divers turning over rocks, and biologists researching neurotoxins. These small animals spend much of their time in hiding, showing effective camouflage patterns. When disturbed, the octopus will flash around 60 iridescent blue rings and, when strongly harassed, bite and deliver a neurotoxin that can kill a human. Here, we describe the flashing mechanism and optical properties of these rings. The rings contain physiologically inert multilayer reflectors, arranged to reflect blue-green light in a broad viewing direction. Dark pigmented chromatophores are found beneath and around each ring to enhance contrast. No chromatophores are above the ring; this is unusual for cephalopods, which typically use chromatophores to cover or spectrally modify iridescence. The fast flashes are achieved using muscles under direct neural control. The ring is hidden by contraction of muscles above the iridophores; relaxation of these muscles and contraction of muscles outside the ring expose the iridescence. This mechanism of producing iridescent signals has not previously been reported in cephalopods and we suggest that it is an exceptionally effective way to create a fast and conspicuous warning display.

  10. α-Skew π-McCoy Rings

    Directory of Open Access Journals (Sweden)

    Areej M. Abduldaim

    2013-01-01

    Full Text Available As a generalization of α-skew McCoy rings, we introduce the concept of α-skew π-McCoy rings, and we study the relationships with another two new generalizations, α-skew π1-McCoy rings and α-skew π2-McCoy rings, observing the relations with α-skew McCoy rings, π-McCoy rings, α-skew Armendariz rings, π-regular rings, and other kinds of rings. Also, we investigate conditions such that α-skew π1-McCoy rings imply α-skew π-McCoy rings and α-skew π2-McCoy rings. We show that in the case where R is a nonreduced ring, if R is 2-primal, then R is an α-skew π-McCoy ring. And, let R be a weak (α,δ-compatible ring; if R is an α-skew π1-McCoy ring, then R is α-skew π2-McCoy.

  11. VUV optical ring resonator for Duke storage ring free electron laser

    Energy Technology Data Exchange (ETDEWEB)

    Park, S.H.; Litvinenko, V.N.; Madey, J.M.J. [Duke Univ., Durham, NC (United States)] [and others

    1995-12-31

    The conceptual design of the multifaceted-mirror ring resonator for Duke storage ring VUV FEL is presented. The expected performance of the OK-4 FEL with ring resonator is described. We discuss in this paper our plans to study reflectivity of VUV mirrors and their resistivity to soft X-ray spontaneous radiation from OK-4 undulator.

  12. Black swans, power laws, and dragon-kings: Earthquakes, volcanic eruptions, landslides, wildfires, floods, and SOC models

    Science.gov (United States)

    Sachs, M. K.; Yoder, M. R.; Turcotte, D. L.; Rundle, J. B.; Malamud, B. D.

    2012-05-01

    Extreme events that change global society have been characterized as black swans. The frequency-size distributions of many natural phenomena are often well approximated by power-law (fractal) distributions. An important question is whether the probability of extreme events can be estimated by extrapolating the power-law distributions. Events that exceed these extrapolations have been characterized as dragon-kings. In this paper we consider extreme events for earthquakes, volcanic eruptions, wildfires, landslides and floods. We also consider the extreme event behavior of three models that exhibit self-organized criticality (SOC): the slider-block, forest-fire, and sand-pile models. Since extrapolations using power-laws are widely used in probabilistic hazard assessment, the occurrence of dragon-king events have important practical implications.

  13. Interaction Region Design for a Ring-Ring LHeC

    CERN Document Server

    Thompson, L N S; Bernard, N R; Fitterer, M; Holzer, B; Klein, M; Kostka, P

    2011-01-01

    tively low energy and moderately high intensity provides high luminosity TeV-scale e-p collisions at one of the LHC interaction points, running simultaneously with existing experiments. Two designs are studied; an electron ring situated in the LHC tunnel, and an electron linac. The focus of this paper is on the ring design. Designing an e-p machine presents interesting accelerator physics and design challenges, particularly when considering the interaction region. These include coupled optics, beam separation and unconventional mini-beta focusing schemes. Designs are constrained by an array of interdependent factors, including beam-beam interaction, detector dimensions and acceptance, luminosity and synchrotron radiation. Methods of addressing these complex issues are discussed. The current designs for the LHeC Ring-Ring interaction region and long straight section are presented and discussed, in the context of the project goals and design challenges encountered. Future developments and work are also discusse...

  14. Diagenetic history of the Swan Hills Simonette Oil Reservoir (Givetian-Frasnian), deep basin of west-central Alberta, Canada

    Energy Technology Data Exchange (ETDEWEB)

    Duggan, J.P.; Mountjoy, E.W. [McGill Univ., Montreal, PQ (Canada). Dept. of Earth and Planetary Sciences

    1997-05-01

    The geology and diagenetic history of the Swan Hills Simonette oil field of west-central Alberta basin was described. Present-day burial depth is 3900 m; formation temperature is 93 degrees C. Highest porosites (20 per cent) occur in dolostones of the lagoon, ref, and fore-reef depositional environments but limestones still retain porosities up to five per cent. Hydrocarbons are present in saddle dolomite fluid inclusions. Oxygen isotopes for replacement dolomites and late calcite suggest that the carbonate-precipitating fluids were derived from the Precambrian basement or Paleozoic clastics sourced from the basement. Faults may have acted as vertical conduits for fluid migration.

  15. Uniquely Strongly Clean Group Rings

    Institute of Scientific and Technical Information of China (English)

    WANG XIU-LAN

    2012-01-01

    A ring R is called clean if every element is the sum of an idempotent and a unit,and R is called uniquely strongly clean (USC for short) if every element is uniquely the sum of an idempotent and a unit that commute.In this article,some conditions on a ring R and a group G such that RG is clean are given.It is also shown that if G is a locally finite group,then the group ring RG is USC if and only if R is USC,and G is a 2-group.The left uniquely exchange group ring,as a middle ring of the uniquely clean ring and the USC ring,does not possess this property,and so does the uniquely exchange group ring.

  16. Acute Traumatic Swan Neck Deformity: A Case Report of the Oblique Retinacular Ligament Lesion.

    Science.gov (United States)

    Checcucci, Giuseppe; Biondi, Marco; Faccio, Marina; Zampetti, Piergiuseppe; Galeano, Mariarosaria; Ceruso, Massimo

    2017-09-01

    Swan neck deformity (SND) can be the manifestation of an acute trauma. We present a case report of a young basketball player with an acute traumatic SND determined by the single ulnar oblique retinacular ligament rupture. The patient caught a ball directly upon the tip of his right's hand middle finger into extension. He immediately presented a SND with impossibility to actively flex the proximal interphalangeal joint (PIPJ), while preserving active flexion and extension of the distal interphalangeal joint (DIPJ). Hyperextension of PIPJ was reducible with passive mobilization, thus allowing full passive range of motion. The SND was seen to be caused by the lesion of the ulnar oblique retinacular ligament (ORL) on its distal insertion, with consequent dorsomedial migration of the ulnar lateral band. The early surgical distal reinsertion of the ORL allowed the restoration of the original kinematics of the finger flexion-extension.

  17. Influence of ring growth rate on damage development in hot ring rolling

    NARCIS (Netherlands)

    Wang, C.; Geijselaers, H. J.M.; Omerspahic, E.; Recina, V.; van den Boogaard, A. H.

    2015-01-01

    As an incremental forming process of bulk metal, ring rolling provides a cost effective process route to manufacture seamless rings. In the production of hot rolled rings, defects such as porosity can sometimes be found in high alloyed steel, manufactured from ingots having macro-segregation. For

  18. Ring rotational speed trend analysis by FEM approach in a Ring Rolling process

    Science.gov (United States)

    Allegri, G.; Giorleo, L.; Ceretti, E.

    2018-05-01

    Ring Rolling is an advanced local incremental forming technology to fabricate directly precise seamless ring-shape parts with various dimensions and materials. In this process two different deformations occur in order to reduce the width and the height of a preform hollow ring; as results a diameter expansion is obtained. In order to guarantee a uniform deformation, the preform is forced toward the Driver Roll whose aim is to transmit the rotation to the ring. The ring rotational speed selection is fundamental because the higher is the speed the higher will be the axial symmetry of the deformation process. However, it is important to underline that the rotational speed will affect not only the final ring geometry but also the loads and energy needed to produce it. Despite this importance in industrial environment, usually, a constant value for the Driver Roll angular velocity is set so to result in a decreasing trend law for the ring rotational speed. The main risk due to this approach is not fulfilling the axial symmetric constrain (due to the diameter expansion) and to generate a high localized ring section deformation. In order to improve the knowledge about this topic in the present paper three different ring rotational speed trends (constant, linearly increasing and linearly decreasing) were investigated by FEM approach. Results were compared in terms of geometrical and dimensional analysis, loads and energies required.

  19. Mechanical improvement of metal reinforcement rings for a finite ring-shaped superconducting bulk

    Science.gov (United States)

    Huang, Chen-Guang; Zhou, You-He

    2018-03-01

    As a key technique, reinforcement of type-II superconducting bulks with metal rings can efficiently improve their mechanical properties to enhance the maximum trapped field. In this paper, we study the magnetostrictive and fracture behaviors of a finite superconducting ring bulk reinforced by three typical reinforcing structures composed of metal rings during the magnetizing process by means of the minimization of magnetic energy and the finite element method. After a field-dependent critical current density is adopted, the magnetostriction, pinning-induced stress, and crack tip stress intensity factor are calculated considering the demagnetization effects. The results show that the mechanical properties of the ring bulk are strongly dependent on the reinforcing structure and the material and geometrical parameters of the metal rings. Introducing the metal ring can significantly reduce the hoop stress, and the reduction effect by internal reinforcement is much improved relative to external reinforcement. By comparison, bilateral reinforcement seems to be the best candidate structure. Only when the metal rings have particular Young's modulus and radial thickness will they contribute to improve the mechanical properties the most. In addition, if an edge crack is pre-existing in the ring bulk, the presence of metal rings can effectively avoid crack propagation since it reduces the crack tip stress intensity factor by nearly one order of magnitude.

  20. Ring correlations in random networks.

    Science.gov (United States)

    Sadjadi, Mahdi; Thorpe, M F

    2016-12-01

    We examine the correlations between rings in random network glasses in two dimensions as a function of their separation. Initially, we use the topological separation (measured by the number of intervening rings), but this leads to pseudo-long-range correlations due to a lack of topological charge neutrality in the shells surrounding a central ring. This effect is associated with the noncircular nature of the shells. It is, therefore, necessary to use the geometrical distance between ring centers. Hence we find a generalization of the Aboav-Weaire law out to larger distances, with the correlations between rings decaying away when two rings are more than about three rings apart.

  1. Alpha - Skew Pi - Armendariz Rings

    Directory of Open Access Journals (Sweden)

    Areej M Abduldaim

    2018-03-01

    Full Text Available In this article we introduce a new concept called Alpha-skew Pi-Armendariz rings (Alpha - S Pi - ARas a generalization of the notion of Alpha-skew Armendariz rings.Another important goal behind studying this class of rings is to employ it in order to design a modern algorithm of an identification scheme according to the evolution of using modern algebra in the applications of the field of cryptography.We investigate general properties of this concept and give examples for illustration. Furthermore, this paperstudy the relationship between this concept and some previous notions related to Alpha-skew Armendariz rings. It clearly presents that every weak Alpha-skew Armendariz ring is Alpha-skew Pi-Armendariz (Alpha-S Pi-AR. Also, thisarticle showsthat the concepts of Alpha-skew Armendariz rings and Alpha-skew Pi- Armendariz rings are equivalent in case R is 2-primal and semiprime ring.Moreover, this paper proves for a semicommutative Alpha-compatible ringR that if R[x;Alpha] is nil-Armendariz, thenR is an Alpha-S Pi-AR. In addition, if R is an Alpha - S Pi -AR, 2-primal and semiprime ring, then N(R[x;Alpha]=N(R[x;Alpha]. Finally, we look forwardthat Alpha-skew Pi-Armendariz rings (Alpha-S Pi-ARbe more effect (due to their properties in the field of cryptography than Pi-Armendariz rings, weak Armendariz rings and others.For these properties and characterizations of the introduced concept Alpha-S Pi-AR, we aspire to design a novel algorithm of an identification scheme.

  2. Plasma-ring, fast-opening switch

    International Nuclear Information System (INIS)

    Hartman, C.W.; Eddleman, J.; Hammer, J.H.

    1986-01-01

    The authors discuss a fast-opening switch concept based on magnetically confined plasma rings, PROS (for Plasma Ring Opening Switch). In PROS, the plasma ring, confined by Bθ /sub and B/poloidal /sub fields of a compact torus, provide a low mass, localized conduction path between coaxial electrodes. To operate the switch, driver current is passed across the electrodes through the ring, storing inductive energy in external inductance and between the electrodes on the driver side of the ring. The ring is accelerated away from the driver by the field of the driver current and passes over a load gap transferring the current to the load. The authors distinguish two configurations in PROS, straight PROS where the electrodes are coaxial cylinders, and cone PROS with conical electrodes. In straight PROS ring acceleration takes place during the inductive store period as in foil switches, but with the localized ring providing the current path. Increased performance is predicted for the cone PROS (see figure) which employs compression of the ring in the cone during the inductive store period. Here, the B/θ /sub field of the driver forces the ring towards the apex of the cone but the force is in near balance with the opposing component of the radial equilibrium force of the ring along the cone. As a result, the ring undergoes a slow, quasistatic compression limited only by resistive decay of the ring field. Slow compression allows inductive storage with low-power drivers (homopoloar, magneto cumulative generators, high C-low V capacitor banks, etc.). Near the apex of the cone, near peak compression, the ring is allowed to enter a straight coaxial section where, because of low-mass, it rapidly accelerates to high velocity and crosses the load gap

  3. Fusion Rings for Quantum Groups

    DEFF Research Database (Denmark)

    Andersen, Henning Haahr; Stroppel, Catharina

    2014-01-01

    We study the fusion rings of tilting modules for a quantum group at a root of unity modulo the tensor ideal of negligible tilting modules. We identify them in type A with the combinatorial rings from Korff, C., Stroppel, C.: The sl(ˆn)k-WZNW fusion ring: a combinato-rial construction...... and a realisation as quotient of quantum cohomology. Adv. Math. 225(1), 200–268, (2010) and give a similar description of the sp2n-fusion ring in terms of non-commutative symmetric functions. Moreover we give a presentation of all fusion rings in classical types as quotients of polynomial rings. Finally we also...... compute the fusion rings for type G2....

  4. The LSU Electron Storage Ring, the first commercially-built storage ring

    International Nuclear Information System (INIS)

    Sah, R.

    1990-01-01

    The Brobeck Division of Maxwell Laboratories, Inc., is building the first industrially-produced storage ring. It will be located at Louisiana State University (LSU) at the Center for Advanced Microstructures and Devices (CAMD) in Baton Rouge. The purpose of this electron storage ring is to provide intense beams of x-rays to advance the state-of-the-art in lithography and to permit research in a broad area. This facility consists of a 1.2 GeV, 400 mA electron storage ring with a 200 MeV linac injector. The magnet lattice is a Chasman-Green design (double-bend achromat), and the ring circumference is 55.2 meters. There are four 3.0 meter, dispersion-free straight sections, one for injection, one for the 500 MHz RF cavity, and two for possible future insertion devices. The storge ring construction project is in the detailed-design stage, and many systems are in the initial stages of fabrication. 4 figs., 1 tab

  5. Fusion rings and fusion ideals

    DEFF Research Database (Denmark)

    Andersen, Troels Bak

    by the so-called fusion ideals. The fusion rings of Wess-Zumino-Witten models have been widely studied and are well understood in terms of precise combinatorial descriptions and explicit generating sets of the fusion ideals. They also appear in another, more general, setting via tilting modules for quantum......This dissertation investigates fusion rings, which are Grothendieck groups of rigid, monoidal, semisimple, abelian categories. Special interest is in rational fusion rings, i.e., fusion rings which admit a finite basis, for as commutative rings they may be presented as quotients of polynomial rings...

  6. Temporal pattern in the bloom-forming macroalgae Chaetomorpha linum and Ulva pertusa in seagrass beds, Swan Lake lagoon, North China

    International Nuclear Information System (INIS)

    Zhang, Xiaomei; Zhou, Yi; Liu, Peng; Wang, Feng; Liu, Bingjian; Liu, Xujia; Xu, Qiang; Yang, Hongsheng

    2014-01-01

    Highlights: • We conducted an annual survey of bloom-forming macroalgae in a lagoon. • C. linum biomass reached 1712 ± 780 g DW m −2 at the northern part of the lagoon. • Macroalgae δ 15 N values indicated a land-based source of N enrichment to the blooms. • High nutrient concentrations near the river mouth supported the blooms. • C. linum blooms induced the loss of seagrasses and benthic filter feeders. - Abstract: Seagrasses that are distributed over a large area of the Swan Lake, Weihai, China, support a productive ecosystem. In recent years, however, frequent macroalgal blooms have changed the ecosystem structure and threatened the seagrasses. To understand the bloom-forming macroalgae we conducted a yearly field survey of Swan Lake. Results indicated that the macroalgae Chaetomorpha linum and Ulva pertusa both exhibited a much higher productivity and attained a greater maximum biomass (of 1712 ± 780 g DW m −2 and 1511 ± 555 g DW m −2 , respectively) than was the case for the seagrasses. The mean annual atomic ratios of C/N, C/P and N/P in C. linum were 14.31 ± 4.45, 402.82 ± 130.25, and 28.12 ± 2.08, respectively. The δ 15 N values (11.09 ± 0.91‰ for C. linum; 9.27 ± 2.83‰ for U. pertusa) indicated a land-based source of N enrichment to the macroalgal blooms. High concentrations of nitrogen and phosphorus in the lagoon, particularly near the river mouth, supported the blooms

  7. Evaluation of ring impedance of the Photon Factory storage ring

    International Nuclear Information System (INIS)

    Kiuchi, T.; Izawa, M.; Tokumoto, S.; Hori, Y.; Sakanaka, S.; Kobayashi, M.; Kobayakawa, H.

    1992-05-01

    The loss parameters of the ducts in the Photon Factory (PF) storage ring were evaluated using the wire method and the code TBCI. Both the measurement and the calculation were done for a different bunch length (σ) ranging from 23 to 80 ps. The PF ring impedance was estimated to be |Z/n|=3.2 Ω using the broadband impedance model. The major contribution to the impedance comes from the bellows and the gate valve sections. Improvements of these components will lower the ring impedance by half. (author)

  8. Tree Rings: Timekeepers of the Past.

    Science.gov (United States)

    Phipps, R. L.; McGowan, J.

    One of a series of general interest publications on science issues, this booklet describes the uses of tree rings in historical and biological recordkeeping. Separate sections cover the following topics: dating of tree rings, dating with tree rings, tree ring formation, tree ring identification, sample collections, tree ring cross dating, tree…

  9. Some Aspects of Ring Theory

    CERN Document Server

    Herstein, IN

    2011-01-01

    S. Amitsur: Associative rings with identities.- I.N. Herstein: Topics in ring theory.- N. Jacobson: Representation theory of Jordan algebras.- I. Kaplansky: The theory of homological dimension.- D. Buchsbaum: Complexes in local ring theory.- P.H. Cohn: Two topics in ring theory.- A.W. Goldie: Non-commutative localisation.

  10. The Six Swans and the Girl Some considerations about the salvation in Simone Weil

    Directory of Open Access Journals (Sweden)

    Maria Clara Lucchetti Bingemer

    2015-04-01

    Full Text Available This paper aims to show the connection that Simone Weil´s thought has always had with the literature, specially with the fables and tales. Fables and tales have true insights of the Truth coming from the depths of humanity unconscious and after that become true believed and appropriate by the cultures and civilizations. Among these fables and tales, there is one that has fascinated since childhood Simone: The six swans by Grimm.  In it,Simone, an agnostic and still knowing nothing of Christianity,describes the role of the girl who has saved his brothers from a spell. This tale, certainly has prepared the meeting of Simone with Christianity, as well as reading she did the Christian narrative of salvation wich she has lived herself.Keywords: Simone Weil; Grimm Tales; Theology and Literature.

  11. An investigation into the Swan Island Honduras collecting event of Tiaporus fuliginosus Cope (Reptilia: Teiidae) and its systematic status

    Science.gov (United States)

    McCranie, James R.; Gotte, Steve W.

