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Sample records for dryas cold event

  1. Multiple causes of the Younger Dryas cold period

    NARCIS (Netherlands)

    Renssen, H.; Mairesse, A.; Goosse, H.J.M.; Mathiot, P.; Heiri, O.; Roche, D.M.V.A.P.; Nisancioglu, K.H.; Valdes, P.J.

    2015-01-01

    The Younger Dryas cooling event disrupted the overall warming trend in the North Atlantic region during the last deglaciation. Climate change during the Younger Dryas was abrupt, and thus provides insights into the sensitivity of the climate system to perturbations. The sudden Younger Dryas cooling

  2. Atlantic Warm Pool Trigger for the Younger Dryas Climate Event

    Science.gov (United States)

    Abdul, N. A.; Mortlock, R. A.; Wright, J. D.; Fairbanks, R. G.; Teneva, L. T.

    2011-12-01

    There is growing evidence that variability in the size and heat content of the tropical Atlantic Warm Pool impacts circum-North Atlantic climate via the Atlantic Multi-decadal Oscillation mode (Wang et al., 2008). The Atlantic Warm Pool spans the Gulf of Mexico, Caribbean Sea and the western tropical North Atlantic. Barbados is located near the center of the tropical Atlantic Warm Pool and coupled ocean models suggest that Barbados remains near the center of the tropical Atlantic Warm Pool under varying wind stress simulations. Measurements of the oxygen isotope paleothermometer in Acropora palmata coral species recovered from cores offshore Barbados, show a 3oC monotonic decrease in sea surface temperature from 13106 ± 83 to 12744 ± 61 years before present (errors given as 2 sigma). This interval corresponds to a sea level rise from 71.4 meters to 67.1 meters below present levels at Barbados. The 3oC temperature decrease is captured in eight A. palmata specimens that are in stratigraphic sequence, 230Th/234U dated, and analyzed for oxygen isotopes. All measurements are replicated. We are confident that this is the warm pool equivalent of the Younger Dryas climate event. The initiation of this temperature drop in the Atlantic Warm Pool predates the Younger Dryas start in Greenland ice cores, reported to start at 12896 ± 138 years (relative to AD 2000) (Rasmussen et al., 2006), while few other Younger Dryas climate records are dated with similar accuracy to make the comparison. Rasmussen, S.O., Andersen, K.K., Svensson, A.M., Steffensen, J.P., Vinther, B.M., Clausen, H.B., Siggaard-Andersen, M.L., Johnsen, S.J., Larsen, L.B., Dahl-Jensen, D., Bigler, M., Röthlisberger, R., Fischer, H., Goto-Azuma, K., Hansson, M.E., and Ruth, U., 2006, A new Greenland ice core chronology for the last glacial termination: J. Geophys. Res., v. 111, p. D06102. Wang, C., Lee, S.-K., and Enfield, D.B., 2008, Atlantic Warm Pool acting as a link between Atlantic Multidecadal

  3. Minimal geological methane emissions during the Younger Dryas-Preboreal abrupt warming event.

    Science.gov (United States)

    Petrenko, Vasilii V; Smith, Andrew M; Schaefer, Hinrich; Riedel, Katja; Brook, Edward; Baggenstos, Daniel; Harth, Christina; Hua, Quan; Buizert, Christo; Schilt, Adrian; Fain, Xavier; Mitchell, Logan; Bauska, Thomas; Orsi, Anais; Weiss, Ray F; Severinghaus, Jeffrey P

    2017-08-23

    Methane (CH 4 ) is a powerful greenhouse gas and plays a key part in global atmospheric chemistry. Natural geological emissions (fossil methane vented naturally from marine and terrestrial seeps and mud volcanoes) are thought to contribute around 52 teragrams of methane per year to the global methane source, about 10 per cent of the total, but both bottom-up methods (measuring emissions) and top-down approaches (measuring atmospheric mole fractions and isotopes) for constraining these geological emissions have been associated with large uncertainties. Here we use ice core measurements to quantify the absolute amount of radiocarbon-containing methane ( 14 CH 4 ) in the past atmosphere and show that geological methane emissions were no higher than 15.4 teragrams per year (95 per cent confidence), averaged over the abrupt warming event that occurred between the Younger Dryas and Preboreal intervals, approximately 11,600 years ago. Assuming that past geological methane emissions were no lower than today, our results indicate that current estimates of today's natural geological methane emissions (about 52 teragrams per year) are too high and, by extension, that current estimates of anthropogenic fossil methane emissions are too low. Our results also improve on and confirm earlier findings that the rapid increase of about 50 per cent in mole fraction of atmospheric methane at the Younger Dryas-Preboreal event was driven by contemporaneous methane from sources such as wetlands; our findings constrain the contribution from old carbon reservoirs (marine methane hydrates, permafrost and methane trapped under ice) to 19 per cent or less (95 per cent confidence). To the extent that the characteristics of the most recent deglaciation and the Younger Dryas-Preboreal warming are comparable to those of the current anthropogenic warming, our measurements suggest that large future atmospheric releases of methane from old carbon sources are unlikely to occur.

  4. Minimal geological methane emissions during the Younger Dryas-Preboreal abrupt warming event

    Science.gov (United States)

    Petrenko, Vasilii V.; Smith, Andrew M.; Schaefer, Hinrich; Riedel, Katja; Brook, Edward; Baggenstos, Daniel; Harth, Christina; Hua, Quan; Buizert, Christo; Schilt, Adrian; Fain, Xavier; Mitchell, Logan; Bauska, Thomas; Orsi, Anais; Weiss, Ray F.; Severinghaus, Jeffrey P.

    2017-08-01

    Methane (CH4) is a powerful greenhouse gas and plays a key part in global atmospheric chemistry. Natural geological emissions (fossil methane vented naturally from marine and terrestrial seeps and mud volcanoes) are thought to contribute around 52 teragrams of methane per year to the global methane source, about 10 per cent of the total, but both bottom-up methods (measuring emissions) and top-down approaches (measuring atmospheric mole fractions and isotopes) for constraining these geological emissions have been associated with large uncertainties. Here we use ice core measurements to quantify the absolute amount of radiocarbon-containing methane (14CH4) in the past atmosphere and show that geological methane emissions were no higher than 15.4 teragrams per year (95 per cent confidence), averaged over the abrupt warming event that occurred between the Younger Dryas and Preboreal intervals, approximately 11,600 years ago. Assuming that past geological methane emissions were no lower than today, our results indicate that current estimates of today’s natural geological methane emissions (about 52 teragrams per year) are too high and, by extension, that current estimates of anthropogenic fossil methane emissions are too low. Our results also improve on and confirm earlier findings that the rapid increase of about 50 per cent in mole fraction of atmospheric methane at the Younger Dryas-Preboreal event was driven by contemporaneous methane from sources such as wetlands; our findings constrain the contribution from old carbon reservoirs (marine methane hydrates, permafrost and methane trapped under ice) to 19 per cent or less (95 per cent confidence). To the extent that the characteristics of the most recent deglaciation and the Younger Dryas-Preboreal warming are comparable to those of the current anthropogenic warming, our measurements suggest that large future atmospheric releases of methane from old carbon sources are unlikely to occur.

  5. The Case for the Younger Dryas Extraterrestrial Impact Event: Mammoth, Megafauna and Clovis Extinction

    International Nuclear Information System (INIS)

    Firestone, Richard B.

    2009-01-01

    The onset of >1000 years of Younger Dryas cooling, broad-scale extinctions, and the disappearance of the Clovis culture in North America simultaneously occurred 12,900 years ago followed immediately by the appearance of a carbon-rich black layer at many locations. In situ bones of extinct megafauna and Clovis tools occur only beneath this black layer and not within or above it. At the base of the black mat at 9 Clovis-age sites in North America and a site in Belgium numerous extraterrestrial impact markers were found including magnetic grains highly enriched in iridium, magnetic microspherules, vesicular carbon spherules enriched in cubic, hexagonal, and n-type nanodiamonds, glass-like carbon containing Fullerenes and nanodiamonds, charcoal, soot, and polycyclic aromatic hydrocarbons. The same impact markers were found mixed throughout the sediments of 15 Carolina Bays, elliptical depressions along the Atlantic coast, whose parallel major axes point towards either the Great Lakes or Hudson Bay. The magnetic grains and spherules have an unusual Fe/Ti composition similar to lunar Procellarum KREEP Terrane and the organic constituents are enriched in 14C leading to radiocarbon dates often well into the future. These characteristics are inconsistent with known meteorites and suggest that the impact was by a previous unobserved, possibly extrasolar body. The concentration of impact markers peaks near the Great Lakes and their unusually high water content suggests that a 4.6 km-wide comet fragmented and exploded over the Laurentide Ice Sheet creating numerous craters that now persist at the bottom of the Great Lakes. The coincidence of this impact, the onset of Younger Dryas cooling, extinction of the megafauna, and the appearance of a black mat strongly suggests that all these events are directly related. These results have unleashed an avalanche of controversy which I will address in this paper.

  6. Exploring the Human Ecology of the Younger Dryas Extraterrestrial Impact Event

    Science.gov (United States)

    Kennett, D. J.; Erlandson, J. M.; Braje, T. J.; Culleton, B. J.

    2007-05-01

    Several lines of evidence now exist for a major extraterrestrial impact event in North America at 12.9 ka (the YDB). This impact partially destabilized the Laurentide and Cordilleran ice sheets, triggered abrupt Younger Dryas cooling and extensive wildfires, and contributed to megafaunal extinction. This event also occurred soon after the well established colonization of the Americas by anatomically modern humans. Confirmation of this event would represent the first near-time extraterrestrial impact with significant effects on human populations. These likely included widespread, abrupt human mortality, population displacement, migration into less effected or newly established habitats, loss of cultural traditions, and resource diversification in the face of the massive megafaunal extinction and population reductions in surviving animal populations. Ultimately, these transformations established the context for the special character of plant and animal domestication and the emergence of agricultural economies in North America. We explore the Late Pleistocene archaeological record in North America within the context of documented major biotic changes associated with the YDB in North America and of the massive ecological affects hypothesized for this event.

  7. Carbon isotopes from fossil packrat pellets and elevational movements of Utah agave plants reveal the Younger Dryas cold period in Grand Canyon, Arizona

    Science.gov (United States)

    Cole, K.L.; Arundel, S.T.

    2005-01-01

    Carbon isotopes in rodent fecal pellets were measured on packrat (Neotoma spp.) middens from the Grand Canyon, Arizona. The pellet samples reflect the abundance of cold-intolerant C4 and Crassulacean acid metabolism (CAM) plant species relative to the predominant C3 vegetation in the packrat diet. The temporal sequence of isotopic results suggests a temperature decline followed by a sharp increase corresponding to the B??lling/Aller??d-Younger Dryas - early Holocene sequence. This pattern was then tested using the past distribution of Utah agave (Agave utahensis). Spatial analyses of the range of this temperature-sensitive CAM species demonstrate that its upper elevational limit is controlled by winter minimum temperature. Applying this paleotemperature proxy to the past elevational limits of Utah agave suggests that minimum winter temperatures were ???8??C below modern values during the Last Glacial Maximum, 4.5-6.5 ??C below modern during the B??lling/Aller??d, and 7.5-8.7 ??C below modern during the early Younger Dryas. As the Younger Dryas terminated, temperatures warmed ???4 ??C between ca. 11.8 ka and 11.5 ka. These extreme fluctuations in winter minimum temperature have not been generally accepted for terrestrial paleoecological records from the arid southwestern United States, likely because of large statistical uncertainties of older radiocarbon results and reliance on proxies for summer temperatures, which were less affected. ?? 2005 Geological Society of America.

  8. Cold Reversal on Kodiak Island, Alaska, Correlated with the European Younger Dryas by Using Variations of Atmospheric C-14 Content

    Science.gov (United States)

    Hajdas, Irka; Bonani, Georges; Boden, Per; Peteet, Dorothy M.; Mann, Daniel H.

    1999-01-01

    High-resolution AMS (accelerator-mass-spectrometer) radiocarbon dating was performed on late-glacial macrofossils in lake sediments from Kodiak Island, Alaska, and on shells in marine sediments from southwest Sweden. In both records, a dramatic drop in radiocarbon ages equivalent to a rise in the atmospheric C-14 by approximately 70%. coincides with the beginning of the cold period at 11000 yr B.P. (C-14 age). Thus our results show that a close correlation between climatic records around the globe is possible by using a global signature of changes in atmospheric C-14 content.

  9. The Younger Dryas climate change: was it caused by an extraterrestrial impact?

    NARCIS (Netherlands)

    van Hoesel, A.

    2014-01-01

    The Younger Dryas is an abrupt cooling event at the end of the last Glacial associated to a change in ocean circulation. According to the Younger Dryas impact hypothesis, however, one or more extraterrestrial airbursts or impacts occuring around 12.8 ka caused the Younger Dryas cooling, extensive

  10. Beringian Megafaunal Extinctions at ~37 ka B.P.: Do Micrometeorites Embedded in Fossil Tusks and Skulls Indicate an Extraterrestial Precursor to the Younger Dryas Event?

    Science.gov (United States)

    Hagstrum, J. T.; Firestone, R. B.; West, A.

    2009-12-01

    Studies of Late Pleistocene megafaunal fossils and their ancient DNA from Beringia (eastern Siberia, Alaska, and the emerged Bering Strait) indicate sharp declines in steppe bison population diversity and horse body size, extinction of the Alaskan wild ass, and local extinctions of brown bear and woolly mammoth genetic lines beginning at about 37 ka B.P. Beringia is also well known for its remarkably preserved Late Pleistocene frozen animal mummies. 14C ages of these mummies are bimodally distributed, having peaks coincident with the earlier ~37 ka B.P., and ~13 ka B.P. Younger Dryas, onset extinction events. Associated with the ~37 ka B.P. event are, for example, the Berezovka mammoth, headless Selerikan horse, steppe bison “Blue Babe”, and baby mammoths “Dima” and “Lyuba”. Analyses of these and other mummies indicate that they died instantly, in mostly healthy condition, with gut contents and high fat reserves indicative of a late summer to autumn season. An assortment of uneaten limbs and other body parts from a variety of species have also been found. Uniformitarian death scenarios inadequately account for the lack of evidence of normal predation and scavenging. Extensive internal injuries (e.g. large bone fractures, hemorrhaging) and apparent rapid burial of the mummies also indicate that something truly unusual happened at the time of these extinction events. We have discovered what appear to be micrometeorites embedded in seven Alaskan mammoth tusks and a Siberian bison skull acquired from commercial sources. 14C ages for five of these fossils have a weighted mean age of 33 ± 2 ka B.P. Laser ablation ICP-MS and XRF analyses of the particles indicate high Fe contents with compositions enriched in Ni and depleted in Ti, similar to Fe meteorites and unlike any natural terrestrial sources. Microprobe analyses of a Fe-Ni sulfide grain from tusk 2 also show that it contains between 3 and 20 weight percent Ni. SEM images and XRF analyses of a bison

  11. Differential response of vegetation in Hulun Lake region at the northern margin of Asian summer monsoon to extreme cold events of the last deglaciation

    Science.gov (United States)

    Zhang, Shengrui; Xiao, Jule; Xu, Qinghai; Wen, Ruilin; Fan, Jiawei; Huang, Yun; Yamagata, Hideki

    2018-06-01

    The response of vegetation to extreme cold events during the last deglaciation is important for assessing the impact of possible extreme climatic events on terrestrial ecosystems under future global warming scenarios. Here, we present a detailed record of the development of regional vegetation in the northern margin of Asian summer monsoon during the last deglaciation (16,500-11,000 cal yr BP) based on a radiocarbon-dated high-resolution pollen record from Hulun Lake, northeast China. The results show that the regional vegetation changed from subalpine meadow-desert steppe to mixed coniferous and deciduous forest-typical steppe during the last deglaciation. However, its responses to the Heinrich event 1 (H1) and the Younger Dryas event (YD) were significantly different: during the H1 event, scattered sparse forest was present in the surrounding mountains, while within the lake catchment the vegetation cover was poor and was dominated by desert steppe. In contrast, during the YD event, deciduous forest developed and the proportion of coniferous forest increased in the mountains, the lake catchment was occupied by typical steppe. We suggest that changes in Northern Hemisphere summer insolation and land surface conditions (ice sheets and sea level) caused temperature and monsoonal precipitation variations that contributed to the contrasting vegetation response during the two cold events. We conclude that under future global warming scenarios, extreme climatic events may cause a deterioration of the ecological environment of the Hulun Lake region, resulting in increased coniferous forest and decreased total forest cover in the surrounding mountains, and a reduction in typical steppe in the lake catchment.

  12. Detailed Tropical Sea Level Record Spanning the Younger Dryas Chronozone

    Science.gov (United States)

    Abdul, N. A.; Mortlock, R. A.; Wright, J. D.; Fairbanks, R. G.

    2010-12-01

    Variability in sea level is a fundamental measure of past changes in continental ice volume and provides an important benchmark to test climate change hypotheses. Records of the most recent deglaciation show two pulses of accelerated sea-level rise (Meltwater Pulses 1A and 1B) separated by an interval of slower sea level rise. The Younger Dryas chronozone falls within the interval between MWP 1A and 1B. It was first described over 100 years ago and remains one of the most studied periods in Earth’s history. The Younger Dryas was originally constrained with 14C dating to the interval between 11,000 and 10,000 14C years BP, which converts to 13,000 to 11,640 calendar years BP. The climatic expression of the Younger Dryas was most pronounced in the circum North Atlantic where climate proxies returned in some regions to near glacial values. Interpretations of the Younger Dryas’ significance range from a catastrophic global cooling event accompanied by Northern hemisphere ice sheet growth to simply regional changes in ocean and air mass mixing zones confined mainly to the North Atlantic. A detailed sea level record containing the interval from the end of MWP 1A to the beginning of MWP 1B (~14,000 to 11,300 years BP) was generated using 26 new U/Th dates from our 2007 Barbados offshore drilling expedition combined with our 1988 expedition measurements. 16 of these dates fall within the Younger Dryas Chronozone. Younger Dryas sea level positions were based on Acropora palmata samples from 3 overlapping and contemporaneous offshore drill cores (RGF 12 and BBDS 9 & 10) and corrected for minor tectonic uplift. From 14,000 to 11,300 years BP, sea level rose from ~81 to 56.5 m below present sea level with an initial rate of 10 m/kyr that decreased smoothly to <5 m/kyr at the base of MWP 1B. At the beginning of the Younger Dryas, sea level was at 69 m below present and rose 8 m by the end of this interval. In the context of the Barbados sea level record, the Younger Dryas

  13. Modeling a cold-air drainage event with a wireless sensor network

    OpenAIRE

    Brian R. Zutta; Eric A. Graham; Philip W. Rundel

    2005-01-01

    A wireless network of sensors was used to characterize a cold-air drainage event in the canyon surrounding the James Reserve. The flow of cold air at night and the first hours of sunrise have major ecological consequences by limiting the vegetation types to those tolerant of freeze and thaw cycles. A network of wireless sensors provides the opportunity to track this event in real time and fully characterize the cold air flow down the canyon, which may last 1.5 hours, and the pooling of cold a...

  14. Analysis of the Younger Dryas Impact Layer

    Energy Technology Data Exchange (ETDEWEB)

    Firestone, Richard B.; West, Allen; Revay, Zsolt; Hagstrum, Jonathon T,; Belgya, Thomas; Hee, Shane S. Que; Smith, Alan R.

    2010-02-27

    We have uncovered a thin layer of magnetic grains and microspherules, carbon spherules, and glass-like carbon at nine sites across North America, a site in Belgium, and throughout the rims of 16 Carolina Bays. It is consistent with the ejecta layer from an impact event and has been dated to 12.9 ka BP coinciding with the onset of Younger Dryas (YD) cooling and widespread megafaunal extinctions in North America. At many locations the impact layer is directly below a black mat marking the sudden disappearance of the megafauna and Clovis people. The distribution pattern of the Younger Dryas boundary (YDB) ejecta layer is consistent with an impact near the Great Lakes that deposited terrestrial-like ejecta near the impact site and unusual, titanium-rich projectile-like ejecta further away. High water content associated with the ejecta, up to 28 at. percent hydrogen (H), suggests the impact occurred over the Laurentide Ice Sheet. YDB microspherules and magnetic grains are highly enriched in TiO{sub 2}. Magnetic grains from several sites are enriched in iridium (Ir), up to 117 ppb. The TiO{sub 2}/FeO, K/Th, TiO{sub 2}/Zr, Al{sub 2}O{sub 3}/FeO+MgO, CaO/Al{sub 2}O{sub 3}, REE/ chondrite, FeO/MnO ratios and SiO{sub 2}, Na{sub 2}O, K{sub 2}O, Cr{sub 2}O{sub 3}, Ni, Co, U, Th and other trace element abundances are inconsistent with all terrestrial and extraterrestrial (ET) sources except for KREEP, a lunar igneous rock rich in potassium (K), rare-earth elements (REE), phosphorus (P), and other incompatible elements including U and Th. Normal Fe, Ti, and {sup 238}U/{sup 235}U isotopic abundances were found in the magnetic grains, but {sup 234}U was enriched over equilibrium values by 50 percent in Murray Springs and by 130 percent in Belgium. 40K abundance is enriched by up to 100 percent in YDB sediments and Clovis chert artifacts. Highly vesicular carbon spherules containing nanodiamonds, glass-like carbon, charcoal and soot found in large quantities in the YDB layer are

  15. Relative contributions of synoptic and intraseasonal variations to strong cold events over eastern China

    Science.gov (United States)

    Song, Lei; Wu, Renguang; Jiao, Yang

    2018-06-01

    The present study investigates the relative roles of intraseasonal oscillations (ISOs) and synoptic variations in strong cold events over eastern China during the boreal winter. The ISOs and synoptic variations explain about 55% and 20% of the total area-mean temperature anomaly in eastern China, respectively. The advection of synoptic winds on synoptic temperature gradients has a leading contribution to the temperature decrease before the cold events and thus the synoptic variations are important in determining the time of peak cold anomalies. The ISOs have a larger role in sustaining the cold events. The height anomalies associated with ISOs and synoptic variations are manifested as Rossby wave trains propagating along the polar front jet over the Eurasian continent before the cold events. They both contribute to the deepening of the East Asian trough and the development of cold events. Compared to the ISO wave train, the synoptic wave train has a smaller spatial scale and moves faster. There are obvious intraseasonal signals in the stratosphere about 1 week before the cold events over eastern China. Large negative height anomalies associated with the weakening of the polar vortex are observed over the North Atlantic. These anomalies move eastwards and propagate downwards after reaching the west coast of Europe. The downward moving stratospheric signal triggers height anomalies in the troposphere over the entrance region of the polar front jet. Then the anomalies propagate towards East Asia along the wave train, contributing to the intensification of the Siberian high and the East Asian trough and the occurrence of cold events over eastern China.

  16. Numerical Modeling of the Severe Cold Weather Event over Central Europe (January 2006

    Directory of Open Access Journals (Sweden)

    D. Hari Prasad

    2010-01-01

    Full Text Available Cold waves commonly occur in higher latitudes under prevailing high pressure systems especially during winter season which cause serious economical loss and cold related death. Accurate prediction of such severe weather events is important for decision making by administrators and for mitigation planning. An Advanced high resolution Weather Research and Forecasting mesoscale model is used to simulate a severe cold wave event occurred during January 2006 over Europe. The model is integrated for 31 days starting from 00UTC of 1 January 2006 with 30 km horizontal resolution. Comparison of the model derived area averaged daily mean temperatures at 2m height from different zones over the central Europe with observations indicates that the model is able to simulate the occurrence of the cold wave with the observed time lag of 1 to 3days but with lesser intensity. The temperature, winds, surface pressure and the geopential heights at 500 hPa reveal that the cold wave development associates with the southward progression of a high pressure system and cold air advection. The results have good agreement with the analysis fields indicates that the model has the ability to reproduce the time evolution of the cold wave event.

  17. Reduced solar activity as a trigger for the start of the Younger Dryas?

    NARCIS (Netherlands)

    Renssen, H; van Geel, B; van der Plicht, J; Magny, M

    2000-01-01

    It is generally assumed that changes in ocean circulation forced the abrupt climate changes during the Late Pleistocene, including the Younger Dryas event. Recently, however, it was proposed that variations in solar irradiance could have played a much more prominent role in forcing Pleistocene

  18. Medieval Irish chronicles reveal persistent volcanic forcing of severe winter cold events, 431–1649 CE

    International Nuclear Information System (INIS)

    Ludlow, Francis; Stine, Alexander R; Leahy, Paul; Kiely, Gerard; Murphy, Enda; Mayewski, Paul A; Taylor, David; Killen, James; Hennessy, Mark; Baillie, Michael G L

    2013-01-01

    Explosive volcanism resulting in stratospheric injection of sulfate aerosol is a major driver of regional to global climatic variability on interannual and longer timescales. However, much of our knowledge of the climatic impact of volcanism derives from the limited number of eruptions that have occurred in the modern period during which meteorological instrumental records are available. We present a uniquely long historical record of severe short-term cold events from Irish chronicles, 431–1649 CE, and test the association between cold event occurrence and explosive volcanism. Thirty eight (79%) of 48 volcanic events identified in the sulfate deposition record of the Greenland Ice Sheet Project 2 ice-core correspond to 37 (54%) of 69 cold events in this 1219 year period. We show this association to be statistically significant at the 99.7% confidence level, revealing both the consistency of response to explosive volcanism for Ireland’s climatically sensitive Northeast Atlantic location and the large proportional contribution of volcanism to historic cold event frequencies here. Our results expose, moreover, the extent to which volcanism has impacted winter-season climate for the region, and can help to further resolve the complex spatial patterns of Northern Hemisphere winter-season cooling versus warming after major eruptions. (letter)

  19. The Younger Dryas age of the Salpausselkä moraines in Finland

    Directory of Open Access Journals (Sweden)

    Joakim Donner

    2010-12-01

    Full Text Available The late-glacial Younger Dryas Stadial, as defined over seventy years ago in Denmark, was compared with the withdrawal of the Scandinavian ice sheet and correlated in Finland in 1951 with the formation of the Salpausselkä moraines. Since then a great number of studies of Younger Dryas has eventually led to its definition in the Event Stratigraphy for the North Atlantic region, based on the oxygen isotope stratigraphy in the Greenland ice-core NGRIP. The age of the Younger Dryas / Preboreal boundary, the beginning of the Holocene, is in this stratigraphy dated at 11 653 yr. BP, an age close to the age deter-mined for the drainage of the Baltic Ice Lake and the beginning of the rapid retreat of the ice margin from Salpausselkä II in Finland and the corresponding Billingen moraine in Sweden. This leads to the conclusion that the Salpausselkä moraines Ss I and Ss II were formed during Younger Dryas, according to the revised varve chronology between c. 12 260 and c. 11 600 yr. BP. The third Salpausselkä, Ss III, was according to this dating formed in early Holocene. After the 1950s, when the Salpausselkä moraines were dated as having been formed during the Younger Dryas Stadial, the ages of the boundaries of Younger Dryas changed as a result of revisions of the time scales of varved clays and the use of radiocarbon ages and their calibrations. As a result of these changes the age of the two main Salpausselkä moraines, Ss I and Ss II, is older than assumed 60 years ago on the basis of the varve chronology.

  20. A Younger Dryas re-advance of local glaciers in north Greenland

    DEFF Research Database (Denmark)

    Larsen, Nicolaj K.; Funder, Svend; Linge, Henriette

    2016-01-01

    The Younger Dryas (YD) is a well-constrained cold event from 12,900 to 11,700 years ago but it remains unclear how the cooling and subsequent abrupt warming recorded in ice cores was translated into ice margin fluctuations in Greenland. Here we present 10Be surface exposure ages from three moraines...... in front of local glaciers on a 50 km stretch along the north coast of Greenland, facing the Arctic Ocean. Ten ages range from 11.6 ± 0.5 to 27.2 ± 0.9 ka with a mean age of 12.5 ± 0.7 ka after exclusion of two outliers. We consider this to be a minimum age for the abandonment of the moraines. The ages...... the interval 11.8-13.0 ka ago. This is the first time a synchronous YD glacier advance and subsequent retreat has been recorded for several independent glaciers in Greenland. In most other areas, there is no evidence for re-advance and glaciers were retreating during YD. We explain the different behaviour...

  1. Post-Younger Dryas climate interval linked to circumpolar vortex variability: isotopic evidence from Fayetteville Green Lake, New York

    Science.gov (United States)

    Kirby, M. E.; Patterson, W. P.; Mullins, H. T.; Burnett, A. W.

    2002-04-01

    The late-Glacial/Holocene transition in the North Atlantic-European sectors has long been known to be a period of rapid climate change. There is, however, a continued need for acquiring and developing paleoclimate archives spanning this interval from continental settings. Here we report on a lacustrine (Fayetteville Green Lake) isotope record sampled at a 10-year resolution from the NE USA over the late-Glacial/Holocene interval (14,600-8000 cal year BP). Based on prior isotopic and hydrologic research from Green Lake, the δ18O(calcite) values predominantly reflect winter moisture source and thus winter atmospheric patterns. Furthermore, we use historic (AD 1948-1980) winter circulation data and δ18O(calcite) values from varved sediments to examine the relationship between the circumpolar vortex latitude and isotopes which results in a strong (r = -0.79 r2 = 0.63) negative relationship. Using the linear regression from the isotope-vortex relationship, we model the winter vortex latitude for the late-Glacial/Holocene transition over the NE USA. In addition, we identify an interval from 11,600 to 10,300 cal year BP (the post-Younger Dryas climate interval) wherein the mean winter vortex over the NE USA was expanded by 6° latitude ( 36.1°N i.e., 630 km) from its mean historic position between AD 1948-1998 ( 41.8°N). Renewal of more vigorous thermohaline circulation following the Younger Dryas cold event may have forced the post-Younger Dryas climate interval. Increased poleward heat transport due to an active oceanic conveyor would have strengthened the thermal contrast between the NE USA and the North Atlantic thereby enhancing atmospheric pressure gradients and firmly establishing the semi-permanent winter trough over the NE USA. Consequently, storms tracked more frequently up the east coast of the United States from the Gulf of Mexico and Atlantic regions delivering precipitation with relatively high δ18O values to the NE USA. Alternatively, the relative

  2. The Younger Dryas impact hypothesis: A requiem

    Science.gov (United States)

    Pinter, Nicholas; Scott, Andrew C.; Daulton, Tyrone L.; Podoll, Andrew; Koeberl, Christian; Anderson, R. Scott; Ishman, Scott E.

    2011-06-01

    The Younger Dryas (YD) impact hypothesis is a recent theory that suggests that a cometary or meteoritic body or bodies hit and/or exploded over North America 12,900 years ago, causing the YD climate episode, extinction of Pleistocene megafauna, demise of the Clovis archeological culture, and a range of other effects. Since gaining widespread attention in 2007, substantial research has focused on testing the 12 main signatures presented as evidence of a catastrophic extraterrestrial event 12,900 years ago. Here we present a review of the impact hypothesis, including its evolution and current variants, and of efforts to test and corroborate the hypothesis. The physical evidence interpreted as signatures of an impact event can be separated into two groups. The first group consists of evidence that has been largely rejected by the scientific community and is no longer in widespread discussion, including: particle tracks in archeological chert; magnetic nodules in Pleistocene bones; impact origin of the Carolina Bays; and elevated concentrations of radioactivity, iridium, and fullerenes enriched in 3He. The second group consists of evidence that has been active in recent research and discussions: carbon spheres and elongates, magnetic grains and magnetic spherules, byproducts of catastrophic wildfire, and nanodiamonds. Over time, however, these signatures have also seen contrary evidence rather than support. Recent studies have shown that carbon spheres and elongates do not represent extraterrestrial carbon nor impact-induced megafires, but are indistinguishable from fungal sclerotia and arthropod fecal material that are a small but common component of many terrestrial deposits. Magnetic grains and spherules are heterogeneously distributed in sediments, but reported measurements of unique peaks in concentrations at the YD onset have yet to be reproduced. The magnetic grains are certainly just iron-rich detrital grains, whereas reported YD magnetic spherules are

  3. Potential applications of heat and cold stress indices to sporting events.

    Science.gov (United States)

    Moran, D S

    2001-01-01

    Many recreational and elite athletes participate in sporting events every year. However, when these events are conducted under hostile environmental conditions, whether in cold or hot climates, the risk for environmental illnesses increases. The higher the stress, the greater is the potential for performance decrements, injuries and illnesses. The most common expected heat illnesses are heat exhaustion and heatstroke, whereas hypothermia and frostbite are the most common cold injuries. However, heat and cold stress indices can minimise the risk for environmental illnesses and dehydration by following the recommendations and guidelines which accompany these indices. Stress indices should be used by athletes, coaches and officials to prevent injury and improve safety conditions for competitors and participants in recreational activities. All participants should be made aware of warning signs, susceptibility and predisposing conditions. Coaches should be aware of their responsibility with regard to the safety of their trainees, and officials should organise and plan events at times that are likely to be of low environmental stress. However, they must also be prepared and equipped with the means necessary to reduce injuries and treat cases of collapse and environmental illnesses. The lack of a friendly, small and simple device for environmental stress assessment is probably the main reason why stress indices are not commonly used. We believe that developing a new portable heat and cold stress monitor in wristwatch format for use by those exposed to environmental stress could help in the decision making process of expected hazards caused by exercising and working in hostile environments, and might help prevent heat and cold illnesses.

  4. Weakened cyclones, intensified anticyclones and recent extreme cold winter weather events in Eurasia

    International Nuclear Information System (INIS)

    Zhang Xiangdong; Lu Chuhan; Guan Zhaoyong

    2012-01-01

    Extreme cold winter weather events over Eurasia have occurred more frequently in recent years in spite of a warming global climate. To gain further insight into this regional mismatch with the global mean warming trend, we analyzed winter cyclone and anticyclone activities, and their interplay with the regional atmospheric circulation pattern characterized by the semi-permanent Siberian high. We found a persistent weakening of both cyclones and anticyclones between the 1990s and early 2000s, and a pronounced intensification of anticyclone activity afterwards. It is suggested that this intensified anticyclone activity drives the substantially strengthening and northwestward shifting/expanding Siberian high, and explains the decreased midlatitude Eurasian surface air temperature and the increased frequency of cold weather events. The weakened tropospheric midlatitude westerlies in the context of the intensified anticyclones would reduce the eastward propagation speed of Rossby waves, favoring persistence and further intensification of surface anticyclone systems. (letter)

  5. The Younger Dryas impact hypothesis: A critical review

    NARCIS (Netherlands)

    van Hoesel, A.; Hoek, W.Z.; Pennock, G.M.; Drury, Martyn

    2014-01-01

    The Younger Dryas impact hypothesis suggests that multiple extraterrestrial airbursts or impacts resulted in the Younger Dryas cooling, extensive wildfires, megafaunal extinctions and changes in human population. After the hypothesis was first published in 2007, it gained much criticism, as the

  6. A Younger Dryas re-advance of local glaciers in north Greenland

    Science.gov (United States)

    Larsen, Nicolaj K.; Funder, Svend; Linge, Henriette; Möller, Per; Schomacker, Anders; Fabel, Derek; Xu, Sheng; Kjær, Kurt H.

    2016-09-01

    The Younger Dryas (YD) is a well-constrained cold event from 12,900 to 11,700 years ago but it remains unclear how the cooling and subsequent abrupt warming recorded in ice cores was translated into ice margin fluctuations in Greenland. Here we present 10Be surface exposure ages from three moraines in front of local glaciers on a 50 km stretch along the north coast of Greenland, facing the Arctic Ocean. Ten ages range from 11.6 ± 0.5 to 27.2 ± 0.9 ka with a mean age of 12.5 ± 0.7 ka after exclusion of two outliers. We consider this to be a minimum age for the abandonment of the moraines. The ages of the moraines are furthermore constrained using Optically Stimulated Luminescence (OSL) dating of epishelf sediments, which were deposited prior to the ice advance that formed the moraines, yielding a maximum age of 12.4 ± 0.6 ka, and bracketing the formation and subsequent abandonment of the moraines to within the interval 11.8-13.0 ka ago. This is the first time a synchronous YD glacier advance and subsequent retreat has been recorded for several independent glaciers in Greenland. In most other areas, there is no evidence for re-advance and glaciers were retreating during YD. We explain the different behaviour of the glaciers in northernmost Greenland as a function of their remoteness from the Atlantic Meridional Overturning Circulation (AMOC), which in other areas has been held responsible for modifying the YD drop in temperatures.

  7. Heterologous microarray experiments allow the identification of the early events associated with potato tuber cold sweetening

    Directory of Open Access Journals (Sweden)

    Vitulli Federico

    2008-04-01

    Full Text Available Abstract Background Since its discovery more than 100 years ago, potato (Solanum tuberosum tuber cold-induced sweetening (CIS has been extensively investigated. Several carbohydrate-associated genes would seem to be involved in the process. However, many uncertainties still exist, as the relative contribution of each gene to the process is often unclear, possibly as the consequence of the heterogeneity of experimental systems. Some enzymes associated with CIS, such as β-amylases and invertases, have still to be identified at a sequence level. In addition, little is known about the early events that trigger CIS and on the involvement/association with CIS of genes different from carbohydrate-associated genes. Many of these uncertainties could be resolved by profiling experiments, but no GeneChip is available for the potato, and the production of the potato cDNA spotted array (TIGR has recently been discontinued. In order to obtain an overall picture of early transcriptional events associated with CIS, we investigated whether the commercially-available tomato Affymetrix GeneChip could be used to identify which potato cold-responsive gene family members should be further studied in detail by Real-Time (RT-PCR (qPCR. Results A tomato-potato Global Match File was generated for the interpretation of various aspects of the heterologous dataset, including the retrieval of best matching potato counterparts and annotation, and the establishment of a core set of highly homologous genes. Several cold-responsive genes were identified, and their expression pattern was studied in detail by qPCR over 26 days. We detected biphasic behaviour of mRNA accumulation for carbohydrate-associated genes and our combined GeneChip-qPCR data identified, at a sequence level, enzymatic activities such as β-amylases and invertases previously reported as being involved in CIS. The GeneChip data also unveiled important processes accompanying CIS, such as the induction of redox

  8. Cold fronts in the Colombian Caribbean Sea and their relationship to extreme wave events

    Science.gov (United States)

    Ortiz-Royero, J. C.; Otero, L. J.; Restrepo, J. C.; Ruiz, J.; Cadena, M.

    2013-11-01

    Extreme ocean waves in the Caribbean Sea are commonly related to the effects of storms and hurricanes during the months of June through November. The collapse of 200 m of the Puerto Colombia pier in March 2009 revealed the effects of meteorological phenomena other than storms and hurricanes that may be influencing the extreme wave regime in the Colombian Caribbean. The marked seasonality of these atmospheric fronts was established by analyzing the meteorological-marine reports of the Instituto de Hidrología, Meteorología y Estudios Ambientales of Colombia (IDEAM, based on its initials in Spanish) and the Centro de Investigación en Oceanografía y Meteorología of Colombia (CIOH, based on its initials in Spanish) during the last 16 yr. The highest number of cold fronts was observed during the months of January, February, and March, with 6 fronts occurring per year. An annual trend was observed and the highest number of fronts occurred in 2010 (20 in total); moreover, an annual strong relationship between the maximum average wave values and the cold fronts in the central zone of the Colombian Caribbean during the first three months of the year was established. In addition, the maximum values of the significant height produced by the passage of cold fronts during the last 16 yr were identified. Although the Colombian Caribbean has been affected by storms and hurricanes in the past, this research allows us to conclude that there is a strong relationship between cold fronts and the largest waves in the Colombian Caribbean during the last 16 yr, which have caused damage to coastal infrastructure. We verified that the passage of a cold front corresponded to the most significant extreme wave event of the last two decades in the Colombian Caribbean, which caused the structural collapse of the Puerto Colombia pier, located near the city of Barranquilla, between 5 and 10 March 2009. This information is invaluable when evaluating average and extreme wave regimes for the

  9. Younger Dryas sea level and meltwater pulse 1B recorded in Barbados reef crest coral Acropora palmata

    Science.gov (United States)

    Abdul, N. A.; Mortlock, R. A.; Wright, J. D.; Fairbanks, R. G.

    2016-02-01

    The Younger Dryas climate event occurred during the middle of the last deglacial cycle and is marked by an abrupt shift in the North Atlantic polar front almost to its former glacial position, trending east to west. Using high-precision and high-accuracy U-Th-dated Barbados reef crest coral, Acropora palmata, we generate a detailed sea level record from 13.9 to 9000 years before present (kyr B.P.) and reconstruct the ice volume response to the Younger Dryas cooling. From the mid-Allerød (13.9 kyr B.P.) to the end of the Younger Dryas (11.65 kyr B.P.), rates of sea level rise decreased smoothly from 20 mm yr-1 to 4 mm yr-1, culminating in a 400 year "slow stand" before accelerating into meltwater pulse 1B (MWP-1B). The MWP-1B event at Barbados is better constrained as beginning by 11.45 kyr B.P. and ending at 11.1 kyr B.P. during which time sea level rose 14 ± 2 m and rates of sea level rise reached 40 mm yr-1. We propose that MWP-1B is the direct albeit lagged response of the Northern Hemisphere ice sheets to the rapid warming marking the end of the Younger Dryas coinciding with rapid warming in the circum-North Atlantic region and the polar front shift from its zonal to meridional position 11.65 kyr B.P. As predicted by glaciological models, the ice sheet response to rapid North Atlantic warming was lagged by 400 years due to the thermal inertia of large ice sheets. The regional circum-North Atlantic Younger Dryas climate event is elevated to a global response through sea level changes, starting with the global slowdown in sea level rise during the Younger Dryas and culminating with MWP-1B. No meltwater pulses are evident at the initiation of the Younger Dryas climate event as is often speculated.

  10. Rapid continental-scale vegetation response to the Younger Dryas Cool Episode

    Science.gov (United States)

    Peros, M.; Gajewski, K.; Viau, A.

    2006-12-01

    The Younger Dryas Cool Episode had rapid and widespread effects on flora and fauna throughout the Americas. Fossil pollen records document how plant communities responded to this event, although such data are generally only representative of changes at local- to regional-scales. We use a new approach to provide insight into vegetation responses to the Younger Dryas at a continental-scale, by focusing on data extracted for a single taxon (Populus poplar, cottonwood, aspen) from pollen diagrams throughout North America. We show that Populus underwent a rapid and continent-wide decline as the climate rapidly cooled and dried. At the termination of the Younger Dryas, Populus underwent another widespread decline, this time in response to competition from boreal and temperate taxa as the climate abruptly warmed. Late glacial-early Holocene pollen assemblages with high quantities of Populus pollen often lack modern analogues and thus confound quantitative paleoclimatic reconstructions; our results provide a context to interpret these assemblages. Furthermore, while Populus may continue to expand in the future in response to human disturbance and increasing temperatures, its sensitivity to competition may eventually put it at risk as global warming accelerates.

  11. NETmundial: only a landmark event if 'Digital Cold War' rhetoric abandoned

    Directory of Open Access Journals (Sweden)

    Francesca Musiani

    2014-03-01

    Full Text Available While internet privacy has been a central concern for quite a long time, the revelations by Edward Snowden about the US National Security Agency’s massive surveillance programme have highlighted the extent to which it is a core political issue. The privacy-surveillance controversy has prompted what is perhaps the most prominent and ambitious call in internet governance history to break the dominance of the United States' control over internet infrastructure: the Global Multistakeholder Meeting on the Future of Internet Governance, or NETmundial (April 2014. The article analyses the current state of multi-stakeholderism in internet governance in light of this event. In particular, it argues for the necessity to leave the ‘Digital Cold War’ rhetoric behind if the internationalisation and the globalisation of internet governance is to move to the next level.

  12. Adverse events associated with opioid-containing cough and cold medications in children.

    Science.gov (United States)

    Paul, Ian M; Reynolds, Kate M; Green, Jody L

    2018-04-10

    Until recently most of the scrutiny of opioid-containing cough and cold medications (CCMs) by the US Food and Drug Administration (FDA) was focused on codeine, only recently shifting equal focus to those containing hydrocodone. We characterized adverse events (AEs) in children Dictionary for Regulatory Activities with preferred terms reported. One hundred and fourteen of the 7035 (2%) cases reviewed involved an opioid-containing product. Ninety-eight cases involved an AE at least potentially related to the opioid ingredient (38 (39%) codeine; 60 (61%) hydrocodone). All three fatality cases involved hydrocodone with an antihistamine. Among non-fatalities, somnolence, lethargy, and/or respiratory depression were more commonly reported among hydrocodone cases than codeine cases (86% vs. 61%; p = .005). These safety surveillance data support the FDA's expanded label changes limiting opioid CCMs for children.

  13. A Blind Test of the Younger Dryas Impact Hypothesis.

    Directory of Open Access Journals (Sweden)

    Vance Holliday

    Full Text Available The Younger Dryas Impact Hypothesis (YDIH states that North America was devastated by some sort of extraterrestrial event ~12,800 calendar years before present. Two fundamental questions persist in the debate over the YDIH: Can the results of analyses for purported impact indicators be reproduced? And are the indicators unique to the lower YD boundary (YDB, i.e., ~12.8k cal yrs BP? A test reported here presents the results of analyses that address these questions. Two different labs analyzed identical splits of samples collected at, above, and below the ~12.8ka zone at the Lubbock Lake archaeological site (LL in northwest Texas. Both labs reported similar variation in levels of magnetic micrograins (>300 mg/kg >12.8ka and <11.5ka, but <150 mg/kg 12.8ka to 11.5ka. Analysis for magnetic microspheres in one split, reported elsewhere, produced very low to nonexistent levels throughout the section. In the other split, reported here, the levels of magnetic microspherules and nanodiamonds are low or nonexistent at, below, and above the YDB with the notable exception of a sample <11,500 cal years old. In that sample the claimed impact proxies were recovered at abundances two to four orders of magnitude above that from the other samples. Reproducibility of at least some analyses are problematic. In particular, no standard criteria exist for identification of magnetic spheres. Moreover, the purported impact proxies are not unique to the YDB.

  14. Younger Dryas cooling and the Greenland climate response to CO2.

    Science.gov (United States)

    Liu, Zhengyu; Carlson, Anders E; He, Feng; Brady, Esther C; Otto-Bliesner, Bette L; Briegleb, Bruce P; Wehrenberg, Mark; Clark, Peter U; Wu, Shu; Cheng, Jun; Zhang, Jiaxu; Noone, David; Zhu, Jiang

    2012-07-10

    Greenland ice-core δ(18)O-temperature reconstructions suggest a dramatic cooling during the Younger Dryas (YD; 12.9-11.7 ka), with temperatures being as cold as the earlier Oldest Dryas (OD; 18.0-14.6 ka) despite an approximately 50 ppm rise in atmospheric CO(2). Such YD cooling implies a muted Greenland climate response to atmospheric CO(2), contrary to physical predictions of an enhanced high-latitude response to future increases in CO(2). Here we show that North Atlantic sea surface temperature reconstructions as well as transient climate model simulations suggest that the YD over Greenland should be substantially warmer than the OD by approximately 5 °C in response to increased atmospheric CO(2). Additional experiments with an isotope-enabled model suggest that the apparent YD temperature reconstruction derived from the ice-core δ(18)O record is likely an artifact of an altered temperature-δ(18)O relationship due to changing deglacial atmospheric circulation. Our results thus suggest that Greenland climate was warmer during the YD relative to the OD in response to rising atmospheric CO(2), consistent with sea surface temperature reconstructions and physical predictions, and has a sensitivity approximately twice that found in climate models for current climate due to an enhanced albedo feedback during the last deglaciation.

  15. Bayesian chronological analyses consistent with synchronous age of 12,835–12,735 Cal B.P. for Younger Dryas boundary on four continents

    Science.gov (United States)

    Kennett, James P.; Kennett, Douglas J.; Culleton, Brendan J.; Aura Tortosa, J. Emili; Bischoff, James L.; Bunch, Ted E.; Daniel, I. Randolph; Erlandson, Jon M.; Ferraro, David; Firestone, Richard B.; Goodyear, Albert C.; Israde-Alcántara, Isabel; Johnson, John R.; Jordá Pardo, Jesús F.; Kimbel, David R.; LeCompte, Malcolm A.; Lopinot, Neal H.; Mahaney, William C.; Moore, Andrew M. T.; Moore, Christopher R.; Ray, Jack H.; Stafford, Thomas W.; Tankersley, Kenneth Barnett; Wittke, James H.; Wolbach, Wendy S.; West, Allen

    2015-01-01

    The Younger Dryas impact hypothesis posits that a cosmic impact across much of the Northern Hemisphere deposited the Younger Dryas boundary (YDB) layer, containing peak abundances in a variable assemblage of proxies, including magnetic and glassy impact-related spherules, high-temperature minerals and melt glass, nanodiamonds, carbon spherules, aciniform carbon, platinum, and osmium. Bayesian chronological modeling was applied to 354 dates from 23 stratigraphic sections in 12 countries on four continents to establish a modeled YDB age range for this event of 12,835–12,735 Cal B.P. at 95% probability. This range overlaps that of a peak in extraterrestrial platinum in the Greenland Ice Sheet and of the earliest age of the Younger Dryas climate episode in six proxy records, suggesting a causal connection between the YDB impact event and the Younger Dryas. Two statistical tests indicate that both modeled and unmodeled ages in the 30 records are consistent with synchronous deposition of the YDB layer within the limits of dating uncertainty (∼100 y). The widespread distribution of the YDB layer suggests that it may serve as a datum layer. PMID:26216981

  16. Bayesian chronological analyses consistent with synchronous age of 12,835-12,735 Cal B.P. for Younger Dryas boundary on four continents.

    Science.gov (United States)

    Kennett, James P; Kennett, Douglas J; Culleton, Brendan J; Aura Tortosa, J Emili; Bischoff, James L; Bunch, Ted E; Daniel, I Randolph; Erlandson, Jon M; Ferraro, David; Firestone, Richard B; Goodyear, Albert C; Israde-Alcántara, Isabel; Johnson, John R; Jordá Pardo, Jesús F; Kimbel, David R; LeCompte, Malcolm A; Lopinot, Neal H; Mahaney, William C; Moore, Andrew M T; Moore, Christopher R; Ray, Jack H; Stafford, Thomas W; Tankersley, Kenneth Barnett; Wittke, James H; Wolbach, Wendy S; West, Allen

    2015-08-11

    The Younger Dryas impact hypothesis posits that a cosmic impact across much of the Northern Hemisphere deposited the Younger Dryas boundary (YDB) layer, containing peak abundances in a variable assemblage of proxies, including magnetic and glassy impact-related spherules, high-temperature minerals and melt glass, nanodiamonds, carbon spherules, aciniform carbon, platinum, and osmium. Bayesian chronological modeling was applied to 354 dates from 23 stratigraphic sections in 12 countries on four continents to establish a modeled YDB age range for this event of 12,835-12,735 Cal B.P. at 95% probability. This range overlaps that of a peak in extraterrestrial platinum in the Greenland Ice Sheet and of the earliest age of the Younger Dryas climate episode in six proxy records, suggesting a causal connection between the YDB impact event and the Younger Dryas. Two statistical tests indicate that both modeled and unmodeled ages in the 30 records are consistent with synchronous deposition of the YDB layer within the limits of dating uncertainty (∼ 100 y). The widespread distribution of the YDB layer suggests that it may serve as a datum layer.

  17. Quantifying the distribution of nanodiamonds in pre-Younger Dryas to recent age deposits along Bull Creek, Oklahoma Panhandle, USA

    Science.gov (United States)

    Bement, Leland C.; Madden, Andrew S.; Carter, Brian J.; Simms, Alexander R.; Swindle, Andrew L.; Alexander, Hanna M.; Fine, Scott; Benamara, Mourad

    2014-02-01

    High levels of nanodiamonds (nds) have been used to support the transformative hypothesis that an extraterrestrial (ET) event (comet explosion) triggered Younger Dryas changes in temperature, flora and fauna assemblages, and human adaptations [Firestone RB, et al. (2007) Proc Natl Acad Sci USA 104(41):16016-16021]. We evaluate this hypothesis by establishing the distribution of nds within the Bull Creek drainage of the Beaver River basin in the Oklahoma panhandle. The earlier report of an abundance spike of nds in the Bull Creek I Younger Dryas boundary soil is confirmed, although no pure cubic diamonds were identified. The lack of hexagonal nds suggests Bull Creek I is not near any impact site. Potential hexagonal nds at Bull Creek were found to be more consistent with graphene/graphane. An additional nd spike is found in deposits of late Holocene through the modern age, indicating nds are not unique to the Younger Dryas boundary. Nd distributions do not correlate with depositional environment, pedogenesis, climate perturbations, periods of surface stability, or cultural activity.

  18. Quantifying the distribution of nanodiamonds in pre-Younger Dryas to recent age deposits along Bull Creek, Oklahoma panhandle, USA.

    Science.gov (United States)

    Bement, Leland C; Madden, Andrew S; Carter, Brian J; Simms, Alexander R; Swindle, Andrew L; Alexander, Hanna M; Fine, Scott; Benamara, Mourad

    2014-02-04

    High levels of nanodiamonds (nds) have been used to support the transformative hypothesis that an extraterrestrial (ET) event (comet explosion) triggered Younger Dryas changes in temperature, flora and fauna assemblages, and human adaptations [Firestone RB, et al. (2007) Proc Natl Acad Sci USA 104(41):16016-16021]. We evaluate this hypothesis by establishing the distribution of nds within the Bull Creek drainage of the Beaver River basin in the Oklahoma panhandle. The earlier report of an abundance spike of nds in the Bull Creek I Younger Dryas boundary soil is confirmed, although no pure cubic diamonds were identified. The lack of hexagonal nds suggests Bull Creek I is not near any impact site. Potential hexagonal nds at Bull Creek were found to be more consistent with graphene/graphane. An additional nd spike is found in deposits of late Holocene through the modern age, indicating nds are not unique to the Younger Dryas boundary. Nd distributions do not correlate with depositional environment, pedogenesis, climate perturbations, periods of surface stability, or cultural activity.

  19. Multiproxy evidence for terrestrial and aquatic ecosystem responses during the 8.2 ka cold event as recorded at Højby Sø, Denmark

    DEFF Research Database (Denmark)

    Hede, Mikkel Ulfeldt; Rasmussen, Peter; Noe-Nygaard, Nanna

    2010-01-01

    ecosystems to the 8.2 ka cold event. A reduced pollen production by thermophilous deciduous tree taxa in the period c. 8250–8000 cal yr BP reveal that the forest ecosystem was affected by low temperatures during the summer and winter/early-spring seasons. This finding is consistent with the timing of the 8.......2 ka cold event as registered in the Greenland ice cores. At Højby Sø, the climate anomaly appears to have started 200–250 yr earlier than the 8.2 ka cold event as the lake proxy data provide strong evidence for a precipitation-induced distinct increase in catchment soil erosion beginning around 8500...... cal yr BP. Alteration of the terrestrial environment then resulted in a major aquatic ecosystem change with nutrient enrichment of the lake and enhanced productivity, which lasted until c. 7900 cal yr BP. Keywords: 8.2 ka cold event; Lake sediments; Palaeoclimate; Pollen; Macrofossils; Geochemistry...

  20. Snow cover and extreme winter warming events control flower abundance of some, but not all species in high arctic Svalbard

    DEFF Research Database (Denmark)

    Semenchuk, Philipp R.; Elberling, Bo; Cooper, Elisabeth J.

    2013-01-01

    octopetala. However, the affected species were resilient and individuals did not experience any long term effects. In the case of short or cold summers, a subset of species suffered reduced reproductive success, which may affect future plant composition through possible cascading competition effects. Extreme...... winter warming events were shown to expose the canopy to cold winter air. The following summer most of the overwintering flower buds could not produce flowers. Thus reproductive success is reduced if this occurs in subsequent years. We conclude that snow depth influences flower abundance by altering...... events, while Stellaria crassipes responded partly. Snow pack thickness determined whether winter warming events had an effect on flower abundance of some species. Warming events clearly reduced flower abundance in shallow but not in deep snow regimes of Cassiope tetragona, but only marginally for Dryas...

  1. Does Hot Water Freeze Faster Than Cold? Or Why Mpemba's Ice Cream Is a Discrepant Event

    Science.gov (United States)

    Palmer, Bill

    1993-01-01

    A discrepant event is a happening contrary to our current beliefs. Discrepant events are said to be useful in clarifying concepts. This is one of the interesting features of current theories of constructivism. The story of Mpemba's ice cream is quite well known, but it is the educational aspects of the experiment that are of interest in this…

  2. Dynamics of 2013 Sudden Stratospheric Warming event and its impact on cold weather over Eurasia: Role of planetary wave reflection.

    Science.gov (United States)

    Nath, Debashis; Chen, Wen; Zelin, Cai; Pogoreltsev, Alexander Ivanovich; Wei, Ke

    2016-04-07

    In the present study, we investigate the impact of stratospheric planetary wave reflection on tropospheric weather over Central Eurasia during the 2013 Sudden Stratospheric Warming (SSW) event. We analyze EP fluxes and Plumb wave activity fluxes to study the two and three dimensional aspects of wave propagation, respectively. The 2013 SSW event is excited by the combined influence of wavenumber 1 (WN1) and wavenumber 2 (WN2) planetary waves, which makes the event an unusual one and seems to have significant impact on tropospheric weather regime. We observe an extraordinary development of a ridge over the Siberian Tundra and the North Pacific during first development stage (last week of December 2012) and later from the North Atlantic in the second development stage (first week of January 2013), and these waves appear to be responsible for the excitation of the WN2 pattern during the SSW. The wave packets propagated upward and were then reflected back down to central Eurasia due to strong negative wind shear in the upper stratospheric polar jet, caused by the SSW event. Waves that propagated downward led to the formation of a deep trough over Eurasia and brought extreme cold weather over Kazakhstan, the Southern part of Russia and the Northwestern part of China during mid-January 2013.

  3. Measurements and Modeling of Turbulent Fluxes during Persistent Cold Air Pool Events in Salt Lake Valley, Utah

    Science.gov (United States)

    Ivey, C. E.; Sun, X.; Holmes, H.

    2017-12-01

    Land surface processes are important in meteorology and climate research since they control the partitioning of surface energy and water exchange at the earth's surface. The surface layer is coupled to the planetary boundary layer (PBL) by surface fluxes, which serve as sinks or sources of energy, moisture, momentum, and atmospheric pollutants. Quantifying the surface heat and momentum fluxes at the land-atmosphere interface, especially for different surface land cover types, is important because they can further influence the atmospheric dynamics, vertical mixing, and transport processes that impact local, regional, and global climate. A cold air pool (CAP) forms when a topographic depression (i.e., valley) fills with cold air, where the air in the stagnant layer is colder than the air aloft. Insufficient surface heating, which is not able to sufficiently erode the temperature inversion that forms during the nighttime stable boundary layer, can lead to the formation of persistent CAPs during wintertime. These persistent CAPs can last for days, or even weeks, and are associated with increased air pollution concentrations. Thus, realistic simulations of the land-atmosphere exchange are meaningful to achieve improved predictions of the accumulation, transport, and dispersion of air pollution concentrations. The focus of this presentation is on observations and modeling results using turbulence data collected in Salt Lake Valley, Utah during the 2010-2011 wintertime Persistent Cold Air Pool Study (PCAPS). Turbulent fluxes and the surface energy balance over seven land use types are quantified. The urban site has an energy balance ratio (EBR) larger than one (1.276). Negative Bowen ratio (-0.070) is found at the cropland site. In addition to turbulence observations, half-hourly WRF simulated net radiation, latent heat, sensible heat, ground heat fluxes during one persistent CAP event are evaluated using the PCAPS observations. The results show that sensible and latent

  4. The response of southern California ecosystems to Younger Dryas-like rapid climate change: Comparison of glacial terminations 1 and 5.

    Science.gov (United States)

    Heusser, L. E.; Hendy, I. L.

    2015-12-01

    The Younger Dryas is a well-known rapid climatic cooling that interrupted the Marine Isotope Stage (MIS) 1-2 deglacial warming of Termination 1. This cool event has been associated with ice sheet readvance, meridional overturning, circulation changes, and southward movement of the Intertropical Convergence Zone. In Southern California, the Younger Dryas has been associated with cooler SST, low marine productivity, a well-ventilated oxygen minimum zone, and a wetter climate. Similar rapid cooling events have been found at other terminations including Termination 5 at the MIS 11-12 deglaciation (~425 Ka) identified by ice rafting events in the North Atlantic. Here we present new pollen census data from a unique suite of cores taken from the sub-oxic sediments of Santa Barbara Basin (MV0508-15JC, MV0805-20JC, MV0508-33JC, 29JC and 21JC). These short cores, collected on a truncated anticline within SBB, provide the opportunity to examine the response of southern California terrestrial and marine ecosystems to rapid climate change during the MIS 11-12 deglaciation (Termination 5), which is identified by a bioturbated interval within a sequence of laminated sediments. During Termination 1, changes in Southern California precipitation are reflected in pollen- based reconstructions Southern California vegetation. The high precipitation of glacial montane-coniferous assemblages of pine (Pinus) and Juniper (Juniperus/Calocedrus) transitions into interglacial drought, as expresssed by arid oak (Quercus)/chaparral vegetation. The Younger Dryas interrupts the transition as a high-amplitude pulse in pine associated with increased Gramineae (grass). Termination 5 differs, as the high precipitation of glacial montane-coniferous assemblages do not transition into arid oak/chaparral vegetation. However, a Younger Dryas-like rapid climate event was associated with increased pine and grass.

  5. The Younger Dryas phase of Great Salt Lake, Utah, USA

    Science.gov (United States)

    Oviatt, Charles G.; Miller, D.M.; McGeehin, J.P.; Zachary, C.; Mahan, S.

    2005-01-01

    Field investigations at the Public Shooting Grounds (a wildlife-management area on the northeastern shore of Great Salt Lake) and radiocarbon dating show that the Great Salt Lake rose to the Gilbert shoreline sometime between 12.9 and 11.2 cal ka. We interpret a ripple-laminated sand unit exposed at the Public Shooting Grounds, and dated to this time interval, as the nearshore sediments of Great Salt Lake deposited during the formation of the Gilbert shoreline. The ripple-laminated sand is overlain by channel-fill deposits that overlap in age (11.9-11.2 cal ka) with the sand, and by wetland deposits (11.1 to 10.5 cal ka). Consistent accelerator mass spectrometry radiocarbon ages were obtained from samples of plant fragments, including those of emergent aquatic plants, but mollusk shells from spring and marsh deposits yielded anomalously old ages, probably because of a variable radiocarbon reservoir effect. The Bonneville basin was effectively wet during at least part of the Younger Dryas global-cooling interval, however, conflicting results from some Great Basin locations and proxy records indicate that the regional effects of Younger Dryas cooling are still not well understood. ?? 2005 Elsevier B.V. All rights reserved.

