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Sample records for air fall deposits

  1. An Appalachian isochron: a kaolinized Carboniferous air-fall volcanic-ash deposit (tonstein)

    USGS Publications Warehouse

    Lyons, P.C.

    1992-01-01

    The Fire Clay tonstein is a kaolinized, airfall volcanic ash bed that was deposited in a widespread late Carboniferous peat-forming mire. Eleven samples from Kentucky and West Virginia, spanning a distance of 200km, and two samples from Tennessee and Virginia indicate a characteristic mineralogical signature. A high-silica alkalic rhyolitic source is suggested by the geochemistry of immobile elements and by electron-probe analyses of glass inclusions. 40Ar/39Ar sanidine plateau dating indicates an age of 312??1 Ma for the Fire Clay tonstein, which is consistent with previous 40Ar/39Ar dates for this tonstein. A new isopachous map of the Fire Clay ash-fall deposit indicates an area of 37 000km2 and a probable source to the present-day southwest. -from Authors

  2. Lessons from Popocatepetl Volcano (Mexico): Ancient Settlement Buried by Lavas, Mudflows, and Air-Fall Deposits

    NASA Technical Reports Server (NTRS)

    Delgado, H.; Panfil, M.; Gonzalez, E. A.; Coyoacan, C. U.; Urangaela, G.; Plunket, P.; Gardner, T.; Abrams, M.

    1994-01-01

    Popocatepetl volcano is 5452 m in altitude and capped by glaciers with a long Late Pleistocene-Holocene history. Volcanic activity has been intense during the last 10 000 years. Therefore, the valleys at the NE foothills of the volcano, covered by air-fall ejecta and drained by the runoff of the glaciers, became very attractive to ancient inhabitants of the Xalizintla Valley (XV) west of Puebla City, because of fertility of soils. The XV was occupied by humans about 2000 years ago who witnessed five events related to volcanic activity related to Popo. These events, described in this paper, are being taken into account for volcanic risk evaluation since several towns with a population of more than 23 000 people reoccupied again the Xalizintla Valley.

  3. Variations in welding characteristics within the Plinian air-fall deposit of the Middle Pumice eruption, Santorini, Greece

    NASA Astrophysics Data System (ADS)

    Boyce, Julie Ann; Gertisser, Ralf

    2012-04-01

    The welded Plinian air-fall deposit of the Middle Pumice A (MP-A) eruption, Santorini, Greece (144.6 ka), was analysed in order to document welding characteristics and determine the factors that control welding due to the sintering of hot ash- to block-sized pyroclasts. There are vertical and lateral variations in welding intensity, with welding increasing upwards within deposit sections and decreasing laterally away from the source. Four welding grades are distinguished: a = densely-welded, b = slightly-welded, c = tack-welded, and d = non-welded. Lateral welding zones are defined by the highest welding grade observed: zone A = densely-welded (< 0.25 km from the source); zone B = slightly-welded (0.25-1.26 km); zone C = tack-welded (1.26-3.7 km), and zone D = non-welded (> 3.7 km). Pumice density increases (and porosity decreases) with welding, with the most densely-welded part having a density of 2290 kg m- 3 and a porosity of 5%. Distal, non-welded pumices have a density of 370 kg m- 3 and porosities of > 75%. Clast oblateness varies from 0.79 in the densely-welded proximal deposit sections to 0.54 in the distal, non-welded deposits in southern Thera. Strain, determined using the Rf/ϕ method, indicates that the deposit is moderately flattened but relatively undeformed. The MP-A deposit is dacitic to andesitic in composition, becoming more mafic with stratigraphic height, where the degree of welding is highest. Welding is controlled by geochemical variations, compactional load and local variations in accumulation rate and clast sizes.

  4. Hybrid fall deposits in the Bishop Tuff, California: A novel pyroclastic depositional mechanism

    USGS Publications Warehouse

    Wilson, C.J.N.; Hildreth, W.

    1998-01-01

    Hybrid fall deposits in the Bishop Tuff show features common to both archetypal fall and surge deposits. Like normal-fall deposits, they have an overall plane-parallel bedding and flat-lying pumice clasts but also, like surge deposits, they show variable development of cross-bedding, some crystal and pumice sorting, and some rounding of pumice clasts. All variations exist from normal-fall deposits, through streaky material with incipient development of cross-bedding, to the hybrid fall deposits with well-developed cross-bedding. The streaky and hybrid deposits are interpreted as fall material contemporaneously redeposited by strong (up to 40 m/s) swirling winds, comparable to firestorm whirlwinds, generated by air currents associated with coeval emplacement of pyroclastic flows. Recognition of hybrid fall deposits is important in interpreting the dynamics of explosive eruptions and correctly assessing volcanic hazards. However, although such deposits may be commonly produced by explosive eruptions, especially where pyroclastic flows accompany fall activity, they are likely to be overlooked, or wrongly interpreted as surge deposits or secondary, reworked material.

  5. Bodies Falling with Air Resistance: Computer Simulation.

    ERIC Educational Resources Information Center

    Vest, Floyd

    1982-01-01

    Two models are presented. The first assumes that air resistance is proportional to the velocity of the falling body. The second assumes that air resistance is proportional to the square of the velocity. A program written in BASIC that simulates the second model is presented. (MP)

  6. Air Resistance on Falling Balls and Balloons

    NASA Astrophysics Data System (ADS)

    Gluck, Paul

    2003-03-01

    Studying the effect of air resistance on falling objects in an introductory mechanics course has the merit of relevance to a considerable part of our everyday experience: Leaves, parachutes, raindrops, or soot particles do not keep accelerating as they fall. This topic has been discussed in this and other journals many times,1-7 ranging from theoretical treatments to various experimental investigations, mostly for coffee filters, depending on the apparatus at the disposal of the writers (video clips, graphic calculators, and so on). We report here a sequence of activities for our 11th-grade high school students dealing with this topic. The analysis of data emphasizes points that do not seem to have been done in previous articles.

  7. When Does Air Resistance Become Significant in Free Fall?

    NASA Astrophysics Data System (ADS)

    Mohazzabi, Pirooz

    2011-02-01

    In introductory physics laboratories, students who experiment with freely falling objects frequently attribute any error in their experimental results to the presence of air resistance. It is, therefore, important to realize when and at what point during a free fall air resistance begins to play a significant role in the motion of the falling object. In this paper we address this question, and we show that blaming air resistance for errors in free-fall experiments in introductory physics laboratories is almost never justified.

  8. Uranium deposits in Fall River County, South Dakota

    USGS Publications Warehouse

    Bell, Henry; Bales, W.E.

    1954-01-01

    In 1951 uranium deposits contained carnotite were discovered in the southern Black Hills near Edgemont, Fall River County, S. Dak. Numerous carnotite deposits have since been found in sandstones in the Inyan Kara group of early Cretaceous age, and uranium-bearing material has been discovered in the Pennsylvania Minnelusa sandstone of Pennsylvanian age and the Deadwood formation of Cambrian age in the southern Black Hills. Ore has been produced only from the Inyan Kara group, mostly within an area of about 30 square miles along the southwest flank of the Black Hills uplift between Dewey and Hot Springs in Custer and Fall River Counties. In addition, occurrences of uranium in other parts of the Black Hills and the surrounding area are known or reported from sedimentary, igneous, and metamorphic rocks of pre-Cambrian to Tertiary age. The upper and lowermost formations of the Inyan Kara group - the Fall River and Lakota sandstones - contain the productive uranium deposits. These terrestrial formations are composed predominantly of massive sandstone lenses within units of thinly bedded sandstone and mudstone, but locally these formations contain abundant mudstone and thinly bedded sandstone. Massive sandstone lenses in the Lakota sandstone commonly overlap and truncate underlying lenses. The lenses are separated by thin units of thinly bedded sandstone and mudstone. Iron stain, carbonaceous material, thin seams of gypsum, ripple marks, concretions, and fossil roots are common in the mudstone and thinly bedded portions of these formations. Some high angle normal faults of small displacement are found in the area containing the largest number of uranium occurrences in the Inyan Kara group. Although no ore deposits seen were cut by faults, high-angle fractures parallel and at right angles to the faults contain carnotite for short distances. The productive uranium deposits are most common where the Fall River and Lakota sandstones locally contain a large proportion of

  9. Air compliance falls short without CEMs

    SciTech Connect

    Wagner, G.H. II

    1994-06-01

    Four titles of the Clean Air Act Amendments of 1990 refer to or require the use of continuous emission moniotrs (CEMs). The code of Federal regulations, Title 40, part 60, Appendix B lists the Performance Specifications for the design, installation and initial performance evaluation of CEMs. Emission monitors are required by 40 CFR 503 for sewage sludge incinerators and by 40 CFR 264/266 foir boilers and industrial furnaces. Technology advances of CEMs are discussed.

  10. Origin of reverse-graded bedding in air-fall pumice, Coso Range, California

    USGS Publications Warehouse

    Duffield, W.A.; Bacon, C.R.; Roquemore, G.R.

    1979-01-01

    The origin of reverse grading in air-fall pyroclastic deposits has been ascribed to: (1) changing conditions at an erupting vent; (2) deposition in water; or (3) rolling of large clasts over smaller clasts on the surface of a steep slope. Structural features in a deposit of air-fall pumice lapilli in the Coso Range, California, indicate that reverse grading there formed by a fourth mechanism during flow of pumice. Reverse-graded beds in this deposit occur where pumice lapilli fell on slopes at or near the angle of repose and formed as parts of the blanket of accumulating pumice became unstable and flowed downslope. The process of size sorting during such flow is probably analogous to that which sorts sand grains in a reverse fashion during avalanching on the slip faces of sand dunes, attributed by Bagnold (1954a) to a grain-dispersive pressure acting on particles subjected to a shear stress. In view of the several ways in which air-fall pyroclastic debris may become reverse graded, caution is advised in interpretation of the origin of this structure both in modern and in ancient deposits. ?? 1979.

  11. Deformation of a water shell during free fall in air

    NASA Astrophysics Data System (ADS)

    Nakoryakov, V. E.; Kuznetsov, G. V.; Strizhak, P. A.

    2016-04-01

    The basic regularities of the change in the shape and sizes (the initial volume is 0.05-0.5 L) of a water shell are singled out in its deformation during free fall in air from a height of 3 m. The 3D recording of the basic stages of deformation (flattening of the shell, nucleation, growth, and destruction of bubbles, formation of the droplet cloud) is carried out using high-speed (up to 105 frames per second) Phantom V411 and Phantom Miro M310 video cameras and the program complex Tema Automotive (with the function of continuous tracking). The physical model of destruction of large water bodies is formulated at free fall with the formation of the droplet cloud.

  12. The Sky is Falling: An air deposition/stormwater runoff model simulating the pathways of five heavy metals from their status as mobile and stack exhaust constituents to their delivery to the Elizabeth River

    SciTech Connect

    Barrett-McDaniels, J.; Barrett, M.

    1997-12-31

    Recent studies by the Environmental Protection Agency (EPA) indicate that air emissions contribute a major portion of the total loading of toxic metals to the waters of the Chesapeake Bay and its tributaries. According to the Chesapeake Executive Council of the interstate Chesapeake Bay Program, five of these metals, cadmium, chromium, copper, lead, and zinc, have been observed to have a negative impact on the waters of the Elizabeth River, which is within the Chesapeake Bay watershed. In order to better define the sources and processes which contribute to concentrations of these metals in the Elizabeth River, this analysis simulates the pathway of these metals from their status as mobile and stack exhaust constituents to their delivery to the river. EPA`s ISCST3 model was used to predict deposition loading on the Elizabeth River water and watershed surfaces, using regional annual meteorological data. Air emissions input to the ISCST3 model were derived from stationary and mobile sources: stationary source emissions were estimated using Virginia Department of Environmental Quality inventories and EPA-approved emissions factors for major sources with the potential to impact the watershed, while mobile source emissions were estimated using traffic volumes provided by the Department of Transportation and EPA-approved emissions factors. EPA`s SWMM model was then used to predict maximum short term and average annual build up and wash off rates for these metals using recorded rainfall data and existing land use and impervious cover for the watershed. The results are compared to water quality monitoring data from the municipal NPDES stormwater wet weather monitoring permit program.

  13. Disruption of tephra fall deposits caused by lava flows during basaltic eruptions

    NASA Astrophysics Data System (ADS)

    Brown, R. J.; Thordarson, T.; Self, S.; Blake, S.

    2015-10-01

    Observations in the USA, Iceland and Tenerife, Canary Islands reveal how processes occurring during basaltic eruptions can result in complex physical and stratigraphic relationships between lava and proximal tephra fall deposits around vents. Observations illustrate how basaltic lavas can disrupt, dissect (spatially and temporally) and alter sheet-form fall deposits. Complexity arises through synchronous and alternating effusive and explosive activity that results in intercalated lavas and tephra deposits. Tephra deposits can become disrupted into mounds and ridges by lateral and vertical displacement caused by movement (including inflation) of underlying pāhoehoe lavas and clastogenic lavas. Mounds of tephra can be rafted away over distances of 100 s to 1,000 s m from proximal pyroclastic constructs on top of lava flows. Draping of irregular topography by fall deposits and subsequent partial burial of topographic depressions by later lavas can result in apparent complexity of tephra layers. These processes, deduced from field relationships, have resulted in considerable stratigraphic complexity in the studied proximal regions where fallout was synchronous or alternated with inflation of subjacent lava sheets. These mechanisms may lead to diachronous contact relationships between fall deposits and lava flows. Such complexities may remain cryptic due to textural and geochemical quasi-homogeneity within sequences of interbedded basaltic fall deposits and lavas. The net effect of these processes may be to reduce the usefulness of data collected from proximal fall deposits for reconstructing basaltic eruption dynamics.

  14. Rock fall dynamics and deposition: an integrated analysis of the 2009 Ahwiyah Point rock fall, Yosemite National Park, USA.

    USGS Publications Warehouse

    Valerie L. Zimmer,; Collins, Brian; Greg M. Stock,; Nicholas Sitar,

    2012-01-01

    We analyzed a combination of airborne and terrestrial LiDAR, high-resolution photography, seismic, and acoustic data in order to gain insights into the initiation, dynamics, and talus deposition of a complex rock fall. A large (46 700 m3) rock fall originated from near Ahwiyah Point in eastern Yosemite Valley and fell a total of 730 m to the valley floor on 28 March 2009. Analyses of remote sensing, seismic, and acoustic data were integrated to reconstruct the rock fall, which consisted of (1) the triggering of a 25 400 m3 rock block in an area of intersecting and sometimes highly weathered joint planes, (2) the sliding and subsequent ballistic trajectory of the block from a steeply dipping ledge, (3) dislodging of additional rock from the cliff surface from beneath the rock fall source area, (4) a mid-cliff ledge impact that detached a volume of rock nearly equivalent in volume to the initial block, (5) sliding of the deteriorating rock mass down the remainder of the cliff, and (6) final impact at the base of the cliff that remobilized the existing talus downward and outward and produced an airblast that knocked down hundreds of trees. The depositional geomorphology indicates that the porosity of the fresh talus is significantly lower than that expected for typical blocky talus slopes, likely because the rock debris from this event was pulverized into smaller, more poorly sorted fragments and densified via dynamic compaction when compared to less energetic, fragmental-type rock falls. These results suggest that accumulation of individual rock-fall boulders tends to steepen talus slopes, whereas large, energetic rock falls tend to flatten them. Detachment and impact signals were recorded by seismic and acoustic instruments and highlight the potential use of this type of instrumentation for generalized rock fall monitoring, while LiDAR and photography data were able to quantify the cliff geometry, rock fall volume, source and impact locations, and

  15. Forensic recovery of transient eruption parameters for the 2360 BP fall deposit, Mount Meager, British Columbia

    NASA Astrophysics Data System (ADS)

    Campbell, Michelle E.; Porritt, Lucy; Russell, J. K.

    2016-02-01

    The 2360 BP eruption of Mount Meager, Canada featured an explosive subplinian onset resulting in dacitic fallout tephra and associated pumiceous pyroclastic flow deposits, followed by the effusion of dacite lava and the deposition of a thick sequence of block and ash flow deposits. Fall deposits are distributed to the NE of the vent onto a rugged, deeply incised landscape. The central axis of deposition is ~ 063° Az; the lateral margins of the fall deposit are massive to unbedded whereas deposits underlying the plume axis feature complex bedding relationships. We present componentry and granulometry data for eight outcroppings of the fall deposit (four on plume axis and four off plume axis). Vertical cross-sections, based on surface outcrops and drill core logs from local commercial drilling programs, are used to relate the accessory lithics to their source depth in the underlying subvolcanic basement. These combined datasets inform on the dynamics of this explosive phase of the eruption including variations in column height, eruption intensity, atmospheric conditions, and depth to fragmentation front. The lateral variations within the fall strata reflect the effects of the prevailing atmospheric conditions on the form and dispersal pattern of the subplinian plume. Vertical variations in granulometry and componentry of the fall deposits are used to track temporal changes in eruption intensity and column height and the transient influence of the jetstream on the dispersal pattern of the plume. Lastly, vertical variations in lithic componentry, combined with our knowledge of the subsurface geology, are used to quantitatively track the deepening of the fragmentation front. Our computed results show that the fragmentation front migrated from ~ 640 m to ~ 1160 m below the vent over the course of the 2360 BP Mount Meager eruption.

  16. Most recent fall deposits of Ksudach Volcano, Kamchatka, Russia

    NASA Technical Reports Server (NTRS)

    Bursik, M.; Melekestsev, I. V.; Brajtseva, O. A.

    1993-01-01

    Three of four Plinian eruptions from Ksudach Volcano are among the four largest explosive eruptions in southern Kamchatka during the past 2000 years. The earliest of the eruptions was voluminous and was accompanied by an ignimbrite and the fifth and most recent Cddera collapse event at Ksudach. The isopach pattern is consistent with a column height of 23 km. The three more recent and smaller eruptions were from the Shtyubel' Cone, within the fifth caldera. Using isopach and grain size isopleth patterns, column heights ranged from >10 to 22 kin. Although the oldest eruption may have produced a large acidity peak in the Greenland ice, the three Shtyubel' events may not be related to major acid deposition. Thus it is possible that few if any of the uncorrelated acidity peaks of the past 2000 years in Greenland ice cores result from eruptions in southern Kamchatka.

  17. Character, mass, distribution, and origin of tephra-fall deposits of the 1989-1990 eruption of redoubt volcano, south-central Alaska

    USGS Publications Warehouse

    Scott, W.E.; McGimsey, R.G.

    1994-01-01

    The 1989-1990 eruption of Redoubt Volcano spawned about 20 areally significant tephra-fall deposits between December 14, 1989 and April 26, 1990. Tephra plumes rose to altitudes of 7 to more than 10 km and were carried mainly northward and eastward by prevailing winds, where they substantially impacted air travel, commerce, and other activities. In comparison to notable eruptions of the recent past, the Redoubt events produced a modest amount of tephra-fall deposits - 6 ?? 107 to 5 ?? 1010 kg for individual events and a total volume (dense-rock equivalent) of about 3-5 ?? 107 m3 of andesite and dacite. Two contrasting tephra types were generated by these events. Pumiceous tephra-fall deposits of December 14 and 15 were followed on December 16 and all later events by fine-grained lithic-crystal tephra deposits, much of which fell as particle aggregates. The change in the character of the tephra-fall deposits reflects their fundamentally different modes of origin. The pumiceous deposits were produced by magmatically driven explosions. The finegrained lithic-crystal deposits were generated by two processes. Hydrovolcanic vent explosions generated tephrafall deposits of December 16 and 19. Such explosions continued as a tephra source, but apparently with diminishing importance, during events of January and February. Ash clouds of lithic pyroclastic flows generated by collapse of actively growing lava domes probably contributed to tephra-fall deposits of all events from January 2 to April 26, and were the sole source of tephra fall for at least the last 4 deposits. ?? 1994.

  18. Air density measurement with a falling A4 sheet

    NASA Astrophysics Data System (ADS)

    Oladyshkin, Ivan V.; Oladyshkina, Anastasia A.

    2016-09-01

    We propose a simple experiment on the air density measurement which does not require any special equipment: just an A4 sheet of paper, a stopwatch and a ruler. The discussed method uses the most basic air resistance model.

  19. Deposition velocity of caesium-137 on vertical building surfaces

    NASA Astrophysics Data System (ADS)

    Roed, Jørn

    Deposition of fall-out particles of caesium-137 on vertical building surfaces has been measured. The deposition is combined with the corresponding concentration in air of fall-out particles to give the deposition velocity.

  20. Late Quaternary distal tephra-fall deposits in lacustrine sediments, Kenai Peninsula, Alaska

    NASA Astrophysics Data System (ADS)

    de Fontaine, Christian S.; Kaufman, Darrell S.; Scott Anderson, R.; Werner, Al; Waythomas, Christopher F.; Brown, Thomas A.

    2007-07-01

    Tephra-fall deposits from Cook Inlet volcanoes were detected in sediment cores from Tustumena and Paradox Lakes, Kenai Peninsula, Alaska, using magnetic susceptibility and petrography. The ages of tephra layers were estimated using 21 14C ages on macrofossils. Tephras layers are typically fine, gray ash, 1-5 mm thick, and composed of varying proportions of glass shards, pumice, and glass-coated phenocrysts. Of the two lakes, Paradox Lake contained a higher frequency of tephra (0.8 tephra/100 yr; 109 over the 13,200-yr record). The unusually large number of tephra in this lake relative to others previously studied in the area is attributed to the lake's physiography, sedimentology, and limnology. The frequency of ash fall was not constant through the Holocene. In Paradox Lake, tephra layers are absent between ca. 800-2200, 3800-4800, and 9000-10,300 cal yr BP, despite continuously layered lacustrine sediment. In contrast, between 5000 and 9000 cal yr BP, an average of 1.7 tephra layers are present per 100 yr. The peak period of tephra fall (7000-9000 cal yr BP; 2.6 tephra/100 yr) in Paradox Lake is consistent with the increase in volcanism between 7000 and 9000 yr ago recorded in the Greenland ice cores.

  1. Late Quaternary distal tephra-fall deposits in lacustrine sediments, Kenai Peninsula, Alaska

    USGS Publications Warehouse

    de Fontaine, C.S.; Kaufman, D.S.; Scott, Anderson R.; Werner, A.; Waythomas, C.F.; Brown, T.A.

    2007-01-01

    Tephra-fall deposits from Cook Inlet volcanoes were detected in sediment cores from Tustumena and Paradox Lakes, Kenai Peninsula, Alaska, using magnetic susceptibility and petrography. The ages of tephra layers were estimated using 21 14C ages on macrofossils. Tephras layers are typically fine, gray ash, 1-5??mm thick, and composed of varying proportions of glass shards, pumice, and glass-coated phenocrysts. Of the two lakes, Paradox Lake contained a higher frequency of tephra (0.8 tephra/100 yr; 109 over the 13,200-yr record). The unusually large number of tephra in this lake relative to others previously studied in the area is attributed to the lake's physiography, sedimentology, and limnology. The frequency of ash fall was not constant through the Holocene. In Paradox Lake, tephra layers are absent between ca. 800-2200, 3800-4800, and 9000-10,300??cal yr BP, despite continuously layered lacustrine sediment. In contrast, between 5000 and 9000??cal yr BP, an average of 1.7 tephra layers are present per 100 yr. The peak period of tephra fall (7000-9000??cal yr BP; 2.6 tephra/100 yr) in Paradox Lake is consistent with the increase in volcanism between 7000 and 9000 yr ago recorded in the Greenland ice cores. ?? 2007 Elsevier Inc. All rights reserved.

  2. A new interpolation method to model thickness, isopachs, extent, and volume of tephra fall deposits

    NASA Astrophysics Data System (ADS)

    Yang, Qingyuan; Bursik, Marcus

    2016-10-01

    Tephra thickness distribution is the primary piece of information used to reconstruct the histories of past explosive volcanic eruptions. We present a method for modeling tephra thickness with less subjectivity than is the case with hand-drawn isopachs, the current, most frequently used method. The algorithm separates the thickness of a tephra fall deposit into a trend and local variations and models them separately using segmented linear regression and ordinary kriging. The distance to the source vent and downwind distance are used to characterize the trend model. The algorithm is applied to thickness datasets for the Fogo Member A and North Mono Bed 1 tephras. Simulations on subsets of data and cross-validation are implemented to test the effectiveness of the algorithm in the construction of the trend model and the model of local variations. The results indicate that model isopach maps and volume estimations are consistent with previous studies and point to some inconsistencies in hand-drawn maps and their interpretation. The most striking feature noticed in hand-drawn mapping is a lack of adherence to the data in drawing isopachs locally. Since the model assumes a stable wind field, divergences from the predicted decrease in thickness with distance are readily noticed. Hence, wind direction, although weak in the case of Fogo A, was not unidirectional during deposition. A combination of the isopach algorithm with a new, data transformation can be used to estimate the extent of fall deposits. A limitation of the algorithm is that one must estimate "by hand" the wind direction based on the thickness data.

  3. Spain as an emergency air traffic hub during volcanic air fall events? Evidence of past volcanic ash air fall over Europe during the late Pleistocene

    NASA Astrophysics Data System (ADS)

    Hardiman, Mark; Lane, Christine; Blockley, Simon P. E.; Moreno, Ana; Valero-Garcés, Blas; Ortiz, José E.; Torres, Trino; Lowe, John J.; Menzies, Martin A.

    2010-05-01

    Past volcanic eruptions often leave visible ash layers in the geological record, for example in marine or lake sedimentary sequences. Recent developments, however, have shown that non-visible volcanic ash layers are also commonly preserved in sedimentary deposits. These augment the record of past volcanic events by demonstrating that past ash dispersals have been more numerous and widely disseminated in Europe than previously appreciated. The dispersal ‘footprints' of some large late Pleistocene European eruptions are examined here in the light of the recent Eyjafjallajökull eruption. For example, the Vedde Ash which was erupted from Iceland around 12 thousand years ago, delivered distal (and non-visible) glass deposits as far south as Switzerland and as far east as the Ural Mountains in Russia, with an overall European distribution remarkably similar to the dominant tracks of the recent Eyjafjallajökull plumes. The Eyjafjallajökull eruption has demonstrated that relatively small amounts of distal volcanic ash in the atmosphere can seriously disrupt aviation activity, with attendant economic and other consequences. It has raised fundamental questions about the likelihood of larger or more prolonged volcanic activity in the near future, and the possibility of even more serious consequences than those experienced recently. Given that there are several other volcanic centres that could cause such disruption in Europe (e.g. Campania and other volcanic centres in Italy; Aegean volcanoes), a key question is whether there are parts of Europe less prone to ash plumes and which could therefore operate as emergency air traffic hubs during times of ash dispersal. Although not generated to answer this question, the recent geological record might provide a basis for seeking the answer. For example, four palaeo-records covering the time frame of 8 - 40 Ka BP that are geographically distributed across Spain have been examined for non-visible distal ash content. All four have

  4. Atmospheric transport and deposition of acidic air pollutants

    SciTech Connect

    Murphy, C.E. Jr.

    1981-01-01

    Although general principles which govern atmospheric chemistry of sulfur are understood, a purely theoretical estimation of the magnitude of the processes is not likely to be useful. Furthermore, the data base necessary to make empirical estimates does not yet exist. The sulfur budget of the atmosphere appears to be dominated by man-associated sulfur. The important processes in deposition of man-associated sulfur are wet deposition of sulfate and dry deposition of SO/sub 2/. The relative importance of sulfate and SO/sub 2/ to sulfur deposition (input to watersheds) depends on the air concentrations, and either compound may be the greater contributor depending on conditions. (PSB)

  5. Bioaerosol deposition on an air-conditioning cooling coil

    NASA Astrophysics Data System (ADS)

    Wu, Yan; Chen, Ailu; Luhung, Irvan; Gall, Elliott T.; Cao, Qingliang; Chang, Victor Wei-Chung; Nazaroff, William W.

    2016-11-01

    This study is concerned with the role of a fin-and-tube heat exchanger in modifying microbial indoor air quality. Specifically, depositional losses of ambient bioaerosols and particles onto dry (not cooled) and wet (cool) coil surfaces were measured for different airspeeds passing through the test coil. Total, bacterial and fungal DNA concentrations in condensate water produced by a wet coil were also quantified by means of fluorescent dsDNA-binding dye and qPCR assays. Results revealed that the deposition of bioaerosols and total particles is substantial on coil surfaces, especially when wet and cool. The average deposition fraction was 0.14 for total DNA, 0.18 for bacterial DNA and 0.22 for fungal DNA on the dry coil, increasing to 0.51 for total DNA, 0.50 for bacterial DNA and 0.68 for fungal DNA on the wet coil. Overall, as expected, deposition fractions increased with increasing particle size and increasing airspeed. Deposited DNA was removed from the cooling coil surfaces through the flow of condensing water at a rate comparable to the rate of direct deposition from air. A downward trend of bacterial and fungal DNA measured in condensate water over time provides suggestive evidence of biological growth on heat exchangers during nonoperational times of a ventilation system. This investigation provides new information about bioaerosol deposition onto a conventional fin-and-tube cooling coil, a potentially important factor influencing indoor exposure to microbial aerosols in air-conditioned buildings.