    2015-01-01

    Confusion exists in the literature concerning the collecting event of the teiid lizard Tiaporus fuliginosus. We investigated the literature and documents stored at the Smithsonian Institution Archives involving the collector of those specimens in an effort to resolve that confusion. We conclude that the type series was collected on the Swan Islands of Honduras by Charles H. Townsend during 1887. We also provide a redescription of that nominal form and show that it is a valid species that should be called Ameiva fuliginosa. We also examined the type series of A. panchlora from Old Providence, Colombia and confirm that its 1950 placement as a junior synonym of A. fuliginosa is correct.

  12. Improving the Accuracy of Laplacian Estimation with Novel Variable Inter-Ring Distances Concentric Ring Electrodes

    Directory of Open Access Journals (Sweden)

    Oleksandr Makeyev

    2016-06-01

    Full Text Available Noninvasive concentric ring electrodes are a promising alternative to conventional disc electrodes. Currently, the superiority of tripolar concentric ring electrodes over disc electrodes, in particular, in accuracy of Laplacian estimation, has been demonstrated in a range of applications. In our recent work, we have shown that accuracy of Laplacian estimation can be improved with multipolar concentric ring electrodes using a general approach to estimation of the Laplacian for an (n + 1-polar electrode with n rings using the (4n + 1-point method for n ≥ 2. This paper takes the next step toward further improving the Laplacian estimate by proposing novel variable inter-ring distances concentric ring electrodes. Derived using a modified (4n + 1-point method, linearly increasing and decreasing inter-ring distances tripolar (n = 2 and quadripolar (n = 3 electrode configurations are compared to their constant inter-ring distances counterparts. Finite element method modeling and analytic results are consistent and suggest that increasing inter-ring distances electrode configurations may decrease the truncation error resulting in more accurate Laplacian estimates compared to respective constant inter-ring distances configurations. For currently used tripolar electrode configuration, the truncation error may be decreased more than two-fold, while for the quadripolar configuration more than a six-fold decrease is expected.

  13. Improving the Accuracy of Laplacian Estimation with Novel Variable Inter-Ring Distances Concentric Ring Electrodes

    Science.gov (United States)

    Makeyev, Oleksandr; Besio, Walter G.

    2016-01-01

    Noninvasive concentric ring electrodes are a promising alternative to conventional disc electrodes. Currently, the superiority of tripolar concentric ring electrodes over disc electrodes, in particular, in accuracy of Laplacian estimation, has been demonstrated in a range of applications. In our recent work, we have shown that accuracy of Laplacian estimation can be improved with multipolar concentric ring electrodes using a general approach to estimation of the Laplacian for an (n + 1)-polar electrode with n rings using the (4n + 1)-point method for n ≥ 2. This paper takes the next step toward further improving the Laplacian estimate by proposing novel variable inter-ring distances concentric ring electrodes. Derived using a modified (4n + 1)-point method, linearly increasing and decreasing inter-ring distances tripolar (n = 2) and quadripolar (n = 3) electrode configurations are compared to their constant inter-ring distances counterparts. Finite element method modeling and analytic results are consistent and suggest that increasing inter-ring distances electrode configurations may decrease the truncation error resulting in more accurate Laplacian estimates compared to respective constant inter-ring distances configurations. For currently used tripolar electrode configuration, the truncation error may be decreased more than two-fold, while for the quadripolar configuration more than a six-fold decrease is expected. PMID:27294933

  14. Disease patterns in the Detroit Zoo: a study of the avian population from 1973 through 1983.

    Science.gov (United States)

    Kaneene, J B; Taylor, R F; Sikarskie, J G; Meyer, T J; Richter, N A

    1985-12-01

    A retrospective study was conducted to evaluate disease patterns in birds at the Detroit Zoo from 1973 through 1983. Data were derived from the zoo's medical and animal census records; the mean (+/- SD) population of birds during the study period was 469 +/- 42. Overall annual morbidity rates were 12.5% to 21.5%, with spring months having the highest morbidity rates. Annual mortality rates were 3.1% to 15.2%; 23.9% of the deaths were caused by microbial agents (particularly Erysipelothrix rhusiopathiae, hemolytic Escherichia coli, Salmonella spp, Aeromonas spp and Proteus spp), 15.4% by trauma, and 42.5% by nondetermined causes. The mute swan (Cygnus olor), mallard duck (Anas platyrhynchos), common gallinule (Gallinula chloropus), common rhea (Rhea americana), and red-billed hornbill (Tockus erythrorhynchus) were the 5 species most frequently affected of the 1,032 deaths from 1973 through 1983. The most frequently isolated parasites were Microtetramere spp, coccidian species, Diplotriaena spp, and Trichomonia spp.

  15. Are predictions of cancer response to targeted drugs, based on effects in unrelated tissues, the 'Black Swan' events?

    Science.gov (United States)

    Kurbel, Beatrica; Golem, Ante Zvonimir; Kurbel, Sven

    2015-01-01

    Adverse effects of targeted drugs on normal tissues can predict the cancer response. Rash correlates with efficacy of erlotinib, cetuximab and gefitinib and onset of arterial hypertension with response to bevacizumab, sunitinib, axitinib and sorafenib, possible examples of 'Black Swan' events, unexpected scientific observations, as described by Karl Popper in 1935. The proposition is that our patients have individual intrinsic variants of cell growth control, important for tumor response and adverse effects on tumor-unrelated tissue. This means that the lack of predictive side effects in healthy tissue is linked with poor results of tumor therapy when tumor resistance is caused by mechanisms that protect all cells of that patient from the targeted drug effects.

  16. Radar imaging of Saturn's rings

    Science.gov (United States)

    Nicholson, Philip D.; French, Richard G.; Campbell, Donald B.; Margot, Jean-Luc; Nolan, Michael C.; Black, Gregory J.; Salo, Heikki J.

    2005-09-01

    We present delay-Doppler images of Saturn's rings based on radar observations made at Arecibo Observatory between 1999 and 2003, at a wavelength of 12.6 cm and at ring opening angles of 20.1°⩽|B|⩽26.7°. The average radar cross-section of the A ring is ˜77% relative to that of the B ring, while a stringent upper limit of 3% is placed on the cross-section of the C ring and 9% on that of the Cassini Division. These results are consistent with those obtained by Ostro et al. [1982, Icarus 49, 367-381] from radar observations at |B|=21.4°, but provide higher resolution maps of the rings' reflectivity profile. The average cross-section of the A and B rings, normalized by their projected unblocked area, is found to have decreased from 1.25±0.31 to 0.74±0.19 as the rings have opened up, while the circular polarization ratio has increased from 0.64±0.06 to 0.77±0.06. The steep decrease in cross-section is at variance with previous radar measurements [Ostro et al., 1980, Icarus 41, 381-388], and neither this nor the polarization variations are easily understood within the framework of either classical, many-particle-thick or monolayer ring models. One possible explanation involves vertical size segregation in the rings, whereby observations at larger elevation angles which see deeper into the rings preferentially see the larger particles concentrated near the rings' mid-plane. These larger particles may be less reflective and/or rougher and thus more depolarizing than the smaller ones. Images from all four years show a strong m=2 azimuthal asymmetry in the reflectivity of the A ring, with an amplitude of ±20% and minima at longitudes of 67±4° and 247±4° from the sub-Earth point. We attribute the asymmetry to the presence of gravitational wakes in the A ring as invoked by Colombo et al. [1976, Nature 264, 344-345] to explain the similar asymmetry long seen at optical wavelengths. A simple radiative transfer model suggests that the enhancement of the azimuthal

  17. Study of improvement in 1st ring`s gas-seal; Top ring no gas seal seino kojo no kento

    Energy Technology Data Exchange (ETDEWEB)

    Ando, H; Tateishi, Y; Fujimura, K; Hitosugi, H [Nippon Piston Ring Co. Ltd., Tokyo (Japan)

    1997-10-01

    The authors studied the effect of an angle of 1st ring twist on the amount of blow-by concerning higher speed/higher output engines for motorcycles. As a result, the authors found the twist made the ring restrained in a ring groove of piston , and confirmed its suitable range for blow-by. By means of the developed optimization method, the authors have achieved significant reduction in blow-by at high engine speed. 1 ref., 9 figs., 2 tabs.

  18. Viscosity of ring polymer melts

    KAUST Repository

    Pasquino, Rossana

    2013-10-15

    We have measured the linear rheology of critically purified ring polyisoprenes, polystyrenes, and polyethyleneoxides of different molar masses. The ratio of the zero-shear viscosities of linear polymer melts η0,linear to their ring counterparts η0,ring at isofrictional conditions is discussed as a function of the number of entanglements Z. In the unentangled regime η0,linear/η 0,ring is virtually constant, consistent with the earlier data, atomistic simulations, and the theoretical expectation η0,linear/ η0,ring = 2. In the entanglement regime, the Z-dependence of ring viscosity is much weaker than that of linear polymers, in qualitative agreement with predictions from scaling theory and simulations. The power-law extracted from the available experimental data in the rather limited range 1 < Z < 20, η0,linear/η0,ring ∼ Z 1.2±0.3, is weaker than the scaling prediction (η0,linear/η0,ring ∼ Z 1.6±0.3) and the simulations (η0,linear/ η0,ring ∼ Z2.0±0.3). Nevertheless, the present collection of state-of-the-art experimental data unambiguously demonstrates that rings exhibit a universal trend clearly departing from that of their linear counterparts, and hence it represents a major step toward resolving a 30-year-old problem. © 2013 American Chemical Society.

  19. Viscosity of ring polymer melts

    KAUST Repository

    Pasquino, Rossana; Vasilakopoulos, Thodoris C.; Jeong, Youncheol; Lee, Hyojoon; Rogers, Simon A.; Sakellariou, Georgios; Allgaier, Jü rgen B.; Takano, Atsushi; Brá s, Ana Rita E; Chang, Taihyun; Gooß en, Sebastian; Pyckhout-Hintzen, Wim; Wischnewski, Andreas; Hadjichristidis, Nikolaos; Richter, Dieter R.; Rubinstein, Michael H.; Vlassopoulos, Dimitris

    2013-01-01

    We have measured the linear rheology of critically purified ring polyisoprenes, polystyrenes, and polyethyleneoxides of different molar masses. The ratio of the zero-shear viscosities of linear polymer melts η0,linear to their ring counterparts η0,ring at isofrictional conditions is discussed as a function of the number of entanglements Z. In the unentangled regime η0,linear/η 0,ring is virtually constant, consistent with the earlier data, atomistic simulations, and the theoretical expectation η0,linear/ η0,ring = 2. In the entanglement regime, the Z-dependence of ring viscosity is much weaker than that of linear polymers, in qualitative agreement with predictions from scaling theory and simulations. The power-law extracted from the available experimental data in the rather limited range 1 < Z < 20, η0,linear/η0,ring ∼ Z 1.2±0.3, is weaker than the scaling prediction (η0,linear/η0,ring ∼ Z 1.6±0.3) and the simulations (η0,linear/ η0,ring ∼ Z2.0±0.3). Nevertheless, the present collection of state-of-the-art experimental data unambiguously demonstrates that rings exhibit a universal trend clearly departing from that of their linear counterparts, and hence it represents a major step toward resolving a 30-year-old problem. © 2013 American Chemical Society.

  20. ring og refleksion

    DEFF Research Database (Denmark)

    Wahlgren, B.; Rattleff, Pernille; Høyrup, S.

    State of the art inden for forskning om læring på arbejdspladsen samt gennemgang af læringsteori og refleksionsbegrebet hos Dewey, Dreyfus, Schön, Argyris, Kolb, Jarvis, Mezirow og Brookfield. Afsluttes med diskussion af syntetiseret model for læring på arbejdspladsen.......State of the art inden for forskning om læring på arbejdspladsen samt gennemgang af læringsteori og refleksionsbegrebet hos Dewey, Dreyfus, Schön, Argyris, Kolb, Jarvis, Mezirow og Brookfield. Afsluttes med diskussion af syntetiseret model for læring på arbejdspladsen....

  1. Birth Control Ring

    Science.gov (United States)

    ... Health Food & Fitness Diseases & Conditions Infections Drugs & Alcohol School & Jobs Sports Expert Answers (Q&A) Staying Safe Videos for Educators Search English Español Birth Control Ring KidsHealth / For Teens / Birth Control Ring What's ...

  2. From coffee ring to spherulites ring of poly(ethylene oxide) film from drying droplet

    Science.gov (United States)

    Hu, Yinchun; Zhang, Xuerong; Qiu, Maibo; Wei, Yan; Zhou, Qiong; Huang, Di

    2018-03-01

    We discuss how the "spherulites ring" morphology and "coffee ring" profile of PEO film formed by the drying droplet at glass substrate with different heating rate. Upon increasing the heating rate of substrate, it is found that deposited PEO film from drying droplet shows the unusually observed "coffee ring" profile and "spherulites ring" morphology. The main mechanism for this phenomenon is proposed to be an enhanced Marangoni convection which is induced by the increased solute concentration gradient and reduced viscous force above 70 °C. A simple formation mechanism of the unusually observed "coffee ring" profile and "spherulites ring" morphology is proposed. These findings can be exploited to trace the center of Marangoni convection, with potential applications in designing the spherulite patterns of crystalline polymer films in ink-jet printing and self-assembly fields.

  3. Development of an updated phytoestrogen database for use with the SWAN food frequency questionnaire: intakes and food sources in a community-based, multiethnic cohort study.

    Science.gov (United States)

    Huang, Mei-Hua; Norris, Jean; Han, Weijuan; Block, Torin; Gold, Ellen; Crawford, Sybil; Greendale, Gail A

    2012-01-01

    Phytoestrogens, heterocyclic phenols found in plants, may benefit several health outcomes. However, epidemiologic studies of the health effects of dietary phytoestrogens have yielded mixed results, in part due to challenges inherent in estimating dietary intakes. The goal of this study was to improve the estimates of dietary phytoestrogen consumption using a modified Block Food Frequency Questionnaire (FFQ), a 137-item FFQ created for the Study of Women's Health Across the Nation (SWAN) in 1994. To expand the database of sources from which phytonutrient intakes were computed, we conducted a comprehensive PubMed/Medline search covering January 1994 through September 2008. The expanded database included 4 isoflavones, coumestrol, and 4 lignans. The new database estimated isoflavone content of 105 food items (76.6%) vs. 14 (10.2%) in the 1994 version and computed coumestrol content of 52 food items (38.0%), compared to 1 (0.7%) in the original version. Newly added were lignans; values for 104 FFQ food items (75.9%) were calculated. In addition, we report here the phytonutrient intakes for each racial and language group in the SWAN sample and present major food sources from which the phytonutrients came. This enhanced ascertainment of phytoestrogens will permit improved studies of their health effects.

  4. Systematic Search for Rings around Kepler Planet Candidates: Constraints on Ring Size and Occurrence Rate

    Science.gov (United States)

    Aizawa, Masataka; Masuda, Kento; Kawahara, Hajime; Suto, Yasushi

    2018-05-01

    We perform a systematic search for rings around 168 Kepler planet candidates with sufficient signal-to-noise ratios that are selected from all of the short-cadence data. We fit ringed and ringless models to their light curves and compare the fitting results to search for the signatures of planetary rings. First, we identify 29 tentative systems, for which the ringed models exhibit statistically significant improvement over the ringless models. The light curves of those systems are individually examined, but we are not able to identify any candidate that indicates evidence for rings. In turn, we find several mechanisms of false positives that would produce ringlike signals, and the null detection enables us to place upper limits on the size of the rings. Furthermore, assuming the tidal alignment between axes of the planetary rings and orbits, we conclude that the occurrence rate of rings larger than twice the planetary radius is less than 15%. Even though the majority of our targets are short-period planets, our null detection provides statistical and quantitative constraints on largely uncertain theoretical models of the origin, formation, and evolution of planetary rings.

  5. Structure and dynamics of ringed galaxies

    International Nuclear Information System (INIS)

    Buta, R.J.

    1984-01-01

    In many spiral and SO galaxies, single or multiple ring structures are visible in the disk. These inner rings (r), outer rings (R), and nuclear rings (nr) were investigated by means of morphology, photometry, and spectroscopy in order to provide basic data on a long neglected phenomenon. The metric properties of each ring are investigated and found to correlate with the structure of the parent galaxy. When properly calibrated, inner rings in barred (SB) systems can be used as geometric extragalactic distance indicators to distances in excess of 100 Mpc. Other statistics are presented that confirm previous indications that the rings have preferred shapes, relative sizes, and orientations with respect to bars. A survey is made of the less homogeneous non-barred (SA) ringed systems, and the causes of the inhomogeneity are isolated. It is shown that rings can be identified in multiple-ring SA systems that are exactly analogous to those in barred spirals

  6. Multiplicative Structure and Hecke Rings of Generator Matrices for Codes over Quotient Rings of Euclidean Domains

    Directory of Open Access Journals (Sweden)

    Hajime Matsui

    2017-12-01

    Full Text Available In this study, we consider codes over Euclidean domains modulo their ideals. In the first half of the study, we deal with arbitrary Euclidean domains. We show that the product of generator matrices of codes over the rings mod a and mod b produces generator matrices of all codes over the ring mod a b , i.e., this correspondence is onto. Moreover, we show that if a and b are coprime, then this correspondence is one-to-one, i.e., there exist unique codes over the rings mod a and mod b that produce any given code over the ring mod a b through the product of their generator matrices. In the second half of the study, we focus on the typical Euclidean domains such as the rational integer ring, one-variable polynomial rings, rings of Gaussian and Eisenstein integers, p-adic integer rings and rings of one-variable formal power series. We define the reduced generator matrices of codes over Euclidean domains modulo their ideals and show their uniqueness. Finally, we apply our theory of reduced generator matrices to the Hecke rings of matrices over these Euclidean domains.

  7. INTEGRAÇÃO DE MODELAGEM NUMÉRICA (SWAN E DADOS DE CAMPO NA DETERMINAÇÃO DO CLIMA DE ONDAS NO LITORAL SETENTRIONAL DO RIO GRANDE DO NORTE

    Directory of Open Access Journals (Sweden)

    Maria de Fatima Alves de Matos

    2017-05-01

    Full Text Available Este artigo apresenta os resultados da aplicação do modelo numérico Simulating WAves Nearshore (SWAN com análises comparativas das medidas obtidas a partir dos resultados de modelagem e de medições durante as campanhas de campo em 2010 e 2012 no Litoral Setentrional do Rio Grande do Norte (NE do Brasil. O objetivo principal do presente estudo foi aplicar e validar o modelo numérico SWAN na determinação do clima de ondas, avaliar seus pontos fortes e limitações para a região de interesse. Os dados de campo realizados em dois pontos próximo da costa em profundidades de 3 m (PT_1 e 6 m (PT_2 por meio do uso de dois adcp: AWAC e AQUADOPP. Os dados adquiridos com estes equipamentos foram processados e permitiram a realização de análises espectrais de altura significativa, HS (m, período médio, Tmed (s, e direção média, DIR (º. Para a implementação do modelo SWAN foram empregados para as condições de contorno os dados de agitação a partir do modelo de 3ª geração de escala oceânica Wavewatch III. Para o refinamento e aplicabilidade do modelo, foram introduzidos dados de ventos e maré locais, corrigidos com base no Manual de Engenharia Costeira (CEM, permitindo assim, melhor ajuste dos resultados da modelagem. O domínio de cálculo foi referenciado para as dimensões da carta náutica 720, com três malhas regulares de diferentes dimensões e resolução: externa, intermediária e interna, sendo esta última, utilizada para fornecer os parâmetros de propagação da onda ao longo da costa. As configurações usadas para o SWAN foram as padrões em modo estacionário, com as formulações KOMEN, a dissipação devido à rebentação induzida pelo fundo com atrito de fundo usando a formulação JONSWAP com coeficiente de atrito С = 0.015m2s-3 em condições wind sea, e a formulação whitecapping ou excesso de declividade, as interações entre tríades de ondas e interações onda-onda quádrupla. As estat

  8. Binomial Rings: Axiomatisation, Transfer and Classification

    OpenAIRE

    Xantcha, Qimh Richey

    2011-01-01

    Hall's binomial rings, rings with binomial coefficients, are given an axiomatisation and proved identical to the numerical rings studied by Ekedahl. The Binomial Transfer Principle is established, enabling combinatorial proofs of algebraical identities. The finitely generated binomial rings are completely classified. An application to modules over binomial rings is given.

  9. AN N-BODY INTEGRATOR FOR GRAVITATING PLANETARY RINGS, AND THE OUTER EDGE OF SATURN'S B RING

    International Nuclear Information System (INIS)

    Hahn, Joseph M.; Spitale, Joseph N.

