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Sample records for formation beaufort group

  1. Channel sandstone and bar morphology of the Beaufort group uranium district near Beaufort West

    International Nuclear Information System (INIS)

    Stear, W.M.

    1980-01-01

    Sheet-like and lenticular sandstone bodies in the Lower Beaufort Group (Adelaide Subgroup) uranium district occur in megacyclic repetition as superimposed systems of ephemeral fluvial channels that display characteristics of complex lateral and vertical accretion. Channel sandstone bodies are defined on morphological grounds into two types. Sheet sandstone bodies are the commonest type and comprise the bulk of sandstone packages in arenaceous zones of megacycles. Composite sandstone sheets result from multilateral coalescence of individual sandstone bodies. Isolated lenticular sandstone units in argillaceous zones of megacycles comprise sheet and ribbon sandstone types. Multi-storeying is a prominent feature of most channel sandstone bodies and often results in local sandstone thickening. Bedforms relate to the formation of compound bars and record periods of dynamic accretion and erosion. Rarely preserved palaeosurfaces vividly illustrate the fluctuating hydrodynamic conditions that typified ephemeral fluvial sedimentation in a semi-arid environment during Lower Beaufort times

  2. Channel sandstone and bar morphology of the Beaufort group uranium district near Beaufort West

    Energy Technology Data Exchange (ETDEWEB)

    Stear, W M

    1980-01-01

    Sheet-like and lenticular sandstone bodies in the Lower Beaufort Group (Adelaide Subgroup) uranium district occur in megacyclic repetition as superimposed systems of ephemeral fluvial channels that display characteristics of complex lateral and vertical accretion. Channel sandstone bodies are defined on morphological grounds into two types. Sheet sandstone bodies are the commonest type and comprise the bulk of sandstone packages in arenaceous zones of megacycles. Composite sandstone sheets result from multilateral coalescence of individual sandstone bodies. Isolated lenticular sandstone units in argillaceous zones of megacycles comprise sheet and ribbon sandstone types. Multi-storeying is a prominent feature of most channel sandstone bodies and often results in local sandstone thickening. Bedforms relate to the formation of compound bars and record periods of dynamic accretion and erosion. Rarely preserved palaeosurfaces vividly illustrate the fluctuating hydrodynamic conditions that typified ephemeral fluvial sedimentation in a semi-arid environment during Lower Beaufort times.

  3. The sedimentary environment of the Beaufort Group Uranium Province in the vicinity of Beaufort West, South Africa

    International Nuclear Information System (INIS)

    Stear, W.M.

    1980-12-01

    Most of the Beaufort Group uranium deposits in the southwestern Karoo are located near the contact of the Abrahamskraal Formation and the Teekloof Formation within a stratigraphic interval of about 500 meters. Rocks of the Lower Beaufort uranium province in the Beaufort West study area occur in thick, fining upwards megacyclic sequences, each of which consists of an arenaceous zone overlain by an argillaceous zone. The morphology and internal geometry of selected channel sandstone bodies are described in plan and cross-section. Lateral and vertical profile diagrams are used to illustrate the salient features of fluvial style in the Abrahamskraal Formation and to compare these characteristics with recognised fluvial facies models. The Abrahamskraal Formation provides a local facies model of an ancient, interior drainage system characterised by a continuously shifting, ephemeral fluvio-lacustrine complex. Semi-arid climatic conditions in the depositional environment promoted the formation of uranium mineralization. The geologic structure and stratigraphy of the area, the facies and their distribution, the channel facies association as well as the geometry of the channel sandstone bodies and the interchannel facies association are discussed

  4. Beaufort Formation, eastern Axel Heiberg Island, Canadian Arctic Archipelago

    Energy Technology Data Exchange (ETDEWEB)

    Bustin, R.M.

    1982-07-01

    On eastern Axel Heiberg Island erosional outliers of the Miocene-early Pliocene Beaufort Formation overlie with angular unconformity, or are faulted against, Mesozoic and early Tertiary strata East of Princess Margaret Arch the Beaufort Formation is divisible into three lithofacies: a conglomerate lithofacies interpreted as alluvial-plain deposits, a sandstone conglomerate lithofacies interpreted as distal alluvial-fan deposits and a sandstone-mudstone-siltstone lithofacies interpreted as alluvial-plain deposits. The floodplain was vegetated by a coniferous forest which was characterized by Picea banksii, Larix, Metasequoia and Alnus. Paleocurrent analysis, facies relationships and petrology of the conglomerates and sandstones indicate the provenance of the Beaufort Formation wa Mesozoic strata to the west. Deposition of the Beaufort Formation on eastern Axel Heiberg Island clearly postdates folding of mid-Eocene and older strata and thus provides a minimum age for orogenesis in this part of the Arctic. The occurrence of faulted massiv conglomerates of the Beaufort Formation provides evidence for Miocene-early Pliocene or earlier uplift of ancestral Princess Margaret Arch and a still-later phase of extension.

  5. Beaufort group uranium mineralization - a model that may aid exploration

    International Nuclear Information System (INIS)

    Stuart-Williams, V.

    1982-01-01

    The ore bodies examined while working on the Pristerognathus Diictodon Assemblage Zone West of Beaufort West are of the URAVAN type (URA - uranium, VAN - vanadium). It was found that uranium mineralization in any one ore body was not strictly random and tends to be associated with a fairly consistent sandstone and siltstone geometry. Mineralization is only found where coalescence between the two sandstones has occurred and it disappears where the sandstones remain coalesced. At a point of coalescence the fluids from the upper and lower sandstone are mixed, the oxidizing fluid penetrating progressively deeper in the sandstone couplet until the entire couplet is oxidizing. This generates a weakly dipping REDOX front. The REDOX front is not considered strong enough to have precipitated uranyl carbonate complexes in transport

  6. The occurrence, origin and stratigraphic significance of bone-bearing mudstone pellet conglomerates from the Beaufort group in the Jansenville district, Cape Province, South Africa

    International Nuclear Information System (INIS)

    Turner, B.R.

    1981-01-01

    The lack of useful lithostratigraphic markers in the Beaufort Group in the southern Karoo Basin has focused attention on the biostratigraphy of the sediments. As a result a more refined scheme of biostratigraphic classification is now possible which may prove useful in fixing the stratigraphic position of the uranium mineralized horizons. The most important mineralized horizon in the Beaufort West area (contains about 90 per cent of all known uranium occurrences) is associated with the Pristerognathus/Diictodon assemblage zone, but the way in which this relates to the important uranium occurrences farther east, between Graaff-Reinet and Jansenville, is uncertain because of the lack of biostratigraphic control. Vertebrate remains have recently been found in mudstone pellet conglomerates in Beaufort channel sandstones along the Bullrivier in the Jansenville District, in an area that is extensively mineralized. The sandstones were deposited as point bar sands within a meandering river system flowing towards the north-east. The rivers drained a dry, arid to semi-arid alluvial plain and were characterized by fluctuating discharge and periods of low or negligible flow. These conditions promoted flood scour and fill activity and the deposition of internal mudstone pellet conglomerates. Hydrodynamic considerations suggest that estimates of bone transport velocity from their hydrodynamically equivalent quartz sphere is of limited value and can seldom, if ever, be applied to fossil bone accumulations. Identification of the bones from the conglomerates indicates that they belong to the Dino-cephalia biozone and not the overlying Pristerognathus/Diictodon zone. This suggests that the lower part of the Beaufort succession (formerly the Tapinocephalus zone) extends farther east than previously thought, and that the main mineralized horizon in this area occurs lower down in the succession than that around Beaufort West

  7. Beaufort Bridgenet Ichthyoplankton Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Beaufort Bridgenet Ichthyoplankton Sampling Program (BBISP) at the NOAA Beaufort facility is the longest consecutive ichthyoplankton ingress sampling program...

  8. Designing for informed group formation

    DEFF Research Database (Denmark)

    Nicolajsen, Hanne Westh; Juel Jacobsen, Alice; Riis, Marianne

    2012-01-01

    A new design ―project preparation‖ preparing for the group formation in problem based project work is proposed and investigated. The main problem is to overcome group formation based on existing relations. The hypothesis is that theme development and group formation are somewhat counterproductive...

  9. Cross-stratified Wood: Enigmatic Woody Debris Deposits in Warm-Polar Fluvial Sediments (Pliocene Beaufort Formation, Nunavut)

    Science.gov (United States)

    Davies, N. S.; Gosse, J. C.; Rybczynski, N.

    2012-04-01

    Woody debris has been an important sediment component and a significant geomorphic agent in pristine fluvial systems since the Devonian. In recent years a large volume of research has focussed on various aspects of the importance of woody debris within the fluvial realm; from the evolutionary significance of fossil wood accumulations in the rock record to studies of the biogeomorphological and ecological importance of woody debris in modern rivers. In this presentation we describe cross-stratified woody debris deposits comprising organic detritus from a boreal-type treeline forest that included species of pine, birch, poplar, alder, spruce, eastern cedar, and larch, in both shrub and tree form. The cross-stratified wood is an enigmatic subset of fine woody debris which, to our knowledge, has never before been described from either the global stratigraphic record or modern fluvial environments. The deposits we describe are located within the Pliocene Beaufort Formation on Meighen Island, Nunavut, Canada, at a latitude of 80°N, and are compared with other cross-stratified woody debris deposits that have been noted elsewhere in the Pliocene of the Canadian Arctic. We make the robust observation that these deposits appear to be geographically and stratigraphically restricted to polar latitudes from a period of warm climatic conditions during the Pliocene (15-20 °C warmer mean annual temperature than the present day). In this regard it is possible to speculate that the transport of large amounts of woody debris as bedload is potentially a unique feature of forested high latitude rivers. Such bedload deposition requires a large amount of woody debris with a greater density than the fluid transporting it. The softwood composition of the debris suggests that this was most likely attained by saturation and subsequent entrainment of extensive accumulations of deadwood, promoted by unusually high rates of tree mortality and low rates of bacterial decomposition arising from

  10. Designing for informed group formation

    DEFF Research Database (Denmark)

    Nicolajsen, Hanne Westh; Juel Jacobsen, Alice; Riis, Marianne

    2012-01-01

    A new design ―project preparation‖ preparing for the group formation in problem based project work is proposed and investigated. The main problem is to overcome group formation based on existing relations. The hypothesis is that theme development and group formation are somewhat counterproductive....... Following research based design methodology an experiment separating the two was initiated.This was to provide for more openness and creativity in contrast to a design in which existing relations seem predominant....

  11. 76 FR 78820 - Safety Zone; City of Beaufort's Tricentennial New Year's Eve Fireworks Display, Beaufort River...

    Science.gov (United States)

    2011-12-20

    ...-AA00 Safety Zone; City of Beaufort's Tricentennial New Year's Eve Fireworks Display, Beaufort River... establishing a temporary safety zone on the Beaufort River, in Beaufort, South Carolina, during the City of... Carolina. The fireworks will be launched from a barge, which will be located on the Beaufort River. The...

  12. Paleomagnetism and Magnetostratigraphy of Upper Permian to Lower Triassic (?) Beaufort Group Strata at Bethulie, Karoo Basin, Free State Province, South Africa

    Science.gov (United States)

    Geissman, J. W.; Gastaldo, R. A.; Neveling, J.; Makubalo, S.

    2017-12-01

    A multifaceted approach to understand the timing of interpreted environmental changes during the Late Permian to possibly Early Triassic (?) time in the Beaufort Group strata of the Karoo Basin includes work to establish robust magnetic polarity records for sections previously interpreted to encompass end-Permian extinction events. Demonstrating the preservation of an early-acquired remanence (RM) in Karoo strata is required for a robust magnetostratigraphy. Yet, this is challenging due to thermochemical effects related to the Early Jurassic (ca. 183 Ma) Karoo Large Igneous Province (LIP), and the NE to SW increase in burial diagenesis attending Cape Fold Belt tectonism. Documentation of a primary RM in these strata, which appears to be preserved in some areas, requires careful laboratory- and field-based assessment. We report data from 53 sites collected at the well-studied Bethulie section, Free State Province, in which several samples per individual horizon to assess ChRM uniformity. Strata well-removed from dikes yield both normal and reverse polarity ChRM. It is always the case that the first-removed RM is a NNW seeking, moderate to steep negative-inclination ChRM (normal polarity); NRM intensities are typically 1 to 5 mA/m. Sites BT15 and BT21, which are located in strata lying some 4 m below the often-cited "event bed" interval inferred to be the terrestrial expression of the Permian/Triassic boundary, is dominated by a well-defined reverse RM with a normal overprint RM unblocked below 400oC, implying elevated temperatures (i.e., 100 to 250oC+) for ca. 1 Ma (+/-). Contact tests are positive but complicated. Host strata collected in distances equal to or less than 1-2 dike widths from the intrusions have been thermally remagnetized and demonstrate high NRM intensities (> 50 mA/m). Collectively, we interpret these data to indicate that any ChRM, with the exception of those from host strata in baked contacts, that persists above Tlub of 425oC is pre-Karoo LIP

  13. Group formation in early clinical project

    DEFF Research Database (Denmark)

    Østergaard, Gert Værge

    Research shows that getting involved is a key aspect of learning, and a way of getting involved is through study groups [1]. Forming groups are always a theme that is discussed, both amongst faculty and students. There is a different approach at different semesters regarding this formation...

  14. Consensus formation on coevolving networks: groups' formation and structure

    International Nuclear Information System (INIS)

    Kozma, Balazs; Barrat, Alain

    2008-01-01

    We study the effect of adaptivity on a social model of opinion dynamics and consensus formation. We analyse how the adaptivity of the network of contacts between agents to the underlying social dynamics affects the size and topological properties of groups and the convergence time to the stable final state. We find that, while on static networks these properties are determined by percolation phenomena, on adaptive networks the rewiring process leads to different behaviors: adaptive rewiring fosters group formation by enhancing communication between agents of similar opinion, though it also makes possible the division of clusters. We show how the convergence time is determined by the characteristic time of link rearrangement. We finally investigate how the adaptivity yields nontrivial correlations between the internal topology and the size of the groups of agreeing agents

  15. Formation and ridging of flaw leads in the eastern Canadian Beaufort Sea. Special Session C06 on: “Physical, biological and biogeochemical processes associated with young thin ice types”

    Science.gov (United States)

    Prinsenberg, S. J.

    2009-12-01

    Formation and ridging of flaw leads in the eastern Canadian Beaufort Sea. Simon Prinsenberg1 and Yves Graton2 1Bedford Inst. of Oceanography, Fisheries and Oceans Canada P.O. Box1006, Dartmouth, Nova Scotia, B2Y 4A2, Canada prinsenbergs@mar.dfo-mpo.gc.ca 2Inst. National de la Recherche Scientifique-Eau, INRS-ETE University of Quebec at Quebec City, Quebec yvesgratton@eteinrs.ca During the winter of 2008, the flaw lead south of Banks Island repeatedly opened and closed representing an elongated region where periodically the large ice growth stimulates the densification of the surface layer due to salt rejection and instigates a local circulation pattern that will affect the biological processes of the region. Helicopter-borne sensors were available to monitor the aftermath of one of the rapid closing of the flaw lead into extensive elongated rubble field using a Canadian Ice breaker, CCGS Amundsen, as a logistic base. After the wind reversed a new open flaw lead 20km wide restarting a new flaw lead formation cycle. Ice thickness and surface roughness data were collected from the rubble field and adjacent open flaw lead with an Electromagnetic-Laser system. The strong wind event of April 4-5 2009 generated a large linear 1.5km wide ice rubble field up to 8-10m thick when the 60cm thick, 18km wide flaw lead was crunched into land-fast by the 1.5m thick offshore pack ice. It is expected that during rapid ice growth in a flaw lead, salt rejection increase the density of the surface water layer producing a surface depression (Low) and cyclonic circulation. In contrast at depth, the extra surface dense water produces a high in the horizontal pressure field and anti-cyclonic circulation which remains after the rapid ice growth within the flaw lead stops. One of such remnants may have been observed during the CFL-IPY winter survey.

  16. Expert group formation using facility location analysis

    NARCIS (Netherlands)

    Neshati, M.; Beigy, H.; Hiemstra, Djoerd

    In this paper, we propose an optimization framework to retrieve an optimal group of experts to perform a multi-aspect task. While a diverse set of skills are needed to perform a multi-aspect task, the group of assigned experts should be able to collectively cover all these required skills. We

  17. Expert group formation using facility location analysis

    NARCIS (Netherlands)

    Neshati, Mahmood; Beigy, Hamid; Hiemstra, Djoerd

    2014-01-01

    In this paper, we propose an optimization framework to retrieve an optimal group of experts to perform a multi-aspect task. While a diverse set of skills are needed to perform a multi-aspect task, the group of assigned experts should be able to collectively cover all these required skills. We

  18. 2013 South Carolina DNR Lidar: Beaufort County

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — LMSI provided high accuracy, calibrated multiple return LiDAR for roughly 785 square miles covering Beaufort County, South Carolina. The nominal point spacing for...

  19. Aspects of uranium mineralization in the Beaufort West Karoo

    Energy Technology Data Exchange (ETDEWEB)

    Pretorius, L E

    1977-01-01

    The distribution and controlling factors of uranium mineralization in the sedimentary rocks of the Lower Beaufort Group have been investigated in the Beaufort West area between 22/sup 0/O' and 24/sup 0/O'E longitude and 32/sup 0/O' and 32/sup 0/45'S latitude. The mineralization is classified as 'primary' or 'secondary', depending on the time of emplacement and not on the oxidation state of the uranium minerals present. Petrographic and geochemical aspects of primary uranium deposition point to a syngenetic origin. Reconstruction of the paleodepositional environment suggests that the primary mineralization is restricted to paleo-pools or -meander cut-offs where stagnant reducing conditions existed. From geological mapping done to the south of Beaufort West it appears that this uranium mineralization is located in an 'intermediate' paleo-depositional zone between the true fluvial and delta front environments. The indications of secondary uranium distribution and epigenetic concentration in 'rolls' within the area were studied along with various other aspects of such mineralization. The permeability of the arenaceous rocks in the area seems to be too low to host large uranium deposits of this kind. Detail geochemical soil sampling suggests that Zn, P, Co and As could be used as pathfinder elements for uranium. Although regional anomalies were investigated no meaningful pattern could be developed.

  20. Star formation suppression in compact group galaxies

    DEFF Research Database (Denmark)

    Alatalo, K.; Appleton, P. N.; Lisenfeld, U.

    2015-01-01

    , bars, rings, tidal tails, and possibly nuclear outflows, though the molecular gas morphologies are more consistent with spirals and earlytype galaxies than mergers and interacting systems. Our CO-imaged HCG galaxies, when plotted on the Kennicutt-Schmidt relation, shows star formation (SF) suppression...... color space. This supports the idea that at least some galaxies in HCGs are transitioning objects, where a disruption of the existing molecular gas in the system suppresses SF by inhibiting the molecular gas from collapsing and forming stars efficiently. These observations, combined with recent work...

  1. Risk behaviour and group formation in microcredit groups in Eritrea

    NARCIS (Netherlands)

    Lensink, Robert; Mehrteab, Habteab T.

    2003-01-01

    We conducted a survey in 2001 among members and group leaders of borrowers who accessed loans from two microcredit programs in Eritrea. Using the results from this survey, this paper aims to provide new insights into the empirical relevance of the homogeneous matching hypothesis for microcredit

  2. Risk Behaviour and Group Formation in Microcredit Groups in Eritrea

    NARCIS (Netherlands)

    Lensink, B.W.; Mehrteab, H.T.

    2006-01-01

    We conducted a survey in 2001 among members and group leaders of borrowers who accessed loans from two microcredit programs in Eritrea. Using the results from this survey, this paper aims to provide new insights into the empirical relevance of the homogeneous matching hypothesis for microcredit

  3. Politics and Business Group Formation in China

    DEFF Research Database (Denmark)

    Brødsgaard, Kjeld Erik

    2012-01-01

    As a result of economic reform and administrative restructuring in China, a number of powerful state-owned business groups (“national champions”) have emerged within sectors of strategic importance. They are headed by a new corporate elite which enjoys unprecedentedly high levels of remuneration...... makes it possible to transfer/rotate business leaders to take up positions in state and Party agencies. In order to conceptualize the coexistence of the contradicting forces for further enterprise autonomy and continued central control that characterizes the evolving relationship between business groups...

  4. Beaufort Sea planning area oil and gas Lease Sale 170. Final environmental impact statement

    International Nuclear Information System (INIS)

    1998-02-01

    This environmental impact statement (EIS) assesses Lease Sale 170 proposed for August 1998 and comprised of 363 lease blocks in the Beaufort Sea planning area. The analysis addresses the significant environmental and socioeconomic concerns identified in the scoping process. Scoping consisted of input from State and Federal agencies, the petroleum industry, Native groups, environmental and public interest groups, and concerned individuals. The potential effects expected from the interaction between environmental resources and OCS-related activities were determined with respect to available scientific information and traditional knowledge. This EIS incorporates information from the Final EIS for the Beaufort Sea OCS Sale 144 (USD01, MMS, 1996a)

  5. The formation of group norms in computer-mediated communication

    NARCIS (Netherlands)

    Postmes, T; Spears, R; Lea, M

    The formation of group norms in computer-mediated communication (CMC) was examined among students who used e-mail as part of a course. A network analysis of group structures revealed that (a) content and form of communication is normative, group norms defining communication patterns within groups,

  6. Atmospheric forcing of sea ice leads in the Beaufort Sea

    Science.gov (United States)

    Lewis, B. J.; Hutchings, J.; Mahoney, A. R.; Shapiro, L. H.

    2016-12-01

    Leads in sea ice play an important role in the polar marine environment where they allow heat and moisture transfer between the oceans and atmosphere and act as travel pathways for both marine mammals and ships. Examining AVHRR thermal imagery of the Beaufort Sea, collected between 1994 and 2010, sea ice leads appear in repeating patterns and locations (Eicken et al 2005). The leads, resolved by AVHRR, are at least 250m wide (Mahoney et al 2012), thus the patterns described are for lead systems that extend up to hundreds of kilometers across the Beaufort Sea. We describe how these patterns are associated with the location of weather systems relative to the coastline. Mean sea level pressure and 10m wind fields from ECMWF ERA-Interim reanalysis are used to identify if particular lead patterns can be uniquely forecast based on the location of weather systems. Ice drift data from the NSIDC's Polar Pathfinder Daily 25km EASE-Grid Sea Ice Motion Vectors indicates the role shear along leads has on the motion of ice in the Beaufort Gyre. Lead formation is driven by 4 main factors: (i) coastal features such as promontories and islands influence the origin of leads by concentrating stresses within the ice pack; (ii) direction of the wind forcing on the ice pack determines the type of fracture, (iii) the location of the anticyclone (or cyclone) center determines the length of the fracture for certain patterns; and (iv) duration of weather conditions affects the width of the ice fracture zones. Movement of the ice pack on the leeward side of leads originating at promontories and islands increases, creating shear zones that control ice transport along the Alaska coast in winter. . Understanding how atmospheric conditions influence the large-scale motion of the ice pack is needed to design models that predict variability of the gyre and export of multi-year ice to lower latitudes.

  7. Arctic Storms and Their Influence on Surface Climate in the Chukchi-Beaufort Seas

    Science.gov (United States)

    Yang, Y.; Zhang, X.; Rinke, A.; Zhang, J.

    2017-12-01

    Increases in the frequency and intensity of Arctic storms and resulting weather hazards may endanger the offshore environment, coastal community, and energy infrastructure in the Arctic as sea ice retreats. Advancing ability to identify fine-scale variations in surface climate produced by progressively stronger storm would be extremely helpful to resources management and sustainable development for coastal community. In this study, we analyzed the storms and their impacts on surface climate over the Beaufort-Chukchi seas by employing the date sets from both the hindcast simulations of the coupled Arctic regional climate model HIRHAM-NAOSIM and the recently developed Chukchi-Beaufort High-resolution Atmospheric Reanalysis (CBHAR). Based on the characteristics of spatial pattern and temporal variability of the Arctic storm activity, we categorized storms to three groups with their different origins: the East Siberia Sea, Alaska and the central Arctic Ocean. The storms originating from the central Arctic Ocean have the strongest intensity in winter with relatively less storm number. Storms traveling from Alaska to the Beaufort Sea most frequently occurred in autumn with weaker intensity. A large portion of storms originated from the East Siberia Sea region in summer. Further statistical analysis suggests that increase in surface air temperature and wind speed could be attributed to the increased frequency of storm occurrence in autumn (September to November) along the continental shelf in the Beaufort Sea.

  8. Network formation under heterogeneous costs: The multiple group model

    NARCIS (Netherlands)

    Kamphorst, J.J.A.; van der Laan, G.

    2007-01-01

    It is widely recognized that the shape of networks influences both individual and aggregate behavior. This raises the question which types of networks are likely to arise. In this paper we investigate a model of network formation, where players are divided into groups and the costs of a link between

  9. Stepfamily Education: Benefits of a Group-Formatted Intervention

    Science.gov (United States)

    Skogrand, Linda; Torres, Eliza; Higginbotham, Brian J.

    2010-01-01

    This program evaluation was conducted by interviewing 40 low-income participants in a relationship education (RE) program for stepfamilies to determine specific benefits of a group-formatted intervention. The benefits that were most often identified were learning from others and having personal stepfamily challenges normalized. Participants also…

  10. A New Group-Formation Method for Student Projects

    Science.gov (United States)

    Borges, Jose; Dias, Teresa Galvao; Cunha, Joao Falcao E.

    2009-01-01

    In BSc/MSc engineering programmes at Faculty of Engineering of the University of Porto (FEUP), the need to provide students with teamwork experiences close to a real world environment was identified as an important issue. A new group-formation method that aims to provide an enriching teamwork experience is proposed. Students are asked to answer a…

  11. Acritarchs of the Ediacaran Frecheirinha Formation, Ubajara Group, Northeastern Brazil

    Directory of Open Access Journals (Sweden)

    Leticia Chiglino

    2015-06-01

    Full Text Available We report for the first time the occurrence of organic-walled microfossils in Ediacaran limestones and marls of the Frecheirinha Formation, Ubajara Group, and the first Precambrian acritarchs so far reported for northeastern Brazil. The assemblage of the Frecheirinha Formation represents a low-diversity microflora comprising Leiosphaeridia, Lophosphaeridium and subordinated Bavlinella (=Sphaerocongregus. Their thermal alteration index (TAI between 4+ and 5, suggests metamorphic temperatures exceeding 200-250°C. Higher temperatures are probably related to intruding granitic plutons (Meruoca, Mucambo. Reported δ13C values of carbonates of -3.5 ‰ VPDB (Vienna-Peedee Belemnite at the base, passing up section into a positive plateau of up to +3.7 ‰, and corresponding 87Sr/86Sr values between 0.7075 and 0.7080 suggest an Ediacaran age. The acritarch assemblage is comparable to the Late Ediacaran Leiosphere Palynoflora (LELP or Kotlin-Rovno assemblage, in broad agreement with chemostratigraphic data. Macrofossils belonging to the Ediacara fauna were reported from the overlying Jaibaras Group, which would constrain even further the depositional age of the Frecheirinha Formation to within ca. 575-555 Ma. A more comprehensive palynological study of the Frecheirinha Formation is necessary to confirm this age assignment.

  12. solving the cell formation problem in group technology

    Directory of Open Access Journals (Sweden)

    Prafulla Joglekar

    2001-01-01

    Full Text Available Over the last three decades, numerous algorithms have been proposed to solve the work-cell formation problem. For practicing manufacturing managers it would be nice to know as to which algorithm would be most effective and efficient for their specific situation. While several studies have attempted to fulfill this need, most have not resulted in any definitive recommendations and a better methodology of evaluation of cell formation algorithms is urgently needed. Prima facie, the methodology underlying Miltenburg and Zhang's (M&Z (1991 evaluation of nine well-known cell formation algorithms seems very promising. The primary performance measure proposed by M&Z effectively captures the objectives of a good solution to a cell formation problem and is worthy of use in future studies. Unfortunately, a critical review of M&Z's methodology also reveals certain important flaws in M&Z's methodology. For example, M&Z may not have duplicated each algorithm precisely as the developer(s of that algorithm intended. Second, M&Z's misrepresent Chandrasekharan and Rajagopalan's [C&R's] (1986 grouping efficiency measure. Third, M&Z's secondary performance measures lead them to unnecessarily ambivalent results. Fourth, several of M&Z's empirical conclusions can be theoretically deduced. It is hoped that future evaluations of cell formation algorithms will benefit from both the strengths and weaknesses of M&Z's work.

  13. THE FORMATION OF CONSCIENCE AND MANAGEMENT GROUPS IN ORGANIZATIONS

    Directory of Open Access Journals (Sweden)

    Neisa Maria, Martins da Cunha

    2010-01-01

    Full Text Available This paper presents theoretical proposals, as the Theory of Human Relations, especially the Theory of Group Dynamics and the Conscience Formation, which promote understanding and support for the conduct of the leaders in team management, aiming at a route suitable for questions, reflections, enabling new perceptions of self-consciousness, as Hegel says. It is worth highlighting that through these considerations, it becomes possible to conduct more realistic impacts triggered in the organizational culture, as from a better management of interpersonal relationships within teams, these teams have a training goal or not.

  14. Collapse of the 2017 Winter Beaufort High: A Response to Thinning Sea Ice?

    Science.gov (United States)

    Moore, G. W. K.; Schweiger, A.; Zhang, J.; Steele, M.

    2018-03-01

    The winter Arctic atmosphere is under the influence of two very different circulation systems: extratropical cyclones travel along the primary North Atlantic storm track from Iceland toward the eastern Arctic, while the western Arctic is characterized by a quasi-stationary region of high pressure known as the Beaufort High. The winter (January through March) of 2017 featured an anomalous reversal of the normally anticyclonic surface winds and sea ice motion in the western Arctic. This reversal can be traced to a collapse of the Beaufort High as the result of the intrusion of low-pressure systems from the North Atlantic, along the East Siberian Coast, into the Arctic Basin. Thin sea ice as the result of an extremely warm autumn (October through December) of 2016 contributed to the formation of an anomalous thermal low over the Barents Sea that, along with a northward shift of the tropospheric polar vortex, permitted this intrusion. The collapse of the Beaufort High during the winter of 2017 was associated with simultaneous 2-sigma sea level pressure, surface wind, and sea ice circulation anomalies in the western Arctic. As the Arctic sea ice continues to thin, such reversals may become more common and impact ocean circulation, sea ice, and biology.

  15. Eocene Yegua Formation (Claiborne group) and Jackson group lignite deposits of Texas

    Science.gov (United States)

    Hook, Robert W.; Warwick, Peter D.; Swanson, Sharon M.; Hackley, Paul C.; Warwick, Peter D.; Karlsen, Alexander K.; Merrill, Matthew D.; Valentine, Brett J.

    2011-01-01

    The lignite deposits within the upper Eocene Yegua Formation (Claiborne Group) and the overlying Jackson Group are among the coal resources that were not quantitatively assessed as part of the U.S. Geological Survey's (USGS) National Coal Resource Assessment (NCRA) program in the Gulf Coastal Plain coal province. In the past, these lignite-bearing stratigraphic units often have been evaluated together because of their geographic and stratigraphic proximity (Fisher, 1963; Kaiser, 1974; Kaiser et al., 1980; Jackson and Garner, 1982; Kaiser, 1996) (Figures 1, 2). The term “Yegua-Jackson trend“ is used informally herein for the lignite-bearing outcrops of these Late Eocene deposits in Texas. Lignite beds in the Yegua-Jackson trend generally are higher both in ash yield and sulfur content than those of the underlying Wilcox Group (Figure 2). Recent studies (Senkayi et al., 1987; Ruppert et al., 1994; Warwick et al., 1996, 1997) have shown that some lignite beds within the Yegua-Jackson trend contain partings of volcanic ash and host elevated levels of trace elements that have been identified as potentially hazardous air pollutants (HAPs) in the United States Clean Air Amendments of 1990. Lignite beds within the Yegua Formation are thin (less than or equal to 6 ft) and laterally discontinuous in comparison with most Wilcox Group deposits (Ayers, 1989a); in contrast, the Jackson Group lignite beds range up to 12 ft in total thickness and are relatively continuous laterally, extending nearly 32 mi along strike.

  16. Pigment signatures of phytoplankton communities in the Beaufort Sea

    Science.gov (United States)

    Coupel, P.; Matsuoka, A.; Ruiz-Pino, D.; Gosselin, M.; Marie, D.; Tremblay, J.-É.; Babin, M.

    2015-02-01

    Phytoplankton are expected to respond to recent environmental changes of the Arctic Ocean. In terms of bottom-up control, modifying the phytoplankton distribution will ultimately affect the entire food web and carbon export. However, detecting and quantifying changes in phytoplankton communities in the Arctic Ocean remains difficult because of the lack of data and the inconsistent identification methods used. Based on pigment and microscopy data sampled in the Beaufort Sea during summer 2009, we optimized the chemotaxonomic tool CHEMTAX (CHEMical TAXonomy) for the assessment of phytoplankton community composition in an Arctic setting. The geographical distribution of the main phytoplankton groups was determined with clustering methods. Four phytoplankton assemblages were determined and related to bathymetry, nutrients and light availability. Surface waters across the whole survey region were dominated by prasinophytes and chlorophytes, whereas the subsurface chlorophyll maximum was dominated by the centric diatoms Chaetoceros socialis on the shelf and by two populations of nanoflagellates in the deep basin. Microscopic counts showed a high contribution of the heterotrophic dinoflagellates Gymnodinium and Gyrodinium spp. to total carbon biomass, suggesting high grazing activity at this time of the year. However, CHEMTAX was unable to detect these dinoflagellates because they lack peridinin. In heterotrophic dinoflagellates, the inclusion of the pigments of their prey potentially leads to incorrect group assignments and some misinterpretation of CHEMTAX. Thanks to the high reproducibility of pigment analysis, our results can serve as a baseline to assess change and spatial or temporal variability in several phytoplankton populations that are not affected by these misinterpretations.

  17. Group Supervision in Psychotherapy. Main Findings from a Swedish Research Project on Psychotherapy Supervision in a Group Format

    Science.gov (United States)

    Ogren, Marie-Louise; Sundin, Eva C.

    2009-01-01

    Psychotherapy supervision is considered crucial for psychotherapists in training. During the last decades, group supervision has been a frequently used format in many countries. Until recently, very few studies had evaluated the small-group format for training of beginner psychotherapists and psychotherapy supervisors. This article aims to…

  18. 75 FR 61094 - Drawbridge Operation Regulation; Atlantic Intracoastal Waterway, Beaufort, SC

    Science.gov (United States)

    2010-10-04

    .... Highway 21, Sea Island Parkway Bridge at mile marker 536 over the Beaufort River (Atlantic Intracoastal... Bridge, which is across the Atlantic Intracoastal Waterway at mile 539.0 in Port Royal, South Carolina... Bridge, across the Beaufort River, Mile 536.0 at Beaufort. The draw shall operate as follows: (1) On...

  19. A Framework for Semantic Group Formation in Education

    Science.gov (United States)

    Ounnas, Asma; Davis, Hugh C.; Millard, David E.

    2009-01-01

    Collaboration has long been considered an effective approach to learning. However, forming optimal groups can be a time consuming and complex task. Different approaches have been developed to assist teachers allocate students to groups based on a set of constraints. However, existing tools often fail to assign some students to groups creating a…

  20. Cognitive Behavior Therapy: A Comparison of Group and Individual Formats.

    Science.gov (United States)

    Shaffer, Carolyn S.; And Others

    The relative efficacy of both group and individual cognitive behavior therapeutic approaches in treating anxiety and depression are evaluated and then compared to an interpersonal group therapy approach. The two major hypotheses are that group cognitive behavior therapy is at least as effective as individual cognitive behavior therapy, and that…

  1. The formation of heterodimers by vancomycin group antibiotics

    DEFF Research Database (Denmark)

    Staroske, T; O'Brien, DP; Jørgensen, Thomas J. D.

    2000-01-01

    The formation of heterodimers in mixtures of glycopeptide antibiotics has been detected by electrospray ionization mass spectrometry (ESI-MS), and dimerization constants have been determined. By using NMR spectroscopy, it has been shown that these heterodimers indeed exist in aqueous solution...

  2. Dwarf Spheroidal Satellite Formation in a Reionized Local Group

    OpenAIRE

    Milosavljevic, Milos; Bromm, Volker

    2013-01-01

    Dwarf spheroidal satellite galaxies have emerged a powerful probe of small-scale dark matter clustering and of cosmic reionization. They exhibit structural and chemical continuity with dwarf irregular galaxies in the field and with spheroidal galaxies in high-density environments. By combining empirical constraints derived for star formation at low gas column densities and metallicities in the local universe with a model for dark matter and baryonic mass assembly, we provide an analytical des...

  3. Multi-Aspect Group Formation using Facility Location Analysis

    NARCIS (Netherlands)

    Neshati, Mahmood; Beigy, Hamid; Hiemstra, Djoerd

    2012-01-01

    In this paper, we propose an optimization framework to retrieve an optimal group of experts to perform a given multi-aspect task/project. Each task needs a diverse set of skills and the group of assigned experts should be able to collectively cover all required aspects of the task. We consider three

  4. Beaufort Region Environmental Assessment and Monitoring program (BREAM). Final report for 1992/1993

    International Nuclear Information System (INIS)

    Vonk, P.; Duval, W.; Thomas, D.

    1993-01-01

    The Beaufort Region Environmental Assessment and Monitoring (BREAM) program was established to identify environmental research and monitoring priorities related to future hydrocarbon development activities in the Beaufort Sea and Mackenzie Delta region. The activities occurring during the third year of BREAM focused on major oil spills. Three planning meetings were held: a Project Initiation Meeting and technical meetings of the Community-Based Concerns and Catastrophic Oil Spill Working Groups. The initiation meeting had goals that included identifying specific tasks to be completed by the two Working Groups, discussion of contents and scope of materials being prepared for an oil spill workshop, and determining project schedules. The Community-Based Concerns group focused its work on identifying ecological concerns related to oil spills and their cleanup, identifying community-based ecological issues and concerns, and incorporating local and traditional knowledge into the BREAM program. The group suggested changes to the wording of existing impact hypotheses and oil spill scenarios, and recommended changes in a list of valued ecosystem components. The oil spill group reviewed ecological concerns related to oil spills, and reviewed each oil spill scenario and impact hypothesis selected for an interdisciplinary workshop held in February 1993. The workshop evaluated four of the most important oil spill impact hypotheses (offshore platform blowout, river barge spill of diesel fuel, under-ice spill from a pipeline river crossing, and a pipeline spill affecting mammals). Further research and monitoring related to a number of impact hypotheses was recommended by workshop participants. 57 refs., 29 figs., 12 tabs

  5. Spontaneous formation of dynamical groups in an adaptive networked system

    International Nuclear Information System (INIS)

    Li Menghui; Guan Shuguang; Lai, C-H

    2010-01-01

    In this work, we investigate a model of an adaptive networked dynamical system, where the coupling strengths among phase oscillators coevolve with the phase states. It is shown that in this model the oscillators can spontaneously differentiate into two dynamical groups after a long time evolution. Within each group, the oscillators have similar phases, while oscillators in different groups have approximately opposite phases. The network gradually converts from the initial random structure with a uniform distribution of connection strengths into a modular structure that is characterized by strong intra-connections and weak inter-connections. Furthermore, the connection strengths follow a power-law distribution, which is a natural consequence of the coevolution of the network and the dynamics. Interestingly, it is found that if the inter-connections are weaker than a certain threshold, the two dynamical groups will almost decouple and evolve independently. These results are helpful in further understanding the empirical observations in many social and biological networks.

  6. An Ontology Engineering Approach to the Realization of Theory-Driven Group Formation

    Science.gov (United States)

    Isotani, Seiji; Inaba, Akiko; Ikeda, Mitsuru; Mizoguchi, Riichiro

    2009-01-01

    One of the main difficulties during the design of collaborative learning activities is adequate group formation. In any type of collaboration, group formation plays a critical role in the learners' acceptance of group activities, as well as the success of the collaborative learning process. Nevertheless, to propose both an effective and…

  7. Cooperation during cultural group formation promotes trust towards members of out-groups.

    Science.gov (United States)

    Pan, Xiaofei Sophia; Houser, Daniel

    2013-07-07

    People often cooperate with members of their own group, and discriminate against members of other groups. Previous research establishes that cultural groups can form endogenously, and that these groups demonstrate in-group favouritism. Given the presence of cultural groups, the previous literature argues that cultural evolution selects for groups that exhibit parochial altruism. The source of initial variation in these traits, however, remains uninformed. We show here that a group's economic production environment may substantially influence parochial tendencies, with groups formed around more cooperative production (CP) displaying less parochialism than groups formed around more independent production (IP) processes. Participants randomized into CP and IP production tasks formed cultural groups, and subsequently played hidden-action trust games with in-group and out-group trustees. We found CP to be associated with significantly greater sharing and exchanging behaviours than IP. In trust games, significant parochial altruism (in-group favouritism combined with out-group discrimination) was displayed by members of IP groups. By contrast, members of CP groups did not engage in either in-group favouritism or out-group discrimination. Further, we found the absence of out-group discrimination in CP to persist even following 'betrayal'. Finally, belief data suggest that members of CP are not more intrinsically generous than IP members, but rather more likely to believe that out-group trustees will positively reciprocate. Our results have important implications for anyone interested in building cooperative teams, and shed new light on connections between culture and cooperation.

  8. Cultural Differences in Alliance Formation during Group Supervision.

    Science.gov (United States)

    Carter, John W.; Pak, Jenny H.; Goodyear, Rodney K.

    Study tested whether general differences between Asian and European-American cultures (interdependent vs. independent orientation, levels of self-disclosure and conflict in social relationships) would have an effect on the supervisory process of counseling trainees. On the context of weekly group supervision, first-year counseling trainees were…

  9. Determining volume sensitive waters in Beaufort County, SC tidal creeks

    Science.gov (United States)

    Andrew Tweel; Denise Sanger; Anne Blair; John Leffler

    2016-01-01

    Non-point source pollution from stormwater runoff associated with large-scale land use changes threatens the integrity of ecologically and economically valuable estuarine ecosystems. Beaufort County, SC implemented volume-based stormwater regulations on the rationale that if volume discharge is controlled, contaminant loading will also be controlled.

  10. 33 CFR 117.822 - Beaufort Channel, NC.

    Science.gov (United States)

    2010-07-01

    ... DRAWBRIDGE OPERATION REGULATIONS Specific Requirements North Carolina § 117.822 Beaufort Channel, NC. The... bridge need not open between the hours of 6:30 a.m. to 8 a.m. and 4:30 p.m. to 6 p.m. (b) From 10 p.m. to...

  11. Fixed geometric formation structure in formation control problem for group of robots with dynamically changing number of robots in the group

    Directory of Open Access Journals (Sweden)

    N. S. Morozova

    2015-01-01

    Full Text Available The article considers a problem of the decentralization-based approach to formation control of a group of agents, which simulate mobile autonomous robots. The agents use only local information limited by the covering range of their sensors. The agents have to build and maintain the formation, which fits to the defined target geometric formation structure with desired accuracy during the movement to the target point. At any point in time the number of agents in the group can change unexpectedly (for example, as a result of the agent failure or if a new agent joins the group.The aim of the article is to provide the base control rule, which solves the formation control problem, and to develop its modifications, which provide the correct behavior in case the agent number in the group is not equal to the size of the target geometric formation structure. The proposed base control rule, developed by the author, uses the method of involving virtual leaders. The coordinates of the virtual leaders and also the priority to follow the specific leader are calculated by each agent itself according to specific rules.The following results are presented in the article: the base control rule for solving the formation control problem, its modifications for the cases when the number of agents is greater/less than the size of the target geometric formation structure and also the computer modeling results proving the efficiency of the modified control rules. The specific feature of the control rule, developed by the author, is that each agent itself calculates the virtual leaders and each agent performs dynamic choice of the place within the formation (there is no predefined one-to-one relation between agents and places within the geometric formation structure. The results, provided in this article, can be used in robotics for developing control algorithms for the tasks, which require preserving specific relational positions among the agents while moving. One of the

  12. Meteorological Support Interface Control Working Group (MSICWG) Instrumentation, Data Format, and Networks Document

    Science.gov (United States)

    Brenton, James; Roberts, Barry C.

    2017-01-01

    The purpose of this document is to provide an overview of instrumentation discussed at the Meteorological Interface Control Working Group (MSICWG), a reference for data formats currently used by members of the group, a summary of proposed formats for future use by the group, an overview of the data networks of the group's members. This document will be updated as new systems are introduced, old systems are retired, and when the MSICWG community necessitates a change to the formats. The MSICWG consists of personnel from the National Aeronautics and Space Administration (NASA) Kennedy Space Center (KSC), NASA Marshall Space Flight Center (MSFC), NASA Johnson Space Center (JSC), National Oceanic and Atmospheric Administration National Weather Service Spaceflight Meteorology Group (SMG), and the United States Air Force (USAF) 45th Space Wing and Weather Squadron. The purpose of the group is to coordinate the distribution of weather related data to support NASA space launch related activities.

  13. Investigating Arctic Sea Ice Survivability in the Beaufort Sea

    Directory of Open Access Journals (Sweden)

    Matthew Tooth

    2018-02-01

    Full Text Available Arctic sea ice extent has continued to decline in recent years, and the fractional coverage of multi-year sea ice has decreased significantly during this period. The Beaufort Sea region has been the site of much of the loss of multi-year sea ice, and it continues to play a large role in the extinction of ice during the melt season. We present an analysis of the influence of satellite-derived ice surface temperature, ice thickness, albedo, and downwelling longwave/shortwave radiation as well as latitude and airborne snow depth estimates on the change in sea ice concentration in the Beaufort Sea from 2009 to 2016 using a Lagrangian tracking database. Results from this analysis indicate that parcels that melt during summer in the Beaufort Sea reside at lower latitudes and have lower ice thickness at the beginning of the melt season in most cases. The influence of sea ice thickness and snow depth observed by IceBridge offers less conclusive results, with some years exhibiting higher thicknesses/depths for melted parcels. Parcels that melted along IceBridge tracks do exhibit lower latitudes and ice thicknesses, however, which indicates that earlier melt and breakup of ice may contribute to a greater likelihood of extinction of parcels in the summer.

  14. A nitrous acid biosynthetic pathway for diazo group formation in bacteria.

    Science.gov (United States)

    Sugai, Yoshinori; Katsuyama, Yohei; Ohnishi, Yasuo

    2016-02-01

    Although some diazo compounds have bioactivities of medicinal interest, little is known about diazo group formation in nature. Here we describe an unprecedented nitrous acid biosynthetic pathway responsible for the formation of a diazo group in the biosynthesis of the ortho-diazoquinone secondary metabolite cremeomycin in Streptomyces cremeus. This finding provides important insights into the biosynthetic pathways not only for diazo compounds but also for other naturally occurring compounds containing nitrogen-nitrogen bonds.

  15. Risk-matching behavior in microcredit group formation: evidence from northern Ethiopia

    NARCIS (Netherlands)

    Berhane Tesfay, G.; Gardebroek, C.; Moll, H.A.J.

    2009-01-01

    Theoretical models on group lending assume the formation of groups of homogenous risk types. Recent theoretical and empirical findings challenge this view arguing that when markets for insurance are missing, risk homogeneity may not hold any more and risk heterogeneity can be the optimal outcome.

  16. Implementation of a Personnel Management System "Beaufort": Successes and failures at a Dutch Hospital

    NARCIS (Netherlands)

    Bondarouk, Tatiana; Khosrow-Pour, M.

    2004-01-01

    This case describes a project concerning the implementation of a personnel management system - Beaufort - in Medinet, one of the larger regional general hospitals in The Netherlands. The project plan included two sequential phases: firstly, the introduction of Beaufort to the central personnel and

  17. Experimental and Kinetic Investigation of the Influence of OH Groups on NOX Formation

    KAUST Repository

    Bohon, Myles

    2016-05-04

    This work investigates the influence of one or more OH groups present on the fuel molecule and the resultant formation of NOX emissions. Combustion of oxygenated fuels has been increasing globally and such fuels offer significant potential in the reduction of pollutant emissions. One such emission class is the oxides of nitrogen, which typically form through a combination of two regimes: the thermal and non-thermal mechanisms. While thermal NO formation can be reduced by lowering the combustion temperature, non-thermal NO formation is coupled to the fuel chemistry. An experimental and computational investigation of NOX formation in three different burner configurations and under a range of equivalence ratios and temperature regimes explored the differences in NO formation. Measurements of temperature profiles and in-flame species concentrations, utilizing both probed and non-intrusive laser based techniques, allowed for the investigation of NO formation through non-thermal pathways and the differences that exist between fuels with varying numbers of OH groups. The first burner configuration was composed of a high swirl liquid spray burner with insulted combustion chamber walls designed specifically for the combustion of low energy density fuels. In this system the combustion of alcohols and glycerol (the largest by-product of biodiesel production), along with other fuels with multiple hydroxyl groups, was studied. Measurements of the mean flame temperature and exhaust gas measurements of NOX showed significant reductions in non-thermal NO concentrations with increasing numbers of OH groups. An accompanying modeling study and detailed reaction path analysis showed that fuel decomposition pathways through formaldehyde were shown a preference due to the presence of the OH groups which resulted in reduced contributions to the hydrocarbon radical pools subsequent reductions to the Prompt NO mechanism. Two burner configurations with reduced dimensionality facilitated

  18. Polar bear maternity denning in the Beaufort Sea

    Science.gov (United States)

    Amstrup, Steven C.; Gardner, Craig L.

    1994-01-01

    The distribution of polar bears (Ursus maritimus) is circumpolar in the NOrthern Hemisphere, but known locations of maternal dens are concentrated in relatively few, widely scattered locations. Denning is either uncommon or unknown within gaps. To understand effects of industrial development and propose increases in hunting, the temporal and spatial distribution of denning in the Beaufort Sea must be known. We caputred and radiocollared polar bears between 1981 and 1991 and determined tht denning in the Beaufort Sea region was sufficient to account for the estimated population there. Of 90 dend, 48 were on drifting pack ice, 38 on land, and 4 on land-fast ice. The portions of dens on land was higher (P= 0.029) in later compared with earlier years of the study. Bears denning on pack ice drifting as far as 997 km (x=385km) while in dens. there was no difference in cun production by bears denning on land and pack ice (P =0.66). Mean entry and exit dates were 11 November and 5 April for land dens and 22 November and 26 March for pack-ice dens. Female polar bears captured in the Beaufort Sea appeared to be isolated from those caught eat of Cape Bathurst in Canada. Of 35 polar bears that denned along the mainland coast of Alaska and Canada 80% denned between 137 00'W snf 146 59'W. Bears followed to >1 den did not reuse sites and consecutive dens were 20-1,304 km apart. However radio-collared bears are largely faithful to substrate (pack-ice, land, and land-fast ice) and the general geographic area of previous dens. Bears denning on land may be vunerable to human activities such as hunting and industrial development. However, predictable denning chronology and alck of site fidelity indicate that many potential impacts on denning polar bears could be mitigated.

  19. Uranium mineralization in the Molteno and Elliot Formations

    International Nuclear Information System (INIS)

    Le Roux, J.P.

    1990-01-01

    To date very little has been published on the uranium deposits of the Molteno and Elliot Formations. Two selected deposits from these formations are described and compared to the uranium occurrences of the Beaufort Group. Whereas the latter are generally confined to channel zones due to the fine grain size and impermeable nature of the host sandstones, uranium in the Molteno and Elliot Formations seems to be concentrated in the less permeable 'island' areas. An apparent association with dolerite sills and dykes also suggests that the host sandstones were still sufficiently permeable after intrusion of the dolorite so that ground waters could remobilize the uranium. This agrees with recently published isotopic ages for the mineralization. There is a distinct possibility that roll-type uranium deposits may be present in the Molteno and Elliot Formations, and any future exploration should bear this in mind. 9 figs., 1 tab., 16 refs

  20. Beaufort Sea deep-water gas hydrate recovery from a seafloor mound in a region of widespread BSR occurrence

    Science.gov (United States)

    Hart, Patrick E.; Pohlman, John W.; Lorenson, T.D.; Edwards, Brian D.

    2011-01-01

    Gas hydrate was recovered from the Alaskan Beaufort Sea slope north of Camden Bay in August 2010 during a U.S. Coast Guard Cutter Healy expedition (USCG cruise ID HLY1002) under the direction of the U.S. Geological Survey (USGS). Interpretation of multichannel seismic (MCS) reflection data collected in 1977 by the USGS across the Beaufort Sea continental margin identified a regional bottom simulating reflection (BSR), indicating that a large segment of the Beaufort Sea slope is underlain by gas hydrate. During HLY1002, gas hydrate was sampled by serendipity with a piston core targeting a steep-sided bathymetric high originally thought to be an outcrop of older, exposed strata. The feature cored is an approximately 1100m diameter, 130 m high conical mound, referred to here as the Canning Seafloor Mound (CSM), which overlies the crest of a buried anticline in a region of sub-parallel compressional folds beneath the eastern Beaufort outer slope. An MCS profile shows a prominent BSR upslope and downslope from the mound. The absence of a BSR beneath the CSM and occurrence of gas hydrate near the summit indicates that free gas has migrated via deep-rooted thrust faults or by structural focusing up the flanks of the anticline to the seafloor. Gas hydrate recovered from near the CSM summit at a subbottom depth of about 5.7 meters in a water depth of 2538 m was of nodular and vein-filling morphology. Although the hydrate was not preserved, residual gas from the core liner contained >95% methane by volume when corrected for atmospheric contamination. The presence of trace C4+hydrocarbons (extrusion contributing to the development of the mound. Blister-like inflation of the seafloor caused by formation and accumulation of shallow hydrate lenses is also a likely factor in CSM growth. Pore water analysis shows the sulfate-methane transition to be very shallow (0-1 mbsf), also supporting an active high-flux interpretation. Pore water with chloride concentrations as low as 160 m

  1. Econometric analyses of microfinance credit group formation, contractual risks and welfare impacts in Northern Ethiopia

    NARCIS (Netherlands)

    Berhane Tesfay, G.

    2009-01-01

    Key words
    Microfinance, joint liability, contractual risk, group formation, risk-matching, impact evaluation, Panel data econometrics, dynamic panel probit, trend models, fixed-effects, composite counterfactuals, propensity score matching, farm households, Ethiopia.

    Lack of

  2. Group Formation Based on Learning Styles: Can It Improve Students' Teamwork?

    Science.gov (United States)

    Kyprianidou, Maria; Demetriadis, Stavros; Tsiatsos, Thrasyvoulos; Pombortsis, Andreas

    2012-01-01

    This work explores the impact of teacher-led heterogeneous group formation on students' teamwork, based on students' learning styles. Fifty senior university students participated in a project-based course with two key organizational features: first, a web system (PEGASUS) was developed to help students identify their learning styles and…

  3. High Charge Mobility of a Perylene Bisimide Dye with Hydrogen-bond Formation Group

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    A perylene bisimide dye covalently bonded with a hydrogen-bond formation group of 1,3, 5-triazine-2, 4-diamine has been synthesized. Its casting films show a charge carrier mobility over 10-3 cm2/Vs, which is in the range of the highest values found for other promising charge transport materials suitable for solution processable technique.

  4. Star Formation Histories of Local Group Dwarf Galaxies. (Ludwig Biermann Award Lecture 1996)

    Science.gov (United States)

    Grebel, E. K.

    The star formation histories of dwarf galaxies in the Local Group are reviewed. First the question of Local Group membership is considered based on various criteria. The properties of 31 (36) galaxies are consistent with likely (potential) Local Group membership. To study the star formation histories of these galaxies, a multi-parameter problem needs to be solved: Ages, metallicities, population fractions, and spatial variations must be determined, which depend crucially on the knowledge of reddening and distance. The basic methods for studying resolvable stellar populations are summarized. One method is demonstrated using the Fornax dwarf spheroidal galaxy. A comprehensive compilation of the star formation histories of dwarf irregulars, dwarf ellipticals, and dwarf spheroidals in the Local Group is presented and visualized through Hodge's population boxes. All galaxies appear to have differing fractions of old and intermediate-age populations, and those sufficiently massive and undisturbed to retain and recycle their gas are still forming stars today. Star formation has occurred either in distinct episodes or continuously over long periods of time. Metallicities and enrichment vary widely. Constraints on merger and remnant scenarios are discussed, and a unified picture based on the current knowledge is presented. Primary goals for future observations are: accurate age determinations based on turnoff photometry, detection of subpopulations distinct in age, metallicity, and/or spatial distribution; improved distances; and astrometric studies to derive orbits and constrain past and future interactions.

  5. Reprocessing of multi-channel seismic-reflection data collected in the Beaufort Sea

    Science.gov (United States)

    Agena, W.F.; Lee, Myung W.; Hart, P.E.

    2000-01-01

    Contained on this set of two CD-ROMs are stacked and migrated multi-channel seismic-reflection data for 65 lines recorded in the Beaufort Sea by the United States Geological Survey in 1977. All data were reprocessed by the USGS using updated processing methods resulting in improved interpretability. Each of the two CD-ROMs contains the following files: 1) 65 files containing the digital seismic data in standard, SEG-Y format; 2) 1 file containing navigation data for the 65 lines in standard SEG-P1 format; 3) an ASCII text file with cross-reference information for relating the sequential trace numbers on each line to cdp numbers and shotpoint numbers; 4) 2 small scale graphic images (stacked and migrated) of a segment of line 722 in Adobe Acrobat (R) PDF format; 5) a graphic image of the location map, generated from the navigation file; 6) PlotSeis, an MS-DOS Application that allows PC users to interactively view the SEG-Y files; 7) a PlotSeis documentation file; and 8) an explanation of the processing used to create the final seismic sections (this document).

  6. New polymers containing BF2-benzoylacetonate groups. Synthesis, luminescence, excimer and exciplex formation

    International Nuclear Information System (INIS)

    Fedorenko, Elena V.; Mirochnik, Anatolii G.; Beloliptsev, Anton Yu.

    2017-01-01

    In the present study, a new synthetic method for the functionalization of polystyrene (PS) and (styrene-methyl methacrylate) copolymer has been developed. Using the new method, polymers containing BF 2 -benzoylacetonate groups have been obtained through double acylation by acetic anhydride with boron trifluoride. Luminescence of the produced polymers in solutions and films has been studied. Quantum yields of polymer solution luminescence are significantly higher than those of the low-molecular-weight analog – boron difluoride benzoylacetonate. For the polymer, in which styrene fragments are separated by methyl methacrylate groups, at low concentrations of the polymer in solution one observes the monomer luminescence of BF 2 -benzoylacetonate groups, while at high concentrations – the excimer luminescence. In case of PS-based polymers, in which BF 2 -benzoylacetonate groups and phenyl rings are not separated, in diluted solutions one observes the fluorescence of the intramolecular exciplexes, while at the concentration increase – the luminescence of intermolecular exciplexes. The ability of excimer formation is responsible for the increased photostability of the produced polymers. - Highlights: •Polymers containing BF 2 -benzoylacetonate groups have been synthesized. •Luminescence of the produced polymers in solutions and films has been studied. •Formation of excimers and exciplexes in solution has been revealed. •Formation of excimers in films increases their photostability.

  7. New polymers containing BF{sub 2}-benzoylacetonate groups. Synthesis, luminescence, excimer and exciplex formation

    Energy Technology Data Exchange (ETDEWEB)

    Fedorenko, Elena V., E-mail: gev@ich.dvo.ru [Institute of Chemistry, Far Eastern Branch of the Russian Academy of Sciences, 159, Prosp. 100 letiya Vladivostoka, Vladivostok 690022 (Russian Federation); Mirochnik, Anatolii G.; Beloliptsev, Anton Yu. [Institute of Chemistry, Far Eastern Branch of the Russian Academy of Sciences, 159, Prosp. 100 letiya Vladivostoka, Vladivostok 690022 (Russian Federation)

    2017-05-15

    In the present study, a new synthetic method for the functionalization of polystyrene (PS) and (styrene-methyl methacrylate) copolymer has been developed. Using the new method, polymers containing BF{sub 2}-benzoylacetonate groups have been obtained through double acylation by acetic anhydride with boron trifluoride. Luminescence of the produced polymers in solutions and films has been studied. Quantum yields of polymer solution luminescence are significantly higher than those of the low-molecular-weight analog – boron difluoride benzoylacetonate. For the polymer, in which styrene fragments are separated by methyl methacrylate groups, at low concentrations of the polymer in solution one observes the monomer luminescence of BF{sub 2}-benzoylacetonate groups, while at high concentrations – the excimer luminescence. In case of PS-based polymers, in which BF{sub 2}-benzoylacetonate groups and phenyl rings are not separated, in diluted solutions one observes the fluorescence of the intramolecular exciplexes, while at the concentration increase – the luminescence of intermolecular exciplexes. The ability of excimer formation is responsible for the increased photostability of the produced polymers. - Highlights: •Polymers containing BF{sub 2}-benzoylacetonate groups have been synthesized. •Luminescence of the produced polymers in solutions and films has been studied. •Formation of excimers and exciplexes in solution has been revealed. •Formation of excimers in films increases their photostability.

  8. SOME ASPECTS OF FORMATION OF FINANCIAL-INDUSTRIAL GROUPS IN RUSSIA IN 1990S

    Directory of Open Access Journals (Sweden)

    Сергей Александрович Лутошкин

    2015-12-01

    Full Text Available The article examines the main stages of the financial-industrial groups formation in Russia in the 1990s, analyzes the main premises of these forms of association in the industrial and financial sectors, as well as the mechanism of their creation under conditions of the transitional market economy. The study revealed the main forms of financial and industrial groups in Russia and the fact that they had a national specificity. The author concludes that the distinctive feature was the formation of Russian business groups mostly from the former nomenklatura and Komsomol workers on the basis of pre-existing material base, which largely contributed to their rapid transformation into large concerns. The state did not prevent the creation of industrial and financial corporations, because of receiving financial support in the form of replenishment of the state budget through tax revenues and revival of production through investments in illiquid corporate enterprises.

  9. Molecularly oriented surface relief formation in polymethacrylates comprising N-benzylideneaniline derivative side groups

    Science.gov (United States)

    Kawatsuki, Nobuhiro; Hosoda, Risa; Kondo, Mizuho; Sasaki, Tomoyuki; Ono, Hiroshi

    2014-12-01

    Molecularly oriented surface relief (SR) formation in polymethacrylates with N-benzylideneaniline (NBA) derivative side groups is investigated by holographic exposure using a 325 nm He-Cd laser. Because the NBA moieties show a photoinduced orientation perpendicular to the polarization of light, polarization holography successfully forms a molecularly oriented SR structure in accordance with the polarization distribution that includes p-polarized components. Although intensity holography induces molecular orientation, it does not generate a satisfactory SR structure. In all the holographic modes, the SR depth depends on the direction of the C=N bonds in the NBA moieties and the photoproducts affect the SR formation ability.

  10. The Ultraviolet and Infrared Star Formation Rates of Compact Group Galaxies: An Expanded Sample

    Science.gov (United States)

    Lenkic, Laura; Tzanavaris, Panayiotis; Gallagher, Sarah C.; Desjardins, Tyler D.; Walker, Lisa May; Johnson, Kelsey E.; Fedotov, Konstantin; Charlton, Jane; Cardiff, Ann H.; Durell, Pat R.

    2016-01-01

    Compact groups of galaxies provide insight into the role of low-mass, dense environments in galaxy evolution because the low velocity dispersions and close proximity of galaxy members result in frequent interactions that take place over extended time-scales. We expand the census of star formation in compact group galaxies by Tzanavaris et al. (2010) and collaborators with Swift UVOT, Spitzer IRAC and MIPS 24 m photometry of a sample of 183 galaxies in 46 compact groups. After correcting luminosities for the contribution from old stellar populations, we estimate the dust-unobscured star formation rate (SFRUV) using the UVOT uvw2 photometry. Similarly, we use the MIPS 24 m photometry to estimate the component of the SFR that is obscured by dust (SFRIR). We find that galaxies which are MIR-active (MIR-red), also have bluer UV colours, higher specific SFRs, and tend to lie in Hi-rich groups, while galaxies that are MIR-inactive (MIR-blue) have redder UV colours, lower specific SFRs, and tend to lie in Hi-poor groups. We find the SFRs to be continuously distributed with a peak at about 1 M yr1, indicating this might be the most common value in compact groups. In contrast, the specific SFR distribution is bimodal, and there is a clear distinction between star-forming and quiescent galaxies. Overall, our results suggest that the specific SFR is the best tracer of gas depletion and galaxy evolution in compact groups.

  11. Dinosaur footprint assemblage from the Lower Cretaceous Khok Kruat Formation, Khorat Group, northeastern Thailand

    Directory of Open Access Journals (Sweden)

    Shohei Kozu

    2017-11-01

    Full Text Available The Khok Kruat Formation is the upper part of the Khorat Group, which consists of upper Lower Cretaceous non-marine sedimentary rocks in northeastern Thailand. Many dinosaur footprints have been known from the upper Lower Cretaceous (Aptian–Albian Khok Kruat Formation at the Huai Dam Chum (Tha Uthen site, northeastern Thailand. Approximately 600 tracks occur in thin mudstone layer of the northern part of the outcrop at the Huai Dam Chum track site. Two types of footprints, small-sized theropod and crocodylomorph are imprinted with mud cracks and ripple marks on the thin mud layer. Most of footprints are referred to cf. Asianopodus, and are imprinted by small-sized theropoda, probably ornithomimosauria. Theropod tracks are mainly separated into two groups, Group A and Group B. From ichnological viewpoints, the small-sized theropod track assemblage indicates the herd behaviour and its idiosyncratic group composition. In particular, the histogram of size-frequency measurements of Group A shows the anomalous bimodal distribution. We consider that there are two hypotheses; the first one is due to the male-female difference, and the second is a result of the different growing stage.

  12. Quaternary sedimentation of the Alaskan Beaufort shelf: Influence of regional tectonics, fluctuating sea levels, and glacial sediment sources

    Science.gov (United States)

    Dinter, D.A.

    1985-01-01

    The offshore stratigraphy of the Quaternary Gubik Formation of Arctic Alaska has been studied on high-resolution seismic profiles with a maximum sub-seafloor penetration of about 100 m. In general, marine transgressive subunits of the Gubik Formation are wedge-shaped on the shelf, thickening slightly seaward to the shelf break, beyond which they are offset by landslides and slumps. Beneath the eastern third of the Alaskan Beaufort shelf, active folding has created two persistent structural depressions, the Eastern and Western Wedge Terranes, in which the wedge morphology is especially well developed. The youngest transgressive marine wedge, which was deposited in such a way as to fill these depressions, leaving a generally flat present-day shelf surface, is inferred to be late Wisconsin or younger in age because it overlies a prominent disconformity interpreted to have been formed during the late Wisconsin glacial sea-level minimum. The thickness of this youngest wedge, Unit A, locally exceeds 40 m on the outer shelf, yet apparently relict gravel deposits collected from its seabed surface indicate that the depositional rate is presently quite low on the middle and outer shelf. Lithologies of the gravels are exotic to Alaska, but similar to suites exposed in the Canadian Arctic Islands. These observations suggest a depositional scenario in which the retreating Laurentide Ice Sheet shed sediment-laden icebergs from the Canadian Arctic Islands into the Arctic Ocean following the late Wisconsin glacial maximum. These bergs were then rafted westward by the Beaufort Gyre and grounded on the Alaskan shelf by northeasterly prevailing winds. Especially large numbers of bergs accumulated in the wedge terrane embayments-created as sea level rose-and melted there, filling the embayments with their sedimentary cargo. As glacial retreat slowed, depositional rates on the shelf dwindled. This mode of deposition in the Alaskan Beaufort wedge terranes may be typical of early post

  13. Controlling formation of single-molecule junctions by electrochemical reduction of diazonium terminal groups.

    Science.gov (United States)

    Hines, Thomas; Díez-Pérez, Ismael; Nakamura, Hisao; Shimazaki, Tomomi; Asai, Yoshihiro; Tao, Nongjian

    2013-03-06

    We report controlling the formation of single-molecule junctions by means of electrochemically reducing two axialdiazonium terminal groups on a molecule, thereby producing direct Au-C covalent bonds in situ between the molecule and gold electrodes. We report a yield enhancement in molecular junction formation as the electrochemical potential of both junction electrodes approach the reduction potential of the diazonium terminal groups. Step length analysis shows that the molecular junction is significantly more stable, and can be pulled over a longer distance than a comparable junction created with amine anchoring bonds. The stability of the junction is explained by the calculated lower binding energy associated with the direct Au-C bond compared with the Au-N bond.

  14. Geochemistry and source of iron-formation from Guanhaes group, Guanhaes district, Minas Gerais, Brazil

    International Nuclear Information System (INIS)

    Sad, J.H.G.; Chiodi Filho, C.; Magalhaes, J.M.M.; Carelos, P.M.

    1990-01-01

    The Guanhaes district is underlain by metavolcano-sedimentary rocks of the Guanhaes Group, emplaced over an older Archean basement and intruded by granitic bodies. The Guanhaes Group is composed of pelitic, mafic and ultramafic schists at the base; silicate and carbonate facies iron-formation, calcarious schists, calcsilicates rocks and quartzites at the median portion and para-gneisses (meta-graywacks) at the top. Geochemistry of iron-formation suggest a hydrothermal affinity comparable to the hydrothermal sediments flanking East Pacific Rise. Paragenetic studies indicates that the rocks were submited to two metamorphic processes: one of regional character (high-amphibolite facies) and one of themal character (pyroxene-hornfels facies). Chemical analysis, as X-ray and optic spectrography, atomic absorption and plasma spectrography are presented. (author)

  15. Mechanism of trans-vinylene groups formation in the radiolysis of polyethylene and n-alkanes

    International Nuclear Information System (INIS)

    Borzov, S.M.; Sukhov, F.F.; Slovokhotova, N.A.

    1984-01-01

    Infrared spectra of polyethylene and some n-alkanes were studied after their irradiation at 20 K with 1-MeV electrons and subsequent heating to 160 K. The mechanism of trans-vinylene groups formation is suggested, which takes into account the decay of excited states of molecules in primary processes and the intra-chain recombination of free radicals in post-irradiation reactions. (author)

  16. Comparing Web, Group and Telehealth Formats of a Military Parenting Program

    Science.gov (United States)

    2016-06-01

    materials are available upon request: • Online questionnaire for baseline data collection (9 pages) • Online parent survey for time point 1 (69 pages...web-based parenting intervention for military families with school-aged children, we expect to strengthen parenting practices in families and...AWARD NUMBER: W81XWH-14-1-0143 TITLE: Comparing Web, Group and Telehealth Formats of a Military Parenting Program PRINCIPAL INVESTIGATOR

  17. Recurring Spring Leads and Landfast Ice in the Beaufort and Chukchi Seas, 1993-2004

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In the Beaufort and Chukchi Seas, the most significant sea ice anomalies have occurred in the summer ice extent (Eicken et al. 2006). In addition, there has been a...

  18. Ice Draft and Ice Velocity Data in the Beaufort Sea, 1990-2003, Version 1

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set provides measurement of sea ice draft (m) and the movement of sea ice (cm/s) over the continental shelf of the Eastern Beaufort Sea. The data set spans...

  19. Modeling plankton ecosystem functioning and nitrogen fluxes in the oligotrophic waters of the Beaufort Sea, Arctic Ocean: a focus on light-driven processes

    Directory of Open Access Journals (Sweden)

    V. Le Fouest

    2013-07-01

    Full Text Available The Arctic Ocean (AO undergoes profound changes of its physical and biotic environments due to climate change. In some areas of the Beaufort Sea, the stronger haline stratification observed in summer alters the plankton ecosystem structure, functioning and productivity, promoting oligotrophy. A one-dimension (1-D physical–biological coupled model based on the large multiparametric database of the Malina project in the Beaufort Sea was used (i to infer the plankton ecosystem functioning and related nitrogen fluxes and (ii to assess the model sensitivity to key light-driven processes involved in nutrient recycling and phytoplankton growth. The coupled model suggested that ammonium photochemically produced from photosensitive dissolved organic nitrogen (i.e., photoammonification process was a necessary nitrogen source to achieve the observed levels of microbial biomass and production. Photoammonification directly and indirectly (by stimulating the microbial food web activity contributed to 70% and 18.5% of the 0–10 m and whole water column, respectively, simulated primary production (respectively 66% and 16% for the bacterial production. The model also suggested that variable carbon to chlorophyll ratios were required to simulate the observed herbivorous versus microbial food web competition and realistic nitrogen fluxes in the Beaufort Sea oligotrophic waters. In face of accelerating Arctic warming, more attention should be paid in the future to the mechanistic processes involved in food webs and functional group competition, nutrient recycling and primary production in poorly productive waters of the AO, as they are expected to expand rapidly.