  6. Fall 1994 wildlife and vegetation survey, Norton Air Force Base, California

    SciTech Connect

    Not Available

    1994-12-15

    The fall 1994 wildlife and vegetation surveys were completed October 3-7, 1994, at Norton Air Force Base (AFB), California. Two biologists from CDM Federal Programs, the U.S. Environmental Protection Agency (EPA) regional biologist and the Oak Ridge National Laboratory (ORNL) lead biologist conducted the surveys. A habitat assessment of three Installation Restoration Project (IRP) sites at Norton Air Force Base was also completed during the fall survey period. The IRP sites include: Landfill No. 2 (Site 2); the Industrial Wastewater Treatment Plant (IWTP) area; and Former Fire Training Area No. 1 (Site 5). The assessments were designed to qualitatively characterize the sites of concern, identify potential ecological receptors, and provide information for Remedial Design/Remedial Action activities. A Reference Area (Santa Ana River Wash) and the base urban areas were also characterized. The reference area assessment was performed to provide a baseline for comparison with the IRP site habitats. The fall 1994 survey is the second of up to four surveys that may be completed. In order to develop a complete understanding of all plant and animal species using the base, these surveys were planned to be conducted over four seasons. Species composition can vary widely during the course of a year in Southern California, and therefore, seasonal surveys will provide the most complete and reliable data to address changes in habitat structure and wildlife use of the site. Subsequent surveys will focus on seasonal wildlife observations and a spring vegetation survey.

  7. A Photographic Study of Freezing of Water Droplets Falling Freely in Air

    NASA Technical Reports Server (NTRS)

    Dorsch, Robert G.; Levine, Joseph

    1952-01-01

    A photographic technique for investigating water droplets of diameter less than 200 microns falling freely in air at temperatures between 0 C and -50 C has been devised and used to determine: (i) The shape of frozen droplets (2) The occurrence of collisions of partly frozen or of frozen and liquid droplets (3) The statistics on the freezing temperatures of individual free-falling droplets A considerable number of droplets were found to have a nonspherical shape after freezing because of various protuberances and frost growth, and droplet aggregates formed by collision. The observed frequency of collision of partly frozen droplets showed good order of magnitude agreement with the frequency computed from theoretical collection efficiencies. The freezing temperature statistics indicated a general similarity of the data to those obtained for droplets frozen on a metallic surface in previous experiments.

  8. Aerosols Generated by Free Fall Spills of Powders and Solutions in Static Air

    SciTech Connect

    Sutter, S. L.; Johnston, J. W.; Mishima, J.

    1981-12-01

    Safety assessments and environmental impact statements for nuclear fuel cycle facilities require an estimation of potential airborne releases. Aerosols generated by accidents are being investigated to develop the source terms for these releases. The lower boundary accidental release event would be a free fall spill of powders or liquids in static air. Experiments measured the mass airborne and particle size distribution of these aerosols for various source sizes and spill heights. Two powder and liquid sources were used: Ti02 and uo2; and aqueous uranine (sodium fluorescein) and uranyl nitrate solutions. Spill height and source size were significant in releases of both powders and liquids. For the source powders used (l "m uo2 and 1.7 "m Ti0 2, quantities from 25 g to 1000 g, and fall heights of 1 m and 3m), the maximum source airborne was 0.12%. The maximum source airborne was an order of magnitude less for the liquids (with source quantities ranging from 125 to 1000 cc at the same fall heights). The median aerodynamic equivalent diameters for collected airborne powder ranged from 6 to 26.5 "m; liquids ranged from 4.1 to 34 "m. All of the spills produced a significant fraction of respirable particles 10 ~m and less.

  9. Use of dust fall filters as passive samplers for metal concentrations in air for communities near contaminated mine tailings

    PubMed Central

    Beamer, P.I.; Sugeng, A. J.; Kelly, M.D.; Lothrop, N.; Klimecki, W.; Wilkinson, S.T.; Loh, M.

    2014-01-01

    Mine tailings are a source of metal exposures in many rural communities. Multiple air samples are necessary to assess the extent of exposures and factors contributing to these exposures. However, air sampling equipment is costly and requires trained personnel to obtain measurements, limiting the number of samples that can be collected. Simple, low-cost methods are needed to allow for increased sample collection. The objective of our study was to assess if dust fall filters can serve as passive air samplers and be used to characterize potential exposures in a community near contaminated mine tailings. We placed filters in cylinders, concurrently with active indoor air samplers, in 10 occupied homes. We calculated an estimated flow rate by dividing the mass on each dust fall filter by the bulk air concentration and the sampling duration. The mean estimated flow rate for dust fall filters was significantly different during sampling periods with precipitation. The estimated flow rate was used to estimate metal concentration in the air of these homes, as well as in 31 additional homes in another rural community impacted by contaminated mine tailings. The estimated air concentrations had a significant linear association with the measured air concentrations for beryllium, manganese and arsenic (p<0.05), whose primary source in indoor air is resuspended soil from outdoors. In the second rural community, our estimated metal concentrations in air were comparable to active air sampling measurements taken previously. This passive air sampler is a simple low-cost method to assess potential exposures near contaminated mining sites. PMID:24469149

  10. Effect of backyard burning on dioxin deposition and air concentrations.

    PubMed

    Wevers, M; De Fré, R; Desmedt, M

    2004-03-01

    The influence from open burning of garden and household waste on locally measured dioxin deposition and air concentrations was evaluated in three sets of experiments: the combustion of garden waste in barrels and in open fires, and the incineration of household waste in an empty oil drum. Each set was composed of eight individual experiments over 4 h. Deposition gauges were located 20 m NE, SE, SW and NW with respect to the source and on a background location at 400 m SW. Air samples were taken in the plume with a medium volume sampler equipped with a quartz filter and a polyurethane plug. The results illustrate deposition increments in the wind direction at a distance of 20 m from the source of 0.8 pg TEQ/m2 day for garden waste and 2.5 pg TEQ/m2 day for household waste. Concentrations in the plume were increased by 160-580 fg TEQ/m3 over a period of 12 and 31 h respectively. Expressed at a reference CO2 concentration of 9% this corresponds with a range from 0.8 to 3.6 ng TEQ/m3, which is comparable with a poorly controlled MSWI. Emission factors in the order of magnitude of 4.5 ng TEQ/kg combusted garden waste and 35 ng TEQ/kg burned municipal waste were determined.

  11. Ambient Air Sampling During Quantum-dot Spray Deposition

    SciTech Connect

    Jankovic, John Timothy; Hollenbeck, Scott M

    2010-01-01

    Ambient air sampling for nano-size particle emissions was performed during spot spray coating operations with a Sono-Tek Exactacoat Benchtop system (ECB). The ECB consisted of the application equipment contained within an exhaust enclosure. The enclosure contained numerous small access openings, including an exhaust hook-up. Door access comprised most of the width and height of the front. The door itself was of the swing-out type. Two types of nanomaterials, Cadmium selenide (Cd-Se) quantum-dots (QDs) and Gold (Au) QDs, nominally 3.3 and 5 nm in diameter respectively, were applied during the evaluation. Median spray drop size was in the 20 to 60 micrometer size range.1 Surface coating tests were of short duration, on the order of one-half second per spray and ten spray applications between door openings. The enclosure was ventilated by connection to a high efficiency particulate aerosol (HEPA) filtered house exhaust system. The exhaust rate was nominally 80 ft3 per minute producing about 5 air changes per minute. Real time air monitoring with a scanning mobility particle size analyzer (SMPS ) with a size detection limit of 7 nm indicated a significant increase in the ambient air concentration upon early door opening. A handheld condensation particle counter (CPC) with a lower size limit of 10 nm did not record changes in the ambient background. This increase in the ambient was not observed when door opening was delayed for 2 minutes (~10 air changes). The ventilated enclosure controlled emissions except for cases of rapid door opening before the overspray could be removed by the exhaust. A time delay sufficient to provide 10 enclosure air changes (a concentration reduction of more than 99.99 %) before door opening prevented the release of aerosol particles in any size.2 Scanning-transmission electron microscopy (STEM) and atomic force microscopy (AFM) demonstrated the presence of agglomerates in the surfaces of the spray applied deposition. A filtered air sample of

  12. Eruption dynamics of the 22-23 April 2015 Calbuco Volcano (Southern Chile): Analyses of tephra fall deposits

    NASA Astrophysics Data System (ADS)

    Romero, J. E.; Morgavi, D.; Arzilli, F.; Daga, R.; Caselli, A.; Reckziegel, F.; Viramonte, J.; Díaz-Alvarado, J.; Polacci, M.; Burton, M.; Perugini, D.

    2016-05-01

    After 54 years since its last major eruption in 1961, Calbuco Volcano (Ensenada, Southern Chile) reawakened with few hours of warning on 22 April 2015 at 18:05 local time. The main explosive eruption consisted of two eruption pulses (lasting 1.5 and 6 h each one) on 22 and 23 April, producing stratospheric (> 15 km height) eruption columns. The erupted materials correspond to porphyritic basaltic andesite ( 55 wt.% of SiO2). The tephra fall affected mainly the area northeast of the volcano and the finest ash was deposited over Southern Chile and Patagonia Argentina. We studied the tephra fall deposits of both pulses in terms of stratigraphy, distribution, volume, emplacement dynamics and eruption source parameters. Here, we show field observations that have been made 5-470 km downwind and distinguish five layers (Layers A, B, B1, C and D) representing different stages of the eruption evolution: eruption onset (Layer A; pulse 1), followed by the first paroxysmal event (Layer B; pulse 1), in some places interbedded by layer B1, tentatively representing the sedimentation of a secondary plume during the end of pulse 1. We recognized a second paroxysm (Layer C; pulse 2) followed by the waning of the eruption (Layer D; pulse 2). The total calculated bulk tephra fall deposit volume is 0.27 ± 0.007 km3 (0.11-0.13 km3 dense rock equivalent), 38% of which was erupted during the first phase and 62% during the second pulse. This eruption was a magnitude 4.45 event (VEI 4 eruption) of subPlinian type.

  13. Calbuco volcano (Southern Chile) Eruption 22-23 April 2015: pyroclastic fall deposits and preliminary petrological study

    NASA Astrophysics Data System (ADS)

    Morgavi, Daniele; Romero, Jorge; Arzilli, Fabio; Daga, Romina; Caselli, Alberto; Reckziegel, Florencia; Viramonte, Jose; Polacci, Margherita; Burton, Mike; Perugini, Diego

    2016-04-01

    After 54 years since its last major eruption in 1961, Calbuco volcano (Ensenada, Southern Chile) reawakened with few hours of warning on 22 April 2015 at 18:05 local time. The main explosive eruption consisted of two eruption pulses (lasting ~1.5 and ~6 hours each one) on 22 and 23 April, producing stratospheric (>15 km height) eruption columns. The tephra fall affected mainly the area northeast of the volcano and the finest ash was deposited over Southern Chile and Patagonia Argentina. We studied the tephra fall deposits of both pulses in terms of stratigraphy, distribution, volume, emplacement dynamics and eruption source parameters. Here, we show field observations made from 5 to 470 km downwind and we distinguish five layers (Layers A, B, B1, C and D) representing different stages of the eruption evolution. The total calculated bulk tephra fall deposit volume is 0.27±0.007 km3 (0.11-0.13 km3 dense rock equivalent). The 38% of it was erupted during the first phase and 62% during the second pulse. This eruption was a magnitude 4.45 event (VEI 4 eruption) of Subplinian type. The erupted materials correspond to a porphyritic basaltic-andesite (54.40-57.2 wt. of % SiO2). It produced two types of pumice clasts: high density pumice (HDP), poorly vesiculated and crystal-rich (up to 40 % crystals by volume), and lower density pumice (LDP) characterized by a slightly lower crystallinity and higher vesicle fraction. The textures include phenocrysts in a glassy groundmass with a minor presence of microlites. The mineralogical assemblage of pumices consists of plagioclase (Pl), orthopyroxene (Opx), clinopyroxene (Cpx), Ti-magnetite, and sanidine (Sa) as accessory mineral.

  14. Eruption dynamics of the 22-23 April 2015 Calbuco Volcano (Southern Chile): Analyses of tephra fall deposits

    NASA Astrophysics Data System (ADS)

    Romero, J. E.; Morgavi, D.; Arzilli, F.; Daga, R.; Caselli, A.; Reckziegel, F.; Viramonte, J.; Díaz-Alvarado, J.; Polacci, M.; Burton, M.; Perugini, D.

    2016-05-01

    After 54 years since its last major eruption in 1961, Calbuco Volcano (Ensenada, Southern Chile) reawakened with few hours of warning on 22 April 2015 at 18:05 local time. The main explosive eruption consisted of two eruption pulses (lasting ~ 1.5 and 6 h each one) on 22 and 23 April, producing stratospheric (> 15 km height) eruption columns. The erupted materials correspond to porphyritic basaltic andesite (~ 55 wt.% of SiO2). The tephra fall affected mainly the area northeast of the volcano and the finest ash was deposited over Southern Chile and Patagonia Argentina. We studied the tephra fall deposits of both pulses in terms of stratigraphy, distribution, volume, emplacement dynamics and eruption source parameters. Here, we show field observations that have been made 5-470 km downwind and distinguish five layers (Layers A, B, B1, C and D) representing different stages of the eruption evolution: eruption onset (Layer A; pulse 1), followed by the first paroxysmal event (Layer B; pulse 1), in some places interbedded by layer B1, tentatively representing the sedimentation of a secondary plume during the end of pulse 1. We recognized a second paroxysm (Layer C; pulse 2) followed by the waning of the eruption (Layer D; pulse 2). The total calculated bulk tephra fall deposit volume is 0.27 ± 0.007 km3 (0.11-0.13 km3 dense rock equivalent), 38% of which was erupted during the first phase and 62% during the second pulse. This eruption was a magnitude 4.45 event (VEI 4 eruption) of subPlinian type.

  15. Evaluation of a low-cost electrostatic dust fall collector for indoor air endotoxin exposure assessment.

    PubMed

    Noss, Ilka; Wouters, Inge M; Visser, Maaike; Heederik, Dick J J; Thorne, Peter S; Brunekreef, Bert; Doekes, Gert

    2008-09-01

    Exposure to endotoxin in home environments has become a key issue in asthma and allergy research. Most studies have analyzed floor or mattress dust endotoxin, but its validity as a proxy for airborne exposure is unknown, while active airborne dust sampling is not feasible in large-scale population studies because of logistic and financial limitations. We therefore developed and evaluated a simple passive airborne dust collection method for airborne endotoxin exposure assessment. We explored an electrostatic dust fall collector (EDC), consisting of a 42- by 29.6-cm-sized folder with four electrostatic cloths exposed to the air. The EDC was tested during two 14-day periods in seven nonfarm and nine farm homes and in farm stables. In parallel, active airborne dust sampling was performed with Harvard impactors and floor dust collected by vacuuming, using nylon sampling socks. The endotoxin levels could be measured in all EDC cloth extracts. The levels (in EU/m(2)) between EDCs used simultaneously or in different sampling periods in the same home correlated strongly (r > 0.8). EDC endotoxin also correlated moderately to strongly (r = 0.6 to 0.8) with the endotoxin measured by active airborne dust sampling and living room floor dust sampling and-in farm homes-with the endotoxin captured by the EDC in stables. In contrast, endotoxin levels measured by floor dust sampling showed only a poor correlation with the levels measured by active airborne dust sampling. We therefore conclude that measuring endotoxin levels with the EDC is a valid measure of average airborne endotoxin exposure, while reproducibility over time is at least equivalent to that of reservoir dust analyses.

  16. The 1815 Tambora ash fall: implications for transport and deposition of distal ash on land and in the deep sea

    NASA Astrophysics Data System (ADS)

    Kandlbauer, Jessica; Carey, Steven N.; Sparks, R. Stephen J.

    2013-04-01

    Tambora volcano lies on the Sanggar Peninsula of Sumbawa Island in the Indonesian archipelago. During the great 1815 explosive eruption, the majority of the erupted pyroclastic material was dispersed and subsequently deposited into the Indian Ocean and Java Sea. This study focuses on the grain size distribution of distal 1815 Tambora ash deposited in the deep sea compared to ash fallen on land. Grain size distribution is an important factor in assessing potential risks to aviation and human health, and provides additional information about the ash transport mechanisms within volcanic umbrella clouds. Grain size analysis was performed using high precision laser diffraction for a particle range of 0.2 μm-2 mm diameter. The results indicate that the deep-sea samples provide a smooth transition to the land samples in terms of grain size distributions despite the different depositional environments. Even the very fine ash fraction (<10 μm) is deposited in the deep sea, suggesting vertical density currents as a fast and effective means of transport to the seafloor. The measured grain size distribution is consistent with an improved atmospheric gravity current sedimentation model that takes into account the finite duration of an eruption. In this model, the eruption time and particle fall velocity are the critical parameters for assessing the ash component depositing while the cloud advances versus the ash component depositing once the eruption terminates. With the historical data on eruption duration (maximum 24 h) and volumetric flow rate of the umbrella cloud (˜1.5-2.5 × 1011 m3/s) as input to the improved model, and assuming a combination of 3 h Plinian phase and 21 h co-ignimbrite phase, it reduces the mean deviation of the predicted versus observed grain size distribution by more than half (˜9.4 % to ˜3.7 %) if both ash components are considered.

  17. Deposition and generation of multiple widespread fall units from the c. AD 1314 Kaharoa rhyolitic eruption, Tarawera, New Zealand

    NASA Astrophysics Data System (ADS)

    Sahetapy-Engel, Steve; Self, Stephen; Carey, Rebecca J.; Nairn, Ian A.

    2014-08-01

    The c. AD 1314 Kaharoa eruption from Tarawera volcano, North Island, New Zealand, was a complex, long-duration, multi-episode rhyolitic event. Up to 13 discrete sub-Plinian to Plinian-style phases occurred in two stages from at least two different vents along an 8-km-long fissure. The early explosive stage produced seven pumice lapilli fall units dispersed solely to the southeast of the volcano, while a later stage produced six fall units dispersed almost entirely to the north and northwest. The duration of fallout for these 13 lapilli units is estimated to have totaled about 1.5 days. The presence of massive-textured ash layers between many of the lapilli fall units suggests that longer-duration, pyroclastic density-current producing phases and more quiescent fallout intervals occurred between the intense explosive phases of the eruption (total duration of ash fallout ~ 7.5 days). The ash deposition extended the minimum duration of the explosive episodes to at least 9 days, based on settling rates of the ash. Possibly the explosive phase of eruptive activity lasted for ~ 2 weeks, including some brief hiatuses and pyroclastic density-current deposition, and was followed by ~ 4 years of mainly lava-dome-forming activity. At least 15 km3 (> 7.3 km3 dense rock equivalent, DRE) of tephra was erupted during the main explosive episodes, and at least 9.1 km3 DRE during the whole eruption, more than doubling the previous estimate. This may be an underestimate by up to 50 % of the fallout volume. Eruption column heights for the two most widely dispersed fall units are estimated to have ranged from 25-28 km above the vents and durations of individual lapilli fall unit-forming phases ranged from 1.5 to 4 h, but the ash-producing phases lasted much longer (individually up to 30 h) and represent a longer-lived shut-down to each eruptive episode. Time-averaged mass discharge rates are estimated to have varied by more than one order of magnitude during the main Plinian

  18. Phreatomagmatic and phreatic fall and surge deposits from explosions at Kilauea volcano, Hawaii, 1790 a.d.: Keanakakoi Ash Member

    USGS Publications Warehouse

    McPhie, J.; Walker, G.P.L.; Christiansen, R.L.

    1990-01-01

    In or around 1790 a.d. an explosive eruption took place in the summit caldera of Kilauea shield volcano. A group of Hawaiian warriors close to the caldera at the time were killed by the effects of the explosions. The stratigraphy of pyroclastic deposits surrounding Kilauea (i.e., the Keanakakoi Ash Member) suggests that the explosions referred to in the historic record were the culmination of a prolonged hydrovolcanic eruption consisting of three main phases. The first phase was phreatomagmatic and generated well-bedded, fine fallout ash rich in glassy, variably vesiculated, juvenile magmatic and dense, lithic pyroclasts. The ash was mainly dispersed to the southwest of the caldera by the northeasterly trade winds. The second phase produced a Strombolian-style scoria fall deposit followed by phreatomagmatic ash similar to that of the first phase, though richer in accretionary lapilli and lithics. The third and culminating phase was phreatic and deposited lithic-rich lapilli and block fall layers, interbedded with cross-bedded surge deposits, and accretionary lapilli-rich, fine ash beds. These final explosions may have been responsible for the deaths of the warriors. The three phases were separated by quiescent spells during which the primary deposits were eroded and transported downwind in dunes migrating southwestward and locally excavated by fluvial runoff close to the rim. The entire hydrovolcanic eruption may have lasted for weeks or perhaps months. At around the same time, lava erupted from Kilauea's East Rift Zone and probably drained magma from the summit storage. The earliest descriptions of Kilauea (30 years after the Keanakakoi eruption) emphasize the great depth of the floor (300-500 m below the rim) and the presence of stepped ledges. It is therefore likely that the Keanakakoi explosions were deepseated within Kilauea, and that the vent rim was substantially lower than the caldera rim. The change from phreatomagmatic to phreatic phases may reflect the

  19. Transport, deposition, and liftoff in laboratory density currents composed of hot particles in air

    NASA Astrophysics Data System (ADS)

    Andrews, B. J.; Manga, M.

    2010-12-01

    Understanding the dynamics of transport, deposition, and air entrainment in pyroclastic density currents (PDCs) is required for accurate predictions of future current behaviors and interpretations of ancient deposits, but directly observing the interiors of natural PDCs is effectively impossible. We model PDCs with scaled, hot, particle-laden density currents generated in a 6 m long, 0.6 m wide, 1.8 m tall air-filled tank. Comparison of relevant scaling between our experiments and natural PDCs indicates that we are accurately capturing much of the dynamics of dilute PDCs: * Reynolds numbers of our experiments are lower than natural currents, 10^3 compared to 10^6, but still fully turbulent; * Densimetric and Thermal Richardson numbers are of O(1) in both natural and modeled currents; * Stokes and settling numbers for particles in the experiments fall within the expected range for natural PDCs. Conditions within the tank are monitored with temperature and humidity probes. Experiments are illuminated with sheet lighting, and recorded with high-definition video cameras. In general, currents have average velocities of 10-20 cm/s, initial thicknesses of 10-20 cm (although thickness greatly increases as currents entrain and expand air), and run out or lift off distances of 3-5 m. Large Kelvin-Helmholtz type eddies usually form along the top of the current immediately behind the head; these vortices are similar in size to the total current thickness. In currents that lift off, the distal current end typically retreats with time. Preliminary results suggest that lift off distance decreases with increasing thermal Richardson number. Analysis of turbulent structures indicates that the current heads are dominated by large coherent structures with length scales, L, comparable to the current thickness. Within 5-10 L of the current fronts, sequences of similar large eddies often occur. At greater distances behind the current fronts, turbulent structures become smaller and less

  20. Open Air Silicon Deposition by Atmospheric Pressure Plasma under Local Ambient Gas Control

    NASA Astrophysics Data System (ADS)

    Naito, Teruki; Konno, Nobuaki; Yoshida, Yukihisa

    2015-09-01

    In this paper, we report open air silicon (Si) deposition by combining a silane free Si deposition technology and a newly developed local ambient gas control technology. Recently, material processing in open air has been investigated intensively. While a variety of materials have been deposited, there were only few reports on Si deposition due to the susceptibility to contamination and the hazardous nature of source materials. Since Si deposition is one of the most important processes in device fabrication, we have developed open air silicon deposition technologies in BEANS project. For a clean and safe process, a local ambient gas control head was designed. Process gas leakage was prevented by local evacuation, and air contamination was shut out by inert curtain gas. By numerical and experimental investigations, a safe and clean process condition with air contamination less than 10 ppm was achieved. Si film was deposited in open air by atmospheric pressure plasma enhanced chemical transport under the local ambient gas control. The film was microcrystalline Si with the crystallite size of 17 nm, and the Hall mobility was 2.3 cm2/V .s. These properties were comparable to those of Si films deposited in a vacuum chamber. This research has been conducted as one of the research items of New Energy and Industrial Technology Development Organization ``BEANS'' project.

  1. Stratigraphy and depositional history of Coyote Creek-Miller Creek Trend, Lower Cretaceous Fall River formation, Powder River Basin, Wyoming

    SciTech Connect

    Ryer, T.A.; Gustason, E.R.

    1985-05-01

    The Coyote Creek-Miller Creek trend produces high-gravity, low-sulfur oil from a series of Fall River fields in an area generally characterized by west-southwestward monoclinal dip. The trend includes, from south to north, the Coyote Creek South, Coyote Creek, Donkey Creek, Kummerfeld, and Miller Creek fields. The Wood and West Moorcroft fields produce oil from very similar Fall River traps located several miles east and northeast, respectively, of Miller Creek. Only Donkey Creek includes structural closure; all of the other fields produce from purely stratigraphic traps. The reservoir sandstones are characterized by upward-fining sequences. These sequences locally replace and are generally easily distinguishable from two regionally correlative upward-coarsening sequences. Analyses of cores and nearby outcrops indicate that the upward-fining sequences accumulated on point bars of a meandering river; the upward-coarsening sequences were deposited on the fronts of northwestward-prograding deltas. Detailed mapping of the fluvial and delta-front facies demonstrates that the Coyote Creek-Miller Creek trend, together with the Wood and West Moorcroft fields, represents a meander-belt system that was contemporaneous with the younger of the two delta-front units. Each of the stratigraphic-type fields occurs at a convexity along the eastern edge of the irregularly shaped meander belt; each consists of numerous point bars. Clay plugs, which resulted from infilling of abandoned meander loops, were preferentially preserved along the margins of the meander belt, where they now serve as updip permeability barriers between the oil-bearing fluvial and water-wet delta-front sandstones.

  2. Navier-Stokes computations for water drops falling in air: intermediate Reynolds numbers

    NASA Astrophysics Data System (ADS)

    Pearlstein, Arne; Shiue, Min-Po; Feng, James

    2006-11-01

    We report Navier-Stokes computations, using a finite-element technique, of the steady descent of a deformable water drop through air. Variations in drop shape, internal circulation, and drag coefficient with Reynolds number are discussed in terms of simple physical mechanisms. Discrepancies between the computational results and the experimental data of Beard and Pruppacher, obtained in an open-return vertical wind tunnel, are interpreted in terms of scavenging from the polluted atmosphere of surfactants, as measured by Kawamura et al. in collected rainwater samples several hundred meters southeast of the wind-tunnel intake.

  3. The contribution from shipping emissions to air quality and acid deposition in Europe.

    PubMed

    Derwent, Richard G; Stevenson, David S; Doherty, Ruth M; Collins, William J; Sanderson, Michael G; Johnson, Colin E; Cofala, Janusz; Mechler, Reinhard; Amann, Markus; Dentener, Frank J

    2005-02-01

    A global three-dimensional Lagrangian chemistry-transport model STOCHEM is used to describe the European regional acid deposition and ozone air quality impacts along the Atlantic Ocean seaboard of Europe, from the SO2, NOx, VOCs and CO emissions from international shipping under conditions appropriate to the year 2000. Model-derived total sulfur deposition from international shipping reaches over 200 mg S m(-2) yr(-1) over the southwestern approaches to the British Isles and Brittany. The contribution from international shipping to surface ozone concentrations during the summertime, peaks at about 6 ppb over Ireland, Brittany and Portugal. Shipping emissions act as an external influence on acid deposition and ozone air quality within Europe and may require control actions in the future if strict deposition and air quality targets are to be met.

  4. Aerosol Deposition in the Human Respiratory Tract Breathing Air and 80:20 Heliox

    PubMed Central

    DARQUENNE, CHANTAL; PRISK, G. KIM

    2005-01-01

    Aerosol mixing resulting from turbulent flows is thought to be an important mechanism of deposition in the upper respiratory tract (URT). Since turbulence levels are a function of gas density, the use of a low density carrier gas would be expected to reduce deposition in the URT. We measured aerosol deposition in the respiratory tract of 8 healthy subjects using both air and heliox, a low density gas mixture containing 80% helium and 20% oxygen, as the carrier gas. The subjects breathed 0.5, 1, and 2 μm-diameter monodisperse polystyrene latex particles from a reservoir at a constant flow rate (~450 mL/sec) and tidal volume (~900 mL). Aerosol concentration and flow rate were measured at the mouth using a photometer and a pneumotachograph, respectively. Deposition was 17.0%, 20.3%, and 38.9% in air and 16.8%, 18.5%, and 36.9% in heliox for 0.5, 1, and 2 μm-diameter particles, respectively. There was a small but statistically significant decrease in deposition when using heliox compared to air for 1 and 2 μm-diameter particles (p < 0.05). While it could not be directly measured from these data, it is likely that when breathing heliox instead of air, deposition is reduced in the URT and increased in the small airways and alveoli. PMID:15625820

  5. Areal distribution, thickness, mass, volume, and grain size of tephra-fall deposits from the 1992 eruptions of Crater Peak vent, Mt. Spurr Volcano, Alaska

    USGS Publications Warehouse

    McGimsey, Robert G.; Neal, Christina A.; Riley, Colleen M.

