Sample records for cayman rise mcr
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Diverse styles of submarine venting on the ultraslow spreading Mid-Cayman Rise
German, C. R.; Bowen, A.; Coleman, M. L.; Honig, D. L.; Huber, J. A.; Jakuba, M. V.; Kinsey, J. C.; Kurz, M. D.; Leroy, S.; McDermott, J. M.; de Lépinay, B. Mercier; Nakamura, K.; Seewald, J. S.; Smith, J. L.; Sylva, S. P.; Van Dover, C. L.; Whitcomb, L. L.; Yoerger, D. R.
2010-01-01
Thirty years after the first discovery of high-temperature submarine venting, the vast majority of the global mid-ocean ridge remains unexplored for hydrothermal activity. Of particular interest are the world’s ultraslow spreading ridges that were the last to be demonstrated to host high-temperature venting but may host systems particularly relevant to prebiotic chemistry and the origins of life. Here we report evidence for previously unknown, diverse, and very deep hydrothermal vents along the ∼110 km long, ultraslow spreading Mid-Cayman Rise (MCR). Our data indicate that the MCR hosts at least three discrete hydrothermal sites, each representing a different type of water-rock interaction, including both mafic and ultramafic systems and, at ∼5,000 m, the deepest known hydrothermal vent. Although submarine hydrothermal circulation, in which seawater percolates through and reacts with host lithologies, occurs on all mid-ocean ridges, the diversity of vent types identified here and their relative geographic isolation make the MCR unique in the oceans. These new sites offer prospects for an expanded range of vent-fluid compositions, varieties of abiotic organic chemical synthesis and extremophile microorganisms, and unparalleled faunal biodiversity—all in close proximity. PMID:20660317
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Diverse styles of submarine venting on the ultra-slow spreading Mid-Cayman Rise (Invited)
NASA Astrophysics Data System (ADS)
German, C. R.; Bowen, A.; Coleman, M. L.; Honig, D. L.; Huber, J. A.; Jakuba, M.; Kinsey, J. C.; Kurz, M. D.; Leroy, S.; McDermott, J.; Mercier de Lepinay, B. F.; Nakamura, K.; Seewald, J.; Smith, J.; Sylva, S.; van Dover, C. L.; Whitcomb, L. L.; Yoerger, D. R.
2010-12-01
Thirty years after the first discovery of high-temperature submarine venting, the vast majority of the global Mid Ocean Ridge remains unexplored for hydrothermal activity. Of particular interest are the world’s ultra-slow spreading ridges which were the last to be demonstrated to host high-temperature venting, but may host systems particularly relevant to pre-biotic chemistry and the origins of life. Here we report first evidence for diverse and very deep hydrothermal vents along the ~110 km long, ultra-slow spreading Mid-Cayman Rise collected using a combination of CTD-rosette operations and dives of the Hybrid Remotely Operated Vehicle (HROV) Nereus in 2009 followed by shore based work-up of samples for geochemical and microbiological analyses. Our data indicate that the Mid-Cayman Rise hosts at least three discrete hydrothermal sites, each representing a different type of water-rock interaction, including both mafic and ultra-mafic systems and, at ~5000 m, the deepest known hydrothermal vent. Although submarine hydrothermal circulation, in which seawater percolates through and reacts with host lithologies, occurs on all mid-ocean ridges, the diversity of vent-types identified here and their relative geographic isolation make the Mid-Cayman Rise unique in the oceans. These new sites offer prospects for: an expanded range of vent-fluid compositions; varieties of abiotic organic chemical synthesis and extremophile microorganisms; and unparalleled faunal biodiversity - all in close proximity.
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NASA Astrophysics Data System (ADS)
Marr, C.; John, B. E.; Cheadle, M. J.; German, C. R.
2014-12-01
Two well-preserved core complexes at the Mid-Cayman Rise (MCR), Mt Dent and Mt Hudson, provide an opportunity to examine the deformation history and rheology of detachment faults at an ultra-slow spreading ridge. Samples from the CAYTROUGH (1976-77) project and the Nautilus NA034 cruise (2013) were selected for detailed petrographic and microstructural study. Surface samples from Mt. Dent (near the center of the MCR) provide insight into lateral variation in footwall rock type and deformation history across a core complex in both the across and down dip directions. In contrast, sampling of Mt. Hudson (SE corner of the MCR) focuses on a high-angle, crosscutting normal fault scarp, which provides a cross section of the detachment fault system. Sampling across Mt Dent reveals that the footwall is composed of heterogeneously-distributed gabbro (47%) and peridotite (20%) with basaltic cover (33%) dominating the top of the core complex. Sampling of Mt Hudson is restricted to the normal fault scarp cutting the core complex and suggests the interior is dominated by gabbro (85% gabbro, 11% peridotite, 4% basalt). At Mt. Dent, peridotite is exposed within ~4km of the breakaway indicating that the Mt. Dent detachment does not cut Penrose-style oceanic crust. The sample set provides evidence of a full down-temperature sequence of detachment related-fault rocks, from possible granulite and clear amphibolite mylonitizatization to prehnite-pumpellyite brittle deformation. Both detachments show low-temperature brittle deformation overprinting higher temperature plastic fabrics. Fe-Ti oxide gabbro mylonites dominate the sample set, and plastic deformation of plagioclase is recorded in samples collected as near as ~4km from the inferred breakaway along the southern flank of Mt. Dent, suggesting the brittle-plastic transition was initially at ~3km depth. Recovered samples suggest strain associated with both detachment systems is localized into discrete mylonitic shear zones (~1-10cm
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The Delineation of Coral Bleaching Thresholds and Future Reef Health, Little Cayman Cayman Islands
NASA Astrophysics Data System (ADS)
Manfrino, C.; Van Hooidonk, R. J.; Manzello, D.; Hendee, J.
2011-12-01
The global rise in sea temperature through anthropogenic climate change is affecting coral reef ecosystems through a phenomenon known as coral bleaching; a common reaction to thermally induced physiological stress in reef-building corals that often leads to coral mortality. We describe aspects of the most prevalent episode of coral bleaching ever recorded at Little Cayman, Cayman Islands, during the fall of 2009. Scleractinian coral species exhibiting susceptibility to thermal stress and bleaching in Little Cayman were, in order, Siderastrea siderea, Montastraea annularis, and Montastraea faveolata, while Diplora strigosa and Agaricia spp. were less so, yet still showed considerable bleaching prevalence and severity. In contrast, the least susceptible were Porites porites, Porites astreoides, and Montastraea cavernosa. These observations and other reported observations of coral bleaching, together with 29 years (1982 - 2010) of satellite-derived sea surface temperatures, were used in a Degree Heating Weeks (DHW) and Peirce Skill Score (PSS) analysis to calculate a bleaching threshold above which bleaching was expected to occur. A threshold of 4.2 DHW had the highest skill, with a PSS of 0.70. This threshold and susceptibility ranking are used in combination with SST data from global, coupled ocean-atmosphere general circulation models (GCM) from the fourth IPCC assessment to forecast future reef health on Little Cayman. While these GCMs possess skill in reproducing many aspects of climate, they vary in their ability to correctly capture such parameters as the tropical ocean seasonal cycle and El Niño Southern Oscillation (ENSO) variability. These model weaknesses likely reduce the skill of coral bleaching predictions. To overcome this, a multi-model ensemble of GCMs are corrected for their mean, annual cycle and ENSO variability prior to calculating future thermal stress. Preliminary results show that from 2045 on Little Cayman is likely to see more than two
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Petrology of gabbroic rocks from the Mid-Cayman rise spreading center
NASA Technical Reports Server (NTRS)
Elthon, Don
1987-01-01
Mineral analyses of oxide and silicate phases from a suite (collected with the DSRV Alvin in January 1976 and July 1977) of 48 gabbroic rocks collected from the vicinity of the Mid-Cayman Rise spreading center are reported. Mineral compositions of these anorthosites, leuco-troctolite, leuco-olivine gabbros, olivine gabbros, leuco-gabbros, and gabbros indicate the cumulate rocks have been produced by the crystal fractionation of basaltic liquids. Certain features of these rocks are inconsistent with the occurrence of this fractionation at low pressures (1 atm to 2 kbar). Although the experimental data are not available to conclusively demonstrate that the effects seen were produced at moderate pressures (5-10 kbar), the effects are similar to those predicted thermodynamically and to those observed in limited experimental studies within this pressure range. It is therefore suggested that the most likely scenario for the production of these gabbroic rocks is the moderate-pressure crystallization of basaltic magmas within deep-seated magma chambers underneath this slow-spreading center.
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Coral bleaching at Little Cayman, Cayman Islands 2009
NASA Astrophysics Data System (ADS)
van Hooidonk, Ruben J.; Manzello, Derek P.; Moye, Jessica; Brandt, Marilyn E.; Hendee, James C.; McCoy, Croy; Manfrino, Carrie
2012-06-01
The global rise in sea temperature through anthropogenic climate change is affecting coral reef ecosystems through a phenomenon known as coral bleaching; that is, the whitening of corals due to the loss of the symbiotic zooxanthellae which impart corals with their characteristic vivid coloration. We describe aspects of the most prevalent episode of coral bleaching ever recorded at Little Cayman, Cayman Islands, during the fall of 2009. The most susceptible corals were found to be, in order, Siderastrea siderea, Montastraea annularis, and Montastraea faveolata, while Diplora strigosa and Agaricia spp. were less so, yet still showed considerable bleaching prevalence and severity. Those found to be least susceptible were Porites porites, Porites astreoides, and Montastraea cavernosa. These observations and other reported observations of coral bleaching, together with 29 years (1982-2010) of satellite-derived sea surface temperatures, were used to optimize bleaching predictions at this location. To do this a Degree Heating Weeks (DHW) and Peirce Skill Score (PSS) analysis was employed to calculate a local bleaching threshold above which bleaching was expected to occur. A threshold of 4.2 DHW had the highest skill, with a PSS of 0.70. The method outlined here could be applied to other regions to find the optimal bleaching threshold and improve bleaching predictions.
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Extreme Tolerance to Elevated Pressure in a Thermococcus isolate from the Mid-Cayman Rise
NASA Astrophysics Data System (ADS)
Narasingarao, P.; Huber, J. A.; Schrenk, M. O.; Bartlett, D.
2013-12-01
Hydrothermal systems are windows into the deep biosphere. Venting fluids with temperatures up to 400°C containing gases such as H2, CO2, H2S and CH4 provide an oasis of life in the deep ocean primarily based on chemosynthesis. The Mid-Cayman Rise (MCR) includes the deepest hydrothermal vent system known thus far, and is characterized by two venting sites Piccard (4950m) and Von Damm (2350m). Here we demonstrate the remarkable high pressure tolerance limits of a Thermococcus sp. designated strain 175, isolated from samples collected from Piccard during an expedition in 2012. Diffuse venting fluids collected at the site resulted in the isolation of several Thermococcus strains capable of growth in basal salts medium supplemented with H2/CO2 and yeast extract, along with sulfur as an electron acceptor. Given the importance of pressure as an environmental parameter influencing evolution and adaptation of deep-sea life, the pressure tolerance of Thermococcus strain 175 was tested. High pressure incubations were originally conducted in serum vials filled completely with growth medium and therefore lacking all headspace gas. To test for growth with H2/CO2 , modified hungate tubes with a piston mechanism were used (Bowles et al. 2011) . The results indicate that strain 175 can grow at 90°C up to 120 megapascal (MPa). Growth rates are comparable when the strain is grown at atmospheric pressure or at 120 MPa pressure. Morphologically, the strain is irregular cocci and does not show any changes in its cellular structure when switched between atmospheric pressure and elevated pressure. This wide range of pressure tolerance has not been previously observed in other microorganisms, including Pyrococcus yayanosii CH1 (Zeng et al., 2009) which is also capable of growth at 120MPa but does not grow below 15 MPa. Thermococcus strain 175 represents an excellent model system to study high pressure adaptation due to its high growth rate and broad range of growth pressures. The
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NASA Astrophysics Data System (ADS)
German, C. R.
2012-12-01
In January 2012 our multi-national and multi-disciplinary team conducted a series of 10 ROV Jason dives to conduct first detailed and systematic sampling of the Mid Cayman Rise hydrothermal systems at the Von Damm and Piccard hydrothermal fields. At Von Damm, hydrothermal venting is focused at and around a large conical structure that is approximately 120 m in diameter and rises at least 80m from the surrounding, largely sedimented seafloor. Clear fluids emitted from multiple sites around the flanks of the mound fall in the temperature range 110-130°C and fall on a common mixing line with hotter (>200°C) clear fluids emitted from an 8m tall spire at the summit which show clear evidence of ultramafic influence. Outcrop close to the vent-site is rare and the cone itself appear to consist of clay minerals derived from highly altered host rock. The dominant fauna at the summit of Von Damm are a new species of chemosynthetic shrimp but elsewhere the site also hosts two distinct species of chemosynthetic tube worm as well as at least one species of gastropod. The adjacent Piccard site, at ~5000m depth comprises 7 distinct sulfide mounds, 3 of which are currently active: Beebe Vents, Beebe Woods and Beebe Sea. Beebe Vents consists of 5 vigorous black smoker chimneys with maximum temperatures in the range 400-403°C while at Beebe Woods a more highly colonized thicket of up to 8m tall chimneys includes predominantly beehive diffusers with rare black smokers emitting fluids up to 353°C. Beebe Sea a diffuse site emitting fluids at 38°C Tmax, is the largest of the currently active mounds and immediately abuts a tall (8m) rift that strikes NE-SW bisecting the host Axial Volcanic Ridge. The fauna at Piccard are less diverse than at Von Damm and, predominantly, comprise the same species of MCR shrimp, a distinct gastropod species and abundant anemones.
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Discovery of hydrothermally active and extinct talc mounds on the Mid-Cayman Rise
NASA Astrophysics Data System (ADS)
Hodgkinson, M.; Murton, B. J.; Roberts, S.
2013-12-01
Since 1977, hydrothermal vents have been the subject of intense scientific interest due to their role in cooling the oceanic crust and global geochemical cycles. Until now, two types of hydrothermal system have been identified: one, driven by magmatic heat extruding ';black smoker' fluids; and another, involving serpentinisation of ultramafic rocks and the precipitation of carbonate/brucite chimneys. Here, we present details of a new, off-axis type of hydrothermal system consisting of mounds of predominately botryoidal talc (a magnesium-silicate) with accessory silica and copper sulphides, and chimneys exhaling fluids of moderate temperature and pH. Discovered on the Mid-Cayman Rise (MCR) in 2010, the Von Damm Vent Field (VDVF) features a NNW-ESE-trending line of four overlapping cones, the largest of which is 75 m high by 150 m in diameter. The VDVF is hosted in the gabbroic footwall of the Mount Dent Oceanic Core Complex (MDOCC), which includes serpentinised peridotite at depth. The largest cone vents clear fluids from two main orifices at its summit, with primary temperatures of 215°C. Elsewhere, both focussed and diffuse flow areas emit fluids with temperatures of up to 150°C. The surrounding ~1 m thick pelagic sediment contains abundant pockmarks that emit methane-rich fluids at temperatures of less than 10°C. During the return to the MCR in early 2013, several other talc mounds were discovered within a kilometre of the active VDVF. These inactive mounds also comprise an assemblage of botryoidal talc, silica, disseminated sulphides (including chalcopyrite) and sulphates. One of these mounds (Mystic Mount) is double the volume of the active VDVF. The unique dominance of talc as the major mineral forming the hydrothermal structures indicates unusual vent fluid compositions that are able to carry both copper (at high-temperatures) and precipitate magnesium silicate. Thermodynamic modelling indicates that talc precipitates on mixing a moderately acidic, silica
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NASA Astrophysics Data System (ADS)
Hoffert, M.; Anderson, R. E.; Stepanauskas, R.; Huber, J. A.
2017-12-01
Deep-sea hydrothermal vents sustain diverse communities of microorganisms. The effects of geochemical and biological interactions on the process of evolution in these ecosystems remains poorly understood because the majority of subsurface microorganisms remain uncultivated. By examining metagenomic samples from hydrothermal fluids and mapping the samples to closely-related genomes found in vent sites, we can better understand how the process of evolution is affected by the geochemical and environmental context in deep-sea vents. The Mid-Cayman Rise is a spreading ridge that hosts both mafic-influenced and ultramafic-influenced vent fields. Previous research on metagenomic samples from sites in the Mid-Cayman Rise has shown that these vents contain metabolically and taxonomically diverse microbial communities. Here, we investigate five single cell amplified Methanothermococcus genomes (SAGs) to investigate patterns in pangenomic variation and molecular evolution in these methanogens. Mappings of metagenomic reads from 15 sample sites to the SAGs reveal substantial variation in Methanothermococcus population abundance, nucleotide variability and selection pressure among the 15 geochemically distinct sample sites. Within each sample site, we observed distinct patterns of single nucleotide variant (SNV) accumulation and selection pressure within the SAG populations. Closely related genomes showed similar patterns of SNV accumulation. Analysis of open reading frames (ORFs) from the SAGs indicated that homologous genes accumulated variation at the same rate. For example, a genomic island for Nif genes was identified in three of the five genomes with significantly elevated SNV counts. dN/dS analyses revealed evidence for frequency-dependent selection, in which genes unique to individual SAGs displayed elevated diversifying selection relative to other genes. These results indicate that different strains of Methanothermococcus outcompete others in specific environmental
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NASA Astrophysics Data System (ADS)
Huber, J. A.; Reveillaud, J. C.; Stepanauskas, R.; McDermott, J. M.; Sylva, S. P.; Seewald, J.
2013-12-01
The Mid-Cayman Rise (MCR) is Earth's deepest and slowest spreading mid-ocean ridge located in the western Caribbean. With an axial rift valley floor at a depth of ~4200-6500 m, it represents one of the deepest sections of ridge crest worldwide. In 2009, the world's deepest hydrothermal vents (Piccard at 4960 m) and an ultramafic-influenced system only 20 km away on top of an oceanic core complex (Von Damm at 2350 m) were discovered along the MCR. Each site is hosted in a distinct geologic setting with different thermal and chemical regimes. The Von Damm site is a particularly interesting location to examine chemolithoautotrophic subseafloor microbial communities due to the abundant hydrogen, methane, and organic compounds in the venting fluids. Here, we used a combination of stable isotope tracing, next-generation sequencing, and single cell techniques to determine the identity, activity, and genomic repertoire of subseafloor anaerobic archaea involved in methane cycling in hydrothermal fluids venting at the Von Damm site. Molecular sequencing of phylogenetic marker genes revealed the presence of diverse archaea that both generate and consume methane across a geochemical and thermal spectrum of vents. Stable isotope tracing experiments were used to detect biological utilization of formate and dissolved inorganic carbon, and methane generation at 70 °C under anaerobic conditions. Results indicate that methanogenesis with formate as a substrate is occurring at 70 °C at two Von Damm sites, Ginger Castle and the Main Orifice. The results are consistent with thermodynamic predictions for carbon speciation at the temperatures encountered at the ultramafic-hosted Von Damm, where formate is predicted to be thermodynamically stable, and may thus serve as a an important source of carbon. Diverse thermophilic methanogenic archaea belonging to the genera Methanothermococcus were detected at all vent sites with both 16S rRNA tag sequencing and single cell sorting. Other
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NASA Astrophysics Data System (ADS)
Galambos, D.; Reveillaud, J. C.; Anderson, R.; Huber, J. A.
2017-12-01
Deep-sea hydrothermal vent systems host a wide diversity of bacteria, archaea and viruses. Although the geochemical conditions at these vents are well-documented, the relative metabolic activity of microbial lineages, especially among archaea, remains poorly characterized. The deep, slow-spreading Mid-Cayman Rise, which hosts the mafic-influenced Piccard and ultramafic-influenced Von Damm vent fields, allows for the comparison of vent sites with different geochemical characteristics. Previous metagenomic work indicated that despite the distinct geochemistry at Von Damm and Piccard, the functional profile of microbial communities between the two sites was similar. We examined relative metabolic gene activity using a metatranscriptomic analysis and observed functional similarity between Von Damm and Piccard, which is consistent with previous results. Notably, the relative expression of the methyl-coenzyme M reductase (mcr) gene was elevated in both vent fields. Additionally, we analyzed the ratio of RNA expression to DNA abundance of fifteen archaeal metagenome-assembled genomes (MAGs) across the two fields. Previous work showed higher archaeal diversity at Von Damm; our results indicate relatively even expression among archaeal lineages at Von Damm. In contrast, we observed lower archaeal diversity at Piccard, but individual archaeal lineages were very highly expressed; Thermoprotei showed elevated transcriptional activity, which is consistent with higher temperatures and sulfur levels at Piccard. At both Von Damm and Piccard, specific Methanococcus lineages were more highly expressed than others. Future analyses will more closely examine metabolic genes in these Methanococcus MAGs to determine why some lineages are more active at a vent field than others. We will conduct further statistical analyses to determine whether significant differences exist between Von Damm and Piccard and whether there are correlations between geochemical metadata and metabolic gene or
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Subseafloor Microbial Life in Venting Fluids from the Mid Cayman Rise Hydrothermal System
NASA Astrophysics Data System (ADS)
Huber, J. A.; Reveillaud, J.; Reddington, E.; McDermott, J. M.; Sylva, S. P.; Breier, J. A.; German, C. R.; Seewald, J.
2012-12-01
In hard rock seafloor environments, fluids emanating from hydrothermal vents are one of the best windows into the subseafloor and its resident microbial community. The functional consequences of an extensive population of microbes living in the subseafloor remains unknown, as does our understanding of how these organisms interact with one another and influence the biogeochemistry of the oceans. Here we report the abundance, activity, and diversity of microbes in venting fluids collected from two newly discovered deep-sea hydrothermal vents along the ultra-slow spreading Mid-Cayman Rise (MCR). Fluids for geochemical and microbial analysis were collected from the Von Damm and Piccard vent fields, which are located within 20 km of one another, yet have extremely different thermal, geological, and depth regimes. Geochemical data indicates that both fields are highly enriched in volatiles, in particular hydrogen and methane, important energy sources for and by-products of microbial metabolism. At both sites, total microbial cell counts in the fluids ranged in concentration from 5 x 10 4 to 3 x 10 5 cells ml-1 , with background seawater concentrations of 1-2 x 10 4 cells ml-1 . In addition, distinct cell morphologies and clusters of cells not visible in background seawater were seen, including large filaments and mineral particles colonized by microbial cells. These results indicate local enrichments of microbial communities in the venting fluids, distinct from background populations, and are consistent with previous enumerations of microbial cells in venting fluids. Stable isotope tracing experiments were used to detect utilization of acetate, formate, and dissolve inorganic carbon and generation of methane at 70 °C under anaerobic conditions. At Von Damm, a putatively ultra-mafic hosted site located at ~2200 m with a maximum temperature of 226 °C, stable isotope tracing experiments indicate methanogenesis is occurring in most fluid samples. No activity was detected
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Rebelo, Ana Rita; Bortolaia, Valeria; Kjeldgaard, Jette S; Pedersen, Susanne K; Leekitcharoenphon, Pimlapas; Hansen, Inge M; Guerra, Beatriz; Malorny, Burkhard; Borowiak, Maria; Hammerl, Jens Andre; Battisti, Antonio; Franco, Alessia; Alba, Patricia; Perrin-Guyomard, Agnes; Granier, Sophie A; De Frutos Escobar, Cristina; Malhotra-Kumar, Surbhi; Villa, Laura; Carattoli, Alessandra; Hendriksen, Rene S
2018-01-01
Background and aim Plasmid-mediated colistin resistance mechanisms have been identified worldwide in the past years. A multiplex polymerase chain reaction (PCR) protocol for detection of all currently known transferable colistin resistance genes (mcr-1 to mcr-5, and variants) in Enterobacteriaceae was developed for surveillance or research purposes. Methods: We designed four new primer pairs to amplify mcr-1, mcr-2, mcr-3 and mcr-4 gene products and used the originally described primers for mcr-5 to obtain a stepwise separation of ca 200 bp between amplicons. The primer pairs and amplification conditions allow for single or multiple detection of all currently described mcr genes and their variants present in Enterobacteriaceae. The protocol was validated testing 49 European Escherichia coli and Salmonella isolates of animal origin. Results: Multiplex PCR results in bovine and porcine isolates from Spain, Germany, France and Italy showed full concordance with whole genome sequence data. The method was able to detect mcr-1, mcr-3 and mcr-4 as singletons or in different combinations as they were present in the test isolates. One new mcr-4 variant, mcr-4.3, was also identified. Conclusions: This method allows rapid identification of mcr-positive bacteria and overcomes the challenges of phenotypic detection of colistin resistance. The multiplex PCR should be particularly interesting in settings or laboratories with limited resources for performing genetic analysis as it provides information on the mechanism of colistin resistance without requiring genome sequencing. PMID:29439754
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The nature of the crust under Cayman Trough from gravity
ten Brink, Uri S.; Coleman, D.F.; Dillon, William P.
2002-01-01
Considerable crustal thickness variations are inferred along Cayman Trough, a slow-spreading ocean basin in the Caribbean Sea, from modeling of the gravity field. The crust to a distance of 50 km from the spreading center is only 2–3 km thick in agreement with dredge and dive results. Crustal thickness increases to ∼5.5 km at distances between 100 and 430 km west of the spreading center and to 3.5–6 km at distances between 60 and 370 km east of the spreading center. The increase in thickness is interpreted to represent serpentinization of the uppermost mantle lithosphere, rather than a true increase in the volume of accreted ocean crust. Serpentinized peridotite rocks have indeed been dredged from the base of escarpments of oceanic crust rocks in Cayman Trough. Laboratory-measured density and P-wave speed of peridotite with 40–50% serpentine are similar to the observed speed in published refraction results and to the inferred density from the model. Crustal thickness gradually increases to 7–8 km at the far ends of the trough partially in areas where sea floor magnetic anomalies were identified. Basement depth becomes gradually shallower starting 250 km west of the rise and 340 km east of the rise, in contrast to the predicted trend of increasing depth to basement from cooling models of the oceanic lithosphere. The gradual increase in apparent crustal thickness and the shallowing trend of basement depth are interpreted to indicate that the deep distal parts of Cayman Trough are underlain by highly attenuated crust, not by a continuously accreted oceanic crust.
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Geochemical and Rheological Constraints on the Dynamics of the Oceanic Upper Mantle
2007-09-01
405-412. 201 Dick, H. J. B., Natland, J., Party, L. . S., 1994. Melt transport and evolution in the shallow mantle beneath the East Pacific Rise ...in the shallow mantle beneath the East Pacific Rise . In: M6vel, C., Gillis, K. M., Allan, J. F., Meyer, P. S. (Eds.), Proceedings of the Ocean...according to ridge location: East Pacific Rise (EPR), Mid-Cayman Rise (MCR), Central Indian Ridge/Carlsberg Ridge (CIR/Carl), Mid-Atlantic Ridge (MAR
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Natural and Man-Made Hazards in the Cayman Islands
NASA Astrophysics Data System (ADS)
Novelo-Casanova, D. A.; Suarez, G.
2010-12-01
Located in the western Caribbean Sea to the northwest of Jamaica, the Cayman Islands are a British overseas territory comprised of three islands: Grand Cayman, Cayman Brac, and Little Cayman. These three islands occupy around 250 km2 of land area. In this work, historical and recent data were collected and classified to identify and rank the natural and man-made hazards that may potentially affect the Cayman Islands and determine the level of exposure of Grand Cayman to these events. With this purpose, we used the vulnerability assessment methodology developed by the North Caroline Department of Environment and Natural Resources. The different degrees of physical vulnerability for each hazard were graphically interpreted with the aid of maps using a relative scoring system. Spatial maps were generated showing the areas of different levels of exposure to multi-hazards. The more important natural hazard to which the Cayman Islands are exposed is clearly hurricanes. To a lesser degree, the islands may be occasionally exposed to earthquakes and tsunamis. Explosions or leaks of the Airport Texaco Fuel Depot and the fuel pipeline at Grand Cayman are the most significant man-made hazards. Our results indicate that there are four areas in Grand Cayman with various levels of exposure to natural and man-made hazards: The North Sound, Little Sound and Eastern West Bay (Area 1) show a very high level of exposure; The Central Mangroves, Central Bodden Town, Central George Town and the West Bay (Area 2) have high level of exposure; The Northwestern West Bay, Western Georgetown-Bodden Town, and East End-North Side (Area 3) are under moderate levels of exposure. The remainder of the island shows low exposure (Area 4). It is important to underline that this study presents a first evaluation of the main natural and man-made hazards that may affect the Cayman Islands. The maps generated will be useful tools for emergency managers and policy developers and will increase the overall
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Reveillaud, Julie; Reddington, Emily; McDermott, Jill; Algar, Christopher; Meyer, Julie L.; Sylva, Sean; Seewald, Jeffrey; German, Christopher R.
2016-01-01
Summary Warm fluids emanating from hydrothermal vents can be used as windows into the rocky subseafloor habitat and its resident microbial community. Two new vent systems on the Mid‐Cayman Rise each exhibits novel geologic settings and distinctively hydrogen‐rich vent fluid compositions. We have determined and compared the chemistry, potential energy yielding reactions, abundance, community composition, diversity, and function of microbes in venting fluids from both sites: Piccard, the world's deepest vent site, hosted in mafic rocks; and Von Damm, an adjacent, ultramafic‐influenced system. Von Damm hosted a wider diversity of lineages and metabolisms in comparison to Piccard, consistent with thermodynamic models that predict more numerous energy sources at ultramafic systems. There was little overlap in the phylotypes found at each site, although similar and dominant hydrogen‐utilizing genera were present at both. Despite the differences in community structure, depth, geology, and fluid chemistry, energetic modelling and metagenomic analysis indicate near functional equivalence between Von Damm and Piccard, likely driven by the high hydrogen concentrations and elevated temperatures at both sites. Results are compared with hydrothermal sites worldwide to provide a global perspective on the distinctiveness of these newly discovered sites and the interplay among rocks, fluid composition and life in the subseafloor. PMID:26663423
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Deciphering MCR-2 Colistin Resistance
Sun, Jian; Xu, Yongchang; Gao, Rongsui; Lin, Jingxia; Wei, Wenhui; Srinivas, Swaminath; Li, Defeng; Yang, Run-Shi; Li, Xing-Ping; Liao, Xiao-Ping
2017-01-01
ABSTRACT Antibiotic resistance is a prevalent problem in public health worldwide. In general, the carbapenem β-lactam antibiotics are considered a final resort against lethal infections by multidrug-resistant bacteria. Colistin is a cationic polypeptide antibiotic and acts as the last line of defense for treatment of carbapenem-resistant bacteria. Very recently, a new plasmid-borne colistin resistance gene, mcr-2, was revealed soon after the discovery of the paradigm gene mcr-1, which has disseminated globally. However, the molecular mechanisms for MCR-2 colistin resistance are poorly understood. Here we show a unique transposon unit that facilitates the acquisition and transfer of mcr-2. Evolutionary analyses suggested that both MCR-2 and MCR-1 might be traced to their cousin phosphoethanolamine (PEA) lipid A transferase from a known polymyxin producer, Paenibacillus. Transcriptional analyses showed that the level of mcr-2 transcripts is relatively higher than that of mcr-1. Genetic deletions revealed that the transmembrane regions (TM1 and TM2) of both MCR-1 and MCR-2 are critical for their location and function in bacterial periplasm, and domain swapping indicated that the TM2 is more efficient than TM1. Matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) confirmed that all four MCR proteins (MCR-1, MCR-2, and two chimeric versions [TM1-MCR-2 and TM2-MCR-1]) can catalyze chemical modification of lipid A moiety anchored on lipopolysaccharide (LPS) with the addition of phosphoethanolamine to the phosphate group at the 4′ position of the sugar. Structure-guided site-directed mutagenesis defined an essential 6-residue-requiring zinc-binding/catalytic motif for MCR-2 colistin resistance. The results further our mechanistic understanding of transferable colistin resistance, providing clues to improve clinical therapeutics targeting severe infections by MCR-2-containing pathogens. PMID:28487432
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77 FR 38085 - Manufacturer of Controlled Substances; Notice of Registration; Cayman Chemical Company
Federal Register 2010, 2011, 2012, 2013, 2014
2012-06-26
...; Notice of Registration; Cayman Chemical Company By Notice dated March 8, 2012, and published in the Federal Register on March 20, 2012, 77 FR 16263, Cayman Chemical Company, 1180 East Ellsworth Road, Ann... registration of Cayman Chemical Company to manufacture the listed basic classes of controlled substances is...
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Reveillaud, Julie; Reddington, Emily; McDermott, Jill; Algar, Christopher; Meyer, Julie L; Sylva, Sean; Seewald, Jeffrey; German, Christopher R; Huber, Julie A
2016-06-01
Warm fluids emanating from hydrothermal vents can be used as windows into the rocky subseafloor habitat and its resident microbial community. Two new vent systems on the Mid-Cayman Rise each exhibits novel geologic settings and distinctively hydrogen-rich vent fluid compositions. We have determined and compared the chemistry, potential energy yielding reactions, abundance, community composition, diversity, and function of microbes in venting fluids from both sites: Piccard, the world's deepest vent site, hosted in mafic rocks; and Von Damm, an adjacent, ultramafic-influenced system. Von Damm hosted a wider diversity of lineages and metabolisms in comparison to Piccard, consistent with thermodynamic models that predict more numerous energy sources at ultramafic systems. There was little overlap in the phylotypes found at each site, although similar and dominant hydrogen-utilizing genera were present at both. Despite the differences in community structure, depth, geology, and fluid chemistry, energetic modelling and metagenomic analysis indicate near functional equivalence between Von Damm and Piccard, likely driven by the high hydrogen concentrations and elevated temperatures at both sites. Results are compared with hydrothermal sites worldwide to provide a global perspective on the distinctiveness of these newly discovered sites and the interplay among rocks, fluid composition and life in the subseafloor. © 2015 The Authors. Environmental Microbiology published by Society for Applied Microbiology and John Wiley & Sons Ltd.
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Magnetic anomaly map of the central Cayman Trough, northwestern Caribbean Sea
Dillon, William P.; Edgar, N. Terence; Parson, Lindsay M.; Scanlon, Kathryn M.; Driscoll, George R.; Jacobs, Colin L.
1993-01-01
This is the first large-scale published map of magnetic anomalies in the central Cayman Trough area. Two previously published very small scale maps based on much less data are a regional map (Gough and Heirtzler, 1969) and a map compiled from several tracklines running parallel to the axis of the Cayman Trough (MacDonald and Holcombe, 1978).
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Zhao, Feifei; Feng, Yu; Lü, Xiaoju; McNally, Alan; Zong, Zhiyong
2017-01-01
The plasmid-borne colistin-resistant gene mcr-1 has rapidly become a worldwide public health concern. This study aims to determine the host bacterial strains, plasmids, and genetic contexts of mcr-1 in hospital sewage. A 1-ml hospital sewage sample was cultured. Colistin-resistant bacterial colonies were selected on agar plates and were subjected to whole genome sequencing and subsequent analysis. The transfer of mcr-1 between bacterial strains was tested using conjugation. New variants of mcr-1 were cloned to test the impact of variations on the function of mcr-1 . Plasmids carrying mcr-1 were retrieved from GenBank for comparison based on concatenated backbone genes. In the sewage sample, we observed that mcr-1 was located in various genetic contexts on the chromosome, or plasmids of four different replicon types (IncHI2, IncI2, IncP, and IncX4), in Klebsiella pneumoniae, Kluyvera spp. and seven Escherichia coli strains of six different sequence types (ST10, ST34, ST48, ST1196, ST7086, and ST7087). We also identified two new variants of mcr-1, mcr-1.4 and mcr-1.7 , both of which encode an amino acid variation from mcr-1 . mcr-1 -carrying IncX4 plasmids, which have a global distribution across the Enterobacteriaceae , are the result of global dissemination of a single common plasmid, while IncI2 mcr-1 plasmids appear to acquire mcr-1 in multiple events. In conclusion, the unprecedented remarkable diversity of species, strains, plasmids, and genetic contexts carrying mcr-1 present in a single sewage sample from a single healthcare site highlights the continued evolution and dynamic transmission of mcr-1 in healthcare-associated environments.
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77 FR 47115 - Manufacturer of Controlled Substances; Notice of Application; Cayman Chemical Company
Federal Register 2010, 2011, 2012, 2013, 2014
2012-08-07
... DEPARTMENT OF JUSTICE Drug Enforcement Administration Manufacturer of Controlled Substances; Notice of Application; Cayman Chemical Company Pursuant to Sec. 1301.33(a), Title 21 of the Code of Federal Regulations (CFR), this is notice that on June 1, 2012, Cayman Chemical Company, 1180 East...
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AbuOun, Manal; Stubberfield, Emma J; Duggett, Nick A; Kirchner, Miranda; Dormer, Luisa; Nunez-Garcia, Javier; Randall, Luke P; Lemma, Fabrizio; Crook, Derrick W; Teale, Christopher; Smith, Richard P; Anjum, Muna F
2017-10-01
To determine the occurrence of mcr-1 and mcr-2 genes in Gram-negative bacteria isolated from healthy pigs in Great Britain. Gram-negative bacteria (n = 657) isolated from pigs between 2014 and 2015 were examined by WGS. Variants of mcr-1 and mcr-2 were identified in Moraxella spp. isolated from pooled caecal contents of healthy pigs at slaughter collected from six farms in Great Britain. Other bacteria, including Escherichia coli from the same farms, were not detected harbouring mcr-1 or mcr-2. A Moraxella porci-like isolate, MSG13-C03, harboured MCR-1.10 with 98.7% identity to MCR-1, and a Moraxella pluranimalium-like isolate, MSG47-C17, harboured an MCR-2.2 variant with 87.9% identity to MCR-2, from E. coli; the isolates had colistin MICs of 1-2 mg/L. No intact insertion elements were identified in either MSG13-C03 or MSG47-C17, although MSG13-C03 harboured the conserved nucleotides abutting the ISApl1 composite transposon found in E. coli plasmids and the intervening ∼2.6 kb fragment showed 97% identity. Six Moraxella osloensis isolates were positive for phosphoethanolamine transferase (EptA). They shared 62%-64.5% identity to MCR-1 and MCR-2, with colistin MICs from 2 to 4 mg/L. Phylogenetic analysis indicated that MCR and EptA have evolved from a common ancestor. In addition to mcr, the β-lactamase gene, blaBRO-1, was found in both isolates, whilst the tetracycline resistance gene, tetL, was found in MSG47-C17. Our results add further evidence for the mobilization of the mcr-pap2 unit from Moraxella via composite transposons leading to its global dissemination. The presence of mcr-pap2 from recent Moraxella isolates indicates they may comprise a reservoir for mcr. © Crown Copyright 2017.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Haas, Nicholas Q; Gillen, Robert E; Karnowski, Thomas P
MathWorks' MATLAB is widely used in academia and industry for prototyping, data analysis, data processing, etc. Many users compile their programs using the MATLAB Compiler to run on workstations/computing clusters via the free MATLAB Compiler Runtime (MCR). The MCR facilitates the execution of code calling Application Programming Interfaces (API) functions from both base MATLAB and MATLAB toolboxes. In a Linux environment, a sizable number of third-party runtime dependencies (i.e. shared libraries) are necessary. Unfortunately, to the MTLAB community's knowledge, these dependencies are not documented, leaving system administrators and/or end-users to find/install the necessary libraries either as runtime errors resulting frommore » them missing or by inspecting the header information of Executable and Linkable Format (ELF) libraries of the MCR to determine which ones are missing from the system. To address various shortcomings, Docker Images based on Community Enterprise Operating System (CentOS) 7, a derivative of Redhat Enterprise Linux (RHEL) 7, containing recent (2015-2017) MCR releases and their dependencies were created. These images, along with a provided sample Docker Compose YAML Script, can be used to create a simulated computing cluster where MATLAB Compiler created binaries can be executed using a sample Slurm Workload Manager script.« less
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SeaMARC II mapping of transform faults in the Cayman Trough, Caribbean Sea
Rosencrantz, Eric; Mann, Paul
1992-01-01
SeaMARC II maps of the southern wall of the Cayman Trough between Honduras and Jamaica show zones of continuous, well-defined fault lineaments adjacent and parallel to the wall, both to the east and west of the Cayman spreading axis. These lineaments mark the present, active traces of transform faults which intersect the southern end of the spreading axis at a triple junction. The Swan Islands transform fault to the west is dominated by two major lineaments that overlap with right-stepping sense across a large push-up ridge beneath the Swan Islands. The fault zone to the east of the axis, named the Walton fault, is more complex, containing multiple fault strands and a large pull-apart structure. The Walton fault links the spreading axis to Jamaican and Hispaniolan strike-slip faults, and it defines the southern boundary of a microplate composed of the eastern Cayman Trough and western Hispaniola. The presence of this microplate raises questions about the veracity of Caribbean plate velocities based primarily on Cayman Trough opening rates.
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NASA Astrophysics Data System (ADS)
Hsia, S.; Ouellette, G., Jr.; Manfrino, C.
2016-12-01
The Cayman Islands are situated in the west-central Caribbean Sea, between Cuba and the Yucatan Peninsula. Little Cayman Island (LCI) is relatively underdeveloped and understudied in comparison to its sister islands, Grand Cayman and Cayman Brac, and hosts less than 200 permanent residents over a 30 square kilometer area. However, like its sister islands, LCI is a small carbonate platform derived from reef building during the Oligocene, Miocene, and Quaternary. The shared geologic history of the Cayman Islands along with minimal human disturbance makes LCI an ideal site to study an island karst landscape. Conduction of field surveys, stratigraphic and petrologic comparisons between primary lithologic formations, and compilation of a geospatial inventory of karst features and lithology of LCI using GIS revealed novel insights into landscape evolution on LCI. In addition to surface karst surveys, several caves on the island were mapped. Cave morphologies suggest that evolution of LCI karst features have been driven by both hydroclimate, as well as salt and freshwater mixing, modulated by sea level fluctuations. These findings are mirrored in the lithology of partially dolomitized Miocene carbonates, which contain paleo-karst fill features and reveal hydroclimate influence, as well as enhanced resistance to dissolution in the present day, ostensibly from submersion in Mg-rich sea waters prior to the Quaternary. These findings shed light on the complex relationship of climate, geology, and karst landscape development on this particular carbonate island. This information is critical in anticipating structural and hydrogeological integrity on LCI under future climate change scenarios and serves as an example of the interplay linking climate and geologic processes to karst landscape development on small carbonate islands.
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Dissemination and Mechanism for the MCR-1 Colistin Resistance
Wang, Qingjing; Lin, Jingxia; Ye, Huiyan; Liu, Fei; Srinivas, Swaminath; Li, Defeng; Zhu, Baoli; Liu, Ya-Hong; Tian, Guo-Bao; Feng, Youjun
2016-01-01
Polymyxins are the last line of defense against lethal infections caused by multidrug resistant Gram-negative pathogens. Very recently, the use of polymyxins has been greatly challenged by the emergence of the plasmid-borne mobile colistin resistance gene (mcr-1). However, the mechanistic aspects of the MCR-1 colistin resistance are still poorly understood. Here we report the comparative genomics of two new mcr-1-harbouring plasmids isolated from the human gut microbiota, highlighting the diversity in plasmid transfer of the mcr-1 gene. Further genetic dissection delineated that both the trans-membrane region and a substrate-binding motif are required for the MCR-1-mediated colistin resistance. The soluble form of the membrane protein MCR-1 was successfully prepared and verified. Phylogenetic analyses revealed that MCR-1 is highly homologous to its counterpart PEA lipid A transferase in Paenibacili, a known producer of polymyxins. The fact that the plasmid-borne MCR-1 is placed in a subclade neighboring the chromosome-encoded colistin-resistant Neisseria LptA (EptA) potentially implies parallel evolutionary paths for the two genes. In conclusion, our finding provids a first glimpse of mechanism for the MCR-1-mediated colistin resistance. PMID:27893854
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NASA Astrophysics Data System (ADS)
Anderson, R. E.; Eren, A. M.; Stepanauskas, R.; Huber, J. A.; Reveillaud, J.
2015-12-01
Deep-sea hydrothermal vent systems serve as windows to a dynamic, gradient-dominated deep biosphere that is home to a wide diversity of archaea, bacteria, and viruses. Until recently the majority of these microbial lineages were uncultivated, resulting in a poor understanding of how the physical and geochemical context shapes microbial evolution in the deep subsurface. By comparing metagenomes, metatranscriptomes and single-cell genomes between geologically distinct vent fields, we can better understand the relationship between the environment and the evolution of subsurface microbial communities. An ideal setting in which to use this approach is the Mid-Cayman Rise, located on the world's deepest and slowest-spreading mid-ocean ridge, which hosts both the mafic-influenced Piccard and ultramafic-influenced Von Damm vent fields. Previous work has shown that Von Damm has higher taxonomic and metabolic diversity than Piccard, consistent with geochemical model expectations, and the fluids from all vents are enriched in hydrogen (Reveillaud et al., submitted). Mapping of both metagenomes and metatranscriptomes to a combined assembly showed very little overlap among the Von Damm samples, indicating substantial variability that is consistent with the diversity of potential metabolites in this ultramafic vent field. In contrast, the most consistently abundant and active lineage across the Piccard samples was Sulfurovum, a sulfur-oxidizing chemolithotroph that uses nitrate or oxygen as an electron acceptor. Moreover, analysis of point mutations within individual lineages suggested that Sulfurovumat Piccard is under strong selection, whereas microbial genomes at Von Damm were more variable. These results are consistent with the hypothesis that the subsurface environment at Piccard supports the emergence of a dominant lineage that is under strong selection pressure, whereas the more geochemically diverse microbial habitat at Von Damm creates a wider variety of stable
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Chan, Wai-Sing; Au, Chun-Hang; Ho, Dona N; Chan, Tsun-Leung; Ma, Edmond Shiu-Kwan; Tang, Bone Siu-Fai
2018-02-13
Human fecal carriage of Enterobacteriaceae possessing mobilized colistin resistance genes (mcr-1 and mcr-2) remains obscure in Hong Kong. As part of routine surveillance on emerging antibiotic resistance, we conducted a prospective study on this topic in a regional hospital in Hong Kong. From October 31 to November 25, 2016, all fecal specimens submitted for routine analysis were included in this surveillance study. These comprised 672 consecutive routine fecal specimens collected from 616 individuals. Fecal specimens were screened for colistin-resistant Enterobacteriaceae by culture-based method, and the presence of mcr-1 and mcr-2 genes in resistant isolates was identified by polymerase chain reaction and Sanger sequencing. Whole genome sequencing (WGS) of mcr-1-possessing Escherichia coli strains was facilitated using Illumina® MiSeq® followed by sequence analysis with appropriate bioinformatics tools. Fourteen mcr-1-positive E. coli strains were isolated from 14 separate individuals (2.08% of total fecal specimens), with 9 of them being asymptomatic, healthy clients coming for health assessment. No mcr-2-possessing Enterobacteriaceae was identified. Colistin minimum inhibitory concentrations of these mcr-1-positive isolates ranged from 2 to 4 μg/mL. All these isolates were susceptible to carbapenems with 2 being extended spectrum β-lactamase producers. WGS data revealed that these isolates belonged to at least 12 different sequence types (STs) and possessed diversified plasmid replicons, virulence and acquired antibiotic resistance genes. Further study on an E. coli ST201 strain (Pasteur scheme) revealed coexistence of 47,818-bp IncP-1 and 33,309-bp IncX4 types of mcr-1 plasmids, which was a combination of stability and high transmissibility. To the best of our knowledge, this is the first study on human fecal carriage of Enterobacteriaceae possessing mcr-1 and mcr-2 genes in Hong Kong. Our data further revealed asymptomatic carriage of mcr-1-possessing
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Sarı, Ayşe Nur; Süzük, Serap; Karatuna, Onur; Öğünç, Dilara; Karakoç, Ayşe Esra; Çizmeci, Zeynep; Alışkan, Hikmet Eda; Cömert, Füsun; Bakıcı, Mustafa Zahir; Akpolat, Nezahat; Çilli, Fatma Feriha; Zer, Yasemin; Karataş, Aysel; Akgün Karapınar, Bahar; Bayramoğlu, Gülçin; Özdamar, Melda; Kalem, Fatma; Delialioğlu, Nuran; Aktaş, Elif; Yılmaz, Nisel; Gürcan, Şaban; Gülay, Zeynep
2017-07-01
Colistin is a polymyxin antibiotic which is considered as one of the last line agents against infections due to multidrug resistant or carbapenem resistant gram-negative pathogens. Colistin resistance is associated with chromosomal alterations which can usually cause mutations in genes coding specific two component regulator systems. The first plasmid-mediated colistin resistance gene, mcr-1 was described in Escherichia coli and Klebsiella pneumoniae isolates in December 2015 and followed by another plasmid-mediated colistin resistance gene mcr-2 in 2016. The rapid and interspecies dissemination of plasmid-mediated resistance mechanisms through horizontal gene transfer, have made these genes considerably threatening. After the first reports, although mcr-1/mcr-2 producing Enterobacteriaceae isolates have been reported from many countries, there have been no reports from Turkey. Thus, the aim of this study was to investigate the presence of mcr-1/mcr-2 in clinical Enterobacteriaceae isolates from different parts of our country. A total of 329 Enterobacteriaceae isolates from 22 laboratories were collected which were isolated between March, 2015 and February, 2016. mcr-1/mcr-2 were investigated by polymerase chain reaction during February-March, 2016. Two hundred and seventeen of Klebsiella pneumoniae (66%), 75 of Salmonella spp. (22.8%), 31 of Esherichia coli (9.4%), 3 of Enterobacter cloacae (0.9%), 2 of Klebsiella oxytoca (0.6%) and 1 of Enterobacter aerogenes (0.3%) isolates were included to the study. Agarose gel electrophoresis results of PCR studies have shown expected band sizes for positive control isolates as 309 bp for mcr-1 and 567 bp for mcr-2. However, the presence of mcr-1/mcr-2 genes was not detected among the tested study isolates of Enterobacteriaceae. Although mcr-1/mcr-2 were not detected in our study isolates, it is highly important to understand the mechanism of resistance dissemination and determine the resistant isolates by considering that
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MCrAlY bond coat with enhanced Yttrium layer
Jablonski, Paul D; Hawk, Jeffrey A
2015-04-21
One or more embodiments relates to an MCrAlY bond coat comprising an MCrAlY layer in contact with a Y--Al.sub.2O.sub.3 layer. The MCrAlY layer is comprised of a .gamma.-M solid solution, a .beta.-MAl intermetallic phase, and Y-type intermetallics. The Y--Al.sub.2O.sub.3 layer is comprised of Yttrium atoms coordinated with oxygen atoms comprising the Al.sub.2O.sub.3 lattice. Both the MCrAlY layer and the Y--Al.sub.2O.sub.3 layer have a substantial absence of Y--Al oxides, providing advantage in the maintainability of the Yttrium reservoir within the MCrAlY bulk. The MCrAlY bond coat may be fabricated through application of a Y.sub.2O.sub.3 paste to an MCrAlY material, followed by heating in a non-oxidizing environment.
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Photoinactivation of mcr-1 positive Escherichia coli
NASA Astrophysics Data System (ADS)
Caires, C. S. A.; Leal, C. R. B.; Rodrigues, A. C. S.; Lima, A. R.; Silva, C. M.; Ramos, C. A. N.; Chang, M. R.; Arruda, E. J.; Oliveira, S. L.; Nascimento, V. A.; Caires, A. R. L.
2018-01-01
The emergence of plasmid-mediated colistin resistance in Enterobacteriaceae, mostly in Escherichia coli due to the mcr-1 gene, has revealed the need to develop alternative approaches in treating mcr-1 positive bacterial infections. This is because colistin is a broad-spectrum antibiotic and one of the ‘last-resort’ antibiotics for multidrug resistant bacteria. The present study evaluated for the first time, to the best of our knowledge, the efficacy of photoinactivation processes to kill a known mcr-1 positive E. coli strain. Eosin methylene-blue (EMB) was investigated as a photoantimicrobial agent for inhibiting the growth of a mcr-1 positive E. coli strain obtained from a patient with a diabetic foot infection. The photoantimicrobial activity of EMB was also tested in a non-multidrug resistant E. coli strain. The photoinactivation process was tested using light doses in the 30-45 J cm-2 range provided by a LED device emitting at 625 nm. Our findings demonstrate that a mcr-1 positive E. coli strain is susceptible to photoinactivation. The results show that the EMB was successfully photoactivated, regardless of the bacterial multidrug resistance; inactivating the bacterial growth by oxidizing the cells in accordance with the generation of the oxygen reactive species. Our results suggest that bacterial photoinactivation is an alternative and effective approach to kill mcr-1 positive bacteria.
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MCrAlY bond coat with enhanced yttrium
Jablonski, Paul D.; Hawk, Jeffrey A.
2016-08-30
One or more embodiments relates to a method of producing an MCrAlY bond coat comprising an MCrAlY layer in contact with a Y--Al.sub.2O.sub.3 layer. The MCrAlY layer is comprised of a .gamma.-M solid solution, a .beta.-MAl intermetallic phase, and Y-type intermetallics. The Y--Al.sub.2O.sub.3 layer is comprised of Yttrium atoms coordinated with oxygen atoms comprising the Al.sub.2O.sub.3 lattice. The method comprises depositing an MCrAlY material on a substrate, applying an Y.sub.2O.sub.3 paste, and heating the substrate in a non-oxidizing atmosphere at a temperature between 400-1300.degree. C. for a time sufficient to generate the Y--Al.sub.2O.sub.3 layer. Both the MCrAlY layer and the Y--Al.sub.2O.sub.3 layer have a substantial absence of Y.sub.2O.sub.3, YAG, and YAP phases.
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Gaseous modification of MCrAlY coatings
Vance, Steven J.; Goedjen, John G.; Sabol, Stephen M.; Sloan, Kelly M.
2000-01-01
The present invention generally describes methods for modifying MCrAlY coatings by using gaseous carburization, gaseous nitriding or gaseous carbonitriding. The modified MCrAlY coatings are useful in thermal barrier coating systems, which may be used in gas turbine engines.
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Hernández, Marta; Iglesias, M Rocío; Rodríguez-Lázaro, David; Gallardo, Alejandro; Quijada, Narciso M; Miguela-Villoldo, Pedro; Campos, Maria Jorge; Píriz, Segundo; López-Orozco, Gema; de Frutos, Cristina; Sáez, José Luis; Ugarte-Ruiz, María; Domínguez, Lucas; Quesada, Alberto
2017-01-01
Colistin resistance genes mcr-3 and mcr-1 have been detected in an Escherichia coli isolate from cattle faeces in a Spanish slaughterhouse in 2015. The sequences of both genes hybridised to same plasmid band of ca 250 kb, although colistin resistance was non-mobilisable. The isolate was producing extended-spectrum beta-lactamases and belonged to serotype O9:H10 and sequence type ST533. Here we report an mcr-3 gene detected in Europe following earlier reports from Asia and the United States. PMID:28797328
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Hernández, Marta; Iglesias, M Rocío; Rodríguez-Lázaro, David; Gallardo, Alejandro; Quijada, Narciso; Miguela-Villoldo, Pedro; Campos, Maria Jorge; Píriz, Segundo; López-Orozco, Gema; de Frutos, Cristina; Sáez, José Luis; Ugarte-Ruiz, María; Domínguez, Lucas; Quesada, Alberto
2017-08-03
Colistin resistance genes mcr-3 and mcr-1 have been detected in an Escherichia coli isolate from cattle faeces in a Spanish slaughterhouse in 2015. The sequences of both genes hybridised to same plasmid band of ca 250 kb, although colistin resistance was non-mobilisable. The isolate was producing extended-spectrum beta-lactamases and belonged to serotype O9:H10 and sequence type ST533. Here we report an mcr-3 gene detected in Europe following earlier reports from Asia and the United States. This article is copyright of The Authors, 2017.
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A simple phenotypic method for screening of MCR-1-mediated colistin resistance.
Coppi, M; Cannatelli, A; Antonelli, A; Baccani, I; Di Pilato, V; Sennati, S; Giani, T; Rossolini, G M
2018-02-01
To evaluate a novel method, the colistin-MAC test, for phenotypic screening of acquired colistin resistance mediated by transferable mcr-1 resistance determinants, based on colistin MIC reduction in the presence of dipicolinic acid (DPA). The colistin-MAC test consists in a broth microdilution method, in which colistin MIC is tested in the absence or presence of DPA (900 μg/mL). Overall, 74 colistin-resistant strains of Enterobacteriaceae (65 Escherichia coli and nine other species), including 61 strains carrying mcr-1-like genes and 13 strains negative for mcr genes, were evaluated with the colistin-MAC test. The presence of mcr-1-like and mcr-2-like genes was assessed by real-time PCR and end-point PCR. For 20 strains, whole-genome sequencing data were also available. A ≥8-fold reduction of colistin MIC in the presence of DPA was observed with 59 mcr-1-positive strains, including 53 E. coli of clinical origin, three E. coli transconjugants carrying MCR-1-encoding plasmids, one Enterobacter cloacae complex and two Citrobacter spp. Colistin MICs were unchanged, increased or at most reduced by twofold with the 13 mcr-negative colistin-resistant strains (nine E. coli and four Klebsiella pneumoniae), but also with two mcr-1-like-positive K. pneumoniae strains. The colistin-MAC test could be a simple phenotypic test for presumptive identification of mcr-1-positive strains among isolates of colistin-resistant E. coli, based on a ≥8-fold reduction of colistin MIC in the presence of DPA. Evaluation of the test with a larger number of strains, species and mcr-type resistance determinants would be of interest. Copyright © 2017 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.
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Spread of mcr-1-carrying Enterobacteriaceae in sewage water from Spain.
Ovejero, C M; Delgado-Blas, J F; Calero-Caceres, W; Muniesa, M; Gonzalez-Zorn, B
2017-04-01
The mobile colistin resistance gene mcr-1 has been identified worldwide in human and animal sources, while its occurrence in the environment is still largely unknown. The aim of this study was to investigate the presence of mcr-1 -harbouring Enterobacteriaceae in water samples obtained from rivers and waste water treatment plants in the area of Barcelona, Spain. The presence of mcr-1 was detected by PCR. Bacterial identification was performed via MALDI-TOF MS. Resistance to colistin was determined by a broth dilution method. The epidemiological relationship between the positive isolates was assessed with PFGE and ST was determined by MLST. Plasmid characterization was performed by transformation experiments, antimicrobial susceptibility testing and incompatibility group PCR. Thirty MDR isolates bearing mcr-1 , 29 Escherichia coli (ST632 and ST479) and 1 Klebsiella pneumoniae (ST526), were identified in sewage from two different waste water treatment plants, whereas the gene was not found in river water. All isolates, including the K. pneumoniae , harboured bla CTX-M-55 and bla TEM-1 . mcr-1 was in all cases associated with an IncI2 plasmid, which only conferred resistance to colistin. mcr-1 was harboured by two predominant E. coli clones that were found in both waste water treatment plants. This study showed a high occurrence of mcr-1 in the sewage of Barcelona, mainly due to the dissemination of two E. coli pulsotypes that are circulating in the population. The presence of mcr-1 in the environment is a cause for concern, and suggests high prevalence of mcr-1 in the community. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
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Transferability of MCR-1/2 Polymyxin Resistance: Complex Dissemination and Genetic Mechanism.
Feng, Youjun
2018-03-09
Polymyxins, a group of cationic antimicrobial polypeptides, act as a last-resort defense against lethal infections by carbapenem-resistant Gram-negative pathogens. Recent emergence and fast spread of mobilized colistin resistance determinant mcr-1 argue the renewed interest of colistin in clinical therapies, threatening global public health and agriculture production. This mini-review aims to present an updated overview of mcr-1, covering its global dissemination, the diversity of its hosts/plasmid reservoirs, the complexity in the genetic environment adjacent to mcr-1, the appearance of new mcr-like genes, and the molecular mechanisms for mobilized colistin resistance determinant 1/2 (MCR-1/2).
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Moraxella Species as Potential Sources of MCR-Like Polymyxin Resistance Determinants
Kieffer, Nicolas; Nordmann, Patrice
2017-01-01
ABSTRACT Plasmid-mediated resistance to polymyxins mediated by the MCR-1/2 determinants has been reported in Enterobacteriaceae worldwide. Using PCR-based and cloning strategies, a series of Moraxella spp. were screened for mcr-like genes. Moraxella spp. that are mainly animal pathogens but may also be human pathogens were identified as potential reservoirs of mcr-like genes. PMID:28320720
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Electrodeposited MCrAlY Coatings for Gas Turbine Engine Applications
NASA Astrophysics Data System (ADS)
Zhang, Y.
2015-11-01
Electrolytic codeposition is a promising alternative process for fabricating MCrAlY coatings. The coating process involves two steps, i.e., codeposition of CrAlY-based particles and a metal matrix of Ni, Co, or (Ni,Co), followed by a diffusion heat treatment to convert the composite coating to the desired MCrAlY microstructure. Despite the advantages such as low cost and non-line-of-sight, this coating process is less known than electron beam-physical vapor deposition and thermal spray processes for manufacturing high-temperature coatings. This article provides an overview of the electro-codeposited MCrAlY coatings for gas turbine engine applications, highlighting the unique features of this coating process and some important findings in the past 30 years. Challenges and research opportunities for further optimization of this type of MCrAlY coatings are also discussed.
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Molecular characteristic of mcr-1 producing Escherichia coli in a Chinese university hospital.
He, Qing-Wen; Xu, Xiao-Hong; Lan, Fang-Jun; Zhao, Zhi-Chang; Wu, Zhi-Yun; Cao, Ying-Ping; Li, Bin
2017-04-19
Colistin has been considered as a last-line treatment option in severe infections caused by multidrug-resistant (MDR) gram-negative pathogens. However, the emergence of the mobile colistin resistance gene (mcr-1) has challenged this viewpoint. The aim of this study is to explore the prevalence of mcr-1 in Escherichia coli (E. coli) in a Chinese teaching hospital, and investigate their molecular characteristics. A total of 700 E. coli isolates were used to screen mcr-1 by PCR and sequencing in a Chinese university hospital from August 2014 to August 2015. Susceptibility test of mcr-1-producing isolates was determined by Vitek -2 Compact system. 26 virulence factors (VFs), phylogenetic groups, Multi-locus sequence typing (MLST), and DNA Fingerprinting (ERIC-PCR) of strains were investigated by PCR. Four (0.6%) mcr-1 producing E. coli isolates were found in this study. The results of antibiotic susceptibility test showed that all four isolates were resistant to colistin, ciprofloxacin, levofloxacin, cefazolin, and trimethoprim/sulfamethoxazole, and were susceptible to amikacin, ertapenem and imipenem. In addition, all 4 isolates exhibited high-level resistance to aztreonam, cefotaxime and gentamicin. The numbers of VFs contained in mcr-1 positive isolates were no more than 4 in our study. MLST result demonstrated that these isolates were assigned to two sequence types: ST156 and ST167. The result of phylogenetic analysis showed that four mcr-1-positive isolates belong to two phylogenetic groups: A and B1 group. ERIC-PCR showed that four mcr-1 positive strains were categorized into three different genotypes. Our study demonstrated a low prevalence of mcr-1 in E. coli clinical isolates in a Chinese teaching hospital, and we have gained insights into the molecular characteristics of these mcr-1-positive strains. Increasing the surveillance of these infections, as well as taking effective infection control measures are urgently needed to take to control the transmission
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NASA Astrophysics Data System (ADS)
McDermott, Jill M.; Sylva, Sean P.; Ono, Shuhei; German, Christopher R.; Seewald, Jeffrey S.
2018-05-01
Hosted in basaltic substrate on the ultra-slow spreading Mid-Cayman Rise, the Piccard hydrothermal field is the deepest currently known seafloor hot-spring (4957-4987 m). Due to its great depth, the Piccard site is an excellent natural system for investigating the influence of extreme pressure on the formation of submarine vent fluids. To investigate the role of rock composition and deep circulation conditions on fluid chemistry, the abundance and isotopic composition of organic, inorganic, and dissolved volatile species in high temperature vent fluids at Piccard were examined in samples collected in 2012 and 2013. Fluids from the Beebe Vents and Beebe Woods black smokers vent at a maximum temperature of 398 °C at the seafloor, however several lines of evidence derived from inorganic chemistry (Cl, SiO2, Ca, Br, Fe, Cu, Mn) support fluid formation at much higher temperatures in the subsurface. These high temperatures, potentially in excess of 500 °C, are attainable due to the great depth of the system. Our data indicate that a single deep-rooted source fluid feeds high temperature vents across the entire Piccard field. High temperature Piccard fluid H2 abundances (19.9 mM) are even higher than those observed in many ultramafic-influenced systems, such as the Rainbow (16 mM) and the Von Damm hydrothermal fields (18.2 mM). In the case of Piccard, however, these extremely high H2 abundances can be generated from fluid-basalt reaction occurring at very high temperatures. Magmatic and thermogenic sources of carbon in the high temperature black smoker vents are described. Dissolved ΣCO2 is likely of magmatic origin, CH4 may originate from a combination of thermogenic sources and leaching of abiotic CH4 from mineral-hosted fluid inclusions, and CO abundances are at equilibrium with the water-gas shift reaction. Longer-chained n-alkanes (C2H6, C3H8, n-C4H10, i-C4H10) may derive from thermal alteration of dissolved and particulate organic carbon sourced from the original
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The first human report of mobile colistin resistance gene, mcr-1, in Finland.
Gröndahl-Yli-Hannuksela, Kirsi; Lönnqvist, Emilia; Kallonen, Teemu; Lindholm, Laura; Jalava, Jari; Rantakokko-Jalava, Kaisu; Vuopio, Jaana
2018-05-01
Colistin resistance mediated by mobile mcr-1 gene has raised concern during the last years. After steep increase in mcr-1 reports, other mcr-gene variants (mcr-2 to mcr-5) have been revealed as well. In 2016, a clinical study was conducted on asymptomatic stool carriage of extended spectrum beta-lactamase (ESBL) producing Escherichia coli and Klebsiella pneumoniae among Finnish adults. All suspected ESBL producing bacterial isolates were first tested by phenotypic ESBL-confirmation methods, and then further analyzed with whole genome sequencing to identify the resistance genes. We found one study subject carrying a colistin resistant E. coli with a transferrable mcr-1 gene. This multi-drug resistant isolate, although initially suspected to be an ESBL producer, did not carry any ESBL genes, but was proven to carry several other resistance genes by using whole genome sequencing. Sequence type was ST93. The mcr-1 gene was connected to IncX4 plasmid which suggests that the colistin resistance gene locates in the respective plasmid. Here, we report the finding of a mcr-1 harboring human E. coli isolate from Finland. Clinical antimicrobial resistance (AMR) rates are low in Finland, and mobile colistin resistance has not been reported previously. This highlights the importance of AMR surveillance also in populations with low levels of resistance. © 2018 The Authors. APMIS published by John Wiley & Sons Ltd on behalf of Scandinavian Societies for Medical Microbiology and Pathology.
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USDA-ARS?s Scientific Manuscript database
The rapid spreading of polymyxin E (colistin) resistance among bacterial strains through the horizontally transmissible mcr-1 and mcr-2 plasmids has become a serious concern. The emergence of these genes in Shiga toxin-producing Escherichia coli (STEC), a group of human pathogenic bacteria was even ...
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Headley, S A; Gillen, M A; Sanches, A W D; Satti, M Z
2012-06-01
The occurrence of platynosomiasis and intestinal sparganosis is described in feral cats from Grand Cayman, Cayman Islands. Spirometra spp. was observed within the intestine of 18.18% (10/55) of cats; 1.18% (1/55) of cats demonstrated gross and histological manifestation of parasitism by Platynosomum fastosum, but 14.5% (8/55) of cats had the characteristic pathological manifestations of P. fastosum-induced intrahepatic cholangitis without the concomitant presence of the intraductal trematode. Combined parasitism (Spirometra spp. and P. fastosum) was observed in 9.09% (5/55) of feral cats. Significant pathological findings were only associated with the hepatic fluke, P. fastosum, and were grossly characterized by moderate hepatomegaly with enlarged and dilated bile ducts. Examples of cestodes with morphological features characteristic of Spirometra spp. were observed within the small intestine without any associated pathological lesion. The histopathological evaluation of liver fragments revealed chronic intrahepatic cholangitis with and without the associated intraductal trematode, and was characterized by marked periductal fibrosis, adenomatous proliferation of bile duct epithelium, dilation of intrahepatic bile ducts and portal accumulations of inflammatory cells. The occurrence of the cestode in feral cats coupled with factors that are unique to Grand Cayman makes this island the ideal location for sporadic cases of human sparganosis.
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NASA Astrophysics Data System (ADS)
Streit, Kathrin; Bennett, Sarah A.; Van Dover, Cindy L.; Coleman, Max
2015-06-01
Hydrothermal vents harbor ecosystems mostly decoupled from organic carbon synthesized with the energy of sunlight (photosynthetic carbon source) but fueled instead by oxidation of reduced compounds to generate a chemosynthetic carbon source. Our study aimed to disentangle photosynthetic and chemosynthetic organic carbon sources for the shrimp species Rimicaris hybisae, a primary consumer presumed to obtain its organic carbon mainly from ectosymbiotic chemoautotrophic bacteria living on its gill cover membrane. To provide ectosymbionts with ideal conditions for chemosynthesis, these shrimp live in dense clusters around vent chimneys; they are, however, also found sparsely distributed adjacent to diffuse vent flows, where they might depend on alternative food sources. Densely and sparsely distributed shrimp were sampled and dissected into abdominal tissue and gill cover membrane, covered with ectosymbiotic bacteria, at two hydrothermal vent fields in the Mid-Cayman rise that differ in vent chemistry. Fatty acids (FA) were extracted from shrimp tissues and their carbon isotopic compositions assessed. The FA data indicate that adult R. hybisae predominantly rely on bacteria for their organic carbon needs. Their FA composition is dominated by common bacterial FA of the n7 family (~41%). Bacterial FA of the n4 FA family are also abundant and found to constitute good biomarkers for gill ectosymbionts. Sparsely distributed shrimp contain fractions of n4 FA in gill cover membranes ~4% lower than densely packed ones (~18%) and much higher fractions of photosynthetic FA in abdominal tissues, ~4% more (compared with 1.6%), suggesting replacement of ectosymbionts along with exoskeletons (molt), while they take up alternative diets of partly photosynthetic organic carbon. Abdominal tissues also contain photosynthetic FA from a second source taken up presumably during an early dispersal phase and still present to c. 3% in adult shrimp. The contribution of photosynthetic carbon to
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Oxidation resistant nanocrystalline MCrAl(Y) coatings and methods of forming such coatings
Cheruvu, Narayana S.; Wei, Ronghua
2014-07-29
The present disclosure relates to an oxidation resistant nanocrystalline coating and a method of forming an oxidation resistant nanocrystalline coating. An oxidation resistant coating comprising an MCrAl(Y) alloy may be deposited on a substrate, wherein M, includes iron, nickel, cobalt, or combinations thereof present greater than 50 wt % of the MCrAl(Y) alloy, chromium is present in the range of 15 wt % to 30 wt % of the MCrAl(Y) alloy, aluminum is present in the range of 6 wt % to 12 wt % of the MCrAl(Y) alloy and yttrium, is optionally present in the range of 0.1 wt % to 0.5 wt % of the MCrAl(Y) alloy. In addition, the coating may exhibit a grain size of 200 nm or less as deposited.