  6. Lightning Location System Data from Wind Power Plants Compared to Meteorological Conditions of Warm- and Cold Thunderstorm Events

    DEFF Research Database (Denmark)

    Vogel, Stephan; Lopez, Javier; Garolera, Anna Candela

    2016-01-01

    of topography, height above mean sea level (AMSL), and average ground flash density. For three sites, the most severe lightning events have been identified during the warm and cold months whereas the other two locations exhibit severe lightning detections mainly during the warm months. In this work severity......Five years of Lightning Location System (LLS) data from five different wind turbine sites in Europe are analysed. The sites are located in Croatia, Italy, Spain, France and one offshore wind power plant in the North sea. Each location exhibits individual characteristic properties in terms...... of such an episode can vary from tens of minutes to several hours in the case of new storms being continuously developed in the same area. The distance of the charge separating -10◦ C and the ground is usually larger than 3000 meters. This analyse provides information about the different thunderstorm types which...

  7. Characterization and effects of cold fronts in the Colombian Caribbean Coast and their relationship to extreme wave events

    Science.gov (United States)

    Ortiz-Royero, J. C.; Otero, L. J.; Restrepo, J. C.; Ruiz, J.; Cadena, M.

    2013-07-01

    Extreme ocean waves in the Caribbean Sea are commonly related to the effects of storms and hurricanes during the months of June through November. The collapse of 200 m of the Puerto Colombia pier in March 2009 revealed the effects of meteorological phenomena other than storms and hurricanes that may be influencing the extreme wave regime in the Colombian Caribbean. The marked seasonality of these atmospheric fronts was established by analyzing the meteorological-marine reports of Instituto de Hidrología, Meteorología y Estudios Ambientales of Colombia (IDEAM, based on its initials in Spanish) and Centro de Investigación en Oceanografía y Meteorología of Colombia (CIOH, based on its initials in Spanish). The highest occurrences were observed during the months of January, February, and March, with 6 fronts occurring per year. An annual trend was not observed, although the highest number of fronts occurred in 2010 (20 in total). An annual strong relationship between the maximum average wave values and the cold fronts, in the central zone of the Colombian Caribbean during the first three months of the year was established. In addition, the maximum values of the significant height produced by the passage of cold fronts during the last 16 yr were identified. Although the Colombian Caribbean has been affected by storms and hurricanes in the past, this research allows us to conclude that, there is a strong relationship between cold fronts and the largest waves in the Colombian Caribbean during the last 16 yr, which have caused damage to coastal infrastructure. We verified that the passage of a cold front corresponded to the most significant extreme wave event of the last two decades in the Colombian Caribbean, which caused the structural collapse of the Puerto Colombia pier, located near the city of Barranquilla, between 5 and 10 March 2009. This information is invaluable when evaluating average and extreme wave regimes for the purpose of informing the design of

  8. Environmental response to the cold climate event 8200 years ago as recorded at Hoejby Soe, Denmark

    Energy Technology Data Exchange (ETDEWEB)

    Rasmussen, Peter (Geological Survey of Denmark and Greenland, Copenhagen (Denmark)); Ulfeldt Hede, M.; Noe-Nygaard, N. (Univ. of Copenhagen, Dept. of Geography and Geology, Copenhagen (Denmark)); Clarke, A.L. (APEM Manchester Lab., Stockport (United Kingdom)); Vinebrooke, R.D. (Univ. of Alberta, Dept. of Biological Science - Freshwater Biodiversity Lab., Edmonton (Canada))

    2008-07-15

    The need for accurate predictions of future environmental change under conditions of global warming has led to a great interest in the most pronounced climate change known from the Holocene: an abrupt cooling event around 8200 years before present (present = A.D. 1950), also known as the '8.2 ka cooling event' (ka = kilo-annum = 1000 years). This event has been recorded as a negative delta18OMICRON excursion in the central Greenland ice cores (lasting 160 years with the lowest temperature at 8150) and in a variety of other palaeoclimatic archives including lake sediments, ocean cores, speleothems, tree rings, and glacier oscillations from most of the Northern Hemisphere. In Greenland the maximum cooling was estimated to be 6 +- 2 deg. C while in southern Fennoscandia and the Baltic countries pollenbased quantitative temperature reconstructions indicate a maximum annual mean temperature decrease of around 1.5 deg. C. Today there is a general consensus that the primary cause of the cooling event was the final collapse of the Laurentide ice sheet near Hudson Bay and the associated sudden drainage of the proglacial Lake Agassiz into the North Atlantic Ocean around 8400 B.P. . This freshwater outflow, estimated to amount to c. 164,000 km3 of water, reduced the strength of the North Atlantic thermohaline circulation and thereby the heat transported to the North Atlantic region, resulting in an atmospheric cooling. The climatic consequences of this meltwater flood are assumed to be a good geological analogue for future climate-change scenarios, as a freshening of the North Atlantic is projected by almost all global-warming models and is also currently being registered in the region. In an ongoing project, the influence of the 8.2 ka cooling event on a Danish terrestrial and lake ecosystem is being investigated using a variety of biological and geochemical proxy data from a sediment core extracted from Hojby So, north-west Sjaelland. Here we present data on

  9. Hunted gazelles evidence cooling, but not drying, during the Younger Dryas in the southern Levant

    Science.gov (United States)

    Hartman, Gideon; Bar-Yosef, Ofer; Brittingham, Alex; Grosman, Leore; Munro, Natalie D.

    2016-04-01

    The climatic downturn known globally as the Younger Dryas (YD; ∼12,900-11,500 BP) has frequently been cited as a prime mover of agricultural origins and has thus inspired enthusiastic debate over its local impact. This study presents seasonal climatic data from the southern Levant obtained from the sequential sampling of gazelle tooth carbonates from the Early and Late Natufian archaeological sites of Hayonim and Hilazon Tachtit Caves (western Galilee, Israel). Our results challenge the entrenched model that assumes that warm temperatures and high precipitation are synonymous with climatic amelioration and cold and wet conditions are combined in climatic downturns. Enamel carbon isotope values from teeth of human-hunted gazelle dating before and during the YD provide a proxy measure for water availability during plant growth. They reveal that although the YD was cooler, it was not drier than the preceding Bølling-Allerød. In addition, the magnitude of the seasonal curve constructed from oxygen isotopes is significantly dampened during the YD, indicating that cooling was most pronounced in the growing season. Cool temperatures likely affected the productivity of staple wild cereal resources. We hypothesize that human groups responded by shifting settlement strategies-increasing population mobility and perhaps moving to the warmer Jordan Valley where wild cereals were more productive and stable.

  10. Coupled prediction of flood response and debris flow initiation during warm and cold season events in the Southern Appalachians, USA

    Science.gov (United States)

    Tao, J.; Barros, A. P.

    2013-07-01

    Debris flows associated with rainstorms are a frequent and devastating hazard in the Southern Appalachians in the United States. Whereas warm season events are clearly associated with heavy rainfall intensity, the same cannot be said for the cold season events. Instead, there is a relationship between large (cumulative) rainfall events independently of season, and thus hydrometeorological regime, and debris flows. This suggests that the dynamics of subsurface hydrologic processes play an important role as a trigger mechanism, specifically through soil moisture redistribution by interflow. The first objective of this study is to investigate this hypothesis. The second objective is to assess the physical basis for a regional coupled flood prediction and debris flow warning system. For this purpose, uncalibrated model simulations of well-documented debris flows in headwater catchments of the Southern Appalachians using a 3-D surface-groundwater hydrologic model coupled with slope stability models are examined in detail. Specifically, we focus on two vulnerable headwater catchments that experience frequent debris flows, the Big Creek and the Jonathan Creek in the Upper Pigeon River Basin, North Carolina, and three distinct weather systems: an extremely heavy summertime convective storm in 2011; a persistent winter storm lasting several days; and a severe winter storm in 2009. These events were selected due to the optimal availability of rainfall observations, availability of detailed field surveys of the landslides shortly after they occurred, which can be used to evaluate model predictions, and because they are representative of events that cause major economic losses in the region. The model results substantiate that interflow is a useful prognostic of conditions necessary for the initiation of slope instability, and should therefore be considered explicitly in landslide hazard assessments. Moreover, the relationships between slope stability and interflow are

  11. Orbital forcing of the late Pleistocene boreal summer monsoon: Links to North Atlantic cold events and El Nino; Southern Oscillation. Geologica Ultraiectina (313)

    NARCIS (Netherlands)

    Ziegler, M.

    2009-01-01

    This thesis revolves about the timing of precession-related variations in the boreal summer monsoon and the impact of North Atlantic cold events and the El Nino Southern Oscillation on this timing. Transient climate modelling experiments indicate that the intensity of the Northern Hemisphere summer

  12. Atmospheric 14C variations derived from tree rings during the early Younger Dryas

    Science.gov (United States)

    Hua, Quan; Barbetti, Mike; Fink, David; Kaiser, Klaus Felix; Friedrich, Michael; Kromer, Bernd; Levchenko, Vladimir A.; Zoppi, Ugo; Smith, Andrew M.; Bertuch, Fiona

    2009-12-01

    Atmospheric radiocarbon variations over the Younger Dryas interval, from ˜13,000 to 11,600 cal yr BP, are of immense scientific interest because they reveal crucial information about the linkages between climate, ocean circulation and the carbon cycle. However, no direct and reliable atmospheric 14C records based on tree rings for the entire Younger Dryas have been available. In this paper, we present (1) high-precision 14C measurements on the extension of absolute tree-ring chronology from 12,400 to 12,560 cal yr BP and (2) high-precision, high-resolution atmospheric 14C record derived from a 617-yr-long tree-ring chronology of Huon pine from Tasmania, Australia, spanning the early Younger Dryas. The new tree-ring 14C records bridge the current gap in European tree-ring radiocarbon chronologies during the early Younger Dryas, linking the floating Lateglacial Pine record to the absolute tree-ring timescale. A continuous and reliable atmospheric 14C record for the past 14,000 cal yr BP including the Younger Dryas is now available. The new records indicate that the abrupt rise in atmospheric Δ 14C associated with the Younger Dryas onset occurs at ˜12,760 cal yr BP, ˜240 yrs later than that recorded in Cariaco varves, with a smaller magnitude of ˜40‰ followed by several centennial Δ 14C variations of 20-25‰. Comparing the tree-ring Δ 14C to marine-derived Δ 14C and modelled Δ 14C based on ice-core 10Be fluxes, we conclude that changes in ocean circulation were mainly responsible for the Younger Dryas onset, while a combination of changes in ocean circulation and 14C production rate were responsible for atmospheric Δ 14C variations for the remainder of the Younger Dryas.

  13. Spatial variability and trends in Younger Dryas equilibrium line altitudes across the European Alps using a hypsometrically based ELA model: results and implications

    Science.gov (United States)

    Keeler, D. G.; Rupper, S.; Schaefer, J. M.; Finkel, R. C.; Maurer, J. M.

    2016-12-01

    Alpine glaciers constitute an important component of terrestrial paleoclimate records due to, among other characteristics, their high sensitivity to climate change, near global extent, and their integration of myriad climate variables into a single, easily detected signal. Because the glacier equilibrium line altitude (ELA) provides a more explicit representation of climate than many other glacier properties, ELA methods allow for more direct comparisons of multiple glaciers within or between regions. Such comparisons allow for more complete investigations of the ultimate causes of mountain glaciation during specific events. Many studies however tend to focus on a limited number of sites, and employ a large variety of different techniques for ELA reconstruction between studies, making wider climate implications more tenuous. Methods of ELA reconstruction that can be rapidly and consistently applied to an arbitrary number of paleo-glaciers would provide a more accurate portrayal of the changes in climate across a given region. Here we present ELA reconstructions from Egesen Stadial moraines across the European Alps using an ELA model accounting for differences in glacier width, glacier shape, bed topography, ice thickness, and glacier length, including several glaciers constrained to the Younger Dryas using surface exposure dating techniques. We compare reconstructed Younger Dryas ELA values to modern ELA values using the same model, or using end of summer snowline estimates where no glacier is currently present. We further provide uncertainty estimates on the ΔELA using bootstrapped Monte Carlo simulations for the various input parameters. Preliminary results compare favorably to previous glacier studies of the European Younger Dryas, but provide greater context from many glaciers across the region as a whole. Such results allow for a more thorough investigation of the spatial variability and trends in climate during the Younger Dryas across the European Alps, and

  14. REVISITING THE MICROLENSING EVENT OGLE 2012-BLG-0026: A SOLAR MASS STAR WITH TWO COLD GIANT PLANETS

    International Nuclear Information System (INIS)

    Beaulieu, J.-P.; Batista, V.; Marquette, J.-B.

    2016-01-01

    Two cold gas giant planets orbiting a G-type main-sequence star in the galactic disk were previously discovered in the high-magnification microlensing event OGLE-2012-BLG-0026. Here, we present revised host star flux measurements and a refined model for the two-planet system using additional light curve data. We performed high angular resolution adaptive optics imaging with the Keck and Subaru telescopes at two epochs while the source star was still amplified. We detected the lens flux, H = 16.39 ± 0.08. The lens, a disk star, is brighter than predicted from the modeling in the original study. We revisited the light curve modeling using additional photometric data from the B and C telescope in New Zealand and CTIO 1.3 m H -band light curve. We then include the Keck and Subaru adaptive optic observation constraints. The system is composed of a ∼4–9 Gyr lens star of M lens = 1.06 ± 0.05 M ⊙ at a distance of D lens = 4.0 ± 0.3 kpc, orbited by two giant planets of 0.145 ± 0.008 M Jup and 0.86 ± 0.06 M Jup , with projected separations of 4.0 ± 0.5 au and 4.8 ± 0.7 au, respectively. Because the lens is brighter than the source star by 16 ± 8% in H, with no other blend within one arcsec, it will be possible to estimate its metallicity using subsequent IR spectroscopy with 8–10 m class telescopes. By adding a constraint on the metallicity it will be possible to refine the age of the system.

  15. Revisiting the Microlensing Event OGLE 2012-BLG-0026: A Solar Mass Star with Two Cold Giant Planets

    Science.gov (United States)

    Beaulieu, J.-P.; Bennett, D. P.; Batista, V.; Fukui, A.; Marquette, J.-B.; Brillant, S.; Cole, A. A.; Rogers, L. A.; Sumi, T.; Abe, F.

    2016-01-01

    Two cold gas giant planets orbiting a G-type main-sequence star in the galactic disk were previously discovered in the high-magnification microlensing event OGLE-2012-BLG-0026. Here, we present revised host star flux measurements and a refined model for the two-planet system using additional light curve data. We performed high angular resolution adaptive optics imaging with the Keck and Subaru telescopes at two epochs while the source star was still amplified. We detected the lens flux, H = 16.39 +/- 0.08. The lens, a disk star, is brighter than predicted from the modeling in the original study. We revisited the light curve modeling using additional photometric data from the B and C telescope in New Zealand and CTIO 1.3 m H-band light curve. We then include the Keck and Subaru adaptive optic observation constraints. The system is composed of an approximately 4-9 Gyr lens star of M(sub lens) = 1.06 +/- 0.05 solar mass at a distance of D(sub lens) = 4.0 +/- 0.3 kpc, orbited by two giant planets of 0.145 +/- 0.008 M(sub Jup) and 0.86 +/- 0.06 M(sub Jup), with projected separations of 4.0 +/- 0.5 au and 4.8 +/- 0.7 au, respectively. Because the lens is brighter than the source star by 16 +/- 8% in H, with no other blend within one arcsec, it will be possible to estimate its metallicity using subsequent IR spectroscopy with 8-10 m class telescopes. By adding a constraint on the metallicity it will be possible to refine the age of the system.

  16. Cold-climate slope deposits and landscape modifications of the Mid-Atlantic Coastal Plain, Eastern USA

    Science.gov (United States)

    Newell, Wayne L.; Dejong, B.D.

    2011-01-01

    The effects of Pleistocene cold-climate geomorphology are distributed across the weathered and eroded Mid-Atlantic Coastal Plain uplands from the Wisconsinan terminal moraine south to Tidewater Virginia. Cold-climate deposits and landscape modifications are superimposed on antecedent landscapes of old, weathered Neogene upland gravels and Pleistocene marine terraces that had been built during warm periods and sea-level highstands. In New Jersey, sequences of surficial deposits define a long history of repeating climate change events. To the south across the Delmarva Peninsula and southern Maryland, most antecedent topography has been obscured by Late Pleistocene surficial deposits. These are spatially variable and are collectively described as a cold-climate alloformation. The cold-climate alloformation includes time-transgressive details of climate deterioration from at least marine isotope stage (MIS) 4 through the end of MIS 2. Some deposits and landforms within the alloformation may be as young as the Younger Dryas. Southwards along the trend of the Potomac River, these deposits and their climatic affinities become diffused. In Virginia, a continuum of erosion and surficial deposits appears to be the product of ‘normal’ temperate, climate-forced processes. The cold-climate alloformation and more temperate deposits in Virginia are being partly covered by Holocene alluvium and bay mud.

  17. Nanodiamonds and wildfire evidence in the Usselo horizon postdate the Allerod-Younger Dryas boundary.

    Science.gov (United States)

    van Hoesel, Annelies; Hoek, Wim Z; Braadbaart, Freek; van der Plicht, Johannes; Pennock, Gillian M; Drury, Martyn R

    2012-05-15

    The controversial Younger Dryas impact hypothesis suggests that at the onset of the Younger Dryas an extraterrestrial impact over North America caused a global catastrophe. The main evidence for this impact--after the other markers proved to be neither reproducible nor consistent with an impact--is the alleged occurrence of several nanodiamond polymorphs, including the proposed presence of lonsdaleite, a shock polymorph of diamond. We examined the Usselo soil horizon at Geldrop-Aalsterhut (The Netherlands), which formed during the Allerød/Early Younger Dryas and would have captured such impact material. Our accelerator mass spectrometry radiocarbon dates of 14 individual charcoal particles are internally consistent and show that wildfires occurred well after the proposed impact. In addition we present evidence for the occurrence of cubic diamond in glass-like carbon. No lonsdaleite was found. The relation of the cubic nanodiamonds to glass-like carbon, which is produced during wildfires, suggests that these nanodiamonds might have formed after, rather than at the onset of, the Younger Dryas. Our analysis thus provides no support for the Younger Dryas impact hypothesis.

  18. Variations in fluid chemistry and membrane phospholipid fatty acid composition of the bacterial community in a cold storage groundwater system during clogging events

    International Nuclear Information System (INIS)

    Vetter, Alexandra; Mangelsdorf, Kai; Wolfgramm, Markus; Rauppach, Kerstin; Schettler, Georg; Vieth-Hillebrand, Andrea

    2012-01-01

    In order to monitor the operating mode of the cold storage of the German Parliament (North German Basin) the fluid chemistry and the phospholipid fatty acid (PLFA) composition of the indigenous microbial community have been monitored from August 2006 to August 2009. During this time two periods of reduced injection (clogging events) characterized by Fe precipitates and microbial biofilms in filters occurred in the injection wells impairing the operating state of the investigated cold storage. The fluid monitoring revealed the presence of sufficient amounts of potential C and energy sources (e.g. DOC and SO 4 2- ) in the process water to sustain microbial life in the cold storage. In times of reduced injection the PLFA inventory of the microbial community differs significantly from times of normal operating phases indicating compositional changes in the indigenous microbial ecosystem. The most affected fatty acids (FAs) are 16:1ω7c (increase), 16:1ω7t (decrease) and 18:1ω7c (increase), interpreted to originate mainly from Fe and S oxidizers, as well as branched FA with 15, 16 and 17 C atoms (decrease) most likely representing sulfate-reducing bacteria (SRB). Based on this variability, PLFA ratios have been created to reflect the increasing dominance of biofilm forming S and Fe oxidizers during the disturbance periods. These ratios are potential diagnostic tools to assess the microbiological contribution to the clogging events and to find appropriate counteractive measures (e.g. mechanical cleaning vs disinfection). The correlation between changes in the PLFA composition and the operational state suggests that microbially mediated processes play a significant role in the observed clogging events in the investigated cold storage.

  19. Nanodiamonds and wildfire evidence in the Usselo horizon postdate the Allerød-Younger Dryas boundary

    NARCIS (Netherlands)

    Hoesel, A. van; Hoek, W.Z.; Braadbaart, F.; Plicht, J. van der; Pennock, G.M.; Drury, M.R.

    2012-01-01

    The controversial Younger Dryas impact hypothesis suggests that at the onset of the Younger Dryas an extraterrestrial impact over North America caused a global catastrophe. The main evidence for this impact—after the other markers proved to be neither reproducible nor consistent with an impact—is

  20. Nanodiamonds and wildfire evidence in the Usselo horizon postdate the Allerød-Younger Dryas boundary

    NARCIS (Netherlands)

    Van Hoesel, Annelies; Hoek, Wim Z.; Braadbaart, Freek; Van Der Plicht, Johannes; Pennock, Gillian M.; Drury, Martyn R.

    2012-01-01

    The controversial Younger Dryas impact hypothesis suggests that at the onset of the Younger Dryas an extraterrestrial impact over North America caused a global catastrophe. The main evidence for this impact - after the other markers proved to be neither reproducible nor consistent with an impact -

  1. Proliferation and demise of deep-sea corals in the Mediterranean during the Younger Dryas

    International Nuclear Information System (INIS)

    McCulloch, Malcolm; Taviani, Marco; Lopez Correa, Matthias; Remia, Alessandro; Montagna, Paolo; Mortimer, Graham

    2010-01-01

    Uranium-series and radiocarbon ages are reported for deep-sea corals Madrepora oculata, Desmophyllum dianthus, Lophelia pertusa and Caryophyllia smithii from the Mediterranean Sea. U-series dating indicates that deep-sea corals have persisted in the Mediterranean for over 480, 000 years, especially during cool inter-stadial periods. The most prolific period of growth however appears to have occurred within the Younger Dryas (YD) period from 12, 900 to 11, 700 years BP followed by a short (∼ 330 years) phase of post-YD coral growth from 11, 230 to 10, 900 years BP. This indicates that deep-sea corals were prolific in the Mediterranean not only during the return to the more glacial-like conditions of the YD, but also following the rapid deglaciation and transition to warmer conditions that followed the end of the YD. Surprisingly, there is a paucity Last Glacial Maximum (LGM) coral ages, implying they were largely absent during this period when cold-water conditions were more prevalent. Radiocarbon ages show that the intermediate depth waters of the Mediterranean generally had Δ 14 C compositions similar to surface waters, indicating that these waters were extremely well ventilated. The only exception is a narrow period in the YD (12, 500 ± 100 years BP) when several samples of Lophelia pertusa from the Ionian Sea had Δ 14 C values falling significantly below the marine curve. Using a refined approach, isolation ages (T isol ) of 300 years to 500 years are estimated for these intermediate (800-1000 m) depth waters relative to surface marine waters, indicating a reduction or absence of deep-water formation in the Ionian and adjacent Adriatic Seas during the YD. Contrary to previous findings, we find no evidence for widespread intrusion of low Δ 14 C Atlantic waters into the Mediterranean. Prolific growth of deep-sea corals in the Mediterranean ended abruptly at ∼ 10, 900 years BP, with many of the coral-bearing mounds on the continental slopes being draped in

  2. Proliferation and demise of deep-sea corals in the Mediterranean during the Younger Dryas

    Energy Technology Data Exchange (ETDEWEB)

    McCulloch, Malcolm [ARC Centre of Excellence for Coral Reef Studies, School of Earth and Environment, The University of Western Australian, Crawley, 6009, Western Australia (Australia); Research School of Earth Sciences, Australian National University, Canberra, 0200 (Australia); Taviani, Marco; Lopez Correa, Matthias; Remia, Alessandro [ISMAR-CNR, via Gobetti 101, I-40129 Bologna (Italy); Montagna, Paolo [LSCE, Av. de la Terrasse, 91198 Gif-sur-Yvette, France, ISMAR-CNR, via Gobetti 101, I-40129 Bologna (Italy); Mortimer, Graham [Research School of Earth Sciences, Australian National University, Canberra, 0200 (Australia)

    2010-07-01

    Uranium-series and radiocarbon ages are reported for deep-sea corals Madrepora oculata, Desmophyllum dianthus, Lophelia pertusa and Caryophyllia smithii from the Mediterranean Sea. U-series dating indicates that deep-sea corals have persisted in the Mediterranean for over 480, 000 years, especially during cool inter-stadial periods. The most prolific period of growth however appears to have occurred within the Younger Dryas (YD) period from 12, 900 to 11, 700 years BP followed by a short ({approx} 330 years) phase of post-YD coral growth from 11, 230 to 10, 900 years BP. This indicates that deep-sea corals were prolific in the Mediterranean not only during the return to the more glacial-like conditions of the YD, but also following the rapid deglaciation and transition to warmer conditions that followed the end of the YD. Surprisingly, there is a paucity Last Glacial Maximum (LGM) coral ages, implying they were largely absent during this period when cold-water conditions were more prevalent. Radiocarbon ages show that the intermediate depth waters of the Mediterranean generally had {Delta}{sup 14}C compositions similar to surface waters, indicating that these waters were extremely well ventilated. The only exception is a narrow period in the YD (12, 500 {+-} 100 years BP) when several samples of Lophelia pertusa from the Ionian Sea had {Delta}{sup 14}C values falling significantly below the marine curve. Using a refined approach, isolation ages (T{sub isol}) of 300 years to 500 years are estimated for these intermediate (800-1000 m) depth waters relative to surface marine waters, indicating a reduction or absence of deep-water formation in the Ionian and adjacent Adriatic Seas during the YD. Contrary to previous findings, we find no evidence for widespread intrusion of low {Delta}{sup 14}C Atlantic waters into the Mediterranean. Prolific growth of deep-sea corals in the Mediterranean ended abruptly at {approx} 10, 900 years BP, with many of the coral-bearing mounds

  3. Human Population Decline in North America during the Younger Dryas

    Science.gov (United States)

    Anderson, D. G.; Goodyear, A. C.; Stafford, T. W., Jr.; Kennett, J.; West, A.

    2009-12-01

    There is ongoing debate about a possible human population decline or contraction at the onset of the Younger Dryas (YD) at 12.9 ka. We used two methods to test whether the YD affected human population levels: (1) frequency analyses of Paleoindian projectile points, and (2) summed probability analyses of radiocarbon (14C) dates. The results suggest that a significant decline or reorganization of human populations occurred at 12.9 ka, continued through the initial centuries of the YD chronozone, then rebounded by the end of the YD. FREQUENCY ANALYSES: This method employed projectile point data from the Paleoindian Database of the Americas (PIDBA, http://pidba.utk.edu). We tallied diagnostic projectile points and obtained larger totals for Clovis points than for immediately post-Clovis points, which share an instrument-assisted fluting technique, typically using pressure or indirect percussion. Gainey, Vail, Debert, Redstone, and Cumberland point-styles utilized this method and are comparable to the Folsom style. For the SE U.S., the ratio of Clovis points (n=1993) to post-Clovis points (n=947) reveals a point decline of 52%. For the Great Plains, a comparison of Clovis and fluted points (n=4020) to Folsom points (n=2527) shows a point decline of 37%, which may translate into a population contraction of similar magnitude. In addition, eight major Clovis lithic quarry sites in the SE U.S. exhibit little to no evidence for immediate post-Clovis occupations, implying a major population decline. SUMMED PROBABILITIES: This method involved calibrating relevant 14C dates and combining the probabilities, after which major peaks and troughs in the trends are assumed to reflect changes in human demographics. Using 14C dates from Buchanan et al. (2008), we analyzed multiple regions, including the Southeast and Great Plains. Contrary to Buchanan et al., we found an abrupt, statistically significant decline at 12.9 ka, followed 200 to 900 years later by a rebound in the number of

  4. Hydrological and vegetational response to the Younger Dryas climatic oscillations: a high resolution case study from Quoyloo Meadow, Orkney, Scotland

    Science.gov (United States)

    Maas, David; Abrook, Ashley; Timms, Rhys; Matthews, Ian; Palmer, Adrian; Milner, Alice; Candy, Ian; Sachse, Dirk

    2016-04-01

    The Younger Dryas (Loch Lomond) Stadial is a well defined period of cold climate that in North West Europe punctuated the climatic amelioration during the Last Glacial - Interglacial Transition (LGIT ca. 16-8 ka). A palaeolake record from Quoyloo Meadow, Orkney Islands (N59.067, E-3.309) has been analysed for pollen and stable isotopes on biomarker lipids. n-Alkanes from terrestrial and aquatic sources are present throughout the core. The average chain length (ACL) is relatively low during the interstadial (~28.0) and shows a distinct increase during the Younger Dryas (to 29.0 +), attributed to an increase in grasses and drought resistant shrubs (e.g. Artemisia, Castañeda et al., 2009, Bunting, 1994). At the beginning of the Holocene, the ACL rapidly drops to 28.3 and from thereon gently increases again to ~29.0. There is a continued odd-over-even n-alkane predominance, although even n-alkanes are present in greater quantities in the interstadial, indicating an increasing terrestrial contribution in the Holocene. Ongoing deuterium isotope measurements of the n-alkanes will give independent evidence for palaeohydrological changes and can be compared to the other proxy evidence within the same core. Using a combination of nC29 and nC23 (terrestrial and aquatic end-members, respectively), a change in relative humidity (rH) can be qualified. This is based on the idea that terrestrial vegetation is affected by evapotranspiration processes, whereas aquatic vegetation is not (Rach et al., 2014). This data is supported by a high resolution palynological study; the contiguously sampled record demonstrates ecosystem/environmental responses to millennial-scale climatic change and allows for the possible detection of vegetation shifts at the sub-millennial scale. Vegetation aside, the pollen data can further aid in the interpretation of the recorded n-alkanes and isotopic analyses. This data is placed within a chronological framework derived from a high resolution crypto- and

  5. Glacial cold-water coral growth in the Gulf of Cádiz: Implications of increased palaeo-productivity

    Science.gov (United States)

    Wienberg, Claudia; Frank, Norbert; Mertens, Kenneth N.; Stuut, Jan-Berend; Marchant, Margarita; Fietzke, Jan; Mienis, Furu; Hebbeln, Dierk

    2010-10-01

    A set of 40 Uranium-series datings obtained on the reef-forming scleractinian cold-water corals Lophelia pertusa and Madrepora oculata revealed that during the past 400 kyr their occurrence in the Gulf of Cádiz (GoC) was almost exclusively restricted to glacial periods. This result strengthens the outcomes of former studies that coral growth in the temperate NE Atlantic encompassing the French, Iberian and Moroccan margins dominated during glacial periods, whereas in the higher latitudes (Irish and Norwegian margins) extended coral growth prevailed during interglacial periods. Thus it appears that the biogeographical limits for sustained cold-water coral growth along the NE Atlantic margin are strongly related to climate change. By focussing on the last glacial-interglacial cycle, this study shows that palaeo-productivity was increased during the last glacial. This was likely driven by the fertilisation effect of an increased input of aeolian dust and locally intensified upwelling. After the Younger Dryas cold event, the input of aeolian dust and productivity significantly decreased concurrent with an increase in water temperatures in the GoC. This primarily resulted in reduced food availability and caused a widespread demise of the formerly thriving coral ecosystems. Moreover, these climate induced changes most likely caused a latitudinal shift of areas with optimum coral growth conditions towards the northern NE Atlantic where more suitable environmental conditions established with the onset of the Holocene.

  6. Cold Stress

    Science.gov (United States)

    ... Publications and Products Programs Contact NIOSH NIOSH COLD STRESS Recommend on Facebook Tweet Share Compartir Workers who ... cold environments may be at risk of cold stress. Extreme cold weather is a dangerous situation that ...

  7. Enhanced aridity and atmospheric high-pressure stability over the western Mediterranean during the North Atlantic cold events of the past 50 k.y.

    Science.gov (United States)

    Combourieu Nebout, N.; Turon, J. L.; Zahn, R.; Capotondi, L.; Londeix, L.; Pahnke, K.

    2002-10-01

    Multiproxy paleoenvironmental records (pollen and planktonic isotope) from Ocean Drilling Program Site 976 (Alboran Sea) document rapid ocean and climate variations during the last glacial that follow the Dansgaard-Oeschger climate oscillations seen in the Greenland ice core records, thus suggesting a close link of the Mediterranean climate swings with North Atlantic climates. Continental conditions rapidly oscillated through cold-arid and warm-wet conditions in the course of stadial-interstadial climate jumps. At the time of Heinrich events, i.e., maximum meltwater flux to the North Atlantic, western Mediterranean marine microflora and microfauna show rapid cooling correlated with increasing continental dryness. Enhanced aridity conceivably points to prolonged wintertime stability of atmospheric high-pressure systems over the southwestern Mediterranean in conjunction with cooling of the North Atlantic.

  8. Lateglacial landscape and vegetation change and the younger dryas climatic oscillation in New Zealand

    Science.gov (United States)

    McGlone, M. S.

    Lateglacial sequences in New Zealand show progressive afforestation and landscape stabilization reflecting a warming climate. Between 14,500 BP and 11,500 BP, afforestation and landscape stability was achieved throughout most of the North Island and the northwest sector of the South Island. In the South Island, scrub and tree ferns were replacing previous grasslands in the east by 11,000 BP, and broadleaved forest was spreading in the west. No significant reversals of these trends occurred and afforestation was complete by 9500 BP. Glaciers of the high central part of the Southern Alps made a series of advances between 14,000 and 9000 BP Most of these advances are poorly dated but two moraines are of Younger Dryas age. Glacial advances in the face of the general Lateglacial warming trend may have been driven by stronger westerly winds increasing snowfall on high altitude névés, and by reduced ablation as a consequence of moist, cloudy, low insolation summers. The cause of the northern hemisphere Younger Dryas cooling is still uncertain, and expected Southern Hemisphere responses may differ according to the mechanism proposed for the cooling. Poor chronological resolution and apparent conflict between the various types of evidence for climatic change make detection of an unambiguous Younger Dryas in New Zealand problematical.

  9. Events

    Directory of Open Access Journals (Sweden)

    Igor V. Karyakin

    2016-02-01

    Full Text Available The 9th ARRCN Symposium 2015 was held during 21st–25th October 2015 at the Novotel Hotel, Chumphon, Thailand, one of the most favored travel destinations in Asia. The 10th ARRCN Symposium 2017 will be held during October 2017 in the Davao, Philippines. International Symposium on the Montagu's Harrier (Circus pygargus «The Montagu's Harrier in Europe. Status. Threats. Protection», organized by the environmental organization «Landesbund für Vogelschutz in Bayern e.V.» (LBV was held on November 20-22, 2015 in Germany. The location of this event was the city of Wurzburg in Bavaria.

  10. Coupled prediction of flood response and debris flow initiation during warm- and cold-season events in the Southern Appalachians, USA

    Science.gov (United States)

    Tao, J.; Barros, A. P.

    2014-01-01

    Debris flows associated with rainstorms are a frequent and devastating hazard in the Southern Appalachians in the United States. Whereas warm-season events are clearly associated with heavy rainfall intensity, the same cannot be said for the cold-season events. Instead, there is a relationship between large (cumulative) rainfall events independently of season, and thus hydrometeorological regime, and debris flows. This suggests that the dynamics of subsurface hydrologic processes play an important role as a trigger mechanism, specifically through soil moisture redistribution by interflow. We further hypothesize that the transient mass fluxes associated with the temporal-spatial dynamics of interflow govern the timing of shallow landslide initiation, and subsequent debris flow mobilization. The first objective of this study is to investigate this relationship. The second objective is to assess the physical basis for a regional coupled flood prediction and debris flow warning system. For this purpose, uncalibrated model simulations of well-documented debris flows in headwater catchments of the Southern Appalachians using a 3-D surface-groundwater hydrologic model coupled with slope stability models are examined in detail. Specifically, we focus on two vulnerable headwater catchments that experience frequent debris flows, the Big Creek and the Jonathan Creek in the Upper Pigeon River Basin, North Carolina, and three distinct weather systems: an extremely heavy summertime convective storm in 2011; a persistent winter storm lasting several days; and a severe winter storm in 2009. These events were selected due to the optimal availability of rainfall observations; availability of detailed field surveys of the landslides shortly after they occurred, which can be used to evaluate model predictions; and because they are representative of events that cause major economic losses in the region. The model results substantiate that interflow is a useful prognostic of conditions

  11. Evidences of melting of terrestrial sediments and paleoenvironment changes during the Younger Dryas in tectonic lacustrine basins of Transmexican Volcanic Belt, Mexico.

    Science.gov (United States)

    Israde-Alcantara, I.

    2017-12-01

    It is well known in the sedimentary record of several parts of the world that during the Younger Dryas interval (YD) ocurred an abrupt environmental change between 12,900 and 11,700 cal yr BP (10,900 to 10,000 14C BP). In the lacustrine basins this changes are often preserved and in some Mexican lakes this is a distinctive stratigraphic marker for the YD. We analized the proxies of this event in cores of two lakes (Chapala, Cuitzeo) and three trenches of ex-lakes (Acambay,Texcoco and El Cedral). Deposits consist of fine detrital material with often Pleistocene fossil vertebrate assemblages. At the Chapala, Cuitzeo, Acambay, and Tocuila lacustrine environments are found in association with a distinctive dark organic layer showing sharp changes in the diatom, pollen, mineralogical and geochemical record. Includes also microscopic magnetic, Fe-rich spherules, silica melted droplets with aerodynamic shapes (tektites), followed by large amounts of charcoal, and sometimes nanodiamonds (Cuitzeo), that were deposited at the onset of the YD or in the limit Pleistocene-Holocene. These unusual materials are buried more than 2.50 meters and were not observed above or below the Younger Dryas sediments at these sites. The geochemistry of the microspherules indicates that they are not volcanic, anthropogenic or authigenic origin. A very distinctive feature is the shape of the spherules, ovoid, polygonal, filigreed or dendritic indicating melting and quenching infering that are product of an impact event. Their morphologies includes hollow shells caused by de-gassing of elements at very high temperatures causing a flattened side with a "skirt" structure by a high-velocity collision.Our results are consistent with the Firestone hypothesis.

  12. Nanodiamonds and wildfire evidence in the Usselo horizon postdate the Allerød-Younger Dryas boundary

    Science.gov (United States)

    van Hoesel, Annelies; Hoek, Wim Z.; Braadbaart, Freek; van der Plicht, Johannes; Pennock, Gillian M.; Drury, Martyn R.

    2012-01-01

    The controversial Younger Dryas impact hypothesis suggests that at the onset of the Younger Dryas an extraterrestrial impact over North America caused a global catastrophe. The main evidence for this impact—after the other markers proved to be neither reproducible nor consistent with an impact—is the alleged occurrence of several nanodiamond polymorphs, including the proposed presence of lonsdaleite, a shock polymorph of diamond. We examined the Usselo soil horizon at Geldrop-Aalsterhut (The Netherlands), which formed during the Allerød/Early Younger Dryas and would have captured such impact material. Our accelerator mass spectrometry radiocarbon dates of 14 individual charcoal particles are internally consistent and show that wildfires occurred well after the proposed impact. In addition we present evidence for the occurrence of cubic diamond in glass-like carbon. No lonsdaleite was found. The relation of the cubic nanodiamonds to glass-like carbon, which is produced during wildfires, suggests that these nanodiamonds might have formed after, rather than at the onset of, the Younger Dryas. Our analysis thus provides no support for the Younger Dryas impact hypothesis. PMID:22547791

  13. Problems with the Younger Dryas Boundary (YDB) Impact Hypothesis

    Science.gov (United States)

    Boslough, M.

    2009-12-01

    One breakthrough of 20th-century Earth science was the recognition of impacts as an important geologic process. The most obvious result is a crater. There are more than 170 confirmed terrestrial impact structures with a non-uniform spatial distribution suggesting more to be found. Many have been erased by tectonics and erosion. Deep water impacts do not form craters, and craters in ice sheets disappear when the ice melts. There is growing speculation that such hidden impacts have caused frequent major environmental events of the Holocene, but this is inconsistent with the astronomically-constrained population of Earth-crossing asteroids. Impacts can have consequences much more significant than excavation of a crater. The K/T boundary mass extinction is attributed to the environmental effects of a major impact, and some researchers argue that other extinctions, abrupt climate changes, and even civilization collapses have resulted from impacts. Nuclear winter models suggest that 2-km diameter asteroids exceed a "global catastrophe threshold" by injecting sufficient dust into the stratosphere to cause short-term climate changes, but would not necessarily collapse most natural ecosystems or cause mass extinctions. Globally-catastrophic impacts recur on timescales of about one million years. The 1994 collision of Comet Shoemaker-Levy 9 with Jupiter led us recognize the significance of terrestrial airbursts caused by objects exploding violently in Earth’s atmosphere. We have invoked airbursts to explain rare forms of non-volcanic glasses and melts by using high-resolution computational models to improve our understanding of atmospheric explosions, and have suggested that multiple airbursts from fragmented impactors could be responsible for regional effects. Our models have been cited in support of the widely-publicized YDB impact hypothesis. Proponents claim that a broken comet exploded over North America, with some fragments cratering the Laurentide Ice Sheet. They

  14. Evidence for an extraterrestrial impact 12,900 years ago that contributed to megafaunal extinctions and the Younger Dryas cooling

    International Nuclear Information System (INIS)

    Firestone, R.B.; West, A.; Kennett, J.P.; Becker, L.; Bunch, T.E.; Revay, Z.S.; Schultz, P.H.; Belgya, T.; Kennett, D.J.; Erlandson, J.M.; Dickenson, O.J.; Goodyear, A.C.; Harris, R.S.; Howard, G.A.; Kloosterman, J.B.; Lechler, P.; Mayewski, P.A.; Montgomery, J.; Porede, R.; Darrah, T.; Que Hee, S.S.; Smith, A.R.; Stich, A.; Topping, W.; Wittke, J.H.; Wolbach, W.S.

    2007-01-01

    A carbon-rich black layer, dating to ∼12.9 ka, has been previously identified at ∼50 Clovis-age sites across North America and appears contemporaneous with the abrupt onset of Younger Dryas (YD) cooling. The in situ bones of extinct Pleistocene megafauna and Clovistool assemblages occur below this black layer but not within or above it. Causes for the extinctions, the YD cooling, and the termination of Clovisculture have long been controversial. In this paper, we provide evidence for an extraterrestrial (ET) impact event at ?12.9 ka, which, we hypothesize, caused abrupt environmental changes that contributed to YD cooling, major ecological reorganization, broad-scale extinctions, and rapid human behavioral shifts at the end of the Clovis Period. Clovis-age sites in North American are overlain by a thin, discrete layer with varying peak abundances of: (1) magnetic grains with iridium, (2) magnetic microspherules (3) charcoal, (4) soot, (5) carbon spherules, (6) glass-like carbon, and (7) fullerenes with ET helium, all of which are evidence for an ET impact and associated biomass burning at ∼12.9 ka.This layer also extends throughout at least fifteen Carolina Bays, which are unique, elliptical wetlands, oriented to the northwest across the Atlantic Coastal Plain. We propose that one or more large, low-density ET objects exploded over northern North America, partially destabilizing the Laurentide Ice Sheet and triggering YD cooling. The shock wave, thermal pulse, and event-related environmental effects (e.g., extensive biomass burning, food limitations) contributed to the end-Pleistocene megafaunal extinctions and adaptive shifts among PaleoAmericans in North America

  15. Geological events and Pliocene climate fluctuations explain the phylogeographical pattern of the cold water fish Rhynchocypris oxycephalus (Cypriniformes: Cyprinidae) in China.

    Science.gov (United States)

    Yu, Dan; Chen, Ming; Tang, Qiongying; Li, Xiaojuan; Liu, Huanzhang

    2014-10-25

    Rhynchocypris oxycephalus is a cold water fish with a wide geographic distribution including the relatively warm temperate regions of southern China. It also occurs in second- and third-step geomorphic areas in China. Previous studies have postulated that high-altitude populations of R. oxycephalus in southern China are Quaternary glacial relics. In this study, we used the mitochondrial gene Cytb and the nuclear gene RAG2 to investigate the species phylogeographical patterns and to test two biogeographic hypotheses: (1) that divergence between lineages supports the three-step model and (2) climatic fluctuations during the Quaternary resulted in the present distribution in southern China. Phylogenetic analysis detected three major matrilines (A, B, and C); with matrilines B and C being further subdivided into two submatrilines. Based on genetic distances and morphological differences, matriline A potentially represents a cryptic subspecies. The geographic division between matrilines B and C coincided with the division of the second and third geomorphic steps in China, suggesting a historical vicariance event. Pliocene climatic fluctuations might have facilitated the southwards dispersal of R. oxycephalus in matriline C, with the subsequent warming resulting in its split into submatrilines C1 and C2, leaving submatriline C2 as a relic in southern China. Our study demonstrates that geological events (three steps orogenesis) and climate fluctuations during the Pliocene were important factors in shaping phylogeographical patterns in R. oxycephalus. Notably, no genetic diversity was detected in several populations, all of which possessed unique genotypes. This indicates the uniqueness of local populations and calls for a special conservation plan for the whole species at the population level.

  16. Sediment of a Central European Mountain Lake Implies an Extraterrestrial Impact at the Younger Dryas Onset

    Czech Academy of Sciences Publication Activity Database

    Vondrák, D.; Kletetschka, G.; Hrubá, J.; Nábělek, L.; Procházka, V.; Svitavská-Svobodová, Helena; Bobek, Přemysl; Hořická, Zuzana; Kadlec, Jaroslav; Takáč, M.; Stuchlík, Evžen

    2017-01-01

    Roč. 52, S1 (2017), A373-A373, č. článku 6230. ISSN 1086-9379. [Annual Meeting of the Meteoritical Society /80./. 23.07.2017-28.07.2017, Santa Fe] R&D Projects: GA ČR(CZ) GA17-05935S Institutional support: RVO:67985939 ; RVO:60077344 ; RVO:67985530 Keywords : Younger Dryas * Extraterrestrial Impact * Central Europe Subject RIV: DG - Athmosphere Sciences, Meteorology; DA - Hydrology ; Limnology (BC-A); DE - Earth Magnetism, Geodesy, Geography (GFU-E) OBOR OECD: Plant sciences, botany

  17. Microspherules in the Sediment from the Onset of Younger Dryas; Airburst and/or Volcanic Explosion

    Czech Academy of Sciences Publication Activity Database

    Kletetschka, Günther; Hrubá, J.; Nábělek, Ladislav; West, A.; Vondrák, D.; Stuchlík, Evžen; Kadlec, Jaroslav; Procházka, V.

    2017-01-01

    Roč. 52, SI 1 (2017), A169 ISSN 1086-9379. [Annual Meeting of the Meteoritical Society /80./. 23.07.2017-28.07.2017, Santa Fe] R&D Projects: GA ČR(CZ) GA17-05935S Institutional support: RVO:67985831 ; RVO:60077344 ; RVO:67985530 Keywords : microspherules * volcanic explosion * Younger Dryas * sediments Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics; DA - Hydrology ; Limnology (BC-A) http://onlinelibrary.wiley.com/doi/10.1111/maps.2017.52.issue-S1/issuetoc

  18. Younger Dryas Boundary (YDB) impact : physical and statistical impossibility.

    Energy Technology Data Exchange (ETDEWEB)

    Boslough, Mark Bruce Elrick

    2010-08-01

    The YDB impact hypothesis of Firestone et al. (2007) is so extremely improbable it can be considered statistically impossible in addition to being physically impossible. Comets make up only about 1% of the population of Earth-crossing objects. Broken comets are a vanishingly small fraction, and only exist as Earth-sized clusters for a very short period of time. Only a small fraction of impacts occur at angles as shallow as proposed by the YDB impact authors. Events that are exceptionally unlikely to take place in the age of the Universe are 'statistically impossible'. The size distribution of Earth-crossing asteroids is well-constrained by astronomical observations, DoD satellite bolide frequencies, and the cratering record. This distribution can be transformed to a probability density function (PDF) for the largest expected impact of the past 20,000 years. The largest impact of any kind expected over the period of interest is 250 m. Anything larger than 2 km is exceptionally unlikely (probability less than 1%). The impact hypothesis does not rely on any sound physical model. A 4-km diameter comet, even if it fragmented upon entry, would not disperse or explode in the atmosphere. It would generate a crater about 50 km in diameter with a transient cavity as deep as 10 km. There is no evidence for such a large, young crater associated with the YDB. There is no model to suggest that a comet impact of this size is capable of generating continental-wide fires or blast damage, and there is no physical mechanism that could cause a 4-km comet to explode at the optimum height of 500 km. The highest possible altitude for a cometary optimum height is about 15 km, for a 120-m diameter comet. To maximize blast and thermal damage, a 4-km comet would have to break into tens of thousands fragments of this size and spread out over the entire continent, but that would require lateral forces that greatly exceed the drag force, and would not conserve energy. Airbursts are

  19. Bayesian chronological analyses consistent with synchronous age of 12,835-12,735 Cal B.P. for Younger Dryas boundary on four continents

    DEFF Research Database (Denmark)

    Kennett, James P.; Kennett, Douglas J.; Culleton, Brendan J.

    2015-01-01

    The Younger Dryas impact hypothesis posits that a cosmic impact across much of the Northern Hemisphere deposited the Younger Dryas boundary (YDB) layer, containing peak abundances in a variable assemblage of proxies, including magnetic and glassy impact-related spherules, high-temperature mineral...

  20. Identification of contrasting seasonal sea ice conditions during the Younger Dryas

    Science.gov (United States)

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

    2012-12-01

    The presence of the sea ice diatom biomarker IP25 in Arctic marine sediments has been used in previous studies 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. 1, 2]. The current study focuses on high-resolution palaeo sea ice reconstructions for northern Norway during the last ca. 15 cal. kyr BP. Within this study, particular emphasis has been placed on the identification of the sea ice conditions during the Younger Dryas and the application of different biomarker-based proxies to both identify and quantify seasonal sea ice conditions. Firstly, the appearance of the specific sea ice diatom proxy IP25 at ca. 12.9 cal. kyr BP in a marine sediment core (JM99-1200) obtained from Andfjorden has provided an unambiguous but qualitative measure of seasonal sea ice and thus the onset of the Younger Dryas stadial. The near continuous occurrence of IP25 for the next ca. 1400 yr demonstrates seasonal sea ice during this interval, although variable abundances suggest that the recurrent conditions in the early-mid Younger Dryas (ca. 12.9 - 11.9 cal. kyr BP) changed significantly from stable to highly variable sea ice conditions at ca. 11.9 cal. kyr BP and this instability in sea ice prevailed for the subsequent ca. 400 yr. At ca. 11.5 cal. kyr BP, IP25 disappeared from the record indicating ice-free conditions that signified the beginning of the Holocene. Similarly, a high resolution record from the Kveithola Through, western Barents Sea, showed clearly higher IP25 concentrations during the Younger Dryas stadial compared to the Holocene. For both marine records, the IP25 concentrations were also combined with those of the open water phytoplankton biomarker brassicasterol to generate PBIP25 data from which more quantitative measurements of sea ice were determined. The contrasting seasonal sea ice conditions during the Younger Dryas were further verified

  1. Reply to Ives and Froese: Regarding the impact-related Younger Dryas boundary layer at Chobot site, Alberta, Canada

    Czech Academy of Sciences Publication Activity Database

    Wittke, J. H.; Bunch, T. E.; Tankersley, K. B.; Daniel Jr., I. R.; Kloosterman, J. B.; Kletetschka, Günther; West, A.; Firestone, R. B.

    2013-01-01

    Roč. 110, č. 41 (2013), E3900-E3900 ISSN 0027-8424 Institutional support: RVO:67985831 Keywords : Younger Dryas boundary * charcoal * black mat Subject RIV: DN - Health Impact of the Environment Quality Impact factor: 9.809, year: 2013

  2. Rapid response of alpine timberline vegetation to the Younger Dryas climate oscillation in the Colorado Rocky Mountains, USA

    International Nuclear Information System (INIS)

    Reasoner, M.A.; Jodry, M.A.

    2000-01-01

    Paleobotanical records from two high-altitude (>3,300 m) sites in Colorado show a clear and immediate response to the Younger Dryas climate oscillation. The Black Mountain Lake and Sky Pond records indicate that alpine timberline migrated upslope to near-modern elevations during the late Bolling-Allerod (13.6--12.9 ka). Subsequent declines in arboreal pollen percentages and accumulation rates during the Younger Dryas interval (12.9--11.7 ka) reflect a downslope displacement of the alpine timberline ecotone of 60--120 m in elevation. This change translates to a cooling of summer temperature by ∼0.4--0.9 C and is consistent with proposed Younger Dryas advances of alpine glaciers in the Rocky Mountains to positions close to Little Ice Age maxima. Alpine timberline readvanced upslope to elevations above both sites between 11.7 and 11.4 ka. The concomitant response of temperature-sensitive alpine timberline vegetation in Colorado and late-glacial changes in North Atlantic thermohaline circulating implicates a rapid, widespread atmospheric transmission of the Younger Dryas climate oscillation

  3. Rapid response of alpine timberline vegetation to the Younger Dryas climate oscillation in the Colorado Rocky Mountains, USA

    Energy Technology Data Exchange (ETDEWEB)

    Reasoner, M.A.; Jodry, M.A.

    2000-01-01

    Paleobotanical records from two high-altitude (>3,300 m) sites in Colorado show a clear and immediate response to the Younger Dryas climate oscillation. The Black Mountain Lake and Sky Pond records indicate that alpine timberline migrated upslope to near-modern elevations during the late Bolling-Allerod (13.6--12.9 ka). Subsequent declines in arboreal pollen percentages and accumulation rates during the Younger Dryas interval (12.9--11.7 ka) reflect a downslope displacement of the alpine timberline ecotone of 60--120 m in elevation. This change translates to a cooling of summer temperature by {approximately}0.4--0.9 C and is consistent with proposed Younger Dryas advances of alpine glaciers in the Rocky Mountains to positions close to Little Ice Age maxima. Alpine timberline readvanced upslope to elevations above both sites between 11.7 and 11.4 ka. The concomitant response of temperature-sensitive alpine timberline vegetation in Colorado and late-glacial changes in North Atlantic thermohaline circulating implicates a rapid, widespread atmospheric transmission of the Younger Dryas climate oscillation.

  4. Younger-Dryas cooling and sea-ice feedbacks were prominent features of the Pleistocene-Holocene transition in Arctic Alaska

    Science.gov (United States)

    Gaglioti, Benjamin V.; Mann, Daniel H.; Wooller, Matthew J.; Jones, Benjamin M.; Wiles, Gregory C.; Groves, Pamela; Kunz, Michael L.; Baughman, Carson A.; Reanier, Richard E.

    2017-08-01

    Declining sea-ice extent is currently amplifying climate warming in the Arctic. Instrumental records at high latitudes are too short-term to provide sufficient historical context for these trends, so paleoclimate archives are needed to better understand the functioning of the sea ice-albedo feedback. Here we use the oxygen isotope values of wood cellulose in living and sub-fossil willow shrubs (δ18Owc) (Salix spp.) that have been radiocarbon-dated (14C) to produce a multi-millennial record of climatic change on Alaska's North Slope during the Pleistocene-Holocene transition (13,500-7500 calibrated 14C years before present; 13.5-7.5 ka). We first analyzed the spatial and temporal patterns of δ18Owc in living willows growing at upland sites and found that over the last 30 years δ18Owc values in individual growth rings correlate with local summer temperature and inter-annual variations in summer sea-ice extent. Deglacial δ18Owc values from 145 samples of subfossil willows clearly record the Allerød warm period (∼13.2 ka), the Younger Dryas cold period (12.9-11.7 ka), and the Holocene Thermal Maximum (11.7-9.0 ka). The magnitudes of isotopic changes over these rapid climate oscillations were ∼4.5‰, which is about 60% of the differences in δ18Owc between those willows growing during the last glacial period and today. Modeling of isotope-precipitation relationships based on Rayleigh distillation processes suggests that during the Younger Dryas these large shifts in δ18Owc values were caused by interactions between local temperature and changes in evaporative moisture sources, the latter controlled by sea ice extent in the Arctic Ocean and Bering Sea. Based on these results and on the effects that sea-ice have on climate today, we infer that ocean-derived feedbacks amplified temperature changes and enhanced precipitation in coastal regions of Arctic Alaska during warm times in the past. Today, isotope values in willows on the North Slope of Alaska are similar

  5. Younger-Dryas cooling and sea-ice feedbacks were prominent features of the Pleistocene-Holocene transition in Arctic Alaska

    Science.gov (United States)

    Gaglioti, Benjamin V.; Mann, Daniel H.; Wooller, Matthew J.; Jones, Benjamin M.; Wiles, Gregory C.; Groves, Pamela; Kunz, Michael L.; Baughman, Carson; Reanier, Richard E.

    2017-01-01

    Declining sea-ice extent is currently amplifying climate warming in the Arctic. Instrumental records at high latitudes are too short-term to provide sufficient historical context for these trends, so paleoclimate archives are needed to better understand the functioning of the sea ice-albedo feedback. Here we use the oxygen isotope values of wood cellulose in living and sub-fossil willow shrubs (δ18Owc) (Salix spp.) that have been radiocarbon-dated (14C) to produce a multi-millennial record of climatic change on Alaska's North Slope during the Pleistocene-Holocene transition (13,500–7500 calibrated 14C years before present; 13.5–7.5 ka). We first analyzed the spatial and temporal patterns of δ18Owc in living willows growing at upland sites and found that over the last 30 years δ18Owc values in individual growth rings correlate with local summer temperature and inter-annual variations in summer sea-ice extent. Deglacial δ18Owcvalues from 145 samples of subfossil willows clearly record the Allerød warm period (∼13.2 ka), the Younger Dryas cold period (12.9–11.7 ka), and the Holocene Thermal Maximum (11.7–9.0 ka). The magnitudes of isotopic changes over these rapid climate oscillations were ∼4.5‰, which is about 60% of the differences in δ18Owc between those willows growing during the last glacial period and today. Modeling of isotope-precipitation relationships based on Rayleigh distillation processes suggests that during the Younger Dryas these large shifts in δ18Owc values were caused by interactions between local temperature and changes in evaporative moisture sources, the latter controlled by seaice extent in the Arctic Ocean and Bering Sea. Based on these results and on the effects that sea-ice have on climate today, we infer that ocean-derived feedbacks amplified temperature changes and enhanced precipitation in coastal regions of Arctic Alaska during warm times in the past. Today, isotope values in willows on the North Slope of Alaska are

  6. A new concept for paleohydrological evolution of the Younger Dryas in NE Brazil

    Science.gov (United States)

    Bouimetarhan, Ilham; Prange, Matthias; Gonzalez, Catalina; Dupont, Lydie

    2016-04-01

    The late deglacial interval from approximately 13 to 11 kyr BP contains some of the best documented abrupt climate changes in the Past, the Younger Dryas (YD). It is also an interval when the bipolar climatic signature of millennial-scale changes in the Atlantic meridional overturning circulation (AMOC) is well expressed. Here we present a high-resolution palynological record from core GeoB16205-4 (1°21.11'N, 43°05.80'W), retrieved off the Parnaíba River mouth, southeast of the Amazon River (~1955 m water depth). Pollen and organic-walled dinoflagellate cyst assemblages indicate a predominantly wet climate during the YD in the nowadays semi-arid Nordeste, whereby a second phase between ~12.3 and 11.7 kyr BP is wetter than the period before. This is recorded by a strong increase in the concentrations of river plume dinoflagellate cyst assemblages indicative of a stratified surface water column and reduced salinity environments, as well as a drop in grass pollen and microcharcoal particle concentrations along with strong fluctuations in the representation of rain forest, gallery forest and tree ferns suggesting year-round humid conditions. This shift from a relatively wet first phase to a much wetter second phase is in agreement with the transient TRACE-21k coupled climate model simulation which shows a first pluvial Parnaíba stage from ~12.8 to 12.3 kyr BP and a second stronger pluvial stage between ~12.3 and 11.7 kyr BP to be related to a very weak AMOC due to meltwater pulses in the North Atlantic. The AMOC variation induces a steep temperature gradient between the Southern and the Northern Hemisphere which forces a southward shift of the Intertropical Convergence Zone (ITCZ) and its associated rainfall. The two-step hydroclimatic and environmental evolution during the Younger Dryas has not been documented previously in this region.

  7. Cold plate

    Energy Technology Data Exchange (ETDEWEB)

    Marroquin, Christopher M.; O' Connell, Kevin M.; Schultz, Mark D.; Tian, Shurong

    2018-02-13

    A cold plate, an electronic assembly including a cold plate, and a method for forming a cold plate are provided. The cold plate includes an interface plate and an opposing plate that form a plenum. The cold plate includes a plurality of active areas arranged for alignment over respective heat generating portions of an electronic assembly, and non-active areas between the active areas. A cooling fluid flows through the plenum. The plenum, at the non-active areas, has a reduced width and/or reduced height relative to the plenum at the active areas. The reduced width and/or height of the plenum, and exterior dimensions of cold plate, at the non-active areas allow the non-active areas to flex to accommodate surface variations of the electronics assembly. The reduced width and/or height non-active areas can be specifically shaped to fit between physical features of the electronics assembly.

  8. Gymnodinium corollarium sp. nov. (Dinophyceae) - a new cold-water dinoflagellate responsible for cyst sedimentation events in the Baltic Sea

    DEFF Research Database (Denmark)

    Sundström, Annica; Kremp, Anke; Daugbjerg, Niels

    2009-01-01

    revealed a preference of G. corollarium for low salinities and temperatures, confirming it to be a cold-water species well adapted to the brackish water conditions in the Baltic Sea. At nitrogen-deplete conditions, G. corollarium cultures produced small, slightly oval cysts resembling a previously...

  9. Pulleniatina Minimum Events in the Andaman Sea (NE Indian Ocean): Implications for winter monsoon and thermocline changes

    Digital Repository Service at National Institute of Oceanography (India)

    Sijinkumar, A.V.; Nath, B.N.; Possnert, G.; Aldahan, A.

    abundance, and which matches well with the Pacific records influenced by the Kuroshio Current. Additionally, two significant minimum events of P. obliquiloculata are also seen during the Younger Dryas (YD) and late Last Glacial Maximum (LGM, 20-18 cal ka... (LGM, 20-18 cal ka BP, Younger Dryas (YD, 13-10.5 cal ka BP) and late Holocene (4.5-3 cal ka BP). Northern core SK 168 shows distinctive minimum events and the intensity of variation reduces towards the south. The Holocene PME is a little longer...

  10. Cold injuries.

    Science.gov (United States)

    Kruse, R J

    1995-01-01

    There are two categories of cold injury. The first is hypothermia, which is a systemic injury to cold, and the second is frostbite, which is a local injury. Throughout history, entire armies, from George Washington to the Germans on the Russian Front in World War II, have fallen prey to prolonged cold exposure. Cold injury is common and can occur in all seasons if ambient temperature is lower than the core body temperature. In the 1985 Boston Marathon, even though it was 76 degrees and sunny, there were 75 runners treated for hypothermia. In general, humans adapt poorly to cold exposure. Children are at particular risk because of their relatively greater surface area/body mass ratio, causing them to cool even more rapidly than adults. Because of this, the human's best defense against cold injury is to limit his/her exposure to cold and to dress appropriately. If cold injury has occurred and is mild, often simple passive rewarming such as dry blankets and a warm room are sufficient treatment.

  11. Late Pleistocene Megafaunal Extinction Consistent With YDB Impact Hypothesis at Younger Dryas Onset

    Science.gov (United States)

    Kennett, J. P.; Kennett, D. J.