  20. Interacting star clusters in the Large Magellanic Cloud. Overmerging problem solved by cluster group formation

    Science.gov (United States)

    Leon, Stéphane; Bergond, Gilles; Vallenari, Antonella

    1999-04-01

    We present the tidal tail distributions of a sample of candidate binary clusters located in the bar of the Large Magellanic Cloud (LMC). One isolated cluster, SL 268, is presented in order to study the effect of the LMC tidal field. All the candidate binary clusters show tidal tails, confirming that the pairs are formed by physically linked objects. The stellar mass in the tails covers a large range, from 1.8x 10(3) to 3x 10(4) \\msun. We derive a total mass estimate for SL 268 and SL 356. At large radii, the projected density profiles of SL 268 and SL 356 fall off as r(-gamma ) , with gamma = 2.27 and gamma =3.44, respectively. Out of 4 pairs or multiple systems, 2 are older than the theoretical survival time of binary clusters (going from a few 10(6) years to 10(8) years). A pair shows too large age difference between the components to be consistent with classical theoretical models of binary cluster formation (Fujimoto & Kumai \\cite{fujimoto97}). We refer to this as the ``overmerging'' problem. A different scenario is proposed: the formation proceeds in large molecular complexes giving birth to groups of clusters over a few 10(7) years. In these groups the expected cluster encounter rate is larger, and tidal capture has higher probability. Cluster pairs are not born together through the splitting of the parent cloud, but formed later by tidal capture. For 3 pairs, we tentatively identify the star cluster group (SCG) memberships. The SCG formation, through the recent cluster starburst triggered by the LMC-SMC encounter, in contrast with the quiescent open cluster formation in the Milky Way can be an explanation to the paucity of binary clusters observed in our Galaxy. Based on observations collected at the European Southern Observatory, La Silla, Chile}

  1. Aircraft Surveys of the Beaufort Sea Seasonal Ice Zone

    Science.gov (United States)

    Morison, J.

    2016-02-01

    The Seasonal Ice Zone Reconnaissance Surveys (SIZRS) is a program of repeated ocean, ice, and atmospheric measurements across the Beaufort-Chukchi sea seasonal sea ice zone (SIZ) utilizing US Coast Guard Arctic Domain Awareness (ADA) flights of opportunity. The SIZ is the region between maximum winter sea ice extent and minimum summer sea ice extent. As such, it contains the full range of positions of the marginal ice zone (MIZ) where sea ice interacts with open water. The increasing size and changing air-ice-ocean properties of the SIZ are central to recent reductions in Arctic sea ice extent. The changes in the interplay among the atmosphere, ice, and ocean require a systematic SIZ observational effort of coordinated atmosphere, ice, and ocean observations covering up to interannual time-scales, Therefore, every year beginning in late Spring and continuing to early Fall, SIZRS makes monthly flights across the Beaufort Sea SIZ aboard Coast Guard C-130H aircraft from USCG Air Station Kodiak dropping Aircraft eXpendable CTDs (AXCTD) and Aircraft eXpendable Current Profilers (AXCP) for profiles of ocean temperature, salinity and shear, dropsondes for atmospheric temperature, humidity, and velocity profiles, and buoys for atmosphere and upper ocean time series. Enroute measurements include IR imaging, radiometer and lidar measurements of the sea surface and cloud tops. SIZRS also cooperates with the International Arctic Buoy Program for buoy deployments and with the NOAA Earth System Research Laboratory atmospheric chemistry sampling program on board the aircraft. Since 2012, SIZRS has found that even as SIZ extent, ice character, and atmospheric forcing varies year-to-year, the pattern of ocean freshening and radiative warming south of the ice edge is consistent. The experimental approach, observations and extensions to other projects will be discussed.

  2. Monitoring Beaufort Sea waterfowl and marine birds. Final report

    International Nuclear Information System (INIS)

    Johnson, S.R.

    1990-01-01

    The purpose of the project was to design and implement a monitoring protocol for marine waterbirds in the Jones-Return Islands area of the central Alaska Beaufort Sea. Because of its overwhelming and widespread abundance, relatively sedentary behavior, ease in counting, and the extensive historical database, the oldsquaw duck (Clangula hyemalis) was selected as the focal species for the study. Two null hypotheses were formulated concerning potential changes in the numbers and distribution of oldsquaws in relation to OCS development in the industrial area, compared to a control area (Stockton-Maguire-Flaxman Islands area) located about 50 km to the east. A 9-year historical database (1977 through 1984, and 1989) was analyzed using multivariate techniques to determine which of several predictor variables recorded during past aerial surveys significantly influenced oldsquaw density in the central Alaska Beaufort Sea. Separate analyses were conducted for the complete open-water period, and for the molt period of oldsquaws, when they are flightless and relatively sedentary in the study areas. The results of the two multiple regression analyses indicated that only about 57% and 68%, respectively, of the total amount of variation in oldsquaw density during the two periods could be explained by predictor variables recorded during aerial surveys. Candidate predictor variables were year of study, day of year, time of day, wind speed and direction, habitat, east-west position (study area) of the transect, distance of the transect from a barrier island, water depth beneath the transect, wave height and amount of ice recorded on the transect. Predictor variables associated with habitat, day of the year, time of day of the survey, amount of ice, and wave height recorded on transect during the survey had the most significant effect on oldsquaw density

  3. The time course of perceptual grouping: the role of segregation and shape formation.

    Science.gov (United States)

    Razpurker-Apfeld, Irene; Kimchi, Ruth

    2007-07-01

    The time course of perceptual grouping was examined in two experiments, using a primed matching task. In different conditions, elements were grouped into columns/rows by common lightness, into a shape (triangle/ arrow or square/cross) by common lightness, and into a shape without segregation of elements. The results showed an early and rapid grouping into columns/rows by common lightness and into a shape when no segregation from other elements was involved. Goodness of shape (i.e., triangle/arrow vs. square/cross) had no influence on how early grouping was evident, but the relatively poorer shapes appeared to consolidate with time. In contrast, grouping into a shape that involved segregation and required resolving figure-ground relations between segregated units, as grouping into a shape by common lightness, consumed time, regardless of shape goodness. These results suggest that the time course of grouping varies as a function of the processes involved in it (e.g., segregation and shape formation) and the conditions prevailing for each process.

  4. Rethinking Cysteine Protective Groups: S-Alkylsulfonyl-l-Cysteines for Chemoselective Disulfide Formation.

    Science.gov (United States)

    Schäfer, Olga; Huesmann, David; Muhl, Christian; Barz, Matthias

    2016-12-12

    The ability to reversibly cross-link proteins and peptides grants the amino acid cysteine its unique role in nature as well as in peptide chemistry. We report a novel class of S-alkylsulfonyl-l-cysteines and N-carboxy anhydrides (NCA) thereof for peptide synthesis. The S-alkylsulfonyl group is stable against amines and thus enables its use under Fmoc chemistry conditions and the controlled polymerization of the corresponding NCAs yielding well-defined homo- as well as block co-polymers. Yet, thiols react immediately with the S-alkylsulfonyl group forming asymmetric disulfides. Therefore, we introduce the first reactive cysteine derivative for efficient and chemoselective disulfide formation in synthetic polypeptides, thus bypassing additional protective group cleavage steps. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Influence of carboxyl group formation on ammonia adsorption of NiO-templated nanoporous carbon surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Meng, Long-Yue [Department of Chemistry, Inha University, 100 Inharo, Nam-gu, Incheon 402-751 (Korea, Republic of); Park, Soo-Jin, E-mail: sjpark@inha.ac.kr [Department of Chemistry, Inha University, 100 Inharo, Nam-gu, Incheon 402-751 (Korea, Republic of)

    2012-11-15

    The scope of this work was to control the surface functional groups of nanoporous carbons (NPs) by oxidizing agents (nitric acid and hydrogen peroxide) treatments and to investigate the relation between carboxyl group and ammonia removal efficiency. The NPs were directly prepared from a cation exchange resin by the carbonization of a mixture with Ni acetate at 900 Degree-Sign C. N{sub 2}/-196 Degree-Sign C adsorption, Boehm's titrations, and X-ray photoelectron spectroscopy (XPS) analyzes were employed to confirm the physicochemical properties of NPs. The ammonia removal efficiency was confirmed by temperature programmed desorption (TPD) technique. In the result, the oxygen content of NPs increased after various treatments and the highest content of carboxyl group formation appeared at a 2:3 volume ratio of HNO{sub 3}/H{sub 2}O{sub 2}. It was also found that the oxidation treatment led to an increase in ammonia removal efficiency of NPs, mainly due to an increase of acid oxygen functional groups (such as carboxyl) on NPs surfaces. -- Graphical abstract: The nanoporous carbons were prepared from an exchange resin by the carbonization of a mixture with Ni acetate for ammonia adsorption. Highlights: Black-Right-Pointing-Pointer The carbons were prepared from an exchange resin by the carbonization of a mixture with Ni acetate. Black-Right-Pointing-Pointer The carbon surfaces were modified with HNO{sub 3}/H{sub 2}O{sub 2} solution at different volume radio. Black-Right-Pointing-Pointer The highest content of carboxyl group formation appeared at a 2:3 volume ratio of HNO{sub 3}/H{sub 2}O{sub 2}. Black-Right-Pointing-Pointer The acid oxygen functional groups (such as carboxyl) on carbon surfaces led to an increase in ammonia adsorption.

  6. Aerial Surveys of the Beaufort Sea Seasonal Ice Zone in 2012-2014

    Science.gov (United States)

    Dewey, S.; Morison, J.; Andersen, R.; Zhang, J.

    2014-12-01

    Seasonal Ice Zone Reconnaissance Surveys (SIZRS) of the Beaufort Sea aboard U.S. Coast Guard Arctic Domain Awareness flights were made monthly from May 2012 to October 2012, June 2013 to August 2013, and June 2014 to October 2014. In 2012 sea ice extent reached a record minimum and the SIZRS sampling ranged from complete ice cover to open water; in addition to its large spatial coverage, the SIZRS program extends temporal coverage of the seasonal ice zone (SIZ) beyond the traditional season for ship-based observations, and is a good set of measurements for model validation and climatological comparison. The SIZ, where ice melts and reforms annually, encompasses the marginal ice zone (MIZ). Thus SIZRS tracks interannual MIZ conditions, providing a regional context for smaller-scale MIZ processes. Observations with Air eXpendable CTDs (AXCTDs) reveal two near-surface warm layers: a locally-formed surface seasonal mixed layer and a layer of Pacific origin at 50-60m. Temperatures in the latter differ from the freezing point by up to 2°C more than climatologies. To distinguish vertical processes of mixed layer formation from Pacific advection, vertical heat and salt fluxes are quantified using a 1-D Price-Weller-Pinkel (PWP) model adapted for ice-covered seas. This PWP simulates mixing processes in the top 100m of the ocean. Surface forcing fluxes are taken from the Marginal Ice Zone Modeling and Assimilation System MIZMAS. Comparison of SIZRS observations with PWP output shows that the ocean behaves one-dimensionally above the Pacific layer of the Beaufort Gyre. Despite agreement with the MIZMAS-forced PWP, SIZRS observations remain fresher to 100m than do outputs from MIZMAS and ECCO.2. The shapes of seasonal cycles in SIZRS salinity and temperature agree with MIZMAS and ECCO.2 model outputs despite differences in the values of each. However, the seasonal change of surface albedo is not high enough resolution to accurately drive the PWP. Use of ice albedo

  7. Role of protein-bound carbonyl groups in the formation of advanced glycation endproducts.

    Science.gov (United States)

    Liggins, J; Furth, A J

    1997-08-22

    Several mechanisms have been postulated for the formation of advanced glycation endproducts (AGEs) from glycated proteins; they all feature protein-bound carbonyl intermediates. Using 2,4-dinitrophenylhydrazine (DNPH), we have detected these intermediates on bovine serum albumin, lysozyme and beta-lactoglobulin after in vitro glycation by glucose or fructose. Carbonyls were formed in parallel with AGE-fluorophores, via oxidative Maillard reactions. Neither Amadori nor Heyns products contributed to the DNPH reaction. Fluorophore and carbonyl yields were much enhanced in lipid-associated proteins, but both groups could also be detected in lipid-free proteins. When pre-glycated proteins were incubated in the absence of free sugar, carbonyl groups were rapidly lost in a first-order reaction, while fluorescence continued to develop beyond the 21 days of incubation. Another unexpected finding was that not all carbonyl groups were blocked by aminoguanidine, although there was complete inhibition of reactions leading to AGE-fluorescence. It is suggested that carbonyls acting as fluorophore precursors react readily with aminoguanidine, while others are resistant to this hydrazine, possibly because they are involved in ring closure. Factors influencing the relative rates of acyclisation and hydrazone formation are discussed, together with possible implications for antiglycation therapy.

  8. Alliance group formation: enabling and constraining effects of embeddedness and social capital in strategic technology alliance networks

    NARCIS (Netherlands)

    Duysters, G.M.; Lemmens, C.E.A.V.

    2003-01-01

    The role of embeddedness and social capital in the process of alliance group formation in strategic technology alliance networks is examined. In particular, the social mechanisms that enable and enforce alliance group formation is studies. It is argued that the enabling effect of embeddedness during

  9. Chemoselective Methylation of Phenolic Hydroxyl Group Prevents Quinone Methide Formation and Repolymerization During Lignin Depolymerization

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kwang Ho; Dutta, Tanmoy; Walter, Eric D.; Isern, Nancy G.; Cort, John R.; Simmons, Blake A.; Singh, Seema

    2017-03-30

    Chemoselective blocking of the phenolic hydroxyl (Ar-OH) group by methylation was found to suppress secondary repolymerization and charring during lignin depolymerization. Methylation of Ar-OH prevents formation of reactive quinone methide intermediates, which are partly responsible for undesirable secondary repolymerization reactions. Instead, this structurally modified lignin produces more relatively low molecular weight products from lignin depolymerization compared to unmodified lignin. This result demonstrates that structural modification of lignin is desirable for production of low molecular weight phenolic products. This approach could be directed toward alteration of natural lignification processes to produce biomass more amenable to chemical depolymerization.

  10. Upper Ocean Evolution Across the Beaufort Sea Marginal Ice Zone

    Science.gov (United States)

    Lee, C.; Rainville, L.; Gobat, J. I.; Perry, M. J.; Freitag, L. E.; Webster, S.

    2016-12-01

    The observed reduction of Arctic summertime sea ice extent and expansion of the marginal ice zone (MIZ) have profound impacts on the balance of processes controlling sea ice evolution, including the introduction of several positive feedback mechanisms that may act to accelerate melting. Examples of such feedbacks include increased upper ocean warming though absorption of solar radiation, elevated internal wave energy and mixing that may entrain heat stored in subsurface watermasses (e.g., the relatively warm Pacific Summer and Atlantic waters), and elevated surface wave energy that acts to deform and fracture sea ice. Spatial and temporal variability in ice properties and open water fraction impact these processes. To investigate how upper ocean structure varies with changing ice cover, how the balance of processes shift as a function of ice fraction and distance from open water, and how these processes impact sea ice evolution, a network of autonomous platforms sampled the atmosphere-ice-ocean system in the Beaufort, beginning in spring, well before the start of melt, and ending with the autumn freeze-up. Four long-endurance autonomous Seagliders occupied sections that extended from open water, through the marginal ice zone, deep into the pack during summer 2014 in the Beaufort Sea. Gliders penetrated up to 200 km into the ice pack, under complete ice cover for up to 10 consecutive days. Sections reveal strong fronts where cold, ice-covered waters meet waters that have been exposed to solar warming, and O(10 km) scale eddies near the ice edge. In the pack, Pacific Summer Water and a deep chlorophyll maximum form distinct layers at roughly 60 m and 80 m, respectively, which become increasingly diffuse late in the season as they progress through the MIZ and into open water. Stratification just above the Pacific Summer Water rapidly weakens near the ice edge and temperature variance increases, likely due to mixing or energetic vertical exchange associated with strong

  11. Effect of estradiol on planktonic growth, coaggregation, and biofilm formation of the Prevotella intermedia group bacteria.

    Science.gov (United States)

    Fteita, Dareen; Könönen, Eija; Söderling, Eva; Gürsoy, Ulvi Kahraman

    2014-06-01

    Alterations in the quantity and quality of biofilms at gingival margin are considered to play a role in the initiation and development of pregnancy-related gingivitis. Prevotella intermedia sensu lato is able to consume estradiol, the major sex hormone secreted during pregnancy, in the absence of vitamin K. The aim of the study was to examine the effect of estradiol on the planktonic growth, coaggregation, polysaccharide production, and biofilm formation of the P. intermedia group bacteria, namely P. intermedia, Prevotella nigrescens, and Prevotella pallens. In all experiments, the type strain (ATCC) and a clinical strain (AHN) of P. intermedia, P. nigrescens, and P. pallens were incubated with the concentrations of 0, 30, 90, and 120 nmol/L of estradiol. Planktonic growth was assessed by means of the colony forming unit method, while coaggregation and biofilm formation were assessed by spectrophotometric methods. In the determination of protein and polysaccharide levels, the Bradford and phenol-sulfuric acid methods were used, respectively. P. pallens AHN 9283 and P. nigrescens ATCC 33563 increased their numbers at planktonic stage with increasing estradiol concentrations. In 48-h biofilm tests, elevated protein levels were found for both strains of P. intermedia, and the strains P. nigrescens ATCC 33563 and P. pallens AHN 9283 in the presence of estradiol. The P. intermedia strains also increased the levels of polysaccharide formation in the biofilm. Coaggregation of the P. intermedia group organisms with Fusobacterium nucleatum was enhanced only in P. intermedia AHN 8290. In conclusion, our in vitro experiments indicate that estradiol regulates planktonic growth, coaggregation, polysaccharide production, and biofilm formation characteristics of P. intermedia, P. nigrescens, and P. pallens differently. These results may, at least partly, explain the differences seen in their contribution to the pathogenesis of pregnancy-related gingivitis

  12. Trace metal contamination of Beaufort's Dyke, North Channel, Irish Sea: A legacy of ordnance disposal

    International Nuclear Information System (INIS)

    Callaway, Alexander; Quinn, Rory; Brown, Craig J.; Service, Matthew; Benetti, Sara

    2011-01-01

    Highlights: → Our samples are the first trace metal concentrations taken from the valley of Beaufort's Dyke. → There is no clear trend between concentrations of trace metals in Dyke and NMMP sediments. → Particle transport simulations show dispersal of trace metals from Beaufort's Dyke is possible. → Disposed ordnance may also contribute to contamination of surrounding areas. → These methods could help predict areas at risk of future trace metal contamination as a result of ordnance disposal. - Abstract: Beaufort's Dyke is a disused ordnance disposal ground within the North Channel of the Irish Sea. Over 1 million tonnes of ordnance were disposed of in the dyke over a 40 year period representing a substantial volume of trace metal pollutants introduced to the seabed. Utilising particle transport modelling software we simulated the potential transport of metal particles from Beaufort's Dyke over a 3 month period. This demonstrated that Beaufort's Dyke has the potential to act as a source for trace metal contamination to areas beyond the submarine valley. Trace metal analysis of sediments from the Dyke and surrounding National Marine Monitoring Programme areas demonstrate that the Dyke is not the most contaminated site in the region. Particle transport modelling enables the transport pathways of trace metal contaminants to be predicted. Implementation of the technique in other munitions disposal grounds will provide valuable information for the selection of monitoring stations.

  13. De Beaufort, een aanzienlijke familie tijdens de Republiek, de Bataafs-Franse tijd en het Koninkrijk 1613-1876

    NARCIS (Netherlands)

    Melchers, R.R.J.

    2014-01-01

    In 1613 Pierre de Beaufort aged 18, left the French town of Sedan for the Dutch Republic. At his death in 1661 in Hulst he had become a man of distinction. More than 200 years later on 30 May 1868 his direct descendant Pieter de Beaufort received from the Hoge Raad van Adel (High Court of Nobility)

  14. The effect of oxytocin on group formation and strategic thinking in men.

    Science.gov (United States)

    Aydogan, Gökhan; Jobst, Andrea; Loy, Fabian; Dehning, Sandra; Zill, Peter; Müller, Norbert; Kocher, Martin

    2018-04-01

    Decision-making in groups is a remarkable and decisive element of human societies. Humans are able to organize themselves in groups, engage in collaborative decision-making processes and arrive at a binding agreement, even in the absence of unanimous consent. However, the transfer of decision-making autonomy requires a willingness to deliberately expose oneself to the decisions of others. A lack of trust in the abilities of others or of the underlying decision-making process, i.e. public trust, can lead to a breakdown of organizations in political or economic domains. Recent studies indicate that the biological basis of trust on an individual level is related to Oxytocin, an endogenous neuropeptide and hormone, which is also associated with pro-social behavior and positive conflict resolution. However, little is known about the effects of Oxytocin on the inclination of individuals to form or join groups and to deliberately engage in collaborative decision-making processes. Here, we show that intranasal administration of Oxytocin (n = 60) compared to placebo (n = 60) in males causes an adverse effect on the choice for forming groups in the presence of a competitive environment. In particular, Oxytocin negatively affects the willingness to work collaboratively in a p-Beauty contest game, whereas the effect is most pronounced for participants with relatively high strategic sophistication. Since our data provide initial evidence that Oxytocin has a positive effect on strategic thinking and performance in the p-Beauty contest game, we argue that the adverse effect on group formation might be rooted in an enhanced strategic sophistication of participants treated with Oxytocin. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. Options for integrated resource management in the Mackenzie Delta-Beaufort Sea region

    International Nuclear Information System (INIS)

    Green, J.E.

    1991-02-01

    Examples of consultative activities and environmental protection measures are reviewed which have been employed in the Mackenzie Delta/Beaufort Sea region by one or more petroleum operators to achieve successful integrated land use during the past 20 years. The review illustrates how petroleum operators, in cooperation with local residents and communities, have planned and adapted specific aspects of different projects to address and resolve environmental and community concerns, and provides an overview of the measures that can be employed to achieve integrated land use planning guidelines for future projects. The review focuses on specific groups of renewable resources and the applicable measures that have been used to reduce industrial impacts to these resources which are very important to local residents. Community consultation processes in the planning region have been successfully used by local residents, government, and industry to identify concerns associated with petroleum projects, and to develop appropriate measures to address these concerns. Environmental protection planning measures are described for cultural and historical resources, air quality, noise, freshwater quality, marine water quality, terrain and soils, fisheries, and terrestrial and marine wildlife. General measures as well as specific protection procedures such as the beluga whale protection plan and oil spill contingency plans are discussed. Although some environmental accidents have occurred during petroleum exploration and drilling activities, evidence suggests that petroleum activity has been able to proceed with no detectable long-term impacts to the environment. 30 refs., 1 fig

  16. The star formation histories of local group dwarf galaxies. II. Searching for signatures of reionization

    Energy Technology Data Exchange (ETDEWEB)

    Weisz, Daniel R. [Department of Astronomy, University of California at Santa Cruz, 1156 High Street, Santa Cruz, CA 95064 (United States); Dolphin, Andrew E. [Raytheon Company, 1151 East Hermans Road, Tucson, AZ 85756 (United States); Skillman, Evan D. [Minnesota Institute for Astrophysics, University of Minnesota, 116 Church Street SE, Minneapolis, MN 55455 (United States); Holtzman, Jon [Department of Astronomy, New Mexico State University, Box 30001, 1320 Frenger Street, Las Cruces, NM 88003 (United States); Gilbert, Karoline M.; Dalcanton, Julianne J.; Williams, Benjamin F., E-mail: drw@ucsc.edu [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States)

    2014-07-10

    We search for signatures of reionization in the star formation histories (SFHs) of 38 Local Group dwarf galaxies (10{sup 4} < M{sub *} < 10{sup 9} M{sub ☉}). The SFHs are derived from color-magnitude diagrams using archival Hubble Space Telescope/Wide Field Planetary Camera 2 imaging. Only five quenched galaxies (And V, And VI, And XIII, Leo IV, and Hercules) are consistent with forming the bulk of their stars before reionization, when full uncertainties are considered. Observations of 13 of the predicted 'true fossils' identified by Bovill and Ricotti show that only two (Hercules and Leo IV) indicate star formation quenched by reionization. However, both are within the virial radius of the Milky Way and evidence of tidal disturbance complicates this interpretation. We argue that the late-time gas capture scenario posited by Ricotti for the low mass, gas-rich, and star-forming fossil candidate Leo T is observationally indistinguishable from simple gas retention. Given the ambiguity between environmental effects and reionization, the best reionization fossil candidates are quenched low mass field galaxies (e.g., KKR 25).

  17. Circulation and water properties in the landfast ice zone of the Alaskan Beaufort Sea

    Science.gov (United States)

    Weingartner, Thomas J.; Danielson, Seth L.; Potter, Rachel A.; Trefry, John H.; Mahoney, Andy; Savoie, Mark; Irvine, Cayman; Sousa, Leandra

    2017-09-01

    Moorings, hydrography, satellite-tracked drifters, and high-frequency radar data describe the annual cycle in circulation and water properties in the landfast ice zone (LIZ) of the Alaskan Beaufort Sea. Three seasons, whose duration and characteristics are controlled by landfast ice formation and ablation, define the LIZ: ;winter;, ;break-up;, and ;open-water;. Winter begins in October with ice formation and ends in June when rivers commence discharging. Winter LIZ ice velocities are zero, under-ice currents are weak ( 5 cm s-1), and poorly correlated with winds and local sea level. The along-shore momentum balance is between along-shore pressure gradients and bottom and ice-ocean friction. Currents at the landfast ice-edge are swift ( 35 cm s-1), wind-driven, with large horizontal shears, and potentially unstable. Weak cross-shore velocities ( 1 cm s-1) imply limited exchanges between the LIZ and the outer shelf in winter. The month-long break-up season (June) begins with the spring freshet and concludes when landfast ice detaches from the bottom. Cross-shore currents increase, and the LIZ hosts shallow ( 2 m), strongly-stratified, buoyant and sediment-laden, under-ice river plumes that overlie a sharp, 1 m thick, pycnocline across which salinity increases by 30. The plume salt balance is between entrainment and cross-shore advection. Break-up is followed by the 3-month long open-water season when currents are swift (≥20 cm s-1) and predominantly wind-driven. Winter water properties are initialized by fall advection and evolve slowly due to salt rejection from ice. Fall waters and ice within the LIZ derive from local rivers, the Mackenzie and/or Chukchi shelves, and the Arctic basin.

  18. Scaling observations of surface waves in the Beaufort Sea

    Directory of Open Access Journals (Sweden)

    Madison Smith

    2016-04-01

    Full Text Available Abstract The rapidly changing Arctic sea ice cover affects surface wave growth across all scales. Here, in situ measurements of waves, observed from freely-drifting buoys during the 2014 open water season, are interpreted using open water distances determined from satellite ice products and wind forcing time series measured in situ with the buoys. A significant portion of the wave observations were found to be limited by open water distance (fetch when the wind duration was sufficient for the conditions to be considered stationary. The scaling of wave energy and frequency with open water distance demonstrated the indirect effects of ice cover on regional wave evolution. Waves in partial ice cover could be similarly categorized as distance-limited by applying the same open water scaling to determine an ‘effective fetch’. The process of local wave generation in ice appeared to be a strong function of the ice concentration, wherein the ice cover severely reduces the effective fetch. The wave field in the Beaufort Sea is thus a function of the sea ice both locally, where wave growth primarily occurs in the open water between floes, and regionally, where the ice edge may provide a more classic fetch limitation. Observations of waves in recent years may be indicative of an emerging trend in the Arctic Ocean, where we will observe increasing wave energy with decreasing sea ice extent.

  19. PROBLEM ASPECTS OF FORMATION OF THE LEGAL INSTITUTE OF CONSOLIDATED TAXPAYERS’ GROUPS IN RUSSIA

    Directory of Open Access Journals (Sweden)

    Irina Glazunova

    2017-01-01

    Full Text Available The subject. The article is devoted to the prerequisites of the emergence and essential characteristics of the institution of consolidated taxpayers’ groups in Russia and abroad, revealing of advantages and disadvantages of the legal regulation of the creation and operation of consolidated groups of payers of corporate profits tax, analyzing results and directions of the development of tax consolidation in Russian Federation.The purpose of the article is to identify positive and negative aspects of the functioning of the institution of consolidated taxpayers’ groups in Russia with the establishment of prospects of tax consolidation and the likely directions of its development.The description of the problem field. The development of the world economic system stimulates the emergence of new forms of management, characterized by the enlargement of busi-ness, the pooling of resources of individual enterprises into a single system in order to optimize entrepreneurial activity. These trends are reflected in the development of tax systems of various countries, that is expressed in the formation of institutions of consolidated taxpayers’ groups. Tax consolidation in Russia is a relatively new phenomenon, and it seems necessary to examine this institution from the law enforcement point of view, to evaluate its effectiveness.Methods and methodology. The authors used methods of analysis, synthesis, as well as formal-legal, comparative-legal, historical methods of investigation.Results and the scope of its application. The authors note that the institution of tax consolidation today is presented in the tax systems of most modern countries.The practice of applying the institution of consolidated taxpayers’ groups testifies to the existence of a significant number of advantages and disadvantages of tax consolidation in Russia. The moratorium on the creation of consolidated taxpayers’ groups, due to the contradictory nature of their influence on the

  20. Aperiodic dynamics in a deterministic adaptive network model of attitude formation in social groups

    Science.gov (United States)

    Ward, Jonathan A.; Grindrod, Peter

    2014-07-01

    Adaptive network models, in which node states and network topology coevolve, arise naturally in models of social dynamics that incorporate homophily and social influence. Homophily relates the similarity between pairs of nodes' states to their network coupling strength, whilst social influence causes coupled nodes' states to convergence. In this paper we propose a deterministic adaptive network model of attitude formation in social groups that includes these effects, and in which the attitudinal dynamics are represented by an activato-inhibitor process. We illustrate that consensus, corresponding to all nodes adopting the same attitudinal state and being fully connected, may destabilise via Turing instability, giving rise to aperiodic dynamics with sensitive dependence on initial conditions. These aperiodic dynamics correspond to the formation and dissolution of sub-groups that adopt contrasting attitudes. We discuss our findings in the context of cultural polarisation phenomena. Social influence. This reflects the fact that people tend to modify their behaviour and attitudes in response to the opinions of others [22-26]. We model social influence via diffusion: agents adjust their state according to a weighted sum (dictated by the evolving network) of the differences between their state and the states of their neighbours. Homophily. This relates the similarity of individuals' states to their frequency and strength of interaction [27]. Thus in our model, homophily drives the evolution of the weighted ‘social' network. A precise formulation of our model is given in Section 2. Social influence and homophily underpin models of social dynamics [21], which cover a wide range of sociological phenomena, including the diffusion of innovations [28-32], complex contagions [33-36], collective action [37-39], opinion dynamics [19,20,40,10,11,13,15,41,16], the emergence of social norms [42-44], group stability [45], social differentiation [46] and, of particular relevance

  1. Chemical Evolution and Star Formation History of the Disks of Spirals in Local Group

    Science.gov (United States)

    Yin, J.

    2011-05-01

    Milky Way (MW), M31 and M33 are the only three spiral galaxies in our Local group. MW and M31 have similar mass, luminosity and morphology, while M33 is only about one tenth of MW in terms of its baryonic mass. Detailed theoretical researches on these three spirals will help us to understand the formation and evolution history of both spiral galaxies and Local group. Referring to the phenomenological chemical evolution model adopted in MW disk, a similar model is established to investigate the star formation and chemical enrichment history of these three local spirals. Firstly, the properties of M31 disk are studied by building a similar chemical evolution model which is able to successfully describe the MW disk. It is expected that a simple unified phenomenological chemical evolution model could successfully describe the radial and global properties of both disks. Comparing with the former work, we adopt an extensive data set as model constraints, including the star formation profile of M31 disk derived from the recent UV data of GALEX. The comparison among the observed properties of these two disks displays very interesting similarities in their radial profiles when the distance from the galactic center is expressed in terms of the corresponding scale length. This implies some common processes in their formation and evolution history. Based on the observed data of the gas mass surface density and SFR surface density, the SFR radial profile of MW can be well described by Kennicutt-Schmidt star formation law (K-S law) or modified K-S law (SFR is inversely proportional to the distance from the galactic center), but this is not applicable to the M31 disk. Detailed calculations show that our unified model describes fairly well all the main properties of the MW disk and most properties of M31 disk, provided that the star formation efficiency of M31 disk is adjusted to be twice as large as that of MW disk (as anticipated from the lower gas fraction of M31). However, the

  2. Experimental and Kinetic Investigation of the Influence of OH Groups on NOX Formation

    KAUST Repository

    Bohon, Myles

    2016-01-01

    the differences in NO formation. Measurements of temperature profiles and in-flame species concentrations, utilizing both probed and non-intrusive laser based techniques, allowed for the investigation of NO formation through non-thermal pathways

  3. Correlations and Areal Distribution of the Table Mountain Formation, Stanislaus Group; Central Sierra Nevada, California

    Science.gov (United States)

    Torrez, G.; Carlson, C. W.; Putirka, K. D.; Pluhar, C. J.; Sharma, R. K.

    2011-12-01

    Late Cenozoic evolution of the western Cordillera is a matter of ongoing debate in geologic studies. Volcanic deposits within, and adjacent to the Sierra Nevada have played a significant role in many of these debates. With local faulting coincident with eruption of members of the Stanislaus Group at ca. 38°N, the composition and correlation of these volcanics can greatly aid our understanding of Sierra Nevada tectonics. At the crest of the central Sierra Nevada, 23 trachyandesite lava flows of the Table Mountain Formation, dated at ~10 Ma, cap Sonora Peak. These 23 flows compose the thickest and most complete known stratigraphic section of the Table Mountain Formation in the region. Located ~12 km east of Sonora Peak are 16 flows of trachyandesite at Grouse Meadow. We have collected a detailed set of geochemical and paleomagnetic data for flows of these two sections at Sonora Peak and Grouse Meadows in an attempt to correlate volcanic, paleomagnetic and structural events related to uplift and extension in the Sierra Nevada and the Walker Lane. Correlation of individual flows is possible based on: stratigraphic order, temporal gaps in deposition as determined by paleomagnetic remanence direction and nonconformities, and flow geochemistry. These correlations allow us to infer source localities, flow directions, and temporal changes in flow routes. The large number of flows present at Grouse Meadow provides an additional data set from which to correlate various localities in the region to those units not represented at Sonora Peak. Several flows which occur in the upper portions of the Sonora Peak and Grouse Meadow stratigraphic sections do not correlate between these localities. The causes of stratigraphic discontinuity potentially represent: tectonic isolation across the Sierran Crest, topographic isolation by the emplacement of younger flows, or the combination of the two. Additional to the correlation of individual flows at these localities, this study shows a

  4. The Star Formation History of the Local Group Dwarf Galaxy Leo I

    Science.gov (United States)

    Gallart, Carme; Freedman, Wendy L.; Aparicio, Antonio; Bertelli, Giampaolo; Chiosi, Cesare

    1999-11-01

    We present a quantitative analysis of the star formation history (SFH) of the Local Group dSph galaxy Leo I, from the information in its Hubble Space Telescope [(V-I),I] color-magnitude diagram (CMD). It reaches the level of the oldest main-sequence turnoffs, and this allows us to retrieve the SFH in considerable detail. The method we use is based on comparing, via synthetic CMDs, the expected distribution of stars in the CMD for different evolutionary scenarios with the observed distribution. We consider the SFH to be composed by the SFR(t), the chemical enrichment law Z(t), the initial mass function (IMF), and a function β(f,q) controlling the fraction f and mass ratio distribution q of binary stars. We analyze a set of ~=50 combinations of four Z(t), three IMFs, and more than four β(f,q). For each of them, the best SFR(t) is searched for among ~=6x107 models. The comparison between the observed CMD and the model CMDs is done through χ2ν minimization of the differences in the number of stars in a set of regions of the CMD, chosen to sample stars of different ages or in specific stellar evolutionary phases. We empirically determine the range of χ2ν values that indicate acceptable models for our set of data using tests with models with known SFHs. Our solution for the SFH of Leo I defines a minimum of χ2ν in a well-defined position of the parameter space, and the derived SFR(t) is robust, in the sense that its main characteristics are unchanged for different combinations of the remaining parameters. However, only a narrow range of assumptions for Z(t), IMF, and β(f,q) result in a good agreement between the data and the models, namely, Z=0.0004, a IMF Kroupa et al. or slightly steeper, and a relatively large fraction of binary stars, with f=0.3-0.6, q>0.6, and an approximately flat IMF for the secondaries, or particular combinations of these parameters that would produce a like fraction of similar mass binaries. Most star formation activity (70% to 80

  5. SOCIAL COMPETENCE FORMATION AMONG TEENAGERS FROM HUMANIST TREND MULTIPLE-AGED GROUPS

    Directory of Open Access Journals (Sweden)

    Larisa A. Krapivina

    2015-01-01

    Full Text Available The paper studies the problems of social development of adolescents in multiple-aged groups (MAG.Methods. The methods involve socio-personal approach, consideration of the subject in a certain ideological humanistic orientation, comparative analysis, and comparison of historical facts, the study of social phenomena of different ages, long-term scientific observations, reflections, a retrospective analysis of personal experience.Results. The author describes objective conditions for the uprise of extremist, subcultural youth of multiple-aged groups, and the reasons whence they begin to perform distinctive functions that are specific for teenagers. Options for models of MAG humanistic educational systems formed in Russian and foreign social and pedagogical practice are listed. A complex of pedagogical conditions provided for the formation of social competence of adolescents in multiple-aged associations of humanistic orientation is considered. It has been found that this type of system is characterized by the following features: the principle of voluntary association of people, independence of subjects, rapid adaptation to changing socio-cultural situation, a variety of activities by interests, alternating change of activities, conflict resolution within the team, a high level of team spirit, selfmanagement, the creative nature of educational process, upbringing, socialization and self-realization. A brief description of conditions for development of fundamental human values among adolescents and formation of new specific complicated humanistic human and personal relations in global world is given.Scientific novelty. The author studies the following concepts: educational system of multiple-aged associations, teenager social competence, ambivalent behavior, emotional and moral compass of personality, invisible assets of the team, emergent effect of multiple-aged groups, inter-age communication. It was found that the specificity of MAG educational

  6. ULTRAVIOLET+INFRARED STAR FORMATION RATES: HICKSON COMPACT GROUPS WITH SWIFT AND SPITZER

    International Nuclear Information System (INIS)

    Tzanavaris, P.; Hornschemeier, A. E.; Immler, S.; Gallagher, S. C.; Johnson, K. E.; Reines, A. E.; Gronwall, C.; Hoversten, E.; Charlton, J. C.

    2010-01-01

    We present Swift UVOT ultraviolet (UV; 1600-3000 A) data with complete three-band UV photometry for a sample of 41 galaxies in 11 nearby ( -1 ) Hickson Compact Groups (HCGs) of galaxies. We use UVOT uvw2-band (2000 A) photometry to estimate the dust-unobscured component, SFR UV , of the total star formation rate, SFR TOTAL . We use Spitzer MIPS 24 μm photometry to estimate SFR IR , the component of SFR TOTAL that suffers dust extinction in the UV and is re-emitted in the IR. By combining the two components, we obtain SFR TOTAL estimates for all HCG galaxies. We obtain total stellar mass, M * , estimates by means of Two Micron All Sky Survey K s -band luminosities, and use them to calculate specific star formation rates, SSFR ≡ SFR TOTAL /M * . SSFR values show a clear and significant bimodality, with a gap between low (∼ -11 yr -1 ) and high-SSFR (∼>1.2 x 10 -10 yr -1 ) systems. We compare this bimodality to the previously discovered bimodality in α IRAC , the MIR activity index from a power-law fit to the Spitzer IRAC 4.5-8 μm data for these galaxies. We find that all galaxies with α IRAC ≤ 0 ( >0) are in the high- (low-) SSFR locus, as expected if high levels of star-forming activity power MIR emission from polycyclic aromatic hydrocarbon molecules and a hot dust continuum. Consistent with this finding, all elliptical/S0 galaxies are in the low-SSFR locus, while 22 out of 24 spirals/irregulars are in the high-SSFR locus, with two borderline cases. We further divide our sample into three subsamples (I, II, and III) according to decreasing H I richness of the parent galaxy group to which a galaxy belongs. Consistent with the SSFR and α IRAC bimodality, 12 out of 15 type I (11 out of 12 type III) galaxies are in the high- (low-) SSFR locus, while type II galaxies span almost the full range of SSFR values. We use the Spitzer Infrared Nearby Galaxy Survey (SINGS) to construct a comparison subsample of galaxies that (1) match HCG galaxies in J-band total

  7. The exchange of inorganic carbon on the Canadian Beaufort Shelf

    Science.gov (United States)

    Mol, Jacoba; Thomas, Helmuth; Hu, Xianmin; Myers, Paul G.

    2017-04-01

    The Mackenzie Shelf in the southeastern Beaufort Sea is an area that has experienced large changes in the past several decades as warming, sea-ice loss, and increased river discharge have altered carbon cycling. Upwelling and downwelling events are common on the shelf, caused by strong, fluctuating along-shore winds and resulting cross-shelf Ekman transport. Downwelling carries inorganic carbon and other remineralization products off the shelf and into the deep basin for possible long-term storage in the world oceans. Upwelling carries water high in dissolved inorganic carbon (DIC) and nutrients from the Pacific-origin upper halocline layer (UHL) onto the shelf. Profiles of DIC and total alkalinity (TA) taken in August and September of 2014 are used to investigate the cycling of inorganic carbon on the Mackenzie Shelf. The along-shore and cross-shelf transport of inorganic carbon is quantified using velocity field output from a simulation of the Arctic and Northern Hemisphere Atlantic (ANHA4) configuration of the Nucleus of European Modelling of the Ocean (NEMO) model. A strong upwelling event prior to sampling on the Mackenzie Shelf is analyzed and the resulting influence on the carbonate system, including the saturation state of aragonite and pH levels, is investigated. TA and δ18O are used to examine water mass distributions in the study area and analyze the influence of Pacific Water, Mackenzie River freshwater, and sea-ice melt on carbon dynamics and air-sea fluxes of CO2 in the surface mixed layer. Understanding carbon transfer in this seasonally dynamic environment is key in order to quantify the importance of Arctic shelf regions to the global carbon cycle and to provide a basis for understanding how its role will respond to the aforementioned changes in the regional marine system.

  8. Aspects of the sedimentology of some uranium-bearing sandstones in the Beaufort West area, Cape Province

    International Nuclear Information System (INIS)

    Cole, D.I.

    1980-01-01

    The sedimentology of some uranium-bearing sandstones from the Beaufort Group in the Beaufort West area was studied by use of some 116 vertical profiles measured across and adjacent to 14 mineralized deposits. The vertical profiles consist of 91 field sections and 25 borehole logs. The sandstones are usually multistorey and alternate with a mudstone and/or siltstone succession. The vertical profiles basically consist of a succession of facies. Some 19 facies were recognised within the sandstones on the basis of texture and sedimentary structure. The facies transitions within the sandstone sequence were subjected to a one-step Markov chain analysis. The cumulative thickness of uranium mineralization for each sedimentary facies within the sandstone sequence was measured. Some 99 per cent of the total cumulative thickness occurs within the coarser-grained facies (grain sizes in excess of very fine), which suggests that permeability was an important control on the mineralization. The coarser-grained facies, which mostly represent lower point bar or channel bar deposits near the base of each storey, probably acted as suitable aquifers for the transport of uraniferous solutions. Irregularities in the base of each storey may have interrupted the flow of these solutions and allowed sufficient time for precipitation of the uranium. Carbonaceous debris is frequently associated with the mineralized deposits and most likely acted as an indirect reductant for this precipitation. Mineralization decreases upwards in the sandstone sequence and some 40 per cent of the total cumulative thickness is restricted to the initial storey. The horizontally bedded facies contain a high proportion of the total cumulative thickness of mineralization (45 per cent) and this again may be related to a more abundant content of carbonaceous debris

  9. Basinal analysis of the Ecca and Lowermost Beaufort Beds and associated coal, uranium and heavy mineral beach sand occurrences

    International Nuclear Information System (INIS)

    Ryan, P.J.; Whitfield, G.G.

    1979-01-01

    The regional sediment transport directions, major provenance areas and the controlling palaeotectonic and palaeogeographic frameworks of sedimentation have been reconstructed for the Great Karoo Basin during the Permian. Analyses of this magnitude can be useful in regional exploration programmes for coal, uranium and fossil heavy mineral beach sand deposits. The strong palaeogeographic control on coal deposition is demonstrated by the fact that some of the most important deposits accumulated in topographically low lying areas on the pre-Karoo surface. Such areas formed sheltered environments ideal for the growth and accumulation of organic material. Elsewhere relatively slow rates of subsidence of a broad, protected, low lying delta plain controlled the deposition of coal. North of the main Karoo Basin many of the coal deposits are confined to structurally controlled linear basins. Hundreds of sedimentary uranium occurrences of varying grade and size occur within a broad, discontinuous belt in the Lower Beaufort of the southwestern portion of the Karoo Basin. The uranium mineralization occurs in a variety of fluvial deposits usually rich in carbonaceous material. Minute tuffaceous fragments, reflecting contemporaneous vulcanism, form a minor but significant constituent in some of the uraniferous sandstones. The uranium occurrences are confined largely to the Southern and Western Facies of the Lower Beaufort, and occur mainly within the confines of the Karoo Trough. Consolidated heavy mineral beach deposits have been found in the predominantly fluvio-deltaic Middle Ecca Group of the Northern Facies at a number of widely separated locations. These deposits were formed by shore line processes, such as the reworking of delta-front sands, during periods of temporary marine regression

  10. Gibbs Free Energy of Formation for Selected Platinum Group Minerals (PGM

    Directory of Open Access Journals (Sweden)

    Spiros Olivotos

    2016-01-01

    Full Text Available Thermodynamic data for platinum group (Os, Ir, Ru, Rh, Pd and Pt minerals are very limited. The present study is focused on the calculation of the Gibbs free energy of formation (ΔfG° for selected PGM occurring in layered intrusions and ophiolite complexes worldwide, applying available experimental data on their constituent elements at their standard state (ΔG = G(species − ΔG(elements, using the computer program HSC Chemistry software 6.0. The evaluation of the accuracy of the calculation method was made by the calculation of (ΔGf of rhodium sulfide phases. The calculated values were found to be ingood agreement with those measured in the binary system (Rh + S as a function of temperature by previous authors (Jacob and Gupta (2014. The calculated Gibbs free energy (ΔfG° followed the order RuS2 < (Ir,OsS2 < (Pt, PdS < (Pd, PtTe2, increasing from compatible to incompatible noble metals and from sulfides to tellurides.

  11. Examining the Center: Positions, Dominance, and Star Formation Rates of Most Massive Group Galaxies at Intermediate Redshift

    Science.gov (United States)

    Connelly, Jennifer L.; Parker, Laura C.; McGee, Sean; Mulchaey, John S.; Finoguenov, Alexis; Balogh, Michael; Wilman, David; Group Environment Evolution Collaboration

    2015-01-01

    The group environment is believed to be the stage for many galaxy transformations, helping evolve blue star-forming galaxies to red passive ones. In local studies of galaxy clusters, the central member is usually a single dominant giant galaxy at the center of the potential with little star formation thought to be the result of galaxy mergers. In nearby groups, a range of morphologies and star formation rates are observed and the formation history is less clear. Further, the position and dominance of the central galaxy cannot be assumed in groups, which are less massive and evolved than clusters. To understand the connections between global group properties and properties of the central group galaxy at intermediate redshift, we examine galaxy groups from the Group Environment and Evolution Collaboration (GEEC) catalog, including both optically- and X-ray-selected groups at redshift z~0.4. The sample is diverse, containing a range in overall mass and evolutionary state. The number of groups is significant, membership is notably complete, and measurements span the IR to the UV allowing the properties of the members to be connected to those of the host groups. Having investigated trends in the global group properties previously, including mass and velocity substructure, we turn our attention now to the galaxy populations, focusing on the central regions of these systems. The most massive and second most massive group galaxies are identified by their stellar mass. The positions of the most massive galaxies (MMGs) are determined with respect to both the luminosity-weighted and X-ray center. Star formation rates are used to explore the fraction of passive/quiescent versus star-forming MMGs and the dominance of the MMGs in our group sample is also tested. Determinations of these characteristics and trends constitute the important first steps toward a detailed understanding of the relationships between the properties of host groups and their most massive galaxies and the

  12. Effectiveness of emotional skills training for patients with anorexia nervosa with autistic symptoms in group and individual format.

    Science.gov (United States)

    Adamson, James; Leppanen, Jenni; Murin, Marianna; Tchanturia, Kate

    2018-04-02

    The aim of this study was to examine the effectiveness of CREST interventions in individual and group formats for adult anorexia nervosa. Furthermore, this study also aims to analyse whether patients with high levels of autistic symptoms respond differently. Participants' self-report measures were taken before and after individual and group interventions (N = 66 and N = 62, respectively). Mixed effects analysis was used to analyse overall response to both formats and assess interaction with autism symptoms. Significant improvements were observed for patients' alexithymia in individual format, and motivation increased for participants in both interventions. Significant interactions were observed between alexithymia, social anhedonia, and autism symptoms in individual format and alexithymia in group format. No interactions between autism and time were observed for either format. CREST in both formats offers participants improvements in social-emotional and motivational domains. Patients with high levels of autism symptoms also score high on both social anhedonia and alexithymia measures, but this does not affect their response to treatment. Copyright © 2018 John Wiley & Sons, Ltd and Eating Disorders Association.

  13. Proton NMR study of the influence of heme vinyl groups on the formation of the isomeric forms of sulfmyoglobin

    International Nuclear Information System (INIS)

    Chatfield, M.J.; La Mar, G.N.; Balch, A.L.; Smith, K.M.; Parish, D.W.; LePage, T.J.

    1986-01-01

    The formation of sulfmyoglobin has been investigated for myoglobin reconstituted with hemins having vinyls replaced by hydrogens to determine the participation of the vinyl groups in the reaction processes. Green complexes are produced in all cases, proving that vinyls are not obligatory for the formation of sulfproteins. In the presence of the 4-vinyl group, the 1 H NMR spectra of the met-cyano derivatives indicate the formation of three green species; however, the most stable of these products is not formed in the absence of this group, confirming reaction of the 4-vinyl in this species. Two new red extractable sulfmyoglobin derivatives are formed in the absence of the 4-vinyl group. (Auth.)

  14. Permian plants from the Chutani Formation (Titicaca Group, Northern Altiplano of Bolivia: II. The morphogenus Glossopteris

    Directory of Open Access Journals (Sweden)

    Roberto Iannuzzi

    2004-03-01

    Full Text Available Fossil plants belonging to the morphogenera Glossopteris, Pecopteris and Asterotheca were collected from the upper part of the Chutani Formation (Titicaca Group, near the town of San Pablo de Tiquina, on the southeastern shore of Lake Titicaca (northern Altiplano, Bolivia. This paper presents the first description of specimens of the morphogenus Glossopteris from Bolivia. The Bolivian specimens of Glossopteris consist of poorly-preserved impressions, although they present the diagnostic features of this morphogenus. They are fragments of leaves with secondary veins of taeniopterid-type, typical of glossopterids from Late Permian deposits of Gondwana. The only species of Pecopteris confirmed in the first part of this study, i.e. P. dolianitii Rösler and Rohn (see Vieira et al. 2004, was previously reported from the Late Permian beds of the Rio do Rasto and Estrada Nova formations in the Paraná Basin (southern Brazil. Therefore, a Late Permian age is proposed for the fossil plant-bearing beds of the Chutani Formation based on the analyzed assemblage. The phytogeographic implications of this new find are briefly analyzed.Plantas fósseis, pertencentes aos morfo-gêneros Glossopteris, Pecopteris e Asterotheca, foram coletadas na porção superior da seção aflorante da Formação Chutani, próxima ao povoado de San Pablo de Tiquina, sudeste do lago Titicaca (Altiplano norte, Bolívia. Este trabalho apresenta a primeira descrição de espécimes do morfo-gênero Glossopteris provenientes da Bolívia. Os espécimes estudados de Glossopteris consistem em impressões foliares pobremente preservadas nas quais feições diagnósticas estão presentes. Os fragmentos foliares apresentam venação secundária do tipo teniopteróide, uma característica típica de glossopterídeas encontradas em depósitos do Permiano Superior do Gondwana. Por sua vez, a única espécie de Pecopteris confirmada para estes níveis da Formação Chutani, i.e. P. dolianitii

  15. Models of talik, permafrost and gas hydrate histories - Beaufort Mackenzie Basin, Canada

    Czech Academy of Sciences Publication Activity Database

    Majorowicz, J.; Osadetz, K.; Šafanda, Jan

    2015-01-01

    Roč. 8, č. 7 (2015), s. 6738-6764 ISSN 1996-1073 Institutional support: RVO:67985530 Keywords : gas hydrates * permafrost * Beaufort-Mackenzie Basin * taliks Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 2.077, year: 2015

  16. Ice Draft and Ice Velocity Data in the Beaufort Sea, 1990-2003

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set provides measurement of sea ice draft (m) and the movement of sea ice (cm/s) over the continental shelf of the Eastern Beaufort Sea. The data set spans...

  17. De Beaufort, een aanzienlijke familie tijdens de Republiek, de Bataafs-Franse tijd en het Koninkrijk 1613-1876

    OpenAIRE

    Melchers, R.R.J.

    2014-01-01

    In 1613 Pierre de Beaufort aged 18, left the French town of Sedan for the Dutch Republic. At his death in 1661 in Hulst he had become a man of distinction. More than 200 years later on 30 May 1868 his direct descendant Pieter de Beaufort received from the Hoge Raad van Adel (High Court of Nobility) a diploma signed by King Willem I in which he was raised to the peerage. This elevation indicates that Pieter de Beaufort belonged to the prominent families of the country. The patent of nobility r...

  18. Prediction of Gibbs energies of formation and stability constants of some secondary uranium minerals containing the uranyl group

    International Nuclear Information System (INIS)

    Genderen, A.C.G. van; Weijden, C.H. van der

    1984-01-01

    For a group of minerals containing a common anion there exists a linear relationship between two parameters called ΔO and ΔF.ΔO is defined as the difference between the Gibbs energy of formation of a solid oxide and the Gibbs energy of formation of its aqueous cation, while ΔF is defined as the Gibbs energy of reaction of the formation of a mineral from the constituting oxide(s) and the acid. Using the Gibbs energies of formation of a number of known minerals the corresponding ΔO's and ΔF's were calculated and with the resulting regression equation it is possible to predict values for the Gibbs energies of formation of other minerals containing the same anion. This was done for 29 minerals containing the uranyl-ion together with phosphate, vanadate, arsenate or carbonate. (orig.)

  19. Stimulation of Changes, Collective Commitment and The Patterns of Group Formation in Community Development in South Sulawesi

    Science.gov (United States)

    Saleh, Syafiuddin

    2018-05-01

    This study aims to examine the pattern of group formation, related to the stimulation of change through the empowerment of farmers and poor fishermen The pattern of group formation is the basis for sustainable development. The research method used is qualitative descriptive method and relevant research type such as case study and triangulasi. The results of the study showed that (1) stimulation of changes made through development programs or community empowerment in the areas studied both among farm households and poor fishermen households for some programs received positive response from farmers and fishermen. However, the collective commitment to the breeding is relatively weak, since the group formed in each program is not done through good planning and concepts. (2) there are two patterns of group formation that are natural and formed formations initiated by outsiders. Groups that are naturally formed are more institutionalized and have characteristics such as intense and relatively routine interaction, strong mutual trust, and have a common form or mechanism shared for common purposes. The group can form the basis for sustainable development in improving the welfare of the poor.

  20. Stopover ecology of Semipalmated Sandpipers (Calidris pusilla) at coastal deltas of the Beaufort Sea, Alaska

    Science.gov (United States)

    Churchwell, Roy T.

    Avian migration is one of the wonders of the natural world. Stored fats are the main source of nutrients and fuel for avian migration and it is assumed the fat deposition at stopover sites is a critical component of a successful migration. Stopover sites are crucial in the successful migration of many birds, but particularly for arctic-breeding shorebirds that migrate long distances from breeding to wintering grounds. Despite the importance of stopover sites, it is often difficult to determine the importance of these sites to migrating shorebirds. I investigated three aspects of stopover ecology of Semipalmated Sandpipers (Calidris pusilla) foraging at coastal deltas on the Beaufort Sea coast, Alaska. First, I quantified the spatial and temporal distribution and abundance of the benthic macroinvertebrate community living within the mudflats. I found that there were two ecological groups of macroinvertebrates using river deltas, one originated in terrestrial freshwater habitats and most importantly could withstand freezing in delta sediments over the winter, and the other originated from the marine environment, could not withstand freezing and had to migrate to intertidal habitats each summer from deeper water areas that did not freeze over the winter. Stable isotope analysis allowed me to describe the origin of carbon consumed by invertebrates in intertidal habitats. I predicted freshwater invertebrates would consume terrestrial carbon, and marine invertebrates would consume marine carbon, but I found that both groups utilized the same carbon, which was a mixture of terrestrial and marine sources. My second research question determined the importance of delta foraging habitat for fall migrating Semipalmated Sandpipers. I mapped the temporal distribution and abundance of birds and quantified this relationship to invertebrate distribution and abundance. I researched fattening rates of shorebirds by measuring triglycerides in the blood of shorebirds I captured. I

  1. Polar Bear Population Status in the Southern Beaufort Sea

    Science.gov (United States)

    Regehr, Eric V.; Amstrup, Steven C.; Stirling, Ian

    2006-01-01

    Polar bears depend entirely on sea ice for survival. In recent years, a warming climate has caused major changes in the Arctic sea ice environment, leading to concerns regarding the status of polar bear populations. Here we present findings from long-term studies of polar bears in the southern Beaufort Sea (SBS) region of the U.S. and Canada, which are relevant to these concerns. We applied open population capture-recapture models to data collected from 2001 to 2006, and estimated there were 1,526 (95% CI = 1,211; 1,841) polar bears in the SBS region in 2006. The number of polar bears in this region was previously estimated to be approximately 1,800. Because precision of earlier estimates was low, our current estimate of population size and the earlier ones cannot be statistically differentiated. For the 2001-06 period, the best fitting capture-recapture model provided estimates of total apparent survival of 0.43 for cubs of the year (COYs), and 0.92 for all polar bears older than COYs. Because the survival rates for older polar bears included multiple sex and age strata, they could not be compared to previous estimates. Survival rates for COYs, however, were significantly lower than estimates derived in earlier studies (P = 0.03). The lower survival of COYs was corroborated by a comparison of the number of COYs per adult female for periods before (1967-89) and after (1990-2006) the winter of 1989-90, when warming temperatures and altered atmospheric circulation caused an abrupt change in sea ice conditions in the Arctic basin. In the latter period, there were significantly more COYs per adult female in the spring (P = 0.02), and significantly fewer COYs per adult female in the autumn (P adult males captured from 1990 to 2006 were smaller than those captured before 1990. The smaller stature of males was especially notable because it corresponded with a higher mean age of adult males. Male polar bears continue to grow into their teens, and if adequately nourished

  2. The Formation of Group Affect and Team Effectiveness : The Moderating Role of Identification

    NARCIS (Netherlands)

    Tanghe, Jacqueline; Wisse, Barbara; van der Flier, Henk

    In the current research we use the social identity perspective to enhance our understanding of group affect (i.e. a collectively shared pattern of affective states among group members). Because higher identification (i.e. the extent to which group members define themselves in terms of their group

  3. SBI AWS02-I CTD Data collected from the Polar Star in the Beaufort and Chukchi Seas (NODC Accession 0001290)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The field phase of the Shelf-Basin Interactions Experiment (SBI) began in 2002 with a series of three cruises to the Chukchi and Beaufort Seas. SBI is a...

  4. EFFLUENT - DISCHARGE DESCRIPTION and Other Data from NOAA LAUNCHES From Beaufort Sea from 19890804 to 19890820 (NODC Accession 9100109)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The chemical data in this accession was collected as part of the the Beaufort Sea Monitoring Program. The data was collected between August 4 and August 20, 1989...

  5. AFSC/NMML: Passive acoustic sonobuoy recordings from Bering, Chukchi, and Beaufort Seas in Alaska, 2007-2014

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The National Marine Mammal Laboratory (NMML) has conducted passive acoustic monitoring in the Bering, Chukchi, and Western Beaufort Seas to determine spatio-temporal...

  6. Theoretical predictions of hydrolysis and complex formation of group-4 elements Zr, Hf and Rf in HF and HCl solutions

    International Nuclear Information System (INIS)

    Pershina, V.; Trubert, D.; Le Naour, C.; Kratz, J.V.

    2002-01-01

    Fully relativistic molecular density-functional calculations of the electronic structures of hydrated, hydrolyzed and fluoride/chloride complexes have been performed for group-4 elements Zr, Hf, and element 104, Rf. Using the electronic density distribution data, relative values of the free energy change for hydrolysis and complex formation reactions were defined. The results show the following trend for the first hydrolysis step of the cationic species: Zr>Hf>Rf in agreement with experiments. For the complex formation in HF solutions, the trend to a decrease from Zr to Hf is continued with Rf, provided no hydrolysis takes place. At pH>0, further fluorination of hydrolyzed species or fluoro-complexes has an inversed trend in the group Rf≥Zr>Hf, with the difference between the elements being very small. For the complex formation in HCl solutions, the trend is continued with Rf, so that Zr>Hf>Rf independently of pH. A decisive energetic factor in hydrolysis or complex formation processes proved to be a predominant electrostatic metal-ligand interaction. Trends in the K d (distribution coefficient) values for the group-4 elements are expected to follow those of the complex formation

  7. Automatic Feature Selection and Weighting for the Formation of Homogeneous Groups for Regional Intensity-Duration-Frequency (IDF) Curve Estimation

    Science.gov (United States)

    Yang, Z.; Burn, D. H.

    2017-12-01

    Extreme rainfall events can have devastating impacts on society. To quantify the associated risk, the IDF curve has been used to provide the essential rainfall-related information for urban planning. However, the recent changes in the rainfall climatology caused by climate change and urbanization have made the estimates provided by the traditional regional IDF approach increasingly inaccurate. This inaccuracy is mainly caused by two problems: 1) The ineffective choice of similarity indicators for the formation of a homogeneous group at different regions; and 2) An inadequate number of stations in the pooling group that does not adequately reflect the optimal balance between group size and group homogeneity or achieve the lowest uncertainty in the rainfall quantiles estimates. For the first issue, to consider the temporal difference among different meteorological and topographic indicators, a three-layer design is proposed based on three stages in the extreme rainfall formation: cloud formation, rainfall generation and change of rainfall intensity above urban surface. During the process, the impacts from climate change and urbanization are considered through the inclusion of potential relevant features at each layer. Then to consider spatial difference of similarity indicators for the homogeneous group formation at various regions, an automatic feature selection and weighting algorithm, specifically the hybrid searching algorithm of Tabu search, Lagrange Multiplier and Fuzzy C-means Clustering, is used to select the optimal combination of features for the potential optimal homogenous groups formation at a specific region. For the second issue, to compare the uncertainty of rainfall quantile estimates among potential groups, the two sample Kolmogorov-Smirnov test-based sample ranking process is used. During the process, linear programming is used to rank these groups based on the confidence intervals of the quantile estimates. The proposed methodology fills the gap

  8. Social factors shaping the formation of a multi-stakeholder trails network group for the Monongahela National Forest, West Virginia

    Science.gov (United States)

    Karen Robinson; Steven Selin; Chad Pierskalla

    2009-01-01

    This paper reports the results and management implications of a longitudinal research study examining the social factors affecting the formation of a trails network advisory group for the Monongahela National Forest (MNF) in West Virginia. A collaborative process of creating an MNF trails network with input from local users and stakeholders has been largely...

  9. The Emergence of Embedded Relations and Group Formation in Networks of Competition

    Science.gov (United States)

    Thye, Shane R.; Lawler, Edward J.; Yoon, Jeongkoo

    2011-01-01

    This study examines how and when small networks of self-interested agents generate a group tie or affiliation at the network level. A group affiliation is formed when actors (a) perceive themselves as members of a group and (b) share resources with each other despite an underlying competitive structure. We apply a concept of structural cohesion to…

  10. Submarine slope failures in the Beaufort Sea; Influence of gas hydrate decomposition

    Science.gov (United States)

    Grozic, J. L.; Dallimore, S.

    2012-12-01

    The continental shelf of the Beaufort Sea is composed of complex of marine and non-marine sequences of clay, silt, and sand. In many areas of the shelf these sediments contain occurrences of ice-bonded permafrost and associated pressure and temperature conditions that are conducive to the occurrence of methane gas hydrates. This complex environment is undergoing dramatic warming, where changes in sea level, ocean bottom temperatures, and geothermal regimes are inducing permafrost thawing and gas hydrate decomposition. Decomposition is inferred to be occurring at the base and top of the gas hydrate stability zone, which will cause sediment weakening and the generation of excess water and free gas. In such settings, the overlying permafrost cap may act as a permeability barrier, which could result in significant excess pore pressures and reduction in sediment stability. The shelf to slope transition is thought to be an area of extensive regional instability with acoustic records indicating there is upwards of 500 km of slumps and glides extending over the entire Beaufort margin. Some of these slide regions are coincident with up-dip limit of the permafrost gas hydrate stability zone. In this paper, a two dimensional model of the Beaufort shelf was constructed to examine the influence of gas hydrate decomposition on slope stability. The model relies on available data on the Beaufort sediments generated from offshore hydrocarbon exploration in the 1980s and 90s, as well as knowledge available from multidisciplinary marine research programs conducted in the outer shelf area. The slope stability model investigates the influence of marine transgression and ocean bottom warming by coupling soil deformation with hydrate dissociation during undrained conditions. By combining mechanical and thermal loading of the sediment, a more accurate indication of slope stability was obtained. The stability analysis results indicate a relatively low factor of safety for the Beaufort

  11. Marine fish community structure and habitat associations on the Canadian Beaufort shelf and slope

    Science.gov (United States)

    Majewski, Andrew R.; Atchison, Sheila; MacPhee, Shannon; Eert, Jane; Niemi, Andrea; Michel, Christine; Reist, James D.

    2017-03-01

    Marine fishes in the Canadian Beaufort Sea have complex interactions with habitats and prey, and occupy a pivotal position in the food web by transferring energy between lower- and upper-trophic levels, and also within and among habitats (e.g., benthic-pelagic coupling). The distributions, habitat associations, and community structure of most Beaufort Sea marine fishes, however, are unknown thus precluding effective regulatory management of emerging offshore industries in the region (e.g., hydrocarbon development, shipping, and fisheries). Between 2012 and 2014, Fisheries and Oceans Canada conducted the first baseline survey of offshore marine fishes, their habitats, and ecological relationships in the Canadian Beaufort Sea. Benthic trawling was conducted at 45 stations spanning 18-1001 m depths across shelf and slope habitats. Physical oceanographic variables (depth, salinity, temperature, oxygen), biological variables (benthic chlorophyll and integrated water-column chlorophyll) and sediment composition (grain size) were assessed as potential explanatory variables for fish community structure using a non-parametric statistical approach. Selected stations were re-sampled in 2013 and 2014 for a preliminary assessment of inter-annual variability in the fish community. Four distinct fish assemblages were delineated on the Canadian Beaufort Shelf and slope: 1) Nearshore-shelf: 50 and ≤200 m depths, 3) Upper-slope: ≥200 and ≤500 m depths, and 4) Lower-slope: ≥500 m depths. Depth was the environmental variable that best explained fish community structure, and each species assemblage was spatially associated with distinct aspects of the vertical water mass profile. Significant differences in the fish community from east to west were not detected, and the species composition of the assemblages on the Canadian Beaufort Shelf have not changed substantially over the past decade. This community analysis provides a framework for testing hypotheses regarding the trophic

  12. Star-Formation Histories, Abundances, and Kinematics of Dwarf Galaxies in the Local Group

    NARCIS (Netherlands)

    Tolstoy, Eline; Hill, Vanessa; Tosi, Monica; Blandford, R; Kormendy, J; VanDishoeck, E

    2009-01-01

    Within the Local Universe galaxies can be studied in great detail star by star, and here we review the results of quantitative studies in nearby dwarf galaxies. The color-magnitude diagram synthesis method is well established as the most accurate way to determine star-formation histories of galaxies

  13. Stratigraphy and correlation of the Manitou Falls formation, the Athabasca Group

    International Nuclear Information System (INIS)

    Iida, Yoshimasa; Ikeda, Koki; Tsuruta, Tadahiko; Yamada, Yasuo; Ito, Hiroaki; Goto, Junichi

    1996-01-01

    Manitou Falls formation is the thick strata of Proterozoic era that spread widely in the uranium deposit zone in Northern Saskatchewan, Canada (Athabasca basin). In order to study in detail underground geological structure by trial boring, it is necessary to distinguish and compare strata by dividing them into the units as small as possible. The Manitou Falls formation is composed of only sandstone and conglomerate, and it does not have simply identified, continuous strata like tuff and coal layers. In the Christie Lake B district located in Eastern Athabasca basin, the division of strata was carried out by utilizing the data of the changes in the volume ratio of conglomerate layer and maximum pebble size and natural radioactivity logging and based on the careful comparison among trial bores. As the result, this formation was divided into the units of 9 strata. As one of the methods of identifying each unit, the comparison of the power spectra of natural radioactivity logging data was attempted. By this means, it was found that the features in the periodicity of stratum accumulation are useful for identifying strata. The outline of the Manitou Falls formation, the location of the investigated district, the basic data for stratigraphy division, the stratigraphy division in Christie Lake B district and the results are reported. (K.I.)

  14. An Agent-Based Simulation for Investigating the Impact of Stereotypes on Task-Oriented Group Formation

    Science.gov (United States)

    Maghami, Mahsa; Sukthankar, Gita

    In this paper, we introduce an agent-based simulation for investigating the impact of social factors on the formation and evolution of task-oriented groups. Task-oriented groups are created explicitly to perform a task, and all members derive benefits from task completion. However, even in cases when all group members act in a way that is locally optimal for task completion, social forces that have mild effects on choice of associates can have a measurable impact on task completion performance. In this paper, we show how our simulation can be used to model the impact of stereotypes on group formation. In our simulation, stereotypes are based on observable features, learned from prior experience, and only affect an agent's link formation preferences. Even without assuming stereotypes affect the agents' willingness or ability to complete tasks, the long-term modifications that stereotypes have on the agents' social network impair the agents' ability to form groups with sufficient diversity of skills, as compared to agents who form links randomly. An interesting finding is that this effect holds even in cases where stereotype preference and skill existence are completely uncorrelated.

  15. Lithostratigraphy of the Calico Hills Formation and Prow Pass Tuff (Crater Flat Group) at Yucca Mountain, Nevada

    International Nuclear Information System (INIS)

    Moyer, T.C.; Geslin, J.K.