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Prevalence of mcr-1 in E. coli from Livestock and Food in Germany, 2010-2015.
Irrgang, Alexandra; Roschanski, Nicole; Tenhagen, Bernd-Alois; Grobbel, Mirjam; Skladnikiewicz-Ziemer, Tanja; Thomas, Katharina; Roesler, Uwe; Käsbohrer, Annemarie
2016-01-01
Since the first description of a plasmid-mediated colistin resistance gene (mcr-1) in November 2015 multiple reports of mcr-1 positive isolates indicate a worldwide spread of this newly discovered resistance gene in Enterobacteriaceae. Although the occurrence of mcr-1 positive isolates of livestock, food, environment and human origin is well documented only few systematic studies on the prevalence of mcr-1 are available yet. Here, comprehensive data on the prevalence of mcr-1 in German livestock and food isolates are presented. Over 10.600 E. coli isolates from the national monitoring on zoonotic agents from the years 2010-2015 were screened for phenotypic colistin resistance (MIC value >2 mg/l). Of those, 505 resistant isolates were screened with a newly developed TaqMan-based real-time PCR for the presence of the mcr-1 gene. In total 402 isolates (79.8% of colistin resistant isolates) harboured the mcr-1 gene. The prevalence was depending on the food production chain. The highest prevalence was detected in the turkey food chain (10.7%), followed by broilers (5.6%). A low prevalence was determined in pigs, veal calves and laying hens. The mcr-1 was not detected in beef cattle, beef and dairy products in all years investigated. In conclusion, TaqMan based real-time PCR provides a fast and accurate tool for detection of mcr-1 gene. The overall detection rate of 3.8% for mcr-1 among all E. coli isolates tested is due to high prevalence of mcr-1 in poultry production chains. More epidemiological studies of other European countries are urgently needed to assess German prevalence data.
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Structural Modification of Lipopolysaccharide Conferred by mcr-1 in Gram-Negative ESKAPE Pathogens.
Liu, Yi-Yun; Chandler, Courtney E; Leung, Lisa M; McElheny, Christi L; Mettus, Roberta T; Shanks, Robert M Q; Liu, Jian-Hua; Goodlett, David R; Ernst, Robert K; Doi, Yohei
2017-06-01
mcr-1 was initially reported as the first plasmid-mediated colistin resistance gene in clinical isolates of Escherichia coli and Klebsiella pneumoniae in China and has subsequently been identified worldwide in various species of the family Enterobacteriaceae mcr-1 encodes a phosphoethanolamine transferase, and its expression has been shown to generate phosphoethanolamine-modified bis-phosphorylated hexa-acylated lipid A in E. coli Here, we investigated the effects of mcr-1 on colistin susceptibility and on lipopolysaccharide structures in laboratory and clinical strains of the Gram-negative ESKAPE ( Enterococcus faecium , Staphylococcus aureus , K. pneumoniae , Acinetobacter baumannii , Pseudomonas aeruginosa , and Enterobacter species) pathogens, which are often treated clinically by colistin. The effects of mcr-1 on colistin resistance were determined using MIC assays of laboratory and clinical strains of E. coli , K. pneumoniae , A. baumannii , and P. aeruginosa Lipid A structural changes resulting from MCR-1 were analyzed by mass spectrometry. The introduction of mcr-1 led to colistin resistance in E. coli , K. pneumoniae , and A. baumannii but only moderately reduced susceptibility in P. aeruginosa Phosphoethanolamine modification of lipid A was observed consistently for all four species. These findings highlight the risk of colistin resistance as a consequence of mcr-1 expression among ESKAPE pathogens, especially in K. pneumoniae and A. baumannii Furthermore, the observation that lipid A structures were modified despite only modest increases in colistin MICs in some instances suggests more sophisticated surveillance methods may need to be developed to track the dissemination of mcr-1 or plasmid-mediated phosphoethanolamine transferases in general. Copyright © 2017 American Society for Microbiology.
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Structural Modification of Lipopolysaccharide Conferred by mcr-1 in Gram-Negative ESKAPE Pathogens
Liu, Yi-Yun; Chandler, Courtney E.; Leung, Lisa M.; McElheny, Christi L.; Mettus, Roberta T.; Liu, Jian-Hua; Goodlett, David R.
2017-01-01
ABSTRACT mcr-1 was initially reported as the first plasmid-mediated colistin resistance gene in clinical isolates of Escherichia coli and Klebsiella pneumoniae in China and has subsequently been identified worldwide in various species of the family Enterobacteriaceae. mcr-1 encodes a phosphoethanolamine transferase, and its expression has been shown to generate phosphoethanolamine-modified bis-phosphorylated hexa-acylated lipid A in E. coli. Here, we investigated the effects of mcr-1 on colistin susceptibility and on lipopolysaccharide structures in laboratory and clinical strains of the Gram-negative ESKAPE (Enterococcus faecium, Staphylococcus aureus, K. pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) pathogens, which are often treated clinically by colistin. The effects of mcr-1 on colistin resistance were determined using MIC assays of laboratory and clinical strains of E. coli, K. pneumoniae, A. baumannii, and P. aeruginosa. Lipid A structural changes resulting from MCR-1 were analyzed by mass spectrometry. The introduction of mcr-1 led to colistin resistance in E. coli, K. pneumoniae, and A. baumannii but only moderately reduced susceptibility in P. aeruginosa. Phosphoethanolamine modification of lipid A was observed consistently for all four species. These findings highlight the risk of colistin resistance as a consequence of mcr-1 expression among ESKAPE pathogens, especially in K. pneumoniae and A. baumannii. Furthermore, the observation that lipid A structures were modified despite only modest increases in colistin MICs in some instances suggests more sophisticated surveillance methods may need to be developed to track the dissemination of mcr-1 or plasmid-mediated phosphoethanolamine transferases in general. PMID:28373195
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Biogenicity of terrestrial oncoids formed in soil pockets, Cayman Brac, British West Indies
NASA Astrophysics Data System (ADS)
Jones, Brian
2011-05-01
Terrestrial oncoids, up to 85 mm long, are common in some of the soil-filled pockets found in the finely crystalline dolostones of the Cayman Formation on Cayman Brac. Each of these coated grains has a nucleus formed of a white, finely crystalline dolostone lithoclast (derived from the Cayman Formation) that is encased by a light brown to tan cortex that is formed largely of micrite and minimicrite, is vaguely laminated, and lacks obvious biogenic structures. The cortex, typically < 10 mm thick, is variable in thickness around individual grains and from grain to grain. On the surfaces of the oncoids there is a diverse microbiota that includes various reticulate filaments that are typically < 1 μm in diameter, cocci, some large-diameter collapsed and calcified filaments, sporangia-like structures, and locally, exopolysaccharides (EPS). In the subsurface parts of the cortices, however, filaments are very rare and there are only scattered cocci. Evidence derived from the surface microbes indicates that they played an active role in the growth of the cortical laminae by binding material to their surfaces, calcification of the microbes, providing substrates on which calcite was precipitated, and forming cavities in which calcite cement was later precipitated. In stark contrast, it is difficult to ascribe a biotic influence to the formation of the subsurface laminae because of the paucity of preserved microbes. The lack of microbes, however, probably reflects the fact that the formative microbes were destroyed during diagenesis. This example clearly demonstrates that the lack of preserved microbes cannot be taken as an indication that the grains formed as a result of abiogenic processes.
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NASA Astrophysics Data System (ADS)
von Reumont, J.; Hetzinger, S.; Garbe-Schönberg, D.; Manfrino, C.; Dullo, W.-Chr.
2016-03-01
The rising temperature of the world's oceans is affecting coral reef ecosystems by increasing the frequency and severity of bleaching and mortality events. The susceptibility of corals to temperature stress varies on local and regional scales. Insights into potential controlling parameters are hampered by a lack of long term in situ data in most coral reef environments and sea surface temperature (SST) products often do not resolve reef-scale variations. Here we use 42 years (1970-2012) of coral Sr/Ca data to reconstruct seasonal- to decadal-scale SST variations in two adjacent but distinct reef environments at Little Cayman, Cayman Islands. Our results indicate that two massive Diploria strigosa corals growing in the lagoon and in the fore reef responded differently to past warming events. Coral Sr/Ca data from the shallow lagoon successfully record high summer temperatures confirmed by in situ observations (>33°C). Surprisingly, coral Sr/Ca from the deeper fore reef is strongly affected by thermal stress events, although seasonal temperature extremes and mean SSTs at this site are reduced compared to the lagoon. The shallow lagoon coral showed decadal variations in Sr/Ca, supposedly related to the modulation of lagoonal temperature through varying tidal water exchange, influenced by the 18.6 year lunar nodal cycle. Our results show that reef-scale SST variability can be much larger than suggested by satellite SST measurements. Thus, using coral SST proxy records from different reef zones combined with in situ observations will improve conservation programs that are developed to monitor and predict potential thermal stress on coral reefs.
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Structure of the catalytic domain of the colistin resistance enzyme MCR-1
Stojanoski, Vlatko; Sankaran, Banumathi; Prasad, B. V. Venkataram; ...
2016-09-21
Due to the paucity of novel antibiotics, colistin has become a last resort antibiotic for treating multidrug resistant bacteria. Colistin acts by binding the lipid A component of lipopolysaccharides and subsequently disrupting the bacterial membrane. The recently identified plasmid-encoded MCR-1 enzyme is the first transmissible colistin resistance determinant and is a cause for concern for the spread of this resistance trait. MCR-1 is a phosphoethanolamine transferase that catalyzes the addition of phosphoethanolamine to lipid A to decrease colistin affinity. The structure of the catalytic domain of MCR-1 at 1.32 Å reveals the active site is similar to that of relatedmore » phosphoethanolamine transferases. The putative nucleophile for catalysis, threonine 285, is phosphorylated in cMCR-1 and a zinc is present at a conserved site in addition to three zincs more peripherally located in the active site. As noted for catalytic domains of other phosphoethanolamine transferases, binding sites for the lipid A and phosphatidylethanolamine substrates are not apparent in the cMCR-1 structure, suggesting that they are present in the membrane domain.« less
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High Incidence of Escherichia coli Strains Coharboring mcr-1 and blaNDM from Chickens.
Liu, Bao-Tao; Song, Feng-Jing; Zou, Ming; Zhang, Qi-Di; Shan, Hu
2017-03-01
This study investigated the characteristics of Escherichia coli isolates carrying mcr-1-bla NDM from a chicken farm in China. Of the 78 E. coli isolates, 21 clonally unrelated isolates carried mcr-1-bla NDM Diverse IncI2 plasmids disseminated mcr-1 , while the dissemination of bla NDM was mediated by diverse IncB/O plasmids. More striking was the colocalization of resistance genes mcr-1 and bla NDM-4 in an IncHI2/ST3 plasmid, which might pose a great challenge for public health. Copyright © 2017 American Society for Microbiology.
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Emergence of colistin-resistant Escherichia coli clinical isolates harboring mcr-1 in Vietnam.
Tada, Tatsuya; Nhung, Pham Hong; Shimada, Kayo; Tsuchiya, Mitsuhiro; Phuong, Doan Mai; Anh, Nguyen Quoc; Ohmagari, Norio; Kirikae, Teruo
2017-10-01
The mcr-1 was first detected on a plasmid in colistin-resistant Escherichia coli from livestock and patients in China. We described here the emergence of colistin-resistant E. coli clinical isolates harboring mcr-1 on the chromosomes in Vietnam. To our knowledge, this is the first report of hospital-acquired E. coli isolates harboring mcr-1 in a medical setting in Vietnam. Copyright © 2017. Published by Elsevier Ltd.
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Locally Acquired mcr-1 in Escherichia coli, Australia, 2011 and 2013.
Ellem, Justin A; Ginn, Andrew N; Chen, Sharon C-A; Ferguson, John; Partridge, Sally R; Iredell, Jonathan R
2017-07-01
We identified discrete importation events of the mcr-1 gene on incompatibility group IncI2 plasmids in Escherichia coli isolated from patients in New South Wales, Australia, in 2011 and 2013. mcr-1 is present in a small minority of colistin-resistant Enterobacteriaceae and appears not to be established locally.
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Human Capital Development in the Cayman Islands: the Perception of Local Tertiary Education
ERIC Educational Resources Information Center
Bruce, Caula Andrea
2017-01-01
The remarkable economic success of the Cayman Islands is primarily driven by its large expatriate population. Expatriates make up over one-third of the total population of the Islands and half of the labor force. This has led some Caymanians to demand more opportunities for local individuals. However in April 2014, one of the two local newspapers…
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Yassin, Afrah Kamal; Zhang, Jilei; Wang, Jiawei; Chen, Li; Kelly, Patrick; Butaye, Patrick; Lu, Guangwu; Gong, Jiansen; Li, Min; Wei, Lanjing; Wang, Yaoyao; Qi, Kezong; Han, Xiangan; Price, Stuart; Hathcock, Terri; Wang, Chengming
2017-12-29
Antimicrobial resistance to colistin has emerged worldwide threatening the efficacy of one of the last-resort antimicrobials used for the treatment of multidrug-resistant Enterobacteriaceae infection in humans. In this study, we investigated the presence of colistin resistance genes (mcr-1, mcr-2, mcr-3) in Escherichia coli strains isolated from poultry and livestock collected between 2004 and 2012 in China. Furthermore, we studied the maintenance and transfer of the mcr-1 gene in E. coli after serial passages. Overall, 2.7% (17/624) of the E. coli isolates were positive for the mcr-1 gene while none were positive for the mcr-2 and mcr-3 genes. The prevalences of mcr-1 were similar in E. coli isolates from chickens (3.2%; 13/404), pigs (0.9%; 1/113) and ducks (6.8%; 3/44) but were absent in isolates from cattle (0/63). The mcr-1 gene was maintained in the E. coli after six passages (equivalent to 60 generations). In vitro transfer of mcr-1 was evident even without colistin selection. Our data indicate the presence of mcr-1 in extraintestinal E. coli from food-producing animals in China, and suggest that high numbers of the mcr-1-positive bacteria in poultry and livestock do not appear to be readily lost after withdrawal of colistin as a food additive. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
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Chromosomally Encoded mcr-5 in Colistin non-susceptible Pseudomonas aeruginosa.
Snesrud, Erik; Maybank, Rosslyn; Kwak, Yoon I; Jones, Anthony R; Hinkle, Mary K; Mc Gann, Patrick
2018-05-29
Whole genome sequencing (WGS) of historical Pseudomonas aeruginosa clinical isolates identified a chromosomal copy of mcr-5 within a Tn 3 -like transposon in P. aeruginosa MRSN 12280. The isolate was non-susceptible to colistin by broth microdilution and genome analysis revealed no mutations known to confer colistin resistance. To the best of our knowledge, this is the first report of mcr in colistin non-susceptible P. aeruginosa .
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Duggett, Nicholas A; Sayers, Ellie; AbuOun, Manal; Ellis, Richard J; Nunez-Garcia, Javier; Randall, Luke; Horton, Robert; Rogers, Jon; Martelli, Francesca; Smith, Richard P; Brena, Camilla; Williamson, Susanna; Kirchner, Miranda; Davies, Robert; Crook, Derrick; Evans, Sarah; Teale, Chris; Anjum, Muna F
2017-03-01
To determine the occurrence of mcr-1 -harbouring Escherichia coli in archived pig material originating in Great Britain (GB) from 2013 to 2015 and characterize mcr-1 plasmids. Enrichment and selective culture of 387 archived porcine caecal contents and recovery from archive of 1109 E. coli isolates to identify colistin-resistant bacteria by testing for the presence of mcr-1 by PCR and RT-PCR. mcr-1 -harbouring E. coli were characterized by WGS and compared with other available mcr-1 WGS. Using selective isolation following enrichment, the occurrence of mcr-1 E. coli in caeca from healthy pigs at slaughter from unique farms in GB was 0.6% (95% CI 0%-1.5%) in 2015. mcr-1 E. coli were also detected in isolates from two porcine veterinary diagnostic submissions in 2015. All isolates prior to 2015 were negative. WGS analysis of the four mcr-1 -positive E. coli indicated no other antimicrobial resistance (AMR) genes were linked to mcr-1 -plasmid-bearing contigs, despite all harbouring multiple AMR genes. The sequence similarity between mcr-1 -plasmid-bearing contigs identified and those found in GB, Chinese and South African human isolates and Danish, French and Estonian livestock-associated isolates was 90%-99%. mcr-1- harbouring plasmids were diverse, implying transposable elements are involved in mcr-1 transmission in GB. The low number of mcr-1 -positive E. coli isolates identified suggested mcr-1 is currently uncommon in E. coli from pigs within GB. The high sequence similarity between mcr-1 plasmid draft genomes identified in pig E. coli and plasmids found in human and livestock-associated isolates globally requires further investigation to understand the full implications. © Crown copyright 2016.
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Sun, Lichang; He, Tao; Zhang, Lili; Pang, Maoda; Zhang, Qiaoyan; Zhou, Yan; Bao, Hongduo; Wang, Ran
2017-07-28
The mcr-1 gene is a new "superbug" gene discoverd in China in 2016 that makes bacteria highly resistant to the last-resort class of antibiotics. The mcr-1 gene raised serious concern about its possible global dissemination and spread. Here, we report a potential anti-resistant strategy using the CRISPR/Cas9-mediated approach that can efficiently induce mcr-1 gene knockout in Escherichia coli . Our findings suggested that using the CRISPR/Cas9 system to knock out the resistance gene mcr-1 might be a potential anti-resistant strategy. Bovine myeloid antimicrobial peptide-27 could help deliver plasmid pCas::mcr targeting specific DNA sequences of the mcr-1 gene into microbial populations.
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Ramos-Ascherl, Zullaylee; Williams, Ernest H; Bunkley-Williams, Lucy; Tuttle, Lillian J; Sikkel, Paul C; Hixon, Mark A
2015-02-01
Recently, Pterois volitans, a Pacific species of lionfish, invaded the Atlantic Ocean, likely via the aquarium trade. We examined for internal and external parasites 188 individuals from 8 municipalities of Puerto Rico collected during 2009-2012, 91 individuals from Little Cayman, Cayman Islands, collected during the summers of 2010 and 2011, and 47 individuals from Lee Stocking Island, Bahamas, collected during the summer of 2009. In total, 27 parasite taxa were found, including 3 previously reported species from lionfish, the digenean Lecithochirium floridense, the leech Trachelobdella lubrica, and an Excorallana sp. isopod. We also report another 24 previously unreported parasite taxa from lionfish, including digeneans, monogeneans, cestodes, nematodes, isopods, a copepod, and an acanthocephalan. Among these parasites, several were previously unreported at their respective geographic origins: We report 5 new locality records from Puerto Rico, 9 from Cayman Islands, 5 from the Bahamas, 5 from the Caribbean, and 3 from the subtropical western Atlantic region. Three parasites are reported to associate with a fish host for the first time. The parasite faunas of P. volitans among our 3 study sites were quite different; most of the species infecting lionfish were generalists and/or species that infect carnivorous fishes. Although our study did not assess the impact of parasites on the fitness of invasive lionfish, it provides an important early step. Our results provide valuable comparative data for future studies at these and other sites throughout the lionfish's invaded range.
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Colistin-resistant Escherichia coli clinical isolate harbouring the mcr-1 gene in Ecuador.
Ortega-Paredes, D; Barba, P; Zurita, J
2016-10-01
Colistin resistance mediated by the mcr-1 gene has been reported worldwide, but to date not from the Andean region, South America. We report the first clinical isolate of Escherichia coli harbouring the mcr-1 gene in Ecuador. The strain was isolated from peritoneal fluid from a 14-year-old male with acute appendicitis, and subjected to molecular analysis. The minimum inhibitory concentration of colistin for the strain was 8 mg/ml and it was susceptible to carbapenems but resistant to tigecycline. The strain harboured mcr-1 and bla CTX-M-55 genes and was of sequence type 609. The recognition of an apparently commensal strain of E. coli harbouring mcr-1 serves as an alert to the presence in the region of this recently described resistance mechanism to one of the last line of drugs available for the treatment of multi-resistant Gram-negative infections.
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Colistin resistance mcr-1 gene bearing Escherichia coli from the United States
USDA-ARS?s Scientific Manuscript database
Transmissible colistin resistance in the form of an mcr-1 gene bearing plasmid has been recently reported in Enterobacteriaceae in several parts of the world. We report the completed genome sequence of an Escherichia coli isolated from swine in the US that carried the mcr-1 gene on an IncI2 type pl...
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Srijan, Apichai; Ruekit, Sirigade; Snesrud, Erik; Maybank, Rosslyn; Serichantalergs, Oralak; Kormanee, Rosarin; Sukhchat, Prawet; Sriyabhaya, Jossin; Hinkle, Mary; Crawford, John M.; McGann, Patrick; Swierczewski, Brett E.
2018-01-01
Multidrug-resistant Klebsiella pneumoniae strains are one of the most prevalent causes of nosocomial infections and pose an increasingly dangerous public health threat. The lack of remaining treatment options has resulted in the utilization of older drug classes, including colistin. As a drug of last resort, the discovery of plasmid-mediated colistin resistance by mcr-1 denotes the potential development of pandrug-resistant bacterial pathogens. To address the emergence of the mcr-1 gene, 118 gram-negative Enterobacteriaceae isolated from clinical samples collected at Queen Sirikit Naval Hospital in Chonburi, Thailand were screened for colistin resistance using automated antimicrobial susceptibility testing and conventional PCR screening. Two K. pneumoniae strains, QS17-0029 and QS17-0161, were positive for mcr-1, and both isolates were sequenced to closure using short- and long-read whole-genome sequencing. QS17-0029 carried 16 antibiotic resistance genes in addition to mcr-1, including 2 carbapenemases, blaNDM-1 and blaOXA-232. QS17-0161 carried 13 antibiotic resistance genes in addition to mcr-1, including the extended-spectrum β-lactamase blaCTX-M-55. Both isolates carried multiple plasmids, but mcr-1 was located alone on highly similar 33.9 Kb IncX4 plasmids in both isolates. The IncX4 plasmid shared considerable homology to other mcr-1-containing IncX4 plasmids. This is the first report of a clinical K. pneumoniae strain from Thailand carrying mcr-1 as well as the first strain to simultaneously carry mcr-1 and multiple carbapenemase genes (QS17-0029). The identification and characterization of these isolates serves to highlight the urgent need for continued surveillance and intervention in Southeast Asia, where extensively drug-resistant pathogens are being increasingly identified in hospital-associated infections. PMID:29688801
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Srijan, Apichai; Margulieux, Katie R; Ruekit, Sirigade; Snesrud, Erik; Maybank, Rosslyn; Serichantalergs, Oralak; Kormanee, Rosarin; Sukhchat, Prawet; Sriyabhaya, Jossin; Hinkle, Mary; Crawford, John M; McGann, Patrick; Swierczewski, Brett E
2018-05-01
Multidrug-resistant Klebsiella pneumoniae strains are one of the most prevalent causes of nosocomial infections and pose an increasingly dangerous public health threat. The lack of remaining treatment options has resulted in the utilization of older drug classes, including colistin. As a drug of last resort, the discovery of plasmid-mediated colistin resistance by mcr-1 denotes the potential development of pandrug-resistant bacterial pathogens. To address the emergence of the mcr-1 gene, 118 gram-negative Enterobacteriaceae isolated from clinical samples collected at Queen Sirikit Naval Hospital in Chonburi, Thailand were screened for colistin resistance using automated antimicrobial susceptibility testing and conventional PCR screening. Two K. pneumoniae strains, QS17-0029 and QS17-0161, were positive for mcr-1, and both isolates were sequenced to closure using short- and long-read whole-genome sequencing. QS17-0029 carried 16 antibiotic resistance genes in addition to mcr-1, including 2 carbapenemases, bla NDM-1 and bla OXA-232 . QS17-0161 carried 13 antibiotic resistance genes in addition to mcr-1, including the extended-spectrum β-lactamase bla CTX-M-55 . Both isolates carried multiple plasmids, but mcr-1 was located alone on highly similar 33.9 Kb IncX4 plasmids in both isolates. The IncX4 plasmid shared considerable homology to other mcr-1-containing IncX4 plasmids. This is the first report of a clinical K. pneumoniae strain from Thailand carrying mcr-1 as well as the first strain to simultaneously carry mcr-1 and multiple carbapenemase genes (QS17-0029). The identification and characterization of these isolates serves to highlight the urgent need for continued surveillance and intervention in Southeast Asia, where extensively drug-resistant pathogens are being increasingly identified in hospital-associated infections.
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MCR-1 and OXA-48 In Vivo Acquisition in KPC-Producing Escherichia coli after Colistin Treatment.
Beyrouthy, Racha; Robin, Frederic; Lessene, Aude; Lacombat, Igor; Dortet, Laurent; Naas, Thierry; Ponties, Valérie; Bonnet, Richard
2017-08-01
The spread of mcr-1 -encoding plasmids into carbapenem-resistant Enterobacteriaceae raises concerns about the emergence of untreatable bacteria. We report the acquisition of mcr-1 in a carbapenem-resistant Escherichia coli strain after a 3-week course of colistin in a patient repatriated to France from Portugal. Whole-genome sequencing revealed that the Klebsiella pneumoniae carbapenemase-producing E. coli strain acquired two plasmids, an IncL OXA-48-encoding plasmid and an IncX4 mcr-1 -encoding plasmid. This is the first report of mcr-1 in carbapenemase-encoding bacteria in France. Copyright © 2017 American Society for Microbiology.
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Coexistence of mcr-1 and blaNDM-1 in Escherichia coli from Venezuela.
Delgado-Blas, Jose F; Ovejero, Cristina M; Abadia-Patiño, Lorena; Gonzalez-Zorn, Bruno
2016-10-01
We studied the presence of the mobile colistin resistance gene mcr-1 in human, animal, and environmental Enterobacteriaceae samples from Cumana, Venezuela, that were collected in 2015. The mcr-1 gene was detected in 2/93 Escherichia coli isolates from swine (novel ST452) and human (ST19) samples that were resistant to colistin. Whole-genome sequencing and transformation experiments identified mcr-1 on an IncI2 plasmid. One of the isolates also bore the widely spread carbapenemase NDM-1. A One Health approach is necessary to further elucidate the flux of these high-risk genes. Copyright © 2016, American Society for Microbiology. All Rights Reserved.
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Lin, Jingxia; Wang, Xiuna; Deng, Xianbo; Feng, Youjun
2016-01-01
The emergence of the mobilized colistin resistance gene, representing a novel mechanism for bacterial drug resistance, challenges the last resort against the severe infections by Gram-negative bacteria with multi-drug resistances. Very recently, we showed the diversity in the mcr-1-carrying plasmid reservoirs from the gut microbiota. Here, we reported that a similar but more complex scenario is present in the healthy swine populations, Southern China, 2016. Amongst the 1026 pieces of Escherichia coli isolates from 3 different pig farms, 302 E. coli isolates were determined to be positive for the mcr-1 gene (30%, 302/1026). Multi-locus sequence typing assigned no less than 11 kinds of sequence types including one novel Sequence Type to these mcr-1-positive strains. PCR analyses combined with the direct DNA sequencing revealed unexpected complexity of the mcr-1-harbouring plasmids whose backbones are at least grouped into 6 types four of which are new. Transcriptional analyses showed that the mcr-1 promoter of different origins exhibits similar activity. It seems likely that complex dissemination of the diversified mcr-1-bearing plasmids occurs amongst the various ST E. coli inhabiting the healthy swine populations, in Southern China. PMID:27741523
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Ohsaki, Yusuke; Hayashi, Wataru; Saito, Satomi; Osaka, Shunsuke; Taniguchi, Yui; Koide, Shota; Kawamura, Kumiko; Nagano, Yukiko; Arakawa, Yoshichika; Nagano, Noriyuki
2017-09-25
Global spread of the plasmid-mediated colistin resistance gene, mcr-1 poses a challenge to public health because colistin is the last-line-of-defense against severe infections of multidrug-resistant Gram-negative bacteria. In Japan, a few studies have reported the prevalence of mcr-1 among food animal-derived Escherichia coli isolates, but the prevalence of mcr-1 in retail meats is not well known. We report here the first detection of mcr-1 in retail chicken meat. A total of 70 extended-spectrum beta-lactamase-producing E. coli isolates, recovered from retail chicken meats between August 2015 and June 2016, were screened for mcr-1. We found 1 CTX-M-1 beta-lactamase-producing E. coli isolate belonging to ST1684, phylogroup A. The mcr-1 gene was not located on an IncI1 plasmid encoding the bla CTX-M-1 gene. However, whole plasmid sequencing revealed that mcr-1 was located on an IncI2 plasmid. The sequences of the nikB-mcr-1-pap2-ydfA-topB region of the IncI2 plasmid in this study was almost identical to that of the previously described IncI2 plasmid, pECJS-61-63 present in E. coli isolated from pig feces in China, except for containing a synonymous mutation in the mcr-1 gene. Plasmid carrying the mcr-1 gene have not yet been identified in human isolates in Japan. Thus, strict monitoring or surveillance of colistin resistance among Gram-negative bacteria recovered from retail meat of food animals under colistin pressure, and humans, is crucial.
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Bulman, Zackery P; Chen, Liang; Walsh, Thomas J; Satlin, Michael J; Qian, Yuli; Bulitta, Jürgen B; Peloquin, Charles A; Holden, Patricia N; Nation, Roger L; Li, Jian; Kreiswirth, Barry N; Tsuji, Brian T
2017-07-25
The rapid increase of carbapenem resistance in Gram-negative bacteria has resurrected the importance of the polymyxin antibiotics. The recent discovery of plasmid-mediated polymyxin resistance ( mcr - 1 ) in carbapenem-resistant Enterobacteriaceae serves as an important indicator that the golden era of antibiotics is under serious threat. We assessed the bacterial killing of 15 different FDA-approved antibiotics alone and in combination with polymyxin B in time-killing experiments against Escherichia coli MCR1_NJ, the first reported isolate in the United States to coharbor mcr-1 and a New Delhi metallo-β-lactamase gene ( bla NDM-5 ). The most promising regimens were advanced to the hollow-fiber infection model (HFIM), where human pharmacokinetics for polymyxin B, aztreonam, and amikacin were simulated over 240 h. Exposure to polymyxin B monotherapy was accompanied by MCR1_NJ regrowth but not resistance amplification (polymyxin B MIC from 0 to 240 h [MIC 0h to MIC 240h ] of 4 mg/liter), whereas amikacin monotherapy caused regrowth and simultaneous resistance amplification (amikacin MIC 0h of 4 mg/liter versus MIC 240h of >64 mg/liter). No MCR1_NJ colonies were observed for any of the aztreonam-containing regimens after 72 h. However, HFIM cartridges for both aztreonam monotherapy and the polymyxin B-plus-aztreonam regimen were remarkably turbid, and the presence of long, filamentous MCR1_NJ cells was evident in scanning electron microscopy, suggestive of a nonreplicating persister (NRP) phenotype. In contrast, the 3-drug combination of polymyxin B, aztreonam, and amikacin provided complete eradication (>8-log 10 CFU/ml reduction) with suppression of resistance and prevention of NRP formation. This is the first comprehensive pharmacokinetic/pharmacodynamic study to evaluate triple-drug combinations for polymyxin- and carbapenem-resistant E. coli coproducing MCR-1 and NDM-5 and will aid in the preparation for a so-called "postantibiotic" era. IMPORTANCE A global
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Saavedra, Sandra Yamile; Diaz, Lorena; Wiesner, Magdalena; Correa, Adriana; Arévalo, Stefany Alejandra; Reyes, Jinnethe; Hidalgo, Andrea Melissa; de la Cadena, Elsa; Perenguez, Marcela; Montaño, Lucy Angeline; Ardila, Javier; Ríos, Rafael; Ovalle, María Victoria; Díaz, Paula; Porras, Paola; Villegas, Maria V; Arias, Cesar A; Beltrán, Mauricio; Duarte, Carolina
2017-12-01
Polymyxins are last-resort antimicrobial agents used to treat infections caused by carbapenem-resistant Enterobacteriaceae Due to the worldwide dissemination of polymyxin resistance in animal and human isolates, we aimed to characterize polymyxin resistance associated with the presence of mcr-1 in Enterobacteriaceae and nonfermenter Gram-negative bacilli, using isolates collected retrospectively in Colombia from 2002 to 2016. A total of 5,887 Gram-negative clinical isolates were studied, and 513 were found to be resistant to the polymyxins. Susceptibility to colistin was confirmed by broth microdilution for all mcr-1 -positive isolates, and these were further subjected to whole-genome sequencing (WGS). The localization of mcr-1 was confirmed by S1 pulsed-field gel electrophoresis (S1-PFGE) and CeuI-PFGE hybridization. Transferability was evaluated by mating assays. A total of 12 colistin-resistant isolates recovered after 2013 harbored mcr-1 , including 8 Escherichia coli , 3 Salmonella enterica serovar Typhimurium, and 1 Klebsiella pneumoniae isolate . E. coli isolates were unrelated by PFGE and belonged to 7 different sequence types (STs) and phylogroups. S Typhimurium and K. pneumoniae isolates belonged to ST34 and ST307, respectively. The mcr-1 gene was plasmid borne in all isolates but two E. coli isolates which harbored it on the chromosome. Conjugation of mcr-1 was successful in 8 of 10 isolates (8.2 × 10 -5 to 2.07 × 10 -1 cell per recipient). Plasmid sequences showed that the mcr-1 plasmids belonged to four different Inc groups (a new IncP-1 variant and the IncFII, IncHI1, and IncH families). Our results indicate that mcr-1 is circulating in clinical isolates of colistin-resistant Enterobacteriaceae in Colombia and is mainly harbored in transferable plasmids. Copyright © 2017 American Society for Microbiology.
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Diaz, Lorena; Wiesner, Magdalena; Correa, Adriana; Arévalo, Stefany Alejandra; Reyes, Jinnethe; Hidalgo, Andrea Melissa; de la Cadena, Elsa; Perenguez, Marcela; Montaño, Lucy Angeline; Ardila, Javier; Ríos, Rafael; Ovalle, María Victoria; Díaz, Paula; Porras, Paola; Villegas, Maria V.; Arias, Cesar A.; Beltrán, Mauricio
2017-01-01
ABSTRACT Polymyxins are last-resort antimicrobial agents used to treat infections caused by carbapenem-resistant Enterobacteriaceae. Due to the worldwide dissemination of polymyxin resistance in animal and human isolates, we aimed to characterize polymyxin resistance associated with the presence of mcr-1 in Enterobacteriaceae and nonfermenter Gram-negative bacilli, using isolates collected retrospectively in Colombia from 2002 to 2016. A total of 5,887 Gram-negative clinical isolates were studied, and 513 were found to be resistant to the polymyxins. Susceptibility to colistin was confirmed by broth microdilution for all mcr-1-positive isolates, and these were further subjected to whole-genome sequencing (WGS). The localization of mcr-1 was confirmed by S1 pulsed-field gel electrophoresis (S1-PFGE) and CeuI-PFGE hybridization. Transferability was evaluated by mating assays. A total of 12 colistin-resistant isolates recovered after 2013 harbored mcr-1, including 8 Escherichia coli, 3 Salmonella enterica serovar Typhimurium, and 1 Klebsiella pneumoniae isolate. E. coli isolates were unrelated by PFGE and belonged to 7 different sequence types (STs) and phylogroups. S. Typhimurium and K. pneumoniae isolates belonged to ST34 and ST307, respectively. The mcr-1 gene was plasmid borne in all isolates but two E. coli isolates which harbored it on the chromosome. Conjugation of mcr-1 was successful in 8 of 10 isolates (8.2 × 10−5 to 2.07 × 10−1 cell per recipient). Plasmid sequences showed that the mcr-1 plasmids belonged to four different Inc groups (a new IncP-1 variant and the IncFII, IncHI1, and IncH families). Our results indicate that mcr-1 is circulating in clinical isolates of colistin-resistant Enterobacteriaceae in Colombia and is mainly harbored in transferable plasmids. PMID:28893788
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von Wintersdorff, Christian J H; Wolffs, Petra F G; van Niekerk, Julius M; Beuken, Erik; van Alphen, Lieke B; Stobberingh, Ellen E; Oude Lashof, Astrid M L; Hoebe, Christian J P A; Savelkoul, Paul H M; Penders, John
2016-12-01
Recently, the first plasmid-mediated colistin-resistance gene, mcr-1, was reported. Colistin is increasingly used as an antibiotic of last resort for the treatment of infections caused by carbapenem-resistant bacteria, which have been rapidly disseminating worldwide in recent years. The reported carriage rate of mcr-1 in humans remains sporadic thus far, except for those reported in Chinese populations. We aimed to determine its presence in the faecal metagenomes of healthy Dutch travellers between 2010 and 2012. Faecal metagenomic DNA of pre- and post-travel samples from 122 healthy Dutch long-distance travellers was screened for the presence of mcr-1 using a TaqMan quantitative PCR assay, which was designed in this study. All positive samples were confirmed by sequencing of the amplicons. The mcr-1 gene was detected in 6 (4.9%, 95% CI = 2.1%-10.5%) of 122 healthy Dutch long-distance travellers after they had visited destinations in South(-east) Asia or southern Africa between 2011 and 2012. One of these participants was already found to be positive before travel. Our study highlights the potential of PCR-based targeted metagenomics as an unbiased and sensitive method to screen for the carriage of the mcr-1 gene and suggests that mcr-1 is widespread in various parts of the world. The observation that one participant was found to be positive before travel suggests that mcr-1 may already have disseminated to the microbiomes of Dutch residents at a low prevalence, warranting a more extensive investigation of its prevalence in the general population and possible sources. © The Author 2016. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
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McrEngine: A Scalable Checkpointing System Using Data-Aware Aggregation and Compression
Islam, Tanzima Zerin; Mohror, Kathryn; Bagchi, Saurabh; ...
2013-01-01
High performance computing (HPC) systems use checkpoint-restart to tolerate failures. Typically, applications store their states in checkpoints on a parallel file system (PFS). As applications scale up, checkpoint-restart incurs high overheads due to contention for PFS resources. The high overheads force large-scale applications to reduce checkpoint frequency, which means more compute time is lost in the event of failure. We alleviate this problem through a scalable checkpoint-restart system, mcrEngine. McrEngine aggregates checkpoints from multiple application processes with knowledge of the data semantics available through widely-used I/O libraries, e.g., HDF5 and netCDF, and compresses them. Our novel scheme improves compressibility ofmore » checkpoints up to 115% over simple concatenation and compression. Our evaluation with large-scale application checkpoints show that mcrEngine reduces checkpointing overhead by up to 87% and restart overhead by up to 62% over a baseline with no aggregation or compression.« less
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NASA Technical Reports Server (NTRS)
Springer, E.; Sachs, M. S.; Woese, C. R.; Boone, D. R.
1995-01-01
Representatives of the family Methanosarcinaceae were analyzed phylogenetically by comparing partial sequences of their methyl-coenzyme M reductase (mcrI) genes. A 490-bp fragment from the A subunit of the gene was selected, amplified by the PCR, cloned, and sequenced for each of 25 strains belonging to the Methanosarcinaceae. The sequences obtained were aligned with the corresponding portions of five previously published sequences, and all of the sequences were compared to determine phylogenetic distances by Fitch distance matrix methods. We prepared analogous trees based on 16S rRNA sequences; these trees corresponded closely to the mcrI trees, although the mcrI sequences of pairs of organisms had 3.01 +/- 0.541 times more changes than the respective pairs of 16S rRNA sequences, suggesting that the mcrI fragment evolved about three times more rapidly than the 16S rRNA gene. The qualitative similarity of the mcrI and 16S rRNA trees suggests that transfer of genetic information between dissimilar organisms has not significantly affected these sequences, although we found inconsistencies between some mcrI distances that we measured and and previously published DNA reassociation data. It is unlikely that multiple mcrI isogenes were present in the organisms that we examined, because we found no major discrepancies in multiple determinations of mcrI sequences from the same organism. Our primers for the PCR also match analogous sites in the previously published mcrII sequences, but all of the sequences that we obtained from members of the Methanosarcinaceae were more closely related to mcrI sequences than to mcrII sequences, suggesting that members of the Methanosarcinaceae do not have distinct mcrII genes.
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Randall, L P; Horton, R A; Lemma, F; Martelli, F; Duggett, N A D; Smith, R P; Kirchner, M J; Ellis, R J; Rogers, J P; Williamson, S M; Simons, R R L; Brena, C M; Evans, S J; Anjum, M F; Teale, C J
2018-05-09
In 2015, colistin-resistant Escherichia coli and Salmonella with the mcr-1 gene were isolated from a pig farm in Great Britain. Pigs were subsequently monitored over a ~20-month period for the occurrence of mcr-1-mediated colistin resistance and the risk of mcr-1 E. coli entering the food chain was assessed. Pig faeces and slurry were cultured for colistin-resistant E. coli and Salmonella, tested for the mcr-1 gene by PCR and selected isolates were further analysed. Seventy-eight per cent of faecal samples (n = 275) from pigs yielded mcr-1 E. coli after selective culture, but in positive samples only 0·2-1·3% of the total E. coli carried mcr-1. Twenty months after the initial sampling, faecal samples (n = 59) were negative for E. coli carrying mcr-1. The risk to public health from porcine E. coli carrying mcr-1 was assessed as very low. Twenty months after cessation of colistin use, E. coli carrying mcr-1 was not detected in pig faeces on a farm where it was previously present. The results suggest that cessation of colistin use may help over time to reduce or possibly eliminate mcr-1 E. coli on pig farms where it occurs. © 2018 Crown copyright. Journal of Applied Microbiology © 2018 The Society for Applied Microbiology.
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Isotope and trace element insights into heterogeneity of subridge mantle
NASA Astrophysics Data System (ADS)
Mallick, Soumen; Dick, Henry J. B.; Sachi-Kocher, Afi; Salters, Vincent J. M.
2014-06-01
Geochemical data for abyssal peridotites are used to determine the relationship to mid-ocean ridge basalts from several locations at ridge segments on the SW Indian Ridge (SWIR), the Mid-Cayman-Rise (MCR), and the Mid-Atlantic Ridge (MAR). Based on chemical and petrological criteria peridotites are categorized as being either dominantly impregnated with melt or being residual after recent melting. Those that are considered impregnated with melt also have isotopic compositions similar to the basalts indicating impregnation by an aggregate MORB melt. A SWIR and MCR residual peridotite Nd-isotopic compositions partly overlap the Nd-isotopic compositions of the basalts but extend to more radiogenic compositions. The differences between peridotite and basalt Nd-isotopic compositions can be explained by incorporating a low-solidus component with enriched isotopic signature in the subridge mantle: a component that is preferentially sampled by the basalts. At the MAR, peridotites and associated basalts have overlapping Nd-isotopic compositions, suggesting a more homogeneous MORB mantle. The combined chemistry and petrography indicates a complex history with several depletion and enrichment events. The MCR data indicate that a low-solidus component can be a ubiquitous component of the asthenosphere. Residual abyssal peridotites from limited geographic areas also show significant chemical variations that could be associated with initial mantle heterogeneities related to events predating the ridge-melting event. Sm-Nd model ages for possible earlier depletion events suggest these could be as old as 2.4 Ga. This article was corrected on 9 JULY 2014. See the end of the full text for details.
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Wiley, J.W.
1991-01-01
In the 1490s a minimum of 28 species of psittacines occurred in the West Indies. Today, only 43% (12) of the species survive. All macaws and most parakeet species have been lost. Although the surviving parrot fauna of the Greater Antilles, Cayman Islands, and Bahama Islands has fared somewhat better than that of the Lesser Antilles, every species has undergone extensive reductions of populations and all but two have undergone extensive reductions in range, mostly as a result of habitat loss, but also from persecution as agricultural pests, conflicts with exotic species, harvesting for pets, and natural disasters. The Cayman Brac Parrot Amazona leucocephala hesterna with its tiny population (less than 150 individuals in the wild) and range, and the Puerto Rican Parrot A. vittata, with about 22-23 birds in the wild and 56 individuals in captivity, must be considered on the verge of extinction and in need of (in the latter's case, continuing) aggressive programmes of research and management. Other populations declining in numbers and range include the Yellow-billed Amazona collaria, and Black-billed A. agilis Parrots of Jamaica, Hispaniolan Parakeet Aratinga chloroptera, Hispaniolan Parrot Amazona ventralis, Cuban Parrot A. leucocephala leucocephala and, most seriously, Cuban Parakeet Aratinga euops. The population of the Grand Cayman Parrot (Amazona leucocephala caymanensis), although numbering only about 1,000 birds, appears stable and the current conservation programme gives hope for the survival of the race. An active conservation and public education programme has begun for the Bahama Parrot A. l. bahamensis, which still occurs in good numbers on Great Inagua Island, but is threatened on Abaco Island. Recommendations for conservation of parrots and parakeets in the region include (1) instituting long-term programmes of research to determine distribution, status, and ecology of each species; (2) developing conservation programmes through education and management
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Jyoti, Shravana Kumar; Blacke, Camille; Patil, Pallavi; Amblihalli, Vibha P; Nicholson, Amanda
2018-01-01
The common tool for diagnosing prostate cancer is prostate-specific antigen (PSA), but the high sensitivity and low specificity of PSA testing are the problems in clinical practice. There are no proper guidelines to investigate the suspected prostate cancer in the Cayman Islands. We correlated PSA levels with the incidence of prostate cancers by tissue diagnosis and proposed logical protocol for prostate screening by using PSA test in this small population. A total of 165 Afro Caribbean individuals who had prostate biopsy done after the investigations for PSA levels from year 2005 to 2015 were studied retrospectively. The patients were divided into subgroups by baseline PSA levels as follows: <4, 4.1-10, 10.1-20, 20.1-50, 50.1-100, and >100 ng/mL and were correlated to the age and presence of cancer. Benign lesions had lower PSA levels compared to cancer which generally had higher values. Only three cases that had less than 4 ng/mg were turned out to be malignant. When PSA value was more than 100 ng/mL, all the cases were malignant. Between PSA values of 4-100 ng/mL, the probability of cancer diagnosis was 56.71% (76 cancers out of 134 in this range). Limitation of PSA testing has the risk of over diagnosis and the resultant negative biopsies owing to poor specificity. Whereas the cutoff limit for cancer diagnosis still remains 4 ng/mL from our study, most of the patients can be assured of benign lesion below this level and thus morbidity associated with the biopsy can be prevented. When the PSA value is greater than 100 ng, biopsy procedure was mandatory as there were 100% cancers above this level. On the background of vast literature linking PSA to prostate cancer and its difficulty in implementing in clinical practice, we studied literature of this conflicting and complex topic and tried to bring relevant protocols to the small population of Cayman Islands for the screening of prostate cancer. In this study, a total of 165 Afro Caribbean individuals who
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Li, Ruichao; Xie, Miaomiao; Lv, Jingzhang; Wai-Chi Chan, Edward; Chen, Sheng
2017-03-01
To investigate the genetic features of three plasmids recovered from an MCR-1 and ESBL-producing Escherichia coli strain, HYEC7, and characterize the transmission mechanism of mcr-1 . The genetic profiles of three plasmids were determined by PCR, S1-PFGE, Southern hybridization and WGS analysis. The ability of the mcr-1 -bearing plasmid to undergo conjugation was also assessed. The mcr-1 -bearing transposon Tn 6330 was characterized by PCR and DNA sequencing. Complete sequences of three plasmids were obtained. A non-conjugative phage P7-like plasmid, pHYEC7- mcr1 , was found to harbour the mcr-1 -bearing transposon Tn 6330 , which could be excised from the plasmid by generating a circular intermediate harbouring mcr-1 and the IS Apl1 element. The insertion of the circular intermediate into another plasmid, pHYEC7-IncHI2, could form pHNSHP45-2, the original IncHI2-type mcr-1 -carrying plasmid that was reported. The third plasmid, pHYEC7-110, harboured two replicons, IncX1 and IncFIB, and comprised multiple antimicrobial resistance mobile elements, some of which were shared by pHYEC7-IncHI2. The Tn 6330 element located in the phage-like plasmid pHYEC7- mcr1 could be excised from the plasmid and formed a circular intermediate that could be integrated into plasmids containing the IS Apl1 element. This phenomenon indicated that Tn 6330 is a key element responsible for widespread dissemination of mcr-1 among various types of plasmids and bacterial chromosomes. The dissemination rate of such an element may be further enhanced upon translocation into phage-like vectors, which may also be transmitted via transduction events. © The Author 2016. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
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Guenther, Sebastian; Falgenhauer, Linda; Semmler, Torsten; Imirzalioglu, Can; Chakraborty, Trinad; Roesler, Uwe; Roschanski, Nicole
2017-05-01
Pigs have been the focus of the worldwide spread of colistin resistance. However, there is little information on the transmission of mcr-1 -containing bacteria into the environment of pig farms. We therefore rescreened environmental Escherichia coli isolates from the surrounding farm areas of three previously mcr-1 -positive swine herds in Germany. Thirty-five mixed bacterial cultures obtained from boot swabs, flies, dog faeces and manure from three pig farms in Germany in 2011-12 were non-selectively recultivated and the presence of the mcr-1 gene was checked by real-time PCR. After separation, single E. coli colonies were subsequently isolated and the presence of mcr-1 was confirmed by PCR and sequencing. In addition, phenotypic antimicrobial resistance screening and WGS followed by phylogenetic analysis and resistance genotyping as well as plasmid typing were performed. Seven mcr-1 -positive E. coli strains originating from environmental boot swabs, dog faeces, stable flies and manure were found. The isolates belonged to five different STs (ST10, ST1011, ST1140, ST5281 and ST342) and harboured extensive additional resistance genes. Comparative plasmid analysis predominantly located mcr-1 on IncX4 plasmids, which are strongly related to a recently described plasmid of human clinical origin (pICBEC72Hmcr). WGS-based analysis of the environmental E. coli isolates of farm surroundings showed clear links to mcr-1 -harbouring E. coli recovered from pig production in Europe as well as from human clinical isolates worldwide, presenting another piece of the puzzle, which further complicates the rapidly evolving epidemiology of plasmid-mediated colistin-resistant E. coli strains. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
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Borowiak, Maria; Fischer, Jennie; Hammerl, Jens A; Hendriksen, Rene S; Szabo, Istvan; Malorny, Burkhard
2017-12-01
Plasmid-mediated mobilized colistin resistance is currently known to be caused by phosphoethanolamine transferases termed MCR-1, MCR-2, MCR-3 and MCR-4. However, this study focuses on the dissection of a novel resistance mechanism in mcr-1-, mcr-2- and mcr-3-negative d-tartrate fermenting Salmonella enterica subsp. enterica serovar Paratyphi B (Salmonella Paratyphi B dTa+) isolates with colistin MIC values >2 mg/L. A selected isolate from the strain collection of the German National Reference Laboratory for Salmonella was investigated by WGS and bioinformatical analysis to identify novel phosphoethanolamine transferase genes involved in colistin resistance. Subsequently PCR screening, S1-PFGE and DNA-DNA hybridization were performed to analyse the prevalence and location of the identified mcr-5 gene. Cloning and transformation experiments in Escherichia coli DH5α and Salmonella Paratyphi B dTa+ control strains were carried out and the activity of MCR-5 was determined in vitro by MIC testing. In this study, we identified a novel phosphoethanolamine transferase in 14 mcr-1-, mcr-2- and mcr-3-negative Salmonella Paratyphi B dTa+ isolates with colistin MIC values >2 mg/L that were received during 2011-13. The respective gene, further termed as mcr-5 (1644 bp), is part of a 7337 bp transposon of the Tn3 family and usually located on related multi-copy ColE-type plasmids. Interestingly, in one isolate an additional subclone with a chromosomal location of the mcr-5 transposon was observed. Our findings suggest that the transfer of colistin-resistance-mediating phosphoethanolamine transferase genes from bacterial chromosomes to mobile genetic elements has occurred in multiple independent events raising concern regarding their variety, prevalence and impact on public health. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
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Kluytmans-van den Bergh, Marjolein F; Huizinga, Pepijn; Bonten, Marc J; Bos, Martine; De Bruyne, Katrien; Friedrich, Alexander W; Rossen, John W; Savelkoul, Paul H; Kluytmans, Jan A
2016-01-01
Recently, the plasmid-mediated colistin resistance gene mcr-1 was found in Enterobacteriaceae from humans, pigs and retail meat in China. Several reports have documented global presence of the gene in Enterobacteriaceae from humans, food animals and food since. We screened several well-characterised strain collections of Enterobacteriaceae, obtained from retail chicken meat and hospitalised patients in the Netherlands between 2009 and 2015, for presence of colistin resistance and the mcr-1 gene. A total of 2,471 Enterobacteriaceae isolates, from surveys in retail chicken meat (196 isolates), prevalence surveys in hospitalised patients (1,247 isolates), clinical cultures (813 isolates) and outbreaks in healthcare settings (215 isolates), were analysed. The mcr-1 gene was identified in three (1.5%) of 196 extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli isolates from retail chicken meat samples in 2009 and 2014. Two isolates were obtained from the same batch of meat samples, most likely representing contamination from a common source. No mcr-1-positive isolates were identified among 2,275 human isolates tested. All mcr-1-positive isolates were colistin-resistant (minimum inhibitory concentration (MIC) > 2 mg/L). Our findings indicate that mcr-1-based colistin-resistance currently poses no threat to healthcare in the Netherlands. They indicate however that continued monitoring of colistin resistance and its underlying mechanisms in humans, livestock and food is needed.
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Wang, Yang; Zhang, Rongmin; Li, Jiyun; Wu, Zuowei; Yin, Wenjuan; Schwarz, Stefan; Tyrrell, Jonathan M; Zheng, Yongjun; Wang, Shaolin; Shen, Zhangqi; Liu, Zhihai; Liu, Jianye; Lei, Lei; Li, Mei; Zhang, Qidi; Wu, Congming; Zhang, Qijing; Wu, Yongning; Walsh, Timothy R; Shen, Jianzhong
2017-02-06
By 2030, the global population will be 8.5 billion, placing pressure on international poultry production, of which China is a key producer 1 . From April 2017, China will implement the withdrawal of colistin as a growth promoter, removing over 8,000 tonnes per year from the Chinese farming sector 2 . To understand the impact of banning colistin and the epidemiology of multi-drug-resistant (MDR) Escherichia coli (using bla NDM and mcr-1 as marker genes), we sampled poultry, dogs, sewage, wild birds and flies. Here, we show that mcr-1, but not bla NDM , is prevalent in hatcheries, but bla NDM quickly contaminates flocks through dogs, flies and wild birds. We also screened samples directly for resistance genes to understand the true breadth and depth of the environmental and animal resistome. Direct sample testing for bla NDM and mcr-1 in hatcheries, commercial farms, a slaughterhouse and supermarkets revealed considerably higher levels of positive samples than the bla NDM - and mcr-1-positive E. coli, indicating a substantial segment of unseen resistome-a phenomenon we have termed the 'phantom resistome'. Whole-genome sequencing identified common bla NDM -positive E. coli shared among farms, flies, dogs and farmers, providing direct evidence of carbapenem-resistant E. coli transmission and environmental contamination.
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Li, Bo; Chai, Zhixin; Yan, Xiaohui; Liu, Chunchen; Situ, Bo; Zhang, Ye; Pan, Weilun; Luo, Shihua; Liu, Jianhua; Zheng, Lei
2018-05-22
Antibiotic resistance associated with the mcr-1 gene of Gram-negative bacteria, which confers resistance to drugs of last resort and has the potential to spread via plasmids, is one of the most pressing issues facing global health today. Point-of-care testing for the mcr-1 gene is needed to aid in the identification of colistin resistance in the field and to control its horizontal transmission. Here, we report the successful development of an enzyme-free homogenous electrochemical strategy for sensitive detection of the antibiotic resistance gene mcr-1 using the hybridization chain reaction and mcr-1-specific toehold probe. The long double-stranded DNA polymer produced using this strategy could be detected by assessing the diffusion of methylene blue towards the surface of a screen-printed gold electrode. Under optimized conditions, a linear relationship was observed between the variation of peak current and the natural logarithm of the mcr-1 gene concentration in the range of 1 nM to 1 μM with a detection limit of 0.78 nM (S/N = 3). This enzyme-free, isothermal platform is a rapid, portable, disposable, and sensitive method for detection of plasmid-mediated colistin resistance.
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Morris, R L; Tale, V P; Mathai, P P; Zitomer, D H; Maki, J S
2016-02-01
Anaerobic treatment is a sustainable and economical technology for waste stabilization and production of methane as a renewable energy. However, the process is under-utilized due to operational challenges. Organic overload or toxicants can stress the microbial community that performs waste degradation, resulting in system failure. In addition, not all methanogenic microbial communities are equally capable of consistent, maximum biogas production. Opinion varies as to which parameters should be used to monitor the fitness of digester biomass. No standard molecular tools are currently in use to monitor and compare full-scale operations. It was hypothesized that determining the number of gene copies of mcrA, a methanogen-specific gene, would positively correlate with specific methanogenic activity (SMA) rates from biomass samples from six full-scale anaerobic digester systems. Positive correlations were observed between mcrA gene copy numbers and methane production rates against H2 : CO2 and propionate (R(2) = 0·67-0·70, P < 0·05) but not acetate (R(2) = 0·49, P > 0·05). Results from this study indicate that mcrA gene targeted qPCR can be used as an alternate tool to monitor and compare certain methanogen communities in anaerobic digesters. Using quantitative PCR (qPCR), we demonstrate that the abundance of mcrA, a gene specific to methane producing archaea, correlated with specific methanogenic activity (SMA) measurements when H2 and CO2 , or propionate were provided as substrates. However, mcrA abundance did not correlate with SMA with acetate. SMA values are often used as a fitness indicator of anaerobic biomass. Results from qPCR can be obtained within a day while SMA analysis requires days to weeks to complete. Therefore, qPCR for mcrA abundance is a sensitive and fast method to compare and monitor the fitness of certain anaerobic biomass. As a monitoring tool, qPCR of mcrA will help anaerobic digester operators optimize treatment and encourage
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NASA Astrophysics Data System (ADS)
McDermott, J. M.; Seewald, J.; German, C. R.; Sylva, S. P.
2013-12-01
The generation of organic compounds in vent fluids has been of interest since the discovery of seafloor hydrothermal systems, due to implications for the sustenance of present-day microbial populations and their potential role in the origin of life on early Earth. Possible sources of organic compounds in hydrothermal systems include microbial production, thermogenic degradation of organic material, and abiotic synthesis. Abiotic organic synthesis reactions may occur during active circulation of seawater-derived fluids through the oceanic crust or within olivine-hosted fluid inclusions containing carbon-rich magmatic volatiles. H2-rich end-member fluids at the Von Damm vent field on the Mid-Cayman Rise, where fluid temperatures reach 226°C, provide an exciting opportunity to examine the extent of abiotic carbon transformations in a highly reducing system. Our results indicate multiple sources of carbon compounds in vent fluids at Von Damm. An ultramafic-influenced hydrothermal system located on the Mount Dent oceanic core complex at 2350 m depth, Von Damm vent fluids contain H2, CH4, and C2+ hydrocarbons in high abundance relative to basalt-hosted vent fields, and in similar abundance to other ultramafic-hosted systems, such as Rainbow and Lost City. The CO2 content and isotopic composition in end-member fluids are virtually identical to bottom seawater, suggesting that seawater DIC is unchanged during hydrothermal circulation of seawater-derived fluids. Accordingly, end-member CH4 that is present in slightly greater abundance than CO2 cannot be generated from reduction of aqueous CO2 during hydrothermal circulation. We postulate that CH4 and C2+ hydrocarbons that are abundantly present in Von Damm vent fluids reflect leaching of fluids from carbon- and H2-rich fluid inclusions hosted in plutonic rocks. Geochemical modeling of carbon speciation in the Von Damm fluids suggests that the relative abundances of CH4, C2+ hydrocarbons, and CO2 are consistent with
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USDA-ARS?s Scientific Manuscript database
Transmissible colistin resistance conferred by mcr-1 gene bearing IncI2 plasmid has been recently reported in Esherichia coli in the US. We report the completed genome sequence of a second E. coli isolated from swine in the US that carried the mcr-1 gene on an IncI2 type plasmid....
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Matamoros, Sébastien; van Hattem, Jarne M; Arcilla, Maris S; Willemse, Niels; Melles, Damian C; Penders, John; Vinh, Trung Nguyen; Thi Hoa, Ngo; de Jong, Menno D; Schultsz, Constance
2017-11-10
To understand the dynamics behind the worldwide spread of the mcr-1 gene, we determined the population structure of Escherichia coli and of mobile genetic elements (MGEs) carrying the mcr-1 gene. After a systematic review of the literature we included 65 E. coli whole genome sequences (WGS), adding 6 recently sequenced travel related isolates, and 312 MLST profiles. We included 219 MGEs described in 7 Enterobacteriaceae species isolated from human, animal and environmental samples. Despite a high overall diversity, 2 lineages were observed in the E. coli population that may function as reservoirs of the mcr-1 gene, the largest of which was linked to ST10, a sequence type known for its ubiquity in human faecal samples and in food samples. No genotypic clustering by geographical origin or isolation source was observed. Amongst a total of 13 plasmid incompatibility types, the IncI2, IncX4 and IncHI2 plasmids accounted for more than 90% of MGEs carrying the mcr-1 gene. We observed significant geographical clustering with regional spread of IncHI2 plasmids in Europe and IncI2 in Asia. These findings point towards promiscuous spread of the mcr-1 gene by efficient horizontal gene transfer dominated by a limited number of plasmid incompatibility types.
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NASA Astrophysics Data System (ADS)
Cameron, K. C.; Sirovic, A.; Jaffe, J. S.; Semmens, B.; Pattengill-Semmens, C.; Gibb, J.
2016-02-01
Fish spawning aggregation (FSA) sites are extremely vulnerable to over-exploitation. Accurate understanding of the spatial and temporal use of such sites is necessary for effective species management. The size of FSAs can be on the order of kilometers and peak spawning often occurs at night, posing challenges to visual observation. Passive acoustics are an alternative method for dealing with these challenges. An array of passive acoustic recorders and GoPro cameras were deployed during Nassau grouper (Epinephelus striatus) spawning from February 7th to 12th, 2015 at a multispecies spawning aggregation site in Little Cayman, Cayman Islands. In addition to Nassau grouper, at least 10 other species are known to spawn at this location including tiger grouper (Mycteroperca tigris), red hind (Epinephelus guttatus), black grouper (Mycteroperca bonaci), and yellowfin grouper (Mycteroperca venenosa). During 5 days of continuous recordings, over 21,000 fish calls were detected. These calls were classified into 15 common types. Species identification and behavioral context of unknown common call types were determined by coupling video recordings collected during this time with call localizations. There are distinct temporal patterns in call production of different species. For example, red hind and yellowfin grouper call predominately at night with yellowfin call rates increasing after midnight, and black grouper call primarily during dusk and dawn. In addition, localization methods were used to reveal how the FSA area was divided among species. These findings facilitate a better understanding of the behavior of these important reef fish species allowing policymakers to more effectively manage and protect them.
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mcr-1 Colistin Resistance in ESBL-Producing Klebsiella pneumoniae, France
Maillet, Mylène; Pavese, Patricia; Francony, Gilles; Brion, Jean-Paul; Mallaret, Marie-Reine; Bonnet, Richard; Robin, Frédéric; Beyrouthy, Racha; Maurin, Max
2017-01-01
We report intestinal carriage of an extended-spectrum β-lactamase−producing Klebsiella pneumoniae strain with high-level resistance to colistin (MIC 24 mg/L) in a patient in France who had been hospitalized for fungal meningitis. The strain had the mcr-1 plasmid gene and an inactivated mgrB gene, which are associated with colistin resistance. PMID:28418313
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NASA Astrophysics Data System (ADS)
Corlett, Hilary; Jones, Brian
2007-02-01
Thalassia testudinum, the most common seagrass found in lagoons around Grand Cayman, influences sedimentation by baffling currents, binding sediment on the seafloor, and providing substrates for a diverse epiphytic biota. About 85% of the epiphytic biota is formed of at least 3 species of coralline algae, 72 species of foraminifera, and 61 species of diatoms. The rest of the biota is formed of sponges, gastropods, ostracods, coccoliths, dinoflagellates, brown algae, and worms. The epiphytes are organized in three communities that are part of an organized tripartite community succession. The basal diatom community is overlain by the coralline algae community, which is then overlain by a community composed of a variety of taxa. The coralline algae community, which is the most extensive, typically covers ˜ 75% of the leaf's surface. Potentially, the skeletons of these epiphytes can make a significant contribution to the fine-grained sediment budget of these lagoons. Surprisingly, only a few of the epiphytes were found in the lagoonal sediment. It appears, therefore, that the epiphytes are lost through skeletal dissolution or transported out of the lagoon following storms. Irrespective of the cause, the epiphytes do not form a significant part of the lagoon sediment in Grand Cayman.
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Prevalence of mcr-1 in U.S. food-animal cecal contents
USDA-ARS?s Scientific Manuscript database
A survey of 2003 cecal content samples from chickens, turkeys, cattle and swine at slaughter facilities in the United States was conducted to estimate the prevalence of mcr-1 gene conferring resistance to colistin in Enterobacteriaceae. Two samples from swine had Escherichia coli with IncI2 plasmids...
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Ufnar, Jennifer A; Ufnar, David F; Wang, Shiao Y; Ellender, R D
2007-08-01
The goal of this study was to evaluate methanogen diversity in animal hosts to develop a swine-specific archaeal molecular marker for fecal source tracking in surface waters. Phylogenetic analysis of swine mcrA sequences compared to mcrA sequences from the feces of five animals (cow, deer, sheep, horse, and chicken) and sewage showed four distinct swine clusters, with three swine-specific clades. From this analysis, six sequences were chosen for molecular marker development and initial testing. Only one mcrA sequence (P23-2) showed specificity for swine and therefore was used for environmental testing. PCR primers for the P23-2 clone mcrA sequence were developed and evaluated for swine specificity. The P23-2 primers amplified products in P23-2 plasmid DNA (100%), pig feces (84%), and swine waste lagoon surface water samples (100%) but did not amplify a product in 47 bacterial and archaeal stock cultures and 477 environmental bacterial isolates and sewage and water samples from a bovine waste lagoon and a polluted creek. Amplification was observed in only one sheep sample out of 260 human and nonswine animal fecal samples. Sequencing of PCR products from pig feces demonstrated 100% similarity to pig mcrA sequence from clone P23-2. The minimal amount of DNA required for the detection was 1 pg for P23-2 plasmid, 1 ng for pig feces, 50 ng for swine waste lagoon surface water, 1 ng for sow waste influent, and 10 ng for lagoon sludge samples. Lower detection limits of 10(-6) g of wet pig feces in 500 ml of phosphate-buffered saline and 10(-4) g of lagoon waste in estuarine water were established for the P23-2 marker. This study was the first to utilize methanogens for the development of a swine-specific fecal contamination marker.
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Ufnar, Jennifer A.; Ufnar, David F.; Wang, Shiao Y.; Ellender, R. D.
2007-01-01
The goal of this study was to evaluate methanogen diversity in animal hosts to develop a swine-specific archaeal molecular marker for fecal source tracking in surface waters. Phylogenetic analysis of swine mcrA sequences compared to mcrA sequences from the feces of five animals (cow, deer, sheep, horse, and chicken) and sewage showed four distinct swine clusters, with three swine-specific clades. From this analysis, six sequences were chosen for molecular marker development and initial testing. Only one mcrA sequence (P23-2) showed specificity for swine and therefore was used for environmental testing. PCR primers for the P23-2 clone mcrA sequence were developed and evaluated for swine specificity. The P23-2 primers amplified products in P23-2 plasmid DNA (100%), pig feces (84%), and swine waste lagoon surface water samples (100%) but did not amplify a product in 47 bacterial and archaeal stock cultures and 477 environmental bacterial isolates and sewage and water samples from a bovine waste lagoon and a polluted creek. Amplification was observed in only one sheep sample out of 260 human and nonswine animal fecal samples. Sequencing of PCR products from pig feces demonstrated 100% similarity to pig mcrA sequence from clone P23-2. The minimal amount of DNA required for the detection was 1 pg for P23-2 plasmid, 1 ng for pig feces, 50 ng for swine waste lagoon surface water, 1 ng for sow waste influent, and 10 ng for lagoon sludge samples. Lower detection limits of 10−6 g of wet pig feces in 500 ml of phosphate-buffered saline and 10−4 g of lagoon waste in estuarine water were established for the P23-2 marker. This study was the first to utilize methanogens for the development of a swine-specific fecal contamination marker. PMID:17586669
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Impact of food animal trade on the spread of mcr-1-mediated colistin resistance, Tunisia, July 2015.
Grami, Raoudha; Mansour, Wejdene; Mehri, Wahib; Bouallègue, Olfa; Boujaâfar, Noureddine; Madec, Jean-Yves; Haenni, Marisa
2016-01-01
We report a high prevalence of MCR-1 and CTX-M-1-producing Escherichia coli in three Tunisian chicken farms. Chickens were imported from France or derived from French imported chicks. The same IncHI2-type plasmid reported to carry those genes in cattle in France and in a food sample in Portugal was found in Tunisian chickens of French origin. This suggests a significant impact of food animal trade on the spread of mcr-1-mediated colistin resistance in Europe.