    2008-12-01

    At least 35 mammal and 19 bird genera became extinct across North America near the end of the Pleistocene. Modern increases in stratigraphic and dating resolution suggest that this extinction occurred relatively rapidly near 12.9 ka (11 radiocarbon kyrs). Within the context of a long-standing debate about its cause, Firestone et al., (2007) proposed that this extinction resulted from an extraterrestrial (ET) impact over North America at 12.9 ka. This hypothesis predicts that the extinction of most of these animals should have occurred abruptly at 12.9 ka. To test this hypothesis, we have critically examined radiocarbon ages and the extinction stratigraphy of these taxa. From a large data pool, we selected only radiocarbon dates with low error margins with a preference for directly dated biological materials (e.g., bone, dung, etc.) and modern chemical purification techniques. A relatively small number of acceptable dates indicate that at least 16 animal genera and several other species became extinct close to 12.9 ka. These taxa include the most common animals of the late Pleistocene such as horses, camels, and mammoths. Also, the remains of extinct taxa are reportedly found up to, but not above, the base of a widely distributed carbon-rich layer called the black mat. This stratum forms an abrupt, major biostratigraphic boundary at the Younger Dryas onset (12.9 ka), which also contains multiple ET markers comprising the impact layer (the YDB). Surviving animal populations were abruptly reduced at the YDB (e.g., Bison), with major range restrictions and apparent evolutionary bottlenecks. The abruptness of this major extinction is inconsistent with the hypotheses of human overkill and climatic change. We argue that extinction ages older than 12.9 ka for many less common species result from the Signor-Lipps effect, but the impact hypothesis predicts that as new dates are acquired, they will approach ever closer to 12.9 ka. The megafaunal extinction is strongly

  12. Climate Reconstructions of the Younger Dryas: An ELA Model Investigating Variability in ELA Depressions, Temperature, and Precipitation Changes for the Graubϋnden Alps

    Science.gov (United States)

    Keeler, D. G.; Rupper, S.; Schaefer, J. M.; Finkel, R. C.

    2015-12-01

    The high sensitivity of mountain glaciers to even small perturbations in climate, combined with a near global distribution, make alpine glaciers an important target for terrestrial paleoclimate reconstructions. The geomorphic remnant of past glaciers can yield important insights into past climate, particularly in regions where other methods of reconstruction are not possible. The quantitative conversion of these changes in geomorphology to a climate signal, however, presents a significant challenge. A particular need exists for a versatile climate reconstruction method applicable to diverse glacierized regions around the globe. Because the glacier equilibrium line altitude (ELA) provides a more explicit comparison of climate than properties such as glacier length or area, ELA methods lend themselves well to such a need, and allow for a more direct investigation of the primary drivers of mountain glaciations during specific events. Here, we present an ELA model for quantifying changes in climate based on changes in glacier extent, while accounting for differences in glacier width, glacier shape, bed topography, ice thickness, and glacier length. The model furthermore provides bounds on the ΔELA using Monte Carlo simulations. These methods are validated using published mass balances and ELA measurements from 4 modern glaciers in the European Alps. We then use this ELA model, combined with a surface mass and energy balance model, to estimate the changes in temperature/precipitation between the Younger Dryas (constrained by 10Be surface exposure ages) and the present day for three glacier systems in the Graubϋnden Alps. Our results indicate an ELA depression in this area of 257 m ±45 m during the Younger Dryas (YD) relative to today. This corresponds to a 1.3 °C ±0.36 °C decrease in temperature or a 156% ±30% increase in precipitation relative to today. These results indicate the likelihood of a predominantly temperature-driven change rather than a strong

  13. Cold Sore

    Science.gov (United States)

    ... may reduce how often they return. Symptoms A cold sore usually passes through several stages: Tingling and itching. Many people feel an itching, burning or tingling sensation around their lips for a day or so ...

  14. Millennial-scale precipitation variability over Easter Island (South Pacific) during MIS 3: inter-hemispheric teleconnections with North Atlantic abrupt cold events

    Science.gov (United States)

    Margalef, O.; Cacho, I.; Pla-Rabes, S.; Cañellas-Boltà, N.; Pueyo, J. J.; Sáez, A.; Pena, L. D.; Valero-Garcés, B. L.; Rull, V.; Giralt, S.

    2015-04-01

    Marine Isotope Stage 3 (MIS 3, 59.4-27.8 kyr BP) is characterized by the occurrence of rapid millennial-scale climate oscillations known as Dansgaard-Oeschger cycles (DO) and by abrupt cooling events in the North Atlantic known as Heinrich events. Although both the timing and dynamics of these events have been broadly explored in North Atlantic records, the response of the tropical and subtropical latitudes to these rapid climatic excursions, particularly in the Southern Hemisphere, still remains unclear. The Rano Aroi peat record (Easter Island, 27° S) provides a unique opportunity to understand atmospheric and oceanic changes in the South Pacific during these DO cycles because of its singular location, which is influenced by the South Pacific Anticyclone (SPA), the Southern Westerlies (SW), and the Intertropical Convergence Zone (ITCZ) linked to the South Pacific Convergence Zone (SPCZ). The Rano Aroi sequence records 6 major events of enhanced precipitation between 38 and 65 kyr BP. These events are compared with other hydrological records from the tropical and subtropical band supporting a coherent regional picture, with the dominance of humid conditions in Southern Hemisphere tropical band during Heinrich Stadials (HS) 5, 5a and 6 and other Stadials while dry conditions prevailed in the Northern tropics. This antiphased hydrological pattern between hemispheres has been attributed to ITCZ migration, which in turn might be associated with an eastward expansion of the SPCZ storm track, leading to an increased intensity of cyclogenic storms reaching Easter Island. Low Pacific Sea Surface Temperature (SST) gradients across the Equator were coincident with the here-defined Rano Aroi humid events and consistent with a reorganization of Southern Pacific atmospheric and oceanic circulation also at higher latitudes during Heinrich and Dansgaard-Oeschger stadials.

  15. GYMNODINIUM COROLLARIUM SP. NOV. (DINOPHYCEAE)-A NEW COLD-WATER DINOFLAGELLATE RESPONSIBLE FOR CYST SEDIMENTATION EVENTS IN THE BALTIC SEA(1).

    Science.gov (United States)

    Sundström, Annica M; Kremp, Anke; Daugbjerg, Niels; Moestrup, Øjvind; Ellegaard, Marianne; Hansen, Regina; Hajdu, Susanna

    2009-08-01

    A naked dinoflagellate with a unique arrangement of chloroplasts in the center of the cell was isolated from the northern Baltic proper during a spring dinoflagellate bloom (March 2005). Morphological, ultrastructural, and molecular analyses revealed this dinoflagellate to be undescribed and belonging to the genus Gymnodinium F. Stein. Gymnodinium corollarium A. M. Sundström, Kremp et Daugbjerg sp. nov. possesses features typical of Gymnodinium sensu stricto, such as nuclear chambers and an apical groove running in a counterclockwise direction around the apex. Phylogenetic analyses based on partial nuclear-encoded LSU rDNA sequences place the species in close proximity to G. aureolum, but significant genetic distance, together with distinct morphological features, such as the position of chloroplasts, clearly justifies separation from this species. Temperature and salinity experiments revealed a preference of G. corollarium for low salinities and temperatures, confirming it to be a cold-water species well adapted to the brackish water conditions in the Baltic Sea. At nitrogen-deplete conditions, G. corollarium cultures produced small, slightly oval cysts resembling a previously unidentified cyst type commonly found in sediment trap samples collected from the northern and central open Baltic Sea. Based on LSU rDNA comparison, these cysts were assigned to G. corollarium. The cysts have been observed in many parts of the Baltic Sea, indicating the ecologic versatility of the species and its importance for the Baltic ecosystem. © 2009 Phycological Society of America.

  16. Cold fusion

    International Nuclear Information System (INIS)

    Koster, J.

    1989-01-01

    In this contribution the author the phenomenom of so-called cold fusion, inspired by the memorable lecture of Moshe Gai on his own search for this effect. Thus much of what follows was presented by Dr. Gai; the rest is from independent reading. What is referred to as cold fusion is of course the observation of possible products of deuteron-deuteron (d-d) fusion within deuterium-loaded (dentended) electrodes. The debate over the two vanguard cold fusion experiments has raged under far more public attention than usually accorded new scientific phenomena. The clamor commenced with the press conference of M. Fleishmann and S. Pons on March 23, 1989 and the nearly simultaneous wide circulation of a preprint of S. Jones and collaborators. The majority of work attempting to confirm these observations has at the time of this writing yet to appear in published form, but contributions to conferences and electronic mail over computer networks were certainly filled with preliminary results. To keep what follows to a reasonable length the author limit this discussion to the searches for neutron (suggested by ref. 2) or for excessive heat production (suggested by ref. 1), following a synopsis of the hypotheses of cold fusion

  17. Project COLD.

    Science.gov (United States)

    Kazanjian, Wendy C.

    1982-01-01

    Describes Project COLD (Climate, Ocean, Land, Discovery) a scientific study of the Polar Regions, a collection of 35 modules used within the framework of existing subjects: oceanography, biology, geology, meterology, geography, social science. Includes a partial list of topics and one activity (geodesic dome) from a module. (Author/SK)

  18. Cold fusion

    International Nuclear Information System (INIS)

    Seo, Suk Yong; You, Jae Jun

    1996-01-01

    Nearly every technical information is chased in the world. All of them are reviewed and analyzed. Some of them are chosen to study further more to review every related documents. And a probable suggestion about the excitonic process in deuteron absorbed condensed matter is proposed a way to cold fusion. 8 refs. (Author)

  19. Regional scale climatic trends derived from Younger Dryas glaciers in the U.K.

    Science.gov (United States)

    Pearce, D.; Rea, B. R.; Barr, I.; Small, D.; McDougall, D.

    2014-12-01

    In the U.K., the glacial geomorphological record has been utilised to infer paleo-glacier geometries and ice dynamics, with much of this work focussing on the Scottish Highlands during the Younger Dryas (YD; c. 12.9 - 11.7 ka BP). During the YD the West Highlands Ice-cap covered the majority of the Scottish Highlands (c. 13,000 sq mi), which is thought to have affected accumulation rates beyond the ice-cap margins, resulting in a steep (c. 80%) easterly decline in precipitation and smaller ice-masses. We present multi-proxy data investigating YD glaciation in the Tweedsmuir Hills, Southern Uplands, Scotland (55°46' N, 03°34' W), suggesting conditions were less arid. The area forms the most easterly upland region in the Southern Uplands and south of the West Highlands Ice-cap, reaching an altitude of 840 m and covering c. 200 sq mi. Results of air-photo interpretation and field mapping, which utilised a morphostratigraphic approach, have demonstrated a more extensive glaciation than previously mapped. The reconstruction consists of two separate icefields covering an area c. 40 sq mi. and new 14C dates of basal contact organics place the ice-mass within the context of the YD but new Cosmogenic Nuclide Analysis (CNA) of bedrock and in situ boulders are inconclusive, implying limited erosion and limited resetting during the YD. Equilibrium Line Altitudes are calculated to have ranged from c. 419 - 634 m. Paleo-precipitation values were derived using two precipitation-temperature relationships and suggest slightly lower totals than YD ice-masses located on the west coast of the U.K. but do not support a significant easterly reduction in precipitation. Analysis of present-day (c. 30 year) meteorological data across the U.K. demonstrates a pronounced reduction in precipitation of c. 50% on the east coast. This disparity between present-day and glacier-based YD precipitation patterns is partly attributable to the methodology employed in glacier reconstruction and

  20. Quartz microstructures in the Younger Dryas boundary layer ~12.9 ka.

    Science.gov (United States)

    van Hoesel, A.; Hoek, W. Z.; Pennock, G. M.; Drury, M. R.

    2012-04-01

    In 2007, Firestone et al. proposed that an extraterrestrial impact occurred at the end of the Allerød interstadial, destabilizing the North American ice sheet and initiating the colder Younger Dryas (YD) stadial. Up to now, the evidence for this proposed impact has been heavily debated (Pinter et al., 2011) and no one has been able to provide convincing evidence in favour of the hypothesis. Two years later, Mahaney et al. (2009) claimed that they had frequently found planar deformation features (PDFs) in quartz from a possible YD boundary layer in Venezuela. However, the data presented consisted of an SEM image of the surface of a quartz grain only, and in following work Mahaney et al. (2010) stated that they had found no irrefutable evidence of PDFs. Instead, they showed grains with oriented cracks along their edges, which they claimed to be related to the 'mass impact and extreme heat' from incoming ejecta material. However, oriented cracks are not accepted evidence for an impact (French, Koeberl, 2010). We investigate the quartz fraction of samples from the European Usselo horizon, an Allerød-YD age soil, as well as one sample from the North American Black Mat, which marks the onset of the YD. Possible shocked quartz grains were isolated using density separation, mounted in epoxy and polished. No evidence for oriented cracks along grain edges, like those reported by Mahaney et al. (2010), has been found so far. Transmitted light microscopy showed that a number of grains contained tectonic deformation lamellae. One grain from the Usselo horizon contains at least two sets of closely spaced, straight, and narrow lamellae, similar to PDFs. In SEM-CL imaging however, only some of these lamellae showed up as non-luminescent, while most had the same intensity as the host grain. This is not typical for PDFs (Hamers, Drury 2011). It is possible that these lamellae represent planar fractures, which also form by low pressure shock processes. It must be noted that even if

  1. Cold fusion

    International Nuclear Information System (INIS)

    Suh, Suk Yong; Sung, Ki Woong; Kang, Joo Sang; Lee, Jong Jik

    1995-02-01

    So called 'cold fusion phenomena' are not confirmed yet. Excess heat generation is very delicate one. Neutron generation is most reliable results, however, the records are erratic and the same results could not be repeated. So there is no reason to exclude the malfunction of testing instruments. The same arguments arise in recording 4 He, 3 He, 3 H, which are not rich in quantity basically. An experiment where plenty of 4 He were recorded is attached in appendix. The problem is that we are trying to search cold fusion which is permitted by nature or not. The famous tunneling effect in quantum mechanics will answer it, however, the most fusion rate is known to be negligible. The focus of this project is on the theme that how to increase that negligible fusion rate. 6 figs, 4 tabs, 1512 refs. (Author)

  2. Cold fusion

    Energy Technology Data Exchange (ETDEWEB)

    Suh, Suk Yong; Sung, Ki Woong; Kang, Joo Sang; Lee, Jong Jik [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1995-02-01

    So called `cold fusion phenomena` are not confirmed yet. Excess heat generation is very delicate one. Neutron generation is most reliable results, however, the records are erratic and the same results could not be repeated. So there is no reason to exclude the malfunction of testing instruments. The same arguments arise in recording {sup 4}He, {sup 3}He, {sup 3}H, which are not rich in quantity basically. An experiment where plenty of {sup 4}He were recorded is attached in appendix. The problem is that we are trying to search cold fusion which is permitted by nature or not. The famous tunneling effect in quantum mechanics will answer it, however, the most fusion rate is known to be negligible. The focus of this project is on the theme that how to increase that negligible fusion rate. 6 figs, 4 tabs, 1512 refs. (Author).

  3. Extraordinary Biomass-Burning Episode and Impact Winter Triggered by the Younger Dryas Cosmic Impact approximate to 12,800 Years Ago. 2. Lake, Marine, and Terrestrial Sediments

    Czech Academy of Sciences Publication Activity Database

    Wolbach, W. S.; Ballard, J. P.; Mayewski, P. A.; Parnell, A. C.; Cahill, N.; Adedeji, V.; Bunch, T. E.; Dominguez-Vazquez, G.; Erlandson, J. M.; Firestone, R. B.; French, T. A.; Howard, G.; Israde-Alcántara, I.; Johnson, J. R.; Kimbel, D.; Kinzie, Ch. R.; Kurbatov, A.; Kletetschka, Günther; LeCompte, M. A.; Mahaney, W. C.; Mellot, A. L.; Mitra, S.; Maiorana-Boutilier, A.; Moore, Ch. R.; Napier, W. M.; Parlier, J.; Tankersley, K. B.; Thomas, B. C.; Wittke, J. H.; West, A.; Kennett, J. P.

    2018-01-01

    Roč. 126, č. 2 (2018), s. 185-205 ISSN 0022-1376 Institutional support: RVO:67985831 Keywords : biomass burning * climate feedback * climate variation * ice core * lacustrine deposit * marine sediment * paleoclimate * quantitative analysis * terrestrial deposit * winter * Younger Dryas Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Geology Impact factor: 1.952, year: 2016

  4. Extraordinary Biomass-Burning Episode and Impact Winter Triggered by the Younger Dryas Cosmic Impact approximate to 12,800 Years Ago. 1. Ice Cores and Glaciers

    Czech Academy of Sciences Publication Activity Database

    Wolbach, W. S.; Ballard, J. P.; Mayewski, P. A.; Adedeji, V.; Bunch, T. E.; Firestone, R. B.; French, T. A.; Howard, G. A.; Israde-Alcántara, I.; Johnson, J. R.; Kimbel, D. R.; Kinzie, Ch. R.; Kurbatov, A.; Kletetschka, Günther; LeCompte, M. A.; Mahaney, W. C.; Mellot, A. L.; Maiorana-Boutilier, A.; Mitra, S.; Moore, Ch. R.; Napier, W. M.; Parlier, J.; Tankersley, K. B.; Thomas, B. C.; Wittke, J. H.; West, A.; Kennett, J. P.

    2018-01-01

    Roč. 126, č. 2 (2018), s. 165-184 ISSN 0022-1376 Institutional support: RVO:67985831 Keywords : biomass burning * comet * deposition * ice core * impact * mass extinction * paleoclimate * paleoenvironment * platinum * trigger mechanism * wildfire * winter * Younger Dryas Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Geology Impact factor: 1.952, year: 2016

  5. Radiocarbon dating and Dendrochronology for Statigraphic Units near Tebano, Senio Northern Apennines - Time frame of Climatic Fluctuation at the onset of the Younger Dryas

    Science.gov (United States)

    Eggenschwiler, Loren; Hajdas, Irka; Cherubini, Paolo; Picotti, Vincenzo; Saurer, Matthias

    2017-04-01

    The presence of Pinus [sylvestris] provides an insight into dramatic events due to climatic changes. Several major and minor climatic fluctuations have had a strong impact on terrestrial and marine environments since the last glacial period to present day (Ravazzi et al. 2006). This study aims to describe the response of a fluvial environment through the use of dendrochronology and stratigraphy. Here, we intend to get a better understanding of how these climatic fluctuations affect the behavior of the Senio River (Lotter et al. 1992). In Tebano, Italy, several Pinus sylvestris subfossil trunks were discovered during excavation for an irrigation pool. Subfossil samples were collected to analyze the climate during the Younger Dryas (11,000 years BP) in detail. Charcoal samples from the Bubano clay quarry extend our research to further to 35,500 cal. years BP. The combination of dendrochronology along with stratigraphy allowed us to examine the climate at a detailed local and apply it to a broader spectrum. Tree-ring measurements and cross dating provided a better understanding and verification of extreme events that occurred during the lifespans of the trees. The use of stable isotopes indicates the extreme conditions that occurred. Radiocarbon dating validates the age of the samples and what geological period they come from. Along with stratigraphy, we were able to compile depth data to create a sediment curve. Using various methods throughout this study, we discovered the climatic situation of Pinus 11,000 years BP and are able to compare them with samples from today. These present day samples mark two of the southernmost extents of the Pinus population. We were then able to comprehend the magnitude of sediment supply and precipitation. Through this collection of methods and data, we are able to understand the influence of climate change in the past and the potential changes of the future. REFERENCES Lotter, A. F.; Eicher, U.; Siegenthaler, U.; Birks, H. J. B

  6. Cough & Cold Medicine Abuse

    Science.gov (United States)

    ... Videos for Educators Search English Español Cough & Cold Medicine Abuse KidsHealth / For Teens / Cough & Cold Medicine Abuse ... resfriado Why Do People Use Cough and Cold Medicines to Get High? There's an ingredient in many ...

  7. Cold fusion

    International Nuclear Information System (INIS)

    Bush, R.T.

    1991-01-01

    The transmission resonance model (TRM) is combined with some electrochemistry of the cathode surface and found to provide a good fit to new data on excess heat. For the first time, a model for cold fusion not only fits calorimetric data but also predicts optimal trigger points. This suggests that the model is meaningful and that the excess heat phenomenon claimed by Fleischmann and Pons is genuine. A crucial role is suggested for the overpotential and, in particular, for the concentration overpotential, i.e., the hydrogen overvoltage. Self-similar geometry, or scale invariance, i.e., a fractal nature, is revealed by the relative excess power function. Heat bursts are predicted with a scale invariance in time, suggesting a possible link between the TRM and chaos theory. The model describes a near-surface phenomenon with an estimated excess power yield of ∼1 kW/cm 3 Pd, as compared to 50 W/cm 3 of reactor core for a good fission reactor. Transmission resonance-induced nuclear transmutation, a new type of nuclear reaction, is strongly suggested with two types emphasized: transmission resonance-induced neutron transfer reactions yielding essentially the same end result as Teller's hypothesized catalytic neutron transfer and a three-body reaction promoted by standing de Broglie waves. In this paper suggestions for the anomalous production of heat, particles, and radiation are given

  8. Cold thermal injury from cold caps used for the prevention of chemotherapy-induced alopecia.

    Science.gov (United States)

    Belum, Viswanath Reddy; de Barros Silva, Giselle; Laloni, Mariana Tosello; Ciccolini, Kathryn; Goldfarb, Shari B; Norton, Larry; Sklarin, Nancy T; Lacouture, Mario E

    2016-06-01

    The use of scalp cooling for the prevention of chemotherapy-induced alopecia (CIA) is increasing. Cold caps are placed onto the hair-bearing areas of the scalp for varying time periods before, during, and after cytotoxic chemotherapy. Although not yet reported, improper application procedures could result in adverse events (AEs). At present, there are no evidence-based scalp cooling protocols, and there is no regulatory oversight of their use. To report the occurrence of cold thermal injury (frostbite) on the scalp, following the use of cold caps for the prevention of CIA. We identified four patients who developed cold thermal injuries on the scalp following the application of cold caps. Medical records were analyzed to retrieve the demographic and clinical characteristics. The cold thermal injuries in our patients were grade 1/2 in severity and improved with topical interventions and interruption of cold cap use, although grade 1 persistent alopecia ensued in 3 patients. The true incidence of such injuries in this setting, however, remains unknown. Cold thermal injuries are likely infrequent and preventable AEs that may result from improper device application procedures during cold cap use. Although these untoward events are usually mild to moderate in severity, the potential occurrence of long-term sequelae (e.g., permanent alopecia and scarring) or the need to discontinue cold cap use, are not known. Prospective studies are needed to further elucidate the risk and standardize healthcare delivery methods, and to improve patient/supportive/healthcare provider education.

  9. Abrupt sea surface pH change at the end of the Younger Dryas in the central sub-equatorial Pacific inferred from boron isotope abundance in corals (Porites

    Directory of Open Access Journals (Sweden)

    A. Juillet-Leclerc

    2010-08-01

    Full Text Available The "δ11B-pH" technique was applied to modern and ancient corals Porites from the sub-equatorial Pacific areas (Tahiti and Marquesas spanning a time interval from 0 to 20.720 calendar years to determine the amplitude of pH changes between the Last Glacial Period and the Holocene. Boron isotopes were measured by Multi-Collector – Inductively Coupled Plasma Mass Spectrometry (MC-ICPMS with an external reproducibility of 0.25‰, allowing a precision of about ±0.03 pH-units for pH values between 8 and 8.3. The boron concentration [B] and isotopic composition of modern samples indicate that the temperature strongly controls the partition coefficient KD for different aragonite species. Modern coral δ11B values and the reconstructed sea surface pH values for different Pacific areas match the measured pH expressed on the seawater scale and confirm the calculation parameters that were previously determined by laboratory calibration exercises. Most ancient sea surface pH reconstructions near Marquesas are higher than modern values. These values range between 8.19 and 8.27 for the Holocene and reached 8.30 at the end of the last glacial period (20.7 kyr BP. At the end of the Younger Dryas (11.50±0.1 kyr BP, the central sub-equatorial Pacific experienced a dramatic drop of up to 0.2 pH-units from the average pH of 8.2 before and after this short event. Using the marine carbonate algorithms, we recalculated the aqueous pCO2 to be 440±25 ppmV at around 11.5 kyr BP for corals at Marquesas and ~500 ppmV near Tahiti where it was assumed that pCO2 in the atmosphere was 250 ppmV. Throughout the Holocene, the difference in pCO2 between the ocean and the atmosphere at Marquesas (ΔpCO2 indicates that the surface waters behave as a moderate CO2 sink or source (−53 to 20 ppmV during El Niño-like conditions. By contrast, during the last glacial/interglacial transition, this area was a marked source of CO2 (21 to 92 ppmV for the atmosphere, highlighting

  10. Inferring the provenance of an alien species with DNA barcodes: the neotropical butterfly Dryas iulia in Thailand.

    Directory of Open Access Journals (Sweden)

    Noah A Burg

    Full Text Available The Neotropical butterfly Dryas iulia has been collected from several locations in Thailand and Malaysia since 2007, and has been observed breeding in the wild, using introduced Passiflora foetida as a larval host plant. The butterfly is bred by a butterfly house in Phuket, Thailand, for release at weddings and Buddhist ceremonies, and we hypothesized that this butterfly house was the source of wild, Thai individuals. We compared wing patterns and COI barcodes from two, wild Thai populations with individuals obtained from this butterfly house. All Thai individuals resemble the subspecies D. iulia modesta, and barcodes from wild and captive Thai specimens were identical. This unique, Thai barcode was not found in any of the 30 specimens sampled from the wild in the species' native range, but is most similar to specimens from Costa Rica, where many exporting butterfly farms are located. These data implicate the butterfly house as the source of Thailand's wild D. iulia populations, which are currently so widespread that eradication efforts are unlikely to be successful.

  11. Inferring the provenance of an alien species with DNA barcodes: the neotropical butterfly Dryas iulia in Thailand.

    Science.gov (United States)

    Burg, Noah A; Pradhan, Ashman; Gonzalez, Rebecca M; Morban, Emely Z; Zhen, Erica W; Sakchoowong, Watana; Lohman, David J

    2014-01-01

    The Neotropical butterfly Dryas iulia has been collected from several locations in Thailand and Malaysia since 2007, and has been observed breeding in the wild, using introduced Passiflora foetida as a larval host plant. The butterfly is bred by a butterfly house in Phuket, Thailand, for release at weddings and Buddhist ceremonies, and we hypothesized that this butterfly house was the source of wild, Thai individuals. We compared wing patterns and COI barcodes from two, wild Thai populations with individuals obtained from this butterfly house. All Thai individuals resemble the subspecies D. iulia modesta, and barcodes from wild and captive Thai specimens were identical. This unique, Thai barcode was not found in any of the 30 specimens sampled from the wild in the species' native range, but is most similar to specimens from Costa Rica, where many exporting butterfly farms are located. These data implicate the butterfly house as the source of Thailand's wild D. iulia populations, which are currently so widespread that eradication efforts are unlikely to be successful.

  12. The impact of climate and environmental processes on vegetation pattern in the Czechowskie lake catchment Czechowo Region (Northern Tuchola Pinewoods) during the Younger Dryas cooling

    Science.gov (United States)

    Noryśkiewicz, Agnieszka Maria; Kramkowski, Mateusz; Słowiński, Michał; Zawiska, Izabela; Lutyńska, Monika; Błaszkiewicz, Mirosław; Brauer, Achim

    2014-05-01

    Czechowskie lake is located in the northern part of the Tuchola Pinewoods District (Northern Poland) in a young glacial landscape. At present, the majority of the area is forested or used for agricultural purposes, but among them a high amount of basins filled with biogenic sediments are present. This area is very suitable for the postglacial vegetation development investigation because of the LST ash and laminated sediments which we found in the Trzechowskie palaeolake and Czechowskie Lake (Wulf et. all 2013). The aim of the research was to reconstruct the past landscape and vegetation response to Younger Dryas cooling and we present the results of the palinological analysis done for 6 core of biogenic sediments. Our main objective was to determine whether local factors such as topography and soil cover have a significant impact on the vegetation, eutrophy and sedimentation rate at this time. In the lake Czechowskie lake catchment we have six cores that cover postglacial succession (Lake Czechowskie small basin - profile JC-12-s; Lake Czechowskiego terrace - profile TK; Lake Czechowskie vicinity - profile "Oko and Cz/80; Trzechowskie paleolake - profile T/trz; Valley between paleolake Trzechowskie and Lake Czechowskie - profile DTCZ-4). The paleoecological research carried out involved an analysis of pollen, macrofossils, Cladocera, diatom, loss-on-ignition and CaCO3 content. The results show, that the dominant plant communities during the Youngers Dryas in the region nearby Lake Czechowskie are heliophytes xeric herb vegetation with juniper (Juniperus communis) shrubs and birch (Betula) and pine (Pinus sylvestris). In the pollen diagrams there was the difference noted in the participation of the dominant pollen, the juniper pollen was always high but varied from 18 to 37%, birch average pollen share was between 17-27%. The thickness and type of the sediment accumulated in Younger Dryas in the presented profiles differs significantly. In the profiles which

  13. Root tensile strength assessment of Dryas octopetala L. and implications for its engineering mechanism on lateral moraine slopes (Turtmann Valley, Switzerland)

    Science.gov (United States)

    Eibisch, Katharina; Eichel, Jana; Dikau, Richard

    2015-04-01

    Geomorphic processes and properties are influenced by vegetation. It has been shown that vegetation cover intercepts precipitation, enhances surface detention and storage, traps sediment and provides additional surface roughness. Plant roots impact the soil in a mechanical and hydrological manner and affect shear strength, infiltration capacity and moisture content. Simultaneously, geomorphic processes disturb the vegetation development. This strong coupling of the geomorphic and ecologic system is investigated in Biogeomorphology. Lateral moraine slopes are characterized by a variety of geomorphic processes, e. g. sheet wash, solifluction and linear erosion. However, some plant species, termed engineer species, possess specific functional traits which allow them to grow under these conditions and also enable them to influence the frequency, magnitude and even nature of geomorphic processes. For lateral moraine slopes, Dryas octopetala L., an alpine dwarf shrub, was identified as a potential engineer species. The engineering mechanism of D. octopetala, based on its morphological (e.g., growth form) and biomechanical (e.g., root strength) traits, yet remains unclear and only little research has been conducted on alpine plant species. The objectives of this study are to fill this gap by (A) quantifying D. octopetala root tensile strength as an important trait considering anchorage in and stabilization of the slope and (B) linking plant traits to the geomorphic process they influence on lateral moraine slopes. D. octopetala traits were studied on a lateral moraine slope in Turtmann glacier forefield, Switzerland. (A) Root strength of single root threads of Dryas octopetala L. were tested using the spring scale method (Schmidt et al., 2001; Hales et al., 2013). Measurement equipment was modified to enable field measurements of roots shortly after excavation. Tensile strength of individual root threads was calculated and statistically analyzed. First results show that

  14. Grooved cold moderator tests

    International Nuclear Information System (INIS)

    Inoue, K.; Kiyanagi, Y.; Iwasa, H.; Watanabe, N.; Ikeda, S.; Carpenter, J.M.; Ishikawa, Y.

    1983-01-01

    We performed some grooved cold moderator experiments for methane at 20 K by using the Hokkaido University linac to obtain information to be used in the planning of the KENS-I' project. Cold neutron gains, spatial distribution of emitted beams and time distribution of the neutrons in the grooved cold moderator were measured. Furthermore, we assessed the effects of the grooved cold moderator on the performances of the spectrometers presently installed at the KENS-I cold source. We concluded that the grooved cold moderator benefited appreciably the performances of the spectrometers

  15. Conceptualizing Cold Disasters

    DEFF Research Database (Denmark)

    Lauta, Kristian Cedervall; Dahlberg, Rasmus; Vendelø, Morten Thanning

    2017-01-01

    In the present article, we explore in more depth the particular circumstances and characteristics of governing what we call ‘cold disasters’, and thereby, the paper sets out to investigate how disasters in cold contexts distinguish themselves from other disasters, and what the implications hereof...... are for the conceptualization and governance of cold disasters. Hence, the paper can also be viewed as a response to Alexander’s (2012a) recent call for new theory in the field of disaster risk reduction. The article is structured in four overall parts. The first part, Cold Context, provides an overview of the specific...... conditions in a cold context, exemplified by the Arctic, and zooms in on Greenland to provide more specific background for the paper. The second part, Disasters in Cold Contexts, discusses “cold disasters” in relation to disaster theory, in order to, elucidate how cold disasters challenge existing...

  16. Working in the Cold

    Centers for Disease Control (CDC) Podcasts

    During the winter, many workers are outdoors, working in cold, wet, icy, or snowy conditions. Learn how to identify symptoms that tell you there may be a problem and protect yourself from cold stress.

  17. Colds and the Flu

    Science.gov (United States)

    ... disease (COPD). What medicines can I give my child? There is no cure for the cold or the flu, and antibiotics do not work against the viruses that cause colds and the flu. Pain relievers such as ...

  18. Cold knife cone biopsy

    Science.gov (United States)

    ... biopsy; Pap smear - cone biopsy; HPV - cone biopsy; Human papilloma virus - cone biopsy; Cervix - cone biopsy; Colposcopy - cone biopsy Images Female reproductive anatomy Cold cone biopsy Cold cone removal References Baggish ...

  19. Cold medicines and children

    Science.gov (United States)

    ... ingredient. Avoid giving more than one OTC cold medicine to your child. It may cause an overdose with severe side ... the dosage instructions strictly while giving an OTC medicine to your child. When giving OTC cold medicines to your child: ...

  20. Glaciation style and the geomorphological record: evidence for Younger Dryas glaciers in the eastern Lake District, northwest England

    Science.gov (United States)

    McDougall, Derek

    2013-08-01

    The Younger Dryas (c. 12,900-11,700 years ago) in Britain witnessed renewed glaciation, with the readvance of ice masses that had survived the preceding Lateglacial Interstadial as well as the formation of new glaciers. The extents of these former glaciers have been mapped by many workers over the past fifty years, usually as a basis for palaeoclimatic investigations. It has frequently been asserted that the landform record is sufficiently clear to allow accurate ice mass reconstructions at or near maximum extents. Detailed geomorphological mapping in the eastern Lake District in NW England, however, demonstrates that this confidence may not always be warranted. Whereas previous workers have interpreted the well-developed moraines that exist in some locations as evidence for an alpine-style of glaciation, with ice restricted to a small number of valleys, this study shows that the most recent glaciation to affect the area was characterised by: (i) extensive summit icefields, which supplied ice to the surrounding valleys; and (ii) a much greater volume of ice in the valleys than previously thought. The discovery that summit icefields were relatively common at this time is consistent with recent studies elsewhere in the Lake District and beyond. More significant, however, is the recognition that changing glacier-topographic interactions over both space and time appears to have had a profound impact on valley-floor glacial landform development, with the absence of clear moraines not necessarily indicating ice-free conditions at this time. This complicates glacier reconstructions based solely on the geomorphological record. Similar geomorphological complexity may be present in other areas that previously supported summit icefields, and this needs to be taken into account in glacier reconstructions.

  1. How cold is cold dark matter?

    International Nuclear Information System (INIS)

    Armendariz-Picon, Cristian; Neelakanta, Jayanth T.

    2014-01-01

    If cold dark matter consists of particles, these must be non-interacting and non-relativistic by definition. In most cold dark matter models however, dark matter particles inherit a non-vanishing velocity dispersion from interactions in the early universe, a velocity that redshifts with cosmic expansion but certainly remains non-zero. In this article, we place model-independent constraints on the dark matter temperature to mass ratio, whose square root determines the dark matter velocity dispersion. We only assume that dark matter particles decoupled kinetically while non-relativistic, when galactic scales had not entered the horizon yet, and that their momentum distribution has been Maxwellian since that time. Under these assumptions, using cosmic microwave background and matter power spectrum observations, we place upper limits on the temperature to mass ratio of cold dark matter today (away from collapsed structures). These limits imply that the present cold dark matter velocity dispersion has to be smaller than 54 m/s. Cold dark matter has to be quite cold, indeed

  2. Observations of cold antihydrogen

    CERN Document Server

    Tan, J N; Gabrielse, G; Oxley, P; Speck, A; Storry, C H; Wessels, M; Grzonka, D; Oelert, W; Schepers, G; Sefzick, T; Walz, J; Pittner, H; Hänsch, T W; Hessels, E A

    2004-01-01

    ATRAP's e/sup +/ cooling of p in a nested Penning trap has led to reports of cold H produced during such cooling by the ATHENA and ATRAP collaborations. To observe H, ATHENA uses coincident annihilation detection and ATRAP uses field ionization followed by p storage. Advantages of ATRAP's field ionization method include the complete absence of any background events, and the first way to measure which H states are produced. ATRAP enhances the H production rate by driving many cycles of e/sup +/ cooling in the nested trap, with more H counted in an hour than the sum of all the other antimatter atoms ever reported. The number of H counted per incident high energy p is also higher than ever observed. The first measured distribution of H states is made using a pre-ionizing electric field between separated production and detection regions. The high rate and the high Rydberg states suggest that the H is formed via three-body recombination, as expected. (22 refs).

  3. Observations of cold antihydrogen

    International Nuclear Information System (INIS)

    Tan, J.N.; Bowden, N.S.; Gabrielse, G.; Oxley, P.; Speck, A.; Storry, C.H.; Wessels, M.; Grzonka, D.; Oelert, W.; Schepers, G.; Sefzick, T.; Walz, J.; Pittner, H.; Haensch, T.W.; Hessels, E.A.

    2004-01-01

    ATRAP's e + cooling of p-bar in a nested Penning trap has led to reports of cold H-bar produced during such cooling by the ATHENA and ATRAP collaborations. To observe H-bar, ATHENA uses coincident annihilation detection and ATRAP uses field ionization followed by p-bar storage. Advantages of ATRAP's field ionization method include the complete absence of any background events, and the first way to measure which H-bar states are produced. ATRAP enhances the H-bar production rate by driving many cycles of e + cooling in the nested trap, with more H-bar counted in an hour than the sum of all the other antimatter atoms ever reported. The number of H-bar counted per incident high energy p-bar is also higher than ever observed. The first measured distribution of H-bar states is made using a pre-ionizing electric field between separated production and detection regions. The high rate and the high Rydberg states suggest that the H-bar is formed via three-body recombination, as expected

  4. Cold formability of steels

    International Nuclear Information System (INIS)

    Lafond, G.; Leclerq, G.; Moliexe, F.; Namdar, R.; Roesch, L.; Sanz, G.

    1977-01-01

    This work was essentially aimed to the study of the following three questions. Is it possible to assess the cold formability of steels using simple material properties as criteria. What values of mechanical properties can one expect to reach in cold formed parts. Are there simple ways of characterizing the speroidization treatments carried out on steels before cold forming operations. The present report describes the results obtained during this investigation. It is logically divided into three separate parts. Experimental study of cold formability in wire drawing. Influence of metallurgical variables on mechanical properties of high carbon cold drawn wires. Contribution to the study of characterization methods of cold forming steels subjected to a spheroidization heat treatment

  5. Cold fusion, Alchemist's dream

    International Nuclear Information System (INIS)

    Clayton, E.D.

    1989-09-01

    In this report the following topics relating to cold fusion are discussed: muon catalysed cold fusion; piezonuclear fusion; sundry explanations pertaining to cold fusion; cosmic ray muon catalysed cold fusion; vibrational mechanisms in excited states of D 2 molecules; barrier penetration probabilities within the hydrogenated metal lattice/piezonuclear fusion; branching ratios of D 2 fusion at low energies; fusion of deuterons into 4 He; secondary D+T fusion within the hydrogenated metal lattice; 3 He to 4 He ratio within the metal lattice; shock induced fusion; and anomalously high isotopic ratios of 3 He/ 4 He

  6. Cold period in the Northern Europe in the past (about 8200 years ago: analysis of empirical data and possible causes

    Directory of Open Access Journals (Sweden)

    I. I. Borzenkova

    2017-01-01

    Full Text Available Cold episode in Northern Europe happened about 8200 years ago was known for a relatively long time, mainly due to paleobotanical (palynological data obtained from analysis of lake and peat sediments. Detailed analysis of ice cores from the Greenland holes GRIP, GISP2, and NGRIP with a time resolution of about 10 years made possible to refine the duration and characteristics of the time structure of this cold period. This cooling lasted for approximately 160 yr. Spore-pollen analysis of lake sediments in Northern Europe (Sweden, Finland, Denmark, Germany, the North and North-West of Russia and deep-sea cores of the North Atlantic showed that the mean annual air temperature during the maximum stage of the cooling was reduced by 1–2 °C, and in some areas by more than 3 °C. The cold spread from the coast of the North Atlantic into the European continent and manifested itself mostly in Sweden, Finland, the Baltic States, and to a lesser extent in the North-West and West of the Russian Federation. In the central Russia and North of 70°N the cooling was weak or absent. The question about a nature of this cold event and other cold spells in Late Glaciation, known as the cold of the early, middle and late Dryas, is widely discussed in the scientific literature. Most of scientists accept a hypothesis proposed more than 20 years ago, that the reduction of air temperatures in regions immediately adjacent to the North Atlantic was caused by the large volume of melt water discharged into the ocean as a result of disintegration and melting of ice-sheets. Climate models that take into account these effects allow estimating a decrease in the air and sea surface temperature due to freshening (desalination of the upper ocean layer, and this confirms that the greatest decrease in temperature should be observed in the regions directly adjacent to the ocean. The increase in global temperature over the last 30 years is estimated to be 0.8 ± 0.2

  7. Cold Antimatter Plasmas, and Aspirations for Cold Antihydrogen

    Science.gov (United States)

    2002-06-24

    UNCLASSIFIED Defense Technical Information Center Compilation Part Notice ADP012494 TITLE: Cold Antimatter Plasmas, and Aspirations for Cold...part numbers comprise the compilation report: ADP012489 thru ADP012577 UNCLASSIFIED Cold Antimatter Plasmas, and Aspirations for Cold Antihydrogen G...and positrons. The antiprotons come initially from the new Antiproton Decel- erator facility at CERN. Good control of such cold antimatter plasmas is

  8. Relative expression of genes related with cold tolerance in ...

    African Journals Online (AJOL)

    Low temperature is one of the main abiotic stresses affecting rice yield in Chile. Alterations in phenology and physiology of the crop are observed after a cold event. The objective of this work was to study the relative expression of genes related with cold stress in Chilean cultivars of rice. For this, we analyzed the expression ...

  9. Impact of the Atlantic Warm Pool on precipitation and temperature in Florida during North Atlantic cold spells

    Energy Technology Data Exchange (ETDEWEB)

    Donders, Timme H. [Utrecht University, Laboratory of Palaeobotany and Palynology, Institute of Environmental Biology, Utrecht (Netherlands); TNO Geological Survey of the Netherlands, Utrecht (Netherlands); Boer, Hugo Jan de; Dekker, Stefan C. [Utrecht University, Department of Environmental Sciences, Faculty of Geosciences, P.O. Box 80115, Utrecht (Netherlands); Finsinger, Walter; Wagner-Cremer, Friederike [Utrecht University, Laboratory of Palaeobotany and Palynology, Institute of Environmental Biology, Utrecht (Netherlands); Grimm, Eric C. [Research and Collections Center, Illinois State Museum, Springfield, IL (United States); Reichart, Gert Jan [Utrecht University, Geochemistry, Department of Earth Sciences, Faculty of Geosciences, P.O. Box 80021, Utrecht (Netherlands)

    2011-01-15

    Recurrent phases of increased pine at Lake Tulane, Florida have previously been related to strong stadials terminated by so-called Heinrich events. The climatic significance of these pine phases has been interpreted in different ways. Using a pollen-climate inference model, we quantified the climate changes and consistently found that mean summer precipitation (P{sub JJA}) increased (0.5-0.9 mm/day) and mean November temperature increased (2.0-3.0 C) during pine phases coeval with Heinrich events and the Younger Dryas. Marine sea surface temperature records indicate that potential sources for these moisture and heat anomalies are in the Gulf of Mexico and the western tropical Atlantic. We explain this low latitude warming by an increased Loop Current facilitated by persistence of the Atlantic Warm Pool during summer. This hypothesis is supported by a climate model sensitivity analysis. A positive heat anomaly in the Gulf of Mexico and equatorial Atlantic best approximates the pollen-inferred climate reconstructions from Lake Tulane during the (stadials around) Heinrich events and the Younger Dryas. (orig.)

  10. Accelerator mass spectrometry: An important tool for the geochronology of past climatic events

    International Nuclear Information System (INIS)

    Jull, A.J.T.; Burr, G.S.; Beck, J.W.; Donahue, D.J.

    2002-01-01

    The development of a good chronology is very important to the understanding of past climatic changes and their relationship to other events. The correlation of distinct climatic features requires a precise chronology. More important also is the need to be able to correlate phenomena which are dated independently. For example, several authors have tried to cross-correlate climatic events observed in Greenland ice cores with climatic events identified in other terrestrial and marine records. The improvement in the radiocarbon calibration curve over the last 25,000 yr and the ability to cross-correlate fluctuations in the 14 C curve directly with those in the ice-core records has improved the situation. This extension of the calibration curve uses tree rings to about 11,900 calibrated years and beyond, using corals and varved marine sediments. Other records take us back to the limits of radiocarbon dating, using lake sediments and speleothems. Another important problem in geochronology of past climate change is that events may be manifest differently in different parts of the world. For example, the uniformly 'cold' younger Dryas in northern Europe can be correlated with oscillatory cold and wet behavior in other parts of the world. Chinese loess deposits show an oscillatory pattern during this time period, and the deserts of the American southwest show a drought followed by a period of increased precipitation. Hence, we must identify local and regional variations as well as global events. Many megafuana became extinct close to the end of the late Pleistocene and the exact time of these extinctions, and whether they are cause by climate alone, or by other pressures such as the expansion of humans into previously unoccupied areas. The exact timing of climatic change is also of importance in understanding the expansion of early man in the New World. The exact time of arrival of early man in the western hemisphere is usually thought to be close to the end of the last

  11. Working in the Cold

    Centers for Disease Control (CDC) Podcasts

    2016-02-08

    During the winter, many workers are outdoors, working in cold, wet, icy, or snowy conditions. Learn how to identify symptoms that tell you there may be a problem and protect yourself from cold stress.  Created: 2/8/2016 by National Institute for Occupational Safety and Health (NIOSH).   Date Released: 2/8/2016.

  12. Cold-Weather Sports

    Science.gov (United States)

    ... Videos for Educators Search English Español Cold-Weather Sports KidsHealth / For Teens / Cold-Weather Sports What's in this article? What to Do? Classes ... weather. What better time to be outdoors? Winter sports can help you burn calories, increase your cardiovascular ...

  13. Cold fusion research

    International Nuclear Information System (INIS)

    1989-11-01

    I am pleased to forward to you the Final Report of the Cold Fusion Panel. This report reviews the current status of cold fusion and includes major chapters on Calorimetry and Excess Heat, Fusion Products and Materials Characterization. In addition, the report makes a number of conclusions and recommendations, as requested by the Secretary of Energy

  14. COLD-WORKED HARDWARE

    Directory of Open Access Journals (Sweden)

    N. M. Strizhak

    2007-01-01

    Full Text Available The different types of cold-worked accessory are examined in the article. The necessity of development of such type of accessory in the Republic of Belarus due to requirements of market is shown. High emphasis is placed on the methods of increase of plasticity of cold-worked accessory from usual mill of RUP and CIS countries.

  15. Liquid metal cold trap

    International Nuclear Information System (INIS)

    Hundal, R.

    1976-01-01

    A cold trap assembly for removing impurities from a liquid metal is described. A hole between the incoming impure liquid metal and purified outgoing liquid metal acts as a continuous bleed means and thus prevents the accumulation of cover gases within the cold trap assembly

  16. Assessing cold chain status in a metro city of India: an intervention study.

    Science.gov (United States)

    Mallik, S; Mandal, P K; Chatterjee, C; Ghosh, P; Manna, N; Chakrabarty, D; Bagchi, S N; Dasgupta, S

    2011-03-01

    Cold chain maintenance is an essential activity to maintain the potency of vaccines and to prevent adverse events following immunization. One baseline study highlighted the unsatisfactory cold chain status in city of Kolkata in India. To assess the changes which occurred in the cold chain status after the intervention undertaken to improve the status and also to assess the awareness of the cold chain handlers regarding cold chain maintenance. Intervention consisted of reorganization of cold chain points and training of health manpower in Kolkata Municipal area regarding immunization and cold chain following the guidelines as laid by Govt of India. Reevaluation of cold chain status was done at 20 institutions selected by stratified systematic random sampling after the intervention. The results were compared with baseline survey. Significant improvement had been observed in correct placing of cold chain equipment, maintenance of stock security, orderly placing of ice packs, diluents and vaccines inside the equipment, temperature recording and maintenance. But awareness and skill of cold chain handlers regarding basics of cold chain maintenance was not satisfactory. The success of intervention included significant improvement of cold chain status including creation of a designated cold chain handler. The gaps lay in non-availability of non-electrical cold chain equipment and separate cold chain room, policy makers should stress. Cold chain handlers need reorientation training regarding heat & cold sensitive vaccines, preventive maintenance and correct contingency plan.

  17. Two cold-season derechoes in Europe

    Science.gov (United States)

    Gatzen, Christoph; Púčik, Tomas; Ryva, David

    2011-06-01

    In this study, we apply for the first time the definition of a derecho (Johns and Hirt, 1987) to European cold-season convective storm systems. These occurred on 18 January 2007 and 1 March 2008, respectively, and they are shown to fulfill the criteria of a derecho. Damaging winds were reported over a distance of 1500 km and locally reached F3 intensity. Synoptic analysis for the events reveal strongly forced situations that have been described for cold-season derechoes in the United States. A comparison of swaths of damaging winds, radar structures, detected lightning, cold pool development, and cloud-top temperatures indicates that both derechoes formed along cold fronts that were affected by strong quasi-geostrophic forcing. It seems that the overlap of the cold front position with the strong differential cyclonic vorticity advection at the cyclonic flank of mid-level jet streaks favoured intense convection and high winds. The movement and path width of the two derechoes seemed to be related to this overlap. The wind gust intensity that was also different for both events is discussed and could be related to the component of the mid-level winds perpendicular to the gust fronts.

  18. Behaviour of the lake district ice lobe of the Scandinavian ice sheet during the younger dryas chronozone (ca. 12 800 - 11 500 years ago)

    Energy Technology Data Exchange (ETDEWEB)

    Lunkka, J.P.; Erikkilae, A. [Oulu Univ. (Finland)

    2012-04-15

    It is highly relevant to picture the conditions that prevailed under and in front of the ice sheets as they were stationary or in equilibrium for many hundreds of years. This knowledge is particularly relevant when planning to dispose of spent nuclear fuel in a repository underground. For estimating what kind of conditions might exist at the ice margin basic knowledge is needed from the palaeoice sheets that remained stationary for long periods of time. During Younder Dryas Stadial (c. 12 800 - 11 500 years ago) glaciers remained stationary or advanced worldwide as a result of climate cooling. The major end moraine complexes that run around Fennoscandia, Russian Karelia and the Kola Peninsula were deposited at that time and mark the former Younger Dryas ice margin. It this work the palaeoenvironments have been reconstructed in order to reveal the conditions that existed for more than 1000 years in the area where the former Lake District Ice Lobe of the Scandinavian Ice Sheet was in the Salpausselkae zone in southern Finland. Work was carried out using GIS-based reconstruction tools, sedimentological and geophysical (ground penetrating radar) methods. In addition, a detailed palaeoenvironmental reconstruction was produced for the Kylaeniemi area which forms a part of the Salpausselkae II end moraine. The GIS-based reconstructions clearly indicate that the ice grounding line of the Lake District Ice Lobe was standing in shallow water depth in the Baltic Ice Lake. The water depth in front of Salpausselkae I, which marks the ice margin at c. 12 500 years ago was mainly between 20-40 metres. When the ice margin was in Salpausselkae II at around 11 700 years ago the water depth in front of the ice margin was on average less than 20 metres. Although the surface profile of ice was not possible to calculate subgalcial and ice frontal landforms indicate that subgalcial tunnel systems were responsible for releasing melt water and sediment to the ice margin throughout the

  19. Testing the Younger Dryas impact hypothesis with platinum-group elements (PGE), Re, and Os isotopes in sediments from Hall's Cave and Freidken Archaeological site, Texas

    Science.gov (United States)

    Sun, N.; Brandon, A. D.; Forman, S. L.

    2017-12-01

    The Younger Dryas impact hypothesis suggests that extraterrestrial (ET) object(s) hit and exploded over North America 12,900 years ago and triggered the onset of Younger Dryas (YD) cooling and widespread megafaunal extinctions and the demise of the Clovis archeological culture. Supporting signatures such as concentrated carbon spherules and enlogaes, magnetic grains and spherules, nanodiamonds, and Ir-enrichment have been reported, but over time their lack of reproducibility of results at different locations have brought into question the impact hypothesis. Among the impact signatures investigated by previous studies, only few researchers included Re and platinum group element (PGE: Os, Ir, Ru, Rh, Pt, and Pd) characteristic concentrations, and 187Os/188Os ratios for ET mixing in terrestrial materials. Less than 1% of ET materials can provide enriched PGE concentrations, such that PGE are a sensitive tool to identify ET input in terrestrial materials. Because of the large difference between chondritic and continental crust 187Os/188Os ratios, 0.127 and >1.4, respectively, the 187Os/188Os ratios are also highly sensitive indicators of an extraterrestrial component in terrestrial and marine sediments. In this study, we examine sediments associated with the YD from two reported sites in North America, Hall's Cave and the Freidken Archaeological site in Central Texas, using the PGE and Re geochemical approach to test the evidence of the extraterrestrial projectiles during Younger Dryas period. Our current data show at Hall's Cave the PGE concentrations and patterns do not confirm the presence of an elevated meteoritic contribution. However, the 187Os/188Os depth profile shows a sudden 187Os/188Os decrease from 2.28 2.45 to 1.64 at the YD boundary layer, consistent with an increase in material derived from ET projectiles with chondritic 187Os/188Os ratios contaminating the Earth surface at the time of the YD extinction. Additional samples from the YD boundary at the

  20. Behaviour of the lake district ice lobe of the Scandinavian ice sheet during the younger dryas chronozone (ca. 12 800 - 11 500 years ago)

    International Nuclear Information System (INIS)

    Lunkka, J.P.; Erikkilae, A.

    2012-04-01

    It is highly relevant to picture the conditions that prevailed under and in front of the ice sheets as they were stationary or in equilibrium for many hundreds of years. This knowledge is particularly relevant when planning to dispose of spent nuclear fuel in a repository underground. For estimating what kind of conditions might exist at the ice margin basic knowledge is needed from the palaeoice sheets that remained stationary for long periods of time. During Younder Dryas Stadial (c. 12 800 - 11 500 years ago) glaciers remained stationary or advanced worldwide as a result of climate cooling. The major end moraine complexes that run around Fennoscandia, Russian Karelia and the Kola Peninsula were deposited at that time and mark the former Younger Dryas ice margin. It this work the palaeoenvironments have been reconstructed in order to reveal the conditions that existed for more than 1000 years in the area where the former Lake District Ice Lobe of the Scandinavian Ice Sheet was in the Salpausselkae zone in southern Finland. Work was carried out using GIS-based reconstruction tools, sedimentological and geophysical (ground penetrating radar) methods. In addition, a detailed palaeoenvironmental reconstruction was produced for the Kylaeniemi area which forms a part of the Salpausselkae II end moraine. The GIS-based reconstructions clearly indicate that the ice grounding line of the Lake District Ice Lobe was standing in shallow water depth in the Baltic Ice Lake. The water depth in front of Salpausselkae I, which marks the ice margin at c. 12 500 years ago was mainly between 20-40 metres. When the ice margin was in Salpausselkae II at around 11 700 years ago the water depth in front of the ice margin was on average less than 20 metres. Although the surface profile of ice was not possible to calculate subgalcial and ice frontal landforms indicate that subgalcial tunnel systems were responsible for releasing melt water and sediment to the ice margin throughout the

  1. Human whole body cold adaptation.

    NARCIS (Netherlands)

    Daanen, Hein A.M.; Van Marken Lichtenbelt, Wouter D.

    2016-01-01

    Reviews on whole body human cold adaptation generally do not distinguish between population studies and dedicated acclimation studies, leading to confusing results. Population studies show that indigenous black Africans have reduced shivering thermogenesis in the cold and poor cold induced

  2. Chilling Out With Colds

    Science.gov (United States)

    ... and use the time to read, listen to music, or watch a movie. In other words, chill out and you might prevent a cold! Reviewed by: Patricia ... Policy Permissions Guidelines Privacy Policy & Terms of Use Notice ...

  3. Cold Vacuum Drying Facility

    Data.gov (United States)

    Federal Laboratory Consortium — Located near the K-Basins (see K-Basins link) in Hanford's 100 Area is a facility called the Cold Vacuum Drying Facility (CVDF).Between 2000 and 2004, workers at the...

  4. Dence Cold Matter

    Directory of Open Access Journals (Sweden)

    Stavinskiy Alexey

    2014-04-01

    Full Text Available Possible way to create dense cold baryonic matter in the laboratory is discussed. The density of this matter is comparable or even larger than the density of neutron star core. The properties of this matter can be controlled by trigger conditions. Experimental program for the study of properties of dense cold matter for light and heavy ion collisions at initial energy range √sNN~2-3GeV is proposed..

  5. Hypothermic general cold adaptation induced by local cold acclimation.

    Science.gov (United States)

    Savourey, G; Barnavol, B; Caravel, J P; Feuerstein, C; Bittel, J H

    1996-01-01

    To study relationships between local cold adaptation of the lower limbs and general cold adaptation, eight subjects were submitted both to a cold foot test (CFT, 5 degrees C water immersion, 5 min) and to a whole-body standard cold air test (SCAT, 1 degree C, 2 h, nude at rest) before and after a local cold acclimation (LCA) of the lower limbs effected by repeated cold water immersions. The LCA induced a local cold adaptation confirmed by higher skin temperatures of the lower limbs during CFT and a hypothermic insulative general cold adaptation (decreased rectal temperature and mean skin temperature P adaptation was related to the habituation process confirmed by decreased plasma concentrations of noradrenaline (NA) during LCA (P general cold adaptation was unrelated either to local cold adaptation or to the habituation process, because an increased NA during SCAT after LCA (P syndrome" occurring during LCA.

  6. Interhemispheric correlation of late pleistocene glacial events.

    Science.gov (United States)

    Lowell, T V; Heusser, C J; Andersen, B G; Moreno, P I; Hauser, A; Heusser, L E; Schlüchter, C; Marchant, D R; Denton, G H

    1995-09-15

    A radiocarbon chronology shows that piedmont glacier lobes in the Chilean Andes achieved maxima during the last glaciation at 13,900 to 14,890, 21,000, 23,060, 26,940, 29,600, and >/=33,500 carbon-14 years before present ((14)C yr B.P.) in a cold and wet Subantarctic Parkland environment. The last glaciation ended with massive collapse of ice lobes close to 14,000(14)C yr B.P., accompanied by an influx of North Patagonian Rain Forest species. In the Southern Alps of New Zealand, additional glacial maxima are registered at 17,720(14)C yr B.P., and at the beginning of the Younger Dryas at 11,050 (14)C yr B. P. These glacial maxima in mid-latitude mountains rimming the South Pacific were coeval with ice-rafting pulses in the North Atlantic Ocean. Furthermore, the last termination began suddenly and simultaneously in both polar hemispheres before the resumption of the modern mode of deep-water production in the Nordic Seas. Such interhemispheric coupling implies a global atmospheric signal rather than regional climatic changes caused by North Atlantic thermohaline switches or Laurentide ice surges.

  7. Cold moderators at ORNL

    International Nuclear Information System (INIS)

    Lucas, A. T.

    1997-09-01

    The Advanced Neutron Source (ANS) cold moderators were not an 'Oak Ridge first', but would have been the largest both physically and in terms of cold neutron flux. Two cold moderators were planned each 410 mm in diameter and containing about 30L of liquid deuterium. They were to be completely independent of each other. A modular system design was used to provide greater reliability and serviceability. When the ANS was terminated, upgrading of the resident High Flux Isotope Reactor (HFIR) was examined and an initial study was made into the feasibility of adding a cold source. Because the ANS design was modular, it was possible to use many identical design features. Sub-cooled liquid at 4 bar abs was initially chosen for the HFIR design concept, but this was subsequently changed to 15 bar abs to operate above the critical pressure. As in the ANS, the hydrogen will operate at a constant pressure throughout the temperature range and a completely closed loop with secondary containment was adopted. The heat load of 2 kW made the heat flux comparable with that of the ANS. Subsequent studies into the construction of cryogenic moderators for the proposed new Synchrotron Neutron source indicated that again many of the same design concepts could be used. By connecting the two cold sources together in series, the total heat load of 2 kW is very close to that of the HFIR allowing a very similar supercritical hydrogen system to be configured. The two hydrogen moderators of the SNS provide a comparable heat load to the HFIR moderator. It is subsequently planned to connect the two in series and operate from a single cold loop system, once again using supercritical hydrogen. The spallation source also provided an opportunity to re-examine a cold pellet solid methane moderator operating at 20K.

  8. Forecasting Turbine Icing Events

    DEFF Research Database (Denmark)

    Davis, Neil; Hahmann, Andrea N.; Clausen, Niels-Erik

    2012-01-01

    In this study, we present a method for forecasting icing events. The method is validated at two European wind farms in with known icing events. The icing model used was developed using current ice accretion methods, and newly developed ablation algorithms. The model is driven by inputs from the WRF...... mesoscale model, allowing for both climatological estimates of icing and short term icing forecasts. The current model was able to detect periods of icing reasonably well at the warmer site. However at the cold climate site, the model was not able to remove ice quickly enough leading to large ice...

  9. Warming up to cold fusion

    International Nuclear Information System (INIS)

    Storms, E.

    1994-01-01

    The idea that tabletop equipment at room temperature could produce nuclear fusion was widely rejected five years ago by the scientific community. Nevertheless, recent results from numerous labs show that a novel phenomena of some kind may indeed be occurring, though theorist are still groping for an explanation. Many aspects of the cold fusion effect are now reproducible if known procedures are used. Palladium, when reacted with enough deuterium, apparently converts to a special condition of matter in which various nuclear reactions--including deuterium-deuterium fusion--can occur despite the repulsive force of the two positive charged nuclei. These reactions can be made to proceed rapidly enough to produce measurable heat. Scientist have published several dozen models, ranging from highly analytical approaches to pictorial representations, to explain these events. Most theories address only the problem of overcoming the coulombic barrier--how it is possible for nuclei to overcome their natural repulsion for each other without an infusion of massive amounts of energy from the outside. None of the proposed explanations accounts for the full range of experimental observations. Nevertheless a workable theory is crucial if we ever hope to apply cold fusion

  10. Hydrothermal Cold Sintering

    Science.gov (United States)

    Kang, Xiaoyu

    C, respectively. Process variables were defined and effects of individual parameters were studied systematically through control variable method with Li2MoO4-water system. Crystalline structure, fractured surface morphology and chemical bonding information of the cold sintered pellets were studied with X-ray diffraction (XRD), field effect scanning electron microscopy (FE-SEM) and Raman spectroscopy, etc. Densification mechanism studies were conducted on ZnO. Through comparison experiments, it was found that the Zn2+ concentration in the solution is critical for densification, while dissolution of grains only serves as a means to the former. Through pressure dependent studies, a critical value was found, which correlated well with the hydrostatic pressure keeping liquid water from thermal expansion. These results confirmed establishment of hydrothermal condition that would be important for mass transport in densification. Densification rate variations with process time was estimated and similar time dependence to Kingery's model was found. The densification process was proposed to be consist of three consecutive stages, which are quick initial compaction, grain rearrangement and dissolution-reprecipitation events. Binary metal oxides with different acidities were subjected to cold sintering with various aqueous solutions in establishing a criteria for material selection. It was found that in general materials with high solubility at around neutral pH, high dissolution kinetics and similar free energy to their hydroxides or hydrates at ambient would be more likely for full densification with high phase purity. The anions in solution should also be wisely selected to avoid stable compound or complex formation. To extend the applicable material list for full densification, non-aqueous solvent of dimethyl sulfoxide (DMSO) based solution was studied for cold sintering. Both improvement of pellet density and suppression of hydroxide formation were achieved for MnO by using DMSO

  11. Cold water injection nozzles

    International Nuclear Information System (INIS)

    Kura, Masaaki; Maeda, Masamitsu; Endo, Takio.