    2013-01-01

    A new symplectic N-body integrator is introduced, one designed to calculate the global 360° evolution of a self-gravitating planetary ring that is in orbit about an oblate planet. This freely available code is called epi i nt, and it is distinct from other such codes in its use of streamlines to calculate the effects of ring self-gravity. The great advantage of this approach is that the perturbing forces arise from smooth wires of ring matter rather than discreet particles, so there is very little gravitational scattering and so only a modest number of particles are needed to simulate, say, the scalloped edge of a resonantly confined ring or the propagation of spiral density waves. The code is applied to the outer edge of Saturn's B ring, and a comparison of Cassini measurements of the ring's forced response to simulations of Mimas's resonant perturbations reveals that the B ring's surface density at its outer edge is σ 0 = 195 ± 60 g cm –2 , which, if the same everywhere across the ring, would mean that the B ring's mass is about 90% of Mimas's mass. Cassini observations show that the B ring-edge has several free normal modes, which are long-lived disturbances of the ring-edge that are not driven by any known satellite resonances. Although the mechanism that excites or sustains these normal modes is unknown, we can plant such a disturbance at a simulated ring's edge and find that these modes persist without any damping for more than ∼10 5 orbits or ∼100 yr despite the simulated ring's viscosity ν s = 100 cm 2 s –1 . These simulations also indicate that impulsive disturbances at a ring can excite long-lived normal modes, which suggests that an impact in the recent past by perhaps a cloud of cometary debris might have excited these disturbances, which are quite common to many of Saturn's sharp-edged rings

  10. Galactic rings revisited - I. CVRHS classifications of 3962 ringed galaxies from the Galaxy Zoo 2 Database

    Science.gov (United States)

    Buta, Ronald J.

    2017-11-01

    Rings are important and characteristic features of disc-shaped galaxies. This paper is the first in a series that re-visits galactic rings with the goals of further understanding the nature of the features and for examining their role in the secular evolution of galaxy structure. The series begins with a new sample of 3962 galaxies drawn from the Galaxy Zoo 2 citizen science data base, selected because zoo volunteers recognized a ring-shaped pattern in the morphology as seen in Sloan Digital Sky Survey colour images. The galaxies are classified within the framework of the Comprehensive de Vaucouleurs revised Hubble-Sandage system. It is found that zoo volunteers cued on the same kinds of ring-like features that were recognized in the 1995 Catalogue of Southern Ringed Galaxies. This paper presents the full catalogue of morphological classifications, comparisons with other sources of classifications and some histograms designed mainly to highlight the content of the catalogue. The advantages of the sample are its large size and the generally good quality of the images; the main disadvantage is the low physical resolution that limits the detectability of linearly small rings such as nuclear rings. The catalogue includes mainly inner and outer disc rings and lenses. Cataclysmic (`encounter-driven') rings (such as ring and polar ring galaxies) are recognized in less than 1 per cent of the sample.

  11. Quantum Fourier Transform Over Galois Rings

    OpenAIRE

    Zhang, Yong

    2009-01-01

    Galois rings are regarded as "building blocks" of a finite commutative ring with identity. There have been many papers on classical error correction codes over Galois rings published. As an important warm-up before exploring quantum algorithms and quantum error correction codes over Galois rings, we study the quantum Fourier transform (QFT) over Galois rings and prove it can be efficiently preformed on a quantum computer. The properties of the QFT over Galois rings lead to the quantum algorit...

  12. Sexual functioning and practices in a multi-ethnic study of midlife women: baseline results from SWAN.

    Science.gov (United States)

    Cain, Virginia S; Johannes, Catherine B; Avis, Nancy E; Mohr, Beth; Schocken, Miriam; Skurnick, Joan; Ory, Marcia

    2003-08-01

    This study examined the sexual practices and function of midlife women by ethnicity (African American, Caucasian, Chinese, Hispanic, Japanese) and menopausal status. Sexual behavior was compared in 3,262 women in the baseline cohort of SWAN. Participants were 42 to 52 years old, premenopausal or early perimenopausal, and not hysterectomized or using hormones. Analysis used multivariate proportional odds regression. In our sample, 79% had engaged in sex with a partner in the last 6 months, and a third considered sex to be very important. Common reasons for no sex (n = 676) were lack of partner (67%), lack of interest (33%), and fatigue (16%). Compared with Caucasians, Japanese and Chinese women were less likely, and African Americans more likely, to report sex as very important (p practices. Perimenopause status was associated only with higher frequencies of masturbation and pain during intercourse.

  13. Novel manifestations of the Aharonov-Bohm effect in quantum rings and Moebius rings

    International Nuclear Information System (INIS)

    Fomin, Vladimir M.

    2013-01-01

    - An overview is given on the recent experimental and theoretical advancements in studies of novel manifestations of the Aharonov-Bohm quantum-interference effect for excitons confined to self assembled quantum rings and other semiconductor nanostructures with ring-like states of charge carriers as well as for electrons in Moebius rings at the micro- and nanoscale. The exciton Aharonov-Bohm effect can be effectively controlled by an out-of-plane magnetic field, a vertical electric field, a spin disorder. A 'delocalization-to-localization' transition for the electron ground state occurs in a Moebius ring as it is made more inhomogeneous. (authors)

  14. Ring closure in actin polymers

    Energy Technology Data Exchange (ETDEWEB)

    Sinha, Supurna, E-mail: supurna@rri.res.in [Raman Research Institute, Bangalore 560080 (India); Chattopadhyay, Sebanti [Doon University, Dehradun 248001 (India)

    2017-03-18

    We present an analysis for the ring closure probability of semiflexible polymers within the pure bend Worm Like Chain (WLC) model. The ring closure probability predicted from our analysis can be tested against fluorescent actin cyclization experiments. We also discuss the effect of ring closure on bend angle fluctuations in actin polymers. - Highlights: • Ring closure of biopolymers. • Worm like chain model. • Predictions for experiments.

  15. On P-coherent endomorphism rings

    Indian Academy of Sciences (India)

    A ring is called right -coherent if every principal right ideal is finitely presented. Let M R be a right -module. We study the -coherence of the endomorphism ring of M R . It is shown that is a right -coherent ring if and only if every endomorphism of M R has a pseudokernel in add M R ; S is a left -coherent ring if and ...

  16. Identification of Two novel reassortant avian influenza a (H5N6) viruses in whooper swans in Korea, 2016.

    Science.gov (United States)

    Jeong, Jipseol; Woo, Chanjin; Ip, Hon S; An, Injung; Kim, Youngsik; Lee, Kwanghee; Jo, Seong-Deok; Son, Kidong; Lee, Saemi; Oem, Jae-Ku; Wang, Seung-Jun; Kim, Yongkwan; Shin, Jeonghwa; Sleeman, Jonathan; Jheong, Weonhwa

    2017-03-21

    On November 20, 2016 two novel strains of H5N6 highly pathogenic avian influenza virus (HPAIVs) were isolated from three whooper swans (Cygnus cygnus) at Gangjin Bay in South Jeolla province, South Korea. Identification of HPAIVs in wild birds is significant as there is a potential risk of transmission of these viruses to poultry and humans. Phylogenetic analysis revealed that Gangjin H5N6 viruses classified into Asian H5 clade 2.3.4.4 lineage and were distinguishable from H5N8 and H5N1 HPAIVs previously isolated in Korea. With the exception of the polymerase acidic (PA) gene, the viruses were most closely related to A/duck/Guangdong/01.01SZSGXJK005-Y/2016 (H5N6) (98.90 ~ 99.74%). The PA genes of the two novel Gangjin H5N6 viruses were most closely related to AIV isolates previously characterized from Korea, A/hooded crane/Korea/1176/2016 (H1N1) (99.16%) and A/environment/Korea/W133/2006 (H7N7) (98.65%). The lack of more recent viruses to A/environment/Korea/W133/2006 (H7N7) indicates the need for analysis of recent wild bird AIVs isolated in Korea because they might provide further clues as to the origin of these novel reassortant H5N6 viruses. Although research on the origins and epidemiology of these infections is ongoing, the most likely route of infection for the whooper swans was through direct or indirect contact with reassortant viruses shed by migratory wild birds in Korea. As H5N6 HPAIVs can potentially be transmitted to poultry and humans, continuous monitoring of AIVs among wild birds will help to mitigate this risk.

  17. Faithfully quadratic rings

    CERN Document Server

    Dickmann, M

    2015-01-01

    In this monograph the authors extend the classical algebraic theory of quadratic forms over fields to diagonal quadratic forms with invertible entries over broad classes of commutative, unitary rings where -1 is not a sum of squares and 2 is invertible. They accomplish this by: (1) Extending the classical notion of matrix isometry of forms to a suitable notion of T-isometry, where T is a preorder of the given ring, A, or T = A^2. (2) Introducing in this context three axioms expressing simple properties of (value) representation of elements of the ring by quadratic forms, well-known to hold in

  18. BERKELEY: ALS ring

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1993-06-15

    Everybody at Lawrence Berkeley Laboratory's Center for Beam Physics is pleased with the rapid progress in commissioning LBL's Advanced Light Source (ALS) electron storage ring, the foundation for this third-generation synchrotron radiation facility. Designed for a maximum current of 400 mA, the ALS storage ring reached 407 mA just 24 days after storing the first beam on 16 March. ALS construction as a US Department of Energy (DOE) national user facility to provide high-brightness vacuum ultra-violet and soft x-ray radiation began in October 1987. One technical requirement marking project completion was to accumulate a 50-mA current in the storage ring. The ALS passed this milestone on 24 March, a week ahead of the official deadline. Once injected, the electron beam decays quasi-exponentially primarily because of interactions with residual gas molecules in the storage-ring vacuum chamber. Eventually, when the pressure in the vacuum chamber with beam decreases toward the expected operating level of 1 nano Torr, it will only be necessary to refill the storage ring at intervals of four to eight hours. At present the vacuum is improving rapidly as surfaces are irradiated (scrubbed) by the synchrotron radiation itself. At 100 mA, beam lifetime was about one hour (9 April)

  19. Compressible Vortex Ring

    Science.gov (United States)

    Elavarasan, Ramasamy; Arakeri, Jayawant; Krothapalli, Anjaneyulu

    1999-11-01

    The interaction of a high-speed vortex ring with a shock wave is one of the fundamental issues as it is a source of sound in supersonic jets. The complex flow field induced by the vortex alters the propagation of the shock wave greatly. In order to understand the process, a compressible vortex ring is studied in detail using Particle Image Velocimetry (PIV) and shadowgraphic techniques. The high-speed vortex ring is generated from a shock tube and the shock wave, which precedes the vortex, is reflected back by a plate and made to interact with the vortex. The shadowgraph images indicate that the reflected shock front is influenced by the non-uniform flow induced by the vortex and is decelerated while passing through the vortex. It appears that after the interaction the shock is "split" into two. The PIV measurements provided clear picture about the evolution of the vortex at different time interval. The centerline velocity traces show the maximum velocity to be around 350 m/s. The velocity field, unlike in incompressible rings, contains contributions from both the shock and the vortex ring. The velocity distribution across the vortex core, core diameter and circulation are also calculated from the PIV data.

  20. BERKELEY: ALS ring

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    Everybody at Lawrence Berkeley Laboratory's Center for Beam Physics is pleased with the rapid progress in commissioning LBL's Advanced Light Source (ALS) electron storage ring, the foundation for this third-generation synchrotron radiation facility. Designed for a maximum current of 400 mA, the ALS storage ring reached 407 mA just 24 days after storing the first beam on 16 March. ALS construction as a US Department of Energy (DOE) national user facility to provide high-brightness vacuum ultra-violet and soft x-ray radiation began in October 1987. One technical requirement marking project completion was to accumulate a 50-mA current in the storage ring. The ALS passed this milestone on 24 March, a week ahead of the official deadline. Once injected, the electron beam decays quasi-exponentially primarily because of interactions with residual gas molecules in the storage-ring vacuum chamber. Eventually, when the pressure in the vacuum chamber with beam decreases toward the expected operating level of 1 nano Torr, it will only be necessary to refill the storage ring at intervals of four to eight hours. At present the vacuum is improving rapidly as surfaces are irradiated (scrubbed) by the synchrotron radiation itself. At 100 mA, beam lifetime was about one hour (9 April)

  1. Accidental ingestion of BiTine ring and a note on inefficient ring separation forceps

    Directory of Open Access Journals (Sweden)

    Baghele ON

    2011-05-01

    Full Text Available Om Nemichand Baghele1, Mangala Om Baghele21Department of Periodontology, SMBT Dental College and Hospital, Sangamner, Ahmednagar, Maharashtra, India; 2Private General Dental Practice, Mumbai, IndiaBackground: Accidental ingestion of medium-to-large instruments is relatively uncommon during dental treatment but can be potentially dangerous. A case of BiTine ring ingestion is presented with a note on inefficient ring separation forceps.Case description: A 28-year-old male patient accidentally ingested the BiTine ring (2 cm diameter, 0.5 cm outward projections while it was being applied to a distoproximal cavity in tooth # 19. The ring placement forceps were excessively flexible; bending of the beaks towards the ring combined with a poor no-slippage mechanism led to sudden disengagement of the ring and accelerated movement towards the pharynx. We followed the patient with bulk forming agents and radiographs. Fortunately the ring passed out without any complications.Clinical implications: Checking equipment and methods is as important as taking precautions against any preventable medical emergency. It is the responsibility of the clinician to check, verify and then use any instrument/equipment.Keywords: foreign bodies/radiography, foreign bodies/complications, equipment failure, dental instrument, accidental ingestion

  2. On the Laurent polynomial rings

    International Nuclear Information System (INIS)

    Stefanescu, D.

    1985-02-01

    We describe some properties of the Laurent polynomial rings in a finite number of indeterminates over a commutative unitary ring. We study some subrings of the Laurent polynomial rings. We finally obtain two cancellation properties. (author)

  3. The Hi-Ring DCN Architecture

    DEFF Research Database (Denmark)

    Galili, Michael; Kamchevska, Valerija; Ding, Yunhong

    2016-01-01

    We will review recent work on the proposed hierarchical ring-based architecture (HiRing) proposed for data center networks. We will discuss the architecture and initial demonstrations of optical switching performance and time-domain synchronization......We will review recent work on the proposed hierarchical ring-based architecture (HiRing) proposed for data center networks. We will discuss the architecture and initial demonstrations of optical switching performance and time-domain synchronization...

  4. Natural radionuclides tracing in marine surface waters along the northern coast of Oman Sea by combining the radioactivity analysis, oceanic currents and the SWAN model results

    International Nuclear Information System (INIS)

    Zare, Mohammad Reza; Mostajaboddavati, Mojtaba; Kamali, Mahdi; Tari, Marziyeh; Mosayebi, Sanaz; Mortazavi, Mohammad Seddigh

    2015-01-01

    Highlights: • This study estimates radioactive pollution diffusion in coastline of the Oman Sea. • 36 high volume surface water samples were analyzed using a portable HPGe detector. • Oceanic currents in the northern coast of Oman Sea were investigated. • The spectral wave model SWAN was used for wave parameters simulation. • Currents and preferable wave directions were coupled with higher radioactivity. - Abstract: This study aims to establish a managed sampling plan for rapid estimate of natural radio-nuclides diffusion in the northern coast of the Oman Sea. First, the natural radioactivity analysis in 36 high volume surface water samples was carried out using a portable high-resolution gamma-ray spectrometry. Second, the oceanic currents in the northern coast were investigated. Then, the third generation spectral SWAN model was utilized to simulate wave parameters. Direction of natural radioactivity propagation was coupled with the preferable wave vectors and oceanic currents direction that face to any marine pollution, these last two factors will contribute to increase or decrease of pollution in each grid. The results were indicated that the natural radioactivity concentration between the grids 8600 and 8604 is gathered in the grid 8600 and between the grids 8605 and 8608 is propagated toward middle part of Oman Sea

  5. EBT ring physics

    International Nuclear Information System (INIS)

    Uckan, N.A.

    1980-04-01

    This workshop attempted to evaluate the status of the current experimental and theoretical understanding of hot electron ring properties. The dominant physical processes that influence ring formation, scaling, and their optimal behavior are also studied. Separate abstracts were prepared for each of the 27 included papers

  6. Ground Movement in SSRL Ring

    International Nuclear Information System (INIS)

    Sunikumar, Nikita

    2011-01-01

    Users of the Stanford Synchrotron Radiation Lightsource (SSRL) are being affected by diurnal motion of the synchrotron's storage ring, which undergoes structural changes due to outdoor temperature fluctuations. In order to minimize the effects of diurnal temperature fluctuations, especially on the vertical motion of the ring floor, scientists at SSRL tried three approaches: painting the storage ring white, covering the asphalt in the middle of the ring with highly reflective Mylar and installing Mylar on a portion of the ring roof and walls. Vertical motion in the storage ring is measured by a Hydrostatic Leveling System (HLS), which calculates the relative height of water in a pipe that extends around the ring. The 24-hr amplitude of the floor motion was determined using spectral analysis of HLS data, and the ratio of this amplitude before and after each experiment was used to quantitatively determine the efficacy of each approach. The results of this analysis showed that the Mylar did not have any significant effect on floor motion, although the whitewash project did yield a reduction in overall HLS variation of 15 percent. However, further analysis showed that the reduction can largely be attributed to a few local changes rather than an overall reduction in floor motion around the ring. Future work will consist of identifying and selectively insulating these local regions in order to find the driving force behind diurnal floor motion in the storage ring.

  7. Token ring technology report

    CERN Document Server

    2013-01-01

    Please note this is a Short Discount publication. This report provides an overview of the IBM Token-Ring technology and products built by IBM and compatible vendors. It consists of two sections: 1. A summary of the design trade-offs for the IBM Token-Ring. 2. A summary of the products of the major token-ring compatible vendors broken down by adapters and components, wiring systems, testing, and new chip technology.

  8. Prototype moving-ring reactor

    International Nuclear Information System (INIS)

    Smith, A.C. Jr.; Ashworth, C.P.; Abreu, K.E.

    1982-01-01

    We have completed a design of the Prototype Moving-Ring Reactor. The fusion fuel is confined in current-carrying rings of magnetically-field-reversed plasma (Compact Toroids). The plasma rings, formed by a coaxial plasma gun, undergo adiabatic magnetic compression to ignition temperature while they are being injected into the reactor's burner section. The cylindrical burner chamber is divided into three burn stations. Separator coils and a slight axial guide field gradient are used to shuttle the ignited toroids rapidly from one burn station to the next, pausing for 1/3 of the total burn time at each station. D-T- 3 He ice pellets refuel the rings at a rate which maintains constant radiated power

  9. Polycomb Group Proteins RING1A and RING1B Regulate the Vegetative Phase Transition in Arabidopsis

    Directory of Open Access Journals (Sweden)

    Jian Li

    2017-05-01

    Full Text Available Polycomb group (PcG protein-mediated gene silencing is a major regulatory mechanism in higher eukaryotes that affects gene expression at the transcriptional level. Here, we report that two conserved homologous PcG proteins, RING1A and RING1B (RING1A/B, are required for global H2A monoubiquitination (H2Aub in Arabidopsis. The mutation of RING1A/B increased the expression of members of the SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL gene family and caused an early vegetative phase transition. The early vegetative phase transition observed in ring1a ring1b double mutant plants was dependent on an SPL family gene, and the H2Aub status of the chromatin at SPL locus was dependent on RING1A/B. Moreover, mutation in RING1A/B affected the miRNA156a-mediated vegetative phase transition, and RING1A/B and the AGO7-miR390-TAS3 pathway were found to additively regulate this transition in Arabidopsis. Together, our results demonstrate that RING1A/B regulates the vegetative phase transition in Arabidopsis through the repression of SPL family genes.

  10. Researches on the Piston Ring

    Science.gov (United States)

    Ehihara, Keikiti

    1944-01-01

    In internal combustion engines, steam engines, air compressors, and so forth, the piston ring plays an important role. Especially, the recent development of Diesel engines which require a high compression pressure for their working, makes, nowadays, the packing action of the piston ring far more important than ever. Though a number of papers have been published in regard to researches on the problem of the piston ring, none has yet dealt with an exact measurement of pressure exerted on the cylinder wall at any given point of the ring. The only paper that can be traced on this subject so far is Mr. Nakagawa's report on the determination of the relative distribution of pressure on the cylinder wall, but the measuring method adopted therein appears to need further consideration. No exact idea has yet been obtained as to how the obturation of gas between the piston and cylinder, the frictional resistance of the piston, and the wear of the cylinder wall are affected by the intensity and the distribution of the radial pressure of the piston ring. Consequently, the author has endeavored, by employing an apparatus of his own invention, to get an exact determination of the pressure distribution of the piston ring. By means of a newly devised ring tester, to which piezoelectricity of quartz was applied, the distribution of the radial pressure of many sample rings on the market was accurately determined. Since many famous piston rings show very irregular pressure distribution, the author investigated and achieved a manufacturing process of the piston ring which will exert uniform pressure on the cylinder wall. Temperature effects on the configuration and on the mean spring power have also been studied. Further, the tests were performed to ascertain how the gas tightness of the piston ring may be affected by the number or spring power. The researches as to the frictional resistance between the piston ring and the cylinder wall were carried out, too. The procedure of study, and

  11. Generation of stable mixed-compact-toroid rings by inducing plasma currents in strong E rings

    International Nuclear Information System (INIS)

    Jayakumar, R.; Taggart, D.P.; Parker, M.R.; Fleischmann, H.H.