    2001-01-01

    The Crater Peak flank vent of Mount Spurr volcano erupted June 27, August 18, and September 16- 17, 1992. The three eruptions were similar in intensity (vulcanian to subplinian eruption columns reaching up to 14 km Above Sea Level) and duration (3.5 to 4.0 hours) and produced tephra-fall deposits (12, 14, 15 x 10 6 m3 Dense Rock Equivalent [DRE]) discernible up to 1,000 km downwind. The June 27 ash cloud traveled north over the rugged, ice- and snow-covered Alaska Range. The August 18 ash cloud was carried southeastward over Anchorage, across Prince William Sound, and down the southeastern shoreline of the Gulf of Alaska. The September 16-17 ash plume was directed eastward over the Talkeetna and Wrangell mountains and into the Yukon Territory of Canada. Over 50 mass-per-unit-area (MPUA) samples were collected for each of the latter two fall deposits at distances ranging from about 2 km to 370 km downwind from the volcano. Only 10 (mostly proximal) samples were collected for the June fall deposit due to inaccessible terrain and funding constraints. MPUA data were plotted and contoured (isomass lines) to graphically display the distribution of each fall deposit. For the August and September eruptions, fallout was concentrated along a narrow (30 to 50 km wide) belt. The fallout was most concentrated (100,000 to greater than 250,000 g/m2) within about 80 km of the volcano. Secondary maxima occur at 200 km (2,620 g/m2) and 300 km (4,659 g/m2), respectively, down axis for the August and September deposits. The maxima contain bimodal grain size distributions (with peaks at 88.4 and 22.1 microns) indicating aggregation within the ash cloud. Combined tephra-volume for the 1992 Mount Spurr eruptions (41 x 10 6 m3 DRE) is comparable to that (tephra-fall only) of the 1989-90 eruptions of nearby Redoubt volcano (31-49 x 106 m3 DRE).

  6. High Mercury Wet Deposition at a "Clean Air" Site in Puerto Rico.

    PubMed

    Shanley, James B; Engle, Mark A; Scholl, Martha; Krabbenhoft, David P; Brunette, Robert; Olson, Mark L; Conroy, Mary E

    2015-10-20

    Atmospheric mercury deposition measurements are rare in tropical latitudes. Here we report on seven years (April 2005 to April 2012, with gaps) of wet Hg deposition measurements at a tropical wet forest in the Luquillo Mountains, northeastern Puerto Rico, U.S. Despite receiving unpolluted air off the Atlantic Ocean from northeasterly trade winds, during two complete years the site averaged 27.9 μg m(-2) yr(-1) wet Hg deposition, or about 30% more than Florida and the Gulf Coast, the highest deposition areas within the U.S. These high Hg deposition rates are driven in part by high rainfall, which averaged 2855 mm yr(-1). The volume-weighted mean Hg concentration was 9.8 ng L(-1), and was highest during summer and lowest during the winter dry season. Rainout of Hg (decreasing concentration with increasing rainfall depth) was minimal. The high Hg deposition was not supported by gaseous oxidized mercury (GOM) at ground level, which remained near global background concentrations (<10 pg m(-3)). Rather, a strong positive correlation between Hg concentrations and the maximum height of rain detected within clouds (echo tops) suggests that droplets in high convective cloud tops scavenge GOM from above the mixing layer. The high wet Hg deposition at this "clean air" site suggests that other tropical areas may be hotspots for Hg deposition as well.

  7. Atmospheric dry deposition in the vicinity of the Salton Sea, California - I: Air pollution and deposition in a desert environment

    USGS Publications Warehouse

    Alonso, R.; Bytnerowicz, A.; Boarman, W.I.

    2005-01-01

    Air pollutant concentrations and atmospheric dry deposition were monitored seasonally at the Salton Sea, southern California. Measurements of ozone (O 3), nitric acid vapor (HNO3), ammonia (NH3), nitric oxide (NO), nitrogen dioxide (NO2) and sulfur dioxide (SO 2) were performed using passive samplers. Deposition rates of NO 3-, NH4+, Cl-, SO 42-, Na+, K+ and Ca2+ to creosote bush branches and nylon filters as surrogate surfaces were determined for one-week long exposure periods. Maximum O3 values were recorded in spring with 24-h average values of 108.8 ??g m-3. Concentrations of NO and NO2 were low and within ranges of the non-urban areas in California (0.4-5.6 and 3.3-16.2 ??g m-3 ranges, respectively). Concentrations of HNO3 (2.0-6.7 ??g m-3) and NH 3 (6.4-15.7 ??g m-3) were elevated and above the levels typical for remote locations in California. Deposition rates of Cl-, SO42-, Na+, K+ and Ca2+ were related to the influence of sea spray or to suspended soil particles, and no strong enrichments caused by ions originated by human activities were detected. Dry deposition rates of NO3- and NH4+ were similar to values registered in areas where symptoms of nitrogen saturation and changes in species composition have been described. Deposition of nitrogenous compounds might be contributing to eutrophication processes at the Salton Sea. ?? 2005 Elsevier Ltd. All rights reserved.

  8. Radioisotope Deposition on Interior Building Surfaces: Air Flow and Surface Roughness Influences

    SciTech Connect

    Leonard, Bobby E

    2005-12-15

    Interior surface deposition effects of vaporized radioactive aerosols are important in understanding their behavior in accident conditions such as the Japanese nuclear laboratory accident in 1999 and the Chernobyl nuclear power plant accident in 1986, where entire communities had to be abandoned because of surface contamination, and the hopefully unlikelihood of a terrorist dirty nuclear bomb attack. Airborne radon progeny offers an opportunity to study radioisotope surface deposition. A significant annual lung cancer rate is also attributed to airborne radon progeny in the interior domestic environment. Surface deposition rates influence the airborne progeny levels. Here, we report extensive {sup 218}Po deposition rates over typical air change rates (ACHs) from 0.02 to 1.0 h{sup -1} for interior furnishings surfaces in a 0.283-m{sup 3} test chamber to supplement earlier reported deposition rates for interior wall, ceiling, and floor surfaces. In analyzing the deposition results from the different materials, it is found that they correlate in terms of roughness with relative static friction and aerodynamic shear stress. Extrapolation to perfectly smooth surfaces provides a good estimate of the Fick's law value. Contrary to prior radon analysis at higher air flow, where the Crump and Seinfeld (CS) turbulent deposition models seemed to fit, at low ACH below 0.5 h{sup -1} the deposition data found excellent agreement with a new Brownian diffusive deposition model for laminar flow. A composite model using the Brownian diffusive laminar flow and the CS turbulent flow models provides an excellent fit to all data. These results provide insight into contamination issues relative to other airborne radioisotopes, with the relative effects being dependent on the airborne contaminant particle sizes and their respective diffusion coefficients as seen in the two deposition models.

  9. Dry and wet deposition of 7Be, 210Pb and 137Cs in Monaco air during 1998-2010: seasonal variations of deposition fluxes.

    PubMed

    Pham, Mai K; Povinec, Pavel P; Nies, Hartmut; Betti, Maria

    2013-06-01

    Temporal variations of (7)Be, (210)Pb and (137)Cs activity concentrations in precipitation in Monaco from 1998 to 2010 showed that maxima of (7)Be and (210)Pb deposition fluxes coincide with the peaks of precipitation amounts observed in different months of a year, and most of (7)Be and (210)Pb was washout from the atmosphere by precipitation. The seasonal variations were not uniform from year to year, and the amount of precipitation controlled the deposition fluxes of (7)Be and (210)Pb, which was not the case for (137)Cs. The fractional deposition fluxes of (7)Be and (210)Pb in different seasons were in the order fall > spring > winter > summer, while the fractional amount of precipitation followed the order fall > winter > spring > summer. The fractional deposition fluxes of (137)Cs were found in the order spring > fall > summer > winter. The precipitation-normalized deposition fluxes of (7)Be, (210)Pb and (137)Cs were generally higher during summer. The highest (7)Be/(210)Pb activity ratio was observed in 2010, and the smallest one in 2001, following the influence of the modulation of cosmic rays on the production rates of (7)Be in the atmosphere by solar activity. Activity ratios of (7)Be/(210)Pb observed in winter and fall were generally higher than during summer and spring.

  10. Air-stable ink for scalable, high-throughput layer deposition

    DOEpatents

    Weil, Benjamin D; Connor, Stephen T; Cui, Yi

    2014-02-11

    A method for producing and depositing air-stable, easily decomposable, vulcanized ink on any of a wide range of substrates is disclosed. The ink enables high-volume production of optoelectronic and/or electronic devices using scalable production methods, such as roll-to-roll transfer, fast rolling processes, and the like.

  11. Influence of subaqueous shelf angle on coastal plain-shelf-slope deposits resulting from a rise or fall in base-level

    SciTech Connect

    Wood, L.J.; Ethridge, F.G.; Schumm, S.A. )

    1991-03-01

    Extensive research in the past decade concerning the effects of base-level fluctuations on coastal plain-shelf-slope systems along passive margins has failed to properly assess the influence of the subaqueous shelf angle on the development, character, and preservation of the resulting deposits. A series of experiments were performed in a 4 m by 7 m flume to examine the effect that differing shelf angles have on a simulated coastal plain-shelf-slope system undergoing a cycle of base-level rise and fall. Results of the experiments indicate that the angle of the shelf affects (1) the amount of sediment available for deposition, (2) the timing of the influx of drainage basin sediment into the lower portions of the fluvial system, and (3) the width to depth ratio and sinuosity of fluvial systems that develop on the shelf. Base-level fall over a steep shelf results in deep, narrow, straight fluvial channels on the shelf and fine-grained, thick shelf-margin deltas. Depositional systems show high sedimentation rates, but a low ratio of coarse-grained to fine-grained sediment. Multiple fluvial incisions on the shelf are rapidly abandoned for a single incised valley. In contrast, gentle shelf angles result in shallow, wide, meandering fluvial channels on the shelf and coarser-grained, thinner shelf-margin deltas. Depositional systems have a lower sedimentation rate, but a high ratio of coarse-grained to fine-grained sediment. Multiple fluvial incisions on the shelf are active for a longer period of time. During subsequent base-level rise, deposits have a low potential for preservation owing to their thin nature and the slower rate at which transgression occurs over the shelf.

  12. Detachment of deposited colloids by advancing and receding air-water interfaces.

    PubMed

    Aramrak, Surachet; Flury, Markus; Harsh, James B

    2011-08-16

    Moving air-water interfaces can detach colloidal particles from stationary surfaces. The objective of this study was to quantify the effects of advancing and receding air-water interfaces on colloid detachment as a function of interface velocity. We deposited fluorescent, negatively charged, carboxylate-modified polystyrene colloids (diameter of 1 μm) into a cylindrical glass channel. The colloids were hydrophilic with an advancing air-water contact angle of 60° and a receding contact angle of 40°. After colloid deposition, two air bubbles were sequentially introduced into the glass channel and passed through the channel at different velocities (0.5, 7.7, 72, 982, and 10,800 cm/h). The passage of the bubbles represented a sequence of receding and advancing air-water interfaces. Colloids remaining in the glass channel after each interface passage were visualized with confocal microscopy and quantified by image analysis. The advancing air-water interface was significantly more effective in detaching colloids from the glass surface than the receding interface. Most of the colloids were detached during the first passage of the advancing air-water interface, while the subsequent interface passages did not remove significant amounts of colloids. Forces acting on the colloids calculated from theory corroborate our experimental results, and confirm that the detachment forces (surface tension forces) during the advancing air-water interface movement were stronger than during the receding movement. Theory indicates that, for hydrophilic colloids, the advancing interface movement generally exerts a stronger detachment force than the receding, except when the hysteresis of the colloid-air-water contact angle is small and that of the channel-air-water contact angle is large.

  13. 5 CFR 842.811 - Deposits for second-level supervisory air traffic controller service performed before February 10...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 5 Administrative Personnel 2 2012-01-01 2012-01-01 false Deposits for second-level supervisory air traffic controller service performed before February 10, 2004. 842.811 Section 842.811 Administrative... Regulations Pertaining to Noncodified Statutes § 842.811 Deposits for second-level supervisory air...

  14. 5 CFR 842.811 - Deposits for second-level supervisory air traffic controller service performed before February 10...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 5 Administrative Personnel 2 2014-01-01 2014-01-01 false Deposits for second-level supervisory air traffic controller service performed before February 10, 2004. 842.811 Section 842.811 Administrative... Regulations Pertaining to Noncodified Statutes § 842.811 Deposits for second-level supervisory air...

  15. 5 CFR 842.811 - Deposits for second-level supervisory air traffic controller service performed before February 10...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 2 2013-01-01 2013-01-01 false Deposits for second-level supervisory air traffic controller service performed before February 10, 2004. 842.811 Section 842.811 Administrative... Regulations Pertaining to Noncodified Statutes § 842.811 Deposits for second-level supervisory air...

  16. Dry deposition and soil-air gas exchange of polychlorinated biphenyls (PCBs) in an industrial area.

    PubMed

    Bozlaker, Ayse; Odabasi, Mustafa; Muezzinoglu, Aysen

    2008-12-01

    Ambient air and dry deposition, and soil samples were collected at the Aliaga industrial site in Izmir, Turkey. Atmospheric total (particle+gas) Sigma(41)-PCB concentrations were higher in summer (3370+/-1617 pg m(-3), average+SD) than in winter (1164+/-618 pg m(-3)), probably due to increased volatilization with temperature. Average particulate Sigma(41)-PCBs dry deposition fluxes were 349+/-183 and 469+/-328 ng m(-2) day(-1) in summer and winter, respectively. Overall average particulate deposition velocity was 5.5+/-3.5 cm s(-1). The spatial distribution of Sigma(41)-PCB soil concentrations (n=48) showed that the iron-steel plants, ship dismantling facilities, refinery and petrochemicals complex are the major sources in the area. Calculated air-soil exchange fluxes indicated that the contaminated soil is a secondary source to the atmosphere for lighter PCBs and as a sink for heavier ones. Comparable magnitude of gas exchange and dry particle deposition fluxes indicated that both mechanisms are equally important for PCB movement between air and soil in Aliaga.

  17. Rise and fall of bat population induced from immobile elements and fossil helminth eggs of bat guano deposits, Korea

    NASA Astrophysics Data System (ADS)

    Jun, Chang-Pyo; Lee, Seong-Joo

    2014-05-01

    Bat guano samples were collected from three carbonate caves located along the eastern coast of Korean Peninsula: Gossi Cave (40 cm high and 200 cm wide dome), Baegryong Cave (50 cm high and 100 cm wide dome), and Seongryu Cave (20 cm high platform). The guano deposits are rich in organic materials including undigested insect fragments, together with authigenic minerals and imported clastic sediments. The guano profiles were calculated to have been deposited 1) from 3097 to 4200 BP yrs in Gossi guano, 2) from 3650 to 7150 BP yrs in Baegryong guano, and 3) from 150 to 6000 BP yrs in Seongryu guano. Among the immobile elements identified, three immobile elements including Al2O3, SiO2, and TiO2 were detected from all the bat guano profiles. Distributional pattern of these elements throughout each guano profile also shows a close similarity. Such immobile elements are those of clastic sediments blown into the caves as dust. The amount of such immobile elements is closely related with deposition rate of the bat guano; low concentration of those elements implies rapid deposition rate while high concentration represents slow deposition rate of bat guano profiles. Basically, deposition rate of bat guano is controlled by the population density of bat lived in the cave. The amount of immobile elements of the Gossi Cave, for example, tends to increase toward top layer with a sudden decrease at the middle-upper layer (4,000 BP yr). It is, thus be concluded that bat population experienced fluctuation showing an decrease from 6150 to 4150 BP yr and sudden increase at 4000 BP yr, followed by constant decrease to 3150 BP yr. Fossil parasite eggs were also found from the guano deposits, and the number of parasite eggs show similar trend to that of immobile elements.

  18. The fabrication of a micro-spiral structure using EDM deposition in the air

    NASA Astrophysics Data System (ADS)

    Chi, Guanxin; Wang, Zhenlong; Xiao, K.; Cui, Jingzhi; Jin, Baidong

    2008-03-01

    A novel micromachining method to deposit a micro-3D spiral structure in air using electrical discharge machining (EDM) with a brass electrode was presented. During the deposition process, a 3D spiral structure is obtained only by the feed of the z-axis in the vertical direction. Furthermore, the obtained structure can be formed and repeated stably even in the upside-down direction under a gravity environment. It is seen that the material components of a micro-spiral structure are almost the same as those of an electrode by the energy spectrum analysis of a micro-spiral structure. According to scanning electron microscope photographs, the micro-spiral appears to feature a layered material organism structure and has compact bonding with the body material. In order to understand the forming mechanism of this kind of micro-spiral structure, simulation analysis is conducted. The track of the deposition particles can be obtained by simulation, which determines the shape of the deposited structure. According to the simulation results, the track of the deposition particles is consistent with that of EDM experiments. It is further found that the distribution of the electromagnetic field in a discharge channel has an important influence on the deposited structure and the track of the deposition particles.

  19. Air pollutant deposition at declining forest sites of the Tanzawa Mountains, Japan

    NASA Astrophysics Data System (ADS)

    Igawa, Manabu; Kojima, Kyosuke; Yoshimoto, Osamu; Nanzai, Ben

    2015-01-01

    Fir and beech trees have been dying in the Tanzawa Mountains, which are located southwest of the Kanto Plain. We have observed fog characteristics since 1988 in Mt. Oyama, which is isolated from others, located southeast of the Mountains. Acid fog has been frequently observed there. The annual mean pH of the fog has remained roughly constant, but the pH distribution of fog has shifted to higher pH recently, which corresponds closely with the improvement of air pollution at the base of Mt. Oyama. Acid fog is still formed, and it may have affected tree species such as fir and beech, which are sensitive to air pollution. We observed rainy periods and foggy periods using a visibility meter at the mountain top. The canopies at the high altitude are confirmed to be wetted for a long period, which might enhance the air pollutant deposition. We also observed air pollution and wet deposition at Mt. Nabewari, located southwest of the Tanzawa Mountains. The acid gas concentrations are about the same level in the two mountains and are in the order of SO2 > HNO3 > HCl. Comparison of wet deposition at the summit of Mt. Nabewari to that of Mt. Oyama also revealed that they were of similar levels. In the Tanzawa Mountains, fir trees and beech trees are declining by the damage of acid fog, although the high concentration ozone and the other factors may have also affected them.

  20. Contribution of ship emissions to the concentration and deposition of air pollutants in Europe

    NASA Astrophysics Data System (ADS)

    Aksoyoglu, S.; Prévôt, A. S. H.; Baltensperger, U.

    2015-11-01

    Emissions from the marine transport sector are one of the least regulated anthropogenic emission sources and contribute significantly to air pollution. Although strict limits were introduced recently for the maximum sulfur content in marine fuels in the SECAs (sulfur emission control areas) and in the EU ports, sulfur emissions outside the SECAs and emissions of other components in all European maritime areas have continued to increase in the last two decades. We have used the air quality model CAMx with and without ship emissions for the year 2006 to determine the effects of international shipping on the annual as well as seasonal concentrations of ozone, primary and secondary components of PM2.5 and the dry and wet deposition of nitrogen and sulfur compounds in Europe. Our results suggest that emissions from international shipping affect the air quality in northern and southern Europe differently and their contributions to the air concentrations vary seasonally. The largest changes in pollutant concentrations due to ship emissions were predicted for summer. Increased concentrations of the primary particle mass were found only along the shipping routes whereas concentrations of the secondary pollutants were affected over a larger area. Concentrations of particulate sulfate increased due to ship emissions in the Mediterranean (up to 60 %), in the English Channel and the North Sea (30-35 %) while increases in particulate nitrate levels were found especially in the north, around the Benelux area (20 %) where there were high NH3 land-based emissions. Our model results showed that not only the atmospheric concentrations of pollutants are affected by ship emissions, but also depositions of nitrogen and sulfur compounds increase significantly along the shipping routes. NOx emissions from the ships especially in the English Channel and the North Sea, cause a decrease in the dry deposition of reduced nitrogen at source regions by moving it from the gas-phase to the

  1. The sky is falling: chemical characterization and corrosion evaluation of deposition produced during the static testing of solid rocket motors.

    PubMed

    Doucette, William J; McNeill, Laurie S; Mendenhall, Scout; Hancock, Paul V; Wells, Jason E; Thackeray, Kevin J; Gosen, David P

    2013-03-01

    Static tests of horizontally restrained rocket motors at the ATK facility in Promontory UT, USA result in the deposition of entrained soil and fuel combustion products, referred to as Test Fire Soil (TFS), over areas as large as 30-50 mile (80-130 km) and at distances up to 10-12 miles (16-20 km) from the test site. Chloride is the main combustion product generated from the ammonium perchlorate-aluminum based composite propellant. Deposition sampling/characterization and a 6-month field corrosivity study using mild steel coupons were conducted in conjunction with the February 25th 2010 FSM-17 static test. The TFS deposition rates at the three study sites ranged from 1 to 5 g/min/m. TFS contained significantly more chloride than the surface soil collected from the test site. The TFS collected during two subsequent tests had similarly elevated chloride, suggesting that the results obtained in this study are applicable to other tests assuming that the rocket fuel composition remains similar. The field-deployed coupons exposed to the TFS had higher corrosion rates (3.6-5.0 mpy) than paired non-exposed coupons (1.6-1.8 mpy). Corrosion rates for all coupons decreased over time, but coupons exposed to the TFS always had a higher rate than the non-exposed. Differences in corrosion rates between the three study sites were also observed, with sites receiving more TFS deposition having higher corrosion rates.

  2. Depositional environments, sequence stratigraphy, and trapping mechanisms of Fall River Formation in Donkey Creek and Coyote Creek oil fields, Powder River basin, Wyoming

    SciTech Connect

    Knox, P.R. )

    1989-09-01

    Donkey Creek and Coyote Creek fields contain combined reserves of approximately 35 million bbl of oil and are within a trend of fields on the eastern flank of the Powder River basin that totals over 100 million bbl of reserves. The principal producing formation is the Lower Cretaceous Fall River Sandstone. A study of 45 cores and 248 logs from the three pools in the Donkey Creek and Coyote fields has shown that the Fall River is composed of three progradational deltaic units deposited during a period of rising relative sea level. These are locally eroded and are filled by a fluvial point-bar complex deposited following a lowering of relative sea level. Four important depositional facies have been recognized: the delta-front and distributary-channel sandstone of the highstand deltaic sequence and the point-bar sandstone and channel-abandonment of the lowstand fluvial sequence. Stratigraphic traps in Coyote Creek and south Donkey Creek pools are the result of permeable (250 md) point-bar sandstone (250 bbl oil/day ip) bounded updip by impermeable (0.1 md) channel abandonment mudstone. Most of the oil in the central Donkey Creek pool is produced from permeable (76 md) distributary-channel sandstone (150 bbl oil/day ip), which is restricted to the western flank of a structural nose. Lesser production, on the crest and upper western flank of the structure, is obtained from the less permeable (2.8 md) delta-front sandstone (50 bbl oil/day ip). Production is possibly limited to the crest and western flank by hydrodynamic processes.

  3. Contribution of ship emissions to the concentration and deposition of air pollutants in Europe

    NASA Astrophysics Data System (ADS)

    Aksoyoglu, Sebnem; Baltensperger, Urs; Prévôt, André S. H.

    2016-02-01

    Emissions from the marine transport sector are one of the least-regulated anthropogenic emission sources and contribute significantly to air pollution. Although strict limits were introduced recently for the maximum sulfur content in marine fuels in the SECAs (sulfur emission control areas) and in EU ports, sulfur emissions outside the SECAs and emissions of other components in all European maritime areas have continued to increase in the last two decades. We have used the air quality model CAMx (Comprehensive Air Quality Model with Extensions) with and without ship emissions for the year 2006 to determine the effects of international shipping on the annual as well as seasonal concentrations of ozone, primary and secondary components of PM2.5, and the dry and wet deposition of nitrogen and sulfur compounds in Europe. The largest changes in pollutant concentrations due to ship emissions were predicted for summer. Concentrations of particulate sulfate increased due to ship emissions in the Mediterranean (up to 60 %), the English Channel and the North Sea (30-35 %), while increases in particulate nitrate levels were found especially in the north, around the Benelux area (20 %), where there were high NH3 land-based emissions. Our model results showed that not only are the atmospheric concentrations of pollutants affected by ship emissions, but also depositions of nitrogen and sulfur compounds increase significantly along the shipping routes. NOx emissions from the ships, especially in the English Channel and the North Sea, cause a decrease in the dry deposition of reduced nitrogen at source regions by moving it from the gas phase to the particle phase which then contributes to an increase in the wet deposition at coastal areas with higher precipitation. In the western Mediterranean region, on the other hand, model results show an increase in the deposition of oxidized nitrogen (mostly HNO3) due to the ship traffic. Dry deposition of SO2 seems to be significant along

  4. The Cão Grande phonolitic fall deposit on Santo Antão, Cape Verde Islands

    NASA Astrophysics Data System (ADS)

    Mortensen, A. K.; Wilson, J. R.; Holm, P. M.

    2009-01-01

    The ˜ 0.2 Ma old Cão Grande subplinian to plinian fallout deposit forms a prominent and widespread, white marker horizon on the island of Santo Antão, Cape Verde Islands. The Cão Grande deposit is emplaced within the younger volcanic sequences of the island. There were two fallout events giving rise to widespread CGI and minor CGII deposits. We focus exclusively on CGI. Isopleth and isopach maps for CGI, based on data collected from 60 profiles, indicate that the volcanic vent was located in the westernmost part of the island in the area now occupied by the 1979 m-high Tope de Coroa volcano. We estimate that a minimum of 1.7-2.7 km 3 of phonolitic magma was extracted during the CGI eruption. A 30-34 km high, sustained, subplinian to plinian eruption column rose over the vent and wind subsequently dispersed the pyroclasts dominantly eastwards so thick deposits accumulated across Santo Antão. From the bottom the CGI pumice is divided into units A, B, C and D based on the geochemical evolution with stratigraphic height. Whole rock chemical compositions become overall more primitive upwards through an 8.5 m-thick profile, consistent with tapping of phonolitic melt downwards from the top of a compositionally zoned magma chamber. It is proposed that the chamber was tapped from a location on the flank of its dome-shaped roof. Lateral withdrawal of progressively deeper magma (to form Unit A) was followed by the tapping of mixed magma involving the extremely evolved melt under the roof (Unit B). Compositional breaks in the profile at 4.5 m are believed to reflect a density-step in the zoned magma column. Continued withdrawal from progressively deeper levels (Unit C) gave rise to increasingly primitive-upwards phonolitic pumice in the next 2 m of the deposit. The uppermost 2 m (Unit D) contains increasingly abundant lithic fragments as a result of the gradual collapse of the volcanic conduit. The Tope de Coroa volcano is located within a horseshoe-shaped depression in

  5. Pre-eruptive storage conditions of the Huckleberry Ridge Tuff from quartz-hosted melt inclusions in the initial fall deposits

    NASA Astrophysics Data System (ADS)

    Myers, M.; Wallace, P. J.; Wilson, C. J.

    2013-12-01

    The Yellowstone Plateau volcanic field is one of the Earth's largest young silicic volcanic systems, erupting over 6,000 cubic kilometers of rhyolite in the Quaternary. The two most voluminous eruptions, the Huckleberry Ridge Tuff (HRT) (2.06 Ma, ~2500 km3) and the Lava Creek Tuff (0.62 Ma, ~1000 km3) are amongst the largest Quaternary eruptions on Earth. Geochemical studies of these deposits can reveal information on the accumulation and storage of silicic magma in this voluminous system and may also be useful for comparisons for current monitoring efforts. We have analyzed volatiles (H2O, CO2, F, Cl) and major elements in quartz-hosted melt inclusions (MIs) from near the top of the HRT fall deposit (the most coarse-grained part), which was deposited before eruption of the three major HRT ignimbrite units. We have combined these data with cathodoluminescence (CL) imaging on the host quartz crystals to obtain information on the evolution of the magmatic system before such a voluminous eruption. The major element compositions of the MIs indicate an evolved and homogeneous melt composition, with SiO2 ranging from 75.0-77.0 wt.% on an anhydrous basis. The MIs fall into two different populations based on color. Clear MIs have H2O concentrations of 0.5-1.5 wt.%, with CO2 >400 ppm, whereas brown MIs have H2O values falling mostly between 2.0-3.5 wt.%, with lower CO2 (100-300 ppm). These two MI populations, however, do not appear to show any other compositional distinction, with similar Cl (1100-1700 ppm) and F (1500-5500 ppm) ranges, as well as indistinguishable major element compositions. Both populations give similar vapor saturation pressure ranges (1000-1300 bars), implying pre-eruptive storage at similar depths. CL imaging distinguishes at least three populations of quartz crystals that also appear to be independent of MI composition. These populations include: (a) crystals with fine-scale oscillatory zoning, (b) crystals with broader zones separated by diffuse

  6. Estimates of the atmospheric deposition of sulfur and nitrogen species: Clean Air Status and Trends Network 1990-2000.

