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Sample records for 5-0 kyr bp

  1. GCM simulations of the climate of 6 kyr BP: Mean changes and interdecadal variability

    SciTech Connect

    Hewitt, C.D.; Mitchell, J.F.B.

    1996-12-01

    A simulation of the climate for 6 kyr BP, using the Hadley Centre`s atmospheric GCM with prescribed SSTs is described. The control simulation successfully reproduces the large-scale features of the present-day climate and has realistic atmospheric interannual variability. The anomaly simulation for 6 kyr BP produces a climate with an enhanced Northern Hemisphere seasonal cycle, and, in particular, a strengthened African-Asian summer monsoon. Integrated over the full annual cycle, the land surface of the southern Tropics dries while the northern Tropics get wetter, and the high northern latitudes also dry. The model simulates large regional interdecadal differences in the response at 6 kyr BP highlighting the need to allow for and account for variability on long, that is, at least decadal, timescales. The authors describe the consequences of part of the experimental design employed, whereby the SSTs for the 6 kyr BP simulation are the same as in the control as recommended by the Paleoclimate Modelling Intercomparison Project, in particular, the potential importance of ocean and sea ice feedbacks. 49 refs., 14 figs., 4 tabs.

  2. Constraint on the penultimate glacial maximum Northern Hemisphere ice topography (≈140 kyrs BP)

    NASA Astrophysics Data System (ADS)

    Colleoni, Florence; Wekerle, Claudia; Näslund, Jens-Ove; Brandefelt, Jenny; Masina, Simona

    2016-04-01

    The penultimate glacial maximum (PGM, ≈140 kyrs BP), is known to be the most extensive glaciation on record that occurred during the last 400 kyrs over Eurasia. We used a coupled Atmosphere-Ocean-Sea-Ice-Land model to simulate the climate of the PGM accounting for a reconstruction of the large PGM Eurasian ice sheet. Due to uncertainties in the PGM Laurentide ice-sheet topography, two simulations with different ice-sheet topographies over North America (large as for the Last Glacial Maximum, LGM and small as for 13 kyrs BP) are performed. Results show that the simulated PGM glacial maximum climates are of comparable magnitude with previous simulations of the LGM in both cases. Assuming a small Laurentide ice-sheet instead of the LGM one in our PGM simulations results in a shift in the planetary waves. This causes an increase in storm track activity over the North Atlantic as well as higher temperatures and precipitation rates over North America, North Atlantic and over the Eurasian ice sheet. In addition, it induces a negative temperature anomaly over East Siberia yielding a thick snow cover, which seems to be in agreement with data from recent Arctic campaigns suggesting that an ice cap developed over Beringia during the PGM. All together, the changes in large-scale circulation and regional climate simulated using a small Laurentide ice sheet match the proxies well. Based on our findings, we suggest that the Laurentide ice sheet might have been smaller during the PGM than during the LGM, in turn also implying a larger Eurasian ice sheet than during the LGM, which is supported by various geological evidence of the PGM.

  3. Analysis of African climate variability at pre-industrial, 4kyr and 6kyr BP simulations by Self-Organizing Maps

    NASA Astrophysics Data System (ADS)

    Gueye, Abdou Karim; Janicot, Serge; Braconnot, Pascale; Hely-Alleaume, Christelle; Lezine, Anne Marie

    2013-04-01

    Results from three simulations of the IPSL-CM5A (96 x 96) coupled ocean-atmosphere model from the modern pre-industrial control (1000-year long) and mid-Holocene at 4kyr (400-year long) and 6kyr (910-year long) BP have been used to investigate changes in the seasonal sub-Saharan rainfall patterns and their links with sea surface temperatures (SST) of the main oceanic basins. Self-organizing maps and hierarchical ascendant classifications have been performed over the whole data set to highlight the main rainfall anomaly patterns ("monsoon regimes") for each season of the year. Then, composite maps of SST, mean sea level pressure and low-levels wind anomalies, have been computed for every class of rainfall anomaly patterns. In northern summer, eight monsoon regimes are defined. Three of them are mostly present in the pre-industrial period, other three in the 6kyr period, and the last two are evenly distributed in the three periods. On the other hand, the 4kyr period is scattered within all the eight monsoon regimes. A discriminant analysis shows that these eight regimes can be well differentiated by the main SST modes of the oceanic basins, in particular the Guinea gulf and the Mediterranean basin. Similar analyses have been conducted for the other seasons and will be presented too. This work has been funded by the French Agency for National Research through the research project C3A.

  4. Sea Ice Variability in the Northern North Atlantic during the Last 14 Kyr BP

    NASA Astrophysics Data System (ADS)

    Cabedo-Sanz, P.; Belt, S. T.

    2014-12-01

    Sea ice plays an important role on the Earth's climate system by controlling fluxes of heat and moisture across the ocean-atmosphere interface and changes in the Earth's albedo, as well as oceanic circulation processes (e.g. the thermohaline circulation). Thus, reconstruction of Arctic sea ice is necessary to understand past sea ice variability and help improve the accuracy of model-based estimates of future changes in climate. Recently, the presence of the sea ice diatom biomarker IP25in Arctic marine sediments has been used as a proxy for past spring sea ice occurrence and as an indicator of wider palaeoenvironmental conditions for different regions of the Arctic over various timescales (e.g. Belt and Müller, 2013). Here, we present and compare new and existing biomarker data from different sediment cores along a S-N transect on the Norwegian - Svalvard continental margin from ca. 69 ºN to 78.5 ºN, northern North Atlantic. The presence and abundances of the sea ice biomarker IP25, a related HBI Diene and various sterols (e.g. brassicasterol, 24-methylenecholesterol) were used to infer past variations of sea ice/open-water conditions in the study area during the last 14 kyr BP. In addition, a comparison with other commonly used proxies for reconstructing different palaeoenvironmental conditions (e.g. planktic and benthic foraminiferal fauna, SST, IRD) was used to enable a more comprehensive reconstruction of climatic variations. References Belt, S.T., Müller, J., 2013. The Arctic sea ice biomarker IP25: a review of current understanding, recommendations for future research and applications in palaeo sea ice reconstructions. Quaternary Science Reviews 79, 9-25.

  5. Volcanic synchronisation between the EPICA Dome C and Vostok ice cores (Antarctica) 0-145 kyr BP

    NASA Astrophysics Data System (ADS)

    Parrenin, F.; Petit, J.-R.; Masson-Delmotte, V.; Wolff, E.; Basile-Doelsch, I.; Jouzel, J.; Lipenkov, V.; Rasmussen, S. O.; Schwander, J.; Severi, M.; Udisti, R.; Veres, D.; Vinther, B. M.

    2012-06-01

    This study aims at refining the synchronisation between the EPICA Dome C (EDC) and Vostok ice cores in the time interval 0-145 kyr BP by using the volcanic signatures. 102 common volcanic events were identified by using continuous electrical conductivity (ECM), di-electrical profiling (DEP) and sulfate measurements while trying to minimize the distortion of the glaciological chronologies. This is an update and a continuation of previous works performed over the 0-45 kyr interval that provided 56 tie points to the ice core chronologies (Udisti et al., 2004). This synchronisation will serve to establish Antarctic Ice Core Chronology 2012, the next synchronised Antarctic dating. A change of slope in the EDC-depth/Vostok-depth diagram is probably related to a change of accumulation regime as well as to a change of ice thickness upstream of the Lake Vostok, but we did not invoke any significant temporal change of surface accumulation at EDC relative to Vostok. No significant phase difference is detected between the EDC and Vostok isotopic records, but depth shifts between the Vostok 3G and 5G ice cores prevent from looking at this problem accurately. Three possible candidates for the Toba volcanic super-eruption ~73 kyr ago are suggested in the Vostok and EDC volcanic records. Neither the ECM, DEP nor the sulfate fingerprints for these 3 events are significantly larger than many others in the records.

  6. A complete terrestrial radiocarbon record for 11.2 to 52.8 kyr B.P.

    PubMed

    Bronk Ramsey, Christopher; Staff, Richard A; Bryant, Charlotte L; Brock, Fiona; Kitagawa, Hiroyuki; van der Plicht, Johannes; Schlolaut, Gordon; Marshall, Michael H; Brauer, Achim; Lamb, Henry F; Payne, Rebecca L; Tarasov, Pavel E; Haraguchi, Tsuyoshi; Gotanda, Katsuya; Yonenobu, Hitoshi; Yokoyama, Yusuke; Tada, Ryuji; Nakagawa, Takeshi

    2012-10-19

    Radiocarbon ((14)C) provides a way to date material that contains carbon with an age up to ~50,000 years and is also an important tracer of the global carbon cycle. However, the lack of a comprehensive record reflecting atmospheric (14)C prior to 12.5 thousand years before the present (kyr B.P.) has limited the application of radiocarbon dating of samples from the Last Glacial period. Here, we report (14)C results from Lake Suigetsu, Japan (35°35'N, 135°53'E), which provide a comprehensive record of terrestrial radiocarbon to the present limit of the (14)C method. The time scale we present in this work allows direct comparison of Lake Suigetsu paleoclimatic data with other terrestrial climatic records and gives information on the connection between global atmospheric and regional marine radiocarbon levels.

  7. Impact of climate variability on terrestrial environment in Western Europe between 45 and 9 kyr cal. BP: vegetation dynamics recorded by the Bergsee Lake (Black Forest, Germany).

    NASA Astrophysics Data System (ADS)

    Duprat-Oualid, Fanny; Begeot, Carole; Rius, Damien; Millet, Laurent; Magny, Michel

    2016-04-01

    Between 9 and 45 kyr cal. BP, two great transitions lead the global climate system to evolve from the Last-Glacial period (115-14.7 kyr cal. BP), to two successive warmer periods, the Late-Glacial Interstadial (14.7-11.7 kyr cal. BP) and the Holocene (11.7-0 kyr cal. BP). δ18O variations recorded in Greenland ice cores (GRIP & NGRIP) revealed high frequency climate variability within the Last Glacial. These reference isotopic records highlighted a succession of centennial-to-millennial warm/cold events, the so-called Greenland Interstadials (GI) and Greenland Stadials (GS). The number continental records about the period 14.7-0 kyr cal. BP is substantial. This allowed to understand the vegetation dynamics in response to climate changes this period at the North-Atlantic scale. However, sequences covering the glacial period (beyond 20 kyr cal.BP) remain rare, because of hiatuses mostly due to local glaciers. Therefore, sedimentary continuous records of vegetation dynamics are still needed to better understand climate changes during the Last Glacial in Western Europe (Heiri et al. 2014). Here we present a new high-resolution pollen record from Lake Bergsee (47°34'20''N, 7°56'11''E, 382 m a.s.l). This lake is located south of Black Forest and north of the Alps, beyond the zone of glaciers maximal extension. Therefore it could have recorded the whole last climatic cycle, i.e. 120-0 kyr cal. BP. In 2013, a 29 m long core was extracted from the Bergsee. According to the depth-age model based on 14C AMS dating and the Laacher See Tephra (LST), the record spans continuously at least the last 45 kyrs. The first series of pollen analysis, focused on the 45-9 kyr cal. BP time window, allows us to reconstruct a precise, faithful and continuous vegetation history at the centennial scale. This high temporal resolution enabled to assess the response of vegetation to secular climate events (e.g. GI-4 = 200 yrs). First, our results show that vegetation responded to climate

  8. Multiproxy Records of Indo-Pacific Climate and Environmental Change from Lake Towuti, Indonesia, Since 60 Kyr BP

    NASA Astrophysics Data System (ADS)

    Russell, J. M.; Vogel, H.; Bijaksana, S.; Konecky, B. L.; Wicaksono, S. A.; Costa, K.; Wattrus, N. J.; Melles, M.

    2014-12-01

    Lake Towuti is a large tectonic lake in central Sulawesi, Indonesia that provides a unique opportunity to reconstruct climate and terrestrial environments in the heart of the Indo-Pacific warm pool. Long-term climate variations in this region are governed by a complex interplay between the Australasian monsoons and the ENSO system forced by changing insolation, sea level, ice sheets, and greenhouse gas concentrations. Existing reconstructions suggest heterogeneous responses of Indonesian climate to these forcings, highlighting the need for new long records of regional hydrology. We have developed multiproxy datasets from Lake Towuti and nearby lakes that provide continuous, detailed, and reproducible paleoenvironmental records spanning the past 60 kyr BP. Elemental tracers of terrestrial runoff and compound-specific stable isotope records of vegetation show that wet conditions and rainforest ecosystems persisted during Marine Isotope Stage 3 and the Holocene, and were interrupted by severe drying between 33 and 15 kyr BP when high-latitude ice sheets expanded and global temperatures cooled. This chronology of change implies that central Indonesian hydroclimate varies strongly in response to high-latitude climate forcing. New vegetation records from nearby lakes confirm these findings, but suggest the amplitude of glacial-interglacial changes in vegetation were weaker at high altitude, with important implications for the heterogeneity among Indonesian climate reconstructions. New lithologic and trace element records from Lake Towuti further document the significance of climate changes at the MIS3, 2, and 1 boundaries to Lake Towuti's paleolimnology, heat budget, and seasonal mixing. High-resolution seismic reflection data from Lake Towuti constrain the maximum depth of lake level lowstands during MIS2. Hydrological modeling suggests that precipitation was reduced by at least 50% at that time, an amplitude at or above the upper limits of precipitation changes

  9. Bottom water variability in the subtropical northwestern Pacific from 26 kyr BP to present based on Mg / Ca and stable carbon and oxygen isotopes of benthic foraminifera

    NASA Astrophysics Data System (ADS)

    Kubota, Y.; Kimoto, K.; Itaki, T.; Yokoyama, Y.; Miyairi, Y.; Matsuzaki, H.

    2015-06-01

    To understand bottom water variability in the subtropical northwestern Pacific, bottom water temperatures (BWTs), carbon isotopes (δ13C), and oxygen isotopes of seawater (δ18Ow) at a water depth of 1166 m were reconstructed from 26 kyr BP to present. A new regional Mg / Ca calibration for the benthic foraminifera Cibicidoides wuellerstorfi (type B) was established to convert the benthic Mg / Ca value to BWT, based on 26 surface sediment samples and two core-top samples retrieved around Okinawa Island. During the Last Glacial Maximum (LGM), the δ18Ow in the intermediate water in the northwestern South Pacific was ~0.4‰ lower than in the deep South Pacific, indicating a greater vertical salinity gradient than at present. This salinity (and probably density) structure would have led to stratification in the intermediate and deep Pacific, which would, in turn, have greatly influenced carbon storage during the glacial time. The benthic Mg / Ca and δ18Ow records suggest changes that seem to follow Heinrich event 1 (H1) and the Bølling-Alleød (B/A) and Younger Dryas (YD) intervals, with BWT higher during H1 (~17 kyr BP) and YD (~12 kyr BP) and lower during B/A (~14 kyr BP). The warming in the bottom water during H1 suggests increased contribution of North Pacific Intermediate Water (NPIW) to the subtropical northwestern Pacific and decreased upwelling of cooler waters from the abyssal North Pacific. During the interval from 17 to 14.5 kyr BP, the BWT tended to decrease successively in association with a decrease in δ13C values, presumably as a result of increased upwelling of the abyssal waters to the intermediate depths of the North Pacific caused by shoaling and enhancement of the southward return flow of Pacific Deep Water (PDW). During the Holocene, the millennial- to sub-millennial-scale variations in the BWT generally correlate with the sea surface temperatures in the Okhotsk Sea, the source region of the NPIW, suggesting that changes in the BWT are linked

  10. Distal deltaic deposits document hydrological variability during the past 30 kyrBP in Lake Towuti, Indonesia

    NASA Astrophysics Data System (ADS)

    Vogel, Hendrik; Russell, James M.; Yudawati Cahyarini, Sri; Bijaksana, Satria; Wattrus, Nigel; Rethemeyer, Janet; Melles, Martin

    2014-05-01

    Lake Towuti (2.75°S, 121.5°E; 318 m a.s.l.) is a, 560 km2, 200-m deep tectonic lake at the downstream end of the Malili lake system, a set of five, ancient (1-2 MYr) tectonic lakes in central Sulawesi, Indonesia. The Mahalona River constitutes the largest tributary and connects Lake Towuti with the two upstream lakes Matano and Mahalona. The Mahalona River Delta is prograding into the >200m deep northern basin of Lake Towuti. Tracing past variability of Mahalona River discharge is therefore an important puzzle piece for the understanding of depositional dynamics in Lake Towuti as well as catchment hydrology and hydrological connectivity between the Malili Lakes. Distal deltaic deposits can help identifying past variability in river discharge and delta dynamics. Using highly resolved seismic reflection data collected between 2007-2013 we identified a stack of acoustically laminated reflections in Towuti's extensive and morphologically flat deep northern basin. For detailed characterization of these acoustic features we collected a c. 20m long piston core from the basin centre at 200 m water depth reaching back to c. 30 kyrBP. Sediments in this piston core consist to 75% of mass wasting deposits (MWD) of variable thickness that are intercalated with pelagic muds (25%). MWD appear mostly homogenous (silt- to finesand-sized siliciclastics with high amounts of terrestrial plant macrofossils) with only thin (1-3 cm) basal sand layers and clay caps (<1 cm). Pelagic muds appear as thin to medium bedded slightly silty clays that are clearly distinguishable from MWD. The position of MWD identified in our piston core nicely correlates with acoustically laminated reflections identified in seismic profiles crossing the coring site. Based on these combined sedimentological and acoustic datasets we interpret MWD in Towuti's northern basin as distal deltaic deposits originating from the Mahalona River Delta. Frequencies and percentages (in terms of lithofacies contribution) of

  11. Revision of Ernst Antevs' New England Varve Chronology: A Record of Meltwater Production and Southeastern LIS Recession: 18.2-12.5 kyr BP (Invited)

    NASA Astrophysics Data System (ADS)

    Ridge, J. C.

    2013-12-01

    New varve cores and 54 radiocarbon ages, have allowed the correction, closure of a gap, calibration, and expansion of Ernst Antevs' (1922) New England Varve Chronology from sediments of glacial Lake Hitchcock and it's successors in the Connecticut Valley of western New England (northeastern U.S.A.). The continuous 5659-yr chronology (18.2-12.5 kyr BP) has been renumbered as the North American Varve Chronology. Glacial varve thickness (18.2-13.7 kyr BP) documents abrupt changes in meltwater production related to varying ablation rate (summer climate) that is linked to ice sheet recession rates and advances, i.e. cold intervals are times of thin varves and slower ice recession or glacial readvances. To take advantage of the varve-climate relationship it is necessary to identify non-climatic events that can cause varve thickness to change. This includes sudden changes in lake level and flood events triggered by the abrupt drainage of tributary glacial lakes. A chronology of ice recession for intervals terminated by four stillstands and readvances of 1-2 century durations have been determined for the Connecticut Valley (from S to N): 50-100 m/yr in northern Connecticut to southern Massachusetts; Chicopee Readvance; 30-40 m/yr in central Mass.; Hatfield event; 80-90 m/yr from northern Mass. to central New Hampshire; North Charlestown end moraines; 300 m/yr to northern N.H.; Littleton Readvance; >300 m/yr to Quebec. Meltwater produced by ice recession of 300 m/yr modeled as a receding 1-bar ice sheet profile (from 100 km up ice near ELA to margin, valley width of 80 km, glacier flow rate of 200 m/yr at ELA) would be a minimum glacial meltwater discharge in the Connecticut Valley of ~90 x 109 m3/yr. This is ~10X the modern Conn. River discharge at Walpole, NH compressed almost entirely to the melt season. Non-glacial varves deposited after ice receded from the basin (13.7-12.5 kyr BP) also document climate change as a result of varve thickness varying with changes in

  12. Relative sea-level data from southwest Scotland constrain meltwater-driven sea-level jumps prior to the 8.2 kyr BP event

    NASA Astrophysics Data System (ADS)

    Lawrence, Thomas; Long, Antony J.; Gehrels, W. Roland; Jackson, Luke P.; Smith, David E.

    2016-11-01

    The most significant climate cooling of the Holocene is centred on 8.2 kyr BP (the '8.2 event'). Its cause is widely attributed to an abrupt slowdown of the Atlantic Meridional Overturning Circulation (AMOC) associated with the sudden drainage of Laurentide proglacial Lakes Agassiz and Ojibway, but model simulations have difficulty reproducing the event with a single-pulse scenario of freshwater input. Several lines of evidence point to multiple episodes of freshwater release from the decaying Laurentide Ice Sheet (LIS) between ∼8900 and ∼8200 cal yr BP, yet the precise number, timing and magnitude of these events - critical constraints for AMOC simulations - are far from resolved. Here we present a high-resolution relative sea level (RSL) record for the period 8800 to 7800 cal yr BP developed from estuarine and salt-marsh deposits in SW Scotland. We find that RSL rose abruptly in three steps by 0.35 m, 0.7 m and 0.4 m (mean) at 8760-8640, 8595-8465, 8323-8218 cal yr BP respectively. The timing of these RSL steps correlate closely with short-lived events expressed in North Atlantic proxy climate and oceanographic records, providing evidence of at least three distinct episodes of enhanced meltwater discharge from the decaying LIS prior to the 8.2 event. Our observations can be used to test the fidelity of both climate and ice-sheet models in simulating abrupt change during the early Holocene.

  13. Source to sink element geochemistry and clay mineralogy in Lake Towuti, Indonesia: understanding climate-induced controls on sediment composition during the past 60 kyr BP

    NASA Astrophysics Data System (ADS)

    Morlock, Marina; Vogel, Hendrik; Nigg, Valentin; Hasberg, Ascelina; Melles, Martin; Russell, James M.; Bijaksana, Satria

    2016-04-01

    Lake Towuti is a large (560 km2 surface area; 198 m max. water depth) ultraoligotrophic lake hosted in the East Sulawesi ophiolite, characterised by high iron and very low sulphur contents. The lake is surrounded by several 10s of metres thick deeply weathered laterite soils and closed-canopy rainforest. In May-July 2015, we recovered more than 1000 m of sediment core capturing the entire sediment infill to bedrock in the course of the ICDP Towuti Drilling Project. In the tropics very little is known about the influence of climatic changes on weathering and erosion on glacial-interglacial time-scales. It is expected that varying hydroclimatic conditions will lead to changes in the weathering and erosion rates and greatly influence terrestrial elemental cycling. The direction of change and more quantitative estimates of the rates of changes are, however, unknown. In order to characterise modern erosional processes and element cycling in the lake and its catchment, we collected catchment-characteristic bedrock samples and profiles of their overlying laterites, riverine sediments, and 85 samples of surface sediments from the lake. All samples were analysed for their geochemical and clay-mineralogical (<2 μm) composition in order to define the composition of erodible substrates, trace source-to-sink changes in sediment composition, and assess the spatial variability in Lake Towuti. The relationships found in the modern system were then applied to two sediment cores, dating back 30,000 and 60,000 years BP, respectively. The laterite soils in the catchment show a characteristic zonation with high concentrations of Al, Ti, Fe, and Cr in the uppermost horizon, while Mg is enriched in the saprolite zone directly above bedrock. Weathering intensity increases from bedrock (least weathered) across river bedload of the 15 inlets to the sediments in the deepest basin of the lake (most weathered). The largest inlet to Lake Towuti, the Mahalona River, supplies sediments with low

  14. Late Holocene subalpine lake sediments record a multi-proxy shift to increased aridity at 3.65 kyr BP, following a millennial-scale neopluvial interval in the Lake Tahoe watershed and western Great Basin, USA

    NASA Astrophysics Data System (ADS)

    Noble, Paula; Zimmerman, Susan; Ball, Ian; Adams, Kenneth; Maloney, Jillian; Smith, Shane

    2016-04-01

    A mid Holocene dry period has been reported from lake records in the Great Basin and Sierra Nevada, yet the spatial and temporal extent of this interval is not well understood. We present evidence for a millennial-scale interval of high winter precipitation (neopluvial) at the end of the mid Holocene in the Lake Tahoe-Pyramid Lake watershed in the northern Sierra Nevada that reached its peak ˜3.7 kcal yr BP. A transect of 4 cores recovered from Fallen Leaf Lake in the Tahoe Basin were dated using AMS14C on plant macrofossils, and analyzed using scanning XRF, C and N elemental and stable isotope measurements, and diatoms as paleoclimate proxies. Fallen Leaf Lake is a deep glacially-derived lake situated in the Glen Alpine Valley at an elevation of 1942m, ˜45 m above the level of Lake Tahoe. In Fallen Leaf Lake, the end of the neopluvial is dated at 3.65 ± 0.09 kcal yr BP, and is the largest post-glacial signal in the cores. The neopluvial interval is interpreted to be a period of increased snowpack in the upper watershed, supported by depleted g δ13Corg (-27.5) values, negative baseline shifts in TOC and TN, lower C:N, and high abundances of Aulacoseira subarctica, a winter-early spring diatom. Collectively, these proxies indicate cooler temperatures, enhanced mixing, and/or shortened summer stratification resulting in increased algal productivity relative to terrestrial inputs. The neopluvial interval ends abruptly at 3.65 ka, with a change from mottled darker opaline clay to a homogeneous olive clay with decreased A. subarctica and opal, and followed by a 50% reduction in accumulation rates. After this transition δ13Corg becomes enriched by 2‰ and TOC, TN, and C:N all show the start of positive trends that continue through the Holocene. Pyramid Lake is an endorheic basin situated at the terminal end of the watershed, and inflow arrives from the Lake Tahoe basin via the Truckee River. At Pyramid Lake, existing ages on paleo-shorelines indicate a significant

  15. Century-scale climate-driven vegetation and environmental dynamics in southern Siberia during the last 47 kyr

    NASA Astrophysics Data System (ADS)

    Tarasov, Pavel; Bezrukova, Elena; Solovieva, Nadia; Riedel, Frank

    2010-05-01

    Radiocarbon-dated pollen and diatom records from Lake Kotokel in southern Siberia are used to reconstruct the environmental history of the area since ~47 kyr BP. Pollen data and reconstructed biome scores suggest predominance of a tundra-steppe vegetation and variable woody cover (5-20%) between ~47-30 kyr BP, indicating generally a harsh and unstable climate during this interval, conventionally regarded as the MIS3 interstadial. The short-term climate amelioration episodes in the glacial part of the records are marked by the peaks in taiga and corresponding minima in steppe biome scores and appear synchronously with the hemispheric temperature and precipitation changes recorded in the Greenland ice cores and Chinese stalagmites. The interval ~30-24 kyr BP was probably the driest and coldest of the whole record, as indicated by highest scores for steppe biome, woody coverage <5%, absence of diatoms and reduced size of the lake. A slight amelioration of the regional climate ~24-22 kyr BP was followed by a shorter than the previous and less pronounced deterioration phase. After 14.7 kyr BP the climate became warmer and wetter than ever during ~47-14.7 kyr BP, resulting in the deepening of the lake and increase in the woody coverage to 20-30% ~14.5-14 kyr and ~13.3-12.8 kyr BP. These two intervals correspond to the Meiendorf and Allerød interstadials, which until now were interpreted as part of the undifferentiated Bølling/Allerød interstadial complex in the Lake Baikal region. The increase in tundra biome scores and pronounced change in the diatom composition allow (for the first time) the unambiguous identification of the Younger Dryas (YD) in the region ~12.7-11.65 kyr BP, suggesting the synchronous onset of the YD and the Holocene interglacial across Eurasia. The maximal spread of the taiga communities in the region is associated with a warmer and wetter climate than the present prior to ~7 kyr BP. This was followed by a wide spread of Scots pine, indicating

  16. APGEN Version 5.0

    NASA Technical Reports Server (NTRS)

    Maldague, Pierre; Page, Dennis; Chase, Adam

    2005-01-01

    Activity Plan Generator (APGEN), now at version 5.0, is a computer program that assists in generating an integrated plan of activities for a spacecraft mission that does not oversubscribe spacecraft and ground resources. APGEN generates an interactive display, through which the user can easily create or modify the plan. The display summarizes the plan by means of a time line, whereon each activity is represented by a bar stretched between its beginning and ending times. Activities can be added, deleted, and modified via simple mouse and keyboard actions. The use of resources can be viewed on resource graphs. Resource and activity constraints can be checked. Types of activities, resources, and constraints are defined by simple text files, which the user can modify. In one of two modes of operation, APGEN acts as a planning expert assistant, displaying the plan and identifying problems in the plan. The user is in charge of creating and modifying the plan. In the other mode, APGEN automatically creates a plan that does not oversubscribe resources. The user can then manually modify the plan. APGEN is designed to interact with other software that generates sequences of timed commands for implementing details of planned activities.

  17. Paleomagnetic secular variation at Vulcano (Aeolian Islands) during the last 135 kyr

    NASA Astrophysics Data System (ADS)

    Lanza, Roberto; Zanella, Elena

    2003-08-01

    Paleosecular variation (PSV) of the Earth’s magnetic field during the last 135 kyr has been investigated in lavas, scoriae and pyroclastic rocks of Vulcano (Aeolian Islands). About 1000 samples have been collected at 77 sites from 25 distinct volcanic units, whose age is either known from published isotopical data or constrained on the grounds of statigraphical relationships. Magnetic mineralogy investigation shows that Ti-magnetite is the main ferromagnetic mineral. At most sites, secondary magnetization components are either absent or easily removed by stepwise thermal or alternating field demagnetization. The mean site direction of the characteristic remanent magnetization is usually well-defined, since the semi-angle of confidence is greater than 5° at only four sites. The mean paleomagnetic direction over the last 135 kyr (D=9.4°, I=53.2°, α95=3.5°) differs from the geocentric axial dipole (GAD) at Vulcano (D=0°, I=57.8°) and might be interpreted as the effect of a long-term, non-axial-dipolar component. The PSV record from Vulcano agrees well with those from the lacustrine sediments of Lago Grande di Monticchio (100 kyr BP) and Lago di Mezzano (30 kyr BP), located in the Italian peninsula [Brandt et al., Quat. Sci. Rev. 18 (1999) 961-976]. The inclination anomaly ΔI found at Vulcano corresponds to about half of the shallowing observed in the sediments of the two lakes and the declination anomaly ΔD may be used to tie the declination values, derived from azimuthally unoriented cores, to the geographical reference system. In order to find the optimum site to be used as reference for PSV studies in Italy, the angular values of the Earth’s magnetic field measured at the 113 repeat stations of the Italian Geomagnetic Network [Coticchia et al., Boll. Geod. Sci. Aff. 40 (2001) 277-291] have been analyzed with the relocation via pole method [Noel and Batt, Geophys. J. Int. 102 (1990) 753-756]. The Viterbo station (lat. 42°27‧N, long. 12°02

  18. Terrestrial biosphere changes over the last 120 kyr

    NASA Astrophysics Data System (ADS)

    Hoogakker, B. A. A.; Smith, R. S.; Singarayer, J. S.; Marchant, R.; Prentice, I. C.; Allen, J. R. M.; Anderson, R. S.; Bhagwat, S. A.; Behling, H.; Borisova, O.; Bush, M.; Correa-Metrio, A.; de Vernal, A.; Finch, J. M.; Fréchette, B.; Lozano-Garcia, S.; Gosling, W. D.; Granoszewski, W.; Grimm, E. C.; Grüger, E.; Hanselman, J.; Harrison, S. P.; Hill, T. R.; Huntley, B.; Jiménez-Moreno, G.; Kershaw, P.; Ledru, M.-P.; Magri, D.; McKenzie, M.; Müller, U.; Nakagawa, T.; Novenko, E.; Penny, D.; Sadori, L.; Scott, L.; Stevenson, J.; Valdes, P. J.; Vandergoes, M.; Velichko, A.; Whitlock, C.; Tzedakis, C.

    2016-01-01

    A new global synthesis and biomization of long (> 40 kyr) pollen-data records is presented and used with simulations from the HadCM3 and FAMOUS climate models and the BIOME4 vegetation model to analyse the dynamics of the global terrestrial biosphere and carbon storage over the last glacial-interglacial cycle. Simulated biome distributions using BIOME4 driven by HadCM3 and FAMOUS at the global scale over time generally agree well with those inferred from pollen data. Global average areas of grassland and dry shrubland, desert, and tundra biomes show large-scale increases during the Last Glacial Maximum, between ca. 64 and 74 ka BP and cool substages of Marine Isotope Stage 5, at the expense of the tropical forest, warm-temperate forest, and temperate forest biomes. These changes are reflected in BIOME4 simulations of global net primary productivity, showing good agreement between the two models. Such changes are likely to affect terrestrial carbon storage, which in turn influences the stable carbon isotopic composition of seawater as terrestrial carbon is depleted in 13C.

  19. Observation of 23 supernovae that exploded <300 pc from Earth during the past 300 kyr

    SciTech Connect

    Firestone, R. B.

    2014-07-01

    Four supernovae (SNe), exploding ≤300 pc from Earth, were recorded 44, 37, 32, and 22 kyr ago in the radiocarbon ({sup 14}C) record during the past 50 kyr. Each SN left a nearly identical signature in the record, beginning with an initial sudden increase in atmospheric radiocarbon, when the SN exploded, followed by a hiatus of 1500 yr, and concluding with a sustained 2000 yr increase in global radiocarbon due to γ-rays produced by diffusive shock in the SN remnant (SNR). For the past 18 kyr excess radiocarbon has decayed with the {sup 14}C half-life. SN22kyrBP, is identified as the Vela SN that exploded 250 ± 30 pc from Earth. These SN are confirmed in the {sup 10}Be, {sup 26}Al, {sup 36}Cl, and NO{sub 3}{sup −} geologic records. The rate of near-Earth SNe is consistent with the observed rate of historical SNe giving a galactic rate of 14 ± 3 kyr{sup –1} assuming the Chandra Galactic Catalog SNR distribution. The Earth has been used as a calorimeter to determine that ≈2 × 10{sup 49} erg were released as γ-rays at the time of each SN explosion and ≈10{sup 50} erg in γ-rays following each SN. The background rate of {sup 14}C production by cosmic rays has been determined as 1.61 atoms cm{sup –2} s{sup –1}. Approximately 1/3 of the cosmic ray energy produced by diffusive shock in the SNR was observed to be emitted as high-energy γ-rays. Analysis of the {sup 10}Be/{sup 9}Be ratio in marine sediment identified 19 additional near-Earth SNe that exploded 50-300 kyr ago. Comparison of the radiocarbon record with global temperature variations indicated that each SN explosion is correlated with a concurrent global warming of ≈3°C-4°C.

  20. AutoGen Version 5.0

    NASA Technical Reports Server (NTRS)

    Gladden, Roy E.; Khanampornpan, Teerapat; Fisher, Forest W.

    2010-01-01

    Version 5.0 of the AutoGen software has been released. Previous versions, variously denoted Autogen and autogen, were reported in two articles: Automated Sequence Generation Process and Software (NPO-30746), Software Tech Briefs (Special Supplement to NASA Tech Briefs), September 2007, page 30, and Autogen Version 2.0 (NPO- 41501), NASA Tech Briefs, Vol. 31, No. 10 (October 2007), page 58. To recapitulate: AutoGen (now signifying automatic sequence generation ) automates the generation of sequences of commands in a standard format for uplink to spacecraft. AutoGen requires fewer workers than are needed for older manual sequence-generation processes, and greatly reduces sequence-generation times. The sequences are embodied in spacecraft activity sequence files (SASFs). AutoGen automates generation of SASFs by use of another previously reported program called APGEN. AutoGen encodes knowledge of different mission phases and of how the resultant commands must differ among the phases. AutoGen also provides means for customizing sequences through use of configuration files. The approach followed in developing AutoGen has involved encoding the behaviors of a system into a model and encoding algorithms for context-sensitive customizations of the modeled behaviors. This version of AutoGen addressed the MRO (Mars Reconnaissance Orbiter) primary science phase (PSP) mission phase. On previous Mars missions this phase has more commonly been referred to as mapping phase. This version addressed the unique aspects of sequencing orbital operations and specifically the mission specific adaptation of orbital operations for MRO. This version also includes capabilities for MRO s role in Mars relay support for UHF relay communications with the MER rovers and the Phoenix lander.

  1. The burial of organic carbon over the last 10 kyr by the Waipaoa River, New Zealand sedimentary system

    NASA Astrophysics Data System (ADS)

    Blair, N. E.; Childress, L. B.; Fournillier, K. M.; Leithold, E. L.

    2013-12-01

    Small mountainous rivers (SMRs), most of which are located along active margins, play a unique role in marine and global carbon cycles. SMRs drain only ~20% of land, but deliver approximately 40% of the fluvial sediment to the global ocean. Unlike large passive margin systems in which riverine organic carbon (OC) is efficiently incinerated on continental shelves, SMR-dominated shelves are highly effective in the burial and preservation of OC. This is the result of the rapid, episodic delivery of OC derived from terrestrial vegetation, aged soil organic matter, and sedimentary rock OC. Most of our understanding concerning the carbon cycling dynamics of SMR systems is derived from modern, heavily anthropogenically impacted environments however. The nature and fluxes of OC prior to land use change is poorly documented. Erosion and depositional patterns associated with SMRs are affected by several large-scale forcing mechanisms, primarily climate and tectonics. To investigate the effect of natural and anthropogenic forcing on the geochemical record of a SMR we use the Waipaoa River, New Zealand. The Waipaoa River is a system of interest due to its large current sediment yield (6800 tons km-2 yr-1) and extensive characterization. Continental shelf cores collected offshore of the Waipaoa by the MATACORE group aboard the R/V Marion Dufresne extend to 10 kyr BP, and records climatic transitions with tectonic overprints in the region. The OC burial flux ranged from ~15-20 kg C m-2 kyr-1 at the location of one shelf core (MD 3007) approximately 3.5-10 kyr before present. This corresponds to a period of relatively rapid shoreline progradation. OC accumulation decreased to ~4-6 kg C m-2 kyr-1 after 3.5 kyr BP. Anthropogenic deforestation has caused OC burial fluxes to rebound to beyond the 3.5-10 kyr levels. Organic geochemical proxies, including δ13C, δ15N, and lignin phenols, indicate a depositional site that is dominated by riverine input. The proxies do not correlate

  2. 50-kyr vegetation history in the western Verkhoyansk Mountains region (NE Asia) reconstructed from fossil pollen data

    NASA Astrophysics Data System (ADS)

    Müller, Stefanie; Tarasov, Pavel E.; Andreev, Andrei A.; Tütken, Thomas; Gartz, Steffi; Diekmann, Bernhard

    2010-05-01

    A detailed radiocarbon-dated pollen record from Lake Billyakh (65°17'N, 126°47'E; 340 m a.s.l.) situated in the western part of the Verkhoyansk Mountains, about 140 km south of the Arctic Circle is presented. A set of 53 surface pollen samples representing tundra, cold-deciduous forest and taiga was collected in northern and central Yakutia communities to verify the accuracy of the quantitative biome reconstruction method and to obtain a more precise attribution of the identified pollen taxa to the main regional biomes. The adjusted method is then applied to the pollen record from Lake Billyakh to gain an objective reconstruction of vegetation and environments since about 50.7 kyr BP. The results of the pollen analysis and pollen-based biome reconstruction suggest that herbaceous tundra and steppe communities dominated the area from 50.7 to 13.5 kyr BP. The lowest pollen percentages of woody taxa and the highest values of Artemisia pollen attest that the 31-15 kyr BP period as the driest and coldest interval of the entire record. A relative high content of taxa representing shrub tundra communities and the presence of larch pollen recorded prior to 31 kyr and after 13.5 kyr BP likely indicate interstadial climate amelioration associated with the middle and latest parts of the last glacial. An increase in pollen percentages of herbaceous taxa around 12 kyr BP suggests broader distribution of drier communities in response to the colder and drier than present climate of the Younger Dryas. The onset of the Holocene is marked by the highest values of shrub taxa, mainly Betula sect. Nanae/Fruticosae. Pollen percentages of arboreal taxa increase gradually and reach maximum values after 7 kyr BP. The latter maximum mainly reflects the spread of Pinus sylvestris in central Yakutia as a response to the mid-Holocene climatic optimum. The quasi-continuous presence of larch, shrubby birch and alder pollen throughout the whole record is the most striking feature of the pollen

  3. Droughts in the East Asian summer monsoon margin during the last 6 kyrs: Link to the North Atlantic cooling events

    NASA Astrophysics Data System (ADS)

    Fan, Jiawei; Xiao, Jule; Wen, Ruilin; Zhang, Shengrui; Wang, Xu; Cui, Linlin; Li, He; Xue, Dingshuai; Yamagata, Hideki

    2016-11-01

    Teleconnections to the high latitudes, forcing by the tropical oceans and solar variability have all been suggested as dominant factors in the sub-millennial global climate changes, yet there is little consensus as to the relative importance of these factors for the East Asian summer monsoon (EASM) variability. This study presents the results of high-resolution analyses of Ca and Mg concentrations, Mg/Ca ratio, δ18O and δ13C values of endogenic calcites from a sediment core from Dali Lake in the EASM margin, in order to investigate the sub-millennial EASM variability and its possible driving forces during the last 6 kyrs. Increases in these chemical proxy data were interpreted as drought events in the region due to the intensive evaporation losses overwhelming the water input to the lake. The chemical proxy data in this study combined with multi-proxy indicators including grain size component and total organic carbon concentrations from the same sediment core imply that declines in the EASM intensity may have played a dominant role in triggering the drought events during the last 6 kyrs. The results indicate that the EASM intensity significantly declined at the intervals of 5.8-4.75, 3.2-2.8, 1.65-1.15 and 0.65-0.2 kyrs BP. Large declines in the EASM intensity during the last 6 kyrs correspond in time to occurrences of ice-rafted debris in the North Atlantic, indicating that millennial-to-centennial scale changes in the EASM intensity were mainly controlled by climatic processes occurring in the northern high latitudes. These data imply that persistent global warming may be favorable for the strengthening of the EASM circulation and for the transportation of more rainfall to the semi-arid regions of northern China on sub-millennial scales.

  4. Integrated stratigraphic reconstruction for the last 80 kyr in a deep sector of the Sardinia Channel (Western Mediterranean)

    NASA Astrophysics Data System (ADS)

    Budillon, F.; Lirer, F.; Iorio, M.; Macrì, P.; Sagnotti, L.; Vallefuoco, M.; Ferraro, L.; Garziglia, S.; Innangi, S.; Sahabi, M.; Tonielli, R.

    2009-05-01

    A quantitative analysis of planktonic foraminifera, coupled with petrophysical and paleomagnetic measurements and 14C-AMS calibrations, was carried out on a deep core recovered in the Sardinia Channel (Western Mediterranean Sea), during the CIESM Sub2 survey, providing an integrated stratigraphic time-framework over the last 80 kyr. Significant changes in the quantitative distribution of planktonic foraminifera allowed the identification of several eco-bioevents useful to accurately mark the boundaries of the eco-biozones widely recognized in the Western Mediterranean records and used for large-scale correlations. Namely, 10 eco-biozones were identified based on the relative abundance of selected climate-sensitive planktonic foraminiferal species. Sixteen codified eco-bioevents were correlated with Alboran Sea planktonic foraminiferal data and several climatic global events (Sapropel S1, Younger Dryas, Greenland Isotope Interstadial 1, Greenland Isotope Stadial 2, Heinrich event H1-H6) were recognized. The eco-bioevents together with the 14C-AMS calibrations allowed us to define an accurate age model, spanning between 2 and 83 kyr. The reliability of the age model was confirmed by comparing the colour reflectance (550 nm%) data of the studied record with the astronomically tuned record from the Ionian Sea (ODP-Site 964). A mean sedimentation rate of about 7 cm/kyr included three turbidite event beds that were chronologically constrained within the relative low stand and regressive sea-level phases of MIS 4 and 3. The deep-sea sedimentary record includes a distinct tephra occurring at the base of the core that dates 78 ka cal. BP. The paleomagnetic data provide a well-defined record of the characteristic remanent magnetization that may be used to reconstruct the geomagnetic paleosecular variation for the Mediterranean back to 83 kyr.

  5. Late Quaternary vegetation and environments in the Verkhoyansk Mountains region (NE Asia) reconstructed from a 50-kyr fossil pollen record from Lake Billyakh

    NASA Astrophysics Data System (ADS)

    Müller, Stefanie; Tarasov, Pavel E.; Andreev, Andrei A.; Tütken, Thomas; Gartz, Steffi; Diekmann, Bernhard

    2010-08-01

    Here we present a detailed radiocarbon-dated 936 cm long pollen record from Lake Billyakh (65°17'N, 126°47'E; 340 m a.s.l.) situated in the western part of the Verkhoyansk Mountains, about 140 km south of the Arctic Circle. A set of 53 surface pollen samples representing tundra, cold deciduous forest and taiga was collected in northern and central Yakutia communities to verify the accuracy of the quantitative biome reconstruction method and to obtain a more precise attribution of the identified pollen taxa to the main regional biomes. The adjusted method is then applied to the pollen record from Lake Billyakh to gain a reconstruction of vegetation and environments since about 50.7 kyr BP. The results of the pollen analysis and pollen-based biome reconstruction suggest that herbaceous tundra and steppe communities dominated the area from 50.7 to 13.5 kyr BP. Relatively low pollen concentrations and high percentages of herbaceous pollen taxa (mainly Cyperaceae, Poaceae and Artemisia) likely indicate a reduced vegetation cover and/or lower pollen production. On the other hand, extremely low percentages of drought-tolerant taxa, such as Chenopodiaceae and Ephedra, and the constant presence of various mesophyllous herbaceous ( Thalictrum, Rosaceae, Asteraceae) and shrubby taxa ( Betula sect. Nanae/Fruticosae, Duschekia fruticosa, Salix) in the pollen assemblages prevent an interpretation of the last glacial environments around Lake Billyakh as extremely arid. The lowest pollen percentages of woody taxa and the highest values of Artemisia pollen attest that the 31-15 kyr BP period as the driest and coldest interval of the entire record. A relative high content of taxa representing shrub tundra communities and the presence of larch pollen recorded prior to 31 kyr and after 13.5 kyr BP likely indicate interstadial climate amelioration associated with the middle and latest parts of the last glacial. An increase in pollen percentages of herbaceous taxa around 12 kyr BP

  6. Dinocyst assemblage constraints on oceanographic and atmospheric processes in the eastern equatorial Atlantic over the last 44 kyr

    NASA Astrophysics Data System (ADS)

    Hardy, William; Penaud, Aurélie; Marret, Fabienne; Bayon, Germain; Marsset, Tania; Droz, Laurence

    2016-08-01

    A new 44 kyr long record of dinoflagellate (phytoplanktonic organisms) cysts (dinocysts) is presented from a marine sediment core collected on the Congolese margin with the aim of reconstructing past hydrological changes in the equatorial eastern Atlantic Ocean since Marine Isotopic Stage (MIS) 3. Our high-resolution dinocyst record indicates that significant temperature and moisture variations occurred across the glacial period, the last deglaciation and the Holocene. The use of specific dinocyst taxa, indicative of fluvial, upwelling and Benguela Current past environments for instance, provides insights into the main forcing mechanisms controlling palaeohydrological changes on orbital timescales. In particular, we are able, for the last 44 kyr, to correlate fluvial-sensitive taxa to monsoonal mechanisms related to precession minima-obliquity maxima combinations. While upwelling mechanisms appear as the main drivers for dinoflagellate productivity during MIS 2, dissolved nutrient-enriched Congo River inputs to the ocean also played a significant role in promoting dinoflagellate productivity between approximately 15.5 and 5 ka BP. Finally, this high-resolution dinocyst study permits us to precisely investigate the suborbital timing of the last glacial-interglacial termination, including an atypical warm and wet oceanic LGM signature, northern high-latitude abrupt climate change impacts in the equatorial eastern Atlantic, as well as a two-step decrease in moisture conditions during the Holocene at around 7-6 and 4-3.5 ka BP.

  7. 38 kyr record of Asian dust deposition in Hawaii: its links to interglacial/glacial changes

    NASA Astrophysics Data System (ADS)

    Kim, S. H.; Hotchkiss, S.; Vitousek, P.; Chadwick, O.; Mason, J. A.

    2015-12-01

    Asian desert dust is the major inorganic fraction of late Cenozoic sediments in the North Pacific. Dust modelling, satellite observations and stable isotope data have contributed to understanding of the dust provenance, teleconnection and process mechanisms. Most paleo-aeolian data have suggested positive links between Asian dust input variability and glacial-interglacial cycles in the North Pacific. However, existing Pacific paleodust studies mostly depend on low-resolution marine records at mid- and high-latitudes. In this study, we reconstruct 38 kyr terrestrial records of Asian dust deposition from Hawaiian montane peat bogs. We also focus on interpreting temporal correlations of the Asian dust flux history with its local hydrological variability over late Quaternary interglacial/glacial changes because of the significant positive correlation between Asian dust mass in Hawaiian surface soils and annual precipitations (Figure A1 & A2). For a proxy for Asian dust in Hawaii, we use quartz, a continental igneous rock-driven mineral type absent in Hawaiian basaltic rocks. Using an X-ray diffraction method, we quantify quartz content and calculate quartz deposition rates. We also reconstruct Hawaiian paleoprecipitation history by using pollen assemblage and peat humification degree analyses. Our results present two significant quartz deposition peaks during the Last Glacial Maximum (0.134 g/cm3) and between 2.6 and 0.4 kyr BP (0.044 g/cm3). Our moisture varaition results show that Hawaii was drier during the LGM than the Holocene. Therefore, this study suggests that Asian dust input in Hawaii has negative temporal correlations with wet deposition-controlling climates, but positive correlations with the drier glacial period in the late Quaternary.

  8. Scenario Of The 4 kyr Extraterrestrial Impact : Crater Location, Ejecta-Dispersion and Consequences.

    NASA Astrophysics Data System (ADS)

    Courty, M.; Abbott, D. H.; Cortese, G.; Crisci, A.; Crosta, X.; de Wever, P.; Fedoroff, M.; Greenwood, P.; Grice, K.; Mermoux, M.; Scharer, U.; Smith, D. C.; Thiemens, M. H.

    2006-12-01

    The 4 kyr BP impact event has been identified from deep-sea, soil and archaeological records as the worldwide pulverisation of a volatile-rich debris jet(1). High resolution sequences show two stages of ejecta fallout linked to the impact-triggered doublet gaseous regime(2): scattered solid debris at the ground surface and spray of the vaporized hot fireball with thermal blast and local ignition. Ejecta debris consist of flow- textured impact glass, impact breccia and incompletely melted marine clasts: volcano-clastic sandy mudstone, calcareous mud, granite-gneiss, schists, volcanic breccia, kerogen and algal mud. Marine microfossils, organo-mineral markers, and the debris-fallout spatial pattern indicate two potential impact craters: an Antarctic source with an admixture of volcanic glass and ice rafted debris, from the vicinity of Heard Island and the Kerguelen plateau; a low latitude, shallow water one with hydrocarbons possibly from the Gulf of Mexico. Fine mixing of target materials from far distant source craters emphasizes a unique impact-ejecta. This matches the theoretical view of a debris jet channelled along the corridor cut through the atmosphere by the incoming projectile, raised upward, and dispersed widely(3). The isotopic anomaly of the sulphur phase in the kerogen volatile-component, indicating mass independent fractionation due to photolytic transformation, suggests launching at great heights, beyond the O2-O3 UV shield, responsible for climate disturbances. The incomplete melting of target rocks and global dispersion of impact breccia out of the craters would result from splash of small-sized projectile at rather great water depth and a low angle impact (10-15 degrees) into porous, highly compressible marine sediments. The spatially variable distribution of the organo-mineral and melt components, and the wide range of phase transformation reflect nonequilibrium shock-melting and micro-scale thermal processes in the heterogeneous vapor plume

  9. Human Exploration of Mars Design Reference Architecture 5.0

    NASA Technical Reports Server (NTRS)

    Drake, Bret G.

    2010-01-01

    This paper provides a summary of the Mars Design Reference Architecture 5.0 (DRA 5.0), which is the latest in a series of NASA Mars reference missions. It provides a vision of one potential approach to human Mars exploration. The reference architecture provides a common framework for future planning of systems concepts, technology development, and operational testing as well as Mars robotic missions, research that is conducted on the International Space Station, and future lunar exploration missions. This summary the Mars DRA 5.0 provides an overview of the overall mission approach, surface strategy and exploration goals, as well as the key systems and challenges for the first three human missions to Mars.

  10. Human Exploration of Mars Design Reference Architecture 5.0

    NASA Technical Reports Server (NTRS)

    Drake, Bret G.; Hoffman, Stephen J.; Beaty, David W.

    2009-01-01

    This paper provides a summary of the 2007 Mars Design Reference Architecture 5.0 (DRA 5.0), which is the latest in a series of NASA Mars reference missions. It provides a vision of one potential approach to human Mars exploration including how Constellation systems can be used. The reference architecture provides a common framework for future planning of systems concepts, technology development, and operational testing as well as Mars robotic missions, research that is conducted on the International Space Station, and future lunar exploration missions. This summary the Mars DRA 5.0 provides an overview of the overall mission approach, surface strategy and exploration goals, as well as the key systems and challenges for the first three human missions to Mars.

  11. Plio-Pleistocene time evolution of the 100-kyr cycle in marine paleoclimate records

    NASA Technical Reports Server (NTRS)

    Park, Jeffrey; Maasch, Kirk A.

    1993-01-01

    A new time-series analysis technique (called envelope inversion), which is based on multiple taper spectral analysis, is used to address the question of an abrupt versus a gradual onset of the 100-kyr ice-age periodicity in the middle Pleistocene. Three long (greater than 2.6 m.y.) time series from Deep Sea Drilling Project site 607 (midlatitude Atlantic) and Ocean Drilling Program site 677 (equatorial Pacific) were analyzed using delta(O-18) records. Results do not yield compelling evidence for an abrupt change in the 100-kyr delta(O-18) signal. Rather, the results suggest that the 100-kyr delta(O-18) cycle is phase-locked with the 124-kyr eccentricity cycle some 300-400 kyr prior to its late Pleistocene growth in amplitude and phase lock with the 95-kyr eccentricity cycle.

  12. 2007 Version 5.0 Technical Support Document

    EPA Pesticide Factsheets

    Preparation of Emissions Inventories for the Version 5.0, 2007 Emissions Modeling Platform describes how emissions based on the 2008 NEI, version 2 and were processed to represent the year 2007 in support of air quality modeling of the PM NAAQS.

  13. Multi-proxy sedimentary record from Lake Ghirla (N-Italy) reveals hydro-climatic variations and periods of anthropogenic activities during the past 13 kyrs

    NASA Astrophysics Data System (ADS)

    Wirth, Stefanie B.; Gilli, Adrian; Sessions, Alex L.

    2016-04-01

    Lake Ghirla is a small lake that lies in the southern foothills of the Central Alps near the Swiss-Italian border. Climatically, the region is influenced by North Atlantic and Mediterranean weather systems and is frequently affected by severe storm tracks causing heavy precipitation. The catchment with Permian granites and gneisses contains Pb in amounts significant for mining as well as less important concentrations of Cu, As and U. This sensitive setting makes Lake Ghirla a promising site to reconstruct hydro-climatic variations and to track human activity by means of elevated heavy metal concentrations in the lake sediments. The recovered sediment core comprises the entire Younger Dryas-Holocene time period and was analyzed for (i) sedimentological changes to identify flood deposits, for (ii) the hydrogen isotopic composition of terrestrial plant waxes (plant-wax D/H) to constrain hydro-climatic changes, and for (iii) variations of the elemental composition (XRF core scanning, ICP-MS) to understand anthropogenic impacts. During the past 13 kyrs, we observe a high variability of floods with peak periods appearing at ~11, 10.6-8.2, 6-4.9, 2.8-2.7, 2.6-2.4, 1.2-1 and 0.4-0.1 (LIA) cal kyr BP. From a hydro-climatic perspective, the most remarkable result from the plant-wax D/H data is that the Younger Dryas is characterized by no significant change and that the 2.8-2.7 kyr BP and LIA intervals show an increase of plant-wax D/H values. Hence, during these three cool climatic periods temperature effects cannot be solely responsible for plant-wax D/H variation. The southward migration of the westerly storm tracks above the North Atlantic due to climate cooling must have led to a more southern and thus isotopically enriched moisture source for the southern Alps. This moisture-source change likely counter-balanced or even over-rode the temperature-driven isotope effect. Increased sedimentary Cu concentrations at 3.8-3.3 kyr BP are the first evidence for the presence of

  14. The Sima de los Huesos hominids date to beyond U/Th equilibrium (>350 kyr) and perhaps to 400-500 kyr: New radiometric dates

    USGS Publications Warehouse

    Bischoff, J.L.; Shamp, D.D.; Aramburu, Arantza; Arsuaga, J.L.; Carbonell, E.; Bermudez de Castro, Jose Maria

    2003-01-01

    The Sima de los Huesos site of the Atapuerca complex near Burgos, Spain contains the skeletal remains of at least 28 individuals in a mud breccia underlying an accumulation of the Middle Pleistocene cave bear (U. deningeri). Earlier dating estimates of 200 to 320 kyr were based on U-series and ESR methods applied to bones, made inaccurate by unquantifiable uranium cycling. We report here on a new discovery within the Sima de los Huesos of human bones stratigraphically underlying an in situ speleothem. U-series analyses of the speleothem shows the lower part to be at isotopic U/Th equilibrium, translating to a firm lower limit of 350 kyr for the SH hominids. Finite dates on the upper part suggest a speleothem growth rate of c. 1 cm/32 kyr. This rate, along with paleontological constraints, place the likely age of the hominids in the interval of 400 to 600 kyr. ?? 2002 Elsevier Science Ltd. All rights reserved.

  15. Spectrum of 100-kyr glacial cycle: orbital inclination, not eccentricity.

    PubMed

    Muller, R A; MacDonald, G J

    1997-08-05

    Spectral analysis of climate data shows a strong narrow peak with period approximately 100 kyr, attributed by the Milankovitch theory to changes in the eccentricity of the earth's orbit. The narrowness of the peak does suggest an astronomical origin; however the shape of the peak is incompatible with both linear and nonlinear models that attribute the cycle to eccentricity or (equivalently) to the envelope of the precession. In contrast, the orbital inclination parameter gives a good match to both the spectrum and bispectrum of the climate data. Extraterrestrial accretion from meteoroids or interplanetary dust is proposed as a mechanism that could link inclination to climate, and experimental tests are described that could prove or disprove this hypothesis.

  16. Latitudinal Hydrologic Variability Along the East African Rift, Over the Past 200 Kyr

    NASA Astrophysics Data System (ADS)

    Scholz, C. A.

    2014-12-01

    Within the deep sediments of the large lakes of Africa's Great Rift Valley are continuous environmental records of remarkable antiquity and fidelity. Not only do stratigraphic sections from these basins extend back millions of years, many of the intervals represented contain high-resolution material of decadal resolution or better. East African lake basins remain sparsely sampled however, with only a few long and continuous records available. Our ability to image the lakes using seismic reflection methods greatly exceeds our opportunities for coring and drilling however; assessing stratal relationships observed in the geophysical data permits powerful inferences about past hydrologic changes. With intensive hydrocarbon exploration work underway in East Africa, industry well data can also help constrain and ground truth basin histories. Substantial spatio-temporal hydrologic variability is observed in East African basins over the past 200 kyr. Paleohydrological changes in the late Pleistocene and early Holocene are now well constrained in the northern hemisphere East African topics, with widespread aridity and in some cases lake desiccation observed during Heinrich Event 1. A climate recovery followed in the northern hemisphere East African tropics, with the early Holocene African Humid Period a time of positive water balance across most of the rift valley. The paleohydrology of southern hemisphere tropical East Africa is more equivocal, for instance with negligible draw-down of Lake Malawi at HE1. Whereas these late Pleistocene events represent substantial climate reorganizations, severe droughts during the middle-late Pleistocene (150-65 kyr BP) were far more intense, and produced much more severe drawdowns of Lakes Malawi and Tanganyika. Scientific drill cores, kullenberg cores, and extensive seismic reflection data sets from Lakes Malawi and Tanganyika provide indisputable evidence for lowstands of -500m and -600 m respectively. Climate changes that lowered the

  17. Quantitative woody cover reconstructions from eastern continental Asia of the last 22 kyr reveal strong regional peculiarities

    NASA Astrophysics Data System (ADS)

    Tian, Fang; Cao, Xianyong; Dallmeyer, Anne; Ni, Jian; Zhao, Yan; Wang, Yongbo; Herzschuh, Ulrike

    2016-04-01

    We present a calibration-set based on modern pollen and satellite-based Advanced Very High Resolution Radiometer (AVHRR) observations of woody cover (including needleleaved, broadleaved and total tree cover) in eastern continental Asia, which shows good performance under cross-validation with the modern analogue technique (all the coefficients of determination between observed and predicted values are greater than 0.65). The calibration-set is used to reconstruct woody cover from a taxonomically harmonized and temporally standardized fossil pollen dataset (including 274 cores) with 500-year resolution over the last 22 kyr. The spatial range of forest has not noticeably changed in eastern continental Asia during the last 22 kyr, although woody cover has, especially at the margin of the eastern Tibetan Plateau and in the forest-steppe transition area of north-central China. Vegetation was sparse during the LGM in the present forested regions, but woody cover increased markedly at the beginning of the Bølling/Allerød period (B/A; ca. 14.5 ka BP) and again at the beginning of the Holocene (ca. 11.5 ka BP), and is related to the enhanced strength of the East Asian Summer Monsoon. Forest flourished in the mid-Holocene (ca. 8 ka BP) possibly due to favourable climatic conditions. In contrast, cover was stable in southern China (high cover) and arid central Asia (very low cover) throughout the investigated period. Forest cover increased in the north-eastern part of China during the Holocene. Comparisons of these regional pollen-based results with simulated forest cover from runs of a global climate model (for 9, 6 and 0 ka BP (ECHAM5/JSBACH ∼1.125° spatial resolution)) reveal many similarities in temporal change. The Holocene woody cover history of eastern continental Asia is different from that of other regions, likely controlled by different climatic variables, i.e. moisture in eastern continental Asia; temperature in northern Eurasia and North America.

  18. Mars Design Reference Architecture 5.0 Study: Executive Summary

    NASA Technical Reports Server (NTRS)

    Drake, Bret G.

    2008-01-01

    The NASA Mars Design Reference Architecture 5.0 Study seeks to update its long term goals and objective for human exploration missions; flight and surface systems for human missions and supporting infrastructure; operational concept for human and robotic exploration of Mars; key challenges including risk and cost drivers; and, its development schedule options. It additionally seeks to assess strategic linkages between lunar and Mars strategies and develop and understanding of methods for reducing the cost/risk of human Mars missions through investment in research, technology development, and synergy with other exploration plans. Recommendations are made regarding conjunction class (long-stay) missions which are seen as providing the best balance of cost, risk, and performance. Additionally, this study reviews entry, descent, and landing challenges; in-space transportation systems; launch vehicle and Orion assessments; risk and risk mitigation; key driving requirements and challenges; and, lunar linkages.

  19. Nuclear waste glass product consistency test (PCT), Version 5. 0

    SciTech Connect

    Jantzen, C.M.; Bibler, N.E.; Beam, D.C.; Ramsey, W.G.; Waters, B.J.

    1992-06-01

    Liquid high-level nuclear waste will be immobilized at the Savannah River Site (SRS) by vitrification in borosilicate glass. The glass will be produced in the Defense Waste Processing Facility (DWPF), poured into stainless steel canisters, and eventually disposed of in a geologic repository. In order to comply with the Waste Acceptance Preliminary Specifications (WAPS), the durability of the glass needs to be measured during production to assure its long term stability and radionuclide release properties. A durability test, designated the Produce Consistency Test (PCT), was developed for DWPF glass in order to meet the WAPS requirements. The response of the PCT procedure was based on extensive testing with glasses of widely different compositions. The PCT was determined to be very reproducible, to yield reliable results rapidly, and to be easily performed in shielded cell facilities with radioactive samples. Version 5.0 of the PCT procedure is attached.

  20. AGN flickering on 10-100 kyr timescales

    NASA Astrophysics Data System (ADS)

    Sartori, Lia F.; Schawinski, Kevin; Kill, Bill; Maksym, Peter; Koss, Michael; Argo, Megan; Urry, Meg; Wong, Ivy; Lintott, Chris

    2016-08-01

    The study of AGN variability on timescales of 10^4-10^5 years is important in order to understand the BH - host galaxy interaction and coevolution. The discovery of "Hanny's Voorwerp" (HV), an extended emission line region associated with the nearby galaxy IC 2497, provided us with a laboratory to study AGN variability over such timescales. HV was illuminated by a strong quasar in IC 2497, but this quasar significantly shut down in the last 200 kyrs. Thanks to its recent shutdown we can now explore the host galaxy unimpeded by the presence of a quasar dominating the observations, while the Voorwerp preserves the echoes of its past activity. Recent studies on the optical properties of hard X-ray selected AGN suggest that AGN may flicker on and off hundreds or thousands times with each burst lasting ~10^5 yrs. Systems similar to IC 2497 and HV, the so-called Voorwerpjes, allow us to constrain the last stages of the AGN lifecycle. On the other hand, we recently suggested that the switch on phase may be observed in the so-called optically elusive AGN. In this talk I will review both observational evidence and results from simulation work which support this picture, and explain how optically elusive AGN and Voorwerpjes galaxies can help us to understand different phases of the AGN lifecycle. Moreover, I will discuss possible implications for AGN feedback, BH - host galaxy coevolution, and the analogy between AGN and X-ray binaries accretion physics.

  1. Dome collapse eruption in Tatun Volcanic Group near metropolitan Taipei, Taiwan at ~6 kyrs

    NASA Astrophysics Data System (ADS)

    Chen, C.; Lee, T.

    2010-12-01

    The Tatun Volcanic Group (TVG) is located in the north of metropolitan Taipei, Taiwan. Over 6 million inhabitants are living in Taipei City and suburban area. Another critical issue is an international airport and two nuclear power plants are lying at the foot of the TVG. If the TGV will be re-active, the serious hazard for human lives and economies in this area will definitely occur. Understanding the youngest eruption history of the TVG will be much important for prediction the future activity of eruption. The core was collected from the Dream Lake at the eastern slop of Cising Mt.. Total 21 samples from depth 190 cm to 231.5 cm have been tested. Comparison of chemical compositions of glass and minerals in the volcanic clasts with those of lava around TVG, they clearly showed that the volcanic clasts can be correlated with the eruption of the closest Cising Mt. According to the radiocarbon (C-14) age of core sample at the depth 225 cm, the age was extrapolated around 6150 yrs ca. C-14 B.P.. Moreover, the respiratory cristobalite in the volcanic clasts were firstly identified by the identical morphology, chemical composition and Laser Raman Spectrometry (LRS). The crystalline silica was produced by vapor-phase crystallization and devitrification in the andesite lava dome and volcanic ash generated by pyroclastic flows formed by lava dome collapse in Soufriere Hills volcano, Montserrat (Baxter et al.,1999). These new evidence demonstrated that there would probably have the lava dome collapse eruptions in the TVG in the last 6 kyrs. The result in this paper also sustained that the landslide caused by the weak phreatic eruption within the last 6000 yrs in the TVG (Belousov et al., 2010). It must further be noted that an efficient program of the volcanic hazard reduction should be practiced for the metropolitan Taipei and suburban area.

  2. Multiproxy approach revealing climate and cultural changes during the last 26kyrs in south-central Chile

    NASA Astrophysics Data System (ADS)

    Abarzua, Ana M.; Jarpa, Leonora; Martel, Alejandra; Vega, Rodrigo; Pino, Mario

    2010-05-01

    Multiproxy approach from Purén Lumaco Valley (38°S) describes the paleonvironmental history during the Last Maximum Glacial (LGM) in south-central Chile. Three sediment cores and severals AMS 14C dates were used to perform a complete pollen, diatoms, chironomids, and sedimentological records demonstrating the existence of a large and non profundal paleolake, between 25 and 20kyr BP. Some of these evidence are laminated silty-clay sediments (lacustrine rhythmites), associated with the presence of siderite mineral (FeCO3), besides biological proxies like Fragilaria construens and Stauroforma inermes (planctonic diatoms), and Dicrotendipes sp. and Tanytarsini tribe (littoral chironomids). The pollen ensemble reveals the first glacial refuge of Araucaria araucana forests in the low lands during the LGM. The lake was drained abruptly into a swamp/bog at 12kyr BP and colonized by Myrtaceae wet forest. This evidence suggest the dry/warm climate period of early Holocene in south-central Chile. Later, the sediments indicate variable lacustrine levels, and increase of charcoal particles, associated to current climatic conditions. The pollen spectrum dominated by Myrtaceae and Nothofagus contrasts with a strongly disturb current landscape. Actually, Purén-Lumaco valley constitutes a complex peat-bog system dominated by exotic grasses and forest species (Tritricum aestivum, Pinus radiata and Eucalyptus spp.). Some archaeological antecedents in the area document the human development at ca. 7yrs BP. The greatest archaeological characteristic present in the valley is the kuel, a Mapuche earth accumulation. The presence and extension of almost 300 kuel in the valley reflect the social/economic development, and partly explains why the region was the major resistance area for Spanish colonizer during XVI-XVII centuries. Also the archaeological findings reveal the presence of maize pollen (Zea mays) within their food consumption. The influence of climate and human impact in

  3. Frequency variations of the earth's obliquity and the 100-kyr ice-age cycles

    NASA Technical Reports Server (NTRS)

    Liu, Han-Shou

    1992-01-01

    Changes in the earth's climate are induced by variations in the earth's orbital parameters which modulate the seasonal distribution of solar radiation. Periodicities in the geological climate record with cycles of 100, 41, and 23 kyr have been linked with changes in obliquity, eccentricity, and precession of the equinoxes. The effect of variations of eccentricity during a 100 kyr period is weak relative to the signals from obliquity and precession variations and it may therefore be expected that the 100 kyr signal in the climate record would be of low intensity. However, this signal dominates the climate record and internal nonlinear processes within the climate system have previously been proposed to account for this fact. The author shows that variations in the frequency of the obliquity cycle can give rise to strong 100-kyr forcing of climate.

  4. An 84-kyr paleomagnetic record from the sediments of Lake Baikal, Siberia

    USGS Publications Warehouse

    Peck, J.A.; King, J.W.; Colman, Steven M.; Kravchinsky, V.A.

    1996-01-01

    We have conducted a paleomagnetic study of sediment cores obtained from the Selenga prodelta region of Lake Baikal, Russia. This record, which spans approximately the last 84 kyr, contributes to a better understanding of the nature of geomagnetic field behavior in Siberia and is a useful correlation and dating tool. We demonstrate that the Lake Baikal sediments are recording variations in the geomagnetic field. The directional record displays secular variation behavior with a geomagnetic excursion at 20 ka and additional excursions appearing as large-amplitude secular variation at 41, 61, and 67 ka. Smoothing of the geomagnetic excursion behavior occurs in Lake Baikal sediments owing to the intermediate sedimentation rate (13 cm kyr-1). The Lake Baikal relative paleointensity record correlates to absolute paleointensity data for the last 10 kyr and to relative paleointensity records from the Mediterranean Sea and Indian Ocean for the last 84 kyr. This correlation suggests a strong global (i.e., dipole) component to these records and further supports the reliability of sediments as recorders of relative geomagnetic paleointensity. We show that a relative geomagnetic intensity stratigraphy has a potential resolution of 7 kyr by correlating continental and marine records. The geomagnetic intensity stratigraphy helps constrain the age of the difficult to date Lake Baikal sediments.

  5. Stalagmite Survival: 500kyr of Cyclical Growth and Natural Attrition of Stalagmites in Sulawesi

    NASA Astrophysics Data System (ADS)

    Scroxton, N.; Gagan, M. K.; Dunbar, G. B.; Ayliffe, L. K.; Hantoro, W. S.; Shen, C. C.; Hellstrom, J. C.; Zhao, J. X.; Cheng, H.; Edwards, R. L.; Sun, H.; Rifai, H.

    2014-12-01

    Numerous speleothem studies have analysed the age distribution of stalagmites harvested from multiple caves and inferred important changes in paleoclimates to explain stalagmite growth phases. However, stalagmites take tens to hundreds of thousands of years to grow, and thus the twin desires to preserve the cave condition for future generations and advance palaeoclimate science are often in conflict. In this study we use U/Th ages from low impact mini-cores extracted in situ from the bases of stalagmites, thus keeping the intrinsic value of the cave intact. Our case study is based on 77 individual stalagmites drilled in situ in thirteen caves located in and around Bantimurung-Bulusaraung National Park, South Sulawesi, Indonesia. The stalagmites grew during discrete time intervals within the last ~530,000 years, and analysis of their age distribution shows an exponential decrease in the number of older stalagmites surviving to the present day. The age distribution indicates that the rate of natural attrition of stalagmites is approximately constant through time, probably in response to a number of natural processes, including downward erosion of the karst terrain, cave collapse, in-cave erosional processes and in-cave sedimentation covering stalagmites. Natural attrition of stalagmites is likely to be a general cave phenomenon, and has important implications for cave conservation because it highlights that random removal of stalagmites without prior knowledge of their ages will result in unnecessary replication and a failure to sample the full length of the available paleoclimate record. Departure from this "normal" exponential profile can be used to infer palaeoclimate information: significant deviations are produced by periods of more frequent stalagmite growth, inferred here to reflect increases in monsoon rainfall over Sulawesi (345-340, 75-70 and 10-5 kyr BP). By adjusting the record to account for stalagmite attrition, more statistically robust paleoclimate

  6. Teasing Apart Regional Climate and Meltwater Influences on Florida Straits Sea Surface Temperature and Salinity over the past 40 kyr

    NASA Astrophysics Data System (ADS)

    Schmidt, M. W.; Lynch-Stieglitz, J.

    2008-12-01

    when elevated meltwater discharge was the dominant influence on surface water conditions in the Florida Straits. It is likely that SSS in the Florida Straits was significantly fresher than today during this interval. In contrast, periods of minimal meltwater influence (such as the Younger Dryas and across D-O cycles of MIS 3) are characterized by abrupt SST and SSS shifts that covary with the NGRIP δ18Oice record. SSTs in the Florida Straits cool by 1.5-2.0 °C and regional salinity increases (IVF-δ18OSW increase of 0.5-0.7‰) at the initiation of cold stadial events as the ITCZ shifts south. The most likely explanation for these rapid shifts in IVF-δ18OSW values is that moisture transport out of the North Atlantic increases when the North Atlantic cools and the ITCZ shifts southward.

  7. Elevated BP after AKI.

    PubMed

    Hsu, Chi-yuan; Hsu, Raymond K; Yang, Jingrong; Ordonez, Juan D; Zheng, Sijie; Go, Alan S

    2016-03-01

    The connection between AKI and BP elevation is unclear. We conducted a retrospective cohort study to evaluate whether AKI in the hospital is independently associated with BP elevation during the first 2 years after discharge among previously normotensive adults. We studied adult members of Kaiser Permanente Northern California, a large integrated health care delivery system, who were hospitalized between 2008 and 2011, had available preadmission serum creatinine and BP measures, and were not known to be hypertensive or have BP>140/90 mmHg. Among 43,611 eligible patients, 2451 experienced AKI defined using observed changes in serum creatinine concentration measured during hospitalization. Survivors of AKI were more likely than those without AKI to have elevated BP--defined as documented BP>140/90 mmHg measured during an ambulatory, nonemergency department visit--during follow-up (46.1% versus 41.2% at 730 days; P<0.001). This difference was evident within the first 180 days (30.6% versus 23.1%; P<0.001). In multivariable models, AKI was independently associated with a 22% (95% confidence interval, 12% to 33%) increase in the odds of developing elevated BP during follow-up, with higher adjusted odds with more severe AKI. Results were similar in sensitivity analyses when elevated BP was defined as having at least two BP readings of >140/90 mmHg or those with evidence of CKD were excluded. We conclude that AKI is an independent risk factor for subsequent development of elevated BP. Preventing AKI during a hospitalization may have clinical and public health benefits beyond the immediate hospitalization.

  8. Ice-flow reorganization in West Antarctica 2.5 kyr ago dated using radar-derived englacial flow velocities

    NASA Astrophysics Data System (ADS)

    Kingslake, Jonathan; Martín, Carlos; Arthern, Robert J.; Corr, Hugh F. J.; King, Edward C.

    2016-09-01

    We date a recent ice-flow reorganization of an ice divide in the Weddell Sea Sector, West Antarctica, using a novel combination of inverse methods and ice-penetrating radars. We invert for two-dimensional ice flow within an ice divide from data collected with a phase-sensitive ice-penetrating radar while accounting for the effect of firn on radar propagation and ice flow. By comparing isochronal layers simulated using radar-derived flow velocities with internal layers observed with an impulse radar, we show that the divide's internal structure is not in a steady state but underwent a disturbance, potentially implying a regional ice-flow reorganization, 2.5 (1.8-2.9) kyr B.P. Our data are consistent with slow ice flow in this location before the reorganization and the ice divide subsequently remaining stationary. These findings increase our knowledge of the glacial history of a region that lacks dated constraints on late-Holocene ice-sheet retreat and provides a key target for models that reconstruct and predict ice-sheet behavior.

  9. The bioavailable iron in NEEM ice core related to Asian dust records over the past 110 kyr

    NASA Astrophysics Data System (ADS)

    Xiao, Cunde

    2016-04-01

    The mineral dust can indirectly affect climate by supplying iron and other essential bioavailable elements into ocean. In this study, we present dissolved iron (DFe) and total dissolved iron (TDFe) concentrations in NEEM ice core over the past 110 kyr B.P. The concentrations of bioavailable reactive element Fe have good positive correlation with the concentrations of dust and Ca2+ in NEEM ice core, while show significantly negative relationship with δ18O and CO2 concentration. The ratios of DFe/TDFe are higher in warm periods (Holocene and last interglacial) than in cold period (LGM), indicating the iron-biological pump effect is more significant in warm periods than that in cold periods, this result may provide a new insight for reevaluating the iron hypothesis over glacial/interglacial periods. Our study also shows that the iron flux changes between NEEM ice core and Asian loess records are good consistent with the northern Hemisphere summer insolation. These results emphasize that the variability of Fe flux is most likely driven by solar radiation and dust in northern hemisphere.

  10. Elevated BP after AKI

    PubMed Central

    Hsu, Raymond K.; Yang, Jingrong; Ordonez, Juan D.; Zheng, Sijie; Go, Alan S.

    2016-01-01

    The connection between AKI and BP elevation is unclear. We conducted a retrospective cohort study to evaluate whether AKI in the hospital is independently associated with BP elevation during the first 2 years after discharge among previously normotensive adults. We studied adult members of Kaiser Permanente Northern California, a large integrated health care delivery system, who were hospitalized between 2008 and 2011, had available preadmission serum creatinine and BP measures, and were not known to be hypertensive or have BP>140/90 mmHg. Among 43,611 eligible patients, 2451 experienced AKI defined using observed changes in serum creatinine concentration measured during hospitalization. Survivors of AKI were more likely than those without AKI to have elevated BP—defined as documented BP>140/90 mmHg measured during an ambulatory, nonemergency department visit—during follow-up (46.1% versus 41.2% at 730 days; P<0.001). This difference was evident within the first 180 days (30.6% versus 23.1%; P<0.001). In multivariable models, AKI was independently associated with a 22% (95% confidence interval, 12% to 33%) increase in the odds of developing elevated BP during follow-up, with higher adjusted odds with more severe AKI. Results were similar in sensitivity analyses when elevated BP was defined as having at least two BP readings of >140/90 mmHg or those with evidence of CKD were excluded. We conclude that AKI is an independent risk factor for subsequent development of elevated BP. Preventing AKI during a hospitalization may have clinical and public health benefits beyond the immediate hospitalization. PMID:26134154

  11. Orbitally paced paleoproductivity variations in the Timor Sea and Indonesian Throughflow variability during the last 460 kyr

    NASA Astrophysics Data System (ADS)

    Holbourn, Ann; Kuhnt, Wolfgang; Kawamura, Hiroshi; Jian, Zhimin; Grootes, Piet; Erlenkeuser, Helmut; Xu, Jian

    2005-09-01

    A high-resolution (˜1-2 kyr) multiproxy record from the Timor Sea in the easternmost Indian Ocean (International Marine Global Change (IMAGES) Program Core MD01-2378, latitude 13°04.95'S, longitude 121°47.27'E, 1783 m water depth) closely tracks changes in intermediate water ventilation and paleoproductivity over the last 460 kyr within one of the main outflow passages of the Indonesian Throughflow. Spectral analysis of five different flux-based productivity proxies indicates spectral power concentrated in the 100 kyr (glacial-interglacial) and the 23 kyr and 19 kyr (precessional) periods. Paleoproductivity maxima lead ice volume (benthic δ18O) maxima by 20° to 40° (˜1300 to 2600 years) at the precession band. The spectral differences in tropical paleoproductivity records from the Pacific and Indian oceans suggest that local processes (wind and circulation patterns driven by insolation) are dominant in driving productivity rather than large-scale tropical features. In the Timor Sea, productivity fluctuations over the last 460 kyr were strongly influenced by monsoonal wind patterns offshore NW Australia (23 and 19 kyr) and were also modulated by sea level-related variations in the intensity of the Indonesian Throughflow (100 kyr).

  12. Geomagnetic intensity variations over the past 780 kyr obtained from near-seafloor magnetic anomalies.

    PubMed

    Gee, J S; Cande, S C; Hildebrand, J A; Donnelly, K; Parker, R L

    2000-12-14

    Knowledge of past variations in the intensity of the Earth's magnetic field provides an important constraint on models of the geodynamo. A record of absolute palaeointensity for the past 50 kyr has been compiled from archaeomagnetic and volcanic materials, and relative palaeointensities over the past 800 kyr have been obtained from sedimentary sequences. But a long-term record of geomagnetic intensity should also be carried by the thermoremanence of the oceanic crust Here we show that near-seafloor magnetic anomalies recorded over the southern East Pacific Rise are well correlated with independent estimates of geomagnetic intensity during the past 780 kyr. Moreover, the pattern of absolute palaeointensity of seafloor glass samples from the same area agrees with the well-documented dipole intensity pattern for the past 50 kyr. A comparison of palaeointensities derived from seafloor glass samples with global intensity variations thus allows us to estimate the ages of surficial lava flows in this region. The record of geomagnetic intensity preserved in the oceanic crust should provide a higher-time-resolution record of crustal accretion processes at mid-ocean ridges than has previously been obtainable.

  13. Changes in Phytoplankton Community Structure in Western South China Sea Over the Past 450 Kyrs

    NASA Astrophysics Data System (ADS)

    Li, L.; Wang, H.; Li, J.; Zhao, M.; Wang, P.; Zhang, C.

    2008-12-01

    Molecular biomarkers (brassicasterol, dinosterol, alkenones, C30 1,15-diol/keto-ol and cholesterol) were measured in an IMAGES core MD05-2901 (14°22.50'N, 110°44.60'E, w.d. 1454 m), to reconstruct the phytoplankton community structure over the past 450 kyrs in the western South China Sea on the eastern slope off Vietnam. Our results showed that diatoms, which are most sensitive to nutrition supply, exhibited relatively high productivity in interglacial period and lower productivity in glacial period, possibly caused by summer monsoon-induced upwelling. Dinoflagellates exhibited simillar phenomena as diatoms. But, coccolithphorids did not show clear glacial/intergalcial patterns and had a gradual increasing trend from 450 kyrs to 200 kyrs followed by a gradual decreasing trend until the present. Eustigmatophytes exhibited higher contents in glacial than interglacial periods and almost the same variations with terrestrial n- alkanes. Relationships among the major biomarker groups indicated complex responses of different phytoplanktons to changes in paleoclimate and paleoenvironment in the past 450 kyrs in western South China Sea.