    1995-01-01

    Lithostratigraphic relations within the Calico Hills Formation and Prow Pass Tuff (Crater Flat Group) were reconstructed from analysis of core samples and observation of outcrop exposures. The Calico Hills Formation is composed of five nonwelded pyroclastic units (each formed of one or more pyroclastic-flow deposits) that overlie an interval of bedded tuff and a basal volcaniclastic sandstone unit. The Prow Pass Tuff is divided into four pyroclastic units and an underlying interval of bedded tuff. The pyroclastic units of the Prow Pass Tuff are distinguished by the sizes and amounts of their pumice and lithic clasts and their degree of welding. Pyroclastic units of the Prow Pass Tuff are distinguished from those of the Calico Hills Formation by their phenocryst assemblage, chemical composition, and ubiquitous siltstone lithic clasts. Downhole resistivity tends to mirror the content of authigenic minerals, primarily zeolites, in both for-mations and may be useful for recognizing the vitric-zeolite boundary in the study area. Maps of zeolite distribution illustrate that the bedded tuff and basal sandstone units of the Calico Hills Formation are altered over a wider area than the pyroclastic units of both the Calico Hills Formation and the upper Prow Pass Tuff

  16. Lithostratigraphy of the Calico Hills Formation and Prow Pass Tuff (Crater Flat Group) at Yucca Mountain, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Moyer, T.C.; Geslin, J.K. [Science Applications International Corp., Las Vegas, NV (United States)

    1995-07-01

    Lithostratigraphic relations within the Calico Hills Formation and Prow Pass Tuff (Crater Flat Group) were reconstructed from analysis of core samples and observation of outcrop exposures. The Calico Hills Formation is composed of five nonwelded pyroclastic units (each formed of one or more pyroclastic-flow deposits) that overlie an interval of bedded tuff and a basal volcaniclastic sandstone unit. The Prow Pass Tuff is divided into four pyroclastic units and an underlying interval of bedded tuff. The pyroclastic units of the Prow Pass Tuff are distinguished by the sizes and amounts of their pumice and lithic clasts and their degree of welding. Pyroclastic units of the Prow Pass Tuff are distinguished from those of the Calico Hills Formation by their phenocryst assemblage, chemical composition, and ubiquitous siltstone lithic clasts. Downhole resistivity tends to mirror the content of authigenic minerals, primarily zeolites, in both for-mations and may be useful for recognizing the vitric-zeolite boundary in the study area. Maps of zeolite distribution illustrate that the bedded tuff and basal sandstone units of the Calico Hills Formation are altered over a wider area than the pyroclastic units of both the Calico Hills Formation and the upper Prow Pass Tuff.

  17. Presence of the dinosaur Scelidosaurus indicates Jurassic age for the Kayenta Formation (Glen Canyon Group, northern Arizona)

    Science.gov (United States)

    Padian, Kevin

    1989-05-01

    The Glen Canyon Group (Moenave, Wingate, Kayenta and Navajo Formations) of northern Arizona represents an extensive outcrop of early Mesozoic age terrestrial sediments. The age of these formations has long been disputed because independent stratigraphic data from marine tie-ins, paleobotanical and palynological evidence, and radiometric calibrations have been scanty or absent. The fauna of the Kayenta Formation in particular has been problematic because it has appeared to contain both typical Late Triassic and Early Jurassic taxa Here I report that the principal evidence for Late Triassic taxa, dermal scutes previously assigned to an aetosaur, in fact belongs to the thyreophoran ornithischian dinosaur Scelidosaurus, previously known only as a washed-in form found in marine sediments in the Early Jurassic of England. The presence of this dinosaur represents the first vertebrate biostratigraphic tie-in of the Glen Canyon Group horizons with reliably dated marine deposits in Europe. Together with revised systematic assessments of other vertebrates and independent evidence from fossil pollen, it supports an Early Jurassic age for the Kayenta Formation and most or all of the Glen Canyon Group.

  18. Comparative analysis of the calcretization process in the Marilia formations (Bauru group - Brasil) and Mercedes ( Paysandu group - Uruguay), Upper Cretaceous of the Parana basin

    International Nuclear Information System (INIS)

    Veroslavsky, G.; Etchebehere, M.; Sad, A.; Fulfaro, J.

    1998-01-01

    Pedogenic and non-pedogenic calcrete facies are very common feature of Marilia (Brazil) and Mercedes (Uruguay) formations in the Parana Basin. The non-pedogenic ones constitute massive limestone facies that have been recently interpreted as groundwater calcretes. These limestones are exploited in both countries to supply raw materials to Portland cement and soil conditioner in origin and age of calcretization phenomena. In Uruguay, the calcretization process seens to be band formation. Field relationships and fossil assemblage point to a Paleocene (or later) age for the calcretization. In Brazilian territory, the groundwater calcretes aresupposed to be of Upper Cretaceous age due to the presence of dinosaurs scattered through the Bauru Group, including siliciclastic beds below and above the calcretes. The authors assume that calcretization processes are similar in both countries (host rocks, intensity, size, textures, geometries and economic potential). The main difference is in age of the calcretization. (author)

  19. Educational Outcomes of Small-Group Discussion Versus Traditional Lecture Format in Dental Students' Learning and Skills Acquisition.

    Science.gov (United States)

    Arias, Ana; Scott, Raymond; Peters, Ove A; McClain, Elizabeth; Gluskin, Alan H

    2016-04-01

    The aim of this prospective quantitative study was to compare the effect of different instructional formats on dental students' skills and knowledge acquisition for access cavity preparation. All first-year dental students were invited to participate in this study conducted during the four consecutive two-week endodontic rotation courses at the University of the Pacific Arthur A. Dugoni School of Dentistry in spring semester 2015. Four alphabetically distributed intact groups of students were randomly allocated to two groups (n=70 each) that participated in either small-group discussion or a traditional lecture on access preparation. The first outcome measure was skill acquisition, measured by the quality of access cavities prepared in extracted teeth at the conclusion of the session. Two blinded raters scored direct observations on a continuous scale. Knowledge, the second outcome measure, was scored with a multiple-choice and open-ended question test at the end of each two-week session. Data were obtained for 134 of the 140 students, for a 96% response rate. The results showed that students in the small-group discussion groups scored significantly higher than those in the lecture groups when skill performance was tested (p=8.9 × 10(-7)). However, no significant differences were found in the acquisition of knowledge between the two groups on the written test. Active student participation was significantly related to improved manual skill acquisition, but the format of the session does not seem to have had a direct influence on acquired knowledge.

  20. Depositional History and Sequence Stratigraphy of the Middle Ordovician Yeongheung Formation (Yeongweol Group), Taebaeksan Basin, mid-east Korea

    Science.gov (United States)

    Kwon, Yoo Jin; Kwon, Yi Kyun

    2017-04-01

    The Middle Ordovician Yeongheung Formation consists of numerous meter-scale, shallowing-upward cycles which were deposited on a shallow-marine carbonate platform. Many diagnostic sedimentary textures and structures such as supratidal laminite, tepee structure, and solution-collapsed breccia are observed, which enable to infer the dry climate and high salinity conditions during deposition of the formation. In order to understand its depositional history, this study focuses on vertical and spatial stacking patterns of the second- to third-order sequences through the detailed outcrop description and geologic mapping. A total 19 lithofacies have been recognized, which can be grouped into 5 facies associations (FAs): FA1 (Supratidal flat), FA2 (Supratidal or dolomitization of peritidal facies), FA3 (Intertidal flat), FA4 (Shallow subtidal to peritidal platform), FA5 (Shallow subtidal shoal). Global mega-sequence boundary (Sauk-Tippecanoe) occurs in solution-collapsed breccia zone in the lower part of the formation. Correlation of the shallowing-upward cycle stacking pattern across the study area defines 6 transgressive-regressive depositional sequences. Each depositional sequences comprises a package of vertical and spatial staking of shallow subtidal cycles in the lower part and peritidal cycles in the upper part of the formation. According to sequence stratigraphic interpretation, the reconstructed relative sea-level curve of the Yeongweol platform is very similar to that of the Taebaek platform. Based on the absence of siliciclastic sequence such as the Jigunsan Formation and the lithologic & stratigraphic differences, however, the Yeongweol and Taebaek groups might not belong to a single depositional system within the North China platform. The Yeongweol Group can be divided by the four subunits into their unique lithologic successions and geographic distributions. The Eastern subunit of the Yeongweol Group is composed dominantly of carbonate rocks with a high

  1. Item Construction Using Reflective, Formative, or Rasch Measurement Models: Implications for Group Work

    Science.gov (United States)

    Peterson, Christina Hamme; Gischlar, Karen L.; Peterson, N. Andrew

    2017-01-01

    Measures that accurately capture the phenomenon are critical to research and practice in group work. The vast majority of group-related measures were developed using the reflective measurement model rooted in classical test theory (CTT). Depending on the construct definition and the measure's purpose, the reflective model may not always be the…

  2. A Possible Link Between Winter Arctic Sea Ice Decline and a Collapse of the Beaufort High?

    Science.gov (United States)

    Petty, Alek A.

    2018-03-01

    A new study by Moore et al. (2018, https://doi.org/10.1002/2017GL076446) highlights a collapse of the anticyclonic "Beaufort High" atmospheric circulation over the western Arctic Ocean in the winter of 2017 and an associated reversal of the sea ice drift through the southern Beaufort Sea (eastward instead of the predominantly westward circulation). The authors linked this to the loss of sea ice in the Barents Sea, anomalous warming over the region, and the intrusion of low-pressure cyclones along the eastern Arctic. In this commentary we discuss the significance of this observation, the challenges associated with understanding these possible linkages, and some of the alternative hypotheses surrounding the impacts of winter Arctic sea ice loss.

  3. Impact of environmental factors on the distribution of extreme scouring (gouging) event, Canadian Beaufort shelf

    Energy Technology Data Exchange (ETDEWEB)

    Blasco, Steve [Geological Survey of Canada, Dartmouth (Canada); Carr, Erin; Campbell, Patrick [Canadian Seabed Research Ltd., Porters Lake (Canada); Shearer, Jim [Shearer Consulting, Ottawa (Canada)

    2011-07-01

    A knowledge of the presence of scours, their dimensions and their return frequencies is highly important in the development of hydrocarbon offshore structures. Mapping surveys have identified 290 extreme scour events across the Canadian Beaufort shelf. This paper investigated the impact of environmental factors on the distribution of extreme scouring events in the Canadian Beaufort shelf. This study used the NEWBASE database of new ice scours to perform an analysis of the scours appearance mechanisms. The geotechnical zonation, the bathymetry and the shelf gradient were evaluated using these data. Estimation of the surficial sediment type, the surficial sediment thickness and sea ice regime were also made. It was found that the spatial distribution of extreme scour events is controlled by sea-ice regime, bathymetry and geotechnical zonation. The results obtained from mapping surveys suggested that the key controlling environmental factors may combine to limit the depth of extreme scour events to 5 meters.

  4. Undergraduate ALFALFA Team: Analysis of Spatially-Resolved Star-Formation in Nearby Galaxy Groups and Clusters

    Science.gov (United States)

    Finn, Rose; Collova, Natasha; Spicer, Sandy; Whalen, Kelly; Koopmann, Rebecca A.; Durbala, Adriana; Haynes, Martha P.; Undergraduate ALFALFA Team

    2017-01-01

    As part of the Undergraduate ALFALFA Team, we are conducting a survey of the gas and star-formation properties of galaxies in 36 groups and clusters in the local universe. The galaxies in our sample span a large range of galactic environments, from the centers of galaxy groups and clusters to the surrounding infall regions. One goal of the project is to map the spatial distribution of star-formation; the relative extent of the star-forming and stellar disks provides important information about the internal and external processes that deplete gas and thus drive galaxy evolution. We obtained wide-field H-alpha observations with the WIYN 0.9m telescope at Kitt Peak National Observatory for galaxies in the vicinity of the MKW11 and NRGb004 galaxy groups and the Abell 1367 cluster. We present a preliminary analysis of the relative size of the star-forming and stellar disks as a function of galaxy morphology and local galaxy density, and we calculate gas depletion times using star-formation rates and HI gas mass. We will combine these results with those from other UAT members to determine if and how environmentally-driven gas depletion varies with the mass and X-ray properties of the host group or cluster. This work has supported by NSF grants AST-0847430, AST-1211005 and AST-1637339.

  5. The delivery of mercury to the Beaufort Sea of the Arctic Ocean by the Mackenzie River.

    Science.gov (United States)

    Leitch, Daniel R; Carrie, Jesse; Lean, David; Macdonald, Robie W; Stern, Gary A; Wang, Feiyue

    2007-02-01

    Very high levels of mercury (Hg) have recently been reported in marine mammals and other higher trophic-level biota in the Mackenzie Delta and Beaufort Sea of the western Arctic Ocean. To quantify the input of Hg (particulate, dissolved and methylated) by the Mackenzie River as a potential source for Hg in the ecosystem, surface water and sediment samples were taken from 79 sites in the lower Mackenzie Basin during three consecutive summers (2003-2005) and analyzed for Hg and methylmercury (MeHg). Intensive studies were also carried out in the Mackenzie Delta during the freshets of 2004 and 2005. Large seasonal and annual variations were found in Hg concentrations in the river, coincident with the variations in water discharge. Increased discharges during spring freshet and during the summers of 2003 and 2005 compared to 2004 were mirrored by higher Hg concentrations. The correlation between Hg concentration and riverflow suggests additional Hg sources during periods of high water, potentially from increased surface inundation and increased bank erosion. The increase in the Hg concentration with increasing water discharge amplifies the annual Hg and MeHg fluxes during high water level years. For the period 2003-2005, the Hg and MeHg fluxes from the Mackenzie River to the Beaufort Sea averaged 2.2 tonnes/yr and 15 kg/yr, respectively, the largest known Hg source to the Beaufort Sea. More than half of the mercury flux occurs during the short spring freshet season which coincides with the period of rapid growth of marine biota. Consequently, the Mackenzie River input potentially provides the major mercury source to marine mammals of the Beaufort Sea. The Hg and MeHg fluxes from the Mackenzie River are expected to further increase with the projected climate warming in the Mackenzie Basin.

  6. Group formation in a public good experiment: on the dynamics of social ties structures

    NARCIS (Netherlands)

    Sonnemans, J.H.; van Dijk, F.; van Winden, F.A.A.M.

    1999-01-01

    Economic behavior often takes place in groups of small numbers of peopleinteracting with each other (like work teams, neighborhoods, socialnetworks, etc.). Characteristic of such interaction is the development of(affective) interpersonal relationships, or social ties. According tosociologists, the

  7. Recent observations of intraspecific predation and cannibalism among polar bears in the southern Beaufort Sea

    Science.gov (United States)

    Amstrup, Steven C.; Stirling, I.; Smith, T.S.; Perham, C.; Thiemann, G.W.

    2006-01-01

    Intraspecific killing has been reported among polar bears (Ursus maritimus), brown bears (U. arctos), and black bears (U. americanus). Although cannibalism is one motivation for such killings, the ecological factors mediating such events are poorly understood. Between 24 January and 10 April 2004, we confirmed three instances of intraspecific predation and cannibalism in the Beaufort Sea. One of these, the first of this type ever reported for polar bears, was a parturient female killed at her maternal den. The predating bear was hunting in a known maternal denning area and apparently discovered the den by scent. A second predation event involved an adult female and cub recently emerged from their den, and the third involved a yearling male. During 24 years of research on polar bears in the southern Beaufort Sea region of northern Alaska and 34 years in northwestern Canada, we have not seen other incidents of polar bears stalking, killing, and eating other polar bears. We hypothesize that nutritional stresses related to the longer ice-free seasons that have occurred in the Beaufort Sea in recent years may have led to the cannibalism incidents we observed in 2004. ?? Springer-Verlag 2006.

  8. Petrology and geochemistry of REE-rich Mafé banded iron formations (Bafia group, Cameroon)

    Science.gov (United States)

    Nkoumbou, Charles; Gentry, Fuh Calistus; Tchakounte Numbem, Jacqueline; Belle Ekwe Lobé, Yolande Vanessa; Nwagoum Keyamfé, Christin Steve

    2017-07-01

    Archaean-Paleoproterozoic foliated amphibole-gneisses and migmatites interstratified with amphibolites, pyroxeno-amphibolites and REE-rich banded-iron formations outcrop at Mafé, Ndikinimeki area. The foliation is nearly vertical due to tight folds. Flat-lying quartz-rich mica schists and quartzites, likely of Pan-African age, partly cover the formations. Among the Mafé BIFs, the oxide BIF facies shows white layers of quartz and black layers of magnetite and accessory hematite, whereas the silicate BIF facies is made up of thin discontinuous quartz layers alternating with larger garnet (almandine-spessartine) + chamosite + ilmenite ± Fe-talc layers. REE-rich oxide BIFs compositions are close to the East Pacific Rise (EPR) hydrothermal deposit; silicate BIFs plot midway between EPR and the associated amphibolite, accounting for a contamination by volcanic materials, in addition to the hydrothermal influence during their oceanic deposition. The association of an oceanic setting with alkaline and tholeiitic magmatism is typical of the Algoma-type BIF deposit. The REE-rich BIFs indices recorded at Mafé are interpreted as resulting from an Archaean-Paleoproterozoic mineralization.

  9. Use of formative research and social network theory to develop a group walking intervention: Sumter County on the Move!

    Science.gov (United States)

    Forthofer, Melinda; Burroughs-Girardi, Ericka; Stoisor-Olsson, Liliana; Wilcox, Sara; Sharpe, Patricia A; Pekuri, Linda M

    2016-10-01

    Although social support is a frequently cited enabler of physical activity, few studies have examined how to harness social support in interventions. This paper describes community-based formative research to design a walking program for mobilizing naturally occurring social networks to support increases in walking behavior. Focus group methods were used to engage community members in discussions about desired walking program features. The research was conducted with underserved communities in Sumter County, South Carolina. The majority of focus group participants were women (76%) and African American (92%). Several important themes emerged from the focus group results regarding attitudes toward walking, facilitators of and barriers to walking, ideal walking program characteristics, and strategies for encouraging community members to walk. Most noteably, the role of existing social networks as a supportive influence on physical activity was a recurring theme in our formative research and a gap in the existing evidence base. The resulting walking program focused on strategies for mobilizing, supporting and reinforcing existing social networks as mechanisms for increasing walking. Our approach to linking theory, empirical evidence and community-based formative research for the development of a walking intervention offers an example for practitioners developing intervention strategies for a wide range of behaviors. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. The International Dermatology Outcome Measures Group: formation of patient-centered outcome measures in dermatology.

    Science.gov (United States)

    Gottlieb, Alice B; Levin, Adriane A; Armstrong, April W; Abernethy, April; Duffin, Kristina Callis; Bhushan, Reva; Garg, Amit; Merola, Joseph F; Maccarone, Mara; Christensen, Robin

    2015-02-01

    As quality standards are increasingly in demand throughout medicine, dermatology needs to establish outcome measures to quantify the effectiveness of treatments and providers. The International Dermatology Outcome Measures Group was established to address this need. Beginning with psoriasis, the group aims to create a tool considerate of patients and providers using the input of all relevant stakeholders in assessment of disease severity and response to treatment. Herein, we delineate the procedures through which consensus is being reached and the future directions of the project. Copyright © 2014 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

  11. ON THE FORMATION OF AMIDE POLYMERS VIA CARBONYL–AMINO GROUP LINKAGES IN ENERGETICALLY PROCESSED ICES OF ASTROPHYSICAL RELEVANCE

    Energy Technology Data Exchange (ETDEWEB)

    Förstel, Marko; Maksyutenko, Pavlo; Jones, Brant M.; Kaiser, Ralf I. [Department of Chemistry, University of Hawaii, 2545 McCarthy Mall, 96822 HI (United States); Sun, Bing J.; Lee, Huan C.; Chang, Agnes H. H., E-mail: ralfk@hawaii.edu, E-mail: hhchang@mail.ndhu.edu.tw [Department of Chemistry, National Dong Hwa University, Shoufeng, Hualien 974, Taiwan (China)

    2016-04-01

    We report on the formation of organic amide polymers via carbonyl–amino group linkages in carbon monoxide and ammonia bearing energetically processed ices of astrophysical relevance. The first group comprises molecules with one carboxyl group and an increasing number of amine moieties starting with formamide (45 u), urea (60 u), and hydrazine carboxamide (75 u). The second group consists of species with two carboxyl (58 u) and up to three amine groups (73 u, 88 u, and 103 u). The formation and polymerization of these linkages from simple inorganic molecules via formamide und urea toward amide polymers is discussed in an astrophysical and astrobiological context. Our results show that long chain molecules, which are closely related to polypeptides, easily form by energetically processing simple, inorganic ices at very low temperatures and can be released into the gas phase by sublimation of the ices in star-forming regions. Our experimental results were obtained by employing reflectron time-of-flight mass spectroscopy, coupled with soft, single photon vacuum ultraviolet photoionization; they are complemented by theoretical calculations.

  12. ON THE FORMATION OF AMIDE POLYMERS VIA CARBONYL–AMINO GROUP LINKAGES IN ENERGETICALLY PROCESSED ICES OF ASTROPHYSICAL RELEVANCE

    International Nuclear Information System (INIS)

    Förstel, Marko; Maksyutenko, Pavlo; Jones, Brant M.; Kaiser, Ralf I.; Sun, Bing J.; Lee, Huan C.; Chang, Agnes H. H.

    2016-01-01

    We report on the formation of organic amide polymers via carbonyl–amino group linkages in carbon monoxide and ammonia bearing energetically processed ices of astrophysical relevance. The first group comprises molecules with one carboxyl group and an increasing number of amine moieties starting with formamide (45 u), urea (60 u), and hydrazine carboxamide (75 u). The second group consists of species with two carboxyl (58 u) and up to three amine groups (73 u, 88 u, and 103 u). The formation and polymerization of these linkages from simple inorganic molecules via formamide und urea toward amide polymers is discussed in an astrophysical and astrobiological context. Our results show that long chain molecules, which are closely related to polypeptides, easily form by energetically processing simple, inorganic ices at very low temperatures and can be released into the gas phase by sublimation of the ices in star-forming regions. Our experimental results were obtained by employing reflectron time-of-flight mass spectroscopy, coupled with soft, single photon vacuum ultraviolet photoionization; they are complemented by theoretical calculations

  13. Features of the formative educational training groups in Youth sports schools in terms of our time

    Directory of Open Access Journals (Sweden)

    Artem Zhytnitskyi

    2015-12-01

    Full Text Available Purpose: identify the factors affecting the effective performance of the Children and Youth Sports School at the initial and preliminary stage of basic training. Material and Methods: analysis of the literary base, pedagogical research methods, statistical methods, questionnaire. Results: the understanding of the factors influencing the motor skills formation of students is displayed. The author grounded three-dimensional understanding of dissimilar conditions and factors determining the functionality of a Children and Youth Sports School taking into account the motivation of students the scope of use of the skills and other factors which don’t deal with teaching science. Conclusions: it was found that miscellaneous factors, many of which are associated with the state of material and technical base and infrastructure of the school, the region and the country as a whole affect screening the contingent of a Children and Youth Sports School

  14. Dietary treatment of urinary risk factors for renal stone formation. A review of CLU Working Group.

    Science.gov (United States)

    Prezioso, Domenico; Strazzullo, Pasquale; Lotti, Tullio; Bianchi, Giampaolo; Borghi, Loris; Caione, Paolo; Carini, Marco; Caudarella, Renata; Ferraro, Manuel; Gambaro, Giovanni; Gelosa, Marco; Guttilla, Andrea; Illiano, Ester; Martino, Marangella; Meschi, Tiziana; Messa, Piergiorgio; Miano, Roberto; Napodano, Giorgio; Nouvenne, Antonio; Rendina, Domenico; Rocco, Francesco; Rosa, Marco; Sanseverino, Roberto; Salerno, Annamaria; Spatafora, Sebastiano; Tasca, Andrea; Ticinesi, Andrea; Travaglini, Fabrizio; Trinchieri, Alberto; Vespasiani, Giuseppe; Zattoni, Filiberto

    2015-07-07

    Diet interventions may reduce the risk of urinary stone formation and its recurrence, but there is no conclusive consensus in the literature regarding the effectiveness of dietary interventions and recommendations about specific diets for patients with urinary calculi. The aim of this study was to review the studies reporting the effects of different dietary interventions for the modification of urinary risk factors in patients with urinary stone disease. A systematic search of the Pubmed database literature up to July 1, 2014 for studies on dietary treatment of urinary risk factors for urinary stone formation was conducted according to a methodology developed a priori. Studies were screened by titles and abstracts for eligibility. Data were extracted using a standardized form and the quality of evidence was assessed. Evidence from the selected studies were used to form evidence-based guideline statements. In the absence of sufficient evidence, additional statements were developed as expert opinions. General measures: Each patient with nephrolithiasis should undertake appropriate evaluation according to the knowledge of the calculus composition. Regardless of the underlying cause of the stone disease, a mainstay of conservative management is the forced increase in fluid intake to achieve a daily urine output of 2 liters. HYPERCALCIURIA: Dietary calcium restriction is not recommended for stone formers with nephrolithiasis. Diets with a calcium content ≥ 1 g/day (and low protein-low sodium) could be protective against the risk of stone formation in hypercalciuric stone forming adults. Moderate dietary salt restriction is useful in limiting urinary calcium excretion and thus may be helpful for primary and secondary prevention of nephrolithiasis. A low-normal protein intake decrease calciuria and could be useful in stone prevention and preservation of bone mass. Omega-3 fatty acids and bran of different origin decreases calciuria, but their impact on the urinary

  15. Dietary treatment of urinary risk factors for renal stone formation. A review of CLU Working Group

    Directory of Open Access Journals (Sweden)

    Domenico Prezioso

    2015-07-01

    Full Text Available Objective: Diet interventions may reduce the risk of urinary stone formation and its recurrence, but there is no conclusive consensus in the literature regarding the effectiveness of dietary interventions and recommendations about specific diets for patients with urinary calculi. The aim of this study was to review the studies reporting the effects of different dietary interventions for the modification of urinary risk factors in patients with urinary stone disease. Materials and Methods: A systematic search of the Pubmed database literature up to July 1, 2014 for studies on dietary treatment of urinary risk factors for urinary stone formation was conducted according to a methodology developed a priori. Studies were screened by titles and abstracts for eligibility. Data were extracted using a standardized form and the quality of evidence was assessed. Results: Evidence from the selected studies were used to form evidencebased guideline statements. In the absence of sufficient evidence, additional statements were developed as expert opinions. Conclusions: General measures: Each patient with nephrolithiasis should undertake appropriate evaluation according to the knowledge of the calculus composition. Regardless of the underlying cause of the stone disease, a mainstay of conservative management is the forced increase in fluid intake to achieve a daily urine output of 2 liters. Hypercalciuria: Dietary calcium restriction is not recommended for stone formers with nephrolithiasis. Diets with a calcium content ≥ 1 g/day (and low protein-low sodium could be protective against the risk of stone formation in hypercalciuric stone forming adults. Moderate dietary salt restriction is useful in limiting urinary calcium excretion and thus may be helpful for primary and secondary prevention of nephrolithiasis. A low-normal protein intake decrease calciuria and could be useful in stone prevention and preservation of bone mass. Omega-3 fatty acids and bran of

  16. Oxo-group-14-element bond formation in binuclear uranium(V) pacman complexes

    International Nuclear Information System (INIS)

    Jones, Guy M.; Arnold, Polly L.; Love, Jason B.

    2013-01-01

    Simple and versatile routes to the functionalization of uranyl-derived U"V-oxo groups are presented. The oxo-lithiated, binuclear uranium(V)-oxo complexes [{(py)_3LiOUO}_2(L)] and [{(py)_3LiOUO}(OUOSiMe_3)(L)] were prepared by the direct combination of the uranyl(VI) silylamide ''ate'' complex [Li(py)_2][(OUO)(N'')_3](N''=N(SiMe_3)_2) with the polypyrrolic macrocycle H_4L or the mononuclear uranyl (VI) Pacman complex [UO_2(py)(H_2L)], respectively. These oxo-metalated complexes display distinct U-O single and multiple bonding patterns and an axial/equatorial arrangement of oxo ligands. Their ready availability allows the direct functionalization of the uranyl oxo group leading to the binuclear uranium(V) oxo-stannylated complexes [{(R_3Sn)OUO}_2(L)] (R=nBu, Ph), which represent rare examples of mixed uranium/tin complexes. Also, uranium-oxo-group exchange occurred in reactions with [TiCl(OiPr)_3] to form U-O-C bonds [{(py)_3LiOUO}(OUOiPr)(L)] and [(iPrOUO)_2(L)]. Overall, these represent the first family of uranium(V) complexes that are oxo-functionalised by Group 14 elements. (Copyright copyright 2013 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  17. The connection between galaxy formation and the assembly of stellar halos in the Local Group

    NARCIS (Netherlands)

    Helmi, Amina

    I will review our current understanding of the assembly of stellar halos from a theoretical perspective. I will place particular emphasis on how observations of Local Group galaxies can be used to constrain the assembly history of both their stellar and dark matter halos. Finally I will focus on

  18. Training in Statistical Reasoning Inhibits the Formation of Erroneous Group Stereotypes.

    Science.gov (United States)

    Schaller, Mark; And Others

    1996-01-01

    Tested the hypothesis that training in statistical reasoning inhibits erroneous group stereotypes. In study one, 60 students were assigned to a control or one of two training conditions focused on training in the logic of analysis of covariance. Study two (N=82) replicated study one. Study three (N=44) tested an alternative explanation, providing…

  19. In love and war: altruism, norm formation, and two different types of group selection

    NARCIS (Netherlands)

    van Veelen, C.M.; Hopfensitz, A.

    2007-01-01

    We analyse simulations reported in "The co-evolution of individual behaviors and social institutions" by Bowles et al., 2003 in the Journal of Theoretical Biology 223, 135-147, and begin with distinguishing two types of group selection models. The literature does not provide different names for

  20. Efficacy of formative evaluation using a focus group for a large classroom setting in an accelerated pharmacy program.

    Science.gov (United States)

    Nolette, Shaun; Nguyen, Alyssa; Kogan, David; Oswald, Catherine; Whittaker, Alana; Chakraborty, Arup

    2017-07-01

    Formative evaluation is a process utilized to improve communication between students and faculty. This evaluation method allows the ability to address pertinent issues in a timely manner; however, implementation of formative evaluation can be a challenge, especially in a large classroom setting. Using mediated formative evaluation, the purpose of this study is to determine if a student based focus group is a viable option to improve efficacy of communication between an instructor and students as well as time management in a large classroom setting. Out of 140 total students, six students were selected to form a focus group - one from each of six total sections of the classroom. Each focus group representative was responsible for collecting all the questions from students of their corresponding sections and submitting them to the instructor two to three times a day. Responses from the instructor were either passed back to pertinent students by the focus group representatives or addressed directly with students by the instructor. This study was conducted using a fifteen-question survey after the focus group model was utilized for one month. A printed copy of the survey was distributed in the class by student investigators. Questions were of varying types, including Likert scale, yes/no, and open-ended response. One hundred forty surveys were administered, and 90 complete responses were collected. Surveys showed that 93.3% of students found that use of the focus group made them more likely to ask questions for understanding. The surveys also showed 95.5% of students found utilizing the focus group for questions allowed for better understanding of difficult concepts. General open-ended answer portions of the survey showed that most students found the focus group allowed them to ask questions more easily since they did not feel intimidated by asking in front of the whole class. No correlation was found between demographic characteristics and survey responses. This may

  1. The streptococcal collagen-like protein-1 (Scl1 is a significant determinant for biofilm formation by group a Streptococcus

    Directory of Open Access Journals (Sweden)

    Oliver-Kozup Heaven A

    2011-12-01

    Full Text Available Abstract Background Group A Streptococcus (GAS is a human-specific pathogen responsible for a number of diseases characterized by a wide range of clinical manifestations. During host colonization GAS-cell aggregates or microcolonies are observed in tissues. GAS biofilm, which is an in vitro equivalent of tissue microcolony, has only recently been studied and little is known about the specific surface determinants that aid biofilm formation. In this study, we demonstrate that surface-associated streptococcal collagen-like protein-1 (Scl1 plays an important role in GAS biofilm formation. Results Biofilm formation by M1-, M3-, M28-, and M41-type GAS strains, representing an intraspecies breadth, were analyzed spectrophotometrically following crystal violet staining, and characterized using confocal and field emission scanning electron microscopy. The M41-type strain formed the most robust biofilm under static conditions, followed by M28- and M1-type strains, while the M3-type strains analyzed here did not form biofilm under the same experimental conditions. Differences in architecture and cell-surface morphology were observed in biofilms formed by the M1- and M41-wild-type strains, accompanied by varying amounts of deposited extracellular matrix and differences in cell-to-cell junctions within each biofilm. Importantly, all Scl1-negative mutants examined showed significantly decreased ability to form biofilm in vitro. Furthermore, the Scl1 protein expressed on the surface of a heterologous host, Lactococcus lactis, was sufficient to induce biofilm formation by this organism. Conclusions Overall, this work (i identifies variations in biofilm formation capacity among pathogenically different GAS strains, (ii identifies GAS surface properties that may aid in biofilm stability and, (iii establishes that the Scl1 surface protein is an important determinant of GAS biofilm, which is sufficient to enable biofilm formation in the heterologous host

  2. The cultural formation code of successfulness verticals of the U.S. ethnic groups

    Directory of Open Access Journals (Sweden)

    Liudmyla Petrashko

    2010-11-01

    Full Text Available In the article there are outlined the prospects of global economic development. There was built an evolutional model of theoretical studies of the phenomenon “culture” in the context of universal, system and value approaches. It gives the brief characteristics of the cultural assimilation model “melting crucible”. There have been determined the indicators of the successfulness verticals of the U.S. ethnic groups and made their assessment. By virtue of the author’s method is given the assessment of the comparative significance of the heterogeneous cultural codes of maternal (immigration and hosting environment of the USA, which gave the possibility to determine the factors that ensure the economic success of the American ethnic groups. The results of the research provide reasoning for the change of traditional vector of the cultures’ typology and confirm the existence of the progressive cultural codes.

  3. Formation of potential radiation risk groups to render timely targeted medical care: Lessons of Chernobyl

    International Nuclear Information System (INIS)

    Ivanov, V. K.; Kashcheev, V. V.; Zamulaeva, I. A.; Saenko, A. S.; Orlova, N. V.; Smirnova, S. G.; Korelo, A. M.; Gorsky, A. I.; Maksioutov, M. A.

    2012-01-01

    The paper discusses technology for establishing potential cancer risk groups, based on methods of molecular and radiation epidemiology. Assay of gene mutations at the T-cell receptor (TCR) locus as the method of molecular epidemiology was used for measuring the frequency of TCR-mutations in 320 nuclear workers of the Inst. of Physics and Power Engineering (IPPE). The method of radiation epidemiology was applied to the estimation of attributable risk fraction (ARF) for solid cancers in these groups. The main estimates of radiation risk after the Chernobyl accident are in close agreement with the International Commission on Radiological Protection (ICRP) Publication, 103 models published in 2007. In nuclear workers of the IPPE with ARF ≥ 10%, the increased level of TCR-mutations occurs more often (risk ratio=9.7; 95% CI: 2.9; 32.1). (authors)

  4. Oxo-group-14-element bond formation in binuclear uranium(V) pacman complexes

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Guy M.; Arnold, Polly L.; Love, Jason B. [EaStCHEM School of Chemistry, University of Edinburgh (United Kingdom)

    2013-07-29

    Simple and versatile routes to the functionalization of uranyl-derived U{sup V}-oxo groups are presented. The oxo-lithiated, binuclear uranium(V)-oxo complexes [{(py)_3LiOUO}{sub 2}(L)] and [{(py)_3LiOUO}(OUOSiMe{sub 3})(L)] were prepared by the direct combination of the uranyl(VI) silylamide ''ate'' complex [Li(py){sub 2}][(OUO)(N''){sub 3}](N''=N(SiMe{sub 3}){sub 2}) with the polypyrrolic macrocycle H{sub 4}L or the mononuclear uranyl (VI) Pacman complex [UO{sub 2}(py)(H{sub 2}L)], respectively. These oxo-metalated complexes display distinct U-O single and multiple bonding patterns and an axial/equatorial arrangement of oxo ligands. Their ready availability allows the direct functionalization of the uranyl oxo group leading to the binuclear uranium(V) oxo-stannylated complexes [{(R_3Sn)OUO}{sub 2}(L)] (R=nBu, Ph), which represent rare examples of mixed uranium/tin complexes. Also, uranium-oxo-group exchange occurred in reactions with [TiCl(OiPr){sub 3}] to form U-O-C bonds [{(py)_3LiOUO}(OUOiPr)(L)] and [(iPrOUO){sub 2}(L)]. Overall, these represent the first family of uranium(V) complexes that are oxo-functionalised by Group 14 elements. (Copyright copyright 2013 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  5. Mechanism of the Topotactic Formation of gamma-Zirconium Phosphate Covalently Pillared with Diphosphonate Groups.

    Science.gov (United States)

    Alberti, G.; Giontella, E.; Murcia-Mascarós, S.; Vivani, R.

    1998-09-07

    The topotactic reaction of gamma-ZrPO(4)[O(2)P(OH)(2)].2H(2)O (gamma-ZrP) with benzenediphosphonic acid was examined in water and in acetone-water mixtures. This reaction was found to take place in water only on the external surface of the microcrystals, and pillared compounds were never obtained, even after very long reaction times. On the contrary, covalently pillared compounds were quickly obtained in acetone-water mixtures. The mechanism of the latter topotactic reaction was investigated by determining the rate of the phosphate groups released and the rate of the benzenediphosphonates taken up by gamma-ZrP over a long time (50 days). These data showed that pillared derivatives of gamma-ZrP can be obtained because colloidal dispersions of exfoliated lamellae are formed in acetone-water mixtures. The diphosphonate group acts initially as a monovalent species, replacing only one dihydrogen phosphate group on the surface of the exfoliated gamma-lamellae. The colloidal and partially derivatized lamellae thus formed can interact with each other by forming polylamellar pillared systems. When the number of pillared lamellae exceeds a given value (usually 5-6), flocculation of the colloidal gamma-ZrP takes place. Topotactic reactions between packets of pillared lamellae may also continue in the flocculated system. Therefore, the average number of the pillared lamellae slowly increases over time.

  6. Basic Science of the Fundamentals and Dynamics of Social-Fringe Group Formation and Sustainment

    Science.gov (United States)

    2012-08-01

    USTIFY! G BELIEFS: WHAT MOTIVATES THE TERRORISTS •:• A 1-’ltmdry l.ist of 1\\lotivations: llonor, Trauma, Religion, llumtli:uion, Sugma, Feminism ...Group Grievance and Humiliation: A Tool in AI-Qaeda Propaganda •Jihad in Algeria today is YOUR hope with permission from Allah in redemption from...relational) and Morality ! 54! "Hear, Israel, the decrees and laws I declare in your hearing today . Learn them and be sure to foLlow them. The

  7. Chemically mediated group formation in soil-dwelling larvae and pupae of the beetle Trypoxylus dichotomus

    Science.gov (United States)

    Kojima, Wataru; Ishikawa, Yukio; Takanashi, Takuma

    2014-09-01

    Many insects form groups through interactions among individuals, and these are often mediated by chemical, acoustic, or visual cues and signals. In spite of the diversity of soil-dwelling insects, their aggregation behaviour has not been examined as extensively as that of aboveground species. We investigated the aggregation mechanisms of larvae of the Japanese rhinoceros beetle Trypoxylus dichotomus, which live in groups in humus soil. In two-choice laboratory tests, 2nd- and 3rd-instar larvae gathered at conspecific larvae irrespective of the kinship. The ablation of maxillae, which bear chemosensilla, abolished aggregation behaviour. Intact larvae also exhibited aggregation behaviour towards a larval homogenate. These results suggest that larval aggregation is mediated by chemical cues. We also demonstrated that the mature larvae of T. dichotomus built their pupal cells close to a mesh bag containing a conspecific pupal cell, which indicated that larvae utilize chemical cues emanating from these cells to select the pupation site. Thus, the larvae of T. dichotomus may use chemical cues from the conspecifics in two different contexts, i.e. larval aggregation and pupation site selection. Using conspecific cues, larvae may be able to choose suitable locations for foraging or building pupal cells. The results of the present study highlight the importance of chemical information in belowground ecology.

  8. Formation of Silver Nanoplates Layer on Amino Group Grafted Silica Coatings

    Directory of Open Access Journals (Sweden)

    Jurgis PILIPAVICIUS

    2016-05-01

    Full Text Available In this study the self-arrangement of Ag nanoplates on (3-Aminopropyltriethoxysilane (APTES silanized silica coatings was investigated. Silica coatings were made by sol-gel method and silanized in two different ways. The first one includes silanization in acidic 2-propanol solution, the other one – in dry toluene. Coatings were silanized by using different amounts of APTES in case of silanization in 2-propanol. Silver nanoplates layer of functionalized silica coatings was obtained via self-assembly. Coatings were investigated by atomic force microscopy (AFM, water contact angle measurements (CA, FT-IR analysis, and scanning electron microscopy (SEM. Research showed that dense Ag nanoplates arrangement occurs when there is a high amount of amino groups on the surface.DOI: http://dx.doi.org/10.5755/j01.ms.22.2.8405

  9. In love and war: altruism, norm formation, and two different types of group selection.

    Science.gov (United States)

    van Veelen, Matthijs; Hopfensitz, Astrid

    2007-12-21

    We analyse simulations reported in "The co-evolution of individual behaviors and social institutions" by Bowles et al., 2003 in the Journal of Theoretical Biology 223, 135-147, and begin with distinguishing two types of group selection models. The literature does not provide different names for them, but they are shown to be fundamentally different and have quite different empirical implications. The working of the first one depends on the answer to the question "is the probability that you also are an altruist large enough", while the other needs an affirmative answer to "are our interests enough in line". The first one therefore can also be understood as a kin selection model, while the working of the second can also be described in terms of the direct benefits. The actual simulation model is a combination of the two. It is also a Markov chain, which has important implications for how the output data should be handled.

  10. S-Lagrangian dynamics of many-body systems and behavior of social groups: Dominance and hierarchy formation

    Science.gov (United States)

    Sandler, U.

    2017-11-01

    In this paper, we extend our generalized Lagrangian dynamics (i.e., S-Lagrangian dynamics, which can be applied equally to physical and non-physical systems as per Sandler (2014)) to many-body systems. Unlike common Lagrangian dynamics, this is not a trivial task. For many-body systems with S-dependent Lagrangians, the Lagrangian and the corresponding Hamiltonian or energy become vector functions, conjugated momenta become second-order tensors, and the system inevitably develops a hierarchical structure, even if all bodies initially have similar status and Lagrangians. As an application of our theory, we consider dominance and hierarchy formation, which is present in almost all communities of living species. As a biological basis for this application, we assume that the primary motivation of a groups activity is to attempt to cope with stress arising as pressure from the environment and from intrinsic unmet needs of individuals. It has been shown that the S-Lagrangian approach to a group's evolution naturally leads to formation of linear or despotic dominance hierarchies, depending on differences between individuals in coping with stress. That is, individuals that cope more readily with stress take leadership roles during the evolution. Experimental results in animal groups which support our assumption and findings are considered.

  11. Revisiting the merits of a mandatory large group classroom learning format: an MD-MBA perspective.

    Science.gov (United States)

    Li, Shawn X; Pinto-Powell, Roshini

    2017-01-01

    The role of classroom learning in medical education is rapidly changing. To promote active learning and reduce student stress, medical schools have adopted policies such as pass/fail curriculums and recorded lectures. These policies along with the rising importance of the USMLE (United States Medical Licensing Examination) exams have made asynchronous learning popular to the detriment of classroom learning. In contrast to this model, modern day business schools employ mandatory large group classes with assigned seating and cold-calling. Despite similar student demographics, medical and business schools have adopted vastly different approaches to the classroom. When examining the classroom dynamic at business schools with mandatory classes, it is evident that there's an abundance of engaging discourse and peer learning objectives that medical schools share. Mandatory classes leverage the network effect just like social media forums such as Facebook and Twitter. That is, the value of a classroom discussion increases when more students are present to participate. At a time when students are savvy consumers of knowledge, the classroom is competing against an explosion of study aids dedicated to USMLE preparation. Certainly, the purpose of medical school is not solely about the efficient transfer of knowledge - but to train authentic, competent, and complete physicians. To accomplish this, we must promote the inimitable and deeply personal interactions amongst faculty and students. When viewed through this lens, mandatory classes might just be a way for medical schools to leverage their competitive advantage in educating the complete physician.

  12. Group A Streptococcus Prevents Mast Cell Degranulation to Promote Extracellular Trap Formation

    Directory of Open Access Journals (Sweden)

    Mary Clark

    2018-02-01

    Full Text Available The resurgence of Group A Streptococcus (GAS infections in the past two decades has been a rising major public health concern. Due to a large number of GAS infections occurring in the skin, mast cells (MCs, innate immune cells known to localize to the dermis, could play an important role in controlling infection. MCs can exert their antimicrobial activities either early during infection, by degranulation and release of antimicrobial proteases and the cathelicidin-derived antimicrobial peptide LL-37, or by forming antibacterial MC extracellular traps (MCETs in later stages of infection. We demonstrate that MCs do not directly degranulate in response to GAS, reducing their ability to control bacterial growth in early stages of infection. However, MC granule components are highly cytotoxic to GAS due to the pore-forming activity of LL-37, while MC granule proteases do not significantly affect GAS viability. We therefore confirmed the importance of MCETs by demonstrating their capacity to reduce GAS survival. The data therefore suggests that LL-37 from MC granules become embedded in MCETs, and are the primary effector molecule by which MCs control GAS infection. Our work underscores the importance of a non-traditional immune effector cell, utilizing a non-conventional mechanism, in the defense against an important human pathogen.

  13. Refining the chronostratigraphy of the Karoo Basin, South Africa: magnetostratigraphic constraints support an early Permian age for the Ecca Group

    Science.gov (United States)

    Belica, Mercedes E.; Tohver, Eric; Poyatos-Moré, Miquel; Flint, Stephen; Parra-Avila, Luis A.; Lanci, Luca; Denyszyn, Steven; Pisarevsky, Sergei A.

    2017-12-01

    The Beaufort Group of the Karoo Basin, South Africa provides an important chrono- and biostratigraphic record of vertebrate turnovers that have been attributed to the end-Permian mass extinction events at ca. 252 and 260 Ma. However, an unresolved controversy exists over the age of the Beaufort Group due to a large data set of published U-Pb SHRIMP (Sensitive High Resolution Ion Microprobe) zircon results that indicate a ca. 274-250 Ma age range for deposition of the underlying Ecca Group. This age range requires the application of a highly diachronous sedimentation model to the Karoo Basin stratigraphy and is not supported by published palaeontologic and palynologic data. This study tested the strength of these U-Pb isotopic data sets using a magnetostratigraphic approach. Here, we present a composite ∼1500 m section through a large part of the Ecca Group from the Tanqua depocentre, located in the southwestern segment of the Karoo Basin. After the removal of two normal polarity overprints, a likely primary magnetic signal was isolated at temperatures above 450 °C. This section is restricted to a reverse polarity, indicating that it formed during the Kiaman Reverse Superchron (ca. 318-265 Ma), a distinctive magnetostratigraphic marker for early-middle Permian rocks. The Ecca Group has a corresponding palaeomagnetic pole at 40.8°S, 77.4°E (A95 = 5.5°). U-Pb SHRIMP ages on zircons are presented here for comparison with prior isotopic studies of the Ecca Group. A weighted mean U-Pb age of 269.5 ± 1.2 Ma was determined from a volcanic ash bed located in the uppermost Tierberg Formation sampled from the O + R1 research core. The age is interpreted here as a minimum constraint due to a proposed Pb-loss event that has likely influenced a number of published results. A comparison with the Geomagnetic Polarity Time Scale as well as published U-Pb TIMS ages from the overlying Beaufort Group supports a ca. 290-265 Ma age for deposition of the Ecca Group.

  14. Archean Age Fossils from Northwestern Australia (Approximately 3.3 to 3.5 GA, Warrawoona Group, Towers Formation)

    Science.gov (United States)

    Smith, Penny A. Morris

    1999-01-01

    Archean aged rocks from the Pilbara Block area of western Australia (Warrawoona Group, Towers Formation, -3.3-3.5 Ga) contain microfossils that are composed of various sizes of spheres and filaments. The first descriptions of these microfossils were published in the late 1970's (Dunlop, 1978; Dunlop, et. al., 1978). The authenticity of the microfossils is well established. The small size of the microfossils prevents isotope dating, at least with the present technology. Microbiologists, however, have established guidelines to determine the authenticity of the Archean aged organic remains (Schopf, Walter, 1992).

  15. Geochemistry and geochronology of the Archean and palaeo-Proterozoic formations of southern Cameroon (Ntem group, Congo craton)

    International Nuclear Information System (INIS)

    Rchameni, R.

    1997-01-01

    The aim of this work is to understand the crustal evolution of the NW margin of the Congo craton using structural, petrography, isotopic, geochemical and geochronological studies of the Archean and palaeo-Proterozoic formations of the Ntem group of southern Cameroon. The synthesis of these studies allows to propose a diapir-type gravity model linked with the genesis of granitoids to explain the geodynamical evolution of this part of the craton during the Archean. A convergence model with the collision of the Congo and Sao-Francisco cratons and with crust thickening followed by a relaxation phase is proposed for the palaeo-Proterozoic. (J.S.)

  16. Distal alluvial fan sediments in early Proterozoic red beds of the Wilgerivier formation, Waterberg Group, South Africa

    Science.gov (United States)

    Van Der Neut, M.; Eriksson, P. G.; Callaghan, C. C.

    The 1900 - 1700 M.a. Waterberg Group belongs to a series of southern African cratonic cover sequences of roughly equivalent age. Red beds of the Wilgerivier Formation comprise sandstones, interbedded with subordinate conglomerates and minor mudrocks. These immature sedimentary rocks exhibit lenticular bedding, radial palaeocurrent patterns and features indicative of both streamflow and gravity-flow deposition. A distal wet alluvial fan palaeoenvironmental setting is envisaged, with fan-deltas forming where alluvial lobes prograded into a lacustrine basin. Intrastratal, diagenetic alteration of ferromagnesian detrital grains and ferruginous grain coatings led to the red colouration of the Wilgerivier sediments.

  17. The Pan-STARRS1 Medium-deep Survey: Star Formation Quenching in Group and Cluster Environments

    Energy Technology Data Exchange (ETDEWEB)

    Jian, Hung-Yu; Lin, Lihwai; Lin, Kai-Yang; Chen, Chin-Wei [Institute of Astronomy and Astrophysics, Academia Sinica, 106, Taipei, Taiwan, R.O.C. (China); Foucaud, Sebastien [Department of Earth Sciences, National Taiwan Normal University, N.88, Tingzhou Road, Sec. 4, Taipei 11677, Taiwan, R.O.C. (China); Chiueh, Tzihong [Department of Physics, National Taiwan University, 106, Taipei, Taiwan, R.O.C. (China); Bower, R. G.; Cole, Shaun; Draper, P. W.; Metcalfe, N. [Institute for Computational Cosmology, Department of Physics, Durham University, South Road, Durham DH1 3LE (United Kingdom); Chen, Wen-Ping [Graduate Institute of Astronomy, National Central University, Chung-Li 32054, Taiwan, R.O.C. (China); Burgett, W. S.; Flewelling, H.; Huber, M. E.; Kaiser, N.; Kudritzki, R.-P.; Magnier, E. A.; Wainscoat, R. J.; Waters, C., E-mail: hyjian@asiaa.sinica.edu.tw [Institute for Astronomy, University of Hawaii at Manoa, Honolulu, HI 96822 (United States)

    2017-08-10

    We make use of a catalog of 1600 Pan-STARRS1 groups produced by the probability friends-of-friends algorithm to explore how the galaxy properties, i.e., the specific star formation rate (SSFR) and quiescent fraction, depend on stellar mass and group-centric radius. The work is the extension of Lin et al. In this work, powered by a stacking technique plus a background subtraction for contamination removal, a finer correction and more precise results are obtained than in our previous work. We find that while the quiescent fraction increases with decreasing group-centric radius, the median SSFRs of star-forming galaxies in groups at fixed stellar mass drop slightly from the field toward the group center. This suggests that the main quenching process in groups is likely a fast mechanism. On the other hand, a reduction in SSFRs by ∼0.2 dex is seen inside clusters as opposed to the field galaxies. If the reduction is attributed to the slow quenching effect, the slow quenching process acts dominantly in clusters. In addition, we also examine the density–color relation, where the density is defined by using a sixth-nearest-neighbor approach. Comparing the quiescent fractions contributed from the density and radial effect, we find that the density effect dominates the massive group or cluster galaxies, and the radial effect becomes more effective in less massive galaxies. The results support mergers and/or starvation as the main quenching mechanisms in the group environment, while harassment and/or starvation dominate in clusters.

  18. Migros-3: a code for the generation of group constants for reactor calculations from neutron nuclear data in KEDAK format

    International Nuclear Information System (INIS)

    Broeders, I.; Krieg, B.

    1977-01-01

    The code MIGROS-3 was developed from MIGROS-2. The main advantage of MIGROS-3 is its compatibility with the new conventions of the latest version of the Karlsruhe nuclear data library, KEDAK-3. Moreover, to some extent refined physical models were used and numerical methods were improved. MIGROS-3 allows the calculation of microscopic group cross sections of the ABBN type from isotopic neutron data given in KEDAK-format. All group constants, necessary for diffusion-, consistent P 1 - and Ssub(N)-calculations can be generated. Anisotropy of elastic scattering can be taken into account up to P 5 . A description of the code and the underlying theory is given. The input and output description, a sample problem and the program lists are provided. (orig.) [de

  19. Temporal formation of optical anisotropy and surface relief during polarization holographic recording in polymethylmethacrylate with azobenzene side groups

    Science.gov (United States)

    Sasaki, Tomoyuki; Izawa, Masahiro; Noda, Kohei; Nishioka, Emi; Kawatsuki, Nobuhiro; Ono, Hiroshi

    2014-03-01

    The formation of polarization holographic gratings with both optical anisotropy and surface relief (SR) deformation was studied for polymethylmethacrylate with azobenzene side groups. Temporal contributions of isotropic and anisotropic phase gratings were simultaneously determined by observing transitional intensity and polarization states of the diffraction beams and characterizing by means of Jones calculus. To clarify the mechanism of SR deformation, cross sections of SR were characterized based on the optical gradient force model; experimental observations were in good agreement with the theoretical expectation. We clarified that the anisotropic phase change originating in the reorientation of the azobenzene side groups was induced immediately at the beginning of the holographic recording, while the response time of the isotropic phase change originating in the molecular migration due to the optical gradient force was relatively slow.

  20. The star formation histories of local group dwarf galaxies. I. Hubble space telescope/wide field planetary camera 2 observations

    Energy Technology Data Exchange (ETDEWEB)

    Weisz, Daniel R. [Department of Astronomy, University of California at Santa Cruz, 1156 High Street, Santa Cruz, CA 95064 (United States); Dolphin, Andrew E. [Raytheon Company, 1151 East Hermans Road, Tucson, AZ 85756 (United States); Skillman, Evan D. [Minnesota Institute for Astrophysics, University of Minnesota, 116 Church Street SE, Minneapolis, MN 55455 (United States); Holtzman, Jon [Department of Astronomy, New Mexico State University, Box 30001, 1320 Frenger Street, Las Cruces, NM 88003 (United States); Gilbert, Karoline M.; Dalcanton, Julianne J.; Williams, Benjamin F., E-mail: drw@ucsc.edu [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States)

    2014-07-10

    We present uniformly measured star formation histories (SFHs) of 40 Local Group (LG) dwarf galaxies based on color-magnitude diagram (CMD) analysis from archival Hubble Space Telescope imaging. We demonstrate that accurate SFHs can be recovered from CMDs that do not reach the oldest main sequence turn-off (MSTO), but emphasize that the oldest MSTO is critical for precisely constraining the earliest epochs of star formation. We find that: (1) the average lifetime SFHs of dwarf spheroidals (dSphs) can be approximated by an exponentially declining SFH with τ ∼ 5 Gyr; (2) lower luminosity dSphs are less likely to have extended SFHs than more luminous dSphs; (3) the average SFHs of dwarf irregulars (dIrrs), transition dwarfs, and dwarf ellipticals can be approximated by the combination of an exponentially declining SFH (τ ∼ 3-4 Gyr) for lookback ages >10-12 Gyr ago and a constant SFH thereafter; (4) the observed fraction of stellar mass formed prior to z = 2 ranges considerably (80% for galaxies with M < 10{sup 5} M{sub ☉} to 30% for galaxies with M > 10{sup 7} M{sub ☉}) and is largely explained by environment; (5) the distinction between 'ultra-faint' and 'classical' dSphs is arbitrary; (6) LG dIrrs formed a significantly higher fraction of stellar mass prior to z = 2 than the Sloan Digital Sky Survey galaxies from Leitner and the SFHs from the abundance matching models of Behroozi et al. This may indicate higher than expected star formation efficiencies at early times in low mass galaxies. Finally, we provide all the SFHs in tabulated electronic format for use by the community.

  1. The star formation histories of local group dwarf galaxies. I. Hubble space telescope/wide field planetary camera 2 observations

    International Nuclear Information System (INIS)

    Weisz, Daniel R.; Dolphin, Andrew E.; Skillman, Evan D.; Holtzman, Jon; Gilbert, Karoline M.; Dalcanton, Julianne J.; Williams, Benjamin F.

    2014-01-01

    We present uniformly measured star formation histories (SFHs) of 40 Local Group (LG) dwarf galaxies based on color-magnitude diagram (CMD) analysis from archival Hubble Space Telescope imaging. We demonstrate that accurate SFHs can be recovered from CMDs that do not reach the oldest main sequence turn-off (MSTO), but emphasize that the oldest MSTO is critical for precisely constraining the earliest epochs of star formation. We find that: (1) the average lifetime SFHs of dwarf spheroidals (dSphs) can be approximated by an exponentially declining SFH with τ ∼ 5 Gyr; (2) lower luminosity dSphs are less likely to have extended SFHs than more luminous dSphs; (3) the average SFHs of dwarf irregulars (dIrrs), transition dwarfs, and dwarf ellipticals can be approximated by the combination of an exponentially declining SFH (τ ∼ 3-4 Gyr) for lookback ages >10-12 Gyr ago and a constant SFH thereafter; (4) the observed fraction of stellar mass formed prior to z = 2 ranges considerably (80% for galaxies with M < 10 5 M ☉ to 30% for galaxies with M > 10 7 M ☉ ) and is largely explained by environment; (5) the distinction between 'ultra-faint' and 'classical' dSphs is arbitrary; (6) LG dIrrs formed a significantly higher fraction of stellar mass prior to z = 2 than the Sloan Digital Sky Survey galaxies from Leitner and the SFHs from the abundance matching models of Behroozi et al. This may indicate higher than expected star formation efficiencies at early times in low mass galaxies. Finally, we provide all the SFHs in tabulated electronic format for use by the community.

  2. A green non-acid-catalyzed process for direct N=N-C group formation: comprehensive study, modeling, and optimization.

    Science.gov (United States)

    Khakyzadeh, Vahid; Zolfigol, Mohammad Ali; Derakhshan-Panah, Fatemeh; Jafarian, Majid; Miri, Mir Vahid; Gilandoust, Maryam

    2018-01-04

    The aim of this work is to introduce, model, and optimize a new non-acid-catalyzed system for a direct N[Formula: see text]N-C bond formation. By reacting naphthols or phenol with anilines in the presence of the sodium nitrite as nitrosonium ([Formula: see text] source and triethylammonium acetate (TEAA), a N[Formula: see text]N-C group can be formed in non-acid media. Modeling and optimization of the reaction conditions were investigated by response surface method. Sodium nitrite, TEAA, and water were chosen as variables, and reaction yield was also monitored. Analysis of variance indicates that a second-order polynomial model with F value of 35.7, a P value of 0.0001, and regression coefficient of 0.93 is able to predict the response. Based on the model, the optimum process conditions were introduced as 2.2 mmol sodium nitrite, 2.2 mL of TEAA, and 0.5 mL [Formula: see text] at room temperature. A quadratic (second-order) polynomial model, by analysis of variance, was able to predict the response for a direct N=N-C group formation. Predicted response values were in good agreement with the experimental values. Electrochemistry studies were done to introduce new Michael acceptor moieties. Broad scope, high yields, short reaction time, and mild conditions are some advantages of the presented method.

  3. How does the color influence figure and shape formation, grouping, numerousness and reading? The role of chromatic wholeness and fragmentation.

    Science.gov (United States)

    Pinna, Baingio; Uccula, Arcangelo; Tanca, Maria

    2010-09-01

    In this work it is suggested that color induces phenomenal wholeness, part-whole organization and fragmentation. The phenomenal wholeness subsumes the set of its main attributes: homogeneity, continuity, univocality, belongingness, and oneness. If color induces wholeness, it can also induce fragmentation. Therefore, in order to understand the role played by color within the process of part-whole organization, color is used both as a wholeness and as a fragmentation tool, thus operating synergistically or antagonistically with other wholeness processes. Therefore, color is expected to influence figure-ground segregation, grouping, shape formation and other visual processes that are related to the phenomenal wholeness. The purpose of this study is to rate the influence of color in inducing whole and part-whole organization and, consequently, in determining the perception of figure-ground segregation, grouping, shape formation, numerousness evaluation and time reading. We manipulated experimental conditions by using equiluminant colors to favor or break (parcel-out) the wholeness of objects like geometrical composite figures and words. The results demonstrated that color is aimed, among other psychological and biological purposes, at: (1) relating each chromatic component of an object, thus favoring the emergence of the whole object; (2) eliciting a part-whole organization, whose components are interdependent; (3) eliciting fragments and then breaking up the whole and favoring the emergence of single components. Wholeness, part-whole organization and fragmentation can be considered as three further purposes of color. © 2010 The Authors, Ophthalmic and Physiological Optics © 2010 The College of Optometrists.

  4. Subsea Permafrost Mapped Across the U.S. Beaufort Sea Using Multichannel Seismic Data

    Science.gov (United States)

    Brothers, L.; Hart, P. E.; Ruppel, C. D.

    2011-12-01

    Circum-Arctic continental shelves at water depths less than ~100 m were subaerial permafrost prior to the onset of sea-level rise starting in the late Pleistocene. Rapid transgression and the resulting temperature increase at the sediment surface have led to thawing of the inundated permafrost, landward retreat of the leading edge of the permafrost, and dissociation of permafrost-associated gas hydrates. Past numerical modeling has shown that gas hydrate dissociation is particularly pronounced at the permafrost-to-no permafrost transition offshore. On the U.S. Beaufort margin, subsea permafrost has never been systematically mapped, and the best insights about permafrost and associated gas hydrate have been based on a limited number of offshore boreholes and numerical studies, with sometimes contrasting predictions of the permafrost's seaward extent. We bring together 5370 km of multichannel seismic (MCS) data acquired during various proprietary exploration industry and public domain government surveys between 1977 and 1992 to map a velocity anomaly diagnostic of submerged permafrost along 500 km of the US Beaufort coastline. These high-velocity (>~2.8 km/s) refractions (HVR), which are evident in prestack MCS shot records, reveal laterally continuous layers of shallow, ice-bonded, coarse-grained sediments beneath the inner continental shelf. The HVR occur in less than 5% of the tracklines, and calculated HVR depths range from 60 to 350 m below seafloor. The velocity anomaly is not observed seaward of the 20 m isobath, and is only found within 30 km of the current shoreline. These results can be used to: 1) create a map of the minimum distribution of remaining US Beaufort shelf subsea permafrost; 2) reconcile discrepancies between model-predicted and borehole-verified offshore permafrost distribution; and 3) constrain where to expect hydrate dissociation.

  5. Healthy Body Image Intervention Delivered to Young Women via Facebook Groups: Formative Study of Engagement and Acceptability.

    Science.gov (United States)

    Stapleton, Jerod L; Manne, Sharon L; Day, Ashley K; Levonyan-Radloff, Kristine; Pagoto, Sherry L

    2018-02-20

    There is increasing interest in using social media sites such as Facebook to deliver health interventions so as to expose people to content while they are engaging in their usual social media habit. This formative intervention development study is novel in describing a preliminary test of using the secret group feature of Facebook to deliver a behavioral intervention targeting users of indoor tanning beds to reduce their risk of skin cancer. Intervention content was designed to challenge body image-related constructs associated with indoor tanning through the use of dissonance-inducing content. To evaluate engagement with and acceptability of using a secret Facebook group to deliver a healthy body image intervention to young women engaged in indoor tanning. Seventeen young women completed a baseline survey and joined a secret Facebook group with intervention content delivered via daily posts for 4 weeks. Engagement data was extracted and acceptability was measured via a follow-up survey. The study had a high retention rate (94%, [16/17]). On average, posts were viewed by 91% of participants, liked by 35%, and commented on by 26%. The average comment rate was highest (65%) for posts that elicited comments by directly posing questions or discussion topics to the group. Average intervention acceptability ratings were highly positive and participants reported feeling connected to the group and its topic. Average rates of past 1-month indoor tanning reported following the intervention were lower than the baseline rate (P=.08, Cohen d=0.47). This study is novel in demonstrating participant engagement with and acceptability of using Facebook secret groups to deliver a dissonance-inducing intervention approach that utilizes group-based discussions related to body image. The study is also unique within the field of skin cancer prevention by demonstrating the potential value of delivering an indoor tanning intervention within an interactive social media format. The findings

  6. Healthy Body Image Intervention Delivered to Young Women via Facebook Groups: Formative Study of Engagement and Acceptability

    Science.gov (United States)

    Manne, Sharon L; Day, Ashley K; Levonyan-Radloff, Kristine; Pagoto, Sherry L

    2018-01-01

    Background There is increasing interest in using social media sites such as Facebook to deliver health interventions so as to expose people to content while they are engaging in their usual social media habit. This formative intervention development study is novel in describing a preliminary test of using the secret group feature of Facebook to deliver a behavioral intervention targeting users of indoor tanning beds to reduce their risk of skin cancer. Intervention content was designed to challenge body image-related constructs associated with indoor tanning through the use of dissonance-inducing content. Objective To evaluate engagement with and acceptability of using a secret Facebook group to deliver a healthy body image intervention to young women engaged in indoor tanning. Methods Seventeen young women completed a baseline survey and joined a secret Facebook group with intervention content delivered via daily posts for 4 weeks. Engagement data was extracted and acceptability was measured via a follow-up survey. Results The study had a high retention rate (94%, [16/17]). On average, posts were viewed by 91% of participants, liked by 35%, and commented on by 26%. The average comment rate was highest (65%) for posts that elicited comments by directly posing questions or discussion topics to the group. Average intervention acceptability ratings were highly positive and participants reported feeling connected to the group and its topic. Average rates of past 1-month indoor tanning reported following the intervention were lower than the baseline rate (P=.08, Cohen d=0.47). Conclusions This study is novel in demonstrating participant engagement with and acceptability of using Facebook secret groups to deliver a dissonance-inducing intervention approach that utilizes group-based discussions related to body image. The study is also unique within the field of skin cancer prevention by demonstrating the potential value of delivering an indoor tanning intervention within

  7. NOGAP B-6. Vol. 9, Hydrocarbon determinations; Mackenzie River and Beaufort Sea

    International Nuclear Information System (INIS)

    Yunker, M.B.; McLaughlin, F.A.; Fowler, B.R.; Brooks, G.; Chiddell, G.; Hamilton, C.; Macdonald, R.W.

    1992-01-01

    As part of the Northern Oil and Gas Action Program, with major objectives to determine hydrocarbon pathways and primary productivity of waters overlying the Mackenzie Shelf, hydrocarbon samples were collected from the Mackenzie Delta, the Beaufort Sea coast, and from repeat sampling of several transects extending from inshore waters to the shelf break. Methods used for sample collection, extraction, and fractionation are described, as well as analytical techniques used. The bulk of this report consists of the analytical results, presented in tabular and graphic form, for alkanes, alkenes, hopanes and other triterpenes, polycyclic aromatic hydrocarbons, alcohols, and sterols. 30 refs., 2 figs., 5 tabs

  8. Environment of deposition and stratigraphy of the uranium-bearing strata around Beaufort West, South Africa

    International Nuclear Information System (INIS)

    Horowitz, A.

    1976-04-01

    Palynological analyses of some 50 samples collected from uranium-bearing strata - as well as the layers immediately above and below them - around Beaufort West, South Africa, indicate that these sediments were laid down in a wide, rather shallow delta in Late Permian times. Most of the sediments are fluvio-deltaic, and most of the plant remains were transported from the north, the hinterland in those times. A considerable percentage of the microfossils, e.g. Veryhachium and hystrichospheres, are clearly from a marine environment. The occurrence of marine microfossils in the spectrum, as compared with those of terrestrial provenance, increases considerably southwards [af

  9. Personality, Parasites, Political Attitudes, and Cooperation: A Model of How Infection Prevalence Influences Openness and Social Group Formation.

    Science.gov (United States)

    Brown, Gordon D A; Fincher, Corey L; Walasek, Lukasz

    2016-01-01

    What is the origin of individual differences in ideology and personality? According to the parasite stress hypothesis, the structure of a society and the values of individuals within it are both influenced by the prevalence of infectious disease within the society's geographical region. High levels of infection threat are associated with more ethnocentric and collectivist social structures and greater adherence to social norms, as well as with socially conservative political ideology and less open but more conscientious personalities. Here we use an agent-based model to explore a specific opportunities-parasites trade-off (OPTO) hypothesis, according to which utility-maximizing agents place themselves at an optimal point on a trade-off between (a) the gains that may be achieved through accessing the resources of geographically or socially distant out-group members through openness to out-group interaction, and (b) the losses arising due to consequently increased risks of exotic infection to which immunity has not been developed. We examine the evolution of cooperation and the formation of social groups within social networks, and we show that the groups that spontaneously form exhibit greater local rather than global cooperative networks when levels of infection are high. It is suggested that the OPTO model offers a first step toward understanding the specific mechanisms through which environmental conditions may influence cognition, ideology, personality, and social organization. Copyright © 2015 The Authors. Topics in Cognitive Science published by Wiley Periodicals, Inc. on behalf of Cognitive Science Society.

  10. Biofilm formation of beta-hemolytic group G Streptococcus dysgalactiae subspecies equisimilis isolates and its association with emm polymorphism.

    Science.gov (United States)

    Ma, Jui-Shan; Chen, Sin-Yu; Lo, Hsueh-Hsia

    2017-11-01

    Biofilm formation has been well known as a determinant of bacterial virulence. Group G Streptococcus dysgalactiae subspecies equisimilis (SDSE), a relevant pathogen with increasing medical importance, was evaluated for the biofilm-forming potential. Microtiter plate assay was used to assess the most feasible medium for group G SDSE to form a biofilm. Among 246 SDSE isolates examined, 46.7%, 43.5%, 33.3%, and 26.4% of isolates showed moderate or strong biofilm-forming abilities using tryptic soy broth (TSB), brain heart infusion broth (BHI), Todd-Hewitt broth (THB), and C medium with 30 mM glucose (CMG), respectively. The addition of glucose significantly increased the biofilm-forming ability of group G SDSE. FCT (fibronectin-collagen-T-antigen) typing of SDSE was first undertaken and 11 FCT types were found. Positive associations of stG10.0 or negative associations of stG245.0, stG840.0, and stG6.1 with biofilm-forming ability of SDSE were, respectively, found. This was the first investigation demonstrating biofilm-forming potential in clinical group G SDSE isolates; also, some significant associations of biofilm-forming ability with certain emm types were presented. © 2017 APMIS. Published by John Wiley & Sons Ltd.

  11. Constraining the Nature of Dark Matter with the Star-formation History of the Faintest Local Group Dwarf Galaxy Satellites

    International Nuclear Information System (INIS)

    Chau, Alice; Mayer, Lucio; Governato, Fabio

    2017-01-01

    Λ warm dark matter (ΛWDM), realized by collisionless particles of 1–3 keV, has been proposed as an alternative scenario to Λ-Cold-Dark Matter (ΛCDM) for the dwarf galaxy scale discrepancies. We present an approach to test the viability of such WDM models using star-formation histories (SFHs) of the dwarf spheroidal galaxies (dSphs) in the Local Group. We compare their high-time-resolution SFHs with the collapse redshift of their dark halos in CDM and WDM. Collapse redshift is inferred after determining the subhalo infall mass. This is based on the dwarf current mass inferred from stellar kinematics, combined with cosmological simulation results on subhalo evolution. WDM subhalos close to the filtering mass scale, forming significantly later than CDM, are the most difficult to reconcile with early truncation of star formation ( z ≥ 3). The ultra-faint dwarfs (UFDs) provide the most stringent constraints. Using six UFDs and eight classical dSphs, we show that a 1 keV particle is strongly disfavored, consistently with other reported methods. Excluding other models is only hinted for a few UFDs. Other UFDs for which the lack of robust constraints on halo mass prevents us from carrying out our analysis rigorously, show a very early onset of star formation that will strengthen the constraints delivered by our method in the future. We discuss the various caveats, notably the low number of dwarfs with accurately determined SFHs and the uncertainties when determining the subhalo infall mass, most notably the baryonic physics. Our preliminary analysis may serve as a pathfinder for future investigations that will combine accurate SFHs for local dwarfs with direct analysis of WDM simulations with baryons.