    PubMed

    Baumgardner, Ralph E; Lavery, Thomas F; Rogers, Christopher M; Isil, Selma S

    2002-06-15

    The Clean Air Status and Trends Network (CASTNet) was established by the U.S. EPA in response to the requirements of the 1990 Clean Air Act Amendments. To satisfy these requirements CASTNet was designed to assess and report on geographic patterns and long-term, temporal trends in ambient air pollution and acid deposition in order to gauge the effectiveness of current and future mandated emission reductions. This paper presents an analysis of the spatial patterns of deposition of sulfur and nitrogen pollutants for the period 1990-2000. Estimates of deposition are provided for two 4-yr periods: 1990-1993 and 1997-2000. These two periods were selected to contrast deposition before and after the large decrease in SO2 emissions that occurred in 1995. Estimates of dry deposition were obtained from measurements at CASTNet sites combined with deposition velocities that were modeled using the multilayer model, a 20-layer model that simulates the various atmospheric processes that contribute to dry deposition. Estimates of wet deposition were obtained from measurements at sites operated bythe National Atmospheric Deposition Program. The estimates of dry and wet deposition were combined to calculate total deposition of atmospheric sulfur (dry SO2, dry and wet SO4(2-)) and nitrogen (dry HNO3, dry and wet NO3-, dry and wet NH4+). An analysis of the deposition estimates showed a significant decline in sulfur deposition and no change in nitrogen deposition. The highest rates of sulfur deposition were observed in the Ohio River Valley and downwind states. This region also observed the largest decline in sulfur deposition. The highest rates of nitrogen deposition were observed in the Midwest from Illinois to southern New York State. Sulfur and nitrogen deposition fluxes were significantly higher in the eastern United States as compared to the western sites. Dry deposition contributed approximately 38% of total sulfur deposition and 30% of total nitrogen deposition in the eastern

  7. Monitoring ambient air pollutants and apply Woods' model in the prediction seasonal dry deposition at Chang-Hua (urban) and Kao-Mei (wetland) county, Taiwan.

    PubMed

    Fang, Guor-Cheng; Chang, Chia-Ying

    2014-09-01

    The main purpose for this study was to monitor ambient air particles and metallic elements (Mn, Fe, Zn, Cr, Cu and Pb) in total suspended particulate (TSP) concentration and dry deposition. In addition, the calculated/measured dry deposition flux ratios of ambient air particles and metallic elements (Mn, Fe, Zn, Cr, Cu and Pb) were evaluated using Woods' model at urban and wetland areas for the 2009-2010 period. The results indicated that the mean highest concentrations of metallic elements Mn, Fe, Zn, Cr, Cu and Pb in TSP were found in Chang-Hua (urban) sampling site. And as for the two characteristic sampling sites, the Woods' model exhibits better dry deposition of particulates of 18 µm particle size than the rest of the other particle sizes at any sampling site in this study. The average calculated/measured flux ratios for two seasons (summer and fall) by using Woods model at 2.5, 10 and 18 µm particles sizes were also studied. The results indicated that the average calculated/measured flux ratios orders for two seasons of various particles sizes were all displayed as Fe > Mn > Zn > Cu > Cr > Pb > particle. And these calculated/measured flux ratios orders were Fe > Mn > Cu > Zn > Cr > Pb > particle and were Fe > Mn > Zn > Cu > Cr > particle > Pb, during spring and winter seasons, respectively. Finally, in the spring and summer seasons of Gao-Mei (wetland) sampling site, the average calculated/measured flux ratios using Woods' model was found to be 2.5, 10 and 18 µm, showing the order of the calculated/measured flux ratios to be Fe > Cu > Zn > Mn > Cr > Pb > particle. And the calculated/measured flux ratio orders were Fe > Zn > Mn > Cu > Cr > particle > Pb and were Fe > Cu > Zn > Mn > Cr > particle > Pb for fall and winter season, respectively.

  8. Trends in mercury wet deposition and mercury air concentrations across the U.S. and Canada.

    PubMed

    Weiss-Penzias, Peter S; Gay, David A; Brigham, Mark E; Parsons, Matthew T; Gustin, Mae S; Ter Schure, Arnout

    2016-10-15

    This study examined the spatial and temporal trends of mercury (Hg) in wet deposition and air concentrations in the United States (U.S.) and Canada between 1997 and 2013. Data were obtained from the National Atmospheric Deposition Program (NADP) and Environment Canada monitoring networks, and other sources. Of the 19 sites with data records from 1997-2013, 53% had significant negative trends in Hg concentration in wet deposition, while no sites had significant positive trends, which is in general agreement with earlier studies that considered NADP data up until about 2010. However, for the time period 2007-2013 (71 sites), 17% and 13% of the sites had significant positive and negative trends, respectively, and for the time period 2008-2013 (81 sites) 30% and 6% of the sites had significant positive and negative trends, respectively. Non-significant positive tendencies were also widespread. Regional trend analyses revealed significant positive trends in Hg concentration in the Rocky Mountains, Plains, and Upper Midwest regions for the recent time periods in addition to significant positive trends in Hg deposition for the continent as a whole. Sulfate concentration trends in wet deposition were negative in all regions, suggesting a lower importance of local Hg sources. The trend in gaseous elemental Hg from short-term datasets merged as one continuous record was broadly consistent with trends in Hg concentration in wet deposition, with the early time period (1998-2007) producing a significantly negative trend (-1.5±0.2%year(-1)) and the recent time period (2008-2013) displaying a flat slope (-0.3±0.1%year(-1), not significant). The observed shift to more positive or less negative trends in Hg wet deposition primarily seen in the Central-Western regions is consistent with the effects of rising Hg emissions from regions outside the U.S. and Canada and the influence of long-range transport in the free troposphere. PMID:26803218

  9. 5 CFR 842.811 - Deposits for second-level supervisory air traffic controller service performed before February 10...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES RETIREMENT SYSTEM-BASIC ANNUITY Law Enforcement Officers, Firefighters, and Air Traffic Controllers... to OPM immediately for deposit to the Civil Service Retirement and Disability Fund. (5) Once...

  10. 5 CFR 842.811 - Deposits for second-level supervisory air traffic controller service performed before February 10...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES RETIREMENT SYSTEM-BASIC ANNUITY Law Enforcement Officers, Firefighters, and Air Traffic Controllers... to OPM immediately for deposit to the Civil Service Retirement and Disability Fund. (5) Once...

  11. A multi-resolution assessment of the Community Multiscale Air Quality (CMAQ) Model v4.7 wet deposition estimates for 2002-2006

    NASA Astrophysics Data System (ADS)

    Appel, K. W.; Foley, K. M.; Bash, J. O.; Pinder, R. W.; Dennis, R. L.; Allen, D. J.; Pickering, K.

    2010-12-01

    This paper examines the operational performance of the Community Multiscale Air Quality (CMAQ) model simulations for 2002-2006 using both 36-km and 12-km horizontal grid spacing with a primary focus on the performance of the CMAQ model in predicting wet deposition of sulfate (SO4=), ammonium (NH4+) and nitrate (NO3-). Performance of the wet deposition species is determined by comparing CMAQ predicted concentrations to concentrations measured by the National Acid Deposition Program (NADP), specifically the National Trends Network (NTN). For SO4= wet deposition, the CMAQ model estimates were generally comparable between the 36-km and 12-km simulations for the eastern US, with the 12-km simulation giving slightly higher estimates of SO4= wet deposition than the 36-km simulation on average. The normalized mean bias (NMB) was slightly higher for the 12-km simulation, however, both simulations had annual biases that were less than ±15% for each of the five years. The model estimated SO4= wet deposition values improved when they were adjusted to account for biases in the model estimated precipitation. The CMAQ model underestimates NH4+ wet deposition over the eastern US using both the 36-km and 12-km horizontal grid spacing, with a slightly larger underestimation in the 36-km simulation. The largest underestimations occur during the winter and spring periods, while the summer and fall have slightly smaller underestimations of NH4+ wet deposition. Annually, the NMB generally ranges between -10% and -16% for the 12-km simulation and -12% to -18% for the 36-km simulation over the five-year period for the eastern US. The underestimation in NH4+ wet deposition is likely due, in part, to the poor temporal and spatial representation of ammonia (NH3) emissions, particularly those emissions associated with fertilizer applications and NH3 bi-directional exchange. The model performance for estimates of NO3- wet deposition are mixed throughout the year, with the model largely

  12. Tephra-fall deposits from the 1992 eruption of Crater Peak, Alaska: implications of clast textures for eruptive processes

    USGS Publications Warehouse

    Gardner, C.A.; Cashman, K.V.; Neal, C.A.

    1998-01-01

    The 1992 eruption of Crater Peak, Mount Spurr, Alaska, involved three subplinian tephra-producing events of similar volume and duration. The tephra consists of two dense juvenile clast types that are identified by color, one tan and one gray, of similar chemistry, mineral assemblage, and glass composition. In two of the eruptive events, the clast types are strongly stratified with tan clasts dominating the basal two thirds of the deposits and gray clasts the upper one third. Tan clasts have average densities between 1.5 and 1.7 g/cc and vesicularities (phenocryst free) of approximately 42%. Gray clasts have average densities between 2.1 and 2.3 g/cc, and vesicularities of approximately 20%; both contain abundant microlites. Average maximum plagioclase microlite lengths (13-15 ??m) in gray clasts in the upper layer are similar regardless of eruptive event (and therefore the repose time between them) and are larger than average maximum plagioclase microlite lengths (9-11 ???m) in the tan clasts in the lower layer. This suggests that microlite growth is a response to eruptive processes and not to magma reservoir heterogeneity or dynamics. Furthermore, we suggest that the low vesicularities of the clasts are due to syneruptive magmatic degassing resulting in microlitic growth prior to fragmentation and not to quenching of clasts by external groundwater.

  13. A multi-resolution assessment of the Community Multiscale Air Quality (CMAQ) model v4.7 wet deposition estimates for 2002-2006

    NASA Astrophysics Data System (ADS)

    Appel, K. W.; Foley, K. M.; Bash, J. O.; Pinder, R. W.; Dennis, R. L.; Allen, D. J.; Pickering, K.

    2011-05-01

    This paper examines the operational performance of the Community Multiscale Air Quality (CMAQ) model simulations for 2002-2006 using both 36-km and 12-km horizontal grid spacing, with a primary focus on the performance of the CMAQ model in predicting wet deposition of sulfate (SO4=), ammonium (NH4+) and nitrate (NO3-). Performance of the wet deposition estimates from the model is determined by comparing CMAQ predicted concentrations to concentrations measured by the National Acid Deposition Program (NADP), specifically the National Trends Network (NTN). For SO4= wet deposition, the CMAQ model estimates were generally comparable between the 36-km and 12-km simulations for the eastern US, with the 12-km simulation giving slightly higher estimates of SO4= wet deposition than the 36-km simulation on average. The result is a slightly larger normalized mean bias (NMB) for the 12-km simulation; however both simulations had annual biases that were less than ±15 % for each of the five years. The model estimated SO4= wet deposition values improved when they were adjusted to account for biases in the model estimated precipitation. The CMAQ model underestimates NH4+ wet deposition over the eastern US, with a slightly larger underestimation in the 36-km simulation. The largest underestimations occur in the winter and spring periods, while the summer and fall have slightly smaller underestimations of NH4+ wet deposition. The underestimation in NH4+ wet deposition is likely due in part to the poor temporal and spatial representation of ammonia (NH3) emissions, particularly those emissions associated with fertilizer applications and NH3 bi-directional exchange. The model performance for estimates of NO3- wet deposition are mixed throughout the year, with the model largely underestimating NO3- wet deposition in the spring and summer in the eastern US, while the model has a relatively small bias in the fall and winter. Model estimates of NO3- wet deposition tend to be slightly

  14. Transformation of a Water Slug in Free Fall Under the Conditions of Exposure to an Air Flow Orthogonal to the Direction of the Slug Motion

    NASA Astrophysics Data System (ADS)

    Volkov, R. S.; Zabelin, M. V.; Kuznetsov, G. V.; Strizhak, P. A.

    2016-07-01

    An experimental study has been made of the influence of an orthogonal (side) air flow propagating with a velocity to 5 m/s on the phases of transformation of a water slug with an initial volume of 0.05-0.5 liter in free fall from a height of 3 m. Use was made of Phantom V411 and Phantom Miro M310 high-speed video cameras and a Tema Automotive software system with the function of continuous tracking. The laws of retardation of the phases of transformation of the water slug from the instant of formation to that of formation of a droplet cloud under the action of the air flow orthogonal to the direction of the slug motion, and also of the deceleration, removal, and destruction of the droplets and fragments of water separating from the slug surface, have been established.

  15. Stratigraphy, depositional history, and trapping mechanisms of Lone Tree Creek and Lodgepole Creek oil fields, Lower Cretaceous Fall River formation, Powder River Basin, Wyoming

    SciTech Connect

    Gustason, E.R.; Ryer, T.A.

    1985-05-01

    Stratigraphically trapped accumulations of oil in the Lone Tree Creek and Lodgepole Creek fields occur within and just updip from a fluvial meander belt within the Fall River Formation. The meander belt can be mapped north-to-south over a distance of at least 100 mi (161 km) in the eastern part of the Powder River basin. The northern part of the meander belt contains the oil fields of the Coyote Creek-Miller Creek trend; the southern part contains only the relatively small Lone Tree Creek and Lodgepole Creek fields. These small fields are of considerable interest, as they display a style of stratigraphic trapping of hydrocarbons not observed in the prolific Coyote Creek-Miller Creek trend. The stratigraphic traps of the Coyote Creek-Miller Creek trend occur at updip facing convexities along the eastern edge of the meander belt, with abandonment clay plugs serving as lateral permeability barriers to hydrocarbon migration. Oil has been produced in part of the Lone Tree Creek field from a similar trap. The remaining part of Lone Tree Creek field and Lodgepole creek field produce from stratigraphic traps formed by lateral pinch-outs of delta-front sandstone bodies. These traps are situated updip from and apparently in continuity with the meander-belt deposits, indicating that they may have been charged with hydrocarbons that found their way through the clay-plug barriers along the margin of the meander belt. Similar, undiscovered traps may exist updip from Fall River meander belts elsewhere in the basin.

  16. Hydrostatic pressure effect on micro air bubbles deposited on surfaces with a retreating tip.

    PubMed

    Huynh, So Hung; Wang, Jingming; Yu, Yang; Ng, Tuck Wah

    2014-06-01

    The effect of hydrostatic pressure on 6 μL air bubbles formed on micropillar structured PDMS and silicone surfaces using a 2 mm diameter stainless steel tip retreated at 1 mm/s was investigated. Dimensional analysis of the tip retraction process showed the experiments to be conducted in the condition where fluid inertial forces are comparable in magnitude with surface tension forces, while viscous forces were lower. Larger bubbles could be left behind on the structured PDMS surface. For hydrostatic pressures in excess of 20 mm H2O (196 Pa), the volume of bubble deposited was found to decrease progressively with pressure increase. The differences in width of the deposited bubbles (in contact with the substrate) were significant at any particular pressure but marginal in height. The attainable height before rupture reduced with pressure increase, thereby accounting for the reducing dispensed volume characteristic. On structured PDMS, the gaseous bridge width (in contact with the substrate) was invariant with tip retraction, while on silicone it was initially reducing before becoming invariant in the lead up to rupture. With silicone, hence, reductions in the contact width and height were both responsible for reduced volumes with pressure increase. Increased hydrostatic pressure was also found to restrict the growth in contact width on silicone during the stage when air was injected in through the tip. The ability to effect bubble size in such a simple manner may already be harnessed in nature and suggests possibilities in technological applications.

  17. Impact of subjacent rocks at the water and air regime of the depleted peat deposits

    NASA Astrophysics Data System (ADS)

    Rakovich, V. A.

    2009-04-01

    At the depleted peat deposits (after peat extraction), where the residual layer of peat with the thickness of about 0,5 meters is laid at the well water permeable rocks, vegetation typical for dry conditions is developed in case of good drainage conditions; birch trees, willow, alder-trees and buckthorn prevail in this vegetation. Water and air regime is characterized here by good aeration with prevailing of oxidative processes. If water regime is regulated, these depleted peat areas are suitable for agricultural and forest lands; however, necessity of transformation of these depleted lands into forest and agricultural lands must be ecologically and economically justified. If the residual layer of peat with the thickness of 0,05-0,3 m is based at the sapropel or peat sapropel, contrast amphibiotic water and air regime with strong fluctuation of oxidative and restoration process depending on the weather conditions is formed; this regime is formed without artificial increase of the ground waters level. This does not allow bog vegetation or vegetation typical for dry conditions to develop. Thus, within 20 and more years after completion of peat extraction, such areas are not covered by vegetation in spite of favorable agro-chemical qualities of peat layer and favorable for vegetation chemical composition of soil and ground waters. Depleted peat deposits, that are based at the sapropel, are not suitable for agricultural use, because agricultural vegetation requires stable water and air regime with good aeration and oxidative and restoration potential within 400-750 mV. Contrast amphibiotic water and air regime of the depleted peat deposits that are based at sapropel excludes possibility to use them as agricultural lands. Because of this reason, areas with residual peat layer that are based at sapropel are not suitable for forest planting. Due to periodic increase of ground waters level, rot systems of the plants can not penetrate into the required depth, and mechanical

  18. [Aerosol deposition in nasal passages of burrowing and ground rodents when breathing dust-laden air].

    PubMed

    Moshkin, M P; Petrovskiĭ, D V; Akulov, A E; Romashchenko, A V; Gerlinskaia, L A; Muchnaia, M I; Ganimedov, V L; Sadovskiĭ, A S; Savelov, A A; Koptiug, I V; Troitskiĭ, S Iu; Bukhtiiarov, V I; Kolchanov, N A; Sagdeev, R Z; Fomin, V M

    2014-01-01

    In subterranean rodents, which dig down the passages with frontal teeth, adaptation to the underground mode of life presumes forming of mechanisms that provide protection against inhaling dust particles of different size when digging. One of such mechanisms can be specific pattern of air flow organization in the nasal cavity. To test this assumption, comparative study of geometry and aerodynamics of nasal passages has been conducted with regard to typical representative of subterranean rodents, the mole vole, and a representative of ground rodents, the house mouse. Numerical modeling of air flows and deposition of micro- and nanoparticle aerosols indicates that sedimentation of model particles over the whole surface of nasal cavity is higher in mole vole than in house mouse. On the contrary, particles deposition on the surface of olfactory epithelium turns out to be substantially less in the burrowing rodent as compared to the ground one. Adaptive significance of the latter observation has been substantiated by experimental study on the uptake ofnanoparticles of hydrated manganese oxide MnO x (H2O)x and Mn ions from nasal cavity into brain. It has been shown with use of magnetic resonance tomography method that there is no difference between studied species with respect to intake of particles or ions by olfactory bulb when they are introduced intranasally. Meanwhile, when inhaling nanoparticle aerosol of MnCl2, deposition of Mn in mouse's olfactory bulbs surpasses markedly that in vole's bulbs. Thereby, the morphology of nasal passages as a factor determining the aerodynamics of upper respiratory tract ensures for burrowing rodents more efficient protection of both lungs and brain against inhaled aerosols than for ground ones. PMID:25771679

  19. Development of open air silicon deposition technology by silane-free atmospheric pressure plasma enhanced chemical transport under local ambient gas control

    NASA Astrophysics Data System (ADS)

    Naito, Teruki; Konno, Nobuaki; Yoshida, Yukihisa

    2016-07-01

    Open air silicon deposition was performed by combining silane-free atmospheric pressure plasma-enhanced chemical transport and a newly developed local ambient gas control technology. The effect of air contamination on silicon deposition was investigated using a vacuum chamber, and the allowable air contamination level was confirmed to be 3 ppm. The capability of the local ambient gas control head was investigated numerically and experimentally. A safe and clean process environment with air contamination less than 1 ppm was achieved. Combining these technologies, a microcrystalline silicon film was deposited in open air, the properties of which were comparable to those of silicon films deposited in a vacuum chamber.

  20. Modelling deposition and air concentration of reduced nitrogen in Poland and sensitivity to variability in annual meteorology.

    PubMed

    Kryza, Maciej; Dore, Anthony J; Błaś, Marek; Sobik, Mieczysław

    2011-04-01

    The relative contribution of reduced nitrogen to acid and eutrophic deposition in Europe has increased recently as a result of European policies which have been successful in reducing SO(2) and NO(x) emissions but have had smaller impacts on ammonia (NH(3)) emissions. In this paper the Fine Resolution Atmospheric Multi-pollutant Exchange (FRAME) model was used to calculate the spatial patterns of annual average ammonia and ammonium (NH(4)(+)) air concentrations and reduced nitrogen (NH(x)) dry and wet deposition with a 5 km × 5 km grid for years 2002-2005. The modelled air concentrations of NH(3) and dry deposition of NH(x) show similar spatial patterns for all years considered. The largest year to year changes were found for wet deposition, which vary considerably with precipitation amount. The FRAME modelled air concentrations and wet deposition are in reasonable agreement with available measurements (Pearson's correlation coefficients above 0.6 for years 2002-2005), and with spatial patterns of concentrations and deposition of NH(x) reported with the EMEP results, but show larger spatial gradients. The error statistics show that the FRAME model results are in better agreement with measurements if compared with EMEP estimates. The differences in deposition budgets calculated with FRAME and EMEP do not exceed 17% for wet and 6% for dry deposition, with FRAME estimates higher than for EMEP wet deposition for modelled period and lower or equal for dry deposition. The FRAME estimates of wet deposition budget are lower than the measurement-based values reported by the Chief Inspectorate of Environmental Protection of Poland, with the differences by approximately 3%. Up to 93% of dry and 53% of wet deposition of NH(x) in Poland originates from national sources. Over the western part of Poland and mountainous areas in the south, transboundary transport can contribute over 80% of total (dry + wet) NH(x) deposition. The spatial pattern of the relative contribution of

  1. One century of air deposition of hydrocarbons recorded in travertine in North Tibetan Plateau, China: Sources and evolution.

    PubMed

    Yuan, Guo-Li; Wu, Ming-Zhe; Sun, Yong; Li, Jun; Li, Jing-Chao; Wang, Gen-Hou

    2016-08-01

    The characteristic distribution patterns of hydrocarbons have been used for fingerprinting to identify their sources. The historical air depositions of hydrocarbons recorded in natural media help to understand the evolution of the air environment. Travertine is a natural acceptor of air deposition that settles on the ground layer by layer. To reconstruct the historical air environment of hydrocarbons in the North Tibetan Plateau (NTP), a unique background region, twenty-seven travertine samples were collected systematically from a travertine column according to its precipitated year. For each sample, the precipitated year was dated while n-alkanes and polycyclic aromatic hydrocarbons (PAHs) were determined. Based on source identification, the air environment of hydrocarbons in the past century was studied for the region of NTP. Before World War II, the anthropogenic sources of hydrocarbons showed little influence on the air environment. During World War II and China's War of Liberation, hydrocarbons increased significantly, mainly from the use of fossil fuels. Between 1954 and 1963, hydrocarbons in the air decreased significantly because the sources of petroleum combustion decreased. From the mid-1960s through the end of the 1990s, air hydrocarbons, which mainly originated from biomass burning, increased gradually because agriculture and animal husbandry were developing steadily in Tibet and China. From the late 1990s, hydrocarbons in the atmosphere increased rapidly due to the rapid increase of tourism activities, which might increase hydrocarbon emissions from traffic. The reconstruction of the historical air hydrocarbons in NTP clearly reflects the evolution of the region and global development.

  2. Pulsed laser deposition of air-sensitive hydride epitaxial thin films: LiH

    SciTech Connect

    Oguchi, Hiroyuki; Isobe, Shigehito; Kuwano, Hiroki; Shiraki, Susumu; Hitosugi, Taro; Orimo, Shin-ichi

    2015-09-01

    We report on the epitaxial thin film growth of an air-sensitive hydride, lithium hydride (LiH), using pulsed laser deposition (PLD). We first synthesized a dense LiH target, which is key for PLD growth of high-quality hydride films. Then, we obtained epitaxial thin films of [100]-oriented LiH on a MgO(100) substrate at 250 °C under a hydrogen pressure of 1.3 × 10{sup −2} Pa. Atomic force microscopy revealed that the film demonstrates a Stranski-Krastanov growth mode and that the film with a thickness of ∼10 nm has a good surface flatness, with root-mean-square roughness R{sub RMS} of ∼0.4 nm.

  3. Falling chains

    NASA Astrophysics Data System (ADS)

    Wong, Chun Wa; Yasui, Kosuke

    2006-06-01

    The one-dimensional fall of a folded chain with one end suspended from a rigid support and a chain falling from a resting heap on a table is studied. Because their Lagrangians contain no explicit time dependence, the falling chains are conservative systems. Their equations of motion are shown to contain a term that enforces energy conservation when masses are transferred between subchains. We show that Cayley's 1857 energy nonconserving solution for a chain falling from a resting heap is incorrect because it neglects the energy gained when a link leaves a subchain. The maximum chain tension measured by Calkin and March for the falling folded chain is given a simple if rough interpretation. Other aspects of the falling folded chain are briefly discussed.

  4. Deposition and air concentrations of permethrin and naled used for adult mosquito management.

    PubMed

    Schleier, Jerome J; Peterson, Robert K D

    2010-01-01

    One of the most effective ways of managing adult mosquitoes that vector human and animal pathogens is the use of ultra-low-volume (ULV) insecticides. Because of the lack of environmental fate studies and concerns about the safety of the insecticides used for the management of adult mosquitoes, we conducted an environmental fate study after truck-mounted applications of permethrin and naled. One hour after application, concentrations of permethrin on cotton dosimeters placed at ground level 25, 50, and 75 m from the spray source were 2, 4, and 1 ng/cm2 in 2007 and 5, 2, and 0.9 ng/cm2 in 2008, respectively. One hour after application, concentrations of naled 25, 50, and 75 m were 47, 66, and 67 ng/cm2 in 2007 and 15, 6.1, and 0 (nondetectable) ng/cm2 in 2008, respectively. Deposition concentrations 12 h after application were not significantly different than 1 h after application for permethrin and naled either year. During 2007 and 2008 permethrin applications, two quantifiable air concentrations of 375 and 397 ng/m3 were observed 1 h after application. In 2007 and 2008, naled air concentrations ranged from 2300 to 4000 ng/m3 1 h after application. There were no quantifiable air concentrations between 1 and 12 h after application in either 2007 or 2008 for both naled and permethrin. Environmental concentrations observed in this study demonstrate that models used in previous risk assessments were sufficiently conservative (i.e., the models overestimated environmental concentrations). However, we also demonstrate inadequacies of models such as AgDrift and AGDISP, which currently are used by the US Environmental Protection Agency to estimate environmental concentrations of ULV insecticides. PMID:19536586

  5. Deposition of SOCs in forests

    SciTech Connect

    Horstmann, M.; McLachlan, M.S.

    1995-12-31

    The bulk deposition, wet-only deposition, dry-only deposition and ambient air concentrations of PCDD/Fs, PCBs and PAHs were measured in an 80 year old spruce forest, an 80 year old mixed deciduous (beech and oak) forest, and in an adjacent clearing over a period of 1--2 years. The deposition of the less volatile compounds that are primarily particle bound in the atmosphere was similar at both sites. These compounds were deposited primarily through wet deposition, as shown by the measurements in the clearing. In contrast, the deposition of the more volatile compounds was much higher at the forest sites than in the clearing. For instance, the annual deposition of Cl{sub 4}DF was 5 times higher in the spruce forest and 8 times higher in the deciduous forest. The excess deposition in the deciduous forest was almost completely due to the leaf fall in October--December, while about half of the excess deposition in the spruce forest was the result of needle fall. A further, as yet unexplained deposition mechanism accounted for the remainder of the flux in the spruce forest. Other studies have shown that more volatile SOCs are deposited to vegetation primarily through dry gaseous deposition. Hence, while forests have little influence on the deposition of less volatile compounds like the higher chlorinated PCDD/Fs and the 5--6 ring PAHs, dry deposition to leaves/needles and their subsequent falling to the forest floor make forest soils an extremely important sink for more volatile SOC.

  6. MODELING ASSESSMENT OF TRANSPORT AND DEPOSITION PATTERNS OF MERCURY AIR EMISSIONS FROM THE U.S. AND CANADA

    EPA Science Inventory

    In December 1997, the U.S. EPA submitted the Mercury Study Report to Congress which included a regional-scale modeling assessment of the transport and deposition of U.S. air emissions of mercury. This modeling was performed with a modified version of the Regional Lagrangian Mode...

  7. Influence of travel speed on spray deposition uniformity from an air-assisted variable-rate sprayer

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A newly developed LiDAR-guided air-assisted variable-rate sprayer for nursery and orchard applications was tested at various travel speeds to compare its spray deposition and coverage uniformity with constant-rate applications. Spray samplers, including nylon screens and water-sensitive papers (WSP)...

  8. Insights into Pleistocene palaeoenvironments and biostratigraphy in southern Buenos Aires province (Argentina) from continental deposits

    NASA Astrophysics Data System (ADS)

    Beilinson, E.; Gasparini, G. M.; Soibelzon, L. H.; Soibelzon, E.