  14. Investigating the Impacts of Climate, Hydrology, and Asian Monsoon Intensity on a 13 kyr Speleothem Record from Laos

    NASA Astrophysics Data System (ADS)

    Yang, Hongying

    I present a high- resolution record of Southeast Asian Monsoon (SEAM) evolution compiled from delta18O measurements conducted on five U-Th dated speleothems from Tham Mai Cave in northern Laos (20.75N, 102.65E), a key site at the interface between the Indian and East Asian monsoon systems. The speleothem oxygen isotope records are tied to robust uranium-series dates and indicate the records span from 0.79 to 13 kyr BP with sub-decadal resolution. During the Holocene, the Tham Mai speleothem delta18O records are characterized by lower values during the early to mid-Holocene with increasing values towards the late Holocene. This is similar to trends seen throughout the Asian monsoon region, reflecting the strong insolation control on monsoon strength and ITCZ position. The Younger Dryas is characterized by an abrupt delta 18O increase and is synchronous with the even observed in Chinese speleothem records and Greenland ice cores within age uncertainties. This suggests that the SEAM weakened in sync with high-latitude abrupt cooling events. Four speleothems from Tham Mai cave grew contemporaneously from 4,300 years BP to 9,000 years BP. These four samples show a similar delta 18O pattern, despite a 1.2‰ between sample delta18 O variability is observed. A lumped parameter forward model method (KarstFor model) is used to assess to which extent this 1.2‰ discrepancy can be attributed to hydrological variability. Results suggested that this 1.2‰ discrepancy can be generated due to hydrological variability within one cave. To better interpret interannual delta18O variability in high-resolution oxygen isotope records in the Asian Monsoon region, I utilize existing simulations from a spectrally nudged isotope-enabled general circulation model (IsoGSM) to investigate the climatic controls on delta18 Op at four cave locations along the Asian monsoon region. Results show that delta18Op at the four cave sites reflects large-scale ocean-atmosphere processes, instead of

  15. 78 FR 60270 - BP America Inc., BP Corporation North America Inc., BP America Production Company, and BP Energy...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-01

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission BP America Inc., BP Corporation North America Inc., BP America Production Company, and BP Energy Company; Notice of Designation of Commission Staff as Non-Decisional With respect to an order issued by the Commission...

  16. Geochemistry of the Black Sea during the last 15 kyr: A protracted evolution of its hydrography and ecology

    USGS Publications Warehouse

    Piper, David Z.

    2016-01-01

    The Black Sea is a 2200 m deep anoxic, marine sea connected to the Mediterranean Sea via the Dardanelles Strait, Marmara Sea, and the 3 km wide, 35 m deep Bosphorus Strait. The biogeochemistry of sediment from the Anatolia slope has recorded changes to the hydrography leading up to and following the input of Mediterranean water at ~9.4 ka (103 years B.P.), when global sea level rose to the level of the Bosphorus sill and high-salinity water from the Mediterranean began to spill into the then brackish lake. The water initially mixed little with the lake water but cascaded to the bottom where it remained essentially isolated for ~1.6 kyr, the time required to fill the basin from the bottom up at its present input rate. The accumulation of Mo in the seafloor sediments, a proxy of bottom-water anoxia, increased sharply at ~8.6 ka, when bacterial respiration in the bottom water advanced to SO42− reduction by the oxidation of organic detritus that settled out of the photic zone. Its accumulation remained elevated to ~5.6 ka, when it decreased 60%, only to again increase slightly at ~2.0 ka. The accumulation of Corg, a proxy of primary productivity, increased threefold to fourfold at ~7.8 ka, when upward mixing of the high-salinity bottom water replaced the then thin veneer of the brackish photic zone in less than 50 years. From that time onward, the accumulation of Corg, Mo, and additional trace metals has reflected the hydrography of the basin and Bosphorus Strait, controlled largely by climate.

  17. Geochemistry of the Black Sea during the last 15 kyr: A protracted evolution of its hydrography and ecology

    NASA Astrophysics Data System (ADS)

    Piper, D. Z.

    2016-08-01

    The Black Sea is a 2200 m deep anoxic, marine sea connected to the Mediterranean Sea via the Dardanelles Strait, Marmara Sea, and the 3 km wide, 35 m deep Bosphorus Strait. The biogeochemistry of sediment from the Anatolia slope has recorded changes to the hydrography leading up to and following the input of Mediterranean water at ~9.4 ka (103 years B.P.), when global sea level rose to the level of the Bosphorus sill and high-salinity water from the Mediterranean began to spill into the then brackish lake. The water initially mixed little with the lake water but cascaded to the bottom where it remained essentially isolated for ~1.6 kyr, the time required to fill the basin from the bottom up at its present input rate. The accumulation of Mo in the seafloor sediments, a proxy of bottom-water anoxia, increased sharply at ~8.6 ka, when bacterial respiration in the bottom water advanced to SO42- reduction by the oxidation of organic detritus that settled out of the photic zone. Its accumulation remained elevated to ~5.6 ka, when it decreased 60%, only to again increase slightly at ~2.0 ka. The accumulation of Corg, a proxy of primary productivity, increased threefold to fourfold at ~7.8 ka, when upward mixing of the high-salinity bottom water replaced the then thin veneer of the brackish photic zone in less than 50 years. From that time onward, the accumulation of Corg, Mo, and additional trace metals has reflected the hydrography of the basin and Bosphorus Strait, controlled largely by climate.

  18. A distal 140 kyr sediment record of Nile discharge and East African monsoon variability

    NASA Astrophysics Data System (ADS)

    Ehrmann, Werner; Schmiedl, Gerhard; Seidel, Martin; Krüger, Stefan; Schulz, Hartmut

    2016-03-01

    Clay mineral assemblages in a sediment core from the distal Nile discharge plume off Israel have been used to reconstruct the late Quaternary Nile sediment discharge into the eastern Mediterranean Sea (EMS). The record spans the last ca. 140 kyr. Smectite abundances indicate the influence of the Blue Nile and the Atbara River that have their headwaters in the volcanic rocks of the Ethiopian Highlands. Kaolinite abundances indicate the influence of wadis, which contribute periodically to the suspension load of the Nile. Due to the geographical position, the climate and the sedimentary framework of the EMS is controlled by two climate systems. The long-term climate regime was governed by the African monsoon that caused major African humid periods (AHPs) with enhanced sediment discharge at 132 to < 126 (AHP 5), 116 to 99 (AHP4), and 89 to 77 ka (AHP3). They lasted much longer than the formation of the related sapropel layers S5 (> 2 kyr), S4 (3.5 kyr), and S3 (5 kyr). During the last glacial period (Marine Isotope Stages (MISs) 4-2), the long-term changes in the monsoonal system were superimposed by millennial-scale changes in an intensified midlatitude glacial system. This climate regime caused short but pronounced drought periods in the Nile catchment, which are linked to Heinrich events and alternate with more humid interstadials. The clay mineral record further implies that feedback mechanisms between vegetation cover and sediment discharge of the Nile are detectable but of minor importance for the sedimentary record in the southeastern Mediterranean Sea during the investigated African humid periods.

  19. Blood pressure (BP) assessment-from BP level to BP variability.

    PubMed

    Feber, Janusz; Litwin, Mieczyslaw

    2016-07-01

    The assessment of blood pressure (BP) can be challenging in children, especially in very young individuals, due to their variable body size and lack of cooperation. In the absence of data relating BP with cardiovascular outcomes in children, there is a need to convert absolute BP values (in mmHg) into age-, gender- and height appropriate BP percentiles or Z-scores in order to compare a patient's BP with the BP of healthy children of the same age, but also of children of different ages. Traditionally, the interpretation of BP has been based mainly on the assessment of the BP level obtained by office, home or 24-h BP monitoring. Recent studies suggest that it is not only BP level (i.e. average BP) but also BP variability that is clinically important for the development of target organ damage, including the progression of chronic kidney disease. In this review we describe current methods to evaluate of BP level, outline available methods for BP variability assessment and discuss the clinical consequences of BP variability, including its potential role in the management of hypertension.

  20. Causal links between Nile floods and eastern Mediterranean sapropel formation during the past 125 kyr confirmed by OSL and radiocarbon dating of Blue and White Nile sediments

    NASA Astrophysics Data System (ADS)

    Williams, M. A. J.; Duller, G. A. T.; Williams, F. M.; Woodward, J. C.; Macklin, M. G.; El Tom, O. A. M.; Munro, R. N.; El Hajaz, Y.; Barrows, T. T.

    2015-12-01

    It has long been hypothesised that beds of highly organic mud or sapropels seen in marine sediment cores retrieved from the floor of the eastern Mediterranean accumulated during times of high Nile fluvial discharge. Our recent fieldwork in the valleys of the Blue Nile, the White Nile and the main Nile has for the first time revealed a sequence of extreme flood episodes synchronous with sapropel units S5 (124 kyr), S4 (102 kyr), S3 (81 kyr), S2 (55 kyr) and S1 (13.5-6.5 kyr). There are more weakly defined links with Nile floods and sapropel units S9 (240 kyr), S8 (217 kyr), S7 (195 kyr), S6 (172 kyr), but the dating error terms are too large to allow us to be too definite. During times of extreme floods over the past 125 kyr, wide distributary channels of the Blue Nile flowed across the Gezira alluvial fan in central Sudan and transported a bed load of sand and gravel into the lower White Nile valley. The sands were reworked by wind to form source-bordering dunes, all of which contain heavy minerals of Ethiopian provenance. These source-bordering dunes were active at 115-105 kyr, 60 kyr and 12-7 kyr, all times of extreme Blue Nile floods. The flood and dune sediments were dated using a combination of optically stimulated luminescence (OSL) and radiocarbon analyses. The Quaternary record of Nile floods discussed here shows a precessional signal and reflects episodes of stronger summer monsoon and more northerly seasonal movement of the ITCZ, linked to times of higher insolation in northern tropical latitudes. Progressive aggradation of Holocene Nile channels in northern Sudan has had a profound influence upon human settlement in the last 8 kyr.

  1. Deep water circulation in the eastern Mediterranean Sea for the last 95 kyr: new insights from stable isotopes and benthic foraminiferal assemblages

    NASA Astrophysics Data System (ADS)

    Cornuault, Marine; Vidal, Laurence; Tachikawa, Kazuyo; Licari, Laetitia; Rouaud, Guillaume; Sonzogni, Corinne; Revel, Marie

    2016-04-01

    The response of the Eastern Mediterranean Sea circulation to climate forcing over the last 95 kyr BP was studied using core MD04-2722 collected at 1780m water depth in the Levantine Sea. Foraminiferal stable isotopes and benthic foraminiferal assemblages were combined to reconstruct deep water ventilation and oxygenation in relation to surface water freshening. Over the last deglaciation, benthic foraminiferal δ13C values and benthic foraminiferal oxygen index decreased while δ18O gradient between benthic and planktonic foraminifera increased. These results testify respectively of slower ventilation, bottom water oxygen depletion and stronger stratification prior to S1 sapropel deposition. Similar conditions were deduced for S3 sapropel. Combination of deglacial sea level rise and fresher North Atlantic surface water contribution were evaluated to be a precondition of S1 formation in the Levantine Sea. Local Nile freshwater supply during the African Humid Period further strengthened the water column stratification. For the last glacial period, three events at around 53, 46 and 37 ka BP were marked by benthic δ13C decrease demonstrating deep water circulation reduction at the core location. Bottom water oxygenation was only slightly lowered. Considering the effect of North Atlantic surface water salinity to the Mediterranean Sea circulation, we propose the 46 and 37 ka BP events as responses to the Heinrich Events 4 and 5 that supplied fresher surface water to the Mediterranean Sea. Since the '53 ka event' is characterized by the appearance of an anoxic benthic foraminiferal species observed for S1 and S3 layers, we tentatively attributed it to the 'missing' sapropel S2. Our results indicate that intense stagnation in the Eastern Mediterranean Sea could occur when both local freshwater supply and fresher North Atlantic surface water contributed. The influence of North Atlantic condition was significant on the eastern Mediterranean circulation under warm and cold

  2. Grain-size based sea-level reconstruction in the south Bohai Sea during the past 135 kyr

    NASA Astrophysics Data System (ADS)

    Yi, Liang; Chen, Yanping

    2013-04-01

    marine surface and core samples, and to quantitatively reconstruct sea-level variation since the late Pleistocene in the south Bohai Sea, China. New insights into regional relative sea-level changes since the late Pleistocene are obtained (Yi et al., 2012): (1) The grain size of surface and core samples can be mathematically partitioned using the Weibull distribution into four components. These four components with differing modal sizes and percentages could be interpreted as a long-term suspension component, which only settles under low turbulence conditions, sortable silt and very fine sand components transported by suspension during greater turbulence and bedload transport component, respectively. (2) Through regression and rigorous verification techniques, the reference water level could be reconstructed from sediment grain size. The reconstruction quantitatively extends the regional relative sea-level history to the late Pleistocene, providing a comparatively long dataset to evaluate regional sea-level variability. (3) We find no evidence of a sea-level high stand during MIS3 but rather a substantial regression during 70-30 cal kyr BP and potentially exposed land during 38-20 cal kyr BP. These results for the south Bohai Sea are in good agreement with published global sea-level records for the late Pleistocene, implying similarities between local and global sea-level patterns. Therefore, it is concluded that grain-size based sea-level reconstruction provide results that are comparable to other reconstruction methods and demonstrates great potential application for future works. (The data was shared on http://hurricane.ncdc.noaa.gov/) References Chappell, J., Omura, A., Esat, T., McCulloch, M., Pandolfi, J., Ota, Y., Pillans, B., 1996. Reconciliation of late Quaternary sea levels derived from coral terraces at Huon Peninsula with deep sea oxygen isotope records. Earth and Planetary Science Letters 141, 227-236. Chappell, J., Shackleton, N.J., 1986. Oxygen isotopes

  3. The Liang Bua faunal remains: a 95k.yr. sequence from Flores, East Indonesia.

    PubMed

    van den Bergh, G D; Meijer, H J M; Due Awe, Rokhus; Morwood, M J; Szabó, K; van den Hoek Ostende, L W; Sutikna, T; Saptomo, E W; Piper, P J; Dobney, K M

    2009-11-01

    Excavations at Liang Bua, a limestone cave on the island of Flores, East Indonesia, have yielded a well-dated archaeological and faunal sequence spanning the last 95k.yr., major climatic fluctuations, and two human species -H. floresiensis from 95 to 17k.yr.(1), and modern humans from 11k.yr. to the present. The faunal assemblage comprises well-preserved mammal, bird, reptile and mollusc remains, including examples of island gigantism in small mammals and the dwarfing of large taxa. Together with evidence from Early-Middle Pleistocene sites in the Soa Basin, it confirms the long-term isolation, impoverishment, and phylogenetic continuity of the Flores faunal community. The accumulation of Stegodon and Komodo dragon remains at the site in the Pleistocene is attributed to Homo floresiensis, while predatory birds, including an extinct species of owl, were largely responsible for the accumulation of the small vertebrates. The disappearance from the sequence of the two large-bodied, endemic mammals, Stegodon florensis insularis and Homo floresiensis, was associated with a volcanic eruption at 17 ka and precedes the earliest evidence for modern humans, who initiated use of mollusc and shell working, and began to introduce a range of exotic animals to the island. Faunal introductions during the Holocene included the Sulawesi warty pig (Sus celebensis) at about 7ka, followed by the Eurasian pig (Sus scrofa), Long-tailed macaque, Javanese porcupine, and Masked palm civet at about 4ka, and cattle, deer, and horse - possibly by the Portuguese within historic times. The Holocene sequence at the site also documents local faunal extinctions - a result of accelerating human population growth, habitat loss, and over-exploitation.

  4. Environmental Magnetic Record of the past 220 kyr from Timor Sea

    NASA Astrophysics Data System (ADS)

    Oda, H.; Yokoyama, Y.; Satoshi, H.

    2007-12-01

    Environmental magnetic study was conducted on long piston core MD05-2970 from Timor Sea off northwest of Australia during IMAGES cruise. The site is located at Lat. 9°25'00S and Lon. 130°60'00E with a water depth of 437 m and the total length of the core is 29.82 m. Sediment consists of calcarious silt to clay with abundant foraminifera. 14C and oxygen isotope measurements revealed that the core preserved 220 kyr long record and that the sedimentation rates range from 18 cm/kyr at the top to 10 cm/kyr at the bottom. Intensity of natural remanent magnetization is reduced two orders of magnitude by diagenetic dissolution of magnetic minerals below 0.3 mbsf, which resulted in a poor paleomagnetic record. There are some horizons which show reversed or intermediate polarity directions with higher magnetization intensity and higher coercivity compared with the adjacent samples. This can be interpreted as CRM acquired in the direction different from the Earth's magnetic field. Low temperature magnetometry and thermal demagnetization of composite IRM revealed that dominant magnetic mineral is magnetite with trace amount of hematite. Zone of dissolution is characterized by downward decrease in Sratio to 0.7 mbsf and subsequent increase to 2 mbsf. This can be interpreted as an initial dissolution of fine grained (possibly biogenic) magnetite and subsequent dissolution of hematite below 0.7 mbsf. Median destructive field of ARM is lower (~15 mT) during marine oxygen isotope stage (MIS) 7 compared with the values above. Grain size parameters also show relatively higher values (finer grained) and paleomagnetic directions are defined better (smaller MAD values) for MIS 7. These indicate that finer grained magnetic minerals deposited or remained during MIS 7, which might have been resulted from environmental change between MIS 7 and later stages.

  5. Geomagnetic field intensity, North Atlantic Deep Water circulation and atmospheric Δ 14C during the last 50 kyr

    NASA Astrophysics Data System (ADS)

    Laj, Carlo; Kissel, Catherine; Mazaud, Alain; Michel, Elisabeth; Muscheler, Raimund; Beer, Juerg

    2002-06-01

    We present simulated records of past changes in the atmospheric Δ 14C for the last 50 kyr due to changes in geomagnetic field intensity and in the strength of the North Atlantic Deep Water (NADW). A new geomagnetic record was used, largely based on the NAPIS-75 record [Laj et al., Phil. Trans. R. Soc. London A 358 (2000) 1009-1025] which has been extended for the 0-20 kyr interval using archeomagnetic and volcanic data. Past changes of the NADW were derived from a mineral magnetic study of the cores used in the construction of NAPIS-75. Two box models of different complexity (4 and 17 boxes) were used to simulate the carbon cycle. Calculated records of Δ 14C are consistent with experimental determinations for the last 24 kyr. For older ages, the records calculated with variable oceanic circulation conditions reach values as high as 600‰ (with an average of 500‰) between 20 and 40 kyr with maxima around 21, 30 and 38 kyr (GISP2 age model), while low values are observed prior to 42 kyr. Although large inconsistencies in experimental data preclude precise comparison, the average record simulated with the 17-box model is overall consistent with the Icelandic Sea record [Voelker et al., Radiocarbon 40 (1998) 517-534; 42 (2000) 437-452], except for the extremely high peak observed in this record at 40.5 kyr. On the other hand, the results recently reported from a stalagmite recovered from a submerged cave in the Bahamas [Beck et al., Science 292 (2001) 2453-2458] are inconsistent with all our model simulations. In the 20-45 kyr interval, the improved geomagnetic record combined with the new NADW profile allows us to give a modeled evaluation of the relative contribution of these factors to changes in atmospheric Δ 14C. The average simulation provides a first order modeled correction for conventional radiocarbon ages older than 25 kyr for which no calibration curve is available as yet.

  6. Infrastructure Upgrades to Support Model Longevity and New Applications: The Variable Infiltration Capacity Model Version 5.0 (VIC 5.0)

    NASA Astrophysics Data System (ADS)

    Nijssen, B.; Hamman, J.; Bohn, T. J.

    2015-12-01

    The Variable Infiltration Capacity (VIC) model is a macro-scale semi-distributed hydrologic model. VIC development began in the early 1990s and it has been used extensively, applied from basin to global scales. VIC has been applied in a many use cases, including the construction of hydrologic data sets, trend analysis, data evaluation and assimilation, forecasting, coupled climate modeling, and climate change impact analysis. Ongoing applications of the VIC model include the University of Washington's drought monitor and forecast systems, and NASA's land data assimilation systems. The development of VIC version 5.0 focused on reconfiguring the legacy VIC source code to support a wider range of modern modeling applications. The VIC source code has been moved to a public Github repository to encourage participation by the model development community-at-large. The reconfiguration has separated the physical core of the model from the driver, which is responsible for memory allocation, pre- and post-processing and I/O. VIC 5.0 includes four drivers that use the same physical model core: classic, image, CESM, and Python. The classic driver supports legacy VIC configurations and runs in the traditional time-before-space configuration. The image driver includes a space-before-time configuration, netCDF I/O, and uses MPI for parallel processing. This configuration facilitates the direct coupling of streamflow routing, reservoir, and irrigation processes within VIC. The image driver is the foundation of the CESM driver; which couples VIC to CESM's CPL7 and a prognostic atmosphere. Finally, we have added a Python driver that provides access to the functions and datatypes of VIC's physical core from a Python interface. This presentation demonstrates how reconfiguring legacy source code extends the life and applicability of a research model.

  7. 100 Kyr Old Desert of Western India: Morhodynamics and Environmental Significance

    NASA Astrophysics Data System (ADS)

    Bhatt, N.

    2012-04-01

    The Late Quaternary oscillations in sea levels and resultant changes in the coastal environment have remained a popular aspect of study amongst the earthscientists and archaeologists. The Saurashtra peninsula of the western India that lies on the southwestern side of the Thar Desert, has archived a fascinating record of such environmental changes since last interglacial (~120kyr) in the form of a fossil desert exhibiting various aeolian land forms constituted by the sand largely derived from the coastal areas due to an oscillatory sea level change. A variety of dunes viz., coastal transverse, parabolic, longitudinal, barchans, climbing and falling dunes along with valley fills and sand sheets have been mapped. Being biogenic calcium carbonate rich, the sands have been lithified under the influence of an increase in moisture and thus the dune and bed forms are preserved in its best shape. The intense aeolian activities are also evident in the form of desert varnish on rocky outcrops. The sequence comprises smaller climate perturbations in the form of stabilization, erosion and karstification of older dunes and deposition of fluvial sediments in between. The paper deals with the mode of occurrence, response of sediments to wind dynamics and palaeo topography, internal structures, later modifications of sediments and significance of the geochronologically constrained aeolianites in understanding of environmental changes since 100kyr in the region.

  8. Variations in the geomagnetic dipole moment during the Holocene and the past 50 kyr

    NASA Astrophysics Data System (ADS)

    Knudsen, Mads Faurschou; Riisager, Peter; Donadini, Fabio; Snowball, Ian; Muscheler, Raimund; Korhonen, Kimmo; Pesonen, Lauri J.

    2008-07-01

    All absolute paleointensity data published in peer-reviewed journals were recently compiled in the GEOMAGIA50 database. Based on the information in GEOMAGIA50, we reconstruct variations in the geomagnetic dipole moment over the past 50 kyr, with a focus on the Holocene period. A running-window approach is used to determine the axial dipole moment that provides the optimal least-squares fit to the paleointensity data, whereas associated error estimates are constrained using a bootstrap procedure. We subsequently compare the reconstruction from this study with previous reconstructions of the geomagnetic dipole moment, including those based on cosmogenic radionuclides ( 10Be and 14C). This comparison generally lends support to the axial dipole moments obtained in this study. Our reconstruction shows that the evolution of the dipole moment was highly dynamic, and the recently observed rates of change (5% per century) do not appear unique. We observe no apparent link between the occurrence of archeomagnetic jerks and changes in the geomagnetic dipole moment, suggesting that archeomagnetic jerks most likely represent drastic changes in the orientation of the geomagnetic dipole axis or periods characterized by large secular variation of the non-dipole field. This study also shows that the Holocene geomagnetic dipole moment was high compared to that of the preceding ˜ 40 kyr, and that ˜ 4 · 10 22 Am 2 appears to represent a critical threshold below which geomagnetic excursions and reversals occur.

  9. Glacial lake drainage in Patagonia (13-8 kyr) and response of the adjacent Pacific Ocean

    PubMed Central

    Glasser, Neil F.; Jansson, Krister N.; Duller, Geoffrey A. T.; Singarayer, Joy; Holloway, Max; Harrison, Stephan

    2016-01-01

    Large freshwater lakes formed in North America and Europe during deglaciation following the Last Glacial Maximum. Rapid drainage of these lakes into the Oceans resulted in abrupt perturbations in climate, including the Younger Dryas and 8.2 kyr cooling events. In the mid-latitudes of the Southern Hemisphere major glacial lakes also formed and drained during deglaciation but little is known about the magnitude, organization and timing of these drainage events and their effect on regional climate. We use 16 new single-grain optically stimulated luminescence (OSL) dates to define three stages of rapid glacial lake drainage in the Lago General Carrera/Lago Buenos Aires and Lago Cohrane/Pueyrredón basins of Patagonia and provide the first assessment of the effects of lake drainage on the Pacific Ocean. Lake drainage occurred between 13 and 8 kyr ago and was initially gradual eastward into the Atlantic, then subsequently reorganized westward into the Pacific as new drainage routes opened up during Patagonian Ice Sheet deglaciation. Coupled ocean-atmosphere model experiments using HadCM3 with an imposed freshwater surface “hosing” to simulate glacial lake drainage suggest that a negative salinity anomaly was advected south around Cape Horn, resulting in brief but significant impacts on coastal ocean vertical mixing and regional climate. PMID:26869235

  10. Glacial lake drainage in Patagonia (13-8 kyr) and response of the adjacent Pacific Ocean.

    PubMed

    Glasser, Neil F; Jansson, Krister N; Duller, Geoffrey A T; Singarayer, Joy; Holloway, Max; Harrison, Stephan

    2016-02-12

    Large freshwater lakes formed in North America and Europe during deglaciation following the Last Glacial Maximum. Rapid drainage of these lakes into the Oceans resulted in abrupt perturbations in climate, including the Younger Dryas and 8.2 kyr cooling events. In the mid-latitudes of the Southern Hemisphere major glacial lakes also formed and drained during deglaciation but little is known about the magnitude, organization and timing of these drainage events and their effect on regional climate. We use 16 new single-grain optically stimulated luminescence (OSL) dates to define three stages of rapid glacial lake drainage in the Lago General Carrera/Lago Buenos Aires and Lago Cohrane/Pueyrredón basins of Patagonia and provide the first assessment of the effects of lake drainage on the Pacific Ocean. Lake drainage occurred between 13 and 8 kyr ago and was initially gradual eastward into the Atlantic, then subsequently reorganized westward into the Pacific as new drainage routes opened up during Patagonian Ice Sheet deglaciation. Coupled ocean-atmosphere model experiments using HadCM3 with an imposed freshwater surface "hosing" to simulate glacial lake drainage suggest that a negative salinity anomaly was advected south around Cape Horn, resulting in brief but significant impacts on coastal ocean vertical mixing and regional climate.

  11. Glacial lake drainage in Patagonia (13-8 kyr) and response of the adjacent Pacific Ocean

    NASA Astrophysics Data System (ADS)

    Glasser, Neil F.; Jansson, Krister N.; Duller, Geoffrey A. T.; Singarayer, Joy; Holloway, Max; Harrison, Stephan

    2016-02-01

    Large freshwater lakes formed in North America and Europe during deglaciation following the Last Glacial Maximum. Rapid drainage of these lakes into the Oceans resulted in abrupt perturbations in climate, including the Younger Dryas and 8.2 kyr cooling events. In the mid-latitudes of the Southern Hemisphere major glacial lakes also formed and drained during deglaciation but little is known about the magnitude, organization and timing of these drainage events and their effect on regional climate. We use 16 new single-grain optically stimulated luminescence (OSL) dates to define three stages of rapid glacial lake drainage in the Lago General Carrera/Lago Buenos Aires and Lago Cohrane/Pueyrredón basins of Patagonia and provide the first assessment of the effects of lake drainage on the Pacific Ocean. Lake drainage occurred between 13 and 8 kyr ago and was initially gradual eastward into the Atlantic, then subsequently reorganized westward into the Pacific as new drainage routes opened up during Patagonian Ice Sheet deglaciation. Coupled ocean-atmosphere model experiments using HadCM3 with an imposed freshwater surface “hosing” to simulate glacial lake drainage suggest that a negative salinity anomaly was advected south around Cape Horn, resulting in brief but significant impacts on coastal ocean vertical mixing and regional climate.

  12. Chandra Observations of the Crab-like Supernova Remnant G21.5-0.9.

    PubMed

    Slane; Chen; Schulz; Seward; Hughes; Gaensler

    2000-04-10

    Chandra observations of the Crab-like supernova remnant G21.5-0.9 reveal a compact central core and spectral variations indicative of synchrotron burn-off of higher energy electrons in the inner nebula. The central core is slightly extended, perhaps indicating the presence of an inner wind-shock nebula surrounding the pulsar. No pulsations are observed from the central region, yielding an upper limit of approximately 40% for the pulsed fraction. A faint outer shell may be the first evidence of the expanding ejecta and blast wave formed in the initial explosion, indicating a composite nature for G21.5-0.9.

  13. A high-resolution mid-Pleistocene temperature record from Arctic Lake El'gygytgyn: a 50 kyr super interglacial from MIS 33 to MIS 31?

    NASA Astrophysics Data System (ADS)

    de Wet, Gregory A.; Castañeda, Isla S.; DeConto, Robert M.; Brigham-Grette, Julie

    2016-02-01

    Previous periods of extreme warmth in Earth's history are of great interest in light of current and predicted anthropogenic warming. Numerous so called ;super interglacial; intervals, with summer temperatures significantly warmer than today, have been identified in the 3.6 million year (Ma) sediment record from Lake El'gygytgyn, northeast Russia. To date, however, a high-resolution paleotemperature reconstruction from any of these super interglacials is lacking. Here we present a paleotemperature reconstruction based on branched glycerol dialkyl glycerol tetraethers (brGDGTs) from Marine Isotope Stages (MIS) 35 to MIS 29, including super interglacial MIS 31. To investigate this period in detail, samples were analyzed with an unprecedented average sample resolution of 500 yrs from MIS 33 to MIS 30. Our results suggest the entire period currently defined as MIS 33-31 (∼1114-1062 kyr BP) was characterized by generally warm and highly variable conditions at the lake, at times out of phase with Northern Hemisphere summer insolation, and that cold ;glacial; conditions during MIS 32 lasted only a few thousand years. Close similarities are seen with coeval records from high southern latitudes, supporting the suggestion that the interval from MIS 33 to MIS 31 was an exceptionally long interglacial (Teitler et al., 2015). Based on brGDGT temperatures from Lake El'gygytgyn (this study and unpublished results), warming in the western Arctic during MIS 31 was matched only by MIS 11 during the Pleistocene.

  14. PSR J1833-1034: Discovery of the Central Young Pulsar in the Supernova Remnant G21.5-0.9

    NASA Astrophysics Data System (ADS)

    Camilo, F.; Ransom, S. M.; Gaensler, B. M.; Slane, P. O.; Lorimer, D. R.; Reynolds, J.; Manchester, R. N.; Murray, S. S.

    2006-01-01

    We have discovered the pulsar associated with the supernova remnant G21.5-0.9. PSR J1833-1034, with spin period P=61.8 ms and dispersion measure 169 cm-3 pc, is very faint, with pulse-averaged flux density of ~70 μJy at a frequency of 1.4 GHz, and was first detected in a deep search with the Parkes telescope. Subsequent observations with Parkes and the Green Bank Telescope have confirmed this detection and yield a period derivative P˙=2.02×10-13. These spin parameters imply a characteristic age τc=4.8 kyr and a spin-down luminosity E˙=3.3×1037 ergs s-1, the latter value exceeded only by the Crab pulsar among the rotation-powered pulsars known in our Galaxy. The pulsar has an unusually steep radio spectrum in the 0.8-2.0 GHz range, with power-law index ~3.0, and a narrow single-peaked pulse profile with FWHM of 0.04P. We have analyzed 350 ks of archival Chandra X-Ray Observatory HRC data and find a pointlike source of luminosity ~3×10-5E˙, offset from the center of an elliptical region of size ~7''×5'' and luminosity ~10-3E˙ within which likely lies the pulsar wind termination shock. We have searched for X-ray pulsations in a 30 ks HRC observation without success, deriving a pulsed fraction upper limit for a sinusoidal pulse shape of about 70% of the pulsar flux. We revisit the distance to G21.5-0.9 based on H I and CO observations, arguing that it is 4.7+/-0.4 kpc. We use existing X-ray and radio observations of the pulsar wind nebula, along with the measured properties of its engine and a recent detection of the supernova remnant shell, to argue that G21.5-0.9 and PSR J1833-1034 are much younger than τc and likely their true age is <~1000 yr. In that case, the initial spin period of the pulsar was >~55 ms.

  15. Automated Interactive Simulation Model (AISIM) VAX Version 5.0 User’s Manual.

    DTIC Science & Technology

    1987-05-29

    CREATING VJDRKIN% DATABASF ..... Followed by: ..... COPY COMPL&ETE The DUIt prompt (*) will appear when the system is ready to accept coriands at the D(1I...IN EFFECT: VERSION: PRODUCTION VERSION 5.0 TER i N AL: Terminal type specified in command or default PROaJECf: Project specified in coriand or default

  16. Changes in chemical weathering intensity in the Himalayas over the past 30 kyr

    NASA Astrophysics Data System (ADS)

    Dosseto, A.; Vigier, N.

    2010-12-01

    Chemical weathering and climate are tightly coupled and in an era of rapid climate change, it is critical to be able to understand how erosion processes respond to climate variability. A possible approach is to investigate sedimentary records and study how in the past, sediments have recorded the response of catchment erosion to climate variability. In this study, we have measured lithium (Li) isotopes in sediments deposited on river terraces in the upper Ganges (Alaknanda) and Yamuna basins (India) with deposition ages ranging from 0 to 26 kyr. Li isotopes fractionate during chemical weathering and could potentially give us some insights on past variations of weathering intensity. We find that Li isotope composition vary between -1.5 and 2 ‰. Before 14 kyr ago, sediments exhibit negative values followed a sharp increase to positive values between 11 and 14 kyr ago. This increase in could be explained by (i) an increase in average temperature, where a higher temperature of equilibration between water and precipitating clays results in higher Li isotope ratios; (ii) a change in mineralogy, as the type and crystallinity of clays will fact the isotopic composition; or (iii) a decrease in chemical weathering intensity, as Li isotope ratios are believed to decrease in sediments/soils with increasing weathering intensity (Rudnick et al., 2004). Interestingly, this period of shift in Li isotope composition also corresponds to an intensification of monsoon rainfall. If the change in Li isotope compositions is the result of a decrease of chemical weathering intensity, this would imply that despite of more intense rainfall, weathering has been less intense during the Holocene. This could be explained as greater rainfall will generate more erosion and sediments are likely to spend less time in the basin, thus the amount of time available for weathering is reduced. This would imply that chemical weathering is mostly controlled by the erosive power of greater rainfall over

  17. Geomagnetic intensity variations for the past 8 kyr: New archaeointensity results from Eastern China

    NASA Astrophysics Data System (ADS)

    Cai, Shuhui; Tauxe, Lisa; Deng, Chenglong; Pan, Yongxin; Jin, Guiyun; Zheng, Jianming; Xie, Fei; Qin, Huafeng; Zhu, Rixiang

    2014-04-01

    In this study, we have carried out paleointensity experiments on 918 specimens spanning the last ∼7 kyr, including pottery fragments, baked clay and slag, collected from Shandong, Liaoning, Zhejiang and Hebei Provinces in China. Approximately half of the specimens yielded results that passed strict data selection criteria and give high-fidelity paleointensities. The virtual axial dipole moments (VADMs) of our sites range from ∼2×1022 to ∼13×1022 Am. At ∼2250 BCE our results suggest a paleointensity low of ∼2×1022 Am, which increases to a high of ∼13×1022 Am by ∼1300 BCE. This rapid (less than 1000 yrs) six-fold change in the paleointensity may have important implications for the dynamics of core flow at this time. Our data from the last ∼3 kyr are generally in good agreement with the ARCH3k.1 model, but deviate significantly at certain time periods from the CALS3k.4 and CALS10k.1b model, which is likely due to differences in the data used to constrain these models. At ages older than ∼3 ka, where only the CALS10k.1b model is available for comparison, our data deviate significantly from the model. Combining our new results with the published data from China and Japan, we provide greatly improved constraints for the regional model of Eastern Asia. When comparing the variations of geomagnetic field in three global representative areas of Eastern Asia, the Middle East and Southern Europe, a common general trend of sinusoidal variations since ∼8 ka is shown, likely dominated by the dipole component. However, significant disparities are revealed as well, which we attribute to non-dipolar components caused by movement of magnetic flux patches at the core-mantle boundary.

  18. Computer-Aided System Engineering and Analysis (CASE/A) Programmer's Manual, Version 5.0

    NASA Technical Reports Server (NTRS)

    Knox, J. C.

    1996-01-01

    The Computer Aided System Engineering and Analysis (CASE/A) Version 5.0 Programmer's Manual provides the programmer and user with information regarding the internal structure of the CASE/A 5.0 software system. CASE/A 5.0 is a trade study tool that provides modeling/simulation capabilities for analyzing environmental control and life support systems and active thermal control systems. CASE/A has been successfully used in studies such as the evaluation of carbon dioxide removal in the space station. CASE/A modeling provides a graphical and command-driven interface for the user. This interface allows the user to construct a model by placing equipment components in a graphical layout of the system hardware, then connect the components via flow streams and define their operating parameters. Once the equipment is placed, the simulation time and other control parameters can be set to run the simulation based on the model constructed. After completion of the simulation, graphical plots or text files can be obtained for evaluation of the simulation results over time. Additionally, users have the capability to control the simulation and extract information at various times in the simulation (e.g., control equipment operating parameters over the simulation time or extract plot data) by using "User Operations (OPS) Code." This OPS code is written in FORTRAN with a canned set of utility subroutines for performing common tasks. CASE/A version 5.0 software runs under the VAX VMS(Trademark) environment. It utilizes the Tektronics 4014(Trademark) graphics display system and the VTIOO(Trademark) text manipulation/display system.

  19. Geomagnetic field variations during the last 400 kyr in the western equatorial Pacific: Paleointensity-inclination correlation revisited

    NASA Astrophysics Data System (ADS)

    Yamazaki, Toshitsugu; Kanamatsu, Toshiya; Mizuno, Sakiko; Hokanishi, Natsumi; Gaffar, Eddy Z.

    2008-10-01

    A paleomagnetic study was conducted on four piston cores newly obtained from the West Caroline Basin in the western equatorial Pacific in order to investigate variations in paleointensity and inclination during the last 400 kyr. An inclination-intensity correlation was previously reported in this region using giant piston cores, but the quality of the paleomagnetic data of the younger end, the last ca. 300 kyr, was needed to be checked because the upper part of the giant piston cores could suffer from perturbation by oversampling. Age control is based on the oxygen-isotope ratios for one core and inter-core correlation using relative paleointensity for other cores. Stacked curves of paleointensity and inclination were constructed from the four cores. It was confirmed that variations on the order of 104 to 105 years occur in inclination as well as paleointensity. A cross-correlation analysis showed that significant in-phase correlation occurs between intensity and inclination for periods longer than about 25 kyr, and power spectra of both paleointensity and inclination variations have peaks at ~100 kyr periods. The regional paleointensity stack with higher resolution than the Sint-800 stack (Guyodo and Valet, 1999) should be useful for paleointensity-assisted chronostratigraphy.

  20. Geomagnetic field variations during the last 400 kyr in the western equatorial Pacific: Paleointensity-inclination correlation revisited

    NASA Astrophysics Data System (ADS)

    Yamazaki, T.; Kanamatsu, T.; Mizuno, S.; Hokanishi, N.; Gaffar, E. Z.

    2008-12-01

    A paleomagnetic study was conducted on four piston cores newly obtained from the West Caroline Basin in the western equatorial Pacific in order to investigate variations in paleointensity and inclination during the last 400 kyr. An inclination-intensity correlation was previously reported in this region using giant piston cores, but the quality of the paleomagnetic data of the younger end, the last ca. 300 kyr, was needed to be checked because the upper part of the giant piston cores could suffer from perturbation by oversampling. Age control is based on the oxygen-isotope ratios for one core and inter-core correlation using relative paleointensity for other cores. The mean inclinations of the four cores show negative inclination anomalies ranging from -5.2 to -11.2 degree. The western equatorial Pacific is documented as a region of a large negative inclination anomalies, and the observed values are comparable to those expected from the time-averaged field (TAF) models [Johnson and Constable, 1997; Hatakeyama and Kono, 2002]. Stacked curves of paleointensity and inclination were constructed from the four cores. It was confirmed that geomagnetic variations on the order of 10 to 100 kyrs occur in inclination as well as paleointensity. A cross-correlation analysis showed that significant in-phase correlation occurs between intensity and inclination for periods longer than about 25 kyr, and power spectra of both paleointensity and inclination variations have peaks at ~100 kyr periods. The regional paleointensity stack with higher resolution than the Sint-800 stack [Guyodo and Valet, 1999] should be useful for paleointensity-assisted chronostratigraphy.

  1. Development and Production of a 201 MHz, 5.0 MW Peak Power Klystron

    SciTech Connect

    Aymar, Galen; Eisen, Edward; Stockwell, Brad; Begum, rasheda; Lenci, Steve; Eisner, Rick; Cesca, Eugene

    2016-01-01

    Communications & Power Industries LLC has designed and manufactured the VKP-8201A, a high peak power, high gain, VHF band klystron. The klystron operates at 201.25 MHz, with 5.0 MW peak output power, 34 kW average output power, and a gain of 36 dB. The klystron is designed to operate between 1.0 MW and 4.5 MW in the linear range of the transfer curve. The klystron utilizes a unique magnetic field which enables the use of a proven electron gun design with a larger electron beam requirement. Experimental and predicted performance data are compared.

  2. Human Exploration of Mars Design Reference Architecture 5.0, Addendum #2

    NASA Technical Reports Server (NTRS)

    Drake, Bret G. (Editor); Watts Kevin D. (Editor)

    2014-01-01

    This report serves as the second Addendum to NASA-SP-2009-566, "Human Exploration of Mars Design Reference Architecture 5.0." The data and descriptions contained within this Addendum capture some of the key assessments and studies produced since publication of the original document, predominately covering those conducted from 2009 through 2012. The assessments and studies described herein are for the most part independent stand-alone contributions. Effort has not been made to assimilate the findings to provide an updated integrated strategy. That is a recognized future effort. This report should not be viewed as constituting a formal plan for the human exploration of Mars.

  3. Power Requirements for The NASA Mars Design Reference Architecture (DRA) 5.0

    NASA Technical Reports Server (NTRS)

    Cataldo, Robert L.

    2009-01-01

    This paper summarizes the power systems analysis results from NASA s recent Mars DRA 5.0 study which examined three architecture options and resulting mission requirements for a human Mars landing mission in the post-2030 timeframe. DRA 5.0 features a long approximately 500 day surface stay split mission using separate cargo and crewed Mars transfer vehicles. Two cargo flights, utilizing minimum energy trajectories, pre-deploy a cargo lander to the surface and a habitat lander into a 24-hour elliptical Mars parking orbit where it remains until the arrival of the crew during the next mission opportunity approximately 26 months later. The pre-deployment of cargo poses unique challenges for set-up and emplacement of surface assets that results in the need for self or robotically deployed designs. Three surface architecture options were evaluated for breadth of science content, extent of exploration range/capability and variations in system concepts and technology. This paper describes the power requirements for the surface operations of the three mission options, power system analyses including discussion of the nuclear fission, solar photovoltaic and radioisotope concepts for main base power and long range mobility.

  4. The U5.0 undulator design for the advanced light source at LBL

    NASA Astrophysics Data System (ADS)

    Hoyer, E.; Chin, J.; Halbach, K.; Hassenzahl, W.; Humphries, D.; Kincaid, B.; Lancaster, H.; Plate, D.; Savoy, R.

    1990-05-01

    The U5.0 undulator, currently under design, is the first in a series of insertion devices planned for the Advanced Light Source at LBL. U5.0 parameters include a 5-cm period and a 5-m length with an 0.837-T maximum field at a 14-mm gap. A hybrid configuration utilizing NdFeB permanent magnet material and vanadium permendur poles is used for the magnetic structure. Construction is modular with many pole assemblies attached to a pole mount, which in turn is fastened onto one of the backing beams. Vertical field integral correction at the ends is accomplished with permanent magnet rotators. The support structure features a four-post configuration, a rigid base with three kinematic floor supports, and two rigid 5-m long backing beams that fit within the 2.4-m-high accelerator enclosure. The drive system is computer-controlled using a stepper motor and shaft encoder coupled to a roller-screw/nut and chain drive train. Vacuum chamber design is a rigid configuration with a 10 mm vertical by 218 mm horizontal aperture of 5.5 m length. Chamber fabrication features a two-piece welded chamber of 5083 H321 aluminum. Pumping is with ion and titanium sublimation pumps.

  5. Visualization of Metabolic Interaction Networks in Microbial Communities Using VisANT 5.0.

    PubMed

    Granger, Brian R; Chang, Yi-Chien; Wang, Yan; DeLisi, Charles; Segrè, Daniel; Hu, Zhenjun

    2016-04-01

    The complexity of metabolic networks in microbial communities poses an unresolved visualization and interpretation challenge. We address this challenge in the newly expanded version of a software tool for the analysis of biological networks, VisANT 5.0. We focus in particular on facilitating the visual exploration of metabolic interaction between microbes in a community, e.g. as predicted by COMETS (Computation of Microbial Ecosystems in Time and Space), a dynamic stoichiometric modeling framework. Using VisANT's unique metagraph implementation, we show how one can use VisANT 5.0 to explore different time-dependent ecosystem-level metabolic networks. In particular, we analyze the metabolic interaction network between two bacteria previously shown to display an obligate cross-feeding interdependency. In addition, we illustrate how a putative minimal gut microbiome community could be represented in our framework, making it possible to highlight interactions across multiple coexisting species. We envisage that the "symbiotic layout" of VisANT can be employed as a general tool for the analysis of metabolism in complex microbial communities as well as heterogeneous human tissues. VisANT is freely available at: http://visant.bu.edu and COMETS at http://comets.bu.edu.

  6. Visualization of metabolic interaction networks in microbial communities using VisANT 5.0

    SciTech Connect

    Granger, Brian R.; Chang, Yi -Chien; Wang, Yan; DeLisi, Charles; Segre, Daniel; Hu, Zhenjun

    2016-04-15

    Here, the complexity of metabolic networks in microbial communities poses an unresolved visualization and interpretation challenge. We address this challenge in the newly expanded version of a software tool for the analysis of biological networks, VisANT 5.0. We focus in particular on facilitating the visual exploration of metabolic interaction between microbes in a community, e.g. as predicted by COMETS (Computation of Microbial Ecosystems in Time and Space), a dynamic stoichiometric modeling framework. Using VisANT's unique meta-graph implementation, we show how one can use VisANT 5.0 to explore different time-dependent ecosystem-level metabolic networks. In particular, we analyze the metabolic interaction network between two bacteria previously shown to display an obligate cross-feeding interdependency. In addition, we illustrate how a putative minimal gut microbiome community could be represented in our framework, making it possible to highlight interactions across multiple coexisting species. We envisage that the "symbiotic layout" of VisANT can be employed as a general tool for the analysis of metabolism in complex microbial communities as well as heterogeneous human tissues.

  7. Visualization of metabolic interaction networks in microbial communities using VisANT 5.0

    DOE PAGES

    Granger, Brian R.; Chang, Yi -Chien; Wang, Yan; ...

    2016-04-15

    Here, the complexity of metabolic networks in microbial communities poses an unresolved visualization and interpretation challenge. We address this challenge in the newly expanded version of a software tool for the analysis of biological networks, VisANT 5.0. We focus in particular on facilitating the visual exploration of metabolic interaction between microbes in a community, e.g. as predicted by COMETS (Computation of Microbial Ecosystems in Time and Space), a dynamic stoichiometric modeling framework. Using VisANT's unique meta-graph implementation, we show how one can use VisANT 5.0 to explore different time-dependent ecosystem-level metabolic networks. In particular, we analyze the metabolic interaction networkmore » between two bacteria previously shown to display an obligate cross-feeding interdependency. In addition, we illustrate how a putative minimal gut microbiome community could be represented in our framework, making it possible to highlight interactions across multiple coexisting species. We envisage that the "symbiotic layout" of VisANT can be employed as a general tool for the analysis of metabolism in complex microbial communities as well as heterogeneous human tissues.« less

  8. Ground motions from the 2002 Au Sable Forks, New York earthquake of M5.0

    NASA Astrophysics Data System (ADS)

    Sonley, E.; Atkinson, G. M.

    2002-12-01

    The moment magnitude (M) 5.0 earthquake that occurred near Au Sable Forks, New York on April 20, 2002 is the first moderate event in eastern North America to be well recorded on modern regional broadband seismographic stations, and is thus important in refining our understanding of source and propagation processes of moderate ENA earthquakes. We analyze the available seismographic recordings to obtain the source spectrum of the Au Sable Forks earthquake, comparing the results obtained using two methods. In the Direct Method, the Fourier spectra of the records from each station are corrected back to the source by using an empirical regional attenuation model for ENA. In the Empirical Green's Function Method, aftershocks are used as empirical Green's Functions to remove path and site effects. Results from these two methods agree closely, and are in agreement with a two-corner source model for ENA. A pronounced sag in the source spectrum at a frequency near 2 Hz is suggestive of significant source complexity. Observed response spectral amplitudes agree well with the predictions of several ground-motion relations for ENA for an event of M 5.0. It is concluded that ground motions from this earthquake were 'typical' for ENA earthquakes of this magnitude.

  9. Biogenic sedimentation beneath the California Current system for the past 30 kyr and its paleoceanographic significance

    USGS Publications Warehouse

    Gardner, J.V.; Dean, W.E.; Dartnell, P.

    1997-01-01

    A north-south transect of 17 cores was constructed along the eastern boundary of the California Current system from 33?? to 42?? N to investigate the changes in biogenic sedimentation over the past 30 kyr. Percentages and mass accumulation rates of CaCO3, Corg, and biogenic opal were assembled at 500 to 1000 years/sample to provide relatively high resolution. Time-space maps reveal a complex pattern of changes that do not follow a simple glacial-interglacial two-mode model. Biogenic sedimentation shows responses that are sometimes time-transgressive and sometimes coeval, and most of the responses show more consistency within a limited geographic area than any temporal consistency. Reconstructed conditions during late oxygen isotope stage 3 were more like early Holocene conditions than any other time during the last 30 kyr. Coastal upwelling and productivity during oxygen isotope stage 3 were relatively strong along the central California margin but were weak along the northern California margin. Precipitation increased during the last glacial interval in the central California region, and the waters of the southern California margin had relatively low productivity. Productivity on the southern Oregon margin was relatively low at the beginning of the last glacial interval, but by about 20 ka, productivity in this area significantly increased. This change suggests that the center of the divergence of the West Wind Drift shifted south at this time. The end of the last glacial interval was characterized by increased productivity in the southern California margin and increased upwelling along the central California margin but upwelling remained weak along the northern California margin. A sudden (<300 years) decrease in CaCO3, Corg, and biogenic opal occurred at 13 ka. The changes suggest a major reorientation of the atmospheric circulation in the North Pacific and western North America and the establishment of a strong seasonality in the central California region. A

  10. AMS Chronology Reveals Ice Sheet Retreat at 15.5 kyr; Provides North Atlantic Chill and Feedbacks for Abrupt Climate Warming

    NASA Astrophysics Data System (ADS)

    Peteet, D. M.; Beh, M.; Orr, C.; Kurdyla, D.; Guilderson, T. P.

    2009-12-01

    The timing of the southeastern Laurentide ice sheet collapse is critical to understanding ocean-atmosphere-ice dynamics. Yet at present an enigma remains based on conflicting evidence including radiocarbon ages on bulk and identifiable macrofossils in lakes, 10Be cosmogenic dating results, and glacial lake varve sequences. Disparate data sources offer conflicting chronologies concerning when ice began retreating from the Laurentide New York - New Jersey -Pennsylvania Last Glacial Maximum (LGM) position. Our study, an investigation of lake basal clays and silts (0.5-8% organic), finds the deglaciation at 15 kyr. These results are 5-8 kyr later than previous deglaciation chronology (23-20 kyr) based upon bulk radiocarbon dating of lake sediments and extrapolation, 8-12 kyr later than varve chronologies, and 4-8kyr later than 10Be results. Our surprising result is generated by 15 accelerator mass spectrometry 14C dates from tundra/spruce macrofossils in 9 basal lake sediments. These dates indicate pioneer plant colonization from areas south and west as the landscape stabilized, just prior to widespread (Bolling) warming which induced rapid limnic organic sedimentation. While warming began as early as 17kyr as evidenced by terrestrial and marine records south of the ice margin, this cold meltwater lid on the N. Atlantic may have delayed the southern margin retreat to 15 kyr, when ice-free soils/lakes provided positive terrestrial/water vapor feedback for the swift pronounced warming.

  11. Environmental changes, climate and anthropogenic impact in south-east Tunisia during the last 8 kyr

    NASA Astrophysics Data System (ADS)

    Jaouadi, Sahbi; Lebreton, Vincent; Bout-Roumazeilles, Viviane; Siani, Giuseppe; Lakhdar, Rached; Boussoffara, Ridha; Dezileau, Laurent; Kallel, Nejib; Mannai-Tayech, Beya; Combourieu-Nebout, Nathalie

    2016-06-01

    Pollen and clay mineralogical analyses of a Holocene sequence from Sebkha Boujmel (southern Tunisia) trace the climatic and environmental dynamics in the lower arid bioclimatic zone over the last 8000 years. During the mid- to late Holocene transition, between ca. 8 and 3 ka BP, a succession of five wet-dry oscillations is recorded. An intense arid event occurs between ca. 5.7 and 4.6 ka BP. This episode marks the onset of a long-term aridification trend with a progressive retreat of Mediterranean woody xerophytic vegetation and of grass steppes. It ends with the establishment of pre-desert ecosystems around 3 ka BP. The millennial-scale climate change recorded in the data from Sebkha Boujmel is consistent with records from the south and east Mediterranean, as well as with climatic records from the desert region for the end of the African Humid Period (AHP). Eight centennial climatic events are recorded at Sebkha Boujmel and these are contemporary with those recorded in the Mediterranean and in the Sahara. They indicate a clear coupling between the southern Mediterranean and the Sahara before 3 ka BP. The event at 4.2 ka BP is not evidenced and the link between events recorded in Sebkha Boujmel and the North Atlantic cooling events is clearer from ca. 3 ka BP onwards. These variations indicate the importance of climatic determinism in the structuring of landscapes, with the establishment of the arid climatic conditions of the late Holocene. It is only from ca. 3 ka BP onwards that the dynamic of plant associations is modified by both human activity and climatic variability. The climatic episodes identified during the historic period indicate strong regionalisation related to the differential impact of the North Atlantic Oscillation (NAO) and the Mediterranean Oscillation (MO) on the Mediterranean Basin. The local human impact on regional ecosystems is recorded in the form of episodes of intensification of pastoral and/or agricultural activities. The development of

  12. Nuclear waste glass product consistency test (PCT), Version 5.0. Revision 2

    SciTech Connect

    Jantzen, C.M.; Bibler, N.E.; Beam, D.C.; Ramsey, W.G.; Waters, B.J.

    1992-06-01

    Liquid high-level nuclear waste will be immobilized at the Savannah River Site (SRS) by vitrification in borosilicate glass. The glass will be produced in the Defense Waste Processing Facility (DWPF), poured into stainless steel canisters, and eventually disposed of in a geologic repository. In order to comply with the Waste Acceptance Preliminary Specifications (WAPS), the durability of the glass needs to be measured during production to assure its long term stability and radionuclide release properties. A durability test, designated the Produce Consistency Test (PCT), was developed for DWPF glass in order to meet the WAPS requirements. The response of the PCT procedure was based on extensive testing with glasses of widely different compositions. The PCT was determined to be very reproducible, to yield reliable results rapidly, and to be easily performed in shielded cell facilities with radioactive samples. Version 5.0 of the PCT procedure is attached.

  13. Ionospheric perturbations associated with two recent major earthquakes (M>5.0)

    NASA Astrophysics Data System (ADS)

    Priyadarshi, S.; Kumar, S.; Singh, A. K.

    2011-10-01

    In this paper, dual-frequency GPS data recorded at Varanasi (geographic latitude 25°16' N, longitude 82°59' E) have been analyzed to study the ionospheric perturbations in total electron content (TEC) due to two recent major earthquakes (M>5.0) whose main shocks occurred on 25 February and 12 March 2010. A monthly median of the TEC and associated inter-quartile range, upper bound and lower bound are utilized as a reference to identify abnormal signals during these two earthquakes. The results show anomalous depletions in the TEC. These pre-earthquake ionospheric anomalies appear within 6 days prior to the earthquakes. We have also analyzed the ELF and VLF spectra observed from the DEMETER micro-satellite above the epicenter of the earthquake to support the ionospheric anomalies prior to the earthquakes. A possible mechanism responsible for the ionospheric anomalies due to earthquakes is also discussed.

  14. Estimating the numerical diapycnal mixing in the GO5.0 ocean model

    NASA Astrophysics Data System (ADS)

    Megann, Alex; Nurser, George

    2014-05-01

    Constant-depth (or "z-coordinate") ocean models such as MOM and NEMO have become the de facto workhorse in climate applications, and have attained a mature stage in their development and are well understood. A generic shortcoming of this model type, however, is a tendency for the advection scheme to produce unphysical numerical diapycnal mixing, which in some cases may exceed the explicitly parameterised mixing based on observed physical processes (e.g. Hofmann and Maqueda, 2006), and this is likely to have effects on the long-timescale evolution of the simulated climate system. Despite this, few quantitative estimations have been made of the typical magnitude of the effective diapycnal diffusivity due to numerical mixing in these models. GO5.0 is the latest ocean model configuration developed jointly by the UK Met Office and the National Oceanography Centre (Megann et al, 2013). It uses version 3.4 of the NEMO model, on the ORCA025 global tripolar grid. Two approaches to quantifying the numerical diapycnal mixing in this model are described: the first is based on the isopycnal watermass analysis of Lee et al (2002), while the second uses a passive tracer to diagnose mixing across density surfaces. Results from these two methods will be compared and contrasted. Hofmann, M. and Maqueda, M. A. M., 2006. Performance of a second-order moments advection scheme in an ocean general circulation model. JGR-Oceans, 111(C5). Lee, M.-M., Coward, A.C., Nurser, A.G., 2002. Spurious diapycnal mixing of deep waters in an eddy-permitting global ocean model. JPO 32, 1522-1535 Megann, A., Storkey, D., Aksenov, Y., Alderson, S., Calvert, D., Graham, T., Hyder, P., Siddorn, J., and Sinha, B., 2013: GO5.0: The joint NERC-Met Office NEMO global ocean model for use in coupled and forced applications, Geosci. Model Dev. Discuss., 6, 5747-5799,.

  15. Coarse fraction fluctuations in pelagic carbonate sediments from the tropical Indian Ocean: A 1500-kyr record of carbonate dissolution

    NASA Astrophysics Data System (ADS)

    Bassinot, Franck C.; Beaufort, Luc; Vincent, Edith; Labeyrie, Laurent D.; Rostek, Frauke; Müller, Peter J.; Quidelleur, Xavier; Lancelot, Yves

    1994-08-01

    Appendix Table Al Is available with entire article onmicrofiche. Order from the American Geophysical Union, 2000Florida Avenue, N.W., Washington, D.C. 20009. DocumentP94-001; $2.50. Payment must accompany order.We examined coarse fraction contents of pelagic carbonates deposited between 2000-and 3700-m water depth in the tropical Indian Ocean using Ocean Drilling Program (ODP) sites 722 (Owen Ridge, Arabian Sea) and 758 (Ninetyeast Ridge, eastern equatorial Indian Ocean), and four giant piston cores collected by the French R/V Marion Dufresne during the SEYMAMA expedition. Over the last 1500 kyr, coarse fraction records display high-amplitude oscillations with an irregular wavelength on the order of ˜500 kyr. These oscillations can be correlated throughout the entire equatorial Indian Ocean, from the Seychelles area eastward to the Ninetyeast Ridge, and into the Arabian Sea. Changes in grain size mainly result from changes in carbonate dissolution as evidenced by the positive relationship between coarse fraction content and a foraminiferal preservation index based on test fragmentation. The well-known "mid-Bruhes dissolution cycle"represents the last part of this irregular long-term dissolution oscillation. The origin of this long-term oscillation is still poorly understood. Our observations suggest that it is not a true cycle (it has an irregular wavelength) and we propose that it may result from long-term changes in Ca++flux to the ocean. Sites 722 and 758 δ18O records provide a high-resolution stratigraphy that allows a detailed intersite comparison of the two coarse fraction records over the last 1500 kyr. Site 722 (2030 m) lies above the present and late Pleistocene lysocline. The lysocline shoaled to the position of site 758 (2925 m) only during the interglacial intervals that occurred between about 300 and 500 ka (Peterson and Prell, 1985a). Despite these supralysoclinal positions of the two sites, short-term changes in coarse fraction contents are

  16. Time evolution of the mineralogical composition of Mississippi Valley loess over the last 10 kyr: Climate and geochemical modeling

    NASA Astrophysics Data System (ADS)

    Goddéris, Yves; Williams, Jennifer Z.; Schott, Jacques; Pollard, Dave; Brantley, Susan L.

    2010-11-01

    Anthropogenic and natural climate change affect processes in the atmosphere, biosphere, hydrosphere, and pedosphere. The impact of climate on soil evolution has not been well-explored, largely due to slow rates and the complexity of coupled processes that must be observed and simulated. The rates of mineral weathering in loess deposited 23 kyr ago and experiencing soil formation for 13 kyr are explored here using the WITCH model for weathering and the GENESIS model for climate simulation. The WITCH model, which uses rigorous kinetic parameters and laws with provision for the effect on rates of deviation from equilibrium, can successfully simulate the depletion profiles in the soil for dolomite and albite if soil CO 2 is assumed to rise over the last 10 kyr up to about 30-40× the present atmospheric pressure, and if the solubility product of the Ca-smectite is assumed equal to that of an Fe(III)-rich Ca-montmorillonite. Such simulations document that dissolution behavior for silicates and carbonates are strongly coupled through pH, and for Ca-smectite and feldspars through dissolved silica. Such coupling is not incorporated in simple geometric and analytical models describing mineral dissolution, and therefore probably contributes to the long-standing observation of discrepancies among laboratory and field mineral dissolution rates.

  17. Progress in the reconstruction of Quaternary climate dynamics in the Northwest Pacific: A new modern analogue reference dataset and its application to the 430-kyr pollen record from Lake Biwa

    NASA Astrophysics Data System (ADS)

    Tarasov, Pavel E.; Nakagawa, Takeshi; Demske, Dieter; Österle, Hermann; Igarashi, Yaeko; Kitagawa, Junko; Mokhova, Lyudmila; Bazarova, Valentina; Okuda, Masaaki; Gotanda, Katsuya; Miyoshi, Norio; Fujiki, Toshiyuki; Takemura, Keiji; Yonenobu, Hitoshi; Fleck, Andreas

    2011-09-01

    This study presents a newly compiled dataset of modern pollen and climate data from 798 sites across Japan and the Russian Far East. This comprehensive reference dataset combined with the modern analogue technique (MAT) provides a powerful tool for pollen-based reconstruction of the Quaternary Northwest Pacific climate. Pollen-derived reconstruction of the modern climate at the reference pollen-sampling sites matches well with the estimated modern climate values ( R2 values vary between 0.79 and 0.95, and RMSEP values vary between 5.8 and 9.7% of the modern climatic range for all nine tested variables). The successful testing of the method encourages its application to the fossil pollen records. We used a coarse-resolution pollen record from Lake Biwa to reconstruct glacial-interglacial climate dynamics in central Japan since ~ 438 kyr and compared it to the earlier reconstruction based on a less representative reference dataset. The current and earlier results consistently demonstrate that the coldest glacial intervals experienced pronounced cooling in winter and moderate cooling in summer, supporting the growth of cool mixed forest (COMX) where warm mixed forest (WAMX) predominates today. During the last glacial, maximum (~ 24 kyr BP) mean temperatures of the coldest (MTCO) and warmest (MTWA) month were about - 13 °C (RMSEP = 2.34 °C) and 21 °C (RMSEP = 1.66 °C) respectively, and annual precipitation (PANN) was about 800 mm (RMSEP = 158.06 mm). During the thermal optimums of the interglacial intervals, the temperatures of the coldest and warmest month were above 0 °C and 25 °C respectively, leading to the reconstruction of WAMX and temperate conifer forest (TECO). Although both these vegetation types grow in the southern part of Japan today, WAMX requires warmer space. The presence of WAMX during marine isotope stages (MIS) 11 and 1, and its absence during MIS 9 and MIS 5 contradict the marine isotope and Antarctic ice records, suggesting that the latter

  18. Systems analysis programs for hands-on integrated reliability evaluations (SAPHIRE), Version 5.0

    SciTech Connect

    Russell, K.D.; Kvarfordt, K.J.; Hoffman, C.L.

    1995-10-01

    The Systems Analysis Programs for Hands-on Integrated Reliability Evaluations (SAPHIRE) refers to a set of several microcomputer programs that were developed to create and analyze probabilistic risk assessments (PRAs), primarily for nuclear power plants. The Graphical Evaluation Module (GEM) is a special application tool designed for evaluation of operational occurrences using the Accident Sequence Precursor (ASP) program methods. GEM provides the capability for an analyst to quickly and easily perform conditional core damage probability (CCDP) calculations. The analyst can then use the CCDP calculations to determine if the occurrence of an initiating event or a condition adversely impacts safety. It uses models and data developed in the SAPHIRE specially for the ASP program. GEM requires more data than that normally provided in SAPHIRE and will not perform properly with other models or data bases. This is the first release of GEM and the developers of GEM welcome user comments and feedback that will generate ideas for improvements to future versions. GEM is designated as version 5.0 to track GEM codes along with the other SAPHIRE codes as the GEM relies on the same, shared database structure.

  19. Sequence microheterogeneity of parvalbumin pI 5.0 of pike: a mass spectrometric study.

    PubMed

    Permyakov, Sergei E; Karnoup, Anton S; Bakunts, Anush G; Permyakov, Eugene A

    2009-01-01

    Parvalbumin (PA) is a muscle and neuronal calcium-binding protein, the major fish and frog allergen. Its characteristic feature is the presence of multiple isoforms with significantly different amino acid sequences. Here we show that the major isoform of northern pike muscle PA (pI 5.0, alpha-PA) exhibits microheterogeneity of amino acid sequence. ESI Q-TOF mass-spectrometry (MS) analysis of alpha-PA sample showed the presence of two components with mass difference of 71 Da. Analysis of tryptic and endoproteinase Asp-N digests of alpha-PA by MALDI-TOF MS revealed peptides, corresponding to two different amino acid sequences. The sequence differences between variant proteins are limited to AB-domain and include substitutions K27A and L31K, and an extra Leu residue between K11 and K12. Since the affected residues comprise a cluster on the surface of PA, an involvement of the identified region into target recognition is suggested. The substitutions at positions 27 and 31 are located in the region of previously identified epitopes of parvalbumin relevant for PA-specific IgE and IgG binding, which suggests different immunoactivities of the variants. The found microheterogeneity of PA is suggested to be of importance for physiological adaptation of the propulsive musculature to developmental and/or environmental requirements and may contribute to PA allergenicity.

  20. Wide Field Camera 3 Instrument Handbook for Cycle 21 v. 5.0

    NASA Astrophysics Data System (ADS)

    Dressel, L.

    2012-12-01

    The Wide Field Camera 3 (WFC3) is a fourth-generation imaging instrument. It was installed in the Hubble Space Telescope (HST) during Servicing Mission 4 (SM4) in May 2009. WFC3 saw first light on June 24, 2009, following the cooling of its detectors. Servicing Mission 4 Observatory Verification (SMOV) activities were completed in late August 2009, and were followed by the Cycle 17 calibration and science programs. This WFC3 Instrument Handbook has been prepared by the WFC3 team at STScI. It is the basic technical reference manual for WFC3 observers. The information in this Handbook is intended to be useful for Cycle 21 Phase I proposers, for the subsequently selected General Observers (GOs) as they prepare their Phase II specifications, and for those analyzing WFC3 data. The HST Primer and the HST Call for Proposals also contain valuable information for proposers, and the Call for Proposals is the final authority on HST policy. This edition of the WFC3 Instrument Handbook (Version 5.0) was written near the end of the execution of the Cycle 19 calibration plan. It supersedes Version 4.0, and includes results from analysis of the first three cycles of on-orbit performance.

  1. INTERLINE 5. 0 -- An expanded railroad routing model: Program description, methodology, and revised user's manual

    SciTech Connect

    Johnson, P.E.; Joy, D.S. ); Clarke, D.B.; Jacobi, J.M. . Transportation Center)

    1993-03-01

    A rail routine model, INTERLINE, has been developed at the Oak Ridge National Laboratory to investigate potential routes for transporting radioactive materials. In Version 5.0, the INTERLINE routing algorithms have been enhanced to include the ability to predict alternative routes, barge routes, and population statistics for any route. The INTERLINE railroad network is essentially a computerized rail atlas describing the US railroad system. All rail lines, with the exception of industrial spurs, are included in the network. Inland waterways and deep water routes along with their interchange points with the US railroadsystem are also included. The network contains over 15,000 rail and barge segments (links) and over 13,000 stations, interchange points, ports, and other locations (nodes). The INTERLINE model has been converted to operate on an IBM-compatible personal computer. At least a 286 computer with a hard disk containing approximately 6 MB of free space is recommended. Enhanced program performance will be obtained by using arandom-access memory drive on a 386 or 486 computer.

  2. Indian Ocean sea surface temperatures and vegetation change in SE African tropics during the past 800 Kyr

    NASA Astrophysics Data System (ADS)

    Castaneda, I. S.; Caley, T.; Dupont, L. M.; Kim, J.; Sinninghe Damsté, J. S.; Malaize, B.; Caillon, N.; Giraudeau, J.; Schouten, S.

    2011-12-01

    Presently, few vegetation records exist for the region of SE Africa that span multiple glacial-interglacial cycles yet such records can provide important insights into past continental climatic variability. Here, we examine vegetation and SST change in SE Africa from a ~800 Kyr sediment core (MD96-2048) collected from the continental shelf near the Limpopo River, which drains Botswana, southern Mozambique and northern South Africa. The coring site is located at 26°S and is likely situated outside of the influence of the Intertropical Convergence Zone (ITCZ). We find that plant leaf wax (n-alkane) carbon isotope (δ13C) and pollen records are in good agreement and exhibit pronounced glacial-interglacial variability. Relatively enriched n-alkane δ13C values are noted during glacial periods and reflect increased inputs of C4 vegetation, coincident with higher percentages of Poaceae (grass) pollen and cooler SST. Conversely, during interglacials, relatively depleted n-alkane δ13C values are noted and coincide with higher percentages of woodland and forest pollen and warmer SST. Previous studies of this core demonstrated that SST and salinity records based on both inorganic (δ18O and Mg/Ca) and organic (Uk'37 and TEX86) geochemical proxies display strong obliquity-driven 41-Kyr cycles, that are nearly in phase with annual mean insolation and air temperature at the high southern latitudes (Caley et al., 2011). Likewise, the n-alkane δ13C record was found to contain a strong 41-Kyr obliquity cycle. Interestingly, a strong 23-Kyr precession cycle is also present in the n-alkane δ13C record, that is nearly in phase with precession minima. Our results therefore suggest that vegetation change in this region reflects the dual influence of both southern and northern high-latitude climate forcings. In contrast to the Lake Malawi (East Africa) pollen record, which indicates a treeless landscape and extreme aridity from 105-90-Kyr (Beuning et al., 2011), the pollen record of

  3. Variations in sea surface hydrology in the southern Makassar Strait over the past 26 kyr

    NASA Astrophysics Data System (ADS)

    Schröder, Jan F.; Holbourn, Ann; Kuhnt, Wolfgang; Küssner, Kevin

    2016-12-01

    We present centennial-scale records of sea surface temperature and oxygen isotopes in a sediment core from Mandar Bay, offshore Sulawesi in the southern Makassar Strait, which provide new insights into the variability of Indonesian climate over the past 26 kyr. The age model for the core is constrained by 17 AMS radiocarbon ages, with a surface ocean reservoir age correction based on paired wood and foraminiferal samples. Small Holocene reservoir ages of 105 ± 180 years point to intense surface ocean-atmosphere interchange linked to increased monsoonal precipitation, whereas Last Glacial Maximum and deglacial reservoir ages are significantly higher. Mg/Ca derived sea surface temperature reconstructions based on Globigerinoides ruber (s. s., white) exhibit an extended plateau during the Antarctic Cold Reversal, suggesting an atmospheric connection to high-latitude Southern Hemisphere climate and a seasonal bias on G. ruber. This is in agreement with southern hemisphere sites along the track of the Indonesian Throughflow and in contrast to Northern Hemisphere records from the South China Sea, Sulu Sea and Western Pacific (off Mindanao), which exhibit warming during the Bølling-Allerød. Ice-volume corrected δ18O seawater (δ18Osw) increased during Heinrich Stadial 1 and the Younger Dryas, whereas the Bølling-Allerød is characterized by low δ18Osw. We attribute δ18Osw variability in the southern Makassar Strait during the Last Glacial Maximum and glacial termination to changes in provenance and seasonality of precipitation rather than to variability in the amount of local precipitation and runoff.

  4. Design for a modular nonvolatile 5.0+ Gb/sec solid state data recorder

    NASA Astrophysics Data System (ADS)

    Wise, Richard J., Jr.; Jacobs, Richard W.

    2000-11-01

    The paper presents a design for a High-Density Solid-State Data Recorder (HDR), commercially known as the Tornado 2HD, for use in Reconaissance and High-Speed Sensor Data Acquisition applications. The HDR has the capacity to record data in excess of 5.0Gb/sec sustained via a proprietary Low-Voltage Differential Serial (LVDS) interface and employs an open-architecture VMEbus front end. Allowing data input and archiving through a myriad of standard PMC (PCI Mezznine Card)-based interfaces (SCSI, Fiber-Channel, USB, etc.). A dedicated DCRSi240 interface is also included to allow archiving of data to compatible tape recorders. Solid-state memory is composed of 512Mb EEPROMs arranged as a Removable Memory Unit (RMU) modules of eight memory cards, with each card providing 13.82GB of data storage, for a total of 110.2GB per module. Memory is expandable in .3GB blocks and is theoretically limited only by space and total power requirements of the recorder, since all data and control signals are synchronously redriven between memory cards and RMUs. Erase, read, and write operations for each memory card are controlled autonomously by a single Matrix Array Controller (MAC) FPGA mounted on the card. Recorder user interface is provided by a VME-based dual PowerPC Single-Board Computer (SBC) with control provided via RS-232, DCRSi240, or Ethernet interfaces. The VME front end also provides standard capabilities, such as IRIG-B, Digital I/O, SCSI, and other PMC-based interfaces.

  5. FERMI/GLAST Integrated Trending and Plotting System Release 5.0

    NASA Technical Reports Server (NTRS)

    Ritter, Sheila; Brumer, Haim; Reitan, Denise

    2012-01-01

    An Integrated Trending and Plotting System (ITPS) is a trending, analysis, and plotting system used by space missions to determine performance and status of spacecraft and its instruments. ITPS supports several NASA mission operational control centers providing engineers, ground controllers, and scientists with access to the entire spacecraft telemetry data archive for the life of the mission, and includes a secure Web component for remote access. FERMI/GLAST ITPS Release 5.0 features include the option to display dates (yyyy/ddd) instead of orbit numbers along orbital Long-Term Trend (LTT) plot axis, the ability to save statistics from daily production plots as image files, and removal of redundant edit/create Input Definition File (IDF) screens. Other features are a fix to address invalid packet lengths, a change in naming convention of image files in order to use in script, the ability to save all ITPS plot images (from Windows or the Web) as GIF or PNG format, the ability to specify ymin and ymax on plots where previously only the desired range could be specified, Web interface capability to plot IDFs that contain out-oforder page and plot numbers, and a fix to change all default file names to show yyyydddhhmmss time stamps instead of hhmmssdddyyyy. A Web interface capability sorts files based on modification date (with newest one at top), and the statistics block can be displayed via a Web interface. Via the Web, users can graphically view the volume of telemetry data from each day contained in the ITPS archive in the Web digest. The ITPS could be also used in nonspace fields that need to plot data or trend data, including financial and banking systems, aviation and transportation systems, healthcare and educational systems, sales and marketing, and housing and construction.

  6. The U5.0 Undulator for the Advanced Light Source

    NASA Astrophysics Data System (ADS)

    Hoyer, E.; Chin, J.; Halbach, K.; Hassenzahl, W. V.; Humphries, D.; Kincaid, B.; Lancaster, H.; Plate, D.

    1992-01-01

    The U5.0 Undulator, an 89 period, 5 cm period length, 4.6 m long insertion device has been designed, is being fabricated, and is scheduled for completion in early 1992. This undulator will be the first high brightness source, in the 50 to 1,500 eV range, for the Advanced Light Source at the Lawrence Berkeley Laboratory. A hybrid magnetic configuration using Nd-Fe-B permanent magnet material and vanadium permendur poles has been selected to achieve the field quality needed to meet performance requirements. The magnetic structure is modular with each half consisting of five assembly sections, which provide the periodic structure, and end structures, for entrance and exit correction, mounted on a steel backing beam. Each assembly section consists of 35 half-period pole assemblies bolted to a mount. The required 0.837 T effective peak field at a 1.4 cm gap has been verified with model measurements. Vertical field integral correction is accomplished with the end structures, each having an arrangement of permanent magnet rotors which will be adjusted to minimize electron beam missteering over the undulator operating field range. To reduce the effect of environmental fields, the steel backing beams are connected through parallel, low-reluctance, Ni-Fe hinges. The magnetic structure is connected through four rollernuts to the drive system that provides gap adjustment with an arrangement of roller screws, chain drives, a gear reduction unit, and a stepper motor driven by a closed loop control system. Magnetic structure and drive system support are from a 2.4 m high structure which includes a support base with four vertical supports. The vacuum chamber design is a two-piece machined and welded 5083-H321 aluminum construction of 5.1 m length. Pumping is with a combination of ion, titanium sublimation pump and nonevaporable getter pumps. Magnetic design, subsystem design, and fabrication progress are presented.

  7. A Compact X-ray Source in the Radio PWN G141.2+5.0

    NASA Astrophysics Data System (ADS)

    Reynolds, Stephen P.; Borkowski, Kazimierz J.

    2015-08-01

    We report the results of a 50 ks Chandra observation of the recently discovered radio object G141.2+5.0, presumed to be a pulsar-wind nebula (PWN) (Kothes et al. 2014). We find a faint unresolved X-ray source coincident with the central peak of radio emission. Spectral fits to the 241 counts show that an absorbed power-law describes the data well, with absorbing column NH = 4.8 (2.6, 7.3) x 1021 cm-2 and photon index Γ = 1.6 (1.2, 2.1). (A black-body fit is slightly less favored statistically, and has an implausibly high temperature, kT = 0.9 keV.) For a distance of 4 kpc, the unabsorbed luminosity between 0.5 and 8 keV is 1.8 (1.1, 3.0) x 1032 erg s-1. No extended emission is seen; a very conservative upper limit to Lx (nebula) is about the same luminosity as that observed from the point source. The radio luminosity is about 3 x 1030 erg s-1 the X-ray upper limit then gives Lx/Lr < 700, satisfied by almost all pulsar-wind nebulae. Both Lx and Γ are quite typical of pulsars in PWNe. The steep radio spectrum (α ~ -0.7), if continued to the X-ray without a break, predicts Lx (nebula) ~ 1 x 1033 erg s-1, so additional spectral steepening between radio and X-rays is required, as is true of all known PWNe. The high Galactic latitude gives a z-distance of 350 pc above the Galactic plane, quite unusual for a Population I object.

  8. Quasiparticle energies for cubic BN, BP, and BAs

    SciTech Connect

    Surh, M.P.; Louie, S.G.; Cohen, M.L. Materials Sciences Division, Lawrence Berkeley Laboratory, Berkeley, California 94720)

    1991-04-15

    Electronic excitation energies at the high-symmetry points {Gamma}, {ital X}, and {ital L} are obtained for zinc-blende-structure BN, BP, and BAs in the {ital GW} approximation using a model dielectric function. A model for the static screening matrix makes use of the {ital ab} {ital initio} ground-state charge density and either experimental values or empirical estimates for {epsilon}{sub {infinity}}, the electronic contribution to the macroscopic dielectric constant. Wave functions from an {ital ab} {ital initio} local-density-approximation calculation with norm-conserving pseudopotentials are employed along with the self-consistent quasiparticle spectrum to obtain the energy-dependent one-particle Green function {ital G}. The minimum band gaps are found to be 6.3, 1.9, and 1.6 eV for BN, BP, and BAs, respectively, in close agreement with existing measurements of 6.1 and 2.0 eV for BN and BP, respectively. The BN direct band gap is predicted to be 11.4 eV versus the experimental value of 14.5 eV, and the BP direct band gap is predicted to be 4.4 eV versus 5.0 eV from experiment.

  9. Radio perspectives on the Monoceros SNR G205.5+0.5

    NASA Astrophysics Data System (ADS)

    Xiao, L.; Zhu, M.

    2012-09-01

    Context. The Monoceros supernova remnant (SNR G205.5+0.5) is a large shell-type SNR located in the Rosette molecular complex and thought to be interacting with the Rosette Nebula. Aims: We aim to re-examine the radio spectral index and its spatial variation over the Monoceros SNR as well as study its properties of evolution within the complex interstellar medium. Methods: We extracted radio continuum data for the Monoceros complex region from the Effelsberg 21 cm and 11 cm surveys and the Urumqi 6 cm polarization survey. We used the new Arecibo GALFA-HI survey data with much higher resolution and sensitivity than that previously available to identify the HI shell related with the SNR. Multi-wavelengths data are included to investigate the properties of the SNR. Results: The spectral index α (Sν ∝ να) averaged over the SNR is -0.41 ± 0.16. The TT-plots and the distribution of α over the SNR show spatial variations that steepen toward the inner western filamentary shell. Polarized emission is prominent on the western filamentary shell region. The RM there is estimated to be about 30 ± 77n rad m-2, where the n = 1 solution is preferred, and the magnetic field has a strength of about 9.5 μG. From the HI channel maps, further evidence is provided for an interaction between the Monoceros SNR and the Rosette Nebula. We identify partial neutral hydrogen shell structures in the northwestern region at velocities of +15 km s-1 circumscribing the continuum emission. The HI shell has swept up a mass of about 4000 M⊙ for a distance of 1.6 kpc. The western HI shell, well associated with the dust emission, is found to lie outside of the radio shell. We suggest that the Monoceros SNR is evolving within a cavity blown out by the progenitor and has triggered part of the star formation in the Rosette Nebula. Conclusions: The Monoceros SNR is interacting with the ambient interstellar medium with ultra-high energy emission detected. Its interaction with the Rosette Nebula is

  10. Magnetic and Geochemical Records of Glacial Terminations, Weathering and Carbon Burial in the Southeastern South China Sea for the Last 800 kyr

    NASA Astrophysics Data System (ADS)

    Kandasamy, S.; Kao, S.; Hsu, S.; Lee, T.; Velasco, V. M.; Soon, W.; Chen, M.