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NASA Astrophysics Data System (ADS)
Chatterjee, Shiladitya; Singh, Bhupinder; Diwan, Anubhav; Lee, Zheng Rong; Engelhard, Mark H.; Terry, Jeff; Tolley, H. Dennis; Gallagher, Neal B.; Linford, Matthew R.
2018-03-01
X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS) are much used analytical techniques that provide information about the outermost atomic and molecular layers of materials. In this work, we discuss the application of multivariate spectral techniques, including principal component analysis (PCA) and multivariate curve resolution (MCR), to the analysis of XPS and ToF-SIMS depth profiles. Multivariate analyses often provide insight into data sets that is not easily obtained in a univariate fashion. Pattern recognition entropy (PRE), which has its roots in Shannon's information theory, is also introduced. This approach is not the same as the mutual information/entropy approaches sometimes used in data processing. A discussion of the theory of each technique is presented. PCA, MCR, and PRE are applied to four different data sets obtained from: a ToF-SIMS depth profile through ca. 100 nm of plasma polymerized C3F6 on Si, a ToF-SIMS depth profile through ca. 100 nm of plasma polymerized PNIPAM (poly (N-isopropylacrylamide)) on Si, an XPS depth profile through a film of SiO2 on Si, and an XPS depth profile through a film of Ta2O5 on Ta. PCA, MCR, and PRE reveal the presence of interfaces in the films, and often indicate that the first few scans in the depth profiles are different from those that follow. PRE and backward difference PRE provide this information in a straightforward fashion. Rises in the PRE signals at interfaces suggest greater complexity to the corresponding spectra. Results from PCA, especially for the higher principal components, were sometimes difficult to understand. MCR analyses were generally more interpretable.
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Pathways and Distribution of Marine Debris Around a Remote Caribbean Island, Little Cayman
NASA Astrophysics Data System (ADS)
Camp, L.; Marsh, L.; O'Keefe, A.; Duran, J.; Wilcox, S. M.; James, R.; Cowan, E.
2011-12-01
Marine Debris is a major environmental concern that affects all levels of marine life. On remote beaches in the Caribbean, where human populations are minimal, marine debris is largely deposited by ocean currents. The ocean is estimated to be littered with over 6 million metric tons of trash per year with 90% coming from land sources, but little is known about the exact sources and pathways for the debris. In 2006, on Little Cayman Island, coastal debris was collected at two coastal areas where removal of debris had not occurred in at least 9 years and along 2000 meters squared. One site was located on the north side, while the other site was located on the south side of the island. Both sites were located in reef-protected coastal zones. These two sites were revisited in 2007, 2010, and 2011 to determine the volume, weight, and type of debris arriving annually and to assess the importance of different coastal processes in deposition. In 2011, eight turtle nesting beaches were added to the study and a total of 11,186 liters of debris was collected from 1600 meters of coastline. The island lies in a northeast southwest orientation. The south-side of the island is influenced largely by prevailing trade winds, currents and tropical storms, traveling across the Caribbean from the east. Currents, eddies, and Norwesters would presumably deposit debris on the north side of the island. Approximately five times the amount of debris is deposited on the south side of the island than on the north side of the island. From the total debris collected, 72.45% was plastic, 8.23% shoes, 6.37% ropes & nets , 5.13% glass, 4.37% styrofoam, and 3.44% contained other debris. The marine debris originated in 8 different countries, and it is estimated that there is collectively 223,721 liters (11,635 kg) covering the shores of the entire island. Remarkably, debris found on Little Cayman in 2011 was traced to the 2010 Haitian earthquake relief effort.
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NASA Astrophysics Data System (ADS)
Elling, R. P.; Stein, C. A.; Stein, S.; Kley, J.; Keller, G. R.; Wysession, M. E.
2017-12-01
Continental rifts evolve to seafloor spreading and are preserved in passive margins, or fail and remain as fossil features in continents. Rifts at different stages give insight into these evolutionary paths. Of particular interest is the evolution of volcanic passive margins, which are characterized by seaward dipping reflectors, volcanic rocks yielding magnetic anomalies landward of the oldest spreading anomalies, and are underlain by high-velocity lower crustal bodies. How and when these features form remains unclear. Insights are given by the Midcontinent Rift (MCR), which began to form during the 1.1 Ga rifting of Amazonia from Laurentia, but failed when seafloor spreading was established elsewhere. MCR volcanics are much thicker than other continental flood basalts, due to deposition in a narrow rift rather than a broad region, giving a rift's geometry but a LIP's magma volume. The MCR provides a snapshot of the deposition of a thick and highly magnetized volcanic section during rifting. Surface exposures and reflection seismic data near Lake Superior show a rift basin filled by inward-dipping flood basalt layers. Had the rift evolved to seafloor spreading, the basin would have split into two sets of volcanics with opposite-facing SDRs, each with a magnetic anomaly. Because the rift formed as a series of alternating half-grabens, structural asymmetries between conjugate margins would have naturally occurred had it gone to completion. Hence the MCR implies that many passive margin features form prior to seafloor spreading. Massive inversion of the MCR long after it failed has provided a much clearer picture of its structure compared to failed rifts with lesser degrees of inversion. Seismic imaging as well as gravity and magnetic modeling provide important insight into the effects of inversion on failed rifts. The MCR provides an end member for the evolution of actively extending rifts, characterized by upwelling mantle and negative gravity anomalies, to failed
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Liu, Bao-Tao; Song, Feng-Jing; Zou, Ming; Hao, Zhi-Hui; Shan, Hu
2017-02-01
We report the presence of mcr-1 in Escherichia coli and carbapenem-resistant Cronobacter sakazakii from the same diseased chicken. The mcr-1 gene linked with ISApl1 was located on two different IncI2 plasmids, including one multidrug plasmid in E. coli, whereas fosA3-bla NDM-9 was on an IncB/O plasmid in C. sakazakii The development of the fosA3-bla NDM-9 resistance region was mediated by IS26 The colocation of mcr-1 or bla NDM-9 with other resistance genes will accelerate the dissemination of the two genes. Copyright © 2017 American Society for Microbiology.
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Santana, Priscila Bessa; Junior, Rubens Ghilardi; Alves, Claudio Nahum; Silva, Jeronimo Lameira; McCulloch, John Anthony; Schneider, Maria Paula Cruz; da Costa da Silva, Artur
2012-01-01
Methanogenic archaeans are organisms of considerable ecological and biotechnological interest that produce methane through a restricted metabolic pathway, which culminates in the reaction catalyzed by the Methyl-coenzyme M reductase (Mcr) enzyme, and results in the release of methane. Using a metagenomic approach, the gene of the α subunit of mcr (mcrα) was isolated from sediment sample from an anoxic zone, rich in decomposing organic material, obtained from the Tucuruí hydroelectric dam reservoir in eastern Brazilian Amazonia. The partial nucleotide sequences obtained were 83 to 95% similar to those available in databases, indicating a low diversity of archaeans in the reservoir. Two orders were identified - the Methanomicrobiales, and a unique Operational Taxonomic Unit (OTU) forming a clade with the Methanosarcinales according to low bootstrap values. Homology modeling was used to determine the three-dimensional (3D) structures, for this the partial nucleotide sequence of the mcrα were isolated and translated on their partial amino acid sequences. The 3D structures of the archaean Mcrα observed in the present study varied little, and presented approximately 70% identity in comparison with the Mcrα of Methanopyrus klanderi. The results demonstrated that the community of methanogenic archaeans of the anoxic C1 region of the Tucurui reservoir is relatively homogeneous. PMID:22481885
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mcrA-Targeted Real-Time Quantitative PCR Method To Examine Methanogen Communities▿
Steinberg, Lisa M.; Regan, John M.
2009-01-01
Methanogens are of great importance in carbon cycling and alternative energy production, but quantitation with culture-based methods is time-consuming and biased against methanogen groups that are difficult to cultivate in a laboratory. For these reasons, methanogens are typically studied through culture-independent molecular techniques. We developed a SYBR green I quantitative PCR (qPCR) assay to quantify total numbers of methyl coenzyme M reductase α-subunit (mcrA) genes. TaqMan probes were also designed to target nine different phylogenetic groups of methanogens in qPCR assays. Total mcrA and mcrA levels of different methanogen phylogenetic groups were determined from six samples: four samples from anaerobic digesters used to treat either primarily cow or pig manure and two aliquots from an acidic peat sample stored at 4°C or 20°C. Only members of the Methanosaetaceae, Methanosarcina, Methanobacteriaceae, and Methanocorpusculaceae and Fen cluster were detected in the environmental samples. The three samples obtained from cow manure digesters were dominated by members of the genus Methanosarcina, whereas the sample from the pig manure digester contained detectable levels of only members of the Methanobacteriaceae. The acidic peat samples were dominated by both Methanosarcina spp. and members of the Fen cluster. In two of the manure digester samples only one methanogen group was detected, but in both of the acidic peat samples and two of the manure digester samples, multiple methanogen groups were detected. The TaqMan qPCR assays were successfully able to determine the environmental abundance of different phylogenetic groups of methanogens, including several groups with few or no cultivated members. PMID:19447957
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Wilkins, David; Lu, Xiao-Ying; Shen, Zhiyong; Chen, Jiapeng
2014-01-01
Methanogenic archaea play a key role in biogas-producing anaerobic digestion and yet remain poorly taxonomically characterized. This is in part due to the limitations of low-throughput Sanger sequencing of a single (16S rRNA) gene, which in the past may have undersampled methanogen diversity. In this study, archaeal communities from three sludge digesters in Hong Kong and one wastewater digester in China were examined using high-throughput pyrosequencing of the methyl coenzyme M reductase (mcrA) and 16S rRNA genes. Methanobacteriales, Methanomicrobiales, and Methanosarcinales were detected in each digester, indicating that both hydrogenotrophic and acetoclastic methanogenesis was occurring. Two sludge digesters had similar community structures, likely due to their similar design and feedstock. Taxonomic classification of the mcrA genes suggested that these digesters were dominated by acetoclastic methanogens, particularly Methanosarcinales, while the other digesters were dominated by hydrogenotrophic Methanomicrobiales. The proposed euryarchaeotal order Methanomassiliicoccales and the uncultured WSA2 group were detected with the 16S rRNA gene, and potential mcrA genes for these groups were identified. 16S rRNA gene sequencing also recovered several crenarchaeotal groups potentially involved in the initial anaerobic digestion processes. Overall, the two genes produced different taxonomic profiles for the digesters, while greater methanogen richness was detected using the mcrA gene, supporting the use of this functional gene as a complement to the 16S rRNA gene to better assess methanogen diversity. A significant positive correlation was detected between methane production and the abundance of mcrA transcripts in digesters treating sludge and wastewater samples, supporting the mcrA gene as a biomarker for methane yield. PMID:25381241
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NASA Astrophysics Data System (ADS)
Camp, E.; Manfrino, C.; Smith, D.; Suggett, D.
2013-05-01
There is growing evidence demonstrating that climate change, notably increased frequency and intensity of thermal anomalies combined with ocean acidification, will negatively impact the future growth and viability of many reef systems, including those in the Caribbean. One key question that remains unanswered is whether or not there are management options aimed at protecting coral species from these threats. Little Cayman (Cayman Islands) provides a rare opportunity to investigate global climate stressors without the confounding impact of local anthropogenic stressors. Our research has focused on two climate change issues: Firstly, we have identified species-specific coral bleaching susceptibility (and the influence of regulation upon this susceptibility) to thermal anomalies. Species level of vulnerability to thermal anomalies can decrease when grown under variable temperature. Environmental variability may be key in influencing the susceptibility of corals to stress. The second part of our research has therefore addressed the variability in inorganic carbon chemistry that naturally occurs where certain reef building corals exist. We have identified how the inorganic carbon chemistry varies naturally among habitats and thus how corals within these habitats are potentially adapted to future acidification. Spatial, diurnal, lunar and seasonal variability have been identified as important factors with pCO2 values of up to 700-800 μatm and pH values as low as 7.801 for lagoon habitats, showing that some species are already being exposed to typical pCO2 and pH levels expected for the oceans in ~50 years' time. Using an eco-physiological approach, we are exploring how some reef-building corals are able to acclimate to more variable chemistry compared to others and whether this natural capacity installs increased tolerance to future acidification. These eco-physiological studies provide important information that can be utilized in a management framework. The aim of
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A study to assess the usage of MCR footwear in West Bengal, India.
Lal, Vivek; Sarkar, Debajit; Das, Sukumar; Mahato, Mukunda; Srinivas, Govindrajulu
2015-09-01
The routine use of appropriate footwear is an important intervention to prevent disability in leprosy. We conducted a study to assess utilisation of MCR footwear and observe the condition of footwear. Fifty-six persons affected by leprosy who had been provided MCR footwear in the preceding 3 years were paid home visit and administered a semi-structured interview schedule. Although a total of 30 participants reported using special footwear currently, only 10 reported usage during participation in social events. On observation, 16 pairs were found to be in an unusable condition owing to foot deformity and another 14 pairs in poor condition. In order to ensure greater utilisation of special footwear, the National Programme may seek local solutions through engagement of cobblers and shoemakers with appropriate training in customisation. Persons affected by leprosy should be empowered to appreciate the benefits of special footwear and to take care of themselves, including taking responsibility for using their footwear.
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Garza-Ramos, Ulises; Tamayo-Legorreta, Elsa; Arellano-Quintanilla, Doris María; Rodriguez-Medina, Nadia; Silva-Sanchez, Jesús; Catalan-Najera, Juan; Rocha-Martínez, Marisol Karina; Bravo-Díaz, María Asunción
2018-01-01
ABSTRACT A colistin-resistant mcr-1-carrying Escherichia coli strain, RC2-007, was isolated from a swine farm in Mexico. This extraintestinal and uropathogenic strain of E. coli belongs to serotype O89:H9 and sequence type 744. Assembly and annotation resulted in a 4.9-Mb draft genome that revealed the presence of plasmid-mediated mcr-1-ISApI1 genes as part of a prophage. PMID:29519827
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Marques, Aline S; Bedia, Carmen; Lima, Kássio M G; Tauler, Romà
2016-08-01
Cyanobacteria are a group of photosynthetic, nitrogen-fixing bacteria present in a wide variety of habitats such as freshwater, marine, and terrestrial ecosystems. In this work, the effects of As(III), a major toxic environmental pollutant, on the lipidomic profiles of two cyanobacteria species (Anabaena and Planktothrix agardhii) were assessed by means of a recently proposed method based on the concept of regions of interest (ROI) in liquid chromatography mass spectroscopy (LC-MS) together with multivariate curve resolution alternating least squares (MCR-ALS). Cyanobacteria were exposed to two concentrations of As(III) for a week, and lipid extracts were analyzed by ultrahigh-performance liquid chromatography/time-of-flight mass spectrometry in full scan mode. The data obtained were compressed by means of the ROI strategy, and the resulting LC-MS data sets were analyzed by the MCR-ALS method. Comparison of profile peak areas resolved by MCR-ALS in control and exposed samples allowed the discrimination of lipids whose concentrations were changed due to As(III) treatment. The tentative identification of these lipids revealed an important reduction of the levels of some galactolipids such as monogalactosyldiacylglycerol, the pigment chlorophyll a and its degradation product, pheophytin a, as well as carotene compounds such as 3-hydroxycarotene and carotene-3,3'-dione, all of these compounds being essential in the photosynthetic process. These results suggested that As(III) induced important changes in the composition of lipids of cyanobacteria, which were able to compromise their energy production processes. Graphical abstract Steps of the proposed LC-MS + MCR-ALS procedure.
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Bi, Zhenwang; Berglund, Björn; Sun, Qiang; Nilsson, Maud; Chen, Baoli; Tärnberg, Maria; Ding, Lilu; Stålsby Lundborg, Cecilia; Bi, Zhenqiang; Tomson, Göran; Yao, Jingjing; Gu, Zhanying; Yin, Xiao; Kou, Zengqiang; Nilsson, Lennart E
2017-04-01
Since its initial discovery in China in 2015, the plasmid-mediated colistin resistance gene mcr-1 has been reported in Escherichia coli isolated from clinical samples, animals and meat worldwide. In this study, 706 extended-spectrum β-lactamase (ESBL)-producing E. coli from 411 persons were detected in a collection of faecal samples from 1000 rural residents in three counties in Shandong Province, China. These isolates were screened for mcr-1 and phenotypic colistin resistance. The gene was found in 3.5% of the isolates (from 4.9% of persons) from all three counties. All isolates with phenotypic colistin resistance carried mcr-1. These data indicate that commensal carriage of ESBL-producing E. coli with mcr-1 among persons in rural China was already present in 2012 and that mcr-1 was the most important colistin resistance mechanism. Interventions are necessary to minimise further dissemination of mcr-1, which would limit the future usefulness of colistin as a last-resort antibiotic. Copyright © 2017 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.
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De Brouwere, Katleen; Cornelis, Christa; Arvanitis, Athanasios; Brown, Terry; Crump, Derrick; Harrison, Paul; Jantunen, Matti; Price, Paul; Torfs, Rudi
2014-05-01
The maximum cumulative ratio (MCR) method allows the categorisation of mixtures according to whether the mixture is of concern for toxicity and if so whether this is driven by one substance or multiple substances. The aim of the present study was to explore, by application of the MCR approach, whether health risks due to indoor air pollution are dominated by one substance or are due to concurrent exposure to various substances. Analysis was undertaken on monitoring data of four European indoor studies (giving five datasets), involving 1800 records of indoor air or personal exposure. Application of the MCR methodology requires knowledge of the concentrations of chemicals in a mixture together with health-based reference values for those chemicals. For this evaluation, single substance health-based reference values (RVs) were selected through a structured review process. The MCR analysis found high variability in the proportion of samples of concern for mixture toxicity. The fraction of samples in these groups of concern varied from 2% (Flemish schools) to 77% (EXPOLIS, Basel, indoor), the variation being due not only to the variation in indoor air contaminant levels across the studies but also to other factors such as differences in number and type of substances monitored, analytical performance, and choice of RVs. However, in 4 out of the 5 datasets, a considerable proportion of cases were found where a chemical-by-chemical approach failed to identify the need for the investigation of combined risk assessment. Although the MCR methodology applied in the current study provides no consideration of commonality of endpoints, it provides a tool for discrimination between those mixtures requiring further combined risk assessment and those for which a single-substance assessment is sufficient. Copyright © 2014 Elsevier B.V. All rights reserved.
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Barrier layer for a MCrAlY basecoat superalloy combination
Sabol, Stephen M.; Goedjen, John G.; Vance, Steven J.
2001-01-01
A turbine component contains a substrate (22) such as a superalloy, a basecoat (24) of the type MCrAlY, and a continuous barrier layer (28) between the substrate and basecoat, where the barrier layer (28) is made of an alloy of (Re, Ta, Ru, Os)X, where X can be Ni, Co or their mixture, where the barrier layer is at least 2 micrometers thick and substantially prevents materials from both the basecoat and substrate from migrating through it.
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Garza-Ramos, Ulises; Tamayo-Legorreta, Elsa; Arellano-Quintanilla, Doris María; Rodriguez-Medina, Nadia; Silva-Sanchez, Jesús; Catalan-Najera, Juan; Rocha-Martínez, Marisol Karina; Bravo-Díaz, María Asunción; Alpuche-Aranda, Celia
2018-03-08
A colistin-resistant mcr-1 -carrying Escherichia coli strain, RC2-007, was isolated from a swine farm in Mexico. This extraintestinal and uropathogenic strain of E. coli belongs to serotype O89:H9 and sequence type 744. Assembly and annotation resulted in a 4.9-Mb draft genome that revealed the presence of plasmid-mediated mcr-1 -IS ApI1 genes as part of a prophage. Copyright © 2018 Garza-Ramos et al.
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The PhoP-Dependent ncRNA Mcr7 Modulates the TAT Secretion System in Mycobacterium tuberculosis
Benjak, Andrej; Uplekar, Swapna; Rougemont, Jacques; Guilhot, Christophe; Malaga, Wladimir; Martín, Carlos; Cole, Stewart T.
2014-01-01
The PhoPR two-component system is essential for virulence in Mycobacterium tuberculosis where it controls expression of approximately 2% of the genes, including those for the ESX-1 secretion apparatus, a major virulence determinant. Mutations in phoP lead to compromised production of pathogen-specific cell wall components and attenuation both ex vivo and in vivo. Using antibodies against the native protein in ChIP-seq experiments (chromatin immunoprecipitation followed by high-throughput sequencing) we demonstrated that PhoP binds to at least 35 loci on the M. tuberculosis genome. The PhoP regulon comprises several transcriptional regulators as well as genes for polyketide synthases and PE/PPE proteins. Integration of ChIP-seq results with high-resolution transcriptomic analysis (RNA-seq) revealed that PhoP controls 30 genes directly, whilst regulatory cascades are responsible for signal amplification and downstream effects through proteins like EspR, which controls Esx1 function, via regulation of the espACD operon. The most prominent site of PhoP regulation was located in the intergenic region between rv2395 and PE_PGRS41, where the mcr7 gene codes for a small non-coding RNA (ncRNA). Northern blot experiments confirmed the absence of Mcr7 in an M. tuberculosis phoP mutant as well as low-level expression of the ncRNA in M. tuberculosis complex members other than M. tuberculosis. By means of genetic and proteomic analyses we demonstrated that Mcr7 modulates translation of the tatC mRNA thereby impacting the activity of the Twin Arginine Translocation (Tat) protein secretion apparatus. As a result, secretion of the immunodominant Ag85 complex and the beta-lactamase BlaC is affected, among others. Mcr7, the first ncRNA of M. tuberculosis whose function has been established, therefore represents a missing link between the PhoPR two-component system and the downstream functions necessary for successful infection of the host. PMID:24874799
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Kumar, Keshav
2017-11-01
Multivariate curve resolution alternating least square (MCR-ALS) analysis is the most commonly used curve resolution technique. The MCR-ALS model is fitted using the alternate least square (ALS) algorithm that needs initialisation of either contribution profiles or spectral profiles of each of the factor. The contribution profiles can be initialised using the evolve factor analysis; however, in principle, this approach requires that data must belong to the sequential process. The initialisation of the spectral profiles are usually carried out using the pure variable approach such as SIMPLISMA algorithm, this approach demands that each factor must have the pure variables in the data sets. Despite these limitations, the existing approaches have been quite a successful for initiating the MCR-ALS analysis. However, the present work proposes an alternate approach for the initialisation of the spectral variables by generating the random variables in the limits spanned by the maxima and minima of each spectral variable of the data set. The proposed approach does not require that there must be pure variables for each component of the multicomponent system or the concentration direction must follow the sequential process. The proposed approach is successfully validated using the excitation-emission matrix fluorescence data sets acquired for certain fluorophores with significant spectral overlap. The calculated contribution and spectral profiles of these fluorophores are found to correlate well with the experimental results. In summary, the present work proposes an alternate way to initiate the MCR-ALS analysis.
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Smith, Joseph P; Smith, Frank C; Booksh, Karl S
2018-03-01
Lunar meteorites provide a more random sampling of the surface of the Moon than do the returned lunar samples, and they provide valuable information to help estimate the chemical composition of the lunar crust, the lunar mantle, and the bulk Moon. As of July 2014, ∼96 lunar meteorites had been documented and ten of these are unbrecciated mare basalts. Using Raman imaging with multivariate curve resolution-alternating least squares (MCR-ALS), we investigated portions of polished thin sections of paired, unbrecciated, mare-basalt lunar meteorites that had been collected from the LaPaz Icefield (LAP) of Antarctica-LAP 02205 and LAP 04841. Polarized light microscopy displays that both meteorites are heterogeneous and consist of polydispersed sized and shaped particles of varying chemical composition. For two distinct probed areas within each meteorite, the individual chemical species and associated chemical maps were elucidated using MCR-ALS applied to Raman hyperspectral images. For LAP 02205, spatially and spectrally resolved clinopyroxene, ilmenite, substrate-adhesive epoxy, and diamond polish were observed within the probed areas. Similarly, for LAP 04841, spatially resolved chemical images with corresponding resolved Raman spectra of clinopyroxene, troilite, a high-temperature polymorph of anorthite, substrate-adhesive epoxy, and diamond polish were generated. In both LAP 02205 and LAP 04841, substrate-adhesive epoxy and diamond polish were more readily observed within fractures/veinlet features. Spectrally diverse clinopyroxenes were resolved in LAP 04841. Factors that allow these resolved clinopyroxenes to be differentiated include crystal orientation, spatially distinct chemical zoning of pyroxene crystals, and/or chemical and molecular composition. The minerals identified using this analytical methodology-clinopyroxene, anorthite, ilmenite, and troilite-are consistent with the results of previous studies of the two meteorites using electron microprobe
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Investigation of First Identified mcr-1 Gene in an Isolate from a U.S. Patient - Pennsylvania, 2016.
Kline, Kelly E; Shover, Jordan; Kallen, Alexander J; Lonsway, David R; Watkins, Sharon; Miller, Jeffrey R
2016-09-16
In 2015, scientists reported the emergence of the plasmid-encoded mcr-1 gene conferring bacterial resistance to the antibiotic colistin (1), signaling potential emergence of a pandrug-resistant bacterium. In May 2016, mcr-1-positive Escherichia coli was first isolated from a specimen from a U.S. patient (2) when a Pennsylvania woman was evaluated for a urinary tract infection. The urine culture and subsequent testing identified the gene in an extended-spectrum beta-lactamase (ESBL)-producing E. coli with reduced susceptibility to colistin. The patient had no international travel for approximately 1 year, no livestock exposure, and a limited role in meal preparation with store-bought groceries; however, she had multiple and repeated admissions to four medical facilities during 2016.
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Ardila, Jorge Armando; Funari, Cristiano Soleo; Andrade, André Marques; Cavalheiro, Alberto José; Carneiro, Renato Lajarim
2015-01-01
Bauhinia forficata Link. is recognised by the Brazilian Health Ministry as a treatment of hypoglycemia and diabetes. Analytical methods are useful to assess the plant identity due the similarities found in plants from Bauhinia spp. HPLC-UV/PDA in combination with chemometric tools is an alternative widely used and suitable for authentication of plant material, however, the shifts of retention times for similar compounds in different samples is a problem. To perform comparisons between the authentic medicinal plant (Bauhinia forficata Link.) and samples commercially available in drugstores claiming to be "Bauhinia spp. to treat diabetes" and to evaluate the performance of multivariate curve resolution - alternating least squares (MCR-ALS) associated to principal component analysis (PCA) when compared to pure PCA. HPLC-UV/PDA data obtained from extracts of leaves were evaluated employing a combination of MCR-ALS and PCA, which allowed the use of the full chromatographic and spectrometric information without the need of peak alignment procedures. The use of MCR-ALS/PCA showed better results than the conventional PCA using only one wavelength. Only two of nine commercial samples presented characteristics similar to the authentic Bauhinia forficata spp., considering the full HPLC-UV/PDA data. The combination of MCR-ALS and PCA is very useful when applied to a group of samples where a general alignment procedure could not be applied due to the different chromatographic profiles. This work also demonstrates the need of more strict control from the health authorities regarding herbal products available on the market. Copyright © 2015 John Wiley & Sons, Ltd.
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Early origins of the Caribbean plate from deep seismic profiles across the Nicaraguan Rise
NASA Astrophysics Data System (ADS)
Ott, B.; Mann, W. P.
2012-12-01
The offshore Nicaraguan Rise in the maritime zones of Honduras, Jamaica, Nicaragua and Colombia covers a combined area of 500,000 km2, and is one of the least known equatorial Cretaceous-Cenozoic carbonate regions remaining on Earth. The purpose of this study is to describe the Cretaceous to Recent tectonic and stratigraphic history of the deep water Nicaraguan Rise, and to better understand how various types of crustal blocks underlying the Eocene to Recent carbonate cover fused into a single, larger Caribbean plate known today from GPS studies. We interpreted 8700 km of modern, deep-penetration 2D seismic data kindly provided by the oil industry, tied to five wells that penetrated Cretaceous igneous basement. Based on these data, and integration with gravity, magnetic and existing crustal refraction data, we define four crustal provinces for the offshore Nicaraguan Rise: 1) Thicker (15-18 km) Late Cretaceous Caribbean ocean plateau (COP) with rough, top basement surface; 2) normal (6-8 km) Late Cretaceous COP with smooth top basement surface (B") and correlative outcrops in southern Haiti and Jamaica; 3) Precambrian-Paleozoic continental crust (20-22 km thick) with correlative outcrops in northern Central America; and 4) Cretaceous arc crust (>18 km thick) with correlative outcrops in Jamaica. These strongly contrasting basement belts strike northeastward to eastward, and were juxtaposed by latest Cretaceous-Paleogene northward and northwestward thrusting of Caribbean arc over continental crust in Central America, and the western Nicaraguan Rise (84 to 85 degrees west). A large Paleogene to recent, CCW rotation of the Caribbean plate along the Cayman trough faults and into its present day location explains why terranes in Central America and beneath the Nicaraguan Rise have their present, anomalous north-east strike. Continuing, present-day activity on some of these crustal block boundaries is a likely result of intraplate stresses imposed by the surrounding
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A New Look at the Bathymetric and Potential-Field Structure of the Cayman Trough via CaySEIS
NASA Astrophysics Data System (ADS)
Hayman, N. W.; Harding, J.; Van Avendonk, H. J.; Peirce, C.; Grevemeyer, I.; Dannowski, A.; Papenberg, C. A.
2015-12-01
The Cayman Trough (CT) has one of the world's deepest axial valleys, thinnest crust, end-member basalt composition, and slowest spreading rate. Accommodating motion between the North American and Caribbean plates, and the Gonave microplate, marine magnetic anomalies show that the Mid-Cayman Spreading Center (MCSC) has been spreading at ~15 mm/yr (F.R.) since 20 Ma, if not 49 Ma. At a little over 100 km in length, the MCSC is now recognized to host oceanic core complexes (OCCs), hydrothermal vents, and a seafloor of variably distributed lower crustal gabbros, upper mantle peridotite/serpentinite, and basaltic lavas. Though spreading rate appears to be relatively symmetric over geologic time, the structure of the CT is quite asymmetric, with a broad region of low gravity and somewhat lineated magnetic anomalies to the east, and gravity highs and irregular magnetic anomalies to the west. Until now it has been difficult to further assess the nature of the CT because of the sparse and generally old data from the region; the CT's claim on thinnest crust, for example, stems primarily from pre-1960's seismic data and inferences from satellite gravity. The CaySEIS active-source OBS-experiment on the R/V Meteor thus set out in April of 2015 to provide a more complete, deeper view of the CT. A serendipitous discovery during the expedition is that the off-axis seafloor is characterized by curvilinear ridges preserving what appear to be dismembered OCCs. Thus, a previously proposed model based on the oblique volcanic ridge to the south of the axial OCC, Mt. Dent, could also apply to the geologic history of the CT. This model, which we call "the magmatic cleaver", envisions how intrusions cut the OCC surfaces and raft the hanging-wall-dominated portion of the OCC to the east, and the footwall-dominated portion to the west. The "cleaver" appears to have been operating over at least the last 20 Ma, illustrating how melt flow in ultraslow-spread crust can create distinctive
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Hugelier, Siewert; Vitale, Raffaele; Ruckebusch, Cyril
2018-03-01
This article explores smoothing with edge-preserving properties as a spatial constraint for the resolution of hyperspectral images with multivariate curve resolution-alternating least squares (MCR-ALS). For each constrained component image (distribution map), irrelevant spatial details and noise are smoothed applying an L 1 - or L 0 -norm penalized least squares regression, highlighting in this way big changes in intensity of adjacent pixels. The feasibility of the constraint is demonstrated on three different case studies, in which the objects under investigation are spatially clearly defined, but have significant spectral overlap. This spectral overlap is detrimental for obtaining a good resolution and additional spatial information should be provided. The final results show that the spatial constraint enables better image (map) abstraction, artifact removal, and better interpretation of the results obtained, compared to a classical MCR-ALS analysis of hyperspectral images.
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mcr-1−Harboring Salmonella enterica Serovar Typhimurium Sequence Type 34 in Pigs, China
Yi, Linxian; Wang, Jing; Gao, Yanling; Liu, Yiyun; Doi, Yohei; Wu, Renjie; Zeng, Zhenling; Liang, Zisen
2017-01-01
We detected the mcr-1 gene in 21 (14.8%) Salmonella isolates from pigs at slaughter; 19 were serovar Typhimurium sequence type 34. The gene was located on IncHI2-like plasmids that also harbored IncF replicons and lacked a conjugative transfer region. These findings highlight the need to prevent further spread of colistin resistance in animals and humans. PMID:28098547
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Microbial trophic interactions and mcrA gene expression in monitoring of anaerobic digesters
Alvarado, Alejandra; Montañez-Hernández, Lilia E.; Palacio-Molina, Sandra L.; Oropeza-Navarro, Ricardo; Luévanos-Escareño, Miriam P.; Balagurusamy, Nagamani
2014-01-01
Anaerobic digestion (AD) is a biological process where different trophic groups of microorganisms break down biodegradable organic materials in the absence of oxygen. A wide range of AD technologies is being used to convert livestock manure, municipal and industrial wastewaters, and solid organic wastes into biogas. AD gains importance not only because of its relevance in waste treatment but also because of the recovery of carbon in the form of methane, which is a renewable energy and is used to generate electricity and heat. Despite the advances on the engineering and design of new bioreactors for AD, the microbiology component always poses challenges. Microbiology of AD processes is complicated as the efficiency of the process depends on the interactions of various trophic groups involved. Due to the complex interdependence of microbial activities for the functionality of the anaerobic bioreactors, the genetic expression of mcrA, which encodes a key enzyme in methane formation, is proposed as a parameter to monitor the process performance in real time. This review evaluates the current knowledge on microbial groups, their interactions, and their relationship to the performance of anaerobic biodigesters with a focus on using mcrA gene expression as a tool to monitor the process. PMID:25429286
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Microbial trophic interactions and mcrA gene expression in monitoring of anaerobic digesters.
Alvarado, Alejandra; Montañez-Hernández, Lilia E; Palacio-Molina, Sandra L; Oropeza-Navarro, Ricardo; Luévanos-Escareño, Miriam P; Balagurusamy, Nagamani
2014-01-01
Anaerobic digestion (AD) is a biological process where different trophic groups of microorganisms break down biodegradable organic materials in the absence of oxygen. A wide range of AD technologies is being used to convert livestock manure, municipal and industrial wastewaters, and solid organic wastes into biogas. AD gains importance not only because of its relevance in waste treatment but also because of the recovery of carbon in the form of methane, which is a renewable energy and is used to generate electricity and heat. Despite the advances on the engineering and design of new bioreactors for AD, the microbiology component always poses challenges. Microbiology of AD processes is complicated as the efficiency of the process depends on the interactions of various trophic groups involved. Due to the complex interdependence of microbial activities for the functionality of the anaerobic bioreactors, the genetic expression of mcrA, which encodes a key enzyme in methane formation, is proposed as a parameter to monitor the process performance in real time. This review evaluates the current knowledge on microbial groups, their interactions, and their relationship to the performance of anaerobic biodigesters with a focus on using mcrA gene expression as a tool to monitor the process.
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NASA Astrophysics Data System (ADS)
Jones, Brian
2009-07-01
Calcitic speleothems from a cave located on the north central coast of Grand Cayman commonly include corrosion surfaces that developed when calcite precipitation ceased and corrosion mediated by condensates became the operative process. Dissolution features associated with these surfaces, including etched crystal surfaces, microcavities, and solution-widened boundaries between crystals, are commonly occupied by microbes and microbial mats that have been replaced by calcium phosphate and/or coated with calcium phosphate. No mineralized microbes were found in the calcite crystals that form the speleothems. The morphology of the mineralized hyphae (eight morphotypes) and spores (nine morphotypes) are indicative of actinomycetes, a group of microbes that are ideally adapted to life in oligotrophic cave environs. Superb preservation of the delicate hyphae, aerial hyphae, and delicate ornamentation on the hyphae and spores indicate that the microbes underwent rapid mineralized while close to their original life positions. Although these actinomycetes were extremely susceptible to replacement by calcium phosphate, there is no evidence that they directly or indirectly controlled precipitation. Nevertheless, the association between the P-rich precipitates and microbes shows that the use of phosphorus as a proxy for seasonal climate changes in paleoclimate analyses must be treated with caution.
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NASA Astrophysics Data System (ADS)
Yamano, Hideaki; Tani, Kazumi; Harada, Yoshio; Teratani, Takema
2008-06-01
MCrAlY alloy bond coat is widely used in thermal barrier coating (TBC) systems to protect substrates from high-temperature oxidizing environments. However, failure of the ceramic topcoat can occur due to a thermally grown oxide (TGO) that grows at the interface between the bond coat and the topcoat. In this study, the effect of chromate treatment was investigated. Prior to topcoat deposition, a thin film of Cr2O3 was formed on the bond coat surface. High-temperature oxidation tests were carried out, and the oxidation rates were determined by inspection of cross sections. Similar oxidation tests were carried out using MCrAlY powder material assumed to be unmelted particles. As a result, the chromate-treated bond coat showed outstanding oxidation resistance. Calculations that take into account the oxidation of particles in the topcoat indicated the generation of internal stress to cause local fracture of the topcoat.
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Fornasaro, Stefano; Vicario, Annalisa; De Leo, Luigina; Bonifacio, Alois; Not, Tarcisio; Sergo, Valter
2018-05-14
Raman hyperspectral imaging is an emerging practice in biological and biomedical research for label free analysis of tissues and cells. Using this method, both spatial distribution and spectral information of analyzed samples can be obtained. The current study reports the first Raman microspectroscopic characterisation of colon tissues from patients with Coeliac Disease (CD). The aim was to assess if Raman imaging coupled with hyperspectral multivariate image analysis is capable of detecting the alterations in the biochemical composition of intestinal tissues associated with CD. The analytical approach was based on a multi-step methodology: duodenal biopsies from healthy and coeliac patients were measured and processed with Multivariate Curve Resolution Alternating Least Squares (MCR-ALS). Based on the distribution maps and the pure spectra of the image constituents obtained from MCR-ALS, interesting biochemical differences between healthy and coeliac patients has been derived. Noticeably, a reduced distribution of complex lipids in the pericryptic space, and a different distribution and abundance of proteins rich in beta-sheet structures was found in CD patients. The output of the MCR-ALS analysis was then used as a starting point for two clustering algorithms (k-means clustering and hierarchical clustering methods). Both methods converged with similar results providing precise segmentation over multiple Raman images of studied tissues.
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González-Sáiz, José-María; Esteban-Díez, Isabel; Rodríguez-Tecedor, Sofía; Pizarro, Consuelo
2008-11-01
The overall purpose of the project, of which this study is a part, was to examine the feasibility of onion waste as a support-substrate for the profitable production of food-grade products. This study focused on the efficient production of ethanol from worthless onions by transforming the onion juice into onion liquor via alcoholic fermentation with the yeast Saccharomyces cerevisiae. The onion bioethanol produced could be later used as a favorable substrate for acetic fermentation to finally obtain onion vinegar. Near-infrared spectroscopy (NIRS), coupled with the multivariate curve resolution-alternating least squares (MCR-ALS) method, has been used to reveal the compositional and spectral profiles for both substrates and products of alcoholic fermentation runs, that is, total sugars, ethanol, and biomass concentration. The ambiguity associated with the ALS calculation was resolved by applying suitable inequality and equality constraints. The quality of the results provided by the NIR-based MCR-ALS methodology adopted was evaluated by several performance indicators, including the variance explained by the model, the lack of fit and the agreement between the MCR-ALS achieved solution and the results computed by applying previously validated PLS reference models. An additional fermentation run was employed to test the actual predictive ability of the ALS model developed. For all the components resolved in the fermentation system studied (i.e., total sugars, ethanol, and biomass), the final model obtained showed a high predictive ability and suitable accuracy and precision, both in calibration and external validation, confirmed by the very good agreement between the ALS responses and the reference values (the coefficient of determination was, in all cases, very close to 1, and the statistics confirmed that no significant difference was found between PLS reference models and the MCR-ALS methodology applied). Thus, the proven reliability of the MCR-ALS model presented
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NASA Astrophysics Data System (ADS)
Sacriste, D.; Goubot, N.; Dhers, J.; Ducos, M.; Vardelle, A.
2001-06-01
The high power plasma torch (PlazJet) can be used to spray refractory ceramics with high spray rates and deposition efficiency. It can provide dense and hard coating with high bond strengths. When manufacturing thermal barrier coatings, the PlazJet gun is well adapted to spraying the ceramic top coat but not the MCrAIY materials that are used as bond coat. Arc spraying can compete with plasma spraying for metallic coatings since cored wires can be used to spray alloys and composites. In addition, the high production rate of arc spraying enables a significant decrease in coating cost. This paper discusses the performances of the PlazJet gun, and a twin-wire are spray system, and compares the properties and cost of MCrAIY coatings made with these two processes. For arc spraying, the use of air or nitrogen as atomizing gas is also investigated.
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Development of Oxide Dispersion Strengthened MCrAlY Coatings
NASA Astrophysics Data System (ADS)
Bobzin, K.; Schläfer, T.; Richardt, K.; Brühl, M.
2008-12-01
MCrAlY materials are widely used as bond coats for thermal barrier coatings on turbine blades. The aim of this work is to improve mechanical properties and wear resistance of thermal sprayed NiCoCrAlY-coatings by strengthening the coating with hard phase particles. In order to retain the effect of the dispersion reinforcement at high temperatures, the use of temperature-stable oxide hard phases such as ZrO2-Y2O3 is necessary. To realize this new material structure, the high-energy ball-milling process is applied and analyzed. The mixture ratio between NiCoCrAlY and ZrO2-Y2O3 was varied between 5 and 10 wt.% ZrO2-Y2O3. The influences of the milling time of the high-energy ball-milling process on the distribution of the hard phases in the metal matrix were analyzed. After spraying with a HVOF system the mechanical properties of the coatings are measured and compared with conventional NiCoCrAlY coatings.
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Tacão, Marta; Tavares, Rafael Dos Santos; Teixeira, Pedro; Roxo, Inês; Ramalheira, Elmano; Ferreira, Sónia; Henriques, Isabel
2017-08-01
Escherichia coli Ec36 was recovered from a patient in Portugal after treatment with meropenem and colistin. Besides an IncF plasmid with Tn1441d-bla KPC-3 , already reported in clinical strains in this country, E. coli Ec36 co-harbored an IncX4::mcr-1 gene. Results highlight emerging co-resistance to carbapenems and polymyxins after therapy with drugs from both classes.
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The Death Throes of Ocean Core Complexes: Examples from the Mid-Cayman Spreading Centre
NASA Astrophysics Data System (ADS)
Cheadle, M. J.; John, B. E.; German, C. R.; Kusznir, N. J.
2012-12-01
The Mid-Cayman Spreading Centre (MCSC) is an ultraslow (full rate 15-17 mm/yr) mid-ocean ridge that is located within the Cayman Trough, at the boundary between the North American and Caribbean plates. It is 110km long, and at ~6km below sea level, is the deepest spreading centre in the world. In the Summer of 2011, during NOAA EX 1104, the RV Okeanos Explorer collected high resolution (50m) Simrad EM302 multibeam bathymetry, and high-resolution video using the ROV Little Hercules ,which together provide insight into the evolution (from birth to death) of oceanic core complexes (OCCs). The MCSC exhibits bathymetry typical of slow spreading, magmatically deficient, ridges with thick lithosphere. It has both well-developed OCCs with ~15km of detachment fault offset and smaller offset (6-7km) normal faults forming >40km long linear ridges. Mass wasting is conspicuous. The MCSC is flanked on both sides by three oceanic core complexes: i) the now inactive, Mount Emms to the northeast, ii) the near-recently active Mount Dent in the west centre of the axial valley, and iii) the decapitated Mount Hudson on the south east flank. Together these massifs show different stages of OCC termination. Mount Emms lies approximately 2Ma off axis, is the oldest of the OCCs, and is heavily dissected by faulting and mass wasting. Mount Hudson is terminated by a west dipping high angle normal fault, with 1.6km throw and was initially rifted apart ~0.5Ma. A recently active axial volcanic ridge (AVR) with ROV observed pahoehoe lava forms, and a line of conical volcanic edifices lie within the rifted remains at the toe of the OCC. In contrast, Mount Dent was the most recently active, but is now in the very initial stages of being rifted apart by the presently active AVR that currently intersects the OCC. Incipient high angle normal faults that lie along strike of the AVR cut the dome of Mount Dent, and host the active von Damm hydrothermal system. Mount Dent also shows excess (>1km) uplift
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Rivero, M J; Parsons, S A; Jeffrey, P; Pidou, M; Jefferson, B
2006-01-01
Urban water recycling is now becoming an important issue where water resources are becoming scarce. This paper looks at reusing grey water; the preference is treatment processes based on biological systems to remove the dissolved organic content. Here, an alternative process, photocatalysis is discussed as it is an attractive technology that could be well-suited for treating the recalcitrant organic compounds found in grey water. The photocatalytic process oxidises organic reactants at a catalyst surface in the presence of ultraviolet light. Given enough exposure time, organic compounds will be oxidized into CO2 and water. The best contact is achieved in a slurry reactor but a second step to separate and recover the catalyst is need. This paper discusses a new membrane chemical reactor (MCR) combining photocatalysis and microfiltration for grey water treatment.
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Gomez-Vidal, Judith C.; Noel, John; Weber, Jacob
2016-07-30
Here, stainless steels (SS) 310, 321, 347, Incoloy 800H (In800H), alumina-forming austenitic (AFA-OC6), Ni superalloy Inconel 625 (IN625), and MCrAlX (M: Ni, and/or Co; X: Y, Hf, Si, and/or Ta) coatings were corroded in molten carbonates in N 2 and bone-dry CO 2 atmospheres. Electrochemical tests in molten eutectics K 2CO 3-Na 2CO 3 and Na 2CO 3-K 2CO 3-Li 2CO 3 at temperatures higher than 600 °C were evaluated using an open-circuit potential followed by a potentiodynamic polarization sweep to determine the corrosion rates. Because the best-performing alloys at 750 °C were In800H followed by SS310, these two alloysmore » were selected as the substrate material for the MCrAlX coatings. The coatings were able to mitigate corrosion in molten carbonates environments. The corrosion of substrates SS310 and In800H was reduced from ~2500 um/year to 34 um/year when coated with high-velocity oxyfuel (HVOF) NiCoCrAlHfSiY and pre-oxidized (air, 900 °C, 24 h, 0.5 °C/min) before molten carbonate exposure at 700 °C in bone-dry CO 2 atmosphere. Metallographic characterization of the corroded surfaces showed that the formation of a uniform alumina scale during the pre-oxidation seems to protect the alloy from the molten carbonate attack.« less
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Tang, Yongjiao; Jing, Nan; Zhang, Pudun
2015-11-01
A series of chlorobutyl rubber/polyamide-12 (CIIR/PA-12) blends compatibilized by different amounts of maleic anhydride (MAH) grafted polypropylene (PP-g-MAH) were investigated by attenuated total reflection Fourier transform infrared spectroscopy (ATR FT-IR) mapping. Multivariate curve resolution (MCR) was used to process the FT-IR images. Both the spectra of pure components in the blends and their concentration distributions in a micro-region were acquired. Our results demonstrated that the blend with 15 parts per hundred rubber PP-g-MAH showed the best miscibility. An amide interphase and an imide interphase were inferred by analyzing the spectra of MCR component 3 of the blends with and without PP-g-MAH, respectively. Correspondingly, two different compatibilizing mechanisms were proposed for these blends.
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Seismic structure and segmentation of the axial valley of the Mid-Cayman Spreading Center
NASA Astrophysics Data System (ADS)
Van Avendonk, Harm J. A.; Hayman, Nicholas W.; Harding, Jennifer L.; Grevemeyer, Ingo; Peirce, Christine; Dannowski, Anke
2017-06-01
We report the results of a two-dimensional tomographic inversion of marine seismic refraction data from an array of ocean-bottom seismographs (OBSs), which produced an image of the crustal structure along the axial valley of the ultraslow spreading Mid-Cayman Spreading Center (MCSC). The seismic velocity model shows variations in the thickness and properties of the young oceanic crust that are consistent with the existence of two magmatic-tectonic segments along the 110 km long spreading center. Seismic wave speeds are consistent with exhumed mantle at the boundary between these two segments, but changes in the vertical gradient of seismic velocity suggest that volcanic crust occupies most of the axial valley seafloor along the seismic transect. The two spreading segments both have a low-velocity zone (LVZ) several kilometers beneath the seafloor, which may indicate the presence of shallow melt. However, the northern segment also has low seismic velocities (3 km/s) in a thick upper crustal layer (1.5-2.0 km), which we interpret as an extrusive volcanic section with high porosity and permeability. This segment hosts the Beebe vent field, the deepest known high-temperature black smoker hydrothermal vent system. In contrast, the southern spreading segment has seismic velocities as high as 4.0 km/s near the seafloor. We suggest that the porosity and permeability of the volcanic crust in the southern segment are much lower, thus limiting deep seawater penetration and hydrothermal recharge. This may explain why no hydrothermal vent system has been found in the southern half of the MCSC.
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Hancewicz, Thomas M; Xiao, Chunhong; Zhang, Shuliang; Misra, Manoj
2013-12-01
In vivo confocal Raman spectroscopy has become the measurement technique of choice for skin health and skin care related communities as a way of measuring functional chemistry aspects of skin that are key indicators for care and treatment of various skin conditions. Chief among these techniques are stratum corneum water content, a critical health indicator for severe skin condition related to dryness, and natural moisturizing factor components that are associated with skin protection and barrier health. In addition, in vivo Raman spectroscopy has proven to be a rapid and effective method for quantifying component penetration in skin for topically applied skin care formulations. The benefit of such a capability is that noninvasive analytical chemistry can be performed in vivo in a clinical setting, significantly simplifying studies aimed at evaluating product performance. This presumes, however, that the data and analysis methods used are compatible and appropriate for the intended purpose. The standard analysis method used by most researchers for in vivo Raman data is ordinary least squares (OLS) regression. The focus of work described in this paper is the applicability of OLS for in vivo Raman analysis with particular attention given to use for non-ideal data that often violate the inherent limitations and deficiencies associated with proper application of OLS. We then describe a newly developed in vivo Raman spectroscopic analysis methodology called multivariate curve resolution-augmented ordinary least squares (MCR-OLS), a relatively simple route to addressing many of the issues with OLS. The method is compared with the standard OLS method using the same in vivo Raman data set and using both qualitative and quantitative comparisons based on model fit error, adherence to known data constraints, and performance against calibration samples. A clear improvement is shown in each comparison for MCR-OLS over standard OLS, thus supporting the premise that the MCR
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Motegi, Hiromi; Tsuboi, Yuuri; Saga, Ayako; Kagami, Tomoko; Inoue, Maki; Toki, Hideaki; Minowa, Osamu; Noda, Tetsuo; Kikuchi, Jun
2015-11-04
There is an increasing need to use multivariate statistical methods for understanding biological functions, identifying the mechanisms of diseases, and exploring biomarkers. In addition to classical analyses such as hierarchical cluster analysis, principal component analysis, and partial least squares discriminant analysis, various multivariate strategies, including independent component analysis, non-negative matrix factorization, and multivariate curve resolution, have recently been proposed. However, determining the number of components is problematic. Despite the proposal of several different methods, no satisfactory approach has yet been reported. To resolve this problem, we implemented a new idea: classifying a component as "reliable" or "unreliable" based on the reproducibility of its appearance, regardless of the number of components in the calculation. Using the clustering method for classification, we applied this idea to multivariate curve resolution-alternating least squares (MCR-ALS). Comparisons between conventional and modified methods applied to proton nuclear magnetic resonance ((1)H-NMR) spectral datasets derived from known standard mixtures and biological mixtures (urine and feces of mice) revealed that more plausible results are obtained by the modified method. In particular, clusters containing little information were detected with reliability. This strategy, named "cluster-aided MCR-ALS," will facilitate the attainment of more reliable results in the metabolomics datasets.
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Order-disorder effects on the elastic properties of CuMPt6 (M=Cr and Co) compounds
NASA Astrophysics Data System (ADS)
Huang, Shuo; Li, Rui-Zi; Qi, San-Tao; Chen, Bao; Shen, Jiang
2014-04-01
The elastic properties of CuMPt6 (M=Cr and Co) in disordered face-centered cubic (fcc) structure and ordered Cu3Au-type structure are studied with lattice inversion embedded-atom method. The calculated lattice constant and Debye temperature agree quite well with the comparable experimental data. The obtained formation enthalpy demonstrates that the Cu3Au-type structure is energetically more favorable. Numerical estimates of the elastic constants, bulk/shear modulus, Young's modulus, Poisson's ratio, elastic anisotropy, and Debye temperature for both compounds are performed, and the results suggest that the disordered fcc structure is much softer than the ordered Cu3Au-type structure.
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NASA Astrophysics Data System (ADS)
Elsaß, M.; Frommherz, M.; Oechsner, M.
2018-02-01
In this work, interdiffusion between two nickel-based superalloys and two MCrAlY bond coats is investigated. The MCrAlY bond coats were applied using two different spraying processes, high velocity oxygen fuel spraying (HVOF) and low-pressure plasma spraying. Of primary interest is the evolution of Kirkendall porosity, which can form at the interface between substrate and bond coat and depends largely on the chemical compositions of the coating and substrate. Experimental evidence further suggested that the formation of Kirkendall porosity depends on the coating deposition process. Formation of porosity at the interface causes a degradation of the bonding strength between substrate and coating. After coating deposition, the samples were annealed at 1050 °C for up to 2000 h. Microstructural and compositional analyses were performed to determine and evaluate the Kirkendall porosity. The results reveal a strong influence of both the coating deposition process and the chemical compositions. The amount of Kirkendall porosity formed, as well as the location of appearance, is largely influenced by the coating deposition process. In general, samples with bond coats applied by means of HVOF show accelerated element diffusion. It is hypothesized that recrystallization of the substrate material is a main root cause for these observations.
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Lourenço de Oliveira, Ricardo; Vazeille, Marie; de Filippis, Ana Maria Bispo; Failloux, Anna-Bella
2003-07-01
We conducted a population genetic analysis of Aedes albopictus collected from 20 sites in Brazil, the United States (Florida, Georgia, and Illinois), and the Cayman Islands. Using isoenzyme analysis, we examined genetic diversity and patterns of gene flow. High genetic differentiation was found among Brazilian samples, and between them and North American samples. Regression analysis of genetic differentiation according to geographic distances indicated that Ae. albopictus samples from Florida were genetically isolated by distance. Infection rates with dengue and yellow fever viruses showed greater differences between two Brazilian samples than between the two North American samples or between a Brazilian sample and a North American sample. Introductions and establishments of new Ae. albopictus populations in the Americas are still in progress, shaping population genetic composition and potentially modifying both dengue and yellow fever transmission patterns.
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NASA Astrophysics Data System (ADS)
Versteegh, Emma; Van Dover, Cindy; Coleman, Max
2014-05-01
Most hydrothermal vents support productive communities, with chemosynthetic bacteria at the base of the food web. They form a potentially important link in global geochemical cycles. However, few data yet exist on their significance in ocean biogeochemistry and related ecological processes. We present results on the structure of part of the food web around hydrothermal vents of the Mid-Cayman Rise (MCR), revealing previously unknown life-history traits of the alvinocarid shrimp species Rimicaris hybisae. We also demonstrate that stable carbon isotope ratios (δ13C values) are an excellent tracer of trophic positions in these ecosystems, in spite of recent findings arguing otherwise. Two hydrothermal vent fields have been described at the ultra-slow spreading ridge of the MCR. These include the world's deepest hydrothermal vents (Piccard field ~4985 m), which support a food web, which includes bactivorous shrimp and carnivorous anemones. The nearby Von Damm vent field (~2300 m) supports a more complex food web, with more primary producers, and probably some influx of photosynthetically produced carbon. Rimicaris hybisae is abundant at both known MCR vent fields and shows a high degree of spatial variability in population structure and reproductive features. In previous work it has been considered bactivorous. Large variations in tissue δ13C values remained largely unexplained, and it has been argued that δ13C values are not a good food web tracer in hydrothermal vent ecosystems. We observed that shrimp tended to be either in dense aggregations on active chimneys or more sparsely distributed, peripheral shrimp in ambient or near-ambient temperatures. With the hypothesis that varying δ13C values show real differences in food sources between individuals and that shrimp in different locales might have different diets, we collected shrimp from both environments at the Von Damm site during E/V Nautilus (NA034, August 2013) and examined their gut contents. Stomach
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Liu, Guohong; Weston, Christopher Q; Pham, Long K; Waltz, Shannon; Barnes, Helen; King, Paula; Sphar, Dan; Yamamoto, Robert T; Forsyth, R Allyn
2016-01-01
We describe continuing work to develop restriction endonucleases as tools to enrich targeted genomes of interest from diverse populations. Two approaches were developed in parallel to segregate genomic DNA based on cytosine methylation. First, the methyl-sensitive endonuclease HpaII was used to bind non-CG methylated DNA. Second, a truncated fragment of McrB was used to bind CpG methylated DNA. Enrichment levels of microbial genomes can exceed 100-fold with HpaII allowing improved genomic detection and coverage of otherwise trace microbial genomes from sputum. Additionally, we observe interesting enrichment results that correlate with the methylation states not only of bacteria, but of fungi, viruses, a protist and plants. The methods presented here offer promise for testing biological samples for pathogens and global analysis of population methylomes.
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La, My-Van; Lin, Raymond T. P.
2017-01-01
ABSTRACT Colistin and polymyxin B remain part of the last line of antibiotics for multidrug-resistant Gram-negative bacteria, such as carbapenem-resistant Enterobacteriaceae. Current joint EUCAST-CLSI recommendations are for broth microdilution (BMD) to be performed for MIC testing of colistin. Commercial susceptibility testing methods were evaluated and compared against the reference BMD, using a susceptibility breakpoint of ≤2 mg/liter for both colistin and polymyxin B. Seventy-six Enterobacteriaceae were included, of which 21 were mcr-1 positive (18 Escherichia coli isolates, 2 Klebsiella pneumoniae isolates, and 1 Enterobacter aerogenes isolate). Rates of essential agreement (EA) of colistin test results between BMD and Vitek 2, Sensititre, and Etest were 93.4%, 89.5%, and 75.0%, respectively. Rates of EA of polymyxin B test results between BMD and Vitek 2, Sensititre, and Etest were 96.1%, 96.1%, and 48.7%, respectively. A positive MIC correlation with a categorical agreement of >90% was achieved for Sensititre (colistin Spearman's ρ = 0.863, and polymyxin B Spearman's ρ = 0.877) and Vitek 2 (polymyxin B [only] Spearman's ρ = 0.8917). Although a positive MIC correlation (Spearman's ρ = 0.873) with the reference method was achieved for colistin testing with Vitek 2, categorical agreement was <90%, with very major error rates of 36%. Correlation with the Etest MIC was lower, with very major error rates of 12% (colistin) and 26.1% (polymyxin B). MicroScan (colistin) categorical agreement was 88.2%, with a very major error rate of 4%. Colistin MICs for 15 of the 21 mcr-1-positive isolates were >2 mg/liter, and polymyxin MICs for 17 of them were >2 mg/liter by broth microdilution. The use of a lower breakpoint of ≤1 mg/liter further improves detection of mcr-1 for all testing methods. However, further data on the correlation between MICs and clinical outcome are required to determine the most suitable breakpoint to guide clinical management. PMID:28592552
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-01-25
....; TCG Financial Services, L.P;, Carlyle Financial Services, Ltd.; TC Group Cayman Investment Holdings, L.P.; TCG Holdings Cayman II, L.P.; DBD Cayman, Limited; TCG Financial Services Investment Holdings, L...'Aniello; William E. Conway, Jr.; David M. Rubenstein, all in Washington, D.C.; and Carlyle Investment...
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Smith, Joseph P; Smith, Frank C; Ottaway, Joshua; Krull-Davatzes, Alexandra E; Simonson, Bruce M; Glass, Billy P; Booksh, Karl S
2017-08-01
The high-pressure, α-PbO 2 -structured polymorph of titanium dioxide (TiO 2 -II) was recently identified in micrometer-sized grains recovered from four Neoarchean spherule layers deposited between ∼2.65 and ∼2.54 billion years ago. Several lines of evidence support the interpretation that these layers represent distal impact ejecta layers. The presence of shock-induced TiO 2 -II provides physical evidence to further support an impact origin for these spherule layers. Detailed characterization of the distribution of TiO 2 -II in these grains may be useful for correlating the layers, estimating the paleodistances of the layers from their source craters, and providing insight into the formation of the TiO 2 -II. Here we report the investigation of TiO 2 -II-bearing grains from these four spherule layers using multivariate curve resolution-alternating least squares (MCR-ALS) applied to Raman microspectroscopic mapping. Raman spectra provide evidence of grains consisting primarily of rutile (TiO 2 ) and TiO 2 -II, as shown by Raman bands at 174 cm -1 (TiO 2 -II), 426 cm -1 (TiO 2 -II), 443 cm -1 (rutile), and 610 cm -1 (rutile). Principal component analysis (PCA) yielded a predominantly three-phase system comprised of rutile, TiO 2 -II, and substrate-adhesive epoxy. Scanning electron microscopy (SEM) suggests heterogeneous grains containing polydispersed micrometer- and submicrometer-sized particles. Multivariate curve resolution-alternating least squares applied to the Raman microspectroscopic mapping yielded up to five distinct chemical components: three phases of TiO 2 (rutile, TiO 2 -II, and anatase), quartz (SiO 2 ), and substrate-adhesive epoxy. Spectral profiles and spatially resolved chemical maps of the pure chemical components were generated using MCR-ALS applied to the Raman microspectroscopic maps. The spatial resolution of the Raman microspectroscopic maps was enhanced in comparable, cost-effective analysis times by limiting spectral resolution
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-06-07
... Investment Management, L.L.C.; TC Group, L.L.C.; and TCG Holdings, L.L.C., all of Wilmington, Delaware; to... Partners, L.P.; TCG Financial Services, L.P.; Carlyle Financial Services, Ltd.; TC Group Cayman Investment Holdings, L.P.; TCG Holdings Cayman II, L.P.; DBD Cayman, Limited; TCG Financial Services Investment...
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Smith, Joseph P; Smith, Frank C; Booksh, Karl S
2017-08-21
The search for evidence of extant or past life on Mars is a primary objective of both the upcoming Mars 2020 rover (NASA) and ExoMars 2020 rover (ESA/Roscosmos) missions. This search will involve the detection and identification of organic molecules and/or carbonaceous material within the Martian surface environment. For the first time on a mission to Mars, the scientific payload for each rover will include a Raman spectrometer, an instrument well-suited for this search. Hematite (α-Fe 2 O 3 ) is a widespread mineral on the Martian surface. The 2LO Raman band of hematite and the Raman D-band of carbonaceous material show spectral overlap, leading to the potential misidentification of hematite as carbonaceous material. Here we report the ability to spatially and spectrally differentiate carbonaceous material from hematite using multivariate curve resolution-alternating least squares (MCR-ALS) applied to Raman microspectroscopic mapping under both 532 nm and 785 nm excitation. For this study, a sample comprised of hematite, carbonaceous material, and substrate-adhesive epoxy in spatially distinct domains was constructed. Principal component analysis (PCA) reveals that both 532 nm and 785 nm excitation produce representative three-phase systems of hematite, carbonaceous material, and substrate-adhesive epoxy in the analyzed sample. MCR-ALS with Raman microspectroscopic mapping using both 532 nm and 785 nm excitation was able to resolve hematite, carbonaceous material, and substrate-adhesive epoxy by generating spatially-resolved chemical maps and corresponding Raman spectra of these spatially distinct chemical species. Moreover, MCR-ALS applied to the combinatorial data sets of 532 nm and 785 nm excitation, which contain hematite and carbonaceous material within the same locations, was able to resolve hematite, carbonaceous material, and substrate-adhesive epoxy. Using multivariate analysis with Raman microspectroscopic mapping, 785 nm excitation more effectively
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NASA Astrophysics Data System (ADS)
Alcaráz, Mirta R.; Schwaighofer, Andreas; Goicoechea, Héctor; Lendl, Bernhard
2017-10-01
Temperature-induced conformational transitions of poly-L-lysine were monitored with Fourier-transform infrared (FT-IR) spectroscopy between 10 °C and 70 °C. Chemometric analysis of dynamic IR spectra was performed by multivariate curve analysis-alternating least squares (MCR-ALS) of the amide I‧ and amide II‧ spectral region. With this approach, the pure spectral and concentration profiles of the conformational transition were obtained. Beside the initial α-helical, the intermediate random coil/extended helices and the final β-sheet structure, an additional intermediate PLL conformation was identified and attributed to a transient β-sheet structure.
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NASA Astrophysics Data System (ADS)
Sakai, Yoshiko; Miyoshi, Eisaku
1987-09-01
Electronic structures of MF6, MF-6, and MF2-6 (M=Cr, Mo, and W) were calculated using a model potential method in the Hartree-Fock-Roothaan scheme. Major relativistic effects were taken into account for the calculations on MoFq6 and WFq6 (q=0, -1, and -2). It is shown that the calculated electron affinities (EAs) are extremely high for all the MF6 molecules, and that the CrF-6 and MoF-6 anions also have positive EAs, whereas the WF-6 anion has a slightly negative EA. The behaviors of the EAs are interpreted with reference to the electronic structures of the MFq6 systems.
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NASA Astrophysics Data System (ADS)
Jones, Brian
2010-12-01
A wave-cut notch that is deeply incised into the vertical cliff faces of Cayman Brac is adorned with stalactites, stalagmites, and columns. The prefix "notch" is applied to each type of speleothem in order to distinguish them from cave speleothems. These speleothemic deposits must have formed since the highstand, ~ 125,000 years ago, which was responsible for the development of the notch. The laminated notch speleothems are formed largely of aragonite (small and large crystals) and calcite (columnar, fiber, and grain-coating mats) along with minor amounts of dolomite, a Mg-Si precipitate (kerolite?), gypsum, and halite. Laminae, typically < 2 mm thick, are commonly bounded by dissolution discontinuities that truncate the older laminae and their formative aragonite and calcite crystals. The patchy tan, grey, to green surface coloration of the notch speleothems reflects the random distribution of the subaerial biofilms, which are formed of a diverse array of filamentous and non-filamentous microbes. The notch speleothems are the integrated product of precipitation and dissolution that was, in some places, microbially mediated. Interpretations based on their mineralogy and internal structures indicate that the composition of the formative waters must have temporally fluctuated with periods of precipitation being interrupted by periods of dissolution. The microbes that formed the subaerial biofilms may have influenced some of these processes. The aragonite, calcite, and kerolite (?) probably formed as evaporation and loss of Ca through precipitation progressively increased the Mg:Ca and the Si/(Ca + Mg) ratios. The dolomite, gypsum, and halite probably formed during early diagenesis during the evaporation of seawater that percolated into the interiors of the notch speleothems.
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NASA Technical Reports Server (NTRS)
Deadmore, D. L.
1974-01-01
Cermet, MCrAl, and modified aluminide types of coatings applied to IN-100 and NASA-TRW-VIA alloy specimens were cyclically oxidation tested in a high velocity (Mach 1) gas flame at 1093 C. Several coating compositions of each type were evaluated for oxidation resistance. The modified aluminide coating, Pt-Al, applied to alloy 6A proved to be the best, providing oxidation protection to approximately 750 hours based on weight change measurements. The second best, a CoCrAlY coating applied to 6A, provided protection to 450 hours. The third best was a cermet + aluminide coating on 6A with a protection time to 385 hours.
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75 FR 6396 - Change in Bank Control Notices; Acquisition of Shares of Bank or Bank Holding Companies
Federal Register 2010, 2011, 2012, 2013, 2014
2010-02-09
...., both of George Town, Cayman Islands; Capital Z Partners Management, LLC, Dover, Delaware; Capital Z Partners III, L.P., George Town, Cayman Islands; and Bradley E. Cooper, and Robert A. Spass, both of New...
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NASA Astrophysics Data System (ADS)
Harding, J.; Van Avendonk, H. J.; Hayman, N. W.; Grevemeyer, I.; Peirce, C.; Dannowski, A.; Papenberg, C. A.
2015-12-01
The CaySEIS experiment, conducted in April 2015, is a multi-national collaborative seismic study of the Mid Cayman Spreading Center (MCSC), an ultra-slow spreading center [15 mm/yr fr] in the Caribbean Sea. Ultra-slow spreading centers are thought to have very thin crust and a paucity of magmatism due to cooler mantle conditions. However, the suggestion that gabbro-cored oceanic core complexes (OCCs), volcanic deposits, and multiple layers of hydrothermal vents are widespread in the MCSC and other ultra-slow spreading centers has led to questions about the relationship between seafloor spreading rates and magmatism. To investigate this further, we conducted the CaySEIS experiment, with five wide-angle seismic refraction lines parallel and perpendicular to the neovolcanic zone. This analysis is based on two east-west oriented 100-km-long seismic refraction lines, which were each occupied by 18 ocean bottom seismometers. Line 2 lies across the central MCSC and an OCC called Mt. Dent. Line 3 crosses the northern end of the MCSC near the Oriente Transform Zone. With the wide-angle OBS data we can image the seismic velocity structure of Mt. Dent and distinguish between two models of OCCs - either Mt. Dent is composed of mostly gabbro with peridotite lenses identified by a low velocity gradient, or it is composed of mostly peridotite with gabbroic bodies identified by a constant velocity gradient. The crustal structure of both lines gives more insight into the asymmetry of the MCSC and the style of seafloor spreading to the east vs. the west. The 2-D velocity models reveal Mt. Dent has thick crust of 8 km with a low velocity gradient, supporting the magmatic gabbroic origin of OCCs. The surrounding crust to the west of the MCSC is highly variable, with areas of very thin crust. The crust to the east of the MCSC has an approximately constant thickness of 4 km. The development of OCCs may contribute to the crustal heterogeneity of ultra-slow spreading centers.
