WorldWideScience

Sample records for central great barrier

  1. The effects of river run-off on water clarity across the central Great Barrier Reef.

    Science.gov (United States)

    Fabricius, K E; Logan, M; Weeks, S; Brodie, J

    2014-07-15

    Changes in water clarity across the shallow continental shelf of the central Great Barrier Reef were investigated from ten years of daily river load, oceanographic and MODIS-Aqua data. Mean photic depth (i.e., the depth of 10% of surface irradiance) was related to river loads after statistical removal of wave and tidal effects. Across the ∼25,000 km(2) area, photic depth was strongly related to river freshwater and phosphorus loads (R(2)=0.65 and 0.51, respectively). In the six wetter years, photic depth was reduced by 19.8% and below water quality guidelines for 156 days, compared to 9 days in the drier years. After onset of the seasonal river floods, photic depth was reduced for on average 6-8 months, gradually returning to clearer baseline values. Relationships were strongest inshore and midshelf (∼12-80 km from the coast), and weaker near the chronically turbid coast. The data show that reductions in river loads would measurably improve shelf water clarity, with significant ecosystem health benefits. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

  2. Temporal and taxonomic contrasts in coral growth at Davies Reef, central Great Barrier Reef, Australia

    Science.gov (United States)

    Anderson, Kristen D.; Cantin, Neal E.; Heron, Scott F.; Lough, Janice M.; Pratchett, Morgan S.

    2018-06-01

    Demographic processes, such as growth, can have an important influence on the population and community structure of reef-building corals. Importantly, ongoing changes in environmental conditions (e.g. ocean warming) are expected to affect coral growth, contributing to changes in the structure of coral populations and communities. This study quantified contemporary growth rates (linear extension and calcification) for the staghorn coral, Acropora muricata, at Davies Reef, central Great Barrier Reef, Australia. Growth rates were measured at three different depths (5, 10, and 15 m) over 2 yr (2012-2014) assessing both seasonal and inter-annual variability. Results of this study were compared to equivalent measurements made in 1980-1982 at the same location. To assist in understanding inter-annual variability in coral growth, we also examined annual growth bands from massive Porites providing continuous growth and records of flooding history for Davies Reef over the period 1979-2012. Linear extension rates of A. muricata were substantially (11-62%) lower in 2012-2014 compared to 1980-1982, especially at 10 and 15 m depths. These declines in growth coincide with a + 0.14 °C change in annual mean temperature. For massive Porites, however, calcification rates were highly variable among years and there was no discernible long-term change in growth despite sustained increases in temperature of 0.064 °C per decade. Apparent differences in the growth rates of Acropora between 1980-1982 and 2012-2014 may reflect inter-annual variation in coral growth (as seen for massive Porites), though it is known branching Acropora is much more sensitive to changing environmental conditions than massive corals. There are persistent issues in assessing the sensitivities of branching corals to environmental change due to limited capacity for retrospective analyses of growth, but given their disproportionate contribution to habitat complexity and reef structure, it is critical to ascertain

  3. Benthic foraminifera baseline assemblages from a coastal nearshore reef complex on the central Great Barrier Reef

    Science.gov (United States)

    Johnson, Jamie; Perry, Chris; Smithers, Scott; Morgan, Kyle

    2016-04-01

    Declining water quality due to river catchment modification since European settlement (c. 1850 A.D.) represents a major threat to the health of coral reefs on Australia's Great Barrier Reef (GBR), particularly for those located in the coastal waters of the GBR's inner-shelf. These nearshore reefs are widely perceived to be most susceptible to declining water quality owing to their close proximity to river point sources. Despite this, nearshore reefs have been relatively poorly studied with the impacts and magnitudes of environmental degradation still remaining unclear. This is largely due to ongoing debates concerning the significance of increased sediment yields against naturally high background sedimentary regimes. Benthic foraminifera are increasingly used as tools for monitoring environmental and ecological change on coral reefs. On the GBR, the majority of studies have focussed on the spatial distributions of contemporary benthic foraminiferal assemblages. While baseline assemblages from other environments (e.g. inshore reefs and mangroves) have been described, very few records exist for nearshore reefs. Here, we present preliminary results from the first palaeoecological study of foraminiferal assemblages of nearshore reefs on the central GBR. Cores were recovered from the nearshore reef complex at Paluma Shoals using percussion techniques. Recovery was 100%, capturing the entire Holocene reef sequence of the selected reef structures. Radiocarbon dating and subsequent age-depth modelling techniques were used to identify reef sequences pre-dating European settlement. Benthic foraminifera assemblages were reconstructed from the identified sequences to establish pre-European ecological baselines with the aim of providing a record of foraminiferal distribution during vertical reef accretion and against which contemporary ecological change may be assessed.

  4. Anthropogenic contaminants in Indo-Pacific humpback and Australian snubfin dolphins from the central and southern Great Barrier Reef

    International Nuclear Information System (INIS)

    Cagnazzi, Daniele; Fossi, Maria Cristina; Parra, Guido J.; Harrison, Peter L.; Maltese, Silvia; Coppola, Daniele; Soccodato, Alice; Bent, Michael; Marsili, Letizia

    2013-01-01

    We present the first evidence of accumulation of organochlorine compounds (DDTs, PCBs, HCB) and polycyclic aromatic hydrocarbons (PAHs) in Indo-Pacific humpback and Australian snubfin dolphins from the central and southern Great Barrier Reef. These dolphins are considered by the Great Barrier Marine Park Authority to be high priority species for management. Analyses of biopsy samples, collected from free ranging individuals, showed PAHs levels comparable to those reported from highly industrialized countries. DDTs and HCB were found at low levels, while in some individuals, PCBs were above thresholds over which immunosuppression and reproductive anomalies occur. These results highlight the need for ongoing monitoring of these and other contaminants, and their potential adverse effects on dolphins and other marine fauna. This is particularly important given the current strategic assessment of the Great Barrier Reef World Heritage Area being undertaken by the Australian Government and the Queensland Government. -- Potentially hazardous levels of some coastal contaminants were found in two species of dolphins inhabiting the Great Barrier Reef Marine Park coastal region

  5. Organic biomarkers to describe the major carbon inputs and cycling of organic matter in the central Great Barrier Reef region

    Science.gov (United States)

    Burns, Kathryn; Brinkman, Diane

    2011-06-01

    Controversy surrounds the sources and transport of land derived pollutants in the Great Barrier Reef ecosystem because there is insufficient knowledge of the mechanism of movement of organic contaminants and the cycling of organic matter in this dynamic system. Thus a sediment and sediment trap study was used to describe the composition of resuspended and surface sediments in the south central Great Barrier Reef and its lagoon. This region is characterised by strong tides (6-8 m at Mackay) and trade winds regularly about 15-20 knots. A series of organic biomarkers detailed the cyclical processes of sediment resuspension, recolonising with marine algae and bacteria, packaging into zooplankton faecal pellets and resettlement to sediments where the organics undergo further diagenesis. With each cycle the inshore sediments are diluted with CaCO 3 reef sediments and moved further offshore with the strong ebb tide currents. This results in transport of land derived materials offshore and little storage of organic materials in the lagoon or reef sediments. These processes were detailed by inorganic measurements such as %CaCO 3 and Al/Ca ratios, and by the compositions of hydrocarbon, sterol, alcohol, and fatty acid lipid fractions. Persistent contaminants such as coal dust from a coastal loading facility can be detected in high concentration inshore and decreasing out to the shelf break at 180 m approximately 40 nautical miles offshore. The normal processes would likely be amplified during cyclonic and other storms. The lipids show the sources of carbon to include diatoms and other phytoplankton, creanaerchaeota, sulfate reducing and other bacteria, land plants including mangrove leaves, plus coal dust and other petroleum contaminants.

  6. The importance of coral larval recruitment for the recovery of reefs impacted by cyclone Yasi in the central Great Barrier Reef.

    Directory of Open Access Journals (Sweden)

    Vimoksalehi Lukoschek

    Full Text Available Cyclone Yasi, one of the most severe tropical storms on record, crossed the central Great Barrier Reef (GBR in February 2011, bringing wind speeds of up to 285 km hr⁻¹ and wave heights of at least 10 m, and causing massive destruction to exposed reefs in the Palm Island Group. Following the cyclone, mean (± S.E. hard coral cover ranged from just 2.1 (0.2 % to 5.3 (0.4 % on exposed reefs and no reproductively mature colonies of any species of Acropora remained. Although no fragments of Acropora were found at impacted exposed sites following the cyclone, small juvenile colonies of Acropora (<10 cm diameter were present, suggesting that their small size and compact morphologies enabled them to survive the cyclone. By contrast, sheltered reefs appeared to be unaffected by the cyclone. Mean (± S.E. hard coral cover ranged from 18.2 (2.4 % to 30.0 (1.0 % and a large proportion of colonies of Acropora were reproductively mature. Macroalgae accounted for 8 to 16% of benthic cover at exposed sites impacted by cyclone Yasi but were absent at sheltered sites. Mean (± S.E. recruitment of acroporids to settlement tiles declined from 25.3 (4.8 recruits tile⁻¹ in the pre-cyclone spawning event (2010 to 15.4 (2.2 recruits tile⁻¹ in the first post-cyclone spawning event (2011. Yet, post-cyclone recruitment did not differ between exposed (15.2±2.1 S.E. and sheltered sites (15.6±2.2 S.E., despite the loss of reproductive colonies at the exposed sites, indicating larval input from external sources. Spatial variation in impacts, the survival of small colonies, and larval replenishment to impacted reefs suggest that populations of Acropora have the potential to recover from this severe disturbance, provided that the Palm Islands are not impacted by acute disturbances or suffer additional chronic stressors in the near future.

  7. Soft coral abundance on the central Great Barrier Reef: effects of Acanthaster planci, space availability, and aspects of the physical environment

    Science.gov (United States)

    Fabricius, K. E.

    1997-07-01

    The distribution and abundance of soft coral genera on reefs of the central Great Barrier Reef was investigated in relation to reef position, recent history of disturbance, wave exposure, substratum slope and depth. Eighty-five 25 m long transects were surveyed at 10 m depth on windward sides of 14 mid- and outer-shelf reefs. A further 75 transects in different zones on one mid-shelf reef (Davies Reef) between 5 and 30 m depth were investigated. The crown-of-thorns starfish Acanthaster planci had caused large-scale mortality of scleractinians on eight of these reefs five to ten years prior to the study, and as a result, scleractinian cover was only 35-55% of that on the six unimpacted reefs. On the impacted reefs, stony corals with massive and encrusting growths form had smaller average colony diameters but similar or slightly lower numerical abundance. In contrast, mean colony size, cover and abundance of branching stony corals showed no difference between impacted and unimpacted reefs. Twenty-four genera of soft corals (in eight families) were recorded, and none showed different abundance or cover in areas of former A. planci impact, compared to unaffected sites. Similarly, no difference was detected among locations in the numbers or area cover of sponges, tunicates, zoanthids, Halimeda or other macro-algae. Mean soft coral cover was 2 to 5% at 10 m on sheltered mid-shelf reefs, and 12 to 17% on more current-exposed reefs. Highest cover and abundances generally occurred on platforms of outer-shelf reefs exposed to relatively strong currents but low wave energy. On Davies Reef, cover and colony numbers of the families Nephtheidae and Xeniidae were low within the zone of wave impact, in flow-protected bays and lagoons, on shaded steep slopes, and at depths above 10 and below 25 m. In contrast, distributions of genera of the family Alcyoniidae were not related to these physical parameters. The physical conditions of a large proportion of habitats appear "sub

  8. Exposure of inshore corals to suspended sediments due to wave-resuspension and river plumes in the central Great Barrier Reef: A reappraisal

    Science.gov (United States)

    Orpin, Alan R.; Ridd, Peter V.

    2012-09-01

    Suspended sediment in the coastal zone is an important limiting factor for the growth and health of inshore coral reefs. The Great Barrier Reef (GBR) lagoon receives sediment from a number of tropical rivers and the physical and biological effects of riverine discharge and turbidity within the lagoon are of considerable scientific and public interest. Published data from two inshore regions of the GBR are reviewed herein to evaluate the relative influence of river plumes and wave resuspension on suspended sediment concentration (SSC) around coral communities over a range of timescales. Data from Cleveland Bay and from other sites near the mouth of the Tully River show that wave resuspension is the most dominant mechanism controlling SSC at inshore reefs. At many nearshore areas today fine-grained bed sediment is abundant, consistent with millennial-scale geological evidence of sediment dispersal prior to European settlement and catchment impacts. Flocculation, particle settling and dilution occurs within the river plume, and riverine sediment concentrations at reefs directly attributable to individual flood inputs is significantly reduced, suggesting that the plume component is a relatively small contribution to the total suspended sediment mass balance over inter-annual timescales. Resuspension events can generate higher ambient SSC than that measured in flood waters (e.g. Tully River). In addition, while visually spectacular, satellite and aerial images offer limited quantitative information of total sediment load carried by hypopycnal plumes, as many of these plumes may contain algal blooms but relatively low concentrations of suspended sediment (ca. processes common to many continental shelves globally. Despite the examples examined in detail herein, the role of frequency, magnitude and duration in determining the impact or exposure of corals to elevated SSCs is poorly constrained by limited quantitative measurements during events, and our ability to place

  9. Climate change and the Great Barrier Reef

    International Nuclear Information System (INIS)

    Johnson, Johanna; Marshall, Paul

    2007-01-01

    Full text: Full text: Climate change is now recognised as the greatest long-term threat to the Great Barrier Reef (GBR). Managers face a future in which the impacts of climate change on tropical marine ecosystems are becoming increasingly frequent and severe. Further degradation is inevitable as the climate continues to change but the extent of the decline will depend on the rate and magnitude of climate change and the resilience of the ecosystem. Changes to the ecosystem have implications for the industries and regional communities that depend on the GBR. Climate projections for the GBR region include increasing air and sea temperatures, ocean acidification, nutrient enrichment (via changes in rainfall), altered light levels, more extreme weather events, changes to ocean circulation and sea level rise. Impacts have already been observed, with severe coral bleaching events in 1998 and 2002, and mass mortalities of seabirds linked to anomalously warm summer conditions. Climate change also poses significant threats to the industries and communities that depend on the GBR ecosystem, both directly and indirectly through loss of natural resources; industries such as recreational and commercial fishing, and tourism, which contributes to a regional tourism industry worth $6.1 billion (Access Economics 2005). A vulnerability assessment undertaken by leading experts in climate and marine science identified climate sensitivities for GBR species, habitats, key processes, GBR industries and communities (Johnson and Marshall 2007). This information has been used to develop a Climate Change Action Plan for the GBR. The Action Plan is a five-year program aimed at facilitating targeted science, building a resilient ecosystem, assisting adaptation of industries and communities, and reducing climate footprints. The Action Plan identifies strategies to review current management arrangements and raise awareness of the issue in order to work towards a resilient ecosystem. Integral to

  10. The exposure of the Great Barrier Reef to ocean acidification

    KAUST Repository

    Mongin, Mathieu; Baird, Mark E.; Tilbrook, Bronte; Matear, Richard J.; Lenton, Andrew; Herzfeld, Mike; Wild-Allen, Karen; Skerratt, Jenny; Margvelashvili, Nugzar; Robson, Barbara J.; Duarte, Carlos M.; Gustafsson, Malin S. M.; Ralph, Peter J.; Steven, Andrew D. L.

    2016-01-01

    The Great Barrier Reef (GBR) is founded on reef-building corals. Corals build their exoskeleton with aragonite, but ocean acidification is lowering the aragonite saturation state of seawater (Ωa). The downscaling of ocean acidification projections

  11. Herbicides: A new threat to the Great Barrier Reef

    International Nuclear Information System (INIS)

    Lewis, Stephen E.; Brodie, Jon E.; Bainbridge, Zoe T.; Rohde, Ken W.; Davis, Aaron M.; Masters, Bronwyn L.; Maughan, Mirjam; Devlin, Michelle J.; Mueller, Jochen F.; Schaffelke, Britta

    2009-01-01

    The runoff of pesticides (insecticides, herbicides and fungicides) from agricultural lands is a key concern for the health of the iconic Great Barrier Reef, Australia. Relatively low levels of herbicide residues can reduce the productivity of marine plants and corals. However, the risk of these residues to Great Barrier Reef ecosystems has been poorly quantified due to a lack of large-scale datasets. Here we present results of a study tracing pesticide residues from rivers and creeks in three catchment regions to the adjacent marine environment. Several pesticides (mainly herbicides) were detected in both freshwater and coastal marine waters and were attributed to specific land uses in the catchment. Elevated herbicide concentrations were particularly associated with sugar cane cultivation in the adjacent catchment. We demonstrate that herbicides reach the Great Barrier Reef lagoon and may disturb sensitive marine ecosystems already affected by other pressures such as climate change. - Herbicide residues have been detected in Great Barrier Reef catchment waterways and river water plumes which may affect marine ecosystems.

  12. Wave attenuation over the Great Barrier Reef matrix

    NARCIS (Netherlands)

    Gallop, S.; Young, I.; Ranasinghe, Ranasinghe W M R J B; Durrant, T.; Haigh, I.; Mynett, Arthur

    2015-01-01

    This is the first large-scale study of the influence of an offshore reef matrix on wave transmission. The focus was on the Great Barrier Reef (GBR), Australia, utilizing a 16 yr-record of wave height, from seven satellite altimeters. Within the GBR matrix, wave height is not strongly dependent on

  13. Low calcification in corals in the Great Barrier Reef

    Science.gov (United States)

    Bhattacharya, Atreyee

    2012-10-01

    Reef-building coral communities in the Great Barrier Reef—the world's largest coral reef—may now be calcifying at only about half the rate that they did during the 1970s, even though live coral cover may not have changed over the past 40 years, a new study finds. In recent decades, coral reefs around the world, home to large numbers of fish and other marine species, have been threatened by such human activities as pollution, overfishing, global warming, and ocean acidification; the latter affects ambient water chemistry and availability of calcium ions, which are critical for coral communities to calcify, build, and maintain reefs. Comparing data from reef surveys during the 1970s, 1980s, and 1990s with present-day (2009) measurements of calcification rates in One Tree Island, a coral reef covering 13 square kilometers in the southern part of the Great Barrier Reef, Silverman et al. show that the total calcification rates (the rate of calcification minus the rate of dissolution) in these coral communities have decreased by 44% over the past 40 years; the decrease appears to stem from a threefold reduction in calcification rates during nighttime.

  14. Connectivity and systemic resilience of the Great Barrier Reef.

    Directory of Open Access Journals (Sweden)

    Karlo Hock

    2017-11-01

    Full Text Available Australia's iconic Great Barrier Reef (GBR continues to suffer from repeated impacts of cyclones, coral bleaching, and outbreaks of the coral-eating crown-of-thorns starfish (COTS, losing much of its coral cover in the process. This raises the question of the ecosystem's systemic resilience and its ability to rebound after large-scale population loss. Here, we reveal that around 100 reefs of the GBR, or around 3%, have the ideal properties to facilitate recovery of disturbed areas, thereby imparting a level of systemic resilience and aiding its continued recovery. These reefs (1 are highly connected by ocean currents to the wider reef network, (2 have a relatively low risk of exposure to disturbances so that they are likely to provide replenishment when other reefs are depleted, and (3 have an ability to promote recovery of desirable species but are unlikely to either experience or spread COTS outbreaks. The great replenishment potential of these 'robust source reefs', which may supply 47% of the ecosystem in a single dispersal event, emerges from the interaction between oceanographic conditions and geographic location, a process that is likely to be repeated in other reef systems. Such natural resilience of reef systems will become increasingly important as the frequency of disturbances accelerates under climate change.

  15. The exposure of the Great Barrier Reef to ocean acidification

    Science.gov (United States)

    Mongin, Mathieu; Baird, Mark E.; Tilbrook, Bronte; Matear, Richard J.; Lenton, Andrew; Herzfeld, Mike; Wild-Allen, Karen; Skerratt, Jenny; Margvelashvili, Nugzar; Robson, Barbara J.; Duarte, Carlos M.; Gustafsson, Malin S. M.; Ralph, Peter J.; Steven, Andrew D. L.

    2016-01-01

    The Great Barrier Reef (GBR) is founded on reef-building corals. Corals build their exoskeleton with aragonite, but ocean acidification is lowering the aragonite saturation state of seawater (Ωa). The downscaling of ocean acidification projections from global to GBR scales requires the set of regional drivers controlling Ωa to be resolved. Here we use a regional coupled circulation–biogeochemical model and observations to estimate the Ωa experienced by the 3,581 reefs of the GBR, and to apportion the contributions of the hydrological cycle, regional hydrodynamics and metabolism on Ωa variability. We find more detail, and a greater range (1.43), than previously compiled coarse maps of Ωa of the region (0.4), or in observations (1.0). Most of the variability in Ωa is due to processes upstream of the reef in question. As a result, future decline in Ωa is likely to be steeper on the GBR than currently projected by the IPCC assessment report. PMID:26907171

  16. The exposure of the Great Barrier Reef to ocean acidification

    KAUST Repository

    Mongin, Mathieu

    2016-02-23

    The Great Barrier Reef (GBR) is founded on reef-building corals. Corals build their exoskeleton with aragonite, but ocean acidification is lowering the aragonite saturation state of seawater (Ωa). The downscaling of ocean acidification projections from global to GBR scales requires the set of regional drivers controlling Ωa to be resolved. Here we use a regional coupled circulation–biogeochemical model and observations to estimate the Ωa experienced by the 3,581 reefs of the GBR, and to apportion the contributions of the hydrological cycle, regional hydrodynamics and metabolism on Ωa variability. We find more detail, and a greater range (1.43), than previously compiled coarse maps of Ωa of the region (0.4), or in observations (1.0). Most of the variability in Ωa is due to processes upstream of the reef in question. As a result, future decline in Ωa is likely to be steeper on the GBR than currently projected by the IPCC assessment report.

  17. Regional economic integration in Great East Asia: determinants and barriers

    Directory of Open Access Journals (Sweden)

    Volodymyr Korol

    2015-06-01

    Full Text Available The article studies both general trends and peculiar characteristics of processes of economic integration in the Great East Asia, which plays the role of one of the major centers of contemporary global development. The basic determinants and barriers for implementation of regional strategies by China, Japan, ASEAN that will influence the geo-economic policy of Ukraine not only in East Asian, but also European and Eurasian areas. Attention is focused on the basic principles of realized and potential future integration models in the "ASEAN+" format with variable composition of member states that correspond to different extents to strategic objectives of both specified key actors in the region and extra-regional states that have global and transnational interests. Extrapolation of dominant trends in the nature and dynamics of transformation processes of East Asian economic regionalization allowed forming a forecast for the longterm conservation of importance of free trade agreements in the absence of preconditions to create customs unions. At the same time it was stressed out that proper assurance of national interests of international economic relations will be based on contractual instruments at the international level, without creating institutional and legal superstructure similar to the European Union or the Eurasian Economic Union as supranational law and supranational bodies.

  18. The New Great Game in Muslim Central Asia

    Science.gov (United States)

    1996-01-01

    and maci]ine tools, petrol - chemicals, agro-processing and textiles. ’’~ 14 THE NEW GREAT GAME IN MUSLIM CENTRAL ASIA Kazakhstan is well endowed...Algeria, Tunisia , and Morocco---are keeping a wary eye. But at the popular level, this pan-Islmnism has the potential to attract a considerable amount of

  19. GEOMORPHIC CONTROLS ON MEADOW ECOSYSTEMS IN THE CENTRAL GREAT BASIN

    Science.gov (United States)

    Wet meadows, riparian corridor phreatophyte assemblages, and high-altitude spring-fed aspen meadows comprise a very small percentage of the total landscape of the mountain ranges in the central Great Basin however, they represent important ecological environments. We have used s...

  20. Potential corridors and barriers for plague spread in central Asia

    Science.gov (United States)

    2013-01-01

    Background Plague (Yersinia pestis infection) is a vector-borne disease which caused millions of human deaths in the Middle Ages. The hosts of plague are mostly rodents, and the disease is spread by the fleas that feed on them. Currently, the disease still circulates amongst sylvatic rodent populations all over the world, including great gerbil (Rhombomys opimus) populations in Central Asia. Great gerbils are social desert rodents that live in family groups in burrows, which are visible on satellite images. In great gerbil populations an abundance threshold exists, above which plague can spread causing epizootics. The spatial distribution of the host species is thought to influence the plague dynamics, such as the direction of plague spread, however no detailed analysis exists on the possible functional or structural corridors and barriers that are present in this population and landscape. This study aims to fill that gap. Methods Three 20 by 20 km areas with known great gerbil burrow distributions were used to analyse the spatial distribution of the burrows. Object-based image analysis was used to map the landscape at several scales, and was linked to the burrow maps. A novel object-based method was developed – the mean neighbour absolute burrow density difference (MNABDD) – to identify the optimal scale and evaluate the efficacy of using landscape objects as opposed to square cells. Multiple regression using raster maps was used to identify the landscape-ecological variables that explain burrow density best. Functional corridors and barriers were mapped using burrow density thresholds. Cumulative resistance of the burrow distribution to potential disease spread was evaluated using cost distance analysis. A 46-year plague surveillance dataset was used to evaluate whether plague spread was radially symmetric. Results The burrow distribution was found to be non-random and negatively correlated with Greenness, especially in the floodplain areas. Corridors and

  1. Molecular confirmation of hybridization between Dascyllus reticulatus × Dascyllus aruanus from the Great Barrier Reef

    KAUST Repository

    He, Song; Johansen, Jacob L.; Hoey, Andrew S.; Pappas, Melissa; Berumen, Michael L.

    2017-01-01

    To date, more than 81 species of tropical coral reef fish have been reported to hybridize in nature, spanning multiple families, including the Chaetodontidae, Pomacanthidae, and Labridae. Hybridization, however, is seemingly rare among benthic nesting species that engage in pair spawning, such as the Pomacentridae. Here, we present evidence for the first molecularly confirmed record of hybridization within the genus Dascyllus; D. aruanus and D. reticulatus. Interestingly, although many hybridization events are attributed to peripheral range effects or areas of limited overlap among otherwise allopatric species, this hybrid individual was collected from the northern Great Barrier Reef, centrally located within the distribution ranges of both species. The hybrid exhibited coloration and meristic counts intermediate between D. aruanus and D. reticulatus. Diagnostic genetic markers and subsequent microsatellites analysis confirmed that this individual was a hybrid offspring of D. aruanus and D. reticulatus, with the latter providing the maternal contribution. The occurrence of the D. aruanus × D. reticulatus hybrid on the Great Barrier Reef represents an exception to the otherwise species-specific haplotypes. The nuclear diagnostic marker which was identified during this study could serve as a hybrid indicator and benefit future hybrid investigations for hybridization between these two species.

  2. Molecular confirmation of hybridization between Dascyllus reticulatus × Dascyllus aruanus from the Great Barrier Reef

    KAUST Repository

    He, Song

    2017-11-17

    To date, more than 81 species of tropical coral reef fish have been reported to hybridize in nature, spanning multiple families, including the Chaetodontidae, Pomacanthidae, and Labridae. Hybridization, however, is seemingly rare among benthic nesting species that engage in pair spawning, such as the Pomacentridae. Here, we present evidence for the first molecularly confirmed record of hybridization within the genus Dascyllus; D. aruanus and D. reticulatus. Interestingly, although many hybridization events are attributed to peripheral range effects or areas of limited overlap among otherwise allopatric species, this hybrid individual was collected from the northern Great Barrier Reef, centrally located within the distribution ranges of both species. The hybrid exhibited coloration and meristic counts intermediate between D. aruanus and D. reticulatus. Diagnostic genetic markers and subsequent microsatellites analysis confirmed that this individual was a hybrid offspring of D. aruanus and D. reticulatus, with the latter providing the maternal contribution. The occurrence of the D. aruanus × D. reticulatus hybrid on the Great Barrier Reef represents an exception to the otherwise species-specific haplotypes. The nuclear diagnostic marker which was identified during this study could serve as a hybrid indicator and benefit future hybrid investigations for hybridization between these two species.

  3. Late Pleistocene dune activity in the central Great Plains, USA

    Science.gov (United States)

    Mason, J.A.; Swinehart, J.B.; Hanson, P.R.; Loope, D.B.; Goble, R.J.; Miao, X.; Schmeisser, R.L.

    2011-01-01

    Stabilized dunes of the central Great Plains, especially the megabarchans and large barchanoid ridges of the Nebraska Sand Hills, provide dramatic evidence of late Quaternary environmental change. Episodic Holocene dune activity in this region is now well-documented, but Late Pleistocene dune mobility has remained poorly documented, despite early interpretations of the Sand Hills dunes as Pleistocene relicts. New optically stimulated luminescence (OSL) ages from drill cores and outcrops provide evidence of Late Pleistocene dune activity at sites distributed across the central Great Plains. In addition, Late Pleistocene eolian sands deposited at 20-25 ka are interbedded with loess south of the Sand Hills. Several of the large dunes sampled in the Sand Hills clearly contain a substantial core of Late Pleistocene sand; thus, they had developed by the Late Pleistocene and were fully mobile at that time, although substantial sand deposition and extensive longitudinal dune construction occurred during the Holocene. Many of the Late Pleistocene OSL ages fall between 17 and 14 ka, but it is likely that these ages represent only the later part of a longer period of dune construction and migration. At several sites, significant Late Pleistocene or Holocene large-dune migration also probably occurred after the time represented by the Pleistocene OSL ages. Sedimentary structures in Late Pleistocene eolian sand and the forms of large dunes potentially constructed in the Late Pleistocene both indicate sand transport dominated by northerly to westerly winds, consistent with Late Pleistocene loess transport directions. Numerical modeling of the climate of the Last Glacial Maximum has often yielded mean monthly surface winds southwest of the Laurentide Ice Sheet that are consistent with this geologic evidence, despite strengthened anticyclonic circulation over the ice sheet. Mobility of large dunes during the Late Pleistocene on the central Great Plains may have been the result of

  4. Coral Reef Community Composition in the Context of Disturbance History on the Great Barrier Reef, Australia

    Science.gov (United States)

    Graham, Nicholas A. J.; Chong-Seng, Karen M.; Huchery, Cindy; Januchowski-Hartley, Fraser A.; Nash, Kirsty L.

    2014-01-01

    Much research on coral reefs has documented differential declines in coral and associated organisms. In order to contextualise this general degradation, research on community composition is necessary in the context of varied disturbance histories and the biological processes and physical features thought to retard or promote recovery. We conducted a spatial assessment of coral reef communities across five reefs of the central Great Barrier Reef, Australia, with known disturbance histories, and assessed patterns of coral cover and community composition related to a range of other variables thought to be important for reef dynamics. Two of the reefs had not been extensively disturbed for at least 15 years prior to the surveys. Three of the reefs had been severely impacted by crown-of-thorns starfish outbreaks and coral bleaching approximately a decade before the surveys, from which only one of them was showing signs of recovery based on independent surveys. We incorporated wave exposure (sheltered and exposed) and reef zone (slope, crest and flat) into our design, providing a comprehensive assessment of the spatial patterns in community composition on these reefs. Categorising corals into life history groupings, we document major coral community differences in the unrecovered reefs, compared to the composition and covers found on the undisturbed reefs. The recovered reef, despite having similar coral cover, had a different community composition from the undisturbed reefs, which may indicate slow successional processes, or a different natural community dominance pattern due to hydrology and other oceanographic factors. The variables that best correlated with patterns in the coral community among sites included the density of juvenile corals, herbivore fish biomass, fish species richness and the cover of macroalgae. Given increasing impacts to the Great Barrier Reef, efforts to mitigate local stressors will be imperative to encouraging coral communities to persist into

  5. Climate change and environmentally responsible behavior on the Great Barrier Reef, Australia

    Science.gov (United States)

    Jee In Yoon; Gerard Kyle; Carena J. vanRiper; Stephen G. Sutton

    2012-01-01

    This study explored the relationship between Australians' perceptions of climate change, its impact on the Great Barrier Reef (GBR), and predictors of environmentally responsible behavior (ERB). Our hypothesized model suggested that general attitudes toward climate change, social pressure for engaging in ERBs (subjective norms), and perceived behavioral control (...

  6. The Great Barrier Reef:The chronological record from a new borehole

    NARCIS (Netherlands)

    Braithwaite, C.J.; Dalmasso, H.; Gilmour, M.A.; Harkness, D.D.; Henderson, G.M.; Kay, R.L.F.; Kroon, D.; Montaggioni, L.F.; Wilson, P.A.

    2004-01-01

    A new borehole, 210 mbsf (meters below sea floor) deep, drilled in Ribbon Reef 5 on the Great Barrier Reef off Cooktown, NE Australia, reveals a shallowing-upwards succession, the younger part of which is punctuated by a series of erosion surfaces. Nine depositional units have been defined by

  7. Antifoulant (butyltin and copper) concentrations in sediments from the Great Barrier Reef World Heritage Area, Australia

    International Nuclear Information System (INIS)

    Haynes, David; Loong, Dominica

    2002-01-01

    Antifoulant concentrations are generally low in the Great Barrier Reef, although ship grounding sites present a previously unidentified significant source of antifoulant pollutants in the Great Barrier Reef. - Antifoulant concentrations were determined in marine sediments collected from commercial harbours, marinas, mooring locations on mid-shelf continental islands, and outer reef sites in four regions within the Great Barrier Reef World Heritage Area in 1999. Highest copper concentrations were present in sediments collected from commercial harbour sampling sites (28-233 μg Cu g -1 dry wt.). In contrast, copper concentrations in sediments collected from boat mooring sites on mid-shelf continental islands and outer reef sites were at background concentrations (i.e. -1 dry wt.). Butyltin was only detectable in four of the 42 sediments sampled for analysis, and was only present in sediments collected from commercial harbours (18-1275 ng Sn g -1 dry wt.) and from marinas (4-5 ng Sn g -1 dry wt.). The detection of tributyltin at marina sites implies that this antifoulant may continue to be used illegally on the hulls of smaller recreational vessels. Sediment samples were also collected opportunistically from the site of a 22,000 t cargo ship grounding in May 1999 at Heath Reef, in the far northern Great Barrier Reef. Butyltin concentrations were grossly elevated (660-340,000 ng Sn g -1 dry wt.) at the grounding site. The impact of residual antifoulants at large ship grounding sites should be recognised as a significant, long-term environmental problem unless antfoulant clean-up strategies are undertaken

  8. The evolution of the Great Barrier Reef during the Last Interglacial Period

    Science.gov (United States)

    Dechnik, Belinda; Webster, Jody M.; Webb, Gregory E.; Nothdurft, Luke; Dutton, Andrea; Braga, Juan-Carlos; Zhao, Jian-xin; Duce, Stephanie; Sadler, James

    2017-02-01

    Reef response to Last Interglacial (LIG) sea level and palaeoenvironmental change has been well documented at a limited number of far-field sites remote from former ice sheets. However, the age and development of LIG reefs in the Great Barrier Reef (GBR) remain poorly understood due to their location beneath modern living reefs. Here we report thirty-nine new mass spectrometry U-Th ages from seven LIG platform reefs across the northern, central and southern GBR. Two distinct geochemical populations of corals were observed, displaying activity ratios consistent with either closed or open system evolution. Our closed-system ages ( 129-126 ka) provide the first reliable LIG ages for the entire GBR. Combined with our open-system model ages, we are able to constrain the interval of significant LIG reef growth in the southern GBR to between 129-121 ka. Using age-elevation data in conjunction with newly defined coralgal assemblages and sedimentary facies analysis we have defined three distinct phases of LIG reef development in response to major sea level and oceanographic changes. These phases include: Phase 1 (> 129 ka), a shallow-water coralgal colonisation phase following initial flooding of the older, likely Marine Isotope Stage 7 (MIS7) antecedent platform; Phase 2 ( 129 ka), a near drowning event in response to rapid sea level rise and greater nutrient-rich upwelling and; Phase 3 ( 128-121 ka), establishment of significant reef framework through catch-up reef growth, initially characterised by deeper, more turbid coralgal assemblages (Phase 3a) that transition to shallow-water assemblages following sea level stabilisation (Phase 3b). Coralgal assemblage analysis indicates that the palaeoenvironments during initial reef growth phases (1 and 2) of the LIG were significantly different than the initial reef growth phases in the Holocene. However, the similar composition of ultimate shallow-water coralgal assemblages and slow reef accretion rates following stabilisation

  9. Inferring coastal processes from regional-scale mapping of 222Radon and salinity: examples from the Great Barrier Reef, Australia

    International Nuclear Information System (INIS)

    Stieglitz, Thomas C.; Cook, Peter G.; Burnett, William C.

    2010-01-01

    The radon isotope 222 Rn and salinity in coastal surface water were mapped on regional scales, to improve the understanding of coastal processes and their spatial variability. Radon was measured with a surface-towed, continuously recording multi-detector setup on a moving vessel. Numerous processes and locations of land-ocean interaction along the Central Great Barrier Reef coastline were identified and interpreted based on the data collected. These included riverine fluxes, terrestrially-derived fresh submarine groundwater discharge (SGD) and the tidal pumping of seawater through mangrove forests. Based on variations in the relationship of the tracers radon and salinity, some aspects of regional freshwater inputs to the coastal zone and to estuaries could be assessed. Concurrent mapping of radon and salinity allowed an efficient qualitative assessment of land-ocean interaction on various spatial and temporal scales, indicating that such surveys on coastal scales can be a useful tool to obtain an overview of SGD locations and processes.

  10. Keeping the ‘Great’ in the Great Barrier Reef: large-scale governance of the Great Barrier Reef Marine Park

    Directory of Open Access Journals (Sweden)

    Louisa S. Evans

    2014-08-01

    Full Text Available As part of an international collaboration to compare large-scale commons, we used the Social-Ecological Systems Meta-Analysis Database (SESMAD to systematically map out attributes of and changes in the Great Barrier Reef Marine Park (GBRMP in Australia. We focus on eight design principles from common-pool resource (CPR theory and other key social-ecological systems governance variables, and explore to what extent they help explain the social and ecological outcomes of park management through time. Our analysis showed that commercial fisheries management and the re-zoning of the GBRMP in 2004 led to improvements in ecological condition of the reef, particularly fisheries. These boundary and rights changes were supported by effective monitoring, sanctioning and conflict resolution. Moderate biophysical connectivity was also important for improved outcomes. However, our analysis also highlighted that continued challenges to improved ecological health in terms of coral cover and biodiversity can be explained by fuzzy boundaries between land and sea, and the significance of external drivers to even large-scale social-ecological systems (SES. While ecological and institutional fit in the marine SES was high, this was not the case when considering the coastal SES. Nested governance arrangements become even more important at this larger scale. To our knowledge, our paper provides the first analysis linking the re-zoning of the GBRMP to CPR and SES theory. We discuss important challenges to coding large-scale systems for meta-analysis.

  11. Large-scale bleaching of corals on the Great Barrier Reef.

    Science.gov (United States)

    Hughes, T P; Kerry, J T; Simpson, T

    2018-02-01

    In 2015-2016, record temperatures triggered a pan-tropical episode of coral bleaching. In the southern hemisphere summer of March-April 2016, we used aerial surveys to measure the level of bleaching on 1,156 individual reefs throughout the 2,300 km length of the Great Barrier Reef, the world's largest coral reef system. The accuracy of the aerial scores was ground-truthed with detailed underwater surveys of bleaching at 260 sites (104 reefs), allowing us to compare aerial and underwater bleaching data with satellite-derived temperatures and with associated model predictions of bleaching. The severity of bleaching on individual reefs in 2016 was tightly correlated with the level of local heat exposure: the southernmost region of the Great Barrier Reef escaped with only minor bleaching because summer temperatures there were close to average. Gradients in nutrients and turbidity from inshore to offshore across the Great Barrier Reef had minimal effect on the severity of bleaching. Similarly, bleaching was equally severe on reefs that are open or closed to fishing, once the level of satellite-derived heat exposure was accounted for. The level of post-bleaching mortality, measured underwater after 7-8 months, was tightly correlated with the aerial scores measured at the peak of bleaching. Similarly, reefs with a high aerial bleaching score also experienced major shifts in species composition due to extensive mortality of heat-sensitive species. Reefs with low bleaching scores did not change in composition, and some showed minor increases in coral cover. Two earlier mass bleaching events occurred on the Great Barrier Reef in 1998 and 2002, that were less severe than 2016. In 2016, bleaching, compared to 42% in 2002 and 44% in 1998. Conversely, the proportion of reefs that were severely bleached (>60% of corals affected) was four times higher in 2016. The geographic footprint of each of the three events is distinctive, and matches satellite-derived sea surface

  12. SPATIAL HETEROGENEITY OF PHOTOSYNTHETIC ACTIVITY WITHIN DISEASED CORALS FROM THE GREAT BARRIER REEF

    DEFF Research Database (Denmark)

    Roff, George; Ulstrup, Karin Elizabeth; Fine, Maoz

    2008-01-01

    Morphological diagnosis and descriptions of seven disease-like syndromes affecting scleractinian corals were characterized from the southern Great Barrier Reef (GBR). Chl a fluorescence of PSII was measured using an Imaging-PAM (pulse amplitude modulated) fluorometer, enabling visualization...... with white patch syndrome appeared to impact primarily on the symbiotic dinoflagellates, as evidenced by declines in minimum fluorescence (F0) and maximum quantum yield (Fv/Fm), with no indication of degeneration in the host tissues. Our results suggest that for the majority of coral syndromes from the GBR......, pathogenesis occurs in the host tissue, while the impact on the zooxanthellae populations residing in affected corals is minimal....

  13. Origins and Implications of a Primary Crown-of-Thorns Starfish Outbreak in the Southern Great Barrier Reef

    Directory of Open Access Journals (Sweden)

    Ian Miller

    2015-01-01

    Full Text Available The crown-of-thorns starfish (COTS is a major predator of hard corals. Repeated COTS outbreaks in the Cairns and Central sections of the Great Barrier Reef (GBR have been responsible for greater declines in coral cover than any other type of disturbance, including cyclones, disease, and coral bleaching. Knowledge of the precise timing and location of primary outbreaks could reveal the initial drivers of outbreaks and so could indicate possible management measures. In the central GBR, COTS outbreaks appear to follow major flooding events, but despite many years of observations, no primary outbreak has ever been unequivocally identified in the central and northern GBR. Here we locate a primary outbreak of COTS on the southern GBR which is not correlated with flooding. Instead it appears to have been the result of a combination of life history traits of COTS and prevailing oceanographic conditions. The hydrodynamic setting implies that the outbreak could disperse larvae to other reefs in the region.

  14. Integrating observational and modelling systems for the management of the Great Barrier Reef

    Science.gov (United States)

    Baird, M. E.; Jones, E. M.; Margvelashvili, N.; Mongin, M.; Rizwi, F.; Robson, B.; Schroeder, T.; Skerratt, J.; Steven, A. D.; Wild-Allen, K.

    2016-02-01

    Observational and modelling systems provide two sources of knowledge that must be combined to provide a more complete view than either observations or models alone can provide. Here we describe the eReefs coupled hydrodynamic, sediment and biogeochemical model that has been developed for the Great Barrier Reef; and the multiple observations that are used to constrain the model. Two contrasting examples of model - observational integration are highlighted. First we explore the carbon chemistry of the waters above the reef, for which observations are accurate, but expensive and therefore sparse, while model behaviour is highly skilful. For carbon chemistry, observations are used to constrain model parameterisation and quantify model error, with the model output itself providing the most useable knowledge for management purposes. In contrast, ocean colour provides inaccurate, but cheap and spatially and temporally extensive observations. Thus observations are best combined with the model in a data assimilating framework, where a custom-designed optical model has been developed for the purposes of incorporating ocean colour observations. The future management of Great Barrier Reef water quality will be based on an integration of observing and modelling systems, providing the most robust information available.

  15. Coral skeletons provide historical evidence of phosphorus runoff on the great barrier reef.

    Directory of Open Access Journals (Sweden)

    Jennie Mallela

    Full Text Available Recently, the inshore reefs of the Great Barrier Reef have declined rapidly because of deteriorating water quality. Increased catchment runoff is one potential culprit. The impacts of land-use on coral growth and reef health however are largely circumstantial due to limited long-term data on water quality and reef health. Here we use a 60 year coral core record to show that phosphorus contained in the skeletons (P/Ca of long-lived, near-shore Porites corals on the Great Barrier Reef correlates with annual records of fertiliser application and particulate phosphorus loads in the adjacent catchment. Skeletal P/Ca also correlates with Ba/Ca, a proxy for fluvial sediment loading, again linking near-shore phosphorus records with river runoff. Coral core records suggest that phosphorus levels increased 8 fold between 1949 and 2008 with the greatest levels coinciding with periods of high fertiliser-phosphorus use. Periods of high P/Ca correspond with intense agricultural activity and increased fertiliser application in the river catchment following agricultural expansion and replanting after cyclone damage. Our results demonstrate how coral P/Ca records can be used to assess terrestrial nutrient loading of vulnerable near-shore reefs.

  16. Deepwater Chondrichthyan Bycatch of the Eastern King Prawn Fishery in the Southern Great Barrier Reef, Australia.

    Directory of Open Access Journals (Sweden)

    Cassandra L Rigby

    Full Text Available The deepwater chondrichthyan fauna of the Great Barrier Reef is poorly known and life history information is required to enable their effective management as they are inherently vulnerable to exploitation. The chondrichthyan bycatch from the deepwater eastern king prawn fishery at the Swain Reefs in the southern Great Barrier Reef was examined to determine the species present and provide information on their life histories. In all, 1533 individuals were collected from 11 deepwater chondrichthyan species, with the Argus skate Dipturus polyommata, piked spurdog Squalus megalops and pale spotted catshark Asymbolus pallidus the most commonly caught. All but one species is endemic to Australia with five species restricted to waters offshore from Queensland. The extent of life history information available for each species varied but the life history traits across all species were characteristic of deep water chondrichthyans with relatively large length at maturity, small litters and low ovarian fecundity; all indicative of low biological productivity. However, variability among these traits and spatial and bathymetric distributions of the species suggests differing degrees of resilience to fishing pressure. To ensure the sustainability of these bycatch species, monitoring of their catches in the deepwater eastern king prawn fishery is recommended.

  17. Cryptofauna of the epilithic algal matrix on an inshore coral reef, Great Barrier Reef

    Science.gov (United States)

    Kramer, M. J.; Bellwood, D. R.; Bellwood, O.

    2012-12-01

    Composed of a collection of algae, detritus, sediment and invertebrates, the epilithic algal matrix (EAM) is an abundant and ubiquitous feature of coral reefs. Despite its prevalence, there is a paucity of information regarding its associated invertebrate fauna. The cryptofaunal invertebrate community of the EAM was quantitatively investigated in Pioneer Bay on Orpheus Island, Great Barrier Reef. Using a vacuum collection method, a diversity of organisms representing 10 different phyla were identified. Crustacea dominated the samples, with harpacticoid copepods being particularly abundant (2025 ± 132 100 cm-2; mean density ± SE). The volume of coarse particulate matter in the EAM was strongly correlated with the abundance of harpacticoid copepods. The estimated biomass of harpacticoid copepods (0.48 ± 0.05 g m-2; wet weight) suggests that this group is likely to be important for reef trophodynamics and nutrient cycling.

  18. Climate change disables coral bleaching protection on the Great Barrier Reef.

    Science.gov (United States)

    Ainsworth, Tracy D; Heron, Scott F; Ortiz, Juan Carlos; Mumby, Peter J; Grech, Alana; Ogawa, Daisie; Eakin, C Mark; Leggat, William

    2016-04-15

    Coral bleaching events threaten the sustainability of the Great Barrier Reef (GBR). Here we show that bleaching events of the past three decades have been mitigated by induced thermal tolerance of reef-building corals, and this protective mechanism is likely to be lost under near-future climate change scenarios. We show that 75% of past thermal stress events have been characterized by a temperature trajectory that subjects corals to a protective, sub-bleaching stress, before reaching temperatures that cause bleaching. Such conditions confer thermal tolerance, decreasing coral cell mortality and symbiont loss during bleaching by over 50%. We find that near-future increases in local temperature of as little as 0.5°C result in this protective mechanism being lost, which may increase the rate of degradation of the GBR. Copyright © 2016, American Association for the Advancement of Science.

  19. Phytotoxicity induced in isolated zooxanthellae by herbicides extracted from Great Barrier Reef flood waters.

    Science.gov (United States)

    Shaw, C M; Brodie, J; Mueller, J F

    2012-01-01

    To date there has been limited evidence anthropogenically sourced pollution from catchments reaching corals of the Great Barrier Reef (GBR). In this study, freshly isolated zooxanthellae were exposed to polar chemicals (chiefly herbicides) extracted from water samples collected in a flood plume in the GBR lagoon. Photosynthetic potential of the isolated zooxanthellae declined after exposure to concentrated extracts (10 times) from all but one of the sampling sites. Photosynthetic potential demonstrated a significant positive relationship with the concentration of diuron in the concentrated extracts and a significant inverse relationship with salinity measured at the sampling site. This study demonstrates that runoff from land based application of herbicides may reduce photosynthetic efficiency in corals of inshore reefs in the GBR. The ecological impacts of the chemicals in combination with other potential stressors on corals remain unclear. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. An assessment of an environmental gradient using coral geochemical records, Whitsunday Islands, Great Barrier Reef, Australia

    International Nuclear Information System (INIS)

    Lewis, S.E.; Brodie, J.E.; McCulloch, M.T.; Mallela, J.; Jupiter, S.D.; Stuart Williams, H.; Lough, J.M.; Matson, E.G.

    2012-01-01

    Coral cores were collected along an environmental and water quality gradient through the Whitsunday Island group, Great Barrier Reef (Australia), for trace element and stable isotope analysis. The primary aim of the study was to examine if this gradient could be detected in coral records and, if so, whether the gradient has changed over time with changing land use in the adjacent river catchments. Y/Ca was the trace element ratio which varied spatially across the gradient, with concentrations progressively decreasing away from the river mouths. The Ba/Ca and Y/Ca ratios were the only indicators of change in the gradient through time, increasing shortly after European settlement. The Mn/Ca ratio responded to local disturbance related to the construction of tourism infrastructure. Nitrogen isotope ratios showed no apparent trend over time. This study highlights the importance of site selection when using coral records to record regional environmental signals.

  1. Guiding principles for the improved governance of port and shipping impacts in the Great Barrier Reef.

    Science.gov (United States)

    Grech, A; Bos, M; Brodie, J; Coles, R; Dale, A; Gilbert, R; Hamann, M; Marsh, H; Neil, K; Pressey, R L; Rasheed, M A; Sheaves, M; Smith, A

    2013-10-15

    The Great Barrier Reef (GBR) region of Queensland, Australia, encompasses a complex and diverse array of tropical marine ecosystems of global significance. The region is also a World Heritage Area and largely within one of the world's best managed marine protected areas. However, a recent World Heritage Committee report drew attention to serious governance problems associated with the management of ports and shipping. We review the impacts of ports and shipping on biodiversity in the GBR, and propose a series of guiding principles to improve the current governance arrangements. Implementing these principles will increase the capacity of decision makers to minimize the impacts of ports and shipping on biodiversity, and will provide certainty and clarity to port operators and developers. A 'business as usual' approach could lead to the GBR's inclusion on the List of World Heritage in Danger in 2014. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Dispersal of adult black marlin (Istiompax indica) from a Great Barrier Reef spawning aggregation.

    Science.gov (United States)

    Domeier, Michael L; Speare, Peter

    2012-01-01

    The black marlin (Istiompax indica) is one of the largest bony fishes in the world with females capable of reaching a mass of over 700 kg. This highly migratory predator occurs in the tropical regions of the Pacific and Indian Oceans, and is the target of regional recreational and commercial fisheries. Through the sampling of ichthyoplankton and ovaries we provide evidence that the relatively high seasonal abundance of black marlin off the Great Barrier Reef is, in fact, a spawning aggregation. Furthermore, through the tracking of individual black marlin via satellite popup tags, we document the dispersal of adult black marlin away from the spawning aggregation, thereby identifying the catchment area for this spawning stock. Although tag shedding is an issue when studying billfish, we tentatively identify the catchment area for this stock of black marlin to extend throughout the Coral Sea, including the waters of Papua New Guinea, the Solomon Islands, Micronesia, New Caledonia, Kiribati, Vanuatu, Fiji, Tuvalu and Nauru.

  3. Sensitivity of coral cays to climatic variations, southern Great Barrier Reef, Australia

    Energy Technology Data Exchange (ETDEWEB)

    Flood, P G

    1986-01-01

    Analysis of available wind data for the years 1962-80 from Heron Island which is located within the southern Great Barrier Reef indicates that the annual wind energy vector has oscillated within a 45 degree arc from the SSE in the early 1960's to ESE in the late 1970's. Such changes in wind direction influence the direction of propagation of the waves which mold the shape of coral sand cays in this region. Documentation is provided which shows that the variability of the shoreline positions on Erskine Island, an uninhabited vegetated sand cays reflects this change. The implication is that contemporary shoreline erosion on Heron Island is not caused by the development associated with the tourist resort there. It is a symptom of the change in the propagation direction of the wind-induced waves which is related to long-term climatic change.

  4. The ecology of 'Acroporid white syndrome', a coral disease from the southern Great Barrier Reef.

    Directory of Open Access Journals (Sweden)

    George Roff

    Full Text Available Outbreaks of coral disease have increased worldwide over the last few decades. Despite this, remarkably little is known about the ecology of disease in the Indo-Pacific Region. Here we report the spatiotemporal dynamics of a coral disease termed 'Acroporid white syndrome' observed to affect tabular corals of the genus Acropora on the southern Great Barrier Reef. The syndrome is characterised by rapid tissue loss initiating in the basal margins of colonies, and manifests as a distinct lesion boundary between apparently healthy tissue and exposed white skeleton. Surveys of eight sites around Heron Reef in 2004 revealed a mean prevalence of 8.1±0.9%, affecting the three common species (Acropora cytherea, A. hyacinthus, A. clathrata and nine other tabular Acropora spp. While all sizes of colonies were affected, white syndrome disproportionately affected larger colonies of tabular Acroporids (>80 cm. The prevalence of white syndrome was strongly related to the abundance of tabular Acroporids within transects, yet the incidence of the syndrome appears unaffected by proximity to other colonies, suggesting that while white syndrome is density dependant, it does not exhibit a strongly aggregated spatial pattern consistent with previous coral disease outbreaks. Acroporid white syndrome was not transmitted by either direct contact in the field or by mucus in aquaria experiments. Monitoring of affected colonies revealed highly variable rates of tissue loss ranging from 0 to 1146 cm(-2 week(-1, amongst the highest documented for a coral disease. Contrary to previous links between temperature and coral disease, rates of tissue loss in affected colonies increased threefold during the winter months. Given the lack of spatial pattern and non-infectious nature of Acroporid white syndrome, further studies are needed to determine causal factors and longer-term implications of disease outbreaks on the Great Barrier Reef.

  5. Ecosystem health of the Great Barrier Reef: Time for effective management action based on evidence

    Science.gov (United States)

    Brodie, Jon; Pearson, Richard G.

    2016-12-01

    The Great Barrier Reef (GBR) is a World Heritage site off the north-eastern coast of Australia. The GBR is worth A 15-20 billion/year to the Australian economy and provides approximately 64,000 full time jobs. Many of the species and ecosystems of the GBR are in poor condition and continue to decline. The principal causes of the decline are catchment pollutant runoff associated with agricultural and urban land uses, climate change impacts and the effects of fishing. Many important ecosystems of the GBR region are not included inside the boundaries of the World Heritage Area. The current management regime for catchment pollutant runoff and climate change is clearly inadequate to prevent further decline. We propose a refocus of management on a "Greater GBR" (containing not only the major ecosystems and species of the GBR, but also its catchment) and on a set of management actions to halt the decline of the GBR. Proposed actions include: (1) Strengthen management in the areas of the Greater GBR where ecosystems are in good condition, with Torres Strait, northern Cape York and Hervey Bay being the systems with highest current integrity; (2) Investigate methods of cross-boundary management to achieve simultaneous cost-effective terrestrial, freshwater and marine ecosystem protection in the Greater GBR; (3) Develop a detailed, comprehensive, costed water quality management plan for the Greater GBR; (4) Use the Great Barrier Reef Marine Park Act and the Environment Protection and Biodiversity Conservation Act to regulate catchment activities that lead to damage to the Greater GBR, in conjunction with the relevant Queensland legislation; (5) Fund catchment and coastal management to the required level to solve pollution issues for the Greater GBR by 2025, before climate change impacts on Greater GBR ecosystems become overwhelming; (6) Continue enforcement of the zoning plan; (7) Australia to show commitment to protecting the Greater GBR through greenhouse gas emissions

  6. Localised human impacts on the Harataonga coastal landscape, Great Barrier Island, northern New Zealand

    International Nuclear Information System (INIS)

    Horrocks, M.; Nichol, S.; Cockrem, J.; Shane, P.

    2008-01-01

    Here we present results of analyses of sediment profiles and cores, and coprolites, from Harataonga Bay, Great Barrier Island. Using a range of analyses (sedimentological, plant microfossils, parasitological, microbial, and steroids and myoglobin) we concentrate on human impact and reconstruction of the geomorphology and vegetation of the near-shore environments. Two different sub--environments are represented: dunes and alluvial plain. Dune instability coincides with a major increase in disturbance-related plants (especially ground ferns) as a result of forest clearance. The present form of much of the Harataonga dunes and the swamp at the eastern end of the bay is directly a result of human impact, no earlier than 737 ± 178 14 C yr BP. In the record from the alluvial plain of the main Harataonga watercourse, at the western end of the bay, it is difficult to clearly resolve sedimentary inputs that directly relate to human presence in this former tidal inlet that was open to storm surge and stream floods. The only exception is the slopewash materials forming the terrace surface, sediments of which bear pollen consistent with vegetation disturbance. The landforms are natural but the rate at which the tidal inlet was infilled to form a terrace was accelerated by human activity. The nature and timing of the localised human impacts at Harataonga are consistent with those observed elsewhere on Great Barrier Island and mainland New Zealand. Some of our techniques (e.g. bacteria, steroids) are newly applied to coprolites in New Zealand but none provided any useful information because of poor preservation. (author). 34 refs., 13 figs., 3 tabs

  7. Joint estimation of crown of thorns (Acanthaster planci densities on the Great Barrier Reef

    Directory of Open Access Journals (Sweden)

    M. Aaron MacNeil

    2016-08-01

    Full Text Available Crown-of-thorns starfish (CoTS; Acanthaster spp. are an outbreaking pest among many Indo-Pacific coral reefs that cause substantial ecological and economic damage. Despite ongoing CoTS research, there remain critical gaps in observing CoTS populations and accurately estimating their numbers, greatly limiting understanding of the causes and sources of CoTS outbreaks. Here we address two of these gaps by (1 estimating the detectability of adult CoTS on typical underwater visual count (UVC surveys using covariates and (2 inter-calibrating multiple data sources to estimate CoTS densities within the Cairns sector of the Great Barrier Reef (GBR. We find that, on average, CoTS detectability is high at 0.82 [0.77, 0.87] (median highest posterior density (HPD and [95% uncertainty intervals], with CoTS disc width having the greatest influence on detection. Integrating this information with coincident surveys from alternative sampling programs, we estimate CoTS densities in the Cairns sector of the GBR averaged 44 [41, 48] adults per hectare in 2014.

  8. Cover crop biomass production and water use in the central great plains under varying water availability

    Science.gov (United States)

    The water-limited environment of the semi-arid central Great Plains may not have potential to produce enough cover crop biomass to generate benefits associated with cover crop use in more humid regions. There have been reports that cover crops grown in mixtures produce more biomass with greater wate...

  9. The Formation of New Monetary Policies: Decisions of Central Banks on the Great Recession

    Directory of Open Access Journals (Sweden)

    Ana Esther Castro

    2014-05-01

    Full Text Available The effect that the Great Recession had on monetary policies has led to the profound reorientation of central banks’ actions from 2007 to 2013. The purpose of this work is to analyze the monetary policies applied by the main central banks, mainly the European Central Bank, the Federal Reserve System of USA and the Bank of Japan, in order to raise thoughts on the guidelines that central banks should follow in the future. In the first section the bases of monetary policy before the crisis are described; in the second we explain the change in the orientation of the role of central banks during the crisis; and finally, we synthesize the bases on which the economic debate is taking place on the orientation of future monetary policies. We conclude that, in so far as the inoperativeness of transmission mechanisms still persists, monetary policies will remain in a process of change.

  10. Oil and the geopolitics of Central Asia: A "new 'great game'"?

    Science.gov (United States)

    Al-Sati, Saud M.

    The nineteenth century rivalry between the Russian Empire and Great Britain over Central Asia, known as the "great game," was triggered by the quest for power and dominance. This study revisits Sir Halford Mackinder's thesis, which viewed the "heartland," consisting of Russia and Central Asia, as being crucial for international politics. It also discusses the influence of Mackinder's ideas on twentieth century geopolitical thinking. The study also examines the common assumption that the new "great game" in Central Asia is evolving around the exploitation of energy resources, and analyzes the consequences of this new factor for the geopolitical significance of the region. The landlocked nature of the Central Asian countries makes it necessary for them to rely on their neighbors for the export of oil and gas to international markets. Thus, the political and economic interests of Russia, Iran, and Turkey motivate them to compete with each other for export routes through their territories. This study also shows that the estimates of Central Asian proven oil reserves are characterized by considerable ambiguity. Estimates vary from seven to twenty-two billion barrels. Despite the fact that these proven oil reserves are limited compared to those of other regions, such as the Middle East, continued exploration is compatible with the Western strategy of energy resource diversification. Another primary aim of American involvement is to prevent the reintegration of Central Asia into the Russian federation and to block Chinese influence in Central Asia. This study reveals that realities in today's Central Asia are different from those of the nineteenth century. Central Asia now consists of independent countries; the competing powers have changed, with the exception of Russia; and oil has emerged as a new factor. However, the perpetual quest for power and dominance that marked the historical "great game" is still at work in the last decade of the twentieth century. Finally, the

  11. Cyanotoxins are not implicated in the etiology of coral black band disease outbreaks on Pelorus Island, Great Barrier Reef.

    Science.gov (United States)

    Glas, Martin S; Motti, Cherie A; Negri, Andrew P; Sato, Yui; Froscio, Suzanne; Humpage, Andrew R; Krock, Bernd; Cembella, Allan; Bourne, David G

    2010-07-01

    Cyanobacterial toxins (i.e. microcystins) produced within the microbial mat of coral black band disease (BBD) have been implicated in disease pathogenicity. This study investigated the presence of toxins within BBD lesions and other cyanobacterial patch (CP) lesions, which, in some instances ( approximately 19%), facilitated the onset of BBD, from an outbreak site at Pelorus Island on the inshore, central Great Barrier Reef (GBR). Cyanobacterial species that dominated the biomass of CP and BBD lesions were cultivated and identified, based on morphology and 16S rRNA gene sequences, as Blennothrix- and Oscillatoria-affiliated species, respectively, and identical to cyanobacterial sequences retrieved from previous molecular studies from this site. The presence of the cyanotoxins microcystin, cylindrospermopsin, saxitoxin, nodularin and anatoxin and their respective gene operons in field samples of CP and BBD lesions and their respective culture isolations was tested using genetic (PCR-based screenings), chemical (HPLC-UV, FTICR-MS and LC/MS(n)) and biochemical (PP2A) methods. Cyanotoxins and cyanotoxin synthetase genes were not detected in any of the samples. Cyanobacterial species dominant within CP and BBD lesions were phylogenetically distinct from species previously shown to produce cyanotoxins and isolated from BBD lesions. The results from this study demonstrate that cyanobacterial toxins appear to play no role in the pathogenicity of CP and BBD at this site on the GBR.

  12. Geographic and habitat partitioning of genetically distinct zooxanthellae (Symbiodinium) in Acropora corals on the Great Barrier Reef.

    Science.gov (United States)

    Ulstrup, K E; Van Oppen, M J H

    2003-12-01

    Intra- and intercolony diversity and distribution of zooxanthellae in acroporid corals is largely uncharted. In this study, two molecular methods were applied to determine the distribution of zooxanthellae in the branching corals Acropora tenuis and A. valida at several reef locations in the central section of the Great Barrier Reef. Sun-exposed and shaded parts of all colonies were examined. Single-stranded conformational polymorphism analysis showed that individual colonies of A. tenuis at two locations harbour two strains of Symbiodinium belonging to clade C (C1 and C2), whereas conspecific colonies at two other reefs harboured a single zooxanthella strain. A. valida was found to simultaneously harbour strains belonging to two distinct phylogenetic clades (C and D) at all locations sampled. A novel method with improved sensitivity (quantitative polymerase chain reaction using Taqman fluorogenic probes) was used to map the relative abundance distribution of the two zooxanthella clades. At two of the five sampling locations both coral species were collected. At these two locations, composition of the zooxanthella communities showed the same pattern in both coral species, i.e. correlation with ambient light in Pioneer Bay and an absence thereof in Nelly Bay. The results show that the distribution of genetically distinct zooxanthellae is correlated with light regime and possibly temperature in some (but not all) colonies of A. tenuis and A. valida and at some reef locations, which we interpret as acclimation to local environmental conditions.

  13. A decadal analysis of bioeroding sponge cover on the inshore Great Barrier Reef.

    Science.gov (United States)

    Ramsby, Blake D; Hoogenboom, Mia O; Whalan, Steve; Webster, Nicole S; Thompson, Angus

    2017-06-02

    Decreasing coral cover on the Great Barrier Reef (GBR) may provide opportunities for rapid growth and expansion of other taxa. The bioeroding sponges Cliona spp. are strong competitors for space and may take advantage of coral bleaching, damage, and mortality. Benthic surveys of the inshore GBR (2005-2014) revealed that the percent cover of the most abundant bioeroding sponge species, Cliona orientalis, has not increased. However, considerable variation in C. orientalis cover, and change in cover over time, was evident between survey locations. We assessed whether biotic or environmental characteristics were associated with variation in C. orientalis distribution and abundance. The proportion of fine particles in the sediments was negatively associated with the presence-absence and the percent cover of C. orientalis, indicating that the sponge requires exposed habitat. The cover of corals and other sponges explained little variation in C. orientalis cover or distribution. The fastest increases in C. orientalis cover coincided with the lowest macroalgal cover and chlorophyll a concentration, highlighting the importance of macroalgal competition and local environmental conditions for this bioeroding sponge. Given the observed distribution and habitat preferences of C. orientalis, bioeroding sponges likely represent site-specific - rather than regional - threats to corals and reef accretion.

  14. Avoiding Implementation Failure in Catchment Landscapes: A Case Study in Governance of the Great Barrier Reef.

    Science.gov (United States)

    Dale, Allan P; Vella, Karen; Gooch, Margaret; Potts, Ruth; Pressey, Robert L; Brodie, Jon; Eberhard, Rachel

    2017-10-04

    Water quality outcomes affecting Australia's Great Barrier Reef (GBR) are governed by multi-level and multi-party decision-making that influences forested and agricultural landscapes. With international concern about the GBR's declining ecological health, this paper identifies and focuses on implementation failure (primarily at catchment scale) as a systemic risk within the overall GBR governance system. There has been limited integrated analysis of the full suite of governance subdomains that often envelop defined policies, programs and delivery activities that influence water quality in the GBR. We consider how the implementation of separate purpose-specific policies and programs at catchment scale operate against well-known, robust design concepts for integrated catchment governance. We find design concerns within ten important governance subdomains that operate within GBR catchments. At a whole-of-GBR scale, we find a weak policy focus on strengthening these delivery-oriented subdomains and on effort integration across these subdomains within catchments. These governance problems when combined may contribute to failure in the implementation of major national, state and local government policies focused on improving water quality in the GBR, a lesson relevant to landscapes globally.