    2015-07-01

    The coastal cliffs of the Buenos Aires province (Argentina) have been the subject of intense paleontological studies since the XIX century. Therefore, many of the type localities in which is based the late Cenozoic Pampean biostratigraphic/chronostratigraphic scheme are located in this area. In this context, the sedimentites that crop out near the mouth of the Chocorí Creek contain a set of palaeontological sites that, because of their richness and well-preserved fossil content, hold high national and international importance. The aims of the present contribution are: 1) to make a stratigraphic and sedimentological characterization of the study area; 2) to list the fauna outcropped at these palaeontological sites and establish a biostratigraphic framework; 3) to elaborate a palaeoenvironmental model for the area. The study interval was informally subdivided into a lower, middle and upper interval. Interpretation was based on the presence of a number of key features such as architectural elements; channel:overbank ratio and palaeosol occurrence. The first two intervals were interpreted as continental deposits of a fluvio-alluvial nature and are the focus of this paper. The upper interval was related to foreshore marine deposits and will be studied in a future contribution. The lower interval is characterized mainly by overbank architectural elements in which calcisols and argillic protosols were identified. Channel-fill deposits are isolated and surrounded by fine-grained overbank successions and sedimentary structures are suggestive of mixed-load transport. The contact between the lower and middle intervals is an irregular, highly erosive surface characterized by a significant vertical change in the facies. This surface defines the base of multistorey sandbodies which's internal arrangement alongside with the low participation of overbank deposits suggests deposition by a braided fluvial system. Palaeosols and vertebrate fossils were used as palaeoclimatic

  9. Heart rate and heart rate variability assessment identifies individual differences in fear response magnitudes to earthquake, free fall, and air puff in mice.

    PubMed

    Liu, Jun; Wei, Wei; Kuang, Hui; Tsien, Joe Z; Zhao, Fang

    2014-01-01

    Fear behaviors and fear memories in rodents have been traditionally assessed by the amount of freezing upon the presentation of conditioned cues or unconditioned stimuli. However, many experiences, such as encountering earthquakes or accidental fall from tree branches, may produce long-lasting fear memories but are behaviorally difficult to measure using freezing parameters. Here, we have examined changes in heartbeat interval dynamics as physiological readout for assessing fearful reactions as mice were subjected to sudden air puff, free-fall drop inside a small elevator, and a laboratory-version earthquake. We showed that these fearful events rapidly increased heart rate (HR) with simultaneous reduction of heart rate variability (HRV). Cardiac changes can be further analyzed in details by measuring three distinct phases: namely, the rapid rising phase in HR, the maximum plateau phase during which HRV is greatly decreased, and the recovery phase during which HR gradually recovers to baseline values. We showed that durations of the maximum plateau phase and HR recovery speed were quite sensitive to habituation over repeated trials. Moreover, we have developed the fear resistance index based on specific cardiac response features. We demonstrated that the fear resistance index remained largely consistent across distinct fearful events in a given animal, thereby enabling us to compare and rank individual mouse's fear responsiveness among the group. Therefore, the fear resistance index described here can represent a useful parameter for measuring personality traits or individual differences in stress-susceptibility in both wild-type mice and post-traumatic stress disorder (PTSD) models.

  10. Heart Rate and Heart Rate Variability Assessment Identifies Individual Differences in Fear Response Magnitudes to Earthquake, Free Fall, and Air Puff in Mice

    PubMed Central

    Kuang, Hui; Tsien, Joe Z.; Zhao, Fang

    2014-01-01

    Fear behaviors and fear memories in rodents have been traditionally assessed by the amount of freezing upon the presentation of conditioned cues or unconditioned stimuli. However, many experiences, such as encountering earthquakes or accidental fall from tree branches, may produce long-lasting fear memories but are behaviorally difficult to measure using freezing parameters. Here, we have examined changes in heartbeat interval dynamics as physiological readout for assessing fearful reactions as mice were subjected to sudden air puff, free-fall drop inside a small elevator, and a laboratory-version earthquake. We showed that these fearful events rapidly increased heart rate (HR) with simultaneous reduction of heart rate variability (HRV). Cardiac changes can be further analyzed in details by measuring three distinct phases: namely, the rapid rising phase in HR, the maximum plateau phase during which HRV is greatly decreased, and the recovery phase during which HR gradually recovers to baseline values. We showed that durations of the maximum plateau phase and HR recovery speed were quite sensitive to habituation over repeated trials. Moreover, we have developed the fear resistance index based on specific cardiac response features. We demonstrated that the fear resistance index remained largely consistent across distinct fearful events in a given animal, thereby enabling us to compare and rank individual mouse’s fear responsiveness among the group. Therefore, the fear resistance index described here can represent a useful parameter for measuring personality traits or individual differences in stress-susceptibility in both wild-type mice and post-traumatic stress disorder (PTSD) models. PMID:24667366

  11. Preventing falls

    MedlinePlus

    Dalbaere K, Sherrington C, Lord SR. Falls prevention interventions. In: Marchus R, Feldman D, Depmster DW, Luckey M, Cauley JA, eds. Osteoporosis . 4th ed. Philadelphia, PA: Elsevier; 2013:chap 70. Rubenstein ...

  12. One century of air deposition of hydrocarbons recorded in travertine in North Tibetan Plateau, China: Sources and evolution.

    PubMed

    Yuan, Guo-Li; Wu, Ming-Zhe; Sun, Yong; Li, Jun; Li, Jing-Chao; Wang, Gen-Hou

    2016-08-01

    The characteristic distribution patterns of hydrocarbons have been used for fingerprinting to identify their sources. The historical air depositions of hydrocarbons recorded in natural media help to understand the evolution of the air environment. Travertine is a natural acceptor of air deposition that settles on the ground layer by layer. To reconstruct the historical air environment of hydrocarbons in the North Tibetan Plateau (NTP), a unique background region, twenty-seven travertine samples were collected systematically from a travertine column according to its precipitated year. For each sample, the precipitated year was dated while n-alkanes and polycyclic aromatic hydrocarbons (PAHs) were determined. Based on source identification, the air environment of hydrocarbons in the past century was studied for the region of NTP. Before World War II, the anthropogenic sources of hydrocarbons showed little influence on the air environment. During World War II and China's War of Liberation, hydrocarbons increased significantly, mainly from the use of fossil fuels. Between 1954 and 1963, hydrocarbons in the air decreased significantly because the sources of petroleum combustion decreased. From the mid-1960s through the end of the 1990s, air hydrocarbons, which mainly originated from biomass burning, increased gradually because agriculture and animal husbandry were developing steadily in Tibet and China. From the late 1990s, hydrocarbons in the atmosphere increased rapidly due to the rapid increase of tourism activities, which might increase hydrocarbon emissions from traffic. The reconstruction of the historical air hydrocarbons in NTP clearly reflects the evolution of the region and global development. PMID:27101457

  13. Air

    MedlinePlus

    ... do to protect yourself from dirty air . Indoor air pollution and outdoor air pollution Air can be polluted indoors and it can ... this chart to see what things cause indoor air pollution and what things cause outdoor air pollution! Indoor ...

  14. Ozone deposition to an oat crop ( Avena sativa L.) grown in open-top chambers and in the ambient air

    NASA Astrophysics Data System (ADS)

    Pleijel, H.; Wallin, G.; Karlsson, P. E.; Skarby, L.; Sellden, G.

    Fluxes and deposition velocities for ozone were determined for open-top chambers with and without an oat crop, and for the adjacent field, using a resistance analogue model and the aerodynamic wind-profile method, respectively. During a period when the canopy was green and the ambient wind speeds modest, the fluxes and deposition velocities were higher in the chamber with plants than in the field crop. The deposition to chamber walls and soil in the chamber only accounted for part of that difference. The deposition velocity for ozone to the crop was light-dependent both in the chamber with plants and in the ambient air. With increasing plant senescence, the deposition velocity declined and the light dependence disappeared. Fluctuations in deposition velocity superimposed on the overall declining trend followed the same temporal pattern in the chambers with and without plants. These fluctuations in deposition velocity may partly be explained by variations in surface wetness. Differences in boundary layer conductance between chamber and ambient, which under certain conditions may significantly influence the validity of the chamber as a test system, were observed.

  15. NOVA Fall 1999 Teacher's Guide.

    ERIC Educational Resources Information Center

    French, Wayne; Karlan, James W.; Ransick, Kristina; Rosene, Dale; Sammons, Fran Lyons; Sammons, James

    This teacher's guide complements five programs that aired on the Public Broadcasting System (PBS) in the fall of 1999. Programs include: (1) "Fall of the Leaning Tower"; (2) "Everest: The Mystery of Mallory and Irvine"; (3) "Time Travel, Decoding Nazi Secrets"; (3) "Voyage of Doom"; and (5) "Barely Breathing". It provides activity set-ups related…

  16. Inorganic nitrogenous air pollutants, atmospheric nitrogen deposition and their potential ecological impacts in remote areas of western North America (Invited)

    NASA Astrophysics Data System (ADS)

    Bytnerowicz, A.; Fenn, M. E.; Fraczek, W.; Johnson, R.; Allen, E. B.

    2013-12-01

    Dry deposition of gaseous inorganic nitrogenous (N) air pollutants plays an important role in total atmospheric N deposition and its ecological effects in the arid and semi-arid ecosystems. Passive samplers and denuder/ filter pack systems have been used for determining ambient concentrations of ammonia (NH3), nitric oxide (NO), nitrogen dioxide (NO2), and nitric acid vapor (HNO3) in the topographically complex remote areas of the western United States and Canada. Concentrations of the measured pollutants varied significantly between the monitoring areas. Highest NH3, NO2 and HNO3 levels occurred in southern California areas downwind of the Los Angeles Basin and in the western Sierra Nevada impacted by emissions from the California Central Valley and the San Francisco Bay area. Strong spatial gradients of N pollutants were also present in southeastern Alaska due to cruise ship emissions and in the Athabasca Oil Sands Region in Canada affected by oil exploitation. Distribution of these pollutants has been depicted by maps generated by several geostatistical methodologies within the ArcGIS Geostatistical Analyst (ESRI, USA). Such maps help to understand spatial and temporal changes of air pollutants caused by various anthropogenic activities and locally-generated vs. long range-transported air pollutants. Pollution distribution maps for individual N species and gaseous inorganic reactive nitrogen (Nr) have been developed for the southern portion of the Sierra Nevada, Lake Tahoe Basin, San Bernardino Mountains, Joshua Tree National Park and the Athabasca Oil Sands Region. The N air pollution data have been utilized for estimates of dry and total N deposition by a GIS-based inferential method specifically developed for understanding potential ecological impacts in arid and semi-arid areas. The method is based on spatial and temporal distribution of concentrations of major drivers of N dry deposition, their surface deposition velocities and stomatal conductance values

  17. Parametric study of Al and Al 2O 3 ceramic coatings deposited by air plasma spray onto polymer substrate

    NASA Astrophysics Data System (ADS)

    Guanhong, Sun; Xiaodong, He; Jiuxing, Jiang; Yue, Sun

    2011-06-01

    Aluminum and ceramic (Al 2O 3) coatings were deposited onto the polymer substrate by air plasma spray (APS) to improve the mechanical properties of the polymer surface. The effect of spray parameters (current and spray distance in this paper) on the phase composition, microstructure and mechanical properties was investigated. Shear adhesion strength between the coatings and the substrates was also examined. The results indicate that the deposition parameters have a significant effect on the phase composition, microstructure and mechanical properties of as-spayed coatings. The maximum shear adhesion strength of the bond coats was 5.21 MPa with the current of 180 A and 190 mm spray distance.

  18. Lichens as an integrating tool for monitoring PAH atmospheric deposition: a comparison with soil, air and pine needles.

    PubMed

    Augusto, Sofia; Máguas, Cristina; Matos, João; Pereira, Maria João; Branquinho, Cristina

    2010-02-01

    The aim of this study was to validate lichens as biomonitors of PAH atmospheric deposition; for that, an inter-comparison between the PAH profile and concentrations intercepted in lichens with those of air, soil and pine needles was performed. The study was conducted in a petro-industrial area and the results showed that PAH profiles in lichens were similar to those of the air and pine needles, but completely different from those of soils. Lichens accumulated higher PAH concentrations when compared to the other environmental compartments and its concentrations were significantly and linearly correlated with concentrations of PAHs in soil; we showed that a translation of the lichen PAHs concentrations into regulatory standards is possible, fulfilling one of the most important requirements of using lichens as biomonitors. With lichens we were then able to characterize the air PAHs profile of urban, petro-industrial and background areas.

  19. Three air quality studies: Great Lakes ozone formation and nitrogen dry deposition; and Tucson aerosol chemical characterization

    NASA Astrophysics Data System (ADS)

    Foley, Theresa

    (arsenic, beryllium, cadmium, chromium, cobalt, lead, manganese, and nickel) in the southern Tucson metropolitan area. A Tucson company that uses beryllium oxide to manufacture thermally conductive ceramics has prompted strong citizen concern. This study found that the study area has good air quality with respect to PM10 and metals, with ambient concentrations meeting US Environmental Protection Agency and World Health Organization standards. Beryllium was detected only once (during a dust storm) and was ascribed to naturally-occurring beryllium in the suspended soil. The third paper (to be submitted to the Journal of Great Lakes Research) studies nitrogen dry deposition over Lake Michigan and Lake Superior. Numerous studies have shown that wet and dry deposition of nitrogen has contributed to the eutrophication of coastal waters and declining productivity of marine fisheries. Nitrogen dry deposition over the Great Lakes themselves, as opposed to the shorelines, has not been documented in the peer-reviewed literature. This paper calculates nitrogen dry deposition over Lake Michigan and Lake Superior, using aircraft measurements from the LADCO Aircraft Study, and finds that over-water, nitrogen dry deposition is a significant source of nitrogen to Lake Michigan and Lake Superior.

  20. Highly efficient photocatalytic TiO2 coatings deposited by open air atmospheric pressure plasma jet with aerosolized TTIP precursor

    NASA Astrophysics Data System (ADS)

    Fakhouri, H.; Ben Salem, D.; Carton, O.; Pulpytel, J.; Arefi-Khonsari, F.

    2014-07-01

    A simple method to deposit photocatalytic TiO2 coatings, at a high rate (20-40 µm s-1), and with a high porosity, is reported in this paper. This method, which allows the treatment of membranes (with an 800 nm pore size), is based on the introduction of a liquid precursor sprayed into an open-air atmospheric pressure plasma jet (APPJ). The photocatalytic activity of the TiO2 thin films prepared by APPJ have been compared with our best N-doped TiO2 thin films, deposited by reactive radio frequency (RF) magnetron sputtering, previously reported in the literature. The morphology, chemical composition, photoelectrochemical, and photocatalytic properties of the coatings have been studied in this paper. Significant control of the porosity and crystallinity was achieved by varying the deposition parameters and the annealing temperature. Under optimized conditions, the TiO2 coatings deposited by APPJ are characterized by a higher photocatalytic activity as compared to the optimized thin films deposited by RF sputtering. This difference can be explained by the higher specific surface of the APPJ coatings. Finally, the most interesting characteristic of this APPJ-liquid spray process is its capacity to treat membranes without blocking the pores, and to produce photocatalytic membranes which can efficiently combine filtration and photocatalysis for water treatment.

  1. The large-scale distribution and internal geometry of the fall 2000 Po River flood deposit: Evidence from digital X-radiography

    USGS Publications Warehouse

    Wheatcroft, R.A.; Stevens, A.W.; Hunt, L.M.; Milligan, T.G.

    2006-01-01

    Event-response coring on the Po River prodelta (northern Adriatic Sea) coupled with shipboard digital X-radiography, resistivity profiling, and grain-size analyses permitted documentation of the initial distribution and physical properties of the October 2000 flood deposit. The digital X-radiography system comprises a constant-potential X-ray source and an amorphous silicon imager with an active area of 29??42 cm and 12-bit depth resolution. Objective image segmentation algorithms based on bulk density (brightness), layer contacts (edge detection) and small-scale texture (fabric) were used to identify the flood deposit. Results indicate that the deposit formed in water depths of 6-29 m immediately adjacent to the three main distributary mouths of the Po (Pila, Tolle and Gnocca/Goro). Maximal thickness was 36 cm at a 20-m site off the main mouth (Pila), but many other sites hadthicknesses >20 cm. The Po flood deposit has a complex internal stratigraphy, with multiple layers, a diverse suite of physical sedimentary structures (e.g., laminations, ripple cross bedding, lenticular bedding, soft-sediment deformation structures), and dramatic changes in grain size that imply rapid deposition and fluctuations in energy during emplacement. Based on the flood deposit volume and well-constrained measurements of deposit bulk density the mass of the flood deposit was estimated to be 16??109 kg, which is about two-thirds of the estimated suspended sediment load delivered by the river during the event. The locus of deposition, overall thickness, and stratigraphic complexity of the flood deposit can best be explained by the relatively long sediment throughput times of the Po River, whereby sediment is delivered to the ocean during a range of conditions (i.e., the storm responsible for the precipitation is long gone), the majority of which are reflective of the fair-weather condition. Sediment is therefore deposited proximal to the river mouths, where it can form thick, but

  2. Improved Formulations for Air-Surface Exchanges Related to National Security Needs: Dry Deposition Models

    SciTech Connect

    Droppo, James G.

    2006-07-01

    The Department of Homeland Security and others rely on results from atmospheric dispersion models for threat evaluation, event management, and post-event analyses. The ability to simulate dry deposition rates is a crucial part of our emergency preparedness capabilities. Deposited materials pose potential hazards from radioactive shine, inhalation, and ingestion pathways. A reliable characterization of these potential exposures is critical for management and mitigation of these hazards. A review of the current status of dry deposition formulations used in these atmospheric dispersion models was conducted. The formulations for dry deposition of particulate materials from am event such as a radiological attack involving a Radiological Detonation Device (RDD) is considered. The results of this effort are applicable to current emergency preparedness capabilities such as are deployed in the Interagency Modeling and Atmospheric Assessment Center (IMAAC), other similar national/regional emergency response systems, and standalone emergency response models. The review concludes that dry deposition formulations need to consider the full range of particle sizes including: 1) the accumulation mode range (0.1 to 1 micron diameter) and its minimum in deposition velocity, 2) smaller particles (less than .01 micron diameter) deposited mainly by molecular diffusion, 3) 10 to 50 micron diameter particles deposited mainly by impaction and gravitational settling, and 4) larger particles (greater than 100 micron diameter) deposited mainly by gravitational settling. The effects of the local turbulence intensity, particle characteristics, and surface element properties must also be addressed in the formulations. Specific areas for improvements in the dry deposition formulations are 1) capability of simulating near-field dry deposition patterns, 2) capability of addressing the full range of potential particle properties, 3) incorporation of particle surface retention/rebound processes, and

  3. GENERATION, TRANSPORT AND DEPOSITION OF TUNGSTEN-OXIDE AEROSOLS AT 1000 C IN FLOWING AIR-STEAM MIXTURES.

    SciTech Connect

    GREENE,G.A.; FINFROCK,C.C.

    2001-10-01

    Experiments were conducted to measure the rates of oxidation and vaporization of pure tungsten rods in flowing air, steam and air-steam mixtures in laminar flow. Also measured were the downstream transport of tungsten-oxide condensation aerosols and their region of deposition, including plateout in the superheated flow tube, rainout in the condenser and ambient discharge which was collected on an array of sub-micron aerosol filters. The nominal conditions of the tests, with the exception of the first two tests, were tungsten temperatures of 1000 C, gas mixture temperatures of 200 C and wall temperatures of 150 C to 200 C. It was observed that the tungsten oxidation rates were greatest in all air and least in all steam, generally decreasing non-linearly with increasing steam mole fraction. The tungsten oxidation rates in all air were more than five times greater than the tungsten oxidation rates in all steam. The tungsten vaporization rate was zero in all air and increased with increasing steam mole fraction. The vaporization rate became maximum at a steam mole fraction of 0.85 and decreased thereafter as the steam mole fraction was increased to unity. The tungsten-oxide was transported downstream as condensation aerosols, initially flowing upwards from the tungsten rod through an 18-inch long, one-inch diameter quartz tube, around a 3.5-inch radius, 90{sup o} bend and laterally through a 24-inch horizontal run. The entire length of the quartz glass flow path was heated by electrical resistance clamshell heaters whose temperatures were individually controlled and measured. The tungsten-oxide plateout in the quartz tube was collected, nearly all of which was deposited at the end of the heated zone near the entrance to the condenser which was cold. The tungsten-oxide which rained out in the condenser as the steam condensed was collected with the condensate and weighed after being dried. The aerosol smoke which escaped the condenser was collected on the sub

  4. Falling Sticks and Falling Balls

    NASA Astrophysics Data System (ADS)

    Bacon, M. E.; Harpst, Michael R.; Nakazawa, Ryohei

    2002-09-01

    The behavior of a falling stick, pivoted at one end, and a ball released from the same height as the end of the stick, is investigated theoretically and experimentally. The study is made possible through the use of the computer to perform the numerical computations and analysis of the experimental data. The study provides undergraduates with an opportunity to carry out a relatively simple project with interesting results.

  5. Acid deposition in Maryland. Summary of research and monitoring results compiled through 1991 and a discussion of the 1990 Clean Air Act Amendments. Report for 1991-1992

    SciTech Connect

    Price, R.; Mountain, D.

    1992-10-01

    This is the sixth annual report submitted under Maryland legislative requirements. The report focuses on more than a decade of acid deposition research conducted in Maryland. In addition, the report discusses Title IV - Acid Deposition Control of the 1990 Clean Air Act Amendments (CAAA) and its potential impacts on Maryland.

  6. Connecting nitrogen deposition and Final Ecosystem Goods and Services for air quality standards review

    EPA Science Inventory

    There has been a great deal of effort to document changes in ecosystem structure and function in response to increasing or decreasing N deposition, yet less work connects the specific effects on the value to people of these changes in the ecosystem. Although there are studies ta...

  7. Road dust as an indicator for air pollution transport and deposition: An application of SPOT imagery

    SciTech Connect

    Keller, J.; Lamprecht, R.

    1995-10-01

    A simulation model for atmospheric diffusion and dry deposition of coarse dust particles developed at the Paul Scherrer Institute was recently applied to calculate the dispersion and deposition of road-generated dust from the Dalton Highway, which is a high-speed gravel road in arctic Alaska traveled mainly by large vehicles. The propelled dust is deposited on the adjacent vegetation where it may cause detrimental effects to the plants of the highly fragile tundra. During a field experiment in 1991, all meteorological parameters as well as the size distribution of the deposited dust particles were measured. The scope of this article is to identify and, as far as possible, to quantify this dust deposition pattern along the Dalton Highway by multispectral SPOT imagery. The spatial distribution of the dust on both sides of the road is distinctly visible in the XS3 channel (0.79--0.89 {micro}m) of a SPOT satellite image. On the basis of the ground reflectance and the reflectances of pure dust and pure vegetation, the dust load can be calculated. The dust load depends on the particle size distribution, which can be derived from the size spectra measured in the field experiment. The spatial dust load obtained from the SPOT data is compared with the distribution computed with the simulation model. As the simulation is based on only a limited number of days, the dust load scaling is arbitrary. Taking this fact into account, the general shapes of the two distributions agree remarkably well within a strip of about 1 km width along the road. Apart from this application on a local scale, suspended dust might also be detected on larger scales.

  8. The sky is falling II: Impact of deposition produced during the static testing of solid rocket motors on corn and alfalfa.

    PubMed

    Doucette, William J; Mendenhall, Scout; McNeill, Laurie S; Heavilin, Justin

    2014-06-01

    Tests of horizontally restrained rocket motors at the ATK facility in Promontory, Utah, USA result in the deposition of an estimated 1.5million kg of entrained soil and combustion products (mainly aluminum oxide, gaseous hydrogen chloride and water) on the surrounding area. The deposition is referred to as test fire soil (TFS). Farmers observing TFS deposited on their crops expressed concerns regarding the impact of this material. To address these concerns, we exposed corn and alfalfa to TFS collected during a September 2009 test. The impact was evaluated by comparing the growth and tissue composition of controls relative to the treatments. Exposure to TFS, containing elevated levels of chloride (1000 times) and aluminum (2 times) relative to native soils, affected the germination, growth and tissue concentrations of various elements, depending on the type and level of exposure. Germination was inhibited by high concentrations of TFS in soil, but the impact was reduced if the TFS was pre-leached with water. Biomass production was reduced in the TFS amended soils and corn grown in TFS amended soils did not develop kernels. Chloride concentrations in corn and alfalfa grown in TFS amended soils were two orders of magnitude greater than controls. TFS exposed plants contained higher concentrations of several cations, although the concentrations were well below livestock feed recommendations. Foliar applications of TFS had no impact on biomass, but some differences in the elemental composition of leaves relative to controls were observed. Washing the TFS off the leaves lessened the impact. Results indicate that the TFS deposition could have an effect, depending on the amount and growth stage of the crops, but the impact could be mitigated with rainfall or the application of additional irrigation water. The high level of chloride associated with the TFS is the main cause of the observed impacts.

  9. The sky is falling II: Impact of deposition produced during the static testing of solid rocket motors on corn and alfalfa.

    PubMed

    Doucette, William J; Mendenhall, Scout; McNeill, Laurie S; Heavilin, Justin

    2014-06-01

    Tests of horizontally restrained rocket motors at the ATK facility in Promontory, Utah, USA result in the deposition of an estimated 1.5million kg of entrained soil and combustion products (mainly aluminum oxide, gaseous hydrogen chloride and water) on the surrounding area. The deposition is referred to as test fire soil (TFS). Farmers observing TFS deposited on their crops expressed concerns regarding the impact of this material. To address these concerns, we exposed corn and alfalfa to TFS collected during a September 2009 test. The impact was evaluated by comparing the growth and tissue composition of controls relative to the treatments. Exposure to TFS, containing elevated levels of chloride (1000 times) and aluminum (2 times) relative to native soils, affected the germination, growth and tissue concentrations of various elements, depending on the type and level of exposure. Germination was inhibited by high concentrations of TFS in soil, but the impact was reduced if the TFS was pre-leached with water. Biomass production was reduced in the TFS amended soils and corn grown in TFS amended soils did not develop kernels. Chloride concentrations in corn and alfalfa grown in TFS amended soils were two orders of magnitude greater than controls. TFS exposed plants contained higher concentrations of several cations, although the concentrations were well below livestock feed recommendations. Foliar applications of TFS had no impact on biomass, but some differences in the elemental composition of leaves relative to controls were observed. Washing the TFS off the leaves lessened the impact. Results indicate that the TFS deposition could have an effect, depending on the amount and growth stage of the crops, but the impact could be mitigated with rainfall or the application of additional irrigation water. The high level of chloride associated with the TFS is the main cause of the observed impacts. PMID:24632062

  10. Brooktrout Lake case study: biotic recovery from acid deposition 20 years after the 1990 Clean Air Act Amendments.

    PubMed

    Sutherland, James W; Acker, Frank W; Bloomfield, Jay A; Boylen, Charles W; Charles, Donald F; Daniels, Robert A; Eichler, Lawrence W; Farrell, Jeremy L; Feranec, Robert S; Hare, Matthew P; Kanfoush, Sharon L; Preall, Richard J; Quinn, Scott O; Rowell, H Chandler; Schoch, William F; Shaw, William H; Siegfried, Clifford A; Sullivan, Timothy J; Winkler, David A; Nierzwicki-Bauer, Sandra A

    2015-03-01

    The Adirondack Mountain region is an extensive geographic area (26,305 km(2)) in upstate New York where acid deposition has negatively affected water resources for decades and caused the extirpation of local fish populations. The water quality decline and loss of an established brook trout (Salvelinus fontinalis [Mitchill]) population in Brooktrout Lake were reconstructed from historical information dating back to the late 1880s. Water quality and biotic recovery were documented in Brooktrout Lake in response to reductions of S deposition during the 1980s, 1990s, and 2000s and provided a unique scientific opportunity to re-introduce fish in 2005 and examine their critical role in the recovery of food webs affected by acid deposition. Using C and N isotope analysis of fish collagen and state hatchery feed as well as Bayesian assignment tests of microsatellite genotypes, we document in situ brook trout reproduction, which is the initial phase in the restoration of a preacidification food web structure in Brooktrout Lake. Combined with sulfur dioxide emissions reductions promulgated by the 1990 Clean Air Act Amendments, our results suggest that other acid-affected Adirondack waters could benefit from careful fish re-introduction protocols to initiate the ecosystem reconstruction of important components of food web dimensionality and functionality.

  11. An electrical conductivity based method of determining the particle deposition rate in air-liquid interface devices.

    PubMed

    Wiegand, Harald; Meyer, Jörg; Kasper, Gerhard

    2015-08-01

    A new in-situ method of determining the particle deposition rate onto cell cultures inside air-liquid interface devices is described. It is based on depositing a surrogate aerosol of salt particles onto the water filled wells of a culture plate while measuring the resulting change in electrical conductivity of the solution in situ, in order to derive the accumulated particle mass. For evaluation purposes, the wells of a six-well cell culture plate were equipped with custom designed electrodes and calibrated with a series of commercially available standard solutions. After the necessary corrections prescribed by theory, the calibration resulted in an accuracy and comparability between cells of ±3% in terms of measured conductivity. The method was then applied to a specific ALI device consisting essentially of the calibrated six-well culture plate inside an electrostatic cross-flow precipitator, and tested with submicron NaCl aerosol of defined size distribution produced by nebulization of a salt solution. 2h of particle accumulation were sufficient to accumulate between 30 and 10 μg of salt per well, depending on the location in the precipitator. Resulting deposition rates varied narrowly between the wells by about 2 ng min(-1) cm(-2). Factors affecting the overall accuracy and reproducibility are discussed.