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Lengger, Sandra; Otto, Johannes; Elsässer, Dennis; Schneider, Oliver; Tiehm, Andreas; Fleischer, Jens; Niessner, Reinhard; Seidel, Michael
2014-05-01
Pathogenic viruses are emerging contaminants in water which should be analyzed for water safety to preserve public health. A strategy was developed to quantify RNA and DNA viruses in parallel on chemiluminescence flow-through oligonucleotide microarrays. In order to show the proof of principle, bacteriophage MS2, ΦX174, and the human pathogenic adenovirus type 2 (hAdV2) were analyzed in spiked tap water samples on the analysis platform MCR 3. The chemiluminescence microarray imaging unit was equipped with a Peltier heater for a controlled heating of the flow cell. The efficiency and selectivity of DNA hybridization could be increased resulting in higher signal intensities and lower cross-reactivities of polymerase chain reaction (PCR) products from other viruses. The total analysis time for DNA/RNA extraction, cDNA synthesis for RNA viruses, polymerase chain reaction, single-strand separation, and oligonucleotide microarray analysis was performed in 4-4.5 h. The parallel quantification was possible in a concentration range of 9.6 × 10(5)-1.4 × 10(10) genomic units (GU)/mL for bacteriophage MS2, 1.4 × 10(5)-3.7 × 10(8) GU/mL for bacteriophage ΦX174, and 6.5 × 10(3)-1.2 × 10(5) for hAdV2, respectively, by using a measuring temperature of 40 °C. Detection limits could be calculated to 6.6 × 10(5) GU/mL for MS2, 5.3 × 10(3) GU/mL for ΦX174, and 1.5 × 10(2) GU/mL for hAdV2, respectively. Real samples of surface water and treated wastewater were tested. Generally, found concentrations of hAdV2, bacteriophage MS2, and ΦX174 were at the detection limit. Nevertheless, bacteriophages could be identified with similar results by means of quantitative PCR and oligonucleotide microarray analysis on the MCR 3.
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Weide, Tobias; Guschin, Viktor; Becker, Wolfgang; Koelle, Sabine; Maier, Simon; Seidelt, Stephan
2015-01-01
The analysis of tar, mostly characterized as polycyclic aromatic hydrocarbons (PAHs), describes a topic that has been researched for years. An online analysis of tar in the gas stream in particular is needed to characterize the tar conversion or formation in the biomass gasification process. The online analysis in the gas is carried out with ultraviolet-visible (UV-Vis) spectroscopy (190-720 nm). This online analysis is performed with a measuring cell developed by the Fraunhofer Institute for Chemical Technology (ICT). To this day, online tar measurements using UV-Vis spectroscopy have not been carried out in detail. Therefore, PAHs are analyzed as follows. The measurements are split into different steps. The first step to prove the online method is to vaporize single tar substances. These experiments show that a qualitative analysis of PAHs in the gas stream with the used measurement setup is possible. Furthermore, it is shown that the method provides very exact results, so that a differentiation of various PAHs is possible. The next step is to vaporize a PAH mixture. This step consists of vaporizing five pure substances almost simultaneously. The interpretation of the resulting data is made using a chemometric interpretation method, the multivariate curve resolution (MCR). The verification of the calculated results is the main aim of this experiment. It has been shown that the tar mixture can be analyzed qualitatively and quantitatively (in arbitrary units) in detail using the MCR. Finally it is the main goal of this paper to show the first steps in the applicability of the UV-Vis spectroscopy and the measurement setup on online tar analysis in view of characterizing the biomass gasification process. Due to that, the gasification plant (at the laboratory scale), developed and constructed by the Fraunhofer ICT, has been used to vaporize these substances. Using this gasification plant for the experiments enables the usage of the measurement setup also for the
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NASA Astrophysics Data System (ADS)
Harding, J.; Van Avendonk, H. J.; Hayman, N. W.; Grevemeyer, I.; Peirce, C.
2016-12-01
The Mid Cayman Spreading Center (MCSC) is an ultraslow-spreading center (15 mm yr-1 full rate) along the Caribbean-North American plate boundary. Despite the paradigm that ultraslow-spreading centers are amagmatic and cold, two hydrothermal vent fields have recently been discovered along the MCSC. The Beebe Vent Field is a black smoker in the northern axial deep, and the Von Damm Vent Field (VDVF) is a moderate-temperature, talc precipitating vent found atop an oceanic core complex (OCC). This OCC, "Mt. Dent", is a large (3 km high) massif that formed beneath a detachment fault, which exhumed lower crustal and upper mantle material. The CaySeis Experiment was conducted in April, 2015 in order to collect wide-angle refraction data of the MCSC crust and upper mantle. We modeled the across-axis crustal structure of Mt. Dent as well as the surrounding lithosphere using 2.5D P-wave tomography. Using this tomographic model, along with geochemistry, we propose a model for the formation and evolution of the OCC Mt. Dent and the VDVF. A detachment fault formed in a magma-poor environment due to a pulse of magmatism, producing a large gabbro body that was then exhumed and rotated into the OCC footwall. Once magmatism waned and the gabbroic body cooled, the OCC was faulted and fractured due to plate flexure and increased tectonic extensional stress in the naturally cold and thick lithosphere. These faults provide a permeable and deep network of hydrothermal pathways that mine deep lithospheric heat and expose gabbro and fresh mantle peridotite. This model is consistent with the basalt geochemistry, hydrothermal fluid geochemistry, and the distribution of brittle vs. ductile structures along the detachment shear zone. The VDVF is therefore a product of a pulse of magmatism in an overall melt-poor environment, conditions that may be found at other ultraslow-spreading ridges.
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NASA Astrophysics Data System (ADS)
Sandi, Steven G.; Rodríguez, José F.; Saintilan, Neil; Riccardi, Gerardo; Saco, Patricia M.
2018-04-01
Coastal wetlands are vulnerable to submergence due to sea-level rise, as shown by predictions of up to 80% of global wetland loss by the end of the century. Coastal wetlands with mixed mangrove-saltmarsh vegetation are particularly vulnerable because sea-level rise can promote mangrove encroachment on saltmarsh, reducing overall wetland biodiversity. Here we use an ecogeomorphic framework that incorporates hydrodynamic effects, mangrove-saltmarsh dynamics, and soil accretion processes to assess the effects of control structures on wetland evolution. Migration and accretion patterns of mangrove and saltmarsh are heavily dependent on topography and control structures. We find that current management practices that incorporate a fixed gate for the control of mangrove encroachment are useful initially, but soon become ineffective due to sea-level rise. Raising the gate, to counteract the effects of sea level rise and promote suitable hydrodynamic conditions, excludes mangrove and maintains saltmarsh over the entire simulation period of 100 years
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NASA Technical Reports Server (NTRS)
Ramsey, P.; Robertson, M. K.
1973-01-01
A test of a 0.004-scale MCR 0074 Baseline Launch Configuration Space Shuttle model was conducted in the NASA-MSFC 14 x 14-inch Trisonic Wind Tunnel (MSFC TWT 566). The objective of the test was to determine the effects of model parametric variations on aerodynamic static stability characteristics over a Mach number range from 0.6 to 4.96. Angles-of-attack from minus 10 deg to plus 10 deg at 0 deg sideslip and angles-of-sideslip from minus 10 deg to plus 10 deg at minus 5 deg, 0 deg, and plus 5 deg angle-of-attack were investigated. The basic configuration investigated was the integrated vehicle consisting of the orbiter, and external tank, and two solid rocket boosters. It was designated 03T9S3.
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Huang, Te Din; Bogaerts, Pierre; Berhin, Catherine; Hoebeke, Martin; Bauraing, Caroline; Glupczynski, Youri
2017-05-11
Carbapenemase-producing Enterobacteriaceae (CPE) strains have been increasingly reported in Belgium. We aimed to determine the proportion of CPE among Enterobacteriaceae isolated from hospitalised patients and community outpatients in Belgium in 2015. For the hospitalised patients, the results were compared to a previous similar survey performed in the same hospitals in 2012. Twenty-four hospital-based and 10 private laboratories collected prospectively 200 non-duplicated Enterobacteriaceae isolates from clinical specimens. All isolates were screened locally by carbapenem disk diffusion using European Committee on Antimicrobial Susceptibility Testing methodology. Putative CPE strains with inhibition zone diameters below the screening breakpoints were referred centrally for confirmation of carbapenemase production. From September to November 2015, we found a proportion of clinical CPE of 0.55% (26/4,705) and of 0.60% (12/1,991) among hospitalised patients and among ambulatory outpatients respectively. Klebsiella pneumoniae (26/38) and OXA-48-like carbapenemase (28/38) were the predominant species and enzyme among CPE. One OXA-48-producing Escherichia coli isolated from a hospital was found carrying plasmid-mediated MCR-1 colistin resistance. Compared with the 2012 survey, we found a significant increased proportion of clinical CPE (0.55% in 2015 vs 0.25% in 2012; p = 0.02) and an increased proportion of hospitals (13/24 in 2015 vs 8/24 in 2012) with at least one CPE detected. The study results confirmed the concerning spread of CPE including a colistin-resistant MCR-1 producer in hospitals and the establishment of CPE in the community in Belgium. This article is copyright of The Authors, 2017.
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Kubota, Kengo; Ohashi, Akiyoshi; Imachi, Hiroyuki; Harada, Hideki
2006-09-01
Two-pass tyramide signal amplification-fluorescence in situ hybridization (two-pass TSA-FISH) with a horseradish peroxidase (HRP)-labeled oligonucleotide probe was applied to detect prokaryotic mRNA. In this study, mRNA of a key enzyme for methanogenesis, methyl coenzyme M reductase (mcr), in Methanococcus vannielii was targeted. Applicability of mRNA-targeted probes to in situ hybridization was verified by Clone-FISH. It was observed that sensitivity of two-pass TSA-FISH was significantly higher than that of TSA-FISH, which was further increased by the addition of dextran sulphate in TSA working solution. Signals from two-pass TSA-FISH were more reliable compared to the weak, spotty signals yielded by TSA-FISH.
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NASA Technical Reports Server (NTRS)
Sweet, W. V.; Horton, R.; Kopp, R. E.; LeGrande, A. N.; Romanou, A.
2017-01-01
Global mean sea level (GMSL) has risen by about 7-8 inches (about 16-21 cm) since 1900, with about 3 of those inches (about 7 cm) occurring since 1993. Human-caused climate change has made a substantial contribution to GMSL rise since 1900, contributing to a rate of rise that is greater than during any preceding century in at least 2,800 years. Relative to the year 2000, GMSL is very likely to rise by 0.3-0.6 feet (9-18 cm) by 2030, 0.5-1.2 feet (15-38 cm) by 2050, and 1.0-4.3 feet (30-130 cm) by 2100. Future pathways have little effect on projected GMSL rise in the first half of the century, but significantly affect projections for the second half of the century. Emerging science regarding Antarctic ice sheet stability suggests that, for high emission scenarios, a GMSL rise exceeding 8 feet (2.4 m) by 2100 is physically possible, although the probability of such an extreme outcome cannot currently be assessed. Regardless of pathway, it is extremely likely that GMSL rise will continue beyond 2100. Relative sea level (RSL) rise in this century will vary along U.S. coastlines due, in part, to changes in Earth's gravitational field and rotation from melting of land ice, changes in ocean circulation, and vertical land motion (very high confidence). For almost all future GMSL rise scenarios, RSL rise is likely to be greater than the global average in the U.S. Northeast and the western Gulf of Mexico. In intermediate and low GMSL rise scenarios, RSL rise is likely to be less than the global average in much of the Pacific Northwest and Alaska. For high GMSL rise scenarios, RSL rise is likely to be higher than the global average along all U.S. coastlines outside Alaska. Almost all U.S. coastlines experience more than global mean sea level rise in response to Antarctic ice loss, and thus would be particularly affected under extreme GMSL rise scenarios involving substantial Antarctic mass loss. As sea levels have risen, the number of tidal floods each year that cause minor
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-12-02
... Associates IV LLC, WL Ross Group L.P., El Vedado LLC, all of New York, New York; Wilbur L. Ross, Jr., Palm... Master, Ltd., all of Grand Cayman, Cayman Islands; Anchorage Capital Partners, L.P., Anchorage Capital... Islands; and Carlyle Financial Services Harbor, L.P., Wilmington, Delaware; to acquire control of Central...
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NASA Astrophysics Data System (ADS)
Harding, J.; Van Avendonk, H. J.; Hayman, N. W.; Grevemeyer, I.; Peirce, C.
2017-12-01
The Mid-Cayman Spreading Center (MCSC), an ultraslow-spreading center in the Caribbean Sea, has formed highly variable oceanic crust. Seafloor dredges have recovered extrusive basalts in the axial deeps as well as gabbro on bathymetric highs and exhumed mantle peridotite along the only 110 km MCSC. Wide-angle refraction data were collected with active-source ocean bottom seismometers in April, 2015, along lines parallel and across the MCSC. Travel-time tomography produces relatively smooth 2-D tomographic models of compressional wave velocity. These velocity models reveal large along- and across-axis variations in seismic velocity, indicating possible changes in crustal thickness, composition, faulting, and magmatism. It is difficult, however, to differentiate between competing interpretations of seismic velocity using these tomographic models alone. For example, in some areas the seismic velocities may be explained by either thin igneous crust or exhumed, serpentinized mantle. Distinguishing between these two interpretations is important as we explore the relationships between magmatism, faulting, and hydrothermal venting at ultraslow-spreading centers. We therefore improved our constraints on the shallow seismic velocity structure of the MCSC by modeling the amplitude of seismic refractions in the wide-angle data set. Synthetic seismograms were calculated with a finite-difference method for a range of models with different vertical velocity gradients. Small-scale features in the velocity models, such as steep velocity gradients and Moho boundaries, were explored systematically to best fit the real data. With this approach, we have improved our understanding of the compressional velocity structure of the MCSC along with the geological interpretations that are consistent with three seismic refraction profiles. Line P01 shows a variation in the thinness of lower seismic velocities along the axis, indicating two segment centers, while across-axis lines P02 and P03
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Fernández, Cristina; Pilar Callao, M; Larrechi, M Soledad
2013-12-15
The photodegradation process of three azo-dyes - Acid Orange 61, Acid Red 97 and Acid Brown 425 - was monitored simultaneously by ultraviolet-visible spectroscopy with diode array detector (UV-vis-DAD) and (1)H-nuclear magnetic resonance ((1)H-NMR). Multivariate curve resolution-alternating least squares (MCR-ALS) was applied to obtain the concentration and spectral profile of the chemical compounds involved in the process. The analysis of the H-NMR data suggests there are more intermediate compounds than those obtained with the UV-vis-DAD data. The fusion of UV-vis-DAD and the (1)H-NMR signal before the multivariate analysis provides better results than when only one of the two detector signals was used. It was concluded that three degradation products were present in the medium when the three azo-dyes had practically degraded. This study is the first application of UV-vis-DAD and (1)H-NMR spectroscopy data fusion in this field and illustrates its potential as a quick method for evaluating the evolution of the azo-dye photodegradation process. © 2013 Elsevier B.V. All rights reserved.
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Dynamics of poroelastocapillary rise
NASA Astrophysics Data System (ADS)
Nasouri, Babak; Elfring, Gwynn
2017-11-01
The surface-tension-driven rise of a liquid between two elastic sheets can result in their deformation or coalescence depending on their flexibility. When the sheets are poroelastic, the flexibility of the immersed parts of the sheets can change considerably thereby altering the dynamical behavior of the system. To better understand this phenomenon, we study the poroelastocapillary rise of a wetting liquid between poroelastic sheets. Using the lubrication theory and linear elasticity, we quantify the effects of the change in material properties of the wet sheets on the capillary rise and the equilibrium state of the system.
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Malik, Amrita; Tauler, Roma
2015-06-01
This work focuses on understanding the behaviour and patterns of three atmospheric pollutants namely, nitric oxide (NO), nitrogen dioxide (NO2), and ozone (O3) along with their mutual interactions in the atmosphere of Barcelona, North Spain. Hourly samples were collected for NO, NO2 and O3 from the same city location for three consecutive years (2010-2012). The study explores the seasonal, annual and weekday-weekend variations in their diurnal profiles along with the possible identification of their source and mutual interactions in the region. Multivariate Curve Resolution-Alternating Least Squares (MCR-ALS) was applied to the individual datasets of these pollutants, as well as to all of them simultaneously (augmented mode) to resolve the profiles related to their source and variation patterns in the atmosphere. The analysis of the individual datasets confirmed the source pattern variations in the concerned pollutant's profiles; and the resolved profiles for augmented datasets suggested for the mutual interaction of the pollutants along with their patterns variations, simultaneously. The study suggests vehicular pollution as the major source of atmospheric nitrogen oxides and presence of weekend ozone effect in the region. Copyright © 2015 Elsevier B.V. All rights reserved.
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CRISM/HiRISE Correlative Spectroscopy
NASA Astrophysics Data System (ADS)
Seelos, F. P.; Murchie, S. L.; McGovern, A.; Milazzo, M. P.; Herkenhoff, K. E.
2011-12-01
The Mars Reconnaissance Orbiter (MRO) Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) and High Resolution Imaging Science Experiment (HiRISE) are complementary investigations with high spectral resolution and broad wavelength coverage (CRISM ~20 m/pxl; ~400 - 4000 nm, 6.55 nm sampling) and high spatial resolution with broadband color capability (HiRISE ~25 cm/pxl; ~500, 700, 900 nm band centers, ~200-300 nm FWHM). Over the course of the MRO mission it has become apparent that spectral variations in the IR detected by CRISM (~1000 nm - 4000 nm) sometimes correlate spatially with visible and near infrared 3-band color variations observed by HiRISE. We have developed a data processing procedure that establishes a numerical mapping between HiRISE color and CRISM VNIR and IR spectral data and provides a statistical evaluation of the uncertainty in the mapping, with the objective of extrapolating CRISM-inferred mineralogy to the HiRISE spatial scale. The MRO mission profile, spacecraft capabilities, and science planning process emphasize coordinated observations - the simultaneous observation of a common target by multiple instruments. The commonalities of CRISM/HiRISE coordinated observations present a unique opportunity for tandem data analysis. Recent advances in the systematic processing of CRISM hyperspectral targeted observations account for gimbal-induced photometric variations and transform the data to a synthetic nadir acquisition geometry. The CRISM VNIR (~400 nm - 1000 nm) data can then be convolved to the HiRISE Infrared, Red, and Blue/Green (IRB) response functions to generate a compatible CRISM IRB product. Statistical evaluation of the CRISM/HiRISE spatial overlap region establishes a quantitative link between the data sets. IRB spectral similarity mapping for each HiRISE color spatial pixel with respect to the CRISM IRB product allows a given HiRISE pixel to be populated with information derived from the coordinated CRISM observation
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21 CFR 137.180 - Self-rising flour.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Self-rising flour. 137.180 Section 137.180 Food... Flours and Related Products § 137.180 Self-rising flour. (a) Self-rising flour, self-rising white flour, self-rising wheat flour, is an intimate mixture of flour, sodium bicarbonate, and one or more of the...
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Regional approaches in high-rise construction
NASA Astrophysics Data System (ADS)
Iconopisceva, O. G.; Proskurin, G. A.
2018-03-01
The evolutionary process of high-rise construction is in the article focus. The aim of the study was to create a retrospective matrix reflecting the tasks of the study such as: structuring the most iconic high-rise objects within historic boundaries. The study is based on contemporary experience of high-rise construction in different countries. The main directions and regional specifics in the field of high-rise construction as well as factors influencing the further evolution process are analyzed. The main changes in architectural stylistics, form-building, constructive solutions that focus on the principles of energy efficiency and bio positivity of "sustainable buildings", as well as the search for a new typology are noted. The most universal constructive methods and solutions that turned out to be particularly popular are generalized. The new typology of high-rises and individual approach to urban context are noted. The results of the study as a graphical scheme made it possible to represent the whole high-rise evolution. The new spatial forms of high-rises lead them to new role within the urban environments. Futuristic hyperscalable concepts take the autonomous urban space functions itself and demonstrate us how high-rises can replace multifunctional urban fabric, developing it inside their shells.
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ERIC Educational Resources Information Center
Lafo, Joseph; Robillard, Marc
2001-01-01
Explains how high-rise residence halls can provide high-level safety and security at colleges and universities. Boston University is used to illustrate high-rise security and fire protection issues. (GR)
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NASA Astrophysics Data System (ADS)
McEwen, A. S.; Eliason, E.; Gulick, V. C.; Spinoza, Y.; Beyer, R. A.; HiRISE Team
2010-12-01
The High Resolution Imaging Science Experiment (HiRISE) camera, orbiting Mars since 2006 on the Mars Reconnaissance Orbiter (MRO), has returned more than 17,000 large images with scales as small as 25 cm/pixel. From it’s beginning, the HiRISE team has followed “The People’s Camera” concept, with rapid release of useful images, explanations, and tools, and facilitating public image suggestions. The camera includes 14 CCDs, each read out into 2 data channels, so compressed images are returned from MRO as 28 long (up to 120,000 line) images that are 1024 pixels wide (or binned 2x2 to 512 pixels, etc.). This raw data is very difficult to use, especially for the public. At the HiRISE operations center the raw data are calibrated and processed into a series of B&W and color products, including browse images and JPEG2000-compressed images and tools to make it easy for everyone to explore these enormous images (see http://hirise.lpl.arizona.edu/). Automated pipelines do all of this processing, so we can keep up with the high data rate; images go directly to the format of the Planetary Data System (PDS). After students visually check each image product for errors, they are fully released just 1 month after receipt; captioned images (written by science team members) may be released sooner. These processed HiRISE images have been incorporated into tools such as Google Mars and World Wide Telescope for even greater accessibility. 51 Digital Terrain Models derived from HiRISE stereo pairs have been released, resulting in some spectacular flyover movies produced by members of the public and viewed up to 50,000 times according to YouTube. Public targeting began in 2007 via NASA Quest (http://marsoweb.nas.nasa.gov/HiRISE/quest/) and more than 200 images have been acquired, mostly by students and educators. At the beginning of 2010 we released HiWish (http://www.uahirise.org/hiwish/), opening HiRISE targeting to anyone in the world with Internet access, and already more
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HIGH RISE OR LOW RISE. A STUDY OF DECISION FACTORS IN RESIDENCE HALLS PLANNING.
ERIC Educational Resources Information Center
Educational Facilities Labs., Inc., New York, NY.
THE PURPOSE OF THIS REPORT IS TO SERVE COLLEGE OFFICIALS, HOUSING ADMINISTRATORS, PLANNING GROUPS AND ARCHITECTS BY FOCUSING ON THE DECISION FACTORS WHICH RELATE TO HIGH-RISE AND LOW-RISE STUDENT HOUSING. DECISION FACTORS INCLUDE--(1) LAND USE IMPLICATIONS, (2) SITE REQUIREMENTS--BUILDING CODES, SUB-SOIL CONSIDERATIONS, NATURAL TERRAIN,…
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NASA Astrophysics Data System (ADS)
Sanchez, J.; Mann, P.
2015-12-01
We have constructed a 1600-km-long transect from northern Honduras to northern Colombia that crosses northeastward-striking crustal blocks using a combination of offshore seismic data, gravity and magnetic data, well subsidence information, nearby outcrop information, and results from previous thermochronological, geochronological, geochemical and paleostress studies. The transect defines three major crustal and structural provinces: 1) Precambrian-Paleozoic, Chortis continental block whose northern edge is defined by the North America-Caribbean plate boundary. Events in this ~20-25-km-thick province include two major unconformities at the top of the Cretaceous and Eocene, associated southeast-dipping thrust faults related to collision of the Great Arc of the Caribbean (GAC) and Caribbean Large Igneous Province (CLIP) with the Chortis continental block. A third event is Eocene to recent subsidence and transtensional basins formed during the opening of the Cayman trough; 2) Late Cretaceous GAC and CLIP of oceanic arc and plateau origin, whose northern, deformed edge corresponds to the mapped Siuna belt of northern Nicaragua. This crustal province has a ~15-20-km-thick crust and is largely undeformed and extends across the Lower Nicaraguan Rise, Hess fault, to the southern limit of the Colombian basin where about 300 km of this province has been subducted beneath the accretionary wedge of the South Caribbean deformed belt of northwestern South America; and 3) Eocene to recent accretionary prism and intramontane basins on continental crust of northern South America, where Miocene accelerated exhumation and erosion of Paleogene and Cretaceous rocks reflect either shallow subduction of the CLIP or the Panama collisional event to the southwest.
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Stable plume rise in a shear layer.
Overcamp, Thomas J
2007-03-01
Solutions are given for plume rise assuming a power-law wind speed profile in a stably stratified layer for point and finite sources with initial vertical momentum and buoyancy. For a constant wind speed, these solutions simplify to the conventional plume rise equations in a stable atmosphere. In a shear layer, the point of maximum rise occurs further downwind and is slightly lower compared with the plume rise with a constant wind speed equal to the wind speed at the top of the stack. If the predictions with shear are compared with predictions for an equivalent average wind speed over the depth of the plume, the plume rise with shear is higher than plume rise with an equivalent average wind speed.
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Sun Radio Interferometer Space Experiment (SunRISE)
NASA Astrophysics Data System (ADS)
Kasper, Justin C.; SunRISE Team
2018-06-01
The Sun Radio Interferometer Space Experiment (SunRISE) is a NASA Heliophysics Explorer Mission of Opportunity currently in Phase A. SunRISE is a constellation of spacecraft flying in a 10-km diameter formation and operating as the first imaging radio interferometer in space. The purpose of SunRISE is to reveal critical aspects of solar energetic particle (SEP) acceleration at coronal mass ejections (CMEs) and transport into space by making the first spatially resolved observations of coherent Type II and III radio bursts produced by electrons accelerated at CMEs or released from flares. SunRISE will focus on solar Decametric-Hectometric (DH, 0.1 < f < 15 MHz) radio bursts that always are detected from space before major SEP events, but cannot be seen on Earth due to ionospheric absorption. This talk will describe SunRISE objectives and implementation. Presented on behalf of the entire SunRISE team.
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On Capillary Rise and Nucleation
ERIC Educational Resources Information Center
Prasad, R.
2008-01-01
A comparison of capillary rise and nucleation is presented. It is shown that both phenomena result from a balance between two competing energy factors: a volume energy and a surface energy. Such a comparison may help to introduce nucleation with a topic familiar to the students, capillary rise. (Contains 1 table and 3 figures.)
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Strategic advantages of high-rise construction
NASA Astrophysics Data System (ADS)
Yaskova, Natalya
2018-03-01
Traditional methods to assess the competitiveness of different types of real estate in the context of huge changes of new technological way of life don't provide building solutions that would be correct from a strategic perspective. There are many challenges due to changes in the consumers' behavior in the housing area. A multiplicity of life models, a variety of opportunities and priorities, traditions and new trends in construction should be assessed in terms of prospective benefits in the environment of the emerging new world order. At the same time, the mane discourse of high-rise construction mainly relates to its design features, technical innovations, and architectural accents. We need to clarify the criteria for economic evaluation of high-rise construction in order to provide decisions with clear and quantifiable contexts. The suggested approach to assessing the strategic advantage of high-rise construction and the prospects for capitalization of high-rise buildings poses new challenges for the economy to identify adequate quantitative assessment methods of the high-rise buildings economic efficiency, taking into account all stages of their life cycle.
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Choices for a Rising Generation
ERIC Educational Resources Information Center
Obama, Barack
2008-01-01
This article presents an essay by the 2008 Democratic Party Presidential Nominee. This essay focuses on the role of the rising generation in bringing about real change in America. The author contends that, at this historic moment, Americans must ask their rising generation to serve their country as Americans always have--by working on a political…
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21 CFR 137.185 - Enriched self-rising flour.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Enriched self-rising flour. 137.185 Section 137... Cereal Flours and Related Products § 137.185 Enriched self-rising flour. Enriched self-rising flour... carbon dioxide evolved under ordinary conditions of use of the enriched self-rising flour is not less...
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21 CFR 137.185 - Enriched self-rising flour.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Enriched self-rising flour. 137.185 Section 137... Cereal Flours and Related Products § 137.185 Enriched self-rising flour. Enriched self-rising flour... carbon dioxide evolved under ordinary conditions of use of the enriched self-rising flour is not less...
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21 CFR 137.185 - Enriched self-rising flour.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Enriched self-rising flour. 137.185 Section 137... Cereal Flours and Related Products § 137.185 Enriched self-rising flour. Enriched self-rising flour... carbon dioxide evolved under ordinary conditions of use of the enriched self-rising flour is not less...
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21 CFR 137.185 - Enriched self-rising flour.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Enriched self-rising flour. 137.185 Section 137... Cereal Flours and Related Products § 137.185 Enriched self-rising flour. Enriched self-rising flour... carbon dioxide evolved under ordinary conditions of use of the enriched self-rising flour is not less...
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Thorpe, Kenneth E
2006-11-01
To examine the factors responsible for the rise in health- care spending in the United States over the past 15 years. Nationally representative survey data from 1987 and 2003 were used to examine the top medical conditions accounting for the rise in spending. I also estimate how much of the rise is traced to rising treated disease prevalence and rising spending per case. The study finds most of the rise in spending is linked to rising rates of treated disease prevalence. The rise in prevalence is associated with the doubling of obesity in the US and changes in clinical thresholds for treating asymptomatic patients with certain cardiovascular risk factors. Most of the policy solutions offered in the US to slow the growth in spending do not address the fundamental factors accounting for spending growth. More aggressive efforts for slowing the growth in obesity among adults and children should be centre-stage in the efforts to slow the rise in health-care spending.
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Socioecological Aspects of High-rise Construction
NASA Astrophysics Data System (ADS)
Eichner, Michael; Ivanova, Zinaida
2018-03-01
In this article, the authors consider the socioecological problems that arise in the construction and operation of high-rise buildings. They study different points of view on high-rise construction and note that the approaches to this problem are very different. They also analyse projects of modern architects and which attempts are made to overcome negative impacts on nature and mankind. The article contains materials of sociological research, confirming the ambivalent attitude of urban population to high-rise buildings. In addition, one of the author's sociological survey reveals the level of environmental preparedness of the university students, studying in the field of "Construction of unique buildings and structures", raising the question of how future specialists are ready to take into account socioecological problems. Conclusion of the authors: the construction of high-rise buildings is associated with huge social and environmental risks, negative impact on the biosphere and human health. This requires deepened skills about sustainable design methods and environmental friendly construction technologies of future specialists. Professor M. Eichner presents in the article his case study project results on implementation of holistic eco-sustainable construction principles for mixed-use high-rise building in the metropolis of Cairo.
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NASA Astrophysics Data System (ADS)
Scheuermann, P. P.; Seyfried, W. E.
2018-05-01
The subsurface pressure-temperature conditions at the Piccard hydrothermal field are constrained using the Si-Cl geothermobarometer. Ol-Mgt and Opx-Mgt are proposed as assemblages that buffer H2(aq) at Piccard.
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Volcanic rocks cored on hess rise, Western Pacific Ocean
Vallier, T.L.; Windom, K.E.; Seifert, K.E.; Thiede, Jorn
1980-01-01
Large aseismic rises and plateaus in the western Pacific include the Ontong-Java Plateau, Magellan Rise, Shatsky Rise, Mid-Pacific Mountains, and Hess Rise. These are relatively old features that rise above surrounding sea floors as bathymetric highs. Thick sequences of carbonate sediments overlie, what are believed to be, Upper Jurassic and Lower Cretaceous volcanic pedestals. We discuss here petrological and tectonic implications of data from volcanic rocks cored on Hess Rise. The data suggest that Hess Rise originated at a spreading centre in the late early Cretaceous (Aptian-Albian stages). Subsequent off-ridge volcanism in the late Albian-early Cenomanian stages built a large archipelago of oceanic islands and seamounts composed, at least in part, of alkalic rocks. The volcanic platform subsided during its northward passage through the mid-Cretaceousequatorial zone. Faulting and uplift, and possibly volcanism, occurred in the latest Cretaceous (Campanian-Maastrichtian stages). Since then, Hess Rise continued its northward movement and subsidence. Volcanic rocks from holes drilled on Hess Rise during IPOD Leg 62 (Fig. 1) are briefly described here and we relate the petrological data to the origin and evolution of that rise. These are the first volcanic rocks reported from Hess Rise. ?? 1980 Nature Publishing Group.
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Wagner, Tristan; Wegner, Carl-Eric; Kahnt, Jörg; Ermler, Ulrich; Shima, Seigo
2017-05-30
The phylogenetically diverse family of methanogenic archaea universally use methyl-coenzyme M reductase (MCR) for catalyzing the final methane-forming reaction step of the methanogenic energy metabolism. Some methanogens of the orders Methanobacteriales and Methanococcales contain two isoenzymes. Comprehensive phylogenetic analyses on the basis of all three subunits grouped MCRs from Methanobacteriales, Methanococcales and Methanopyrales into three distinct types: (1) MCRs from Methanobacteriales, (2) MCRs from Methanobacteriales and Methanococcales and (3) MCRs from Methanococcales. The first and second types contain MCR isoenzyme I and II from Methanothermobacter marburgensis , respectively; therefore, they were designated as MCR type I and type II and accordingly, the third one was designated as MCR type III. For comparison with the known MCR type I and type II structures, we determined the structure of MCR type III from Methanotorris formicicus and Methanothermococcus thermolithotrophicus As predicted, the three MCR types revealed highly similar overall structures and a virtually identical active site architecture reflecting the chemically challenging mechanism of methane formation. Pronounced differences were found at the protein surface with respect to loop geometries and electrostatic properties, which also involve the entrance of the active site funnel. In addition, the C-terminal end of the γ-subunit is prolonged by an extra helix after helix γ8 in MCR type II and type III, which is, however, differently arranged in the two MCR types. MCR types I, II and III share most of the post-translational modifications which appear to fine-tune the enzymatic catalysis. Interestingly, MCR type III lacks the methyl-cysteine but possesses in subunit α of M. formicicus a 6-hydroxy-tryptophan, which has been, so far, only found in the α-amanitin toxin peptide but not in proteins. IMPORTANCE Methyl-coenzyme M reductase (MCR) represents a prime target for the mitigation
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2011-03-19
The full moon is seen as it rises near the National Mall, Saturday, March 19, 2011, in Washington. The full moon tonight is called a "Super Moon" since it is at its closest to Earth. Photo Credit: (NASA/Paul E. Alers)
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Parastar, Hadi; Akvan, Nadia
2014-03-13
In the present contribution, a new combination of multivariate curve resolution-correlation optimized warping (MCR-COW) with trilinear parallel factor analysis (PARAFAC) is developed to exploit second-order advantage in complex chromatographic measurements. In MCR-COW, the complexity of the chromatographic data is reduced by arranging the data in a column-wise augmented matrix, analyzing using MCR bilinear model and aligning the resolved elution profiles using COW in a component-wise manner. The aligned chromatographic data is then decomposed using trilinear model of PARAFAC in order to exploit pure chromatographic and spectroscopic information. The performance of this strategy is evaluated using simulated and real high-performance liquid chromatography-diode array detection (HPLC-DAD) datasets. The obtained results showed that the MCR-COW can efficiently correct elution time shifts of target compounds that are completely overlapped by coeluted interferences in complex chromatographic data. In addition, the PARAFAC analysis of aligned chromatographic data has the advantage of unique decomposition of overlapped chromatographic peaks to identify and quantify the target compounds in the presence of interferences. Finally, to confirm the reliability of the proposed strategy, the performance of the MCR-COW-PARAFAC is compared with the frequently used methods of PARAFAC, COW-PARAFAC, multivariate curve resolution-alternating least squares (MCR-ALS), and MCR-COW-MCR. In general, in most of the cases the MCR-COW-PARAFAC showed an improvement in terms of lack of fit (LOF), relative error (RE) and spectral correlation coefficients in comparison to the PARAFAC, COW-PARAFAC, MCR-ALS and MCR-COW-MCR results. Copyright © 2014 Elsevier B.V. All rights reserved.
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Amplitude- and rise-time-compensated filters
Nowlin, Charles H.
1984-01-01
An amplitude-compensated rise-time-compensated filter for a pulse time-of-occurrence (TOOC) measurement system is disclosed. The filter converts an input pulse, having the characteristics of random amplitudes and random, non-zero rise times, to a bipolar output pulse wherein the output pulse has a zero-crossing time that is independent of the rise time and amplitude of the input pulse. The filter differentiates the input pulse, along the linear leading edge of the input pulse, and subtracts therefrom a pulse fractionally proportional to the input pulse. The filter of the present invention can use discrete circuit components and avoids the use of delay lines.
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Why did employee health insurance contributions rise?
Gruber, Jonathan; McKnight, Robin
2003-11-01
We explore the causes of the dramatic rise in employee contributions to health insurance over the past two decades. In 1982, 44% of those who were covered by their employer-provided health insurance had their costs fully financed by their employer, but by 1998 this had fallen to 28%. We discuss the theory of why employers might shift premiums to their employees, and empirically model the role of four factors suggested by the theory. We find that there was a large impact of falling tax rates, rising eligibility for insurance through the Medicaid system, rising medical costs, and increased managed care penetration. Overall, this set of factors can explain more than one-half of the rise in employee premiums over the 1982-1996 period.
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Monago-Maraña, Olga; Pérez, Rocío L; Escandar, Graciela M; Muñoz de la Peña, Arsenio; Galeano-Díaz, Teresa
2016-11-02
This work presents a strategy for quantitating polycyclic aromatic hydrocarbons (PAHs) in smoked paprika samples. For this, a liquid chromatographic method with fluorimetric detection (HPLC-FLD) was optimized. To resolve some interference co-eluting with the target analytes, the second-order multivariate curve resolution-alternating least-squares (MCR-ALS) algorithm has been employed combined with this liquid chromatographic method. Among the eight PAHs quantified (fluorene, phenanthrene, anthracene, pyrene, chrysene, benzo[a]anthracene, benzo[b]fluoranthene, and benzo[a]pyrene) by HPLC-FLD, only in the case of fluorene, pyrene, and benzo[b]fluoranthene was it necessary to apply the second-order algorithm for their resolution. Limits of detection and quantitation were between 0.015 and 0.45 mg/kg and between 0.15 and 1.5 mg/kg, respectively. Good recovery results (>80%) for paprika were obtained via the complete extraction procedure, consisting of an extraction from the matrix and the cleanup of the extract by means of silica cartridges. Higher concentrations of chrysene, benzo[a]anthracene, benzo[b]fluoranthene, and benzo[a]pyrene were found in the paprika samples, with respect to the maximal amounts allowed for other spices that are under European Regulation (EU) N° 2015/1933.
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Disposal of Kitchen Waste from High Rise Apartment
NASA Astrophysics Data System (ADS)
Ori, Kirki; Bharti, Ajay; Kumar, Sunil
2017-09-01
The high rise building has numbers of floor and rooms having variety of users or tenants for residential purposes. The huge quantities of heterogenous mixtures of domestic food waste are generated from every floor of the high rise residential buildings. Disposal of wet and biodegradable domestic kitchen waste from high rise buildings are more expensive in regards of collection and vertical transportation. This work is intended to address the technique to dispose of the wet organic food waste from the high rise buildings or multistory building at generation point with the advantage of gravity and vermicomposting technique. This innovative effort for collection and disposal of wet organic solid waste from high rise apartment is more economical and hygienic in comparison with present system of disposal.
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Cai, Jie; Lv, Peng; Guan, Qingfeng; Xu, Xiaojing; Lu, Jinzhong; Wang, Zhiping; Han, Zhiyong
2016-11-30
Microstructural modifications of a thermally sprayed MCrAlY bond coat subjected to high-current pulsed electron beam (HCPEB) and their relationships with thermal cycling behavior of thermal barrier coatings (TBCs) were investigated. Microstructural observations revealed that the rough surface of air plasma spraying (APS) samples was significantly remelted and replaced by many interconnected bulged nodules after HCPEB irradiation. Meanwhile, the parallel columnar grains with growth direction perpendicular to the coating surface were observed inside these bulged nodules. Substantial Y-rich Al 2 O 3 bubbles and varieties of nanocrystallines were distributed evenly on the top of the modified layer. A physical model was proposed to describe the evaporation-condensation mechanism taking place at the irradiated surface for generating such surface morphologies. The results of thermal cycling test showed that HCPEB-TBCs presented higher thermal cycling resistance, the spalling area of which after 200 cycles accounted for only 1% of its total area, while it was about 34% for APS-TBCs. The resulting failure mode, i.e., in particular, a mixed delamination crack path, was shown and discussed. The irradiated effects including compact remelted surface, abundant nanoparticles, refined columnar grains, Y-rich alumina bubbles, and deformation structures contributed to the formation of a stable, continuous, slow-growing, and uniform thermally grown oxide with strong adherent ability. It appeared to be responsible for releasing stress and changing the cracking paths, and ultimately greatly improving the thermal cycling behavior of HCPEB-TBCs.
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Trend analysis of modern high-rise construction
NASA Astrophysics Data System (ADS)
Radushinsky, Dmitry; Gubankov, Andrey; Mottaeva, Asiiat
2018-03-01
The article reviews the main trends of modern high-rise construction considered a number of architectural, engineering and technological, economic and image factors that have influenced the intensification of construction of high-rise buildings in the 21st century. The key factors of modern high-rise construction are identified, which are associated with an attractive image component for businessmen and politicians, with the ability to translate current views on architecture and innovations in construction technologies and the lobbying of relevant structures, as well as the opportunity to serve as an effective driver in the development of a complex of national economy sectors with the achievement of a multiplicative effect. The estimation of the priority nature of participation of foreign architectural bureaus in the design of super-high buildings in Russia at the present stage is given. The issue of economic expediency of construction of high-rise buildings, including those with only a residential function, has been investigated. The connection between the construction of skyscrapers as an important component of the image of cities in the marketing of places and territories, the connection of the availability of a high-rise center, the City, with the possibilities of attracting a "creative class" and the features of creating a large working space for specialists on the basis of territorial proximity and density of high-rise buildings.
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Cenozoic seismic stratigraphy of the SW Bermuda Rise
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mountain, G.S.; Driscoll, N.W.; Miller, K.G.
1985-01-01
The seismic Horizon A-Complex (Tucholke, 1979) readily explains reflector patterns observed along the western third of the Bermuda Rise; farther east, basement is much more rugged and gravity flows shed from local topographic highs complicate the stratigraphy. Distal turbidites on the southwestern Bermuda Rise onlap reflector A* from the west, suggesting early Paleocene mass wasting of the North American margin. Locally erosive bottom currents cut into the middle Eocene section of the SW Bermuda Rise; these northward flowing currents preceded those that formed reflector Au along the North American margin near the Eocene-Oligocene boundary. Southward flowing currents swift enough tomore » erode the sea floor and to form reflector Au did not reach as far east as the SW Bermuda Rise. Instead, the main effect of these Au currents was to pirate sediment into contour-following geostrophic flows along the North American margin and to deprive the deep basin and the Bermuda Rise of sediment transported down-slope. Consequently, post-Eocene sediments away from the margin are fine-grained muds. Deposition of these muds on the SW Bermuda Rise was controlled by northward flowing bottom currents. The modern Hatteras Abyssal Plain developed in the late Neogene as turbidites once again onlapped the SW Bermuda Rise. Today, these deposits extend farthest east in fracture zone valleys and in the swales between sediment waves. Northward flowing currents continue at present to affect sediment distribution patterns along the western edge of the Bermuda Rise.« less
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Cazenave, Anny; Llovel, William
2010-01-01
Measuring sea level change and understanding its causes has considerably improved in the recent years, essentially because new in situ and remote sensing observations have become available. Here we report on most recent results on contemporary sea level rise. We first present sea level observations from tide gauges over the twentieth century and from satellite altimetry since the early 1990s. We next discuss the most recent progress made in quantifying the processes causing sea level change on timescales ranging from years to decades, i.e., thermal expansion of the oceans, land ice mass loss, and land water-storage change. We show that for the 1993-2007 time span, the sum of climate-related contributions (2.85 +/- 0.35 mm year(-1)) is only slightly less than altimetry-based sea level rise (3.3 +/- 0.4 mm year(-1)): approximately 30% of the observed rate of rise is due to ocean thermal expansion and approximately 55% results from land ice melt. Recent acceleration in glacier melting and ice mass loss from the ice sheets increases the latter contribution up to 80% for the past five years. We also review the main causes of regional variability in sea level trends: The dominant contribution results from nonuniform changes in ocean thermal expansion.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Gomez-Vidal, Judith C.
Corrosion evaluations of Incoloy 800 H (In800H) and stainless steel AISI 310 (310SS), in bare and coated conditions, were performed in 34.42 wt% NaCl – 55.47 wt% KCl at 700 °C in a nitrogen atmosphere. This NaCl–KCl composition has a melting point of 657 °C, which makes it suitable for latent-heat thermal energy storage in concentrating solar power applications. Several nickel-based MCrAlX coatings were tested, where M = Ni and/or Co and X = Y, Ta, Hf, and/or Si. Electrochemical testing was carried out to determine corrosion rates. The bare In800H and 310SS alloys corroded rapidly (~2500 and 4500 µm/yr,more » respectively, assuming uniform corrosion). Concentrating solar power plants need containment materials with a lifetime of at least 30 years; thus, these corrosion rates are excessive. Corrosion mitigation approaches are being investigated to obtain degradation on the order of 20 µm/yr or lower. The lowest corrosion rate of 190 µm/yr was obtained for atmospheric plasma spray NiCoCrAlY coatings pre-oxidized in air at 900 °C for 24 h with a heating/cooling rate of 0.5 °C/min. Metallographic characterization of the corroded surfaces showed that the formation of a uniform thin alumina scale before exposure to the molten chloride system considerably reduced the corrosion of the alloy. However, the rates of corrosion determined herein are considerable, highlighting the relevance of testing materials durability in solar power applications.« less
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Gomez-Vidal, Judith C.
2017-09-18
Corrosion evaluations of Incoloy 800 H (In800H) and stainless steel AISI 310 (310SS), in bare and coated conditions, were performed in 34.42 wt% NaCl – 55.47 wt% KCl at 700 °C in a nitrogen atmosphere. This NaCl–KCl composition has a melting point of 657 °C, which makes it suitable for latent-heat thermal energy storage in concentrating solar power applications. Several nickel-based MCrAlX coatings were tested, where M = Ni and/or Co and X = Y, Ta, Hf, and/or Si. Electrochemical testing was carried out to determine corrosion rates. The bare In800H and 310SS alloys corroded rapidly (~2500 and 4500 µm/yr,more » respectively, assuming uniform corrosion). Concentrating solar power plants need containment materials with a lifetime of at least 30 years; thus, these corrosion rates are excessive. Corrosion mitigation approaches are being investigated to obtain degradation on the order of 20 µm/yr or lower. The lowest corrosion rate of 190 µm/yr was obtained for atmospheric plasma spray NiCoCrAlY coatings pre-oxidized in air at 900 °C for 24 h with a heating/cooling rate of 0.5 °C/min. Metallographic characterization of the corroded surfaces showed that the formation of a uniform thin alumina scale before exposure to the molten chloride system considerably reduced the corrosion of the alloy. However, the rates of corrosion determined herein are considerable, highlighting the relevance of testing materials durability in solar power applications.« less
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Montero Ruiz, E; Rebollar Merino, Á; Melgar Molero, V; Barbero Allende, J M; Culebras López, A; López Álvarez, J
2014-01-01
Within-hospital medical consultations and referrals (MCR) have many problems, among them are those related to the oral and written transmission of information. Our aim is to analyze problems in the transmission of information related to MCR, and possible differences between medical (MS) and surgical (SS) services. A prospective, observational study was conducted on the MCR requested to Internal Medicine Service over an 8 month period. The following variables were collected: age, sex, the requester, MCR type, type of admission, comorbidity, hospital stay and mortality, length of MCR, the number of physicians responsible for the patient requesting service during the MCR, MCR repeats, information on the request, available medical records, verbal contact, conflict between doctors, and medical information in the discharge summary. Of the total 215 MCR received, 66 (30.7%) were requested by MS, and 149 (69.3%) per SS. MCR duration was 3 days (standard deviation [SD] 4.8. The number of doctors responsible was 1.7 (SD 1.1), with, Repeats 43 (20%) and Urgent 14 (6.5%). Minimum information on the request, 6 (9.1%) MS and 21 (27.5%) SS. Low availability of medical record, 2 (3%) MS and 50 (33.6%) SS. No verbal contact, 33 (15.4%). Conflict between doctors 13 (6%). Information acceptably good in MCR urgent request 100% MS, and 80% SS. Two out of three MCR were without reference to the discharge report. There are significant losses in the transmission of information during the process of the MCR, which is higher in surgical than in medical departments. Copyright © 2013 SECA. Published by Elsevier Espana. All rights reserved.
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21 CFR 137.290 - Self-rising yellow corn meal.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Self-rising yellow corn meal. 137.290 Section 137... Cereal Flours and Related Products § 137.290 Self-rising yellow corn meal. Self-rising yellow corn meal conforms to the definition and standard of identity prescribed by § 137.270 for self-rising white corn meal...
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21 CFR 137.290 - Self-rising yellow corn meal.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Self-rising yellow corn meal. 137.290 Section 137... Cereal Flours and Related Products § 137.290 Self-rising yellow corn meal. Self-rising yellow corn meal conforms to the definition and standard of identity prescribed by § 137.270 for self-rising white corn meal...
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Sea level rise with warming above 2 degree
NASA Astrophysics Data System (ADS)
Jevrejeva, Svetlana; Jackson, Luke; Riva, Riccardo; Grinsted, Aslak; Moore, John
2017-04-01
Holding the increase in the global average temperature to below 2 °C above pre-industrial levels, and pursuing efforts to limit the temperature increase to 1.5 °C, has been agreed by the representatives of the 196 parties of United Nations, as an appropriate threshold beyond which climate change risks become unacceptably high. Sea level rise is one of the most damaging aspects of warming climate for the more than 600 million people living in low-elevation coastal areas less than 10 meters above sea level. Fragile coastal ecosystems and increasing concentrations of population and economic activity in coastal areas, are reasons why future sea level rise is one of the most damaging aspects of the warming climate. Furthermore, sea level is set to continue to rise for centuries after greenhouse gas emissions concentrations are stabilised due to system inertia and feedback time scales. Impact, risk, adaptation policies and long-term decision making in coastal areas depend on regional and local sea level rise projections and local projections can differ substantially from the global one. Here we provide probabilistic sea level rise projections for the global coastline with warming above the 2 degree goal. A warming of 2°C makes global ocean rise on average by 20 cm, but more than 90% of coastal areas will experience greater rises, 40 cm along the Atlantic coast of North America and Norway, due to ocean dynamics. If warming continues above 2°C, then by 2100 sea level will rise with speeds unprecedented throughout human civilization, reaching 0.9 m (median), and 80% of the global coastline will exceed the global ocean sea level rise upper 95% confidence limit of 1.8 m. Coastal communities of rapidly expanding cities in the developing world, small island states, and vulnerable tropical coastal ecosystems will have a very limited time after mid-century to adapt to sea level rises.
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Bottlenecks aggravate rising construction costs
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
2008-05-15
Rising demand for power in developing countries combined with concerns about carbon emissions from coal-fired power plants in developed countries have created a bonanza for carbon-light technologies, including nuclear, renewables and natural gas plants. This, in turn, has put upward pressure on the price of natural gas in key markets while resulting in shortages in critical components for building renewables and nuclear reactors. Globalization of the power industry means that pressures in one segment or one region translate into shortages and rising prices everywhere else.
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ERIC Educational Resources Information Center
USA Today, 1981
1981-01-01
Focuses on ways in which parents of school-age children can offset the rising costs of college, including encouraging students to get summer and part-time jobs, putting savings toward students' education in accounts in students' names to save taxes, investigating cooperative work/education plans, and investing in mutual funds. (DB)
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2017-12-08
Small valley glacier exiting the Devon Island Ice Cap in Canada. To learn about the contributions of glaciers to sea level rise, visit: www.nasa.gov/topics/earth/features/glacier-sea-rise.html Credit: Alex Gardner, Clark University NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram
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Rise and Shock: Optimal Defibrillator Placement in a High-rise Building.
Chan, Timothy C Y
2017-01-01
Out-of-hospital cardiac arrests (OHCA) in high-rise buildings experience lower survival and longer delays until paramedic arrival. Use of publicly accessible automated external defibrillators (AED) can improve survival, but "vertical" placement has not been studied. We aim to determine whether elevator-based or lobby-based AED placement results in shorter vertical distance travelled ("response distance") to OHCAs in a high-rise building. We developed a model of a single-elevator, n-floor high-rise building. We calculated and compared the average distance from AED to floor of arrest for the two AED locations. We modeled OHCA occurrences using floor-specific Poisson processes, the risk of OHCA on the ground floor (λ 1 ) and the risk on any above-ground floor (λ). The elevator was modeled with an override function enabling direct travel to the target floor. The elevator location upon override was modeled as a discrete uniform random variable. Calculations used the laws of probability. Elevator-based AED placement had shorter average response distance if the number of floors (n) in the building exceeded three quarters of the ratio of ground-floor OHCA risk to above-ground floor risk (λ 1 /λ) plus one half (n ≥ 3λ 1 /4λ + 0.5). Otherwise, a lobby-based AED had shorter average response distance. If OHCA risk on each floor was equal, an elevator-based AED had shorter average response distance. Elevator-based AEDs travel less vertical distance to OHCAs in tall buildings or those with uniform vertical risk, while lobby-based AEDs travel less vertical distance in buildings with substantial lobby, underground, and nearby street-level traffic and OHCA risk.
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NASA Astrophysics Data System (ADS)
Cross, Rod
2018-03-01
Experimental and theoretical results are presented concerning the rise of a spinning egg. It was found that an egg rises quickly while it is sliding and then more slowly when it starts rolling. The angular momentum of the egg projected in the XZ plane changed in the same direction as the friction torque, as expected, by rotating away from the vertical Z axis. The latter result does not explain the rise. However, an even larger effect arises from the Y component of the angular momentum vector. As the egg rises, the egg rotates about the Y axis, an effect that is closely analogous to rotation of the egg about the Z axis. Both effects can be described in terms of precession about the respective axes. Steady precession about the Z axis arises from the normal reaction force in the Z direction, while precession about the Y axis arises from the friction force in the Y direction. Precession about the Z axis ceases if the normal reaction force decreases to zero, and precession about the Y axis ceases if the friction force decreases to zero.
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Rising Sea Levels: Truth or Scare?
ERIC Educational Resources Information Center
Peacock, Alan
2007-01-01
When "ITV News" ran an item that shocked the author, about rising sea levels that will have caused the entire evacuation of the islands by the end of this year, he began to wonder whether the Pacific Ocean is really rising as fast as this. The media reporting of such things can be a double-edged sword. On the one hand, it brought to the author's…
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The social values at risk from sea-level rise
DOE Office of Scientific and Technical Information (OSTI.GOV)
Graham, Sonia, E-mail: sonia.graham@unimelb.edu.au; Barnett, Jon, E-mail: jbarn@unimelb.edu.au; Fincher, Ruth, E-mail: r.fincher@unimelb.edu.au
Analysis of the risks of sea-level rise favours conventionally measured metrics such as the area of land that may be subsumed, the numbers of properties at risk, and the capital values of assets at risk. Despite this, it is clear that there exist many less material but no less important values at risk from sea-level rise. This paper re-theorises these multifarious social values at risk from sea-level rise, by explaining their diverse nature, and grounding them in the everyday practices of people living in coastal places. It is informed by a review and analysis of research on social values frommore » within the fields of social impact assessment, human geography, psychology, decision analysis, and climate change adaptation. From this we propose that it is the ‘lived values’ of coastal places that are most at risk from sea-level rise. We then offer a framework that groups these lived values into five types: those that are physiological in nature, and those that relate to issues of security, belonging, esteem, and self-actualisation. This framework of lived values at risk from sea-level rise can guide empirical research investigating the social impacts of sea-level rise, as well as the impacts of actions to adapt to sea-level rise. It also offers a basis for identifying the distribution of related social outcomes across populations exposed to sea-level rise or sea-level rise policies.« less
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2017-12-08
Summit camp on top of the Austfonna Ice Cap in Svalbard (Norwegian Arctic). To learn about the contributions of glaciers to sea level rise, visit: www.nasa.gov/topics/earth/features/glacier-sea-rise.html Credit: Thorben Dunse, University of Oslo NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram
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Adapting to Rising Sea Level: A Florida Perspective
NASA Astrophysics Data System (ADS)
Parkinson, Randall W.
2009-07-01
Global climate change and concomitant rising sea level will have a profound impact on Florida's coastal and marine systems. Sea-level rise will increase erosion of beaches, cause saltwater intrusion into water supplies, inundate coastal marshes and other important habitats, and make coastal property more vulnerable to erosion and flooding. Yet most coastal areas are currently managed under the premise that sea-level rise is not significant and the shorelines are static or can be fixed in place by engineering structures. The new reality of sea-level rise and extreme weather due to climate change requires a new style of planning and management to protect resources and reduce risk to humans. Scientists must: (1) assess existing coastal vulnerability to address short term management issues and (2) model future landscape change and develop sustainable plans to address long term planning and management issues. Furthermore, this information must be effectively transferred to planners, managers, and elected officials to ensure their decisions are based upon the best available information. While there is still some uncertainty regarding the details of rising sea level and climate change, development decisions are being made today which commit public and private investment in real estate and associated infrastructure. With a design life of 30 yrs to 75 yrs or more, many of these investments are on a collision course with rising sea level and the resulting impacts will be significant. In the near term, the utilization of engineering structures may be required, but these are not sustainable and must ultimately yield to "managed withdrawal" programs if higher sea-level elevations or rates of rise are forthcoming. As an initial step towards successful adaptation, coastal management and planning documents (i.e., comprehensive plans) must be revised to include reference to climate change and rising sea-level.
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High-Rise Housing for Low-Income Families.
ERIC Educational Resources Information Center
Fuerst, J. S.; Petty, Roy
1991-01-01
Discusses successes and failures of subsidized housing in urban areas and the relationship between architectural environment and quality of life, particularly as regards high-rise buildings. Given that some high-rise projects are successful, most should be maintained because of the scarcity of low-income housing. (DM)
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Updating Maryland's sea-level rise projections
Boesch, Donald F.; Atkinson, Larry P.; Boicourt, William C.; Boon, John D.; Cahoon, Donald R.; Dalrymple, Robert A.; Ezer, Tal; Horton, Benjamin P.; Johnson, Zoe P.; Kopp, Robert E.; Li, Ming; Moss, Richard H.; Parris, Adam; Sommerfield, Christopher K.
2013-01-01
With its 3,100 miles of tidal shoreline and low-lying rural and urban lands, “The Free State” is one of the most vulnerable to sea-level rise. Historically, Marylanders have long had to contend with rising water levels along its Chesapeake Bay and Atlantic Ocean and coastal bay shores. Shorelines eroded and low-relief lands and islands, some previously inhabited, were inundated. Prior to the 20th century, this was largely due to the slow sinking of the land since Earth’s crust is still adjusting to the melting of large masses of ice following the last glacial period. Over the 20th century, however, the rate of rise of the average level of tidal waters with respect to land, or relative sea-level rise, has increased, at least partially as a result of global warming. Moreover, the scientific evidence is compelling that Earth’s climate will continue to warm and its oceans will rise even more rapidly. Recognizing the scientific consensus around global climate change, the contribution of human activities to it, and the vulnerability of Maryland’s people, property, public investments, and natural resources, Governor Martin O’Malley established the Maryland Commission on Climate Change on April 20, 2007. The Commission produced a Plan of Action that included a comprehensive climate change impact assessment, a greenhouse gas reduction strategy, and strategies for reducing Maryland’s vulnerability to climate change. The Plan has led to landmark legislation to reduce the state’s greenhouse gas emissions and a variety of state policies designed to reduce energy consumption and promote adaptation to climate change.
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The advisability of high-rise construction in the city
NASA Astrophysics Data System (ADS)
Sergievskaya, Natalia; Pokrovskaya, Tatyana; Vorontsova, Natalya
2018-03-01
In this article there discusses the question of advisability high-rise construction, the reasons for its use, both positive and negative sides of it. On the one hand, a number of authors believe that it is difficult to avoid high-rise construction due to the limited areas in very large cities. On the other hand, a number of other authors draw attention to the problems associated with high-rise construction. The author of the article analyses examples of high-rise construction in several countries (UAE, Dubai "Burj Khalifa"; Japan "Tokyo Sky Tree"; United States of America, "Willis Tower"; Russia "Federation Tower") and proves the advisability of high-rise construction in the city.
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Leasing instruments of high-rise construction financing
NASA Astrophysics Data System (ADS)
Aleksandrova, Olga; Ivleva, Elena; Sukhacheva, Viktoria; Rumyantseva, Anna
2018-03-01
The leasing sector of the business economics is expanding. Leasing instruments for high-rise construction financing allow to determine the best business behaviour in the leasing economy sector, not only in the sphere of transactions with equipment and vehicles. Investments in high-rise construction have a multiplicative effect. It initiates an active search and leasing instruments use in the economic behaviour of construction organizations. The study of the high-rise construction sector in the structure of the leasing market participants significantly expands the leasing system framework. The scheme of internal and external leasing process factors influence on the result formation in the leasing sector of economy is offered.
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Correcting spacecraft jitter in HiRISE images
Sutton, S. S.; Boyd, A.K.; Kirk, Randolph L.; Cook, Debbie; Backer, Jean; Fennema, A.; Heyd, R.; McEwen, A.S.; Mirchandani, S.D.; Wu, B.; Di, K.; Oberst, J.; Karachevtseva, I.
2017-01-01
Mechanical oscillations or vibrations on spacecraft, also called pointing jitter, cause geometric distortions and/or smear in high resolution digital images acquired from orbit. Geometric distortion is especially a problem with pushbroom type sensors, such as the High Resolution Imaging Science Experiment (HiRISE) instrument on board the Mars Reconnaissance Orbiter (MRO). Geometric distortions occur at a range of frequencies that may not be obvious in the image products, but can cause problems with stereo image correlation in the production of digital elevation models, and in measuring surface changes over time in orthorectified images. The HiRISE focal plane comprises a staggered array of fourteen charge-coupled devices (CCDs) with pixel IFOV of 1 microradian. The high spatial resolution of HiRISE makes it both sensitive to, and an excellent recorder of jitter. We present an algorithm using Fourier analysis to resolve the jitter function for a HiRISE image that is then used to update instrument pointing information to remove geometric distortions from the image. Implementation of the jitter analysis and image correction is performed on selected HiRISE images. Resulting corrected images and updated pointing information are made available to the public. Results show marked reduction of geometric distortions. This work has applications to similar cameras operating now, and to the design of future instruments (such as the Europa Imaging System).
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2017-12-08
Aerial view of the Sverdrup Glacier, a river of ice that flows from the interior of the Devon Island Ice Cap (Canada) into the ocean. To learn about the contributions of glaciers to sea level rise, visit: www.nasa.gov/topics/earth/features/glacier-sea-rise.html Credit: Alex Gardner, Clark University NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram
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2017-12-08
Melt water ponded at surface in the accumulation zone of Columbia Glacier, Alaska, in July 2008. To learn about the contributions of glaciers to sea level rise, visit: www.nasa.gov/topics/earth/features/glacier-sea-rise.html Credit: W. Tad Pfeffer, University of Colorado at Boulder NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram
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2017-12-08
Peripheral glaciers and ice caps (isolated from the main ice sheet, which is seen in the upper right section of the image) in eastern Greenland. To learn about the contributions of glaciers to sea level rise, visit: www.nasa.gov/topics/earth/features/glacier-sea-rise.html Credit: Frank Paul, University of Zurich NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram
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2017-12-08
This ice cave in Belcher Glacier (Devon Island, Canada) was formed by melt water flowing within the glacier ice. To learn about the contributions of glaciers to sea level rise, visit: www.nasa.gov/topics/earth/features/glacier-sea-rise.html Credit: Angus Duncan, University of Saskatchewan NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram
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Distribution trend of high-rise buildings worldwide and factor exploration
NASA Astrophysics Data System (ADS)
Yu, Shao-Qiao
2017-08-01
This paper elaborates the development phenomenon of high-rise buildings nowadays. The development trend of super high-rise buildings worldwide is analyzed based on data from the Council on Tall Buildings and Urban Habitat, taking the top 100 high-rise buildings in different continents and with the time development and building type as the objects. Through analysis, the trend of flourishing of UAE super high-rise buildings and stable development of European and American high-rise buildings is obtained. The reasons for different development degrees of the regions are demonstrated from the aspects of social development, economy, culture and consciousness. This paper also presents unavoidable issues of super high-rise buildings and calls for rational treatment to these buildings.
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Ma, Rong; Kaundun, Shiv S.; Tranel, Patrick J.; Riggins, Chance W.; McGinness, Daniel L.; Hager, Aaron G.; Hawkes, Tim; McIndoe, Eddie; Riechers, Dean E.
2013-01-01
Previous research reported the first case of resistance to mesotrione and other 4-hydroxyphenylpyruvate dioxygenase (HPPD) herbicides in a waterhemp (Amaranthus tuberculatus) population designated MCR (for McLean County mesotrione- and atrazine-resistant). Herein, experiments were conducted to determine if target site or nontarget site mechanisms confer mesotrione resistance in MCR. Additionally, the basis for atrazine resistance was investigated in MCR and an atrazine-resistant but mesotrione-sensitive population (ACR for Adams County mesotrione-sensitive but atrazine-resistant). A standard sensitive population (WCS for Wayne County herbicide-sensitive) was also used for comparison. Mesotrione resistance was not due to an alteration in HPPD sequence, HPPD expression, or reduced herbicide absorption. Metabolism studies using whole plants and excised leaves revealed that the time for 50% of absorbed mesotrione to degrade in MCR was significantly shorter than in ACR and WCS, which correlated with previous phenotypic responses to mesotrione and the quantity of the metabolite 4-hydroxy-mesotrione in excised leaves. The cytochrome P450 monooxygenase inhibitors malathion and tetcyclacis significantly reduced mesotrione metabolism in MCR and corn (Zea mays) excised leaves but not in ACR. Furthermore, malathion increased mesotrione activity in MCR seedlings in greenhouse studies. These results indicate that enhanced oxidative metabolism contributes significantly to mesotrione resistance in MCR. Sequence analysis of atrazine-resistant (MCR and ACR) and atrazine-sensitive (WCS) waterhemp populations detected no differences in the psbA gene. The times for 50% of absorbed atrazine to degrade in corn, MCR, and ACR leaves were shorter than in WCS, and a polar metabolite of atrazine was detected in corn, MCR, and ACR that cochromatographed with a synthetic atrazine-glutathione conjugate. Thus, elevated rates of metabolism via distinct detoxification mechanisms contribute to
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The Rise and Fall of Energy Education.
ERIC Educational Resources Information Center
Petrock, Edith M.
This paper discusses the rise and fall of energy education, justifies the commitment to achieve the goals of energy education, and suggests some strategies for accomplishing this objective. The rise of energy education is first discussed. Energy is not a newcomer to the K-12 school instructional program. Energy sources, forms, states, and uses…
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Syria and the Rise of Radical Islamist Groups
2015-03-01
Revolution.” 397 David Blair and Richard Spencer , “How Qatar Is Funding the Rise of Islamist Extremists,” The Telegraph, September 20, 2014, http...Islamists in Syria, Officials Say;” Spencer , “How Qatar Is Funding the Rise of Islamist Extremists.” 411 Amena Bakr, “Defying Allies, Qatar Unlikely...Ibid. 416 Spencer , “How Qatar Is Funding the Rise of Islamist Extremists.” 417 Thomas Hegghammer and Aaron Y. Zelin, “How Syria’s Civil War Became a
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NASA Technical Reports Server (NTRS)
Sterling, A. C.; Moore, R. L.; Harra, L. K.
2006-01-01
EUV data from EIT show that a filament of 2001 February 28 underwent a slow-rise phase lasting about 6 hrs, before rapidly erupting in a fast-rise phase. Concurrent images in soft X-rays (SXRs) from Yohkoh/SXT show that a series of three microflares, prominent in SXT images but weak in EIT approx.195 Ang EUV images, occurred near one end of the filament. The first and last microflares occurred respectively in conjunction with the start of the slow-rise phase and the start of the fast-rise phase, and the second microflare corresponded to a kink in the filament trajectory. Beginning within 10 hours of the start of the slow rise, new magnetic flux emerged at the location of the microflaring. This localized new flux emergence and the resulting microflares, consistent with reconnection between the emerging field and the sheared sigmoid core magnetic field holding the filament, apparently caused the slow rise of this field and the transition to explosive eruption. For the first time in such detail, the observations show this direct action of localized emerging flux in the progressive destabilization of a sheared core field in the onset of a coronal mass ejection (CME). Similar processes may have occurred in other recently-studied events, NASA supported this work through NASA SR&T and SEC GI grants.
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21 CFR 137.270 - Self-rising white corn meal.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Self-rising white corn meal. 137.270 Section 137... Cereal Flours and Related Products § 137.270 Self-rising white corn meal. (a) Self-rising white corn meal is an intimate mixture of white corn meal, sodium bicarbonate, and one or both of the acid-reacting...
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21 CFR 137.270 - Self-rising white corn meal.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Self-rising white corn meal. 137.270 Section 137... Cereal Flours and Related Products § 137.270 Self-rising white corn meal. (a) Self-rising white corn meal is an intimate mixture of white corn meal, sodium bicarbonate, and one or both of the acid-reacting...
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Sensitivity of air quality simulation to smoke plume rise
Yongqiang Liu; Gary Achtemeier; Scott Goodrick
2008-01-01
Plume rise is the height smoke plumes can reach. This information is needed by air quality models such as the Community Multiscale Air Quality (CMAQ) model to simulate physical and chemical processes of point-source fire emissions. This study seeks to understand the importance of plume rise to CMAQ air quality simulation of prescribed burning to plume rise. CMAQ...