  15. MtDNA barcode identification of fish larvae in the southern Great Barrier Reef – Australia

    Directory of Open Access Journals (Sweden)

    Graham G. Pegg

    2006-10-01

    Full Text Available Planktonic larvae were captured above a shallow coral reef study site on the Great Barrier Reef (GBR around spring-summer new moon periods (October-February using light trap or net capture devices. Larvae were identified to the genus or species level by comparison with a phylogenetic tree of tropical marine fish species using mtDNA HVR1 sequence data. Further analysis showed that within-species HVR1 sequence variation was typically 1-3%, whereas between-species variation for the same genus ranged up to 50%, supporting the suitability of HVR1 for species identification. Given the current worldwide interest in DNA barcoding and species identification using an alternative mtDNA gene marker (cox1, we also explored the efficacy of different primer sets for amplification of cox1 in reef fish, and its suitability for species identification. Of those tested, the Fish-F1 and -R1 primer set recently reported by Ward et al. (2005 gave the best results.

  16. ENSO Weather and Coral Bleaching on the Great Barrier Reef, Australia

    Science.gov (United States)

    McGowan, Hamish; Theobald, Alison

    2017-10-01

    The most devastating mass coral bleaching has occurred during El Niño events, with bleaching reported to be a direct result of increased sea surface temperatures (SSTs). However, El Niño itself does not cause SSTs to rise in all regions that experience bleaching. Nor is the upper ocean warming trend of 0.11°C per decade since 1971, attributed to global warming, sufficient alone to exceed the thermal tolerance of corals. Here we show that weather patterns during El Niño that result in reduced cloud cover, higher than average air temperatures and higher than average atmospheric pressures, play a crucial role in determining the extent and location of coral bleaching on the world's largest coral reef system, the World Heritage Great Barrier Reef (GBR), Australia. Accordingly, synoptic-scale weather patterns and local atmosphere-ocean feedbacks related to El Niño-Southern Oscillation (ENSO) and not large-scale SST warming due to El Niño alone and/or global warming are often the cause of coral bleaching on the GBR.

  17. Structural and Psycho-Social Limits to Climate Change Adaptation in the Great Barrier Reef Region.

    Science.gov (United States)

    Evans, Louisa S; Hicks, Christina C; Adger, W Neil; Barnett, Jon; Perry, Allison L; Fidelman, Pedro; Tobin, Renae

    2016-01-01

    Adaptation, as a strategy to respond to climate change, has limits: there are conditions under which adaptation strategies fail to alleviate impacts from climate change. Research has primarily focused on identifying absolute bio-physical limits. This paper contributes empirical insight to an emerging literature on the social limits to adaptation. Such limits arise from the ways in which societies perceive, experience and respond to climate change. Using qualitative data from multi-stakeholder workshops and key-informant interviews with representatives of the fisheries and tourism sectors of the Great Barrier Reef region, we identify psycho-social and structural limits associated with key adaptation strategies, and examine how these are perceived as more or less absolute across levels of organisation. We find that actors experience social limits to adaptation when: i) the effort of pursuing a strategy exceeds the benefits of desired adaptation outcomes; ii) the particular strategy does not address the actual source of vulnerability, and; iii) the benefits derived from adaptation are undermined by external factors. We also find that social limits are not necessarily more absolute at higher levels of organisation: respondents perceived considerable opportunities to address some psycho-social limits at the national-international interface, while they considered some social limits at the local and regional levels to be effectively absolute.

  18. Towards environmental management of water turbidity within open coastal waters of the Great Barrier Reef.

    Science.gov (United States)

    Macdonald, Rachael K; Ridd, Peter V; Whinney, James C; Larcombe, Piers; Neil, David T

    2013-09-15

    Water turbidity and suspended sediment concentration (SSC) are commonly used as part of marine monitoring and water quality plans. Current management plans utilise threshold SSC values derived from mean-annual turbidity concentrations. Little published work documents typical ranges of turbidity for reefs within open coastal waters. Here, time-series turbidity measurements from 61 sites in the Great Barrier Reef (GBR) and Moreton Bay, Australia, are presented as turbidity exceedance curves and derivatives. This contributes to the understanding of turbidity and SSC in the context of environmental management in open-coastal reef environments. Exceedance results indicate strong spatial and temporal variability in water turbidity across inter/intraregional scales. The highest turbidity across 61 sites, at 50% exceedance (T50) is 15.3 NTU and at 90% exceedance (T90) 4.1 NTU. Mean/median turbidity comparisons show strong differences between the two, consistent with a strongly skewed turbidity regime. Results may contribute towards promoting refinement of water quality management protocols. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Library Anxiety As A Great Barrier Before Effective Library Use: A General Appraisal

    Directory of Open Access Journals (Sweden)

    Erol Yılmaz

    2011-09-01

    Full Text Available Library anxiety is a subject which has been searched in international platform in its various dimensions since 1986 in which the concept was first defined. On the other hand, this important subject, in the context of this article, as of the end of 2010 year in which we concluded literature survey, has never been handled and studied on in the scope of Turkish Librarianship.2 Main purpose of this study which is the first article in which library anxiety is studied as an independent subject in the scope of Turkish Librarianship is to draw attention to the subject of library anxiety which is a great barrier for the users before the high level satisfaction relating to the library services, who are the existence reason of the libraries andfurthermore is to handle the studies prepared in the past on this subject under a general approach. Furthermore in this study, studies close to the subject in the Turkish Librarianship were handled and a general appraisal was made on the subject. At the final part of the study, place was given to some proposals which are directed towards the discussion of library anxiety in theoretical dimension within the scope of Turkish Librarianship and furthermore some proposals which are aimed to prevent and eliminate the formation of library anxiety in the users during the application (operation of the library are given place.

  20. Unique Sequence of Events Triggers Manta Ray Feeding Frenzy in the Southern Great Barrier Reef, Australia

    Directory of Open Access Journals (Sweden)

    Scarla J. Weeks

    2015-03-01

    Full Text Available Manta rays are classified as Vulnerable to Extinction on the IUCN Red List for Threatened Species. In Australia, a key aggregation site for reef manta rays is Lady Elliot Island (LEI on the Great Barrier Reef, ~7 km from the shelf edge. Here, we investigate the environmental processes that triggered the largest manta ray feeding aggregation yet observed in Australia, in early 2013. We use MODIS sea surface temperature (SST, chlorophyll-a concentration and photic depth data, together with in situ data, to show that anomalous river discharges led to high chlorophyll (anomalies: 10–15 mg∙m−3 and turbid (photic depth anomalies: −15 m river plumes extending out to LEI, and that these became entrained offshore around the periphery of an active cyclonic eddy. Eddy dynamics led to cold bottom intrusions along the shelf edge (6 °C temperature decrease, and at LEI (5 °C temperature decrease. Strongest SST gradients (>1 °C∙km−1 were at the convergent frontal zone between the shelf and eddy-influenced waters, directly overlying LEI. Here, the front intensified on the spring ebb tide to attract and shape the aggregation pattern of foraging manta rays. Future research could focus on mapping the probability and persistence of these ecologically significant frontal zones via remote sensing to aid the management and conservation of marine species.

  1. Structural and Psycho-Social Limits to Climate Change Adaptation in the Great Barrier Reef Region.

    Directory of Open Access Journals (Sweden)

    Louisa S Evans

    Full Text Available Adaptation, as a strategy to respond to climate change, has limits: there are conditions under which adaptation strategies fail to alleviate impacts from climate change. Research has primarily focused on identifying absolute bio-physical limits. This paper contributes empirical insight to an emerging literature on the social limits to adaptation. Such limits arise from the ways in which societies perceive, experience and respond to climate change. Using qualitative data from multi-stakeholder workshops and key-informant interviews with representatives of the fisheries and tourism sectors of the Great Barrier Reef region, we identify psycho-social and structural limits associated with key adaptation strategies, and examine how these are perceived as more or less absolute across levels of organisation. We find that actors experience social limits to adaptation when: i the effort of pursuing a strategy exceeds the benefits of desired adaptation outcomes; ii the particular strategy does not address the actual source of vulnerability, and; iii the benefits derived from adaptation are undermined by external factors. We also find that social limits are not necessarily more absolute at higher levels of organisation: respondents perceived considerable opportunities to address some psycho-social limits at the national-international interface, while they considered some social limits at the local and regional levels to be effectively absolute.

  2. Understanding Biophysical Interactions In The Great Barrier Reef Catchments: Better Landscape Management For Water Quality Outcomes

    Science.gov (United States)

    Bui, E. N.; Wilkinson, S. N.; Bartley, R.

    2014-12-01

    Sediment input to the Great Barrier Reef (GBR) lagoon has had deleterious impacts on seagrass and coral ecosystems. The response of the Australian government has been to develop policies to: (i) reverse the impact of threats from sediments and nutrients, and improve water quality and aquatic health of the GBR lagoon; and (ii) to facilitate the uptake of sustainable farming and land management practices that deliver improved ecosystem services, by at least 30 per cent of farmers. The Reef2050 Long term sustainability plan aims to identify priority locations for on-ground investment of remediation options that will result in a reduction of constituent loads to the GBR. Recent sediment tracing studies indicate that subsoil from erosion features such as gullies and channel banks are the dominant contributors of sediment in the GBR catchments. Better control of gully and streambank erosion and restoration of riparian habitats are therefore necessary. Here we review the evidence for bank erosion in the GBR catchments and how scientific evidence on feedback relationships between climate- geochemistry-vegetation-landforms can be used to develop better guidelines for streambank and gully re-vegetation.

  3. Diversity and Activity of Diazotrophs in Great Barrier Reef Surface Waters.

    Science.gov (United States)

    Messer, Lauren F; Brown, Mark V; Furnas, Miles J; Carney, Richard L; McKinnon, A D; Seymour, Justin R

    2017-01-01

    Discrepancies between bioavailable nitrogen (N) concentrations and phytoplankton growth rates in the oligotrophic waters of the Great Barrier Reef (GBR) suggest that undetermined N sources must play a significant role in supporting primary productivity. One such source could be biological dinitrogen (N 2 ) fixation through the activity of "diazotrophic" bacterioplankton. Here, we investigated N 2 fixation and diazotroph community composition over 10° S of latitude within GBR surface waters. Qualitative N 2 fixation rates were found to be variable across the GBR but were relatively high in coastal, inner and outer GBR waters, reaching 68 nmol L -1 d -1 . Diazotroph assemblages, identified by amplicon sequencing of the nifH gene, were dominated by the cyanobacterium Trichodesmium erythraeum , γ-proteobacteria from the Gamma A clade, and δ-proteobacterial phylotypes related to sulfate-reducing genera. However, diazotroph communities exhibited significant spatial heterogeneity, correlated with shifts in dissolved inorganic nutrient concentrations. Specifically, heterotrophic diazotrophs generally increased in relative abundance with increasing concentrations of phosphate and N, while Trichodesmium was proportionally more abundant when concentrations of these nutrients were low. This study provides the first in-depth characterization of diazotroph community composition and N 2 fixation dynamics within the oligotrophic, N-limited surface waters of the GBR. Our observations highlight the need to re-evaluate N cycling dynamics within oligotrophic coral reef systems, to include diverse N 2 fixing assemblages as a potentially significant source of dissolved N within the water column.

  4. Palynology, sedimentology and environmental significance of Holocene swamps at northern Kaitoke, Great Barrier Island, New Zealand

    International Nuclear Information System (INIS)

    Horrocks, M.; Ogden, J.; Nichol, S.L.; Alloway, B.V.; Sutton, D.G.

    2000-01-01

    Pollen and sediment analyses of two cores from coastal freshwater swamps at northern Kaitoke (Kaitoke Swamp and Police Station Swamp), Great Barrier Island, show that c. 7300 calibrated yr BP Kaitoke Swamp was an estuary with tidal flats. Avicennia, now absent from the swamp area, was present in the estuary. By c. 4500 yr BP fresh water conditions had developed at the Kaitoke Swamp site as marine influences decreased. Around the same time, fresh water swamp conditions commenced at the Police Station Swamp site on the surface of a low lying area of a Late Pleistocene dune. A sandy layer at Kaitoke may represent rapid infilling followed by a dry soil surface until c. 1000 yr BP. Conifer-hardwood forest on the hills surrounding the sites c. 7300-c. 1800 yr BP was dominated by Dacrydium and Metrosideros. During this period, environmental conditions were relatively stable, with little change in forest composition. Between 1800 yr and 800 yr BP Kaitoke Swamp was reflooded, and the Police Station Swamp extended as a shallow lake over the nearby dune flat. These new shallow swamps were invaded by swamp forest (mainly Dacrycaprus with some Laurelia). The presence of charcoal and Pteridium spores above the Kaharoa Tephra suggests that major Polynesian deforestation at northern Kaitoke began c. 600 calibrated yr BP. (author). 41 refs., 4 figs., 2 tabs

  5. A method for risk analysis across governance systems: a Great Barrier Reef case study

    International Nuclear Information System (INIS)

    Dale, Allan; Vella, Karen; Potts, Ruth; Pressey, Robert L; Brodie, Jon; Yorkston, Hugh

    2013-01-01

    Healthy governance systems are key to delivering sound environmental management outcomes from global to local scales. There are, however, surprisingly few risk assessment methods that can pinpoint those domains and sub-domains within governance systems that are most likely to influence good environmental outcomes at any particular scale, or those if absent or dysfunctional, most likely to prevent effective environmental management. This paper proposes a new risk assessment method for analysing governance systems. This method is then tested through its preliminary application to a significant real-world context: governance as it relates to the health of Australia’s Great Barrier Reef (GBR). The GBR exists at a supra-regional scale along most of the north eastern coast of Australia. Brodie et al (2012 Mar. Pollut. Bull. 65 81–100) have recently reviewed the state and trend of the health of the GBR, finding that overall trends remain of significant concern. At the same time, official international concern over the governance of the reef has recently been signalled globally by the International Union for the Conservation of Nature (IUCN). These environmental and political contexts make the GBR an ideal candidate for use in testing and reviewing the application of improved tools for governance risk assessment. (letter)

  6. Dispersal of adult black marlin (Istiompax indica from a Great Barrier Reef spawning aggregation.

    Directory of Open Access Journals (Sweden)

    Michael L Domeier

    Full Text Available The black marlin (Istiompax indica is one of the largest bony fishes in the world with females capable of reaching a mass of over 700 kg. This highly migratory predator occurs in the tropical regions of the Pacific and Indian Oceans, and is the target of regional recreational and commercial fisheries. Through the sampling of ichthyoplankton and ovaries we provide evidence that the relatively high seasonal abundance of black marlin off the Great Barrier Reef is, in fact, a spawning aggregation. Furthermore, through the tracking of individual black marlin via satellite popup tags, we document the dispersal of adult black marlin away from the spawning aggregation, thereby identifying the catchment area for this spawning stock. Although tag shedding is an issue when studying billfish, we tentatively identify the catchment area for this stock of black marlin to extend throughout the Coral Sea, including the waters of Papua New Guinea, the Solomon Islands, Micronesia, New Caledonia, Kiribati, Vanuatu, Fiji, Tuvalu and Nauru.

  7. Ocean acidification: Linking science to management solutions using the Great Barrier Reef as a case study.

    Science.gov (United States)

    Albright, Rebecca; Anthony, Kenneth R N; Baird, Mark; Beeden, Roger; Byrne, Maria; Collier, Catherine; Dove, Sophie; Fabricius, Katharina; Hoegh-Guldberg, Ove; Kelly, Ryan P; Lough, Janice; Mongin, Mathieu; Munday, Philip L; Pears, Rachel J; Russell, Bayden D; Tilbrook, Bronte; Abal, Eva

    2016-11-01

    Coral reefs are one of the most vulnerable ecosystems to ocean acidification. While our understanding of the potential impacts of ocean acidification on coral reef ecosystems is growing, gaps remain that limit our ability to translate scientific knowledge into management action. To guide solution-based research, we review the current knowledge of ocean acidification impacts on coral reefs alongside management needs and priorities. We use the world's largest continuous reef system, Australia's Great Barrier Reef (GBR), as a case study. We integrate scientific knowledge gained from a variety of approaches (e.g., laboratory studies, field observations, and ecosystem modelling) and scales (e.g., cell, organism, ecosystem) that underpin a systems-level understanding of how ocean acidification is likely to impact the GBR and associated goods and services. We then discuss local and regional management options that may be effective to help mitigate the effects of ocean acidification on the GBR, with likely application to other coral reef systems. We develop a research framework for linking solution-based ocean acidification research to practical management options. The framework assists in identifying effective and cost-efficient options for supporting ecosystem resilience. The framework enables on-the-ground OA management to be the focus, while not losing sight of CO2 mitigation as the ultimate solution. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Understanding Recreational Fishers' Compliance with No-take Zones in the Great Barrier Reef Marine Park

    Directory of Open Access Journals (Sweden)

    Adrian Arias

    2013-12-01

    Full Text Available Understanding fishers' compliance is essential for the successful management of marine protected areas. We used the random response technique (RRT to assess recreational fishers' compliance with no-take zones in the Great Barrier Reef Marine Park (GBRMP. The RRT allowed the asking of a sensitive question, i.e., "Did you, knowingly, fish within in a Green Zone during the last 12 months?" while protecting respondents' confidentiality. Application of the RRT through a survey of recreational fishers indicated that the majority of recreational fishers, 90%, comply with no-take zones. Likewise, most fishers, 92%, reported not personally knowing anyone who had intentionally fished in a no-take zone, indicating that fishers' perceive high levels of compliance among their peers. Fishers were motivated to comply with no-take zones primarily by their beliefs about penalties for noncompliance, followed by beliefs about the fishery benefits of no-take zones. Results suggest that compliance-related communication efforts by the managing authority have partially succeeded in maintaining appropriate compliance levels and that future efforts should accentuate normative compliance drivers that will encourage voluntary compliance. We conclude that compliance monitoring should be integrated into the adaptive management of the GBRMP and other protected areas; in this case social surveys using the RRT are effective tools.

  9. The distribution and abundance of reef-associated predatory fishes on the Great Barrier Reef

    Science.gov (United States)

    Emslie, Michael J.; Cheal, Alistair J.; Logan, Murray

    2017-09-01

    Predatory fishes are important components of coral-reef ecosystems of the Great Barrier Reef (GBR) through both the ecological functions they perform and their high value to recreational and commercial fisheries, estimated at 30 million in 2014. However, management of GBR predatory fish populations is hampered by a lack of knowledge of their distribution and abundance, aside from that of the highly targeted coral trout ( Plectropomus spp. and Variola spp.). Furthermore, there is little information on how these fishes respond to environmental stressors such as coral bleaching, outbreaks of coral-feeding starfishes ( Acanthaster planci) and storms, which limits adaptive management of their populations as the frequency or severity of such natural disturbances increases under climate change. Here, we document the distribution and abundance of 48 species of reef-associated predatory fishes and assess their vulnerability to a range of natural disturbances. There were clear differences in predatory fish assemblages across the continental shelf, but many species were widespread, with few species restricted to either inshore or offshore waters. There was weak latitudinal structure with only a few species restricted to either the northern or southern GBR. On the whole, predatory fishes were surprisingly resistant to the effects of disturbance, with few clear changes in abundance or species richness following 66 documented disturbances of varying magnitudes.

  10. [The blood-brain barrier and drug delivery in the central nervous system].

    Science.gov (United States)

    Loch-Neckel, Gecioni; Koepp, Janice

    2010-08-01

    To provide an updated view of the difficulties due to barriers and strategies used to allow the release of drugs in the central nervous system. The difficulty for the treatment of many diseases of the central nervous system, through the use of intra-venous drugs, is due to the presence of barriers that prevent the release of the same: the blood-brain barrier, blood-cerebro-spinal fluid barrier and the blood-arachnoid barrier. The blood-brain barrier is the main barrier for the transport of drugs in the brain that also acts as a immunologic and metabolic barrier. The endothelial cells of the blood-brain barrier are connected to a junction complex through the interaction of transmembrane proteins that protrude from de inside to the outside, forming a connection between the endothelial cells. The transport of substances to the brain depends on the mechanisms of transport present in the barrier and the diffusion of these compounds also depends on the physicochemical characteristics of the molecule. Some diseases alter the permeability of the blood-brain barrier and thus the passage of drugs. Strategies such as the use of methods for drug delivery in the brain have been investigated. Further details regarding the mechanisms of transport across the blood-brain barrier and the changes in neuropathology would provide important information about the etiology of diseases and lead to better therapeutic strategies.

  11. Do clouds save the great barrier reef? satellite imagery elucidates the cloud-SST relationship at the local scale.

    Directory of Open Access Journals (Sweden)

    Susannah M Leahy

    Full Text Available Evidence of global climate change and rising sea surface temperatures (SSTs is now well documented in the scientific literature. With corals already living close to their thermal maxima, increases in SSTs are of great concern for the survival of coral reefs. Cloud feedback processes may have the potential to constrain SSTs, serving to enforce an "ocean thermostat" and promoting the survival of coral reefs. In this study, it was hypothesized that cloud cover can affect summer SSTs in the tropics. Detailed direct and lagged relationships between cloud cover and SST across the central Great Barrier Reef (GBR shelf were investigated using data from satellite imagery and in situ temperature and light loggers during two relatively hot summers (2005 and 2006 and two relatively cool summers (2007 and 2008. Across all study summers and shelf positions, SSTs exhibited distinct drops during periods of high cloud cover, and conversely, SST increases during periods of low cloud cover, with a three-day temporal lag between a change in cloud cover and a subsequent change in SST. Cloud cover alone was responsible for up to 32.1% of the variation in SSTs three days later. The relationship was strongest in both El Niño (2005 and La Niña (2008 study summers and at the inner-shelf position in those summers. SST effects on subsequent cloud cover were weaker and more variable among study summers, with rising SSTs explaining up to 21.6% of the increase in cloud cover three days later. This work quantifies the often observed cloud cooling effect on coral reefs. It highlights the importance of incorporating local-scale processes into bleaching forecasting models, and encourages the use of remote sensing imagery to value-add to coral bleaching field studies and to more accurately predict risks to coral reefs.

  12. The Gulf of Carpentaria heated Torres Strait and the Northern Great Barrier Reef during the 2016 mass coral bleaching event

    NARCIS (Netherlands)

    Wolanski, E.; Andutta, Fernando P.; Deleersnijder, E.L.C.; Li, Y.; Thomas, C.J.

    The 2015/16 ENSO event increased the temperature of waters surrounding northeast Australia to above 30 °C, with large patches of water reaching 32 °C, for over two months, which led to severe bleaching of corals of the Northern Great Barrier Reef (NGBR). This study provides evidence gained from

  13. Diuron tolerance and potential degradation by pelagic microbiomes in the Great Barrier Reef lagoon

    Directory of Open Access Journals (Sweden)

    Florent E. Angly

    2016-03-01

    Full Text Available Diuron is a herbicide commonly used in agricultural areas where excess application causes it to leach into rivers, reach sensitive marine environments like the Great Barrier Reef (GBR lagoon and pose risks to marine life. To investigate the impact of diuron on whole prokaryotic communities that underpin the marine food web and are integral to coral reef health, GBR lagoon water was incubated with diuron at environmentally-relevant concentration (8 µg/L, and sequenced at specific time points over the following year. 16S rRNA gene amplicon profiling revealed no significant short- or long-term effect of diuron on microbiome structure. The relative abundance of prokaryotic phototrophs was not significantly altered by diuron, which suggests that they were largely tolerant at this concentration. Assembly of a metagenome derived from waters sampled at a similar location in the GBR lagoon did not reveal the presence of mutations in the cyanobacterial photosystem that could explain diuron tolerance. However, resident phages displayed several variants of this gene and could potentially play a role in tolerance acquisition. Slow biodegradation of diuron was reported in the incubation flasks, but no correlation with the relative abundance of heterotrophs was evident. Analysis of metagenomic reads supports the hypothesis that previously uncharacterized hydrolases carried by low-abundance species may mediate herbicide degradation in the GBR lagoon. Overall, this study offers evidence that pelagic phototrophs of the GBR lagoon may be more tolerant of diuron than other tropical organisms, and that heterotrophs in the microbial seed bank may have the potential to degrade diuron and alleviate local anthropogenic stresses to inshore GBR ecosystems.

  14. Surviving coral bleaching events: porites growth anomalies on the Great Barrier Reef.

    Science.gov (United States)

    Cantin, Neal E; Lough, Janice M

    2014-01-01

    Mass coral bleaching affected large parts of the Great Barrier Reef (GBR) in 1998 and 2002. In this study, we assessed if signatures of these major thermal stress events were recorded in the growth characteristics of massive Porites colonies. In 2005 a suite of short (bleaching. Sites included inshore (Nelly Bay, Pandora Reef), annually affected by freshwater flood events, midshelf (Rib Reef), only occasionally affected by freshwater floods and offshore (Myrmidon Reef) locations primarily exposed to open ocean conditions. Annual growth characteristics (extension, density and calcification) were measured in 144 cores from 79 coral colonies and analysed over the common 24-year period, 1980-2003. Visual examination of the annual density bands revealed growth hiatuses associated with the bleaching years in the form of abrupt decreases in annual linear extension rates, high density stress bands and partial mortality. The 1998 mass-bleaching event reduced Porites calcification by 13 and 18% on the two inshore locations for 4 years, followed by recovery to baseline calcification rates in 2002. Evidence of partial mortality was apparent in 10% of the offshore colonies in 2002; however no significant effects of the bleaching events were evident in the calcification rates at the mid shelf and offshore sites. These results highlight the spatial variation of mass bleaching events and that all reef locations within the GBR were not equally stressed by the 1998 and 2002 mass bleaching events, as some models tend to suggest, which enabled recovery of calcification on the GBR within 4 years. The dynamics in annual calcification rates and recovery displayed here should be used to improve model outputs that project how coral calcification will respond to ongoing warming of the tropical oceans.

  15. Elevated land runoff after European settlement perturbs persistent foraminiferal assemblages on the Great Barrier Reef.

    Science.gov (United States)

    Uthicke, S; Patel, F; Ditchburn, R

    2012-01-01

    Coral reefs are under pressure from a variety of human-induced disturbances, but demonstration of ecosystem changes and identification of stressors are often difficult. We tested whether global change or increased agricultural runoff after European settlement of Northeast Australia (ca. 1860) has affected inshore reefs of the Great Barrier Reef. Eleven sediment cores were retrieved from inner reefs, intermediate reefs, and outer-island reefs, and benthic foraminiferal assemblages were analyzed in dated (14C, 210Pb, 137Cs) core sections (N = 82 samples). Data were grouped into six age bands ( 1500 yr). Principal component analysis and two-factor (Zone and Age) permutational analysis of variance (PERMANOVA) suggested that assemblages from the three zones were significantly different from each other over several millennia, with symbiont-bearing (mixotrophic) species dominating the outer reefs. A significant interaction term indicated that within-zone patterns varied. Assemblages in outer reefs unaffected from increased land runoff were persistent until present times. In both other zones, assemblages were also persistent until 150 yr ago, suggesting that benthic foraminiferal assemblages are naturally highly persistent over long (> 2000 yr) timescales. Assemblages in core sections PERMANOVA. With some exceptions, changes on the inner and intermediate reefs were consistent with a model predicting that increased nutrients and higher turbidity enhance relative abundance of heterotrophic species. Given that assemblages did not change in outer-island reefs (not impacted by runoff) we argue that changes in assemblages due to global change can be rejected as an explanation. Thus, the findings are more consistent with the hypothesis that agricultural runoff since European settlement altered foraminiferal assemblages than with the hypothesis that global forcing caused changes.

  16. Diuron tolerance and potential degradation by pelagic microbiomes in the Great Barrier Reef lagoon

    Science.gov (United States)

    Pantos, Olga; Morgan, Thomas C.; Rich, Virginia; Tonin, Hemerson; Bourne, David G.; Mercurio, Philip; Negri, Andrew P.; Tyson, Gene W.

    2016-01-01

    Diuron is a herbicide commonly used in agricultural areas where excess application causes it to leach into rivers, reach sensitive marine environments like the Great Barrier Reef (GBR) lagoon and pose risks to marine life. To investigate the impact of diuron on whole prokaryotic communities that underpin the marine food web and are integral to coral reef health, GBR lagoon water was incubated with diuron at environmentally-relevant concentration (8 µg/L), and sequenced at specific time points over the following year. 16S rRNA gene amplicon profiling revealed no significant short- or long-term effect of diuron on microbiome structure. The relative abundance of prokaryotic phototrophs was not significantly altered by diuron, which suggests that they were largely tolerant at this concentration. Assembly of a metagenome derived from waters sampled at a similar location in the GBR lagoon did not reveal the presence of mutations in the cyanobacterial photosystem that could explain diuron tolerance. However, resident phages displayed several variants of this gene and could potentially play a role in tolerance acquisition. Slow biodegradation of diuron was reported in the incubation flasks, but no correlation with the relative abundance of heterotrophs was evident. Analysis of metagenomic reads supports the hypothesis that previously uncharacterized hydrolases carried by low-abundance species may mediate herbicide degradation in the GBR lagoon. Overall, this study offers evidence that pelagic phototrophs of the GBR lagoon may be more tolerant of diuron than other tropical organisms, and that heterotrophs in the microbial seed bank may have the potential to degrade diuron and alleviate local anthropogenic stresses to inshore GBR ecosystems. PMID:26989611

  17. Diuron tolerance and potential degradation by pelagic microbiomes in the Great Barrier Reef lagoon.

    Science.gov (United States)

    Angly, Florent E; Pantos, Olga; Morgan, Thomas C; Rich, Virginia; Tonin, Hemerson; Bourne, David G; Mercurio, Philip; Negri, Andrew P; Tyson, Gene W

    2016-01-01

    Diuron is a herbicide commonly used in agricultural areas where excess application causes it to leach into rivers, reach sensitive marine environments like the Great Barrier Reef (GBR) lagoon and pose risks to marine life. To investigate the impact of diuron on whole prokaryotic communities that underpin the marine food web and are integral to coral reef health, GBR lagoon water was incubated with diuron at environmentally-relevant concentration (8 µg/L), and sequenced at specific time points over the following year. 16S rRNA gene amplicon profiling revealed no significant short- or long-term effect of diuron on microbiome structure. The relative abundance of prokaryotic phototrophs was not significantly altered by diuron, which suggests that they were largely tolerant at this concentration. Assembly of a metagenome derived from waters sampled at a similar location in the GBR lagoon did not reveal the presence of mutations in the cyanobacterial photosystem that could explain diuron tolerance. However, resident phages displayed several variants of this gene and could potentially play a role in tolerance acquisition. Slow biodegradation of diuron was reported in the incubation flasks, but no correlation with the relative abundance of heterotrophs was evident. Analysis of metagenomic reads supports the hypothesis that previously uncharacterized hydrolases carried by low-abundance species may mediate herbicide degradation in the GBR lagoon. Overall, this study offers evidence that pelagic phototrophs of the GBR lagoon may be more tolerant of diuron than other tropical organisms, and that heterotrophs in the microbial seed bank may have the potential to degrade diuron and alleviate local anthropogenic stresses to inshore GBR ecosystems.

  18. In the other 90%: phytoplankton responses to enhanced nutrient availability in the Great Barrier Reef Lagoon

    International Nuclear Information System (INIS)

    Furnas, Miles; Mitchell, Alan; Skuza, Michele; Brodie, Jon

    2005-01-01

    Our view of how water quality effects ecosystems of the Great Barrier Reef (GBR) is largely framed by observed or expected responses of large benthic organisms (corals, algae, seagrasses) to enhanced levels of dissolved nutrients, sediments and other pollutants in reef waters. In the case of nutrients, however, benthic organisms and communities are largely responding to materials which have cycled through and been transformed by pelagic communities dominated by micro-algae (phytoplankton), protozoa, flagellates and bacteria. Because GBR waters are characterised by high ambient light intensities and water temperatures, inputs of nutrients from both internal and external sources are rapidly taken up and converted to organic matter in inter-reefal waters. Phytoplankton growth, pelagic grazing and remineralisation rates are very rapid. Dominant phytoplankton species in GBR waters have in situ growth rates which range from ∼1 to several doublings per day. To a first approximation, phytoplankton communities and their constituent nutrient content turn over on a daily basis. Relative abundances of dissolved nutrient species strongly indicate N limitation of new biomass formation. Direct ( 15 N) and indirect ( 14 C) estimates of N demand by phytoplankton indicate dissolved inorganic N pools have turnover times on the order of hours to days. Turnover times for inorganic phosphorus in the water column range from hours to weeks. Because of the rapid assimilation of nutrients by plankton communities, biological responses in benthic communities to changed water quality are more likely driven (at several ecological levels) by organic matter derived from pelagic primary production than by dissolved nutrient stocks alone

  19. Benthic Foraminifera as ecological indicators for water quality on the Great Barrier Reef

    Science.gov (United States)

    Uthicke, Sven; Nobes, Kristie

    2008-07-01

    Benthic foraminifera are established indicators for Water Quality (WQ) in Florida and the Caribbean. However, nearshore coral reefs of the Great Barrier Reef (GBR) and other Pacific regions are also subjected to increased nutrient and sediment loads. Here, we investigate the use of benthic foraminifera as indicators to assess status and trends of WQ on GBR reefs. We quantified several sediment parameters and the foraminiferan assemblage composition on 20 reefs in four geographic regions of the GBR, and along a water column nutrient and turbidity gradient. Twenty-seven easily recognisable benthic foraminiferan taxa (>63 μm) were distinguished. All four geographic regions differed significantly ( p turbid inner shelf towards clearer outer shelf reefs. A RDA separated symbiotic and aposymbiotic (heterotrophic) taxa. In addition, total suspended solid and water column chlorophyll a concentrations were negatively correlated, and optical depth and distance to the mainland were positively correlated, with the abundance of symbiont-bearing taxa. Several large foraminifera were identified as indicators for offshore, clear water conditions. In contrast, heterotrophic rotaliids and a species retaining plastids ( Elphidium sp.) where highly characteristic for low light, higher nutrient conditions. Application of the FORAM index to GBR assemblage composition showed a significant increase in the value of this index with increased distance from the mainland in the Whitsunday region ( r2 = 0.75, p < 0.001), and therefore with increasing light and decreased nutrient availability. We conclude that it will be possible to apply this index to GBR and possibly other Pacific reefs after some adaptations and additional experimental work on species-specific limiting factors.

  20. Social Resilience and Commercial Fishers' Responses to Management Changes in the Great Barrier Reef Marine Park

    Directory of Open Access Journals (Sweden)

    Stephen G. Sutton

    2012-09-01

    Full Text Available Understanding how social resilience influences resource users' responses to policy change is important for ensuring the sustainability of social-ecological systems and resource-dependent communities. We use the conceptualization and operationalization of social resilience proposed by Marshall and Marshall (2007 to investigate how resilience level influenced commercial fishers' perceptions about and adaptation to the 2004 rezoning of the Great Barrier Reef Marine Park. We conducted face-to-face interviews with 114 commercial and charter fishers to measure their social resilience level and their responses and adaptation strategies to the 2004 zoning plan. Fishers with higher resilience were more likely to believe that the zoning plan was necessary, more likely to be supportive of the plan, and more likely to have adapted their fishing business and fishing activity to the plan than were fishers with lower social resilience. High-resilience fishers were also less likely to perceive negative impacts of the plan on their fishing business, less likely to have negative attitudes toward the consultation process used to develop and implement the plan, and less likely to have applied for financial compensation under the structural adjustment program. Results confirm the utility of the social resilience construct for identifying fishers who are likely to be vulnerable to changes, and those who are struggling to cope with change events. We conclude that managing for social resilience in the GBR would aid in the design and implementation of policies that minimize the impacts on resource users and lead to more inclusive and sustainable management, but that further research is necessary to better understand social resilience, how it can be fostered and sustained, and how it can be effectively incorporated into management.

  1. Spatiotemporal patterns of coral disease prevalence on Heron Island, Great Barrier Reef, Australia

    Science.gov (United States)

    Haapkylä, J.; Melbourne-Thomas, J.; Flavell, M.; Willis, B. L.

    2010-12-01

    Despite increasing research effort on coral diseases, little is known about factors driving disease dynamics on the Great Barrier Reef (GBR). This is the first study to investigate the temporal patterns of coral disease prevalence and potential drivers of disease around Heron Island, in the southern Capricorn Bunker sector of the GBR. Surveys were conducted in two austral summers and three winters between November 2007 and August 2009 on six sites around the island. Six diseases were detected: brown band syndrome (BrB), growth anomalies (GA), ulcerative white spots (UWS), white syndrome (WS), skeletal eroding band disease (SEB) and black band disease (BBD). The lowest overall mean disease prevalence was 1.87 ± 0.75% (mean ± SE) in November 2007 and the highest 4.22 ± 1.72% in August 2008. There was evidence of seasonality for two diseases: BrB and UWS. This is the first study to report a higher prevalence of BrB in the winter. BrB had a prevalence of 3.29 ± 0.58% in August 2008 and 1.53 ± 0.28% in August 2009, while UWS was the most common syndrome in the summer with a prevalence of 1.12 ± 0.31% in November 2007 and 2.67 ± 0.52% prevalence in January 2008. The prevalence of GAs and SEB did not depend on the season, although the prevalence of GAs increased throughout the study period. WS had a slightly higher prevalence in the summer, but its overall prevalence was low (disease prevalence (12% of Acropora and 3.3% of Montipora species were diseased respectively). These results highlight the correlations between coral disease prevalence, seasonally varying environmental parameters and coral community composition. Given that diseases are likely to reduce the resilience of corals, seasonal patterns in disease prevalence deserve further research.

  2. Modelling the fate of marine debris along a complex shoreline: Lessons from the Great Barrier Reef

    Science.gov (United States)

    Critchell, K.; Grech, A.; Schlaefer, J.; Andutta, F. P.; Lambrechts, J.; Wolanski, E.; Hamann, M.

    2015-12-01

    The accumulation of floating anthropogenic debris in marine and coastal areas has environmental, economic, aesthetic, and human health impacts. Until now, modelling the transport of such debris has largely been restricted to the large-scales of open seas. We used oceanographic modelling to identify potential sites of debris accumulation along a rugged coastline with headlands, islands, rocky coasts and beaches. Our study site was the Great Barrier Reef World Heritage Area that has an emerging problem with debris accumulation. We found that the classical techniques of modelling the transport of floating debris models are only moderately successful due to a number of unknowns or assumptions, such as the value of the wind drift coefficient, the variability of the oceanic forcing and of the wind, the resuspension of some floating debris by waves, and the poorly known relative contribution of floating debris from urban rivers and commercial and recreational shipping. Nevertheless the model was successful in reproducing a number of observations such as the existence of hot spots of accumulation. The orientation of beaches to the prevailing wind direction affected the accumulation rate of debris. The wind drift coefficient and the exact timing of the release of the debris at sea affected little the movement of debris originating from rivers but it affected measurably that of debris originating from ships. It was thus possible to produce local hotspot maps for floating debris, especially those originating from rivers. Such modelling can be used to inform local management decisions, and it also identifies likely priority research areas to more reliably predict the trajectory and landing points of floating debris.

  3. The 1985 central chile earthquake: a repeat of previous great earthquakes in the region?

    Science.gov (United States)

    Comte, D; Eisenberg, A; Lorca, E; Pardo, M; Ponce, L; Saragoni, R; Singh, S K; Suárez, G

    1986-07-25

    A great earthquake (surface-wave magnitude, 7.8) occurred along the coast of central Chile on 3 March 1985, causing heavy damage to coastal towns. Intense foreshock activity near the epicenter of the main shock occurred for 11 days before the earthquake. The aftershocks of the 1985 earthquake define a rupture area of 170 by 110 square kilometers. The earthquake was forecast on the basis of the nearly constant repeat time (83 +/- 9 years) of great earthquakes in this region. An analysis of previous earthquakes suggests that the rupture lengths of great shocks in the region vary by a factor of about 3. The nearly constant repeat time and variable rupture lengths cannot be reconciled with time- or slip-predictable models of earthquake recurrence. The great earthquakes in the region seem to involve a variable rupture mode and yet, for unknown reasons, remain periodic. Historical data suggest that the region south of the 1985 rupture zone should now be considered a gap of high seismic potential that may rupture in a great earthquake in the next few tens of years.

  4. Utility of Photochemical Traits as Diagnostics of Thermal Tolerance amongst Great Barrier Reef Corals

    Directory of Open Access Journals (Sweden)

    Matthew R. Nitschke

    2018-02-01

    Full Text Available Light availability is considered a key factor regulating the thermal sensitivity of reef building corals, where excessive excitation of photosystem II (PSII further exacerbates pressure on photochemical pathways already compromised by heat stress. Coral symbionts acclimate to changes in light availability (photoacclimation by continually fine-tuning the photochemical operating efficiency of PSII. However, how this process adjusts throughout the warmest months in naturally heat-tolerant or sensitive species is unknown, and whether this influences the capacity to tolerate transient heat stress is untested. We therefore examined the PSII photophysiology of 10 coral species (with known thermal tolerances from shallow reef environments at Heron Island (Great Barrier Reef, Australia, in spring (October-November, 2015 vs. summer (February-March, 2016. Corals were maintained in flow-through aquaria and rapid light curve (RLC protocols using pulse amplitude modulated (PAM fluorometry captured changes in the PSII photoacclimation strategy, characterized as the minimum saturating irradiance (Ek, and the extent of photochemical ([1 – C], operating efficiency vs. non-photochemical ([1 – Q] energy dissipation. Values of Ek across species were >2-fold higher in all coral species in spring, consistent with a climate of higher overall light exposure (i.e., higher PAR from lower cloud cover, rainfall and wind speed compared with summer. Summer decreases in Ek were combined with a shift toward preferential photochemical quenching in all species. All coral species were subsequently subjected to thermal stress assays. An equivalent temperature-ramping profile of 1°C increase per day and then maintenance at 32°C was applied in each season. Despite the significant seasonal photoacclimation, the species hierarchy of thermal tolerance [maximum quantum yields of PSII (Fv/Fm, monitored at dawn and dusk] did not shift between seasons, except for Pocillopora

  5. Early-phase dynamics in coral recovery following cyclone disturbance on the inshore Great Barrier Reef, Australia

    Science.gov (United States)

    Sato, Yui; Bell, Sara C.; Nichols, Cassandra; Fry, Kent; Menéndez, Patricia; Bourne, David G.

    2018-06-01

    Coral recovery (the restoration of abundance and composition of coral communities) after disturbance is a key process that determines the resilience of reef ecosystems. To understand the mechanisms underlying the recovery process of coral communities, colony abundance and size distribution were followed on reefs around Pelorus Island, located in the inshore central region of the Great Barrier Reef, following a severe tropical cyclone in 2011 that caused dramatic loss of coral communities. Permanent quadrats (600 m2) were monitored biannually between 2012 and 2016, and individual coral colonies were counted, sized and categorized into morphological types. The abundance of coral recruits and coral cover were also examined using permanent quadrats and random line intercept transects, respectively. The number of colonies in the smallest size class (4-10 cm) increased substantially during the study period, driving the recovery of coral populations. The total number of coral colonies 5 yr post-cyclone reached between 73 and 122% of pre-cyclone levels though coral cover remained between 16 and 31% of pre-cyclone levels, due to the dominance of small coral colonies in the recovering communities. Temporal transitions of coral demography (i.e., colony-size distributions) illustrated that the number of recently established coral populations overtook communities of surviving colonies. Coral recruits (coral recovery. A shift in morphological composition of coral communities was also observed, with the relative abundance of encrusting corals reduced post-cyclone in contrast to their dominance prior to the disturbance. This study identifies the fine-scale processes involved in the initial recovery of coral reefs, providing insights into the dynamics of coral demography that are essential for determining coral reef resilience following major disturbance.

  6. Fecal bacterial communities of wild-captured and stranded green turtles (Chelonia mydas) on the Great Barrier Reef.

    Science.gov (United States)

    Ahasan, Md Shamim; Waltzek, Thomas B; Huerlimann, Roger; Ariel, Ellen

    2017-12-01

    Green turtles (Chelonia mydas) are endangered marine herbivores that break down food particles, primarily sea grasses, through microbial fermentation. However, the microbial community and its role in health and disease is still largely unexplored. In this study, we investigated and compared the fecal bacterial communities of eight wild-captured green turtles to four stranded turtles in the central Great Barrier Reef regions that include Bowen and Townsville. We used high-throughput sequencing analysis targeting the hypervariable V1-V3 regions of the bacterial 16S rRNA gene. At the phylum level, Firmicutes predominated among wild-captured green turtles, followed by Bacteroidetes and Proteobacteria. In contrast, Proteobacteria (Gammaproteobacteria) was the most significantly dominant phylum among all stranded turtles, followed by Bacteroidetes and Firmicutes. In addition, Fusobacteria was also significantly abundant in stranded turtles. No significant differences were found between the wild-captured turtles in Bowen and Townsville. At the family level, the core bacterial community consisted of 25 families that were identified in both the wild-captured and stranded green turtles, while two unique sets of 14 families each were only found in stranded or wild-captured turtles. The predominance of Bacteroides in all groups indicates the importance of these bacteria in turtle gut health. In terms of bacterial diversity and richness, wild-captured green turtles showed a higher bacterial diversity and richness compared with stranded turtles. The marked differences in the bacterial communities between wild-captured and stranded turtles suggest the possible dysbiosis in stranded turtles in addition to potential causal agents. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  7. Disease outbreaks, bleaching and a cyclone drive changes in coral assemblages on an inshore reef of the Great Barrier Reef

    Science.gov (United States)

    Haapkylä, J.; Melbourne-Thomas, J.; Flavell, M.; Willis, B. L.

    2013-09-01

    Coral disease is a major threat to the resilience of coral reefs; thus, understanding linkages between disease outbreaks and disturbances predicted to increase with climate change is becoming increasingly important. Coral disease surveys conducted twice yearly between 2008 and 2011 at a turbid inshore reef in the central Great Barrier Reef spanned two disturbance events, a coral bleaching event in 2009 and a severe cyclone (cyclone `Yasi') in 2011. Surveys of coral cover, community structure and disease prevalence throughout this 4-yr study provide a unique opportunity to explore cumulative impacts of disturbance events and disease for inshore coral assemblages. The principal coral disease at the study site was atramentous necrosis (AtN), and it primarily affected the key inshore, reef-building coral Montipora aequituberculata. Other diseases detected were growth anomalies, white syndrome and brown band syndrome. Diseases affected eight coral genera, although Montipora was, by far, the genus mostly affected. The prevalence of AtN followed a clear seasonal pattern, with disease outbreaks occurring only in wet seasons. Mean prevalence of AtN on Montipora spp. (63.8 % ± 3.03) was three- to tenfold greater in the wet season of 2009, which coincided with the 2009 bleaching event, than in other years. Persistent wet season outbreaks of AtN combined with the impacts of bleaching and cyclone events resulted in a 50-80 % proportional decline in total coral cover. The greatest losses of branching and tabular acroporids occurred following the low-salinity-induced bleaching event of 2009, and the greatest losses of laminar montiporids occurred following AtN outbreaks in 2009 and in 2011 following cyclone Yasi. The shift to a less diverse coral assemblage and the concomitant loss of structural complexity are likely to have long-term consequences for associated vertebrate and invertebrate communities on Magnetic Island reefs.

  8. Lower Mesophotic Coral Communities (60-125 m Depth of the Northern Great Barrier Reef and Coral Sea.

    Directory of Open Access Journals (Sweden)

    Norbert Englebert

    Full Text Available Mesophotic coral ecosystems in the Indo-Pacific remain relatively unexplored, particularly at lower mesophotic depths (≥60 m, despite their potentially large spatial extent. Here, we used a remotely operated vehicle to conduct a qualitative assessment of the zooxanthellate coral community at lower mesophotic depths (60-125 m at 10 different locations in the Great Barrier Reef Marine Park and the Coral Sea Commonwealth Marine Reserve. Lower mesophotic coral communities were present at all 10 locations, with zooxanthellate scleractinian corals extending down to ~100 metres on walls and ~125 m on steep slopes. Lower mesophotic coral communities were most diverse in the 60-80 m zone, while at depths of ≥100 m the coral community consisted almost exclusively of the genus Leptoseris. Collections of coral specimens (n = 213 between 60 and 125 m depth confirmed the presence of at least 29 different species belonging to 18 genera, including several potential new species and geographic/depth range extensions. Overall, this study highlights that lower mesophotic coral ecosystems are likely to be ubiquitous features on the outer reefs of the Great Barrier Reef and atolls of the Coral Sea, and harbour a generic and species richness of corals that is much higher than thus far reported. Further research efforts are urgently required to better understand and manage these ecosystems as part of the Great Barrier Reef Marine Park and Coral Sea Commonwealth Marine Reserve.

  9. Biodiversity of the Great Barrier Reef—how adequately is it protected?

    Directory of Open Access Journals (Sweden)

    Zoe T. Richards

    2018-05-01

    Full Text Available Background The Great Barrier Reef (GBR is the world’s most iconic coral reef ecosystem, recognised internationally as a World Heritage Area of outstanding significance. Safeguarding the biodiversity of this universally important reef is a core legislative objective; however, ongoing cumulative impacts including widespread coral bleaching and other detrimental impacts have heightened conservation concerns for the future of the GBR. Methods Here we review the literature to report on processes threatening species on the GBR, the status of marine biodiversity, and evaluate the extent of species-level monitoring and reporting. We assess how many species are listed as threatened at a global scale and explore whether these same species are protected under national threatened species legislation. We conclude this review by providing future directions for protecting potentially endangered elements of biodiversity within the GBR. Results Most of the threats identified to be harming the diversity of marine life on the GBR over the last two–three decades remain to be effectively addressed and many are worsening. The inherent resilience of this globally significant coral reef ecosystem has been seriously compromised and various elements of the biological diversity for which it is renowned may be at risk of silent extinction. We show at least 136 of the 12,000+ animal species known to occur on the GBR (approximately 20% of the 700 species assessed by the IUCN occur in elevated categories of threat (Critically Endangered, Endangered or Vulnerable at a global scale. Despite the wider background level of threat for these 136 species, only 23 of them are listed as threatened under regional or national legislation. Discussion To adequately protect the biodiversity values of the GBR, it may be necessary to conduct further targeted species-level monitoring and reporting to complement ecosystem management approaches. Conducting a vigorous value of information

  10. Pathways for Small Molecule Delivery to the Central Nervous System Across the Blood-Brain Barrier

    OpenAIRE

    Mikitsh, John L; Chacko, Ann-Marie

    2014-01-01

    The treatment of central nervous system (CNS) disease has long been difficult due to the ineffectiveness of drug delivery across the blood-brain barrier (BBB). This review summarizes important concepts of the BBB in normal versus pathophysiology and how this physical, enzymatic, and efflux barrier provides necessary protection to the CNS during drug delivery, and consequently treatment challenging. Small molecules account for the vast majority of available CNS drugs primarily due to their abi...

  11. Barriers to accessing abortion services and perspectives on using mifepristone and misoprostol at home in Great Britain.

    Science.gov (United States)

    Aiken, Abigail R A; Guthrie, Katherine A; Schellekens, Marlies; Trussell, James; Gomperts, Rebecca

    2018-02-01

    To examine reasons for seeking abortion services outside the formal healthcare system in Great Britain, where abortion is legally available. We conducted a mixed-methods study among women resident in England, Scotland, and Wales who requested at-home medication abortion through online telemedicine initiative Women on Web (WoW) between November 22, 2016, and March 22, 2017. We examined the demographics and circumstances of all women requesting early medication abortion and conducted a content analysis of a sample of their anonymized emails to the service to explore their reasons for seeking help. Over a 4-month period, 519 women contacted WoW seeking medication abortion. These women were diverse with respect to age, parity, and circumstance. One hundred eighty women reported 209 reasons for seeking abortion outside the formal healthcare setting. Among all reasons, 49% were access barriers, including long waiting times, distance to clinic, work or childcare commitments, lack of eligibility for free NHS services, and prior negative experiences of abortion care; 30% were privacy concerns, including lack of confidentiality of services, perceived or experienced stigma, and preferring the privacy and comfort of using pills at home; and 18% were controlling circumstances, including partner violence and partner/family control. Despite the presence of abortion services in Great Britain, a diverse group of women still experiences logistical and personal barriers to accessing care through the formal healthcare system, or prefer the privacy of conducting their abortions in their own homes. Health services commissioning bodies could address existing barriers if supported by policy frameworks. The presence of multiple barriers to accessing abortion care in Great Britain highlights the need for future guidelines to recommend a more woman-centered approach to service provision. Reducing the number of clinic visits and designing services to meet the needs of those living in

  12. Monitoring the environment and human sentiment on the Great Barrier Reef: Assessing the potential of collective sensing.

    Science.gov (United States)

    Becken, Susanne; Stantic, Bela; Chen, Jinyan; Alaei, Ali Reza; Connolly, Rod M

    2017-12-01

    With the growth of smartphone usage the number of social media posts has significantly increased and represents potentially valuable information for management, including of natural resources and the environment. Already, evidence of using 'human sensor' in crises management suggests that collective knowledge could be used to complement traditional monitoring. This research uses Twitter data posted from the Great Barrier Reef region, Australia, to assess whether the extent and type of data could be used to Great Barrier Reef organisations as part of their monitoring program. The analysis reveals that large amounts of tweets, covering the geographic area of interest, are available and that the pool of information providers is greatly enhanced by the large number of tourists to this region. A keyword and sentiment analysis demonstrates the usefulness of the Twitter data, but also highlights that the actual number of Reef-related tweets is comparatively small and lacks specificity. Suggestions for further steps towards the development of an integrative data platform that incorporates social media are provided. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Inferring coastal processes from regional-scale mapping of {sup 222}Radon and salinity: examples from the Great Barrier Reef, Australia

    Energy Technology Data Exchange (ETDEWEB)

    Stieglitz, Thomas C., E-mail: thomas.stieglitz@jcu.edu.a [AIMS-JCU, Townsville (Australia); Australian Institute of Marine Science, PMB NO 3, Townsville QLD 4810 (Australia); School of Engineering and Physical Sciences, James Cook University, Townsville QLD 4811 (Australia); Cook, Peter G., E-mail: peter.g.cook@csiro.a [CSIRO Land and Water, Private Bag 2, Glen Osmond SA 5064 (Australia); Burnett, William C., E-mail: wburnett@mailer.fsu.ed [Department of Oceanography, Florida State University, Tallahassee, FL 32306 (United States)

    2010-07-15

    The radon isotope {sup 222}Rn and salinity in coastal surface water were mapped on regional scales, to improve the understanding of coastal processes and their spatial variability. Radon was measured with a surface-towed, continuously recording multi-detector setup on a moving vessel. Numerous processes and locations of land-ocean interaction along the Central Great Barrier Reef coastline were identified and interpreted based on the data collected. These included riverine fluxes, terrestrially-derived fresh submarine groundwater discharge (SGD) and the tidal pumping of seawater through mangrove forests. Based on variations in the relationship of the tracers radon and salinity, some aspects of regional freshwater inputs to the coastal zone and to estuaries could be assessed. Concurrent mapping of radon and salinity allowed an efficient qualitative assessment of land-ocean interaction on various spatial and temporal scales, indicating that such surveys on coastal scales can be a useful tool to obtain an overview of SGD locations and processes.

  14. U-Th dating reveals regional-scale decline of branching Acropora corals on the Great Barrier Reef over the past century

    Science.gov (United States)

    Clark, Tara R.; Roff, George; Zhao, Jian-xin; Feng, Yue-xing; Done, Terence J.; McCook, Laurence J.; Pandolfi, John M.

    2017-09-01

    Hard coral cover on the Great Barrier Reef (GBR) is on a trajectory of decline. However, little is known about past coral mortality before the advent of long-term monitoring (circa 1980s). Using paleoecological analysis and high-precision uranium-thorium (U-Th) dating, we reveal an extensive loss of branching Acropora corals and changes in coral community structure in the Palm Islands region of the central GBR over the past century. In 2008, dead coral assemblages were dominated by large, branching Acropora and living coral assemblages by genera typically found in turbid inshore environments. The timing of Acropora mortality was found to be occasionally synchronous among reefs and frequently linked to discrete disturbance events, occurring in the 1920s to 1960s and again in the 1980s to 1990s. Surveys conducted in 2014 revealed low Acropora cover (shifted baseline.

  15. Wintering Sandhill Crane exposure to wind energy development in the central and southern Great Plains, USA

    Science.gov (United States)

    Pearse, Aaron T.; Brandt, David; Krapu, Gary

    2016-01-01

    Numerous wind energy projects have been constructed in the central and southern Great Plains, USA, the main wintering area for midcontinental Sandhill Cranes (Grus canadensis). In an initial assessment of the potential risks of wind towers to cranes, we estimated spatial overlap, investigated potential avoidance behavior, and determined the habitat associations of cranes. We used data from cranes marked with platform transmitting terminals (PTTs) with and without global positioning system (GPS) capabilities. We estimated the wintering distributions of PTT-marked cranes prior to the construction of wind towers, which we compared with current tower locations. Based on this analysis, we found 7% spatial overlap between the distributions of cranes and towers. When we looked at individually marked cranes, we found that 52% would have occurred within 10 km of a tower at some point during winter. Using data from cranes marked after tower construction, we found a potential indication of avoidance behavior, whereby GPS-marked cranes generally used areas slightly more distant from existing wind towers than would be expected by chance. Results from a habitat selection model suggested that distances between crane locations and towers may have been driven more by habitat selection than by avoidance, as most wind towers were constructed in locations not often selected by wintering cranes. Our findings of modest regional overlap and that few towers have been placed in preferred crane habitat suggest that the current distribution of wind towers may be of low risk to the continued persistence of wintering midcontinental Sandhill Cranes in the central and southern Great Plains.

  16. The importance of coastal altimetry retracking and detiding: A case study around the Great Barrier Reef, Australia

    DEFF Research Database (Denmark)

    Idris, Nurul H.; Deng, Xiaoli; Andersen, Ole Baltazar

    2014-01-01

    , fuzzy-retracked SLAs become available within 5 km of the coast; meanwhile it becomes more important to use pointwise tide modelling rather than state-of-the-art global tidal models, as the latter leave residual ocean tide signals in retracked SLAs. These improvements are demonstrated for Jason-2...... waveforms in the area of the Great Barrier Reef, Australia. Comparing the retrieved SLAs with in situ tide gauge data from Townsville and Bundaberg stations showed that the SLAs from this study generally outperform those from conventional methods, demonstrating that adequate waveform retracking and detiding...

  17. Electron thermal transport barrier and magnetohydrodynamic activity observed in Tokamak plasmas with negative central shear

    NARCIS (Netherlands)

    M.R. de Baar,; Hogeweij, G. M. D.; Cardozo, N. J. L.; Oomens, A. A. M.; Schüller, F. C.

    1997-01-01

    In the Rijnhuizen Tokamak Project, plasmas with steady-state negative central shear (NCS) are made with off-axis electron cyclotron heating. Shifting the power deposition by 2 mm results in a sharp transition of confinement. The good confinement branch features a transport barrier at the off-axis

  18. Building resilience into practical conservation: identifying local management responses to global climate change in the southern Great Barrier Reef

    Science.gov (United States)

    Maynard, J. A.; Marshall, P. A.; Johnson, J. E.; Harman, S.

    2010-06-01

    Climate change is now considered the greatest long-term threat to coral reefs, with some future change inevitable despite mitigation efforts. Managers must therefore focus on supporting the natural resilience of reefs, requiring that resilient reefs and reef regions be identified. We develop a framework for assessing resilience and trial it by applying the framework to target management responses to climate change on the southern Great Barrier Reef. The framework generates a resilience score for a site based on the evaluation of 19 differentially weighted indicators known or thought to confer resilience to coral reefs. Scores are summed, and sites within a region are ranked in terms of (1) their resilience relative to the other sites being assessed, and (2) the extent to which managers can influence their resilience. The framework was applied to 31 sites in Keppel Bay of the southern Great Barrier Reef, which has a long history of disturbance and recovery. Resilience and ‘management influence potential’ were both found to vary widely in Keppel Bay, informing site selection for the staged implementation of resilience-based management strategies. The assessment framework represents a step towards making the concept of resilience operational to reef managers and conservationists. Also, it is customisable, easy to teach and implement and effective in building support among local communities and stakeholders for management responses to climate change.

  19. The Gulf of Carpentaria heated Torres Strait and the Northern Great Barrier Reef during the 2016 mass coral bleaching event

    Science.gov (United States)

    Wolanski, E.; Andutta, F.; Deleersnijder, E.; Li, Y.; Thomas, C. J.

    2017-07-01

    The 2015/16 ENSO event increased the temperature of waters surrounding northeast Australia to above 30 °C, with large patches of water reaching 32 °C, for over two months, which led to severe bleaching of corals of the Northern Great Barrier Reef (NGBR). This study provides evidence gained from remote-sensing data, oceanographic data and oceanographic modeling, that three factors caused this excessive heating, namely: 1) the shutdown of the North Queensland Coastal Current, which would otherwise have flushed and cooled the Northern Coral Sea and the NGBR through tidal mixing 2) the advection of warm (>30 °C) water from the Gulf of Carpentaria eastward through Torres Strait and then southward over the NGBR continental shelf, and 3) presumably local solar heating. The eastward flux of this warm water through Torres Strait was driven by a mean sea level difference on either side of the strait that in turn was controlled by the wind, which also generated the southward advection of this warm water onto the NGBR shelf. On the NGBR shelf, the residence time of this warm water was longer inshore than offshore, and this may explain the observed cross-shelf gradient of coral bleaching intensity. The fate of the Great Barrier Reef is thus controlled by the oceanography of surrounding seas.

  20. Barriers and Facilitators to Central Venous Catheter Insertion: A Qualitative Study.

    Science.gov (United States)

    Cameron, Kenzie A; Cohen, Elaine R; Hertz, Joelle R; Wayne, Diane B; Mitra, Debi; Barsuk, Jeffrey H

    2018-03-14

    The aims of the study were to identify perceived barriers and facilitators to central venous catheter (CVC) insertion among healthcare providers and to understand the extent to which an existing Simulation-Based Mastery Learning (SBML) program may address barriers and leverage facilitators. Providers participating in a CVC insertion SBML train-the-trainer program, in addition to intensive care unit nurse managers, were purposively sampled from Veterans Administration Medical Centers located in geographically diverse areas. We conducted semistructured interviews to assess perceptions of barriers and facilitators to CVC insertion. Deidentified transcripts were analyzed using a grounded theory approach and the constant comparative method. We subsequently mapped identified barriers and facilitators to our SBML curriculum to determine whether or not the curriculum addresses these factors. We interviewed 28 providers at six Veterans Administration Medical Centers, identifying the following five overarching factors of perceived barriers to CVC insertion: (1) equipment, (2) personnel/staff, (3) setting or organizational context, (4) patient or provider, and (5) time-related barriers. Three overarching factors of facilitators emerged: (1) equipment, (2) personnel, and (3) setting or organizational context facilitators. The SBML curriculum seems to address most identified barriers, while leveraging many facilitators; building on the commonly identified facilitator of nursing staff contribution by expanding the curriculum to explicitly include nurse involvement could improve team efficiency and organizational culture of safety. Many identified facilitators (e.g., ability to use ultrasound, personnel confidence/competence) were also identified as barriers. Evidence-based SBML programs have the potential to amplify these facilitators while addressing the barriers by providing an opportunity to practice and master CVC insertion skills.

  1. Sheet-gravel evidence for a late Holocene tsunami run-up on beach dunes, Great Barrier Island, New Zealand

    Science.gov (United States)

    Nichol, Scott L.; Lian, Olav B.; Carter, Charles H.

    2003-01-01

    A semi-continuous sheet of granule to cobble-size clasts forms a distinctive deposit on sand dunes located on a coastal barrier in Whangapoua Bay, Great Barrier Island, New Zealand. The gravel sheet extends from the toe of the foredune to 14.3 m above mean sea level and 200 m landward from the beach. Clasts are rounded to sub-rounded and comprise lithologies consistent with local bedrock. Terrestrial sources for the gravel are considered highly unlikely due to the isolation of the dunes from hillslopes and streams. The only source for the clasts is the nearshore to inner shelf of Whangapoua Bay, where gravel sediments have been previously documented. The mechanism for transport of the gravel is unlikely to be storm surge due to the elevation of the deposit; maximum-recorded storm surge on this coast is 0.8 m above mean high water spring tide. Aeolian processes are also discounted due to the size of clasts and the elevation at which they occur. Tsunami is therefore considered the most probable mechanism for gravel transport. Minimum run-up height of the tsunami was 14.3 m, based on maximum elevation of gravel deposits. Optical ages on dune sands beneath and covering the gravel allow age bracketing to 0-4.7 ka. Within this time frame, numerous documented regional seismic and volcanic events could have generated the tsunami, notably submarine volcanism along the southern Kermadec arc to the east-southeast of Great Barrier Island where large magnitude events are documented for the late Holocene. Radiocarbon ages on shell from Maori middens that appear to have been reworked by tsunami run-up constrain the age of this event to post ca. 1400 AD. Regardless of the precise age of this event, the well-preserved nature of the Whangapoua gravel deposit provides for an improved understanding of the high degree of spatial variability in tsunami run-up.

  2. Great paleoearthquakes of the central Himalaya and their implications for seismotectonic models and seismic hazard assessment

    Science.gov (United States)

    Yule, D.; Lave, J.; Kumar, S.; Wesnousky, S.

    2007-12-01

    A growing body of paleoseismic data collected from more than ten sites in Nepal and India has documented large coseismic displacements at the thrust front (Main Frontal thrust (MFT)). Three great earthquakes have been identified: in ~A.D. 1410 centered north of Delhi, in A.D. 1505 centered in far-western Nepal, and in ~A.D. 1100 centered in eastern Nepal. It is noteworthy that wherever exposures of the MFT have been studied estimates of surface slip are consistently large; with a range of 9-26 m. Historic accounts of the 1505 earthquake describe strong shaking across a 600-km-long stretch of the central Himalaya. A magnitude for this event is estimated to be >Mw 8.5 based on the maximum extent of felt strong shaking, the 100 km width of the locked portion of the basal detachment, and an average slip of 10-15 m. Though no historic accounts exist for the ~1410 and ~1100 earthquakes, the similarity between their surface expression and the 1505 rupture suggests that these events may have been equally large. These surface-rupturing earthquakes are distinctly different from a host of blind thrust events (Mw 7.5-8.4) that dominate the historic record since A.D. 1505. Both blind and emergent earthquakes are presumed to rupture the basal detachment and release interseismic strain that accumulates near the base of the High Himalaya and carry it to the thrust front where Holocene shortening occurs at rates of 15-22 mm/yr. Whereas the surface-rupturing earthquakes clearly deform the thrust front, survey data from the region affected by the 1906 Dehra Dun earthquake suggest that blind events contribute negligible, if any, deformation to the frontal structures. The factors controlling whether or not surface rupture occurs on the MFT remain unconstrained, but the current data seem to suggest that >Mw 8.5 surface-rutpuring earthquakes are the primary contributors to the shortening observed at the thrust front. It is sobering to consider that the 'Big One' has not struck the

  3. Flood impacts in Keppel Bay, southern great barrier reef in the aftermath of cyclonic rainfall.

    Directory of Open Access Journals (Sweden)

    Alison M Jones

    Full Text Available In December 2010, the highest recorded Queensland rainfall associated with Tropical Cyclone 'Tasha' caused flooding of the Fitzroy River in Queensland, Australia. A massive flood plume inundated coral reefs lying 12 km offshore of the Central Queensland coast near Yeppoon and caused 40-100% mortality to coral fringing many of the islands of Keppel Bay down to a depth of ∼8 m. The severity of coral mortality was influenced by the level of exposure to low salinity seawater as a result of the reef's distance from the flood plume and to a lesser extent, water depth and whether or not the reef faced the plume source. There was no evidence in this study of mortality resulting from pollutants derived from the nearby Fitzroy Catchment, at least in the short term, suggesting that during a major flood, the impact of low salinity on corals outweighs that of pollutants. Recovery of the reefs in Keppel Bay from the 2010/2011 Fitzroy River flood is likely to take 10-15 years based on historical recovery periods from a similar event in 1991; potentially impacting visitor numbers for tourism and recreational usage. In the meantime, activities like snorkeling, diving and coral viewing will be focused on the few shallow reefs that survived the flood, placing even further pressure on their recovery. Reef regeneration, restoration and rehabilitation are measures that may be needed to support tourism in the short term. However, predictions of a warming climate, lower rainfall and higher intensity summer rain events in the Central and Coastal regions of Australia over the next decade, combined with the current anthropogenic influences on water quality, are likely to slow regeneration with consequent impact on long-term reef resilience.