  12. Constraining the Nature of Dark Matter with the Star-formation History of the Faintest Local Group Dwarf Galaxy Satellites

    Energy Technology Data Exchange (ETDEWEB)

    Chau, Alice; Mayer, Lucio [Center for Theoretical Astrophysics and Cosmology, Institute for Computational Science, University of Zurich, Winterthurerstrasse 190, CH-8057 Zürich (Switzerland); Governato, Fabio [Astronomy Department, University of Washington, Box 351580, Seattle, WA 98195-1580 (United States)

    2017-08-10

    Λ warm dark matter (ΛWDM), realized by collisionless particles of 1–3 keV, has been proposed as an alternative scenario to Λ-Cold-Dark Matter (ΛCDM) for the dwarf galaxy scale discrepancies. We present an approach to test the viability of such WDM models using star-formation histories (SFHs) of the dwarf spheroidal galaxies (dSphs) in the Local Group. We compare their high-time-resolution SFHs with the collapse redshift of their dark halos in CDM and WDM. Collapse redshift is inferred after determining the subhalo infall mass. This is based on the dwarf current mass inferred from stellar kinematics, combined with cosmological simulation results on subhalo evolution. WDM subhalos close to the filtering mass scale, forming significantly later than CDM, are the most difficult to reconcile with early truncation of star formation ( z ≥ 3). The ultra-faint dwarfs (UFDs) provide the most stringent constraints. Using six UFDs and eight classical dSphs, we show that a 1 keV particle is strongly disfavored, consistently with other reported methods. Excluding other models is only hinted for a few UFDs. Other UFDs for which the lack of robust constraints on halo mass prevents us from carrying out our analysis rigorously, show a very early onset of star formation that will strengthen the constraints delivered by our method in the future. We discuss the various caveats, notably the low number of dwarfs with accurately determined SFHs and the uncertainties when determining the subhalo infall mass, most notably the baryonic physics. Our preliminary analysis may serve as a pathfinder for future investigations that will combine accurate SFHs for local dwarfs with direct analysis of WDM simulations with baryons.

  13. A challenge to dSph formation models: are the most isolated Local Group dSph galaxies truly old?

    Science.gov (United States)

    Monelli, Matteo

    2017-08-01

    What is the origin of the different dwarf galaxy types? The classification into dwarf irregular (dIrr), spheroidal (dSph), and transition (dT) types is based on their present-day properties. However, star formation histories (SFHs) reconstructed from deep color-magnitude diagrams (CMDs) provide details on the early evolution of galaxies of all these types, and indicate only two basic evolutionary paths. One is characterized by a vigorous but brief initial star-forming event, and little or no star formation thereafter (fast evolution), and the other one by roughly continuous star formation until (nearly) the present time (slow evolution). These two paths do not map directly onto the dIrr, dT and dSph types. Thus, the present galaxy properties do not reflect their lifetime evolution. Since there are some indications that slow dwarfs were assembled in lower-density environments than fast dwarfs, Gallart et al (2015) proposed that the distinction between fast and slow dwarfs reflects the characteristic density of the environment where they formed. This scenario, and more generally scenarios where dSph galaxies formed through the interaction with a massive galaxy, are challenged by a small sample of extremely isolated dSph/dT in the outer fringes of the Local Group. This proposal targets two of these objects (VV124, KKR25) for which we will infer their SFH - through a novel technique that combines the information from their RR Lyrae stars and deep CMDs sampling the intermediate-age population - in order to test these scenarios. This is much less demanding on observing time than classical SFH derivation using full depth CMDs.

  14. Methodical aspects of group work organization of the trainees in the professional development programs in long distance format

    Directory of Open Access Journals (Sweden)

    Igor A. Valdman

    2017-01-01

    Full Text Available In Russia and abroad the teamwork gained popularity in the labor market as a form of collective interaction between multiprofessional groups of specialists in implementing business projects, carrying out research and development projects, designing technological solutions and creating innovative products. At the same time, in the educational practice, especially when using distant educational technologies, the command method of instruction is quite rare. The reason for this is that the teamwork in the implementation of educational programs requires fixating individual educational outcomes of each trainee, their contribution to the performance of the group task. It complicates the organization of the educational process. As the result, educational organizations do not often use this educational form because of the complexity of its application in the conduct of intermediate and final attestation.Research goal. search and validation of a problem solution that can be formulated as a contradiction between the need to perform group homework assignments in distant learning and the necessity to fix the individual educational results of each trainee for the purpose of intermediate and final attestation. The authors of the article offer basic methodological principles that allow finding the balance in-between the requirements of legislation and preserving the team approach in the process of group work of trainees.Materials and methods. The initial materials of the research are an overview of existing publications on the organization of teamwork of trainees is used, including the implementation of training in a long distance format, the legislation of the Russian Federation regarding interim and final certification of trainees, as well as practical experience in implementing training programs, based on ANO “E-learning for Nanoindustry (“eNano””. Based on these materials, the authors offer basic methodological principles, obtained empirically and

  15. SSX2 is a novel DNA-binding protein that antagonizes polycomb group body formation and gene repression

    DEFF Research Database (Denmark)

    Gjerstorff, Morten Frier; Relster, Mette Marie; Greve, Katrine Buch Viden

    2014-01-01

    Polycomb group (PcG) complexes regulate cellular identity through epigenetic programming of chromatin. Here, we show that SSX2, a germline-specific protein ectopically expressed in melanoma and other types of human cancers, is a chromatin-associated protein that antagonizes BMI1 and EZH2 PcG body...... formation and derepresses PcG target genes. SSX2 further negatively regulates the level of the PcG-associated histone mark H3K27me3 in melanoma cells, and there is a clear inverse correlation between SSX2/3 expression and H3K27me3 in spermatogenesis. However, SSX2 does not affect the overall composition...

  16. Ecological change drives a decline in mercury concentrations in southern Beaufort Sea polar bears

    Science.gov (United States)

    McKinney, Melissa A.; Atwood, Todd C.; Pedro, Sara; Peacock, Elizabeth

    2017-01-01

    We evaluated total mercury (THg) concentrations and trends in polar bears from the southern Beaufort Sea subpopulation from 2004 to 2011. Hair THg concentrations ranged widely among individuals from 0.6 to 13.3 μg g–1 dry weight (mean: 3.5 ± 0.2 μg g–1). Concentrations differed among sex and age classes: solitary adult females ≈ adult females with cubs ≈ subadults > adult males ≈ yearlings > cubs-of-the-year ≈ 2 year old dependent cubs. No variation was observed between spring and fall samples. For spring-sampled adults, THg concentrations declined by 13% per year, contrasting recent trends observed for other Western Hemispheric Arctic biota. Concentrations also declined by 15% per year considering adult males only, while a slower, nonsignificant decrease of 4.4% per year was found for adult females. Lower THg concentrations were associated with higher body mass index (BMI) and higher proportions of lower trophic position food resources consumed. Because BMI and diet were related, and the relationship to THg was strongest for BMI, trends were re-evaluated adjusting for BMI as the covariate. The adjusted annual decline was not significant. These findings indicate that changes in foraging ecology, not declining environmental concentrations of mercury, are driving short-term declines in THg concentrations in southern Beaufort Sea polar bears.

  17. Geochemical evidences of methane hydrate dissociation in Alaskan Beaufort Margin during Holocene

    Science.gov (United States)

    Uchida, M.; Rella, S.; Kubota, Y.; Kumata, H.; Mantoku, K.; Nishino, S.; Itoh, M.

    2017-12-01

    Alaskan Beaufort margin bear large abundances of sub-sea and permafrost methane hydrate[Ruppel, 2016]. During the Last Glacial, previous reported direct and indirect evidences accumulated from geochemical data from marginal sea sediment suggests that methane episodically released from hydrate trapped in the seafloor sediments[Kennett et al., 2000; Uchida et al., 2006, 2008; Cook et al, 2011]. Here we analyzed stable isotopes of foraminifera and molecular marker derived from the activity of methanotrophic bacteria from piston cores collected by the 2010 R/V Mirai cruise in Alaskan Beaufort Margin. Our data showed highly depleted 13C compositions of benthic foraminifera, suggesting indirect records of enhanced incorporation of 13C-depleted CO2 formed by methanotrophic process that use 12C-enriched methane as their main source of carbon. This is the first evidence of methane hydrate dissociation in Alaskan margin. Here we discussed timing of signals of methane dissociation with variability of sea ice and intermediate Atlantic water temperature. The dissociation of methane hydrate in the Alaskan Margin may be modulated by Atlantic warm intermediate water warming. Our results suggest that Arctic marginal regions bearing large amount methane hydrate may be a profound effect on future warming climate changes.

  18. Beaufort Sea oil spills state of knowledge review and identification of key issues

    International Nuclear Information System (INIS)

    Dickins, David; Devenis, Peter; Buist, Ian; Belore, Randy; Trudel, K.; Potter, S.

    2011-01-01

    The Arctic holds the world's largest remaining untapped gas reserves and some of its largest undeveloped oil reserves. A significant proportion of these reserves lie offshore, in the Arctic's shallow and biologically productive shelf seas. This paper describes the results of a recently-completed study commissioned by the environmental studies research funds to document the current state of knowledge with regard to counter-measures for oil spills that might result from exploration and production activities in the Canadian Beaufort Sea. It provides a brief overview of the main advances in the past 20 years and the state-of-the-art for each of the main categories of counter-measures. An additional goal of the study was to identify key issues of concern regarding planning and response to spills in the Beaufort, to provide a current reference document for use by industry, regulators and the public, and prepare a geographic database of coastal resources, vulnerabilities and sensitivities that may influence the choice of oil spill containment and recovery methods.

  19. Inferred gas hydrate and permafrost stability history models linked to climate change in the Beaufort-Mackenzie Basin, Arctic Canada

    Czech Academy of Sciences Publication Activity Database

    Majorowicz, J.; Šafanda, Jan; Osadetz, K.

    2012-01-01

    Roč. 8, č. 2 (2012), s. 667-682 ISSN 1814-9324 Institutional research plan: CEZ:AV0Z30120515 Institutional support: RVO:67985530 Keywords : climate change * Beaufort-Mackenzie Basin * permafrost Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 3.556, year: 2012

  20. Unusual C-C bond cleavage in the formation of amine-bis(phenoxy) group 4 benzyl complexes: Mechanism of formation and application to stereospecific polymerization

    KAUST Repository

    Gowda, Ravikumar R.

    2014-08-11

    Group 4 tetrabenzyl compounds MBn4 (M = Zr, Ti), upon protonolysis with an equimolar amount of the tetradentate amine-tris(phenol) ligand N[(2,4-tBu2C6H2(CH 2)OH]3 in toluene from -30 to 25 °C, unexpectedly lead to amine-bis(phenoxy) dibenzyl complexes, BnCH2N[(2,4- tBu2C6H2(CH2)O] 2MBn2 (M = Zr (1), Ti (2)) in 80% (1) and 75% (2) yields. This reaction involves an apparent cleavage of the >NCH2-ArOH bond (loss of the phenol in the ligand) and formation of the >NCH 2-CH2Bn bond (gain of the benzyl group in the ligand). Structural characterization of 1 by X-ray diffraction analysis confirms that the complex formed is a bis(benzyl) complex of Zr coordinated by a newly derived tridentate amine-bis(phenoxy) ligand arranged in a mer configuration in the solid state. The abstractive activation of 1 and 2 with B(C6F 5)3·THF in CD2Cl2 at room temperature generates the corresponding benzyl cations {BnCH2N[(2,4- tBu2C6H2(CH2)O] 2MBn(THF)}+[BnB(C6F5) 3]- (M = Zr (3), Ti, (4)). These cationic complexes, along with their analogues derived from (imino)phenoxy tri- and dibenzyl complexes, [(2,6-iPr2C6H3)N=C(3,5- tBu2C6H2)O]ZrBn3 (5) and [2,4-Br2C6H2(O)(6-CH2(NC 5H9))CH2N=CH(2-adamantyl-4-MeC 6H2O)]ZrBn2 (6), have been found to effectively polymerize the biomass-derived renewable β-methyl-α-methylene- γ-butyrolactone (βMMBL) at room temperature into the highly stereoregular polymer PβMMBL with an isotacticity up to 99% mm. A combined experimental and DFT study has yielded a mechanistic pathway for the observed unusual C-C bond cleavage in the present protonolysis reaction between ZrBn4 and N[(2,4-tBu2C 6H2(CH2)OH]3 for the formation of complex 1, which involves the benzyl radical and the Zr(III) species, resulting from thermal and photochemical decomposition of ZrBn4, followed by a series of reaction sequences consisting of protonolysis, tautomerization, H-transfer, oxidation, elimination, and radical coupling. © 2014 American Chemical Society.

  1. Arbuscular mycorrhizal fungi reveal distinct patterns of anastomosis formation and hyphal healing mechanisms between different phylogenic groups

    NARCIS (Netherlands)

    De Souza, F.A.; Fernández, F.; Delmas, N.S.; Declerck, S.

    2005-01-01

    The significance of anastomosis formation and the hyphal healing mechanism (HHM) for functionality and integrity of the arbuscular mycorrhizal (AM) fungal mycelial network remains poorly documented. Four Glomeraceae and three Gigasporaceae were cultured monoxenically. Anastomosis formation was

  2. Bowhead whale body condition and links to summer sea ice and upwelling in the Beaufort Sea

    Science.gov (United States)

    George, John C.; Druckenmiller, Matthew L.; Laidre, Kristin L.; Suydam, Robert; Person, Brian

    2015-08-01

    We examined the response of bowhead whale (Balaena mysticetus) body condition to summer sea ice conditions and upwelling-favorable winds. We used a long-term dataset collected from whales of the Bering-Chukchi-Beaufort Seas (BCB) stock to estimate various body condition indices (BCI's) for individual whales that were harvested by Alaskan Eskimos. A series of offshore regions frequented by bowhead whales in summer were delineated and used to quantify interannual summertime environmental conditions including: (a) mean open water fraction, (b) duration of melt season, (c) date of continuous freeze-up, and (d) mean upwelling-favorable wind stress. Body condition was analyzed relative to these metrics for both the preceding summer feeding season and the previous three seasons combined. Our analysis indicates a significant increase in the long-term trend in an axillary girth-based body condition index (BCIG) over the study period (1989-2011). The increase in BCIG is likely associated with the trend in overall reduction of sea ice, including increased duration of open water, changes in upwelling potential (wind stress), and possibly higher primary production in the Pacific Arctic marine ecosystem favoring water-column invertebrates. We found strong significant positive correlations between BCIG and late summer open water fraction in the Beaufort Sea and smaller nearshore areas off the Mackenzie Delta and west of Banks Island. Additionally, BCIG was positively and significantly correlated with duration of melt season, later date of freeze-up in the Beaufort Sea, and upwelling-favorable winds on the Mackenzie shelf and west of Banks Island. A strong seasonal difference in BCI's was noted for subadult bowheads, presumably associated with summer feeding; however, yearlings were found to drop in BCI over at least the first summer after weaning. Our results indicate an overall increase in bowhead whale body condition and a positive correlation with summer sea ice loss over the

  3. Temperature, salinity, and other data from buoy casts in the Arctic Ocean, Barents Sea and Beaufort Sea from 1948 to 1993 (NODC Accession 9800040)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature, salinity, and other data were collected using buoy casts in the Arctic Ocean, Barents Sea and Beaufort Sea from 1948 to 1993. Data were collected by the...

  4. Beaufort Gyre hydrographic data: Temperature, salinity and transmissivity data from the Louis S St. Laurent in the Arctic Ocean, 2003 - 2008 (NODC Accession 0058268)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The major goal of the observational program is to determine the variability of different components of the Beaufort Gyre fresh water (ocean and sea ice) system and...

  5. SBI AWS02-I Bottle and Nutrient Data collected from the Polar Star in the Beaufort and Chukchi Seas (NODC Accession 0001288)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The field phase of the Shelf-Basin Interactions Experiment (SBI) began in 2002 with a series of three cruises to the Chukchi and Beaufort Seas. SBI is a...

  6. Oceanographic data collected from the Sir John Franklin in the Beaufort Sea, September 1989

    Energy Technology Data Exchange (ETDEWEB)

    Macdonald, R W; Carmack, E C; O' Brien, M C; McLaughlin, F A; Minkley, B G; Berger-North, K

    1989-09-01

    The data reported here were collected from the Canadian Coast Guard ship Sir John Franklin during a cruise to the Canadian Beaufort Sea from August 21 to Sept 5, 1989. The cruise had two broad objectives: to collect chemical and conductivity temperature depth (CTD) data at a deep station in the Canadian Basin, and to survey intensively the shelf break with the Mackenzie Canyon as a focus. Conductivity temperature depth was measured using a CTD guideline system. Water samples consisting of hydrocast for 6 shelf edge stations at 200 m depth and one deep station at 3200 m depth were tested for salinity, temperature, dissolved oxygen, nutrients, and chlorophyll a. In addition, samples were collected for analysis of tritium, C-14, and oxygen isotope composition and acoustic profiles were run. Isotope composition and acoustic profile data are not included in this report.

  7. Salinity, temperature and density data for the Canadian Beaufort Sea shelf, March 1988

    Energy Technology Data Exchange (ETDEWEB)

    Hopky, G E; Chiperzak, D B; Lawrence, M J

    1988-01-01

    This report contains salinity, temperature and density (CTD) data collected in the waters of the Canadian Beaufort Sea Shelf during March 1988. Salinity and temperature profile data were measured using a Guildline Model 8870 probe deployed from the ice surface. Ice thickness was also measured. Density was calculated using salinity and temperature values. CTD profiles were measured at five stations. The maximum depths of profiles measured from the ice surface ranged from 31.2 to 16.8 dbar. Salinity and temperature measurements ranged from 0.35 to 34.83, and -1.87 to 1.08/sup 0/C, respectively. The data presented in this report will assist in the identification and delineation of potential habitat types, as part of the Critical Arctic Estuarine and Marine Habitat Project of the Northern Oil and Gas Program. 5 refs., 7 figs., 6 tabs.

  8. Minimum distribution of subsea ice-bearing permafrost on the US Beaufort Sea continental shelf

    Science.gov (United States)

    Brothers, Laura L.; Hart, Patrick E.; Ruppel, Carolyn D.

    2012-01-01

    Starting in Late Pleistocene time (~19 ka), sea level rise inundated coastal zones worldwide. On some parts of the present-day circum-Arctic continental shelf, this led to flooding and thawing of formerly subaerial permafrost and probable dissociation of associated gas hydrates. Relict permafrost has never been systematically mapped along the 700-km-long U.S. Beaufort Sea continental shelf and is often assumed to extend to ~120 m water depth, the approximate amount of sea level rise since the Late Pleistocene. Here, 5,000 km of multichannel seismic (MCS) data acquired between 1977 and 1992 were examined for high-velocity (>2.3 km s−1) refractions consistent with ice-bearing, coarse-grained sediments. Permafrost refractions were identified along sea ice-bearing permafrost, which does not extend seaward of 30 km offshore or beyond the 20 m isobath.

  9. Observational Inferences of Lateral Eddy Diffusivity in the Halocline of the Beaufort Gyre

    Science.gov (United States)

    Meneghello, Gianluca; Marshall, John; Cole, Sylvia T.; Timmermans, Mary-Louise

    2017-12-01

    Using Ekman pumping rates mediated by sea ice in the Arctic Ocean's Beaufort Gyre (BG), the magnitude of lateral eddy diffusivities required to balance downward pumping is inferred. In this limit—that of vanishing residual-mean circulation—eddy-induced upwelling exactly balances downward pumping. The implied eddy diffusivity varies spatially and decays with depth, with values of 50-400 m2/s. Eddy diffusivity estimated using mixing length theory applied to BG mooring data exhibits a similar decay with depth and range of values from 100 m2/s to more than 600 m2/s. We conclude that eddy diffusivities in the BG are likely large enough to balance downward Ekman pumping, arresting the deepening of the gyre and suggesting that eddies play a zero-order role in buoyancy and freshwater budgets of the BG.

  10. Translating group programmes into online formats: establishing the acceptability of a parents' sex and relationships communication serious game.

    Science.gov (United States)

    Bayley, Julie E; Brown, Katherine E

    2015-12-09

    to feedback text volume. A manualised group programme can be viably converted into a serious game format which is both cognitively and emotionally acceptable. The intervention may be more effectively targeted at parents with younger children, and further game developments must particularly address information dosing. Establishing the viability of digitally converting a group programme is a significant step forward for implementation focused research.

  11. A new squamate lizard from the Upper Cretaceous Adamantina Formation (Bauru Group, São Paulo State, Brazil

    Directory of Open Access Journals (Sweden)

    William R. Nava

    2011-03-01

    Full Text Available The record of non-mosasaur squamates (Reptilia, Squamata is sparse in the Cretaceus fossil record of Brazil and include six putative reports, three from the Aptian-Albian of the Araripe Basin (Tijubina pontei Bonfim-Júnior and Marques, Olindalacerta brasiliensis Evans and Yabumoto, and a lizard indet. and three from the Upper Cretaceous of the Bauru Group (Pristiguana brasiliensis Estes and Price, Anilioidae gen. et sp. indet., and Squamata gen. et sp. indet.. In this contribution, a new genus and species of lizard, Brasiliguana prudentis gen. et sp. nov., is described based on an isolated left maxilla with teeth. The material was discovered in an outcrop of the Upper Cretaceous Adamantina Formation (Bauru Group located in the proximity of Presidente Prudente Municipality, São Paulo State, Brazil. The new taxon is considered a basal non-Priscagamidae+Acrodonta iguanian based on the presence of a weakly inclined anterior margin of the maxillary nasal process and maxillary tooth shape and tooth implantation similar to that of iguanians rather than of other lizard groups (e.g. teiids. This finding significantly increases the squamate lizard diversity of South America, which is still poorly understood and sparsely represented in the fossil record.Os achados de escamados (Reptilia, Squamata são escassos no Cretáceo do Brasil, incluindo cinco registros pontuais, dois do Aptiano-Albiano da Bacia do Araripe (Tijubina pontei Bonfim-Júnior e Marques e Olindalacerta brasiliensis Evans e Yabumoto, e três do Cretáceo Superior do Grupo Bauru (Pristiguana brasiliensis Estes and Price, Anilioidae gen. et sp. indet., Squamata gen. et sp. indet.. Nesta contribuição apresentamos um novo gênero e espécie de lagarto, Brasiliguana prudentis, baseado numa maxila esquerda com dentição. O material provém de depósitos da Formação Adamantina aflorantes próximos a cidade de Presidente Prudente, Estado de São Paulo, Brasil. O novo táxon é considerado um

  12. Geotechnical conditions and ice loading for an offshore drilling platform in the Canadian Beaufort Sea

    Energy Technology Data Exchange (ETDEWEB)

    Martens, S.; Eshraghian, A.; Rogers, B. [Klohn Crippen Berger Ltd., Calgary, AB (Canada)

    2009-07-01

    This paper addressed the geotechnical aspects of the deployment of the steel drilling caisson (SDC) at the Paktoa site in the Canadian Beaufort Sea. The SDC is a bottom founded mobile offshore drilling platform that can operate in 8 to 25 m of water in an Arctic environment. It is mated to a submersible barge in order to resist large ice forces on the structure at sites with relatively weak soils, without the need for site preparation. To date, the SDC has been deployed at 8 sites in the Canadian and Alaskan Beaufort Sea. This paper focused on the Paktoa location, where the SDC was deployed 50 km offshore in a water depth of 14 m during the winter of 2005-2006. Geotechnical investigations were conducted from the landfast ice prior to deployment and from the SDC deck. This paper described the soil properties and design loading; design stability; and deformation analysis. The environmental loads considered for the SDC design included ice push, waves and earthquakes. The ice loading was the dominant loading case. The instrumentation installed in the seabed included 2 push-in piezometers and an inclinometer. An ice loading event in February 2006 resulted in considerable displacements in the in-place inclinometer string below the SDC. Several analysis methods were used to estimate the magnitude of the ice load during this event in order to better understand the magnitude of ice loading for future Arctic deployments of gravity based drilling platforms. It was concluded that further deployments should have a minimum of 2 and preferably 4 in-place inclinometer strings to measure real-time deformation of the seabed to enable measurement of rotation of the structure that may occur due to asymmetrical ice loading. 10 refs., 2 tabs., 15 figs.

  13. The first hop: Use of Beaufort Sea deltas by hatch-year semipalmated sandpipers

    Science.gov (United States)

    Churchwell, Roy T.; Kendall, Steve J.; Brown, Stephen C.; Blanchard, Arny L.; Hollmen, Tuula E.; Powell, Abby

    2018-01-01

    River deltas along Alaska’s Beaufort Sea coast are used by hatch-year semipalmated sandpipers (Calidris pusilla) after leaving their terrestrial natal sites, but the drivers of their use of these stopover sites on the first “hop” of fall migration are unknown. We quantified sandpiper temporal distribution and abundance as related to food resources at three river deltas during the beginning of their fall migration (post-breeding period) to compare the habitat quality among these deltas. We conducted population counts, sampled invertebrates, and captured birds to collect blood samples from individuals for triglyceride and stable isotope analyses to determine fattening rates and diet. Patterns of sandpiper and invertebrate abundance were complex and varied among deltas and within seasons. River deltas were used by sandpipers from late July to late August, and peak sandpiper counts ranged from 1000 to 4000 individuals, of which 98% were hatch-year semipalmated sandpipers. Isotopic signatures from blood plasma samples indicated that birds switched from a diet of upland tundra to delta invertebrate taxa as the migration season progressed, suggesting a dependence on delta invertebrates. Despite differences in diet among deltas, we found no differences in fattening rates of juvenile sandpipers as indicated by triglyceride levels. The number of sandpipers was positively associated with abundance of Amphipoda and Oligochaeta at the Jago and Okpilak-Hulahula deltas; an isotopic mixing model indicated that sandpipers consumed Amphipoda and Oligochaeta at Jago, mostly Chironomidae at Okpilak-Hulahula and Spionidae at Canning. Regardless of the difference in sandpiper diets at the Beaufort Sea deltas, their similar fattening rates throughout the season indicate that all of these stopover sites provide a critical food resource for hatch-year sandpipers beginning their first migration.

  14. Polar bear population dynamics in the southern Beaufort Sea during a period of sea ice decline.

    Science.gov (United States)

    Bromaghin, Jeffrey F; Mcdonald, Trent L; Stirling, Ian; Derocher, Andrew E; Richardson, Evan S; Regehr, Eric V; Douglas, David C; Durner, George M; Atwood, Todd; Amstrup, Steven C

    2015-04-01

    In the southern Beaufort Sea of the United States and Canada, prior investigations have linked declines in summer sea ice to reduced physical condition, growth, and survival of polar bears (Ursus maritimus). Combined with projections of population decline due to continued climate warming and the ensuing loss of sea ice habitat, those findings contributed to the 2008 decision to list the species as threatened under the U.S. Endangered Species Act. Here, we used mark-recapture models to investigate the population dynamics of polar bears in the southern Beaufort Sea from 2001 to 2010, years during which the spatial and temporal extent of summer sea ice generally declined. Low survival from 2004 through 2006 led to a 25-50% decline in abundance. We hypothesize that low survival during this period resulted from (1) unfavorable ice conditions that limited access to prey during multiple seasons; and possibly, (2) low prey abundance. For reasons that are not clear, survival of adults and cubs began to improve in 2007 and abundance was comparatively stable from 2008 to 2010, with ~900 bears in 2010 (90% CI 606-1212). However, survival of subadult bears declined throughout the entire period. Reduced spatial and temporal availability of sea ice is expected to increasingly force population dynamics of polar bears as the climate continues to warm. However, in the short term, our findings suggest that factors other than sea ice can influence survival. A refined understanding of the ecological mechanisms underlying polar bear population dynamics is necessary to improve projections of their future status and facilitate development of management strategies.

  15. Age and sex composition of seals killed by polar bears in the eastern Beaufort Sea.

    Directory of Open Access Journals (Sweden)

    Nicholas W Pilfold

    Full Text Available Polar bears (Ursus maritimus of the Beaufort Sea enter hyperphagia in spring and gain fat reserves to survive periods of low prey availability. We collected information on seals killed by polar bears (n=650 and hunting attempts on ringed seal (Pusa hispida lairs (n=1396 observed from a helicopter during polar bear mark-recapture studies in the eastern Beaufort Sea in spring in 1985-2011. We investigated how temporal shifts in ringed seal reproduction affect kill composition and the intraspecific vulnerabilities of ringed seals to polar bear predation.Polar bears primarily preyed on ringed seals (90.2% while bearded seals (Erignathus barbatus only comprised 9.8% of the kills, but 33% of the biomass. Adults comprised 43.6% (150/344 of the ringed seals killed, while their pups comprised 38.4% (132/344. Juvenile ringed seals were killed at the lowest proportion, comprising 18.0% (62/344 of the ringed seal kills. The proportion of ringed seal pups was highest between 2007-2011, in association with high ringed seal productivity. Half of the adult ringed seal kills were ≥ 21 years (60/121, and kill rates of adults increased following the peak of parturition. Determination of sex from DNA revealed that polar bears killed adult male and adult female ringed seals equally (0.50, n=78. The number of hunting attempts at ringed seal subnivean lair sites was positively correlated with the number of pup kills (r(2 =0.30, P=0.04, but was not correlated with the number of adult kills (P=0.37.Results are consistent with decadal trends in ringed seal productivity, with low numbers of pups killed by polar bears in spring in years of low pup productivity, and conversely when pup productivity was high. Vulnerability of adult ringed seals to predation increased in relation to reproductive activities and age, but not gender.

  16. Polar bear population dynamics in the southern Beaufort Sea during a period of sea ice decline

    Science.gov (United States)

    Bromaghin, Jeffrey F.; McDonald, Trent L.; Stirling, Ian; Derocher, Andrew E.; Richardson, Evan S.; Regehr, Eric V.; Douglas, David C.; Durner, George M.; Atwood, Todd C.; Amstrup, Steven C.

    2015-01-01

    In the southern Beaufort Sea of the United States and Canada, prior investigations have linked declines in summer sea ice to reduced physical condition, growth, and survival of polar bears (Ursus maritimus). Combined with projections of population decline due to continued climate warming and the ensuing loss of sea ice habitat, those findings contributed to the 2008 decision to list the species as threatened under the U.S. Endangered Species Act. Here, we used mark–recapture models to investigate the population dynamics of polar bears in the southern Beaufort Sea from 2001 to 2010, years during which the spatial and temporal extent of summer sea ice generally declined. Low survival from 2004 through 2006 led to a 25–50% decline in abundance. We hypothesize that low survival during this period resulted from (1) unfavorable ice conditions that limited access to prey during multiple seasons; and possibly, (2) low prey abundance. For reasons that are not clear, survival of adults and cubs began to improve in 2007 and abundance was comparatively stable from 2008 to 2010, with ~900 bears in 2010 (90% CI 606–1212). However, survival of subadult bears declined throughout the entire period. Reduced spatial and temporal availability of sea ice is expected to increasingly force population dynamics of polar bears as the climate continues to warm. However, in the short term, our findings suggest that factors other than sea ice can influence survival. A refined understanding of the ecological mechanisms underlying polar bear population dynamics is necessary to improve projections of their future status and facilitate development of management strategies.

  17. Monitoring hydrocarbons and trace metals in Beaufort Sea sediments and organisms. Final report

    International Nuclear Information System (INIS)

    Boehm, P.; LeBlanc, L.; Trefry, J.; Marajh-Whittemore, P.; Brown, J.

    1990-01-01

    As part of the Minerals Management Service's environmental studies of oil and gas exploration and production activities in the Alaskan Beaufort Sea, a study was conducted in 1989 to monitor the marine environment for inputs of chemicals related to drilling and exploration. The 1989 Beaufort Sea Monitoring Program (BSMP) was designed to monitor sediments and selected benthic organisms for trace metals and hydrocarbons so as to infer any changes that might have resulted from drilling and production activities. A series of 49 stations were sampled during the program. The study area extended from Cape Halkett on the western end of Harrison Bay to Griffin Point, east of Barter Island. The sampling design combined an area-wide approach in which stations were treated as replicates of 8 specific geographic regions, with an activity-specific approach, which focused on the potential establishment of metal or hydrocarbon concentration gradients with distance from the Endicott Production Field in Prudhoe Bay. The analytical program focused on the analysis of the fine-fraction of the sediment for a series of trace metals and elements and the analysis of a suite of saturated and aromatic hydrocarbons in the bulk sediment. The total organic carbon (TOB) content and the grain size distribution in the sediments were determined as well. Benthic bivalve molluscs, representative of several feeding types were collected from those stations for which data previously existed from the 1984-1986 BSMP, and were analyzed for metals and saturated and aromatic hydrocarbons. The benthic amphipods were collected, pooled by station or region, and analyzed as well

  18. Age and sex composition of seals killed by polar bears in the eastern Beaufort Sea.

    Science.gov (United States)

    Pilfold, Nicholas W; Derocher, Andrew E; Stirling, Ian; Richardson, Evan; Andriashek, Dennis

    2012-01-01

    Polar bears (Ursus maritimus) of the Beaufort Sea enter hyperphagia in spring and gain fat reserves to survive periods of low prey availability. We collected information on seals killed by polar bears (n=650) and hunting attempts on ringed seal (Pusa hispida) lairs (n=1396) observed from a helicopter during polar bear mark-recapture studies in the eastern Beaufort Sea in spring in 1985-2011. We investigated how temporal shifts in ringed seal reproduction affect kill composition and the intraspecific vulnerabilities of ringed seals to polar bear predation. Polar bears primarily preyed on ringed seals (90.2%) while bearded seals (Erignathus barbatus) only comprised 9.8% of the kills, but 33% of the biomass. Adults comprised 43.6% (150/344) of the ringed seals killed, while their pups comprised 38.4% (132/344). Juvenile ringed seals were killed at the lowest proportion, comprising 18.0% (62/344) of the ringed seal kills. The proportion of ringed seal pups was highest between 2007-2011, in association with high ringed seal productivity. Half of the adult ringed seal kills were ≥ 21 years (60/121), and kill rates of adults increased following the peak of parturition. Determination of sex from DNA revealed that polar bears killed adult male and adult female ringed seals equally (0.50, n=78). The number of hunting attempts at ringed seal subnivean lair sites was positively correlated with the number of pup kills (r(2) =0.30, P=0.04), but was not correlated with the number of adult kills (P=0.37). Results are consistent with decadal trends in ringed seal productivity, with low numbers of pups killed by polar bears in spring in years of low pup productivity, and conversely when pup productivity was high. Vulnerability of adult ringed seals to predation increased in relation to reproductive activities and age, but not gender.

  19. Permian plants from the Chutani Formation (Titicaca Group, Northern Altiplano of Bolivia: I. Genera Pecopteris and Asterotheca

    Directory of Open Access Journals (Sweden)

    Carlos E. L. Vieira

    2004-03-01

    Full Text Available Fossil plants belonging to the morphogenera Glossopteris, Pecopteris and Asterotheca were collected from the upper part of the Chutani Formation (Titicaca Group, near the town of San Pablo de Tiquina, on the southeastern shore of Lake Titicaca (northern Altiplano, Bolivia. Here we report the analysis of fern-type foliage found at this location. Three species of pecopterid fronds are identified: Pecopteris dolianitii Rohn and Rösler, P. cf. P. cadeadensis Rohn and Rösler, and P. cf. P. pedrasica Read. All these species are typically found in Permian deposits of the Paraná Basin in southern Brazil. Despite the poor preservation of the material, a fertile specimen could be studied and was determined as Asterotheca sp. The paleoenvironmental and paleoecological implications of this new find are briefly analyzed.Plantas fósseis, pertencentes aos morfo-gêneros Glossopteris, Pecopteris e Asterotheca, foram coletadas na porção superior da seção aflorante da Formação Chutani, próxima ao povoado de San Pablo de Tiquina, sudeste do lago Titicaca (Altiplano norte, Bolívia. Este trabalho analisa folhagens do tipo feto encontradas neste sítio. Entre os espécimes estéreis, três espécies de frondes pecopterídeas foram identificadas: Pecopteris dolianiti, P. cf. cadeadensis e P. cf. pedrasica. Todas essas espécies eram até agora restritas aos depósitos permianos da Bacia do Paraná. A despeito do estado de preservação ruim do material, um espécime fértil pôde ser determinado como pertencente ao gênero Asterotheca. Implicações paleoambientais e paleoecológicas deste novo achado são brevemente analisadas.

  20. Barriers to Medication Decision Making in Women with Lupus Nephritis: A Formative Study using Nominal Group Technique.

    Science.gov (United States)

    Singh, Jasvinder A; Qu, Haiyan; Yazdany, Jinoos; Chatham, Winn; Dall'era, Maria; Shewchuk, Richard M

    2015-09-01

    To assess the perspectives of women with lupus nephritis on barriers to medication decision making. We used the nominal group technique (NGT), a structured process to elicit ideas from participants, for a formative assessment. Eight NGT meetings were conducted in English and moderated by an expert NGT researcher at 2 medical centers. Participants responded to the question: "What sorts of things make it hard for people to decide to take the medicines that doctors prescribe for treating their lupus kidney disease?" Patients nominated, discussed, and prioritized barriers to decisional processes involving medications for treating lupus nephritis. Fifty-one women with lupus nephritis with a mean age of 40.6 ± 13.3 years and disease duration of 11.8 ± 8.3 years participated in 8 NGT meetings: 26 African Americans (4 panels), 13 Hispanics (2 panels), and 12 whites (2 panels). Of the participants, 36.5% had obtained at least a college degree and 55.8% needed some help in reading health materials. Of the 248 responses generated (range 19-37 responses/panel), 100 responses (40%) were perceived by patients as having relatively greater importance than other barriers in their own decision-making processes. The most salient perceived barriers, as indicated by percent-weighted votes assigned, were known/anticipated side effects (15.6%), medication expense/ability to afford medications (8.2%), and the fear that the medication could cause other diseases (7.8%). Women with lupus nephritis identified specific barriers to decisions related to medications. Information relevant to known/anticipated medication side effects and medication cost will form the basis of a patient guide for women with systemic lupus erythematosus, currently under development.

  1. The Impact of Star Formation Histories on Stellar Mass Estimation: Implications from the Local Group Dwarf Galaxies

    Science.gov (United States)

    Zhang, Hong-Xin; Puzia, Thomas H.; Weisz, Daniel R.

    2017-11-01

    Building on the relatively accurate star formation histories (SFHs) and metallicity evolution of 40 Local Group (LG) dwarf galaxies derived from resolved color-magnitude diagram modeling, we carried out a comprehensive study of the influence of SFHs, metallicity evolution, and dust extinction on the UV-to-near-IR color-mass-to-light ratio (color-{log}{{{\\Upsilon }}}\\star (λ)) distributions and M ⋆ estimation of local universe galaxies. We find that (1) the LG galaxies follow color-{log}{{{\\Upsilon }}}\\star (λ) relations that fall in between the ones calibrated by previous studies; (2) optical color-{log}{{{\\Upsilon }}}\\star (λ) relations at higher [M/H] are generally broader and steeper; (3) the SFH “concentration” does not significantly affect the color-{log}{{{\\Upsilon }}}\\star (λ) relations; (4) light-weighted ages }λ and metallicities }λ together constrain {log}{{{\\Upsilon }}}\\star (λ) with uncertainties ranging from ≲0.1 dex for the near-IR up to 0.2 dex for the optical passbands; (5) metallicity evolution induces significant uncertainties to the optical but not near-IR {{{\\Upsilon }}}\\star (λ) at a given }λ and }λ ; (6) the V band is the ideal luminance passband for estimating {{{\\Upsilon }}}\\star (λ) from single colors, because the combinations of {{{\\Upsilon }}}\\star (V) and optical colors such as B - V and g - r exhibit the weakest systematic dependences on SFHs, metallicities, and dust extinction; and (7) without any prior assumption on SFHs, M ⋆ is constrained with biases ≲0.3 dex by the optical-to-near-IR SED fitting. Optical passbands alone constrain M ⋆ with biases ≲0.4 dex (or ≲0.6 dex) when dust extinction is fixed (or variable) in SED fitting. SED fitting with monometallic SFH models tends to underestimate M ⋆ of real galaxies. M ⋆ tends to be overestimated (or underestimated) at the youngest (or oldest) }{mass}.

  2. The program of group constants creation (SMOK) on basis libraries of evaluated nuclear data in ENDE/B format for physical module FORTUN-88

    International Nuclear Information System (INIS)

    Borisov, A.A.

    1991-01-01

    The SMOK program for creation of group microconstants in the FORTUN-88 physical module format providing for calculations of neutron transport by the Monte Carlo method is described. The program processes files of evaluated neutron nuclear data in the ENDF-4 format. The constant structure gives an apportunity to simulate the process of neutron collisions with matter in details. The program service capabilities provide for graphical constant comparison. 11 refs

  3. Tracing the transport of colored dissolved organic matter in water masses of the Southern Beaufort Sea: relationship with hydrographic characteristics

    OpenAIRE

    Matsuoka, A.; Bricaud, A.; Benner, R.; Para, J.; Sempéré, R.; Prieur, L.; Bélanger, S.; Babin, M.

    2012-01-01

    Light absorption by colored dissolved organic matter (CDOM) [aCDOM(λ)] plays an important role in the heat budget of the Arctic Ocean, contributing to the recent decline in sea ice, as well as in biogeochemical processes. We investigated aCDOM(λ) in the Southern Beaufort Sea where a significant amount of CDOM is delivered by the Mackenzie River. In the surface layer, aCDOM(440) showed a strong and negat...

  4. Tracing the transport of colored dissolved organic matter in water masses of the Southern Beaufort Sea: relationship with hydrographic characteristics

    OpenAIRE

    A. Matsuoka; A. Bricaud; R. Benner; J. Para; R. Sempéré; L. Prieur; S. Bélanger; M. Babin

    2011-01-01

    Light absorption by colored dissolved organic matter (CDOM) (aCDOM(λ)) plays an important role in the heat budget of the Arctic Ocean, contributing to the recent decline in sea ice, as well as in biogeochemical processes. We investigated aCDOM(λ) in the Southern Beaufort Sea where a significant amount of CDOM is delivered by the Mackenzie River. In the surface layer, a

  5. Dissolved methane in the Beaufort Sea and the Arctic Ocean, 1992–2009; sources and atmospheric flux

    NARCIS (Netherlands)

    Lorenson, T.D.; Greinert, J.; Coffin, R.B.

    2016-01-01

    Methane concentration and isotopic composition was measured in ice-covered and ice-free waters of theArctic Ocean during 11 surveys spanning the years of 1992–1995 and 2009. During ice-free periods, methaneflux from the Beaufort shelf varies from 0.14 mg CH4 m22 d21 to 0.43 mg CH4 m22 d21. Maximum

  6. Trophic transfer of persistent organochlorine contaminants (OCs) within an Arctic marine food web from the southern Beaufort-Chukchi Seas

    International Nuclear Information System (INIS)

    Hoekstra, P.F.; O'Hara, T.M.; Fisk, A.T.; Borgaa, K.; Solomon, K.R.; Muir, D.C.G.

    2003-01-01

    The trophic status and biomagnification of persistent OCs within the near-shore Beaufort-Chukchi Seas food web from Barrow, AK is discussed. - Stable isotope values (δ 13 C, δ 15 N) and concentrations of persistent organochlorine contaminants (OCs) were determined to evaluate the near-shore marine trophic status of biota and biomagnification of OCs from the southern Beaufort-Chukchi Seas (1999-2000) near Barrow, AK. The biota examined included zooplankton (Calanus spp.), fish species such as arctic cod (Boreogadus saida), arctic char (Salvelinus alpinus), pink salmon (Oncorhynchus gorbuscha), and fourhorn sculpin (Myoxocephalus quadricornis), along with marine mammals, including bowhead whales (Balaena mysticetus), beluga whales (Delphinapterus leucas), ringed seals (Phoca hispida) and bearded seals (Erignathus barbatus). The isotopically derived trophic position of biota from the Beaufort-Chukchi Seas marine food web, avian fauna excluded, is similar to other coastal food webs in the Arctic. Concentrations of OCs in marine mammals were significantly greater than in fish and corresponded with determined trophic level. In general, OCs with the greatest food web magnification factors (FWMFs) were those either formed due to biotransformation (e.g. p,p'-DDE, oxychlordane) or considered recalcitrant (e.g. β-HCH, 2,4,5-Cl substituted PCBs) in most biota, whereas concentrations of OCs that are considered to be readily eliminated (e.g. γ-HCH) did not correlate with trophic level. Differences in physical-chemical properties of OCs, feeding strategy and possible biotransformation were reflected in the variable biomagnification between fish and marine mammals. The FWMFs in the Beaufort-Chukchi Seas region were consistent with reported values in the Canadian Arctic and temperate food webs, but were statistically different than FWMFs from the Barents and White Seas, indicating that the spatial variability of OC contamination in top-level marine Arctic predators is

  7. ENDF-6 formats manual. Version of June 1997. Written by the members of the US cross section evaluation working group

    International Nuclear Information System (INIS)

    McLane, V.; Dunford, C.L.; Rose, P.F.

    1997-01-01

    ENDF-6 is the international computer file format for evaluated nuclear data. This document gives a detailed description of the formats and procedures adopted for ENDF-6. It consists of the report BNL-NCS-44945 (Rev. 2/97) (=ENDF-201, Rev. 2/97) with an Interim Revision of June 1997 and a few front pages added by the IAEA Nuclear Data Section. (author)

  8. Group additivity values for enthalpies of formation (298 K), entropies (298 K), and molar heat capacities (300 K < T < 1500 K) of gaseous fluorocarbons

    International Nuclear Information System (INIS)

    Van Otterloo, Maren K.; Girshick, Steven L.; Roberts, Jeffrey T.

    2007-01-01

    A group additivity method was developed to estimate standard enthalpies of formation and standard entropies at 298 K of linear radical and closed-shell, gaseous fluorocarbon neutrals containing four or more carbon atoms. The method can also be used to estimate constant pressure molar heat capacities of the same compounds over the temperature range 300 K to 1500 K. Seventeen groups and seven fluorine-fluorine interaction terms were defined from 12 fluorocarbon molecules. Interaction term values from Yamada and Bozzelli [T. Yamada, J.W. Bozzelli, J. Phys. Chem. A 103 (1999) 7373-7379] were utilized. The enthalpy of formation group values were derived from G3MP2 calculations by Bauschlicher and Ricca [C.W. Bauschlicher, A. Ricca, J. Phys. Chem. A 104 (2000) 4581-4585]. Standard entropy and molar heat capacity group values were estimated from ab initio geometry optimization and frequency calculations at the Hartree-Fock level using the 6-31G(d) basis set. Enthalpies of formation for larger fluorocarbons estimated from the group additivity method compare well to enthalpies of formation found in the literature

  9. Testing Timescales for Rhythms Recorded in the 2.5 Ga Banded Iron Formation of the Dales Gorge Member (Brockman Iron Formation, Hamersley Group, Australia)

    Science.gov (United States)

    Hinnov, L. A.; de Oliveira Carvalho Rodrigues, P.; Franco, D.

    2017-12-01

    The classic, Superior-type banded iron formation (BIF) of the Precambrian Dales Gorge Member (DGM) of the Brockman Iron Formation, Hamersley Basin, Western Australia consists of a succession of micro- (millimeter-scale) and meso- (centimeter to decimeter-scale) bands of primarily iron-silica chemical sediment alternations, separated into macro- (meter to decameter-scale) bands by shales (1). Here, we present a time-frequency analysis of a gray-scale scan of the DGM "type section core" Hole 47A with small contributions from Hole EC10 (1) to provide a comprehensive characterization of banding patterns and periodicity throughout the 140 m section. SHRIMP zircon ages (2) indicate that the DGM was deposited over approximately 30 myr during the Archean-Proterozoic transition just prior to the Great Oxidation Event. This suggests that the banding patterns recorded Milankovitch cycles, although with orbital-rotational parameters significantly different from present-day due to Earth's tidal dissipation and chaotic episodes in the Solar System since 2.5 Ga. Banding patterns change systematically within the formation in response to slowly varying environmental conditions, which have been interpreted previously to be related to sea level change and basin evolution (3). Researchers, including (2), have questioned the 30 myr duration, suggesting instead that the micro-bands may be annual in scale. This would indicate a much shorter duration of less than 150 kyr for the DGM. In an attempt to determine whether Milankovitch cycles could have generated the meso-band patterns, we present detailed studies of BIF0 and BIF12, which typify the marked changes in meso-banding along the section. Objective procedures are also applied, including ASM (4) and TIMEOPT (5) to test for a range of potential alternative timescales assuming orbital-rotational parameter values modeled for 2.5 Ga. References: (1) Trendall, A.K., Blockley, J.G., GSWA Ann. Rep. 1967, 48, 1968; (2) Trendall, A.K., et al

  10. Unusual C-C bond cleavage in the formation of amine-bis(phenoxy) group 4 benzyl complexes: Mechanism of formation and application to stereospecific polymerization

    KAUST Repository

    Gowda, Ravikumar R.; Caporaso, Lucia; Cavallo, Luigi; Chen, Eugene You Xian

    2014-01-01

    Group 4 tetrabenzyl compounds MBn4 (M = Zr, Ti), upon protonolysis with an equimolar amount of the tetradentate amine-tris(phenol) ligand N[(2,4-tBu2C6H2(CH 2)OH]3 in toluene from -30 to 25 °C, unexpectedly lead to amine-bis(phenoxy) dibenzyl

  11. Ab initio computational study of –N-C and –O-C bonding formation : functional group modification reaction based chitosan

    Science.gov (United States)

    Siahaan, P.; Salimah, S. N. M.; Sipangkar, M. J.; Hudiyanti, D.; Djunaidi, M. C.; Laksitorini, M. D.

    2018-04-01

    Chitosan application in pharmaceutics and cosmeceutics industries is limited by its solubility issue. Modification of -NH2 and -OH fuctional groups of chitosan by adding carboxyl group has been shown to improve its solubility and application. Attempt to synthesize carboxymethyl chitosan (CMC) from monocloroacetic acid (MCAA) has been done prior this report. However no information is available wether –OH (-O-C bonding formation) or -NH2 (-N-C bonding formation) is the preference for - CH2COOH to attach. In the current study, the reaction mechanism between chitosan and MCAA reactants into carboxymethyl chitosan (CMC) was examined by computational approach. Dimer from of chitosan used as a molecular model in calculation All the molecular structure involved in the reaction mechanism was optimized by ab initio computational on the theory and basis set HF/6-31G(d,p). The results showed that the - N-C bonding formation via SN2 than the -O-C bonding formation via SN2 which have activation energy 469.437 kJ/mol and 533.219 kJ/mol respectively. However, the -O-C bonding formation more spontaneous than the -N-C bonding formation because ΔG the formation of O-CMC-2 reaction is more negative than ΔG of formation N-CMC-2 reaction is -4.353 kJ/mol and -1.095 kJ/mol respectively. The synthesis of N,O-CMC first forms -O-CH2COOH, then continues to form -NH-CH2COOH. This information is valuable to further optimize the reaction codition for CMC synthesis.

  12. Collaborative group and teacher formation: (transformation dialogues with a fledging university professor - doi: 10.4025/actascieduc.v35i2.20307

    Directory of Open Access Journals (Sweden)

    Maria Aparecida de Souza Perrelli

    2013-07-01

    Full Text Available Discussions on university teaching, teaching initiation and the necessary teacher support during the initial phase of their career are provided. The above mentioned discussions foregrounded a study by a research-formation collaborative Group. Sharing participants in the Group were involved in reflections on their professional practice to (transform themselves in the process. The text focused on a Group member, a fledging female professional in university teaching, and the support provided by co-trainers during this difficult phase in her career. Support comprised the provision of conditions for dialogues with the teacher, prompting her to understand the reasons that underlay their practice. Different strategies were used, esp the ‘formation letters’. The above contributed towards the production of an autobiographical narrative in which the professor reflected on her formation process as a professor. The reflective narratives on the teacher’s life, produced within the Group’s mediation and shared with its members, constituted important formation themes not merely for the teacher but also for those who interacted with her in the collaborative Group.

  13. Diols and anions can control the formation of an exciplex between a pyridinium boronic acid with an aryl group connected via a propylene linker.

    Science.gov (United States)

    Huang, Yan-Jun; Jiang, Yun-Bao; Bull, Steven D; Fossey, John S; James, Tony D

    2010-11-21

    The exciplex formation between a pyridinium boronic acid and phenyl group connected via a propylene linker can be monitored using fluorescence. Addition of pinacol affords a cyclic boronate ester with enhanced Lewis acidity that increases the strength of its cation-π stacking interaction causing a four-fold fluorescence enhancement.

  14. Qu'en est-il de la transmission dans les groupes d'analyse de pratiques en formation ?

    OpenAIRE

    Vallet, Patricia

    2012-01-01

    Atelier 21 : Travail social et bénévolat; Ma recherche s'intéresse à la formation des professionnels de la relation, et à cette instance particulière qu'est l'analyse des pratiques : celle-ci suppose la transmission d'une capacité de problématisation des situations professionnelles, un regard critique ajusté, un certain rapport aux savoirs, une attitude herméneutique, et une posture particulière de l'animateur pour favoriser le cheminement des personnes en formation. Car au-delà d'une meilleu...

  15. Polar bear population status in the northern Beaufort Sea, Canada, 1971-2006.

    Science.gov (United States)

    Stirling, Ian; McDonald, Trent L; Richardson, E S; Regehr, Eric V; Amstrup, Steven C

    2011-04-01

    Polar bears (Ursus maritimus) of the northern Beaufort Sea (NB) population occur on the perimeter of the polar basin adjacent to the northwestern islands of the Canadian Arctic Archipelago. Sea ice converges on the islands through most of the year. We used open-population capture-recapture models to estimate population size and vital rates of polar bears between 1971 and 2006 to: (1) assess relationships between survival, sex and age, and time period; (2) evaluate the long-term importance of sea ice quality and availability in relation to climate warming; and (3) note future management and conservation concerns. The highest-ranking models suggested that survival of polar bears varied by age class and with changes in the sea ice habitat. Model-averaged estimates of survival (which include harvest mortality) for senescent adults ranged from 0.37 to 0.62, from 0.22 to 0.68 for cubs of the year (COY) and yearlings, and from 0.77 to 0.92 for 2-4 year-olds and adults. Horvtiz-Thompson (HT) estimates of population size were not significantly different among the decades of our study. The population size estimated for the 2000s was 980 +/- 155 (mean and 95% CI). These estimates apply primarily to that segment of the NB population residing west and south of Banks Island. The NB polar bear population appears to have been stable or possibly increasing slightly during the period of our study. This suggests that ice conditions have remained suitable and similar for feeding in summer and fall during most years and that the traditional and legal Inuvialuit harvest has not exceeded sustainable levels. However, the amount of ice remaining in the study area at the end of summer, and the proportion that continues to lie over the biologically productive continental shelf (polar bear population in the northern Beaufort Sea will eventually decline. Management and conservation practices for polar bears in relation to both aboriginal harvesting and offshore industrial activity will need to

  16. Survival and breeding of polar bears in the southern Beaufort Sea in relation to sea ice

    Science.gov (United States)

    Regehr, E.V.; Hunter, C.M.; Caswell, H.; Amstrup, Steven C.; Stirling, I.

    2010-01-01

    1. Observed and predicted declines in Arctic sea ice have raised concerns about marine mammals. In May 2008, the US Fish and Wildlife Service listed polar bears (Ursus maritimus) - one of the most ice-dependent marine mammals - as threatened under the US Endangered Species Act. 2. We evaluated the effects of sea ice conditions on vital rates (survival and breeding probabilities) for polar bears in the southern Beaufort Sea. Although sea ice declines in this and other regions of the polar basin have been among the greatest in the Arctic, to date population-level effects of sea ice loss on polar bears have only been identified in western Hudson Bay, near the southern limit of the species' range. 3. We estimated vital rates using multistate capture-recapture models that classified individuals by sex, age and reproductive category. We used multimodel inference to evaluate a range of statistical models, all of which were structurally based on the polar bear life cycle. We estimated parameters by model averaging, and developed a parametric bootstrap procedure to quantify parameter uncertainty. 4. In the most supported models, polar bear survival declined with an increasing number of days per year that waters over the continental shelf were ice free. In 2001-2003, the ice-free period was relatively short (mean 101 days) and adult female survival was high (0 ∙ 96-0 ∙ 99, depending on reproductive state). In 2004 and 2005, the ice-free period was longer (mean 135 days) and adult female survival was low (0 ∙ 73-0 ∙ 79, depending on reproductive state). Breeding rates and cub litter survival also declined with increasing duration of the ice-free period. Confidence intervals on vital rate estimates were wide. 5. The effects of sea ice loss on polar bears in the southern Beaufort Sea may apply to polar bear populations in other portions of the polar basin that have similar sea ice dynamics and have experienced similar, or more severe, sea ice declines. Our findings

  17. Site-Specific Bluff Recession Rates Measured on the Alaskan Beaufort Sea Coast

    Science.gov (United States)

    Richmond, B.; Gadd, P.; Crowell, W.

    2017-12-01

    OverviewThe effects of climate change are being studied globally with coastal erosion in Arctic regions of particular concern. In support of Hilcorp Alaska's Northstar Development, short- and long-term bluff recession rates have been documented at a pipeline shore crossing located in Gwydyr Bay on the Alaskan Beaufort Sea coast. These data are presented, along with the predominant forcing mechanisms, and compared to local and regional recession rates recently published by the U.S. Geological Survey (USGS). Arctic Bluff RecessionCoastal retreat along the northern coast of Alaska occurs at two different rates: infrequent, but rapid erosion induced by strong westerly storms, and seasonal retreat related to thawing and sediment removal under more moderate wave conditions. Variability in the rate of bluff retreat is related to a number of factors, including bluff composition (ice content and sediment type), existence of a fronting beach, and wave exposure. Measured Bluff Recession at the Northstar Pipeline Shore CrossingThe location of the Northstar Development pipeline shore crossing was chosen based on analysis of historical aerial photos acquired between 1949 and 1996. Over this 47-year period, the average annualized rate of bluff retreat in the study area ranged from 1.6 to 3.0 ft/yr. Beginning in 1996, ground-based shoreline monitoring surveys have been conducted along the bluff and ten shore-perpendicular transects at the site. The rates of bluff retreat derived from the survey data have been modest, ranging from no change to 5.8 ft/yr. The monitoring surveys indicate that waves and currents erode the bluffs by direct impact only during infrequent, but strong westerly storms that promote a short-term rise in sea level (storm surge). The more prevalent easterly storms can cause set-down, or reduction in the sea level which limits direct wave impact on the bluff, thereby decreasing the potential for wave induced erosion. Comparative StudiesRecent studies conducted

  18. Polar bear population status in the northern Beaufort Sea, Canada, 1971-2006

    Science.gov (United States)

    Stirling, I.; McDonald, T.L.; Richardson, E.S.; Regehr, E.V.; Amstrup, Steven C.

    2011-01-01

    Polar bears (Ursus maritimus) of the northern Beaufort Sea (NB) population occur on the perimeter of the polar basin adjacent to the northwestern islands of the Canadian Arctic Archipelago. Sea ice converges on the islands through most of the year. We used open-population capture–recapture models to estimate population size and vital rates of polar bears between 1971 and 2006 to: (1) assess relationships between survival, sex and age, and time period; (2) evaluate the long-term importance of sea ice quality and availability in relation to climate warming; and (3) note future management and conservation concerns. The highest-ranking models suggested that survival of polar bears varied by age class and with changes in the sea ice habitat. Model-averaged estimates of survival (which include harvest mortality) for senescent adults ranged from 0.37 to 0.62, from 0.22 to 0.68 for cubs of the year (COY) and yearlings, and from 0.77 to 0.92 for 2–4 year-olds and adults. Horvtiz-Thompson (HT) estimates of population size were not significantly different among the decades of our study. The population size estimated for the 2000s was 980 ± 155 (mean and 95% CI). These estimates apply primarily to that segment of the NB population residing west and south of Banks Island. The NB polar bear population appears to have been stable or possibly increasing slightly during the period of our study. This suggests that ice conditions have remained suitable and similar for feeding in summer and fall during most years and that the traditional and legal Inuvialuit harvest has not exceeded sustainable levels. However, the amount of ice remaining in the study area at the end of summer, and the proportion that continues to lie over the biologically productive continental shelf (polar bear population in the northern Beaufort Sea will eventually decline. Management and conservation practices for polar bears in relation to both aboriginal harvesting and offshore industrial activity will need

  19. Survival and breeding of polar bears in the southern Beaufort Sea in relation to sea ice.

    Science.gov (United States)

    Regehr, Eric V; Hunter, Christine M; Caswell, Hal; Amstrup, Steven C; Stirling, Ian

    2010-01-01

    1. Observed and predicted declines in Arctic sea ice have raised concerns about marine mammals. In May 2008, the US Fish and Wildlife Service listed polar bears (Ursus maritimus) - one of the most ice-dependent marine mammals - as threatened under the US Endangered Species Act. 2. We evaluated the effects of sea ice conditions on vital rates (survival and breeding probabilities) for polar bears in the southern Beaufort Sea. Although sea ice declines in this and other regions of the polar basin have been among the greatest in the Arctic, to date population-level effects of sea ice loss on polar bears have only been identified in western Hudson Bay, near the southern limit of the species' range. 3. We estimated vital rates using multistate capture-recapture models that classified individuals by sex, age and reproductive category. We used multimodel inference to evaluate a range of statistical models, all of which were structurally based on the polar bear life cycle. We estimated parameters by model averaging, and developed a parametric bootstrap procedure to quantify parameter uncertainty. 4. In the most supported models, polar bear survival declined with an increasing number of days per year that waters over the continental shelf were ice free. In 2001-2003, the ice-free period was relatively short (mean 101 days) and adult female survival was high (0.96-0.99, depending on reproductive state). In 2004 and 2005, the ice-free period was longer (mean 135 days) and adult female survival was low (0.73-0.79, depending on reproductive state). Breeding rates and cub litter survival also declined with increasing duration of the ice-free period. Confidence intervals on vital rate estimates were wide. 5. The effects of sea ice loss on polar bears in the southern Beaufort Sea may apply to polar bear populations in other portions of the polar basin that have similar sea ice dynamics and have experienced similar, or more severe, sea ice declines. Our findings therefore are

  20. Formative Assessment: Using Concept Cartoon, Pupils' Drawings, and Group Discussions to Tackle Children's Ideas about Biological Inheritance

    Science.gov (United States)

    Chin, Christine; Teou, Lay-Yen

    2010-01-01

    This study was carried out in the context of formative assessment where assessment and learning were integrated to enhance both teaching and learning. The purpose of the study was to: (a) identify pupils' ideas about biological inheritance through the use of a concept cartoon, pupils' drawings and talk, and (b) devise scaffolding structures that…

  1. The Younger Age Limit of Metasedimentary Protolith Formation of the Lower Part of the Udokan Group Rocks (Aldan Shield)

    Science.gov (United States)

    Kotov, A. B.; Salnikova, E. B.; Kovach, V. P.; Velikoslavinskii, S. D.; Sklyarov, E. V.; Gladkochub, D. P.; Larin, A. M.; Tolmacheva, E. V.; Fedoseenko, A. M.; Plotkina, Yu. V.

    2018-04-01

    Biotite plagiogranite intruding sediments of the Kodar Sub-Group of the Udokan Group that have both undergone amphibolite grade alterations has been dated by the U-Pb ID TIMS technique using zircon to 2105 ± 6 Ma. This age estimate to a first approximation corresponds to the younger age limit of deposition of the siliciclastics in the lower section of the Udokan Group.

  2. Dynamics of the accumulation process of the Earth group of planets: Formation of the reverse rotation of Venus

    Science.gov (United States)

    Koslov, N. N.; Eneyev, T. M.

    1979-01-01

    A numerical simulation of the process of formation of the terrestrial planets is carried within the framework of a new theory for the accumulation of planetary and satellite systems. The numerical simulation permitted determining the parameters of the protoplanetary disk from which Mercury, Venus and the Earth were formed as result of the evolution. The acquisition of a slow retrograde rotation for Venus was discovered during the course of the investigation, whereas Mercury and the Earth acquired direct rotation about their axes. Deviations of the semimajor axes of these three planets as well as the masses of the Earth and Venus from the true values are small as a rule (l 10%). It is shown that during the accumulation of the terrestrial planets, there existed a profound relationship between the process of formation of the orbits and masses of the planet and the process of formation of their rotation about their axes. Estimates are presented for the radii of the initial effective bodies and the time of evolution for the terrestrial accumulation zone.

  3. Caisson structures in the Beaufort Sea 1982-1990 : characteristics, instrumentation and ice loads

    Energy Technology Data Exchange (ETDEWEB)

    Timco, G.W.; Johnston, M.E. [National Research Council of Canada, Ottawa, ON (Canada). Canadian Hydraulics Centre

    2002-11-01

    This report presents a comprehensive overview of the instrumentation, characteristics and measured ice loads on the caisson structures used for exploratory drilling in the Canadian Beaufort Sea during the 1970s and 1980s. The focus was placed on the Tarsiut Caissons, the Single Steel Drilling Caisson (SSDC), the Caisson Retained Island (CRI), and the Molikpaq. Details on the ice-load measuring instrumentation were provided for each of the drill sites featuring an ice-load measurement program. The results of global loads on the structures were presented as a Line Load (global load per width of the structure) and the Global Pressure (line load per ice thickness). The authors showed that global loads were a function of the ice macrostructure (level first-year sea ice, multi-year ice, first-year ridges, hummock fields, isolated floes). A general increase in the Line Load with increasing ice thickness was revealed through analysis. There was considerable scatter in the data, and the authors explained it by examining the failure mode of the ice during the interaction process. 36 refs., 4 tabs., 57 figs.

  4. Coastal environment of the Beaufort Sea from field data and ERTS-1 imagery, summer 1972

    Science.gov (United States)

    Reimnitz, E. (Principal Investigator); Barnes, P. W.

    1972-01-01

    The author has identified the following significant results. An extensive field program during the spring and summer in the coastal Beaufort Sea test site has been completed using a wide variety of sensing techniques. Reduction of field data and ERTS-1 image analysis have shown the coastal environment to be complexly influenced by unique processes, most of which involve or are related to sea ice. Active sedimentologic processes along the Arctic coast are set in motion by the melting, flooding, and eventual overflow of rivers onto the sea ice. It is now apparent that only minor amounts of sediment are transported offshore at this stage; however, scouring of the bottom is significant beneath the strudels (drain holes) which develop in the fast ice canopy in the region of overflow. Areal salinity and turbidity patterns together with ERTS-1 imagery confirm a consistent influx of colder, clearer, saltier water towards the coast just east of the Colville River. Strong (up to 3 knots) bidirectional but intermittent currents often manifest themselves in imagery and aerial photographs as wakes behind grounded ice. Ice movement vectors generated from repetitive images indicate that ice drift is closely associated with wind direction, especially in shallow bays, and displacements of 4-22 kilometers were noted in 24 hours.

  5. Limited contribution of ancient methane to surface waters of the U.S. Beaufort Sea shelf

    Science.gov (United States)

    Sparrow, Katy J.; Kessler, John D.; Southon, John R.; Garcia-Tigreros, Fenix; Schreiner, Kathryn M.; Ruppel, Carolyn D.; Miller, John B.; Lehman, Scott J.; Xu, Xiaomei

    2018-01-01

    In response to warming climate, methane can be released to Arctic Ocean sediment and waters from thawing subsea permafrost and decomposing methane hydrates. However, it is unknown whether methane derived from this sediment storehouse of frozen ancient carbon reaches the atmosphere. We quantified the fraction of methane derived from ancient sources in shelf waters of the U.S. Beaufort Sea, a region that has both permafrost and methane hydrates and is experiencing significant warming. Although the radiocarbon-methane analyses indicate that ancient carbon is being mobilized and emitted as methane into shelf bottom waters, surprisingly, we find that methane in surface waters is principally derived from modern-aged carbon. We report that at and beyond approximately the 30-m isobath, ancient sources that dominate in deep waters contribute, at most, 10 ± 3% of the surface water methane. These results suggest that even if there is a heightened liberation of ancient carbon–sourced methane as climate change proceeds, oceanic oxidation and dispersion processes can strongly limit its emission to the atmosphere.

  6. Aerial surveys of endangered whales in the Beaufort Sea, Fall 1989. Final report

    International Nuclear Information System (INIS)

    Treacy, S.D.

    1990-11-01

    The OCSLA Amendments of 1978 (43 U.S.C. 1802) established a policy for the management of oil and natural gas in the OCS and for protection of the marine and coastal environments. The amended OCSLA authorizes the Secretary of the Interior to conduct studies in areas or regions of sales to ascertain the environmental impacts on the marine and coastal environments of the outer Continental Shelf and the coastal areas which may be affected by oil and gas development (43 U.S.C. 1346). The report describes field activities and data analyses for aerial surveys of bowhead whales conducted between 1 September 1989 and 20 October 1989 in the Beaufort Sea, primarily between 140 W. and 154 W. longitudes south of 72 N. latitude. Ice cover during September and October 1989 was exceptionally light. A total of 215 bowhead whales, 104 belukha whales, 9 bearded seals, 84 ringed seals, and 32 unidentified pinnipeds were observed in 1989 during 98.70 hours of survey effort that included 38.10 hours on randomized transects. The last sighting of a bowhead whale made during the survey occurred in open water on 19 October 1989. No whales were sighted during a subsequent flight on 20 October 1989. Estimated median and mean water depths were shallower than for previous surveys (1982-1989). This is consistent with a trend for whales to be located in shallower water during years of generally light ice cover

  7. Size distribution of absorbing and fluorescing DOM in Beaufort Sea, Canada Basin

    Science.gov (United States)

    Gao, Zhiyuan; Guéguen, Céline

    2017-03-01

    The molecular weight (MW) of dissolved organic matter (DOM) is considered as an important factor affecting the bioavailability of organic matter and associated chemical species. Colored DOM (CDOM) MW distribution was determined, for the first time, in the Beaufort Sea (Canada Basin) by asymmetrical flow field-flow fractionation (AF4) coupled with online diode array ultra violet-visible photometer and offline fluorescence detectors. The apparent MW ranged from 1.07 to 1.45 kDa, congruent with previous studies using high performance size exclusion chromatography and tangential flow filtration. Interestingly, a minimum in MW was associated with the Pacific Summer Waters (PSW), while higher MW was associated with the Pacific Winter Waters (PWW). The Arctic Intermediate Waters (AIW) did not show any significant change in MW and fluorescence intensities distribution between stations, suggesting homogeneous DOM composition in deep waters. Three fluorescence components including two humic-like components and one protein-like component were PARAFAC-validated. With the increase of MW, protein-like fluorescence component became more dominant while the majority remained as marine/microbially derived humic-like components. Overall, it is concluded that water mass origin influenced DOM MW distribution in the Arctic Ocean.