    2013-12-01

    Rebuilding of past climate and oceanographic records from monsoon dominated Asia is of vital importance for understanding the causes and mechanisms of global and regional climate changes at orbital-millennial timescales. South China Sea (SCS) provides the best marine platform to investigate a number of paleoclimate and paleoceanographic problems on different timescales mainly because of high sedimentation rates, good preservation of microfossils and the location of SCS as a connector between the Western Pacific Warm Pool and the SE Asian monsoon. Here we investigate magnetic, geochemical and isotopic records from a piston core MD97-2142 rose from the southeastern SCS to understand the past glacial terminations, chemical weathering and carbon burial on orbital to millennial timescales for the last 800 kyr. Terrigenous content and Al/Ti ratio reveal higher terrigenous input during glacial periods and vice versa during interglacials. Proxies of chemical weathering reveal larger fluctuations between 150 and 500 kyr than that of the last 150 kyr. Records of C/N ratio and carbon isotope of total organic carbon (δ13CTOC) mimic each other with higher marine productivity during marine isotope stages (MIS) 8, 10 and 12. Enrichment factors of Mn and Mo (EF Mn and EF Mo) show roughly an opposite pattern with <1 EF Mo almost throughout the last 500 kyr may suggest that the southeastern part of SCS has never been attained anoxic condition both glacial and interglacial intervals from MIS 1 through MIS 13. EF Mn shows >1 in most odd MIS, whereas <~1 EF Mn was evident in even MIS, suggesting that the former condition was likely attributed to bottom water ventilation associated with high sea levels during interglacials. We found through two endmember mixing model of δ13CTOC that lower burial of terrigenous fraction of TOC (OCTERR) during glacial intervals (MIS 6, 8, 10 and 12), but vice versa during interglacial (MIS 7, 9 and 11) periods. Our bulk magnetic susceptibility (MS) time

  11. Indonesian Throughflow dynamics of the last 25 kyr: New Uranium Series results from the Indonesian Seas

    NASA Astrophysics Data System (ADS)

    Muller, J.; McManus, J.; Opdyke, B.

    2007-12-01

    In the modern ocean the Indonesian Throughflow (ITF) is a key component of thermohaline circulation (THC) that transports large amounts of heat from the Pacific to the Indian Ocean and is the only tropical connection between major ocean basins. This oceanographic system is known to influence a number of climatic conditions, one significant example being El Niño Southern Oscillation (ENSO). Undoubtedly, the Indonesian seas are important for climate, yet we have only a modest understanding of how this region operated in the past. During the Last Glacial Maximum (LGM) the Indonesian Seas experienced significant sea level regression with consequent changes in boundary conditions (De Deckker et al., 2002). Previous paleo-studies within the Indonesian Seas implied a weakening of the ITF during the LGM (Müller and Opdyke, 2000; Gingele et al., 2001). These interpretations focus on paleoproductivity and sedimentology proxies rather than proxies that more directly measure paleocirculation. In addition, previous interpretations of paleoproductivity may require clarification due to possible post depositional sediment focusing in this region. We present two down core records from the Timor (MD-982167) and Flores Seas (VM33-80) that span back ~25 kyr. We use 231Pa/230Th as a more direct paleocirculation tracer and apply 230Th normalized fluxes and biogenic opal in order to look at paleoproductivity during the LGM, through the deglaciation and into the Holocene. These records extend on current paleooceanographic knowledge from the equatorial realm of the climate system. More specifically the records aim to better understand an important segment of the THC, namely the ITF, and how its strength has interacted with climates of the past. De Deckker P., Tapper N. J., and van der Kaars S. (2002) The status of the Indo-Pacific Warm Pool and adjacent land at the Last Glacial Maximum Global and Planetary Change 35, 25-35. Gingele F. X., De Deckker P., and Hillenbrand C. D. (2001) Clay

  12. Long-Term Probabilistic Forecast for M ≥ 5.0 Earthquakes in Iran

    NASA Astrophysics Data System (ADS)

    Talebi, Mohammad; Zare, Mehdi; Peresan, Antonella; Ansari, Anooshiravan

    2017-03-01

    In this study, a long-term forecasting model is proposed to evaluate the probabilities of forthcoming M ≥ 5.0 earthquakes on a 0.2° grid for an area including the Iranian plateau. The model is built basically from smoothing the locations of preceding events, assuming a spatially heterogeneous and temporally homogeneous Poisson point process for seismicity. In order to calculate the expectations, the space distribution, from adaptively smoothed seismicity, has been scaled in time and magnitude by average number of events over a 5-year forecasting horizon and a tapered magnitude distribution, respectively. The model has been adjusted and applied considering two earthquake datasets: a regional unified catalog (MB14) and a global catalog (ISC). Only the events with M ≥ 4.5 have been retained from the datasets, based on preliminary completeness data analysis. A set of experiments has been carried out, testing different options in the model application, and the average probability gains for target earthquakes have been estimated. By optimizing the model parameters, which leads to increase of the predictive power of the model, it is shown that a declustered catalog has an advantage over a non-declustered one, and a low-magnitude threshold of a learning catalog can be preferred to a larger one. In order to examine the significance of the model results at 95% confidence level, a set of retrospective tests, namely, the L test, the N test, the R test, and the error diagram test, has been performed considering 13 target time windows. The error diagram test shows that the forecast results, obtained for both the two input catalogs, mostly fall outside the 5% critical region that is related to results from a random guess. The L test and the N test could not reject the model for most of the time intervals (i.e. 85 and 62% of times for the ISC and MB14 forecasts, respectively). Furthermore, after backwards extending the time span of the learning catalogs and repeating the L

  13. An 800-kyr Record of Global Surface Ocean δ18Osw and Implications for Ice Volume-Temperature Coupling

    NASA Astrophysics Data System (ADS)

    Shakun, J. D.; Lea, D. W.; Lisiecki, L. E.; Raymo, M. E.

    2014-12-01

    We use 49 paired sea surface temperature (SST)-planktonic δ18O records to extract the mean δ18O of surface ocean seawater (δ18Osw) over the past 800 kyr, which we interpret to dominantly reflect global ice volume, and compare it to SST variability on the same stratigraphy. This analysis suggests that ice volume and temperature contribute to the marine isotope record in ~60/40 proportions, but they show consistently different patterns over glacial cycles. Global temperature cools early during each cycle while major ice sheet growth occurs later, suggesting that ice volume may have exhibited a threshold response to cooling and also had relatively little feedback on it. Multivariate regression analysis suggests that the rate of ice volume change through time is largely determined by the combined influence of orbital forcing, global temperature, and ice volume itself (r2 = 0.70 at zero-lag for 0-400 ka), with sea level rising faster with stronger insolation and warmer temperatures and when there is more ice available to melt. Indeed, cross-spectral analysis indicates that ice volume exhibits a smaller phase lag and larger gain relative to SST at the 41 and 23 kyr periods than at the 100 kyr period, consistent with additional forcing from insolation at the obliquity and precession time scales. Removing the surface ocean δ18Osw signal from the global benthic δ18O stack produces a reconstruction of deep ocean temperature that bears considerable similarity to the Antarctic ice core temperature record (r2 = 0.80 for 0-400 ka), including cooler interglacials before 400 ka. Overall, we find a close association between global surface temperature, deep ocean temperature, and atmospheric CO2. Additionally, we find that rapid cooling precedes the gradual buildup of large continental ice sheets, which may then be instrumental in terminating the cycle.

  14. Volcanic synchronization of Dome Fuji and Dome C Antarctic deep ice cores over the past 216 kyr

    NASA Astrophysics Data System (ADS)

    Fujita, S.; Parrenin, F.; Severi, M.; Motoyama, H.; Wolff, E. W.

    2015-10-01

    Two deep ice cores, Dome Fuji (DF) and EPICA Dome C (EDC), drilled at remote dome summits in Antarctica, were volcanically synchronized to improve our understanding of their chronologies. Within the past 216 kyr, 1401 volcanic tie points have been identified. DFO2006 is the chronology for the DF core that strictly follows O2 / N2 age constraints with interpolation using an ice flow model. AICC2012 is the chronology for five cores, including the EDC core, and is characterized by glaciological approaches combining ice flow modelling with various age markers. A precise comparison between the two chronologies was performed. The age differences between them are within 2 kyr, except at Marine Isotope Stage (MIS) 5. DFO2006 gives ages older than AICC2012, with peak values of 4.5 and 3.1 kyr at MIS 5d and MIS 5b, respectively. Accordingly, the ratios of duration (AICC2012 / DFO2006) range between 1.4 at MIS 5e and 0.7 at MIS 5a. When making a comparison with accurately dated speleothem records, the age of DFO2006 agrees well at MIS 5d, while the age of AICC2012 agrees well at MIS 5b, supporting their accuracy at these stages. In addition, we found that glaciological approaches tend to give chronologies with younger ages and with longer durations than age markers suggest at MIS 5d-6. Therefore, we hypothesize that the causes of the DFO2006-AICC2012 age differences at MIS 5 are (i) overestimation in surface mass balance at around MIS 5d-6 in the glaciological approach and (ii) an error in one of the O2 / N2 age constraints by ~ 3 kyr at MIS 5b. Overall, we improved our knowledge of the timing and duration of climatic stages at MIS 5. This new understanding will be incorporated into the production of the next common age scale. Additionally, we found that the deuterium signals of ice, δDice, at DF tends to lead the one at EDC, with the DF lead being more pronounced during cold periods. The lead of DF is by +710 years (maximum) at MIS 5d, -230 years (minimum) at MIS 7a and +60

  15. Arctic Ocean Paleoenvironmental Change in the last 50 kyr Reconstructed from an Alpha Ridge to Gakkel Ridge Transect

    NASA Astrophysics Data System (ADS)

    Spielhagen, R. F.; Glogowski, S.; Noergaard-Pedersen, N.; Schmidt, A.

    2011-12-01

    The Arctic Ocean has undergone profound changes in the last ca. 50 kyr, reaching from a dense sea ice cover with large numbers of icebergs during the mid-Weichselian glaciation (MWG, >45 ka) to a perennial sea ice cover with seasonally open leads in the Holocene. During the main glacial phases (MWG and last glacial maximum (ca. 20 ka)), large parts of the surrounding continents were covered by ice sheets which discharged icebergs to the ocean, leaving traces in the form of ice-rafted debris (IRD) in the bottom sediments. Different lithologies in the source areas of the icebergs allow to reconstruct the pathways of the ice and thus the large-scale drift pattern of the oceanic ice cover. Microfossils and geochemical proxies give evidence of other parameters of the surface-near water masses and their spatial and temporal variability. In our presentation we will use a multiproxy data set from sediment cores obtained between the Alpha (130-160°W) and Gakkel (30-60°E) ridges to reconstruct the paleoenvironment in the central Arctic with emphasis on the intervals with extensive continental glaciations. Sedimentation rates were generally low (1 cm/kyr or less) with the exception of the MWG with several cm/kyr. Coarse fraction content (IRD and microfossils) in sediments from both glaciation intervals is increasing towards the Alpha Ridge, revealing a stronger influence (iceberg discharge) of the North American Arctic ice sheet if compared to the northern Eurasian ice sheet. Planktic foraminifer occurrences in Alpha Ridge sediments from the MWG indicate that seasonally open waters were present occasionally and may have allowed higher melt rates than in the Eurasian subbasin. The paleoenvironmantal picture for the LGM is more ambiguous because of extremely low sedimentation rates or even an interval of non-sedimentation. However, it seems likely that the eastern part of the Eurasian Basin was largely free of icebergs for a few thousand years during the LGM. The different

  16. CoPub update: CoPub 5.0 a text mining system to answer biological questions.

    PubMed

    Fleuren, Wilco W M; Verhoeven, Stefan; Frijters, Raoul; Heupers, Bart; Polman, Jan; van Schaik, René; de Vlieg, Jacob; Alkema, Wynand

    2011-07-01

    In this article, we present CoPub 5.0, a publicly available text mining system, which uses Medline abstracts to calculate robust statistics for keyword co-occurrences. CoPub was initially developed for the analysis of microarray data, but we broadened the scope by implementing new technology and new thesauri. In CoPub 5.0, we integrated existing CoPub technology with new features, and provided a new advanced interface, which can be used to answer a variety of biological questions. CoPub 5.0 allows searching for keywords of interest and its relations to curated thesauri and provides highlighting and sorting mechanisms, using its statistics, to retrieve the most important abstracts in which the terms co-occur. It also provides a way to search for indirect relations between genes, drugs, pathways and diseases, following an ABC principle, in which A and C have no direct connection but are connected via shared B intermediates. With CoPub 5.0, it is possible to create, annotate and analyze networks using the layout and highlight options of Cytoscape web, allowing for literature based systems biology. Finally, operations of the CoPub 5.0 Web service enable to implement the CoPub technology in bioinformatics workflows. CoPub 5.0 can be accessed through the CoPub portal http://www.copub.org.

  17. Variations in monsoonal rainfall over the last 21 kyr inferred from sedimentary organic matter in Tung-Yuan Pond, southern Taiwan

    NASA Astrophysics Data System (ADS)

    Yang, Tien-Nan; Lee, Teh-Quei; Meyers, Philip A.; Song, Sheng-Rong; Kao, Shuh-Ji; Löwemark, Ludvig; Chen, Rou-Fei; Chen, Huei-Fen; Wei, Kuo-Yen; Fan, Cheng-Wei; Shiau, Liang-Jian; Chiang, Hong-Wei; Chen, Yue-Gau; Chen, Min-Te

    2011-11-01

    Changes in paleorainfall intensity linked to the strength of the East Asian (EA) summer monsoon since 21 cal kyr BP are inferred from the organic matter contents of a 15-m sediment core from Tung-Yuan Pond in southern Taiwan. High total organic carbon/total nitrogen (TOC/TN) values in association with increased TOC content suggest that more soil-derived material containing terrestrial organic matter (OM) was delivered to the lake during periods of increased runoff associated with extensive precipitation that resulted from intensified summer monsoons, whereas low values indicate OM possessing a dominant algal origin during weakened summer monsoons. Rainfall intensity in terms of the proportion of terrestrial OM was high in four periods: the last deglaciation (˜17.2 to ˜12.2 ka), the early Holocene (˜10.6 to ˜8.6 ka), the middle Holocene Thermal Optimum (˜7.7 to ˜5 ka) and the late Holocene (˜4.2 to ˜2 ka), whereas it was low in the intervening time periods. High TOC/TN values coincide with peak values of summer insolation, and thus the strongest EA summer monsoon during the early and middle Holocene; small drops in these ratios correspond to increasing and decreasing solar radiation in the deglacial period and the late Holocene, respectively. The four intervals with low TOC/TN ratios, as well as episodic drops of the ratios during the deglaciation and the early and late Holocene are concordant with the late last glacial (˜21 to ˜17.2 ka), the Oldest (˜14.8 ka), the Older (˜13.3 ka) and the Younger Dryas (˜13 to ˜11.5 ka), the 8.2 cold event (˜8.6-7.7 ka) and a late Holocene cold event (˜5-4.2 ka), and suggest a weakened EA summer monsoon during these times. Moreover, high frequency hydrological variability occurred during the early Holocene, heavy rainfall persisted during the middle Holocene, and precipitation intensity generally diminished after ˜5 ka. The Tung-Yuan Pond sediment record indicates that the TOC/TN ratio can be used as a

  18. Episodic release of CO2 from the high-latitude North Atlantic Ocean during the last 135 kyr

    NASA Astrophysics Data System (ADS)

    Ezat, Mohamed M.; Rasmussen, Tine L.; Hönisch, Bärbel; Groeneveld, Jeroen; Demenocal, Peter

    2017-02-01

    Antarctic ice cores document glacial-interglacial and millennial-scale variability in atmospheric pCO2 over the past 800 kyr. The ocean, as the largest active carbon reservoir on this timescale, is thought to have played a dominant role in these pCO2 fluctuations, but it remains unclear how and where in the ocean CO2 was stored during glaciations and released during (de)glacial millennial-scale climate events. The evolution of surface ocean pCO2 in key locations can therefore provide important clues for understanding the ocean's role in Pleistocene carbon cycling. Here we present a 135-kyr record of shallow subsurface pCO2 and nutrient levels from the Norwegian Sea, an area of intense CO2 uptake from the atmosphere today. Our results suggest that the Norwegian Sea probably acted as a CO2 source towards the end of Heinrich stadials HS1, HS4 and HS11, and may have contributed to the increase in atmospheric pCO2 at these times.

  19. An 800-kyr Record of Global Surface Ocean δ18Oand Implications for Ice Volume-Temperature Coupling

    NASA Astrophysics Data System (ADS)

    Shakun, J. D.; Lea, D. W.; Lisiecki, L. E.; Raymo, M. E.

    2015-12-01

    The sequence of feedbacks that characterized 100-kyr glacial cycles of the past million years remains uncertain, hampering an understanding of the interconnections between insolation, ice sheets, greenhouse gas forcing, and climate. Critical to addressing this issue is an accurate interpretation of the marine δ18O record, the main template for the Ice Ages. This study uses a global compilation of 49 paired sea surface temperature-planktonic δ18O records to extract the mean δ18O of surface ocean seawater over the past 800 kyr, which we interpret to dominantly reflect global ice volume. The results indicate that global surface temperature, inferred deep ocean temperature, and atmospheric CO2 decrease early during each glacial cycle in close association with one another, whereas major ice sheet growth occurs later in glacial cycles. These relationships suggest that ice volume may have exhibited a threshold response to global cooling, and that global deglaciations do not occur until after the growth of large ice sheets. This phase sequence also suggests that the ice sheets had relatively little feedback on global cooling. Simple modeling shows that the rate of ice volume change through time is largely determined by the combined influence of insolation, temperature, and ice sheet size, with possible implications for the evolution of glacial cycles over the past three million years.

  20. Episodic release of CO2 from the high-latitude North Atlantic Ocean during the last 135 kyr

    PubMed Central

    Ezat, Mohamed M.; Rasmussen, Tine L.; Hönisch, Bärbel; Groeneveld, Jeroen; deMenocal, Peter

    2017-01-01

    Antarctic ice cores document glacial-interglacial and millennial-scale variability in atmospheric pCO2 over the past 800 kyr. The ocean, as the largest active carbon reservoir on this timescale, is thought to have played a dominant role in these pCO2 fluctuations, but it remains unclear how and where in the ocean CO2 was stored during glaciations and released during (de)glacial millennial-scale climate events. The evolution of surface ocean pCO2 in key locations can therefore provide important clues for understanding the ocean's role in Pleistocene carbon cycling. Here we present a 135-kyr record of shallow subsurface pCO2 and nutrient levels from the Norwegian Sea, an area of intense CO2 uptake from the atmosphere today. Our results suggest that the Norwegian Sea probably acted as a CO2 source towards the end of Heinrich stadials HS1, HS4 and HS11, and may have contributed to the increase in atmospheric pCO2 at these times. PMID:28224985

  1. Episodic release of CO2 from the high-latitude North Atlantic Ocean during the last 135 kyr.

    PubMed

    Ezat, Mohamed M; Rasmussen, Tine L; Hönisch, Bärbel; Groeneveld, Jeroen; deMenocal, Peter

    2017-02-22

    Antarctic ice cores document glacial-interglacial and millennial-scale variability in atmospheric pCO2 over the past 800 kyr. The ocean, as the largest active carbon reservoir on this timescale, is thought to have played a dominant role in these pCO2 fluctuations, but it remains unclear how and where in the ocean CO2 was stored during glaciations and released during (de)glacial millennial-scale climate events. The evolution of surface ocean pCO2 in key locations can therefore provide important clues for understanding the ocean's role in Pleistocene carbon cycling. Here we present a 135-kyr record of shallow subsurface pCO2 and nutrient levels from the Norwegian Sea, an area of intense CO2 uptake from the atmosphere today. Our results suggest that the Norwegian Sea probably acted as a CO2 source towards the end of Heinrich stadials HS1, HS4 and HS11, and may have contributed to the increase in atmospheric pCO2 at these times.

  2. Accumulation Rates of Trace Elements in the Cariaco Basin-A 20-kyr History of Seawater Chemistry and Global Climate

    NASA Astrophysics Data System (ADS)

    Piper, D. Z.; Dean, W. E.

    2002-12-01

    A sediment core from the Cariaco Basin on the Venezuelan continental shelf, which collected sediment as old as 20 kyr, was analyzed for its major-element-oxide and trace-element concen-trations. The elements can be partitioned between a siliciclastic, terrigenous-derived fraction and two seawater-derived fractions. The marine fractions are (1) a biogenic fraction represented by nutrient trace elements taken up mostly by phytoplankton in the photic zone, and (2) a hydroge-nous fraction derived from bottom water via adsorption and precipitation reactions. The present-day export of organic matter from the photic zone, redox conditions and advection of bottom water, and the flux of terrigenous debris into the basin are used to calculate current trace-element accu-mulation rates. The sums of calculated accumulation rates of Cd, Cu, Mo, Ni, V, and Zn show excellent agreement with their measured bulk rates of accumulation in the uppermost surface sediment. This agreement between current measured and calculated accumulation rates of trace elements supports a model of trace-element accumulation rates in the subsurface sediment that gives a 20-kyr history of upwelling into the photic zone, bottom-water advection, and sediment provenance. Extrema in the trace-element accumulation rates and interpreted hydrographic properties of the water column correspond to changes in eustatic sea level and global climate.

  3. Radiocarbon dating from 40 to 60 ka BP at Border Cave, South Africa

    NASA Astrophysics Data System (ADS)

    Bird, M. I.; Fifield, L. K.; Santos, G. M.; Beaumont, P. B.; Zhou, Y.; di Tada, M. L.; Hausladen, P. A.

    2003-04-01

    We present 21 radiocarbon dates on 19 charcoal samples from the sedimentary sequence preserved in Border Cave, South Africa. The background radiocarbon activity for charcoal from the cave was determined to be 0.050±0.018 percent modern carbon, from the analysis of a radiocarbon-dead sample from unit 5WA. Radiocarbon ages for individual samples ranged from 25.2 to >58.2 ka BP. The error-weighted mean ages for successively older strata are 38.5+0.85/-0.95 ka BP for unit 1WA, 50.2+1.1/-1.0 ka BP for units 2BS.LR.A and 2BS.LR.B, 56.5+2.7/-2.0 ka BP for unit 2BS.LR.C and 59.2+3.4/-2.4 ka BP for unit 2WA. This radiocarbon chronology is consistent with independent chronologies derived from electron spin resonance and amino acid racemization dating. The results therefore provide further evidence that radiocarbon dating of charcoal by the ABOX-SC technique can yield reliable radiocarbon ages beyond 40 ka BP. They also imply that Border Cave 5, a modern human mandible, predates >58.2 ka BP and that the Middle Stone Age (Mode 3)—Later Stone Age (Mode 5) transition of Border Cave was largely effected between ˜56.5 and ˜41.6 ka ago.

  4. Development and comparison of layer-counted chronologies from the WAIS Divide and EDML ice cores, Antarctica, over the last glacial transition (10-15 ka BP)

    NASA Astrophysics Data System (ADS)

    Winstrup, Mai; Vinther, Bo M.; Sigl, Michael; McConnell, Joe; Svensson, Anders M.; Wegner, Anna

    2014-05-01

    Some ice cores can be very precisely dated far back in time by counting the annual layering in various impurity records, and the most robust chronologies rely on the parallel analysis of annual features expressed in multiple data sets. Layer-counted Antarctic ice-core chronologies are now emerging: Multi-parameter layer counting has been carried out for the Holocene and late glacial section of the EDML ice core, Dronning Maud Land (Vinther et al., in prep.), and a layer-counted timescale for the WAIS Divide core, West Antarctica, reaching back to 30 kyr BP, was recently completed (WDC06A-7; WAIS Divide Members, 2013). Beyond 24 kyr b2k, the main part of this timescale relies solely on electrical measurements on the core. We here use a novel statistical framework for automated annual layer counting (Winstrup et al., 2012) to extend and improve the two chronologies from EDML and WAIS Divide. Using this method, we have 1) revised the multi-parameter layer counts for the EDML ice core back to 15 kyr BP, and 2) employed high-resolution chemistry measurements from WAIS Divide to obtain a layer-counted multi-parameter timescale for WAIS Divide over the same period (10-15 ka b2k). The EDML and WAIS Divide ice cores have been tightly synchronized using volcanic marker horizons, thus allowing a detailed comparison of annual layer counts between tie points using the various approaches. The corresponding timescales are compared also to the EDML timescale from the flow-model based AICC2012 chronology (Veres, 2012). For the Holocene section of the period (10-11.7 ka BP), all timescales show very good agreement. The peculiar accumulation anomaly observed in the WAIS Divide layer thicknesses in the beginning of the Holocene is confirmed by the multi-parameter layer counts from both WAIS Divide and EDML. The transition into the Holocene has generally proven a difficult period to date by annual layer counting, since the appearance of an annual layer in the various records can change

  5. Impella 5.0 as a Second-Line Mechanical Circulatory Support Strategy After Extracorporeal Life Support.

    PubMed

    Schibilsky, David; Kruger, Tobias; Lausberg, Henning F; Eisenlohr, Christoph; Haller, Christoph; Nemeth, Attila; Schibilsky, Barbara; Haeberle, Helene; Rosenberger, Peter; Walker, Tobias; Schlensak, Christian

    2016-09-01

    The catheter-based Impella 5.0 left ventricular assist device is a powerful and less invasive alternative for patients in cardiogenic shock. The use as second-line therapy in patients with precedent extracorporeal life support (ECLS) has not been described before now. We analyzed our experience of consecutive patients treated with this alternative strategy. From April 2014 to December 2014, eight patients had been implanted as a second-line option after ECLS support. The reason for the change from ECLS to Impella 5.0 was absence of cardiac recovery for primary weaning and complications of ECLS therapy. The mean time of ECLS support prior to Impella implantation was 12 ± 7 days. The implantation of the Impella 5.0/CP was technically successful in all patients, and the ECLS could be explanted in all eight patients who received Impella implantation as a second-line treatment. The second-line Impella 5.0 therapy resulted in two patients who turned into left ventricular assist device (LVAD) candidates, two primary weaning candidates, and four patients who died in the setting of sepsis or absent cardiac recovery and contraindications for durable LVAD therapy. Thereby, the overall hospital discharge survival as well as the 180-day survival was 50% for Impella 5.0 implantations as second-line procedure after ECLS. The latest follow-up survival of this second-line strategy after ECLS was three out of eight, as one patient died after 299 days of LVAD support due to sepsis. The use of Impella 5.0 constitutes a possible second-line therapeutic option for those patients who do not show cardiac recovery during prolonged ECLS support or suffer from complications of ECLS therapy. This treatment allows additional time for decisions regarding cardiac recovery or indication for durable LVAD therapy.

  6. The Environmental impact of the 8.2 and 9.2 kyr events in the UK.

    NASA Astrophysics Data System (ADS)

    Jones, Richard; Reinhardt, Liam; Halloran, Paul; Hatton, Jackie; Marshall, Jim

    2015-04-01

    The instability of the Early Holocene climate in NW Europe is due in part to the impact of freshwater pulses in the North Atlantic disrupting thermohaline circulation and reducing the northward transport of heat. Two of the most significant climatic episodes are the 8.2 and 9.2 kyr events, characterised by significant oxygen isotopic excursions in NW European lacustrine and speleothem records, the Greenland Ice-core record and changing SSTs in the North Atlantic sector. Assessing the impact of these two events on terrestrial systems is problematic due to the difficulty in identifying their signature in terrestrial archives. A sub-decadal oxygen isotope record from a Holocene micrite core from Hawes Water NW England provides unambiguous evidence for two significant isotopic excursions equivalent to the 9.2 and 8.2 kyr events. Lasting 50 and 150 yr respectively they are characterised by a slight cooling of around 1.6oC in mean July air temperatures (chironomid inferred). The environmental impact of each event was minimal, with no evidence for any significant changes in the range or abundance of plant taxa and no evidence for catchment instability. These results support the idea that the 8.2 and 9.2 kyr events are primarily a reflection of the changing isotopic composition of meteoric precipitation (δ18Op) and in the UK at least were of limited environmental significance. Analysis of subpolar gyre behaviour and atmospheric circulation across preindustrial control simulations from CMIP5, suggest that the negative isotopic excursions recorded at Hawes Water most likely reflect the influx of isotopically lighter moisture from the Arctic. An influx of freshwater down the Hudson River and into the North Atlantic Current could result in the development of low pressure anomalies over Scandinavia, bringing arctic air and moisture to the UK. This could be expected to produce the relatively minor decline in summer temperatures but would result in the significant negative shift

  7. Crossover from Peierls distortion to one-dimensional superconductivity in arrays of (5,0) carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Zhang, Ting; Sun, Ming Yuan; Wang, Zhe; Shi, Wu; Sheng, Ping

    2013-03-01

    We consider the electronic instabilities in (3,3)@(8,8) and (5,0)@(15,0) metallic double wall carbon nanotubes. Using 2rd order renormalization group method, we find that in the single wall (3,3) and (5,0) CNTs, the Peierls transition dominates, while if dressed with metallic outer shell, namely the (8,8) CNT and (15,0) CNT to form double wall carbon nanotube system(DWNT), the screening effect greatly reduces the Coulomb interaction of inner tubes, and supercondutivity(SS) instability is identified to be the groud state, although the crossover temperature of which SS response functions take over could be very low.

  8. Sea ice and millennial-scale climate variability in the Nordic seas 90 kyr ago to present.

    PubMed

    Hoff, Ulrike; Rasmussen, Tine L; Stein, Ruediger; Ezat, Mohamed M; Fahl, Kirsten

    2016-07-26

    In the light of rapidly diminishing sea ice cover in the Arctic during the present atmospheric warming, it is imperative to study the distribution of sea ice in the past in relation to rapid climate change. Here we focus on glacial millennial-scale climatic events (Dansgaard/Oeschger events) using the sea ice proxy IP25 in combination with phytoplankton proxy data and quantification of diatom species in a record from the southeast Norwegian Sea. We demonstrate that expansion and retreat of sea ice varies consistently in pace with the rapid climate changes 90 kyr ago to present. Sea ice retreats abruptly at the start of warm interstadials, but spreads rapidly during cooling phases of the interstadials and becomes near perennial and perennial during cold stadials and Heinrich events, respectively. Low-salinity surface water and the sea ice edge spreads to the Greenland-Scotland Ridge, and during the largest Heinrich events, probably far into the Atlantic Ocean.

  9. An improved north-south synchronization of ice core records around the 41 kyr 10Be peak

    NASA Astrophysics Data System (ADS)

    Raisbeck, Grant M.; Cauquoin, Alexandre; Jouzel, Jean; Landais, Amaelle; Petit, Jean-Robert; Lipenkov, Vladimir Y.; Beer, Juerg; Synal, Hans-Arno; Oerter, Hans; Johnsen, Sigfus J.; Steffensen, Jorgen P.; Svensson, Anders; Yiou, Françoise

    2017-03-01

    Using new high-resolution 10Be measurements in the NGRIP, EDML and Vostok ice cores, together with previously published data from EDC, we present an improved synchronization between Greenland and Antarctic ice cores during the Laschamp geomagnetic excursion ˜ 41 kyr ago. We estimate the precision of this synchronization to be ±20 years, an order of magnitude better than previous work. We discuss the implications of this new synchronization for making improved estimates of the depth difference between ice and enclosed gas of the same age (Δdepth), difference between age of ice and enclosed gas at the same depth (Δage) in the EDC and EDML ice cores, spectral properties of the 10Be profiles and phasing between Dansgaard-Oeschger-10 (in NGRIP) and AIM-10 (in EDML and EDC).

  10. Stratigraphic Correlation of an Excursion at 22 kyr in the U.S. Great Basin - the Hilina Pali Excursion?

    NASA Astrophysics Data System (ADS)

    Liddicoat, J. C.; Coe, R. S.

    2013-12-01

    An unusually large secular variation of the geomagnetic field recorded in outcrops of pluvial Lake Russell sediment about 22 kyr old in the Mono Basin, CA, can be used for precise correlation to other lacustrine sections in the western U.S., and perhaps beyond. We present new AF and thermal demagnetization results for paired samples at 2-cm intervals between ash layers 7 and 8 of Lajoie (1968) in the bank of Wilson Creek that document an excursion having an inclination as low as 16 degrees and as high as 73 degrees, while the declination swings from 15 degrees west during the low inclination to 30 east when the inclination is high, and back to average northerly declination and expected inclination. The corresponding VGPs form a narrow clockwise-trending loop centered at about 50 N, 30 E. The Mono Lake Excursion (MLE; Liddicoat and Coe, 1979) occurs 1.7 m lower in the same section. The best estimates for the ages of the two excursions are about 22 and 32 kyr, based on 14-C dates (Cassata et al., 2010). About 150 km to the north, sediments of about the same age exposed along the Truckee River that were deposited in pluvial Lake Lahontan record a similar geomagnetic signature. Moreover, both the MLE and this excursion are exhibited at the appropriate levels in a sediment core taken from Pyramid Lake, the remnant of Lake Lahontan (Benson et al., 2008). Thus, this excursion is a valuable marker for high-resolution correlation of Quaternary sediments in the western U.S., especially when paired with the MLE. It is tempting to try to identify this geomagnetic feature with others of about the same age further away. On the island of Hawaii, Coe et al. (1978) discovered a lava flow on the Hilina Pali with a calibrated 14-C age of 21 +/-1 kyr that has an inclination about 30 degrees shallower and a paleointensity 60 percent lower than today. Later Teanby et al. (2002) documented an excursion with inclinations as low as -35 degrees, recorded by around 40 successive flows with

  11. Sea ice and millennial-scale climate variability in the Nordic seas 90 kyr ago to present

    NASA Astrophysics Data System (ADS)

    Hoff, Ulrike; Rasmussen, Tine L.; Stein, Ruediger; Ezat, Mohamed M.; Fahl, Kirsten

    2016-07-01

    In the light of rapidly diminishing sea ice cover in the Arctic during the present atmospheric warming, it is imperative to study the distribution of sea ice in the past in relation to rapid climate change. Here we focus on glacial millennial-scale climatic events (Dansgaard/Oeschger events) using the sea ice proxy IP25 in combination with phytoplankton proxy data and quantification of diatom species in a record from the southeast Norwegian Sea. We demonstrate that expansion and retreat of sea ice varies consistently in pace with the rapid climate changes 90 kyr ago to present. Sea ice retreats abruptly at the start of warm interstadials, but spreads rapidly during cooling phases of the interstadials and becomes near perennial and perennial during cold stadials and Heinrich events, respectively. Low-salinity surface water and the sea ice edge spreads to the Greenland-Scotland Ridge, and during the largest Heinrich events, probably far into the Atlantic Ocean.

  12. Changes in dominant moisture sources and the consequences for hydroclimate on the northeastern Tibetan Plateau during the past 32 kyr

    NASA Astrophysics Data System (ADS)

    Thomas, Elizabeth K.; Huang, Yongsong; Clemens, Steven C.; Colman, Steven M.; Morrill, Carrie; Wegener, Pamela; Zhao, Jiangtao

    2016-01-01

    Lake Qinghai, located on the northeastern Tibetan Plateau north of the modern maximum summer monsoon extent, is well situated to record northward advances of the summer monsoon. Existing paleoclimate records contain conflicting evidence for the timing of summer monsoon advance into this region: an early arrival pre-Younger Dryas or a late arrival at the beginning of the Holocene. A 30-kyr-long leaf wax hydrogen isotope (n-alkanoic acid, δ2Hwax) record from Lake Qinghai helps to address this discrepancy by elucidating changes in the three main moisture sources in this region: southerly (summer monsoon), northwesterly, and local precipitation. Lake Qinghai δ2Hwax indicates that the arid glacial period was dominated by northwesterly moisture. Extremely arid conditions prevailed from 15 to 14 ka, likely because westerly winds were weakening and the summer monsoon had not yet reached this region. This arid period ended by 13.6 ka when small amounts of summer monsoon precipitation reached Lake Qinghai. Summer monsoon moisture subsequently retreated off of the northeastern Tibetan Plateau during the Younger Dryas and re-advanced in the early Holocene. Summer monsoon precipitation decreased progressively throughout the Holocene in response to decreasing summer insolation, and the modern northwesterly- and local-dominated moisture regime was attained ca. 2.6 ka. Lake Qinghai δ2Hwax demonstrates that the summer monsoon extent was dynamic during the past 30 kyr, responding dramatically to insolation and North Atlantic circulation changes. Moreover, Lake Qinghai δ2Hwax demonstrates that local and northwesterly air masses are important moisture sources to the northeastern Tibetan Plateau, and should be considered when reconstructing past hydroclimate in this region.

  13. Stalagmite-inferred centennial variability of the Asian summer monsoon in southwest China between 58 and 79 ka BP

    NASA Astrophysics Data System (ADS)

    Zhang, Tao-Tao; Li, Ting-Yong; Cheng, Hai; Edwards, R. Lawrence; Shen, Chuan-Chou; Spötl, Christoph; Li, Hong-Chun; Han, Li-Yin; Li, Jun-Yun; Huang, Chun-Xia; Zhao, Xin

    2017-03-01

    We use a new spliced stalagmite oxygen isotope record from Yangkou Cave and Xinya Cave, Chongqing, southwest China, to reconstruct the centennial-millennial-scale changes in Asian Summer Monsoon (ASM) intensity between 58.0 and 79.3 thousand years before present (ka BP, before AD 1950). This multidecadally resolved record shows four strong ASM periods, corresponding to Greenland Interstadials (GIS) 17-20, and three weak ASM episodes, among which, the one starting at 61.5 ± 0.2 ka BP and ending at 59.4 ± 0.2 ka BP that may correlate with Heinrich Event 6. The close agreement of climate events between China and Greenland supports the notion that the ASM is dominantly governed by high-latitude forcings in the Northern Hemisphere. The short-lived interstadial GIS 18, however, lasted for over 3 kyr in the records derived from ASM region, reflecting a gradual decline of ASM intensity, which coincides with a millennial-scale warming trend in Antarctica. This suggests an additional forcing of the ASM by the Southern Hemisphere, which also affected GIS 8-12, H4 and H5, as shown by previous speleothem studies from the ASM region.

  14. LGALS3BP — EDRN Public Portal

    Cancer.gov

    LGALS3BP is a secreted protein that binds to a human macrophage-associated lectin known as Mac-2 and also binds galectin 1. Elevated levels of LGALS3BP have been found in the serum of patients with cancer and in those infected by the human immunodeficiency virus (HIV).

  15. Diatom diversity and paleoenvironmental changes in Laguna Potrok Aike, Patagonia: the ~ 50 kyr PASADO sediment record

    NASA Astrophysics Data System (ADS)

    Recasens, C.; Ariztegui, D.; Maidana, N. I.

    2012-12-01

    Laguna Potrok Aike is a maar lake located in the southernmost Argentinean Patagonia, in the province of Santa Cruz. Being one of the few permanent lakes in the area, it provides an exceptional and continuous sedimentary record. The sediment cores from Laguna Potrok Aike, obtained in the framework of the ICDP-sponsored project PASADO (Potrok Aike Maar Lake Sediment Archive Drilling Program), were sampled for diatom analysis in order to reconstruct a continuous history of hydrological and climatic changes since the Late Pleistocene. Diatoms are widely used to characterize and often quantify the impact of past environmental changes in aquatic systems. We use variations in diatom concentration and in their dominant assemblages, combined with other proxies, to track these changes. Diatom assemblages were analyzed on the composite core 5022-2CP with a multi-centennial time resolution. The total composite profile length of 106.09 mcd (meters composite depth) was reduced to 45.80 m cd-ec (event-corrected composite profile) of pelagic deposits once gaps, reworked sections, and tephra deposits were removed. This continuous deposit spans the last ca. 51.2 cal. ka BP. Previous diatomological analysis from the core catcher samples of core 5022-1D, allowed us to determine the dominant diatom assemblages in this lake and select the sections where higher temporal resolution was needed. Over 200 species, varieties and forms were identified in the sediment record, including numerous endemic species and others which can be new to science. Among these, a new species has been described: Cymbella gravida sp. nov. Recasens and Maidana. The quantitative analysis of the sediment record reveals diatom abundances reaching 460 million valves per gram of dry sediment, with substantial fluctuations through time. Variations in the abundance and species distribution point toward lake level variations, changes in nutrient input or even periods of ice-cover in the lake. The top meters of the record

  16. G141.2+5.0, A NEW PULSAR WIND NEBULA DISCOVERED IN THE CYGNUS ARM OF THE MILKY WAY

    SciTech Connect

    Kothes, R.; Foster, T. J.; Sun, X. H.; Reich, W.

    2014-04-01

    We report the discovery of the new pulsar wind nebula (PWN) G141.2+5.0 in data observed with the Dominion Radio Astrophysical Observatory's Synthesis Telescope at 1420 MHz. The new PWN has a diameter of about 3.'5, which translates to a spatial extent of about 4 pc at a distance of 4.0 kpc. It displays a radio spectral index of α ≈ –0.7, similar to the PWN G76.9+1.1. G141.2+5.0 is highly polarized up to 40% with an average of 15% in the 1420 MHz data. It is located in the center of a small spherical H I bubble, which is expanding at a velocity of 6 km s{sup –1} at a systemic velocity of v {sub LSR} = –53 km s{sup –1}. The bubble could be the result of the progenitor star's mass loss or the shell-type supernova remnant (SNR) created by the same supernova explosion in a highly advanced stage. The systemic LSR velocity of the bubble shares the velocity of H I associated with the Cygnus spiral arm, which is seen across the second and third quadrants and an active star-forming arm immediately beyond the Perseus arm. A kinematical distance of 4 ± 0.5 kpc is found for G141.2+5.0, similar to the optical distance of the Cygnus arm (3.8 ± 1.1 kpc). G141.2+5.0 represents the first radio PWN discovered in 17 years and the first SNR discovered in the Cygnus spiral arm, which is in stark contrast with the Perseus arm's overwhelming population of shell-type remnants.

  17. Sources of ambient concentrations and chemical composition of PM 2.5-0.1 in Cork Harbour, Ireland

    NASA Astrophysics Data System (ADS)

    Hellebust, S.; Allanic, A.; O'Connor, I. P.; Jourdan, C.; Healy, D.; Sodeau, J. R.

    2010-02-01

    Particulate matter (PM 10-2.5 and PM 2.5-0.1) has been collected over a period of one year in Cork Harbour, Ireland, using a high-volume cascade impactor and polyurethane foam collection substrate. Collected PM 2.5-0.1 was analysed for water-soluble inorganic ions and metal content using ion chromatography and inductively coupled plasma-optical emission spectroscopy. On average approximately 50% by mass of the chemical content of PM was identified. The motivation for the study was to assess the potential impact of shipping emissions on air quality in Cork Harbour and City, with a view to informing public health impacts. The average ambient concentration of PM 10 between May 2007 and April 2008 was 4.6 µgm - 3 and the maximum concentration measured in one sample, representing a 4 day collection period, was 16 µgm - 3 . The major inorganic constituents identified in PM collected in Haulbowline Island in Cork Harbour were sulfate, ammonium, nitrate, chloride and sodium ions, which were mainly attributable to sea salt and secondary inorganic aerosols from regional sources. The results were analysed by principal component analysis for the purpose of source apportionment. Four factors were identified explaining over 80% of the data set variance. The factors were: shipping, sea salt, crustal material and secondary inorganic aerosols (SIA). The smaller size fraction was frequently observed to dominate, as the average concentration was 2.77 µgm - 3 for PM 2.5-0.1 compared to 1.9 µgm - 3 for PM 10-2.5. Fresh ship plumes were not found to make a significant contribution to primary PM 2.5-0.1 concentrations adjacent to the shipping channel. However, this was partially attributed to the ultrafine nature of ship emissions and the majority of the toxic metal content was attributed to emissions associated with heavy oil combustion sources, which include ship engines.

  18. Rare earth element and Pb isotope variations in a 52 kyr peat core from Lynch’s Crater (NE Queensland, Australia): Proxy development and application to paleoclimate in the Southern Hemisphere

    NASA Astrophysics Data System (ADS)

    Kylander, M. E.; Muller, J.; Wüst, R. A. J.; Gallagher, K.; Garcia-Sanchez, R.; Coles, B. J.; Weiss, D. J.

    2007-02-01

    Accurate prediction of future climate scenarios is contingent on our understanding of past and present climate mechanisms. This is done in part through the reconstruction of historical climate changes using proxy records from terrestrial and marine archives. Terrestrial archives covering the Holocene and late Pleistocene are limited, most acutely in the Southern Hemisphere. Here, Rare earth elements (REE) and Pb isotopes are developed as inorganic geochemical proxies of mineral dust source changes and, by extension, climate change. Using a peat core from Lynch's Crater in NE Queensland, Australia, we present the first long-term (c. 52 kyr) terrestrial record of atmospheric REE and Pb deposition (with the exception of four wet events which represent periods of erosion from the crater itself) in the Southern Hemisphere covering both glacial and interglacial times. Based on a combination of correlation analyses, Al and Ti normalised profiles and elemental patterns, we establish REE are immobile within the peat deposit and not subject to significant post depositional diagenetic changes (important particularly for Ce). This is vital as REE can be mobile under acid and organic rich conditions like those that can occur during the development of a peat deposit. The volcanic provinces of eastern Australia have characteristic Eu anomaly signatures, which allowed their use in a novel way to detect changes in dust source to Lynch's Crater. Between 41,095 and 52,505 BP the deposit was under the influence of dust carried by long distance transport (>1500 km) from SE Australia. From 8525 to 40,815 BP regional sources (100-1500 km) dominated the deposited signals while between 1740 and 8390 BP the dust signal was controlled by local sources (<100 km). These findings were also confirmed by Pb isotope data. Changepoint modelling refined the timing of these changes in dust source, recognizing concurrent shifts in our tracing tools ((Eu/Eu ∗) PAAS and 206Pb/ 207Pb). These

  19. Noncovalent and covalent functionalization of a (5, 0) single-walled carbon nanotube with alanine and alanine radicals.

    PubMed

    Rajarajeswari, Muthusivarajan; Iyakutti, Kombiah; Kawazoe, Yoshiyuki

    2012-02-01

    We have systematically investigated the noncovalent and covalent adsorption of alanine and alanine radicals, respectively, onto a (5, 0) single-walled carbon nanotube using first-principles calculation. It was found that XH···π (X = N, O, C) interactions play a crucial role in the non-ovalent adsorption and that the functional group close to the carbon nanotube exhibits a significant influence on the binding strength. Noncovalent functionalization of the carbon nanotube with alanine enhances the conductivity of the metallic (5, 0) nanotube. In the covalent adsorption of each alanine radical onto a carbon nanotube, the binding energy depends on the adsorption site on CNT and the electronegative atom that binds with the CNT. The strongest complex is formed when the alanine radical interacts with a (5, 0) carbon nanotube through the amine group. In some cases, the covalent interaction of the alanine radical introduces a half-filled band at the Fermi level due to the local sp (3) hybridization, which modifies the conductivity of the tube.

  20. Linking sediment-charcoal records and ecological modeling to understand causes of fire-regime change in boreal forests.

    PubMed

    Brubaker, Linda B; Higuera, Philip E; Rupp, T Scott; Olson, Mark A; Anderson, Patricia M; Hu, Feng Sheng

    2009-07-01

    Interactions between vegetation and fire have the potential to overshadow direct effects of climate change on fire regimes in boreal forests of North America. We develop methods to compare sediment-charcoal records with fire regimes simulated by an ecologica model, ALFRESCO (Alaskan Frame-based Ecosystem Code) and apply these methods to evaluate potential causes of a mid-Holocene fire-regime shift in boreal forests of the south-central Brooks Range, Alaska, U.S.A. Fire-return intervals (FRIs, number of years between fires) are estimated over the past 7000 calibrated 14C years (7-0 kyr BP [before present]) from short-term variations in charcoal accumulation rates (CHARs) at three lakes, and an index of area burned is inferred from long-term CHARs at these sites. ALFRESCO simulations of FRIs and annual area burned are based on prescribed vegetation and climate for 7-5 kyr BP and 5-0 kyr BP, inferred from pollen and stomata records and qualitative paleoclimate proxies. Two sets of experiments examine potential causes of increased burning between 7-5 and 5-0 kyr BP. (1) Static-vegetation scenarios: white spruce dominates with static mean temperature and total precipitation of the growing season for 7-0 kyr BP or with decreased temperature and/or increased precipitation for 5-0 kyr BP. (2) Changed-vegetation scenarios: black spruce dominates 5-0 kyr BP, with static temperature and precipitation or decreased temperature and/or increased precipitation. Median FRIs decreased between 7-5 and 5-0 kyr BP in empirical data and changed-vegetation scenarios but remained relatively constant in static-vegetation scenarios. Median empirical and simulated FRIs are not statistically different for 7-5 kyr BP and for two changed-vegetation scenarios (temperature decrease, precipitation increase) for 5-0 kyr BP. In these scenarios, cooler temperatures or increased precipitation dampened the effect of increased landscape flammability resulting from the increase in black spruce. CHAR

  1. Interoperability of wearable cuffless BP measuring devices.

    PubMed

    Liu, Jing; Zhang, Yuan-Ting

    2014-01-01

    While a traditional cuff-based Blood Pressure (BP) measuring device can only take a snap shot of BP, real-time and continuous measurement of BP without an occluding cuff is preferred which usually use the pulse transit time (PTT) in combination with other physiological parameters to estimate or track BP over a certain period of time after an initial calibration. This article discusses some perspectives of interoperability of wearable medical devices, based on IEEE P1708 draft standard that focuses on the objective performance evaluation of wearable cuffless BP measuring devices. The ISO/IEEE 11073 family of standards, supporting the plug-and play feature, is intended to enable medical devices to interconnect and interoperate with other medical devices and with computerized healthcare information systems in a manner suitable for the clinical environment. In this paper, the possible adoption of ISO/IEEE 11073 for the interoperability of wearable cuffless BP devices is proposed. In the consideration of the difference of the continuous and cuffless BP measuring methods from the conventional ones, the existing device specialization standards of ISO/IEEE 11073 cannot be directly followed when designing the cuffless BP device. Specifically, this paper discusses how the domain information model (DIM), in which vital sign information is abstracted as objects, is used to structure the information about the device and that generated from the device. Though attention should also be paid to adopt the communication standards for other parts for the communication system, applying communication standards that enable plug-and-play feature allows achieving the interoperability of different cuffless BP measuring devices with possible different configurations.

  2. Catastrophic flank collapses and slumping in Pico Island during the last 130 kyr (Pico-Faial ridge, Azores Triple Junction)

    NASA Astrophysics Data System (ADS)

    Costa, A. C. G.; Hildenbrand, A.; Marques, F. O.; Sibrant, A. L. R.; Santos de Campos, A.

    2015-09-01

    The Pico Island constitutes the easternmost sub-aerial domain of a steep WNW-ESE volcanic ridge, which has developed within the Nubia-Eurasia diffuse plate boundary (Azores Triple Junction). The island comprises three volcanic systems, from older to younger: the Topo Volcano, the Fissural System, and the Pico Stratovolcano. From a high-resolution Digital Elevation Model (10 m), and new bathymetric, stratigraphic, structural, and high-precision K-Ar data, we reconstruct the main successive stages of growth and partial destruction of the island over the last 200 kyr. We especially concentrate on the central sector of the island, which has recorded gradual movements through slumping and catastrophic flank collapses since ca. 130 kyr. The remmants of the Topo Volcano are partly exposed on Pico's SE flank, and are here dated between 186 ± 5 and 115 ± 4 ka. Topo was significantly destroyed by N- and S-directed large-scale flank collapses between ca. 125 and 70 ka. On Pico's N flank, collapse seems to have removed all the unstable material, but in the S the collapse structure is composite, including a major flank collapse and a remnant slump complex that is still active. A first episode of deformation occurred between ca. 125 and 115 ka along the master fault of the slump. Between ca. 115 and 69 ka, most of the unstable material was removed by a major flank collapse, leaving behind a still considerable volume of unstable material that comprises the active slump. This first collapse was catastrophic and generated a large debris deposit recognized on the high-resolution bathymetry, with a minimum run-out of ca. 17 km. The scar was partially filled by volcanic products erupted from volcanic cones developed within the slump depression, and possibly also from the early WNW-ESE Fissural System. Subsequent deformation in the slump area affected in part the filling units, leading to the individualization of secondary curved faults. Younger volcanic products have gradually

  3. A role for land surface forcing of North Atlantic climate and isotope signals during the 8.2kyr event?

    NASA Astrophysics Data System (ADS)

    Hopcroft, Peter; Valdes, Paul

    2014-05-01

    An important example of abrupt climate change occurred 8200 years ago in the North Atlantic and is generally known as the 8.2kyr event. This abrupt ~160 year cooling appears to coincide with the final drainage of the ice-dammed Lakes Agassiz and Ojibway. The resultant influx of meltwater to the North Atlantic is assumed to have perturbed the Atlantic Meridional Overturning circulation, reducing northward heat transport and causing widespread cooling. Numerous lines of evidence support this theory, with reconstructions showing changes in deep water formation, reductions in salinity and evidence of sea-level rise. Coupled general circulation model (GCM) simulations driven with realistic estimates of the meltwater flux show a regional cooling but fail to replicate the duration or the magnitude of this event in comparison with proxy archives. Meltwater injection was not the only rapid climate forcing in operation at this time. Drainage of the pro-glacial lakes would have had a profound effect on the boundary layer heat fluxes over North America, with potential teleconnections further afield. In this work we use an isotope-enabled version of the coupled GCM HadCM3 with boundary conditions appropriate for the time period of 9kyr (including ice sheets, greenhouse gases and orbital parameters). This model tracks oxygen isotopes throughout the hydrological cycle allowing more robust comparison with proxy archives. We analyse the impact of the removal of a lake area corresponding to Lakes Agassiz and Ojibway at this time and present sensitivity tests designed to analyse the contributions from lake removal, orographic change and the assumed isotopic content of the pro-glacial lakes. The results show a distinct pattern of cooling across North America (in the annual mean) with an apparent teleconnection to the Barents Sea, where there is warming associated with sea-ice reduction. The isotopic implications depend on the initial isotopic content of the pro-glacial lake. Assuming

  4. Benthic foraminiferal δ18O-Mg/Ca from the SE Nordic seas during the last 65 kyr

    NASA Astrophysics Data System (ADS)

    Ezat, M.; Rasmussen, T. L.; Groeneveld, J.

    2013-12-01

    Benthic foraminiferal δ18O-Mg/Ca from the SE Nordic seas during the last 65 kyr Mohamed M. Ezat1,2*, Tine L. Rasmussen1, Jeroen Groeneveld3 1 CAGE - Centre for Arctic Gas Hydrate, Environment and Climate, and Department of Geology, University of Tromsø, NO-9037 Tromsø, Norway. 2 Department of Geology, Faculty of Science, Beni-Suef University, Beni-Suef, Egypt. 3 Department of Geosciences, University of Bremen, Klagenfurter Strasse, 28359, Bremen, Germany. * e-mail: mohamed.ezat@uit.no The climate during the last glacial period underwent rapid millennial-scale variability known as Dansgaard-Oeschger (DO) events of warm interstadials and cold stadials. DO events are manifested in marine and continental records in the circum-North Atlantic region and throughout the globe. Several studies suggest a crucial role of the Nordic seas in regulating the climate during the last glacial period. Previous studies from the Nordic seas revealed low benthic δ18O values during stadials and high values during interstadials. The causes of the depletions in benthic 18O during stadials are highly debated. Sinking of isotope depleted-brines formed due to sea ice production has previously been proposed. Another explanation has indicated warming of the intermediate water in the Nordic seas based on the finding of warm water benthic foraminiferal species during stadials. Here we present the first benthic foraminiferal Mg/Ca-based bottom water temperature (BWT) record from the Nordic seas that, along with other proxies, aims to resolve the hydrographic changes at intermediate water depth on DO timescale during the last 65 kyr. The results show pronounced and gradual BWT increases during all cold stadials followed by an abrupt drop to modern-like BWT at interstadials onsets. The increase in BWT, caused by the subsurface inflow of warm Atlantic intermediate water, substantially contributed to the halocline collapse and onset of interstadial conditions throughout complex ocean-sea ice

  5. Functionalized single-walled carbon nanotube (5, 0) as a carrier for isoniazid — A tuberculosis drug

    NASA Astrophysics Data System (ADS)

    Rajarajeswari, M.; Iyakutti, K.; Lakshmi, I.; Rajeswarapalanichamy, R.; Kawazoe, Y.

    2015-06-01

    Nanostructures functionalized with amino acid are able to penetrate the cell wall. In this first principle study, we have demonstrated that the amino acid alanine functionalized carbon nanotubes (CNTs) (5, 0) can be a drug carrier for the tuberculosis drug isoniazid. Isoniazid is binding with both the non-covalently and covalently functionalized CNTs through the π-π stacking and NH⋯π interactions. The planar structure of isoniazid and hydrophobic nature of CNT promote the π-π stacking interactions. The amine group present in the isoniazid enables the NH⋯π interaction with the delocalized π electron cloud of CNT.

  6. The millimetre spectrum of BP Cru

    NASA Astrophysics Data System (ADS)

    Pestalozzi, Michele; Hobbs, George; Torkelsson, Ulf

    2010-04-01

    In this experiment we attempt to detect the millimetre emission from the high-mass X-ray binary BP Cru. This object is composed of a hypergiant (Wray 977) and a slow spinning X-ray pulsar (GX301-2). The recent ATCA observations of centimeter emission (Pestalozzi et al. 2009, this was the first detection of radio emission towards BP Cru) suggested that radio emission consists of two components, a transient non-thermal one and a persistent thermal one, probably arising from the large stellar wind of Wray 977. As stellar winds often show a positive spectral index, we ask to observe BP Cru at 13 and 7 mm, where we expect fluxes of around 1 mJy. Any detection will allow us to probe the inner parts of the wind and characterise the structure of the stellar wind of BP Cru. For this detection experiment we require 11 hours of observations with ATCA.

  7. BP: synthesis and properties of boron phosphide

    NASA Astrophysics Data System (ADS)

    Woo, Katherine; Lee, Kathleen; Kovnir, Kirill

    2016-07-01

    Cubic boron phosphide, BP, is notorious for its difficult synthesis, thus preventing it from being a widely used material in spite of having numerous favorable technological properties. In the current work, three different methods of synthesis are developed and compared: from the high temperature reaction of elements, Sn flux assisted synthesis, and a solid state metathesis reaction. Structural and optical properties of the products synthesized from the three methods were thoroughly characterized. Solid state metathesis is shown to be the cleanest and most efficient method in terms of reaction temperature and time. Synthesis by Sn flux resulted in a novel Sn-doped BP compound. Undoped BP samples exhibit an optical bandgap of ∼2.2 eV while Sn-doped BP exhibits a significantly smaller bandgap of 1.74 eV. All synthesized samples show high stability in concentrated hydrochloric acid, saturated sodium hydroxide solutions, and fresh aqua regia.

  8. PSR J1833-1034, the Very Young Pulsar in SNR G21.5-0.9

    NASA Astrophysics Data System (ADS)

    Camilo, Fernando; Gaensler, Bryan; Manchester, Dick; Ransom, Scott; Lorimer, Duncan Ross

    2007-04-01

    We have been timing the very young pulsar PSR J1833-1034, recently discovered near the center of the supernova remnant (SNR) G21.5-0.9 (Camilo et al. 2006). With 16 months of timing data in hand we have confirmed that the pulsar is coincident, to sub-arcsec precision, with the centrally-peaked X-ray source visible in Chandra data near the center of G21.5-0.9 and have therefore confirmed this pulsar-SNR association beyond any doubt. More unexpectedly, we have been able to measure this pulsar's braking index, n = 2.18, only the 6th such phase-coherent measurement done in over 1700 pulsars known. We now have a chance to measure the "second braking index" and place further constraints on the spin-down law obeyed by this pulsar. This has been done to date for only 2 pulsars. Finally, we wish to continue timing this pulsar because it will be one of the prime candidates for gamma-ray detection with the GLAST satellite to be launched in 2007, and in order to do so we must maintain its timing solution. For these reasons we request 24 hr for timing PSR J1833-1034 during the present semester.

  9. Effect of Sintering Temperature on the Structure and Bioactivity of HAp-5.0wt.%SO2 Bioceramic Composites

    NASA Astrophysics Data System (ADS)

    Li, Xiao-Wu; Zhang, Xue; Zhang, Pei-Lun; Yasuda, Hiroyuki; Umakoshi, Yukichi

    2011-06-01

    Bioceramic composites were synthesized by sintering the powders of hydroxyapatite (HAp) mixed directly with additive of 5.0wt.%SiO2 at different temperatures ranging from 800°C to 1200°C. X-ray diffraction analysis indicated that the phase transformation from HAp to tricalcium phosphate (TCP) began to take place as the sintering temperature is as high as 900°C, and the content of TCP phase increased notably with increasing temperature. Microstructural observations demonstrated that a distinctive microstructure featuring crystalline clusters with different sizes surrounded by glassy matrix formed in HAp-5.0wt.%SO2 bio-composites, as the sintering temperature reached 1100°C. Soaking experiments in a stimulated body fluid revealed that the bio-composites showed a faster bone-like apatite layer growth, namely an enhanced in vitro bioactivity, as the sintering temperature increased, since the increase in sintering temperature promoted the phase transformation from HAp to TCP, which exhibits a higher solubility than HAp.

  10. Use of the Impella 5.0 Device as a Bridge to Recovery in Adult Fulminant Viral Myocarditis.

    PubMed

    Burns, Daniel J P; Quantz, Mackenzie A

    2015-01-01

    We present a case of a 48-year-old female patient successfully bridged to recovery with the Impella 5.0 microaxial pump (Abiomed, Danvers, MA USA) after presenting with cardiogenic shock secondary to acute fulminant viral myocarditis. After 1 week of flu-like symptoms, the patient presented to her community emergency department with chest pain and hypotension. A diagnosis of inferior ST elevation myocardial infarction was made; subsequent angiography demonstrated normal coronary arteries and a left ventricular ejection fraction of 10%. A provisional diagnosis of viral myocarditis was made. As her condition deteriorated further, she underwent insertion of an Impella 5.0 after failure of supportive medical therapy. Myocardial recovery occurred, and the Impella was removed after 1 week. After a prolonged cardiac intensive care unit stay requiring temporary hemodialysis, the patient recovered sufficiently to tolerate device explant, transfer to the recovery ward, and ultimate discharge home. This case report highlights the benefit of mechanical circulatory support in a patient with cardiogenic shock from viral myocarditis as well as some of the complications that can occur in this critically ill subset of patients.

  11. Thermal isolation of Campbell Plateau, New Zealand, by the Antarctic Circumpolar Current over the past 130 kyr

    NASA Astrophysics Data System (ADS)

    Neil, Helen L.; Carter, Lionel; Morris, Michele Y.

    2004-12-01

    Campbell Plateau occupies a key position in the southwest Pacific sector of the Southern Ocean. The plateau confines and steers the Antarctic Circumpolar Current (ACC) along its flanks, isolating the Subantarctic plateau from cold polar waters. Oxygen and carbon isotope records from Campbell Plateau cores provide new records of water mass stratification for the past 130 kyr. During glacial climes, strengthening of the Subantarctic Front (SAF) caused waters over the plateau flanks to be deeply mixed and ˜3°C cooler. Waters of the plateau interior remained stratified and isolated from the cold southern waters. In the west, waters cooled markedly (˜4°C) owing to reduced entrainment of Tasman Sea water. Marked cooling also occurred north of Campbell Plateau under increased entrainment of polar water by a branch of the SAF. The ACC remained along the flanks of Campbell Plateau during the last interglacial, when interior waters were stratified and warmer by ˜1°C than now.

  12. A paleomagnetic and relative paleointensity record from the Argentine Basin (western South Atlantic Ocean) for the last ~125 kyrs

    NASA Astrophysics Data System (ADS)

    Heil, C. W., Jr.; Stoner, J. S.; St-Onge, G.; King, J. W.

    2015-12-01

    The paucity of paleomagnetic records from the western South Atlantic Ocean presents a significant gap in our understanding of the spatial variations in geomagnetic field dynamics as they relate to the occurrence of geomagnetic excursions and changes in field strength. As such, high quality records from this region can help build upon Holocene observations and extend the geographic and temporal data coverage for spherical harmonic models. To that end, we present paleomagnetic directional (inclination) and strength (relative paleointensity) records from two cores from the Argentine Basin (RC11-49 and RC16-88). Although the cores were collected more than 40 years ago, the sediments appear to hold a stable remanence and reliable magnetic directions, as evidenced by their reproducibility between the two cores that are separated by ~25 km. The records show evidence of 4 excursional features in the uppermost 16-m of the sediments from the basin. A comparison of the relative paleointensity records from these cores to the South Atlantic Paleointensity Stack (SAPIS) (Stoner et al., 2002) and the relative paleointensity record from ODP Site 1089 (Stoner et al., 2003) indicate that the sediments reliably record relative changes in geomagnetic field intensity and suggests that the longest record (RC11-49) spans the last ~125 kyrs. Our results indicate that the sediments of the Argentine Basin are an important sedimentary archive of geomagnetic field behavior and strength at least through the Holocene and Late Pleistocene and highlight the need for further studies of cores within the basin.

  13. Export production in the subarctic North Pacific over the last 800 kyrs: No evidence for iron fertilization?

    USGS Publications Warehouse

    Kienast, S.S.; Hendy, I.L.; Crusius, J.; Pedersen, Thomas F.; Calvert, S.E.

    2004-01-01

    The subarctic North Pacific is a high nitrate-low chlorophyll (HNLC) region, where phytoplankton growth rates, especially those of diatoms, are enhanced when micro-nutrient Fe is added. Accordingly, it has been suggested that glacial Fe-laden dust might have increased primary production in this region. This paper reviews published palaeoceanographic records of export production over the last 800 kyrs from the open North Pacific (north of ???35??N). We find different patterns of export production change over time in the various domains of the North Pacific (NW and NE subarctic gyres, the marginal seas and the transition zone). However, there is no compelling evidence for an overall increase in productivity during glacials in the subarctic region, challenging the paradigm that dust-born Fe fertilization of this region has contributed to the glacial draw down of atmospheric CO2. Potential reasons for the lack of increased glacial export production include the possibility that Fe-fertilization rapidly drives the ecosystem towards limitation by another nutrient. This effect would have been exacerbated by an even more stable mixed layer compared to today. ?? The Oceanographic Society of Japan.

  14. Climate-related response of dust flux to the central equatorial Pacific over the past 150 kyr

    NASA Astrophysics Data System (ADS)

    Jacobel, A. W.; McManus, J. F.; Anderson, R. F.; Winckler, G.

    2017-01-01

    High resolution paleoclimate records from low latitudes are critical for understanding the role of the tropics in transmitting and generating feedbacks for high-latitude climate change on glacial-interglacial and millennial timescales. Here we present three new records of 230Thxs,0-normalized 232Th-derived dust fluxes from the central equatorial Pacific spanning the last 150 kyr at millennial-resolution. All three dust flux records share the "sawtooth" pattern characteristic of glacial-interglacial cycles in ice volume, confirming a coherent response to global climate forcing on long timescales. These records permit a detailed examination of millennial variability in tropical dust fluxes related to abrupt perturbations in oceanic and atmospheric circulation. Increases in dust flux in association with at least six of the longest Greenland stadials provide evidence that abrupt, high-latitude climate oscillations influenced the atmospheric aerosol load in the equatorial Pacific, with implications for both direct and indirect effects on the tropical energy balance. Our latitudinal transect of cores captures shifts in the position of the Intertropical Convergence Zone (ITCZ) in response to variations in the interhemispheric thermal gradient associated with cooling in Greenland and bipolar seesaw warming in Antarctica. These observations demonstrate that changes in the energy and hydrologic balance of the tropics were repeated features of the penultimate deglaciation, last glacial inception and last glacial cycle, and highlight the role of the tropical atmosphere as a dynamic and responsive component of Earth's climate system.

  15. Precessional control on ocean productivity in the Western Pacific Warm Pool for the last 400 kyr: Insight from biogenic magnetite

    NASA Astrophysics Data System (ADS)

    Yamazaki, Toshitsugu; Horiuchi, Kazuho

    2016-11-01

    Western Pacific Warm Pool plays a significant role in large-scale atmospheric circulation and global hydrology. We conducted an environmental magnetic study of two late Pleistocene sediment cores from the western equatorial Pacific Ocean offshore of New Guinea in order to better constrain climatic and oceanographic variability, particularly spatiotemporal ocean productivity variations. Magnetic property measurements and transmission electron microscopy reveal that the magnetic mineral assemblages in the studied sediments are a mixture of biogenic and terrigenous magnetite. Variations in the acid soluble sediment component, interpreted as carbonate content, and the proportion of biogenic to terrigenous magnetite estimated from the ratio of anhysteretic to saturation remanent magnetizations are in-phase with northern hemisphere summer insolation variations. We interpret that ocean productivity increased during insolation maxima, which induced higher populations of magnetotactic bacteria through a larger nutrient supply to the seafloor. This interpretation assumes that magnetotactic bacterial populations are greatest in sediments just below the seafloor. Precessional frequencies in magnetic mineral concentration variations are suppressed after correction for carbonate dilution, whereas cyclic changes with a ˜100 kyr periodicity remain in carbonate-free magnetic concentration variations. Glacial/interglacial changes in bottom water currents may have influenced transportation and deposition of magnetic minerals. We demonstrate the usefulness of magnetic proxies for paleoceanographic studies, particularly of biogenic magnetite proxies for estimating paleoproductivity variations.

  16. Palaeomagnetic intensities from 14C-dated lava flows on the Big Island, Hawaii: 0-21 kyr

    USGS Publications Warehouse

    Pressling, Nicola; Laj, Carlo; Kissel, Catherie; Champion, Duane E.; Gubbins, David

    2006-01-01

    Thellier–Thellier experiments were carried out on 216 lava samples collected by the USGS on the Big Island. 35 individual flows from the Kilauea, Mauna Loa and Hualalai volcanoes are represented and independent radiocarbon dating of the flows yields absolute ages ranging from 290 to 20,240 yrs old. The palaeomagnetic analysis was carried out at the Laboratoire des Sciences du Climat et de l'Environnement in Gif-sur-Yvette, France, in two custom built, large capacity furnaces that have been specifically designed to minimise oxidation. The temperature steps were adapted to accommodate the characteristic loss of magnetisation at low temperatures seen in the Curie balance results and the use of half-size samples allowed secondary experiments to be carried out where necessary. The strict PICRIT-03 selection criteria were rigorously applied to the data and a high success rate of 53% has been achieved on a sample level. The flow averaged results almost double the existing 14C-dated palaeointensity dataset for this time window and confirm a period of high intensity over the past 4 kyr preceded by a period in which the dipole moment was weaker. However, the values attained in this study are on average higher than previously published data; reliability of these values is discussed.

  17. Sea ice and millennial-scale climate variability in the Nordic seas 90 kyr ago to present

    PubMed Central

    Hoff, Ulrike; Rasmussen, Tine L.; Stein, Ruediger; Ezat, Mohamed M.; Fahl, Kirsten

    2016-01-01

    In the light of rapidly diminishing sea ice cover in the Arctic during the present atmospheric warming, it is imperative to study the distribution of sea ice in the past in relation to rapid climate change. Here we focus on glacial millennial-scale climatic events (Dansgaard/Oeschger events) using the sea ice proxy IP25 in combination with phytoplankton proxy data and quantification of diatom species in a record from the southeast Norwegian Sea. We demonstrate that expansion and retreat of sea ice varies consistently in pace with the rapid climate changes 90 kyr ago to present. Sea ice retreats abruptly at the start of warm interstadials, but spreads rapidly during cooling phases of the interstadials and becomes near perennial and perennial during cold stadials and Heinrich events, respectively. Low-salinity surface water and the sea ice edge spreads to the Greenland–Scotland Ridge, and during the largest Heinrich events, probably far into the Atlantic Ocean. PMID:27456826

  18. A SCALE 5.0 Reactor Physics Assessment using the Module TRITON against Mixed Oxide (MOX) OECD/NEA Benchmarks

    SciTech Connect

    Saccheri, J.G.B.; Diamond, D.J.

    2006-07-01

    Reactor physics numerical benchmarks have been performed at the Brookhaven National Laboratory (BNL) with the software package SCALE 5.0 and its TRITON module to assess their capability to predict neutronics parameters for mixed oxide (MOX) fuels. The results of such calculations are herein presented. Specifically, BNL results for neutron multiplication factors (kINF), neutron fluxes and fuel burnup have been added to published OECD/NEA benchmarks for MOX fuels and particular emphasis has been given to the impact of cross-section libraries and their energy structure on the results. Among the OECD/NEA published benchmarks two have been considered here: the first one models a fuel pin surrounded by moderator, in which two different MOX fuels can be introduced, and for each one of them kINF and neutron fluxes as a function of burnup are calculated. The second one includes both a fuel pin case and a macro-cell case (a heterogeneous 30 by 30 configuration of fuel pins), for which the void coefficient is determined by calculating kINF at zero burnup as a function of moderation. The calculations are repeated for several combinations of MOX and uranium oxide fuels using several different cross-section libraries. The final results have been compared with each other. This study shows that SCALE 5.0 (with TRITON) overall performs in line with the other codes in the benchmark, but the results are dependent on the energy group structure of the cross section libraries used. For instance, when fissile plutonium is increased in the fuel, TRITON results become slightly divergent with burnup (with respect to the other codes in the benchmark) and if the standard 44-group library provided with SCALE 5.0 is used void coefficient calculations become inadequate for very low void (below 10% of the operating value of moderator density). Moreover, the prediction capabilities of the code are shown to be dependent on the MOX fuel enrichment and the MOX isotopic composition. (authors)

  19. Abrupt Climate Change & Paleoindian Environments in western Colorado from 17-9 ka yr BP

    NASA Astrophysics Data System (ADS)

    Whitlock, C. L.; Briles, C.; Meltzer, D. J.

    2010-12-01

    The late-glacial period was characterized by rapid climate changes that resulted in significant ecosystem reorganizations worldwide. In western Colorado, one of the coldest locations in North American today, mountain environments during the late-glacial period are poorly known. Yet, archeological evidence indicates that Folsom-age Paleoindians were present in the region, perhaps even occasionally over-wintering in the Gunnison Basin during the Younger Dryas Chronozone (YDC; 12.9 to 11.5ka yr BP). To determine the climate, vegetation, and fire history during the late-glacial/early-Holocene transition, a 17-kyr-old sediment core from Lily Pond (38°56’06” N, 106°38’37”W, 3208m elevation) was analyzed for pollen and charcoal and compared with other high-resolution records from the region. The data suggest that, following deglaciation, the region supported an alpine parkland dominated by Artemisia and scattered Picea. Conditions warmed and became wetter than before during the Bølling-Allerød period (B/A; 14.7 to 12.9ka yr BP), when the region was covered by open Picea, Pinus, and Abies forest. Cooling during the YDC is inferred from abundant Picea, slightly more Artemisia and decreased Pinus, which indicate the presence of subalpine parkland. With the onset of the Holocene at ~11.5 ka yr BP, Pinus, Quercus, Artemisia, and Chenopodiaceae increased, suggesting an upslope expansion of xerophytic taxa in response to warmer and effectively drier summers than before or at present. Fire activity was absent prior to 14.7 ka yr BP, increased substantially during the B/A, decreased during the YDC, increased at the beginning of the Holocene, and declined in the early Holocene. The vegetation changes that occurred at Lily Pond are generally consistent with other high-resolution records in the Colorado Rockies in showing cooler-than-present YDC followed by rapid warming. The Lily Lake data provide new information that indicates substantial warming and establishment of

  20. Sediment Cd and Mo accumulation in the oxygen-minimum zone off western Baja California linked to global climate over the past 52 kyr

    USGS Publications Warehouse

    Dean, W.E.; Zheng, Yen; Ortiz, J.D.; VanGeen, A.

    2006-01-01

    Concentrations of organic carbon (orgC), cadmium (Cd), and molybdenum (Mo) were measured in two sediment cores raised from depths of 430 and 700 m within the oxygen-minimum zone (OMZ) off southern Baja California at a temporal resolution of e10.5 kyr over the past 52 kyr. These records are supplemented with diffuse spectral reflectance (DSR) measurements obtained on board ship soon after collection at a resolution of e10.05 kyr. In the core from 700 m depth, a component extracted from the DSR data and the three geochemical proxies generally vary in concert with each other and over a wide range (4-22% orgC; 1-40 mg/kg Cd; 5-120 mg/kg Mo). Intervals of increased orgC, Cd, and Mo accumulation generally correspond to warm periods recorded in the oxygen-isotopic composition of Greenland ice, with the exception of the Bolling/Allerod which is only weakly expressed off Baja California. Concentrations of the biogenic proxies are higher in the core from 430 m depth, but erratic sediment accumulation before 15 ka precludes dating of the older intervals that are laminated and contain elevated orgC, Cd, and Mo concentrations. The new data provide further evidence of an intimate teleconnection between global climate and the intensity of the OMZ and/or productivity along the western margin of North America. On the basis of a comparison with Cd and Mo records collected elsewhere in the region, we conclude that productivity may actually have varied off southern Baja California by no more than a factor of 2 over the past 52 kyr. Copyright 2006 by the American Geophysical Union.

  1. Peculiar ferrimagnetism associated with charge order in layered perovskite GdBaMn2O5.0.

    PubMed

    Taskin, A A; Ando, Yoichi

    2007-05-18

    The magnetic properties of GdBaMn2O5.0, which exhibits charge ordering, are studied from 2 to 400 K using single crystals. In a small magnetic field applied along the easy axis, the magnetization M shows a temperature-induced reversal which is sometimes found in ferrimagnets. In a large magnetic field, on the other hand, a sharp change in the slope of M(T) coming from an unusual turnabout of the magnetization of the Mn sublattices is observed. Those observations are essentially explained by a molecular field theory which highlights the role of delicate magnetic interactions between Gd3+ ions and the antiferromagnetically coupled Mn2+/Mn3+ sublattices.

  2. Systems Analysis Programs for Hands-on Integrated Reliability Evaluations (SAPHIRE) Version 5.0: Data loading manual. Volume 10

    SciTech Connect

    VanHorn, R.L.; Wolfram, L.M.; Fowler, R.D.; Beck, S.T.; Smith, C.L.

    1995-04-01

    The Systems Analysis Programs for Hands-on Integrated Reliability Evaluations (SAPHIRE) suite of programs can be used to organize and standardize in an electronic format information from probabilistic risk assessments or individual plant examinations. The Models and Results Database (MAR-D) program of the SAPHIRE suite serves as the repository for probabilistic risk assessment and individual plant examination data and information. This report demonstrates by examples the common electronic and manual methods used to load these types of data. It is not a stand alone document but references documents that contribute information relative to the data loading process. This document provides a more detailed discussion and instructions for using SAPHIRE 5.0 only when enough information on a specific topic is not provided by another available source.

  3. Modeling of advanced divertor configuration on experimental advanced superconducting tokamak by SOLPS5.0/B2.5-Eirene

    NASA Astrophysics Data System (ADS)

    Si, H.; Guo, H. Y.; Xu, G. S.; Xiao, B. J.; Luo, Z. P.; Guo, Y.; Wang, L.; Ding, R.

    2016-03-01

    Heat exhaust is one of the most challenging issues to be addressed for tokamak magnetic confinement fusion research. Detailed modeling with SOLPS5.0/B2.5-Eirene code package is carried out to examine an alternative advanced divertor configuration, i.e., quasi snowflake (QSF), for long pulse operation in EAST. Comparison is also made with the lower single null (LSN) divertor configuration. SOLPS predicts that the quasi snowflake configuration significantly reduces the peak heat flux at the lower divertor outer target, by a factor of 2-3, owing to the magnetic flux expansion. Furthermore, the density threshold for detachment is much lower for QSF, compared to LSN under the same upstream conditions. This indicates that QSF provides a promising tool for controlling heat flux at divertor target while maintaining a lower separatrix density, which is highly desirable for current drive, thus greatly facilitating long-pulse operation in EAST.

  4. AMDTreat 5.0+ with PHREEQC titration module to compute caustic chemical quantity, effluent quality, and sludge volume

    USGS Publications Warehouse

    Cravotta, Charles A.; Means, Brent P; Arthur, Willam; McKenzie, Robert M; Parkhurst, David L.

    2015-01-01

    Alkaline chemicals are commonly added to discharges from coal mines to increase pH and decrease concentrations of acidity and dissolved aluminum, iron, manganese, and associated metals. The annual cost of chemical treatment depends on the type and quantities of chemicals added and sludge produced. The AMDTreat computer program, initially developed in 2003, is widely used to compute such costs on the basis of the user-specified flow rate and water quality data for the untreated AMD. Although AMDTreat can use results of empirical titration of net-acidic or net-alkaline effluent with caustic chemicals to accurately estimate costs for treatment, such empirical data are rarely available. A titration simulation module using the geochemical program PHREEQC has been incorporated with AMDTreat 5.0+ to improve the capability of AMDTreat to estimate: (1) the quantity and cost of caustic chemicals to attain a target pH, (2) the chemical composition of the treated effluent, and (3) the volume of sludge produced by the treatment. The simulated titration results for selected caustic chemicals (NaOH, CaO, Ca(OH)2, Na2CO3, or NH3) without aeration or with pre-aeration can be compared with or used in place of empirical titration data to estimate chemical quantities, treated effluent composition, sludge volume (precipitated metals plus unreacted chemical), and associated treatment costs. This paper describes the development, evaluation, and potential utilization of the PHREEQC titration module with the new AMDTreat 5.0+ computer program available at http://www.amd.osmre.gov/.

  5. Age-depth model of the past 630 kyr for Lake Ohrid (FYROM/Albania) based on cyclostratigraphic analysis of downhole gamma ray data

    NASA Astrophysics Data System (ADS)

    Baumgarten, H.; Wonik, T.; Tanner, D. C.; Francke, A.; Wagner, B.; Zanchetta, G.; Sulpizio, R.; Giaccio, B.; Nomade, S.

    2015-12-01

    Gamma ray (GR) fluctuations and potassium (K) values from downhole logging data obtained in the sediments of Lake Ohrid from 0 to 240 m below lake floor (b.l.f). correlate with fluctuations in δ18O values from the global benthic isotope stack LR04 (Lisiecki and Raymo, 2005). GR and K values are considered a reliable proxy to depict glacial-interglacial cycles, with high clastic input during cold and/or drier periods and high carbonate precipitation during warm and/or humid periods at Lake Ohrid. Spectral analysis was applied to investigate the climate signal and evolution over the length of the borehole. Linking downhole logging data with orbital cycles was used to estimate sedimentation rates and the effect of compaction was compensated for. Sedimentation rates increase on average by 14 % after decompaction of the sediment layers and the mean sedimentation rates shift from 45 cm kyr-1 between 0 and 110 m to 30 cm kyr-1 from 110 to 240 m b.l.f. Tuning of minima and maxima of gamma ray and potassium values versus LR04 extrema, in combination with eight independent tephrostratigraphical tie points, allows establishing of a robust age model for the downhole logging data over the past 630 kyr.