  4. Bringing the "social" into sociohydrology: Conservation policy support in the Central Great Plains of Kansas, USA

    Science.gov (United States)

    Sanderson, Matthew R.; Bergtold, Jason S.; Heier Stamm, Jessica L.; Caldas, Marcellus M.; Ramsey, Steven M.

    2017-08-01

    Identifying means of empirically modeling the human component of a coupled, human-water system becomes critically important to further advances in sociohydrology. We develop a social-psychological model of environmental decision making that addresses four key challenges of incorporating social science into integrated models. We use the model to explain preferences for three conservation policies designed to conserve and protect water resources and aquatic ecosystems in the Smoky Hill River Basin, a semiarid agricultural region in the Central U.S. Great Plains. Further, we compare the model's capacity to explain policy preferences among members of two groups in the River Basin: agricultural producers and members of nonfarming communities. We find that financial obligation is the strongest and most consistent explanation of support for conservation policies among members of both groups. We also find that policy support is grounded in cultural values—deeply held ideas about right and wrong. Environmental values are particularly important explanations of policy support. The constellations of values invoked to make decisions about policies, and the social-psychological pathways linking values to policy support, can vary across policies and types of agents (farmers and nonfarmers). We discuss the implications of the results for future research in sociohydrology.

  5. Caspian Sea Oil – Still the Great Game for Central Eurasia

    Directory of Open Access Journals (Sweden)

    Andre Gunder Frank

    2015-08-01

    Full Text Available A book with a foreword by Pat Clawson of the National Defense University and editor of ORBIS, and dedicated to Ronald Reagan and Target Ozxal, announces its U.S. far-right wing political pedigree literally up front. However the book is chock full of information, alas most already well known to anyone even remotely familiar with the problematique under review; but it also offers some incisive analysis. The twelve contributed chapters by fourteen authors and coauthors are divided into three parts dedicated to examining and analyzing the general history and mutual background of the Caspian Sea region; to the ?ve littoral states of Azerbaijan, Russia, Iran, Kazakhstan, and Turkmenistan; and to three ‘external’ interested states, the United States, Turkey, and Georgia. Nonetheless, the review by each author goes well beyond the nominative boundaries assigned to him or her and trespasses over into the topics, territories and their relations assigned to other authors. Quite prop-erly so, in view of the mutually complex real-life interrelations in the Caspian Sea Basin, so that no topic or state could be adequately understood in itself other than in relation to the others. Indeed, we are witnessing the contemporary continuation of the nineteenth century “Great Game” for the control of Central Eurasia. However, the oil connection also reaches well beyond Caspian Sea and must make this book pertinent also to readers of this journal.

  6. Strontium isotope geochemistry of groundwater in the central part of the Dakota (Great Plains) aquifer, USA

    International Nuclear Information System (INIS)

    Gosselin, David C.; Edwin Harvey, F.; Frost, Carol; Stotler, Randy; Allen Macfarlane, P.

    2004-01-01

    The Dakota aquifer of the central and eastern Great Plains of the United States is an important source of water for municipal supplies, irrigation and industrial use. Although the regional flow system can be characterized generally as east to northeasterly from the Rocky Mountains towards the Missouri River, locally the flow systems are hydrologically complex. This study uses Sr isotopic data from groundwater and leached aquifer samples to document the complex subsystems within the Dakota aquifer in Nebraska and Kansas. The interaction of groundwater with the geologic material through which it flows has created spatial patterns in the isotopic measurements that are related to: long-term water-rock interaction, during which varying degrees of isotopic equilibrium between water and rock has been achieved; and the alteration of NaCl fluids by water-rock interaction. Specifically, Sr isotopic data distinguish brines from Kansas and western Nebraska from those in eastern Nebraska: the former are interpreted to reflect interaction with Permian rocks, whereas the latter record interaction with Pennsylvanian rocks. The Sr isotopic composition of groundwater from other parts of Nebraska and Kansas are a function of the dynamic interaction between groundwater and unlithified sediments (e.g., glacial till and loess), followed by interaction with oxidized and unoxidized sediments within the Dakota Formation. This study illustrates the power of combining Sr chemistry with more conventional geochemical data to obtain a more complete understanding of groundwater flow systems within regional aquifer systems where extensive monitoring networks do not exist

  7. Agrobiodiversity and genetic erosion of crop varieties and plant resources in the Central Great Caucasus

    Directory of Open Access Journals (Sweden)

    Maia Akhalkatsi

    2017-03-01

    Full Text Available Kazbegi Municipality is located in the Central Great Caucasus at an altitude between 1250 and 5047 m a.s.l. Agriculture of this area is extreme internal variability and complexity, with a multiplicity of highly localized providing the habitats and agricultural lands for much genetic erosion of crop varieties, animals, plants, fungi, and other life forms for wild plant resources. Historically, Kazbegi producers had begun cultivating the land to prepare for planting in of distribution local varieties of wheat, barley, rye, oats, etc. In the only cereals, legumes, herbs and some fruits are cultivated in alpine zone as the upper limit till the location of 2160 m a.s.l. Genetic erosion has been determined historically of aboriginal crops from sheep and cattle grazing problem and reached extreme levels from 1970s in Kazbegi Municipality and causes a problem to maintain agriculture. Plant resources remained in forests and subalpine grasslands and shrub lands. The problems of these materials are habitat degradation by disturbance in many forest types with destroyed and burned. Tree seedlings are grazing by animals and forest is not restoring naturally. Forest planting is good relation for restoration of plant wild species resources. Investigation on exchange on mountain agriculture and plant resources will now be rapidly accelerated in the vital interests of mountain communities.

  8. Kinds of damage that could result from a great earthquake in the central United States

    Science.gov (United States)

    Hooper, M.G.; Algermissen, S.T.

    1985-01-01

    In the winter of 1811-12 a series of three great earthquakes occurred in the New Madrid, Missouri seismic zone in the central United States. In addition to the three principal shocks, at least 15 other earthquakes of intensity VIII or more occurred within a year of the first large earthquake on December 16, 1811. The three main shocks were felt over the entire eastern United States. They were strong enough to cause minor damage cause minor damage as far away as Indiana and Ohio on the north, the Carolinas on the east, and southern Mississippi to the south. They were strong enough to cause severe or structural damage in parts of Missouri, Illinois, Indiana, Kentucky, Tennessee, Mississippi, and Arkansas. A later section in this article describes what happened in the epicentral region. Fortunately, few people lived in the severely shaken area in 1811; that is not the case today. What would happen if a series of earthquakes as large and numerous as the "New Madrid" earthquakes were to occur in the New Madrid seismic zone today?

  9. Spatial variability of initial 230Th/ 232Th in modern Porites from the inshore region of the Great Barrier Reef

    Science.gov (United States)

    Clark, Tara R.; Zhao, Jian-xin; Feng, Yue-xing; Done, Terry J.; Jupiter, Stacy; Lough, Janice; Pandolfi, John M.

    2012-02-01

    The main limiting factor in obtaining precise and accurate uranium-series (U-series) ages of corals that lived during the last few hundred years is the ability to constrain and correct for initial thorium-230 ( 230Th 0), which is proportionally much higher in younger samples. This is becoming particularly important in palaeoecological research where accurate chronologies, based on the 230Th chronometer, are required to pinpoint changes in coral community structure and the timing of mortality events in recent time (e.g. since European settlement of northern Australia in the 1850s). In this study, thermal ionisation mass spectrometry (TIMS) U-series dating of 43 samples of known ages collected from living Porites spp. from the far northern, central and southern inshore regions of the Great Barrier Reef (GBR) was performed to spatially constrain initial 230Th/ 232Th ( 230Th/ 232Th 0) variability. In these living Porites corals, the majority of 230Th/ 232Th 0 values fell within error of the conservative bulk Earth 230Th/ 232Th atomic value of 4.3 ± 4.3 × 10 -6 (2 σ) generally assumed for 230Th 0 corrections where the primary source is terrestrially derived. However, the results of this study demonstrate that the accuracy of 230Th ages can be further improved by using locally determined 230Th/ 232Th 0 values for correction, supporting the conclusion made by Shen et al. (2008) for the Western Pacific. Despite samples being taken from regions adjacent to contrasting levels of land modification, no significant differences were found in 230Th/ 232Th 0 between regions exposed to varying levels of sediment during river runoff events. Overall, 39 of the total 43 230Th/ 232Th 0 atomic values measured in samples from inshore reefs across the entire region show a normal distribution ranging from 3.5 ± 1.1 to 8.1 ± 1.1 × 10 -6, with a weighted mean of 5.76 ± 0.34 × 10 -6 (2 σ, MSWD = 8.1). Considering the scatter of the data, the weighted mean value with a more

  10. Role of Transporters in Central Nervous System Drug Delivery and Blood-Brain Barrier Protection: Relevance to Treatment of Stroke

    Directory of Open Access Journals (Sweden)

    Hrvoje Brzica

    2017-03-01

    Full Text Available Ischemic stroke is a leading cause of morbidity and mortality in the United States. The only approved pharmacologic treatment for ischemic stroke is thrombolysis via recombinant tissue plasminogen activator (r-tPA. A short therapeutic window and serious adverse events (ie, hemorrhage, excitotoxicity greatly limit r-tPA therapy, which indicates an essential need to develop novel stroke treatment paradigms. Transporters expressed at the blood-brain barrier (BBB provide a significant opportunity to advance stroke therapy via central nervous system delivery of drugs that have neuroprotective properties. Examples of such transporters include organic anion–transporting polypeptides (Oatps and organic cation transporters (Octs. In addition, multidrug resistance proteins (Mrps are transporter targets in brain microvascular endothelial cells that can be exploited to preserve BBB integrity in the setting of stroke. Here, we review current knowledge on stroke pharmacotherapy and demonstrate how endogenous BBB transporters can be targeted for improvement of ischemic stroke treatment.

  11. Excess seawater nutrients, enlarged algal symbiont densities and bleaching sensitive reef locations: 1. Identifying thresholds of concern for the Great Barrier Reef, Australia.

    Science.gov (United States)

    Wooldridge, Scott A

    2016-05-23

    Here, I contribute new insight into why excess seawater nutrients are an increasingly identified feature at reef locations that have low resistance to thermal stress. Specifically, I link this unfavourable synergism to the development of enlarged (suboptimal) zooxanthellae densities that paradoxically limit the capacity of the host coral to build tissue energy reserves needed to combat periods of stress. I explain how both theoretical predictions and field observations support the existence of species-specific 'optimal' zooxanthellae densities ~1.0-3.0×10 6 cellscm- 2 . For the central Great Barrier Reef (GBR), excess seawater nutrients that permit enlarged zooxanthellae densities beyond this optimum range are linked with seawater chlorophyll a>0.45μg·L -1 ; a eutrophication threshold previously shown to correlate with a significant loss in species for hard corals and phototrophic octocorals on the central GBR, and herein shown to correlate with enhanced bleaching sensitivity during the 1998 and 2002 mass bleaching events. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Future Scenarios as a Research Tool: Investigating Climate Change Impacts, Adaptation Options and Outcomes for the Great Barrier Reef, Australia.

    Science.gov (United States)

    Evans, Louisa S; Hicks, Christina C; Fidelman, Pedro; Tobin, Renae C; Perry, Allison L

    2013-01-01

    Climate change is a significant future driver of change in coastal social-ecological systems. Our knowledge of impacts, adaptation options, and possible outcomes for marine environments and coastal industries is expanding, but remains limited and uncertain. Alternative scenarios are a way to explore potential futures under a range of conditions. We developed four alternative future scenarios for the Great Barrier Reef and its fishing and tourism industries positing moderate and more extreme (2-3 °C above pre-industrial temperatures) warming for 2050 and contrasting 'limited' and 'ideal' ecological and social adaptation. We presented these scenarios to representatives of key stakeholder groups to assess the perceived viability of different social adaptation options to deliver desirable outcomes under varied contexts.

  13. The ugly face of tourism: Marine debris pollution linked to visitation in the southern Great Barrier Reef, Australia.

    Science.gov (United States)

    Wilson, Scott P; Verlis, Krista M

    2017-04-15

    Marine debris is one of the most significant issues facing oceans worldwide. The sources of this debris vary depending on proximity to urban centres and the nature of activities within an area. This paper examines the influence of tourism in the southern Great Barrier Reef (GBR), and its contribution to litter levels in the region. By conducting beach debris surveys on occupied and unoccupied islands, this study found that debris was prevalent throughout the region with significant differences in material types between locations. The greatest source of debris from publically accessible islands was tourist-related, with this source also influencing debris loads on nearby uninhabited islands. A focus on debris at Heron Island, showed that sites close to amenities had greater levels of tourist-sourced items like cigarette butts. These findings indicate the contribution of tourists to this problem and that working with operators and managers is needed to minimise visitor impacts. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Potential uranium host rocks and structures in the central Great Plains

    International Nuclear Information System (INIS)

    Zeller, E.J.; Dreschhoff, G.; Angino, E.; Holdoway, K.; Hakes, W.; Jayaprakash, G.; Crisler, K.; Saunders, D.F.

    1975-01-01

    A preliminary study was completed of the uranium potential of the Central Great Plains. The study area extends from longitude 99 to 104 0 W and is bounded by the North Platte River on the north and the Canadian River on the south. This region has no known commercial uranium accumulations, but is an area which contains formations with similar facies that are known to have deposits in other areas. A new method of utilizing petroleum exploration gamma-ray well log data was tested in the western Kansas portion of the survey area. Gamma activities in the Dakota and Morrison formations were computer-processed by trend surface analysis, statistically analyzed, and the anomalies were compared with regional geomorphic lineaments derived from satellite imagery as well as regional geology, to draw conclusions as to their origin and significance. Conclusions are: (1) possible uraniferous provinces have been outlined in the subsurface of western Kansas; (2) the new well log data approach can be used to define potential uraniferous provinces in any well-explored petroleum region; (3) the close spatial correlation between anomalies and regional geomorphic lineaments provides strong support for the concept that the lineaments represent vertical fracture zones which can act as preferred pathways for vertical fluid migration; and (4) the location of the strongest anomalies over impervious salt bodies indicates that any uranium bearing mineralizers must have moved down through the geologic section rather than upward. Recommendations are made to extend the application of the well-log approach, to do drilling and sampling to prove whether the anomalies are really due to uranium, and to add geobotanical and emanometric measurements during future studies

  15. Astrocytic TYMP and VEGFA drive blood-brain barrier opening in inflammatory central nervous system lesions.

    Science.gov (United States)

    Chapouly, Candice; Tadesse Argaw, Azeb; Horng, Sam; Castro, Kamilah; Zhang, Jingya; Asp, Linnea; Loo, Hannah; Laitman, Benjamin M; Mariani, John N; Straus Farber, Rebecca; Zaslavsky, Elena; Nudelman, German; Raine, Cedric S; John, Gareth R

    2015-06-01

    In inflammatory central nervous system conditions such as multiple sclerosis, breakdown of the blood-brain barrier is a key event in lesion pathogenesis, predisposing to oedema, excitotoxicity, and ingress of plasma proteins and inflammatory cells. Recently, we showed that reactive astrocytes drive blood-brain barrier opening, via production of vascular endothelial growth factor A (VEGFA). Here, we now identify thymidine phosphorylase (TYMP; previously known as endothelial cell growth factor 1, ECGF1) as a second key astrocyte-derived permeability factor, which interacts with VEGFA to induce blood-brain barrier disruption. The two are co-induced NFκB1-dependently in human astrocytes by the cytokine interleukin 1 beta (IL1B), and inactivation of Vegfa in vivo potentiates TYMP induction. In human central nervous system microvascular endothelial cells, VEGFA and the TYMP product 2-deoxy-d-ribose cooperatively repress tight junction proteins, driving permeability. Notably, this response represents part of a wider pattern of endothelial plasticity: 2-deoxy-d-ribose and VEGFA produce transcriptional programs encompassing angiogenic and permeability genes, and together regulate a third unique cohort. Functionally, each promotes proliferation and viability, and they cooperatively drive motility and angiogenesis. Importantly, introduction of either into mouse cortex promotes blood-brain barrier breakdown, and together they induce severe barrier disruption. In the multiple sclerosis model experimental autoimmune encephalitis, TYMP and VEGFA co-localize to reactive astrocytes, and correlate with blood-brain barrier permeability. Critically, blockade of either reduces neurologic deficit, blood-brain barrier disruption and pathology, and inhibiting both in combination enhances tissue preservation. Suggesting importance in human disease, TYMP and VEGFA both localize to reactive astrocytes in multiple sclerosis lesion samples. Collectively, these data identify TYMP as an

  16. Climate change in the Cairns and Great Barrier Reef region. Scope and Focus for an Integrated Assessment

    International Nuclear Information System (INIS)

    Crimp, S.; Balston, J.; Ash, A.; Anderson-Berry, L.; Done, T.; Greiner, R.; Hilbert, D.; Howden, M.; Jones, R.; Stokes, C.; Stoeckl, N.; Sutherst, B.; Whetton, P.

    2004-07-01

    This study was undertaken to determine the scope and focus for an integrated assessment of climate change impacts on, and adaptation options for, the Cairns Great Barrier Reef (CGBR) region. To achieve this, the authors employed both technical expertise and regional stakeholder input. This document describes the study objectives and the process used to meet these objectives, and provides an overview of the CGBR region, the views of technical experts on potential climate change impacts, stakeholder prioritisation of impacts and adaptation options, a list of perceived knowledge gaps, and a recommended structure for a future integrated assessment in the region. The aim of the study was to determine the scope and focus for an integrated regional assessment of climate change impacts on, and adaptation options for, the CGBR region. The key objectives of the study were: Define and describe the study region; Develop a process for the study, which includes key stakeholders in the region; Prepare a comprehensive list of the regional stakeholders; Brief regional stakeholders about potential climate changes in the region; Gain insight from stakeholders into the climatic dependencies of key sectors and issues in the region (agriculture, fishing, forestry, tourism, natural ecosystems, infrastructure, pests, diseases and human health); Identify possible adaptation and/or amelioration strategies for each sector; Identify synergies with other sectors, and possible barriers to undertaking climate change adaptation strategies; Identify knowledge gaps, research priorities and current activities that may need alteration or enhancement; Define the scope of a possible integrated assessment of climate change impacts on, and adaptation options for, the region

  17. Next generation of non-mammalian blood-brain barrier models to study parasitic infections of the central nervous system

    OpenAIRE

    Siddiqui, Ruqaiyyah; Edwards-Smallbone, James; Flynn, Robin; Khan, Naveed Ahmed

    2012-01-01

    Transmigration of neuropathogens across the blood-brain barrier is a key step in the development of central nervous system infections, making it a prime target for drug development. The ability of neuropathogens to traverse the blood-brain barrier continues to inspire researchers to understand the specific strategies and molecular mechanisms that allow them to enter the brain. The availability of models of the blood-brain barrier that closely mimic the situation in vivo offers unprecedented o...

  18. Water Quality and River Plume Monitoring in the Great Barrier Reef: An Overview of Methods Based on Ocean Colour Satellite Data

    Directory of Open Access Journals (Sweden)

    Michelle J. Devlin

    2015-09-01

    Full Text Available A strong driver of water quality change in the Great Barrier Reef (GBR is the pulsed or intermittent nature of terrestrial inputs into the GBR lagoon, including delivery of increased loads of sediments, nutrients, and toxicants via flood river plumes (hereafter river plumes during the wet season. Cumulative pressures from extreme weather with a high frequency of large scale flooding in recent years has been linked to the large scale reported decline in the health of inshore seagrass systems and coral reefs in the central areas of the GBR, with concerns for the recovery potential of these impacted ecosystems. Management authorities currently rely on remotely-sensed (RS and in situ data for water quality monitoring to guide their assessment of water quality conditions in the GBR. The use of remotely-sensed satellite products provides a quantitative and accessible tool for scientists and managers. These products, coupled with in situ data, and more recently modelled data, are valuable for quantifying the influence of river plumes on seagrass and coral reef habitat in the GBR. This article reviews recent remote sensing techniques developed to monitor river plumes and water quality in the GBR. We also discuss emerging research that integrates hydrodynamic models with remote sensing and in situ data, enabling us to explore impacts of different catchment management strategies on GBR water quality.

  19. Regional-scale variation in the distribution and abundance of farming damselfishes on Australia's Great Barrier Reef

    KAUST Repository

    Emslie, Michael J.

    2012-03-15

    Territorial damselfishes that manipulate ("farm") the algae in their territories can have a marked effect on benthic community structure and may influence coral recovery following disturbances. Despite the numerical dominance of farming species on many reefs, the importance of their grazing activities is often overlooked, with most studies only examining their roles over restricted spatial and temporal scales. We used the results of field surveys covering 9.5° of latitude of the Great Barrier Reef to describe the distribution, abundance and temporal dynamics of farmer communities. Redundancy analysis revealed unique subregional assemblages of farming species that were shaped by the combined effects of shelf position and, to a lesser extent, by latitude. These spatial patterns were largely stable through time, except when major disturbances altered the benthic community. Such disturbances affected the functional guilds of farmers in different ways. Since different guilds of farmers modify benthic community structure and affect survival of juvenile corals in different ways, these results have important implications for coral recovery following disturbances. © 2012 Springer-Verlag.

  20. A new gnathiid (Crustacea: Isopoda) parasitizing two species of requiem sharks from Lizard Island, Great Barrier Reef, Australia.

    Science.gov (United States)

    Coetzee, Maryke L; Smit, Nico J; Grutter, Alexandra S; Davies, Angela J

    2008-06-01

    Third-stage juveniles (praniza 3) of Gnathia grandilaris n. sp. were collected from the gill filaments and septa of 5 requiem sharks, including a white tip reef shark, Triaenodon obesus, and 4 grey reef sharks, Carcharhinus amblyrhynchos, at Lizard Island, Great Barrier Reef, Australia, in March 2002. Some juvenile gnathiids were then maintained in fresh sea water until they molted to adults. Adult males appeared 19 days following detachment of juveniles from host fishes, but no juveniles molted successfully into females. The current description is based, therefore, on bright field and scanning electron microscopy observations of adult males and third-stage juveniles. Unique features of the male include the triangular-shaped inferior medio-frontal process, 2 areolae on the dorsal surface of the pylopod, and a slender pleotelson (twice as long as wide) with lateral concavities. The third-stage juvenile has distinctive white pigmentation on the black pereon when alive, while the mandible has 9 triangular backwardly directed teeth. This species has the largest male and third-stage juvenile of any Gnathia spp. from Australia and of any gnathiid isopods associated with elasmobranchs.

  1. RESEARCH: Influence of Social, Biophysical, and Managerial Conditions on Tourism Experiences Within the Great Barrier Reef World Heritage Area.

    Science.gov (United States)

    Shafer; Inglis

    2000-07-01

    / Managing protected areas involves balancing the enjoyment of visitors with the protection of a variety of cultural and biophysical resources. Tourism pressures in the Great Barrier Reef World Heritage Area (GBRWHA) are creating concerns about how to strike this balance in a marine environment. Terrestrial-based research has led to conceptual planning and management frameworks that address issues of human use and resource protection. The limits of acceptable change (LAC) framework was used as a conceptual basis for a study of snorkeling at reef sites in the GBRWHA. The intent was to determine if different settings existed among tourism operators traveling to the reef and, if so, to identify specific conditions relating to those settings. Snorkelers (N = 1475) traveling with tourism operations of different sizes who traveled to different sites completed surveys. Results indicated that snorkelers who traveled with larger operations (more people and infrastructure) differed from those traveling with smaller operations (few people and little on-site infrastructure) on benefits received and in the way that specific conditions influenced their enjoyment. Benefits related to nature, escape, and family helped to define reef experiences. Conditions related to coral, fish, and operator staff had a positive influence on the enjoyment of most visitors but, number of people on the trip and site infrastructure may have the greatest potential as setting indicators. Data support the potential usefulness of visitor input in applying the LAC concept to a marine environment where tourism and recreational uses are rapidly changing.

  2. The relative abundance of dimethylsulfoniopropionate (DMSP) among other zwitterions in branching coral at Heron Island, southern Great Barrier Reef.

    Science.gov (United States)

    Swan, Hilton B; Deschaseaux, Elisabeth S M; Jones, Graham B; Eyre, Bradley D

    2017-07-01

    Dimethylsulfoniopropionate (DMSP) and eleven other target zwitterions were quantified in the branch tips of six Acropora species and Stylophora pistillata hard coral growing on the reef flat surrounding Heron Island in the southern Great Barrier Reef (GBR), Australia. Hydrophilic interaction liquid chromatography mass spectrometry (HILIC-MS) was used for sample analysis with isotope dilution MS applied to quantify DMSP. The concentration of DMSP was ten times greater in A. aspera than A. valida, with this difference being maintained throughout the spring, summer and winter seasons. In contrast, glycine betaine was present in significantly higher concentrations in these species during the summer than the winter. Exposure of branch tips of A. aspera to air and hypo-saline seawater for up to 1 h did not alter the concentrations of DMSP present in the coral when compared with control samples. DMSP was the most abundant target zwitterion in the six Acropora species examined, ranging from 44-78% of all target zwitterions in A. millepora and A. aspera, respectively. In contrast, DMSP only accounted for 7% in S. pistillata, with glycine betaine and stachydrine collectively accounting for 88% of all target zwitterions in this species. The abundance of DMSP in the six Acropora species examined points to Acropora coral being an important source for the biogeochemical cycling of sulfur throughout the GBR, since this reef-building branching coral dominates the coral cover of the GBR. Graphical Abstract HILIC-MS extracted ion chromatogram showing zwitterionic metabolites from the branching coral Acropora isopora.

  3. Regional-scale variation in the distribution and abundance of farming damselfishes on Australia's Great Barrier Reef

    KAUST Repository

    Emslie, Michael J.; Logan, Murray; Ceccarelli, Daniela M.; Cheal, Alistair J.; Hoey, Andrew; Miller, Ian R.; Sweatman, Hugh P A

    2012-01-01

    Territorial damselfishes that manipulate ("farm") the algae in their territories can have a marked effect on benthic community structure and may influence coral recovery following disturbances. Despite the numerical dominance of farming species on many reefs, the importance of their grazing activities is often overlooked, with most studies only examining their roles over restricted spatial and temporal scales. We used the results of field surveys covering 9.5° of latitude of the Great Barrier Reef to describe the distribution, abundance and temporal dynamics of farmer communities. Redundancy analysis revealed unique subregional assemblages of farming species that were shaped by the combined effects of shelf position and, to a lesser extent, by latitude. These spatial patterns were largely stable through time, except when major disturbances altered the benthic community. Such disturbances affected the functional guilds of farmers in different ways. Since different guilds of farmers modify benthic community structure and affect survival of juvenile corals in different ways, these results have important implications for coral recovery following disturbances. © 2012 Springer-Verlag.

  4. The Great Barrier Reef World Heritage Area seagrasses: Managing this iconic Australian ecosystem resource for the future

    Science.gov (United States)

    Coles, Robert G.; Rasheed, Michael A.; McKenzie, Len J.; Grech, Alana; York, Paul H.; Sheaves, Marcus; McKenna, Skye; Bryant, Catherine

    2015-02-01

    The Great Barrier Reef World Heritage Area (GBRWHA) includes one of the world's largest areas of seagrass (35,000 km2) encompassing approximately 20% of the world's species. Mapping and monitoring programs sponsored by the Australian and Queensland Governments and Queensland Port Authorities have tracked a worrying decrease in abundance and area since 2007. This decline has almost certainly been the result of a series of severe tropical storms and associated floods exacerbating existing human induced stressors. A complex variety of marine and terrestrial management actions and plans have been implemented to protect seagrass and other habitats in the GBRWHA. For seagrasses, these actions are inadequate. They provide an impression of effective protection of seagrasses; reduce the sense of urgency needed to trigger action; and waste the valuable and limited supply of "conservation capital". There is a management focus on ports, driven by public concerns about high profile development projects, which exaggerates the importance of these relatively concentrated impacts in comparison to the total range of threats and stressors. For effective management of seagrass at the scale of the GBRWHA, more emphasis needs to be placed on the connectivity between seagrass meadow health, watersheds, and all terrestrial urban and agricultural development associated with human populations. The cumulative impacts to seagrass from coastal and marine processes in the GBRWHA are not evenly distributed, with a mosaic of high and low vulnerability areas. This provides an opportunity to make choices for future coastal development plans that minimise stress on seagrass meadows.

  5. Prey Density Threshold and Tidal Influence on Reef Manta Ray Foraging at an Aggregation Site on the Great Barrier Reef.

    Directory of Open Access Journals (Sweden)

    Asia O Armstrong

    Full Text Available Large tropical and sub-tropical marine animals must meet their energetic requirements in a largely oligotrophic environment. Many planktivorous elasmobranchs, whose thermal ecologies prevent foraging in nutrient-rich polar waters, aggregate seasonally at predictable locations throughout tropical oceans where they are observed feeding. Here we investigate the foraging and oceanographic environment around Lady Elliot Island, a known aggregation site for reef manta rays Manta alfredi in the southern Great Barrier Reef. The foraging behaviour of reef manta rays was analysed in relation to zooplankton populations and local oceanography, and compared to long-term sighting records of reef manta rays from the dive operator on the island. Reef manta rays fed at Lady Elliot Island when zooplankton biomass and abundance were significantly higher than other times. The critical prey density threshold that triggered feeding was 11.2 mg m-3 while zooplankton size had no significant effect on feeding. The community composition and size structure of the zooplankton was similar when reef manta rays were feeding or not, with only the density of zooplankton changing. Higher zooplankton biomass was observed prior to low tide, and long-term (~5 years sighting data confirmed that more reef manta rays are also observed feeding during this tidal phase than other times. This is the first study to examine prey availability at an aggregation site for reef manta rays and it indicates that they feed in locations and at times of higher zooplankton biomass.

  6. Assessing community values for reducing agricultural emissions to improve water quality and protect coral health in the Great Barrier Reef

    Science.gov (United States)

    Rolfe, John; Windle, Jill

    2011-12-01

    Policymakers wanting to increase protection of the Great Barrier Reef from pollutants generated by agriculture need to identify when measures to improve water quality generate benefits to society that outweigh the costs involved. The research reported in this paper makes a contribution in several ways. First, it uses the improved science understanding about the links between management changes and reef health to bring together the analysis of costs and benefits of marginal changes, helping to demonstrate the appropriate way of addressing policy questions relating to reef protection. Second, it uses the scientific relationships to frame a choice experiment to value the benefits of improved reef health, with the results of mixed logit (random parameter) models linking improvements explicitly to changes in "water quality units." Third, the research demonstrates how protection values are consistent across a broader population, with some limited evidence of distance effects. Fourth, the information on marginal costs and benefits that are reported provide policymakers with information to help improve management decisions. The results indicate that while there is potential for water quality improvements to generate net benefits, high cost water quality improvements are generally uneconomic. A major policy implication is that cost thresholds for key pollutants should be set to avoid more expensive water quality proposals being selected.

  7. A multi-criteria approach to Great Barrier Reef catchment (Queensland, Australia) diffuse-source pollution problem.

    Science.gov (United States)

    Greiner, R; Herr, A; Brodie, J; Haynes, D

    2005-01-01

    This paper presents a multi-criteria based tool for assessing the relative impact of diffuse-source pollution to the Great Barrier Reef (GBR) from the river basins draining into the GBR lagoon. The assessment integrates biophysical and ecological data of water quality and pollutant concentrations with socio-economic information pertaining to non-point source pollution and (potential) pollutant impact. The tool generates scores for each river basin against four criteria, thus profiling the basins and enabling prioritization of management alternatives between and within basins. The results support policy development for pollution control through community participation, scientific data integration and expert knowledge contributed by people from across the catchment. The results specifically provided support for the Reef Water Quality Protection Plan, released in October 2003. The aim of the plan is to provide a framework for reducing discharge of sediment, nutrient and other diffuse-source loads and (potential) impact of that discharge and for prioritising management actions both between and within river basins.

  8. A Late Quaternary palynological and sedimentological record from two coastal swamps at southern Kaitoke, Great Barrier Island, New Zealand

    International Nuclear Information System (INIS)

    Horrocks, M.; Ogden, J.; Nichol, S.L.; Alloway, B.V.; Sutton, D.G.

    2000-01-01

    Pollen and sediment analyses of two cores from southern Kaitoke (Forsythes' Paddock and Blackwells' Bush), Great Barrier Island, show that at c. 7500 cal. yr BP, the area was an estuary with tidal flats and Avicennia. By c. 3000 cal. yr BP, a Restionaceae (Leptocarpus) salt marsh had developed in the estuary as marine influences lessened. By c. cal. 2550 yr BP, fresh water swamp (Cyperacceae-Gleichenia-Leptspermum) had replaced the salt marsh. Conifer-hardwood forest surrounding the southern Kaitoke sites from c. 7500-c. 2800 cal. yr BP was dominated by Daceydium, Metrosideros and Libocedrus. After c. 2800 cal. yr BP Metrosideros was replaced by Agathis, Phyllocladus and Prumnopitys taxifolia, suggesting climatic change to more variable conditions. The presence of the Kaharoa Tephra suggests that major Polynesian deforestation at southern Kaitoke began c. 600 cal. yr BP Minor pre-Kaharoa fire disturbance is evident c. 1750 cal. yr BP and c. 1290-970 cal. yr BP (author). 52 refs., 4 figs., 2 tabs

  9. Discursive barriers and cross-scale forest governance in Central Kalimantan, Indonesia

    Directory of Open Access Journals (Sweden)

    Caleb T. Gallemore

    2014-06-01

    Full Text Available Students of social-ecological systems have emphasized the need for effective cross-scale governance. We theorized that discursive barriers, particularly between technical and traditional practices, can act as a barrier to cross-scale collaboration. We analyzed the effects of discursive divides on collaboration on Reducing Emissions from Deforestation and Forest Degradation (REDD+ policy development in Central Kalimantan, an Indonesian province on the island of Borneo selected in 2010 to pilot subnational REDD+ policy. We argue that the complexities of bridging local land management practices and technical approaches to greenhouse gas emissions reduction and carbon offsetting create barriers to cross-scale collaboration. We tested these hypotheses using an exponential random graph model of collaboration among 36 organizations active in REDD+ policy in the province. We found that discursive divides were associated with a decreased probability of collaboration between organizations and that organizations headquartered outside the province were less likely to collaborate with organizations headquartered in the province. We conclude that bridging discursive communities presents a chicken-and-egg problem for cross-scale governance of social-ecological systems. In precisely the situations where it is most important, when bridging transnational standards with local knowledge and land management practices, it is the most difficult.

  10. Birds of a Great Basin Sagebrush Habitat in East-Central Nevada

    OpenAIRE

    United States Department of Agriculture, Forest Service

    1992-01-01

    Breeding bird populations ranged from 3.35 to 3.48 individuals/ha over a 3-year study conducted from 1981 to 1983. Brewer's sparrows, sage sparrows, sage thrashers, and black-throated sparrows were numerically dominant. Horned larks and western meadowlarks were less common. Results are compared with bird populations in Great Basin sagebrush habitats elsewhere in the United States.

  11. GEOMORPHIC AND HYDROGEOLOGICAL CONTROLS ON THE DISTRIBUTION OF WET MEADOWS IN THE CENTRAL GREAT BASIN

    Science.gov (United States)

    The Great Basin is an arid landscape dominated by dryland vegetation such as big sage and xeric grasses. Meadow complexes occur in mountain drainages and consist of discrete parcels of land up to several hectares in area that are characterized by high water tables and that primar...

  12. MANAGING AND RESTORING UPLAND RIPARIAN MEADOWS IN THE CENTRAL GREAT BASIN

    Science.gov (United States)

    Riparian meadow ecosystems in upland watersheds are of local and regional importance in the Great Basin. Covering only 1-3% of the total land area, these ecosystems contain a disproportionally large percentage of the region's biodiversity. Stream incision, due to natural and anth...

  13. Why the Central Dogma: on the nature of the great biological exclusion principle.

    Science.gov (United States)

    Koonin, Eugene V

    2015-09-16

    The Central Dogma of molecular biology posits that transfer of information from proteins back to nucleic acids does not occur in biological systems. I argue that the impossibility of reverse translation is indeed a major, physical exclusion principle that emerges due to the transition from the digital information carriers, nucleic acids, to analog information carriers, proteins, which involves irreversible suppression of the digital information.

  14. Humans and great apes cohabiting the forest ecosystem in central african republic harbour the same hookworms

    Czech Academy of Sciences Publication Activity Database

    Hasegawa, H.; Modrý, David; Kitagawa, M.; Shutt, K. A.; Todd, A.; Kalousová, B.; Profousová, I.; Petrželková, Klára Judita

    2014-01-01

    Roč. 8, č. 3 (2014), e2715 ISSN 1935-2735 Institutional support: RVO:60077344 Keywords : Necator spp. * mountain gorillas * infection * chimpanzees * Dzanga-Sangha Protected Areas * Central African Republic Subject RIV: EG - Zoology Impact factor: 4.446, year: 2014

  15. Humans and great apes cohabiting the forest ecosystem in Central African Republic harbour the same hookworms

    Czech Academy of Sciences Publication Activity Database

    Hasegawa, H.; Modrý, D.; Kitagawa, M.; Shutt, K. A.; Todd, A.; Kalousová, B.; Profousová, I.; Petrželková, Klára Judita

    2014-01-01

    Roč. 8, č. 3 (2014), e2715 ISSN 1935-2735 R&D Projects: GA ČR GA206/09/0927 Institutional support: RVO:68081766 Keywords : Necator spp. * mountain gorillas * infection * chimpanzees * Dzanga-Sangha Protected Areas, Central African Republic Subject RIV: EG - Zoology Impact factor: 4.446, year: 2014

  16. Digital Soil Mapping Using Landscape Stratification for Arid Rangelands in the Eastern Great Basin, Central Utah

    OpenAIRE

    Fonnesbeck, Brook B.

    2015-01-01

    Digital soil mapping typically involves inputs of digital elevation models, remotely sensed imagery, and other spatially explicit digital data as environmental covariates to predict soil classes and attributes over a landscape using statistical models. Digital imagery from Landsat 5, a digital elevation model, and a digital geology map were used as environmental covariates in a 67,000-ha study area of the Great Basin west of Fillmore, UT. A “pre-map” was created for selecting sampling locatio...

  17. Rapid survey protocol that provides dynamic information on reef condition to managers of the Great Barrier Reef.

    Science.gov (United States)

    Beeden, R J; Turner, M A; Dryden, J; Merida, F; Goudkamp, K; Malone, C; Marshall, P A; Birtles, A; Maynard, J A

    2014-12-01

    Managing to support coral reef resilience as the climate changes requires strategic and responsive actions that reduce anthropogenic stress. Managers can only target and tailor these actions if they regularly receive information on system condition and impact severity. In large coral reef areas like the Great Barrier Reef Marine Park (GBRMP), acquiring condition and impact data with good spatial and temporal coverage requires using a large network of observers. Here, we describe the result of ~10 years of evolving and refining participatory monitoring programs used in the GBR that have rangers, tourism operators and members of the public as observers. Participants complete Reef Health and Impact Surveys (RHIS) using a protocol that meets coral reef managers' needs for up-to-date information on the following: benthic community composition, reef condition and impacts including coral diseases, damage, predation and the presence of rubbish. Training programs ensure that the information gathered is sufficiently precise to inform management decisions. Participants regularly report because the demands of the survey methodology have been matched to their time availability. Undertaking the RHIS protocol we describe involves three ~20 min surveys at each site. Participants enter data into an online data management system that can create reports for managers and participants within minutes of data being submitted. Since 2009, 211 participants have completed a total of more than 10,415 surveys at more than 625 different reefs. The two-way exchange of information between managers and participants increases the capacity to manage reefs adaptively, meets education and outreach objectives and can increase stewardship. The general approach used and the survey methodology are both sufficiently adaptable to be used in all reef regions.

  18. Advances in monitoring the human dimension of natural resource systems: an example from the Great Barrier Reef

    Science.gov (United States)

    Marshall, N. A.; Bohensky, E.; Curnock, M.; Goldberg, J.; Gooch, M.; Nicotra, B.; Pert, P.; Scherl, L. M.; Stone-Jovicich, S.; Tobin, R. C.

    2016-11-01

    The aim of this paper is to demonstrate the feasibility and potential utility of decision-centric social-economic monitoring using data collected from Great Barrier Reef (Reef) region. The social and economic long term monitoring program (SELTMP) for the Reef is a novel attempt to monitor the social and economic dimensions of social-ecological change in a globally and nationally important region. It represents the current status and condition of the major user groups of the Reef with the potential to simultaneously consider trends, interconnections, conflicts, dependencies and vulnerabilities. Our approach was to combine a well-established conceptual framework with a strong governance structure and partnership arrangement that enabled the co-production of knowledge. The framework is a modification of the Millennium Ecosystem Assessment and it was used to guide indicator choice. Indicators were categorised as; (i) resource use and dependency, (ii) ecosystem benefits and well-being, and (iii) drivers of change. Data were collected through secondary datasets where existing and new datasets were created where not, using standard survey techniques. Here we present an overview of baseline results of new survey data from commercial-fishers (n = 210), marine-based tourism operators (n = 119), tourists (n = 2877), local residents (n = 3181), and other Australians (n = 2002). The indicators chosen describe both social and economic components of the Reef system and represent an unprecedented insight into the ways in which people currently use and depend on the Reef, the benefits that they derive, and how they perceive, value and relate to the Reef and each other. However, the success of a program such as the SELTMP can only occur with well-translated cutting-edge data and knowledge that are collaboratively produced, adaptive, and directly feeds into current management processes. We discuss how data from the SELTMP have already been incorporated into Reef management decision

  19. Prevalence of virus-like particles within a staghorn scleractinian coral ( Acropora muricata) from the Great Barrier Reef

    Science.gov (United States)

    Patten, N. L.; Harrison, P. L.; Mitchell, J. G.

    2008-09-01

    Transmission electron microscopy (TEM) was used to determine whether Acropora muricata coral colonies from the Great Barrier Reef (GBR), Australia, harboured virus-like particles (VLPs). VLPs were present in all coral colonies sampled at Heron Island (southern GBR) and in tagged coral colonies sampled in at least two of the three sampling periods at Lizard Island (northern GBR). VLPs were observed within gastrodermal and epidermal tissues, and on rarer occasions, within the mesoglea. These VLPs had similar morphologies to known prokaryotic and eukaryotic viruses in other systems. Icosahedral VLPs were observed most frequently, however, filamentous VLPs (FVLPs) and phage were also noted. There were no clear differences in VLP size, morphology or location within the tissues with respect to sample date, coral health status or site. The most common VLP morphotype exhibited icosahedral symmetry, 120-150 nm in diameter, with an electron-dense core and an electronlucent membrane. Larger VLPs of similar morphology were also common. VLPs occurred as single entities, in groups, or in dense clusters, either as free particles within coral tissues, or within membrane-bound vacuoles. VLPs were commonly observed within the perinuclear region, with mitochondria, golgi apparatus and crescent-shaped particles frequently observed within close proximity. The host(s) of these observed VLPs was not clear; however, the different sizes and morphologies of VLPs observed within A. muricata tissues suggest that viruses are infecting either the coral animal, zooxanthellae, intracellular bacteria and/or other coral-associated microbiota, or that the one host is susceptible to infection from more than one type of virus. These results add to the limited but emerging body of evidence that viruses represent another potentially important component of the coral holobiont.

  20. Effectiveness of benthic foraminiferal and coral assemblages as water quality indicators on inshore reefs of the Great Barrier Reef, Australia

    Science.gov (United States)

    Uthicke, S.; Thompson, A.; Schaffelke, B.

    2010-03-01

    Although the debate about coral reef decline focuses on global disturbances (e.g., increasing temperatures and acidification), local stressors (nutrient runoff and overfishing) continue to affect reef health and resilience. The effectiveness of foraminiferal and hard-coral assemblages as indicators of changes in water quality was assessed on 27 inshore reefs along the Great Barrier Reef. Environmental variables (i.e., several water quality and sediment parameters) and the composition of both benthic foraminiferal and hard-coral assemblages differed significantly between four regions (Whitsunday, Burdekin, Fitzroy, and the Wet Tropics). Grain size and organic carbon and nitrogen content of sediments, and a composite water column parameter (based on turbidity and concentrations of particulate matter) explained a significant amount of variation in the data (tested by redundancy analyses) in both assemblages. Heterotrophic species of foraminifera were dominant in sediments with high organic content and in localities with low light availability, whereas symbiont-bearing mixotrophic species were dominant elsewhere. A similar suite of parameters explained 89% of the variation in the FORAM index (a Caribbean coral reef health indicator) and 61% in foraminiferal species richness. Coral richness was not related to environmental setting. Coral assemblages varied in response to environmental variables, but were strongly shaped by acute disturbances (e.g., cyclones, Acanthaster planci outbreaks, and bleaching), thus different coral assemblages may be found at sites with the same environmental conditions. Disturbances also affect foraminiferal assemblages, but they appeared to recover more rapidly than corals. Foraminiferal assemblages are effective bioindicators of turbidity/light regimes and organic enrichment of sediments on coral reefs.

  1. Large-scale, multidirectional larval connectivity among coral reef fish populations in the Great Barrier Reef Marine Park

    KAUST Repository

    Williamson, David H.

    2016-11-15

    Larval dispersal is the key process by which populations of most marine fishes and invertebrates are connected and replenished. Advances in larval tagging and genetics have enhanced our capacity to track larval dispersal, assess scales of population connectivity, and quantify larval exchange among no-take marine reserves and fished areas. Recent studies have found that reserves can be a significant source of recruits for populations up to 40 km away, but the scale and direction of larval connectivity across larger seascapes remain unknown. Here, we apply genetic parentage analysis to investigate larval dispersal patterns for two exploited coral reef groupers (Plectropomus maculatus and Plectropomus leopardus) within and among three clusters of reefs separated by 60–220 km within the Great Barrier Reef Marine Park, Australia. A total of 69 juvenile P. maculatus and 17 juvenile P. leopardus (representing 6% and 9% of the total juveniles sampled, respectively) were genetically assigned to parent individuals on reefs within the study area. We identified both short-distance larval dispersal within regions (200 m to 50 km) and long-distance, multidirectional dispersal of up to ~250 km among regions. Dispersal strength declined significantly with distance, with best-fit dispersal kernels estimating median dispersal distances of ~110 km for P. maculatus and ~190 km for P. leopardus. Larval exchange among reefs demonstrates that established reserves form a highly connected network and contribute larvae for the replenishment of fished reefs at multiple spatial scales. Our findings highlight the potential for long-distance dispersal in an important group of reef fishes, and provide further evidence that effectively protected reserves can yield recruitment and sustainability benefits for exploited fish populations.

  2. Interactions between a Trawl fishery and spatial closures for biodiversity conservation in the Great Barrier Reef World Heritage Area, Australia.

    Directory of Open Access Journals (Sweden)

    Alana Grech

    Full Text Available BACKGROUND: The Queensland East Coast Otter Trawl Fishery (ECOTF for penaeid shrimp fishes within Australia's Great Barrier Reef World Heritage Area (GBRWHA. The past decade has seen the implementation of conservation and fisheries management strategies to reduce the impact of the ECOTF on the seabed and improve biodiversity conservation. New information from electronic vessel location monitoring systems (VMS provides an opportunity to review the interactions between the ECOTF and spatial closures for biodiversity conservation. METHODOLOGY AND RESULTS: We used fishing metrics and spatial information on the distribution of closures and modelled VMS data in a geographical information system (GIS to assess change in effort of the trawl fishery from 2001-2009 and to quantify the exposure of 70 reef, non-reef and deep water bioregions to trawl fishing. The number of trawlers and the number of days fished almost halved between 2001 and 2009 and new spatial closures introduced in 2004 reduced the area zoned available for trawl fishing by 33%. However, we found that there was only a relatively minor change in the spatial footprint of the fishery as a result of new spatial closures. Non-reef bioregions benefited the most from new spatial closures followed by deep and reef bioregions. CONCLUSIONS/SIGNIFICANCE: Although the catch of non target species remains an issue of concern for fisheries management, the small spatial footprint of the ECOTF relative to the size of the GBRWHA means that the impact on benthic habitats is likely to be negligible. The decline in effort as a result of fishing industry structural adjustment, increasing variable costs and business decisions of fishers is likely to continue a trend to fish only in the most productive areas. This will provide protection for most benthic habitats without any further legislative or management intervention.

  3. Epilithic Cyanobacterial Communities of a Marine Tropical Beach Rock (Heron Island, Great Barrier Reef): Diversity and Diazotrophy▿

    Science.gov (United States)

    Díez, Beatriz; Bauer, Karolina; Bergman, Birgitta

    2007-01-01

    The diversity and nitrogenase activity of epilithic marine microbes in a Holocene beach rock (Heron Island, Great Barrier Reef, Australia) with a proposed biological calcification “microbialite” origin were examined. Partial 16S rRNA gene sequences from the dominant mat (a coherent and layered pink-pigmented community spread over the beach rock) and biofilms (nonstratified, differently pigmented microbial communities of small shallow depressions) were retrieved using denaturing gradient gel electrophoresis (DGGE), and a clone library was retrieved from the dominant mat. The 16S rRNA gene sequences and morphological analyses revealed heterogeneity in the cyanobacterial distribution patterns. The nonheterocystous filamentous genus Blennothrix sp., phylogenetically related to Lyngbya, dominated the mat together with unidentified nonheterocystous filaments of members of the Pseudanabaenaceae and the unicellular genus Chroococcidiopsis. The dominance and three-dimensional intertwined distribution of these organisms were confirmed by nonintrusive scanning microscopy. In contrast, the less pronounced biofilms were dominated by the heterocystous cyanobacterial genus Calothrix, two unicellular Entophysalis morphotypes, Lyngbya spp., and members of the Pseudanabaenaceae family. Cytophaga-Flavobacterium-Bacteroides and Alphaproteobacteria phylotypes were also retrieved from the beach rock. The microbial diversity of the dominant mat was accompanied by high nocturnal nitrogenase activities (as determined by in situ acetylene reduction assays). A new DGGE nifH gene optimization approach for cyanobacterial nitrogen fixers showed that the sequences retrieved from the dominant mat were related to nonheterocystous uncultured cyanobacterial phylotypes, only distantly related to sequences of nitrogen-fixing cultured cyanobacteria. These data stress the occurrence and importance of nonheterocystous epilithic cyanobacteria, and it is hypothesized that such epilithic cyanobacteria

  4. Large-scale, multidirectional larval connectivity among coral reef fish populations in the Great Barrier Reef Marine Park

    KAUST Repository

    Williamson, David H.; Harrison, Hugo B.; Almany, Glenn R.; Berumen, Michael L.; Bode, Michael; Bonin, Mary C.; Choukroun, Severine; Doherty, Peter J.; Frisch, Ashley J.; Saenz-Agudelo, Pablo; Jones, Geoffrey P.

    2016-01-01

    Larval dispersal is the key process by which populations of most marine fishes and invertebrates are connected and replenished. Advances in larval tagging and genetics have enhanced our capacity to track larval dispersal, assess scales of population connectivity, and quantify larval exchange among no-take marine reserves and fished areas. Recent studies have found that reserves can be a significant source of recruits for populations up to 40 km away, but the scale and direction of larval connectivity across larger seascapes remain unknown. Here, we apply genetic parentage analysis to investigate larval dispersal patterns for two exploited coral reef groupers (Plectropomus maculatus and Plectropomus leopardus) within and among three clusters of reefs separated by 60–220 km within the Great Barrier Reef Marine Park, Australia. A total of 69 juvenile P. maculatus and 17 juvenile P. leopardus (representing 6% and 9% of the total juveniles sampled, respectively) were genetically assigned to parent individuals on reefs within the study area. We identified both short-distance larval dispersal within regions (200 m to 50 km) and long-distance, multidirectional dispersal of up to ~250 km among regions. Dispersal strength declined significantly with distance, with best-fit dispersal kernels estimating median dispersal distances of ~110 km for P. maculatus and ~190 km for P. leopardus. Larval exchange among reefs demonstrates that established reserves form a highly connected network and contribute larvae for the replenishment of fished reefs at multiple spatial scales. Our findings highlight the potential for long-distance dispersal in an important group of reef fishes, and provide further evidence that effectively protected reserves can yield recruitment and sustainability benefits for exploited fish populations.

  5. Host-specific interactions with environmental factors shape the distribution of symbiodinium across the Great Barrier Reef.

    Directory of Open Access Journals (Sweden)

    Linda Tonk

    Full Text Available The endosymbiotic dinoflagellates (genus Symbiodinium within coral reef invertebrates are critical to the survival of the holobiont. The genetic variability of Symbiodinium may contribute to the tolerance of the symbiotic association to elevated sea surface temperatures (SST. To assess the importance of factors such as the local environment, host identity and biogeography in driving Symbiodinium distributions on reef-wide scales, data from studies on reef invertebrate-Symbiodinium associations from the Great Barrier Reef (GBR were compiled.The resulting database consisted of 3717 entries from 26 studies. It was used to explore ecological patterns such as host-specificity and environmental drivers structuring community complexity using a multi-scalar approach. The data was analyzed in several ways: (i frequently sampled host species were analyzed independently to investigate the influence of the environment on symbiont distributions, thereby excluding the influence of host specificity, (ii host species distributions across sites were added as an environmental variable to determine the contribution of host identity on symbiont distribution, and (iii data were pooled based on clade (broad genetic groups dividing the genus Symbiodinium to investigate factors driving Symbiodinium distributions using lower taxonomic resolution. The results indicated that host species identity plays a dominant role in determining the distribution of Symbiodinium and environmental variables shape distributions on a host species-specific level. SST derived variables (especially SSTstdev most often contributed to the selection of the best model. Clade level comparisons decreased the power of the predictive model indicating that it fails to incorporate the main drivers behind Symbiodinium distributions.Including the influence of different host species on Symbiodinium distributional patterns improves our understanding of the drivers behind the complexity of Symbiodinium

  6. Chimerism in wild adult populations of the broadcast spawning coral Acropora millepora on the Great Barrier Reef.

    Directory of Open Access Journals (Sweden)

    Eneour Puill-Stephan

    2009-11-01

    Full Text Available Chimeras are organisms containing tissues or cells of two or more genetically distinct individuals, and are known to exist in at least nine phyla of protists, plants, and animals. Although widespread and common in marine invertebrates, the extent of chimerism in wild populations of reef corals is unknown.The extent of chimerism was explored within two populations of a common coral, Acropora millepora, on the Great Barrier Reef, Australia, by using up to 12 polymorphic DNA microsatellite loci. At least 2% and 5% of Magnetic Island and Pelorus Island populations of A. millepora, respectively, were found to be chimeras (3% overall, based on conservative estimates. A slightly less conservative estimate indicated that 5% of colonies in each population were chimeras. These values are likely to be vast underestimates of the true extent of chimerism, as our sampling protocol was restricted to a maximum of eight branches per colony, while most colonies consist of hundreds of branches. Genotypes within chimeric corals showed high relatedness, indicating that genetic similarity is a prerequisite for long-term acceptance of non-self genotypes within coral colonies.While some brooding corals have been shown to form genetic chimeras in their early life history stages under experimental conditions, this study provides the first genetic evidence of the occurrence of coral chimeras in the wild and of chimerism in a broadcast spawning species. We hypothesize that chimerism is more widespread in corals than previously thought, and suggest that this has important implications for their resilience, potentially enhancing their capacity to compete for space and respond to stressors such as pathogen infection.

  7. Why the Central Dogma: on the nature of the great biological exclusion principle

    OpenAIRE

    Koonin, Eugene V.

    2015-01-01

    Abstract The Central Dogma of molecular biology posits that transfer of information from proteins back to nucleic acids does not occur in biological systems. I argue that the impossibility of reverse translation is indeed a major, physical exclusion principle that emerges due to the transition from the digital information carriers, nucleic acids, to analog information carriers, proteins, which involves irreversible suppression of the digital information. Reviewers This article was reviewed by...

  8. Stratigraphic evidence of desertification in the west-central Great Plains within the past 1000 yr

    Science.gov (United States)

    Madole, R.F.

    1994-01-01

    Stratigraphic and geomorphic relations, archaeological data, and eight radiocarbon ages at five widely scattered localities in northeastern Colorado indicate that eolian sand was mobilized over broad areas within the past 1000 yr. The mobilization began after 1 ka, was episodic, and ended at some as yet undetermined time prior to the latter part of the 19th century. Given that climate-model simulations suggest only slight variation in average surface temperature and annual precipitation in this region during the past 1000 yr, this part of the Great Plains evidently is near the threshold of widespread eolian sand transport under the present climate. -Author

  9. OMI NO2 in the Central US Great Plains: How Well Do We Interpret NO2 Trends?

    Science.gov (United States)

    Kollonige, D. E.; Duncan, B. N.; Thompson, A. M.; Lamsal, L. N.

    2017-12-01

    Several areas over the Central US show statistically significant increases in OMI NO2 levels of 10-30% in the last 10 years versus the generally decreasing trends over most of CONUS. Are these changes in OMI NO2 a result of human activity, meteorology, or a combination of both? To answer this, we examine regions in the Central US Great Plains that have multiple plausible sources for the observed trends, considering impacts of land surface changes, agriculture growth, oil and gas operations, and drought conditions. We find that changes to the land surface appear to contribute to some of the observed anomalies due to tree removal in the Black Hills National Forest, South Dakota, and additional livestock farming in the Sandhills of Nebraska. However, increasing OMI NO2 also corresponds to several areas with growing agriculture business (ex. South Dakota and Nebraska) and oil and gas activity (ex. Williston Basin in North Dakota and Permian Basin in TX). To understand the relationship between the observed NO2 variability and the regional meteorological conditions over the last decade, we analyze the time series and correlations between OMI NO2, NH3 (an agriculture tracer), surface temperature, normalized difference vegetation index (NDVI) from Landsat, and the Palmer Drought Severity Index (PDSI). In 2012, drought conditions affect NO2, NH3 and NDVI observations across the Central US. Areas where dryland farming and livestock grazing are predominant (Central SD, ND, KS, and NE) are less sensitive to drought and changes in temperature. This suggests positive OMI NO2 trends are caused by increased production in wheats and livestock in the Northern Great Plains. These study regions in the Central US, impacted by local emissions and meteorology, are valuable for evaluating future trend analyses including the continuation of OMI-type NO2 retrievals from the TROPOMI and TEMPO satellite instruments.

  10. Central Pontine and Extrapontine Myelinolysis: The Great Masquerader—An Autopsy Case Report

    Directory of Open Access Journals (Sweden)

    Sajish Jacob

    2014-01-01

    Full Text Available Central pontine myelinolysis is a demyelinating disorder characterized by the loss of myelin in the center of the basis pontis usually caused by rapid correction of chronic hyponatremia. The clinical features vary depending on the extent of involvement. Demyelination can occur outside the pons as well and diagnosis can be challenging if both pontine and extrapontine areas are involved. We herein report a case of myelinolysis involving pons, lateral geniculate bodies, subependymal region, and spinal cord. To the best of our knowledge, this case represents the second case of spinal cord involvement in osmotic demyelination syndrome and the first case of involvement of thoracic region of spinal cord.

  11. Central Pontine and Extrapontine Myelinolysis: The Great Masquerader—An Autopsy Case Report

    Science.gov (United States)

    Jacob, Sajish; Nikolic, Dejan; Gundogdu, Betul; Ong, Shirley

    2014-01-01

    Central pontine myelinolysis is a demyelinating disorder characterized by the loss of myelin in the center of the basis pontis usually caused by rapid correction of chronic hyponatremia. The clinical features vary depending on the extent of involvement. Demyelination can occur outside the pons as well and diagnosis can be challenging if both pontine and extrapontine areas are involved. We herein report a case of myelinolysis involving pons, lateral geniculate bodies, subependymal region, and spinal cord. To the best of our knowledge, this case represents the second case of spinal cord involvement in osmotic demyelination syndrome and the first case of involvement of thoracic region of spinal cord. PMID:24716023

  12. Solving the Blood-Brain Barrier Challenge for the Effective Treatment of HIV Replication in the Central Nervous System.

    Science.gov (United States)

    Bertrand, Luc; Nair, Madhavan; Toborek, Michal

    2016-01-01

    Recent decades mark a great progress in the treatment of HIV infection. What was once a deadly disease is now a chronic infection. However, HIV-infected patients are prone to develop comorbidities, which severely affect their daily functions. For example, a large population of patients develop a variety of neurological and cognitive complications, called HIV associated neurological disorders (HAND). Despite efficient repression of viral replication in the periphery, evidence shows that the virus can remain active in the central nervous system (CNS). This low level of replication is believed to result in a progression of neurocognitive dysfunction in infected individuals. Insufficient viral inhibition in the brain results from the inability of several treatment drugs in crossing the blood-brain barrier (BBB) and reaching therapeutic concentrations in the CNS. The current manuscript discusses several strategies that are being developed to enable therapeutics to cross the BBB, including bypassing BBB, inhibition of efflux transporters, the use of active transporters present at the BBB, and nanotechnology. The increased concentration of therapeutics in the CNS is desirable to prevent viral replication; however, potential side effects of anti-retroviral drugs need also to be taken into consideration.

  13. Prediction of Central Nervous System Side Effects Through Drug Permeability to Blood-Brain Barrier and Recommendation Algorithm.

    Science.gov (United States)

    Fan, Jun; Yang, Jing; Jiang, Zhenran

    2018-04-01

    Drug side effects are one of the public health concerns. Using powerful machine-learning methods to predict potential side effects before the drugs reach the clinical stages is of great importance to reduce time consumption and protect the security of patients. Recently, researchers have proved that the central nervous system (CNS) side effects of a drug are closely related to its permeability to the blood-brain barrier (BBB). Inspired by this, we proposed an extended neighborhood-based recommendation method to predict CNS side effects using drug permeability to the BBB and other known features of drug. To the best of our knowledge, this is the first attempt to predict CNS side effects considering drug permeability to the BBB. Computational experiments demonstrated that drug permeability to the BBB is an important factor in CNS side effects prediction. Moreover, we built an ensemble recommendation model and obtained higher AUC score (area under the receiver operating characteristic curve) and AUPR score (area under the precision-recall curve) on the data set of CNS side effects by integrating various features of drug.

  14. Satellite-Derived Photic Depth on the Great Barrier Reef: Spatio-Temporal Patterns of Water Clarity

    Directory of Open Access Journals (Sweden)

    Scarla Weeks

    2012-11-01

    Full Text Available Detecting changes to the transparency of the water column is critical for understanding the responses of marine organisms, such as corals, to light availability. Long-term patterns in water transparency determine geographical and depth distributions, while acute reductions cause short-term stress, potentially mortality and may increase the organisms’ vulnerability to other environmental stressors. Here, we investigated the optimal, operational algorithm for light attenuation through the water column across the scale of the Great Barrier Reef (GBR, Australia. We implemented and tested a quasi-analytical algorithm to determine the photic depth in GBR waters and matched regional Secchi depth (ZSD data to MODIS-Aqua (2002–2010 and SeaWiFS (1997–2010 satellite data. The results of the in situ ZSD/satellite data matchup showed a simple bias offset between the in situ and satellite retrievals. Using a Type II linear regression of log-transformed satellite and in situ data, we estimated ZSD and implemented the validated ZSD algorithm to generate a decadal satellite time series (2002–2012 for the GBR. Water clarity varied significantly in space and time. Seasonal effects were distinct, with lower values during the austral summer, most likely due to river runoff and increased vertical mixing, and a decline in water clarity between 2008–2012, reflecting a prevailing La Niña weather pattern. The decline in water clarity was most pronounced in the inshore area, where a significant decrease in mean inner shelf ZSD of 2.1 m (from 8.3 m to 6.2 m occurred over the decade. Empirical Orthogonal Function Analysis determined the dominance of Mode 1 (51.3%, with the greatest variation in water clarity along the mid-shelf, reflecting the strong influence of oceanic intrusions on the spatio-temporal patterns of water clarity. The newly developed photic depth product has many potential applications for the GBR from water quality monitoring to analyses of

  15. Using MODIS data for understanding changes in seagrass meadow health: a case study in the Great Barrier Reef (Australia).