  8. Notice of availability, final environmental impact statement, Beaufort Sea oil and gas development/Northstar Project

    International Nuclear Information System (INIS)

    1999-01-01

    BP Exploration (Alaska) Inc. (BPXA) is proposing to develop the Northstar Unit, located approximately 6 miles offshore of Point Storkensen in the Alaskan Beaufort Sea. BPXA's proposed action is a self-contained development/production facility located on a reconstructed gravel island in 39 feet of water. Also proposed is construction of two buried subsea pipelines between the island and shoreline to transport oil and gas. The pipelines would connect with onshore facilities and the Trans Alaska Pipeline System (TAPS). In response to BPXA's submittal of a permit application under Section 10 of the Rivers and Harbors Act, Section 404 of the Clean Water Act, and Section 103 of the Marine Protection Research and Sanctuaries Act, the US Army Corps of engineers, Alaska District (Corps) determined that issuance of a permit for BPXA's proposed project constituted a major federal action that may significantly affect the quality of the human environment pursuant to the National Environmental Policy Act (NEPA). In addition, the US Environmental Protection Agency (EPA), determined under provisions of the Clean Water Act and 40 CFR Part 6 Subpart F that permitting by the EPA for BPXA's proposed project also constituted a major federal action that my significantly affect the quality of the human environment. As a result, preparation of an Environmental Impact Statement (EIS) under NEPA was undertaken to identify and evaluate a range of reasonable alternatives and evaluate the potential effects the alternates, including BPXA's proposed project, may have on the human environment

  9. Exploring the Relevance of Single-Gender Group Formation: What We Learn from a Massive Open Online Course (MOOC)

    Science.gov (United States)

    Bayeck, Rebecca Yvonne; Hristova, Adelina; Jablokow, Kathryn W.; Bonafini, Fernanda

    2018-01-01

    This paper reports the results of an exploratory study on participants' perception of the importance of single-gender grouping in a massive open online course (MOOC) delivered through the Coursera platform. Findings reveal that female and male learners' perception of single-gender grouping differs. Female students more than males indicated less…

  10. Integrating the ACR Appropriateness Criteria Into the Radiology Clerkship: Comparison of Didactic Format and Group-Based Learning.

    Science.gov (United States)

    Stein, Marjorie W; Frank, Susan J; Roberts, Jeffrey H; Finkelstein, Malka; Heo, Moonseong

    2016-05-01

    The aim of this study was to determine whether group-based or didactic teaching is more effective to teach ACR Appropriateness Criteria to medical students. An identical pretest, posttest, and delayed multiple-choice test was used to evaluate the efficacy of the two teaching methods. Descriptive statistics comparing test scores were obtained. On the posttest, the didactic group gained 12.5 points (P didactic group gained 14.4 points (P didactic lectures, group-based learning is more enjoyable, time efficient, and equally efficacious. The choice of educational method can be individualized for each institution on the basis of group size, time constraints, and faculty availability. Copyright © 2016 American College of Radiology. Published by Elsevier Inc. All rights reserved.

  11. ANALYSIS OF THE IMPACT OF THE OPERATIONAL FORMATION TWO GROUP TRAINS ON THE INDIVIDUAL PERFORMANCE OF THE WORK

    Directory of Open Access Journals (Sweden)

    M. P. Bozhko

    2010-02-01

    Full Text Available The research of operative management by the organization of wagon flows in trains on a railway direction is executed. It is proved the expediency of introduction of a rational combination of formation of single-unit trains and two-unit trains with the purpose of acceleration of delivery of cargoes. The duration of planning period is offered as a condition for decision-making on determination of category of a separate train. The economic effect of introduction of operative management is obtained.

  12. Biogeochemical and micropaleontological study of black chert, Sete Lagoas Formation, Bambui Group (Late Proterozoic), Sao Gabriel (GO), Brazil

    International Nuclear Information System (INIS)

    Subacius, S.M.R.

    1985-01-01

    The biogeochemical study of amorphous and structured organic matter (OM) in two samples of thinly laminated black cherts (SG-1 and SG-2) from Sete Lagoas Formation, State of Goias, Brazil, is presented. The spectra analysis of infra-red, electron paramagnetic resonance and isotope ratio of C-12 and C-13 shown that: the amorphous OM consists of a soluble fraction (SF) and a insoluble fraction (Kerogen), which only the latter is syngenetic; the allochthonous SF comes from several sources, mainly from Phanerozoic sediments and soil contamination; the SG-1 and SG-2 Kerogens have δ 13 C values (-27.2 per mille and - 29.2 per mille respectively), which suggest OM photosynthetized and submitted to a mild thermal hystory; although the preserved microbiota is dominated by allochthonous elements (colonial fragments) and planktonic forms, both Kerogens were derived for the most part from photo-autotrophic benthonic communities, probably responsible for the lamination in the original carbonate rock, both SG-1 and SG-2 Kerogens exhibits O/C and H/C ratios comparable to Proterozoic humic Kerogens (type IV); the preserved microflora represents a microbial community of the chert-algae facies typical of the Middle and upper Proterozoic; and the occurence of rare acritarchs (Kildinella spp.) in the microflora is biostratigraphically significant in that it suggests a Late Riphean or Vendian age (950-570 m.y.) for the Sete Lagoas Formation. (Author) [pt

  13. Tectonique dans la région de la mer de Beaufort (Arctique canadien (résumé Tectonism in the Beaufort Sea - Region of Arctic Canada (Abstract

    Directory of Open Access Journals (Sweden)

    Mroszczak W. E.

    2006-10-01

    Full Text Available Le delta de la Mackenzie et la mer de Beaufort qui en sont encore au début de l'exploration, peuvent devenir une région pétrolière majeure dans les années 1980. Ce vaste bassin tertiaire est situé dans un environnement arctique ; il a demandé et nécessitera dans l'avenir de nouvelles technologies pour développer et produire les hydrocarbures si l'exploration est couronnée de succès. L'exploration pour l'huile et le gaz a été active dans cette région depuis 1965 bien que les facteurs climatiques et économiques aient eu tendance à freiner cette exploration, particulièrement en mer. L'auteur présente un bref historique des recherches comprenant les derniers résultats des sondage dans la mer de Beaufort forés par Dome Petroleum et ses partenaires. On discute aussi l'origine des structures en mer, en commentant les données sismiques. La structuration est considérée comme le résultat d'une sédimentation rapide de clastiques au Tertiaire dans un bassin dont le substratum serait formé d'une épaisse série d'argiles sous-compactées d'âge jurassique ou crétacé. The Mackenzie Delta and offshore Beaufort Sea Region which is at a very early stage of exploration, may become a major source of hydrocarbons in the 1980's This large Tertiary basin is situated in an Arctic environment and has required, and will require in the future, new technology to develop and produce hydrocarbons if exploration is successful. Exploration for oil and gas has been active in the area since 1965 with climatic and economic factors contributing ta a slow pace of exploration, particularly in the offshore area. A brief history of exploration with and update of the latest results of drilling in the Beaufort by Dome Petroleum and its partners is presented. Using seismic data, the genesis of structures found in the offshore area is discussed. These are believed to be the result of rapid Tertiary clastic deposition in a basin underlain by a thick section of

  14. Professional identity formation in the transition from medical school to working life: a qualitative study of group-coaching courses for junior doctors.

    Science.gov (United States)

    de Lasson, Lydia; Just, Eva; Stegeager, Nikolaj; Malling, Bente

    2016-06-24

    The transition from student to medical doctor is challenging and stressful to many junior doctors. To practice with confidence and professionalism the junior doctors have to develop a strong professional identity. Various suggestions on how to facilitate formation of professional identity have been offered including the possible positive effect of group-coaching courses. The purpose of this study was to explore how group-coaching might facilitate professional identity formation among junior doctors in the transition period. Group-coaching courses comprising three whole-day sessions and five 2 h sessions during a period of 4 months were offered to junior doctors in the first years after graduation. The purpose was to support the participants' professional development, ability to relate to patients, relatives and staff and career development. The coaches in this study had a background as health professionals combined with coaching educations. Data was obtained through observations, open-ended questionnaires and interviews. A generic thematic analysis was applied. Forty-five doctors participated in six coaching groups. The three main themes emerging in the sessions were: Adoption to medical culture, career planning, and work/life-balance. The junior doctors found the coaching intervention highly useful in order to cope with these challenges. Furthermore, the group was a forum where the junior doctors could share thoughts and feelings with colleagues without being afraid that this would endanger their professional career. Many found new ways to respond to everyday challenges mainly through a new awareness of patterns of thinking and feeling. The participants found that the group-coaching course supported their professional identity formation (thinking, feeling and acting as a doctor), adoption to medical culture, career planning and managing a healthy work/life-balance. Further studies in different contexts are recommended as well as studies using other methods to

  15. Four groups of new aromatic halogenated disinfection byproducts: effect of bromide concentration on their formation and speciation in chlorinated drinking water.

    Science.gov (United States)

    Pan, Yang; Zhang, Xiangru

    2013-02-05

    Bromide is naturally present in source waters worldwide. Chlorination of drinking water can generate a variety of chlorinated and brominated disinfection byproducts (DBPs). Although substantial efforts have been made to examine the effect of bromide concentration on the formation and speciation of halogenated DBPs, almost all previous studies have focused on trihalomethanes and haloacetic acids. Given that about 50% of total organic halogen formed in chlorination remains unknown, it is still unclear how bromide concentration affects the formation and speciation of the new/unknown halogenated DBPs. In this study, chlorinated drinking water samples with different bromide concentrations were prepared, and a novel approach-precursor ion scan using ultra performance liquid chromatography/electrospray ionization-triple quadrupole mass spectrometry-was adopted for the detection and identification of polar halogenated DBPs in these water samples. With this approach, 11 new putative aromatic halogenated DBPs were identified, and they were classified into four groups: dihalo-4-hydroxybenzaldehydes, dihalo-4-hydroxybenzoic acids, dihalo-salicylic acids, and trihalo-phenols. A mechanism for the formation of the four groups of new aromatic halogenated DBPs was proposed. It was found that increasing the bromide concentration shifted the entire polar halogenated DBPs as well as the four groups of new DBPs from being less brominated to being more brominated; these new aromatic halogenated DBPs might be important intermediate DBPs formed in drinking water chlorination. Moreover, the speciation of the four groups of new DBPs was modeled: the speciation patterns of the four groups of new DBPs well matched those determined from the model equations, and the reactivity differences between HOBr and HOCl in reactions forming the four groups of new DBPs were larger than those in reactions forming trihalomethanes and haloacetic acids.

  16. Use of Flood Seasonality in Pooling-Group Formation and Quantile Estimation: An Application in Great Britain

    Science.gov (United States)

    Formetta, Giuseppe; Bell, Victoria; Stewart, Elizabeth

    2018-02-01

    Regional flood frequency analysis is one of the most commonly applied methods for estimating extreme flood events at ungauged sites or locations with short measurement records. It is based on: (i) the definition of a homogeneous group (pooling-group) of catchments, and on (ii) the use of the pooling-group data to estimate flood quantiles. Although many methods to define a pooling-group (pooling schemes, PS) are based on catchment physiographic similarity measures, in the last decade methods based on flood seasonality similarity have been contemplated. In this paper, two seasonality-based PS are proposed and tested both in terms of the homogeneity of the pooling-groups they generate and in terms of the accuracy in estimating extreme flood events. The method has been applied in 420 catchments in Great Britain (considered as both gauged and ungauged) and compared against the current Flood Estimation Handbook (FEH) PS. Results for gauged sites show that, compared to the current PS, the seasonality-based PS performs better both in terms of homogeneity of the pooling-group and in terms of the accuracy of flood quantile estimates. For ungauged locations, a national-scale hydrological model has been used for the first time to quantify flood seasonality. Results show that in 75% of the tested locations the seasonality-based PS provides an improvement in the accuracy of the flood quantile estimates. The remaining 25% were located in highly urbanized, groundwater-dependent catchments. The promising results support the aspiration that large-scale hydrological models complement traditional methods for estimating design floods.

  17. Bioaccumulation of petroleum hydrocarbons in arctic amphipods in the oil development area of the Alaskan Beaufort Sea.

    Science.gov (United States)

    Neff, Jerry M; Durell, Gregory S

    2012-04-01

    An objective of a multiyear monitoring program, sponsored by the US Department of the Interior, Bureau of Ocean Energy Management was to examine temporal and spatial changes in chemical and biological characteristics of the Arctic marine environment resulting from offshore oil exploration and development activities in the development area of the Alaskan Beaufort Sea. To determine if petroleum hydrocarbons from offshore oil operations are entering the Beaufort Sea food web, we measured concentrations of hydrocarbons in tissues of amphipods, Anonyx nugax, sediments, Northstar crude oil, and coastal peat, collected between 1999 and 2006 throughout the development area. Mean concentrations of polycyclic aromatic hydrocarbons (PAH), saturated hydrocarbons (SHC), and sterane and triterpane petroleum biomarkers (StTr) were not significantly different in amphipods near the Northstar oil production facility, before and after it came on line in 2001, and in amphipods from elsewhere in the study area. Forensic analysis of the profiles (relative composition and concentrations) of the 3 hydrocarbon classes revealed that hydrocarbon compositions were different in amphipods, surface sediments where the amphipods were collected, Northstar crude oil, and peat from the deltas of 4 North Slope rivers. Amphipods and sediments contained a mixture of petrogenic, pyrogenic, and biogenic PAH. The SHC in amphipods were dominated by pristane derived from zooplankton, indicating that the SHC were primarily from the amphipod diet of zooplankton detritus. The petroleum biomarker StTr profiles did not resemble those in Northstar crude oil. The forensic analysis revealed that hydrocarbons in amphipod tissues were not from oil production at Northstar. Hydrocarbons in amphipod tissues were primarily from their diet and from river runoff and coastal erosion of natural diagenic and fossil terrestrial materials, including seep oils, kerogens, and peat. Offshore oil and gas exploration and development

  18. Dissolved methane in the Beaufort Sea and the Arctic Ocean, 1992-2009; sources and atmospheric flux

    Science.gov (United States)

    Lorenson, Thomas D.; Greinert, Jens; Coffin, Richard B.

    2016-01-01

    Methane concentration and isotopic composition was measured in ice-covered and ice-free waters of the Arctic Ocean during eleven surveys spanning the years of 1992-1995 and 2009. During ice-free periods, methane flux from the Beaufort shelf varies from 0.14 to 0.43 mg CH4 m-2 day-1. Maximum fluxes from localized areas of high methane concentration are up to 1.52 mg CH4 m-2 day-1. Seasonal buildup of methane under ice can produce short-term fluxes of methane from the Beaufort shelf that varies from 0.28 to 1.01 to mg CH4 m-2 day-1. Scaled-up estimates of minimum methane flux from the Beaufort Sea and pan-Arctic shelf for both ice-free and ice-covered periods range from 0.02 Tg CH4 yr-1 and 0.30 Tg CH4 yr-1 respectively to maximum fluxes of 0.18 Tg CH4 yr-1 and 2.2 Tg CH4 yr-1 respectively. A methane flux of 0.36 Tg CH4 yr-1from the deep Arctic Ocean was estimated using data from 1993-94. The flux can be as much as 2.35 Tg CH4 yr-1 estimated from maximum methane concentrations and wind speeds of 12 m/s, representing only 0.42% of the annual atmospheric methane budget of ~560 Tg CH4 yr-1. There were no significant changes in methane fluxes during the time period of this study. Microbial methane sources predominate with minor influxes from thermogenic methane offshore Prudhoe Bay and the Mackenzie River delta and may include methane from gas hydrate. Methane oxidation is locally important on the shelf and is a methane sink in the deep Arctic Ocean.

  19. Apparent optical properties of the Canadian Beaufort Sea – Part 1: Observational overview and water column relationships

    Directory of Open Access Journals (Sweden)

    D. Antoine

    2013-07-01

    Full Text Available A data set of radiometric measurements collected in the Beaufort Sea (Canadian Arctic in August 2009 (Malina project is analyzed in order to describe apparent optical properties (AOPs in this sea, which has been subject to dramatic environmental changes for several decades. The two properties derived from the measurements are the spectral diffuse attenuation coefficient for downward irradiance, Kd, and the spectral remote sensing reflectance, Rrs. The former controls light propagation in the upper water column. The latter determines how light is backscattered out of the water and becomes eventually observable from a satellite ocean color sensor. The data set includes offshore clear waters of the Beaufort Basin as well as highly turbid waters of the Mackenzie River plumes. In the clear waters, we show Kd values that are much larger in the ultraviolet and blue parts of the spectrum than what could be anticipated considering the chlorophyll concentration. A larger contribution of absorption by colored dissolved organic matter (CDOM is responsible for these high Kd values, as compared to other oligotrophic areas. In turbid waters, attenuation reaches extremely high values, driven by high loads of particulate materials and also by a large CDOM content. In these two extreme types of waters, current satellite chlorophyll algorithms fail. This questions the role of ocean color remote sensing in the Arctic when Rrs from only the blue and green bands are used. Therefore, other parts of the spectrum (e.g., the red should be explored if one aims at quantifying interannual changes in chlorophyll in the Arctic from space. The very peculiar AOPs in the Beaufort Sea also advocate for developing specific light propagation models when attempting to predict light availability for photosynthesis at depth.

  20. The elusive concept of 'internal objects' (1934-1943). Its role in the formation of the Klein Group.

    Science.gov (United States)

    Hinshelwood, R D

    1997-10-01

    The author traces a debate about the concept of 'internal objects' that took place between 1937 and 1943 at a time when a group of British analysts was forming around Melanie Klein. The debate is set within a complex of personal, group and organisational dynamics, which the paper makes a start on unravelling. The history of the British Psycho-Analytical Society at this time exemplifies Bion's notion of group schism. The events in the Society's history demonstrate defensive aspects of the interaction between the opposed groups, which support members against various anxieties. These include the stress of the work of analysis, but also in this instance the particular anxieties deriving from the collapse of psychoanalysis in Europe, the state of war of the country as a whole, and the death of Freud shortly after he came to London. This psychoanalytic anxiety/defence model clarifies some aspects of the debate about internal objects, and demonstrates the way in which these various anxieties and defences become organised around a scientific debate in a scientific society.

  1. Strong far-infrared cooling lines, peculiar CO kinematics, and possible star-formation suppression in Hickson compact group 57

    DEFF Research Database (Denmark)

    Alatalo, K.; Appleton, P. N.; Lisenfeld, U.

    2014-01-01

    We present [C II] and [O I] observations from Herschel and CO(1-0) maps from the Combined Array for Research in Millimeter Astronomy (CARMA) of the Hickson compact group HCG 57, focusing on the galaxies HCG 57a and HCG 57d. HCG 57a has been previously shown to contain enhanced quantities of warm ...

  2. Formation of hydroxyl groups and exchange with deuterium on NaHX and NaHY zeolites

    International Nuclear Information System (INIS)

    Kubelkova, L.; Novakova, J.

    1976-01-01

    Deammoniation and dehydroxylation of Na(NH 4 )X and Na(NH 4 )Y zeolites were compared. With the X type, both processes overlapped and proceeded more easily than with the Y type. Both H forms contained structural OH groups and hydroxyls denoted as SiOH, to which the 3740 cm -1 band in the IR spectrum was assigned. In addition, the NaHX zeolite contained OH groups characterized by the 3700 and 3600 cm -1 bands. Certain differences in the behaviour of NaHX and NaHY zeolites during deammoniation and dehydroxylation might be attributed to the presence of ''non-localizable'' H atoms. The active sites for the D 2 -OH exchange were probably formed during dehydroxylation. Hydrogen in SiOH groups was replaced by deuterium in both zeolite types more slowly than H atoms in other OH groups, which influenced the kinetic variations in the gaseous phase. The presence of water in the gaseous phase affected the kinetics and could distort the determination of the number of H atoms bound in the zeolites. (author)

  3. Identifying priorities to improve maternal and child nutrition among the Khmu ethnic group, Laos: a formative study.

    Science.gov (United States)

    de Sa, Joia; Bouttasing, Namthipkesone; Sampson, Louise; Perks, Carol; Osrin, David; Prost, Audrey

    2013-10-01

    Chronic malnutrition in children remains highly prevalent in Laos, particularly among ethnic minority groups. There is limited knowledge of specific nutrition practices among these groups. We explored nutritional status, cultural beliefs and practices of Laos' Khmu ethnic group to inform interventions for undernutrition as part of a Primary Health Care (PHC) project. Mixed methods were used. For background, we disaggregated anthropometric and behavioural indicators from Laos' Multiple Indicator Cluster Survey. We then conducted eight focus group discussions and 33 semi-structured interviews with Khmu villagers and health care workers, exploring beliefs and practices related to nutrition. The setting was two rural districts in Luang Prabang province, in one of which the PHC project had been established for 3 years. There was a higher prevalence of stunting in the Khmu than in other groups. Disaggregation showed nutrition behaviours were associated with ethnicity, including exclusive breastfeeding. Villagers described strong adherence to post-partum food restrictions for women, while little change was described in intake during pregnancy. Most children were breastfed, although early introduction of pre-lacteal foods was noted in the non-PHC district. There was widespread variation in introduction and diversity of complementary foods. Guidance came predominantly from the community, with some input from health care workers. Interventions to address undernutrition in Khmu communities should deliver clear, consistent messages on optimum nutrition behaviours. Emphasis should be placed on dietary diversity for pregnant and post-partum mothers, encouraging exclusive breastfeeding and timely, appropriate complementary feeding. The impact of wider governmental policies on food security needs to be further assessed. © 2012 John Wiley & Sons Ltd.

  4. Evaluation of four structural best management practices for highway runoff in Beaufort and Colleton Counties, South Carolina, 2005–2006

    Science.gov (United States)

    Conlon, Kevin J.; Journey, Celeste A.

    2008-01-01

    From 2005 to 2006, the U.S. Geological Survey worked cooperatively with the South Carolina Department of Transportation in Beaufort and Colleton Counties, South Carolina, to assess the performance of four different structural devices that served as best management practices (BMPs). These structural devices were installed to mitigate the effects of stormwater runoff on waterways near State roads. The South Carolina Department of Transportation is required to address the quality of stormwater runoff from State-maintained roadways as part of the National Pollutant Discharge Elimination System stormwater program mandated in the Clean Water Act.

  5. Fission-track ages of the Tokai Group and associate formations in the east coast areas of Ise Bay and their significance in geohistory

    International Nuclear Information System (INIS)

    Makinouchi, Takeshi; Danhara, Toru; Isoda, Kunitoshi.

    1983-01-01

    Fission-track ages of volcanic ash layers within the Tokai Group and associate formations in the east coast areas of Ise Bay are obtained by grain-by-grain method with which individual ages for the respective zircon grains are measured. They are as follows; 1) a volcanic ash layer in the Karayama Formation (tentative age: 1.9 +- 0.4 Ma). Among the zircon grains in this layer, essential ones occupy only 1 per cent, and the others are accidental. 2) Ohtani volcanic ash layer (4.3 +- 0.6 Ma). 3) Kosugaya volcanic ash layer (4.0 +- 0.5 Ma). 4) Kaminoma volcanic ash layer (5.3 +- 0.4 Ma). 5) A volcanic ash layer in the Toyoura Formation seems to be older than 10 Ma. 6) Zircon grains in the Kofu volcanic ash layer (Tokai Group) include two types of spontaneous namely track, clear and vague ones. The latter vague tracks are shorter and thiner, and seem to suffer thermal annealing. The ages obtained have clarified the following Points; a) The tentative age, 1.9 Ma, of the ''Karayama'' volcanic ash layer suggests the existence of unknown Plio-Pleistocene sediment in the Nagoya area. b) The sedimentary basin of Lake Tokai was formed in the latest Miocene, about 6.5 Ma. Generation of the basin coincides approximately with the stage of synchronous and abrupt change in sedimentation rate in sedimentary basins on the Pacific side of central and southern Japan. c) The Tokai Group in Chita (Tokoname Group) intercalates the Gilbert/Epoch 5 boundary in the paleomagnetic chronology in the middle horizon of the group. d) Average rate of sedimentation is about 1 m/10 4 yrs in the marginal areas of the basin, and 3-5 m/10 4 yrs in the central areas. (author)

  6. Photoproduction of ammonium in the southeastern Beaufort Sea and its biogeochemical implications

    Directory of Open Access Journals (Sweden)

    H. Xie

    2012-08-01

    Full Text Available Photochemistry of dissolved organic matter (DOM plays an important role in marine biogeochemical cycles, including the regeneration of inorganic nutrients. DOM photochemistry affects nitrogen cycling by converting bio-refractory dissolved organic nitrogen to labile inorganic nitrogen, mainly ammonium (NH4+. During the August 2009 Mackenzie Light and Carbon (MALINA Program, the absorbed photon-based efficiency spectra of NH4+ photoproduction (i.e. photoammonification were determined using water samples from the SE Beaufort Sea, including the Mackenzie River estuary, shelf, and Canada Basin. The photoammonification efficiency decreased with increasing wavelength across the ultraviolet and visible regimes and was higher in offshore waters than in shelf and estuarine waters. The efficiency was positively correlated with the molar nitrogen:carbon ratio of DOM and negatively correlated with the absorption coefficient of chromophoric DOM (CDOM. Combined with collateral measurements of CO2 and CO photoproduction, this study revealed a stoichiometry of DOM photochemistry with a CO2 : CO : NH4+ molar ratio of 165 : 11 : 1 in the estuary, 60 : 3 : 1 on the shelf, and 18 : 2 : 1 in the Canada Basin. The NH4+ efficiency spectra, along with solar photon fluxes, CDOM absorption coefficients and sea ice concentrations, were used to model the monthly surface and depth-integrated photoammonification rates in 2009. The summertime (June–August rates at the surface reached 6.6 nmol l−1 d−1 on the Mackenzie Shelf and 3.7 nmol l−1 d−1 further offshore; the depth-integrated rates were correspondingly 8.8 μmol m−2 d−1 and 11.3 μmol m−2 d−1. The offshore depth-integrated rate in August (8.0 μmol m−2 d−1 was comparable to the

  7. Some Like it Hot: Linking Diffuse X-Ray Luminosity, Baryonic Mass, and Star Formation Rate in Compact Groups of Galaxies

    Science.gov (United States)

    Desjardins, Tyler D.; Gallagher, Sarah C.; Hornschemeier, Ann E.; Mulchaey, John S.; Walker, Lisa May; Brandt, Willian N.; Charlton, Jane C.; Johnson, Kelsey E.; Tzanavaris, Panayiotis

    2014-01-01

    We present an analysis of the diffuse X-ray emission in 19 compact groups (CGs) of galaxies observed with Chandra. The hottest, most X-ray luminous CGs agree well with the galaxy cluster X-ray scaling relations in L(x-T) and (L(x-sigma), even in CGs where the hot gas is associated with only the brightest galaxy. Using Spitzer photometry, we compute stellar masses and classify Hickson CGs 19, 22, 40, and 42, and RSCGs 32, 44, and 86 as fossil groups using a new definition for fossil systems that includes a broader range of masses. We find that CGs with total stellar and Hi masses are great than or equal to 10(sup (11.3) solar mass are often X-ray luminous, while lower-mass CGs only sometimes exhibit faint, localized X-ray emission. Additionally, we compare the diffuse X-ray luminosity against both the total UV and 24 micron star formation rates of each CG and optical colors of the most massive galaxy in each of the CGs. The most X-ray luminous CGs have the lowest star formation rates, likely because there is no cold gas available for star formation, either because the majority of the baryons in these CGs are in stars or the X-ray halo, or due togas stripping from the galaxies in CGs with hot halos. Finally, the optical colors that trace recent star formation histories of the most massive group galaxies do not correlate with the X-ray luminosities of the CGs, indicating that perhaps the current state of the X-ray halos is independent of the recent history of stellar mass assembly in the most massive galaxies.

  8. Rapid detection of rRNA group I pseudomonads in contaminated metalworking fluids and biofilm formation by fluorescent in situ hybridization.

    Science.gov (United States)

    Saha, Ratul; Donofrio, Robert S; Goeres, Darla M; Bagley, Susan T

    2012-05-01

    Metalworking fluids (MWFs), used in different machining operations, are highly prone to microbial degradation. Microbial communities present in MWFs lead to biofilm formation in the MWF systems, which act as a continuous source of contamination. Species of rRNA group I Pseudomonas dominate in contaminated MWFs. However, their actual distribution is typically underestimated when using standard culturing techniques as most fail to grow on the commonly used Pseudomonas Isolation Agar. To overcome this, fluorescent in situ hybridization (FISH) was used to study their abundance along with biofilm formation by two species recovered from MWFs, Pseudomonas fluorescens MWF-1 and the newly described Pseudomonas oleovorans subsp. lubricantis. Based on 16S rRNA sequences, a unique fluorescent molecular probe (Pseudo120) was designed targeting a conserved signature sequence common to all rRNA group I Pseudomonas. The specificity of the probe was evaluated using hybridization experiments with whole cells of different Pseudomonas species. The probe's sensitivity was determined to be 10(3) cells/ml. It successfully detected and enumerated the abundance and distribution of Pseudomonas indicating levels between 3.2 (± 1.1) × 10(6) and 5.0 (± 2.3) × 10(6) cells/ml in four different industrial MWF samples collected from three different locations. Biofilm formation was visualized under stagnant conditions using high and low concentrations of cells for both P. fluorescens MWF-1 and P. oleovorans subsp. lubricantis stained with methylene blue and Pseudo120. On the basis of these observations, this molecular probe can be successfully be used in the management of MWF systems to monitor the levels and biofilm formation of rRNA group I pseudomonads.

  9. Inferred gas hydrate and permafrost stability history models linked to climate change in the Beaufort-Mackenzie Basin, Arctic Canada

    Directory of Open Access Journals (Sweden)

    J. Majorowicz

    2012-03-01

    Full Text Available Atmospheric methane from episodic gas hydrate (GH destabilization, the "clathrate gun" hypothesis, is proposed to affect past climates, possibly since the Phanerozoic began or earlier. In the terrestrial Beaufort-Mackenzie Basin (BMB, GHs occur commonly below thick ice-bearing permafrost (IBP, but they are rare within it. Two end-member GH models, where gas is either trapped conventionally (Case 1 or where it is trapped dynamically by GH formation (Case 2, were simulated using profile (1-D models and a 14 Myr ground surface temperature (GST history based on marine isotopic data, adjusted to the study setting, constrained by deep heat flow, sedimentary succession conductivity, and observed IBP and Type I GH contacts in Mallik wells. Models consider latent heat effects throughout the IBP and GH intervals. Case 1 GHs formed at ~0.9 km depth only ~1 Myr ago by in situ transformation of conventionally trapped natural gas. Case 2 GHs begin to form at ~290–300 m ~6 Myr ago in the absence of lithological migration barriers. During glacial intervals Case 2 GH layers expand both downward and upward as the permafrost grows downward through and intercalated with GHs. The distinctive model results suggest that most BMB GHs resemble Case 1 models, based on the observed distinct and separate occurrences of GHs and IBP and the lack of observed GH intercalations in IBP. Case 2 GHs formed >255 m, below a persistent ice-filled permafrost layer that is as effective a seal to upward methane migration as are Case 1 lithological seals. All models respond to GST variations, but in a delayed and muted manner such that GH layers continue to grow even as the GST begins to increase. The models show that the GH stability zone history is buffered strongly by IBP during the interglacials. Thick IBP and GHs could have persisted since ~1.0 Myr ago and ~4.0 Myr ago for Cases 1 and 2, respectively. Offshore BMB IBP and GHs formed terrestrially during Pleistocene sea level low

  10. Seasonal salinity, temperature and density data for the Canadian Beaufort Sea shelf, 1987

    Energy Technology Data Exchange (ETDEWEB)

    Hopky, G E; Chiperzak, D B; Lawrence, M J

    1988-01-01

    This report contains salinity, temperature and density (CTD) data collected in the waters of the Canadian Beaufort Sea Shelf during 1987. A major objective of such data collection is to identify and characterize estuarine and marine habitats of significance to the biological communities, primarily fish, with a view to provide background data for assessing the implications of hydrocarbon development and production on those habitats. Salinity and temperature profile data were measured using a Guildline Model 8870 probe deployed from the ice surface in March and May, and from a ship during July to September. Ice thickness and secchi depth were measured during periods of ice cover and open water, respectively. Salinity values for samples collected from bottle casts were measured with an Autosal Model 8400 salinometer. Density was calculated using salinity and temperature values. During the ice cover periods of March and May, CTD profiles were measured at five and nine stations, respectively. For the open water July to September period, CTD profiles were measured at 41 stations. One additional station was sampled using bottle casts. Replicate CTD profiling was conducted at a number of stations, on a seasonal basis. The maximum depths of profiles measured from the ice surface ranged from 3.1 to 23.5 dbar. Salinity and temperature measurements ranged from 0.00 to 31.70, and -1.74 to 0.02/sup 0/C, respectively. Maximum depths of profiles measured during the open water period ranged from 2.9 to 196.4 dbar. During this same period, profile measurements of salinity and temperature ranged from 0.08 to 33.94, and -1.62 to 16.51/sup 0/C, respectively. 4 refs., 60 figs., 57 tabs.

  11. Subsea ice-bearing permafrost on the U.S. Beaufort Margin: 2. Borehole constraints

    Science.gov (United States)

    Ruppel, Carolyn D.; Herman, Bruce M.; Brothers, Laura L.; Hart, Patrick E.

    2016-01-01

    Borehole logging data from legacy wells directly constrain the contemporary distribution of subsea permafrost in the sedimentary section at discrete locations on the U.S. Beaufort Margin and complement recent regional analyses of exploration seismic data to delineate the permafrost's offshore extent. Most usable borehole data were acquired on a ∼500 km stretch of the margin and within 30 km of the contemporary coastline from north of Lake Teshekpuk to nearly the U.S.-Canada border. Relying primarily on deep resistivity logs that should be largely unaffected by drilling fluids and hole conditions, the analysis reveals the persistence of several hundred vertical meters of ice-bonded permafrost in nearshore wells near Prudhoe Bay and Foggy Island Bay, with less permafrost detected to the east and west. Permafrost is inferred beneath many barrier islands and in some nearshore and lagoonal (back-barrier) wells. The analysis of borehole logs confirms the offshore pattern of ice-bearing subsea permafrost distribution determined based on regional seismic analyses and reveals that ice content generally diminishes with distance from the coastline. Lacking better well distribution, it is not possible to determine the absolute seaward extent of ice-bearing permafrost, nor the distribution of permafrost beneath the present-day continental shelf at the end of the Pleistocene. However, the recovery of gas hydrate from an outer shelf well (Belcher) and previous delineation of a log signature possibly indicating gas hydrate in an inner shelf well (Hammerhead 2) imply that permafrost may once have extended across much of the shelf offshore Camden Bay.

  12. Temporal complexity of southern Beaufort Sea polar bear diets during a period of increasing land use

    Science.gov (United States)

    McKinney, Melissa A.; Atwood, Todd C.; Iverson, Sara J.; Peacock, Elizabeth

    2017-01-01

    From 2000 to 2013, use of land as a seasonal habitat by polar bears (Ursus maritimus) of the southern Beaufort Sea (SB) subpopulation substantially increased. This onshore use has been linked to reduced spatial and temporal availability of sea ice, as well as to the availability of subsistence‐harvested bowhead whale (Balaena mysticetus) bone piles. Here, we evaluated the role of climate conditions on consumption of traditional ice‐associated prey relative to onshore bowhead whale bone piles. We determined seasonal and interannual trends in the diets of SB polar bears using fatty acid‐based analysis during this period of increasing land use. Diet estimates of 569 SB polar bears from 2004 to 2012 showed high seasonal fluctuations in the proportions of prey consumed. Higher proportions of bowhead whale, as well as ringed seal (Pusa hispida) and beluga whale (Delphinapterus leucas), were estimated to occur in the winter–spring diet, while higher proportions of bearded seal (Erignathus barbatus) were estimated for summer–fall diets. Trends in the annual mean proportions of individual prey items were not found in either period, except for significant declines in the proportion of beluga in spring‐sampled bears. Nonetheless, in years following a high winter Arctic oscillation index, proportions of ice‐associated ringed seal were lower in the winter–spring diets of adult females and juveniles. Proportions of bowhead increased in the winter–spring diets of adult males with the number of ice‐free days over the continental shelf. In one or both seasons, polar bears that were in better condition were estimated to have consumed less ringed seal and/or more bowhead whale than those in worse condition. Therefore, climate variation over this recent period appeared to influence the extent of onshore vs. on‐ice food use, which in turn, appeared to be linked to fluctuating condition of SB polar bears.

  13. THRESHOLD DETERMINATION FOR LOCAL INSTANTANEOUS SEA SURFACE HEIGHT DERIVATION WITH ICEBRIDGE DATA IN BEAUFORT SEA

    Directory of Open Access Journals (Sweden)

    C. Zhu

    2018-05-01

    Full Text Available The NASA Operation IceBridge (OIB mission is the largest program in the Earth’s polar remote sensing science observation project currently, initiated in 2009, which collects airborne remote sensing measurements to bridge the gap between NASA’s ICESat and the upcoming ICESat-2 mission. This paper develop an improved method that optimizing the selection method of Digital Mapping System (DMS image and using the optimal threshold obtained by experiments in Beaufort Sea to calculate the local instantaneous sea surface height in this area. The optimal threshold determined by comparing manual selection with the lowest (Airborne Topographic Mapper ATM L1B elevation threshold of 2 %, 1 %, 0.5 %, 0.2 %, 0.1 % and 0.05 % in A, B, C sections, the mean of mean difference are 0.166 m, 0.124 m, 0.083 m, 0.018 m, 0.002 m and −0.034 m. Our study shows the lowest L1B data of 0.1 % is the optimal threshold. The optimal threshold and manual selections are also used to calculate the instantaneous sea surface height over images with leads, we find that improved methods has closer agreement with those from L1B manual selections. For these images without leads, the local instantaneous sea surface height estimated by using the linear equations between distance and sea surface height calculated over images with leads.

  14. The sedimentology of uranium-bearing sandstones on the farm Riet Kuil 307, Beaufort West area

    International Nuclear Information System (INIS)

    Cole, D.I.

    1980-10-01

    The sedimentology of four sandstones was studied in outcrop and in the subsurface on the farm Riet Kuil 307, near Beaufort West. Only two of these sandstones are mineralised. These are four surface and two subsurface uranium anomalies and one surface uranium anomaly. The sedimentological study was made by means of 47 vertical profiles measured across and adjacent to the surface anomalies as well as 11 core-logs, which intersected the subsurface anomalies. The unmineralised sandstones are included in this study. A total of 19 sedimentary facies was recognised within the fluvial sandstone sequence according to the criteria of grain-size and sedimentary structure. Transitions between the facies were subjected to a Markov chain analysis in order to delineate Markov-dependent transitions. Uranium mineralisation is almost entirely confined to the coarser-grained sedimentary facies, which probably acted as suitable aquifers for the transport of uraniferous solutions prior to the precipitation of the uranium. Horizontally bedded sandstone facies comprises 60 per cent of the total cumulative thickness of mineralisation. The nature of the bedding of this facies may have provided a more effective permeability zone for the transport of uraniferous solutions. This facies contains an abundance of carbonaceous material which acted as an important indirect reductant for the precipitation of uranium from solution. The direct reductant was most probably H 2 S produced by enaerobic bacteria acting on this carbonaceous material shortly after deposition of the sediments. Carbonaceous material also occurs in the other mineralised facies and is considered to be the major control on the mineralisation in the uranium-bearing sandstones

  15. Child and Family-Focused Cognitive-Behavioral Therapy for Pediatric Bipolar Disorder: Pilot Study of Group Treatment Format

    Science.gov (United States)

    West, Amy E.; Jacobs, Rachel H.; Westerholm, Robert; Lee, Adabel; Carbray, Julie; Heidenreich, Jodi; Pavuluri, Mani N.

    2009-01-01

    Introduction: This study is a preliminary report of a group adaptation of child- and family-focused cognitive behavior therapy (CFF-CBT) for pediatric bipolar disorder (PBD). Methods: CFF-CBT group treatment was provided to twenty six families who had children with a diagnosis of PBD ranging between six- and twelve-years-old. Results: Results indicated that CFF-CBT was feasible and acceptable to families. CFF-CBT resulted in significant improvement in manic, but not depressive, symptoms and in children’s psychosocial functioning post-treatment. In addition, although not statistically significant, parents reported an increased ability to cope with their child’s illness. Results of this study suggest that group psychosocial treatment provided alongside pharmacotherapy may help attain remission of symptoms, as well as increase overall psychosocial coping and well-being in both children and parents. Conclusion: Future work must include a more rigorous test of CFF-CBT in a randomized controlled trial. PMID:19718425

  16. Views of parents, teachers and children on health promotion in kindergarten--first results from formative focus groups and observations.

    Science.gov (United States)

    Sansolios, Sanne; Mikkelsen, Bent Egberg

    2011-10-01

    The aim of the study was to capture the views of children, parents and teachers on the topic of physical activity in kindergarten through observation and focus group interviews. The study was conducted in the kindergartens from the sampling group in the Danish part of PERISCOPE. 1(st) methodology: Children interviewed inside by the researcher on preferable movements and settings and then observed outside during their playtime. 2(nd) methodology: Children asked to draw themselves playing their most preferred physical activity. Parents and kindergarten teachers interviewed in two different groups, using an identical guide. Children are skilled in taking advantage of the space and facilities available for physical activity; girls need more support than boys to initiate physical activity; children are happy with the facilities and the toys available in the kindergarten. Teachers feel an increasing pressure to take more responsibility and initiatives for the children's health habits. Parents state that if more physical activity is initiated in the kindergarten, it could make children request domestic activity. Physical activity and movement concept are too abstract for children of this age to talk about: they quickly lose their focus and concentration. The new methodology of videotaping gives the researcher the chance to interpret facial expressions to capture movement, talk and actions, and to make a distinction among children, as they tend to interrupt each other. However, this method contains a weakness, if used alone, by the fact that the shooting is only a reflection of what the video camera has recorded.

  17. Population genomic analysis of strain variation in Leptospirillum group II bacteria involved in acid mine drainage formation.

    Science.gov (United States)

    Simmons, Sheri L; Dibartolo, Genevieve; Denef, Vincent J; Goltsman, Daniela S Aliaga; Thelen, Michael P; Banfield, Jillian F

    2008-07-22

    Deeply sampled community genomic (metagenomic) datasets enable comprehensive analysis of heterogeneity in natural microbial populations. In this study, we used sequence data obtained from the dominant member of a low-diversity natural chemoautotrophic microbial community to determine how coexisting closely related individuals differ from each other in terms of gene sequence and gene content, and to uncover evidence of evolutionary processes that occur over short timescales. DNA sequence obtained from an acid mine drainage biofilm was reconstructed, taking into account the effects of strain variation, to generate a nearly complete genome tiling path for a Leptospirillum group II species closely related to L. ferriphilum (sampling depth approximately 20x). The population is dominated by one sequence type, yet we detected evidence for relatively abundant variants (>99.5% sequence identity to the dominant type) at multiple loci, and a few rare variants. Blocks of other Leptospirillum group II types ( approximately 94% sequence identity) have recombined into one or more variants. Variant blocks of both types are more numerous near the origin of replication. Heterogeneity in genetic potential within the population arises from localized variation in gene content, typically focused in integrated plasmid/phage-like regions. Some laterally transferred gene blocks encode physiologically important genes, including quorum-sensing genes of the LuxIR system. Overall, results suggest inter- and intrapopulation genetic exchange involving distinct parental genome types and implicate gain and loss of phage and plasmid genes in recent evolution of this Leptospirillum group II population. Population genetic analyses of single nucleotide polymorphisms indicate variation between closely related strains is not maintained by positive selection, suggesting that these regions do not represent adaptive differences between strains. Thus, the most likely explanation for the observed patterns of

  18. Population genomic analysis of strain variation in Leptospirillum group II bacteria involved in acid mine drainage formation.

    Directory of Open Access Journals (Sweden)

    Sheri L Simmons

    2008-07-01

    Full Text Available Deeply sampled community genomic (metagenomic datasets enable comprehensive analysis of heterogeneity in natural microbial populations. In this study, we used sequence data obtained from the dominant member of a low-diversity natural chemoautotrophic microbial community to determine how coexisting closely related individuals differ from each other in terms of gene sequence and gene content, and to uncover evidence of evolutionary processes that occur over short timescales. DNA sequence obtained from an acid mine drainage biofilm was reconstructed, taking into account the effects of strain variation, to generate a nearly complete genome tiling path for a Leptospirillum group II species closely related to L. ferriphilum (sampling depth approximately 20x. The population is dominated by one sequence type, yet we detected evidence for relatively abundant variants (>99.5% sequence identity to the dominant type at multiple loci, and a few rare variants. Blocks of other Leptospirillum group II types ( approximately 94% sequence identity have recombined into one or more variants. Variant blocks of both types are more numerous near the origin of replication. Heterogeneity in genetic potential within the population arises from localized variation in gene content, typically focused in integrated plasmid/phage-like regions. Some laterally transferred gene blocks encode physiologically important genes, including quorum-sensing genes of the LuxIR system. Overall, results suggest inter- and intrapopulation genetic exchange involving distinct parental genome types and implicate gain and loss of phage and plasmid genes in recent evolution of this Leptospirillum group II population. Population genetic analyses of single nucleotide polymorphisms indicate variation between closely related strains is not maintained by positive selection, suggesting that these regions do not represent adaptive differences between strains. Thus, the most likely explanation for the

  19. Characterization of Coal Quality Based On Ash Content From M2 Coal-Seam Group, Muara Enim Formation, South Sumatra Basin

    Directory of Open Access Journals (Sweden)

    Frillia Putri Nasution

    2017-09-01

    Full Text Available Muara Enim Formation is well known as coal-bearing formation in South Sumatra Basin. As coal-bearing formation, this formation was subjects of many integrated study. Muara Enim Formation can be divided into four coal-seam group, M1, M2, M3, and M4. The M2 group comprising of Petai (C, Suban (B, Lower Mangus (A2, and Upper Mangus (A1. Depositional environments of Group M2 is transitional lower delta plain with sub-depositional are crevasse splay and distributary channel. The differentiation of both sub-depositional environments can be caused the quality of coal deposit. One of quality aspects is ash content. This research conducted hopefully can give better understanding of relationship between depositional environments to ash content. Group M2 on research area were found only Seam C, Seam B, and Seam A2, that has distribution from north to central so long as 1400 m. Coal-seam thickness C ranged between 3.25-9.25 m, Seam B range 7.54-13.43 m, and Seam C range 1.53-8.37 m, where all of coal-seams thickening on the central part and thinning-splitting to northern part and southern part. The ash content is formed from burning coal residue material. Ash contents on coal seam caused by organic and inorganic compound which resulted from mixing modified material on surrounded when transportation, sedimentation, and coalification process. There are 27 sample, consists of 9 sample from Seam C, 8 sample from Seam B, and 10 sample from Seam A2. Space grid of sampling is 100-150 m. Ash content influenced by many factors, but in research area, main factor is existence of inorganic parting. Average ash content of Seam C is 6,04%, Seam B is 5,05%, and Seam A2 is 3,8%. Low ash content influenced by settle environment with minor detrital material. High ash content caused by oxidation and erosional process when coalification process. Ash content on coal in research area originated from detritus material carried by channel system into brackish area or originated

  20. Cult and society in early Athens : Archaeological and anthropological approaches to state formation and group participation in Attica

    OpenAIRE

    van den Eijnde, F.

    2010-01-01

    This doctoral thesis addresses the question of early Athenian statehood from the vantage point of the cultic remains. One of the main tenets of this book is that the principle stage for Athenian self-representation in the Classical Period, the cult of Athena on the Acropolis, was neither the only nor the first rallying point for the inhabitants of Attica in the Early Iron Age. It is argued that the Athenaioi (the “Men of Athena”) originated as an elite group, whose franchise did not extend be...

  1. Invertebrate ichnofossils and rhizoliths associated with rhizomorphs from the Marília Formation (Echaporã Member), Bauru Group, Upper Cretaceous, Brazil

    Science.gov (United States)

    Mineiro, Adriano Santos; Santucci, Rodrigo Miloni; da Rocha, Dulce Maria Sucena; de Andrade, Marco Brandalise; Nava, William Roberto

    2017-12-01

    The Marília Formation (Bauru Group, Upper Cretaceous, Brazil) has furnished a large array of vertebrate fossils. However, its ichnological and botanical contents are poorly explored to date. Here we report findings of invertebrate trace fossils (Beaconites isp., Skolithos isp., and Taenidium barretti), rhizoliths associated with rhizomorphs with preserved hyphae, and fossil roots from the Echaporã Member, Marília Formation, São Paulo State, Brazil. The association of trace fossils suggest they can be regarded to the Scoyenia Ichnofacies. The rhizoliths indicate that at least two types of herbaceous/arbustive plants inhabited the area, one of them living in the vadose zone and the other one with roots closer to the water table, under arid/semiarid conditions. Sedimentological analyses suggest the studied outcrop comprises fluvial deposits, with predominance of sand bars that underwent different and relatively long periods of subaerial exposure.

  2. Studying with the cloud: the use of online Web-based resources to augment a traditional study group format.

    Science.gov (United States)

    Chan, Teresa; Sennik, Serena; Zaki, Amna; Trotter, Brendon

    2015-03-01

    Cloud-based applications such as Google Docs, Skype, Dropbox, and SugarSync are revolutionizing the way that we interact with the world. Members of the millennial generation (those born after 1980) are now becoming senior residents and junior attending physicians. We describe a novel technique combining Internet- and cloud-based methods to digitally augment the classic study group used by final-year residents studying for the Royal College of Physicians and Surgeons of Canada examination. This material was developed by residents and improved over the course of 18 months. This is an innovation report about a process for enhanced communication and collaboration as there has been little research to date regarding the augmentation of learner-driven initiatives with virtual resources.

  3. [The difficult concept of "internal objects" (1934-1943). Its significance for the formation of the Klein group].

    Science.gov (United States)

    Hinshelwood, R D

    1996-06-01

    Although the concept of "inner objects" developed by Melanie Klein is hardly a major object of discussion today, it caused a furore in the ranks of the British Psychoanalytical Society in the thirties and forties. Notably the analysts from Vienna were unable to agree to the existence of inner objects engendered via processes of internalisation. The author traces the course of these discussions of a clinical problem and the confusion they caused, placing them at the same time in a specific historical context. He sees the controversy as the expression of conflicts and fears unsettling the British Psychoanalytical Society during that period, caused on the one hand by the necessary integration of the exiled Freud family and on the other by tensions within its own ranks leading ultimately to a division of the Society and the constitution of the Klein Group.

  4. Usefulness of postoperative hip irradiation in the prevention of heterotopic bone formation in a high risk group of patients

    International Nuclear Information System (INIS)

    MacLennan, I.; Keys, H.M.; Evarts, C.M.; Rubin, P.

    1984-01-01

    Heterotopic ossification is a complication of total hip arthroplasty in 14 to 30% of patients. Significant functional impairment will occur in up to 28% of patients with ectopic bone. The high risk group includes those with preexisting heterotopic bone in either hip, those suffering from hypertrophic osteoarthritis or ankylosing spondylitis and patients who have had multiple procedures on the hip. Fifty-eight patients (67 hips) were irradiated after surgical removal of ectopic bone (53 hips) or received radiation prophylaxis of heterotopic ossification (14 hips). Ninety-five percent of patients had either no bone visible or insignificant amounts of ectopic bone visible on postoperative hip X-rays. Only 5% of patients showed significant persistence of ectopic bone. Postoperative hip function was dramatically improved compared to preoperative function in all patients treated. The importance of early commencement of irradiation is emphasized

  5. Ambiência e formação de grupo em programas de caminhada Ambiance and group formation in walking programs

    Directory of Open Access Journals (Sweden)

    Marcos Warschauer

    2009-06-01

    Full Text Available O presente relato discute os conceitos de ambiência e formação de grupo por intermédio de duas experiências com grupos de caminhada desenvolvidos na Atenção Básica: o programa "Caminhando para a Saúde", em Santo André (SP, e o grupo da Unidade de Saúde Jardim Seckler, em São Paulo (SP. Ambas as experiências trabalham com a concepção de prática corporal, que amplia o conceito de atividade física ao colocar o sujeito no centro das ações, e têm como principal enfoque a promoção da saúde. A análise do processo de implementação desses programas destaca a ambiência e a formação de grupo como fatores fundamentais para a adesão à prática. O conceito de ambiência é composto de três eixos: a confortabilidade, o espaço como forma de produção de subjetividade e como instrumento facilitador de mudanças no processo de trabalho. Os dispositivos grupais promovem ações de cidadania, priorizando a solidariedade, a comunicação e os relacionamentos pessoais. Esses dois conceitos podem estar correlacionados e viabilizar outras maneiras para a implementação e o desenvolvimento de grupos de caminhada.The present report discusses the concepts of ambiance and group formation by means of two experiences with walking groups developed in Primary Care: the program "Walking for Health", in the city of Santo André, state of São Paulo, and the group of the Jardim Seckler Health Unit, in the city of São Paulo, state of São Paulo. Both experiences were developed using the body practice concept, which goes beyond the concept of physical activity, placing the person at the center of his/her own actions. The experiences' main focus is health promotion. Ambiance and group formation are fundamental factors to adhere to the walking practice. The ambiance concept is formed by three axes: comfortability, space as a way to produce subjectivity and as an instrument that facilitates change in the work process. Group activities promote

  6. Catalogue of polar bear (Ursus maritimus) maternal den locations in the Beaufort Sea and neighboring regions, Alaska, 1910-2010

    Science.gov (United States)

    Durner, George M.; Fischbach, Anthony S.; Amstrup, Steven C.; Douglas, David C.

    2010-01-01

    This report presents data on the approximate locations and methods of discovery of 392 polar bear (Ursus maritimus) maternal dens found in the Beaufort Sea and neighboring regions between 1910 and 2010 that are archived by the U.S. Geological Survey, Alaska Science Center, Anchorage, Alaska. A description of data collection methods, biases associated with collection method, primary time periods, and spatial resolution are provided. Polar bears in the Beaufort Sea and nearby regions den on both the sea ice and on land. Standardized VHF surveys and satellite radio telemetry data provide a general understanding of where polar bears have denned in this region over the past 3 decades. Den observations made during other research activities and anecdotal reports from other government agencies, coastal residents, and industry personnel also are reported. Data on past polar bear maternal den locations are provided to inform the public and to provide information for natural resource agencies in planning activities to avoid or minimize interference with polar bear maternity dens.

  7. Associations between physical activity, sedentary behavior, and glycemic control in a large cohort of adolescents with type 1 diabetes : the Hvidoere Study Group on Childhood Diabetes

    NARCIS (Netherlands)

    Aman, J.; Skinner, T. C.; de Beaufort, C. E.; Swift, P. G. F.; Aanstoot, H-J; Cameron, F.

    angstrom man J, Skinner TC, de Beaufort CE, Swift PGF, Aanstoot H-J, Cameron F, for and on behalf of the Hvidoere Study Group on Childhood Diabetes. Associations between physical activity, sedentary behavior, and glycemic control in a large cohort of adolescents with type 1 diabetes: the Hvidoere

  8. Examples of Savannah River water dilution between the Savannah River Plant and the Beaufort-Jasper and Port Wentworth water-treatment plants

    International Nuclear Information System (INIS)

    Hayes, D.W.

    1983-01-01

    A substantial dilution of the river water occurs between the Savannah River Plant (SRP) and the two treatment plants. This dilution results from inflow of surface and groundwater and from direct rainfall. The amount of dilution was estimated to be approximately 20% and 54% down to the Port Wentworth and Beaufort-Jasper plants, respectively

  9. Comparative palynology of clastics and lignites from the Manning Formation, Jackson Group, Upper Eocene, Grimes County, TX

    Energy Technology Data Exchange (ETDEWEB)

    Gennett, J.A. [Texas A& M Univ., College Station, TX (United States)

    1996-09-01

    The 3500 lignite seam at the Gibbons Creek Mine in Grimes County, TX was sampled for pollen and spores at 10 cm intervals. The majority of samples are dominated (to 60%) by Momipites from the Juglandaceae (walnut family), as is typical of Jackson Group sediments. Other palynomorph taxa vary systematically, with a peak of pollen of the freshwater tree Nyssa (blackgum) and associated Rboipites angustus (to 17%) occurring at the base. Higher in the seam, increase (to 55%) of Cupuliferoipollenites (a chestnut-like grain) and Cyrillaceae-pollenites? ventosus (to 7%) percentages may indicate a higher salinity environment. A Chrysophyllum (satin leaf) peak (to 25%) near the top of the seam suggests relatively shallow fresh-water conditions. Core samples from an interval above the lignites represent a transgressive-regressive cycle in inner shelf clastics. These samples were taken at 40 cm or greater intervals and reveal the regional pollen flora. Although minor changes occur, palynomorph spectra are for the most part homogenous. The dominant grain is again Momipites coryloides, but in general percentages are lower (to 35%). Cupuliferoipollenites (to 17%), Chrysophyllum (to 5%), and Rhoipites angustus (to 3%) are not less important, but do not peak as they do in the lignite spectra. Palm leaf megafossils; in one sample suggest a clastic wetland; in this sample palm pollen (mostly Arecipites, representing the modern saw palmetto) reaches 73%. Another sample contains high (26%) percentages of the fern spore Lygodiumsporites adriennis. High percentages of these two taxa do not occur in the lignite samples.

  10. Gas hydrate formation and dissipation histories in the northern margin of Canada: Beaufort-Mackenzie and the Sverdrup Basins

    Czech Academy of Sciences Publication Activity Database

    Majorowicz, J.; Osadetz, K.; Šafanda, Jan

    2012-01-01

    Roč. 2012, č. 1 (2012), 879393/1-879393/17 ISSN 1687-8833 Institutional research plan: CEZ:AV0Z30120515 Keywords : gas hydrates * Canadian Arctic continental margin * permafrost Subject RIV: DC - Siesmology, Volcanology, Earth Structure

  11. Generation of seven group cross section library for TRIGA LEU fuel in CITATION format and benchmarking some experimental and operational data

    International Nuclear Information System (INIS)

    Sarker, M.M.; Bhuiyan, S.I.; Akramuzzaman, M.

    2007-01-01

    The principal objective of this study is to validate the seven group cross section library in CITATION format for TRIGA LEU Fuel. This presentation deals with the 'generation of a cross section library for the CITATION and its validation. We used WIMSD-5B version for the generation of all group constants. The overall strategy is: (1) use WIMS package to generate few group neutron macroscopic cross section (cell constants) for all of the materials in the core and its immediate neighborhood (2) use 3-D code CITATION to perform the global analysis of the core to study: multiplication factor, neutron flux distribution and power peaking factors. Various options available in WIMS program were studied in depth to finalize the models to generate the most appropriate group constants. For the global analysis the code CITATION and a post processing program FCAP were chosen. Thus a seven group cross section library for the calculations of TRIGA Research Reactor was generated. To investigate the validity of the generated library a critical experiment of the TRIGA research reactor was benchmarked. (author)

  12. The group A streptococcal collagen-like protein 1, Scl1, mediates biofilm formation by targeting the EDA-containing variant of cellular fibronectin expressed in wounded tissue

    Science.gov (United States)

    Oliver-Kozup, Heaven; Martin, Karen H.; Schwegler-Berry, Diane; Green, Brett J.; Betts, Courtney; Shinde, Arti V.; Van De Water, Livingston; Lukomski, Slawomir

    2012-01-01

    Summary Wounds are known to serve as portals of entry for group A Streptococcus (GAS). Subsequent tissue colonization is mediated by interactions between GAS surface proteins and host extracellular matrix components. We recently reported that the streptococcal collagen-like protein-1, Scl1, selectively binds the cellular form of fibronectin (cFn) and also contributes to GAS biofilm formation on abiotic surfaces. One structural feature of cFn, which is predominantly expressed in response to tissue injury, is the presence of a spliced variant containing extra domain A (EDA/EIIIA). We now report that GAS biofilm formation is mediated by the Scl1 interaction with EDA-containing cFn. Recombinant Scl1 proteins that bound cFn also bound recombinant EDA within the C-C′ loop region recognized by the α9β1 integrin. The extracellular 2-D matrix derived from human dermal fibroblasts supports GAS adherence and biofilm formation. Altogether, this work identifies and characterizes a novel molecular mechanism by which GAS utilizes Scl1 to specifically target an extracellular matrix component that is predominantly expressed at the site of injury in order to secure host tissue colonization. PMID:23217101

  13. Ecosystem model of the entire Beaufort Sea marine ecosystem: a tool for assessing food-web structure and ecosystem changes from 1970 to 2014

    Science.gov (United States)

    Suprenand, P. M.; Hoover, C.

    2016-02-01

    The Beaufort Sea coastal-marine ecosystem is approximately a 476,000 km2 area in the Arctic Ocean, which extends from -112.5 to -158° longitude to 67.5 to 75° latitude. Within this Arctic Ocean area the United States (Alaskan) indigenous communities of Barrow, Kaktovik, and Nuiqsut, and the Canadian (Northwest Territories) indigenous communities of Aklavik, Inuvik, Tuktoyaktuk, Paulatuk, Ulukhaktok, and Sachs Harbour, subsist by harvesting marine mammals, fish, and invertebrates from the Beaufort Sea to provide the majority of their community foods annually. The ecosystem in which the indigenous communities harvest is considered a polar habitat that includes many specialized species, such as polar bears that rely on sea-ice for foraging activities and denning, or ice algae that are attached to the cryosphere. However, the polar habitat has been experiencing a diminishing sea-ice extent, age, and seasonal duration, with concomitant increases in sea surface temperatures (SSTs), since the 1970s. Changes in sea-ice and SST have consequences to the Beaufort Sea coastal-marine ecosystem, which includes animal habitat losses, alterations to trophodynamics, and impacts to subsistence community harvesting. The present study was aimed at capturing trophodynamic changes in the Beaufort Sea coastal-marine ecosystem from 1970 to 2014 using a fitted spatial-temporal model (Ecopath with Ecosim and Ecospace) that utilizes forcing and mediation functions to describe animal/trophodynamic relationships with sea-ice and sea surface temperature, as well as individual community harvesting efforts. Model outputs reveals similar trends in animals population changes (e.g., increasing bowhead whale stock), changes in apex predator diets (e.g., polar bears eating less ringed seal), and changes in animal distributions (e.g., polar bears remaining closer to land over time). The Beaufort Sea model is a dynamic tool for Arctic Ocean natural resource management in the years to come.

  14. Sharing Remote and Local Information for Tracking Spring Breakup in the Mackenzie Delta and Beaufort Sea

    Science.gov (United States)

    Forbes, D. L.; Whalen, D.; Fraser, P.

    2015-12-01

    The Mackenzie Delta is the second largest on the Arctic Ocean, covering 13 000 km2. The annual flood regime in the delta is dominated by the spring snowmelt freshet and associated ice breakup, as water from the south arrives in the ice-covered delta and spreads over bottomfast and adjacent floating sea ice at the delta front. The complex processes of water-ice interaction, flow partitioning, and overbank flooding to replenish waters in 43 000 delta lakes threaten community, transportation, subsistence, and energy infrastructure in the delta. The annual breakup season is a time of rejuvenation, excitement, and anxiety for delta residents and stakeholders. To track the progress of breakup and meet the need for knowledge dissemination to the local communities, a Mackenzie-Beaufort breakup newsletter has been produced by Natural Resources Canada on a quasi-daily basis during the May-June spring flood season for 10 years, and distributed to an e-mail list that grew to over 300 subscribers. This provides near real-time tracking of water levels and breakup using on-line gauges (Environment Canada), daily MODIS satellite imagery (NASA), Landsat imagery (USGS) and intermittent radar imagery (various sources). In earlier years, information was also supplied from field programs operating in the delta during breakup, but changing priorities and funding have reduced the number of outside researchers present during these critical weeks. Meanwhile the number of local contributors has grown, providing observations and photographs to share with the local, regional and global readership. In this way the newsletter evolved into a two-way communication tool and community portal. The newsletter is a chronicle of each breakup season and a key resource for territorial and municipal managers, subsistence organizations, and emergency response agencies, with routine requests for specific imagery in areas of concern. With the completion of 10 years under the present model, we are exploring

  15. Polar bear population status in the northern Beaufort Sea, Canada, 1971-2006

    Science.gov (United States)

    Stirling, I.; McDonald, T.L.; Richardson, E.S.; Regehr, E.V.; Amstrup, Steven C.

    2011-01-01

    Polar bears (Ursus maritimus) of the northern Beaufort Sea (NB) population occur on the perimeter of the polar basin adjacent to the northwestern islands of the Canadian Arctic Archipelago. Sea ice converges on the islands through most of the year. We used open-population capture–recapture models to estimate population size and vital rates of polar bears between 1971 and 2006 to: (1) assess relationships between survival, sex and age, and time period; (2) evaluate the long-term importance of sea ice quality and availability in relation to climate warming; and (3) note future management and conservation concerns. The highest-ranking models suggested that survival of polar bears varied by age class and with changes in the sea ice habitat. Model-averaged estimates of survival (which include harvest mortality) for senescent adults ranged from 0.37 to 0.62, from 0.22 to 0.68 for cubs of the year (COY) and yearlings, and from 0.77 to 0.92 for 2–4 year-olds and adults. Horvtiz-Thompson (HT) estimates of population size were not significantly different among the decades of our study. The population size estimated for the 2000s was 980 ± 155 (mean and 95% CI). These estimates apply primarily to that segment of the NB population residing west and south of Banks Island. The NB polar bear population appears to have been stable or possibly increasing slightly during the period of our study. This suggests that ice conditions have remained suitable and similar for feeding in summer and fall during most years and that the traditional and legal Inuvialuit harvest has not exceeded sustainable levels. However, the amount of ice remaining in the study area at the end of summer, and the proportion that continues to lie over the biologically productive continental shelf (Sea will eventually decline. Management and conservation practices for polar bears in relation to both aboriginal harvesting and offshore industrial activity will need to adapt.

  16. Arctic continental shelf morphology related to sea-ice zonation, Beaufort Sea, Alaska

    Science.gov (United States)

    Reimnitz, E.; Toimil, L.; Barnes, P.

    1978-01-01

    Landsat-1 and NOAA satellite imagery for the winter 1972-1973, and a variety of ice and sea-floor data were used to study sea-ice zonation and dynamics and their relation to bottom morphology and geology on the Beaufort Sea continental shelf of arctic Alaska. In early winter the location of the boundary between undeformed fast ice and westward-drifting pack ice of the Pacific Gyre is controlled by major coastal promontories. Pronounced linear pressure- and shear-ridges, as well as hummock fields, form along this boundary and are stabilized by grounding, generally between the 10- and 20-m isobaths. Slippage along this boundary occurs intermittently at or seaward of the grounded ridges, forming new grounded ridges in a widening zone, the stamukhi zone, which by late winter extends out to the 40-m isobath. Between intermittent events along the stamukhi zone, pack-ice drift and slippage is continuous along the shelf edge, at average rates of 3-10 km/day. Whether slippage occurs along the stamukhi zone or along the shelf edge, it is restricted to a zone several hundred meters wide, and ice seaward of the slip face moves at uniform rates without discernible drag effects. A causal relationship is seen between the spatial distribution of major ice-ridge systems and offshore shoals downdrift of major coastal promontories. The shoals appear to have migrated shoreward under the influence of ice up to 400 m in the last 25 years. The sea floor seaward of these shoals within the stamukhi zone shows high ice-gouge density, large incision depths, and a high degree of disruption of internal sedimentary structures. The concentration of large ice ridges and our sea floor data in the stamukhi zone indicate that much of the available marine energy is expended here, while the inner shelf and coast, where the relatively undeformed fast ice grows, are sheltered. There is evidence that anomalies in the overall arctic shelf profile are related to sea-ice zonation, ice dynamics, and bottom

  17. Inorganic carbon fluxes on the Mackenzie Shelf of the Beaufort Sea

    Science.gov (United States)

    Mol, Jacoba; Thomas, Helmuth; Myers, Paul G.; Hu, Xianmin; Mucci, Alfonso

    2018-02-01

    The Mackenzie Shelf in the southeastern Beaufort Sea is a region that has experienced large changes in the past several decades as warming, sea-ice loss, and increased river discharge have altered carbon cycling. Upwelling and downwelling events are common on the shelf, caused by strong, fluctuating along-shore winds, resulting in cross-shelf Ekman transport, and an alternating estuarine and anti-estuarine circulation. Downwelling carries dissolved inorganic carbon (DIC) and other remineralization products off the shelf and into the deep basin for possible long-term storage in the world's oceans. Upwelling carries DIC and nutrient-rich waters from the Pacific-origin upper halocline layer (UHL) onto the shelf. Profiles of DIC and total alkalinity (TA) taken in August and September of 2014 are used to investigate the cycling of carbon on the Mackenzie Shelf. The along-shore transport of water and the cross-shelf transport of DIC are quantified using velocity field output from a simulation of the Arctic and Northern Hemisphere Atlantic (ANHA4) configuration of the Nucleus of European Modelling of the Ocean (NEMO) framework. A strong upwelling event prior to sampling on the Mackenzie Shelf took place, bringing CO2-rich (elevated pCO2) water from the UHL onto the shelf bottom. The maximum on-shelf DIC flux was estimated at 16.9×103 mol C d-1 m-2 during the event. The maximum on-shelf transport of DIC through the upwelling event was found to be 65±15×10-3 Tg C d-1. TA and the oxygen isotope ratio of water (δ18O-H2O) are used to examine water-mass distributions in the study area and to investigate the influence of Pacific Water, Mackenzie River freshwater, and sea-ice melt on carbon dynamics and air-sea fluxes of carbon dioxide (CO2) in the surface mixed layer. Understanding carbon transfer in this seasonally dynamic environment is key to quantify the importance of Arctic shelf regions to the global carbon cycle and provide a basis for understanding how it will

  18. Inorganic carbon fluxes on the Mackenzie Shelf of the Beaufort Sea

    Directory of Open Access Journals (Sweden)

    J. Mol

    2018-02-01

    Full Text Available The Mackenzie Shelf in the southeastern Beaufort Sea is a region that has experienced large changes in the past several decades as warming, sea-ice loss, and increased river discharge have altered carbon cycling. Upwelling and downwelling events are common on the shelf, caused by strong, fluctuating along-shore winds, resulting in cross-shelf Ekman transport, and an alternating estuarine and anti-estuarine circulation. Downwelling carries dissolved inorganic carbon (DIC and other remineralization products off the shelf and into the deep basin for possible long-term storage in the world's oceans. Upwelling carries DIC and nutrient-rich waters from the Pacific-origin upper halocline layer (UHL onto the shelf. Profiles of DIC and total alkalinity (TA taken in August and September of 2014 are used to investigate the cycling of carbon on the Mackenzie Shelf. The along-shore transport of water and the cross-shelf transport of DIC are quantified using velocity field output from a simulation of the Arctic and Northern Hemisphere Atlantic (ANHA4 configuration of the Nucleus of European Modelling of the Ocean (NEMO framework. A strong upwelling event prior to sampling on the Mackenzie Shelf took place, bringing CO2-rich (elevated pCO2 water from the UHL onto the shelf bottom. The maximum on-shelf DIC flux was estimated at 16.9×103 mol C d−1 m−2 during the event. The maximum on-shelf transport of DIC through the upwelling event was found to be 65±15×10−3 Tg C d−1. TA and the oxygen isotope ratio of water (δ18O-H2O are used to examine water-mass distributions in the study area and to investigate the influence of Pacific Water, Mackenzie River freshwater, and sea-ice melt on carbon dynamics and air–sea fluxes of carbon dioxide (CO2 in the surface mixed layer. Understanding carbon transfer in this seasonally dynamic environment is key to quantify the importance of Arctic shelf regions to the global carbon cycle and provide a basis

  19. Sources and Reactivity of Terrestrial Organic Carbon to the Colville River Delta, Beaufort Sea, Alaska

    Science.gov (United States)

    Schreiner, K. M.; Bianchi, T. S.; Rosenheim, B. E.

    2014-12-01

    relatively thermochemically reactive and sourced from Pleistocene-aged yedoma-like deposits, and could contribute to increased OC mineralization in the Beaufort shelf. These results are the first to combine biomarker and ramped pyrolysis-14C analyses in an Arctic setting.

  20. Unique Footprint in the scl1.3 Locus Affects Adhesion and Biofilm Formation of the Invasive M3-Type Group A Streptococcus.

