2,023 research outputs found
Deathly Drool: Evolutionary and Ecological Basis of Septic Bacteria in Komodo Dragon Mouths
No full textJ. J. Bull is with UT Austin; Marvin Whiteley is with UT Austin; Tim S. Jessop is with University of Melbourne.Komodo dragons, the world's largest lizard, dispatch their large ungulate prey by biting and tearing flesh. If a prey escapes, oral bacteria inoculated into the wound reputedly induce a sepsis that augments later prey capture by the same or other lizards. However, the ecological and evolutionary basis of sepsis in Komodo prey acquisition is controversial. Two models have been proposed. The “bacteria as venom” model postulates that the oral flora directly benefits the lizard in prey capture irrespective of any benefit to the bacteria. The “passive acquisition” model is that the oral flora of lizards reflects the bacteria found in carrion and sick prey, with no relevance to the ability to induce sepsis in subsequent prey. A third model is proposed and analyzed here, the “lizard-lizard epidemic” model. In this model, bacteria are spread indirectly from one lizard mouth to another. Prey escaping an initial attack act as vectors in infecting new lizards. This model requires specific life history characteristics and ways to refute the model based on these characteristics are proposed and tested. Dragon life histories (some details of which are reported here) prove remarkably consistent with the model, especially that multiple, unrelated lizards feed communally on large carcasses and that escaping, wounded prey are ultimately fed on by other lizards. The identities and evolutionary histories of bacteria in the oral flora may yield the most useful additional insights for further testing the epidemic model and can now be obtained with new technologies.Supported by National Institutes of Health (NIH) GM57756 and the University of Texas Miescher Regents Professorship to JJB and NIH AI075068 to MW. TSJ was supported by a Conservation Research Fellowship from the Zoological Society of San Diego. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Biological Sciences, School o
3D development of detachment faulting during continental breakup
No full textThe developing asymmetry of rifting and continental breakup to form rifted margins has been much debated, as has the formation, mechanics and role of extensional detachments. Bespoke 3D seismic reflection data across the Galicia margin, west of Spain, image in unprecedented detail an asymmetric detachment (the S reflector). Mapping S in 3D reveals its surface is corrugated, proving that the overlying crustal blocks slipped on S surface during the rifting. Crucially, the 3D data show that the corrugations on S perfectly match the corrugations observed on the present-day block-bounding faults, demonstrating that S is a composite surface, comprising the juxtaposed rotated roots of block-bounding faults as in a rolling hinge system with each new fault propagation moving rifting oceanward; changes in the orientation of the corrugations record the same oceanward migration. However, in contrast to previous rolling hinge models, the slip of the crustal blocks on S occurred at angles as low as ∼20°, requiring that S was unusually weak, consistent with the hydration of the underlying mantle by seawater ingress following the embrittlement of the entire crust. As the crust only becomes entirely brittle once thinned to ∼10 km, the asymmetric S detachment and the hyper-extension of the continental crust only developed late in the rifting process, which is consistent with the observed development of asymmetry between conjugate magma poor margin pairs. The 3D volume allows analysis of the heaves and along strike architecture of the normal faults, whose planes laterally die or spatially link together, implying overlaps in faults activity during hyper-extension. Our results thus reveal for the first time the 3D mechanics and timing of detachment faulting growth, the relationship between the detachment and the network of block-bounding faults above it and the key processes controlling the asymmetrical development of conjugate rifted margins
Algebras with transitive automorphism groups
No full textPT: J; CR: GOLOMB SW, 1969, COMBINATORIAL MATH I GROSS F, 1972, P AM MATH SOC, V31, P10 IVANOV DN, 1982, VESTNIK MOSKOV U MAT, V37, P69 KOSTRIKIN AI, 1965, IZVESTIYA AKAD NAUK, V29, P471 SHULT EE, 1969, ILLINOIS J MATH, V13, P625 SIMMONS GJ, 1970, AM MATH MONTHLY, V77, P743 SWEET L, 1975, CANAD MATH B, V17, P723 SWEET LG, 1975, P AM MATH SOC, V48, P321; NR: 8; TC: 1; J9: CAN MATH BULL-BULL CAN MATH; PG: 3; GA: C9332Source type: Electronic(1
Surficial and bedrock engineering geology, landslide inventory and susceptibility, and surface hydrography of the Bull Run Watershed, Clackamas and Multnomah counties, Oregon