    1989-01-01

    In the RECE-Christa device, hybrid-type compact toroid rings are generated by inducing large toroidal plasma currents I rho in strong electron rings using a thin induction coil positioned along the ring axis. Starting from field-reversal values δ ο = 50 - 120 percent of the original pure fast-electron ring, the induced plasma current I rho raises δ to a maximum value of up to 240 percent with I rho contributing more than 50 percent of the total ring current. Quite interestingly, the generated hybrid compact toroid configurations appear gross-stable during the full I rho pulse length (half-amplitude width about 100 μs)

  12. Magnetization of two coupled rings

    International Nuclear Information System (INIS)

    Avishai, Y; Luck, J M

    2009-01-01

    We investigate the persistent currents and magnetization of a mesoscopic system consisting of two clean metallic rings sharing a single contact point in a magnetic field. Many novel features with respect to the single-ring geometry are underlined, including the explicit dependence of wavefunctions on the Aharonov-Bohm fluxes, the complex pattern of two-fold and three-fold degeneracies, the key role of length and flux commensurability, and in the case of commensurate ring lengths the occurrence of idle levels which do not carry any current. Spin-orbit interactions, induced by the electric fields of charged wires threading the rings, give rise to a peculiar version of the Aharonov-Casher effect where, unlike for a single ring, spin is not conserved. Remarkably enough, this can only be realized when the Aharonov-Bohm fluxes in both rings are neither integer nor half-integer multiples of the flux quantum

  13. Radioactive gold ring dermatitis

    International Nuclear Information System (INIS)

    Miller, R.A.; Aldrich, J.E.

    1990-01-01

    A superficial squamous cell carcinoma developed in a woman who wore a radioactive gold ring for more than 30 years. Only part of the ring was radioactive. Radiation dose measurements indicated that the dose to basal skin layer was 2.4 Gy (240 rad) per week. If it is assumed that the woman continually wore her wedding ring for 37 years since purchase, she would have received a maximum dose of approximately 4600 Gy

  14. Analytical model for double split ring resonators with arbitrary ring width

    DEFF Research Database (Denmark)

    Zhurbenko, Vitaliy; Jensen, Thomas; Krozer, Viktor

    2008-01-01

    For the first time, the analytical model for a double split ring resonator with unequal width rings is developed. The proposed models for the resonators with equal and unequal widths are based on an impedance matrix representation and provide the prediction of performance in a wide frequency range...

  15. A 13,500 Year Record of Holocene Climate, Fire and Vegetation from Swan Lake, Idaho, USA

    Science.gov (United States)

    Wahl, D.; Anderson, L.; Miller, D. M.; Rosario, J. J.; Starratt, S.; McGeehin, J. P.; Bright, J. E.

    2015-12-01

    Modern climate dynamics in the western US are largely determined by a combination of two factors: 1) the strength and position of midlatitude pressure systems, which, in turn, are responsible for the generation and trajectory of winter storms, and 2) the strength of the North America Monsoon (NAM) which brings summer precipitation northward in response to northern hemisphere warming. Paleoclimate records from the Great Basin of the western US suggest some coherence in the timing of major climatic shifts during the Holocene. However, knowledge of the timing and magnitude of these changes at local scales, which can help explain the relative contribution of midlatitude winter storms vs. NAM, is lacking in many places. Here we present new data that constrain the timing and magnitude of late glacial and Holocene climate variability in the northeastern Great Basin, provide insight into past spatial variability of precipitation patterns in the western US, and improve our understanding of regional scale influences on Great Basin climate. In 2011, a 7.65 m sediment core was raised from Swan Lake, a small wetland located in southeastern Idaho that was formed in the spillway channel created by the catastrophic flooding of Lake Bonneville ~18 ka BP. Pollen, charcoal, clumped isotope, diatom, ostracod, and sedimentological data are used to reconstruct vegetation, fire history, and lake level/groundwater flux over the last 13,500 years. Age control is provided by 19 AMS radiocarbon determinations, which are reported as thousands of calibrated years before present (ka BP). This effort builds on earlier work by Bright (1966) who reported on pollen, macrofossils, and sediment type from Swan Lake. Our data suggest cool and wet conditions prevailed until around 12.3 ka BP, after which a drying trend begins. The early Holocene was marked by a warmer, drier climate, which persisted until around 6.2 ka BP. Moister conditions after 6.2 ka BP likely resulted from a combination of enhanced

  16. Pure subrings of the rings

    International Nuclear Information System (INIS)

    Tsarev, Andrei V

    2009-01-01

    Pure subrings of finite rank in the Z-adic completion of the ring of integers and in its homomorphic images are considered. Certain properties of these rings are studied (existence of an identity element, decomposability into a direct sum of essentially indecomposable ideals, condition for embeddability into a csp-ring, etc.). Additive groups of these rings and conditions under which these rings are subrings of algebraic number fields are described. Bibliography: 12 titles.

  17. Ring accelerators

    International Nuclear Information System (INIS)

    Gisler, G.; Faehl, R.

    1983-01-01

    We present two-dimensional simulations in (r-z) and r-theta) cylinderical geometries of imploding-liner-driven accelerators of rings of charged particles. We address issues of azimuthal and longitudinal stability of the rings. We discuss self-trapping designs in which beam injection and extraction is aided by means of external cusp fields. Our simulations are done with the 2-1/2-D particle-in-cell plasma simulation code CLINER, which combines collisionless, electromagnetic PIC capabilities with a quasi-MHD finite element package

  18. Compound Extremes and Bunched Black (or Grouped Grey) Swans

    Science.gov (United States)

    Watkins, N. W.

    2014-12-01

    Observed "wild" natural fluctuations may differ substantially in their character. Some events may be genuinelyunforeseen (and unforeseeable), as with Taleb's "black swans". These may occur singly, or may have their impactfurther magnified by being "bunched" in time. Some of the others may, however, be the rare extreme events from alight-tailed underlying distribution. Studying their occurrence may then be tractable with the methods of extremevalue theory [e.g. Coles, 2001], suitably adapted to allow correlation if that is observed to be present. Yet others may belong to a third broad class, described in today's presentation [ reviewed in Watkins, GRLFrontiers, 2013, doi: 10.1002/grl.50103]. Such "bursty" time series may show comparatively frequent highamplitude events, and/or long range correlations between successive values. The frequent large values due to thefirst of these effects, modelled in economics by Mandelbrot in 1963 using heavy- tailed probability distributions,can give rise to an "IPCC type I" burst composed of successive wild events. Conversely, long range dependence,even in a light-tailed Gaussian model like Mandelbrot and van Ness' fractional Brownian motion, can integrate"mild" events into an extreme "IPCC type III" burst. I will show how a standard statistical time series model, linear fractional stable motion (LFSM), which de-scends from the two special cases advocated by Mandelbrot, allows these two effects to be varied independently,and will present results from a preliminary study of such bursts in LFSM. The consequences for burst scaling whenlow frequency effects due to dissipation (FARIMA models), and multiplicative cascades (such as multifractals)are included will also be discussed, and the physical assumptions and constraints associated with making a givenchoice of model.

  19. Manipulation of vortex rings for flow control

    International Nuclear Information System (INIS)

    Toyoda, Kuniaki; Hiramoto, Riho

    2009-01-01

    This paper reviews the dynamics of vortex rings and the control of flow by the manipulation of vortex rings. Vortex rings play key roles in many flows; hence, the understanding of the dynamics of vortex rings is crucial for scientists and engineers dealing with flow phenomena. We describe the structures and motions of vortex rings in circular and noncircular jets, which are typical examples of flows evolving into vortex rings. For circular jets the mechanism of evolving, merging and breakdown of vortex rings is described, and for noncircular jets the dynamics of three-dimensional deformation and interaction of noncircular vortex rings under the effect of self- and mutual induction is discussed. The application of vortex-ring manipulation to the control of various flows is reviewed with successful examples, based on the relationship between the vortex ring dynamics and the flow properties. (invited paper)

  20. The Rings of Saturn

    Science.gov (United States)

    Cuzzi, J. N.; Filacchione, G.; Marouf, E. A.

    2018-03-01

    One could become an expert on Saturn's iconic rings pretty easily in the early 1970s, as very little was known about them beyond the distinction between the A, B, and C rings, and the Cassini Division or "gap" between rings A and B (Alexander, 1962; Bobrov, 1970). Water ice was discovered spectroscopically on the ring particle surfaces, and radar and microwave emission observations proved that the particles must be centimeters to meters in size, consisting primarily, not just superficially, of water ice (Pollack, 1975). While a 2:1 orbital resonance with Mimas had long been suspected of having something to do with the Cassini Division, computers of the time were unable to model the subtle dynamical effects that we now know to dominate ring structure. This innocent state of affairs was exploded by the Voyager 1 and 2 encounters in 1980 and 1981. Spectacular images revealed filigree structure and odd regional color variations, and exquisitely detailed radial profiles of fluctuating particle abundance were obtained from the first stellar and radio occultations, having resolution almost at the scale of single particles. Voyager-era understanding was reviewed by Cuzzi et al. (1984) and Esposito et al. (1984). While the Voyager data kept ring scientists busy for decades, planning which led to the monumentally successful NASA-ESA-ASI Cassini mission, which arrived in 2004, had been under way even before Voyager got to Saturn. A review of pre-Cassini knowledge of Saturn's Rings can be found in Orton et al. (2009). This chapter will build on recent topical and process-specific reviews that treat the gamut of ring phenomena and its underlying physics in considerable detail (Colwell et al., 2009; Cuzzi et al., 2009; Horányi et al., 2009; Schmidt et al., 2009; Esposito, 2010; Tiscareno, 2013b; Esposito, 2014). We will follow and extend the general organization of Cuzzi et al. (2010), the most recent general discussion of Saturn's rings. For brevity and the benefit of the

  1. Examination techniques for non-magnetic rings

    International Nuclear Information System (INIS)

    Metala, M.J.; Kilpatrick, N.L.; Frank, W.W.

    1990-01-01

    Until the introduction of 18Mn18Cr rings a few years ago, most non-magnetic steel rings for generator rotors were made from 18Mn5Cr alloy steel, which is highly susceptible to stress corrosion cracking in the presence of water. This, the latest in a series of papers on the subject of non-magnetic rings by the authors' company, provides a discussion of nondestructive examination of 18Mn5Cr rings for stress corrosion distress. With rings on the rotor, fluorescent penetrant, ultrasonic and special visual techniques are applied. With rings off the rotor, the fluorescent penetrant technique is used, with and without stress enhancement

  2. Ionization cooling ring for muons

    Directory of Open Access Journals (Sweden)

    R. Palmer

    2005-06-01

    Full Text Available Practical ionization cooling rings could lead to lower cost or improved performance in neutrino factory or muon collider designs. The ring modeled here uses realistic three-dimensional fields. The performance of the ring compares favorably with the linear cooling channel used in the second U.S. Neutrino Factory Study. The normalized 6D emittance of an ideal ring is decreased by a factor of approximately 240, compared with a factor of only 15 for the linear channel. We also examine such real-world effects as windows on the absorbers and rf cavities and leaving empty lattice cells for injection and extraction. For realistic conditions the ring decreases the normalized 6D emittance by a factor of 49.

  3. Self-gravitation in Saturn's rings

    International Nuclear Information System (INIS)

    Salo, H.; Lukkari, J.

    1982-01-01

    In a ring-shaped collisional system self-gravitation reduces the equilibrium values of the geometric and optical thickness. In Saturn's rings both effects are appreciable. The previously found discrepancy between the calculated profile and the observed profile of the rings is chiefly caused by the omission of self-gravitation. (Auth.)

  4. Saturn’s ring temperatures at equinox

    Science.gov (United States)

    Spilker, Linda J.; Ferrari, C.; Morishima, R.

    2013-10-01

    Modeling the thermal emission of Saturn's rings is challenging due to the numerous heating sources as well as the structural properties of the disk and of the particles that are closely related. At equinox, however, the main rings are externally heated by Saturn alone and the problem is somewhat simplified. We test the abilities of our current models to reproduce the temperatures observed with the Cassini CIRS instrument around equinox in August 2009. A simple semi-analytic model which includes mutual shadowing effects can mostly explain the radial profile of the equinox ring temperatures, except the model predicts lower temperatures than those observed for the A ring. The temperature variation at a given saturnocentric radius is primarily caused by observational geometry variations relative to Saturn. The observed temperature increases with decreasing Saturn-ring-observer angle. In addition, we found evidence that the leading hemispheres of particles are warmer than the trailing hemispheres at least for the C ring and probably for the A and B rings as well. This is explained if some fraction of particles has spin rates lower than the synchronous rotation rate as predicted by N-body simulations. The spin model for a monolayer ring (Ferrari, C., Leyrat, C., 2006, Astron. Astrophys. 447, 745-760) can fit the temperature variations with spacecraft longitude observed in the C ring with currently known thermal properties and a mixing of slow and fast rotators. The multilayer model (Morishima, R., Salo, H., Ohtsuki, K., 2009, Icarus 201, 634-654) can reproduce the temperatures of the B and C rings but gives A ring temperatures that are significantly lower than those observed as does the simple semi-analytic model. More advanced models which take into account self-gravity wakes may explain the A ring temperature behavior.

  5. Split ring containment attachment device

    International Nuclear Information System (INIS)

    Sammel, A.G.

    1996-01-01

    A containment attachment device is described for operatively connecting a glovebag to plastic sheeting covering hazardous material. The device includes an inner split ring member connected on one end to a middle ring member wherein the free end of the split ring member is inserted through a slit in the plastic sheeting to captively engage a generally circular portion of the plastic sheeting. A collar potion having an outer ring portion is provided with fastening means for securing the device together wherein the glovebag is operatively connected to the collar portion. 5 figs

  6. Von Krahli Teatri „Luikede järv“ kui mälumasin: esteetiline absoluut ja sotsiaalne kontekst / Von Krahl Theatre’s “Swan Lake” as a Memory Machine: Aesthetic Absolute and Social Context

    Directory of Open Access Journals (Sweden)

    Riina Oruaas

    2014-12-01

    Full Text Available This paper analyses the interrelation between video projections and stage action and the meanings created via these relations in Von Krahl Theatre’s production of „Swan Lake“ (2003, directors Peeter Jalakas and Alexander Pepelyayev. „Swan Lake“ at Von Krahl Theatre was a post-modern interpretation of Tchaikovsky’s ballet that deconstructed myths of Soviet society. In the conceptual introduction to the performance, the directors dedicated the production to the theme of absolute beauty and aesthetic ideal, and claimed the synthesis of aesthetic and social contexts to be of utmost importance. The performance analysis in this article reveals the ambivalence of the aesthetic absolute and position of the ballet „Swan Lake“ as an icon. The context of this production was layered through the social and political, as well as artistic processes that influenced the reception of the performance. The social and aesthetic context is analysed based on Mieke Bal’s concept of framing, which is more dynamic and open than understanding context as something fixed. The analysis of screens and the stage action is based on the theoretical models of intermediality in performing arts.  The central section of this paper is focused on analysing the stage action and the relationship between the stage action and video projections as techniques of dissonance. This work by Jalakas and Pepelyaev was a multimedia dance performance where video clips of the ballets „Swan Lake“ and „The Dying Swan“ alternated with footages of Soviet heavy industry, war apparatus, athletes, etc. The various oppositions and parallels between the stage action and screen footage made the political meaning of the performance visible. The paper also analyses the narrative structure, the cast of characters and scenography. There was a certain hierarchy in the cast (actors versus dancers and character structure (politicians, Black and White Swan, and the corps de ballet which was

  7. An N-body Integrator for Planetary Rings

    Science.gov (United States)

    Hahn, Joseph M.

    2011-04-01

    A planetary ring that is disturbed by a satellite's resonant perturbation can respond in an organized way. When the resonance lies in the ring's interior, the ring responds via an m-armed spiral wave, while a ring whose edge is confined by the resonance exhibits an m-lobed scalloping along the ring-edge. The amplitude of these disturbances are sensitive to ring surface density and viscosity, so modelling these phenomena can provide estimates of the ring's properties. However a brute force attempt to simulate a ring's full azimuthal extent with an N-body code will likely fail because of the large number of particles needed to resolve the ring's behavior. Another impediment is the gravitational stirring that occurs among the simulated particles, which can wash out the ring's organized response. However it is possible to adapt an N-body integrator so that it can simulate a ring's collective response to resonant perturbations. The code developed here uses a few thousand massless particles to trace streamlines within the ring. Particles are close in a radial sense to these streamlines, which allows streamlines to be treated as straight wires of constant linear density. Consequently, gravity due to these streamline is a simple function of the particle's radial distance to all streamlines. And because particles are responding to smooth gravitating streamlines, rather than discrete particles, this method eliminates the stirring that ordinarily occurs in brute force N-body calculations. Note also that ring surface density is now a simple function of streamline separations, so effects due to ring pressure and viscosity are easily accounted for, too. A poster will describe this N-body method in greater detail. Simulations of spiral density waves and scalloped ring-edges are executed in typically ten minutes on a desktop PC, and results for Saturn's A and B rings will be presented at conference time.

  8. Minimal Gromov-Witten rings

    International Nuclear Information System (INIS)

    Przyjalkowski, V V

    2008-01-01

    We construct an abstract theory of Gromov-Witten invariants of genus 0 for quantum minimal Fano varieties (a minimal class of varieties which is natural from the quantum cohomological viewpoint). Namely, we consider the minimal Gromov-Witten ring: a commutative algebra whose generators and relations are of the form used in the Gromov-Witten theory of Fano varieties (of unspecified dimension). The Gromov-Witten theory of any quantum minimal variety is a homomorphism from this ring to C. We prove an abstract reconstruction theorem which says that this ring is isomorphic to the free commutative ring generated by 'prime two-pointed invariants'. We also find solutions of the differential equation of type DN for a Fano variety of dimension N in terms of the generating series of one-pointed Gromov-Witten invariants

  9. Electro-optical hybrid slip ring

    Science.gov (United States)

    Hong, En

    2005-11-01

    The slip ring is a rotary electrical interface, collector, swivel or rotary joint. It is a physical system that can perform continuous data transfer and data exchange between a stationary and a rotating structure. A slip ring is generally used to transfer data or power from an unrestrained, continuously rotating electro-mechanical system in real-time, thereby simplifying operations and eliminating damage-prone wires dangling from moving joints. Slip rings are widely used for testing, evaluating, developing and improving various technical equipment and facilities with rotating parts. They are widely used in industry, especially in manufacturing industries employing turbo machinery, as in aviation, shipbuilding, aerospace, defense, and in precise facilities having rotating parts such as medical Computerized Tomography (CT) and MRI scanners and so forth. Therefore, any improvement in slip ring technology can impact large markets. Research and development in this field will have broad prospects long into the future. The goal in developing the current slip ring technology is to improve and increase the reliability, stability, anti-interference, and high data fidelity between rotating and stationary structures. Up to now, there have been numerous approaches used for signal and data transfer utilizing a slip ring such as metal contacts, wires, radio transmission, and even liquid media. However, all suffer from drawbacks such as data transfer speed limitations, reliability, stability, electro-magnetic interference and durability. The purpose of the current research is to break through these basic limitations using an optical solution, thereby improving performance in current slip ring applications. This dissertation introduces a novel Electro-Optical Hybrid Slip Ring technology, which makes "through the air" digital-optical communication between stationary and rotating systems a reality with high data transfer speed, better reliability and low interference susceptibility

  10. Double acting stirling engine piston ring

    Science.gov (United States)

    Howarth, Roy B.

    1986-01-01

    A piston ring design for a Stirling engine wherein the contact pressure between the piston and the cylinder is maintained at a uniform level, independent of engine conditions through a balancing of the pressure exerted upon the ring's surface and thereby allowing the contact pressure on the ring to be predetermined through the use of a preloaded expander ring.