    Science.gov (United States)

    Bachert, Beth A; Choi, Soo J; LaSala, Paul R; Harper, Tiffany I; McNitt, Dudley H; Boehm, Dylan T; Caswell, Clayton C; Ciborowski, Pawel; Keene, Douglas R; Flores, Anthony R; Musser, James M; Squeglia, Flavia; Marasco, Daniela; Berisio, Rita; Lukomski, Slawomir

    2016-01-01

    The streptococcal collagen-like proteins 1 and 2 (Scl1 and Scl2) are major surface adhesins that are ubiquitous among group A Streptococcus (GAS). Invasive M3-type strains, however, have evolved two unique conserved features in the scl1 locus: (i) an IS1548 element insertion in the scl1 promoter region and (ii) a nonsense mutation within the scl1 coding sequence. The scl1 transcript is drastically reduced in M3-type GAS, contrasting with a high transcription level of scl1 allele in invasive M1-type GAS. This leads to a lack of Scl1 expression in M3 strains. In contrast, while scl2 transcription and Scl2 production are elevated in M3 strains, M1 GAS lack Scl2 surface expression. M3-type strains were shown to have reduced biofilm formation on inanimate surfaces coated with cellular fibronectin and laminin, and in human skin equivalents. Repair of the nonsense mutation and restoration of Scl1 expression on M3-GAS cells, restores biofilm formation on cellular fibronectin and laminin coatings. Inactivation of scl1 in biofilm-capable M28 and M41 strains results in larger skin lesions in a mouse model, indicating that lack of Scl1 adhesin promotes bacterial spread over localized infection. These studies suggest the uniquely evolved scl1 locus in the M3-type strains, which prevents surface expression of the major Scl1 adhesin, contributed to the emergence of the invasive M3-type strains. Furthermore these studies provide insight into the molecular mechanisms mediating colonization, biofilm formation, and pathogenesis of group A streptococci.

  1. Unique footprint in the scl1.3 locus affects adhesion and biofilm formation of the invasive M3-type group A Streptococcus

    Directory of Open Access Journals (Sweden)

    Beth Alexandra Bachert

    2016-08-01

    Full Text Available The streptococcal collagen-like proteins 1 and 2 (Scl1 and Scl2 are major surface adhesins that are ubiquitous among group A Streptococcus (GAS. Invasive M3-type strains, however, have evolved two unique conserved features in the scl1 locus: (i an IS1548 element insertion in the scl1 promoter region and (ii a nonsense mutation within the scl1 coding sequence. The scl1 transcript is drastically reduced in M3-type GAS, contrasting with a high transcription level of scl1 allele in invasive M1-type GAS. This leads to a lack of Scl1 expression in M3 strains. In contrast, while scl2 transcription and Scl2 production are elevated in M3 strains, M1 GAS lack Scl2 surface expression. M3-type strains were shown to have reduced biofilm formation on inanimate surfaces coated with cellular fibronectin and laminin, and in human skin equivalents. Repair of the nonsense mutation and restoration of Scl1 expression on M3-GAS cells, restores biofilm formation on cellular fibronectin and laminin coatings. Inactivation of scl1 in biofilm-capable M28 and M41 strains results in larger skin lesions in a mouse model, indicating that lack of Scl1 adhesin promotes bacterial spread over localized infection. These studies suggest the uniquely evolved scl1 locus in the M3-type strains, which prevents surface expression of the major Scl1 adhesin, contributed to the emergence of the invasive M3-type strains. Furthermore these studies provide insight into the molecular mechanisms mediating colonization, biofilm formation, and pathogenesis of group A streptococci.

  2. Effects of capturing and collaring on polar bears: findings from long-term research on the southern Beaufort Sea population

    Science.gov (United States)

    Rode, Karyn D.; Pagano, Anthony M.; Bromaghin, Jeffrey F.; Atwood, Todd C.; Durner, George M.; Simac, Kristin S.; Amstrup, Steven C.

    2014-01-01

    Context: The potential for research methods to affect wildlife is an increasing concern among both scientists and the public. This topic has a particular urgency for polar bears because additional research is needed to monitor and understand population responses to rapid loss of sea ice habitat.Aims: This study used data collected from polar bears sampled in the Alaska portion of the southern Beaufort Sea to investigate the potential for capture to adversely affect behaviour and vital rates. We evaluated the extent to which capture, collaring and handling may influence activity and movement days to weeks post-capture, and body mass, body condition, reproduction and survival over 6 months or more.Methods: We compared post-capture activity and movement rates, and relationships between prior capture history and body mass, body condition and reproductive success. We also summarised data on capture-related mortality.Key results: Individual-based estimates of activity and movement rates reached near-normal levels within 2–3 days and fully normal levels within 5 days post-capture. Models of activity and movement rates among all bears had poor fit, but suggested potential for prolonged, lower-level rate reductions. Repeated captures was not related to negative effects on body condition, reproduction or cub growth or survival. Capture-related mortality was substantially reduced after 1986, when immobilisation drugs were changed, with only 3 mortalities in 2517 captures from 1987–2013.Conclusions: Polar bears in the southern Beaufort Sea exhibited the greatest reductions in activity and movement rates 3.5 days post-capture. These shorter-term, post-capture effects do not appear to have translated into any long-term effects on body condition, reproduction, or cub survival. Additionally, collaring had no effect on polar bear recovery rates, body condition, reproduction or cub survival.Implications: This study provides empirical evidence that current capture

  3. Marine mammal observations collected by aircraft and ship and submitted as part of the ConocoPhillips and Shell Joint Monitoring Program in the Chukchi and Beaufort Seas, 2006-2010 (NODC Accession 0120532)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains vessel- and aircraft-based mammal sightings data and associated environmental data collected in the Chukchi and Beaufort seas during the open...

  4. Temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from HEALY in the Arctic Ocean and Beaufort Sea from 2003-09-11 to 2003-10-18 (NODC Accession 0115676)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0115676 includes biological, chemical, discrete sample, optical, physical and profile data collected from HEALY in the Arctic Ocean and Beaufort Sea...

  5. Effluent - discharge descriptions and other data collected from several platforms using salinometer and other instruments in the Beaufort Sea from 07 August 1985 to 01 September 1985 (NODC Accession 8600317)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — F144 data were collected using salinometer and other instruments in the Beaufort Sea from several platforms. Data were collected from 07 August 1985 to 01 September...

  6. Acoustics short-term passive monitoring using sonobuoys in the Bering, Chukchi, and Western Beaufort Seas conducted by Alaska Fisheries Scientific Center, National Marine Mammal Laboratory from 2007-08-01 to 2015-09-28 (NCEI Accession 0138863)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The National Marine Mammal Laboratory (NMML) has conducted passive acoustic monitoring in the Bering, Chukchi, and Western Beaufort Seas to determine spatio-temporal...

  7. Temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from HEALY in the Arctic Ocean and Beaufort Sea from 2004-07-18 to 2004-08-26 (NODC Accession 0113548)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0113548 includes biological, chemical, discrete sample, optical, physical and profile data collected from HEALY in the Arctic Ocean and Beaufort Sea...

  8. Profile data from CTD casts aboard the F/V Ocean Explorer in the Arctic Ocean and Beaufort Sea from 2008-08-06 to 2008-08-22 (NODC Accession 0001920)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This profile data aboard the F/V Ocean Explorer in the Arctic Ocean and Beaufort Sea from August 6, 2008 to August 22, 2008 was supported by the Minerals Management...

  9. Plankton and other data from net casts in the Beaufort Sea from the USCGC GLACIER and other platforms from 04 August 1972 to 17 May 1979 (NODC Accession 8000587)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Plankton and other data were collected using net casts in the Beaufort Sea from the USCGC GLACIER and other platforms from 04 August 1972 to 17 May 1979. Data were...

  10. Group Formation on a Line

    DEFF Research Database (Denmark)

    Kristensen, Gustav

    2010-01-01

    Artiklen viser at en nummerering af indsamlede evalueringsskemaer kan afsløre gruppedannelse blandt de tilhørende studenter på et stort undervisningshold. Gruppedannelsen viser sig ved at sequenser med ens bedømmelse afviger fra en tilfældig fordeling defineret som en negativ binomialfordeling, d...

  11. A randomized trial of individual versus group-format exercise and self-management in individuals with Parkinson’s disease and comorbid depression

    Directory of Open Access Journals (Sweden)

    Sajatovic M

    2017-05-01

    Full Text Available Martha Sajatovic,1,2 Angela L Ridgel,3 Ellen M Walter,1,4 Curtis M Tatsuoka,1,2 Kari Colón-Zimmermann,2 Riane K Ramsey,2 Elisabeth Welter,2 Steven A Gunzler,1,4 Christina M Whitney,1,4 Benjamin L Walter1,4 1Department of Neurology, Case Western Reserve University School of Medicine, 2Neurological and Behavioral Outcomes Center, University Hospitals Cleveland Medical Center, Cleveland, 3Department of Exercise Physiology, Kent State University, Kent, 4Movement Disorders Center, University Hospitals Cleveland Medical Center, Cleveland, OH, USA Background: Depression is common in people with Parkinson’s disease (PD, and exercise is known to improve depression and PD. However, lack of motivation and low self-efficacy can make exercise difficult for people with PD and comorbid depression (PD-Dep. A combined group exercise and chronic disease self-management (CDSM program may improve the likelihood that individuals will engage in exercise and will show a reduction in depression symptoms. The purpose of this study was to compare changes in depression in PD-Dep between individual versus group exercise plus CDSM and to examine participant adherence and perception of the interventions.Methods: Participants (N=30 were randomized to either Enhanced EXerCisE thErapy for PD (EXCEED; group CDSM and exercise or self-guided CDSM plus exercise. Outcomes were change in depression assessed with the Montgomery–Asberg Depression Rating Scale (MADRS, cognition, apathy, anxiety, sleep, quality of life, motor function, self-efficacy, and patient satisfaction.Results: Both groups showed significant improvement in MADRS (P<0.001 with no significant group difference. Individuals in EXCEED group enjoyed the group dynamics but noted difficulty with the fixed-time sessions.Conclusion: Both group CDSM plus exercise and self-guided CDSM plus exercise can improve depression in PD-Dep. These findings suggest that development of a remotely delivered group-based CDSM format

  12. Origin of pingo-like features on the Beaufort Sea shelf and their possible relationship to decomposing methane gas hydrates

    Science.gov (United States)

    Paull, C.K.; Ussler, W.; Dallimore, S.R.; Blasco, S.M.; Lorenson, T.D.; Melling, H.; Medioli, B.E.; Nixon, F.M.; McLaughlin, F.A.

    2007-01-01

    The Arctic shelf is currently undergoing dramatic thermal changes caused by the continued warming associated with Holocene sea level rise. During this transgression, comparatively warm waters have flooded over cold permafrost areas of the Arctic Shelf. A thermal pulse of more than 10??C is still propagating down into the submerged sediment and may be decomposing gas hydrate as well as permafrost. A search for gas venting on the Arctic seafloor focused on pingo-like-features (PLFs) on the Beaufort Sea Shelf because they may be a direct consequence of gas hydrate decomposition at depth. Vibracores collected from eight PLFs had systematically elevated methane concentrations. ROV observations revealed streams of methane-rich gas bubbles coming from the crests of PLFs. We offer a scenario of how PLFs may be growing offshore as a result of gas pressure associated with gas hydrate decomposition. Copyright 2007 by the American Geophysical Union.

  13. Methods for estimating the enthalpy of formation of inorganic compounds; thermochemical and crystallographic investigations of uranyl salts of group VI elements

    International Nuclear Information System (INIS)

    Brandenburg, N.P.

    1978-01-01

    The first part of this thesis is concerned with parameter methods for estimating the standard enthalpy of formation, ΔH 0 sub(f), of inorganic compounds. In this type of method the estimate is a function of parameters, assigned to cation and anion, respectively. The usefulness of a new estimation method is illustrated in the case of uranyl sulphide. In the second part of this thesis crystallographic and thermochemical properties of uranyl salts of group VI elements are described. Crystal structures are given for β-UO 2 SO 4 , UO 2 SeO 3 , and α-UO 2 SeO 4 . Thermochemical measurements have been restricted to the determination of ΔH 0 sub(f)(UO 2 SO 3 ) and ΔH 0 sub(f)(UO 2 TeO 3 ) by means of isoperibol solution calorimetry. (Auth.)

  14. Natural Gas Hydrates in the Offshore Beaufort-Mackenzie Basin-Study of a Feasible Energy Source II

    International Nuclear Information System (INIS)

    Majorowicz, J. A.; Hannigan, P. K.

    2000-01-01

    In the offshore part of Beaufort-Mackenzie Basin depth of methane hydrate stability reaches more than 1.5 km. However, there are areas in the western part of the basin where there are no conditions of methane hydrate stability. Construction of the first contour maps displaying thickness of hydrate stability zones as well as hydrate stability zone thicknesses below permafrost in the offshore area, shows that these zones can reach 1200 m and 900 m, respectively. Depth to the base of ice-bearing relict permafrost under the sea (depth of the -1 o C isotherm-ice-bearing permafrost base) and regional variations of geothermal gradient are the main controlling factors. Hydrostatic pressures in the upper 1500 m are the rule. History of methane hydrate stability zone is related mainly to the history of permafrost and it reached maximum depth in early Holocene. More recently, the permafrost and hydrate zone is diminishing because of sea transgression. Reevaluation of the location of possible gas hydrate occurrences is done from the analysis of well logs and other indicators in conjunction with knowledge of the hydrate stability zone. In the offshore Beaufort-Mackenzie Basin, methane hydrate occurs in 21 wells. Nine of these locations coincides with underlying conventional hydrocarbon occurrences. Previous analyses place some of the hydrate occurrences at greater depths than proposed for the methane hydrate-stability zone described in this study. Interpretation of geological cross sections and maps of geological sequences reveals that hydrates are occurring in the Iperk-Kugmallit sequence. Hydrate-gas contact zones, however, are possible in numerous situations. As there are no significant geological seals in the deeper part of the offshore basin (all hydrates are within Iperk), it is suggested that overlying permafrost and hydrate stability zone acted as the only trap for upward migrating gas during the last tens of thousand of years (i.e., Sangamonian to Holocene)

  15. Hematology of southern Beaufort Sea polar bears (2005-2007): Biomarker for an arctic ecosystem health sentinel

    Science.gov (United States)

    Kirk, Cassandra M.; Amstrup, Steven C.; Swor, Rhonda; Holcomb, Darce; O'Hara, T. M.

    2010-01-01

    Declines in sea-ice habitats have resulted in declining stature, productivity, and survival of polar bears in some regions. With continuing sea-ice declines, negative population effects are projected to expand throughout the polar bear's range. Precise causes of diminished polar bear life history performance are unknown, however, climate and sea-ice condition change are expected to adversely impact polar bear (Ursus maritimus) health and population dynamics. As apex predators in the Arctic, polar bears integrate the status of lower trophic levels and are therefore sentinels of ecosystem health. Arctic residents feed at the apex of the ecosystem, thus polar bears can serve as indicators of human health in the Arctic. Despite their value as indicators of ecosystem welfare, population-level health data for U.S. polar bears are lacking. We present hematological reference ranges for southern Beaufort Sea polar bears. Hematological parameters in southern Beaufort Sea polar bears varied by age, geographic location, and reproductive status. Total leukocytes, lymphocytes, monocytes, eosinophils, and serum immunoglobulin G were significantly greater in males than females. These measures were greater in nonlactating females ages ???5, than lactating adult females ages ???5, suggesting that females encumbered by young may be less resilient to new immune system challenges that may accompany ongoing climate change. Hematological values established here provide a necessary baseline for anticipated changes in health as arctic temperatures warm and sea-ice declines accelerate. Data suggest that females with dependent young may be most vulnerable to these changes and should therefore be a targeted cohort for monitoring in this sentinel. ?? 2010 International Association for Ecology and Health.

  16. Hematology of southern Beaufort Sea polar bears (2005-2007): biomarker for an Arctic ecosystem health sentinel.

    Science.gov (United States)

    Kirk, Cassandra M; Amstrup, Steven; Swor, Rhonda; Holcomb, Darce; O'Hara, Todd M

    2010-09-01

    Declines in sea-ice habitats have resulted in declining stature, productivity, and survival of polar bears in some regions. With continuing sea-ice declines, negative population effects are projected to expand throughout the polar bear's range. Precise causes of diminished polar bear life history performance are unknown, however, climate and sea-ice condition change are expected to adversely impact polar bear (Ursus maritimus) health and population dynamics. As apex predators in the Arctic, polar bears integrate the status of lower trophic levels and are therefore sentinels of ecosystem health. Arctic residents feed at the apex of the ecosystem, thus polar bears can serve as indicators of human health in the Arctic. Despite their value as indicators of ecosystem welfare, population-level health data for U.S. polar bears are lacking. We present hematological reference ranges for southern Beaufort Sea polar bears. Hematological parameters in southern Beaufort Sea polar bears varied by age, geographic location, and reproductive status. Total leukocytes, lymphocytes, monocytes, eosinophils, and serum immunoglobulin G were significantly greater in males than females. These measures were greater in nonlactating females ages ≥5, than lactating adult females ages ≥5, suggesting that females encumbered by young may be less resilient to new immune system challenges that may accompany ongoing climate change. Hematological values established here provide a necessary baseline for anticipated changes in health as arctic temperatures warm and sea-ice declines accelerate. Data suggest that females with dependent young may be most vulnerable to these changes and should therefore be a targeted cohort for monitoring in this sentinel.

  17. Evaluation of the anthropogenic radionuclide concentrations in sediments and fauna collected in the Beaufort Sea and northern Alaska

    International Nuclear Information System (INIS)

    Efurd, D.W.; Miller, G.G.; Rokop, D.J.

    1997-07-01

    This study was performed to establish a quality controlled data set about the levels of radio nuclide activity in the environment and in selected biota in the U.S. Arctic. Sediment and biota samples were collected by the National Oceanic and Atmospheric Administration (NOAA), the National Biological Service, and the North Slope Borough's Department of Wildlife Management to determine the impact of anthropogenic radionuclides in the Arctic. The results summarized in this report are derived from samples collected in northwest Alaska with emphasis on species harvested for subsistence in Barrow, Alaska. Samples were analyzed for the anthropogenic radionuclides 90 Sr, 137 Cs, 238 Pu, 239 Pu, 240 Pu and 241 Am. The naturally occurring radionuclides 40 K, 212 Pb and 214 Pb were also measured. One goal of this study was to determine the amounts of anthropogenic radionuclides present in the Beaufort Sea. Sediment samples were isotopically fingerprinted to determine the sources of radio nuclide activities. Biota samples of subsistence and ecological value were analyzed to search for evidence of bio-accumulation of radionuclides and to determine the radiation exposures associated with subsistence living in northern Alaska. The anthropogenic radio nuclide content of sediments collected in the Beaufort Sea was predominantly the result of the deposition of global fallout. No other sources of anthropogenic radionuclides could be conclusively identified in the sediments. The anthropogenic radio nuclide concentrations in fish, birds and mammals were very low. Assuming that ingestion of food is an important pathway leading to human contact with radioactive contaminants and given the dietary patterns in coastal Arctic communities, it can be surmised that marine food chains are presently not significantly affected

  18. Analyse des effets de deux modalités de constitution des groupes dans un dispositif hybride de formation à distance

    Directory of Open Access Journals (Sweden)

    Christian Depover

    2004-01-01

    Full Text Available Cette étude porte sur les effets de deux modalités de constitution des groupes (spontané versus contrasté dans un dispositif hybride de formation à distance destiné à des étudiants universitaires. Les scénarios d’apprentissage mis en œuvre à l’occasion de cette expérience reposent sur l’utilisation des cartes conceptuelles comme support au travail collaboratif. Les résultats observés n’ont pas permis de mettre en évidence de différence quant à la densité conceptuelle des cartes ou au nombre d’unités de sens produites. Par contre, il apparaît que les unités de sens qui concernent les activités de planification et les commentaires métacognitifs sont nettement plus nombreuses au sein des groupes constitués par pairage contrasté. Une corrélation positive entre l’intensité des interactions à l’intérieur du forum et la densité conceptuelle des cartes produites a également été mise en évidence pour les groupes constitués sur la base d’un pairage contrasté. En ce qui concerne le pairage spontané, nos résultats indiquent que les paires constituées témoignent d’un comportement plus homogène, se révèlent plus collaboratives et consacrent moins d’effort à la planification du travail de groupe.

  19. Stability Zone of Natural Gas Hydrates in a Permafrost-Bearing Region of the Beaufort-Mackenzie Basin: Study of a Feasible Energy Source (Geological Survey of Canada Contribution No.1999275)

    International Nuclear Information System (INIS)

    Majorowicz, J. A.; Hannigan, P. K.

    2000-01-01

    Analysis of geological and geophysical data from 150 wells in the Beaufort-Mackenzie region(study area between 68 deg. 30'-70 deg. 00'N and 131 deg. -39 deg. W) led to reinterpretation of the depth of methane hydrate stability and construction of the first contour maps displaying thickness of hydrate stability zones as well as hydrate stability zone thicknesses below permafrost. Calculations were based on construction of temperature-depth profiles incorporating regional heat-flow values, temperature at the base of ice-bearing permafrost, and models relating thermal conductivity with depth. Data analysis indicates the presence and extent of the methane hydrate stability zone is related mainly to the history of permafrost development and less so by the relatively small regional variations of temperature gradients. Analysis of well logs and other indicators in conjunction with knowledge of the hydrate stability zone allows reevaluation of the location of possible gas hydrate occurrences. Log analysis indicates that in the onshore and shallow sea area of the Beaufort-Mackenzie Basin, methane hydrate occurs in 27 wells. Fifteen of these locations coincides with underlying conventional hydrocarbon occurrences. Previous analyses place some of the hydrate occurrences at greater depths than proposed for the methane hydrate stability zone described in this study. Interpretation of geological cross sections reveals that hydrates are related mainly to sandy deltaic and delta-plain deposits in Iperk, Kugmallit, and Reindeer sequences although additional hydrate picks have been inferred in other sequences, such as Richards. Overlying permafrost may act as seal for hydrate accumulations; however, the thickness of permafrost and its related hydrate stability zone fluctuated during geological time. It is interpreted that only in the last tens of thousand of years (i.e., Sangamonian to Holocene), conditions for hydrates changed from nonstable to stable. During Early and Late

  20. Galaxy And Mass Assembly (GAMA): Gas Fueling of Spiral Galaxies in the Local Universe. I. The Effect of the Group Environment on Star Formation in Spiral Galaxies

    Science.gov (United States)

    Grootes, M. W.; Tuffs, R. J.; Popescu, C. C.; Norberg, P.; Robotham, A. S. G.; Liske, J.; Andrae, E.; Baldry, I. K.; Gunawardhana, M.; Kelvin, L. S.; Madore, B. F.; Seibert, M.; Taylor, E. N.; Alpaslan, M.; Brown, M. J. I.; Cluver, M. E.; Driver, S. P.; Bland-Hawthorn, J.; Holwerda, B. W.; Hopkins, A. M.; Lopez-Sanchez, A. R.; Loveday, J.; Rushton, M.

    2017-03-01

    We quantify the effect of the galaxy group environment (for group masses of 1012.5-1014.0 M ⊙) on the current star formation rate (SFR) of a pure, morphologically selected sample of disk-dominated (I.e., late-type spiral) galaxies with redshift ≤0.13. The sample embraces a full representation of quiescent and star-forming disks with stellar mass M * ≥ 109.5 M ⊙. We focus on the effects on SFR of interactions between grouped galaxies and the putative intrahalo medium (IHM) of their host group dark matter halos, isolating these effects from those induced through galaxy-galaxy interactions, and utilizing a radiation transfer analysis to remove the inclination dependence of derived SFRs. The dependence of SFR on M * is controlled for by measuring offsets Δlog(ψ *) of grouped galaxies about a single power-law relation in specific SFR, {\\psi }* \\propto {M}* -0.45+/- 0.01, exhibited by non-grouped “field” galaxies in the sample. While a small minority of the group satellites are strongly quenched, the group centrals and a large majority of satellites exhibit levels of ψ * statistically indistinguishable from their field counterparts, for all M *, albeit with a higher scatter of 0.44 dex about the field reference relation (versus 0.27 dex for the field). Modeling the distributions in Δlog(ψ *), we find that (I) after infall into groups, disk-dominated galaxies continue to be characterized by a similar rapid cycling of gas into and out of their interstellar medium shown prior to infall, with inflows and outflows of ˜1.5-5 x SFR and ˜1-4 x SFR, respectively; and (II) the independence of the continuity of these gas flow cycles on M * appears inconsistent with the required fueling being sourced from gas in the circumgalactic medium on scales of ˜100 kpc. Instead, our data favor ongoing fueling of satellites from the IHM of the host group halo on ˜Mpc scales, I.e., from gas not initially associated with the galaxies upon infall. Consequently, the color

  1. Influence of surface oxygenated groups on the formation of active Cu species and the catalytic activity of Cu/AC catalyst for the synthesis of dimethyl carbonate

    Science.gov (United States)

    Zhang, Guoqiang; Li, Zhong; Zheng, Huayan; Hao, Zhiqiang; Wang, Xia; Wang, Jiajun

    2016-12-01

    Activated carbon (AC) supported Cu catalysts are employed to study the influence of surface oxygenated groups on the formation of active Cu species and the catalytic activity of Cu/AC catalyst for oxidative carbonylation of methanol to dimethyl carbonate (DMC). The AC supports are thermal treated under different temperatures in order to adjust the levels of surface oxygenated groups. The AC supports are characterized by BET, TPD-MS and XRD, and the Cu/AC catalysts are characterized by BET, XRD, TEM, XPS, AAS, CH3OH-TPD and N2O chemisorption. The results show that as the treatment temperature is below 800 °C, the BET surface area of the corresponding AC supports are nearly unchanged and close to that of the original AC (1529.6 m2/g). But as the thermal treatment temperature is elevated from 1000 to 1600 °C, the BET surface area of AC supports gradually decreases from 1407.6 to 972.2 m2/g. After loading of Cu, the BET surface area of copper catalysts is in the range of 834.4 to 1545.3 m2/g, which is slightly less than that of the respective supports. When AC is thermal treated at 400 and 600 °C, the unstable carboxylic acid and anhydrides groups are selectively removed, which has weakened the mobility and agglomeration of Cu species during the calcination process, and thus improve the Cu species dispersion over AC support. But as the treatment temperature is elevated from 600 °C to 1200 °C, the Cu species dispersion begins to decline suggesting further removal of stable surface oxygenated groups is unfavorable for Cu species dispersion. Moreover, higher thermal treatment temperature (above 1200 °C) promotes the graphitization degree of AC and leds to the decrease of Cu loading on AC support. Meanwhile, the removal of surface oxygenated groups by thermal treatment is conducive to the formation of more π-sites, and thus promote the reduction of Cu2+ to Cu+ and Cu0 as active centers. The specific surface area of (Cu+ + Cu0) is improved by thermal treatment of AC

  2. A snake venom group IIA PLA2 with immunomodulatory activity induces formation of lipid droplets containing 15-d-PGJ2 in macrophages.

    Science.gov (United States)

    Giannotti, Karina Cristina; Leiguez, Elbio; Carvalho, Ana Eduarda Zulim de; Nascimento, Neide Galvão; Matsubara, Márcio Hideki; Fortes-Dias, Consuelo Latorre; Moreira, Vanessa; Teixeira, Catarina

    2017-06-22

    Crotoxin B (CB) is a catalytically active group IIA sPLA 2 from Crotalus durissus terrificus snake venom. In contrast to most GIIA sPLA 2 s, CB exhibits anti-inflammatory effects, including the ability to inhibit leukocyte functions. Lipid droplets (LDs) are lipid-rich organelles associated with inflammation and recognized as a site for the synthesis of inflammatory lipid mediators. Here, the ability of CB to induce formation of LDs and the mechanisms involved in this effect were investigated in isolated macrophages. The profile of CB-induced 15-d-PGJ 2 (15-Deoxy-Delta-12,14-prostaglandin J 2 ) production and involvement of LDs in 15-d-PGJ 2 biosynthesis were also investigated. Stimulation of murine macrophages with CB induced increased number of LDs and release of 15-d-PGJ 2 . LDs induced by CB were associated to PLIN2 recruitment and expression and required activation of PKC, PI3K, MEK1/2, JNK, iPLA 2 and PLD. Both 15-d-PGJ 2 and COX-1 were found in CB-induced LDs indicating that LDs contribute to the inhibitory effects of CB by acting as platform for synthesis of 15-d-PGJ 2 , a pro-resolving lipid mediator. Together, our data indicate that an immunomodulatory GIIA sPLA 2 can directly induce LD formation and production of a pro-resolving mediator in an inflammatory cell and afford new insights into the roles of LDs in resolution of inflammatory processes.

  3. Development of a Web-Based Intervention for Addressing Distress in Caregivers of Patients Receiving Stem Cell Transplants: Formative Evaluation With Qualitative Interviews and Focus Groups

    Science.gov (United States)

    Pensak, Nicole Amoyal; Joshi, Tanisha; Simoneau, Teresa; Kilbourn, Kristin; Carr, Alaina; Kutner, Jean; Laudenslager, Mark L

    2017-06-22

    Caregivers of cancer patients experience significant burden and distress including depression and anxiety. We previously demonstrated the efficacy of an eight session, in-person, one-on-one stress management intervention to reduce distress in caregivers of patients receiving allogeneic hematopoietic stem cell transplants (allo-HSCT). The objective of this study was to adapt and enhance the in-person caregiver stress management intervention to a mobilized website (eg, tablet, smartphone, or computer-based) for self-delivery in order to enhance dissemination to caregiver populations most in need. We used an established approach for development of a mhealth intervention, completing the first two research and evaluation steps: Step One: Formative Research (eg, expert and stakeholder review from patients, caregivers, and palliative care experts) and Step Two: Pretesting (eg, Focus Groups and Individual Interviews with caregivers of patients with autologous HSCT (auto-HSCT). Step one included feedback elicited for a mock-up version of Pep-Pal session one from caregiver, patients and clinician stakeholders from a multidisciplinary palliative care team (N=9 caregivers and patient stakeholders and N=20 palliative care experts). Step two included two focus groups (N=6 caregivers) and individual interviews (N=9 caregivers) regarding Pep-Pal's look and feel, content, acceptability, and potential usability/feasibility. Focus groups and individual interviews were audio-recorded. In addition, individual interviews were transcribed, and applied thematic analysis was conducted in order to gain an in-depth understanding to inform the development and refinement of the mobilized caregiver stress management intervention, Pep-Pal (PsychoEducation and skills for Patient caregivers). Overall, results were favorable. Pep-Pal was deemed acceptable for caregivers of patients receiving an auto-HSCT. The refined Pep-Pal program consisted of 9 sessions (Introduction to Stress, Stress and the

  4. Geology and mineral resources of the Florence, Beaufort, Rocky Mount, and Norfolk 10 x 20 NTMS quadrangles. National Uranium Resource Evaluation program

    International Nuclear Information System (INIS)

    Harris, W.B.

    1982-08-01

    This document provides geologic and mineral resources data for previously-issued Savannah River Laboratory hydrogeochemical and stream sediment reports of the Beaufort, Florence, Norfolk, and Rocky Mount 1 0 x 2 0 National Topographic Map Series quadrangles in the southeastern United States. This report is issued in draft form, without detailed technical and copy editing. This was done to make the report available to the public before the end of the National Uranium Resource Evaluation program

  5. Monitoring of Hydrocarbons in Sediment and Biota Related to Oil and Gas Development in Near- and Off-Shore Areas of the Arctic Beaufort Sea, Alaska

    Science.gov (United States)

    Durell, G.; Hardin, J.; Libby, S.

    2016-02-01

    There is increasing interest in extracting oil and gas from offshore environments of Alaska. The Arctic Nearshore Impact Monitoring in Development Area (ANIMIDA) project, started in 1999, has been producing information to evaluate potential effects of oil and gas activities in the Alaskan Beaufort Sea. ANIMIDA was preceded by the Beaufort Sea Monitoring Program. Monitoring has mostly been in pre-drilling locations, but also during development and production periods. Surveys were conducted to assess bottom sediment, sediment cores, suspended sediment, and biota for polycyclic aromatic hydrocarbons (PAH), saturated hydrocarbons, biological and petroleum markers, and geophysical parameters. The concentrations measured in sediments and biota were at or near background throughout most of the Beaufort Sea. There were no significant differences between exploration, production, and background locations, and the concentrations were consistently below those of ecological concern. For instance, TPAH in sediment ranged from below 100 to about 1,000 µg/kg and were controlled primarily by sediment characteristics (e.g., grain size and organic carbon). Hydrocarbons in sediments were from petrogenic, pyrogenic, and biogenic sources. Small areas with indications of input of anthropogenic chemicals were identified by sensitive diagnostic analysis techniques and are possibly associated with historic exploratory drilling and vessels. Sediment cores indicate a uniform historical deposition of hydrocarbons, although some evidence of past drilling activities were observed. Fish, amphipods, and clams contained background levels of hydrocarbons and showed no evidence of effects from accumulation of contaminants; TPAH concentrations were below 100 µg/kg in most biota. Noteworthy interannual fluctuations were observed for PAH concentrations in sediment and biota, likely due to winnowing of sediment fines by large storms and annual variations in river discharges. Significant natural sources

  6. Geology and mineral resources of the Florence, Beaufort, Rocky Mount, and Norfolk 1/sup 0/ x 2/sup 0/ NTMS quadrangles. National Uranium Resource Evaluation program

    Energy Technology Data Exchange (ETDEWEB)

    Harris, W.B.

    1982-08-01

    This document provides geologic and mineral resources data for previously-issued Savannah River Laboratory hydrogeochemical and stream sediment reports of the Beaufort, Florence, Norfolk, and Rocky Mount 1/sup 0/ x 2/sup 0/ National Topographic Map Series quadrangles in the southeastern United States. This report is issued in draft form, without detailed technical and copy editing. This was done to make the report available to the public before the end of the National Uranium Resource Evaluation program.

  7. Mixed-Format Test Score Equating: Effect of Item-Type Multidimensionality, Length and Composition of Common-Item Set, and Group Ability Difference

    Science.gov (United States)

    Wang, Wei

    2013-01-01

    Mixed-format tests containing both multiple-choice (MC) items and constructed-response (CR) items are now widely used in many testing programs. Mixed-format tests often are considered to be superior to tests containing only MC items although the use of multiple item formats leads to measurement challenges in the context of equating conducted under…

  8. Dynamic ocean topography from CryoSat-2: examining recent changes in ice-ocean stress and advancing a theory for Beaufort Gyre stabilization

    Science.gov (United States)

    Dewey, S.; Morison, J.; Kwok, R.; Dickinson, S.; Morison, D.; Andersen, R.

    2017-12-01

    Model and sparse observational evidence has shown the ocean current speed in the Beaufort Gyre to have increased and recently stabilized. However, full-basin altimetric observations of dynamic ocean topography (DOT) and ocean surface currents have yet to be applied to the dynamics of gyre stabilization. DOT fields from retracked CryoSat-2 retrievals in Arctic Ocean leads have enabled us to calculate 2-month average ocean geostrophic currents. These currents are crucial to accurately computing ice-ocean stress, especially because they have accelerated so that their speed rivals that of the overlying sea ice. Given these observations, we can shift our view of the Beaufort Gyre as a system in which the wind drives the ice and the ice drives a passive ocean to a system with the following feedback: After initial input of energy by wind, ice velocity decreases due to water drag and internal ice stress and the ocean drives the ice, reversing Ekman pumping and decelerating the gyre. This reversal changes the system from a persistently convergent regime to one in which freshwater is released from the gyre and doming of the gyre decreases, without any change in long-term average wind stress curl. Through these processes, the ice-ocean stress provides a key feedback in Beaufort Gyre stabilization.

  9. Subsea ice-bearing permafrost on the U.S. Beaufort Margin: 1. Minimum seaward extent defined from multichannel seismic reflection data

    Science.gov (United States)

    Brothers, Laura; Herman, Bruce M.; Hart, Patrick E.; Ruppel, Carolyn D.

    2016-01-01

    Subsea ice-bearing permafrost (IBPF) and associated gas hydrate in the Arctic have been subject to a warming climate and saline intrusion since the last transgression at the end of the Pleistocene. The consequent degradation of IBPF is potentially associated with significant degassing of dissociating gas hydrate deposits. Previous studies interpreted the distribution of subsea permafrost on the U.S. Beaufort continental shelf based on geographically sparse data sets and modeling of expected thermal history. The most cited work projects subsea permafrost to the shelf edge (∼100 m isobath). This study uses a compilation of stacking velocity analyses from ∼100,000 line-km of industry-collected multichannel seismic reflection data acquired over 57,000 km2 of the U.S. Beaufort shelf to delineate continuous subsea IBPF. Gridded average velocities of the uppermost 750 ms two-way travel time range from 1475 to 3110 m s−1. The monotonic, cross-shore pattern in velocity distribution suggests that the seaward extent of continuous IBPF is within 37 km of the modern shoreline at water depths < 25 m. These interpretations corroborate recent Beaufort seismic refraction studies and provide the best, margin-scale evidence that continuous subsea IBPF does not currently extend to the northern limits of the continental shelf.

  10. Behavior of bowhead whales of the Davis Strait and Bering/Beaufort stocks versus regional differences in human activities. Final report on Phase 2

    International Nuclear Information System (INIS)

    Miller, G.W.; Davis, R.A.; Richardson, W.J.

    1991-07-01

    The objectives were to determine (1) whether there are differences in behavior between the Bering/Chukchi/Beaufort and the Davis Strait/Baffin Bay populations and (2), if so, whether the differences might be attributable to the long-term cumulative effects of exposure to the presumed greater amount of human activity in the former area. Phase 1 showed that there are some differences in behavior. The Phase 2 report documents the relative amounts of human activity in the two areas in 1974-86, and evaluates whether regional differences in whale behavior and in human activities may be related. Activities considered include bowhead hunting and other subsistence activities, commercial fishing and shipping, marine seismic exploration, offshore oil exploration, and low-level aircraft flights. Bering/Beaufort bowheads were subjected to at least 3-5 times as much human activity in 1974-86. Most differences in behavior between the two stocks were better explained by environmental or biological factors than by disturbance. However, for bowheads migrating in autumn, regional differences in behavior may be related to the whaling that occurs in the Beaufort Sea in autumn

  11. Final Scientific/Technical Report of Gas Hydrate Dynamics on the Alaskan Beaufort Continental Slope: Modeling and Field Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Hornbach, Matthew J [Southern Methodist Univ., Dallas, TX (United States); Colwell, Frederick S [Oregon State Univ., Corvallis, OR (United States); Harris, Robert [Oregon State Univ., Corvallis, OR (United States)

    2017-07-06

    Methane Hydrates, a solid form of methane and water, exist at high pressures and low temperatures, occurs on every continental margin on Earth, represents one of the largest reservoirs of carbon on the planet, and, if destabilized, may play an important role in both slope stability and climate change. For decades, researchers have studied methane hydrates with the hope of determining if methane hydrates are destabilizing, and if so, how this destabilization might impact slope stability and ocean/atmosphere carbon budgets. In the past ~5 years, it has become well established that the upper “feather-edge” of methane hydrate stability (intermediate water depths of ~200-500 meters below sea level) represents an important frontier for methane hydrates stability research, as this zone is most susceptible to destabilization due to minor fluctuations in ocean temperature in space and time. The Arctic Ocean—one of the fastest warming regions on Earth—is perhaps the best place to study possible changes to methane hydrate stability due to ocean warming. To address the stability of methane hydrates at intermediate ocean depths, Southern Methodist University in partnership with Oregon State University and The United State Geological Survey at Woods Hole began investigating methane hydrate stability in intermediate water depths below both the US Beaufort Sea and the Atlantic Margin, from 2012-2017. The work was funded by the Department of Energy’s (DOE) National Energy Technology Laboratory (NETL). The key goal of the SMU component of this study was to collect the first ever heat flow data in the Beaufort Sea and compare measured shallow (probe-based1) heat flow values with deeper (BSR-derived2) heat flow values, and from this, determine whether hydrates were in thermal equilibrium. In September 2016, SMU/OSU collected the first ever heat flow measurements in the US Beaufort Sea. Despite poor weather and rough seas, the cruise was a success, with 116 heat flow

  12. Ideology, interest-group formation, and protest: the case of the anti-nuclear power movement, the Clamshell Alliance, and the New Left

    International Nuclear Information System (INIS)

    Cohen, E.M.

    1981-01-01

    The thesis analyzes the development of the Clamshell Alliance, the first and most successful anti-nuclear power protest group. The key question the dissertation asks is how did this organization stage such popular and well-attended protests during a period when leftist political activity seemed to have died out, and little mass protest was taking place. The thesis also explores why the Clamshell Alliance disintegrated at the same time as the anti-nuclear power movement's cause was gaining public acceptance in the wake of the Three Mile Island power-plant accident. The thesis finds that the principal resources the Clamshell drew upon to solve the problems of organizational formation were the activists, organizations, and ideology of the surviving New Left. The dissertation studies the struggles of the Clamshell Alliance as an example of the recurrent problems of leftist political activism in the U.S. It is concluded that only under special conditions can protest outside of regular political channels be both popular and effective. It is also proved that a larger organizational and ideological legacy of the sixties remains than is generally recongnized. Leftist beliefs continued to have adherents even after the protests stopped. Further, many individuals who came to political maturity after the sixties also were found to hold leftist beliefs. However, the political potential of this group can only be realized when an organization temporarily overcomes the barriers to mass leftist political action by developing an issue and a set of tactics that can appeal to leftists and nonleftists alike. Between such special acts of innovation the Left remains a political undercurrent outside of mainstream politics and without a means of effective influence because of its unwillingness to engage in conventional politics

  13. Paleomagnetic and magnetostratigraphic investigations of the whitehorse group/quartermaster (Dewey Lake) formation (upper permian-lowermost triassic) in the Palo Duro basin, northwest Texas, USA

    Science.gov (United States)

    Collins, Dylan R.

    In northwest Texas, upper Permian to lowermost Triassic hematite-cemented detrital sedimentary rocks, which include a small number of regionally extensive ash beds, were deposited during the time interval of the greatest mass extinction event sequences in Earth history. The magnetic polarity stratigraphy, as well as key rock magnetic properties, of the upper Whitehorse Group (WH) and Quartermaster formations (QM) at selected sections in the Palo Duro Basin, have been determined using thermal, and chemical demagnetization approaches and anisotropy of magnetic susceptibility, acquisition of isothermal remanent magnetization (IRM) and backfield demagnetization, and thermal demagnetization of three component IRM methods. Demagnetization results show that the WH/QM contains a primary/near-primary characteristic remanent magnetization at each level sampled and thus the magnetic polarity stratigraphy for each section can be compared with existing polarity time scales across the Permian-Triassic boundary. Estimated site mean directions yield a paleomagnetic pole for the latest Permian for North America of 57.8°N, 130.6°E from 38 sampled sites.

  14. Filamentation and light bullet formation dynamics in solid-state dielectric media with weak, moderate and strong anomalous group velocity dispersion

    International Nuclear Information System (INIS)

    Gražulevičiūtė, I; Garejev, N; Majus, D; Tamošauskas, G; A Dubietis; Jukna, V

    2016-01-01

    We present a series of measurements, which characterize filamentation dynamics of intense ultrashort laser pulses in the space–time domain, as captured by means of three-dimensional imaging technique in sapphire and fused silica, in the wavelength range of 1.45–2.25 μm, accessing the regimes of weak, moderate and strong anomalous group velocity dispersion (GVD). In the regime of weak anomalous GVD (at 1.45 μm), pulse splitting into two sub-pulses producing a pair of light bullets with spectrally shifted carrier frequencies in both nonlinear media is observed. In contrast, in the regimes of moderate (at 1.8 μm) and strong (at 2.25 μm) anomalous GVD we observe notably different transient dynamics, which however lead to the formation of a single self-compressed quasistationary light bullet with an universal spatiotemporal shape comprised of an extended ring-shaped periphery and a localized intense core that carries the self-compressed pulse. (paper)

  15. Filamentation and light bullet formation dynamics in solid-state dielectric media with weak, moderate and strong anomalous group velocity dispersion

    Science.gov (United States)

    Gražulevičiūtė, I.; Garejev, N.; Majus, D.; Jukna, V.; Tamošauskas, G.; Dubietis, A.

    2016-02-01

    We present a series of measurements, which characterize filamentation dynamics of intense ultrashort laser pulses in the space-time domain, as captured by means of three-dimensional imaging technique in sapphire and fused silica, in the wavelength range of 1.45-2.25 μm, accessing the regimes of weak, moderate and strong anomalous group velocity dispersion (GVD). In the regime of weak anomalous GVD (at 1.45 μm), pulse splitting into two sub-pulses producing a pair of light bullets with spectrally shifted carrier frequencies in both nonlinear media is observed. In contrast, in the regimes of moderate (at 1.8 μm) and strong (at 2.25 μm) anomalous GVD we observe notably different transient dynamics, which however lead to the formation of a single self-compressed quasistationary light bullet with an universal spatiotemporal shape comprised of an extended ring-shaped periphery and a localized intense core that carries the self-compressed pulse.

  16. Carbon sources in suspended particles and surface sediments from the Beaufort Sea revealed by molecular lipid biomarkers and compound-specific isotope analysis

    Directory of Open Access Journals (Sweden)

    I. Tolosa

    2013-03-01

    Full Text Available Molecular lipid biomarkers (hydrocarbons, alcohols, sterols and fatty acids and compound-specific isotope analysis of suspended particulate organic matter (SPM and surface sediments of the Mackenzie Shelf and slope (southeast Beaufort Sea, Arctic Ocean were studied in summer 2009. The concentrations of the molecular lipid markers, characteristic of known organic matter sources, were grouped and used as proxies to evaluate the relative importance of fresh algal, detrital algal, fossil, C3 terrestrial plants, bacterial and zooplankton material in the organic matter (OM of this area. Fossil and detrital algal contributions were the major fractions of the freshwater SPM from the Mackenzie River with ~34% each of the total molecular biomarkers. Fresh algal, C3 terrestrial, bacterial and zooplanktonic components represented much lower percentages, 17, 10, 4 and 80%, with a minor contribution of fossil and C3 terrestrial biomarkers. Characterization of the sediments revealed a major sink of refractory algal material mixed with some fresh algal material, fossil hydrocarbons and a small input of C3 terrestrial sources. In particular, the sediments from the shelf and at the mouth of the Amundsen Gulf presented the highest contribution of detrital algal material (60–75%, whereas those from the slope contained the highest proportion of fossil (40% and C3 terrestrial plant material (10%. Overall, considering that the detrital algal material is marine derived, autochthonous sources contributed more than allochthonous sources to the OM lipid pool. Using the ratio of an allochthonous biomarker (normalized to total organic carbon, TOC found in the sediments to those measured at the river mouth water, we estimated that the fraction of terrestrial material preserved in the sediments accounted for 30–40% of the total carbon in the inner shelf sediments, 17% in the outer shelf and Amundsen Gulf and up to 25% in the slope sediments. These estimates are low

  17. Coal geology of the Paleocene-Eocene Calvert Bluff Formation (Wilcox Group) and the Eocene Manning Formation (Jackson Group) in east-central Texas; field trip guidebook for the Society for Organic Petrology, Twelfth Annual Meeting, The Woodlands, Texas, August 30, 1995

    Science.gov (United States)

    Warwick, Peter D.; Crowley, Sharon S.

    1995-01-01

    The Jackson and Wilcox Groups of eastern Texas (fig. 1) are the major lignite producing intervals in the Gulf Region. Within these groups, the major lignite-producing formations are the Paleocene-Eocene Calvert Bluff Formation (Wilcox) and the Eocene Manning Formation (Jackson). According to the Keystone Coal Industry Manual (Maclean Hunter Publishing Company, 1994), the Gulf Coast basin produces about 57 million short tons of lignite annually. The state of Texas ranks number 6 in coal production in the United States. Most of the lignite is used for electric power generation in mine-mouth power plant facilities. In recent years, particular interest has been given to lignite quality and the distribution and concentration of about a dozen trace elements that have been identified as potential hazardous air pollutants (HAPs) by the 1990 Clean Air Act Amendments. As pointed out by Oman and Finkelman (1994), Gulf Coast lignite deposits have elevated concentrations of many of the HAPs elements (Be, Cd, Co, Cr, Hg, Mn, Se, U) on a as-received gm/mmBtu basis when compared to other United States coal deposits used for fuel in thermo-electric power plants. Although regulations have not yet been established for acceptable emissions of the HAPs elements during coal burning, considerable research effort has been given to the characterization of these elements in coal feed stocks. The general purpose of the present field trip and of the accompanying collection of papers is to investigate how various aspects of east Texas lignite geology might collectively influence the quality of the lignite fuel. We hope that this collection of papers will help future researchers understand the complex, multifaceted interrelations of coal geology, petrology, palynology and coal quality, and that this introduction to the geology of the lignite deposits of east Texas might serve as a stimulus for new ideas to be applied to other coal basins in the U.S. and abroad.

  18. Multiple embryos in the Lepidocyclina pustulosa group as possible indicators of palaeoenvironmental conditions: The case of the Late Eocene Toluviejo Formation (Sinú Domain, Caribbean, Colombia

    Science.gov (United States)

    Baumgartner-Mora, Claudia; Baumgartner, Peter O.; Rincón Martínez, Daniel; Salazar Ortiz, Edward A.

    2016-04-01

    The Middle-Late Eocene Toluviejo Formation of the Sinú-San Jacinto folded belt (Caribbean, Colombia) contains 15-75 m thick, grey, massive limestone sequences that are interbedded with terrigenous nearshore to offshore mudstones to quartzose sandstones and conglomerates. The formation accumulated in a transitional continent-ocean setting, probably on oceanic crust. We studied over 80 polished thin sections under light microscopy and cathodoluminescence (CL) to analyse carbonate microfacies and Larger Benthic Foraminifera (LBF). The overall facies distribution is 3-fold: (1) Facies close to the shoreline are dominated by low diversity operculinid assemblages, rich in detrital elements. (2) Shallow offshore facies are characterized by round lepidocyclinids, associated with, and often encrusted by, corallinacean algae, Sporolithon and structureless microbial crusts. The matrix is rich in carbonate/detrital mud and sand-sized detritals. (3) Distal offshore facies on structural highs show abundance of flat, current-sorted lepidoclinids without a noticeable detrital component. Facies 1 and 2 are clearly under the influence of suspension- and dissolved-nutrient input, probably carried offshore by freshwater lids of river plumes. Facies (2) contains abundant specimens of the Lepidocyclina pustulosa group of which the macrospheric forms show complicated embryonic apparatuses, which suppose double or multiple embryos. Detailed observation under CL allows to count up to 6-8 embryos, often seen aligned in the equatorial plane. The embryonic apparatus occupies often more than half of the diameter of specimens. The tendency towards large, very flat embryonic apparatuses (diameter measured in axial cuts up to 2,5 mm for a thickness of 0.2-0.3 mm) is closely correlated with abundant coralgal and microbial encrustations, oxide-stained carbonate/detrital mud and probably some preserved organic matter. The presence of multiple embryos has been reported by several authors and has

  19. Petrography and geochemistry of selected lignite beds in the Gibbons Creek mine (Manning Formation, Jackson Group, Paleocene) of east-central Texas

    Science.gov (United States)

    Warwick, Peter D.; Crowley, Sharon S.; Ruppert, Leslie F.; Pontolillo, James

    1997-01-01

    This study examined the petrographic and geochemical characteristics of two lignite beds (3500 and 4500 beds, Manning Formation, Jackson Group, Eocene) that are mined at the Gibbons Creek mine in east-central Texas. The purpose of the study was to identify the relations among sample ash yield, coal petrography, and trace-element concentrations in lignite and adjoining rock layers of the Gibbons Creek mine. Particular interest was given to the distribution of 12 environmentally sensitive trace elements (As, Be, Cd, Cr, Co, Hg, Mn, Ni, Pb, Sb, Se, and U) that have been identified as potentially hazardous air pollutants (HAPs) in the United States Clean Air Act Amendments of 1990. Eleven lignite, floor, and rock parting samples were collected from incremental channel samples of the 3500 and 4500 beds that were exposed in a highwall of pit A3 at the Gibbons Creek mine. Short proximate and ultimate and forms of sulfur analyses were performed on all lignite samples, and lignite and rock samples were analyzed for 60 major, minor and trace elements. Representative splits of all lignite samples were ground and cast into pellets, and polished for petrographic analyses in blue-light fluorescence and reflected white light to determine liptinite, inertinite, and huminite maceral group percentages. The following observations summarize our results and conclusions about the geochemistry, petrography, and sedimentology of the 3500 and 4500 beds of the Gibbons Creek lignite deposit: (1) Weighted average dry (db) ash yield for the two beds is 29.7%, average total sulfur content is 2.6%, and average calorific value is 7832 Btu (18.22 MJ/kg). Ash yields are greatest in the lower bench (59.33% db) of the 3500 bed and in the upper bench of the 4500 bed (74.61% db). (2) For lignite samples (on a whole-coal basis), the distributions of two of the HAPs (Pb and Sb) are positively related to ash yield, probably indicating an inorganic affinity for these elements. By using cluster analysis we

  20. Efficacy of interpersonal therapy-group format adapted to post-traumatic stress disorder: an open-label add-on trial.

    Science.gov (United States)

    Campanini, Rosaly F B; Schoedl, Aline F; Pupo, Mariana C; Costa, Ana Clara H; Krupnick, Janice L; Mello, Marcelo F

    2010-01-01

    Post-traumatic stress disorder (PTSD) is a highly prevalent condition, yet available treatments demonstrate only modest efficacy. Exposure therapies, considered by many to be the "gold-standard" therapy for PTSD, are poorly tolerated by many patients and show high attrition. We evaluated interpersonal therapy, in a group format, adapted to PTSD (IPT-G PTSD), as an adjunctive treatment for patients who failed to respond to conventional psychopharmacological treatment. Research participants included 40 patients who sought treatment through a program on violence in the department of psychiatry of Federal University of São Paulo (UNIFESP). They had received conventional psychopharmacological treatment for at least 12 weeks and failed to have an adequate clinical response. After signing an informed consent, approved earlier by the UNIFESP Ethics Review Board, they received a semi-structured diagnostic interview (SCID-I), administered by a trained mental health worker, to confirm the presence of a PTSD diagnosis according to DSM-IV criteria. Other instruments were administered, and patients completed out self-report instruments at baseline, and endpoint to evaluate clinical outcomes. Thirty-three patients completed the trial, but all had at least one second outcome evaluation. There were significant improvements on all measures, with large effect sizes. IPT-G PTSD was effective not only in decreasing symptoms of PTSD, but also in decreasing symptoms of anxiety and depression. It led to significant improvements in social adjustment and quality of life. It was well tolerated and there were few dropouts. Our results are very preliminary; they need further confirmation through randomized controlled clinical trials.

  1. Formative Work to Develop a Tailored HIV Testing Smartphone App for Diverse, At-Risk, HIV-Negative Men Who Have Sex With Men: A Focus Group Study.

    Science.gov (United States)

    Mitchell, Jason W; Torres, Maria Beatriz; Joe, Jennifer; Danh, Thu; Gass, Bobbi; Horvath, Keith J

    2016-11-16

    Although gay, bisexual, and other men who have sex with men (MSM) are disproportionately affected by human immunodeficiency virus (HIV) infection, few test for HIV at regular intervals. Smartphone apps may be an ideal tool to increase regular testing among MSM. However, the success of apps to encourage regular testing among MSM will depend on how frequently the apps are downloaded, whether they continue to be used over months or years, and the degree to which such apps are tailored to the needs of this population. The primary objectives of this study were to answer the following questions. (1) What features and functions of smartphone apps do MSM believe are associated with downloading apps to their mobile phones? (2) What features and functions of smartphone apps are most likely to influence MSM's sustained use of apps over time? (3) What features and functions do MSM prefer in an HIV testing smartphone app? We conducted focus groups (n=7, with a total of 34 participants) with a racially and ethnically diverse group of sexually active HIV-negative MSM (mean age 32 years; 11/34 men, 33%, tested for HIV ≥10 months ago) in the United States in Miami, Florida and Minneapolis, Minnesota. Focus groups were digitally recorded, transcribed verbatim, and deidentified for analysis. We used a constant comparison method (ie, grounded theory coding) to examine and reexamine the themes that emerged from the focus groups. Men reported cost, security, and efficiency as their primary reasons influencing whether they download an app. Usefulness and perceived necessity, as well as peer and posted reviews, affected whether they downloaded and used the app over time. Factors that influenced whether they keep and continue to use an app over time included reliability, ease of use, and frequency of updates. Poor performance and functionality and lack of use were the primary reasons why men would delete an app from their phone. Participants also shared their preferences for an app to

  2. Tracing the transport of colored dissolved organic matter in water masses of the Southern Beaufort Sea: relationship with hydrographic characteristics

    Science.gov (United States)

    Matsuoka, A.; Bricaud, A.; Benner, R.; Para, J.; Sempéré, R.; Prieur, L.; Bélanger, S.; Babin, M.

    2012-03-01

    Light absorption by colored dissolved organic matter (CDOM) [aCDOM(λ)] plays an important role in the heat budget of the Arctic Ocean, contributing to the recent decline in sea ice, as well as in biogeochemical processes. We investigated aCDOM(λ) in the Southern Beaufort Sea where a significant amount of CDOM is delivered by the Mackenzie River. In the surface layer, aCDOM(440) showed a strong and negative correlation with salinity, indicating strong river influence and conservative transport in the river plume. Below the mixed layer, a weak but positive correlation between aCDOM(440) and salinity was observed above the upper halocline, resulting from the effect of removal of CDOM due to brine rejection and lateral intrusion of Pacific summer waters into these layers. In contrast, the relationship was negative in the upper and the lower haloclines, suggesting these waters originated from Arctic coastal waters. DOC concentrations in the surface layer were strongly correlated with aCDOM(440) (r2 = 0.97), suggesting that this value can be estimated in this area, using aCDOM(440) that is retrieved using satellite ocean color data. Implications for estimation of DOC concentrations in surface waters using ocean color remote sensing are discussed.

  3. Wind-sea surface temperature-sea ice relationship in the Chukchi-Beaufort Seas during autumn

    Science.gov (United States)

    Zhang, Jing; Stegall, Steve T.; Zhang, Xiangdong

    2018-03-01

    Dramatic climate changes, especially the largest sea ice retreat during September and October, in the Chukchi-Beaufort Seas could be a consequence of, and further enhance, complex air-ice-sea interactions. To detect these interaction signals, statistical relationships between surface wind speed, sea surface temperature (SST), and sea ice concentration (SIC) were analyzed. The results show a negative correlation between wind speed and SIC. The relationships between wind speed and SST are complicated by the presence of sea ice, with a negative correlation over open water but a positive correlation in sea ice dominated areas. The examination of spatial structures indicates that wind speed tends to increase when approaching the ice edge from open water and the area fully covered by sea ice. The anomalous downward radiation and thermal advection, as well as their regional distribution, play important roles in shaping these relationships, though wind-driven sub-grid scale boundary layer processes may also have contributions. Considering the feedback loop involved in the wind-SST-SIC relationships, climate model experiments would be required to further untangle the underlying complex physical processes.

  4. Habitat use and foraging patterns of molting male Long-tailed Ducks in lagoons of the central Beaufort Sea, Alaska

    Science.gov (United States)

    Flint, Paul L.; Reed, John; Deborah Lacroix,; Richard Lanctot,

    2016-01-01

    From mid-July through September, 10 000 to 30 000 Long-tailed Ducks (Clangula hyemalis) use the lagoon systems of the central Beaufort Sea for remigial molt. Little is known about their foraging behavior and patterns of habitat use during this flightless period. We used radio transmitters to track male Long-tailed Ducks through the molt period from 2000 to 2002 in three lagoons: one adjacent to industrial oil field development and activity and two in areas without industrial activity. We found that an index to time spent foraging generally increased through the molt period. Foraging, habitat use, and home range size showed similar patterns, but those patterns were highly variable among lagoons and across years. Even with continuous daylight during the study period, birds tended to use offshore areas during the day for feeding and roosted in protected nearshore waters at night. We suspect that variability in behaviors associated with foraging, habitat use, and home range size are likely influenced by availability of invertebrate prey. Proximity to oil field activity did not appear to affect foraging behaviors of molting Long-tailed Ducks.

  5. Greater Role of Geostrophic Currents on Ekman Dynamics in the Western Arctic Ocean as a Mechanism for Beaufort Gyre Stabilization

    Science.gov (United States)

    Steele, M.; Zhong, W.; Zhang, J.; Zhao, J.

    2017-12-01

    Seven different methods, with and without including geostrophic currents, were used to explore Ekman dynamics in the western Arctic Ocean for the period 1992-2014. Results show that surface geostrophic currents have been increasing and are much stronger than Ekman layer velocities in recent years (2003-2014) when the oceanic Beaufort Gyre (BG) is spinning up in the region. The new methods that include geostrophic currents result in more realistic Ekman pumping velocities than a previous iterative method that does not consider geostrophic currents and therefore overestimates Ekman pumping velocities by up to 52% in the central area of the BG over the period 2003-2014. When the BG is spinning up as seen in recent years, geostrophic currents become stronger, which tend to modify the ice-ocean stress and to cause an Ekman divergence that counteracts wind-driven Ekman convergence in the Canada Basin. This is a mechanism we have identified to play an important and growing role in stabilizing the Ekman convergence and therefore the BG in recent years. This mechanism may be used to explain three scenarios that describe the interplay of changes in wind forcing, sea ice motion, and geostrophic currents that control the variability of the Ekman dynamics in the central BG during 1992-2014. Results also reveal several upwelling regions in the southern and northern Canada Basin and the Chukchi Abyssal Plain which may plays a significant role in biological processes in these regions.

  6. Long-distance swimming by polar bears (Ursus maritimus) of the southern Beaufort Sea during years of extensive open water

    Science.gov (United States)

    2014-01-01

    Polar bears (Ursus maritimus Phipps, 1774) depend on sea ice for catching marine mammal prey. Recent sea-ice declines have been linked to reductions in body condition, survival, and population size. Reduced foraging opportunity is hypothesized to be the primary cause of sea-ice-linked declines, but the costs of travel through a deteriorated sea-ice environment also may be a factor. We used movement data from 52 adult female polar bears wearing Global Positioning System (GPS) collars, including some with dependent young, to document long-distance swimming (>50 km) by polar bears in the southern Beaufort and Chukchi seas. During 6 years (2004-2009), we identified 50 long-distance swims by 20 bears. Swim duration and distance ranged from 0.7 to 9.7 days (mean = 3.4 days) and 53.7 to 687.1 km (mean = 154.2 km), respectively. Frequency of swimming appeared to increase over the course of the study. We show that adult female polar bears and their cubs are capable of swimming long distances during periods when extensive areas of open water are present. However, long-distance swimming appears to have higher energetic demands than moving over sea ice. Our observations suggest long-distance swimming is a behavioral response to declining summer sea-ice conditions.

  7. Prevalence and spatio-temporal variation of an alopecia syndrome in polar bears (Ursus maritimus) of the southern Beaufort Sea

    Science.gov (United States)

    Atwood, Todd C.; Peacock, Elizabeth; Burek, K.A.; Shearn-Bochsler, Valerie I.; Bodenstein, Barbara L.; Beckmen, Kimberlee B.; Durner, George M.

    2015-01-01

    Alopecia (hair loss) has been observed in several marine mammal species and has potential energetic consequences for sustaining a normal core body temperature, especially for Arctic marine mammals routinely exposed to harsh environmental conditions. Polar bears (Ursus maritimus) rely on a thick layer of adipose tissue and a dense pelage to ameliorate convective heat loss while moving between sea ice and open water. From 1998 to 2012, we observed an alopecia syndrome in polar bears from the southern Beaufort Sea of Alaska that presented as bilaterally asymmetrical loss of guard hairs and thinning of the undercoat around the head, neck, and shoulders, which, in severe cases, was accompanied by exudation and crusted skin lesions. Alopecia was observed in 49 (3.45%) of the bears sampled during 1,421 captures, and the apparent prevalence varied by years with peaks occurring in 1999 (16%) and 2012 (28%). The probability that a bear had alopecia was greatest for subadults and for bears captured in the Prudhoe Bay region, and alopecic individuals had a lower body condition score than unaffected individuals. The cause of the syndrome remains unknown and future work should focus on identifying the causative agent and potential effects on population vital rates.

  8. Demographic and temporal variations in immunity and condition of polar bears (Ursus maritimus) from the southern Beaufort Sea

    Science.gov (United States)

    Neuman-Lee, Lorin; Terletzky, Patricia; Atwood, Todd C.; Gese, Eric; Smith, Geoffrey; Greenfield, Sydney; Pettit, John; French, Susannah

    2017-01-01

    Assessing the health and condition of animals in their natural environment can be problematic. Many physiological metrics, including immunity, are highly influenced by specific context and recent events to which researchers may be unaware. Thus, using a multifaceted physiological approach and a context-specific analysis encompassing multiple time scales can be highly informative. Ecoimmunological tools in particular can provide important indications to the health of animals in the wild. We collected blood and hair samples from free-ranging polar bears (Ursus maritimus) in the southern Beaufort Sea and examined the influence of sex, age, and reproductive status on metrics of immunity, stress, and body condition during 2013–2015. We examined metrics of innate immunity (bactericidal ability and lysis) and stress (hair cortisol, reactive oxygen species, and oxidative barrier), in relation to indices of body condition considered to be short term (urea to creatinine ratio; UC ratio) and long term (storage energy and body mass index). We found the factors of sex, age, and reproductive status of the bear were critical for interpreting different physiological metrics. Additionally, the metrics of body condition were important predictors for stress indicators. Finally, many of these metrics differed between years, illustrating the need to examine populations on a longer time scale. Taken together, this study demonstrates the complex relationship between multiple facets of physiology and how interpretation requires us to examine individuals within a specific context.

  9. Aerial surveys of endangered whales in the Alaskan Chukchi and western Beaufort Seas, 1990. Final report, Oct-Nov 90

    International Nuclear Information System (INIS)

    Moore, S.E.; Clarke, J.T.

    1991-06-01

    In keeping with the National Environmental Policy Act (1969), the Marine Mammal Protection Act (1972) and the Endangered Species Act (1973), the OCS Lands Act Amendments (1978) established a management policy that included studies in OCS lease sale areas to ascertain potential environmental impacts of oil and gas development on OCS marine coastal environments. The Minerals Management Service (MMS) is the agency responsible for these studies and for the leasing of submerged Federal lands. The report summarizes the 1990 investigations of the distribution, abundance, migration, behavior and habitat relationships of endangered whales in the Alaskan Chukchi and western Beaufort Seas (hereafter, study area); 1990 was the second of a three year (1989-91) study. The Bering Sea stock of bowhead whales (Balaena mysticetus) was the principal species studied, with incidental sightings of all other marine mammals routinely recorded. The 1990 season was compromised by circumstances that restricted the availability of the survey aircraft (Grumman Goose, model G21G) to the period 26 October - 7 November; opportunistic surveys were flown in the study area from 3-25 October. In 1990, there were 14 sightings of 19 bowheads from 9-29 October; 5 whales, including 2 calves, were seen north of the study area. One gray whale, 110 belukhas and 53 polar bears were also seen. Over nine survey seasons (1982-90), there were 240 sightings of 520 bowhead whales and 148 sightings of 398 gray whales

  10. Wildlife and wildlife habitat restoration and compensation in the event of an oil spill in the Beaufort Sea

    International Nuclear Information System (INIS)

    Lawrence, M.J.; Davies, S.L.

    1993-01-01

    A procedure for estimating the potential costs of a worst-case scenario for a Beaufort Sea oil spill has been developed by applying assessments of the vulnerability and sensitivity of valued wildlife species to oil, an evaluation of practicability of restoration options, and estimates of the costs of implementing specific measures to aid in the restoration of wildlife species and their habitat. The procedure was developed and tested using valued wildlife species and elements of selected worst-case oil spill scenarios. Proponent use of the procedure in a project-specific application will demand certain information prerequisites, including a project-specific oil spill scenario, an assessment of the potential impacts on wildlife and habitat, and the predicted effectiveness of countermeasures and cleanup. Total compensation costs that account for potential loss of harvest of wildlife in the event of a worst-case oil spill were estimated to be nearly $12.2 million. Recommendations were also made with respect to wildlife and wildlife habitat restoration, as well as with respect to compensation issues. 103 refs., 4 figs., 4 tabs

  11. Distribution and diet of larval and juvenile Arctic cod ( Boreogadus saida) in the shallow Canadian Beaufort Sea

    Science.gov (United States)

    Walkusz, Wojciech; Paulic, Joclyn E.; Williams, William J.; Kwasniewski, Slawomir; Papst, Michael H.

    2011-02-01

    The distribution and diet of larval and juvenile Arctic cod ( Boreogadus saida) were studied during summer 2005 in the coastal Canadian Beaufort Sea. A total of 275 individuals were captured and the highest abundance was observed at station depths of 20-30 m. This corresponds well with the location of the frontal zone where the Mackenzie River plume water and open sea water meet. Diet examinations were performed on 220 Arctic cod, which were found undamaged from sampling. We observed a gradual decrease in prey number per fish and increase in prey size as larvae grew which corresponded to a shift from Rotifera and nauplii towards larger copepodid stages. However, at all sizes, the larvae remain generalists and feed on a broad range of organisms. Environmental changes due to climate warming could have a two-fold impact on fish larvae feeding in the studied region. First, the potential for increased primary production may lead to increased zooplankton production that may impact the feeding and nutrition positively. On the other hand, greater discharge of turbid water from the Mackenzie River may reduce light penetration in the water column that may negatively influence the ability of visual predators to successively forage.

  12. Prevalence and Antibiogram Profiling of Escherichia coli Pathotypes Isolated from the Kat River and the Fort Beaufort Abstraction Water

    Science.gov (United States)

    Nontongana, Nolonwabo; Sibanda, Timothy; Ngwenya, Elvis; Okoh, Anthony I.

    2014-01-01

    Escherichia coli is a widespread bacterium encompassing a variety of strains, ranging from highly pathogenic strains, causing worldwide outbreaks of severe diseases to avirulent, well characterized safe laboratory strains. This study evaluated the prevalence and antibiogram profiles of E. coli pathotypes isolated from the Kat River and Fort Beaufort abstraction water. A total of 171 out of 278 confirmed E. coli isolates were positive for at least one pathogenic determinant and these included enteropathogenic E. coli (6%), enterotoxigenic E. coli (47%), uropathogenic E. coli (2%), neonatal meningitis E. coli (5%), diffusely adherent E. coli (1%) and enterohaemorrhagic E. coli (1%). Interestingly, enteroinvasive and enteroaggregative E. coli were not detected. The phenotypic antibiogram profiles of the isolates revealed that all were resistant to penicillin G, while 98% and 38% of the pathotypes were resistant to ampicillin and trimethoprim-sulphamethoxazole, respectively. About 8% of the isolates were resistant to streptomycin. More than half of the isolates exhibited multiple antibiotic resistance with 44% being resistant to three antibiotics and 8% resistant to four antibiotics. We conclude that the Kat River is a reservoir of potentially virulent antibiotic resistant E. coli strains that can cause serious health risks to humans who drink raw water from this river, or in the case that consumption of treated drinking water coincides with failed drinking water processes. PMID:25119699

  13. Greater Role of Geostrophic Currents in Ekman Dynamics in the Western Arctic Ocean as a Mechanism for Beaufort Gyre Stabilization

    Science.gov (United States)

    Zhong, Wenli; Steele, Michael; Zhang, Jinlun; Zhao, Jinping

    2018-01-01

    Seven different methods, with and without including geostrophic currents, were used to explore Ekman dynamics in the western Arctic Ocean for the period 1992-2014. Results show that surface geostrophic currents have been increasing and are much stronger than Ekman layer velocities in recent years (2003-2014) when the oceanic Beaufort Gyre (BG) is spinning up in the region. The new methods that include geostrophic currents result in more realistic Ekman pumping velocities than a previous iterative method that does not consider geostrophic currents and therefore overestimates Ekman pumping velocities by up to 52% in the central area of the BG over the period 2003-2014. When the BG is spinning up as seen in recent years, geostrophic currents become stronger, which tend to modify the ice-ocean stress and moderate the wind-driven Ekman convergence in the Canada Basin. This is a mechanism we have identified to play an important and growing role in stabilizing the Ekman convergence and therefore the BG in recent years. This mechanism may be used to explain three scenarios that describe the interplay of changes in wind forcing, sea ice motion, and geostrophic currents that control the variability of the Ekman dynamics in the central BG during 1992-2014. Results also reveal several upwelling regions in the southern and northern Canada Basin and the Chukchi Abyssal Plain which may play a significant role in physical and biological processes in these regions.