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ERIC Educational Resources Information Center
Whitney, Tim
2000-01-01
Examines how tight urban sites can yield sports spaces that favorably compare to their more rural campus counterparts. Potential areas of concern when recreation centers are reconfigured into high-rise structures are highlighted, including building codes, building access, noise control, building costs, and lighting. (GR)
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2013-05-15
An airplane drops essential support on the Austfonna Ice Cap in Svalbard (Norwegian Arctic). The triangular structure is a corner reflector used as ground reference for airborne radar surveys. To learn about the contributions of glaciers to sea level rise, visit: www.nasa.gov/topics/earth/features/glacier-sea-rise.html Credit: Andrea Taurisano, Norwegian Polar Institute NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram
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RISE: a database of RNA interactome from sequencing experiments
Gong, Jing; Shao, Di; Xu, Kui
2018-01-01
Abstract We present RISE (http://rise.zhanglab.net), a database of RNA Interactome from Sequencing Experiments. RNA-RNA interactions (RRIs) are essential for RNA regulation and function. RISE provides a comprehensive collection of RRIs that mainly come from recent transcriptome-wide sequencing-based experiments like PARIS, SPLASH, LIGR-seq, and MARIO, as well as targeted studies like RIA-seq, RAP-RNA and CLASH. It also includes interactions aggregated from other primary databases and publications. The RISE database currently contains 328,811 RNA-RNA interactions mainly in human, mouse and yeast. While most existing RNA databases mainly contain interactions of miRNA targeting, notably, more than half of the RRIs in RISE are among mRNA and long non-coding RNAs. We compared different RRI datasets in RISE and found limited overlaps in interactions resolved by different techniques and in different cell lines. It may suggest technology preference and also dynamic natures of RRIs. We also analyzed the basic features of the human and mouse RRI networks and found that they tend to be scale-free, small-world, hierarchical and modular. The analysis may nominate important RNAs or RRIs for further investigation. Finally, RISE provides a Circos plot and several table views for integrative visualization, with extensive molecular and functional annotations to facilitate exploration of biological functions for any RRI of interest. PMID:29040625
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Fast Electrically Driven Capillary Rise Using Overdrive Voltage.
Hong, Sung Jin; Hong, Jiwoo; Seo, Hee Won; Lee, Sang Joon; Chung, Sang Kug
2015-12-29
Enhancement of response speed (or reduction of response time) is crucial for the commercialization of devices based on electrowetting (EW), such as liquid lenses and reflective displays, and presents one of the main challenges in EW research studies. We demonstrate here that an overdrive EW actuation gives rise to a faster rise of a liquid column between parallel electrodes, compared to a DC EW actuation. Here, DC actuation is actually a simple applied step function, and overdrive is an applied step followed by reduction to a lower voltage. Transient behaviors and response time (i.e., the time required to reach the equilibrium height) of the rising liquid column are explored under different DC and overdrive EW actuations. When the liquid column rises up to a target height by means of an overdrive EW, the response time is reduced to as low as 1/6 of the response time using DC EW. We develop a theoretical model to simulate the EW-driven capillary rise by combining the kinetic equation of capillary flow (i.e., Lucas-Washburn equation) and the dynamic contact angle model considering contact line friction, contact angle hysteresis, contact angle saturation, and the EW effect. This theoretical model accurately predicts the outcome to within a ± 5% error in regard to the rising behaviors of the liquid column with a low viscosity, under both DC EW and overdrive actuation conditions, except for the early stage (
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Historical Cavern Floor Rise for All SPR Sites
DOE Office of Scientific and Technical Information (OSTI.GOV)
Moriarty, Dylan Michael
2016-09-01
The Strategic Petroleum Reserve (SPR) contains the largest supply is the largest stockpile of government-owned emergency crude oil in the world. The oil is stored in multiple salt caverns spread over four sites in Louisiana and Texas. Cavern infrastructure near the bottom of the cavern can be damaged from vertical floor movement. This report presents a comprehensive history of floor movements in each cavern. Most of the cavern floor rise rates ranged from 0.5-3.5 ft/yr, however, there were several caverns with much higher rise rates. BH103, BM106, and BH105 had the three highest rise rates. Information from this report willmore » be used to better predict future vertical floor movements and optimally place cavern infrastructure. The reasons for floor rise are not entirely understood and should be investigated.« less
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Sea-Level Projections from the SeaRISE Initiative
NASA Technical Reports Server (NTRS)
Nowicki, Sophie; Bindschadler, Robert
2011-01-01
SeaRISE (Sea-level Response to Ice Sheet Evolution) is a community organized modeling effort, whose goal is to inform the fifth IPCC of the potential sea-level contribution from the Greenland and Antarctic ice sheets in the 21st and 22nd century. SeaRISE seeks to determine the most likely ice sheet response to imposed climatic forcing by initializing an ensemble of models with common datasets and applying the same forcing to each model. Sensitivity experiments were designed to quantify the sea-level rise associated with a change in: 1) surface mass balance, 2) basal lubrication, and 3) ocean induced basal melt. The range of responses, resulting from the multi-model approach, is interpreted as a proxy of uncertainty in our sea-level projections. http://websrv.cs .umt.edu/isis/index.php/SeaRISE_Assessment.
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Sea Level Rise in Santa Clara County
NASA Technical Reports Server (NTRS)
Milesi, Cristina
2005-01-01
Presentation by Cristina Milesi, First Author, NASA Ames Research Center, Moffett Field, CA at the "Meeting the Challenge of Sea Level Rise in Santa Clara County" on June 19, 2005 Santa Clara County, bordering with the southern portion of the San Francisco Bay, is highly vulnerable to flooding and to sea level rise (SLR). In this presentation, the latest sea level rise projections for the San Francisco Bay will be discussed in the context of extreme water height frequency and extent of flooding vulnerability. I will also present preliminary estimations of levee requirements and possible mitigation through tidal restoration of existing salt ponds. The examples will draw mainly from the work done by the NASA Climate Adaptation Science Investigators at NASA Ames.
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HPLC-PDA analysis and anti-inflammatory effects of Mori Cortex Radicis.
Seo, Chang-Seob; Lim, Hye-Sun; Jeong, Soo-Jin; Ha, Hyekyung; Shin, Hyeun-Kyoo
2013-10-01
Mori Cortex Radicis (MCR, Moraceae) is used traditionally in the treatment ofjaundice, hematemesis, edema, and pollakisuria in Korea. In this study, the antiinflammatory effects of MCR extract were investigated using RAW 264.7 cells. The simultaneous analysis of five components present (neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid, caffeic acid, and p-coumaric acid) in the MCR extract was performed using high-performance liquid chromatography (HPLC) coupled with photodiode array (PDA) detection. We determined the effects of MCR extract and its components on the production of nitric oxide (NO), prostaglandin E2 (PGE2), and mRNA expression of cyclooxygenase-2 (COX-2) in RAW 264.7 cells. MCR extract suppressed the production of NO and PGE2 in RAW 264.7 cells in a dose-dependent manner. None of the five components of the MCR extract had any influence on the production of NO. However, caffeic acid and p-coumaric acid inhibited the production of PGE2 and mRNA expression of COX-2 in RAW 264.7 cells. Our results suggest that MCR extract may offer potential as a therapeutic agent for the treatment of inflammation. The method we have established will help to improve the quality control of MCR extracts.
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Coastal sea level rise with warming above 2 °C
Jevrejeva, Svetlana; Jackson, Luke P.; Riva, Riccardo E. M.; Grinsted, Aslak; Moore, John C.
2016-01-01
Two degrees of global warming above the preindustrial level is widely suggested as an appropriate threshold beyond which climate change risks become unacceptably high. This “2 °C” threshold is likely to be reached between 2040 and 2050 for both Representative Concentration Pathway (RCP) 8.5 and 4.5. Resulting sea level rises will not be globally uniform, due to ocean dynamical processes and changes in gravity associated with water mass redistribution. Here we provide probabilistic sea level rise projections for the global coastline with warming above the 2 °C goal. By 2040, with a 2 °C warming under the RCP8.5 scenario, more than 90% of coastal areas will experience sea level rise exceeding the global estimate of 0.2 m, with up to 0.4 m expected along the Atlantic coast of North America and Norway. With a 5 °C rise by 2100, sea level will rise rapidly, reaching 0.9 m (median), and 80% of the coastline will exceed the global sea level rise at the 95th percentile upper limit of 1.8 m. Under RCP8.5, by 2100, New York may expect rises of 1.09 m, Guangzhou may expect rises of 0.91 m, and Lagos may expect rises of 0.90 m, with the 95th percentile upper limit of 2.24 m, 1.93 m, and 1.92 m, respectively. The coastal communities of rapidly expanding cities in the developing world, and vulnerable tropical coastal ecosystems, will have a very limited time after midcentury to adapt to sea level rises unprecedented since the dawn of the Bronze Age. PMID:27821743
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Coastal sea level rise with warming above 2 °C.
Jevrejeva, Svetlana; Jackson, Luke P; Riva, Riccardo E M; Grinsted, Aslak; Moore, John C
2016-11-22
Two degrees of global warming above the preindustrial level is widely suggested as an appropriate threshold beyond which climate change risks become unacceptably high. This "2 °C" threshold is likely to be reached between 2040 and 2050 for both Representative Concentration Pathway (RCP) 8.5 and 4.5. Resulting sea level rises will not be globally uniform, due to ocean dynamical processes and changes in gravity associated with water mass redistribution. Here we provide probabilistic sea level rise projections for the global coastline with warming above the 2 °C goal. By 2040, with a 2 °C warming under the RCP8.5 scenario, more than 90% of coastal areas will experience sea level rise exceeding the global estimate of 0.2 m, with up to 0.4 m expected along the Atlantic coast of North America and Norway. With a 5 °C rise by 2100, sea level will rise rapidly, reaching 0.9 m (median), and 80% of the coastline will exceed the global sea level rise at the 95th percentile upper limit of 1.8 m. Under RCP8.5, by 2100, New York may expect rises of 1.09 m, Guangzhou may expect rises of 0.91 m, and Lagos may expect rises of 0.90 m, with the 95th percentile upper limit of 2.24 m, 1.93 m, and 1.92 m, respectively. The coastal communities of rapidly expanding cities in the developing world, and vulnerable tropical coastal ecosystems, will have a very limited time after midcentury to adapt to sea level rises unprecedented since the dawn of the Bronze Age.
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An evaluation of rise time characterization and prediction methods
NASA Technical Reports Server (NTRS)
Robinson, Leick D.
1994-01-01
One common method of extrapolating sonic boom waveforms from aircraft to ground is to calculate the nonlinear distortion, and then add a rise time to each shock by a simple empirical rule. One common rule is the '3 over P' rule which calculates the rise time in milliseconds as three divided by the shock amplitude in psf. This rule was compared with the results of ZEPHYRUS, a comprehensive algorithm which calculates sonic boom propagation and extrapolation with the combined effects of nonlinearity, attenuation, dispersion, geometric spreading, and refraction in a stratified atmosphere. It is shown there that the simple empirical rule considerably overestimates the rise time estimate. In addition, the empirical rule does not account for variations in the rise time due to humidity variation or propagation history. It is also demonstrated that the rise time is only an approximate indicator of perceived loudness. Three waveforms with identical characteristics (shock placement, amplitude, and rise time), but with different shock shapes, are shown to give different calculated loudness. This paper is based in part on work performed at the Applied Research Laboratories, the University of Texas at Austin, and supported by NASA Langley.
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Application of tuned mass dampers in high-rise construction
NASA Astrophysics Data System (ADS)
Teplyshev, Vyacheslav; Mylnik, Alexey; Pushkareva, Maria; Agakhanov, Murad; Burova, Olga
2018-03-01
The article considers the use of tuned mass dampers in high-rise construction for significant acceleration and amplitude of vibrations of the upper floors under dynamic wind influences. The susceptibility of people to accelerations in high-rise buildings and possible means of reducing wind-induced fluctuations in buildings are analyzed. The statistics of application of tuned mass dampers in high-rise construction all over the world is presented. The goal of the study is to identify an economically attractive solution that allows the fullest use of the potential of building structures in high-rise construction, abandoning the need to build massive frames leading to over-consumption of materials.
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The communicative functions of final rises in Finnish intonation.
Ogden, Richard; Routarinne, Sara
2005-01-01
This paper considers the communicative function of final rises in Finnish conversational talk between pairs of teenage girls. Final rises are fairly common, occurring approximately twice a minute, predominantly on declaratives and in narrative sequences. We briefly consider the interplay between voice quality (known to be a marker of transition relevance) and rising intonation in Finnish. We argue that in narrative sequences, rising terminals manage two main interactional tasks: they provide a place for a coparticipant to mark recipiency, and they project more talk by the current speaker. Using a methodology which combines phonetic observation with conversation analysis, we demonstrate participants' orientation to these functions.
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Sea Level Rise Impacts On Infrastructure Vulnerability
NASA Astrophysics Data System (ADS)
Pasqualini, D.; Mccown, A. W.; Backhaus, S.; Urban, N. M.
2015-12-01
Increase of global sea level is one of the potential consequences of climate change and represents a threat for the U.S.A coastal regions, which are highly populated and home of critical infrastructures. The potential danger caused by sea level rise may escalate if sea level rise is coupled with an increase in frequency and intensity of storms that may strike these regions. These coupled threats present a clear risk to population and critical infrastructure and are concerns for Federal, State, and particularly local response and recovery planners. Understanding the effect of sea level rise on the risk to critical infrastructure is crucial for long planning and for mitigating potential damages. In this work we quantify how infrastructure vulnerability to a range of storms changes due to an increase of sea level. Our study focuses on the Norfolk area of the U.S.A. We assess the direct damage of drinking water and wastewater facilities and the power sector caused by a distribution of synthetic hurricanes. In addition, our analysis estimates indirect consequences of these damages on population and economic activities accounting also for interdependencies across infrastructures. While projections unanimously indicate an increase in the rate of sea level rise, the scientific community does not agree on the size of this rate. Our risk assessment accounts for this uncertainty simulating a distribution of sea level rise for a specific climate scenario. Using our impact assessment results and assuming an increase of future hurricanes frequencies and intensities, we also estimate the expected benefits for critical infrastructure.
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The Climate Science Special Report: Rising Seas and Changing Oceans
NASA Astrophysics Data System (ADS)
Kopp, R. E.
2017-12-01
GMSL has risen by about 16-21 cm since 1900. Ocean heat content has increased at all depths since the 1960s, and global mean sea-surface temperature increased 0.7°C/century between 1900 to 2016. Human activity contributed substantially to generating a rate of GMSL rise since 1900 faster than during any preceding century in at least 2800 years. A new set of six sea-level rise scenarios, spanning a range from 30 cm to 250 cm of 21st century GMSL rise, were developed for the CSSR. The lower scenario is based on linearly extrapolating the past two decades' rate of rise. The upper scenario is informed by literature estimates of maximum physically plausible values, observations indicating the onset of marine ice sheet instability in parts of West Antarctica, and modeling of ice-cliff and ice-shelf instability mechanisms. The new scenarios include localized projections along US coastlines. There is significant variability around the US, with rates of rise likely greater than GMSL rise in the US Northeast and the western Gulf of Mexico. Under scenarios involving extreme Antarctic contributions, regional rise would be greater than GMSL rise along almost all US coastlines. Historical sea-level rise has already driven a 5- to 10-fold increase in minor tidal flooding in several US coastal cities since the 1960s. Under the CSSR's Intermediate sea-level rise scenario (1.0 m of GMSL rise in 2100) , a majority of NOAA tide gauge locations will by 2040 experience the historical 5-year coastal flood about 5 times per year. Ocean changes are not limited to rising sea levels. Ocean pH is decreasing at a rate that may be unparalleled in the last 66 million years. Along coastlines, ocean acidification can be enhanced by changes in the upwelling (particularly along the US Pacific Coast); by episodic, climate change-enhanced increases in freshwater input (particularly along the US Atlantic Coast); and by the enhancement of biological respiration by nutrient runoff. Climate models project
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Large Topographic Rises on Venus: Implications for Mantle Upwelling
NASA Technical Reports Server (NTRS)
Stofan, Ellen R.; Smrekar, Suzanne E.; Bindschandler, Duane L.; Senske, David A.
1995-01-01
Topographic rises on Venus have been identified that are interpreted to be the surface manifestation of mantle upwellings. These features are classified into groups based on their dominant morphology. Atla and Beta Regiones are classified as rift-dominated, Dione, western Eistla, Bell, and Imdr Regiones as volcano-dominated, and Themis, eastern Eistla, and central Eistla Regiones as corona-dominated. At several topographic rises, geologic indicators were identified that may provide evidence of uplifted topography (e.g., volcanic flow features trending upslope). We assessed the minimum contribution of volcanic construction to the topography of each rise, which in general represents less than 5% of the volume of the rise, similar to the volumes of edifices at terrestrial hotspot swells. The total melt volume at each rise is approximated to be 10(exp 4) - 10(exp 6) cu km. The variations in morphology, topography, and gravity signatures at topographic rises are not interpreted to indicate variations in stage of evolution of a mantle upwelling. Instead, the morphologic variations between the three classes of topographic rises are interpreted to indicate the varying influences of lithospheric structure, plume characteristics, and regional tectonic environment. Within each class, variations in topography, gravity, and amount of volcanism may be indicative of differing stages of evolution. The similarity between swell and volcanic volumes for terrestrial and Venusian hotspots implies comparable time-integrated plume strengths for individual upwellings on the two planets.
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2017-12-08
Calving front of the Perito Moreno Glacier (Argentina). Contrary to the majority of the glaciers from the southern Patagonian ice field, the Perito Moreno Glacier is currently stable. It is also one of the most visited glaciers in the world. To learn about the contributions of glaciers to sea level rise, visit: www.nasa.gov/topics/earth/features/glacier-sea-rise.html Credit: Etienne Berthier, Université de Toulouse NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram
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2017-12-08
The Aletsch Glacier in Switzerland is the largest valley glacier in the Alps. Its volume loss since the middle of the 19th century is well-visible from the trimlines to the right of the image. To learn about the contributions of glaciers to sea level rise, visit: www.nasa.gov/topics/earth/features/glacier-sea-rise.html Credit: Frank Paul, University of Zurich NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram
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NASA Astrophysics Data System (ADS)
Setifi, Fatima; Ota, Akira; Ouahab, Lahcéne; Golhen, Stèphane; Yamochi, Hideki; Saito, Gunzi
2002-11-01
The preparation, X-ray structures and magnetic properties of two isostructural new charge transfer salts: (BO)[ M(isoq) 2(NCS) 4]; M=Cr III(1), Fe III(2) and isoq=isoquinoline are reported. Their structure consists of alternate organic and inorganic layers, each layer being formed by mixed columns of BO radical cations and paramagnetic metal complex anions. There are short intermolecular contacts between donor and anion (S2 anion· · ·S4 BO<3.5 Å) and between adjacent BO molecules (O· · · O1<3.2 Å). The two compounds are insulators. ESR measurements show single signal without separating the donor and anion spins. The magnetic measurements obey the Curie-Weiss law and revealed dominant antiferromagnetic interactions between anion spin and donor spin, but long-range magnetic ordering did not occur down to 2 K. This is directly related to structural reasons which were deduced from a comparison of the title compounds with other 1:1 salts containing same anion complexes and different donors.
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Claritas rise, Mars: Pre-Tharsis magmatism?
Dohm, J.M.; Anderson, R.C.; Williams, J.-P.; Ruiz, J.; McGuire, P.C.; Buczkowski, D.L.; Wang, R.; Scharenbroich, L.; Hare, T.M.; Connerney, J.E.P.; Baker, V.R.; Wheelock, S.J.; Ferris, J.C.; Miyamoto, H.
2009-01-01
Claritas rise is a prominent ancient (Noachian) center of tectonism identified through investigation of comprehensive paleotectonic information of the western hemisphere of Mars. This center is interpreted to be the result of magmatic-driven activity, including uplift and associated tectonism, as well as possible hydrothermal activity. Coupled with its ancient stratigraphy, high density of impact craters, and complex structure, a possible magnetic signature may indicate that it formed during an ancient period of Mars' evolution, such as when the dynamo was in operation. As Tharsis lacks magnetic signatures, Claritas rise may pre-date the development of Tharsis or mark incipient development, since some of the crustal materials underlying Tharsis and older parts of the magmatic complex, respectively, could have been highly resurfaced, destroying any remanent magnetism. Here, we detail the significant characteristics of the Claritas rise, and present a case for why it should be targeted by the Mars Odyssey, Mars Reconnaissance Orbiter, and Mars Express spacecrafts, as well as be considered as a prime target for future tier-scalable robotic reconnaissance. ?? 2009 Elsevier B.V.
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Statistics of EMIC Rising Tones Observed by the Van Allen Probes
NASA Astrophysics Data System (ADS)
Sigsbee, K. M.; Kletzing, C.; Smith, C. W.; Santolik, O.
2017-12-01
We will present results from an ongoing statistical study of electromagnetic ion cyclotron (EMIC) wave rising tones observed by the Van Allen Probes. Using data from the Electric and Magnetic Field Instrument Suite and Integrated Science (EMFISIS) fluxgate magnetometer, we have identified orbits by both Van Allen Probes with EMIC wave events from the start of the mission in fall 2012 through fall 2016. Orbits with EMIC wave events were further examined for evidence of rising tones. Most EMIC wave rising tones were found during H+ band EMIC wave events. In Fourier time-frequency power spectrograms of the fluxgate magnetometer data, H+ band rising tones generally took the form of triggered emission type events, where the discrete rising tone structures rapidly rise in frequency out of the main band of observed H+ EMIC waves. A smaller percentage of EMIC wave rising tone events were found in the He+ band, where rising tones may appear as discrete structures with a positive slope embedded within the main band of observed He+ EMIC waves, similar in appearance to whistler-mode chorus elements. Understanding the occurrence rate and properties of rising tone EMIC waves will provide observational context for theoretical studies indicating that EMIC waves exhibiting non-linear behavior, such as rising tones, may be more effective at scattering radiation belt electrons than ordinary EMIC waves.
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Signaling through the PI 3-K, Akt and SGK Pathway in Breast Cancer Progression
2013-12-01
Cancer Cell Migration The Adherens Junction Protein Afadin is an Akt substrate that Updated version 10.1158/1541-7786. MCR -13-0398doi: Access...the most recent version of this article at: Material Supplementary http://mcr.aacrjournals.org/content/suppl/2013/11/22/1541-7786. MCR -13-0398.DC1...accepted for publication but have not yet been edited. Author Manuscript Published OnlineFirst on November 22, 2013; DOI: 10.1158/1541-7786. MCR -13-0398
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Temperature rise in ion-leachable cements during setting reaction.
Kanchanavasita, W; Pearson, G J; Anstice, H M
1995-11-01
Resin-modified ion-leachable cements have been developed for use as aesthetic restorative materials. Their apparent improved physical and handling properties can make them more attractive for use than conventional glass-ionomers. However, they contain monomers which are known to contract on polymerization and produce a polymerization exotherm. This study evaluated the temperature rise during setting and the rate of dimensional change of several ion-leachable materials. The resin-modified ion-leachable cements demonstrated greater temperature rises and higher rates of contraction than conventional materials. Generally, the behaviour of these resin-modified materials was similar to that of composite resins. However, some resin-modified cements produced a temperature rise of up to 20 degrees C during polymerization which was greater than that of the composite resin. This temperature rise must be taken into account when using the materials in direct contact with dentine in deep cavities without pulp protection. Longer irradiation time than the recommended 20 s did not significantly increase the maximum temperature rise but slightly extended the time before the temperature started to decline. The temperature of the environment had a significant effect on the rate of dimensional change in some materials. The rate of polymerization contraction of light-activated cements was directly related to the observed temperature rise.
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Bangladesh to prepare for rise in gas demand
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1992-06-01
Bangladesh is moving to expand its natural gas infrastructure in response to rising domestic demand. This paper reports that Bangladesh natural gas demand is expected to rise to 700-850 MMcfd in the next few years from the current level of about 500 MMcfd, the Prime Minister Khaleda Zia.
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2017-12-08
Calving front of the Upsala Glacier (Argentina). This glacier has been thinning and retreating at a rapid rate during the last decades – from 2006 to 2010, it receded 43.7 yards (40 meters) per year. During summer 2012, large calving events prevented boat access to the glacier. To learn about the contributions of glaciers to sea level rise, visit: www.nasa.gov/topics/earth/features/glacier-sea-rise.html Credit: Etienne Berthier, Université de Toulouse NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram
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40 CFR Appendix Vi to Part 266 - Stack Plume Rise
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 27 2011-07-01 2011-07-01 false Stack Plume Rise VI Appendix VI to Part 266 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED... FACILITIES Pt. 266, App. VI Appendix VI to Part 266—Stack Plume Rise [Estimated Plume Rise (in Meters) Based...
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40 CFR Appendix Vi to Part 266 - Stack Plume Rise
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 26 2010-07-01 2010-07-01 false Stack Plume Rise VI Appendix VI to Part 266 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED... FACILITIES Pt. 266, App. VI Appendix VI to Part 266—Stack Plume Rise [Estimated Plume Rise (in Meters) Based...
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Coastal Impact Underestimated From Rapid Sea Level Rise
NASA Astrophysics Data System (ADS)
Anderson, John; Milliken, Kristy; Wallace, Davin; Rodriguez, Antonio; Simms, Alexander
2010-06-01
A primary effect of global warming is accelerated sea level rise, which will eventually drown low-lying coastal areas, including some of the world's most populated cities. Predictions from the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) suggest that sea level may rise by as much as 0.6 meter by 2100 [Solomon et al., 2007]. However, uncertainty remains about how projected melting of the Greenland and Antarctic ice sheets will contribute to sea level rise. Further, considerable variability is introduced to these calculations due to coastal subsidence, especially along the northern Gulf of Mexico (see http://tidesandcurrents.noaa.gov/sltrends/sltrends.shtml).
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The Rise of Conservatism since World War II.
ERIC Educational Resources Information Center
Carter, Dan T.
2003-01-01
Discusses the rise of the conservatism movement in the United States since World War II. States that laissez-faire capitalism and the rise of communism contributed to the popularity of conservatism in the United States. Focuses on the role of U.S. Presidents, such as Richard Nixon and Ronald Reagan. (CMK)
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NASA Astrophysics Data System (ADS)
Chee Siang, GO
2017-07-01
Experimental test was carried out to determine the temperature rise characteristics of Portland-Fly-Ash Cement (CEM II/B-V, 42.5N) of Blaine fineness 418.6m2/kg and 444.6m2/kg respectively for 20MPa mass concrete under adiabatic condition. The estimation on adiabatic temperature rise by way of CIRIA C660 method (Construction Industry Research & Information Information) was adopted to verify and validate the hot-box test results by simulating the heat generation curve of the concrete under semi-adiabatic condition. Test result found that Portland fly-ash cement has exhibited decrease in the peak value of temperature rise and maximum temperature rise rate. The result showed that the temperature development and distribution profile, which is directly contributed from the heat of hydration of cement with time, is affected by the insulation, initial placing temperature, geometry and size of concrete mass. The mock up data showing the measured temperature differential is significantly lower than the technical specifications 20°C temperature differential requirement and the 27.7°C limiting temperature differential for granite aggregate concrete as stipulated in BS8110-2: 1985. The concrete strength test result revealed that the 28 days cubes compressive strength was above the stipulated 20MPa characteristic strength at 90 days. The test demonstrated that with proper concrete mix design, the use of Portland flyash cement, combination of chilled water and flake ice, and good insulation is effective in reducing peak temperature rise, temperature differential, and lower adiabatic temperature rise for mass concrete pours. As far as the determined adiabatic temperature rise result was concern, the established result could be inferred for in-situ thermal properties of 20MPa mass concrete application, as the result could be repeatable on account of similar type of constituent materials and concrete mix design adopted for permanent works at project site.
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Spontaneous rise in open rectangular channels under gravity.
Thammanna Gurumurthy, Vignesh; Roisman, Ilia V; Tropea, Cameron; Garoff, Stephen
2018-05-17
Fluid movement in microfluidic devices, porous media, and textured surfaces involves coupled flows over the faces and corners of the media. Spontaneous wetting of simple grooved surfaces provides a model system to probe these flows. This numerical study investigates the spontaneous rise of a liquid in an array of open rectangular channels under gravity, using the Volume-of-Fluid method with adaptive mesh refinement. The rise is characterized by the meniscus height at the channel center, outer face and the interior and exterior corners. At lower contact angles and higher channel aspect ratios, the statics and dynamics of the rise in the channel center show little deviation with the classical model for capillarity, which ignores the existence of corners. For contact angles smaller than 45°, rivulets are formed in the interior corners and a cusp at the exterior corner. The rivulets at long times obey the one-third power law in time, with a weak dependence on the geometry. The cusp behaviour at the exterior corner transforms into a smooth meniscus when the capillary force is higher in the channel, even for contact angles smaller than 45°. The width of the outer face does not influence the capillary rise inside the channel, and the channel size does not influence the rise on the outer face. Copyright © 2018 Elsevier Inc. All rights reserved.
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Inagaki, Fumio; Tsunogai, Urumu; Suzuki, Masae; Kosaka, Ayako; Machiyama, Hideaki; Takai, Ken; Nunoura, Takuro; Nealson, Kenneth H.; Horikoshi, Koki
2004-01-01
Samples from three submerged sites (MC, a core obtained in the methane seep area; MR, a reference core obtained at a distance from the methane seep; and HC, a gas-bubbling carbonate sample) at the Kuroshima Knoll in the southern Ryuku arc were analyzed to gain insight into the organisms present and the processes involved in this oxic-anoxic methane seep environment. 16S rRNA gene analyses by quantitative real-time PCR and clone library sequencing revealed that the MC core sediments contained abundant archaea (∼34% of the total prokaryotes), including both mesophilic methanogens related to the genus Methanolobus and ANME-2 members of the Methanosarcinales, as well as members of the δ-Proteobacteria, suggesting that both anaerobic methane oxidation and methanogenesis occurred at this site. In addition, several functional genes connected with methane metabolism were analyzed by quantitative competitive-PCR, including the genes encoding particulate methane monooxygenase (pmoA), soluble methane monooxygenase (mmoX), methanol dehydrogenese (mxaF), and methyl coenzyme M reductase (mcrA). In the MC core sediments, the most abundant gene was mcrA (2.5 × 106 copies/g [wet weight]), while the pmoA gene of the type I methanotrophs (5.9 × 106 copies/g [wet weight]) was most abundant at the surface of the MC core. These results indicate that there is a very complex environment in which methane production, anaerobic methane oxidation, and aerobic methane oxidation all occur in close proximity. The HC carbonate site was rich in γ-Proteobacteria and had a high copy number of mxaF (7.1 × 106 copies/g [wet weight]) and a much lower copy number of the pmoA gene (3.2 × 102 copies/g [wet weight]). The mmoX gene was never detected. In contrast, the reference core contained familiar sequences of marine sedimentary archaeal and bacterial groups but not groups specific to C1 metabolism. Geochemical characterization of the amounts and isotopic composition of pore water methane and
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Movement characteristics of persons with prader-willi syndrome rising from supine.
Belt, A B; Hertel, T A; Mante, J R; Marks, T; Rockett, V L; Wade, C; Clayton-Krasinski, D
2001-01-01
The purposes of this study were to: 1) determine if previously published descriptors of the supine to stand rising task in healthy individuals could be applied to the movements of persons with Prader-Willi Syndrome (PWS); and 2) assess upper extremity (UE), axial region (AX), and lower extremity (LE) movements among subjects with PWS compared with controls. Nine subjects with PWS (seven-36 years of age) and matched controls were videotaped performing 10 rising trials. The UE, AX, and LE movements were classified using published descriptors. Occurrence frequencies of movement patterns, duration of movement, and the relationships among body region movement score, BMI, and age were determined. Subjects with PWS utilized developmentally less advanced asymmetrical rising patterns, took longer to rise, and demonstrated less within subject variability than controls. Categorical descriptors, with minor modifications, can be used to describe rising movements in persons with PWS. Knowledge of successful rising patterns may assist PTs when examining or planning intervention strategies for teaching the rising task.
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Caltagirone, Mariasofia; Nucleo, Elisabetta; Spalla, Melissa; Zara, Francesca; Novazzi, Federica; Marchetti, Vittoria M.; Piazza, Aurora; Bitar, Ibrahim; De Cicco, Marica; Paolucci, Stefania; Pilla, Giorgio; Migliavacca, Roberta; Pagani, Laura
2017-01-01
To evaluate the water compartment antibiotic-resistance contamination rates, 11 wells, five streams, and four treatment plants located in the Oltrepò Pavese area were screened for the presence of third generation cephalosporins resistant Gram-negative bacteria. Enterobacteriaceae were also characterized for the Extended-Spectrum-β-Lactamases (ESBLs), carbapenemases, and mcr-1 genes presence. From December 2014 to November 2015, 246 water samples were filtered, plated on Plate Count Agar, MacConkey Agar, and MacConkey Agar with cefotaxime. Isolates were species identified using AutoSCAN-4-System and ESBLs, carbapenemases, and colistin resistance determinants were characterized by PCR, sequencing, and microarray. Plasmid conjugative transfer experiments, PCR-based Replicon typing, Pulsed-Field Gel Electrophoresis, Multi-Locus-Sequence-Typing, and in-silico plasmid characterization were performed. A total of 132 enterobacteria isolates grew on MacConkey agar with cefotaxime: 82 (62.1%) were obtained from streams, 41 (31.1%) from treatment plants, and 9 (6.8%) from wells. Thirty out of 132 (22.7%) isolates, mainly belonging to Escherichia coli (n = 15) species, showed a synergic effect with piperacillin-tazobactam. A single ESBL gene of blaCTX−M-type was identified in 19/30 isolates. In further two E. coli strains, a blaCTX−M−1 gene co-existed with a blaSHV-type ESBL determinant. A blaSHV−12 gene was detected in two isolates of E. coli (n = 1) and Klebsiella oxytoca (n = 1), while any ESBL determinant was ascertained in seven Yersinia enterocolitica strains. A blaDHA-type gene was detected in a cefoxitin resistant Y. enterocolitica from a stream. Interestingly, two Klebsiella pneumoniae strains of ST307 and ST258, collected from a well and a wastewater treatment plant, resulted KPC-2, and KPC-3 producers, respectively. Moreover, we report the first detection of mcr-1.2 ST10 E. coli on a conjugative IncX4 plasmid (33.303 bp in size) from a stream of Oltrep
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Specific features of modern multifunctional high-rise building construction
NASA Astrophysics Data System (ADS)
Manukhina, Lyubov; Samosudova, Natal'ja
2018-03-01
The article analyzes the main reasons for the development of high-rise building construction the most important of which-is a limitation of the urban areas and, consequently, the high price of land reserved for construction. New engineering and compositional solutions for the creation of new types of buildings are considered - complex technical designs of a large number of storeys completely meet the new requirements for safety and comfort. Some peculiarities of designing high-rise buildings and searching for optimal architectural and planning solutions are revealed since, with external architectural simplicity, high-rise buildings have complex structural and technological and space-planning solutions. We consider the specific features of a high-rise housing in various countries around the world, including Russia, such as the layout of the multi-storey residential buildings, depending on the climatic characteristics of the regions, assessment of the geological risk of the construction site, the choice of parameters and functional purpose of the sections of the territory of high-rise construction, location of the town-planning object for substantiating the overall dimensions of the building, assessment of changes aeration and engineering and hydrological conditions of the site. A special place in the article on the problems of improvement of the territory, the device of courtyards, landscaping, the device of playing and sports grounds. The main conclusion in the article is the following problem - when developing high-rise housing construction, the development of high-rise housing, and an increase in the population density in the territory of large cities of Russia, necessary to create a comfortable and safe level of residents living and not a decrease, but an improvement in the quality of the urban environment.
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Capillary Rise: Validity of the Dynamic Contact Angle Models.
Wu, Pingkeng; Nikolov, Alex D; Wasan, Darsh T
2017-08-15
The classical Lucas-Washburn-Rideal (LWR) equation, using the equilibrium contact angle, predicts a faster capillary rise process than experiments in many cases. The major contributor to the faster prediction is believed to be the velocity dependent dynamic contact angle. In this work, we investigated the dynamic contact angle models for their ability to correct the dynamic contact angle effect in the capillary rise process. We conducted capillary rise experiments of various wetting liquids in borosilicate glass capillaries and compared the model predictions with our experimental data. The results show that the LWR equations modified by the molecular kinetic theory and hydrodynamic model provide good predictions on the capillary rise of all the testing liquids with fitting parameters, while the one modified by Joos' empirical equation works for specific liquids, such as silicone oils. The LWR equation modified by molecular self-layering model predicts well the capillary rise of carbon tetrachloride, octamethylcyclotetrasiloxane, and n-alkanes with the molecular diameter or measured solvation force data. The molecular self-layering model modified LWR equation also has good predictions on the capillary rise of silicone oils covering a wide range of bulk viscosities with the same key parameter W(0), which results from the molecular self-layering. The advantage of the molecular self-layering model over the other models reveals the importance of the layered molecularly thin wetting film ahead of the main meniscus in the energy dissipation associated with dynamic contact angle. The analysis of the capillary rise of silicone oils with a wide range of bulk viscosities provides new insights into the capillary dynamics of polymer melts.
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Rising Food Prices: Who's Responsible?
ERIC Educational Resources Information Center
Brown, Lester R.
1973-01-01
Rise in food prices can be partially attributed to the high food consumption level throughout Europe and North America, coupled with failure to evolve systems for more production of cattle, soybeans, and fisheries at lower cost. (PS)
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Sea-level rise risks to coastal cities
NASA Astrophysics Data System (ADS)
Nicholls, Robert J.
2017-04-01
Understanding the consequence of sea-level rise for coastal cities has long lead times and huge political implications. Civilisation has emerged and developed during a period of several thousand years during which in geological terms sea level has been unusually stable. We have now moved out of this period and the challenge will be to develop a long-term proactive assessment approach to manage this challenge. In 2005 there were 136 coastal cities with a population exceeding one million people and a collective population of 400 million people. All these coastal cities are threatened by flooding from the sea to varying degrees and these risks are increasing due to growing exposure (people and assets), rising sea levels due to climate change, and in some cities, significant coastal subsidence due to human agency (drainage and groundwater withdrawals from susceptible soils). In these cities we wish to avoid major flood events, with associated damage and potentially deaths and ultimately decline of the cities. Flood risks grow with sea-level rise as it raises extreme sea levels. As sea levels continue to rise, protection will have to be progressively upgraded. Even with this, the magnitude of losses when flood events do occur would increase as coastal cities expand, and water depths and hence unit damage increase with sea-level rise/subsidence. This makes it critical to also prepare for larger coastal flood disasters than we experience today and raises questions on the limits to adaptation. There is not an extensive literature or significant empirical information on the limits to adaptation in coastal cities. These limits are not predictable in a formal sense - while the rise in mean sea level raises the likelihood of a catastrophic flood, extreme events are what cause damage and trigger a response, be it abandonment, a defence upgrade or something else. There are several types of potential limits that could be categorised into three broad types: • Physical
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NASA Astrophysics Data System (ADS)
Hegazy, Maha A.; Abdelwahab, Nada S.; Fayed, Ahmed S.
2015-04-01
A novel method was developed for spectral resolution and further determination of five-component mixture including Vitamin B complex (B1, B6, B12 and Benfotiamine) along with the commonly co-formulated Diclofenac. The method is simple, sensitive, precise and could efficiently determine the five components by a complementary application of two different techniques. The first is univariate second derivative method that was successfully applied for determination of Vitamin B12. The second is Multivariate Curve Resolution using the Alternating Least Squares method (MCR-ALS) by which an efficient resolution and quantitation of the quaternary spectrally overlapped Vitamin B1, Vitamin B6, Benfotiamine and Diclofenac sodium were achieved. The effect of different constraints was studied and the correlation between the true spectra and the estimated spectral profiles were found to be 0.9998, 0.9983, 0.9993 and 0.9933 for B1, B6, Benfotiamine and Diclofenac, respectively. All components were successfully determined in tablets and capsules and the results were compared to HPLC methods and they were found to be statistically non-significant.
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Visualizing Sea Level Rise with Augmented Reality
NASA Astrophysics Data System (ADS)
Kintisch, E. S.
2013-12-01
Looking Glass is an application on the iPhone that visualizes in 3-D future scenarios of sea level rise, overlaid on live camera imagery in situ. Using a technology known as augmented reality, the app allows a layperson user to explore various scenarios of sea level rise using a visual interface. Then the user can see, in an immersive, dynamic way, how those scenarios would affect a real place. The first part of the experience activates users' cognitive, quantitative thinking process, teaching them how global sea level rise, tides and storm surge contribute to flooding; the second allows an emotional response to a striking visual depiction of possible future catastrophe. This project represents a partnership between a science journalist, MIT, and the Rhode Island School of Design, and the talk will touch on lessons this projects provides on structuring and executing such multidisciplinary efforts on future design projects.
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Overestimation of marsh vulnerability to sea level rise
Kirwan, Matthew L.; Temmerman, Stijn; Skeehan, Emily E.; Guntenspergen, Glenn R.; Fagherazzi, Sergio
2016-01-01
Coastal marshes are considered to be among the most valuable and vulnerable ecosystems on Earth, where the imminent loss of ecosystem services is a feared consequence of sea level rise. However, we show with a meta-analysis that global measurements of marsh elevation change indicate that marshes are generally building at rates similar to or exceeding historical sea level rise, and that process-based models predict survival under a wide range of future sea level scenarios. We argue that marsh vulnerability tends to be overstated because assessment methods often fail to consider biophysical feedback processes known to accelerate soil building with sea level rise, and the potential for marshes to migrate inland.
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Future sea level rise constrained by observations and long-term commitment.
Mengel, Matthias; Levermann, Anders; Frieler, Katja; Robinson, Alexander; Marzeion, Ben; Winkelmann, Ricarda
2016-03-08
Sea level has been steadily rising over the past century, predominantly due to anthropogenic climate change. The rate of sea level rise will keep increasing with continued global warming, and, even if temperatures are stabilized through the phasing out of greenhouse gas emissions, sea level is still expected to rise for centuries. This will affect coastal areas worldwide, and robust projections are needed to assess mitigation options and guide adaptation measures. Here we combine the equilibrium response of the main sea level rise contributions with their last century's observed contribution to constrain projections of future sea level rise. Our model is calibrated to a set of observations for each contribution, and the observational and climate uncertainties are combined to produce uncertainty ranges for 21st century sea level rise. We project anthropogenic sea level rise of 28-56 cm, 37-77 cm, and 57-131 cm in 2100 for the greenhouse gas concentration scenarios RCP26, RCP45, and RCP85, respectively. Our uncertainty ranges for total sea level rise overlap with the process-based estimates of the Intergovernmental Panel on Climate Change. The "constrained extrapolation" approach generalizes earlier global semiempirical models and may therefore lead to a better understanding of the discrepancies with process-based projections.
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Future sea level rise constrained by observations and long-term commitment
Mengel, Matthias; Levermann, Anders; Frieler, Katja; Robinson, Alexander; Marzeion, Ben; Winkelmann, Ricarda
2016-01-01
Sea level has been steadily rising over the past century, predominantly due to anthropogenic climate change. The rate of sea level rise will keep increasing with continued global warming, and, even if temperatures are stabilized through the phasing out of greenhouse gas emissions, sea level is still expected to rise for centuries. This will affect coastal areas worldwide, and robust projections are needed to assess mitigation options and guide adaptation measures. Here we combine the equilibrium response of the main sea level rise contributions with their last century's observed contribution to constrain projections of future sea level rise. Our model is calibrated to a set of observations for each contribution, and the observational and climate uncertainties are combined to produce uncertainty ranges for 21st century sea level rise. We project anthropogenic sea level rise of 28–56 cm, 37–77 cm, and 57–131 cm in 2100 for the greenhouse gas concentration scenarios RCP26, RCP45, and RCP85, respectively. Our uncertainty ranges for total sea level rise overlap with the process-based estimates of the Intergovernmental Panel on Climate Change. The “constrained extrapolation” approach generalizes earlier global semiempirical models and may therefore lead to a better understanding of the discrepancies with process-based projections. PMID:26903648
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Sea-level rise: towards understanding local vulnerability
NASA Astrophysics Data System (ADS)
Rahmstorf, Stefan
2012-06-01
Projections of global sea-level rise into the future have become more pessimistic over the past five years or so. A global rise by more than one metre by the year 2100 is now widely accepted as a serious possibility if greenhouse gas emissions continue unabated. That is witnessed by the scientific assessments that were made since the last IPCC report was published in 2007. The Delta Commission of the Dutch government projected up to 1.10 m as a 'high-end' scenario (Vellinga et al 2009). The Scientific Committee on Antarctic Research (SCAR) projected up to 1.40 m (Scientific Committee on Antarctic Research 2009), and the Arctic Monitoring and Assessment Programme (AMAP) gives a range of 0.90-1.60 m in its 2011 report (Arctic Monitoring and Assessment Programme 2011). And recently the US Army Corps of Engineers recommends using a 'low', an 'intermediate' and a 'high' scenario for global sea-level rise when planning civil works programmes, with the high one corresponding to a 1.50 m rise by 2100 (US Army Corps of Engineers 2011). This more pessimistic view is based on a number of observations, most importantly perhaps the fact that sea level has been rising at least 50% faster in the past decades than projected by the IPCC (Rahmstorf et al 2007, IPCC 2007). Also, the rate of rise (averaged over two decades) has accelerated threefold, from around 1 mm yr-1 at the start of the 20th century to around 3 mm yr-1 over the past 20 years (Church and White 2006), and this rate increase closely correlates with global warming (Rahmstorf et al 2011). The IPCC projections, which assume almost no further acceleration in the 20th century, thus look less plausible. And finally the observed net mass loss of the two big continental ice sheets (Van den Broeke et al 2011) calls into question the assumption that ice accumulation in Antarctica would largely balance ice loss from Greenland in the course of further global warming (IPCC 2007). With such a serious sea-level rise on the horizon
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The New Woman in "The Sun Also Rises"
ERIC Educational Resources Information Center
Yu, Xiaoping
2010-01-01
Hemingway is a famous American writer and a spokesman of the Lost Generation. His life attitude of the characters in the novels influenced the whole world. His first masterpiece "The Sun Also Rises" contributes a lot to the rise of feminism and make the world began to be familiar with a term: The New Woman through the portrayal of Brett.…
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Short rise time intense electron beam generator
Olson, Craig L.
1987-01-01
A generator for producing an intense relativistic electron beam having a subnanosecond current rise time includes a conventional generator of intense relativistic electrons feeding into a short electrically conductive drift tube including a cavity containing a working gas at a low enough pressure to prevent the input beam from significantly ionizing the working gas. Ionizing means such as a laser simultaneously ionize the entire volume of working gas in the cavity to generate an output beam having a rise time less than one nanosecond.
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Short rise time intense electron beam generator
Olson, C.L.
1984-03-16
A generator for producing an intense relativisitc electron beam having a subnanosecond current rise time includes a conventional generator of intense relativistic electrons feeding into a short electrically conductive drift tube including a cavity containing a working gas at a low enough pressure to prevent the input beam from significantly ionizing the working gas. Ionizing means such as a laser simultaneously ionize the entire volume of working gas in the cavity to generate an output beam having a rise time less than one nanosecond.
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Methods of erection of high-rise buildings
NASA Astrophysics Data System (ADS)
Cherednichenko, Nadezhda; Oleinik, Pavel
2018-03-01
The article contains the factors determining the choice of methods for organizing the construction and production of construction and installation work for the construction of high-rise buildings. There are also indicated specific features of their underground parts, characterized by powerful slab-pile foundations, large volumes of earthworks, reinforced bases and foundations for assembly cranes. The work cycle is considered when using reinforced concrete, steel and combined skeletons of high-rise buildings; the areas of application of flow, separate and complex methods are being disclosed. The main conditions for the erection of high-rise buildings and their components are singled out: the choice of formwork systems, delivery and lifting of concrete mixes, installation of reinforcement, the formation of lifting and transporting and auxiliary equipment. The article prescribes the reserves of reduction in the duration of construction due to the creation of: complex mechanized technologies for the efficient construction of foundations in various soil conditions, including in the heaving, swelling, hindered, subsidence, bulk, water-saturated forms; complex mechanized technologies for the erection of monolithic reinforced concrete structures, taking into account the winter conditions of production and the use of mobile concrete-laying complexes and new generation machines; modular formwork systems, distinguished by their versatility, ease, simplicity in operation suitable for complex high-rise construction; more perfect methodology and the development of a set of progressive organizational and technological solutions that ensure a rational relationship between the processes of production and their maximum overlap in time and space.
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Online Citizen Science with Clickworkers & MRO HiRISE E/PO
NASA Astrophysics Data System (ADS)
Gulick, V. C.; Deardorff, G.; Kanefsky, B.; HiRISE Science Team
2010-12-01
The High-Resolution Imaging Science Experiment’s E/PO has fielded several online citizen science projects. Our efforts are guided by HiRISE E/PO’s philosophy of providing innovative opportunities for students and the public to participate in the scientific discovery process. HiRISE Clickworkers, a follow-on to the original Clickworkers crater identification and size diameter marking website, provides an opportunity for the public to identify & mark over a dozen landform feature types in HiRISE images, including dunes, gullies, patterned ground, wind streaks, boulders, craters, layering, volcanoes, etc. In HiRISE Clickworkers, the contributor views several sample images showing variations of different landforms, and simply marks all the landform types they could spot while looking at a small portion of a HiRISE image. Contributors then submit their work & once validated by comparison to the output of other participants, results are then added to geologic feature databases. Scientists & others will eventually be able to query these databases for locations of particular geologic features in the HiRISE images. Participants can also mark other features that they find intriguing for the HiRISE camera to target. The original Clickworkers website pilot study ran from November 2000 until September 2001 (Kanefsky et al., 2001, LPSC XXXII). It was among the first online Citizen Science efforts for planetary science. In its pilot study, we endeavored to answer two questions: 1) Was the public willing & able to help science, & 2) Can the public produce scientifically useful results? Since its inception over 3,500,000 craters have been identified, & over 350,000 of these craters have been classified. Over 2 million of these craters were marked on Viking Orbiter image mosaics, nearly 800,000 craters were marked on Mars Orbiter Camera (MOC) images. Note that these are not counts of distinct craters. For example, each crater in the Viking orbiter images was counted by about 50
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The RiSE climbing robot: body and leg design
NASA Astrophysics Data System (ADS)
Saunders, A.; Goldman, D. I.; Full, R. J.; Buehler, M.
2006-05-01
The RiSE robot is a biologically inspired, six legged climbing robot, designed for general mobility in scansorial (vertical walls, horizontal ledges, ground level) environments. It exhibits ground reaction forces that are similar to animal climbers and does not rely on suction, magnets or other surface-dependent specializations to achieve adhesion and shear force. We describe RiSE's body and leg design as well as its electromechanical, communications and computational infrastructure. We review design iterations that enable RiSE to climb 90° carpeted, cork covered and (a growing range of) stucco surfaces in the quasi-static regime.
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Integrating wildfire plume rises within atmospheric transport models
NASA Astrophysics Data System (ADS)
Mallia, D. V.; Kochanski, A.; Wu, D.; Urbanski, S. P.; Krueger, S. K.; Lin, J. C.
2016-12-01
Wildfires can generate significant pyro-convection that is responsible for releasing pollutants, greenhouse gases, and trace species into the free troposphere, which are then transported a significant distance downwind from the fire. Oftentimes, atmospheric transport and chemistry models have a difficult time resolving the transport of smoke from these wildfires, primarily due to deficiencies in estimating the plume injection height, which has been highlighted in previous work as the most important aspect of simulating wildfire plume transport. As a result of the uncertainties associated with modeled wildfire plume rise, researchers face difficulties modeling the impacts of wildfire smoke on air quality and constraining fire emissions using inverse modeling techniques. Currently, several plume rise parameterizations exist that are able to determine the injection height of fire emissions; however, the success of these parameterizations has been mixed. With the advent of WRF-SFIRE, the wildfire plume rise and injection height can now be explicitly calculated using a fire spread model (SFIRE) that is dynamically linked with the atmosphere simulated by WRF. However, this model has only been tested on a limited basis due to computational costs. Here, we will test the performance of WRF-SFIRE in addition to several commonly adopted plume parameterizations (Freitas, Sofiev, and Briggs) for the 2013 Patch Springs (Utah) and 2012 Baker Canyon (Washington) fires, for both of which observations of plume rise heights are available. These plume rise techniques will then be incorporated within a Lagrangian atmospheric transport model (STILT) in order to simulate CO and CO2 concentrations during NASA's CARVE Earth Science Airborne Program over Alaska during the summer of 2012. Initial model results showed that STILT model simulations were unable to reproduce enhanced CO concentrations produced by Alaskan fires observed during 2012. Near-surface concentrations were drastically
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Historical Perspective on the Rise and Fall and Rise of Antibiotics and Human Weight Gain.
Podolsky, Scott H
2017-01-17
In recent medical and popular literature, audiences have been asked to consider whether antibiotics have contributed to the rising obesity epidemic. Prominent magazines have stated that weight may be adversely affected by antibiotics that destroy existing microbiomes and replace them with less helpful ones. However, there is a long history of efforts to investigate the relationship between antibiotics and human weight gain. In the early 1950s, amid initial findings that low doses of antibiotics served as growth promoters in animal livestock, investigators explored the role of antibiotics as magic bullets for human malnutrition. Nevertheless, early enthusiasm was tempered by controlled studies showing that antibiotics did not serve as useful, nonspecific growth promoters for humans. In subsequent decades, against the backdrop of rising concern over antibiotic resistance, investigators studying the role of antibiotics in acute malnutrition have had to navigate a more complicated public health calculus. In a related historical stream, scientists since the 1910s have explored the role of the intestinal microflora in human health. By the 2000s, as increasing resources and more sophisticated tools were devoted to understanding the microbiome (a term coined in 2001), attention would turn to the role of antibiotics and the intestinal microflora in the rising obesity epidemic. Despite scientific and commercial enthusiasm, easy answers (whether about antibiotics or probiotics) have again given way to an appreciation for the complexity of human growth. History encourages caution about our hopes for simplistic answers for presumed "fat drugs" and slimming probiotics alike.
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Reliability and Validity of the Standing Heel-Rise Test
ERIC Educational Resources Information Center
Yocum, Allison; McCoy, Sarah Westcott; Bjornson, Kristie F.; Mullens, Pamela; Burton, Gay Naganuma
2010-01-01
A standardized protocol for a pediatric heel-rise test was developed and reliability and validity are reported. Fifty-seven children developing typically (CDT) and 34 children with plantar flexion weakness performed three tests: unilateral heel rise, vertical jump, and force measurement using handheld dynamometry. Intraclass correlation…
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Neural Control of Fundamental Frequency Rise and Fall in Mandarin Tones
ERIC Educational Resources Information Center
Howell, Peter; Jiang, Jing; Peng, Danling; Lu, Chunming
2012-01-01
The neural mechanisms used in tone rises and falls in Mandarin were investigated. Nine participants were scanned while they named one-character pictures that required rising or falling tone responses in Mandarin: the left insula and right putamen showed stronger activation between rising and falling tones; the left brainstem showed weaker…
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Salt marsh persistence is threatened by predicted sea-level rise
NASA Astrophysics Data System (ADS)
Crosby, Sarah C.; Sax, Dov F.; Palmer, Megan E.; Booth, Harriet S.; Deegan, Linda A.; Bertness, Mark D.; Leslie, Heather M.
2016-11-01
Salt marshes buffer coastlines and provide critical ecosystem services from storm protection to food provision. Worldwide, these ecosystems are in danger of disappearing if they cannot increase elevation at rates that match sea-level rise. However, the magnitude of loss to be expected is not known. A synthesis of existing records of salt marsh elevation change was conducted in order to consider the likelihood of their future persistence. This analysis indicates that many salt marshes did not keep pace with sea-level rise in the past century and kept pace even less well over the past two decades. Salt marshes experiencing higher local sea-level rise rates were less likely to be keeping pace. These results suggest that sea-level rise will overwhelm most salt marshes' capacity to maintain elevation. Under the most optimistic IPCC emissions pathway, 60% of the salt marshes studied will be gaining elevation at a rate insufficient to keep pace with sea-level rise by 2100. Without mitigation of greenhouse gas emissions this potential loss could exceed 90%, which will have substantial ecological, economic, and human health consequences.
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Igneous rocks of the East Pacific Rise
Engel, A.E.J.; Engel, C.G.
1964-01-01
The apical parts of large volcanoes along the East Pacific Rise (islands and seamounts) are encrusted with rocks of the alkali volcanic suite (alkali basalt, andesine- and oligoclase-andesite, and trachyte). In contrast, the more submerged parts of the Rise are largely composed of a tholeiitic basalt which has low concentrations of K, P, U, Th, Pb, and Ti. This tholeiitic basalt is either the predominant or the only magma generated in the earth's mantle under oceanic ridges and rises. It is at least 1000-fold more abundant than the alkali suite, which is probably derived from tholeiitic basalt by magmatic differentiation in and immediately below the larger volcanoes. Distinction of oceanic tholeiites from almost all continental tholeiites is possible on the simple basis of total potassium content, with the discontinuity at 0.3 to 0.5 percent K2O by weight. Oceanic tholeiites also are readily distinguished from some 19 out of 20 basalts of oceanic islands and seamount cappings by having less than 0.3 percent K2O by weight and more than 48 percent SiO2. Deep drilling into oceanic volcanoes should, however, core basalts transitional between the oceanic tholeiites and the presumed derivative alkali basalts.The composition of the oceanic tholeiites suggests that the mantle under the East Pacific Rise contains less than 0.10 percent potassium oxide by weight; 0.1 part per million of uranium and 0.4 part of thorium; a potassium:rubidium ratio of about 1200 and a potassium: uranium ratio of about 104.
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Telling the Story of MindRising: Minecraft, Mindfulness and Meaningful Learning
ERIC Educational Resources Information Center
Butler, Deirdre; Brown, Mark; Críosta, Gar Mac
2016-01-01
This paper describes a unique project known as MindRising Games. It reports how the innovative use of Minecraft™ combined with the principles of mindfulness and meaningful learning contributed to rich digital story telling. MindRising Games was a competition, which was part of the 100-year commemoration of the Easter Rising, designed to celebrate…
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What's Behind Rising Insurance Costs?
ERIC Educational Resources Information Center
Adams, Velma A.
1970-01-01
Rising risks, and losses resulting from civil disorders and vandalism are producing a squeeze on profits thus precipitating higher property insurance rates and deductibles, according to the insurance industry; while schoolmen lay the blame on industry panic. The conclusion is that school and insurance representatives must work together toward the…
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Mars reconnaissance orbiter's high resolution imaging science experiment (HiRISE)
McEwen, A.S.; Eliason, E.M.; Bergstrom, J.W.; Bridges, N.T.; Hansen, C.J.; Delamere, W.A.; Grant, J. A.; Gulick, V.C.; Herkenhoff, K. E.; Keszthelyi, L.; Kirk, R.L.; Mellon, M.T.; Squyres, S. W.; Thomas, N.; Weitz, C.M.
2007-01-01
The HiRISE camera features a 0.5 m diameter primary mirror, 12 m effective focal length, and a focal plane system that can acquire images containing up to 28 Gb (gigabits) of data in as little as 6 seconds. HiRISE will provide detailed images (0.25 to 1.3 m/pixel) covering ???1% of the Martian surface during the 2-year Primary Science Phase (PSP) beginning November 2006. Most images will include color data covering 20% of the potential field of view. A top priority is to acquire ???1000 stereo pairs and apply precision geometric corrections to enable topographic measurements to better than 25 cm vertical precision. We expect to return more than 12 Tb of HiRISE data during the 2-year PSP, and use pixel binning, conversion from 14 to 8 bit values, and a lossless compression system to increase coverage. HiRISE images are acquired via 14 CCD detectors, each with 2 output channels, and with multiple choices for pixel binning and number of Time Delay and Integration lines. HiRISE will support Mars exploration by locating and characterizing past, present, and future landing sites, unsuccessful landing sites, and past and potentially future rover traverses. We will investigate cratering, volcanism, tectonism, hydrology, sedimentary processes, stratigraphy, aeolian processes, mass wasting, landscape evolution, seasonal processes, climate change, spectrophotometry, glacial and periglacial processes, polar geology, and regolith properties. An Internet Web site (HiWeb) will enable anyone in the world to suggest HiRISE targets on Mars and to easily locate, view, and download HiRISE data products. Copyright 2007 by the American Geophysical Union.
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Projecting Future Sea Level Rise for Water Resources Planning in California
NASA Astrophysics Data System (ADS)
Anderson, J.; Kao, K.; Chung, F.
2008-12-01
Sea level rise is one of the major concerns for the management of California's water resources. Higher water levels and salinity intrusion into the Sacramento-San Joaquin Delta could affect water supplies, water quality, levee stability, and aquatic and terrestrial flora and fauna species and their habitat. Over the 20th century, sea levels near San Francisco Bay increased by over 0.6ft. Some tidal gauge and satellite data indicate that rates of sea level rise are accelerating. Sea levels are expected to continue to rise due to increasing air temperatures causing thermal expansion of the ocean and melting of land-based ice such as ice on Greenland and in southeastern Alaska. For water planners, two related questions are raised on the uncertainty of future sea levels. First, what is the expected sea level at a specific point in time in the future, e.g., what is the expected sea level in 2050? Second, what is the expected point of time in the future when sea levels will exceed a certain height, e.g., what is the expected range of time when the sea level rises by one foot? To address these two types of questions, two factors are considered: (1) long term sea level rise trend, and (2) local extreme sea level fluctuations. A two-step approach will be used to develop sea level rise projection guidelines for decision making that takes both of these factors into account. The first step is developing global sea level rise probability distributions for the long term trends. The second step will extend the approach to take into account the effects of local astronomical tides, changes in atmospheric pressure, wind stress, floods, and the El Niño/Southern Oscillation. In this paper, the development of the first step approach is presented. To project the long term sea level rise trend, one option is to extend the current rate of sea level rise into the future. However, since recent data indicate rates of sea level rise are accelerating, methods for estimating sea level rise
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Anthropogenic sea level rise and adaptation in the Yangtze estuary
NASA Astrophysics Data System (ADS)
Cheng, H.; Chen, J.; Chen, Z.; Ruan, R.; Xu, G.; Zeng, G.; Zhu, J.; Dai, Z.; Gu, S.; Zhang, X.; Wang, H.
2016-02-01
Sea level rise is a major projected threat of climate change. There are regional variations in sea level changes, depending on both naturally the tectonic subsidence, geomorphology, naturally changing river inputs and anthropogenic driven forces as artificial reservoir water impoundment within the watershed and urban land subsidence driven by ground water depletion in the river delta. Little is known on regional sea level fall in response to the channel erosion due to the sediment discharge decline by reservoir interception in the upstream watershed, and water level rise driven by anthropogenic measures as the land reclamation, deep waterway regulation and fresh water reservoir construction to the sea level change in estuaries. Changing coastal cities are situated in the delta regions expected to be threatened in various degrees. Shanghai belongs to those cities. Here we show that the anthropogenic driven sea level rise in the Yangtze estuary from the point of view of the continuous hydrodynamic system consisted of river catchment, estuary and coastal sea. Land subsidence is cited as 4 mm/a (2011-2030). Scour depth of the estuarine channel by upstream engineering as Three Gauge Dam is estimated at 2-10 cm (2011-2030). The rise of water level by deep waterway and land reclamation is estimated at 8-10 cm (2011-2030). The relative sea level rise will be speculated about 10 -16 cm (2011-2030), which these anthropogenic sea level changes will be imposed into the absolute sea level rise 2 mm/a and tectonic subsidence 1 mm/a measured in 1990s. The action guideline to the sea level rise strategy in the Shanghai city have been proposed to the Shanghai government as (1) recent actions (2012-2015) to upgrade the city water supply and drainage engineering and protective engineering; (2) interim actions (2016-2020) to improve sea level monitoring and early warning system, and then the special, city, regional planning considering sea level rise; (3) long term actions (2021
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Metabolic clearance and production rates of human growth hormone
Taylor, Andrew L.; Finster, Joseph L.; Mintz, Daniel H.
1969-01-01
The metabolic clearance rate (MCR) of human growth hormone (HGH) was determined by the constant infusion to equilibrium technique utilizing HGH-125I. 22 control subjects had a MCR of 229 ±52 ml/min (mean ±SD). No difference was evident between sexes, or between various age groups. Patients with acromegaly demonstrated normal MCR's. Moreover, acute elevations of plasma growth hormone concentrations in normal subjects did not alter the MCR of HGH. The MCR was relatively constant from day to day and within the day when subjects were evaluated in the supine position. In contrast, the assumption of the upright position was associated with a mean 24% decrease in the MCR. These results were contrasted with the MCR of HGH observed in a small number of patients with altered thyroid function or diabetes mellitus. In six patients with hypothyroidism the MCR (131 ±36 ml/min) was significantly decreased (P < 0.001); whereas the MCR in eight patients with hyperthyroidism (240 ±57 ml/min) did not differ from control subjects. The MCR in eight patients with insulin-independent diabetes mellitus (IID) (185 ±41 ml/min) and in eight patients with insulin-dependent diabetes mellitus (IDD) (136 ±31 ml/min) were significantly different from control subjects (P = < 0.05 and P = < 0.001, respectively). These data were interpreted to indicate that the plasma HGH-removing mechanism(s) is not saturated at physiologic plasma HGH levels, that plasma HGH levels alone may not permit distinction between variations in pituitary release of the hormone and its rate of clearance from the plasma, and that the estimation of the MCR of HGH may help clarify the mechanism of abnormal plasma HGH responses to various stimuli. Production rates of HGH (PR) in control subjects (347 ±173 mμg/min) were contrasted with hyperthyroid patients (529 ±242 mμg/min, P < 0.05), hypothyroid patients (160 ±69 mμg/min, P < 0.02), IID (245 ±100 mμg/min, NS), and IDD (363 ±153 mμg/min, NS). Considerable
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Conceptual Design and Analysis of Orbital Cryogenic Liquid Storage and Supply Systems.
1981-05-01
MCR -79-561, Martin Marietta Corporation, June 1979. 5. Tegart, J. R.: Hydrodynamic Analysis Report - Cryogenic Fluid Management...Experiment, MCR -79-563, Martin Marietta Corporation, June 1979, (Contract NAS3-2 1591). 6. Gille, J. P.: Thermal Analysis Report - Cryogenic Fluid Management...Analysis Report - Cryogenic Fluid Management Experiment, MCR -79-567, Martin Marietta Corporation, June 1979, (Contract NAS3-21591). 8. "Low
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Conductivity Rise During Irreversible Electroporation: True Permeabilization or Heat?
Ruarus, Alette H; Vroomen, Laurien G P H; Puijk, Robbert S; Scheffer, Hester J; Faes, Theo J C; Meijerink, Martijn R
2018-04-23
Irreversible electroporation (IRE) induces apoptosis with high-voltage electric pulses. Although the working mechanism is non-thermal, development of secondary Joule heating occurs. This study investigated whether the observed conductivity rise during IRE is caused by increased cellular permeabilization or heat development. IRE was performed in a gelatin tissue phantom, in potato tubers, and in 30 patients with unresectable colorectal liver metastases (CRLM). Continuous versus sequential pulsing protocols (10-90 vs. 10-30-30-30) were assessed. Temperature was measured using fiber-optic probes. After temperature had returned to baseline, 100 additional pulses were delivered. The primary technique efficacy of the treated CRLM was compared to the periprocedural current rise. Seven patients received ten additional pulses after a 10-min cool-down period. Temperature and current rise was higher for the continuous pulsing protocol (medians, gel: 13.05 vs. 9.55 °C and 9 amperes (A) vs. 7A; potato: 12.70 vs. 10.53 °C and 6.0A vs. 6.5A). After cooling-down, current returned to baseline in the gel phantom and near baseline values (Δ2A with continuous- and Δ5A with sequential pulsing) in the potato tubers. The current declined after cooling-down in all seven patients with CRLM, although baseline values were not reached. There was a positive correlation between current rise and primary technique efficacy (p = 0.02); however, the previously reported current increase threshold of 12-15A was reached in 13%. The observed conductivity rise during IRE is caused by both cellular permeabilization and heat development. Although a correlation between current rise and efficacy exists, the current increase threshold seems unfeasible for CRLM.
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Detection of Sound Rise Time by Adults with Dyslexia
ERIC Educational Resources Information Center
Hamalainen, J.; Leppanen, P.H.T.; Torppa, M.; Muller, K.; Lyytinen, H.
2005-01-01
Low sensitivity to amplitude modulated (AM) sounds is reported to be associated with dyslexia. An important aspect of amplitude modulation cycles are the rise and fall times within the sound. In this study, simplified stimuli equivalent to just one cycle were used and sensitivity to varying rise times was explored. Adult participants with dyslexia…
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Important parameters for smoke plume rise simulation with Daysmoke
L. Liu; G.L. Achtemeier; S.L. Goodrick; W. Jackson
2010-01-01
Daysmoke is a local smoke transport model and has been used to provide smoke plume rise information. It includes a large number of parameters describing the dynamic and stochastic processes of particle upward movement, fallout, fluctuation, and burn emissions. This study identifies the important parameters for Daysmoke simulations of plume rise and seeks to understand...
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Structural and compositional features of high-rise buildings: experimental design in Yekaterinburg
NASA Astrophysics Data System (ADS)
Yankovskaya, Yulia; Lobanov, Yuriy; Temnov, Vladimir
2018-03-01
The study looks at the specifics of high-rise development in Yekaterinburg. High-rise buildings are considered in the context of their historical development, structural features, compositional and imaginative design techniques. Experience of Yekaterinburg architects in experimental design is considered and analyzed. Main issues and prospects of high-rise development within the Yekaterinburg structure are studied. The most interesting and significant conceptual approaches to the structural and compositional arrangement of high-rise buildings are discussed.