    1979-01-01

    Purpose: To inject cold water in a reactor without applying heat cycles to a reactor container and to the inner wall of a feedwater nozzle by securing a perforated plate at the outlet of the cold water injection nozzle. Constitution: A disc-like cap is secured to the final end of a return nozzle of a control rod drive. The cap prevents the flow of a high temperature water flowing downward in the reactor from entering into the nozzle. The cap is perforated with a plurality of bore holes for injecting cold water into the reactor. The cap is made to about 100 mm in thickness so that the cold water passing through the bore holes is heated by the heat conduction in the cap. Accordingly, the flow of high temperature water flowing downwardly in the reactor is inhibited by the cap from backward flowing into the nozzle. Moreover, the flow of the cold water in the nozzle is controlled and rectified when passed through the bore holes in the cap and then injected into the reactor. (Yoshino, Y.)

  12. Rethinking Little Rock: The Cold War Politics of School Integration in the United States

    Science.gov (United States)

    Dejong-Lambert, William

    2007-01-01

    Though the impact of the cold war on the civil rights movement continued long after the desegregation crisis in Little Rock, the timing of the events in Arkansas, particularly the events at Central High School, constituted a unique moment in the history of the cold war. Up until the fall of 1957, the Soviet Union had been perceived as less…

  13. Cold regions isotope applications

    International Nuclear Information System (INIS)

    Perrigo, L.D.; Divine, T.E.

    1976-04-01

    Pacific Northwest Laboratories (PNL) started the Cold Regions Isotope Applications Program in FY-1975 to identify special conditions in the Arctic and similar geographic areas (Cold Regions) where radioisotope power, heater, or sterilization systems would be desirable and economically viable. Significant progress was made in the first year of this program and all objectives for this initial 12-month period were achieved. The major conclusions and recommendations resulting for this effort are described below. The areas of interest covered include: radiosterilization of sewage; heating of septic tanks; and radioisotope thermoelectric generators as power sources for meteorological instruments and navigational aids

  14. Commemoration of a cold war

    DEFF Research Database (Denmark)

    Farbøl, Rosanna

    2015-01-01

    This article brings together the fields of Cold War studies and memory studies. In Denmark, a remarkable institutionalisation of Cold War memory has taken place in the midst of a heated ideological battle over the past and whether to remember the Cold War as a ‘war’. Using Danish Cold War museums...... and heritage sites as case studies, this article sheds new light on the politics of history involved in Cold War commemoration. It suggests that the Cold War is commemorated as a war, yet this war memory is of a particular kind: it is a war memory without victims....

  15. Tracking the evolution of a cold stress associated gene family in cold tolerant grasses

    DEFF Research Database (Denmark)

    Sandve, Simen R; Rudi, Heidi; Asp, Torben

    2008-01-01

    to the repeat motifs of the IRI-domain in cold tolerant grasses. Finally we show that the LRR-domain of carrot and grass IRI proteins both share homology to an Arabidopsis thaliana LRR-trans membrane protein kinase (LRR-TPK). Conclusion The diverse IRI-like genes identified in this study tell a tale...... of a complex evolutionary history including birth of an ice binding domain, a burst of gene duplication events after cold tolerant grasses radiated from rice, protein domain structure differentiation between paralogs, and sub- and/or neofunctionalisation of IRI-like proteins. From our sequence analysis we...

  16. Cold spray nozzle design

    Science.gov (United States)

    Haynes, Jeffrey D [Stuart, FL; Sanders, Stuart A [Palm Beach Gardens, FL

    2009-06-09

    A nozzle for use in a cold spray technique is described. The nozzle has a passageway for spraying a powder material, the passageway having a converging section and a diverging section, and at least the diverging section being formed from polybenzimidazole. In one embodiment of the nozzle, the converging section is also formed from polybenzimidazole.

  17. Cold fusion - todays situation

    International Nuclear Information System (INIS)

    Malmqvist, K.

    1993-01-01

    A brief review of the history of cold fusion is given. It is noted that it is not possible to draw any definite conclusions about all the experimental and theoretical details, but that some of the results presented do not seem to be reached according to the normal scientific methods. 6 figs

  18. Recent Cold War Studies

    Science.gov (United States)

    Pineo, Ronn

    2003-01-01

    Cold War historiography has undergone major changes since the 1991 collapse of the Soviet Union. For two years (1992-1993) the principal Soviet archives fell open to scholars, and although some of the richest holdings are now once again closed, new information continues to find its way out. Moreover, critical documentary information has become…

  19. Expert Cold Structure Development

    Science.gov (United States)

    Atkins, T.; Demuysere, P.

    2011-05-01

    The EXPERT Program is funded by ESA. The objective of the EXPERT mission is to perform a sub-orbital flight during which measurements of critical aero- thermodynamic phenomena will be obtained by using state-of-the-art instrumentation. As part of the EXPERT Flight Segment, the responsibility of the Cold Structure Development Design, Manufacturing and Validation was committed to the Belgian industrial team SONACA/SABCA. The EXPERT Cold Structure includes the Launcher Adapter, the Bottom Panel, the Upper Panel, two Cross Panels and the Parachute Bay. An additional Launcher Adapter was manufactured for the separation tests. The selected assembly definition and manufacturing technologies ( machined parts and sandwich panels) were dictated classically by the mass and stiffness, but also by the CoG location and the sensitive separation interface. Used as support for the various on-board equipment, the Cold Structure is fixed to but thermally uncoupled from the PM 1000 thermal shield. It is protect on its bottom panel by a thermal blanket. As it is a protoflight, analysis was the main tool for the verification. Low level stiffness and modal analysis tests have also been performed on the Cold Structure equipped with its ballast. It allowed to complete its qualification and to prepare SONACA/SABCA support for the system dynamic tests foreseen in 2011. The structure was finally coated with a thermal control black painting and delivered on time to Thales Alenia Space-Italy end of March 201.

  20. Detection of cold pain, cold allodynia and cold hyperalgesia in freely behaving rats

    Directory of Open Access Journals (Sweden)

    Woolf Clifford J

    2005-12-01

    Full Text Available Abstract Background Pain is elicited by cold, and a major feature of many neuropathic pain states is that normally innocuous cool stimuli begin to produce pain (cold allodynia. To expand our understanding of cold induced pain states we have studied cold pain behaviors over a range of temperatures in several animal models of chronic pain. Results We demonstrate that a Peltier-cooled cold plate with ± 1°C sensitivity enables quantitative measurement of a detection withdrawal response to cold stimuli in unrestrained rats. In naïve rats the threshold for eliciting cold pain behavior is 5°C. The withdrawal threshold for cold allodynia is 15°C in both the spared nerve injury and spinal nerve ligation models of neuropathic pain. Cold hyperalgesia is present in the spared nerve injury model animals, manifesting as a reduced latency of withdrawal response threshold at temperatures that elicit cold pain in naïve rats. We also show that following the peripheral inflammation produced by intraplantar injection of complete Freund's adjuvant, a hypersensitivity to cold occurs. Conclusion The peltier-cooled provides an effective means of assaying cold sensitivity in unrestrained rats. Behavioral testing of cold allodynia, hyperalgesia and pain will greatly facilitate the study of the neurobiological mechanisms involved in cold/cool sensations and enable measurement of the efficacy of pharmacological treatments to reduce these symptoms.

  1. Burning Cold: Involvement of TRPA1 in Noxious Cold Sensation

    OpenAIRE

    Kwan, Kelvin Y.; Corey, David P.

    2009-01-01

    Soon after its discovery ten years ago, the ion channel TRPA1 was proposed as a sensor of noxious cold. Evidence for its activation by painfully cold temperatures (below ~15° C) has been mixed, however. Some groups found that cold elicits a nonselective conductance in cells expressing TRPA1; others found no activation, or argued that activation is an indirect effect of elevated \\(Ca^{ 2+}\\) . Sensory cells from the trigeminal and dorsal root ganglia that are activated by cold were sometimes c...

  2. Seven cases of upper gastrointestinal bleeding after cold biopsy

    OpenAIRE

    Alneaimi, Khaled; Abdelmoula, Ali; Vincent, Magalie; Savale, Camille; Baye, Birane; Lesur, Gilles

    2016-01-01

    Background and study aims: Routine biopsy of the upper gastrointestinal tract is performed with increasing frequency. It is generally considered to be safe without significant complication. However, gastrointestinal bleeding as a result of cold biopsy is a known complication. We report seven cases of upper gastrointestinal bleeding after cold biopsy and discuss clinical data, risks factors, severity and management of this event. We suggest that physicians must be more cautious with this rare ...

  3. Higgsino cold dark matter motivated by collider data

    International Nuclear Information System (INIS)

    Kane, G.L.; Wells, J.D.

    1996-01-01

    Motivated by a supersymmetric interpretation of the CDF eeγγ+E/ T event and the reported Z→ bar bb excess at LEP, we analyze the implied Higgsino-like lightest supersymmetric partner as a cold dark matter candidate. We examine constraints and calculate its relic density, obtaining 0.05 2 <1. Thus it is a viable cold dark matter candidate, and we discuss its favorable prospects for laboratory detection. copyright 1996 The American Physical Society

  4. Flu and Colds: In Depth

    Science.gov (United States)

    ... to prevent colds or relieve cold symptoms. Andrographis (Andrographis paniculata) Chinese herbal medicines Green tea Guided imagery Hydrotherapy ... measurements (VAS) to assess the effectiveness of standardized Andrographis paniculata extract SHA-10 in reducing the symptoms of ...

  5. Herpes Simplex Virus (Cold Sores)

    Science.gov (United States)

    ... Print Share Cold Sores in Children: About the Herpes Simplex Virus Page Content ​A child's toddler and ... Cold sores (also called fever blisters or oral herpes) start as small blisters that form around the ...

  6. Imaging with cold neutrons

    International Nuclear Information System (INIS)

    Lehmann, E.H.; Kaestner, A.; Josic, L.; Hartmann, S.; Mannes, D.

    2011-01-01

    Neutrons for imaging purposes are provided mainly from thermal beam lines at suitable facilities around the world. The access to cold neutrons is presently limited to very few places only. However, many challenging options for imaging with cold neutrons have been found out, given by the interaction behavior of the observed materials with neutrons in the cold energy range (3-10 A). For absorbing materials, the interaction probability increases proportionally with the wavelength with the consequence of more contrast but less transmission with cold neutrons. Many materials are predominantly scattering neutrons, in particular most of crystalline structural materials. In these cases, cold neutrons play an important role by covering the energy range of the most important Bragg edges given by the lattice planes of the crystallites. This particular behavior can be used for at least two important aspects-choosing the right energy of the initial beam enables to have a material more or less transparent, and a direct macroscopic visualization of the crystalline structure and its change in a manufacturing process. Since 2006, PSI operates its second beam line for neutron imaging, where cold neutrons are provided from a liquid deuterium cold source (operated at 25 K). It has been designed to cover the most current aspects in neutron imaging research with the help of high flexibility. This has been done with changeable inlet apertures, a turbine based velocity selector, two beam positions and variable detector systems, satisfying the demands of the individual investigation. The most important detection system was found to be a micro-tomography system that enables studies in the presently best spatial resolution. In this case, the high contrast from the sample interaction process and the high detection probability for the cold neutrons combines in an ideal combination for the best possible performance. Recently, it was found out that the energy selective studies might become a

  7. Human whole body cold adaptation.

    OpenAIRE

    Daanen, Hein A.M.; Van Marken Lichtenbelt, Wouter D.

    2016-01-01

    ABSTRACT Reviews on whole body human cold adaptation generally do not distinguish between population studies and dedicated acclimation studies, leading to confusing results. Population studies show that indigenous black Africans have reduced shivering thermogenesis in the cold and poor cold induced vasodilation in fingers and toes compared to Caucasians and Inuit. About 40,000?y after humans left Africa, natives in cold terrestrial areas seems to have developed not only behavioral adaptations...

  8. Human whole body cold adaptation.

    Science.gov (United States)

    Daanen, Hein A M; Van Marken Lichtenbelt, Wouter D

    2016-01-01

    Reviews on whole body human cold adaptation generally do not distinguish between population studies and dedicated acclimation studies, leading to confusing results. Population studies show that indigenous black Africans have reduced shivering thermogenesis in the cold and poor cold induced vasodilation in fingers and toes compared to Caucasians and Inuit. About 40,000 y after humans left Africa, natives in cold terrestrial areas seems to have developed not only behavioral adaptations, but also physiological adaptations to cold. Dedicated studies show that repeated whole body exposure of individual volunteers, mainly Caucasians, to severe cold results in reduced cold sensation but no major physiological changes. Repeated cold water immersion seems to slightly reduce metabolic heat production, while repeated exposure to milder cold conditions shows some increase in metabolic heat production, in particular non-shivering thermogenesis. In conclusion, human cold adaptation in the form of increased metabolism and insulation seems to have occurred during recent evolution in populations, but cannot be developed during a lifetime in cold conditions as encountered in temperate and arctic regions. Therefore, we mainly depend on our behavioral skills to live in and survive the cold.

  9. Wind energy under cold climate conditions

    Energy Technology Data Exchange (ETDEWEB)

    Maribo Pedersen, B.

    1999-03-01

    There is an increasing interest in wind energy production under different climatic conditions, among them cold climate and icing conditions. More and more wind turbines are being installed in cold climates and even adapted technology has been developed for that environment. Various national activities are going on in at least Finland, Canada, Italy, Sweden, etc. and international collaboration has been carried out within the European Union's Non-nuclear energy programme. Wind turbine operation is affected by both the cold temperatures and the formation of ice on the blades and the supporting structure. Cold temperatures can be handled by material selections known in other technical fields but to prevent icing, new techniques have to be - and have been - developed. Icing affects the reliability of anemometers, which concerns both turbine control and resource estimation, and changes the aerodynamics of the blades, which eventually stops the turbine. In addition, occasional icing events can locally affect public safety. The development of applied technology has entered some different paths and different solutions are tried out. As the applications are entering a commercial phase, these is a request to gather the experiences and monitor the reliability in a form that can be utilised by developers, manufactureres, consultants and other tenderers. The Topical Experts Meeting will focus on site classification, operational experiences, modelling and mesurements of ice induced loads and safety aspects. (EHS)

  10. The need to be cold : cold warriors

    Energy Technology Data Exchange (ETDEWEB)

    Gregoire, L.

    2008-10-15

    This article discussed the changing climate of Ellesmere Island and the adaptation of the Inuit in response to the climate change, with particular reference to Canada's most northern community of Grise Fiord. Because of the changing climate, the vast northern landscape that the Inuit navigated for centuries by reading its subtle signs is becoming warmer, softer, and unpredictable. The geographic history and demographics of Grise Fiord were described. The community's main water supply comes from a glacier which is sinking. The negative impacts of ice shrinkage on this northern community and on the environment were presented. These included more international shipping through the Arctic, more resource exploration, a greater risk of environmental contamination, and reduced habitat for the polar bears and seals that eat, mate, and reproduce on the ice. Climate change impacts on the sea and sea ice were also discussed. Several photographs illustrating the changing climate were presented. The article noted that climate change could destroy the Inuit culture, making climate change an issue of human rights, notably the right to live connected to the land and the right to be cold. It was concluded that in one generation, Inuit were swept up by both a social and an economic upheaval. In one more generation, they will undergo an environmental shift. 13 figs.

  11. WISPy cold dark matter

    Energy Technology Data Exchange (ETDEWEB)

    Arias, Paola [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Pontificia Univ. Catolica de Chile, Santiago (Chile). Facultad de Fisica; Cadamuro, Davide; Redondo, Javier [Max-Planck-Institut fuer Physik, Muenchen (Germany); Goodsell, Mark [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); European Organization for Nuclear Research (CERN), Geneva (Switzerland); Jaeckel, Joerg [Durham Univ. (United Kingdom). Inst. for Particle Physics Phenomenology; Ringwald, Andreas [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2012-01-15

    Very weakly interacting slim particles (WISPs), such as axion-like particles (ALPs) or hidden photons (HPs), may be non-thermally produced via the misalignment mechanism in the early universe and survive as a cold dark matter population until today. We find that, both for ALPs and HPs whose dominant interactions with the standard model arise from couplings to photons, a huge region in the parameter spaces spanned by photon coupling and ALP or HP mass can give rise to the observed cold dark matter. Remarkably, a large region of this parameter space coincides with that predicted in well motivated models of fundamental physics. A wide range of experimental searches - exploiting haloscopes (direct dark matter searches exploiting microwave cavities), helioscopes (searches for solar ALPs or HPs), or light-shining-through-a-wall techniques - can probe large parts of this parameter space in the foreseeable future. (orig.)

  12. Progress with cold antihydrogen

    CERN Document Server

    Charlton, M; Amsler, C; Bonomi, G; Bowe, P D; Canali, C; Carraro, C; Cesar, C L; Doser, M; Fontana, A; Fujiwara, M C; Funakoshi, R; Genova, P; Hangst, J S; Hayano, R S; Johnson, I; Jørgensen, L V; Kellerbauer, A G; Lagomarsino, V; Landua, Rolf; Lodi-Rizzini, E; Macri, M; Madsen, N; Manuzio, G; Mitchard, D; Montagna, P; Pruys, H; Regenfus, C; Rotondi, A; Testera, G; Variola, A; Venturelli, L; Van der Werf, D P; Yamazaki, Y; Zurlo, N

    2006-01-01

    The creation of cold antihydrogen by the ATHENA and ATRAP collaborations, working at CERN's unique Antiproton Decelerator (AD) facility, has ushered in a new era in atomic physics. This contribution will briefly review recent results from the ATHENA experiment. These include discussions of antiproton slowing down in a cold positron gas during antihydrogen formation, information derived on the dependence of the antihydrogen formation rate upon the temperature of the stored positron plasma and, finally, upon the spatial distribution of the emitted anti-atoms. We will discuss the implications of these studies for the major outstanding goal of trapping samples of antihydrogen for precise spectroscopic comparisons with hydrogen. The physics motivations for undertaking these challenging experiments will be briefly recalled.

  13. Cold nuclear fusion device

    International Nuclear Information System (INIS)

    Ogino, Shinji.

    1991-01-01

    Selection of cathode material is a key to the attainment of cold nuclear fusion. However, there are only few reports on the cathode material at present and an effective development has been demanded. The device comprises an anode and a cathode and an electrolytic bath having metal salts dissolved therein and containing heavy water in a glass container. The anode is made of gold or platinum and the cathode is made of metals of V, Sr, Y, Nb, Hf or Ta, and a voltage of 3-25V is applied by way of a DC power source between them. The metal comprising V, Sr, Y, Nb, Hf or Ta absorbs deuterium formed by electrolysis of heavy water effectively to cause nuclear fusion reaction at substantially the same frequency and energy efficiency as palladium and titanium. Accordingly, a cold nuclear fusion device having high nuclear fusion generation frequency can be obtained. (N.H.)

  14. Cold source economic study

    International Nuclear Information System (INIS)

    Fuster, Serge.

    1975-01-01

    This computer code is intended for the statement of the general economic balance resulting from using a given cold source. The balance includes the investments needed for constructing the various materials, and also production balances resulting from their utilization. The case of either using an open circuit condenser on sea or river, or using air cooling systems with closed circuits or as auxiliaries can be dealt with. The program can be used to optimize the characteristics of the various parts of the cold source. The performance of the various materials can be evaluated for a given situation from using very full, precise economic balances, these materials can also be classified according to their possible uses, the outer constraints being taken into account (limits for heat disposal into rivers or seas, water temperature, air temperature). Technical choices whose economic consequences are important have been such clarified [fr

  15. Role of cold surge and MJO on rainfall enhancement over indonesia during east asian winter monsoon

    Science.gov (United States)

    Fauzi, R. R.; Hidayat, R.

    2018-05-01

    Intensity of precipitation in Indonesia is influenced by convection and propagation of southwest wind. Objective of this study is to analyze the relationship between cold surge and the phenomenon of intra-seasonal climate variability Madden-julian Oscillation (MJO) for affecting precipitation in Indonesia. The data used for identifying the occurrence of cold surge are meridional wind speed data from the ERA-Interim. In addition, this study also used RMM1 and RMM2 index data from Bureau of Meteorology (BOM) for identifying MJO events. The results showed that during East Asian Winter Monsoon (EAWM) in 15 years (2000-2015), there are 362 cold surge events, 186 MJO events, and 113 cold surge events were associated with MJO events. The spread of cold surge can penetrate to equator and brought mass of water vapor that causes dominant precipitation in the Indonesian Sea up to 50-75% from climatological precipitation during EAWM. The MJO convection activity that moves from west to east also increases precipitation, but the distribution of rainfall is wider than cold surge, especially in Eastern Indonesia. MJO and cold surge simultaneously can increase rainfall over 100-150% in any Indonesian region that affected by MJO and cold surge events. The mechanism of heavy rainfall is illustrated by high activity of moisture transport in areas such as Java Sea and coastal areas of Indonesia.

  16. The CMS COLD BOX

    CERN Multimedia

    Brice, Maximilien

    2015-01-01

    The CMS detector is built around a large solenoid magnet. This takes the form of a cylindrical coil of superconducting cable that generates a field of 3.8 Tesla: about 100,000 times the magnetic field of the Earth. To run, this superconducting magnet needs to be cooled down to very low temperature with liquid helium. Providing this is the job of a compressor station and the so-called “cold box”.

  17. Clumpy cold dark matter

    Science.gov (United States)

    Silk, Joseph; Stebbins, Albert

    1993-01-01

    A study is conducted of cold dark matter (CDM) models in which clumpiness will inhere, using cosmic strings and textures suited to galaxy formation. CDM clumps of 10 million solar mass/cu pc density are generated at about z(eq) redshift, with a sizable fraction surviving. Observable implications encompass dark matter cores in globular clusters and in galactic nuclei. Results from terrestrial dark matter detection experiments may be affected by clumpiness in the Galactic halo.

  18. Engine Cold Start

    Science.gov (United States)

    2015-09-01

    matching pre- calibrated amplifier • BEI Shaft Encoder (0.2 CAD) • Wolff Instrumented Injector The high speed data was recorded and post-processed by...14. ABSTRACT These fuels were used for testing a GEP 6.5L turbocharged V-8 diesel engine operation in a cold box. This engine architecture is...Z39.18 UNCLASSIFIED UNCLASSIFIED v EXECUTIVE SUMMARY A fuel’s cetane number is very important for the operation of modern diesel

  19. Effects of cold working on the pitting corrosion behavior s of AISI 304 stainless steels

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Kee Min; Kim, Jong Soo; Kim, Young Jun; Kwon, Houk Sang [KAIST, Daejon (Korea, Republic of)

    2015-12-15

    These microstructural changes by cold working can lead improvement of mechanical properties, however from a corrosion resistant point of view, the effects of cold working on the corrosion resistance of stainless steel have been argued. Several studies has been focused on the influence of cold working on the localized corrosion resistance of stainless steels. However, the opinions about the role of cold working on the localized corrosion resistance are highly in consistence. Some studies report that the pitting potential of austenitic stainless steels decreased with cold working level, on the other hands, other studies claimed that the pitting resistance was increased by cold working. Therefore it is necessary to verify how cold working affects pitting corrosion behavior of austenitic stainless steels. In the present work, the influence of cold working on the localized corrosion of AISI 304stainless steel in the neutral chloride solution was studied based on point defect model (PDM). The fraction of deformation-induced martensite was linearly increased with cold rolling level. Through cold rolling, the pitting potential was decreased, the metastable pitting event density was significantly increased and the repassivation potential was decreased. The overall localized corrosion resistance was decreased with cold working, however cold working level increased from 30 % to 50 %, localized corrosion resistance was recovered. The accumulated cation vacancy generates a void at metal/film interface, therefore film breakdown accelerates for cold worked alloys.

  20. Effects of cold working on the pitting corrosion behavior s of AISI 304 stainless steels

    International Nuclear Information System (INIS)

    Jung, Kee Min; Kim, Jong Soo; Kim, Young Jun; Kwon, Houk Sang

    2015-01-01

    These microstructural changes by cold working can lead improvement of mechanical properties, however from a corrosion resistant point of view, the effects of cold working on the corrosion resistance of stainless steel have been argued. Several studies has been focused on the influence of cold working on the localized corrosion resistance of stainless steels. However, the opinions about the role of cold working on the localized corrosion resistance are highly in consistence. Some studies report that the pitting potential of austenitic stainless steels decreased with cold working level, on the other hands, other studies claimed that the pitting resistance was increased by cold working. Therefore it is necessary to verify how cold working affects pitting corrosion behavior of austenitic stainless steels. In the present work, the influence of cold working on the localized corrosion of AISI 304stainless steel in the neutral chloride solution was studied based on point defect model (PDM). The fraction of deformation-induced martensite was linearly increased with cold rolling level. Through cold rolling, the pitting potential was decreased, the metastable pitting event density was significantly increased and the repassivation potential was decreased. The overall localized corrosion resistance was decreased with cold working, however cold working level increased from 30 % to 50 %, localized corrosion resistance was recovered. The accumulated cation vacancy generates a void at metal/film interface, therefore film breakdown accelerates for cold worked alloys

  1. Support for cold neutron utilization

    International Nuclear Information System (INIS)

    Lee, Kye Hong; Han, Young Soo; Choi, Sungmin; Choi, Yong; Kwon, Hoon; Lee, Kwang Hee

    2012-06-01

    - Support for experiments by users of cold neutron scattering instrument - Short-term training of current and potential users of cold neutron scattering instrument for their effective use of the instrument - International collaboration for advanced utilization of cold neutron scattering instruments - Selection and training of qualified instrument scientists for vigorous research endeavors and outstanding achievements in experiments with cold neutron - Research on nano/bio materials using cold neutron scattering instruments - Bulk nano structure measurement using small angle neutron scattering and development of analysis technique

  2. Cold neutron production and application

    International Nuclear Information System (INIS)

    Inoue, Kazuhiko; Watanabe, Noboru.

    1976-01-01

    The first part gives general introduction to cold neutrons, namely the definition and the role as a probe in basic science and technology. The second part reviews various methods of cold neutron production. Some physical characteristics required for cold moderators are presented, and a list summarizes a number of cold moderators and their reactor physics constants. The definition of flux gain factor and the measured values for liquid light- and heavy-hydrogen are also given. The cold neutron spectra in methane and liquid hydrogen measured by LINAC time-of-flight method are presented to show the advantage of solid methane. The cold neutron sources using experimental reactors or linear accelerators are explained along with the examples of existing facilities. Two Japanese programs, the one is the use of a high flux reactor and the other is the use of a LINAC, are also presented. The third part of this report reviews the application areas of cold neutrons. (Aoki, K.)

  3. Cold fusion in perspective

    International Nuclear Information System (INIS)

    Sanford, L.

    1989-01-01

    Since early April a great deal of excitement has been created over the Fleischmann/Pons cold fusion experiment, which if it performs as advertised, could turn out to be mankind's best hope of heading off the energy crisis scheduled for early in the next century. Dozens of groups around the world are now attempting to duplicate the experiment to see if Fleischmann and Pons' discovery is an experimental mistake, an unknown electrochemical effect or a new kind of fusion reaction. This article puts the experiment into the perspective of today and looks at how it might affect the energy scene tomorrow if it should turn out to be commercially exploitable. (author)

  4. Subglacial hydrology of the lake district ice lobe during the Younger Dryas (ca. 12 500 - 11 600 years ago) in the Kylaeniemi area, SE Finland

    Energy Technology Data Exchange (ETDEWEB)

    Lunkka, J. P.; Moisio, K.; Vainio, A. [Univ. of Oulu (Finland)

    2013-07-15

    It is essential to gain knowledge on the subglacial hydrological conditions at the glacier bed / bedrock interface when assessing how bedrock fracture zones affect subglacial melt water flow and in which subglacial zones pressurized and oxygen-rich melt water penetrates into the bedrock fracture systems. In the warm-based glacier zones, a part of subglacial melt water will penetrate deep into the fracture systems although the major part of melt water is drained to and beyond the ice margin via subglacial tunnel networks especially in the areas where ice is flowing on the crystalline bedrock. During the last deglaciation phase of the former Scandinavian Ice Sheet, glaciofluvial accumulations were deposited and these sediment accumulations are highly important when picturing the subglacial hydrology of different ice streams during deglaciation in the crystalline bedrock area. The aim of the present work was to map the bedrock fracture zones in the Kylaeniemi area and to shed light on the subglacial hydrology of the Scandinavian Ice Sheet's Lake District Ice Stream that occupied the Kylaeniemi area during the Younger Dryas between ca. 12 500 - 11 600 years ago. The special emphasis within this general aim was to study the relationship between bedrock fracture zones and the routes of subglacial drainage paths. The methods used to map and study bedrock fracture zones and subglacial drainage paths included remotes sensing methods, field observations, ground penetrating radar (GPR) investigations and GIS-based reconstructions. Conventional geological field methods aided by the GPR-method were also used to map bedrock exposures and their structures and to define the type of glaciofluvial sediments and glaciofluvial landform associations. Two main fracture zone sets occur in the study area. The most prominent bedrock fracture zone set trends NW-SE while the other, less prominent fracture zone set is aligned in NE-SW direction. The majority of the minor joint sets in

  5. Subglacial hydrology of the lake district ice lobe during the Younger Dryas (ca. 12 500 - 11 600 years ago) in the Kylaeniemi area, SE Finland

    International Nuclear Information System (INIS)

    Lunkka, J. P.; Moisio, K.; Vainio, A.

    2013-07-01

    It is essential to gain knowledge on the subglacial hydrological conditions at the glacier bed / bedrock interface when assessing how bedrock fracture zones affect subglacial melt water flow and in which subglacial zones pressurized and oxygen-rich melt water penetrates into the bedrock fracture systems. In the warm-based glacier zones, a part of subglacial melt water will penetrate deep into the fracture systems although the major part of melt water is drained to and beyond the ice margin via subglacial tunnel networks especially in the areas where ice is flowing on the crystalline bedrock. During the last deglaciation phase of the former Scandinavian Ice Sheet, glaciofluvial accumulations were deposited and these sediment accumulations are highly important when picturing the subglacial hydrology of different ice streams during deglaciation in the crystalline bedrock area. The aim of the present work was to map the bedrock fracture zones in the Kylaeniemi area and to shed light on the subglacial hydrology of the Scandinavian Ice Sheet's Lake District Ice Stream that occupied the Kylaeniemi area during the Younger Dryas between ca. 12 500 - 11 600 years ago. The special emphasis within this general aim was to study the relationship between bedrock fracture zones and the routes of subglacial drainage paths. The methods used to map and study bedrock fracture zones and subglacial drainage paths included remotes sensing methods, field observations, ground penetrating radar (GPR) investigations and GIS-based reconstructions. Conventional geological field methods aided by the GPR-method were also used to map bedrock exposures and their structures and to define the type of glaciofluvial sediments and glaciofluvial landform associations. Two main fracture zone sets occur in the study area. The most prominent bedrock fracture zone set trends NW-SE while the other, less prominent fracture zone set is aligned in NE-SW direction. The majority of the minor joint sets in

  6. Positron Plasma Control Techniques Applied to Studies of Cold Antihydrogen

    CERN Document Server

    Funakoshi, Ryo

    2003-01-01

    In the year 2002, two experiments at CERN succeeded in producing cold antihydrogen atoms, first ATHENA and subsequently ATRAP. Following on these results, it is now feasible to use antihydrogen to study the properties of antimatter. In the ATHENA experiment, the cold antihydrogen atoms are produced by mixing large amounts of antiprotons and positrons in a nested Penning trap. The complicated behaviors of the charged particles are controlled and monitored by plasma manipulation techniques. The antihydrogen events are studied using position sensitive detectors and the evidence of production of antihydrogen atoms is separated out with the help of analysis software. This thesis covers the first production of cold antihydrogen in the first section as well as the further studies of cold antihydrogen performed by using the plasma control techniques in the second section.

  7. Event Investigation

    International Nuclear Information System (INIS)

    Korosec, D.

    2000-01-01

    The events in the nuclear industry are investigated from the license point of view and from the regulatory side too. It is well known the importance of the event investigation. One of the main goals of such investigation is to prevent the circumstances leading to the event and the consequences of the event. The protection of the nuclear workers against nuclear hazard, and the protection of general public against dangerous effects of an event could be achieved by systematic approach to the event investigation. Both, the nuclear safety regulatory body and the licensee shall ensure that operational significant events are investigated in a systematic and technically sound manner to gather information pertaining to the probable causes of the event. One of the results should be appropriate feedback regarding the lessons of the experience to the regulatory body, nuclear industry and general public. In the present paper a general description of systematic approach to the event investigation is presented. The systematic approach to the event investigation works best where cooperation is present among the different divisions of the nuclear facility or regulatory body. By involving management and supervisors the safety office can usually improve their efforts in the whole process. The end result shall be a program which serves to prevent events and reduce the time and efforts solving the root cause which initiated each event. Selection of the proper method for the investigation and an adequate review of the findings and conclusions lead to the higher level of the overall nuclear safety. (author)

  8. Microfossils, a Key to Unravel Cold-Water Carbonate Mound Evolution through Time: Evidence from the Eastern Alboran Sea.

    Directory of Open Access Journals (Sweden)

    Claudio Stalder

    Full Text Available Cold-water coral (CWC ecosystems occur worldwide and play a major role in the ocean's carbonate budget and atmospheric CO2 balance since the Danian (~65 m.y. ago. However their temporal and spatial evolution against climatic and oceanographic variability is still unclear. For the first time, we combine the main macrofaunal components of a sediment core from a CWC mound of the Melilla Mounds Field in the Eastern Alboran Sea with the associated microfauna and we highlight the importance of foraminifera and ostracods as indicators of CWC mound evolution in the paleorecord. Abundances of macrofauna along the core reveal alternating periods dominated by distinct CWC taxa (mostly Lophelia pertusa, Madrepora oculata that correspond to major shifts in foraminiferal and ostracod assemblages. The period dominated by M. oculata coincides with a period characterized by increased export of refractory organic matter to the seafloor and rather unstable oceanographic conditions at the benthic boundary layer with periodically decreased water energy and oxygenation, variable bottom water temperature/density and increased sediment flow. The microfaunal and geochemical data strongly suggest that M. oculata and in particular Dendrophylliidae show a higher tolerance to environmental changes than L. pertusa. Finally, we show evidence for sustained CWC growth during the Alleröd-Younger-Dryas in the Eastern Alboran Sea and that this period corresponds to stable benthic conditions with cold/dense and well oxygenated bottom waters, high fluxes of labile organic matter and relatively strong bottom currents.

  9. Cold moderator scattering kernels

    International Nuclear Information System (INIS)

    MacFarlane, R.E.

    1989-01-01

    New thermal-scattering-law files in ENDF format have been developed for solid methane, liquid methane liquid ortho- and para-hydrogen, and liquid ortho- and para-deuterium using up-to-date models that include such effects as incoherent elastic scattering in the solid, diffusion and hindered vibration and rotations in the liquids, and spin correlations for the hydrogen and deuterium. These files were generated with the new LEAPR module of the NJOY Nuclear Data Processing System. Other modules of this system were used to produce cross sections for these moderators in the correct format for the continuous-energy Monte Carlo code (MCNP) being used for cold-moderator-design calculations at the Los Alamos Neutron Scattering Center (LANSCE). 20 refs., 14 figs

  10. Experiments in cold fusion

    International Nuclear Information System (INIS)

    Palmer, E.P.

    1986-01-01

    The work of Steve Jones and others in muon-catalyzed cold fusion of deuterium and hydrogen suggests the possibility of such fusion catalyzed by ions, or combinations of atoms, or more-or-less free electrons in solid and liquid materials. A hint that this might occur naturally comes from the heat generated in volcanic action in subduction zones on the earth. It is questionable whether the potential energy of material raised to the height of a midocean ridge and falling to the depth of an ocean trench can produce the geothermal effects seen in the volcanoes of subduction zones. If the ridge, the trench, the plates, and the asthenosphere are merely visible effects of deeper density-gradient driven circulations, it is still uncertain that observed energy-concentration effects fit the models

  11. SENTINEL EVENTS

    Directory of Open Access Journals (Sweden)

    Andrej Robida

    2004-09-01

    Full Text Available Background. The Objective of the article is a two year statistics on sentinel events in hospitals. Results of a survey on sentinel events and the attitude of hospital leaders and staff are also included. Some recommendations regarding patient safety and the handling of sentinel events are given.Methods. In March 2002 the Ministry of Health introduce a voluntary reporting system on sentinel events in Slovenian hospitals. Sentinel events were analyzed according to the place the event, its content, and root causes. To show results of the first year, a conference for hospital directors and medical directors was organized. A survey was conducted among the participants with the purpose of gathering information about their view on sentinel events. One hundred questionnaires were distributed.Results. Sentinel events. There were 14 reports of sentinel events in the first year and 7 in the second. In 4 cases reports were received only after written reminders were sent to the responsible persons, in one case no reports were obtained. There were 14 deaths, 5 of these were in-hospital suicides, 6 were due to an adverse event, 3 were unexplained. Events not leading to death were a suicide attempt, a wrong side surgery, a paraplegia after spinal anaesthesia, a fall with a femoral neck fracture, a damage of the spleen in the event of pleural space drainage, inadvertent embolization with absolute alcohol into a femoral artery and a physical attack on a physician by a patient. Analysis of root causes of sentinel events showed that in most cases processes were inadequate.Survey. One quarter of those surveyed did not know about the sentinel events reporting system. 16% were having actual problems when reporting events and 47% beleived that there was an attempt to blame individuals. Obstacles in reporting events openly were fear of consequences, moral shame, fear of public disclosure of names of participants in the event and exposure in mass media. The majority of

  12. Monitoring the vaccine cold chain.

    OpenAIRE

    Cheriyan, E

    1993-01-01

    Maintaining the vaccine cold chain is an essential part of a successful immunisation programme. A continuous electronic temperature monitor helped to identify breaks in the cold chain in the community and the study led to the issue of proper guidelines and replacement of faulty equipment.

  13. Cold gelation of globular proteins

    NARCIS (Netherlands)

    Alting, A.C.

    2003-01-01

    Keywords : globular proteins, whey protein, ovalbumin, cold gelation, disulfide bonds, texture, gel hardnessProtein gelation in food products is important to obtain desirable sensory and textural properties. Cold gelation is a novel method to produce protein-based gels. It is a two step process in

  14. Initial heating in cold cars

    NARCIS (Netherlands)

    Daanen, H.A.M.; Teunissen, L.P.J.; Hoogh, I.M. de

    2012-01-01

    During the initial minutes after entering a cold car, people feel uncomfortably cold. Six different warming systems were investigated in a small car in order to find out how to improve the feeling of comfort using 16 volunteers. The methods were: no additional warming next to a standard heating

  15. The status of cold fusion

    Science.gov (United States)

    Storms, E.

    This report attempts to update the status of the phenomenon of cold fusion. The new field is continuing to grow as a variety of nuclear reactions are discovered to occur in a variety of chemical environments at modest temperatures. However, it must be cautioned that most scientists consider cold fusion as something akin to UFO's, ESP, and numerology.

  16. Facts about the Common Cold

    Science.gov (United States)

    ... different viruses. Rhinovirus is the most common cause, accounting for 10 to 40 percent of colds. Other common cold viruses include coronavirus and ... RSS | Terms Of Use | Privacy | Sitemap Our Family Of Sites ... Introduction Risk Factors Screening Symptoms Tumor Testing Summary '; var ...

  17. Effects of cold fronts on ozone in the Houston-Galveston-Brazoria Area

    Science.gov (United States)

    Lei, R.; Talbot, R. W.; Wang, Y.; Wang, S. C.; Estes, M. J.

    2017-12-01

    A cold front may have confounding effects on ozone by bringing in contaminated air masses to an area and causing lower temperatures which likely lead to low ozone production rates. Literature reports on individual cold front events showing increasing and decreasing effects on ozone. The Houston-Galveston-Brazoria (HGB) area as the energy capital of USA suffers relatively high ozone levels. The effect of cold fronts on HGB ozone in the long-term range remains unknown. Weather Prediction Center (WPC) Surface Analysis Archive from National Oceanic and Atmospheric Administration (NOAA) which records cold fronts' positions since 2003 has been employed in this study. The results show the count of cold fronts passing the HGB area shows no clear trend but great interannual variation. Cold front appearance in summer is much less than in other seasons. In general, both mean MDA8 and background ozone during cold front days increased compared non-cold front days. This increasing effect has been enhanced during post-front days and summer season. Cluster analysis on meteorological parameters shows cold front days with high precipitation or wind speed could lower the MDA8 and background ozone but the proportion of those days are low in all cold front days. It may explain why cold fronts show increasing effects on ozone in the HGB area.

  18. Development of cold neutron spectrometers

    International Nuclear Information System (INIS)

    Lee, Changhee; Lee, C. H.; So, J. Y.; Park, S.; Han, Y. S.; Cho, S. J.; Moon, M. K.; Choi, Y. H.; Sun, G. M.

    2012-03-01

    Cold Neutron Triple Axsis Spectrometer (Cold-TAS) Development Ο Fabrication and Installation of the Major Cold-TAS Components Ο Performance Test of the Cold-TAS □ Cold Neutron Time-of-Flight Spectrometer(DC-TOF) Development Ο Fabrication of the Major DC-TOF Components Ο Development DC-TOF Data Reduction Software □ Expected Contribution The two world-class inelastic neutron scattering instruments measure atomic or molecular scale dynamics of meV energy range. This unprecedented measurement capability in the country will enable domestic and international scientists to observe new phenomena in their materials research to obtain world class results. Especially those who work in the fields of magnetic properties of superconductors and multiferroics, molecular dynamics, etc. will get more benefit from these two instruments

  19. Event Modeling

    DEFF Research Database (Denmark)

    Bækgaard, Lars

    2001-01-01

    The purpose of this chapter is to discuss conceptual event modeling within a context of information modeling. Traditionally, information modeling has been concerned with the modeling of a universe of discourse in terms of information structures. However, most interesting universes of discourse...... are dynamic and we present a modeling approach that can be used to model such dynamics.We characterize events as both information objects and change agents (Bækgaard 1997). When viewed as information objects events are phenomena that can be observed and described. For example, borrow events in a library can...

  20. Cold fusion method

    International Nuclear Information System (INIS)

    Takahashi, Akihito.

    1994-01-01

    A Pt wire electrode is supported from the periphery relative to a Pd electrode by way of a polyethylene or teflon plate in heavy water, and electrolysis is applied while varying conditions successively in a sawteeth fashion at an initial stage, and after elapse of about one week, a pulse current is supplied to promote nuclear reaction and to generate excess heat greater than a charged electric power. That is, small amount of neutron emission is increased and electrolytic cell temperature is elevated by varying the electrolysis conditions successively in the sawteeth fashion at the initial stage. In addition, when the pulse electric current is supplied after elapse of about one week, the electrolytic cell temperature is abnormally elevated, so that the promotion of nuclear reaction phenomenon and the generation of excess heat greater than the charged electric power are recognized. Then, a way to control power level and time fluctuation of cold fusion is attained, thereby contributing to development of a further method for generating excess heat as desired. In addition, it contributes to a development for a method of obtaining such an excess heat that can be taken as a new energy. (N.H.)

  1. Cold Rydberg molecules

    Science.gov (United States)

    Raithel, Georg; Zhao, Jianming

    2017-04-01

    Cold atomic systems have opened new frontiers at the interface of atomic and molecular physics. These include research on novel types of Rydberg molecules. Three types of molecules will be reviewed. Long-range, homonuclear Rydberg molecules, first predicted in [1] and observed in [2], are formed via low-energy electron scattering of the Rydberg electron from a ground-state atom within the Rydberg atom's volume. The binding mostly arises from S- and P-wave triplet scattering. We use a Fermi model that includes S-wave and P-wave singlet and triplet scattering, the fine structure coupling of the Rydberg atom and the hyperfine structure coupling of the 5S1/2 atom (in rubidium [3]). The hyperfine structure gives rise to mixed singlet-triplet potentials for both low-L and high-L Rydberg molecules [3]. A classification into Hund's cases [3, 4, 5] will be discussed. The talk further includes results on adiabatic potentials and adiabatic states of Rydberg-Rydberg molecules in Rb and Cs. These molecules, which have even larger bonding length than Rydberg-ground molecules, are formed via electrostatic multipole interactions. The leading interaction term of neutral Rydberg-Rydberg molecules is between two dipoles, while for ionic Rydberg molecules it is between a dipole and a monopole. NSF (PHY-1506093), NNSF of China (61475123).

  2. Cold-Adapted Enzymes

    Science.gov (United States)

    Georlette, D.; Bentahir, M.; Claverie, P.; Collins, T.; D'amico, S.; Delille, D.; Feller, G.; Gratia, E.; Hoyoux, A.; Lonhienne, T.; Meuwis, M.-a.; Zecchinon, L.; Gerday, Ch.

    In the last few years, increased attention has been focused on enzymes produced by cold-adapted micro-organisms. It has emerged that psychrophilic enzymes represent an extremely powerful tool in both protein folding investigations and for biotechnological purposes. Such enzymes are characterised by an increased thermosensitivity and, most of them, by a higher catalytic efficiency at low and moderate temperatures, when compared to their mesophilic counterparts. The high thermosensitivity probably originates from an increased flexibility of either a selected area of the molecular edifice or the overall protein structure, providing enhanced abilities to undergo conformational changes during catalysis at low temperatures. Structure modelling and recent crystallographic data have allowed to elucidate the structural parameters that could be involved in this higher resilience. It was demonstrated that each psychrophilic enzyme adopts its own adaptive strategy. It appears, moreover, that there is a continuum in the strategy of protein adaptation to temperature, as the previously mentioned structural parameters are implicated in the stability of thermophilic proteins. Additional 3D crystal structures, site-directed and random mutagenesis experiments should now be undertaken to further investigate the stability-flexibility-activity relationship.

  3. Cold-formed steel design

    CERN Document Server

    Yu, Wei-Wen

    2010-01-01

    The definitive text in the field, thoroughly updated and expanded Hailed by professionals around the world as the definitive text on the subject, Cold-Formed Steel Design is an indispensable resource for all who design for and work with cold-formed steel. No other book provides such exhaustive coverage of both the theory and practice of cold-formed steel construction. Updated and expanded to reflect all the important developments that have occurred in the field over the past decade, this Fourth Edition of the classic text provides you with more of the detailed, up-to-the-minute techni

  4. Liquefied petroleum gas cold burn sustained while refueling a car.

    Science.gov (United States)

    Scarr, Bronwyn; Mitra, Biswadev; Maini, Amit; Cleland, Heather

    2010-02-01

    There have been few cases of cold burn related to the exposure of liquid petroleum gas (LPG). We present the case of a young woman exposed to LPG while refueling her car who sustained partial thickness burns to the dorsum of her hand. Contact with LPG leaking from a pressurized system causes tissue damage because of cold injury. Immediate management of LPG is extrapolated from the management of frostbite. The increasing use of LPG mandates an awareness of prevention strategies and management principles in the setting of adverse events.

  5. The structure and energetics of midlatitude disturbances accompanying cold-air outbreaks over East Asia

    Science.gov (United States)

    Lau, N.-C.; Lau, K.-M.

    1984-01-01

    The evolution of extratropical transient waves as they propagate eastward from the Eurasian land mass toward the Pacific during selected cold surge events in the winter Monsoon Experiment (MONEX) is studied. The outstanding cold surge episodes during MONEX are first identified, and the salient synoptic features related to these events are described using composite streamline charts. The structure of rapidly varying disturbances accompanying the cold surges and the associated energetics are examined, and the behavior of those fluctuations over relatively longer time scales is addressed.

  6. Cold fronts and reservoir limnology: an integrated approach towards the ecological dynamics of freshwater ecosystems.

    Science.gov (United States)

    Tundisi, J G; Matsumura-Tundisi, T; Pereira, K C; Luzia, A P; Passerini, M D; Chiba, W A C; Morais, M A; Sebastien, N Y

    2010-10-01

    In this paper the authors discuss the effects of cold fronts on the dynamics of freshwater ecosystems of southeast South America. Cold fronts originating from the Antarctic show a monthly frequency that promotes turbulence and vertical mixing in reservoirs with a consequence to homogenize nutrient distribution, dissolved oxygen and temperature. Weak thermoclines and the athelomixis process immediately before, during and after the passage of cold fronts interfere with phytoplankton succession in reservoirs. Cyanobacteria blooms in eutrophic reservoirs are frequently connected with periods of stratification and stability of the water column. Cold fronts in the Amazon and Pantanal lakes may produce fish killings during the process of "friagem" associated mixing events. Further studies will try to implement a model to predict the impact of cold fronts and prepare management procedures in order to cope with cyanobacteria blooms during warm and stable water column periods. Changes in water quality of reservoirs are expected during circulation periods caused by cold fronts.

  7. Cold fronts and reservoir limnology: an integrated approach towards the ecological dynamics of freshwater ecosystems

    Directory of Open Access Journals (Sweden)

    JG. Tundisi

    Full Text Available In this paper the authors discuss the effects of cold fronts on the dynamics of freshwater ecosystems of southeast South America. Cold fronts originating from the Antarctic show a monthly frequency that promotes turbulence and vertical mixing in reservoirs with a consequence to homogenize nutrient distribution, dissolved oxygen and temperature. Weak thermoclines and the athelomixis process immediately before, during and after the passage of cold fronts interfere with phytoplankton succession in reservoirs. Cyanobacteria blooms in eutrophic reservoirs are frequently connected with periods of stratification and stability of the water column. Cold fronts in the Amazon and Pantanal lakes may produce fish killings during the process of "friagem" associated mixing events. Further studies will try to implement a model to predict the impact of cold fronts and prepare management procedures in order to cope with cyanobacteria blooms during warm and stable water column periods. Changes in water quality of reservoirs are expected during circulation periods caused by cold fronts.

  8. Main processes of the Atlantic cold tongue interannual variability

    Science.gov (United States)

    Planton, Yann; Voldoire, Aurore; Giordani, Hervé; Caniaux, Guy

    2018-03-01

    The interannual variability of the Atlantic cold tongue (ACT) is studied by means of a mixed-layer heat budget analysis. A method to classify extreme cold and warm ACT events is proposed and applied to ten various analysis and reanalysis products. This classification allows 5 cold and 5 warm ACT events to be selected over the period 1982-2007. Cold (warm) ACT events are defined by the presence of negative (positive) sea surface temperature (SST) anomalies at the center of the equatorial Atlantic in late boreal spring, preceded by negative (positive) zonal wind stress anomalies in the western equatorial Atlantic. An ocean general circulation model capable of reconstructing the interannual variability of the ACT correctly is used to demonstrate that cold ACT events develop rapidly from May to June mainly due to intense cooling by vertical mixing and horizontal advection. The simulated cooling at the center of the basin is the result of the combined effects of non-local and local processes. The non-local process is an upwelling associated with an eastward-propagating Kelvin wave, which makes the mixed-layer more shallow and preconditions the upper layers to be cooled by an intense heat loss at the base of the mixed-layer, which is amplified by a stronger local injection of energy from the atmosphere. The early cooling by vertical mixing in March is also shown to be a good predictor of June cooling. In July, horizontal advection starts to warm the mixed-layer abnormally and damps SST anomalies. The advection anomalies, which result from changes in the horizontal temperature gradient, are associated in some cases with the propagation of Rossby waves along the equator. During warm ACT events, processes are reversed, generating positive SST anomalies: a downwelling Kelvin wave triggers stratification anomalies and mixed-layer depth anomalies, amplified by a weaker injection of energy from the atmosphere in May-June. In July, warm ACT events are abnormally cooled due to

  9. Cold nuclear fusion

    Energy Technology Data Exchange (ETDEWEB)

    Tsyganov, E.N., E-mail: edward.tsyganov@coldfusion-power.com [Cold Fusion Power, International (United States); Bavizhev, M.D. [LLC “Radium”, Moscow (Russian Federation); Buryakov, M.G. [Joint Institute for Nuclear Research (JINR), Dubna (Russian Federation); Dabagov, S.B. [RAS P.N. Lebedev Physical Institute, Leninsky pr. 53, 119991 Moscow (Russian Federation); National Research Nuclear University MEPhI, Kashirskoe shosse 31, 115409 Moscow (Russian Federation); Golovatyuk, V.M.; Lobastov, S.P. [Joint Institute for Nuclear Research (JINR), Dubna (Russian Federation)

    2015-07-15

    If target deuterium atoms were implanted in a metal crystal in accelerator experiments, a sharp increase in the probability of DD-fusion reaction was clearly observed when compared with the reaction’s theoretical value. The electronic screening potential, which for a collision of free deuterium atoms is about 27 eV, reached 300–700 eV in the case of the DD-fusion in metallic crystals. These data leads to the conclusion that a ban must exist for deuterium atoms to be in the ground state 1s in a niche filled with free conduction electrons. At the same time, the state 2p whose energy level is only 10 eV above that of state 1s is allowed in these conditions. With anisotropy of 2p, 3p or above orbitals, their spatial positions are strictly determined in the lattice coordinate system. When filling out the same potential niches with two deuterium atoms in the states 2p, 3p or higher, the nuclei of these atoms can be permanently positioned without creating much Coulomb repulsion at a very short distance from each other. In this case, the transparency of the potential barrier increases dramatically compared to the ground state 1s for these atoms. The probability of the deuterium nuclei penetrating the Coulomb barrier by zero quantum vibration of the DD-system also increases dramatically. The so-called cold nuclear DD-fusion for a number of years was registered in many experiments, however, was still rejected by mainstream science for allegedly having no consistent scientific explanation. Finally, it received the validation. Below, we outline the concept of this explanation and give the necessary calculations. This paper also considers the further destiny of the formed intermediate state of {sup 4}He{sup ∗}.

  10. Phonon forces and cold denaturatio

    DEFF Research Database (Denmark)

    Bohr, Jakob

    2003-01-01

    Protein unfolds upon temperature reduction as Well as upon In increase in temperature, These phenomena are called cold denaturation and hot denaturation, respectively. The contribution from quantum mode forces to denaturation is estimated using a simple phenomenological model describing the molec......Protein unfolds upon temperature reduction as Well as upon In increase in temperature, These phenomena are called cold denaturation and hot denaturation, respectively. The contribution from quantum mode forces to denaturation is estimated using a simple phenomenological model describing...... the molecule Is a continuum. The frequencies of the vibrational modes depend on the molecular dimensionality; hence, the zero-point energies for the folded and the denatured protein are estimated to differ by several electron volts. For a biomolecule such an energy is significant and may contribute to cold...... denaturing. This is consistent with the empirical observation that cold denaturation is exothermic anti hot denaturation endothermic....

  11. Cold Weather and Cardiovascular Disease

    Science.gov (United States)

    ... Venous Thromboembolism Aortic Aneurysm More Cold Weather and Cardiovascular Disease Updated:Sep 16,2015 Th is winter ... and procedures related to heart disease and stroke. Cardiovascular Conditions • Conditions Home • Arrhythmia and Atrial Fibrillation • Cardiac ...

  12. Magnesium Repair by Cold Spray

    National Research Council Canada - National Science Library

    Champagne, V. K; Leyman, P.F; Helfritch, D. J

    2008-01-01

    .... Army Research Laboratory has developed a cold spray process to reclaim magnesium components that shows significant improvement over existing methods and is in the process of qualification for use on rotorcraft...

  13. Nonfreezing Cold-Induced Injuries

    Science.gov (United States)

    2012-01-01

    cold injury. ( Modi - fi ed from Jia J, Pollock M: The pathogenesis of non-freezing cold nerve injury: Observations in the rat, Brain 120:631, 1997...myelitis and sinus development ( Figures 7-17 to 7-19 ). Appearance and behavior of the neuropathic foot have many similarities to those of the diabetic ...foot. In the diabetic foot, infections tend to be polymicrobial with Staphylococcus aureus, Staphylococcus epidermidis, and Enterococcus and

  14. Tip model of cold fission

    International Nuclear Information System (INIS)

    Goennenwein, F.; Boersig, B.

    1991-01-01

    Cold fission is defined to be the limiting case of nuclear fission where virtually all of the available energy is converted into the total kinetic energy of the fragments. The fragments have, therefore, to be born in or at least close to their respective ground states. Starting from the viewpoint that cold fission corresponds to most compact scission configurations, energy constraints have been exploited to calculate minimum tip distances between the two nascent fragments in binary fission. Crucial input parameters to this tip model of cold fission are the ground-state deformations of fragment nuclei. It is shown that the minimum tip distances being compatible with energy conservation vary strongly with both the mass and charge fragmentation of the fission prone nucleus. The tip distances refer to nuclei with equivalent sharp surfaces. In keeping with the size of the surface width of leptodermous nuclei, only configurations where the tip distances are smaller than a few fm may be considered as valid scission configurations. From a comparison with experimental data on cold fission this critical tip distance appears to be 3.0 fm for the model parameters chosen. Whenever the model calculation yields tip distances being smaller than the critical value, a necessary condition for attaining cold fission is considered to be fulfilled. It is shown that this criterion allows to understand in fair agreement with experiment which mass fragmentations are susceptible to lead to cold fission and which fragment-charge divisions are the most favored in each isobaric mass chain. Being based merely on energy arguments, the model cannot aim at predicting fragment yields in cold fission. However, the tip model proposed appears well suited to delineate the phase space where cold fission phenomena may come into sight. (orig.)

  15. Cold urticaria. Dissociation of cold-evoked histamine release and urticara following cold challenge.

    Science.gov (United States)

    Keahey, T M; Greaves, M W

    1980-02-01

    Nine patients with acquired cold urticaria were studied to assess the effects of beta-adrenergic agents, xanthines, and corticosteroids on cold-evoked histamine release from skin in vivo. The patients, in all of whom an immediate urticarial response developed after cooling of the forearm, demonstrated release of histamine into the venous blood draining that forearm. Following treatment with aminophylline and albuterol in combination or prednisone alone, suppression of histamine release occurred in all but one patient. In some patients, this was accompanied by a subjective diminution in pruritus or buring, but there was no significant improvement in the ensuing edema or erythema. In one patient, total suppression of histamine release was achieved without any effect on whealing and erythema in response to cold challenge. Our results suggest that histamine is not central to the pathogenesis of vascular changes in acquired cold urticaria.

  16. Cold acclimation and cognitive performance: A review.

    Science.gov (United States)

    Jones, Douglas M; Bailey, Stephen P; Roelands, Bart; Buono, Michael J; Meeusen, Romain

    2017-12-01

    Athletes, occupational workers, and military personnel experience cold temperatures through cold air exposure or cold water immersion, both of which impair cognitive performance. Prior work has shown that neurophysiological pathways may be sensitive to the effects of temperature acclimation and, therefore, cold acclimation may be a potential strategy to attenuate cold-induced cognitive impairments for populations that are frequently exposed to cold environments. This review provides an overview of studies that examine repeated cold stress, cold acclimation, and measurements of cognitive performance to determine whether or not cold acclimation provides beneficial protection against cold-induced cognitive performance decrements. Studies included in this review assessed cognitive measures of reaction time, attention, logical reasoning, information processing, and memory. Repeated cold stress, with or without evidence of cold acclimation, appears to offer no added benefit of improving cognitive performance. However, research in this area is greatly lacking and, therefore, it is difficult to draw any definitive conclusions regarding the use of cold acclimation to improve cognitive performance during subsequent cold exposures. Given the current state of minimal knowledge on this topic, athletes, occupational workers, and military commands looking to specifically enhance cognitive performance in cold environments would likely not be advised to spend the time and effort required to become acclimated to cold. However, as more knowledge becomes available in this area, recommendations may change. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Lightning and severe thunderstorms in event management.

    Science.gov (United States)

    Walsh, Katie M

    2012-01-01

    There are a few national position stands/guidelines that address environmental conditions in athletics, yet they do not govern all outdoor sports. Extreme heat and cold, lightning, and severe wind can all be fatal, yet the majority of outdoor sports have no published guidelines addressing these conditions in relation to activity. Available research on extreme heat and cold conditions in athletics provides prevention strategies, to include acclimatization. Lightning and severe wind are two environmental conditions to which humans cannot accommodate, and they both can be deadly. There are strong positions on extreme heat/cold and lightning safety in athletics, but none affiliated with severe winds. Medical personnel involved in planning large outdoor sporting events must know of the presence of nationally published weather-related documents and apply them to their event. In addition, research needs to be expanded in the realm of establishing guidelines for safety to participants and spectators in severe wind conditions.

  18. Fusion events

    International Nuclear Information System (INIS)

    Aboufirassi, M; Angelique, J.C.; Bizard, G.; Bougault, R.; Brou, R.; Buta, A.; Colin, J.; Cussol, D.; Durand, D.; Genoux-Lubain, A.; Horn, D.; Kerambrun, A.; Laville, J.L.; Le Brun, C.; Lecolley, J.F.; Lefebvres, F.; Lopez, O.; Louvel, M.; Meslin, C.; Metivier, V.; Nakagawa, T.; Peter, J.; Popescu, R.; Regimbart, R.; Steckmeyer, J.C.; Tamain, B.; Vient, E.; Wieloch, A.; Yuasa-Nakagawa, K.