  14. Tracing the transport of colored dissolved organic matter in water masses of the Southern Beaufort Sea: relationship with hydrographic characteristics

    Directory of Open Access Journals (Sweden)

    A. Matsuoka

    2012-03-01

    Full Text Available Light absorption by colored dissolved organic matter (CDOM [aCDOM(λ] plays an important role in the heat budget of the Arctic Ocean, contributing to the recent decline in sea ice, as well as in biogeochemical processes. We investigated aCDOM(λ in the Southern Beaufort Sea where a significant amount of CDOM is delivered by the Mackenzie River. In the surface layer, aCDOM(440 showed a strong and negative correlation with salinity, indicating strong river influence and conservative transport in the river plume. Below the mixed layer, a weak but positive correlation between aCDOM(440 and salinity was observed above the upper halocline, resulting from the effect of removal of CDOM due to brine rejection and lateral intrusion of Pacific summer waters into these layers. In contrast, the relationship was negative in the upper and the lower haloclines, suggesting these waters originated from Arctic coastal waters. DOC concentrations in the surface layer were strongly correlated with aCDOM(440 (r2 = 0.97, suggesting that this value can be estimated in this area, using aCDOM(440 that is retrieved using satellite ocean color data. Implications for estimation of DOC concentrations in surface waters using ocean color remote sensing are discussed.

  15. Prevalence and Antibiogram Profiling of Escherichia coli Pathotypes Isolated from the Kat River and the Fort Beaufort Abstraction Water

    Directory of Open Access Journals (Sweden)

    Nolonwabo Nontongana

    2014-08-01

    Full Text Available Escherichia coli is a widespread bacterium encompassing a variety of strains, ranging from highly pathogenic strains, causing worldwide outbreaks of severe diseases to avirulent, well characterized safe laboratory strains. This study evaluated the prevalence and antibiogram profiles of E. coli pathotypes isolated from the Kat River and Fort Beaufort abstraction water. A total of 171 out of 278 confirmed E. coli isolates were positive for at least one pathogenic determinant and these included enteropathogenic E. coli (6%, enterotoxigenic E. coli (47%, uropathogenic E. coli (2%, neonatal meningitis E. coli (5%, diffusely adherent E. coli (1% and enterohaemorrhagic E. coli (1%. Interestingly, enteroinvasive and enteroaggregative E. coli were not detected. The phenotypic antibiogram profiles of the isolates revealed that all were resistant to penicillin G, while 98% and 38% of the pathotypes were resistant to ampicillin and trimethoprim-sulphamethoxazole, respectively. About 8% of the isolates were resistant to streptomycin. More than half of the isolates exhibited multiple antibiotic resistance with 44% being resistant to three antibiotics and 8% resistant to four antibiotics. We conclude that the Kat River is a reservoir of potentially virulent antibiotic resistant E. coli strains that can cause serious health risks to humans who drink raw water from this river, or in the case that consumption of treated drinking water coincides with failed drinking water processes.

  16. Prevalence and spatio-temporal variation of an alopecia syndrome in polar bears (Ursus maritimus) of the southern Beaufort Sea.

    Science.gov (United States)

    Atwood, Todd; Peacock, Elizabeth; Burek-Huntington, Kathy; Shearn-Bochsler, Valerie; Bodenstein, Barbara; Beckmen, Kimberlee; Durner, George

    2015-01-01

    Alopecia (hair loss) has been observed in several marine mammal species and has potential energetic consequences for sustaining a normal core body temperature, especially for Arctic marine mammals routinely exposed to harsh environmental conditions. Polar bears (Ursus maritimus) rely on a thick layer of adipose tissue and a dense pelage to ameliorate convective heat loss while moving between sea ice and open water. From 1998 to 2012, we observed an alopecia syndrome in polar bears from the southern Beaufort Sea of Alaska that presented as bilaterally asymmetrical loss of guard hairs and thinning of the undercoat around the head, neck, and shoulders, which, in severe cases, was accompanied by exudation and crusted skin lesions. Alopecia was observed in 49 (3.45%) of the bears sampled during 1,421 captures, and the apparent prevalence varied by years with peaks occurring in 1999 (16%) and 2012 (28%). The probability that a bear had alopecia was greatest for subadults and for bears captured in the Prudhoe Bay region, and alopecic individuals had a lower body condition score than unaffected individuals. The cause of the syndrome remains unknown and future work should focus on identifying the causative agent and potential effects on population vital rates.

  17. Selected Data for Wells and Test Holes Used in Structure-Contour Maps of the Inyan Kara Group, Minnekahta Limestone, Minnelusa Formation, Madison Limestone, and Deadwood Formation in the Black Hills Area, South Dakota

    National Research Council Canada - National Science Library

    Carter, Janet M

    1999-01-01

    This report presents selected data on wells and test holes that were used in the construction of structure-contour maps of selected formations that contain major aquifers in the Black Hills area of western South Dakota...

  18. The Jurassic of Denmark and Greenland: Palynostratigraphy and palaeoenvironment of the Middle Jurassic Sortehat Formation (Neill Klinter Group, Jameson Land, East Greenland

    Directory of Open Access Journals (Sweden)

    Koppelhus, Eva B.

    2003-10-01

    Full Text Available The grey–black mudstones of the Sortehat Formation form part of the Middle Jurassic fill of the Jameson Land Basin in East Greenland. The formation is exposed in the southernmost part of the north–south-trending, Mesozoic rift system in East Greenland that was part of the epeiric seaway between East Greenland and Norway. Sedimentological observations of the Sortehat Formation indicate deposition in an offshore marine setting that was typically low energy and periodically oxygen-deficient but was influenced by storm currents on occasion. Detailed palynological studies of the Sortehat Formation have resulted in the definition of three palynological assemblage zones recognised at four localities, namely Enhjørningen Dal and Pelion (north Jameson Land, the type section at Sortehat (central Jameson Land and Albuen at Neill Klinter along Hurry Inlet(south-east Jameson Land. In stratigraphic order, these zones are termed the Botryococcus Assemblage Zone, the Nannoceratopsis gracilis – Nannoceratopsis senex Assemblage Zone, and the Sentusidinium pelionense Assemblage Zone. They are recognised on the basis of the identification of approximately 110 species of palynomorphs, including 45 species of spores, 30 of pollen, 22 of dinoflagellate cysts, 10 acritarch species, two species of algae, and some fungal spores. An Aalenian – ?Early Bajocian age is suggested for the Sortehat Formation on the basis of thepalynoflora.Interpretation of the palynomorph assemblages suggests that the formation accumulated in a shallow, brackish marine environment. A significant terrestrial input, including the freshwater greenalga Botryococcus, is recorded in the lower part of the formation and interpreted as an allochthonous accumulation in an offshore marine environment related to transgression of a low-lyingcoastal plain. A marked shift in the palynomorph assemblage seen by diversification of marine microplankton above the base of the formation, indicates an

  19. Tonian paleomagnetism of the red beds of Madiyi Formation, lower Banxi Group in South China: implications for pre-Sturtian climate, Rodinia reconstruction and true polar wander

    Science.gov (United States)

    Hanbiao, X.; Zhang, S.; Xiao, Q.; Li, H.; Chang, L.; Fu, H.; Liu, R.

    2017-12-01

    We present a new Tonian paleomagnetic pole from the red beds of ca. 810 Ma Madiyi Formation, lower Banxi Group in the central South China Block (SCB). Detailed thermal demagnetization reveals two distinct magnetic components among the samples. A low temperature component (LTC), removed from almost all the samples below 580°C, yielded a paleopole at 68.0°N, 211.7°E (A95=1.9) that is close to the pole of late Jurassic. The high temperature component (HTC), isolated between 580-690°C, gave a mean direction of D=310.0°, I=57.4°, α95=3.7 (108 samples of 13 sites) after bedding correction, corresponding to a paleomagnetic pole at 47.6°N, 46.7°E (A95=5.6°). The HTC passed a reversal test on 95% and 99% confidence level. Directional distribution of the HTC show significant elongation which may indicate inclination shallowing, and the inclination was corrected to 75.1° using E/I technique, corresponding to a paleolatitude at 60.8±3.4° of research area. The paleopole calculated from the E/I-corrected HTC is at 44.8°N, 80.2°E (A95=3.4°), being significantly distinct from any younger poles of the SCB. This new pole plus existing high quality paleomagnetic poles from the SCB demonstrate that the SCB experienced a polar-equatorial region drifting tendency from 825 Ma to Cambrian. The high-paleolatitude red beds rather than glacial sediments deposited in the SCB, combined with coeval widespread evaporative in other continents, possibly suggest pre-Cryogenian global greenhouse climate. In our reconstruction at 800 Ma, the SCB was placed on the northwest periphery of Rodinia, with its western margin adjacent to the northern India, rather than occupying a central position of Rodinia. The distribution of 825-750 Ma poles of the SCB, East Svalbard, Australia, Laurentia, India along a great arc may be associated with true polar wander around 800 Ma.

  20. Stratigraphic and structural data for the Conasauga Group and the Rome Formation on the Copper Creek fault block near Oak Ridge, Tennessee: preliminary results from test borehole ORNL-JOY No. 2

    International Nuclear Information System (INIS)

    Haase, C.S.; Walls, E.C.; Farmer, C.D.

    1985-06-01

    To resolve long-standing problems with the stratigraphy of the Conasauga Group and the Rome Formation on the Copper Creek fault block near Oak Ridge National Laboratory (ORNL), an 828.5-m-deep test borehole was drilled. Continuous rock core was recovered from the 17.7- to 828.5-m-deep interval; temperature, caliper, neutron, gamma-ray, and acoustic (velocity and televiewer) logs were obtained. The Conasauga Group at the study site is 572.4 m thick and comprises six formations that are - in descending stratigraphic order - Maynardville Limestone (98.8 m), Nolichucky Shale (167.9 m), Maryville Limestone (141.1 m), Rogersville Shale (39.6 m), Rutledge Limestone (30.8 m), and Pumpkin Valley Shale (94.2 m). The formations are lithologically complex, ranging from clastics that consist of shales, mudstones, and siltstones to carbonates that consist of micrites, wackestones, packstones, and conglomerates. The Rome Formation is 188.1 m thick and consists of variably bedded mudstones, siltstones, and sandstones. The Rome Formation thickness represents 88.1 m of relatively undeformed section and 100.0 m of highly deformed, jumbled, and partially repeated section. The bottom of the Rome Formation is marked by a tectonic disconformity that occurs within a 46-m-thick, intensely deformed interval caused by motion along the Copper Creek fault. Results from this study establish the stratigraphy and the lithology of the Conasauga Group and the Rome Formation near ORNL and, for the first time, allow for the unambiguous correlation of cores and geophysical logs from boreholes elsewhere in the ORNL vicinity. 45 refs., 26 figs., 2 tabs

  1. Splitting of 9-iodo-1,7-carborane by potassium hydroxide in butanol with butoxy group substitution for iodine atom when formation of anions of 1-butoxy- and 5-butoxy-nido-7,9-dicarbaundecaborate

    International Nuclear Information System (INIS)

    Zakharkin, L.I.; Ol'shevskaya, V.A.; Guseva, V.V.; Panfilova, S.Yu.

    2000-01-01

    The 9-iodo-1,7-carborane by heating in the potassium hydroxide butanol solution is splitted into the stereoisomeric anions of the nido-7,9-dicarbaundecaborate substituting under the reaction conditions the butoxy-group for iodine atom with formation of anions of the 1-butoxy- and -butoxy-nido-7,9-dicarbaundecaborate [ru

  2. Genetic variation, relatedness, and effective population size of polar bears (Ursus maritimus) in the southern Beaufort Sea, Alaska

    Science.gov (United States)

    Cronin, Matthew A.; Amstrup, Steven C.; Talbot, Sandra L.; Sage, George K.; Amstrup, Kristin S.

    2009-01-01

    Polar bears (Ursus maritimus) are unique among bears in that they are adapted to the Arctic sea ice environment. Genetic data are useful for understanding their evolution and can contribute to management. We assessed parentage and relatedness of polar bears in the southern Beaufort Sea, Alaska, with genetic data and field observations of age, sex, and mother–offspring and sibling relationships. Genotypes at 14 microsatellite DNA loci for 226 bears indicate that genetic variation is comparable to other populations of polar bears with mean number of alleles per locus of 7.9 and observed and expected heterozygosity of 0.71. The genetic data verified 60 field-identified mother–offspring pairs and identified 10 additional mother–cub pairs and 48 father–offspring pairs. The entire sample of related and unrelated bears had a mean pairwise relatedness index (rxy) of approximately zero, parent–offspring and siblings had rxy of approximately 0.5, and 5.2% of the samples had rxy values within the range expected for parent-offspring. Effective population size (Ne= 277) and the ratio of Ne to total population size (Ne/N = 0.182) were estimated from the numbers of reproducing males and females. Ne estimates with genetic methods gave variable results. Our results verify and expand field data on reproduction by females and provide new data on reproduction by males and estimates of relatedness and Ne in a polar bear population.

  3. Robust wavebuoys for the marginal ice zone: Experiences from a large persistent array in the Beaufort Sea

    Directory of Open Access Journals (Sweden)

    Martin J. Doble

    2017-08-01

    Full Text Available An array of novel directional wavebuoys was designed and deployed into the Beaufort Sea ice cover in March 2014, as part of the Office of Naval Research 'Marginal Ice Zone' experiment. The buoys were designed to drift with the ice throughout the year and monitor the expected breakup and retreat of the ice cover, forced by waves travelling into the ice from open water. Buoys were deployed from fast-and-light air-supported ice camps, based out of Sachs Harbour on Canada’s Banks Island, and drifted westwards with the sea ice over the course of spring, summer and autumn, as the ice melted, broke up and finally re-froze. The buoys transmitted heave, roll and pitch timeseries at 1 Hz sample frequency over the course of up to eight months, surviving both convergent ice dynamics and significant waves-in-ice events. Twelve of the 19 buoys survived until their batteries were finally exhausted during freeze-up in late October/November. Ice impact was found to have contaminated a significant proportion of the Kalman-filter-derived heave records, and these bad records were removed with reference to raw x/y/z accelerations. The quality of magnetometer-derived buoy headings at the very high magnetic field inclinations close to the magnetic pole was found to be generally acceptable, except in the case of four buoys which had probably suffered rough handling during transport to the ice. In general, these new buoys performed as expected, though vigilance as to the veracity of the output is required.

  4. Genetic variation, relatedness, and effective population size of polar bears (Ursus maritimus) in the southern Beaufort Sea, Alaska.

    Science.gov (United States)

    Cronin, Matthew A; Amstrup, Steven C; Talbot, Sandra L; Sage, George K; Amstrup, Kristin S

    2009-01-01

    Polar bears (Ursus maritimus) are unique among bears in that they are adapted to the Arctic sea ice environment. Genetic data are useful for understanding their evolution and can contribute to management. We assessed parentage and relatedness of polar bears in the southern Beaufort Sea, Alaska, with genetic data and field observations of age, sex, and mother-offspring and sibling relationships. Genotypes at 14 microsatellite DNA loci for 226 bears indicate that genetic variation is comparable to other populations of polar bears with mean number of alleles per locus of 7.9 and observed and expected heterozygosity of 0.71. The genetic data verified 60 field-identified mother-offspring pairs and identified 10 additional mother-cub pairs and 48 father-offspring pairs. The entire sample of related and unrelated bears had a mean pairwise relatedness index (r(xy)) of approximately zero, parent-offspring and siblings had r(xy) of approximately 0.5, and 5.2% of the samples had r(xy) values within the range expected for parent-offspring. Effective population size (N(e) = 277) and the ratio of N(e) to total population size (N(e)/N = 0.182) were estimated from the numbers of reproducing males and females. N(e) estimates with genetic methods gave variable results. Our results verify and expand field data on reproduction by females and provide new data on reproduction by males and estimates of relatedness and N(e) in a polar bear population.

  5. Individual-level movement bias leads to the formation of higher-order social structure in a mobile group of baboons.

    Science.gov (United States)

    Bonnell, Tyler R; Clarke, Parry M; Henzi, S Peter; Barrett, Louise

    2017-07-01

    In mobile social groups, influence patterns driving group movement can vary between democratic and despotic. The arrival at any single pattern of influence is thought to be underpinned by both environmental factors and group composition. To identify the specific patterns of influence driving travel decision-making in a chacma baboon troop, we used spatially explicit data to extract patterns of individual movement bias. We scaled these estimates of individual-level bias to the level of the group by constructing an influence network and assessing its emergent structural properties. Our results indicate that there is heterogeneity in movement bias: individual animals respond consistently to particular group members, and higher-ranking animals are more likely to influence the movement of others. This heterogeneity resulted in a group-level network structure that consisted of a single core and two outer shells. Here, the presence of a core suggests that a set of highly interdependent animals drove routine group movements. These results suggest that heterogeneity at the individual level can lead to group-level influence structures, and that movement patterns in mobile social groups can add to the exploration of both how these structures develop (i.e. mechanistic aspects) and what consequences they have for individual- and group-level outcomes (i.e. functional aspects).

  6. Production and testing of the ENEA-Bologna VITJEFF32.BOLIB (JEFF-3.2) multi-group (199 n + 42 γ) cross section library in AMPX format for nuclear fission applications

    Science.gov (United States)

    Pescarini, Massimo; Orsi, Roberto; Frisoni, Manuela

    2017-09-01

    The ENEA-Bologna Nuclear Data Group produced the VITJEFF32.BOLIB multi-group coupled neutron/photon (199 n + 42 γ) cross section library in AMPX format, based on the OECD-NEA Data Bank JEFF-3.2 evaluated nuclear data library. VITJEFF32.BOLIB was conceived for nuclear fission applications as European counterpart of the ORNL VITAMIN-B7 similar library (ENDF/B-VII.0 data). VITJEFF32.BOLIB has the same neutron and photon energy group structure as the former ORNL VITAMIN-B6 reference library (ENDF/B-VI.3 data) and was produced using similar data processing methodologies, based on the LANL NJOY-2012.53 nuclear data processing system for the generation of the nuclide cross section data files in GENDF format. Then the ENEA-Bologna 2007 Revision of the ORNL SCAMPI nuclear data processing system was used for the conversion into the AMPX format. VITJEFF32.BOLIB contains processed cross section data files for 190 nuclides, obtained through the Bondarenko (f-factor) method for the treatment of neutron resonance self-shielding and temperature effects. Collapsed working libraries of self-shielded cross sections in FIDO-ANISN format, used by the deterministic transport codes of the ORNL DOORS system, can be generated from VITJEFF32.BOLIB through the cited SCAMPI version. This paper describes the methodology and specifications of the data processing performed and presents some results of the VITJEFF32.BOLIB validation.

  7. Production and testing of the ENEA-Bologna VITJEFF32.BOLIB (JEFF-3.2 multi-group (199 n + 42 γ cross section library in AMPX format for nuclear fission applications

    Directory of Open Access Journals (Sweden)

    Pescarini Massimo

    2017-01-01

    Full Text Available The ENEA-Bologna Nuclear Data Group produced the VITJEFF32.BOLIB multi-group coupled neutron/photon (199 n + 42 γ cross section library in AMPX format, based on the OECD-NEA Data Bank JEFF-3.2 evaluated nuclear data library. VITJEFF32.BOLIB was conceived for nuclear fission applications as European counterpart of the ORNL VITAMIN-B7 similar library (ENDF/B-VII.0 data. VITJEFF32.BOLIB has the same neutron and photon energy group structure as the former ORNL VITAMIN-B6 reference library (ENDF/B-VI.3 data and was produced using similar data processing methodologies, based on the LANL NJOY-2012.53 nuclear data processing system for the generation of the nuclide cross section data files in GENDF format. Then the ENEA-Bologna 2007 Revision of the ORNL SCAMPI nuclear data processing system was used for the conversion into the AMPX format. VITJEFF32.BOLIB contains processed cross section data files for 190 nuclides, obtained through the Bondarenko (f-factor method for the treatment of neutron resonance self-shielding and temperature effects. Collapsed working libraries of self-shielded cross sections in FIDO-ANISN format, used by the deterministic transport codes of the ORNL DOORS system, can be generated from VITJEFF32.BOLIB through the cited SCAMPI version. This paper describes the methodology and specifications of the data processing performed and presents some results of the VITJEFF32.BOLIB validation.

  8. U-Pb (SHRIMP II) Age of zircons from ash tuffs of the upper vendian Chernyi Kamen formation (Sylvitsa group, Middle Urals)

    International Nuclear Information System (INIS)

    Ronkin, Yu.L.; Grazhdankin, D.V.; Maslov, A.V.; Mizens, G.A.; Matukov, D.I.; Krupenin, M.T.; Petrov, G.A.; Lepikhina, O.P.; Kornilova, A.Yu.

    2006-01-01

    To make more precise the model of correlation of the Middle Urals western slope upper vendian layers with the White Sea remote layers one carried out the SHRIMP-II procedure base U-Pb-dating of the volcanogenic zircons from the ash tuffs and of the volcanogenic zircon enclosing argillites of the Middle Urals Chernyi Kamen formation. The obtained age value of the studied zircons equal to 557+-13 million years is in line with the geological data [ru

  9. Food habits of Arctic staghorn sculpin (Gymnocanthus tricuspis) and shorthorn sculpin (Myoxocephalus scorpius) in the northeastern Chukchi and western Beaufort Seas

    Science.gov (United States)

    Gray, Benjamin P.; Norcross, Brenda L.; Beaudreau, Anne H.; Blanchard, Arny L.; Seitz, Andrew C.

    2017-01-01

    Arctic staghorn sculpin (Gymnocanthus tricuspis) and shorthorn sculpin (Myoxocephalus scorpius) belong to Cottidae, the second most abundant fish family in the western Arctic. Although considered important in food webs, little is known about their food habits throughout this region. To address this knowledge gap, we examined and compared the diets of 515 Arctic staghorn sculpin and 422 shorthorn sculpin using stomachs collected over three summers in the northeastern Chukchi Sea (2010-2012) and one summer in the western Beaufort Sea (2011). We used permutational multivariate analysis of variance (PERMANOVA) and non-metric multidimensional scaling (nMDS) to compare sculpin diets between regions and selected size classes. Differences in mouth morphologies and predator size versus prey size relationships were examined using regression techniques. Arctic staghorn sculpin and shorthorn sculpin diet compositions differed greatly throughout the Chukchi and Beaufort Seas. Regardless of body size, the smaller-mouthed Arctic staghorn sculpin consumed mostly benthic amphipods and polychaetes, whereas the larger-mouthed shorthorn sculpin shifted from a diet composed of benthic and pelagic macroinvertebrates as smaller individuals to shrimps and fish prey as larger individuals. Within shared habitats, the sculpins appear to partition prey, either by taxa or size, in a manner that suggests no substantial overlap occurs between species. This study increases knowledge of sculpin feeding ecology in the western Arctic and offers regional, quantitative diet information that could support current and future food web modeling efforts.

  10. Group play

    DEFF Research Database (Denmark)

    Tychsen, Anders; Hitchens, Michael; Brolund, Thea

    2008-01-01

    Role-playing games (RPGs) are a well-known game form, existing in a number of formats, including tabletop, live action, and various digital forms. Despite their popularity, empirical studies of these games are relatively rare. In particular there have been few examinations of the effects of the v......Role-playing games (RPGs) are a well-known game form, existing in a number of formats, including tabletop, live action, and various digital forms. Despite their popularity, empirical studies of these games are relatively rare. In particular there have been few examinations of the effects...... of the various formats used by RPGs on the gaming experience. This article presents the results of an empirical study, examining how multi-player tabletop RPGs are affected as they are ported to the digital medium. Issues examined include the use of disposition assessments to predict play experience, the effect...... of group dynamics, the influence of the fictional game characters and the comparative play experience between the two formats. The results indicate that group dynamics and the relationship between the players and their digital characters, are integral to the quality of the gaming experience in multiplayer...

  11. Multivariate benthic ecosystem functioning in the Arctic – benthic fluxes explained by environmental parameters in the southeastern Beaufort Sea

    Directory of Open Access Journals (Sweden)

    H. Link

    2013-09-01

    Full Text Available The effects of climate change on Arctic marine ecosystems and their biogeochemical cycles are difficult to predict given the complex physical, biological and chemical interactions among the ecosystem components. We studied benthic biogeochemical fluxes in the Arctic and the influence of short-term (seasonal to annual, long-term (annual to decadal and other environmental variability on their spatial distribution to provide a baseline for estimates of the impact of future changes. In summer 2009, we measured fluxes of dissolved oxygen, nitrate, nitrite, ammonia, soluble reactive phosphate and silicic acid at the sediment–water interface at eight sites in the southeastern Beaufort Sea at water depths from 45 to 580 m. The spatial pattern of the measured benthic boundary fluxes was heterogeneous. Multivariate analysis of flux data showed that no single or reduced combination of fluxes could explain the majority of spatial variation, indicating that oxygen flux is not representative of other nutrient sink–source dynamics. We tested the influence of eight environmental parameters on single benthic fluxes. Short-term environmental parameters (sinking flux of particulate organic carbon above the bottom, sediment surface Chl a were most important for explaining oxygen, ammonium and nitrate fluxes. Long-term parameters (porosity, surface manganese and iron concentration, bottom water oxygen concentrations together with δ13Corg signature explained most of the spatial variation in phosphate, nitrate and nitrite fluxes. Variation in pigments at the sediment surface was most important to explain variation in fluxes of silicic acid. In a model including all fluxes synchronously, the overall spatial distribution could be best explained (57% by the combination of sediment Chl a, phaeopigments, δ13Corg, surficial manganese and bottom water oxygen concentration. We conclude that it is necessary to consider long-term environmental variability along with

  12. Storage of radioactive wastes in geological formations. Technical criteria for site selection. Report by the work-group chaired by Professor Goguel

    International Nuclear Information System (INIS)

    Goguel, Jean; Candes, Pierre; Izabel, Cecile; Autran, Albert; Barthoux, Alain; Baudin, Guy; Devillers, Christian; Habib, Pierre; Lafuma, Jacques; Lefevre, Jean; Peaudecerf, Pierre; Pradel, Jacques; Salle, Claude; Treuil, Michel; Lebrun, Patrick; Tissier, Marie-Solange

    1985-06-01

    This document is the result of a prospective mission on the long term storage of radioactive wastes containing long-period emitters (wastes of B and C categories), and notably on a definitive storage in deep continental geological formations. After a presentation of hypotheses (brief description of the storage concept, main safety principles, objectives in terms of radiological safety, safety options, time-related considerations), the authors addressed the following issues: safety before closing during the exploitation period, and safety after closure (after backfilling and sealing of all underground cavities). For the first issue, they discuss the impacts of works on safety and thermal effects during exploitation. For the second issue, they discuss the site natural hydro-geological context, the disturbances brought by the storage (access of water to the storage, and return of water into the biosphere), and the influence of external factors (geological phenomena, human intrusion). Then, the authors make recommendations regarding reconnaissance programs and studies for the selection and qualification of a site. They finally propose technical criteria and main recommendations for site selection. Appendices propose a list of hearings, a presentation of the storage concept, a report on the impact of works, a report on the presence of mineralisation in granite massifs, reports on radiological consequences of intrusions in salt formations and in granite massif containing storage of radioactive wastes or vitrified wastes, a report on the characterization of unsteady parts of the French continental construction, a presentation of the evolution of climate and icings, and a study of seismic movements in the case of deep storages

  13. In situ formation of adhesive hydrogels based on PL with laterally grafted catechol groups and their bonding efficacy to wet organic substrates.

    Science.gov (United States)

    Ye, Mingming; Jiang, Rui; Zhao, Jin; Zhang, Juntao; Yuan, Xubo; Yuan, Xiaoyan

    2015-12-01

    Adhesives with catechol moieties have been widely investigated in recent years. However, actually how much catechol groups for these mussel bio-inspired adhesives, especially in their natural form under physiological condition, is appropriate to bond with organic substrates has not been studied intensively. This study blends ε-polylysine (PL), featuring laterally grafted catechols under physiological conditions (pH 7.4), with oxidized dextran to form a hydrogel in situ via the Schiff base without introducing small cytotoxic molecules as crosslinking agents. It finds that the amount of catechol groups imposes an obvious influence on gelation time, swelling behavior, and hydrogel morphology. Both the storage modulus and adhesion strength are found to increase first and decrease afterwards with an increase of pendent catechol content. Furthermore, catechol hydrogen interactions and the decrease in the crosslink density derived from the decrease of amino groups on PL are simultaneously found to affect the storage modulus. Meanwhile, multiple hydrogen-bonding interactions of catechol with amino, hydroxyl, and carboxyl groups, which are in abundance on the surface of tissue, are mainly found to provide an adhesive force. The study finds that with more catechol, there is a greater chance that the cohesive force will weaken, making the entire adhesion strength of the hydrogel decrease. Using a cytotoxicity test, the nontoxicity of the hydrogel towards the growth of L929 cells is proven, indicating that hydrogels have potential applications in soft tissue repair under natural physiological conditions.

  14. Decomposition of group-velocity-locked-vector-dissipative solitons and formation of the high-order soliton structure by the product of their recombination.

    Science.gov (United States)

    Wang, Xuan; Li, Lei; Geng, Ying; Wang, Hanxiao; Su, Lei; Zhao, Luming

    2018-02-01

    By using a polarization manipulation and projection system, we numerically decomposed the group-velocity-locked-vector-dissipative solitons (GVLVDSs) from a normal dispersion fiber laser and studied the combination of the projections of the phase-modulated components of the GVLVDS through a polarization beam splitter. Pulses with a structure similar to a high-order vector soliton could be obtained, which could be considered as a pseudo-high-order GVLVDS. It is found that, although GVLVDSs are intrinsically different from group-velocity-locked-vector solitons generated in fiber lasers operated in the anomalous dispersion regime, similar characteristics for the generation of pseudo-high-order GVLVDS are obtained. However, pulse chirp plays a significant role on the generation of pseudo-high-order GVLVDS.

  15. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, Coulometer for DIC measurement and other instruments from the ODEN in the Arctic Ocean, Beaufort Sea and Bering Sea from 2005-08-19 to 2005-09-25 (NODC Accession 0108129)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0108129 includes chemical, discrete sample, physical and profile data collected from ODEN in the Arctic Ocean, Beaufort Sea and Bering Sea from...

  16. Dissolved inorganic carbon, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, PAR Sensor and other instruments from HEALY in the Arctic Ocean, Beaufort Sea and Bering Sea from 2002-05-05 to 2002-06-15 (NODC Accession 0113952)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0113952 includes biological, chemical, discrete sample, optical, physical and profile data collected from HEALY in the Arctic Ocean, Beaufort Sea and...

  17. Dissolved inorganic carbon, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, PAR Sensor and other instruments from HEALY in the Arctic Ocean, Beaufort Sea and Bering Sea from 2004-05-15 to 2004-06-23 (NODC Accession 0115592)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0115592 includes biological, chemical, discrete sample, optical, physical and profile data collected from HEALY in the Arctic Ocean, Beaufort Sea and...

  18. Temperature, salinity and other variables collected from discrete sample and profile observations using CTD, PAR Sensor and other instruments from the NATHANIEL B. PALMER in the Arctic Ocean, Beaufort Sea and Bering Sea from 2003-07-05 to 2003-08-20 (NODC Accession 0116064)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0116064 includes biological, chemical, discrete sample, physical and profile data collected from NATHANIEL B. PALMER in the Arctic Ocean, Beaufort Sea...

  19. Dissolved inorganic carbon, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from HEALY in the Arctic Ocean, Beaufort Sea and Bering Sea from 2004-07-18 to 2004-08-26 (NODC Accession 0115707)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0115707 includes biological, chemical, discrete sample, optical, physical and profile data collected from HEALY in the Arctic Ocean, Beaufort Sea and...

  20. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using Alkalinity titrator, CTD and other instruments from JAKOV SMIRNITSKIY in the Beaufort Sea, East Siberian Sea and others from 2008-08-15 to 2008-09-16 (NODC Accession 0108368)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0108368 includes chemical, discrete sample, physical and profile data collected from JAKOV SMIRNITSKIY in the Beaufort Sea, East Siberian Sea, Kara...

  1. Dissolved inorganic carbon, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from HEALY in the Arctic Ocean, Beaufort Sea and Bering Sea from 2002-07-18 to 2002-08-21 (NODC Accession 0113953)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0113953 includes biological, chemical, discrete sample, physical and profile data collected from HEALY in the Arctic Ocean, Beaufort Sea and Bering...

  2. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from underway - surface observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from the XUE LONG in the Arctic Ocean, Beaufort Sea and Bering Sea from 2008-07-30 to 2008-09-11 (NODC Accession 0109932)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0109932 includes chemical, meteorological, physical and underway - surface data collected from XUE LONG in the Arctic Ocean, Beaufort Sea and Bering...

  3. Dissolved inorganic carbon, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the LOUIS S. ST. LAURENT in the Beaufort Sea and Northwest Passage from 1997-08-31 to 1997-09-16 (NODC Accession 0116061)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0116061 includes chemical, discrete sample, physical and profile data collected from LOUIS S. ST. LAURENT in the Beaufort Sea and Northwest Passage...

  4. Dissolved inorganic carbon, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the LOUIS S. ST. LAURENT in the Arctic Ocean and Beaufort Sea from 1997-09-24 to 1997-10-15 (NODC Accession 0113984)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0113984 includes chemical, discrete sample, physical and profile data collected from LOUIS S. ST. LAURENT in the Arctic Ocean and Beaufort Sea from...

  5. Dissolved inorganic carbon, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the LOUIS S. ST. LAURENT in the Arctic Ocean, Beaufort Sea and North Greenland Sea from 1994-07-24 to 1994-09-01 (NODC Accession 0113983)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0113983 includes chemical, discrete sample, physical and profile data collected from LOUIS S. ST. LAURENT in the Arctic Ocean, Beaufort Sea and North...

  6. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, Coulometer for DIC measurement and other instruments from MIRAI in the Beaufort Sea and Bering Sea from 2006-08-21 to 2006-09-29 (NODC Accession 0112268)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0112268 includes chemical, discrete sample, optical, physical and profile data collected from MIRAI in the Beaufort Sea and Bering Sea from 2006-08-21...

  7. Temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the TYRO in the Arctic Ocean and Beaufort Sea from 1996-09-13 to 1996-10-28 (NODC Accession 0116717)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0116717 includes chemical, discrete sample, physical and profile data collected from TYRO in the Arctic Ocean and Beaufort Sea from 1996-09-13 to...

  8. Dissolved inorganic carbon, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, Coulometer for DIC measurement and other instruments from the MIRAI in the Arctic Ocean and Beaufort Sea from 1999-09-11 to 1999-10-05 (NODC Accession 0112350)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0112350 includes chemical, discrete sample, physical and profile data collected from MIRAI in the Arctic Ocean and Beaufort Sea from 1999-09-11 to...

  9. Dissolved inorganic carbon, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, Coulometer for DIC measurement and other instruments from the MIRAI in the Arctic Ocean, Beaufort Sea and others from 2002-08-22 to 2002-10-10 (NODC Accession 0112355)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0112355 includes biological, chemical, discrete sample, physical and profile data collected from MIRAI in the Arctic Ocean, Beaufort Sea, Bering Sea...

  10. Alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, Coulometer for DIC measurement and other instruments from MIRAI in the Arctic Ocean and Beaufort Sea from 2004-09-01 to 2004-10-13 (NODC Accession 0112357)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0112357 includes biological, chemical, discrete sample, physical and profile data collected from MIRAI in the Arctic Ocean and Beaufort Sea from...

  11. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from HEALY in the Arctic Ocean, Beaufort Sea and others from 2014-05-05 to 2014-08-30 (NCEI Accession 0144350)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0144350 includes Surface underway data collected from HEALY in the Arctic Ocean, Beaufort Sea, Bering Sea, Coastal Waters of SE Alaska, Gulf of...

  12. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from HEALY in the Arctic Ocean, Beaufort Sea and others from 2013-08-06 to 2013-10-29 (NCEI Accession 0144346)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0144346 includes Surface underway data collected from HEALY in the Arctic Ocean, Beaufort Sea, Bering Sea and Northwest Passage from 2013-08-06 to...

  13. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer and other instruments from HEALY in the Arctic Ocean, Beaufort Sea and others from 2015-08-09 to 2015-10-12 (NCEI Accession 0157049)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0157049 includes Surface underway, chemical, meteorological and physical data collected from HEALY in the Arctic Ocean, Beaufort Sea, Bering Sea,...

  14. Partial pressure (or fugacity) of carbon dioxide, salinity and SEA SURFACE TEMPERATURE collected from underway - surface observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from the NATHANIEL B. PALMER in the Arctic Ocean, Beaufort Sea and others from 1994-11-04 to 2012-08-31 (NODC Accession 0083189)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0083189 includes chemical, physical and underway - surface data collected from NATHANIEL B. PALMER in the Arctic Ocean, Beaufort Sea, Bering Sea,...

  15. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from Marcus G. Langseth in the Arctic Ocean, Beaufort Sea and others from 2011-04-13 to 2011-12-28 (NCEI Accession 0144305)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0144305 includes Surface underway data collected from Marcus G. Langseth in the Arctic Ocean, Beaufort Sea, Bering Sea, Gulf of Alaska, Hawaiian...

  16. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from HEALY in the Arctic Ocean, Beaufort Sea and others from 2015-07-14 to 2015-10-28 (NCEI Accession 0144530)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0144530 includes Surface underway data collected from HEALY in the Arctic Ocean, Beaufort Sea, Bering Sea, Coastal Waters of SE Alaska, Gulf of Alaska...

  17. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from HEALY in the Arctic Ocean, Beaufort Sea and others from 2012-08-01 to 2012-10-24 (NCEI Accession 0144338)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0144338 includes Surface underway data collected from HEALY in the Arctic Ocean, Beaufort Sea, Bering Sea, Coastal Waters of SE Alaska and North...

  18. Partial pressure (or fugacity) of carbon dioxide, salinity and SEA SURFACE TEMPERATURE collected from underway - surface observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from the HEALY in the Arctic Ocean, Beaufort Sea and others from 2011-05-17 to 2012-10-26 (NODC Accession 0083197)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0083197 includes chemical, physical and underway - surface data collected from HEALY in the Arctic Ocean, Beaufort Sea, Bering Sea, Coastal Waters of...

  19. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from NATHANIEL B. PALMER in the Arctic Ocean, Beaufort Sea and others from 2003-01-05 to 2004-01-15 (NCEI Accession 0157387)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0157387 includes Surface underway, chemical, meteorological and physical data collected from NATHANIEL B. PALMER in the Arctic Ocean, Beaufort Sea,...

  20. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer and other instruments from Sikuliaq in the Arctic Ocean, Beaufort Sea and Bering Sea from 2015-08-13 to 2015-09-02 (NCEI Accession 0157261)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0157261 includes Surface underway, chemical, meteorological and physical data collected from Sikuliaq in the Arctic Ocean, Beaufort Sea and Bering Sea...

  1. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from HEALY in the Arctic Ocean, Beaufort Sea and others from 2011-05-27 to 2011-12-16 (NCEI Accession 0144345)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0144345 includes Surface underway data collected from HEALY in the Arctic Ocean, Beaufort Sea, Bering Sea, Coastal Waters of SE Alaska, Gulf of...

  2. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer and other instruments from NOAA Ship RONALD H. BROWN in the Arctic Ocean, Beaufort Sea and others from 2015-01-15 to 2015-12-18 (NCEI Accession 0157252)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0157252 includes Surface underway, chemical, meteorological and physical data collected from NOAA Ship RONALD H. BROWN in the Arctic Ocean, Beaufort...

  3. Dissolved inorganic carbon, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, Coulometer for DIC measurement and other instruments from the MIRAI in the Arctic Ocean, Beaufort Sea and Bering Sea from 2000-08-03 to 2000-10-13 (NODC Accession 0112352)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0112352 includes chemical, discrete sample, physical and profile data collected from MIRAI in the Arctic Ocean, Beaufort Sea and Bering Sea from...

  4. Partial pressure (or fugacity) of carbon dioxide, salinity and SEA SURFACE TEMPERATURE collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from Marcus G. Langseth in the Arctic Ocean, Beaufort Sea and others from 2010-05-07 to 2013-06-25 (NODC Accession 0109901)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0109901 includes Surface underway data collected from Marcus G. Langseth in the Arctic Ocean, Beaufort Sea, Bering Sea, Caribbean Sea, Cordell Bank...

  5. Atomic geometry and STM simulations of a TiO.sub.2./sub.(110) surface upon formation of an oxygen vacancy and hydroxyl group

    Czech Academy of Sciences Publication Activity Database

    Mutombo, Pingo; Kiss, A.M.; Berkó, A.; Cháb, Vladimír

    2008-01-01

    Roč. 16, - (2008), 025007/1-025007/9 ISSN 0965-0393 R&D Projects: GA AV ČR IAA1010413 Grant - others:MŠMT(CZ) 9/2004 KONTAKT Institutional research plan: CEZ:AV0Z10100521 Source of funding: V - iné verejné zdroje Keywords : vacance * Oxygen * OH group * STM Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.388, year: 2008

  6. The "Molecular and cell Biology" program of the Presidium of the Russian Academyof sciences as an effective format for the support of promising scientific research groups

    OpenAIRE

    Sychev, V.

    2010-01-01

    There are various ways to finance science in Russia, both governmental and private. Financial support can range from tens of thousands of rubles up to several million in stipends and grants. One of the questions most often addressed to the heads of agencies or funds is about the level of transparency and objectivity when selecting groups which receive financial support. Few well-known financing organizations have avoided criticism regarding this issue. Nevertheless, there is one scientific fi...

  7. Petroleum systems and geologic assessment of undiscovered oil and gas, Cotton Valley group and Travis Peak-Hosston formations, East Texas basin and Louisiana-Mississippi salt basins provinces of the northern Gulf Coast region. Chapters 1-7.

    Science.gov (United States)

    ,

    2006-01-01

    The purpose of the U.S. Geological Survey's (USGS) National Oil and Gas Assessment is to develop geologically based hypotheses regarding the potential for additions to oil and gas reserves in priority areas of the United States. The USGS recently completed an assessment of undiscovered oil and gas potential of the Cotton Valley Group and Travis Peak and Hosston Formations in the East Texas Basin and Louisiana-Mississippi Salt Basins Provinces in the Gulf Coast Region (USGS Provinces 5048 and 5049). The Cotton Valley Group and Travis Peak and Hosston Formations are important because of their potential for natural gas resources. This assessment is based on geologic principles and uses the total petroleum system concept. The geologic elements of a total petroleum system include hydrocarbon source rocks (source rock maturation, hydrocarbon generation and migration), reservoir rocks (sequence stratigraphy and petrophysical properties), and hydrocarbon traps (trap formation and timing). The USGS used this geologic framework to define one total petroleum system and eight assessment units. Seven assessment units were quantitatively assessed for undiscovered oil and gas resources.

  8. Aerial Surveys of Endangered Whales in the Northern Bering, Eastern Chukchi, and Alaskan Beaufort Seas, 1984: with a Six Year Review, 1979-1984.

    Science.gov (United States)

    1985-06-01

    I- * I 4 ?2 7- /’PT L0~ *70 BATRIS. K ERSCHIE I 158 158 154 152 1SO 148 146 144 142 140 138 9EAUFORT SEA 72 D 71 70 - -BRE i" isI ISO 154 152... ISO 146 146 144 142 140 136 Figure 19. (Continued). 51 Sp In October, 99 bowheads were sighted in the Beaufort Sea along and seaward of the 20-m isobath...04501T 51% 2% 43% 3% 27001 09001 27001 09001 21% 19% 4% 22501 9% 13501 22501 4% 3% 13501 18001 18001 n 47, R :226 0T n - 10, R 211 IT z2740,pɘD01 z -39.86

  9. UV/PAR radiation and DOM properties in surface coastal waters of the Canadian shelf of the Beaufort Sea during summer 2009

    Directory of Open Access Journals (Sweden)

    J. Para

    2013-04-01

    Full Text Available Surface waters from the Beaufort Sea in the Arctic Ocean were evaluated for dissolved organic carbon (DOC, and optical characteristics including UV (ultraviolet radiation and PAR (photosynthetically active radiation diffuse attenuation (Kd, and chromophoric and fluorescent dissolved organic matter (CDOM and FDOM as part of the MALINA field campaign (30 July to 27 August. Spectral absorption coefficients (aCDOM (350 nm (m−1 were significantly correlated to both diffuse attenuation coefficients (Kd in the UV-A and UV-B and to DOC concentrations. This indicates CDOM as the dominant attenuator of both UV and PAR solar radiation and suggests its use as an optical proxy for DOC concentrations in this region. While the Mackenzie input is the main driver of CDOM dynamics in low salinity waters, locally, primary production can create significant increases in CDOM. Extrapolating CDOM to DOC relationships, we estimate that ∼16% of the DOC in the Mackenzie River does not absorb radiation at 350 nm. The discharges of DOC and its chromophoric subset (CDOM by the Mackenzie River during the MALINA cruise are estimated as ∼0.22 TgC and 0.18 TgC, respectively. Three dissolved fluorescent components (C1–C3 were identified by fluorescence excitation/emission matrix spectroscopy (EEMS and parallel factor (PARAFAC analysis. Our results showed an aquatic dissolved organic matter (DOM component (C1, probably produced in the numerous lakes of the watershed, that co-dominated with a terrestrial humic-like component (C2 in the Mackenzie Delta Sector. This aquatic DOM could partially explain the high CDOM spectral slopes observed in the Beaufort Sea.

  10. UV/PAR radiation and DOM properties in surface coastal waters of the Canadian shelf of the Beaufort Sea during summer 2009

    Science.gov (United States)

    Para, J.; Charrière, B.; Matsuoka, A.; Miller, W. L.; Rontani, J. F.; Sempéré, R.

    2013-04-01

    Surface waters from the Beaufort Sea in the Arctic Ocean were evaluated for dissolved organic carbon (DOC), and optical characteristics including UV (ultraviolet) radiation and PAR (photosynthetically active radiation) diffuse attenuation (Kd), and chromophoric and fluorescent dissolved organic matter (CDOM and FDOM) as part of the MALINA field campaign (30 July to 27 August). Spectral absorption coefficients (aCDOM (350 nm) (m-1)) were significantly correlated to both diffuse attenuation coefficients (Kd) in the UV-A and UV-B and to DOC concentrations. This indicates CDOM as the dominant attenuator of both UV and PAR solar radiation and suggests its use as an optical proxy for DOC concentrations in this region. While the Mackenzie input is the main driver of CDOM dynamics in low salinity waters, locally, primary production can create significant increases in CDOM. Extrapolating CDOM to DOC relationships, we estimate that ∼16% of the DOC in the Mackenzie River does not absorb radiation at 350 nm. The discharges of DOC and its chromophoric subset (CDOM) by the Mackenzie River during the MALINA cruise are estimated as ∼0.22 TgC and 0.18 TgC, respectively. Three dissolved fluorescent components (C1-C3) were identified by fluorescence excitation/emission matrix spectroscopy (EEMS) and parallel factor (PARAFAC) analysis. Our results showed an aquatic dissolved organic matter (DOM) component (C1), probably produced in the numerous lakes of the watershed, that co-dominated with a terrestrial humic-like component (C2) in the Mackenzie Delta Sector. This aquatic DOM could partially explain the high CDOM spectral slopes observed in the Beaufort Sea.

  11. Organic Carbon Delivery from a High-Arctic North American Watershed: Implications for Beaufort Sea Carbon Cycling in a Changing Climate

    Science.gov (United States)

    Schreiner, K. M.; Bruner, V. J.; Kessler, J. D.

    2016-12-01

    Riverine delivery of terrestrial organic carbon (OC) and subsequent burial in coastal margins is a significant sink for OC on Earth. The amount of fresh OC compared to old OC buried in coastal margins affects the long-term ratio of O2 to CO2 in the atmosphere. And yet, the fate of OC on marine shelves is not well known. Analysis of the fate of terrestrial OC from Arctic rivers are especially important, as half of the global soil carbon pool resides in the top few meters of Arctic permafrost soils, and much of this OC, more than twice the amount of carbon currently residing in the atmospheric CO2 pool, is thousands of years old and under threat of disturbance from a warming Arctic climate. Flux of this old, deeply-buried permafrost OC to coastal sediments has already been noted in both the Russian and Alaskan Arctic. This study focuses on OC delivered by the Colville River, a medium-sized North American Arctic river that drains the North Slope of Alaska, and has been previously shown to be an important source of extremely old OC to coastal Beaufort Sea sediments. Here we report stable carbon isotopes and radiocarbon ages of particulate OC (POC), dissolved OC (DOC), and surface sediments from the Beaufort Sea near the Colville River outflow and nearby Simpson Lagoon from samples collected in August 2015. In general, DOC ages are younger than POC ages, and both have stable isotope signatures indicative of terrestrial C3 sources. Waters with higher concentrations of DOC tend to have younger radiocarbon ages and more enriched stable isotope signatures, indicating the presence of aquatic primary production. These data represent some of the first water column radiocarbon signatures to be reported from an Arctic river the size of the Colville; while the six largest Arctic rivers have been well studied over the past few decades, much less data is available for small and medium sized Arctic rivers.

  12. Shale Gas characteristics of Permian black shales (Ecca group, Eastern Cape, South Africa)

    Science.gov (United States)

    Geel, Claire; Booth, Peter; Schulz, Hans-Martin; Horsfield, Brian; de Wit, Maarten

    2013-04-01

    This study involves a comprehensive and detailed lithological, sedimentalogical, structural and geochemical description of the lower Ecca Group in the Eastern Cape, South Africa. The Ecca group hosts a ~ 245 million year old organic-rich black shale, which has recently been the focus of interest of petroleum companies worldwide. The shale was deposited under anoxic conditions in a setting which formed as a consequence of retro-arc foreland basin development related to the Cape Fold Belt. This sedimentary/tectonic environment provided the conditions for deeply buried black shales to reach maturity levels for development in the gas window. The investigation site is called the Greystone Area and is situated north of Wolwefontein en route to Jansenville. The area has outcrops of the Dwyka, the Ecca and the lower Beaufort Groups. The outcrops were mapped extensively and the data was used in conjunction with GIS software to produce a detailed geological map. North-south cross sections were drawn to give indication of bed thicknesses and formation depths. Using the field work, data two boreholes were accurately sited on the northern limb of a shallow easterly plunging syncline. The first borehole reached 100m and the second was drilled to 292m depth (100m percussion and 192m core). The second borehole was drilled 200m south of the first, to penetrate the formations at a greater depth and to avoid surface weathering. Fresh core from the upper Dwyka Group, the Prince Albert Formation, the Whitehill Formation, Collingham Formation and part of the Ripon Formation were successfully extracted and a detailed stratigraphic log has been drawn up. The core was sampled during extraction and the samples were immediately sent to the GFZ in Potsdam, Germany, for geochemical analyses. As suspected the black shales of the the Whitehill Formation are high in organic carbon and have an average TOC value of 4.5%, whereas the Prince Albert and Collingham Formation are below 1%. Tmax values

  13. Surface plasmon resonance analysis shows an IgG-isotype-specific defect in ABO blood group antibody formation in patients with common variable immunodeficiency

    Directory of Open Access Journals (Sweden)

    Michael Bernhard Fischer

    2015-05-01

    Full Text Available Background: Common variable immunodeficiency (CVID is the most common clinically severe primary immunodeficiency and comprises a heterogeneous group of patients with recurrent severe bacterial infections due to the failure to produce IgG antibodies after exposure to infectious agents and immunization. Diagnostic recommendations for antibody failure include assessment of isoagglutinins. We have readdressed this four decades old but still accepted recommendation with up to date methodology.Methods: Anti-A/B IgM- and IgG-antibodies were measured by Diamed-ID Micro Typing, surface plasmon resonance (SPR using the Biacore® device and flow cytometry.Results: When Diamed-ID Micro Typing was used, CVID patients (n=34 showed IgG- and IgM-isoagglutinins that were comparable to healthy volunteers (n=28, while all XLA patients (n=8 had none. Anti-A/B IgM-antibodies were present in more than 2/3 of the CVID patients and showed binding kinetics comparable to anti-A/B IgM-antibodies from healthy individuals. A correlation could be found in CVID patients between levels of anti-A/B IgM-antibodies and levels of serum IgM and PnP-IgM-antibodies. In contrast in CVID patients as a group ABO antibodies were significantly decreased when assessed by SPR, which correlated with levels of switched memory, non-switched memory and naïve B cells, but all CVID patients had low/undetectable anti-A/B IgG-antibodies.Conclusion: These results indicate that conventional isoagglutinin assessment and assessment of anti-A/B IgM antibodies are not suited for the diagnosis of impaired antibody production in CVID. Examination of anti-A/B IgG antibodies by SPR provides a useful method for the diagnosis of IgG antibody failure in all CVID patients studied, thus indicating an important additional rationale to start immunoglobulin replacement therapy early in these patients, before post-infectious sequelae develop.

  14. High-Mobility Group Box 1 Mediates Fibroblast Activity via RAGE-MAPK and NF-κB Signaling in Keloid Scar Formation

    Directory of Open Access Journals (Sweden)

    Jihee Kim

    2017-12-01

    Full Text Available Emerging studies have revealed the involvement of high-mobility group box 1 (HMGB1 in systemic fibrotic diseases, yet its role in the cutaneous scarring process has not yet been investigated. We hypothesized that HMGB1 may promote fibroblast activity to cause abnormal cutaneous scarring. In vitro wound healing assay with normal and keloid fibroblasts demonstrated that HMGB1 administration promoted the migration of both fibroblasts with increased speed and a greater traveling distance. Treatment of the HMGB1 inhibitor glycyrrhizic acid (GA showed an opposing effect on both activities. To analyze the downstream mechanism, the protein levels of extracellular signal-regulated kinase (ERK 1/2, protein kinase B (AKT, and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB were measured by western blot analysis. HMGB1 increased the expression levels of ERK1/2, AKT, and NF-κB compared to the control, which was suppressed by GA. HMGB1 promoted both normal and keloid fibroblasts migration to a degree equivalent to that achieved with TGF-β. We concluded that HMGB1 activates fibroblasts via the receptor for advanced glycation end product (RAGE—mitogen-activated protein kinases (MAPK and NF-κB interaction signaling pathways. Further knowledge of the relationship of HMGB1 with skin fibrosis may lead to a promising clinical approach to manage abnormal scarring.

  15. High-Mobility Group Box 1 Mediates Fibroblast Activity via RAGE-MAPK and NF-κB Signaling in Keloid Scar Formation.

    Science.gov (United States)

    Kim, Jihee; Park, Jong-Chul; Lee, Mi Hee; Yang, Chae Eun; Lee, Ju Hee; Lee, Won Jai

    2017-12-28

    Emerging studies have revealed the involvement of high-mobility group box 1 (HMGB1) in systemic fibrotic diseases, yet its role in the cutaneous scarring process has not yet been investigated. We hypothesized that HMGB1 may promote fibroblast activity to cause abnormal cutaneous scarring. In vitro wound healing assay with normal and keloid fibroblasts demonstrated that HMGB1 administration promoted the migration of both fibroblasts with increased speed and a greater traveling distance. Treatment of the HMGB1 inhibitor glycyrrhizic acid (GA) showed an opposing effect on both activities. To analyze the downstream mechanism, the protein levels of extracellular signal-regulated kinase (ERK) 1/2, protein kinase B (AKT), and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) were measured by western blot analysis. HMGB1 increased the expression levels of ERK1/2, AKT, and NF-κB compared to the control, which was suppressed by GA. HMGB1 promoted both normal and keloid fibroblasts migration to a degree equivalent to that achieved with TGF-β. We concluded that HMGB1 activates fibroblasts via the receptor for advanced glycation end product (RAGE)-mitogen-activated protein kinases (MAPK) and NF-κB interaction signaling pathways. Further knowledge of the relationship of HMGB1 with skin fibrosis may lead to a promising clinical approach to manage abnormal scarring.

  16. Facilitating organisational development using a group-based formative assessment and benchmarking method: design and implementation of the International Family Practice Maturity Matrix.

    Science.gov (United States)

    Elwyn, Glyn; Bekkers, Marie-Jet; Tapp, Laura; Edwards, Adrian; Newcombe, Robert; Eriksson, Tina; Braspenning, Jozé; Kuch, Christine; Adzic, Zlata Ozvacic; Ayankogbe, Olayinka; Cvetko, Tatjana; In 't Veld, Kees; Karotsis, Antonis; Kersnik, Janko; Lefebvre, Luc; Mecini, Ilir; Petricek, Goranka; Pisco, Luis; Thesen, Janecke; Turón, José María; van Rossen, Edward; Grol, Richard

    2010-12-01

    Well-organised practices deliver higher-quality care. Yet there has been very little effort so far to help primary care organisations achieve higher levels of team performance and to help them identify and prioritise areas where quality improvement efforts should be concentrated. No attempt at all has been made to achieve a method which would be capable of providing comparisons--and the stimulus for further improvement--at an international level. The development of the International Family Practice Maturity Matrix took place in three phases: (1) selection and refinement of organisational dimensions; (2) development of incremental scales based on a recognised theoretical framework; and (3) testing the feasibility of the approach on an international basis, including generation of an automated web-based benchmarking system. This work has demonstrated the feasibility of developing an organisational assessment tool for primary care organisations that is sufficiently generic to cross international borders and is applicable across a diverse range of health settings, from state-organised systems to insurer-based health economies. It proved possible to introduce this assessment method in 11 countries in Europe and one in Africa, and to generate comparison benchmarks based on the data collected. The evaluation of the assessment process was uniformly positive with the view that the approach efficiently enables the identification of priorities for organisational development and quality improvement at the same time as motivating change by virtue of the group dynamics. We are not aware of any other organisational assessment method for primary care which has been 'born international,' and that has involved attention to theory, dimension selection and item refinement. The principal aims were to achieve an organisational assessment which gains added value by using interaction, engagement comparative benchmarks: aims which have been achieved. The next step is to achieve wider

  17. Paleoproterozoic source contributions to the Sao Roque Group sedimentation: LA-MC-ICPMS U-Pb dating and Sm-Nd systematics of clasts from metaconglomerates of the Boturuna Formation

    Energy Technology Data Exchange (ETDEWEB)

    Henrique-Pinto, Renato; Janasi, Valdecir de Assis; Tassinari, Colombo Celso Gaeta [Universidade de Sao Paulo (USP), SP (Brazil). Inst. de Geociencias. Dept. de Mineralogia e Geotectonica; Simonetti, Antonio [University of Notre Dame, South Bend (United States). Dept. of Civil Engineering and Geological Sciences; Heaman, Larry Michael, E-mail: renatohp@usp.br, E-mail: vajanasi@usp.br, E-mail: ccgtassi@usp.br, E-mail: antonio.simonetti.3@nd.edu, E-mail: larry.heaman@ualberta.ca [University of Alberta, Edmonton (Canada). Dept. of Earth and Atmospheric Sciences

    2012-12-15

    The Sao Roque Group is characterized by volcano-sedimentary sequences, in which deposition probably started in the late Paleoproterozoic. U-Pb dating by LA-MC-ICPMS of zircons extracted from predominantly equigranular monzogranites clasts from Morro Doce and Morro do Polvilho regions, yield paleoproterozoic ages of 2199 {+-}8.5 Ma and 2247 {+-}13 Ma, respectively. These represent the ages for the main source of granite for the metaconglomerates from the Boturuna Formation (basal unit of Sao Roque Group). Its polycyclic history is reinforced by the presence of inherited Archean zircons (2694 {+-}29 Ma) found within the clasts. Moreover, these clasts have also been affected by the Neoproterozoic overprinting event as indicated by their lower intercept Concordia ages. Sm-Nd isotope data for the main clast varieties from the Morro Doce metaconglomerates yield T{sub DM} ages of 2.6 to 2.7 Ga, demonstrating that these granites are the recycling products of an Archean crustal component. The metaconglomerate arkosean framework yields slightly lower {epsilon}{sub Nd(t)} values than those for the clasts, indicating that a younger and/or more primitive source also contributed to the Boturuna Formation. (author)

  18. U-Pb, Pb-Pb, and K-Ar isotopic study and petrography of uraniferous phosphate-bearing rocks in the Thelon Formation, Dubawnt Group, Northwest Territories, Canada

    International Nuclear Information System (INIS)

    Miller, A.R.; Cumming, G.L.; Krstic, D.

    1989-01-01

    The Thelon Formation, uppermost unit of the Dubawnt Group, overlies a regionally extensive paleoweathered zone developed on a wide range of lithochronological units including formations in the lower Dubawnt Group. Authigenic uraniferous phosphate minerals, fluorapatite and goyazite, cementing Thelon conglomerate - sandstone and filling fractures in the underlying paleoweathered zone, were dated in an attempt to better constrain the age of Thelon sedimentation and diagenesis. The oldest age, 1720 ± 6 Ma, derived from phosphate-cemented sediments, is interpreted as a minimum age for diagenesis and therefore brackets initial Thelon sedimentation between emplacement of fluorite-bearing granites at 1753 Ma and authigenic phosphate cementation at 1720 Ma. Additional ages of 1685 ± 4 and 1647 Ma are interpreted as remobilization or subsequent cementation events. K-Ar ages on illite, 1386 ± 37 and 1266 ± 31 Ma, from the paleoweathered zone and basal conglomerate, respectively, are significantly younger than ages derived from coexisting phosphate. These K-Ar ages recorded hydrothermal events that may be related to processes associated with unconformity-type uranium mineralization at approximately 1400-1300 Ma. Ages from the Thelon Basin permit geochronologic correlations with the Athabasca and Hornby basins, long correlated on the basis of similarities in sedimentation, stratigraphy, and tectonic setting

  19. Quantifying the Bering Strait Oceanic Fluxes and their Impacts on Sea-Ice and Water Properties in the Chukchi and Beaufort Seas and Western Arctic Ocean for 2013-2014

    Science.gov (United States)

    2016-07-27

    impacts on sea-ice and water properties in the Chukchi and Beaufort Seas and western Arctic Ocean for 2013-2014 Rebecca Woodgate Polar Science...and G. R. Bigg (2002), Impact of flow through the Canadian Archipelago and Bering Strait on the North Atlantic and Arctic circulation: an ocean ...Technical 3. DATES COVERED (From - To) Feb 2013 - April 2016 4. TITLE AND SUBTITLE Quantifying the Bering Strait oceanic fluxes and their impacts

  20. Overview of the NEA/OECD Seabed Working Group. An international programme for assessment of the feasibility of disposal of high-level waste in geological formations beneath the ocean

    International Nuclear Information System (INIS)

    Anderson, D.R.; Boyer, D.G.; Rueegger, B.; Olivier, J.P.

    1984-01-01

    The NEA/OECD Seabed Working Group, a subcommittee of the Radioactive Waste Management Committee (whose present membership includes Canada, the CEC, the Federal Republic of Germany, France, Japan, the Netherlands, the United Kingdom and the USA), is addressing the questions of how best to utilize the resources of the ocean. Since the beginning of time, the oceans have been the 'garbage dumps' of the land masses. Erosional processes continuously tear down mountains and the land and move them into the oceans. Most of the elements in nuclear waste are chemically identical to those being eroded, cycled and deposited in the ocean. Could the ocean's geological formations be used for the disposal of these radioactive wastes. The Seabed Working Group is divided into eight task groups: System Analysis, Site Selection, Sediment and Rock, Engineering Studies, Biology, Physical Oceanography, Waste Form and Canister, and Institutional. Within each of the groups a set of predictive models is being developed, the appropriate properties acquired, and predictions made. Laboratory and in-situ field tests will be conducted to verify the accuracy of the model predictions. The model sections will then be combined into a systems model to yield an estimate of the feasibility, risk and cost of this waste disposal option. The results to date of the technical and environmental feasibility studies of seabed disposal appear to be leading to a conclusion that this is technically feasible. Institutional feasibility is just beginning to be considered. (author)

  1. Comparative analysis of the calcretization process in the Marilia formations (Bauru group - Brasil) and Mercedes ( Paysandu group - Uruguay), Upper Cretaceous of the Parana basin; Analisis comparativo de los procesos de calcretizacion en las Formaciones Marilia (Grupo Bauru-Brasil) y Mercedes (Grupo Paysandu-Uruguay), Cretacico Superior de la cuenca de Parana

    Energy Technology Data Exchange (ETDEWEB)

    Veroslavsky, G; Etchebehere, M; Sad, A; Fulfaro, J

    1998-07-01

    Pedogenic and non-pedogenic calcrete facies are very common feature of Marilia (Brazil) and Mercedes (Uruguay) formations in the Parana Basin. The non-pedogenic ones constitute massive limestone facies that have been recently interpreted as groundwater calcretes. These limestones are exploited in both countries to supply raw materials to Portland cement and soil conditioner in origin and age of calcretization phenomena. In Uruguay, the calcretization process seens to be band formation. Field relationships and fossil assemblage point to a Paleocene (or later) age for the calcretization. In Brazilian territory, the groundwater calcretes aresupposed to be of Upper Cretaceous age due to the presence of dinosaurs scattered through the Bauru Group, including siliciclastic beds below and above the calcretes. The authors assume that calcretization processes are similar in both countries (host rocks, intensity, size, textures, geometries and economic potential). The main difference is in age of the calcretization. (author)

  2. On Peer Networks and Group Formation

    OpenAIRE

    Ballester Pla, Coralio

    2005-01-01

    Consultable des del TDX Títol obtingut de la portada digitalitzada En el artículo «NP-completeness in Hedonic Games», identificamos algunas limitaciones significativas de los modelos estándar de juegos cooperativos: A menudo, es imposible alcanzar una organización estable de una sociedad en una cantidad de tiempo razonable. Las implicaciones básicas de estos resultados son las siguientes, Primero, desde un punto de vista positivo, las sociedades están «condenadas» a evolucionar constant...

  3. The Pan-STARRS1 medium-deep survey: The role of galaxy group environment in the star formation rate versus stellar mass relation and quiescent fraction out to z ∼ 0.8

    International Nuclear Information System (INIS)

    Lin, Lihwai; Chen, Chin-Wei; Coupon, Jean; Hsieh, Bau-Ching; Jian, Hung-Yu; Foucaud, Sebastien; Norberg, Peder; Bower, R. G.; Cole, Shaun; Arnalte-Mur, Pablo; Draper, P.; Heinis, Sebastien; Phleps, Stefanie; Chen, Wen-Ping; Lee, Chien-Hsiu; Burgett, William; Chambers, K. C.; Denneau, L.; Flewelling, H.; Hodapp, K. W.

    2014-01-01

    Using a large optically selected sample of field and group galaxies drawn from the Pan-STARRS1 Medium-Deep Survey (PS1/MDS), we present a detailed analysis of the specific star formation rate (SSFR)—stellar mass (M * ) relation, as well as the quiescent fraction versus M * relation in different environments. While both the SSFR and the quiescent fraction depend strongly on stellar mass, the environment also plays an important role. Using this large galaxy sample, we confirm that the fraction of quiescent galaxies is strongly dependent on environment at a fixed stellar mass, but that the amplitude and the slope of the star-forming sequence is similar between the field and groups: in other words, the SSFR-density relation at a fixed stellar mass is primarily driven by the change in the star-forming and quiescent fractions between different environments rather than a global suppression in the star formation rate for the star-forming population. However, when we restrict our sample to the cluster-scale environments (M > 10 14 M ☉ ), we find a global reduction in the SSFR of the star-forming sequence of 17% at 4σ confidence as opposed to its field counterpart. After removing the stellar mass dependence of the quiescent fraction seen in field galaxies, the excess in the quiescent fraction due to the environment quenching in groups and clusters is found to increase with stellar mass, although deeper and larger data from the full PS1/MDS will be required to draw firm conclusions. We argue that these results are in favor of galaxy mergers to be the primary environment quenching mechanism operating in galaxy groups whereas strangulation is able to reproduce the observed trend in the environment quenching efficiency and stellar mass relation seen in clusters. Our results also suggest that the relative importance between mass quenching and environment quenching depends on stellar mass—the mass quenching plays a dominant role in producing quiescent galaxies for more

  4. The Pan-STARRS1 medium-deep survey: The role of galaxy group environment in the star formation rate versus stellar mass relation and quiescent fraction out to z ∼ 0.8

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Lihwai; Chen, Chin-Wei; Coupon, Jean; Hsieh, Bau-Ching [Institute of Astronomy and Astrophysics, Academia Sinica, Taipei 106, Taiwan, R.O.C. (China); Jian, Hung-Yu [Department of Physics, National Taiwan University, Taipei 106, Taiwan, R.O.C. (China); Foucaud, Sebastien [Department of Earth Sciences, National Taiwan Normal University, N°88, Tingzhou Road, Sec. 4, Taipei 11677, Taiwan, R.O.C. (China); Norberg, Peder; Bower, R. G.; Cole, Shaun; Arnalte-Mur, Pablo; Draper, P. [Institute for Computational Cosmology, Department of Physics, Durham University, South Road, Durham DH1 3LE (United Kingdom); Heinis, Sebastien [Department of Astronomy, University of Maryland, MD 20742 (United States); Phleps, Stefanie [Max-Planck-Institut für Extraterrestrische Physik, Giessenbachstraße, D-85748 Garching (Germany); Chen, Wen-Ping [Graduate Institute of Astronomy, National Central University, Chung-Li 32054, Taiwan, R.O.C. (China); Lee, Chien-Hsiu [University Observatory Munich, Scheinerstrasse 1, D-81679 Munich (Germany); Burgett, William; Chambers, K. C.; Denneau, L.; Flewelling, H.; Hodapp, K. W., E-mail: lihwailin@asiaa.sinica.edu.tw [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); and others

    2014-02-10

    Using a large optically selected sample of field and group galaxies drawn from the Pan-STARRS1 Medium-Deep Survey (PS1/MDS), we present a detailed analysis of the specific star formation rate (SSFR)—stellar mass (M {sub *}) relation, as well as the quiescent fraction versus M {sub *} relation in different environments. While both the SSFR and the quiescent fraction depend strongly on stellar mass, the environment also plays an important role. Using this large galaxy sample, we confirm that the fraction of quiescent galaxies is strongly dependent on environment at a fixed stellar mass, but that the amplitude and the slope of the star-forming sequence is similar between the field and groups: in other words, the SSFR-density relation at a fixed stellar mass is primarily driven by the change in the star-forming and quiescent fractions between different environments rather than a global suppression in the star formation rate for the star-forming population. However, when we restrict our sample to the cluster-scale environments (M > 10{sup 14} M {sub ☉}), we find a global reduction in the SSFR of the star-forming sequence of 17% at 4σ confidence as opposed to its field counterpart. After removing the stellar mass dependence of the quiescent fraction seen in field galaxies, the excess in the quiescent fraction due to the environment quenching in groups and clusters is found to increase with stellar mass, although deeper and larger data from the full PS1/MDS will be required to draw firm conclusions. We argue that these results are in favor of galaxy mergers to be the primary environment quenching mechanism operating in galaxy groups whereas strangulation is able to reproduce the observed trend in the environment quenching efficiency and stellar mass relation seen in clusters. Our results also suggest that the relative importance between mass quenching and environment quenching depends on stellar mass—the mass quenching plays a dominant role in producing quiescent

  5. The Jurassic of Denmark and Greenland: Palynostratigraphy and palaeoenvironments of the Rævekløft, Gule Horn and Ostreaelv Formations (Lower–Middle Jurassic, Neill Klinter Group, Jameson Land, East Greenland

    Directory of Open Access Journals (Sweden)

    Koppelhus, Eva B.

    2003-10-01

    Full Text Available The Neill Klinter Group of Jameson Land, East Greenland contains rich and diverse palynomorph assemblages. Spores, pollen and freshwater algae dominate most of the samples, but dinoflagellatecysts and acritarchs also form important components. The ages suggested by the palynomorphs from the Rævekløft, Gule Horn and Ostreaelv Formations span the period from the Early Pliensbachian to the early Aalenian. The number of palynomorphs identified totals 136,including 83 miospore and 53 microplankton species; they are grouped into seven palynological assemblage zones.In general, there is good agreement between the palynological and sedimentological data, and the palynological data has refined the understanding of the depositional palaeoenvironments ofthe Neill Klinter Group. In some cases, the boundaries of the palynological assemblage zones are congruent with major sequence stratigraphic surfaces and the palynological data thus supportthe sequence stratigraphic interpretation. In other cases, however, regional correlation indicates that the zone boundaries cross important sequence stratigraphic surfaces, such as sequenceboundaries; such behaviour is thought to reflect the facies-dependent nature of certain of the palynological assemblage zones. The pattern of palynological events in East Greenland has alsobeen recognised on the mid-Norwegian shelf.