  12. Brooktrout Lake case study: biotic recovery from acid deposition 20 years after the 1990 Clean Air Act Amendments.

    PubMed

    Sutherland, James W; Acker, Frank W; Bloomfield, Jay A; Boylen, Charles W; Charles, Donald F; Daniels, Robert A; Eichler, Lawrence W; Farrell, Jeremy L; Feranec, Robert S; Hare, Matthew P; Kanfoush, Sharon L; Preall, Richard J; Quinn, Scott O; Rowell, H Chandler; Schoch, William F; Shaw, William H; Siegfried, Clifford A; Sullivan, Timothy J; Winkler, David A; Nierzwicki-Bauer, Sandra A

    2015-03-01

    The Adirondack Mountain region is an extensive geographic area (26,305 km(2)) in upstate New York where acid deposition has negatively affected water resources for decades and caused the extirpation of local fish populations. The water quality decline and loss of an established brook trout (Salvelinus fontinalis [Mitchill]) population in Brooktrout Lake were reconstructed from historical information dating back to the late 1880s. Water quality and biotic recovery were documented in Brooktrout Lake in response to reductions of S deposition during the 1980s, 1990s, and 2000s and provided a unique scientific opportunity to re-introduce fish in 2005 and examine their critical role in the recovery of food webs affected by acid deposition. Using C and N isotope analysis of fish collagen and state hatchery feed as well as Bayesian assignment tests of microsatellite genotypes, we document in situ brook trout reproduction, which is the initial phase in the restoration of a preacidification food web structure in Brooktrout Lake. Combined with sulfur dioxide emissions reductions promulgated by the 1990 Clean Air Act Amendments, our results suggest that other acid-affected Adirondack waters could benefit from careful fish re-introduction protocols to initiate the ecosystem reconstruction of important components of food web dimensionality and functionality. PMID:25621941

  13. Image analysis of epicuticular damage to foliage caused by dry deposition of the air pollutant nitric acid.

    PubMed

    Padgett, Pamela E; Parry, Sally D; Bytnerowicz, Andrzej; Heath, Robert L

    2009-01-01

    Nitric acid vapor is produced by the same photochemical processes that produce ozone. In the laboratory, concentrated nitric acid is a strong acid and a powerful oxidant. In the environment, where the concentrations are much lower, it is an innocuous source of plant nitrogen. As an air pollutant, which mode of action does dry deposition of nitric acid follow? We investigated the effects of dry deposition of nitric acid on the foliage of four tree species native to the western United States. A novel controlled environment, fumigation system enabled a four-week exposure at concentrations consistent with ambient diurnal patterns. Scanning electron microscopy and automated image analysis revealed changes in the epicuticular wax layer during fumigation. Exposure to nitric acid resulted in a reproducible suite of damage symptoms that increased with increasing dose. Each tree species tested exhibited a unique set of damage features, including cracks, lesions, and conformation changes to epicuticular crystallite structures. Dry deposition of atmospheric nitric acid caused substantial perturbation to the epicuticular surface of all four tree species investigated, consistent with the chemical oxidation of epicuticular waxes. Automated image analysis eliminated many biases that can trouble microscopy studies. Trade names and commercial enterprises or products are mentioned solely for information. No endorsements by the U.S. Department of Agriculture are implied.

  14. Arctic tundra shrub invasion and soot deposition: Consequences for spring snowmelt and near-surface air temperatures

    NASA Astrophysics Data System (ADS)

    Strack, John E.

    Invasive shrubs and soot pollution both have the potential to alter the surface energy balance and timing of snow melt in the Arctic. Shrubs reduce the amount of snow lost to sublimation on the tundra during the winter leading to a deeper end-of-winter snowpack. The shrubs also enhance the absorption of energy by the snowpack during the melt season, by converting incoming solar radiation to longwave radiation and sensible heat. This results in a faster rate of snow melt, warmer near-surface air temperatures, and a deeper boundary layer. Soot deposition lowers the albedo of the snow allowing it to more effectively absorb incoming solar radiation and thus melt faster. This study uses the Colorado State University Regional Atmospheric Modeling System version 4.4 (CSU-RAMS 4.4), equipped with an enhanced snow model, to investigate the effects of shrub encroachment and soot deposition on the atmosphere and snowpack in the Kuparuk Basin of Alaska during the May-June melt period. The results of the simulations suggest that a complete invasion of the tundra by shrubs leads to a 1.5 degree C warming of 2-m air temperatures, 17 watts per meter square increase in surface sensible heat flux, and a 108 m increase in boundary layer depth during the melt period. The snow free-date also occurred 11 days earlier despite having a larger initial snowpack. The results also show that a decrease in the snow albedo of 0.1, due to soot pollution, caused the snow-free date to occur five days earlier. The soot pollution caused a 0.5 degree C warming of 2-m air temperatures and a 2 watts per meter square increase in surface sensible heat flux. In addition, the boundary layer averaged 25 m deeper in the polluted snow simulation.

  15. ANEMOS: A computer code to estimate air concentrations and ground deposition rates for atmospheric nuclides emitted from multiple operating sources

    SciTech Connect

    Miller, C.W.; Sjoreen, A.L.; Begovich, C.L.; Hermann, O.W.

    1986-11-01

    This code estimates concentrations in air and ground deposition rates for Atmospheric Nuclides Emitted from Multiple Operating Sources. ANEMOS is one component of an integrated Computerized Radiological Risk Investigation System (CRRIS) developed for the US Environmental Protection Agency (EPA) for use in performing radiological assessments and in developing radiation standards. The concentrations and deposition rates calculated by ANEMOS are used in subsequent portions of the CRRIS for estimating doses and risks to man. The calculations made in ANEMOS are based on the use of a straight-line Gaussian plume atmospheric dispersion model with both dry and wet deposition parameter options. The code will accommodate a ground-level or elevated point and area source or windblown source. Adjustments may be made during the calculations for surface roughness, building wake effects, terrain height, wind speed at the height of release, the variation in plume rise as a function of downwind distance, and the in-growth and decay of daughter products in the plume as it travels downwind. ANEMOS can also accommodate multiple particle sizes and clearance classes, and it may be used to calculate the dose from a finite plume of gamma-ray-emitting radionuclides passing overhead. The output of this code is presented for 16 sectors of a circular grid. ANEMOS can calculate both the sector-average concentrations and deposition rates at a given set of downwind distances in each sector and the average of these quantities over an area within each sector bounded by two successive downwind distances. ANEMOS is designed to be used primarily for continuous, long-term radionuclide releases. This report describes the models used in the code, their computer implementation, the uncertainty associated with their use, and the use of ANEMOS in conjunction with other codes in the CRRIS. A listing of the code is included in Appendix C.

  16. Integrated evaluation of aerogenic pollution by air-transported heavy metals (Pb, Cd, Ni, Zn, Mn and Cu) in the analysis of the main deposit media.

    PubMed

    Baltrėnaitė, Edita; Baltrėnas, Pranas; Lietuvninkas, Arvydas; Serevičienė, Vaida; Zuokaitė, Eglė

    2014-01-01

    The composition of the ambient air is constantly changing; therefore, the monitoring of ambient air quality to detect the changes caused by aerogenic pollutants makes the essential part of general environmental monitoring. To achieve more effective improvement of the ambient air quality, the Directive 2008/50/EC on 'Ambient Air Quality and Cleaner Air for Europe' was adopted by the European Parliament and the European Council. It informed the public and enterprises about a negative effect of pollution on humans, animals and plants, as well as about the need for monitoring aerogenic pollutants not only at the continuous monitoring stations but also by using indicator methods, i.e. by analysing natural deposit media. The problem of determining the relationship between the accumulation level of pollutants by a deposit medium and the level of air pollution and its risks is constantly growing in importance. The paper presents a comprehensive analysis of the response of the main four deposit media, i.e. snow cover, soil, pine bark and epigeic mosses, to the long-term pollution by aerogenic pollutants which can be observed in the area of oil refinery influence. Based on the quantitative expressions of the amounts of the accumulated pollutants in the deposit media, the territory of the oil refinery investigated in this paper has been referred to the areas of mild or moderate pollution.

  17. A Piece of Paper Falling Faster than Free Fall

    ERIC Educational Resources Information Center

    Vera, F.; Rivera, R.

    2011-01-01

    We report a simple experiment that clearly demonstrates a common error in the explanation of the classic experiment where a small piece of paper is put over a book and the system is let fall. This classic demonstration is used in introductory physics courses to show that after eliminating the friction force with the air, the piece of paper falls…

  18. Microstructural study of as sprayed and heat treated Ni3Al coatings deposited by air plasma spraying technique

    NASA Astrophysics Data System (ADS)

    Mehmood, K.; Rafiq, M. A.; Nusair Khan, A.; Rauf, M. M.

    2016-08-01

    Air plasma spraying system was utilized to deposit Ni3Al coatings on AISI 321 steel samples. After plasma spraying the coatings were heat treated at different temperatures i.e. 500 °C to 800 °C for 10 to 100 hours. The characterization tools such as, X-Ray diffraction analysis, optical and scanning electron microscopy were used. By comparing the XRD scan data of as sprayed and heat treated coating, it was observed that the formation of NiO increases drastically with time and temperature. Due to the formation of NiO, hardness was also enhanced. The oxidation behavior was observed by using optical microscope and when it was studied that the oxidation was increasing with time and temperature. Further, the SEM tool was utilized to study the detail microstructural behavior such as shrinkage cavity and oxide particles. The other phases like alumina and spinel phases were determined by using Energy dispersive spectrometer method.

  19. How air influences radiation dose deposition in multiwell culture plates: a Monte Carlo simulation of radiation geometry.

    PubMed

    Sabater, Sebastia; Berenguer, Roberto; Honrubia-Gomez, Paloma; Rivera, Miguel; Nuñez, Ana; Jimenez-Jimenez, Esther; Martos, Ana; Ramirez-Castillejo, Carmen

    2014-09-01

    Radiation of experimental culture cells on plates with various wells can cause a risk of underdosage as a result of the existence of multiple air-water interfaces. The objective of our study was to quantify this error in culture plates with multiple wells. Radiation conditions were simulated with the GAMOS code, based on the GEANT4 code, and this was compared with a simulation performed with PENELOPE and measured data. We observed a slight underdosage of ∼ 4% on the most superficial half of the culture medium. We believe that this underdosage does not have a significant effect on the dose received by culture cells deposited in a monolayer and adhered to the base of the wells.

  20. In situ and air index measurements: influence of the deposition parameters on the shift of TiO2/SiO2 Fabry-Perot filters.

    PubMed

    Schmitt, B; Borgogno, J P; Albrand, G; Pelletier, E

    1986-11-01

    We measure the refractive index of thin films of TiO2 and SiO2 for given deposition parameters. Two complementary methods are used. The first is a postdeposition technique which uses the measurements of reflectance and transmittance in air. The second, in contrast, makes use of in situ measurements (under vacuum and during the actual deposition of the layer). The differences between the values deduced from the two methods can be explained by the amount of atmospheric moisture adsorbed by films. One tries to minimize these shifts for the two materials by choosing deposition parameters. The difficulties come from the absorption losses which must be as small as possible. We use the measured refractive indices of individual layers to give good numerical prediction of the wavelength shift (observed during the admittance of air after deposition in the vacuum chamber) of the transmittance peak of multidielectric Fabry-Perot filters.

  1. Granulometric and magnetic properties of deposited particles in the Beijing subway and the implications for air quality management.

    PubMed

    Cui, Guipeng; Zhou, Liping; Dearing, John

    2016-10-15

    The subway system is an important traffic facility in Beijing and its internal air quality is an environmental issue that could potentially affect millions of people every day. Due to the intrinsic nature of rail abrasion in subway tunnels, iron-containing particles can be generated and become suspended in the subway environment. While some studies (e.g. Li et al., 2006) have monitored the in-train levels of PM2.5 (particles<2.5μm), there is a lack of systematic assessment of the concentration and characteristics of iron-containing particles in the Beijing subway system. Here we report results of a study on the granulometric and magnetic properties of deposited particle samples collected at different localities of the Beijing subway system. Our results show that the subway samples are characterized by the presence of fine particles. Volume proportions of 6.1±1.3% for particles<2.5μm and 27.5±6.1% for particles<10μm are found in the bulk subway samples. These samples exhibit a strong magnetic signal, which is approximately two orders of magnitude higher than that in naturally deposited particles collected in Beijing. Fine grained ferromagnetic and ferrimagnetic minerals (e.g. iron and magnetite, respectively) are identified from mineral magnetic measurements and scanning electric microscopy. The samples collected from the Beijing stations with platform screen doors are found to be magnetically stronger and finer than those without them, suggesting that platform screen doors have failed to block the fine iron-containing particles released from the rail tunnel. Given the potential health consequences of fine suspended iron-containing particles, our results have important implications for air quality management in the Beijing subway system. PMID:27372891

  2. Arctic tundra shrub invasion and soot deposition: Consequences for spring snowmelt and near-surface air temperatures

    NASA Astrophysics Data System (ADS)

    Strack, John E.; Pielke, Roger A.; Liston, Glen E.

    2007-12-01

    Invasive shrubs and soot pollution both have the potential to alter the surface energy balance and timing of snow melt in the Arctic. Shrubs reduce the amount of snow lost to sublimation on the tundra during the winter leading to a deeper end-of-winter snowpack. The shrubs also enhance the absorption of energy by the snowpack during the melt season by converting incoming solar radiation to longwave radiation and sensible heat. Soot deposition lowers the albedo of the snow, allowing it to more effectively absorb incoming solar radiation and thus melt faster. This study uses the Colorado State University Regional Atmospheric Modeling System version 4.4 (CSU-RAMS 4.4), equipped with an enhanced snow model, to investigate the effects of shrub encroachment and soot deposition on the atmosphere and snowpack in the Kuparuk Basin of Alaska during the May-June melt period. The results of the simulations suggest that a complete invasion of the tundra by shrubs leads to a 2.2°C warming of 3 m air temperatures and a 108 m increase in boundary layer depth during the melt period. The snow-free date also occurred 11 d earlier despite having a larger initial snowpack. The results also show that a decrease in the snow albedo of 0.1, owing to soot pollution, caused the snow-free date to occur 5 d earlier. The soot pollution caused a 1.0°C warming of 3 m air temperatures and a 25 m average deepening of the boundary layer.

  3. Granulometric and magnetic properties of deposited particles in the Beijing subway and the implications for air quality management.

    PubMed

    Cui, Guipeng; Zhou, Liping; Dearing, John

    2016-10-15

    The subway system is an important traffic facility in Beijing and its internal air quality is an environmental issue that could potentially affect millions of people every day. Due to the intrinsic nature of rail abrasion in subway tunnels, iron-containing particles can be generated and become suspended in the subway environment. While some studies (e.g. Li et al., 2006) have monitored the in-train levels of PM2.5 (particles<2.5μm), there is a lack of systematic assessment of the concentration and characteristics of iron-containing particles in the Beijing subway system. Here we report results of a study on the granulometric and magnetic properties of deposited particle samples collected at different localities of the Beijing subway system. Our results show that the subway samples are characterized by the presence of fine particles. Volume proportions of 6.1±1.3% for particles<2.5μm and 27.5±6.1% for particles<10μm are found in the bulk subway samples. These samples exhibit a strong magnetic signal, which is approximately two orders of magnitude higher than that in naturally deposited particles collected in Beijing. Fine grained ferromagnetic and ferrimagnetic minerals (e.g. iron and magnetite, respectively) are identified from mineral magnetic measurements and scanning electric microscopy. The samples collected from the Beijing stations with platform screen doors are found to be magnetically stronger and finer than those without them, suggesting that platform screen doors have failed to block the fine iron-containing particles released from the rail tunnel. Given the potential health consequences of fine suspended iron-containing particles, our results have important implications for air quality management in the Beijing subway system.

  4. NOVA Fall 2000 Teacher's Guide.

    ERIC Educational Resources Information Center

    Ransick, Kristina; Rosene, Dale; Sammons, Fran Lyons; Sammons, James

    This teacher's guide complements six programs that aired on the Public Broadcasting System (PBS) in the fall of 2000. Programs include: (1) "Lincoln's Secret Weapon"; (2) "Hitler's Lost Sub"; (3) "Runaway Universe"; (4) "Garden of Eden"; (5) "Dying to Be Thin"; and (6) "Japan's Secret Garden". It provides activity set-ups related to the programs…

  5. Characterization and Wear Behavior of Heat-treated Ni3Al Coatings Deposited by Air Plasma Spraying

    NASA Astrophysics Data System (ADS)

    Mehmood, K.; Rafiq, M. A.; Nusair Khan, A.; Ahmed, F.; Mudassar Rauf, M.

    2016-07-01

    Air plasma spraying was utilized to deposit Ni3Al coatings on AISI-321 steel substrate. The deposited coatings were isothermally heat-treated at various temperatures from 500 to 800 °C for 10, 30, 60, and 100 h. The x-ray diffraction analysis revealed NiO formation in Ni3Al at 500 °C after 100 h, and the percentage of NiO increased with increasing exposure time and temperature. The hardness of the coating increased with the formation of NiO. The DSC test showed the formation of minor phases, Al3Ni and Al3Ni2, within the coating along with the major phase Ni3Al. TGA revealed a slowing down of the oxidation rate upon surface oxide formation. The pin-on-disk wear test on the as-sprayed and heat-treated coatings showed that wear rate and coefficient of friction decreased with an increase in the NiO phase content.

  6. Effects and uptake of gold nanoparticles deposited at the air-liquid interface of a human epithelial airway model

    SciTech Connect

    Brandenberger, C.; Rothen-Rutishauser, B.; Muehlfeld, C.; Schmid, O.; Ferron, G.A.; Maier, K.L.; Gehr, P.; Lenz, A.-G.

    2010-01-01

    The impact of nanoparticles (NPs) in medicine and biology has increased rapidly in recent years. Gold NPs have advantageous properties such as chemical stability, high electron density and affinity to biomolecules, making them very promising candidates as drug carriers and diagnostic tools. However, diverse studies on the toxicity of gold NPs have reported contradictory results. To address this issue, a triple cell co-culture model simulating the alveolar lung epithelium was used and exposed at the air-liquid interface. The cell cultures were exposed to characterized aerosols with 15 nm gold particles (61 ng Au/cm{sup 2} and 561 ng Au/cm{sup 2} deposition) and incubated for 4 h and 24 h. Experiments were repeated six times. The mRNA induction of pro-inflammatory (TNFalpha, IL-8, iNOS) and oxidative stress markers (HO-1, SOD2) was measured, as well as protein induction of pro- and anti-inflammatory cytokines (IL-1, IL-2, IL-4, IL-6, IL-8, IL-10, GM-CSF, TNFalpha, INFgamma). A pre-stimulation with lipopolysaccharide (LPS) was performed to further study the effects of particles under inflammatory conditions. Particle deposition and particle uptake by cells were analyzed by transmission electron microscopy and design-based stereology. A homogeneous deposition was revealed, and particles were found to enter all cell types. No mRNA induction due to particles was observed for all markers. The cell culture system was sensitive to LPS but gold particles did not cause any synergistic or suppressive effects. With this experimental setup, reflecting the physiological conditions more precisely, no adverse effects from gold NPs were observed. However, chronic studies under in vivo conditions are needed to entirely exclude adverse effects.

  7. Long-Term Response of High-Elevation Lakes to Changes in Atmospheric Deposition and Air Temperature

    NASA Astrophysics Data System (ADS)

    Mast, M.; Turk, J. T.; Campbell, D. H.; Clow, D. W.; Ingersoll, G. P.

    2008-12-01

    High-elevation lakes are often sensitive indicators of environmental and climate change. Here we evaluate over two decades of water-quality data from a long-term monitoring network of remote high-mountain lakes in three Colorado wilderness areas. In two of the areas, lake sulfate concentrations have decreased by a factor of 2-3 times since the mid-1980s, which is consistent with declines in precipitation sulfate measured at 11 high-elevation NADP stations in Colorado. The downward trends in lake and precipitation chemistry are likely the result of regional declines in sulfate emissions from power plants and nonferrous metal smelters. By contrast, lake sulfate concentrations increased dramatically in the third wilderness area despite declines in atmospherically deposited sulfate. In lakes in these areas, sulfate is derived primarily from pyrite oxidation in contrast to the other wilderness areas where sulfate is dominated by atmospheric sources. It is hypothesized that the upward trend in sulfate reflects enhanced pyrite weathering caused by an increase in annual air temperature of about 2-degrees Celsius since the mid-1980's. These results indicate the water-quality response of remote lakes to improvements in air quality may be complicated by long-term changes in climate.

  8. Pulsed nanosecond discharge in air at high specific deposited energy: fast gas heating and active particle production

    NASA Astrophysics Data System (ADS)

    Popov, N. A.

    2016-08-01

    The results of a numerical study on kinetic processes initiated by a pulsed nanosecond discharge in air at high specific deposited energy, when the dissociation degree of oxygen molecules is high, are presented. The calculations of the temporal dynamics of the electron concentration, density of atomic oxygen, vibrational distribution function of nitrogen molecules, and gas temperature agree with the experimental data. It is shown that quenching of electronically excited states of nitrogen N2(B3Πg), N2(C3Πu), N2(a‧1 Σ \\text{u}- ) by oxygen molecules leads to the dissociation of O2. This conclusion is based on the comparison of calculated dynamics of atomic oxygen in air, excited by a pulsed nanosecond discharge, with experimental data. In air plasma at a high dissociation degree of oxygen molecules ([O]/[O2] > 10%), relaxation of the electronic energy of atoms and molecules in reactions with O atoms becomes extremely important. Active production of NO molecules and fast gas heating in the discharge plasma due to the quenching of electronically excited N2(B3Πg, C3Πu, a‧1 Σ \\text{u}- ) molecules by oxygen atoms is notable. Owing to the high O atom density, electrons are effectively detached from negative ions in the discharge afterglow. As a result, the decay of plasma in the afterglow is determined by electron-ion recombination, and the electron density remains relatively high between the pulses. An increase in the vibrational temperature of nitrogen molecules at the periphery of the plasma channel at time delay t = 1-30 μs after the discharge is obtained. This is due to intense gas heating and, as a result, gas-dynamic expansion of a hot gas channel. Vibrationally excited N2(v) molecules produced near the discharge axis move from the axial region to the periphery. Consequently, at the periphery the vibrational temperature of nitrogen molecules is increased.

  9. Eddy covariance flux of sulfur dioxide to the sea surface: Air-side resistance to deposition of a highly soluble gas

    NASA Astrophysics Data System (ADS)

    Porter, J.; De Bruyn, W. J.; Miller, S. D.; Saltzman, E. S.

    2014-12-01

    Deposition to the sea surface represents a major atmospheric removal mechanism for sulfur dioxide and many other highly soluble products of tropospheric photochemistry. Such gases include nitric acid, ammonia, organic acids, sulfur dioxide, and highly soluble organic compounds such as methanol and acetone. The deposition of highly soluble gases is controlled by turbulent and diffusive transport on the air side of the air/sea interface. In this study, air/sea fluxes of the soluble gas sulfur dioxide (SO2 ), sensible and latent heat, and momentum were measured using eddy covariance. This was a pilot study carried out in April 2014 on Scripps pier in La Jolla, California, that was designed to assess the potential for measuring SO2 fluxes over the ocean. SO2 was detected using chemical ion mass spectrometry in negative ion mode with a sensitivity of roughly 100 Hz/ppt. The ionization scheme involved addition of ozone to a dried air stream and subsequent conversion of SO2 to the SO5 - ion. The results demonstrate the feasibility of seagoing SO2 flux measurements. Such measurements can be used to constrain the depositional velocities of soluble gases and test models for air-side resistance to air/sea gas transfer.

  10. Changing trends in sulfur emissions in Asia: implications for acid deposition, air pollution, and climate.

    PubMed

    Carmichael, Gregory R; Streets, David G; Calori, Giuseppe; Amann, Markus; Jacobson, Mark Z; Hansen, James; Ueda, Hiromasa

    2002-11-15

    In the early 1990s, it was projected that annual SO2 emissions in Asia might grow to 80-110 Tg yr(-1) by 2020. Based on new high-resolution estimates from 1975 to 2000, we calculate that SO2 emissions in Asia might grow only to 40-45 Tg yr(-1) by 2020. The main reason for this lower estimate is a decline of SO2 emissions from 1995 to 2000 in China, which emits about two-thirds of Asian SO2. The decline was due to a reduction in industrial coal use, a slowdown of the Chinese economy, and the closure of small and inefficient plants, among other reasons. One effect of the reduction in SO2 emissions in China has been a reduction in acid deposition not only in China but also in Japan. Reductions should also improve visibility and reduce health problems. SO2 emission reductions may increase global warming, but this warming effect could be partially offset by reductions in the emissions of black carbon. How SO2 emissions in the region change in the coming decades will depend on many competing factors (economic growth, pollution control laws, etc.). However a continuation of current trends would result in sulfur emissions lower than any IPCC forecasts.

  11. Falls and Older Adults

    MedlinePlus

    ... rises with age. Click for more information Falls Lead to Fractures, Trauma Each year, more than 1. ... and injury deaths. Fractures caused by falls can lead to hospital stays and disability. Most often, fall- ...

  12. Falls in Nursing Homes

    MedlinePlus

    ... for health care providers. Learn More Falls in Nursing Homes Recommend on Facebook Tweet Share Compartir On ... 5 Why do falls occur more often in nursing homes? Falling can be a sign of other ...

  13. Influence of air mass origin on the wet deposition of nitrogen to Tampa Bay, Florida—An eight-year study

    NASA Astrophysics Data System (ADS)

    Strayer, Hillary; Smith, Ronald; Mizak, Connie; Poor, Noreen

    Rainfall delivers on the average ˜10% of the total annual nitrogen load directly to Tampa Bay, based on precipitation monitoring at a National Atmospheric Deposition Program (NADP) Atmospheric Integrated Research Monitoring Network (AIRMoN) site located adjacent to Tampa Bay in urban Tampa. We coupled the chemical analyses for 606 daily precipitation samples collected from 1996 to 2004 with corresponding air mass trajectory information to investigate if wet-deposited nitrogen originated from near versus removed source regions. Air mass trajectories were obtained using the National Oceanic and Atmospheric Administration (NOAA) HYbrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model, and were classified into six trajectory categories by the direction of their approach to Tampa Bay. Rainfall nitrate and ammonium concentrations were significantly lower for over-water air mass trajectories than for over-land trajectories as expected, but contributed to 40% of the total wet-deposited nitrogen, a likely consequence of the higher frequency of rain events for these trajectories. Average rainfall nitrate concentrations were significantly higher for air masses that stagnated over the urbanized bay region. We estimated that local sources contributed 1kgNha-1yr-1 or 25% of the total inorganic nitrogen wet-deposited to Tampa Bay.

  14. A Multi-Resolution Assessment of the Community Multiscale Air Quality (CMAQ) Model v4.7 Wet Deposition Estimates for 2002 - 2006

    EPA Science Inventory

    This paper examines the operational performance of the Community Multiscale Air Quality (CMAQ) model simulations for 2002 - 2006 using both 36-km and 12-km horizontal grid spacing, with a primary focus on the performance of the CMAQ model in predicting wet deposition of sulfate (...

  15. Trends in visibility, PM{sub 2.5}, and deposition expected from the Acid Rain Provisions of the 1990 Clean Air Act Amendments

    SciTech Connect

    Shannon, J.D.; Hanson, D.A.

    1997-08-01

    The Acid Rain Provisions (Title IV) of the 1990 Clean Air Act Amendments (CAAA) are designed to reduce the deposition of SO{sub 2} and sulfate and, to a lesser extent, the deposition of NO{sub x} and nitrate through reduction of SO{sub 2} and NO{sub x} emissions. However, other important benefits are anticipated from the emission control strategies, including improvement of regional visibility and reductions in concentrations of fine particles (PM2.5). In this study, the authors coupled utility emissions forecasts with the Advanced Statistical Trajectory Regional Air Pollution (ASTRAP) model and the Visibility Assessment Scoping Model (VASM) to calculate and compare the relative improvements by 2010 in visual impairment, PM2.5 concentrations, and sulfate wet deposition at selected sites in the eastern United States.

  16. A method to assess the inter-annual weather-dependent variability in air pollution concentration and deposition based on weather typing

    NASA Astrophysics Data System (ADS)

    Pleijel, Håkan; Grundström, Maria; Karlsson, Gunilla Pihl; Karlsson, Per Erik; Chen, Deliang

    2016-02-01

    Annual anomalies in air pollutant concentrations, and deposition (bulk and throughfall) of sulphate, nitrate and ammonium, in the Gothenburg region, south-west Sweden, were correlated with optimized linear combinations of the yearly frequency of Lamb Weather Types (LWTs) to determine the extent to which the year-to-year variation in pollution exposure can be partly explained by weather related variability. Air concentrations of urban NO2, CO, PM10, as well as O3 at both an urban and a rural monitoring site, and the deposition of sulphate, nitrate and ammonium for the period 1997-2010 were included in the analysis. Linear detrending of the time series was performed to estimate trend-independent anomalies. These estimated anomalies were subtracted from observed annual values. Then the statistical significance of temporal trends with and without LWT adjustment was tested. For the pollutants studied, the annual anomaly was well correlated with the annual LWT combination (R2 in the range 0.52-0.90). Some negative (annual average [NO2], ammonia bulk deposition) or positive (average urban [O3]) temporal trends became statistically significant (p < 0.05) when the LWT adjustment was applied. In all the cases but one (NH4 throughfall, for which no temporal trend existed) the significance of temporal trends became stronger with LWT adjustment. For nitrate and ammonium, the LWT based adjustment explained a larger fraction of the inter-annual variation for bulk deposition than for throughfall. This is probably linked to the longer time scale of canopy related dry deposition processes influencing throughfall being explained to a lesser extent by LWTs than the meteorological factors controlling bulk deposition. The proposed novel methodology can be used by authorities responsible for air pollution management, and by researchers studying temporal trends in pollution, to evaluate e.g. the relative importance of changes in emissions and weather variability in annual air pollution

  17. Pulsed nanosecond discharge in air at high specific deposited energy: fast gas heating and active particle production

    NASA Astrophysics Data System (ADS)

    Popov, N. A.