  11. Fourier spectroscopy of the 12C2, 13C2, and 12C13C (0-0) swan bands

    International Nuclear Information System (INIS)

    Amiot, C.

    1983-01-01

    The (0-0) band of the C 2 Swan electronic system d 3 Pi/sub g/→a 3 Pi/sub u/ has been recorded by Fourier spectroscopy. The three isotopes species 12 C 2 , 13 C 2 , and 12 C 13 C were investigated. The observed wavenumbers were reduced to molecular parameters using a nonlinear least-square fitting procedure. Well-known perturbations at N' = 47 and N' = 51 again observed in the e 12 C 2 d 3 Pi/sub g/ (v = 0) level. Perturbations of the same kind are present in the 13 C 2 spectrum at N' = 34 and N' = 44,48,52. The 12 C 13 C spectrum exhibits in the observed spectral range a unique perturbation for N' = 41

  12. Fusion Rings for Quantum Groups

    DEFF Research Database (Denmark)

    Andersen, Henning Haahr; Stroppel, Catharina

    2012-01-01

    We study the fusion rings of tilting modules for a quantum group at a root of unity modulo the tensor ideal of negligible tilting modules. We identify them in type A with the combinatorial rings from [12] and give a similar description of the sp2n-fusion ring in terms of noncommutative symmetric...

  13. Topological rings

    CERN Document Server

    Warner, S

    1993-01-01

    This text brings the reader to the frontiers of current research in topological rings. The exercises illustrate many results and theorems while a comprehensive bibliography is also included. The book is aimed at those readers acquainted with some very basic point-set topology and algebra, as normally presented in semester courses at the beginning graduate level or even at the advanced undergraduate level. Familiarity with Hausdorff, metric, compact and locally compact spaces and basic properties of continuous functions, also with groups, rings, fields, vector spaces and modules, and with Zorn''s Lemma, is also expected.

  14. Energy spectra of quantum rings.

    Science.gov (United States)

    Fuhrer, A; Lüscher, S; Ihn, T; Heinzel, T; Ensslin, K; Wegscheider, W; Bichler, M

    2001-10-25

    Quantum mechanical experiments in ring geometries have long fascinated physicists. Open rings connected to leads, for example, allow the observation of the Aharonov-Bohm effect, one of the best examples of quantum mechanical phase coherence. The phase coherence of electrons travelling through a quantum dot embedded in one arm of an open ring has also been demonstrated. The energy spectra of closed rings have only recently been studied by optical spectroscopy. The prediction that they allow persistent current has been explored in various experiments. Here we report magnetotransport experiments on closed rings in the Coulomb blockade regime. Our experiments show that a microscopic understanding of energy levels, so far limited to few-electron quantum dots, can be extended to a many-electron system. A semiclassical interpretation of our results indicates that electron motion in the rings is governed by regular rather than chaotic motion, an unexplored regime in many-electron quantum dots. This opens a way to experiments where even more complex structures can be investigated at a quantum mechanical level.

  15. Forandringslæring med autismediagnoser?

    DEFF Research Database (Denmark)

    Gustafson, Kari Ingrid; Mørck, Line Lerche

    2013-01-01

    Artiklen drøfter en række aktuelle spørgsmål omkring læring hos børn og unge med autisme-spektrum-forstyrrelses diagnoser. Der introduceres til en social praksisteoretisk forståelse af forandringslæring, der diskuterer forandring ikke kun i relation til en persons identitet, men også aktuelle og...... potentielle forandringer, når det gælder overskridelse af binær logik i autisme versus normalitet, samt i relation til at overskride individualiserede og dualistiske problem-forståelser af fejl og mangler ved det autistiske barn. Det illustreres, hvordan disse former for dualistisk tænkning er forankret i et...... Rasmus’ ændringer i læring, selvforståelse og tilhørsforhold perspektiveres med andre ASF-diagnostiseredes læring udforsket bl.a. gennem gruppeinterviews i regi af Asperger-foreningen. Artiklen byder således på et alternativ i form af at forstå forandringslæring som overskridende læring, med langt større...

  16. The Lord of Rings - the mysterious case of the stolen rings: a critical analysis

    Science.gov (United States)

    Sandrelli, S.

    The Lord of Rings - the mysterious case of the stolen rings: a critical analysis S. Sandrelli INAF - Osservatorio Astronomico di Brera, Milano, Italy (stefano.sandrelli@brera.inaf.it / Fax: 02 72001600 / Phone: +39 02 72320337) "The Lord of Rings - the mysterious case of the stolen rings" is a live astronomical role-playing game for kids aged 10 -13. Its goal is to introduce them to some of the main topics of the Solar System: a) the role of gravity; b) the distribution of mass & light; c) the effects of rotation; d) the distribution of water. The game was held both at the Perugia (2004) and the Genova Science Festival (2005), obtaining great success. Teams of about 6-8 members are introduced to Mr Schioppanelli, the astro-detective of the town (the name is a pun: it reminds Schiaparelli, the famous italian astronomer, and it is a slang expression meaning "ring-breaker"). Mr Schioppanelli has his office in an "gastronomical astronomical observatory", known as The Red Giant Pizzeria. Schioppanelli informs the kids that a mysterious Centaur succeded in stealing the rings of Saturn. The partecipants are appointed astro-detectives in-charge and asked to find the rings by browsing around the Solar System, which is scaled so as to fit the town historical centre or a pedestrian area, going from the Sun to Saturn or beyond, depending on the actual area at disposal. Great care must be taken allowing children playing only in a car-free area of the town. At the right scaled distances, the partecipants meet characters playing as the various planets. The kids can talk to them after solving a riddle, obtaining useful informations. A special characters play as a comet, timely going in and out of the inner solar system. The teams can also talk to some shepherd-moons of the rings. They easily discover that the rings were totally destroyed by the Centaur: a real disaster! They are also suggested to gather the necessary ingredients (gravity, light, rotation, inclination, dust and

  17. Vortex rings in classical and quantum systems

    International Nuclear Information System (INIS)

    Barenghi, C F; Donnelly, R J

    2009-01-01

    The study of vortex rings has been pursued for decades and is a particularly difficult subject. However, the discovery of quantized vortex rings in superfluid helium has greatly increased interest in vortex rings with very thin cores. While rapid progress has been made in the simulation of quantized vortex rings, there has not been comparable progress in laboratory studies of vortex rings in a viscous fluid such as water. This article overviews the history and current frontiers of classical and quantum vortex rings. After introducing the classical results, this review discusses thin-cored vortex rings in superfluid helium in section 2, and recent progress in understanding vortex rings of very thin cores propagating in water in section 3. (invited paper)

  18. Laparoscopic appendicectomy using endo-ring applicator and fallope rings

    International Nuclear Information System (INIS)

    Ali, Iyoob V; Maliekkal, Joji I

    2009-01-01

    Wider adoption of laparoscopic appendicectomy (LA) is limited by problems in securing the appendiceal base as well as the cost and the duration compared with the open procedure. The objective of this study was to assess the feasibility and efficacy of a new method for securing the appendiceal base in LA, so as to make the entire procedure simpler and cheaper, and hence, more popular. Twenty-five patients who were candidates for appendicectomy (emergency as well as elective) and willing for the laparoscopic procedure were selected for this study. Ports used were 10 mm at the umbilicus, 5 mm at the lower right iliac fossa, and 10 mm at the left iliac fossa. Extremely friable, ruptured, or turgid organs of diameters larger than 8 mm were excluded from the study. The mesoappendix was divided close to the appendix by diathermy. Fallope rings were applied to the appendiceal base using a special ring applicator, and the appendix was divided and extracted through the lumen of the applicator. The procedure was successful in 23 (92%) cases, and the mean duration of the procedure was 20 minutes (15-32 minutes). There were no procedural complications seen during a median follow-up of two weeks. The equipment and rings were cheaper when compared with that of the standard methods of securing the base of the appendix. LA using fallope rings is a safe, simple, easy-to-learn, and economically viable method. (author)

  19. SMARANDACHE NON-ASSOCIATIVE RINGS

    OpenAIRE

    Vasantha, Kandasamy

    2002-01-01

    An associative ring is just realized or built using reals or complex; finite or infinite by defining two binary operations on it. But on the contrary when we want to define or study or even introduce a non-associative ring we need two separate algebraic structures say a commutative ring with 1 (or a field) together with a loop or a groupoid or a vector space or a linear algebra. The two non-associative well-known algebras viz. Lie algebras and Jordan algebras are mainly built using a vecto...

  20. Heavy ion storage rings

    International Nuclear Information System (INIS)

    Schuch, R.

    1987-01-01

    A brief overview of synchrotron storage rings for heavy ions, which are presently under construction in different accelerator laboratories is given. Ions ranging from protons up to uranium ions at MeV/nucleon energies will be injected into these rings using multiturn injection from the accelerators available or being built in these laboratories. After injection, it is planned to cool the phase space distribution of the ions by merging them with cold electron beams or laser beams, or by using stochastic cooling. Some atomic physics experiments planned for these rings are presented. 35 refs

  1. Moving ring reactor 'Karin-1'

    International Nuclear Information System (INIS)

    1983-12-01

    The conceptual design of a moving ring reactor ''Karin-1'' has been carried out to advance fusion system design, to clarify the research and development problems, and to decide their priority. In order to attain these objectives, a D-T reactor with tritium breeding blanket is designed, a commercial reactor with net power output of 500 MWe is designed, the compatibility of plasma physics with fusion engineering is demonstrated, and some other guideline is indicated. A moving ring reactor is composed mainly of three parts. In the first formation section, a plasma ring is formed and heated up to ignition temperature. The plasma ring of compact torus is transported from the formation section through the next burning section to generate fusion power. Then the plasma ring moves into the last recovery section, and the energy and particles of the plasma ring are recovered. The outline of a moving ring reactor ''Karin-1'' is described. As a candidate material for the first wall, SiC was adopted to reduce the MHD effect and to minimize the interaction with neutrons and charged particles. The thin metal lining was applied to the SiC surface to solve the problem of the compatibility with lithium blanket. Plasma physics, the engineering aspect and the items of research and development are described. (Kako, I.)

  2. Tinkering at the main-ring lattice

    Energy Technology Data Exchange (ETDEWEB)

    Ohnuma, S.

    1982-08-23

    To improve production of usable antiprotons using the proton beam from the main ring and the lossless injection of cooled antiprotons into the main ring, modifications of the main ring lattice are recommended.

  3. The ring plus project: safety and acceptability of vaginal rings that protect women from unintended pregnancy

    OpenAIRE

    Schurmans, C?line; De Baetselier, Irith; Kestelyn, Evelyne; Jespers, Vicky; Delvaux, Th?r?se; Agaba, Stephen K; van Loen, Harry; Menten, Joris; van de Wijgert, Janneke; Crucitti, Tania

    2015-01-01

    Background Research is ongoing to develop multipurpose vaginal rings to be used continuously for contraception and to prevent Human Immunodeficiency Virus (HIV) infection. Contraceptive vaginal rings (CVRs) are available in a number of countries and are most of the time used intermittently i.e. three weeks out of a 4-week cycle. Efficacy trials with a dapivirine-containing vaginal ring for HIV prevention are ongoing and plans to develop multi-purpose vaginal rings for prevention of both HIV a...

  4. Pyrimidine-pyridine ring interconversion

    NARCIS (Netherlands)

    Plas, van der H.C.

    2003-01-01

    This chapter discusses the pyrimidine-to-pyridine ring transformation and pyridine-to-pyrimidine ring transformation. In nucleophile-induced pyrimidine-to-pyridine rearrangements, two types of reactions can be distinguished depending on the structure of the nucleophile: (1) reactions in which the

  5. Electron beam cooling at a magnetic storage ring, TARN II, and an electrostatic storage ring

    International Nuclear Information System (INIS)

    Tanabe, Tetsumi

    2006-01-01

    At the High Energy Accelerator Research Organization (KEK), a magnetic storage ring, TARN II, with an electron cooler was operated from 1989 to 1999, while an electrostatic storage ring with a small electron cooler has been operational since 2000. In this paper, the electron cooling at TARN II and the electrostatic storage ring is described. (author)

  6. Leapfrogging of multiple coaxial viscous vortex rings

    International Nuclear Information System (INIS)

    Cheng, M.; Lou, J.; Lim, T. T.

    2015-01-01

    A recent theoretical study [Borisov, Kilin, and Mamaev, “The dynamics of vortex rings: Leapfrogging, choreographies and the stability problem,” Regular Chaotic Dyn. 18, 33 (2013); Borisov et al., “The dynamics of vortex rings: Leapfrogging in an ideal and viscous fluid,” Fluid Dyn. Res. 46, 031415 (2014)] shows that when three coaxial vortex rings travel in the same direction in an incompressible ideal fluid, each of the vortex rings alternately slips through (or leapfrogs) the other two ahead. Here, we use a lattice Boltzmann method to simulate viscous vortex rings with an identical initial circulation, radius, and separation distance with the aim of studying how viscous effect influences the outcomes of the leapfrogging process. For the case of two identical vortex rings, our computation shows that leapfrogging can be achieved only under certain favorable conditions, which depend on Reynolds number, vortex core size, and initial separation distance between the two rings. For the case of three coaxial vortex rings, the result differs from the inviscid model and shows that the second vortex ring always slips through the leading ring first, followed by the third ring slipping through the other two ahead. A simple physical model is proposed to explain the observed behavior

  7. Redox shuttles having an aromatic ring fused to a 1,1,4,4-tetrasubstituted cyclohexane ring

    Science.gov (United States)

    Weng, Wei; Zhang, Zhengcheng; Amine, Khalil

    2015-12-01

    An electrolyte includes an alkali metal salt; an aprotic solvent; and a redox shuttle additive including an aromatic compound having at least one aromatic ring fused with at least one non-aromatic ring, the aromatic ring having two or more oxygen or phosphorus-containing substituents.

  8. Interaction of Vortex Ring with Cutting Plate

    Science.gov (United States)

    Musta, Mustafa

    2015-11-01

    The interaction of a vortex ring impinging on a thin cutting plate was made experimentally using Volumetric 3-component Velocitmetry (v3v) technique. The vortex rings were generated with piston-cylinder vortex ring generator using piston stroke-to-diameter ratios and Re at 2-3 and 1500 - 3000, respectively. The cutting of vortex rings below center line leads to the formation of secondary vortices on each side of the plate which is look like two vortex rings, and a third vortex ring propagates further downstream in the direction of the initial vortex ring, which is previously showed by flow visualization study of Weigand (1993) and called ``trifurcation''. Trifurcation is very sensitive to the initial Reynolds number and the position of the plate with respect to the vortex ring generator pipe. The present work seeks more detailed investigation on the trifurcation using V3V technique. Conditions for the formation of trifurcation is analyzed and compared with Weigand (1993). The formed secondary vortex rings and the propagation of initial vortex ring in the downstream of the plate are analyzed by calculating their circulation, energy and trajectories.

  9. Magnetic ring for stripping enhancement

    International Nuclear Information System (INIS)

    Selph, F.

    1992-10-01

    A ring designed to recycle ions through a stripping medium offers the possibility for increasing output of the desired charge state by up to 4x. This could be a very important component of a Radioactive Nuclear Beam Facility. In order for such a ring to work effectively it must satisfy certain design conditions. These include achromaticity at the stripper, a dispersed region for an extraction magnet, and a number of first and higher order optics constraints which are necessary to insure that the beam emittance is not degraded unduly by the ring. An example is given of a candidate design of a stripping ring

  10. Acceleration of magnetized plasma rings

    International Nuclear Information System (INIS)

    Hartman, D.; Eddleman, J.; Hammer, J.H.

    1982-01-01

    One scheme is considered, acceleration of a ring between coaxial electrodes by a B/sub theta/ field as in a coaxial rail-gun. If the electrodes are conical, a ring accelerated towards the apex of the cone undergoes self-similar compression (focussing) during acceleration. Because the allowable acceleration force F/sub a/ = kappa U/sub m//R (kappa - 2 , the accelerating distance for conical electrodes is considerably shortened over that required for coaxial electrodes. In either case however, since the accelerating flux can expand as the ring moves, most of the accelerating field energy can be converted into kinetic energy of the ring leading to high efficiency

  11. A first course in noncommutative rings

    CERN Document Server

    Lam, T Y

    2001-01-01

    A First Course in Noncommutative Rings, an outgrowth of the author's lectures at the University of California at Berkeley, is intended as a textbook for a one-semester course in basic ring theory. The material covered includes the Wedderburn-Artin theory of semisimple rings, Jacobson's theory of the radical, representation theory of groups and algebras, prime and semiprime rings, local and semilocal rings, perfect and semiperfect rings, etc. By aiming the level of writing at the novice rather than the connoisseur and by stressing th the role of examples and motivation, the author has produced a text that is suitable not only for use in a graduate course, but also for self- study in the subject by interested graduate students. More than 400 exercises testing the understanding of the general theory in the text are included in this new edition.

  12. Design of Piston Ring Friction Tester Apparatus

    DEFF Research Database (Denmark)

    Klit, Peder

    2006-01-01

    One of the major prerequisites for calculating piston ring friction is a good description of the tribological situation. Piston rings operate in three different lubrication regimes and the theoretical models should be capable to describe this. A very important condition for describing the frictio......One of the major prerequisites for calculating piston ring friction is a good description of the tribological situation. Piston rings operate in three different lubrication regimes and the theoretical models should be capable to describe this. A very important condition for describing...... the frictional behavior of a piston ring correctly is knowledge about the amount of lubricant present. For piston rings the external load may be established by measuring the pressure distribution, i.e. the pressure drop in the piston ring package. Speed and temperature may also be established. The amount...... available is reflected in the friction absorbed in the bearing. The following properties will be measured: Oil fillm thickness - along liner (axial variation), oil film thickness - along piston ring (circumferential variation), piston tilt, temperature of piston rings and liner, pressure at piston lands...

  13. Study for ILC Damping Ring at KEKB

    Energy Technology Data Exchange (ETDEWEB)

    Flanagan, J.W.; Fukuma, H.; Kanazawa, K.I.; Koiso, H.; Masuzawa, M.; Ohmi, Kazuhito; Ohnishi, Y.; Oide, Katsunobu; Suetsugu, Y.; Tobiyama, M.; /KEK, Tsukuba; Pivi, M.; /SLAC

    2011-11-04

    ILC damping ring consists of very low emittance electron and positron storage rings. It is necessary for ILC damping ring to study electron cloud effects in such low emittance positron ring. We propose a low emittance operation of KEKB to study the effects.

  14. Planetary ring systems properties, structures, and evolution

    CERN Document Server

    Murray, Carl D

    2018-01-01

    Planetary rings are among the most intriguing structures of our solar system and have fascinated generations of astronomers. Collating emerging knowledge in the field, this volume reviews our current understanding of ring systems with reference to the rings of Saturn, Uranus, Neptune, and more. Written by leading experts, the history of ring research and the basics of ring–particle orbits is followed by a review of the known planetary ring systems. All aspects of ring system science are described in detail, including specific dynamical processes, types of structures, thermal properties and their origins, and investigations using computer simulations and laboratory experiments. The concluding chapters discuss the prospects of future missions to planetary rings, the ways in which ring science informs and is informed by the study of other astrophysical disks, and a perspective on the field's future. Researchers of all levels will benefit from this thorough and engaging presentation.

  15. Longitudinal beam instability due to the ring impedance at KEK's accelerator test facility damping ring

    International Nuclear Information System (INIS)

    Kim, Eun-San

    2003-01-01

    This paper shows the results of a numerical study of the impedance in the Accelerator Test Facility damping ring. The longitudinal impedance in the damping ring is shown to be inductive. It is shown that the total impedance |Z || /n| is 0.23 Ω and the inductance is L = 14 nH. In the extremely low emittance beam of the damping ring, bunch lengthening is caused by both the effects of potential-well distortion and intra-beam scattering. In this paper, the bunch-lengthening due to the ring impedance is numerically investigated, and the result shows qualitative agreement with the result of an analysis performed using the bunch-length measurement. With the calculated longitudinal impedance, the instability threshold in the damping ring is estimated to be a bunch population of 3.3 x 10 10 by using both a Vlasov equation approach and a multi-particle tracking method.