No full textThis archived document is maintained by the Oregon State Library as part of the Oregon Documents Depository Program. It is for informational purposes and may not be suitable for legal purposes.Title from disc label.CD-ROM includes PDF version of report in high and low resolutions, GIS folder with three ESRI geodatabases (Bull Run Landslide Inventory, Bull Run Shallow Deep Landslide Susceptibility, Bull Run Hydrography), Appendices folder (containing Supplementary Material for Creating Landslide Inventory Data, Supplementary Material for Creating shallow landslide susceptibility Data, Supplementary material for Creating Deep landslide susceptibility Data, and Process Used to Create the Surface Hydrography Geodatabase), Map plates folder containing 5 plates (Landslide inventory map of the Bull Run Watershed, Shallow landslide susceptibility map of the Bull Run Watershed, Deep landslide susceptibility map of the Bull Run Watershed, Detailed map of the Bull Run Lake Landslide, Surface hydrography map of the Bull Run Watershed).Includes bibliographical references.This study was funded in part by the City of Portland Water Bureau (intergovernmental agreement IGA #12122012)Mode of access: Internet from the Oregon Government Publications Collection.Text in English
Body mass index cut offs to define thinness in children and adolescents: international survey
No full textOBJECTIVE: To determine cut offs to define thinness in children and adolescents, based on body mass index at age 18 years.DESIGN: International survey of six large nationally representative cross sectional studies on growth. SETTING: Brazil, Great Britain, Hong Kong, the Netherlands, Singapore, and the United States. SUBJECTS: 97 876 males and 94 851 females from birth to 25 years. MAIN OUTCOME MEASURE: Body mass index (BMI, weight/height(2)). RESULTS: The World Health Organization defines grade 2 thinness in adults as BMI <17. This same cut off, applied to the six datasets at age 18 years, gave mean BMI close to a z score of -2 and 80% of the median. Thus it matches existing criteria for wasting in children based on weight for height. For each dataset, centile curves were drawn to pass through the cut off of BMI 17 at 18 years. The resulting curves were averaged to provide age and sex specific cut-off points from 2-18 years. Similar cut offs were derived based on BMI 16 and 18.5 at 18 years, together providing definitions of thinness grades 1, 2, and 3 in children and adolescents consistent with the WHO adult definitions. CONCLUSIONS: The proposed cut-off points should help to provide internationally comparable prevalence rates of thinness in children and adolescent
A low-angle detachment fault revealed: three-dimensional images of the S-reflector fault zone along the Galicia passive margin
No full textA new 3-D seismic reflection volume over the Galicia margin continent–ocean transition zone provides an unprecedented view of the prominent S-reflector detachment fault that underlies the outer part of the margin. This volume images the fault's structure from breakaway to termination. The filtered time-structure map of the S-reflector shows coherent corrugations parallel to the expected paleo-extension directions with an average azimuth of 107°. These corrugations maintain their orientations, wavelengths and amplitudes where overlying faults sole into the S-reflector, suggesting that the parts of the detachment fault containing multiple crustal blocks may have slipped as discrete units during its late stages. Another interface above the S-reflector, here named S′, is identified and interpreted as the upper boundary of the fault zone associated with the detachment fault. This layer, named the S-interval, thickens by tens of meters from SE to NW in the direction of transport. Localized thick accumulations also occur near overlying fault intersections, suggesting either non-uniform fault rock production, or redistribution of fault rock during slip. These observations have important implications for understanding how detachment faults form and evolve over time. 3-D seismic reflection imaging has enabled unique insights into fault slip history, fault rock production and redistribution
Relationship between domoic acid levels in the blue mussel (Mytilus-edulis) and toxicity in mice
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Property A and affine buildings
No full textYu's Property A is a non-equivariant generalisation of amenability introduced in his study of the coarse Baum Connes conjecture. In this paper we show that all affine buildings of type A2, B2 and G2 have Property A. Together with results of Guentner, Higson and Weinberger, this completes a programme to show that all affine building have Property A. In passing we use our technique to obtain a new proof for groups acting on buildings.The author was supported by EPSRC postdoctoral fellowship EP/C53171X/1.<br/
New intercalation compounds of conjugated polymers. Encapsulation of polyaniline in MoS2.