    1998-01-01

    The fusion reactions between low energy heavy ions have a very high cross section. First measurements at energies around 30-40 MeV/nucleon indicated no residue of either complete or incomplete fusion, thus demonstrating the disappearance of this process. This is explained as being due to the high amount o energies transferred to the nucleus, what leads to its total dislocation in light fragments and particles. Exclusive analyses have permitted to mark clearly the presence of fusion processes in heavy systems at energies above 30-40 MeV/nucleon. Among the complete events of the Kr + Au reaction at 60 MeV/nucleon the majority correspond to binary collisions. Nevertheless, for the most considerable energy losses, a class of events do occur for which the detected fragments appears to be emitted from a unique source. These events correspond to an incomplete projectile-target fusion followed by a multifragmentation. Such events were singled out also in the reaction Xe + Sn at 50 MeV/nucleon. For the events in which the energy dissipation was maximal it was possible to isolate an isotropic group of events showing all the characteristics of fusion nuclei. The fusion is said to be incomplete as pre-equilibrium Z = 1 and Z = 2 particles are emitted. The cross section is of the order of 25 mb. Similar conclusions were drown for the systems 36 Ar + 27 Al and 64 Zn + nat Ti. A cross section value of ∼ 20 mb was determined at 55 MeV/nucleon in the first case, while the measurement of evaporation light residues in the last system gave an upper limit of 20-30 mb for the cross section at 50 MeV/nucleon

  19. Thermo-mechanical Design Methodology for ITER Cryodistribution cold boxes

    Science.gov (United States)

    Shukla, Vinit; Patel, Pratik; Das, Jotirmoy; Vaghela, Hitensinh; Bhattacharya, Ritendra; Shah, Nitin; Choukekar, Ketan; Chang, Hyun-Sik; Sarkar, Biswanath

    2017-04-01

    The ITER cryo-distribution (CD) system is in charge of proper distribution of the cryogen at required mass flow rate, pressure and temperature level to the users; namely the superconducting (SC) magnets and cryopumps (CPs). The CD system is also capable to use the magnet structures as a thermal buffer in order to operate the cryo-plant as much as possible at a steady state condition. A typical CD cold box is equipped with mainly liquid helium (LHe) bath, heat exchangers (HX’s), cryogenic valves, filter, heaters, cold circulator, cold compressor and process piping. The various load combinations which are likely to occur during the life cycle of the CD cold boxes are imposed on the representative model and impacts on the system are analyzed. This study shows that break of insulation vacuum during nominal operation (NO) along with seismic event (Seismic Level-2) is the most stringent load combination having maximum stress of 224 MPa. However, NO+SMHV (Séismes Maximaux Historiquement Vraisemblables = Maximum Historically Probable Earthquakes) load combination is having the least safety margin and will lead the basis of the design of the CD system and its sub components. This paper presents and compares the results of different load combinations which are likely to occur on a typical CD cold box.

  20. High Latitude Corals Tolerate Severe Cold Spell

    Directory of Open Access Journals (Sweden)

    Chenae A. Tuckett

    2018-01-01

    Full Text Available Climatically extreme weather events often drive long-term ecological responses of ecosystems. By disrupting the important symbiosis with zooxanthellae, Marine Cold Spells (MCS can cause bleaching and mortality in tropical and subtropical scleractinian corals. Here we report on the effects of a severe MCS on high latitude corals, where we expected to find bleaching and mortality. The MCS took place off the coast of Perth (32°S, Western Australia in 2016. Bleaching was assessed before (2014 and after (2017 the MCS from surveys of permanent plots, and with timed bleaching searches. Temperature data was recorded with in situ loggers. During the MCS temperatures dipped to the coldest recorded in ten years (15.3°C and periods of <17°C lasted for up to 19 days. Only 4.3% of the surveyed coral colonies showed signs of bleaching. Bleaching was observed in 8 species where those most affected were Plesiastrea versipora and Montipora mollis. These findings suggest that high latitude corals in this area are tolerant of cold stress and are not persisting near a lethal temperature minimum. It has not been established whether other environmental conditions are limiting these species, and if so, what the implications are for coral performance on these reefs in a warmer future.

  1. Cold weather effects on Dresden Unit 1

    Energy Technology Data Exchange (ETDEWEB)

    Anagnostopoulos, H. [Commonwealth Edison Co., Morris, IL (United States)

    1995-03-01

    Dresden Unit 1 is in the final stages of a decommissioning effort directed at preparing the unit to enter a SAFSTOR status. Following an extended sub-zero cold wave, about 55,000 gallons of water were discovered in the lowest elevation of the spherical reactor enclosure. Cold weather had caused the freezing and breaking of several service water lines that had not been completely isolated. Two days later, at a regularly scheduled decommissioning meeting, the event was communicated to the decommissioning team, who quickly recognized the potential for freezing of a 42 inches diameter Fuel Transfer Tube that connects the sphere to the Spent Fuel Pool. The team directed that the pool gates between the adjacent Spent Fuel Pool and the Fuel Transfer Pool be installed, and a portable source of heat was installed on the Fuel Transfer Tube. It was later determined that, with the fuel pool gates removed, and with a worst case freeze break at the 502 elevation on the Fuel Transfer Tube (in the Sphere), the fuel in the Spent Fuel Pool could be uncovered to a level 3 below the top of active fuel.

  2. Cold transfer between deformed, Coulomb excited nuclei

    International Nuclear Information System (INIS)

    Bauer, H.

    1998-01-01

    The scattering system 162 Dy → 116 Sn has been examined at energies in the vicinity of the Coulomb barrier using the Heidelberg-Darmstadt Crystal Ball spectrometer combined with 5 Germanium-CLUSTER detectors. In order to study pairing correlations as a function of angular momentum cold events were selected in the 2n stripping channel by identifying and suppressing the dominant hot part of the transfer with the Crystal Ball. The CLUSTER detectors with their high γ-efficiency were used to identify the transfer channel and to resolve individual final states. Cross sections for the population of individual yrast states in a cold transfer reaction have been measured for the first time indicating the strong influence of higher transfer multipolarities. At small surface distances Coulomb-nuclear interferences were found to be responsible for the stronger decline of the population of higher yrast states in the transfer channel as compared to the Coulex channel. As a preparatory study for 2n transfer measurements between high spin yrast states in the backbending region of deformed nuclei the Coulomb excitation process in the crossing region of two bands in 162 Dy has been analyzed. The gross properties of the measured population probabilities could be interpreted in a simple band mixing model. (orig.)

  3. 77 FR 43117 - Meeting of the Cold War Advisory Committee for the Cold War Theme Study

    Science.gov (United States)

    2012-07-23

    ... the Cold War Advisory Committee for the Cold War Theme Study AGENCY: National Park Service, Interior... Committee Act, 5 U.S.C. Appendix, that the Cold War Advisory Committee for the Cold War Theme Study will... National Park Service (NPS) concerning the Cold War Theme Study. DATES: The teleconference meeting will be...

  4. Spectroscopy with cold and ultra-cold neutrons

    Directory of Open Access Journals (Sweden)

    Abele Hartmut

    2015-01-01

    Full Text Available We present two new types of spectroscopy methods for cold and ultra-cold neutrons. The first method, which uses the R×B drift effect to disperse charged particles in a uniformly curved magnetic field, allows to study neutron β-decay. We aim for a precision on the 10−4 level. The second method that we refer to as gravity resonance spectroscopy (GRS allows to test Newton’s gravity law at short distances. At the level of precision we are able to provide constraints on any possible gravity-like interaction. In particular, limits on dark energy chameleon fields are improved by several orders of magnitude.

  5. Hesitant birth of cold fusion

    International Nuclear Information System (INIS)

    Bockris, J.O.

    1992-01-01

    John O'M. Bockris, a distinguished chemistry professor at Texas A ampersand M University, finds the reaction to the announcement of the discovery of cold fusion curious. Two years earlier, he notes, there had been a comparable announcement concerning the discovery of high-temperature superconductivity; it received favorable press coverage for months. The cold-fusion announcement, on the other hand, was met with dour skepticism. When other researchers failed in efforts to duplicate the findings of Martin Fleischmann and B. Stanley Pons, Bockris says, the two scientists were held up to ridicule. Bockris says he found a deep emotional opposition to cold fusion, even within his own department and university. This opposition is fueled in large part, he believes, by big science and the hot fusion lobby. A key indicator of cold fusion is the presence of tritium, Brockis claims. At Texas A ampersand M, large amounts of tritium have been found in some experiments; this also has occurred in experiments at more than 40 laboratories in nine countries, he says. Excess heat production is more difficult to attain, he acknowledges. The cold-fusion controversy has uncovered some unflattering characteristics of the scientific community, Bockris says. Among them are: scientists are no less driven by emotion that business people or politicians; research funding decisions serve to perpetuate the goals of politically powerful interest groups; and ideas have great inertia once planted in a scientist's mind

  6. Steel weldability. Underbead cold cracking

    International Nuclear Information System (INIS)

    Marquet, F.; Defourny, J.; Bragard, A.

    1977-01-01

    The problem of underbead cold cracking has been studied by the implant technique. This approach allows to take into account in a quantitative manner the different factors acting on the cold cracking phenomenon: structure under the weld bead, level of restraint, hydrogen content in the molten metal. The influence of the metallurgical factors depending from the chemical composition of the steel has been examined. It appeared that carbon equivalent is an important factor to explain cold cracking sensitivity but that it is not sufficient to characterize the steel. The results have shown that vanadium may have a deleterious effect on the resistance to cold cracking when the hydrogen content is high and that small silicon additions are beneficient. The influence of the diffusible hydrogen content has been checked and the important action of pre- and postheating has been shown. These treatments allow the hydrogen to escape from the weld before the metal has been damaged. Some inclusions (sulphides) may also decrease the influence of hydrogen. A method based on the implant tests has been proposed which allows to choose and to control safe welding conditions regarding cold cracking

  7. Perspective Research Progress in Cold Responses of Capsella bursa-pastoris

    Directory of Open Access Journals (Sweden)

    Ali Noman

    2017-08-01

    Full Text Available Plants respond to cold stress by modulating biochemical pathways and array of molecular events. Plant morphology is also affected by the onset of cold conditions culminating at repression in growth as well as yield reduction. As a preventive measure, cascades of complex signal transduction pathways are employed that permit plants to endure freezing or chilling periods. The signaling pathways and related events are regulated by the plant hormonal activity. Recent investigations have provided a prospective understanding about plant response to cold stress by means of developmental pathways e.g., moderate growth involved in cold tolerance. Cold acclimation assays and bioinformatics analyses have revealed the role of potential transcription factors and expression of genes like CBF, COR in response to low temperature stress. Capsella bursa-pastoris is a considerable model plant system for evolutionary and developmental studies. On different occasions it has been proved that C. bursa-pastoris is more capable of tolerating cold than A. thaliana. But, the mechanism for enhanced low or freezing temperature tolerance is still not clear and demands intensive research. Additionally, identification and validation of cold responsive genes in this candidate plant species is imperative for plant stress physiology and molecular breeding studies to improve cold tolerance in crops. We have analyzed the role of different genes and hormones in regulating plant cold resistance with special reference to C. bursa-pastoris. Review of collected data displays potential ability of Capsella as model plant for improvement in cold stress regulation. Information is summarized on cold stress signaling by hormonal control which highlights the substantial achievements and designate gaps that still happen in our understanding.

  8. Public Perception of Extreme Cold Weather-Related Health Risk in a Cold Area of Northeast China.

    Science.gov (United States)

    Ban, Jie; Lan, Li; Yang, Chao; Wang, Jian; Chen, Chen; Huang, Ganlin; Li, Tiantian

    2017-08-01

    A need exists for public health strategies regarding extreme weather disasters, which in recent years have become more frequent. This study aimed to understand the public's perception of extreme cold and its related health risks, which may provide detailed information for public health preparedness during an extreme cold weather event. To evaluate public perceptions of cold-related health risk and to identify vulnerable groups, we collected responses from 891 participants in a face-to-face survey in Harbin, China. Public perception was measured by calculating the score for each perception question. Locals perceived that extreme cold weather and related health risks were serious, but thought they could not avoid these risks. The significant difference in perceived acceptance level between age groups suggested that the elderly are a "high health risk, low risk perception" group, meaning that they are relatively more vulnerable owing to their high susceptibility and low awareness of the health risks associated with extreme cold weather. The elderly should be a priority in risk communication and health protective interventions. This study demonstrated that introducing risk perception into the public health field can identify vulnerable groups with greater needs, which may improve the decision-making of public health intervention strategies. (Disaster Med Public Health Preparedness. 2017;11:417-421).

  9. Reply to comment by E. Bard et al. on "Younger Dryas sea level and meltwater pulse 1B recorded in Barbados reef crest coral Acropora palmata" by N. A. Abdul et al.

    Science.gov (United States)

    Mortlock, Richard A.; Abdul, Nicole A.; Wright, James D.; Fairbanks, Richard G.

    2016-12-01

    Abdul et al. (2016) presented a detailed record of sea level at Barbados (13.9-9 kyr B.P.) tightly constraining the timing and amplitude during the Younger Dryas and Meltwater Pulse 1B (MWP-1B) based on U-Th dated reef crest coral species Acropora palmata. The Younger Dryas slow stand and the large (14 m) rapid sea level jump are not resolved in the Tahiti record. Tahiti sea level estimates are remarkably close to the Barbados sea level curve between 13.9 and 11.6 kyr but fall below the Barbados sea level curve for a few thousand years following MWP-1B. By 9 kyr the Tahiti sea level estimates again converge with the Barbados sea level curve. Abdul et al. (2016) concluded that Tahiti reefs at the core sites did not keep up with intervals of rapidly rising sea level during MWP-1B. We counter Bard et al. (2016) by showing (1) that there is no evidence for a hypothetical fault in Oistins Bay affecting one of the Barbados coring locations, (2) that the authors confuse the rare occurrences of A. palmata at depths >5 m with the "thickets" of A. palmata fronds representing the reef-crest facies, and (3) that uncertainties in depth habitat proxies largely account for differences in Barbados and Tahiti sea level differences curves with A. palmata providing the most faithful proxy. Given the range in Tahiti paleodepth uncertainties at the cored sites, the most parsimonious explanation remains that Tahiti coralgal ridges did not keep up with the sea level rise of MWP-1B.

  10. The Recent Atlantic Cold Anomaly: Causes, Consequences, and Related Phenomena

    Science.gov (United States)

    Josey, Simon A.; Hirschi, Joel J.-M.; Sinha, Bablu; Duchez, Aurélie; Grist, Jeremy P.; Marsh, Robert

    2018-01-01

    Cold ocean temperature anomalies have been observed in the mid- to high-latitude North Atlantic on interannual to centennial timescales. Most notably, a large region of persistently low surface temperatures accompanied by a sharp reduction in ocean heat content was evident in the subpolar gyre from the winter of 2013-2014 to 2016, and the presence of this feature at a time of pervasive warming elsewhere has stimulated considerable debate. Here, we review the role of air-sea interaction and ocean processes in generating this cold anomaly and place it in a longer-term context. We also discuss the potential impacts of surface temperature anomalies for the atmosphere, including the North Atlantic Oscillation and European heat waves; contrast the behavior of the Atlantic with the extreme warm surface event that occurred in the North Pacific over a similar timescale; and consider the possibility that these events represent a response to a change in atmospheric planetary wave forcing.

  11. Observation for really cold fragmentation of heavy nucleus

    International Nuclear Information System (INIS)

    Goverdovskij, A.A.; Ketlerov, V.V.; Mitrofanov, V.F.; Ostapenko, Yu.B.; Khryachkov, V.A.

    1998-01-01

    The results of the detailed study on mass-energy charged correlations of the thorium-232 fission fragments, produced by the 5 MeV neutrons are presented. The event of the thorium nucleus really cold fragmentation into tellurium-134 and strontium-99 at the basic quantum states is identified. It is shown that the whole reaction energy is exhausted by the motion kinetic energy of the fragments in the mutual field

  12. Acetaminophen (paracetamol) for the common cold in adults.

    Science.gov (United States)

    Li, Siyuan; Yue, Jirong; Dong, Bi Rong; Yang, Ming; Lin, Xiufang; Wu, Taixiang

    2013-07-01

    Acetaminophen is frequently prescribed for treating patients with the common cold, but there is little evidence as to whether it is effective. To determine the efficacy and safety of acetaminophen in the treatment of the common cold in adults. We searched CENTRAL 2013, Issue 1, Ovid MEDLINE (1950 to January week 5, 2013), EMBASE (1980 to February 2013), CINAHL (1982 to February 2013) and LILACS (1985 to February 2013). We included randomised controlled trials (RCTs) comparing acetaminophen to placebo or no treatment in adults with the common cold. Studies were included if the trials used acetaminophen as one ingredient of a combination therapy. We excluded studies in which the participants had complications. Primary outcomes included subjective symptom score and duration of common cold symptoms. Secondary outcomes were overall well being, adverse events and financial costs. Two review authors independently screened studies for inclusion, assessed risk of bias and extracted data. We performed standard statistical analyses. We included four RCTs involving 758 participants. We did not pool data because of heterogeneity in study designs, outcomes and time points. The studies provided sparse information about effects longer than a few hours, as three of four included studies were short trials of only four to six hours. Participants treated with acetaminophen had significant improvements in nasal obstruction in two of the four studies. One study showed that acetaminophen was superior to placebo in decreasing rhinorrhoea severity, but was not superior for treating sneezing and coughing. Acetaminophen did not improve sore throat or malaise in two of the four studies. Results were inconsistent for some symptoms. Two studies showed that headache and achiness improved more in the acetaminophen group than in the placebo group, while one study showed no difference between the acetaminophen and placebo group. None of the included studies reported the duration of common cold

  13. Aspects of cold intrusions over Greece during autumn

    Science.gov (United States)

    Mita, Constantina; Marinaki, Aggeliki; Zeini, Konstantina; Konstantara, Metaxia

    2010-05-01

    This study is focused on the description of atmospheric disturbances that caused intense cold intrusions over Greece during autumn for a period of 25 years (1982-2006). The study was based on data analysis from the meteorological station network of the Hellenic National Meteorological Service (HNMS) and the European Centre for Medium Range Weather Forecasts (ECMWF). Initially, the days with temperature at the isobaric surface of 850 hPa less or equal to the mean temperature for the 10-day period the day under investigation belongs to are isolated, composing a new confined data set which was further used. An event of intense cold intrusion is identified based on a subjective set of criteria, considering the temperature decrease at the level of 850 hPa and its duration. In particular, the criteria that were used to identify a cold intrusion were: temperature variation between two successive days at the isobaric level of 850 hPa being equal or greater than 50 C at least once during the event and duration of the event of at least two successive days with continuous temperature decrease. Additionally, the synoptic analysis of the atmospheric disturbances involved using weather charts from ECMWF, revealed that all cases were related to low pressure systems at the level of 500 hPa, accompanied by cold air masses. Moreover, a methodology proposed to classify the cold intrusions based on general circulation characteristics of the atmosphere, resulted in seven major categories. More than half of the events belong in two categories, originated northwest of the greater Greek area (Greece and parts of neighbouring countries), between 400 and 600 N. Further analysis indicated that the frequency of events increases from September to November and the majority of the events lasted two to three days. Additionally, the non-parametric Mann-Kendall test was used for the investigation of the statistical significance of the trends appearing in the results. The tests revealed that over

  14. Scientists study 'cold war' fallout

    International Nuclear Information System (INIS)

    Stone, R.

    1993-01-01

    This article describes the epidemiological studies being carried out to determine radiation doses to the public from intentional and accidental releases of radioactive compounds during the Cold War. These studies at present are focused on Hanford, Oak Ridge, and Fernald, with studies beginning at Rocky Flats and Savannah

  15. Encyclopedia of the Cold War

    NARCIS (Netherlands)

    van Dijk, R.

    2008-01-01

    Between 1945 and 1991, tension between the USA, its allies, and a group of nations led by the USSR, dominated world politics. This period was called the Cold War - a conflict that stopped short to a full-blown war. Benefiting from the recent research of newly open archives, the Encyclopedia of the

  16. Cold gas accretion in galaxies

    NARCIS (Netherlands)

    Sancisi, Renzo; Fraternali, Filippo; Oosterloo, Tom; van der Hulst, Thijs

    Evidence for the accretion of cold gas in galaxies has been rapidly accumulating in the past years. HI observations of galaxies and their environment have brought to light new facts and phenomena which are evidence of ongoing or recent accretion: (1) A large number of galaxies are accompanied by

  17. Cold fusion and hot history

    International Nuclear Information System (INIS)

    Lewenstein, B.

    1996-01-01

    The history of cold fusion research following the announcement of the Pons-Fleischmann experiment is described in detail, including all the confusion, responses of scientists, personal impressions, personal quotations, reactions of the media, references to contemporary sources, etc. (P.A.). 5 figs

  18. Cold atoms in singular potentials

    International Nuclear Information System (INIS)

    Denschlag, J. P.

    1998-09-01

    We studied both theoretically and experimentally the interaction between cold Li atoms from a magnetic-optical trap (MOT) and a charged or current-carrying wire. With this system, we were able to realize 1/r 2 and 1/r potentials in two dimensions and to observe the motion of cold atoms in both potentials. For an atom in an attractive 1/r 2 potential, there exist no stable trajectories, instead there is a characteristic class of trajectories for which atoms fall into the singularity. We were able to observe this falling of atoms into the center of the potential. Moreover, by probing the singular 1/r 2 potential with atomic clouds of varying size and temperature we extracted scaling properties of the atom-wire interaction. For very cold atoms, and very thin wires the motion of the atoms must be treated quantum mechanically. Here we predict that the absorption cross section for the 1/r 2 potential should exhibit quantum steps. These quantum steps are a manifestation of the quantum mechanical decomposition of plane waves into partial waves. For the second part of this work, we realized a two dimensional 1/r potential for cold atoms. If the potential is attractive, the atoms can be bound and follow Kepler-like orbits around the wire. The motion in the third dimension along the wire is free. We were able to exploit this property and constructed a novel cold atom guide, the 'Kepler guide'. We also demonstrated another type of atom guide (the 'side guide'), by combining the magnetic field of the wire with a homogeneous offset magnetic field. In this case, the atoms are held in a potential 'tube' on the side of the wire. The versatility, simplicity, and scaling properties of this guide make it an interesting technique. (author)

  19. The paleoclimatic events and cause in the Okinawa Trough during 50 kaBP

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Planktonic foraminiferal d18O record for core DGKS9603 from the Okinawa Trough shows a series of climatic fluctuations and sudden cooling events in short time scale during 50 kaBP, which appear to correlate closely to the Younger Dryas and Heinrich events H1-5 recorded in Chine-se loess, the South China Sea, the North Atlantic cores and the Greenland ice cores. Three polarity reversal events, cor-relating to Gothenburg, Mungo and Laschamp events, ap-proximately correspond to Heinrich events H1, H3 and H5 respectively, which could be a cause of global climate changes. The d18O curve of the Okinawa Trough is well asso-ciated with the grain size record of the Lijiayuan loess profile in northwestern China and is somewhat different from the climate fluctuations documented in the Greenland ice cores. These correlation results indicate that regional factors play an important role in controlling the climate changes in the East Asia, and the East Asian Monsoon could be the promi-nent regional controlling factor.

  20. Cold acclimation increases cold tolerance independently of diapause programing in the bean bug, Riptortus pedestris.

    Science.gov (United States)

    Rozsypal, J; Moos, M; Goto, S G

    2017-10-17

    The bean bug (Riptortus pedestris) is a pest of soybeans and other legumes in Japan and other Asian countries. It enters a facultative adult diapause on exposure to short days. While photoperiodism and diapause are well understood in R. pedestris, knowledge of cold tolerance is very limited, as is information on the effect of diapause on cold tolerance. We examined the effect of photoperiod, cold acclimation, and feeding status on cold tolerance in R. pedestris. We found that cold acclimation significantly increased survival at -10°C in both long- and short-day adult R. pedestris. Since the difference in cold survival between long- and short-day cold-acclimated groups was only marginal, we conclude that entering diapause is not crucial for R. pedestris to successfully pass through cold acclimation and become cold tolerant. We observed similar effects in 5th instar nymphs, with both long- and short-day cold-acclimated groups surviving longer cold exposures compared with non-acclimated groups. Starvation, which was tested only in adult bugs, had only a negligible and negative impact on cold survival. Although cold tolerance significantly increased with cold acclimation in adult bugs, supercooling capacity unexpectedly decreased. Our results suggest that changes in supercooling capacity as well as in water content are unrelated to cold tolerance in R. pedestris. An analysis of metabolites revealed differences between the treatments, and while several metabolites markedly increased with cold acclimation, their concentrations were too low to have a significant effect on cold tolerance.

  1. Genetics Home Reference: familial cold autoinflammatory syndrome

    Science.gov (United States)

    ... inflammatory response. Monarch-1 is involved in the inhibition of the inflammatory response. Mutations in the NLRP12 ... cold autoinflammatory syndrome Orphanet: Familial cold urticaria Patient Support and Advocacy Resources (3 links) Autoinflammatory Alliance National ...

  2. Center for Cold Spray Research and Development

    Data.gov (United States)

    Federal Laboratory Consortium — This is the only DoD facility capable of cold spray research and development, production, and field-repair. It features three stationary cold spray systems used for...

  3. Understanding Colds: Anatomy of the Nose

    Science.gov (United States)

    ... Complications Special Features References Common Cold Understanding Colds Anatomy of the Nose The nose contains shelf-like ... white). Soft tissue, such as the eye, is gray. The maxillary sinus of adults has a volume ...

  4. Event Index - a LHCb Event Search System

    CERN Document Server

    INSPIRE-00392208; Kazeev, Nikita; Redkin, Artem

    2015-12-23

    LHC experiments generate up to $10^{12}$ events per year. This paper describes Event Index - an event search system. Event Index's primary function is quickly selecting subsets of events from a combination of conditions, such as the estimated decay channel or stripping lines output. Event Index is essentially Apache Lucene optimized for read-only indexes distributed over independent shards on independent nodes.

  5. Cold moderators for pulsed neutron sources

    International Nuclear Information System (INIS)

    Carpenter, J.M.

    1990-01-01

    This paper reviews cold moderators in pulsed neutron sources and provides details of the performance of different cold moderator materials and configurations. Analytical forms are presented which describe wavelength spectra and emission time distributions. Several types of cooling arrangements used in pulsed source moderators are described. Choices of materials are surveyed. The author examines some of the radiation damage effects in cold moderators, including the phenomenon of ''burping'' in irradiated cold solid methane. 9 refs., 15 figs., 4 tabs

  6. A transcription factor for cold sensation!

    OpenAIRE

    Kim, Susan J; Qu, Zhican; Milbrandt, Jeffrey; Zhuo, Min

    2005-01-01

    Abstract The ability to feel hot and cold is critical for animals and human beings to survive in the natural environment. Unlike other sensations, the physiology of cold sensation is mostly unknown. In the present study, we use genetically modified mice that do not express nerve growth factor-inducible B (NGFIB) to investigate the possible role of NGFIB in cold sensation. We found that genetic deletion of NGFIB selectively affected behavioral responses to cold stimuli while behavioral respons...

  7. Cold fusion anomalies more perplexing than ever

    International Nuclear Information System (INIS)

    Dagani, R.

    1989-01-01

    This article addresses the debate over research on cold fusion. Analysis is made of the research efforts that have taken place since cold fusion was first thought to have been discovered in Utah. Research in the Soviet Union on the cold fusion phenomenon is also discussed

  8. Catching a Cold When It's Warm

    Science.gov (United States)

    ... Print this issue Catching a Cold When It’s Warm What’s the Deal with Summertime Sniffles? En español ... more unfair than catching a cold when it’s warm? How can cold symptoms arise when it’s not ...

  9. Simulating events

    Energy Technology Data Exchange (ETDEWEB)

    Ferretti, C; Bruzzone, L [Techint Italimpianti, Milan (Italy)

    2000-06-01

    The Petacalco Marine terminal on the Pacific coast in the harbour of Lazaro Carclenas (Michoacan) in Mexico, provides coal to the thermoelectric power plant at Pdte Plutarco Elias Calles in the port area. The plant is being converted from oil to burn coal to generate 2100 MW of power. The article describes the layout of the terminal and equipment employed in the unloading, coal stacking, coal handling areas and the receiving area at the power plant. The contractor Techint Italimpianti has developed a software system, MHATIS, for marine terminal management which is nearly complete. The discrete event simulator with its graphic interface provides a real-type decision support system for simulating changes to the terminal operations and evaluating impacts. The article describes how MHATIS is used. 7 figs.

  10. Event generators

    International Nuclear Information System (INIS)

    Durand, D.; Gulminelli, F.; Lopez, O.; Vient, E.

    1998-01-01

    The results concerning the heavy ion collision simulations at Fermi energies by means of phenomenological models obtained in the last two years ar presented. The event generators are essentially following the phase of elaboration of analysis methods of data obtained by INDRA or NAUTILUS 4 π multidetectors. To identify and correctly quantify a phenomenon or a physical quantity it is necessary to verify by simulation the feasibility and validity of the analysis and also to estimate the bias introduced by the experimental filter. Many studies have shown this, for instance: the determination of the collision reaction plan for flow studies, determination of kinematical characteristics of the quasi-projectiles, and the excitation energy measurement stored in the hot nuclei. To Eugene, the currently utilised generator, several improvements were added: introduction of space-time correlations between the different products emitted in the decay of excited nuclei by calculating the trajectories of the particles in the final phase of the reaction; taking into account in the decay cascade of the discrete levels of the lighter fragments; the possibility of the schematically description of the explosion of the nucleus by simultaneous emission of multi-fragments. Thus, by comparing the calculations with the data relative to heavy systems studied with the NAUTILUS assembly it was possible to extract the time scales in the nuclear fragmentation. The utilisation of these event generators was extended to the analysis of INDRA data concerning the determination of the vaporization threshold in the collisions Ar + Ni and also the research of the expansion effects in the collisions Xe + Sn at 50 MeV/u

  11. Are cold winters in Europe associated with low solar activity?

    International Nuclear Information System (INIS)

    Lockwood, M; Harrison, R G; Woollings, T; Solanki, S K

    2010-01-01

    Solar activity during the current sunspot minimum has fallen to levels unknown since the start of the 20th century. The Maunder minimum (about 1650-1700) was a prolonged episode of low solar activity which coincided with more severe winters in the United Kingdom and continental Europe. Motivated by recent relatively cold winters in the UK, we investigate the possible connection with solar activity. We identify regionally anomalous cold winters by detrending the Central England temperature (CET) record using reconstructions of the northern hemisphere mean temperature. We show that cold winter excursions from the hemispheric trend occur more commonly in the UK during low solar activity, consistent with the solar influence on the occurrence of persistent blocking events in the eastern Atlantic. We stress that this is a regional and seasonal effect relating to European winters and not a global effect. Average solar activity has declined rapidly since 1985 and cosmogenic isotopes suggest an 8% chance of a return to Maunder minimum conditions within the next 50 years (Lockwood 2010 Proc. R. Soc. A 466 303-29): the results presented here indicate that, despite hemispheric warming, the UK and Europe could experience more cold winters than during recent decades.

  12. Cold Stowage: An ISS Project

    Science.gov (United States)

    Hartley, Garen

    2018-01-01

    NASA's vision for humans pursuing deep space flight involves the collection of science in low earth orbit aboard the International Space Station (ISS). As a service to the science community, Johnson Space Center (JSC) has developed hardware and processes to preserve collected science on the ISS and transfer it safely back to the Principal Investigators. This hardware includes an array of freezers, refrigerators, and incubators. The Cold Stowage team is part of the International Space Station (ISS) program. JSC manages the operation, support and integration tasks provided by Jacobs Technology and the University of Alabama Birmingham (UAB). Cold Stowage provides controlled environments to meet temperature requirements during ascent, on-orbit operations and return, in relation to International Space Station Payload Science.

  13. Ultra-cold molecule production

    International Nuclear Information System (INIS)

    Ramirez-Serrano, Jamie; Chandler, David W.; Strecker, Kevin; Rahn, Larry A.

    2005-01-01

    The production of Ultra-cold molecules is a goal of many laboratories through out the world. Here we are pursuing a unique technique that utilizes the kinematics of atomic and molecular collisions to achieve the goal of producing substantial numbers of sub Kelvin molecules confined in a trap. Here a trap is defined as an apparatus that spatially localizes, in a known location in the laboratory, a sample of molecules whose temperature is below one degree absolute Kelvin. Further, the storage time for the molecules must be sufficient to measure and possibly further cool the molecules. We utilize a technique unique to Sandia to form cold molecules from near mass degenerate collisions between atoms and molecules. This report describes the progress we have made using this novel technique and the further progress towards trapping molecules we have cooled

  14. Cosmicflows-3: Cold Spot Repeller?

    Energy Technology Data Exchange (ETDEWEB)

    Courtois, Hélène M.; Graziani, Romain; Dupuy, Alexandra [University of Lyon, UCB Lyon 1, CNRS/IN2P3, IPN, Lyon (France); Tully, R. Brent [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); Hoffman, Yehuda [Racah Institute of Physics, Hebrew University, Jerusalem, 91904 (Israel); Pomarède, Daniel [Institut de Recherche sur les Lois Fondamentales de l’Univers, CEA, Université Paris-Saclay, F-91191 Gif-sur-Yvette (France)

    2017-09-20

    The three-dimensional gravitational velocity field within z ∼ 0.1 has been modeled with the Wiener filter methodology applied to the Cosmicflows-3 compilation of galaxy distances. The dominant features are a basin of attraction and two basins of repulsion. The major basin of attraction is an extension of the Shapley concentration of galaxies. One basin of repulsion, the Dipole Repeller, is located near the anti-apex of the cosmic microwave background dipole. The other basin of repulsion is in the proximate direction toward the “Cold Spot” irregularity in the cosmic microwave background. It has been speculated that a vast void might contribute to the amplitude of the Cold Spot from the integrated Sachs–Wolfe effect.

  15. Late Pleistocene Climate Events and The Origin of Agriculture In SW Asia

    Science.gov (United States)

    Rossignol-Strick, M.

    In the Eastern Mediterranean sea, the climate succession of the last deglaciation is documented and dated in marine cores by the d18-O variation of foraminiferal cal- cite and pollen records. The Last Glacial Maximum is identified by a large abundance of grass pollen from a prairie-type vegetal cover with low annual precipitation in the mountainous north and east borderlands of the sea, where the pollen mainly origi- nates. During the first phase of the last deglaciation, the Bolling/Allerod chronozone, the moisture availability increases and makes possible the spread of a deciduous for- est, as shown by the increasing pollen abundance of the deciduous oak. The cold and arid Younger Dryas is identified by a reversal to semi-desert conditions, with the in- crease of sage-brush (Artemisia) and the saline-tolerant Chenopodiaceae. The climate of the earliest Holocene is Optimum for at least 3000 years (9000-6000yr BP), with the largest spread of the deciduous forest at low-middle elevations signalling wet sum- mers and of the Pistacia woodland at low elevations signalling mild, no-frost winters. This is the time when the most recent sapropel deposited in the eastern Mediterranean under anoxic bottom conditions generated by a surface lid of lower salinity due to the concomitant largest floods of the Nile River fed by the strongest African monsoon rains in the Ethiopian Highlands. In SW Asia, the pollen records of lakes and marshes have been correlated with those of the marine cores, thereby obtaining a robust time-frame. In that area, the archaeo- logical data of human settlements are independently dated by 14C. Thus the archaeo- logical succession can be securely set against the well-dated climatic succession. The Late Palaeolithic populations of SW Asia were wandering hunter-gatherers in the prairies of the Last Glacial Maximum, where they already collected wild wheat, barley and fruit. With the Bolling/Allerod wetter and warmer climate, they began to settle in

  16. The status of 'cold fusion'

    International Nuclear Information System (INIS)

    Nagel, David J.

    1998-01-01

    The questions raised by reports of nuclear reactions at low energies, so called 'cold fusion', are not yet answered to the satisfaction of many scientists. Further experimental investigations of these and related questions seems desirable, at least for scientific if not practical reasons. Properly conducted, such investigations would be indistinguishable from normal research. They would yield information germane to accepted areas of scientific inquiry and technological utility

  17. Events diary

    Science.gov (United States)

    2000-01-01

    as Imperial College, the Royal Albert Hall, the Royal College of Art, the Natural History and Science Museums and the Royal Geographical Society. Under the heading `Shaping the future together' BA2000 will explore science, engineering and technology in their wider cultural context. Further information about this event on 6 - 12 September may be obtained from Sandra Koura, BA2000 Festival Manager, British Association for the Advancement of Science, 23 Savile Row, London W1X 2NB (tel: 0171 973 3075, e-mail: sandra.koura@britassoc.org.uk ). Details of the creating SPARKS events may be obtained from creating.sparks@britassoc.org.uk or from the website www.britassoc.org.uk . Other events 3 - 7 July, Porto Alegre, Brazil VII Interamerican conference on physics education: The preparation of physicists and physics teachers in contemporary society. Info: IACPE7@if.ufrgs.br or cabbat1.cnea.gov.ar/iacpe/iacpei.htm 27 August - 1 September, Barcelona, Spain GIREP conference: Physics teacher education beyond 2000. Info: www.blues.uab.es/phyteb/index.html

  18. Geophysical events

    Science.gov (United States)

    This is a summary of SEAN Bulletin, 13(3), March 31, 1988, a publication of the Smithsonian Institution's Scientific Event Alert Network. The complete bulletin is available in the microfiche edition of Eos as a microfiche supplement or as a paper reprint. For the microfiche, order document E88-002 at $2.50 (U.S.) by writing to AGU Orders, 2000 Florida Avenue, N.W., Washington, DC 20009 or by calling toll free on 800-424-2488. For the paper reprint, order SEAN Bulletin (giving volume and issue numbers and issue date) through the same address; the price is $3.50 for one copy of each issue number for those who do not have a deposit account, $2 for those who do; additional copies of each issue number are $1. Subscriptions to SEAN Bulletin are also available from AGU-Orders; the price is $18 for 12 monthly issues mailed to a U.S. address, $28 if mailed elsewhere, and must be prepaid.

  19. Cold episodes in the Peruvian Central Andes: Composites, Types, and their Impacts over South America (1958-2014)

    Science.gov (United States)

    Sulca, J. C.; Vuille, M. F.; Roundy, P. E.; Trasmonte, G.; Silva, Y.; Takahashi, K.

    2015-12-01

    The Mantaro basin (MB) is located in the central Peruvian Andes. Occasionally, cold episodes are observed during austral summer (January-March), that strongly damage crops. However, little is known about the causes and impacts of such cold episodes. The main goal of this study is thus to characterize cold episodes in the MB and assess their large-scale circulation and teleconnections over South America (SA) during austral summer. To identify cold events in the MB daily minimum temperature (Tmin) for the period 1958-2014 from Huayao station, located within the MB was used. A cold episode is defined when daily minimum temperature drops below its 10-percentile for at least one day. Additionally, to study the sensitivity between physical mechanisms associated with cold episodes and temperature, cold episodes are classified in three groups: Weak cold episodes (7.5 ≤ Tmin ≤ 10 percentile), strong cold episodes (Tmin ≤ 2.5 percentile), but excluding the 9 coldest events (Tmin ≤ 0 ͦ C), henceforth referred to as extraordinary cold episodes. Several gridded reanalysis were used to characterize the large-scale circulation, cloud cover and rainfall over SA associated with these events. Weak and strong cold episodes in the MB are mainly associated with a weakening of the Bolivian High-Nordeste Low system by tropical-extratropical interactions. Both types of cold episodes are associated with westerly wind anomalies at mid- and upper-tropospheric levels aloft the Peruvian Central Andes, which inhibit the influx of humid air masses from the lowlands to the east and hence limit the development of cloud cover (e.g., positive OLR anomalies over MB). The resulting clear sky conditions cause nighttime temperatures to drop, leading to cold extremes below 10-percentile. Simultaneously, northeastern Brazil (NEB) registers negative OLR anomalies, strong convection and enhanced cloud cover because displacement of the South Atlantic Convergence Zone (SACZ) toward the northeast of

  20. The Cold man. A clinical case of the cold sensation.

    Directory of Open Access Journals (Sweden)

    Salvatore Settineri

    2013-09-01

    Full Text Available The lack of correlation between available knowledge and the current approach to Somatoform Disorders is highlighted.. Methods: the study, via the analysis of an unusual clinical case of an anomalous sensation of cold, examines various hypotheses on the physiopathology of somatization. Conclusions: a conceptualization would focus attention on the level of patients’ preoccupation with their symptoms, on the anomalies of the variations of perceptions and on patients’ hyperarousal. It could lead to a more harmonious position in psychiatry, between anthropologically-based understanding and interpretation of psychophysical information.

  1. Cold Fusion Has Now Come Out of the Cold

    Science.gov (United States)

    Storms, Edmund

    2003-10-01

    The phenomenon called cold fusion or LENR (Low-Energy-Nuclear-Reaction) has now achieved a level of reproducibility and understanding that warrants re-examination of the claims. A summary of what is known and want is being done worldwide to obtain more knowledge will be given. Rather than disappearing as better data are obtained, the effects are becoming more reproducible and of greater magnitude. Justification for this claim can be obtained at www.LENR-CANR.org. The phenomenon is too important to ignore any longer even though it conflicts with conventional theory.

  2. Cold atoms close to surfaces

    DEFF Research Database (Denmark)

    Krüger, Peter; Wildermuth, Stephan; Hofferberth, Sebastian

    2005-01-01

    Microscopic atom optical devices integrated on atom chips allow to precisely control and manipulate ultra-cold (T atoms and Bose-Einstein condensates (BECs) close to surfaces. The relevant energy scale of a BEC is extremely small (down to ... be utilized as a sensor for variations of the potential energy of the atoms close to the surface. Here we describe how to use trapped atoms as a measurement device and analyze the performance and flexibility of the field sensor. We demonstrate microscopic magnetic imaging with simultaneous high spatial...

  3. Is cold or warm blood cardioplegia superior for myocardial protection?

    Science.gov (United States)

    Abah, Udo; Roberts, Patrick Garfjeld; Ishaq, Muhammad; De Silva, Ravi

    2012-01-01

    A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether the use of warm or cold blood cardioplegia has superior myocardial protection. More than 192 papers were found using the reported search, of which 20 represented the best evidence to answer the clinical question. The authors, journal, date, country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. A good breadth of high-level evidence addressing this clinical dilemma is available, including a recent meta-analysis and multiple large randomized clinical trials. Yet despite this level of evidence, no clear significant clinical benefit has been demonstrated by warm or cold blood cardioplegia. This suggests that neither method is significantly superior and that both provide similar efficacy of myocardial protection. The meta-analysis, including 41 randomized control trials (5879 patients in total), concluded that although a lower cardiac enzyme release and improved postoperative cardiac index was demonstrated in the warm cardioplegia group, this benefit was not reflected in clinical outcomes, which were similar in both groups. This theme of benefit in biochemical markers, physiological metrics and non-fatal postoperative events in the warm cardioplegia group ran throughout the literature, in particular the ‘Warm Heart investigators’ who conducted a randomized trial of 1732 patients, demonstrated a reduction in postoperative low output syndrome (6.1 versus 9.3%, P = 0.01) in the warm cardioplegia group, but no significant drop in 30-day all-cause mortality (1.4 versus 2.5%, P = 0.12). However, their later follow-up indicates non-fatal postoperative events predict reduced late survival, independent of cardioplegia. A minority of studies suggested a benefit of cold cardioplegia over warm in particular patient subgroups: One group conducted a retrospective study of 520 patients who

  4. International workshop on cold neutron sources

    International Nuclear Information System (INIS)

    Russell, G.J.; West, C.D.

    1991-08-01

    The first meeting devoted to cold neutron sources was held at the Los Alamos National Laboratory on March 5--8, 1990. Cosponsored by Los Alamos and Oak Ridge National Laboratories, the meeting was organized as an International Workshop on Cold Neutron Sources and brought together experts in the field of cold-neutron-source design for reactors and spallation sources. Eighty-four people from seven countries attended. Because the meeting was the first of its kind in over forty years, much time was spent acquainting participants with past and planned activities at reactor and spallation facilities worldwide. As a result, the meeting had more of a conference flavor than one of a workshop. The general topics covered at the workshop included: Criteria for cold source design; neutronic predictions and performance; energy deposition and removal; engineering design, fabrication, and operation; material properties; radiation damage; instrumentation; safety; existing cold sources; and future cold sources

  5. International workshop on cold neutron sources

    Energy Technology Data Exchange (ETDEWEB)

    Russell, G.J.; West, C.D. (comps.) (Los Alamos National Lab., NM (United States))

    1991-08-01

    The first meeting devoted to cold neutron sources was held at the Los Alamos National Laboratory on March 5--8, 1990. Cosponsored by Los Alamos and Oak Ridge National Laboratories, the meeting was organized as an International Workshop on Cold Neutron Sources and brought together experts in the field of cold-neutron-source design for reactors and spallation sources. Eighty-four people from seven countries attended. Because the meeting was the first of its kind in over forty years, much time was spent acquainting participants with past and planned activities at reactor and spallation facilities worldwide. As a result, the meeting had more of a conference flavor than one of a workshop. The general topics covered at the workshop included: Criteria for cold source design; neutronic predictions and performance; energy deposition and removal; engineering design, fabrication, and operation; material properties; radiation damage; instrumentation; safety; existing cold sources; and future cold sources.

  6. A transcription factor for cold sensation!

    Directory of Open Access Journals (Sweden)

    Milbrandt Jeffrey

    2005-03-01

    Full Text Available Abstract The ability to feel hot and cold is critical for animals and human beings to survive in the natural environment. Unlike other sensations, the physiology of cold sensation is mostly unknown. In the present study, we use genetically modified mice that do not express nerve growth factor-inducible B (NGFIB to investigate the possible role of NGFIB in cold sensation. We found that genetic deletion of NGFIB selectively affected behavioral responses to cold stimuli while behavioral responses to noxious heat or mechanical stimuli were normal. Furthermore, behavioral responses remained reduced or blocked in NGFIB knockout mice even after repetitive application of cold stimuli. Our results provide strong evidence that the first transcription factor NGFIB determines the ability of animals to respond to cold stimulation.

  7. Cold trap disposed within a tank

    International Nuclear Information System (INIS)

    Kanbe, Mitsuru.

    1983-01-01

    Purpose: To improve the reliability and the durability of cold traps by simplifying the structure and recycling liquid metals without using electromagnetic pumps. Constitution: The reactor container is partitioned by an intermediate container enhousing primary recycling pumps and cold traps. The inlet and the exit for the liquid metal of each cold trap are opened to the outside and the inside of the intermediate container respectively. In such a structure, the pressure difference between the inside and the outside of the intermediate container is exerted on the cold traps due to the exhaust pressure of the recycling pumps in which the liquid metal flowing into the cold traps is purified through filters, cooled and then discharged from the exit to the cold plenum. In this way, liquid metal can be recycled without using an electromagnetic pump whose reliability has not yet been established. (Kamimura, M.)

  8. Taming light with cold atoms

    International Nuclear Information System (INIS)

    Vestergaard Hau, Lene

    2002-01-01

    Much of the extraordinary progress of developments in communication (e-mail, and/or internet) has been achieved due to improvements in optical communication. This paper describes a new approach which could improve the speed of communication. The ability to stop light in its tracks by passing it through a cloud of ultracold atoms could lead to new techniques for optical storage. The described slow-light experiments have triggered new physics both on the experimental and theoretical fronts. The cold atom system allows the steepest possible refractive index profiles, and therefore the most dramatic effects, as Doppler effects are eliminated. Furthermore, cold atoms provide maximum flexibility in the choice of beam geometry. This is important for the storage and retrieval of multiple pulses of optical information in an atomic medium, as it would allow individual pulses to be selectively addressed. Slow and stopped light have many potential applications in optical communication and processing, including optical information storage, ultra-sensitive optical switches, and optical delay lines. It could also be used in quantum-information processing, in which quantum-mechanical information is used for computing and communication purposes. On a very different front, slow light provides us with a totally new way of probing the unusual properties of Bose-Einstein condensates

  9. Experiments with cold hydrogen atoms

    International Nuclear Information System (INIS)

    Leonas, V.B.

    1981-01-01

    Numerous investigations of atomic processes in Waseous phase on the surface with participation of ''cold'' hydrogen atoms, made during the last years, are considered. The term ''cold atom'' means the range of relative collision energies E<10 MeV (respectively 'ultracold ' atoms at E< or approximately 1 MeV) which corresponds to the range of temperatures in tens (units) of K degrees. Three main ranges of investigations where extensive experimental programs are realized are considered: study of collisional processes with hydrogen atom participation, hydrogen atoms being of astrophysical interest; study of elastic atom-molecular scattering at superlow energies and studies on the problem of condensed hydrogen. Hydrogen atoms production is realized at dissociation in non-electrode high-frequency or superhigh-frequency discharge. A method of hydrogen quantum generator and of its modifications appeared to be rather an effective means to study collisional changes of spin state of hydrogen atoms. First important results on storage and stabilization of the gas of polarized hydrogen atoms are received

  10. Current status of cold fusion

    International Nuclear Information System (INIS)

    Tsarev, V.A.

    1992-01-01

    This paper reports that the term cold fusion (CF) was known up to March 1989 as the synonym of muon-catalyzed fusion, suggested by A.D. Sakharov more than 40 years ago. Broad use of this term for the last two years is associated with other kind of phenomena: fusion at ambient room temperature of nuclei of hydrogen isotopes embedded into crystal lattice. Nowadays only few remember the unbelievable resonance in the whole world, caused by the first claims of CF from Utah and associated with hopes of a simple and ecologically safe solution to the energy problems confronting humanity. The range of the interest reflected also the receptivity of our society for scientific ideas and wide development of telecommunication media. Extraordinary simplicity of CF experiments (in sharp contrast with hug complexity and high cost of thermonuclear researches) stimulated fast involvement of a large number of specialists of various profiles. Participation of small groups and even individual enthusiasts disposing of only simplest physical and chemical equipment became possible. Figuratively speaking, everybody with a pair of strong hands and a spade had a chance to find his nugget of gold in this Klondike. As a result: passion, rush and a very nonuniform composition of participants in this race for cold fusion, far from being all property prepared and having sense of responsibility

  11. Context-dependent effects of cold stress on behavioral, physiological, and life-history traits of the red flour beetle.

    Science.gov (United States)

    Scharf, Inon; Wertheimer, Keren-Or; Xin, Joy Lim; Gilad, Tomer; Goldenberg, Inna; Subach, Aziz

    2017-06-20

    Animals are exposed in nature to a variety of stressors. While stress is generally harmful, mild stress can also be beneficial and contribute to reproduction and survival. We studied the effect of five cold shock events versus a single cold shock and a control group, representing three levels of stress (harsh, mild, and no stress), on behavioral, physiological, and life-history traits of the red flour beetle (Tribolium castaneum, Herbst 1797). Beetles exposed to harsh cold stress were less active than a control group: they moved less and failed more frequently to detect a food patch. Their probability to mate was also lower. Beetle pairs exposed to harsh cold stress frequently failed to reproduce at all, and if reproducing, females laid fewer eggs, which were, as larvae in mid-development, smaller than those in the control group. However, harsh cold stress led to improved female starvation tolerance, probably due to enhanced lipid accumulation. Harsh cold shock also improved tolerance to an additional cold shock compared to the control. Finally, a single cold shock event negatively affected fewer measured response variables than the harsh cold stress, but also enhanced neither starvation tolerance nor tolerance to an additional cold shock. The consequences of a harsher cold stress are thus not solely detrimental but might even enhance survival under stressful conditions. Under benign conditions, nevertheless, harsh stress impedes beetle performance. The harsh stress probably shifted the balance point of the survival-reproduction trade-off, a shift that did not take place following exposure to mild stress. © 2017 Institute of Zoology, Chinese Academy of Sciences.

  12. On the dynamics of an extreme rainfall event in northern India in 2013

    Indian Academy of Sciences (India)

    Anu Xavier

    2018-03-08

    Mar 8, 2018 ... the cold air to move southward. During the event, as the cold air moved south, it pushed the mid-latitude westerlies south of its normal position during summer monsoon and created a ... gradient between southern Asia and the Indian. Ocean develops due to increased solar heating over the Indian land area ...

  13. Cold dark matter from the hidden sector

    International Nuclear Information System (INIS)

    Arias, Paola; Pontificia Univ. Catolica de Chile, Santiago

    2012-02-01

    Weakly interacting slim particles (WISPs) such as hidden photons (HP) and axion-like particles (ALPs) have been proposed as cold dark matter candidates. They might be produced non-thermally via the misalignment mechanism, similarly to cold axions. In this talk we review the main processes of thermalisation of HP and we compute the parameter space that may survive as cold dark matter population until today. Our findings are quite encouraging for experimental searches in the laboratory in the near future.

  14. Cold dark matter from the hidden sector

    Energy Technology Data Exchange (ETDEWEB)

    Arias, Paola [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Pontificia Univ. Catolica de Chile, Santiago (Chile). Facultad de Fisica

    2012-02-15

    Weakly interacting slim particles (WISPs) such as hidden photons (HP) and axion-like particles (ALPs) have been proposed as cold dark matter candidates. They might be produced non-thermally via the misalignment mechanism, similarly to cold axions. In this talk we review the main processes of thermalisation of HP and we compute the parameter space that may survive as cold dark matter population until today. Our findings are quite encouraging for experimental searches in the laboratory in the near future.

  15. Observation of stars produced during cold fusion

    International Nuclear Information System (INIS)

    Matsumoto, T.

    1992-01-01

    It has been indicated tht multiple-neutron nuclei such as quad-neutrons can be emitted during cold fusion. These multiple-neutrons might bombard the nuclei of materials outside a cold fusion cell to cause nuclear reactions. In this paper, observations of nuclear emulsions that were irradiated during a cold fusion experiment with heavy water and palladium foil are described. Various traces, like stars, showing nuclear reactions caused by the multiple-neutrons have been clearly observed

  16. Prediction of cold flow properties of Biodiesel

    Directory of Open Access Journals (Sweden)

    Parag Saxena

    2016-08-01

    Full Text Available Biodiesel being environmentally friendly is fast gaining acceptance in the market as an alternate diesel fuel. But compared to petroleum diesel it has certain limitations and thus it requires further development on economic viability and improvement in its properties to use it as a commercial fuel. The cold flow properties play a major role in the usage of biodiesel commercially as it freezes at cold climatic conditions. In the present study, cold flow properties of various types of biodiesel were estimated by using correlations available in literature. The correlations were evaluated based on the deviation between the predicted value and experimental values of cold flow properties.

  17. Evaporative cooling enhanced cold storage system

    Science.gov (United States)

    Carr, P.

    1991-10-15

    The invention provides an evaporatively enhanced cold storage system wherein a warm air stream is cooled and the cooled air stream is thereafter passed into contact with a cold storage unit. Moisture is added to the cooled air stream prior to or during contact of the cooled air stream with the cold storage unit to effect enhanced cooling of the cold storage unit due to evaporation of all or a portion of the added moisture. Preferably at least a portion of the added moisture comprises water condensed during the cooling of the warm air stream. 3 figures.

  18. Cold vacuum drying facility design requirements

    International Nuclear Information System (INIS)

    IRWIN, J.J.

    1999-01-01

    This document provides the detailed design requirements for the Spent Nuclear Fuel Project Cold Vacuum Drying Facility. Process, safety, and quality assurance requirements and interfaces are specified

  19. Review on Cold-Formed Steel Connections

    Science.gov (United States)

    Tan, Cher Siang; Mohammad, Shahrin; Md Tahir, Mahmood; Shek, Poi Ngian

    2014-01-01

    The concept of cold-formed light steel framing construction has been widespread after understanding its structural characteristics with massive research works over the years. Connection serves as one of the important elements for light steel framing in order to achieve its structural stability. Compared to hot-rolled steel sections, cold-formed steel connections perform dissimilarity due to the thin-walled behaviour. This paper aims to review current researches on cold-formed steel connections, particularly for screw connections, storage rack connections, welded connections, and bolted connections. The performance of these connections in the design of cold-formed steel structures is discussed. PMID:24688448

  20. Cold neutron radiography using low power accelerator

    International Nuclear Information System (INIS)

    Kiyanagi, Yoshiaki; Iwasa, Hirokatu

    1993-01-01

    A cold neutron source which can be adopted at a low power accelerator was studied. Time-of-flight radiography using the cold neutron source was performed. It is suggested that time-of-flight cold neutron radiography has possibility to distinguish the materials more clearly than the traditional film method since large contrast differences can be obtained by using digital data of the neutron intensity at different energies from thermal to cold region. Material will be identified at the same time by this method. (author)

  1. Cold vacuum drying facility design requirements

    Energy Technology Data Exchange (ETDEWEB)

    IRWIN, J.J.

    1999-07-01

    This document provides the detailed design requirements for the Spent Nuclear Fuel Project Cold Vacuum Drying Facility. Process, safety, and quality assurance requirements and interfaces are specified.

  2. Heat and cold accumulators in vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Kauranen, P.; Wikstroem, L. (VTT Technical Research Centre of Finland, Advanced Materials, Tampere (Finland)); Heikkinen, J. (VTT Technical Research Centre of Finland, Building Services and Indoor Environment, Espoo (Finland)); Laurikko, J.; Elonen, T. (VTT Technical Research Centre of Finland, Emission Control, Espoo (Finland)); Seppaelae, A. (Helsinki Univ. of Technology, Applied Thermodynamics, Espoo (Finland)). Email: ari.seppala@tkk.fi

    2009-07-01

    Phase Change Material (PCM) based heat and cold accumulators have been tailored for transport applications including a mail delivery van as well as the cold chains of foodstuff and blood products. The PCMs can store relative large amount of thermal energy in a narrow temperature interval as latent heat of fusion of their melting and crystallization processes. Compact heat and cold accumulators can be designed using PCMs. The aim of the project has been to reduce the exhaust gas and noise emissions and improve the fuel economy of the transport systems and to improve the reliability of the cold chains studied by storing thermal energy in PCM accumulators. (orig.)

  3. Superpower nuclear minimalism in the post-Cold War era?

    International Nuclear Information System (INIS)

    Graben, E.K.

    1992-07-01

    With the end of the Cold War and the breakup of the Soviet Union, the strategic environment has fundamentally changed, so it would seem logical to reexamine strategy as well. There are two main schools of nuclear strategic thought: a maximalist school, which emphasizes counterforce superiority and nuclear war-fighting capability, and a MAD-plus school, which emphasizes survivability of an assured destruction capability along with the ability to deliver small, limited nuclear attacks in the event that conflict occurs. The MAD-plus strategy is the more logical of the two strategies, because the maximalist strategy is based on an attempt to conventionalize nuclear weapons which is unrealistic

  4. IMPROVED, FAVORABLE FOR ENVIRONMENT POLYURETHANE COLD-BOX-PROCESS (COLD BOX «HUTTENES-ALBERTUS» .

    Directory of Open Access Journals (Sweden)

    A. Sergini

    2005-01-01

    Full Text Available The results of the laboratory and industrial investigations, the purpose of which is improvement of the classical Cold-box-process, i.e. the process of the slugs hardening in cold boxes, are presented.

  5. Vaccine Adverse Events

    Science.gov (United States)

    ... for Biologics Evaluation & Research Vaccine Adverse Events Vaccine Adverse Events Share Tweet Linkedin Pin it More sharing ... in the primary immunization series in infants Report Adverse Event Report a Vaccine Adverse Event Contact FDA ( ...

  6. The detection of cold antihydrogen atoms

    International Nuclear Information System (INIS)

    Zhang, Zhongdong

    2007-01-01

    The ATRAP experiment at CERN's antiproton decelerator (AD) aims for a test of CPT violation and Lorentz invariance by a comparison of hydrogen to antihydrogen atom spectroscopy and a measurement of the gravitational force on antimatter atoms. The experiment is divided into two parts: ATRAP-I, where successfully antihydrogen atoms were produced and intensive studies on the charged clouds of positrons and antiprotons were performed, and ATRAP-II which was commissioned during the beam-time 2006. ATRAP-II includes a much larger superconducting solenoid bore allowing the installation of an extended detection system as well as an optimized combined Penning-Ioffe trap. Another essential part is a new positron accumulator and delivery system which will increase the ATRAP-II efficiency drastically. Thus ATRAP-II now allows for much larger flexibility, increased performance, higher robustness, and better efficiency for the production and storage of cold antihydrogen atoms. A general overview of the experimental setup for the second phase of the ATRAP experiment will be presented in this thesis. The antiproton annihilation detector system, consisting of several layers of scintillating fibers, counts the antihydrogen atoms and determines the annihilation vertex of the atoms. This diagnostic element will allow to optimize the production of cold antihydrogen sufficiently to permit optical observations and measurements. Extensive Monte Carlo simulations concerning the track fitting and vertex reconstruction have been developed during the planned interruption of antiproton production at AD in the year 2005. Different event generators, magnetic field distributions as well as data reconstruction algorithms on simulated data were established and the results were compared to data in 2006. To improve the detector position resolution, a constraint-fit procedure was adopted. Further possible improvements, by applying certain cuts on the data, were investigated. Real-time measurements

  7. Surge recovery techniques for the Tevatron cold compressors

    International Nuclear Information System (INIS)

    Martinez, A.; Klebaner, A.L.; Makara, J.N.; Theilacker, J.C.; Fermilab

    2006-01-01

    The Fermilab Tevatron cryogenic system utilizes high-speed centrifugal cold compressors, made by Ishikawajima-Harima Heavy Industries Co. Ltd. (IHI), for high-energy operations [1]. The compressor is designed to pump 60 g/s of 3.6 K saturated helium vapor at a pressure ratio of 2.8, with an off-design range of 40 to 70 g/s and operating speeds between 40 and 95 krpm. Since initial commissioning in 1993, Tevatron transient conditions such as quench recovery have led to multiple-location machine trips as a result of the cold compressors entering the surge regime. Historically, compressors operating at lower inlet pressures and higher speeds have been especially susceptible to these machine trips and it was not uncommon to have multiple compressor trips during large multiple-house quenches. In order to cope with these events and limit accelerator down time, surge recovery techniques have been implemented in an attempt to prevent the compressors from tripping once the machine entered this surge regime. This paper discusses the different methods of surge recovery that have been employed. Data from tests performed at the Cryogenic Test Facility at Fermilab as well as actual Tevatron operational data were utilized. In order to aid in the determination of the surge region, a full mapping study was undertaken to characterize the entire pressure field of the cold compressor. These techniques were then implemented and tested at several locations in the Tevatron with some success

  8. On cold spots in tumor subvolumes

    International Nuclear Information System (INIS)

    Tome, Wolfgang A.; Fowler, Jack F.

    2002-01-01

    Losses in tumor control are estimated for cold spots of various 'sizes' and degrees of 'cold dose'. This question is important in the context of intensity modulated radiotherapy where differential dose-volume histograms (DVHs) for targets that abut a critical structure often exhibit a cold dose tail. This can be detrimental to tumor control probability (TCP) for fractions of cold volumes even as small as 1%, if the cold dose is lower than the prescribed dose by substantially more than 10%. The Niemierko-Goitein linear-quadratic algorithm with γ 50 slope 1-3 was used to study the effect of cold spots of various degrees (dose deficit below the prescription dose) and size (fractional volume of the cold dose). A two-bin model DVH has been constructed in which the cold dose bin is allowed to vary from a dose deficit of 1%-50% below prescription dose and to have volumes varying from 1% to 90%. In order to study and quantify the effect of a small volume of cold dose on TCP and effective uniform dose (EUD), a four-bin DVH model has been constructed in which the lowest dose bin, which has a fractional volume of 1%, is allowed to vary from 10% to 45% dose deficit below prescription dose. The highest dose bin represents a simultaneous boost. For fixed size of the cold spot the calculated values of TCP decreased rapidly with increasing degrees of cold dose for any size of the cold spot, even as small as 1% fractional volume. For the four-subvolume model, in which the highest dose bin has a fractional volume of 80% and is set at a boost dose of 10% above prescription dose, it is found that the loss in TCP and EUD is moderate as long as the cold 1% subvolume has a deficit less than approximately 20%. However, as the dose deficit in the 1% subvolume bin increases further it drives TCP and EUD rapidly down and can lead to a serious loss in TCP and EUD. Since a dose deficit to a 1% volume of the target that is larger than 20% of the prescription dose may lead to serious loss of

  9. Age and Ethnic Differences in Cold Weather and Contagion Theories of Colds and Flu

    Science.gov (United States)

    Sigelman, Carol K.