    Science.gov (United States)

    Petus, Caroline; Collier, Catherine; Devlin, Michelle; Rasheed, Michael; McKenna, Skye

    2014-07-01

    Stretching more than 2000 km along the Queensland coast, the Great Barrier Reef Marine Park (GBR) shelters over 43,000 square km of seagrass meadows. Despite the status of marine protected area and World Heritage listing of the GBR, local seagrass meadows are under stress from reduced water quality levels; with reduction in the amount of light available for seagrass photosynthesis defined as the primary cause of seagrass loss throughout the GBR. Methods have been developed to map GBR plume water types by using MODIS quasi-true colour (hereafter true colour) images reclassified in function of their dominant colour. These data can be used as an interpretative tool for understanding changes in seagrass meadow health (as defined in this study by the seagrass area and abundance) at different spatial and temporal scales. We tested this method in Cleveland Bay, in the northern GBR, where substantial loss in seagrass area and biomass was detected by annual monitoring from 2007 to 2011. A strong correlation was found between bay-wide seagrass meadow area and biomass and exposure to turbid Primary (sediment-dominated) water type. There was also a strong correlation between the changes of biomass and area of individual meadows and exposure of seagrass ecosystems to Primary water type over the 5-year period. Seagrass meadows were also grouped according to the dominant species within each meadow, irrespective of location within Cleveland Bay. These consolidated community types did not correlate well with the exposure to Primary water type, and this is likely to be due to local environmental conditions with the individual meadows that comprise these groupings. This study proved that remote sensing data provide the synoptic window and repetitivity required to investigate changes in water quality conditions over time. Remote sensing data provide an opportunity to investigate the risk of marine-coastal ecosystems to light limitation due to increased water turbidity when in situ

  16. Next generation of non-mammalian blood-brain barrier models to study parasitic infections of the central nervous system

    Science.gov (United States)

    Siddiqui, Ruqaiyyah; Edwards-Smallbone, James; Flynn, Robin; Khan, Naveed Ahmed

    2012-01-01

    Transmigration of neuropathogens across the blood-brain barrier is a key step in the development of central nervous system infections, making it a prime target for drug development. The ability of neuropathogens to traverse the blood-brain barrier continues to inspire researchers to understand the specific strategies and molecular mechanisms that allow them to enter the brain. The availability of models of the blood-brain barrier that closely mimic the situation in vivo offers unprecedented opportunities for the development of novel therapeutics. PMID:21921682

  17. Barriers to utilization of postnatal care at village level in Klaten district, central Java Province, Indonesia.

    Science.gov (United States)

    Probandari, Ari; Arcita, Akhda; Kothijah, Kothijah; Pamungkasari, Eti Poncorini

    2017-08-07

    Maternal health remains a persisting public health challenge in Indonesia. Postnatal complications, in particular, are considered as maternal health problems priority that should be addressed. Conducting adequate care for postnatal complications will improve the quality of life of mothers and babies. With the universal health coverage implementation, the Indonesian government provides free maternal and child health services close to clients at the village level, which include postnatal care. Our study aimed to explore barriers to utilization of postnatal care at the village level in Klaten district, Central Java Province, Indonesia. A qualitative study was conducted in March 2015 - June 2016 in Klaten district, Central Java, Indonesia. We selected a total of 19 study participants, including eight mothers with postnatal complications, six family members, and five village midwives for in-depth interviews. We conducted a content analysis technique on verbatim transcripts of the interviews using open code software. This study found three categories of barriers to postnatal care utilization in villages: mother and family members' health literacy on postnatal care, sociocultural beliefs and practices, and health service responses. Most mothers did not have adequate knowledge and skills regarding postnatal care that reflected how they lacked awareness and practice of postnatal care. Inter-generational norms and myths hindered mothers from utilizing postnatal care and from having adequate nutritional intake during the postnatal period. Mothers and family members conducted unsafe self-treatment to address perceived minor postnatal complication. Furthermore, social power from extended family influenced the postnatal care health literacy for mother and family members. Postnatal care in the village lacked patient-centered care practices. Additionally, midwives' workloads and capacities to conduct postnatal information, education and counseling were also issues. Despite the

  18. Gpr124 is essential for blood-brain barrier integrity in central nervous system disease.

    Science.gov (United States)

    Chang, Junlei; Mancuso, Michael R; Maier, Carolina; Liang, Xibin; Yuki, Kanako; Yang, Lu; Kwong, Jeffrey W; Wang, Jing; Rao, Varsha; Vallon, Mario; Kosinski, Cynthia; Zhang, J J Haijing; Mah, Amanda T; Xu, Lijun; Li, Le; Gholamin, Sharareh; Reyes, Teresa F; Li, Rui; Kuhnert, Frank; Han, Xiaoyuan; Yuan, Jenny; Chiou, Shin-Heng; Brettman, Ari D; Daly, Lauren; Corney, David C; Cheshier, Samuel H; Shortliffe, Linda D; Wu, Xiwei; Snyder, Michael; Chan, Pak; Giffard, Rona G; Chang, Howard Y; Andreasson, Katrin; Kuo, Calvin J

    2017-04-01

    Although blood-brain barrier (BBB) compromise is central to the etiology of diverse central nervous system (CNS) disorders, endothelial receptor proteins that control BBB function are poorly defined. The endothelial G-protein-coupled receptor (GPCR) Gpr124 has been reported to be required for normal forebrain angiogenesis and BBB function in mouse embryos, but the role of this receptor in adult animals is unknown. Here Gpr124 conditional knockout (CKO) in the endothelia of adult mice did not affect homeostatic BBB integrity, but resulted in BBB disruption and microvascular hemorrhage in mouse models of both ischemic stroke and glioblastoma, accompanied by reduced cerebrovascular canonical Wnt-β-catenin signaling. Constitutive activation of Wnt-β-catenin signaling fully corrected the BBB disruption and hemorrhage defects of Gpr124-CKO mice, with rescue of the endothelial gene tight junction, pericyte coverage and extracellular-matrix deficits. We thus identify Gpr124 as an endothelial GPCR specifically required for endothelial Wnt signaling and BBB integrity under pathological conditions in adult mice. This finding implicates Gpr124 as a potential therapeutic target for human CNS disorders characterized by BBB disruption.

  19. Opening of brain blood barrier induced by red light and central analgesic improvement of cobra neurotoxin.

    Science.gov (United States)

    Ye, Yong; Li, Yue; Fang, Fei

    2014-05-05

    Cobra neurotoxin (NT) has central analgesic effects, but it is difficult to pass through brain blood barrier (BBB). A novel method of red light induction is designed to help NT across BBB, which is based on photosensitizer activation by red light to generate reactive oxygen species (ROS) to open BBB. The effects were evaluated on cell models and animals in vivo with illumination by semiconductor laser at 670nm on photosensitizer pheophorbide isolated from silkworm excrement. Brain microvascular endothelial cells and astrocytes were co-cultured to build up BBB cell model. The radioactivity of (125)I-NT was measured in cells and tissues for NT permeation. Three ways of cranial irradiation, nasal cavity and intravascular irradiation were tested with combined injection of (125)I-NT 20μg/kg and pheophorbide 100μg/kg to rats, and organs of rats were separated and determined the radioactivity. Paw pressure test in rats, hot plate and writhing test in mice were applied to appraise the analgesic effects. NT across BBB cell model increased with time of illumination, and reached stable level after 60min. So did ROS in cells. NT mainly distributed in liver and kidney of rats, significantly increased in brain after illumination, and improved analgesic effects. Excitation of pheophorbide at red light produces ROS to open BBB, help NT enter brain, and enhance its central action. This research provides a new method for drug across BBB to improve its central role. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Access to Strong Opioid Analgesics in the Context of Legal and Regulatory Barriers in Eleven Central and Eastern European Countries.

    Science.gov (United States)

    Vranken, Marjolein J M; Mantel-Teeuwisse, Aukje K; Schutjens, Marie-Hélène D B; Scholten, Willem K; Jünger, Saskia; Medic, Dr Rer; Leufkens, Hubert G M

    2018-04-06

    In 2011-2013, >95% of the global opioid analgesics consumption occurred in three regions, accounting for 15% of the world population. Despite abundant literature on barriers to access, little is known on the correlation between actual access to opioid analgesics and barriers to access, including legal and regulatory barriers. This study aimed to evaluate the correlation between access to strong opioid analgesics and barriers to access in national legislation and regulations in 11 central and eastern European countries that participated in the Access to Opioid Medication in Europe (ATOME) project. Two variables were contrasted to assess their correlation: the country level of access to strong opioid analgesics indicated by the Adequacy of Consumption Measure (ACM) and the number of potential legal and regulatory barriers identified by an external review of legislation and regulations. A linear correlation was evaluated using a squared linear correlation coefficient. Evaluation of the correlation between the ACM and the number of potential barriers produces an R 2 value of 0.023 and a correlation plot trend line gradient of -0.075, indicating no correlation between access to strong opioid analgesics and the number of potential barriers in national legislation and regulations in the countries studied. No correlation was found, which indicates that other factors besides potential legal and regulatory barriers play a critical role in withholding prescribers and patients essential pain medication in the studied countries. More research is needed toward better understanding of the complex interplay of factors that determine access to strong opioid analgesics.

  1. Breaking barriers and halting rupture: the 2016 Amatrice-Visso-Castelluccio earthquake sequence, central Italy

    Science.gov (United States)

    Gregory, L. C.; Walters, R. J.; Wedmore, L. N. J.; Craig, T. J.; McCaffrey, K. J. W.; Wilkinson, M. W.; Livio, F.; Michetti, A.; Goodall, H.; Li, Z.; Chen, J.; De Martini, P. M.

    2017-12-01

    In 2016 the Central Italian Apennines was struck by a sequence of normal faulting earthquakes that ruptured in three separate events on the 24th August (Mw 6.2), the 26th Oct (Mw 6.1), and the 30th Oct (Mw 6.6). We reveal the complex nature of the individual events and the time-evolution of the sequence using multiple datasets. We will present an overview of the results from field geology, satellite geodesy, GNSS (including low-cost short baseline installations), and terrestrial laser scanning (TLS). Sequences of earthquakes of mid to high magnitude 6 are common in historical and seismological records in Italy and other similar tectonic settings globally. Multi-fault rupture during these sequences can occur in seconds, as in the M 6.9 1980 Irpinia earthquake, or can span days, months, or years (e.g. the 1703 Norcia-L'Aquila sequence). It is critical to determine why the causative faults in the 2016 sequence did not rupture simultaneously, and how this relates to fault segmentation and structural barriers. This is the first sequence of this kind to be observed using modern geodetic techniques, and only with all of the datasets combined can we begin to understand how and why the sequence evolved in time and space. We show that earthquake rupture both broke through structural barriers that were thought to exist, but was also inhibited by a previously unknown structure. We will also discuss the logistical challenges in generating datasets on the time-evolving sequence, and show how rapid response and international collaboration within the Open EMERGEO Working Group was critical for gaining a complete picture of the ongoing activity.

  2. Dasatinib crosses the blood-brain barrier and is an efficient therapy for central nervous system philadelphia chromosome positive leukemia

    NARCIS (Netherlands)

    K. Porkka (Kimmo); P. Koskenvesa (Perttu); T. Lundan (Tuija); J. Rimpiläinen (Johanna); S. Mustjoki (Satu); R. Smykla (Richard); R. Wild (Robert); R. Luo (Roger); M. Arnan (Montserrat); B. Brethon (Benoit); L. Eccersley (Lydia); H. Hjorth-Hansen (Henrik); M. Höglund (Martin); H. Klamova (Hana); H. Knutsen (Håvar); S. Parikh (Suhag); E. Raffoux (Emmanuel); F. Gruber (Franz); F. Brito-Babapulle (Finella); H. Dombret (Hervé); R.F. Duarte (Rafael); E. Elonen (Erkki); R. Paquette (Ron); C.M. Zwaan (Christian Michel); F.Y.F. Lee (Francis)

    2008-01-01

    textabstractAlthough imatinib, a BCR-ABL tyrosine kinase inhibitor, is used to treat acute Philadelphia chromosome-positive (Ph+) leukemia, it does not prevent central nervous system (CNS) relapses resulting from poor drug penetration through the blood-brain barrier. Imatinib and dasatinib (a

  3. Antiseptic barrier cap effective in reducing central line-associated bloodstream infections: A systematic review and meta-analysis.

    Science.gov (United States)

    Voor In 't Holt, Anne F; Helder, Onno K; Vos, Margreet C; Schafthuizen, Laura; Sülz, Sandra; van den Hoogen, Agnes; Ista, Erwin

    2017-04-01

    Microorganisms can intraluminally access a central venous catheter via the catheter hub. The catheter hub should be appropriately disinfected to prevent central line-associated bloodstream infections (CLABSIs). However, compliance with the time-consuming manual disinfection process is low. An alternative is the use of an antiseptic barrier cap, which cleans the catheter hub by continuous passive disinfection. To compare the effects of antiseptic barrier cap use and manual disinfection on the incidence of CLABSIs. Systematic review and meta-analysis. We systematically searched Embase, Medline Ovid, Web-of-science, CINAHL EBSCO, Cochrane Library, PubMed Publisher and Google Scholar until May 10, 2016. The primary outcome, reduction in CLABSIs per 1000 catheter-days, expressed as an incidence rate ratio (IRR), was analyzed with a random effects meta-analysis. Studies were included if 1) conducted in a hospital setting, 2) used antiseptic barrier caps on hubs of central lines with access to the bloodstream and 3) reported the number of CLABSIs per 1000 catheter-days when using the barrier cap and when using manual disinfection. A total of 1537 articles were identified as potentially relevant and after exclusion of duplicates, 953 articles were screened based on title and abstract; 18 articles were read full text. Eventually, nine studies were included in the systematic review, and seven of these nine in the random effects meta-analysis. The pooled IRR showed that use of the antiseptic barrier cap was effective in reducing CLABSIs (IRR=0.59, 95% CI=0.45-0.77, Pantiseptic barrier cap is associated with a lower incidence CLABSIs and is an intervention worth adding to central-line maintenance bundles. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. INTEGRATING GEOPHYSICS, GEOLOGY, AND HYDROLOGY TO DETERMINE BEDROCK GEOMETRY CONTROLS ON THE ORIGIN OF ISOLATED MEADOW COMPLEXES WITHIN THE CENTRAL GREAT BASIN, NEVADA

    Science.gov (United States)

    Riparian meadow complexes found in mountain ranges of the Central Great Basin physiographic region (western United States) are of interest to researchers as they contain significant biodiversity relative to the surrounding basin areas. These meadow complexes are currently degradi...

  5. HYDROGEOMORPHIC SETTING, CHARACTERISTICS, AND RESPONSE TO STREAM INCISION OF MONTANA RIPARIAN MEADOWS IN THE CENTRAL GREAT BASIN--IMPLICATIONS FOR RESTORATION

    Science.gov (United States)

    Riparian wet meadow complexes in the mountains of the central Great Basin are scarce, ecologically important systems that are threatened by stream incision. An interdisciplinary group has investigated 1) the origin, characteristics, and controls on the evolution of these riparian...

  6. Nanowired Drug Delivery Across the Blood-Brain Barrier in Central Nervous System Injury and Repair.

    Science.gov (United States)

    Sharma, Aruna; Menon, Preeti; Muresanu, Dafin F; Ozkizilcik, Asya; Tian, Z Ryan; Lafuente, José V; Sharma, Hari S

    2016-01-01

    The blood-brain barrier (BBB) is a physiological regulator of transport of essential items from blood to brain for the maintenance of homeostasis of the central nervous system (CNS) within narrow limits. The BBB is also responsible for export of harmful or metabolic products from brain to blood to keep the CNS fluid microenvironment healthy. However, noxious insults to the brain caused by trauma, ischemia or environmental/chemical toxins alter the BBB function to small as well as large molecules e.g., proteins. When proteins enter the CNS fluid microenvironment, development of brain edema occurs due to altered osmotic balance between blood and brain. On the other hand, almost all neurodegenerative diseases and traumatic insults to the CNS and subsequent BBB dysfunction lead to edema formation and cell injury. To treat these brain disorders suitable drug therapy reaching their brain targets is needed. However, due to edema formation or only a focal disruption of the BBB e.g., around brain tumors, many drugs are unable to reach their CNS targets in sufficient quantity. This results in poor therapeutic outcome. Thus, new technology such as nanodelivery is needed for drugs to reach their CNS targets and be effective. In this review, use of nanowires as a possible novel tool to enhance drug delivery into the CNS in various disease models is discussed based on our investigations. These data show that nanowired delivery of drugs may have superior neuroprotective ability to treat several CNS diseases effectively indicating their role in future therapeutic strategies.

  7. Middle to Late Ordovician faunal studies from central Australia and Tasmania during the Great Ordovician Biodiversification Event

    DEFF Research Database (Denmark)

    Jakobsen, Kristian Grube

    A profound transformation of the marine biosphere took place during the Great Ordovician Biodiversification Event (GOBE), recognized as the longest interval of sustained biodiversification in the history of life. Successions through the Middle Ordovician Stairway Sandstone of the Amadeus Basin......, but the diversity is generally relatively low. The bivalves are the most dominant and diverse group in the central Australian fauna, whereas the brachiopods are the most dominant and diverse group in the Tasmanian fauna. Thirteen trilobite, five brachiopod, four conodont and 22 mollusc taxa have been documented......, but the preservation and low number of specimens prevent formal definition of additional new taxa. Although highly endemic at species level, the investigated brachiopod, trilobite and mollusc faunas display a high degree of overall similarity at generic level with Middle Ordovician faunas from North China. Other...

  8. Water use benefit index as a tool for community-based monitoring of water related trends in the Great Barrier Reef region

    Science.gov (United States)

    Smajgl, A.; Larson, S.; Hug, B.; De Freitas, D. M.

    2010-12-01

    SummaryThis paper presents a tool for documenting and monitoring water use benefits in the Great Barrier Reef catchments that allows temporal and spatial comparison along the region. Water, water use benefits and water allocations are currently receiving much attention from Australian policy makers and conservation practitioners. Because of the inherent complexity and variability in water quality, it is essential that scientific information is presented in a meaningful way to policy makers, managers and ultimately, to the general public who have to live with the consequences of the decisions. We developed an inexpensively populated and easily understandable water use benefit index as a tool for community-based monitoring of water related trends in the Great Barrier Reef region. The index is developed based on a comparative list of selected water-related indices integrating attributes across physico-chemical, economic, social, and ecological domains currently used in the assessment of water quality, water quantity and water use benefits in Australia. Our findings indicate that the proposed index allows the identification of water performance indicators by temporal and spatial comparisons. Benefits for decision makers and conservation practitioners include a flexible way of prioritization towards the domain with highest concern. The broader community benefits from a comprehensive and user-friendly tool, communicating changes in water quality trends more effectively.

  9. Fusing MODIS with Landsat 8 data to downscale weekly normalized difference vegetation index estimates for central Great Basin rangelands, USA

    Science.gov (United States)

    Boyte, Stephen; Wylie, Bruce K.; Rigge, Matthew B.; Dahal, Devendra

    2018-01-01

    Data fused from distinct but complementary satellite sensors mitigate tradeoffs that researchers make when selecting between spatial and temporal resolutions of remotely sensed data. We integrated data from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor aboard the Terra satellite and the Operational Land Imager sensor aboard the Landsat 8 satellite into four regression-tree models and applied those data to a mapping application. This application produced downscaled maps that utilize the 30-m spatial resolution of Landsat in conjunction with daily acquisitions of MODIS normalized difference vegetation index (NDVI) that are composited and temporally smoothed. We produced four weekly, atmospherically corrected, and nearly cloud-free, downscaled 30-m synthetic MODIS NDVI predictions (maps) built from these models. Model results were strong with R2 values ranging from 0.74 to 0.85. The correlation coefficients (r ≥ 0.89) were strong for all predictions when compared to corresponding original MODIS NDVI data. Downscaled products incorporated into independently developed sagebrush ecosystem models yielded mixed results. The visual quality of the downscaled 30-m synthetic MODIS NDVI predictions were remarkable when compared to the original 250-m MODIS NDVI. These 30-m maps improve knowledge of dynamic rangeland seasonal processes in the central Great Basin, United States, and provide land managers improved resource maps.

  10. Silver deposition in the central nervous system and the hematoencephalic barrier studied with the electron microscope.

    Science.gov (United States)

    VAN BREEMEN, V L; CLEMENTE, C D

    1955-03-01

    For the purpose of studying the hematoencephalic barrier as it is concerned with silver circulating in the blood stream, silver nitrate was vitally administered to rats in their drinking water over periods of 6 to 8 months. The cerebrum, cerebellum, medulla, area postrema, and choroid plexus were prepared for light and electron microscopy. Silver deposition was found in the perivascular spaces in the choroid plexus, area postrema, in the medulla surrounding the area postrema, and in minute quantities in the cerebrum, cerebellum, and most of the medulla. Two levels of the hematoencephalic barrier were apparently demonstrated in our investigations. The endothelial linings of the vessels in the cerebrum, cerebellum, and medulla constitute the first threshold of the hematoencephalic barrier (specifically here, blood-brain barrier). The cell membranes adjacent to the perivascular spaces form the second threshold, as follows:-the neuroglial cell membranes in the cerebrum, cerebellum, and medulla (blood-brain barrier); the membranes of the neuroglial cells in the area postrema (blood-brain barrier); and the membranes of the epithelial cells of the choroid plexus (blood-cerebrospinal fluid barrier). This study deals with silver deposition and does not infer that the penetration of ionic silver, if present in the blood stream, would necessarily be limited to the regions described. Bleb-like structures were observed to cover the epithelial cell surfaces in the choroid plexus. They may be cellular projections increasing the cell surface area or they may be secretory droplets.

  11. Architecture of an Upper Jurassic barrier island sandstone reservoir, Danish Central Graben:

    DEFF Research Database (Denmark)

    Johannessen, Peter N.; Nielsen, Lars H.; Nielsen, Lars

    2010-01-01

    An unusually thick (c. 88 m), transgressive barrier island and shoreface sandstone succession characterizes the Upper Jurassic Heno Formation reservoir of the Freja oil field situated on the boundary of Denmark and Norway. The development and preservation of such thick transgressive barrier island...... sands is puzzling since a barrier island typically migrates landwards during transgression and only a thin succession of back-barrier and shoreface sands is preserved. Investigation of the development and geometry of the Freja reservoir sandstones is problematic since the reservoir is buried c. 5 km...... and seismic resolution is inadequate for architectural analysis. Description of the reservoir sandstone bodies is thus based on sedimentological interpretation and correlation of seven wells, of which five were cored. Palaeotopography played a major role in the position and preservation of the thick reservoir...

  12. Heat flow in Railroad Valley, Nevada and implications for geothermal resources in the south-central Great Basin

    Science.gov (United States)

    Williams, C.F.; Sass, J.H.

    2006-01-01

    The Great Basin is a province of high average heat flow (approximately 90 mW m-2), with higher values characteristic of some areas and relatively low heat flow (characteristic of an area in south-central Nevada known as the Eureka Low. There is hydrologie and thermal evidence that the Eureka Low results from a relatively shallow, hydrologically controlled heat sink associated with interbasin water flow in the Paleozoic carbonate aquifers. Evaluating this hypothesis and investigating the thermal state of the Eureka Low at depth is a high priority for the US Geological Survey as it prepares a new national geothermal resource assessment. Part of this investigation is focused on Railroad Valley, the site of the largest petroleum reservoirs in Nevada and one of the few locations within the Eureka Low with a known geothermal system. Temperature and thermal conductivity data have been acquired from wells in Railroad Valley in order to determine heat flow in the basin. The results reveal a complex interaction of cooling due to shallow ground-water flow, relatively low (49 to 76 mW m-2) conductive heat flow at depth in most of the basin, and high (up to 234 mW m-2) heat flow associated with the 125??C geothermal system that encompasses the Bacon Flat and Grant Canyon oil fields. The presence of the Railroad Valley geothermal resource within the Eureka Low may be reflect the absence of deep ground-water flow sweeping heat out of the basin. If true, this suggests that other areas in the carbonate aquifer province may contain deep geothermal resources that are masked by ground-water flow.

  13. Variation in the health and biochemical condition of the coral Acropora tenuis along two water quality gradients on the Great Barrier Reef, Australia.

    Science.gov (United States)

    Rocker, Melissa M; Francis, David S; Fabricius, Katharina E; Willis, Bette L; Bay, Line K

    2017-06-30

    This study explores how plasticity in biochemical attributes, used as indicators of health and condition, enables the coral Acropora tenuis to respond to differing water quality regimes in inshore regions of the Great Barrier Reef. Health attributes were monitored along a strong and weak water quality gradient, each with three reefs at increasing distances from a major river source. Attributes differed significantly only along the strong gradient; corals grew fastest, had the least dense skeletons, highest symbiont densities and highest lipid concentrations closest to the river mouth, where water quality was poorest. High nutrient and particulate loads were only detrimental to skeletal density, which decreased as linear extension increased, highlighting a trade-off. Our study underscores the importance of assessing multiple health attributes in coral reef monitoring. For example, autotrophic indices are poor indicators of coral health and condition, but improve when combined with attributes like lipid content and biomass. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Insights into the history and timing of post-European land use disturbance on sedimentation rates in catchments draining to the Great Barrier Reef.

    Science.gov (United States)

    Bartley, Rebecca; Thompson, Chris; Croke, Jacky; Pietsch, Tim; Baker, Brett; Hughes, Kate; Kinsey-Henderson, Anne

    2018-06-01

    Sediment runoff has been cited as a major contributor to the declining health of the Great Barrier Reef (GBR), however, climate and land use drivers have not been jointly evaluated. This study used alluvial archives from fluvial benches in two tributaries of the Upper Burdekin catchment together with the best available land use history and climate proxy records to provide insights into the timing of depositional events in this region over the past 500 years. This study suggests that mining and the increased runoff variability in the latter half of the nineteenth century are the likely sources of the original excess sediment that was used to build the bench features in these catchments. Grazing also contributed to increased bench sedimentation prior to 1900, however, the contribution of grazing was likely more significant in the second half of the 20th century, and continues to be a dominant land use contributor today. Copyright © 2018 Elsevier Ltd. All rights reserved.

  15. Predictable pollution: an assessment of weather balloons and associated impacts on the marine environment--an example for the Great Barrier Reef, Australia.

    Science.gov (United States)

    O'Shea, Owen R; Hamann, Mark; Smith, Walter; Taylor, Heidi

    2014-02-15

    Efforts to curb pollution in the marine environment are covered by national and international legislation, yet weather balloons are released into the environment with no salvage agenda. Here, we assess impacts associated with weather balloons in the Great Barrier Reef World Heritage Area (GBRWHA). We use modeling to assess the probability of ocean endpoints for released weather balloons and predict pathways post-release. In addition, we use 21 months of data from beach cleanup events to validate our results and assess the abundance and frequency of weather balloon fragments in the GBRWHA. We found between 65% and 70% of balloons land in the ocean and ocean currents largely determine final endpoints. Beach cleanup data revealed 2460 weather balloon fragments were recovered from 24 sites within the GBRWHA. This is the first attempt to quantify this problem and these data will add support to a much-needed mitigation strategy for weather balloon waste. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Sense of place as a determinant of people's attitudes towards the environment: implications for natural resources management and planning in the Great Barrier Reef, Australia.

    Science.gov (United States)

    Larson, Silva; De Freitas, Debora M; Hicks, Christina C

    2013-03-15

    Integrating people's values and perceptions into planning is essential for the successful management of natural resources. However, successful implementation of natural resources management decisions on the ground is a complex task, which requires a comprehensive understanding of a system's social and ecological linkages. This paper investigates the relationship between sense of place and people's attitudes towards their natural environment. Sense of place contributes towards shaping peoples' beliefs, values and commitments. Here, we set out to explore how these theoretical contributions can be operationalized for natural resources management planning in the Great Barrier Reef region of Australia. We hypothesise that the region's diverse range of natural resources, conservation values and management pressures might be reflected in people's attachment to place. To tests this proposition, variables capturing socio-demographics, personal wellbeing and a potential for sense of place were collected via mail-out survey of 372 residents of the region, and tested for relationships using multivariate regression and redundancy orientation analyses. Results indicate that place of residence within the region, involvement in community activities, country of birth and the length of time respondents lived in the region are important determinants of the values assigned to factors related to the natural environment. This type of information is readily available from National Census and thus could be incorporated into the planning of community engagement strategies early in the natural resources management planning process. A better understanding of the characteristics that allow sense of place meanings to develop can facilitate a better understanding of people's perceptions towards environmental and biodiversity issues. We suggest that the insights gained from this study can benefit environmental decision making and planning in the Great Barrier Reef region; and that sense of place

  17. Global warming likely reduces crop yield and water availability of the dryland cropping systems in the U.S. central Great Plains

    Science.gov (United States)

    We investigated impacts of GCM-projected climate change on dryland crop rotations of wheat-fallow and wheat-corn-fallow in the Central Great Plains (Akron in Colorado, USA) using the CERES 4.0 crop modules in RZWQM2. The climate change scenarios for CO2, temperature, and precipitation were produced ...

  18. A Systematic Content Analysis of Policy Barriers Impeding Access to Opioid Medication in Central and Eastern Europe: Results of ATOME.

    Science.gov (United States)

    Larjow, Eugenia; Papavasiliou, Evangelia; Payne, Sheila; Scholten, Willem; Radbruch, Lukas

    2016-01-01

    Reliable access to opioid medication is critical to delivering effective pain management, adequate treatment of opioid dependence, and quality palliative care. However, more than 80% of the world population is estimated to be inadequately treated for pain because of difficulties in accessing opioids. Although barriers to opioid access are primarily associated with restrictive laws, regulations, and licensing requirements, a key problem that significantly limits opioid access relates to policy constraints. To identify and explore policy barriers to opioid access in 12 Eastern and Central European countries involved in the Access to Opioid Medication in Europe project, funded by the European Community's Seventh Framework (FP7/2007-2013, no. 222994) Programme. A systematic content analysis of texts retrieved from documents (e.g., protocols of national problem analyses, strategic planning worksheets, and executive summaries) compiled, reviewed, approved, and submitted by either the Access to Opioid Medication in Europe consortium or the national country teams (comprising experts in pain management, harm reduction, and palliative care) between September 2011 and April 2014 was performed. Twenty-five policy barriers were identified (e.g., economic crisis, bureaucratic issues, lack of training initiatives, stigma, and discrimination), classified under four predetermined categories (financial/economic aspects and governmental support, formularies, education and training, and societal attitudes). Key barriers related to issues of funding allocation, affordability, knowledge, and fears associated with opioids. Reducing barriers and improving access to opioids require policy reform at the governmental level with a set of action plans being formulated and concurrently implemented and aimed at different levels of social, education, and economic policy change. Copyright © 2016 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.

  19. Socio-Structural Barriers, Protective Factors, and HIV Risk Among Central-Asian Female Migrants in Moscow

    Directory of Open Access Journals (Sweden)

    Christopher Zabrocki

    2013-07-01

    Full Text Available Objective: This study aimed to build formative knowledge on socio-structural barriers, protective factors, and HIV sexual risk amongst Central-Asian female migrants in Moscow. Methods: Data collection included ethnographic interviews in Moscow with a purposive sample of 30 unmarried female migrants, 15 from Kyrgyzstan and 15 from Tajikistan. Results: Study participants reported difficulties with acquiring documents for legal status, financial insecurity, discrimination, sexual harassment, and lack of support. Based on analysis of the cases, one pathway linked lack of legal documentation and instrumental support with elevated sexual risk. Another pathways linked traditional cultural attitudes with both no and moderate sexual risk. Conclusion: Future HIV prevention efforts with Central Asian female migrants in Moscow should be multilevel and include: increasing HIV and prevention knowledge and skills, promoting condom use with regular partners, identifying and supporting cultural attitudes that protect against HIV sexual risk behaviors, facilitating legal status, building community support, and increasing economic options.

  20. Mental Health Attitudes and Beliefs in a Community Sample on the Central Coast in Australia: Barriers to Help Seeking.

    Science.gov (United States)

    Coates, Dominiek; Saleeba, Christine; Howe, Deborah

    2018-03-27

    There continues to be call for greater community awareness actions and strategies to reduce stigma and enhance mental health literacy nationally and internationally. To identify local barriers to help-seeking and perceptions around stigma, we developed a 'mental health attitudes and beliefs' survey which was administered at a range of community events on the Central Coast in New South Wales, Australia. The aim was for the results of this survey to inform the development of strategies that enhance local help-seeking behaviours that are sensitive to the role of age, gender and Indigenous status. People who approached our Mental Health Information stall were invited to complete the survey and 282 individuals completed the survey. The data was analysed descriptively with a focus on comparing subgroups based on age, gender, Indigenous status, and previous service access or experience of mental illness. Cost, stigma and mental health literacy were found to be prominent barriers to help-seeking for the overall cohort; however, the ways in which or extent to which these barriers impact on help seeking varied between subgroups. A discussion of these differences and their implications for practice is the focus of this paper.

  1. Endothelial β-Catenin Signaling Is Required for Maintaining Adult Blood-Brain Barrier Integrity and Central Nervous System Homeostasis.

    Science.gov (United States)

    Tran, Khiem A; Zhang, Xianming; Predescu, Dan; Huang, Xiaojia; Machado, Roberto F; Göthert, Joachim R; Malik, Asrar B; Valyi-Nagy, Tibor; Zhao, You-Yang

    2016-01-12

    The blood-brain barrier (BBB) formed by brain endothelial cells interconnected by tight junctions is essential for the homeostasis of the central nervous system. Although studies have shown the importance of various signaling molecules in BBB formation during development, little is known about the molecular basis regulating the integrity of the adult BBB. Using a mouse model with tamoxifen-inducible endothelial cell-restricted disruption of ctnnb1 (iCKO), we show here that endothelial β-catenin signaling is essential for maintaining BBB integrity and central nervous system homeostasis in adult mice. The iCKO mice developed severe seizures accompanied by neuronal injury, multiple brain petechial hemorrhages, and central nervous system inflammation, and all had postictal death. Disruption of endothelial β-catenin induced BBB breakdown and downregulation of the specific tight junction proteins claudin-1 and -3 in adult brain endothelial cells. The clinical relevance of the data is indicated by the observation of decreased expression of claudin-1 and nuclear β-catenin in brain endothelial cells of hemorrhagic lesions of hemorrhagic stroke patients. These results demonstrate the prerequisite role of endothelial β-catenin in maintaining the integrity of adult BBB. The results suggest that BBB dysfunction secondary to defective β-catenin transcription activity is a key pathogenic factor in hemorrhagic stroke, seizure activity, and central nervous system inflammation. © 2015 American Heart Association, Inc.

  2. Unmasking the Role of Uptake Transporters for Digoxin Uptake Across the Barriers of the Central Nervous System in Rat

    Directory of Open Access Journals (Sweden)

    Kunal S Taskar

    2017-03-01

    Full Text Available The role of uptake transporter (organic anion–transporting polypeptide [Oatp] in the disposition of a P-glycoprotein (P-gp substrate (digoxin at the barriers of central nervous system, namely, the blood-brain barrier (BBB, blood-spinal cord barrier (BSCB, and brain-cerebrospinal fluid barrier (BCSFB, was studied using rat as a preclinical species. In vivo chemical inhibition of P-gp and Oatp was achieved using elacridar and rifampicin, respectively. Our findings show that (1 digoxin had a low brain-to-plasma concentration ratio (B/P (0.07 in rat; (2 in the presence of elacridar, the B/P of digoxin increased by about 12-fold; (3 rifampicin administration alone did not change the digoxin B/P significantly when compared with digoxin B/P alone; (4 rifampicin administration along with elacridar resulted only in 6-fold increase in the B/P of digoxin; (5 similar fold changes and trends were seen with the spinal cord-to-plasma concentration ratio of digoxin, indicating the similarity between BBB and the BSCB; and (6 unlike BBB and BSCB, the presence of rifampicin further increased the cerebrospinal fluid-to-plasma concentration ratio (CSF/P for digoxin, suggesting a differential orientation of the uptake transporters at the BCSFB (CSF to blood compared with the BBB (blood to brain. The observations for digoxin uptake, at least at the BBB and the BSCB, advocate the importance of uptake transporters (Oatps. However, the activity of such uptake transporters became evident only after inhibition of the efflux transporter (P-gp.

  3. Linking the Local and the Global. What Today’s Environmental Humanities Movement Can Learn from Their Predecessor’s Successful Leadership of the 1965–1975 War to Save the Great Barrier Reef

    Directory of Open Access Journals (Sweden)

    Iain McCalman

    2017-10-01

    Full Text Available For a decade from 1965–1975, an Australian poet, Judith Wright, and a Reef artist, John Busst, played a major role in helping to save the Great Barrier Reef. The Queensland State Government had declared its intention of mining up to eighty percent of the Reef’s corals for oil, gas, fertiliser and cement. The campaign of resistance led by these two humanists, in alliance with a forester, Dr. Len Webb, contributed substantively to the establishment of the Great Barrier Reef Marine Park in 1975 and to then to the Reef’s World Heritage listing in 1983 as ‘the most impressive marine environment in the world’. This paper explains the challenges facing today’s environmental scholars and activists as they attempt to replicate the success of their 1970s predecessors in helping to save the Great Barrier Reef from even graver and more immediate threats to its survival.

  4. Barriers to Coverage of Transborder Environmental Issues in the Ferghana Valley of Central Asia

    Science.gov (United States)

    Freedman, Eric

    2014-01-01

    Three former Soviet republics occupy Central Asia's Ferghana Valley, a region of serious transborder environmental problems, especially ones that involve water and energy. Most news organizations in Kyrgyzstan, Tajikistan, and Uzbekistan provide little in-depth coverage of these issues. Journalists in one country usually do not seek news sources…

  5. Multilevel stigma as a barrier to HIV testing in Central Asia: a context quantified.

    Science.gov (United States)

    Smolak, Alex; El-Bassel, Nabila

    2013-10-01

    Central Asia is experiencing one of the fastest growing HIV epidemics in the world, with some areas' infection rates doubling yearly since 2000. This study examines the impact of multilevel stigma (individual, family, and community) on uptake of HIV testing and receipt of HIV testing results among women in Central Asia. The sample consists of 38,884 ever-married, Central Asian women between the ages of 15 and 49. Using multilevel modeling (MLM), HIV stigma variables at the individual, family, and community levels were used to assess the significance of differences in HIV testing and receipt of HIV test results among participants while adjusting for possible confounding factors, such as age, wealth, and education. MLM results indicate that HIV stigma is significantly associated with decreased HIV testing uptake at the individual, family, and community levels and with a decrease in receipt at the community level. A one standard deviation increase in individual, family, and community level composite stigma score was associated with a respective 49 %, 59 %, and 94 % (p hinder HIV testing uptake and at the community level to hinder receipt. These findings have important interventions implications to improve uptake of HIV testing and receipt of HIV test results.

  6. AN INTEGRATED, SCIENCE-BASED APPROACH TO MANAGING AND RESTORING UPLAND RIPARIAN MEADOWS IN THE GREAT BASIN OF CENTRAL NEVADA

    Science.gov (United States)

    Riparian corridor and meadow ecosystems in upland watersheds are of local and regional importance in the Great Basin. Covering only 1-3% of the total land area, these ecosystems contain a disproportionally large percentage of the region's biodiversity. Stream incision is a major ...

  7. Microsatellites Reveal Genetic Homogeneity among Outbreak Populations of Crown-of-Thorns Starfish (Acanthaster cf. solaris) on Australia’s Great Barrier Reef

    KAUST Repository

    Harrison, Hugo

    2017-03-10

    Specific patterns in the initiation and spread of reef-wide outbreaks of crown-of-thorns starfish are important, both to understand potential causes (or triggers) of outbreaks and to develop more effective and highly targeted management and containment responses. Using analyses of genetic diversity and structure (based on 17 microsatellite loci), this study attempted to resolve the specific origin for recent outbreaks of crown-of-thorns on Australia’s Great Barrier Reef (GBR). We assessed the genetic structure amongst 2705 starfish collected from 13 coral reefs in four regions that spanned ~1000 km of the GBR. Our results indicate that populations sampled across the full length of the GBR are genetically homogeneous (G’ST = −0.001; p = 0.948) with no apparent genetic structure between regions. Approximate Bayesian computational analyses suggest that all sampled populations had a common origin and that current outbreaking populations of crown-of-thorns starfish (CoTS) in the Swains are not independent of outbreak populations in the northern GBR. Despite hierarchical sampling and large numbers of CoTS genotyped from individual reefs and regions, limited genetic structure meant we were unable to determine a putative source population for the current outbreak of CoTS on the GBR. The very high genetic homogeneity of sampled populations and limited evidence of inbreeding indicate rapid expansion in population size from multiple, undifferentiated latent populations.

  8. Differences in demographic traits of four butterflyfish species between two reefs of the Great Barrier Reef separated by 1,200 km

    KAUST Repository

    Berumen, Michael L.

    2011-11-16

    Many species demonstrate variation in life history attributes in response to gradients in environmental conditions. For fishes, major drivers of life history variation are changes in temperature and food availability. This study examined large-scale variation in the demography of four species of butterflyfishes (Chaetodon citrinellus, Chaetodon lunulatus, Chaetodon melannotus, and Chaetodon trifascialis) between two locations on Australia\\'s Great Barrier Reef (Lizard Island and One Tree Island, separated by approximately 1,200 km). Variation in age-based demographic parameters was assessed using the re-parameterised von Bertalanffy growth function. All species displayed measurable differences in body size between locations, with individuals achieving a larger adult size at the higher latitude site (One Tree Island) for three of the four species examined. Resources and abundances of the study species were also measured, revealing some significant differences between locations. For example, for C. trifascialis, there was no difference in its preferred resource or in abundance between locations, yet it achieved a larger body size at the higher latitude location, suggesting a response to temperature. For some species, resources and abundances did vary between locations, limiting the ability to distinguish between a demographic response to temperature as opposed to a response to food or competition. Future studies of life histories and demographics at large spatial scales will need to consider the potentially confounding roles of temperature, resource usage and availability, and abundance/competition to disentangle the effects of these environmental variables. © 2011 Springer-Verlag.

  9. The Australian REEFREP System: A Coastal Vessel Traffic Information Service and Ship Reporting System for the Torres Strait Region and the Inner Route of the Great Barrier Reef

    Science.gov (United States)

    MacDonald, John C.

    The new Australian ship reporting system, identifier , will be the core component of a Vessel Traffic Information Service (VTIS) covering the Torres Strait region and the Great Barrier Reef (GBR). It is the first such system to be considered by the International Maritime Organization (IMO) under the terms of the new SOLAS 74 regulation v/8-1, which entered into force on 1 January 1996 and allows for ship reporting systems adopted by the Organization to be made mandatory for all, or certain categories of vessels.The REEFREP system, planned for implementation on 1 January 1997, extends for some 900 n.m. or about 1500 km along the Queensland coastline. It will be a VHF radio-based system with radars covering three selected focal points in the Torres Strait, off Cairns and in the southern approaches to the inner route. The system will provide a capability for a single Ship Reporting Centre to interact with shipping, enabling the provision of improved information on the presence, movements and patterns of shipping in the area and the ability to respond more quickly to an incident or pollution should this occur.An interesting feature and a major factor in the system design is the remoteness of most equipment sites and the limited infrastructure available to support communications and data transmission requiring the application of advanced technology and video transmission, solar power generation and software engineering skills of a high order.

  10. Comparison of retracked coastal altimetry sea levels against high frequency radar on the continental shelf of the Great Barrier Reef, Australia

    Science.gov (United States)

    Idris, Nurul Hazrina; Deng, Xiaoli; Idris, Nurul Hawani

    2017-07-01

    Comparison of Jason-1 altimetry retracked sea levels and high frequency (HF) radar velocity is examined within the region of the Great Barrier Reef, Australia. The comparison between both datasets is not direct because the altimetry derives only the geostrophic component, while the HF radar velocity includes information on both geostrophic and ageostrophic components, such as tides and winds. The comparison of altimetry and HF radar data is performed based on the parameter of surface velocity inferred from both datasets. The results show that 48% (10 out of 21 cases) of data have high (≥0.5) spatial correlation. The mean of spatial correlation for all 21 cases is 0.43. This value is within the range (0.42 to 0.5) observed by other studies. Low correlation is observed due to disagreement in the trend of velocity signals in which sometimes they have contradictions in the signal direction and the position of the peak is shifted. In terms of standard deviation of difference and root mean square error, both datasets show reasonable agreement with ≤2.5 cm s-1.

  11. Microsatellites Reveal Genetic Homogeneity among Outbreak Populations of Crown-of-Thorns Starfish (Acanthaster cf. solaris) on Australia’s Great Barrier Reef

    KAUST Repository

    Harrison, Hugo; Pratchett, Morgan; Messmer, Vanessa; Saenz-Agudelo, Pablo; Berumen, Michael L.

    2017-01-01

    Specific patterns in the initiation and spread of reef-wide outbreaks of crown-of-thorns starfish are important, both to understand potential causes (or triggers) of outbreaks and to develop more effective and highly targeted management and containment responses. Using analyses of genetic diversity and structure (based on 17 microsatellite loci), this study attempted to resolve the specific origin for recent outbreaks of crown-of-thorns on Australia’s Great Barrier Reef (GBR). We assessed the genetic structure amongst 2705 starfish collected from 13 coral reefs in four regions that spanned ~1000 km of the GBR. Our results indicate that populations sampled across the full length of the GBR are genetically homogeneous (G’ST = −0.001; p = 0.948) with no apparent genetic structure between regions. Approximate Bayesian computational analyses suggest that all sampled populations had a common origin and that current outbreaking populations of crown-of-thorns starfish (CoTS) in the Swains are not independent of outbreak populations in the northern GBR. Despite hierarchical sampling and large numbers of CoTS genotyped from individual reefs and regions, limited genetic structure meant we were unable to determine a putative source population for the current outbreak of CoTS on the GBR. The very high genetic homogeneity of sampled populations and limited evidence of inbreeding indicate rapid expansion in population size from multiple, undifferentiated latent populations.

  12. Ultrasound-mediated blood-brain barrier disruption for targeted drug delivery in the central nervous system

    Science.gov (United States)

    Aryal, Muna; Arvanitis, Costas D.; Alexander, Phillip M.; McDannold, Nathan

    2014-01-01

    The physiology of the vasculature in the central nervous system (CNS), which includes the blood-brain barrier (BBB) and other factors, complicates the delivery of most drugs to the brain. Different methods have been used to bypass the BBB, but they have limitations such as being invasive, non-targeted or requiring the formulation of new drugs. Focused ultrasound (FUS), when combined with circulating microbubbles, is a noninvasive method to locally and transiently disrupt the BBB at discrete targets. This review provides insight on the current status of this unique drug delivery technique, experience in preclinical models, and potential for clinical translation. If translated to humans, this method would offer a flexible means to target therapeutics to desired points or volumes in the brain, and enable the whole arsenal of drugs in the CNS that are currently prevented by the BBB. PMID:24462453

  13. Coral-macroalgal phase shifts or reef resilience: links with diversity and functional roles of herbivorous fishes on the Great Barrier Reef

    Science.gov (United States)

    Cheal, A. J.; MacNeil, M. Aaron; Cripps, E.; Emslie, M. J.; Jonker, M.; Schaffelke, B.; Sweatman, H.

    2010-12-01

    Changes from coral to macroalgal dominance following disturbances to corals symbolize the global degradation of coral reefs. The development of effective conservation measures depends on understanding the causes of such phase shifts. The prevailing view that coral-macroalgal phase shifts commonly occur due to insufficient grazing by fishes is based on correlation with overfishing and inferences from models and small-scale experiments rather than on long-term quantitative field studies of fish communities at affected and resilient sites. Consequently, the specific characteristics of herbivorous fish communities that most promote reef resilience under natural conditions are not known, though this information is critical for identifying vulnerable ecosystems. In this study, 11 years of field surveys recorded the development of the most persistent coral-macroalgal phase shift (>7 years) yet observed on Australia’s Great Barrier Reef (GBR). This shift followed extensive coral mortality caused by thermal stress (coral bleaching) and damaging storms. Comparisons with two similar reefs that suffered similar disturbances but recovered relatively rapidly demonstrated that the phase shift occurred despite high abundances of one herbivore functional group (scraping/excavating parrotfishes: Labridae). However, the shift was strongly associated with low fish herbivore diversity and low abundances of algal browsers (predominantly Siganidae) and grazers/detritivores (Acanthuridae), suggesting that one or more of these factors underpin reef resilience and so deserve particular protection. Herbivorous fishes are not harvested on the GBR, and the phase shift was not enhanced by unusually high nutrient levels. This shows that unexploited populations of herbivorous fishes cannot ensure reef resilience even under benign conditions and suggests that reefs could lose resilience under relatively low fishing pressure. Predictions of more severe and widespread coral mortality due to global

  14. The physiological response of two green calcifying algae from the Great Barrier Reef towards high dissolved inorganic and organic carbon (DIC and DOC availability.

    Directory of Open Access Journals (Sweden)

    Friedrich Wilhelm Meyer

    Full Text Available Increasing dissolved inorganic carbon (DIC concentrations associated with ocean acidification can affect marine calcifiers, but local factors, such as high dissolved organic carbon (DOC concentrations through sewage and algal blooms, may interact with this global factor. For calcifying green algae of the genus Halimeda, a key tropical carbonate producer that often occurs in coral reefs, no studies on these interactions have been reported. These data are however urgently needed to understand future carbonate production. Thus, we investigated the independent and combined effects of DIC (pCO2 402 μatm/ pHtot 8.0 and 996 μatm/ pHtot 7.7 and DOC (added as glucose in 0 and 294 μmol L-1 on growth, calcification and photosynthesis of H. macroloba and H. opuntia from the Great Barrier Reef in an incubation experiment over 16 days. High DIC concentrations significantly reduced dark calcification of H. opuntia by 130 % and led to net dissolution, but did not affect H. macroloba. High DOC concentrations significantly reduced daily oxygen production of H. opuntia and H. macroloba by 78 % and 43 %, respectively, and significantly reduced dark calcification of H. opuntia by 70%. Combined high DIC and DOC did not show any interactive effects for both algae, but revealed additive effects for H. opuntia where the combination of both factors reduced dark calcification by 162 % compared to controls. Such species-specific differences in treatment responses indicate H. opuntia is more susceptible to a combination of high DIC and DOC than H. macroloba. From an ecological perspective, results further suggest a reduction of primary production for Halimeda-dominated benthic reef communities under high DOC concentrations and additional decreases of carbonate accretion under elevated DIC concentrations, where H. opuntia dominates the benthic community. This may reduce biogenic carbonate sedimentation rates and hence the buffering capacity against further ocean

  15. The physiological response of two green calcifying algae from the Great Barrier Reef towards high dissolved inorganic and organic carbon (DIC and DOC) availability.

    Science.gov (United States)

    Meyer, Friedrich Wilhelm; Vogel, Nikolas; Teichberg, Mirta; Uthicke, Sven; Wild, Christian

    2015-01-01

    Increasing dissolved inorganic carbon (DIC) concentrations associated with ocean acidification can affect marine calcifiers, but local factors, such as high dissolved organic carbon (DOC) concentrations through sewage and algal blooms, may interact with this global factor. For calcifying green algae of the genus Halimeda, a key tropical carbonate producer that often occurs in coral reefs, no studies on these interactions have been reported. These data are however urgently needed to understand future carbonate production. Thus, we investigated the independent and combined effects of DIC (pCO2 402 μatm/ pHtot 8.0 and 996 μatm/ pHtot 7.7) and DOC (added as glucose in 0 and 294 μmol L-1) on growth, calcification and photosynthesis of H. macroloba and H. opuntia from the Great Barrier Reef in an incubation experiment over 16 days. High DIC concentrations significantly reduced dark calcification of H. opuntia by 130 % and led to net dissolution, but did not affect H. macroloba. High DOC concentrations significantly reduced daily oxygen production of H. opuntia and H. macroloba by 78 % and 43 %, respectively, and significantly reduced dark calcification of H. opuntia by 70%. Combined high DIC and DOC did not show any interactive effects for both algae, but revealed additive effects for H. opuntia where the combination of both factors reduced dark calcification by 162 % compared to controls. Such species-specific differences in treatment responses indicate H. opuntia is more susceptible to a combination of high DIC and DOC than H. macroloba. From an ecological perspective, results further suggest a reduction of primary production for Halimeda-dominated benthic reef communities under high DOC concentrations and additional decreases of carbonate accretion under elevated DIC concentrations, where H. opuntia dominates the benthic community. This may reduce biogenic carbonate sedimentation rates and hence the buffering capacity against further ocean acidification.

  16. Non-targeted, high resolution mass spectrometry strategy for simultaneous monitoring of xenobiotics and endogenous compounds in green sea turtles on the Great Barrier Reef.

    Science.gov (United States)

    Heffernan, Amy L; Gómez-Ramos, Maria M; Gaus, Caroline; Vijayasarathy, Soumini; Bell, Ian; Hof, Christine; Mueller, Jochen F; Gómez-Ramos, Maria J

    2017-12-01

    Chemical contamination poses a threat to ecosystem, biota and human health, and identifying these hazards is a complex challenge. Traditional hazard identification relies on a priori-defined targets of limited chemical scope, and is generally inappropriate for exploratory studies such as explaining toxicological effects in environmental systems. Here we present a non-target high resolution mass spectrometry environmental monitoring study with multivariate statistical analysis to simultaneously detect biomarkers of exposure (e.g. xenobiotics) and biomarkers of effect in whole turtle blood. Borrowing the concept from clinical chemistry, a case-control sampling approach was used to investigate the potential influence of xenobiotics of anthropogenic origin on free-ranging green sea turtles (Chelonia mydas) from a remote, offshore 'control' site; and two coastal 'case' sites influenced by urban/industrial and agricultural activities, respectively, on the Great Barrier Reef in North Queensland, Australia. Multiple biomarkers of exposure, including sulfonic acids (n=9), a carbamate insecticide metabolite, and other industrial chemicals; and five biomarkers of effect (lipid peroxidation products), were detected in case sites. Additionally, two endogenous biomarkers of neuroinflammation and oxidative stress were identified, and showed moderate-to-strong correlations with clinical measures of inflammation and liver dysfunction. Our data filtering strategy overcomes limitations of traditional a priori selection of target compounds, and adds to the limited environmental xenobiotic metabolomics literature. To our knowledge this is the first case-control study of xenobiotics in marine megafauna, and demonstrates the utility of green sea turtles to link internal and external exposure, to explain potential toxicological effects in environmental systems. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. The role of marine reserves in the replenishment of a locally-impacted population of anemonefish on the Great Barrier Reef

    KAUST Repository

    Bonin, Mary C.; Harrison, Hugo B.; Williamson, David H.; Frisch, Ashley J.; Saenz Agudelo, Pablo; Berumen, Michael L.; Jones, Geoffrey P.

    2015-01-01

    The development of parentage analysis to track the dispersal of juvenile offspring has given us unprecedented insight into the population dynamics of coral reef fishes. These tools now have the potential to inform fisheries management and species conservation, particularly for small fragmented populations under threat from exploitation and disturbance. In this study we resolve patterns of larval dispersal for a population of the anemonefish Amphiprion melanopus in the Keppel Islands (southern Great Barrier Reef). Habitat loss and fishing appear to have impacted this population and a network of no-take marine reserves currently protects 75% of the potential breeders. Using parentage analysis, we estimate that 21% of recruitment in the island group was generated locally, and that breeding adults living in reserves were responsible for 79% (31 out of 39) of these of locally-produced juveniles. Overall, the network of reserves was fully connected via larval dispersal; however one reserve was identified as a critical source of larvae for the island group. The population in the Keppel Islands also appears to be well-connected to other source populations at least 60 km away, given that 79% (145 out of 184) of the juveniles sampled remained unassigned in the parentage analysis. We estimated the effective size of the A. melanopus metapopulation to be 745 (582-993 95% CI) and recommend continued monitoring of its genetic status. Maintaining connectivity with populations beyond the Keppel Islands and recovery of local recruitment habitat, potentially through active restoration of host anemone populations, will be important for its long-term persistence.

  18. The palynology and sedimentology of a coastal swamp at Awana, Great Barrier Island, New Zealand, from c. 7000 yr B.P. to present

    International Nuclear Information System (INIS)

    Horrocks, M.; Ogden, J.; Nichol, S.L.; Alloway, B.V.; Sutton, D.G.

    1999-01-01

    Pollen and sediment analysis of two Holocene cores from Awana, Great Barrier Island, shows that at 7000 calibrated yr B.P. the local swamp was an estuarine salt marsh dominated by Restionaceae. By c. 6000 yr B.P. the water table was lower, and a fresh water swamp (Gleichenia-Leptospermum) had replaced the salt marsh. Regional conifer-hardwood forest c. 7000 yr B.P. was initially co-dominated by Libocedrus and Dacrydium cupressinum. Libocedrus declined from c. 6000 yr B.P. During the period c. 6000-c. 2500 yr B.P., relatively stable environmental conditions ensued with little change in local or regional vegetation. Around 2500 yr B.P., the swamp surface became drier and was invaded by Dacrycarpus and Laurelia swamp forest. This forest was subsequently repeatedly disturbed (not by fire), indicating climatic change to drier and windier conditions. Ascarina lucida was periodically a major component of swamp forest. Disturbance is also recorded in the clastic (mineral) sediments, where beds of sand within finer-grained sediment and peat are interpreted as wind blown material derived from partly devegetated dunes to seaward. The presence of the Kaharoa Tephra allows the timing of major Polynesian deforestation at Awana to be reliably dated to c. 600 calibrated yr B.P. In contrast, we see no evidence in the clastic sediment record of disturbance at Awana since Kaharoa time. We attribute this to the maintenance of stable dunes by a herb/scrub cover despite nearby fires, or to the presence of scrub or forest buffering the swamp from ablating dunes. (author). 45 refs., 4 figs., 1 tab

  19. Spatial variation in pollen and charcoal records in relation to the 665 yr BP Kaharoa tephra at Harataonga Bay, Great Barrier Island, northern New Zealand : preliminary results

    International Nuclear Information System (INIS)

    Horrocks, M.; Nichol, S.L.; Jones, M.D.; Shane, P.A.; Sutton, D.G.

    2001-01-01

    We present preliminary results of a pollen study examining spatial variability using the 665 14 C yr BP Kaharoa tephra as the key stratigraphic marker. Our aim is to highlight potential differences in pollen and charcoal profiles from adjacent sites, and to point out the implications of these differences for the interpretation of pollen records. Three sediment cores were taken from swampy ground behind foredunes at Harataonga Bay, a small catchment on Great Barrier Island. Core 1 provides a c. 5000 14 C yr record of the swamp and is typical of northern New Zealand pollen profiles in that the deforestation signal appears immediately after Kaharoa tephra. Cores 2 and 3, however, show this signal at least 1 m below the tephra layer. Also, artefact pollen of gourd Lagenaria, an introduced Polynesian cultigen, was found 80 cm below the tephra layer in Core 2. This apparent difference in the timing of the human signal may be explained by the occurrence of small-scale, highly localised fires that are not recorded at adjacent sites. This has implications for inferring date of human presence in extensive areas, such as regions or large catchments, from a small number of pollen cores taken from within those areas. An alternative explanation is that sediments in cores 2 and 3 have been reworked to a much greater extent than those in Core 1. This has implications for the use of tephra as critical data for events, particularly when using recent tephra such as Kaharoa for dating human presence when the necessary resolution is to decades or centuries rather than millenia. (author). 18 refs., 6 figs., 2 tabs

  20. The role of marine reserves in the replenishment of a locally-impacted population of anemonefish on the Great Barrier Reef

    KAUST Repository

    Bonin, Mary C.

    2015-11-21

    The development of parentage analysis to track the dispersal of juvenile offspring has given us unprecedented insight into the population dynamics of coral reef fishes. These tools now have the potential to inform fisheries management and species conservation, particularly for small fragmented populations under threat from exploitation and disturbance. In this study we resolve patterns of larval dispersal for a population of the anemonefish Amphiprion melanopus in the Keppel Islands (southern Great Barrier Reef). Habitat loss and fishing appear to have impacted this population and a network of no-take marine reserves currently protects 75% of the potential breeders. Using parentage analysis, we estimate that 21% of recruitment in the island group was generated locally, and that breeding adults living in reserves were responsible for 79% (31 out of 39) of these of locally-produced juveniles. Overall, the network of reserves was fully connected via larval dispersal; however one reserve was identified as a critical source of larvae for the island group. The population in the Keppel Islands also appears to be well-connected to other source populations at least 60 km away, given that 79% (145 out of 184) of the juveniles sampled remained unassigned in the parentage analysis. We estimated the effective size of the A. melanopus metapopulation to be 745 (582-993 95% CI) and recommend continued monitoring of its genetic status. Maintaining connectivity with populations beyond the Keppel Islands and recovery of local recruitment habitat, potentially through active restoration of host anemone populations, will be important for its long-term persistence.

  1. Biology and ecology of the vulnerable holothuroid, Stichopus herrmanni, on a high-latitude coral reef on the Great Barrier Reef

    Science.gov (United States)

    Wolfe, Kennedy; Byrne, Maria

    2017-12-01

    Tropical aspidochirotid holothuroids are among the largest coral reef invertebrates, but gaps remain in our understanding of their ecological roles in lagoon sediment habitats, a vast component of coral-reef ecosystems. Stichopus herrmanni, listed as vulnerable (IUCN), is currently a major fishery species on the Great Barrier Reef (GBR) and throughout the Indo-Pacific. It is critical to characterise how this species interacts with its environment to understand how its removal may impact ecosystem functionality. We investigated seasonal variation in movement, bioturbation, feeding and gonad development of S. herrmanni over 3 yr at One Tree Reef, which has been a no-take area for decades. We determined the direct influence of the deposit-feeding activity of S. herrmanni on sediment turnover and granulometry, and on the abundance of infauna and benthic productivity in a comprehensive in situ analysis of tropical holothuroid feeding ecology. This species is highly mobile with identifiable individuals exhibiting site fidelity over 3 yr. With the potential to turn over an estimated 64-250 kg individual-1 yr-1, S. herrmanni is a major bioturbator. Stichopus herrmanni is a generalist feeder and influences trophic interactions by altering the abundance of infauna and microalgae. Stichopus herrmanni exhibited decreased feeding activity and gonad development in winter, the first documentation of a seasonal disparity in the bioturbation activity of a tropical holothuroid. Sediment digestion and dissolution by S. herrmanni has the potential to influence seawater chemistry, a particularly important feature in a changing ocean. Our results provide essential baseline data on the functional roles of this ecologically important species to inform development of ecosystem-based bêche-de-mer fisheries management on the GBR.

  2. Intra-annual variation in turbidity in response to terrestrial runoff on near-shore coral reefs of the Great Barrier Reef

    Science.gov (United States)

    Fabricius, Katharina E.; De'ath, Glenn; Humphrey, Craig; Zagorskis, Irena; Schaffelke, Britta

    2013-01-01

    Seawater turbidity is a fundamental driver of the ecology of coastal marine systems, and is widely used as indicator for environmental reporting. However, the time scales and processes leading to changes in turbidity in tropical coastal waters remain poorly understood. This study investigates the main determinants of inshore turbidity in four inshore regions along ˜1000 km of the Australian Great Barrier Reef, based on ˜3 years of almost continuous in situ turbidity logger data on 14 reefs. Generalized additive mixed models were used to predict spatial and temporal variation in weekly mean turbidity based on variation in resuspension and runoff conditions. At any given wave height, wave period and tidal range, turbidity was significantly affected by river flow and rainfall. Averaged across all reefs, turbidity was 13% lower (range: 5-37%) in weeks with low compared with high rainfall and river flows. Additionally, turbidity was on average 43% lower 250 days into the dry season than at the start of the dry season on reefs with long-term mean turbidity >1.1 NTU. The data suggest the time scale of winnowing or consolidation of newly imported materials in this zone is months to years. In contrast, turbidity returned to low levels within weeks after river flows and rainfall on reefs with long-term mean turbidity of <1.1 NTU. Turbidity was also up to 10-fold higher on reefs near compared to away from river mouths, suggesting inter-annual accumulation of fine resuspendible sediments. The study suggests that a reduction in the river loads of fine sediments and nutrients through improved land management should lead to measurably improved inshore water clarity in the most turbid parts of the GBR.

  3. Effects of High Dissolved Inorganic and Organic Carbon Availability on the Physiology of the Hard Coral Acropora millepora from the Great Barrier Reef.

    Directory of Open Access Journals (Sweden)

    Friedrich W Meyer

    Full Text Available Coral reefs are facing major global and local threats due to climate change-induced increases in dissolved inorganic carbon (DIC and because of land-derived increases in organic and inorganic nutrients. Recent research revealed that high availability of labile dissolved organic carbon (DOC negatively affects scleractinian corals. Studies on the interplay of these factors, however, are lacking, but urgently needed to understand coral reef functioning under present and near future conditions. This experimental study investigated the individual and combined effects of ambient and high DIC (pCO2 403 μatm/ pHTotal 8.2 and 996 μatm/pHTotal 7.8 and DOC (added as Glucose 0 and 294 μmol L-1, background DOC concentration of 83 μmol L-1 availability on the physiology (net and gross photosynthesis, respiration, dark and light calcification, and growth of the scleractinian coral Acropora millepora (Ehrenberg, 1834 from the Great Barrier Reef over a 16 day interval. High DIC availability did not affect photosynthesis, respiration and light calcification, but significantly reduced dark calcification and growth by 50 and 23%, respectively. High DOC availability reduced net and gross photosynthesis by 51% and 39%, respectively, but did not affect respiration. DOC addition did not influence calcification, but significantly increased growth by 42%. Combination of high DIC and high DOC availability did not affect photosynthesis, light calcification, respiration or growth, but significantly decreased dark calcification when compared to both controls and DIC treatments. On the ecosystem level, high DIC concentrations may lead to reduced accretion and growth of reefs dominated by Acropora that under elevated DOC concentrations will likely exhibit reduced primary production rates, ultimately leading to loss of hard substrate and reef erosion. It is therefore important to consider the potential impacts of elevated DOC and DIC simultaneously to assess real world

  4. Barriers to access to opioid medicines for patients with opioid dependence: a review of legislation and regulations in eleven central and eastern European countries.

    Science.gov (United States)

    Vranken, Marjolein J M; Mantel-Teeuwisse, Aukje K; Jünger, Saskia; Radbruch, Lukas; Scholten, Willem; Lisman, John A; Subataite, Marija; Schutjens, Marie-Hélène D B

    2017-06-01

    Barriers linked to drug control systems are considered to contribute to inequitable access to controlled medicines, leaving millions of people in pain and suffering. Most studies focus on access to opioids for the treatment of severe (cancer) pain. This study aims to identify specific access barriers for patients with opioid dependence in legislation and regulations of 11 central and eastern European countries. This study builds on a previous analysis of legislation and regulations as part of the EU 7th Framework Access To Opioid Medication in Europe (ATOME) project. An in-depth analysis was undertaken to determine specific barriers for patients with opioid dependence in need of opioid analgesics or opioid agonist therapy (OAT). For each country, the number and nature of specific potential barriers for these patients were assessed according to eight categories: prescribing; dispensing; manufacturing; usage; trade and distribution; affordability; penalties; and other. An additional keyword search was conducted to minimize the omission of barriers. Barriers in an additional category, language, were recorded qualitatively. Countries included Bulgaria, Cyprus, Estonia, Greece, Hungary, Latvia, Lithuania, Serbia, Slovakia, Slovenia and Turkey. Ten of the 11 countries (all except Estonia) showed specific potential barriers in their legislation and regulations. The total number of barriers varied from two (Slovenia) to 46 (Lithuania); the number of categories varied from one (Slovenia) to five (Lithuania). Most specific potential barriers were shown in the categories 'prescribing', 'usage' and 'other'. The total number in a single category varied from one to 18 (Lithuania, prescribing). Individual differences between countries in the same specific potential barrier were shown; for example, variation in minimum age criteria for admission to OAT ranging from 15 (Lithuania, in special cases) to 20 years (Greece). All countries had stigmatizing language in their legislation

  5. The late Holocene dry period: multiproxy evidence for an extended drought between 2800 and 1850 cal yr BP across the central Great Basin, USA

    Science.gov (United States)

    Mensing, Scott A.; Sharpe, Saxon E.; Tunno, Irene; Sada, Don W.; Thomas, Jim M.; Starratt, Scott W.; Smith, Jeremy

    2013-01-01

    Evidence of a multi-centennial scale dry period between ∼2800 and 1850 cal yr BP is documented by pollen, mollusks, diatoms, and sediment in spring sediments from Stonehouse Meadow in Spring Valley, eastern central Nevada, U.S. We refer to this period as the Late Holocene Dry Period. Based on sediment recovered, Stonehouse Meadow was either absent or severely restricted in size at ∼8000 cal yr BP. Beginning ∼7500 cal yr BP, the meadow became established and persisted to ∼3000 cal yr BP when it began to dry. Comparison of the timing of this late Holocene drought record to multiple records extending from the eastern Sierra Nevada across the central Great Basin to the Great Salt Lake support the interpretation that this dry period was regional. The beginning and ending dates vary among sites, but all sites record multiple centuries of dry climate between 2500 and 1900 cal yr BP. This duration makes it the longest persistent dry period within the late Holocene. In contrast, sites in the northern Great Basin record either no clear evidence of drought, or have wetter than average climate during this period, suggesting that the northern boundary between wet and dry climates may have been between about 40° and 42° N latitude. This dry in the southwest and wet in the northwest precipitation pattern across the Great Basin is supported by large-scale spatial climate pattern hypotheses involving ENSO, PDO, AMO, and the position of the Aleutian Low and North Pacific High, particularly during winter.