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Comparative Study of Microstructure and Properties of Thermal Sprayed MCrAlY Bond Coatings
NASA Astrophysics Data System (ADS)
Inglima, Michael William
A series of experiments were performed in order to observe certain process-property trends in thermally sprayed MCrAlY bond coatings for thermal barrier coating (TBC) applications in gas-turbine engines. Firstly, the basis of gas-turbine operation and design is discussed with a focus on the Brayton cycle and basic thermodynamic properties with respect to both the thermal and fuel efficiency of the turbine. The high-temperature environment inside the gas-turbine engine creates an extremely corrosive medium in which the engineering components must operate with sufficient operating life times. These engineering constraints, both thermal/fuel efficiency and operating life, pose a serious problem during long operation as well as thermal cycling of a civil aerospace engine. The concept of a thermal barrier coating is introduced along with how these coatings protect the internal engineering components, mostly in the hot-section of the turbine, and increase both the efficiency as well as the operating life of the components. The method used to create TBC's is then introduced being thermal spray processing along with standard operating procedures (SOP) used during coating deposition. The main focus of the experiments was to quantify the process-property trends seen during thermal spray processing of TBC's with respect to the adhesion and thermally grown oxide (TGO) layer, as well as how sensitive these properties are to changing variables during coating deposition. The design of experiment (DOE) method was used in order to have sufficient statistical process control over the output as well as a standard method for quantifying the results. A total of three DOE's were performed using two main types of thermal spray processes being high-velocity oxygen fuel (HVOF) and atmospheric plasma spray (APS), with a total of five different types of torches which are categorized by liquid-fuel, gas-fuel, and single cathode plasma. The variables used in the proceeding experiments were
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Hydrothermal germanium over the southern East pacific rise.
Mortlock, R A; Froelich, P N
1986-01-03
Germanium enrichment in the oceanic water column above the southern axis of the East Pacific Rise results from hydrothermal solutions emanating from hot springs along the rise crest. This plume signature provides a new oceanic tracer of reactions between seawater and sea floor basalts during hydrothermal alteration. In contrast to the sharp plumes of (3)He and manganese, the germanium plume is broad and diffuse, suggesting the existence of pervasive venting of low-temperature solutions off the ridge axis.
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Hegazy, Maha A; Abdelwahab, Nada S; Fayed, Ahmed S
2015-04-05
A novel method was developed for spectral resolution and further determination of five-component mixture including Vitamin B complex (B1, B6, B12 and Benfotiamine) along with the commonly co-formulated Diclofenac. The method is simple, sensitive, precise and could efficiently determine the five components by a complementary application of two different techniques. The first is univariate second derivative method that was successfully applied for determination of Vitamin B12. The second is Multivariate Curve Resolution using the Alternating Least Squares method (MCR-ALS) by which an efficient resolution and quantitation of the quaternary spectrally overlapped Vitamin B1, Vitamin B6, Benfotiamine and Diclofenac sodium were achieved. The effect of different constraints was studied and the correlation between the true spectra and the estimated spectral profiles were found to be 0.9998, 0.9983, 0.9993 and 0.9933 for B1, B6, Benfotiamine and Diclofenac, respectively. All components were successfully determined in tablets and capsules and the results were compared to HPLC methods and they were found to be statistically non-significant. Copyright © 2015 Elsevier B.V. All rights reserved.
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Sea-Level Rise and Flood Potential along the California Coast
NASA Astrophysics Data System (ADS)
Delepine, Q.; Leung, C.
2013-12-01
Sea-level rise is becoming an ever-increasing problem in California. Sea-level is expected to rise significantly in the next 100 years, which will raise flood elevations in coastal communities. This will be an issue for private homeowners, businesses, and the state. One study suggests that Venice Beach could lose a total of at least $440 million in tourism spending and tax dollars from flooding and beach erosion if sea level rises 1.4 m by 2100. In addition, several airports, such as San Francisco International Airport, are located in coastal regions that have flooded in the past and will likely be flooded again in the next 30 years, but sea-level rise is expected to worsen the effects of flooding in the coming decades It is vital for coastal communities to understand the risks associated with sea-level rise so that they can plan to adapt to it. By obtaining accurate LiDAR elevation data from the NOAA Digital Coast Website (http://csc.noaa.gov/dataviewer/?keyword=lidar#), we can create flood maps to simulate sea level rise and flooding. The data are uploaded to ArcGIS and contour lines are added for different elevations that represent future coastlines during 100-year flooding. The following variables are used to create the maps: 1. High-resolution land surface elevation data - obtained from NOAA 2. Local mean high water level - from USGS 3. Local 100-year flood water level - from the Pacific Institute 4. Sea-level rise projections for different future dates (2030, 2050, and 2100) - from the National Research Council The values from the last three categories are added to represent sea-level rise plus 100-year flooding. These values are used to make the contour lines that represent the projected flood elevations, which are then exported as KML files, which can be opened in Google Earth. Once these KML files are made available to the public, coastal communities will gain an improved understanding of how flooding and sea-level rise might affect them in the future
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RISE Evaluation and Development System: Student Learning Objectives Handbook
ERIC Educational Resources Information Center
Indiana Department of Education, 2016
2016-01-01
With the help of teachers and leaders throughout the state, the Indiana Department of Education has developed an optional model teacher evaluation system named RISE. Whether corporations choose to adopt RISE or a model of their own, the department's goal is to assist corporations in developing or adopting models that both comply with IC 20-28-11.5…
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Building more effective sea level rise models for coastal management
NASA Astrophysics Data System (ADS)
Kidwell, D.; Buckel, C.; Collini, R.; Meckley, T.
2017-12-01
For over a decade, increased attention on coastal resilience and adaptation to sea level rise has resulted in a proliferation of predictive models and tools. This proliferation has enhanced our understanding of our vulnerability to sea level rise, but has also led to stakeholder fatigue in trying to realize the value of each advancement. These models vary in type and complexity ranging from GIS-based bathtub viewers to modeling systems that dynamically couple complex biophysical and geomorphic processes. These approaches and capabilities typically have the common purpose using scenarios of global and regional sea level change to inform adaptation and mitigation. In addition, stakeholders are often presented a plethora of options to address sea level rise issues from a variety of agencies, academics, and consulting firms. All of this can result in confusion, misapplication of a specific model/tool, and stakeholder feedback of "no more new science or tools, just help me understand which one to use". Concerns from stakeholders have led to the question; how do we move forward with sea level rise modeling? This presentation will provide a synthesis of the experiences and feedback derived from NOAA's Ecological Effects of Sea level Rise (EESLR) program to discuss the future of predictive sea level rise impact modeling. EESLR is an applied research program focused on the advancement of dynamic modeling capabilities in collaboration with local and regional stakeholders. Key concerns from stakeholder engagement include questions about model uncertainty, approaches for model validation, and a lack of cross-model comparisons. Effective communication of model/tool products, capabilities, and results is paramount to address these concerns. Looking forward, the most effective predictions of sea level rise impacts on our coast will be attained through a focus on coupled modeling systems, particularly those that connect natural processes and human response.
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Methyl-coenzyme M reductase A as an indicator to estimate methane production from dairy cows.
Aguinaga Casañas, M A; Rangkasenee, N; Krattenmacher, N; Thaller, G; Metges, C C; Kuhla, B
2015-06-01
The evaluation of greenhouse gas mitigation strategies requires the quantitative assessment of individual methane production. Because methane measurement in respiration chambers is highly accurate, but also comprises various disadvantages such as limited capacity and high costs, the establishment of an indicator for estimating methane production of individual ruminants would provide an alternative to direct methane measurement. Methyl-coenzyme M reductase is involved in methanogenesis and the subunit α of methyl-coenzyme M reductase is encoded by the mcrA gene of rumen archaea. We therefore examined the relationship between methane emissions of Holstein dairy cows measured in respiration chambers with 2 different diets (high- and medium-concentrate diet) and the mcrA DNA and mcrA cDNA abundance determined from corresponding rumen fluid samples. Whole-body methane production per kilogram of dry matter intake and mcrA DNA normalized to the abundance of the rrs gene coding for 16S rRNA correlated significantly when using qmcrA primers. Use of qmcrA primers also revealed linear correlation between mcrA DNA copy number and methane yield. Regression analyses based on normalized mcrA cDNA abundances revealed no significant linear correlation with methane production per kilogram of dry matter intake. Furthermore, the correlations between normalized mcrA DNA abundance and the rumen fluid concentration of acetic and isobutyric acid were positive, whereas the correlations with propionic and lactic acid were negative. These data suggest that the mcrA DNA approach based on qmcrA primers could potentially be a molecular proxy for methane yield after further refinement. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
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Coastal vulnerability assessment of Olympic National Park to sea-level rise
Pendleton, Elizabeth A.; Hammar-Klose, Erika S.; Thieler, E. Robert; Williams, S. Jeffress
2004-01-01
A coastal vulnerability index (CVI) was used to map the relative vulnerability of the coast to future sea-level rise within Olympic National Park (OLYM), Washington. The CVI scores the following in terms of their physical contribution to sea-level rise-related coastal change: geomorphology, regional coastal slope, rate of relative sea-level rise, shoreline change rates, mean tidal range and mean wave height. The rankings for each variable were combined and an index value calculated for 1-minute grid cells covering the park. The CVI highlights those regions where the physical effects of sea-level rise might be the greatest. This approach combines the coastal system's susceptibility to change with its natural ability to adapt to changing environmental conditions, yielding a quantitative, although relative, measure of the park's natural vulnerability to the effects of sea-level rise. The CVI provides an objective technique for evaluation and long-term planning by scientists and park managers. The Olympic National Park coast consists of rocky headlands, pocket beaches, glacial-fluvial features, and sand and gravel beaches. The Olympic coastline that is most vulnerable to sea-level rise are beaches in gently sloping areas.
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[Transformer winding's temperature rising and an analysis of its uncertainty].
Wang, Pei-Lian; Chen, Yu-En; Zhong, Sheng-Kui
2007-09-01
This paper introduces the temperature rising experimental process and some matters needing attention when the transformer is normally loading. And an analysis of the uncertainty for transformer's temperature rising is also made based on the practical examples' data.
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Güzel, Fuat; Yakut, Hakan; Topal, Giray
2008-05-30
In this study, the effect of temperature on the adsorption of Mn(II), Ni(II), Co(II) and Cu(II) from aqueous solution by modified carrot residues (MCR) was investigated. The equilibrium contact times of adsorption process for each heavy metals-MCR systems were determined. Kinetic data obtained for each heavy metal by MCR at different temperatures were applied to the Lagergren equation, and adsorption rate constants (kads) at these temperatures were determined. These rate constants related to the adsorption of heavy metal by MCR were applied to the Arrhenius equation, and activation energies (Ea) were determined. In addition, the isotherms for adsorption of each heavy metal by MCR at different temperatures were also determined. These isothermal data were applied to linear forms of isotherm equations that they fit the Langmuir adsorption isotherm, and the Langmuir constants (qm and b) were calculated. b constants determined at different temperatures were applied to thermodynamic equations, and thermodynamic parameters such as enthalpy (Delta H), free energy (Delta G), and entropy (Delta S) were calculated and these values show that adsorption of heavy metal on MCR was an endothermic process and process of adsorption was favoured at high temperatures.
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NASA Astrophysics Data System (ADS)
Yan, Rongge; Guo, Xiaoting; Cao, Shaoqing; Zhang, Changgeng
2018-05-01
Magnetically coupled resonance (MCR) wireless power transfer (WPT) system is a promising technology in electric energy transmission. But, if its system parameters are designed unreasonably, output power and transmission efficiency will be low. Therefore, optimized parameters design of MCR WPT has important research value. In the MCR WPT system with designated coil structure, the main parameters affecting output power and transmission efficiency are the distance between the coils, the resonance frequency and the resistance of the load. Based on the established mathematical model and the differential evolution algorithm, the change of output power and transmission efficiency with parameters can be simulated. From the simulation results, it can be seen that output power and transmission efficiency of the two-coil MCR WPT system and four-coil one with designated coil structure are improved. The simulation results confirm the validity of the optimization method for MCR WPT system with designated coil structure.
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Rising ground-water level in downtown Louisville, Kentucky, 1972-1977
Kernodle, J.M.; Whitesides, D.V.
1977-01-01
Ground-water levels in the alluvial aquifer in Louisville, Jefferson County, Kentucky, are rising at a rate which could cause wet basements and possible structural damage tc buildings in the downtown area by 1982. The predicted water level for 1982 is based on the nearly linear increase which has been observed from 1972 to 1977, during which period a rise of as much as 32 feet was recorded in water-level observation wells. Foremost among the possible causes of the rise is a decrease in withdrawal of ground water.
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Space-planning and structural solutions of low-rise buildings: Optimal selection methods
NASA Astrophysics Data System (ADS)
Gusakova, Natalya; Minaev, Nikolay; Filushina, Kristina; Dobrynina, Olga; Gusakov, Alexander
2017-11-01
The present study is devoted to elaboration of methodology used to select appropriately the space-planning and structural solutions in low-rise buildings. Objective of the study is working out the system of criteria influencing the selection of space-planning and structural solutions which are most suitable for low-rise buildings and structures. Application of the defined criteria in practice aim to enhance the efficiency of capital investments, energy and resource saving, create comfortable conditions for the population considering climatic zoning of the construction site. Developments of the project can be applied while implementing investment-construction projects of low-rise housing at different kinds of territories based on the local building materials. The system of criteria influencing the optimal selection of space-planning and structural solutions of low-rise buildings has been developed. Methodological basis has been also elaborated to assess optimal selection of space-planning and structural solutions of low-rise buildings satisfying the requirements of energy-efficiency, comfort and safety, and economical efficiency. Elaborated methodology enables to intensify the processes of low-rise construction development for different types of territories taking into account climatic zoning of the construction site. Stimulation of low-rise construction processes should be based on the system of approaches which are scientifically justified; thus it allows enhancing energy efficiency, comfort, safety and economical effectiveness of low-rise buildings.
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MRO's High Resolution Imaging Science Experiment (HiRISE) Education And Public Outreach program
NASA Astrophysics Data System (ADS)
Gulick, V. C.; Davatzes, A.; McEwen, A.
2006-12-01
HiRISE provides an innovative education and public outreach program with a variety of formal and informal educational activities. The centerpiece of HiRISE's E/PO program is it's interactive website called HiWeb (http://marsoweb.nasa.nasa.gov/hirise and http://hirise.lpl.arizona.edu). HiWeb provides an image suggestion facility where the public can submit suggestions for HiRISE images and view HiRISE images in context with other available Mars data. HiRISE EPO has developed K-14 educational materials including activity, coloring and comic books that focus on Mars geology, the image suggestion process, understanding the HiRISE camera and working with digital image data. In addition, we have developed interactive educational games including Mars crosswords, jigsaws, word searches, and flash cards to provide fun ways for students to learn more about Mars. All educational materials and games are aligned with the National Science Standards. HiRISE Clickworkers will provide online opportunities for the public to assist the team in creating geologic feature databases (gullies, boulders, craters, wind streaks, etc.) present in the HiRISE images in addition to other innovative opportunities. Web events (including web chats, casts and forums) with HiRISE team members, will help guide students and educators of HiRISE capabilities and science goals and provide support for submitting good image suggestions. Educator workshops will be held each year at or near the institution of HiRISE team members. Workshop support materials and instructions for all hands-on activities will be placed on HiWeb to facilitate sharing of information with other educators and the general public. Large-scale displays of HiRISE images will be available at several at museums and planetariums.
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ERIC Educational Resources Information Center
Piva, M.
2009-01-01
In introductory-level physics courses, the concept of surface tension is often illustrated using the example of capillary rise in thin tubes. In this paper the author describes experiments conducted using a planar geometry created with two small plates forming a thin wedge. The distribution of the fluid entering the wedge can be studied as a…
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ERIC Educational Resources Information Center
Lum, Lydia
2005-01-01
This article reports on the growth of blogs in popular culture, and the fact that they are becoming more widely accepted in the media industry. The rise and popularity of blogs--short for "Web logs"--are causing journalism educators to overhaul their teachings. In fact, blogging's influence varies from one university program to the next, just like…
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Helping Students Rise and Shine
ERIC Educational Resources Information Center
Ross, Flynn; Gendron, Marcia; Nogar, Dan; Queen, Marjorie
2018-01-01
A high-poverty, previously low-performing elementary school in Maine shifted its from looking mainly at achievement and test scores to focusing on ways to create motivated, confident, engaged students. They created Rise and Shine, through which all 3rd-5th graders start each day with a fun, challenging activity chosen from a big menu--from…
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ERIC Educational Resources Information Center
Umpstead, Bruce
2009-01-01
This article discusses the rise of online learning and describes how educators in Michigan are doing their part to harness the power of online learning to transform today's high school students into lifelong learners, a key component of students' long-term success in the global economy. The author urges schools to prepare for the growing demand in…
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PERSPECTIVE: The tripping points of sea level rise
NASA Astrophysics Data System (ADS)
Hecht, Alan D.
2009-12-01
When President Nixon created the US Environmental Protection Agency (EPA) in 1970 he said the environment must be perceived as a single, interrelated system. We are nowhere close to achieving this vision. Jim Titus and his colleagues [1] highlight one example of where one set of regulations or permits may be in conflict with another and where regulations were crafted in the absence of understanding the cumulative impact of global warming. The issue here is how to deal with the impacts of climate change on sea level and the latter's impact on wetland polices, clean water regulations, and ecosystem services. The Titus paper could also be called `The tripping points of sea level rise'. Titus and his colleagues have looked at the impact of such sea level rise on the east coast of the United States. Adaptive responses include costly large- scale investment in shore protection (e.g. dikes, sand replenishment) and/or ecosystem migration (retreat), where coastal ecosystems move inland. Shore protection is limited by available funds, while ecosystem migrations are limited by available land use. The driving factor is the high probability of sea level rise due to climate change. Estimating sea level rise is difficult because of local land and coastal dynamics including rising or falling land areas. It is estimated that sea level could rise between 8 inches and 2 feet by the end of this century [2]. The extensive data analysis done by Titus et al of current land use is important because, as they observe, `property owners and land use agencies have generally not decided how they will respond to sea level rise, nor have they prepared maps delineating where shore protection and retreat are likely'. This is the first of two `tripping points', namely the need for adaptive planning for a pending environmental challenge that will create economic and environment conflict among land owners, federal and state agencies, and businesses. One way to address this gap in adaptive management
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Comment [on “Sea level rise shown to drive coastal erosion”
Pilkey, Orrin H.; Young, Robert S.; Bush, David M.
2000-01-01
Leatherman et al. [2000] (Eos, Trans., AGU, February 8, 2000, p.55) affirm that global eustatic sea-level rise is driving coastal erosion. Furthermore, they argue that the long-term average rate of shoreline retreat is 150 times the rate of sea-level rise. This rate, they say, is more than a magnitude greater than would be expected from a simple response to sea-level rise through inundation of the shoreline. We agree that sea-level rise is the primary factor causing shoreline retreat in stable coastal areas.This is intuitive. We also believe, however, that the Leatherman et al. [2000] study has greatly underestimated the rate of coastal recession along most low slope shorelines. Slopes along the North Carolina continental shelf/coastal plain approach 10,000:1. To us, this suggests that we should expect rates of shoreline recession 10,000 times the rate of sea-level rise through simple inundation of the shoreline.
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Gravitational salt tectonics above a rising basement plateau offshore Algeria
NASA Astrophysics Data System (ADS)
Gaullier, Virginie; Vendeville, Bruno C.; Besème, Grégoire; Legoux, Gaetan; Déverchère, Jacques; Lymer, Gaël
2017-04-01
Seismic data (survey "MARADJA 1", 2003) offshore the Algerian coast have imaged an unexpected deformation pattern of the Messinian salt (Mobile Unit; MU) and its sedimentary overburden (Messinian Upper Unit and Plio-Quaternary) above an actively rising plateau in the subsalt basement. From a geodynamic point of view, the region is undergoing crustal convergence, as attested by the Boumerdes earthquake (2003, magnitude 6.8). The rise of this plateau, forming a 3D promontory restricted to the area offshore Algiers, is associated with that geodynamic setting. The seismic profiles show several subsalt thrusts (Domzig et al. 2006). The data provided additional information on the deformation of the Messinian mobile evaporitic unit and its Plio-Quaternary overburden. Margin-perpendicular profiles show mostly compressional features (anticlines and synclines) that had little activity during Messinian times, then grew more during Plio-Quaternary times. A few normal faults are also present, but are not accompanied by salt rise. By contrast, margin-parallel profiles clearly show that extensional, reactive salt diapiric ridges (symptomatic with their triangular shape in cross section) formed early, as early as the time of deposition of the Messinian Upper Unit, as recorded by fan-shaped strata. These ridges have recorded E-W, thin-skinned gravity gliding above the Messinian salt, as a response to the rise of the basement plateau. We tested this hypothesis using two analogue models, one where we assumed that the rise of the plateau started after Messinian times (initially tabular salt across the entire region), the second model assumed that the plateau had already risen partially as the Messininan Mobile Unit was deposited (salt initially thinner above the plateau than in the adjacent regions). In both experiments, the rise of the plateau generated preferential E-W extension above the salt, combined with N-S shortening. Extension was caused by gravity gliding of the salt from
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Sea-level rise caused by climate change and its implications for society
MIMURA, Nobuo
2013-01-01
Sea-level rise is a major effect of climate change. It has drawn international attention, because higher sea levels in the future would cause serious impacts in various parts of the world. There are questions associated with sea-level rise which science needs to answer. To what extent did climate change contribute to sea-level rise in the past? How much will global mean sea level increase in the future? How serious are the impacts of the anticipated sea-level rise likely to be, and can human society respond to them? This paper aims to answer these questions through a comprehensive review of the relevant literature. First, the present status of observed sea-level rise, analyses of its causes, and future projections are summarized. Then the impacts are examined along with other consequences of climate change, from both global and Japanese perspectives. Finally, responses to adverse impacts will be discussed in order to clarify the implications of the sea-level rise issue for human society. PMID:23883609
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Climate Adaptation and Sea Level Rise
EPA supports the development and maintenance of water utility infrastructure across the country. Included in this effort is helping the nation’s water utilities anticipate, plan for, and adapt to risks from flooding, sea level rise, and storm surge.
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Population dynamics of Hawaiian seabird colonies vulnerable to sea-level rise
Hatfield, Jeff S.; Reynolds, Michelle H.; Seavy, Nathaniel E.; Krause, Crystal M.
2012-01-01
Globally, seabirds are vulnerable to anthropogenic threats both at sea and on land. Seabirds typically nest colonially and show strong fidelity to natal colonies, and such colonies on low-lying islands may be threatened by sea-level rise. We used French Frigate Shoals, the largest atoll in the Hawaiian Archipelago, as a case study to explore the population dynamics of seabird colonies and the potential effects sea-level rise may have on these rookeries. We compiled historic observations, a 30-year time series of seabird population abundance, lidar-derived elevations, and aerial imagery of all the islands of French Frigate Shoals. To estimate the population dynamics of 8 species of breeding seabirds on Tern Island from 1980 to 2009, we used a Gompertz model with a Bayesian approach to infer population growth rates, density dependence, process variation, and observation error. All species increased in abundance, in a pattern that provided evidence of density dependence. Great Frigatebirds (Fregata minor), Masked Boobies (Sula dactylatra), Red-tailed Tropicbirds (Phaethon rubricauda), Spectacled Terns (Onychoprion lunatus), and White Terns (Gygis alba) are likely at carrying capacity. Density dependence may exacerbate the effects of sea-level rise on seabirds because populations near carrying capacity on an island will be more negatively affected than populations with room for growth. We projected 12% of French Frigate Shoals will be inundated if sea level rises 1 m and 28% if sea level rises 2 m. Spectacled Terns and shrub-nesting species are especially vulnerable to sea-level rise, but seawalls and habitat restoration may mitigate the effects of sea-level rise. Losses of seabird nesting habitat may be substantial in the Hawaiian Islands by 2100 if sea levels rise 2 m. Restoration of higher-elevation seabird colonies represent a more enduring conservation solution for Pacific seabirds.
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State of the Carbon Cycle - Consequences of Rising Atmospheric CO2
NASA Astrophysics Data System (ADS)
Moore, D. J.; Cooley, S. R.; Alin, S. R.; Brown, M. E.; Butman, D. E.; French, N. H. F.; Johnson, Z. I.; Keppel-Aleks, G.; Lohrenz, S. E.; Ocko, I.; Shadwick, E. H.; Sutton, A. J.; Potter, C. S.; Yu, R. M. S.
2016-12-01
The rise of atmospheric CO2, largely attributable to human activity through fossil fuel emissions and land-use change, has been dampened by carbon uptake by the ocean and terrestrial biosphere. We outline the consequences of this carbon uptake as direct and indirect effects on terrestrial and oceanic systems and processes for different regions of North America and the globe. We assess the capacity of these systems to continue to act as carbon sinks. Rising CO2 has decreased seawater pH; this process of ocean acidification has impacted some marine species and altered fundamental ecosystem processes with further effects likely. In terrestrial ecosystems, increased atmospheric CO2 causes enhanced photosynthesis, net primary production, and increased water-use efficiency. Rising CO2 may change vegetation composition and carbon storage, and widespread increases in water use efficiency likely influence terrestrial hydrology and biogeochemical cycling. Consequences for human populations include changes to ecosystem services including cultural activities surrounding land use, agricultural or harvesting practices. Commercial fish stocks have been impacted and crop production yields have been changed as a result of rising CO2. Ocean and terrestrial effects are contingent on, and feedback to, global climate change. Warming and modified precipitation regimes impact a variety of ecosystem processes, and the combination of climate change and rising CO2 contributes considerable uncertainty to forecasting carbon sink capacity in the ocean and on land. Disturbance regime (fire and insects) are modified with increased temperatures. Fire frequency and intensity increase, and insect lifecycles are disrupted as temperatures move out of historical norms. Changes in disturbance patterns modulate the effects of rising CO2 depending on ecosystem type, disturbance frequency, and magnitude of events. We discuss management strategies designed to limit the rise of atmospheric CO2 and reduce
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State of the Carbon Cycle - Consequences of Rising Atmospheric CO2
NASA Technical Reports Server (NTRS)
Moore, David J.; Cooley, Sarah R.; Alin, Simone R.; Brown, Molly; Butman, David E.; French, Nancy H. F.; Johnson, Zackary I.; Keppel-Aleks; Lohrenz, Steven E.; Ocko, Ilissa;
2016-01-01
The rise of atmospheric CO2, largely attributable to human activity through fossil fuel emissions and land-use change, has been dampened by carbon uptake by the ocean and terrestrial biosphere. We outline the consequences of this carbon uptake as direct and indirect effects on terrestrial and oceanic systems and processes for different regions of North America and the globe. We assess the capacity of these systems to continue to act as carbon sinks. Rising CO2 has decreased seawater pH; this process of ocean acidification has impacted some marine species and altered fundamental ecosystem processes with further effects likely. In terrestrial ecosystems, increased atmospheric CO2 causes enhanced photosynthesis, net primary production, and increased water-use efficiency. Rising CO2 may change vegetation composition and carbon storage, and widespread increases in water use efficiency likely influence terrestrial hydrology and biogeochemical cycling. Consequences for human populations include changes to ecosystem services including cultural activities surrounding land use, agricultural or harvesting practices. Commercial fish stocks have been impacted and crop production yields have been changed as a result of rising CO2. Ocean and terrestrial effects are contingent on, and feedback to, global climate change. Warming and modified precipitation regimes impact a variety of ecosystem processes, and the combination of climate change and rising CO2 contributes considerable uncertainty to forecasting carbon sink capacity in the ocean and on land. Disturbance regime (fire and insects) are modified with increased temperatures. Fire frequency and intensity increase, and insect lifecycles are disrupted as temperatures move out of historical norms. Changes in disturbance patterns modulate the effects of rising CO2 depending on ecosystem type, disturbance frequency, and magnitude of events. We discuss management strategies designed to limit the rise of atmospheric CO2 and reduce
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Lunar breccias, petrology, and earth planetary structure
NASA Technical Reports Server (NTRS)
Ridley, W. I.
1978-01-01
Topics covered include: (1) petrologic studies of poikiloblastic textured rocks; (2) petrology of aluminous mare basalts in breccia 14063; (3) petrology of Apollo 15 breccia 15459; (4) high-alumina mare basalts; (5) some petrological aspects of imbrium stratigraphy; (6) petrology of lunar rocks and implication to lunar evolution; (7) the crystallization trends of spinels in Tertiary basalts from Rhum and Muck and their petrogenetic significance; (8) the geology and evolution of the Cayman Trench; (9) The petrochemistry of igneous rocks from the Cayman Trench and the Captains Bay Pluton, Unalaska Island and their relation to tectonic processes at plate margins; and (10) the oxide and silicate mineral chemistry of a Kimberlite from the Premier Mine with implications for the evolution of kimberlitic magma.
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Gardening as vector of a humanization of high-rise building
NASA Astrophysics Data System (ADS)
Lekareva, Nina; Zaslavskaya, Anna
2018-03-01
Article is devoted to issue of integration of vertical gardening into structure of high-rise building in the conditions of the constrained town-planning situation. On the basis of the analysis of the existing experience of design and building of "biopositive" high-rise building ecological, town-planning, social and constructive advantages of the organization of gardens on roofs and vertical gardens are considered [1]. As the main mechanism of increase in investment appeal of high-rise building the principle of a humanization due to gardening of high-rise building taking into account requirements of ecology, energy efficiency of buildings and improvement of quality of construction with minimization of expenses and maximizing comfort moves forward. The National Standards of Green construction designed to adapt the international requirements of architecture and construction of the energy efficient, eco-friendly and comfortable building or a complex to local conditions are considered [2,3].
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Agriculture waste and rising CO2
USDA-ARS?s Scientific Manuscript database
Currently, there are many uncertainties concerning agriculture’s role in global environmental change including the effects of rising atmospheric CO2 concentration. A viable and stable world food supply depends on productive agricultural systems, but environmental concerns within agriculture have to...
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Rising sea level may cause decline of fringing coral reefs
Field, Michael E.; Ogston, Andrea S.; Storlazzi, Curt D.
2011-01-01
Coral reefs are major marine ecosystems and critical resources for marine diversity and fisheries. These ecosystems are widely recognized to be at risk from a number of stressors, and added to those in the past several decades is climate change due to anthropogenically driven increases in atmospheric concentrations of greenhouse gases. Most threatening to most coral reefs are elevated sea surface temperatures and increased ocean acidity [e.g., Kleypas et al., 1999; Hoegh-Guldberg et al., 2007], but sea level rise, another consequence of climate change, is also likely to increase sedimentary processes that potentially interfere with photosynthesis, feeding, recruitment, and other key physiological processes (Figure 1). Anderson et al. [2010] argue compellingly that potential hazardous impacts to coastlines from 21st-century sea level rise are greatly underestimated, particularly because of the rapid rate of rise. The Intergovernmental Panel on Climate Change estimates that sea level will rise in the coming century (1990–2090) by 2.2–4.4 millimeters per year, when projected with little contribution from melting ice [Meehl et al., 2007]. New studies indicate that rapid melting of land ice could substantially increase the rate of sea level rise [Grinsted et al., 2009; Milne et al., 2009].
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Analysis of Sea Level Rise in Singapore Strait
NASA Astrophysics Data System (ADS)
Tkalich, Pavel; Luu, Quang-Hung
2013-04-01
Sea level in Singapore Strait is governed by various scale phenomena, from global to local. Global signals are dominated by the climate change and multi-decadal variability and associated sea level rise; at regional scale seasonal sea level variability is caused by ENSO-modulated monsoons; locally, astronomic tides are the strongest force. Tide gauge records in Singapore Strait are analyzed to derive local sea level trend, and attempts are made to attribute observed sea level variability to phenomena at various scales, from global to local. It is found that at annual scale, sea level anomalies in Singapore Strait are quasi-periodic, of the order of ±15 cm, the highest during northeast monsoon and the lowest during southwest monsoon. Interannual regional sea level falls are associated with El Niño events, while the rises are related to La Niña episodes; both variations are in the range of ±9 cm. At multi-decadal scale, sea level in Singapore Strait has been rising at the rate 1.2-1.9 mm/year for the period 1975-2009, 2.0±0.3 mm/year for 1984-2009, and 1.3-4.7 mm/year for 1993-2009. When compared with the respective global trends of 2.0±0.3, 2.4, and 2.8±0.8 mm/year, Singapore Strait sea level rise trend was weaker at the earlier period and stronger at the recent decade.
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Maternal care receptivity and its relation to perinatal and neonatal mortality. A rural study.
Bhardwaj, N; Hasan, S B; Zaheer, M
1995-04-01
A longitudinal study was conducted on 212 pregnant women from May 1987 to April 1988. Maternal Care Receptivity (MCR) "an innovative approach" was adopted for the assessment of maternal care services provided to pregnant mothers at their door steps. During follow-up, scores were allotted to each of the services rendered and antenatal status of pregnant women. Depending on the score--MCR was classified as high (11 to 8), moderate (7 to 4) or poor (3 to 0). Perinatal and neonatal deaths were recorded and an inverse relationship between MCR and perinatal and mortalities was observed (z = 5.46, p < 0.0001). Significantly, no perinatal or neonatal deaths occurred in women with high MCR. One of the most important cause of high PNMR and neonatal mortality rate in developing countries is poor MCR, i.e., under utilization of even the existing maternal health services. The main reasons for this under utilization appear to be poverty, illiteracy, ignorance and lack of faith in modern medicine.
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NASA Astrophysics Data System (ADS)
Li, Qian; Tang, Yongjiao; Yan, Zhiwei; Zhang, Pudun
2017-06-01
Although multivariate curve resolution (MCR) has been applied to the analysis of Fourier transform infrared (FTIR) imaging, it is still problematic to determine the number of components. The reported methods at present tend to cause the components of low concentration missed. In this paper a new idea was proposed to resolve this problem. First, MCR calculation was repeated by increasing the number of components sequentially, then each retrieved pure spectrum of as-resulted MCR component was directly compared with a real-world pixel spectrum of the local high concentration in the corresponding MCR map. One component was affirmed only if the characteristic bands of the MCR component had been included in its pixel spectrum. This idea was applied to attenuated total reflection (ATR)/FTIR mapping for identifying the trace additives in blind polymer materials and satisfactory results were acquired. The successful demonstration of this novel approach opens up new possibilities for analyzing additives in polymer materials.
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Sea-level Rise Impacts on Oregon Estuaries: Biology and Hydrology
Estuaries are transitional ecosystems located at the margin of the land and ocean and as a result they are particularly sensitive to sea level rise and other climate drivers. In this presentation, we summarize the potential impacts of sea level rise on key estuarine habitats inc...
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The Enigma of Mercury's Northern Rise
NASA Astrophysics Data System (ADS)
James, P. B.
2018-05-01
Various aspects of the "northern rise" make it hard to explain: Its composition and chronology don't stand out from its surroundings, it seems to have uplifted late, and it has a huge gravity anomaly. We'll discuss the possible formation mechanisms.
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MRO's HiRISE Education and Public Outreach during the Primary Science Phase
NASA Astrophysics Data System (ADS)
Gulick, V. C.; Davatzes, A. K.; Deardorff, G.; Kanefsky, B.; Conrad, L. B.; HiRISE Team
2008-12-01
Looking back over one Mars year, we report on the accomplishments of the HiRISE EPO program during the primary science phase of MRO. A highlight has been our student image suggestion program, conducted in association with NASA Quest as HiRISE Image Challenges (http://quest.arc.nasa.gov/challenges/hirise/). During challenges, students, either individually or as part of a collaborative classroom or group, learn about Mars through our webcasts, web chats and our educational material. They use HiWeb, HiRISE's image suggestion facility, to submit image suggestions and include a short rationale for why their target is scientifically interesting. The HiRISE team gives priority to obtaining a sampling of these suggestions as quickly as possible so that the acquired images can be examined by the students. During the challenge, a special password-protected web site allows participants to view their returned images before they are released to the public (http://marsoweb.nas.nasa.gov/hirise/quest/). Students are encouraged to write captions for the returned images. Finished captions are then posted and highlighted on the HiRISE web site (http://hirise.lpl.arizona.edu) along with their class, teacher's name and the name of their school. Through these HiRISE challenges, students and teachers become virtual science team members, participating in the same process (selecting and justifying targets, analyzing and writing captions for acquired images), and using the same software tools as the HiRISE team. Such an experience is unique among planetary exploration EPO programs. To date, we have completed three HiRISE challenges and a fourth is currently ongoing. More than 200 image suggestions were submitted during the previous challenges and over 85 of these image requests have been acquired so far. Over 675 participants from 45 states and 42 countries have registered for the previous challenges. These participants represent over 8000 students in grades 2 through 14 and consist
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US Military Aircraft Cost Handbook.
1983-03-01
authority 20. ABSIRACr (Coctinus -,e rve.,. afaw it ncvaea7y ad Identifiy by block number) ... Management Consulting & Research, Inc. ( MCR ) collected...methodology is called TASCFORM-AIR. Management Consulting & Research, Inc. ( MCR ) uner subcontracto-assist in this effort, has developed the US...expanded. This edition was produced as part of the current TASC/ MCR effort for OSD Net Assessment to build on the earlier cost-performance work conducted
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Bifurcation of the Kuroshio Extension at the Shatsky Rise
NASA Astrophysics Data System (ADS)
Hurlburt, Harley E.; Metzger, E. Joseph
1998-04-01
A 1/16° six-layer Pacific Ocean model north of 20°S is used to investigate the bifurcation of the Kuroshio Extension at the main Shatsky Rise and the pathway of the northern branch from the bifurcation to the subarctic front. Upper ocean-topographic coupling via a mixed barotropic-baroclinic instability is essential to this bifurcation and to the formation and mean pathway of the northern branch as are several aspects of the Shatsky Rise complex of topography and the latitude of the Kuroshio Extension in relation to the topography. The flow instabilities transfer energy to the abyssal layer where it is constrained by geostrophic contours of the bottom topography. The topographically constrained abyssal currents in turn steer upper ocean currents, which do not directly impinge on the bottom topography. This includes steering of mean pathways. Obtaining sufficient coupling requires very fine resolution of mesoscale variability and sufficient eastward penetration of the Kuroshio as an unstable inertial jet. Resolution of 1/8° for each variable was not sufficient in this case. The latitudinal extent of the main Shatsky Rise (31°N-36°N) and the shape of the downward slope on the north side are crucial to the bifurcation at the main Shatsky Rise, with both branches passing north of the peak. The well-defined, relatively steep and straight eastern edge of the Shatsky Rise topographic complex (30°N-42°N) and the southwestward abyssal flow along it play a critical role in forming the rest of the Kuroshio northern branch which flows in the opposite direction. A deep pass between the main Shatsky Rise and the rest of the ridge to the northeast helps to link the northern fork of the bifurcation at the main rise to the rest of the northern branch. Two 1/16° "identical twin" interannual simulations forced by daily winds 1981-1995 show that the variability in this region is mostly nondeterministic on all timescales that could be examined (up to 7 years in these 15-year
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The complex reality of sea-level rise in an atoll nation
NASA Astrophysics Data System (ADS)
Donner, S. D.
2012-12-01
Sea-level rise famously poses an existential threat to island nations like Kiribati, Tuvalu and the Maldives. Yet as the global mean sea-level rises, the response of any one location at any given time will depend on the natural variability in regional sea-level and other impact of local human activities on coastal processes. As with climate warming, the state of an individual shoreline or the extent of flooding on a given day is not proof of a sea-level trend, nor is a global sea-level trend a good predictor of individual flooding or erosion events. Failure to consider the effect of natural variability and local human activity on coastal processes often leads to misattribution of flooding events and even some long-term shoreline changes to global sea level rise. Moreover, unverified attribution of individual events or changes to specific islets to sea level rise can inflame or invite scepticism of the strong scientific evidence for an accelerating increase in the global sea level due to the impacts of human activity on the climate system. This is particularly important in developing nations like Kiribati, which are depending on international financial support to adapt to rising sea levels. In this presentation, I use gauge data and examples from seven years of field work in Tarawa Atoll, the densely populated capital of Kiribati, to examine the complexity of local sea level and shoreline change in one of the world's most vulnerable countries. First, I discuss how the combination of El Nino-driven variability in sea-level and the astronomical tidal cycle leads to flooding and erosion events which can be mistaken for evidence of sea-level rise. Second, I show that human modification to shorelines has redirected sediment supply, leading, in some cases, to expansion of islets despite rising sea levels. Taken together, the analysis demonstrates the challenge of attributing particular coastal events to global mean sea-level rise and the impact on decision-making. The
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Batiza, Rodey; Oestrike, Richard; Futa, Kiyoto
1982-01-01
The dredges from the East Pacific Rise at about 10°S recovered unusual transitional, light rare-earth element (LREE) enriched basalts which show a range of fractionation. On the basis of their chemical and isotopic abundances, it is unlikely that the lavas are related by a single simple process of magmatic differentiation. We suggest that the mantle source region of these basalts was chemically and isotopically heterogeneous. The chemistry of LREE-depleted tholeiitic basalt dredged from near the axis of the extinct Galapagos Rise indicates complex petrogenesis and differentiation. The presence of tholeiitic basalts here indicates that unlike the Guadalupe and Mathematician fossil ridges, the Galapagos Rise has not been the site of voluminous post-abandonment alkalic volcanism. Alkalic basalts of picritic bulk composition dredged from an elongate seamount near the Galapagos Rise do not represent liquid compositions. Instead, we suggest that these alkalic liquids contain added olivine and plagioclase xenocrysts. Although most of the samples analyzed are very fresh, a few have been altered. The latter exhibit characteristic chemical and isotopic effects of seawater alteration.
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Sea-level rise caused by climate change and its implications for society.
Mimura, Nobuo
2013-01-01
Sea-level rise is a major effect of climate change. It has drawn international attention, because higher sea levels in the future would cause serious impacts in various parts of the world. There are questions associated with sea-level rise which science needs to answer. To what extent did climate change contribute to sea-level rise in the past? How much will global mean sea level increase in the future? How serious are the impacts of the anticipated sea-level rise likely to be, and can human society respond to them? This paper aims to answer these questions through a comprehensive review of the relevant literature. First, the present status of observed sea-level rise, analyses of its causes, and future projections are summarized. Then the impacts are examined along with other consequences of climate change, from both global and Japanese perspectives. Finally, responses to adverse impacts will be discussed in order to clarify the implications of the sea-level rise issue for human society.(Communicated by Kiyoshi HORIKAWA, M.J.A.).
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Estimating Temperature Rise Due to Flashlamp Heating Using Irreversible Temperature Indicators
NASA Technical Reports Server (NTRS)
Koshti, Ajay M.
1999-01-01
One of the nondestructive thermography inspection techniques uses photographic flashlamps. The flashlamps provide a short duration (about 0.005 sec) heat pulse. The short burst of energy results in a momentary rise in the surface temperature of the part. The temperature rise may be detrimental to the top layer of the part being exposed. Therefore, it is necessary to ensure the nondestructive nature of the technique. Amount of the temperature rise determines whether the flashlamp heating would be detrimental to the part. A direct method for the temperature measurement is to use of an infrared pyrometer that has much shorter response time than the flash duration. In this paper, an alternative technique is given using the irreversible temperature 'indicators. This is an indirect technique and it measures the temperature rise on the irreversible temperature indicators and computes the incident heat flux. Once the heat flux is known, the temperature rise on the part can be computed. A wedge shaped irreversible temperature indicator for measuring the heat flux is proposed. A procedure is given to use the wedge indicator.
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A Bayesian network to predict coastal vulnerability to sea level rise
Gutierrez, B.T.; Plant, N.G.; Thieler, E.R.
2011-01-01
Sea level rise during the 21st century will have a wide range of effects on coastal environments, human development, and infrastructure in coastal areas. The broad range of complex factors influencing coastal systems contributes to large uncertainties in predicting long-term sea level rise impacts. Here we explore and demonstrate the capabilities of a Bayesian network (BN) to predict long-term shoreline change associated with sea level rise and make quantitative assessments of prediction uncertainty. A BN is used to define relationships between driving forces, geologic constraints, and coastal response for the U.S. Atlantic coast that include observations of local rates of relative sea level rise, wave height, tide range, geomorphic classification, coastal slope, and shoreline change rate. The BN is used to make probabilistic predictions of shoreline retreat in response to different future sea level rise rates. Results demonstrate that the probability of shoreline retreat increases with higher rates of sea level rise. Where more specific information is included, the probability of shoreline change increases in a number of cases, indicating more confident predictions. A hindcast evaluation of the BN indicates that the network correctly predicts 71% of the cases. Evaluation of the results using Brier skill and log likelihood ratio scores indicates that the network provides shoreline change predictions that are better than the prior probability. Shoreline change outcomes indicating stability (-1 1 m/yr) was not well predicted. We find that BNs can assimilate important factors contributing to coastal change in response to sea level rise and can make quantitative, probabilistic predictions that can be applied to coastal management decisions. Copyright ?? 2011 by the American Geophysical Union.
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Fast rise times and the physical mechanism of deep earthquakes
NASA Technical Reports Server (NTRS)
Houston, H.; Williams, Q.
1991-01-01
A systematic global survey of the rise times and stress drops of deep and intermediate earthquakes is reported. When the rise times are scaled to the seismic moment release of the events, their average is nearly twice as fast for events deeper than about 450 km as for shallower events.
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Population dynamics of Hawaiian seabird colonies vulnerable to sea-level rise.
Hatfield, Jeff S; Reynolds, Michelle H; Seavy, Nathaniel E; Krause, Crystal M
2012-08-01
Globally, seabirds are vulnerable to anthropogenic threats both at sea and on land. Seabirds typically nest colonially and show strong fidelity to natal colonies, and such colonies on low-lying islands may be threatened by sea-level rise. We used French Frigate Shoals, the largest atoll in the Hawaiian Archipelago, as a case study to explore the population dynamics of seabird colonies and the potential effects sea-level rise may have on these rookeries. We compiled historic observations, a 30-year time series of seabird population abundance, lidar-derived elevations, and aerial imagery of all the islands of French Frigate Shoals. To estimate the population dynamics of 8 species of breeding seabirds on Tern Island from 1980 to 2009, we used a Gompertz model with a Bayesian approach to infer population growth rates, density dependence, process variation, and observation error. All species increased in abundance, in a pattern that provided evidence of density dependence. Great Frigatebirds (Fregata minor), Masked Boobies (Sula dactylatra), Red-tailed Tropicbirds (Phaethon rubricauda), Spectacled Terns (Onychoprion lunatus), and White Terns (Gygis alba) are likely at carrying capacity. Density dependence may exacerbate the effects of sea-level rise on seabirds because populations near carrying capacity on an island will be more negatively affected than populations with room for growth. We projected 12% of French Frigate Shoals will be inundated if sea level rises 1 m and 28% if sea level rises 2 m. Spectacled Terns and shrub-nesting species are especially vulnerable to sea-level rise, but seawalls and habitat restoration may mitigate the effects of sea-level rise. Losses of seabird nesting habitat may be substantial in the Hawaiian Islands by 2100 if sea levels rise 2 m. Restoration of higher-elevation seabird colonies represent a more enduring conservation solution for Pacific seabirds. Conservation Biology ©2012 Society for Conservation Biology. No claim to original
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Preparing Norfolk Area Students for America's Second Highest Sea Level Rise
NASA Astrophysics Data System (ADS)
Dunbar, R. R.
2017-12-01
The nonprofit Elizabeth River Project located in Hampton Roads, Virginia was awarded a 3-year national NOAA Environmental Literacy award 2016-2019 to teach 21,000 K-12 youth how to help restore one of the most polluted rivers on the Chesapeake Bay and to help create a resilient community that is facing impacts from the rising seas and changing climate. Through a community collaboration, partners are also creating perhaps the nation's first Youth Resilience Strategy with a vision, goals, best practices and resources on engaging youth to help create resilient cities facing environmental and economic changes. During Year 1, 7,000 elementary students held field investigations aboard the floating classroom Learning Barge and at Paradise Creek Nature Park and helped restore wetland restoration sites. Students performed inquiry based investigations, learned stewardship actions to help create resilience and showed a 40% increase in knowledge. Year 1 best practices in teaching resilience include youth: getting out of the classroom, discovering how rain water travels, performing bioblitzes and water quality testing, engaging in hands-on GreenSTEM activities, using investigation tools, creating innovative solutions to retain and reuse rain water, creating art and voicing their opinions on creating a resilient community.Lessons learned include developing engaging inquiry questions based on creating a resilient community. These included: "What are the impact of rising tides?", "How can sea level rise affect river animals?", "How can we be safe and prepare for extreme weather and flooding as the sea level rises?", "How has the way people worked with the Elizabeth River changed?", "How could sea level rise affect the Elizabeth River's water quality?", "How hot might the air temperature get by 2050 and what can we do to keep it cooler?", "What does this park show us about sea level rise and other ways our climate is changing?", "How do trees help make our park and community
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ERIC Educational Resources Information Center
Mohazzabi, Pirooz
2010-01-01
When an object is immersed in a liquid and released, it may sink to the bottom or rise to the surface and float. If the object's density is greater than that of the liquid, it sinks. If the object's density is less than the density of the liquid, it floats. In the special case when the object's density matches the density of the liquid, it will…
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Rumination syndrome: when the lower oesophageal sphincter rises.
Gourcerol, Guillaume; Dechelotte, Pierre; Ducrotte, Philippe; Leroi, Anne Marie
2011-07-01
Rumination syndrome is an uncommon condition characterised by the self-induced regurgitation from the stomach to the mouth of recently ingested meal that is chewed and reswallowed. Rumination is caused by a voluntary rise in intra-abdominal and intra-gastric pressure leading to the reflux of the gastric content into the oesophagus. However, the precise mechanisms preventing reflux at the gastro-oesophageal junction during the rise in intra-gastric pressure remains unknown. In 5 patients, rumination episodes were monitored using combined multiple intra-luminal impedance monitoring, high resolution manometry, and video-fluoroscopic recording. We showed that the gastro-oesophageal junction moved from the abdominal cavity into the thorax creating a "pseudo-hernia". This occurred at a range of 1.4 ± 0.3 s before the rise in intra-oesophageal pressure and the gastro-oesophageal reflux. This displacement of the gastro-oesophageal junction into thorax, rather than a lower oesophageal sphincter opening, explains the mechanism of voluntary regurgitations occurring during rumination syndrome. Copyright © 2011 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.
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Bermuda and Appalachian-Labrador rises: Common non-hotspot processes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vogt, P.R.
1991-01-01
Other than the Corner Rise-New England seamounts and associated White Mountains, most postbreakup intraplate igneous activity and topographic uplift in the western North Atlantic and eastern North America do not readily conform to simple hotspot models. For examples, the Bermuda Rise trends normal to its predicted hotspot trace. On continental crust, Cretaceous-Eocene igneous activity is scattered along a northeast-trending belt {approximately}500-1,000 km west of and paralleling the continent-ocean boundary. Corresponding activity in the western Atlantic generated seamounts preferentially clustered in a belt {approximately}1,000 km east of the boundary. The Eocene volcanism on Bermuda is paired with coeval magmatism of themore » Shenandoah igneous province, and both magmatic belts are associated with northeast-trending topographic bulges - the Appalachian-Labrador Rise to the west and the Bermuda Rise (Eocene ) to the east. The above observations suggest the existence of paired asthenosphere upwelling, paralleling and controlled by the deep thermal contrast across the northeast-trending continental margin. Such convection geometry, apparently fixed to the North American plate rather than to hotspots, is consistent with recent convection models by B. Hager. The additional importance of plate-kinematic reorganizations (causing midplate stress enhancement) is suggested by episodic igneous activity ca. 90-100 Ma and 40-45 Ma.« less
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Seismic performance of low-rise wood buildings
Lawrence A. Soltis; Robert H. Falk
1992-01-01
This article updates a previous literature review paper on the performance of woodframe buildings during earthquakes and summarizes recent research related to understanding seismic behavior of low-rise wood buildings.
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Pancreatic rupture in four cats with high-rise syndrome.
Liehmann, Lea M; Dörner, Judith; Hittmair, Katharina M; Schwendenwein, Ilse; Reifinger, Martin; Dupré, Gilles
2012-02-01
Pancreatic trauma and rupture are rare after feline high-rise syndrome; however, should it happen, pancreatic enzymes will leak into the abdominal cavity and may cause pancreatic autodigestion and fatty tissue saponification. If not diagnosed and treated, it can ultimately lead to multiorgan failure and death. In this case series, 700 records of high-rise syndrome cats that presented between April 2001 and May 2006 were analysed, and four cats with pancreatic rupture were identified. Clinical signs, diagnosis using ultrasonography and lipase activity in blood and abdominal effusion, and treatment modalities are reported. Three cats underwent surgical abdominal exploration, one cat was euthanased. Rupture of the left pancreatic limb was confirmed in all cases. Two of the operated cats survived to date. High-rise syndrome can lead to abdominal trauma, including pancreatic rupture. A prompt diagnosis and surgical treatment should be considered.
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How To Attack Rising Energy Costs.
ERIC Educational Resources Information Center
Fickes, Michael
2001-01-01
Presents manufacturer and engineer suggestions on how schools can solve their rising energy costs in the face of more demanding classroom needs placing greater demands of Heating and air conditioning ventilation systems. The use of CO2 sensors, boiler technology and two-pipe systems are explored. (GR)
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Wang, Nan; Allali, Gilles; Kesavadas, Chandrasekharan; Noone, Mohan L; Pradeep, Vayyattu G; Blumen, Helena M; Verghese, Joe
2016-01-01
The contribution of cerebral small vessel disease to cognitive decline, especially in non-Caucasian populations, is not well established. We examined the relationship between cerebral small vessel disease and motoric cognitive risk syndrome (MCR), a recently described pre-dementia syndrome, in Indian seniors. 139 participants (mean age 66.6 ± 5.4 y, 33.1% female) participating in the Kerala-Einstein study in Southern India were examined in a cross-sectional study. The presence of cerebral small vessel disease (lacunar infarcts and cerebral microbleeds (CMB)) and white matter hyperintensities on MRI was ascertained by raters blinded to clinical information. MCR was defined by the presence of cognitive complaints and slow gait in older adults without dementia or mobility disability. Thirty-eight (27.3%) participants met MCR criteria. The overall prevalence of lacunar infarcts and CMB was 49.6% and 9.4% , respectively. Lacunar infarcts in the frontal lobe, but no other brain regions, were associated with MCR even after adjusting for vascular risk factors and presence of white matter hyperintensities (adjusted Odds Ratio (aOR): 4.67, 95% CI: 1.69-12.94). Frontal lacunar infarcts were associated with slow gait (aOR: 3.98, 95% CI: 1.46-10.79) and poor performance on memory test (β: -1.24, 95% CI: -2.42 to -0.05), but not with cognitive complaints or non-memory tests. No association of CMB was found with MCR, individual MCR criterion or cognitive tests. Frontal lacunar infarcts are associated with MCR in Indian seniors, perhaps, by contributing to slow gait and poor memory function.
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Analysis of global impacts of sea-level rise: a case study of flooding
NASA Astrophysics Data System (ADS)
Nicholls, Robert J.
Analysis of the response to climate change and sea-level rise requires a link from climate change science to the resulting impacts and their policy implications. This paper explores the impacts of sea-level rise, particularly increased coastal flooding due to storm surges. In particular, it asks the simple question “how much will projected global sea-level rise exacerbate coastal flood problems, if ignored?” This is an important question to the intergovernmental process considering climate change. Further many countries presently ignore sea-level rise in long-term coastal planning, even though global sea levels are presently slowly rising. Using the model of Nicholls et al. [Global Environmental Change 9 (1999) S69], the analysis considers the flood impacts of sea-level rise on an “IS92a world” based on a consistent set of scenarios of global-mean sea-level rise, subsidence (where appropriate), coastal population change (usually increase), and flood defence standards (derived from GDP/capita). Two of the protection scenarios consider the possible upgrade of flood defences, but no allowance for global-mean sea-level rise is allowed to ensure consistency with the question being investigated. This model has been validated against national- and regional-scale assessments indicating that the relative results are reasonable, and the absolute results are of the right order of magnitude. The model estimates that 10 million people experienced flooding annually in 1990. It also predicts that the incidence of flooding will change without sea-level rise due to changes to the other three factors. Taking the full range of scenarios considered by 2100 the number of people flooded could be from 0.4 to 39 million/year. All the sea-level rise scenarios would cause an increase in flooding during the 21st century if measures to adapt to sea-level rise are not taken. However, there are significant uncertainties and the number of people who are estimated to experience flooding
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Rise time measurement for ultrafast X-ray pulses
Celliers, Peter M [Berkeley, CA; Weber, Franz A [Oakland, CA; Moon, Stephen J [Tracy, CA
2005-04-05
A pump-probe scheme measures the rise time of ultrafast x-ray pulses. Conventional high speed x-ray diagnostics (x-ray streak cameras, PIN diodes, diamond PCD devices) do not provide sufficient time resolution to resolve rise times of x-ray pulses on the order of 50 fs or less as they are being produced by modern fast x-ray sources. Here, we are describing a pump-probe technique that can be employed to measure events where detector resolution is insufficient to resolve the event. The scheme utilizes a diamond plate as an x-ray transducer and a p-polarized probe beam.
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Rise Time Measurement for Ultrafast X-Ray Pulses
Celliers, Peter M.; Weber, Franz A.; Moon, Stephen J.
2005-04-05
A pump-probe scheme measures the rise time of ultrafast x-ray pulses. Conventional high speed x-ray diagnostics (x-ray streak cameras, PIN diodes, diamond PCD devices) do not provide sufficient time resolution to resolve rise times of x-ray pulses on the order of 50 fs or less as they are being produced by modern fast x-ray sources. Here, we are describing a pump-probe technique that can be employed to measure events where detector resolution is insufficient to resolve the event. The scheme utilizes a diamond plate as an x-ray transducer and a p-polarized probe beam.
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46 CFR 111.20-5 - Temperature rise.
Code of Federal Regulations, 2012 CFR
2012-10-01
... REQUIREMENTS Transformer Construction, Installation, and Protection § 111.20-5 Temperature rise. (a) The... than 40 degrees C, the transformer must be derated so that the total temperature stated in this section...
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46 CFR 111.20-5 - Temperature rise.
Code of Federal Regulations, 2014 CFR
2014-10-01
... REQUIREMENTS Transformer Construction, Installation, and Protection § 111.20-5 Temperature rise. (a) The... than 40 degrees C, the transformer must be derated so that the total temperature stated in this section...
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46 CFR 111.20-5 - Temperature rise.
Code of Federal Regulations, 2013 CFR
2013-10-01
... REQUIREMENTS Transformer Construction, Installation, and Protection § 111.20-5 Temperature rise. (a) The... than 40 degrees C, the transformer must be derated so that the total temperature stated in this section...
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46 CFR 111.20-5 - Temperature rise.
Code of Federal Regulations, 2010 CFR
2010-10-01
... REQUIREMENTS Transformer Construction, Installation, and Protection § 111.20-5 Temperature rise. (a) The... than 40 degrees C, the transformer must be derated so that the total temperature stated in this section...
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46 CFR 111.20-5 - Temperature rise.
Code of Federal Regulations, 2011 CFR
2011-10-01
... REQUIREMENTS Transformer Construction, Installation, and Protection § 111.20-5 Temperature rise. (a) The... than 40 degrees C, the transformer must be derated so that the total temperature stated in this section...
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Fiber Reinforced Concrete (FRC) for High Rise Construction: Case Studies
NASA Astrophysics Data System (ADS)
Gharehbaghi, Koorosh; Chenery, Rhea
2017-12-01
Due to its material element, Fiber Reinforced Concrete (FRC) could be stronger than traditional Concrete. This is due to FRC internal material compounds and elements. Furthermore, FRC can also significantly improve flexural strength when compared to traditional Concrete. This improvement in flexural strength can be varied depending on the actual fibers used. Although not new, FRC is gradually gaining popularity in the construction industry, in particular for high rise structures. This is due to its flexural strength, especially for high seismic zones, as it will provide a better solution then reinforced Concrete. The main aim of this paper is to investigate the structural importance of FRC for the high rise construction. Although there has been numerous studies and literature in justifying the FRC for general construction; this paper will consider its use specifically for high rise construction. Moreover, this paper will closely investigate eight case studies from Australian and United States as a part of the FRC validation for high rise construction. In doing so, this paper will examine their Structural Health Monitoring (SHM) to determine their overall structural performance.
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Calculation of Temperature Rise in Calorimetry.
ERIC Educational Resources Information Center
Canagaratna, Sebastian G.; Witt, Jerry
1988-01-01
Gives a simple but fuller account of the basis for accurately calculating temperature rise in calorimetry. Points out some misconceptions regarding these calculations. Describes two basic methods, the extrapolation to zero time and the equal area method. Discusses the theoretical basis of each and their underlying assumptions. (CW)
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Processes contributing to resilience of coastal wetlands to sea-level rise
Stagg, Camille L.; Krauss, Ken W.; Cahoon, Donald R.; Cormier, Nicole; Conner, William H.; Swarzenski, Christopher M.
2016-01-01
The objectives of this study were to identify processes that contribute to resilience of coastal wetlands subject to rising sea levels and to determine whether the relative contribution of these processes varies across different wetland community types. We assessed the resilience of wetlands to sea-level rise along a transitional gradient from tidal freshwater forested wetland (TFFW) to marsh by measuring processes controlling wetland elevation. We found that, over 5 years of measurement, TFFWs were resilient, although some marginally, and oligohaline marshes exhibited robust resilience to sea-level rise. We identified fundamental differences in how resilience is maintained across wetland community types, which have important implications for management activities that aim to restore or conserve resilient systems. We showed that the relative importance of surface and subsurface processes in controlling wetland surface elevation change differed between TFFWs and oligohaline marshes. The marshes had significantly higher rates of surface accretion than the TFFWs, and in the marshes, surface accretion was the primary contributor to elevation change. In contrast, elevation change in TFFWs was more heavily influenced by subsurface processes, such as root zone expansion or compaction, which played an important role in determining resilience of TFFWs to rising sea level. When root zone contributions were removed statistically from comparisons between relative sea-level rise and surface elevation change, sites that previously had elevation rate deficits showed a surplus. Therefore, assessments of wetland resilience that do not include subsurface processes will likely misjudge vulnerability to sea-level rise.
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... The Pacific Islands: Fiji , Papua New Guinea , Samoa , Solomon Islands , Tonga South America: Argentina , Bolivia , Brazil , Colombia , ... travel plans. Area Date of interruption American Samoa 4/13/2017 The Bahamas 2/2/2018 Cayman ...
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... Verde Cayman Islands Central African Republic Chad Chile China Christmas Island Cocos (Keeling) Islands Colombia Comoros Congo ... Sweden Switzerland Syrian Arab Republic Taiwan, Republic of China Tajikistan Tanzania, United Republic of Thailand Togo Tokelau ...
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Optimizing smoke and plume rise modeling approaches at local scales
Derek V. Mallia; Adam K. Kochanski; Shawn P. Urbanski; John C. Lin
2018-01-01
Heating from wildfires adds buoyancy to the overlying air, often producing plumes that vertically distribute fire emissions throughout the atmospheric column over the fire. The height of the rising wildfire plume is a complex function of the size of the wildfire, fire heat flux, plume geometry, and atmospheric conditions, which can make simulating plume rises difficult...
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Validation of smoke plume rise models using ground based lidar
Cyle E. Wold; Shawn Urbanski; Vladimir Kovalev; Alexander Petkov; Wei Min Hao
2010-01-01
Biomass fires can significantly degrade regional air quality. Plume rise height is one of the critical factors determining the impact of fire emissions on air quality. Plume rise models are used to prescribe the vertical distribution of fire emissions which are critical input for smoke dispersion and air quality models. The poor state of model evaluation is due in...
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Rise-Time of FRET-Acceptor Fluorescence Tracks Protein Folding
Lindhoud, Simon; Westphal, Adrie H.; van Mierlo, Carlo P. M.; Visser, Antonie J. W. G.; Borst, Jan Willem
2014-01-01
Uniform labeling of proteins with fluorescent donor and acceptor dyes with an equimolar ratio is paramount for accurate determination of Förster resonance energy transfer (FRET) efficiencies. In practice, however, the labeled protein population contains donor-labeled molecules that have no corresponding acceptor. These FRET-inactive donors contaminate the donor fluorescence signal, which leads to underestimation of FRET efficiencies in conventional fluorescence intensity and lifetime-based FRET experiments. Such contamination is avoided if FRET efficiencies are extracted from the rise time of acceptor fluorescence upon donor excitation. The reciprocal value of the rise time of acceptor fluorescence is equal to the decay rate of the FRET-active donor fluorescence. Here, we have determined rise times of sensitized acceptor fluorescence to study the folding of double-labeled apoflavodoxin molecules and show that this approach tracks the characteristics of apoflavodoxinʼs complex folding pathway. PMID:25535076
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Fertility postponement is largely due to rising educational enrolment
Bhrolcháin, Máire Ní; Beaujouan, Éva
2012-01-01
The rise in educational enrolment is often cited as a possible cause of the trend to later childbearing in developed societies but direct evidence of its contribution to the aggregate change in fertility tempo is scarce. We show that rising enrolment, resulting in later ages at the end of education, accounts for a substantial part of the upward shift in the mean age at first birth in the 1980s and 1990s in Britain and in France. The postponement of first birth over that period has two components: a longer average period of enrolment and a post-enrolment component that is also related to educational level. The relationship between rising educational participation and the move to later fertility timing is almost certainly causal. Our findings therefore suggest that fertility tempo change is rooted in macro-economic and structural forces rather than in the cultural domain. PMID:22889178
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The problems and perspectives for the introduction of high-rise construction in Russian cities
NASA Astrophysics Data System (ADS)
Pershina, Anna; Radzhabov, Mehman; Dormidontova, Tatyana
2018-03-01
The propose of academic affairs is discovery the principal areas of concern high-rise construction in Russia. Examples of modern Russian and foreign high-rise construction are considered in the work. The most important problems and their solutions for Russia are identified on their basis. The everyone area of concern is considered separately. Ecology problems and influence of high-rise construction for the healthy and psychological effect of people are considered special. High-rise constructions influence negative and positive for urban environment in Moscow and Samara cities. The experience lack, defects in requirements document, which don't include all high-rise constructions specific, system problem of construction and often non-availability of proper control at the existing requirements document result for complexity of designing, construction and operation. At this moment, high-rise constructions temp is increasing in Moscow. Feasibility of high-rise buildings come up in regions of Russia. The reasons include high material inputs, irregularities of requirements network and utility lines and maintenance problems. The researching follow up of conclusions and recommendations for high-rise constructions development in Russia. The reasons of high-rise buildings are urbanization of people and necessary of concentration labor supply. The important tasks for organization are creating compact urban environment, decrease urban area for development, using an innovative technology for construction and properly maintenance. The balance between the preference of high-rise construction, inputs for construction and influence for ecology are resolve for this task.
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Dynamic facade module prototype development for solar radiation prevention in high rise building
NASA Astrophysics Data System (ADS)
Sega Sufia Purnama, Muhammad; Sutanto, Dalhar
2018-03-01
Solar radiation is an aspect that high rise building must avoid. The problem is, if high rise building facade can’t overcome, the solar thermal will come in the building, and its affects on the increasing of room temperature above comfort range. A type of additional facade element that could solve solar thermal in high rise building is adding a sun shading. A dynamic facade is a shade plane in high rise building that can moved or changed on outside condition such as solar movement and intensity. This research will discuss the dynamic facade module prototype development in high rise building in Jakarta. This research will be finish through some step. (1) Static shading shadow simulation. (2) Dynamic facade concept design development. (3) Dynamic shading shadow simulation. (4) Making of dynamic facade module prototype. (5) Field test for the dynamic facade module prototype. The dynamic facade in Jakarta case will be effective to solve solar transmission in high rise building rather than static facade.
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The Rise of School-Supporting Nonprofits
ERIC Educational Resources Information Center
Nelson, Ashlyn Aiko; Gazley, Beth
2014-01-01
This paper examines voluntary contributions to public education via charitable school foundations, booster clubs, parent teacher associations, and parent teacher organizations. We use panel data on school-supporting charities with national coverage from 1995 to 2010, which we geocode and match to school districts. We document the meteoric rise of…
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Capillary rise and swelling in cellulose sponges
NASA Astrophysics Data System (ADS)
Ha, Jonghyun; Kim, Jungchul; Kim, Ho-Young
2015-11-01
A cellulose sponge, which is a mundane example of a porous hydrophilic structure, can absorb and hold a significant amount of liquid. We present the results of experimental and theoretical investigation of the dynamics of the capillary imbibition of various aqueous solutions in the sponge that swells at the same time. We find that the rate of water rise against the resistance caused by gravitational and viscous effects deviates from Washburn's rule beyond a certain threshold height. We rationalize the novel power law of the rise height versus time by combining Darcy's law with hygroscopic swelling equation and also predict the threshold height. The scaling law constructed through this work agrees well with the experimental results, shedding light on the physics of capillary flow in deforming porous media.
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Hurricanes, sea level rise, and coastal change
Sallenger,, Asbury H.; Wang, Ping; Rosati, Julie D.; Roberts, Tiffany M.
2011-01-01
Sixteen hurricanes have made landfall along the U.S. east and Gulf coasts over the past decade. For most of these storms, the USGS with our partners in NASA and the U.S. Army Corps of Engineers have flown before and after lidar missions to detect changes in beaches and dunes. The most dramatic changes occurred when the coasts were completely submerged in an inundation regime. Where this occurred locally, a new breach was cut, like during Hurricane Isabel in North Carolina. Where surge inundated an entire island, the sand was stripped off leaving marshy outcrops behind, like during Hurricane Katrina in Louisiana. Sea level rise together with sand starvation and repeated hurricane impacts could increase the probabilities of inundation and degrade coasts more than sea level rise alone.
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[Pigment dispersion and Artisan implants: crystalline lens rise as a safety criterion].
Baikoff, G; Bourgeon, G; Jodai, H Jitsuo; Fontaine, A; Vieira Lellis, F; Trinquet, L
2005-06-01
To validate the theoretical notion of a crystalline lens rise as a safety criterion for ARTISAN implants in order to prevent the development of pigment dispersion in the implanted eye. Crystalline lens rise is defined by the distance between the crystalline lens's anterior pole and the horizontal plane joining the opposite iridocorneal recesses. We analyzed the biometric measurements of 87 eyes with an Artisan implant. A comparative analysis of the crystalline lens rise was carried out on the nine eyes having developed pigment dispersion and 78 eyes with no problems. Among the modern anterior segment imaging devices (Artemis, Scheimpflug photography, optical coherence tomography, radiology exploration, magnetic resonance imaging, TDM), an anterior chamber optical coherence tomography (AC-OCT) prototype was used. This working hypothesis was confirmed by this study: the crystalline lens rise must be considered as a new safety criterion for implanting Artisan phakic lenses. Indeed, the higher the crystalline lens's rise, the greater the risk of developing pigment dispersion in the pupil area. This complication is more frequent in hyperopes than in myopes. We can consider that there is little or no risk of pigment dispersion if the rise is below 600 microm; however, at 600 microm or greater, there is a 67% rate of pupillary pigment dispersion. In certain cases, when the implant was loosely fixed, there was no traction on the iris root. This is a complication that can be avoided or delayed. The crystalline lens rise must be part of new safety criteria to be taken into consideration when inserting an Artisan implant. This notion must also be applied to other types of phakic implants. The distance remaining between the crystalline lens rise and a 600-micromm theoretical safety level allows one to calculate a safety time interval.