  6. Mindanao Dome variability over the last 160 kyr: Episodic glacial cooling of the West Pacific Warm Pool

    NASA Astrophysics Data System (ADS)

    Bolliet, Timothé; Holbourn, Ann; Kuhnt, Wolfgang; Laj, Carlo; Kissel, Catherine; Beaufort, Luc; Kienast, Markus; Andersen, Nils; Garbe-Schönberg, Dieter

    2011-02-01

    We present sea surface, upper thermocline, and benthic δ18O data, as well as temperature and paleoproductivity proxy data, from the International Marine Global Change Study Program (IMAGES) Core MD06-3067 (6°31‧N, 126°30‧E, 1575 m water depth), located in the western equatorial Pacific Ocean within the flow path of the Mindanao Current. Our records reveal considerable glacial-interglacial and suborbital variability in the Mindanao Dome upwelling over the last 160 kyr. Dome activity generally intensified during glacial intervals resulting in cooler thermocline waters, whereas it substantially declined during interglacials, in particular in the early Holocene and early marine oxygen isotope stage (MIS) 5e, when upwelling waters did not reach the thermocline. During MIS 3 and MIS 2, enhanced surface productivity together with remarkably low SST and low upper ocean thermal contrast provide evidence for episodic glacial upwelling to the surface, whereas transient surface warming marks periodic collapses of the Mindanao Dome upwelling during Heinrich events. We attribute the high variability during MIS 3 and MIS 2 to changes in the El Niño Southern Oscillation state that affected boreal winter monsoonal winds and upper ocean circulation. Glacial upwelling intensified when a strong cyclonic gyre became established, whereas El Niño-like conditions during Heinrich events tended to suppress the cyclonic circulation, reducing Ekman transport. Thus, our findings demonstrate that variations in the Mindanao Dome upwelling are closely linked to the position and intensity of the tropical convection and also reflect far-field influences from the high latitudes.

  7. Neodymium isotopic evidence for linked changes in Southeast Atlantic and Southwest Pacific circulation over the last 200 kyr

    NASA Astrophysics Data System (ADS)

    Hu, Rong; Noble, Taryn L.; Piotrowski, Alexander M.; McCave, I. Nicholas; Bostock, Helen C.; Neil, Helen L.

    2016-12-01

    Knowledge of the geometry and strength of the deep overturning circulation is central to the understanding of past climate variability on glacial-interglacial (G-I) timescales. In this study, neodymium (Nd) isotopic ratios on planktonic foraminifera are used to reconstruct the water mass source and mixing history of intermediate and deep water in the Southeast (SE) Atlantic and Southwest (SW) Pacific over the past 200 kyr from five sediment cores. Nd isotopes from a depth transect of cores in the SE Atlantic displayed a stronger geochemical gradient around 3.5 km at the LGM, with higher εNd values of ∼-6.0 below that boundary than those of ∼-7.8 above. In contrast, a similar εNd value (∼-9.5) is observed at both the intermediate and abyssal depths in the Holocene. The glacial upper ocean is 1.8 εNd units less radiogenic than the lower ocean, reflecting an increase in the amount of North Atlantic Component Water (NACW) in the upper SE Atlantic. A coherent Nd isotope change was observed in the SE Atlantic and SW Pacific intermediate and deep water with major excursion to more radiogenic εNd values during Marine Isotope Stage (MIS) 2, 4 and 6. This suggests the flux of NACW to the Southern Ocean was reduced during cold marine stages, possibly accompanied by changes in the water mass geometry. The constant 2 εNd-unit offset between intermediate water in the SE Atlantic and SW Pacific suggests the persistent propagation of less radiogenic NACW to the upper Pacific Ocean over the last glacial cycle. Moreover, the larger glacial vertical εNd gradients between the intermediate and deep waters in both the SE Atlantic and SW Pacific indicate a decreased proportion of NACW entrainment into the deep oceans, consistent with studies proposing reduced mixing between the upper and lower meridional overturning cells.

  8. Links between carbonate productivity and ENSO variability in the southern California Current System for the past 2 Kyrs

    NASA Astrophysics Data System (ADS)

    Abella-Gutiérrez, J. L.; Herguera, J. C.

    2014-12-01

    San Lázaro Basin (SLB) is a suboxic basin characteristic for its very high sedimentation rates (1mm/yr) and is located in the dynamic southern boundary of the California Current System (CCS). This southern boundary of the CCS generally extends further south during spring into early summer and retracts towards the north during fall and winter, and this pattern is further amplified or reduced on different time scales, (e.i. interannual timescales by El Niño and La Niña events, or multidecadal ones by the Pacific Decadal Oscillation (PDO)). These oceanographic conditions are related with important differences in the base of the food chain; when the boundary migrates to northern latitudes, the presence of relatively warmer tropical and subtropical waters further stratify the water column, a period when coccolithophorids dominate the microplankton web structure. On the other side, diatoms flourish when the wind-driven circulation expand the subarctic water masses of the CCS to the south and upwelling cells are generated. We find in our cores XRF Ca counts (1 mm resolution) highly correlate with CaCO3 measurements (R=0.56), this last one showing a general decreasing trend over the past 2 Kyrs. The Ca spectrum analysis shows significant peaks for periods centered at 28, 40, 60, 120 yr. The centennial mode of variability of the Ca record shows correlations with Drought area Index from North America. When the variance of this mode is considered, similarities arises with intensity and number of ENSO events from Equatorial archives. Decadal variations of the record are highly correlated (R>0.8) with instrumental measurements of Kaplan sea surface temperature, and the PDO. We will discuss the implications of these periods in the carbonate record and the links between them and other paleoceanographic records in the Pacific.

  9. Geochemical records from loess deposits in Japan over the last 210 kyr: Lithogenic source changes and paleoclimatic indications

    NASA Astrophysics Data System (ADS)

    Miyazaki, Takashi; Kimura, Jun-Ichi; Katakuse, Maiko

    2016-07-01

    The generation, transport, and accumulation of tropospheric dust have changed with the paleoclimatic changes of the Quaternary period. Such dust has accumulated in Japan ˜3000 km leeward of the source deserts in China. We analyzed the fractions of windblown fine quartz and bulk major and trace elements, and Sr-Nd-Pb isotopic compositions of loess in SW Japan deposited over the past 210 kyr. The results indicated extensive accumulation of tropospheric dust mixed with tephra fragments derived from the nearby Daisen volcano. The accumulation rate of fine quartz and selected elemental/isotopic compositions can be used as climatic proxies that reflect greater accumulation of dust in times of colder climate. Chemical indices for weathering show enhanced effects of weathering during times of warmer climate. The trace element compositions of the loess deposits are surprisingly similar to those of the Chinese loess, hemipelagic sediments in the Sea of Japan and the western Pacific Ocean, and the distal Chinese dust found in Canada. This similarity indicates that the loess dust shares major fractions of these fine-grained sediments and that geochemical fractionation during the transport was limited. The Sr-Nd-Pb isotope compositions of the SW Japan loess indicate an origin predominantly in the Gobi Desert. The high-latitude Pacific sediments and high-latitude dust in Canada also show the same signature. However, isotopic compositions of samples from the southern Chinese loess plateau and mid to low-latitude Pacific sediments are largely derived from the Taklimakan desert, which indicates different delivery pathways of the tropospheric dusts.

  10. Changes in the advection of Antarctic Intermediate Water to the northern Chilean coast during the last 970 kyr

    NASA Astrophysics Data System (ADS)

    Martínez-Méndez, G.; Hebbeln, D.; Mohtadi, M.; Lamy, F.; De Pol-Holz, R.; Reyes-Macaya, D.; Freudenthal, T.

    2013-12-01

    Antarctic Intermediate Water (AAIW) is a key player in global-scale oceanic overturning processes and an important conduit for heat, fresh water, and carbon transport. The AAIW past variability is poorly understood mainly due to the lack of sedimentary archives at intermediate water depths. We present records of benthic stable isotopes from sediments retrieved with the seafloor drill rig MARUM-MeBo at 956 m water depth off northern Chile (GeoB15016, 27°29.48'S, 71°07.58'W) that extend back to 970 ka. The sediments at this site are presently deposited at the boundary between AAIW and Pacific Deep Water (PDW). For previous peak interglacials, our results reveal similar benthic δ13C values at site GeoB15016 and of a newly generated stack of benthic δ13C from various deep Pacific cores representing the "average PDW." This suggests, unlike today, the absence of AAIW at the site and the presence of nearly pure PDW. In contrast, more positive δ13C values at site GeoB15016 compared to the stack imply a considerable AAIW contribution during cold phases of interglacials and especially during glacials. Besides, we used three short sediment cores to reconstruct benthic δ13C values from the AAIW core during the last glacial and found a δ13C signature similar to today's. Assuming that this was the case also for the past 970 kyr, we demonstrate that sea level changes and latitudinal migrations of the AAIW formation site can only account for about 50% of the full range of past δ13C increases at site GeoB15016 during cold periods. Other processes that could explain the remaining of the positive δ13C anomalies are increases in glacial AAIW production and/or deeper convection of the AAIW with respect to preceding interglacials.

  11. Variability in the Vertical Structure of the Indonesian Throughflow during the Last 140 kyr: Evidence from the Timor Outflow

    NASA Astrophysics Data System (ADS)

    Xu, J.; Kuhnt, W.; Holbourn, A.; Andersen, N.

    2006-12-01

    We monitored changes in the vertical profile of the Indonesian Throughflow over the last 140 kyr in two sites situated within the Timor outflow: Core SO185-18460 in the Timor Strait and Core MD01-2378 at the southern margin of the outflow path. Centennial records from Core MD01-2378 reveal substantial cooling and freshening of thermocline waters during MIS5e, indicating a change in the vertical structure of the Indonesian Throughflow from surface to thermocline dominated flow. Both surface and thermocline water temperatures initially show an increase of >4°C during Termination II, and tropical sea surface temperature changed synchronously with ice volume (benthic δ18O), implying a direct coupling between high and low latitude climate procesess via atmospheric and/or upper ocean circulation. Comparison of millennial records in Cores SO185- 18460 and MD01-2378, which cover the last two glacial-interglacial cycles, reveals no significant difference in surface temperatures between the two sites, indicating a uniform surface water mass extending from the Timor Strait into the eastern Indian Ocean. In contrast, thermocline water temperatures were approximately 2°C higher in the eastern Indian Ocean during glacials and stadials, implying a decrease in the transport of thermocline waters and a surface water dominated flow during glacials. We speculate that exposure of the Sunda Shelf during sea level lowstands prevented low salinity waters from entering the southern Makassar Strait from the southern South China Sea, as they do in the present day during boreal winters (Gordon et al., 2003). Thus, the modern vertical structure of the Indonesian Throughflow during boreal winters is probably not a realistic analogue for glacial times.

  12. Precessional changes in the western equatorial Pacific Hydroclimate: A 240 kyr marine record from the Halmahera Sea, East Indonesia

    NASA Astrophysics Data System (ADS)

    Dang, Haowen; Jian, Zhimin; Kissel, Catherine; Bassinot, Franck

    2015-01-01

    the precession band, an interhemispheric antiphase pattern in the tropical hydroclimate is supported by many paleorecords, and optimally explained by the forcing of precessional insolation change. However, scenarios within the western equatorial Pacific (WEP), which plays the role of the ascending center of atmospheric convection, remain poorly determined. In this study, a marine sediment core from the Halmahera Sea, East Indonesia, was analyzed with high-resolution XRF scanning, quantitative discrete XRF, and ICP-AES/MS measurements. The terrigenous fractions in this core are constrained by their trace elemental characteristics to be locally sourced from Halmahera Island, and hence reflect variations in the local riverine runoff and precipitation. On this basis, a continuous record of precipitation changes of the western equatorial Pacific was reconstructed with multidecadal resolution over the last ˜240 ka, using an age model established by the correlation between an adjusted ice volume model and benthic δ18O constrained by 14C dating. The records of terrigenous input show a dominant ˜23 kyr periodicity with a 90°˜100° phase lag to the boreal summer (i.e., in-phase with the boreal autumn) insolation change. This pattern can be explained by the variability in the convective activity over the WEP, which might be primarily controlled by precessional changes in the El Niño and Southern Oscillation (ENSO) system. A dynamic linkage is implied between the precessional variations in the convective activity in the WEP and the East Asian and Australia-Indonesian summer monsoons (EASM and AISM), in the sense of their distinct stable phase relationship to precession.

  13. PHYSICAL CHARACTERISTICS OF G331.5-0.1: THE LUMINOUS CENTRAL REGION OF A GIANT MOLECULAR CLOUD

    SciTech Connect

    Merello, Manuel; Bronfman, Leonardo; Garay, Guido; Nyman, Lars-Ake; Evans, Neal J. II; Walmsley, C. Malcolm

    2013-09-01

    We report molecular line and dust continuum observations toward the high-mass star-forming region G331.5-0.1, one of the most luminous regions of massive star formation in the Milky Way, located at the tangent region of the Norma spiral arm, at a distance of 7.5 kpc. Molecular emission was mapped toward the G331.5-0.1 GMC in the CO(J = 1 {yields} 0) and C{sup 18}O(J = 1 {yields} 0) lines with NANTEN, while its central region was mapped in CS(J = 2 {yields} 1 and J = 5 {yields} 4) with SEST, and in CS(J = 7 {yields} 6) and {sup 13}CO(J = 3 {yields} 2) with ASTE. Continuum emission mapped at 1.2 mm with SIMBA and at 0.87 mm with LABOCA reveal the presence of six compact and luminous dust clumps, making this source one of the most densely populated central regions of a GMC in the Galaxy. The dust clumps are associated with molecular gas and they have the following average properties: size of 1.6 pc, mass of 3.2 Multiplication-Sign 10{sup 3} M{sub Sun }, molecular hydrogen density of 3.7 Multiplication-Sign 10{sup 4} cm{sup -3}, dust temperature of 32 K, and integrated luminosity of 5.7 Multiplication-Sign 10{sup 5} L{sub Sun }, consistent with values found toward other massive star-forming dust clumps. The CS and {sup 13}CO spectra show the presence of two velocity components: a high-velocity component at {approx} - 89 km s{sup -1}, seen toward four of the clumps, and a low-velocity component at {approx} - 101 km s{sup -1} seen toward the other two clumps. Radio continuum emission is present toward four of the molecular clumps, with spectral index estimated for two of them of 0.8 {+-} 0.2 and 1.2 {+-} 0.2. A high-velocity molecular outflow is found at the center of the brightest clump, with a line width of 26 km s{sup -1} (FWHM) in CS(J = 7 {yields} 6). Observations of SiO(J = 7 {yields} 6 and J = 8 {yields} 7), and SO(J{sub K} = 8{sub 8} {yields} 7{sub 7} and J{sub K} = 8{sub 7} {yields} 7{sub 6}) lines provide estimates of the gas rotational temperature toward this

  14. Development of the aftershock process of the 2010 Val-des-Bois (Quebec) Mw 5.0 Earthquake

    NASA Astrophysics Data System (ADS)

    Dineva, S.; Steffen, R.; Drysdale, J.; Peci, V.; Fay, E.; McManus, M.

    2011-12-01

    The Mw 5.0 June 23, 2010 earthquake near Val-des-Bois, Quebec (Latitude 45.88N, Longitude 75.48W, depth 22 km) is one of the largest earthquakes in eastern North America since the 2002 Mw 5.0 Au Sable Forks earthquake in upper NY State. The earthquake was felt over an area of approximately 3 million km2 from Quebec, Ontario, and New York State to Maine, Illinois and Kentucky, producing probably the strongest shaking felt in Ottawa, Canada (60 km from the epicentre) in the past 200 years. The maximum intensity of the earthquake was VII MMI. The earthquake produced more than 350 aftershocks in a comparatively small area (~10 x 10 km2) the majority of which occurred within a week. The magnitudes of the recorded aftershocks ranged from 0.7 to 3.3 MN. Within 24 hours after the main shock the Geological Survey of Canada installed 6 temporary stations within 15 km of the epicentre, one of which is still in operation. The records from these stations, as well as the records from the stations of the Canadian National Seismic Network (CNSN), and the POLARIS stations in Ontario and Quebec are used to study the parameters (hypocenter locations and focal mechanisms) of the aftershocks. The hypocenter locations of over 100 events are defined using single event calculations (HYPOCENTER program) and HypoDD. The focal mechanisms are defined for 20 stronger events using P-wave polarities and seismic moment inversion of the waveforms. The depths of 24 aftershocks are defined also using regional depth-phases method. The local stress field is obtained from an inversion of the focal mechanisms using two different methods and compared with the regional stress field. The results from this study show the development of the aftershock process in space and time and the spatial variation of the focal mechanisms. It helped to define the actual fault plane of the main event, as well as to throw some light on the seismotectonics of the epicentral area which is part of the Western Quebec seismic

  15. Nuclear Thermal Rocket/Vehicle Characteristics And Sensitivity Trades For NASA's Mars Design Reference Architecture (DRA) 5.0 Study

    NASA Technical Reports Server (NTRS)

    Borowski, Stanley K.; McCurdy, David R.; Packard, Thomas W.

    2009-01-01

    This paper summarizes Phase I and II analysis results from NASA's recent Mars DRA 5.0 study which re-examined mission, payload and transportation system requirements for a human Mars landing mission in the post-2030 timeframe. Nuclear thermal rocket (NTR) propulsion was again identified as the preferred in-space transportation system over chemical/aerobrake because of its higher specific impulse (I(sub sp)) capability, increased tolerance to payload mass growth and architecture changes, and lower total initial mass in low Earth orbit (IMLEO) which is important for reducing the number of Ares-V heavy lift launches and overall mission cost. DRA 5.0 features a long surface stay (approximately 500 days) split mission using separate cargo and crewed Mars transfer vehicles (MTVs). All vehicles utilize a common core propulsion stage with three 25 klbf composite fuel NERVA-derived NTR engines (T(sub ex) approximately 2650 - 2700 K, p(sub ch) approximately 1000 psia, epsilon approximately 300:1, I(sub sp) approximately 900 - 910 s, engine thrust-toweight ratio approximately 3.43) to perform all primary mission maneuvers. Two cargo flights, utilizing 1-way minimum energy trajectories, pre-deploy a cargo lander to the surface and a habitat lander into a 24-hour elliptical Mars parking orbit where it remains until the arrival of the crewed MTV during the next mission opportunity (approximately 26 months later). The cargo payload elements aerocapture (AC) into Mars orbit and are enclosed within a large triconicshaped aeroshell which functions as payload shroud during launch, then as an aerobrake and thermal protection system during Mars orbit capture and subsequent entry, descent and landing (EDL) on Mars. The all propulsive crewed MTV is a 0-gE vehicle design that utilizes a fast conjunction trajectory that allows approximately 6-7 month 1-way transit times to and from Mars. Four 12.5 kW(sub e) per 125 square meter rectangular photovoltaic arrays provide the crewed MTV with

  16. Phobos spectral clustering: comparison between the 0.5-0.9 micron slope on OMEGA and CRISM data sets

    NASA Astrophysics Data System (ADS)

    Pajola, Maurizio; Roush, Ted L.; Marzo, Giuseppe

    2016-10-01

    We analyzed the MEX-OMEGA (8) and MRO-CRISM (1) visible multispectral data sets of Phobos using I/F values at 0.5 and 0.9 micron and derived spectral slope from these. The purpose is to understand surface spectral variablity on Phobos. Combining the multispectral data sets provides nearly complete coverage for Phobos surface. Different observing scales ranging from 110 to 2000 m/px, with a range of phase angles from 37° to 101°.We applied an unsupervised K-means partitioning algorithm to evaluate the variability of the two I/F values. Each resulting cluster is characterized by an average, and its associated variability. This approach has been validated by application to different Solar System objects, e.g. asteroids, Mars, and Iapetus. The algorithm is agnostic of the physical meaning of the resulting clusters, and scientific interpretation is required for their subsequent evaluation.Using this techinque, 7 clusters were identified for each of the 9 Phobos data sets. For each cluster, we calculated the 0.5-0.9 micron slope within each Phobos data set. The calculated slopes change from a minimum of 0.1% to a maximum of 14.7%. These results indicate that Phobos surface may be more variable than previously suggested, however the exact cause of these variations remains to be determined. In this context, the OMEGA and CRISM data sets are fundamental for expanding our knowledge about Phobos.

  17. Modeling of divertor power footprint widths on EAST by SOLPS5.0/B2.5-Eirene

    NASA Astrophysics Data System (ADS)

    Guozhong, DENG; Xiaoju, LIU; Liang, WANG; Shaocheng, LIU; Jichan, XU; Wei, FENG; Jianbin, LIU; Huan, LIU; Xiang, GAO

    2017-04-01

    The edge plasma code package SOLPS5.0 is employed to simulate the divertor power footprint widths of the experimental advanced superconducting tokamak (EAST) L-mode and ELM-free H-mode plasmas. The divertor power footprint widths, which consist of the scrape-off layer (SOL) width λ q and heat spreading S, are important physical parameters for edge plasmas. In this work, a plasma current scan is implemented in the simulation to obtain the dependence of the divertor power footprint width on the plasma current I p. Strong inverse scaling of the SOL width with I p has been achieved for both L-mode and H-mode plasmas in the forms of {λ }q,{{L}\\text-\\text{mode}}=4.98× {I}{{p}}-0.68 and {λ }q,{{H}\\text-\\text{mode}}=1.86× {I}{{p}}-1.08. Similar trends have also been demonstrated in the study of heat spreading with {S}{{L}\\text-\\text{mode}}=1.95× {I}{{p}}-0.542 and {S}{{H}\\text-\\text{mode}}=0.756× {I}{{p}}-0.872. In addition, studies on divertor peak heat load and the magnetic flux expansion factor show that both of them are proportional to plasma current. The simulation work here can act as a way to explore the power footprint widths of future tokamak fusion devices such as ITER and the China Fusion Engineering Test Reactor (CFETR).

  18. Description of the Mountain Cloud Chemistry Program version of the PLUVIUS MOD 5. 0 reactive storm simulation model

    SciTech Connect

    Luecken, D.J.; Whiteman, C.D.; Chapman, E.G.; Andrews, G.L.; Bader, D.C.

    1987-07-01

    Damage to forest ecosystems on mountains in the eastern United States has prompted a study conducted for the US Environmental Protection Agency's Mountain Cloud Chemistry Program (MCCP). This study has led to the development of a numerical model called MCCP PLUVIUS, which has been used to investigate the chemical transformations and cloud droplet deposition in shallow, nonprecipitating orographic clouds. The MCCP PLUVIUS model was developed as a specialized version of the existing PLUVIUS MOD 5.0 reactive storm model. It is capable of simulating aerosol scavenging, nonreactive gas scavenging, aqueous phase SO/sub 2/ reactions, and cloud water deposition. A description of the new model is provided along with information on model inputs and outputs, as well as suggestions for its further development. The MCCP PLUVIUS incorporates a new method to determine the depth of the layer of air which flows over a mountaintop to produce an orographic cloud event. It provides a new method for calculating hydrogen ion concentrations, and provides updated expressions and values for solubility, dissociation and reaction rate constants.

  19. SDSS J114657.79+403708.6: the third most distant blazar at z = 5.0

    NASA Astrophysics Data System (ADS)

    Ghisellini, G.; Sbarrato, T.; Tagliaferri, G.; Foschini, L.; Tavecchio, F.; Ghirlanda, G.; Braito, V.; Gehrels, N.

    2014-05-01

    The radio-loud quasar SDSS J114657.79+403708.6 at a redshift z = 5.0 is one of the most distant radio-loud objects. The IR-optical luminosity and spectrum suggest that its black hole has a very large mass: M = (5 ± 1) × 109 M⊙. The radio-loudness (ratio of the radio to optical flux) of the source is large (around 100), suggesting that the source is viewed at small angles from the jet axis, and could be a blazar. The X-ray observations fully confirm this hypothesis, due to the high level and hardness of the flux. This makes SDSS J114657.79+403708.6 the third most distant blazar known, after Q0906+693 (z = 5.47) and B2 1023+25 (z = 5.3). Among those, SDSS J114657.79+403708.6 has the largest black hole mass, setting interesting constraints on the mass function of heavy (>109 M⊙) black holes at high redshifts. 971

  20. INTERLINE 5.0 -- An expanded railroad routing model: Program description, methodology, and revised user`s manual

    SciTech Connect

    Johnson, P.E.; Joy, D.S.; Clarke, D.B.; Jacobi, J.M.

    1993-03-01

    A rail routine model, INTERLINE, has been developed at the Oak Ridge National Laboratory to investigate potential routes for transporting radioactive materials. In Version 5.0, the INTERLINE routing algorithms have been enhanced to include the ability to predict alternative routes, barge routes, and population statistics for any route. The INTERLINE railroad network is essentially a computerized rail atlas describing the US railroad system. All rail lines, with the exception of industrial spurs, are included in the network. Inland waterways and deep water routes along with their interchange points with the US railroadsystem are also included. The network contains over 15,000 rail and barge segments (links) and over 13,000 stations, interchange points, ports, and other locations (nodes). The INTERLINE model has been converted to operate on an IBM-compatible personal computer. At least a 286 computer with a hard disk containing approximately 6 MB of free space is recommended. Enhanced program performance will be obtained by using arandom-access memory drive on a 386 or 486 computer.

  1. ITS version 5.0 : the integrated TIGER series of coupled electron/photon Monte Carlo transport codes.

    SciTech Connect

    Franke, Brian Claude; Kensek, Ronald Patrick; Laub, Thomas William

    2004-06-01

    ITS is a powerful and user-friendly software package permitting state of the art Monte Carlo solution of linear time-independent couple electron/photon radiation transport problems, with or without the presence of macroscopic electric and magnetic fields of arbitrary spatial dependence. Our goal has been to simultaneously maximize operational simplicity and physical accuracy. Through a set of preprocessor directives, the user selects one of the many ITS codes. The ease with which the makefile system is applied combines with an input scheme based on order-independent descriptive keywords that makes maximum use of defaults and internal error checking to provide experimentalists and theorists alike with a method for the routine but rigorous solution of sophisticated radiation transport problems. Physical rigor is provided by employing accurate cross sections, sampling distributions, and physical models for describing the production and transport of the electron/photon cascade from 1.0 GeV down to 1.0 keV. The availability of source code permits the more sophisticated user to tailor the codes to specific applications and to extend the capabilities of the codes to more complex applications. Version 5.0, the latest version of ITS, contains (1) improvements to the ITS 3.0 continuous-energy codes, (2)multigroup codes with adjoint transport capabilities, and (3) parallel implementations of all ITS codes. Moreover the general user friendliness of the software has been enhanced through increased internal error checking and improved code portability.

  2. Construction of 144, 565 keV and 5.0 MeV monoenergetic neutron calibration fields at JAERI.

    PubMed

    Tanimura, Y; Yoshizawa, M; Saegusa, J; Fujii, K; Shimizu, S; Yoshida, M; Shibata, Y; Uritani, A; Kudo, K

    2004-01-01

    Monoenergetic neutron calibration fields of 144, 565 keV and 5.0 MeV have been developed at the Facility of Radiation Standards of JAERI using a 4 MV Pelletron accelerator. The 7Li(p,n)7Be and 2H(d,n)3He reactions are employed for neutron production. The neutron energy was measured by the time-of-flight method with a liquid scintillation detector and calculated with the MCNP-ANT code. A long counter is employed as a neutron monitor because of the flat response. The monitor is set up where the influence of inscattered neutrons from devices and their supporting materials at a calibration point is as small as possible. The calibration coefficients from the monitor counts to the neutron fluence at a calibration point were obtained from the reference fluence measured with the transfer instrument of the primary standard laboratory (AIST), a 24.13 cm phi Bonner sphere counter. The traceability of the fields to AIST was established through the calibration.

  3. AGANTG: a Microsoft EXCEL 5.0-visual basic routine for the analysis of dose-response data.

    PubMed

    Zielinski, P J; Buckner, S

    1998-08-01

    A Microsoft EXCEL 5.0 program was developed to evaluate data from biochemical and functional bioassays, an important step in drug discovery. The program accommodates both agonist and antagonist data. The program, written entirely in Visual Basic, is compatible with both Macintosh and PC platforms. Data are conveniently entered into a worksheet following only a few simple rules. The program performs complex data analysis and outputs calculated and graphic results to EXCEL worksheets. A set-up routine with a convenient dialog box offers the user controls regarding data analysis and results formats. After determining if the data are from an agonist or antagonist assay, the program automatically performs the analysis and outputs results in the proper format. Calculations support Schild analysis for antagonists. An agonist and antagonist were analyzed to illustrate program usage and results generated by the analysis. EXCEL-Visual Basic is a useful and convenient tool for evaluating bioassay data. Data entry is greatly simplified and custom reports can be generated with relative ease. Data are stored in a format that allows for easy editing re-analysis.

  4. Fuel-rich catalytic combustion of Jet-A fuel-equivalence ratios 5.0 to 8.0

    NASA Technical Reports Server (NTRS)

    Brabbs, Theodore A.; Gracia-Salcedo, Carmen M.

    1989-01-01

    Fuel-rich catalytic combustion (E.R. greater than 5.0) is a unique technique for preheating a hydrocarbon fuel to temperatures much higher than those obtained by conventional heat exchangers. In addition to producing very reactive molecules, the process upgrades the structure of the fuel by the formation of hydrogen and smaller hydrocarbons and produces a cleaner burning fuel by removing some of the fuel carbon from the soot formation chain. With fuel-rich catalytic combustion as the first stage of a two stage combustion system, enhanced fuel properties can be utilized by both high speed engines, where time for ignition and complete combustion is limited, and engines where emission of thermal NO sub x is critical. Two-stage combustion (rich-lean) has been shown to be effective for NO sub x reduction in stationary burners where residence times are long enough to burn-up the soot formed in the first stage. Such residence times are not available in aircraft engines. Thus, the soot-free nature of the present process is critical for high speed engines. The successful application of fuel-rich catalytic combustion to Jet-A, a multicomponent fuel used in gas turbine combustors, is discusssed.

  5. RegulonDB (version 5.0): Escherichia coli K-12 transcriptional regulatory network, operon organization, and growth conditions

    PubMed Central

    Salgado, Heladia; Gama-Castro, Socorro; Peralta-Gil, Martín; Díaz-Peredo, Edgar; Sánchez-Solano, Fabiola; Santos-Zavaleta, Alberto; Martínez-Flores, Irma; Jiménez-Jacinto, Verónica; Bonavides-Martínez, César; Segura-Salazar, Juan; Martínez-Antonio, Agustino; Collado-Vides, Julio

    2006-01-01

    RegulonDB is the internationally recognized reference database of Escherichia coli K-12 offering curated knowledge of the regulatory network and operon organization. It is currently the largest electronically-encoded database of the regulatory network of any free-living organism. We present here the recently launched RegulonDB version 5.0 radically different in content, interface design and capabilities. Continuous curation of original scientific literature provides the evidence behind every single object and feature. This knowledge is complemented with comprehensive computational predictions across the complete genome. Literature-based and predicted data are clearly distinguished in the database. Starting with this version, RegulonDB public releases are synchronized with those of EcoCyc since our curation supports both databases. The complex biology of regulation is simplified in a navigation scheme based on three major streams: genes, operons and regulons. Regulatory knowledge is directly available in every navigation step. Displays combine graphic and textual information and are organized allowing different levels of detail and biological context. This knowledge is the backbone of an integrated system for the graphic display of the network, graphic and tabular microarray comparisons with curated and predicted objects, as well as predictions across bacterial genomes, and predicted networks of functionally related gene products. Access RegulonDB at . PMID:16381895

  6. NuSTAR Study of Hard X-ray Morphology and Spectroscopy G21.5-0.9

    NASA Technical Reports Server (NTRS)

    Nynka, Melania; Hailey, Charles J.; Reynolds, Stephen P.; An, Hongjun; Baganoff, Frederick K.; Boggs, Steven E.; Christensen, Finn E.; Craig, William W.; Gotthelf, Eric V.; Grefenstette, Brian W.; Harrison, Fiona A.; Krivonos, Roman; Madsen, Kristin K.; Mori, Kaya; Perez, Kerstin; Stern, Daniel; Wik, Daniel R.; Zhang, William W.; Zoglauer, Andreas

    2014-01-01

    We present NuSTAR high-energy X-ray observations of the pulsar wind nebula (PWN)/supernova remnant G21.5-0.9. We detect integrated emission from the nebula up to approx. 40 keV, and resolve individual spatial features over a broad X-ray band for the first time. The morphology seen by NuSTAR agrees well with that seen by XMM-Newton and Chandra below 10 keV. At high energies, NuSTAR clearly detects non-thermal emission up to approx. 20 keV that extends along the eastern and northern rim of the supernova shell. The broadband images clearly demonstrate that X-ray emission from the North Spur and Eastern Limb results predominantly from non-thermal processes. We detect a break in the spatially integrated X-ray spectrum at approx. 9 keV that cannot be reproduced by current spectral energy distribution models, implying either a more complex electron injection spectrum or an additional process such as diffusion compared to what has been considered in previous work. We use spatially resolved maps to derive an energy-dependent cooling length scale, E(sup m) is directly proportional to L(E) with m = -0.21 plus or minus 0.01. We find this to be inconsistent with the model for the morphological evolution with energy described by Kennel & Coroniti. This value, along with the observed steepening in power-law index between radio and X-ray, can be quantitatively explained as an energy-loss spectral break in the simple scaling model of Reynolds, assuming particle advection dominates over diffusion. This interpretation requires a substantial departure from spherical magnetohydrodynamic, magnetic-flux-conserving outflow, most plausibly in the form of turbulent magnetic-field amplification.

  7. Fractal analysis of the galaxy distribution in the redshift range 0.45 ≤ z ≤ 5.0

    NASA Astrophysics Data System (ADS)

    Conde-Saavedra, G.; Iribarrem, A.; Ribeiro, Marcelo B.

    2015-01-01

    This paper performs a fractal analysis of the galaxy distribution and presents evidence that it can be described as a fractal system within the redshift range of the FORS Deep Field (FDF) galaxy survey data. The fractal dimension D was derived by means of the galaxy number densities calculated by Iribarrem et al. (2012) using the FDF luminosity function parameters and absolute magnitudes obtained by Gabasch et al. (2004, 2006) in the spatially homogeneous standard cosmological model with Ωm0 = 0.3, ΩΛ0 = 0.7 and H0 = 70 kms-1Mpc-1. Under the supposition that the galaxy distribution forms a fractal system, the ratio between the differential and integral number densities γ and γ∗ obtained from the red and blue FDF galaxies provides a direct method to estimate D and implies that γ and γ∗ vary as power-laws with the cosmological distances, feature which provides a second method for calculating D. The luminosity distance dL, galaxy area distance dG and redshift distance dz were plotted against their respective number densities to calculate D by linear fitting. It was found that the FDF galaxy distribution is better characterized by two single fractal dimensions at successive distance ranges, that is, two scaling ranges in the fractal dimension. Two straight lines were fitted to the data, whose slopes change at z ≈ 1.3 or z ≈ 1.9 depending on the chosen cosmological distance. The average fractal dimension calculated using γ∗ changes from < D > = 1 .4-0.6+0.7 to < D > = 0 .5-0.4+1.2 for all galaxies. Besides, D evolves with z, decreasing as the redshift increases. Small values of D at high z mean that in the past galaxies and galaxy clusters were distributed much more sparsely and the large-scale structure of the universe was then possibly dominated by voids.

  8. A Compact X-Ray Source in the Radio Pulsar-wind Nebula G141.2+5.0

    NASA Astrophysics Data System (ADS)

    Reynolds, Stephen P.; Borkowski, Kazimierz J.

    2016-01-01

    We report the results of a 50 ks Chandra observation of the recently discovered radio object G141.2+5.0, presumed to be a pulsar-wind nebula. We find a moderately bright unresolved X-ray source that we designate CXOU J033712.8 615302 coincident with the central peak radio emission. An absorbed power-law fit to the 241 counts describes the data well, with absorbing column {N}H=6.7(4.0,9.7)× {10}21 cm-2 and photon index {{Γ }}=1.8(1.4,2.2). For a distance of 4 kpc, the unabsorbed luminosity between 0.5 and 8 keV is {1.7}-0.3+0.4× {10}32 erg s-1 (90% confidence intervals). Both LX and Γ are quite typical of pulsars in PWNe. No extended emission is seen; we estimate a conservative 3σ upper limit to the surface brightness of any X-ray PWN near the point source to be 3× {10}-17 erg cm-2 s-1 arcsec-2 between 0.5 and 8 keV, assuming the same spectrum as the point source; for a nebula of diameter 13\\prime\\prime , the flux limit is 6% of the flux of the point source. The steep radio spectrum of the PWN (α ˜ -0.7), if continued to the X-ray without a break, predicts {L}{{X}} {{(nebula)}}˜ 1× {10}33 erg s-1, so additional spectral steepening between radio and X-rays is required, as is true of all known PWNe. The high Galactic latitude gives a z-distance of 350 pc above the Galactic plane, quite unusual for a Population I object.

  9. Licensing: BP, Lurgi unveil new butanediol process

    SciTech Connect

    Rotman, D.

    1995-07-26

    BP Chemicals and Lurgi (Frankfurt) say they have jointly developed a direct butane-to-1,4-butanediol process and are ready to license the technology. The companies-which began cooperating on the technology in early 1994-say the process, which is being marketed under the name Geminox, promises to be about 40% cheaper to operate than existing butandiol technologies.

  10. South Asian summer monsoon variability during the last ˜54 kyrs inferred from surface water salinity and river runoff proxies

    NASA Astrophysics Data System (ADS)

    Gebregiorgis, D.; Hathorne, E. C.; Sijinkumar, A. V.; Nath, B. Nagender; Nürnberg, D.; Frank, M.

    2016-04-01

    The past variability of the South Asian Monsoon is mostly known from records of wind strength over the Arabian Sea while high-resolution paleorecords from regions of strong monsoon precipitation are still lacking. Here, we present records of past monsoon variability obtained from sediment core SK 168/GC-1, which was collected at the Alcock Seamount complex in the Andaman Sea. We utilize the ecological habitats of different planktic foraminiferal species to reconstruct freshwater-induced stratification based on paired Mg/Ca and δ18O analyses and to estimate seawater δ18O (δ18Osw). The difference between surface and thermocline temperatures (ΔT) and δ18Osw (Δδ18Osw) is used to investigate changes in upper ocean stratification. Additionally, Ba/Ca in G. sacculifer tests is used as a direct proxy for riverine runoff and sea surface salinity (SSS) changes related to monsoon precipitation on land. Our Δδ18Osw time series reveals that upper ocean salinity stratification did not change significantly throughout the last glacial suggesting little influence of NH insolation changes. The strongest increase in temperature gradients between the mixed layer and the thermocline is recorded for the mid-Holocene and indicate the presence of a significantly shallower thermocline. In line with previous work, the δ18Osw and Ba/Ca records demonstrate that monsoon climate during the LGM was characterized by a significantly weaker southwest monsoon circulation and strongly reduced runoff. Based on our data the South Asian Summer Monsoon (SAM) over the Irrawaddyy strengthened gradually after the LGM beginning at ∼18 ka. This is some 3 kyrs before an increase of the Ba/Ca record from the Arabian Sea and indicates that South Asian Monsoon climate dynamics are more complex than the simple N-S displacement of the ITCZ as generally described for other regions. Minimum δ18Osw values recorded during the mid-Holocene are in phase with Ba/Ca marking a stronger monsoon precipitation

  11. H II Region G46.5-0.2: The Interplay between Ionizing Radiation, Molecular Gas, and Star Formation

    NASA Astrophysics Data System (ADS)

    Paron, S.; Ortega, M. E.; Dubner, G.; Yuan, Jing-Hua; Petriella, A.; Giacani, E.; Li, Jin Zeng; Wu, Yuefang; Liu, Hongli; Huang, Ya Fang; Zhang, Si-Ju

    2015-06-01

    H ii regions are particularly interesting because they can generate dense layers of gas and dust, elongated columns or pillars of gas pointing toward the ionizing sources, and cometary globules of dense gas where triggered star formation can occur. Understanding the interplay between the ionizing radiation and the dense surrounding gas is very important to explain the origin of these peculiar structures, and hence to characterize triggered star formation. G46.5-0.2 (G46), a poorly studied galactic H ii region located at about 4 kpc, is an excellent target for performing this kind of study. Using public molecular data extracted from the Galactic Ring Survey (13CO J = 1-0) and from the James Clerk Maxwell Telescope data archive (12CO, 13CO, C18O J = 3-2, HCO+, and HCN J = 4-3), and infrared data from the GLIMPSE and MIPSGAL surveys, we perform a complete study of G46, its molecular environment, and the young stellar objects (YSOs) placed around it. We found that G46, probably excited by an O7V star, is located close to the edge of the GRSMC G046.34-00.21 molecular cloud. It presents a horse-shoe morphology opening in the direction of the cloud. We observed a filamentary structure in the molecular gas likely related to G46 and not considerable molecular emission toward its open border. We found that about 10‧ to the southwest of G46 there are some pillar-like features, shining at 8 μm and pointing toward the H ii region open border. We propose that the pillar-like features were carved and sculpted by the ionizing flux from G46. We found several YSOs likely embedded in the molecular cloud grouped in two main concentrations: one, closer to the G46 open border consisting of Class II type sources, and another mostly composed of Class I type YSOs located just ahead of the pillar-like features, strongly suggesting an age gradient in the YSO distribution.

  12. H ii REGION G46.5-0.2: THE INTERPLAY BETWEEN IONIZING RADIATION, MOLECULAR GAS, AND STAR FORMATION

    SciTech Connect

    Paron, S.; Ortega, M. E.; Dubner, G.; Petriella, A.; Giacani, E.; Yuan, Jing-Hua; Li, Jin Zeng; Liu, Hongli; Huang, Ya Fang; Zhang, Si-Ju; Wu, Yuefang

    2015-06-15

    H ii regions are particularly interesting because they can generate dense layers of gas and dust, elongated columns or pillars of gas pointing toward the ionizing sources, and cometary globules of dense gas where triggered star formation can occur. Understanding the interplay between the ionizing radiation and the dense surrounding gas is very important to explain the origin of these peculiar structures, and hence to characterize triggered star formation. G46.5-0.2 (G46), a poorly studied galactic H ii region located at about 4 kpc, is an excellent target for performing this kind of study. Using public molecular data extracted from the Galactic Ring Survey ({sup 13}CO J = 1–0) and from the James Clerk Maxwell Telescope data archive ({sup 12}CO, {sup 13}CO, C{sup 18}O J = 3–2, HCO{sup +}, and HCN J = 4–3), and infrared data from the GLIMPSE and MIPSGAL surveys, we perform a complete study of G46, its molecular environment, and the young stellar objects (YSOs) placed around it. We found that G46, probably excited by an O7V star, is located close to the edge of the GRSMC G046.34-00.21 molecular cloud. It presents a horse-shoe morphology opening in the direction of the cloud. We observed a filamentary structure in the molecular gas likely related to G46 and not considerable molecular emission toward its open border. We found that about 10′ to the southwest of G46 there are some pillar-like features, shining at 8 μm and pointing toward the H ii region open border. We propose that the pillar-like features were carved and sculpted by the ionizing flux from G46. We found several YSOs likely embedded in the molecular cloud grouped in two main concentrations: one, closer to the G46 open border consisting of Class II type sources, and another mostly composed of Class I type YSOs located just ahead of the pillar-like features, strongly suggesting an age gradient in the YSO distribution.

  13. Asiago spectroscopic classification of ASASSN-16bp

    NASA Astrophysics Data System (ADS)

    Tomasella, L.; Pastorello, A.; Benetti, S.; Cappellaro, E.; Elias-Rosa, N.; Ochner, P.; Tartaglia, L.; Terreran, G.; Turatto, M.

    2016-02-01

    The Asiago Transient Classification Program (Tomasella et al. 2014, AN, 335, 841) reports the spectroscopic classification of ASASSN-16bp ( = AT 2016adq), discovered by All Sky Automated Survey for SuperNovae ASAS-SN (see Shappee et al. 2014, ApJ, 788, 48 and http://www.astronomy.ohio-state.edu/~assassin/index.shtml ), in CGCG 336-041 (Atel #8666) The observation was performed with the Asiago 1.82 m Copernico Telescope (+AFOSC; range 340-820 nm; resolution 1.4 nm). Name | Discovery UT | Obs. Date UT |z | Type | Phase |Notes ASASSN-16bp | 20160209.61 | 20160211.11 |0.034194 | Ia | ~10d | (1) (1) Also known as SN2016adq in CGCG 336-041 (z=0.034194, d=145 Mpc, via NED).

  14. Evidence for a late Holocene warm and humid climate period and environmental characteristics in the arid zones of northwest China during 2.2 ˜ 1.8 kyr B.P.

    NASA Astrophysics Data System (ADS)

    Bao, Yang; Braeuning, Achim; Yafeng, Shi; Fahu, Chen

    2004-01-01

    Natural archives like ice cores, tree rings, river and lake sediments, lake terraces, and paleosols and also historical documents witness aspects of climate change in northwestern China during the Western and Eastern Han Dynasties (206 B.C.-220 A.D.). Reconstructions of decadal averages of annual mean temperature and precipitation fluctuations were derived from variations of δ18O and net accumulation rates in the Guliya ice core. They revealed a period of higher temperatures and higher precipitation than today, which affected vast areas of northwestern China during the period of interest until the fifth century A.D. These conditions resulted in a marked increase in the discharge of big endorheic river systems, such as the Tarim, the Keriya and the Manas rivers. As a consequence, water levels in appendant terminal lakes rose, e.g., at Lop Nor, Manas Lake, and Baijian Hu. Lake surface areas expanded, and lake desalting occurred also at lakes in intermontane basins, such as Balikun Hu and Qinghai Lake. The warm and moist conditions during the Western and Eastern Han Dynasties might have been responsible for the large-scale agricultural production and the local socioeconomic boom that is documented by the occurrence of the famous ruin groups of Loulan, Niya, and Keriya. The following desiccation phase led to a deterioration of water resources, and most oases tended to dry out and were finally abandoned. The appearance, development, flourishing, and final abandonment of each great ruin group are closely associated with regional climate change at that time.

  15. Reconstruction of surface water conditions in the central region of the Okhotsk Sea during the last 180 kyrs

    NASA Astrophysics Data System (ADS)

    Khim, Boo-Keun; Sakamoto, Tatsuhiko; Harada, Naomi

    2012-02-01

    Core GC9A, a 6.7 m long gravity core collected from the central region of the Okhotsk Sea during Cruise YK0712 on R/V Yokosuka (JAMSTEC), was used to reconstruct the changes in surface water conditions by measuring biogenic components (biogenic opal, CaCO3, total organic carbon and δ15N of sediment organic matter) of sediment samples. The age of Core GC9A was determined indirectly by graphic correlation comparing the b* (psychometric yellow-blue chromaticness) values with those of well-dated Core MD01-2415, with complement to the tephra layer (K3; 50 ka). The bottom age of Core GC9A was estimated to be about 180 kyr; therefore it provides the history of surface water conditions from MIS 1 to MIS 6. The biogenic opal, CaCO3, and TOC contents were high during the interglacial periods as expected, indicating enhanced surface water production under warm climatic conditions. This condition resulted from sufficient nutrient supply to the surface waters by active vertical mixing, which was validated by low δ15N values of the sediment organic matter. In contrast, surface water productivity was depressed during the colder glacial periods, probably due to the expanded sea-ice distribution and limited nutrient supply. However, the glacial sediments had moderately high δ15N values, indicating enhanced nitrate utilization resulting from the limited nutrient supply caused by strong stratification of the surface water. High δ15N values were also observed during the deglaciation, which was attributed to the increased nitrate utilization during enhanced surface water productivity. However, the low δ15N values during the glacial and deglacial periods may be attributed to the increased supply of terrestrial organic matter. Diatom production was primarily responsible for surface water paleoproductivity during the interglacial periods rather than coccolithophores. However, the succession of glacial to early deglacial coccolithophore production and late deglacial to interglacial

  16. Man the Fat Hunter: The Demise of Homo erectus and the Emergence of a New Hominin Lineage in the Middle Pleistocene (ca. 400 kyr) Levant

    PubMed Central

    Ben-Dor, Miki; Gopher, Avi; Hershkovitz, Israel; Barkai, Ran

    2011-01-01

    The worldwide association of H. erectus with elephants is well documented and so is the preference of humans for fat as a source of energy. We show that rather than a matter of preference, H. erectus in the Levant was dependent on both elephants and fat for his survival. The disappearance of elephants from the Levant some 400 kyr ago coincides with the appearance of a new and innovative local cultural complex – the Levantine Acheulo-Yabrudian and, as is evident from teeth recently found in the Acheulo-Yabrudian 400-200 kyr site of Qesem Cave, the replacement of H. erectus by a new hominin. We employ a bio-energetic model to present a hypothesis that the disappearance of the elephants, which created a need to hunt an increased number of smaller and faster animals while maintaining an adequate fat content in the diet, was the evolutionary drive behind the emergence of the lighter, more agile, and cognitively capable hominins. Qesem Cave thus provides a rare opportunity to study the mechanisms that underlie the emergence of our post-erectus ancestors, the fat hunters. PMID:22174868

  17. Bulk and Compound-Specific Isotope Analysis of Long-Chain, n-alkanes From a 85-kyr Core From Lake Peten Itza, Guatemala

    NASA Astrophysics Data System (ADS)

    Mays, J. L.; Brenner, M.; Bush, M. B.; Correa, A.; Curtis, J. H.; Hodell, D. A.

    2007-12-01

    Drill cores obtained from Lake Petén Itzá, Guatemala, contain a ~85-kyr record of terrestrial climate from lowland Central America. Variations in sediment lithology suggest rapid changes in precipitation during the last glacial and deglacial periods. Previous work in nearby Lake Quexil demonstrated the utility of using the carbon isotopic compositions of leaf wax n-alkanes to infer changes in terrestrial vegetation (Huang et al., 2001). Here we report carbon isotopes of bulk organic and long-chain n-alkanes in 60 samples to reconstruct changes in the relative proportion of C3 and C4 biomass in the watershed under changing climate and atmospheric CO2 conditions during the past 85 kyrs. Compound-specific carbon isotope results are compared directly with pollen analysis from the same samples. Huang, Y., F.A. Street-Perrott, S.E. Metcalfe, M. Brenner, M. Moreland, and K.H. Freeman. 2001. Climate change as the dominant control on glacial-interglacial variations in C3 and C4 plant abundance. Science 293:1647-1651.

  18. An 80 kyr-long continuous speleothem record from Dim Cave, SW Turkey with paleoclimatic implications for the Eastern Mediterranean

    PubMed Central

    Ünal-İmer, Ezgi; Shulmeister, James; Zhao, Jian-Xin; Tonguç Uysal, I.; Feng, Yue-Xing; Duc Nguyen, Ai; Yüce, Galip

    2015-01-01

    Speleothem-based stable isotope records are valuable in sub-humid and semi-arid settings where many other terrestrial climate proxies are fragmentary. The Eastern Mediterranean is one such region. Here we present an 80-kyr-long precisely-dated (by U-series) and high-resolution oxygen (δ18O) and carbon (δ13C) records from Dim Cave (~36°N) in SW Turkey. The glacial-interglacial δ18O variations in the Dim Cave speleothem are best explained in terms of changes in the trajectories of winter westerly air masses. These are along a northerly (European) track (isotopically less depleted) during the early last glaciation but are gradually depressed southward closer to the modern westerly track along the North African coast (more depleted) after c.50 kyr and remain in the southern track through the Last Glacial Maximum. The southward displacement of the westerly track reflects growth of the Fennoscandian ice sheet and its impact on westerly wind fields. Changes in δ13C are interpreted as reflecting soil organic matter composition and/or thickness. δ13C values are significantly more negative in interglacials reflecting active carbonic acid production in the soil and less negative in glacial times reflecting carbonate rock values. Several Heinrich events are recorded in the Dim record indicating intensification of westerly flow across this part of the EM. PMID:26337921

  19. Biogeochemistry of mineral-organic associations across a long-term mineralogical soil gradient (0.3-4100 kyr), Hawaiian Islands

    NASA Astrophysics Data System (ADS)

    Mikutta, Robert; Schaumann, Gabriele E.; Gildemeister, Daniela; Bonneville, Steeve; Kramer, Marc G.; Chorover, Jon; Chadwick, Oliver A.; Guggenberger, Georg

    2009-04-01

    Organic matter (OM) in mineral-organic associations (MOAs) represents a large fraction of carbon in terrestrial ecosystems which is considered stable against biodegradation. To assess the role of MOAs in carbon cycling, there is a need to better understand (i) the time-dependent biogeochemical evolution of MOAs in soil, (ii) the effect of the mineral composition on the physico-chemical properties of attached OM, and (iii) the resulting consequences for the stabilization of OM. We studied the development of MOAs across a mineralogical soil gradient (0.3-4100 kyr) at the Hawaiian Islands that derived from basaltic tephra under comparable climatic and hydrological regimes. Mineral-organic associations were characterized using biomarker analyses of OM with chemolytic methods (lignin phenols, non-cellulosic carbohydrates) and wet chemical extractions, surface area/porosity measurements (N 2 at 77 K and CO 2 at 273 K), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and differential scanning calorimetry (DSC). The results show that in the initial weathering stage (0.3 kyr), MOAs are mainly composed of primary, low-surface area minerals (olivine, pyroxene, feldspar) with small amounts of attached OM and lignin phenols but a large contribution of microbial-derived carbohydrates. As high-surface area, poorly crystalline (PC) minerals increase in abundance during the second weathering stage (20-400 kyr), the content of mineral-associated OM increased sharply, up to 290 mg C/g MOA, with lignin phenols being favored over carbohydrates in the association with minerals. In the third and final weathering stage (1400-4100 kyr), metastable PC phases transformed into well crystalline secondary Fe and Al (hydr)oxides and kaolin minerals that were associated with less OM overall, and depleted in both lignin and carbohydrate as a fraction of total OM. XPS, the N 2 pore volume data and OM-mineral volumetric ratios suggest that, in contrast to the

  20. Centennial- to millennial-scale ice-ocean interactions in the subpolar northeast Atlantic 18-41 kyr ago

    NASA Astrophysics Data System (ADS)

    Hall, I. R.; Colmenero-Hidalgo, E.; Zahn, R.; Peck, V. L.; Hemming, S. R.

    2011-06-01

    In order to monitor the evolution of the British-Irish Ice Sheet (BIIS) and its influence in surface ocean structure during marine isotopic stages (MIS) 2 and 3, we have analyzed the sediments recovered in core MD04-2829CQ (Rosemary Bank, north Rockall Trough, northeast Atlantic) dated between ˜41 and ˜18 ka B.P. Ice-rafted debris flux and composition, 40Ar/39Ar ages of individual hornblende grains, multispecies planktonic stable isotope records, planktonic foraminifera assemblage data and faunal-based sea surface temperatures (SSTs) demonstrate a close interaction between BIIS dynamics and surface ocean structure and water properties in this region. The core location lies beneath the North Atlantic Current (NAC) and is ideal for monitoring the shifts in the position of its associated oceanic fronts, as recorded by faunal changes. These data reveal a succession of BIIS-sourced iceberg calving events related to low SST, usually synchronous with dramatic changes in the composition of the planktonic foraminifera assemblage and with variations in the stable isotope records of the taxa Neogloboquadrina pachyderma (sinistral coiling) and Globigerina bulloides. The pacing of the calving events, from typically Dansgaard-Oeschger millennial timescales during late MIS 3 to multicentennial cyclicity from ˜28 ka B.P., represents the build-up of the BIIS and its growing instability toward Heinrich Event (HE) 2 and the Last Glacial Maximum. Our data confirm the strong coupling between BIIS instabilities and the temperature and salinity of surface waters in the adjacent northeast Atlantic and demonstrate the BIIS's ability to modify the NAC on its flow toward the Nordic Seas. In contrast, subsurface water masses were less affected except during the Greenland stadials that contain HEs, when most intense water column reorganizations occurred simultaneously with the deposition of cream-colored carbonate sourced from the Laurentide Ice Sheet.

  1. Ambulatory BP monitoring and clinic BP in predicting small-for-gestational-age infants during pregnancy.

    PubMed

    Eguchi, K; Ohmaru, T; Ohkuchi, A; Hirashima, C; Takahashi, K; Suzuki, H; Kario, K; Matsubara, S; Suzuki, Mitsuaki

    2016-01-01

    The significance of ambulatory blood pressure (ABP) monitoring during pregnancy has not been established. We performed a prospective study to elucidate whether ABP measures are associated with small-for-gestational-age birth weight (SGA). We studied 146 pregnant women who were seen for maternal medical checkups or suspected hypertension. ABP monitoring was performed for further assessment of hypertension. The outcome measure was SGA. The subjects were classified by their medical history and ABP as having preeclampsia or gestational hypertension (n=68 cases), chronic hypertension (n=48) or white-coat hypertension (n=30). There were 50 (34.2%) cases of SGA by the fetal growth reference standard. In multivariable logistic regression analyses adjusting for age, body mass index, the presence of prior pregnancy, current smoking habit and the use of antihypertensive medications, 24-h SBP (per 10 mm Hg (odds ratio (OR): 1.74; 95% confidence interval (CI): 1.28-2.38; P<0.001)) was more closely associated with SGA than clinic BP (OR: 1.40; 95% CI: 0.92-2.13; P=0.11). The results were essentially the same if 24-h BP was replaced by awake or sleep SBP. Ambulatory diastolic BP showed the same tendency. However, abnormal circadian rhythm was not associated with the outcome. In conclusion, ambulatory BP monitoring measures performed during pregnancy were more closely associated with SGA than clinic BP.

  2. Deficiency in Either 4E-BP1 or 4E-BP2 Augments Innate Antiviral Immune Responses

    PubMed Central

    Nehdi, Atef; Sean, Polen; Linares, Izzar; Colina, Rodney; Jaramillo, Maritza; Alain, Tommy

    2014-01-01

    Genetic deletion of both 4E-BP1 and 4E-BP2 was found to protect cells against viral infections. Here we demonstrate that the individual loss of either 4E-BP1 or 4E-BP2 in mouse embryonic fibroblasts (MEFs) is sufficient to confer viral resistance. shRNA-mediated silencing of 4E-BP1 or 4E-BP2 renders MEFs resistant to viruses, and compared to wild type cells, MEFs knockout for either 4E-BP1 or 4E-BP2 exhibit enhanced translation of Irf-7 and consequently increased innate immune response to viruses. Accordingly, the replication of vesicular stomatitis virus, encephalomyocarditis virus, influenza virus and Sindbis virus is markedly suppressed in these cells. Importantly, expression of either 4E-BP1 or 4E-BP2 in double knockout or respective single knockout cells diminishes their resistance to viral infection. Our data show that loss of 4E-BP1 or 4E-BP2 potentiates innate antiviral immunity. These results provide further evidence for translational control of innate immunity and support targeting translational effectors as an antiviral strategy. PMID:25531441

  3. T4-like phage Bp7, a potential antimicrobial agent for controlling drug-resistant Escherichia coli in chickens.

    PubMed

    Zhang, Can; Li, Wenli; Liu, Wenhua; Zou, Ling; Yan, Chen; Lu, Kai; Ren, Huiying

    2013-09-01

    Chicken-pathogenic Escherichia coli is severely endangering the poultry industry in China and worldwide, and antibiotic therapy is facing an increasing problem of antibiotic resistance. Bacteriophages can kill bacteria with no known activity in human or animal cells, making them an attractive alternative to antibiotics. In this study, we present the characteristics of a novel virulent bacteriophage, Bp7, specifically infecting pathogenic multidrug-resistant E. coli. Phage Bp7 was isolated from chicken feces. Bp7 belongs to the family Myoviridae, possessing an elongated icosahedral head and contractile sheathed tail. It has a 168-kb double-stranded DNA genome. For larger yields, its optimal multiplicity of infection (MOI) to infect E. coli was about 0.001. The latent period was 10 to 15 min, and the burst size was 90 PFU/infected cell. It was stable both at pH 5.0 to 10.0 and at 40°C or 50°C for at least 1 h. Bp7 could infect 46% of pathogenic clinical E. coli strains. Bp7 harbored 791 open reading frames (ORFs) and 263 possible genes. Among the 263 genes, 199 possessed amino acid sequence identities with ORFs of phage T4, 62 had identities with other T4-like phages, and only one lacked any database match. The genome of Bp7 manifested obvious division and rearrangement compared to phages T4, JS98, and IME08. Bp7 is a new member of the "T4-like" genus, family Myoviridae. Its wide host range, strong cell-killing activity, and high stability to pH make it an alternative to antimicrobials for controlling drug-resistant E. coli in chickens.

  4. The stability and electronic structures of Si/O/Al/P atom doped (5,0)boron nitrogen nanotubes with Stone-Wales defects: Density functional theory studies

    NASA Astrophysics Data System (ADS)

    Li, KeJing; Ye, JinQian; Zhang, Juan; Wang, XiYuan; Shao, QingYi

    2017-03-01

    Using density functional theory, we have investigated Si/O/Al/P atoms doped (5,0)BNNTs with SW defects. We have mainly found that Si/O/Al/P have improved the stability of (5,0)BNNTs with SW defects. In view of Mulliken charge, we have thought Si/O/Al/P atoms have donated electrons (charge +e state or charge -e state) to nanotubes, contributing BNNTs with SW defects to stable. Meanwhile, from the aspect of energy band structure and DOS, we have further explained the reason. We have considerred that stability of doped structures has related to hybridization between doped atom and BNNTs. The stability has changed with changing the degree of hybridization. Moreover, B atom can play a crucial role in the insertion of Si/O/Al/P atom into (5,0)BNNTs with SW defects.

  5. 200 kyrs of sediment deposition in the coastal lowlands of Bol'shoy Lyakhovsky - a record of deglaciation of the New Siberian Islands?

    NASA Astrophysics Data System (ADS)

    Schwamborn, Georg; Schirrmeister, Lutz; Wetterich, Sebastian; Fuchs, Margret; Meyer, Hanno; Siegert, Christine

    2016-04-01

    Bol'shoy Lyakhovsky, the southernmost island of the New Siberian Archipelago, holds the longest record of palaeoenvironmental history in the North Siberian Arctic. It stretches back to ~200 kyr before present. Next to palaeosols and floodplain deposits it includes prominent thermokarst deposits from the Last Interglacial and Yedoma (Ice Complex) sections from the Last Glacial. Yet, it is unknown, whether or not the depositional history of the area is affected by the deglaciation of the northern part of the New Siberian Archipelago. Potentially, it could give insights into the break-up of the proposed MIS 6 ice sheet located on the East Siberian Sea shelf. Polymodal particle size distributions in the sediment record suggest that more than one transport mechanism drove sediment accumulation from more than one source. From a cryo-sedimentological data set we focus on the mineral composition (63-125 μm fraction) to determine the provenance of the deposits and to identify possible changes of transport pathways. Complementary, we use pore ice hydrochemical data to track changes of the weathering solution preserved in permafrost. Presumably, the both complement each other, since the weathering products largely depend on the mineral composition. We conclude that the observed trends in the heavy mineral and pore ice chemical data of the frozen ground record reflect short-distance material transport from weathered bedrock to the depositional area. In this sense no portion of the 200 kyr record seems to be affected by the presumed MIS 6 ice sheet break-up, which at that time happened about 250 km north of the study site.

  6. Development of coccolithophore-based transfer functions in the Western Mediterranean Sea: a sea surface salinity reconstruction for the last 15.5 kyr

    NASA Astrophysics Data System (ADS)

    Ausín, B.; Hernández-Almeida, I.; Flores, J.-A.; Sierro, F.-J.; Grosjean, M.; Francés, G.; Alonso, B.

    2015-08-01

    A new dataset of 88 marine surface sediment samples and related oceanic environmental variables (temperature, salinity, chlorophyll a, oxygen, etc.) was studied to quantify the relationship between assemblages of coccolithophore species and modern environmental conditions in the Western Mediterranean Sea and the Atlantic Ocean, west of the Strait of Gibraltar. Multivariate statistical analyses revealed that coccolithophore species were primarily related to the sea surface salinity (SSS) gradient, which explains an independent and significant proportion of variance in the coccolithophore data. A quantitative coccolithophore-based transfer function to estimate SSS was developed using the Modern Analog Technique (MAT) and weighted-averaging partial-least square regression (WA-PLS). The bootstrapped regression coefficient (R2boot) was 0.85MAT and 0.80WA-PLS, with root-mean square error of prediction (RMSEP) of 0.29MAT and 0.30WA-PLS (psu). The resulting transfer function was applied to fossil coccolithophore assemblages in the highly resolved (∼ 65 yr) sediment core CEUTA10PC08 from the Alboran Sea (Western Mediterranean) in order to reconstruct SSS for the last 25 kyr. The reliability of the reconstruction was evaluated by assessing the degree of similarity between fossil and modern coccolithophore assemblage, and comparison of reconstruction with fossil ordination scores. Analogs were poor for the stadials associated with Heinrich Event 2 and 1 and part of the Last Glacial Maximum. Good analogs indicate more reliable reconstruction of the SSS for the last 15.5 kyr. During this period, several millennial and centennial SSS changes were observed and associated with variations in the Atlantic Water entering the Alboran Sea, sea-level oscillations, and arid or humid atmospheric conditions in the Western Mediterranean.

  7. Development of coccolithophore-based transfer functions in the western Mediterranean sea: a sea surface salinity reconstruction for the last 15.5 kyr

    NASA Astrophysics Data System (ADS)

    Ausín, B.; Hernández-Almeida, I.; Flores, J.-A.; Sierro, F.-J.; Grosjean, M.; Francés, G.; Alonso, B.

    2015-12-01

    A new data set of 88 marine surface sediment samples and related oceanic environmental variables (temperature, salinity, chlorophyll a, oxygen, etc.) was studied to quantify the relationship between assemblages of coccolithophore species and modern environmental conditions in the western Mediterranean Sea and the Atlantic Ocean, west of the Strait of Gibraltar. Multivariate statistical analyses revealed that coccolithophore species were primarily related to sea surface salinity (SSS), explaining an independent and significant proportion of variance in the coccolithophore data. A quantitative coccolithophore-based transfer function to estimate SSS was developed using the modern analog technique (MAT) and weighted-averaging partial least square regression (WA-PLS). The bootstrapped regression coefficient (R2boot) was 0.85MAT and 0.80WA-PLS, with a root-mean-square error of prediction (RMSEP) of 0.29MAT and 0.30WA-PLS (psu). The resulting transfer function was applied to fossil coccolithophore assemblages in the highly resolved (~ 65 years) sediment core CEUTA10PC08 from the Alboran Sea (western Mediterranean) in order to reconstruct SSS for the last 25 kyr. The reliability of the reconstruction was evaluated by assessing the degree of similarity between fossil and modern coccolithophore assemblages and by a comparison of reconstructions with fossil ordination scores. Analogs were poor for the stadials associated with Heinrich events 2 and 1 and part of the Last Glacial Maximum. Good analogs indicate a more reliable reconstruction of the SSS for the last 15.5 kyr. During this period, several millennial and centennial SSS changes were observed and associated with sea-level oscillations and variations in the Atlantic Water entering the Alboran.

  8. BP Spill Sampling and Monitoring Data

    EPA Pesticide Factsheets

    This dataset analyzes waste from the the British Petroleum Deepwater Horizon Rig Explosion Emergency Response, providing opportunity to query data sets by metadata criteria and find resulting raw datasets in CSV format.The data query tool allows users to download EPA's air, water and sediment sampling and monitoring data that has been collected in response to the BP oil spill. All sampling and monitoring data that has been collected to date is available for download as raw structured data.The query tools enables CSV file creation to be refined based on the following search criteria: date range (between April 28, 2010 and 9/29/2010); location by zip, city, or county; media (solid waste, weathered oil, air, surface water, liquid waste, tar, sediment, water); substance categories (based on media selection) and substances (based on substance category selection).

  9. Systems analysis programs for Hands-on integrated reliability evaluations (SAPHIRE) Version 5.0: Verification and validation (V&V) manual. Volume 9

    SciTech Connect

    Jones, J.L.; Calley, M.B.; Capps, E.L.; Zeigler, S.L.; Galyean, W.J.; Novack, S.D.; Smith, C.L.; Wolfram, L.M.

    1995-03-01

    A verification and validation (V&V) process has been performed for the System Analysis Programs for Hands-on Integrated Reliability Evaluation (SAPHIRE) Version 5.0. SAPHIRE is a set of four computer programs that NRC developed for performing probabilistic risk assessments. They allow an analyst to perform many of the functions necessary to create, quantify, and evaluate the risk associated with a facility or process being analyzed. The programs are Integrated Reliability and Risk Analysis System (IRRAS) System Analysis and Risk Assessment (SARA), Models And Results Database (MAR-D), and Fault tree, Event tree, and Piping and instrumentation diagram (FEP) graphical editor. Intent of this program is to perform a V&V of successive versions of SAPHIRE. Previous efforts have been the V&V of SAPHIRE Version 4.0. The SAPHIRE 5.0 V&V plan is based on the SAPHIRE 4.0 V&V plan with revisions to incorporate lessons learned from the previous effort. Also, the SAPHIRE 5.0 vital and nonvital test procedures are based on the test procedures from SAPHIRE 4.0 with revisions to include the new SAPHIRE 5.0 features as well as to incorporate lessons learned from the previous effort. Most results from the testing were acceptable; however, some discrepancies between expected code operation and actual code operation were identified. Modifications made to SAPHIRE are identified.

  10. “Dynamic evaluation of the CMAQv5.0 modeling system: Assessing the model’s ability to simulate ozone changes due to NOx emission reductions”

    EPA Science Inventory

    Dynamic evaluation of the CMAQv5.0 modeling system during the NOx SIP Call time period indicates that the model underestimates the observed ozone decrease in eastern U.S. Utilizing novel cross simulations we are able to separately quantify the impact on ozone predictions stemmin...

  11. SAS2H input for computing core activities of 4.5, 5.0, and 5.5 weight % {sup 235}U fuel for Sequoyah Nuclear Plant

    SciTech Connect

    Hermann, O.W.

    1994-08-01

    Sequoyah Nuclear Plant core activities at initial fuel enrichments of 4.5, 5.0, and 5.5 wt% {sup 235}U, required in nuclear safety evaluations, were computed by the SAS2H analysis sequence and the ORIGEN-S code within the SCALE-4.2 code system.

  12. Chemical characteristics of PM2.5-0.3 and PM0.3 and consequence of a dust storm episode at an urban site in Lebanon

    NASA Astrophysics Data System (ADS)

    Borgie, Mireille; Ledoux, Frédéric; Dagher, Zeina; Verdin, Anthony; Cazier, Fabrice; Courcot, Lucie; Shirali, Pirouz; Greige-Gerges, Hélène; Courcot, Dominique

    2016-11-01

    Located on the eastern side of the Mediterranean Basin at the intersection of air masses circulating between three continents, the agglomeration of Beirut, capital of Lebanon is an important investigating area for air pollution and more studies are needed to elucidate the composition of the smallest particles classified as carcinogenic to humans. PM2.5-0.3 and PM0.3 samples were collected during the spring-summer period in an urban background site of Beirut, after a dust storm episode occurred, and their chemical composition was determined. Our findings showed that components formed by gas to particle conversion (SO42 - and NH4+) and related to combustion processes are mainly found in the PM0.3 fraction. Typical crustal (Ca2+, Fe, Ti, Mg2+), sea-salt (Na+, Cl-, Mg2+, Sr) species, and NO3- are mainly associated with the PM2.5-0.3 fraction. We have also evidenced that the dust episode which occurred in Lebanon in May 2011 originated from the Iraqian and Syrian deserts, which are the least studied, and had a direct influence on the composition of PM2.5-0.3 during the beginning of the first sampling period, and then an indirect and persistent influence by the re-suspension of deposited dust particles. Moreover, PAHs concentrations were much higher in PM0.3 than in PM2.5-0.3 and their composition appeared influenced by diesel (buses, trucks and generator sets) and gasoline (private cars) emissions.

  13. Waste Sampling Data for BP Spill/Deepwater Horizon

    EPA Pesticide Factsheets

    The Deepwater Horizon oil spill (also referred to as the BP oil spill) began on 20 April 2010 in the Gulf of Mexico on the BP-operated Macondo Prospect. Following the explosion and sinking of the Deepwater Horizon oil rig, a sea-floor oil gusher flowed for 87 days, until it was capped on 15 July 2010.In response to the BP oil spill, EPA sampled air, water, sediment, and waste generated by the cleanup operations.

  14. Air Sampling Data for BP Spill/Deepwater Horizon

    EPA Pesticide Factsheets

    The Deepwater Horizon oil spill (also referred to as the BP oil spill) began on 20 April 2010 in the Gulf of Mexico on the BP-operated Macondo Prospect. Following the explosion and sinking of the Deepwater Horizon oil rig, a sea-floor oil gusher flowed for 87 days, until it was capped on 15 July 2010.In response to the BP oil spill, EPA sampled air, water, sediment, and waste generated by the cleanup operations.

  15. Air Monitoring Data for BP Spill/Deepwater Horizon

    EPA Pesticide Factsheets

    The Deepwater Horizon oil spill (also referred to as the BP oil spill) began on 20 April 2010 in the Gulf of Mexico on the BP-operated Macondo Prospect. Following the explosion and sinking of the Deepwater Horizon oil rig, a sea-floor oil gusher flowed for 87 days, until it was capped on 15 July 2010.In response to the BP oil spill, EPA sampled air, water, sediment, and waste generated by the cleanup operations.

  16. Surface Water Sampling Data for BP Spill/Deepwater Horizon

    EPA Pesticide Factsheets

    The Deepwater Horizon oil spill (also referred to as the BP oil spill) began on 20 April 2010 in the Gulf of Mexico on the BP-operated Macondo Prospect. Following the explosion and sinking of the Deepwater Horizon oil rig, a sea-floor oil gusher flowed for 87 days, until it was capped on 15 July 2010.In response to the BP oil spill, EPA sampled air, water, sediment, and waste generated by the cleanup operations.

  17. Sediment Sampling Data for BP Spill/Deepwater Horizon

    EPA Pesticide Factsheets

    The Deepwater Horizon oil spill (also referred to as the BP oil spill) began on 20 April 2010 in the Gulf of Mexico on the BP-operated Macondo Prospect. Following the explosion and sinking of the Deepwater Horizon oil rig, a sea-floor oil gusher flowed for 87 days, until it was capped on 15 July 2010.In response to the BP oil spill, EPA sampled air, water, sediment, and waste generated by the cleanup operations.

  18. Water Sampling Data for BP Spill/Deepwater Horizon

    EPA Pesticide Factsheets

    The Deepwater Horizon oil spill (also referred to as the BP oil spill) began on 20 April 2010 in the Gulf of Mexico on the BP-operated Macondo Prospect. Following the explosion and sinking of the Deepwater Horizon oil rig, a sea-floor oil gusher flowed for 87 days, until it was capped on 15 July 2010.In response to the BP oil spill, EPA sampled air, water, sediment, and waste generated by the cleanup operations.

  19. Temperature Evolution of Physical Properties of BaTi0.9(Nb0.5Yb0.5)0.1O3 Lead-Free Ceramic

    NASA Astrophysics Data System (ADS)

    Abdelkafi, Z.; Abdelmoula, N.; Khemakhem, H.

    2016-11-01

    BaTi0.9(Nb0.5Yb0.5)0.1O3 lead-free ceramic was prepared by a solid-state reaction method. The structure of BaTi0.9(Nb0.5Yb0.5)0.1O3 has been characterized by means of x-ray diffraction, showing the coexistence of cubic (31.1%) and tetragonal (68.9%) phases at room temperature. Dielectric spectroscopy shows that BaTi0.9(Nb0.5Yb0.5)0.1O3 composition sintered at 1380°C exhibits a relaxor behavior with a weak diffuse phase transition obeying a Lorentz-type quadratic relationship. The ferroelectric-paraelectric phase transition T C decreased from 420 K for BaTiO3 to 284 K for BaTi0.9(Nb0.5Yb0.5)0.1O3. The dielectric loss of this ceramic was <0.09 over a wide temperature range (<400 K). The temperature behavior of the main piezoelectric parameters, such as the piezoelectric coefficient d 31 and the electromechanical coupling factor k p, was investigated. d 31 sets a maximum about 32.5 pC/N at temperature of 220 K. Nevertheless, k p undergoes more or less important changes between 120 K and 200 K. Over 200 K, k p degrades very rapidly due to the depoling effect deduced from the hysterisis measurements. Dielectric and structural properties of BaTi0.9(Nb0.5Yb0.5)0.1O3 were confirmed by Raman spectroscopy.

  20. Peptide binding to HLA-DP proteins at pH 5.0 and pH 7.0: a quantitative molecular docking study

    PubMed Central

    2012-01-01

    Background HLA-DPs are class II MHC proteins mediating immune responses to many diseases. Peptides bind MHC class II proteins in the acidic environment within endosomes. Acidic pH markedly elevates association rate constants but dissociation rates are almost unchanged in the pH range 5.0 – 7.0. This pH-driven effect can be explained by the protonation/deprotonation states of Histidine, whose imidazole has a pKa of 6.0. At pH 5.0, imidazole ring is protonated, making Histidine positively charged and very hydrophilic, while at pH 7.0 imidazole is unprotonated, making Histidine less hydrophilic. We develop here a method to predict peptide binding to the four most frequent HLA-DP proteins: DP1, DP41, DP42 and DP5, using a molecular docking protocol. Dockings to virtual combinatorial peptide libraries were performed at pH 5.0 and pH 7.0. Results The X-ray structure of the peptide – HLA-DP2 protein complex was used as a starting template to model by homology the structure of the four DP proteins. The resulting models were used to produce virtual combinatorial peptide libraries constructed using the single amino acid substitution (SAAS) principle. Peptides were docked into the DP binding site using AutoDock at pH 5.0 and pH 7.0. The resulting scores were normalized and used to generate Docking Score-based Quantitative Matrices (DS-QMs). The predictive ability of these QMs was tested using an external test set of 484 known DP binders. They were also compared to existing servers for DP binding prediction. The models derived at pH 5.0 predict better than those derived at pH 7.0 and showed significantly improved predictions for three of the four DP proteins, when compared to the existing servers. They are able to recognize 50% of the known binders in the top 5% of predicted peptides. Conclusions The higher predictive ability of DS-QMs derived at pH 5.0 may be rationalised by the additional hydrogen bond formed between the backbone carbonyl oxygen belonging to the peptide

  1. Evaluation of fungal- and photo-degradation as potential treatments for the removal of sunscreens BP3 and BP1.

    PubMed

    Gago-Ferrero, Pablo; Badia-Fabregat, Marina; Olivares, Alba; Piña, Benjamin; Blánquez, Paqui; Vicent, Teresa; Caminal, Gloria; Díaz-Cruz, M Silvia; Barceló, Damià

    2012-06-15

    Photodecomposition might be regarded as one of the most important abiotic factors affecting the fate of UV absorbing compounds in the environment and photocatalysis has been suggested as an effective method to degrade organic pollutants. However, UV filters transformation appears to be a complex process, barely addressed to date. The white rot fungus Trametes versicolor is considered as a promising alternative to conventional aerobic bacterial degradation, as it is able to metabolise a wide range of xenobiotics. This study focused on both degradation processes of two widely used UV filters, benzophenone-3 (BP3) and benzophenone-1 (BP1). Fungal treatment resulted in the degradation of more than 99% for both sunscreens in less than 24 h, whereas photodegradation was very inefficient, especially for BP3, which remained unaltered upon 24 h of simulated sunlight irradiation. Analysis of metabolic compounds generated showed BP1 as a minor by-product of BP3 degradation by T. versicolor while the main intermediate metabolites were glycoconjugate derivatives. BP1 and BP3 showed a weak, but significant estrogenic activity (EC50 values of 0.058 mg/L and 12.5 mg/L, respectively) when tested by recombinant yeast assay (RYA), being BP1 200-folds more estrogenic than BP3. Estrogenic activity was eliminated during T. versicolor degradation of both compounds, showing that none of the resulting metabolites possessed significant estrogenic activity at the concentrations produced. These results demonstrate the suitability of this method to degrade both sunscreen agents and to eliminate estrogenic activity.

  2. The Tista Megafan, a ~50 kyr Record of Drainage Development, Erosion and Weathering in the Sikkim Himalayas (Eastern India)

    NASA Astrophysics Data System (ADS)

    Abrahami, R.; Huyghe, P.; Van Der Beek, P.; Lowick, S.; Garzanti, E.; Revillon, S.; Carcaillet, J.; Chakraborty, T.

    2015-12-01

    The Tista River, a major tributary of the Brahmaputra drainage system (Eastern Himalaya) has built a fluvial deposit which extents over 16500 km2. The Tista megafan stands out because of (1) its disproportionate size compared to that of the upstream Tista River catchment (8000 km2), and (2) it has been incised about 50m by the river at the topographic front of the mountain range. Neither the timing of deposition/incision of the megafan sediments, and their potential tectonic or climatic controls have yet been investigated. We use both IRSL and 10Be cosmogenic data to respectively constrain the date of deposition and abandonment of the different lobes of the megafan. We suggest that two distal lobes developed successively downstream from a common proximal lobe. Deposition took place since ~50 ka and incision began at 4.0 +0.6/-0.4 ka at an average rate of 10.5 +0.6/-1.8 mm yr-1. In addition, petrology, isotope geochemistry (ɛNd, 87Sr/86Sr) and chemical composition performed on modern river sands and late-Quaternary megafan sediments allows characterizing (1) provenance variations through time of megafan deposits and their implication for drainage development (2) the weathering history of Sikkim recorded by the megafan deposits. Results show that the Tista fan deposits are mainly sourced from the High Himalayan Crystalline domain and the Tethyan Sedimentary Series, (consistent with high erosion rates identified in north Sikkim at millennial timescale). Variations in provenance and weathering through time recorded by the Tista megafan deposits can be linked to climatic variations with strong monsoonal precipitations penetrating further northward into the southern Tibetan plateau. Tectonic processes seem to play a minor role. Otherwise, we propose as a first hypothesis that the Kosi River has recently (at ~4 ka) captured the upper part of the Tista catchment. That could explain the particular isotopic signature of the Tista megafan deposits, its recent incision, its

  3. Trailer siting issues: BP Texas City.

    PubMed

    Kaszniak, Mark; Holmstrom, Donald

    2008-11-15

    On 23 March, 2005, a series of explosions and fires occurred at the BP Texas City refinery during the startup of an isomerization (ISOM) process unit. Fifteen workers were killed and about 180 others were injured. All of the fatalities were contract workers; the deaths and most of the serious injuries occurred in and around temporary office trailers that had been sited near a blowdown drum and stack open to the atmosphere as part of ongoing turnaround activities in an adjacent unit. Due to problems that developed during the ISOM startup, flammable hydrocarbon liquid overfilled the blowdown drum and stack which resulted in a geyser-like release out the top into the atmosphere. The flammable hydrocarbons fell to the ground releasing vapors that were likely ignited from a nearby idling diesel pickup truck. A total of 44 trailers were damaged by the blast pressure wave that propagated through the refinery when the vapor cloud exploded. Thirteen trailers were totally destroyed and workers were injured in trailers as far as 479ft away from the release. The focus of this paper will be on trailer siting issues, including: need for work/office trailers within process units, adequacy of risk analysis methods in API RP 752, and minimum safe distance requirements

  4. Suzaku observations of two diffuse hard X-ray source regions, G22.0+0.0 and G23.5+0.1

    NASA Astrophysics Data System (ADS)

    Yamauchi, Shigeo; Sumita, Mayu; Bamba, Aya

    2016-06-01

    G22.0+0.0 and G23.5+0.1 are diffuse hard X-ray sources discovered in the ASCA Galactic Plane Survey. We present Suzaku results of spectral analysis for these sources. G22.0+0.0 is confirmed to be a largely extended emission. Its spectra were represented by a highly absorbed power-law model with a photon index of 1.7 ± 0.3 and a moderately absorbed thermal emission with a temperature of 0.34^{+0.11}_{-0.08}keV. The difference in the NH values between the two components suggests that the thermal component is unrelated to the power-law component and is a foreground emission located in the same line of sight. G23.5+0.1 is an extended source with a size of ˜3{^'.}5. Its spectra were fitted with an absorbed power-law model with a photon index of 2.4^{+0.5}_{-0.4}. The spatial and spectral properties show that both sources are candidates for old pulsar wind nebulae (PWNe). In addition to the extended sources, we analyzed spectra of three point sources found in the observed fields. Based on the spectral features, we discuss the origin of the sources.