  6. Great earthquake potential in Oregon and Washington: An overview of recent coastal geologic studies and possible segmentation of the central Cascadia subduction zone

    International Nuclear Information System (INIS)

    Nelson, A.R.; Personius, S.F.

    1990-01-01

    Fundamental questions in earthquake hazards research in the Pacific Northwest concern the magnitude and recurrence of great earthquakes in the Cascadia subduction zone in Oregon and Washington. Geologic work of the last few years has produced convincing evidence for coseismic subsidence along the Washington and Oregon coasts. Regional subsidence recorded by estuarine deposits suggests that plate-interface earthquakes of at least M w 8 (>100-km-long ruptures) occurred during the late Holocene in northern Oregon and southern Washington. Differences in the types of coastal marsh sequences between northern and south-central Oregon, however, suggest that regional coastal subsidence does not extend south of about 45.5 degrees N along the Oregon coast. North of this latitude, the coast may intersect the seaward edge of a zone of coseismic subsidence that continues southward onshore. Alternatively, the Cascadia subduction zone is segmented near 44-45 degrees N; a segment boundary at this location would suggest that plate-interface events near M w 8 along the central CSZ would be more frequent than larger (M w 9) events. South of this boundary in the Coos Bay region, the tectonic framework developed through mapping and dating of marine and fluvial terraces indicates that many episodes of abrupt marsh burial in south-central Oregon are best interpreted as the product of deformation on local structures. Some of the local deformation could be associated with moderate earthquakes (M s <6). At most sites in south-central Oregon, however, it is still unclear whether coseismic events were responses to local faulting or folding, to regional deformation during great plate-interface earthquakes, or to both. This study has potential implications for risk assessments for light water reactors in North America

  7. Development of a high spectral resolution surface albedo product for the ARM Southern Great Plains Central Facility

    Energy Technology Data Exchange (ETDEWEB)

    McFarlane, Sally A.; Gaustad, Krista L.; Mlawer, Eli J.; Long, Charles N.; Delamere, Jennifer

    2011-09-01

    We present a method for identifying dominant surface type and estimating high spectral resolution surface albedo at the Atmospheric Radiation Measurement (ARM) facility at the Southern Great Plains (SGP) site in Oklahoma for use in radiative transfer calculations. Given a set of 6-channel narrowband visible and near-infrared irradiance measurements from upward and downward looking multi-filter radiometers (MFRs), four different surface types (snow-covered, green vegetation, partial vegetation, non-vegetated) can be identified. A normalized difference vegetation index (NDVI) is used to distinguish between vegetated and non-vegetated surfaces, and a scaled NDVI index is used to estimate the percentage of green vegetation in partially vegetated surfaces. Based on libraries of spectral albedo measurements, a piecewise continuous function is developed to estimate the high spectral resolution surface albedo for each surface type given the MFR albedo values as input. For partially vegetated surfaces, the albedo is estimated as a linear combination of the green vegetation and non-vegetated surface albedo values. The estimated albedo values are evaluated through comparison to high spectral resolution albedo measurements taken during several Intensive Observational Periods (IOPs) and through comparison of the integrated spectral albedo values to observed broadband albedo measurements. The estimated spectral albedo values agree well with observations for the visible wavelengths constrained by the MFR measurements, but have larger biases and variability at longer wavelengths. Additional MFR channels at 1100 nm and/or 1600 nm would help constrain the high resolution spectral albedo in the near infrared region.

  8. Development of a high spectral resolution surface albedo product for the ARM Southern Great Plains central facility

    Science.gov (United States)

    McFarlane, S. A.; Gaustad, K. L.; Mlawer, E. J.; Long, C. N.; Delamere, J.

    2011-09-01

    We present a method for identifying dominant surface type and estimating high spectral resolution surface albedo at the Atmospheric Radiation Measurement (ARM) facility at the Southern Great Plains (SGP) site in Oklahoma for use in radiative transfer calculations. Given a set of 6-channel narrowband visible and near-infrared irradiance measurements from upward and downward looking multi-filter radiometers (MFRs), four different surface types (snow-covered, green vegetation, partial vegetation, non-vegetated) can be identified. A normalized difference vegetation index (NDVI) is used to distinguish between vegetated and non-vegetated surfaces, and a scaled NDVI index is used to estimate the percentage of green vegetation in partially vegetated surfaces. Based on libraries of spectral albedo measurements, a piecewise continuous function is developed to estimate the high spectral resolution surface albedo for each surface type given the MFR albedo values as input. For partially vegetated surfaces, the albedo is estimated as a linear combination of the green vegetation and non-vegetated surface albedo values. The estimated albedo values are evaluated through comparison to high spectral resolution albedo measurements taken during several Intensive Observational Periods (IOPs) and through comparison of the integrated spectral albedo values to observed broadband albedo measurements. The estimated spectral albedo values agree well with observations for the visible wavelengths constrained by the MFR measurements, but have larger biases and variability at longer wavelengths. Additional MFR channels at 1100 nm and/or 1600 nm would help constrain the high resolution spectral albedo in the near infrared region.

  9. Development of a high spectral resolution surface albedo product for the ARM Southern Great Plains central facility

    Directory of Open Access Journals (Sweden)

    J. Delamere

    2011-09-01

    Full Text Available We present a method for identifying dominant surface type and estimating high spectral resolution surface albedo at the Atmospheric Radiation Measurement (ARM facility at the Southern Great Plains (SGP site in Oklahoma for use in radiative transfer calculations. Given a set of 6-channel narrowband visible and near-infrared irradiance measurements from upward and downward looking multi-filter radiometers (MFRs, four different surface types (snow-covered, green vegetation, partial vegetation, non-vegetated can be identified. A normalized difference vegetation index (NDVI is used to distinguish between vegetated and non-vegetated surfaces, and a scaled NDVI index is used to estimate the percentage of green vegetation in partially vegetated surfaces. Based on libraries of spectral albedo measurements, a piecewise continuous function is developed to estimate the high spectral resolution surface albedo for each surface type given the MFR albedo values as input. For partially vegetated surfaces, the albedo is estimated as a linear combination of the green vegetation and non-vegetated surface albedo values. The estimated albedo values are evaluated through comparison to high spectral resolution albedo measurements taken during several Intensive Observational Periods (IOPs and through comparison of the integrated spectral albedo values to observed broadband albedo measurements. The estimated spectral albedo values agree well with observations for the visible wavelengths constrained by the MFR measurements, but have larger biases and variability at longer wavelengths. Additional MFR channels at 1100 nm and/or 1600 nm would help constrain the high resolution spectral albedo in the near infrared region.

  10. A modern Sr/Ca-δ18O-sea surface temperature calibration for Isopora corals on the Great Barrier Reef

    Science.gov (United States)

    Brenner, Logan D.; Linsley, Braddock K.; Potts, Donald C.

    2017-02-01

    Isopora (Acroporidae) is a genus of often encrusting, branching to submassive corals that are common in many shallow habitats on modern and fossil Indo-West Pacific reefs. Although abundant, Isopora is largely absent from paleoceanographic literature. The scarcity of large Porites and the abundance of Isopora retrieved from the Great Barrier Reef (GBR) on Integrated Ocean Drilling Program Expedition 325 focused paleoceanographic attention on Isopora. Here we provide the first independent high-resolution calibration of both Sr/Ca and δ18O for temperature analyses based on Isopora and demonstrate its consistency with Porites records. We developed modern skeletal Sr/Ca- and δ18O-sea surface temperature (SST) calibrations based on five modern Isopora colonies from Heron Island in the southern GBR. Pairing the coral Sr/Ca record with monthly SST data yielded Sr/Ca-SST sensitivities from -0.061 ± 0.004 (centered) to -0.083 ± 0.007 (raw) mmol/mol °C-1 based on reduced major axis regressions. These sensitivities are in the middle of the range of published Porites values and overlap most published values for Isopora, -0.075 ± 0.011 to -0.065 ± 0.011 mmol/mol °C-1. The δ18O-SST sensitivities range from -0.184 ± 0.014 (centered) to -0.185 ± 0.014 (raw) ‰ °C-1, assuming that all seasonal variation in δ18O was due to SST. These δ18O-SST sensitivities are smaller than the widely accepted value of -0.23‰ °C-1 for biogenic aragonite but are at the upper end of high-resolution Porites-defined sensitivities that are consistently less than the aforementioned established value. Our results validate the use of Isopora as an alternative source of paleoceanographic records in habitats where large massive Porites are scarce or absent.

  11. A Modern Sr/Ca-δ18O-Sea Surface Temperature Calibration for Isopora Corals in the Great Barrier Reef

    Science.gov (United States)

    Brenner, L. D.; Linsley, B. K.; Potts, D. C.

    2014-12-01

    Most coral-based paleoceanographic studies have used massive colonies of Porites or Faviidae, due to their long, continuously accreted skeletal records and sub-annual resolution, but other sub-massive corals provide an untapped resource. The genus Isopora is a dominant reef builder in some high-energy environments in the tropical western Pacific, and was a major component of cores recovered on IODP Leg 325 off the Great Barrier Reef (GBR). Despite its abundance, Isopora remains largely unexplored and hence underutilized in paleoceanographic studies. We present a modern Sr/Ca-δ18O-Sea Surface Temperature (SST) calibration of modern Isopora corals (n=3) collected from inner and outer reef locations ranging from 1-13m depth by Heron Island in the southern GBR in 2012. Pairing the Isopora Sr/Ca record with monthly SST yielded an average relationship of SST=-11.48×(Sr/Ca)+131.1 (r2 = 0.42-0.78). The Sr/Ca sensitivity of -0.087 mmol/mol/°C is similar to the sensitivity for Porites that was corrected for tissue layer smoothing effects determined by Gagan et al. (2012). The similarity between our Sr/Ca-SST sensitivity and the corrected sensitivity for Porites suggests tissue layer effects are minimal in Isopora. The mean annual SST amplitude recorded by the corals from 2008-2011 (full annual cycles) was 5.3°C and the average δ18O annual cycle of 1.1‰ approximates that expected if salinity had little effect on coral δ18O, assuming a previously established conversion of -0.23‰ (δ18O)/°C for biogenic aragonite. The average annual salinity amplitude of 0.3 in gridded data from around Heron Island supports our conclusion that δ18O variability is forced almost completely by SST. This modern Sr/Ca-SST calibration will expand the paleoceanographic utility of Isopora and, by assisting interpretation of Sr/Ca data from fossil corals collected during IODP 325, will better constrain the timing and magnitude of sea level changes and surface conditions since the Last

  12. Coral reefs of the turbid inner-shelf of the Great Barrier Reef, Australia: An environmental and geomorphic perspective on their occurrence, composition and growth

    Science.gov (United States)

    Browne, N. K.; Smithers, S. G.; Perry, C. T.

    2012-10-01

    Investigations of the geomorphic and sedimentary context in which turbid zone reefs exist, both in the modern and fossil reef record, can inform key ecological debates regarding species tolerances and adaptability to elevated turbidity and sedimentation. Furthermore, these investigations can address critical geological and palaeoecological questions surrounding longer-term coral-sediment interactions and reef growth histories. Here we review current knowledge about turbid zone reefs from the inner-shelf regions of the Great Barrier Reef (GBR) in Australia to consider these issues and to evaluate reef growth in the period prior to and post European settlement. We also consider the future prospects of these reefs under reported changing water quality regimes. Turbid zone reefs on the GBR are relatively well known compared to those in other reef regions. They occur within 20 km of the mainland coast where reef development may be influenced by continual or episodic terrigenous sediment inputs, fluctuating salinities (24-36 ppt), and reduced water quality through increased nutrient and pollutant delivery from urban and agricultural runoff. Individually, and in synergy, these environmental conditions are widely viewed as unfavourable for sustained and vigorous coral reef growth, and thus these reefs are widely perceived as marginal compared to clear water reef systems. However, recent research has revealed that this view is misleading, and that in fact many turbid zone reefs in this region are resilient, exhibit relatively high live coral cover (> 30%) and have distinctive community assemblages dominated by fast growing (Acropora, Montipora) and/or sediment tolerant species (Turbinaria, Goniopora, Galaxea, Porites). Palaeoecological reconstructions based on the analysis of reef cores show that community assemblages are relatively stable at millennial timescales, and that many reefs are actively accreting (average 2-7 mm/year) where accommodation space is available

  13. A population genetic assessment of coral recovery on highly disturbed reefs of the Keppel Island archipelago in the southern Great Barrier Reef

    Directory of Open Access Journals (Sweden)

    Madeleine J.H. van Oppen

    2015-07-01

    Full Text Available Coral reefs surrounding the islands lying close to the coast are unique to the Great Barrier Reef (GBR in that they are frequently exposed to disturbance events including floods caused by cyclonic rainfall, strong winds and occasional periods of prolonged above-average temperatures during summer. In one such group of islands in the southern GBR, the Keppel Island archipelago, climate-driven disturbances frequently result in major coral mortality. Whilst these island reefs have clearly survived such dramatic disturbances in the past, the consequences of extreme mortality events may include the loss of genetic diversity, and hence adaptive potential, and a reduction in fitness due to inbreeding, especially if new recruitment from external sources is limited. Here we examined the level of isolation of the Keppel Island group as well as patterns of gene flow within the Keppel Islands using 10 microsatellite markers in nine populations of the coral, Acropora millepora. Bayesian cluster analysis and assignment tests indicated gene flow is restricted, but not absent, between the outer and inner Keppel Island groups, and that extensive gene flow exists within each of these island groups. Comparison of the Keppel Island data with results from a previous GBR-wide study that included a single Keppel Island population, confirmed that A. millepora in the Keppel Islands is genetically distinct from populations elsewhere on the GBR, with exception of the nearby inshore High Peak Reef just north of the Keppel Islands. We compared patterns of genetic diversity in the Keppel Island populations with those from other GBR populations and found them to be slightly, but significantly lower, consistent with the archipelago being geographically isolated, but there was no evidence for recent bottlenecks or deviation from mutation-drift equilibrium. A high incidence of private alleles in the Keppel Islands, particularly in the outer islands, supports their relative

  14. Blood-brain barrier-on-a-chip: Microphysiological systems that capture the complexity of the blood-central nervous system interface.

    Science.gov (United States)

    Phan, Duc Tt; Bender, R Hugh F; Andrejecsk, Jillian W; Sobrino, Agua; Hachey, Stephanie J; George, Steven C; Hughes, Christopher Cw

    2017-11-01

    The blood-brain barrier is a dynamic and highly organized structure that strictly regulates the molecules allowed to cross the brain vasculature into the central nervous system. The blood-brain barrier pathology has been associated with a number of central nervous system diseases, including vascular malformations, stroke/vascular dementia, Alzheimer's disease, multiple sclerosis, and various neurological tumors including glioblastoma multiforme. There is a compelling need for representative models of this critical interface. Current research relies heavily on animal models (mostly mice) or on two-dimensional (2D) in vitro models, neither of which fully capture the complexities of the human blood-brain barrier. Physiological differences between humans and mice make translation to the clinic problematic, while monolayer cultures cannot capture the inherently three-dimensional (3D) nature of the blood-brain barrier, which includes close association of the abluminal side of the endothelium with astrocyte foot-processes and pericytes. Here we discuss the central nervous system diseases associated with blood-brain barrier pathology, recent advances in the development of novel 3D blood-brain barrier -on-a-chip systems that better mimic the physiological complexity and structure of human blood-brain barrier, and provide an outlook on how these blood-brain barrier-on-a-chip systems can be used for central nervous system disease modeling. Impact statement The field of microphysiological systems is rapidly evolving as new technologies are introduced and our understanding of organ physiology develops. In this review, we focus on Blood-Brain Barrier (BBB) models, with a particular emphasis on how they relate to neurological disorders such as Alzheimer's disease, multiple sclerosis, stroke, cancer, and vascular malformations. We emphasize the importance of capturing the three-dimensional nature of the brain and the unique architecture of the BBB - something that until recently

  15. Land-use effects on fluxes of suspended sediment, nitrogen and phosphorus from a river catchment of the Great Barrier Reef, Australia

    Science.gov (United States)

    Hunter, Heather M.; Walton, Richard S.

    2008-07-01

    SummaryA 6-year study was conducted in the Johnstone River system in the wet tropics of north-eastern Australia, to address concerns that the Great Barrier Reef is at risk from elevated levels of suspended sediment (SS) and nutrients discharged from its river catchments. Aims were to quantify: (i) fluxes of SS, phosphorus (P) and nitrogen (N) exported annually from the catchment and (ii) the influence of rural land uses on these fluxes. Around 55% of the 1602 km2 catchment was native rainforest, with the reminder developed mainly for livestock and crop production. Water quality and stream flow were monitored at 16 sites, with the emphasis on sampling major runoff events. Monitoring data were used to calibrate a water quality model for the catchment (HSPF), which was run with 39 years of historical precipitation and evaporation data. Modelled specific fluxes from the catchment of 1.2 ± 1.1 t SS ha-1 y-1, 2.2 ± 1.8 kg P ha-1 y-1 and 11.4 ± 7.3 kg N ha-1y-1 were highly variable between and within years. Fluxes of SS and P were strongly dominated by major events, with 91% of SS and 84% of P exported during the highest 10% of daily flows. On average, sediment P comprised 81% of the total P flux. The N flux was less strongly dominated by major events and sediment N comprised 46% of total N exports. Specific fluxes of SS, N and P from areas receiving precipitation of 3545 mm y-1 were around 3-4 times those from areas receiving 1673 mm y-1. For a given mean annual precipitation, specific fluxes of SS and P from beef pastures, dairy pastures and unsewered residential areas were similar to those from rainforest, while fluxes from areas of sugar cane and bananas were 3-4 times higher. Specific fluxes of N from areas with an annual precipitation of 3545 mm ranged from 8.9 ± 6.5 kg N ha-1 y-1 (rainforest) to 72 ± 50 kg N ha-1 y-1 (unsewered residential). Aggregated across the entire catchment, disproportionately large fluxes of SS, total P and total N were derived from

  16. Sequential development of platform to off-platform facies of the great American carbonate bank in the central Appalachians: chapter 15

    Science.gov (United States)

    Brezinski, David K.; Taylor, John F.; Repetski, John E.

    2012-01-01

    In the central Appalachians, carbonate deposition of the great American carbonate bank began during the Early Cambrian with the creation of initial ramp facies of the Vintage Formation and lower members of the Tomstown Formation. Vertical stacking of bioturbated subtidal ramp deposits (Bolivar Heights Member) and dolomitized microbial boundtsone (Fort Duncan Member) preceded the initiation of platform sedimentation and creation of sand shoal facies (Benevola Member) that was followed by the development of peritidal cyclicity (Daragan Member). Initiation of peritidal deposition coincided with the development of a rimmed platform that would persist throughout much of the Cambrian and Early Odrovician. At the end of deposition of the Waynesboro Formation, the platform became subaerially exposed because of the Hawke Bay regression, bringing the Sauk I supersequence to and end. In the Conestoga Valley of eastern Pennsylvania, Early Cambrian ramp deposition was succeeded by deposition of platform-margin and periplatfrom facies of the Kinzers Formation.

  17. Instrumenting the Conifers: A Look at Daily Tree Growth and Locally Observed Environmental Conditions Across Four Mountain Sites in the Central Great Basin, USA

    Science.gov (United States)

    Strachan, S.; Biondi, F.; Johnson, B. G.

    2012-12-01

    Tree growth is often used as a proxy for past environmental conditions or as an indicator of developing trends. Reconstructions of drought, precipitation, temperature, and other phenomena derived from tree-growth indices abound in scientific literature aimed at informing policy makers. Observations of tree recruitment or death in treeline populations are frequently tied to climatic fluctuation in cause-effect hypotheses. Very often these hypotheses are based on statistical relationships between annual-to-seasonal tree growth measurements and some environmental parameter measured or modeled off-site. Observation of daily tree growth in conjunction with in-situ environmental measurements at similar timescales takes us one step closer to quantifying the uncertainty in reconstruction or predictive studies. In four separate sites in two different mountain ranges in the central Great Basin, co-located observations of conifer growth activity and local atmospheric and soils conditions have been initiated. Species include Pinus longaeva (Great Basin bristlecone pine), Pinus flexilis (limber pine), Picea engelmannii (Engelmann spruce), Pinus monophylla (singleleaf pinyon pine), Pinus ponderosa (ponderosa pine), Abies concolor (white fir), and Pseudotsuga menziesii (Douglas-fir). Measurements of sub-hourly tree radial length change and sap flow activity are compared with a suite of in-situ observations including air temperature, precipitation, photosynthetically-active radiation (PAR), relative humidity, soil temperature, and soil moisture/water content. Subalpine study site located at 3360 m elevation in the Snake Range, Nevada

  18. Larval trematodes (Digenea of the great pond snail, Lymnaea stagnalis (L., (Gastropoda, Pulmonata in Central Europe: a survey of species and key to their identification

    Directory of Open Access Journals (Sweden)

    Faltýnková A.

    2007-03-01

    Full Text Available A survey of cercariae and metacercariae (Trematoda, Digenea from the great pond snail (Lymnaea stagnalis in Central Europe (Austria, Czech Republic, South-East Germany, Poland and Slovak Republic is presented, based on a study of 3,628 snails examined from 1998 to 2005. A total of 953 (26.3% L. stagnalis were infected with 24 trematode species comprising 19 species of cercariae and 11 species of metacercariae (six species occurred both as cercarie and metacercarie of eight families. The dominant cercariae were those of Opisthioglyphe ranae (159 hosts infected, Plagiorchis elegans (141 (both family Plagiorchiidae and Echinoparyphium aconiatum (153 (Echinostomatidae; 14 double infections were found. The most frequent metacercariae were those of Neoglyphe locellus (71 (Omphalometridae, E. aconiatum (66, Echinostoma sp. (59 and Moliniella anceps (48 (Echinostomatidae. In the previous studies carried out in Central Europe, a very similar spectrum of nine trematode families of 22 cercariae determined to species level and 43 types of cercariae reported under generic or provisional names, which can be in many cases conspecific with the previous taxa, were found. A simple key to identification of cercariae and metacercariae, together with their illustrations, is provided.

  19. STRUCTURAL AND HIDDEN BARRIERS TO A LOCAL PRIMARY HEALTH CARE INFRASTRUCTURE: AUTONOMY, DECISIONS ABOUT PRIMARY HEALTH CARE, AND THE CENTRALITY AND SIGNIFICANCE OF POWER.

    Science.gov (United States)

    Freed, Christopher R; Hansberry, Shantisha T; Arrieta, Martha I

    2013-09-01

    To examine a local primary health care infrastructure and the reality of primary health care from the perspective of residents of a small, urban community in the southern United States. Data derive from 13 semi-structured focus groups, plus three semi-structured interviews, and were analyzed inductively consistent with a grounded theory approach. Structural barriers to the local primary health care infrastructure include transportation, clinic and appointment wait time, and co-payments and health insurance. Hidden barriers consist of knowledge about local health care services, non-physician gatekeepers, and fear of medical care. Community residents have used home remedies and the emergency department at the local academic medical center to manage these structural and hidden barriers. Findings might not generalize to primary health care infrastructures in other communities, respondent perspectives can be biased, and the data are subject to various interpretations and conceptual and thematic frameworks. Nevertheless, the structural and hidden barriers to the local primary health care infrastructure have considerably diminished the autonomy community residents have been able to exercise over their decisions about primary health care, ultimately suggesting that efforts concerned with increasing the access of medically underserved groups to primary health care in local communities should recognize the centrality and significance of power. This study addresses a gap in the sociological literature regarding the impact of specific barriers to primary health care among medically underserved groups.

  20. Viral Infection of the Central Nervous System and Neuroinflammation Precede Blood-Brain Barrier Disruption during Japanese Encephalitis Virus Infection.

    Science.gov (United States)

    Li, Fang; Wang, Yueyun; Yu, Lan; Cao, Shengbo; Wang, Ke; Yuan, Jiaolong; Wang, Chong; Wang, Kunlun; Cui, Min; Fu, Zhen F

    2015-05-01

    Japanese encephalitis is an acute zoonotic, mosquito-borne disease caused by Japanese encephalitis virus (JEV). Japanese encephalitis is characterized by extensive inflammation in the central nervous system (CNS) and disruption of the blood-brain barrier (BBB). However, the pathogenic mechanisms contributing to the BBB disruption are not known. Here, using a mouse model of intravenous JEV infection, we show that virus titers increased exponentially in the brain from 2 to 5 days postinfection. This was accompanied by an early, dramatic increase in the level of inflammatory cytokines and chemokines in the brain. Enhancement of BBB permeability, however, was not observed until day 4, suggesting that viral entry and the onset of inflammation in the CNS occurred prior to BBB damage. In vitro studies revealed that direct infection with JEV could not induce changes in the permeability of brain microvascular endothelial cell monolayers. However, brain extracts derived from symptomatic JEV-infected mice, but not from mock-infected mice, induced significant permeability of the endothelial monolayer. Consistent with a role for inflammatory mediators in BBB disruption, the administration of gamma interferon-neutralizing antibody ameliorated the enhancement of BBB permeability in JEV-infected mice. Taken together, our data suggest that JEV enters the CNS, propagates in neurons, and induces the production of inflammatory cytokines and chemokines, which result in the disruption of the BBB. Japanese encephalitis (JE) is the leading cause of viral encephalitis in Asia, resulting in 70,000 cases each year, in which approximately 20 to 30% of cases are fatal, and a high proportion of patients survive with serious neurological and psychiatric sequelae. Pathologically, JEV infection causes an acute encephalopathy accompanied by BBB dysfunction; however, the mechanism is not clear. Thus, understanding the mechanisms of BBB disruption in JEV infection is important. Our data demonstrate

  1. Antiseptic barrier cap effective in reducing central line-associated bloodstream infections : A systematic review and meta-analysis

    NARCIS (Netherlands)

    Voor In 't Holt, Anne F; Helder, Onno K; Vos, Margreet C; Schafthuizen, Laura; Sülz, Sandra; van den Hoogen, Agnes; Ista, Erwin

    2017-01-01

    BACKGROUND: Microorganisms can intraluminally access a central venous catheter via the catheter hub. The catheter hub should be appropriately disinfected to prevent central line-associated bloodstream infections (CLABSIs). However, compliance with the time-consuming manual disinfection process is

  2. Project plan-Surficial geologic mapping and hydrogeologic framework studies in the Greater Platte River Basins (Central Great Plains) in support of ecosystem and climate change research

    Science.gov (United States)

    Berry, Margaret E.; Lundstrom, Scott C.; Slate, Janet L.; Muhs, Daniel R.; Sawyer, David A.; VanSistine, D. Paco

    2011-01-01

    The Greater Platte River Basin area spans a central part of the Midcontinent and Great Plains from the Rocky Mountains on the west to the Missouri River on the east, and is defined to include drainage areas of the Platte, Niobrara, and Republican Rivers, the Rainwater Basin, and other adjoining areas overlying the northern High Plains aquifer. The Greater Platte River Basin contains abundant surficial deposits that were sensitive to, or are reflective of, the climate under which they formed: deposits from multiple glaciations in the mountain headwaters of the North and South Platte Rivers and from continental ice sheets in eastern Nebraska; fluvial terraces (ranging from Tertiary to Holocene in age) along the rivers and streams; vast areas of eolian sand in the Nebraska Sand Hills and other dune fields (recording multiple episodes of dune activity); thick sequences of windblown silt (loess); and sediment deposited in numerous lakes and wetlands. In addition, the Greater Platte River Basin overlies and contributes surface water to the High Plains aquifer, a nationally important groundwater system that underlies parts of eight states and sustains one of the major agricultural areas of the United States. The area also provides critical nesting habitat for birds such as plovers and terns, and roosting habitat for cranes and other migratory birds that travel through the Central Flyway of North America. This broad area, containing fragile ecosystems that could be further threatened by changes in climate and land use, has been identified by the USGS and the University of Nebraska-Lincoln as a region where intensive collaborative research could lead to a better understanding of climate change and what might be done to adapt to or mitigate its adverse effects to ecosystems and to humans. The need for robust data on the geologic framework of ecosystems in the Greater Platte River Basin has been acknowledged in proceedings from the 2008 Climate Change Workshop and in draft

  3. Mollusk communities of the central Congo River shaped by combined effects of barriers, environmental gradients, and species dispersal

    Directory of Open Access Journals (Sweden)

    Oscar Wembo Ndeo

    2017-05-01

    Full Text Available Rapids, falls, and cascades might act as barriers for freshwater species, determining the species community up- and downstream of barriers. However, they affect community composition not only by acting as barriers but also by their influence on environmental gradients. Moreover, the directional dispersal of species along the watercourse might determine community composition. A suitable system to study these differential effects is the Congo River, the world’s second largest river by discharge. The small ‘Upper Congo Rapids’ ecoregion features several rapids known as barrier for fishes. The Wagenia Cataracts at the town of Kisangani constitute the strongest drop of the Congo River and several studies have emphasized its role as barrier for fish distribution. Alternative explanations for this pattern, however, are rarely evaluated. Though mollusks represent a vital component of the macrozoobenthos, with distribution patterns and underlying drivers often distinct from that of fishes, virtually no field surveys of the Congo River have been reported for decades. We collected and determined mollusks of 51 stations, recorded environmental conditions, and generated proxies for directional species dispersal and an indirect barrier effect. Those variables were subjected to distance-based redundancy analyses and variation partitioning in order to test whether the mollusk community compositions are better explained by an individual or combined influence of the direct and indirect effect of the cataract barrier, environmental conditions, and downstream-directed dispersal. Our survey showed an exclusive upstream/downstream distribution for just four out of the 19 species, suggesting a limited barrier effect. We revealed no direct influence of the barrier itself on community composition but of substrate type. However, we found an indirect effect of the barrier through replacing spatially structured communities upstream of the cataract with more uniform

  4. Ground-Water Flow Direction, Water Quality, Recharge Sources, and Age, Great Sand Dunes National Monument, South-Central Colorado, 2000-2001

    Science.gov (United States)

    Rupert, Michael G.; Plummer, Niel

    2004-01-01

    Great Sand Dunes National Monument is located in south-central Colorado along the eastern edge of the San Luis Valley. The Great Sand Dunes National Monument contains the tallest sand dunes in North America; some rise up to750 feet. Important ecological features of the Great Sand Dunes National Monument are palustrine wetlands associated with interdunal ponds and depressions along the western edge of the dune field. The existence and natural maintenance of the dune field and the interdunal ponds are dependent on maintaining ground-water levels at historic elevations. To address these concerns, the U.S. Geological Survey conducted a study, in collaboration with the National Park Service, of ground-water flow direction, water quality, recharge sources, and age at the Great Sand Dunes National Monument. A shallow unconfined aquifer and a deeper confined aquifer are the two principal aquifers at the Great Sand Dunes National Monument. Ground water in the unconfined aquifer is recharged from Medano and Sand Creeks near the Sangre de Cristo Mountain front, flows underneath the main dune field, and discharges to Big and Little Spring Creeks. The percentage of calcium in ground water in the unconfined aquifer decreases and the percentage of sodium increases because of ionic exchange with clay minerals as the ground water flows underneath the dune field. It takes more than 60 years for the ground water to flow from Medano and Sand Creeks to Big and Little Spring Creeks. During this time, ground water in the upper part of the unconfined aquifer is recharged by numerous precipitation events. Evaporation of precipitation during recharge prior to reaching the water table causes enrichment in deuterium (2H) and oxygen-18 (18O) relative to waters that are not evaporated. This recharge from precipitation events causes the apparent ages determined using chlorofluorocarbons and tritium to become younger, because relatively young precipitation water is mixing with older waters

  5. Land-Sparing Opportunities for Solar Energy Development in Agricultural Landscapes: A Case Study of the Great Central Valley, CA, United States.

    Science.gov (United States)

    Hoffacker, Madison K; Allen, Michael F; Hernandez, Rebecca R

    2017-12-19

    Land-cover change from energy development, including solar energy, presents trade-offs for land used for the production of food and the conservation of ecosystems. Solar energy plays a critical role in contributing to the alternative energy mix to mitigate climate change and meet policy milestones; however, the extent that solar energy development on nonconventional surfaces can mitigate land scarcity is understudied. Here, we evaluate the land sparing potential of solar energy development across four nonconventional land-cover types: the built environment, salt-affected land, contaminated land, and water reservoirs (as floatovoltaics), within the Great Central Valley (CV, CA), a globally significant agricultural region where land for food production, urban development, and conservation collide. Furthermore, we calculate the technical potential (TWh year -1 ) of these land sparing sites and test the degree to which projected electricity needs for the state of California can be met therein. In total, the CV encompasses 15% of CA, 8415 km 2 of which was identified as potentially land-sparing for solar energy development. These areas comprise a capacity-based energy potential of at least 17 348 TWh year -1 for photovoltaic (PV) and 2213 TWh year -1 for concentrating solar power (CSP). Accounting for technology efficiencies, this exceeds California's 2025 projected electricity demands up to 13 and 2 times for PV and CSP, respectively. Our study underscores the potential of strategic renewable energy siting to mitigate environmental trade-offs typically coupled with energy sprawl in agricultural landscapes.

  6. Knowledge, Attitude, and Perception of Barriers for Eye Care among Diabetic Persons Registered at Employee Health Department of a Tertiary Eye Hospital of Central Saudi Arabia

    Science.gov (United States)

    Al-Alawi, Abeer; Al-Hassan, Arif; Chauhan, Deepti; Al-Futais, Muneera; Khandekar, Rajiv

    2016-01-01

    Purpose: To evaluate the level of knowledge, attitudes, and barriers to diabetic retinopathy (DR) screening among diabetic healthcare staff at a tertiary eye hospital in central Saudi Arabia. Methods: This was a descriptive survey using a closed-ended questionnaire. A. 5-grade. Likert scale was used for responses to each question. Data were collected on patient demographics and the status of diabetes. Survey responses related to knowledge, attitude, and barriers were grouped. Results: The study sample was comprised of 45 diabetics employed at the hospital. The mean age was 49 ± 11 years and 33 diabetics were males. One-third of the study population was referred to the eye clinic for DR screening. DR screening was performed in 25% of diabetics over the previous year. Twenty-nine (64%; 95% confidence intervals: 50–78) participants had excellent knowledge of eyecare for diabetic complications. Thirteen percent of participants had a positive attitude toward periodic eye checkups. Travel distance to an eyecare unit, no referral from family physicians for annual eye checkups and the lack of availability of gender-specific eyecare professionals were the main perceived barriers. Conclusion: Annual DR screening needs to be promoted to primary healthcare providers and diabetic patients. Barriers should be addressed to improve the uptake of DR screening. PMID:26957842

  7. Knowledge, Attitude, and Perception of Barriers for Eye Care among Diabetic Persons Registered at Employee Health Department of a Tertiary Eye Hospital of Central Saudi Arabia.

    Science.gov (United States)

    Al-Alawi, Abeer; Al-Hassan, Arif; Chauhan, Deepti; Al-Futais, Muneera; Khandekar, Rajiv

    2016-01-01

    To evaluate the level of knowledge, attitudes, and barriers to diabetic retinopathy (DR) screening among diabetic healthcare staff at a tertiary eye hospital in central Saudi Arabia. This was a descriptive survey using a closed-ended questionnaire. A. 5-grade. Likert scale was used for responses to each question. Data were collected on patient demographics and the status of diabetes. Survey responses related to knowledge, attitude, and barriers were grouped. The study sample was comprised of 45 diabetics employed at the hospital. The mean age was 49 ± 11 years and 33 diabetics were males. One-third of the study population was referred to the eye clinic for DR screening. DR screening was performed in 25% of diabetics over the previous year. Twenty-nine (64%; 95% confidence intervals: 50-78) participants had excellent knowledge of eyecare for diabetic complications. Thirteen percent of participants had a positive attitude toward periodic eye checkups. Travel distance to an eyecare unit, no referral from family physicians for annual eye checkups and the lack of availability of gender-specific eyecare professionals were the main perceived barriers. Annual DR screening needs to be promoted to primary healthcare providers and diabetic patients. Barriers should be addressed to improve the uptake of DR screening.

  8. Impact of removing mucosal barrier injury laboratory-confirmed bloodstream infections from central line-associated bloodstream infection rates in the National Healthcare Safety Network, 2014.

    Science.gov (United States)

    See, Isaac; Soe, Minn M; Epstein, Lauren; Edwards, Jonathan R; Magill, Shelley S; Thompson, Nicola D

    2017-03-01

    Central line-associated bloodstream infection (CLABSI) event data reported to the National Healthcare Safety Network from 2014, the first year of required use of the mucosal barrier injury laboratory-confirmed bloodstream infection (MBI-LCBI) definition, were analyzed to assess the impact of removing MBI-LCBI events from CLABSI rates. CLABSI rates decreased significantly in some location types after removing MBI-LCBI events, and MBI-LCBI events will be removed from publicly reported CLABSI rates. Published by Elsevier Inc.

  9. Consuming the savings: Water conservation in a vegetation barrier system at the Central Plateau in Burkina Faso

    OpenAIRE

    Spaan, W.

    2003-01-01

    The vast majority of land users at the Central Plateau of Burkina Faso make a living by farming small plots, where mainly staple crops are produced for subsistence use. Both area interventions and line interventions comprising indigenous techniques as well as introduced techniques can be encountered at the Central Plateau and have proved to be effective. There is a preference for semi-permeable line measures that slow down runoff and prevent water logging in wet periods.In order to ascertain ...

  10. Grunt language versus accent: the perceived communication barriers between international medical graduates and patients in Central Wheatbelt catchments.

    Science.gov (United States)

    Sommer, Jessica; Macdonald, William; Bulsara, Caroline; Lim, David

    2012-01-01

    Due to the chronic shortages of GPs in Australian rural and remote regions, considerable numbers of international medical graduates (IMG) have been recruited. IMG experience many difficulties when relocating to Australia with one of the most significant being effective GP-patient communication. Given that this is essential for effective consultation it can have a substantial impact on health care. A purposive sample of seven practising GPs (five IMG, two Australian-trained doctors (ATD)) was interviewed using a semistructured face-to-face interviewing technique. GPs from Nigeria, Egypt, United Kingdom, India, Singapore and Australia participated. Interviews were transcribed and then coded. The authors used qualitative thematic analysis of interview transcripts to identify common themes. IMG-patient communication barriers were considered significant in the Wheatbelt region as identified by both IMG and ATD. ATD indicated they were aware of IMG-patient communication issues resulting in subsequent consults with patients to explain results and diagnoses. Significantly, a lack of communication between ATD and IMG also emerged, creating a further barrier to effective communication. Analysis of the data generated several important findings that rural GP networks should consider when integrating new IMG into the community. Addressing the challenges related to cross-cultural differences should be a priority, in order to enable effective communication. More open communication between ATD and IMG about GP-patient communication barriers and education programs around GP-patient communication would help both GP and patient satisfaction.

  11. Consuming the savings : Water Conservation in a Vegetation Barrier System at the Central Plateau in Burkina Faso

    NARCIS (Netherlands)

    Spaan, W.P.

    2003-01-01

    The vast majority of land users at the Central Plateau of Burkina Faso make a living by farming small plots, where mainly staple crops are produced for subsistence use. Both area interventions and line interventions comprising indigenous techniques as well as introduced techniques can be encountered

  12. Uptake of influenza vaccination, awareness and its associated barriers among medical students of a University Hospital in Central Saudi Arabia.

    Science.gov (United States)

    Abalkhail, Mohammed S; Alzahrany, Mohannad S; Alghamdi, Khaled A; Alsoliman, Muath A; Alzahrani, Mosa A; Almosned, Badr S; Gosadi, Ibrahim M; Tharkar, Shabana

    Outbreaks of influenza epidemics are common but influenza vaccination is sub-optimal among the healthcare staff including the medical students. The study aims to assess the rate of vaccine uptake among medical students, its associated barriers and levels of awareness. A cross sectional study was done at a University Hospital in Saudi Arabia on 421 medical students by self administered questionnaire from February to March 2015. The immunization rate of seasonal influenza vaccine was just 20.7% in 2015, while it was 57% for cumulative of previous three-year period. The intended uptake among those offered vaccination was 68%. The significant determinants of vaccine uptake were clinical years of medical study (pinfluencing vaccine uptake decision were health department guidelines, medical training, social and media influence. Barriers of vaccination constituted, assumption of not being at risk of influenza (37.9%), vaccine side effects (28.9%), questioned effectiveness of the vaccine (14.5%), and inability to allocate time (11%). Knowledge levels were unsatisfactory and males scored lower (5.4±1.7) than females (6.5±1.4) out of total score of 9. Both knowledge and uptake of annual influenza vaccination was inadequate. Policy makers can formulate strategies with a focus on larger coverage of medical students. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  13. Great Apes

    Science.gov (United States)

    Sleeman, Jonathan M.; Cerveny, Shannon

    2014-01-01

    Anesthesia of great apes is often necessary to conduct diagnostic analysis, provide therapeutics, facilitate surgical procedures, and enable transport and translocation for conservation purposes. Due to the stress of remote delivery injection of anesthetic agents, recent studies have focused on oral delivery and/or transmucosal absorption of preanesthetic and anesthetic agents. Maintenance of the airway and provision of oxygen is an important aspect of anesthesia in great ape species. The provision of analgesia is an important aspect of the anesthesia protocol for any procedure involving painful stimuli. Opioids and nonsteroidal anti-inflammatory drugs (NSAIDs) are often administered alone, or in combination to provide multi-modal analgesia. There is increasing conservation management of in situ great ape populations, which has resulted in the development of field anesthesia techniques for free-living great apes for the purposes of translocation, reintroduction into the wild, and clinical interventions.

  14. On the protection and operation of nuclear power plants and great structures in Central Europe with respect to the tectonics of European Alps

    International Nuclear Information System (INIS)

    Nedoma, J.

    1991-01-01

    The aim of the study is to show that the financial resources needed for exploitation of the energetical resources as well as for the security of great energetical structures (i.e. nuclear power plants (NPP), deep mines, great waterdams, etc.), can be employed with high efficiency only when using appropriate basic and applied geological and geophysical investigations. One can only by this way save money expended during the last years to great structures built in critical regions. The breakdown of the Chernobyl NPP and the catastrophic earthquake in Armenia as well as the construction of a NPP there, situated on the Ararat deep fault, in a relatively small distance from the earthquake region, warn us and constitute the main reason for the realization of the research programme presented here as well as for the recommendation of this research programme to be solved within the framework of a Pentagonal group. (author) 13 refs.; 2 figs

  15. Russia, China, and the United States in Central Asia: Prospects for Great Power Competition and Cooperation in the Shadow of the Georgian Crisis

    Science.gov (United States)

    2009-02-01

    energy, public health, and food safety) shape Chinese foreign relations with neighboring states. Professor Wishnick also writes about great power...Dismisses Georgia’s Leader as ‘Political Corpse’,” The New York Times, September 3, 2008, p. A10; Ellen Barry, “Russians with Pumpkins Protest Many U.S

  16. Hypoxic Stress and Inflammatory Pain Disrupt Blood-Brain Barrier Tight Junctions: Implications for Drug Delivery to the Central Nervous System.

    Science.gov (United States)

    Lochhead, Jeffrey J; Ronaldson, Patrick T; Davis, Thomas P

    2017-07-01

    A functional blood-brain barrier (BBB) is necessary to maintain central nervous system (CNS) homeostasis. Many diseases affecting the CNS, however, alter the functional integrity of the BBB. It has been shown that various diseases and physiological stressors can impact the BBB's ability to selectively restrict passage of substances from the blood to the brain. Modifications of the BBB's permeability properties can potentially contribute to the pathophysiology of CNS diseases and result in altered brain delivery of therapeutic agents. Hypoxia and/or inflammation are central components of a number of diseases affecting the CNS. A number of studies indicate hypoxia or inflammatory pain increase BBB paracellular permeability, induce changes in the expression and/or localization of tight junction proteins, and affect CNS drug uptake. In this review, we look at what is currently known with regard to BBB disruption following a hypoxic or inflammatory insult in vivo. Potential mechanisms involved in altering tight junction components at the BBB are also discussed. A more detailed understanding of the mediators involved in changing BBB functional integrity in response to hypoxia or inflammatory pain could potentially lead to new treatments for CNS diseases with hypoxic or inflammatory components. Additionally, greater insight into the mechanisms involved in TJ rearrangement at the BBB may lead to novel strategies to pharmacologically increase delivery of drugs to the CNS.

  17. Cold-front driven storm erosion and overwash in the central part of the Isles Dernieres, a Louisiana barrier-island arc

    Science.gov (United States)

    Dingler, J.R.; Reiss, T.E.

    1990-01-01

    Tropical and extratropical storms produce significant erosion on the barrier islands of Louisiana. Over the past 100 years, such storms have produced at least 2 km of northward beach-face retreat and the loss of 63% of the surface area of the Isles Dernieres, a low-lying barrier-island arc along the central Louisiana coast. Elevations on the islands within the arc are typically less than 2 m above mean sea level. The islands typically have a washover-flat topography with occasional, poorly developed, dune-terrace topography consisting of low-lying and broken dunes. The central part of the arc consists of salt-marsh deposits overlain by washover sands along the Gulf of Mexico shoreline. Sand thicknesses range from zero behind the beach, to less than 2 m under the berm crest, and back to zero in the first nearshore trough. The sand veneer is sufficiently thin that storms can strip all the sand from the beach face, exposing the underlying marsh deposits. The geomorphic changes produced by cold fronts, a type of extratropical storm that commonly affect the Isles Dernieres between late fall and early spring are described. Between August 1986 and September 1987, repeated surveys along eleven shore-normal transects that covered 400 m of shoreline revealed the timing and extent of cold-front-produced beach change along a typical section of the central Isles Dernieres. During the study period, the beach face retreated approximately 20 m during the cold-front season but did not rebuild during the subsequent summer. Because the volume of sand deposited on the backshore (5600 m3) was less than the volume of material lost from the beach face (19,200 m3), approximately 13,600 m3 of material disappeared. Assuming that underlying marsh deposits decrease in volume in direct proportion to the amount of beach-face retreat, an estimate of the mud loss during the study period is 14,000 m3. Thus, the decrease in volume along the profiles can be accounted for without removing any sand

  18. Recurrent slow slip events as a barrier to the northward rupture propagation of the 2016 Pedernales earthquake (Central Ecuador)

    Science.gov (United States)

    Vaca, Sandro; Vallée, Martin; Nocquet, Jean-Mathieu; Battaglia, Jean; Régnier, Marc

    2018-01-01

    The northern Ecuador segment of the Nazca/South America subduction zone shows spatially heterogeneous interseismic coupling. Two highly coupled zones (0.4° S-0.35° N and 0.8° N-4.0° N) are separated by a low coupled area, hereafter referred to as the Punta Galera-Mompiche Zone (PGMZ). Large interplate earthquakes repeatedly occurred within the coupled zones in 1958 (Mw 7.7) and 1979 (Mw 8.1) for the northern patch and in 1942 (Mw 7.8) and 2016 (Mw 7.8) for the southern patch, while the whole segment is thought to have rupture during the 1906 Mw 8.4-8.8 great earthquake. We find that during the last decade, the PGMZ has experienced regular and frequent seismic swarms. For the best documented sequence (December 2013-January 2014), a joint seismological and geodetic analysis reveals a six-week-long Slow Slip Event (SSE) associated with a seismic swarm. During this period, the microseismicity is organized into families of similar earthquakes spatially and temporally correlated with the evolution of the aseismic slip. The moment release (3.4 × 1018 Nm, Mw 6.3), over a 60 × 40 km area, is considerably larger than the moment released by earthquakes (5.8 × 1015 Nm, Mw 4.4) during the same time period. In 2007-2008, a similar seismic-aseismic episode occurred, with higher magnitudes both for the seismic and aseismic processes. Cross-correlation analyses of the seismic waveforms over a 15 years-long period further suggest a 2-year repeat time for seismic swarms, which also implies that SSEs recurrently affect this area. Such SSEs contribute to release the accumulated stress, likely explaining why the 2016 Pedernales earthquake did not propagate northward into the PGMZ.

  19. Great Expectations

    NARCIS (Netherlands)

    Dickens, Charles

    2005-01-01

    One of Dickens's most renowned and enjoyable novels, Great Expectations tells the story of Pip, an orphan boy who wishes to transcend his humble origins and finds himself unexpectedly given the opportunity to live a life of wealth and respectability. Over the course of the tale, in which Pip

  20. Great Lakes

    Science.gov (United States)

    Edsall, Thomas A.; Mac, Michael J.; Opler, Paul A.; Puckett Haecker, Catherine E.; Doran, Peter D.

    1998-01-01

    The Great Lakes region, as defined here, includes the Great Lakes and their drainage basins in Minnesota, Wisconsin, Illinois, Indiana, Ohio, Pennsylvania, and New York. The region also includes the portions of Minnesota, Wisconsin, and the 21 northernmost counties of Illinois that lie in the Mississippi River drainage basin, outside the floodplain of the river. The region spans about 9º of latitude and 20º of longitude and lies roughly halfway between the equator and the North Pole in a lowland corridor that extends from the Gulf of Mexico to the Arctic Ocean.The Great Lakes are the most prominent natural feature of the region (Fig. 1). They have a combined surface area of about 245,000 square kilometers and are among the largest, deepest lakes in the world. They are the largest single aggregation of fresh water on the planet (excluding the polar ice caps) and are the only glacial feature on Earth visible from the surface of the moon (The Nature Conservancy 1994a).The Great Lakes moderate the region’s climate, which presently ranges from subarctic in the north to humid continental warm in the south (Fig. 2), reflecting the movement of major weather masses from the north and south (U.S. Department of the Interior 1970; Eichenlaub 1979). The lakes act as heat sinks in summer and heat sources in winter and are major reservoirs that help humidify much of the region. They also create local precipitation belts in areas where air masses are pushed across the lakes by prevailing winds, pick up moisture from the lake surface, and then drop that moisture over land on the other side of the lake. The mean annual frost-free period—a general measure of the growing-season length for plants and some cold-blooded animals—varies from 60 days at higher elevations in the north to 160 days in lakeshore areas in the south. The climate influences the general distribution of wild plants and animals in the region and also influences the activities and distribution of the human

  1. Postseismic Gravity Change After the 2006-2007 Great Earthquake Doublet and Constraints on the Asthenosphere Structure in the Central Kuril Islands

    Science.gov (United States)

    Shin-Chan, Han; Sauber, Jeanne; Pollitz, Fred

    2016-01-01

    Large earthquakes often trigger viscoelastic adjustment for years to decades depending on the rheological properties and the nature and spatial extent of coseismic stress. The 2006 Mw8.3 thrust and 2007 Mw8.1 normal fault earthquakes of the central Kuril Islands resulted in significant postseismic gravity change in GRACE but without a discernible coseismic gravity change. The gravity increase of approximately 4 micro-Gal, observed consistently from various GRACE solutions around the epicentral area during 2007-2015, is interpreted as resulting from gradual seafloor uplift by (is) approximately 6 cm produced by postseismic relaxation. The GRACE data are best fit with a model of 25-35 km for the elastic thickness and approximately 10(exp 18) Pa s for the Maxwell viscosity of the asthenosphere. The large measurable postseismic gravity change (greater than coseismic change) emphasizes the importance of viscoelastic relaxation in understanding tectonic deformation and fault-locking scenarios in the Kuril subduction zone.

  2. Seven new species of Paleanotus (Annelida: Chrysopetalidae) described from Lizard Island, Great Barrier Reef, and coral reefs of northern Australia and the Indo-Pacific: two cryptic species pairs revealed between western Pacific Ocean and the eastern Indian Ocean.

    Science.gov (United States)

    Watson, Charlotte

    2015-09-18

    Morphological investigation into the paleate genus Paleanotus Schmarda 1861 of the family Chrysopetalidae from northern Australian coral reefs, primarily Lizard Island and outlying reefs, included a complex of very small, slender individuals (length < 5 mm). This complex resolved into 7 new species, described herein: Paleanotus inornatus n. sp., P. adornatus n. sp., P. chrysos n. sp., P. aquifolia n. sp., P. latifolia n. sp., P. silus n. sp., and P. silopsis n. sp. A key is provided to the new species and Paleanotus distinguished from Treptopale and Hyalopale, two closely related genera. Diagnostic features of the apical structure and shape of the notochaetal main paleae plus median paleae shape and raised rib pattern, differentiates each species from the other. Gametous states are described. Two cryptic species pairs (Paleanotus silopsis n. sp. and P. silus n. sp.; Paleanotus aquifolia n. sp. and P. latifolia n. sp.) were identified. In each case one species is restricted to either the NE or NW Australian coast. In each pair the most eastern point for the NW Australian species range occurs at Darwin, western Arnhemland, Northern Territory. Additional material for each species pair extends their respective ranges northwards: NW Australia to Thailand, Andaman Sea, eastern Indian Ocean or NE Australia, Great Barrier Reef to the Philippines, western Pacific Ocean. Cryptic morphology and potential genetic diversity is discussed in Paleanotus inornatus n. sp. and P. adornatus n. sp. that possess overlapping widespread distribution patterns across northern Australia and Indo-Pacific reefs. The smallest bodied taxon, Paleanotus chrysos n. sp. is the only species with a Coral Sea range encompassing Lizard Island, Heron Island and New Caledonia.

  3. Co-Seismic Gravity Gradient Changes of the 2006-2007 Great Earthquakes in the Central Kuril Islands from GRACE Observations

    Science.gov (United States)

    Rahimi, A.; Shahrisvand, M.

    2017-09-01

    GRACE satellites (the Gravity Recovery And climate Experiment) are very useful sensors to extract gravity anomalies after earthquakes. In this study, we reveal co-seismic signals of the two combined earthquakes, the 2006 Mw8.3 thrust and 2007 Mw8.1 normal fault earthquakes of the central Kuril Islands from GRACE observations. We compute monthly full gravitational gradient tensor in the local north-east-down frame for Kuril Islands earthquakes without spatial averaging and de-striping filters. Some of gravitational gradient components (e.g. ΔVxx, ΔVxz) enhance high frequency components of the earth gravity field and reveal more details in spatial and temporal domain. Therefore, co-seismic activity can be better illustrated. For the first time, we show that the positive-negative-positive co-seismic ΔVxx due to the Kuril Islands earthquakes ranges from - 0.13 to + 0.11 milli Eötvös, and ΔVxz shows a positive-negative-positive pattern ranges from - 0.16 to + 0.13 milli Eötvös, agree well with seismic model predictions.

  4. Postseismic gravity change after the 2006–2007 great earthquake doublet and constraints on the asthenosphere structure in the central Kuril Islands

    Science.gov (United States)

    Han, Shin-Chan; Sauber, Jeanne; Pollitz, Fred

    2016-01-01

    Large earthquakes often trigger viscoelastic adjustment for years to decades depending on the rheological properties and the nature and spatial extent of coseismic stress. The 2006 Mw8.3 thrust and 2007 Mw8.1 normal fault earthquakes of the central Kuril Islands resulted in significant postseismic gravity change in Gravity Recovery and Climate Experiment (GRACE) but without a discernible coseismic gravity change. The gravity increase of ~4 μGal, observed consistently from various GRACE solutions around the epicentral area during 2007–2015, is interpreted as resulting from gradual seafloor uplift by ~6 cm produced by postseismic relaxation. The GRACE data are best fit with a model of 25–35 km for the elastic thickness and ~1018 Pa s for the Maxwell viscosity of the asthenosphere. The large measurable postseismic gravity change (greater than coseismic change) emphasizes the importance of viscoelastic relaxation in understanding tectonic deformation and fault-locking scenarios in the Kuril subduction zone.

  5. Uranium resources in fine-grained carbonaceous rocks of the Great Divide Basin, south-central Wyoming. National Uranium Resource Evaluation

    International Nuclear Information System (INIS)

    Burger, J.A.; Roe, L.M. II; Hacke, C.M.; Mosher, M.M.

    1982-11-01

    The uranium resources of the fine-grained carbonaceous rocks of the Great Divide Basin in southern Wyoming were assessed. The assessment was based primarily on data from some 600 boreholes. The data included information from geophysical logs, lithologic logs and cores, and drill cuttings. The cores and cuttings were analyzed for chemical U 3 O 8 , radiometric U, Th and trace elements. Selected samples were examined by thin section, sieve analysis, x-ray, SEM, ion probe, and alpha track methods. The uranium is associated with fine-grained carbonaceous shales, siltstones, mudstones, and coals in radioactive zones 5 to 50 ft thick that are continuous over broad areas. These rocks have a limited stratigraphic range between the Red Desert tongue of the Wasatch Formation and the lower part of the Tipton tongue of the Green River Formation. Most of this uranium is syngenetic in origin, in part from the chelation of the uranium by organic material in lake-side swamps and in part as uranium in very fine detrital heavy minerals. The uraniferous fine-grained carbonaceous rocks that exceed a cutoff grade of 100 ppM eU 3 O 8 extend over an area of 542 mi 2 and locally to a depth of approximately 2000 ft. The uraniferous area is roughly ellipical and embraces the zone of change between the piedmont and alluvial-fan facies and the lacustrine facies of the intertonguing Battle Spring, Wasatch, and Green River Formations. About 1.05 x 10 6 tons U 3 O 8 , based on gross-gamma logs not corrected for thorium, are assigned to the area in the first 500 ft; an estimated 3.49 x 10 6 tons are assigned to a depth of 1000 ft. These units also contain a substantial thorium resource that is also associated with fine-grained rocks. The thorium-to-uranium ratio generally ranges between 1 and 4. A thorium resource of 3.43 x 10 6 tons to a depth of 500 ft is estimated for the assessment area. 5 figures, 3 tables

  6. Experimental Methods and Transport Models for Drug Delivery across the Blood-Brain Barrier

    OpenAIRE

    Fu, Bingmei M

    2012-01-01

    The blood-brain barrier (BBB) is a dynamic barrier essential for maintaining the micro-environment of the brain. Although the special anatomical features of the BBB determine its protective role for the central nervous system (CNS) from blood-born neurotoxins, however, the BBB extremely limits the therapeutic efficacy of drugs into the CNS, which greatly hinders the treatment of major brain diseases. This review summarized the unique structures of the BBB, described a variety of in vivo and i...

  7. Groundwater model of the Great Basin carbonate and alluvial aquifer system version 3.0: Incorporating revisions in southwestern Utah and east central Nevada

    Science.gov (United States)

    Brooks, Lynette E.

    2017-12-01

    The groundwater model described in this report is a new version of previously published steady-state numerical groundwater flow models of the Great Basin carbonate and alluvial aquifer system, and was developed in conjunction with U.S. Geological Survey studies in Parowan, Pine, and Wah Wah Valleys, Utah. This version of the model is GBCAAS v. 3.0 and supersedes previous versions. The objectives of the model for Parowan Valley were to simulate revised conceptual estimates of recharge and discharge, to estimate simulated aquifer storage properties and the amount of reduction in storage as a result of historical groundwater withdrawals, and to assess reduction in groundwater withdrawals necessary to mitigate groundwater-level declines in the basin. The objectives of the model for the area near Pine and Wah Wah Valleys were to recalibrate the model using new observations of groundwater levels and evapotranspiration of groundwater; to provide new estimates of simulated recharge, hydraulic conductivity, and interbasin flow; and to simulate the effects of proposed groundwater withdrawals on the regional flow system. Meeting these objectives required the addition of 15 transient calibration stress periods and 14 projection stress periods, aquifer storage properties, historical withdrawals in Parowan Valley, and observations of water-level changes in Parowan Valley. Recharge in Parowan Valley and withdrawal from wells in Parowan Valley and two nearby wells in Cedar City Valley vary for each calibration stress period representing conditions from March 1940 to November 2013. Stresses, including recharge, are the same in each stress period as in the steady-state stress period for all areas outside of Parowan Valley. The model was calibrated to transient conditions only in Parowan Valley. Simulated storage properties outside of Parowan Valley were set the same as the Parowan Valley properties and are not considered calibrated. Model observations in GBCAAS v. 3.0 are

  8. A 2D-QSPR approach to predict blood-brain barrier penetration of drugs acting on the central nervous system

    Directory of Open Access Journals (Sweden)

    Matheus Malta de Sá

    2010-12-01

    Full Text Available Drugs acting on the central nervous system (CNS have to cross the blood-brain barrier (BBB in order to perform their pharmacological actions. Passive BBB diffusion can be partially expressed by the blood/brain partition coefficient (logBB. As the experimental evaluation of logBB is time and cost consuming, theoretical methods such as quantitative structure-property relationships (QSPR can be useful to predict logBB values. In this study, a 2D-QSPR approach was applied to a set of 28 drugs acting on the CNS, using the logBB property as biological data. The best QSPR model [n = 21, r = 0.94 (r² = 0.88, s = 0.28, and Q² = 0.82] presented three molecular descriptors: calculated n-octanol/water partition coefficient (ClogP, polar surface area (PSA, and polarizability (α. Six out of the seven compounds from the test set were well predicted, which corresponds to good external predictability (85.7%. These findings can be helpful to guide future approaches regarding those molecular descriptors which must be considered for estimating the logBB property, and also for predicting the BBB crossing ability for molecules structurally related to the investigated set.Fármacos que atuam no sistema nervoso central (SNC devem atravessar a barreira hematoencefálica (BHE para exercerem suas ações farmacológicas. A difusão passiva através da BHE pode ser parcialmente expressa pelo coeficiente de partição entre os compartimentos encefálico e sanguíneo (logBB, brain/blood partition coefficient. Considerando-se que a avaliação experimental de logBB é dispendiosa e demorada, métodos teóricos como estudos das relações entre estrutura química e propriedade (QSPR, Quantitative Structure-Property Relationships podem ser utilizados na previsão dos valores de logBB. Neste estudo, uma abordagem de QSPR-2D foi aplicada a um conjunto de 28 moléculas com ação central, usando logBB como propriedade biológica. O melhor modelo de QSPR [n = 21, r = 0,94 (r

  9. Central Asia: A New Great Game?

    Science.gov (United States)

    1996-06-17

    as natural gas extraction, chemicals, agricultural products processing, hotel construction , and banking. In June 1994 India offered Turkmenistan a 10...34 promising cooperation in fighting terrorism, arms and drug trafficking and extremist ideologies.48 Specific investment projects included hotel ... construction in Tashkent, Samarkand, and Bukhara. In 1992 India signed a group of agreements with Almaty to develop its textile and hotel industries. India

  10. Information barriers

    International Nuclear Information System (INIS)

    Fuller, J.L.; Wolford, J.

    2001-01-01

    policy and security reviews. These elements are: Supplier of Integrated Measurement System and Information Barrier; Central Processing Units (CPUs); Non-CPU Equipment; Procedures; Electronic Emanations; Location of Barriers(s); Software, Firmware, CPU Operating Systems; Storage, Authentication, and Disposition of Data and Data Media; Inputs and Outputs. Technical specialists from cooperating parties must be able to prove to their respective policy makers that it is not overly difficult to make measurements of sensitive objects without revealing classified information. Without technical measures to inspect classified nuclear items and materials, it will be extremely difficult to reduce stockpiles in a manner that does not impact the security of Russia and the United States. The importance of successfully developing and implementing effective information barrier methods and procedures can not be overstated. A cooperative program is a good investment in U.S., Russian, and international security and threat reduction. The utility of radiation detection systems to characterize known and unknown quantities of nuclear material is without dispute. Such systems offer a powerful technological tool for warhead dismantlement transparency, and bilateral and international safeguards. There are many examples of their use in the international community today. The problem is the application of such systems with a host country's sensitive nuclear material. If it is one objective of any bilateral or trilateral arrangement to prevent the release of classified nuclear data to the inspecting party when inspecting sensitive materials, then some form of information barrier must be integrated into the measurement system. Through a set of well-defined principles as described above, the protection of such information is not a difficult problem to solve. Perhaps the more difficult problem is providing an inspecting party with confidence, for the case where the host supplies and/or certifies the

  11. Estimating the Exposure of Coral Reefs and Seagrass Meadows to Land-Sourced Contaminants in River Flood Plumes of the Great Barrier Reef: Validating a Simple Satellite Risk Framework with Environmental Data

    Directory of Open Access Journals (Sweden)

    Caroline Petus

    2016-03-01

    Full Text Available River runoff and associated flood plumes (hereafter river plumes are a major source of land-sourced contaminants to the marine environment, and are a significant threat to coastal and marine ecosystems worldwide. Remote sensing monitoring products have been developed to map the spatial extent, composition and frequency of occurrence of river plumes in the Great Barrier Reef (GBR, Australia. There is, however, a need to incorporate these monitoring products into Risk Assessment Frameworks as management decision tools. A simple Satellite Risk Framework has been recently proposed to generate maps of potential risk to seagrass and coral reef ecosystems in the GBR focusing on the Austral tropical wet season. This framework was based on a “magnitude × likelihood” risk management approach and GBR plume water types mapped from satellite imagery. The GBR plume water types (so called “Primary” for the inshore plume waters, “Secondary” for the midshelf-plume waters and “Tertiary” for the offshore plume waters represent distinct concentrations and combinations of land-sourced and marine contaminants. The current study aimed to test and refine the methods of the Satellite Risk Framework. It compared predicted pollutant concentrations in plume water types (multi-annual average from 2005–2014 to published ecological thresholds, and combined this information with similarly long-term measures of seagrass and coral ecosystem health. The Satellite Risk Framework and newly-introduced multi-annual risk scores were successful in demonstrating where water conditions were, on average, correlated to adverse biological responses. Seagrass meadow abundance (multi-annual change in % cover was negatively correlated to the multi-annual risk score at the site level (R2 = 0.47, p < 0.05. Relationships between multi-annual risk scores and multi-annual changes in proportional macroalgae cover (as an index for coral reef health were more complex (R2 = 0.04, p

  12. The biological significance of brain barrier mechanisms: help or hindrance in drug delivery to the central nervous system? [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Norman R. Saunders

    2016-03-01

    Full Text Available Barrier mechanisms in the brain are important for its normal functioning and development. Stability of the brain’s internal environment, particularly with respect to its ionic composition, is a prerequisite for the fundamental basis of its function, namely transmission of nerve impulses. In addition, the appropriate and controlled supply of a wide range of nutrients such as glucose, amino acids, monocarboxylates, and vitamins is also essential for normal development and function. These are all cellular functions across the interfaces that separate the brain from the rest of the internal environment of the body. An essential morphological component of all but one of the barriers is the presence of specialized intercellular tight junctions between the cells comprising the interface: endothelial cells in the blood-brain barrier itself, cells of the arachnoid membrane, choroid plexus epithelial cells, and tanycytes (specialized glial cells in the circumventricular organs. In the ependyma lining the cerebral ventricles in the adult brain, the cells are joined by gap junctions, which are not restrictive for intercellular movement of molecules. But in the developing brain, the forerunners of these cells form the neuroepithelium, which restricts exchange of all but the smallest molecules between cerebrospinal fluid and brain interstitial fluid because of the presence of strap junctions between the cells. The intercellular junctions in all these interfaces are the physical basis for their barrier properties. In the blood-brain barrier proper, this is combined with a paucity of vesicular transport that is a characteristic of other vascular beds. Without such a diffusional restrain, the cellular transport mechanisms in the barrier interfaces would be ineffective. Superimposed on these physical structures are physiological mechanisms as the cells of the interfaces contain various metabolic transporters and efflux pumps, often ATP-binding cassette (ABC

  13. Barriers to access to opioid medicines for patients with opioid dependence : a review of legislation and regulations in eleven central and eastern European countries

    NARCIS (Netherlands)

    Vranken, Marjolein J M; Mantel-Teeuwisse, Aukje K; Jünger, Saskia; Radbruch, Lukas; Scholten, Willem; Lisman, John A; Subataite, Marija; Schutjens, Marie-Hélène D B

    BACKGROUND AND AIMS: Barriers linked to drug control systems are considered to contribute to inequitable access to controlled medicines, leaving millions of people in pain and suffering. Most studies focus on access to opioids for the treatment of severe (cancer) pain. This study aims to identify

  14. 'Before reaching the last mile'- Knowledge, attitude, practice and perceived barriers related to tuberculosis directly observed therapy among ASHA workers in Central India: A mixed method study.