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NASA Astrophysics Data System (ADS)
Sterner, E.; Johansson, D. J.
2013-12-01
Climate change depends on the increase of several different atmospheric pollutants. While long term global warming will be determined mainly by carbon dioxide, warming in the next few decades will depend to a large extent on short lived climate pollutants (SLCP). Reducing emissions of SLCPs could contribute to lower the global mean surface temperature by 0.5 °C already by 2050 (Shindell et al. 2012). Furthermore, the warming effect of one of the most potent SLCPs, black carbon (BC), may have been underestimated in the past. Bond et al. (2013) presents a new best estimate of the total BC radiative forcing (RF) of 1.1 W/m2 (90 % uncertainty bounds of 0.17 to 2.1 W/m2) since the beginning of the industrial era. BC is however never emitted alone and cooling aerosols from the same sources offset a majority of this RF. In the wake of calls for mitigation of SLCPs it is important to study other aspects of the climate effect of SLCPs. One key impact of climate change is sea-level rise (SLR). In a recent study, the effect of SLCP mitigation scenarios on SLR is examined. Hu et al (2013) find a substantial effect on SLR from mitigating SLCPs sharply, reducing SLR by 22-42% by 2100. We choose a different approach focusing on emission pulses and analyse a metric based on sea level rise so as to further enlighten the SLR consequences of SLCPs. We want in particular to understand the time dynamics of SLR impacts caused by SLCPs compared to other greenhouse gases. The most commonly used physical based metrics are GWP and GTP. We propose and evaluate an additional metric: The global sea-level rise potential (GSP). The GSP is defined as the sea level rise after a time horizon caused by an emissions pulse of a forcer to the sea level rise after a time horizon caused by an emissions pulse of a CO2. GSP is evaluated and compared to GWP and GTP using a set of climate forcers chosen to cover the whole scale of atmospheric perturbation life times (BC, CH4, N2O, CO2 and SF6). The study
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Disability Rises Gradually for a Cohort of Older Americans
Brown, Dustin C.; Zajacova, Anna
2017-01-01
Objectives: We study changes in average disability over nearly two decades for a large epidemiological cohort of older Americans. As some people exit by mortality, do average disability levels for the living cohort rise rapidly, rise gradually, stay steady, or decline? Method: Data are from the Study of Asset and Health Dynamics Among the Oldest Old (AHEAD) cohort for 1993–2010. Cohort members are aged 70+ in 1993 (mean = 77.5 years), and the survivors are aged 87+ in 2010 (mean = 90.2 years). Personal care disability (activities of daily living), household management disability (instrumental activities of daily living), and physical limitations are studied. We study average disability for the living cohort over time and the disability histories for decedent and survivor groups. Results: Average disability rises gradually over time for the living cohort. Earlier decedent groups have higher average disability than later ones. Near death, disability rises sharply for all decedent groups. Longer surviving groups have less average disability, and slower disability increases, than shorter surviving groups. All results are repeated for younger cohort members (baseline age = 70–79 years), older ones (baseline age = 80+ years), women, and men. Discussion: As a cohort ages, average disability among living members increases gradually, signaling behavioral, psychological, and biological fitness in very old persons. PMID:26968638
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Methodology for determining the investment attractiveness of construction of high-rise buildings
NASA Astrophysics Data System (ADS)
Nezhnikova, Ekaterina; Kashirin, Valentin; Davydova, Yana; Kazakova, Svetlana
2018-03-01
The article presents the analysis of the existing methods for assessing the investment attractiveness of high-rise construction. The authors determined and justified the primary choice of objects and territories that are the most attractive for the development of high-rise construction. A system of risk indicators has been developed that allow making a quantitative adjustment for a particular project in the evaluation of the efficiency of investment projects. The study is aimed at developing basic methodological concepts for a comparative evaluation of the prospects of construction of high-rise facilities that allow to take into consideration the features of investment in construction and to enable quantitative evaluation of the investment effectiveness in high-rise construction.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Nayak, Dipti D.; Mahanta, Nilkamal; Mitchell, Douglas A.
Methyl-coenzyme M reductase (MCR), found in strictly anaerobic methanogenic and methanotrophic archaea, catalyzes the reversible production and consumption of the potent greenhouse gas methane. The α subunit of MCR (McrA) contains several unusual post-translational modifications, including a rare thioamidation of glycine. Based on the presumed function of homologous genes involved in the biosynthesis of thioviridamide, a thioamide-containing natural product, we hypothesized that the archaeal tfuA and ycaO genes would be responsible for post-translational installation of thioglycine into McrA. Mass spectrometric characterization of McrA from the methanogenic archaeon Methanosarcina acetivorans lacking tfuA and/or ycaO revealed the presence of glycine, rather thanmore » thioglycine, supporting this hypothesis. Phenotypic characterization of the ∆ycaO-tfuA mutant revealed a severe growth rate defect on substrates with low free energy yields and at elevated temperatures (39°C - 45°C). Our analyses support a role for thioglycine in stabilizing the protein secondary structure near the active site.« less
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Stojanoski, Vlatko; Sankaran, Banumathi; Prasad, B. V. Venkataram
Due to the paucity of novel antibiotics, colistin has become a last resort antibiotic for treating multidrug resistant bacteria. Colistin acts by binding the lipid A component of lipopolysaccharides and subsequently disrupting the bacterial membrane. The recently identified plasmid-encoded MCR-1 enzyme is the first transmissible colistin resistance determinant and is a cause for concern for the spread of this resistance trait. MCR-1 is a phosphoethanolamine transferase that catalyzes the addition of phosphoethanolamine to lipid A to decrease colistin affinity. The structure of the catalytic domain of MCR-1 at 1.32 Å reveals the active site is similar to that of relatedmore » phosphoethanolamine transferases. The putative nucleophile for catalysis, threonine 285, is phosphorylated in cMCR-1 and a zinc is present at a conserved site in addition to three zincs more peripherally located in the active site. As noted for catalytic domains of other phosphoethanolamine transferases, binding sites for the lipid A and phosphatidylethanolamine substrates are not apparent in the cMCR-1 structure, suggesting that they are present in the membrane domain.« less
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Nayak, Dipti D.; Mahanta, Nilkamal; Mitchell, Douglas A.; ...
2017-09-07
Methyl-coenzyme M reductase (MCR), found in strictly anaerobic methanogenic and methanotrophic archaea, catalyzes the reversible production and consumption of the potent greenhouse gas methane. The α subunit of MCR (McrA) contains several unusual post-translational modifications, including a rare thioamidation of glycine. Based on the presumed function of homologous genes involved in the biosynthesis of thioviridamide, a thioamide-containing natural product, we hypothesized that the archaeal tfuA and ycaO genes would be responsible for post-translational installation of thioglycine into McrA. Mass spectrometric characterization of McrA from the methanogenic archaeon Methanosarcina acetivorans lacking tfuA and/or ycaO revealed the presence of glycine, rather thanmore » thioglycine, supporting this hypothesis. Phenotypic characterization of the ∆ycaO-tfuA mutant revealed a severe growth rate defect on substrates with low free energy yields and at elevated temperatures (39°C - 45°C). Our analyses support a role for thioglycine in stabilizing the protein secondary structure near the active site.« less
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Characterization of a Methanogenic Community within an Algal Fed Anaerobic Digester
Ellis, Joshua T.; Tramp, Cody; Sims, Ronald C.; Miller, Charles D.
2012-01-01
The microbial diversity and metabolic potential of a methanogenic consortium residing in a 3785-liter anaerobic digester, fed with wastewater algae, was analyzed using 454 pyrosequencing technology. DNA was extracted from anaerobic sludge material and used in metagenomic analysis through PCR amplification of the methyl-coenzyme M reductase α subunit (mcrA) gene using primer sets ML, MCR, and ME. The majority of annotated mcrA sequences were assigned taxonomically to the genera Methanosaeta in the order Methanosarcinales. Methanogens from the genus Methanosaeta are obligate acetotrophs, suggesting this genus plays a dominant role in methane production from the analyzed fermentation sample. Numerous analyzed sequences within the algae fed anaerobic digester were unclassified and could not be assigned taxonomically. Relative amplicon frequencies were determined for each primer set to determine the utility of each in pyrosequencing. Primer sets ML and MCR performed better quantitatively (representing the large majority of analyzed sequences) than primer set ME. However, each of these primer sets was shown to provide a quantitatively unique community structure, and thus they are of equal importance in mcrA metagenomic analysis. PMID:23724331
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Caffeine poisoning and lactate rise: an overlooked toxic effect?
Schmidt, A; Karlson-Stiber, C
2008-08-01
Severe caffeine poisoning is rare but associated with a high mortality. The symptoms are mainly attributable to hyperadrenergic stimulation, are relatively well known and described in the literature. Transient rises in plasma lactate levels may occur but are, however, less well described. We present a case of serious caffeine poisoning with a concomitant rise in lactate treated with a non-selective beta-blocker and discuss briefly the symptomatology, the management of caffeine poisoning and the association between lactate and metabolic acidosis.
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Improvement of the cost-benefit analysis algorithm for high-rise construction projects
NASA Astrophysics Data System (ADS)
Gafurov, Andrey; Skotarenko, Oksana; Plotnikov, Vladimir
2018-03-01
The specific nature of high-rise investment projects entailing long-term construction, high risks, etc. implies a need to improve the standard algorithm of cost-benefit analysis. An improved algorithm is described in the article. For development of the improved algorithm of cost-benefit analysis for high-rise construction projects, the following methods were used: weighted average cost of capital, dynamic cost-benefit analysis of investment projects, risk mapping, scenario analysis, sensitivity analysis of critical ratios, etc. This comprehensive approach helped to adapt the original algorithm to feasibility objectives in high-rise construction. The authors put together the algorithm of cost-benefit analysis for high-rise construction projects on the basis of risk mapping and sensitivity analysis of critical ratios. The suggested project risk management algorithms greatly expand the standard algorithm of cost-benefit analysis in investment projects, namely: the "Project analysis scenario" flowchart, improving quality and reliability of forecasting reports in investment projects; the main stages of cash flow adjustment based on risk mapping for better cost-benefit project analysis provided the broad range of risks in high-rise construction; analysis of dynamic cost-benefit values considering project sensitivity to crucial variables, improving flexibility in implementation of high-rise projects.
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Subpicosecond luminescence rise time in magnesium codoped GAGG:Ce scintillator
NASA Astrophysics Data System (ADS)
Tamulaitis, G.; Vaitkevičius, A.; Nargelas, S.; Augulis, R.; Gulbinas, V.; Bohacek, P.; Nikl, M.; Borisevich, A.; Fedorov, A.; Korjik, M.; Auffray, E.
2017-10-01
The influence of co-doping of Gd3Al2GA3O12:Ce (GAGG:Ce) scintillator with magnesium on the rise time of luminescence response was studied in two GAGG:Ce crystals grown in nominally identical conditions except of Mg co-doping in one of them. Time-resolved photoluminescence spectroscopy and free carrier absorption techniques were exploited. It is evidenced that the Mg co-doping decreases the rise time down to sub-picosecond domain. Meanwhile, the light yield decreases by ∼20%. Thus, the feasibility of exploitation of the fast rise edge in luminescence response for ultrafast timing in scintillation detectors is demonstrated. The role of Mg impurities in facilitating the excitation transfer to radiative recombination centers is discussed.
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NASA Technical Reports Server (NTRS)
2007-01-01
New Horizons took this image of the icy moon Europa rising above Jupiter's cloud tops with its Long Range Reconnaissance Imager (LORRI) at 11:48 Universal Time on February 28, 2007, six hours after the spacecraft's closest approach to Jupiter. The picture was one of a handful of the Jupiter system that New Horizons took primarily for artistic, rather than scientific, value. This particular scene was suggested by space enthusiast Richard Hendricks of Austin, Texas, in response to an Internet request by New Horizons scientists for evocative, artistic imaging opportunities at Jupiter. The spacecraft was 2.3 million kilometers (1.4 million miles) from Jupiter and 3 million kilometers (1.8 million miles) from Europa when the picture was taken. Europa's diameter is 3,120 kilometers (1,939 miles). The image is centered on Europa coordinates 5 degrees south, 6 degrees west. In keeping with its artistic intent - and to provide a more dramatic perspective - the image has been rotated so south is at the top. -
MODELING THE RISE OF FIBRIL MAGNETIC FIELDS IN FULLY CONVECTIVE STARS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Weber, Maria A.; Browning, Matthew K., E-mail: mweber@astro.ex.ac.uk
Many fully convective stars exhibit a wide variety of surface magnetism, including starspots and chromospheric activity. The manner by which bundles of magnetic field traverse portions of the convection zone to emerge at the stellar surface is not especially well understood. In the solar context, some insight into this process has been gleaned by regarding the magnetism as consisting partly of idealized thin flux tubes (TFTs). Here we present the results of a large set of TFT simulations in a rotating spherical domain of convective flows representative of a 0.3 M {sub ⊙} main-sequence star. This is the first studymore » to investigate how individual flux tubes in such a star might rise under the combined influence of buoyancy, convection, and differential rotation. A time-dependent hydrodynamic convective flow field, taken from separate 3D simulations calculated with the anelastic equations, impacts the flux tube as it rises. Convective motions modulate the shape of the initially buoyant flux ring, promoting localized rising loops. Flux tubes in fully convective stars have a tendency to rise nearly parallel to the rotation axis. However, the presence of strong differential rotation allows some initially low-latitude flux tubes of moderate strength to develop rising loops that emerge in the near-equatorial region. Magnetic pumping suppresses the global rise of the flux tube most efficiently in the deeper interior and at lower latitudes. The results of these simulations aim to provide a link between dynamo-generated magnetic fields, fluid motions, and observations of starspots for fully convective stars.« less
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Propagation of solutes and pressure into aquifers following river stage rise
NASA Astrophysics Data System (ADS)
Welch, Chani; Cook, Peter G.; Harrington, Glenn A.; Robinson, Neville I.
2013-09-01
Water level rises associated with river flow events induce both pressure and solute movement into adjacent aquifers at vastly different rates. We present a simple analytical solution that relates the travel time and travel distance of solutes into an aquifer following river stage rise to aquifer properties. Combination with an existing solution for pressure propagation indicates that the ratio of solute to pressure travel times is proportional to the ratio of the volume of water stored in the aquifer before the river stage rise and the volume added by the stage rise and is independent of hydraulic conductivity. Two-dimensional numerical simulations of an aquifer slice perpendicular to a river demonstrate that the solutions are broadly applicable to variably saturated aquifers and partially penetrating rivers. The solutions remain applicable where river stage rise and fall occur, provided that regional hydraulic gradients are low and the duration of the river stage rise is less than pressure and solute travel times to the observation point in the aquifer. Consequently, the solutions provide new insight into the relationships between aquifer properties and distance and time of solute propagation and, in some cases, may be used to estimate system characteristics. Travel time metrics obtained for a flood event in the Cockburn River in eastern Australia using electrical conductivity measurements enabled estimates of aquifer properties and a lateral extent of river-aquifer mixing of 25 m. A detailed time series of any soluble tracer with distinctly different concentrations in river water and groundwater may be used.
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IT Requirements Integration in High-Rise Construction Design Projects
NASA Astrophysics Data System (ADS)
Levina, Anastasia; Ilin, Igor; Esedulaev, Rustam
2018-03-01
The paper discusses the growing role of IT support for the operation of modern high-rise buildings, due to the complexity of managing engineering systems of buildings and the requirements of consumers for the IT infrastructure. The existing regulatory framework for the development of design documentation for construction, including high-rise buildings, is analyzed, and the lack of coherence in the development of this documentation with the requirements for the creation of an automated management system and the corresponding IT infrastructure is stated. The lack of integration between these areas is the cause of delays and inefficiencies both at the design stage and at the stage of putting the building into operation. The paper proposes an approach to coordinate the requirements of the IT infrastructure of high-rise buildings and design documentation for construction. The solution to this problem is possible within the framework of the enterprise architecture concept by coordinating the requirements of the IT and technological layers at the design stage of the construction.
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The vulnerability of Indo-Pacific mangrove forests to sea-level rise
Lovelock, Catherine E.; Cahoon, Donald R.; Friess, Daniel A.; Guntenspergen, Glenn R.; Krauss, Ken W.; Reef, Ruth; Rogers, Kerrylee; Saunders, Megan L.; Sidik, Frida; Swales, Andrew; Saintilan, Neil; Thuyen, Le Xuan; Triet, Tran
2015-01-01
Sea-level rise can threaten the long-term sustainability of coastal communities and valuable ecosystems such as coral reefs, salt marshes and mangroves. Mangrove forests have the capacity to keep pace with sea-level rise and to avoid inundation through vertical accretion of sediments, which allows them to maintain wetland soil elevations suitable for plant growth. The Indo-Pacific region holds most of the world’s mangrove forests, but sediment delivery in this region is declining, owing to anthropogenic activities such as damming of rivers. This decline is of particular concern because the Indo-Pacific region is expected to have variable, but high, rates of future sea-level rise. Here we analyse recent trends in mangrove surface elevation changes across the Indo-Pacific region using data from a network of surface elevation table instruments. We find that sediment availability can enable mangrove forests to maintain rates of soil-surface elevation gain that match or exceed that of sea-level rise, but for 69 per cent of our study sites the current rate of sea-level rise exceeded the soil surface elevation gain. We also present a model based on our field data, which suggests that mangrove forests at sites with low tidal range and low sediment supply could be submerged as early as 2070.
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The vulnerability of Indo-Pacific mangrove forests to sea-level rise.
Lovelock, Catherine E; Cahoon, Donald R; Friess, Daniel A; Guntenspergen, Glenn R; Krauss, Ken W; Reef, Ruth; Rogers, Kerrylee; Saunders, Megan L; Sidik, Frida; Swales, Andrew; Saintilan, Neil; Thuyen, Le Xuan; Triet, Tran
2015-10-22
Sea-level rise can threaten the long-term sustainability of coastal communities and valuable ecosystems such as coral reefs, salt marshes and mangroves. Mangrove forests have the capacity to keep pace with sea-level rise and to avoid inundation through vertical accretion of sediments, which allows them to maintain wetland soil elevations suitable for plant growth. The Indo-Pacific region holds most of the world's mangrove forests, but sediment delivery in this region is declining, owing to anthropogenic activities such as damming of rivers. This decline is of particular concern because the Indo-Pacific region is expected to have variable, but high, rates of future sea-level rise. Here we analyse recent trends in mangrove surface elevation changes across the Indo-Pacific region using data from a network of surface elevation table instruments. We find that sediment availability can enable mangrove forests to maintain rates of soil-surface elevation gain that match or exceed that of sea-level rise, but for 69 per cent of our study sites the current rate of sea-level rise exceeded the soil surface elevation gain. We also present a model based on our field data, which suggests that mangrove forests at sites with low tidal range and low sediment supply could be submerged as early as 2070.
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The rise-time of Type II supernovae
NASA Astrophysics Data System (ADS)
González-Gaitán, S.; Tominaga, N.; Molina, J.; Galbany, L.; Bufano, F.; Anderson, J. P.; Gutierrez, C.; Förster, F.; Pignata, G.; Bersten, M.; Howell, D. A.; Sullivan, M.; Carlberg, R.; de Jaeger, T.; Hamuy, M.; Baklanov, P. V.; Blinnikov, S. I.
2015-08-01
We investigate the early-time light curves of a large sample of 223 Type II supernovae (SNe II) from the Sloan Digital Sky Survey and the Supernova Legacy Survey. Having a cadence of a few days and sufficient non-detections prior to explosion, we constrain rise-times, i.e. the durations from estimated first to maximum light, as a function of effective wavelength. At rest-frame g' band (λeff = 4722 Å), we find a distribution of fast rise-times with median of (7.5 ± 0.3) d. Comparing these durations with analytical shock models of Rabinak & Waxman and Nakar & Sari, and hydrodynamical models of Tominaga et al., which are mostly sensitive to progenitor radius at these epochs, we find a median characteristic radius of less than 400 solar radii. The inferred radii are on average much smaller than the radii obtained for observed red supergiants (RSG). Investigating the post-maximum slopes as a function of effective wavelength in the light of theoretical models, we find that massive hydrogen envelopes are still needed to explain the plateaus of SNe II. We therefore argue that the SN II rise-times we observe are either (a) the shock cooling resulting from the core collapse of RSG with small and dense envelopes, or (b) the delayed and prolonged shock breakout of the collapse of an RSG with an extended atmosphere or embedded within pre-SN circumstellar material.
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Modelling of energy consumption at construction of high-rise buildings
NASA Astrophysics Data System (ADS)
Korol, Elena; Korol, Oleg
2018-03-01
High-rise building structures in the course of its erection suppose primary use of methods provided for erection, concrete and external finishing works. Erection works do not differ significantly from usual ones: traditional equipment, accessories and techniques are used which are based on erection of structures in project position using a crane. Structures to be assembled in building frame include steel columns and beams, wall panels, form elements of columns, walls and floor structures. We can note heightened attention to operational control for quality of erection, but it is attributable to all works in the course of high-rise construction. During high-rise erection by means of cast in-situ reinforced concrete all formworks to be used do not have any special differences except systems specially designed for high-rise erection using sliding formwork or vertical traveling forms. In these systems special attention is paid to safety of elevated works. Working methods of placement and curing of concrete and structures as a whole remain traditional - the requirements for controlling such operations become toughened. The most evident differences in high-rise erection with regard to equipment, machinery and accessories used are in means provided for load transportation and safety of works at heights. Particularity of internal finishing works which are also obligatory during construction of skyscrapers allows not considering them in as technological differences from usual construction as far as the «height» of its execution is limited by height of particular floor and determined by price and building class.
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Space-based Observational Constraints for 1-D Plume Rise Models
NASA Technical Reports Server (NTRS)
Martin, Maria Val; Kahn, Ralph A.; Logan, Jennifer A.; Paguam, Ronan; Wooster, Martin; Ichoku, Charles
2012-01-01
We use a space-based plume height climatology derived from observations made by the Multi-angle Imaging SpectroRadiometer (MISR) instrument aboard the NASA Terra satellite to evaluate the ability of a plume-rise model currently embedded in several atmospheric chemical transport models (CTMs) to produce accurate smoke injection heights. We initialize the plume-rise model with assimilated meteorological fields from the NASA Goddard Earth Observing System and estimated fuel moisture content at the location and time of the MISR measurements. Fire properties that drive the plume-rise model are difficult to estimate and we test the model with four estimates for active fire area and four for total heat flux, obtained using empirical data and Moderate Resolution Imaging Spectroradiometer (MODIS) re radiative power (FRP) thermal anomalies available for each MISR plume. We show that the model is not able to reproduce the plume heights observed by MISR over the range of conditions studied (maximum r2 obtained in all configurations is 0.3). The model also fails to determine which plumes are in the free troposphere (according to MISR), key information needed for atmospheric models to simulate properly smoke dispersion. We conclude that embedding a plume-rise model using currently available re constraints in large-scale atmospheric studies remains a difficult proposition. However, we demonstrate the degree to which the fire dynamical heat flux (related to active fire area and sensible heat flux), and atmospheric stability structure influence plume rise, although other factors less well constrained (e.g., entrainment) may also be significant. Using atmospheric stability conditions, MODIS FRP, and MISR plume heights, we offer some constraints on the main physical factors that drive smoke plume rise. We find that smoke plumes reaching high altitudes are characterized by higher FRP and weaker atmospheric stability conditions than those at low altitude, which tend to remain confined
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Ice2sea - the future glacial contribution to sea-level rise
NASA Astrophysics Data System (ADS)
Vaughan, D. G.; Ice2sea Consortium
2009-04-01
The melting of continental ice (glaciers, ice caps and ice sheets) is a substantial source of current sea-level rise, and one that is accelerating more rapidly than was predicted even a few years ago. Indeed, the most recent report from Intergovernmental Panel on Climate Change highlighted that the uncertainty in projections of future sea-level rise is dominated by uncertainty concerning continental ice, and that understanding of the key processes that will lead to loss of continental ice must be improved before reliable projections of sea-level rise can be produced. Such projections are urgently required for effective sea-defence management and coastal adaptation planning. Ice2sea is a consortium of European institutes and international partners seeking European funding to support an integrated scientific programme to improve understanding concerning the future glacial contribution to sea-level rise. This includes improving understanding of the processes that control, past, current and future sea-level rise, and generation of improved estimates of the contribution of glacial components to sea-level rise over the next 200 years. The programme will include targeted studies of key processes in mountain glacier systems and ice caps (e.g. Svalbard), and in ice sheets in both polar regions (Greenland and Antarctica) to improve understanding of how these systems will respond to future climate change. It will include fieldwork and remote sensing studies, and develop a suite of new, cross-validated glacier and ice-sheet model. Ice2sea will deliver these results in forms accessible to scientists, policy-makers and the general public, which will include clear presentations of the sources of uncertainty. Our aim is both, to provide improved projections of the glacial contribution to sea-level rise, and to leave a legacy of improved tools and techniques that will form the basis of ongoing refinements in sea-level projection. Ice2sea will provide exciting opportunities for many
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High-rise construction in historical cities through the example of Saint Petersburg
NASA Astrophysics Data System (ADS)
Granstrem, Maria; Zolotareva, Milena; Slavina, Tatyana
2018-03-01
The article sets forth results of the landscape visual analysis of the interaction of high-rise construction facilities with the environment of historical urban spaces. A toxic connection of high-rise construction facilities with the established urban landscape was analyzed and recorded. One of the latest stages of the reconstruction of historical cities, which penetrated many European countries at the end of the 20th century, also started in the beginning of the 21st century in Russia, where the reconstruction of historical facilities and territories became one of the leading trends of architectural activity. Therefore, problems of the interaction between the old city and new high-rise construction nearby historical centers are extremely relevant for Russian architects. Specific features of Russian high-rise construction within visual borders of historical cities, developed at the turn of the 20th-21st centuries, repeat past urban-planning mistakes spread in Europe in the second half of the 20th century. High-rise construction in close proximity to historical centers of cities violates an established scale and destroys a historical city silhouette.
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Temperature rise induced by some light emitting diode and quartz-tungsten-halogen curing units.
Asmussen, Erik; Peutzfeldt, Anne
2005-02-01
Because of the risk of thermal damage to the pulp, the temperature rise induced by light-curing units should not be too high. LED (light emitting diode) curing units have the main part of their irradiation in the blue range and have been reported to generate less heat than QTH (quartz-tungsten-halogen) curing units. This study had two aims: first, to measure the temperature rise induced by ten LED and three QTH curing units; and, second, to relate the measured temperature rise to the power density of the curing units. The light-induced temperature rise was measured by means of a thermocouple embedded in a small cylinder of resin composite. The power density was measured by using a dental radiometer. For LED units, the temperature rise increased with increasing power density, in a statistically significant manner. Two of the three QTH curing units investigated resulted in a higher temperature rise than LED curing units of the same power density. Previous findings, that LED curing units induce less temperature rise than QTH units, does not hold true in general.
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Basement structures over Rio Grande Rise from gravity inversion
NASA Astrophysics Data System (ADS)
Constantino, Renata; Hackspacker, Peter Christian; Anderson de Souza, Iata; Sousa Lima Costa, Iago
2017-04-01
In this study, we show that from satellite-derived gravity field, bathymetry and sediment thicknesses, it is possible to give a 3-D model of the basement over oceanic areas, and for this purpose, we have chosen the Rio Grande Rise, in South Atlantic Ocean, to build a gravity-equivalent basement topography. The advantages of the method applied in this study are manifold: does not depend directly on reflection seismic data; can be applied quickly and with fewer costs for acquiring and interpreting the data; and as the main result, presents the physical surface below the sedimentary layer, which may be different from the acoustic basement. We evaluated the gravity effect of the sediments using the global sediment thickness model of NOAA, fitting a sediment compaction model to observed density values from Deep Sea Drilling Program (DSDP) reports. The Global Relief Model ETOPO1 and constraining data from seismic interpretation on crustal thickness are integrated in the gravity inversion procedure. The modeled Moho depth values vary between 6 to 27 km over the area, being thicker under the Rio Grande Rise and also in the direction of São Paulo Plateau. The inversion for the gravity-equivalent basement topography is applied for a gravity residual data, which is free from the gravity effect of sediments and from the gravity effect of the estimated Moho interface. A description of the basement depth over Rio Grande Rise area is unprecedented in the literature, however, our results could be compared to in situ data, provided by DSDP, and a small difference of only 9 m between our basement depth and leg 516 F was found. Our model shows a rift crossing the entire Rio Grande Rise deeper than previously presented in literature, with depths up to 5 km in the East Rio Grande Rise (ERGR) and deeper in the West Rio Grande Rise (WRGR), reaching 6.4 km. We find several short-wavelengths structures not present in the bathymetry data. Seamounts, guyots and fracture zones are much more
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Non-price competition in the regional high-rise construction market
NASA Astrophysics Data System (ADS)
Ganebnykh, Elena; Burtseva, Tatyana; Gurova, Ekaterina; Polyakova, Irina
2018-03-01
The article analyzes the market of high-rise residential construction in the city of Kirov (Russia). A minimal significance of price factors has been revealed in the process of the market analysis. This suggests that a lower price does not guarantee an increase in consumer demand. Thus, factors of non-price competition are of great importance in the market in question. The expert survey has identified the factors of non-price competition which influence consumer perceptions. A perceptual map has been constructed on the basis of the identified factors by means of the factor analysis to determine the positioning of each high-rise building relative to the consumer requirements. None of the high-rise residential buildings in the market in question meets the consumers' expectations of an "ideal facility".
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High-rise architecture in Ufa, Russia, based on crystallography canons
NASA Astrophysics Data System (ADS)
Narimanovich Sabitov, Ildar; Radikovna Kudasheva, Dilara; Yaroslavovich Vdovin, Denis
2018-03-01
The article considers fundamental steps of high-rise architecture forming stylistic tendencies, based on C. Willis and M. A. Korotich's studies. Crystallographic shaping as a direction is assigned on basis of classification by M. A. Korotich's. This direction is particularly examined and the main high-rise architecture forming aspects on basis of natural polycrystals forming principles are assigned. The article describes crystal forms transformation into an architectural composition, analyzes constructive systems within the framework of CTBUH (Council on Tall Buildings and Urban Habitat) classification, and picks out one of its types as the most optimal for using in buildings-crystals. The last stage of our research is the theoretical principles approbation into an experimental project of high-rise building in Ufa with the description of its contextual dislocation aspects.
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High-Rise Buildings versus Outdoor Thermal Environment in Chongqing
Lu, Jun; Chen, Jin-hua; Tang, Ying; Feng, Yuan; Wang, Jin-sha
2007-01-01
This paper gives a brief description of the over quick urbanization since Chongqing, one of the biggest cities in China, has been a municipality directly under the Central Government in 1997, excessive development and exceeding increase of high-rise buildings because of its special geographical position which finally leads to the worsening of the urban outdoor thermal environment. Then, this paper makes a bright balance to the field measurement and simulated results of the wind speed field, temperature field of one multifunctional high-rise building in Chongqing university located in the city center, and the contrasted results validate the correctness of CFD in the outdoor thermal environmental simulation, expose the disadvantages of high-rise buildings on the aspects of blocking the wind field, decreasing wind speed which results in accumulation of the air-conditioning heat revolving around and periscian region where sunshine can not rip into. Finally, in order to improve the urban outdoor thermal environment near the high-rise buildings especially for the angle of natural ventilation, this paper simulates the wind environment in different architectural compositions and architectural layouts by CFD, and the simulated results show that freestyle and tower buildings which can guarantee the wind speed and take the air-conditioning heat away are much suitable and reasonable for the special Chongqing geography. These conclusions can also be used as a reference in other mountain cities, especially for the one with a great number of populations. PMID:28903222
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Probabilistic reanalysis of twentieth-century sea-level rise.
Hay, Carling C; Morrow, Eric; Kopp, Robert E; Mitrovica, Jerry X
2015-01-22
Estimating and accounting for twentieth-century global mean sea level (GMSL) rise is critical to characterizing current and future human-induced sea-level change. Several previous analyses of tide gauge records--employing different methods to accommodate the spatial sparsity and temporal incompleteness of the data and to constrain the geometry of long-term sea-level change--have concluded that GMSL rose over the twentieth century at a mean rate of 1.6 to 1.9 millimetres per year. Efforts to account for this rate by summing estimates of individual contributions from glacier and ice-sheet mass loss, ocean thermal expansion, and changes in land water storage fall significantly short in the period before 1990. The failure to close the budget of GMSL during this period has led to suggestions that several contributions may have been systematically underestimated. However, the extent to which the limitations of tide gauge analyses have affected estimates of the GMSL rate of change is unclear. Here we revisit estimates of twentieth-century GMSL rise using probabilistic techniques and find a rate of GMSL rise from 1901 to 1990 of 1.2 ± 0.2 millimetres per year (90% confidence interval). Based on individual contributions tabulated in the Fifth Assessment Report of the Intergovernmental Panel on Climate Change, this estimate closes the twentieth-century sea-level budget. Our analysis, which combines tide gauge records with physics-based and model-derived geometries of the various contributing signals, also indicates that GMSL rose at a rate of 3.0 ± 0.7 millimetres per year between 1993 and 2010, consistent with prior estimates from tide gauge records.The increase in rate relative to the 1901-90 trend is accordingly larger than previously thought; this revision may affect some projections of future sea-level rise.
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From Rising Bubble to RNA/DNA and Bacteria
NASA Astrophysics Data System (ADS)
Marks, Roman; Cieszyńska, Agata; Wereszka, Marzena; Borkowski, Wojciech
2017-04-01
In this study we have focused on the movement of rising bubbles in a salty water body. Experiments reviled that free buoyancy movement of bubbles forces displacement of ions, located on the outer side of the bubble wall curvatures. During the short moment of bubble passage, all ions in the vicinity of rising bubble, are separated into anions that are gathered on the bubble upper half sphere and cations that slip along the bottom concave half-sphere of a bubble and develop a sub-bubble vortex. The principle of ions separation bases on the differences in displacement resistance. In this way, relatively heavier and larger, thus more resistant to displacement anions are gathered on the rising bubble upper half sphere, while smaller and lighter cations are assembled on the bottom half sphere and within the sub-bubble vortex. The acceleration of motion generates antiparallel rotary of bi-ionic domains, what implies that anions rotate in clockwise (CW) and cationic in counter-clockwise (CCW) direction. Then, both rotational systems may undergo splicing and extreme condensing by bi-pirouette narrowing of rotary. It is suggested that such double helix motion of bi-ionic domains creates RNA/DNA molecules. Finally, when the bubble reaches the water surface it burst and the preprocessed RNA/DNA matter is ejected into the droplets. Since that stage, droplet is suspended in positively charged troposphere, thus the cationic domain is located in the droplet center, whilst negative ions are attracted to configure the outer areola. According to above, the present study implies that the rising bubbles in salty waters may incept synergistic processing of matter resulting in its rotational/spherical organization that led to assembly of RNA/DNA molecules and bacteria cells.
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USDA-ARS?s Scientific Manuscript database
Two new species of Brachyodina Lindner, B. janestanleyae sp. n., is described from the Dominican Republic, and B. caymanensis sp. n. from Grand Cayman Island. A key to the species known from the Caribbean islands is provided....
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Methodology of project management at implementation of projects of high-rise construction
NASA Astrophysics Data System (ADS)
Papelniuk, Oksana
2018-03-01
High-rise construction is the perspective direction in urban development. An opportunity to arrange on rather small land plot a huge number of the living and commercial space makes high-rise construction very attractive for developers. However investment projects of high-rise buildings' construction are very expensive and complex that sets a task of effective management of such projects for the company builder. The best tool in this area today is the methodology of project management, which becomes a key factor of efficiency.
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Reduction of temperature rise in high-speed photography
NASA Technical Reports Server (NTRS)
Slater, Howard A.
1987-01-01
Information is provided on filtration with glass and infrared absorbing and reflecting filters. Glass and infrared filtration is a simple and effective method to reduce the radiation heat transfer associated with continuous high intensity tungsten lamps. The results of a filtration experiment are explained. The figures provide starting points for quantifying the effectiveness of various filters and associated light intensities. The combination of a spectrally selective reflector (hot or cold mirror) based on multilayer thin film principles and heat absorbing or infrared opaque glass results in the maximum reduction in temperature rise with a minimum of incident light loss. Use is recommended of a voltage regulator to further control temperature rise and incident light values.
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Reduction of temperature rise in high-speed photography
NASA Technical Reports Server (NTRS)
Slater, Howard A.
1988-01-01
Information is provided on filtration with glass and infrared absorbing and reflecting filters. Glass and infrared filtration is a simple and effective method to reduce the radiation heat transfer associated with continuous high intensity tungsten lamps. The results of a filtration experiment are explained. The figures provide starting points for quantifying the effectiveness of various filters and associated light intensities. The combination of a spectrally selective reflector (hot or cold mirror) based on multilayer thin film principles and heat absorbing or infrared opaque glass results in the maximum reduction in temperature rise with a minimum of incident light loss. Use is recommended of a voltage regulator to further control temperature rise and incident light values.
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Proton Fall or Bicarbonate Rise
Theparambil, Shefeeq M.; Weber, Tobias; Schmälzle, Jana; Ruminot, Ivàn; Deitmer, Joachim W.
2016-01-01
Glycolysis is the primary step for major energy production in the cell. There is strong evidence suggesting that glucose consumption and rate of glycolysis are highly modulated by cytosolic pH/[H+], but those can also be stimulated by an increase in the intracellular [HCO3−]. Because proton and bicarbonate shift concomitantly, it remained unclear whether enhanced glucose consumption and glycolytic rate were mediated by the changes in intracellular [H+] or [HCO3−]. We have asked whether glucose metabolism is enhanced by either a fall in intracellular [H+] or a rise in intracellular [HCO3−], or by both, in mammalian astrocytes. We have recorded intracellular glucose in mouse astrocytes using a FRET-based nanosensor, while imposing different intracellular [H+] and [CO2]/[HCO3−]. Glucose consumption and glycolytic rate were augmented by a fall in intracellular [H+], irrespective of a concomitant rise or fall in intracellular [HCO3−]. Transport of HCO3− into and out of astrocytes by the electrogenic sodium bicarbonate cotransporter (NBCe1) played a crucial role in causing changes in intracellular pH and [HCO3−], but was not obligatory for the pH-dependent changes in glucose metabolism. Our results clearly show that it is the cytosolic pH that modulates glucose metabolism in cortical astrocytes, and possibly also in other cell types. PMID:27422823
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HiRISE Observations of the Polar Regions of Mars
NASA Astrophysics Data System (ADS)
Herkenhoff, K. E.; Byrne, S.; Fishbaugh, K.; Russell, P.; Fortezzo, C.; McEwen, A.
2008-12-01
Digital elevation models (DEMs) derived from MRO HiRISE stereo images allow meter-scale topographic measurements in the north polar layered deposits (NPLD) and distinction of slope vs. albedo effects on apparent brightness of individual layers. HiRISE images do not show thin layers at the limit of resolution. Rather, fine layering, if it exists, appears to have been obscured by a more dust-rich mantling deposit which shows signs of eolian erosion and slumping. Stratigraphic sequences within the NPLD appear to be repeated within exposures observed by HiRISE, indicative of a record of periodic climate changes. Granular flows sourced from within the dark, basal unit are suggestive of, but do not require, the presence of water during their formation. Active mass wasting of frost and dust has been observed on steep NPLD scarps in early spring, similar to dry, loose snow avalanches on terrestrial slopes. Bright and dark streaks are seen to evolve during the northern summer, evidence for active eolian redistribution of frost and perhaps dark (non- volatile) material. Relatively dark reddish patches observed within the north polar residual cap during the summer indicate that the cap is very thin (<1 m) or more transparent in places. HiRISE images of exposures of the south polar layered deposits (SPLD) show rectilinear fractures that are continuous across several layers and whose orientation is not affected by the topography of the exposure, suggesting that they were formed before erosion of the SPLD. They appear to extend laterally and vertically through the SPLD, like a joint set. While NPLD tectonism appears limited to isolated grabens, several faults have been observed by HiRISE in the SPLD, showing structural details including reverse fault splays that merge into bedding planes and possible evidence for thrust duplication. The faults may be the result of basal sliding (decollements) ramping into thrust faults near the margin of the SPLD.
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Rise of Air Bubbles in Aircraft Lubricating Oils
NASA Technical Reports Server (NTRS)
Robinson, J. V.
1950-01-01
Lubricating and antifoaming additives in aircraft lubricating oils may impede the escape of small bubbles from the oil by forming shells of liquid with a quasi-solid or gel structure around the bubbles. The rates of rise of small air bubbles, up to 2 millimeters in diameter, were measured at room temperature in an undoped oil, in the same oil containing foam inhibitors, and in an oil containing lubricating additives. The apparent diameter of the air bubbles was measured visually through an ocular micrometer on a traveling telescope. The bubbles in the undoped oil obeyed Stokes' Law, the rate of rise being proportional to the square of the apparent diameter and inversely proportional to the viscosity of the oil. The bubbles in the oils containing lubricating additives or foam inhibitors rose more slowly than the rate predicted by Stokes 1 Law from the apparent diameter, and the rate of rise decreased as the length of path the bubbles traveled increased. A method is derived to calculate the thickness of the liquid shell which would have to move with the bubbles in the doped oils to account for the abnoi'I!l8.lly slow velocity. The maximum thickness of this shell, calculated from the velocities observed, was equal to the bubble radius.
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How mangrove forests adjust to rising sea level
Krauss, Ken W.; McKee, Karen L.; Lovelock, Catherine E.; Cahoon, Donald R.; Saintilan, Neil; Reef, Ruth; Chen, Luzhen
2014-01-01
Mangroves are among the most well described and widely studied wetland communities in the world. The greatest threats to mangrove persistence are deforestation and other anthropogenic disturbances that can compromise habitat stability and resilience to sea-level rise. To persist, mangrove ecosystems must adjust to rising sea level by building vertically or become submerged. Mangroves may directly or indirectly influence soil accretion processes through the production and accumulation of organic matter, as well as the trapping and retention of mineral sediment. In this review, we provide a general overview of research on mangrove elevation dynamics, emphasizing the role of the vegetation in maintaining soil surface elevations (i.e. position of the soil surface in the vertical plane). We summarize the primary ways in which mangroves may influence sediment accretion and vertical land development, for example, through root contributions to soil volume and upward expansion of the soil surface. We also examine how hydrological, geomorphological and climatic processes may interact with plant processes to influence mangrove capacity to keep pace with rising sea level. We draw on a variety of studies to describe the important, and often under-appreciated, role that plants play in shaping the trajectory of an ecosystem undergoing change.
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Constructive systems, load-bearing and enclosing structures of high-rise buildings
NASA Astrophysics Data System (ADS)
Anatol'evna Korol', Elena; Olegovna Kustikova, Yuliya
2018-03-01
As the height of the building increases, loads on load-carrying structures increase dramatically, and as a result of the development of high-rise construction, several structural systems of such buildings have been developed: frame, frame-frame, cross-wall, barrel, box-type, box-to-wall ("pipe in pipe", "Trumpet in the farm"), etc. In turn, the barrel systems have their own versions: cantilever support of the ceilings on the trunk, suspension of the outer part of the overlap to the upper carrying console "hanging house" or its support by means of the walls on the lower bearing cantilever, intermediate position of the supporting cantilevers in height to the floor, from a part of floors. The object of the study are the structural solutions of high-rise buildings. The subject of the study is the layout of structural schemes of high-rise buildings, taking into account the main parameters - altitude (height), natural climatic conditions of construction, materials of structural elements and their physical and mechanical characteristics. The purpose of the study is to identify the features and systematization of structural systems of high-rise buildings and the corresponding structural elements. The results of the research make it possible, at the stage of making design decisions, to establish rational parameters for the correspondence between the structural systems of high-rise buildings and their individual elements.
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Temperature rise during polymerization of different cavity liners and composite resins
Karatas, Ozcan; Turel, Verda; Bayindir, Yusuf Ziya
2015-01-01
Objective: The purpose of this study was to evaluate the thermal insulating properties of different light curing cavity liners and composite resins during light emitting diode (LED) curing. Materials and Methods: Sixty-four dentin discs, 1 mm thick and 8 mm in diameter, were prepared. Specimens were divided into four groups. Calcium hydroxide (Ca[OH]2), resin-modified glass ionomer cement, flowable composite and adhesive systems were applied to dentin discs according to the manufacturers’ instructions. The rise in temperature during polymerization with a LED curing unit (LCU) was measured using a K-type thermocouple connected to a data logger. Subsequently, all specimens were randomly divided into one of two groups. A silorane-based composite resin and a methacrylate-based composite resin were applied to the specimens. Temperature rise during polymerization of composite resins with LCU were then measured again. Data were analyzed using one-way ANOVA and post hoc Tukey analyses. Results: There were significant differences in temperature rise among the liners, adhesives, and composite resins (P < 0.05). Silorane-based composite resin exhibited significantly greater temperature rises than methacrylate-based resin (P < 0.05). The smallest temperature rises were observed in Ca(OH)2 specimens. Conclusion: Thermal insulating properties of different restorative materials are important factors in pulp health. Bonding agents alone are not sufficient to protect pulp from thermal stimuli throughout curing. PMID:26751112
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Better Medicare Cost Report data are needed to help hospitals benchmark costs and performance.
Magnus, S A; Smith, D G
2000-01-01
To evaluate costs and achieve cost control in the face of new technology and demands for efficiency from both managed care and governmental payers, hospitals need to benchmark their costs against those of other comparable hospitals. Since they typically use Medicare Cost Report (MCR) data for this purpose, a variety of cost accounting problems with the MCR may hamper hospitals' understanding of their relative costs and performance. Managers and researchers alike need to investigate the validity, accuracy, and timeliness of the MCR's cost accounting data.
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Morphology of Shatsky Rise oceanic plateau from high resolution bathymetry
NASA Astrophysics Data System (ADS)
Zhang, Jinchang; Sager, William W.; Durkin, William J.
2017-06-01
Newly collected, high resolution multi-beam sonar data are combined with previous bathymetry data to produce an improved bathymetric map of Shatsky Rise oceanic plateau. Bathymetry data show that two massifs within Shatsky Rise are immense central volcanoes with gentle flank slopes declining from a central summit. Tamu Massif is a slightly elongated, dome-like volcanic edifice; Ori Massif is square shaped and smaller in area. Several down-to-basin normal faults are observed on the western flank of the massifs but they do not parallel the magnetic lineations, indicating that these faults are probably not related to spreading ridge faulting. Moreover, the faults are observed only on one side of the massifs, which is contrary to expectations from a mechanism of differential subsidence around the massif center. Multi-beam data show many small secondary cones with different shapes and sizes that are widely-distributed on Shatsky Rise massifs, which imply small late-stage magma sources scattered across the surface of the volcanoes in the form of lava flows or explosive volcanism. Erosional channels occur on the flanks of Shatsky Rise volcanoes due to mass wasting and display evidence of down-slope sediment movement. These channels are likely formed by sediments spalling off the edges of summit sediment cap.
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Tidal wetland stability in the face of human impacts and sea-level rise.
Kirwan, Matthew L; Megonigal, J Patrick
2013-12-05
Coastal populations and wetlands have been intertwined for centuries, whereby humans both influence and depend on the extensive ecosystem services that wetlands provide. Although coastal wetlands have long been considered vulnerable to sea-level rise, recent work has identified fascinating feedbacks between plant growth and geomorphology that allow wetlands to actively resist the deleterious effects of sea-level rise. Humans alter the strength of these feedbacks by changing the climate, nutrient inputs, sediment delivery and subsidence rates. Whether wetlands continue to survive sea-level rise depends largely on how human impacts interact with rapid sea-level rise, and socio-economic factors that influence transgression into adjacent uplands.
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NASA Astrophysics Data System (ADS)
Li, Rong; Jones, Brian
2014-12-01
On Grand Cayman, the Pleistocene Ironshore Formation consists of six unconformity-bounded units of limestones that have been partially or completely altered to calcite by post-depositional meteoric diagenesis. In order to examine the diagenetic history from the perspective of geochemical elements, the concentrations of minor element (Sr, Na, Mg), trace elements (Ba, Fe, Mn, Al, Si), and rare-earth elements (REE) and yttrium (Y) were determined for 105 corals and 84 matrices collected from the Rogers Wreck Point (RWP), Western Onshore area (WO), and offshore George Town (GT) areas. With the transformation of aragonite to calcite, the Sr, Na, and Ba values decreased, but Mg increased, which are indicative of diagenetic alteration in an open water system. Due to intrinsic "vital effects" and the extrinsic diagenetic environment, the variations of Sr, Na, Ba, and Mg concentrations between Acropora and Montastrea from the GT area are different to those of their counterparts from RWP and WO. The signatures of Sr, Na, Ba, and Mg are in good agreement with the diagenetic history as determined from petrographic and stable isotopic criteria. The REE + Y (REY) concentrations (ΣREY) are higher in the matrices (0.2-6.9 ppm, average 2.6 ppm) than in the associated corals (0.1-5.4 ppm, average 0.6 ppm). Shale-normalized REY patterns of the Pleistocene Ironshore Formation are similar to those of oxygenated seawater, which are characterized by (1) light REE depletion relative to heavy REE (average DySN/SmSN = 1.7, n = 35), (2) positive La anomalies (average Pr/Pr* = 1.17, n = 53), and (3) negative Ce anomalies (average Ce/Ce* = 0.49, n = 53). The preserved seawater-like REY distribution pattern, the lack of correlation between ΣREY and mineralogy, and the lack of correlation between ΣREY and diagenesis-sensitive stable oxygen isotope (δ18O) indicate that meteoric diagenesis did not have a major impact on the REY distribution patterns. The matrices and corals in the GT area
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Study on drag coefficient of rising bubble in still water
NASA Astrophysics Data System (ADS)
Shi, M. Y.; Qi, Mei; Yi, C. G.; Liu, D. Y.; Zhang, K. X.
2017-09-01
Research on the behavior of a rising bubble in still water is on the basis of Newton's theory of classical mechanics. Develop a calculation analysis and an experimental process of bubble rising behavior in order to search for an appropriate way of valuing drag coefficient, which is the key element toward this issue. Analyze the adaptability of the drag coefficient; compare the theoretical model to the real experimental model of rising bubble behavior. The result turns out that the change rate of radius could be ignored according to the analysis; the acceleration phase is transient; final velocity and the diameter of bubble do relate to the drag coefficient, but have no obvious relation with the depth of water. After series of inference analysis of the bubble behavior and experimental demonstration, a new drag coefficient and computing method is proposed.
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Technological innovations and the rise of social inequalities in health.
Weiss, Daniel; Eikemo, Terje Andreas
2017-11-01
Social inequalities in health have been categorised as a human-rights issue that requires action. Unfortunately, these inequalities are on the rise in many countries, including welfare states. Various theories have been offered to explain the persistence (and rise) of these inequalities over time, including the social determinants of health and fundamental cause theory. Interestingly, the rise of modern social inequalities in health has come at a time of great technological innovation. This article addresses whether these technological innovations are significantly influencing the persistence of modern social inequalities in health. A theoretical argument is offered for this potential connection and is discussed alongside the typical social determinants of health perspective and the increasingly popular fundamental cause perspective. This is followed by a proposed research agenda for further investigation of the potential role that technological innovations may play in influencing social inequalities in health.
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Timescales for detecting a significant acceleration in sea level rise
Haigh, Ivan D.; Wahl, Thomas; Rohling, Eelco J.; Price, René M.; Pattiaratchi, Charitha B.; Calafat, Francisco M.; Dangendorf, Sönke
2014-01-01
There is observational evidence that global sea level is rising and there is concern that the rate of rise will increase, significantly threatening coastal communities. However, considerable debate remains as to whether the rate of sea level rise is currently increasing and, if so, by how much. Here we provide new insights into sea level accelerations by applying the main methods that have been used previously to search for accelerations in historical data, to identify the timings (with uncertainties) at which accelerations might first be recognized in a statistically significant manner (if not apparent already) in sea level records that we have artificially extended to 2100. We find that the most important approach to earliest possible detection of a significant sea level acceleration lies in improved understanding (and subsequent removal) of interannual to multidecadal variability in sea level records. PMID:24728012
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States' Budgets Reflect Rising Tax Collections
ERIC Educational Resources Information Center
Hoff, David J.
2005-01-01
Many state budgets are reaping the benefits of tax revenues that are rising faster than at any time since the economic slowdown ended. Overall tax collections by states rose by 11.7 percent in the first quarter of 2005, giving the legislatures extra cash to shore up school aid, increase teacher pay, and finance new initiatives such as full-day…
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Mars Structural and Stratigraphic Mapping along the Coprates Rise
NASA Technical Reports Server (NTRS)
Saunders, R Stephen
2009-01-01
This geologic mapping project supports a topical study of structures in east Thaumasia associated with the Coprates rise. The study examines cuesta-like features on the east flank of the Coprates rise first identified by Saunders et al. [1]. Mapping combines detailed local stratigraphy, structural geology and topography. Hogbacks and cuestas indicate erosion of tilted rock units. The extent of the erosion will be determined in the course of the mapping. The region of interest lies along the eastern margin of Thaumasia bounded by latitudes -15 and -35 and longitudes 50 to 70 W (Figure 1). Three MTM geologic quadrangles are being compiled for publication by the USGS (-20057, -25057, -30057). All existing data sources are used including THEMIS, MOC, CTX, HiRISE, MOLA and gravity, as well as higher level data available through the PDS data nodes at ASU, UA and Washington University. The extremely valuable ASU JMARS tools are used for analysis of many of the data sets. ArcGIS software has been obtained and is being learned for the map compilation.
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NASA Astrophysics Data System (ADS)
Chang, Wengui; Shen, Yuhua; Xie, Anjian; Liu, Xue
2010-04-01
Gemini surfactants, double sodium α-sulfonic polyethylene glycol laurate (abbreviated C 12-PEG-C 12), were prepared and applied as soft templates in the controlled synthesis of BaCrO 4 and PbCrO 4 micro/nanocrystals. The template effects were investigated by adjusting the length of the spacer, using PEG400 and PEG4000, of the Gemini surfactant. The results indicated that the size and morphology of BaCrO 4 and PbCrO 4 micro/nanocrystals varied with the change in spacer length of C 12-PEG-C 12, suggesting that the different lengths of the polyethylene glycol group spacers in the Gemini surfactants played a key role in determining the size and shape of the MCrO 4 micro/nanoparticles. The dynamic process of the formation of the novel morphology BaCrO 4 crystals showed that the morphology grew from a round-bar polyhedron, to regular polyhedron, to approximate octahedron to a uniform pistachio nut shape. The growth mechanism of the BaCrO 4 micro/nanocrystals was explained that C 12-PEG-C 12 had a greater interfacial adsorption and would effectively control the shape evolution during the crystal growth, while PbCrO 4 could be explained that the Gemini surfactants can undergo liquid-crystalline phase transitions with long channels providing a soft template effect and derived the nanorods formation. Room temperature fluorescence spectra were studied and these showed that the pistachio-shaped BaCrO 4 microcrystals and PbCrO 4 nanorods possess photoactive luminescence properties with emission peaks at 470 and 549 nm, respectively.
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Influence of early rising on performance in tasks requiring attention and memory.
Kumaran, V Shankar; Raghavendra, Bhat Ramachandra; Manjunath, Nandi Krishnamurthy
2012-01-01
Rising early in the morning has been a prescribed discipline of ancient Indian tradition. While there are no scientific studies comparing early rising volitionally versus circumstantially, selected studies on the latter (rising forcefully) have shown negative impact on an individual's peroformance. Hence the present study was undertaken to assess the influence of early rising (during Brahma-muhurtha) on tasks requiring attention and the ability to recall. Fifty four normal healthy male volunteers, with ages ranging from 16-22 years from a residential school were selected. They were randomly allocated to two groups (Brahma-muhurtha and control). They were assessed on day 1, day 10 and day 20 of the intervention, using a digit letter substitution task and verbal and spatial memory task. The Brahma-muhurtha group were asked to rise before 4:30 am in the morning based on the traditional Indian astrological calculations, while the control group were allowed to wake up just before 7 am which was their regular timing for waking. Brahma-muhurtha group after 20 days showed a significant improvement in the net scores for digit letter substitution task as well as scores for verbal and spatial memory tasks. The control group also showed an improvement in the memory task but not in the task requiring attentional processes. The present study suggests that rising early in the morning as described in ancient Indian tradition influences the process of attention and can improve the ability to recall.
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Intonational Rises and Dialog Acts in the Australian English Map Task.
ERIC Educational Resources Information Center
Fletcher, Janet; Stirling, Lesley; Mushin, Ilana; Wales, Roger
2002-01-01
Eight map task dialogs representative of general Australian English were coded for speaker turn and for dialog acts using a version of SWBD-DAMSL, a dialog act annotation scheme. High, low, simple, and complex rising tunes, and any corresponding dialog act codes were then compared. The Australian statement high rise (usually realized as a L…
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Doubling of coastal flooding frequency within decades due to sea-level rise
Vitousek, Sean; Barnard, Patrick L.; Fletcher, Charles H.; Frazer, Neil; Erikson, Li; Storlazzi, Curt D.
2017-01-01
Global climate change drives sea-level rise, increasing the frequency of coastal flooding. In most coastal regions, the amount of sea-level rise occurring over years to decades is significantly smaller than normal ocean-level fluctuations caused by tides, waves, and storm surge. However, even gradual sea-level rise can rapidly increase the frequency and severity of coastal flooding. So far, global-scale estimates of increased coastal flooding due to sea-level rise have not considered elevated water levels due to waves, and thus underestimate the potential impact. Here we use extreme value theory to combine sea-level projections with wave, tide, and storm surge models to estimate increases in coastal flooding on a continuous global scale. We find that regions with limited water-level variability, i.e., short-tailed flood-level distributions, located mainly in the Tropics, will experience the largest increases in flooding frequency. The 10 to 20 cm of sea-level rise expected no later than 2050 will more than double the frequency of extreme water-level events in the Tropics, impairing the developing economies of equatorial coastal cities and the habitability of low-lying Pacific island nations.
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Wei, Shiping; Cui, Hongpeng; Zhu, Youhai; Lu, Zhenquan; Pang, Shouji; Zhang, Shuai; Dong, Hailiang; Su, Xin
2018-05-01
Permafrost thaw can bring negative consequences in terms of ecosystems, resulting in permafrost collapse, waterlogging, thermokarst lake development, and species composition changes. Little is known about how permafrost thaw influences microbial community shifts and their activities. Here, we show that the dominant archaeal community shifts from Methanomicrobiales to Methanosarcinales in response to the permafrost thaw, and the increase in methane emission is found to be associated with the methanogenic archaea, which rapidly bloom with nearly tenfold increase in total number. The mcrA gene clone libraries analyses indicate that Methanocellales/Rice Cluster I was predominant both in the original permafrost and in the thawed permafrost. However, only species belonging to Methanosarcinales showed higher transcriptional activities in the thawed permafrost, indicating a shift of methanogens from hydrogenotrophic to partly acetoclastic methane-generating metabolic processes. In addition, data also show the soil texture and features change as a result of microbial reproduction and activity induced by this permafrost thaw. Those data indicate that microbial ecology under warming permafrost has potential impacts on ecosystem and methane emissions.
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On the design of high-rise buildings with a specified level of reliability
NASA Astrophysics Data System (ADS)
Dolganov, Andrey; Kagan, Pavel
2018-03-01
High-rise buildings have a specificity, which significantly distinguishes them from traditional buildings of high-rise and multi-storey buildings. Steel structures in high-rise buildings are advisable to be used in earthquake-proof regions, since steel, due to its plasticity, provides damping of the kinetic energy of seismic impacts. These aspects should be taken into account when choosing a structural scheme of a high-rise building and designing load-bearing structures. Currently, modern regulatory documents do not quantify the reliability of structures. Although the problem of assigning an optimal level of reliability has existed for a long time. The article shows the possibility of designing metal structures of high-rise buildings with specified reliability. Currently, modern regulatory documents do not quantify the reliability of high-rise buildings. Although the problem of assigning an optimal level of reliability has existed for a long time. It is proposed to establish the value of reliability 0.99865 (3σ) for constructions of buildings and structures of a normal level of responsibility in calculations for the first group of limiting states. For increased (construction of high-rise buildings) and reduced levels of responsibility for the provision of load-bearing capacity, it is proposed to assign respectively 0.99997 (4σ) and 0.97725 (2σ). The coefficients of the use of the cross section of a metal beam for different levels of security are given.
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Basement structures over Rio Grande Rise from gravity inversion
NASA Astrophysics Data System (ADS)
Constantino, Renata Regina; Hackspacher, Peter Christian; de Souza, Iata Anderson; Lima Costa, Iago Sousa
2017-04-01
The basement depth in the Rio Grande Rise (RGR), South Atlantic, is estimated from combining gravity data obtained from satellite altimetry, marine surveys, bathymetry, sediment thickness and crustal thickness information. We formulate a crustal model of the region by inverse gravity modeling. The effect of the sediment layer is evaluated using the global sediment thickness model of National Oceanic and Atmospheric Administration (NOAA) and fitting the sediment compaction model to observed density values from Deep Sea Drilling Project (DSDP) reports. The Global Relief Model ETOPO1 and constraining data from seismic interpretation on crustal thickness are integrated in the inversion process. The modeled Moho depth values vary between 6 and 27 km over the area, being thicker under the RGR and also in the direction of São Paulo Plateau. The inversion for the gravity-equivalent basement topography is applied to gravity residual data, which is free from the gravity effect of sediments and from the gravity effect of the estimated Moho interface. We find several short-wavelengths structures not present in the bathymetry data. Our model shows a rift crossing the entire Rio Grande Rise deeper than previously presented in literature, with depths up to 5 km in the East Rio Grande Rise (ERGR) and deeper in the West Rio Grande Rise (WRGR), reaching 6.4 km. An interesting NS structure that goes from 34°S and extends through de São Paulo Ridge may be related to the South Atlantic Opening and could reveal an extinct spreading center.
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High-rise construction in the Russian economy: modeling of management decisions
NASA Astrophysics Data System (ADS)
Miroshnikova, Tatyana; Taskaeva, Natalia
2018-03-01
The growth in the building industry, particularly in residential high-rise construction, is having considerable influence on the country's economic development. The scientific hypothesis of the research is that the execution of town-planning programs of high-rise construction depends to a large extent on the management of the provision of material resources for the construction of a millionth city, while the balance model is the most important tool for establishing and determining the ratio between supply and demand for material resources. In order to improve the efficiency of high-rise building management, it is proposed to develop a methodology for managing the provision of construction of large cities with material resources.
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The reaction mechanism of methyl-coenzyme M reductase: How an enzyme enforces strict binding order
Wongnate, Thanyaporn; Ragsdale, Stephen W.
2015-02-17
Methyl-coenzyme M reductase (MCR) is a nickel tetrahydrocorphinoid (coenzyme F430) containing enzyme involved in the biological synthesis and anaerobic oxidation of methane. MCR catalyzes the conversion of methyl-2-mercaptoethanesulfonate (methyl-SCoM) and N-7-mercaptoheptanoylthreonine phosphate (CoB 7SH) to CH 4 and the mixed disulfide CoBS-SCoM. In this study, the reaction of MCR from Methanothermobacter marburgensis, with its native substrates was investigated using static binding, chemical quench, and stopped-flow techniques. Rate constants were measured for each step in this strictly ordered ternary complex catalytic mechanism. Surprisingly, in the absence of the other substrate, MCR can bind either substrate; however, only one binary complex (MCR·methyl-SCoM)more » is productive whereas the other (MCR·CoB 7SH) is inhibitory. Moreover, the kinetic data demonstrate that binding of methyl-SCoM to the inhibitory MCR·CoB 7SH complex is highly disfavored ( Kd = 56 mM). However, binding of CoB 7SH to the productive MCR·methyl-SCoM complex to form the active ternary complex (CoB 7SH·MCR(Ni I)·CH 3SCoM) is highly favored ( Kd = 79 μM). Only then can the chemical reaction occur ( kobs = 20 s -1 at 25 °C), leading to rapid formation and dissociation of CH 4 leaving the binary product complex (MCR(Ni II)·CoB 7S -·SCoM), which undergoes electron transfer to regenerate Ni(I) and the final product CoBS-SCoM. In conclusion, this first rapid kinetics study of MCR with its natural substrates describes how an enzyme can enforce a strictly ordered ternary complex mechanism and serves as a template for identification of the reaction intermediates.« less
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Ice Shelf-Ocean Interactions Near Ice Rises and Ice Rumples
NASA Astrophysics Data System (ADS)
Lange, M. A.; Rückamp, M.; Kleiner, T.
2013-12-01
The stability of ice shelves depends on the existence of embayments and is largely influenced by ice rises and ice rumples, which act as 'pinning-points' for ice shelf movement. Of additional critical importance are interactions between ice shelves and the water masses underlying them in ice shelf cavities, particularly melting and refreezing processes. The present study aims to elucidate the role of ice rises and ice rumples in the context of climate change impacts on Antarctic ice shelves. However, due to their smaller spatial extent, ice rumples react more sensitively to climate change than ice rises. Different forcings are at work and need to be considered separately as well as synergistically. In order to address these issues, we have decided to deal with the following three issues explicitly: oceanographic-, cryospheric and general topics. In so doing, we paid particular attention to possible interrelationships and feedbacks in a coupled ice-shelf-ocean system. With regard to oceanographic issues, we have applied the ocean circulation model ROMBAX to ocean water masses adjacent to and underneath a number of idealized ice shelf configurations: wide and narrow as well as laterally restrained and unrestrained ice shelves. Simulations were performed with and without small ice rises located close to the calving front. For larger configurations, the impact of the ice rises on melt rates at the ice shelf base is negligible, while for smaller configurations net melting rates at the ice-shelf base differ by a factor of up to eight depending on whether ice rises are considered or not. We employed the thermo-coupled ice flow model TIM-FD3 to simulate the effects of several ice rises and one ice rumple on the dynamics of ice shelf flow. We considered the complete un-grounding of the ice shelf in order to investigate the effect of pinning points of different characteristics (interior or near calving front, small and medium sized) on the resulting flow and stress fields
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Baïkoff, Georges; Bourgeon, Grégoire; Jodai, Horacio Jitsuo; Fontaine, Aline; Lellis, Fernando Viera; Trinquet, Laure
2005-04-01
To validate the theory that crystalline lens rise can be used as a safety criterion to prevent pigment dispersion in eyes with an Artisan phakic intraocular lens (IOL) (Ophtec BV). Monticelli Clinic, Marseilles, France. A comparative analysis of crystalline lens rise in 9 eyes with pigment dispersion and 78 eyes without dispersion was performed. All eyes had previous implantation of an Artisan IOL. Anterior segment imaging was done using an anterior chamber optical coherence tomography (AC OCT) prototype. Crystalline lens rise was defined by the distance between the anterior pole of the crystalline lens and the horizontal plane joining the opposite iridocorneal recesses. The study confirmed that crystalline lens rise can be considered a safety criterion for implantation of Artisan-type phakic IOLs. The higher the crystalline lens rise, the greater the risk for developing pigment dispersion in the area of the pupil. This complication occurred more frequently in hyperopic eyes than in myopic eyes. Results indicate there is little or no risk for pigment dispersion if the rise is less than 600 microm; 67% of eyes with a rise of 600 microm or more developed pupillary pigment dispersion. In some cases in which the IOL was loosely fixated, there was no traction on the iris root and dispersion was prevented or delayed. Crystalline lens rise should be considered a new safety criterion for Artisan phakic IOL implantation and should also be applied to other types of phakic IOLs. The distance remaining between the crystalline lens rise and a 600 microm theoretical safety level allows one to calculate how long the IOL can safely remain in the eye.
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Fire Problems in High-Rise Buildings. California Fire Service Training Program.
ERIC Educational Resources Information Center
California State Dept. of Education, Sacramento. Bureau of Industrial Education.
Resulting from a conference concerned with high-rise fire problems, this manual has been prepared as a fire department training manual and as a reference for students enrolled in fire service training courses. Information is provided for topics dealing with: (1) Typical Fire Problems in High-Rise Buildings, (2) Heat, (3) Smoke and Fire Gases, (4)…
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NASA Astrophysics Data System (ADS)
Shin, J.; Kim, K.-H.; Lee, K.-K.
2012-04-01
Sea level rise, which is one of the representative phenomena of climate changes caused by global warming, can affect groundwater system. The rising trend of the sea level caused by the global warming is reported to be about 3 mm/year for the most recent 10 year average (IPCC, 2007). The rate of sea level rise around the Korean peninsula is reported to be 2.30±2.22 mm/yr during the 1960-1999 period (Cho, 2002) and 2.16±1.77 mm/yr (Kim et al., 2009) during the 1968-2007 period. Both of these rates are faster than the 1.8±0.5 mm/yr global average for the similar 1961-2003 period (IPCC, 2007). In this study, we analyzed changes in the groundwater environment affected by the sea level rise by using an analytical methodology. We tried to find the most effective parameters of groundwater amount change in order to estimate the change in fresh water amount in coastal groundwater. A hypothetical island model of a cylindrical shape in considered. The groundwater storage change is bi-directional as the sea level rises according to the natural and hydrogeological conditions. Analysis of the computation results shows that topographic slope and hydraulic conductivity are the most sensitive factors. The contributions of the groundwater recharge rate and the thickness of aquifer below sea level are relatively less effective. In the island with steep seashore slopes larger than 1~2 degrees or so, the storage amount of fresh water in a coastal area increases as sea level rises. On the other hand, when sea level drops, the storage amount decreases. This is because the groundwater level also rises with the rising sea level in steep seashores. For relatively flat seashores, where the slope is smaller than around 1-2 degrees, the storage amount of coastal fresh water decreases when the sea level rises because the area flooded by the rising sea water is increased. The volume of aquifer fresh water in this circumstance is greatly reduced in proportion to the flooded area with the sea
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Exposure to rising inequality shapes Americans’ opportunity beliefs and policy support
McCall, Leslie; Burk, Derek; Laperrière, Marie; Richeson, Jennifer A.