    2016-08-01

    The results of a numerical study on kinetic processes initiated by a pulsed nanosecond discharge in air at high specific deposited energy, when the dissociation degree of oxygen molecules is high, are presented. The calculations of the temporal dynamics of the electron concentration, density of atomic oxygen, vibrational distribution function of nitrogen molecules, and gas temperature agree with the experimental data. It is shown that quenching of electronically excited states of nitrogen N2(B3Πg), N2(С3Πu), N2(a‧1 Σ \\text{u}- ) by oxygen molecules leads to the dissociation of O2. This conclusion is based on the comparison of calculated dynamics of atomic oxygen in air, excited by a pulsed nanosecond discharge, with experimental data. In air plasma at a high dissociation degree of oxygen molecules ([O]/[O2]  >  10%), relaxation of the electronic energy of atoms and molecules in reactions with O atoms becomes extremely important. Active production of NO molecules and fast gas heating in the discharge plasma due to the quenching of electronically excited N2(B3Πg, C3Πu, a‧1 Σ \\text{u}- ) molecules by oxygen atoms is notable. Owing to the high O atom density, electrons are effectively detached from negative ions in the discharge afterglow. As a result, the decay of plasma in the afterglow is determined by electron–ion recombination, and the electron density remains relatively high between the pulses. An increase in the vibrational temperature of nitrogen molecules at the periphery of the plasma channel at time delay t  =  1–30 μs after the discharge is obtained. This is due to intense gas heating and, as a result, gas-dynamic expansion of a hot gas channel. Vibrationally excited N2(v) molecules produced near the discharge axis move from the axial region to the periphery. Consequently, at the periphery the vibrational temperature of nitrogen molecules is increased.

  18. Changes in future air quality, deposition, and aerosol-cloud interactions under future climate and emission scenarios

    NASA Astrophysics Data System (ADS)

    Glotfelty, Timothy; Zhang, Yang; Karamchandani, Prakash; Streets, David G.

    2016-08-01

    The prospect of global climate change will have wide scale impacts, such as ecological stress and human health hazards. One aspect of concern is future changes in air quality that will result from changes in both meteorological forcing and air pollutant emissions. In this study, the GU-WRF/Chem model is employed to simulate the impact of changing climate and emissions following the IPCC AR4 SRES A1B scenario. An average of 4 future years (2020, 2030, 2040, and 2050) is compared against an average of 2 current years (2001 and 2010). Under this scenario, by the Mid-21st century global air quality is projected to degrade with a global average increase of 2.5 ppb in the maximum 8-hr O3 level and of 0.3 μg m-3 in 24-hr average PM2.5. However, PM2.5 changes are more regional due to regional variations in primary aerosol emissions and emissions of gaseous precursor for secondary PM2.5. Increasing NOx emissions in this scenario combines with a wetter climate elevating levels of OH, HO2, H2O2, and the nitrate radical and increasing the atmosphere's near surface oxidation state. This differs from findings under the RCP scenarios that experience declines in OH from reduced NOx emissions, stratospheric recovery of O3, and increases in CH4 and VOCs. Increasing NOx and O3 levels enhances the nitrogen and O3 deposition, indicating potentially enhanced crop damage and ecosystem stress under this scenario. The enhanced global aerosol level results in enhancements in aerosol optical depth, cloud droplet number concentration, and cloud optical thickness. This leads to dimming at the Earth's surface with a global average reduction in shortwave radiation of 1.2 W m-2. This enhanced dimming leads to a more moderate warming trend and different trends in radiation than those found in NCAR's CCSM simulation, which does not include the advanced chemistry and aerosol treatment of GU-WRF/Chem and cannot simulate the impacts of changing climate and emissions with the same level of detailed

  19. Fall Enrollment Report. 2014

    ERIC Educational Resources Information Center

    Iowa Department of Education, 2014

    2014-01-01

    This report summarizes and analyzes fall enrollment in Iowa's community colleges. Each year, Iowa's 15 community colleges submit data on enrollment on the 10th business day of the fall semester. Some highlights from this report include: (1) Fall 2014 enrollment was 93,772 students--a decline of 0.49 percent from last fall; (2) Enrollment continues…

  20. Growth of CdS thin films on indium coated glass substrates via chemical bath deposition and subsequent air annealing

    NASA Astrophysics Data System (ADS)

    Ghosh, Biswajit; Kumar, Kamlesh; Singh, Balwant Kr; Banerjee, Pushan; Das, Subrata

    2014-11-01

    In the present work attempts were made to synthesize indium doped CdS films by fabricating In/CdS bilayers using CBD-CdS on vacuum evaporated In thin films and subsequent air annealing. 135 nm CdS films were grown onto 20 nm and 35 nm indium coated glass substrate employing chemical bath deposition technique. The In/CdS bilayers thus formed were subjected to heat treatment at the temperatures between 200 and 400 °C for 4 min in the muffle furnace to facilitate indium to diffuse into the CdS films. XRD pattern ascertained no noticeable shift in lattice constant implying grain boundary metal segregation, while secondary ion mass spectrometry indicated the diffusion profile of indium into CdS matrices. Mass spectrometry results showed that substantial diffusion of indium had been taken place within CdS at 400 °C. Dark and photocurrent with different illumination time were measured to ascertain the photosensitivity of pure and composite CdS films.

  1. Oil sands development and its impact on atmospheric wet deposition of air pollutants to the Athabasca Oil Sands Region, Alberta, Canada.

    PubMed

    Lynam, Mary M; Dvonch, J Timothy; Barres, James A; Morishita, Masako; Legge, Allan; Percy, Kevin

    2015-11-01

    Characterization of air pollutant deposition resulting from Athabasca oil sands development is necessary to assess risk to humans and the environment. To investigate this we collected event-based wet deposition during a pilot study in 2010-2012 at the AMS 6 site 30 km from the nearest upgrading facility in Fort McMurray, AB, Canada. Sulfate, nitrate and ammonium deposition was (kg/ha) 1.96, 1.60 and 1.03, respectively. Trace element pollutant deposition ranged from 2 × 10(-5) - 0.79 and exhibited the trend Hg < Se < As < Cd < Pb < Cu < Zn < S. Crustal element deposition ranged from 1.4 × 10(-4) - 0.46 and had the trend: La < Ce < Sr < Mn < Al < Fe < Mg. S, Se and Hg demonstrated highest median enrichment factors (130-2020) suggesting emissions from oil sands development, urban activities and forest fires were deposited. High deposition of the elements Sr, Mn, Fe and Mg which are tracers for soil and crustal dust implies land-clearing, mining and hauling emissions greatly impacted surrounding human settlements and ecosystems.

  2. The Fall and Fall of Gary Hart.

    ERIC Educational Resources Information Center

    Rowland, Robert C.

    The fall of Gary Hart, brought about because of his indiscretions during the 1988 presidential campaign, should not be treated exclusively as a consequence of Hart's moral failings. Rather, the fall of Hart can be traced to a complex of factors including bad judgment, the near total control that the press exercises over the political agenda, and…

  3. Effect of biomass open burning on particulate matter and polycyclic aromatic hydrocarbon concentration levels and PAH dry deposition in ambient air.

    PubMed

    Chiu, Jui C; Shen, Yun H; Li, Hsing W; Chang, Shun S; Wang, Lin C; Chang-Chien, Guo P

    2011-01-01

    The objectives of the present study were to investigate particulate matter (PM) and polycyclic aromatic hydrocarbon (PAH) concentrations in ambient air during rice straw open burning and non-open burning periods. In the ambient air of a rice field, the mean PM concentration during and after an open burning event were 1828 and 102 μg m⁻³, respectively, which demonstrates that during a rice field open burning event, the PM concentration in the ambient air of rice field is over 17 times higher than that of the non-open burning period. During an open burning event, the mean total PAH and total toxic equivalence (BaP(eq)) concentrations in the ambient air of a rice field were 7206 ng m⁻³ and 10.3 ng m⁻³, respectively, whereas after the open burning event, they were 376 ng m⁻³ and 1.50 ng m⁻³, respectively. Open burning thus increases total PAH and total BaP(eq) concentrations by 19-fold and 6.8-fold, respectively. During a rice straw open burning event, in the ambient air of a rice field, the mean dry deposition fluxes of total PAHs and total BaP(eq) were 1222 μg m⁻² day⁻¹ and 4.80 μg m⁻² day⁻¹, respectively, which are approximately 60- and 3-fold higher than those during the non-open burning period, respectively. During the non-open burning period, particle-bound PAHs contributed 79.2-84.2% of total dry deposition fluxes (gas + particle) of total PAHs. However, an open burning event increases the contribution to total PAH dry deposition by particle-bound PAHs by up to 85.9-95.5%. The results show that due to the increased amount of PM in the ambient air resulting from rice straw open burning, particle-bound PAHs contributed more to dry deposition fluxes of total PAHs than they do during non-open burning periods. The results show that biomass (rice straw) open burning is an important PAH emission source that significantly increases both PM and PAH concentration levels and PAH dry deposition in ambient air.

  4. An accurate derivation of the air dose-rate and the deposition concentration distribution by aerial monitoring in a low level contaminated area

    NASA Astrophysics Data System (ADS)

    Nishizawa, Yukiyasu; Sugita, Takeshi; Sanada, Yukihisa; Torii, Tatsuo

    2015-04-01

    Since 2011, MEXT (Ministry of Education, Culture, Sports, Science and Technology, Japan) have been conducting aerial monitoring to investigate the distribution of radioactive cesium dispersed into the atmosphere after the accident at the Fukushima Dai-ichi Nuclear Power Plant (FDNPP), Tokyo Electric Power Company. Distribution maps of the air dose-rate at 1 m above the ground and the radioactive cesium deposition concentration on the ground are prepared using spectrum obtained by aerial monitoring. The radioactive cesium deposition is derived from its dose rate, which is calculated by excluding the dose rate of the background radiation due to natural radionuclides from the air dose-rate at 1 m above the ground. The first step of the current method of calculating the dose rate due to natural radionuclides is calculate the ratio of the total count rate of areas where no radioactive cesium is detected and the count rate of regions with energy levels of 1,400 keV or higher (BG-Index). Next, calculate the air dose rate of radioactive cesium by multiplying the BG-Index and the integrated count rate of 1,400 keV or higher for the area where the radioactive cesium is distributed. In high dose-rate areas, however, the count rate of the 1,365-keV peak of Cs-134, though small, is included in the integrated count rate of 1,400 keV or higher, which could cause an overestimation of the air dose rate of natural radionuclides. We developed a method for accurately evaluating the distribution maps of natural air dose-rate by excluding the effect of radioactive cesium, even in contaminated areas, and obtained the accurate air dose-rate map attributed the radioactive cesium deposition on the ground. Furthermore, the natural dose-rate distribution throughout Japan has been obtained by this method.

  5. Hydrologic and chemical data from selected wells and springs in southern Elmore County, including Mountain Home Air Force Base, southwestern Idaho, Fall 1989

    USGS Publications Warehouse

    Parliman, D.J.; Young, H.W.

    1990-01-01

    Hydrologic and chemical data were collected during September through November 1989 from 90 wells and 6 springs in southern Elmore County, southwestern Idaho. These data were collected to characterize the chemical quality of water in major water-yielding zones in areas near Mountain Home and the Mountain Home Air Force Base. The data include well and spring locations, well-construction and water-level information, and chemical analysis of water from each well and spring inventoried. Ground water in the study area is generally suitable for most uses. In localized areas, water is highly mineralized, and pH, concentrations of dissolved sulfate, chloride, or nitrite plus nitrate as nitrogen exceed national public drinking water limits. Fecal coliform and fecal streptococci bacteria were detected in separate water samples. One or more volatile organic compounds were detected in water samples from 15 wells, and the concentration of benzene exceeded the national public drinking water limit in a water sample from one well.

  6. Evaluation of fluorine release from air deposited coal spoil piles: A case study at Yangquan city, northern China.

    PubMed

    Gao, Xubo; Hu, Yandi; Li, Chengcheng; Dai, Chong; Li, Liang; Ou, Xiong; Wang, Yanxin

    2016-03-01

    The fluorine content of coal has been well documented, while such data of coal spoil are limited. In the present paper, fluorine in coal spoils and its releasing behavior were studied via leaching and combustion tests, as well as field investigation. Fluoride pollution in groundwater and soil occurred in the air depositing areas of coal spoils. The average content of fluorine in coal spoils was 525 mg/kg with the highest value of 1885 mg/kg. The only XRD detectable inorganic fluorine phase was fluorphlogopite. The absence of major fluorine bearing minerals in coal spoils suggested that bulk fluorine, rather than trace phases, resided in the mineral matrix. The major extracted species were water soluble fluorine and exchangeable fluorine in the coal spoils. Batch leaching tests illustrated that the leachable fluoride in coal spoils was widely distributed, ranging from 2.0 to 108.4 mg/kg. Column leaching tests showed a clear pH-dependent leaching behavior of fluorine: lower pH situation led to fluorine release from the mineral matrix; the loosely bound or easily exchangeable fluorine was also flushed out of the column. The higher ion strength or alkaline bicarbonate/carbonate rich leaching solution tended to free more fluorine into the acidic aqueous solution. The leachable fluorine in coal spoils was estimated as ca. 6%, based on the results of leaching tests. Also, our research found that over 90% of fluorine in coal spoils could be released into the atmosphere as a result of spontaneous combustion, accounting for over 40% of the total atmospheric fluorine emissions in northern China. Our investigation suggests that it is urgent to conduct comprehensive studies to assist the management and control of fluorine pollution at coal spoil banks. PMID:26734816

  7. Evaluation of fluorine release from air deposited coal spoil piles: A case study at Yangquan city, northern China.

    PubMed

    Gao, Xubo; Hu, Yandi; Li, Chengcheng; Dai, Chong; Li, Liang; Ou, Xiong; Wang, Yanxin

    2016-03-01

    The fluorine content of coal has been well documented, while such data of coal spoil are limited. In the present paper, fluorine in coal spoils and its releasing behavior were studied via leaching and combustion tests, as well as field investigation. Fluoride pollution in groundwater and soil occurred in the air depositing areas of coal spoils. The average content of fluorine in coal spoils was 525 mg/kg with the highest value of 1885 mg/kg. The only XRD detectable inorganic fluorine phase was fluorphlogopite. The absence of major fluorine bearing minerals in coal spoils suggested that bulk fluorine, rather than trace phases, resided in the mineral matrix. The major extracted species were water soluble fluorine and exchangeable fluorine in the coal spoils. Batch leaching tests illustrated that the leachable fluoride in coal spoils was widely distributed, ranging from 2.0 to 108.4 mg/kg. Column leaching tests showed a clear pH-dependent leaching behavior of fluorine: lower pH situation led to fluorine release from the mineral matrix; the loosely bound or easily exchangeable fluorine was also flushed out of the column. The higher ion strength or alkaline bicarbonate/carbonate rich leaching solution tended to free more fluorine into the acidic aqueous solution. The leachable fluorine in coal spoils was estimated as ca. 6%, based on the results of leaching tests. Also, our research found that over 90% of fluorine in coal spoils could be released into the atmosphere as a result of spontaneous combustion, accounting for over 40% of the total atmospheric fluorine emissions in northern China. Our investigation suggests that it is urgent to conduct comprehensive studies to assist the management and control of fluorine pollution at coal spoil banks.

  8. Using soil records with atmospheric dispersion modeling to investigate the effects of clean air regulations on 60 years of manganese deposition in Marietta, Ohio (USA).

    PubMed

    Carter, Megan R; Gaudet, Brian J; Stauffer, David R; White, Timothy S; Brantley, Susan L

    2015-05-15

    Atmospheric emissions of metals from anthropogenic activities have led to deposition and contamination of soils worldwide. We quantified addition of manganese (Mn) to soils around the largest emitter of Mn in the United States (U.S.) using chemical analyses and atmospheric dispersion modeling (Second-Order Closure Integrated Puff (SCIPUFF)). Concentrations of soil-surface Mn were enriched by 9-fold relative to that of the parent material within 1 km of the facility. Elevated concentrations of Mn and chromium (Cr), another potentially toxic element that was emitted, document contamination only within 1 m of the soil surface. Total mass of Mn added per unit land area integrated over 1 m, mMn, equals ~80 mg Mn cm(-2) near the facility. Values of mMn remained above background up to tens of kilometers from the source. Air concentrations of Mn particles of 7.5-micron diameter simulated with SCIPUFF using available data for the emission rate and local meteorological conditions for 2006 were consistent with measured air concentrations. However, the Mn deposition calculated for 2006 with SCIPUFF yielded a cumulative value over the lifetime of the refinery (60 years) that is a factor of 15 lower than the Mn observed to have been added to the soils. This discrepancy can be easily explained if Mn deposition rates before 1988 were more than an order of magnitude greater than today. Such higher emissions are probable, given the changes in metal production with time and the installation of emission controls after the Clean Air Act (1970). This work shows that atmospheric dispersion models can be used with soil profiles to understand the changes in metal emissions over decadal timescales. In addition, the calculations are consistent with the Clean Air Act accounting for a 15-fold decrease in the Mn deposition to soils around the refinery per metric ton of Mn alloy produced.

  9. Meteorite Falls in Morocco

    NASA Astrophysics Data System (ADS)

    Chennaoui Aoudjehane, H.

    2016-08-01

    The number of meteorite falls reported in Morocco since 2000 is highest than any other place compared to the other countries in the world, that call into question the efficiency of the randomly meteorite falls on Earth.

  10. Reconstructing the Chernobyl Nuclear Power Plant (CNPP) accident 30 years after. A unique database of air concentration and deposition measurements over Europe.

    PubMed

    Evangeliou, Nikolaos; Hamburger, Thomas; Talerko, Nikolai; Zibtsev, Sergey; Bondar, Yuri; Stohl, Andreas; Balkanski, Yves; Mousseau, Timothy A; Møller, Anders P

    2016-09-01

    30 years after the Chernobyl Nuclear Power Plant (CNPP) accident, its radioactive releases still remain of great interest mainly due to the long half-lives of many radionuclides emitted. Observations from the terrestrial environment, which hosts radionuclides for many years after initial deposition, are important for health and environmental assessments. Furthermore, such measurements are the basis for validation of atmospheric transport models and can be used for constraining the still not accurately known source terms. However, although the "Atlas of cesium deposition on Europe after the Chernobyl accident" (hereafter referred to as "Atlas") has been published since 1998, less than 1% of the direct observations of (137)Cs deposition has been made publicly available. The remaining ones are neither accessible nor traceable to specific data providers and a large fraction of these data might have been lost entirely. The present paper is an effort to rescue some of the data collected over the years following the CNPP accident and make them publicly available. The database includes surface air activity concentrations and deposition observations for (131)I, (134)Cs and (137)Cs measured and provided by Former Soviet Union authorities the years that followed the accident. Using the same interpolation tool as the official authorities, we have reconstructed a deposition map of (137)Cs based on about 3% of the data used to create the Atlas map. The reconstructed deposition map is very similar to the official one, but it has the advantage that it is based exclusively on documented data sources, which are all made available within this publication. In contrast to the official map, our deposition map is therefore reproducible and all underlying data can be used also for other purposes. The efficacy of the database was proved using simulated activity concentrations and deposition of (137)Cs from a Langrangian and a Euleurian transport model. PMID:27376994

  11. Reconstructing the Chernobyl Nuclear Power Plant (CNPP) accident 30 years after. A unique database of air concentration and deposition measurements over Europe.

    PubMed

    Evangeliou, Nikolaos; Hamburger, Thomas; Talerko, Nikolai; Zibtsev, Sergey; Bondar, Yuri; Stohl, Andreas; Balkanski, Yves; Mousseau, Timothy A; Møller, Anders P

    2016-09-01

    30 years after the Chernobyl Nuclear Power Plant (CNPP) accident, its radioactive releases still remain of great interest mainly due to the long half-lives of many radionuclides emitted. Observations from the terrestrial environment, which hosts radionuclides for many years after initial deposition, are important for health and environmental assessments. Furthermore, such measurements are the basis for validation of atmospheric transport models and can be used for constraining the still not accurately known source terms. However, although the "Atlas of cesium deposition on Europe after the Chernobyl accident" (hereafter referred to as "Atlas") has been published since 1998, less than 1% of the direct observations of (137)Cs deposition has been made publicly available. The remaining ones are neither accessible nor traceable to specific data providers and a large fraction of these data might have been lost entirely. The present paper is an effort to rescue some of the data collected over the years following the CNPP accident and make them publicly available. The database includes surface air activity concentrations and deposition observations for (131)I, (134)Cs and (137)Cs measured and provided by Former Soviet Union authorities the years that followed the accident. Using the same interpolation tool as the official authorities, we have reconstructed a deposition map of (137)Cs based on about 3% of the data used to create the Atlas map. The reconstructed deposition map is very similar to the official one, but it has the advantage that it is based exclusively on documented data sources, which are all made available within this publication. In contrast to the official map, our deposition map is therefore reproducible and all underlying data can be used also for other purposes. The efficacy of the database was proved using simulated activity concentrations and deposition of (137)Cs from a Langrangian and a Euleurian transport model.

  12. Chemical composition of tropospheric air masses encountered during high altitude flights (>11.5 km) during the 2009 fall Operation Ice Bridge field campaign

    NASA Astrophysics Data System (ADS)

    Yang, Mei Ying Melissa; Vay, Stephanie A.; Stohl, Andreas; Choi, Yonghoon; Diskin, Glenn S.; Sachse, Glen W.; Blake, Donald R.

    2012-09-01

    As part of the 2009 Operation Ice Bridge campaign, the NASA DC-8 aircraft was used to fill the data-time gap in laser observation of the changes in ice sheets, glaciers and sea ice between ICESat-I (Ice, Cloud, and land Elevation Satellite) and ICESat-II. Complementing the cryospheric instrument payload were four in situ atmospheric sampling instruments integrated onboard to measure trace gas concentrations of CO2, CO, N2O, CH4, water vapor and various VOCs (Volatile Organic Compounds). This paper examines two plumes encountered at high altitude (12 km) during the campaign; one during a southbound transit flight (13°S) and the other at 86°S over Antarctica. The data presented are especially significant as the Southern Hemisphere is heavily under-sampled during the austral spring, with few if any high-resolution airborne observations of atmospheric gases made over Antarctica. Strong enhancements of CO, CH4, N2O, CHCl3, OCS, C2H6, C2H2 and C3H8 were observed in the two intercepted air masses that exhibited variations in VOC composition suggesting different sources. The transport model FLEXPART showed that the 13°S plume contained predominately biomass burning emissions originating from Southeast Asia and South Africa, while both anthropogenic and biomass burning emissions were observed at 86°S with South America and South Africa as indicated source regions. The data presented here show evidence that boundary layer pollution is transported from lower latitudes toward the upper troposphere above the South Pole, which may not have been observed in the past.

  13. Atmospheric Mercury Concentrations Near Salmon Falls Creek Reservoir - Phase 1

    SciTech Connect

    M. L. Abbott

    2005-10-01

    Elemental and reactive gaseous mercury (EGM/RGM) were measured in ambient air concentrations over a two-week period in July/August 2005 near Salmon Falls Creek Reservoir, a popular fishery located 50 km southwest of Twin Falls, Idaho. A fish consumption advisory for mercury was posted at the reservoir in 2002 by the Idaho Department of Health and Welfare. The air measurements were part of a multi-media (water, sediment, precipitation, air) study initiated by the Idaho Department of Environmental Quality and the U.S. Environmental Protection Agency (EPA) Region 10 to identify potential sources of mercury contamination to the reservoir. The sampling site is located about 150 km northeast of large gold mining operations in Nevada, which are known to emit large amounts of mercury to the atmosphere (est. 2,200 kg/y from EPA 2003 Toxic Release Inventory). The work was co-funded by the Idaho National Laboratory’s Community Assistance Program and has a secondary objective to better understand mercury inputs to the environment near the INL, which lies approximately 230 km to the northeast. Sampling results showed that both EGM and RGM concentrations were significantly elevated (~ 30 – 70%, P<0.05) compared to known regional background concentrations. Elevated short-term RGM concentrations (the primary form that deposits) were likely due to atmospheric oxidation of high EGM concentrations, which suggests that EGM loading from upwind sources could increase Hg deposition in the area. Back-trajectory analyses indicated that elevated EGM and RGM occurred when air parcels came out of north-central and northeastern Nevada. One EGM peak occurred when the air parcels came out of northwestern Utah. Background concentrations occurred when the air was from upwind locations in Idaho (both northwest and northeast). Based on 2003 EPA Toxic Release Inventory data, it is likely that most of the observed peaks were from Nevada gold mine sources. Emissions from known large natural mercury

  14. Air pollution and changes in forest nitrogen status: Fog and rain deposition and nitrogen losses from forested watersheds in the San Bernardino Mountains. Final report

    SciTech Connect

    Fenn, M.E.; Poth, M.A.

    1998-08-01

    The primary objective of this project was to examine the effects of N deposition on mixed conifer forests in southern California. Studies were conducted at selected sites an air pollution gradient in the San Bernardino Mountains (SBM). The main tasks were: (1) to measure N deposition to the forest in fog and throughfall, (2) to determine spatial and temporal patterns of nitrate export in stream water, and (3) to quantify trace gas fluxes from soil at sites with high and low N deposition. Fog was found to be an important N source at the western end of the SMB due to his high frequency and presence at elevated concentrations. N deposition from throughfall was found to be similar to levels in forests where adverse effects have occurred. Annual fluxes of N from soil were 18-times higher at the western end of the SBM than at the eastern end. The data provide evidence of forest nitrogen saturation caused by the deposition of anthropogenic pollutants over a multi-decade period in the SBM.

  15. Landscapes, depositional environments and human occupation at Middle Paleolithic open-air sites in the southern Levant, with new insights from Nesher Ramla, Israel

    NASA Astrophysics Data System (ADS)

    Zaidner, Yossi; Frumkin, Amos; Friesem, David; Tsatskin, Alexander; Shahack-Gross, Ruth

    2016-04-01

    Middle Paleolithic human occupation in the Levant (250-50 ka ago) has been recorded in roofed (cave and rockshelter) and open-air sites. Research at these different types of sites yielded different perspectives on the Middle Paleolithic human behavior and evolution. Until recently, open-air Middle Paleolithic sites in the Levant were found in three major sedimentary environments: fluvial, lake-margin and spring. Here we describe a unique depositional environment and formation processes at the recently discovered open-air site of Nesher Ramla (Israel) and discuss their contribution to understanding site formation processes in open-air sites in the Levant. The site is 8-m-thick Middle Paleolithic sequence (OSL dated to 170-80 ka) that is located in a karst sinkhole formed by gravitational deformation and sagging into underground voids. The sedimentary sequence was shaped by gravitational collapse, cyclic colluviation of soil and gravel into the depression, waterlogging, in situ pedogenesis and human occupation. Original bedding and combustion features are well-preserved in the Lower archaeological sequence, a rare occurrence in comparison to other open-air archaeological sites. This phenomenon coincides with episodes of fast sedimentation/burial, which also allowed better preservation of microscopic remains such as ash. The Upper archaeological sequence does not exhibit bedding or preservation of ash, despite presence of heat-affected lithic artifacts, which makes it similar to other open-air sites in the Levant. We suggest that rate of burial is the major factor that caused the difference between the Upper and Lower sequences. The differences in the burial rate may be connected to environmental and vegetation changes at the end of MIS 6. We also identified an interplay between sediment in-wash and density of human activity remains, i.e. during episodes of low natural sediment input the density of artifacts is higher relative to episodes with high rate of sediment in

  16. Influence of dust loading on the alpha-particle energy resolution of continuous air monitors for thin deposits of radioactive aerosols.

    PubMed

    Huang, Suilou; Schery, Stephen D; Alcantara, Raul E; Rodgers, John C; Wasiolek, Piotr T

    2002-12-01

    Alpha-particle continuous air monitors must sometimes be operated in dusty environments where significant dust loading of the filter can be anticipated. It is important to understand how this dust loading affects the response of the continuous air monitors. Not only must a filter be changed if there is a reduction in airflow, but a change may be necessary if the energy resolution deteriorates and the continuous air monitor loses sensitivity and specificity for the radioactive aerosols of interest. A series of experiments were conducted to investigate alpha-particle energy resolution of continuous air monitor filters, particularly under dust loading conditions. Aerosol particles of various sizes were tagged with radon decay products to serve as surrogates for radioactive aerosols of interest such as plutonium or uranium. While the size of radioactive aerosols, filter type, and dust type affected the energy resolution, the thickness of an underlying (nonradioactive) dust layer did not show significant effect for the materials studied and a loading range of 0.01-10 mg x cm(-2). Our results indicate that it is possible for continuous air monitors to detect the release of radioactive aerosols with little deterioration in energy resolution under conditions of significant dust loading provided that the deposited layer of radioactive aerosols remains thin (< or = 0.1 mg x cm(-2)).