    2012-01-01

    Age and ethnic group differences in cold weather and contagion or germ theories of infectious disease were explored in two studies. A cold weather theory was frequently invoked to explain colds and to a lesser extent flu but became less prominent with age as children gained command of a germ theory of disease. Explanations of how contact with…

  10. Cuba and Economic Sanctions: A Cold War Strategy in the 21st Century

    National Research Council Canada - National Science Library

    Kelley, Thomas

    2004-01-01

    .... These sanctions and U.S. attitudes and perceptions were based on objectives driven by the Cold War and as such are outdated and overtaken by events. The sanctions should be lifted and diplomatic ties once again established both to support United States goals in the region and for quality of life improvements for Cuba.

  11. Improved Windows for Cold Climates

    DEFF Research Database (Denmark)

    Laustsen, Jacob Birck; Svendsen, Svend

    2005-01-01

    considerably by reducing the frame width, which results in a larger transparent area causing a larger solar gain but still main-taining a low thermal transmittance. Using three layers of glass with large gaps, using very slim frame profiles, and omitting the edge constructions that normally causes thermal...... windows with improved energy performance. Traditionally evaluation of the energy performance of windows has focused on the thermal transmittance, but as windows differ from the rest of the building envelope by allowing solar energy to enter the building, the total solar energy transmittance is equally...... important. In the heating season in cold climates the solar gain through windows can be utilized for space heating which results in a corresponding reduction in the energy production that is often based on fossil fuels. A suitable quantity for evaluating the energy performance of windows in a simple...

  12. Does cold nuclear fusion exist?

    International Nuclear Information System (INIS)

    Brudanin, V.B.; Bystritskij, V.M.; Egorov, V.G.; Shamsutdinov, S.G.; Shyshkin, A.L.; Stolupin, V.A.; Yutlandov, I.A.

    1989-01-01

    The results of investigation of cold nuclear fusion on palladium are given both for electrolysis of heavy water D 2 O and mixture D 2 O + H 2 O) (1:1) and for palladium saturation with gaseous deuterium. The possibility of existance of this phenomenon was examined by detection of neutrons and gamma quanta from reactions: d + d → 3 He + n + 3.27 MeV, p + d → 3 He + γ + 5.5 MeV. Besides these reactions were identified by measuring the characteristic X radiation of palladium due to effect of charged products 3 He, p, t. The upper limits of the intensities of hypothetical sources of neutrons and gamma quanta at the 95% confidence level were obtained to be Q n ≤ 2x10 -2 n/sxcm 3 Pd, Q γ ≤ 2x10 -3 γ/sxcm 3 Pd. 2 refs.; 4 figs.; 2 tabs

  13. Wood construction under cold climate

    DEFF Research Database (Denmark)

    Wang, Xiaodong; Hagman, Olle; Sundqvist, Bror

    2014-01-01

    As wood constructions increasingly use engineered wood products worldwide, concerns arise about the integrity of the wood and adhesives system. The glueline stability is a crucial issue for engineered wood application, especially under cold climate. In this study, Norway spruce (Picea abies...... affected shear strength of wood joints. As temperature decreased, the shear strength decreased. PUR resin resulted in the strongest shear strength at all temperatures tested. MF resin responded to temperature changes in a similar ways as the PUR resin. The shear strength of wood joints with EPI resins...... specimens need to be tested in further work to more completely present the issue. The EN 301 and EN 302 may need to be specified based on wood species....

  14. Dismantling the Cold War economy

    International Nuclear Information System (INIS)

    Markusen, A.; Yudkin, J.

    1992-01-01

    End-of-the-Cold-War economic realities include political jockeying over the future of weapons systems, a paucity of meaningful conversion efforts, and a suspicion that a weak economy will be unable to compensate for the loss of jobs and purchasing power as defense budgets are reduced. The authors of this book present three interrelated hypotheses: The first is that the existence of a large military production sector has depleted the civilian economy of key resources and has preempted creation of the kind of broad-base civilian-oriented industrial policies needed for economic revitalization. The second is that a large military production sector creates barriers to the movement of resources. The third is that economic depletion and the barriers to moving resources to civilian production make conversion planning essential. This book explains why conversion is difficult, but offers only a few pages of specific conversion proposals

  15. Gauss Sum Factorization with Cold Atoms

    International Nuclear Information System (INIS)

    Gilowski, M.; Wendrich, T.; Mueller, T.; Ertmer, W.; Rasel, E. M.; Jentsch, Ch.; Schleich, W. P.

    2008-01-01

    We report the first implementation of a Gauss sum factorization algorithm by an internal state Ramsey interferometer using cold atoms. A sequence of appropriately designed light pulses interacts with an ensemble of cold rubidium atoms. The final population in the involved atomic levels determines a Gauss sum. With this technique we factor the number N=263193

  16. Mapping Anomalous Democracies During the Cold War

    DEFF Research Database (Denmark)

    Seeberg, Michael

    2014-01-01

    During the Cold War, a number of countries established stable democracies despite low levels of modernization and a relative lack of democratic neighbour countries—factors otherwise consistently related to the endurance of democracy. Meanwhile, the Cold War superpowers often supported autocracies...... are identified, including Bolivia, Botswana, Colombia, Costa Rica, Dominican Republic, Honduras, India, Jamaica, Mauritius, Trinidad and Tobago, and Turkey....

  17. Cold Medicines for Kids: What's the Risk?

    Science.gov (United States)

    ... cause colds. If your child has a cold, antibiotics won't help. Remember, the more your child uses antibiotics, the more likely he or she is to get sick with an antibiotic-resistant infection in the future. An ... treating them is to help your child feel comfortable. If you give your ...

  18. Cryogenic refrigeration for cold neutron sources

    International Nuclear Information System (INIS)

    Gistau-Baguer, Guy

    1998-01-01

    Neutron moderation by means of a fluid at cryogenic temperature is a very interesting way to obtain cold neutrons. Today, a number of nuclear research reactors are using this technology. This paper deals with thermodynamics and technology which are used for cooling Cold Neutron Sources

  19. Peripheral cold acclimatization in Antarctic scuba divers.

    Science.gov (United States)

    Bridgman, S A

    1991-08-01

    Peripheral acclimatization to cold in scuba divers stationed at the British Antarctic Survey's Signy Station was investigated during a year in Antarctica. Five divers and five non-diver controls underwent monthly laboratory tests of index finger immersion in cold water for 30 min. Index finger pulp temperature and time of onset of cold-induced vasodilatation (CIVD) were measured. Pain was recorded with verbal and numerical psychophysical subjective pain ratings. Average finger temperatures and median finger pain from 6-30 min of immersion, maximum finger temperatures during the first CIVD cycle, and finger temperatures at the onset of CIVD were calculated. Comparison of the variables recorded from divers and non-divers were performed with analysis of variance. No significant differences were found among the variables recorded from divers and non-divers. From a review of the literature, divers have responses typical of non-cold-adapted Caucasians. There is, therefore, no evidence that Signy divers peripherally acclimatized to cold. We suggest that these findings occur because either the whole body cooling which divers undergo inhibits peripheral acclimatization or because of insufficiently frequent or severe cold exposure while diving. Further basic studies on the duration, frequency and severity of cold exposure necessary to induce peripheral cold acclimatization are required before this question can be satisfactorily answered.

  20. Superfluorescence with cold trapped neon atoms

    International Nuclear Information System (INIS)

    Zachorowski, Jerzy

    2003-01-01

    A method for observation of superfluorescence in a cloud of cold metastable Ne atoms is proposed. Means of achieving a cold sample of trapped metastable atoms are discussed. The feasibility of obtaining conditions for a superfluorescence pulse is studied. The paper also discusses the prospects for obtaining intense pulses of extreme ultraviolet radiation

  1. THE COLD AND DARK PROCESS AT THE SAVANNAH RIVER SITE

    International Nuclear Information System (INIS)

    Gilmour, J; William Austin, W; Cathy Sizemore, C

    2007-01-01

    The deactivation and decommissioning (D and D) of a facility exposes D and D workers to numerous hazards. One of the more serious hazards is coming into contact to hazardous energy sources (e.g. electrical, pressurized steam). At the Savannah River Site (SRS) a formal process for identifying and eliminating sources of hazardous energy was developed and is called ''Cold and Dark''. Several ''near miss'' events involving cutting of energized conductors during D and D work in buildings thought to be isolated identified the need to have a formal process to identify and isolate these potentially hazardous systems. This process was developed using lessons learned from D and D activities at the Rocky Flats Environmental Technology Site (Rocky Flats) in Colorado. The Cold and Dark process defines an isolation boundary (usually a building perimeter) and then systematically identifies all of the penetrations through this boundary. All penetrations that involve hazardous energy sources are then physically air-gapped. The final product is a documented declaration of isolation performed by a team involving operations, engineering, and project management. Once the Cold and Dark declaration is made for a building work can proceed without the usual controls used in an operational facility (e.g. lockout/tagout, arc flash PPE). It is important to note that the Cold and Dark process does not remove all hazards from a facility. Work planning and controls still need to address hazards that can be present from such things as chemicals, radiological contamination, residual liquids, etc., as well as standard industrial hazards

  2. Improving cold chain systems: Challenges and solutions.

    Science.gov (United States)

    Ashok, Ashvin; Brison, Michael; LeTallec, Yann

    2017-04-19

    While a number of new vaccines have been rolled out across the developing world (with more vaccines in the pipeline), cold chain systems are struggling to efficiently support national immunization programs in ensuring the availability of safe and potent vaccines. This article reflects on the Clinton Health Access Initiative, Inc. (CHAI) experience working since 2010 with national immunization programs and partners to improve vaccines cold chains in 10 countries-Ethiopia, Nigeria, Kenya, Malawi, Tanzania, Uganda, Cameroon, Mozambique, Lesotho and India - to identify the root causes and solutions for three common issues limiting cold chain performance. Key recommendations include: Collectively, the solutions detailed in this article chart a path to substantially improving the performance of the cold chain. Combined with an enabling global and in-country environment, it is possible to eliminate cold chain issues as a substantial barrier to effective and full immunization coverage over the next few years. Copyright © 2017. Published by Elsevier Ltd.

  3. Social science in the Cold War.

    Science.gov (United States)

    Engerman, David C

    2010-06-01

    This essay examines ways in which American social science in the late twentieth century was--and was not--a creature of the Cold War. It identifies important work by historians that calls into question the assumption that all social science during the Cold War amounts to "Cold War social science." These historians attribute significant agency to social scientists, showing how they were enmeshed in both long-running disciplinary discussions and new institutional environments. Key trends in this scholarship include a broadening historical perspective to see social scientists in the Cold War as responding to the ideas of their scholarly predecessors; identifying the institutional legacies of World War II; and examining in close detail the products of extramural--especially governmental--funding. The result is a view of social science in the Cold War in which national security concerns are relevant, but with varied and often unexpected impacts on intellectual life.

  4. Properties of cold components of symbiotic stars

    International Nuclear Information System (INIS)

    Luud, L.; Leehdyarv, L.

    1986-01-01

    Using the Blackwell-Shallis method the luminosities, temperatures and radii for cold components of symbiotic stars and for a sample of field red giants have been determined by means of infrared photometric observations. It turned out that the cold components of symbiotic stars do not differ from the normal red giants of the asymptotic branch. The masses of cold components of symbiotic stars have been found to be close to 3 M* (M* is the solar mass).The cold components of symbiotic stars do not fill their Roche lobes. About 10 times more carbon stars than the normal value in the vicinity of the Sun have been found among the cold components of symbiotic stars

  5. Topology of Event Horizon

    OpenAIRE

    Siino, Masaru

    1997-01-01

    The topologies of event horizons are investigated. Considering the existence of the endpoint of the event horizon, it cannot be differentiable. Then there are the new possibilities of the topology of the event horizon though they are excluded in smooth event horizons. The relation between the topology of the event horizon and the endpoint of it is revealed. A torus event horizon is caused by two-dimensional endpoints. One-dimensional endpoints provide the coalescence of spherical event horizo...

  6. Relationships of self-identified cold tolerance and cold-induced vasodilatation in the finger

    Science.gov (United States)

    Park, Joonhee; Lee, Joo-Young

    2016-04-01

    This study was conducted to investigate relationships of self-identified cold tolerance and cold-induced vasodilatation (CIVD) in the finger. Nine males and 34 females participated in the following 2 tests: a CIVD test and a self-reported survey. The CIVD test was conducted 30-min cold-water immersion (3.8 ± 0.3 °C) of the middle finger at an air temperature of 27.9 ± 0.1 °C. The self-reported questionnaire consisted of 28 questions about whole and local body cold and heat tolerances. By a cluster analysis on the survey results, the participants were divided into two groups: high self-identified cold tolerance (HSCT, n = 25) and low self-identified cold tolerance (LSCT, n = 18). LSCT had lower self-identified cold tolerance ( P cold or heat tolerance had relationships with cold tolerance index, T max, and amplitude ( P cold tolerance classified through a standardized survey could be a good index to predict physiological cold tolerance.

  7. The impact of cold spells on mortality and effect modification by cold spell characteristics

    Science.gov (United States)

    Wang, Lijun; Liu, Tao; Hu, Mengjue; Zeng, Weilin; Zhang, Yonghui; Rutherford, Shannon; Lin, Hualiang; Xiao, Jianpeng; Yin, Peng; Liu, Jiangmei; Chu, Cordia; Tong, Shilu; Ma, Wenjun; Zhou, Maigeng

    2016-12-01

    In China, the health impact of cold weather has received little attention, which limits our understanding of the health impacts of climate change. We collected daily mortality and meteorological data in 66 communities across China from 2006 to 2011. Within each community, we estimated the effect of cold spell exposure on mortality using a Distributed Lag Nonlinear Model (DLNM). We also examined the modification effect of cold spell characteristics (intensity, duration, and timing) and individual-specific factors (causes of death, age, gender and education). Meta-analysis method was finally used to estimate the overall effects. The overall cumulative excess risk (CER) of non-accidental mortality during cold spell days was 28.2% (95% CI: 21.4%, 35.3%) compared with non-cold spell days. There was a significant increase in mortality when the cold spell duration and intensity increased or occurred earlier in the season. Cold spell effects and effect modification by cold spell characteristics were more pronounced in south China. The elderly, people with low education level and those with respiratory diseases were generally more vulnerable to cold spells. Cold spells statistically significantly increase mortality risk in China, with greater effects in southern China. This effect is modified by cold spell characteristics and individual-level factors.

  8. The Effect of Cold Showering on Health and Work: A Randomized Controlled Trial

    Science.gov (United States)

    Sierevelt, Inger N.; van der Heijden, Bas C. J. M.; Dijkgraaf, Marcel G.; Frings-Dresen, Monique H. W.

    2016-01-01

    Purpose The aim of this study was to determine the cumulative effect of a routine (hot-to-) cold shower on sickness, quality of life and work productivity. Methods Between January and March 2015, 3018 participants between 18 and 65 years without severe comorbidity and no routine experience of cold showering were randomized (1:1:1:1) to a (hot-to-) cold shower for 30, 60, 90 seconds or a control group during 30 consecutive days followed by 60 days of showering cold at their own discretion for the intervention groups. The primary outcome was illness days and related sickness absence from work. Secondary outcomes were quality of life, work productivity, anxiety, thermal sensation and adverse reactions. Results 79% of participants in the interventions groups completed the 30 consecutive days protocol. A negative binomial regression model showed a 29% reduction in sickness absence for (hot-to-) cold shower regimen compared to the control group (incident rate ratio: 0.71, P = 0.003). For illness days there was no significant group effect. No related serious advents events were reported. Conclusion A routine (hot-to-) cold shower resulted in a statistical reduction of self-reported sickness absence but not illness days in adults without severe comorbidity. Trial Registration Netherlands National Trial Register NTR5183 PMID:27631616

  9. Tolerance to multiple climate stressors: A case study of Douglas-fir drought and cold hardiness

    Science.gov (United States)

    Bansal, Sheel; Harrington, Constance A; St. Clair, John Bradley

    2016-01-01

    Summary: 1. Drought and freeze events are two of the most common forms of climate extremes which result in tree damage or death, and the frequency and intensity of both stressors may increase with climate change. Few studies have examined natural covariation in stress tolerance traits to cope with multiple stressors among wild plant populations. 2. We assessed the capacity of coastal Douglas-fir (Pseudotsuga menziesii var. menziesii), an ecologically and economically important species in the northwestern USA, to tolerate both drought and cold stress on 35 populations grown in common gardens. We used principal components analysis to combine drought and cold hardiness trait data into generalized stress hardiness traits to model geographic variation in hardiness as a function of climate across the Douglas-fir range. 3. Drought and cold hardiness converged among populations along winter temperature gradients and diverged along summer precipitation gradients. Populations originating in regions with cold winters had relatively high tolerance to both drought and cold stress, which is likely due to overlapping adaptations for coping with winter desiccation. Populations from regions with dry summers had increased drought hardiness but reduced cold hardiness, suggesting a trade-off in tolerance mechanisms. 4. Our findings highlight the necessity to look beyond bivariate trait–climate relationships and instead consider multiple traits and climate variables to effectively model and manage for the impacts of climate change on widespread species.

  10. Event segmentation ability uniquely predicts event memory.

    Science.gov (United States)

    Sargent, Jesse Q; Zacks, Jeffrey M; Hambrick, David Z; Zacks, Rose T; Kurby, Christopher A; Bailey, Heather R; Eisenberg, Michelle L; Beck, Taylor M

    2013-11-01

    Memory for everyday events plays a central role in tasks of daily living, autobiographical memory, and planning. Event memory depends in part on segmenting ongoing activity into meaningful units. This study examined the relationship between event segmentation and memory in a lifespan sample to answer the following question: Is the ability to segment activity into meaningful events a unique predictor of subsequent memory, or is the relationship between event perception and memory accounted for by general cognitive abilities? Two hundred and eight adults ranging from 20 to 79years old segmented movies of everyday events and attempted to remember the events afterwards. They also completed psychometric ability tests and tests measuring script knowledge for everyday events. Event segmentation and script knowledge both explained unique variance in event memory above and beyond the psychometric measures, and did so as strongly in older as in younger adults. These results suggest that event segmentation is a basic cognitive mechanism, important for memory across the lifespan. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. Temperature studies with the Asian citrus psyllid, Diaphorina citri: cold hardiness and temperature thresholds for oviposition.

    Science.gov (United States)

    Hall, David G; Wenninger, Erik J; Hentz, Matthew G

    2011-01-01

    This study was conducted to obtain information on the cold hardiness of the Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae), in Florida and to assess upper and lower temperature thresholds for oviposition. The psyllid is an important pest in citrus because it transmits the bacterial pathogens responsible for citrus greening disease, Huanglongbing, considered the most serious citrus disease worldwide. D. citri was first found in Florida during 1998, and the disease was discovered during 2005. Little was known regarding cold hardiness of D. citri, but Florida citrus is occasionally subjected to notable freeze events. Temperature and duration were each significant sources of variation in percent mortality of D. citri subjected to freeze events. Relatively large percentages of adults and nymphs survived after being exposed for several hours to temperatures as low as -5 to -6 °C. Relatively large percentages of eggs hatched after being exposed for several hours to temperatures as low as -8 °C. Research results indicated that adult D. citri become cold acclimated during the winter through exposure to cooler winter temperatures. There was no evidence that eggs became cold acclimated during winter. Cold acclimation in nymphs was not investigated. Research with adult D. citri from laboratory and greenhouse colonies revealed that mild to moderate freeze events were usually nonlethal to the D. citri irrespective of whether they were cold acclimated or not. Upper and lower temperature thresholds for oviposition were investigated because such information may be valuable in explaining the geographic distribution and potential spread of the pest from Florida as well as how cooler winter temperatures might limit population growth. The estimated lower and upper thresholds for oviposition were 16.0 and 41.6 °C, respectively; the estimated temperature of peak oviposition over a 48 h period was 29.6 °C.

  12. The Cold Chain Logistics for Perishable Agricultural Products in China

    OpenAIRE

    Hou Yanfang; Xie Dong; Wang Jianbo

    2015-01-01

    This study introduces concepts of the agricultural product cold chain logistics and domestic and international researches. Also, the study discusses issues of Chinese agricultural cold chain logistics in the development process as the following aspects: the dividing of cold chain logistics market, refrigeration hardware facilities, third-party cold chain logistics development, the level of cold chain technologies, cold chain logistics professionals and the legal system and the standard system...

  13. Effects of life event stress, exercise workload, hardiness and coping ...

    African Journals Online (AJOL)

    Effects of life event stress, exercise workload, hardiness and coping style on susceptibility to the common cold. GA Struwig, M Papaikonomou, P Kruger. Abstract. No Abstract. South African Journal for Physical, Health Education, Recreation and DanceVol. 12(4) 2006: pp. 369-383. Full Text: EMAIL FULL TEXT EMAIL FULL ...

  14. Workshop on cold-blanket research

    International Nuclear Information System (INIS)

    1977-05-01

    The objective of the workshop was to identify and discuss cold-plasma blanket systems. In order to minimize the bombardment of the walls by hot neutrals the plasma should be impermeable. This requires a density edge-thickness product of nΔ > 10 15 cm -2 . An impermeable cold plasma-gas blanket surrounding a hot plasma core reduces the plasma wall/limiter interaction. Accumulation of impurities in this blanket can be expected. Fuelling from a blanket may be possible as shown by experimental results, though not fully explained by classical transport of neutrals. Refuelling of a reacting plasma had to be ensured by inward diffusion. Experimental studies of a cold impermeable plasma have been done on the tokamak-like Ringboog device. Simulation calculations for the next generation of large tokamaks using a particular transport model, indicate that the plasma edge profile can be controlled to reduce the production of sputtered impurities to an acceptable level. Impurity control requires a small fraction of the radial space to accomodate the cold-plasma layer. The problem of exhaust is, however, more complicated. If the cold-blanket scheme works as predicted in the model calculations, then α-particles generated by fusion will be transported to the cold outside layer. The Communities' experimental programme of research has been discussed in terms of the tokamaks which are available and planned. Two options present themselves for the continuation of cold-blanket research

  15. Acute Cold / Restraint Stress in Castrated Rats

    Directory of Open Access Journals (Sweden)

    Farideh Zafari Zangeneh

    2008-09-01

    Full Text Available Objective: The present study aimed to determine whether castration altered osmotically stimulated vasopressin (VP release and urinary volume and what is the role of endocrine-stress axis in this process.Materials and methods: Totally 108 mice were studied in two main groups of castrated (n=78 and control (n=30. Each group was extracted by acute cold stress (4◦C for 2h/day, restraint stress (by syringes 60cc 2h/day and cold/restraint stress. The castrated group was treated in sub groups of testosterone, control (sesame oil as vehicle of testosterone. Propranolol as blocker of sympathetic nervous system was given to both groups of castrated mice and main control.Results: Our results showed that, there is interactions between testosterone and sympathetic nervous system on vasopressin, because urine volume was decreased only in testoctomized mice with cold/restraint and cold stress (P<0.001; propranolol as the antagonist of sympathetic nervous system could block and increase urine volume in castrated mice. This increased volume of urine was due to acute cold stress, not restraint stress (p<0.001. The role of testosterone, noradrenalin (NA and Vasopressin (VP in the acute cold stress is confirmed, because testosterone could return the effect of decreased urine volume in control group (P<0.001. Conclusion: Considering the effect of cold/restraint stress on urinary volume in castrated mice shows that there is interaction between sex hormone (testosterone, vasopressin and adrenergic systems.

  16. Inhibition of TRPM8 channels reduces pain in the cold pressor test in humans.

    Science.gov (United States)

    Winchester, Wendy J; Gore, Katrina; Glatt, Sophie; Petit, Wendy; Gardiner, Jennifer C; Conlon, Kelly; Postlethwaite, Michael; Saintot, Pierre-Philippe; Roberts, Sonia; Gosset, James R; Matsuura, Tomomi; Andrews, Mark D; Glossop, Paul A; Palmer, Michael J; Clear, Nicola; Collins, Susie; Beaumont, Kevin; Reynolds, David S

    2014-11-01

    The transient receptor potential (subfamily M, member 8; TRPM8) is a nonselective cation channel localized in primary sensory neurons, and is a candidate for cold thermosensing, mediation of cold pain, and bladder overactivity. Studies with TRPM8 knockout mice and selective TRPM8 channel blockers demonstrate a lack of cold sensitivity and reduced cold pain in various rodent models. Furthermore, TRPM8 blockers significantly lower body temperature. We have identified a moderately potent (IC50 = 103 nM), selective TRPM8 antagonist, PF-05105679 [(R)-3-[(1-(4-fluorophenyl)ethyl)(quinolin-3-ylcarbonyl)amino]methylbenzoic acid]. It demonstrated activity in vivo in the guinea pig bladder ice water and menthol challenge tests with an IC50 of 200 nM and reduced core body temperature in the rat (at concentrations >1219 nM). PF-05105679 was suitable for acute administration to humans and was evaluated for effects on core body temperature and experimentally induced cold pain, using the cold pressor test. Unbound plasma concentrations greater than the IC50 were achieved with 600- and 900-mg doses. The compound displayed a significant inhibition of pain in the cold pressor test, with efficacy equivalent to oxycodone (20 mg) at 1.5 hours postdose. No effect on core body temperature was observed. An unexpected adverse event (hot feeling) was reported, predominantly periorally, in 23 and 36% of volunteers (600- and 900-mg dose, respectively), which in two volunteers was nontolerable. In conclusion, this study supports a role for TRPM8 in acute cold pain signaling at doses that do not cause hypothermia. Copyright © 2014 by The American Society for Pharmacology and Experimental Therapeutics.

  17. Cold vacuum drying facility site evaluation report

    International Nuclear Information System (INIS)

    Diebel, J.A.

    1996-01-01

    In order to transport Multi-Canister Overpacks to the Canister Storage Building they must first undergo the Cold Vacuum Drying process. This puts the design, construction and start-up of the Cold Vacuum Drying facility on the critical path of the K Basin fuel removal schedule. This schedule is driven by a Tri-Party Agreement (TPA) milestone requiring all of the spent nuclear fuel to be removed from the K Basins by December, 1999. This site evaluation is an integral part of the Cold Vacuum Drying design process and must be completed expeditiously in order to stay on track for meeting the milestone

  18. Cold valleys in fusion and fission

    International Nuclear Information System (INIS)

    Misicu, S.

    2003-01-01

    The cold fission configuration after the preformation of the fragments resembles a short-lived dinuclear or quasi-molecular system. The most conceivable scission configuration is given by two fission fragments in touching with the symmetry axes aligned (pole-pole orientation). This conclusion was based on the simple argument that this configuration offers the optimal tunneling time, i.e. the difference between the Coulomb barrier and the decay energy Q is minimal. Other orientations are apparently precluded in cold spontaneous fission and should be regarded as quasi-fission doorways in the synthesis of superheavy elements by cold fusion. (orig.)

  19. Preparation of translationally cold neutral molecules.

    Science.gov (United States)

    Di Domenicantonio, Giulia; Bertsche, Benjamin; Osterwalder, Andreas

    2011-01-01

    Efforts at EPFL to obtain translationally cold neutral molecules are described. Active deceleration of polar molecules is performed by confining the molecules in moving three-dimensional electrostatic traps, and by appropriately choosing the velocity of those traps. Alternatively, cold molecules can be obtained by velocity filtering. Here, the velocity of the molecules is not changed, but instead the cold molecules are extracted from a thermal sample by using the competition between the electrostatic force and the centrifugal force inside a bent electrostatic guide for polar molecules.

  20. Cold stress alters transcription in meiotic anthers of cold tolerant chickpea (Cicer arietinum L.).

    Science.gov (United States)

    Sharma, Kamal Dev; Nayyar, Harsh

    2014-10-11

    Cold stress at reproductive phase in susceptible chickpea (Cicer arietinum L.) leads to pollen sterility induced flower abortion. The tolerant genotypes, on the other hand, produce viable pollen and set seed under cold stress. Genomic information on pollen development in cold-tolerant chickpea under cold stress is currently unavailable. DDRT-PCR analysis was carried out to identify anther genes involved in cold tolerance in chickpea genotype ICC16349 (cold-tolerant). A total of 9205 EST bands were analyzed. Cold stress altered expression of 127 ESTs (90 up-regulated, 37 down-regulated) in anthers, more than two third (92) of which were novel with unknown protein identity and function. Remaining about one third (35) belonged to several functional categories such as pollen development, signal transduction, ion transport, transcription, carbohydrate metabolism, translation, energy and cell division. The categories with more number of transcripts were carbohydrate/triacylglycerol metabolism, signal transduction, pollen development and transport. All but two transcripts in these categories were up-regulated under cold stress. To identify time of regulation after stress and organ specificity, expression levels of 25 differentially regulated transcripts were also studied in anthers at six time points and in four organs (anthers, gynoecium, leaves and roots) at four time points. Limited number of genes were involved in regulating cold tolerance in chickpea anthers. Moreover, the cold tolerance was manifested by up-regulation of majority of the differentially expressed transcripts. The anthers appeared to employ dual cold tolerance mechanism based on their protection from cold by enhancing triacylglycerol and carbohydrate metabolism; and maintenance of normal pollen development by regulating pollen development genes. Functional characterization of about two third of the novel genes is needed to have precise understanding of the cold tolerance mechanisms in chickpea anthers.

  1. Seek and you shall find--but then what do you do? Cold agglutinins in cardiopulmonary bypass and a single-center experience with cold agglutinin screening before cardiac surgery.

    Science.gov (United States)

    Jain, Michael D; Cabrerizo-Sanchez, Rosa; Karkouti, Keyvan; Yau, Terrence; Pendergrast, Jacob M; Cserti-Gazdewich, Christine M

    2013-04-01

    Cardiopulmonary bypass (CPB) during cardiac surgery can involve deliberate hypothermia of the systemic (22-36 °C) and coronary circulations (as low as 8-12 °C). Adverse sequelae of cold-active antibodies have been feared and reported under such conditions, and some centers thus elect to screen for cold agglutinins before CPB. We reviewed the literature on cold agglutinins in cardiac surgery and described the yields and effects of cold agglutinin screening (CAS) in 14,900 cardiac surgery patients undergoing CPB over 8 years at a single institution. Cold agglutinin screening was positive in 47 cases (0.3%), at an annual testing cost of $17,000 CAD. The response of the surgical team to the preoperative discovery of a cold agglutinin was variable, with CPB modified to avoid hypothermia in approximately one-third of cases. In patients discovered to have a positive CAS, postoperative intensive care unit and hospital length of stay were marginally increased (54.6 vs. 42.8 hours, P = .02; 7 [6-14] vs. 7 [5-9] days, P = .04). However, the composite of mortality or severe morbidity (stroke, myocardial infarction, dialysis, low output syndrome, sepsis, and deep vein thrombosis) was not significantly different (14.9% vs. 9.2%, P = .2). Antibody verification found that only 43% of positive CAS patients had true cold agglutinins (20 patients). Furthermore, the rate of adverse events was low in both CAS-positive and true-positive cold agglutinin patients undergoing CPB and cardiac surgery. Finally, modification of CPB to attenuate hypothermia did not decrease adverse events. Based upon historical and local data, preclinical CAS is cost-substantial and nonspecific. Cold agglutinin screening does not promote an algorithm of care that meaningfully improves patient CPB outcomes. Copyright © 2013 Elsevier Inc. All rights reserved.

  2. Last Deglaciation Events (16.1-11.4 cal-Ka) Recorded in a Speleothem from DeSoto Caverns, Alabama, U.S.A.

    Science.gov (United States)

    Lambert, W. J.; Aharon, P.; Hellstrom, J.

    2007-12-01

    Whereas the rapid climate swings that occurred during the last deglaciation have been well documented in the Greenland ice cores, their cause/s continue to be a subject of heated debate. Clearly, more geographically dispersed records are required in order to provide better insight into the history of deglaciation, and by extension into the cause/s of the abrupt climate shifts. Particularly scarce are continental deglaciation records from the southeast North America whose atmospheric conditions were controlled by the retreating Laurentide Ice Sheet to the north and the Gulf of Mexico warm waters to the south. In order to remedy the absence of deglaciation records in the Southeast USA in general, and the Gulf Coast in particular, we have initiated a study of a 55-cm long stalagmite (DSSG-2) from the DeSoto Caverns in Childersburg, Alabama (33° 18'N, 86° 17'W). Seven radiocarbon AMS and eighteen U/Th TIMS dates reveal that the continuously layered stalagmite covers the time interval 31 to 11.4 cal-Ka at growth rates varying from 61 μm/decade at the start of deglaciation and up to 2700 μm/decade close to its termination. The combination of unusually high growth rates, pristine aragonite mineralogy and tight sampling (n=602) afforded generation of high fidelity δ13C and δ18O records from about 16.1 to 11.4 cal-Ka whose high resolution is comparable with the contemporaneous Greenland ice core records. The stalagmite δ18O record shows excellent agreement in relative amplitude shifts and timing of abrupt and brief cold reversals (Oldest Dryas, Older Dryas, Inter-Allerød Cold Period) that punctuated the overall trend of deglaciation warming (Bølling/Allerød period). The succeeding Younger Dryas is depicted in the stalagmite by rapid positive shifts in δ18O and δ13C of 1.3‰ and 2.3‰ (V-PDB) relative to the baseline mean value and its start and termination (12.7-11.8 Ka) are concordant within error with the dates reported from GISP2 ice core (12.82-11.60 Ka

  3. Cold fusion research in Italy

    International Nuclear Information System (INIS)

    Scaramuzzi, F.

    1993-01-01

    This paper summarizes cold fusion (CF) research in Italy. In Italy, many Agencies and Universities are moderately funding research in CF, and the scientists have made a few attempts to coordinate each other, organizing meetings and conferences. However, the activity has been mostly the fruit of the scientists' initiative, and never a coordinated proposal of Agencies and Universities. No position on the scientific validity of the subject has been officially taken and the funds for CF have been rather modest. The investments in Italy on CF, the figure referring to 1992 amounts to about 0.5 million dollars, not including expenses for personnel. A number of about 70 scientists, mostly working part-time, is committed all around the Country in research on CF. The lack of offical commitment and effective support by the Research Agencies and the Universities has not prevented scientists from being quite active in performing research. On the other side, it has to be acknowledged that no formal vetoes have been interposed to the free initiative of scientists in this field: on the contrary, some of the Agencies and Universities have moderately funded such an effort. The quality of the experiments in Italy has been increasingly good, and the results obtained are rather out standing in the general panorama of CF. But it is time to perform a more coordinated effort, keeping in mind that material science aspects, such as the characteristics of the materials used, play a very important role in the development of this topic. Thus, a much more intense effort is required to obtain a more substantial progress in the field. The increasingly convincing results obtained by the whole CF community, and the example of the Japanese Government and Industry, which appear to be determined to promoting CF research, have changed the panorama of CF. These are now signs that also the Italian scientific authorities could consider favouring research in this field in the near future. (J.P.N.)

  4. Observations of Cold Pool Properties during GoAmazon2014/5

    Science.gov (United States)

    Mayne, S. L.; Schumacher, C.; MacDonald, L.; Turner, D. D.

    2017-12-01

    Convectively generated cold pools are instrumental in both the development of the sub-cloud layer and the organization of deep convection. Despite this, analyses of cold pools in the tropics are constrained by a lack of observational data; insight into the phenomena therefore relies heavily on numerical models. GoAmazon2014/5, a 2-year DOE-sponsored field campaign centered on Manacapuru, Brazil in the central Amazon, provides a unique opportunity to characterize tropical cold pools and allows for the comparison of observational data with theoretical results from model cold pool simulations and parameterizations. This investigation analyzes radar, disdrometer, and profiler measurements at the DOE mobile facility site to study tropical cold pool characteristics. The Brazilian military (SIPAM) operational S-band radar in Manaus is used to provide a broad context of convective systems, while measurements from Parsivel disdrometers are used to assess drop-size distributions (DSDs) at the surface. A unique aspect of this research is the use of the Atmospheric Emitted Radiance Interferometer (AERI) instrument, which utilizes down-welling IR measurements to obtain vertical profiles of thermodynamic quantities such as temperature and water vapor in the lowest few km of the atmosphere. Combined with surface observations and sounding data, these datasets will result in a thorough investigation of the horizontal and vertical characteristics of cold pools over the tropical rain forest. Preliminary analyses of 20 events reveal a mean cold pool height of 220 m and a mean radius of approximately 8.5 km. The average cold pool experienced a temperature (specific humidity) decrease of approximately 1 K (0.4 g/kg) at the surface. The temperature decrease is consistent with modeling studies and limited observations from previous studies over the tropics. The small decrease in specific humidity is attributed to the high moisture content within the cold pools. AERI retrievals of

  5. Thyroid transcriptome analysis reveals different adaptive responses to cold environmental conditions between two chicken breeds.

    Science.gov (United States)

    Xie, Shanshan; Yang, Xukai; Wang, Dehe; Zhu, Feng; Yang, Ning; Hou, Zhuocheng; Ning, Zhonghua

    2018-01-01

    , and showed higher responsiveness in BS compared with RIR chickens, suggesting greater adaptability of the thyroid in BS chickens. Moreover, 10,053 differential splicing events were revealed among the groups, with RNA splicing and processing, gene expression, transport, and metabolism being the main affected biological processes, identifying a valuable alternative splicing repertoire for the chicken thyroid. A short isoform of TPO (encoding thyroid peroxidase) containing multiple open reading frames was generated in both breeds by skipping exons 4 and 5 in the cold environment. These findings provide novel clues for future studies of the molecular mechanisms underlying cold adaptation and/or acclimation in chickens.

  6. Event dependent sampling of recurrent events

    DEFF Research Database (Denmark)

    Kvist, Tine Kajsa; Andersen, Per Kragh; Angst, Jules

    2010-01-01

    The effect of event-dependent sampling of processes consisting of recurrent events is investigated when analyzing whether the risk of recurrence increases with event count. We study the situation where processes are selected for study if an event occurs in a certain selection interval. Motivation...... retrospective and prospective disease course histories are used. We examine two methods to correct for the selection depending on which data are used in the analysis. In the first case, the conditional distribution of the process given the pre-selection history is determined. In the second case, an inverse...

  7. Caring for Your Child's Cold or Flu

    Science.gov (United States)

    ... Print Share Caring for Your Child’s Cold or Flu Page Content ​Unfortunately, there's no cure for the ... or spoon) that is marked in milliliters. Prevention: Flu vaccine Children 6 months or older should get ...

  8. International cooperation in cold forging technology

    DEFF Research Database (Denmark)

    Bay, Niels; Lange, K

    1992-01-01

    International cooperation in the field of cold forging technology started in 1961 by formation of the OECD Group of Experts on Metal Forming. In 1967 this group was transformed into the International Cold Forging Group, ICFG, an independent body which has now been operative for 25 years. Members...... of the ICFG are personally elected by the Plenary as experts within the field, often representing national groups within cold forging. The main work within the ICFG is carried out in its subgroups which are established by the Plenary to collect, compile and evaluate data and eventually also produce data...... by cooperative activities or by instigating national research. These subgroups have produced 9 data sheets and 7 guidelines on subjects such as materials, tool design and construction, calculation methods for cold forging tools, manufacture of slugs, lubrication aspects and small quantity production. Plenary...

  9. Common Cold in Babies: Symptoms and Causes

    Science.gov (United States)

    ... clear at first but might thicken and turn yellow or green Other signs and symptoms of a common cold in a baby may include: Fever Sneezing Coughing Decreased appetite Irritability Difficulty sleeping Trouble ...

  10. Sustainable construction in remote cold regions.

    Science.gov (United States)

    2015-12-01

    The goal of this project was to identify sustainable construction techniques appropriate for remote and cold regions, some of which apply to : operations and maintenance as well. The vast body of literature regarding green construction in warm region...

  11. Cold vacuum drying facility design requirements

    Energy Technology Data Exchange (ETDEWEB)

    Irwin, J.J.

    1997-09-24

    This release of the Design Requirements Document is a complete restructuring and rewrite to the document previously prepared and released for project W-441 to record the design basis for the design of the Cold Vacuum Drying Facility.

  12. Cold vacuum drying facility design requirements

    International Nuclear Information System (INIS)

    Irwin, J.J.

    1997-01-01

    This release of the Design Requirements Document is a complete restructuring and rewrite to the document previously prepared and released for project W-441 to record the design basis for the design of the Cold Vacuum Drying Facility

  13. Cold quark matter in compact stars

    Energy Technology Data Exchange (ETDEWEB)

    Franzon, B.; Fogaca, D. A.; Navarra, F. S. [Instituto de Fisica, Universidade de Sao Paulo Rua do Matao, Travessa R, 187, 05508-090 Sao Paulo, SP (Brazil); Horvath, J. E. [Instituto de Astronomia, Geofisica e Ciencias Atmosfericas, Universidade de Sao Paulo, Rua do Matao, 1226, 05508-090, Sao Paulo, SP (Brazil)

    2013-03-25

    We used an equation of state for the cold quark matter to the study of properties of quark stars. We also discuss the absolute stability of quark matter and compute the mass-radius relation for self-bound stars.

  14. Shaft Seal Compensates for Cold Flow

    Science.gov (United States)

    Myers, W. N.; Hein, L. A.

    1985-01-01

    Seal components easy to install. Ring seal for rotating or reciprocating shafts spring-loaded to compensate for slow yielding (cold flow) of sealing material. New seal relatively easy to install because components preassembled, then installed in one piece.

  15. fabrics induced by cold plasma treatments

    Indian Academy of Sciences (India)

    Some selective cold plasma processing modify specific surface properties of ... obtain information on the chemical and physical processing involved in ... charges of suitable gases. such plasma species can give rise to several concurrent.

  16. Sizing Post-Cold War Nuclear Forces

    National Research Council Canada - National Science Library

    Oelrich, I

    2001-01-01

    This study addresses the utility of, and need for, nuclear weapons a decade after the end of the Cold War with special focus on the numbers and types of nuclear weapons appropriate for particular requirements...

  17. Accelerator-based pulsed cold neutron source

    International Nuclear Information System (INIS)

    Inoue, Kazuhiko; Iwasa, Hirokatsu; Kiyanagi, Yoshiaki

    1979-01-01

    An accelerator-based pulsed cold neutron source was constructed. The accelerator is a 35 MeV electron linear accelerator with 1 kW average beam power. The cold neutron beam intensity at a specimen is equivalent to that of a research reactor of 10 14 n/cm 2 .s thermal flux in the case of the quasi-elastic neutron scattering measurements. In spite of some limitations to the universal uses, it has been demonstrated by this facility that the modest capacity accelerator-based pulsed cold neutron source is a highly efficient cold neutron source with low capital investment. Design philosophy, construction details, performance and some operational experiences are described. (author)

  18. Tips to Protect Workers in Cold Environments

    Science.gov (United States)

    ... Z Index | Newsroom | Contact Us | FAQs | About OSHA OSHA ... health problems such as trench foot, frostbite and hypothermia. In extreme cases, including cold water immersion, exposure can lead to ...

  19. Cold fusion reactors and new modern physics

    OpenAIRE

    Huang Zhenqiang Huang Yuxiang

    2013-01-01

    The author of the "modern physics classical particle quantization orbital motion model general solution", referred to as the “new modern physics” a book. “The nuclear force constraint inertial guidance cold nuclear fusion collides” patent of invention referred to as the “cold nuclear fusion reactor” detailed technical data. Now provide to you, hope you help spread and the mainstream of modern physics of academic and fusion engineering academic communication. We work together to promote the c...

  20. Some concluding remarks about cold moderator development

    International Nuclear Information System (INIS)

    Carpenter, J.M.

    1990-01-01

    This paper is the transcription of remarks made at the conclusion of the Workshop on Cold Neutron Sources held at the Los Angeles National Laboratory, Los Alamos, New Mexico, March 5--7, 1990. Areas of interest include the following: scattering functions; cold moderator materials; radiation mixing of chemical composition; comparison of some pulsed moderator spectra; hydrogen mixtures; premoderators and shields; composite reflectors; exotic moderator materials; deuterated methanes; mixed moderator materials; and test facility availabilities. 2 refs., 4 figs., 1 tab

  1. Cold stress induces lower urinary tract symptoms.

    Science.gov (United States)

    Imamura, Tetsuya; Ishizuka, Osamu; Nishizawa, Osamu

    2013-07-01

    Cold stress as a result of whole-body cooling at low environmental temperatures exacerbates lower urinary tract symptoms, such as urinary urgency, nocturia and residual urine. We established a model system using healthy conscious rats to explore the mechanisms of cold stress-induced detrusor overactivity. In this review, we summarize the basic findings shown by this model. Rats that were quickly transferred from room temperature (27 ± 2°C) to low temperature (4 ± 2°C) showed detrusor overactivity including increased basal pressure and decreased voiding interval, micturition volume, and bladder capacity. The cold stress-induced detrusor overactivity is mediated through a resiniferatoxin-sensitve C-fiber sensory nerve pathway involving α1-adrenergic receptors. Transient receptor potential melastatin 8 channels, which are sensitive to thermal changes below 25-28°C, also play an important role in mediating the cold stress responses. Additionally, the sympathetic nervous system is associated with transient hypertension and decreases of skin surface temperature that are closely correlated with the detrusor overactivity. With this cold stress model, we showed that α1-adrenergic receptor antagonists have the potential to treat cold stress-exacerbated lower urinary tract symptoms. In addition, we showed that traditional Japanese herbal mixtures composed of Hachimijiogan act, in part, by increasing skin temperature and reducing the number of cold sensitive transient receptor potential melastatin channels in the skin. The effects of herbal mixtures have the potential to treat and/or prevent the exacerbation of lower urinary tract symptoms by providing resistance to the cold stress responses. Our model provides new opportunities for utilizing animal disease models with altered lower urinary tract functions to explore the effects of novel therapeutic drugs. © 2013 The Japanese Urological Association.

  2. Superior cold recycling : The score project

    OpenAIRE

    LESUEUR, D; POTTI, JJ; SOUTHWELL, C; WALTER, J; CRUZ, M; DELFOSSE, F; ECKMANN, B; FIEDLER, J; RACEK, I; SIMONSSON, B; PLACIN, F; SERRANO, J; RUIZ, A; KALAAJI, A; ATTANE, P

    2004-01-01

    In order to develop Environmentally Friendly Construction Technologies (EFCT) and as part of the 5th Framework Program of Research and Development, the European Community has decided to finance a research project on cold recycling, entitled SCORE "Superior COld REcycling based on benefits of bituminous microemulsions and foamed bitumen. A EFCT system for the rehabilitation and the maintenance of roads". This research project gathers organizations from all over Europe, from industrial partners...

  3. [Imperial Oil's Cold Lake oil sands operations

    International Nuclear Information System (INIS)

    Dingle, H. B.

    1999-01-01

    Imperial Oil Limited's Cold Lake oil sands resources, production and operations in Alberta are discussed. Cold Lake is the company's largest single asset and its largest source of crude oil production. In 1998, Cold Lake accounted for just under half of Imperial's total liquid production, averaging more than 135,000 barrels of bitumen a day. Despite the very difficult operating conditions experienced by the oil sands industry in 1998, Imperial Oil's Cold Lake operations generated a positive cash flow and earnings. Just as important, the near and long-term potential of Cold Lake property continues to be strong, even with the tough market conditions today and the foreseeable future. Proved reserves at the end of 1997 were 1.3 billions barrels, equal to about 24 years of current production, but even more important is Imperial's resource base in the Athabasca region, which represents 150 years of production at current rates. Although production forecasts for the near future are are revised downward because of production shut-in due to low prices, the company is confident of its long-term prospects mainly because of existing infrastructure, superior reservoir quality, 30 years worth of operating improvements and established bitumen-blend markets. Details of the company's future Cold Lake development plans are discussed. The need to continue technology development, which has been at the core of the industry's growth in the past and will continue to be the key to the future, are emphasized

  4. Thinking about the cold fusion fever

    International Nuclear Information System (INIS)

    Kitsunezaki, Akio

    1989-01-01

    The excitement since March 23 on cold fusion seems to be unprecedented evidence that the people of the world are waiting for fusion power with much enthusiasm. Cold fusion is really a surprise because it does not need high temperature and because it seems to be easy to enlarge the test tube into a useful power source if the claim by Professors Pons and Fleischmann at the University of Utah are true. The second announcement of cold fusion came from the Brigham Young University, also in the state of Utah, by Professor Jones, but his report was totally different from that given by Pons and Fleischmann. From the beginning of the 'fever', physicists have been very skeptical about cold fusion. Most of the critics and criticisms are targeted on Pons and Fleischmann rather than Jones, because not only was their paper poor but also their statements have not been scientific. They insisted that the heat came from fusion reaction, but without any scientific proof. They had not carried out the basic control experiment by running the same test with ordinary water instead of heavy water. A meeting on cold fusion was held at JAERI on May 15. At the end of the meeting, the some 260 attendants knew that cold fusion was not conceivable with the current scientific knowledge. (N.K.)

  5. Studies and modeling of cold neutron sources

    International Nuclear Information System (INIS)

    Campioni, G.

    2004-11-01

    With the purpose of updating knowledge in the fields of cold neutron sources, the work of this thesis has been run according to the 3 following axes. First, the gathering of specific information forming the materials of this work. This set of knowledge covers the following fields: cold neutron, cross-sections for the different cold moderators, flux slowing down, different measurements of the cold flux and finally, issues in the thermal analysis of the problem. Secondly, the study and development of suitable computation tools. After an analysis of the problem, several tools have been planed, implemented and tested in the 3-dimensional radiation transport code Tripoli-4. In particular, a module of uncoupling, integrated in the official version of Tripoli-4, can perform Monte-Carlo parametric studies with a spare factor of Cpu time fetching 50 times. A module of coupling, simulating neutron guides, has also been developed and implemented in the Monte-Carlo code McStas. Thirdly, achieving a complete study for the validation of the installed calculation chain. These studies focus on 3 cold sources currently functioning: SP1 from Orphee reactor and 2 other sources (SFH and SFV) from the HFR at the Laue Langevin Institute. These studies give examples of problems and methods for the design of future cold sources

  6. Cold water recovery reduces anaerobic performance.

    Science.gov (United States)

    Crowe, M J; O'Connor, D; Rudd, D

    2007-12-01

    This study investigated the effects of cold water immersion on recovery from anaerobic cycling. Seventeen (13 male, 4 female) active subjects underwent a crossover, randomised design involving two testing sessions 2 - 6 d apart. Testing involved two 30-s maximal cycling efforts separated by a one-hour recovery period of 10-min cycling warm-down followed by either passive rest or 15-min cold water immersion (13 - 14 degrees C) with passive rest. Peak power, total work and postexercise blood lactate were significantly reduced following cold water immersion compared to the first exercise test and the control condition. These variables did not differ significantly between the control tests. Peak exercise heart rate was significantly lower after cold water immersion compared to the control. Time to peak power, rating of perceived exertion, and blood pH were not affected by cold water immersion compared to the control. Core temperature rose significantly (0.3 degrees C) during ice bath immersion but a similar increase also occurred in the control condition. Therefore, cold water immersion caused a significant decrease in sprint cycling performance with one-hour recovery between tests.

  7. Cold neutron source with self-regulation

    International Nuclear Information System (INIS)

    Kawai, T.

    2003-01-01

    A way to increase the cold neutron flux is to cool moderator from where cold neutrons are extracted. Although various kinds of cooling system are considered, the closed thermo-siphon cooling system is adopted in many institutes. The notable feature of this system is to be able to keep the liquid level stable in the moderator cell against thermal disturbances, by using self-regulation, which allows a stable supply of cold neutrons. The main part of the closed thermo-siphon consists of a condenser, a moderator transfer tube and moderator cell, which is called the hydrogen cold system. When an extra heat load is applied to the hydrogen cold system having no flow resistance in a moderator transfer tube, the system pressure rises by evaporation of liquid hydrogen. Then the boiling point of hydrogen rises. The liquefaction capacity of the condenser is increasing with a rise of temperature, because a refrigerating power of the helium refrigerator increases linearly with temperature rise of the system. Therefore, the effect of thermal heat load increase is compensated and cancelled out. The closed thermo-siphon has this feature generally, when the moderator transfer tube is designed to be no flow resistance. The report reviews the concept of self-regulation, and how to design and construct the cold neutron source with self-regulation. (author)

  8. Event generators for address event representation transmitters

    Science.gov (United States)

    Serrano-Gotarredona, Rafael; Serrano-Gotarredona, Teresa; Linares Barranco, Bernabe

    2005-06-01

    Address Event Representation (AER) is an emergent neuromorphic interchip communication protocol that allows for real-time virtual massive connectivity between huge number neurons located on different chips. By exploiting high speed digital communication circuits (with nano-seconds timings), synaptic neural connections can be time multiplexed, while neural activity signals (with mili-seconds timings) are sampled at low frequencies. Also, neurons generate 'events' according to their activity levels. More active neurons generate more events per unit time, and access the interchip communication channel more frequently, while neurons with low activity consume less communication bandwidth. In a typical AER transmitter chip, there is an array of neurons that generate events. They send events to a peripheral circuitry (let's call it "AER Generator") that transforms those events to neurons coordinates (addresses) which are put sequentially on an interchip high speed digital bus. This bus includes a parallel multi-bit address word plus a Rqst (request) and Ack (acknowledge) handshaking signals for asynchronous data exchange. There have been two main approaches published in the literature for implementing such "AER Generator" circuits. They differ on the way of handling event collisions coming from the array of neurons. One approach is based on detecting and discarding collisions, while the other incorporates arbitration for sequencing colliding events . The first approach is supposed to be simpler and faster, while the second is able to handle much higher event traffic. In this article we will concentrate on the second arbiter-based approach. Boahen has been publishing several techniques for implementing and improving the arbiter based approach. Originally, he proposed an arbitration squeme by rows, followed by a column arbitration. In this scheme, while one neuron was selected by the arbiters to transmit his event out of the chip, the rest of neurons in the array were

  9. Case report of cold-weather-induced radiation recall dermatitis after chemoradiotherapy with cisplatin

    International Nuclear Information System (INIS)

    Kindts, Isabelle; Stellamans, Karin; Planckaert, Nikie; Goethals, Laurence; Bonny, Michiel

    2014-01-01

    The radiation recall reaction (RRR) is an inflammatory reaction that occurs in previously irradiated areas. The phenomenon is probably due to an idiosyncratic hypersensitivity reaction, in which a second agent can recall the inflammatory reaction. This case report documents a cold-weather-induced radiation recall dermatitis (RRD). We observed a severe RRD in a patient after chemoradiotherapy treatment with cisplatin for a nasopharyngeal carcinoma, precipitated by cold temperatures, which developed 9 days after completion of therapy. In the medical literature, RRD following extreme cold temperatures seems to be a peculiar event. Until further information on the interaction is available, future studies on combined chemotherapy with cisplatin should be carefully monitored and any side effects clearly documented. This case suggests that environmental conditions may play a contributing role in the development of RRD. This case also implies that neither fraction size nor total radiation dose is a determining factor in the development of the dermatologic reaction. (orig.) [de

  10. Event-by-event jet quenching

    Energy Technology Data Exchange (ETDEWEB)

    Fries, R.J.; Rodriguez, R.; Ramirez, E.

    2010-08-14

    High momentum jets and hadrons can be used as probes for the quark gluon plasma (QGP) formed in nuclear collisions at high energies. We investigate the influence of fluctuations in the fireball on jet quenching observables by comparing propagation of light quarks and gluons through averaged, smooth QGP fireballs with event-by-event jet quenching using realistic inhomogeneous fireballs. We find that the transverse momentum and impact parameter dependence of the nuclear modification factor R{sub AA} can be fit well in an event-by-event quenching scenario within experimental errors. However the transport coefficient {cflx q} extracted from fits to the measured nuclear modification factor R{sub AA} in averaged fireballs underestimates the value from event-by-event calculations by up to 50%. On the other hand, after adjusting {cflx q} to fit R{sub AA} in the event-by-event analysis we find residual deviations in the azimuthal asymmetry v{sub 2} and in two-particle correlations, that provide a possible faint signature for a spatial tomography of the fireball. We discuss a correlation function that is a measure for spatial inhomogeneities in a collision and can be constrained from data.

  11. Event-by-event jet quenching

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, R. [Cyclotron Institute and Physics Department, Texas A and M University, College Station, TX 77843 (United States); Fries, R.J., E-mail: rjfries@comp.tamu.ed [Cyclotron Institute and Physics Department, Texas A and M University, College Station, TX 77843 (United States); RIKEN/BNL Research Center, Brookhaven National Laboratory, Upton, NY 11973 (United States); Ramirez, E. [Physics Department, University of Texas El Paso, El Paso, TX 79968 (United States)

    2010-09-27

    High momentum jets and hadrons can be used as probes for the quark gluon plasma (QGP) formed in nuclear collisions at high energies. We investigate the influence of fluctuations in the fireball on jet quenching observables by comparing propagation of light quarks and gluons through averaged, smooth QGP fireballs with event-by-event jet quenching using realistic inhomogeneous fireballs. We find that the transverse momentum and impact parameter dependence of the nuclear modification factor R{sub AA} can be fit well in an event-by-event quenching scenario within experimental errors. However the transport coefficient q extracted from fits to the measured nuclear modification factor R{sub AA} in averaged fireballs underestimates the value from event-by-event calculations by up to 50%. On the other hand, after adjusting q to fit R{sub AA} in the event-by-event analysis we find residual deviations in the azimuthal asymmetry v{sub 2} and in two-particle correlations, that provide a possible faint signature for a spatial tomography of the fireball. We discuss a correlation function that is a measure for spatial inhomogeneities in a collision and can be constrained from data.

  12. Event-by-event fluctuations at SPS

    CERN Document Server

    Appelshauser, Harald; Adamova, D.; Agakichiev, G.; Belaga, V.; Braun-Munzinger, P.; Castillo, A.; Cherlin, A.; Damjanovic, S.; Dietel, T.; Dietrich, L.; Drees, A.; Esumi, S.I.; Filimonov, K.; Fomenko, K.; Fraenkel, Z.; Garabatos, C.; Glassel, P.; Hering, G.; Holeczek, J.; Kushpil, V.; Lenkeit, B.; Ludolphs, W.; Maas, A.; Marn, A.; Milosevic, J.; Milov, A.; Miskowiec, D.; Panebrattsev, Yu.; Petchenova, O.; Petracek, V.; Pfeiffer, A.; Rak, J.; Ravinovich, I.; Rehak, P.; Schmitz, W.; Schukraft, J.; Sedykh, S.; Shimansky, S.; Slvova, J.; Stachel, J.; Sumbera, M.; Tilsner, H.; Tserruya, Itzhak; Wessels, J.P.; Wienold, T.; Windelband, B.; Wurm, J.P.; Xie, W.; Yurevich, S.; Yurevich, V.; Appelshauser, Harald; Sako, Hiro

    2005-01-01

    Results on event-by-event fluctuations of the mean transverse momentum and net charge in Pb-Au collisions, measured by the CERES Collaboration at CERN-SPS, are presented. We discuss the centrality and beam energy dependence and compare our data to cascade calculations.

  13. Cold Episodes, Their Precursors and Teleconnections in the Central Peruvian Andes (1958-2009)

    Science.gov (United States)

    Sulca, J. C.; Vuille, M. F.; Trasmonte, G.; Silva, Y.; Takahashi, K.

    2014-12-01

    The Mantaro valley (MV) is located in the central Peruvian Andes. Occasionally, cold episodes are observed during the austral summer (January-March), which strongly damage crops. However, little is known about the causes and impacts of such cold episodes in the MV. The main goal of this study is thus to characterize cold episodes in the MV and assess their large-scale circulation and teleconnections over South America (SA) during austral summer. To identify cold events in the MV daily minimum temperature for the period 1958-2009 from Huayao station, located within the MV was used. We defined a cold episode as the period when daily minimum temperature drops below the 10-percentile for at least one day. Several gridded reanalysis and satellite products were used to characterize the large-scale circulation, cloud cover and rainfall over SA associated with these events for same period. Cold episodes in the MV are associated with positive OLR anomalies, which extend over much of the central Andes, indicating reduced convective cloud cover during these extremes, but also affirm the large-scale nature of these events. At the same time, northeastern Brazil (NEB) registers negative OLR anomalies, strong convective activity and enhanced cloud cover because displacement of the South Atlantic Convergence Zone (SACZ) toward the northeast of its climatologic position. Further, it is associated with a weakening of the Bolivian High - Nordeste Low (BH-NL) system at upper levels, but also influenced by a low-level migratory high-pressure center develops at 30°S, 50°W; propagating from mid- to low latitudes as part of an extratropical Rossby wave train. In conclusion, cold episodes in the MV appear to be caused by radiative cooling associated with reduced cloudiness, rather than cold air advection. The reduced cloud cover in turn results from a robust large-scale pattern of westerly wind anomalies over central Peruvian Andes, inhibiting moisture influx, convective activity and

  14. Heat shock protection against cold stress of Drosophila melanogaster

    OpenAIRE

    Burton, Vicky; Mitchell, Herschel K.; Young, Patricia; Petersen, Nancy S.

    1988-01-01

    Heat shock protein synthesis can be induced during recovery from cold treatment of Drosophila melanogaster larvae. Survival of larvae after a cold treatment is dramatically improved by a mild heat shock just before the cold shock. The conditions which induce tolerance to cold are similar to those which confer tolerance to heat.

  15. Is freezing in the vaccine cold chain an ongoing issue? A literature review.

    Science.gov (United States)

    Hanson, Celina M; George, Anupa M; Sawadogo, Adama; Schreiber, Benjamin

    2017-04-19

    Vaccine exposure to temperatures below recommended ranges in the cold chain may decrease vaccine potency of freeze-sensitive vaccines leading to a loss of vaccine investments and potentially places children at risk of contracting vaccine preventable illnesses. This literature review is an update to one previously published in 2007 (Matthias et al., 2007), analyzing the prevalence of vaccine exposure to temperatures below recommendations throughout various segments of the cold chain. Overall, 45 studies included in this review assess temperature monitoring, of which 29 specifically assess 'too cold' temperatures. The storage segments alone were evaluated in 41 articles, 15 articles examined the transport segment and 4 studied outreach sessions. The sample size of the studies varied, ranging from one to 103 shipments and from three to 440 storage units. Among reviewed articles, the percentage of vaccine exposure to temperatures below recommended ranges during storage was 33% in wealthier countries and 37.1% in lower income countries. Vaccine exposure to temperatures below recommended ranges occurred during shipments in 38% of studies from higher income countries and 19.3% in lower income countries. This review highlights continuing issues of vaccine exposure to temperatures below recommended ranges during various segments of the cold chain. Studies monitoring the number of events vaccines are exposed to 'too cold' temperatures as well as the duration of these events are needed. Many reviewed studies emphasize the lack of knowledge of health workers regarding freeze damage of vaccines and how this has an effect on temperature monitoring. It is important to address this issue by educating vaccinators and cold chain staff to improve temperature maintenance and supply chain management, which will facilitate the distribution of potent vaccines to children. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  16. Asymptomatic myocardial ischemia following cold provocation

    International Nuclear Information System (INIS)

    Shea, M.J.; Deanfield, J.E.; deLandsheere, C.M.; Wilson, R.A.; Kensett, M.; Selwyn, A.P.