  5. Magnetic and Transport Properties of RESn xSb 2 ( RE=La, Ce, Pr, Nd, Sm; x=0.5, 0.7)

    NASA Astrophysics Data System (ADS)

    Deakin, Laura; Ferguson, Michael J.; Sprague, Michael J.; Mar, Arthur; Sharma, R. D.; Jones, Colin H. W.

    2002-03-01

    The nonstoichiometric rare-earth tin antimonides RESnxSb2 (RE=La, Ce, Pr, Nd, Sm) were characterized by 119Sn Mössbauer spectroscopy and their transport and magnetic properties were measured. The presence of nearly zero-valent Sn is suggested by the similarity of the 119Sn Mössbauer parameters in LaSnxSb2 (0.1≤x≤0.7) to those of elemental β-Sn. All RESn0.7Sb2 compounds exhibit metallic behavior. CeSn0.7Sb2 and NdSn0.7Sb2 show drops in resistivity below 8 K; this is attributed to a transition to a magnetically ordered state. At 25 K, CeSn0.7Sb2 also displays a resistivity minimum characteristic of ordered Kondo lattices. Magnetic studies indicate that, below 4 K, CeSnxSb2 (x=0.5, 0.7) orders ferromagnetically, whereas NdSnxSb2 (x=0.5, 0.7) orders antiferromagnetically and undergoes a metamagnetic transition at HC=5.5 T and 2 K. Neither PrSnxSb2 nor SmSnxSb2 (x=0.5, 0.7) displays long-range magnetic ordering above 2 K.

  6. Oxygen isotopes of Pacific seawater, 0-40 kyr, based on d18O and Mg/Ca of benthic and planktic foraminifera: relation to deglacial sealevel rise.

    NASA Astrophysics Data System (ADS)

    Mix, A. C.; Klinkhammer, G. P.

    2007-12-01

    Combining high resolution (~200 year sample resolution) oxygen and carbon isotope measurements and Mg/Ca analyses in planktic (G. ruber and N. dutertrei) and benthic foraminifera (Uvigerina sp.; use of infaunal benthics minimizes likely CO3= effects) from the mid-depth eastern Pacific provides for detailed estimates of changing d18O of seawater over the past 40 kyr at ODP Site 1242. The key to this analysis is improved precision of the Mg/Ca analyses based on a new generation of high precision flow-through time-resolved analysis (FT-TRA) (e.g., average internal precision for Mg/Ca is now +/-0.005 benthic, and +/-0.015 planktic). This method is relatively insensitive to mild dissolution of heterogeneous shells, and thus requires no corrections for preservation. The change in seawater d18O (at 1364 m depth) between the Holocene and Last Glacial Maximum is 1.2 +/- 0.04 permil when averaged over the stages, consistent with pore-water diffusion estimates; however, millennial scale events (which the pore-water data cannot detect) bring the total range up to about 1.6 permil. Are such short-term events related to sealevel change, or do they reflect changing watermasses? Measurements of d13C data (C. wuellerstorfi), sensitive to modern subsurface watermass gradients, are not highly correlated to short- term changes in d18Oseawater suggesting a transient response to ice volume changes. Glacial weakening of AAIW (salty, high d18O, high d13C) relative to north Pacific watermasses (fresher, lower d18O, low d13C) suggest that the benthic d18Oseawater may underestimate total local changes related to ice volume (with a caveat regarding proper scaling of benthic Mg/Ca to temperature). Benthic d18Oseawater falls through the deglaciation in steps, starting at 18 cal ka, with maximum rates of change at 14-15 ka, and with secondary rapid steps at 16-17 ka and 10-11 kar. Planktic foraminifera yield smaller glacial-interglacial d18Oseawater values, with Holocene-to-LGM stage- average

  7. An early Pleistocene Mg/Ca-δ18O record from the Gulf of Mexico: Evaluating ice sheet size and pacing in the 40-kyr world

    NASA Astrophysics Data System (ADS)

    Shakun, J. D.; Raymo, M. E.; Lea, D. W.; Klinkhammer, G. P.

    2011-12-01

    Two decades ago, Joyce (1993) presented a planktonic δ18O record from ODP site 625 in the Gulf of Mexico and interpreted numerous light isotope excursions beginning at 2.5 Ma as reflecting Laurentide Ice Sheet meltwater pulses down the Mississippi River. This finding implied an extensive early Pleistocene (EP) ice sheet, seemingly at odds with the smaller global ice volume inferred from benthic δ18O at this time. The till record on land confirms that ice extended into the central U.S at least twice during the EP. We are developing a high-resolution paired Mg/Ca-δ18O record from site 625 to reconstruct sea surface temperatures and salinity over the EP and evaluate Joyce's meltwater interpretation. Initial results of our temperature-corrected δ18O record confirm his inference of large meltwater spikes at the onset of the Quaternary. Our approach could weigh in on several hypotheses concerning the size and pacing of Quaternary ice sheets. The Integrated Insolation hypothesis explains the puzzling lack of precession variability in marine δ18O during the 40-kyr world by arguing that ice sheets are sensitive to insolation integrated over the summer, which is largely controlled by obliquity. The Antiphase Hypothesis, on the other hand, suggests that EP precession variability was antiphased between northern and southern ice sheets, canceling out and leaving the in-phase obliquity component to dominate the marine δ18O record. This view implies that marine δ18O may underestimate Northern Hemisphere ice volume during the EP. The Regolith Hypothesis takes the small ice volume implied by marine δ18O at face value and, together with the large ice area suggested from Joyce's meltwater spikes and the mid-continent till record, argues that EP ice sheets had a flat-like-a-pancake geometry, which it attributes to fast ice flow over a deformable bed. Erosion of this bed in the mid-Pleistocene may then have led to larger, more sluggish ice sheets and the transition from 40 to

  8. New Archaeointensity Result from Middle-Eastern China and Its Constraints on the Variation of the Geomagnetic Field during the last 6 kyr

    NASA Astrophysics Data System (ADS)

    Cai, S.; Jin, G.; Deng, C.; Tauxe, L.; Qin, H.; Pan, Y.; Zhu, R.

    2015-12-01

    Archaeomagnetic study is an effective way to understand the variation of the geomagnetic field over periods of hundreds to thousands of years. We have carried out archaeointensity studies on archaeological artifacts, including pottery fragments, bricks and baked clay, collected from several sites covering the middle to eastern part of China spanning the past ~6 kyr. We designed detailed rock magnetic and archaeointensity experiments in this study. Rock magnetic results indicate that the main magnetic carriers of these samples are stable magnetite or titanomagnetite with mainly fine particles of SD and SP. About 40% of the specimens in the paleointensity experiment pass the strict selection criteria and are considered to record robust intensity values. The virtual axial dipole moments (VADMs) of our sites range from ~2.5×1022 to ~15.8×1022 Am2. We record three low intensity values with VADMs of less than 3×1022 Am2, two of them comparable to the one reported by Cai et al. (2015) at ~3000 BCE while the other one comparable to those reported by Cai et al. (2014) at ~2200 BCE, which supply further evidence for the existence of 'DIPs' (decreases in paleoinetnsity) in China during the period of ~3000-2000 BCE. A high intensity value of ~16×1022 Am2 is recorded by our new data at ~1300 BCE, which may represent a new spike at this time period. The low and high values recorded by our new data update the six-fold variation between ~2200 BCE and ~1300 BCE discussed in Cai et al. (2014) to eight-fold, which may indicate a stronger geodynamic process during this period. Our new data are generally in good agreement with the published data in China, Japan and Korea at similar time periods, except the extreme low and high values discussed above, which will improve the Eastern Asian model greatly. The new data together with the published data suggest severe fluctuation of the geomagnetic field in Eastern Asia during the last 6 kyr. Vast quantities of reliable data are needed to

  9. Changes in seasonality of organic matter supply to the sea floor in the Eastern Equatorial Pacific over the last 260 kyr based on benthic foraminiferal assemblages

    NASA Astrophysics Data System (ADS)

    Ovsepyan, Ekaterina; Ivanova, Elena; Vidal, Laurence

    2015-04-01

    At present, short- and long-term variations of sea-surface biological productivity in the Eastern Equatorial Pacific have been extensively studied in order to evaluate changes in efficiency of biological carbon dioxide pump in the past. Benthic foraminiferal assemblages are investigated from the IMAGES giant Core MD02-2529 (8°12.5' N, 84° 07.5'W, w.d. 1619 m) off Costa Rica recovered the last 262 kyr according to oxygen isotope stratigraphy confirmed by 15 AMS14C dates in the upper part of the core. A predominance of high productivity species (e.g. hispid Uvigerina, U. peregrina, M. barleeanus, B. mexicana, C. carinata, T. delicata, C. wuellerstorfi, P. bulloides, Chilostomella spp., Globobulimina spp.) in benthic foraminiferal assemblages indicates intensive organic matter supply to the sea floor throughout the interval studied. CABFAC factor analysis applied for the species percentages matrix reveals that changes in taxonomic composition are described by three factors. Factor 1 is loaded mainly to U. hispida and in a less degree to U. peregrina. According to the modern ecological notion (e.g. Loubere, Fariduddin, 1999), U. hispida is associated with high and fairly constant organic matter flux to the seabed. Hence, high values of factor 1 reflect high productivity and low seasonality conditions. Factor 2 is loaded positively to U. peregrina and negatively to U. hispida. U. peregrina prefers slightly degraded organic matter, whereas U. hispida is abundant within the regions where organic matter is fresh and dominated by diatoms. Thus, we suppose that maxima of factor 2 mirror high productivity conditions with non-regular flux of organic matter to the sea floor with several events of phytoplankton blooms over the year (moderate seasonality). We believe that fresh organic matter derived from the photic layer underwent bacterial decomposition between multiple flux pulses and thereby contributed to thrift U. peregrina assemblages. Factor 3 is loaded positively to M

  10. Expanding the BP1-BP2 15q11.2 Microdeletion Phenotype: Tracheoesophageal Fistula and Congenital Cataracts.

    PubMed

    Wong, D; Johnson, S M; Young, D; Iwamoto, L; Sood, S; Slavin, T P

    2013-01-01

    The proximal q arm of chromosome 15 contains breakpoint regions BP1-BP5 with the classic deletion of BP1-BP3 best known to be associated with Prader-Willi and Angelman syndromes. The region is approximately 500 kb and microdeletions within the BP1-BP2 region have been reported in patients with developmental delay, behavioral abnormalities, and motor apraxia as well as dysmorphic features including hypertelorism, cleft or narrow palate, ear abnormalities, and recurrent upper airway infections. We report two patients with unique, never-before-reported 15q11.2 BP1-2 microdeletion syndrome findings, one with proximal esophageal atresia and distal tracheoesophageal fistula (type C) and one with congenital cataracts. Cataracts have been described in Prader-Willi syndrome but we could not find any description of cataracts in Angelman syndrome. Esophageal atresia and tracheoesophageal fistula have not been reported to our knowledge in either syndrome. A chance exists that both cases are sporadic birth defects; however, the findings of the concomitant microdeletion cannot be overlooked as a possible cause. Based on our review of the literature and the presentation of our patients, we recommend that esophageal atresia and distal tracheoesophageal fistula as well as congenital cataracts be included in the phenotypic spectrum of 15q11.2 BP1-2 microdeletion syndrome.

  11. ED 03-2 HOME BLOOD PRESSURE MONITORING IS BETTER THAN OFFICE BP AND AMBULATORY BP: UPDATE.

    PubMed

    Kario, Kazuomi

    2016-09-01

    Out-of-office blood pressure (BP) measured by home BP monitoring (HBPM) or ambulatory BP monitoring (ABPM) was demonstrated to be superior to office BP for the prediction of cardiovascular events. The ABPM is superior to HBPM for detecting the all the BP-related risks throughout 24-hr, and the self-measured HBPM underestimates the risk of daytime stress hypertension and nocturnal hypertension. However, ABPM cannot always be provided in clinical practice, and home BP monitoring can be superior to ABPM as part of a home BP-guided antihypertension strategy in clinical practice. In clinical practice, we should use both ABPM and HBPM considering these device properties. We have developed the new ABPM device which is alternatively used as self-measure HBPM (Kario. Prog Cardiovasc Dis 2016, in press).The importance of on-treatment HBPM for the cardiovascular prognosis of hypertensive individuals was recently revealed in the largest real-world prospective study held to date, the Home blood pressure measurement with Olmesartan Naive patients to Establish Standard Target blood pressure (HONEST) study. That study of more than 21 000 hypertensive patients used HBPM, and the results demonstrated that when morning home systolic BP was well-controlled during the 2-year follow-up at < 125 mmHg, there was no increase in cardiovascular events even among the patients whose office systolic BP was ≥150 mmHg, compared with those with office systolic BP < 130 mmHg and morning home systolic BP < 125 mmHg. On the other hand, even when the office systolic BP of the HONEST study's hypertensive patients was well controlled at < 130 mmHg, the hazard ratio of cardiovascular events was 2.5 in the masked uncontrolled hypertension patients with morning systolic BP ≥145 mmHg compared with the well-controlled patients with morning systolic BP < 125 mmHg (Kario, et al. Hypertension 2014;64:989-996). The threshold of on-treatment morning BP for a significant increase in

  12. Evolution of the North Pacific Subtropical Gyre during the past 190 kyr through the interaction of the Kuroshio Current with the surface and intermediate waters

    NASA Astrophysics Data System (ADS)

    Ujiié, Yurika; Asahi, Hirofumi; Sagawa, Takuya; Bassinot, Franck

    2016-11-01

    The North Pacific Subtropical Gyre (NPSG) has two important functions, i.e., one in ocean heat transfer and another as a driving force for circulation of the surface and intermediate waters on the basin scale. In the present study, we describe records of the vertical thermal structures and distributions of water masses in the upper ocean of the subtropical northwest (NW) Pacific for the past 190 kyr, using two sediment cores collected from the Kuroshio Current area in the East China Sea and the NPSG area. During the two glacial periods, the Kuroshio Current was weakened owing to changes in ocean-atmosphere circulation and eustasy. The differences in the Mg/Ca-derived temperatures between surface and thermocline waters show the changes of depth and temperature (warming) of thermocline during glacial periods. Conversely, the planktonic foraminiferal assemblages demonstrate that the indicator of the intermediate water from the central area of the NPSG increased synchronously with thermocline warming during marine isotope stage (MIS) 6. These results suggest that warm intermediate water strongly affected the changes in the water-column structure of the subtropical NW Pacific during MIS 6. However, during MIS 2, cold water had precedence over intermediate water probably owing to the southward shift of the subtropical front associated with the reduced transport of the Kuroshio Current. Thus, the NPSG has evolved differently during the two glacial periods (MIS 2 and MIS 6) through interactions between the Kuroshio Current, surface water, and intermediate water.

  13. Millennial-scale variability of marine productivity and terrigenous matter supply in the western Bering Sea over the past 180 kyr

    NASA Astrophysics Data System (ADS)

    Riethdorf, J.-R.; Nürnberg, D.; Max, L.; Tiedemann, R.; Gorbarenko, S. A.; Malakhov, M. I.

    2012-12-01

    We used piston cores recovered in the western Bering Sea to reconstruct millennial-scale changes in marine productivity and terrigenous matter supply over the past ~180 kyr. Based on a geochemical multi-proxy approach our results indicate closely interacting processes controlling marine productivity and terrigenous matter supply comparable to the situation in the Okhotsk Sea. Overall, terrigenous inputs were high, whereas primary production was low. Minor increases in marine productivity occurred during warm intervals of stage 5 and interstadials, but pronounced maxima were recorded during interglacials and Termination I. Seasonal sea-ice is suggested to act as the dominant transport agent for terrigenous material. From our results we propose glacial, deglacial, and interglacial scenarios for environmental change in the Bering Sea. These changes seem to be primarily controlled by insolation and sea-level forcing which affect the strength of atmospheric pressure systems and sea-ice growth. The opening history of the Bering Strait and the Aleutian passes is considered to have had an additional impact. Sea-ice dynamics are thought to drive changes in surface productivity, terrigenous inputs, and upper-ocean stratification. High-resolution core logging data (color b*, XRF scans) strongly correspond to the Dansgaard-Oeschger climate variability registered in the NGRIP ice core and support an atmospheric coupling mechanism of Northern Hemisphere climates.

  14. Millennial-scale variability of marine productivity and terrigenous matter supply in the western Bering Sea over the past 180 kyr

    NASA Astrophysics Data System (ADS)

    Riethdorf, J.-R.; Nürnberg, D.; Max, L.; Tiedemann, R.; Gorbarenko, S. A.; Malakhov, M. I.

    2013-06-01

    We used piston cores recovered in the western Bering Sea to reconstruct millennial-scale changes in marine productivity and terrigenous matter supply over the past ~180 kyr. Based on a geochemical multi-proxy approach, our results indicate closely interacting processes controlling marine productivity and terrigenous matter supply comparable to the situation in the Okhotsk Sea. Overall, terrigenous inputs were high, whereas export production was low. Minor increases in marine productivity occurred during intervals of Marine Isotope Stage 5 and interstadials, but pronounced maxima were recorded during interglacials and Termination I. The terrigenous material is suggested to be derived from continental sources on the eastern Bering Sea shelf and to be subsequently transported via sea ice, which is likely to drive changes in surface productivity, terrigenous inputs, and upper-ocean stratification. From our results we propose glacial, deglacial, and interglacial scenarios for environmental change in the Bering Sea. These changes seem to be primarily controlled by insolation and sea-level forcing which affect the strength of atmospheric pressure systems and sea-ice growth. The opening history of the Bering Strait is considered to have had an additional impact. High-resolution core logging data (color b*, XRF scans) strongly correspond to the Dansgaard-Oeschger climate variability registered in the NGRIP ice core and support an atmospheric coupling mechanism of Northern Hemisphere climates.

  15. A 100 Myr history of the carbon cycle based on the 400 kyr cycle in marine δ13C benthic records

    NASA Astrophysics Data System (ADS)

    Paillard, Didier; Donnadieu, Yannick

    2014-12-01

    Documenting the past coevolution of Earth temperatures and of the carbon cycle is of paramount importance for our understanding of climate dynamics. Atmospheric CO2 is well constrained over the last million years through direct measurements in air bubbles from Antarctic ice cores. For older times, many different and sometimes conflicting proxies have been suggested. Here we provide a new methodology to constrain the carbon cycle in the past, based on marine benthic δ13C records. Marine δ13C data are recording a persistent 400 kyr cycle, with an amplitude primarily linked to the total amount of carbon in the ocean, or dissolved inorganic carbon (DIC). By extracting this amplitude from published records, we obtain a new strong constraint on the 100 Myr history of Earth's carbon cycle. The obtained Cenozoic evolution of DIC is in surprisingly in a good agreement with existing reconstructions of pCO2, suggesting that pCO2 is mostly driven by DIC changes over this period. In contrast, we find no strong decreasing trend in DIC between the Cretaceous and the Cenozoic, suggesting that Cretaceous atmospheric pCO2 levels were limited, and high temperatures at this time should be explained by other mechanisms. Alternatively, high Cretaceous atmospheric pCO2 could occur as a consequence of changes in oceanic chemistry but not carbon content.

  16. Linkages between rapid climate variability and deep-sea benthic foraminifera in the deep Subantarctic South Atlantic during the last 95 kyr

    NASA Astrophysics Data System (ADS)

    Diz, Paula; Barker, Stephen

    2015-06-01

    We present a high-resolution record of benthic foraminifera fauna from a sediment core retrieved from the South Cape Basin (Subantarctic South Atlantic) spanning the last glacial cycle (95 kyr). Information provided by benthic foraminiferal assemblages together with paleoclimate proxies from the same core allow us to interpret changes in the style of primary production (episodic versus sustained) in relation to abrupt climate oscillations. Our results indicate that fluctuations in the abundance of the phytodetritus-related species, Epistominella exigua, are concomitant with millennial-scale high-latitude climate perturbations. Episodic phytoplankton blooms increased during a negative mode of the bipolar seesaw, irrespective of the magnitude of the perturbation (i.e., Heinrich stadial versus non-Heinrich stadial events). We provide a hypothesis linking the frequency and intensity of these events to atmospheric perturbations, interhemispheric climate variability, and millennial-scale changes in atmospheric CO2. A notable exception to the overall pattern is the generally high abundance of E. exigua across the globally synchronous onset of glacial marine oxygen isotope stage (MIS) 4, a period generally characterized by increased dustiness and low-quality organic carbon as inferred by the percentage of the nonphytodetritus species. This highlights the special characteristics governing the onset of MIS 4 in the Subantarctic.

  17. Lack of CaBP1/Caldendrin or CaBP2 Leads to Altered Ganglion Cell Responses

    PubMed Central

    Sinha, Raunak; Lee, Amy

    2016-01-01

    Calcium-binding proteins (CaBPs) form a subfamily of calmodulin-like proteins that were cloned from the retina. CaBP4 and CaBP5 have been shown to be important for normal visual function. Although CaBP1/caldendrin and CaBP2 have been shown to modulate various targets in vitro, it is not known whether they contribute to the transmission of light responses through the retina. Therefore, we generated mice that lack CaBP2 or CaBP1/caldendrin (Cabp2–/– and Cabp1–/–) to test whether these CaBPs are essential for normal retinal function. By immunohistochemistry, the overall morphology of Cabp1–/– and Cabp2–/– retinas and the number of synaptic ribbons appear normal; transmission electron microscopy shows normal tethered ribbon synapses and synaptic vesicles as in wild-type retinas. However, whole-cell patch clamp recordings showed that light responses of retinal ganglion cells of Cabp2–/– and Cabp1–/– mice differ in amplitude and kinetics from those of wild-type mice. We conclude that CaBP1/caldendrin and CaBP2 are not required for normal gross retinal and synapse morphology but are necessary for the proper transmission of light responses through the retina; like other CaBPs, CaBP1/caldendrin and CaBP2 likely act by modulating presynaptic Ca2+-dependent signaling mechanisms. PMID:27822497

  18. High Efficacy of Finafloxacin on Helicobacter pylori Isolates at pH 5.0 Compared with That of Other Fluoroquinolones

    PubMed Central

    Lee, Jung Won; Nam, Ryoung Hee; Kim, Jung Mogg; Park, Jong Youn; Lee, Sun Min; Kim, Joo Sung; Lee, Dong Ho; Jung, Hyun Chae

    2015-01-01

    Finafloxacin is a novel fluoroquinolone with improved antimicrobial efficacy, especially in an acidic environment. The efficacy of finafloxacin for the inhibition of Helicobacter pylori infection was compared with the efficacies of levofloxacin and moxifloxacin at neutral and acidic pH. The impacts of gyrA point mutation on the efficacy of those three fluoroquinolones were also investigated. A total of 128 clinical H. pylori strains were utilized. MICs of levofloxacin, moxifloxacin, and finafloxacin were determined at pH 5.0 and pH 7.0 by the agar dilution method. The impact of gyrA point mutations that are responsible for fluoroquinolone resistance was analyzed; the results showed 50 strains with an Asn-87 point mutation, 48 strains with an Asp-91 point mutation, and the remaining 30 strains with no gyrA mutations. The use of finafloxacin led to MIC values at pH 5.0 that were lower than the values seen at pH 7.0 for 112 strains (112/128, 87.5%), and this proportion was higher than that seen with moxifloxacin (21/128, 16.4%, P < 0.001). Finafloxacin also demonstrated a rate of susceptibility (MIC, <1 μg/ml) (37.5%, 48/128) at pH 5.0 that was higher than that seen with moxifloxacin (2.3%, 3/128) (P < 0.001). The trends were similar regardless of which of the Asn-87, Asp-91, and A2143 point mutations were present. In conclusion, the superior antimicrobial efficacy of finafloxacin against H. pylori in an acidic environment suggests the possible use of finafloxacin for treatment of H. pylori infection, as has been proposed by its developer, Merlion Pharma. PMID:26416863

  19. SD 1313-0019: Another Second-generation Star with [Fe/H] = -5.0, Observed with the Magellan Telescope

    NASA Astrophysics Data System (ADS)

    Frebel, Anna; Chiti, Anirudh; Ji, Alexander P.; Jacobson, Heather R.; Placco, Vinicius M.

    2015-09-01

    We present a Magellan/MIKE high-resolution (R ˜ 35,000) spectrum of the ancient star SD 1313-0019, which has an iron abundance of [Fe/H]=-5.0, paired with a carbon enhancement of [C/Fe]˜ 3.0. The star was initially identified by Allende Prieto et al. in the BOSS survey. Its medium-resolution spectrum suggested a higher metallicity of [Fe/H]=-4.3 due to the Ca II K line blending with a CH feature, which is a common issue related to the search for the most iron-poor stars. This star joins several other similar stars with [Fe/H]≲ -5.0 that all display a combination of low-iron and high-carbon abundances. Other elemental abundances of SD 1313-0019 follow that of more metal-rich halo stars. Fitting the abundance pattern with yields of Population III supernovae suggests that SD 1313-0019 had only one massive progenitor star with 20-30 M⊙ that must have undergone a mixing and fallback episode. Overall, there are now five stars known with [Fe/H]≲ -5.0 (1D local thermodynamic equilibrium abundances). This ever-increasing population of carbon-rich, iron-deficient stars can potentially constrain nucleosynthesis in Population III stars and their supernova explosions, the formation mechanisms of the first low-mass stars, and the nature of the first galaxies. This paper includes data gathered with the 6.5 m Magellan Telescopes located at Las Campanas Observatory, Chile.

  20. Possible enhancement of BP180 autoantibody production by herpes zoster.

    PubMed

    Kamiya, Koji; Aoyama, Yumi; Suzuki, Takahiro; Niwa, Haruo; Horio, Ai; Nishio, Eiichi; Tokura, Yoshiki

    2016-02-01

    Bullous pemphigoid (BP) is an autoimmune blistering disease caused by autoantibodies against type XVII collagen/BP180 (BP180). Although the mechanisms of autoantibody production remain to be elucidated, herpes virus infections have been identified as a possible triggering factor for pemphigus. We report a case of herpes zoster (HZ) having anti-BP180 serum antibodies. The patient developed sudden-onset, tense blisters and edematous erythema on the right anterior chest, shoulder and upper back. Histopathology showed remarkable degeneration of keratinocytes, acantholysis and blister formation with ballooning cells, indicating herpes virus infection. A polymerase chain reaction analysis of varicella zoster virus (VZV) was positive in crusts and effusions from the skin lesions, confirming the definitive diagnosis of HZ. Notably, we found that the patient had anti-BP180 serum antibodies in association with the occurrence of HZ. After successful treatment with valacyclovir hydrochloride for 7 days, the serum levels of anti-BP180 antibodies decreased in accordance with the improvement of skin lesions. These findings suggest that the production of anti-BP180 antibodies could be triggered by the reactivation of VZV.

  1. Using the Minimally Invasive Impella 5.0 via the Right Subclavian Artery Cutdown for Acute on Chronic Decompensated Heart Failure as a Bridge to Decision

    PubMed Central

    Bansal, Aditya; Bhama, Jay K.; Patel, Rajan; Desai, Sapna; Mandras, Stacy A.; Patel, Hamang; Collins, Tyrone; Reilly, John P.; Ventura, Hector O.; Parrino, P. Eugene

    2016-01-01

    Background: Outcomes of traditional mechanical support paradigms (extracorporeal membrane oxygenation, intraaortic balloon pump [IABP], and permanent left ventricular assist device [LVAD]) in acute decompensated heart failure have generally been suboptimal. Novel approaches, such as minimally invasive LVAD therapy (Impella 5.0 device), promise less invasive but equivalent hemodynamic support. However, it is yet unknown whether the outcomes with such devices support widespread acceptance of this new technology. We recently started utilizing the right subclavian artery (RSA) for Impella 5.0 implantation and report our early experience and outcomes with this novel approach. Methods: A single-center retrospective review was performed of 24 patients with acute on chronic decompensated heart failure who received the Impella 5.0 via the RSA from June 2011 to May 2014. The device was implanted via a cutdown through an 8-mm vascular graft sewn to the RSA. The device was positioned with fluoroscopy and transesophageal echocardiography. Results: The mean age of the patients was 51.29 years, and 75% were male. At implantation, all patients were mechanically ventilated on at least 2 inotropes with persistent cardiogenic shock, and 17 (70.8%) were on IABP support. Postimplantation, 21 (87.5%) tolerated extubation, and all 17 of the patients with IABPs tolerated discontinuation of IABP support. The reduction in the Model for End-Stage Liver Disease score preimplantation vs postimplantation was statistically significant (21.17 vs 14.88, P=0.0014), suggesting improvement in end organ function. A significant decrease was also seen in creatinine levels before and after implantation (2.17 mg/dL vs 1.50 mg/dL, P=0.0043). The endpoint of support included recovery in 6 patients (25.0%), permanent LVAD in 9 (37.5%), and heart transplantation in 2 (8.3%). Death occurred in 7 patients (29.2%) as a result of multisystem organ failure, infection, or patient withdrawal of care. Conclusion

  2. Assessment of SOLPS5.0 divertor solutions with drifts and currents against L-mode experiments in ASDEX Upgrade and JET

    NASA Astrophysics Data System (ADS)

    Aho-Mantila, L.; Potzel, S.; Coster, D. P.; Wischmeier, M.; Brix, M.; Fischer, R.; Marsen, S.; Meigs, A.; Müller, H. W.; Scarabosio, A.; Stamp, M. F.; Brezinsek, S.; the ASDEX Upgrade Team; JET Contributors, the

    2017-03-01

    The divertor solutions obtained with the plasma edge modelling tool SOLPS5.0 are discussed. The code results are benchmarked against carefully analysed L-mode discharges at various density levels with and without impurity seeding in the full-metal tokamaks ASDEX Upgrade and JET. The role of the cross-field drifts and currents in the solutions is analysed in detail, and the improvements achieved by fully activating the drift and current terms in view of matching the experimental signals are addressed. The persisting discrepancies are also discussed.

  3. Surface nitrate utilization in the Bering sea since 180 kA BP: Insight from sedimentary nitrogen isotopes

    NASA Astrophysics Data System (ADS)

    Riethdorf, Jan-Rainer; Thibodeau, Benoit; Ikehara, Minoru; Nürnberg, Dirk; Max, Lars; Tiedemann, Ralf; Yokoyama, Yusuke

    2016-03-01

    We present high-resolution records of sedimentary nitrogen (δ15Nbulk) and carbon isotope ratios (δ13Cbulk) from piston core SO201-2-85KL located in the western Bering Sea. The records reflect changes in surface nitrate utilization and terrestrial organic matter contribution in submillennial resolution that span the last 180 kyr. The δ15Nbulk record is characterized by a minimum during the penultimate interglacial indicating low nitrate utilization (~62-80%) despite the relatively high export production inferred from opal concentrations along with a significant reduction in the terrestrial organic matter fraction (mterr). This suggests that the consumption of the nitrate pool at our site was incomplete and even more reduced than today (~84%). δ15Nbulk increases from Marine Isotope Stage (MIS) 5.4 and culminates during the Last Glacial Maximum, which indicates that nitrate utilization in the Bering Sea was raised during cold intervals (MIS 5.4, 5.2, 4) and almost complete during MIS 3 and 2 (~93-100%). This is in agreement with previous hypotheses suggesting that stronger glacial stratification reduced the nutrient supply from the subeuphotic zone, thereby increasing the iron-to-nutrient ratio and therefore the nitrate utilization in the mixed surface layer. Large variations in δ15Nbulk were also recorded from 180 to 130 ka BP (MIS 6), indicating a potential link to insolation and sea-level forcing and its related feedbacks. Millennial-scale oscillations were observed in δ15Nbulk and δ13Cbulk that might be related to Greenland interstadials.

  4. Pelagic-benthic coupling within an upwelling system of the subtropical northeast Atlantic over the last 35 ka BP

    NASA Astrophysics Data System (ADS)

    McKay, C. L.; Filipsson, H. L.; Romero, O. E.; Stuut, J.-B. W.; Donner, B.

    2014-12-01

    We present a high resolution, multiproxy study of the relationship between pelagic and benthic environments of a coastal upwelling system in the subtropical NE Atlantic Ocean. Marine sediments corresponding to late MIS3 to the Holocene in the radiocarbon dated core GeoB7926, retrieved off Mauritania (21°N) were analysed to reconstruct productivity in surface waters and its linkage to deep waters during the last 35 ka BP. High latitude cold events and changes in atmospheric and oceanographic dynamics influenced upwelling intensity over this time period. Subsequently, this caused changes in primary productivity off this low-latitude coastal upwelling locality. The benthic foraminiferal fauna displays four main community shifts corresponding to fundamental climatic events, first of all during late MIS3 (35-28 ka BP), secondly from 28 to 19 ka BP (including Heinrich event 2 and the LGM), thirdly within Heinrich event 1, the Bølling Allerød and the Younger Dryas (18-11.5 ka BP) and finally during the Holocene (11.5-0 ka BP). In particular, strong pelagic-benthic coupling is apparent in MIS 3, as demonstrated by increased primary productivity, indicated by moderate DAR and the dominance of benthic foraminiferal species which prefer fresh phytodetritus. A decline in upwelling intensity and nutrient availability follows, which resulted in a proportionately larger amount of older, degraded matter, provoking a shift in the benthic foraminifera fauna composition. This rapid response of the benthic environment continues with a progressive increase in upwelling intensity due to sea level and oceanographic changes and according high surface production during the LGM. During Heinrich event 1 and the Younger Dryas, extreme levels of primary production actually hindered benthic environment through the development of low oxygen conditions. After this period, a final change in benthic foraminiferal community composition occurs which indicates a return to more oxygenated conditions

  5. Size effects on the structural, electronic, and optical properties of (5,0) finite-length carbon nanotube: An ab-initio electronic structure study

    NASA Astrophysics Data System (ADS)

    Tarighi Ahmadpour, Mahdi; Hashemifar, S. Javad; Rostamnejadi, Ali

    2016-07-01

    We use density functional computations to study the zero temperature structural, electronic, magnetic, and optical properties of (5,0) finite carbon nanotubes (FCNT), with length in the range of 4-44 Å. It is found that the structural and electronic properties of (5,0) FCNTs, in the ground state, converge at a length of about 30 Å, while the excited state properties exhibit long-range edge effects. We discuss that curvature effects enhance energy gap of FCNTs, in contrast to the known trend in the periodic limit. It is seen that compensation of curvature effects in two special small sizes may give rise to spontaneous magnetization. The obtained cohesive energies provide some insights into the effects of environment on the growth of FCNTs. The second-order difference of the total energies reveals an important magic size of about 15 Å. The optical and dynamical magnetic responses of the FCNTs to polarized electromagnetic pulses are studied by time dependent density functional theory. The results show that the static and dynamic magnetic properties mainly come from the edge carbon atoms. The optical absorption properties are described in terms of local field effects and characterized by Casida linear response method.

  6. How many clinic BP readings are needed to predict cardiovascular events as accurately as ambulatory BP monitoring?

    PubMed

    Eguchi, K; Hoshide, S; Shimada, K; Kario, K

    2014-12-01

    We tested the hypothesis that multiple clinic blood pressure (BP) readings over an extended baseline period would be as predictive as ambulatory BP (ABP) for cardiovascular disease (CVD). Clinic and ABP monitoring were performed in 457 hypertensive patients at baseline. Clinic BP was measured monthly and the means of the first 3, 5 and 10 clinic BP readings were taken as the multiple clinic BP readings. The subjects were followed up, and stroke, HARD CVD, and ALL CVD events were determined as outcomes. In multivariate Cox regression analyses, ambulatory systolic BP (SBP) best predicted three outcomes independently of baseline and multiple clinic SBP readings. The mean of 10 clinic SBP readings predicted stroke (hazards ratio (HR)=1.39, 95% confidence interval (CI)=1.02-1.90, P=0.04) and ALL CVD (HR=1.41, 95% CI=1.13-1.74, P=0.002) independently of baseline clinic SBP. Clinic SBPs by three and five readings were not associated with any CVD events, except that clinic SBP by three readings was associated with ALL CVD (P=0.015). Besides ABP values, the mean of the first 10 clinic SBP values was a significant predictor of stroke and ALL CVD events. It is important to take more than several clinic BP readings early after the baseline period for the risk stratification of future CVD events.

  7. Evaluation of the Specificity of BP3385 for Bordetella pertussis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    BP3385 has been proposed as a diagnostic PCR target for discriminating between Bordetella pertussis and other Bordetella species that also infect humans. Our results demonstrate this gene is also present in some strains of Bordetella hinzii and Bordetella bronchiseptica....

  8. The potential role of CacyBP/SIP in tumorigenesis.

    PubMed

    Ning, Xiaoxuan; Chen, Yang; Wang, Xiaosu; Li, Qiaoneng; Sun, Shiren

    2016-08-01

    Calcyclin-binding protein/Siah-1-interacting protein (CacyBP/SIP) was initially described as a binding partner of S100A6 in the Ehrlich ascites tumor cells and later as a Siah-1-interacting protein. This 30 kDa protein includes three domains and is involved in cell proliferation, differentiation, cytoskeletal rearrangement, and transcriptional regulation via binding to various proteins. Studies have also shown that the CacyBP/SIP is a critical protein in tumorigenesis. But, its promotion or suppression of cancer progression may depend on the cell type. In this review, the biological characteristics and target proteins of CacyBP/SIP have been described. Moreover, the exact role of CacyBP/SIP in various cancers is discussed.

  9. RMB Exchange Rate Forecast Approach Based on BP Neural Network

    NASA Astrophysics Data System (ADS)

    Ye, Sun

    RMB exchange rate system has reformed since July, 2005. This article chose RMB exchange rate data during a period from July, 2005 to September 2010 to establish BP neural network model to forecast RMB exchange rate in the future by using MATLAB software. The result showed that BP neural network is effective to forecast RMB exchange rate and also indicated that RMB exchange rate will continue to appreciate in the future.

  10. HEC-RAS 5.0 Vs. TELEMAC-2D: a model comparison for flood-hazard and flood-risk estimation

    NASA Astrophysics Data System (ADS)

    Ezzahra Maatar, Fatma; Domeneghetti, Alessio; Brath, Armando

    2015-04-01

    River flooding is considered among the most frequent catastrophic events causing dramatic consequences in terms of loss of human life and economic damages. Therefore, the flood-hazard and flood-risk management appear nowadays the fundamental activities that public bodies and authorities in charge have to implement in order to reduce human and socio-economic losses. In this context, our study specifically refers to a flood event occurred on January 19, 2014, along the Secchia River (a tributary of the Po River; North Italy), with the aim of evaluating the suitability of different numerical tools for the reproduction of the flood dynamics. During this specific event a failure on the main embankment caused the overflowing of an overall volume of about 40•106 m3 within 48 hours inundating nearly 200 km² of the floodplain area. Thus, our study aims at reproducing the inundation dynamics using two different fully bi-dimensional (2D) hydrodynamic models, both based on Saint-Venant equations: Telemac-2D and HEC-RAS 5.0 (Beta version). The former (Telemac-2D) is a widely employed and well known 2D model adopting a finite-element scheme based on triangular elements, while the latter, HEC-RAS 5.0, is the first, recently released, version of a coupled 1D-2D model that enables one to simulate river and floodplains interactions through a finite-volume scheme. Taking advantage of the historical observations, we investigate the suitability of the new 1D-2D model in reproducing the flood patterns testing its performance in case of different mesh resolutions (i.e. cell dimension ranging from 50 m to 200 m) and Digital Elevation Model accuracy (i.e. DEM resolution varying from 1 m to 50 m). Models' performances are thus compared with real observations in terms of flood patterns (i.e. overall flood extent and flood dynamics) and flood-hazard indexes (such as water depth, flow velocity, impulse, etc.). Finally, we compare the accuracy of both models on the reconstruction of recorded

  11. Black Phosphorus (BP) Nanodots for Potential Biomedical Applications.

    PubMed

    Lee, Hyun Uk; Park, So Young; Lee, Soon Chang; Choi, Saehae; Seo, Soonjoo; Kim, Hyeran; Won, Jonghan; Choi, Kyuseok; Kang, Kyoung Suk; Park, Hyun Gyu; Kim, Hee-Sik; An, Ha Rim; Jeong, Kwang-Hun; Lee, Young-Chul; Lee, Jouhahn

    2016-01-13

    Recently, the appeal of 2D black phosphorus (BP) has been rising due to its unique optical and electronic properties with a tunable band gap (≈0.3-1.5 eV). While numerous research efforts have recently been devoted to nano- and optoelectronic applications of BP, no attention has been paid to promising medical applications. In this article, the preparation of BP-nanodots of a few nm to <20 nm with an average diameter of ≈10 nm and height of ≈8.7 nm is reported by a modified ultrasonication-assisted solution method. Stable formation of nontoxic phosphates and phosphonates from BP crystals with exposure in water or air is observed. As for the BP-nanodot crystals' stability (ionization and persistence of fluorescent intensity) in aqueous solution, after 10 d, ≈80% at 1.5 mg mL(-1) are degraded (i.e., ionized) in phosphate buffered saline. They showed no or little cytotoxic cell-viability effects in vitro involving blue- and green-fluorescence cell imaging. Thus, BP-nanodots can be considered a promising agent for drug delivery or cellular tracking systems.

  12. Sediment transport process and East Asian monsoon evolution during the last 410 kyr in the northern South China Sea: a multi-proxy approach

    NASA Astrophysics Data System (ADS)

    Chen, Quan; Liu, Zhifei; Kissel, Catherine

    2015-04-01

    Terrigenous detrital materials buried at sea is a book documenting their whole life, including the continental environment where they originated from and the transport process they experienced. In order to reconstruct the East Asian monsoon evolution in late Quaternary, we need to read this book correctly. The key problem is to well understand the proxies and pick the right ones, because most of them are affected by several factors. In this study, clay and magnetic mineralogical measurements and geochemical XRF analyses were conducted on Core MD12-3432 taken from the northern South China Sea at 2125 m water depth during the CIRCEA cruise organized within Franco-Chinese LIA-MONOCL framework on board the R.V. Marion Dufresne. The age model is derived from both carbonate and magnetic stratigraphy. The clearly identified Laschamp and Iceland Basin geomagnetic excursions are used as tie points. Coupled earth magnetic field paleointensity and carbonate content record calibrated from XRF core scanned calcium intensity, we established a robust age model, indicating that Core MD12-3432 covers the last 410 kyr with an average sedimentation rate of 12.4 cm/kyr. The calibrated XRF-scan data provide high-resolution Ti/Ca, Al/Si and K/Al ratios. Ti/Ca and Al/Si ratios vary in phase, indicating strong clastic flux and short transport distances during glacials. Variations in K/Al ratio show an independent pattern, suggesting that temperature-driven chemical weathering is not the main control factor. Special attention needs therefore to be paid to the transport process. For that purpose, anisotropy of magnetic susceptibility was measured on discrete samples at 50 cm intervals. Orientations of the principal anisotropy axes could be reconstructed, using the NRM declination to orient the core in the horizontal plane. The maximum axis is relatively well oriented in the stratigraphic plane of the sedimentary magnetic fabric. A 90° shift is observed at the MIS 5-6 boundary, suggesting a

  13. 4,10-Dinitro-2,6,8,12-tetraoxa-4,10-diazatetracyclo[5.5.0.05,903,11]dodecane Synthesis

    NASA Astrophysics Data System (ADS)

    Maksimowski, Paweł; Gołofit, Tomasz

    2013-07-01

    4,10-Dinitro-2,6,8,12-tetraoxa-4,10-diazatetracyclo[5.5.0.05,903,11]dodecane (TEX) was obtained by nitrolysis of 1,4-diformyl-2,3,5,6-tetrahydroxypiperazine reaction using a mixture of fuming nitric acid and concentrated sulfuric acid. The optimal process temperature was 54-56°C. The yield of the synthesis depends inter alia on the rate the reactants are introduced into the reaction medium and on the time of conditioning of the reaction mixture. A maximal yield of ca. 40% was achieved at the reactant addition time of 2 h and conditioning time of 2 h. None of the other nitrating mixtures examined proved superior to the conventional nitrating mixture. The product was examined by high-performance liquid chromatography (HPLC), nuclear magnetic resonance (NMR), Fourier transform infrared (FTIR), and differential scanning calorimetry (DSC) techniques and the results are reported.

  14. Use of a Vascular Sheath in the Axillary Artery as an Alternative Access Approach for Placing an Impella 5.0 Device.

    PubMed

    Shah, Ankur S; Lee, Richard; Hui, Dawn S; Lim, Michael J; Neumayr, Robert H; Stolker, Joshua M

    2015-08-01

    Many patients who are in cardiogenic shock need mechanical support for clinical stabilization after acute insults such as myocardial infarction. However, the placement of advanced devices can be hindered by anatomic constraints or the physiologic sequelae of shock, as we describe in this report. A 67-year-old woman with prior coronary artery bypass grafting and extensive chest-wall scarring from previous defibrillator implantations presented with myocardial infarction and refractory cardiogenic shock. The patient's vascular anatomy and prior surgery precluded conventional percutaneous implantation of an Impella 5.0 ventricular support device. We delivered the Impella device through the patient's tortuous, vasoconstricted axillary artery with use of a vascular sheath and other percutaneous techniques. The success of this approach suggests that combining the expertise of cardiologists and cardiovascular surgeons can improve the outcomes of patients with complex anatomic issues.

  15. The 2.5-5.0 micron spectra of Io - Evidence for H2S and H2O frozen in SO2

    NASA Technical Reports Server (NTRS)

    Salama, F.; Allamandola, L. J.; Witteborn, F. C.; Cruikshank, D. P.; Sandford, S. A.

    1990-01-01

    The present analysis of IR spectra of Io in the 2.5-5.0 micron region with laboratory data on plausible surface ices gives attention to four unidentified features exhibiting spatial and temporal band strength variations; these fall close to the fundamental stretching modes in H2S and H2O, respectively. It is suggested that the 3.85- and 3.91-micron bands in the Io spectra can be accounted for by the absorption of the S-H stretching vibration in H2S clusters and isolated molecules in an SO2-dominated ice. The observations resemble the transmission spectra of SO2 ices that contain about 3 percent H2S and 0.1 percent H2O.

  16. Spectral radiative transfer for the 4.0- to 5.0-micron bands of CO and CO2 with mild vibrational relaxation and Doppler shift

    NASA Astrophysics Data System (ADS)

    Limbaugh, C. C.; Hiers, R. S., III; Phillips, W. J.

    1990-06-01

    This paper presents representative results for line-by-line spectral calculations of the 4.3-micron band of CO2 and the 5.0-micron band of CO in a nozzle-constrained, vibrationally relaxing combustion flow. The effects of property gradients are included, with special emphasis on the effects of the frequency shift of the radiation and absorption due to the component of velocity along the line of sight. Broadband spectra resulting from the convolution of the line-by-line results with a broadband filter are examined. It is shown that the effect of the Doppler shift is to broaden the individual spectral features with an attendant increase in the emitted radiation. Spectral detail is lost because of the broadening, and the greatest effect on the magnitude of the emission is for those lines which are optically thick.

  17. Fracture Test Results for 0.5, 0.7 and 0.9 Inch Thick 2324-T39 Aluminum Alloy Material

    NASA Technical Reports Server (NTRS)

    Johnston, William M.; Newman, James C., Jr. (Technical Monitor)

    2001-01-01

    A summary of experimental data is presented for a series of fracture tests and tensile tests that were conducted on a 2324-T39 aluminum alloy material. Static tensile tests were performed to determine the stress-strain response for the material. For the fracture tests three thicknesses (B = 0.5, 0.7, and 0.9-inches) and two specimen types (middle crack tension and compact tension specimens) were used. The middle crack tension specimens were 12-inches wide, and the compact tension specimens were 2, 4, and 6-inches wide. The fracture tests were conducted in the L-T orientation (crack perpendicular to the rolling direction and load parallel to the rolling direction).

  18. Short-term fluctuations in vegetation and phytoplankton during the Middle Eocene greenhouse climate: a 640-kyr record from the Messel oil shale (Germany)

    NASA Astrophysics Data System (ADS)

    Lenz, Olaf K.; Wilde, Volker; Riegel, Walter

    2011-11-01

    The Palaeogene was the most recent greenhouse period on Earth. Especially for the Late Palaeocene and Early Eocene, several superimposed short-term hyperthermal events have been described, including extremes such as the Palaeocene-Eocene Thermal Maximum. Major faunal and floral turnovers in the marine and terrestrial realms were recorded in association with these events. High-resolution palynological analysis of the early Middle Eocene maar lake sediments at Messel, near Darmstadt, Germany, provides an insight into the dynamics of a climax vegetation during the Middle Eocene greenhouse climate in a time span without significant climatic excursions. Numerical techniques like detrended correspondence analysis and wavelet analysis have been applied to recognize cyclic fluctuations and long-term trends in the vegetation through a time interval of approximately 640 kyr. Based on the numerical zoning of the pollen diagram, three phases in the development of the vegetation may be distinguished. Throughout these phases, the climax vegetation did not change substantially in qualitative composition, but a trend towards noticeably less humid conditions probably in combination with a drop of the water level in the lake may be recognized. A shift in algal population from the freshwater dinoflagellate cyst Messelodinium thielepfeifferae to a dominance of Botryococcus in the uppermost part of the core is interpreted as a response to changes in acidity and nutrient availability within the lake. Time series analyses of pollen assemblages show that variations in the Milankovitch range of eccentricity, obliquity and precession can be distinguished. In addition, fluctuations in the sub-Milankovitch range are indicated. This demonstrates that floral changes during steady depositional conditions in the Middle Eocene of Messel were controlled by orbital forcing.

  19. Rapid directional changes associated with a 6.5 kyr-long Blake geomagnetic excursion at the Blake-Bahama Outer Ridge

    NASA Astrophysics Data System (ADS)

    Bourne, Mark; Mac Niocaill, Conall; Thomas, Alex L.; Knudsen, Mads Faurschou; Henderson, Gideon M.

    2012-06-01

    Geomagnetic excursions are recognized as intrinsic features of the Earth's magnetic field. High-resolution records of field behaviour, captured in marine sedimentary cores, present an opportunity to determine the temporal and geometric character of the field during geomagnetic excursions and provide constraints on the mechanisms producing field variability. We present here the highest resolution record yet published of the Blake geomagnetic excursion (∼125 ka) measured in three cores from Ocean Drilling Program (ODP) Site 1062 on the Blake-Bahama Outer Ridge. The Blake excursion has a controversial structure and timing but these cores have a sufficiently high sedimentation rate (∼10 cm ka-1) to allow detailed reconstruction of the field behaviour at this site during the excursion. Palaeomagnetic measurements of the cores reveal rapid transitions (<500 yr) between the contemporary stable normal polarity and a completely reversed state of long duration which spans a stratigraphic interval of 0.7 m. We determine the duration of the reversed state during the Blake excursion using oxygen isotope stratigraphy, combined with 230Th excess measurements to assess variations in the sedimentation rates through the sections of interest. This provides an age and duration for the Blake excursion with greater accuracy and with constrained uncertainty. We date the directional excursion as falling between 129 and 122 ka with a duration for the deviation of 6.5±1.3 kyr. The long duration of this interval and the fully reversed field suggest the existence of a pseudo-stable, reversed dipole field component during the excursion and challenge the idea that excursions are always of short duration.

  20. Response of diatom and silicoflagellate assemblages in the central Gulf of California to regional climate change during the past 55 kyrs

    USGS Publications Warehouse

    Barron, John A.; Bukry, David; Cheshire, Heather

    2014-01-01

    High-resolution studies of diatoms and silicoflagellates of the past 55 kyrs in cores MD02-2517/2515 from the central Gulf of California (GoC) reveal profound changes in GoC surface waters. Roperia tesselata, a diatom proxy for late winter–early spring upwelling, and Dictyocha stapedia, a subtropical silicoflagellate indicative of GoC sea surface temperatures (SSTs) > 24 °C, are common during the Holocene but rare during Marine Isotope Stage (MIS) 2 and most of MIS 3, a relationship that likely reflects a more northerly position of the North Pacific High (NPH) during the Holocene. In contrast during most of MIS 2 (~ 27–15 ka), the persistent presence of Distephanus speculum, a silicoflagellate associated with SSTs During MIS 3 (~ 55–27 ka), increased dominance of Azpeitia nodulifera (diatom) implies that stratified, tropical waters were present year round, whereas silicoflagellate assemblages suggest that stratified tropical conditions alternated with more productive, upwelling conditions on millennial timescales. Reduced biosiliceous productivity during Heinrich events likely reflected a reduction in both surface water nutrient levels and in the strength of northwest winds due to a weakened and more southerly NPH. Conversely, enhanced biosiliceous productivity during MIS 3 interstadials was probably linked to heightened nutrient levels and a strengthened NPH. Abrupt relative abundance increases of the silicoflagellate, Dictyocha aculeata, approximate the termination of MIS3 Heinrich events and may signal times when nutrient-rich deep waters associated with the resumption of enhanced Atlantic Meridional Overturning Circulation penetrated into the central Gulf.

  1. A ~600 kyr duration Early Pleistocene record from the West Turkana (Kenya) HSPDP drill site: elemental XRF variability to reconstruct climate change in Turkana Boy's backyard

    NASA Astrophysics Data System (ADS)

    Stockhecke, M.; Beck, C. C.; Brown, E. T.; Cohen, A.; Deino, A. L.; Feibel, C. S.; Sier, M.

    2015-12-01

    . In addition, the XRF record of the changing hydroclimate of the West Turkana Basin from 1.3 to 1.9 kyrs will be explored in relation to regional reconstructions and marine stratigraphies.

  2. Phytoliths Used to Investigate the Effects of the Indonesian Mount Toba Super-Eruption (~75 kyr) in East Africa: A Subdecadal Record from Lake Malawi

    NASA Astrophysics Data System (ADS)

    Yost, C. L.; Cohen, A. S.

    2014-12-01

    The recent discovery of cryptotephra visually and chemically matched to the Youngest Toba Tuff (YTT, 75.0 ± 0.9 kyr) in Lake Malawi drill core sediments has spurred renewed interest in this period of time in East Africa. The YTT is the most recent and largest of the four Mount Toba eruptions, and is the only super-eruption to have taken place during the Quaternary. The timing of the YTT approximately coincides with a hypothesized human genetic bottleneck. Several climate models have proposed an episode of global cooling following the YTT; however, the magnitude and duration of the cooling is much debated, ranging from just a few degrees of cooling to a state of volcanic winter. Cored sediments from Lake Malawi provide an excellent record of local variability in the lake's watershed that may be linked to specific climatic events. To investigate the possible effects of the YTT in East Africa, we continuously sampled Lake Malawi drill core 2A-10H-2 at 2-4 mm (~6 yr) intervals above and below the first occurrence of the YTT. Poaceae phytoliths were grouped into plant functional types (C3, C4, xerophytic, mesophytic, arboreal, etc.), revealing mostly subtle changes in terrestrial vegetation over the ~400 yr time period examined. Abrupt increases in concentration values for phytoliths derived from riverine Podostemaceae plants appear to signal increased discharge from rivers draining the surrounding uplands. Perhaps most significant is the increasing trend in burned phytoliths and decreasing trend in tree phytoliths post-YTT. Although there appears to be a very weak cooling signal synchronous with the YTT, the most abrupt terrestrial vegetation changes appear to be better correlated with the deposition of a slightly older cryptotephra horizon derived from the local Rungwe Volcanic Province. A potential complication with this record is the existence of a turbidite pre-YTT that encompasses the Rungwe horizon.

  3. Planktic foraminiferal responses to orbital scale oceanographic changes off the western Iberian margin over the last 900 kyr: Results from IODP site U1391

    NASA Astrophysics Data System (ADS)

    Singh, A. D.; Verma, K.; Jaiswal, S.; Alonso-Garcia, M.; Li, B.; Abrantes, F.

    2015-12-01

    This paper presents planktic foraminiferal assemblage records of the last 900 kyr from the SW Iberian margin (IODP Site U1391). The faunal records show the history of surface oceanographic changes on glacial/interglacial scales before and after the Mid-Brunhes Event (MBE), a period when a major shift in the climate pattern was recorded in other regions. Temporal variations in relative abundances of characteristic species/groups are used to infer changes in the latitudinal position of the polar/Arctic water (% Neogloboquadrina pachyderma sinistral and Turborotalita quinqueloba), influence of the transitional subpolar water mass (% N. pachyderma dextral), and subtropical water (% tropical/subtropical species/group). Past changes in the upwelling intensity and productivity pattern associated with seasonal trade wind strength are inferred from the abundance variations of Globigerina bulloides and G. bulloides + Globigerinita glutinata, respectively. Faunal data reveal the influence of cold water masses (polar/subpolar) at the examined site was more pronounced during glacial stages except for marine isotope stage (MIS) 14 and 16. The magnitude of the polar/subpolar water mass invading the study area was at maximum before the MBE during MIS 18, 20 and 22, resulting in a situation like the present day Arctic Front. Interglacial periods prior to the MBE were also relatively colder than those of the post-MBE. Our faunal based inferences are in agreement with the ice-rafted debris (IRD) concentration and N. pachyderma sinistral records of the subpolar North Atlantic sites. Based on faunal proxies, we recorded major and rapid changes in upwelling intensity and related productivity during glacial Terminations. Both the upwelling intensity and productivity significantly increased after the MBE, particularly during the interglacials MIS 7, 9 and 11. Our productivity record parallels the EPICA CH4 record suggesting teleconnections between trade winds induced productivity and the

  4. THE AKARI 2.5-5.0 μm SPECTRAL ATLAS OF TYPE-1 ACTIVE GALACTIC NUCLEI: BLACK HOLE MASS ESTIMATOR, LINE RATIO, AND HOT DUST TEMPERATURE

    SciTech Connect

    Kim, Dohyeong; Im, Myungshin; Kim, Ji Hoon; Jun, Hyunsung David; Lee, Seong-Kook; Woo, Jong-Hak; Lee, Hyung Mok; Lee, Myung Gyoon; Nakagawa, Takao; Matsuhara, Hideo; Wada, Takehiko; Takagi, Toshinobu; Oyabu, Shinki; Ohyama, Youichi E-mail: mim@astro.snu.ac.kr

    2015-01-01

    We present 2.5-5.0 μm spectra of 83 nearby (0.002 < z < 0.48) and bright (K < 14 mag) type-1 active galactic nuclei (AGNs) taken with the Infrared Camera on board AKARI. The 2.5-5.0 μm spectral region contains emission lines such as Brβ (2.63 μm), Brα (4.05 μm), and polycyclic aromatic hydrocarbons (3.3 μm), which can be used for studying the black hole (BH) masses and star formation activity in the host galaxies of AGNs. The spectral region also suffers less dust extinction than in the ultra violet (UV) or optical wavelengths, which may provide an unobscured view of dusty AGNs. Our sample is selected from bright quasar surveys of Palomar-Green and SNUQSO, and AGNs with reverberation-mapped BH masses from Peterson et al. Using 11 AGNs with reliable detection of Brackett lines, we derive the Brackett-line-based BH mass estimators. We also find that the observed Brackett line ratios can be explained with the commonly adopted physical conditions of the broad line region. Moreover, we fit the hot and warm dust components of the dust torus by adding photometric data of SDSS, 2MASS, WISE, and ISO to the AKARI spectra, finding hot and warm dust temperatures of ∼1100 K and ∼220 K, respectively, rather than the commonly cited hot dust temperature of 1500 K.

  5. Marine04 Marine radiocarbon age calibration, 26 ? 0 ka BP

    SciTech Connect

    Hughen, K; Baille, M; Bard, E; Beck, J; Bertrand, C; Blackwell, P; Buck, C; Burr, G; Cutler, K; Damon, P; Edwards, R; Fairbanks, R; Friedrich, M; Guilderson, T; Kromer, B; McCormac, F; Manning, S; Bronk-Ramsey, C; Reimer, P; Reimer, R; Remmele, S; Southon, J; Stuiver, M; Talamo, S; Taylor, F; der Plicht, J v; Weyhenmeyer, C

    2004-11-01

    New radiocarbon calibration curves, IntCal04 and Marine04, have been constructed and internationally ratified to replace the terrestrial and marine components of IntCal98. The new calibration datasets extend an additional 2000 years, from 0-26 ka cal BP (Before Present, 0 cal BP = AD 1950), and provide much higher resolution, greater precision and more detailed structure than IntCal98. For the Marine04 curve, dendrochronologically dated tree-ring samples, converted with a box-diffusion model to marine mixed-layer ages, cover the period from 0-10.5 ka cal BP. Beyond 10.5 ka cal BP, high-resolution marine data become available from foraminifera in varved sediments and U/Th-dated corals. The marine records are corrected with site-specific {sup 14}C reservoir age information to provide a single global marine mixed-layer calibration from 10.5-26.0 ka cal BP. A substantial enhancement relative to IntCal98 is the introduction of a random walk model, which takes into account the uncertainty in both the calendar age and the radiocarbon age to calculate the underlying calibration curve. The marine datasets and calibration curve for marine samples from the surface mixed layer (Marine04) are discussed here. The tree-ring datasets, sources of uncertainty, and regional offsets are presented in detail in a companion paper by Reimer et al.

  6. Maximizing MST's inductive capability with a Bp programmable power supply

    NASA Astrophysics Data System (ADS)

    Chapman, B. E.; Holly, D. J.; Jacobson, C. M.; McCollam, K. J.; Morin, J. C.; Sarff, J. S.; Squitieri, A.

    2016-10-01

    A major goal of the MST program is the advancement of inductive control for the development of both the RFP's fusion potential and, synergistically, the predictive capability of fusion science. This entails programmable power supplies (PPS's) for the Bt and Bp circuits. A Bt PPS is already in place, allowing advanced RFP operation and the production of tokamak plasmas, and a Bp PPS prototype is under construction. To explore some of the new capabilities to be provided by the Bp PPS, the existing Bt PPS has been temporarily connected to the Bp circuit. One key result is new-found access to very low Ip (20 kA) and very low Lundquist number, S (104). At this low S, simulation of RFP plasmas with the MHD code NIMROD is readily achievable, and work toward validation of extended MHD models using NIMROD is underway with direct comparisons to these MST plasmas. The full Bp PPS will also provide higher Ip and S than presently possible, allowing MST to produce plasmas with S spanning as much as five orders of magnitude, a dramatic extension of MST's capability. In these initial tests, the PPS has also increased five-fold MST's Ip flattop duration, to about 100 ms. This, coupled with the recently demonstrated PPS ability to drive large-amplitude sinusoidal oscillations in Ip, will allow tests of extended-duration oscillating field current drive, the goal of which is ac sustainment of a quasi-dc plasma current. Work supported by US DOE.

  7. Thermodynamic properties of underdoped YBa2Cu3O6+x cuprates for doping values x ∈ (0 . 5 , 0 . 9)

    NASA Astrophysics Data System (ADS)

    Salas, P.; Solis, M. A.; Fortes, M.

    We extend the Boson-Fermion superconductivity model to include layered systems, such as underdoped cuprate superconductors YBa2Cu3O6+x, with x ∈ (0 . 5 , 0 . 9) ranging from underdoped to optimally doped. We model cuprates as a boson-fermion quantum gas mixture immersed in a layered structure, generated via a Dirac comb potential applied in one direction while the particles move freely in the other two directions. The optimum parameters of the system, which are the impenetrability of the planes and the paired fermion fraction, are obtained by minimizing the Helmholtz free energy and setting the experimental critical temperature Tc. Using this optimized scheme, we are able to predict the following thermodynamic properties of cuprates as a function of temperature: the entropy; the Helmholtz free energy; the electronic specific heat and the total specific heat for different doping values. Furthermore, we determinate the behavior of the jump height in the electronic specific heat, the normal electronic specific heat coefficient γ (Tc) , the quadratic α and cubic β terms of the specific heat for low temperatures, the ground state energy and the mass anisotropy as a function of doping. Comparison to experimental values reported is analyzed. We aknowledge the support from Grants UNAM-DGAPA-PAPIIT IN-111613 and CONACYT 221030, Mexico.

  8. Velocity Change in the Zone of a Moderate Mw 5.0 Earthquake Revealed by Autocorrelations of Ambient Noise and by Event Spectra

    NASA Astrophysics Data System (ADS)

    von Seggern, David H.; Anderson, John G.

    2017-03-01

    A moderate Mw 5.0 earthquake occurred near Mogul, Nevada (just west of Reno, Nevada), on 26 April 2008. This mainshock was surrounded by notable foreshock and aftershock sequences. Due to the long foreshock sequence, the area was well instrumented at the time of the mainshock. We investigated the foreshock and aftershock sequences for evidence of velocity changes in the structure immediate to the hypocenter and above it in the area of observed strong ground motion. Using autocorrelations of the time periods with nearly continuous foreshocks and aftershocks, we detected a nearly 1% negative change in velocity on recordings of station MOGL which was approximately over the hypocenter of the mainshock. We also observed from these recordings a shift in the spectral peaks to lower frequency following the mainshock, again indicative of a velocity decrease. Due to the different spatial sampling of the two methods, the effects could not be attributed to the same subsurface volume. However, both results are strong evidence for coseismic velocity changes accompanying an earthquake which is very much smaller than those for which previous velocity changes have been reported. We hypothesize that these changes can be observed for even smaller earthquakes, given a fortuitous placement of observing stations.

  9. The GEOS-5 Data Assimilation System-Documentation of Versions 5.0.1, 5.1.0, and 5.2.0

    NASA Technical Reports Server (NTRS)

    Suarez, Max J.; Rienecker, M. M.; Todling, R.; Bacmeister, J.; Takacs, L.; Liu, H. C.; Gu, W.; Sienkiewicz, M.; Koster, R. D.; Gelaro, R.; Stajner, I.; Nielsen, J. E.

    2008-01-01

    This report documents the GEOS-5 global atmospheric model and data assimilation system (DAS), including the versions 5.0.1, 5.1.0, and 5.2.0, which have been implemented in products distributed for use by various NASA instrument team algorithms and ultimately for the Modem Era Retrospective analysis for Research and Applications (MERRA). The DAS is the integration of the GEOS-5 atmospheric model with the Gridpoint Statistical Interpolation (GSI) Analysis, a joint analysis system developed by the NOAA/National Centers for Environmental Prediction and the NASA/Global Modeling and Assimilation Office. The primary performance drivers for the GEOS DAS are temperature and moisture fields suitable for the EOS instrument teams, wind fields for the transport studies of the stratospheric and tropospheric chemistry communities, and climate-quality analyses to support studies of the hydrological cycle through MERRA. The GEOS-5 atmospheric model has been approved for open source release and is available from: http://opensource.gsfc.nasa.gov/projects/GEOS-5/GEOS-5.php.

  10. Gum arabic and Fe²⁺ synergistically improve the heat and acid stability of norbixin at pH 3.0-5.0.

    PubMed

    Guan, Yongguang; Zhong, Qixin

    2014-12-31

    Thermal and acid stabilities of norbixin are challenges for its application as a food colorant. In this work, gum arabic and Fe(2+) were studied for the possibility to improve the thermal and acid stabilities of norbixin. Norbixin was dissolved at 0.004% w/v in deionized water with and without 0.2% w/v gum arabic and/or 0.15 mM ferrous chloride, adjusted to pH 3.0-5.0, and heated at 90 or 126 °C for 30 min. Before heating, norbixin precipitated at pH 3.0-4.0, which was prevented by gum arabic. The thermal stability of norbixin was improved by the combination of gum arabic and Fe(2+). Fluorescence analyses indicated the complex formation between norbixin and gum arabic with and without Fe(2+). Particle size and atomic force microscopy results suggested Fe(2+) and gum arabic synergistically prevented the aggregation of norbixin at acidic pH and during heating. It was hypothesized that the core of gum arabic-norbixin complexes was strengthened by Fe(2+) to enable the synergy.

  11. The M w 5.0 Hammam Melouane Earthquake (North Central Algeria) of 17 July 2013 in the Context of the Tellian Atlas Seismicity

    NASA Astrophysics Data System (ADS)

    Yelles-Chaouche, A. K.; Haned, A.; Aidi, C.; Beldjoudi, H.; Kherroubi, A.; Semmane, F.; Benabdeloued, B. Y. N.; Larbes, Y.; Alili, A.; Khelif, M. F.; Belheouane, A.

    2017-02-01

    On 17 July 2013 (03:00 GMT) a new moderate earthquake of magnitude 5.0 happened in the Tell belts of northern Algeria, more precisely near the village of Hammam Melouane (Algeria), 30 km south of Algiers, the Capital of Algeria. The main shock parameters and aftershocks activity analysis, reveal that the earthquake occurred on a 5 km long dextral strike-slip fault oriented N114°E, a conjugate strike-slip fault of the major NE-SW reverse fault system of the neogene Mitidja basin. This event caused damage to houses and social infrastructures but no fatalities were reported. Onland the earthquake triggered rock falls and minor landslides along the Hammam Melouane river. The occurrence of the Hammam Melouane in the northern limit of the Tell belts is representative of the African-Eurasiatic interplate seismicity of northern Algeria where major seismic events could occurred as the previous Boumerdes event of May 21st, 2003 (M w 6.8).

  12. Preliminary Geological Findings on the BP-1 Simulant

    NASA Technical Reports Server (NTRS)

    Stoeser, D. B.; Rickman, D. L.; Wilson, S.

    2010-01-01

    A waste material from an aggregate producing quarry has been used to make an inexpensive lunar simulant called BP-1. The feedstock is the Black Point lava flow in northern Arizona. Although this is part of the San Francisco volcanic field, which is also the source of the JSC-1 series feedstock, BP-1 and JSC-1 are distinct. Chemically, the Black Point flow is an amygdaloidal nepheline-bearing basalt. The amygdules are filled with secondary minerals containing opaline silica, calcium carbonate, and ferric iron minerals. X-ray diffraction (XRD) detected approximately 3% quartz, which is in line with tests done by the Kennedy Space Center Industrial Hygiene Office. Users of this material should use appropriate protective equipment. XRD also showed the presence of significant halite and some bassanite. Both are interpreted to be evaporative residues due to recycling of wash water at the quarry. The size distribution of BP-1 may be superior to some other simulants for some applications.

  13. Preliminary Geological Findings on the BP-1 Simulant

    NASA Technical Reports Server (NTRS)

    Rickman, D. L.

    2010-01-01

    The following is a summation of information and discussion between Doug Stoeser of the USGS and Doug Rickman of NASA in February and March, 2010 pertaining to the BP-1 simulant. The analytical results and the bulk of the text are from communications from Dr. Stoeser. The BP-1 simulant is made from Black Point Basalt Flow, San Francisco Volcanic Field, northern Arizona. There is an aggregate (road metal) quarry on the northern margin of the flow towards the west end that was used as a Desert Research and Technology Studies (Desert RATS) analog test site. Silty material from this site was also used in laboratory tests and found to have geotechnical properties similar to the LHT-2M and Chenobi regolith simulants and is being proposed as a possible simulant for geotechnical use. It currently has the designation of BP-1 (Black Point 1). Figure

  14. A 400-kyr record of millennial-scale carbonate preservation events in the Southern Ocean: Implications for Atlantic Meridional Overturning Circulation and atmospheric CO2

    NASA Astrophysics Data System (ADS)

    Hodell, D. A.; Vautravers, M. J.; Barker, S.; Charles, C.; Crowhurst, S.

    2014-12-01

    Hodell et al. (2001) suggested that carbonate preservation in the deep Cape Basin represented a qualitative, high-resolution record of the temporal evolution of the carbonate saturation state of the deep sea. The carbonate signal reflects both transient events in the redistribution of alkalinity and DIC in the deep ocean and steady-state mass balance processes. Here we re-analyzed the carbonate records of Sites 1089/TN057-21 using an Avaatech XRF core scanner and measured elemental variations at 2.5-mm resolution for the past 400 kyrs. Log Ca/Ti is highly correlated to weight percent carbonate content and other dissolution proxies and resolves millennial-scale events in carbonate preservation. A high-pass filter removes the low-frequency (orbital) variability in carbonate preservation, which is attributed mainly to steady-state mass balance processes. The high-frequency (suborbital) component reflects transient responses to the redistribution of carbonate ion that is related mainly to changing deep-water circulation. During the last glacial period, distinct millennial-scale increases in carbonate preservation in piston core TN057-21 occurred during times of enhanced Atlantic Meridional Overtunring Circulation (AMOC) (Barker et al., 2010; Barker and Diz, 2014), as supported by increases in benthic δ13C and less radiogenic ɛNd values. Carbonate preservation peaked particularly during long, warm interstadials in Greenland when a deep water mass with high carbonate ion concentration was formed in the North Atlantic. Export of NADW may have been greater than the Holocene during some of these events ("overshoots") and/or preformed carbonate ion concentrations in North Atlantic source areas may have been higher owing to lower atmospheric CO2 and less carbonate production in surface water. Each South Atlantic carbonate peak is associated with the start of Antarctic cooling and declining or leveling of atmospheric CO2, reflecting the signature of a thermal bipolar seesaw

  15. Change in Mediterranean Hydrologic Cycle at Time of Heinrich Events From a High Resolution Multiproxy Record of the Last 50 kyr

    NASA Astrophysics Data System (ADS)

    Bout-Roumazeilles, V.; Combourieu Nebout, N.; Peyron, O.; Dormoy, I.

    2008-12-01

    Clay mineralogy, pollen record and pollen-based reconstructions were performed over the last climatic cycle on the Site ODP 976 (Alboran Sea, Western Mediterranean). These proxies show that several droughts occurred during the past 50 kyr. Enhanced contribution of wind-blown palygorskite and development of the semi-arid vegetation (Artemisia rich) occurs during the North Atlantic Cold climatic events (Heinrich events). The peculiar clay mineral association and the presence of Argania pollen grains pinpoint Western Morocco as a major source for wind-blown particles during the Heinrich events. Clay mineral and pollen associations indicate the development of semi-desert environment and the intensification of winds favoring dust erosion and transport from Sahara toward the Alboran Sea during the North Atlantic Heinrich events. Quantitative climate reconstructions performed on the ODP976 pollen record have yielded the reconstruction of ombrothermic diagrams for past key periods. They reveal that annual precipitations regime in the west Mediterranean area were rather different during Heinrich events than today with drastic drought during the whole year. As a comparison, the reconstructed Holocene and stadials annual climatic cycles are very similar to present-day distribution, with dry conditions restricted to summertime. During these cold climatic events, the drastic fall in both precipitations and temperatures suggest cold and arid continental conditions in the West Mediterranean area. These regions were suffering from reduced precipitations not only during winter but also during spring and fall usually experiencing wet conditions. Such a major modification, with repetitive cold and dry-conditions in both winter and spring, should have deeply affected the development of temperate forest -sensitive to precipitation amount- and of the Mediterranean forest which lives under warm-dry summer and mild-humid winter conditions. These clay- and pollen-based reconstructions

  16. Clay mineral contribution from various provenances in the northern South China Sea over the past 400 kyr: implications for the East Asian monsoon evolution

    NASA Astrophysics Data System (ADS)

    Chen, Quan; Liu, Zhifei; Xie, Xin; Kissel, Catherine

    2014-05-01

    Clay mineralogy of Core MD12-3432 taken at 2125 m water depth (CIRCEA cruise on board the R.V. Marion Dufresne, IPEV) in the northern South China Sea was investigated in order to understand the time series contribution of terrigenous sediments from various provenances. With calibration of a low-resolution analysis on carbonate concentration and major elements, we converted the XRF core scanned calcium data into a high-resolution carbonate content records. Through referring to the well-dated carbonate record of nearby Core MD05-2904, we established a reliable age model, indicating about 400 kyr ago at the bottom of Core MD12-3432. The clay mineral assemblage is dominated by smectite (23-59%) and illite (22-43%), with minor chlorite (13-27%) and kaolinite (4-13%). The time series variation of clay mineral assemblages indicates strong glacial-interglacial cyclicity. In general, the variation in smectite content is similar to that of carbonate concentration, with higher values during interglacials than during glacials, while illite and chlorite contents showing opposite patterns. The change in kaolinite content shows an independent pattern with high values during glacials, corresponding well with the illite crystallinity variation. The provenance analysis of these clay minerals suggests three end-member sources: all smectites derive from Luzon, all kaolinites originate from the Pearl River, and illite and chlorite are coming from both the Pearl River and Taiwan. Using the linear separation method of illite crystallinity, a time series of the clay mineral contribution from the three major provenances to the northern South China Sea was reconstructed. Combined with spectral analyses, we suggest the clay mineral contribution from Pearl River was mainly influenced by sea level change, while the East Asian summer monsoon controlled the contribution from Luzon. The strong precipitation rate related to intensive East Asian summer monsoon would have enhanced the denudation and

  17. Neodymium isotopic composition in foraminifera and authigenic phases of the South China Sea sediments: Implications for the hydrology of the North Pacific Ocean over the past 25 kyr

    NASA Astrophysics Data System (ADS)

    Wu, Qiong; Colin, Christophe; Liu, Zhifei; Thil, François; Dubois-Dauphin, Quentin; Frank, Norbert; Tachikawa, Kazuyo; Bordier, Louise; Douville, Eric

    2015-11-01

    ɛNd and normalized Rare Earth Elements (REE) patterns of benthic and planktonic foraminifera and Fe-Mn coatings precipitated on sediments have been investigated for the South China Sea (SCS) to (1) assess the reliability of the extraction of past seawater ɛNd in the SCS and to (2) reconstruct past hydrological changes during the last 25 kyr. Reductively cleaned mono-specific planktonic foraminifera (Globigerinoides ruber) and mixed benthic foraminifera in core-top sediments from 1500 to 2400 m display similar ɛNd values to those of the modern Pacific Deep Water (PDW) (ɛNd of -3.9 to -4.4). Furthermore, the ɛNd of the reductive cleaning solutions shows similar ɛNd values to ones obtained on cleaned foraminifera. Combined with PAAS-normalized REE patterns, these results confirm that the oxidative and reductive cleaning procedure applied to foraminifera does not totally remove all of the Fe-Mn coatings and that ɛNd values yielded by cleaned planktonic foraminifera retain the ɛNd imprint of the bottom and/or pore water. ɛNd values obtained from a leaching procedure carried out on the bulk non-decarbonated sediments are comparable to the ɛNd values of the modern PDW, whereas a similar leaching procedure applied to decarbonated sediments reveals a bias due to contamination with Nd deriving from lithogenic particles. In core MD05-2904, seawater ɛNd, reconstructed from planktonic foraminifera, indicates that the last glacial period is characterized by lower ɛNd (-5.2 ± 0.2 to -6.4 ± 0.3) than the late Holocene (-4.1 ± 0.2). Assuming that Nd input from river does not change strongly the ɛNd of the PDW of the northern SCS, these ɛNd variations suggest a higher relative proportions of southern-sourced water in the deep water of the western subtropical Pacific Ocean during the last glacial period.

  18. 200-BP-5 operable unit treatability test report

    SciTech Connect

    1996-04-01

    The 200-BP-5 Operable Unit was established in response to recommendations presented in the 200 East Groundwater Aggregate Area Management Study Report (AAMSR) (DOE-RL 1993a). Recognizing different approaches to remediation, the groundwater AAMSR recommended separating groundwater from source and vadose zone operable units and subdividing 200 East Area groundwater into two operable units. The division between the 200-BP-5 and 200-PO-1 Operable Units was based principally on source operable unit boundaries and distribution of groundwater plumes derived from either B Plant or Plutonium/Uranium Extraction (PUREX) Plant liquid waste disposal sites.

  19. Computationally efficient air quality forecasting tool: implementation of STOPS v1.5 model into CMAQ v5.0.2 for a prediction of Asian dust

    NASA Astrophysics Data System (ADS)

    Jeon, Wonbae; Choi, Yunsoo; Percell, Peter; Souri, Amir Hossein; Song, Chang-Keun; Kim, Soon-Tae; Kim, Jhoon

    2016-10-01

    This study suggests a new modeling framework using a hybrid Eulerian-Lagrangian-based modeling tool (the Screening Trajectory Ozone Prediction System, STOPS) for a prediction of an Asian dust event in Korea. The new version of STOPS (v1.5) has been implemented into the Community Multi-scale Air Quality (CMAQ) model version 5.0.2. The STOPS modeling system is a moving nest (Lagrangian approach) between the source and the receptor inside the host Eulerian CMAQ model. The proposed model generates simulation results that are relatively consistent with those of CMAQ but within a comparatively shorter computational time period. We find that standard CMAQ generally underestimates PM10 concentrations during the simulation period (February 2015) and fails to capture PM10 peaks during Asian dust events (22-24 February 2015). The underestimation in PM10 concentration is very likely due to missing dust emissions in CMAQ rather than incorrectly simulated meteorology, as the model meteorology agrees well with the observations. To improve the underestimated PM10 results from CMAQ, we used the STOPS model with constrained PM concentrations based on aerosol optical depth (AOD) data from the Geostationary Ocean Color Imager (GOCI), reflecting real-time initial and boundary conditions of dust particles near the Korean Peninsula. The simulated PM10 from the STOPS simulations were improved significantly and closely matched the surface observations. With additional verification of the capabilities of the methodology on emission estimations and more STOPS simulations for various time periods, the STOPS model could prove to be a useful tool not just for the predictions of Asian dust but also for other unexpected events such as wildfires and oil spills.

  20. AKARI observations of brown dwarfs. IV. Effect of elemental abundances on near-infrared spectra between 1.0 and 5.0 μm

    SciTech Connect

    Sorahana, S.; Yamamura, I.

    2014-09-20

    The detection of the CO{sub 2} absorption band at 4.2 μm in brown dwarf spectra by AKARI has made it possible to discuss CO{sub 2} molecular abundance in brown dwarf atmospheres. In our previous studies, we found an excess in the 4.2 μm CO{sub 2} absorption band of three brown dwarf spectra, and suggested that these deviations were caused by high C and O elemental abundances in their atmospheres. To validate this hypothesis, we have constructed a set of models of brown dwarf atmospheres with various elemental abundance patterns, and we investigate the variations of the molecular composition and the thermal structure, and how they affect the near-infrared spectra between 1.0 and 5.0 μm. The 4.2 μm CO{sub 2} absorption band in some late-L and T dwarfs taken by AKARI is stronger or weaker than predicted by corresponding models with solar abundance. By comparing the CO{sub 2} band in the model spectra to the observed near-infrared spectra, we confirm possible elemental abundance variations among brown dwarfs. We find that the band strength is especially sensitive to O abundance, but C is also needed to reproduce the entire near-infrared spectra. This result indicates that both the C and O abundances should increase and decrease simultaneously for brown dwarfs. We find that a weaker CO{sub 2} absorption band in a spectrum can also be explained by a model with lower 'C and O' abundances.

  1. The Role of Multiple Foreshock Structures in Facilitating the Rupture of the Mw 5.0 Earthquake Swarm Mainshock near Urban Reno, Nevada in 2008

    NASA Astrophysics Data System (ADS)

    Ruhl, C. J.; Smith, K. D.; Abercrombie, R. E.