2017-01-01
Economic inequality has been on the rise in the United States since the 1980s and by some measures stands at levels not seen since before the Great Depression. Although the strikingly high and rising level of economic inequality in the nation has alarmed scholars, pundits, and elected officials alike, research across the social sciences repeatedly concludes that Americans are largely unconcerned about it. Considerable research has documented, for instance, the important role of psychological processes, such as system justification and American Dream ideology, in engendering Americans’ relative insensitivity to economic inequality. The present work offers, and reports experimental tests of, a different perspective—the opportunity model of beliefs about economic inequality. Specifically, two convenience samples (study 1, n = 480; and study 2, n = 1,305) and one representative sample (study 3, n = 1,501) of American adults were exposed to information about rising economic inequality in the United States (or control information) and then asked about their beliefs regarding the roles of structural (e.g., being born wealthy) and individual (e.g., hard work) factors in getting ahead in society (i.e., opportunity beliefs). They then responded to policy questions regarding the roles of business and government actors in reducing economic inequality. Rather than revealing insensitivity to rising inequality, the results suggest that rising economic inequality in contemporary society can spark skepticism about the existence of economic opportunity in society that, in turn, may motivate support for policies designed to redress economic inequality. PMID:28831007
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Exposure to rising inequality shapes Americans' opportunity beliefs and policy support.
McCall, Leslie; Burk, Derek; Laperrière, Marie; Richeson, Jennifer A
2017-09-05
Economic inequality has been on the rise in the United States since the 1980s and by some measures stands at levels not seen since before the Great Depression. Although the strikingly high and rising level of economic inequality in the nation has alarmed scholars, pundits, and elected officials alike, research across the social sciences repeatedly concludes that Americans are largely unconcerned about it. Considerable research has documented, for instance, the important role of psychological processes, such as system justification and American Dream ideology, in engendering Americans' relative insensitivity to economic inequality. The present work offers, and reports experimental tests of, a different perspective-the opportunity model of beliefs about economic inequality. Specifically, two convenience samples (study 1, n = 480; and study 2, n = 1,305) and one representative sample (study 3, n = 1,501) of American adults were exposed to information about rising economic inequality in the United States (or control information) and then asked about their beliefs regarding the roles of structural (e.g., being born wealthy) and individual (e.g., hard work) factors in getting ahead in society (i.e., opportunity beliefs). They then responded to policy questions regarding the roles of business and government actors in reducing economic inequality. Rather than revealing insensitivity to rising inequality, the results suggest that rising economic inequality in contemporary society can spark skepticism about the existence of economic opportunity in society that, in turn, may motivate support for policies designed to redress economic inequality.
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The Rising Cost of Private Higher Education.
ERIC Educational Resources Information Center
Suttle, J. Lloyd
1983-01-01
The informational and analytical bases by which Yale University sets tuition levels and long-term pricing policies are illustrated. The rising cost of private higher education is discussed, considering historical trends, inflation, the institution's financial condition, comparative costs from other schools, and effect on enrollment. (MSE)
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Sea-level rise in New Jersey over the past 5000 years: Implications to anthropogenic changes
Miller, Kenneth G.; Sugarman, Peter J.; Browning, James V.; Horton, Benjamin P.; Stanley, Alissa; Kahn, Alicia; Uptegrove, Jane; Aucott, Michael
2009-01-01
We present a mid to late Holocene sea-level record derived from drilling the New Jersey coast that shows a relatively constant rise of 1.8??mm/yr from ~ 5000 to 500 calibrated calendar years before present (yrBP). This contrasts with previous New Jersey estimates that showed only 0.5??mm/yr rise since 2000??yrBP. Comparison with other Mid-Atlantic sea-level records (Delaware to southern New England) indicates surprising uniformity considering different proximities to the peripheral bulge of the Laurentide ice sheet, with a relative rise throughout the region of ~ 1.7-1.9??mm/yr since ~ 5000??yrBP. This regional sea-level rise includes both: 1) global sea-level (eustatic) rise; and 2) far-field geoidal subsidence (estimated as ~ 0.8-1.4??mm/yr today) due to removal of the Laurentide ice sheet and water loading. Correcting for geoidal subsidence, the U.S. east coast records suggest a global sea-level (eustatic) rise of ~ 0.4-1.0??mm/yr (with a best estimate of 0.7 ?? 0.3??mm/yr) since 5000??yrBP. Comparison with other records provides a best estimate of pre-anthropogenic global sea-level rise of < 1.0??mm/yr from 5000 until ~ 200??yrBP. Tide gauge data indicate a 20th century rate of eustatic rise of 1.8??mm/yr, whereas both tide gauge and satellite data suggest an increase in the rate of rise to ~ 3.3??mm/yr from 1993-2006 AD. This indicates that the modern rise (~ 3.3??mm/yr) is significantly higher than the pre-anthropogenic rise (0.7 ?? 0.3??mm/yr). ?? 2008 Elsevier B.V. All rights reserved.
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Pragasam, Agila K.; Shankar, Chaitra; Veeraraghavan, Balaji; Biswas, Indranil; Nabarro, Laura E. B.; Inbanathan, Francis Y.; George, Biju; Verghese, Santhosh
2017-01-01
Colistin has long been a reserve drug used for the treatment of carbapenem resistant Klebsiella pneumoniae. Carbapenem resistance in K. pneumoniae has been increasing and is as high as 44% in India. Although a reserve agent, with rise in rates of resistance to carbapenems, the usage of colistin has increased over the years leading to slow emergence of resistance. Colistin resistance is mainly mediated by the alteration in the LPS of bacterial outer membrane with the addition of L-Ara4-N and PEtN molecules. These alterations are mediated by mutations in several genes involved in lipidA modifications and most commonly mutations in mgrB gene has been reported. Recently there is emergence of plasmid mediated resistance due to mcr-1 and mcr-2 genes which poses a threat for the rapid global spread. This study aims at characterizing eight colistin resistant K. pneumoniae from bacteremia by whole genome sequencing. Eight K. pneumoniae were isolated from blood culture during 2013 and 2014 at the Department of Clinical Microbiology, Christian Medical College, India. Antimicrobial susceptibility testing was performed and minimum inhibitory concentration (MIC) was determined for colistin and polymyxin B by broth-micro dilution method. Whole genome sequencing was performed using Ion Torrent and the genome of all eight isolates was analyzed. The eight isolates were resistant to all the antimicrobials expect tigecycline. MIC of colistin and polymyxin B were ranged from 4 to 1024 μg/ml and 0.5 to 2048 μg/ml respectively. Multiple mutations were observed in the chromosomal genes involved in lipid A modifications. mcr-1 and mcr-2 gene was absent in all the isolates. The most significant were mutations in mgrB gene. Among the eight isolates, four, three and one were belonged to sequence types ST 231, ST14 and ST147 respectively. Seven isolates had blaOXA−48 like, one co-expressed blaNDM−1 and blaOXA−48 like genes leading to carbapenem resistance. Overall, multiple numbers of
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Pragasam, Agila K; Shankar, Chaitra; Veeraraghavan, Balaji; Biswas, Indranil; Nabarro, Laura E B; Inbanathan, Francis Y; George, Biju; Verghese, Santhosh
2016-01-01
Colistin has long been a reserve drug used for the treatment of carbapenem resistant Klebsiella pneumoniae . Carbapenem resistance in K. pneumoniae has been increasing and is as high as 44% in India. Although a reserve agent, with rise in rates of resistance to carbapenems, the usage of colistin has increased over the years leading to slow emergence of resistance. Colistin resistance is mainly mediated by the alteration in the LPS of bacterial outer membrane with the addition of L-Ara4-N and PEtN molecules. These alterations are mediated by mutations in several genes involved in lipidA modifications and most commonly mutations in mgrB gene has been reported. Recently there is emergence of plasmid mediated resistance due to mcr-1 and mcr-2 genes which poses a threat for the rapid global spread. This study aims at characterizing eight colistin resistant K. pneumoniae from bacteremia by whole genome sequencing. Eight K. pneumoniae were isolated from blood culture during 2013 and 2014 at the Department of Clinical Microbiology, Christian Medical College, India. Antimicrobial susceptibility testing was performed and minimum inhibitory concentration (MIC) was determined for colistin and polymyxin B by broth-micro dilution method. Whole genome sequencing was performed using Ion Torrent and the genome of all eight isolates was analyzed. The eight isolates were resistant to all the antimicrobials expect tigecycline. MIC of colistin and polymyxin B were ranged from 4 to 1024 μg/ml and 0.5 to 2048 μg/ml respectively. Multiple mutations were observed in the chromosomal genes involved in lipid A modifications. mcr-1 and mcr-2 gene was absent in all the isolates. The most significant were mutations in mgrB gene. Among the eight isolates, four, three and one were belonged to sequence types ST 231, ST14 and ST147 respectively. Seven isolates had bla OXA-48 like , one co-expressed bla NDM-1 and bla OXA-48 like genes leading to carbapenem resistance. Overall, multiple numbers of
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Non-target-site resistance to ALS inhibitors in waterhemp (Amaranthus tuberculatus)
USDA-ARS?s Scientific Manuscript database
A waterhemp population (MCR) previously characterized as resistant to 4-hyroxyphenylpyruvate dioxygenase (HPPD) and photosystem II (PSII) inhibitors was found to have two different resistance responses to acetolactate synthase (ALS) inhibitors. Plants from the MCR population exhibiting high resistan...
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Rising synchrony controls western North American ecosystems
Black, Bryan A.; van der Sleen, Peter; Di Lorenzo, Emanuele; Griffin, Daniel; Sydeman, William J.; Dunham, Jason B.; Rykaczewski, Ryan R.; Garcia-Reyes, Marisol; Safeeq, Mohammad; Arismendi, Ivan; Bograd, Steven J.
2018-01-01
Along the western margin of North America, the winter expression of the North Pacific High (NPH) strongly influences interannual variability in coastal upwelling, storm track position, precipitation, and river discharge. Coherence among these factors induces covariance among physical and biological processes across adjacent marine and terrestrial ecosystems. Here, we show that over the past century the degree and spatial extent of this covariance (synchrony) has substantially increased, and is coincident with rising variance in the winter NPH. Furthermore, centuries‐long blue oak (Quercus douglasii) growth chronologies sensitive to the winter NPH provide robust evidence that modern levels of synchrony are among the highest observed in the context of the last 250 years. These trends may ultimately be linked to changing impacts of the El Niño Southern Oscillation on mid‐latitude ecosystems of North America. Such a rise in synchrony may destabilize ecosystems, expose populations to higher risks of extinction, and is thus a concern given the broad biological relevance of winter climate to biological systems.
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Coastal vulnerability assessment of Dry Tortugas National Park (DRTO) to sea-level rise
Pendleton, Elizabeth A.; Thieler, E. Robert; Williams, S. Jeffress
2005-01-01
A coastal vulnerability index (CVI) was used to map the relative vulnerability of the coast to future sea-level rise within Dry Tortugas National Park in Florida. The CVI ranks the following in terms of their physical contribution to sea-level rise-related coastal change: geomorphology, regional coastal slope, rate of relative sea-level rise, historical shoreline change rates, mean tidal range and mean significant wave height. The rankings for each input variable were combined and an index value calculated for 1-minute grid cells covering the park. The CVI highlights those regions where the physical effects of sea-level rise might be the greatest. This approach combines the coastal system's susceptibility to change with its natural ability to adapt to changing environmental conditions, yielding a quantitative, although relative, measure of the park's natural vulnerability to the effects of sea-level rise. The CVI provides an objective technique for evaluation and long-term planning by scientists and park managers. Dry Tortugas National Park (DRTO) consists of relatively stable to washover-dominated portions of carbonate beach and man-made fortification. The areas within Dry Tortugas that are likely to be most vulnerable to sea-level rise are those with the highest rates of shoreline erosion and the highest wave energy.
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Rise time analysis of pulsed klystron-modulator for efficiency improvement of linear colliders
NASA Astrophysics Data System (ADS)
Oh, J. S.; Cho, M. H.; Namkung, W.; Chung, K. H.; Shintake, T.; Matsumoto, H.
2000-04-01
In linear accelerators, the periods during the rise and fall of a klystron-modulator pulse cannot be used to generate RF power. Thus, these periods need to be minimized to get high efficiency, especially in large-scale machines. In this paper, we present a simplified and generalized voltage rise time function of a pulsed modulator with a high-power klystron load using the equivalent circuit analysis method. The optimum pulse waveform is generated when this pulsed power system is tuned with a damping factor of ˜0.85. The normalized rise time chart presented in this paper allows one to predict the rise time and pulse shape of the pulsed power system in general. The results can be summarized as follows: The large distributed capacitance in the pulse tank and operating parameters, Vs× Tp , where Vs is load voltage and Tp is the pulse width, are the main factors determining the pulse rise time in the high-power RF system. With an RF pulse compression scheme, up to ±3% ripple of the modulator voltage is allowed without serious loss of compressor efficiency, which allows the modulator efficiency to be improved as well. The wiring inductance should be minimized to get the fastest rise time.
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Coastal vulnerability assessment of Cape Hatteras National Seashore (CAHA) to sea-level rise
Pendleton, Elizabeth A.; Theiler, E. Robert; Williams, S. Jeffress
2005-01-01
A coastal vulnerability index (CVI) was used to map the relative vulnerability of the coast to future sea-level rise within Cape Hatteras National Seashore (CAHA) in North Carolina. The CVI ranks the following in terms of their physical contribution to sea-level rise-related coastal change: geomorphology, regional coastal slope, rate of relative sea-level rise, historical shoreline change rates, mean tidal range, and mean significant wave height. The rankings for each variable were combined and an index value was calculated for 1-minute grid cells covering the park. The CVI highlights those regions where the physical effects of sea-level rise might be the greatest. This approach combines the coastal system's susceptibility to change with its natural ability to adapt to changing environmental conditions, yielding a quantitative, although relative, measure of the park's natural vulnerability to the effects of sea-level rise. The CVI provides an objective technique for evaluation and long-term planning by scientists and park managers. Cape Hatteras National Seashore consists of stable and washover dominated segments of barrier beach backed by wetland and marsh. The areas within Cape Hatteras that are likely to be most vulnerable to sea-level rise are those with the highest occurrence of overwash and the highest rates of shoreline change.
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Coastal Vulnerability Assessment of Padre Island National Seashore (PAIS) to Sea-Level Rise
Pendleton, Elizabeth A.; Thieler, E. Robert; Williams, S. Jeffress; Beavers, Rebecca S.
2004-01-01
A coastal vulnerability index (CVI) was used to map the relative vulnerability of the coast to future sea-level rise within Padre Island National Seashore in Texas. The CVI ranks the following in terms of their physical contribution to sea-level rise-related coastal change: geomorphology, regional coastal slope, rate of relative sea-level rise, shoreline change rates, mean tidal range and mean significant wave height. The rankings for each variable were combined and an index value calculated for 1-minute grid cells covering the park. The CVI highlights those regions where the physical effects of sea-level rise might be the greatest. This approach combines the coastal system's susceptibility to change with its natural ability to adapt to changing environmental conditions, yielding a quantitative, although relative, measure of the park's natural vulnerability to the effects of sea-level rise. The CVI provides an objective technique for evaluation and long-term planning by scientists and park managers. Padre Island National Seashore consists of stable to washover dominated portions of barrier beach backed by wetland, marsh, tidal flat, or grassland. The areas within Padre that are likely to be most vulnerable to sea-level rise are those with the highest occurrence of overwash and the highest rates of shoreline change.
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Land subsidence and relative sea-level rise in the southern Chesapeake Bay region
Eggleston, Jack; Pope, Jason
2013-01-01
The southern Chesapeake Bay region is experiencing land subsidence and rising water levels due to global sea-level rise; land subsidence and rising water levels combine to cause relative sea-level rise. Land subsidence has been observed since the 1940s in the southern Chesapeake Bay region at rates of 1.1 to 4.8 millimeters per year (mm/yr), and subsidence continues today. This land subsidence helps explain why the region has the highest rates of sea-level rise on the Atlantic Coast of the United States. Data indicate that land subsidence has been responsible for more than half the relative sea-level rise measured in the region. Land subsidence increases the risk of flooding in low-lying areas, which in turn has important economic, environmental, and human health consequences for the heavily populated and ecologically important southern Chesapeake Bay region. The aquifer system in the region has been compacted by extensive groundwater pumping in the region at rates of 1.5- to 3.7-mm/yr; this compaction accounts for more than half of observed land subsidence in the region. Glacial isostatic adjustment, or the flexing of the Earth’s crust in response to glacier formation and melting, also likely contributes to land subsidence in the region.
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Charmoy, Alexia; Würzner, Grégoire; Ruffieux, Christiane; Hasler, Christopher; Cachat, François; Waeber, Bernard; Burnier, Michel
2007-10-01
Cuff inflation at the arm is known to cause an instantaneous rise in blood pressure, which might be due to the discomfort of the procedure and might interfere with the precision of the blood pressure measurement. In this study, we compared the reactive rise in blood pressure induced by cuff inflation when the cuff was placed at the upper arm level and at the wrist. The reactive rise in systolic and diastolic blood pressure to cuff inflation was measured in 34 normotensive participants and 34 hypertensive patients. Each participant was equipped with two cuffs, one around the right upper arm (OMRON HEM-CR19, 22-32 cm) and one around the right wrist (OMRON HEM-CS 19, 17-22 cm; Omron Health Care Europe BV, Hoofddorp, The Netherlands). The cuffs were inflated in a double random order (maximal cuff pressure and position of the cuff) with two maximal cuff pressures: 180 and 240 mmHg. The cuffs were linked to an oscillometric device (OMRON HEM 907; Omron Health Care). Simultaneously, blood pressure was measured continuously at the middle finger of the left hand using photoplethysmography. Three measurements were made at each level of blood pressure at the arm and at the wrist, and the sequence of measurements was randomized. In normotensive participants, no significant difference was observed in the reactive rise in blood pressure when the cuff was inflated either at the arm or at the wrist irrespective of the level of cuff inflation. Inflating a cuff at the arm, however, induced a significantly greater rise in blood pressure than inflating it at the wrist in hypertensive participants for both systolic and diastolic pressures (P<0.01), and at both levels of cuff inflation. The blood pressure response to cuff inflation was independent of baseline blood pressure. The results show that in hypertensive patients, cuff inflation at the wrist produces a smaller reactive rise in blood pressure. The difference between the arm and the wrist is independent of the patient's level of
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Capillary rise between planar surfaces
NASA Astrophysics Data System (ADS)
Bullard, Jeffrey W.; Garboczi, Edward J.
2009-01-01
Minimization of free energy is used to calculate the equilibrium vertical rise and meniscus shape of a liquid column between two closely spaced, parallel planar surfaces that are inert and immobile. States of minimum free energy are found using standard variational principles, which lead not only to an Euler-Lagrange differential equation for the meniscus shape and elevation, but also to the boundary conditions at the three-phase junction where the liquid meniscus intersects the solid walls. The analysis shows that the classical Young-Dupré equation for the thermodynamic contact angle is valid at the three-phase junction, as already shown for sessile drops with or without the influence of a gravitational field. Integration of the Euler-Lagrange equation shows that a generalized Laplace-Young (LY) equation first proposed by O’Brien, Craig, and Peyton [J. Colloid Interface Sci. 26, 500 (1968)] gives an exact prediction of the mean elevation of the meniscus at any wall separation, whereas the classical LY equation for the elevation of the midpoint of the meniscus is accurate only when the separation approaches zero or infinity. When both walls are identical, the meniscus is symmetric about the midpoint, and the midpoint elevation is a more traditional and convenient measure of capillary rise than the mean elevation. Therefore, for this symmetric system a different equation is fitted to numerical predictions of the midpoint elevation and is shown to give excellent agreement for contact angles between 15° and 160° and wall separations up to 30mm . When the walls have dissimilar surface properties, the meniscus generally assumes an asymmetric shape, and significant elevation of the liquid column can occur even when one of the walls has a contact angle significantly greater than 90°. The height of the capillary rise depends on the spacing between the walls and also on the difference in contact angles at the two surfaces. When the contact angle at one wall is greater
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NASA Astrophysics Data System (ADS)
Quach, N.; Huang, T.; Boening, C.; Gill, K. M.
2016-12-01
Research related to sea level rise crosses multiple disciplines from sea ice to land hydrology. The NASA Sea Level Change Portal (SLCP) is a one-stop source for current sea level change information and data, including interactive tools for accessing and viewing regional data, a virtual dashboard of sea level indicators, and ongoing updates through a suite of editorial products that include content articles, graphics, videos, and animations. The architecture behind the SLCP makes it possible to integrate web content and data relevant to sea level change that are archived across various data centers as well as new data generated by sea level change principal investigators. The Extensible Data Gateway Environment (EDGE) is incorporated into the SLCP architecture to provide a unified platform for web content and science data discovery. EDGE is a data integration platform designed to facilitate high-performance geospatial data discovery and access with the ability to support multi-metadata standard specifications. EDGE has the capability to retrieve data from one or more sources and package the resulting sets into a single response to the requestor. With this unified endpoint, the Data Analysis Tool that is available on the SLCP can retrieve dataset and granule level metadata as well as perform geospatial search on the data. This talk focuses on the architecture that makes it possible to seamlessly integrate and enable discovery of disparate data relevant to sea level rise.
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Modeling Tidal Wetland Resiliency in the Face of Predicted Accelerated Sea-Level Rise
NASA Astrophysics Data System (ADS)
Schile, L. M.; Callaway, J.; Morris, J. T.; Kelly, M.
2014-12-01
Tidal wetland ecosystems are dynamic coastal habitats that, in California, often occur at the complex nexus of aquatic environments, diked and leveed baylands, and modified upland habitat. Because of their prime location and rich peat soil, many wetlands have been reduced, degraded, and/or destroyed, and yet their important role in carbon sequestration, nutrient and sediment filtering, and as habitat requires us to further examine their sustainability in light of predicted climate change. Predictions of climate change effects for the San Francisco Bay Estuary present a future with reduced summer freshwater input and increased sea levels. We examined the applicability and accuracy of the Marsh Equilibrium Model (MEM), a zero-dimensional model that models organic and inorganic accretion rates under a given rate of sea-level rise. MEM was calibrated using data collected from salt and brackish marshes in the San Francisco Bay Estuary to examine wetland resiliency under a range of sea-level rise and suspended sediment concentration scenarios. At sea-level rise rates 100 cm/century and lower, wetlands remained vegetated. Once sea levels rise above 100 cm, marshes begin to lose ability to maintain elevation, and the presence of adjacent upland habitat becomes increasingly important for marsh migration. The negative effects of sea-level rise on elevations were compounded as suspended sediment concentrations decreased. Results from this study emphasize that the wetland landscape in the bay is threatened with rising sea levels, and there are a limited number of wetlands that will be able to migrate to higher ground as sea levels rise.
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Finite difference modelling of the temperature rise in non-linear medical ultrasound fields.
Divall, S A; Humphrey, V F
2000-03-01
Non-linear propagation of ultrasound can lead to increased heat generation in medical diagnostic imaging due to the preferential absorption of harmonics of the original frequency. A numerical model has been developed and tested that is capable of predicting the temperature rise due to a high amplitude ultrasound field. The acoustic field is modelled using a numerical solution to the Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation, known as the Bergen Code, which is implemented in cylindrical symmetric form. A finite difference representation of the thermal equations is used to calculate the resulting temperature rises. The model allows for the inclusion of a number of layers of tissue with different acoustic and thermal properties and accounts for the effects of non-linear propagation, direct heating by the transducer, thermal diffusion and perfusion in different tissues. The effect of temperature-dependent skin perfusion and variation in background temperature between the skin and deeper layers of the body are included. The model has been tested against analytic solutions for simple configurations and then used to estimate temperature rises in realistic obstetric situations. A pulsed 3 MHz transducer operating with an average acoustic power of 200 mW leads to a maximum steady state temperature rise inside the foetus of 1.25 degrees C compared with a 0.6 degree C rise for the same transmitted power under linear propagation conditions. The largest temperature rise occurs at the skin surface, with the temperature rise at the foetus limited to less than 2 degrees C for the range of conditions considered.
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NASA Astrophysics Data System (ADS)
Voskresenskaya, Elena; Vorona-Slivinskaya, Lubov
2018-03-01
The article considers the issues of developing national standards for high-rise construction. The system of standards should provide industrial, operational, economic and terrorist safety of high-rise buildings and facilities. Modern standards of high-rise construction should set the rules for designing engineering systems of high-rise buildings, which will ensure the integrated security of buildings, increase their energy efficiency and reduce the consumption of resources in construction and operation.
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Sea Level Rise National Coastal Property Model
The impact of sea level rise on coastal properties depends critically on the human response to the threat, which in turn depends on several factors, including the immediacy of the risk, the magnitude of property value at risk, options for adapting to the threat and the cost of th...
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Comment [on “Sea level rise shown to drive coastal erosion”
Sallenger,, Asbury H.; Morton, Robert; Fletcher, Charles; Thieler, E. Robert; Howd, Peter
2000-01-01
In a recent article (Eos, Trans., AGU, February 8, 2000, p.55), Leatherman et al. [2000] state that they have confirmed an association between sea-level rise and coastal erosion. Applying their results to the New Jersey, Delaware, and Maryland coasts and using a projected sea-level rise, the authors predict that by 2050 the shoreline will recede 60 m, about two times the average beach width. However, Leatherman et al. [2000] have not convincingly quantified a relationship between sea-level rise and shoreline erosion.We do not agree with their rationale for subsetting their data, and they have not considered other explanations for a background erosion along the U.S. east coast. Furthermore, their future projections are not supported by their analyses.
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Crustal structure of Shatsky Rise from joint refraction and reflection seismic tomography
NASA Astrophysics Data System (ADS)
Korenaga, J.; Sager, W. W.
2011-12-01
Shatsky Rise in the western Pacific is one of a few gigantic oceanic plateaus in the world, with a surface area of ˜ 4.8 ± 105~km2 (about the same size as California). In contrast to other large oceanic plateaus formed during the Cretaceous Quite Period, Shatsky Rise formed during the frequent reversals of magnetic polarity, allowing its tectonic environment to be resolved in detail. It was formed at a rapidly spreading ridge-ridge-ridge triple junction, so the effect of lithospheric lid on magma migration is expected to be minimal, thereby facilitating the petrological interpretation of its seismic structure in terms of parental mantle processes. In the summer of 2010, a seismic refraction survey combined with multichannel seismic profiling was conducted across Shatsky Rise. Twenty eight ocean-bottom seismometers were deployed along two crossing perpendicular lines, and all of the instruments were recovered successfully, yielding a large volume of high-quality wide-angle refraction and reflection data, with the source-receiver distance often exceeding 200~km. In this contribution, we present the P-wave velocity structure of the Shatsky Rise crust, which is constructed by joint refraction and reflection travel time tomography, and also discuss its implications for the origin of Shatsky Rise.
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The Paradoxical Roles of Climate Stressors on Disturbance and Recovery of Coral Reef Ecosystems
NASA Astrophysics Data System (ADS)
Manfrino, C.; Foster, G.; Camp, E.
2013-05-01
The geographic isolation, absence of significant anthropogenic impacts, compressed spatial scale, and habitat diversity of Little Cayman combine to make it a natural laboratory for elucidating the dualistic impacts of various climatic events. These events both impart ecosystem disturbances and aid in the subsequent recovery of coral reef habitats. Within the isolated microcosm of Little Cayman the environmental factors commonly associated with coral stress, mortality, resilience and recovery hinted at by regional-scale observations can be more clearly observed. The primary thrust of this study is to reveal the under-pinning biophysical and hydrologic factors pertinent to reef resilience and to better understand the various roles played by climatic disturbances that have led to the rapid recovery of corals at Little Cayman following a spate of high temperature anomalies. Six closely-spaced high-temperature events were recorded in the Caribbean between the years of 1987 and 2009. Of these, only the 1998 global ENSO event, with well-documented levels of elevated SST, reduced cloud cover and surface water texture with concomittant increases in UV and irradiance and reduced water velocity, resulted in significant mortality at Little Cayman. Following this event, island-wide live coral cover decreased by 40%, from 26% to 14%. Annual monitoring of live coral cover following the 1998 ENSO event revealed no significant recovery of live coral cover until 2009, at which point there was a rapid rebound to pre-disturbance levels by 2011. Such a protracted step-change in coral recovery is indicative of one or more episodic events. The proposed scenario is that the numerous thermal stress events damaged the photo-system of the zooxanthellae, limiting the scope for growth and recovery as the metabolic budgets of corals were diverted to cellular repair. It is posited that the rapid cooling effect of frequent Tropical Storms and Hurricanes between 2002 - 2008, coupled with the
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Rising dynamics of a bubble confined in vertical cells with rectangular cross-sections
NASA Astrophysics Data System (ADS)
Murano, Mayuko; Okumura, Ko
2017-11-01
Recently, the drag friction acting on a fluid drop in confined space has been actively studied. Here, we investigate the rising velocity of a bubble in a vertical cell with a rectangular cross-section, both theoretically and experimentally, in which understanding of the drag force acting on the rising bubble is crucial. Although the drag force in such confined space could involve several regimes, we study a special case in which the bubble is long and the aspect-ratio of the rectangular cross-section of the cell is high. As a result, we found new scaling law for the rising velocity and the drag force, and confirmed the laws experimentally. Crossover to the rising dynamics in a Hele-Shaw cell will be also discussed.
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The Impact of Sea Level Rise on Florida's Everglades
NASA Astrophysics Data System (ADS)
Senarath, S. U.
2005-12-01
Global warming and the resulting melting of polar ice sheets could increase global sea levels significantly. Some studies have predicted mean sea level increases in the order of six inches to one foot in the next 25 to 50 years. This could have severe irreversible impacts on low-lying areas of Florida's Everglades. The key objective of this study is to evaluate the effects of a one foot sea level rise on Cape Sable Seaside Sparrow (CSSS) nesting areas within the Everglades National Park (ENP). A regional-scale hydrologic model is used to assess the sensitivities of this sea-level rise scenario. Florida's Everglades supports a unique ecosystem. At present, about 50 percent of this unique ecosystem has been lost due to urbanization and farming. Today, the water flow in the remnant Everglades is also regulated to meet a variety of competing environmental, water-supply and flood-control needs. A 30-year, eight billion dollar (1999 estimate) project has been initiated to improve Everglades' water flows. The expected benefits of this restoration project will be short-lived if the predicted sea level rise causes severe impacts on the environmentally sensitive areas of the Everglades. Florida's Everglades is home to many threatened and endangered species of wildlife. The Cape Sable Seaside Sparrow population in the ENP is one such species that is currently listed as endangered. Since these birds build their nests close to the ground surface (the base of the nest is approximately six inches from the ground surface), they are directly affected by any sea level induced ponding depth, frequency or duration change. Therefore, the CSSS population serves as a good indicator species for evaluating the negative impacts of sea level rise on the Everglades' ecosystem. The impact of sea level rise on the CSSS habitat is evaluated using the Regional Simulation Model (RSM) developed by the South Florida Water Management District. The RSM is an implicit, finite-volume, continuous
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The rise of angiosperm-dominated herbaceous floras: Insights from Ranunculaceae.
Wang, Wei; Lin, Li; Xiang, Xiao-Guo; Ortiz, Rosa Del C; Liu, Yang; Xiang, Kun-Li; Yu, Sheng-Xiang; Xing, Yao-Wu; Chen, Zhi-Duan
2016-06-02
The rise of angiosperms has been regarded as a trigger for the Cretaceous revolution of terrestrial ecosystems. However, the timeframe of the rise angiosperm-dominated herbaceous floras (ADHFs) is lacking. Here, we used the buttercup family (Ranunculaceae) as a proxy to provide insights into the rise of ADHFs. An integration of phylogenetic, molecular dating, ancestral state inferring, and diversification analytical methods was used to infer the early evolutionary history of Ranunculaceae. We found that Ranunculaceae became differentiated in forests between about 108-90 Ma. Diversification rates markedly elevated during the Campanian, mainly resulted from the rapid divergence of the non-forest lineages, but did not change across the Cretaceous-Paleogene boundary. Our data for Ranunculaceae indicate that forest-dwelling ADHFs may have appeared almost simultaneously with angiosperm-dominated forests during the mid-Cretaceous, whereas non-forest ADHFs arose later, by the end of the Cretaceous terrestrial revolution. Furthermore, ADHFs were relatively unaffected by the Cretaceous-Paleogene mass extinction.
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The rise of angiosperm-dominated herbaceous floras: Insights from Ranunculaceae
Wang, Wei; Lin, Li; Xiang, Xiao-Guo; Ortiz, Rosa del C.; Liu, Yang; Xiang, Kun-Li; Yu, Sheng-Xiang; Xing, Yao-Wu; Chen, Zhi-Duan
2016-01-01
The rise of angiosperms has been regarded as a trigger for the Cretaceous revolution of terrestrial ecosystems. However, the timeframe of the rise angiosperm-dominated herbaceous floras (ADHFs) is lacking. Here, we used the buttercup family (Ranunculaceae) as a proxy to provide insights into the rise of ADHFs. An integration of phylogenetic, molecular dating, ancestral state inferring, and diversification analytical methods was used to infer the early evolutionary history of Ranunculaceae. We found that Ranunculaceae became differentiated in forests between about 108–90 Ma. Diversification rates markedly elevated during the Campanian, mainly resulted from the rapid divergence of the non-forest lineages, but did not change across the Cretaceous-Paleogene boundary. Our data for Ranunculaceae indicate that forest-dwelling ADHFs may have appeared almost simultaneously with angiosperm-dominated forests during the mid-Cretaceous, whereas non-forest ADHFs arose later, by the end of the Cretaceous terrestrial revolution. Furthermore, ADHFs were relatively unaffected by the Cretaceous-Paleogene mass extinction. PMID:27251635
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Rising Tides: Faculty Expectations of Library Websites
ERIC Educational Resources Information Center
Nicol, Erica Carlson; O'English, Mark
2012-01-01
Looking at 2003-2009 LibQUAL+ responses at research-oriented universities in the United States, faculty library users report a significant and consistent rise in desires and expectations for library-provided online tools and websites, even as student user groups show declining or leveling expectations. While faculty, like students, also report…
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Consequences of sea level variability and sea level rise for Cuban territory
NASA Astrophysics Data System (ADS)
Hernández, M.; Martínez, C. A.; Marzo, O.
2015-03-01
The objective of the present paper was to determine a first approximation of coastal zone flooding by 2100, taking into account the more persistent processes of sea level variability and non-accelerated linear sea level rise estimation to assess the main impacts. The annual linear rate of mean sea level rise in the Cuban archipelago, obtained from the longest tide gauge records, has fluctuated between 0.005 cm/year at Casilda and 0.214 cm/year at Siboney. The main sea level rise effects for the Cuban coastal zone due to climate change and global warming are shown. Monthly and annual mean sea level anomalies, some of which are similar to or higher than the mean sea level rise estimated for halfway through the present century, reinforce the inland seawater penetration due to the semi-daily high tide. The combination of these different events will result in the loss of goods and services, and require expensive investments for adaption.
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A Bayesian network to predict vulnerability to sea-level rise: data report
Gutierrez, Benjamin T.; Plant, Nathaniel G.; Thieler, E. Robert
2011-01-01
During the 21st century, sea-level rise is projected to have a wide range of effects on coastal environments, development, and infrastructure. Consequently, there has been an increased focus on developing modeling or other analytical approaches to evaluate potential impacts to inform coastal management. This report provides the data that were used to develop and evaluate the performance of a Bayesian network designed to predict long-term shoreline change due to sea-level rise. The data include local rates of relative sea-level rise, wave height, tide range, geomorphic classification, coastal slope, and shoreline-change rate compiled as part of the U.S. Geological Survey Coastal Vulnerability Index for the U.S. Atlantic coast. In this project, the Bayesian network is used to define relationships among driving forces, geologic constraints, and coastal responses. Using this information, the Bayesian network is used to make probabilistic predictions of shoreline change in response to different future sea-level-rise scenarios.
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Coastal Louisiana in Crisis: Subsidence or Sea Level Rise?
NASA Astrophysics Data System (ADS)
González, Juan L.; Törnqvist, Torbjörn E.
2006-11-01
The drowning of wetlands and barrier islands in coastal Louisiana has become a widely publicized environmental catastrophe in the wake of hurricanes Katrina and Rita in 2005. The devastation caused by these storms has reenergized the debate about restoring the natural coastal-defense system and building higher and sturdier levees, in anticipation of future storms. Understanding the contributions of land subsidence and eustatic (global) sea level rise to Louisiana's wetland loss is crucial to the success of any plan designed to protect coastal communities. It is argued here that accelerated sea level rise in the future may pose a larger threat than subsidence for considerable portions of coastal Louisiana.
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Humidity Distributions in Multilayered Walls of High-rise Buildings
NASA Astrophysics Data System (ADS)
Gamayunova, Olga; Musorina, Tatiana; Ishkov, Alexander
2018-03-01
The limitation of free territories in large cities is the main reason for the active development of high-rise construction. Given the large-scale projects of high-rise buildings in recent years in Russia and abroad and their huge energy consumption, one of the fundamental principles in the design and reconstruction is the use of energy-efficient technologies. The main heat loss in buildings occurs through enclosing structures. However, not always the heat-resistant wall will be energy-efficient and dry at the same time (perhaps waterlogging). Temperature and humidity distributions in multilayer walls were studied in the paper, and the interrelation of other thermophysical characteristics was analyzed.
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Insights into Rift Initiation, Evolution, and Failure from North America's Midcontinent Rift
NASA Astrophysics Data System (ADS)
Stein, C. A.; Stein, S.; Elling, R. P.; Keller, G. R.; Kley, J.; Wysession, M. E.
2017-12-01
Recent studies of the Midcontinent Rift (MCR) near Lake Superior give insights into how some rifts start, evolve, and fail because the rift-filling volcanic and sedimentary rocks are exposed at the surface and well imaged by deep seismic reflection and gravity data. The MCR was traditionally considered to have formed by midplate extension and volcanism 1.1 Ga that ended due to compression from the Grenville orogeny, the 1.3 - 0.98 Ga assembly of Amazonia (Precambrian northeast South America), Laurentia (Precambrian North America), and other continents into the supercontinent of Rodinia. We find that a more plausible scenario is that the MCR formed as part of the rifting of Amazonia from Laurentia and became inactive once seafloor spreading was established. A cusp in Laurentia's apparent polar wander path just before the onset of MCR volcanism likely reflects the rifting. Such cusps have been observed elsewhere when continents separate and a new ocean forms between the two fragments. New analyses also find that the MCR's failure did not result from Grenville compression. This view is consistent with the observation that many intracontinental rifts form and fail as part of plate boundary reorganizations. Present-day continental extension in the East African Rift and seafloor spreading in the Red Sea and Gulf of Aden form a classic three-arm rift geometry as Africa splits into Nubia, Somalia, and Arabia. The West Central African Rift system formed during the Mesozoic breakup of Africa and South America and became inactive once full seafloor spreading was established on the Mid-Atlantic Ridge. An important feature of the MCR is that it is has aspects both of a continental rift - a segmented linear depression filled with sedimentary and igneous rocks - and a large igneous province (LIP). We view it as a LIP deposited in crust weakened by rifting, and thus first a rift and then a LIP. The MCR exhibits many key features of volcanic passive margins: seaward dipping
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GRACE Detected Rise of Groundwater in the Sahelian Niger River Basin
NASA Astrophysics Data System (ADS)
Werth, S.; White, D.; Bliss, D. W.
2017-12-01
West African regions along the Niger River experience climate and land cover changes that affect hydrological processes and therewith the distribution of fresh water resources (WR). This study provides an investigation of long-term changes in terrestrial water storages (TWS) of the Niger River basin and its subregions by analyzing a decade of satellite gravity data from the Gravity Recovery and Climate Experiment (GRACE) mission. The location of large trends in TWS maps of differently processed GRACE solutions points to rising groundwater stocks. Soil moisture data from a global land surface model allow separating the effect of significantly increasing amount of WR from that of TWS variations. Surface water variations from a global water storage model validated with observations from altimetry data were applied to estimate the groundwater component in WR. For the whole Niger, a rise in groundwater stocks is estimated to be 93 ± 61 km3 between January 2003 and December 2013. A careful analysis of uncertainties in all data sets supports the significance of the groundwater rise. Our results confirm previous observations of rising water tables, indicating that effects of land cover changes on groundwater storage are relevant on basin scales. Areas with rising water storage are stocking a comfortable backup to mitigate possible future droughts and to deliver water to remote areas. This has implications for Niger water management strategies. Increasing groundwater recharges may be accompanied by reduction in water quality. This study helps to inform authority's decision to mitigate its negative impacts on local communities.
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Can sea level rise cause large submarine landslides on continental slopes?
NASA Astrophysics Data System (ADS)
Urlaub, Morelia
2014-05-01
Submarine landslides are one of the volumetrically most important sediment transport processes at continental margins. Moreover, these landslides are a major geohazard as they can cause damaging tsunamis and destroy seabed infrastructure. Due to their inaccessibility our understanding of what causes these landslides is limited and based on hypotheses that are difficult to test. Some of the largest submarine landslides, such as the Storegga Slide off Norway, occurred during times of eustatic sea level rise. It has been suggested that this global sea level rise was implicated in triggering of the landslides by causing an increase in excess pore pressure in the subseafloor. However, in a homogeneous slope a change in the thickness of the overlying water mass is not expected to affect its stability, as only the hydrostatic pressure component will change, whereas pore pressures in excess of hydrostatic will remain unaltered. Whether sufficiently rapid sea level rise, aided by rather impermeable sediment and complex layering, could cause excess pore pressures that may destabilise a continental slope is more difficult to answer and has not yet been tested. I use Finite Element Modelling to explore and quantify the direct effect of changes in the thickness of the overlying water mass on the stability of a generic sediment column with different stratigraphic conditions and hydro-mechanical properties. The results show that the direct effect of sea level rise on continental slope stability is minimal. Nevertheless, sea level rise may foster other processes, such as lithospheric stress changes resulting in increased seismicity, that could potentially cause large submarine landslides on continental slopes.
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In vitro pulp chamber temperature rise from irradiation and exotherm of flowable composites.
Baroudi, Kusai; Silikas, Nick; Watts, David C
2009-01-01
The aim of this study was to investigate the pulpal temperature rise induced during the polymerization of flowable and non-flowable composites using light-emitting diode (LED) and halogen (quartz-tungsten-halogen) light-curing units (LCUs). Five flowable and three non-flowable composites were examined. Pulpal temperature changes were recorded over 10 min in a sample primary tooth by a thermocouple. A conventional quartz-tungsten-halogen source and two LEDs, one of which was programmable, were used for light curing the resin composites. Three repetitions per material were made for each LCU. There was a wide range of temperature rises among the materials (P < 0.05). Temperature rises ranged between 1.3 degrees C for Filtek Supreme irradiated by low-power LED and 4.5 degrees C for Grandio Flow irradiated by high-power LED. The highest temperature rises were observed with both the LED high-power and soft-start LCUs. The time to reach the exothermic peak varied significantly between the materials (P < 0.05). Pulpal temperature rise is related to both the radiant energy output from LCUs and the polymerization exotherm of resin composites. A greater potential risk for heat-induced pulp damage might be associated with high-power LED sources. Flowable composites exhibited higher temperature rises than non-flowable materials, because of higher resin contents.
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Flooded! An Investigation of Sea-Level Rise in a Changing Climate
ERIC Educational Resources Information Center
Gillette, Brandon; Hamilton, Cheri
2011-01-01
Explore how melting ice sheets affect global sea levels. Sea-level rise (SLR) is a rise in the water level of the Earth's oceans. There are two major kinds of ice in the polar regions: sea ice and land ice. Land ice contributes to SLR and sea ice does not. This article explores the characteristics of sea ice and land ice and provides some hands-on…
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NASA Astrophysics Data System (ADS)
Rose, Michael A.
2007-08-01
Copernicus Rising began as a historical biography when it was first conceived, but as the writing progressed it quickly became a rather absurd play that took historical research and twisted it through the lens of my own wit, philosophy and personal affection for the characters. When working with historical figures--characters who existed in a very tangible way in our own history--the playwriting process opens a dialogue between different points in time and space. The difficulty lies in finding a unique and clear voice amongst the discordant personalities involved in this time and space overlap, both in the writing and production processes, in order to get to the heart of what the play is really all about. This thesis follows the journey of the play from its historical roots through the creation of an absurd journey both insides and outside time, space and the human mind. The first part of the thesis explains the beginnings of the concept and outlines much of the research and development that went into the play. The next part outlines the process of production and integrating the world on paper with that of moving bodies on stage. In the final part, post-production discussions and audience feedback sessions shape the play into the draft included in this thesis.
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Acceleration of Sea Level Rise Over Malaysian Seas from Satellite Altimeter
NASA Astrophysics Data System (ADS)
Hamid, A. I. A.; Din, A. H. M.; Khalid, N. F.; Omar, K. M.
2016-09-01
Sea level rise becomes our concern nowadays as a result of variously contribution of climate change that cause by the anthropogenic effects. Global sea levels have been rising through the past century and are projected to rise at an accelerated rate throughout the 21st century. Due to this change, sea level is now constantly rising and eventually will threaten many low-lying and unprotected coastal areas in many ways. This paper is proposing a significant effort to quantify the sea level trend over Malaysian seas based on the combination of multi-mission satellite altimeters over a period of 23 years. Eight altimeter missions are used to derive the absolute sea level from Radar Altimeter Database System (RADS). Data verification is then carried out to verify the satellite derived sea level rise data with tidal data. Eight selected tide gauge stations from Peninsular Malaysia, Sabah and Sarawak are chosen for this data verification. The pattern and correlation of both measurements of sea level anomalies (SLA) are evaluated over the same period in each area in order to produce comparable results. Afterwards, the time series of the sea level trend is quantified using robust fit regression analysis. The findings clearly show that the absolute sea level trend is rising and varying over the Malaysian seas with the rate of sea level varies and gradually increase from east to west of Malaysia. Highly confident and correlation level of the 23 years measurement data with an astonishing root mean square difference permits the absolute sea level trend of the Malaysian seas has raised at the rate 3.14 ± 0.12 mm yr-1 to 4.81 ± 0.15 mm yr-1 for the chosen sub-areas, with an overall mean of 4.09 ± 0.12 mm yr-1. This study hopefully offers a beneficial sea level information to be applied in a wide range of related environmental and climatology issue such as flood and global warming.
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Temperature rises during application of Er:YAG laser under different primary dentin thicknesses.
Hubbezoglu, Ihsan; Unal, Murat; Zan, Recai; Hurmuzlu, Feridun
2013-05-01
The present study investigated the effects of the Er:YAG laser's different pulse repetition rates on temperature rise under various primary dentin thicknesses. The Er:YAG laser can be used for restorative approaches in clinics and is used to treat dental caries. There are some reports that explain the temperature rise effect of the Er:YAG laser. Recently, the Er:YAG laser has been found to play an important role in temperature rises during the application on dentin. Caries-free primary mandibular molars were prepared to obtain dentin discs with 0.5, 1, 1.5, and 2 mm thicknesses (n=10). These discs were placed between the Teflon mold cylinders of a temperature test apparatus. We preferred three pulse repetition rates of 10, 15, and 20 Hz with an energy density of 12.7 J/cm2 and a 230 μs pulse duration. All dentin discs were irradiated for 30 sec by the Er:YAG laser. Temperature rises were recorded using an L-type thermocouple and universal data loggers/scanners (E-680, Elimko Co., Turkey). Data were analyzed by two-way ANOVA and Tukey tests. Whereas the lowest temperature rise (0.44±0.09 °C) was measured from a 10 Hz pulse repetition rate at a dentin thickness of 2 mm, the highest temperature rise (3.86±0.43 °C) was measured from a 20 Hz pulse repetition rate at a 0.5 mm dentin thickness. Temperature rise did not reach critical value for pulpal injury in any primary dentin thicknesses irradiated by a high repetition rate of the Er:YAG laser.
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77 FR 26280 - Patient Safety Organizations: Voluntary Relinquishment From CareRise LLC
Federal Register 2010, 2011, 2012, 2013, 2014
2012-05-03
... Organizations: Voluntary Relinquishment From CareRise LLC AGENCY: Agency for Healthcare Research and Quality... relinquishment from CareRise LLC of its status as a Patient Safety Organization (PSO). The Patient Safety and... safety and the quality of health care delivery. HHS issued the Patient Safety and Quality Improvement...
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NASA Astrophysics Data System (ADS)
Zaychenko, Irina; Borremans, Alexandra; Gutman, Svetlana
2018-03-01
The article describes the concept and types of administrative barriers encountered in various areas of the enterprise. The particularities of the Russian high-rise construction industry are described and a comparative analysis of administrative barriers in this sector is performed. The main stages and administrative procedures when the developers implement investment and construction projects in the field of high-rise construction are determined. The regulatory and legal framework for the implementation of investment and project activities in the high-rise construction industry has been studied and conclusions have been drawn on its low level of precision in the issue of the formation of competitive and efficient high-rise construction markets. The average number of administrative procedures for the implementation of the investment and construction project in the field of high-rise construction is determined. The factors preventing the reduction of administrative barriers in the high-rise construction industry are revealed.
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Ceramic thermal barrier coating for rapid thermal cycling applications
Scharman, Alan J.; Yonushonis, Thomas M.
1994-01-01
A thermal barrier coating for metal articles subjected to rapid thermal cycling includes a metallic bond coat deposited on the metal article, at least one MCrAlY/ceramic layer deposited on the bond coat, and a ceramic top layer deposited on the MCrAlY/ceramic layer. The M in the MCrAlY material is Fe, Ni, Co, or a mixture of Ni and Co. The ceramic in the MCrAlY/ceramic layer is mullite or Al.sub.2 O.sub.3. The ceramic top layer includes a ceramic with a coefficient of thermal expansion less than about 5.4.times.10.sup.-6 .degree.C.sup.-1 and a thermal conductivity between about 1 J sec.sup.-1 m.sup.-1 .degree.C.sup.-1 and about 1.7 J sec.sup.-1 m.sup.-1 .degree.C.sup.-1.
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Potential effects of sea-level rise on coastal wetlands in southeastern Louisiana
Glick, Patty; Clough, Jonathan; Polaczyk, Amy; Couvillion, Brady R.; Nunley, Brad
2013-01-01
Coastal Louisiana wetlands contain about 37% of the estuarine herbaceous marshes in the conterminous United States. The long-term stability of coastal wetlands is often a function of a wetland's ability to maintain elevation equilibrium with mean sea level through processes such as primary production and sediment accretion. However, Louisiana has sustained more coastal wetland loss than all other states in the continental United States combined due to a combination of natural and anthropogenic factors, including sea-level rise. This study investigates the potential impact of current and accelerating sea-level rise rates on key coastal wetland habitats in southeastern Louisiana using the Sea Level Affecting Marshes Model (SLAMM). Model calibration was conducted using a 1956–2007 observation period and hindcasting results predicted 35% versus observed 39% total marsh loss. Multiple sea-level-rise scenarios were then simulated for the period of 2007–2100. Results indicate a range of potential wetland losses by 2100, from an additional 2,188.97 km2 (218,897 ha, 9% of the 2007 wetland area) under the lowest sea-level-rise scenario (0.34 m), to a potential loss of 5,875.27 km2 (587,527 ha, 24% of the 2007 wetland area) in the highest sea-level-rise scenario (1.9 m). Model results suggest that one area of particular concern is the potential vulnerability of the region's baldcypress-water tupelo (Taxodium distichum-Nyssa aquatica) swamp habitat, much of which is projected to become permanently flooded (affecting regeneration) under all modeled scenarios for sea-level rise. These findings will aid in the development of ecosystem management plans that support the processes and conditions that result in sustainable coastal ecosystems.
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The Rise of the Digital Public Library
ERIC Educational Resources Information Center
McKendrick, Joseph
2012-01-01
There is a growing shift to digital offerings among public libraries. Libraries increasingly are fulfilling roles as technology hubs for their communities, with high demand for technology and career development training resources. Ebooks and other digital materials are on the rise, while print is being scaled back. More libraries are turning to…
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The DISAM Journal of International Security Assistance Management. Volume 26, Number 1, Fall 2003
2003-01-01
contribution to international peace and stability. Current Members of the Hall of Fame General Lojas Fodor, Commander, Hungarian Defense Forces and Chief of...Belize Bermuda Bolivia Brazil British Virgin Islands Cayman Islands Chile Colombia Costa Rica Cuba Dominica Dominican Republic Ecuador El
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The contribution of sea-level rise to flooding in large river catchments
NASA Astrophysics Data System (ADS)
Thiele-Eich, I.; Hopson, T. M.; Gilleland, E.; Lamarque, J.; Hu, A.; Simmer, C.
2012-12-01
Climate change is expected to both impact sea level rise as well as flooding. Our study focuses on the combined effect of climate change on upper catchment precipitation as well as on sea-level rise at the river mouths and the impact this will have on river flooding both at the coast and further upstream. We concentrate on the eight catchments of the Amazonas, Congo, Orinoco, Ganges/Brahmaputra/Meghna, Mississippi, St. Lawrence, Danube and Niger rivers. To assess the impact of climate change, upper catchment precipitation as well as monthly mean thermosteric sea-level rise at the river mouth outflow are taken from the four CCSM4 1° 20th Century ensemble members as well as from six CCSM4 1° ensemble members for the RCP scenarios RCP8.5, 6.0, 4.5 and 2.6. Continuous daily time series for average catchment precipitation and discharge are available for each of the catchments. To arrive at a future discharge time series, we used these observations to develop a simple statistical hydrological model which can be applied to the modelled future upper catchment precipitation values. The analysis of this surrogate discharge time series alone already yields significant changes in flood return levels as well as flood duration. Using the geometry of the river channel, the backwater effect of sea-level rise is incorporated in our analysis of both flood frequencies and magnitudes by calculating the effective additional discharge due to the increase in water level at the river mouth outflow, as well as its tapering impact upstream. By combining these effects, our results focus on the merged impact of changes in extreme precipitation with increases in river height due to sea-level rise at the river mouths. Judging from our preliminary results, the increase in effective discharge due to sea-level rise cannot be neglected when discussing late 21st century flooding in the respective river basins. In particular, we find that especially in countries with low elevation gradient, flood
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Cadol, Daniel; Elmore, Andrew J.; Guinn, Steven M.; Engelhardt, Katharina A. M.; Sanders, Geoffrey
2016-01-01
Tidal habitats host a diversity of species and provide hydrological services such as shoreline protection and nutrient attenuation. Accretion of sediment and biomass enables tidal marshes and swamps to grow vertically, providing a degree of resilience to rising sea levels. Even if accelerating sea level rise overcomes this vertical resilience, tidal habitats have the potential to migrate inland as they continue to occupy land that falls within the new tide range elevations. The existence of developed land inland of tidal habitats, however, may prevent this migration as efforts are often made to dyke and protect developments. To test the importance of inland migration to maintaining tidal habitat abundance under a range of potential rates of sea level rise, we developed a spatially explicit elevation tracking and habitat switching model, dubbed the Marsh Accretion and Inundation Model (MAIM), which incorporates elevation-dependent net land surface elevation gain functions. We applied the model to the metropolitan Washington, DC region, finding that the abundance of small National Park Service units and other public open space along the tidal Potomac River system provides a refuge to which tidal habitats may retreat to maintain total habitat area even under moderate sea level rise scenarios (0.7 m and 1.1 m rise by 2100). Under a severe sea level rise scenario associated with ice sheet collapse (1.7 m by 2100) habitat area is maintained only if no development is protected from rising water. If all existing development is protected, then 5%, 10%, and 40% of the total tidal habitat area is lost by 2100 for the three sea level rise scenarios tested. PMID:27788209
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Cadol, Daniel; Elmore, Andrew J; Guinn, Steven M; Engelhardt, Katharina A M; Sanders, Geoffrey
2016-01-01
Tidal habitats host a diversity of species and provide hydrological services such as shoreline protection and nutrient attenuation. Accretion of sediment and biomass enables tidal marshes and swamps to grow vertically, providing a degree of resilience to rising sea levels. Even if accelerating sea level rise overcomes this vertical resilience, tidal habitats have the potential to migrate inland as they continue to occupy land that falls within the new tide range elevations. The existence of developed land inland of tidal habitats, however, may prevent this migration as efforts are often made to dyke and protect developments. To test the importance of inland migration to maintaining tidal habitat abundance under a range of potential rates of sea level rise, we developed a spatially explicit elevation tracking and habitat switching model, dubbed the Marsh Accretion and Inundation Model (MAIM), which incorporates elevation-dependent net land surface elevation gain functions. We applied the model to the metropolitan Washington, DC region, finding that the abundance of small National Park Service units and other public open space along the tidal Potomac River system provides a refuge to which tidal habitats may retreat to maintain total habitat area even under moderate sea level rise scenarios (0.7 m and 1.1 m rise by 2100). Under a severe sea level rise scenario associated with ice sheet collapse (1.7 m by 2100) habitat area is maintained only if no development is protected from rising water. If all existing development is protected, then 5%, 10%, and 40% of the total tidal habitat area is lost by 2100 for the three sea level rise scenarios tested.
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45 CFR 77.3 - Conditions that may give rise to remedial actions.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 45 Public Welfare 1 2011-10-01 2011-10-01 false Conditions that may give rise to remedial actions. 77.3 Section 77.3 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION REMEDIAL ACTIONS APPLICABLE TO LETTER OF CREDIT ADMINISTRATION § 77.3 Conditions that may give rise to...
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45 CFR 77.3 - Conditions that may give rise to remedial actions.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 45 Public Welfare 1 2010-10-01 2010-10-01 false Conditions that may give rise to remedial actions. 77.3 Section 77.3 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION REMEDIAL ACTIONS APPLICABLE TO LETTER OF CREDIT ADMINISTRATION § 77.3 Conditions that may give rise to...
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Development of high-rise buildings: digitalization of life cycle management
NASA Astrophysics Data System (ADS)
Gusakova, Elena
2018-03-01
The analysis of the accumulated long-term experience in the construction and operation of high-rise buildings reveals not only the engineering specificity of such projects, but also systemic problems in the field of project management. Most of the project decisions are made by the developer and the investor in the early stages of the life cycle - from the acquisition of the site to the start of operation, so most of the participants in the construction and operation of the high-rise building are far from the strategic life-cycle management of the project. The solution of these tasks due to the informatization of management has largely exhausted its efficiency resource. This is due to the fact that the applied IT-systems automated traditional "inherited" processes and management structures, and, in addition, they were focused on informatization of the activities of the construction company, rather than the construction project. Therefore, in the development of high-rise buildings, the tasks of researching approaches and methods for managing the full life cycle of projects that will improve their competitiveness become topical. For this purpose, the article substantiates the most promising approaches and methods of informational modeling of high-rise construction as a basis for managing the full life cycle of this project. Reengineering of information interaction schemes for project participants is considered; formation of a unified digital environment for the life cycle of the project; the development of systems for integrating data management and project management.
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Committed sea-level rise under the Paris Agreement and the legacy of delayed mitigation action.
Mengel, Matthias; Nauels, Alexander; Rogelj, Joeri; Schleussner, Carl-Friedrich
2018-02-20
Sea-level rise is a major consequence of climate change that will continue long after emissions of greenhouse gases have stopped. The 2015 Paris Agreement aims at reducing climate-related risks by reducing greenhouse gas emissions to net zero and limiting global-mean temperature increase. Here we quantify the effect of these constraints on global sea-level rise until 2300, including Antarctic ice-sheet instabilities. We estimate median sea-level rise between 0.7 and 1.2 m, if net-zero greenhouse gas emissions are sustained until 2300, varying with the pathway of emissions during this century. Temperature stabilization below 2 °C is insufficient to hold median sea-level rise until 2300 below 1.5 m. We find that each 5-year delay in near-term peaking of CO 2 emissions increases median year 2300 sea-level rise estimates by ca. 0.2 m, and extreme sea-level rise estimates at the 95th percentile by up to 1 m. Our results underline the importance of near-term mitigation action for limiting long-term sea-level rise risks.
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High-pressure hydrogen respiration in hydrothermal vent samples from the deep biosphere
NASA Astrophysics Data System (ADS)
Morgan-Smith, D.; Schrenk, M. O.
2013-12-01
Cultivation of organisms from the deep biosphere has met with many challenges, chief among them the ability to replicate this extreme environment in a laboratory setting. The maintenance of in situ pressure levels, carbon sources, and gas concentrations are important, intertwined factors which may all affect the growth of subsurface microorganisms. Hydrogen in particular is of great importance in hydrothermal systems, but in situ hydrogen concentrations are largely disregarded in attempts to culture from these sites. Using modified Hungate-type culture tubes (Bowles et al. 2011) within pressure-retaining vessels, which allow for the dissolution of higher concentrations of gas than is possible with other culturing methods, we have incubated hydrothermal chimney and hydrothermally-altered rock samples from the Lost City and Mid-Cayman Rise hydrothermal vent fields. Hydrogen concentrations up to 15 mmol/kg have been reported from Lost City (Kelley et al. 2005), but data are not yet available from the recently-discovered Mid-Cayman site, and the elevated concentration of 30 mmol/kg is being used in all incubations. We are using a variety of media types to enrich for various metabolic pathways including iron and sulfur reduction under anoxic or microaerophilic conditions. Incubations are being carried out at atmospheric (0.1 MPa), in situ (9, 23, or 50 MPa, depending on site), and elevated (50 MPa) pressure levels. Microbial cell concentrations, taxonomic diversity, and metabolic activities are being monitored during the course of these experiments. These experiments will provide insight into the relationships between microbial activities, pressure, and gas concentrations typical of deep biosphere environments. Results will inform further culturing studies from both fresh and archived samples. References cited: Bowles, M.W., Samarkin, V.A., Joye, S.B. 2011. Improved measurement of microbial activity in deep-sea sediments at in situ pressure and methane concentration
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High-rise housing as a factor of the increase in Investment attractiveness of the city
NASA Astrophysics Data System (ADS)
Mottaeva, Angela; Zheltenkov, Alexander
2018-03-01
That is obviously for experts, irrespective of status or quality, high-rise housing is here to stay. No country is in a position to ignore or discard this conspicuous legacy of the post-war and mass housing period. Nevertheless, high-rise residential buildings are still less widespread, than offices. According to the author, there are certain problems and reasons for limitation of high-rise construction in the housing sector. The author summarizes successful experience of high-rise housing construction in the world and considers some social-and-economic prerequisites of its development in the modern city. These concrete examples, given in article, prove that the existing problems are being solved. The most effective option of construction is the combination of inhabited and commercial chambers in the high-rise building and also the creation of specific infrastructure. In that case housing high-rise estates will promote the increase in investment attractiveness and investment activity in the district and in the city as whole.
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Rising Political Consciousness: Transformational Learning in Malaysia.
ERIC Educational Resources Information Center
Kamis, Mazalan; Muhamad, Mazanah
As part of a larger study (not discussed) ten educated Malaysian citizens were interviewed to find whether their rising political consciousness, over a ten year period (1988-1999), indicated that their transformation was influenced by their culture. The subjects were between 35-45 years old, married, with an average of four children. All were…
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Using time lapse cameras to monitor shoreline changes due to sea level rise.
DOT National Transportation Integrated Search
2017-01-01
Shoreline habitats and infrastructure are currently being affected by sea level rise (SLR) and as : global temperatures continue to rise, will continue to get worse for millennia. Governments : and individuals decisions to adapt to SLR could ha...
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Collective space of high-rise housing complex
NASA Astrophysics Data System (ADS)
Bakaeva, Tatyana
2018-03-01
The article considers the problems of support of citizens a comfortable living environment in the conditions of the limited territory of the megalopolis, the typological principles of formation of space-planning structure high-rise residence complexes with public space. The collective space for residents of high-rise housing estates on the example of international experience of design and construction is in detail considered. The collective space and the area of the standard apartment are analysed on comfort classes: a social - complex Pinnacle @ Duxton, a business - Monde Condos and an elite - Hamilton Scotts. Interdependence the area of the standard flat and the total area of housing collective space, in addiction on the comfort level, is revealed. In the conditions of high-density urban development, the collective space allows to form the comfortable environment for accommodation. The recommendations for achievement of integrity and improvement of quality of the city environment are made. The convenient collective space makes a contribution to civil policy, it creates the socializing sense of interaction of residents, coagulates social effect.
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Rising synchrony controls western North American ecosystems.
Black, Bryan A; van der Sleen, Peter; Di Lorenzo, Emanuele; Griffin, Daniel; Sydeman, William J; Dunham, Jason B; Rykaczewski, Ryan R; García-Reyes, Marisol; Safeeq, Mohammad; Arismendi, Ivan; Bograd, Steven J
2018-06-01
Along the western margin of North America, the winter expression of the North Pacific High (NPH) strongly influences interannual variability in coastal upwelling, storm track position, precipitation, and river discharge. Coherence among these factors induces covariance among physical and biological processes across adjacent marine and terrestrial ecosystems. Here, we show that over the past century the degree and spatial extent of this covariance (synchrony) has substantially increased, and is coincident with rising variance in the winter NPH. Furthermore, centuries-long blue oak (Quercus douglasii) growth chronologies sensitive to the winter NPH provide robust evidence that modern levels of synchrony are among the highest observed in the context of the last 250 years. These trends may ultimately be linked to changing impacts of the El Niño Southern Oscillation on midlatitude ecosystems of North America. Such a rise in synchrony may destabilize ecosystems, expose populations to higher risks of extinction, and is thus a concern given the broad biological relevance of winter climate to biological systems. © 2018 John Wiley & Sons Ltd.
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Methods for detection of methyl-CpG dinucleotides
Dunn, John J
2013-11-26
The invention provides methods for enriching methyl-CpG sequences from a DNA sample. The method makes use of conversion of cytosine residues to uracil under conditions in which methyl-cytosine residues are preserved. Additional methods of the invention enable to preservation of the context of me-CpG dinucleotides. The invention also provides a recombinant, full length and substantially pure McrA protein (rMcrA) for binding and isolation of DNA fragments containing the sequence 5'-C.sup.MeCpGG-3'. Methods for making and using the rMcrA protein, and derivatives thereof are provided.
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Methods for detection of methyl-CpG dinucleotides
Dunn, John J.
2013-01-29
The invention provides methods for enriching methyl-CpG sequences from a DNA sample. The method makes use of conversion of cytosine residues to uracil under conditions in which methyl-cytosine residues are preserved. Additional methods of the invention enable to preservation of the context of me-CpG dinucleotides. The invention also provides a recombinant, full length and substantially pure McrA protein (rMcrA) for binding and isolation of DNA fragments containing the sequence 5'-C.sup.MeCpGG-3'. Methods for making and using the rMcrA protein, and derivatives thereof are provided.
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Methods for detection of methyl-CpG dinucleotides
Dunn, John J.
2012-09-11
The invention provides methods for enriching methyl-CpG sequences from a DNA sample. The method makes use of conversion of cytosine residues to uracil under conditions in which methyl-cytosine residues are preserved. Additional methods of the invention enable to preservation of the context of me-CpG dinucleotides. The invention also provides a recombinant, full length and substantially pure McrA protein (rMcrA) for binding and isolation of DNA fragments containing the sequence 5'-C.sup.MeCpGG-3'. Methods for making and using the rMcrA protein, and derivatives thereof are provided.
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Method for applying a diffusion barrier interlayer for high temperature components
Wei, Ronghua; Cheruvu, Narayana S.
2016-03-08
A coated substrate and a method of forming a diffusion barrier coating system between a substrate and a MCrAl coating, including a diffusion barrier coating deposited onto at least a portion of a substrate surface, wherein the diffusion barrier coating comprises a nitride, oxide or carbide of one or more transition metals and/or metalloids and a MCrAl coating, wherein M includes a transition metal or a metalloid, deposited on at least a portion of the diffusion barrier coating, wherein the diffusion barrier coating restricts the inward diffusion of aluminum of the MCrAl coating into the substrate.
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Chen, Li-Wu; Stoner, Julie; Makhanu, Catherine; Minikus, Kathy; Mueller, Keith J
2004-05-01
Very few studies have thoroughly examined the discrepancies between the financial information in the Medicare Cost Report (MCR) and that in the audited hospital financial statement (FS). Furthermore, this type of study has never been conducted for rural hospitals. In this policy brief, we present the findings from our study, which used statistical methods to examine the agreement between the MCR and the FS of a series of financial measures in rural hospitals. The results are expected to inform policy makers of the limitation inherent in using MCR data as the single source of data to examine the financial performance of rural hospitals.
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Production and perception of contrast: The case of the rise-fall contour in German
Kügler, Frank; Gollrad, Anja
2015-01-01
This study investigates the phonetics of German nuclear rise-fall contours in relation to contexts that trigger either a contrastive or a non-contrastive interpretation in the answer. A rise-fall contour can be conceived of a tonal sequence of L-H-L. A production study elicited target sentences in contrastive and non-contrastive contexts. The majority of cases realized showed a nuclear rise-fall contour. The acoustic analysis of these contours revealed a significant effect of contrastiveness on the height/alignment of the accent peak as a function of focus context. On the other hand, the height/alignment of the low turning point at the beginning of the rise did not show an effect of contrastiveness. In a series of semantic congruency perception tests participants judged the congruency of congruent and incongruent context-stimulus pairs based on three different sets of stimuli: (i) original data, (ii) manipulation of accent peak, and (iii) manipulation of the leading low. Listeners distinguished nuclear rise-fall contours as a function of focus context (Experiment 1 and 2), however not based on manipulations of the leading low (Experiment 3). The results suggest that the alignment and scaling of the accentual peak are sufficient to license a contrastive interpretation of a nuclear rise-fall contour, leaving the rising part as a phonetic onglide, or as a low tone that does not interact with the contrastivity of the context. PMID:26388795