  6. Long-term changes of mercury levels in ringed seal (Phoca hispida) from Amundsen Gulf, and beluga (Delphinapterus leucas) from the Beaufort Sea, western Canadian Arctic

    Energy Technology Data Exchange (ETDEWEB)

    Outridge, P.M., E-mail: outridge@nrcan.gc.ca [Geological Survey of Canada, Natural Resources Canada, 601 Booth Street, Ottawa, Canada K1A 0E8 (Canada); Hobson, K.A. [Environment Canada, 11 Innovation Boulevard, Saskatoon, Canada S7N 3H5 (Canada); Savelle, J. [Department of Anthropology, McGill University, 855 Sherbrooke Street, Montreal, Canada H3A 2T7 (Canada)

    2009-11-15

    Mercury (Hg) concentrations were determined in the canine teeth of ringed seals (Phoca hispida) harvested during the 13th-14th, late 19th and early 21st Centuries in Amundsen Gulf, Northwest Territories, Canada. Most historical and pre-industrial teeth contained undetectable Hg levels (i.e. < 1.0 ng/g DW), whereas samples from 2001-03 contained up to 12 ng/g DW in an age-dependent pattern. Assuming a median [Hg] value in 13th-14th Century teeth of half the detection limit (i.e. 0.5 ng/g DW), geometric means of Hg in modern teeth were 9-17 times those of seals in the 14th Century, equivalent to an anthropogenic input of 89-94% of total Hg in modern seals. These results corroborate a previous study of beluga (Delphinapterus leucas) in the nearby Beaufort Sea. While the seals' trophic position (inferred from {delta}{sup 15}N values) did not change over time, modern {delta}{sup 13}C values were lower by about 2 per mille than in the 14th and 19th Centuries. This could be due to increased dissolution of anthropogenically derived CO{sub 2} in the ocean from the atmosphere, but could also indicate more offshore pelagic feeding by modern seals, which might be a factor in their Hg exposure. New tooth [Hg] data are also presented for the Beaufort Sea beluga, using recently-discovered museum samples collected in 1960/61, which showed that most of the anthropogenic contribution to beluga Hg had already taken effect by 1960 (reaching {approx} 75% of total Hg). Taken together, the long-term seal and beluga data indicate that whereas Hg levels in the marine ecosystems of the western Canadian Arctic were probably unchanged from pre-industrial times up to the late 19th Century, there was a significant, many-fold increase in the early to mid-20th Century, but little or no change after about the early 1960s.

  7. Dramatic variability of the carbonate system at a temperate coastal ocean site (Beaufort, North Carolina, USA is regulated by physical and biogeochemical processes on multiple timescales.

    Directory of Open Access Journals (Sweden)

    Zackary I Johnson

    Full Text Available Increasing atmospheric carbon dioxide (CO2 from anthropogenic sources is acidifying marine environments resulting in potentially dramatic consequences for the physical, chemical and biological functioning of these ecosystems. If current trends continue, mean ocean pH is expected to decrease by ~0.2 units over the next ~50 years. Yet, there is also substantial temporal variability in pH and other carbon system parameters in the ocean resulting in regions that already experience change that exceeds long-term projected trends in pH. This points to short-term dynamics as an important layer of complexity on top of long-term trends. Thus, in order to predict future climate change impacts, there is a critical need to characterize the natural range and dynamics of the marine carbonate system and the mechanisms responsible for observed variability. Here, we present pH and dissolved inorganic carbon (DIC at time intervals spanning 1 hour to >1 year from a dynamic, coastal, temperate marine system (Beaufort Inlet, Beaufort NC USA to characterize the carbonate system at multiple time scales. Daily and seasonal variation of the carbonate system is largely driven by temperature, alkalinity and the balance between primary production and respiration, but high frequency change (hours to days is further influenced by water mass movement (e.g. tides and stochastic events (e.g. storms. Both annual (~0.3 units and diurnal (~0.1 units variability in coastal ocean acidity are similar in magnitude to 50 year projections of ocean acidity associated with increasing atmospheric CO2. The environmental variables driving these changes highlight the importance of characterizing the complete carbonate system rather than just pH. Short-term dynamics of ocean carbon parameters may already exert significant pressure on some coastal marine ecosystems with implications for ecology, biogeochemistry and evolution and this shorter term variability layers additive effects and

  8. Sulfate reduction and methane oxidation activity below the sulfate-methane transition zone in Alaskan Beaufort Sea continental margin sediments: Implications for deep sulfur cycling

    Science.gov (United States)

    Treude, Tina; Krause, Stefan; Maltby, Johanna; Dale, Andrew W.; Coffin, Richard; Hamdan, Leila J.

    2014-11-01

    Two ∼6 m long sediment cores were collected along the ∼300 m isobath on the Alaskan Beaufort Sea continental margin. Both cores showed distinct sulfate-methane transition zones (SMTZ) at 105 and 120 cm below seafloor (cmbsf). Sulfate was not completely depleted below the SMTZ but remained between 30 and 500 μM. Sulfate reduction and anaerobic oxidation of methane (AOM) determined by radiotracer incubations were active throughout the methanogenic zone. Although a mass balance could not explain the source of sulfate below the SMTZ, geochemical profiles and correlation network analyses of biotic and abiotic data suggest a cryptic sulfur cycle involving iron, manganese and barite. Inhibition experiments with molybdate and 2-bromoethanesulfonate (BES) indicated decoupling of sulfate reduction and AOM and competition between sulfate reducers and methanogens for substrates. While correlation network analyses predicted coupling of AOM to iron reduction, the addition of manganese or iron did not stimulate AOM. Since none of the classical archaeal anaerobic methanotrophs (ANME) were abundant, the involvement of unknown or unconventional phylotypes in AOM is conceivable. The resistance of AOM activity to inhibitors implies deviation from conventional enzymatic pathways. This work suggests that the classical redox cascade of electron acceptor utilization based on Gibbs energy yields does not always hold in diffusion-dominated systems, and instead biotic processes may be more strongly coupled to mineralogy.

  9. Long-term changes of mercury levels in ringed seal (Phoca hispida) from Amundsen Gulf, and beluga (Delphinapterus leucas) from the Beaufort Sea, western Canadian Arctic

    International Nuclear Information System (INIS)

    Outridge, P.M.; Hobson, K.A.; Savelle, J.

    2009-01-01

    Mercury (Hg) concentrations were determined in the canine teeth of ringed seals (Phoca hispida) harvested during the 13th-14th, late 19th and early 21st Centuries in Amundsen Gulf, Northwest Territories, Canada. Most historical and pre-industrial teeth contained undetectable Hg levels (i.e. 15 N values) did not change over time, modern δ 13 C values were lower by about 2 per mille than in the 14th and 19th Centuries. This could be due to increased dissolution of anthropogenically derived CO 2 in the ocean from the atmosphere, but could also indicate more offshore pelagic feeding by modern seals, which might be a factor in their Hg exposure. New tooth [Hg] data are also presented for the Beaufort Sea beluga, using recently-discovered museum samples collected in 1960/61, which showed that most of the anthropogenic contribution to beluga Hg had already taken effect by 1960 (reaching ∼ 75% of total Hg). Taken together, the long-term seal and beluga data indicate that whereas Hg levels in the marine ecosystems of the western Canadian Arctic were probably unchanged from pre-industrial times up to the late 19th Century, there was a significant, many-fold increase in the early to mid-20th Century, but little or no change after about the early 1960s.

  10. Stellar formation

    CERN Document Server

    Reddish, V C

    1978-01-01

    Stellar Formation brings together knowledge about the formation of stars. In seeking to determine the conditions necessary for star formation, this book examines questions such as how, where, and why stars form, and at what rate and with what properties. This text also considers whether the formation of a star is an accident or an integral part of the physical properties of matter. This book consists of 13 chapters divided into two sections and begins with an overview of theories that explain star formation as well as the state of knowledge of star formation in comparison to stellar structure

  11. A SPECTROSCOPICALLY CONFIRMED EXCESS OF 24 μm SOURCES IN A SUPER GALAXY GROUP AT z = 0.37: ENHANCED DUSTY STAR FORMATION RELATIVE TO THE CLUSTER AND FIELD ENVIRONMENT

    International Nuclear Information System (INIS)

    Tran, Kim-Vy H.; Saintonge, Amelie; Moustakas, John; Bai, Lei; Zaritsky, Dennis; Gonzalez, Anthony H.; Kautsch, Stefan J.; Holden, Bradford P.

    2009-01-01

    To trace how dust-obscured star formation varies with environment, we compare the fraction of 24 μm sources in a super galaxy group to the field and a rich galaxy cluster at z ∼ 0.35. We draw on multi-wavelength observations 9 Based on observations made with (1) The ESO telescopes at Paranal Observatories under program IDs 072.A-0367, 076.B-0362, 078.B-0409; (2) the NASA/ESA Hubble Space Telescope (GO-10499); STScI is operated by the association of Universities for Research in Astronomy, Inc. under the NASA contract NAS 5-26555; (3) the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology under a contract with NASA; support for this work was provided by NASA through an award issued by JPL/Caltech (GO-20683); (4) the Chandra X-ray Observatory Center, which is operated by the Smithsonian Astrophysical Observatory for and on behalf of the National Aeronautics Space Administration under contract NAS8-03060; and (5) the Magellan 6.5 m telescope operated by OCIW. that combine Hubble, Chandra, and Spitzer imaging with extensive optical spectroscopy (>1800 redshifts) to isolate galaxies in each environment and thus ensure a uniform analysis. We focus on the four galaxy groups (σ 1D = 303-580 km s -1 ) in supergroup 1120-12 that will merge to form a galaxy cluster comparable in mass to Coma. We find that (1) the fraction of supergroup galaxies with SFR IR ≥ 3 M sun yr -1 is 4 times higher than in the cluster (32% ± 5% versus 7% ± 2%); (2) the supergroup's infrared luminosity function confirms that it has a higher density of IR members compared to the cluster and includes bright IR sources (log(L IR )[erg s -1 ] >45) not found in galaxy clusters at z ∼ * )[M sun ] IR ≥ 3 M sun yr -1 members that are outside the group cores (R proj ≥ 0.5 Mpc); once their star formation is quenched, most will evolve into faint red galaxies. Our analysis indicates that the supergroup's 24 μm population also differs from

  12. Relationships between depth and δ15N of Arctic benthos vary among regions and trophic functional groups

    Science.gov (United States)

    Stasko, Ashley D.; Bluhm, Bodil A.; Reist, James D.; Swanson, Heidi; Power, Michael

    2018-05-01

    Stable isotope ratios of nitrogen (δ15N) of benthic primary consumers are often significantly related to water depth. This relationship is commonly attributed to preferential uptake of 14N from sinking particulate organic matter (POM) by microbes, and suggests that relationships between δ15N and water depth may be affected by local POM sources and flux dynamics. We examined the relationships between δ15N and water depth (20-500 m) for six trophic functional groups using a mixed effects modelling approach, and compared relationships between two contiguous Arctic marine ecosystems with different POM sources and sinking export dynamics: the Canadian Beaufort Sea and Amundsen Gulf. We demonstrate for the first time in the Arctic that δ15N values of mobile epifaunal carnivores increased as a function of depth when considered separately from benthopelagic and infaunal carnivores, which contrarily did not exhibit increasing δ15N with depth. The δ15N of suspension/filter feeders, infaunal deposit feeders and bulk sediment also increased with water depth, and the slopes of the relationships were steeper in the Amundsen Gulf than in the Beaufort Sea. We propose that regional differences in slopes reflect differences in POM sources exported to the benthos. In the Beaufort Sea, terrestrial POM discharged from the Mackenzie River quantitatively dominates the sedimentary organic matter across the continental shelf and slope, dampening change in δ15N of benthic POM with depth. In the Amundsen Gulf, we attribute a faster rate of change in δ15N of POM with increasing depth to larger contributions of marine-derived POM to the benthic sedimentary pool, which had likely undergone extensive biological transformation in the productive offshore pelagic zone. Differences in POM input regimes among regions should be considered when comparing food webs using stable isotopes, as such differences may impact the rate at which consumer δ15N changes with depth.

  13. Study Groups in Denmark

    DEFF Research Database (Denmark)

    Hjorth, Poul G.

    2007-01-01

    Since 1998 European Study Groups have been held in Denmark, and Danish companies from LEGO and NOVO to very small high-tech firms have participated. I briefly describe the history, the organisation and the format of the Danish Study Groups, and highlight a few problem solutions.......Since 1998 European Study Groups have been held in Denmark, and Danish companies from LEGO and NOVO to very small high-tech firms have participated. I briefly describe the history, the organisation and the format of the Danish Study Groups, and highlight a few problem solutions....

  14. Galaxy formation

    International Nuclear Information System (INIS)

    Silk, J.; Di Cintio, A.; Dvorkin, I.

    2014-01-01

    Galaxy formation is at the forefront of observation and theory in cosmology. An improved understanding is essential for improving our knowledge both of the cosmological parameters, of the contents of the universe, and of our origins. In these lectures intended for graduate students, galaxy formation theory is reviewed and confronted with recent observational issues. In lecture 1, the following topics are presented: star formation considerations, including IMF, star formation efficiency and star formation rate, the origin of the galaxy luminosity function, and feedback in dwarf galaxies. In lecture 2, we describe formation of disks and massive spheroids, including the growth of supermassive black holes, negative feedback in spheroids, the AGN-star formation connection, star formation rates at high redshift and the baryon fraction in galaxies.

  15. Chapter 7. The GIS project for the geologic assessment of undiscovered oil and gas in the Cotton Valley group and Travis Peak and Hosston formations, East Texas basin and Louisiana-Mississippi salt basins provinces.

    Science.gov (United States)

    Biewick, Laura

    2006-01-01

    A geographic information system (GIS) focusing on the Upper Jurassic-Lower Cretaceous Cotton Valley Group and the Lower Cretaceous Travis Peak and Hosston Formations in the northern Gulf Coast region was developed as a visual-analysis tool for the U.S. Geological Survey's 2002 assessment of undiscovered, technically recoverable oil and natural gas resources in the East Texas Basin and Louisiana-Mississippi Salt Basins Provinces. The Central Energy Resources Team of the U.S. Geological Survey has also developed an Internet Map Service to deliver the GIS data to the public. This mapping tool utilizes information from a database about the oil and natural gas endowment of the United States-including physical locations of geologic and geographic data-and converts the data into visual layers. Portrayal and analysis of geologic features on an interactive map provide an excellent tool for understanding domestic oil and gas resources for strategic planning, formulating economic and energy policies, evaluating lands under the purview of the Federal Government, and developing sound environmental policies. Assessment results can be viewed and analyzed or downloaded from the internet web site, http://energy.cr.usgs.gov/oilgas/noga/ .

  16. UV/PAR radiations and DOM properties in surface coastal waters of the Canadian shelf of the Beaufort Sea during summer 2009

    Science.gov (United States)

    Para, J.; Charrière, B.; Matsuoka, A.; Miller, W. L.; Rontani, J. F.; Sempéré, R.

    2012-11-01

    Water masses from the Beaufort Sea in the Arctic Ocean were evaluated for dissolved organic carbon (DOC), and optical characteristics including UV and PAR diffuse attenuation (Kd), and chromophoric and fluorescent dissolved organic matter (CDOM and FDOM) as part of the MALINA field campaign (30 July to 27 August). Even with relatively low mean daily solar radiation incident on the sea surface (0.12 ± 0.03, 8.46 ± 1.64 and 18.09 ± 4.20 kJ m-2 for UV-B (305 nm), UV-A (380 nm) and PAR, respectively), we report significant light penetration with 10% irradiance depths (Z10% (λ)) reaching 9.5 m for 340 nm (UV-A) radiation in the Eastern sector and 4.5 m in the Mackenzie River influenced area (Western sector). Spectral absorption coefficients (aCDOM (350 nm) (m-1)) were significantly correlated to both diffuse attenuation coefficients (Kd) in the UV-A and UV-B and to DOC concentrations. This indicates CDOM as the dominant attenuator of UV solar radiation and suggests its use as an optical proxy for DOC concentrations in this region. Extrapolating CDOM to DOC relationships, we estimate that ~ 16% of the DOC in the Mackenzie River does not absorb radiation at 350 nm. DOC and CDOM discharges by the Mackenzie River during the MALINA Cruise are estimated as ~ 0.22 TgC and 0.18 TgC, respectively. Three dissolved fluorescent components (C1-C3) were identified by fluorescence Excitation/Emission Matrix Spectroscopy (EEMS) and PARAFAC analysis. Our results showed an in-situ biological component (C1) that co-dominated with a terrestrial humic-like component (C2) in the Mackenzie Delta sector, whereas the protein-like (C3) component dominated in the saltiest waters of the North East sector.

  17. Long-term patterns of benthic irradiance and kelp production in the central Beaufort sea reveal implications of warming for Arctic inner shelves

    Science.gov (United States)

    Bonsell, Christina; Dunton, Kenneth H.

    2018-03-01

    This study synthesizes a multidecadal dataset of annual growth of the Arctic endemic kelp Laminaria solidungula and corresponding measurements of in situ benthic irradiance from Stefansson Sound in the central Beaufort Sea. We incorporate long-term data on sea ice concentration (National Sea Ice Data Center) and wind (National Weather Service) to assess how ice extent and summer wind dynamics affect the benthic light environment and annual kelp production. We find evidence of significant changes in sea ice extent in Stefansson Sound, with an extension of the ice-free season by approximately 17 days since 1979. Although kelp elongation at 5-7 m depths varies significantly among sites and years (3.8-49.8 cm yr-1), there is no evidence for increased production with either earlier ice break-up or a longer summer ice-free period. This is explained by very low light transmittance to the benthos during the summer season (mean daily percent surface irradiance ± SD: 1.7 ± 3.6 to 4.5 ± 6.6, depending on depth, with light attenuation values ranging from 0.5 to 0.8 m-1), resulting in minimal potential for kelp production on most days. Additionally, on month-long timescales (35 days) in the ice-free summer, benthic light levels are negatively related to wind speed. The frequent, wind-driven resuspension of sediments following ice break-up significantly reduce light to the seabed, effectively nullifying the benefits of an increased ice-free season on annual kelp growth. Instead, benthic light and primary production may depend substantially on the 1-3 week period surrounding ice break-up when intermediate sea ice concentrations reduce wind-driven sediment resuspension. These results suggest that both benthic and water column primary production along the inner shelf of Arctic marginal seas may decrease, not increase, with reductions in sea ice extent.

  18. Estimating absorption coefficients of colored dissolved organic matter (CDOM) using a semi-analytical algorithm for Southern Beaufort Sea (Canadian Arctic) waters: application to deriving concentrations of dissolved organic carbon from space

    Science.gov (United States)

    Matsuoka, A.; Hooker, S. B.; Bricaud, A.; Gentili, B.; Babin, M.

    2012-10-01

    A series of papers have suggested that freshwater discharge, including a large amount of dissolved organic matter (DOM), has increased since the middle of the 20th century. In this study, a semi-analytical algorithm for estimating light absorption coefficients of the colored fraction of DOM (CDOM) was developed for Southern Beaufort Sea waters using remote sensing reflectance at six wavelengths in the visible spectral domain corresponding to MODIS ocean color sensor. This algorithm allows to separate colored detrital matter (CDM) into CDOM and non-algal particles (NAP) by determining NAP absorption using an empirical relationship between NAP absorption and particle backscattering coefficients. Evaluation using independent datasets, that were not used for developing the algorithm, showed that CDOM absorption can be estimated accurately to within an uncertainty of 35% and 50% for oceanic and turbid waters, respectively. In situ measurements showed that dissolved organic carbon (DOC) concentrations were tightly correlated with CDOM absorption (r2 = 0.97). By combining the CDOM absorption algorithm together with the DOC versus CDOM relationship, it is now possible to estimate DOC concentrations in the near-surface layer of the Southern Beaufort Sea using satellite ocean color data. DOC concentrations in the surface waters were estimated using MODIS ocean color data, and the estimates showed reasonable values compared to in situ measurements. We propose a routine and near real-time method for deriving DOC concentrations from space, which may open the way to an estimate of DOC budgets for Arctic coastal waters.

  19. A construção da identidade de sujeitos deficientes no grupo terapêutico-fonoaudiológico Identity formation of disabled individuals within a speech therapy group

    Directory of Open Access Journals (Sweden)

    Gabriela Almeida Leite

    2008-08-01

    the internalization of roles. These roles are defined, in the first instance, by those persons who provide the most concrete reference points for the child, in particular their family, and beyond that by the wider social group to which they belong. Our objective was to reflect upon the formation of the personal identity of mentally disabled young people who were receiving speech therapy, this therapy being conducted in a group context. Transcripts of the language used by the subjects in constructing their self image were analyzed. This study was based upon the results obtained from previous research, conducted with groups of siblings of subjects classified as mentally disabled. These results revealed a negative image held by those siblings of their disabled brother or sister. The material analyzed is part of a data bank of videotapes, of disabled youngsters receiving group speech therapy in a school clinic setting, taken over a two year period. This data was transcribed and analyzed according to the guidelines of micro genetic analysis, taking into consideration minute details of interviews and in particular details and clips of interactive episodes. The examination of the data was directed towards the actions of the subjects of the study, their interpersonal relations and the social context in which these took place. The analysis conducted in this study aims to establish a relationship between the images these subjects have of themselves and the image put across by the social group to which they belong. The results demonstrated the resonance of the discourse of the social group in the verbalizations of the subjects. We conclude that to transform the image that the subjects with intellectual disability have of themselves it is necessary to direct actions to those who are close to them, namely family, friends, colleagues and their social group in general.

  20. Formative (measurement)

    NARCIS (Netherlands)

    Fassott, G.; Henseler, Jörg; Cooper, C.; Lee, N.; Farrell, A.

    2015-01-01

    When using measurement models with multiple indicators, researchers need to decide about the epistemic relationship between the latent variable and its indicators. In this article, we describe the nature, the estimation, the characteristics, and the validity assessment of formative measurement

  1. Do common eiders nest in kin groups? Microgeographic genetic structure in a philopatric sea duck

    Science.gov (United States)

    Sonsthagen, S.A.; Talbot, S.L.; Lanctot, Richard B.; McCracken, K.G.

    2010-01-01

    We investigated local genetic associations among female Pacific common eiders (Somateria mollissima v-nigrum) nesting in a stochastic Arctic environment within two groups of barrier islands (Simpson Lagoon and Mikkelsen Bay) in the Beaufort Sea, Alaska. Nonrandom genetic associations were observed among nesting females using regional spatial autocorrelation analyses for distance classes up to 1000 m in Simpson Lagoon. Nearest-neighbour analyses identified clusters of genetically related females with positive lr values observed for 0-13% and 0-7% of the comparisons in Simpson Lagoon and Mikkelsen Bay, respectively, across years. These results indicate that a proportion of females are nesting in close proximity to more genetically related individuals, albeit at low frequency. Such kin groupings may form through active association between relatives or through natal philopatry and breeding site fidelity. Eiders nest in close association with driftwood, which is redistributed annually by seasonal storms. Yet, genetic associations were still observed. Microgeographic structure may thus be more attributable to kin association than natal philopatry and site fidelity. However, habitat availability may also influence the level of structure observed. Regional structure was present only within Simpson Lagoon and this island group includes at least three islands with sufficient driftwood for colonies, whereas only one island at Mikkelsen Bay has these features. A long-term demographic study is needed to understand more fully the mechanisms that lead to fine-scale genetic structure observed in common eiders breeding in the Beaufort Sea. ?? Published 2010. This article is a US Government work and is in the public domain in the USA.

  2. Assessing the potential impacts of declining Arctic sea ice cover on the photochemical degradation of dissolved organic matter in the Chukchi and Beaufort Seas

    Science.gov (United States)

    Logvinova, Christie L.; Frey, Karen E.; Mann, Paul J.; Stubbins, Aron; Spencer, Robert G. M.

    2015-11-01

    A warming and shifting climate in the Arctic has led to significant declines in sea ice over the last several decades. Although these changes in sea ice cover are well documented, large uncertainties remain in how associated increases in solar radiation transmitted to the underlying ocean water column will impact heating, biological, and biogeochemical processes in the Arctic Ocean. In this study, six under-ice marine, two ice-free marine, and two ice-free terrestrially influenced water samples were irradiated using a solar simulator for 72 h (representing ~10 days of ambient sunlight) to investigate dissolved organic matter (DOM) dynamics from the Chukchi and Beaufort Seas. Solar irradiation caused chromophoric DOM (CDOM) light absorption at 254 nm to decrease by 48 to 63%. An overall loss in total DOM fluorescence intensity was also observed at the end of all experiments, and each of six components identified by parallel factor (PARAFAC) analysis was shown to be photoreactive in at least one experiment. Fluorescent DOM (FDOM) also indicated that the majority of DOM in under-ice and ice-free marine waters was likely algal-derived. Measurable changes in dissolved organic carbon (DOC) were only observed for sites influenced by riverine runoff. Losses of CDOM absorbance at shorter wavelengths suggest that the beneficial UV protection currently received by marine organisms may decline with the increased light transmittance associated with sea ice melt ponding and overall reductions of sea ice. Our FDOM analyses demonstrate that DOM irrespective of source was susceptible to photobleaching. Additionally, our findings suggest that photodegradation of CDOM in under-ice waters is not currently a significant source of carbon dioxide (CO2) (i.e., we did not observe systematic DOC loss). However, increases in primary production and terrestrial freshwater export expected under future climate change scenarios may cause an increase in CDOM quantity and shift in quality

  3. The origin and distribution of HAPs elements in relation to maceral composition of the A1 lignite bed (Paleocene, Calvert Bluff Formation, Wilcox Group), Calvert mine area, east-central Texas

    Science.gov (United States)

    Crowley, Sharon S.; Warwick, Peter D.; Ruppert, Leslie F.; Pontolillo, James

    1997-01-01

    The origin and distribution of twelve potentially Hazardous Air Pollutants (HAPs; As, Be, Cd, Cr, Co, Hg, Mn, Ni, Pb, Sb, Se, and U) identified in the 1990 Clean Air Act Amendments were examined in relation to the maceral composition of the A1 bed (Paleocene, Calvert Bluff Formation, Wilcox Group) of the Calvert mine in east-central Texas. The 3.2 m-thick A1 bed was divided into nine incremental channel samples (7 lignite samples and 2 shaley coal samples) on the basis of megascopic characteristics. Results indicate that As, Cd, Cr, Ni, Pb, Sb, and U are strongly correlated with ash yield and are enriched in the shaley coal samples. We infer that these elements are associated with inorganic constituents in the coal bed and may be derived from a penecontemporaneous stream channel located several kilometers southeast of the mining block. Of the HAPs elements studied, Mn and Hg are the most poorly correlated to ash yield. We infer an organic association for Mn; Hg may be associated with pyrite. The rest of the trace elements (Be, Co, and Se) are weakly correlated with ash yield. Further analytical work is necessary to determine the mode of occurrence for these elements. Overall, concentrations of the HAPs elements are generally similar to or less than those reported in previous studies of lignites of the Wilcox Group, east-central region, Texas. Petrographic analysis indicates the following ranges in composition for the seven lignite samples: liptinites (5–8%), huminites (88–95%), and inertinites (trace amounts to 7%). Samples from the middle portion of the A1 bed contain abundant crypto-eugelinite compared to the rest of the samples; this relationship suggests that the degradation of plant material was an important process during the development of the peat mire. With the exception of Hg and Mn, relatively low levels of the HAPs elements studied are found in the samples containing abundant crypto-eugelinite. We infer that the peat-forming environment for this

  4. Group X

    Energy Technology Data Exchange (ETDEWEB)

    Fields, Susannah

    2007-08-16

    This project is currently under contract for research through the Department of Homeland Security until 2011. The group I was responsible for studying has to remain confidential so as not to affect the current project. All dates, reference links and authors, and other distinguishing characteristics of the original group have been removed from this report. All references to the name of this group or the individual splinter groups has been changed to 'Group X'. I have been collecting texts from a variety of sources intended for the use of recruiting and radicalizing members for Group X splinter groups for the purpose of researching the motivation and intent of leaders of those groups and their influence over the likelihood of group radicalization. This work included visiting many Group X websites to find information on splinter group leaders and finding their statements to new and old members. This proved difficult because the splinter groups of Group X are united in beliefs, but differ in public opinion. They are eager to tear each other down, prove their superiority, and yet remain anonymous. After a few weeks of intense searching, a list of eight recruiting texts and eight radicalizing texts from a variety of Group X leaders were compiled.

  5. Cement Formation

    DEFF Research Database (Denmark)

    Telschow, Samira; Jappe Frandsen, Flemming; Theisen, Kirsten

    2012-01-01

    Cement production has been subject to several technological changes, each of which requires detailed knowledge about the high multiplicity of processes, especially the high temperature process involved in the rotary kiln. This article gives an introduction to the topic of cement, including...... an overview of cement production, selected cement properties, and clinker phase relations. An extended summary of laboratory-scale investigations on clinkerization reactions, the most important reactions in cement production, is provided. Clinker formations by solid state reactions, solid−liquid and liquid......−liquid reactions are discussed, as are the influences of particles sizes on clinker phase formation. Furthermore, a mechanism for clinker phase formation in an industrial rotary kiln reactor is outlined....

  6. Star formation

    International Nuclear Information System (INIS)

    Woodward, P.R.

    1978-01-01

    Theoretical models of star formation are discussed beginning with the earliest stages and ending in the formation of rotating, self-gravitating disks or rings. First a model of the implosion of very diffuse gas clouds is presented which relies upon a shock at the edge of a galactic spiral arm to drive the implosion. Second, models are presented for the formation of a second generation of massive stars in such a cloud once a first generation has formed. These models rely on the ionizing radiation from massive stars or on the supernova shocks produced when these stars explode. Finally, calculations of the gravitational collapse of rotating clouds are discussed with special focus on the question of whether rotating disks or rings are the result of such a collapse. 65 references

  7. Galaxy Formation

    DEFF Research Database (Denmark)

    Sparre, Martin

    Galaxy formation is an enormously complex discipline due to the many physical processes that play a role in shaping galaxies. The objective of this thesis is to study galaxy formation with two different approaches: First, numerical simulations are used to study the structure of dark matter and how...... galaxies form stars throughout the history of the Universe, and secondly it is shown that observations of gamma-ray bursts (GRBs) can be used to probe galaxies with active star formation in the early Universe. A conclusion from the hydrodynamical simulations is that the galaxies from the stateof...... is important, since it helps constraining chemical evolution models at high redshift. A new project studying how the population of galaxies hosting GRBs relate to other galaxy population is outlined in the conclusion of this thesis. The core of this project will be to quantify how the stellar mass function...

  8. Comet formation

    Science.gov (United States)

    Blum, J.

    2014-07-01

    There has been vast progress in our understanding of planetesimal formation over the past decades, owing to a number of laboratory experiments as well as to refined models of dust and ice agglomeration in protoplanetary disks. Coagulation rapidly forms cm-sized ''pebbles'' by direct sticking in collisions at low velocities (Güttler et al. 2010; Zsom et al. 2010). For the further growth, two model approaches are currently being discussed: (1) Local concentration of pebbles in nebular instabilities until gravitational instability occurs (Johansen et al. 2007). (2) A competition between fragmentation and mass transfer in collisions among the dusty bodies, in which a few ''lucky winners'' make it to planetesimal sizes (Windmark et al. 2012a,b; Garaud et al. 2013). Predictions of the physical properties of the resulting bodies in both models allow a distinction of the two formation scenarios of planetesimals. In particular, the tensile strength (i.e, the inner cohesion) of the planetesimals differ widely between the two models (Skorov & Blum 2012; Blum et al. 2014). While model (1) predicts tensile strengths on the order of ˜ 1 Pa, model (2) results in rather compactified dusty bodies with tensile strengths in the kPa regime. If comets are km-sized survivors of the planetesimal-formation era, they should in principle hold the secret of their formation process. Water ice is the prime volatile responsible for the activity of comets. Thermophysical models of the heat and mass transport close to the comet-nucleus surface predict water-ice sublimation temperatures that relate to maximum sublimation pressures well below the kPa regime predicted for formation scenario (2). Model (1), however, is in agreement with the observed dust and gas activity of comets. Thus, a formation scenario for cometesimals involving gravitational instability is favored (Blum et al. 2014).

  9. Group Flow and Group Genius

    Science.gov (United States)

    Sawyer, Keith

    2015-01-01

    Keith Sawyer views the spontaneous collaboration of group creativity and improvisation actions as "group flow," which organizations can use to function at optimum levels. Sawyer establishes ideal conditions for group flow: group goals, close listening, complete concentration, being in control, blending egos, equal participation, knowing…

  10. Permutation groups

    CERN Document Server

    Passman, Donald S

    2012-01-01

    This volume by a prominent authority on permutation groups consists of lecture notes that provide a self-contained account of distinct classification theorems. A ready source of frequently quoted but usually inaccessible theorems, it is ideally suited for professional group theorists as well as students with a solid background in modern algebra.The three-part treatment begins with an introductory chapter and advances to an economical development of the tools of basic group theory, including group extensions, transfer theorems, and group representations and characters. The final chapter feature

  11. Effectiveness of Group Supervision versus Combined Group and Individual Supervision.

    Science.gov (United States)

    Ray, Dee; Altekruse, Michael

    2000-01-01

    Investigates the effectiveness of different types of supervision (large group, small group, combined group, individual supervision) with counseling students (N=64). Analyses revealed that all supervision formats resulted in similar progress in counselor effectiveness and counselor development. Participants voiced a preference for individual…

  12. From Sermon Formation to Preacher Formation

    DEFF Research Database (Denmark)

    Gaarden, Marianne

    2016-01-01

    today is less about exercising the authority of an office and more about embodying authenticity. I argue that traditional homiletic education can benefit from implementing a learner-centered approach to teaching moving from sermon formation towards preacher formation, in order to develop and train...... preachers. This involves a learning strategy to ministry where theological skills, pastoral competences, and own personality are interwoven. Teaching here means facilitating a room of learning where teacher’s power and control is reduced, allowing the preacher to reflect upon own practice without being...... judged, evaluated, or critiqued. In this paper, I explain how a learner-centered approach to education works in practice and show how pastors experience the teaching method and the congregations’ positive response to their improvements. I shall present the results of a focus-group interview with pastors...

  13. Group devaluation and group identification

    NARCIS (Netherlands)

    Leach, C.W.; Rodriguez Mosquera, P.M.; Vliek, M.L.W.; Hirt, E.

    2010-01-01

    In three studies, we showed that increased in-group identification after (perceived or actual) group devaluation is an assertion of a (preexisting) positive social identity that counters the negative social identity implied in societal devaluation. Two studies with real-world groups used order

  14. Lie groups and algebraic groups

    Indian Academy of Sciences (India)

    We give an exposition of certain topics in Lie groups and algebraic groups. This is not a complete ... of a polynomial equation is equivalent to the solva- bility of the equation ..... to a subgroup of the group of roots of unity in k (in particular, it is a ...

  15. Estimating absorption coefficients of colored dissolved organic matter (CDOM) using a semi-analytical algorithm for southern Beaufort Sea waters: application to deriving concentrations of dissolved organic carbon from space

    Science.gov (United States)

    Matsuoka, A.; Hooker, S. B.; Bricaud, A.; Gentili, B.; Babin, M.

    2013-02-01

    A series of papers have suggested that freshwater discharge, including a large amount of dissolved organic matter (DOM), has increased since the middle of the 20th century. In this study, a semi-analytical algorithm for estimating light absorption coefficients of the colored fraction of DOM (CDOM) was developed for southern Beaufort Sea waters using remote sensing reflectance at six wavelengths in the visible spectral domain corresponding to MODIS ocean color sensor. This algorithm allows the separation of colored detrital matter (CDM) into CDOM and non-algal particles (NAP) through the determination of NAP absorption using an empirical relationship between NAP absorption and particle backscattering coefficients. Evaluation using independent datasets, which were not used for developing the algorithm, showed that CDOM absorption can be estimated accurately to within an uncertainty of 35% and 50% for oceanic and coastal waters, respectively. A previous paper (Matsuoka et al., 2012) showed that dissolved organic carbon (DOC) concentrations were tightly correlated with CDOM absorption in our study area (r2 = 0.97). By combining the CDOM absorption algorithm together with the DOC versus CDOM relationship, it is now possible to estimate DOC concentrations in the near-surface layer of the southern Beaufort Sea using satellite ocean color data. DOC concentrations in the surface waters were estimated using MODIS ocean color data, and the estimates showed reasonable values compared to in situ measurements. We propose a routine and near real-time method for deriving DOC concentrations from space, which may open the way to an estimate of DOC budgets for Arctic coastal waters.

  16. Estimating absorption coefficients of colored dissolved organic matter (CDOM using a semi-analytical algorithm for southern Beaufort Sea waters: application to deriving concentrations of dissolved organic carbon from space

    Directory of Open Access Journals (Sweden)

    A. Matsuoka

    2013-02-01

    Full Text Available A series of papers have suggested that freshwater discharge, including a large amount of dissolved organic matter (DOM, has increased since the middle of the 20th century. In this study, a semi-analytical algorithm for estimating light absorption coefficients of the colored fraction of DOM (CDOM was developed for southern Beaufort Sea waters using remote sensing reflectance at six wavelengths in the visible spectral domain corresponding to MODIS ocean color sensor. This algorithm allows the separation of colored detrital matter (CDM into CDOM and non-algal particles (NAP through the determination of NAP absorption using an empirical relationship between NAP absorption and particle backscattering coefficients. Evaluation using independent datasets, which were not used for developing the algorithm, showed that CDOM absorption can be estimated accurately to within an uncertainty of 35% and 50% for oceanic and coastal waters, respectively. A previous paper (Matsuoka et al., 2012 showed that dissolved organic carbon (DOC concentrations were tightly correlated with CDOM absorption in our study area (r2 = 0.97. By combining the CDOM absorption algorithm together with the DOC versus CDOM relationship, it is now possible to estimate DOC concentrations in the near-surface layer of the southern Beaufort Sea using satellite ocean color data. DOC concentrations in the surface waters were estimated using MODIS ocean color data, and the estimates showed reasonable values compared to in situ measurements. We propose a routine and near real-time method for deriving DOC concentrations from space, which may open the way to an estimate of DOC budgets for Arctic coastal waters.

  17. Group Work

    Science.gov (United States)

    Wilson, Kristy J.; Brickman, Peggy; Brame, Cynthia J.

    2018-01-01

    Science, technology, engineering, and mathematics faculty are increasingly incorporating both formal and informal group work in their courses. Implementing group work can be improved by an understanding of the extensive body of educational research studies on this topic. This essay describes an online, evidence-based teaching guide published by…

  18. Reflection groups

    International Nuclear Information System (INIS)

    Eggermont, G.

    2006-01-01

    In 2005, PISA organised proactive meetings of reflection groups on involvement in decision making, expert culture and ethical aspects of radiation protection.All reflection group meetings address particular targeted audiences while the output publication in book form is put forward

  19. Group theory

    CERN Document Server

    Scott, W R

    2010-01-01

    Here is a clear, well-organized coverage of the most standard theorems, including isomorphism theorems, transformations and subgroups, direct sums, abelian groups, and more. This undergraduate-level text features more than 500 exercises.

  20. Group Grammar

    Science.gov (United States)

    Adams, Karen

    2015-01-01

    In this article Karen Adams demonstrates how to incorporate group grammar techniques into a classroom activity. In the activity, students practice using the target grammar to do something they naturally enjoy: learning about each other.

  1. Computer group

    International Nuclear Information System (INIS)

    Bauer, H.; Black, I.; Heusler, A.; Hoeptner, G.; Krafft, F.; Lang, R.; Moellenkamp, R.; Mueller, W.; Mueller, W.F.; Schati, C.; Schmidt, A.; Schwind, D.; Weber, G.

    1983-01-01

    The computer groups has been reorganized to take charge for the general purpose computers DEC10 and VAX and the computer network (Dataswitch, DECnet, IBM - connections to GSI and IPP, preparation for Datex-P). (orig.)

  2. Group learning

    DEFF Research Database (Denmark)

    Pimentel, Ricardo; Noguira, Eloy Eros da Silva; Elkjær, Bente

    The article presents a study that aims at the apprehension of the group learning in a top management team composed by teachers in a Brazilian Waldorf school whose management is collective. After deciding to extend the school, they had problems recruiting teachers who were already trained based...... on the Steiner´s ideas, which created practical problems for conducting management activities. The research seeks to understand how that group of teachers collectively manage the school, facing the lack of resources, a significant heterogeneity in the relationships, and the conflicts and contradictions......, and they are interrelated to the group learning as the construction, maintenance and reconstruction of the intelligibility of practices. From this perspective, it can be said that learning is a practice and not an exceptional phenomenon. Building, maintaining and rebuilding the intelligibility is the group learning...

  3. Group technology

    International Nuclear Information System (INIS)

    Rome, C.P.

    1976-01-01

    Group Technology has been conceptually applied to the manufacture of batch-lots of 554 machined electromechanical parts which now require 79 different types of metal-removal tools. The products have been grouped into 7 distinct families which require from 8 to 22 machines in each machine-cell. Throughput time can be significantly reduced and savings can be realized from tooling, direct-labor, and indirect-labor costs

  4. Abelian groups

    CERN Document Server

    Fuchs, László

    2015-01-01

    Written by one of the subject’s foremost experts, this book focuses on the central developments and modern methods of the advanced theory of abelian groups, while remaining accessible, as an introduction and reference, to the non-specialist. It provides a coherent source for results scattered throughout the research literature with lots of new proofs. The presentation highlights major trends that have radically changed the modern character of the subject, in particular, the use of homological methods in the structure theory of various classes of abelian groups, and the use of advanced set-theoretical methods in the study of undecidability problems. The treatment of the latter trend includes Shelah’s seminal work on the undecidability in ZFC of Whitehead’s Problem; while the treatment of the former trend includes an extensive (but non-exhaustive) study of p-groups, torsion-free groups, mixed groups, and important classes of groups arising from ring theory. To prepare the reader to tackle these topics, th...

  5. Planet Formation

    Science.gov (United States)

    Podolak, Morris

    2018-04-01

    Modern observational techniques are still not powerful enough to directly view planet formation, and so it is necessary to rely on theory. However, observations do give two important clues to the formation process. The first is that the most primitive form of material in interstellar space exists as a dilute gas. Some of this gas is unstable against gravitational collapse, and begins to contract. Because the angular momentum of the gas is not zero, it contracts along the spin axis, but remains extended in the plane perpendicular to that axis, so that a disk is formed. Viscous processes in the disk carry most of the mass into the center where a star eventually forms. In the process, almost as a by-product, a planetary system is formed as well. The second clue is the time required. Young stars are indeed observed to have gas disks, composed mostly of hydrogen and helium, surrounding them, and observations tell us that these disks dissipate after about 5 to 10 million years. If planets like Jupiter and Saturn, which are very rich in hydrogen and helium, are to form in such a disk, they must accrete their gas within 5 million years of the time of the formation of the disk. Any formation scenario one proposes must produce Jupiter in that time, although the terrestrial planets, which don't contain significant amounts of hydrogen and helium, could have taken longer to build. Modern estimates for the formation time of the Earth are of the order of 100 million years. To date there are two main candidate theories for producing Jupiter-like planets. The core accretion (CA) scenario supposes that any solid materials in the disk slowly coagulate into protoplanetary cores with progressively larger masses. If the core remains small enough it won't have a strong enough gravitational force to attract gas from the surrounding disk, and the result will be a terrestrial planet. If the core grows large enough (of the order of ten Earth masses), and the disk has not yet dissipated, then

  6. Geological factors of deposit formation

    International Nuclear Information System (INIS)

    Grushevoj, G.V.

    1980-01-01

    Geologic factors of hydrogenic uranium deposit formation are considered. Structural, formation and lithological-facies factors of deposit formation, connected with zones of stratal oxidation, are characterized. Peculiarities of deposit localization, connected with orogenic structures of Mesozoic and lenozoic age, are described. It is noted that deposits of anagenous group are widely spread in Paleozoic formations, infiltration uranium deposits are localized mainly in Cenozoic sediments, while uranium mineralization both anagenous and infiltration groups are widely developed in Mesozoic sediments. Anagenous deposits were formed in non-oxygen situation, their age varies from 200 to 55 mln years. Infiltration deposit formation is determined by asymmetric oxidation zonation, their age varies from 10 - 40 mln years to dozens of thousand years [ru

  7. Group dynamics.

    Science.gov (United States)

    Scandiffio, A L

    1990-12-01

    Group dynamics play a significant role within any organization, culture, or unit. The important thing to remember with any of these structures is that they are made up of people--people with different ideas, motivations, background, and sometimes different agendas. Most groups, formal or informal, look for a leader in an effort to maintain cohesiveness of the unit. At times, that cultural bond must be developed; once developed, it must be nurtured. There are also times that one of the group no longer finds the culture comfortable and begins to act out behaviorally. It is these times that become trying for the leader as she or he attempts to remain objective when that which was once in the building phase of group cohesiveness starts to fall apart. At all times, the manager must continue to view the employee creating the disturbance as an integral part of the group. It is at this time that it is beneficial to perceive the employee exhibiting problem behaviors as a special employee, as one who needs the benefit of your experience and skills, as one who is still part of the group. It is also during this time that the manager should focus upon her or his own views in the area of power, communication, and the corporate culture of the unit that one has established before attempting to understand another's point of view. Once we understand our own motivation and accept ourselves, it is then that we may move on to offer assistance to another. Once we understand our insecurities recognizing staff dysfunction as a symptom of system dysfunction will not be so threatening to the concept of the manager that we perceive ourselves to be. It takes a secure person to admit that she or he favors staff before deciding to do something to change things. The important thing to know is that it can be done. The favored staff can find a new way of relating to others, the special employee can find new modes of behavior (and even find self-esteem in the process), the group can find new ways

  8. Galaxy Formation

    CERN Document Server

    Longair, Malcolm S

    2008-01-01

    This second edition of Galaxy Formation is an up-to-date text on astrophysical cosmology, expounding the structure of the classical cosmological models from a contemporary viewpoint. This forms the background to a detailed study of the origin of structure and galaxies in the Universe. The derivations of many of the most important results are derived by simple physical arguments which illuminate the results of more advanced treatments. A very wide range of observational data is brought to bear upon these problems, including the most recent results from WMAP, the Hubble Space Telescope, galaxy surveys like the Sloan Digital Sky Survey and the 2dF Galaxy Redshift Survey, studies of Type 1a supernovae, and many other observations.

  9. Galaxy formation

    International Nuclear Information System (INIS)

    Gribbin, J.

    1979-01-01

    The current debate on the origin and evolution of galaxies is reviewed and evidence to support the so-called 'isothermal' and 'adiabatic' fluctuation models considered. It is shown that new theories have to explain the formation of both spiral and elliptical galaxies and the reason for their differences. It is stated that of the most recent models the best indicates that rotating spiral galaxies are formed naturally when gas concentrates in the centre of a great halo and forms stars while ellipticals are explained by later interactions between spiral galaxies and merging, which can cancel out the rotation while producing an elliptical galaxy in which the stars, coming from two original galaxies, follow very elliptical, anisotropic orbits. (UK)

  10. Habit formation.

    Science.gov (United States)

    Smith, Kyle S; Graybiel, Ann M

    2016-03-01

    Habits, both good ones and bad ones, are pervasive in animal behavior. Important frameworks have been developed to understand habits through psychological and neurobiological studies. This work has given us a rich understanding of brain networks that promote habits, and has also helped us to understand what constitutes a habitual behavior as opposed to a behavior that is more flexible and prospective. Mounting evidence from studies using neural recording methods suggests that habit formation is not a simple process. We review this evidence and take the position that habits could be sculpted from multiple dissociable changes in neural activity. These changes occur across multiple brain regions and even within single brain regions. This strategy of classifying components of a habit based on different brain signals provides a potentially useful new way to conceive of disorders that involve overly fixed behaviors as arising from different potential dysfunctions within the brain's habit network.

  11. Habit formation

    Science.gov (United States)

    Smith, Kyle S.; Graybiel, Ann M.

    2016-01-01

    Habits, both good ones and bad ones, are pervasive in animal behavior. Important frameworks have been developed to understand habits through psychological and neurobiological studies. This work has given us a rich understanding of brain networks that promote habits, and has also helped us to understand what constitutes a habitual behavior as opposed to a behavior that is more flexible and prospective. Mounting evidence from studies using neural recording methods suggests that habit formation is not a simple process. We review this evidence and take the position that habits could be sculpted from multiple dissociable changes in neural activity. These changes occur across multiple brain regions and even within single brain regions. This strategy of classifying components of a habit based on different brain signals provides a potentially useful new way to conceive of disorders that involve overly fixed behaviors as arising from different potential dysfunctions within the brain's habit network. PMID:27069378

  12. Group representations

    CERN Document Server

    Karpilovsky, G

    1994-01-01

    This third volume can be roughly divided into two parts. The first part is devoted to the investigation of various properties of projective characters. Special attention is drawn to spin representations and their character tables and to various correspondences for projective characters. Among other topics, projective Schur index and projective representations of abelian groups are covered. The last topic is investigated by introducing a symplectic geometry on finite abelian groups. The second part is devoted to Clifford theory for graded algebras and its application to the corresponding theory

  13. Lego Group

    DEFF Research Database (Denmark)

    Møller Larsen, Marcus; Pedersen, Torben; Slepniov, Dmitrij

    2010-01-01

    The last years’ rather adventurous journey from 2004 to 2009 had taught the fifth-largest toy-maker in the world - the LEGO Group - the importance of managing the global supply chain effectively. In order to survive the largest internal financial crisis in its roughly 70 years of existence......, the management had, among many initiatives, decided to offshore and outsource a major chunk of its production to Flextronics. In this pursuit of rapid cost-cutting sourcing advantages, the LEGO Group planned to license out as much as 80 per cent of its production besides closing down major parts...

  14. Results of a collaborative study of the EDNAP group regarding the reproducibility and robustness of the Y-chromosome STRs DYS19, DYS389 I and II, DYS390 and DYS393 in a PCR pentaplex format

    DEFF Research Database (Denmark)

    Carracedo, A; Beckmann, A; Bengs, A

    2001-01-01

    A collaborative exercise was carried out by the European DNA Profiling Group (EDNAP) in the frame work of the STADNAP program, i.e. standardization of DNA profiling in Europe, in order to evaluate the performance of a Y-chromosome STR pentaplex, which includes the loci DYS19, DYS389 I and II, DYS...

  15. Informal groups

    NARCIS (Netherlands)

    E. van den Berg; P. van Houwelingen; J. de Hart

    2011-01-01

    Original title: Informele groepen Going out running with a group of friends, rather than joining an official sports club. Individuals who decide to take action themselves rather than giving money to good causes. Maintaining contact with others not as a member of an association, but through an

  16. Physically detached 'compact groups'

    Science.gov (United States)

    Hernquist, Lars; Katz, Neal; Weinberg, David H.

    1995-01-01

    A small fraction of galaxies appear to reside in dense compact groups, whose inferred crossing times are much shorter than a Hubble time. These short crossing times have led to considerable disagreement among researchers attempting to deduce the dynamical state of these systems. In this paper, we suggest that many of the observed groups are not physically bound but are chance projections of galaxies well separated along the line of sight. Unlike earlier similar proposals, ours does not require that the galaxies in the compact group be members of a more diffuse, but physically bound entity. The probability of physically separated galaxies projecting into an apparent compact group is nonnegligible if most galaxies are distributed in thin filaments. We illustrate this general point with a specific example: a simulation of a cold dark matter universe, in which hydrodynamic effects are included to identify galaxies. The simulated galaxy distribution is filamentary and end-on views of these filaments produce apparent galaxy associations that have sizes and velocity dispersions similar to those of observed compact groups. The frequency of such projections is sufficient, in principle, to explain the observed space density of groups in the Hickson catalog. We discuss the implications of our proposal for the formation and evolution of groups and elliptical galaxies. The proposal can be tested by using redshift-independent distance estimators to measure the line-of-sight spatial extent of nearby compact groups.

  17. Quantification of the risk of urinary calcium stone formation in the urine collected at 2 times of the day in a group of children studied to rule out prelithiasis

    Directory of Open Access Journals (Sweden)

    Víctor M. García Nieto

    2018-05-01

    Full Text Available Background: Various genetic and environmental factors are involved in urolithiasis. The 2 most common metabolic abnormalities are the increase in urinary calcium and low urinary citrate excretion. The ratio calculated between the concentrations of both substances is a good risk marker for the formation of calcium stones. Objectives: To determine whether the risk of urinary calcium stone formation changes throughout the day in the same patient. Methods: We studied 56 children (23 V, 33 M to check if they had prelithiasis. Calcium, citrate, and creatinine concentrations were determined in two urine samples collected one before dinner and the other in the morning. It was collected if they had ultrasound stones and if there was a history of urolithiasis in first and/or second degree relatives. Results: In 25 patients (44.6%, renal ultrasound was positive for lithiasis (stones [n = 9] and microlithiasis [n = 16]. Forty of the 56 families (71.4% had a history of urolithiasis. The percentage of abnormal urinary calcium (28.6% concentrations and an abnormal calcium/citrate ratio (69.6% was higher in the first urine of the day. The calcium/citrate ratio was the only studied parameter that was related to a family history of urolithiasis. There were no differences in urinary parameters between patients with and without ultrasound-confirmed kidney stones. Conclusions: Urinary concentrations of calcium and the calcium/citrate ratio vary throughout the day. Urine produced at night has a higher risk of urinary calcium stone formation. Resumen: Antecedentes: En la urolitiasis intervienen diversos factores genéticos y ambientales. Las 2 anomalías metabólicas más frecuentes son el incremento en la eliminación urinaria de calcio y la reducción en la de citrato. El cociente calculado entre las concentraciones de ambas sustancias es un buen marcador de riesgo de formación de cálculos cálcicos. Objetivos: Determinar si el riesgo litógeno en la orina de

  18. COMMUNICATIONS GROUP

    CERN Multimedia

    L. Taylor

    2011-01-01

    The CMS Communications Group, established at the start of 2010, has been busy in all three areas of its responsibility: (1) Communications Infrastructure, (2) Information Systems, and (3) Outreach and Education. Communications Infrastructure There are now 55 CMS Centres worldwide that are well used by physicists working on remote CMS shifts, Computing operations, data quality monitoring, data analysis and outreach. The CMS Centre@CERN in Meyrin, is the centre of the CMS offline and computing operations, hosting dedicated analysis efforts such as during the CMS Heavy Ion lead-lead running. With a majority of CMS sub-detectors now operating in a “shifterless” mode, many monitoring operations are now routinely performed from there, rather than in the main Control Room at P5. The CMS Communications Group, CERN IT and the EVO team are providing excellent videoconferencing support for the rapidly-increasing number of CMS meetings. In parallel, CERN IT and ...

  19. Group therapy

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    Full text: In his review 'Genesis of Unified Gauge Theories' at the symposium in Honour of Abdus Salam (June, page 23), Tom Kibble of Imperial College, London, looked back to the physics events around Salam from 1959-67. He described how, in the early 1960s, people were pushing to enlarge the symmetry of strong interactions beyond the SU(2) of isospin and incorporate the additional strangeness quantum number. Kibble wrote - 'Salam had students working on every conceivable symmetry group. One of these was Yuval Ne'eman, who had the good fortune and/or prescience to work on SU(3). From that work, and of course from the independent work of Murray Gell- Mann, stemmed the Eightfold Way, with its triumphant vindication in the discovery of the omega-minus in 1964.' Yuval Ne'eman writes - 'I was the Defence Attaché at the Israeli Embassy in London and was admitted by Salam as a part-time graduate student when I arrived in 1958. I started research after resigning from the Embassy in May 1960. Salam suggested a problem: provide vector mesons with mass - the problem which was eventually solved by Higgs, Guralnik, Kibble,.... (as described by Kibble in his article). I explained to Salam that I had become interested in symmetry. Nobody at Imperial College at the time, other than Salam himself, was doing anything in groups, and attention further afield was focused on the rotation - SO(N) - groups. Reacting to my own half-baked schemes, Salam told me to forget about the rotation groups he taught us, and study group theory in depth, directing me to Eugene Dynkin's classification of Lie subalgebras, about which he had heard from Morton Hamermesh. I found Dynkin incomprehensible without first learning about Lie algebras from Henri Cartan's thesis, which luckily had been reproduced by Dynkin in his 1946 thesis, using his diagram method. From a copy of a translation of Dynkin's thesis which I found in the British Museum Library, I

  20. COMMUNICATIONS GROUP

    CERN Multimedia

    L. Taylor

    2010-01-01

    The CMS Communications Group, established at the start of 2010, has been strengthening the activities in all three areas of its responsibility: (1) Communications Infrastructure, (2) Information Systems, and (3) Outreach and Education. Communications Infrastructure The Communications Group has invested a lot of effort to support the operations needs of CMS. Hence, the CMS Centres where physicists work on remote CMS shifts, Data Quality Monitoring, and Data Analysis are running very smoothly. There are now 55 CMS Centres worldwide, up from just 16 at the start of CMS data-taking. The latest to join are Imperial College London, the University of Iowa, and the Università di Napoli. The CMS Centre@CERN in Meyrin, which is now full repaired after the major flooding at the beginning of the year, has been at the centre of CMS offline and computing operations, most recently hosting a large fraction of the CMS Heavy Ion community during the lead-lead run. A number of sub-detector shifts can now take pla...

  1. COMMUNICATIONS GROUP

    CERN Multimedia

    L. Taylor

    2011-01-01

    The CMS Communications Group has been busy in all three areas of its responsibility: (1) Communications Infrastructure, (2) Information Systems, and (3) Outreach and Education. Communications Infrastructure The 55 CMS Centres worldwide are well used by physicists working on remote CMS shifts, Computing operations, data quality monitoring, data analysis and outreach. The CMS Centre@CERN in Meyrin, is the centre of the CMS Offline and Computing operations, and a number of subdetector shifts can now take place there, rather than in the main Control Room at P5. A new CMS meeting room has been equipped for videoconferencing in building 42, next to building 40. Our building 28 meeting room and the facilities at P5 will be refurbished soon and plans are underway to steadily upgrade the ageing equipment in all 15 CMS meeting rooms at CERN. The CMS evaluation of the Vidyo tool indicates that it is not yet ready to be considered as a potential replacement for EVO. The Communications Group provides the CMS-TV (web) cha...

  2. Microevolution of human archaic groups of Arica, northern Chile, and its genetic contribution to populations from the Formative Period Microevolución de grupos humanos arcaicos de Arica, norte de Chile, y su contribución genética a las poblaciones del Período Formativo

    Directory of Open Access Journals (Sweden)

    HÉCTOR HUGO VARELA

    2006-06-01

    Full Text Available The microevolution of the archaic populations from Chile's northern coast and its morphological contribution to Formative period groups was studied. The sample comprised 181 individuals belonging to two Archaic (Morro-Uhle and Morro 1-1/6 and one Formative (Playa Miller-7 [Plm-7] series of the coast and one sample from the Formative (Alto Ramírez exhumed at the Azapa Valley. A total of 29 metric variables of the cranium were analyzed. Biological variability was assessed using discriminant analysis and Mahalanobis' D² distance stadistic (MDS. Population structure was inferred using a method based on quantitative genetic theory that predicts a lineal relationship between average within-group phenotypic variance and group distance to the population centroid. The four samples studied proved to be different from a morphologic point of view. The greatest distance was observed between Plm-7 (coast Formative and Alto Ramirez (valley Formative, the least between Morro-Uhle and Morro 1-1/6, the remaining distances presenting intermediate values. Regarding the total population, the most divergent group was Alto Ramírez and the least divergent was Morro1-1/6. A gradual biologic change was observed between Archaic (Morro Uhle and Morro 1-1/6 and coastal Formative populations (Plm-7 pointing to a morphological (genetic contribution of Archaic fishermen to Formative population of Chile's northern coast, without excluding gene flow from other groups of the South Central Andean AreaEstudiamos la microevolución de las poblaciones arcaicas de la costa norte y sus contribuciones morfológicas al Período Formativo. La muestra comprendió 181 individuos pertenecientes a dos colecciones arcaicas de la costa (Morro-Uhle y Morro 1-1/6 y una al formativo (Alto Ramírez exhumada en el Valle de Azapa. Un total de 29 variables métricas del cráneo fueron analizadas. La variabilidad biológica fue determinada utilizando análisis discriminante y distancias de

  3. Chemostratigraphy of Neoproterozoic Banded Iron Formation (BIF)

    DEFF Research Database (Denmark)

    Gaucher, Claudio; Sial, Alcides N.; Frei, Robert

    2015-01-01

    Sawawin BIF (Saudi Arabia), and the Jucurutu Formation of the Seridó Belt (NE Brazil). Lake Superior type BIFs are represented by the Tonian Shilu Group (South China) and the late Ediacaran Arroyo del Soldado Group (Yerbal and Cerro Espuelitas formations, Uruguay). Useful chemostratigraphic tools...

  4. COMMUNICATIONS GROUP

    CERN Multimedia

    L. Taylor

    2010-01-01

    The recently established CMS Communications Group, led by Lucas Taylor, has been busy in all three of its main are areas of responsibility: Communications Infrastructure, Information Systems, and Outreach and Education Communications Infrastructure The damage caused by the flooding of the CMS Centre@CERN on 21st December has been completely repaired and all systems are back in operation. Major repairs were made to the roofs, ceilings and one third of the floor had to be completely replaced. Throughout these works, the CMS Centre was kept operating and even hosted a major press event for first 7 TeV collisions, as described below. Incremental work behind the scenes is steadily improving the quality of the CMS communications infrastructure, particularly Webcasting, video conferencing, and meeting rooms at CERN. CERN/IT is also deploying a pilot service of a new videoconference tool called Vidyo, to assess whether it might provide an enhanced service at a lower cost, compared to the EVO tool currently in w...

  5. COMMUNICATIONS GROUP

    CERN Multimedia

    L. Taylor

    2011-01-01

    Communications Infrastructure The 55 CMS Centres worldwide are well used by physicists working on remote CMS shifts, Computing operations, data quality monitoring, data analysis and outreach. The CMS Centre@CERN in Meyrin is particularly busy at the moment, hosting about 50 physicists taking part in the heavy-ion data-taking and analysis. Three new CMS meeting room will be equipped for videoconferencing in early 2012: 40/5B-08, 42/R-031, and 28/S-029. The CMS-TV service showing LHC Page 1, CMS Page 1, etc. (http://cmsdoc.cern.ch/cmscc/projector/index.jsp) is now also available for mobile devices: http://cern.ch/mcmstv. Figure 12: Screenshots of CMS-TV for mobile devices Information Systems CMS has a new web site: (http://cern.ch/cms) using a modern web Content Management System to ensure content and links are managed and updated easily and coherently. It covers all CMS sub-projects and groups, replacing the iCMS internal pages. It also incorporates the existing CMS public web site (http:/...

  6. COMMUNICATIONS GROUP

    CERN Multimedia

    L. Taylor

    2012-01-01

      Outreach and Education We are fortunate that our research has captured the public imagination, even though this inevitably puts us under the global media spotlight, as we saw with the Higgs seminar at CERN in December, which had 110,000 distinct webcast viewers. The media interest was huge with 71 media organisations registering to come to CERN to cover the Higgs seminar, which was followed by a press briefing with the DG and Spokespersons. This event resulted in about 2,000 generally positive stories in the global media. For this seminar, the CMS Communications Group prepared up-to-date news and public material, including links to the CMS results, animations and event displays [http://cern.ch/go/Ch8thttp://cern.ch/go/Ch8t]. There were 44,000 page-views on the CMS public website, with the Higgs news article being by far the most popular item. CMS event displays from iSpy are fast becoming the iconic media images, featuring on numerous major news outlets (BBC, CNN, MSN...) as well as in the sci...

  7. Common Group Problems: A Field Study.

    Science.gov (United States)

    Weinberg, Sanford B.; And Others

    1981-01-01

    A field study of a naturally functioning group (N=125) was conducted to identify common group problems. Trained observers attended group meetings and described the problems encountered. Difficulties of cohesion, leadership, sub-group formation, and personality conflict were identified. (RC)

  8. Group percolation in interdependent networks

    Science.gov (United States)

    Wang, Zexun; Zhou, Dong; Hu, Yanqing

    2018-03-01

    In many real network systems, nodes usually cooperate with each other and form groups to enhance their robustness to risks. This motivates us to study an alternative type of percolation, group percolation, in interdependent networks under attack. In this model, nodes belonging to the same group survive or fail together. We develop a theoretical framework for this group percolation and find that the formation of groups can improve the resilience of interdependent networks significantly. However, the percolation transition is always of first order, regardless of the distribution of group sizes. As an application, we map the interdependent networks with intersimilarity structures, which have attracted much attention recently, onto the group percolation and confirm the nonexistence of continuous phase transitions.

  9. Secure Group Formation Protocol for a Medical Sensor Network Prototype

    DEFF Research Database (Denmark)

    Andersen, Jacob

    2009-01-01

    , and experience from user workshops and observations of clinicians at work on a hospital ward show that if the security mechanisms are not well designed, the technology is either rejected altogether, or they are circumvented leaving the system wide open to attacks. Our work targets the problem of designing......Designing security mechanisms such as privacy and access control for medical sensor networks is a challenging task; as such systems may be operated very frequently, at a quick pace, and at times in emergency situations. Understandably, clinicians hold extra unproductive tasks in low regard...... wireless sensors to be both secure and usable by exploring different solutions on a fully functional prototype platform. In this paper, we present an Elliptic Curve Cryptography (ECC) based protocol, which offers fully secure sensor set-up in a few seconds on standard (Telos) hardware. We evaluate...

  10. Secure Group Formation Protocol for a Medical Sensor Network Prototype

    DEFF Research Database (Denmark)

    Andersen, Jacob

    2009-01-01

    , and experience from user workshops and observations of clinicians at work on a hospital ward show that if the security mechanisms are not well designed, the technology is either rejected altogether, or they are circumvented leaving the system wide open to attacks. Our work targets the problem of designing...

  11. the interaction of gender, group formation, mobility and age

    African Journals Online (AJOL)

    Global Journal

    women point to a potential for sharing within and between families and villages. Rural urban ... there is no alternative to having good quality produce but practice local innovations in the main. In conclusion ... develop IPM innovations are at the core of the work ...... innovations; women must be empowered to do so through ...

  12. Formation Tracking with Orientation Convergence for Groups of Unicycles

    Directory of Open Access Journals (Sweden)

    Jaime González-Sierra

    2013-03-01

    Full Text Available This paper presents three trajectory tracking control strategies for unicycle-type robots based on a leader-followers scheme. The leader robot converges asymptotically to a smooth trajectory, while the follower robots form an undirected open-chain configuration at the same time. It is also shown that the orientation angles of all the robots converge to the same value. The control laws are based on a dynamic extension of the kinematic model of each robot. The output function to be controlled is the midpoint of the wheel axis of every robot. This choice leads to an ill-defined control law when the robot is at rest. To avoid such singularities, a complementary control law is enabled momentarily when the linear velocity of the unicycles is close to zero. Finally, numerical simulations and real-time experiments show the performance of the control strategies.

  13. Trace fossils from Bhuban Formation, Surma Group (Lower to ...

    Indian Academy of Sciences (India)

    dwelling and feeding activities of the infaunal organisms. ... Table 1. Lithostratigraphic classification of the Tertiary rocks of the Mizoram (modified after Karunakaran 1974 and Ganju. 1975). .... O. irregularie which could be genetically related.

  14. Improving of the Drones Group Control System

    Directory of Open Access Journals (Sweden)

    Tatiana Yurievna Morozova

    2015-05-01

    Full Text Available The article deals with the problem of drone group control, in particular, the problem of formation damage drone ensure safe movement of the group. To solve this problem is proposed to use multi-agent approach to the implementation of the overall strategy of management and metric routing algorithm for communication and the formation of the group. In general, the action of the control algorithms are shown and controlled drones in the formation of groups and roles. The conditions for the safe distance of the drone relative to each other in the group. It is shown that the combined use of these mechanisms can improve the efficiency of group management drone resistance groups to failures and failures, resulting in an increased probability of the assignment.

  15. Rates of star formation

    International Nuclear Information System (INIS)

    Larson, R.B.

    1977-01-01

    It is illustrated that a theoretical understanding of the formation and evolution of galaxies depends on an understanding of star formation, and especially of the factors influencing the rate of star formation. Some of the theoretical problems of star formation in galaxies, some approaches that have been considered in models of galaxy evolution, and some possible observational tests that may help to clarify which processes or models are most relevant are reviewed. The material is presented under the following headings: power-law models for star formation, star formation processes (conditions required, ways of achieving these conditions), observational indications and tests, and measures of star formation rates in galaxies. 49 references

  16. Why adult formation

    Directory of Open Access Journals (Sweden)

    Andrej Justinek

    1997-01-01

    Full Text Available The article argues that the primary aim of adult formation is comprehensive personality development which is supposed to ensure quality existence in modern world. The article also suggests that formarion is a permanent process. Justinek puts special emphasis on adult formation methodology and defines fundamental formation styles which encourage independent action in individuals. Justinek differentiates between formation and education. methods and concludes that formation methods are related to the emotional sphere of personality, and education methods mostly to the rational. Justinek believes that formation of adults is based primarily on appropriate formation methodology.

  17. Formate Formation and Formate Conversion in Biological Fuels Production

    Directory of Open Access Journals (Sweden)

    Bryan R. Crable

    2011-01-01

    Full Text Available Biomethanation is a mature technology for fuel production. Fourth generation biofuels research will focus on sequestering CO2 and providing carbon-neutral or carbon-negative strategies to cope with dwindling fossil fuel supplies and environmental impact. Formate is an important intermediate in the methanogenic breakdown of complex organic material and serves as an important precursor for biological fuels production in the form of methane, hydrogen, and potentially methanol. Formate is produced by either CoA-dependent cleavage of pyruvate or enzymatic reduction of CO2 in an NADH- or ferredoxin-dependent manner. Formate is consumed through oxidation to CO2 and H2 or can be further reduced via the Wood-Ljungdahl pathway for carbon fixation or industrially for the production of methanol. Here, we review the enzymes involved in the interconversion of formate and discuss potential applications for biofuels production.

  18. Individuality and social influence in groups : Inductive and deductive routes to group identity

    NARCIS (Netherlands)

    Postmes, T; Spears, R; Lee, AT; Novak, RJ

    2005-01-01

    A distinction between forms of social identity formation in small interactive groups is investigated. In groups in which a common identity is available or given, norms for individual behavior may be deduced; from group properties (deductive identity). In groups in which interpersonal relations are

  19. Which finite simple groups are unit groups?

    DEFF Research Database (Denmark)

    Davis, Christopher James; Occhipinti, Tommy

    2014-01-01

    We prove that if G is a finite simple group which is the unit group of a ring, then G is isomorphic to either (a) a cyclic group of order 2; (b) a cyclic group of prime order 2^k −1 for some k; or (c) a projective special linear group PSLn(F2) for some n ≥ 3. Moreover, these groups do all occur a...

  20. Formative assessment: a student perspective.

    Science.gov (United States)

    Hill, D A; Guinea, A I; McCarthy, W H

    1994-09-01

    An educator's view would be that formative assessment has an important role in the learning process. This study was carried out to obtain a student perspective of the place of formative assessment in the curriculum. Final-year medical students at Royal Prince Alfred Hospital took part in four teaching sessions, each structured to integrate teaching with assessment. Three assessment methods were used; the group objective structured clinical examination (G-OSCE), structured short answer (SSA) questions and a pre/post-test multiple choice questionnaire (MCQ). Teaching sessions were conducted on the subject areas of traumatology, the 'acute abdomen', arterial disorders and cancer. Fifty-five students, representing 83% of those who took part in the programme, responded to a questionnaire where they were asked to rate (on a 5-point Likert scale) their response to general questions about formative assessment and 13 specific questions concerning the comparative value of the three assessment modalities. Eighty-nine per cent of respondents felt that formative assessment should be incorporated into the teaching process. The SSA assessment was regarded as the preferred modality to reinforce previous teaching and test problem-solving skills. The MCQ was the least favoured assessment method. The effect size variable between the total scores for the SSA and MCQ was 0.64. The variable between G-OSCE and SSA/MCQ was 0.26 and 0.33 respectively. Formative assessment is a potentially powerful method to direct learning behaviour. Students should have input into the methods used.