    2014-12-01

    We resolve complex spatial and temporal evolution of a long-duration earthquake sequence on multiple fault planes by combining high-precision relative relocations with over 350 first-motion focal mechanisms and applying physics-based, open-source software supported by both the USGS and CIG (Computational Infrastructure in Geodynamics) to investigate static and quasi-static stress changes during an 8 week foreshock period. Low-magnitude earthquake activity began on February 28, 2008 in the Mogul neighborhood west of urban Reno, NV and continued to build in intensity leading to the MW 5.0 mainshock on April 26, 2008. Initial locations are obtained by applying station and datum corrections to analyst-picked travel times using HYPOINVERSE then relocating the sequence via the HypoDD double-difference algorithm of Waldhauser and Ellsworth (2000) using both cross-correlated and catalog phase data on P and S arrivals. The final relocation set reveals a mechanism-supported temporal and spatial migration of seismicity on several distinct structures prior to the mainshock rupture. First-motion focal mechanisms are computed using the HASH code of Hardebeck and Shearer (2002). We apply the spatial and temporal stress inversion (SATSI) software (Hardebeck and Michael, 2006) to investigate variations in the stress field throughout the sequence. We integrate preliminary analysis of stress drops (ML ≥ 3.0) using an EGF-derived spectral ratio technique. Finally, we determine significant fault planes identified in the foreshock sequence and build a local 3D fault model. We systematically test various slip scenarios on these structures using both CIG's finite-element crustal deformation code PyLith and the USGS-supported Coulomb 3 program to explore how the foreshocks promote or inhibit failure on subsequent structures that may facilitate mainshock rupture.

  2. ITS version 5.0 :the integrated TIGER series of coupled electron/Photon monte carlo transport codes with CAD geometry.

    SciTech Connect

    Franke, Brian Claude; Kensek, Ronald Patrick; Laub, Thomas William

    2005-09-01

    ITS is a powerful and user-friendly software package permitting state-of-the-art Monte Carlo solution of linear time-independent coupled electron/photon radiation transport problems, with or without the presence of macroscopic electric and magnetic fields of arbitrary spatial dependence. Our goal has been to simultaneously maximize operational simplicity and physical accuracy. Through a set of preprocessor directives, the user selects one of the many ITS codes. The ease with which the makefile system is applied combines with an input scheme based on order-independent descriptive keywords that makes maximum use of defaults and internal error checking to provide experimentalists and theorists alike with a method for the routine but rigorous solution of sophisticated radiation transport problems. Physical rigor is provided by employing accurate cross sections, sampling distributions, and physical models for describing the production and transport of the electron/photon cascade from 1.0 GeV down to 1.0 keV. The availability of source code permits the more sophisticated user to tailor the codes to specific applications and to extend the capabilities of the codes to more complex applications. Version 5.0, the latest version of ITS, contains (1) improvements to the ITS 3.0 continuous-energy codes, (2) multigroup codes with adjoint transport capabilities, (3) parallel implementations of all ITS codes, (4) a general purpose geometry engine for linking with CAD or other geometry formats, and (5) the Cholla facet geometry library. Moreover, the general user friendliness of the software has been enhanced through increased internal error checking and improved code portability.

  3. The binary Cepheid BP CIR - A test of evolutionary tracks

    NASA Astrophysics Data System (ADS)

    Evans, Nancy R.; Arellano Ferro, A.; Udalska, Joanna

    1992-05-01

    IUE spectra of the system containing the Cepheid BP Cir are used to derive the magnitude difference between the two stars (Δ V = 1.88 ± 0.3 mag) and the spectral type of the companion (B6.OV). This is the first system yet encountered for which the standard Seaton reddening law is inappropriate. For BP Cir, a stronger 2200 Å bump than the standard law is required. However, this does not affect the determination of the temperature of the hot star or the magnitude difference between the two stars, because those use the wavelength regions shorter than 1600 Å and longer than 2500 Å. The stars are very similar in mass. Possible pulsation in the first overtone mode implies that BP Cir B is evolved beyond the ZAMS but is still in the main sequence band. The best match to BP Cir A and B is with isochrones by Stothers and Chin (1991) with Inglesias and Rogers (1991) opacities and no core convective overshoot and Cepheid pulsation in the first overtone.

  4. The binary Cepheid BP Cir - A test of evolutionary tracks

    NASA Technical Reports Server (NTRS)

    Evans, Nancy R.; Ferro, A. A.; Udalska, Joanna

    1992-01-01

    IUE spectra of the system containing the Cepheid BP Cir are used to derive the magnitude difference between the two stars (Delta V = 1.88 +/- 0.3 mag) and the spectral type of the companion (B6.0V). This is the first system yet encountered for which the standard Seaton reddening law is inappropriate. For BP Cir, a stronger 2200-A bump than the standard law is required. However, this does not affect the determination of the temperature of the hot star or the magnitude difference between the two stars, because those use the wavelength regions shorter than 1600 A and longer than 2500 A. The stars are very similar in mass. Possible pulsation in the first overtone mode implies that BP Cir B is evolved beyond the ZAMS but is still in the main sequence band. The best match to BP Cir A and B is with isochrones by Stothers and Chin (1991) with Inglesias and Rogers (1991) opacities and no core convective overshoot and Cepheid pulsation in the first overtone.

  5. BP Piscium: its flaring disc imaged with SPHERE/ZIMPOL★

    NASA Astrophysics Data System (ADS)

    de Boer, J.; Girard, J. H.; Canovas, H.; Min, M.; Sitko, M.; Ginski, C.; Jeffers, S. V.; Mawet, D.; Milli, J.; Rodenhuis, M.; Snik, F.; Keller, C. U.

    2017-03-01

    Whether BP Piscium (BP Psc) is either a pre-main sequence T Tauri star at d ≈ 80 pc, or a post-main sequence G giant at d ≈ 300 pc is still not clear. As a first-ascent giant, it is the first to be observed with a molecular and dust disc. Alternatively, BP Psc would be among the nearest T Tauri stars with a protoplanetary disc (PPD). We investigate whether the disc geometry resembles typical PPDs, by comparing polarimetric images with radiative transfer models. Our Very Large Telescope/Spectro-Polarimetric High-contrast Exoplanet REsearch (SPHERE)/Zurich IMaging Polarimeter (ZIMPOL) observations allow us to perform polarimetric differential imaging, reference star differential imaging, and Richardson-Lucy deconvolution. We present the first visible light polarization and intensity images of the disc of BP Psc. Our deconvolution confirms the disc shape as detected before, mainly showing the southern side of the disc. In polarized intensity the disc is imaged at larger detail and also shows the northern side, giving it the typical shape of high-inclination flared discs. We explain the observed disc features by retrieving the large-scale geometry with MCMAX radiative transfer modelling, which yields a strongly flared model, atypical for discs of T Tauri stars.

  6. TopBP1-mediated DNA processing during mitosis.

    PubMed

    Gallina, Irene; Christiansen, Signe Korbo; Pedersen, Rune Troelsgaard; Lisby, Michael; Oestergaard, Vibe H

    2016-01-01

    Maintenance of genome integrity is crucial to avoid cancer and other genetic diseases. Thus faced with DNA damage, cells mount a DNA damage response to avoid genome instability. The DNA damage response is partially inhibited during mitosis presumably to avoid erroneous processing of the segregating chromosomes. Yet our recent study shows that TopBP1-mediated DNA processing during mitosis is highly important to reduce transmission of DNA damage to daughter cells. (1) Here we provide an overview of the DNA damage response and DNA repair during mitosis. One role of TopBP1 during mitosis is to stimulate unscheduled DNA synthesis at underreplicated regions. We speculated that such genomic regions are likely to hold stalled replication forks or post-replicative gaps, which become the substrate for DNA synthesis upon entry into mitosis. Thus, we addressed whether the translesion pathways for fork restart or post-replicative gap filling are required for unscheduled DNA synthesis in mitosis. Using genetics in the avian DT40 cell line, we provide evidence that unscheduled DNA synthesis in mitosis does not require the translesion synthesis scaffold factor Rev1 or PCNA ubiquitylation at K164, which serve to recruit translesion polymerases to stalled forks. In line with this finding, translesion polymerase η foci do not colocalize with TopBP1 or FANCD2 in mitosis. Taken together, we conclude that TopBP1 promotes unscheduled DNA synthesis in mitosis independently of the examined translesion polymerases.

  7. BP chief scientist nominated for senior energy role

    NASA Astrophysics Data System (ADS)

    Gwynne, Peter

    2014-01-01

    The Obama administration has nominated BP's chief scientist Ellen Williams to be director of the Advanced Research Projects Agency-Energy (ARPA-E), which was created in 2007 to fund "high-risk, high-reward" research into novel energy technologies that are too early for investment by the private sector.

  8. A surface complexation model of YREE sorption on Ulva lactuca in 0.05-5.0 M NaCl solutions

    NASA Astrophysics Data System (ADS)

    Zoll, Alison M.; Schijf, Johan

    2012-11-01

    We present distribution coefficients, log iKS, for the sorption of yttrium and the rare earth elements (YREEs) on BCR-279, a dehydrated tissue homogenate of a marine macroalga, Ulva lactuca, resembling materials featured in chemical engineering studies aimed at designing renewable biosorbents. Sorption experiments were conducted in NaCl solutions of different ionic strength (0.05, 0.5, and 5.0 M) at T = 25 °C over the pH range 2.7-8.5. Distribution coefficients based on separation of the dissolved and particulate phase by conventional filtration (<0.22 μm) were corrected for the effect of colloid-bound YREEs (>3 kDa) using an existing pH-dependent model. Colloid-corrected values were renormalized to free-cation concentrations by accounting for YREE hydrolysis and chloride complexation. At each ionic strength, the pH dependence of the renormalized values is accurately described with a non-electrostatic surface complexation model (SCM) that incorporates YREE binding to three monoprotic functional groups, previously characterized by alkalimetric titration, as well as binding of YREE-hydroxide complexes (MOH2+) to the least acidic one (pKa ∼ 9.5). In non-linear regressions of the distribution coefficients as a function of pH, each pKa was fixed at its reported value, while stability constants of the four YREE surface complexes were used as adjustable parameters. Data for a single fresh U. lactuca specimen in 0.5 M NaCl show generally the same pH-dependent behavior but a lower degree of sorption and were excluded from the regressions. Good linear free-energy relations (LFERs) between stability constants of the YREE-acetate and YREE-hydroxide solution complex and surface complexes with the first and third functional group, respectively, support their prior tentative identifications as carboxyl and phenol. A similar confirmation for the second group is precluded by insufficient knowledge of the stability of YREE-phosphate complexes and a perceived lack of YREE binding

  9. Surface Water Conditions in the Central Gulf of California During the Past 52 Kyrs Based on Diatoms and Silicoflagellates: Implications for Monsoonal Moisture Transport

    NASA Astrophysics Data System (ADS)

    Barron, J. A.; Bukry, D.; Cheshire, H.

    2012-12-01

    Between late fall and early spring persistent northwest winds in the Gulf of California (GoC) cause upwelling of subsurface waters rich in nutrients, resulting in high surface water productivity and the deposition of biogenic silica-rich sediments. Slackening of these winds during the spring leads to progressive northward advection of warmer, more oligotrophic waters. Surges of monsoonal moisture up the axis of the Gulf into the southwestern US begin in July when SSTs in the northern GoC exceed 26°C. Our studies of biogenic SST proxies (diatoms, silicoflagellates, calcium carbonate) reveal that surface waters of the central GoC were too cool between ~10.5 and 7.5 ka (early Holocene) to support northward surges of monsoonal moisture. During this interval, warmer SSTs off the Pacific coast of Baja California appear to have facilitated a more zonal flow of tropical moisture into a geographically broader region of the southwestern US (Barron et al., 2012). High-resolution studies of diatoms and silicoflagellates of the past 52 kyr on well dated cores (MD02-2517/2515) from the central GoC reveal profound changes in GoC surface waters that should have affected the pathways of monsoonal moisture. During Marine Isotope Stage 2 (MIS2), the persistent presence of Distephanus speculum (silicoflagellate) is evidence that the California Current penetrated into the GoC, likely reflecting a southward-shifted Subtropical High pressure cell. Diatoms also suggest an increased presence of cool, low salinity surface waters in the central GoC between ~27 and 18 ka that would not have been conducive to northward surges of monsoonal moisture. The dominance of the diatom Azpeitia nodulifera between 52 and 27 ka is evidence that tropical oligotrophic waters were present year round during MIS3. Silicoflagellates, however, indicate that oligotrophic conditions alternated with lower salinity, subtropical surface waters during MIS3, much as they did during the Holocene. Abrupt increases of

  10. Geochemical multielement signatures of glacial and interglacial facies of the Okhotsk Sea deepwater sediments during the past 350 kyr: A response to global climate changes at the orbital and millennial scales

    NASA Astrophysics Data System (ADS)

    Chebykin, Eugene P.; Gorbarenko, Sergey A.; Stepanova, Ol'ga G.; Panov, Vsevolod S.; Goldberg, Evgeny L.

    2015-03-01

    The previously dated deepwater sediment core MR06-04 PC-7R (length 1723 cm; 350 kyr) recovered from the central Okhotsk Sea (OS) was analyzed for biogenic compounds and for 63 chemical elements (using the inductively coupled plasma-mass spectrometry method) with a high resolution (1 cm; ~200 years). A one box model with two main members" and mathematical methods (based on multielemental composition of sediments) for the calculation of weight fractions (at each time slice) of two main types of geochemical facies that dominate during considerably diverse climatic periods (glacial maxima and interglacial optima) were proposed and tested. This model can be applied to other analogous natural systems whose sedimentation is driven by two main types of geochemical facies. The application of the developed model to the studied core revealed that variations of weight fractions of the typical interglacial and glacial geochemical facies in the sediments along the core depth (named as warm and cold "covariators," respectively) change synchronously with global and regional climate variability. Profiles of warm and inversed cold covariators coincide tightly, and their values increase during warm marine isotope stages and substages and decrease during cold ones over the last 350 kyr. Millennial scale changes in covariators had occurred simultaneously with abrupt variability in the OS productivity and sediment lithology and with millennial global climate variability. Some discrepancies in the warm and inversed cold covariators calculated using specific mathematical treatments revealed the episodic influence of volcanogenic matter presented in the core by visible tephra layers and cryptotephras.

  11. BpTRU(tm) blood pressure monitor for use in a physician's office.

    PubMed

    Allison, C

    2006-08-01

    The BpTRU(tm) is an automated device that takes serial blood pressure (BP) measurements in a physician's office. (1) Preliminary data from non-randomized, uncontrolled trials suggest that the average of five BpTRU measurements, taken while the patient is alone, more reliably reflects "resting" BP compared to manual measurements taken with a stethoscope and sphygmomanometer. (2) BpTRU helps reduce the overestimation of BP due to improper measurement technique, or due to a patient's anxiety in a physician's presence ("white coat" effect). (3) The BpTRU device can improve hypertension management by replacing conventional manual BP measurements, which are often poorly performed and inaccurate. (4) BpTRU is more expensive than the manual manometers used in a physician's office. The serial measurement, taken in a private examining room, requires an average of six to 12 minutes, which could increase the duration of a patient's visit.

  12. Activity on the classical T Tauri star BP Tauri.

    NASA Astrophysics Data System (ADS)

    Gullbring, E.; Barwig, H.; Chen, P. S.; Gahm, G. F.; Bao, M. X.

    1996-03-01

    We have made a detailed investigation of the short-term variability in optical light (UBVRI) of the classical T Tauri star BP Tauri. Photometric data (in UBVRI) were collected from Wendelstein Observatory, Germany in 1991, 1992 and 1993 with time-resolutions down to 1sec and, from binning, fluctuations with total amplitudes down to a few milli-magnitudes could be resolved. Additional observations (in UBV) were collected in China. The total time of monitoring amounts to 135 hours. The normal state of BP Tau is that it stays completely constant in brightness in all bands, or shows only very slow and smooth changes during a night, to the limit of detection. Brightenings, events, occurred on time-scales from 0.6hours to a few hours but none of these reached a total amplitude >0.3mag in U. As a rule these events do not have the characteristic flare profile as in the lightcurves of stellar surface flares. The total optical energies of the events are a few times 10^35^erg, with a relatively small spread. The energy distributions at peak flux can be represented by black-body radiation. However, the inferred temperature is very low, 7000-8000K, and not significantly different from that derived for the background veiling. Hence, the events on BP Tau are very different from normal stellar flares. From power analysis of the time series, we conclude that there is no power indicating frequent and short lasting phenomena, like surface flares. In particular there is no signal in the U band. Such flares would have been expected to be numerous in this high-sensitivity survey, however, if BP Tau had a magnetic surface activity comparable to that of ordinary flare stars. Also, there is no tail in the distribution of events towards smaller amplitudes and shorter durations. We show that the events of BP Tau are consistent with inhomogeneous mass infall from magnetically controlled accretion between a circumstellar disk and a hot spot at the star. To account for the constancy in

  13. Multiple-site mutations of phage Bp7 endolysin improves its activities against target bacteria.

    PubMed

    Zhang, Can; Wang, Yuanchao; Sun, Huzhi; Ren, Huiying

    2015-10-01

    The widespread use of antibiotics has caused serious drug resistance. Bacteria that were once easily treatable are now extremely difficult to treat. Endolysin can be used as an alternative to antibiotics for the treatment of drug-resistant bacteria. To analyze the antibacterial activity of the endolysin of phage Bp7 (Bp7e), a 489-bp DNA fragment of endolysin Bp7e was PCR-amplified from a phage Bp7 genome and cloned, and then a pET28a-Bp7e prokaryotic expression vector was constructed. Two amino acids were mutated (L99A, M102E) to construct pET28a-Bp7Δe, with pET28a-Bp7e as a template. Phylogenetic analysis suggested that BP7e belongs to a T4-like phage endolysin group. Bp7e and its mutant Bp7Δe were expressed in Escherichia coli BL21(DE3) as soluble proteins. They were purified by affinity chromatography, and then their antibacterial activities were analyzed. The results demonstrated that the recombinant proteins Bp7e and Bp7Δe showed obvious antibacterial activity against Micrococcus lysodeikticus but no activity against Staphylococcus aureus. In the presence of malic acid, Bp7e and Bp7Δe exhibited an effect on most E. coli strains which could be lysed by phage Bp7, but no effect on Salmonella paratyphi or Pseudomonas aeruginosa. Moreover, Bp7Δe with double-site mutations showed stronger antibacterial activity and a broader lysis range than Bp7e.

  14. Calibration of the radiocarbon time scale at 37ka BP

    SciTech Connect

    Southon, J.R.; Deino, A.L.; Orsi, G.

    1995-12-01

    Results from radiocarbon and U-Th measurements on corals have provided a radiocarbon calibration beyond the range covered by tree ring series, but the uncertainties in the measurements beyond 20ka BP are very large. We have obtained new calibration data from radiocarbon dates on material associated with the catastrophic Campanian Ignimbrite eruption from the Phlegrean Fields near Naples. The eruption has been well dated by {sup 40}Ar/{sup 39}Ar to 37ka BP. Radiocarbon measurements were carried out on charcoal from a carbonized branch exposed within the ignimbrite tuff on the wall of an active quarry. The sample was split and analyzed at both the Naples and Lawrence Livermore AMS facilities. The offset between the Ar-Ar data and the radiocarbon results (recalculated using the true 5730-year half life for {sup 14}C) is consistent with predictions from paleomagnetic data and carbon cycle modeling.

  15. Diffusion and Settling in Ap/Bp Stars

    SciTech Connect

    Turcotte, S

    2003-04-09

    Ap/Bp stars are magnetic chemically peculiar early A and late B type stars of the main sequence. They exhibit peculiar surface abundance anomalies that are thought to be the result of gravitational settling and radiative levitation. The physics of diffusion in these stars are reviewed briefly and some model predictions are discussed. While models reproduce some observations reasonably well, more work is needed before the behavior of diffusing elements in a complex magnetic field is fully understood.

  16. Predialysis systolic BP variability and outcomes in hemodialysis patients.

    PubMed

    Shafi, Tariq; Sozio, Stephen M; Bandeen-Roche, Karen J; Ephraim, Patti L; Luly, Jason R; St Peter, Wendy L; McDermott, Aidan; Scialla, Julia J; Crews, Deidra C; Tangri, Navdeep; Miskulin, Dana C; Michels, Wieneke M; Jaar, Bernard G; Herzog, Charles A; Zager, Philip G; Meyer, Klemens B; Wu, Albert W; Boulware, L Ebony

    2014-04-01

    BP variability (BPV) is an important predictor of outcomes in the general population, but its association with clinical outcomes in hemodialysis patients is not clear. We identified 11,291 patients starting dialysis in 2003-2008 and followed them through December 31, 2008 (median=22 months). Predialysis systolic BPV was assessed over monthly intervals. Outcomes included factors associated with BPV, mortality (all-cause and cardiovascular), and first cardiovascular event (cardiovascular death or hospitalization). Patients' mean age was 62 years, 55% of patients were men, and 58% of patients were white. Modifiable factors associated with higher BPV included obesity, higher calcium-phosphate product levels, and lower hemoglobin concentration; factors associated with lower BPV included greater fluid removal, achievement of prescribed dry weight during dialysis, higher hemoglobin concentration, and antihypertensive regimens without β-blockers or renin-angiotensin system blocking agents. In total, 3200 deaths occurred, including 1592 cardiovascular deaths. After adjustment for demographics, comorbidities, and clinical factors, higher predialysis BPV was associated with increased risk of all-cause mortality (hazard ratio [HR], 1.18; 95% confidence interval [95% CI] per 1 SD increase in BPV, 1.13 to 1.22), cardiovascular mortality (HR, 1.18; 95% CI, 1.12 to 1.24), and first cardiovascular event (HR, 1.11; 95% CI, 1.07 to 1.15). Results were similar when BPV was categorized in tertiles and patients were stratified by baseline systolic BP. In summary, predialysis systolic BPV is an important, potentially modifiable risk factor for death and cardiovascular outcomes in incident hemodialysis patients. Studies of BP management in dialysis patients should focus on both absolute BP and BPV.

  17. A 70,000 year multiproxy record of climatic and environmental change from Rano Aroi peatland (Easter Island)

    NASA Astrophysics Data System (ADS)

    Margalef, Olga; Cañellas-Boltà, Núria; Pla-Rabes, Sergi; Giralt, Santiago; Pueyo, Juan Jose; Joosten, Hans; Rull, Valentí; Buchaca, Teresa; Hernández, Armand; Valero-Garcés, Blas L.; Moreno, Ana; Sáez, Alberto

    2013-09-01

    The Rano Aroi mire on Easter Island (also known as Rapa Nui; 27°09‧S, 109°27‧W, 430 m above sea level) provides a unique non-marine record in the central South Pacific Ocean for reconstructing Late Pleistocene environmental changes. The results of a multiproxy study on two cores from the center and margin of the Rano Aroi mire, including peat stratigraphy, facies analysis, elemental and isotope geochemistry on bulk organic matter, X-ray fluorescence (XRF) core scanning and macrofossil analysis, were used to infer past water levels and vegetation changes. The chronology was based on 18 14C AMS dates for the upper 8.7 m. The extrapolated age for the base of the sequence is 70 kyr, which implies that this record is the oldest paleolimnological record on Easter Island. The recovered Rano Aroi sequence consists of a radicel peat formed primarily from the remains of sedges, grasses and Polygonaceae that have accumulated since Marine Isotopic Stage (MIS) 4 (70 kyr BP) to the present. From 60 to 40 kyr BP (MIS 3), high precipitation/runoff events were recorded as organic mud facies with lighter δ13C, low C/N values and high Ti content, indicating higher detritic input to the mire. A gradual shift in δ13C bulk organic matter from - 14% to - 26%, recorded between 50 and 45 cal kyr BP, suggests a progressive change in local peat-forming vegetation from C4 to C3 plant types. Post-depositional Ca and Fe enrichment during sub-aerial peat exposure and very low sedimentation rates indicate lower water tables during Late MIS 3 (39-31 cal kyr BP). During MIS 2 (27.8-19 cal kyr BP), peat production rates were very low, most likely due to cold temperatures, as reconstructed from other Easter Island records during the Last Glacial Maximum (LGM). Geochemical and macrofossil evidence shows that peat accumulation reactivates at approximately 17.5 cal kyr BP, reaching the highest accumulation rates at 14 cal kyr BP. Peat accretion decreased from 5.0 to 2.5 cal kyr BP, coinciding

  18. Levels of the E2 interacting protein TopBP1 modulate papillomavirus maintenance stage replication

    SciTech Connect

    Kanginakudru, Sriramana; DeSmet, Marsha; Thomas, Yanique; Morgan, Iain M.; Androphy, Elliot J.

    2015-04-15

    The evolutionarily conserved DNA topoisomerase II beta-binding protein 1 (TopBP1) functions in DNA replication, DNA damage response, and cell survival. We analyzed the role of TopBP1 in human and bovine papillomavirus genome replication. Consistent with prior reports, TopBP1 co-localized in discrete nuclear foci and was in complex with papillomavirus E2 protein. Similar to E2, TopBP1 is recruited to the region of the viral origin of replication during G1/S and early S phase. TopBP1 knockdown increased, while over-expression decreased transient virus replication, without affecting cell cycle. Similarly, using cell lines harboring HPV-16 or HPV-31 genome, TopBP1 knockdown increased while over-expression reduced viral copy number relative to genomic DNA. We propose a model in which TopBP1 serves dual roles in viral replication: it is essential for initiation of replication yet it restricts viral copy number. - Highlights: • Protein interaction study confirmed In-situ interaction between TopBP1 and E2. • TopBP1 present at papillomavirus ori in G1/S and early S phase of cell cycle. • TopBP1 knockdown increased, over-expression reduced virus replication. • TopBP1 protein level change did not influence cell survival or cell cycle. • TopBP1 displaced from papillomavirus ori after initiation of replication.

  19. Heritability of HR and BP Response To Exercise Training in the HERITAGE Family Study.

    ERIC Educational Resources Information Center

    Rice, Treva; Gagnon, Jacques; Leon, Arthur S.; Skinner, James S.; Wilmore, Jack H.; Bouchard, Claude; Rao, D. C.

    2002-01-01

    Assessed the heritability of response to exercise training in resting blood pressure (BP) and heart rate (HR) among sedentary Caucasians comprising 98 families who completed an exercise training program. Results indicated that the trainability of systolic BP and HR in families with elevated BP was partially determined by genetic factors. Diastolic…

  20. Modification over time of pulse wave velocity parallel to changes in aortic BP, as well as in 24-h ambulatory brachial BP.

    PubMed

    Oliveras, A; Segura, J; Suarez, C; García-Ortiz, L; Abad-Cardiel, M; Vigil, L; Gómez-Marcos, M A; Sans Atxer, L; Martell-Claros, N; Ruilope, L M; de la Sierra, A

    2016-03-01

    Arterial stiffness as assessed by carotid-femoral pulse wave velocity (cfPWV) is a marker of preclinical organ damage and a predictor of cardiovascular outcomes, independently of blood pressure (BP). However, limited evidence exists on the association between long-term variation (Δ) on aortic BP (aoBP) and ΔcfPWV. We aimed to evaluate the relationship of ΔBP with ΔcfPWV over time, as assessed by office and 24-h ambulatory peripheral BP, and aoBP. AoBP and cfPWV were evaluated in 209 hypertensive patients with either diabetes or metabolic syndrome by applanation tonometry (Sphygmocor) at baseline(b) and at 12 months of follow-up(fu). Peripheral BP was also determined by using validated oscillometric devices (office(o)-BP) and on an outpatient basis by using a validated (Spacelabs-90207) device (24-h ambulatory BP). ΔcfPWV over time was calculated as follows: ΔcfPWV=[(cfPWVfu-cfPWVb)/cfPWVb] × 100. ΔBP over time resulted from the same formula applied to BP values obtained with the three different measurement techniques. Correlations (Spearman 'Rho') between ΔBP and ΔcfPWV were calculated. Mean age was 62 years, 39% were female and 80% had type 2 diabetes. Baseline office brachial BP (mm Hg) was 143±20/82±12. Follow-up (12 months later) office brachial BP (mm Hg) was 136±20/79±12. ΔcfPWV correlated with ΔoSBP (Rho=0.212; P=0.002), Δ24-h SBP (Rho=0.254; P<0.001), Δdaytime SBP (Rho=0.232; P=0.001), Δnighttime SBP (Rho=0.320; P<0.001) and ΔaoSBP (Rho=0.320; P<0.001). A multiple linear regression analysis included the following independent variables: ΔoSBP, Δ24-h SBP, Δdaytime SBP, Δnighttime SBP and ΔaoSBP. ΔcfPWV was independently associated with Δ24-h SBP (β-coefficient=0.195; P=0.012) and ΔaoSBP (β-coefficient= 0.185; P=0.018). We conclude that changes in both 24-h SBP and aoSBP more accurately reflect changes in arterial stiffness than do office BP measurements.

  1. Protease-sensitive prions with 144-bp insertion mutations

    PubMed Central

    Puoti, Gianfranco; Yuan, Jue; Qing, Liuting; Wang, Heming; Kong, Qingzhong; Gambetti, Pierluigi; Zou, Wen-Quan

    2013-01-01

    Insertion of 144-base pair (bp) containing six extra octapeptide repeats between residues 51 and 91 of prion protein (PrP) gene is associated with inherited prion diseases. Most cases linked to this insertion examined by Western blotting showed detectable proteinase K-resistant PrPSc (rPrPSc) resembling PrPSc type 1 and type 2 in sporadic Creutzfeldt-Jakob disease (sCJD), or PrP7-8 in Gerstmann-Sträussler-Scheinker disease. However, cases lacking detectable rPrPSc also have been reported. Which PrP conformer is associated with neuropathological changes in the cases without detectable rPrPSc remains to be determined. Here we report that while all six but one subjects with the 144-bp insertion mutations examined display the pathognomonic PrP patches in the cerebellum, one of them exhibits no detectable typical rPrPSc even in PrPSc-enriched preparations. Instead, a large amount of abnormal PrP is captured from this case by gene 5 protein and sodium phosphotungstate, reagents that have been proved to specifically capture abnormal PrP. All captured abnormal PrP from the cerebellum and other brain regions is virtually sensitive to PK-digestion (termed sPrPSc). The presence of the predominant sPrPSc but absence of rPrPSc in this 144-bp insertion-linked inherited CJD case suggests that mutant sPrPSc is the main component of the PrP deposit patches and sPrPSc is sufficient to cause neurotoxicity and prion disease. PMID:23515139

  2. Biomechanical parameters of the BP-enriched bone cement.

    PubMed

    Matuszewski, Łukasz; Olchowik, Grażyna; Mazurkiewicz, Tomasz; Kowalczyk, Bartłomiej; Zdrojewska, Agata; Matuszewska, Anna; Ciszewski, Andrzej; Gospodarek, Małgorzata; Morawik, Iwona

    2014-05-01

    Bisphosphonates (BPs) are well-known substances with very efficient antiresorptive properties. Their beneficial actions are useful not only in achieving better bone mineral density but also in improving bone microarchitecture, strength and, consequently, its quality. Surgical cement, being a polymer composite, is required to be highly biocompatible and biotolerant. The goal of the presented study was to assess whether the enrichment of cement with pamidronate has changed its biomechanical properties. We compared the biomechanical parameters of clean bone cement and BP-enriched bone cement, which were both used formerly in our rat models. Biomechanical properties of BP-enriched bone cement are defined by two basic terms: stress and strain, which are caused by the influence of external force. In the investigatory process of the bone's biomechanical parameters, the compressive test and the three-point flexural tests were used. During the three-point flexural investigation, the sample was supported at both ends and loaded in the middle, resulting in a flexure. After a specific range of flexure, the sample was fractured. In obtained results, there were no significant differences in the values of the stress determined at the point of maximal load and the energy stored in the samples for proportional stress-strain limit (elastic region). There were also no significant differences in the density of the samples. The study shows that the enrichment of bisphosphonates causes yielding of the bone cement material. In the presented data, we conclude that use of pamidronate implanted in bone cement did not have a detrimental effect on its biomechanical properties. Therefore, the obtained results encouraged us to perform further in vivo experiments which assess the biomechanical properties of bones implanted with BP-enriched bone cement.

  3. Feasibility study report for the 200-BP-1 operable unit

    SciTech Connect

    Not Available

    1993-06-01

    This feasibility study examines a range of alternatives and provides recommendations for selecting a preferred alternative for remediating contamination at the 200-BP-1 operable unit. The 200-BP-1 operable unit is located in the center of the Hanford Site along the northern boundary of the 200 East Area. The 241-BY Tank Farm is located immediately to the south of the operable unit. 200-BP-1 is a source operable unit with contaminated soils associated primarily with nine inactive cribs (known as the 216-B cribs). These cribs were used for disposal of low-level radioactive liquid waste from U Plant uranium recovery operations, and waste storage tank condensate from the adjacent 241-BY Tank Farm. The cribs used for disposal of U Plant waste were in operation from 1955--1965, and the cribs used for disposal of tank condensate were in operation from 1965--1975. In addition to the cribs, four unplanned releases of radioactive materials have occurred within the operable unit. Contaminated surface soils associated with the unplanned releases have been consolidated over the cribs and covered with clean soil to reduce contaminant migration and exposure. Discharge of wastes to the cribs has resulted in soil and groundwater contamination. The groundwater is being addressed as part of the 200 East Aggregate Area, groundwater operable unit. Contaminated soils at the site can be categorized by the types of contaminants, their distribution in the soil column, and the risk posed by the various potential exposure pathways. Below the clean soil cover, the near surface soils contain low-levels of contamination with cesium-137, radium-226, strontium-90, thorium-228, and uranium. The lifetime incremental cancer risk associated with these soils if they were exposed at the surface is 9{times}10{sup {minus}5}.

  4. Risk assessment of logistics outsourcing based on BP neural network

    NASA Astrophysics Data System (ADS)

    Liu, Xiaofeng; Tian, Zi-you

    The purpose of this article is to evaluate the risk of the enterprises logistics outsourcing. To get this goal, the paper first analysed he main risks existing in the logistics outsourcing, and then set up a risk evaluation index system of the logistics outsourcing; second applied BP neural network into the logistics outsourcing risk evaluation and used MATLAB to the simulation. It proved that the network error is small and has strong practicability. And this method can be used by enterprises to evaluate the risks of logistics outsourcing.

  5. Carbon isotope (δ13C) excursions suggest times of major methane release during the last 14 kyr in Fram Strait, the deep-water gateway to the Arctic

    NASA Astrophysics Data System (ADS)

    Consolaro, C.; Rasmussen, T. L.; Panieri, G.; Mienert, J.; Bünz, S.; Sztybor, K.

    2015-04-01

    We present results from a sediment core collected from a pockmark field on the Vestnesa Ridge (~ 80° N) in the eastern Fram Strait. This is the only deep-water gateway to the Arctic, and one of the northernmost marine gas hydrate provinces in the world. Eight 14C AMS dates reveal a detailed chronology for the last 14 ka BP. The δ 13C record measured on the benthonic foraminiferal species Cassidulina neoteretis shows two distinct intervals with negative values termed carbon isotope excursion (CIE I and CIE II, respectively). The values were as low as -4.37‰ in CIE I, correlating with the Bølling-Allerød interstadials, and as low as -3.41‰ in CIE II, correlating with the early Holocene. In the Bølling-Allerød interstadials, the planktonic foraminifera also show negative values, probably indicating secondary methane-derived authigenic precipitation affecting the foraminiferal shells. After a cleaning procedure designed to remove authigenic carbonate coatings on benthonic foraminiferal tests from this event, the 13C values are still negative (as low as -2.75‰). The CIE I and CIE II occurred during periods of ocean warming, sea-level rise and increased concentrations of methane (CH4) in the atmosphere. CIEs with similar timing have been reported from other areas in the North Atlantic, suggesting a regional event. The trigger mechanisms for such regional events remain to be determined. We speculate that sea-level rise and seabed loading due to high sediment supply in combination with increased seismic activity as a result of rapid deglaciation may have triggered the escape of significant amounts of methane to the seafloor and the water column above.

  6. New c. 270 kyr strike-slip and uplift rates for the southern Alpine Fault and implications for the New Zealand plate boundary

    NASA Astrophysics Data System (ADS)

    Barth, N. C.; Kulhanek, D. K.; Beu, A. G.; Murray-Wallace, C. V.; Hayward, B. W.; Mildenhall, D. C.; Lee, D. E.

    2014-07-01

    Along 100 km of the Alpine Fault, major valleys and glacial deposits can be matched across an 8000 m dextral offset. We use paleontologic and stratigraphic age constraints to date c. 270 ka marine sediments uplifted to 600 m elevation and overlying c. 270 ka glacial deposits related to the 8000 m dextral offset. These constraints yield a fault-proximal Australian plate uplift rate of 2.6 (-0.5/+0.4) mm/yr and an Alpine Fault dextral slip rate of 29.6 (-2.5/+4.5) mm/yr. Our rates resolve an apparent along-strike drop in strike-slip rate and instead support a relatively constant along-strike dextral slip rate of ˜28 mm/yr (˜80% of current Australian-Pacific plate boundary motion). We argue that the rate of dextral slip on the southern Alpine Fault has been relatively constant over the last ≥3.5 myr, and that ductile fault processes may rate-limit the fault from accommodating a progressively higher percentage of plate boundary motion through time (i.e., the fault reached maturity long ago). The spatiotemporally constant strike-slip rate of the southern Alpine Fault and a previously published paleoseismic record of near-regular earthquake recurrence both characterize the Alpine Fault as a mature plate boundary fault zone that behaves in a constant way with behavior predictable over timescales of thousands and hundreds of thousands of years.

  7. 53BP1 mediates productive and mutagenic DNA repair through distinct phosphoprotein interactions.

    PubMed

    Callen, Elsa; Di Virgilio, Michela; Kruhlak, Michael J; Nieto-Soler, Maria; Wong, Nancy; Chen, Hua-Tang; Faryabi, Robert B; Polato, Federica; Santos, Margarida; Starnes, Linda M; Wesemann, Duane R; Lee, Ji-Eun; Tubbs, Anthony; Sleckman, Barry P; Daniel, Jeremy A; Ge, Kai; Alt, Frederick W; Fernandez-Capetillo, Oscar; Nussenzweig, Michel C; Nussenzweig, André

    2013-06-06

    The DNA damage response (DDR) protein 53BP1 protects DNA ends from excessive resection in G1, and thereby favors repair by nonhomologous end-joining (NHEJ) as opposed to homologous recombination (HR). During S phase, BRCA1 antagonizes 53BP1 to promote HR. The pro-NHEJ and antirecombinase functions of 53BP1 are mediated in part by RIF1, the only known factor that requires 53BP1 phosphorylation for its recruitment to double-strand breaks (DSBs). Here, we show that a 53BP1 phosphomutant, 53BP18A, comprising alanine substitutions of the eight most N-terminal S/TQ phosphorylation sites, mimics 53BP1 deficiency by restoring genome stability in BRCA1-deficient cells yet behaves like wild-type 53BP1 with respect to immunoglobulin class switch recombination (CSR). 53BP18A recruits RIF1 but fails to recruit the DDR protein PTIP to DSBs, and disruption of PTIP phenocopies 53BP18A. We conclude that 53BP1 promotes productive CSR and suppresses mutagenic DNA repair through distinct phosphodependent interactions with RIF1 and PTIP.

  8. Development of and assay methodology for antibodies to benzo(a) pyrene (BP)

    SciTech Connect

    Griffin, G.D.; Thomason, R.; Murchison, C.; St. Wecker, P.; Kurka, K.; Ambrose, K.R.

    1986-05-01

    Rabbits, rats and mice have been immunized with BP-bovine serum albumin (BSA) conjugates, administered subcutaneously in Freund's adjuvant. Activity and specificity of antisera preparations from immunized animals was determined by: Double immunodiffusion, passive hemagglutination, enzyme-linked immunosorbent assay (ELISA) and radioimmunoassay (RIA). All techniques could be successfully used to demonstrate the presence of BP antibodies in immune sera. The fist three assays were used only with BP antigen coupled to a protein. If BSA was used, cross-reactivity against BSA was observed, but differences in extent of reactivity toward BP-BSA and BSA were readily apparent. Antisera from highly immune animals showed anti-BP reactivity at 1-10 x 10/sup 6/ dilutions in the ELISA assay, but did not produce positive reactions in the passive hemagglutination assay at >1:256 dilutions. The RIA assay was used with either /sup 14/C-or /sup 3/H-BP, and relied upon an activated charcoal separation step to effectively remove (>98% efficiency) free BP from antibody-bound BP. Using this RIA assay, estimates of amounts of BP antibodies in antisera (0.1-1% of the immunoglobulin fraction) and antibody specificity for BP structural determinants could be made. These antibodies may form the basis for a novel detection system for BP and/or other polycyclic compounds.

  9. A Structure-Adaptive Hybrid RBF-BP Classifier with an Optimized Learning Strategy.

    PubMed

    Wen, Hui; Xie, Weixin; Pei, Jihong

    2016-01-01

    This paper presents a structure-adaptive hybrid RBF-BP (SAHRBF-BP) classifier with an optimized learning strategy. SAHRBF-BP is composed of a structure-adaptive RBF network and a BP network of cascade, where the number of RBF hidden nodes is adjusted adaptively according to the distribution of sample space, the adaptive RBF network is used for nonlinear kernel mapping and the BP network is used for nonlinear classification. The optimized learning strategy is as follows: firstly, a potential function is introduced into training sample space to adaptively determine the number of initial RBF hidden nodes and node parameters, and a form of heterogeneous samples repulsive force is designed to further optimize each generated RBF hidden node parameters, the optimized structure-adaptive RBF network is used for adaptively nonlinear mapping the sample space; then, according to the number of adaptively generated RBF hidden nodes, the number of subsequent BP input nodes can be determined, and the overall SAHRBF-BP classifier is built up; finally, different training sample sets are used to train the BP network parameters in SAHRBF-BP. Compared with other algorithms applied to different data sets, experiments show the superiority of SAHRBF-BP. Especially on most low dimensional and large number of data sets, the classification performance of SAHRBF-BP outperforms other training SLFNs algorithms.

  10. AMP-activated protein kinase phosphorylates CtBP1 and down-regulates its activity

    SciTech Connect

    Kim, Jae-Hwan; Choi, Soo-Youn; Kang, Byung-Hee; Lee, Soon-Min; Cho, Eun-Jung; Youn, Hong-Duk

    2013-02-01

    Highlights: ► AMPK phosphorylates CtBP1 on serine 158. ► AMPK-mediated phosphorylation of CtBP1 causes the ubiquitination and nuclear export of CtBP1. ► AMPK downregulates the CtBP1-mediated repression of Bax transcription. -- Abstract: CtBP is a transcriptional repressor which plays a significant role in the regulation of cell proliferation and tumor progression. It was reported that glucose withdrawal causes induction of Bax due to the dissociation of CtBP from the Bax promoter. However, the precise mechanism involved in the regulation of CtBP still remains unclear. In this study, we found that an activated AMP-activated protein kinase (AMPK) phosphorylates CtBP1 on Ser-158 upon metabolic stresses. Moreover, AMPK-mediated phosphorylation of CtBP1 (S158) attenuates the repressive function of CtBP1. We also confirmed that triggering activation of AMPK by various factors resulted in an increase of Bax gene expression. These findings provide connections of AMPK with CtBP1-mediated regulation of Bax expression for cell death under metabolic stresses.

  11. A Structure-Adaptive Hybrid RBF-BP Classifier with an Optimized Learning Strategy

    PubMed Central

    Wen, Hui; Xie, Weixin; Pei, Jihong

    2016-01-01

    This paper presents a structure-adaptive hybrid RBF-BP (SAHRBF-BP) classifier with an optimized learning strategy. SAHRBF-BP is composed of a structure-adaptive RBF network and a BP network of cascade, where the number of RBF hidden nodes is adjusted adaptively according to the distribution of sample space, the adaptive RBF network is used for nonlinear kernel mapping and the BP network is used for nonlinear classification. The optimized learning strategy is as follows: firstly, a potential function is introduced into training sample space to adaptively determine the number of initial RBF hidden nodes and node parameters, and a form of heterogeneous samples repulsive force is designed to further optimize each generated RBF hidden node parameters, the optimized structure-adaptive RBF network is used for adaptively nonlinear mapping the sample space; then, according to the number of adaptively generated RBF hidden nodes, the number of subsequent BP input nodes can be determined, and the overall SAHRBF-BP classifier is built up; finally, different training sample sets are used to train the BP network parameters in SAHRBF-BP. Compared with other algorithms applied to different data sets, experiments show the superiority of SAHRBF-BP. Especially on most low dimensional and large number of data sets, the classification performance of SAHRBF-BP outperforms other training SLFNs algorithms. PMID:27792737

  12. SPECTROPOLARIMETRY OF THE CLASSICAL T TAURI STAR BP TAU

    SciTech Connect

    Chen, Wei; Johns-Krull, Christopher M. E-mail: cmj@rice.edu

    2013-10-20

    We implement a least-squares deconvolution (LSD) code to study magnetic fields on cool stars. We first apply our code to high-resolution optical echelle spectra of 53 Cam (a magnetic Ap star) and three well-studied cool stars (Arcturus, 61 Cyg A, and ξ Boo A) as well as the Sun (by observing the asteroid Vesta) as tests of the code and the instrumentation. Our analysis is based on several hundred photospheric lines spanning the wavelength range 5000 Å to 9000 Å. We then apply our LSD code to six nights of data on the Classical T Tauri Star BP Tau. A maximum longitudinal field of 370 ± 80 G is detected from the photospheric lines on BP Tau. A 1.8 kG dipole tilted at 129° with respect to the rotation axis and a 1.4 kG octupole tilted at 104° with respect to the rotation axis, both with a filling factor of 0.25, best fit our LSD Stokes V profiles. Measurements of several emission lines (He I 5876 Å, Ca II 8498 Å, and 8542 Å) show the presence of strong magnetic fields in the line formation regions of these lines, which are believed to be the base of the accretion footpoints. The field strength measured from these lines shows night-to-night variability consistent with rotation of the star.

  13. Spectropolarimetry of the Classical T Tauri Star BP Tau

    NASA Astrophysics Data System (ADS)

    Chen, Wei; Johns-Krull, Christopher M.

    2013-10-01

    We implement a least-squares deconvolution (LSD) code to study magnetic fields on cool stars. We first apply our code to high-resolution optical echelle spectra of 53 Cam (a magnetic Ap star) and three well-studied cool stars (Arcturus, 61 Cyg A, and ξ Boo A) as well as the Sun (by observing the asteroid Vesta) as tests of the code and the instrumentation. Our analysis is based on several hundred photospheric lines spanning the wavelength range 5000 Å to 9000 Å. We then apply our LSD code to six nights of data on the Classical T Tauri Star BP Tau. A maximum longitudinal field of 370 ± 80 G is detected from the photospheric lines on BP Tau. A 1.8 kG dipole tilted at 129° with respect to the rotation axis and a 1.4 kG octupole tilted at 104° with respect to the rotation axis, both with a filling factor of 0.25, best fit our LSD Stokes V profiles. Measurements of several emission lines (He I 5876 Å, Ca II 8498 Å, and 8542 Å) show the presence of strong magnetic fields in the line formation regions of these lines, which are believed to be the base of the accretion footpoints. The field strength measured from these lines shows night-to-night variability consistent with rotation of the star.

  14. Research on PGNAA adaptive analysis method with BP neural network

    NASA Astrophysics Data System (ADS)

    Peng, Ke-Xin; Yang, Jian-Bo; Tuo, Xian-Guo; Du, Hua; Zhang, Rui-Xue

    2016-11-01

    A new approach method to dealing with the puzzle of spectral analysis in prompt gamma neutron activation analysis (PGNAA) is developed and demonstrated. It consists of utilizing BP neural network to PGNAA energy spectrum analysis which is based on Monte Carlo (MC) simulation, the main tasks which we will accomplish as follows: (1) Completing the MC simulation of PGNAA spectrum library, we respectively set mass fractions of element Si, Ca, Fe from 0.00 to 0.45 with a step of 0.05 and each sample is simulated using MCNP. (2) Establishing the BP model of adaptive quantitative analysis of PGNAA energy spectrum, we calculate peak areas of eight characteristic gamma rays that respectively correspond to eight elements in each individual of 1000 samples and that of the standard sample. (3) Verifying the viability of quantitative analysis of the adaptive algorithm where 68 samples were used successively. Results show that the precision when using neural network to calculate the content of each element is significantly higher than the MCLLS.

  15. RREL TREATABILITY DATABASE - VERSION 5.0

    EPA Science Inventory

    There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field. This database can be obtained by contacting Tom Holdsworth, U.S. EPA, 26 West Martin Luther King D...

  16. Recurrent 15q11.2 BP1-BP2 microdeletions and microduplications in the etiology of neurodevelopmental disorders.

    PubMed

    Picinelli, Chiara; Lintas, Carla; Piras, Ignazio Stefano; Gabriele, Stefano; Sacco, Roberto; Brogna, Claudia; Persico, Antonio Maria

    2016-12-01

    Rare and common CNVs can contribute to the etiology of neurodevelopmental disorders. One of the recurrent genomic aberrations associated with these phenotypes and proposed as a susceptibility locus is the 15q11.2 BP1-BP2 CNV encompassing TUBGCP5, CYFIP1, NIPA2, and NIPA1. Characterizing by array-CGH a cohort of 243 families with various neurodevelopmental disorders, we identified five patients carrying the 15q11.2 duplication and one carrying the deletion. All CNVs were confirmed by qPCR and were inherited, except for one duplication where parents were not available. The phenotypic spectrum of CNV carriers was broad but mainly neurodevelopmental, in line with all four genes being implicated in axonal growth and neural connectivity. Phenotypically normal and mildly affected carriers complicate the interpretation of this aberration. This variability may be due to reduced penetrance or altered gene dosage on a particular genetic background. We evaluated the expression levels of the four genes in peripheral blood RNA and found the expected reduction in the deleted case, while duplicated carriers displayed high interindividual variability. These data suggest that differential expression of these genes could partially account for differences in clinical phenotypes, especially among duplication carriers. Furthermore, urinary Mg(2+) levels appear negatively correlated with NIPA2 gene copy number, suggesting they could potentially represent a useful biomarker, whose reliability will need replication in larger samples. © 2016 Wiley Periodicals, Inc.

  17. An Analysis of the Rapidly Rotating Bp star HD 133880

    NASA Technical Reports Server (NTRS)

    Bailey, J. D.; Grunhut, J.; Shultz, M.; Wade, G.; Landstreet, J. D.; Bohlender, D.; Lim, J.; Wong, K.; Drake, S.; Linsky, J.

    2012-01-01

    HD 133880 is a rapidly rotating chemically peculiar B-type (Bp) star (nu sin i approx = 103km/s) and is host to one of the strongest magnetic fields of any Ap/Bp star. A member of the Upper Centaurus Lupus association, it is a star with a well-determined age of 16 Myr. 12 new spectra, four of which are polarimetric, obtained from the FEROS, ESPaDOnS and HARPS instruments, provide sufficient material from which to re-evaluate the magnetic field and obtain a first approximation to the atmospheric abundance distributions of He, O, Mg, Si, Ti. Cr, Fe, Ni, Pr and Nd. An abundance analysis was carried out using ZEEMAN, a program which synthesizes spectral line profiles for stars with permeating magnetic fields. The magnetic field structure was characterized by a colinear multipole expansion from the observed variations of the longitudinal and surface fields with rotational phase. Both magnetic hemispheres are clearly visible during the stellar rotation, and thus a three-ring abundance distribution model encompassing both magnetic poles and magnetic equator with equal spans in colatitude was adopted. Using the new magnetic field measurements and optical photometry together with previously published data, we refine the period of HD 133880 to P = 0.877 476 +/- 0.000009 d. Our simple axisymmetric magnetic field model is based on a predominantly quadrupolar component that roughly describes the field variations. Using spectrum synthesis, we derived mean abundances for O, Mg, Si, Ti, Cr, Fe and Pr. All elements; except Mg, are overabundant compared to the Son. Mg appears to be approximately uniform over the stellar surface, while all other elements are more abundant in the negative magnetic hemisphere than in the positive magnetic hemisphere. In contrast to most Ap/Bp stars which show an underabundance in 0, in HD 133880 this element is clearly overabundant compared to the solar abundance ratio. In studying the Ha and Paschen lines in the optical spectra, we could not

  18. BRCA1 Directs the Repair Pathway to Homologous Recombination by Promoting 53BP1 Dephosphorylation.

    PubMed

    Isono, Mayu; Niimi, Atsuko; Oike, Takahiro; Hagiwara, Yoshihiko; Sato, Hiro; Sekine, Ryota; Yoshida, Yukari; Isobe, Shin-Ya; Obuse, Chikashi; Nishi, Ryotaro; Petricci, Elena; Nakada, Shinichiro; Nakano, Takashi; Shibata, Atsushi

    2017-01-10

    BRCA1 promotes homologous recombination (HR) by activating DNA-end resection. By contrast, 53BP1 forms a barrier that inhibits DNA-end resection. Here, we show that BRCA1 promotes DNA-end resection by relieving the 53BP1-dependent barrier. We show that 53BP1 is phosphorylated by ATM in S/G2 phase, promoting RIF1 recruitment, which inhibits resection. 53BP1 is promptly dephosphorylated and RIF1 released, despite remaining unrepaired DNA double-strand breaks (DSBs). When resection is impaired by CtIP/MRE11 endonuclease inhibition, 53BP1 phosphorylation and RIF1 are sustained due to ongoing ATM signaling. BRCA1 depletion also sustains 53BP1 phosphorylation and RIF1 recruitment. We identify the phosphatase PP4C as having a major role in 53BP1 dephosphorylation and RIF1 release. BRCA1 or PP4C depletion impairs 53BP1 repositioning, EXO1 recruitment, and HR progression. 53BP1 or RIF1 depletion restores resection, RAD51 loading, and HR in PP4C-depleted cells. Our findings suggest that BRCA1 promotes PP4C-dependent 53BP1 dephosphorylation and RIF1 release, directing repair toward HR.

  19. Role of the Bp35 cell surface polypeptide in human B-cell activation.

    PubMed Central

    Clark, E A; Shu, G; Ledbetter, J A

    1985-01-01

    A 35-kDa polypeptide, Bp35, expressed on the surface of all B cells, plays a role in B-cell activation. Monoclonal antibodies to Bp35 stimulate human tonsillar B cells to proliferate. The activation induced by anti-Bp35 is similar to anti-Ig-mediated in several ways: the activation does not require T cells but is augmented by T-cell-derived allogeneic factors; monovalent Fab fragments to Bp35 do not trigger proliferation but instead block activation by whole antibody, indicating that cross-linking is required; and induction by anti-Bp35, like the induction by anti-Ig, is inhibited by monoclonal anti-IgM via an Fc domain-dependent mechanism. However, several features of anti-Bp35-mediated proliferation are clearly different from activation by anti-Ig: anti-Bp35 monoclonal antibodies do not require attachment to beads to function, the proliferation induced by anti-Bp35 and anti-Ig is additive, and Fab fragments of anti-Bp35 augment proliferation induced by anti-Ig. Models for the possible function of the Bp35 polypeptide as either a "bridge" or a "second signal" with surface Ig in B-cell activation are discussed. PMID:3872456

  20. Identify Melatonin as a Novel Therapeutic Reagent in the Treatment of 1-Bromopropane(1-BP) Intoxication

    PubMed Central

    Xu, Yongpeng; Wang, Shuo; Jiang, Lulu; Wang, Hui; Yang, Yilin; Li, Ming; Wang, Xujing; Zhao, Xiulan; Xie, Keqin

    2016-01-01

    Abstract 1-Bromopropane (1-BP) has been used as an alternative for fluoride compounds and 1-BP intoxication may involve lung, liver, and central neural system (CNS). Our previous studies showed that 1-BP impaired memory ability by compromising antioxidant cellular defenses. Melatonin is a powerful endogenous antioxidant, and the objective of this study was to explore the therapeutic role of melatonin in the treatment of 1-BP intoxication. Rats were intragastrically treated with 1-BP with or without melatonin, and then sacrificed on 27th day after 1-BP administration. The Morris water maze (MWM) test was used to evaluate the spatial learning and memory ability of the experimental animals, and NeuN staining was performed to assess neuron loss in hippocampus. We found that rats treated with 1-BP spent more time and swam longer distance before landing on the hidden platform with a comparable swimming speed, which was markedly mitigated by the pretreatment with melatonin in a concentration-dependent manner. In addition, 1-BP-induced notable decrease in neuron population in hippocampus by promoting apoptosis, and melatonin pretreatment attenuated those changes in brain. The GSH/GSSG ratio was proportionately decreased and heme oxygenase 1 was increased in the rats exposed to 1-BP (Figure 6), and administration of melatonin restored them. Meanwhile, MDA, the level of lipid peroxidation product, was significantly increased upon exposed to 1-BP, which was significantly attenuated by melatonin pretreatment, indicating that administration of 1-BP could interfere with redox homeostasis of brain in rat, and such 1-BP-induced biomedical changes were reversed by treatment with melatonin. We conclude that treatment with melatonin attenuates 1-BP-induced CNS toxicity through its ROS scavenging effect. PMID:26817862

  1. Identify Melatonin as a Novel Therapeutic Reagent in the Treatment of 1-Bromopropane(1-BP) Intoxication.

    PubMed

    Xu, Yongpeng; Wang, Shuo; Jiang, Lulu; Wang, Hui; Yang, Yilin; Li, Ming; Wang, Xujing; Zhao, Xiulan; Xie, Keqin

    2016-01-01

    1-Bromopropane (1-BP) has been used as an alternative for fluoride compounds and 1-BP intoxication may involve lung, liver, and central neural system (CNS). Our previous studies showed that 1-BP impaired memory ability by compromising antioxidant cellular defenses. Melatonin is a powerful endogenousantioxidant, and the objective of this study was to explore the therapeutic role of melatonin in the treatment of 1-BP intoxication. Rats were intragastrically treated with 1-BP with or without melatonin, and then sacrificed on 27th day after 1-BP administration. The Morris water maze (MWM) test was used to evaluate the spatial learning and memory ability of the experimental animals, and NeuN staining was performed to assess neuron loss in hippocampus. We found that rats treated with 1-BP spent more time and swam longer distance before landing on the hidden platform with a comparable swimming speed, which was markedly mitigated by the pretreatment with melatonin in a concentration-dependent manner. In addition, 1-BP-induced notable decrease in neuron population in hippocampus by promoting apoptosis, and melatonin pretreatment attenuated those changes in brain. The GSH/GSSG ratio was proportionately decreased and heme oxygenase 1 was increased in the rats exposed to 1-BP (Figure 6), and administration of melatonin restored them. Meanwhile, MDA, the level of lipid peroxidation product, was significantly increased upon exposed to 1-BP, which was significantly attenuated by melatonin pretreatment, indicating that administration of 1-BP could interfere with redox homeostasis of brain in rat, and such 1-BP-induced biomedical changes were reversed by treatment with melatonin.We conclude that treatment with melatonin attenuates 1-BP-induced CNS toxicity through its ROS scavenging effect.

  2. The Translational Repressor 4E-BP1 Contributes to Diabetes-Induced Visual Dysfunction

    PubMed Central

    Miller, William P.; Mihailescu, Maria L.; Yang, Chen; Barber, Alistair J.; Kimball, Scot R.; Jefferson, Leonard S.; Dennis, Michael D.

    2016-01-01

    Purpose The translational repressor 4E-BP1 interacts with the mRNA cap-binding protein eIF4E and thereby promotes cap-independent translation of mRNAs encoding proteins that contribute to diabetic retinopathy. Interaction of 4E-BP1 with eIF4E is enhanced in the retina of diabetic rodents, at least in part, as a result of elevated 4E-BP1 protein expression. In the present study, we examined the role of 4E-BP1 in diabetes-induced visual dysfunction, as well as the mechanism whereby hyperglycemia promotes 4E-BP1 expression. Methods Nondiabetic and diabetic wild-type and 4E-BP1/2 knockout mice were evaluated for visual function using a virtual optomotor test (Optomotry). Retinas were harvested from nondiabetic and type 1 diabetic mice and analyzed for protein abundance and posttranslational modifications. Similar analyses were performed on cells in culture exposed to hyperglycemic conditions or an O-GlcNAcase inhibitor (Thiamet G [TMG]). Results Diabetes-induced visual dysfunction was delayed in mice deficient of 4E-BP1/2 as compared to controls. 4E-BP1 protein expression was enhanced by hyperglycemia in the retina of diabetic rodents and by hyperglycemic conditions in retinal cells in culture. A similar elevation in 4E-BP1 expression was observed with TMG. The rate of 4E-BP1 degradation was significantly prolonged by either hyperglycemic conditions or TMG. A PEST motif in the C-terminus of 4E-BP1 regulated polyubiquitination, turnover, and binding of an E3 ubiquitin ligase complex containing CUL3. Conclusions The findings support a model whereby elevated 4E-BP1 expression observed in the retina of diabetic rodents is the result of O-GlcNAcylation of 4E-BP1 within its PEST motif. PMID:26998719

  3. The determination of potential energy curve and dipole moment of the (5)0{sup +} electronic state of {sup 85}Rb{sup 133}Cs molecule by high resolution photoassociation spectroscopy

    SciTech Connect

    Yuan, Jinpeng; Zhao, Yanting Ji, Zhonghua; Li, Zhonghao; Xiao, Liantuan; Jia, Suotang; Kim, Jin-Tae

    2015-12-14

    We present the formation of ultracold {sup 85}Rb{sup 133}Cs molecules in the (5)0{sup +} electronic state by photoassociation and their detection via resonance-enhanced two-photon ionization. Up to v = 47 vibrational levels including the lowest v = 0 vibrational and lowest J = 0 levels are identified with rotationally resolved high resolution photoassociation spectra. Precise Dunham coefficients are determined for the (5)0{sup +} state with high accuracy, then the Rydberg-Klein-Rees potential energy curve is derived. The electric dipole moments with respect to the vibrational numbers of the (5)0{sup +} electronic state of {sup 85}Rb{sup 133}Cs molecule are also measured in the range between 1.9 and 4.8 D. These comprehensive studies on previously unobserved rovibrational levels of the (5)0{sup +} state are helpful to understand the molecular structure and discover suitable transition pathways for transferring ultracold atoms to deeply bound rovibrational levels of the electronic ground state.

  4. Characterization of the Particulate Emissions from the BP ...

    EPA Pesticide Factsheets

    Opportunistic particle samples were gathered from the sail of a tethered aerostat during at-sea plume sampling of the purposely-burned surface oil during the BP Deepwater Horizon disaster in the Gulf of Mexico. Particles were analyzed for polycyclic aromatic hydrocarbons (PAHs), organic carbon (OC), elemental carbon (EC), metals, and polychlorinated dibenzodioxins/dibenzofurans (PCDDs/PCDFs). Emission factors were calculated using previous sampling values of background-adjusted CO2 and particulate matter (PM)-bound C. The mean of five thermal-optical analyses indicated that the burned crude oil particulate matter was 93% carbon (w/w) with the predominance being refractory elemental carbon (82% w/w) on average. PAHs accounted for roughly 60 ug/g of the PM mass or 4.5 mg/kg oil burned, at least an order of magnitude less than earlier laboratory based studies. Microscopy indicates that the soot from the in situ oil burns is distinct from more common soot by its aggregate size, primary particle size, and nanostructure within the primary particles. The PCDD/PCDF concentration of the PM was 1.5 to 3.3 ng toxic equivalency (TEQ)/kg PM sampled, about 10-fold lower than from a previous dedicated gas/solid sample, indicating loss of small particle-bound and more volatile PCDD/PCDF congeners through the aerostat sail. This work presents an analysis of smoke particles opportunistically caught during the in situ surface oil burns during the 2010 BP Deepwater Horizon di

  5. Preparation of (5.0%)Er(3+):Y3Al5O12/Pt-(TiO2-Ta2O5) nanocatalysts and application in sonocatalytic decomposition of ametryn in aqueous solution.

    PubMed

    Li, Guanshu; Zhang, Hongbo; Wei, Chunsheng; Huang, Yingying; Dou, Xuekai; Wang, Yidi; Wang, Jun; Song, Youtao

    2017-01-01

    (5.0%)Er(3+):Y3Al5O12/Pt-(TiO2-Ta2O5) powder, as a high effective sonocatalyst, was prepared using sol-gel and calcination method. Then it was characterized by X-ray diffractometer (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDX). In order to evaluate the sonocatalytic activity of the prepared (5.0%)Er(3+):Y3Al5O12/Pt-(TiO2-Ta2O5) powder, the sonocatalytic decomposition of ametryn was studied. In addition, some influencing factors such as different Ti/Ta molar ratios on the sonocatalytic activity of the prepared (5.0%)Er(3+):Y3Al5O12/Pt-(TiO2-Ta2O5) powder, catalyst added amount with ultrasonic irradiation time and used times on the sonocatalytic decomposition efficiency were examined by using ion chromatogram determination. The experimental results showed that the best sonocatalytic decomposition ratio of ametryn were 77.50% based on the N atom calculation and 95.00% based on the S atom calculation, respectively, when the conditions of 10.00mg/L initial concentration, 1.00g/L prepared (5.0%)Er(3+):Y3Al5O12/Pt-(TiO2-Ta2O5) powder (Ti/Ta=1.00:0.25 heat-treated at 550°C for 3.0h) added amount, 150min ultrasonic irradiation (40kHz frequency and 300W output power), 100mL total volume and 25-28°C temperature were adopted. Therefore, the (5.0%)Er(3+):Y3Al5O12/Pt-(TiO2-Ta2O5) composite nanoparticles could be considered as an effective sonocatalyst for decomposition of ametryn in aqueous solution.

  6. In vitro short-term exposure to air pollution PM2.5-0.3 induced cell cycle alterations and genetic instability in a human lung cell coculture model.

    PubMed

    Abbas, Imane; Verdin, Anthony; Escande, Fabienne; Saint-Georges, Françoise; Cazier, Fabrice; Mulliez, Philippe; Courcot, Dominique; Shirali, Pirouz; Gosset, Pierre; Garçon, Guillaume

    2016-05-01

    Although its adverse health effects of air pollution particulate matter (PM2.5) are well-documented and often related to oxidative stress and pro-inflammatory response, recent evidence support the role of the remodeling of the airway epithelium involving the regulation of cell death processes. Hence, the overarching goals of the present study were to use an in vitro coculture model, based on human AM and L132 cells to study the possible alteration of TP53-RB gene signaling pathways (i.e. cell cycle phases, gene expression of TP53, BCL2, BAX, P21, CCND1, and RB, and protein concentrations of their active forms), and genetic instability (i.e. LOH and/or MSI) in the PM2.5-0.3-exposed coculture model. PM2.5-0.3 exposure of human AM from the coculture model induced marked cell cycle alterations after 24h, as shown by increased numbers of L132 cells in subG1 and S+G2 cell cycle phases, indicating apoptosis and proliferation. Accordingly, activation of the TP53-RB gene signaling pathways after the coculture model exposure to PM2.5-0.3 was reported in the L132 cells. Exposure of human AM from the coculture model to PM2.5-0.3 resulted in MS alterations in 3p chromosome multiple critical regions in L132 cell population. Hence, in vitro short-term exposure of the coculture model to PM2.5-0.3 induced cell cycle alterations relying on the sequential occurrence of molecular abnormalities from TP53-RB gene signaling pathway activation and genetic instability.

  7. eIF4E/4E-BP dissociation and 4E-BP degradation in the first mitotic division of the sea urchin embryo.

    PubMed

    Salaün, Patrick; Pyronnet, Stéphane; Morales, Julia; Mulner-Lorillon, Odile; Bellé, Robert; Sonenberg, Nahum; Cormier, Patrick

    2003-03-15

    The mRNA's cap-binding protein eukaryotic translation initiation factor (eIF)4E is a major target for the regulation of translation initiation. eIF4E activity is controlled by a family of translation inhibitors, the eIF4E-binding proteins (4E-BPs). We have previously shown that a rapid dissociation of 4E-BP from eIF4E is related with the dramatic rise in protein synthesis that occurs following sea urchin fertilization. Here, we demonstrate that 4E-BP is destroyed shortly following fertilization and that 4E-BP degradation is sensitive to rapamycin, suggesting that proteolysis could be a novel means of regulating 4E-BP function. We also show that eIF4E/4E-BP dissociation following fertilization is sensitive to rapamycin. Furthermore, while rapamycin modestly affects global translation rates, the drug strongly inhibits cyclin B de novo synthesis and, consequently, precludes the completion of the first mitotic cleavage. These results demonstrate that, following sea urchin fertilization, cyclin B translation, and thus the onset of mitosis, are regulated by a rapamycin-sensitive pathway. These processes are effected at least in part through eIF4E/4E-BP complex dissociation and 4E-BP degradation.

  8. Lamin A/C-dependent interaction with 53BP1 promotes cellular responses to DNA damage

    PubMed Central

    Gibbs-Seymour, Ian; Markiewicz, Ewa; Bekker-Jensen, Simon; Mailand, Niels; Hutchison, Christopher J

    2015-01-01

    Lamins A/C have been implicated in DNA damage response pathways. We show that the DNA repair protein 53BP1 is a lamin A/C binding protein. In undamaged human dermal fibroblasts (HDF), 53BP1 is a nucleoskeleton protein. 53BP1 binds to lamins A/C via its Tudor domain, and this is abrogated by DNA damage. Lamins A/C regulate 53BP1 levels and consequently lamin A/C-null HDF display a 53BP1 null-like phenotype. Our data favour a model in which lamins A/C maintain a nucleoplasmic pool of 53BP1 in order to facilitate its rapid recruitment to sites of DNA damage and could explain why an absence of lamin A/C accelerates aging. PMID:25645366

  9. Weathered Oil and Tar Sampling Data for BP Spill/Deepwater Horizon

    EPA Pesticide Factsheets

    The Deepwater Horizon oil spill (also referred to as the BP oil spill) began on 20 April 2010 in the Gulf of Mexico on the BP-operated Macondo Prospect. Following the explosion and sinking of the Deepwater Horizon oil rig, a sea-floor oil gusher flowed for 87 days, until it was capped on 15 July 2010.In response to the BP oil spill, EPA sampled air, water, sediment, and waste generated by the cleanup operations.

  10. Relationship between CacyBP/SIP expression and prognosis in astrocytoma.

    PubMed

    Zhao, Wei; Wang, Chunlin; Wang, Junyu; Ge, Aiqing; Li, Yiming; Li, Weiqing; Lu, Yicheng

    2011-09-01

    The aim of this study was to investigate the expression of calcyclin-binding protein (also known as Siah-1-interacting protein [CacyBP/SIP]) in astrocytoma and to determine its prognostic value in overall survival of patients with glioblastoma multiforme (GBM). Tissue specimens were obtained from 77 Chinese patients who had undergone surgery for astrocytoma. The expression of CacyBP/SIP was examined by immunohistochemistry. The relationship between CacyBP/SIP and proliferating cell nuclear antigen index (PCNA) expression was investigated, and the prognostic value of CacyBP/SIP expression in patients with astrocytomas was analyzed. Of 77 tumors, 49 (63.6%) were negative for CacyBP/SIP expression. Loss of CacyBP/SIP expression was significantly associated with a high histological grade and with poor survival in univariate and multivariate analyses. Cox multivariable analysis showed that loss of CacyBP/SIP expression correlated with poor prognosis in patients with astrocytomas and was an independent prognostic factor (p<0.05). The mean survival time of patients with tumors that had lost expression of CacyBP/SIP was 25.58months (95% confidence interval [CI], 15.36-25.81months), compared to a mean survival time of 36.37months (95% CI, 27.90-44.84months) for patients with CacyBP/SIP-expressing tumors. CacyBP/SIP expression was also negatively correlated with PCNA expression in astrocytoma tissue (p<0.05). Our findings suggest that CacyBP/SIP may have an important role as a negative regulator of astrocytoma development and progression, and that CacyBP/SIP might be a useful molecular marker for predicting the prognosis of astrocytoma.

  11. Interactions of the human MCM-BP protein with MCM complex components and Dbf4.

    PubMed

    Nguyen, Tin; Jagannathan, Madhav; Shire, Kathy; Frappier, Lori

    2012-01-01

    MCM-BP was discovered as a protein that co-purified from human cells with MCM proteins 3 through 7; results which were recapitulated in frogs, yeast and plants. Evidence in all of these organisms supports an important role for MCM-BP in DNA replication, including contributions to MCM complex unloading. However the mechanisms by which MCM-BP functions and associates with MCM complexes are not well understood. Here we show that human MCM-BP is capable of interacting with individual MCM proteins 2 through 7 when co-expressed in insect cells and can greatly increase the recovery of some recombinant MCM proteins. Glycerol gradient sedimentation analysis indicated that MCM-BP interacts most strongly with MCM4 and MCM7. Similar gradient analyses of human cell lysates showed that only a small amount of MCM-BP overlapped with the migration of MCM complexes and that MCM complexes were disrupted by exogenous MCM-BP. In addition, large complexes containing MCM-BP and MCM proteins were detected at mid to late S phase, suggesting that the formation of specific MCM-BP complexes is cell cycle regulated. We also identified an interaction between MCM-BP and the Dbf4 regulatory component of the DDK kinase in both yeast 2-hybrid and insect cell co-expression assays, and this interaction was verified by co-immunoprecipitation of endogenous proteins from human cells. In vitro kinase assays showed that MCM-BP was not a substrate for DDK but could inhibit DDK phosphorylation of MCM4,6,7 within MCM4,6,7 or MCM2-7 complexes, with little effect on DDK phosphorylation of MCM2. Since DDK is known to activate DNA replication through phosphorylation of these MCM proteins, our results suggest that MCM-BP may affect DNA replication in part by regulating MCM phosphorylation by DDK.

  12. Change in the Nd isotopic composition of the bottom water and detrital sediments on the Bering Slope over the last 500 kyrs with implications for the formation of the North Pacific Intermediate Water

    NASA Astrophysics Data System (ADS)

    Jang, K.; Huh, Y.; Han, Y.

    2015-12-01

    The Bering Sea is a potential location for the formation of the North Pacific Intermediate/Deep Water (NPIW/NPDW) and may play an important role in the global heat distribution. We reconstructed the neodymium isotopic ratio (ɛNd) of authigenic Fe-Mn oxide coatings and detrital sediments on the Bering Slope (IODP Expedition 323 site U1345; water depth 1008 m) over the last 500 kyrs. The ɛNd is a quasi-conservative water mass tracer. We compared three different leaching techniques to assure that authigenic signals are captured without contamination from terrigenous sources: (1) leaching (3 hours) with 0.02 M hydroxylamine hydrochloride (HH) in 25% buffered acetic acid after decarbonation; sediment/solution (v/v) > 10, (2) leaching (1 hour) with 0.02 M HH in 25% buffered acetic acid without decarbonation; sediment/solution ~ 1, and (3) leaching (1 hour) with 0.005 M HH in 1.5% buffered acetic acid-0.003 M Na-EDTA without decarbonation; sediment/solution > 40. The low Al concentrations and less radiogenic ɛNdvalues indicated that method (2) is the most appropriate leaching process. The average ɛNd of the authigenic fraction over the last 500 kyrs is -3.3 ± 0.9 (1σ, n=38), with large temporal fluctuations. The ɛNd of authigenic and detrital fractions are well correlated (r2 ~ 0.66), suggesting that the bottom water composition in the Bering Sea was governed by terrigenous inflow from surrounding areas. Radiogenic ɛNd peaks (up to -1.9) seem to be influenced by radiogenic water inflow from the the Kamchatka or Aluetian arcs. The high bulk density and low b* values imply higher terrigenous versus biological contribution and enhanced sea ice formation. Subsequent brine formation would have triggered sinking of radiogenic surface water, forming the NPIW. On the other hand, non-radiogenic ɛNd troughs (down to -5.3) are observed at times of low bulk density and high b* values. We presume higher biological productivity which is supported by the high opal content at

  13. TopBP1 associates with NBS1 and is involved in homologous recombination repair

    SciTech Connect

    Morishima, Ken-ichi; Sakamoto, Shuichi; Kobayashi, Junya; Izumi, Hideki; Suda, Tetsuji; Matsumoto, Yoshiyuki; Tauchi, Hiroshi; Ide, Hiroshi; Komatsu, Kenshi; Matsuura, Shinya

    2007-11-03

    TopBP1 is involved in DNA replication and DNA damage checkpoint. Recent studies have demonstrated that TopBP1 is a direct positive effecter of ATR. However, it is not known how TopBP1 recognizes damaged DNA. Here, we show that TopBP1 formed nuclear foci after exposure to ionizing radiation, but such TopBP1 foci were abolished in Nijmegen breakage syndrome cells. We also show that TopBP1 physically associated with NBS1 in vivo. These results suggested that NBS1 might regulate TopBP1 recruitment to the sites of DNA damage. TopBP1-depleted cells showed hypersensitivity to Mitomycin C and ionizing radiation, an increased frequency of sister-chromatid exchange level, and a reduced frequency of DNA double-strand break induced homologous recombination repair. Together, these results suggested that TopBP1 might be a mediator of DNA damage signaling from NBS1 to ATR and promote homologous recombination repair.

  14. 3BP2-deficient mice are osteoporotic with impaired osteoblast and osteoclast functions

    PubMed Central

    Levaot, Noam; Simoncic, Paul D.; Dimitriou, Ioannis D.; Scotter, Andrew; La Rose, Jose; Ng, Adeline H.M.; Willett, Thomas L.; Wang, Chiachien J.; Janmohamed, Salima; Grynpas, Marc; Reichenberger, Ernst; Rottapel, Robert

    2011-01-01

    A fine balance between bone resorption by osteoclasts and bone formation by osteoblasts maintains bone homeostasis. In patients with cherubism, gain-of-function mutations in 3BP2, which is encoded by SH3-domain binding protein 2 (SH3BP2), cause cystic lesions with activated osteoclasts that lead to craniofacial abnormalities. However, little is known about the function of wild-type 3BP2 in regulating bone homeostasis. Here we have shown that 3BP2 is required for the normal function of both osteoblasts and osteoclasts. Initial analysis showed that Sh3bp2–/–mice developed osteoporosis as a result of reduced bone formation despite the fact that bone resorption was impaired. We demonstrated using reciprocal bone marrow chimeras, a cell-intrinsic defect of the osteoblast and osteoclast compartments in vivo. Further, Sh3bp2–/– osteoblasts failed to mature and form mineralized nodules in vitro, while Sh3bp2–/– osteoclasts spread poorly and were unable to effectively degrade dentine matrix in vitro. Finally, we showed that 3BP2 was required for Abl activation in osteoblasts and Src activation in osteoclasts, and demonstrated that the in vitro defect of each cell type was restored by the respective expression of activated forms of these kinases. These findings reveal an unanticipated role for the 3BP2 adapter protein in osteoblast function and in coordinating bone homeostatic signals in both osteoclast and osteoblast lineages. PMID:21765218

  15. G3BP1 contributes to tumor metastasis via upregulation of Slug expression in hepatocellular carcinoma

    PubMed Central

    Dou, Ning; Chen, Jingde; Yu, Shijun; Gao, Yong; Li, Yandong

    2016-01-01

    RasGAP SH3-domain-Binding Protein 1 (G3BP1) has been implicated in cell growth, migration, and metastasis of some cancers, yet its function in hepatocellular carcinoma (HCC) remains to be explored. In the present study, we reported that G3BP1 was upregulated in HCC tissues compared with adjacent non-cancerous liver tissues both in mRNA and protein levels, and its high expression was significantly correlated with poor prognosis of HCC patients. Functional analyses demonstrated that forced expression of G3BP1 in HCC cells promoted cell migration, and silenced expression of G3BP1 by RNA interference caused opposite effects. Moreover, G3BP1 knockdown attenuated the distant metastasis capacity of HCC cells through tail vein injection approach in nude mice model. At molecular mechanism, we found G3BP1 knockdown decreased Slug expression, and increased the expression of the epithelial cell marker E-cadherin. Overexpression of Slug could restore the phenotype of G3BP1 silencing induced cell migration inhibition. Together, our data establish G3BP1 as an oncogenic factor involved in the metastasis of HCC and suggest that G3BP1 might serve as a novel predictor for patients’ outcome. PMID:27904777

  16. Distribution of HLA-G 14-bp insertion/deletion polymorphism in six Chinese ethnic groups.

    PubMed

    Tao, Y; Chen, J; Yao, Y; Shi, L; Lin, K; Huang, X; Dong, Z; Chu, J; Shi, L

    2013-04-01

    Recently, a 14-bp insertion/deletion polymorphism (+14 bp/-14 bp) in exon 8 of the Human leucocyte antigen-G (HLA-G) gene has been studied extensively because this polymorphism has been associated with HLA-G mRNA stability and could influence HLA-G mRNA expression. We investigated the distribution of the 14-bp insertion/deletion polymorphism in six different Chinese ethnic groups (Bulang, Wa, Hani, Jinuo, Maonan and Zhuang), which originated from three major ancient tribes (Di-Qiang, Baipu and Baiyue) in China. Comparison of the 14-bp insertion frequency in the six groups with other Chinese groups showed marked variation among the three ancient tribes, Di-Qing (0.490-0.534), Baipu (0.470-0.609) and Baiyue (0.280-0.344). Furthermore, the frequencies of the 14-bp insertion were similar in groups that came from the same ancient tribe, which indicated that the individuals who share the 14-bp insertion have the most probably inherited the 14-bp element from a common ancestor. In addition, an intra-tribal comparison of the 14-bp insertion/deletion frequencies between the descendants of the ancient ancestral tribes suggests that population histories or some environmental effects, such as founder effect or isolation, might also influence the distribution.

  17. The relationship between prenatal exposure to BP-3 and Hirschsprung's disease.

    PubMed

    Huo, Weiwei; Cai, Peng; Chen, Minjian; Li, Hongxing; Tang, Junwei; Xu, Chao; Zhu, Dongmei; Tang, Weibing; Xia, Yankai

    2016-02-01

    Hirschsprung's disease (HSCR) is neonatal intestinal abnormality which derived from the faliure of enteric neural crest cells migration to hindgut during embryogenesis from 5 to 12 weeks. Currenly, the knowledge of environmental factors contributing to HSCR is still scarce. Benzophenone-3 (BP-3) is one of the most widely used UV filters, and has weak estrogen and strong anti-androgenic effects. In order to examine the effect of maternal BP-3 exposure on development of offspring and explore the potential mechanism, we conducted case and control study and in vitro study. In this work, BP-3 concertrations in maternal urine was detected by ultra-high performance liquid chromatography. Besides, we investigated the cytotoxicity and receptor tyrosine kinase (RET) expression in cells exposed to BP-3. The results showed that maternal BP-3 exposure was associated with offspring's HSCR in the population as well as inhibited migration of 293T and SH-SY5Y cells. What's more, we discovered dose-response relationship between RET expression and BP-3 exposure dose, and miR-218 and some other genes involved in SLIT2/ROBO1-miR-218-RET/PLAG1 pathway were also related to BP-3 exposure. Therefore, we deduced that BP-3 influenced cell migration via SLIT2/ROBO1-miR-218-RET/PLAG1 pathway. Our study firstly revealed the relationship between maternal BP-3 exposure and HSCR as well as its potential mechanism.