    Science.gov (United States)

    Singh, Akash Ranjan; Pakhare, Abhijit; Kokane, Arun M; Shewade, Hemant Deepak; Chauhan, Ashish; Singh, Abhishek; Gangwar, Arti; Thakur, Prahlad Singh

    2017-12-01

    Community-based direct observed treatment (DOT) providers are an important bridge for the national tuberculosis programme in India to reach the unreached. The present study has explored the knowledge, attitude, practice and barriers perceived by the community-based DOT providers. Mixed-methods study design was used among 41 community-based DOT providers (Accredited Social Health Activist (ASHAs)) working in 67 villages from a primary health center in Raisen district of Madhya Pradesh, India. The cross-sectional quantitative component assessed the knowledge and practices and three focus-group discussions explored the attitude and perceived barriers related to DOT provision. 'Adequate knowledge' and 'satisfactory practice' related to DOT provision was seen in 14 (34%) and 13 (32%) ASHAs respectively. Only two (5%) received any amount of honorarium for completion of DOT in last 3years. The focus-group discussions revealed unfavourable attitude; inadequate training and supervision, non-payment of honorarium, issues related to assured services after referral and patient related factors as the barriers to satisfactory practice of DOT. Study revealed inadequate knowledge and unsatisfactory practice related to DOT provision among ASHAs. Innovations addressing the perceived barriers to improve practice of DOT provision by ASHAs are urgently required. Copyright © 2017 Ministry of Health, Saudi Arabia. Published by Elsevier Ltd. All rights reserved.

  15. Barriers in access to healthcare in countries with different health systems. A cross-sectional study in municipalities of central Colombia and north-eastern Brazil.

    Science.gov (United States)

    Garcia-Subirats, Irene; Vargas, Ingrid; Mogollón-Pérez, Amparo Susana; De Paepe, Pierre; da Silva, Maria Rejane Ferreira; Unger, Jean Pierre; Vázquez, María Luisa

    2014-04-01

    There are few comprehensive studies available on barriers encountered from the initial seeking of healthcare through to the resolution of the health problem; in other words, on access in its broad domain. For Colombia and Brazil, countries with different healthcare systems but common stated principles, there have been no such analyses to date. This paper compares factors that influence access in its broad domain in two municipalities of each country, by means of a cross-sectional study based on a survey of a multistage probability sample of people who had had at least one health problem within the last three months (2163 in Colombia and 2155 in Brazil). The results reveal important barriers to healthcare access in both samples, with notable differences between and within countries, once differences in sociodemographic characteristics and health needs are accounted for. In the Colombian study areas, the greatest barriers were encountered in initial access to healthcare and in resolving the problem, and similarly when entering the health service in the Brazilian study areas. Differences can also be detected in the use of services: in Colombia greater geographical and economic barriers and the need for authorization from insurers are more relevant, whereas in Brazil, it is the limited availability of health centres, doctors and drugs that leads to longer waiting times. There are also differences according to enrolment status and insurance scheme in Colombia, and between areas in Brazil. The barriers appear to be related to the Colombian system's segmented, non-universal nature, and to the involvement of insurance companies, and to chronic underfunding of the public system in Brazil. Further research is required, but the results obtained reveal critical points to be tackled by health policies in both countries. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  16. Meningeal mast cells affect early T cell central nervous system infiltration and blood-brain barrier integrity through TNF: a role for neutrophil recruitment?

    Science.gov (United States)

    Sayed, Blayne A; Christy, Alison L; Walker, Margaret E; Brown, Melissa A

    2010-06-15

    Mast cells contribute to the pathogenesis of experimental autoimmune encephalomyelitis, a rodent model of the human demyelinating disease multiple sclerosis. Yet their site and mode of action is unknown. In both diseases, myelin-specific T cells are initially activated in peripheral lymphoid organs. However, for disease to occur, these cells must enter the immunologically privileged CNS through a breach in the relatively impermeable blood-brain barrier. In this study, we demonstrate that a dense population of resident mast cells in the meninges, structures surrounding the brain and spinal cord, regulate basal CNS barrier function, facilitating initial T cell CNS entry. Through the expression of TNF, mast cells recruit an early wave of neutrophils to the CNS. We propose that neutrophils in turn promote the blood-brain barrier breach and together with T cells lead to further inflammatory cell influx and myelin damage. These findings provide specific targets for intervention in multiple sclerosis as well as other immune-mediated CNS diseases.

  17. The Great Recession was not so Great

    NARCIS (Netherlands)

    van Ours, J.C.

    2015-01-01

    The Great Recession is characterized by a GDP-decline that was unprecedented in the past decades. This paper discusses the implications of the Great Recession analyzing labor market data from 20 OECD countries. Comparing the Great Recession with the 1980s recession it is concluded that there is a

  18. Great Lakes Science Center

    Data.gov (United States)

    Federal Laboratory Consortium — Since 1927, Great Lakes Science Center (GLSC) research has provided critical information for the sound management of Great Lakes fish populations and other important...

  19. Soluble CD40 ligand contributes to blood-brain barrier breakdown and central nervous system inflammation in multiple sclerosis and neuromyelitis optica spectrum disorder.

    Science.gov (United States)

    Masuda, Hiroki; Mori, Masahiro; Uchida, Tomohiko; Uzawa, Akiyuki; Ohtani, Ryohei; Kuwabara, Satoshi

    2017-04-15

    Soluble CD40 ligand (sCD40L) is reported to disrupt the blood-brain barrier (BBB). Cerebrospinal fluid (CSF) and serum sCD40L levels were measured in 29 multiple sclerosis (MS), 29 neuromyelitis optica spectrum disorder (NMOSD), and 27 disease control (DC) patients. In MS, serum sCD40L levels were higher than in DCs and positively correlated with the CSF/serum albumin ratio (Qalb). In NMOSD, CSF sCD40L levels were significantly increased compared to DCs, and were correlated to Qalb, CSF cell counts, protein concentrations, and interleukin-6 levels. sCD40L could be involved in BBB disruption in MS, whereas it may contribute to CNS inflammation in NMOSD. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Credit spread variability in U.S. business cycles: the Great Moderation versus the Great Recession

    OpenAIRE

    Hylton Hollander; Guangling Liu

    2014-01-01

    This paper establishes the prevailing financial factors that influence credit spread variability, and its impact on the U.S. business cycle over the Great Moderation and Great Recession periods. To do so, we develop a dynamic general equilibrium framework with a central role of financial intermediation and equity assets. Over the Great Moderation and Great Recession periods, we find an important role for bank market power (sticky rate adjustments and loan rate markups) on credit spread variab...

  1. Credit spread variability in U.S. business cycles: The Great Moderation versus the Great Recession

    OpenAIRE

    Hylton Hollander and Guangling Liu

    2014-01-01

    This paper establishes the prevailing financial factors that influence credit spread variability, and its impact on the U.S. business cycle over the Great Moderation and Great Recession periods. To do so, we develop a dynamic general equilibrium framework with a central role of financial intermediation and equity assets. Over the Great Moderation and Great Recession periods, we find an important role for bank market power (sticky rate adjustments and loan rate markups) on credit spread variab...

  2. The Great Womanhunt.

    Science.gov (United States)

    Seltz-Petrash, Ann

    1980-01-01

    Discusses the aggressive recruitment of women by engineering schools and firms, progress in eliminating sex discrimination barriers, and lingering sex bias problems in the field. Offers suggestions to new women engineering graduates. (SK)

  3. Examples of great cross-border floods in Central Europe and lessons learnt (case studies of floods from September and November 1890 on the occasion of their 120th anniversary)

    Czech Academy of Sciences Publication Activity Database

    Munzar, Jan; Deutsch, M.; Ondráček, Stanislav; Kallabová, Eva

    2010-01-01

    Roč. 18, č. 4 (2010), s. 21-29 ISSN 1210-8812 Institutional research plan: CEZ:AV0Z30860518 Keywords : cross-border floods 1890 * Central Europe * lessons learnt Subject RIV: DA - Hydrology ; Limnology http://www.geonika.cz/CZ/CZresearch/CZMgrArchive.html

  4. Assessing the impacts of sea-level rise and precipitation change on the surficial aquifer in the low-lying coastal alluvial plains and barrier islands, east-central Florida (USA)

    Science.gov (United States)

    Xiao, Han; Wang, Dingbao; Hagen, Scott C.; Medeiros, Stephen C.; Hall, Carlton R.

    2016-11-01

    A three-dimensional variable-density groundwater flow and salinity transport model is implemented using the SEAWAT code to quantify the spatial variation of water-table depth and salinity of the surficial aquifer in Merritt Island and Cape Canaveral Island in east-central Florida (USA) under steady-state 2010 hydrologic and hydrogeologic conditions. The developed model is referred to as the `reference' model and calibrated against field-measured groundwater levels and a map of land use and land cover. Then, five prediction/projection models are developed based on modification of the boundary conditions of the calibrated `reference' model to quantify climate change impacts under various scenarios of sea-level rise and precipitation change projected to 2050. Model results indicate that west Merritt Island will encounter lowland inundation and saltwater intrusion due to its low elevation and flat topography, while climate change impacts on Cape Canaveral Island and east Merritt Island are not significant. The SEAWAT models developed for this study are useful and effective tools for water resources management, land use planning, and climate-change adaptation decision-making in these and other low-lying coastal alluvial plains and barrier island systems.

  5. Great Lakes Literacy Principles

    Science.gov (United States)

    Fortner, Rosanne W.; Manzo, Lyndsey

    2011-03-01

    Lakes Superior, Huron, Michigan, Ontario, and Erie together form North America's Great Lakes, a region that contains 20% of the world's fresh surface water and is home to roughly one quarter of the U.S. population (Figure 1). Supporting a $4 billion sport fishing industry, plus $16 billion annually in boating, 1.5 million U.S. jobs, and $62 billion in annual wages directly, the Great Lakes form the backbone of a regional economy that is vital to the United States as a whole (see http://www.miseagrant.umich.edu/downloads/economy/11-708-Great-Lakes-Jobs.pdf). Yet the grandeur and importance of this freshwater resource are little understood, not only by people in the rest of the country but also by many in the region itself. To help address this lack of knowledge, the Centers for Ocean Sciences Education Excellence (COSEE) Great Lakes, supported by the U.S. National Science Foundation and the National Oceanic and Atmospheric Administration, developed literacy principles for the Great Lakes to serve as a guide for education of students and the public. These “Great Lakes Literacy Principles” represent an understanding of the Great Lakes' influences on society and society's influences on the Great Lakes.

  6. The Next Great Generation?

    Science.gov (United States)

    Brownstein, Andrew

    2000-01-01

    Discusses ideas from a new book, "Millennials Rising: The Next Great Generation," (by Neil Howe and William Strauss) suggesting that youth culture is on the cusp of a radical shift with the generation beginning with this year's college freshmen who are typically team oriented, optimistic, and poised for greatness on a global scale. Includes a…

  7. Barriers to knowledge sharing in Chinese healthcare referral services: an emergent theoretical model

    Science.gov (United States)

    Nunes, Miguel Baptista

    2016-01-01

    Background This paper reports on a research study that aims to identify and explain barriers to knowledge sharing (KS) in the provision of healthcare referral services in Chinese healthcare organisations. Design An inductive case study approach was employed, in which 24 healthcare professionals and workers from four healthcare organisations in the province of Hubei, Central China, were interviewed using semi-structured scripts. Results Through data analysis, 14 KS barriers emerged in four main themes: interpersonal trust barriers, communication barriers, management and leadership barriers, and inter-institutional barriers. A cause–consequence analysis of the identified barriers revealed that three of them are at the core of the majority of problems, namely, the absence of national and local policies for inter-hospital KS, lack of a specific hospital KS requirement, and lack of mutual acquaintance. Conclusions To resolve KS problems, it is of great importance that healthcare governance agencies, both at the national and regional levels, take leadership in the process of KS implementation by establishing specific and strong policies for inter-institutional KS in the referral process. This paper raises important issues that exceed academic interests and are important to healthcare professionals, hospital managers, and Information communication technology (ICT) managers in hospitals, as well as healthcare politicians and policy makers. PMID:26895146

  8. Barrier Systems

    NARCIS (Netherlands)

    Heteren, S. van

    2015-01-01

    Barrier-system dynamics are a function of antecedent topography and substrate lithology, Relative sea-level (RSL) changes, sediment availability and type, climate, vegetation type and cover, and various aero- and hydrodynamic processes during fair-weather conditions and extreme events. Global change

  9. Seasonal breaching of coastal barriers

    NARCIS (Netherlands)

    Tuan, Thieu Quang

    2007-01-01

    Natural or unintended breaching can be catastrophic, causing loss of human lives and damage to infrastructures, buildings and natural habitats. Quantitative understand-ing of coastal barrier breaching is therefore of great importance to vulnerability as-sessment of protection works as well as to

  10. Great Plains Wind Energy Transmission Development Project

    Energy Technology Data Exchange (ETDEWEB)

    Brad G. Stevens, P.E.; Troy K. Simonsen; Kerryanne M. Leroux

    2012-06-09

    In fiscal year 2005, the Energy & Environmental Research Center (EERC) received funding from the U.S. Department of Energy (DOE) to undertake a broad array of tasks to either directly or indirectly address the barriers that faced much of the Great Plains states and their efforts to produce and transmit wind energy at the time. This program, entitled Great Plains Wind Energy Transmission Development Project, was focused on the central goal of stimulating wind energy development through expansion of new transmission capacity or development of new wind energy capacity through alternative market development. The original task structure was as follows: Task 1 - Regional Renewable Credit Tracking System (later rescoped to Small Wind Turbine Training Center); Task 2 - Multistate Transmission Collaborative; Task 3 - Wind Energy Forecasting System; and Task 4 - Analysis of the Long-Term Role of Hydrogen in the Region. As carried out, Task 1 involved the creation of the Small Wind Turbine Training Center (SWTTC). The SWTTC, located Grand Forks, North Dakota, consists of a single wind turbine, the Endurance S-250, on a 105-foot tilt-up guyed tower. The S-250 is connected to the electrical grid on the 'load side' of the electric meter, and the power produced by the wind turbine is consumed locally on the property. Establishment of the SWTTC will allow EERC personnel to provide educational opportunities to a wide range of participants, including grade school through college-level students and the general public. In addition, the facility will allow the EERC to provide technical training workshops related to the installation, operation, and maintenance of small wind turbines. In addition, under Task 1, the EERC hosted two small wind turbine workshops on May 18, 2010, and March 8, 2011, at the EERC in Grand Forks, North Dakota. Task 2 involved the EERC cosponsoring and aiding in the planning of three transmission workshops in the midwest and western regions. Under Task

  11. In Vitro Blood-Brain Barrier Models-An Overview of Established Models and New Microfluidic Approaches

    DEFF Research Database (Denmark)

    Wolff, Anette; Antfolk, Maria; Brodin, Birger

    2015-01-01

    The societal need for new central nervous system (CNS) medicines is substantial, because of the global increase in life expectancy and the accompanying increase in age-related CNS diseases. Low blood-brain barrier (BBB) permeability has been one of the major causes of failure for new CNS drug can...... that the field may benefit greatly from developing standardized methodologies and initiating collaborative efforts on optimizing culture protocols. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci....

  12. Great Indoors Awards 2007

    Index Scriptorium Estoniae

    2007-01-01

    Hollandis Maastrichtis jagati 17. XI esimest korda rahvusvahelist auhinda The Great Indoors Award. Aasta sisekujundusfirmaks valiti Masamichi Katayama asutatud Wonderwall. Auhinna said veel Zaha Hadid, Heatherwick Studio, Ryui Nakamura Architects ja Item Idem

  13. Great Lakes Bathymetry

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Bathymetry of Lakes Michigan, Erie, Saint Clair, Ontario and Huron has been compiled as a component of a NOAA project to rescue Great Lakes lake floor geological and...

  14. Floating barrier

    Energy Technology Data Exchange (ETDEWEB)

    1968-05-06

    This floating barrier consists of relatively long elements which can be connected to form a practically continuous assembly. Each element consists of an inflatable tube with an apron of certain height, made of impregnated fabric which is resistant to ocean water and also to hydrocarbons. Means for connecting one element to the following one, and means for attaching ballast to the apron are also provided.

  15. Experimental methods and transport models for drug delivery across the blood-brain barrier.

    Science.gov (United States)

    Fu, Bingmei M

    2012-06-01

    The blood-brain barrier (BBB) is a dynamic barrier essential for maintaining the micro-environment of the brain. Although the special anatomical features of the BBB determine its protective role for the central nervous system (CNS) from blood-born neurotoxins, however, the BBB extremely limits the therapeutic efficacy of drugs into the CNS, which greatly hinders the treatment of major brain diseases. This review summarized the unique structures of the BBB, described a variety of in vivo and in vitro experimental methods for determining the transport properties of the BBB, e.g., the permeability of the BBB to water, ions, and solutes including nutrients, therapeutic agents and drug carriers, and presented newly developed mathematical models which quantitatively correlate the anatomical structures of the BBB with its barrier functions. Finally, on the basis of the experimental observations and the quantitative models, several strategies for drug delivery through the BBB were proposed.

  16. Saturable active efflux by p-glycoprotein and breast cancer resistance protein at the blood-brain barrier leads to nonlinear distribution of elacridar to the central nervous system.

    Science.gov (United States)

    Sane, Ramola; Agarwal, Sagar; Mittapalli, Rajendar K; Elmquist, William F

    2013-04-01

    The study objective was to investigate factors that affect the central nervous system (CNS) distribution of elacridar. Elacridar inhibits transport mediated by P-glycoprotein (P-gp) and breast cancer resistance protein (Bcrp) and has been used to study the influence of transporters on brain distribution of chemotherapeutics. Adequate distribution of elacridar across the blood-brain barrier (BBB) and into the brain parenchyma is necessary to target tumor cells in the brain that overexpress transporters and reside behind an intact BBB. We examined the role of P-gp and Bcrp on brain penetration of elacridar using Friend leukemia virus strain B wild-type, Mdr1a/b(-/-), Bcrp1(-/-), and Mdr1a/b(-/-)Bcrp1(-/-) mice. Initially, the mice were administered 2.5 mg/kg of elacridar intravenously, and the plasma and brain concentrations were determined. The brain-to-plasma partition coefficient of elacridar in the wild-type mice was 0.82, as compared with 3.5 in Mdr1a/b(-/-) mice, 6.6 in Bcrp1(-/-) mice, and 15 in Mdr1a/b(-/-)Bcrp1(-/-) mice, indicating that both P-gp and Bcrp limit the brain distribution of elacridar. The four genotypes were then administered increasing doses of elacridar, and the CNS distribution of elacridar was determined. The observed and model predicted maximum brain-to-plasma ratios (Emax) at the highest dose were not significantly different in all genotypes. However, the ED50 was lower for Mdr1a/b(-/-) mice compared with Bcrp1(-/-) mice. These findings correlate with the relative expression of P-gp and Bcrp at the BBB in these mice and demonstrate the quantitative enhancement in elacridar CNS distribution as a function of its dose. Overall, this study provides useful concepts for future applications of elacridar as an adjuvant therapy to improve targeting of chemotherapeutic agents to tumor cells in the brain parenchyma.

  17. Smart parking barrier

    KAUST Repository

    Alharbi, Abdulrazaq M.

    2016-01-01

    positioning of the movable parking barrier, and a parking controller configured to initiate movement of the parking barrier, via the barrier drive. The movable parking barrier can be positioned between a first position that restricts access to the parking

  18. The GREAT3 challenge

    International Nuclear Information System (INIS)

    Miyatake, H; Mandelbaum, R; Rowe, B

    2014-01-01

    The GRavitational lEnsing Accuracy Testing 3 (GREAT3) challenge is an image analysis competition that aims to test algorithms to measure weak gravitational lensing from astronomical images. The challenge started in October 2013 and ends 30 April 2014. The challenge focuses on testing the impact on weak lensing measurements of realistically complex galaxy morphologies, realistic point spread function, and combination of multiple different exposures. It includes simulated ground- and space-based data. The details of the challenge are described in [1], and the challenge website and its leader board can be found at http://great3challenge.info and http://great3.projects.phys.ucl.ac.uk/leaderboard/, respectively

  19. Nothing Great Is Easy

    OpenAIRE

    Stansbie, Lisa

    2014-01-01

    A solo exhibition of 13 pieces of art work.\\ud \\ud Nothing Great is Easy is an exhibition of sculpture, film, drawing and photography that proposes reconstructed narratives using the sport of swimming and in particular the collective interaction and identity of the channel swimmer. The work utilises the processes, rituals/rules, language and the apparatus of sport.\\ud \\ud “Nothing great is easy” are the words on the memorial to Captain Matthew Webb who was the first man to swim the English ch...

  20. The Great Mathematician Project

    Science.gov (United States)

    Goldberg, Sabrina R.

    2013-01-01

    The Great Mathematician Project (GMP) introduces both mathematically sophisticated and struggling students to the history of mathematics. The rationale for the GMP is twofold: first, mathematics is a uniquely people-centered discipline that is used to make sense of the world; and second, students often express curiosity about the history of…

  1. What great managers do.

    Science.gov (United States)

    Buckingham, Marcus

    2005-03-01

    Much has been written about the qualities that make a great manager, but most of the literature overlooks a fundamental question: What does a great manager actually do? While there are countless management styles, one thing underpins the behavior of all great managers. Above all, an exceptional manager comes to know and value the particular quirks and abilities of her employees. She figures out how to capitalize on her staffers' strengths and tweaks her environment to meet her larger goals. Such a specialized approach may seem like a lot of work. But in fact, capitalizing on each person's uniqueness can save time. Rather than encourage employees to conform to strict job descriptions that may include tasks they don't enjoy and aren't good at, a manager who develops positions for his staff members based on their unique abilities will be rewarded with behaviors that are far more efficient and effective than they would be otherwise. This focus on individuals also makes employees more accountable. Because staffers are evaluated on their particular strengths and weaknesses, they are challenged to take responsibility for their abilities and to hone them. Capitalizing on a person's uniqueness also builds a stronger sense of team. By taking the time to understand what makes each employee tick, a great manager shows that he sees his people for who they are. This personal investment not only motivates individuals but also galvanizes the entire team. Finally, this approach shakes up existing hierarchies, which leads to more creative thinking. To take great managing from theory to practice, the author says, you must know three things about a person: her strengths, the triggers that activate those strengths, and how she learns. By asking the right questions, squeezing the right triggers, and becoming aware of your employees' learning styles, you will discover what motivates each person to excel.

  2. Great magnetic storms

    International Nuclear Information System (INIS)

    Tsurutani, B.T.; Yen Te Lee; Tang, F.; Gonzalez, W.D.

    1992-01-01

    The five largest magnetic storms that occurred between 1971 and 1986 are studied to determine their solar and interplanetary causes. All of the events are found to be associated with high speed solar wind streams led by collisionless shocks. The high speed streams are clearly related to identifiable solar flares. It is found that (1) it is the extreme values of the southward interplanetary magnetic fields rather than solar wind speeds that are the primary causes of great magnetic storms, (2) shocked and draped sheath fields preceding the driver gas (magnetic cloud) are at least as effective in causing the onset of great magnetic storms (3 of 5 events ) as the strong fields within the driver gas itself, and (3) precursor southward fields ahead of the high speed streams allow the shock compression mechanism (item 2) to be particularly geoeffective

  3. The great intimidators.

    Science.gov (United States)

    Kramer, Roderick M

    2006-02-01

    After Disney's Michael Eisner, Miramax's Harvey Weinstein, and Hewlett-Packard's Carly Fiorina fell from their heights of power, the business media quickly proclaimed thatthe reign of abrasive, intimidating leaders was over. However, it's premature to proclaim their extinction. Many great intimidators have done fine for a long time and continue to thrive. Their modus operandi runs counter to a lot of preconceptions about what it takes to be a good leader. They're rough, loud, and in your face. Their tactics include invading others' personal space, staging tantrums, keeping people guessing, and possessing an indisputable command of facts. But make no mistake--great intimidators are not your typical bullies. They're driven by vision, not by sheer ego or malice. Beneath their tough exteriors and sharp edges are some genuine, deep insights into human motivation and organizational behavior. Indeed, these leaders possess political intelligence, which can make the difference between paralysis and successful--if sometimes wrenching--organizational change. Like socially intelligent leaders, politically intelligent leaders are adept at sizing up others, but they notice different things. Those with social intelligence assess people's strengths and figure out how to leverage them; those with political intelligence exploit people's weaknesses and insecurities. Despite all the obvious drawbacks of working under them, great intimidators often attract the best and brightest. And their appeal goes beyond their ability to inspire high performance. Many accomplished professionals who gravitate toward these leaders want to cultivate a little "inner intimidator" of their own. In the author's research, quite a few individuals reported having positive relationships with intimidating leaders. In fact, some described these relationships as profoundly educational and even transformational. So before we throw out all the great intimidators, the author argues, we should stop to consider what

  4. Great Lakes Energy Institute

    Energy Technology Data Exchange (ETDEWEB)

    Alexander, J. Iwan [Case Western Reserve Univ., Cleveland, OH (United States)

    2012-11-18

    The vision of the Great Lakes Energy Institute is to enable the transition to advanced, sustainable energy generation, storage, distribution and utilization through coordinated research, development, and education. The Institute will place emphasis on translating leading edge research into next generation energy technology. The Institute’s research thrusts focus on coordinated research in decentralized power generation devices (e.g. fuel cells, wind turbines, solar photovoltaic devices), management of electrical power transmission and distribution, energy storage, and energy efficiency.

  5. THE GREAT DESCENT CONTINUES

    CERN Document Server

        With precise coordination YE+1 was lowered into the cavern (9-Jan), soon joined by the ?rst barrel wheel YB+2 (19-Jan), then YB+1(4-Feb) and HB+ (13-Feb). The 1920 ton central barrel wheel YB0 rests brie?y on the pit-head cover in anticipation of a monumental descent (28-Feb) that will also trigger an intense campaign of installation of services and detectors underground.  

  6. Skin Barrier Function and Allergens

    DEFF Research Database (Denmark)

    Engebretsen, Kristiane Aasen; Thyssen, Jacob Pontoppidan

    2016-01-01

    The skin is an important barrier protecting us from mechanical insults, microorganisms, chemicals and allergens, but, importantly, also reducing water loss. A common hallmark for many dermatoses is a compromised skin barrier function, and one could suspect an elevated risk of contact sensitization...... and skin barrier status. Psoriasis has traditionally been regarded a Th1-dominated disease, but the discovery of Th17 cells and IL-17 provides new and interesting information regarding the pathogenesis of the disease. Research suggests an inverse relationship between psoriasis and CA, possibly due......) and Th2 (AD) have been proposed as an explanation. Finally, there is convincing evidence that exposure to irritants increases the risk of CS, and patients with ICD are, therefore, at great risk of developing CA. Skin irritation leads to the release of IL-1 and TNF-α, which affects the function of antigen...

  7. Idiopathic great saphenous phlebosclerosis.

    Directory of Open Access Journals (Sweden)

    Ahmadreza Jodati

    2013-06-01

    Full Text Available Arterial sclerosis has been extensively described but reports on venous sclerosis are very sparse. Phlebosclerosis refers to the thickening and hardening of the venous wall. Despite its morphological similarities with arteriosclerosis and potential morbid consequences, phlebosclerosis has gained only little attention. We report a 72 year old male with paralysis and atrophy of the right leg due to childhood poliomyelitis who was referred for coronary artery bypass surgery. The great saphenous vein, harvested from the left leg, showed a hardened cord-like obliterated vein. Surprisingly, harvested veins from the atrophic limb were normal and successfully used for grafting.

  8. Great software debates

    CERN Document Server

    Davis, A

    2004-01-01

    The industry’s most outspoken and insightful critic explains how the software industry REALLY works. In Great Software Debates, Al Davis, shares what he has learned about the difference between the theory and the realities of business and encourages you to question and think about software engineering in ways that will help you succeed where others fail. In short, provocative essays, Davis fearlessly reveals the truth about process improvement, productivity, software quality, metrics, agile development, requirements documentation, modeling, software marketing and sales, empiricism, start-up financing, software research, requirements triage, software estimation, and entrepreneurship.

  9. Making Psychotherapy Great Again?

    Science.gov (United States)

    Plakun, Eric M

    2017-05-01

    Psychotherapy never stopped being as "great" as other treatments. This column explores the evidence base for both psychotherapy and medications, using depression as a specific example. The limitations are comparable for psychotherapy and medication, with much of the evidence based on small degrees of "statistically significant" rather than "clinically meaningful" change. Our field's biomedical emphasis leads to a false assumption that most patients present with single disorders, when comorbidity is the rule rather than the exception. This false assumption contributes to limitations in the evidence base and in our ability to treat patients optimally.

  10. Sprache als Barriere (Language as a Barrier)

    Science.gov (United States)

    Mattheier, Klaus

    1974-01-01

    The concept of language barrier has its derivations in the fields of dialectology, sociology and psychology. In contemporary usage however, the concept has two meanings i.e. regional-cultural barrier and socio-cultural barrier. (Text is in German.) (DS)

  11. Delivery of Biologics Across the Blood-Brain Barrier Through Nanoencapsulation

    DEFF Research Database (Denmark)

    Bruun, Jonas

    is a polymeric micelle made from an anionic triblock copolymer and was intended for delivery of drugs to the central nervous system (CNS), which is protected by the largely impermeable blood-brain barrier (BBB). In order to target the nanocarrier to the brain endothelial cells and obtain receptor...... of the reporter protein. One of the great challenges for drug delivery by nanocarriers is the dilemma of designing a particle that is highly stable whit no cellular interaction while in the blood stream but has a high uptake and efficient drug release in the diseased cells. As a solution to this dilemma...

  12. Great Britain at CERN

    CERN Multimedia

    2006-01-01

    From 14 to 16 November 2006 Administration Building, Bldg. 60/61 - ground and 1st floor 09.30 - 17.30 Fifteen companies will present their latest technologies at the 'Great Britain at CERN' exhibition. British industry will exhibit products and technologies related to the field of particle physics. The main fields represented will be computing technologies, electrical engineering, electronics, mechanical engineering, vacuum & low temperature technologies and particle detectors. The exhibition is organised by BEAMA Exhibitions (the British Electrotechnical and Allied Manufacturers Association). Below you will find: a list of the exhibitors. A detailed programme will be available in due course: from your Departmental secretariat, from the Reception information desk, Building 33, at the exhibition itself. A detailed list of the companies is available at the following FI link: http://fi-dep.web.cern.ch/fi-dep/structure/memberstates/exhibitions_visits.htm LIST OF EXHIBITORS 3D Metrics Almat...

  13. Great Britain at CERN

    CERN Multimedia

    2006-01-01

    From 14 to 16 November 2006 Administration Building, Bldg. 60/61 - ground and 1st floor 09.30 - 17.30 Fifteen companies will present their latest technologies at the 'Great Britain at CERN' exhibition. British industry will exhibit products and technologies related to the field of particle physics. The main fields represented will be computing technologies, electrical engineering, electronics, mechanical engineering, vacuum & low temperature technologies and particle detectors. The exhibition is organised by BEAMA Exhibitions (the British Electrotechnical and Allied Manufacturers Association). Below you will find: a list of the exhibitors. A detailed programme will be available in due course: from your Departmental secretariat, from the Reception information desk, Building 33, at the exhibition itself. A detailed list of the companies is available at the following FI link: http://fi-dep.web.cern.ch/fi-dep/structure/memberstates/exhibitions_visits.htm LIST OF EXHIBITORS 3D Metrics Alma...

  14. A new approach for monitoring ebolavirus in wild great apes.

    Directory of Open Access Journals (Sweden)

    Patricia E Reed

    2014-09-01

    Full Text Available Central Africa is a "hotspot" for emerging infectious diseases (EIDs of global and local importance, and a current outbreak of ebolavirus is affecting multiple countries simultaneously. Ebolavirus is suspected to have caused recent declines in resident great apes. While ebolavirus vaccines have been proposed as an intervention to protect apes, their effectiveness would be improved if we could diagnostically confirm Ebola virus disease (EVD as the cause of die-offs, establish ebolavirus geographical distribution, identify immunologically naïve populations, and determine whether apes survive virus exposure.Here we report the first successful noninvasive detection of antibodies against Ebola virus (EBOV from wild ape feces. Using this method, we have been able to identify gorillas with antibodies to EBOV with an overall prevalence rate reaching 10% on average, demonstrating that EBOV exposure or infection is not uniformly lethal in this species. Furthermore, evidence of antibodies was identified in gorillas thought previously to be unexposed to EBOV (protected from exposure by rivers as topological barriers of transmission.Our new approach will contribute to a strategy to protect apes from future EBOV infections by early detection of increased incidence of exposure, by identifying immunologically naïve at-risk populations as potential targets for vaccination, and by providing a means to track vaccine efficacy if such intervention is deemed appropriate. Finally, since human EVD is linked to contact with infected wildlife carcasses, efforts aimed at identifying great ape outbreaks could have a profound impact on public health in local communities, where EBOV causes case-fatality rates of up to 88%.

  15. Highly calcareous lacustrine soils in the Great Konya Basin, Turkey

    NARCIS (Netherlands)

    Meester, de T.

    1971-01-01

    The Great Konya Basin is in the south of the Central Anatolian Plateau in Turkey. It is a depression without outlet to the sea. The central part of the Basin is the floor of a former Pleistocene lake, the Ancient Konya Lake. This area, called the Lacustrine
    Plain, has highly calcareous

  16. Recent results from TMX-U thermal barrier experiments

    International Nuclear Information System (INIS)

    Molvik, A.W.; Allen, S.; Barter, J.

    1984-01-01

    The Tandem Mirror Experiment-Upgrade (TMX-U) device was designed to study plasma confinement in a tandem mirror with thermal barriers. Previously the author reported improved axial confinement with high end-plug potentials, consistent with thermal barrier operation. Now, the existence of thermal barriers in TMX-U confirmed by measuring the axial potential profile. Specifically, measured the change in energy of a 5-keV deuterium neutral beam that is injected nearly parallel to the axis and is ionized between the barrier and the central cell. The authors found that the barrier potential is lower than the central cell potential, as required for a thermal barrier. The peak potential is at least 2.4 keV, as determined from the minimum energy of end loss ions. In addition, radial transport is reduced by the use of floating and electrodes that map to concentric cylinders in the central cell. Sloshing ions continue to be microstable

  17. Review: The Great Gatsby

    Directory of Open Access Journals (Sweden)

    Antonia de Jesus Sales

    2016-08-01

    Full Text Available A presente resenha busca discutir a tradução de The Great Gatsby para o contexto brasileiro. Diversas traduções foram feitas, em diversas épocas e com repercussão positiva no contexto brasileiro. Para o presente estudo, foi observada a tradução de Vanessa Bárbara, de 2011. Nesse sentido, o aspecto biográficos do autor e a forma como se apresentam os personagens na obra são fatores de cotejamento na obra original e na tradução brasileira. Francis Scott Key Fitzgerald (1896 – 1940 é famoso por ter em suas obras traços biográficos, algo que certamente influencia o leitor que adentra a sua obra. Quanto à recepção de O Grande Gatsby no contexto brasileiro, há que se considerar que O Grande Gatsby teve diversas traduções no Brasil. Depois dessa tradução de Vanessa Bárbara, em 2011, outras três vieram em 2013, juntamente com o filme. Há que considerar os aspectos comerciais embutidos nessas traduções e que muito corroboram para o resultado final. Prova disso são as capas, que são sempre diferenciadas em cada edição lançada. O tradutor nem sempre pode opinar sobre questões como estas. A tradução, a meu ver, é uma obra de qualidade, visto que a tradutora buscou ser fiel, sem dificultar a interpretação da obra para o leitor.

  18. Review: The Great Gatsby

    Directory of Open Access Journals (Sweden)

    Antonia de Jesus Sales

    2016-05-01

    Full Text Available A presente resenha busca discutir a tradução de The Great Gatsby para o contexto brasileiro. Diversas traduções foram feitas, em diversas épocas e com repercussão positiva no contexto brasileiro. Para o presente estudo, foi observada a tradução de Vanessa Bárbara, de 2011. Nesse sentido, o aspecto biográficos do autor e a forma como se apresentam os personagens na obra são fatores de cotejamento na obra original e na tradução brasileira. Francis Scott Key Fitzgerald (1896 – 1940 é famoso por ter em suas obras traços biográficos, algo que certamente influencia o leitor que adentra a sua obra. Quanto à recepção de O Grande Gatsby no contexto brasileiro, há que se considerar que O Grande Gatsby teve diversas traduções no Brasil. Depois dessa tradução de Vanessa Bárbara, em 2011, outras três vieram em 2013, juntamente com o filme. Há que considerar os aspectos comerciais embutidos nessas traduções e que muito corroboram para o resultado final. Prova disso são as capas, que são sempre diferenciadas em cada edição lançada. O tradutor nem sempre pode opinar sobre questões como estas. A tradução, a meu ver, é uma obra de qualidade, visto que a tradutora buscou ser fiel, sem dificultar a interpretação da obra para o leitor.

  19. Great Lakes Environmental Database (GLENDA)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Great Lakes Environmental Database (GLENDA) houses environmental data on a wide variety of constituents in water, biota, sediment, and air in the Great Lakes area.

  20. The Great Plains IDEA Gerontology Program: An Online, Interinstitutional Graduate Degree

    Science.gov (United States)

    Sanders, Gregory F.

    2011-01-01

    The Great-Plains IDEA Gerontology Program is a graduate program developed and implemented by the Great Plains Interactive Distance Education Alliance (Great Plains IDEA). The Great Plains IDEA (Alliance) originated as a consortium of Colleges of Human Sciences ranging across the central United States. This Alliance's accomplishments have included…

  1. Fish tissue contamination in the mid-continental great rivers of the United States

    Science.gov (United States)

    The great rivers of the central United States (Upper Mississippi, Missouri and Ohio rivers) are significant economic and cultural resources, but their ecological condition is not well quantified. The Environmental Monitoring and Assessment Program for Great River Ecosystems (EMAP...

  2. Smart parking barrier

    KAUST Repository

    Alharbi, Abdulrazaq M.

    2016-05-06

    Various methods and systems are provided for smart parking barriers. In one example, among others, a smart parking barrier system includes a movable parking barrier located at one end of a parking space, a barrier drive configured to control positioning of the movable parking barrier, and a parking controller configured to initiate movement of the parking barrier, via the barrier drive. The movable parking barrier can be positioned between a first position that restricts access to the parking space and a second position that allows access to the parking space. The parking controller can initiate movement of the movable parking barrier in response to a positive identification of an individual allowed to use the parking space. The parking controller can identify the individual through, e.g., a RFID tag, a mobile device (e.g., a remote control, smartphone, tablet, etc.), an access card, biometric information, or other appropriate identifier.

  3. Great Palm Island Extension, Density, and Calcification Data for 1872 to 1985

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Extension, Density, and Calcification data from 35 Porites coral cores covering the entire length of the Great Barrier Reef, Australia. Data set contains 35...

  4. Combustion chemical vapor desposited coatings for thermal barrier coating systems

    Energy Technology Data Exchange (ETDEWEB)

    Hampikian, J.M.; Carter, W.B. [Georgia Institute of Technology, Atlanta, GA (United States)

    1995-10-01

    The new deposition process, combustion chemical vapor deposition, shows a great deal of promise in the area of thermal barrier coating systems. This technique produces dense, adherent coatings, and does not require a reaction chamber. Coatings can therefore be applied in the open atmosphere. The process is potentially suitable for producing high quality CVD coatings for use as interlayers between the bond coat and thermal barrier coating, and/or as overlayers, on top of thermal barrier coatings.

  5. Omnidirectional ventilated acoustic barrier

    Science.gov (United States)

    Zhang, Hai-long; Zhu, Yi-fan; Liang, Bin; Yang, Jing; Yang, Jun; Cheng, Jian-chun

    2017-11-01

    As an important problem in acoustics, sound insulation finds applications in a great variety of situations. In the existing schemes, however, there has always been a trade-off between the thinness of sound-insulating devices and their ventilating capabilities, limiting their potentials in the control of low-frequency sound in high ventilation environments. Here, we design and experimentally implement an omnidirectional acoustic barrier with a planar profile, subwavelength thickness ( 0.18 λ ), yet high ventilation. The proposed mechanism is based on the interference between the resonant scattering of discrete states and the background scattering of continuous states which induces a Fano-like asymmetric transmission profile. Benefitting from the binary-structured design of the coiled unit and hollow pipe, it maximally simplifies the design and fabrication while ensuring the ventilation for all the non-resonant units with open tubes. The simulated and measured results agree well, showing the effectiveness of our proposed mechanism to block low frequency sound coming from various directions while allowing 63% of the air flow to pass. We anticipate our design to open routes to design sound insulators and to enable applications in traditionally unattainable cases such as those calling for noise reduction and cooling simultaneously.

  6. The central nervous system

    International Nuclear Information System (INIS)

    Holmes, R.A.

    1984-01-01

    The first section presents a comprehensive evaluation of radionuclide imaging of the central nervous system and provides a comparison of the detection accuracies of radionuclide imaging (RNI) and XCT in certain lesions, realizing that the XCT results may vary when radiocontrast or newer generation XCT scanners are used. Although conventional radionuclide imaging of the central nervous system has experienced no significant changes over the last 7 years except for mild refinements, a new section has been added on positron emission tomography (PET). Most positron radiopharmaceuticals passively cross the intact blood-brain barrier, and their localization has catalyzed renewed interest in our ability to metabolically study and obtain images of the central nervous system. The section on radionuclide cisternography has been rewritten to reflect present day practice and the wider application of XCT in describing conditions affecting the ventricular system

  7. Barrier cell sheath formation

    International Nuclear Information System (INIS)

    Kesner, J.

    1980-04-01

    The solution for electrostatic potential within a simply modeled tandem mirror thermal barrier is seen to exhibit a sheath at each edge of the cell. The formation of the sheath requires ion collisionality and the analysis assmes that the collisional trapping rate into the barrier is considerably slower than the barrier pump rate

  8. You Shall Not Pass – Tight junctions of the Blood Brain Barrier.

    Directory of Open Access Journals (Sweden)

    Hans-Christian eBauer

    2014-12-01

    Full Text Available Tissue barriers restricting the free diffusion of substances between the central nervous system and the systemic circulation are of great medical interest. Excessive leakage of blood-borne molecules into the parenchyma and the concomitant fluctuations in the microenvironment following a transient breakdown of the blood-brain barrier (BBB during ischemic/hypoxic conditions or due to an autoimmune disease are detrimental to the physiology of nervous tissue.On the other hand, the treatment of neurological disorders is often hampered as only minimal amounts of therapeutic agents are able to penetrate a functional BBB or blood cerebrospinal fluid barrier. At the basis of the BBB are, next to an elaborate transporting machinery, intimate cell-cell contacts (tight junctions creating not only a paracellular diffusion constraint but also enabling the vectorial transport across cell monolayers.More recent findings indicate that functional barriers are already established during development, protecting the fetal brain. As an understanding of the biogenesis of TJs might reveal the underlying mechanisms of barrier formation during ontogenic development numerous in vitro systems have been developed to study the assembly and disassembly of TJs. In addition, monitoring the stage-specific expression of TJ proteins during development has brought much insight into the developmental tightening of tissue barriers. Further, over the last two decades a detailed molecular map of tight junctions has emerged.TJs not only represent a cell-cell adhesion structure, but integrate various signaling pathways, thereby directly or indirectly impacting upon processes such as cell proliferation, cytoskeletal rearrangement, and transcriptional control.This review will provide a brief overview on the establishment of the BBB during embryonic development in mammals and a detailed description of the ultrastructure, biogenesis, and molecular composition of epithelial and endothelial

  9. Transposition of the great arteries

    Directory of Open Access Journals (Sweden)

    Castela Eduardo

    2008-10-01

    Full Text Available Abstract Transposition of the great arteries (TGA, also referred to as complete transposition, is a congenital cardiac malformation characterised by atrioventricular concordance and ventriculoarterial (VA discordance. The incidence is estimated at 1 in 3,500–5,000 live births, with a male-to-female ratio 1.5 to 3.2:1. In 50% of cases, the VA discordance is an isolated finding. In 10% of cases, TGA is associated with noncardiac malformations. The association with other cardiac malformations such as ventricular septal defect (VSD and left ventricular outflow tract obstruction is frequent and dictates timing and clinical presentation, which consists of cyanosis with or without congestive heart failure. The onset and severity depend on anatomical and functional variants that influence the degree of mixing between the two circulations. If no obstructive lesions are present and there is a large VSD, cyanosis may go undetected and only be perceived during episodes of crying or agitation. In these cases, signs of congestive heart failure prevail. The exact aetiology remains unknown. Some associated risk factors (gestational diabetes mellitus, maternal exposure to rodenticides and herbicides, maternal use of antiepileptic drugs have been postulated. Mutations in growth differentiation factor-1 gene, the thyroid hormone receptor-associated protein-2 gene and the gene encoding the cryptic protein have been shown implicated in discordant VA connections, but they explain only a small minority of TGA cases. The diagnosis is confirmed by echocardiography, which also provides the morphological details required for future surgical management. Prenatal diagnosis by foetal echocardiography is possible and desirable, as it may improve the early neonatal management and reduce morbidity and mortality. Differential diagnosis includes other causes of central neonatal cyanosis. Palliative treatment with prostaglandin E1 and balloon atrial septostomy are usually

  10. Tandem mirror reactor with thermal barriers

    International Nuclear Information System (INIS)

    Carlson, G.A.; Arfin, B.; Barr, W.L.; Boghosian, B.M.; Erickson, J.L.; Fink, J.H.; Hamilton, G.W.; Logan, B.G.; Myall, J.O.; Neef, W.S. Jr.

    1979-01-01

    This report gives detailed information in the form of the following chapters: (1) overview, (2) plasma physics, (3) magnets, (4) end-plug neutral beams, (5) barrier pump neutral beams, (6) ecr heating, (7) plasma direct converter, and (8) central cell

  11. What Caused the Great Depression?

    Science.gov (United States)

    Caldwell, Jean; O'Driscoll, Timothy G.

    2007-01-01

    Economists and historians have struggled for almost 80 years to account for the American Great Depression, which began in 1929 and lasted until the early years of World War II. In this article, the authors discuss three major schools of thought on the causes of the Great Depression and the long failure of the American economy to return to full…

  12. Barriers to fusion

    International Nuclear Information System (INIS)

    Berriman, A.C.; Butt, R.D.; Dasgupta, M.; Hinde, D.J.; Morton, C.R.; Newton, J.O.

    1999-01-01

    The fusion barrier is formed by the combination of the repulsive Coulomb and attractive nuclear forces. Recent research at the Australian National University has shown that when heavy nuclei collide, instead of a single fusion barrier, there is a set of fusion barriers. These arise due to intrinsic properties of the interacting nuclei such deformation, rotations and vibrations. Thus the range of barrier energies depends on the properties of both nuclei. The transfer of matter between nuclei, forming a neck, can also affect the fusion process. High precision data have been used to determine fusion barrier distributions for many nuclear reactions, leading to new insights into the fusion process

  13. Extremal surface barriers

    International Nuclear Information System (INIS)

    Engelhardt, Netta; Wall, Aron C.

    2014-01-01

    We present a generic condition for Lorentzian manifolds to have a barrier that limits the reach of boundary-anchored extremal surfaces of arbitrary dimension. We show that any surface with nonpositive extrinsic curvature is a barrier, in the sense that extremal surfaces cannot be continuously deformed past it. Furthermore, the outermost barrier surface has nonnegative extrinsic curvature. Under certain conditions, we show that the existence of trapped surfaces implies a barrier, and conversely. In the context of AdS/CFT, these barriers imply that it is impossible to reconstruct the entire bulk using extremal surfaces. We comment on the implications for the firewall controversy

  14. Safety- barrier diagrams

    DEFF Research Database (Denmark)

    Duijm, Nijs Jan

    2008-01-01

    Safety-barrier diagrams and the related so-called 'bow-tie' diagrams have become popular methods in risk analysis. This paper describes the syntax and principles for constructing consistent and valid safety-barrier diagrams. The relation of safety-barrier diagrams to other methods such as fault...... trees and Bayesian networks is discussed. A simple method for quantification of safety-barrier diagrams is proposed. It is concluded that safety-barrier diagrams provide a useful framework for an electronic data structure that integrates information from risk analysis with operational safety management....

  15. Safety-barrier diagrams

    DEFF Research Database (Denmark)

    Duijm, Nijs Jan

    2007-01-01

    Safety-barrier diagrams and the related so-called "bow-tie" diagrams have become popular methods in risk analysis. This paper describes the syntax and principles for constructing consistent and valid safety-barrier diagrams. The relation with other methods such as fault trees and Bayesian networks...... are discussed. A simple method for quantification of safety-barrier diagrams is proposed, including situations where safety barriers depend on shared common elements. It is concluded that safety-barrier diagrams provide a useful framework for an electronic data structure that integrates information from risk...... analysis with operational safety management....

  16. On the evolution of a holocene barrier coast

    DEFF Research Database (Denmark)

    Fruergaard, Mikkel

    in a distinct stratal stacking pattern of each of the investigated coastal barrier systems. We conclude that the overall infilling of the barrier systems over the Holocene was mainly controlled by sea-level rise and sediment supply. However, major storms and tidal channel migration have greatly affected......This thesis investigates the sedimentary evolution of a Holocene barrier coast with special focus on how barrier system stratigraphy is affected by changes in sea-level and sediment supply. Coastal barrier systems comprise about 13% of the world’s coastlines and they are mportant components...... of the stratigraphic record of the Earth. Sea-level rise and sediment supply are the two most important factors controlling barrier system evolution. Detailed depositional reconstructions of a number of barrier systems from the Danish Wadden Sea area have been carried out in order to evaluate the sedimentary effects...

  17. Cosmic Reason of Great Glaciation

    Science.gov (United States)

    Bagrov, Alexander; Murtazov, Andrey

    The origin of long-time and global glaciations in the past of our planet, which have been named «great», is still not clear. Both the advance of glaciers and their subsequent melting must be connected with some energy consuming processes. There is a powerful energy source permanently functioning throughout the Earth’s history - the solar radiation. The equality of the incoming shortwave solar energy and the transformed long-wave energy emitted by the Earth provides for the whole ecosphere’s sustainable evolution. Great glaciations might be caused by space body falls into the world oceans. If the body is large enough, it can stir waters down to the bottom. The world waters are part of the global heat transfer from the planet’s equator to its poles (nowadays, mostly to the North Pole). The mixing of the bottom and surface waters breaks the circulation of flows and they stop. The termination of heat transfer to the poles will result in an icecap at high latitudes which in its turn will decrease the total solar heat inflow to the planet and shift the pole ice boarder to the equator. This positive feedback may last long and result in long-time glaciations. The oceanic currents will remain only near the equator. The factor obstructing the global cooling is the greenhouse effect. Volcanic eruptions supply a lot of carbon dioxide into the atmosphere. When due to the increased albedo the planet receives less solar heat, plants bind less carbon oxide into biomass and more of it retains in the atmosphere. Therefore, the outflow of heat from the planet decreases and glaciations does not involve the whole planet. The balance established between the heat inflow and heat losses is unstable. Any imbalance acts as a positive feed-back factor. If the volcanic activity grows, the inflow of the carbon dioxide into the atmosphere will cause its heating-up (plants will fail to reproduce themselves quickly enough to utilize the carbonic acid). The temperature growth will lead to

  18. Woody encroachment in northern Great Plains grasslands: Perceptions, actions, and needs

    Science.gov (United States)

    Symstad, Amy J.; Leis, Sherry A.

    2017-01-01

    The United States Northern Great Plains (NGP) has a high potential for landscape-scale conservation, but this grassland landscape is threatened by encroachment of woody species. We surveyed NGP land managers to identify patterns in, and illustrate a broad range of, individual managers' perceptions on (1) the threat of woody encroachment to grasslands they manage, and (2) what management practices they use that may influence woody encroachment in this region. In the 34 surveys returned, which came from predominantly public lands in the study area, 79% of responses reported moderate or substantial woody encroachment. Eastern redcedar (Juniperus virginiana) and Rocky Mountain juniper (Juniperus scopulorum) were the most problematic encroachers. Thirty-one survey respondents said that prescribed fire was used on the lands they manage, and 64% of these responses reported that controlling woody encroachment was a fire management objective. However, only 18% of survey respondents using prescribed fire were achieving their desired fire return interval. Most respondents reported using mechanical and/or chemical methods to control woody species. In contrast to evidence from the central and southern Great Plains, few survey respondents viewed grazing as affecting encroachment. Although the NGP public land managers we surveyed clearly recognize woody encroachment as a problem and are taking steps to address it, many feel that the rate of their management is not keeping pace with the rate of encroachment. Developing strategies for effective woody plant control in a variety of NGP management contexts requires filling ecological science gaps and overcoming societal barriers to using prescribed fire.

  19. Gliovascular and cytokine interactions modulate brain endothelial barrier in vitro.

    Science.gov (United States)

    Chaitanya, Ganta V; Cromer, Walter E; Wells, Shannon R; Jennings, Merilyn H; Couraud, P Olivier; Romero, Ignacio A; Weksler, Babette; Erdreich-Epstein, Anat; Mathis, J Michael; Minagar, Alireza; Alexander, J Steven

    2011-11-23

    The glio-vascular unit (G-unit) plays a prominent role in maintaining homeostasis of the blood-brain barrier (BBB) and disturbances in cells forming this unit may seriously dysregulate BBB. The direct and indirect effects of cytokines on cellular components of the BBB are not yet unclear. The present study compares the effects of cytokines and cytokine-treated astrocytes on brain endothelial barrier. 3-dimensional transwell co-cultures of brain endothelium and related-barrier forming cells with astrocytes were used to investigate gliovascular barrier responses to cytokines during pathological stresses. Gliovascular barrier was measured using trans-endothelial electrical resistance (TEER), a sensitive index of in vitro barrier integrity. We found that neither TNF-α, IL-1β or IFN-γ directly reduced barrier in human or mouse brain endothelial cells or ECV-304 barrier (independent of cell viability/metabolism), but found that astrocyte exposure to cytokines in co-culture significantly reduced endothelial (and ECV-304) barrier. These results indicate that the barrier established by human and mouse brain endothelial cells (and other cells) may respond positively to cytokines alone, but that during pathological conditions, cytokines dysregulate the barrier forming cells indirectly through astrocyte activation involving reorganization of junctions, matrix, focal adhesion or release of barrier modulating factors (e.g. oxidants, MMPs). © 2011 Chaitanya et al; licensee BioMed Central Ltd.

  20. Permeable reactive barriers for pollutant removal from groundwater

    International Nuclear Information System (INIS)

    Simon, F.G.; Meggyes, T.

    2001-01-01

    The removal of pollutants from the groundwater using permeable reactive barriers is a novel in-situ groundwater remediation technology. The most relevant decontamination processes used are chemical reduction, oxidation, precipitation and sorption, for which examples are given. Some common organic pollutants are halogenated hydrocarbons, aromatic and nitroaromatic compounds which can be treated in reactive barriers successfully. Lead, chromium and, in particular, uranium are dealt with in great detail among inorganic pollutants because of their occurrence in many European countries. Construction methods for cut-off walls and reactive barriers exhibit similar features. Apart from conventional methods, drilling, deep soil mixing, jet technology, arrays of wells, injected systems and biobarriers are applied to construct permeable reactive barriers. Permeable reactive barriers bear great potential for the future in remediation engineering. (orig.)

  1. Great Lakes Environmental Research Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — NOAA-GLERL and its partners conduct innovative research on the dynamic environments and ecosystems of the Great Lakes and coastal regions to provide information for...

  2. What Caused the Great Recession?

    OpenAIRE

    Homburg, Stefan

    2014-01-01

    This paper examines five possible explanations for the Great Recession of 2008 and 2009, using data for the United States and the eurozone. Of these five hypotheses, four are not supported by the data, while the fifth appears reasonable.

  3. Arthroscopy of the great toe

    NARCIS (Netherlands)

    Frey, C.; van Dijk, C. N.

    1999-01-01

    The few available reports of arthroscopic treatment of the first MTP joint in the literature indicate favorable outcome. However, arthroscopy of the great toe is an advanced technique and should only be undertaken by experienced surgeons

  4. The Sixth Great Mass Extinction

    Science.gov (United States)

    Wagler, Ron

    2012-01-01

    Five past great mass extinctions have occurred during Earth's history. Humanity is currently in the midst of a sixth, human-induced great mass extinction of plant and animal life (e.g., Alroy 2008; Jackson 2008; Lewis 2006; McDaniel and Borton 2002; Rockstrom et al. 2009; Rohr et al. 2008; Steffen, Crutzen, and McNeill 2007; Thomas et al. 2004;…

  5. Multilayer moisture barrier

    Science.gov (United States)

    Pankow, Joel W; Jorgensen, Gary J; Terwilliger, Kent M; Glick, Stephen H; Isomaki, Nora; Harkonen, Kari; Turkulainen, Tommy

    2015-04-21

    A moisture barrier, device or product having a moisture barrier or a method of fabricating a moisture barrier having at least a polymer layer, and interfacial layer, and a barrier layer. The polymer layer may be fabricated from any suitable polymer including, but not limited to, fluoropolymers such as polyethylene terephthalate (PET) or polyethylene naphthalate (PEN), or ethylene-tetrafluoroethylene (ETFE). The interfacial layer may be formed by atomic layer deposition (ALD). In embodiments featuring an ALD interfacial layer, the deposited interfacial substance may be, but is not limited to, Al.sub.2O.sub.3, AlSiO.sub.x, TiO.sub.2, and an Al.sub.2O.sub.3/TiO.sub.2 laminate. The barrier layer associated with the interfacial layer may be deposited by plasma enhanced chemical vapor deposition (PECVD). The barrier layer may be a SiO.sub.xN.sub.y film.

  6. Barrier penetration database

    International Nuclear Information System (INIS)

    Fainberg, A.; Bieber, A.M. Jr.

    1978-11-01

    This document is intended to supply the NRC and nuclear power plant licensees with basic data on the times required to penetrate forcibly the types of barriers commonly found in nuclear plants. These times are necessary for design and evaluation of the physical protection system required under 10CFR73.55. Each barrier listed is described in detail. Minor variations in basic barrier construction that result in the same penetration time, are also described

  7. Transport barriers in plasmas

    International Nuclear Information System (INIS)

    Caldas, I L; Szezech, J D Jr; Kroetz, T; Marcus, F A; Roberto, M; Viana, R L; Lopes, S R

    2012-01-01

    We discuss the creation of transport barriers in magnetically confined plasmas with non monotonic equilibrium radial profiles. These barriers reduce the transport in the shearless region (i.e., where the twist condition does not hold). For the chaotic motion of particles in an equilibrium electric field with a nonmonotonic radial profile, perturbed by electrostatic waves, we show that a nontwist transport barrier can be created in the plasma by modifying the electric field radial profile. We also show non twist barriers in chaotic magnetic field line transport in the plasma near to the tokamak wall with resonant modes due to electric currents in external coils.

  8. Precipitation Dynamical Downscaling Over the Great Plains

    Science.gov (United States)

    Hu, Xiao-Ming; Xue, Ming; McPherson, Renee A.; Martin, Elinor; Rosendahl, Derek H.; Qiao, Lei

    2018-02-01

    Detailed, regional climate projections, particularly for precipitation, are critical for many applications. Accurate precipitation downscaling in the United States Great Plains remains a great challenge for most Regional Climate Models, particularly for warm months. Most previous dynamic downscaling simulations significantly underestimate warm-season precipitation in the region. This study aims to achieve a better precipitation downscaling in the Great Plains with the Weather Research and Forecast (WRF) model. To this end, WRF simulations with different physics schemes and nudging strategies are first conducted for a representative warm season. Results show that different cumulus schemes lead to more pronounced difference in simulated precipitation than other tested physics schemes. Simply choosing different physics schemes is not enough to alleviate the dry bias over the southern Great Plains, which is related to an anticyclonic circulation anomaly over the central and western parts of continental U.S. in the simulations. Spectral nudging emerges as an effective solution for alleviating the precipitation bias. Spectral nudging ensures that large and synoptic-scale circulations are faithfully reproduced while still allowing WRF to develop small-scale dynamics, thus effectively suppressing the large-scale circulation anomaly in the downscaling. As a result, a better precipitation downscaling is achieved. With the carefully validated configurations, WRF downscaling is conducted for 1980-2015. The downscaling captures well the spatial distribution of monthly climatology precipitation and the monthly/yearly variability, showing improvement over at least two previously published precipitation downscaling studies. With the improved precipitation downscaling, a better hydrological simulation over the trans-state Oologah watershed is also achieved.

  9. Questioning the role of actinfree Gc-Globulin as actin scavenger in neurodegenerative central nervous system disease: relationship to S-100B levels and blood-brain barrier function.

    Science.gov (United States)

    Gressner, Olav A; Schifflers, Marie-Claire; Kim, Philipp; Heuts, Leo; Lahme, Birgit; Gressner, Axel M

    2009-02-01

    Preliminary studies report on significantly higher levels of the major cytoskeleton protein actin in CSF of patients with neurodegenerative conditions and that the dynamics of these levels obviously correlates with disease progression and clinical disability. One of the primary functions of actinfree Gc-Globulin is to bind and neutralize extracellular monomeric actin, released into the circulation by necrotic or ruptured cells, and thus ameliorating the clinical outcome in situations of severe organ damage. This is the first study to investigate actinfree Gc-Globulin and S100-B levels (as reliable marker of neurodegeneration) in paired CSF and serum samples of patients with multietiological CNS diseases. 42% of all patients with CNS disease displayed serum concentrations of actinfree Gc-Globulin above the established reference range. CSF concentrations of actinfree Gc-Globulin and S100-B were positively correlated with the severity of blood-brain barrier (BBB) dysfunction. Furthermore, patients with severe BBB dysfunction presented a higher percentage of intrathecal synthesis of actinfree Gc-Globulin compared to patients with mild to moderate dysfunction and to patients with normal BBB function. Representative longitudinal data from selected patients demonstrated an inverse behaviour of actinfree Gc-Globulin and S100-B CSF concentrations, suggesting a consumption of the actin scavenger capacity of Gc-Globulin in times of increased neuronal damage. This presumption was supported by the fact that those conditions associated with a severe neuronal damage, in particular CNS trauma, and highest S100-B concentrations simultaneously displayed lowest actinfree Gc-Globulin levels, and thus residual actin binding capacity of Gc-Globulin. In summary, our data propose a function of actinfree Gc-Globulin also in the clearance of actin filaments from CSF of patients with neuronal damage. However, active recruitment of hepatic derived actinfree Gc-Globulin to the site of CNS

  10. A novel transgenic zebrafish model for blood-brain and blood-retinal barrier development

    Directory of Open Access Journals (Sweden)

    Sugimoto Masahiko

    2010-07-01

    Full Text Available Abstract Background Development and maintenance of the blood-brain and blood-retinal barrier is critical for the homeostasis of brain and retinal tissue. Despite decades of research our knowledge of the formation and maintenance of the blood-brain (BBB and blood-retinal (BRB barrier is very limited. We have established an in vivo model to study the development and maintenance of these barriers by generating a transgenic zebrafish line that expresses a vitamin D-binding protein fused with enhanced green fluorescent protein (DBP-EGFP in blood plasma, as an endogenous tracer. Results The temporal establishment of the BBB and BRB was examined using this transgenic line and the results were compared with that obtained by injection of fluorescent dyes into the sinus venosus of embryos at various stages of development. We also examined the expression of claudin-5, a component of tight junctions during the first 4 days of development. We observed that the BBB of zebrafish starts to develop by 3 dpf, with expression of claudin-5 in the central arteries preceding it at 2 dpf. The hyaloid vasculature in the zebrafish retina develops a barrier function at 3 dpf, which endows the zebrafish with unique advantages for studying the BRB. Conclusion Zebrafish embryos develop BBB and BRB function simultaneously by 3 dpf, which is regulated by tight junction proteins. The Tg(l-fabp:DBP-EGFP zebrafish will have great advantages in studying development and maintenance of the blood-neural barrier, which is a new application for the widely used vertebrate model.

  11. Converse Barrier Certificate Theorems

    DEFF Research Database (Denmark)

    Wisniewski, Rafael; Sloth, Christoffer

    2016-01-01

    This paper shows that a barrier certificate exists for any safe dynamical system. Specifically, we prove converse barrier certificate theorems for a class of structurally stable dynamical systems. Other authors have developed a related result by assuming that the dynamical system has neither...

  12. Famous puzzles of great mathematicians

    CERN Document Server

    Petković, Miodrag S

    2009-01-01

    This entertaining book presents a collection of 180 famous mathematical puzzles and intriguing elementary problems that great mathematicians have posed, discussed, and/or solved. The selected problems do not require advanced mathematics, making this book accessible to a variety of readers. Mathematical recreations offer a rich playground for both amateur and professional mathematicians. Believing that creative stimuli and aesthetic considerations are closely related, great mathematicians from ancient times to the present have always taken an interest in puzzles and diversions. The goal of this

  13. Skin barrier function

    DEFF Research Database (Denmark)

    2016-01-01

    Renowned experts present the latest knowledge Although a very fragile structure, the skin barrier is probably one of the most important organs of the body. Inward/out it is responsible for body integrity and outward/in for keeping microbes, chemicals, and allergens from penetrating the skin. Since...... the role of barrier integrity in atopic dermatitis and the relationship to filaggrin mutations was discovered a decade ago, research focus has been on the skin barrier, and numerous new publications have become available. This book is an interdisciplinary update offering a wide range of information...... on the subject. It covers new basic research on skin markers, including results on filaggrin and on methods for the assessment of the barrier function. Biological variation and aspects of skin barrier function restoration are discussed as well. Further sections are dedicated to clinical implications of skin...

  14. Barriers to the future

    Energy Technology Data Exchange (ETDEWEB)

    Massey, C T

    1986-09-01

    Opportunities for the British coal industry seem vast yet there are still barriers to progress. Seven areas are identified and discussed: mining mobility (for example, longwall mining systems are rigid and inflexible compared with American stall and pillar working); mine structure (many mines are more suitable to pit ponies than to large pieces of equipment); financial barriers (Government requires the industry to break even in 1987/88); personnel barriers (less specialization, better use of skills); safety barriers (increased use of remote control, ergonomics and robotics to protect workers); microelectronic management (nationalization has cushioned management from the market place; there is a need for a more multidisciplinary approach to the industry); and legal barriers (most legislation in the past has been in response to accidents; legislation external to the industry but affecting it is more fundamental).