    1987-01-01

    Cold is thought to provoke angina in patients with coronary disease either by an increase in myocardial demand or an increase in coronary vascular resistance. We investigated and compared the effects of cold pressor stimulation and symptom-limited supine bicycle exercise on regional myocardial perfusion in 35 patients with stable angina and coronary disease and in 10 normal subjects. Regional myocardial perfusion was assessed with positron emission tomography and rubidium-82. Following cold pressor stimulation 24 of 35 patients demonstrated significant abnormalities of regional myocardial perfusion with reduced cation uptake in affected regions of myocardium: 52 +/- 9 to 43 +/- 9 (p less than 0.001 vs normal subjects). Among these 24 patients only nine developed ST depression and only seven had angina. In contrast, 29 of 35 patients underwent supine exercise, and abnormal regional myocardial perfusion occurred in all 29, with a reduction in cation intake from 48 +/- 10 to 43 +/- 14 (p less than 0.001 vs normal subjects). Angina was present in 27 of 29 and ST depression in 25 of 29. Although the absolute decrease in cation uptake was somewhat greater following cold as opposed to exercise, the peak heart rate after cold was significantly lower than that after exercise (82 +/- 12 vs 108 +/- 16 bpm, p less than 0.05). Peak systolic blood pressures after cold and exercise were similar (159 +/- 24 vs 158 +/- 28). Thus, cold produces much more frequent asymptomatic disturbances of regional myocardial perfusion in patients with stable angina and coronary disease than is suggested by pain or ECG changes

  17. Episodes, events, and models

    Directory of Open Access Journals (Sweden)

    Sangeet eKhemlani

    2015-10-01

    Full Text Available We describe a novel computational theory of how individuals segment perceptual information into representations of events. The theory is inspired by recent findings in the cognitive science and cognitive neuroscience of event segmentation. In line with recent theories, it holds that online event segmentation is automatic, and that event segmentation yields mental simulations of events. But it posits two novel principles as well: first, discrete episodic markers track perceptual and conceptual changes, and can be retrieved to construct event models. Second, the process of retrieving and reconstructing those episodic markers is constrained and prioritized. We describe a computational implementation of the theory, as well as a robotic extension of the theory that demonstrates the processes of online event segmentation and event model construction. The theory is the first unified computational account of event segmentation and temporal inference. We conclude by demonstrating now neuroimaging data can constrain and inspire the construction of process-level theories of human reasoning.

  18. Research on corrosion aspects of the advanced cold process canister

    International Nuclear Information System (INIS)

    Blackwood, D.J.; Hoch, A.R.; Naish, C.C.; Rance, A.

    1994-01-01

    The Advanced Cold Process Canister (ACPC) is a waste canister being developed jointly by SKB and TVO for the disposal of spent nuclear fuel. It comprises an outer copper canister, with a carbon steel canister inside. A concern regarding the use of the ACPC is that, in the unlikely event that the outer copper canister is penetrated, the anaerobic corrosion of the carbon steel container may result in the formation of hydrogen gas bubbles. These bubbles could disrupt the backfill, and thus increase water flow through the near field and the flux of radionuclides to the host geology. A number of factors that influence the rate at which hydrogen evolves as a result of the anaerobic corrosion of carbon steel in artificial granitic groundwaters have been investigated. A previously observed, time-dependent decline in the hydrogen evolution rate has been confirmed as being due to the production of magnetite film. Once the magnetite film is about 0.7-1.0 μm thick, the rate of hydrogen evolution reaches a steady state value. The pH and the ionic strength of the groundwater were both found to influence the long-term hydrogen evolution rate. The results of the experimental programme were used to update a model of the corrosion behaviour and hydrogen production from the Advanced Cold Process Canister. 36 figs, 5 tabs, 13 refs

  19. Cold-Hearted or Cool-Headed: Physical Coldness Promotes Utilitarian Moral Judgment

    Directory of Open Access Journals (Sweden)

    Hiroko eNakamura

    2014-10-01

    Full Text Available In the current study, we examine the effect of physical coldness on personal moral dilemma judgment. Previous studies have indicated that utilitarian moral judgment—sacrificing a few people to achieve the greater good for others—was facilitated when: (1 participants suppressed an initial emotional response and deliberately thought about the utility of outcomes; (2 participants had a high-level construal mindset and focused on abstract goals (e.g., save many; or (3 there was a decreasing emotional response to sacrificing a few. In two experiments, we exposed participants to extreme cold or typical room temperature and then asked them to make personal moral dilemma judgments. The results of Experiment 1 indicated that coldness prompted utilitarian judgment, but the effect of coldness was independent from deliberate thought or abstract high-level construal mindset. As Experiment 2 revealed, coldness facilitated utilitarian judgment via reduced empathic feelings. Therefore, physical coldness did not affect the cool-headed deliberate process or the abstract high-level construal mindset. Rather, coldness biased people toward being cold-hearted, reduced empathetic concern about a sacrificed victim, and facilitated utilitarian moral judgments.

  20. Cold War Paradigms and the Post-Cold War High School History Curriculum.

    Science.gov (United States)

    McAninch, Stuart A.

    1995-01-01

    Discusses how Cold War ideological models provide a way to examine the U.S. role in world affairs. Discusses and compares on the writings of Paul Gagnon and Noam Chomsky on this topic. Concludes that students should stand outside both models to develop a meaningful perspective on the U.S. role during the Cold War. (CFR)

  1. Cold recovery during regasification of LNG part one: Cold utilization far from the regasification facility

    International Nuclear Information System (INIS)

    La Rocca, Vincenzo

    2010-01-01

    The paper deals with cold recovery during LNG regasification. The applications analyzed pertain to the use in deep freezing agro food industry and in space air conditioning facilities in commercial sector (Supermarkets and Hypermarkets) of cold recovered from the regasification process. A modular LNG regasification unit is proposed having the regasification capacity of 2 BCM/year of gas and it is based on use of a Power Cycle working with Ethane, this unit allows operation of cold energy transfer, contained in LNG to be regasified, in a range of temperatures suitable for multipurpose use of cold, reducing regasification process irreversibility. Some electric energy is produced by the Power Cycle, but the purpose of the modular unit is to deliver cold suitable for industrial and commercial use in the proper temperature range utilizing Carbon dioxide as secondary fluid to transfer cold from regasification site to far end users. The subject is divided in two papers: this paper deals with facilities delivering cold released during LNG regasification and related pipeline facilities to transfer cold at far end users while the other paper pertains to analysis of end users applications. Results of a detailed thermodynamic and economic analysis demonstrate the suitability of the proposal.

  2. Cold Hole Over Jupiter's Pole

    Science.gov (United States)

    2002-01-01

    Observations with two NASA telescopes show that Jupiter has an arctic polar vortex similar to a vortex over Earth's Antarctica that enables depletion of Earth's stratospheric ozone.These composite images of Jupiter's north polar region from the Hubble Space Telescope (right) and the Infrared Telescope Facility (left) show a quasi-hexagonal shape that extends vertically from the stratosphere down into the top of the troposphere. A sharp temperature drop, compared to surrounding air masses, creates an eastward wind that tends to keep the polar atmosphere, including the stratospheric haze, isolated from the rest of the atmosphere.The linear striations in the composite projections are artifacts of the image processing. The area closest to the pole has been omitted because it was too close to the edge of the planet in the original images to represent the planet reliably.The composite on the right combines images from the Wide Field and Planetary Camera 2 of the Hubble Space Telescope taken at a wavelength of 890 nanometers, which shows stratospheric haze particles.The sharp boundary and wave-like structure of the haze layer suggest a polar vortex and a similarity to Earth's stratospheric polar clouds. Images of Jupiter's thermal radiation clinch that identification. The composite on the left, for example, is made from images taken with Jet Propulsion Laboratory's Mid-Infrared Large-Well Imager at NASA's Infrared Telescope Facility at a wavelength of 17 microns. It shows polar air mass that is 5 to 6 degrees Celsius (9 to 10 degrees Fahrenheit) colder than its surroundings, with the same border as the stratospheric haze. Similar observations at other infrared wavelengths show the cold air mass extends at least as high as the middle stratosphere down to the top of the troposphere.These images were taken Aug. 11 through Aug. 13, 1999, near a time when Jupiter's north pole was most visible from Earth. Other Infrared Telescope Facility images at frequencies sensitive to the

  3. Habituation of the cold shock response is inhibited by repeated anxiety: Implications for safety behaviour on accidental cold water immersions.

    Science.gov (United States)

    Barwood, Martin J; Corbett, Jo; Tipton, Mike; Wagstaff, Christopher; Massey, Heather

    2017-05-15

    Accidental cold-water immersion (CWI) triggers the life-threatening cold shock response (CSR) which is a precursor to sudden death on immersion. One practical means of reducing the CSR is to induce an habituation by undergoing repeated short CWIs. Habituation of the CSR is known to be partially reversed by the concomitant experience of acute anxiety, raising the possibility that repeated anxiety could prevent CSR habituation; we tested this hypothesis. Sixteen participants (12 male, 4 female) completed seven, seven-minute immersions in to cold water (15°C). Immersion one acted as a control (CON1). During immersions two to five, which would ordinarily induce an habituation, anxiety levels were repeatedly increased (CWI-ANX rep ) by deception and a demanding mathematical task. Immersions six and seven were counter-balanced with another high anxiety condition (CWI-ANX rep ) or a further control (CON2). Anxiety (20cm visual analogue scale) and cardiorespiratory responses (cardiac frequency [f c ], respiratory frequency [f R ], tidal volume [V T ], minute ventilation [V̇ E ]) were measured. Comparisons were made between experimental immersions (CON1, final CWI-ANX rep , CON2), across habituation immersions and with data from a previous study. Anxiety levels were sustained at a similar level throughout the experimental and habituation immersions (mean [SD] CON1: 7.0 [4.0] cm; CON2: 5.8 [5.2] cm cf CWI-ANX rep : 7.3 [5.5] cm; p>0.05). This culminated in failure of the CSR to habituate even when anxiety levels were not manipulated (i.e. CON2). These data were different (pCSR consequently habituated. Repeated anxiety prevented CSR habituation. A protective strategy that includes inducing habituation for those at risk should include techniques to lower anxiety associated with the immersion event or habituation may not be beneficial in the emergency scenario. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Forecasting European cold waves based on subsampling strategies of CMIP5 and Euro-CORDEX ensembles

    Science.gov (United States)

    Cordero-Llana, Laura; Braconnot, Pascale; Vautard, Robert; Vrac, Mathieu; Jezequel, Aglae

    2016-04-01

    Forecasting future extreme events under the present changing climate represents a difficult task. Currently there are a large number of ensembles of simulations for climate projections that take in account different models and scenarios. However, there is a need for reducing the size of the ensemble to make the interpretation of these simulations more manageable for impact studies or climate risk assessment. This can be achieved by developing subsampling strategies to identify a limited number of simulations that best represent the ensemble. In this study, cold waves are chosen to test different approaches for subsampling available simulations. The definition of cold waves depends on the criteria used, but they are generally defined using a minimum temperature threshold, the duration of the cold spell as well as their geographical extend. These climate indicators are not universal, highlighting the difficulty of directly comparing different studies. As part of the of the CLIPC European project, we use daily surface temperature data obtained from CMIP5 outputs as well as Euro-CORDEX simulations to predict future cold waves events in Europe. From these simulations a clustering method is applied to minimise the number of ensembles required. Furthermore, we analyse the different uncertainties that arise from the different model characteristics and definitions of climate indicators. Finally, we will test if the same subsampling strategy can be used for different climate indicators. This will facilitate the use of the subsampling results for a wide number of impact assessment studies.

  5. Dynamics of Charged Events

    International Nuclear Information System (INIS)

    Bachas, Constantin; Bunster, Claudio; Henneaux, Marc

    2009-01-01

    In three spacetime dimensions the world volume of a magnetic source is a single point, an event. We make the event dynamical by regarding it as the imprint of a flux-carrying particle impinging from an extra dimension. This can be generalized to higher spacetime dimensions and to extended events. We exhibit universal observable consequences of the existence of events and argue that events are as important as particles or branes. We explain how events arise on the world volume of membranes in M theory, and in a Josephson junction in superconductivity.

  6. The global event system

    International Nuclear Information System (INIS)

    Winans, J.

    1994-01-01

    The support for the global event system has been designed to allow an application developer to control the APS event generator and receiver boards. This is done by the use of four new record types. These records are customized and are only supported by the device support modules for the APS event generator and receiver boards. The use of the global event system and its associated records should not be confused with the vanilla EPICS events and the associated event records. They are very different

  7. Random and externally controlled occurrences of Dansgaard–Oeschger events

    Directory of Open Access Journals (Sweden)

    J. Lohmann

    2018-05-01

    Full Text Available Dansgaard–Oeschger (DO events constitute the most pronounced mode of centennial to millennial climate variability of the last glacial period. Since their discovery, many decades of research have been devoted to understand the origin and nature of these rapid climate shifts. In recent years, a number of studies have appeared that report emergence of DO-type variability in fully coupled general circulation models via different mechanisms. These mechanisms result in the occurrence of DO events at varying degrees of regularity, ranging from periodic to random. When examining the full sequence of DO events as captured in the North Greenland Ice Core Project (NGRIP ice core record, one can observe high irregularity in the timing of individual events at any stage within the last glacial period. In addition to the prevailing irregularity, certain properties of the DO event sequence, such as the average event frequency or the relative distribution of cold versus warm periods, appear to be changing throughout the glacial. By using statistical hypothesis tests on simple event models, we investigate whether the observed event sequence may have been generated by stationary random processes or rather was strongly modulated by external factors. We find that the sequence of DO warming events is consistent with a stationary random process, whereas dividing the event sequence into warming and cooling events leads to inconsistency with two independent event processes. As we include external forcing, we find a particularly good fit to the observed DO sequence in a model where the average residence time in warm periods are controlled by global ice volume and cold periods by boreal summer insolation.

  8. Random and externally controlled occurrences of Dansgaard-Oeschger events

    Science.gov (United States)

    Lohmann, Johannes; Ditlevsen, Peter D.

    2018-05-01

    Dansgaard-Oeschger (DO) events constitute the most pronounced mode of centennial to millennial climate variability of the last glacial period. Since their discovery, many decades of research have been devoted to understand the origin and nature of these rapid climate shifts. In recent years, a number of studies have appeared that report emergence of DO-type variability in fully coupled general circulation models via different mechanisms. These mechanisms result in the occurrence of DO events at varying degrees of regularity, ranging from periodic to random. When examining the full sequence of DO events as captured in the North Greenland Ice Core Project (NGRIP) ice core record, one can observe high irregularity in the timing of individual events at any stage within the last glacial period. In addition to the prevailing irregularity, certain properties of the DO event sequence, such as the average event frequency or the relative distribution of cold versus warm periods, appear to be changing throughout the glacial. By using statistical hypothesis tests on simple event models, we investigate whether the observed event sequence may have been generated by stationary random processes or rather was strongly modulated by external factors. We find that the sequence of DO warming events is consistent with a stationary random process, whereas dividing the event sequence into warming and cooling events leads to inconsistency with two independent event processes. As we include external forcing, we find a particularly good fit to the observed DO sequence in a model where the average residence time in warm periods are controlled by global ice volume and cold periods by boreal summer insolation.

  9. Autolysis of Pichia pastoris induced by cold.

    Science.gov (United States)

    Bartolo-Aguilar, Yaneth; Dendooven, Luc; Chávez-Cabrera, Cipriano; Flores-Cotera, Luis B; Hidalgo-Lara, María E; Villa-Tanaca, Lourdes; Marsch, Rodolfo

    2017-12-01

    The production of recombinant biopharmaceutical proteins is a multi-billion dollar market. Protein recovery represents a major part of the production costs. Pichia pastoris is one of the microbial systems most used for the production of heterologous proteins. The use of a cold-induced promoter to express lytic enzymes in the yeast after the growth stage could reduce protein recovery costs. This study shows that a cold-shock can be applied to induce lysis of the yeast cells. A strain of P. pastoris was constructed in which the endogenous eng gene encoding a putative endo-β-1,3-glucanase was overexpressed using the cold-shock induced promoter of the cctα gene from Saccharomyces cerevisiae. In the transgenic P. pastoris, the expression of eng increased 3.6-fold after chilling the cells from 30 to 4 °C (cold-shock stage) followed by incubation for 6 h (eng expression stage). The culture was heated to 30 °C for 6 h (ENG synthesis stage) and kept at 37 °C for 24 h (lysis stage). After this procedure the cell morphology changed, spheroplasts were obtained and cellular lysis was observed. Thus, a clone of P. pastoris was obtained, which undergoes autolysis after a cold-shock.

  10. Cold versus hot fusion deuterium branching ratios

    International Nuclear Information System (INIS)

    Fox, H.; Bass, R.

    1995-01-01

    A major source of misunderstanding of the nature of cold nuclear fusion has been the expectation that the deuterium branching ratios occurring within a palladium lattice would be consistent with the gas-plasma branching ratios. This misunderstanding has led to the concept of the dead graduate student, the 1989's feverish but fruitless search for neutron emissions from cold fusion reactors, and the follow-on condemnation of the new science of cold fusion. The experimental facts are that in a properly loaded palladium lattice, the deuterium fusion produces neutrons at little above background, a greatly less-than-expected production of tritium (the tritium desert), and substantially more helium-4 than is observed in hot plasma physics. The experimental evidence is now compelling (800 reports of success from 30 countries) that cold nuclear fusion is a reality, that the branching ratios are unexpected, and that a new science is struggling to be recognized. Commercialization of some types of cold fusion devices has already begun

  11. Metallization of Various Polymers by Cold Spray

    Science.gov (United States)

    Che, Hanqing; Chu, Xin; Vo, Phuong; Yue, Stephen

    2018-01-01

    Previous results have shown that metallic coatings can be successfully cold sprayed onto polymeric substrates. This paper studies the cold sprayability of various metal powders on different polymeric substrates. Five different substrates were used, including carbon fiber reinforced polymer (CFRP), acrylonitrile butadiene styrene (ABS), polyether ether ketone (PEEK), polyethylenimine (PEI); mild steel was also used as a benchmark substrate. The CFRP used in this work has a thermosetting matrix, and the ABS, PEEK and PEI are all thermoplastic polymers, with different glass transition temperatures as well as a number of distinct mechanical properties. Three metal powders, tin, copper and iron, were cold sprayed with both a low-pressure system and a high-pressure system at various conditions. In general, cold spray on the thermoplastic polymers rendered more positive results than the thermosetting polymers, due to the local thermal softening mechanism in the thermoplastics. Thick copper coatings were successfully deposited on PEEK and PEI. Based on the results, a method is proposed to determine the feasibility and deposition window of cold spraying specific metal powder/polymeric substrate combinations.

  12. PWR cold-leg small break loca with faulty HPI

    International Nuclear Information System (INIS)

    Kumamaru, H.; Kukita, Y.

    1991-01-01

    The ROSA-IV Large Scale Test Facility (LSTF) is a 1/48 volumetrically-scaled model of a pressurized water reactor (PWR). At the LSTF are performed cold-leg small-break loss-of-coolant accident (LOCA) tests with faulty high pressure injection (HPI) system for break areas from 0.5% to 10% and an intentional primary system depressurization test following a small-break LOCA test. A simple prediction model is proposed for prediction of times of major events. Test data and calculations show that intentional primary system depressurization with use of the pressurizer power-operated relief valves (PORVs) is effective for break areas of approximately 0.5% or less, is unnecessary for breaks of 5% or more, and is insufficient for intermediate break areas to maintain adequate core cooling. (author)

  13. Event by event physics in ALICE

    CERN Document Server

    Christakoglou, Panos

    2009-01-01

    Fluctuations of thermodynamic quantities are fundamental for the study of the QGP phase transition. The ALICE experiment is well suited for precise event-by-event measurements of various quantities. In this article, we review the capabilities of ALICE to study the fluctuations of several key observables such as the net charge, the temperature, and the particle ratios. Among the observables related to correlations, we review the balance functions and the long range correlations.

  14. PHYSIOLOGICAL AND LEUKOCYTE SUBSET RESPONSES TO EXERCISE AND COLD EXPOSURE IN COLD-ACCLIMATIZED SKATERS

    Directory of Open Access Journals (Sweden)

    K. Kim

    2014-07-01

    Full Text Available We investigated physiological responses and changes in circulating immune cells following exercise in cold and thermoneutral conditions. Participants were short track skaters (n=9 who were acclimatized to cold conditions, and inline skaters (n=10 who were not acclimatized. All skaters were young, and skating at a recreational level three days per week for at least one year. Using a cross-over design, study variables were measured during 60 min of submaximal cycling (65% ·VO2max in cold (ambient temperature: 5±1°C, relative humidity: 41±9% and thermoneutral conditions (ambient temperature: 21±1°C, relative humidity: 35±5%. Heart rate, blood lactate and tympanic temperature were measured at rest, during exercise and recovery. Plasma cortisol, calprotectin and circulating blood cell numbers were measured before and after 60 min of cold or thermoneutral conditions, and during recovery from exercise. Heart rate was lower in both groups during exercise in cold versus thermoneutral conditions (P<0.05. The increase in total leukocytes during recovery was primarily due to an increase in neutrophils in both groups. The cold-acclimatized group activated neutrophils after exercise in cold exposure, whereas the non-acclimatized group activated lymphocyte and cortisol after exercise in cold exposure. Lymphocyte subsets significantly changed in both groups over time during recovery as compared to rest. Immediately after exercise in both groups, CD16+ and CD69+ cells were elevated compared to rest or before exercise in both conditions. Acclimatization to exercise in the cold does not appear to influence exercise-induced immune changes in cold conditions, with the possible exception of neutrophils, lymphocytes and cortisol concentration.

  15. Conferences and Events

    International Development Research Centre (IDRC) Digital Library (Canada)

    André Lavoie

    2016-06-14

    Jun 14, 2016 ... Approved by the Management Executive Committee. - 1 - ... Event ‒ represents activities related to IDRC operations and may include both ... Events include business meetings; corporate, branch or divisional management.

  16. Initiating events frequency determination

    International Nuclear Information System (INIS)

    Simic, Z.; Mikulicic, V.; Vukovic, I.

    2004-01-01

    The paper describes work performed for the Nuclear Power Station (NPS). Work is related to the periodic initiating events frequency update for the Probabilistic Safety Assessment (PSA). Data for all relevant NPS initiating events (IE) were reviewed. The main focus was on events occurring during most recent operating history (i.e., last four years). The final IE frequencies were estimated by incorporating both NPS experience and nuclear industry experience. Each event was categorized according to NPS individual plant examination (IPE) initiating events grouping approach. For the majority of the IE groups, few, or no events have occurred at the NPS. For those IE groups with few or no NPS events, the final estimate was made by means of a Bayesian update with general nuclear industry values. Exceptions are rare loss-of-coolant-accidents (LOCA) events, where evaluation of engineering aspects is used in order to determine frequency.(author)

  17. Finishing of the cold mass assembly

    CERN Multimedia

    Patrice Loïez

    2001-01-01

    Photo 1 Technicians are putting in order the instrumentation wires. The prototype magnets were equipped with numerous sensors to monitor key parameters during the performance tests at cold conditions. Photo 2 The cold mass assembly is resting on special supports in order to allow the finishing operations. Technicians are putting in order the instrumentation wires. The prototype magnets were equipped with numerous sensors to monitor key parameters during the performance tests at cold conditions. Photo 3 View of the lyre-side end of the active part assembly. The extremity of the shrinking cylinder has been bevelled in view of welding the end cover. Photo 4 General view of the finishing station showing the special supporting structures (blue and yellow structures) needed for the geometric measurements and for the alignment operations. One can also see the light building surrounding the finishing station, which purpose is to isolate the laser measuring machines from disturbances. Photo 5 The extremity of the shri...

  18. Development of cold source moderator structure

    International Nuclear Information System (INIS)

    Aso, Tomokaze; Ishikura, Syuichi; Terada, Atsuhiko; Teshigawara, Makoto; Watanabe, Noboru; HIno, Ryutaro

    1999-01-01

    The cold and thermal neutrons generated at the target (which works as a spallation neutron source under a 5MW proton beam condition) is filtered with cold source moderators using supercritical hydrogen. Preliminary structural analysis was carried out to clarify technical problems on the concept of the thin-walled structure for the cold source moderator. Structural analytical results showed that the maximum stress of 1 12MPa occurred on the moderator surface, which exceeded the allowable design stresses of ordinary aluminum alloys. Flow patterns measured by water flow experiments agreed well with hydraulic analytical results, which showed that an impinging jet flow from an inner pipe of the moderator caused a recirculation flow on a large scale. Based on analytical and experimental results, new moderator structures with minute frames, blowing flow holes etc. were proposed to keep its strength and to suppress the recirculation flow. (author)

  19. Setting parameters in the cold chain

    Directory of Open Access Journals (Sweden)

    Victoria Rodríguez

    2011-12-01

    Full Text Available Breaks in the cold chain are important economic losses in food and pharmaceutical companies. Many of the failures in the cold chain are due to improper adjustment of equipment parameters such as setting the parameters for theoretical conditions, without a corresponding check in normal operation. The companies that transport refrigeratedproducts must be able to adjust the parameters of the equipment in an easy and quick to adapt their functioning to changing environmental conditions. This article presents the results of a study carried out with a food distribution company. The main objective of the study is to verify the effectiveness of Six Sigma as a methodological toolto adjust the equipment in the cold chain. The second objective is more speciÞ c and is to study the impact of: reducing the volume of storage in the truck, the initial temperature of the storage areain the truck and the frequency of defrost in the transport of refrigerated products.

  20. Sympathetic cooling of nanospheres with cold atoms

    Science.gov (United States)

    Montoya, Cris; Witherspoon, Apryl; Ranjit, Gambhir; Casey, Kirsten; Kitching, John; Geraci, Andrew

    2016-05-01

    Ground state cooling of mesoscopic mechanical structures could enable new hybrid quantum systems where mechanical oscillators act as transducers. Such systems could provide coupling between photons, spins and charges via phonons. It has recently been shown theoretically that optically trapped dielectric nanospheres could reach the ground state via sympathetic cooling with trapped cold atoms. This technique can be beneficial in cases where cryogenic operation of the oscillator is not practical. We describe experimental advances towards coupling an optically levitated dielectric nanosphere to a gas of cold Rubidium atoms. The sphere and the cold atoms are in separate vacuum chambers and are coupled using a one-dimensional optical lattice. This work is partially supported by NSF, Grant Nos. PHY-1205994,PHY-1506431.

  1. The quality of cold smoked salmon

    DEFF Research Database (Denmark)

    Løje, Hanne

    2007-01-01

    The objective of this Ph. D. thesis was to study the liquid holding capacity/liquid loss of raw and smoked salmonids as affected by raw material and chill storage of the cold smoked product. The liquid holding capacity is an important quality parameter for cold smoked salmon. This study has shown...... that the liquid holding capacity in raw and cold smoked salmon is influenced by several factors. The size of the fish affected the liquid holding capacity as large fish had lower liquid holding capacity than smaller fish. The salt content influenced the liquid holding capacity in smoked fish as it was found...... capacity in raw salmon, as high lipid content gave lower liquid holding capacity. Thus, the lipid content is an important parameter regarding the liquid holding capacity as it can influence the liquid holding capacity directly or indirectly by affecting other factors e.g. the salt content which influences...

  2. Gravitational waves in cold dark matter

    Science.gov (United States)

    Flauger, Raphael; Weinberg, Steven

    2018-06-01

    We study the effects of cold dark matter on the propagation of gravitational waves of astrophysical and primordial origin. We show that the dominant effect of cold dark matter on gravitational waves from astrophysical sources is a small frequency dependent modification of the propagation speed of gravitational waves. However, the magnitude of the effect is too small to be detected in the near future. We furthermore show that the spectrum of primordial gravitational waves in principle contains detailed information about the properties of dark matter. However, depending on the wavelength, the effects are either suppressed because the dark matter is highly nonrelativistic or because it contributes a small fraction of the energy density of the universe. As a consequence, the effects of cold dark matter on primordial gravitational waves in practice also appear too small to be detectable.

  3. Activation analysis opportunities using cold neutron beams

    Energy Technology Data Exchange (ETDEWEB)

    Lindstrom, R M; Zeisler, R; Rossbach, M

    1987-05-01

    Guided beams of cold neutrons being installed at a number of research reactors may become increasingly available for analytical research. A guided cold beam will provide higher neutron fluence rates and lower background interferences than in present facilities. In an optimized facility, fluence rates of 10/sup 9/ nxcm/sup -2/xs/sup -1/ are obtainable. Focusing a large area beam onto a small target will further increase the neutron intensity. In addition, the shift to lower neutron energy increases the effective cross sections. The absence of fast neutrons and gamma rays permits detectors to be placed near the sample without intolerable background, and thus the efficiency for counting prompt gamma rays can be much higher than in present systems. Measurements made at the hydrogen cold source of the FRJ-2 (DIDO) reactor at the KFA provide a numerical evaluation of the improvements in PGAA with respect to signal-to-background ratios of important elements and matrices. (author) 15 refs.

  4. 305 Building Cold Test Facility Management Plan

    International Nuclear Information System (INIS)

    Whitehurst, R.

    1994-01-01

    This document provides direction for the conduct of business in Building 305 for cold testing tools and equipment. The Cold Test Facility represents a small portion of the overall building, and as such, the work instructions already implemented in the 305 Building will be utilized. Specific to the Cold Test there are three phases for the tools and equipment as follows: 1. Development and feature tests of sludge/fuel characterization equipment, fuel containerization equipment, and sludge containerization equipment to be used in K-Basin. 2. Functional and acceptance tests of all like equipment to be installed and operated in K-Basin. 3. Training and qualification of K-Basin Operators on equipment to be installed and operated in the Basin

  5. The cold neutron source in DR 3

    International Nuclear Information System (INIS)

    Jensen, K.; Leth, j.A.

    1980-09-01

    A description of the cold neutron source in DR 3 is given. The moderator of the cold neutron source is supercritical hydrogen at about 30degK and 15 bar abs. The necessary cooling capacity is supplied by two Philips Stirling B20 cryogenerators. The hydrogen is circulated between the cryogenerators and the in-pile moderator chamber by small fans. The safety of the facility is based on the use of triple containment preventing contact between hydrogen and air. The triple containment is achieved by enclosing the high vacuum system, surrounging the hydrogen system, in a helium blanket. The achieved spectrum of the thermal neutron flux and the gain factor are given as well as the experience from more than 5 years of operation. Finally some work on extension of the facility to operate two cold sources is reported. (author)

  6. Sodium hydride precipitation in sodium cold traps

    International Nuclear Information System (INIS)

    McPheeters, C.C.; Raue, D.J.

    1979-10-01

    A series of experiments have been performed to test a calculational model for precipitation of NaH in sodium cold traps. The calculational model, called ACTMODEL, is a computer simulation that uses the system geometry and operating conditions as input to calculate a mass transfer coefficient and the distribution of NaH in a cold trap. The ACTMODEL was tested using an analytical cold trap (ACT) that is simple and essentially one-dimensional. The ACT flow and temperature profile may be controlled at any desired condition. The ACT was analyzed destructively after each test to measure the actual NaH distribution. Excellent agreement was obtained between the ACTMODEL simulations and the experiments

  7. Sodium hydride precipitation in sodium cold traps

    International Nuclear Information System (INIS)

    McPheeters, C.C.; Raue, D.J.

    1980-06-01

    A series of experiments have been performed to test a calculational model for precipitation of NaH in sodium cold traps. The calculational model, called ACTMODEL, is a computer simulation that uses the system geometry and operating conditions as input to calculate a mass-transfer coefficient and the distribution of NaH in a cold trap. The ACTMODEL was tested using an analytical cold trap (ACT) that is simple and essentially one-dimensional. The ACT flow and temperature profile can be controlled at any desired condition. The ACT was analyzed destructively after each test to measure the actual NaH distribution. Excellent agreement was obtained between the ACTMODEL simulations and the experiments. Mass-transfer coefficients ranging upward from 6 x 10 -5 m/s were measured in both packless and packed traps. As much as a fourfold increase in precipitation surface area was observed with increasing amount of NaH deposited. 11 figures, 2 tables

  8. Advertising Effectiveness In Events

    OpenAIRE

    Jain, Sushilkumar

    2012-01-01

    Confronted with decreasing effectiveness of the classic marketing communications, events have become an increasingly popular alternative for marketers. Events constitute one of the most exciting and fastest growing forms of leisure and business. With time, the decreasing effectiveness of classical marketing communications boosted the use of events for marketing and making brand awareness. Event marketing is seen as the unique opportunity to integrate the firm’s communication activities like p...

  9. Overexpression of a peach CBF gene in apple: a model for understanding the integration of growth, dormancy, and cold hardiness in woody plants

    Science.gov (United States)

    The timing of cold acclimation and de-acclimation, dormancy, and bud break play an integral role in the life cycle of woody plants. The molecular events that regulate these parameters have been the subject of much study, however, in most studies these events have been investigated independently of ...

  10. Multimodal distribution of human cold pain thresholds.

    Science.gov (United States)

    Lötsch, Jörn; Dimova, Violeta; Lieb, Isabel; Zimmermann, Michael; Oertel, Bruno G; Ultsch, Alfred

    2015-01-01

    It is assumed that different pain phenotypes are based on varying molecular pathomechanisms. Distinct ion channels seem to be associated with the perception of cold pain, in particular TRPM8 and TRPA1 have been highlighted previously. The present study analyzed the distribution of cold pain thresholds with focus at describing the multimodality based on the hypothesis that it reflects a contribution of distinct ion channels. Cold pain thresholds (CPT) were available from 329 healthy volunteers (aged 18 - 37 years; 159 men) enrolled in previous studies. The distribution of the pooled and log-transformed threshold data was described using a kernel density estimation (Pareto Density Estimation (PDE)) and subsequently, the log data was modeled as a mixture of Gaussian distributions using the expectation maximization (EM) algorithm to optimize the fit. CPTs were clearly multi-modally distributed. Fitting a Gaussian Mixture Model (GMM) to the log-transformed threshold data revealed that the best fit is obtained when applying a three-model distribution pattern. The modes of the identified three Gaussian distributions, retransformed from the log domain to the mean stimulation temperatures at which the subjects had indicated pain thresholds, were obtained at 23.7 °C, 13.2 °C and 1.5 °C for Gaussian #1, #2 and #3, respectively. The localization of the first and second Gaussians was interpreted as reflecting the contribution of two different cold sensors. From the calculated localization of the modes of the first two Gaussians, the hypothesis of an involvement of TRPM8, sensing temperatures from 25 - 24 °C, and TRPA1, sensing cold from 17 °C can be derived. In that case, subjects belonging to either Gaussian would possess a dominance of the one or the other receptor at the skin area where the cold stimuli had been applied. The findings therefore support a suitability of complex analytical approaches to detect mechanistically determined patterns from pain phenotype data.

  11. Conceptual design of HANARO cold neutron source

    International Nuclear Information System (INIS)

    Lee, Chang Hee; Sim, Cheul Muu; Park, K. N.; Choi, Y. H.

    2002-07-01

    The purpose of the cold source is to increase the available neutron flux delivered to instruments at wavelength 4 ∼ 12 A. The major engineering targets of this CNS facility is established for a reach out of very high gain factors in consideration with the cold neutron flux, moderator, circulation loop, heat load, a simplicity of the maintenance of the facility, safety in the operation of the facility against the hydrogen explosion and a layout of a minimum physical interference with the present facilities. The cold source project has been divided into 5 phases: (1) pre-conceptual (2) conceptual design (3) Testing (4) detailed design and procurement (5) installation and operation. Although there is sometime overlap between the phases, in general, they are sequential. The pre-conceptual design and concept design of KCNS has been performed on elaborations of PNPI Russia and review by Technicatome, Air Liquid, CILAS France. In the design of cold neutron source, the characteristics of cold moderators have been studied to obtain the maximum gain of cold neutron, and the analysis for radiation heat, design of hydrogen system, vacuum system and helium system have been performed. The possibility for materialization of the concept in the proposed conceptual design has been reviewed in view of securing safety and installing at HANARO. Above all, the thermosiphon system to remove heat by circulation of sub-cooled two phase hydrogen has been selected so that the whole device could be installed in the reactor pool with the reduced volume. In order to secure safety, hydrogen safety has been considered on protection to prevent from hydrogen-oxygen reaction at explosion of hydrogen-oxygen e in the containment. A lay out of the installation, a maintenance and quality assurance program and a localization are included in this report. Requirements of user, regulatory, safety, operation, maintenance should be considered to be revised for detailed design, testing, installation

  12. A Mosque event

    DEFF Research Database (Denmark)

    Simonsen, Kirsten; Neergaard, Maja de; Koefoed, Lasse Martin

    2017-01-01

    and public imaginations attached to it. And they are connected to a specific event – the opening of the mosque. In the first part, a conceptual framework is presented bringing together literature on three notions: encounters, visibility and the event. Following this, the paper explores the opening event...

  13. On semirecurrent events

    International Nuclear Information System (INIS)

    Dvurechenskij, A.

    1984-01-01

    In some problems of the mathematical theory of particle counters, film or filmless measurements of track ionization in high energy physics,queueing theory, random walks, etc., the classes of emirecurrent and m-semirecurrent events, which generalize the recurrent events and the recurrent events with delay, appeared. In the paper their basic properties, and some relationships between them are shown

  14. Sterile Neutrinos in Cold Climates

    International Nuclear Information System (INIS)

    Jones, Benjamin J.P.

    2015-01-01

    Measurements of neutrino oscillations at short baselines contain an intriguing set of experimental anomalies that may be suggestive of new physics such as the existence of sterile neutrinos. This three-part thesis presents research directed towards understanding these anomalies and searching for sterile neutrino oscillations. Part I contains a theoretical discussion of neutrino coherence properties. The open-quantum-system picture of neutrino beams, which allows a rigorous prediction of coherence distances for accelerator neutrinos, is presented. Validity of the standard treatment of active and sterile neutrino oscillations at short baselines is verified, and non-standard coherence loss effects at longer baselines are predicted. Part II concerns liquid argon detector development for the MicroBooNE experiment, which will search for short-baseline oscillations in the Booster Neutrino Beam at Fermilab. Topics include characterization and installation of the MicroBooNE optical system; test-stand measurements of liquid argon optical properties with dissolved impurities; optimization of wavelength-shifting coatings for liquid argon scintillation light detection; testing and deployment of high-voltage surge arrestors to protect TPC field cages; and software development for optical and TPC simulation and reconstruction. Part III presents a search for sterile neutrinos using the IceCube neutrino telescope, which has collected a large sample of atmospheric-neutrino-induced events in the 1-10 TeV energy range. Sterile neutrinos would modify the detected neutrino flux shape via MSW-resonant oscillations. Following a careful treatment of systematic uncertainties in the sample, no evidence for MSW-resonant oscillations is observed, and exclusion limits on 3+1 model parameter space are derived. Under the mixing assumptions made, the 90% confidence level exclusion limit extends to sin 2 2θ 24 ≤ 0.02 at m 2 ~ 0.3 eV 2 , and the LSND and MiniBooNE allowed regions are excluded at

  15. A novel behavioral assay for measuring cold sensation in mice.

    Directory of Open Access Journals (Sweden)

    Daniel S Brenner

    Full Text Available Behavioral models of cold responses are important tools for exploring the molecular mechanisms of cold sensation. To complement the currently cold behavioral assays and allow further studies of these mechanisms, we have developed a new technique to measure the cold response threshold, the cold plantar assay. In this assay, animals are acclimated on a glass plate and a cold stimulus is applied to the hindpaw through the glass using a pellet of compressed dry ice. The latency to withdrawal from the cooled glass is used as a measure of the cold response threshold of the rodents, and the dry ice pellet provides a ramping cold stimulus on the glass that allows the correlation of withdrawal latency values to rough estimates of the cold response threshold temperature. The assay is highly sensitive to manipulations including morphine-induced analgesia, Complete Freund's Adjuvant-induced inflammatory allodynia, and Spinal Nerve Ligation-induced neuropathic allodynia.

  16. A novel behavioral assay for measuring cold sensation in mice.

    Science.gov (United States)

    Brenner, Daniel S; Golden, Judith P; Gereau, Robert W

    2012-01-01

    Behavioral models of cold responses are important tools for exploring the molecular mechanisms of cold sensation. To complement the currently cold behavioral assays and allow further studies of these mechanisms, we have developed a new technique to measure the cold response threshold, the cold plantar assay. In this assay, animals are acclimated on a glass plate and a cold stimulus is applied to the hindpaw through the glass using a pellet of compressed dry ice. The latency to withdrawal from the cooled glass is used as a measure of the cold response threshold of the rodents, and the dry ice pellet provides a ramping cold stimulus on the glass that allows the correlation of withdrawal latency values to rough estimates of the cold response threshold temperature. The assay is highly sensitive to manipulations including morphine-induced analgesia, Complete Freund's Adjuvant-induced inflammatory allodynia, and Spinal Nerve Ligation-induced neuropathic allodynia.

  17. Cold temperatures increase cold hardiness in the next generation Ophraella communa beetles.

    Directory of Open Access Journals (Sweden)

    Zhong-Shi Zhou

    Full Text Available The leaf beetle, Ophraella communa, has been introduced to control the spread of the common ragweed, Ambrosia artemisiifolia, in China. We hypothesized that the beetle, to be able to track host-range expansion into colder climates, can phenotypically adapt to cold temperatures across generations. Therefore, we questioned whether parental experience of colder temperatures increases cold tolerance of the progeny. Specifically, we studied the demography, including development, fecundity, and survival, as well as physiological traits, including supercooling point (SCP, water content, and glycerol content of O. communa progeny whose parents were maintained at different temperature regimes. Overall, the entire immature stage decreased survival of about 0.2%-4.2% when parents experienced cold temperatures compared to control individuals obtained from parents raised at room temperature. However, intrinsic capacity for increase (r, net reproductive rate (R 0 and finite rate of increase (λ of progeny O. communa were maximum when parents experienced cold temperatures. Glycerol contents of both female and male in progeny was significantly higher when maternal and paternal adults were cold acclimated as compared to other treatments. This resulted in the supercooling point of the progeny adults being significantly lower compared to beetles emerging from parents that experienced room temperatures. These results suggest that cold hardiness of O. communa can be promoted by cold acclimation in previous generation, and it might counter-balance reduced survival in the next generation, especially when insects are tracking their host-plants into colder climates.

  18. Moisture sources of the Mono Lake deglacial pluvial events

    Science.gov (United States)

    Wang, X.; Liang, M. C.; Ali, G.; Shen, C. C.; Cai, Y.; Ke, L.; Hemming, S. R.

    2016-12-01

    Enormously expanded lakes existed in the today's dry western US Great Basin during the last glacial period. The ancient shorelines located well above modern lake levels suggest that precipitation in lake basins must have been substantially higher in the past. It is however under debate whether the subtropical North Pacific or the tropical Pacific is the major moisture source that contributed to the pluvial events, particularly during the deglaciation. Here, we collected a suite of tufa carbonate samples deposited at the 2,080 meter terrace ( 135 meters above today's lake level) in the Mono Basin, California, a closed lake basin for the last 130 thousand years (kyr). At Goat Ranch, we discovered white, shiny, laminated botryoidal carbonate coatings on tufa mounds. Most of these coatings present two generations of formation separated by a hiatus, which indicates lake level fluctuations. Using high-precision U-Th dating techniques, we found that the lower layer was formed 14.1-14.4 kyr BP (corresponding to the North Atlantic Bølling warming period). The upper layer of the coating was formed 11.9-12.3 kyr BP (within the Younger Dryas event). We then obtained d18O, d13C, D47 and 17O-excess values for the two carbonate layers. The upper part is characterized by low d18O values, -8 to -12 ‰ VPDB, whereas the lower one has higher d18O values, -5 to -6 ‰ VPDB. Both share similar d13C values ( 1-2‰ VPDB). D47 analysis on the carbonates suggests that both layers were deposited in a water temperature of 9±2 oC (1s, n = 4 and 8, respectively). The two generations of carbonates present 17O-excess of moisture in values of 50±5 (1s, n=4) and 25±5 (1s, n=8) per meg VSMOW-SLAP, respectively. The large difference in 17O-excess of parent meteoric water points to different origins of moisture for the tufa carbonate formations. The high 17O-excess values during YD suggest a moisture source with a low relative humidity, consistent with the conventional view that the moisture

  19. Sterile Neutrinos in Cold Climates

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Benjamin J.P. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)

    2015-09-01

    Measurements of neutrino oscillations at short baselines contain an intriguing set of experimental anomalies that may be suggestive of new physics such as the existence of sterile neutrinos. This three-part thesis presents research directed towards understanding these anomalies and searching for sterile neutrino oscillations. Part I contains a theoretical discussion of neutrino coherence properties. The open-quantum-system picture of neutrino beams, which allows a rigorous prediction of coherence distances for accelerator neutrinos, is presented. Validity of the standard treatment of active and sterile neutrino oscillations at short baselines is verified, and non-standard coherence loss effects at longer baselines are predicted. Part II concerns liquid argon detector development for the MicroBooNE experiment, which will search for short-baseline oscillations in the Booster Neutrino Beam at Fermilab. Topics include characterization and installation of the MicroBooNE optical system; test-stand measurements of liquid argon optical properties with dissolved impurities; optimization of wavelength-shifting coatings for liquid argon scintillation light detection; testing and deployment of high-voltage surge arrestors to protect TPC field cages; and software development for optical and TPC simulation and reconstruction. Part III presents a search for sterile neutrinos using the IceCube neutrino telescope, which has collected a large sample of atmospheric-neutrino-induced events in the 1-10 TeV energy range. Sterile neutrinos would modify the detected neutrino flux shape via MSW-resonant oscillations. Following a careful treatment of systematic uncertainties in the sample, no evidence for MSW-resonant oscillations is observed, and exclusion limits on 3+1 model parameter space are derived. Under the mixing assumptions made, the 90% confidence level exclusion limit extends to sin224 ≤ 0.02 at m2 ~ 0.3 eV2, and the LSND and Mini

  20. The process and risk of the CPR1000 cold function test in the cold area

    International Nuclear Information System (INIS)

    Liu Tinghao; Zhang Jian; Ji Dapeng; Shi Quanjian; Tian Kuo

    2014-01-01

    Hong yanhe nuclear power station is the first CPR1000 reactor which is under construction in the cold area of north China. It is also the first time to carry out the cold functional test (CFT) in the winter of north China. The preparation and process of CFT are described in the paper. According to the experience feedback of CFT of Unit 1, the risk and solution which are significance for the CFT of the other NPS in the cold area are analysed. (authors)

  1. Event-by-Event Observables and Fluctuations

    International Nuclear Information System (INIS)

    Petersen, Hannah

    2013-01-01

    In this talk the status and open questions of the phenomenological description of all the stages of a heavy ion reaction are highlighted. Special emphasis is put on event-by-event fluctuations and associated observables. The first part is concentrated on high RHIC and LHC energies and the second part reviews the challenges for modeling heavy ion reactions at lower beam energies in a more realistic fashion. Overall, the main conclusion is that sophisticated theoretical dynamical approaches that describe many observables in the same framework are essential for the quantitative understanding of the properties of hot and dense nuclear matter

  2. Effects of various intake valve timings and spark timings on combustion, cyclic THC and NOX emissions during cold start phase with idle operation in CVVT engine

    International Nuclear Information System (INIS)

    Choi, Kwan Hee; Lee, Hyung Min; Hwang, In Goo; Myung, Cha Lee; Park, Sim Soo

    2008-01-01

    In a gasoline SI engine, valve events and spark timings put forth a major influence on overall efficiency, fuel economy, and exhaust emissions. Residual gases controlled by the valve overlap can be used to reduce NOx emissions and the spark retardation technique can be used to improve raw THC emissions and catalyst light-off performance during the cold start phase. This paper investigated the behaviors of the engine and its combustion characteristics with various intake valve timings and spark timings during the fast idle condition and cold start. And cyclic THC and NOx emissions were measured at the exhaust port and their formation mechanisms were examined with fast response gas analyzers. As a result, THCs and NOx were reduced by 35% and 23% with optimizing valve overlap and spark advance during the cold transient start phase. Consequently, the valve events and ignition timings were found to significantly affect combustion phenomena and cold-start emissions

  3. Excited-state imaging of cold atoms

    NARCIS (Netherlands)

    Sheludko, D.V.; Bell, S.C.; Vredenbregt, E.J.D.; Scholten, R.E.; Deshmukh, P.C.; Chakraborty, P.; Williams, J.F.

    2007-01-01

    We have investigated state-selective diffraction contrast imaging (DCI) of cold 85Rb atoms in the first excited (52P3/2) state. Excited-state DCI requires knowledge of the complex refractive index of the atom cloud, which was calculated numerically using a semi-classical model. The Autler-Townes

  4. State-selective imaging of cold atoms

    NARCIS (Netherlands)

    Sheludko, D.V.; Bell, S.C.; Anderson, R.; Hofmann, C.S.; Vredenbregt, E.J.D.; Scholten, R.E.

    2008-01-01

    Atomic coherence phenomena are usually investigated using single beam techniques without spatial resolution. Here we demonstrate state-selective imaging of cold 85Rb atoms in a three-level ladder system, where the atomic refractive index is sensitive to the quantum coherence state of the atoms. We

  5. Cold water inlet in solar tanks - valuation

    DEFF Research Database (Denmark)

    Andersen, Elsa

    1999-01-01

    The aim of the project is to make a proposal for how to value a storage tank with a poor design of the cold water inlet. Based on measurements and calculations a number of curves, which are valid for this valuation, are worked out. Based on a simple test with a uniform heated storage tank the rat...

  6. Recent cold fusion claims: are they valid?

    International Nuclear Information System (INIS)

    Kowalski, Ludwik

    2006-01-01

    Cold fusion consists of nuclear reactions occurring in solid metals loaded with hydrogen. Considerable progress has been made in that area in the last ten years. This 2004 paper summarizes recent claims without attempting to evaluate their validity. The manuscript was submitted to seven physics journals. Unfortunately, the editors rejected it without the benefit of the usual peer-review process. (author)

  7. Caring devices: about warmth, coldness and 'fit'

    NARCIS (Netherlands)

    Pols, J.

    2010-01-01

    Healthcare technologies are often put in opposition to warm human care and contact. This paper explores the assumed coldness of medical technologies by presenting the case of a technology that is experienced as particularly caring by the patients using them. This is a device to support terminal

  8. Flange Curling in Cold Formed Profiles

    DEFF Research Database (Denmark)

    Jönsson, Jeppe; Ramonas, Gediminas

    2012-01-01

    The non-linear flange curling phenomenon in cold formed profiles is the tendency of slender flanges to deform towards the neutral axis for increasing flexural curvature. Based on Braziers work, Winter proposed a simple engineering formula for determination of the local flange deformation towards...

  9. Cold plasma: Quality control and regulatory considerations

    Science.gov (United States)

    In recent years, cold plasma has emerged as a promising antimicrobial treatment for fresh and fresh-cut produce, nuts, spices, seeds, and other foods. Research has demonstrated effective control of human pathogens such as Salmonella, Listeria monocytogenes, Escherichia coli O157:H7, norovirus, and o...

  10. Improved cold neutron radiographic apparatus and method

    International Nuclear Information System (INIS)

    1981-01-01

    An improved cold neutron radiography technique is described in which the neutron temperature is matched to the specific material to be analyzed. In addition to a beam source and detector the apparatus incorporates a cryogenic refrigerator which enables the moderator material to be cooled to a predetermined adjustable temperature below the Bragg edge temperature of the sample. (U.K.)

  11. Anisotropic Interactions between Cold Rydberg Atoms

    Science.gov (United States)

    2015-09-28

    AFRL-AFOSR-CL-TR-2015-0002 Anisotropic interactions between cold Rydberg atoms Luis Marcassa INSTITUTO DE FISICA DE SAO CARLOS Final Report 09/28...problem with the report +551633739806 Organization / Institution name Instituto de Fisica de Sao Carlos Grant/Contract Title The full title of the

  12. Cold Flows and Large Scale Tides

    NARCIS (Netherlands)

    Weygaert, R. van de; Hoffman, Y.

    1998-01-01

    Abstract: Several studies have indicated that the local cosmic velocity field is rather cold, in particular in the regions outside the massive, virialized clusters of galaxies. If our local cosmic environment is taken to be a representative volume of the Universe, the repercussion of this finding is

  13. Neutron measurements in search of cold fusion

    International Nuclear Information System (INIS)

    Anderson, R.E.; Goulding, C.A.; Johnson, M.W.; Butterfield, K.B.; Gottesfeld, S.; Baker, D.A.; Springer, T.E.; Garzon, F.H.; Bolton, R.D.; Leonard, E.M.; Chancellor, T.

    1990-01-01

    We have conducted a research for neutron emission from cold fusion systems of the electrochemical type and, to a lesser extent, the high-pressure gas cell type. Using a high-efficiency well counter and an NE 213 scintillator, the experiments were conducted on the earth's surface and in a shielded cave approximately 50 ft underground. After approximately 6500 h of counting time, we have obtained no evidence for cold fusion processes leading to neutron production. However, we have observed all three types of neutron data that have been presented as evidence for cold fusion: large positive fluctuations in the neutron counting rate, weak peaks near 2.5 MeV in the neutron energy spectrum, and bursts of up to 145 neutrons in 500-μs intervals. The data were obtained under circumstances that clearly show our results to be data encountered as a part of naturally occurring neutron background, which is due primarily to cosmic rays. Thus, observing these types of data does not, of itself, provide evidence for the existence of cold fusion processes. Artifacts in the data that were due to counter misbehavior were also to lead to long-term ''neutron bursts'' whose time duration varied from several hours to several days. We conclude that any experiments which attempt to observe neutron emission must include strong steps to ensure that the experiments deal adequately with both cosmic-ray processes and counter misbehavior. 13 refs., 14 figs

  14. Spiral modes in cold cylindrical systems

    International Nuclear Information System (INIS)

    Robe, H.

    1975-01-01

    The linearized hydrodynamical equations governing the non-axisymmetric free modes of oscillation of cold cylindrical stellar systems are separated in cylindrical coordinates and solved numerically for two models. Short-wavelength unstable modes corresponding to tight spirals do not exist; but there exists an unstable growing mode which has the form of trailing spirals which are quite open. (orig.) [de

  15. A possible candidate for cold dark matter

    Indian Academy of Sciences (India)

    This additional scalar can be a viable candidate of cold dark matter (CDM) since the stability of is achieved by the application of Z 2 symmetry on . Considering as a possible candidate of CDM, Boltzmann's equation is solved to find the freeze-out temperature and relic density of for Higgs mass 120 GeV in the scalar ...

  16. Photoassociation of cold metastable helium atoms

    NARCIS (Netherlands)

    Woestenenk, G.R.

    2001-01-01

    During the last decades the study of cold atoms has grown in a great measure. Research in this field has been made possible due to the development of laser cooling and trapping techniques. We use laser cooling to cool helium atoms down to a temperature of 1 mK and we are able to

  17. Surface Plasmon Polaritons Probed with Cold Atoms

    DEFF Research Database (Denmark)

    Kawalec, Tomasz; Sierant, Aleksandra; Panas, Roman

    2017-01-01

    We report on an optical mirror for cold rubidium atoms based on a repulsive dipole potential created by means of a modified recordable digital versatile disc. Using the mirror, we have determined the absolute value of the surface plasmon polariton (SPP) intensity, reaching 90 times the intensity...

  18. Manual Performance Deterioration in the Cold

    NARCIS (Netherlands)

    Daanen, H.A.M.

    2009-01-01

    Manual performance during military operations in cold and windy climates is severely hampered by decreased dexterity, but valid dexterity decrease predictors based on climatic factors are scarce. Therefore, this study investigated the decrease in finger dexterity for nine combinations of ambient

  19. Some theories of cold nuclear fusion

    International Nuclear Information System (INIS)

    Preparata, G.

    1991-01-01

    In this paper a review is presented of the main theoretical attempts to describe the phenomenology of cold fusion, whose general structure begins to clearly unravel. The main conclusion is that the approaches that are likely to be of relevance must invoke processes where the elementary components (nuclei and electrons) of condensed matter act in a coherent fashion

  20. [Managing the cold chain in healthcare facilities].

    Science.gov (United States)

    Royer, Mathilde; Breton Marchand, Justine; Pons, David

    2017-11-01

    The storage of temperature-sensitive healthcare products requires control of the cold chain. Healthcare facilities must have the appropriate equipment at their disposal and ensure the traceability and monitoring of temperatures. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  1. Angular distribution in ternary cold fission

    International Nuclear Information System (INIS)

    Delion, D.S.; J.W. Goethe Univ., Frankfurt; Sandulescu, A.; J.W. Goethe Univ., Frankfurt; Greiner, W.

    2003-01-01

    We describe the spontaneous ternary cold fission of 252 Cf, accompanied by 4 He, 10 Be and 14 C. The light cluster decays from the first resonant eigenstate in the Coulomb potential plus a harmonic oscillator potential. We have shown that the angular distribution of the emitted light particle is strongly connected with its deformation and the equatorial distance. (author)

  2. Finishing of the cold mass assembly

    CERN Multimedia

    Maximilien Brice

    2001-01-01

    Photo 1 General view of the finishing station showing the special supporting structures (blue and yellow structures) needed for the geometric measurements and for the alignment operations. Around the magnet, there are datum points (on the tripodes) needed to build up the coordinates system for the measurements. Photo 2 The corrector magnets that are sextupoles are prepared for a plug-in fixation on their mechanical support. Photo 3 A corretor magnet has been installed on the left cold bore tube. The second one is waiting on the table for installation. Photo 4 The mechanical mole holding the corner cube reflector of the 3-D measuring machine is introduced in the cold bore tube (the right one on the picture). This will allow to pick up the X-Y-Z coordinates of the centre of the cold bore tube on its entire length. Photo 5 This picture shows the driving system that is completely computer controlled to pull the mechanical mole inside the cold bore tube. Photo 6 This picture shows details of the driving system...

  3. Cold - an underrated risk factor for health

    International Nuclear Information System (INIS)

    Mercer, James B.

    2003-01-01

    Cardiovascular diseases (CVD) are responsible for around 20% of all deaths worldwide (approximately 14 million) and are the principal cause of death in all developed countries, accounting for 50% of all deaths. Variations in the annual per capita death rates in different countries are well documented. Less well known are seasonal variations in death rates, with the highest levels occurring during the colder winter months, which have been described in many countries. This phenomenon is referred to as excess winter mortality. CVD-related deaths account for the majority of excess winter deaths (up to 70% in some countries), while about half of the remaining are due to increases in respiratory diseases. Paradoxically, CVD mortality increases to a greater extent with a given fall in temperature in regions with warm winters. While much of the indirect evidence points to the notion that cold is somehow involved in explaining excess winter deaths, the mechanism by which seemingly mild exposure to cold ambient conditions can increase the risk of death remains unclear. The strong indirect epidemiological evidence coupling cold climate to mortality may be related to indoor rather than outdoor climatic conditions (e.g., cold/damp houses versus arm/dry houses) coupled with a plethora of factors including health status, ageing-related deterioration in physiological and behavioral thermoregulation, toxicology, and socioeconomic factors

  4. Cold-crucible fabrication of nuclear glasses

    International Nuclear Information System (INIS)

    Boen, R.

    2010-01-01

    Vitrification has stood the nuclear industry in good stead, for many years now, as a safe long-term conditioning technology for high-level waste. Major advances are nonetheless still being made, with the development of the cold-crucible technology, affording as it does new possibilities, in terms of volume reduction, and of extending the range of waste products amenable to incorporation. Indeed, by allowing higher melting temperatures to be achieved (1200 - 1400 C degrees), this process opens the way to a considerable increase in glass production capacities, and the fabrication of novel matrices, involving higher incorporation rates than current glasses. In the cold-crucible technology, materials put into the crucible are heated directly through induction. The crucible made of metal is cooled by water circulation. Where the glass comes into contact with the cold wall, a thin layer of solidified glass forms, with a thickness of 5-10 mm preventing the metal forming the crucible from coming into contact with the molten glass. A full scale pilot of the cold crucible was constructed at the La Hague vitrification workshop

  5. Condensation of galactic cold dark matter

    International Nuclear Information System (INIS)

    Visinelli, Luca

    2016-01-01

    We consider the steady-state regime describing the density profile of a dark matter halo, if dark matter is treated as a Bose-Einstein condensate. We first solve the fluid equation for “canonical” cold dark matter, obtaining a class of density profiles which includes the Navarro-Frenk-White profile, and which diverge at the halo core. We then solve numerically the equation obtained when an additional “quantum pressure” term is included in the computation of the density profile. The solution to this latter case is finite at the halo core, possibly avoiding the “cuspy halo problem” present in some cold dark matter theories. Within the model proposed, we predict the mass of the cold dark matter particle to be of the order of M_χc"2≈10"−"2"4 eV, which is of the same order of magnitude as that predicted in ultra-light scalar cold dark matter models. Finally, we derive the differential equation describing perturbations in the density and the pressure of the dark matter fluid.

  6. Basic physics with ultra cold neutrons

    International Nuclear Information System (INIS)

    Protasov, K.

    2007-01-01

    A short introduction to the physics of Ultra Cold Neutrons (UCN) is given. It covers different aspects from their discovery, their major properties as well as their using in the three experiments of fundamental physics: measurements of the neutron life time and of its electric dipole moment and studies of neutrons quantum states in the Earth's gravitational field. (author)

  7. On solitary surface waves in cold plasmas

    International Nuclear Information System (INIS)

    Vladimirov, S.V.; Yu, M.Y.; Stenflo, L.

    1993-01-01

    A new type of nonlinear electromagnetic solitary surface waves propagating along the boundary of a cold plasma is discussed. These waves are described by a novel nonlinear evolution equation, obtained when the nonlinear surface currents at the boundary are taken into consideration. (Author)

  8. Educational Exchange as a Cold War Weapon

    DEFF Research Database (Denmark)

    Rasmussen, Anders Bo

    2014-01-01

    American President Harry S. Truman called the Cold War a "struggle for the minds of men," and assigned journalists an important role in the conflict. This study finds that the U.S. Depeartment of State, via the American Embassy in Copenhagen, consciously attempted to shape Danish journalits' view...

  9. Viscoelastic behaviour of cold recycled asphalt mixes

    Science.gov (United States)

    Cizkova, Zuzana; Suda, Jan

    2017-09-01

    Behaviour of cold recycled mixes depends strongly on both the bituminous binder content (bituminous emulsion or foamed bitumen) and the hydraulic binder content (usually cement). In the case of cold recycled mixes rich in bitumen and with low hydraulic binder content, behaviour is close to the viscoelastic behaviour of traditional hot mix asphalt. With decreasing bituminous binder content together with increasing hydraulic binder content, mixes are characteristic with brittle behaviour, typical for concrete pavements or hydraulically bound layers. The behaviour of cold recycled mixes with low content of both types of binders is similar to behaviour of unbound materials. This paper is dedicated to analysing of the viscoelastic behaviour of the cold recycled mixes. Therefore, the tested mixes contained higher amount of the bituminous binder (both foamed bitumen and bituminous emulsion). The best way to characterize any viscoelastic material in a wide range of temperatures and frequencies is through the master curves. This paper includes interesting findings concerning the dependency of both parts of the complex modulus (elastic and viscous) on the testing frequency (which simulates the speed of heavy traffic passing) and on the testing temperature (which simulates the changing climate conditions a real pavement is subjected to).