  18. Transduced PEP-1-FK506BP ameliorates atopic dermatitis in NC/Nga mice.

    PubMed

    Kim, So Young; Sohn, Eun Jeong; Kim, Dae Won; Jeong, Hoon Jae; Kim, Mi Jin; Kang, Hye Won; Shin, Min Jea; Ahn, Eun Hee; Kwon, Soon Won; Kim, Young Nam; Kwon, Hyung Joo; Kim, Tae-Yoon; Lee, Kil Soo; Park, Jinseu; Eum, Won Sik; Choi, Soo Young

    2011-07-01

    Immunophilin, FK506-binding protein 12 (FK506BP), is a receptor protein for the immunosuppressive drug FK506 by the FK506BP/FK506 complex. However, the precise function of FK506BP in inflammatory diseases remains unclear. Therefore, we examined the protective effects of FK506BP on atopic dermatitis (AD) in tumor necrosis factor-α (TNF-α)/interferon-γ (IFN-γ)-induced HaCaT cells and 2,4-dinitrofluorobenzene-induced AD-like dermatitis in Nishiki-nezumi Cinnamon/Nagoya (NC/Nga) mice using a cell-permeable PEP-1-FK506BP. Transduced PEP-1-FK506BP significantly inhibited the expression of cytokines, as well as the activation of NF-κB and mitogen-activated protein kinase (MAPK) in TNF-α/IFN-γ-induced HaCaT cells. Furthermore, topical application of PEP-1-FK506BP to NC/Nga mice markedly inhibited AD-like dermatitis as determined by a histological examination and assessment of serum IgE levels, as well as cytokines and chemokines. These results indicate that PEP-1-FK506BP inhibits NF-κB and MAPK activation in cells and AD-like skin lesions by reducing the expression levels of cytokines and chemokines, thus suggesting that PEP-1-FK506BP may be a potential therapeutic agent for AD.

  19. An analysis of the rapidly rotating Bp star HD 133880

    NASA Astrophysics Data System (ADS)

    Bailey, J. D.; Grunhut, J.; Shultz, M.; Wade, G.; Landstreet, J. D.; Bohlender, D.; Lim, J.; Wong, K.; Drake, S.; Linsky, J.

    2012-06-01

    HD 133880 is a rapidly rotating chemically peculiar B-type (Bp) star (v sin i≃ 103 km s-1) and is host to one of the strongest magnetic fields of any Ap/Bp star. A member of the Upper Centaurus Lupus association, it is a star with a well-determined age of 16 Myr. 12 new spectra, four of which are polarimetric, obtained from the FEROS, ESPaDOnS and HARPS instruments, provide sufficient material from which to re-evaluate the magnetic field and obtain a first approximation to the atmospheric abundance distributions of He, O, Mg, Si, Ti, Cr, Fe, Ni, Pr and Nd. An abundance analysis was carried out using ZEEMAN, a program which synthesizes spectral line profiles for stars with permeating magnetic fields. The magnetic field structure was characterized by a colinear multipole expansion from the observed variations of the longitudinal and surface fields with rotational phase. Both magnetic hemispheres are clearly visible during the stellar rotation, and thus a three-ring abundance distribution model encompassing both magnetic poles and magnetic equator with equal spans in colatitude was adopted. Using the new magnetic field measurements and optical photometry together with previously published data, we refine the period of HD 133880 to P= 0.877 476 ± 0.000 009 d. Our simple axisymmetric magnetic field model is based on a predominantly quadrupolar component that roughly describes the field variations. Using spectrum synthesis, we derived mean abundances for O, Mg, Si, Ti, Cr, Fe and Pr. All elements, except Mg, are overabundant compared to the Sun. Mg appears to be approximately uniform over the stellar surface, while all other elements are more abundant in the negative magnetic hemisphere than in the positive magnetic hemisphere. In contrast to most Ap/Bp stars which show an underabundance in O, in HD 133880 this element is clearly overabundant compared to the solar abundance ratio. In studying the Hα and Paschen lines in the optical spectra, we could not unambiguously

  20. Interpretation of distributions on Kpi0 in pFe, nFe, and piFe interactions at 0.5-5.0 TeV in the framework of contemporary models

    NASA Astrophysics Data System (ADS)

    Avakyan, V. V.; Garyaka, A. P.; Zazyan, G. Z.

    Fluctuations of the observable parameters of nuclear electromagnetic cascades induced by 0.5-5.0 TeV cosmic ray protons, neutrons and pions are studied by the ionization calorimeter of the PION setup. The distributions of the inelasticity coefficient Kpi0 are measured for pFe, nFe and (pi)Fe interactions and compared with the predictions of various models. The probability of the inelastic charge exchange reaction in the (pi)Fe interactions is defined.

  1. Improved multiferroic properties in (1-x)BiFeO3-xBaTi0.95(Yb0.5Nb0.5)0.05O3 system (0≤x≤0.3)

    NASA Astrophysics Data System (ADS)

    Amouri, A.; Abdelmoula, N.; Khemakhem, H.

    2016-11-01

    Polycrystalline samples of (1-x)BiFeO3-xBaTi0.95(Yb0.5Nb0.5)0.05O3 (x=0, 0.1, 0.2 and 0.3) were prepared by the conventional solid state reaction method. The phase purity and composition were cheeked using powder X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS). The grain size and morphology of the ceramics were confirmed by scanning electron microscopy (SEM). X-ray diffraction showed that these compounds crystallized, at room temperature, in the Rhomboedral R3c for x=0 and in tetragonal P4mm for compositions 0.1≤x≤0.3 distorted perovskite structures. The BaTi0.95(Yb0.5Nb0.5)0.05O3 substitution led to an improvement of magnetic and ferroelectric properties at room temperature. The highest magnetization was reported for composition x=0.2 which was due to the enhancement of canting angles and the suppression of cycloid spin structure, as confirmed by 57Fe Mössbauer spectroscopy and the presence of Fe2+, as detected by XPS. The electric polarization increased significantly for doped samples, which proves the enhancement of the ferroelectric behavior and resistivity of our ceramics. Large electric field induced strains were observed for 0.7BiFeO3-0.3BaTi0.95(Yb0.5Nb0.5)0.05O3, as an evidence of piezoelectric behavior. These results show that BaTi0.95(Yb0.5Nb0.5)0.05O3 doped BiFeO3 is a promising multiferroic material.

  2. Effect of minor Cu addition on phase evolution and magnetic properties of {[(Fe0.5Co0.5)0.75Si0.05B0.20]0.96Nb0.04}100-x Cux alloys

    NASA Astrophysics Data System (ADS)

    Li, R.; Stoica, M.; Eckert, J.

    2009-01-01

    {[(Fe0.5Co0.5)0.75Si0.05B0.20]0.96Nb0.04}100-xCux (x = 0, 1, 1.5 and 2) alloys with different rapid solidification conditions were prepared by copper mold casting and melt spinning. The structures, the thermal and the magnetic properties were studied by X-ray diffraction, differential scanning calorimetry and vibrating sample magnetometry, respectively. Minor Cu addition obviously depresses the glass-forming ability of the alloys (critical glassy diameter dc < 1 mm) compared with [(Fe0.5Co0.5)0.75Si0.05B0.20]96 Nb4 (dc = 3 mm). The effect of Cu addition on the evolution of crystalline phases corresponding to different rapid solidification conditions was evaluated. The existence of (Fe,Co), (Fe,Co)3B, (Fe,Co)2B and (Fe,Co)23B6 crystalline phases in {[(Fe0.5Co0.5)0.75Si0.05B0.20]0.96 Nb0.04}100-x Cux alloys influences the saturation magnetization compared with the corresponding glassy alloys.

  3. Design and characterization of novel antimicrobial peptides, R-BP100 and RW-BP100, with activity against Gram-negative and Gram-positive bacteria.

    PubMed

    Torcato, Inês M; Huang, Yen-Hua; Franquelim, Henri G; Gaspar, Diana; Craik, David J; Castanho, Miguel A R B; Troeira Henriques, Sónia

    2013-03-01

    BP100 is a short cationic antimicrobial peptide with a mechanism of action dependent on peptide-lipid interactions and microbial surface charge neutralization. Although active against Gram-negative bacteria, BP100 is inactive against Gram-positive bacteria. In this study we report two newly designed BP100 analogues, RW-BP100 and R-BP100 that have the Tyr residue replaced with a Trp and/or the Lys residues replaced with an Arg. The new analogues in addition to being active against Gram-negative bacteria, possess activity against all tested Gram-positive bacteria. Mechanistic studies using atomic force microscopy, surface plasmon resonance and fluorescence methodologies reveal that the antibacterial efficiency follows the affinity for bacterial membrane. The studies suggest that the activity of BP100 and its analogues against Gram-negative bacteria is mainly driven by electrostatic interactions with the lipopolysaccharide layer and is followed by binding to and disruption of the inner membrane, whereas activity against Gram-positive bacteria, in addition to electrostatic attraction to the exposed lipoteichoic acids, requires an ability to more deeply insert in the membrane environment, which is favoured with Arg residues and is facilitated in the presence of a Trp residue. Knowledge on the mechanism of action of these antimicrobial peptides provides information that assists in the design of antimicrobials with higher efficacy and broader spectra of action, but also on the design of peptides with higher specificity if required.

  4. BP, cardiovascular disease, and death in the Folic Acid for Vascular Outcome Reduction in Transplantation trial.

    PubMed

    Carpenter, Myra A; John, Alin; Weir, Matthew R; Smith, Stephen R; Hunsicker, Lawrence; Kasiske, Bertram L; Kusek, John W; Bostom, Andrew; Ivanova, Anastasia; Levey, Andrew S; Solomon, Scott; Pesavento, Todd; Weiner, Daniel E

    2014-07-01

    The optimal BP level in kidney transplant recipients remains uncertain. This post hoc analysis of the Folic Acid for Vascular Outcome Reduction in Transplantation (FAVORIT) trial cohort assessed associations of BP with a pooled cardiovascular disease (CVD) outcome and with all-cause mortality. In 3474 prevalent kidney transplant patients, mean age was 52±9 years, 63% were men, 76% were white, 20% had a history of CVD, 40% had a history of diabetes mellitus, and the median time since transplant was 4.1 years (25th to 75th percentiles, 1.7-7.4); mean systolic BP was 136±20 mmHg and mean diastolic BP was 79±12 mmHg. There were 497 CVD events and 406 deaths. After adjustment for demographic and transplant characteristics and CVD risk factors, each 20-mmHg increase in baseline systolic BP associated with a 32% increase in subsequent CVD risk (hazard ratio [HR], 1.32; 95% confidence interval [95% CI], 1.19 to 1.46) and a 13% increase in mortality risk (HR, 1.13; 95% CI, 1.01 to 1.27). Similarly, after adjustment, at diastolic BP levels<70 mmHg, each 10-mmHg decrease in diastolic BP level associated with a 31% increase in CVD risk (HR, 1.31; 95% CI, 1.06 to 1.62) and a 31% increase in mortality risk (HR, 1.31; 95% CI, 1.03 to 1.66). However, at diastolic BP levels>70 mmHg, there was no significant relationship between diastolic BP and outcomes. Higher systolic BP strongly and independently associated with increased risk of CVD and all-cause mortality, without evidence of a J shape, whereas only lower levels of diastolic BP associated with increased risk of CVD and death in this trial.

  5. The BP oil spill and the bounty of Plaquemines Parish.

    PubMed

    Fertel, Randy

    2011-01-01

    The source of 25 to 30 percent of America's seafood, the Mississippi River Delta's cornucopian world is now uncertain. And yet, even if shrimp, oysters, and finfish are unaffected by the BP Oil Spill - a big if - one can already reflect on the passing of the culture once built upon gathering them. For almost three centuries, levees made life possible along the riverbanks and in the wetlands beyond. Those same levees also ensured the wetlands would eventually melt away into the Gulf. Cutting off the silt left behind during annual river inundations subjected the fragile land to erosion. Sulfur, natural gas, and oil production companies dug twenty thousand miles of canals to gain more direct routes to their fields and to pump out their mineral wealth. This caused salt-water intrusion that killed off plant life and caused more erosion. The world that sustained my Plaquemines ancestors was less subject to collapse following disasters not only because the ecosystem before the wetlands' ongoing loss was then more vibrant, complex, and robust; but also because their lives, especially their culinary lives, were more vibrant, complex, and robust. Life was hard, but when it came to putting food on the table, life followed the seasons.

  6. Benzo[a]pyrene (BP) DNA adduct formation in DNA repair-deficient p53 haploinsufficient [Xpa(-/-)p53(+/-)] and wild-type mice fed BP and BP plus chlorophyllin for 28 days.

    PubMed

    John, Kaarthik; Pratt, M Margaret; Beland, Frederick A; Churchwell, Mona I; McMullen, Gail; Olivero, Ofelia A; Pogribny, Igor P; Poirier, Miriam C

    2012-11-01

    We have evaluated DNA damage (DNA adduct formation) after feeding benzo[a]pyrene (BP) to wild-type (WT) and cancer-susceptible Xpa(-/-)p53(+/-) mice deficient in nucleotide excision repair and haploinsufficient for the tumor suppressor p53. DNA damage was evaluated by high-performance liquid chromatography/electrospray ionization tandem mass spectrometry (HPLC/ES-MS/MS), which measures r7,t8,t9-trihydroxy-c-10-(N (2)-deoxyguanosyl)-7,8,9,10-tetrahydrobenzo[a]pyrene (BPdG), and a chemiluminescence immunoassay (CIA), using anti-r7,t8-dihydroxy-t-9,10-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene (BPDE)-DNA antiserum, which measures both BPdG and the other stable BP-DNA adducts. When mice were fed 100 ppm BP for 28 days, BP-induced DNA damage measured in esophagus, liver and lung was typically higher in Xpa(-/-)p53(+/-) mice, compared with WT mice. This result is consistent with the previously observed tumor susceptibility of Xpa(-/-)p53(+/-) mice. BPdG, the major DNA adduct associated with tumorigenicity, was the primary DNA adduct formed in esophagus (a target tissue in the mouse), whereas total BP-DNA adducts predominated in higher levels in the liver (a non-target tissue in the mouse). In an attempt to lower BP-induced DNA damage, we fed the WT and Xpa(-/-)p53(+/-) mice 0.3% chlorophyllin (CHL) in the BP-containing diet for 28 days. The addition of CHL resulted in an increase of BP-DNA adducts in esophagus, liver and lung of WT mice, a lowering of BPdG in esophagi of WT mice and livers of Xpa(-/-)p53(+/-) mice and an increase of BPdG in livers of WT mice. Therefore, the addition of CHL to a BP-containing diet showed a lack of consistent chemoprotective effect, indicating that oral CHL administration may not reduce PAH-DNA adduct levels consistently in human organs.

  7. The Plerionic Supernova Remnant G21.5-0.9 Powered by PSR J1833-1034: New Spectroscopic and Imaging Results Revealed with the Chandra X-ray Observatory

    NASA Astrophysics Data System (ADS)

    Matheson, Heather; Safi-Harb, Samar

    2010-11-01

    In 1999, the Chandra X-ray Observatory revealed a 150'' radius halo surrounding the 40'' radius pulsar wind nebula (PWN) G21.5-0.9. A 2005 imaging study of G21.5-0.9 showed that the halo is limb-brightened and suggested that this feature is a candidate for the long-sought supernova remnant (SNR) shell. We present a spectral analysis of SNR G21.5-0.9, using the longest effective observation to date (578.6 ks with the Advanced CCD Imaging Spectrometer (ACIS) and 278.4 ks with the High-Resolution Camera (HRC)) to study unresolved questions about the spectral nature of remnant features, such as the limb brightening of the X-ray halo and the bright knot in the northern part of the halo. The Chandra analysis favors the non-thermal interpretation of the limb. Its spectrum is fit well with a power-law model with a photon index Γ = 2.13 (1.94-2.33) and a luminosity of Lx (0.5-8 keV) = (2.3 ± 0.6) × 1033 erg s-1 (at an assumed distance of 5.0 kpc). An srcut model was also used to fit the spectrum between the radio and X-ray energies. While the absence of a shell in the radio still prohibits constraining the spectrum at radio wavelengths, we assume a range of spectral indices to infer the 1 GHz flux density and the rolloff frequency of the synchrotron spectrum in X-rays and find that the maximum energy to which electrons are accelerated at the shock ranges from ~60 to 130 TeV (B/10 μG)-1/2, where B is the magnetic field in units of μG. For the northern knot, we constrain previous models and find that a two-component power-law (or srcut) + pshock model provides an adequate fit, with the pshock model requiring a very low ionization timescale and solar abundances for Mg and Si. Our spectroscopic study of PSR J1833-1034, the highly energetic pulsar powering G21.5-0.9, shows that its spectrum is dominated by hard non-thermal X-ray emission with some evidence of a thermal component that represents ~9% of the observed non-thermal emission and that suggests non-standard rapid

  8. 75 FR 65309 - National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-22

    ... National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling AGENCY: Department of... meeting of the National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling (the... Charter of the Commission can be found at: http://www.OilSpillCommission.gov . DATES: November 8, 2010,...

  9. 75 FR 37783 - National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-30

    ... National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling AGENCY: Department of... meeting of the National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling (the... spill and develop options to guard against, and mitigate the impact of, any oil spills associated...

  10. 75 FR 39518 - National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling; Correction

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-09

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling; Correction AGENCY: Office..., 2010, of the National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling, (75...

  11. 75 FR 47584 - National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-06

    ... National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling AGENCY: Department of... meeting for the National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling (the... Charter of the Commission can be found at: http://www.OilSpillCommission.gov . DATES: Wednesday, August...

  12. 75 FR 60097 - National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-29

    ... National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling AGENCY: Department of... meeting of the National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling (the... Charter of the Commission can be found at: http://www.OilSpillCommission.gov . DATES: Wednesday,...

  13. 75 FR 56526 - National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-16

    ... National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling AGENCY: Department of... meeting of the National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling (the... Charter of the Commission can be found at: http://www.OilSpillCommission.gov . DATES: Monday, September...

  14. 75 FR 29397 - National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-26

    ... Order 13543 of May 21, 2010 National Commission on the BP Deepwater Horizon Oil Spill and Offshore... National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling (the ``Commission''). Sec... against, and mitigating the impact of, oil spills associated with offshore drilling, taking...

  15. 53BP1 contributes to regulation of autophagic clearance of mitochondria.

    PubMed

    Youn, Cha Kyung; Kim, Hong Beum; Wu, Ting Ting; Park, Sanggon; Cho, Sung Il; Lee, Jung-Hee

    2017-03-27

    Autophagy, the primary recycling pathway within cells, plays a critical role in mitochondrial quality control under normal growth conditions and in the cellular response to stress. Here we provide evidence that 53BP1, a DNA damage response protein, is involved in regulating mitochondrial clearance from the cell via a type of autophagy termed mitophagy. We found that when either human or mouse cells were 53BP1-deficient, there was an increase in mitochondrial abnormalities, as observed through staining intensity, aggregation, and increased mass. Moreover, a 53BP1-depleted cell population included an increased number of cells with a high mitochondrial membrane potential (ΔΨm) relative to controls, suggesting that the loss of 53BP1 prevents initiation of mitophagy thereby leading to the accumulation of damaged mitochondria. Indeed, both 53BP1 and the mitophagy-associated protein LC3 translocated to mitochondria in response to damage induced by the mitochondrial uncoupler carbonyl cyanide m-chlorophenylhydrazone (CCCP). The recruitment of parkin, an E3-ubiquitin ligase, to mitochondria in response to CCCP treatment was significantly decreased in 53BP1-deficient cells. And lastly, using p53-deficient H1299 cells, we confirmed that the role of 53BP1 in mitophagy is independent of p53. These data support a model in which 53BP1 plays an important role in modulating mitochondrial homeostasis and in the clearance of damaged mitochondria.

  16. 75 FR 68607 - BP Canada Energy Marketing Corp. Apache Corporation; Notice for Temporary Waivers

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-08

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission BP Canada Energy Marketing Corp. Apache Corporation; Notice for Temporary Waivers November 1, 2010. Take notice that on October 29, 2010, BP Canada Energy Marketing Corp....

  17. Overexpressed CacyBP/SIP leads to the suppression of growth in renal cell carcinoma

    SciTech Connect

    Sun, Shiren; Ning, Xiaoxuan; Liu, Jie; Liu, Lili; Chen, Yu; Han, Shuang; Zhang, Yanqi; Liang, Jie; Wu, Kaichun; Fan, Daiming . E-mail: fandaim@fmmu.edu.cn

    2007-05-18

    Calcyclin-binding protein/Siah-1-interacting protein (CacyBP/SIP), a target protein of S100, has been identified as a component of a novel ubiquitinylation complex leading to {beta}-catenin degradation, which was found to be related to the malignant phenotypes of gastric cancer. However, the roles of CacyBP/SIP in renal cell carcinoma still remain unclear. In the present study, we had analyzed the expression of the CacyBP/SIP protein in human renal cancer cells and clinical tissue samples. The possible roles of CacyBP/SIP in regulating the malignant phenotype of renal cancer cells were also investigated. The results demonstrated that the expression of CacyBP/SIP was markedly down-regulated in renal cell carcinoma tissues and cell lines. Ectopic overexpression of CacyBP/SIP in A498 cells inhibited the proliferation of this cell and delayed cell cycle progression significantly, which might be related to the down-regulation of Cyclin D1 through reducing {beta}-catenin protein. CacyBP/SIP also suppressed colony formation in soft agar and its tumorigenicity in nude mice. Taken together, our work showed that CacyBP/SIP, as a novel down-regulated gene in renal cell carcinoma, suppressed proliferation and tumorigenesis of renal cancer cells.

  18. 76 FR 69712 - Application To Export Electric Energy; BP Energy Company

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-09

    ... Application To Export Electric Energy; BP Energy Company AGENCY: Office of Electricity Delivery and Energy... its authority to transmit electric energy from the United States to Canada pursuant to section 202(e... (DOE) issued Order No. EA-315, which authorized BP Energy to transmit electric energy from the...

  19. 76 FR 69713 - Application To Export Electric Energy; BP Energy Company

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-09

    ... Application To Export Electric Energy; BP Energy Company AGENCY: Office of Electricity Delivery and Energy... its authority to transmit electric energy from the United States to Mexico pursuant to section 202(e... Order No. EA-314, which authorized BP Energy to transmit electric energy from the United States...

  20. Preparation of PLLA/bpV(pic) microspheres and their effect on nerve cells.

    PubMed

    Lin, Qiang; Chen, Hai-yun; Li, Hao-shen; Cai, Yang-ting

    2014-02-01

    In this study, we prepared PLLA/bpV(pic) microspheres, a bpV(pic) controlled release system and examined their ability to protect nerve cells and promote axonal growth. PLLA microspheres were prepared by employing the o/w single emulsification-evaporation technique. Neural stem cells and dorsal root ganglia were divided into 3 groups in terms of the treatment they received: a routine medium group (cultured in DMEM), a PLLA microsphere group (DMEM containing PLLA microspheres alone) and a PLLA/bpV(pic) group [DMEM containing PLLA/bpV(pic) microspheres]. The effects of PLLA/bpV(pic) microspheres were evaluated by the live-dead test and measurement of axonal length. Our results showed that PLLA/bpV(pic) granulation rate was (88.2±5.6)%; particle size was (16.8±3.1)%, drug loading was (4.05±0.3)%; encapsulation efficiency was (48.5±1.8)%. The release time lasted for 30 days. In PLLA/bpV(pic) microsphere group, the cell survival rate was (95.2 ±4.77)%, and the length of dorsal root ganglion (DRG) was 718±95 μm, which were all significantly greater than those in ordinary routine medium group and PLLA microsphere group. This preliminary test results showed the PLLA/bpV(pic) microspheres were successfully prepared and they could promote the survival and growth of neural cells in DRG.

  1. Overexpressed CacyBP/SIP leads to the suppression of growth in renal cell carcinoma.

    PubMed

    Sun, Shiren; Ning, Xiaoxuan; Liu, Jie; Liu, Lili; Chen, Yu; Han, Shuang; Zhang, Yanqi; Liang, Jie; Wu, Kaichun; Fan, Daiming

    2007-05-18

    Calcyclin-binding protein/Siah-1-interacting protein (CacyBP/SIP), a target protein of S100, has been identified as a component of a novel ubiquitinylation complex leading to beta-catenin degradation, which was found to be related to the malignant phenotypes of gastric cancer. However, the roles of CacyBP/SIP in renal cell carcinoma still remain unclear. In the present study, we had analyzed the expression of the CacyBP/SIP protein in human renal cancer cells and clinical tissue samples. The possible roles of CacyBP/SIP in regulating the malignant phenotype of renal cancer cells were also investigated. The results demonstrated that the expression of CacyBP/SIP was markedly down-regulated in renal cell carcinoma tissues and cell lines. Ectopic overexpression of CacyBP/SIP in A498 cells inhibited the proliferation of this cell and delayed cell cycle progression significantly, which might be related to the down-regulation of Cyclin D1 through reducing beta-catenin protein. CacyBP/SIP also suppressed colony formation in soft agar and its tumorigenicity in nude mice. Taken together, our work showed that CacyBP/SIP, as a novel down-regulated gene in renal cell carcinoma, suppressed proliferation and tumorigenesis of renal cancer cells.

  2. CacyBP/SIP as a novel modulator of the thin filament.

    PubMed

    Jurewicz, Ewelina; Ostrowska, Zofia; Jozwiak, Jolanta; Redowicz, Maria Jolanta; Lesniak, Wieslawa; Moraczewska, Joanna; Filipek, Anna

    2013-03-01

    The CacyBP/SIP protein interacts with several targets, including actin. Since the majority of actin filaments are associated with tropomyosin, in this work we characterized binding of CacyBP/SIP to the actin-tropomyosin complex and examined the effects of CacyBP/SIP on actin filament functions. By using reconstituted filaments composed of actin and AEDANS-labeled tropomyosin, we observed that binding of CacyBP/SIP caused an increase in tropomyosin fluorescence intensity indicating the occurrence of conformational changes within the filament. We also found that CacyBP/SIP bound directly to tropomyosin and that these proteins did not compete with each other for binding to actin. Electron microscopy showed that in the absence of tropomyosin CacyBP/SIP destabilized actin filaments, but tropomyosin reversed this effect. Actin-activated myosin S1 ATPase activity assays, performed using a colorimetric method, indicated that CacyBP/SIP reduced ATPase activity and that the presence of tropomyosin enhanced this inhibitory effect. Thus, our results suggest that CacyBP/SIP, through its interaction with both actin and tropomyosin, regulates the organization and functional properties of the thin filament.

  3. CacyBP/SIP promotes the proliferation of colon cancer cells.

    PubMed

    Zhai, Huihong; Shi, Yongquan; Chen, Xiong; Wang, Jun; Lu, Yuanyuan; Zhang, Faming; Liu, Zhengxiong; Lei, Ting; Fan, Daiming

    2017-01-01

    CacyBP/SIP is a component of the ubiquitin pathway and is overexpressed in several transformed tumor tissues, including colon cancer, which is one of the most common cancers worldwide. It is unknown whether CacyBP/SIP promotes the proliferation of colon cancer cells. This study examined the expression level, subcellular localization, and binding activity of CacyBP/SIP in human colon cancer cells in the presence and absence of the hormone gastrin. We found that CacyBP/SIP was expressed in a high percentage of colon cancer cells, but not in normal colonic surface epithelium. CacyBP/SIP promoted the cell proliferation of colon cancer cells under both basal and gastrin stimulated conditions as shown by knockdown studies. Gastrin stimulation triggered the translocation of CacyBP/SIP to the nucleus, and enhanced interaction between CacyBP/SIP and SKP1, a key component of ubiquitination pathway which further mediated the proteasome-dependent degradation of p27kip1 protein. The gastrin induced reduction in p27kip1 was prevented when cells were treated with the proteasome inhibitor MG132. These results suggest that CacyBP/SIP may be promoting growth of colon cancer cells by enhancing ubiquitin-mediated degradation of p27kip1.

  4. MAP kinase p38 is a novel target of CacyBP/SIP phosphatase.

    PubMed

    Topolska-Woś, Agnieszka M; Rosińska, Sara; Filipek, Anna

    2017-03-10

    Mitogen-activated protein (MAP) kinases are important players in cellular signaling pathways. Recently, it has been shown that CacyBP/SIP serves as a phosphatase for one of the MAP kinases, ERK1/2. Through dephosphorylation of this kinase CacyBP/SIP modulates the transcriptional activity of Elk-1 and the activity of the CREB-BDNF pathway. In this work, using NB2a cell lysate and recombinant proteins, we show that CacyBP/SIP binds and dephosphorylates another member of the MAP kinase family, p38. Analysis of recombinant full-length CacyBP/SIP and its three major domains, N-terminal, middle CS and C-terminal SGS, indicates that the middle CS domain is responsible for p38 dephosphorylation. Moreover, we show that CacyBP/SIP might be implicated in response to oxidative stress. Dephosphorylation of phospho-p38 by CacyBP/SIP in NB2a cells treated with hydrogen peroxide is much more effective than in control ones. In conclusion, involvement of CacyBP/SIP in the regulation of p38 kinase activity, in addition to that of ERK1/2, might point to the function of CacyBP/SIP in pro-survival and pro-apoptotic pathways.

  5. SN 2015bp: adding to the growing population of transitional Type Ia supernovae

    NASA Astrophysics Data System (ADS)

    Srivastav, Shubham; Anupama, G. C.; Sahu, D. K.; Ravikumar, C. D.

    2017-04-01

    Photometric and spectroscopic observations of Type Ia supernova 2015bp are presented, spanning ∼-6 to ∼+141 d since B-band maximum. Also presented are unpublished HCT spectra of type Ia iPTF13ebh between -11 and +34 d since B-band maximum. SN 2015bp shows rapidly declining light curves with Δm15(B) = 1.72 ± 0.04. The I-band light curve shows a clear secondary maximum and peaks before the B-band maximum, placing SN 2015bp in the transitional category of SNe Ia. The spectral evolution of SN 2015bp resembles other transitional SNe Ia rather than 1991bg-like events. The C II λ6580 feature is detected in both SN 2015bp and iPTF13ebh, though it is present till the epoch of B-band maximum in the case of SN 2015bp. The velocity gradients of Si II λ6355 place SN 2015bp and iPTF13ebh in the FAINT subclass, whereas pseudo-equivalent widths of Si II features place them in the Cool (CL) subclass of SNe Ia. The bolometric light curve of SN 2015bp indicates that ∼0.2 M⊙ of 56Ni was synthesized in the explosion, with a total ejected mass of ∼0.9 M⊙, suggesting a sub-Chandrasekhar mass white dwarf progenitor.

  6. APP-BP1 inhibits Aβ42 levels by interacting with Presenilin-1

    PubMed Central

    Chen, Yuzhi; Bodles, Angela M; McPhie, Donna L; Neve, Rachael L; Mrak, Robert E; Griffin, W Sue T

    2007-01-01

    Background The β-amyloid precursor protein (APP) is sequentially cleaved by the β- and then γ-secretase to generate the amyloid β-peptides Aβ40 and Aβ42. Increased Aβ42/Aβ40 ratios trigger amyloid plaque formations in Alzheimer's disease (AD). APP binds to APP-BP1, but the biological consequence is not well understood. Results We report that when the endogenous APP-BP1 was suppressed by small interfering RNAs (siRNAs), cell-associated Aβ42 was dramatically increased in APP695 expressing primary neurons. The accumulation of Aβ42 was accompanied by significant increases in APP and APP-CTF in APP-BP1 siRNA expressing neurons. In contrast, APP-BP1 overexpression in primary neurons significantly decreased the levels of Aβ and endogenous APP but not APLPs. We also investigated the potential mechanism of APP-BP1-mediated APP processing. APP-BP1 co-precipitated with Presenilin-1 (PS1) in native rat brain extracts, co-migrated with the γ-secretase components in brain membrane extracts in glycerol gradient centrifugation, and colocalized in primary neurons. Further, the endogenous PS1-CTF was significantly downregulated by APP-BP1 expression. Conclusion Our data suggest that APP-BP1 may inhibit Aβ42 production by interacting with PS1 under physiological conditions. PMID:17286867

  7. 53BP1 contributes to regulation of autophagic clearance of mitochondria

    PubMed Central

    Youn, Cha Kyung; Kim, Hong Beum; Wu, Ting Ting; Park, Sanggon; Cho, Sung Il; Lee, Jung-Hee

    2017-01-01

    Autophagy, the primary recycling pathway within cells, plays a critical role in mitochondrial quality control under normal growth conditions and in the cellular response to stress. Here we provide evidence that 53BP1, a DNA damage response protein, is involved in regulating mitochondrial clearance from the cell via a type of autophagy termed mitophagy. We found that when either human or mouse cells were 53BP1-deficient, there was an increase in mitochondrial abnormalities, as observed through staining intensity, aggregation, and increased mass. Moreover, a 53BP1-depleted cell population included an increased number of cells with a high mitochondrial membrane potential (ΔΨm) relative to controls, suggesting that the loss of 53BP1 prevents initiation of mitophagy thereby leading to the accumulation of damaged mitochondria. Indeed, both 53BP1 and the mitophagy-associated protein LC3 translocated to mitochondria in response to damage induced by the mitochondrial uncoupler carbonyl cyanide m-chlorophenylhydrazone (CCCP). The recruitment of parkin, an E3-ubiquitin ligase, to mitochondria in response to CCCP treatment was significantly decreased in 53BP1-deficient cells. And lastly, using p53-deficient H1299 cells, we confirmed that the role of 53BP1 in mitophagy is independent of p53. These data support a model in which 53BP1 plays an important role in modulating mitochondrial homeostasis and in the clearance of damaged mitochondria. PMID:28345606

  8. CacyBP/SIP promotes the proliferation of colon cancer cells

    PubMed Central

    Chen, Xiong; Wang, Jun; Lu, Yuanyuan; Zhang, Faming; Liu, Zhengxiong; Lei, Ting; Fan, Daiming

    2017-01-01

    CacyBP/SIP is a component of the ubiquitin pathway and is overexpressed in several transformed tumor tissues, including colon cancer, which is one of the most common cancers worldwide. It is unknown whether CacyBP/SIP promotes the proliferation of colon cancer cells. This study examined the expression level, subcellular localization, and binding activity of CacyBP/SIP in human colon cancer cells in the presence and absence of the hormone gastrin. We found that CacyBP/SIP was expressed in a high percentage of colon cancer cells, but not in normal colonic surface epithelium. CacyBP/SIP promoted the cell proliferation of colon cancer cells under both basal and gastrin stimulated conditions as shown by knockdown studies. Gastrin stimulation triggered the translocation of CacyBP/SIP to the nucleus, and enhanced interaction between CacyBP/SIP and SKP1, a key component of ubiquitination pathway which further mediated the proteasome-dependent degradation of p27kip1 protein. The gastrin induced reduction in p27kip1 was prevented when cells were treated with the proteasome inhibitor MG132. These results suggest that CacyBP/SIP may be promoting growth of colon cancer cells by enhancing ubiquitin-mediated degradation of p27kip1. PMID:28196083

  9. Purification and functional properties of the membrane fissioning protein CtBP3/BARS.

    PubMed

    Valente, Carmen; Spanò, Stefania; Luini, Alberto; Corda, Daniela

    2005-01-01

    The fissioning protein CtBP3/BARS is a member of the CtBP transcription corepressor family of proteins. The characterization of this fissioning activity of CtBP3/BARS in both isolated Golgi membranes and in intact cells has indicated that the CtBP family includes multifunctional proteins that can act both in the nucleus and in the cytoplasm. The fissiogenic activity of CtBP3/BARS has a role in the fragmentation of the Golgi complex during mitosis and during intracellular membrane transport. This was demonstrated using a number of approaches and reagents, which are discussed in the following text, and which include recombinant proteins and mutants, antibodies, protein overexpression, RNA interference, antisense oligonucleotides, cell permeabilization, and electron miscroscopy, together with biochemical assays such as that for ADP-ribosylation.

  10. The adaptor 3BP2 is required for KIT receptor expression and human mast cell survival

    PubMed Central

    Ainsua-Enrich, Erola; Serrano-Candelas, Eva; Álvarez-Errico, Damiana; Picado, César; Sayós, Joan; Rivera, Juan; Martín, Margarita

    2015-01-01

    3BP2 is a cytoplasmic adaptor protein that acts as a positive regulator in mast cell FcεRI-dependent signaling. The KIT receptor whose ligand is the stem cell factor (SCF) is necessary for mast cell development, proliferation and survival as well as for optimal IgE-dependent signal. Activating mutations in KIT have been associated with several diseases including mastocytosis. In the present work, we found that 3BP2 silencing impairs KIT signaling pathways, thus affecting PI3K and MAP kinase pathways in human mast cells from HMC-1, LAD2 (human mast cell lines) and CD34+-derived mast cells. Unexpectedly, silencing of 3BP2 reduces KIT expression in normal human mast cells as well as in HMC-1 cells where KIT is mutated, thus increasing cellular apoptosis and caspase 3/7 activity. 3BP2 silencing reduces KIT transcription expression levels. Interestingly, 3BP2 silencing decreased MITF expression, a transcription factor involved in KIT expression. Reconstitution of 3BP2 in knockdown cells leads to reversal of KIT expression as well as survival phenotype. Accordingly MITF reconstitution enhances KIT expression levels in 3BP2 silenced cells. Moreover, downregulation of KIT expression by miRNA221 overexpression or the proteasome inhibitor bortezomib also reduced 3BP2 and MITF expression. Furthermore, KIT tyrosine activity inhibition reduced 3BP2 and MITF expression, demonstrating again a tight and reciprocal relationship between these molecules. Taken together, our results show that 3BP2 regulates human mast cell survival and participates in KIT-mediated signal transduction by directly controlling KIT receptor expression, suggesting its potential as a therapeutic target in mast cell-mediated inflammatory diseases and deregulated KIT disorders. PMID:25810396

  11. Centennial and millennial-scale hydroclimate changes in northwestern Patagonia since 16,000 yr BP

    NASA Astrophysics Data System (ADS)

    Moreno, Patricio I.; Videla, Javiera

    2016-10-01

    We examine hydroclimate changes at centennial/millennial timescales since 16,000 yr BP in northwestern Patagonia based on the pollen and charcoal record from Lago El Salto, a small closed-basin lake located in the Chilean Lake District (41°38‧48.02″S, 73° 5‧48.42″W). We observe cold/wet conditions between 14,500-16,000 yr BP, followed by further cooling with increased precipitation until 13,000 yr BP, enhanced precipitation seasonality and/or variability between 11,600-13,000 yr BP, and an extended warm-and-dry interval between 7600 and 11,300 yr BP with peak paleofire activity. Colder-and-wetter than present conditions and muted paleofire activity prevail between 5300 and 7600 yr BP, followed by alternating cold/wet and centennial-scale warm/dry phases starting at 5300 yr BP with three conspicuous megadroughts since 2500 yr BP. The most recent megadrought occurred during the Medieval Climate Anomaly. We identify a cold reversal that spans the Antarctic Cold Reversal (ACR) and the Younger Dryas (YD) chrons with stronger-than-present westerly influence during the former and enhanced variability during the latter. These results extend the northern limit of strong cooling and increase in precipitation during the ACR and the southern limit of influence of strong hydrologic variations during the YD in terrestrial environments, suggesting an overlap in the spheres of influence of processes originating from southern and northern polar latitudes. An extended warm southern westerly wind (SWW)-minimum interval is evident between 7600 and 11,300 yr BP, followed by a rapid shift to cool-moist conditions between 5300 and 7600 yr BP brought by a mid-Holocene SWW maximum. Since then we observe centennial-scale hydroclimate variability, which has driven biodiversity and fire-regime shifts of evergreen temperate rainforests.

  12. Benzo[a]pyrene (BP) DNA adduct formation in DNA repair–deficient p53 haploinsufficient [Xpa(−/−)p53(+/−)] and wild-type mice fed BP and BP plus chlorophyllin for 28 days

    PubMed Central

    Poirier, Miriam C.

    2012-01-01

    We have evaluated DNA damage (DNA adduct formation) after feeding benzo[a]pyrene (BP) to wild-type (WT) and cancer-susceptible Xpa(−/−)p53(+/−) mice deficient in nucleotide excision repair and haploinsufficient for the tumor suppressor p53. DNA damage was evaluated by high-performance liquid chromatography/electrospray ionization tandem mass spectrometry (HPLC/ES-MS/MS), which measures r7,t8,t9-trihydroxy-c-10-(N 2-deoxyguanosyl)-7,8,9,10-tetrahydrobenzo[a]pyrene (BPdG), and a chemiluminescence immunoassay (CIA), using anti-r7,t8-dihydroxy-t-9,10-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene (BPDE)–DNA antiserum, which measures both BPdG and the other stable BP-DNA adducts. When mice were fed 100 ppm BP for 28 days, BP-induced DNA damage measured in esophagus, liver and lung was typically higher in Xpa(−/−)p53(+/−) mice, compared with WT mice. This result is consistent with the previously observed tumor susceptibility of Xpa(−/−)p53(+/−) mice. BPdG, the major DNA adduct associated with tumorigenicity, was the primary DNA adduct formed in esophagus (a target tissue in the mouse), whereas total BP-DNA adducts predominated in higher levels in the liver (a non-target tissue in the mouse). In an attempt to lower BP-induced DNA damage, we fed the WT and Xpa(−/−)p53(+/−) mice 0.3% chlorophyllin (CHL) in the BP-containing diet for 28 days. The addition of CHL resulted in an increase of BP–DNA adducts in esophagus, liver and lung of WT mice, a lowering of BPdG in esophagi of WT mice and livers of Xpa(−/−)p53(+/−) mice and an increase of BPdG in livers of WT mice. Therefore, the addition of CHL to a BP-containing diet showed a lack of consistent chemoprotective effect, indicating that oral CHL administration may not reduce PAH–DNA adduct levels consistently in human organs. PMID:22828138

  13. Differential cross sections for scattering of 0.5-, 1.5-, and 5.0-keV hydrogen atoms by He, H2, N2, and O2

    NASA Technical Reports Server (NTRS)

    Newman, J. H.; Chen, Y. S.; Smith, K. A.; Stebbings, R. F.

    1986-01-01

    This paper reports measurements of absolute cross sections, differential in angle, for scattering of 0.5-, 1.5-, and 5.0-keV hydrogen atoms by He, H2, N2, and O2 at laboratory scattering angles between 0.1 and 5 deg. The measured cross sections are the sums of those for elastic and inelastic collisions having a fast H atom product and are needed for calculating energy transfer to the upper atmosphere from precipitating ring current particles.

  14. Validation of four devices: Omron M6 Comfort, Omron HEM-7420, Withings BP-800, and Polygreen KP-7670 for home blood pressure measurement according to the European Society of Hypertension International Protocol

    PubMed Central

    Topouchian, Jirar; Agnoletti, Davide; Blacher¹, Jacques; Youssef, Ahmed; Chahine, Mirna N; Ibanez, Isabel; Assemani, Nathalie; Asmar, Roland

    2014-01-01

    Background Four oscillometric devices, including the Omron M6 Comfort, Omron HEM-7420, Withings BP-800, and Polygreen KP-7670, designed for self-blood pressure measurement (SBPM) were evaluated according to the European Society of Hypertension (ESH) International Protocol Revision 2010 in four separate studies. Methods The four devices measure brachial blood pressure (BP) using the oscillometric method. The Withings BP-800 has to be connected to an Apple® iOS device such as an iPhone®, iPad®, or iPod®. The ESH International Protocol Revision 2010 includes a total number of 33 subjects. The difference between observer and device BP values was calculated for each measure. Ninety-nine pairs of BP differences were classified into three categories (≤5 mmHg, ≤10 mmHg, ≤15 mmHg). The protocol procedures were followed precisely in each of the four studies. Results All four tested devices passed the validation process. The mean differences between the device and mercury readings were: −1.8±5.1 mmHg and −0.4±2.8 mmHg for systolic and diastolic BP, respectively, using the Omron M6 Comfort device; 2.5±4.6 mmHg and −1.2±4.3 mmHg for the Omron HEM-7420 device; −0.2±5.0 mmHg and 0.4±4.2 mmHg for the Withings BP-800 device; and 3.0±5.3 mmHg and 0.3±5.2 mmHg for the Polygreen KP-7670 device. Conclusion Omron M6 Comfort, Omron HEM-7420, Withings BP-800, and Polygreen KP-7670 readings differing by less than 5 mmHg, 10 mmHg, and 15 mmHg fulfill the ESH International Protocol Revision 2010 requirements, and therefore are suitable for use by patients for SBPM, if used correctly. PMID:24476688

  15. Non-linear current-voltage characteristics of (La 0.5Eu 0.5) 0.7Pb 0.3MnO 3 single crystals: Possible manifestation of the internal heating of chargecarriers

    NASA Astrophysics Data System (ADS)

    Shaykhutdinov, K. A.; Popkov, S. I.; Balaev, D. A.; Semenov, S. V.; Bykov, A. A.; Dubrovskiy, A. A.; Sapronova, N. V.; Volkov, N. V.

    2010-12-01

    Temperature evolution of the current-voltage characteristics (CVCs) of a single-crystal lanthanum manganite (La 0.5Eu 0.5) 0.7Pb 0.3MnO 3 is investigated in a wide (up to 1 А) range of instrumental currents. Effects of a transport current and an applied electric field on the resistance of the material are studied in view of possible implementation of the charge ordering break in dielectric regions occurring due to phase separation in manganites. A negative differential resistance portion observed in the CVCs suggests the presence of a current switching effect. Below the temperature of the metal-dielectric transition in (La 0.5Eu 0.5) 0.7Pb 0.3MnO 3, the hysteresis is observed in the CVC. The detailed analysis of the internal sample heating on the basis of experimental data on thermal conductivity showed, however, that these CVC features can be explained within the concept of non-equilibrium heating of electron gas.

  16. Cell cycle-dependent inhibition of 53BP1 signaling by BRCA1

    PubMed Central

    Feng, Lin; Li, Nan; Li, Yujing; Wang, Jiadong; Gao, Min; Wang, Wenqi; Chen, Junjie

    2015-01-01

    DNA damage response mediator protein 53BP1 is a key regulator of non-homologous end-joining (NHEJ) repair. 53BP1 protects DNA broken ends from resection by recruiting two downstream factors, RIF1 (RAP1-interacting factor 1) and PTIP (Pax transactivation domain-interacting protein), to double-stranded breaks (DSBs) via ATM (ataxia telangiectasia mutated)-mediated 53BP1 phosphorylation, and competes with BRCA1-mediated homologous recombination (HR) repair in G1 phase. In contrast, BRCA1 antagonizes 53BP1-direct NHEJ repair in S/G2 phases. We and others have found that BRCA1 prevents the translocation of RIF1 to DSBs in S/G2 phases; however, the underlying mechanism remains unclear. Here we show that efficient ATM-dependent 53BP1 phosphorylation is restricted to the G1 phase of the cell cycle, as a consequence RIF1 and PTIP accumulation at DSB sites only occur in G1 phase. Mechanistically, both BRCT and RING domains of BRCA1 are required for the inhibition of 53BP1 phosphorylation in S and G2 phases. Thus, our findings reveal how BRCA1 antagonizes 53BP1 signaling to ensure that HR repair is the dominant repair pathway in S/G2 phases. PMID:27462418

  17. nArgBP2 as a hub molecule in the etiology of various neuropsychiatric disorders

    PubMed Central

    Lee, Sang-Eun; Chang, Sunghoe

    2016-01-01

    Recent studies have strongly implicated postsynaptic scaffolding proteins such as SAPAP3 or Shank3 in the pathogenesis of various mood disorders, including autism spectrum disorder, bipolar disorder (BD), and obsessive-compulsive disorders. Neural Abelson-related gene-binding protein 2 (nArgBP2) was originally identified as a protein that interacts with SAPAP3 and Shank3. Recent study shows that the genetic deletion of nArgBP2 in mice leads to manic/bipolar-like behavior resembling symptoms of BD. However, the function of nArgBP2 at synapse, or its connection with the synaptic dysfunctions, is completely unknown. This study provides compelling evidence that nArgBP2 regulates the spine morphogenesis through the activation of Rac1/WAVE/PAK/cofilin pathway, and that its ablation causes a robust and selective inhibition of excitatory synapse formation, by controlling actin dynamics. Our results revealed the underlying mechanism for the synaptic dysfunction caused by nArgBP2 downregulation that associates with analogous human BD. Moreover, since nArgBP2 interacts with key proteins involved in various neuropsychiatric disorders, our finding implies that nArgBP2 could function as a hub linking various etiological factors of different mood disorders. [BMB Reports 2016; 49(9): 457-458] PMID:27530683

  18. M2BP inhibits HIV-1 virion production in a vimentin filaments-dependent manner

    PubMed Central

    Wang, Qin; Zhang, Xiaolin; Han, Yuling; Wang, Xinlu; Gao, Guangxia

    2016-01-01

    M2BP (also called 90K) is an interferon-stimulated gene product that is upregulated in HIV-1 infection. A recent study revealed that M2BP reduces the infectivity of HIV-1 by inhibiting the processing of the viral envelope protein. Here we report that in addition to reducing viral infectivity, M2BP inhibits HIV-1 virion production. We provide evidence showing that M2BP inhibits HIV-1 Gag trafficking to the plasma membrane in a vimentin-dependent manner. When vimentin filaments were collapsed by treating cells with acrylamide or by overexpression of a dominant-negative mutant of vimentin, M2BP inhibition of HIV-1 virion production was significantly relieved. We further show that M2BP interacts with both HIV-1 Gag and vimentin and thereby mediates their interactions. We propose that M2BP traps HIV-1 Gag to vimentin filaments to inhibit the transportation of HIV-1 Gag to the plasma membrane. These findings uncover a novel mechanism by which a host antiviral factor inhibits HIV-1 virion production. PMID:27604950

  19. Tankyrase-binding protein TNKS1BP1 regulates actin cytoskeleton rearrangement and cancer cell invasion.

    PubMed

    Ohishi, Tomokazu; Yoshida, Haruka; Katori, Masamichi; Migita, Toshiro; Muramatsu, Yukiko; Miyake, Mao; Ishikawa, Yuichi; Saiura, Akio; Iemura, Shun-Ichiro; Natsume, Tohru; Seimiya, Hiroyuki

    2017-02-15

    Tankyrase, a poly(ADP-ribose) polymerase (PARP) that promotes telomere elongation and Wnt/β-catenin signaling, has various binding partners, suggesting that it has as-yet unidentified functions. Here we report that the tankyrase-binding protein TNKS1BP1 regulates actin cytoskeleton and cancer cell invasion, which is closely associated with cancer progression. TNKS1BP1 colocalized with actin filaments and negatively regulated cell invasion. In TNKS1BP1-depleted cells, actin filament dynamics, focal adhesion, and lamellipodia ruffling were increased with activation of the ROCK-LIMK-cofilin pathway. TNKS1BP1 bound the actin capping protein CapZA2. TNKS1BP1 depletion dissociated CapZA2 from the cytoskeleton, leading to cofilin phosphorylation and enhanced cell invasion. Tankyrase overexpression increased cofilin phosphorylation, dissociated CapZA2 from cytoskeleton, and enhanced cell invasion in a PARP activity-dependent manner. In clinical samples of pancreatic cancer, TNKS1BP1 expression was reduced in invasive regions. We propose that the tankyrase-TNKS1BP1 axis constitutes a post-translational modulator of cell invasion whose aberration promotes cancer malignancy.

  20. A new SBP-box gene BpSPL1 in silver birch (Betula pendula).

    PubMed

    Lännenpää, Mika; Jänönen, Isto; Hölttä-Vuori, Maarit; Gardemeister, Marika; Porali, Ilkka; Sopanen, Tuomas

    2004-03-01

    The SBP-box gene family represents a group of plant-specific genes encoding putative transcription factors. Thus far, SBP-domain protein binding sites have been found in the promoters of Arabidopsis APETALA1 and Antirrhinum SQUAMOSA. A putative SBP-domain binding element has been observed in the promoter of BpMADS5, a close homologue of Arabidopsis FRUITFULL in silver birch (Betula pendula). A novel SBP-box gene from birch named BpSPL1 has been cloned and characterized. The nucleotide sequence of BpSPL1 is similar to Antirrhinum SBP2 and Arabidopsis SPL3, apart from the unique finding that BpSPL1 does not contain an intron typical to all other known SBP-box genes studied thus far. According to Northern blot analysis, BpSPL1 is expressed in birch inflorescences as well as in shoots and leaves. Studies using electrophoretic mobility shift assay demonstrate that there are nuclear proteins in birch inflorescences which specifically bind to the SBP binding element of the promoter of BpMADS5. BpSPL1 expressed in Escherichia coli also specifically binds to this element. According to Southern blot analysis, there are at least two SBP-box genes in birch. The results suggest that SBP-box genes are involved in the regulation of flower development in birch.

  1. Establishing a Dynamic Self-Adaptation Learning Algorithm of the BP Neural Network and Its Applications

    NASA Astrophysics Data System (ADS)

    Li, Xiaofeng; Xiang, Suying; Zhu, Pengfei; Wu, Min

    2015-12-01

    In order to avoid the inherent deficiencies of the traditional BP neural network, such as slow convergence speed, that easily leading to local minima, poor generalization ability and difficulty in determining the network structure, the dynamic self-adaptive learning algorithm of the BP neural network is put forward to improve the function of the BP neural network. The new algorithm combines the merit of principal component analysis, particle swarm optimization, correlation analysis and self-adaptive model, hence can effectively solve the problems of selecting structural parameters, initial connection weights and thresholds and learning rates of the BP neural network. This new algorithm not only reduces the human intervention, optimizes the topological structures of BP neural networks and improves the network generalization ability, but also accelerates the convergence speed of a network, avoids trapping into local minima, and enhances network adaptation ability and prediction ability. The dynamic self-adaptive learning algorithm of the BP neural network is used to forecast the total retail sale of consumer goods of Sichuan Province, China. Empirical results indicate that the new algorithm is superior to the traditional BP network algorithm in predicting accuracy and time consumption, which shows the feasibility and effectiveness of the new algorithm.

  2. Dynamics of the earth magnetic field in the 10-75 kyr period comprising the Laschamp and Mono Lake excursions: New results from the French Chaîne des Puys in a global perspective

    NASA Astrophysics Data System (ADS)

    Laj, Carlo; Guillou, Hervé; Kissel, Catherine

    2014-02-01

    We report here on a new paleomagnetic (directions and intensities) and coupled K/Ar and 40Ar/39Ar analysis of 35 different flows, emplaced in the Chaîne des Puys during the 75 to 10 kyr interval, which contains the Mono Lake and Laschamp excursions. There is a remarkable agreement between the new set of absolute volcanic intensities and published sedimentary (GLOPIS-75) and cosmogenic (10Be and 36Cl) records. The Laschamp and Mono Lake excursions are clearly revealed by a very significant intensity drop at 41.2±1.6 ka and 34.2±1.2 ka respectively. The duration of the Laschamp excursion is ˜1500 yr and about 640 yr when the drop of paleointensity or the directional change are considered respectively. The intensity drop at the Mono Lake is twice as short. In the ˜7 ka interval separating the two excursions, the field intensity recovers to almost non-transitional values. The rate of decrease of the field intensity during these excursions attains 18 nT/yr for the Laschamp and even greater value (33 nT/yr) for the Mono Lake. This figure is, for the Laschamp excursion, similar to the present field intensity decrease in the last two centuries so that one may wonder whether such a high rate of change may be characteristic of an impending geomagnetic event (reversal or excursion). We suggest that the name Auckland excursion should be used for the present-day called Mono Lake.

  3. A record of bottom water temperature and seawater δ 18O for the Southern Ocean over the past 440 kyr based on Mg/Ca of benthic foraminiferal Uvigerina spp.

    NASA Astrophysics Data System (ADS)

    Elderfield, H.; Greaves, M.; Barker, S.; Hall, I. R.; Tripati, A.; Ferretti, P.; Crowhurst, S.; Booth, L.; Daunt, C.

    2010-01-01

    The sensitivity to temperature of Mg/Ca ratios in the shallow-infaunal benthic foraminifera Uvigerina spp. has been assessed. Core-top calibrations over ˜1-20 °C show a range in sensitivity of 0.065-0.084 mmol/mol/°C but few data are available spanning the temperature range anticipated in deep-sea records over glacial-interglacial cycles. In contrast to epibenthic foraminiferal species, carbonate ion saturation appears not to affect Mg/Ca significantly. A method based on estimating the ratio of the temperature sensitivity of foraminiferal Mg/Ca to that of δ 18O calcite shows that sensitivity for Mg/Ca at the high end of the observed core-top range (˜0.1 mmol/mol/°C) is required for consistency with LGM-Holocene differences in each property as constrained by independent proxy data. This is supported by a Mg/Ca record for Uvigerina spp. generated for the Southern Ocean over the past 440,000 years from Ocean Drilling Program Site 1123 (Chatham Rise, New Zealand). The record shows variability that correlates with climate oscillations. The LGM deep ocean temperature derived from the Mg/Ca record is -1.1 ± 0.3 °C. Transformation to temperature allows estimates to be made of changes in bottom water temperature and seawater δ 18O and comparison made with literature records. Analysis reveals a ˜2.5-kyr lead in the record of temperature over calcite δ 18O and a longer lead over seawater δ 18O. This is a reflection of larger phase offsets at eccentricity periods; phase offsets at tilt and precession are within error zero.

  4. Mutation particle swarm optimization of the BP-PID controller for piezoelectric ceramics

    NASA Astrophysics Data System (ADS)

    Zheng, Huaqing; Jiang, Minlan

    2016-01-01

    PID control is the most common used method in industrial control because its structure is simple and it is easy to implement. PID controller has good control effect, now it has been widely used. However, PID method has a few limitations. The overshoot of the PID controller is very big. The adjustment time is long. When the parameters of controlled plant are changing over time, the parameters of controller could hardly change automatically to adjust to changing environment. Thus, it can't meet the demand of control quality in the process of controlling piezoelectric ceramic. In order to effectively control the piezoelectric ceramic and improve the control accuracy, this paper replaced the learning algorithm of the BP with the mutation particle swarm optimization algorithm(MPSO) on the process of the parameters setting of BP-PID. That designed a better self-adaptive controller which is combing the BP neural network based on mutation particle swarm optimization with the conventional PID control theory. This combination is called the MPSO-BP-PID. In the mechanism of the MPSO, the mutation operation is carried out with the fitness variance and the global best fitness value as the standard. That can overcome the precocious of the PSO and strengthen its global search ability. As a result, the MPSO-BP-PID can complete controlling the controlled plant with higher speed and accuracy. Therefore, the MPSO-BP-PID is applied to the piezoelectric ceramic. It can effectively overcome the hysteresis, nonlinearity of the piezoelectric ceramic. In the experiment, compared with BP-PID and PSO-BP-PID, it proved that MPSO is effective and the MPSO-BP-PID has stronger adaptability and robustness.

  5. R7BP modulates opiate analgesia and tolerance but not withdrawal.

    PubMed

    Terzi, Dimitra; Cao, Yan; Agrimaki, Ioanna; Martemyanov, Kirill A; Zachariou, Venetia

    2012-03-01

    The adaptor protein R7 family binding protein (R7BP) modulates G protein coupled receptor (GPCR) signaling and desensitization by controlling the function of regulator of G protein signaling (RGS) proteins. R7BP is expressed throughout the brain and appears to modulate the membrane localization and stability of three proteins that belong to R7 RGS family: RGS6, RGS7, and RGS9-2. RGS9-2 is a potent negative modulator of opiate and psychostimulant addiction and promotes the development of analgesic tolerance to morphine, whereas the role of RGS6 and RGS7 in addiction remains unknown. Recent studies revealed that functional deletion of R7BP reduces R7 protein activity by preventing their anchoring to the cell membrane and enhances GPCR responsiveness in the basal ganglia. Here, we take advantage of R7BP knockout mice in order to examine the way interventions in R7 proteins function throughout the brain affect opiate actions. Our results suggest that R7BP is a negative modulator of the analgesic and locomotor activating actions of morphine. We also report that R7BP contributes to the development of morphine tolerance. Finally, our data suggest that although prevention of R7BP actions enhances the analgesic responses to morphine, it does not affect the severity of somatic withdrawal signs. Our data suggest that interventions in R7BP actions enhance the analgesic effect of morphine and prevent tolerance, without affecting withdrawal, pointing to R7BP complexes as potential new targets for analgesic drugs.

  6. Stress Granule Components G3BP1 and G3BP2 Play a Proviral Role Early in Chikungunya Virus Replication

    PubMed Central

    Scholte, Florine E. M.; Tas, Ali; Albulescu, Irina C.; Žusinaite, Eva; Merits, Andres; Snijder, Eric J.

    2015-01-01

    ABSTRACT Stress granules (SGs) are protein-mRNA aggregates that are formed in response to environmental stresses, resulting in translational inhibition. SGs are generally believed to play an antiviral role and are manipulated by many viruses, including various alphaviruses. GTPase-activating protein (SH3 domain)-binding protein 1 (G3BP1) is a key component and commonly used marker of SGs. Its homolog G3BP2 is a less extensively studied SG component. Here, we demonstrate that Chikungunya virus (CHIKV) infection induces cytoplasmic G3BP1- and G3BP2-containing granules that differ from bona fide SGs in terms of morphology, composition, and behavior. For several Old World alphaviruses it has been shown that nonstructural protein 3 (nsP3) interacts with G3BPs, presumably to inhibit SG formation, and we have confirmed this interaction in CHIKV-infected cells. Surprisingly, CHIKV also relied on G3BPs for efficient replication, as simultaneous depletion of G3BP1 and G3BP2 reduced viral RNA levels, CHIKV protein expression, and viral progeny titers. The G3BPs colocalized with CHIKV nsP2 and nsP3 in cytoplasmic foci, but no colocalization with nsP1, nsP4, or dsRNA was observed. Furthermore, G3BPs could not be detected in a cellular fraction enriched for CHIKV replication/transcription complexes, suggesting that they are not directly involved in CHIKV RNA synthesis. Depletion of G3BPs did not affect viral entry, translation of incoming genomes, or nonstructural polyprotein processing but resulted in severely reduced levels of negative-stranded (and consequently also positive-stranded) RNA. This suggests a role for the G3BPs in the switch from translation to genome amplification, although the exact mechanism by which they act remains to be explored. IMPORTANCE Chikungunya virus (CHIKV) causes a severe polyarthritis that has affected millions of people since its reemergence in 2004. The lack of approved vaccines or therapeutic options and the ongoing explosive outbreak in the

  7. Spatial climate dynamics in the Iberian Peninsula since 15 000 yr BP

    NASA Astrophysics Data System (ADS)

    Tarroso, Pedro; Carrión, José; Dorado-Valiño, Miriam; Queiroz, Paula; Santos, Luisa; Valdeolmillos-Rodríguez, Ana; Célio Alves, Paulo; Brito, José Carlos; Cheddadi, Rachid

    2016-05-01

    Climate changes in the Iberian Peninsula since the Last Glacial Maximum are associated with distributional shifts of major Mediterranean and European temperate species. The dynamic relationship between climate and species in the past may be retrieved from the fossil records available in the Iberian Peninsula. We have used an extensive set of pollen records to reconstruct spatial layers (1 kyr interval) of January minimum temperature, July maximum temperature, and annual precipitation over the time period between 15 and 3 ka. A functional principal component analysis was used to summarise the spatial evolution of climate in areas that share similar climate trends. When compared between them, the identified four areas show different climate trends over the studied period and are coherent with the existence of multiple refugial areas within the Iberian Peninsula.

  8. Genetic and Morphological Features of Human iPSC-Derived Neurons with Chromosome 15q11.2 (BP1-BP2) Deletions

    PubMed Central

    Das, Dhanjit K.; Tapias, Victor; D'Aiuto, Leonardo; Chowdari, Kodavali V.; Francis, Lily; Zhi, Yun; Ghosh, Ayantika; Surti, Urvashi; Tischfield, Jay; Sheldon, Michael; Moore, Jennifer C.; Fish, Ken; Nimgaonkar, Vishwajit L.

    2015-01-01

    Background Copy number variation on chromosome 15q11.2 (BP1-BP2) causes a deletion of CYFIP1, NIPA1, NIPA2 and TUBGCP5. Furthermore, it also affects brain structure and elevates the risk for several neurodevelopmental disorders that are associated with dendritic spine abnormalities. In rodents, altered cyfip1 expression changes dendritic spine morphology, motivating analyses of human neuronal cells derived from induced pluripotent stem cells (iPSCs; iPSC-neurons). Methods iPSCs were generated from a mother and her offspring, both carrying the 15q11.2 (BP1-BP2) deletion, and a non-deletion control. Gene expression in the deletion region was estimated using quantitative real-time PCR assays. Neural progenitor cells (NPCs) and iPSC-neurons were characterized using immunocytochemistry. Results CYFIP1, NIPA1, NIPA2 and TUBGCP5 gene expression was lower in iPSCs, NPCs and iPSC-neurons from the mother and her offspring in relation to control cells. CYFIP1 and PSD-95 protein levels were lower in iPSC-neurons derived from the copy number variant-bearing individuals using Western blot analysis. Ten weeks after differentiation, iPSC-neurons appeared to show dendritic spines, and qualitative analysis suggested that dendritic morphology was altered in 15q11.2-deletion subjects compared with control cells. Conclusions The 15q11.2 (BP1-BP2) deletion is associated with a reduced expression of four genes in iPSC-derived neuronal cells; it may also be associated with altered iPSC-neuron dendritic morphology. PMID:26528485

  9. Geoarchaeological evidence from Peru for a 5000 years B.P. onset of El Nino

    SciTech Connect

    Sandweiss, D.H.; Richardson, J.B. III; Rollins, H.B.

    1996-09-13

    For the tropical west coast of South America, where El Nino/Southern Oscillation (ENSO) is most pronounced, archaeological and associated paleontological deposits in northern Peru revealed a major climate change at about 5000 years before the present (yr B.P.). The data implied the presence of stable, warm tropical water as far south as 10{degrees}S during the early mid-Holocene (about 8000 to 5000 yr B.P.). These data suggest that ENSO did not occur for some millennia preceding 5000 yr B.P., when global and regional climate was warmer than today. 36 refs., 1 fig., 3 tabs.

  10. Two Isoforms of the RNA Binding Protein, Coding Region Determinant-binding Protein (CRD-BP/IGF2BP1), Are Expressed in Breast Epithelium and Support Clonogenic Growth of Breast Tumor Cells.

    PubMed

    Fakhraldeen, Saja A; Clark, Rod J; Roopra, Avtar; Chin, Emily N; Huang, Wei; Castorino, John; Wisinski, Kari B; Kim, TaeWon; Spiegelman, Vladimir S; Alexander, Caroline M

    2015-05-22

    CRD-BP/IGF2BP1 has been characterized as an "oncofetal" RNA binding protein typically highly expressed in embryonic tissues, suppressed in normal adult tissues, but induced in many tumor types. In this study, we show that adult breast tissues express ubiquitous but low levels of CRD-BP protein and mRNA. Although CRD-BP mRNA expression is induced in breast tumor cells, levels remain ∼1000-fold lower than in embryonic tissues. Despite low expression levels, CRD-BP is required for clonogenic growth of breast cancer cells. We reveal that because the most common protein isoform in normal adult breast and breast tumors has an N-terminal deletion (lacking two RNA recognition motif (RRM) domains) and is therefore missing antibody epitopes, CRD-BP expression has been under-reported by previous studies. We show that a CRD-BP mutant mouse strain retains expression of the shorter transcript (ΔN-CRD-BP), which originates in intron 2, suggesting that the impact of complete ablation of this gene in mice is not yet known. Either the full-length CRD-BP or the N-terminally truncated version can rescue the clonogenicity of CRD-BP knockdown breast cancer cells, suggesting that clonogenic function is served by either CRD-BP isoform. In summary, although CRD-BP expression levels are low in breast cancer cells, this protein is necessary for clonogenic activity.

  11. Clinical and Immunological Studies of 332 Japanese Patients Tentatively Diagnosed as Anti-BP180-type Mucous Membrane Pemphigoid: A Novel BP180 C-terminal Domain Enzyme-linked Immunosorbent Assay.

    PubMed

    Yasukochi, Atsushi; Teye, Kwesi; Ishii, Norito; Hashimoto, Takashi

    2016-08-23

    Diagnosis of anti-BP180-type mucous membrane pemphigoid (BP180-MMP) is frustrated by the difficulty of detecting BP180 reactivity. A total of 721 patients with suspected MMP, selected from a cohort of 4,698 patients with autoimmune bullous disease (AIBD), were included in this study. Of these, 332 patients were tentatively diagnosed as BP180-MMP if they showed IgG/IgA reactivity with the epidermal side of 1M NaCl-split-skin and/or positive reactivity with BP180 in at least one of our antigen detection methods. Clinically, a predominance of female patients was found. Oral mucosal and cutaneous lesions were found in 85.5% and 41.0% of patients, respectively, and frequent treatments were systemic steroids, tetracycline/minocycline and diaminodiphenyl sulfone. Various immunological methods, including a newly developed BP180 C-terminal domain enzyme-linked immunosorbent assay (ELISA), revealed frequent reactivity with BP180 C-terminal and NC16a domains. Some patients reacted with BP180 and other antigens, indicating that BP180-MMP tends to concur with other AIBDs. This large study of patients with suspected BP180-MMP indicates the difficulty of diagnosis of BP180-MMP and the diagnostic usefulness of BP180 C-terminal domain ELISA.

  12. Conduit Magma Storage during the 800 BP Quilotoa Eruption, Ecuador

    NASA Astrophysics Data System (ADS)

    Ort, M. H.; Cashman, K. V.; Di Muro, A.; Best, J. A.; Rosi, M.; Mothes, P. A.; Bustillos, J.

    2013-12-01

    The 800 BP eruption of Quilotoa produced two large ignimbrites, U1 (~5.8 km3 DRE) and U3 (~1.8 km3 DRE). These eruptions were separated by a series of much smaller eruptions over one to several weeks, as inferred from 1) the intercalation of secondary pyroclastic and debris flow deposits between U1 and U3, 2) deposits from phreatic explosions from the U1 ignimbrite surface, 3) oxidation of the upper 2 m of U1, and 4) a lack of erosion of the U1 surface. Why did the main phase of the eruption (U1) stall when eruptable magma was available? How did explosive activity stop and restart? We address these questions by examining deposits (U2) emplaced during the 'hiatus' that provide information on the conditions in the conduit and vent area between explosive episodes. The lowest sub-unit, U2a, forms a series of pumiceous surge deposits found only within 5 km of the crater rim. U2b is a vitric-poor, crystal- and lithic-rich fall deposit distributed to about 15 km from the crater. U2c is a thin gray fine ash containing 2-5-mm-diameter rhyolite lapilli that is present within 6 km of the vent. Similar lapilli also occur in the lowermost few centimeters of U3 and appear to be from a dome that exploded as the new magma arrived at the surface; their presence as small ballistic fragments ties U2c to lowermost U3 in time. U2a appears to have been emplaced by episodic surges and weak fallout plumes, whereas U2b and U2c were deposited from a series of sustained eruption columns. Moreover, the lack of U2b grain-size variation with distance suggests that the grain size was determined at the vent, not by transport. FTIR analysis of CO2 and H2O in melt inclusions (MIs) indicates that a deep magma chamber (>400 MPa; ~12 km) fed U1. U2a and U2b MIs plot along vapor isopleths, suggesting equilibration at pressures to about 300 MPa as CO2 outgassed. U2b MIs have lower CO2 than U2a, perhaps indicating continued degassing during the 'hiatus'. MIs from the lower few centimeters of U3 lie along

  13. Differential scattering cross sections for collisions of 0.5-, 1.5-, and 5.0-keV helium atoms with He, H2, N2, and O2. [for atmospheric processes modeling

    NASA Technical Reports Server (NTRS)

    Newman, J. H.; Smith, K. A.; Stebbings, R. F.; Chen, Y. S.

    1985-01-01

    This paper reports the first results of an experimental program established to provide cross section data for use in modeling various atmospheric processes. Absolute cross sections, differential in the scattering angle, have been measured for collisions of 0.5-, 1.5-, and 5.0-keV helium atoms with He, H2, N2, and O2 at laboratory scattering angles between 0.1 deg and 5 deg. The results are the sums of cross sections for elastic and inelastic scattering of helium atoms; charged collision products are not detected. Integration of the differential cross section data yields integral cross sections consistent with measurements by other workers. The apparatus employs a position-sensitive detector for both primary and scattered particles and uses a short target cell with a large exit aperture to ensure a simple and well-defined apparatus geometry.

  14. Magnetization reversal properties of Pr{sub 1-x}(Gd/Nd){sub x}MnO{sub 3} (x=0.3, 0.5, 0.7)

    SciTech Connect

    Biswas, Sanjay; Pal, Sudipta; Bose, Esa

    2015-06-24

    We report measurements of the temperature dependent magnetic properties of single phase orthorhombic perovskites system associated with space group Pbnm compounds Pr{sub 1-x}(Gd/Nd){sub x}MnO{sub 3} (x=0.3, 0.5, 0.7). Magnetic properties radically changes with the doping of Gd or Nd. A magnetization reversal is observed below the Neel temperature (T{sub N}), in DC magnetization measurements (at 50 Oe) in the doped compounds. The reversal of magnetization may be due to the antiparallel coupling between the two magnetic sublattices (|Pr+ Gd/ Nd | and Mn). The hysteresis plot taken at 50K indicates a ferrimagnetic characteristic and existence of spin canting of ions in the magnetic sublattices.

  15. Enhancement of spin polarization via Fermi level tuning in Co{sub 2}MnSn{sub 1−x}Sb{sub x} (x = 0, 0.25. 0.5, 0.75, 1) Heusler alloys

    SciTech Connect

    Singh, Mukhtiyar Thakur, Jyoti; Kashyap, Manish K.; Saini, Hardev S.

    2014-04-24

    Full potential approach has been employed to tune Fermi level in Co{sub 2}MnSn{sub 1−x}Sb{sub x} (x = 0, 0.25, 0.5, 0.75, 1) Heulser alloys for enhancement of spin polarization and finding signature of half metallicity. Present density functional theory (DFT) based calculation indicates that stoichoimetric Heusler alloy, Co{sub 2}MnSn is not a half-metallic ferromagnet but the doping of Sb in it results in the shifting of E{sup F} in well-defined energy gap which leads the 100% spin polarization in the resultant alloys. The magnetism in present alloys is governed by localized moment on Mn atom mainly. The tuning of half-metallicity using doping can be proved as an ideal technique to search the new materials which can accomplish the need of spintronics.

  16. First principles study of three dimensional topological phases of GdxY1-xPtBi (x=0, 0.25, 0.5, 0.75, 1) alloys

    NASA Astrophysics Data System (ADS)

    Nourbakhsh, Z.; Faizi-Mohazzab, B.

    2015-12-01

    The structural, electronic and magnetic properties and existence of topological phase of GdxY1-xPtBi (x=0, 0.25, 0.5, 0.75, 1) alloys are studied using density functional theory. The lattice constant and bulk modulus of these alloys in ferromagnetic phase are calculated using the generalized gradient approximation (GGA) in the presence of spin-orbit coupling. To investigate the electronic properties and existence of topological phase, the local density approximation (LDA), GGA and Engel-Vosko generalized gradient approximation (EV-GGA) are used. The electron density of states, band structure and topological band order of these alloys are investigated. Furthermore the variations of magnetic momentum, the linear coefficient of electronic specific heat and the band inversion strength with increase of x are investigated.

  17. REPTOR and REPTOR-BP regulate organismal metabolism and transcription downstream of TORC1

    PubMed Central

    Tiebe, Marcel; Lutz, Marilena; De La Garza, Adriana; Buechling, Tina; Boutros, Michael; Teleman, Aurelio A.

    2015-01-01

    SUMMARY TORC1 regulates growth and metabolism in part by influencing transcriptional programs. We identify here REPTOR and REPTOR-BP as transcription factors downstream of TORC1, required for ~90% of the transcriptional induction that occurs upon TORC1 inhibition in Drosophila. Thus REPTOR and REPTOR-BP are major effectors of the transcriptional stress response induced upon TORC1 inhibition, analogous to the role of FOXO downstream of Akt. We find that when TORC1 is active, it phosphorylates REPTOR on Ser527 and Ser530, leading to REPTOR cytoplasmic retention. Upon TORC1 inhibition, REPTOR becomes dephosphorylated in a PP2A dependent manner, shuttles into the nucleus, joins its partner REPTOR-BP to bind target genes, and activates their transcription. In vivo functional analysis using knockout flies reveals that REPTOR and REPTOR-BP play critical roles in maintaining energy homeostasis and promoting animal survival upon nutrient restriction. PMID:25920570

  18. Environmental Conditions in northern Gulf of Mexico Estuaries: before and after the BP Oil Spill

    EPA Science Inventory

    This presentation provides a summary of ecological condition and sediment chemistry data for northern Gulf of Mexico estuaries that were exposed to oil and oil-related contaminants from the BP Oil Spill.

  19. 1. ENVIRONMENT, FROM NORTHWEST, SHOWING B&P INTERLOCKING TOWER AND POWER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. ENVIRONMENT, FROM NORTHWEST, SHOWING B&P INTERLOCKING TOWER AND POWER SUBSTATIONS - Baltimore & Potomac Interlocking Tower, Adjacent to AMTRAK railroad tracks in block bounded by Howard Street, Jones Falls Expressway, Maryland Avenue & Falls Road, Baltimore, Independent City, MD

  20. 53BP1 regulates DSB repair using Rif1 to control 5' end resection.

    PubMed

    Zimmermann, Michal; Lottersberger, Francisca; Buonomo, Sara B; Sfeir, Agnel; de Lange, Titia

    2013-02-08

    The choice between double-strand break (DSB) repair by either homology-directed repair (HDR) or nonhomologous end joining (NHEJ) is tightly regulated. Defects in this regulation can induce genome instability and cancer. 53BP1 is critical for the control of DSB repair, promoting NHEJ, and inhibiting the 5' end resection needed for HDR. Using dysfunctional telomeres and genome-wide DSBs, we identify Rif1 as the main factor used by 53BP1 to impair 5' end resection. Rif1 inhibits resection involving CtIP, BLM, and Exo1; limits accumulation of BRCA1/BARD1 complexes at sites of DNA damage; and defines one of the mechanisms by which 53BP1 causes chromosomal abnormalities in Brca1-deficient cells. These data establish Rif1 as an important contributor to the control of DSB repair by 53BP1.

  1. Synthetic Minor NSR Permit: BP America Production Company - Salvador I/II Central Delivery Point

    EPA Pesticide Factsheets

    This page contains the final synthetic minor NSR permit for the BP America Production Company, Salvador I/II Central Delivery Point, located on the Southern Ute Indian Reservation in La Plata County, CO.

  2. ERK1/2 is dephosphorylated by a novel phosphatase--CacyBP/SIP.

    PubMed

    Kilanczyk, Ewa; Filipek, Slawomir; Filipek, Anna

    2011-01-07

    Recently, we have reported that the CacyBP/SIP protein binds ERK1/2 (Kilanczyk et al., BBRC, 2009). In this work we show that CacyBP/SIP exhibits a phosphatase activity toward ERK1/2 kinases while its E217K mutant does not. The K(m) and V(max) values established for a standard phosphatase substrate, p-NPP, are 16.9±3.6 mM and 4.3±0.4 μmol/min, respectively. The CacyBP/SIP phosphatase activity is decreased by okadaic acid (IC(50)=45 nM). Our experimental results are supported by a theoretical analysis which revealed important sequence similarities between CacyBP/SIP and the phosphatase-like proteins as well as certain MAP kinase phosphatases.

  3. Synthetic Minor NSR Permit: BP America Production Company - Wolf Point Central Delivery Point

    EPA Pesticide Factsheets

    This page contains the response to public comments and the final synthetic minor NSR permit for the BP America Production Company, Wolf Point Central Delivery Point, located on the Southern Ute Indian Reservation in La Plata County, CO.

  4. Synthetic Minor NSR Permit: BP America Production Company - Treating Site #8 Central Delivery Point

    EPA Pesticide Factsheets

    This page contains the response to public comments and the final synthetic minor NSR permit for the BP America Production Company, Treating Site #8 Central Delivery Point, located on the Southern Ute Indian Reservation in La Plata County, CO.

  5. Characterization of a birch (Betula pendula Roth.) embryogenic gene, BP8.

    PubMed

    Puupponen-Pimiä, R; Saloheimo, M; Vasara, T; Ra, R; Gaugecz, J; Kurtén, U; Knowles, J K; Keränen, S; Kauppinen, V

    1993-10-01

    We have isolated the birch homologue (BP8) for the carrot embryogenic gene DC8 by heterologous hybridization. The birch BP8 gene encodes a putative protein of 53 kDa, showing 52% sequence identity with the DC8 gene at the amino acid level. The putative BP8 protein contains 20 repeats of 11 amino acids and thus belongs to the group of LEA proteins isolated from such plants as carrot, cotton and wheat. Northern hybridization of mRNA isolated from birch cells representing different stages of somatic embryogenesis and non-embryogenetic material with a PB8 probe gave no signals, suggesting a low expression level of the BP8 gene.

  6. Molecular Environments of Three Large Supernova Remnants in the Third Galactic Quadrant: G205.5+0.5, G206.9+2.3, and G213.0–0.6

    NASA Astrophysics Data System (ADS)

    Su, Yang; Zhou, Xin; Yang, Ji; Chen, Xuepeng; Chen, Yang; Liu, Yi; Wang, Hongchi; Li, Chong; Zhang, Shaobo

    2017-02-01

    We present CO observations toward three large supernova remnants (SNRs) in the third Galactic quadrant using the Purple Mountain Observatory Delingha 13.7 m millimeter-wavelength telescope. The observations are part of the high-resolution CO survey of the Galactic plane between Galactic longitudes l=-10^\\circ to 250^\\circ and latitudes b=-5^\\circ to 5^\\circ . CO emission was detected toward the three SNRs: G205.5+0.5 (Monoceros Nebula), G206.9+2.3 (PKS 0646+06), and G213.0–0.6. Both SNRs G205.5+0.5 and G213.0–0.6 exhibit the morphological agreement (or spatial correspondences) between the remnant and the surrounding molecular clouds (MCs), as well as kinematic signatures of shock perturbation in the molecular gas. We confirm that the two SNRs are physically associated with their ambient MCs and the shock of SNRs is interacting with the dense, clumpy molecular gas. SNR G206.9+2.3, which is close to the northeastern edge of the Monoceros Nebula, displays the spatial coincidence with molecular partial shell structures at V LSR ∼ 15 km s‑1. While no significant line broadening has been detected within or near the remnant, the strong morphological correspondence between the SNR and the molecular cavity implies that SNR G206.9+2.3 is probably associated with the CO gas and is evolving in the low-density environment. The physical features of individual SNRs, together with the relationship between SNRs and their nearby objects, are also discussed.