  15. Making a Great First Impression

    Science.gov (United States)

    Evenson, Renee

    2007-01-01

    Managers and business owners often base hiring decisions on first impressions. That is why it is so important to teach students to make a great first impression--before they go on that first job interview. Managers do not have unrealistic expectations, they just want to hire people who they believe can develop into valuable employees. A nice…

  16. Great Basin paleoenvironmental studies project

    International Nuclear Information System (INIS)

    1993-01-01

    Project goals, project tasks, progress on tasks, and problems encountered are described and discussed for each of the studies that make up the Great Basin Paleoenvironmental Studies Project for Yucca Mountain. These studies are: Paleobotany, Paleofauna, Geomorphology, and Transportation. Budget summaries are also given for each of the studies and for the overall project

  17. The Great Books and Economics.

    Science.gov (United States)

    Hartley, James E.

    2001-01-01

    Describes an introductory economics course in which all of the reading material is drawn from the Great Books of Western Civilization. Explains the rationale and mechanics of the course. Includes an annotated course syllabus that details how the reading material relates to the lecture material. (RLH)

  18. Great tit hatchling sex ratios

    NARCIS (Netherlands)

    Lessells, C.M.; Mateman, A.C.; Visser, J.

    1996-01-01

    The sex of Great Tit Parus major nestlings was determined using PCR RAPDs. Because this technique requires minute amounts of DNA, chicks could be sampled soon (0-2d) after hatching, before any nestling mortality occurred. The proportion of males among 752 chicks hatching in 102 broods (98.9% of

  19. The Great Gatsby. [Lesson Plan].

    Science.gov (United States)

    Zelasko, Ken

    Based on F. Scott Fitzgerald's novel "The Great Gatsby," this lesson plan presents activities designed to help students understand that adapting part of a novel into a dramatic reading makes students more intimate with the author's intentions and craft; and that a part of a novel may lend itself to various oral interpretations. The main activity…

  20. Great Basin wildlife disease concerns

    Science.gov (United States)

    Russ Mason

    2008-01-01

    In the Great Basin, wildlife diseases have always represented a significant challenge to wildlife managers, agricultural production, and human health and safety. One of the first priorities of the U.S. Department of Agriculture, Division of Fish and Wildlife Services was Congressionally directed action to eradicate vectors for zoonotic disease, particularly rabies, in...

  1. Great Lakes Regional Biomass Energy Program

    International Nuclear Information System (INIS)

    Kuzel, F.

    1993-01-01

    The Great Lakes Regional Biomass Energy Program (GLRBEP) was initiated September, 1983, with a grant from the Office of Energy Efficiency and Renewable Energy of the US Department of Energy (DOE). The program provides resources to public and private organizations in the Great Lakes region to increase the utilization and production of biomass fuels. The objectives of the GLRBEP are to: (1) improve the capabilities and effectiveness of biomass energy programs in the state energy offices; (2) assess the availability of biomass resources for energy in light of other competing needs and uses; (3) encourage private sector investments in biomass energy technologies; (4) transfer the results of government-sponsored biomass research and development to the private sector; (5) eliminate or reduce barriers to private sector use of biomass fuels and technology; (6) prevent or substantially mitigate adverse environmental impacts of biomass energy use. The Program Director is responsible for the day-to-day activities of the GLRBEP and for implementing program mandates. A 40 member Technical Advisory Committee (TAC) sets priorities and recommends projects. The governor of each state in the region appoints a member to the Steering Council, which acts on recommendations of the TAC and sets basic program guidelines. The GLRBEP is divided into three separate operational elements. The State Grants component provides funds and direction to the seven state energy offices in the region to increase their capabilities in biomass energy. State-specific activities and interagency programs are emphasized. The Subcontractor component involves the issuance of solicitations to undertake projects that address regional needs, identified by the Technical Advisory Committee. The Technology Transfer component includes the development of nontechnical biomass energy publications and reports by Council staff and contractors, and the dissemination of information at conferences, workshops and other events

  2. Transport of drugs across the blood-brain barrier by nanoparticles.

    Science.gov (United States)

    Wohlfart, Stefanie; Gelperina, Svetlana; Kreuter, Jörg

    2012-07-20

    The central nervous system is well protected by the blood-brain barrier (BBB) which maintains its homeostasis. Due to this barrier many potential drugs for the treatment of diseases of the central nervous system (CNS) cannot reach the brain in sufficient concentrations. One possibility to deliver drugs to the CNS is the employment of polymeric nanoparticles. The ability of these carriers to overcome the BBB and to produce biologic effects on the CNS was shown in a number of studies. Over the past few years, progress in understanding of the mechanism of the nanoparticle uptake into the brain was made. This mechanism appears to be receptor-mediated endocytosis in brain capillary endothelial cells. Modification of the nanoparticle surface with covalently attached targeting ligands or by coating with certain surfactants enabling the adsorption of specific plasma proteins are necessary for this receptor-mediated uptake. The delivery of drugs, which usually are not able to cross the BBB, into the brain was confirmed by the biodistribution studies and pharmacological assays in rodents. Furthermore, the presence of nanoparticles in the brain parenchyma was visualized by electron microscopy. The intravenously administered biodegradable polymeric nanoparticles loaded with doxorubicin were successfully used for the treatment of experimental glioblastoma. These data, together with the possibility to employ nanoparticles for delivery of proteins and other macromolecules across the BBB, suggest that this technology holds great promise for non-invasive therapy of the CNS diseases. Copyright © 2011 Elsevier B.V. All rights reserved.

  3. 'We can't get anything done because...': making sense of 'barriers' to Practice-based Commissioning.

    Science.gov (United States)

    Checkland, Kath; Coleman, Anna; Harrison, Stephen; Hiroeh, Urara

    2009-01-01

    To investigate the issues raised by participants as 'barriers' to the development of Practice-based Commissioning (PBC) in 'early adopter' sites in England. Detailed case studies of five PBC consortia in three Primary Care Trusts (PCTs). Data collection included interviews with a wide range of respondents (46 in total), including general practitioners, PCT employees, Local Authority employees and patient representatives, observation of many different types of meetings (68 in total), and analysis of documents tabled at meetings and circulated at other times. It has been claimed that progress in developing PBC has been slow. Our respondents articulated a number of factors that they felt were holding them back, which could have been identified as 'barriers' preventing change. The issues raised were consistent across our sites (lack of time, resources and personnel, and difficult relationships with the PCT), but observation suggested that these issues arose out of very different organizational 'sensemaking', and as a result the apparent 'barriers' had different meanings in different organizational contexts. Weick's concept of 'organizational sensemaking' provides a useful framework within which to explore the problems encountered when implementing policy. Observational methods are a powerful tool in understanding sensemaking. The variations in sensemaking that we observed suggest that the use of 'barrier' metaphors in descriptions of implementation problems risks homogenizing the portrayal of situations that differ greatly in reality. This implies that top-down or centrally driven solutions to such situations will often be inappropriate.

  4. Compositional Safety Analysis using Barrier Certificates

    DEFF Research Database (Denmark)

    Sloth, Christoffer; Pappas, George J.; Wisniewski, Rafael

    2012-01-01

    This paper proposes a compositional method for verifying the safety of a dynamical system, given as an interconnection of subsystems. The safety verification is conducted by the use of the barrier certificate method; hence, the contribution of this paper is to show how to obtain compositional...... conditions for safety verification. We show how to formulate the verification problem, as a composition of coupled subproblems, each given for one subsystem. Furthermore, we show how to find the compositional barrier certificates via linear and sum of squares programming problems. The proposed method makes...... it possible to verify the safety of higher dimensional systems, than the method for centrally computed barrier certificates. This is demonstrated by verifying the safety of an emergency shutdown of a wind turbine....

  5. Vehicle barrier systems

    International Nuclear Information System (INIS)

    Sena, P.A.

    1986-01-01

    The ground vehicle is one of the most effective tools available to an adversary force. Vehicles can be used to penetrate many types of perimeter barriers, transport equipment and personnel rapidly over long distances, and deliver large amounts of explosives directly to facilities in suicide missions. The function of a vehicle barrier system is to detain or disable a defined threat vehicle at a selected distance from a protected facility. Numerous facilities are installing, or planning to install, vehicle barrier systems and many of these facilities are requesting guidance to do so adequately. Therefore, vehicle barriers are being evaluated to determine their stopping capabilities so that systems can be designed that are both balanced and capable of providing a desired degree of protection. Equally important, many of the considerations that should be taken into account when establishing a vehicle barrier system have been identified. These considerations which pertain to site preparation, barrier selection, system integration and operation, and vehicle/barrier interaction, are discussed in this paper

  6. Converse Barrier Certificate Theorem

    DEFF Research Database (Denmark)

    Wisniewski, Rafael; Sloth, Christoffer

    2013-01-01

    This paper presents a converse barrier certificate theorem for a generic dynamical system.We show that a barrier certificate exists for any safe dynamical system defined on a compact manifold. Other authors have developed a related result, by assuming that the dynamical system has no singular...... points in the considered subset of the state space. In this paper, we redefine the standard notion of safety to comply with generic dynamical systems with multiple singularities. Afterwards, we prove the converse barrier certificate theorem and illustrate the differences between ours and previous work...

  7. The Blood-Brain Barrier: An Engineering Perspective

    Directory of Open Access Journals (Sweden)

    Andrew eWong

    2013-08-01

    Full Text Available It has been more than 100 years since Paul Ehrlich reported that various water-soluble dyes injected into the circulation did not enter the brain. Since Ehrlich’s first experiments, only a small number of molecules, such as alcohol and caffeine have been found to cross the blood-brain barrier, and it remains the major roadblock to treatment of many central nervous system diseases. At the same time, many central nervous system diseases are associated with disruption of the blood-brain barrier that can lead to changes in permeability, modulation of immune cell transport, and trafficking of pathogens into the brain. Therefore advances in our understanding of the structure and function of the blood-brain barrier are key to advances in treatment of a wide range of central nervous system diseases. Over the past 10 years it has become recognized that the blood-brain barrier is a complex dynamic system that involves biomechanical and biochemical signaling between the vascular system and the brain. Here we reconstruct the structure, function, and transport properties of the blood-brain barrier from an engineering perspective. New insight into the physics of the blood-brain barrier could ultimately lead to clinical advances in the treatment of central nervous system diseases.

  8. Southern Great Plains Safety Orientation

    Energy Technology Data Exchange (ETDEWEB)

    Schatz, John

    2014-05-01

    Welcome to the Atmospheric Radiation Measurement (ARM) Climate Research Facility (ARM) Southern Great Plains (SGP) site. This U.S. Department of Energy (DOE) site is managed by Argonne National Laboratory (ANL). It is very important that all visitors comply with all DOE and ANL safety requirements, as well as those of the Occupational Safety and Health Administration (OSHA), the National Fire Protection Association, and the U.S. Environmental Protection Agency, and with other requirements as applicable.

  9. Information barriers and authentication

    International Nuclear Information System (INIS)

    MacArthur, D.W.; Wolford, J.K.

    2001-01-01

    Acceptance of nuclear materials into a monitoring regime is complicated if the materials are in classified shapes or have classified composition. An attribute measurement system with an information barrier can be emplo,yed to generate an unclassified display from classified measurements. This information barrier must meet two criteria: (1) classified information cannot be released to the monitoring party, and (2) the monitoring party must be convinced that the unclassified output accurately represents the classified input. Criterion 1 is critical to the host country to protect the classified information. Criterion 2 is critical to the monitoring party and is often termed the 'authentication problem.' Thus, the necessity for authentication of a measurement system with an information barrier stems directly from the description of a useful information barrier. Authentication issues must be continually addressed during the entire development lifecycle of the measurement system as opposed to being applied only after the system is built.

  10. Barrier Infrared Detector (BIRD)

    Data.gov (United States)

    National Aeronautics and Space Administration — A recent breakthrough in MWIR detector design, has resulted in a high operating temperature (HOT) barrier infrared detector (BIRD) that is capable of spectral...

  11. Protective barrier development: Overview

    International Nuclear Information System (INIS)

    Wing, N.R.; Gee, G.W.

    1990-01-01

    Protective barrier and warning marker systems are being developed to isolate wastes disposed of near the earth's surface at the Hanford Site. The barrier is designed to function in an arid to semiarid climate, to limit infiltration and percolation of water through the waste zone to near-zero, to be maintenance free, and to last up to 10,000 yr. Natural materials (e.g., fine soil, sand, gravel, riprap, clay, asphalt) have been selected to optimize barrier performance and longevity and to create an integrated structure with redundant features. These materials isolate wastes by limiting water drainage; reducing the likelihood of plant, animal, and human intrusion; controlling emission of noxious gases; and minimizing erosion. Westinghouse Hanford Company and Pacific Northwest Laboratory efforts to assess the performance of various barrier and marker designs will be discussed

  12. Engineered barriers: current status

    International Nuclear Information System (INIS)

    Atkinson, A.; Marsh, G.P.

    1988-01-01

    This report summarises the current state of research relevant to assessing the performance of engineered barriers made of steel and concrete in radioactive waste repositories. The objective of these barriers is to contain the radionuclides within them by providing both physical and chemical impediment to their release. The physical barriers are of most value for highly soluble isotopes with relatively short half-lives (eg 137 Cs), since they can provide containment until a large fraction of the activity has decayed. In addition they can facilitate retrievability for some period after disposal. The chemical barriers operate by beneficial conditioning of the near field groundwater and providing sites for sorption of radionuclides. Both of these reduce the aqueous concentration of radionuclides in the near field. (author)

  13. Skin barrier composition

    International Nuclear Information System (INIS)

    Osburn, F.G.

    1985-01-01

    A skin barrier composition comprises a mixture of a copolymer resin of ethylene and vinyl acetate (EVA), and a water-insoluble dry tack-providing elastomer such as polyisobutylene. The composition after mixing and molding, is subjected to ionizing irradiation to form cross-linked polymer networks of the EVA. The compositions have exceptional properties for use as barrier sheets, rings, or strips in ostomy, wound drainage, and incontinence devices. (author)

  14. Skin barrier composition

    Energy Technology Data Exchange (ETDEWEB)

    Osburn, F G

    1985-06-12

    A skin barrier composition comprises a mixture of a copolymer resin of ethylene and vinyl acetate (EVA), and a water-insoluble dry tack-providing elastomer such as polyisobutylene. The composition after mixing and molding, is subjected to ionizing irradiation to form cross-linked polymer networks of the EVA. The compositions have exceptional properties for use as barrier sheets, rings, or strips in ostomy, wound drainage, and incontinence devices.

  15. TMX-U thermal-barrier experiments

    International Nuclear Information System (INIS)

    Simonen, T.C.; Allen, S.L.; Barter, J.D.

    1988-01-01

    This review of thermal-barrier experiments in the Tandem Mirror Experiment Upgrade (TMX-U) describes our progress at Lawrence Livermore National Laboratory in plasma confinement and central-cell heating. Thermal barriers in TMX-U improved axial confinement by two orders of magnitude over a limited range of densities, compared with confinement in single-cell mirrors at the same ion temperature. Our study shows that central-cell radial nonambipolar confinement scales as neoclassical theory and can be eliminated by floating the end walls. Radial ambipolar losses can also be measured and reduced. The electron energy balance is improved in tandem mirrors to near classical, resulting in T/sub e/ up to 0.28 keV. Electron cyclotron heating (ECH) efficiencies up to 42 percent, with low levels of electron microinstability, were achieved when hot electrons in the thermal barrier were heated to average betas as large as 15 percent. The hot-electron distribution is measured from X rays and is modeled by a Fokker-Planck code that includes heating from cavity radio-frequency (RF) fields. Neutral-beam injection in the central cell created average ion betas up to 5 percent with radial profiles of hot ions that are modeled accurately by a radial Fokker-Planck code. Gas fueling between two fundamental ion cyclotron heating (ICH) resonances resulted in symmetrical heating of passing ions toward both ends

  16. Central index of dose information

    International Nuclear Information System (INIS)

    1991-01-01

    The Central Index of Dose Information (CIDI) is a national database of occupational exposure to radiation operated by the NRPB as agent for the Health and Safety Executive. It receives summarised information on the radiation doses to classified persons in Great Britain annually from Approved Dosimetry Services. This document is the first annual CIDI summary of the data, giving statistics for 1986. (UK)

  17. Considering the potential effect of faulting on regional-scale groundwater flow: an illustrative example from Australia's Great Artesian Basin

    Science.gov (United States)

    Smerdon, Brian D.; Turnadge, Chris

    2015-08-01

    Hydraulic head measurements in the Great Artesian Basin (GAB), Australia, began in the early 20th century, and despite subsequent decades of data collection, a well-accepted smoothed potentiometric surface has continually assumed a contiguous aquifer system. Numerical modeling was used to produce alternative potentiometric surfaces for the Cadna-owie-Hooray aquifers with and without the effect of major faults. Where a fault created a vertical offset between the aquifers and was juxtaposed with an aquitard, it was assumed to act as a lateral barrier to flow. Results demonstrate notable differences in the central portion of the study area between potentiometric surfaces including faults and those without faults. Explicitly considering faults results in a 25-50 m difference where faults are perpendicular to the regional flow path, compared to disregarding faults. These potential barriers create semi-isolated compartments where lateral groundwater flow may be diminished or absent. Groundwater management in the GAB relies on maintaining certain hydraulic head conditions and, hence, a potentiometric surface. The presence of faulting has two implications for management: (1) a change in the inferred hydraulic heads (and associated fluxes) at the boundaries of regulatory jurisdictions; and (2) assessment of large-scale extractions occurring at different locations within the GAB.

  18. Learning and the Great Moderation

    OpenAIRE

    Bullard, James B.; Singh, Aarti

    2009-01-01

    We study a stylized theory of the volatility reduction in the U.S. after 1984 - the Great Moderation - which attributes part of the stabilization to less volatile shocks and another part to more difficult inference on the part of Bayesian households attempting to learn the latent state of the economy. We use a standard equilibrium business cycle model with technology following an unobserved regime-switching process. After 1984, according to Kim and Nelson (1999a), the variance of U.S. macroec...

  19. Pricing regulations in Great Britain

    International Nuclear Information System (INIS)

    Cicoletti, G.

    1993-01-01

    This paper briefly describes the structure and functions of Great Britain's essential electric power regulatory authority institutionalized by the 1989 British Electricity Act, i.e., the Office of Electricity Regulation, OFFER, and the responsibilities and tasks of the head of OFFER -the Director General of Electricity Supply (DGES). In particular, with regard to the latter, the paper describes how the DGES works together with regional electricity commissions to ensure the respect, by the various utilities, of consumer price caps and compliance with overall quality of service standards, as well as, to oversee 'pooling' activities by producers and distributors

  20. Pricing regulations in Great Britain

    International Nuclear Information System (INIS)

    Cicoletti, G.

    1993-01-01

    This paper briefly describes the structure and functions of Great Britain's essential electric power regulatory authority institutionalized by the 1989 British Electricity Act, i.e., the Office of Electricity Regulation, OFFER, and the responsibilities and tasks of the head of OFFER - the Director General of Electricity Supply (DGES). In particular, with regard to the latter, the paper describes how the DGES works together with regional electricity commissions to ensure the respect, by the various utilities, of consumer price caps and compliance with overall quality of service standards, as well as, to oversee 'pooling' activities by producers and distributors

  1. What killed Alexander the Great?

    Science.gov (United States)

    Battersby, Cameron

    2007-01-01

    The cause of the death of the Macedonian King, Alexander the Great, at Babylon in 323 BC has excited interest and conjecture throughout the ages. The information available in the surviving ancient sources, none of which is contemporaneous, has been reviewed and compared with modern knowledge as set out in several well-known recent surgical texts. The ancient sources record epic drinking by the Macedonian nobility since at least the time of Phillip II, Alexander's father. Alexander's sudden illness and death is likely to have resulted from a surgical complication of acute alcoholic excess.

  2. Commanders of the Great Victory

    Directory of Open Access Journals (Sweden)

    Anatoly Dmitriyevich Borshchov

    2015-01-01

    Full Text Available The honorary title of «commander» as well as the «admiral» is granted to a military or naval figure on the basis of public recognition of his personal contribution to the success of actions. Generals are usually individuals with creative thinking, the ability to foresee the development of military events. Generals usually have such personality traits as a strong will and determination, rich combat experience, credibility and high organizational skills. In an article dedicated to the 70th anniversary of the Soviet victory in the Great War examines the experience of formation and practice of the most talent-ed Soviet military leaders.

  3. Trends in fishery management of the Great Lakes

    Science.gov (United States)

    Smith, Stanford H.

    1970-01-01

    Some hope is returning for recovery of the fish stocks of the Great Lakes, which have been outstanding examples of abuse although they are the world's largest and most valuable freshwater fishery resource. The lakes and the fish in them have been under complete jurisdiction of sovereign nations and their subdivisions almost since the settlement of north-central North America, but ironically this control has not prevented their decadence. For the first time in the long history of the Great Lakes fishery, management measures have been taken to meliorate conditions that contributed to earlier difficulties.

  4. THE GREAT SILK ROAD BECOMES THE GREAT OIL AND GAS ROAD

    Directory of Open Access Journals (Sweden)

    I. S. Zonn

    2015-01-01

    Full Text Available The Great Silk Road (GSR called so in the late 19th century by German geographer Ferdinand von Richthofen started shaping in the 2nd century B.C. In the minds of peoples the Silk Road is a generalized symbol of trade caravan routes crossing Central Asia, connecting until the 16th century the Far East, in particular Japan, China, with Middle Asia. Appearance in the early 21st century of new independent states in Central Asia along the GSR route was a powerful impetus for revival of the ancient trade route. In September 2013 Xi Jinping, President of the People's Republic of China, during his visit to the Central Asian countries offered the strategic concept of joint construction of the “economic corridor along the Silk Road” based on innovative cooperation in order to revive and consolidate the economic contacts among the Eurasian countries. Establishment of the modern analog of GSR, a powerful transport and pipeline corridor includes the integrated system of railroads and automobile roads, oil and gas pipelines, airlines, and sea lines.

  5. Great apes prefer cooked food.

    Science.gov (United States)

    Wobber, Victoria; Hare, Brian; Wrangham, Richard

    2008-08-01

    The cooking hypothesis proposes that a diet of cooked food was responsible for diverse morphological and behavioral changes in human evolution. However, it does not predict whether a preference for cooked food evolved before or after the control of fire. This question is important because the greater the preference shown by a raw-food-eating hominid for the properties present in cooked food, the more easily cooking should have been adopted following the control of fire. Here we use great apes to model food preferences by Paleolithic hominids. We conducted preference tests with various plant and animal foods to determine whether great apes prefer food items raw or cooked. We found that several populations of captive apes tended to prefer their food cooked, though with important exceptions. These results suggest that Paleolithic hominids would likewise have spontaneously preferred cooked food to raw, exapting a pre-existing preference for high-quality, easily chewed foods onto these cooked items. The results, therefore, challenge the hypothesis that the control of fire preceded cooking by a significant period.

  6. Studying The Great Russian Revolution

    Directory of Open Access Journals (Sweden)

    A. V. Torkunov

    2017-01-01

    Full Text Available The article revises an established view of Russian Revolution as two separate events - February Revolution and October Revolution. The author supports the concept of the «Great Russian Revolution», which unites these two events in a single process of revolutionary development. The author draws attention to the following advantages of the concept under consideration. First, it conceptualizes the revolution as a process contingent of a local and global historical context. In this sense, the revolution is presented as the transition of society to the modern stage of development, meaning the transition to modernity. Second, revolutionary events in Russia are considered from the point of view of the evolution of the spatial and socioeconomic distribution and rearrangement of key social groups: peasantry, elites, national and ethnic minorities. Third, it takes into account the personal factor in the revolutionary events, the influence of individual personalities on escalation or the reduction of socio-political tensions. Fourth, it draws attention to the fact that revolutions imply the use of various forms of political violence. Each revolution is characterized by a unique correlation of forms and intensity of political violence. Finally, it gives a normative assessment of the Revolution, encouraging a national discussion on the results and consequences of this great event.

  7. Central Chile

    Science.gov (United States)

    2002-01-01

    The beginning of spring in central Chile looked like this to SeaWiFS. The snow-covered Andes mark the country's eastern border, and phytoplankton blooms and river sediment plumes fill the waters off its west coast. A large eddy due west of Concepcion is highlighted by the phytoplankton it contains.

  8. Afrique Centrale

    African Journals Online (AJOL)

    PR BOKO

    (Afrique Centrale) : peuplement de protozoaires ciliés et macro invertébrés ... Le lac d'Obili est un écosystème aquatique situé en plein cœur de Yaoundé en ...... électrique des eaux est assez stable, autour de 200 ; ce qui suppose que la ...

  9. Central cell confinement in MFTF-B

    International Nuclear Information System (INIS)

    Jong, R.A.

    1981-01-01

    The point code TANDEM has been used to survey the range of plasma parameters which can be attained in MFTF-B. The code solves for the electron and ion densities and temperatures in the central cell, yin-yang, barrier, and A-cell regions as well as the plasma potential in each region. In these studies, the A-cell sloshing ion beams were fixed while the neutral beams in the yin-yang and central cell, the gas feed in the central cell, and the applied ECRH power β, central cell ion density and temperature, and the confining potential are discussed

  10. Three new sympatric species of Remipedia (Crustacea) from Great Exuma Island, Bahamas Islands

    NARCIS (Netherlands)

    Koenemann, Stefan; Iliffe, Thomas M.; Ham, van der Joris

    2003-01-01

    Three new sympatric species of remipede crustaceans, Speleonectes tanumekes, Speleonectes parabenjamini and Speleonectes minnsi, are described from an anchihaline cave on Great Exuma Island in the central Bahamas. Speleonectes tanumekes is a comparatively long and slender species distinguished by

  11. Lysosomal storage diseases and the blood-brain barrier.

    Science.gov (United States)

    Begley, David J; Pontikis, Charles C; Scarpa, Maurizio

    2008-01-01

    The blood-brain barrier becomes a crucial issue in neuronopathic lysosomal storage diseases for three reasons. Firstly, the function of the blood-brain barrier may be compromised in many of the lysosomal storage diseases and this barrier dysfunction may contribute to the neuropathology seen in the diseases and accelerate cell death. Secondly, the substrate reduction therapies, which successfully reduce peripheral lysosomal storage, because of the blood-brain barrier may not have as free an access to brain cells as they do to peripheral cells. And thirdly, enzyme replacement therapy appears to have little access to the central nervous system as the mannose and mannose-6-phosphate receptors involved in their cellular uptake and transport to the lysosome do not appear to be expressed at the adult blood-brain barrier. This review will discuss in detail these issues and their context in the development of new therapeutic strategies.

  12. Fuzzy barrier distributions

    International Nuclear Information System (INIS)

    Piasecki, E.

    2009-01-01

    Heavy-ion collisions often produce a fusion barrier distribution with structures displaying a fingerprint of couplings to highly collective excitations [1]. Basically the same distribution can be obtained from large-angle quasi-elastic scattering, though here the role of the many weak direct-reaction channels is unclear. For 2 0N e + 9 0Z r we have observed the barrier structures expected for the highly deformed neon projectile, but for 2 0N e + 9 2Z r we find completely smooth distribution (see Fig.1). We find that transfer channels in these systems are of similar strength but single particle excitations are significantly stronger in the latter case. They apparently reduce the 'resolving power' of the quasi-elastic channel, what leads to smeared out, or 'fuzzy' barrier distribution. This is the first case when such a phenomenon has been observed.(author)

  13. Health Barriers to Learning

    Directory of Open Access Journals (Sweden)

    Delaney Gracy

    2014-01-01

    Full Text Available This article summarizes the results from a 2013 online survey with 408 principals and assistant principals in New York City public elementary and middle schools. The survey assessed three primary areas: health issues in the school, health issues perceived as barriers to learning for affected students, and resources needed to address these barriers. Eighteen of the 22 health conditions listed in the survey were considered a moderate or serious issue within their schools by at least 10% of respondents. All 22 of the health issues were perceived as a barrier to learning by between 12% and 87% of the respondents. Representatives from schools that serve a higher percentage of low-income students reported significantly higher levels of concern about the extent of health issues and their impact on learning. Respondents most often said they need linkages with organizations that can provide additional services and resources at the school, especially for mental health.

  14. QUALITY ASSURANCE/QUALITY CONTROL OF A PROJECT INVOLVING COOPERATIVE AGREEMENTS, INTRA-AGENCY AGREEMENTS, AGENCY STAFF AND CONTRACTS TO CONDUCT RESEARCH: ECOLOGICAL MONITORING AND ASSESSMENT OF THE GREAT RIVERS ECOSYSTEMS IN THE CENTRAL BASIN OF THE UNITED STATES (EMAP-GRE)

    Science.gov (United States)

    While condition reports are useful to managers, demonstrating how to implement a monitoring and assessment program in the future is also an important project goal. Better monitoring methods will make more information more widely available to better manage the nation's great rive...

  15. The Great Hedge of India

    International Nuclear Information System (INIS)

    Moxham, Roy

    2015-01-01

    The 'Great Hedge of India', a 3 700 kilometre-long hedge installed by the British customs to safeguard the colonial salt tax system and avoid salt smuggling totally faded from both memory and records (e.g. maps) in less than a century. Roy Moxham found traces of the hedge in a book footnote and searched it for several years until he found its meagre remains. The speaker wrote a book about this quest. He said that this story reveals how things disappear when they are no longer useful and, especially, when they are linked to parts of history that are not deemed particularly positive (the hedge was a means of colonial power)

  16. Gypsum karst in Great Britain

    Directory of Open Access Journals (Sweden)

    Cooper A.H.

    1996-01-01

    Full Text Available In Great Britain the most spectacular gypsum karst development is in the Zechstein gypsum (late Permian mainly in north-eastern England. The Midlands of England also has some karst developed in the Triassic gypsum in the vicinity of Nottingham. Along the north-east coast, south of Sunderland, well-developed palaeokarst, with magnificent breccia pipes, was produced by dissolution of Permian gypsum. In north-west England a small gypsum cave system of phreatic origin has been surveyed and recorded. A large actively evolving phreatic gypsum cave system has been postulated beneath the Ripon area on the basis of studies of subsidence and boreholes. The rate of gypsum dissolution here, and the associated collapse lead to difficult civil engineering and construction conditions, which can also be aggravated by water abstraction.

  17. Great-Britain at CERN

    CERN Multimedia

    C. Laignel

    2004-01-01

    From 23 to 25 November 2004 Administration Building Bldg 60/61 - ground and 1st floor 09.30 - 17.30 Twenty five companies will present their latest technology at the "Great-Britain at CERN" exhibition. British industry will exhibit products and technologies which are related to the field of particle physics. The main subjects are: electrical engineering, electronics, mechanical engineering, vacuum & low temperatures technologies, particles detectors and telecommunications. The exhibition is organised by BEAMA Exhibitions, The British Electrotechnical and Allied Manufacturer's Association There follows : the list of exhibitors. A detailed programme will be available in due course at : your Departemental secretariat, the reception information desk, Building 33, the exhibition. A detailed list of firms is available under the following FI link: http://fi-dep.web.cern.ch/fi-dep/structure/memberstates/exhibitions_visits.htm 1 Accles & Pollock 2 A S Scientific Products Ltd 3 C...

  18. Great Basin Experimental Range: Annotated bibliography

    Science.gov (United States)

    E. Durant McArthur; Bryce A. Richardson; Stanley G. Kitchen

    2013-01-01

    This annotated bibliography documents the research that has been conducted on the Great Basin Experimental Range (GBER, also known as the Utah Experiment Station, Great Basin Station, the Great Basin Branch Experiment Station, Great Basin Experimental Center, and other similar name variants) over the 102 years of its existence. Entries were drawn from the original...

  19. The origin of 'Great Walls'

    International Nuclear Information System (INIS)

    Shandarin, Sergei F.

    2009-01-01

    A new semi-analytical model that explains the formation and sizes of the 'great walls' - the largest structures observed in the universe is suggested. Although the basis of the model is the Zel'dovich approximation it has been used in a new way very different from the previous studies. Instead of traditional approach that evaluates the nonlinear density field it has been utilized for identification of the regions in Lagrangian space that after the mapping to real or redshift space (depending on the kind of structure is studied) end up in the regions where shell-crossing occurs. The set of these regions in Lagrangian space form the progenitor of the structure and after the mapping it determines the pattern of the structure in real or redshift space. The particle trajectories have crossed in such regions and the mapping is no longer unique there. The progenitor after mapping makes only one stream in the multi-stream flow regions therefore it does not comprise all the mass. Nevertheless, it approximately retains the shape of the structure. The progenitor of the structure in real space is determined by the linear density field along with two non-Gaussian fields derived from the initial potential. Its shape in Eulerian space is also affected by the displacement field. The progenitor of the structure in redshift space also depends on these fields but in addition it is strongly affected by two anisotropic fields that determine the pattern of great walls as well as their huge sizes. All the fields used in the mappings are derived from the linear potential smoothed at the current scale of nonlinearity which is R nl = 2.7 h −1 Mpc for the adopted parameters of the ΛCDM universe normalized to σ 8 = 0.8. The model predicts the existence of walls with sizes significantly greater than 500 h −1 Mpc that may be found in sufficiently large redshift surveys

  20. The Great Warming Brian Fagan

    Science.gov (United States)

    Fagan, B. M.

    2010-12-01

    The Great Warming is a journey back to the world of a thousand years ago, to the Medieval Warm Period. Five centuries of irregular warming from 800 to 1250 had beneficial effects in Europe and the North Atlantic, but brought prolonged droughts to much of the Americas and lands affected by the South Asian monsoon. The book describes these impacts of warming on medieval European societies, as well as the Norse and the Inuit of the far north, then analyzes the impact of harsh, lengthy droughts on hunting societies in western North America and the Ancestral Pueblo farmers of Chaco Canyon, New Mexico. These peoples reacted to drought by relocating entire communities. The Maya civilization was much more vulnerable that small-scale hunter-gatherer societies and subsistence farmers in North America. Maya rulers created huge water storage facilities, but their civilization partially collapsed under the stress of repeated multiyear droughts, while the Chimu lords of coastal Peru adapted with sophisticated irrigation works. The climatic villain was prolonged, cool La Niñalike conditions in the Pacific, which caused droughts from Venezuela to East Asia, and as far west as East Africa. The Great Warming argues that the warm centuries brought savage drought to much of humanity, from China to Peru. It also argues that drought is one of the most dangerous elements in today’s humanly created global warming, often ignored by preoccupied commentators, but with the potential to cause over a billion people to starve. Finally, I use the book to discuss the issues and problems of communicating multidisciplinary science to the general public.

  1. Barriers to adherence in adolescents and young adults with cystic fibrosis

    DEFF Research Database (Denmark)

    Bregnballe, Vibeke; Schiøtz, Peter Oluf; Boisen, Kirsten A

    2011-01-01

    Treatment adherence is crucial in patients with cystic fibrosis, but poor adherence is a problem, especially during adolescence. Identification of barriers to treatment adherence and a better understanding of how context shapes barriers is of great importance in the disease. Adolescent reports of...... of barriers to adherence have been studied, but studies of their parents' experience of such barriers have not yet been carried out. The aim of the present study was to explore barriers to treatment adherence identified by young patients with cystic fibrosis and by their parents....

  2. Navigating the Great Recession: what role for monetary policy?

    OpenAIRE

    Bank for International Settlements

    2013-01-01

    The 12th BIS Annual Conference took place in Lucerne, Switzerland on 20-21 June 2013. The event brought together a distinguished group of central bank governors, leading academics and former public officials to exchange views on the conference theme of "Navigating the Great Recession: what role for monetary policy?". This volume contains the opening address by Stephen Cecchetti (former Economic Adviser, BIS), a keynote address by Finn Kydland (University of California, Santa Barbara) and the ...

  3. Europa central

    Directory of Open Access Journals (Sweden)

    Karel BARTOSEK

    2010-02-01

    Full Text Available La investigación francesa continúa interesándose por Europa Central. Desde luego, hay límites a este interés en el ambiente general de mi nueva patria: en la ignorancia, producto del largo desinterés de Francia por este espacio después de la Segunda Guerra Mundial, y en el comportamiento y la reflexión de la clase política y de los medios de comunicación (una anécdota para ilustrar este ambiente: durante la preparación de nuestro coloquio «Refugiados e inmigrantes de Europa Central en el movimiento antifascista y la Resistencia en Francia, 1933-1945», celebrado en París en octubre de 1986, el problema de la definición fue planteado concreta y «prácticamente». ¡Y hubo entonces un historiador eminente, para quién Alemania no formaría parte de Europa Central!.

  4. The great supernova of 1987

    International Nuclear Information System (INIS)

    Woosley, S.E.

    1989-01-01

    Seven hundred day after the explosion of the brightest supernova in four centuries, astronomers continue to be both excited and perplexed by its behavior. By now, the supernova has received considerably attention in the literature. This paper emphasizes several aspects of the supernova that continue to be of special interest. These include: the evolution of the presupernova star, why it was blue, what its composition and core structure were; the iron core mass, explosion mechanism, and certain aspects of the neutrino burst; the detailed isotopic composition of the ejecta; the light curve and the requirement for mixing; the expected continued evolution of the supernova at all wavelengths given both the presence of several radioactivities as well as a central collapsed object as a power source; and late breaking news regarding the pulsar

  5. Predicting Great Lakes fish yields: tools and constraints

    Science.gov (United States)

    Lewis, C.A.; Schupp, D.H.; Taylor, W.W.; Collins, J.J.; Hatch, Richard W.

    1987-01-01

    Prediction of yield is a critical component of fisheries management. The development of sound yield prediction methodology and the application of the results of yield prediction are central to the evolution of strategies to achieve stated goals for Great Lakes fisheries and to the measurement of progress toward those goals. Despite general availability of species yield models, yield prediction for many Great Lakes fisheries has been poor due to the instability of the fish communities and the inadequacy of available data. A host of biological, institutional, and societal factors constrain both the development of sound predictions and their application to management. Improved predictive capability requires increased stability of Great Lakes fisheries through rehabilitation of well-integrated communities, improvement of data collection, data standardization and information-sharing mechanisms, and further development of the methodology for yield prediction. Most important is the creation of a better-informed public that will in turn establish the political will to do what is required.

  6. Great Basin Research and Management Project: Restoring and maintaining riparian ecosystem integrity

    Science.gov (United States)

    Jeanne C. Chambers

    2000-01-01

    The Great Basin Research and Management Project was initiated in 1994 by the USDA Forest Service, Rocky Mountain Research Station’s Ecology, Paleoecology, and Restoration of Great Basin Watersheds Project to address the problems of stream incision and riparian ecosystem degradation in central Nevada. It is a highly interdisciplinary project that is being conducted in...

  7. Revitalising the public open spaces in the CDB of Pietermaritzburg to immortalize a great place

    CSIR Research Space (South Africa)

    Ndaba, DN

    2014-10-01

    Full Text Available , social and economic node with a rich cultural heritage and a CBD that is the administrative central authority of the province. It’s internationally acclaimed competitions and sports give it global appeal. Great cities are also made by great public places...

  8. Barrier Data Base user's guide

    International Nuclear Information System (INIS)

    Worrell, R.B.; Gould, D.J.; Wall, D.W.

    1977-06-01

    A special purpose data base for physical security barriers has been developed. In addition to barriers, the entities accommodated by the Barrier Data Base (BDB) include threats and references. A threat is established as a configuration of people and equipment which has been employed to penetrate (or attempt to penetrate) a barrier. References are used to cite publications pertinent to the barriers and threats in the data base. Utilization and maintenance of the Barrier Data Base is achieved with LIST, QUERY, ENTER, DELETE, and CHANGE commands which are used to manipulate the data base entities

  9. The heart and great vessels

    International Nuclear Information System (INIS)

    Condon, V.

    1985-01-01

    Heart disease is the fifth most common cause of death in infants and children (preceded by anoxic and hypoxic conditions, gross congenital malformations, accidental death, and immaturity). Of all the cardiac lesions, congenital heart disease (CHD) makes up the gross majority, accounting for approximately 90% of all cardiac deaths. Approximately two-thirds of all infants who die from CHD do so within the first year of life; of these, approximately one-third die within the first month. The most common cause of death in the first month is hypoplastic left heart syndrome and lesions associated with it, i.e., aortic atresia/critical aortic stenosis and mitral atresia/critical mitral stenosis. Severe coarctation of the aorta (coarctation syndrome) and transposition of the great arteries are the other most important causes of death in this age group. CHD occurs as a familial condition in approximately 1-4% of cases; ventricular septal defects, patent ductus arteriosus, and atrial septal defect are particularly common forms. Parental age plays an important role, with a significantly increased risk of CHD in infants of mothers over 39 years of age. Patent ductus arteriosus is more prevalent in firstborn children, particularly those born prematurely to young mothers. Environmental factors, such as exposure to teratogenic agents, have also been shown to increase the incidence of CHD. Children with various syndromes also have increased incidence of CHD. Down syndrome is a classic example, as are other trisomies

  10. Tipping Points, Great and Small

    Science.gov (United States)

    Morrison, Foster

    2010-12-01

    The Forum by Jordan et al. [2010] addressed environmental problems of various scales in great detail, but getting the critical message through to the formulators of public policies requires going back to basics, namely, that exponential growth (of a population, an economy, or most anything else) is not sustainable. When have you heard any politician or economist from anywhere across the ideological spectrum say anything other than that more growth is essential? There is no need for computer models to demonstrate “limits to growth,” as was done in the 1960s. Of course, as one seeks more details, the complexity of modeling will rapidly outstrip the capabilities of both observation and computing. This is common with nonlinear systems, even simple ones. Thus, identifying all possible “tipping points,” as suggested by Jordan et al. [2010], and then stopping just short of them, is impractical if not impossible. The main thing needed to avoid environmental disasters is a bit of common sense.

  11. The great East Japan earthquake

    Energy Technology Data Exchange (ETDEWEB)

    Fluke, R.

    2011-06-15

    'Full text:' More formally called the Tohoku-Chihou-Taiheiyo-Oki Earthquake of March 11, 2011, it was the ensuing tsunami that caused the most death and destruction to the north-east coastal region of Japan. It is also what caused the multiple meltdowns at Fukushima Dai-ichi. Reactor Unit 1, ironically, was scheduled to be permanently shut down for decommissioning just two weeks later. The Fukushima Dai-ichi nuclear power plant has a tsunami protection barrier designed for the worst recorded tsunami in that area since 1896 - to a height of 5.7 m. The plant itself is on an elevated grade of about 10 m. The tsunami, reported to be 14-15 m, caused inundation of the entire site with at least four metres of seawater. The seawater flooded the turbine building and damaged electrical equipment including the emergency diesel generators, leaving the entire six-unit nuclear power plan without any source of AC power, known as the 'station blackout scenario'. There are numerous reports available on-line at various sites. The Japanese Government report is frank and forthcoming on the causes and the lessons learned, and the lAEA Mission report is in-depth and well presented, not only as a factual account of the events but as a unified source of the conclusions and lessons learned. Photos of the catastrophe are available at the TEPCO web site: http://www.tepco.co.jp/en/index-e.html. In this edition of the Bulletin there is a 'layman's' description of CANDU and BWR design in terms of the fundamental safety principles - Control, Cool and Contain as well as a description of how these principles were met, or not met at Fukushima Dai-ichi. Also, an excerpt from the IAEA Expert Mission is included. We 'technocrats' sometimes forget about the human aspects of a nuclear disaster. An essay by Dr. Michael Edwards is included entitled 'Psychology, Philosophy and Nuclear Science'. Other references to the events appear throughout this

  12. The great East Japan earthquake

    International Nuclear Information System (INIS)

    Fluke, R.

    2011-01-01

    'Full text:' More formally called the Tohoku-Chihou-Taiheiyo-Oki Earthquake of March 11, 2011, it was the ensuing tsunami that caused the most death and destruction to the north-east coastal region of Japan. It is also what caused the multiple meltdowns at Fukushima Dai-ichi. Reactor Unit 1, ironically, was scheduled to be permanently shut down for decommissioning just two weeks later. The Fukushima Dai-ichi nuclear power plant has a tsunami protection barrier designed for the worst recorded tsunami in that area since 1896 - to a height of 5.7 m. The plant itself is on an elevated grade of about 10 m. The tsunami, reported to be 14-15 m, caused inundation of the entire site with at least four metres of seawater. The seawater flooded the turbine building and damaged electrical equipment including the emergency diesel generators, leaving the entire six-unit nuclear power plan without any source of AC power, known as the 'station blackout scenario'. There are numerous reports available on-line at various sites. The Japanese Government report is frank and forthcoming on the causes and the lessons learned, and the lAEA Mission report is in-depth and well presented, not only as a factual account of the events but as a unified source of the conclusions and lessons learned. Photos of the catastrophe are available at the TEPCO web site: http://www.tepco.co.jp/en/index-e.html. In this edition of the Bulletin there is a 'layman's' description of CANDU and BWR design in terms of the fundamental safety principles - Control, Cool and Contain as well as a description of how these principles were met, or not met at Fukushima Dai-ichi. Also, an excerpt from the IAEA Expert Mission is included. We 'technocrats' sometimes forget about the human aspects of a nuclear disaster. An essay by Dr. Michael Edwards is included entitled 'Psychology, Philosophy and Nuclear Science'. Other references to the events appear throughout this edition.(author)

  13. central t

    Directory of Open Access Journals (Sweden)

    Manuel R. Piña Monarrez

    2007-01-01

    Full Text Available Dado que la Regresión Ridge (RR, es una estimación sesgada que parte de la solución de la regresión de Mínimos Cuadrados (MC, es vital establecer las condiciones para las que la distribución central t de Student que se utiliza en la prueba de hipótesis en MC, sea también aplicable a la regresión RR. La prueba de este importante resultado se presenta en este artículo.

  14. Assessment of biomass cogeneration in the Great Lakes region

    International Nuclear Information System (INIS)

    Burnham, M.; Easterly, J.L.

    1994-01-01

    Many biomass cogeneration facilities have successfully entered into power sales agreements with utilities across the country, often after overcoming various difficulties or barriers. Under a project sponsored by the Great Lakes Regional Biomass Energy Program of the U.S. Department of Energy, DynCorp sm-bullet Meridian has conducted a survey of biomass facilities in the seven Great Lakes states, selecting 10 facilities for case studies with at least one facility in each of the seven states. The purpose of the case studies was to address obstacles that biomass processors face in adding power production to their process heat systems, and to provide examples of successful strategies for entering into power sales agreements with utilities. The case studies showed that the primary incentives for investing in cogeneration and power sales are to reduce operating costs through improved biomass waste management and lower energy expenditures. Common barriers to cogeneration and power sales were high utility stand-by charges for unplanned outages and low utility avoided cost payments due to excess utility generation capacity

  15. Central sleep apnea

    Science.gov (United States)

    Sleep apnea - central; Obesity - central sleep apnea; Cheyne-Stokes - central sleep apnea; Heart failure - central sleep apnea ... Central sleep apnea results when the brain temporarily stops sending signals to the muscles that control breathing. The condition ...

  16. Geophysical characterization of subsurface barriers

    International Nuclear Information System (INIS)

    Borns, D.J.

    1995-08-01

    An option for controlling contaminant migration from plumes and buried waste sites is to construct a subsurface barrier of a low-permeability material. The successful application of subsurface barriers requires processes to verify the emplacement and effectiveness of barrier and to monitor the performance of a barrier after emplacement. Non destructive and remote sensing techniques, such as geophysical methods, are possible technologies to address these needs. The changes in mechanical, hydrologic and chemical properties associated with the emplacement of an engineered barrier will affect geophysical properties such a seismic velocity, electrical conductivity, and dielectric constant. Also, the barrier, once emplaced and interacting with the in situ geologic system, may affect the paths along which electrical current flows in the subsurface. These changes in properties and processes facilitate the detection and monitoring of the barrier. The approaches to characterizing and monitoring engineered barriers can be divided between (1) methods that directly image the barrier using the contrasts in physical properties between the barrier and the host soil or rock and (2) methods that reflect flow processes around or through the barrier. For example, seismic methods that delineate the changes in density and stiffness associated with the barrier represents a direct imaging method. Electrical self potential methods and flow probes based on heat flow methods represent techniques that can delineate the flow path or flow processes around and through a barrier

  17. DNA nanovehicles and the biological barriers

    DEFF Research Database (Denmark)

    Okholm, Anders Hauge; Kjems, Jørgen

    2016-01-01

    DNA is emerging as a smart material to construct nanovehicles for targeted drug delivery. The programmability of Watson-Crick base paring enables construction of defined and dynamic DNA nanostructures of almost arbitrary shape and DNA can readily be functionalized with a variety of molecular...... be overcome. Here, we highlight recent strategies for DNA nanostructures in drug delivery, DNA nanovehicles, to facilitate targeting and crossing of the biological barriers. In light of this, we discuss future solutions and challenges for DNA nanovehicles to unravel their great potential to facilitate...

  18. Chaotic correlations in barrier billiards with arbitrary barriers

    International Nuclear Information System (INIS)

    Osbaldestin, A H; Adamson, L N C

    2013-01-01

    We study autocorrelation functions in symmetric barrier billiards for golden mean trajectories with arbitrary barriers. Renormalization analysis reveals the presence of a chaotic invariant set and thus that, for a typical barrier, there are chaotic correlations. The chaotic renormalization set is the analogue of the so-called orchid that arises in a generalized Harper equation. (paper)

  19. The Great Depression and the Great Recession: A Comparative Analysis of their Analogies

    Directory of Open Access Journals (Sweden)

    Cristina Peicuti

    2014-06-01

    Full Text Available The decades preceding the Great Depression and the U.S. subprime mortgage crisis have close similarities. Both decades were characterized by rapid growth without major contractions, by an increase in liquidity, a lack of inflation, and a generalized decrease in risk premiums. Additional similarities included significant changes in the financing of real estate by commercial banks along with a consolidation of the banking sector and high hopes that the efficiency of monetary policy would prevent financial crises. These decades were also characterized by the consolidation of the powers of young central banks (the Federal Reserve System in the 1920s and the European Central Bank in the 2000s, by unsuccessful attempts to control market speculation, by their international dimensions, and by the eruption of crises after the failure of a major American financial institution that could have been avoided. Understanding these analogies help us better identify the causes of the subprime mortgage crisis and prevent history from repeating itself to the extentof such large-scale devastating consequences.

  20. Electrolyte diffusion in compacted montmorillonite engineered barriers

    International Nuclear Information System (INIS)

    Jahnke, F.M.; Radke, C.J.

    1985-09-01

    The bentonite-based engineered barrier or packing is a proposed component of several designs conceived to dispose of high-level nuclear waste in geologic repositories. Once radionuclides escape the waste package, they must first diffuse through the highly impermeable clay-rich barrier before they reach the host repository. To determine the effectiveness of the packing as a sorption barrier in the transient release period and as a mass-transfer barrier in the steady release period over the geologic time scales involved in nuclear waste disposal, a fundamental understanding of the diffusion of electrolytes in compacted clays is required. We present, and compare with laboratory data, a model quantifying the diffusion rates of cationic cesium and uncharged tritium in compacted montmorillonite clay. Neutral tritium characterizes the geometry (i.e., tortuosity) of the particulate gel. After accounting for cation exchange, we find that surface diffusion is the dominant mechanism of cation transport, with an approximate surface diffusion coefficient of 2 x 10 -6 cm 2 /s for cesium. This value increases slightly with increasing background ionic strength. The implications of this work for the packing as a migration barrier are twofold. During the transient release period, K/sub d/ values are of little importance in retarding ion migration. This is because sorption also gives rise to a surface diffusion path, and it is surface diffusion which controls the diffusion rate of highly sorbing cations in compacted montmorillonite. During the steady release period, the presence of surface diffusion leads to a flux through the packing which is greatly enhanced. In either case, if surface diffusion is neglected, the appropriate diffusion coefficient of ions in compacted packing will be in considerable error relative to current design recommendations. 11 refs., 4 figs., 1 tab

  1. Design of engineered sorbent barriers

    International Nuclear Information System (INIS)

    Jones, E.O.; Freeman, H.D.

    1988-08-01

    A sorbent barrier uses sorbent material such as activated carbon or natural zeolites to prevent the migration of radionuclides from a low-level waste site to the aquifer. The sorbent barrier retards the movement of radioactive contaminants, thereby providing time for the radionuclides to decay. Sorbent barriers can be a simple, effective, and inexpensive method for reducing the migration of radionuclides to the environment. Designing a sorbent barrier consists of using soil and sorbent material properties and site conditions as input to a model which will determine the necessary sorbent barrier thickness to meet contaminant limits. The paper will cover the following areas: techniques for measuring sorption properties of barrier materials and underlying soils, use of a radionuclide transport model to determine the required barrier thickness and performance under a variety of site conditions, and cost estimates for applying the barrier. 8 refs., 6 figs., 1 tab

  2. Design of engineered sorbent barriers

    International Nuclear Information System (INIS)

    Jones, E.O.; Freeman, H.D.

    1988-01-01

    A sorbent barrier uses sorbent material such as activated carbon or natural zeolites to prevent the migration of radionuclides from a low-level waste site to the aquifer. The sorbent barrier retards the movement of radioactive contaminants, thereby providing time for the radionuclides to decay. Sorbent barriers can be a simple, effective, and inexpensive method for reducing the migration of radionuclides to the environment. Designing a sorbent barrier consists of using soil and sorbent material properties and site conditions as input to a model which will determine the necessary sorbent barrier thickness to meet contaminant limits. The paper covers the following areas: techniques for measuring sorption properties of barrier materials and underlying soils, use of a radionuclide transport model to determine the required barrier thickness and performance under a variety of site conditions, and cost estimates for applying the barrier

  3. Policy processes and decision making of environmental policy in Great Britain and France. Vol. 1

    International Nuclear Information System (INIS)

    Schreiber, H.

    1991-01-01

    Research of central aspects of British environmental policy. This report concentrates on the role of the constitutional system of environmental policy, on the evaluation of a growing of 'Green Policy' in Great Britain, on the central problems of environmental policy and finally on the role of international environmental policy for Great Britain and Great Britain's role in international environmental activities. Beyond that this report contains a presentation of the state of the British environment (Pollution: Air, Water, Waste, Soil; Radioactivity and Noise). (orig.) With 205 refs., 18 tabs., 14 figs [de

  4. Role of the Blood-Brain Barrier in the Formation of Brain Metastases

    Directory of Open Access Journals (Sweden)

    István A. Krizbai

    2013-01-01

    Full Text Available The majority of brain metastases originate from lung cancer, breast cancer and malignant melanoma. In order to reach the brain, parenchyma metastatic cells have to transmigrate through the endothelial cell layer of brain capillaries, which forms the morphological basis of the blood-brain barrier (BBB. The BBB has a dual role in brain metastasis formation: it forms a tight barrier protecting the central nervous system from entering cancer cells, but it is also actively involved in protecting metastatic cells during extravasation and proliferation in the brain. The mechanisms of interaction of cancer cells and cerebral endothelial cells are largely uncharacterized. Here, we provide a comprehensive review on our current knowledge about the role of junctional and adhesion molecules, soluble factors, proteolytic enzymes and signaling pathways mediating the attachment of tumor cells to brain endothelial cells and the transendothelial migration of metastatic cells. Since brain metastases represent a great therapeutic challenge, it is indispensable to understand the mechanisms of the interaction of tumor cells with the BBB in order to find targets of prevention of brain metastasis formation.

  5. Does Sympathy Motivate Prosocial Behaviour in Great Apes?

    Science.gov (United States)

    Liebal, Katja; Vaish, Amrisha; Haun, Daniel; Tomasello, Michael

    2014-01-01

    Prosocial behaviours such as helping, comforting, or sharing are central to human social life. Because they emerge early in ontogeny, it has been proposed that humans are prosocial by nature and that from early on empathy and sympathy motivate such behaviours. The emerging question is whether humans share these abilities to feel with and for someone with our closest relatives, the great apes. Although several studies demonstrated that great apes help others, little is known about their underlying motivations. This study addresses this issue and investigates whether four species of great apes (Pongo pygmaeus, Gorilla gorilla, Pan troglodytes, Pan paniscus) help a conspecific more after observing the conspecific being harmed (a human experimenter steals the conspecific’s food) compared to a condition where no harming occurred. Results showed that in regard to the occurrence of prosocial behaviours, only orangutans, but not the African great apes, help others when help is needed, contrasting prior findings on chimpanzees. However, with the exception of one population of orangutans that helped significantly more after a conspecific was harmed than when no harm occurred, prosocial behaviour in great apes was not motivated by concern for others. PMID:24416212

  6. Shottky-barrier formation

    International Nuclear Information System (INIS)

    Guines, F.; Sanchez-Dehesa, J.; Flores, F.

    1983-01-01

    In this paper a realistic selfconsistent calculation of an abrupt metal-semiconductor junction is presented by means of a tight-binding approach. A specific Si-Ag junction has been considered, and the charge neutrality level as well as the barrier height have been determined in good agreement with experiments. For a generaljunction it is shown that the interface properties depend essentially on the characteristics of the first metal layer and its interaction with the semiconductor. (Author) [pt

  7. Energy barrier to decoherence

    International Nuclear Information System (INIS)

    Mizel, Ari; Mitchell, M. W.; Cohen, Marvin L.

    2001-01-01

    We propose a ground-state approach to realizing quantum computers. This scheme is time-independent and inherently defends against decoherence by possessing an energy barrier to excitation. We prove that our time-independent qubits can perform the same algorithms as their time-dependent counterparts. Advantages and disadvantages of the time-independent approach are described. A model involving quantum dots is provided for illustration

  8. Alpha-induced instabilities in tandem thermal barriers

    Energy Technology Data Exchange (ETDEWEB)

    Kammash, T.; Galbraith, D.L.

    1987-01-01

    A major premise in the operation of Tandem Mirror reactors is that the fusion reactions take place in the central cell only. The alpha particles generated by the Deuterium-Tritium (DT) fusions, along with other ions, will however pass from the central cell to the thermal barriers and return to the central cell as a result of reflection by the potential hills that exist by the plugs' side of these barriers. This streaming motion gives rise to electrostatic and electomagnetic instabilities which could detract from the barrier's function as a thermal insulator. The number density and streaming velocity of these passing particles are dictated by the electrostatic potential variation and the magnetic field structure in these regions. It is shown that, in the absence of alphas, barriers with deep potential depression are less susceptible to electrostatic instabilities while particularly vulnerable to unstable electromagnetic modes. In the presence of alphas, especially the fast alphas whose mean energy is significantly larger than the barrier potentials they see, (which is twice as high as that seen by the ions) both types of modes become unstable.

  9. Performance of engineered barriers

    International Nuclear Information System (INIS)

    Rajaram, V.; Dean, P.V.; McLellan, S.A.

    1997-01-01

    Engineered barriers, both vertical and horizontal, have been used to isolate hazardous wastes from contact, precipitation, surface water and groundwater. The primary objective of this study was to determine the performance of subsurface barriers installed throughout the U.S. over the past 20 years to contain hazardous wastes. Evaluation of Resource Conservation and Recovery Act (RCRA) Subtitle C or equivalent caps was a secondary objective. A nationwide search was launched to select hazardous waste sites at which vertical barrier walls and/or caps had been used as the containment method. None of the sites selected had an engineered floor. From an initial list of 130 sites, 34 sites were selected on the basis of availability of monitoring data for detailed analysis of actual field performance. This paper will briefly discuss preliminary findings regarding the design, construction quality assurance/construction quality control (CQA/CQC), and monitoring at the 34 sites. In addition, the short-term performance of these sites (less than 5 years) is presented since very little long-term performance data was available

  10. Fluctuations in Schottky barrier heights

    International Nuclear Information System (INIS)

    Mahan, G.D.

    1984-01-01

    A double Schottky barrier is often formed at the grain boundary in polycrystalline semiconductors. The barrier height is shown to fluctuate in value due to the random nature of the impurity positions. The magnitude of the fluctuations is 0.1 eV, and the fluctuations cause the barrier height measured by capacitance to differ from the one measured by electrical conductivity

  11. Central hypothyroidism

    Directory of Open Access Journals (Sweden)

    Vishal Gupta

    2011-01-01

    Full Text Available Central hypothyroidism is defined as hypothyroidism due to insufficient stimulation by thyroid stimulating hormone (TSH of an otherwise normal thyroid gland. It has an estimated prevalence of approximately 1 in 80,000 to 1 in 120,000. It can be secondary hypothyroidism (pituitary or tertiary hypothyroidism (hypothalamus in origin. In children, it is usually caused by craniopharyngiomas or previous cranial irradiation for brain tumors or hematological malignancies. In adults, it is usually due to pituitary macroadenomas, pituitary surgeries or post-irradiation. Fatigue and peripheral edema are the most specific clinical features. Diagnosis is established by the presence of normal to low-normal TSH on the background of low-normal thyroid hormones, confirmed by the thyrotropin releasing hormone stimulation test. Therapy includes use of levothyroxine titrated to improvement in symptomology and keeping free T4 in the upper limit of normal reference range.

  12. On the Existence of Compositional Barrier Certificates

    DEFF Research Database (Denmark)

    Sloth, Christoffer; Wisniewski, Rafael; Pappas, George J.

    2012-01-01

    This paper provides a necessary and sufficient condition for the compositional verification of a continuous system with additively separable barrier functions. The compositional safety verification enables the verification of an interconnection of subsystems. The idea behind the compositional...... of a system that cannot be verified using the compositional method, but can be verified using a centralized method. This example highlights how not to decompose systems, and should be used to guide the decomposition of a system into appropriate subsystems. Finally, we provide a second condition...

  13. The corallivorous invertebrate Drupella aids in transmission of brown band disease on the Great Barrier Reef

    Science.gov (United States)

    Nicolet, K. J.; Hoogenboom, M. O.; Gardiner, N. M.; Pratchett, M. S.; Willis, B. L.

    2013-06-01

    Brown band disease (BrB) is an increasingly prevalent coral disease in the Indo-Pacific, but although the macroscopic signs of BrB have been associated with the ciliate Philaster guamensis, many aspects of its ecology remain unknown, particularly how the disease is transmitted among coral colonies. The aim of this study was to assess biotic factors affecting BrB transmission, explicitly testing whether corallivorous species contribute to disease spread. Several fish species were observed feeding on diseased tissue in the field, but did not influence either the progression or transmission rates of BrB on coral colonies in situ. In aquarium-based experiments, the butterflyfish Chaetodon aureofasciatus neither aided nor hindered the transmission of BrB from infected to uninfected corals. In contrast, the coral-feeding gastropod Drupella sp. was a highly effective vector of BrB, infecting more than 40 % of experimental colonies. This study also demonstrated the importance of injury in facilitating BrB infection, supporting the hypothesis that the BrB pathogen invades compromised coral tissue. In conclusion, disturbances and corallivorous activities that injure live corals are likely to contribute to increased occurrence of BrB provided that feeding scars create entry wounds sufficiently extensive to facilitate infection. These findings increase the understanding of the ecology of BrB, enabling better predictions of the prevalence and severity of this disease, and informing strategies for managing the impact of BrB on coral reefs.

  14. Deposition of organic material in a coral reef lagoon, One Tree Island, Great Barrier Reef

    Science.gov (United States)

    Koop, K.; Larkum, A. W. D.

    1987-07-01

    Deposition of organic material was measured at four sites on One Tree Island coral reef using fixed sediment traps. Although no reliable data were obtained for the reef crest area because of problems of resuspension, mean deposition in the backreef area amounted to some 4 g organic C m -2 day -1 whereas in the lagoon it was about 1·5 g C m -2 day -1. This amounted to mean nitrogen deposition rates of 160 and 95 mg N m -2 day -1, respectively. As primary production by turf algae, the principal producers at One Tree Island, has been estimated at about 2·3 g C m -2 day -1 for the whole reef system and the weighted mean carbon deposition is estimated at 2·2 g C m -2 day -1, it is clear that the carbon produced by plants is largely retained in the system. Nitrogen deposition, on the other hand, amounted to only about 60% of that produced by turf algae and it must be assumed that much of this leached into the water during sedimentation. Losses of nitrogen may be minimized by incorporation of dissolved nitrogen by pelagic microheterotrophs which may in turn be consumed by filter feeders before they leave the reef.

  15. Adaptive management of the great barrier reef and the Grand Canyon world heritage areas

    NARCIS (Netherlands)

    Hughes, T.P.; Gunderson, L.H.; Folke, C.; Scheffer, M.

    2007-01-01

    Conventional perceptions of the interactions between people and their environment are rapidly transforming. Old paradigms that view humans as separate from nature, natural resources as inexhaustible or endlessly substitutable, and the world as stable, predictable, and in balance are no longer

  16. Lichen Monitoring Delineates Biodiversity on a Great Barrier Reef Coral Cay

    Directory of Open Access Journals (Sweden)

    Paul C. Rogers

    2015-05-01

    Full Text Available Coral islands around the world are threatened by changing climates. Rising seas, drought, and increased tropical storms are already impacting island ecosystems. We aim to better understand lichen community ecology of coral island forests. We used an epiphytic lichen community survey to gauge Pisonia (Pisonia grandis R.BR., which dominates forest conditions on Heron Island, Australia. Nine survey plots were sampled for lichen species presence and abundance, all tree diameters and species, GPS location, distance to forest-beach edge, and dominant forest type. Results found only six unique lichens and two lichen associates. A Multi-Response Permutation Procedures (MRPP test found statistically distinct lichen communities among forest types. The greatest group differences were between interior Pisonia and perimeter forest types. Ordinations were performed to further understand causes for distinctions in lichen communities. Significant explanatory gradients were distance to forest edge, tree density (shading, and Pisonia basal area. Each of these variables was negatively correlated with lichen diversity and abundance, suggesting that interior, successionally advanced, Pisonia forests support fewer lichens. Island edge and presumably younger forests—often those with greater tree diversity and sunlight penetration—supported the highest lichen diversity. Heron Island’s Pisonia-dominated forests support low lichen diversity which mirrors overall biodiversity patterns. Lichen biomonitoring may provide a valuable indicator for assessing island ecosystems for conservation purposes regionally.

  17. Effects of Great Barrier Reef degradation on recreational reef-trip demand: a contingent behaviour approach

    NARCIS (Netherlands)

    Kragt, M.E.; Roebeling, P.C.; Ruijs, A.J.W.

    2009-01-01

    There is a growing concern that increased nutrient and sediment runoff from river catchments are a potential source of coral reef degradation. Degradation of reefs may affect the number of tourists visiting the reef and, consequently, the economic sectors that rely on healthy reefs for their income

  18. Lichen Monitoring Delineates Biodiversity on a Great Barrier Reef Coral Cay

    OpenAIRE

    Rogers, Paul C.; Rogers, Roderick W.; Hedrich, Anne E.; Moss, Patrick T.

    2015-01-01

    Coral islands around the world are threatened by changing climates. Rising seas, drought, and increased tropical storms are already impacting island ecosystems. We aim to better understand lichen community ecology of coral island forests. We used an epiphytic lichen community survey to gauge Pisonia (Pisonia grandis R.BR.), which dominates forest conditions on Heron Island, Australia. Nine survey plots were sampled for lichen species presence and abundance, all tree diameters and species, GPS...