  10. Laser-Free Cold-Atom Gymnastics

    Science.gov (United States)

    Gould, Harvey; Feinberg, Benedict; Munger, Charles T., Jr.; Nishimura, Hiroshi

    2017-01-01

    We have performed beam transport simulations on ultra cold (2 μK) and cold (130 μK) neutral Cs atoms in the F = M = + 4 (magnetic weak-field seeking) ground state. We use inhomogeneous magnetic fields to focus and accelerate the atoms. Acceleration of neutral atoms by an inhomogeneous magnetic field was demonstrated by Stern and Gerlach in 1922. In the simulations, a two mm diameter cloud of atoms is released to fall under gravity. A magnetic coil focuses the falling atoms. After falling 41 cm, the atoms are reflected in the magnetic fringe field of a solenoid. They return to their starting height, about 0.7 s later, having passed a second time through the focusing coil. The simulations show that > 98 % of ultra cold Cs atoms and > 70 % of cold Cs atoms will survive at least 15 round trips (assuming perfect vacuum). More than 100 simulations were run to optimize coil currents and focusing coil diameter and height. Simulations also show that atoms can be launched into a fountain. An experimental apparatus to test the simulations, is being constructed. This technique may find application in atomic fountain clocks, interferometers, and gravitometers, and may be adaptable for use in microgravity. It may also work with Bose-Einstein condensates of paramagnetic atoms.

  11. Draught Risk from Cold Vertical Surfaces

    DEFF Research Database (Denmark)

    Heiselberg, Per

    Glazed facades and atria have had a boom in the 1980's as an architectural feature in building design. Natural convective flows from these cold surfaces are in winter time, however, often the cause of thermal discomfort and there is a need for research to improve the design methods. The objective...

  12. Superheavy nuclei – cold synthesis and structure

    Indian Academy of Sciences (India)

    120 and Ж = 172 or 184, for superheavy nuclei. This result is discussed in ... 1980 [7] on the basis of the QMFT, once again prior to its observation in 1984. Thus, cold ... On the other hand, based on a rather complete deformed relativistic mean field (DRMF) calculation, using the NL1 parameter set, we [16] predicted. = 120.

  13. Effects of cold temperatures on the excitability of rat trigeminal ganglion neurons that are not for cold-sensing

    Science.gov (United States)

    Kanda, Hirosato; Gu, Jianguo G.

    2016-01-01

    Except a small population of primary afferent neurons for sensing cold to generate the sensations of innocuous and noxious cold, it is generally believed that cold temperatures suppress the excitability of other primary afferent neurons that are not for cold-sensing. These not-for-cold-sensing neurons include the majority of non-nociceptive and nociceptive afferent neurons. In the present study we have found that not-for-cold-sensing neurons of rat trigeminal ganglia (TG) change their excitability in several ways at cooling temperatures. In nearly 70% of not-for-cold-sensing TG neurons, the cooling temperature of 15°C increases their membrane excitability. We regard these neurons as cold-active neurons. For the remaining 30% of not-for-cold-sensing TG neurons, the cooling temperature of 15°C either has no effect (regarded as cold-ineffective neurons) or suppress (regarded as cold-suppressive neurons) their membrane excitability. For cold-active neurons, the cold temperature of 15°C increases their excitability as is evidenced by the increases in action potential (AP) firing numbers and/or reduction of AP rheobase when these neurons are depolarized electrically. The cold temperature of 15°C significantly inhibits M-currents and increases membrane input resistance of cold-active neurons. Retigabine, an M-current activator, abolishes the effect of cold temperatures on AP firing but not the effect of cold temperature on AP rheobase levels. The inhibition of M-currents and the increases of membrane input resistance are likely two mechanisms by which cooling temperatures increase the excitability of not-for-cold-sensing TG neurons. PMID:26709732

  14. Nuclear Waste Vitrification Efficiency: Cold Cap Reactions

    International Nuclear Information System (INIS)

    Kruger, A.A.; Hrma, P.R.; Pokorny, R.

    2011-01-01

    The cost and schedule of nuclear waste treatment and immobilization are greatly affected by the rate of glass production. Various factors influence the performance of a waste-glass melter. One of the most significant, and also one of the least understood, is the process of batch melting. Studies are being conducted to gain fundamental understanding of the batch reactions, particularly those that influence the rate of melting, and models are being developed to link batch makeup and melter operation to the melting rate. Batch melting takes place within the cold cap, i.e., a batch layer floating on the surface of molten glass. The conversion of batch to glass consists of various chemical reactions, phase transitions, and diffusion-controlled processes. These include water evaporation (slurry feed contains as high as 60% water), gas evolution, the melting of salts, the formation of borate melt, reactions of borate melt with molten salts and with amorphous oxides (Fe 2 O 3 and Al 2 O 3 ), the formation of intermediate crystalline phases, the formation of a continuous glass-forming melt, the growth and collapse of primary foam, and the dissolution of residual solids. To this list we also need to add the formation of secondary foam that originates from molten glass but accumulates on the bottom of the cold cap. This study presents relevant data obtained for a high-level-waste melter feed and introduces a one-dimensional (1D) mathematical model of the cold cap as a step toward an advanced three-dimensional (3D) version for a complete model of the waste glass melter. The 1D model describes the batch-to-glass conversion within the cold cap as it progresses in a vertical direction. With constitutive equations and key parameters based on measured data, and simplified boundary conditions on the cold-cap interfaces with the glass melt and the plenum space of the melter, the model provides sensitivity analysis of the response of the cold cap to the batch makeup and melter

  15. Window of cold nuclear fusion and biased-pulse electrolysis experiment

    International Nuclear Information System (INIS)

    Takahashi, Akito; Jida, Toshiyuki; Maekawa, Fujio; Sugimoto, Hisashi; Yoshida, Shigeo

    1989-01-01

    Based on the electron screening effect and the excitation of deuteron harmonic oscillators in palladium lattice, theoretical aspects are given to explain the cold fusion phenomena and the possibility of nuclear heating. A narrow window is proposed to meet ≅ 10 watts per cubic centimeter for the nuclear heating, by the hypothetical excitation-screening model. A relatively wide window is feasible to meet a few fusion events per second per cc under the non-stationary conditions of deuteron-charging and discharging. For stationary lattice conditions, the probability of cold fusion is not feasible at all. To confirm the cold fusion phenomena, a heavy water electrolysis experiment was carried out using biased-pulse-electrolytic currents, expecting the enhancement of cold fusion events under charging and discharging of deuterons. For the neutron detection, a cross-checking system between a recoil-proton scintillation detector and a 3 He thermal neutron detector was employed to see coincident time-patterns of neutron emission from an electrolysis cell. To check the energy of emitted neutrons, pulse height spectrum of the recoil-proton detector was monitored. Up to the D-charging time of 300 hr, neutron yields of 1-2 n/s/cc were obtained for time-intervals of 60-200 hr. From the recoil-proton spectra, it was confirmed that 2.45 MeV neutrons by the D(d, n) 3 He fusion branch were emitted. The observed time-patterns of neutron emission suggest the existence of cold fusion under the charging and discharging conditions. (orig.)

  16. A case study in experiential learning: pharmaceutical cold chain management on wheels.

    Science.gov (United States)

    Vesper, James; Kartoglu, Ümit; Bishara, Rafik; Reeves, Thomas

    2010-01-01

    People who handle and regulate temperature-sensitive pharmaceutical products require the knowledge and skills to ensure those products maintain quality, integrity, safety, and efficacy throughout their shelf life. People best acquire such knowledge and skills through "experiential learning" that involves working with other learners and experts. The World Health Organization developed a weeklong experiential learning event for participants so they could gain experience in how temperature-sensitive products are handled, stored, and distributed throughout the length of the distribution supply chain system. This experiential learning method enabled participants to visit, critically observe, discuss and report on the various components of the cold chain process. An emphasis was placed on team members working together to learn from one another and on several global expert mentors who were available to guide the learning, share their experiences, and respond to questions. The learning event, Pharmaceutical Cold Chain Management on Wheels, has been conducted once each year since 2008 in Turkey with participants from the global pharmaceutical industry, health care providers, national regulatory authorities, and suppliers/vendors. Observations made during the course showed that it was consistent with the principles of experiential and social learning theories. Questionnaires and focus groups provided evidence of the value of the learning event and ways to improve it. Reflecting the critical elements derived from experiential and social learning theories, five factors contributed to the success of this unique experiential learning event. These factors may also have relevance in other experiential learning courses and, potentially, for experiential e-learning events.

  17. Identifying jet quantum numbers event by event

    International Nuclear Information System (INIS)

    Teper, M.J.

    1979-12-01

    A method is proposed to identify the parton that gives rise to any particular jet. The method improves with the number of particles in the jet, and should indicate which of the jets in a three jet event at PETRA is the gluon jet. (author)

  18. Vitrification of HLW in cold crucible melter

    International Nuclear Information System (INIS)

    Bordier, G.

    2005-01-01

    The performance of the vitrification process currently used in the La Hague commercial reprocessing plants has been continuously improved during more than ten years of operation. In parallel the CEA (French Atomic Energy Commission), COGEMA (Industrial Operator), and SGN (COGEMA's Engineering) have developed the cold crucible melter vitrification technology to obtain greater operating flexibility, increased plant availability and further reduction of secondary waste generated during operations. The cold crucible is a compact water-cooled melter in which the radioactive waste and the glass additives are melted by direct high frequency induction. The cooling of the melter produces a solidified glass layer that protects the melter's inner wall from corrosion. Because the heat is transferred directly to the melt, high operating temperatures can be achieved with no impact on the melter itself. COGEMA plans to implement the cold crucible technology to vitrify high level liquid waste from reprocessed spent U-Mo-Sn-Al fuel (used in gas cooled reactor). The cold crucible was selected for the vitrification of this particularly hard-to-process waste stream because it could not be reasonably processed in the standard hot induction melters currently used at the La Hague vitrification facilities: the waste has a high molybdenum content which makes it very corrosive and also requires a special high temperature glass formulation to obtain sufficiently high waste loading factors (12 % in molybdenum). A special glass formulation has been developed by the CEA and has been qualified through lab and pilot testing to meet standard waste acceptance criteria for final disposal of the U-Mo waste. The process and the associated technologies have been also qualified on a full-scale prototype at the CEA pilot facility in Marcoule. Engineering study has been integrated in parallel in order to take into account that the Cold Crucible should be installed remotely in one of the R7 vitrification

  19. Cold urticaria: inhibition of cold-induced histamine release by doxantrazole.

    Science.gov (United States)

    Bentley-Phillips, C B; Eady, R A; Greaves, M W

    1978-10-01

    Thirteen patients with cold urticaria were studied to assess the effect of the systemic drug doxantrazole, which has actions resembling disodium cromoglycate, on cold evoked histamine release. The patients, all of whom developed an immediate local whealing response after cooling of the forearm, demonstrated release of histamine into venous blood draining that forearm. Following doxantrazole treatment, significant suppression of histamine release occurred. In some but not all patients this was accompanied by diminution of urtication in response to cooling. A double-blind study was carried out in 3 subjects, all of whom showed diminished cold-stimulated histamine release after doxantrazole. Two of these showed clinical improvement. Doxantrazole had no effect on erythema due to intradermal histamine, but did suppress the erythematous reaction to intradermal injection of compound 48/80. Our results suggest that doxantrazole or related anti-allergic agents might be useful in the treatment of cold urticaria.

  20. Cold neutron interferometry and its application. 2. Coherency and cold neutron spin interferometry

    International Nuclear Information System (INIS)

    Achiwa, Norio; Ebisawa, Toru

    1998-03-01

    The second workshop entitled 'Interference studies and cold neutron spin interferometry' was held on 10 and 11 March 1998 at KUR (Kyoto University Research Reactor Institute, Kumatori). Cold neutron spin interferometry is a new field. So it is very important for its development to learn the studies of X-ray and neutron optics which are rapidly developing with long history. In the workshop, the issues related to interference were reviewed such as experimental studies on cold neutron spin interferometry, theoretical and experimental approach on tunneling time, interference experiments by neutrons and its application, interference studies using synchrotron radiation, topics on silicon interferometry and quantum measurement problem and cold neutron interference experiment related to quantum measurement problem. The 8 of the presented papers are indexed individually. (J.P.N.)

  1. Development and application of the european cold chain database as a tool for cold chain management

    OpenAIRE

    Gogou , E.; Katsaros , G.; Derens , E.; Li , L.; Alvarez , G.; Taoukis , P.

    2013-01-01

    2nd IIR International Conference on Sustainability and the Cold Chain, Paris, FRA, 02-/04/2013 - 04/04/2013; International audience; Storage and distribution are the weakest links in the food management. Their effective control is important for their commercial viability, since they often deviate from specifications. FRISBEE (http://frisbee - project.eu) is a Food Refrigeration Innovation for Cold Chain research IP European project. Within FRISBEE a web - based platform (hosted in the link ht...

  2. Chlorophyll fluorescence emission can screen cold tolerance of cold acclimated Arabidopsis thaliana accessions

    Czech Academy of Sciences Publication Activity Database

    Mishra, Anamika; Heyer, A. G.; Mishra, Kumud

    2014-01-01

    Roč. 10, č. 38 (2014) ISSN 1746-4811 R&D Projects: GA MŠk EE2.3.20.0246; GA MŠk 7E12047 Institutional support: RVO:67179843 Keywords : high-throughput screening * chlorophyll a fluorescence transients * cold tolerance * cold acclimation * whole plant * Arabidopsis thaliana Subject RIV: EH - Ecology, Behaviour Impact factor: 3.102, year: 2014

  3. Soundscapes, events, resistance

    Directory of Open Access Journals (Sweden)

    Andrea Mubi Brighenti

    2008-12-01

    Full Text Available Put it bluntly, a soundscape is the sonic counterpart, or component, of landscape. From such minimal assumption, some interesting consequences follow: just as landscape is far from being a simple stage-set upon which events take place, soundscape, too, is itself evental, i.e., it consists of events. Not only because its nature, far from being acoustics is always ‘psychoacoustics’, as Murray Schafer (1977/1994 first argued. Processes of environmental perception are of course there.

  4. Cisgenic inhibition of the potato cold induced phosphorylase L gene ...

    African Journals Online (AJOL)

    transgenic line M4), implying that silencing of starch phosphorylase L gene reduced starch breakdown during cold storage conditions. Key words: Cold sweetening, potato (Solanum tuberosum L.), RNA interference, starch phosphorylase L. gene, ...

  5. Cold stratification, but not stratification in salinity, enhances seedling ...

    African Journals Online (AJOL)

    use

    2011-10-26

    Oct 26, 2011 ... Cold stratification was reported to release seed dormancy and enhance plant tolerance to salt stress. ... Key words: Cold stratification, salt stress, seedling emergence, ... methods used to cope with salinity, seed pre-sowing.

  6. Training to Fight Training and Education During the Cold War

    National Research Council Canada - National Science Library

    Winkler, David

    1997-01-01

    ... requirements of military missions." One of Legacy's nine task areas is the Cold War Project, which seeks to "inventory, protect, and conserve DoD's physical and literary property and relics" associated with the Cold War. In early 1993, Dr...

  7. Cold, Flu, or Allergy? Know the Difference for Best Treatment

    Science.gov (United States)

    ... October 2014 Print this issue Cold, Flu, or Allergy? Know the Difference for Best Treatment En español ... Peanut Allergy Therapy Wise Choices Cold, Flu, or Allergy? Treatment depends on which you have. A health ...

  8. Development of Cold Neutron Activation Station at HANARO Cold Neutron Source

    International Nuclear Information System (INIS)

    Sun, G. M.; Hoang, S. M. T.; Moon, J. H.; Chung, Y. S.; Cho, S. J.; Lee, K. H.; Park, B. G.; Choi, H. D.

    2012-01-01

    A new cold neutron source at the HANARO Research Reactor had been constructed in the framework of a five-year project, and ended in 2009. It has seven neutron guides, among which five guides were already allocated for a number of neutron scattering instruments. A new two-year project to develop a Cold Neutron Activation Station (CONAS) was carried out at the two neutron guides since May 2010, which was supported by the program of the Ministry of Education, Science and Technology, Korea. Fig. 1 shows the location of CONAS. CONAS is a complex facility including several radioanalytical instruments utilizing neutron capture reaction to analyze elements in a sample. It was designed to include three instruments like a CN-PGAA (Cold Neutron - Prompt Gamma Activation Analysis), a CN-NIPS (Cold Neutron - Neutron Induced Pair Spectrometer), and a CN-NDP (Cold Neutron - Neutron-induced prompt charged particle Depth Profiling). Fig. 2 shows the conceptual configuration of the CONAS concrete bioshield and the instruments. CN-PGAA and CN-NIPS measure the gamma-rays promptly emitted from the sample after neutron capture, whereas CN-NDP is a probe to measure the charged particles emitted from the sample surface after neutron capture. For this, we constructed two cold neutron guides called CG1 and CG2B guides from the CNS

  9. An empirical model for friction in cold forging

    DEFF Research Database (Denmark)

    Bay, Niels; Eriksen, Morten; Tan, Xincai

    2002-01-01

    With a system of simulative tribology tests for cold forging the friction stress for aluminum, steel and stainless steel provided with typical lubricants for cold forging has been determined for varying normal pressure, surface expansion, sliding length and tool/work piece interface temperature...... of normal pressure and tool/work piece interface temperature. The model is verified by process testing measuring friction at varying reductions in cold forward rod extrusion. KEY WORDS: empirical friction model, cold forging, simulative friction tests....

  10. Cold Storage for a Single-Family House in Italy

    OpenAIRE

    Luigi Mongibello; Giorgio Graditi

    2016-01-01

    This work deals with the operation, modeling, simulation, and cost evaluation of two different cold storage systems for a single-family house in Italy, that differ from one another on the cold storage material. The two materials used to perform the numerical simulations of the cold storage systems are represented by cold water and a phase change material (PCM), and the numerical simulations have been realized by means of numerical codes written in Matlab environment. The main finding of the p...

  11. Combining Maize Base Germplasm for Cold Tolerance Breeding

    OpenAIRE

    Rodríguez Graña, Víctor Manuel; Butrón Gómez, Ana María; Sandoya Miranda, Germán; Ordás Pérez, Amando; Revilla Temiño, Pedro

    2007-01-01

    Early planting can contribute to increased grain yield of maize (Zea mays L.), but it requires cold tolerance. A limited number of cold-tolerant maize genotypes have been reported. The objectives of this study were to test a new strategy to improve cold tolerance in maize searching for broad x narrow genetic combinations that may be useful as base populations for breeding programs, to compare genotype performance under cold-controlled and field conditions, and to establish the major genetic e...

  12. 21 CFR 880.6085 - Hot/cold water bottle.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Hot/cold water bottle. 880.6085 Section 880.6085... Devices § 880.6085 Hot/cold water bottle. (a) Identification. A hot/cold water bottle is a device intended for medical purposes that is in the form of a container intended to be filled with hot or cold water...

  13. Features, Events, and Processes: Disruptive Events

    International Nuclear Information System (INIS)

    J. King

    2004-01-01

    The primary purpose of this analysis is to evaluate seismic- and igneous-related features, events, and processes (FEPs). These FEPs represent areas of natural system processes that have the potential to produce disruptive events (DE) that could impact repository performance and are related to the geologic processes of tectonism, structural deformation, seismicity, and igneous activity. Collectively, they are referred to as the DE FEPs. This evaluation determines which of the DE FEPs are excluded from modeling used to support the total system performance assessment for license application (TSPA-LA). The evaluation is based on the data and results presented in supporting analysis reports, model reports, technical information, or corroborative documents that are cited in the individual FEP discussions in Section 6.2 of this analysis report

  14. Features, Events, and Processes: Disruptive Events

    Energy Technology Data Exchange (ETDEWEB)

    J. King

    2004-03-31

    The primary purpose of this analysis is to evaluate seismic- and igneous-related features, events, and processes (FEPs). These FEPs represent areas of natural system processes that have the potential to produce disruptive events (DE) that could impact repository performance and are related to the geologic processes of tectonism, structural deformation, seismicity, and igneous activity. Collectively, they are referred to as the DE FEPs. This evaluation determines which of the DE FEPs are excluded from modeling used to support the total system performance assessment for license application (TSPA-LA). The evaluation is based on the data and results presented in supporting analysis reports, model reports, technical information, or corroborative documents that are cited in the individual FEP discussions in Section 6.2 of this analysis report.

  15. Cold chain management: Knowledge and practices in primary ...

    African Journals Online (AJOL)

    Administrator

    experience and their knowledge of cold chain was not as per required levels to support effective cold chain management. ... district directorates who then supply them to the various ..... Finn L, Crook S. A district survey of vaccine cold chain ...

  16. Cold stratification, but not stratification in salinity, enhances seedling ...

    African Journals Online (AJOL)

    Cold stratification, but not stratification in salinity, enhances seedling growth of wheat under salt treatment. L Wang, HL Wang, CH Yin, CY Tian. Abstract. Cold stratification was reported to release seed dormancy and enhance plant tolerance to salt stress. Experiments were conducted to test the hypothesis that cold ...

  17. 21 CFR 133.124 - Cold-pack cheese food.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Cold-pack cheese food. 133.124 Section 133.124 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD... Cheese and Related Products § 133.124 Cold-pack cheese food. (a)(1) Cold-pack cheese food is the food...

  18. Examples on cold forged aluminium components in automotive industry

    DEFF Research Database (Denmark)

    Bay, Niels; Kolsgaard, A.

    2000-01-01

    The present paper describes the possibilites of applying cold forging for manufacturing of light weight components in aluminium. A short description of the basic cold forming processes forms the basis for describing the great variety in design of cold forged components. Examples are mainly taken ...... from automotive industry but in a few cases also from other industrial sectors to show the possibilities....

  19. Safeguards summary event list (SSEL)

    International Nuclear Information System (INIS)

    Davidson, J.J.; MacMurdy, P.H.

    1980-12-01

    The List contains nine categories of events involving NRC licensed material or licensees. It is deliberately broad in scope for two main reasons. First, the list is designed to serve as a reference document. It is as complete and accurate as possible. Second, the list is intended to provide as broad a perspective of the nature of licensee-related events as possible. The nine categories of events are as follows: bomb-related events; intrusion events; missing and/or allegedly stolen events; transportation-related events; vandalism events; arson events; firearms-related events; sabotage events; and miscellaneous events

  20. Features, Events, and Processes: Disruptive Events

    Energy Technology Data Exchange (ETDEWEB)

    P. Sanchez

    2004-11-08

    The purpose of this analysis report is to evaluate and document the inclusion or exclusion of the disruptive events features, events, and processes (FEPs) with respect to modeling used to support the total system performance assessment for license application (TSPA-LA). A screening decision, either ''Included'' or ''Excluded,'' is given for each FEP, along with the technical basis for screening decisions. This information is required by the U.S. Nuclear Regulatory Commission (NRC) at 10 CFR 63.114 (d), (e), and (f) [DIRS 156605]. The FEPs addressed in this report deal with both seismic and igneous disruptive events, such as fault displacements through the repository and an igneous intrusion into the repository. For included FEPs, this analysis summarizes the implementation of the FEP in TSPA-LA (i.e., how the FEP is included). For excluded FEPs, this analysis provides the technical basis for exclusion from TSPA-LA (i.e., why the FEP is excluded). Previous versions of this report were developed to support the total system performance assessments (TSPA) for various prior repository designs. This revision addresses the repository design for the license application (LA).

  1. Features, Events, and Processes: Disruptive Events

    International Nuclear Information System (INIS)

    P. Sanchez

    2004-01-01

    The purpose of this analysis report is to evaluate and document the inclusion or exclusion of the disruptive events features, events, and processes (FEPs) with respect to modeling used to support the total system performance assessment for license application (TSPA-LA). A screening decision, either ''Included'' or ''Excluded,'' is given for each FEP, along with the technical basis for screening decisions. This information is required by the U.S. Nuclear Regulatory Commission (NRC) at 10 CFR 63.114 (d), (e), and (f) [DIRS 156605]. The FEPs addressed in this report deal with both seismic and igneous disruptive events, such as fault displacements through the repository and an igneous intrusion into the repository. For included FEPs, this analysis summarizes the implementation of the FEP in TSPA-LA (i.e., how the FEP is included). For excluded FEPs, this analysis provides the technical basis for exclusion from TSPA-LA (i.e., why the FEP is excluded). Previous versions of this report were developed to support the total system performance assessments (TSPA) for various prior repository designs. This revision addresses the repository design for the license application (LA)

  2. Exhaust Emission Characteristics of Heavy Duty Diesel Engine During Cold and Warm Start

    Directory of Open Access Journals (Sweden)

    YANG Rong

    2014-07-01

    Full Text Available Through experiment conducted on a six cylinder direct injection diesel engine with SCR catalyst, effects of coolant temperature on rail pressure, injection quantity, excess air coefficient and emissions characteristics during cold and warm start were investigated. The results showed that, the maximum injection quantity during a starting event was several times higher than idling operation mode, so was the maximal opacity in the cold and warm starting process. When coolant temperature rose up to above 20℃, NOX emissions in the starting process exhibited peculiar rise which was times higher than idling mode. Compared with engine warm start, rail pressure, cycle fuel quantity, opacity, CO and HC emissions during engine cold start were higher in the course from their transient maximal values towards stabilized idling status. NOX in the same transient course, however, were lower in cold start. As coolant temperature rose, the maximal and the idling value of rail pressure and cycle fuel injection quantity during diesel engine starting process decreased gradually, the excess air coefficient increased to a certain degree, and the maximal and idling values of NOX increased gradually.

  3. Human Performance Event Database

    International Nuclear Information System (INIS)

    Trager, E. A.

    1998-01-01

    The purpose of this paper is to describe several aspects of a Human Performance Event Database (HPED) that is being developed by the Nuclear Regulatory Commission. These include the background, the database structure and basis for the structure, the process for coding and entering event records, the results of preliminary analyses of information in the database, and plans for the future. In 1992, the Office for Analysis and Evaluation of Operational Data (AEOD) within the NRC decided to develop a database for information on human performance during operating events. The database was needed to help classify and categorize the information to help feedback operating experience information to licensees and others. An NRC interoffice working group prepared a list of human performance information that should be reported for events and the list was based on the Human Performance Investigation Process (HPIP) that had been developed by the NRC as an aid in investigating events. The structure of the HPED was based on that list. The HPED currently includes data on events described in augmented inspection team (AIT) and incident investigation team (IIT) reports from 1990 through 1996, AEOD human performance studies from 1990 through 1993, recent NRR special team inspections, and licensee event reports (LERs) that were prepared for the events. (author)

  4. The Agency of Event

    DEFF Research Database (Denmark)

    Nicholas, Paul; Tamke, Martin; Riiber, Jacob

    2014-01-01

    This paper explores the notion of agency within event-based models. We present an event-based modeling approach that links interdependent generative, analytic and decision making sub-models within a system of exchange. Two case study projects demonstrate the underlying modeling concepts and metho...

  5. Intermediate mass dimuon events

    International Nuclear Information System (INIS)

    Moser, H.-G.

    1985-01-01

    We report the observation of 67 dimuon events at the CERN p anti p collider with the UA1 detector. The events will be interpreted in terms of the Drell-Yan mechanism, J/PSI and UPSILON decays and heavy flavour production. (author)

  6. The Blayais event

    International Nuclear Information System (INIS)

    2000-01-01

    This document provides the main events occurred to the Blayais installation during the year 2000. For each events, the detailed chronology, the situation analysis, the crisis management and the public information are provided. Some recommendations are also provided by the nuclear safety authorities. (A.L.B.)

  7. Use of cough and cold preparations during breastfeeding.

    Science.gov (United States)

    Mitchell, J L

    1999-12-01

    Adverse reactions in infants from maternal drug ingestion depend largely on the amount of milk consumed by the infant, timing of breastfeeding in relation to dosing, dose of the medication, dosing interval, and duration of therapy. When taking medications, breastfeeding mothers should be instructed to take their medication after breastfeeding, at the lowest effective dose and for the shortest duration. Overall, there are few data from human studies on the use of antihistamines, decongestants, and cough products during breastfeeding. Studies of pseudoephedrine, triprolidine, and loratadine in humans conclude that low levels of each drug would reach a breastfed infant. Since triprolidine and pseudoephedrine are also considered compatible with breastfeeding by the AAP, these 2 drugs should be the first-line choices. Codeine is considered compatible with breastfeeding by the AAP, and would be an acceptable choice for short-term use as a cough suppressant. It is important to note that many of the liquid cough and cold products contain alcohol. In addition, many of the combination products are a mixture of an antihistamine and a decongestant and may also contain aspirin, acetaminophen, ibuprofen, or caffeine. It is preferable for nursing mothers to only take medications that are necessary and to avoid such combination products. The AAP considers alcohol, acetaminophen, ibuprofen, and caffeine compatible with breastfeeding. Aspirin has been associated with significant negative effects on some nursing infants, and the AAP recommends giving aspirin to nursing mothers with caution. Mothers taking cough and cold products should watch for adverse events in their breastfed infants. Infants may experience paradoxical central nervous stimulation from antihistamines and irritability and insomnia from decongestants.

  8. Interaction of Shallow Cold Surges with Topography on Scales of 100-1000 Kilometers.

    Science.gov (United States)

    Toth, James John

    1987-09-01

    A shallow cold air mass is defined as one not extending to the top of the mountain ridge with which it interacts. The structure of such an airmass is examined using both observational data and a hydrostatic version of the Colorado State University Regional Atmospheric Modeling System. The prime constraint on a shallow cold surge is that the flow must ultimately be parallel to the mountain ridge. It is found that the effects of this constraint are altered significantly by surface sensible heat flux. Cold surges are slowed during the daylight hours, a result consistent with previous observational studies in Colorado east of the Continental Divide. Two case studies are described in detail, and several other events are cited. Since observations alone do not provide a complete description of diversion of the cold air by the mountain range, numerical model simulations provide additional insight into important mechanisms. A case study on 14 June 1985 is described using observational and model data. The model development of a deep boundary layer within the frontal baroclinic zone is consistent with the observations for this and other cases. This development is due to strong surface heating. Turning off the model shortwave radiation is seen to produce a rapid southward acceleration of the surface front, with very shallow cold air behind the front. Model simulations with specified surface temperature differences confirm the importance of upward heat flux from the surface in slowing the southward movement of the cold surge. It is concluded that the slowing is not due simply to the thermal wind developing in response to the heating of higher terrain to the west. Since surface heating is distributed over a deeper layer on the warm side of the temperature discontinuity, there is frontolysis at the surface. But this modification would develop even over flat terrain. Sloping terrain introduces additional effects. Heating at the western, upslope side of the cold surge inhibits the

  9. Cold-Season Tornadoes: Climatological, Meteorological, and Social Perspectives

    Science.gov (United States)

    Childs, Samuel J.

    the variance in counts. A second perspective focuses on meteorological environments that characterize NDJF tornadoes through use of the NCEP/NCAR Reanalysis. Upon comparing the most tornadic and least tornadic cold seasons, it is found that active seasons are characterized by a large trough in the western U.S.; warm and moist conditions across the Southeast, likely due to an enhanced low-level jet transport from the western Gulf of Mexico; and enhanced 1000-500-hPa wind speed shear. The third perspective addressed in this thesis is that of social science. A case study of four tornado events from November 2016-February 2017, in which a post-event survey is disseminated to NWS meteorologists, broadcast meteorologists, and emergency managers, is carried out to assess strategies and barriers professionals face when communicating cold-season tornado risk and warnings to their respective communities. The survey also aims to shed light on the perceived levels of human preparedness, vulnerability, and resiliency from the professional's point of view. In addition to unique, case-specific challenges, the professionals expressed major barriers to communication due to inconsistency of messages and graphics, and an inability to give the public information on fine enough temporal and spatial scales. Each decision-making sector noted a high local vulnerability to tornadoes in general, mostly brought on by lack of education and/or resources. However, most professionals perceive their communities to be aware of cold-season tornado risk and thus adequately prepared and resilient when they occur. The survey results also confirm the desire and need for better collaboration among professionals, and with social scientists, in order to adequately educate and warn all sectors of society from tornado risk, especially those during times of year they are not typically expected. Harnessing all three perspectives presented in this study provides a much deeper understanding of NDJF tornadoes and

  10. Finishing of the cold mass assembly

    CERN Multimedia

    Maximilien Brice

    2001-01-01

    Photo 1 Zoom of the lyre-side end of the active part assembly. The extremity of the shrinking cylinder has been bevelled in view of welding the end cover. Photo 2 General view of the finishing station showing the special supporting structures (blue and yellow structures) needed for the geometric measurements and for the alignment operations. Photo 3 Zoom of the lyre-side end of the active part assembly. One can also see the auxiliary bus bars needed to power the corrector magnets that are installed in the dipole cold mass assembly. Photo 4 Technicians are putting in order the instrumentation wires. The prototype magnets were equipped with numerous sensors to monitor key parameters during the performance tests at cold conditions.

  11. Indian foreign policy during the cold war

    International Nuclear Information System (INIS)

    Ross, Cesar

    2010-01-01

    This article examines India's foreign policy priorities during the years of the Cold War with a focus on international relations. As in the rest of the world, the India's foreign policy was marked by the dynamics of continuity and change in world policy, associated with the historical period of the Cold War (1947-90) and its impact on the neighbouring and regional context of India. As its hypothesis this article argues that this period was characterized by the challenges of consolidating the autonomy of independence, which means: achieving development; solving disputes arising from conflicts with neighbours; and, presenting India as a country committed to peace, which explains not only its position against war and the use of nuclear weapons, but also, with respect to one of the most original aspects of Indian foreign policy, its status as a non-aligned country

  12. Electrical model of cold atmospheric plasma gun

    Science.gov (United States)

    Slutsker, Ya. Z.; Semenov, V. E.; Krasik, Ya. E.; Ryzhkov, M. A.; Felsteiner, J.; Binenbaum, Y.; Gil, Z.; Shtrichman, R.; Cohen, J. T.

    2017-10-01

    We present an analytical model of cold atmospheric plasma formed by a dielectric barrier discharge (DBD), which is based on the lumped and distributed elements of an equivalent electric circuit of this plasma. This model is applicable for a wide range of frequencies and amplitudes of the applied voltage pulses, no matter whether or not the generated plasma plume interacts with a target. The model allows quantitative estimation of the plasma plume length and the energy delivered to the plasma. Also, the results of this model can be used for the design of DBD guns which efficiently generate cold atmospheric plasma. A comparison of the results of the model with those obtained in experiments shows a fairly good agreement.

  13. COLD-SAT feasibility study safety analysis

    Science.gov (United States)

    Mchenry, Steven T.; Yost, James M.

    1991-01-01

    The Cryogenic On-orbit Liquid Depot-Storage, Acquisition, and Transfer (COLD-SAT) satellite presents some unique safety issues. The feasibility study conducted at NASA-Lewis desired a systems safety program that would be involved from the initial design in order to eliminate and/or control the inherent hazards. Because of this, a hazards analysis method was needed that: (1) identified issues that needed to be addressed for a feasibility assessment; and (2) identified all potential hazards that would need to be controlled and/or eliminated during the detailed design phases. The developed analysis method is presented as well as the results generated for the COLD-SAT system.

  14. Cold fusion catalyzed by muons and electrons

    International Nuclear Information System (INIS)

    Kulsrud, R.M.

    1990-10-01

    Two alternative methods have been suggested to produce fusion power at low temperature. The first, muon catalyzed fusion or MCF, uses muons to spontaneously catalyze fusion through the muon mesomolecule formation. Unfortunately, this method fails to generate enough fusion energy to supply the muons, by a factor of about ten. The physics of MCF is discussed, and a possible approach to increasing the number of MCF fusions generated by each muon is mentioned. The second method, which has become known as ''Cold Fusion,'' involves catalysis by electrons in electrolytic cells. The physics of this process, if it exists, is more mysterious than MCF. However, it now appears to be an artifact, the claims for its reality resting largely on experimental errors occurring in rather delicate experiments. However, a very low level of such fusion claimed by Jones may be real. Experiments in cold fusion will also be discussed

  15. Fusion - still out in the cold

    International Nuclear Information System (INIS)

    Townsley, Mike.

    1989-01-01

    Scepticism over the claims made by Professors Martin Fleischman and Stanley Pons about cold fusion is expressed. The background to their experiment and announcement of their results is given. Other research teams have failed to repeat the experiment which claims that deuterium nuclei fused in a special electrochemical cell. If tritium is also produced, as is claimed, this would have important military implications as tritium is used in hydrogen bombs. Failing cold fusion, there is always the JET project but after 10 years and an expenditure of Pound 600 million that has failed to produce a net energy gain it would be better to spend the money developing renewable energy sources. (U.K.)

  16. Axion cold dark matter in nonstandard cosmologies

    International Nuclear Information System (INIS)

    Visinelli, Luca; Gondolo, Paolo

    2010-01-01

    We study the parameter space of cold dark matter axions in two cosmological scenarios with nonstandard thermal histories before big bang nucleosynthesis: the low-temperature reheating (LTR) cosmology and the kination cosmology. If the Peccei-Quinn symmetry breaks during inflation, we find more allowed parameter space in the LTR cosmology than in the standard cosmology and less in the kination cosmology. On the contrary, if the Peccei-Quinn symmetry breaks after inflation, the Peccei-Quinn scale is orders of magnitude higher than standard in the LTR cosmology and lower in the kination cosmology. We show that the axion velocity dispersion may be used to distinguish some of these nonstandard cosmologies. Thus, axion cold dark matter may be a good probe of the history of the Universe before big bang nucleosynthesis.

  17. Screening Prosopis (mesquite) for cold tolerance

    Energy Technology Data Exchange (ETDEWEB)

    Felker, P. (Texas AandI Univ., Kingsville); Clark, P.R.; Nash, P.; Osborn, J.F.; Cannell, G.H.

    1982-09-01

    Cold tolerance and biomass estimation of Prosopis species were examined under field conditions. Prosopis africana and P. pallida tolerated several minus 1.5/sup 0/C freezes but none survived a minus 5/sup 0/C freeze. P. alba, P. articulata, P. chilensis, P. nigra, and P. tamarugo tolerated several minus 5/sup 0/C freezes but not a 12-hour below 0/sup 0/C freeze. Most North American native species P. glandulosa var. glandulosa, P. glandulosa var. torreyana, and P. velutina tolerated the 12 hour freeze with only moderate damage. In general trees with greater productivity belonged to the most cold sensitive accessions but sufficient variability exists to substantially improve Prosopis biomass production on the coldest areas where it now naturally occurs.

  18. Cryogenic target formation using cold gas jets

    International Nuclear Information System (INIS)

    Hendricks, C.D.

    1980-01-01

    A method and apparatus using cold gas jets for producing a substantially uniform layer of cryogenic materials on the inner surface of hollow spherical members having one or more layers, such as inertially imploded targets, are described. By vaporizing and quickly refreezing cryogenic materials contained within a hollow spherical member, a uniform layer of the materials is formed on an inner surface of the spherical member. Basically the method involves directing cold gas jets onto a spherical member having one or more layers or shells and containing the cryogenic material, such as a deuterium-tritium (DT) mixture, to freeze the contained material, momentarily heating the spherical member so as to vaporize the contained material, and quickly refreezing the thus vaporized material forming a uniform layer of cryogenic material on an inner surface of the spherical member

  19. Outer crust of nonaccreting cold neutron stars

    International Nuclear Information System (INIS)

    Ruester, Stefan B.; Hempel, Matthias; Schaffner-Bielich, Juergen

    2006-01-01

    The properties of the outer crust of nonaccreting cold neutron stars are studied by using modern nuclear data and theoretical mass tables, updating in particular the classic work of Baym, Pethick, and Sutherland. Experimental data from the atomic mass table from Audi, Wapstra, and Thibault of 2003 are used and a thorough comparison of many modern theoretical nuclear models, both relativistic and nonrelativistic, is performed for the first time. In addition, the influences of pairing and deformation are investigated. State-of-the-art theoretical nuclear mass tables are compared to check their differences concerning the neutron drip line, magic neutron numbers, the equation of state, and the sequence of neutron-rich nuclei up to the drip line in the outer crust of nonaccreting cold neutron stars

  20. Rapid cold hardening: a gut feeling.

    Science.gov (United States)

    Worland, M R; Convey, P; Luke ov , A

    2000-01-01

    This study examined the rate of cold hardening of a field population of Antarctic springtails and the effect of eating food with particular levels of ice nucleating activity on the animal's whole body freezing point. The SCPs of samples of c. 20, freshly collected, Cryptopygus antarcticus were measured hourly over a 32 hour collection period using differential scanning calorimetry and related to habitat temperature. The mean SCP of the springtails increased from -24 to -10 degree C during which time the habitat temperature warmed slowly from -2.5 to +2.5 degree C. In laboratory experiments, previously starved, cold tolerant springtails were fed on selected species of algae with measured SCP's but there was no clear correlation between the SCP of food and that of the animals after feeding. Microscopic examination of faecal pellets and guts from springtails showed that algal cells were completely destroyed during digestion.

  1. Cold Leak Tests of LHC Beam Screens

    CERN Document Server

    Collomb-Patton, C; Jenninger, B; Kos, N

    2009-01-01

    In order to guide the high energy proton beams inside its two 27 km long vacuum rings, the Large Hadron Collider (LHC) at CERN, Geneva, makes use of superconducting technology to create the required magnetic fields. More than 4000 beam screens, cooled at 7 20 K, are inserted inside the 1.9 K beam vacuum tubes to intercept beam induced heat loads and to provide dynamic vacuum stability. As extremely high helium leak tightness is required, all beam screens have been leak tested under cold conditions in a dedicated test stand prior to their installation. After describing the beam screen design and its functions, this report focuses on the cold leak test sequence and discusses the results.

  2. Extreme hydrometeorological events in the Peruvian Central Andes during austral summer and their relationship with the large-scale circulation

    Science.gov (United States)

    Sulca, Juan C.

    In this Master's dissertation, atmospheric circulation patterns associated with extreme hydrometeorological events in the Mantaro Basin, Peruvian Central Andes, and their teleconnections during the austral summer (December-January-February-March) are addressed. Extreme rainfall events in the Mantaro basin are related to variations of the large-scale circulation as indicated by the changing strength of the Bolivian High-Nordeste Low (BH-NL) system. Dry (wet) spells are associated with a weakening (strengthening) of the BH-NL system and reduced (enhanced) influx of moist air from the lowlands to the east due to strengthened westerly (easterly) wind anomalies at mid- and upper-tropospheric levels. At the same time extreme rainfall events of the opposite sign occur over northeastern Brazil (NEB) due to enhanced (inhibited) convective activity in conjunction with a strengthened (weakened) Nordeste Low. Cold episodes in the Mantaro Basin are grouped in three types: weak, strong and extraordinary cold episodes. Weak and strong cold episodes in the MB are mainly associated with a weakening of the BH-NL system due to tropical-extratropical interactions. Both types of cold episodes are associated with westerly wind anomalies at mid- and upper-tropospheric levels aloft the Peruvian Central Andes, which inhibit the influx of humid air masses from the lowlands to the east and hence limit the potential for development of convective cloud cover. The resulting clear sky conditions cause nighttime temperatures to drop, leading to cold extremes below the 10-percentile. Extraordinary cold episodes in the MB are associated with cold and dry polar air advection at all tropospheric levels toward the central Peruvian Andes. Therefore, weak and strong cold episodes in the MB appear to be caused by radiative cooling associated with reduced cloudiness, rather than cold air advection, while the latter plays an important role for extraordinary cold episodes only.

  3. Universal subhalo accretion in cold and warm dark matter cosmologies

    Science.gov (United States)

    Kubik, Bogna; Libeskind, Noam I.; Knebe, Alexander; Courtois, Hélène; Yepes, Gustavo; Gottlöber, Stefan; Hoffman, Yehuda

    2017-12-01

    The influence of the large-scale structure on host haloes may be studied by examining the angular infall pattern of subhaloes. In particular, since warm dark matter (WDM) and cold dark matter (CDM) cosmologies predict different abundances and internal properties for haloes at the low-mass end of the mass function, it is interesting to examine if there are differences in how these low-mass haloes are accreted. The accretion events are defined as the moment a halo becomes a substructure, namely when it crosses its host's virial radius. We quantify the cosmic web at each point by the shear tensor and examine where, with respect to its eigenvectors, such accretion events occur in ΛCDM and ΛWDM (1 keV sterile neutrino) cosmological models. We find that the CDM and WDM subhaloes are preferentially accreted along the principal axis of the shear tensor corresponding to the direction of weakest collapse. The beaming strength is modulated by the host and subhalo masses and by the redshift at which the accretion event occurs. Although strongest for the most massive hosts and subhaloes at high redshift, the preferential infall is found to be always aligned with the axis of weakest collapse, thus we say that it has universal nature. We compare the strength of beaming in the ΛWDM cosmology with the one found in the ΛCDM scenario. While the main findings remain the same, the accretion in the ΛWDM model for the most massive host haloes appears more beamed than in ΛCDM cosmology across all the redshifts.

  4. How cold is it? TRPM8 and TRPA1 in the molecular logic of cold sensation

    Directory of Open Access Journals (Sweden)

    McKemy David D

    2005-04-01

    Full Text Available Abstract Recognition of temperature is a critical element of sensory perception and allows us to evaluate both our external and internal environments. In vertebrates, the somatosensory system can discriminate discrete changes in ambient temperature, which activate nerve endings of primary afferent fibers. These thermosensitive nerves can be further segregated into those that detect either innocuous or noxious (painful temperatures; the latter neurons being nociceptors. We now know that thermosensitive afferents express ion channels of the transient receptor potential (TRP family that respond at distinct temperature thresholds, thus establishing the molecular basis for thermosensation. Much is known of those channels mediating the perception of noxious heat; however, those proposed to be involved in cool to noxious cold sensation, TRPM8 and TRPA1, have only recently been described. The former channel is a receptor for menthol, and links the sensations provided by this and other cooling compounds to temperature perception. While TRPM8 almost certainly performs a critical role in cold signaling, its part in nociception is still at issue. The latter channel, TRPA1, is activated by the pungent ingredients in mustard and cinnamon, but has also been postulated to mediate our perception of noxious cold temperatures. However, a number of conflicting reports have suggested that the role of this channel in cold sensation needs to be confirmed. Thus, the molecular logic for the perception of cold-evoked pain remains enigmatic. This review is intended to summarize our current understanding of these cold thermoreceptors, as well as address the current controversy regarding TRPA1 and cold signaling.

  5. Observation of tritium in cold fusion experiments

    International Nuclear Information System (INIS)

    Krishnan, M.S.; Malhotra, S.K.; Gaonkar, D.G.; Sadhukhan, H.K.

    1990-01-01

    This paper describes the results of tritium measurements carried out during the electrolysis of heavy water in different electrolysers employing palladium and titanium as cathodes. The tritium level of electrolytes have been found to be many orders of magnitudes higher than what can be explained on the basis of isotope enrichment and evaporation during electrolysis. The neutron measurement results have also been included and these observations have been attributed to the phenomenon of cold fusion. (author). 6 refs., 1 tab

  6. Astrochemical Properties of Planck Cold Clumps

    Energy Technology Data Exchange (ETDEWEB)

    Tatematsu, Ken’ichi; Sanhueza, Patricio; Nguyễn Lu’o’ng, Quang; Hirota, Tomoya [National Astronomical Observatory of Japan, National Institutes of Natural Sciences, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Liu, Tie; Choi, Minho; Kang, Miju; Kim, Kee-Tae [Korea Astronomy and Space Science Institute, Daedeokdaero 776, Yuseong, Daejeon 305-348 (Korea, Republic of); Ohashi, Satoshi [Department of Astronomy, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033 (Japan); Liu, Sheng-Yuan; Hirano, Naomi [Academia Sinica Institute of Astronomy and Astrophysics, 11F of Astronomy-Mathematics Building, AS/NTU. No.1, Section 4, Roosevelt Rd, Taipei 10617, Taiwan (China); Thompson, Mark A. [Centre for Astrophysics Research, Science and Technology Research Institute, University of Hertfordshire, Hatfield, AL10 9AB (United Kingdom); Fuller, Gary [Jodrell Bank Centre for Astrophysics, School of Physics and Astronomy, University of Manchester, Oxford Road, Manchester, M13 9PL (United Kingdom); Wu, Yuefang [Department of Astronomy, Peking University, 100871, Beijing (China); Li, Di [National Astronomical Observatories, Chinese Academy of Sciences, Beijing, 100012 (China); Francesco, James Di [NRC Herzberg Astronomy and Astrophysics, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada); Wang, Ke [European Southern Observatory (Germany); Ristorcelli, Isabelle [IRAP, CNRS (UMR5277), Universite Paul Sabatier, 9 avenue du Colonel Roche, BP 44346, F-31028, Toulouse Cedex 4 (France); Juvela, Mika [Department of physics, University of Helsinki, FI-00014, Helsinki (Finland); Shinnaga, Hiroko, E-mail: k.tatematsu@nao.ac.jp [Department of Physics, Kagoshima University, 1-21-35, Korimoto, Kagoshima, 890-0065 (Japan); Collaboration: JCMT Large Program “SCOPE” collaboration; TRAO Key Science Program “TOP” collaboration; and others

    2017-02-01

    We observed 13 Planck cold clumps with the James Clerk Maxwell Telescope/SCUBA-2 and with the Nobeyama 45 m radio telescope. The N{sub 2}H{sup +} distribution obtained with the Nobeyama telescope is quite similar to SCUBA-2 dust distribution. The 82 GHz HC{sub 3}N, 82 GHz CCS, and 94 GHz CCS emission are often distributed differently with respect to the N{sub 2}H{sup +} emission. The CCS emission, which is known to be abundant in starless molecular cloud cores, is often very clumpy in the observed targets. We made deep single-pointing observations in DNC, HN{sup 13}C, N{sub 2}D{sup +}, and cyclic-C{sub 3}H{sub 2} toward nine clumps. The detection rate of N{sub 2}D{sup +} is 50%. Furthermore, we observed the NH{sub 3} emission toward 15 Planck cold clumps to estimate the kinetic temperature, and confirmed that most targets are cold (≲20 K). In two of the starless clumps we observed, the CCS emission is distributed as it surrounds the N{sub 2}H{sup +} core (chemically evolved gas), which resembles the case of L1544, a prestellar core showing collapse. In addition, we detected both DNC and N{sub 2}D{sup +}. These two clumps are most likely on the verge of star formation. We introduce the chemical evolution factor (CEF) for starless cores to describe the chemical evolutionary stage, and analyze the observed Planck cold clumps.

  7. Cold fusion - no end of discussion

    International Nuclear Information System (INIS)

    Seifritz, W.

    1991-01-01

    In March 1989, Stanley Pons and Martin Fleischmann from the University of Utah/USA reported that they had discovered sporadic heat releases of non-chemical character in electro-chemical cells using palladium electrodes and heavy water. In the meantime, a series of new papers have been published in which similar effects and various explanations were described, although a number of qualified international research instituts could not confirm these findings. The subject matter 'cold fusion' is analysed critically. (orig.) [de

  8. Cold Vacuum Drying Facility hazard analysis report

    Energy Technology Data Exchange (ETDEWEB)

    Krahn, D.E.

    1998-02-23

    This report describes the methodology used in conducting the Cold Vacuum Drying Facility (CVDF) hazard analysis to support the CVDF phase 2 safety analysis report (SAR), and documents the results. The hazard analysis was performed in accordance with DOE-STD-3009-94, Preparation Guide for US Department of Energy Nonreactor Nuclear Facility Safety Analysis Reports, and implements the requirements of US Department of Energy (DOE) Order 5480.23, Nuclear Safety Analysis Reports.

  9. Cold Vacuum Drying Facility hazard analysis report

    International Nuclear Information System (INIS)

    Krahn, D.E.

    1998-01-01

    This report describes the methodology used in conducting the Cold Vacuum Drying Facility (CVDF) hazard analysis to support the CVDF phase 2 safety analysis report (SAR), and documents the results. The hazard analysis was performed in accordance with DOE-STD-3009-94, Preparation Guide for US Department of Energy Nonreactor Nuclear Facility Safety Analysis Reports, and implements the requirements of US Department of Energy (DOE) Order 5480.23, Nuclear Safety Analysis Reports

  10. Sustainable Algae Biodiesel Production in Cold Climates

    OpenAIRE

    Baliga, Rudras; Powers, Susan E.

    2010-01-01

    This life cycle assessment aims to determine the most suitable operating conditions for algae biodiesel production in cold climates to minimize energy consumption and environmental impacts. Two hypothetical photobioreactor algae production and biodiesel plants located in Upstate New York (USA) are modeled. The photobioreactor is assumed to be housed within a greenhouse that is located adjacent to a fossil fuel or biomass power plant that can supply waste heat and flue gas containing CO2 as a ...

  11. Spatial distribution of cold antihydrogen formation

    International Nuclear Information System (INIS)

    Madsen, N.; Hangst, J.S.; Amoretti, M.; Carraro, C.; Macri, M.; Testera, G.; Variola, A.; Amsler, C.; Pruys, H.; Regenfus, C.; Bonomi, G.; Doser, M.; Kellerbauer, A.; Landua, R.; Bowe, P.D.; Charlton, M.; Joergensen, L.V.; Mitchard, D.; Werf, D.P. van der; Cesar, C.L.

    2005-01-01

    Antihydrogen is formed when antiprotons are mixed with cold positrons in a nested Penning trap. We present experimental evidence, obtained using our antihydrogen annihilation detector, that the spatial distribution of the emerging antihydrogen atoms is independent of the positron temperature and axially enhanced. This indicates that antihydrogen is formed before the antiprotons are in thermal equilibrium with the positron plasma. This result has important implications for the trapping and spectroscopy of antihydrogen

  12. Temporal characteristics of cold pain perception.

    Science.gov (United States)

    Frölich, Michael A; Bolding, Mark S; Cutter, Gary R; Ness, Timothy J; Zhang, Kui

    2010-08-09

    Adaptation to a sustained stimulus is an important phenomenon in psychophysical experiments. When studying the response to an experimental task, the investigator has to account for the change in perceived stimulus intensity with repeated stimulus application and, if the stimulus is sustained, for the change in intensity during the presentation. An example of a sustained stimulus is the cold pressor task (CPT). The task has been used both as an experimental pain task and to study cardiovascular physiology. In functional imaging research, the CPT has been used to evaluate cognitive processing of a noxious stimulus. Investigators typically model the stimulus in a block design as a categorical (on-off) stimulus and do not account for a temporal change in stimulus perception. If the perceived stimulus changes over time, the results may be misleading. Therefore, we characterized the time course of cold pain in human volunteers and developed a model of the temporal characteristics of perceived cold pain. Fifteen healthy participants underwent cold pain testing by immersing their right foot into a container filled with ice water (2 degrees C) for 30s alternating with a 30s immersion into a container filled with tepid water 32 degrees C (control). Participants rated the pain intensity using an electronic slide algometer. Using a mixed general linear model (effectively a polynomial regression model), we determined that pain ratings follow a crescendo-decrescendo pattern that can be described well using a quadratic model. We conclude that the time course of quantitative perception differs fundamentally from the time course of stimulus presentation. This may be important when looking for the physiological correlates of perception as opposed to the presence of a stimulus per se. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

  13. Mountain Warfare and Cold Weather Operations

    Science.gov (United States)

    2016-04-29

    is important to determine whether the bottom is composed of sand, gravel, silt, clay , or rock and in what proportions. For more information see ATP...these planning factors by about two quarts per individual. 6-22. Water increases in viscosity in extreme cold weather, and therefore moves slower...In arctic conditions, fuel spilled on flesh can cause instant frostbite if the proper gloves are not worn. 6-32. Multi- viscosity oil (15W-40) is

  14. Manipulating cold atoms for quantum information processing

    International Nuclear Information System (INIS)

    Knight, P.

    2005-01-01

    Full text: I will describe how cold atoms can be manipulated to realize arrays of addressable qbits as prototype quantum registers, focussing on how atom chips can be used in combination with cavity qed techniques to form such an array. I will discuss how the array can be generated and steered using optical lattices and the Mott transition, and describe the sources of noise and how these place limits on the use of such chips in quantum information processing. (author)

  15. Frequent extreme cold exposure and brown fat and cold-induced thermogenesis: A study in a monozygotic twin

    NARCIS (Netherlands)

    M.J. Vosselman (Maarten J.); G.H.E.J. Vijgen (Guy H. E. J.); B.R.M. Kingma (Boris R. M.); B. Brans (Boudewijn); W.D. Van Marken Lichtenbelt (Wouter D.)

    2014-01-01

    textabstractIntroduction: Mild cold acclimation is known to increase brown adipose tissue (BAT) activity and cold-induced thermogenesis (CIT) in humans. We here tested the effect of a lifestyle with frequent exposure to extreme cold on BAT and CIT in a Dutch man known as 'the Iceman', who has

  16. Cold cathode arc model in mercury discharges

    International Nuclear Information System (INIS)

    Li, Y.M.; Byszewski, W.W.; Budinger, A.B.

    1990-01-01

    Voltage/current characteristics measured during the starting of metal halide lamps indicate a low voltage discharge when condensates (mainly mercury) are localized on the electrodes. In this case, even with a cold cathode which does not emit electrons, the current is very high and voltage across the lamp drops to about 15 to 20 V. This type of discharge is similar to the cold cathode mercury vapor arc found in mercury pool rectifiers. The cathode sheath in the mercury vapor arc is characterized by very small cathode spot size, on the order of 10 -c cm 2 , very high current density of about 10 6 A/cm 2 and very low cathode fall of approximately 10 volts. The discharge is modified and generalized to describe the cathode phenomena in the cold cathode mercury vapor arc. The sensitivity of calculated discharge parameters with respect to such modifications were examined. Results show that the cathode fall voltage remains fairly constant (7-8 volts) with large fractional variations of metastable mercury atoms bombarding the cathode. This result compares very well with experimental waveforms when anode fall and plasma voltage approximations are incorporated

  17. Anomalous cold in the Pangaean tropics

    Science.gov (United States)

    Soreghan, G.S.; Soreghan, M.J.; Poulsen, C.J.; Young, R.A.; Eble, C.F.; Sweet, D.E.; Davogustto, O.C.

    2008-01-01

    The late Paleozoic archives the greatest glaciation of the Phanerozoic. Whereas high-latitude Gondwanan strata preserve widespread evidence for continental ice, the Permo-Carboniferous tropics have long been considered analogous to today's: warm and shielded from the highlatitude cold. Here, we report on glacial and periglacial indicators that record episodes of freezing continental temperatures in western equatorial Pangaea. An exhumed glacial valley and associated deposits record direct evidence for glaciation that extended to low paleoelevations in the ancestral Rocky Mountains. Furthermore, the Permo-Carboniferous archives the only known occurrence of widespread tropical loess in Earth's history; the volume, chemistry, and provenance of this loess(ite) is most consistent with glacial derivation. Together with emerging indicators for cold elsewhere in low-latitude Pangaea, these results suggest that tropical climate was not buffered from the high latitudes and may record glacial-interglacial climate shifts of very large magnitude. Coupled climate-ice sheet model simulations demonstrate that low atmospheric CO2 and solar luminosity alone cannot account for such cold, and that other factors must be considered in attempting to explain this 'best-known' analogue to our present Earth. ?? 2008 The Geological Society of America.

  18. The University of Texas Cold Neutron Source

    International Nuclear Information System (INIS)

    Uenlue, Kenan; Rios-Martinez, Carlos; Wehring, B.W.

    1994-01-01

    A cold neutron source has been designed, constructed, and tested by the Nuclear Engineering Teaching Laboratory (NETL) at The University of Texas at Austin. The Texas Cold Neutron Source (TCNS) is located in one of the beam ports of the NETL 1-MW TRIGA Mark II research reactor. The main components of the TCNS are a cooled moderator, a heat pipe, a cryogenic refrigerator, and a neutron guide. 80 ml of mesitylene moderator are maintained at about 30 K in a chamber within the reactor graphite reflector by the heat pipe and cryogenic refrigerator. The heat pipe is a 3-m long aluminum tube that contains neon as the working fluid. The cold neutrons obtained from the moderator are transported by a curved 6-m long neutron guide. This neutron guide has a radius of curvature of 300 m, a 50x15 mm cross-section, 58 Ni coating, and is separated into three channels. The TCNS will provide a low-background subthermal neutron beam for neutron capture and scattering research. After the installation of the external portion of the neutron guide, a neutron focusing system and a Prompt Gamma Activation Analysis facility will be set up at the TCNS. ((orig.))

  19. Cold moderator test facilities working group

    International Nuclear Information System (INIS)

    Bauer, Guenter S.; Lucas, A. T.

    1997-09-01

    The working group meeting was chaired by Bauer and Lucas.Testing is a vital part of any cold source development project. This applies to specific physics concept verification, benchmarking in conjunction with computer modeling and engineering testing to confirm the functional viability of a proposed system. Irradiation testing of materials will always be needed to continuously extend a comprehensive and reliable information database. An ever increasing worldwide effort to enhance the performance of reactor and accelerator based neutron sources, coupled with the complexity and rising cost of building new generation facilities, gives a new dimension to cold source development and testing programs. A stronger focus is now being placed on the fine-tuning of cold source design to maximize its effectiveness in fully exploiting the facility. In this context, pulsed spallation neutron sources pose an extra challenge due to requirements regarding pulse width and shape which result from a large variety of different instrument concepts. The working group reviewed these requirements in terms of their consequences on the needs for testing equipment and compiled a list of existing and proposed facilities suitable to carry out the necessary development work.

  20. Aerobic methanotrophic bacteria of cold ecosystems.

    Science.gov (United States)

    Trotsenko, Yuri A; Khmelenina, Valentina N

    2005-06-01

    This review summarizes the recent advances in understanding the ecophysiological role and structure-function features of methanotrophic bacteria living in various cold ecosystems. The occurrence of methanotrophs in a majority of psychrosphere sites was verified by direct measurement of their methane-utilizing activity, by electron microscopy and immunofluorescent observations, and analyses of specific signatures in cellular phospholipids and total DNAs extracted from environmental samples. Surprisingly, the phenotypic and genotypic markers of virtually all extant methanotrophs were detected in various cold habitats, such as underground waters, Northern taiga and tundra soils, polar lakes and permafrost sediments. Also, recent findings indicated that even after long-term storage in permafrost, some methanotrophs can oxidize and assimilate methane not only at positive but also at subzero temperatures. Pure cultures of psychrophilic and psychrotolerant methanotrophs were isolated and characterized as new genera and species: Methylobacter psychrophilus, Methylosphaera hansonii, Methylocella palustris, Methylocella silvestris, Methylocella tundrae, Methylocapsa acidiphila and Methylomonas scandinavica. However, our knowledge about their adaptive mechanisms and survival in cold ecosystems remains limited and needs to be established using both traditional and molecular microbiological methods.