  16. Variable elasticity of substituition in a discrete time Solow–Swan growth model with differential saving

    International Nuclear Information System (INIS)

    Brianzoni, Serena; Mammana, Cristiana; Michetti, Elisabetta

    2012-01-01

    Highlights: ► One dimensional piecewise smooth map: border collision bifurcations. ► Numerical simulations: complex dynamics. ► Ves production function in the solow–swan growth model and comparison with the ces production function. - Abstract: We study the dynamics shown by the discrete time neoclassical one-sector growth model with differential savings as in Bohm and Kaas while assuming VES production function in the form given by Revankar . It is shown that the model can exhibit unbounded endogenous growth despite the absence of exogenous technical change and the presence of non-reproducible factors if the elasticity of substitution is greater than one. We then consider parameters range related to non-trivial dynamics (i.e. the elasticity of substitution in less than one and shareholders save more than workers) and we focus on local and global bifurcations causing the transition to more and more complex asymptotic dynamics. In particular, as our map is non-differentiable in a subset of the states space, we show that border collision bifurcations occur. Several numerical simulations support the analysis.

  17. Accretion in Saturn's F Ring

    Science.gov (United States)

    Meinke, B. K.; Esposito, L. W.; Stewart, G.

    2012-12-01

    Saturn's F ring is the solar system's principal natural laboratory for direct observation of accretion and disruption processes. The ring resides in the Roche zone, where tidal disruption competes with self-gravity, which allows us to observe the lifecycle of moonlets. Just as nearby moons create structure at the B ring edge (Esposito et al. 2012) and the Keeler gap (Murray 2007), the F ring "shepherding" moons Prometheus and Pandora stir up ring material and create observably changing structures on timescales of days to decades. In fact, Beurle et al (2010) show that Prometheus makes it possible for "distended, yet gravitationally coherent clumps" to form in the F ring, and Barbara and Esposito (2002) predicted a population of ~1 km bodies in the ring. In addition to the observations over the last three decades, the Cassini Ultraviolet Imaging Spectrograph (UVIS) has detected 27 statistically significant features in 101 occultations by Saturn's F ring since July 2004. Seventeen of those 27 features are associated with clumps of ring material. Two features are opaque in occultation, which makes them candidates for solid objects, which we refer to as Moonlets. The 15 other features partially block stellar signal for 22 m to just over 3.7 km along the radial expanse of the occultation. Upon visual inspection of the occultation profile, these features resemble Icicles, thus we will refer to them as such here. The density enhancements responsible for such signal attenuations are likely due to transient clumping of material, evidence that aggregations of material are ubiquitous in the F ring. Our lengthy observing campaign reveals that Icicles are likely transient clumps, while Moonlets are possible solid objects. Optical depth is an indicator of clumping because more-densely aggregated material blocks more light; therefore, it is natural to imagine moonlets as later evolutionary stage of icicle, when looser clumps of material compact to form a feature that appears

  18. Confinement effect of laser ablation plume in liquids probed by self-absorption of C2 Swan band emission

    International Nuclear Information System (INIS)

    Sakka, Tetsuo; Saito, Kotaro; Ogata, Yukio H.

    2005-01-01

    The (0,0) Swan band of the C 2 molecules in a laser ablation plume produced on the surface of graphite target submerged in water was used as a probe to estimate the density of C 2 molecules in the plume. Observed emission spectra were reproduced excellently by introducing a self-absorption parameter to the theoretical spectral profile expected by a rotational population distribution at a certain temperature. The optical density of the ablation plume as a function of time was determined as a best-fit parameter by the quantitative fitting of the whole spectral profile. The results show high optical densities for the laser ablation plume in water compared with that in air. It is related to the plume confinement or the expansion, which are the important phenomena influencing the characteristics of laser ablation plumes in liquids

  19. Nonlinear analysis of ring oscillator circuits

    KAUST Repository

    Ge, Xiaoqing

    2010-06-01

    Using nonlinear systems techniques, we analyze the stability properties and synchronization conditions for ring oscillator circuits, which are essential building blocks in digital systems. By making use of its cyclic structure, we investigate local and global stability properties of an n-stage ring oscillator. We present a sufficient condition for global asymptotic stability of the origin and obtain necessity if the ring oscillator consists of identical inverter elements. We then give a synchronization condition for identical interconnected ring oscillators.

  20. Nonlinear analysis of ring oscillator circuits

    KAUST Repository

    Ge, Xiaoqing; Arcak, Murat; Salama, Khaled N.

    2010-01-01

    Using nonlinear systems techniques, we analyze the stability properties and synchronization conditions for ring oscillator circuits, which are essential building blocks in digital systems. By making use of its cyclic structure, we investigate local and global stability properties of an n-stage ring oscillator. We present a sufficient condition for global asymptotic stability of the origin and obtain necessity if the ring oscillator consists of identical inverter elements. We then give a synchronization condition for identical interconnected ring oscillators.

  1. Quality Assurance Project Plan for Verification of Sediment Ecotoxicity Assessment Ring(SEA Ring)

    Science.gov (United States)

    The objective of the verification is to test the efficacy and ability of the Sediment Ecotoxicity Assessment Ring (SEA Ring) to evaluate the toxicity of contaminants in the sediment, at the sediment-water interface, and WC to organisms that live in those respective environments.

  2. Dynamical Evolution of Ring-Satellite Systems

    Science.gov (United States)

    Ohtsuki, Keiji

    2005-01-01

    The goal of this research was to understand dynamical processes related to the evolution of size distribution of particles in planetary rings and application of theoretical results to explain features in the present rings of giant planets. We studied velocity evolution and accretion rates of ring particles in the Roche zone. We developed a new numerical code for the evolution of ring particle size distribution, which takes into account the above results for particle velocity evolution and accretion rates. We also studied radial diffusion rate of ring particles due to inelastic collisions and gravitational encounters. Many of these results can be also applied to dynamical evolution of a planetesimal disk. Finally, we studied rotation rates of moonlets and particles in planetary rings, which would influence the accretional evolution of these bodies. We describe our key accomplishments during the past three years in more detail in the following.

  3. Propellers in Saturn's rings

    Science.gov (United States)

    Sremcevic, M.; Stewart, G. R.; Albers, N.; Esposito, L. W.

    2013-12-01

    Theoretical studies and simulations have demonstrated the effects caused by objects embedded in planetary rings. Even if the objects are too small to be directly observed, each creates a much larger gravitational imprint on the surrounding ring material. These strongly depend on the mass of the object and range from "S" like propeller-shaped structures for about 100m-sized icy bodies to the opening of circumferential gaps as in the case of the embedded moons Pan and Daphnis and their corresponding Encke and Keeler Gaps. Since the beginning of the Cassini mission many of these smaller objects (~data from Cassini Ultraviolet Imaging Spectrograph (UVIS) and Imaging Science Subsystem (ISS) experiments. We show evidence that B ring seems to harbor two distinct populations of propellers: "big" propellers covering tens of degrees in azimuth situated in the densest part of B ring, and "small" propellers in less dense inner B ring that are similar in size and shape to known A ring propellers. The population of "big" propellers is exemplified with a single object which is observed for 5 years of Cassini data. The object is seen as a very elongated bright stripe (40 degrees wide) in unlit Cassini images, and dark stripe in lit geometries. In total we report observing the feature in images at 18 different epochs between 2005 and 2010. In UVIS occultations we observe this feature as an optical depth depletion in 14 out of 93 occultation cuts at corrotating longitudes compatible with imaging data. Combining the available Cassini data we infer that the object is a partial gap located at r=112,921km embedded in the high optical depth region of the B ring. The gap moves at Kepler speed appropriate for its radial location. Radial offsets of the gap locations in UVIS occultations are consistent with an asymmetric propeller shape. The asymmetry of the observed shape is most likely a consequence of the strong surface mass density gradient, as the feature is located at an edge between

  4. Cosmic rings from colliding galaxies

    Energy Technology Data Exchange (ETDEWEB)

    Mitton, S

    1976-11-18

    Research on two ring galaxies has led to the proposal of an interaction model to account for the rings. It is envisaged that this class of galaxy is created when a compact galaxy crashes through the disc of a spiral galaxy. The results of a spectroscopic investigation of the galaxy known as the Cartwheel and of another ring galaxy 11 NZ 4 are discussed. The general picture of ring galaxies which emerges from these studies of a massive starry nucleus with a necklace of emitting gas and some spokes and along the spin axis of the wheel a small companion galaxy that is devoid of interstellar gas. An explanation of these properties is considered.

  5. On Semiprime Noetherian PI-Rings

    OpenAIRE

    Chiba, Katsuo

    2000-01-01

    Let R be a semiprime Noetherian PI-ring and Q(R) the semisimple Artinian ring of fractions of R. We shall prove the following conditions are equivalent: (1) the Krull dimention of R is at most one, (2) Any ring between R and Q(R) is again right Noetherian, (3) Let a, b be central regular elements of Q(R). Then the subring R + aR[b] of Q(R) is right Noetherian.

  6. A 12-bit spectroscopy analog-to-digital converter type SAA (Successive Approximation type with channel width Averaging) intended for multichannel pulse height analyzer SWAN-1 based on IBM PC/XT/AT

    International Nuclear Information System (INIS)

    Borsuk, S.; Kulka, Z.

    1989-12-01

    A 12-bit spectroscopy analog-to-digital converter (ADC) type SAA (Successive Approximation type with channel width Averaging) intended for multichannel pulse height analyzer SWAN-1 based on IBM PC/XT/AT has been described. Design principles, specifications and measurements of a fundamental SAA-2 converter version are reported. Finally, two next versions of the converter with introduced modifications are discussed. 6 refs., 7 figs. (author)

  7. On zero divisor graph of unique product monoid rings over Noetherian reversible ring

    Directory of Open Access Journals (Sweden)

    Ebrahim Hashemi

    2016-02-01

    Full Text Available Let $R$ be an associative ring with identity and $Z^*(R$ be its set of non-zero zero divisors.  The zero-divisor graph of $R$, denoted by $Gamma(R$, is the graph whose vertices are the non-zero  zero-divisors of  $R$, and two distinct vertices $r$ and $s$ are adjacent if and only if $rs=0$ or $sr=0$.  In this paper, we bring some results about undirected zero-divisor graph of a monoid ring over reversible right (or left Noetherian ring $R$. We essentially classify the diameter-structure of this graph and show that $0leq mbox{diam}(Gamma(Rleq mbox{diam}(Gamma(R[M]leq 3$. Moreover, we give a characterization for the possible diam$(Gamma(R$ and diam$(Gamma(R[M]$, when $R$ is a reversible Noetherian ring and $M$ is a u.p.-monoid. Also, we study relations between the girth of $Gamma(R$ and that of $Gamma(R[M]$.

  8. Imidazolopiperazines (IPZ) kill both rings and dormant rings in wild type and K13 artemisinin resistant Plasmodium falciparum in vitro.

    Science.gov (United States)

    Dembele, Laurent; Gupta, Devendra Kumar; Lim, Michelle Yi-Xiu; Ang, Xiaoman; Selva, Jeremy J; Chotivanich, Kesinee; Nguon, Chea; Dondorp, Arjen M; Bonamy, Ghislain M C; Diagana, Thierry T; Bifani, Pablo

    2018-03-12

    Artemisinin (ART) resistance has spread through Southeast Asia, posing serious threat to the control and elimination of malaria. ART resistance has been associated with mutations in the Plasmodium falciparum kelch-13 ( Pfk13 ) propeller domain. Phenotypically, ART resistance is defined as delayed parasite clearance in patients' due to the reduced susceptibility of early ring-stage parasites to the active metabolite of ART dihydroartemisinin (DHA). Early rings can enter a state of quiescence upon DHA exposure and resume growth in its absence. These quiescent rings are referred to as dormant rings or DHA-pretreated rings (called here dormant rings). The imidazolopiperazine (IPZ) is a novel class of antimalarial drugs, which has demonstrated efficacy in early clinical trials. Here, we characterized the stage of action of IPZ GNF179 and evaluated its activity against rings and dormant rings in wild type and ART resistant parasites. Unlike DHA, GNF179 does not induce dormancy. We show that GNF179 is more rapidly cidal against schizonts than ring and trophozoite stages. However, with 12 hours exposure, the compound effectively kills rings and dormant rings of both susceptible and ART resistant parasites within 72 hours. We further demonstrate that in combination with ART, GNF179 effectively prevent recrudescence of dormant rings including those bearing pfk13 propeller mutations. Copyright © 2018 Dembele et al.

  9. Complete snake and rotator schemes for spin polarization in proton rings and large electron rings

    International Nuclear Information System (INIS)

    Steffen, K.

    1983-11-01

    In order to maintain spin polarization in proton rings and large electron rings, some generalized Siberian Snake scheme may be required to make the spin tune almost independent of energy and thus avoid depolarizing resonances. The practical problem of finding such schemes that, at reasonable technical effort, can be made to work over large energy ranges has been addressed before and is here revisited in a broadened view and with added new suggestions. As a result, possibly optimum schemes for electron rings (LEP) and proton rings are described. In the proposed LEP scheme, spin rotation is devised such that, at the interaction points, the spin direction is longitudinal as required for experiments. (orig.)

  10. Koffka's Ring Effect Depends on Thickness, Not Continuity

    OpenAIRE

    Abigail E. Huang; Alice J. Hon; Eric L. Altschuler

    2007-01-01

    More than 70 years ago Gestalt psychologist Kurt Koffka described a fascinating effect1,2: When a contiguous grey ring is placed on a background half of one shade of grey (different from the ring) and half of another shade of grey, the ring appears to be a homogenous. However, if the ring is slightly divided, now the two halves of the ring appear different shades of grey with the half of the ring on the darker background appearing lighter than the half of the ring on the darker background. Th...

  11. Almost ring theory

    CERN Document Server

    2003-01-01

    This book develops thorough and complete foundations for the method of almost etale extensions, which is at the basis of Faltings' approach to p-adic Hodge theory. The central notion is that of an "almost ring". Almost rings are the commutative unitary monoids in a tensor category obtained as a quotient V-Mod/S of the category V-Mod of modules over a fixed ring V; the subcategory S consists of all modules annihilated by a fixed ideal m of V, satisfying certain natural conditions. The reader is assumed to be familiar with general categorical notions, some basic commutative algebra and some advanced homological algebra (derived categories, simplicial methods). Apart from these general prerequisites, the text is as self-contained as possible. One novel feature of the book - compared with Faltings' earlier treatment - is the systematic exploitation of the cotangent complex, especially for the study of deformations of almost algebras.

  12. IAG ring test animal proteins 2014

    NARCIS (Netherlands)

    Raamsdonk, van L.W.D.; Pinckaers, V.G.Z.; Scholtens-Toma, I.M.J.; Prins, T.W.; Voet, van der H.; Vliege, J.J.M.

    2014-01-01

    A ring test was organized for the detection of animal proteins in animal feed by microscopy in the framework of the annual ring tests of the IAG – International Association for Feeding stuff Analysis, Section Feeding stuff Microscopy. The aim of the ring study was to provide the participants

  13. IAG ring test animal proteins 2015

    NARCIS (Netherlands)

    Raamsdonk, van L.W.D.; Rhee, van de N.E.; Scholtens-Toma, I.M.J.; Prins, T.W.; Vliege, J.J.M.; Pinckaers, V.G.Z.

    2015-01-01

    A ring test was organized for the detection of animal proteins in animal feed by microscopy in the framework of the annual ring tests of the IAG - International Association for Feeding stuff Analysis, Section Feeding stuff Microscopy. The organizer of the ring test was RIKILT - Wageningen UR, The

  14. IAG ring test animal proteins 2013

    NARCIS (Netherlands)

    Raamsdonk, van L.W.D.; Pinckaers, V.G.Z.; Scholtens-Toma, I.M.J.; Prins, T.W.; Vliege, J.J.M.

    2013-01-01

    A ring test was organized for the detection of animal proteins in animal feed by microscopy in the framework of the annual ring tests of the IAG - International Association for Feeding stuff Analysis, Section Feeding stuff Microscopy. The organizer of the the ring study was to provide the

  15. Cooling rings for TeV colliders

    International Nuclear Information System (INIS)

    Palmer, R.B.

    1985-02-01

    Consideration is given to quantum fluctuations, intra beam scattering, cooling rates, and ring acceptance in order to see if one can obtain a normalized emittance of 10 -8 in any plausible cooling ring. It is concluded that only a small gain is obtained by varying the partition functions, but a very significant gain is made by using higher bending fields. The ring is found to get bigger if the magnet apertures are increased. The ring diameter is found to increase if the momentum spread of the beam is reduced. It is shown that the power can be reduced by allowing a high beamstrahlung energy loss resulting in higher current in the cooling ring. Parameters are also given for a 10 -7 m radian emittance case

  16. Distribution of the FMR1 gene in females by race/ethnicity: women with diminished ovarian reserve versus women with normal fertility (SWAN study).

    Science.gov (United States)

    Pastore, Lisa M; Young, Steven L; Manichaikul, Ani; Baker, Valerie L; Wang, Xin Q; Finkelstein, Joel S

    2017-01-01

    To study whether reported, but inconsistent, associations between the FMR1 CGG repeat lengths in the intermediate, high normal, or low normal range differentiate women diagnosed with diminished ovarian reserve (DOR) from population controls and whether associations vary by race/ethnic group. Case-control study. Academic and private fertility clinics. DOR cases (n = 129; 95 Whites, 22 Asian, 12 other) from five U.S. fertility clinics were clinically diagnosed, with regular menses and no fragile X syndrome family history. Normal fertility controls (n = 803; 386 Whites, 219 African-Americans, 102 Japanese, 96 Chinese) from the United States-based SWAN Study had one or more menstrual period in the 3 months pre-enrollment, one or more pregnancy, no history of infertility or hormone therapy, and menopause ≥46 years. Previously, the SWAN Chinese and Japanese groups had similar FMR1 CGG repeat lengths, thus they were combined. None. FMR1 CGG repeat lengths. Median CGG repeats were nearly identical by case/control group. DOR cases had fewer CGG repeats in the shorter FMR1 allele than controls among Whites, but this was not significant among Asians. White cases had fewer CGG repeats in the shorter allele than Asian cases. No significant differences were found in the high normal/intermediate range between cases and controls or by race/ethnic group within cases in the longer allele. This study refutes prior reports of an association between DOR and high normal/intermediate repeats and confirms an association between DOR and low normal repeats in Whites. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  17. Dipole Magnets for the LHeC Ring-Ring Option

    CERN Document Server

    Tommasini, D; Chritin, R

    2012-01-01

    The Ring-Ring option of a Large Hadron electron Collider (LHeC) requires 3080 bending magnets, 5.35-meter-long each providing a magnetic field ranging from 0.0127 T at 10 GeV to 0.0763 T at 60 GeV. Main issues in the design of these magnets are the very low injection field, constituting a challenge in achieving a satisfactory field reproducibility from cycle to cycle, and the required compactness to fit in the existing LHC tunnel. This paper describes and discusses a design meeting these requirements, together with its experimental validation by the manufacture and measurement of a 400-mm-long magnet model.

  18. The multi-bend achromat storage rings

    Energy Technology Data Exchange (ETDEWEB)

    Eriksson, Mikael [MAX IV Laboratory Ole Römers v. 1 22100 Lund Sweden (Sweden)

    2016-07-27

    Not very long ago, the 3{sup rd} generation storage ring technology was judged as mature. Most of the 3{sup rd} generation storage rings used the Double-Bend Achromat (DBA) or Triple-Bend Achromat (TBA) concepts. It was however a well-known fact that increasing the number of magnet cells in the rings is a powerful way of decreasing the electron beam emittance and thus the source brilliance, but at the penalty of increasing the size and cost of the rings. Preserving the Dynamic Aperture (DA) in the rings became also an issue when increasing the number of magnet cells. The Multi-Bend Achromat (MBA) concept, including a miniaturization of the ring elements, has now drastically changed the picture. The MBA rings, now in construction or being planned, offer orders of magnitudes higher brilliance than rings of conventional designs. Several light sources around the world are now implementing or planning to implement this MBA concept. This article touches on the science drivers for higher brilliance. We will then describe the MBA concept with its advantages as well as its challenges. A short survey of the MBA activity around the world will also be presented. The author apologies for focusing on the MAX IV project regarding technical solutions. This is motivated by that MAX IV is the facility he knows best and it might be regarded as a fore-runner for the MBA concept.