  19. Diel coral reef acidification driven by porewater advection in permeable sands, Heron Island, Great Barrier Reef

    DEFF Research Database (Denmark)

    Santos, Isaac R.; Glud, Ronnie N.; Maher, Damien

    2011-01-01

    Little is known about how biogeochemical processes in permeable sediments affect the pH of coastal waters. We demonstrate that seawater recirculation in permeable sands can play a major role in proton (H+) cycling in a coral reef lagoon. The diel pH range (up to 0.75 units) in the Heron Island...... lagoon was the broadest ever reported for reef waters, and the night‐time pH (7.69) was comparable to worst‐case scenario predictions for seawater pH in 2100. The net contribution of coarse carbonate sands to the whole system H+ fluxes was only 9% during the day, but approached 100% at night when small...... scale (i.e., flow and topography‐induced pressure gradients) and large scale (i.e., tidal pumping as traced by radon) seawater recirculation processes were synergistic. Reef lagoon sands were a net sink for H+, and the sink strength was a function of porewater flushing rate. Our observations suggest...

  20. The role of plants on isolation barrier systems

    International Nuclear Information System (INIS)

    Link, S.O.; Downs, J.L.; Waugh, W.J.

    1994-11-01

    Surface barriers are used to isolate buried wastes from the environment. Most have been built for short-term isolation. The need to isolate radioactive wastes from the environment requires that the functional integrity of a barrier be maintained for thousands of years. Barrier function strongly depends on vegetation. Plants reduce wind and water erosion and minimize drainage, but may transport contaminants if roots extend into buried wastes. Our review of the function of plants on surface barriers focuses on the role of plants across mesic to arid environments and gives special consideration to studies done at Hanford. The Hanford Barrier Development Program was created to design and test an earthen cover system to inhibit water infiltration, plant and animal intrusion, and wind and water erosion, while isolating buried wastes for at least 1000 years. Studies at the Hanford have shown that plants will significantly interact with the barrier. Plants transpire soil water back into the atmosphere. Deep-rooted perennials best recycle water; soil water may drain through the root zone of shallow-rooted annuals. Lysimeter studies indicate that a surface layer of fine soil with deep-rooted plants precludes drainage even with three times normal precipitation. The presence of vegetation greatly reduces water and wind erosion, but deep-rooted plants pose a threat of biointrusion and contaminant transport. The Hanford barrier includes a buried rock layer and asphalt layer to prevent biointrusion

  1. Physics parameter calculations for a Tandem Mirror Reactor with thermal barriers

    International Nuclear Information System (INIS)

    Boghosian, B.M.; Lappa, D.A.; Logan, B.G.

    1979-01-01

    Thermal barriers are localized reductions in potential between the plugs and the central cell, which effectively insulate trapped plug electrons from the central cell electrons. By then applying electron heating in the plug, it is possible to obtain trapped electron temperatures that are much greater than those of the central cell electrons. This, in turn, effects an increase in the plug potential and central cell confinement with a concomitant decrease in plug density and injection power. Ions trapped in the barrier by collisions are removed by the injection of neutral beams directed inside the barrier cell loss cone; these beam neutrals convert trapped barrier ions to neutrals by charge exchange permitting their escape. We describe a zero-dimensional physics model for this type of reactor, and present some preliminary results for Q

  2. Thermopower in double planar tunnel junctions with ferromagnetic barriers and nonmagnetic electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Wilczyński, M., E-mail: wilczyns@if.pw.edu.pl

    2017-01-01

    The Seebeck effect is investigated in double planar tunnel junctions consisting of nonmagnetic electrodes and the central layer separated by ferromagnetic barriers. Calculations are performed in the linear response theory using the free-electron model. The thermopower is analyzed as a function of the thickness of the central layer, temperature of the junctions and the relative orientation of magnetic moments of the barriers. It has been found that the thermopower can be significantly enhanced in the junction with special central layer thickness due to electron tunneling by resonant states. The thickness of the central layer for which the thermopower is enhanced depends not only on the temperature of the junction but also on the orientation of magnetic moments in the barriers. - Highlights: • Thermopower in the double planar junctions with magnetic barriers is analyzed. • Thermopower can be enhanced due to the resonant tunneling. • Thermopower depends on the magnetic configuration of the junction.

  3. Potential Pathways for CNS Drug Delivery Across the Blood-Cerebrospinal Fluid Barrier

    OpenAIRE

    Strazielle, Nathalie; Ghersi-Egea, Jean-Fran?ois

    2016-01-01

    The blood-brain interfaces restrict the cerebral bioavailability of pharmacological compounds. Various drug delivery strategies have been developed to improve drug penetration into the brain. Most strategies target the microvascular endothelium forming the blood-brain barrier proper. Targeting the blood-cerebrospinal fluid (CSF) barrier formed by the epithelium of the choroid plexuses in addition to the blood-brain barrier may offer added-value for the treatment of central nervous system dise...

  4. Continuing Education Preferences, Facilitators, and Barriers for Nursing Home Nurses.

    Science.gov (United States)

    Dyck, Mary J; Kim, Myoung Jin

    2018-01-01

    The purpose of the study was to determine the continuing education needs for nursing home nurses in rural central Illinois and to determine any potential facilitators or barriers to obtaining continuing education. Data were collected using the Educational Needs Assessment questionnaire. Descriptive statistics were computed to examine continuing education preferences, facilitators, and barriers among nursing home nurses. Independent samples t tests were used to compare preferences between administrative and staff nurses. The sample included 317 nurses from 34 facilities. The five top needs were related to clinical problems. Administrative nurses had greater needs for professional issues, managerial skills, and quality improvement than staff nurses. Barriers included rural settings, need for vacation time for programs, and inadequate staffing. Continuing education needs of nursing home nurses in Illinois are similar to previous studies conducted in Arizona and North Carolina. Continuing education barriers were mostly organizational, rather than personal. J Contin Nurs Educ. 2018;49(1):26-33. Copyright 2018, SLACK Incorporated.

  5. John Hennessey, Barrier Breaker

    Science.gov (United States)

    Nelson, Stephen J.

    2018-01-01

    John Hennessey lived a remarkable, full life as a professor, as a leader in his field of management and business, and moral, ethical leadership, and as dean at Dartmouth College's Tuck School of Business and provost at the University of Vermont. He was extraordinary on many fronts, a great man who lived in tumultuous times marked by world war as a…

  6. Crossing the Salt Barrier

    Indian Academy of Sciences (India)

    either the sea or freshwater (rivers, lakes, ponds, etc.), or brackish ... by use of the term osmol (Osm) where, for ... much lower than EE and a fresh water fish lives in an environment where just ..... than prophyropsin, vision is greatly improved.

  7. Barrier mechanisms in the Drosophila blood-brain barrier

    Directory of Open Access Journals (Sweden)

    Samantha Jane Hindle

    2014-12-01

    Full Text Available The invertebrate blood-brain barrier field is growing at a rapid pace and, in recent years, studies have shown a physiologic and molecular complexity that has begun to rival its vertebrate counterpart. Novel mechanisms of paracellular barrier maintenance through GPCR signaling were the first demonstrations of the complex adaptive mechanisms of barrier physiology. Building upon this work, the integrity of the invertebrate blood-brain barrier has recently been shown to require coordinated function of all layers of the compound barrier structure, analogous to signaling between the layers of the vertebrate neurovascular unit. These findings strengthen the notion that many blood-brain barrier mechanisms are conserved between vertebrates and invertebrates, and suggest that novel findings in invertebrate model organisms will have a significant impact on the understanding of vertebrate BBB functions. In this vein, important roles in coordinating localized and systemic signaling to dictate organism development and growth are beginning to show how the blood-brain barrier can govern whole animal physiologies. This includes novel functions of blood-brain barrier gap junctions in orchestrating synchronized neuroblast proliferation, and of blood-brain barrier secreted antagonists of insulin receptor signaling. These advancements and others are pushing the field forward in exciting new directions. In this review, we provide a synopsis of invertebrate blood-brain barrier anatomy and physiology, with a focus on insights from the past 5 years, and highlight important areas for future study.

  8. Parallax barrier engineering for image quality improvement in an autostereoscopic 3D display.

    Science.gov (United States)

    Kim, Sung-Kyu; Yoon, Ki-Hyuk; Yoon, Seon Kyu; Ju, Heongkyu

    2015-05-18

    We present a image quality improvement in a parallax barrier (PB)-based multiview autostereoscopic 3D display system under a real-time tracking of positions of a viewer's eyes. The system presented exploits a parallax barrier engineered to offer significantly improved quality of three-dimensional images for a moving viewer without an eyewear under the dynamic eye tracking. The improved image quality includes enhanced uniformity of image brightness, reduced point crosstalk, and no pseudoscopic effects. We control the relative ratio between two parameters i.e., a pixel size and the aperture of a parallax barrier slit to improve uniformity of image brightness at a viewing zone. The eye tracking that monitors positions of a viewer's eyes enables pixel data control software to turn on only pixels for view images near the viewer's eyes (the other pixels turned off), thus reducing point crosstalk. The eye tracking combined software provides right images for the respective eyes, therefore producing no pseudoscopic effects at its zone boundaries. The viewing zone can be spanned over area larger than the central viewing zone offered by a conventional PB-based multiview autostereoscopic 3D display (no eye tracking). Our 3D display system also provides multiviews for motion parallax under eye tracking. More importantly, we demonstrate substantial reduction of point crosstalk of images at the viewing zone, its level being comparable to that of a commercialized eyewear-assisted 3D display system. The multiview autostereoscopic 3D display presented can greatly resolve the point crosstalk problem, which is one of the critical factors that make it difficult for previous technologies for a multiview autostereoscopic 3D display to replace an eyewear-assisted counterpart.

  9. Barriers to accessing urethroplasty.

    Science.gov (United States)

    Consolo, Michael J; Syed, Kirin K; Robison, Christopher; McFadden, Jacob; Shalowitz, David I; Brown, Gordon A; Sussman, David O; Figler, Bradley D

    2016-01-01

    Urethroplasty is an effective treatment for men with anterior urethral strictures, but is utilized less frequently than ineffective treatments such as internal urethrotomy. We sought to identify provider-level barriers to urethroplasty. An anonymous online survey was emailed to all Mid-Atlantic American Urological Association members. Six scenarios in which urethroplasty was the most appropriate treatment were presented. Primary outcome was recommendation for urethroplasty in ≥ three clinical scenarios. Other factors measured include practice zip code, urethroplasty training, and proximity to a urethroplasty surgeon. Multivariate logistic regression identified factors associated with increased likelihood of urethroplasty recommendation. Of 670 members emailed, 109 (16%) completed the survey. Final analysis included 88 respondents. Mean years in practice was 17.2. Most respondents received formal training in urethroplasty: 43 (49%) in residency, 5 (6%) in fellowship, and 10 (11%) in both; 48 respondents (55%) had a urethroplasty surgeon in their practice, whereas 18 (20%) had a urethroplasty surgeon within 45 minutes of his or her primary practice location. The only covariate that was associated with an increased likelihood of recommending urethroplasty in ≥ three scenarios was formal urethroplasty training. Most members (68%) reported no barriers to referring patients for urethroplasty; the most common barriers cited were long distance to urethroplasty surgeon (n 5 13, 15%) and concern about complications (n 5 8, 9%). Urethroplasty continues to be underutilized in men with anterior urethral strictures, potentially due to lack of knowledge dissemination and access to a urethroplasty surgeon. Appropriate urethroplasty utilization may increase with greater exposure to urethroplasty in training.

  10. Racial Trade Barriers?

    DEFF Research Database (Denmark)

    Bjerre, Jacob Halvas

    . This paper analyzes the racial policies pursued in the foreign trade and argues that we need to recognize Aryanization as a world-wide policy in order to fully understand its character and possible consequences. I focus on the pre-war period and analyze the case of Denmark from three different perspectives......: perpetrators, victims and bystanders. The analysis will show that race, economy and foreign trade were combined in an attempt to raise racial trade barriers. This forced the question of German racial policies on the Danish government, Danish-Jewish businesses, and German companies involved in foreign trade...

  11. Support or Barrier?

    DEFF Research Database (Denmark)

    Sanden, Guro Refsum; Lønsmann, Dorte

    This study offers a critical look at how corporate-level language management influences front-line language practices among employees in three multinational corporations (MNCs) headquartered in Scandinavia. Based on interview and document data, we examine, firstly, what front-line practices...... employees use to cross language boundaries in their everyday work, and, secondly, how these practices relate to top-down language management in the case companies. Our findings show that employees are often dependent on ad hoc and informal solutions in cross- language situations, which leads us...... to a discussion of how a company’s language policy may be seen as both support and a barrier....

  12. Modelization and simulation of capillary barriers

    International Nuclear Information System (INIS)

    Lisbona Cortes, F.; Aguilar Villa, G.; Clavero Gracia, C.; Gracia Lozano, J.L.

    1998-01-01

    Among the different underground transport phenomena, that due to water flows is of great relevance. Water flows in infiltration and percolation processes are responsible of the transport of hazardous wastes towards phreatic layers. From the industrial and geological standpoints, there is a great interest in the design of natural devices to avoid the flows transporting polluting substances. This interest is increased when devices are used to isolate radioactive waste repositories, whose life is to be longer than several hundred years. The so-called natural devices are those based on the superimposition of material with different hydraulic properties. In particular, the flow retention in this kind stratified media, in unsaturated conditions, is basically due to the capillary barrier effect, resulting from placing a low conductivity material over another with a high hydraulic conductivity. Covers designed from the effect above have also to allow a drainage of the upper layer. The lower cost of these covers, with respect to other kinds of protection systems, and the stability in time of their components make them very attractive. However, a previous investigation to determine their effectivity is required. In this report we present the computer code BCSIM, useful for easy simulations of unsaturated flows in a capillary barrier configuration with drainage, and which is intended to serve as a tool for designing efficient covers. The model, the numerical algorithm and several implementation aspects are described. Results obtained in several simulations, confirming the effectivity of capillary barriers as a technique to build safety covers for hazardous waste repositories, are presented. (Author)

  13. Stability of barrier buckets with zero RF-barrier separations

    Energy Technology Data Exchange (ETDEWEB)

    Ng, K.Y.; /Fermilab

    2005-03-01

    A barrier bucket with very small separation between the rf barriers (relative to the barrier widths) or even zero separation has its synchrotron tune decreasing rather slowly from a large value towards the boundary of the bucket. As a result, large area at the bucket edges can become unstable under the modulation of rf voltage and/or rf phase. In addition, chaotic regions may form near the bucket center and extend outward under increasing modulation. Application is made to those barrier buckets used in the process of momentum mining at the Fermilab Recycler Ring.

  14. 'Great Power Style' in China's Economic Policy

    DEFF Research Database (Denmark)

    Jiang, Yang

    2011-01-01

    China’s ascendance attracts concern, even though Beijing claims to be a responsible great power and tries to demonstrate its ‘great power style’ in economic diplomacy. This article therefore discusses the following questions: to what extent does the current notion and practice of Chinese ‘great...... power style’ in economic diplomacy comply with, or differ from, the criteria of benign hegemony; and what are the major constraining factors? Conceptually, China’s ‘great power style’ is rooted in ancient Chinese political philosophy and institution, but it highly resembles the Western notion of benign...

  15. Performing a local barrier operation

    Science.gov (United States)

    Archer, Charles J; Blocksome, Michael A; Ratterman, Joseph D; Smith, Brian E

    2014-03-04

    Performing a local barrier operation with parallel tasks executing on a compute node including, for each task: retrieving a present value of a counter; calculating, in dependence upon the present value of the counter and a total number of tasks performing the local barrier operation, a base value, the base value representing the counter's value prior to any task joining the local barrier; calculating, in dependence upon the base value and the total number of tasks performing the local barrier operation, a target value of the counter, the target value representing the counter's value when all tasks have joined the local barrier; joining the local barrier, including atomically incrementing the value of the counter; and repetitively, until the present value of the counter is no less than the target value of the counter: retrieving the present value of the counter and determining whether the present value equals the target value.

  16. Alexander the Great's tombolos at Tyre and Alexandria, eastern Mediterranean

    Science.gov (United States)

    Marriner, N.; Goiran, J. P.; Morhange, C.

    2008-08-01

    Tyre and Alexandria's coastlines are today characterised by wave-dominated tombolos, peculiar sand isthmuses that link former islands to the adjacent continent. Paradoxically, despite a long history of inquiry into spit and barrier formation, understanding of the dynamics and sedimentary history of tombolos over the Holocene timescale is poor. At Tyre and Alexandria we demonstrate that these rare coastal features are the heritage of a long history of natural morphodynamic forcing and human impacts. In 332 BC, following a protracted seven-month siege of the city, Alexander the Great's engineers cleverly exploited a shallow sublittoral sand bank to seize the island fortress; Tyre's causeway served as a prototype for Alexandria's Heptastadium built a few months later. We report stratigraphic and geomorphological data from the two sand spits, proposing a chronostratigraphic model of tombolo evolution.

  17. Impurity transport in internal transport barrier discharges on JET

    International Nuclear Information System (INIS)

    Dux, R.

    2002-01-01

    In JET plasmas with internal transport barrier (ITB) the behaviour of metallic and low-Z impurities (C, Ne) was investigated. In ITB discharges with reversed shear, the metallic impurities accumulate in cases with too strong peaking of the density profile, while the concentration of low-Z elements C and Ne is only mildly peaked. The accumulation might be so strong, that the central radiation approximately equals the central heating power followed by a radiative collapse of the transport barrier. The radial location with strong impurity gradients (convective barrier) was identified to be situated inside (not at!) the heat flux barrier. Calculations of neo-classical transport were performed for these discharges, including impurity-impurity collisions. It was found, that the observed Z-dependence of the impurity peaking and the location of the impurity 'barrier' can be explained with neo-classical transport. ITB discharges with monotonic shear show less inward convection and seem to be advantageous with respect to plasma purity. (author)

  18. Barrier rf systems in synchrotrons

    International Nuclear Information System (INIS)

    Bhat, Chandra M.

    2004-01-01

    Recently, many interesting applications of the barrier RF system in hadron synchrotrons have been realized. A remarkable example of this is the development of longitudinal momentum mining and implementation at the Fermilab Recycler for extraction of low emittance pbars for the Tevatron shots. At Fermilab, we have barrier RF systems in four different rings. In the case of Recycler Ring, all of the rf manipulations are carried out using a barrier RF system. Here, the author reviews various uses of barrier rf systems in particle accelerators including some new schemes for producing intense proton beam and possible new applications

  19. Tunnel superpenetrability of potential barriers

    International Nuclear Information System (INIS)

    Zakhariev, B N.

    1982-01-01

    The transmission of two particles through the same barrier is considered. The limiting cases are compared when the particles are joined together in a single particle with double mass-energy and potential and when they pass the barrier independently. As an intermediate case a pair of particles bound in a quasideuteron of a finite size is considered. It is shown that long-range collective correlations of particles (of the superfluidity type and others) simplify very much for them passing through high potential barriers. This happens due to the transfer of the additional energy from the particles outside the barriers to those inside it

  20. Barriers for recess physical activity

    DEFF Research Database (Denmark)

    Pawlowski, Charlotte Skau; Tjørnhøj-Thomsen, Tine; Schipperijn, Jasper

    2014-01-01

    BACKGROUND: Many children, in particular girls, do not reach the recommended amount of daily physical activity. School recess provides an opportunity for both boys and girls to be physically active, but barriers to recess physical activity are not well understood. This study explores gender...... differences in children's perceptions of barriers to recess physical activity. Based on the socio-ecological model four types of environmental barriers were distinguished: natural, social, physical and organizational environment. METHODS: Data were collected through 17 focus groups (at 17 different schools...... this study, we recommend promoting recess physical activity through a combination of actions, addressing barriers within the natural, social, physical and organizational environment....

  1. Microsurgical anatomy of the central core of the brain.

    Science.gov (United States)

    Ribas, Eduardo Carvalhal; Yağmurlu, Kaan; de Oliveira, Evandro; Ribas, Guilherme Carvalhal; Rhoton, Albert

    2017-12-22

    substance region." The caudate nucleus and thalamus lie medial to the internal capsule, as the most medial structures of the central core. While the anterior half of the central core is related to the head of the caudate nucleus, the posterior half is related to the thalamus, and hence to each associated portion of the internal capsule between these structures and the insular surface. The central core stands on top of the brainstem. The brainstem and central core are connected by several white matter pathways and are not separated from each other by any natural division. The authors propose a subdivision of the central core into quadrants and describe each in detail. The functional importance of each structure is highlighted, and surgical approaches are suggested for each quadrant of the central core. CONCLUSIONS As a general rule, the internal capsule and its vascularization should be seen as a parasagittal barrier with great functional importance. This is of particular importance in choosing surgical approaches within this region.

  2. Linguistic Barriers and Bridges

    DEFF Research Database (Denmark)

    Thuesen, Frederik

    2016-01-01

    The influence of language on social capital in low-skill and ethnically diverse workplaces has thus far received very limited attention within the sociology of work. As the ethnically diverse workplace is an important social space for the construction of social relations bridging different social...... groups, the sociology of work needs to develop a better understanding of the way in which linguistic diversity influences the formation of social capital, i.e. resources such as the trust and reciprocity inherent in social relations in such workplaces. Drawing on theories about intergroup contact...... and intercultural communication, this article analyses interviews with 31 employees from two highly ethnically diverse Danish workplaces. The article shows how linguistic barriers such as different levels of majority language competence and their consequent misunderstandings breed mistrust and hostility, whilst...

  3. Countermeasures and barriers

    Energy Technology Data Exchange (ETDEWEB)

    Petersen, Johannes [Oersted - DTU, Automation, Kgs. Lyngby (Denmark)

    2005-10-01

    In 1973 Haddon proposed ten strategies for reducing and avoiding damages based on a model of potential harmful energy transfer (Haddon, 1973). The strategies apply to a large variety of unwanted phenomena. Haddon's pioneering work on countermeasures has had a major influence on later thinking about safety. Considering its impact it is remarkable that the literature offers almost no discussions related to the theoretical foundations of Haddon's countermeasure strategies. The present report addresses a number of theoretical issues related to Haddon's countermeasure strategies, which are: 1) A reformulation and formalization of Haddon's countermeasure strategies. 2) An identification and description of some of the problems associated with the term 'barrier'. 3) Suggestions for a more precise terminology based on the causal structure of countermeasures. 4) Extending the scope of countermeasures to include sign-based countermeasures. (au)

  4. Countermeasures and barriers

    International Nuclear Information System (INIS)

    Petersen, Johannes

    2005-10-01

    In 1973 Haddon proposed ten strategies for reducing and avoiding damages based on a model of potential harmful energy transfer (Haddon, 1973). The strategies apply to a large variety of unwanted phenomena. Haddon's pioneering work on countermeasures has had a major influence on later thinking about safety. Considering its impact it is remarkable that the literature offers almost no discussions related to the theoretical foundations of Haddon's countermeasure strategies. The present report addresses a number of theoretical issues related to Haddon's countermeasure strategies, which are: 1) A reformulation and formalization of Haddon's countermeasure strategies. 2) An identification and description of some of the problems associated with the term 'barrier'. 3) Suggestions for a more precise terminology based on the causal structure of countermeasures. 4) Extending the scope of countermeasures to include sign-based countermeasures. (au)

  5. Thames barrier (flood protection barriers on the Thames)

    International Nuclear Information System (INIS)

    Ilkovic, J.

    2005-01-01

    In this paper the flood protection barriers on the Thames are presented. The flood protection system on the Thames in 1984 was commissioned. During two decades this barrier was used 54 times against to the high water and 34 times against storm-sewage. There is installed buttress type hydroelectric power plant

  6. Great Expectations for Middle School Counselors

    Science.gov (United States)

    Wright, Robert J.

    2012-01-01

    During the Great Recession, 2008 to 2010, school systems scrambled to balance budgets, and the ratio of counselors to students became even larger. To make matters worse, the Great Recession had a major impact on cuts in educational funding. Budget cutbacks tend to occur where the public will be least likely to notice. The loss of teachers and the…

  7. Great Books. What Works Clearinghouse Intervention Report

    Science.gov (United States)

    What Works Clearinghouse, 2011

    2011-01-01

    "Great Books" is a program that aims to improve the reading, writing, and critical thinking skills of students in kindergarten through high school. The program is implemented as a core or complementary curriculum and is based on the Shared Inquiry[TM] method of learning. The purpose of "Great Books" is to engage students in…

  8. Great ape genetic diversity and population history

    DEFF Research Database (Denmark)

    Prado-Martinez, Javier; Sudmant, Peter H; Kidd, Jeffrey M

    2013-01-01

    Most great ape genetic variation remains uncharacterized; however, its study is critical for understanding population history, recombination, selection and susceptibility to disease. Here we sequence to high coverage a total of 79 wild- and captive-born individuals representing all six great ape...

  9. Libraries Achieving Greatness: Technology at the Helm

    Science.gov (United States)

    Muir, Scott P.

    2009-01-01

    Libraries have been around for thousands of years. Many of them are considered great because of their magnificent architecture or because of the size of their collections. This paper offers ten case studies of libraries that have used technology to achieve greatness. Because almost any library can implement technology, a library does not have to…

  10. Recensie "The Great Reset" : Richard Florida

    NARCIS (Netherlands)

    Roy van Dalm

    2010-01-01

    Like the Great Depression and the Long Depression before it, experts have viewed prolonged economic downturns as crises. In The Great Reset , bestselling author Richard Florida argues that we should instead see the recent recession as an opportunity to create entirely new ways of working and living

  11. Design and construction of a deep slurry trench barrier

    International Nuclear Information System (INIS)

    Deming, P.W.

    1997-01-01

    A 24 m (80 ft) deep slurry trench surrounding a former chromium manufacturing facility on the Patapsco River in Baltimore, Maryland was constructed in 1995 to contain groundwater and site Soils, and to reduce the volume of groundwater extracted to maintain an inward gradient. In 1992, an embankment made of crushed stone was constructed in the Patapsco River to make land for barrier construction outboard of the bulkheads, and to protect the barrier. Stability of the slurry-supported trench excavation in the embankment required construction from an elevated work platform. An extended reach backhoe was used to excavate the deep slurry trench and to clean the trench bottom. Soil-Bentonite backfill was prepared at a central mixing area and transported by truck to the perimeter barrier. A synthetic membrane was inserted partially into the backfill for connection to a multimedia cap, and for redundancy and erosion control in the tidal zone. Hydraulic testing of the aquitard contained by the barrier demonstrated excellent performance of the barrier and bottom closure. Detailed definition of subsurface conditions and the closure stratum was necessary for the design and successful construction of the barrier, and is recommended for comparable slurry trench construction projects

  12. Energy barriers in patterned media

    NARCIS (Netherlands)

    de Vries, Jeroen

    2013-01-01

    Due to the fact that thermal activation aids in overcoming the energy barrier, the required field for reversal varies from instance to instance for the same island. This thermally induced switching field distribution can be used to determine the difference in energy barrier of magneticallyweak and

  13. Simulating complex noise barrier reflections

    NARCIS (Netherlands)

    Eerden, F.J.M. van der; Lutgendorf, D.; Roo, F. de

    2011-01-01

    Within the EU FP7 QUIESST project, QUIeting the Environment for a Sustainable Surface Transport, a test method is being developed for the reflectivity of noise barriers. The method needs to account for a complex shape of barriers and the use of various types of absorbing materials. The performance

  14. BARRIERS OF STRATEGIC ALLIANCES ORGANIZATION

    Directory of Open Access Journals (Sweden)

    Vladislav M. Sannikov

    2014-01-01

    Full Text Available General barriers of organization of different types of strategic alliances have beenconsidered in the article. There are several recommendations for overcoming themin cases of international alliances, and in case of work in one state. The article also identified goals and tasks of single coordination center of alliance to overcome organization barriers.

  15. Pacific salmonines in the Great Lakes Basin

    Science.gov (United States)

    Claramunt, Randall M.; Madenjian, Charles P.; Clapp, David; Taylor, William W.; Lynch, Abigail J.; Léonard, Nancy J.

    2012-01-01

    Pacific salmon (genus Oncorhynchus) are a valuable resource, both within their native range in the North Pacific rim and in the Great Lakes basin. Understanding their value from a biological and economic perspective in the Great Lakes, however, requires an understanding of changes in the ecosystem and of management actions that have been taken to promote system stability, integrity, and sustainable fisheries. Pacific salmonine introductions to the Great Lakes are comprised mainly of Chinook salmon, coho salmon, and steelhead and have accounted for 421, 177, and 247 million fish, respectively, stocked during 1966-2007. Stocking of Pacific salmonines has been effective in substantially reducing exotic prey fish abundances in several of the Great Lakes (e.g., lakes Michigan, Huron, and Ontario). The goal of our evaluation was to highlight differences in management strategies and perspectives across the basin, and to evaluate policies for Pacific salmonine management in the Great Lakes. Currently, a potential conflict exists between Pacific salmonine management and native fish rehabilitation goals because of the desire to sustain recreational fisheries and to develop self-sustaining populations of stocked Pacific salmonines in the Great Lakes. We provide evidence that suggests Pacific salmonines have not only become naturalized to the food webs of the Great Lakes, but that their populations (specifically Chinook salmon) may be fluctuating in concert with specific prey (i.e., alewives) whose populations are changing relative to environmental conditions and ecosystem disturbances. Remaining questions, however, are whether or not “natural” fluctuations in predator and prey provide enough “stability” in the Great Lakes food webs, and even more importantly, would a choice by managers to attempt to reduce the severity of predator-prey oscillations be antagonistic to native fish restoration efforts. We argue that, on each of the Great Lakes, managers are pursuing

  16. [Blood-brain barrier part III: therapeutic approaches to cross the blood-brain barrier and target the brain].

    Science.gov (United States)

    Weiss, N; Miller, F; Cazaubon, S; Couraud, P-O

    2010-03-01

    Over the last few years, the blood-brain barrier has come to be considered as the main limitation for the treatment of neurological diseases caused by inflammatory, tumor or neurodegenerative disorders. In the blood-brain barrier, the close intercellular contact between cerebral endothelial cells due to tight junctions prevents the passive diffusion of hydrophilic components from the bloodstream into the brain. Several specific transport systems (via transporters expressed on cerebral endothelial cells) are implicated in the delivery of nutriments, ions and vitamins to the brain; other transporters expressed on cerebral endothelial cells extrude endogenous substances or xenobiotics, which have crossed the cerebral endothelium, out of the brain and into the bloodstream. Recently, several strategies have been proposed to target the brain, (i) by by-passing the blood-brain barrier by central drug administration, (ii) by increasing permeability of the blood-brain barrier, (iii) by modulating the expression and/or the activity of efflux transporters, (iv) by using the physiological receptor-dependent blood-brain barrier transport, and (v) by creating new viral or chemical vectors to cross the blood-brain barrier. This review focuses on the illustration of these different approaches. Copyright (c) 2009 Elsevier Masson SAS. All rights reserved.

  17. Great Lakes Restoration Initiative Great Lakes Mussel Watch(2009-2014)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Following the inception of the Great Lakes Restoration Initiative (GLRI) to address the significant environmental issues plaguing the Great Lakes region, the...

  18. Tunnelling without barriers

    International Nuclear Information System (INIS)

    Lee, K.

    1987-01-01

    The evolution in flat and curved space-time of quantum fields in theories with relative flat potential and its consequences are considered. It is shown that bubble nucleation, a quantum mechanical tunnelling process, may occur in flat space-time, having a bounce solution, even if V(phi) has no barrier. It is shown that bubble nucleation can also occur in curved space-time even though there is no bounce solution in the standard formalism for the bubble nucleation rate in curved space-time. Additionally, bubbles can nucleate during the slow rolling period on the potential in flat and curved space-time, in this case also there is no bounce solution. It is known in the new inflationary scenario that energy density perturbations caused by quantum fluctuations of the scalar field can satisfy the presently observed bounds on density perturbations. Bubble nucleation during the slow rolling period also gives rise to density perturbations. For a model potential density perturbations by bubbles are calculated at the horizon reentering. By applying the bound from the almost isotropic microwave black body radiation on these density perturbations, a constraint on the model potential is obtained. Finally, some further implications on the galaxy formation and applications in more realistic potential are discussed

  19. Development of engineered barrier

    Energy Technology Data Exchange (ETDEWEB)

    Chun, Kwan Sik; Cho, Won Jin; Lee, Jae Owan; Kim, Seung Soo; Kang, Mu Ja

    1999-03-01

    Engineered barrier development was carried out into the three research fields : waste form, disposal container, and buffer. The waste form field dealt with long-term leaching tests with borosilicate waste glasses surrounded by compacted bentonite. The leach rate decreased with increasing time, and was higher for the waste specimen rich in U and Na. In the container field, preliminary concepts of disposal containers were recommended by conducting structural analysis, thermal analysis, and shielding analysis, and major properties of stainless steel, copper, and titanium as a container material were surveyed. The sensitization degrees of SUS 316 and316L were lower than those of SUS 304 and 304L, respectively. The crevice corrosion of sensitized stainless steel was sensitive to the content of salt. Researches into the buffer included establishment of its performance criteria followed by investigating major properties of buffer using potential material in Korea. Experiments were made for measuring hydraulic conductivities, swelling properties, mechanical properties, thermal conductivities, pore-water chemistry properties, and adsorption properties was also investigated. (author)

  20. Alternative geochemical barrier materials

    International Nuclear Information System (INIS)

    1991-07-01

    Previous investigations of the effects of neutralization and reduction on uranium mill tailings pore fluids by the Technical Support Contractor indicated that arsenic, selenium, and molybdenum continue to remain in solution in all but reducing conditions. These hazardous constituents are present in groundwaters as oxyanions and, therefore, are not expected to be removed by adsorption into clays and most other soil constituents. It was decided to investigate the attenuation capacity of two commonly available crystalline iron oxides, taconite and scoria, and a zeolite, a network aluminosilicate with a cage structure. Columns of the candidate materials were exposed to solutions of individual constituents, including arsenic, molybdenum, selenium, and, uranium, and to the spiked tailings pore fluid from the Bodo Canyon disposal cell near Durango, Colorado. In addition to the single material columns, a homogeneous blend of the three materials and layers of the materials were exposed to spiked tailings pore fluids. The results of these experiments indicate that with the exception of molybdenum, the constituents of concern are attenuated by the taconite; however, they are not sufficiently attenuated to meet the groundwater protection standards applicable to the UMTRA Project. Therefore, the candidate barrier materials did not prove to be useful to the UMTRA Project for the cleanup of groundwaters

  1. Mobilitet, barrierer & muligheder

    DEFF Research Database (Denmark)

    Petersen, Mimi

    2011-01-01

    stereotypering. På den ene side peger udsagn fra de unge drenge på en oplevelse af at blive kriminaliseret i kraft af deres køn (det maskuline kombineret med at have en anden hudfarve). Og de unge piger oplever, at de udover at blive kategoriseret som ”indvandrere” også bliver kategoriseret som passive, umyndige...... som en vej ud af irakiske Kurdistan, men ikke tilbage til Danmark. Drengene fra familier med bedre økonomiske ressourcer giver udtryk for, ønske om at rejse til andre lande. På grund af begrænsede sproglige kompetencer oplever hovedparten af de unge (både i Danmark og i irakiske Kurdistan) barrierer i...... har planer for at flytte fra Kurdistan. De har dansk statsborgerskab, men de vil ikke tilbage til Danmark. I de fortællinger, som afhandlingen bygger på, er det tydeligt at samspillet mellem flere sociale dimensioner, spiller ind på de unges selvforståelse, tilhørsforhold, erfaringer og deres valg af...

  2. Development of engineered barrier

    International Nuclear Information System (INIS)

    Chun, Kwan Sik; Cho, Won Jin; Lee, Jae Owan; Kim, Seung Soo; Kang, Mu Ja

    1999-03-01

    Engineered barrier development was carried out into the three research fields : waste form, disposal container, and buffer. The waste form field dealt with long-term leaching tests with borosilicate waste glasses surrounded by compacted bentonite. The leach rate decreased with increasing time, and was higher for the waste specimen rich in U and Na. In the container field, preliminary concepts of disposal containers were recommended by conducting structural analysis, thermal analysis, and shielding analysis, and major properties of stainless steel, copper, and titanium as a container material were surveyed. The sensitization degrees of SUS 316 and 316L were lower than those of SUS 304 and 304L, respectively. The crevice corrosion of sensitized stainless steel was sensitive to the content of salt. Researches into the buffer included establishment of its performance criteria followed by investigating major properties of buffer using potential material in Korea. Experiments were made for measuring hydraulic conductivities, swelling properties, mechanical properties, thermal conductivities, pore-water chemistry properties, and adsorption properties was also investigated. (author)

  3. Central Nervous System Vasculitis

    Science.gov (United States)

    ... of Vasculitis / Central Nervous System (CNS) Vasculitis Central Nervous System (CNS) Vasculitis Swap out your current Facebook Profile ... Facebook personal page. Replace with this image. Central nervous system (CNS) vasculitis is inflammation of blood vessel walls ...

  4. Boundaries of Welfare between the EU and Member States during the ‘Great Recession’

    DEFF Research Database (Denmark)

    de la Porte, Caroline; Pochet, Philippe

    2014-01-01

    -state reform changes over time in line with socio-economic conditions as well as shifting political-party governmental coalitions in the Council. We argue that in particular the economically oriented actors, including the European Central Bank, have been successful in the context of the Great Recession. More...... recently, social priorities around notions such as social investment are becoming more central in the EU debate on economic and social policy....

  5. Conceptual Barriers to Progress Within Evolutionary Biology.

    Science.gov (United States)

    Laland, Kevin N; Odling-Smee, John; Feldman, Marcus W; Kendal, Jeremy

    2009-08-01

    In spite of its success, Neo-Darwinism is faced with major conceptual barriers to further progress, deriving directly from its metaphysical foundations. Most importantly, neo-Darwinism fails to recognize a fundamental cause of evolutionary change, "niche construction". This failure restricts the generality of evolutionary theory, and introduces inaccuracies. It also hinders the integration of evolutionary biology with neighbouring disciplines, including ecosystem ecology, developmental biology, and the human sciences. Ecology is forced to become a divided discipline, developmental biology is stubbornly difficult to reconcile with evolutionary theory, and the majority of biologists and social scientists are still unhappy with evolutionary accounts of human behaviour. The incorporation of niche construction as both a cause and a product of evolution removes these disciplinary boundaries while greatly generalizing the explanatory power of evolutionary theory.

  6. Weaning stress and gastrointestinal barrier development: Implications for lifelong gut health in pigs

    Directory of Open Access Journals (Sweden)

    Adam J. Moeser

    2017-12-01

    Full Text Available The gastrointestinal (GI barrier serves a critical role in survival and overall health of animals and humans. Several layers of barrier defense mechanisms are provided by the epithelial, immune and enteric nervous systems. Together they act in concert to control normal gut functions (e.g., digestion, absorption, secretion, immunity, etc. whereas at the same time provide a barrier from the hostile conditions in the luminal environment. Breakdown of these critical GI functions is a central pathophysiological mechanism in the most serious GI disorders in pigs. This review will focus on the development and functional properties of the GI barrier in pigs and how common early life production stressors, such as weaning, can alter immediate and long-term barrier function and disease susceptibility. Specific stress-related pathophysiological mechanisms responsible for driving GI barrier dysfunction induced by weaning and the implications to animal health and performance will be discussed.

  7. 75 FR 6354 - NOAA Great Lakes Habitat Restoration Program Project Grants under the Great Lakes Restoration...

    Science.gov (United States)

    2010-02-09

    ...-04] RIN 0648-ZC10 NOAA Great Lakes Habitat Restoration Program Project Grants under the Great Lakes... Atmospheric Administration (NOAA), Department of Commerce. ACTION: Notice of funding availability; Date... on January 19, 2010. That notice announced the NOAA Great Lakes Habitat Restoration Program Project...

  8. Selection of design parameters of diffusion barrier in a passive 222Rn sampler based on activated charcoal adsorption

    International Nuclear Information System (INIS)

    Wei Suxia

    1992-01-01

    A method concerning selection of design parameters of diffusion barrier in a passive 222 Rn sampler based on activated charcoal adsorption. The proper parameter value of diffusion barrier is obtained by means of linearization of 222 Rn adsorption versus the exposure time. Thus, the influence of temperature on measured results may be greatly decreased, and higher sensitivity of the detector may be maintained

  9. Thermal barrier coatings application in diesel engines

    Science.gov (United States)

    Fairbanks, J. W.

    1995-01-01

    Commercial use of thermal barrier coatings in diesel engines began in the mid 70's by Dr. Ingard Kvernes at the Central Institute for Industrial Research in Oslo, Norway. Dr. Kvernes attributed attack on diesel engine valves and piston crowns encountered in marine diesel engines in Norwegian ships as hot-corrosion attributed to a reduced quality of residual fuel. His solution was to coat these components to reduce metal temperature below the threshold of aggressive hot-corrosion and also provide protection. Roy Kamo introduced thermal barrier coatings in his 'Adiabatic Diesel Engine' in the late 70's. Kamo's concept was to eliminate the engine block water cooling system and reduce heat losses. Roy reported significant performance improvements in his thermally insulated engine at the SAE Congress in 1982. Kamo's work stimulates major programs with insulated engines, particularly in Europe. Most of the major diesel engine manufacturers conducted some level of test with insulated combustion chamber components. They initially ran into increased fuel consumption. The German engine consortium had Prof. Woschni of the Technical Institute in Munich. Woschni conducted testing with pistons with air gaps to provide the insulation effects. Woschni indicated the hot walls of the insulated engine created a major increase in heat transfer he refers to as 'convection vive.' Woschni's work was a major factor in the abrupt curtailment of insulated diesel engine work in continental Europe. Ricardo in the UK suggested that combustion should be reoptimized for the hot-wall effects of the insulated combustion chamber and showed under a narrow range of conditions fuel economy could be improved. The Department of Energy has supported thermal barrier coating development for diesel engine applications. In the Clean Diesel - 50 Percent Efficient (CD-50) engine for the year 2000, thermal barrier coatings will be used on piston crowns and possibly other components. The primary purpose of the

  10. The Great Recession and confidence in homeownership

    OpenAIRE

    Anat Bracha; Julian Jamison

    2013-01-01

    Confidence in homeownership shifts for those who personally experienced real estate loss during the Great Recession. Older Americans are confident in the value of homeownership. Younger Americans are less confident.

  11. Great Lakes CoastWatch Node

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — CoastWatch is a nationwide National Oceanic and Atmospheric Administration (NOAA) program within which the Great Lakes Environmental Research Laboratory (GLERL)...

  12. The Making of a Great Captain

    National Research Council Canada - National Science Library

    Weibel, Theodore G

    2006-01-01

    ... judgement. This paper examines the hypothesis that Great Captains are a product of their families, are highly educated from an early age, possess the qualities of a genius, encounter grand life experiences...

  13. Thirty years of great ape gestures.

    Science.gov (United States)

    Tomasello, Michael; Call, Josep

    2018-02-21

    We and our colleagues have been doing studies of great ape gestural communication for more than 30 years. Here we attempt to spell out what we have learned. Some aspects of the process have been reliably established by multiple researchers, for example, its intentional structure and its sensitivity to the attentional state of the recipient. Other aspects are more controversial. We argue here that it is a mistake to assimilate great ape gestures to the species-typical displays of other mammals by claiming that they are fixed action patterns, as there are many differences, including the use of attention-getters. It is also a mistake, we argue, to assimilate great ape gestures to human gestures by claiming that they are used referentially and declaratively in a human-like manner, as apes' "pointing" gesture has many limitations and they do not gesture iconically. Great ape gestures constitute a unique form of primate communication with their own unique qualities.

  14. Southern Great Plains Atmospheric Radiation Measurement Site

    Data.gov (United States)

    Federal Laboratory Consortium — The Southern Great Plains Atmospheric Radiation Measurement Site (SGP-ARM) is the oldest and largest of DOE's Arm sites. It was established in 1992. It consists of...

  15. Theodosius Dohzhansky: A Great Inspirer 1

    Indian Academy of Sciences (India)

    the direct personal influence of some of these great scientists on their peers and successors is re~atively small. A very small number of scientists ... studying the evolutionary genetics of speciation in Drosophila. --------~--------43. RESONANCE I ...

  16. Great Lakes rivermouths: a primer for managers

    Science.gov (United States)

    Pebbles, Victoria; Larson, James; Seelbach, Paul; Pebbles, Victoria; Larson, James; Seelbach, Paul

    2013-01-01

    Between the North American Great Lakes and their tributaries are the places where the confluence of river and lake waters creates a distinct ecosystem: the rivermouth ecosystem. Human development has often centered around these rivermouths, in part, because they provide a rich array of ecosystem services. Not surprisingly, centuries of intense human activity have led to substantial pressures on, and alterations to, these ecosystems, often diminishing or degrading their ecological functions and associated ecological services. Many Great Lakes rivermouths are the focus of intense restoration efforts. For example, 36 of the active Great Lakes Areas of Concern (AOCs) are rivermouths or areas that include one or more rivermouths. Historically, research of rivermouth ecosystems has been piecemeal, focused on the Great Lakes proper or on the upper reaches of tributaries, with little direct study of the rivermouth itself. Researchers have been divided among disciplines, agencies and institutions; and they often work independently and use disparate venues to communicate their work. Management has also been fragmented with a focus on smaller, localized, sub-habitat units and socio-political or economic elements, rather than system-level consideration. This Primer presents the case for a more holistic approach to rivermouth science and management that can enable restoration of ecosystem services with multiple benefits to humans and the Great Lakes ecosystem. A conceptual model is presented with supporting text that describes the structures and processes common to all rivermouths, substantiating the case for treating these ecosystems as an identifiable class.1 Ecological services provided by rivermouths and changes in how humans value those services over time are illustrated through case studies of two Great Lakes rivermouths—the St. Louis River and the Maumee River. Specific ecosystem services are identified in italics throughout this Primer and follow definitions described

  17. Expectations of barriers to psychosocial care: views of parents and adolescents in the community.

    Science.gov (United States)

    Nanninga, Marieke; Reijneveld, Sijmen A; Knorth, Erik J; Jansen, Danielle E M C

    2016-01-01

    Parents with a child suffering from psychosocial problems frequently experience barriers to psychosocial care, which may hinder access. Expectations of barriers may have the same effect, but evidence is lacking. The aim of this study is to examine parents' and adolescents' expectations of barriers regarding psychosocial care for the child, along with associated child and family characteristics. We obtained data on an age-stratified random sample of school children/pupils aged 4-18 via questionnaires (N = 666; response rate 70.3 %). Expectations of barriers to psychosocial care were measured with the "Barriers to Treatment Participation Scale-Expectancies" questionnaire (BTPS-exp). Results showed that 64 % of the parents of children below age 12, 59 % of the parents of adolescents (age 12-18), and 84 % of the adolescents expected one or more barriers. Parents and adolescents expected barriers most frequently with respect to irrelevance of treatment. Mainly parents with low educational level and their adolescents expected barriers regarding treatment, and quite a few characteristics of parents of adolescents were associated with expecting multiple barriers regarding treatment demands and issues, for example, single parents, parents of lower educational level and of adolescent boys, and parents of adolescents with psychosocial problems. We conclude that adolescents especially, but also their parents and parents of younger children, expect major barriers to psychosocial care, which may greatly hinder appropriate care seeking. This evidence may support professionals and policymakers in their attempts to improve access to psychosocial care.

  18. Understanding Great Earthquakes in Japan's Kanto Region

    Science.gov (United States)

    Kobayashi, Reiji; Curewitz, Daniel

    2008-10-01

    Third International Workshop on the Kanto Asperity Project; Chiba, Japan, 16-19 February 2008; The 1703 (Genroku) and 1923 (Taisho) earthquakes in Japan's Kanto region (M 8.2 and M 7.9, respectively) caused severe damage in the Tokyo metropolitan area. These great earthquakes occurred along the Sagami Trough, where the Philippine Sea slab is subducting beneath Japan. Historical records, paleoseismological research, and geophysical/geodetic monitoring in the region indicate that such great earthquakes will repeat in the future.

  19. The diverse impacts of the great recession

    OpenAIRE

    Makoto Nakajima

    2013-01-01

    The Great Recession had a large negative impact on the U.S. economy. Asset prices, most notably stock and house prices, declined substantially, resulting in a loss in wealth for many American households. In this article, Makoto Nakajima documents how diverse households were affected in a variety of dimensions during the Great Recession, in particular between 2007 and 2009, using newly available data from the 2007-2009 Survey of Consumer Finances. He discusses why it is important to look at th...

  20. The Great War and German Memory

    DEFF Research Database (Denmark)

    Leese, Peter

    2012-01-01

    Review essay on Jason Crouthamel, The Great War and German Memory. Society, Politics and Psychological Trauma, 1914-18 (2009) and Anton Kaes, Shell Shock Cinema: Weimar Culture and the Wounds of War (2009)......Review essay on Jason Crouthamel, The Great War and German Memory. Society, Politics and Psychological Trauma, 1914-18 (2009) and Anton Kaes, Shell Shock Cinema: Weimar Culture and the Wounds of War (2009)...

  1. Financing environmental policy in East Central Europe

    NARCIS (Netherlands)

    Kolk, A.; van der Weij, E.

    1998-01-01

    The transition in East Central Europe created a general optimism which was reflected in a belief that a solution to the environmental problems faced by these countries would be found. There were great expectations regarding the blessings of the market economy, which would diminish state-guided waste

  2. Non-surgical retreatment of a failed apicoectomy without retrofilling using white mineral trioxide aggregate as an apical barrier.

    Science.gov (United States)

    Stefopoulos, Spyridon; Tzanetakis, Giorgos N; Kontakiotis, Evangelos G

    2012-01-01

    Root-end resected teeth with persistent apical periodontitis are usually retreated surgically or a combination of non-surgical and surgical retreatment is employed. However, patients are sometimes unwilling to be subjected to a second surgical procedure. The apical barrier technique that is used for apical closure of immature teeth with necrotic pulps may be an alternative to non-surgically retreat a failed apicoectomy. Mineral trioxide aggregate (MTA) has become the material of choice in such cases because of its excellent biocompatibility, sealing ability and osseoinductive properties. This case report describes the non-surgical retreatment of a failed apicoectomy with no attempt at retrofilling of a maxillary central incisor. White MTA was used to induce apical closure of the wide resected apical area. Four-year follow-up examination revealed an asymptomatic, fully functional tooth with a satisfactory healing of the apical lesion. White MTA apical barrier may constitute a reliable and efficient technique to non-surgically retreat teeth with failed root-end resection. The predictability of such a treatment is of great benefit for the patient who is unwilling to be submitted to a second surgical procedure.

  3. Implementation of a Non-Metallic Barrier in an Electric Motor

    Science.gov (United States)

    M?Sadoques, George; Carra, Michael; Beringer, Woody

    2012-01-01

    Electric motors that run in pure oxygen must be sealed, or "canned," for safety reasons to prevent the oxygen from entering into the electrical portion of the motor. The current canning process involves designing a metallic barrier around the rotor to provide the separation. This metallic barrier reduces the motor efficiency as speed is increased. In higher-speed electric motors, efficiency is greatly improved if a very thin, nonmetallic barrier can be utilized. The barrier thickness needs to be approximately 0.025-in. (.0.6-mm) thick and can be made of a brittle material such as glass. The motors, however, designed for space applications are typically subject to high-vibration environments. A fragile, non-metallic barrier can be utilized in a motor assembly if held in place by a set of standard rubber O-ring seals. The O-rings provide the necessary sealing to keep oxygen away from the electrical portion of the motor and also isolate the fragile barrier from the harsh motor vibration environment. The compliance of the rubber O-rings gently constrains the fragile barrier and isolates it from the harsh external motor environment. The use of a non-metallic barrier greatly improves motor performance, especially at higher speeds, while isolating the electronics from the working fluid with an inert liner.

  4. Climate variability and Great Plains agriculture

    International Nuclear Information System (INIS)

    Rosenberg, N.J.; Katz, L.A.

    1991-01-01

    The ways in which inhabitants of the Great Plains, including Indians, early settlers, and 20th century farmers, have adapted to climate changes on the Great Plains are explored. The climate of the Great Plains, because of its variability and extremes, can be very stressful to plants, animals and people. It is suggested that agriculture and society on the Great Plains have, during the last century, become less vulnerable to the stresses imposed by climate. Opinions as to the sustainability of agriculture on the Great Plains vary substantially. Lockeretz (1981) suggests that large scale, high cost technologies have stressed farmers by creating surpluses and by requiring large investments. Opie (1989) sees irrigation as a climate substitute, however he stresses that the Ogallala aquifer must inevitably become depleted. Deborah and Frank Popper (1987) believe that farming on the Plains is unsustainable, and destruction of shelterbelts, out-migration of the rural population and environmental problems will lead to total collapse. With global warming, water in the Great Plains is expected to become scarcer, and although improvements in irrigation efficiency may slow depletion of the Ogallala aquifer, ultimately the acreage under irrigation must decrease to levels that can be sustained by natural recharge and reliable surface flows. 23 refs., 2 figs

  5. Tritium/hydrogen barrier development

    International Nuclear Information System (INIS)

    Hollenberg, G.W.; Simonen, E.P.; Kalinen, G.; Terlain, A.

    1994-06-01

    A review of hydrogen permeation barriers that can be applied to structural metals used in fusion power plants is presented. Both implanted and chemically available hydrogen isotopes must be controlled in fusion plants. The need for permeation barriers appears strongest in Li17-Pb blanket designs, although barriers also appear necessary for other blanket and coolant systems. Barriers that provide greater than a 1000 fold reduction in the permeation of structural metals are desired. In laboratory experiments, aluminide and titanium ceramic coatings provide permeation reduction factors, PRFS, from 1000 to over 100,000 with a wide range of scatter. The rate-controlling mechanism for hydrogen permeation through these barriers may be related to the number and type of defects in the barriers. Although these barriers appear robust and resistant to liquid metal corrosion, irradiation tests which simulate blanket environments result in very low PRFs in comparison to laboratory experiments, i.e., <150. It is anticipated from fundamental research activities that the REID enhancement of hydrogen diffusion in oxides may contribute to the lower permeation reduction factors during in-reactor experiments

  6. Enershield : energy saving air barriers

    Energy Technology Data Exchange (ETDEWEB)

    Hallihan, D. [Enershield Industries Ltd., Edmonton, AB (Canada)

    2008-07-01

    Enershield Industries is a leader in air barrier technology and provides solution for the Canadian climate. This presentation described the advantages of air barriers and the impact of rising energy costs. An air barrier is used to separate areas of differing environments and makes existing building systems more efficient. This presentation discussed how an air barrier works. It also identified how Enershield Industries calculates energy savings. It described air barrier applications and those who use barrier technology. These include the commercial and industrial sector as well as the personnel and retail sector. Barrier technology can be used for cold storage; vehicle and equipment washes; food processing; and environmental separation. Features and benefits such as the ability to create seal, acoustic insulation, and long term durability were also discussed. Last, the presentation addressed model selection and design criteria issues. Design criteria that were presented included a discussion of acoustic installation, articulating nozzles, scroll cased fans, and structural frame. Other design criteria presented were galvanized frames, telescopic sliders, and off the shelf parts. It was concluded that the ability to reduce energy consumption and enhance employee/client comfort is beneficial to the employer as well as to the employee. figs.

  7. Compsopogon cf. coeruleus, a benthic red alga (Rhodophyta) new to the Laurentian Great Lakes

    Science.gov (United States)

    Manny, Bruce A.; Edsall, Thomas A.; Wujek, Daniel E.

    1991-01-01

    We found Compsopogon cf. coeruleus for the first time in the Laurentian Great Lakes, growing on limestone rocks at a depth of 21 m on Six Fathom Bank in central Lake Huron. It is the first freshwater red alga to be found in the Great Lakes and the only red alga ever found on an offshore reef in the Great Lakes. However, because this alga usually inhabits water 10–28 °C and has not survived freezing winter temperatures elsewhere, it may not be a permanent member of the flora.

  8. Penetration through the Skin Barrier

    DEFF Research Database (Denmark)

    Nielsen, Jesper Bo; Benfeldt, Eva; Holmgaard, Rikke

    2016-01-01

    The skin is a strong and flexible organ with barrier properties essential for maintaining homeostasis and thereby human life. Characterizing this barrier is the ability to prevent some chemicals from crossing the barrier while allowing others, including medicinal products, to pass at varying rates......-through diffusion cells) as well as in vivo methods (microdialysis and microperfusion). Then follows a discussion with examples of how different characteristics of the skin (age, site and integrity) and of the penetrants (size, solubility, ionization, logPow and vehicles) affect the kinetics of percutaneous...

  9. Vehicle barrier with access delay

    Science.gov (United States)

    Swahlan, David J; Wilke, Jason

    2013-09-03

    An access delay vehicle barrier for stopping unauthorized entry into secure areas by a vehicle ramming attack includes access delay features for preventing and/or delaying an adversary from defeating or compromising the barrier. A horizontally deployed barrier member can include an exterior steel casing, an interior steel reinforcing member and access delay members disposed within the casing and between the casing and the interior reinforcing member. Access delay members can include wooden structural lumber, concrete and/or polymeric members that in combination with the exterior casing and interior reinforcing member act cooperatively to impair an adversarial attach by thermal, mechanical and/or explosive tools.

  10. Big Data as Information Barrier

    Directory of Open Access Journals (Sweden)

    Victor Ya. Tsvetkov

    2014-07-01

    Full Text Available The article covers analysis of ‘Big Data’ which has been discussed over last 10 years. The reasons and factors for the issue are revealed. It has proved that the factors creating ‘Big Data’ issue has existed for quite a long time, and from time to time, would cause the informational barriers. Such barriers were successfully overcome through the science and technologies. The conducted analysis refers the “Big Data” issue to a form of informative barrier. This issue may be solved correctly and encourages development of scientific and calculating methods.

  11. Internal Transport Barrier Driven by Redistribution of Energetic Ions

    International Nuclear Information System (INIS)

    Wong, K.L.; Heidbrink, W.W.; Ruskov, E.; Petty, C.C.; Greenfield, C.M.; Nazikian, R.; Budny, R.

    2004-01-01

    Alfven instabilities excited by energetic ions are used as a means to reduce the central magnetic shear in a tokamak via redistribution of energetic ions. When the central magnetic shear is low enough, ballooning modes become stable for any plasma pressure gradient and an internal transport barrier (ITB) with a steep pressure gradient can exist. This mechanism can sustain a steady-state ITB as demonstrated by experimental data from the DIII-D tokamak. It can also produce a shear in toroidal and poloidal plasma rotation. Possible application of this technique to use the energetic alpha particles for improvement of burning plasma performance is discussed

  12. Mine flooding and barrier pillar hydrology in the Pittsburgh basin

    International Nuclear Information System (INIS)

    Leavitt, B.R.

    1999-01-01

    Pennsylvania began requiring barrier pillars between mines as early as 1930. The Ashley formula, resulting from a early commission on the problem, requires 20 feet of coal plus a thickness of coal equal to four times the seam height plus an additional thickness of coal equal to one tenth of the overburden thickness, or the maximum potential hydraulic head. For a 6-foot thick coal seam under 400 feet of cover, the barrier would be 20+24+40=84 feet. The Ashley formula is intended to protect coal miners from a catastrophic failure of a barrier pillar which has a high head of water impounded behind it. The paper gives several examples of flooded and unflooded mines and the performance of their barrier pillars with respect to acid mine drainage. It is concluded that for all practical purposes, barrier pillars designed with the Ashley formula are able to hydrologically isolate mines from one another. This hydrologic isolation promotes the inundation of closed mines. Inundation effectively stops acid formation, thus, fully inundated mines do not represent a perpetual source of acid mine drainage. Infiltrating ground water improves the mine water chemistry resulting in a net alkaline discharge which has greatly lowered iron concentrations. The best locations for acid mine drainage treatment plants is at the lowest surface elevation above the mine with mine flooded to near that elevation

  13. Nanoscale stiffness topography reveals structure and mechanics of the transport barrier in intact nuclear pore complexes

    Science.gov (United States)

    Bestembayeva, Aizhan; Kramer, Armin; Labokha, Aksana A.; Osmanović, Dino; Liashkovich, Ivan; Orlova, Elena V.; Ford, Ian J.; Charras, Guillaume; Fassati, Ariberto; Hoogenboom, Bart W.

    2015-01-01

    The nuclear pore complex (NPC) is the gate for transport between the cell nucleus and the cytoplasm. Small molecules cross the NPC by passive diffusion, but molecules larger than ∼5 nm must bind to nuclear transport receptors to overcome a selective barrier within the NPC. Although the structure and shape of the cytoplasmic ring of the NPC are relatively well characterized, the selective barrier is situated deep within the central channel of the NPC and depends critically on unstructured nuclear pore proteins, and is therefore not well understood. Here, we show that stiffness topography with sharp atomic force microscopy tips can generate nanoscale cross-sections of the NPC. The cross-sections reveal two distinct structures, a cytoplasmic ring and a central plug structure, which are consistent with the three-dimensional NPC structure derived from electron microscopy. The central plug persists after reactivation of the transport cycle and resultant cargo release, indicating that the plug is an intrinsic part of the NPC barrier. Added nuclear transport receptors accumulate on the intact transport barrier and lead to a homogenization of the barrier stiffness. The observed nanomechanical properties in the NPC indicate the presence of a cohesive barrier to transport and are quantitatively consistent with the presence of a central condensate of nuclear pore proteins in the NPC channel.

  14. Energy and water in the Great Lakes.

    Energy Technology Data Exchange (ETDEWEB)

    Tidwell, Vincent Carroll

    2011-11-01

    The nexus between thermoelectric power production and water use is not uniform across the U.S., but rather differs according to regional physiography, demography, power plant fleet composition, and the transmission network. That is, in some regions water demand for thermoelectric production is relatively small while in other regions it represents the dominate use. The later is the case for the Great Lakes region, which has important implications for the water resources and aquatic ecology of the Great Lakes watershed. This is today, but what about the future? Projected demographic trends, shifting lifestyles, and economic growth coupled with the threat of global climate change and mounting pressure for greater U.S. energy security could have profound effects on the region's energy future. Planning for such an uncertain future is further complicated by the fact that energy and environmental planning and regulatory decisionmaking is largely bifurcated in the region, with environmental and water resource concerns generally taken into account after new energy facilities and technologies have been proposed, or practices are already in place. Based on these confounding needs, the objective of this effort is to develop Great Lakes-specific methods and tools to integrate energy and water resource planning and thereby support the dual goals of smarter energy planning and development, and protection of Great Lakes water resources. Guiding policies for this planning are the Great Lakes and St. Lawrence River Basin Water Resources Compact and the Great Lakes Water Quality Agreement. The desired outcome of integrated energy-water-aquatic resource planning is a more sustainable regional energy mix for the Great Lakes basin ecosystem.

  15. Reproduction Patterns of Scleractinian Corals in the Central Red Sea

    KAUST Repository

    Bouwmeester, Jessica

    2013-12-01

    Early work on the reproductive seasonality of corals in the Red Sea suggested that corals exhibit temporal reproductive isolation, unlike on the Great Barrier Reef where many species spawn in synchrony. More recent work has however shown high synchrony in the maturity of gametes in Acropora species, suggesting multi-specific spawning is likely to occur in the Red Sea. In this thesis I investigate the patterns of coral reproduction in the central Red Sea. The spawning season in the central Red Sea lasts four months, from April to July and spawning occurs on nights around the full moon. During this period Acropora species show a peak of spawning in April, with some species spawning again in May. The level of synchrony, quantified with a spawning synchrony index, is comparable to other locations where multi-specific spawning has been reported. Observations over two consecutive years show that the synchrony of spawning was lower in spring 2012 than in spring 2011, and thus that spawning patterns are variable from one year to the other. Coral settlement patterns on artificial substrata confirmed a main spawning season in the spring but also supported reproductive data suggesting that some Porites spawn in October-November. Settlement was studied over 2.5 years on a reef, which had suffered recently from high mortality after a local bleaching event. Settlement appeared low but post-bleaching studies from other locations indicated similar abundances and showed that recruits generally did not increase until 5 years after the bleaching event. Abundance of juvenile corals however started to increase significantly three years after the bleaching. Successful recruitment, although low suggests that the coral assemblage on the affected reef will most likely recover as long as it is not affected by another disturbance.

  16. [Study on A White-Eye Pattern in Dielectric Barrier Discharge by Optical Emission Spectrum].

    Science.gov (United States)

    Zhu, Ping; Dong, Li-fang; Yang, Jing; Zhang, Yu; Zhang, Chao

    2015-06-01

    is found that the molecular vibration temperature, electron excitation temperature and electronic density of the central spot are lowest, and the plasma parameters of the ambient spots are second, while the plasma parameters of the halo are highest at the same condition. The molecular vibration temperature and the electron excitation temperature of the three different parts of the pattern (central spot, halo, and ambient spots) decrease with the pressure increasing from 40 to 60 kPa, but the electronic density increases. These results are of great important to the formation mechanism of the patterns in dielectric barrier discharge.

  17. The oceanic sediment barrier

    International Nuclear Information System (INIS)

    Francis, T.J.G.; Searle, R.C.; Wilson, T.R.S.

    1986-01-01

    Burial within the sediments of the deep ocean floor is one of the options that have been proposed for the disposal of high-level radioactive waste. An international research programme is in progress to determine whether oceanic sediments have the requisite properties for this purpose. After summarizing the salient features of this programme, the paper focuses on the Great Meteor East study area in the Northeast Atlantic, where most oceanographic effort has been concentrated. The geological geochemical and geotechnical properties of the sediments in the area are discussed. Measurements designed to determine the rate of pore water movement through the sediment column are described. Our understanding of the chemistry of both the solid and pore-water phases of the sediment are outlined, emphasizing the control that redox conditions have on the mobility of, for example, naturally occurring manganese and uranium. The burial of instrumented free-fall penetrators to depths of 30 m beneath the ocean floor is described, modelling one of the methods by which waste might be emplaced. Finally, the nature of this oceanic environment is compared with geological environments on land and attention is drawn to the gaps in our knowledge that must be filled before oceanic burial can be regarded as an acceptable disposal option. (author)

  18. Fusion barrier characteristics of actinides

    Science.gov (United States)

    Manjunatha, H. C.; Sridhar, K. N.

    2018-03-01

    We have studied fusion barrier characteristics of actinide compound nuclei with atomic number range 89 ≤ Z ≤ 103 for all projectile target combinations. After the calculation of fusion barrier heights and positions, we have searched for their parameterization. We have achieved the empirical formula for fusion barrier heights (VB), positions (RB), curvature of the inverted parabola (ħω) of actinide compound nuclei with atomic number range 89 ≤ Z ≤ 103 for all projectile target combinations (6 projectile target combinations. The values produced by the present formula are also compared with experiments. The present pocket formula produces fusion barrier characteristics of actinides with the simple inputs of mass number (A) and atomic number (Z) of projectile-targets.

  19. Transport barrier in Helical system

    International Nuclear Information System (INIS)

    Ida, Katsumi

    1998-01-01

    Experiments on the transport barrier in Helical plasmas are reviewed. There are two mechanisms of transport improvement, that results in the formation of the transport barrier. One is the improvement of neoclassical transport by reducing the ripple loss with radial electric field, which exist only in helical plasma. The other is the improvement of anomalous transport due to the suppression of fluctuations associated with a radial electric field shear both in tokamak and helical plasma. The formation of the transport barrier can be triggered by the radial electric field shear associated with the transition of the radial electric field (L/H transition or ion-electron root transition) or the peaked density or the optimization of magnetic field shear. The mechanisms of transport barrier formation are also discussed. (author). 60 refs

  20. Coastal Structures and Barriers 2012

    Data.gov (United States)

    California Natural Resource Agency — This dataset is a compilation of the UCSC Sand Retention Structures, MC Barriers, and USACE Coastal Structures. UCSC Sand Retention Structures originate from a...