No full textPT: J; CR: BEIN T, 1989, ANGEW CHEM INT EDIT, V28, P1692 BISSESSUR R, UNPUB COX SD, 1991, J PHYS CHEM-US, V95, P710 DAY P, 1982, MOL CRYST LIQ CRYST, V86, P163 DIVIGALPITIYA WMR, 1989, SCIENCE, V246, P369 DIVIGALPITIYA WMR, 1991, APPL SURF SCI, V48, P572 ENZEL P, 1989, J CHEM SOC CHEM COMM, P1326 ENZEL P, 1989, J PHYS CHEM-US, V93, P6270 ENZEL P, 1992, CHEM MATER, V4, P819 GEE MA, 1986, MATER RES BULL, V21, P543 JOENSEN P, 1986, MATER RES BULL, V21, P457 KANATZIDIS MG, 1987, J AM CHEM SOC, V109, P3797 KANATZIDIS MG, 1989, J AM CHEM SOC, V111, P4139 KANATZIDIS MG, 1990, ADV MATER, V2, P364 KANATZIDIS MG, 1990, CHEM MATER, V2, P222 MEHROTRA V, 1991, SOLID STATE COMMUN, V77, P155 MEHROTRA V, 1992, SOLID STATE IONICS, V51, P115 MURPHY DW, 1979, SCIENCE, V205, P651 NAZAR LF, 1992, J AM CHEM SOC, V114, P6239 PEREIRA C, 1991, J PHYS CHEM-US, V95, P705 PILLION JE, 1991, CHEM MATER, V3, P777 PY MA, 1983, CAN J PHYS, V61, P76 SCHOLLHORN R, 1974, J LESS-COMMON MET, V36, P229 SOMA Y, 1983, CHEM PHYS LETT, V99, P153 SOMOANO RB, 1973, J CHEM PHYS, V58, P697 SOMOANO RB, 1975, J PHYS CHEM-US, V62, P1068 TIEKE B, 1983, MOL CRYST LIQ CRYST, V93, P119 WHITTINGHAM MS, 1976, J ELECTROCHEM SOC, V123, P315 WHITTINGHAM MS, 1978, PROG SOLID STATE CH, V12, P41 WU CG, 1989, POLYM MATER SCI ENG, V61, P969 WYPYCH F, 1992, J CHEM SOC CHEM COMM, V19, P136 YANG D, 1991, PHYS REV B, V43, P12053; NR: 32; TC: 113; J9: CHEM MATER; PG: 2; GA: LC738Source type: Electronic(1
Leveraging omics for bull trout conservation
No full textDeclines in bull trout (Salvelinus confluentus) populations across North America have prompted increased collaboration among academic, governmental, private, non-profit, and Indigenous groups to improve conservation strategies. Bull trout experience multiple stressors including habitat fragmentation, interspecific competition, fishing mortality, and climate change-induced warming. These threats to bull trout populations highlight the need to utilize approaches to rapidly assess the health and status of wild populations. This review synthesizes recent advances in omic tools applied to bull trout conservation with an emphasis on transcriptional profiling, genomics, and environmental DNA. Given their protected status, which limits lethal sampling in the wild, non-lethal and minimally invasive sample collection is required. Integrating omics with existing frameworks such as species distribution modelling has the potential to modernize conservation practices and guide recovery strategies for this at-risk species. Addressing limitations of current omic approaches for bull trout, including the absence of a sequenced genome, will be important to further advance tools for their management.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
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