  19. The multi-bend achromat storage rings

    International Nuclear Information System (INIS)

    Eriksson, Mikael

    2016-01-01

    Not very long ago, the 3"r"d generation storage ring technology was judged as mature. Most of the 3"r"d generation storage rings used the Double-Bend Achromat (DBA) or Triple-Bend Achromat (TBA) concepts. It was however a well-known fact that increasing the number of magnet cells in the rings is a powerful way of decreasing the electron beam emittance and thus the source brilliance, but at the penalty of increasing the size and cost of the rings. Preserving the Dynamic Aperture (DA) in the rings became also an issue when increasing the number of magnet cells. The Multi-Bend Achromat (MBA) concept, including a miniaturization of the ring elements, has now drastically changed the picture. The MBA rings, now in construction or being planned, offer orders of magnitudes higher brilliance than rings of conventional designs. Several light sources around the world are now implementing or planning to implement this MBA concept. This article touches on the science drivers for higher brilliance. We will then describe the MBA concept with its advantages as well as its challenges. A short survey of the MBA activity around the world will also be presented. The author apologies for focusing on the MAX IV project regarding technical solutions. This is motivated by that MAX IV is the facility he knows best and it might be regarded as a fore-runner for the MBA concept.

  20. Ring wormholes via duality rotations

    Directory of Open Access Journals (Sweden)

    Gary W. Gibbons

    2016-09-01

    Full Text Available We apply duality rotations and complex transformations to the Schwarzschild metric to obtain wormhole geometries with two asymptotically flat regions connected by a throat. In the simplest case these are the well-known wormholes supported by phantom scalar field. Further duality rotations remove the scalar field to yield less well known vacuum metrics of the oblate Zipoy–Voorhees–Weyl class, which describe ring wormholes. The ring encircles the wormhole throat and can have any radius, whereas its tension is always negative and should be less than −c4/4G. If the tension reaches the maximal value, the geometry becomes exactly flat, but the topology remains non-trivial and corresponds to two copies of Minkowski space glued together along the disk encircled by the ring. The geodesics are straight lines, and those which traverse the ring get to the other universe. The ring therefore literally produces a hole in space. Such wormholes could perhaps be created by negative energies concentrated in toroidal volumes, for example by vacuum fluctuations.

  1. Evidence for Quantisation in Planetary Ring Systems

    OpenAIRE

    WAYTE, RICHARD

    2017-01-01

    Absolute radial positions of the main features in Saturn's ring system have been calculated by adapting the quantum theory of atomic spectra. Fine rings superimposed upon broad rings are found to be covered by a harmonic series of the form N α A(r)1/2, where N and A are integers. Fourier analysis of the ring system shows that the spectral amplitude fits a response profile which is characteristic of a resonant system. Rings of Jupiter, Uranus and Neptune also obey the same rules. Involvement o...

  2. Multiplication modules over non-commutative rings

    International Nuclear Information System (INIS)

    Tuganbaev, A A

    2003-01-01

    It is proved that each submodule of a multiplication module over a regular ring is a multiplicative module. If A is a ring with commutative multiplication of right ideals, then each projective right ideal is a multiplicative module, and a finitely generated A-module M is a multiplicative module if and only if all its localizations with respect to maximal right ideals of A are cyclic modules over the corresponding localizations of A. In addition, several known results on multiplication modules over commutative rings are extended to modules over not necessarily commutative rings

  3. Status of the SLC damping rings

    International Nuclear Information System (INIS)

    Hutton, A.M.; Davies-White, W.A.; Delahaye, J.P.

    1985-06-01

    Electron beams of full design energy 1.21 GeV and nearly full design intensity 4 x 10 10 particles/pulse (design 5 x 10 10 ) have been extracted from the Stanford Linac and successfully stored in the electron damping ring. Beams of less intensity have been extracted from the ring and reinjected into the Linac. The present intensity limits are not thought to be fundamental. The operating experience with the electron ring and the status of the construction of the positron ring will be discussed. 11 refs., 1 fig., 2 tabs

  4. Characterization of heterocyclic rings through quantum chemical topology.

    Science.gov (United States)

    Griffiths, Mark Z; Popelier, Paul L A

    2013-07-22

    Five-membered rings are found in a myriad of molecules important in a wide range of areas such as catalysis, nutrition, and drug and agrochemical design. Systematic insight into their largely unexplored chemical space benefits from first principle calculations presented here. This study comprehensively investigates a grand total of 764 different rings, all geometry optimized at the B3LYP/6-311+G(2d,p) level, from the perspective of Quantum Chemical Topology (QCT). For the first time, a 3D space of local topological properties was introduced, in order to characterize rings compactly. This space is called RCP space, after the so-called ring critical point. This space is analogous to BCP space, named after the bond critical point, which compactly and successfully characterizes a chemical bond. The relative positions of the rings in RCP space are determined by the nature of the ring scaffold, such as the heteroatoms within the ring or the number of π-bonds. The summed atomic QCT charges of the five ring atoms revealed five features (number and type of heteroatom, number of π-bonds, substituent and substitution site) that dictate a ring's net charge. Each feature independently contributes toward a ring's net charge. Each substituent has its own distinct and systematic effect on the ring's net charge, irrespective of the ring scaffold. Therefore, this work proves the possibility of designing a ring with specific properties by fine-tuning it through manipulation of these five features.

  5. Single photon emission and quantum ring-cavity coupling in InAs/GaAs quantum rings

    International Nuclear Information System (INIS)

    Gallardo, E; Nowak, A K; Sanvitto, D; Meulen, H P van der; Calleja, J M; MartInez, L J; Prieto, I; Alija, A R; Granados, D; Taboada, A G; GarcIa, J M; Postigo, P A; Sarkar, D

    2010-01-01

    Different InAs/GaAs quantum rings embedded in a photonic crystal microcavity are studied by quantum correlation measurements. Single photon emission, with g (2) (0) values around 0.3, is demonstrated for a quantum ring not coupled to the microcavity. Characteristic rise-times are found to be longer for excitons than for biexcitons, resulting in the time asymmetry of the exciton-biexciton cross-correlation. No antibunching is observed in another quantum ring weakly coupled to the microcavity.

  6. Macrodinâmicas de crescimento em uma economia Solow-Swan com migração: uma abordagem de jogos evolucionários

    Directory of Open Access Journals (Sweden)

    Jaylson Jair da Silveira

    2007-06-01

    Full Text Available Introduz-se no modelo Solow-Swan a migração como uma dinâmica satisficing. A conclusão geral está de acordo com a abordagem tradicional: as características da economia doméstica no estado estacionário dependem do saldo migratório líquido. Entretanto, novos resultados são obtidos. Em primeiro lugar, a economia doméstica não pode trilhar sua trajetória de crescimento equilibrado como uma perpétua receptora/fornecedora líquida de mão-de-obra. Em segundo lugar, caso ela apresente em seu estado estacionário um saldo migratório líquido nulo, o tamanho de sua população depende das condições iniciais (path dependence. Finalmente, demonstra-se que a introdução de um "efeito congestionamento" da imigração líquida abre a possibilidade de existência simultânea da economia doméstica e do resto do mundo.Migration as a satisficing dynamics is introduced into the Solow-Swan model. The general conclusion is in agreement with that of the traditional approach: the steady-state features of domestic economy depends on the net migration rate. However, there are new outcomes. The domestic economy cannot be a perpetual host/supplier of migrants in its balanced growth path. If the domestic economy shows a zero-net migration rate in the steady state, then the population level will depend on the initial conditions (path dependence. A "congestion effect" resulting from net migration opens the possibility of simultaneous existence of the domestic economy and the rest of the world.

  7. Powder metallurgy ferrous synchronizer ring with brass-based friction layer; Tetsu-do niso shoketsu synchronize ring no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Okajima, H; Yoshikawa, K; Miyajima, K; Sugiyama, M [Toyota Motor Corp., Aichi (Japan); Nakamura, M; Ito, M [Japan Powder Metallurgy Co. Ltd., Tokyo (Japan)

    1997-10-01

    Synchronizer rings for manual transmissions are generally made of brass or molybdenum coated brass. Powder metallurgy (PM) synchronizer ring was developed for the purpose of high performance and cost reduction. This synchronizer ring consists of the high strength PM ferrous ring that needs neither special densification nor heat treatment, and it has the brass-based friction layer. New joining technique was required because of that shape and two different materials. Powder of copper-phosphorus alloy are admixed with the friction material. While sintering, that melt and migrate to the interface. Then the friction layer and the ferrous ring are joined tightly. 7 refs., 9 figs., 6 tabs.

  8. Komatiites and nickel sulphide orebodies of the Black Swan area, Yilgarn Craton, Western Australia. 1. Petrology and volcanology of host rocks

    Science.gov (United States)

    Hill, R. E. T.; Barnes, S. J.; Dowling, S. E.; Thordarson, T.

    2004-11-01

    The Black Swan Succession is a bimodal association of dacitic and komatiitic volcanic rocks located about 50 km NNE of Kalgoorlie, within the 2.7-Ga Eastern Goldfields greenstone province of the Yilgarn Craton. The komatiite stratigraphy comprises a steep dipping, east facing package about 700 m in maximum thickness and about 2.5 km in strike length (Fig. 1), which hosts a number of economically exploitable Ni sulphide orebodies including the Silver Swan massive ore shoot (approximately half a million tonnes at about 10.5% Ni). The sequence can be subdivided into a Lower Felsic Unit, comprising coherent and autobrecciated facies of multiple dacite lava flows; an upper Eastern and lower Western Ultramafic Unit, each showing marked lateral facies variation, and an Upper Felsic Unit coeval with the Eastern Ultramafic Unit. The komatiite sequence has been metamorphosed at sub-greenschist facies in the presence of high proportions of CO2-rich fluid, giving rise to pervasive talc carbonate and talc carbonate quartz assemblages, with extensive preservation of pseudomorphed igneous textures. Cores of lizardite serpentinite are present in the thickest parts of the ultramafic succession. The degree of penetrative deformation is generally very low, and original stratigraphic relationships are largely intact in much of the sequence. The Eastern Ultramafic Unit and Western Ultramafic Unit are interpreted as components of a single large komatiite flow field, representing overlapping stages in the emplacement of a series of distributory lava pathways and flanking sheet flows. The Western Ultramafic Unit which hosts the bulk of the high-grade massive and disseminated ores is a sequence dominated by coarse-grained olivine cumulates, 2 km wide and up to 500 m thick, with major magma pathways represented by thick, homogenous olivine mesocumulate piles at its northern and southern ends: respectively 400 and 200 m thick. The sequence between the two major pathways consists of olivine

  9. Vortex Ring Dynamics in Radially Confined Domains

    Science.gov (United States)

    Stewart, Kelley; Niebel, Casandra; Jung, Sunghwan; Vlachos, Pavlos

    2010-11-01

    Vortex ring dynamics have been studied extensively in semi-infinite quiescent volumes. However, very little is known about vortex-ring formation in wall-bounded domains where vortex wall interaction will affect both the vortex ring pinch-off and propagation velocity. This study addresses this limitation and studies vortex formation in radially confined domains to analyze the affect of vortex-ring wall interaction on the formation and propagation of the vortex ring. Vortex rings were produced using a pneumatically driven piston cylinder arrangement and were ejected into a long cylindrical tube which defined the confined downstream domain. A range of confinement domains were studied with varying confinement diameters Velocity field measurements were performed using planar Time Resolved Digital Particle Image Velocimetry (TRDPIV) and were processed using an in-house developed cross-correlation PIV algorithm. The experimental analysis was used to facilitate the development of a theoretical model to predict the variations in vortex ring circulation over time within confined domains.

  10. The Conversion of Wiswesser Line Notations to Ring Codes. I. The Conversion of Ring Systems

    Science.gov (United States)

    Granito, Charles E.; And Others

    1972-01-01

    The computerized conversion of Wiswesser Line Notations to Ring Codes, using a two-part approach, and the set of computer programs generated for the conversion of ring systems are described. (9 references) (Author)

  11. Spatial transmission of H5N6 highly pathogenic avian influenza viruses among wild birds in Ibaraki Prefecture, Japan, 2016-2017.

    Science.gov (United States)

    Tsunekuni, Ryota; Yaguchi, Yuji; Kashima, Yuki; Yamashita, Kaoru; Takemae, Nobuhiro; Mine, Junki; Tanikawa, Taichiro; Uchida, Yuko; Saito, Takehiko

    2018-05-01

    From 29 November 2016 to 24 January 2017, sixty-three cases of H5N6 highly pathogenic avian influenza virus (HPAIV) infections were detected in wild birds in Ibaraki Prefecture, Japan. Here, we analyzed the genetic, temporal, and geographic correlations of these 63 HPAIVs to elucidate their dissemination throughout the prefecture. Full-genome sequence analysis of the Ibaraki isolates showed that 7 segments (PB2, PB1, PA, HA, NP, NA, NS) were derived from G1.1.9 strains while the M segment was from G1.1 strains; both groups of strains circulated in south China. Pathological studies revealed severe systemic infection in dead swans (the majority of dead birds and the only species necropsied), thus indicating high susceptibility to H5N6 HPAIVs. Coalescent phylogenetic analysis using the 7 G1.1.9-derived segments enabled detailed analysis of the short-term evolution of these highly homologous HPAIVs. This analysis revealed that the H5N6 HPAIVs isolated from wild birds in Ibaraki Prefecture were divided into 7 groups. Spatial analysis demonstrated that most of the cases concentrated around Senba Lake originated from a single source, and progeny viruses were transmitted to other locations after the infection expanded in mute swans. In contrast, within just a 5-km radius of the area in which cases were concentrated, three different intrusions of H5N6 HPAIVs were evident. Multi-segment analysis of short-term evolution showed that not only was the invading virus spread throughout Ibaraki Prefecture but also that, despite the small size of this region, multiple invasions had occurred during winter 2016-2017.

  12. The Saturnian rings

    International Nuclear Information System (INIS)

    Alfven, H.

    1975-09-01

    The structure of the Saturnian rings is traditionally believed to be due to resonances caused by Mimas (and possibly other satellites). It is shown that both theoretical and observational evidence rule out this interpretation. The increased observational accuracy on one hand and the increased understanding of the cosmogonic processes on the other makes it possible to explain the structure of the ring system as a product of condensation from a partially corotating plasma. In certain respects the agreement between theory and observations is about 1%. (Auth.)

  13. Hubble again views Saturn's Rings Edge-on

    Science.gov (United States)

    1995-01-01

    Saturn's magnificent ring system is seen tilted edge-on -- for the second time this year -- in this NASA Hubble Space Telescope picture taken on August 10, 1995, when the planet was 895 million miles (1,440 million kilometers) away. Hubble snapped the image as Earth sped back across Saturn's ring plane to the sunlit side of the rings. Last May 22, Earth dipped below the ring plane, giving observers a brief look at the backlit side of the rings. Ring-plane crossing events occur approximately every 15 years. Earthbound observers won't have as good a view until the year 2038. Several of Saturn's icy moons are visible as tiny starlike objects in or near the ring plane. They are from left to right, Enceladus, Tethys, Dione and Mimas. 'The Hubble data shows numerous faint satellites close to the bright rings, but it will take a couple of months to precisely identify them,' according to Steve Larson (University of Arizona). During the May ring plane crossing, Hubble detected two, and possibly four, new moons orbiting Saturn. These new observations also provide a better view of the faint E ring, 'to help determine the size of particles and whether they will pose a collision hazard to the Cassini spacecraft,' said Larson. The picture was taken with Hubble's Wide Field Planetary Camera 2 in wide field mode. This image is a composite view, where a long exposure of the faint rings has been combined with a shorter exposure of Saturn's disk to bring out more detail. When viewed edge-on, the rings are so dim they almost disappear because they are very thin -- probably less than a mile thick.The Wide Field/Planetary Camera 2 was developed by the Jet Propulsion Laboratory and managed by the Goddard Spaced Flight Center for NASA's Office of Space Science.This image and other images and data received from the Hubble Space Telescope are posted on the World Wide Web on the Space Telescope Science Institute home page at URL http://oposite.stsci.edu/pubinfo/

  14. Vaginal rings for delivery of HIV microbicides.

    Science.gov (United States)

    Malcolm, R Karl; Fetherston, Susan M; McCoy, Clare F; Boyd, Peter; Major, Ian

    2012-01-01

    Following the successful development of long-acting steroid-releasing vaginal ring devices for the treatment of menopausal symptoms and contraception, there is now considerable interest in applying similar devices to the controlled release of microbicides against HIV. In this review article, the vaginal ring concept is first considered within the wider context of the early advances in controlled-release technology, before describing the various types of ring device available today. The remainder of the article highlights the key developments in HIV microbicide-releasing vaginal rings, with a particular focus on the dapivirine ring that is presently in late-stage clinical testing.

  15. The ring plus project: safety and acceptability of vaginal rings that protect women from unintended pregnancy.

    Science.gov (United States)

    Schurmans, Céline; De Baetselier, Irith; Kestelyn, Evelyne; Jespers, Vicky; Delvaux, Thérèse; Agaba, Stephen K; van Loen, Harry; Menten, Joris; van de Wijgert, Janneke; Crucitti, Tania

    2015-04-10

    Research is ongoing to develop multipurpose vaginal rings to be used continuously for contraception and to prevent Human Immunodeficiency Virus (HIV) infection. Contraceptive vaginal rings (CVRs) are available in a number of countries and are most of the time used intermittently i.e. three weeks out of a 4-week cycle. Efficacy trials with a dapivirine-containing vaginal ring for HIV prevention are ongoing and plans to develop multi-purpose vaginal rings for prevention of both HIV and pregnancy have been elaborated. In contrast with the CVRs, multi-purpose vaginal rings will have to be used continuously. Women who continuously use a CVR will no longer have menses. Furthermore, some safety aspects of CVR use have never been studied in-depth in the past, such as the impact of the vaginal ring on the vaginal microbiota, biofilm formation and induction of inflammation. We studied acceptability and these novel aspects of safety in Rwandan women. Although significant progress has been made over the past decade, Rwanda still has a high unmet need for contraception (with 47% unplanned births) and a generalized HIV epidemic, and CVRs are not yet available. We will conduct an open label, single centre, randomized controlled trial. A total of 120 HIV-negative women will be randomized to intermittent CVR use (to allow menstruation) or continuous CVR use. Women will be followed for a maximum of 14 weeks. In parallel, we will conduct a qualitative study using in-depth interview and focus group discussion methodology. In addition to evaluating the safety and acceptability of intermittent and continuous CVR use in Rwandan women, we hope that our findings will inform the development of future multipurpose vaginal rings, will prepare Rwandan study populations for future clinical trials of multipurpose vaginal rings, and will pave the way for introduction of CVRs on African markets. Clinicaltrials.gov NCT01796613 . Registered 14 February 2013.

  16. Common pass decentered annular ring resonator

    Energy Technology Data Exchange (ETDEWEB)

    Holmes, D. A.; Waite, T. R.

    1985-04-30

    An optical resonator having an annular cylindrical gain region for use in a chemical laser or the like in which two ring-shaped mirrors having substantially conical reflecting surfaces are spaced apart along a common axis of revolution of the respective conical surfaces. A central conical mirror reflects incident light directed along said axis radially outwardly to the reflecting surface of a first one of the ring-shaped mirrors. The radial light rays are reflected by the first ring mirror to the second ring mirror within an annular cylindrical volume concentric with said common axis and forming a gain region. Light rays impinging on the second ring mirror are reflected to diametrically opposite points on the same conical mirror surfaces and back to the first ring mirror through the same annular cylindrical volume. The return rays are then reflected by the conical mirror surface of the first ring mirror back to the central conical mirror. The mirror surfaces are angled such that the return rays are reflected back along the common axis by the central mirror in a concentric annular cylindrical volume. A scraper mirror having a central opening centered on said axis and an offset opening reflects all but the rays passing through the two openings in an output beam. The rays passing through the second opening are reflected back through the first opening to provide feedback.

  17. Tritium concentrations in tree ring cellulose

    International Nuclear Information System (INIS)

    Kaji, Toshio; Momoshima, Noriyuki; Takashima, Yoshimasa.

    1989-01-01

    Measurements of tritium (tissue bound tritium; TBT) concentration in tree rings are presented and discussed. Such measurement is expected to provide a useful means of estimating the tritium level in the environment in the past. The concentration of tritium bound in the tissue (TBT) in a tree ring considered to reflect the environmental tritium level in the area at the time of the formation of the ring, while the concentration of tritium in the free water in the tissue represents the current environmental tritium level. First, tritium concentration in tree ring cellulose sampled from a cedar tree grown in a typical environment in Fukuoka Prefecture is compared with the tritium concentration in precipitation in Tokyo. Results show that the year-to-year variations in the tritium concentration in the tree rings agree well with those in precipitation. The maximum concentration, which occurred in 1963, is attibuted to atmospheric nuclear testing which was performed frequently during the 1961 - 1963 period. Measurement is also made of the tritium concentration in tree ring cellulose sampled from a pine tree grown near the Isotope Center of Kyushu University (Fukuoka). Results indicate that the background level is higher probably due to the release of tritium from the facilities around the pine tree. Thus, measurement of tritium in tree ring cellulose clearly shows the year-to-year variation in the tritium concentration in the atmosphere. (N.K.)