  7. Role of the CacyBP/SIP protein in gastric cancer.

    PubMed

    Zhai, Huihong; Meng, Juan; Jin, Haifeng; Li, Yuanfei; Wang, Jinbo

    2015-05-01

    Various reports indicate that calcyclin binding protein/Siah-1-interacting protein (CacyBP/SIP) is an important protein in tumorigenesis, but whether CacyBP/SIP promotes or suppresses cancer may depend on the cell type. In order to investigate whether CacyBP/SIP is significant in gastric cancerous tumorigenesis, the present study used immunohistochemistry to analyze 181 gastric cancer tissue samples, as well as 181 healthy tissue samples from the same gastric cancer patients. The immunohistochemical results were compared against patient data and pathological analysis of the tissue slices, including gender, age, degree of tumor differentiation and tumor, node, metastasis (TNM) stage. In addition, the level of CacyBP/SIP expression was detected in three frozen tissue samples of gastric adenocarcinoma using western blot analysis. Of the 181 cases analyzed in the present study, 80 cases were identified as non-metastatic gastric cancer and 101 cases were identified as gastric cancer that had metastasized to the lymph nodes. Tissue biopsies from the two sets of patients were examined using immunohistochemistry to identify the level of CacyBP/SIP expression in metastatic and primary gastric cancer tissues. Statistical analyses were performed on all data. The immunohistochemical analysis revealed that CacyBP/SIP was expressed in 31% (56/181) of gastric adenocarcinoma tissue samples and 7% (12/181) of adjacent non-cancerous gastric tissues (P<0.05). Furthermore, the expression levels of CacyBP/SIP were higher in cancerous tissue compared with the adjacent non-cancerous gastric tissue using western blotting. No association was identified between CacyBP/SIP expression and patient age (P=0.975), gender (P=0.185), degree of tumor differentiation (P=0.076) or TNM stage (P=0.979). Among the 101 patients with metastatic gastric cancer, CacyBP/SIP was expressed at primary sites in 31% (31/101) of cases and at metastatic sites in 26% (26/101) of cases (P=0.434). However, among the

  8. Cherubism Gene Sh3bp2 is Important for Optimal Bone Formation, Osteoblast Differentiation and Function

    PubMed Central

    Mukherjee, Padma M.; Wang, Chiachien J.; Chen, I-Ping; Jafarov, Toghrul; Olsen, Bjorn R.; Ueki, Yasuyoshi; Reichenberger, Ernst J.

    2012-01-01

    Introduction Cherubism is a human genetic disorder that causes bilateral symmetrical enlargement of the maxilla and mandible in children. It is caused by mutations in SH3BP2. The exact pathogenesis of the disorder is an area of active research. Sh3bp2 knock-in mice were developed by introducing a Pro416Arg mutation (Pro418Arg in humans) in the mouse genome. The osteoclast phenotype of this mouse model was recently described. Methods We examined the bone phenotype of the cherubism mouse model, the role of Sh3bp2 during bone formation, osteoblast differentiation and osteoblast function. Results We observed delays in early postnatal development of homozygous Sh3bp2KI/KI mice. Sh3bp2KI/KI mice exhibit increased growth plate thickness and significantly decreased trabecular bone thickness and reduced bone mineral density. Histomorphometric and μ-CT analyses reveal bone loss in cranial and appendicular skeleton. Sh3bp2KI/KI mice also exhibit a significant decrease in osteoid formation that indicates a defect in osteoblast function. Calvarial osteoblast cell cultures exhibit a decrease in alkaline phosphatase expression and mineralization suggesting reduced differentiation potential. Gene expression of osteoblast differentiation markers like collagen type-I, alkaline phosphatase and osteocalcin are decreased in osteoblast cultures from Sh3bp2KI/KI mice. Conclusions These data suggest that Sh3bp2 function regulates bone homeostasis not only through osteoclast-specific effects but also through effects on osteoblast differentiation and function. PMID:20691350

  9. Heterostructured hBN-BP-hBN Nanodetectors at Terahertz Frequencies.

    PubMed

    Viti, Leonardo; Hu, Jin; Coquillat, Dominique; Politano, Antonio; Consejo, Christophe; Knap, Wojciech; Vitiello, Miriam S

    2016-09-01

    By reassembling thin isolated atomic planes of hexagonal borum nitride (hBN) with a few layer phosphorene black phosphorus (BP), hBN/BP/hBN heterostructures are mechanically stacked to devise high-efficiency THz photodetectors operating in the 0.3-0.65 THz range, from 4 K to 300 K, with a record signal-to-noise ratio of 20 000.

  10. RNA-binding protein IGF2BP3 targeting of oncogenic transcripts promotes hematopoietic progenitor proliferation

    PubMed Central

    Palanichamy, Jayanth Kumar; Tran, Tiffany M.; Howard, Jonathan M.; Contreras, Jorge R.; Fernando, Thilini R.; Sterne-Weiler, Timothy; Katzman, Sol; Toloue, Masoud; Yan, Weihong; Sanford, Jeremy R.; Rao, Dinesh S.

    2016-01-01

    Posttranscriptional control of gene expression is important for defining both normal and pathological cellular phenotypes. In vitro, RNA-binding proteins (RBPs) have recently been shown to play important roles in posttranscriptional regulation; however, the contribution of RBPs to cell specification is not well understood. Here, we determined that the RBP insulin-like growth factor 2 mRNA-binding protein 3 (IGF2BP3) is specifically overexpressed in mixed lineage leukemia–rearranged (MLL-rearranged) B-acute lymphoblastic leukemia (B-ALL), which constitutes a subtype of this malignancy associated with poor prognosis and high risk of relapse. IGF2BP3 was required for the survival of B-ALL cell lines, as knockdown led to decreased proliferation and increased apoptosis. Enforced expression of IGF2BP3 provided murine BM cells with a strong survival advantage, led to proliferation of hematopoietic stem and progenitor cells, and skewed hematopoietic development to the B cell/myeloid lineage. Cross-link immunoprecipitation and high throughput sequencing uncovered the IGF2BP3-regulated transcriptome, which includes oncogenes MYC and CDK6 as direct targets. IGF2BP3 regulated transcripts via targeting elements within 3′ untranslated regions (3′UTR), and enforced IGF2BP3 expression in mice resulted in enhanced expression of Myc and Cdk6 in BM. Together, our data suggest that IGF2BP3-mediated targeting of oncogenic transcripts may represent a critical pathogenetic mechanism in MLL-rearranged B-ALL and support IGF2BP3 and its cognate RNA-binding partners as potential therapeutic targets in this disease. PMID:26974154

  11. BP control and left ventricular hypertrophy regression in children with CKD.

    PubMed

    Kupferman, Juan C; Aronson Friedman, Lisa; Cox, Christopher; Flynn, Joseph; Furth, Susan; Warady, Bradley; Mitsnefes, Mark

    2014-01-01

    In adult patients with CKD, hypertension is linked to the development of left ventricular hypertrophy, but whether this association exists in children with CKD has not been determined conclusively. To assess the relationship between BP and left ventricular hypertrophy, we prospectively analyzed data from the Chronic Kidney Disease in Children cohort. In total, 478 subjects were enrolled, and 435, 321, and 142 subjects remained enrolled at years 1, 3, and 5, respectively. Echocardiograms were obtained 1 year after study entry and then every 2 years; BP was measured annually. A linear mixed model was used to assess the effect of BP on left ventricular mass index, which was measured at three different visits, and a mixed logistic model was used to assess left ventricular hypertrophy. These models were part of a joint longitudinal and survival model to adjust for informative dropout. Predictors of left ventricular mass index included systolic BP, anemia, and use of antihypertensive medications other than angiotensin-converting enzyme inhibitors or angiotensin receptor blockers. Predictors of left ventricular hypertrophy included systolic BP, female sex, anemia, and use of other antihypertensive medications. Over 4 years, the adjusted prevalence of left ventricular hypertrophy decreased from 15.3% to 12.6% in a systolic BP model and from 15.1% to 12.6% in a diastolic BP model. These results indicate that a decline in BP may predict a decline in left ventricular hypertrophy in children with CKD and suggest additional factors that warrant additional investigation as predictors of left ventricular hypertrophy in these patients.

  12. Discrete Sampling Test Plan for the 200-BP-5 Operable Unit

    SciTech Connect

    Sweeney, Mark D.

    2010-02-04

    The Discrete Groundwater Sampling Project is conducted by the Pacific Northwest National Laboratory (PNNL) on behalf of CH2M HILL Plateau Remediation Company. The project is focused on delivering groundwater samples from proscribed horizons within select groundwater wells residing in the 200-BP-5 Operable Unit (200-BP-5 OU) on the Hanford Site. This document provides the scope, schedule, methodology, and other details of the PNNL discrete sampling effort.

  13. RNA-binding protein IGF2BP3 targeting of oncogenic transcripts promotes hematopoietic progenitor proliferation.

    PubMed

    Palanichamy, Jayanth Kumar; Tran, Tiffany M; Howard, Jonathan M; Contreras, Jorge R; Fernando, Thilini R; Sterne-Weiler, Timothy; Katzman, Sol; Toloue, Masoud; Yan, Weihong; Basso, Giuseppe; Pigazzi, Martina; Sanford, Jeremy R; Rao, Dinesh S

    2016-04-01

    Posttranscriptional control of gene expression is important for defining both normal and pathological cellular phenotypes. In vitro, RNA-binding proteins (RBPs) have recently been shown to play important roles in posttranscriptional regulation; however, the contribution of RBPs to cell specification is not well understood. Here, we determined that the RBP insulin-like growth factor 2 mRNA-binding protein 3 (IGF2BP3) is specifically overexpressed in mixed lineage leukemia-rearranged (MLL-rearranged) B-acute lymphoblastic leukemia (B-ALL), which constitutes a subtype of this malignancy associated with poor prognosis and high risk of relapse. IGF2BP3 was required for the survival of B-ALL cell lines, as knockdown led to decreased proliferation and increased apoptosis. Enforced expression of IGF2BP3 provided murine BM cells with a strong survival advantage, led to proliferation of hematopoietic stem and progenitor cells, and skewed hematopoietic development to the B cell/myeloid lineage. Cross-link immunoprecipitation and high throughput sequencing uncovered the IGF2BP3-regulated transcriptome, which includes oncogenes MYC and CDK6 as direct targets. IGF2BP3 regulated transcripts via targeting elements within 3' untranslated regions (3'UTR), and enforced IGF2BP3 expression in mice resulted in enhanced expression of Myc and Cdk6 in BM. Together, our data suggest that IGF2BP3-mediated targeting of oncogenic transcripts may represent a critical pathogenetic mechanism in MLL-rearranged B-ALL and support IGF2BP3 and its cognate RNA-binding partners as potential therapeutic targets in this disease.

  14. 53BP1 fosters fidelity of homology-directed DNA repair.

    PubMed

    Ochs, Fena; Somyajit, Kumar; Altmeyer, Matthias; Rask, Maj-Britt; Lukas, Jiri; Lukas, Claudia

    2016-08-01

    Repair of DNA double-strand breaks (DSBs) in mammals is coordinated by the ubiquitin-dependent accumulation of 53BP1 at DSB-flanking chromatin. Owing to its ability to limit DNA-end processing, 53BP1 is thought to promote nonhomologous end-joining (NHEJ) and to suppress homology-directed repair (HDR). Here, we show that silencing 53BP1 or exhausting its capacity to bind damaged chromatin changes limited DSB resection to hyper-resection and results in a switch from error-free gene conversion by RAD51 to mutagenic single-strand annealing by RAD52. Thus, rather than suppressing HDR, 53BP1 fosters its fidelity. These findings illuminate causes and consequences of synthetic viability acquired through 53BP1 silencing in cells lacking the BRCA1 tumor suppressor. We show that such cells survive DSB assaults at the cost of increasing reliance on RAD52-mediated HDR, which may fuel genome instability. However, our findings suggest that when challenged by DSBs, BRCA1- and 53BP1-deficient cells may become hypersensitive to, and be eliminated by, RAD52 inhibition.

  15. Mind Bomb-Binding Partner RanBP9 Plays a Contributory Role in Retinal Development.

    PubMed

    Yoo, Kyeong-Won; Thiruvarangan, Maivannan; Jeong, Yun-Mi; Lee, Mi-Sun; Maddirevula, Sateesh; Rhee, Myungchull; Bae, Young-Ki; Kim, Hyung-Goo; Kim, Cheol-Hee

    2017-03-28

    Ran-binding protein family member, RanBP9 has been reported in various basic cellular mechanisms and neuropathological conditions including schizophrenia. Previous studies have reported that RanBP9 is highly expressed in the mammalian brain and retina; however, the role of RanBP9 in retinal development is largely unknown. Here, we present the novel and regulatory roles of RanBP9 in retinal development of a vertebrate animal model, zebrafish. Zebrafish embryos exhibited abundant expression of ranbp9 in developing brain tissues as well as in the developing retina. Yeast two-hybrid screening demonstrated the interaction of RanBP9 with Mind bomb, a component of Notch signaling involved in both neurogenesis and neural disease autism. The interaction is further substantiated by co-localization studies in cultured cells. Knockdown of ranbp9 resulted in retinal dysplasia with defective proliferation of retinal cells, downregulation of neuronal differentiation marker huC, elevation of neural proliferation marker her4, and alteration of cell cycle marker p57kip2. Expression of the Müller glial cell marker glutamine synthase was also affected in knockdown morphants. Our results suggest that Mind bombbinding partner RanBP9 plays a role during retinal cell development of zebrafish embryogenesis.

  16. The preparation of BP single crystals by high pressure flux method

    NASA Technical Reports Server (NTRS)

    Kumashiro, Y.; Misawa, S.; Gonda, S.

    1984-01-01

    Single crystals of BP, a III-V compound semiconductor, were obtained by the high pressure flux method. Cu3P and Ni12P5 powders were used as the flux, and mixed with BP powder. Two kinds of mixtures were prepared: (1) 1.8g (BP) + 35 G (Cu3P) and (2) 1.7 g (BP) + 25 g (Ni12P5). They were compressed into pellets, heated at 1300 C for 24 h in an induction furnace under a pressure of 1 MPa using Ar-P2 gas, and slowly cooled to room temperature. In case (1), BP single crystals grew along the (III) plane, and in case (2) they grew as an aggregate of crystallites. The cathodoluminescence spectra of the synthetic BP crystals showed peaks near 680 nm (1.82 eV) for case (1), and 500 nm (2.47 eV) for case (2). By using the high pressure flux method conventional sized crystals were obtained in a relatively short time.

  17. Effects of BP-14, a novel cyclin-dependent kinase inhibitor, on anaplastic thyroid cancer cells.

    PubMed

    Allegri, Lorenzo; Baldan, Federica; Mio, Catia; Puppin, Cinzia; Russo, Diego; Kryštof, Vladimir; Damante, Giuseppe

    2016-04-01

    Anaplastic thyroid carcinoma (ATC) is an extremely aggressive human malignancy characterized by a marked degree of invasiveness, absense of features of thyroid differentiation and resistance to current medical treatment. It is well known that ATCs are characterized by deregulation of genes related to cell cycle regulation, i.e., cyclin-dependent kinases (CDKs) and endogenous cyclin-dependent kinase inhibitors (CDKIs). Therefore, in the present study, the effect of a novel exogenous cyclin-dependent kinase inhibitor, BP-14, was investigated in three human ATC cell lines. The ATC-derived cell lines FRO, SW1736 and 8505C were treated with BP-14 alone or in combination with the mTOR inhibitor everolimus. In all ATC cell lines, treatment with BP-14 decreased cell viability and, in two of them, BP-14 modified expression of genes involved in epithelial-mesenchymal transition. Thus, our data indicate that BP-14 is a potential new compound effective against ATC. Combined treatment with BP-14 and the mTOR inhibitor everolimus had a strong synergistic effect on cell viability in all three cell lines, suggesting that the combined used of CDK and mTOR inhibitors may be a useful strategy for ATC treatment.

  18. Asian-specific mitochondrial genome polymorphism (9-bp deletion) in Hungarian patients with mitochondrial disease.

    PubMed

    Pentelenyi, Klara; Remenyi, Viktoria; Gal, Aniko; Milley, Gyorgy Mate; Csosz, Aranka; Mende, Balazs Gusztav; Molnar, Maria Judit

    2016-05-01

    A 9-bp deletion of the mtDNA is known as an anthropological marker of people with East-Asian origin. This 9-bp mtDNA deletion was analyzed in 1073 Hungarians with suspected mitochondrial disease and in 468 healthy control individuals. Fourteen cases with the 9-bp deletion were found in the cohort of mitochondrial patients, and one individual from 468 controls. In six cases the 9-bp deletion was present together with pathogenic major deletions in the mitochondrial genome. In one patient we found a frame shift mutation in the D-loop region, and in another family a pathogenic m.8322 A > G mutation in the tRNA(Lys) gene. Although the 9-bp deletion is common in the populations of the Pacific region and Asia, it is present in the Hungarian population as well. This 9-bp deletion may induce instability of the mtDNA and may provoke the introduction of other pathogenic mutations.

  19. CtBP1 associates metabolic syndrome and breast carcinogenesis targeting multiple miRNAs

    PubMed Central

    De Luca, Paola; Dalton, Guillermo N.; Scalise, Georgina D.; Moiola, Cristian P.; Porretti, Juliana; Massillo, Cintia; Kordon, Edith; Gardner, Kevin; Zalazar, Florencia; Flumian, Carolina; Todaro, Laura; Vazquez, Elba S.; Meiss, Roberto; De Siervi, Adriana

    2016-01-01

    Metabolic syndrome (MeS) has been identified as a risk factor for breast cancer. C-terminal binding protein 1 (CtBP1) is a co-repressor of tumor suppressor genes that is activated by low NAD+/NADH ratio. High fat diet (HFD) increases intracellular NADH. We investigated the effect of CtBP1 hyperactivation by HFD intake on mouse breast carcinogenesis. We generated a MeS-like disease in female mice by chronically feeding animals with HFD. MeS increased postnatal mammary gland development and generated prominent duct patterns with markedly increased CtBP1 and Cyclin D1 expression. CtBP1 induced breast cancer cells proliferation. Serum from animals with MeS enriched the stem-like/progenitor cell population from breast cancer cells. CtBP1 increased breast tumor growth in MeS mice modulating multiple genes and miRNA expression implicated in cell proliferation, progenitor cells phenotype, epithelial to mesenchymal transition, mammary development and cell communication in the xenografts. These results define a novel function for CtBP1 in breast carcinogenesis. PMID:26933806

  20. CacyBP/SIP binds ERK1/2 and affects transcriptional activity of Elk-1.

    PubMed

    Kilanczyk, Ewa; Filipek, Slawomir; Jastrzebska, Beata; Filipek, Anna

    2009-02-27

    In this work we showed for the first time that mouse CacyBP/SIP interacts with extracellular signal regulated kinases 1 and 2 (ERK1/2). We also established that a calcium binding protein, S100A6, competes for this interaction. Moreover, the E217K mutant of CacyBP/SIP does not bind significantly to ERK1/2 although it retains the ability to interact with S100A6. Molecular modeling shows that the E217K mutation in the 189-219 CacyBP/SIP fragment markedly changes its electrostatic potential, suggesting that the binding with ERK1/2 might have an electrostatic character. We also demonstrate that CacyBP/SIP-ERK1/2 interaction inhibits phosphorylation of the Elk-1 transcription factor in vitro and in the nuclear fraction of NB2a cells. Altogether, our data suggest that the binding of CacyBP/SIP with ERK1/2 might regulate Elk-1 phosphorylation/transcriptional activity and that S100A6 might further modulate this effect via Ca(2+)-dependent interaction with CacyBP/SIP and competition with ERK1/2.

  1. The CacyBP/SIP protein is sumoylated in neuroblastoma NB2a cells.

    PubMed

    Wasik, Urszula; Filipek, Anna

    2013-11-01

    The Calcyclin binding protein and Siah-1 interacting protein (CacyBP/SIP) protein is highly expressed in mammalian brain as well as in neuroblastoma NB2a cells and pheochromocytoma PC12 cells. This protein interacts with several targets such as cytoskeletal proteins or ERK1/2 kinase and seems to be involved in many cellular processes. In this work we examined a post-translational modification of CacyBP/SIP which might have an effect on its function. Since theoretical analysis of the amino acid sequence of CacyBP/SIP indicated several lysine residues which could potentially be sumoylated we checked experimentally whether this protein might be modified by SUMO attachment. We have shown that indeed CacyBP/SIP bound the E2 SUMO ligase, Ubc9, in neuroblastoma NB2a cell extract and was sumoylated in these cells. By fractionation of NB2a cell extract we have found that, contrary to the majority of SUMO-modified proteins, sumoylated CacyBP/SIP is present in the cytoplasmic and not in the nuclear fraction. We have also established that lysine 16 is the residue which undergoes sumoylation in the CacyBP/SIP protein.

  2. CacyBP/SIP protein is important for the proliferation of human glioma cells.

    PubMed

    Shi, Hengliang; Gao, Yong; Tang, Yuan; Wu, Yuxuan; Gong, Hui; Du, Jin; Zheng, Bao; Hu, Jinxia; Shi, Qiong; Yu, Rutong

    2014-04-01

    Recently, calcyclin-binding protein or Siah-1-interacting protein (CacyBP/SIP), a component of a novel ubiquitinylation pathway, could regulate the β-catenin degradation (Fukushima et al., Immunity 2006, 24, 29-39). However, the potential role of CacyBP/SIP itself in human glioma cells has not been clarified. Here, we found that CacyBP/SIP was expressed highly in human glioma tissues. Silencing of CacyBP/SIP by short-hairpin RNA severely suppressed the proliferation of human glioma cell U251, which was at least partly mediated by downregulation of phospho-Akt (p-Akt) and phospho-β-catenin (p-β-catenin) as well as upregulation of p53 and p21. Furthermore, overexpression of CacyBP/SIP obviously promoted the proliferation of human glioma U251, which exhibited the exactly contrary trend in the expression of p-Akt, p-β-catenin, p53, and p21. Taken together, these findings suggest that CacyBP/SIP plays important roles in the proliferation of human glioma cell which might be involved in the development of human glioma.

  3. CacyBP/SIP binds ERK1/2 and affects transcriptional activity of Elk-1

    SciTech Connect

    Kilanczyk, Ewa; Filipek, Slawomir; Jastrzebska, Beata; Filipek, Anna

    2009-02-27

    In this work we showed for the first time that mouse CacyBP/SIP interacts with extracellular signal regulated kinases 1 and 2 (ERK1/2). We also established that a calcium binding protein, S100A6, competes for this interaction. Moreover, the E217K mutant of CacyBP/SIP does not bind significantly to ERK1/2 although it retains the ability to interact with S100A6. Molecular modeling shows that the E217K mutation in the 189-219 CacyBP/SIP fragment markedly changes its electrostatic potential, suggesting that the binding with ERK1/2 might have an electrostatic character. We also demonstrate that CacyBP/SIP-ERK1/2 interaction inhibits phosphorylation of the Elk-1 transcription factor in vitro and in the nuclear fraction of NB2a cells. Altogether, our data suggest that the binding of CacyBP/SIP with ERK1/2 might regulate Elk-1 phosphorylation/transcriptional activity and that S100A6 might further modulate this effect via Ca{sup 2+}-dependent interaction with CacyBP/SIP and competition with ERK1/2.

  4. Translation control during prolonged mTORC1 inhibition mediated by 4E-BP3

    PubMed Central

    Tsukumo, Yoshinori; Alain, Tommy; Fonseca, Bruno D.; Nadon, Robert; Sonenberg, Nahum

    2016-01-01

    Targeting mTORC1 is a highly promising strategy in cancer therapy. Suppression of mTORC1 activity leads to rapid dephosphorylation of eIF4E-binding proteins (4E-BP1–3) and subsequent inhibition of mRNA translation. However, how the different 4E-BPs affect translation during prolonged use of mTOR inhibitors is not known. Here we show that the expression of 4E-BP3, but not that of 4E-BP1 or 4E-BP2, is transcriptionally induced during prolonged mTORC1 inhibition in vitro and in vivo. Mechanistically, our data reveal that 4E-BP3 expression is controlled by the transcription factor TFE3 through a cis-regulatory element in the EIF4EBP3 gene promoter. CRISPR/Cas9-mediated EIF4EBP3 gene disruption in human cancer cells mitigated the inhibition of translation and proliferation caused by prolonged treatment with mTOR inhibitors. Our findings show that 4E-BP3 is an important effector of mTORC1 and a robust predictive biomarker of therapeutic response to prolonged treatment with mTOR-targeting drugs in cancer. PMID:27319316

  5. The closure of Pak1-dependent macropinosomes requires the phosphorylation of CtBP1/BARS.

    PubMed

    Liberali, Prisca; Kakkonen, Elina; Turacchio, Gabriele; Valente, Carmen; Spaar, Alexander; Perinetti, Giuseppe; Böckmann, Rainer A; Corda, Daniela; Colanzi, Antonino; Marjomaki, Varpu; Luini, Alberto

    2008-04-09

    Membrane fission is an essential process in membrane trafficking and other cellular functions. While many fissioning and trafficking steps are mediated by the large GTPase dynamin, some fission events are dynamin independent and involve C-terminal-binding protein-1/brefeldinA-ADP ribosylated substrate (CtBP1/BARS). To gain an insight into the molecular mechanisms of CtBP1/BARS in fission, we have studied the role of this protein in macropinocytosis, a dynamin-independent endocytic pathway that can be synchronously activated by growth factors. Here, we show that upon activation of the epidermal growth factor receptor, CtBP1/BARS is (a) translocated to the macropinocytic cup and its surrounding membrane, (b) required for the fission of the macropinocytic cup and (c) phosphorylated on a specific serine that is a substrate for p21-activated kinase, with this phosphorylation being essential for the fission of the macropinocytic cup. Importantly, we also show that CtBP1/BARS is required for macropinocytic internalization and infection of echovirus 1. These results provide an insight into the molecular mechanisms of CtBP1/BARS activation in membrane fissioning, and extend the relevance of CtBP1/BARS-induced fission to human viral infection.

  6. Occurrence of 4-tert-butylphenol (4-t-BP) biodegradation in an aquatic sample caused by the presence of Spirodela polyrrhiza and isolation of a 4-t-BP-utilizing bacterium.

    PubMed

    Ogata, Yuka; Toyama, Tadashi; Yu, Ning; Wang, Xuan; Sei, Kazunari; Ike, Michihiko

    2013-04-01

    Although 4-tert-butylphenol (4-t-BP) is a serious aquatic pollutant, its biodegradation in aquatic environments has not been well documented. In this study, 4-t-BP was obviously and repeatedly removed from water from four different environments in the presence of Spirodela polyrrhiza, giant duckweed, but 4-t-BP persisted in the environmental waters in the absence of S. polyrrhiza. Also, 4-t-BP was not removed from autoclaved pond water with sterilized S. polyrrhiza. These results suggest that the 4-t-BP removal from the environmental waters was caused by biodegradation stimulated by the presence of S. polyrrhiza rather than by uptake by the plant. Moreover, Sphingobium fuliginis OMI capable of utilizing 4-t-BP as a sole carbon and energy source was isolated from the S. polyrrhiza rhizosphere. Strain OMI degraded 4-t-BP via a meta-cleavage pathway, and also degraded a broad range of alkylphenols with linear or branched alkyl side chains containing two to nine carbon atoms. Root exudates of S. polyrrhiza stimulated 4-t-BP degradation and cell growth of strain OMI. Thus, the stimulating effects of S. polyrrhiza root exudates on 4-t-BP-degrading bacteria might have contributed to 4-t-BP removal in the environmental waters with S. polyrrhiza. These results demonstrate that the S. polyrrhiza-bacteria association may be applicable to the removal of highly persistent 4-t-BP from wastewaters or polluted aquatic environments.

  7. 15q11.2 microdeletion (BP1-BP2) and developmental delay, behaviour issues, epilepsy and congenital heart disease: a series of 52 patients.

    PubMed

    Vanlerberghe, Clémence; Petit, Florence; Malan, Valérie; Vincent-Delorme, Catherine; Bouquillon, Sonia; Boute, Odile; Holder-Espinasse, Muriel; Delobel, Bruno; Duban, Bénédicte; Vallee, Louis; Cuisset, Jean-Marie; Lemaitre, Marie-Pierre; Vantyghem, Marie-Christine; Pigeyre, Marie; Lanco-Dosen, Sandrine; Plessis, Ghislaine; Gerard, Marion; Decamp, Matthieu; Mathieu, Michèle; Morin, Gilles; Jedraszak, Guillaume; Bilan, Frédéric; Gilbert-Dussardier, Brigitte; Fauvert, Delphine; Roume, Joëlle; Cormier-Daire, Valérie; Caumes, Roseline; Puechberty, Jacques; Genevieve, David; Sarda, Pierre; Pinson, Lucie; Blanchet, Patricia; Lemeur, Nathalie; Sheth, Frenny; Manouvrier-Hanu, Sylvie; Andrieux, Joris

    2015-03-01

    Proximal region of chromosome 15 long arm is rich in duplicons that, define five breakpoints (BP) for 15q rearrangements. 15q11.2 microdeletion between BP1 and BP2 has been previously associated with developmental delay and atypical psychological patterns. This region contains four highly-conserved and non-imprinted genes: NIPA1, NIPA2, CYFIP1, TUBGCP5. Our goal was to investigate the phenotypes associated with this microdeletion in a cohort of 52 patients. This copy number variation (CNV) was prevalent in 0.8% patients presenting with developmental delay, psychological pattern issues and/or multiple congenital malformations. This was studied by array-CGH at six different French Genetic laboratories. We collected data from 52 unrelated patients (including 3 foetuses) after excluding patients with an associated genetic alteration (known CNV, aneuploidy or known monogenic disease). Out of 52 patients, mild or moderate developmental delay was observed in 68.3%, 85.4% had speech impairment and 63.4% had psychological issues such as Attention Deficit and Hyperactivity Disorder, Autistic Spectrum Disorder or Obsessive-Compulsive Disorder. Seizures were noted in 18.7% patients and associated congenital heart disease in 17.3%. Parents were analysed for abnormalities in the region in 65.4% families. Amongst these families, 'de novo' microdeletions were observed in 18.8% and 81.2% were inherited from one of the parents. Incomplete penetrance and variable expressivity were observed amongst the patients. Our results support the hypothesis that 15q11.2 (BP1-BP2) microdeletion is associated with developmental delay, abnormal behaviour, generalized epilepsy and congenital heart disease. The later feature has been rarely described. Incomplete penetrance and variability of expression demands further assessment and studies.

  8. Transcriptional down-regulation of Brca1 and E-cadherin by CtBP1 in breast cancer.

    PubMed

    Deng, Yu; Deng, Hui; Liu, Jing; Han, Gangwen; Malkoski, Stephen; Liu, Bolin; Zhao, Rui; Wang, Xiao-Jing; Zhang, Qinghong

    2012-06-01

    Carboxyl-terminal binding protein 1 (CtBP1) is a transcriptional co-repressor with oncogenic potential. Immunohistochemistry staining using human breast cancer tissue arrays revealed that 92% of invasive ductal breast cancer cases have CtBP1-positive staining compared to 4% CtBP1-positive in normal breast tissue. To explore the functional impact of CtBP1 in breast cancer, we examined CtBP1's transcriptional regulation of known tumor suppressors, breast cancer susceptibility gene 1 (Brca1), and E-cadherin. We found CtBP1 was recruited to the promoter regions of Brca1 and E-cadherin genes in breast cancer cells. Concomitantly, Brca1 loss was detected in 57% and E-cadherin loss was detected in 76% of human invasive ductal breast cancers, and correlated with CtBP1 nuclear staining in these lesions. Importantly, siRNA knock down of CtBP1 restored Brca1 and E-cadherin expression in breast cancer cell lines, implying CtBP1 down-regulates Brca1 and E-cadherin genes in human breast cancer. This study provides evidence that although genetic loss of Brca1 and E-cadherin are infrequent in breast cancer, they are down-regulated at the transcriptional level by CtBP1 expression. Thus, CtBP1 activation could be a potential biomarker for breast cancer development.

  9. cMyBP-C was decreased via KLHL3-mediated proteasomal degradation in congenital heart diseases.

    PubMed

    Wang, Leitong; Lai, Guangrui; Chu, Guoming; Liang, Xiaoyan; Zhao, Yanyan

    2017-03-15

    Cardiac myosin binding protein C (cMyBP-C) is a cardiac structural and regulatory protein; mutations of cMyBP-C are frequently associated with hypertrophic cardiomyopathy (HCM) and dilated cardiomyopathy (DCM). Cardiac special transcription factors may regulate the expression of cMyBP-C. However, the role of cMyBP-C in congenital heart diseases (CHD) remains poorly understood. In the current study, western blotting and the MRM approach showed that cMyBP-C expression was significantly reduced in fetuses with CHD compared to those without. Furthermore, we found that cMyBP-C interacted with KLHL3 by immunoprecipitation and immunofluorescence, and the degradation of cMyBP-C was caused by KLHL3-mediated ubiquitination. In addition, homocysteine (Hcy, a risk factor of CHD) treatment caused a decrease in cMyBP-C and an increase in KLHL3 expression, and the proteasome inhibitor MG132 reversed the Hcy-induced reduction of cMyBP-C expression. Finally, we verified that reduced cMyBP-C by Hcy promoted apoptosis in cardiomyocytes. These results demonstrate that Hcy decreases the expression of cMyBP-C through a KLHL3-mediated ubiquitin-proteasome pathway, and thereby influences heart development.

  10. 180-kD bullous pemphigoid antigen (BP180) is deficient in generalized atrophic benign epidermolysis bullosa.

    PubMed Central

    Jonkman, M F; de Jong, M C; Heeres, K; Pas, H H; van der Meer, J B; Owaribe, K; Martinez de Velasco, A M; Niessen, C M; Sonnenberg, A

    1995-01-01

    Generalized atrophic benign epidermolysis bullosa (GABEB) is a form of nonlethal junctional epidermolysis bullosa characterized by universal alopecia and atrophy of the skin. We report a deficiency of the 180-kD bullous pemphigoid antigen in three patients with GABEB from unrelated families. We screened specimens of clinically normal skin from nine junctional epidermolysis bullosa patients (3 GABEB, 4 lethal, 1 cicatricial, 1 pretibial) by immunofluorescence using monoclonal antibodies to the 180-kD and 230-kD bullous pemphigoid antigens (BP180 and BP230). In the skin of the three GABEB patients there was no reactivity with antibodies to BP180, whereas staining for BP230 was normal. In the skin of the other six, non-GABEB patients, included in this study the expression of BP180 and BP230 was normal. Immunoblot analysis of cultured keratinocytes from one of the GABEB patients also failed to detect BP180 antigen, whereas BP230 was present in normal amounts. The deficient expression of BP180 is reflected in the RNA message, as in Northern blot analysis a reduced amount of BP180 transcripts, although of normal length, were detected. Interestingly, in another GABEB patient there were not-involved areas of skin, in which blistering could not be induced by rubbing. Biopsy material from these areas showed interrupted staining for BP180. There was no staining for BP180 in areas of clinically normal but involved skin of this patient. In conclusion, this study reveals that the BP180 antigen is deficient and the BP180 mRNA is reduced in generalized atrophic benign epidermolysis bullosa. Images PMID:7883981

  11. Molecular characterization and expression of CD2BP2 in Nile tilapia (Oreochromis niloticus) in response to Streptococcus agalactiae stimulus.

    PubMed

    Gan, Zhen; Wang, Bei; Lu, Yishan; Cai, Shuanghu; Cai, Jia; Jian, JiChang; Wu, Zaohe

    2014-09-10

    CD2BP2 (CD2 cytoplasmic tail binding protein 2), one of several proteins interacting with the cytoplasmic tail of CD2, plays a crucial role in CD2-triggered T cell activation and nuclear splicing. The studies on CD2BP2 have tended to be confined to a few mammals, and little information is available to date regarding fish CD2BP2. In this paper, a CD2BP2 gene (On-CD2BP2) was cloned from Nile tilapia, Oreochromis niloticus. Sequence analysis showed that the full length of On-CD2BP2 cDNA was 1429 bp, containing a 5'untranslated region (UTR) of 111 bp, a 3'-UTR of 193 bp and an open reading frame of 1125 bp which is encoding 374 amino acids. Two important structural features, a GYF domain and a consensus motif GPFXXXXMXXWXXXGYF were detected in the deduced amino acid sequence of On-CD2BP2, and the deduced genomic structure of On-CD2BP2 was similar to the known CD2BP2. The mRNA expression of On-CD2BP2 in various tissues of Nile tilapia was analyzed by fluorescent quantitative real-time PCR. In healthy Nile tilapia, the On-CD2BP2 transcripts were mainly detected in the head kidney and spleen. While vaccinated with inactivated Streptococcus agalactiae, the On-CD2BP2 mRNA expression was significantly up-regulated in the head kidney, spleen and brain 48 h post immunization. Moreover, there was a clear time-dependent expression pattern of On-CD2BP2 after immunization and the expression reached the highest level at 24h in the brain and 48 h in the head kidney and spleen. This is the first report of proving the presence of a CD2BP2 ortholog in fish, and investigating its tissue distribution and expression profile in response to bacterial stimulus. These findings indicated that On-CD2BP2 may play an important role in the immune response to bacteria in Nile tilapia.

  12. RanBP3 Regulates Melanoma Cell Proliferation via Selective Control of Nuclear Export.

    PubMed

    Pathria, Gaurav; Garg, Bhavuk; Wagner, Christine; Garg, Kanika; Gschaider, Melanie; Jalili, Ahmad; Wagner, Stephan N

    2016-01-01

    Chromosome region maintenance 1-mediated nucleocytoplasmic transport has been shown as a potential anticancer target in various malignancies. However, the role of the most characterized chromosome region maintenance 1 cofactor ran binding protein 3 (RanBP3) in cancer cell biology has never been investigated. Utilizing a loss-of-function experimental setting in a vast collection of genetically varied melanoma cell lines, we observed the requirement of RanBP3 in melanoma cell proliferation and survival. Mechanistically, we suggest the reinstatement of transforming growth factor-β (TGF-β)-Smad2/3-p21(Cip1) tumor-suppressor axis as part of the RanBP3 silencing-associated antiproliferative program. Employing extensive nuclear export sequence analyses and immunofluorescence-based protein localization studies, we further present evidence suggesting the requirement of RanBP3 function for the nuclear exit of the weak nuclear export sequence-harboring extracellular signal-regulated kinase protein, although it is dispensable for general CRM1-mediated nuclear export of strong nuclear export sequence-harboring cargoes. Rendering mechanistic support to RanBP3 silencing-mediated apoptosis, consequent to extracellular signal-regulated kinase nuclear entrapment, we observed increased levels of cytoplasmically restricted nonphosphorylated/active proapoptotic Bcl-2-antagonist of cell death (BAD) protein. Last, we present evidence suggesting the frequently activated mitogen-activated protein kinase signaling in melanoma as a potential founding basis for a deregulated post-translational control of RanBP3 activity. Collectively, the presented data suggest RanBP3 as a potential target for therapeutic intervention in human melanoma.

  13. A2BP1 gene polymorphisms association with olanzapine-induced weight gain.

    PubMed

    Dong, Licai; Yan, Hao; Huang, Xuebing; Hu, Xiaofeng; Yang, Yongfeng; Ma, Cuicui; Du, Bo; Lu, Tianlan; Jin, Chao; Wang, Lifang; Yu, Hao; Dong, Zheng; Li, Wenqiang; Ruan, Yanyan; Zhang, Hongyan; Zhang, Hongxing; Mi, Weifeng; Ma, Wenbin; Li, Keqing; Lv, Luxian; Zhang, Dai; Yue, Weihua

    2015-09-01

    The ataxin-2 binding protein 1 (A2BP1) gene is reported to be one of the susceptibility genes in schizophrenia, autism, and obesity. The aim of this study was to explore the association of A2BP1 gene polymorphisms with antipsychotic induced weight gain (AIWG) in Chinese Han population. Three hundred and twenty-eight patients with schizophrenia were followed-up for an 8-week period of treatment with olanzapine. The fasting weights of 328 patients were measured before and after the 8-week course of treatment. Four single nucleotide polymorphisms (SNPs: rs8048076, rs1478697, rs10500331, and rs4786847) of the A2BP1 gene were genotyped by polymerase chain reaction (PCR). We analyzed putative association of A2BP1 polymorphisms with AIWG of olanzapine using linear regression analysis and found that SNP rs1478697 was significantly associated with AIWG caused by olanzapine (p=0.0012; Bonferroni corrected p=0.0048). The association was replicated in another independent sample including 208 first-episode and drug-naïve patients presenting with schizophrenia after a 4-week treatment with olanzapine (p=0.0092; Bonferroni corrected p=0.0368; meta p=5.33×10(-5)). To explore the biological plausibility of A2BP1 in the pathogenesis of AIWG, we made expression analyses and eQTL analyses; these analyses showed that A2BP1 was highly expressed in whole brain tissues using the HBT database, and that rs1478697 has an expression quantitative trait locus effect in human cerebellar cortex tissues using the BRAINEAC database (p=2.50E-04). In conclusion, the rs1478697 in A2BP1 may be associated with AIWG induced by 8-week treatment with olanzapine.

  14. A central role for R7bp in the regulation of itch sensation.

    PubMed

    Pandey, Mritunjay; Zhang, Jian-Hua; Mishra, Santosh K; Adikaram, Poorni R; Harris, Benjamin; Kahler, John F; Loshakov, Anna; Sholevar, Roxanne; Genis, Allison; Kittock, Claire; Kabat, Juraj; Ganesan, Sundar; Neubig, Richard R; Hoon, Mark A; Simonds, William F

    2017-01-27

    Itch is a protective sensation producing a desire to scratch. Pathologic itch can be a chronic symptom of illnesses such as uremia, cholestatic liver disease, neuropathies and dermatitis, however current therapeutic options are limited. Many types of cell surface receptors, including those present on cells in the skin, on sensory neurons and on neurons in the spinal cord, have been implicated in itch signaling. The role of G protein signaling in the regulation of pruriception is poorly understood. We identify here 2 G protein signaling components whose mutation impairs itch sensation. R7bp (a.k.a. Rgs7bp) is a palmitoylated membrane anchoring protein expressed in neurons that facilitates Gαi/o -directed GTPase activating protein activity mediated by the Gβ5/R7-RGS complex. Knockout of R7bp diminishes scratching responses to multiple cutaneously applied and intrathecally-administered pruritogens in mice. Knock-in to mice of a GTPase activating protein-insensitive mutant of Gαo (Gnao1 G184S/+) produces a similar pruriceptive phenotype. The pruriceptive defect in R7bp knockout mice was rescued in double knockout mice also lacking Oprk1, encoding the G protein-coupled kappa-opioid receptor whose activation is known to inhibit itch sensation. In a model of atopic dermatitis (eczema), R7bp knockout mice showed diminished scratching behavior and enhanced sensitivity to kappa opioid agonists. Taken together, our results indicate that R7bp is a key regulator of itch sensation and suggest the potential targeting of R7bp-dependent GTPase activating protein activity as a novel therapeutic strategy for pathological itch.

  15. ALS mutant SOD1 interacts with G3BP1 and affects stress granule dynamics.

    PubMed

    Gal, Jozsef; Kuang, Lisha; Barnett, Kelly R; Zhu, Brian Z; Shissler, Susannah C; Korotkov, Konstantin V; Hayward, Lawrence J; Kasarskis, Edward J; Zhu, Haining

    2016-10-01

    Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease. Mutations in Cu/Zn superoxide dismutase (SOD1) are responsible for approximately 20 % of the familial ALS cases. ALS-causing SOD1 mutants display a gain-of-toxicity phenotype, but the nature of this toxicity is still not fully understood. The Ras GTPase-activating protein-binding protein G3BP1 plays a critical role in stress granule dynamics. Alterations in the dynamics of stress granules have been reported in several other forms of ALS unrelated to SOD1. To our surprise, the mutant G93A SOD1 transgenic mice exhibited pathological cytoplasmic inclusions that co-localized with G3BP1-positive granules in spinal cord motor neurons. The co-localization was also observed in fibroblast cells derived from familial ALS patient carrying SOD1 mutation L144F. Mutant SOD1, unlike wild-type SOD1, interacted with G3BP1 in an RNA-independent manner. Moreover, the interaction is specific for G3BP1 since mutant SOD1 showed little interaction with four other RNA-binding proteins implicated in ALS. The RNA-binding RRM domain of G3BP1 and two particular phenylalanine residues (F380 and F382) are critical for this interaction. Mutant SOD1 delayed the formation of G3BP1- and TIA1-positive stress granules in response to hyperosmolar shock and arsenite treatment in N2A cells. In summary, the aberrant mutant SOD1-G3BP1 interaction affects stress granule dynamics, suggesting a potential link between pathogenic SOD1 mutations and RNA metabolism alterations in ALS.

  16. Relationship between Ambulatory BP and Clinical Outcomes in Patients with Hypertensive CKD

    PubMed Central

    Rahman, Mahboob; Hu, Bo; Appel, Lawrence J.; Charleston, Jeanne; Contreras, Gabriel; Faulkner, Marquetta L.; Hiremath, Leena; Jamerson, Kenneth A.; Lea, Janice P.; Lipkowitz, Michael S.; Pogue, Velvie A.; Rostand, Stephen G.; Smogorzewski, Miroslaw J.; Wright, Jackson T.; Greene, Tom; Gassman, Jennifer; Wang, Xuelei; Phillips, Robert A.

    2012-01-01

    Summary Background and objectives Abnormal ambulatory BP (ABP) profiles are commonplace in CKD, yet the prognostic value of ABP for renal and cardiovascular outcomes is uncertain. This study assessed the relationship of baseline ABP profiles with CKD progression and subsequent cardiovascular outcomes to determine the prognostic value of ABP beyond that of clinic BP measurements. Design, setting, participants, & measurements Between 2002 and 2003, 617 African Americans with hypertensive CKD treated to a clinic BP goal of <130/80 mmHg were enrolled in this prospective, observational study. Participants were followed for a median of 5 years. Primary renal outcome was a composite of doubling of serum creatinine, ESRD, or death. The primary cardiovascular outcome was a composite of myocardial infarction, hospitalized congestive heart failure, stroke, revascularization procedures, cardiovascular death, and ESRD. Results Multivariable Cox proportional hazard analysis showed that higher 24-hour systolic BP (SBP), daytime, night-time, and clinic SBP were each associated with subsequent renal (hazard ratio, 1.17–1.28; P<0.001) and cardiovascular outcomes (hazard ratio, 1.22–1.32; P<0.001). After controlling for clinic SBP, ABP measures were predictive of renal outcomes in participants with clinic SBP <130 mmHg (P<0.05 for interaction). ABP predicted cardiovascular outcomes with no interaction based on clinic BP control. Conclusions ABP provides additional information beyond that of multiple clinic BP measures in predicting renal and cardiovascular outcomes in African Americans with hypertensive CKD. The primary utility of ABP in these CKD patients was to identify high-risk individuals among those patients with controlled clinic BP. PMID:22935847

  17. BpMADS4 has a central role in inflorescence initiation in silver birch (Betula pendula).

    PubMed

    Elo, Annakaisa; Lemmetyinen, Juha; Novak, Anu; Keinonen, Kaija; Porali, Ilkka; Hassinen, Minna; Sopanen, Tuomas

    2007-09-01

    Acceleration of flowering would be beneficial for breeding trees with a long juvenile phase; conversely, inhibition of flowering would prevent the spread of transgenes from the genetically modified trees. We have previously isolated and characterized several MADS genes from silver birch (Betula pendula Roth). In this study, we investigated the more detailed function of one of them, BpMADS4, a member of the APETALA1/FRUITFULL group of MADS genes. The expression of BpMADS4 starts at very early stage of the male and female inflorescence development and the activity is high in the apex of the developing inflorescence. Later, some expression is detected in the bracts and in the flower initials. Ectopic expression of BpMADS4 accelerates flowering dramatically in normally flowering clones and also in the early-flowering birch clone, in which the earliest line flowered about 11 days after rooting, when the saplings were only 3 cm high. The birches transformed with the BpMADS4 antisense construct showed remarkable delay in flowering and the number of flowering individuals was reduced. Two of the transformed lines did not show any signs of flower development during our 2-year study, whereas all the control plants formed inflorescences within 107 days. Our results show that BpMADS4 has a critical role in the initiation of birch inflorescence development and that BpMADS4 seems to be involved in the transition from vegetative to reproductive development. Therefore, BpMADS4 provides a promising tool for the genetic enhancement of forest trees.

  18. Lake level changes in Hala Lake(NW China) based on ostracodassemblages during the LGM and Post-LGM

    NASA Astrophysics Data System (ADS)

    Yan, D.; Wuennemann, B.

    2012-12-01

    The Hala Lake, located in the Qilian Mountains, Qinghai Province, China, at 4078 m a.s.l. may archive in its sediments hydrological and climate changes during the Late Quaternary time, as it is close to the area impacted by the East-Asian Summer monsoon and westerly-driven air masses. Based on the sediment core H7, which was taken in the center of the lake at 65m water depth,ostracod assemblages and stable isotopes from ostracode shells were investigated in details. Three main species were found, which are common species in high altitude saline lakes of the Tibetan Plateau: Leucocythere sp.,Limnocythereinopinata and Eucypris sp.They started to occur in deeper part of H7,indicating an early onset of favorable living conditions during the LGM and post-LGM periods. Besides, algae occurred between 25 and 32m water depth. According to the unevenly distributed amount of ostracods and oxygen isotope data, our results indicate important lake level changes during the global LGM and Lateglacial. The lake experienced lowest levels of 25-50 m below the present water line. Ostracods disappeared with the onset of the early Holocene.A stepwise refilling started already at ca. 16 kyr BP and reached -25 m level during the Bølling/Allerød warm phase at ca. 13.5 kyr BP.Latest at ca.7.6 kyr BP, the lake reached a stable highstand similar to the present level until ca.6 kyr BPas . The subsequent lake development remains unclear due to strong mismatches of the data but may indicate a general trend to deteriorating conditions and lake level lowstands at ca. 5.0-4.2, 2.0 and at around 0.5 kyr BP.; Ostracods Distribution in H2 ; Ostracods plate in Hala lake

  19. Non-Ideal p-n junction Diode of Sb{sub x}Se{sub 1-x}(x = 0.4, 0.5, 0.6, 0.7) Thin Films

    SciTech Connect

    Mustafa, Falah I.; Gupta, Shikha; Goyal, N.; Tripathi, S. K.

    2011-12-12

    We have made diodes consisting of the same alloy i.e. Sb{sub x}Se{sub 1-x}(x = 0.4, 0.5, 0.6 and 0.7), but change the concentration of Sb metal from 40% to 70% atomic weight percentage. It is observed from the Hall measurements that the nature of charge carriers have changed from p- to n-type at x = 0.6 for Sb{sub x}Se{sub 1-x}. We have measured I-V characteristics of four p-n junction diodes i.e. p-Sb{sub 2}Se{sub 3}/n-Sb{sub 3}Se{sub 2}, p-Sb{sub 2}Se{sub 3}/n-Sb{sub 7}Se{sub 3}, p-SbSe/n-Sb{sub 3}Se{sub 2}, p-SbSe/n-Sb{sub 7}Se{sub 3}. From the I-V plots we have calculated the parameters as built-in voltage (V{sub bi}), forward resistance (R{sub f}), ideal factor (n), saturation current (I{sub o}), breakdown current (I{sub Bd}) and breakdown voltage (V{sub Bd}).

  20. Effects of Cooling Rates on Glass Formation and Magnetic Behavior for the Fe73.0C7.0Si3.3B5.0P8.7Mo3.0 Bulk Metallic Glass

    NASA Astrophysics Data System (ADS)

    Gao, J. E.; Li, H. X.; Jiang, F.; Winiarski, B.; Withers, P. J.; Liaw, P. K.; Lu, Z. P.

    2013-05-01

    In this paper, effects of cooling rates on glass formation and magnetic behavior of the Fe73.0C7.0Si3.3B5.0P8.7Mo3.0 (at. pct) alloy were investigated via different purging gases ( i.e., helium and argon) during suction casting. X-ray diffraction patterns and transmission electron microscopy characterization confirmed that the maximum attainable diameter for glass formation is increased from 5 to 7 mm with the helium as the purging gas, relative to the argon. Meanwhile, the coercivity value ( H c) of the sample cast in helium is almost 5 times larger than that fabricated in argon, although the magnetization saturation in these two alloys is similar. Our pair distribution function analysis, density, and positron annihilation lifetime spectroscopy measurements indicated that the sample cast in helium possesses more free volume; however, the difference between them is insubstantial. Further, experimental results revealed that the residual stress in the samples cast under helium is much larger than that in those prepared in Argon, which could be responsible for the abrupt change in the coercivity.

  1. The putative nebula of the Wolf-Rayet WR 60 star: a case of mistaken identity and reclassification as a new supernova remnant G310.5+0.8

    NASA Astrophysics Data System (ADS)

    Stupar, M.; Parker, Q. A.; Filipović, M. D.

    2011-04-01

    We present narrow band AAO/UKST H α images and medium and low resolution optical spectra of a nebula shell putatively associated with the Wolf-Rayet star WR 60. We also present the first identification of this shell in the radio regime at 843 MHz and at 4850 MHz from the Sydney University Molonglo Sky Survey (SUMSS), and from the Parkes-MIT-NRAO (PMN) survey respectively. This radio emission closely follows the optical emission. The optical spectra from the shell exhibits the typical shock excitation signatures sometimes seen in Wolf-Rayet stellar ejecta but also common to supernova remnants. A key finding however, is that the WR 60 star, is not, in fact, anywhere near the geometrical centre of the putative arcuate nebula ejecta as had been previously stated. This was due to an erroneous positional identification for the star in the literature which we now correct. This new identification calls into serious question any association of the nebula with WR 60 as such nebula are usually quite well centred on the WR stars themselves. We now propose that this fact combined with our new optical spectra, deeper H α imaging and newly identified radio structures actually imply that the WR 60 nebula should be reclassified as an unassociated new supernova remnant which we designate G310.5+0.8.

  2. Fabrications and characterizations of high performance 1.2 kV, 3.3 kV, and 5.0 kV class 4H-SiC power SBDs

    NASA Astrophysics Data System (ADS)

    Qing-Wen, Song; Xiao-Yan, Tang; Hao, Yuan; Yue-Hu, Wang; Yi-Meng, Zhang; Hui, Guo; Ren-Xu, Jia; Hong-Liang, Lv; Yi-Men, Zhang; Yu-Ming, Zhang

    2016-04-01

    In this paper, 1.2 kV, 3.3 kV, and 5.0 kV class 4H-SiC power Schottky barrier diodes (SBDs) are fabricated with three N-type drift layer thickness values of 10 μm, 30 μm, and 50 μm, respectively. The avalanche breakdown capabilities, static and transient characteristics of the fabricated devices are measured in detail and compared with the theoretical predictions. It is found that the experimental results match well with the theoretical calculation results and are very close to the 4H-SiC theoretical limit line. The best achieved breakdown voltages (BVs) of the diodes on the 10 μm, 30 μm, and 50 μm epilayers are 1400 V, 3320 V, and 5200 V, respectively. Differential specific-on resistances (R on-sp) are 2.1 mΩ ·cm2, 7.34 mΩ·cm2, and 30.3 mΩ·cm2, respectively. Project supported by the National Natural Science Foundation of China (Grant Nos. 61404098, 61176070, and 61274079), the Doctoral Fund of Ministry of Education of China (Grant Nos. 20110203110010 and 20130203120017), the National Key Basic Research Program of China (Grant No. 2015CB759600), and the Key Specific Projects of Ministry of Education of China (Grant No. 625010101).

  3. Defect chalcopyrite Cu(In{sub 1-x}Ga{sub x}){sub 3}Se{sub 5} (0

    SciTech Connect

    Contreras, M.A.; Wiesner, H.; Niles, D.; Ramanathan, K.; Matson, R.

    1996-05-01

    Crystallographic, optical, and electrical properties of defect chalcopyrite Cu(In{sub 1{minus}x}Ga{sub x}){sub 3}Se{sub 5} (00.3) is due to a relatively inferior character - both structural and electrical - at the very chalcopyrite/defect chalcopyrite interface. They demonstrate that this situation can be circumvented (for absorbers with x>0.3) by properly engineering such an interface by reducing Ga content in the region near the surface of the absorber.

  4. Structural, dielectric, ferroelectric, and electrocaloric properties of 2% Gd2O3 doping (Na0.5Bi0.5)0.94Ba0.06TiO3 ceramics

    NASA Astrophysics Data System (ADS)

    Turki, O.; Slimani, A.; Seveyrat, L.; Sebald, G.; Perrin, V.; Sassi, Z.; Khemakhem, H.; Lebrun, L.

    2016-08-01

    Structural, dielectric, and ferroelectric properties, and electrocaloric effects of pure and Gd doped ( Na0.5 Bi 0.5 ) 0.94 Ba 0.06 TiO 3 ceramics prepared by the conventional solid-solid method have been carried out. The X-ray diffraction analysis confirms a pure perovskite structure with the coexistence of tetragonal and rhombohedra structures in both powders. The thermal and frequency dependences of the dielectric constants of both ceramics revealed relaxor behavior. The two compounds exhibited two phase transitions: ferroelectric/antiferroelectric (FE/AFE) transition followed by an antiferroelectric/paraelectric (AFE/PE) transition at higher temperatures. Remarkably, we noticed that the small amount of Gd doping (2%) highly enhanced the dielectric properties of the parent compound by about 71%. The phase diagram was as well influenced by the Gd doping, where the FE/AFE transition temperature rose from 90 in the parent compound to 115 °C in the doped one whereas the AFE/PE transition temperature was decreased from 320 to 270 °C, respectively. The direct electrocaloric measurements performed on both compounds showed that the ferroelectric/antiferroelectric phase transition was accompanied by a significant electrocaloric effect. The Gd3+ doping improved the electrocaloric properties of the parent compound, where a remarkable temperature variation of 1.4 K was obtained in the doped ceramic. The results of the direct electrocaloric measurements will be compared and discussed with those derived from the indirect method.

  5. First-principles study the elastic constant, electronic structure and thermoelectric properties of Zr1 - xHfxNiPb (x = 0, 0.25, 0.5, 0.75, 1)

    NASA Astrophysics Data System (ADS)

    Wang, Dongyang; Wang, Guangtao

    2017-02-01

    Based on first-principles calculations we systematically studied the electronic structure and thermoelectric properties of Zr1 - xHfxNiPb (x = 0, 0.25, 0.5, 0.75, 1) compounds with TB-mBJ and TB-mBJ plus spin-orbit coupling methods. Our results indicate that these compounds are thermodynamic stabled narrow-gap semiconductors. The low frequency optical branches intersect with the acoustic modes below 75cm-1 for these artificial compounds, which enhance the phonon scattering and then decrease thermal conductivity. The Hf substitution significantly decreases the lattice thermal conductivity from 13.1Wm-1K-1 (x = 0) to 0.23Wm-1K-1 (x = 0.25) at 300 K. We confirmed that the Hf doping hardly influences the power factors S2 Tσ in both of p- and n-type, but greatly decreases the thermal conductivity κ, i.e. improving the figure of merit ZT =S2 Tσ / κ. The Zr0.75Hf0.25 NiPb , Zr0.5Hf0.5 NiPb and Zr0.25Hf0.75 NiPb , with ultra low thermal conductivity (0.23, 2.2 and 0.48Wm-1K-1 at 300 K) and higher power factor, may become new candidates of high performance thermoelectric materials in both of p- and n-type.

  6. Electrical Characterization Induced by Structural Modulation in (Ca0.28Ba0.72)2.5-0.5 x (Na0.5K0.5) x Nb5O15 Ceramics

    NASA Astrophysics Data System (ADS)

    Yang, Bian; Wei, Lingling; Wang, Zhongming; Kang, Shoucheng; Chao, Xiaolian; Yang, Zupei

    2016-01-01

    (Ca0.28Ba0.72)2.5-0.5 x (Na0.5K0.5) x Nb5O15 ceramics (CBNKN, 0.0 ≤ x ≤ 0.4) with `unfilled' tungsten bronze structure were prepared by the conventional solid-state reaction method. Effects of alkalis-introducing concentration in A-sites on the microstructure, dielectric and ferroelectric properties were investigated in detail. Pure tungsten bronze structure could be obtained in all compositions according to the x-ray diffraction patterns. Raman spectroscopy results showed that co-introducing Na+ and K+ in A sites to decrease the structural vacancy could enhance the dielectric and ferroelectric properties, which was attributed to the stronger interaction inside NbO6 octahedron and large distortion degree of NbO6 polar unit. Traditional temperature dependence of dielectric characteristics and well-saturated ferroelectric hysteresis loops were observed for all CBNKN ceramics. The better comprehensive dielectric and ferroelectric properties were obtained at x = 0.2 due to the bigger distortion degree of NbO6 polar unit and the highest densification. Whereas higher alkalis-introducing concentration would deteriorate the physical and electrical properties due to the poor sintering behavior. In addition, the frequency dependence of ɛ around transition temperature ( T c) and the temperature dependence of ferroelectric properties were discussed to further clarify the relationship between composition and performance.

  7. Solid-state transformation of Fe-rich intermetallic phases in Al–5.0Cu–0.6Mn squeeze cast alloy with variable Fe contents during solution heat treatment

    SciTech Connect

    Lin, Bo; Zhang, Weiwen; Zhao, Yuliang; Li, Yuanyuan

    2015-06-15

    The Al–5.0 wt.% Cu–0.6 wt.% Mn alloys with a variable Fe content were prepared by squeeze casting. Optical microscopy (OM), Deep etching technique, scanning electron microscopy(SEM), X-ray diffraction (XRD) and transmission electron microscopy (TEM) were used to examine the solid-state transformation of Fe-rich intermetallics during the solution heat treatment. The results showed that the Chinese script-like α-Fe, Al{sub 6}(FeMn) and needle-like Al{sub 3}(FeMn) phases transform to a new Cu-rich β-Fe (Al{sub 7}Cu{sub 2}(FeMn)) phase during solution heat treatment. The possible reaction and overall transformation kinetics of the solid-state phase transformation for the Fe-rich intermetallics were investigated. - Graphical abstract: Display Omitted - Highlights: • The α-Fe, Al{sub 6}(FeMn) and Al{sub 3}(FeMn) phases change to the β-Fe phases. • Possible reactions of Fe phases during solution heat treatment are discussed. • The overall fractional transformation rate follows an Avrami curve.

  8. Thermal cycling properties of a lead-free positive temperature coefficient thermistor in the Ba0.97(Bi0.5Na0.5)0.03TiO3 system

    NASA Astrophysics Data System (ADS)

    Choi, Hyoung-Seuk; Choi, Soon-Mok; Choi, Duck-Kyun

    2016-01-01

    A Pb-free PTC (positive temperature coefficient thermistor) heater was developed in the Ba0.97(Bi0.5Na0.5)0.03TiO3 system especially for automotive part applications. The reliability was verified by using a thermal cycling test designed on the basis of the result from a quality function deployment (QFD) analysis. We compared the thermal cycling test results from the newly-developed Pb-free PTC heaters with the results from PTC heaters currently on the market, namely, PTC heaters containing Pb. Life prediction and stress-strength relationships were analyzed together with a thermal diffusivity evaluation. We discuss the potential failure mechanisms during the thermal cycling test, focusing on the fact that electrical degradation in PTC materials is closely related to mechanical degradation due to the internal stress in the materials that comes from repeated phase changes. Different grain size distributions on the sintered bulks were considered to a key factor for explaining the different results of the reliability tests between the new Pb-free PTC heaters developed in this study and the commercial PTC heaters containing Pb.

  9. DFT studies on a high-energy density cage compound 1, 3, 5, 7, 9, 11-hexo(N(CH3)NO2)-2, 4, 6, 8, 10, 12-hexaazatetracyclo[5, 5, 0, 0, 0] dodecane

    NASA Astrophysics Data System (ADS)

    Li, Xiao-Hong; Yong, Yong-Liang; Zhang, Xian-Zhou

    2014-04-01

    The infrared and Raman spectra, heat of formation (HOF) and thermodynamic properties were investigated by B3LYP/6-31G** method for a new designed polynitro cage compound 1,3,5,7,9,11-hexo(N(CH3)NO2)-2,4,6,8,10,12-hexaazatetracyclo[5,5,0,0,0]dodecane. The detonation velocity (D) and pressure (P) were predicted by the Kamlet-Jacobs equations based on the theoretical density and condensed HOF. The bond dissociation energies and bond orders for the weakest bonds were analysed to investigate the thermal stability of the title compound. The computational result shows that the detonation velocity and pressure of the title compound are superior to those of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), but inferior to those of 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane (HMX) and hexanitrohexaazaisowurtzitane (HNIW). And the analysis of thermal stability shows that the first step of pyrolysis is the rupture of the N7-NO2 bond. The crystal structure obtained by molecular mechanics belongs to the P21 space group, with the lattice parameters Z = 2, a = 11.8246 Å, b = 10.4632 Å, c = 15.9713 Å, ρ = 1.98 g cm-3.

  10. ELECTRONIC STRUCTURE AND LINEAR OPTICAL PROPERTIES OF MIXED ALKALI-METAL BOROPHOSPHATES (LiK2BP2O8, Li3K2BP4O14): A FIRST-PRINCIPLES STUDY

    NASA Astrophysics Data System (ADS)

    Zhang, Bei; Jing, Qun; Yang, Zhihua; Wang, Ying; Su, Xin; Pan, Shilie; Zhang, Jun

    2013-07-01

    LiK2BP2O8 and Li3K2BP4O14 are synthesized by high-temperature solution method with the same elements, while contain different fundamental building units. Li3K2BP4O14 is a novel P-O-P linking structure which gives a rare example of violation of Pauling's fourth rule. The electronic structures of LiK2BP2O8 and Li3K2BP4O14 are investigated by density functional calculations. Direct gaps of 5.038 eV (LiK2BP2O8) and 5.487 eV (Li3K2BP4O14) are obtained. By analyzing the density of states (DOS) of LiK2BP2O8 and Li3K2BP4O14, the P-O-P linking in fundamental building units of Li3K2BP4O14 crystal is proved theoretically. Based on the electronic properties, the linear optical information is captured.

  11. Effects of bpV(pic) and bpV(phen) on H9c2 cardiomyoblasts during both hypoxia/reoxygenation and H2O2-induced injuries.

    PubMed

    Tian, Youqing; Daoud, Abdelkader; Shang, Jing

    2012-03-01

    Reactive oxygen species (ROS) are involved in myocardial injury. ROS are known to inactivate lipid phosphatase and tension homolog on chromosome 10 (PTEN), an enzyme that increases apoptosis in neonatal cardiomyocytes. BpV(pic) and bpV(phen), two bisperoxovanadium molecules and PTEN inhibitors, may be involved in limiting myocardial infarction. To compare the protective effects of bpV(pic) and bpV(phen) on ROS-induced cardiomyocyte injury and their possible mechanisms, we selected two popular models of hypoxia/reoxygenation (H/R) and H2O2-induced injury in H9c2 cardiomyoblasts to investigate their effects against injury. We found that pre-treatment with bpV(pic) and bpV(phen) increased the viability and protected the morphology of H9c2 cells under the conditions of H/R and H2O2 by inhibiting LDH release, apoptosis and caspases 3/8/9 activities. However, their respective inhibitory abilities in the two models were different, suggesting that the quantity of ROS from the two models might be different. However, the conflict between ROS and PTEN may affect the action of bpV(pic) and bpV(phen). Taken together, the results demonstrate that bpV(pic) and bpV(phen) have inhibitory effects on oxidative stress-induced cardiomyocyte injury that may be partially modulated by the action of ROS on PTEN.

  12. Home and Online Management and Evaluation of Blood Pressure (HOME BP) digital intervention for self-management of uncontrolled, essential hypertension: a protocol for the randomised controlled HOME BP trial

    PubMed Central

    Morton, Katherine; Stuart, Beth; Raftery, James; Bradbury, Katherine; Yao, Guiqing Lily; Zhu, Shihua; Little, Paul; Yardley, Lucy

    2016-01-01

    Introduction Self-management of hypertension, including self-monitoring and antihypertensive medication titration, lowers blood pressure (BP) at 1 year compared to usual care. The aim of the current trial is to assess the effectiveness of the Home and Online Management and Evaluation of Blood Pressure (HOME BP) intervention for the self-management of hypertension in primary care. Methods and analysis The HOME BP trial will be a randomised controlled trial comparing BP self-management—consisting of the HOME BP online digital intervention with self-monitoring, lifestyle advice and antihypertensive drug titration—with usual care for people with uncontrolled essential hypertension. Eligible patients will be recruited from primary care and randomised to usual care or to self-management using HOME BP. The primary outcome will be the difference in mean systolic BP (mm Hg) at 12-month follow-up between the intervention and control groups adjusting for baseline BP and covariates. Secondary outcomes (also adjusted for baseline and covariates where appropriate) will be differences in mean BP at 6 months and diastolic BP at 12 months; patient enablement; quality of life, and economic analyses including all key resources associated with the intervention and related services, adopting a broad societal perspective to include NHS, social care and patient costs, considered within trial and modelled with a lifetime horizon. Medication beliefs, adherence and changes; self-efficacy; perceived side effects and lifestyle changes will be measured for process analyses. Qualitative analyses will explore patient and healthcare professional experiences of HOME BP to gain insights into the factors affecting acceptability, feasibility and adherence. Ethics and dissemination This study has received NHS ethical approval (REC reference 15/SC/0082). The findings from HOME BP will be disseminated widely through peer-reviewed publications, scientific conferences and workshops. If

  13. Stable semiconductor black phosphorus (BP)@titanium dioxide (TiO2) hybrid photocatalysts.

    PubMed

    Lee, Hyun Uk; Lee, Soon Chang; Won, Jonghan; Son, Byung-Chul; Choi, Saehae; Kim, Yooseok; Park, So Young; Kim, Hee-Sik; Lee, Young-Chul; Lee, Jouhahn

    2015-03-03

    Over the past few decades, two-dimensional (2D) and layered materials have emerged as new fields. Due to the zero-band-gap nature of graphene and the low photocatalytic performance of MoS2, more advanced semiconducting 2D materials have been prompted. As a result, semiconductor black phosphorus (BP) is a derived cutting-edge post-graphene contender for nanoelectrical application, because of its direct-band-gap nature. For the first time, we report on robust BP@TiO2 hybrid photocatalysts offering enhanced photocatalytic performance under light irradiation in environmental and biomedical fields, with negligible affected on temperature and pH conditions, as compared with MoS2@TiO2 prepared by the identical synthesis method. Remarkably, in contrast to pure few layered BP, which, due to its intrinsic sensitivity to oxygen and humidity was readily dissolved after just several uses, the BP@TiO2 hybrid photocatalysts showed a ~92% photocatalytic activity after 15 runs. Thus, metal-oxide-stabilized BP photocatalysts can be practically applied as a promising alternative to graphene and MoS2.

  14. Components of the CtBP1/BARS-dependent fission machinery.

    PubMed

    Valente, Carmen; Luini, Alberto; Corda, Daniela

    2013-10-01

    The brefeldin A ADP-ribosylated substrate, a member of the C-terminal-binding protein family that is referred to as CtBP1/BARS, is a dual-function protein that acts as a transcriptional co-repressor in the nucleus and as an inducer of membrane fission in the cytoplasm. In this review, we first discuss the mechanisms that enable CtBP1/BARS to shift between the nuclear transcriptional co-repressor and the cytosolic fission-inducing activities. Then, we focus on the role of CtBP1/BARS in membrane fission. CtBP1/BARS controls several fission events including macropinocytosis, fluid-phase endocytosis, COPI-coated vesicle formation, basolaterally directed post-Golgi carrier formation, and Golgi partitioning in mitosis. We report on recent advances in our understanding of the CtBP1/BARS membrane fission machineries that operate at the trans-side and at the cis-side of the Golgi complex. Specifically, we discuss how these machineries are assembled and regulated, and how they operate in the formation of the basolaterally directed post-Golgi carriers.

  15. UbcH7 regulates 53BP1 stability and DSB repair.

    PubMed

    Han, Xiangzi; Zhang, Lei; Chung, Jinsil; Mayca Pozo, Franklin; Tran, Amanda; Seachrist, Darcie D; Jacobberger, James W; Keri, Ruth A; Gilmore, Hannah; Zhang, Youwei

    2014-12-09

    DNA double-strand break (DSB) repair is not only key to genome stability but is also an important anticancer target. Through an shRNA library-based screening, we identified ubiquitin-conjugating enzyme H7 (UbcH7, also known as Ube2L3), a ubiquitin E2 enzyme, as a critical player in DSB repair. UbcH7 regulates both the steady-state and replicative stress-induced ubiquitination and proteasome-dependent degradation of the tumor suppressor p53-binding protein 1 (53BP1). Phosphorylation of 53BP1 at the N terminus is involved in the replicative stress-induced 53BP1 degradation. Depletion of UbcH7 stabilizes 53BP1, leading to inhibition of DSB end resection. Therefore, UbcH7-depleted cells display increased nonhomologous end-joining and reduced homologous recombination for DSB repair. Accordingly, UbcH7-depleted cells are sensitive to DNA damage likely because they mainly used the error-prone nonhomologous end-joining pathway to repair DSBs. Our studies reveal a novel layer of regulation of the DSB repair choice and propose an innovative approach to enhance the effect of radiotherapy or chemotherapy through stabilizing 53BP1.

  16. Determining crystal phase purity in c-BP through X-ray absorption spectroscopy.

    PubMed

    Huber, S P; Medvedev, V V; Gullikson, E; Padavala, B; Edgar, J H; van de Kruijs, R W E; Bijkerk, F; Prendergast, D

    2017-02-02

    We employ X-ray absorption near-edge spectroscopy at the boron K-edge and the phosphorus L2,3-edge to study the structural properties of cubic boron phosphide (c-BP) samples. The X-ray absorption spectra are modeled from first-principles within the density functional theory framework using the excited electron core-hole (XCH) approach. A simple structural model of a perfect c-BP crystal accurately reproduces the P L2,3-edge, however it fails to describe the broad and gradual onset of the B K-edge. Simulations of the spectroscopic signatures in boron 1s excitations of intrinsic point defects and the hexagonal BP crystal phase show that these additions to the structural model cannot reproduce the broad pre-edge of the experimental spectrum. Calculated formation enthalpies show that, during the growth of c-BP, it is possible that amorphous boron phases can be grown in conjunction with the desired boron phosphide crystalline phase. In combination with experimental and theoretically obtained X-ray absorption spectra of an amorphous boron structure, which have a similar broad absorption onset in the B K-edge spectrum as the cubic boron phosphide samples, we provide evidence for the presence of amorphous boron clusters in the synthesized c-BP samples.

  17. Mutations in TAX1BP3 cause dilated cardiomyopathy with septo-optic dysplasia.

    PubMed

    Reinstein, Eyal; Orvin, Katia; Tayeb-Fligelman, Einav; Stiebel-Kalish, Hadas; Tzur, Shay; Pimienta, Allen L; Bazak, Lily; Bengal, Tuvia; Cohen, Lior; Gaton, Dan D; Bormans, Concetta; Landau, Meytal; Kornowski, Ran; Shohat, Mordechai; Behar, Doron M

    2015-04-01

    We describe a Bedouin family with a novel autosomal recessive syndrome characterized by dilated cardiomyopathy and septo-optic dysplasia. Genetic analysis revealed a homozygous missense mutation in TAX1BP3, which encodes a small PDZ domain containing protein implicated in regulation of the Wnt/β-catenin signaling pathway, as the causative mutation. The mutation affects a conserved residue located at the core of TAX1BP3 binding pocket and is predicted to impair the nature of a crucial hydrophobic patch, thereby interrupting the structure and stability of the protein, and its ability to interact with other proteins. TAX1BP3 is highly expressed in heart and brain and consistent with the clinical findings observed in our patients; a knockdown of TAX1BP3 causes elongation defects, enlarged pericard, and enlarged head structures in zebrafish embryos. Thus, we describe a new genetic disorder that expands the monogenic cardiomyopathy disease spectrum and suggests that TAX1BP3 is essential for heart and brain development.

  18. CUG-BP1 regulates RyR1 ASI alternative splicing in skeletal muscle atrophy.

    PubMed

    Tang, Yinglong; Wang, Huiwen; Wei, Bin; Guo, Yuting; Gu, Lei; Yang, Zhiguang; Zhang, Qing; Wu, Yanyun; Yuan, Qi; Zhao, Gang; Ji, Guangju

    2015-11-04

    RNA binding protein is identified as an important mediator of aberrant alternative splicing in muscle atrophy. The altered splicing of calcium channels, such as ryanodine receptors (RyRs), plays an important role in impaired excitation-contraction (E-C) coupling in muscle atrophy; however, the regulatory mechanisms of ryanodine receptor 1 (RyR1) alternative splicing leading to skeletal muscle atrophy remains to be investigated. In this study we demonstrated that CUG binding protein 1 (CUG-BP1) was up-regulated and the alternative splicing of RyR1 ASI (exon70) was aberrant during the process of neurogenic muscle atrophy both in human patients and mouse models. The gain and loss of function experiments in vivo demonstrated that altered splicing pattern of RyR1 ASI was directly mediated by an up-regulated CUG-BP1 function. Furthermore, we found that CUG-BP1 affected the calcium release activity in single myofibers and the extent of atrophy was significantly reduced upon gene silencing of CUG-BP1 in atrophic muscle. These findings improve our understanding of calcium signaling related biological function of CUG-BP1 in muscle atrophy. Thus, we provide an intriguing perspective of involvement of mis-regulated RyR1 splicing in muscular disease.

  19. HIV-1 Vpr increases HCV replication through VprBP in cell culture.

    PubMed

    Yan, Yanling; Huang, Fang; Yuan, Ting; Sun, Binlian; Yang, Rongge

    2016-09-02

    Coinfection of human immunodeficiency virus (HIV) and hepatitis C virus (HCV) occurs at a high frequency, in which HIV shows a promotion of HCV-derived liver diseases. However, the mechanism of how this occurs is not well understood. Our previous work has demonstrated that the HIV-1 accessory protein Vpr enhances HCV RNA replication in cell culture. Because Vpr performs most of its functions through host protein VprBP (DCAF1), the role of VprBP in the regulation of HCV by Vpr was investigated in this study. We found that the Vpr mutant Q65R, which is deficient in VprBP binding, could not enhance HCV replication. Furthermore, Vpr-mediated enhancement of HCV replication was severely diminished in VprBP knockdown cells. In addition, an inhibitor of Cullin RING E3 ligases, MLN4924, impaired the function of Vpr during HCV replication. Together, these results suggest that Vpr promotes HCV replication in a VprBP-dependent manner, and that the activity of Cullin RING E3 ligases is essential to this process. In conclusion, our findings demonstrate that HIV-1 Vpr makes the cellular environment more suitable for HCV replication, which might relate with the host ubiquitination system.

  20. Evidence that mono-ADP-ribosylation of CtBP1/BARS regulates lipid storage.

    PubMed

    Bartz, René; Seemann, Joachim; Zehmer, John K; Serrero, Ginette; Chapman, Kent D; Anderson, Richard G W; Liu, Pingsheng

    2007-08-01

    Mono-ADP-ribosylation is emerging as an important posttranslational modification that modulates a variety of cell signaling pathways. Here, we present evidence that mono-ADP-ribosylation of the transcriptional corepressor C terminal binding protein, brefeldin A (BFA)-induced ADP-ribosylated substrate (CtBP1/BARS) regulates neutral lipid storage in droplets that are surrounded by a monolayer of phospholipid and associated proteins. CtBP1/BARS is an NAD-binding protein that becomes ribosylated when cells are exposed to BFA. Both endogenous lipid droplets and droplets enlarged by oleate treatment are lost after 12-h exposure to BFA. Lipid loss requires new protein synthesis, and it is blocked by multiple ribosylation inhibitors, but it is not stimulated by disruption of the Golgi apparatus or the endoplasmic reticulum unfolded protein response. Small interfering RNA knockdown of CtBP1/BARS mimics the effect of BFA, and mouse embryonic fibroblasts derived from embryos that are deficient in CtBP1/BARS seem to be defective in lipid accumulation. We conclude that mono-ADP-ribosylation of CtBP1/BARS inactivates its repressor function, which leads to the activation of genes that regulate neutral lipid storage.

  1. Neurogenesis requires TopBP1 to prevent catastrophic replicative DNA damage in early progenitors

    PubMed Central

    Lee, Youngsoo; Katyal, Sachin; Downing, Susanna M.; Zhao, Jingfeng; Russell, Helen R.; McKinnon, Peter J.

    2012-01-01

    The rapid proliferation of progenitors during neurogenesis requires a stringent genomic maintenance program to ensure transmission of genetic fidelity. However the essential factors that govern neural progenitor genome integrity are unknown. Here we report that conditional inactivation of mouse TopBP1, a protein linked to DNA replication, and a key activator of the DNA damage response kinase ATR (ataxia telangiectasia and rad3 related) is critical for maintenance of early-born neural progenitors. During cortical development TopBP1 prevented replication-associated DNA damage in Emx1-progenitors which otherwise resulted in profound tissue ablation. Importantly, disrupted neurogenesis in TopBP1-depleted tissues was substantially rescued by p53- but not ATM-inactivation. Our data establish that TopBP1 is essential for preventing replication-associated DNA strand breaks, but is not essential per se for DNA replication. Thus, TopBP1 is crucial for maintaining genome integrity in the early progenitors that drive neurogenesis. PMID:22522401

  2. Stable semiconductor black phosphorus (BP)@titanium dioxide (TiO2) hybrid photocatalysts

    PubMed Central

    Uk Lee, Hyun; Lee, Soon Chang; Won, Jonghan; Son, Byung-Chul; Choi, Saehae; Kim, Yooseok; Park, So Young; Kim, Hee-Sik; Lee, Young-Chul; Lee, Jouhahn

    2015-01-01

    Over the past few decades, two-dimensional (2D) and layered materials have emerged as new fields. Due to the zero-band-gap nature of graphene and the low photocatalytic performance of MoS2, more advanced semiconducting 2D materials have been prompted. As a result, semiconductor black phosphorus (BP) is a derived cutting-edge post-graphene contender for nanoelectrical application, because of its direct-band-gap nature. For the first time, we report on robust BP@TiO2 hybrid photocatalysts offering enhanced photocatalytic performance under light irradiation in environmental and biomedical fields, with negligible affected on temperature and pH conditions, as compared with MoS2@TiO2 prepared by the identical synthesis method. Remarkably, in contrast to pure few layered BP, which, due to its intrinsic sensitivity to oxygen and humidity was readily dissolved after just several uses, the BP@TiO2 hybrid photocatalysts showed a ~92% photocatalytic activity after 15 runs. Thus, metal-oxide-stabilized BP photocatalysts can be practically applied as a promising alternative to graphene and MoS2. PMID:25732720

  3. DNA sequence variation in BpMADS2 gene in two populations of Betula pendula.

    PubMed

    Järvinen, Pia; Lemmetyinen, Juha; Savolainen, Outi; Sopanen, Tuomas

    2003-02-01

    The PISTILLATA (PI) homologue, BpMADS2, was isolated from silver birch (Betula pendula Roth) and used to study nucleotide polymorphism. Two regions (together about 2450 bp) comprising mainly untranslated sequences were sequenced from 10 individuals from each of two populations in Finland. The nucleotide polymorphism was low in the BpMADS2 locus, especially in the coding region. The synonymous site overall nucleotide diversity (pis) was 0.0043 and the nonsynonymous nucleotide diversity (pia) was only 0.000052. For the whole region, the pi values for the two populations were 0.0039 and 0.0045, and for the coding regions, the pi values were only 0 and 0.00066 (for the corresponding coding regions of Arabidopsis thaliana PI world-wide pi was 0.0021). Estimates of pi or theta did not differ significantly between the two populations, and the two populations were not diverged from each other. Two classes of BpMADS2 alleles were present in both populations, suggesting that this gene exhibits allelic dimorphism. In addition to the nucleotide site variation, two microsatellites were also associated within the haplotypes. This allelic dimorphism might be the result of postglacial re-colonization partly from northwestern, partly from southeastern/eastern refugia. The sequence comparison detected five recombination events in the regions studied. The large number of microsatellites in all of the three introns studied suggests that BpMADS2 is a hotspot for microsatellite formation.