  18. Inorganic glass ceramic slip rings

    Science.gov (United States)

    Glossbrenner, E. W.; Cole, S. R.

    1972-01-01

    Prototypes of slip rings have been fabricated from ceramic glass, a material which is highly resistant to deterioration due to high temperature. Slip ring assemblies were not structurally damaged by mechanical tests and performed statisfactorily for 200 hours.

  19. Translational velocity oscillations of piston generated vortex rings

    Science.gov (United States)

    Kumar, Manoj; Arakeri, J. H.; Shankar, P. N.

    1995-11-01

    Experimental results are presented that show that the translational velocities of piston generated vortex rings often undergo oscillations, similar to those recently discovered for drop generated rings. An attempt has been made to minimize uncertainties by utilizing both dye and hydrogen bubbles for visualization and carefully repeating measurements on the same ring and on different realizations under the same nominal piston conditions. The results unambiguously show that under most conditions, both for laminar and turbulent rings and for rings generated from pipes and orifices, the oscillations are present. The present results, together with the earlier results on drop generated rings, give support to the view that translational velocity oscillations are probably an inherent feature of translating vortex ring fields.

  20. Seco-B-Ring Steroidal Dienynes with Aromatic D Ring: Design, Synthesis and Biological Evaluation

    Directory of Open Access Journals (Sweden)

    Marcin Szybinski

    2017-10-01

    Full Text Available Continuing our structure-activity studies on the vitamin D analogs with the altered intercyclic seco-B-ring fragment, we designed compounds possessing dienyne system conjugated with the benzene D ring. Analysis of the literature data and the docking experiments seemed to indicate that the target compounds could mimic the ligands with a good affinity to the vitamin D receptor (VDR. Multi-step synthesis of the C/D-ring building block of the tetralone structure was achieved and its enol triflate was coupled with the known A-ring fragments, possessing conjugated enyne moiety, using Sonogashira protocol. The structures of the final products were confirmed by NMR, UV and mass spectroscopy. Their binding affinities for the full-length human VDR were determined and it was established that compound substituted at C-2 with exomethylene group showed significant binding to the receptor. This analog was also able to induce monocytic differentiation of HL-60 cells.

  1. Saturn's Ring: Pre-Cassini Status and Mission Goals

    Science.gov (United States)

    Cuzzi, Jeff N.; DeVincenzi, Donald L. (Technical Monitor)

    1999-01-01

    In November 1980, and again in August 1981, identical Voyager spacecraft flew through the Saturn system, changing forever the way we think about planetary rings. Although Saturn's rings had been the only known ring system for three centuries, a ring system around Uranus had been discovered by stellar occultations from Earth in 1977, and the nearly transparent ring of Jupiter was imaged by Voyager in 1979 (the presence of material there had been inferred from charged particle experiments on Pioneer 10 and 11 several years earlier). While Saturn had thus temporarily lost its uniqueness as having the only ring system, with Voyager it handily recaptured the role of having the most fascinating one. The Voyager breakthroughs included spiral density and bending waves such as cause galactic structure; ubiquitous fine-scale radial 'irregular' structure, with the appearance of record-grooves; regional and local variations in particle color; complex, azimuthally variable ring structure; empty gaps in the rings, some containing very regular, sharp-edged, elliptical rings and one containing both a small moonlet and incomplete arcs of dusty material; and shadowy 'spokes' that flicker across the main rings. One of the paradigm shifts of this period was the realization that many aspects of planetary rings, and even the ring systems themselves, could be 'recent' on geological timescales. These early results are reviewed and summarized in the Arizona Space Science series volumes 'Saturn'. (An excellent review of ring dynamics at a formative stage is by Goldreich and Tremaine.) From the mid 1980's to the time of this writing, progress has been steady, while at a less heady pace, and some of the novel ring properties revealed by Voyager 1 and 2 are beginning to be better understood. It is clearly impossible to cite, much less review, every advance over the last decade; however, below we summarize the main advances in understanding of Saturn's rings since the mid 1980's, in the context

  2. Rings Related to Special Atoms | France-Jackson | Quaestiones ...

    African Journals Online (AJOL)

    Abstract unavailable at this time... Mathematics Subject Classification (1991): 16A21, 16A12 Keywords: ring, special atoms, atoms, *k-ring, prime ring, *-ring, Jacobson, artinia, essential extension, homomorphic image, ideals. Quaestiones Mathematicae 24(1) 2001, 105–109 ...

  3. Using Ring Strain to Control 4π-Electrocyclization Reactions: Torquoselectivity in Ring Closing of Medium-Ring Dienes and Ring Opening of Bicyclic Cyclobutenes.

    Science.gov (United States)

    Boon, Byron A; Green, Aaron G; Liu, Peng; Houk, K N; Merlic, Craig A

    2017-05-05

    Syntheses of strained cyclic dienes were accomplished via palladium(II)-catalyzed oxidative cyclizations of terminal bis(vinylboronate esters). The reactions generate strained (E,E)-1,3-dienes that undergo spontaneous 4π-electrocyclizations to form bicyclic cyclobutenes. Formation of the cyclobutenes is driven by the strain in the medium-ring (E,E)-1,3-diene intermediate. Thermal ring openings of the cyclobutenes give (Z,Z)-1,3-diene products, again for thermodynamic reasons. DFT calculations verified the thermodynamic versus kinetic control of the reactions, and kinetic studies are in excellent agreement with the calculated energy changes. An extension of the tandem coupling/4π-electrocyclization pathway was demonstrated by a palladium(II)-catalyzed oxidative homocoupling/8π-electrocyclization cascade.

  4. Ring Avulsion Injuries: A Systematic Review.

    Science.gov (United States)

    Bamba, Ravinder; Malhotra, Gautam; Bueno, Reuben A; Thayer, Wesley P; Shack, R Bruce

    2018-01-01

    Ring avulsion injuries can range from soft tissue injury to complete amputation. Grading systems have been developed to guide treatment, but there is controversy with high-grade injuries. Traditionally, advanced ring injuries have been treated with completion amputation, but there is evidence that severe ring injuries can be salvaged. The purpose of this systematic review was to pool the current published data on ring injuries. A systematic review of the English literature published from 1980 to 2015 in PubMed and MEDLINE databases was conducted to identify patients who underwent treatment for ring avulsion injuries. Twenty studies of ring avulsion injuries met the inclusion criteria. There were a total of 572 patients reported with ring avulsion injuries. The Urbaniak class breakdown was class I (54 patients), class II (204 patients), and class III (314 patients). The average total arc of motion (TAM) for patients with a class I injury was 201.25 (n = 40). The average 2-point discrimination was 5.6 (n = 10). The average TAM for patients with a class II injury undergoing microsurgical revascularization was 187.0 (n = 114), and the average 2-point discrimination was 8.3 (n = 40). The average TAM for patients with a class III injury undergoing microsurgical revascularization was 168.2 (n = 170), and the average 2-point discrimination was 10.5 (n = 97). Ring avulsion injuries are commonly classified with the Urbaniak class system. Outcomes are superior for class I and II injuries, and there are select class III injuries that can be treated with replantation. Shared decision making with patients is imperative to determine whether replantation is appropriate.

  5. Investigation of piston ring – cylinder liner dry wear using a block-on-ring test rig

    DEFF Research Database (Denmark)

    Bihlet, Uffe; Klit, Peder; Felter, Christian L.

    Characterization of the wear of piston rings and cylinder liner is an important aspect of large two stroke diesel engine design. Two major wear mechanisms exist; corrosive wear and mechanical wear. This paper deals with the most aggressive form of the latter, which is known as scuffing. Different...... that ceramic coating on the piston ring decreases the dry wear rate of both piston ring and liner, while the coefficient of friction is increased....

  6. Novel Fiber-Optic Ring Acoustic Emission Sensor.

    Science.gov (United States)

    Wei, Peng; Han, Xiaole; Xia, Dong; Liu, Taolin; Lang, Hao

    2018-01-13

    Acoustic emission technology has been applied to many fields for many years. However, the conventional piezoelectric acoustic emission sensors cannot be used in extreme environments, such as those with heavy electromagnetic interference, high pressure, or strong corrosion. In this paper, a novel fiber-optic ring acoustic emission sensor is proposed. The sensor exhibits high sensitivity, anti-electromagnetic interference, and corrosion resistance. First, the principle of a novel fiber-optic ring sensor is introduced. Different from piezoelectric and other fiber acoustic emission sensors, this novel sensor includes both a sensing skeleton and a sensing fiber. Second, a heterodyne interferometric demodulating method is presented. In addition, a fiber-optic ring sensor acoustic emission system is built based on this method. Finally, fiber-optic ring acoustic emission experiments are performed. The novel fiber-optic ring sensor is glued onto the surface of an aluminum plate. The 150 kHz standard continuous sinusoidal signals and broken lead signals are successfully detected by the novel fiber-optic ring acoustic emission sensor. In addition, comparison to the piezoelectric acoustic emission sensor is performed, which shows the availability and reliability of the novel fiber-optic ring acoustic emission sensor. In the future, this novel fiber-optic ring acoustic emission sensor will provide a new route to acoustic emission detection in harsh environments.

  7. Nilradicals of skew Hurwitz series of rings

    Directory of Open Access Journals (Sweden)

    Morteza Ahmadi

    2015-05-01

    Full Text Available ‎For a ring endomorphism α of a ring R, ‎Krempa called α a rigid endomorphism if aα(a=0 implies a = 0 for a in R. ‎A ring R is called rigid if there exists a rigid endomorphism of R. ‎In this paper‎, ‎we extend the α-rigid property of a ring R to the upper nilradical N_r(R of R. ‎For an endomorphism α and the upper nilradical N_r(R of a ring R, ‎we introduce the condition (*: ‎N_r(R is a α-ideal of R and aα(a in N_r(R implies a in N_r(R for a in R. ‎We study characterizations of a ring R with an endomorphism α satisfying the condition (*, ‎and we investigate their related properties‎. ‎The connections between the upper nilradical of R and the upper nilradical of the skew Hurwitz series ring (HR,α of R are also investigated‎.

  8. Spin transitions in semiconductor quantum rings

    International Nuclear Information System (INIS)

    Baxevanis, Benjamin; Pfannkuche, Daniela

    2010-01-01

    We adopt the path integral Monte Carlo method to accurately resolve the total spin of the ground state of electrons confined in a quantum ring with different geometries. Using this method, an evaluation of the ground state of three electrons in a ring shows a spin transition to the fully polarized state by increasing the radius and thereby enhancing the Coulomb interaction. The total spin of the ground state is determined by the mutual interplay of confinement and electron-electron interaction. An analysis of the four-electron ring demonstrates that in this case no spin transitions take place. Furthermore, the effect of geometric distortion of the ring on its ground state has been investigated. Elliptically deforming the ring breaks the symmetry of the system and leads to the removal of orbital degeneracy. For strong distortion the splitting between hybridized states is sufficient to overcome the exchange-energy saving associated with a higher spin state. We have found that this effect removes the polarization of three electrons. Even in a four-electron ring the ground state is forced by the distortion to be unpolarized and thus suppressing the Hund's rule ground state.

  9. INJECTION EFFICIENCY IN COMPTON RING NESTOR

    Directory of Open Access Journals (Sweden)

    P. I. Gladkikh

    2017-12-01

    Full Text Available NESTOR is the hard X-ray source that is under commissioning at NSC KIPT. NESTOR based on the Compton scattering of laser photons on relativistic electrons. The structure of the facility can be represented as the following components: a linear accelerator, a transport channel, a storage ring, and a laser-optical system. Electrons are stored in the storage ring for energy of 40-200 MeV. Inevitable alignment errors of magnetic elements are strongly effect on the beam dynamics in the storage ring. These errors lead to a shift of the equilibrium orbit relative to the ideal one. Significant shift of the equilibrium orbit could lead to loss of the beam on physical apertures. Transverse sizes of electron and laser beams are only few tens of microns at the interaction point. The shift of electron beam at the interaction point could greatly complicate the operation adjustment of storage ring without sufficient beam position diagnostic system. This article presents the simulation results of the efficiency of electron beam accumulation in the NESTOR storage ring. Also, this article is devoted to electron beam dynamics due to alignment errors of magnetic element in the ring.

  10. Control of ring lasers by means of coupled cavities

    DEFF Research Database (Denmark)

    Buchhave, Preben; Abitan, Haim; Tidemand-Lichtenberg, Peter

    2000-01-01

    Variable phase coupling to an external ring is used to control a unidirectional ring laser. The observed behavior of the coupled rings is explained theoretically. We have found experimentally that by quickly changing the phase of the feedback from the external ring it is possible to Q......-switch the ring laser. Also, at certain values of the phase of the feedback in the external ring, instabilities in the total system occur and oscillations arise in the ring laser....

  11. Moving-ring field-reversed mirror reactor

    International Nuclear Information System (INIS)

    Smith, A.C. Jr.; Ashworth, C.P.; Abreu, K.E.

    1981-01-01

    We describe a first prototype fusion reactor design of the Moving-Ring Field-Reversed Mirror Reactor. The fusion fuel is confined in current-carrying rings of magnetically-field-reversed plasma. The plamsa rings, formed by a coaxial plasma gun, are magnetically compressed to ignition temperature while they are being injected into the reactor's burner section. DT ice pellets refuel the rings during the burn at a rate which maintains constant fusion power. A steady train of plasma rings moves at constant speed through the reactor under the influence of a slightly diverging magnetic field. The aluminum first wall and breeding zone structure minimize induced radioactivity; hands-on maintenance is possible on reactor components outside the breeding blanket. Helium removes the heat from the Li 2 O tritium breeding blanket and is used to generate steam. The reactor produces a constant, net power of 376 MW

  12. Artificial light harvesting by dimerized Möbius ring

    Science.gov (United States)

    Xu, Lei; Gong, Z. R.; Tao, Ming-Jie; Ai, Qing

    2018-04-01

    We theoretically study artificial light harvesting by a Möbius ring. When the donors in the ring are dimerized, the energies of the donor ring are split into two subbands. Because of the nontrivial Möbius boundary condition, both the photon and acceptor are coupled to all collective-excitation modes in the donor ring. Therefore, the quantum dynamics in the light harvesting is subtly influenced by dimerization in the Möbius ring. It is discovered that energy transfer is more efficient in a dimerized ring than that in an equally spaced ring. This discovery is also confirmed by a calculation with the perturbation theory, which is equivalent to the Wigner-Weisskopf approximation. Our findings may be beneficial to the optimal design of artificial light harvesting.

  13. ring system

    African Journals Online (AJOL)

    1,3,2-DIAZABORACYCLOALKANE. RING SYSTEM. Negussie Retta" and Robert H. Neilson. 'Department of Chemistry, Addis Ababa University, P.O. Box 1176, Addis Ababa, Ethiopia. Department of Chemistry, Texas Christian University.

  14. Ring cavity for a Raman capillary waveguide amplifier

    Science.gov (United States)

    Kurnit, N.A.

    1981-01-27

    A regenerative ring amplifier and regenerative ring oscillator are described which function to feed back a portion of the Stokes signal to complete the ring cavity. The ring cavity configuration allows the CO/sub 2/ laser pump signal and Stokes signal to copropagate through the Raman capillary waveguide amplifier. A Raman capillary waveguide amplifier is also provided in the return leg of the ring cavity to increase gain without increasing the round trip time. Additionally, the ring cavity can be designed such that the amplified Stokes signal is synchronous with the mode-locked spikes of the incoming CO/sub 2/ laser pump signal.

  15. Ring cavity for a Raman capillary waveguide amplifir

    Science.gov (United States)

    Kurnit, N.A.

    1981-01-27

    A regenerative ring amplifier and regenerative ring oscillator are described which function to feed back a portion of the Stokes signal to complete the ring cavity. The ring cavity configuration allows the CO/sub 2/ laser pump signal and Stokes signal to copropagate through the Raman capillary waveguide amplifier. A Raman capillary waveguide amplifier is also provided in the return leg of the ring cavity to increase gain without increasing the round trip time. Additionally, the ring cavity can be designed such that the amplified Stokes signal is synchronous with the mode-locked spikes of the incoming CO/sub 2/ laser pump signal.

  16. Experimental Study of Shock Generated Compressible Vortex Ring

    Science.gov (United States)

    Das, Debopam; Arakeri, Jaywant H.; Krothapalli, Anjaneyulu

    2000-11-01

    Formation of a compressible vortex ring and generation of sound associated with it is studied experimentally. Impulse of a shock wave is used to generate a vortex ring from the open end of a shock-tube. Vortex ring formation process has been studied in details using particle image Velocimetry (PIV). As the shock wave exits the tube it diffracts and expands. A circular vortex sheet forms at the edge and rolls up into a vortex ring. Far field microphone measurement shows that the acoustic pressure consists of a spike due to shock wave followed by a low frequency pressure wave of decaying nature, superimposed with high frequency pressure wave. Acoustic waves consist of waves due to expansion, waves formed in the tube during diaphragm breakage and waves associated with the vortex ring and shear-layer vortices. Unsteady evolution of the vortex ring and shear-layer vortices in the jet behind the ring is studied by measuring the velocity field using PIV. Corresponding vorticity field, circulation around the vortex core and growth rate of the vortex core is calculated from the measured velocity field. The velocity field in a compressible vortex ring differs from that of an incompressible ring due to the contribution from both shock and vortex ring.

  17. [Liesegang's rings resembling helminthiasis].

    Science.gov (United States)

    Zámecník, M; Riedl, I

    1996-12-01

    So called Liesegang's rings are lamellar corpuscles which develop after periodical precipitation of oversaturated solutions in gel medium. They can occur in cysts, closed cavities, inflammatory exudates and necroses. They resemble parasitic eggs, larvae or adult forms. A case of 28-year-old woman is presented with many Liesegang's rings in a stuff from dilated renal calyx. Their preliminary evaluation considered helminths, especially Dioctophyma renale.

  18. Synlig læring

    DEFF Research Database (Denmark)

    Brandsen, Mads

    2017-01-01

    Introduktionen af John Hatties synlig læring i den danske skoleverden møder stadig meget kritik. Mange lærere og pædagoger oplever synlig læring som en tornado, der vil opsuge og ødelægge deres særlige danske udgave af den kontinentale dannelsestænkning, didaktik og pædagogik. Spørgsmålet er om...

  19. How Jupiter's Ring Was Discovered.

    Science.gov (United States)

    Elliot, James; Kerr, Richard

    1985-01-01

    "Rings" (by astronomer James Elliot and science writer Richard Kerr) is a nontechnical book about the discovery and exploration of ring systems from the time of Galileo to the era of the Voyager spacecraft. One of this book's chapters is presented. (JN)

  20. Thioacetamide-induced cirrhosis in selenium-adequate mice displays rapid and persistent abnormity of hepatic selenoenzymes which are mute to selenium supplementation

    International Nuclear Information System (INIS)

    Zhang Jinsong; Wang Huali; Yu Hanqing

    2007-01-01

    Selenium reduction in cirrhosis is frequently reported. The known beneficial effect of selenium supplementation on cirrhosis is probably obtained from nutritionally selenium-deficient subjects. Whether selenium supplementation truly improves cirrhosis in general needs additional experimental investigation. Thioacetamide was used to induce cirrhosis in selenium-adequate and -deficient mice. Selenoenzyme activity and selenium content were measured and the influence of selenium supplementation was evaluated. In Se-adequate mice, thioacetamide-mediated rapid onset of hepatic oxidative stress resulted in an increase in thioredoxin reductase activity and a decrease in both glutathione peroxidase activity and selenium content. The inverse activity of selenoenzymes (i.e. TrxR activity goes up and GPx activity goes down) was persistent and mute to selenium supplementation during the progress of cirrhosis; accordingly, cirrhosis was not improved by selenium supplementation in any period. On the other hand, selenium supplementation to selenium-deficient mice always more efficiently increased hepatic glutathione peroxidase activity and selenium content compared with those treated with thioacetamide, indicating that thioacetamide impairs the liver bioavailability of selenium. Although thioacetamide profoundly affects hepatic selenium status in selenium-adequate mice, selenium supplementation does not modify the changes. Selenium supplementation to cirrhotic subjects with a background of nutritional selenium deficiency can improve selenium status but cannot restore hepatic glutathione peroxidase and selenium to normal levels