  17. Gold Veins near Great Falls, Maryland

    USGS Publications Warehouse

    Reed, John Calvin, Jr.; Reed, John C.

    1969-01-01

    Small deposits of native gold are present along an anastomosing system of quartz veins and shear zones just east of Great Falls, Montgomery County, Md. The deposits were discovered in 1861 and were worked sporadically until 1951, yielding more than 5,000 ounces of gold. The vein system and the principal veins within it strike a few degrees west of north, at an appreciable angle to foliation and fold axial planes in enclosing rocks of the Wissahickon Formation of late Precambrian (?) age. The veins cut granitic rocks of Devonian or pre-Devonian age and may be as young as Triassic. Further development of the deposits is unlikely under present economic conditions because of their generally low gold content and because much of the vein system lies on park property, but study of the Great Falls vein system may be useful in the search for similar deposits elsewhere in the Appalachian Piedmont.

  18. ESTIMATES OF THE ATMOSPHERIC DEPOSITION OF SULFUR AND NITROGEN SPECIES: CLEAN AIR STATUS AND TRENDS NETWORK. 1990 THROUGH 2000

    EPA Science Inventory

    The Clean Air Status and Trends Network (CASTNet) was established by EPA in response to the requirements of the 1990 Clean Air Act Amendments. To satisfy these requirements CASTNet was designed to assess and report on geographic patterns and long-term, temporal trends in ambient ...

  19. Fall Enrollment Report 2009

    ERIC Educational Resources Information Center

    Iowa Department of Education, 2009

    2009-01-01

    This report summarizes fall enrollment in Iowa's community colleges. Every year Iowa's 15 community college districts submit data on students enrolled on the 10th day of the fall semester. Highlights include: (1) Enrollment grew at its fastest pace since 1975 to a record high of 100,736 students; (2) Year-to-year growth was 14.3 percent, which is…

  20. Experiments in Free Fall

    ERIC Educational Resources Information Center

    Art, Albert

    2006-01-01

    A model lift containing a figure of Albert Einstein is released from the side of a tall building and its free fall is arrested by elastic ropes. This arrangement allows four simple experiments to be conducted in the lift to demonstrate the effects of free fall and show how they can lead to the concept of the equivalence of inertial and…

  1. Learning From Falling

    ERIC Educational Resources Information Center

    Joh, Amy, S.; Adolph, Karen, E.

    2006-01-01

    Walkers fall frequently, especially during infancy. Children (15, 21, 27, 33, and 39 month-olds) and adults were tested in a novel foam pit paradigm to examine age-related changes in the relationship between falling and prospective control of locomotion. In trial 1, participants walked and fell into a deformable foam pit marked with distinct…

  2. First Aid: Falls

    MedlinePlus

    ... Story" 5 Things to Know About Zika & Pregnancy First Aid: Falls KidsHealth > For Parents > First Aid: Falls Print A A A Text Size en ... Floors, Doors & Windows, Furniture, Stairways: Household Safety Checklist First Aid: Broken Bones Head Injuries Preventing Children's Sports Injuries ...

  3. Fall Leaf Portraits

    ERIC Educational Resources Information Center

    O'Hara, Cristina

    2012-01-01

    In this article, the author describes how students can create a stunning as well as economical mosaic utilizing fall's brilliantly colored leaves, preserved at their peak in color. Start by choosing a beautiful fall day to take students on a nature walk to collect a variety of leaves in different shapes, sizes, and colors. Focus on collecting a…

  4. Fall prevention conceptual framework.

    PubMed

    Abraham, Sam

    2011-01-01

    Falls can have lasting psychological and physical consequences, particularly fractures and slow-healing processes, and patients may also lose confidence in walking. Injuries from falls lead to functional decline, institutionalization, higher health care costs, and decreased quality of life. The process related to the problem of patient falls in the hospital, using the nursing model developed by the theorist, Ida Jean Orlando, is explained in this article. The useful tool that provides guidance to marketers in this endeavor is Maslow's hierarchy of needs. During acute illness, individuals are greatly in need of satisfying their physiological needs. If these needs are not met, patients leave the hospital lacking a positive experience. Initial fall risk assessment is critical to plan intervention and individualize care plan. Interventions depend on the severity of fall risk factors.

  5. Pre-impact fall detection.

    PubMed

    Hu, Xinyao; Qu, Xingda

    2016-06-01

    Pre-impact fall detection has been proposed to be an effective fall prevention strategy. In particular, it can help activate on-demand fall injury prevention systems (e.g. inflatable hip protectors) prior to fall impacts, and thus directly prevent the fall-related physical injuries. This paper gave a systematical review on pre-impact fall detection, and focused on the following aspects of the existing pre-impact fall detection research: fall detection apparatus, fall detection indicators, fall detection algorithms, and types of falls for fall detection evaluation. In addition, the performance of the existing pre-impact fall detection solutions were also reviewed and reported in terms of their sensitivity, specificity, and detection/lead time. This review also summarized the limitations in the existing pre-impact fall detection research, and proposed future research directions in this field.

  6. Pre-impact fall detection.

    PubMed

    Hu, Xinyao; Qu, Xingda

    2016-01-01

    Pre-impact fall detection has been proposed to be an effective fall prevention strategy. In particular, it can help activate on-demand fall injury prevention systems (e.g. inflatable hip protectors) prior to fall impacts, and thus directly prevent the fall-related physical injuries. This paper gave a systematical review on pre-impact fall detection, and focused on the following aspects of the existing pre-impact fall detection research: fall detection apparatus, fall detection indicators, fall detection algorithms, and types of falls for fall detection evaluation. In addition, the performance of the existing pre-impact fall detection solutions were also reviewed and reported in terms of their sensitivity, specificity, and detection/lead time. This review also summarized the limitations in the existing pre-impact fall detection research, and proposed future research directions in this field. PMID:27251528

  7. Atmospheric Mercury near Salmon Falls Creek Reservoir in Southern Idaho

    SciTech Connect

    Michael L. Abbott; Jeffrey J. Einerson

    2007-12-01

    Gaseous elemental mercury (GEM) and reactive gaseous mercury (RGM) were measured over two-week seasonal field campaigns near Salmon Falls Creek Reservoir in south-central Idaho from the summer of 2005 through the fall of 2006 and over the entire summer of 2006 using automated Tekran mercury analyzers. GEM, RGM, and particulate mercury (HgP) were also measured at a secondary site 90 km to the west in southwestern Idaho during the summer of 2006. The study was performed to characterize mercury air concentrations in the southern Idaho area for the first time, estimate mercury dry deposition rates, and investigate the source of observed elevated concentrations. High seasonal variability was observed with the highest GEM (1.91 ± 0.9 ng m-3) and RGM (8.1 ± 5.6 pg m-3) concentrations occurring in the summer and lower values in the winter (1.32 ± 0.3 ng m-3, 3.2 ± 2.9 pg m-3 for GEM, RGM respectively). The summer-average HgP concentrations were generally below detection limit (0.6 ± 1 pg m-3). Seasonally-averaged deposition velocities calculated using a resistance model were 0.034 ± 0.032, 0.043 ± 0.040, 0.00084 ± 0.0017 and 0.00036 ± 0.0011 cm s-1 for GEM (spring, summer, fall, and winter, respectively) and 0.50 ± 0.39, 0.40 ± 0.31, 0.51 ± 0.43 and 0.76 ± 0.57 cm s-1 for RGM. The total annual RGM + GEM dry deposition estimate was calculated to be 11.9 ± 3.3 µg m-2, or about 2/3 of the total (wet + dry) deposition estimate for the area. Periodic elevated short-term GEM (2.2 – 12 ng m-3) and RGM (50 - 150 pg m-3) events were observed primarily during the warm seasons. Back-trajectory modeling and PSCF analysis indicated predominant source directions from the southeast (western Utah, northeastern Nevada) through the southwest (north-central Nevada) with fewer inputs from the northwest (southeastern Oregon and southwestern Idaho).

  8. Supercapacitor electrode based on mixtures of graphene/graphite and carbon nanotubes fabricated using a new dynamic air-brush deposition technique

    NASA Astrophysics Data System (ADS)

    Bondavalli, P.; Delfaure, C.; Pribat, D.; Legagneux, P.

    2013-09-01

    This contribution deals with the fabrication of electrode and supercapacitor cell using a new dynamic air-brush deposition technique. This method allows to achieve extremely (ou highly) uniform mats with finely tuned thickness and weight in a completely reproducible way. Using this deposition technique, we have analyzed the effect of mixture of CNTs and graphene/graphite on the electrode and cell properties (energy, power and capacitance). using a mixture of 75% of graphene/graphite and 25% of CNTs we increased the power by a factor 2.5 compared to bare CNTs based electrodes. We also analyzed the effect of the weight firstly on the capacitance and specific energy and then on the specific power. We were able to reach a specific power of 200kW/Kg and a specific energy of 9.1Wh/Kg with an electrode having a surface of 2cm2 and a weight of 0.25mg composed by 50% of CNTs and graphene/graphite (using a common aqueous electrolyte). using our deposition technique we are able to achieve supercapacitors with ad-hoc characteristics simply modulating the weight and the concentration of the mixture in a completely reproducible way.

  9. Cellular response to the deposition of diesel exhaust particle aerosols onto human lung cells grown at the air-liquid interface by inertial impaction.

    PubMed

    Cooney, Daniel J; Hickey, Anthony J

    2011-12-01

    The pathogenesis of disease resulting from exposure to diesel exhaust particles (DEP) is often studied using cultured lung cells. Frequently, researchers expose cells to DEP by spiking a suspension of particles in liquid onto the apical surface. This is not representative of in vivo exposure, where aerosols are deposited onto cell surfaces at the air-liquid interface (ALI). Inertial impaction provides an opportunity to deliver high doses of particles with aerodynamic diameters>∼1 μm to the surface of cells in seconds in a reproducible and predictable manner. A custom device was constructed to deposit DEP aerosols onto the surface of Calu-3 and A549 cells grown at the ALI. The pro-inflammatory and toxic cellular response to exposure to the deposited DEP aerosols was measured and compared to the response of cells exposed to DEP as suspensions. Calu-3 cells showed evidence of an oxidative stress response for both exposure types, while there was strong evidence to suggest that the method of aerosol delivery was harmful to the A549 cells.

  10. Microstructure studies of air-plasma-spray-deposited CoNiCrAlY coatings before and after thermal cyclic loading for high-temperature application

    NASA Astrophysics Data System (ADS)

    Kumar, Dipak; Pandey, K. N.; Das, Dipak Kumar

    2016-08-01

    In the present study, bond-coats for thermal barrier coatings were deposited via air plasma spraying (APS) techniques onto Inconel 800 and Hastelloy C-276 alloy substrates. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and atomic force microscopy (AFM) were used to investigate the phases and microstructure of the as-sprayed, APS-deposited CoNiCrAlY bond-coatings. The aim of this work was to study the suitability of the bond-coat materials for high temperature applications. Confirmation of nanoscale grains of the γ/γ'-phase was obtained by TEM, high-resolution TEM, and AFM. We concluded that these changes result from the plastic deformation of the bond-coat during the deposition, resulting in CoNiCrAlY bond-coatings with excellent thermal cyclic resistance suitable for use in high-temperature applications. Cyclic oxidative stability was observed to also depend on the underlying metallic alloy substrate.

  11. Seneca Falls. Classroom Focus.

    ERIC Educational Resources Information Center

    Balantic, Jeannette; Libresco, Andrea S.

    1995-01-01

    Presents a secondary school lesson based on the Seneca Falls Declaration of Sentiments. Provides lesson objectives and step-by-step instructional procedures. Includes quoted sections of the Declaration of Sentiments. (CFR)

  12. Editors' Fall Picks

    ERIC Educational Resources Information Center

    Hoffert, Barbara; Heilbrun, Margaret; Kuzyk, Raya; Kim, Ann; McCormack, Heather; Katterjohn, Anna; Burns, Ann; Williams, Wilda

    2008-01-01

    From the fall's cascade of great new books, "Library Journal's" editors select their favorites--a dark rendition of Afghan life, a look at the "self-esteem trap," a celebration of Brooklyn activism, and much more.

  13. Survival of falling robots

    NASA Astrophysics Data System (ADS)

    Cameron, Jonathan M.; Arkin, Ronald C.

    1992-02-01

    As mobile robots are used in more uncertain and dangerous environments, it will become important to design them so that they can survive falls. In this paper, we examine a number of mechanisms and strategies that animals use to withstand these potentially catastrophic events and extend them to the design of robots. A brief survey of several aspects of how common cats survive falls provides an understanding of the issues involved in preventing traumatic injury during a falling event. After outlining situations in which robots might fall, a number of factors affecting their survival are described. From this background, several robot design guidelines are derived. These include recommendations for the physical structure of the robot as well as requirements for the robot control architecture. A control architecture is proposed based on reactive control techniques and action-oriented perception that is geared to support this form of survival behavior.

  14. Survival of falling robots

    NASA Technical Reports Server (NTRS)

    Cameron, Jonathan M.; Arkin, Ronald C.

    1992-01-01

    As mobile robots are used in more uncertain and dangerous environments, it will become important to design them so that they can survive falls. In this paper, we examine a number of mechanisms and strategies that animals use to withstand these potentially catastrophic events and extend them to the design of robots. A brief survey of several aspects of how common cats survive falls provides an understanding of the issues involved in preventing traumatic injury during a falling event. After outlining situations in which robots might fall, a number of factors affecting their survival are described. From this background, several robot design guidelines are derived. These include recommendations for the physical structure of the robot as well as requirements for the robot control architecture. A control architecture is proposed based on reactive control techniques and action-oriented perception that is geared to support this form of survival behavior.

  15. 6. NARADA FALLS, WITH FIRST CROSSING BRIDGE SHOWN ABOVE FALLS, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. NARADA FALLS, WITH FIRST CROSSING BRIDGE SHOWN ABOVE FALLS, VIEW FACING NORTHEAST - Paradise River First Crossing Bridge, Spanning Paradise River at Narada Falls on Service Road, Longmire, Pierce County, WA

  16. Air concentrations and wet deposition of major inorganic ions at five non-urban sites in China, 2001-2003

    NASA Astrophysics Data System (ADS)

    Aas, Wenche; Shao, Min; Jin, Lei; Larssen, Thorjørn; Zhao, Dawei; Xiang, Renjun; Zhang, Jinhong; Xiao, Jinsong; Duan, Lei

    Air and precipitation measurements at five sites were undertaken from 2001 to 2003 in four different provinces in China, as part of the acid rain monitoring program IMPACTS. The sites were located in Tie Shan Ping (TSP) in Chongqing, Cai Jia Tang (CJT) in Hunan, Lei Gong Shan (LGS) and Liu Chong Guan (LCG) in Guizhou and Li Xi He (LXH) in Guangdong. The site characteristics are quite varied with TSP and LCG located relatively near big cites while the three others are situated in more regionally representative areas. The distances to urban centres are reflected in the air pollution concentrations, with annual average concentrations of SO 2 ranging from 0.5 to above 40 μg S m -3. The main components in the airborne particles are (NH 4) 2SO 4 and CaSO 4. Reduced nitrogen has a considerably higher concentration level than oxidised nitrogen, reflecting the high ammonia emissions from agriculture. The gas/particle ratio for the nitrogen compounds is about 1:1 at all the three intensive measurement sites, while for sulphur it varies from 2.5 to 0.5 depending on the distance to the emission sources. As in air, the predominant ions in precipitation are sulphate, calcium and ammonium. The volume weighted annual concentration of sulphate ranges from about 70 μeq l -1 at the most rural site (LGS) to about 200 μeq l -1 at TSP and LCG. The calcium concentration ranges from 25 to 250 μeq l -1, while the total nitrogen concentration is between 30 and 150 μeq l -1; ammonium is generally twice as high as nitrate. China's acid rain research has traditionally been focused on urban sites, but these measurements show a significant influence of long range transported air pollutants to rural areas in China. The concentration levels are significantly higher than seen in most other parts of the world.

  17. Features of air masses associated with the deposition of Pseudomonas syringae and Botrytis cinerea by rain and snowfall.

    PubMed

    Monteil, Caroline L; Bardin, Marc; Morris, Cindy E

    2014-11-01

    Clarifying the role of precipitation in microbial dissemination is essential for elucidating the processes involved in disease emergence and spread. The ecology of Pseudomonas syringae and its presence throughout the water cycle makes it an excellent model to address this issue. In this study, 90 samples of freshly fallen rain and snow collected from 2005-2011 in France were analyzed for microbiological composition. The conditions favorable for dissemination of P. syringae by this precipitation were investigated by (i) estimating the physical properties and backward trajectories of the air masses associated with each precipitation event and by (ii) characterizing precipitation chemistry, and genetic and phenotypic structures of populations. A parallel study with the fungus Botrytis cinerea was also performed for comparison. Results showed that (i) the relationship of P. syringae to precipitation as a dissemination vector is not the same for snowfall and rainfall, whereas it is the same for B. cinerea and (ii) the occurrence of P. syringae in precipitation can be linked to electrical conductivity and pH of water, the trajectory of the air mass associated with the precipitation and certain physical conditions of the air mass (i.e. temperature, solar radiation exposure, distance traveled), whereas these predictions are different for B. cinerea. These results are pertinent to understanding microbial survival, emission sources and atmospheric processes and how they influence microbial dissemination.

  18. Features of air masses associated with the deposition of Pseudomonas syringae and Botrytis cinerea by rain and snowfall

    PubMed Central

    Monteil, Caroline L; Bardin, Marc; Morris, Cindy E

    2014-01-01

    Clarifying the role of precipitation in microbial dissemination is essential for elucidating the processes involved in disease emergence and spread. The ecology of Pseudomonas syringae and its presence throughout the water cycle makes it an excellent model to address this issue. In this study, 90 samples of freshly fallen rain and snow collected from 2005–2011 in France were analyzed for microbiological composition. The conditions favorable for dissemination of P. syringae by this precipitation were investigated by (i) estimating the physical properties and backward trajectories of the air masses associated with each precipitation event and by (ii) characterizing precipitation chemistry, and genetic and phenotypic structures of populations. A parallel study with the fungus Botrytis cinerea was also performed for comparison. Results showed that (i) the relationship of P. syringae to precipitation as a dissemination vector is not the same for snowfall and rainfall, whereas it is the same for B. cinerea and (ii) the occurrence of P. syringae in precipitation can be linked to electrical conductivity and pH of water, the trajectory of the air mass associated with the precipitation and certain physical conditions of the air mass (i.e. temperature, solar radiation exposure, distance traveled), whereas these predictions are different for B. cinerea. These results are pertinent to understanding microbial survival, emission sources and atmospheric processes and how they influence microbial dissemination. PMID:24722630

  19. Free fall of a cat—freshman physics exercise

    NASA Astrophysics Data System (ADS)

    Studnička, Filip; Šlégr, Jan; Štegner, David

    2016-07-01

    This paper describes theoretical calculation of the terminal velocity of falling cat, taking the air drag into account. The results show that a fall from the seventh floor is critical for the cat so we introduce a new quantity called the ‘coefficient of the cat’s fear’ during free fall. A subsequent experiment with a model of a cat carrying the accelerometer confirmed this conclusion. This calculation and experiment can act as a strong motivational factor during introductory physics courses.

  20. Efficient, air-stable colloidal quantum dot solar cells encapsulated using atomic layer deposition of a nanolaminate barrier

    SciTech Connect

    Ip, Alexander H.; Labelle, André J.; Sargent, Edward H.

    2013-12-23

    Atomic layer deposition was used to encapsulate colloidal quantum dot solar cells. A nanolaminate layer consisting of alternating alumina and zirconia films provided a robust gas permeation barrier which prevented device performance degradation over a period of multiple weeks. Unencapsulated cells stored in ambient and nitrogen environments demonstrated significant performance losses over the same period. The encapsulated cell also exhibited stable performance under constant simulated solar illumination without filtration of harsh ultraviolet photons. This monolithically integrated thin film encapsulation method is promising for roll-to-roll processed high efficiency nanocrystal solar cells.

  1. A chemical deposition method to prepare circular planar 147Pm sources for the measurement of particulate emission in air.

    PubMed

    Udhayakumar, J; Gandhi, Shyamala S; Kumar, Manoj; Dash, Ashutosh

    2013-09-01

    This paper describes a method for preparing a circular planar source of 17 mm diameter containing approximately 400 kBq of (147)Pm employing a wet chemical deposition technique to be used in dust monitors. This manuscript described the overall process concept and experimental procedure. The technical feasibility, efficiency of the process and product quality has been evaluated. The quality of the prepared source in terms of nonleachability, uniform distribution of activity and stability, which are necessary attributes of a radioactive source were evaluated and found to be satisfactory.

  2. Terminal Velocity of a Shuttlecock in Vertical Fall.

    ERIC Educational Resources Information Center

    Peastrel, Mark; And Others

    1980-01-01

    Describes a straightforward vertical fall experiment using a badminton shuttlecock, a tape measure, and a millisecond timer. The effects of air resistance are important and directly measurable. The experimental data best fit a predictive model which assumes a resistive force quadratic in the instantaneous speed of the falling object. (GS)

  3. Paediatric bed fall computer simulation model development and validation.

    PubMed

    Thompson, Angela K; Bertocci, Gina E

    2013-01-01

    Falls from beds and other household furniture are common scenarios stated to conceal child abuse. Knowledge of the biomechanics associated with short-distance falls may aid clinicians in distinguishing between abusive and accidental injuries. Computer simulation is a useful tool to investigate injury-producing events and to study the effect of altering event parameters on injury risk. In this study, a paediatric bed fall computer simulation model was developed and validated. The simulation was created using Mathematical Dynamic Modeling(®) software with a child restraint air bag interaction (CRABI) 12-month-old anthropomorphic test device (ATD) representing the fall victim. The model was validated using data from physical fall experiments of the same scenario with an instrumented CRABI ATD. Validation was conducted using both observational and statistical comparisons. Future parametric sensitivity studies using this model will lead to an improved understanding of relationships between child (fall victim) parameters, fall environment parameters and injury potential.

  4. Source apportionment of polycyclic aromatic hydrocarbon wet and dry deposition at Massachusetts Bay

    NASA Astrophysics Data System (ADS)

    Fisher, George F.

    2001-07-01

    Polycyclic aromatic hydrocarbons (PAHs) result from incomplete combustion of fossil fuels and biomass. They are toxic, mutagenic and carcinogenic. PAHs are transported by winds until they are deposited on land or water or are chemically degraded. Wet deposition occurs when PAHs deposit during precipitation. Dry deposition occurs through direct impingment with the surface or through gas-exchange. An improved, computer controlled deposition collector was designed and developed to specifically collect PAH deposition. Wet deposition falls directly into a funnel while dry deposition is collected on a water surface, simulating deposition onto the ocean. Both samples drain quickly into a sample bottle which prevents sample volatilization and loss. Collected samples were analyzed with a gas chromatograph mass spectrometer (GC/MS). Analysis of backward air parcel trajectories showed the highest wet deposition was associated with trajectories through the northeast urban industrial corridor between Washington, DC and Boston, MA. The degree of industrialization and population along the trajectory route and exposure time affected wet deposition amounts. Dry deposition samples were analyzed using wind roses and local area trajectories. Deposition rates were related to the wind climatology with highest deposition associated with winds from the concentrated commercial and population areas west of the collection site. Increased deposition associated with easterly sectors indicate aircraft operations in those directions may contribute significantly to dry deposition. Deposition roses apportion 26% southeast, 22.9% west, 20.5% northwest, 17.9% north, 8.5% southwest and 4.2% northeast. Trajectory analysis showed that longer exposure times produced higher deposition rates. Both wet and dry deposition showed seasonal trends. Winter recorded the highest deposition due to increased fuel combustion for heating and lower mixing depths. The ability to collect dry deposition only when the

  5. A Variable Trajectory Plume Segment Model to Assess Ground-Level Air Concentrations and Depositions of Routine Effluent Releases from Nuclear Power Facilities.

    1986-05-27

    Version: 00 MESODIF-II, which embodies a variable trajectory plume segment atmospheric transport model, is designed to predict normalized air concentrations and deposition of radioactive, but otherwise non-reactive, effluents released from one or two levels over the same position in an xy-plane. In such a model, calculated particle trajectories vary as synoptic scale wind varies. At all sampling times, the particles are connected to form a segmented plume centerline. The lateral and vertical dimensions of themore » plume are determined by a parameterization of turbulence scale diffusion. The impetus for the development of this model arose from the need of the U. S. Nuclear Regulatory Commission to assess radiological effects resulting from routine nuclear power reactor operations, as outlined in U. S. Nuclear Regulatory Guide 1.111.« less

  6. Uniform, stable, and efficient planar-heterojunction perovskite solar cells by facile low-pressure chemical vapor deposition under fully open-air conditions.

    PubMed

    Luo, Paifeng; Liu, Zhaofan; Xia, Wei; Yuan, Chenchen; Cheng, Jigui; Lu, Yingwei

    2015-02-01

    Recently, hybrid perovskite solar cells (PSCs) have attracted extensive attention due to their high efficiency and simple preparing process. Herein, a facile low-pressure chemical vapor deposition (LPCVD) technology is first developed to fabricate PSCs, which can effectively reduce the over-rapid intercalating reaction rate and easily overcome this blocking issue during the solution process. As a result, the prepared uniform perovskite films exhibit good crystallization, strong absorption, and long carrier diffusion length. More strikingly, CH3NH3PbI3 absorbers by LPCVD demonstrate excellent moisture-resistant feature even under laser illumination and high-temperature conditions, which indicates that our proprietary method is very suitable for the future low-cost, nonvacuum production of the new generation photovoltaic devices. Finally, high efficiency of 12.73% is successfully achieved under fully open-air conditions. To the best of our knowledge, this is the first report of efficient PSCs with such a high humidity above 60%.

  7. A Variable Trajectory Plume Segment Model to Assess Ground-Level Air Concentrations and Depositions of Routine Effluent Releases from Nuclear Power Facilities.

    SciTech Connect

    1986-05-27

    Version: 00 MESODIF-II, which embodies a variable trajectory plume segment atmospheric transport model, is designed to predict normalized air concentrations and deposition of radioactive, but otherwise non-reactive, effluents released from one or two levels over the same position in an xy-plane. In such a model, calculated particle trajectories vary as synoptic scale wind varies. At all sampling times, the particles are connected to form a segmented plume centerline. The lateral and vertical dimensions of the plume are determined by a parameterization of turbulence scale diffusion. The impetus for the development of this model arose from the need of the U. S. Nuclear Regulatory Commission to assess radiological effects resulting from routine nuclear power reactor operations, as outlined in U. S. Nuclear Regulatory Guide 1.111.

  8. Air-stable short-wave infrared PbS colloidal quantum dot photoconductors passivated with Al{sub 2}O{sub 3} atomic layer deposition

    SciTech Connect

    Hu, Chen; Gassenq, Alban; Chen, Hongtao; Roelkens, Günther; Justo, Yolanda; Hens, Zeger; Devloo-Casier, Kilian; Detavernier, Christophe

    2014-10-27

    A PbS colloidal quantum dot photoconductor with Al{sub 2}O{sub 3} atomic layer deposition (ALD) passivation for air-stable operation is presented. Two different types of inorganic ligands for the quantum dots, S{sup 2−} and OH{sup −}, are investigated. PbS/S{sup 2−} photoconductors with a cut-off wavelength up to 2.4 μm are obtained, and a responsivity up to 50 A/W at 1550 nm is reported. The corresponding specific detectivity is ∼3.4 × 10{sup 8} Jones at 230 K. The 3-dB bandwidth of the PbS/S{sup 2−} and PbS/OH{sup −} photodetectors is 40 Hz and 11 Hz, respectively.

  9. Investigation and hazard assessment of the 2003 and 2007 Staircase Falls rock falls, Yosemite National Park, California, USA

    USGS Publications Warehouse

    Wieczorek, G.F.; Stock, Gregory M.; Reichenbach, P.; Snyder, J.B.; Borchers, J.W.; Godt, J.W.

    2008-01-01

    Since 1857 more than 600 rock falls, rock slides, debris slides, and debris flows have been documented in Yosemite National Park, with rock falls in Yosemite Valley representing the majority of the events. On 26 December 2003, a rock fall originating from west of Glacier Point sent approximately 200 m 3 of rock debris down a series of joint-controlled ledges to the floor of Yosemite Valley. The debris impacted talus near the base of Staircase Falls, producing fragments of flying rock that struck occupied cabins in Curry Village. Several years later on 9 June 2007, and again on 26 July 2007, smaller rock falls originated from the same source area. The 26 December 2003 event coincided with a severe winter storm and was likely triggered by precipitation and/or frost wedging, but the 9 June and 26 July 2007 events lack recognizable triggering mechanisms. We investigated the geologic and hydrologic factors contributing to the Staircase Falls rock falls, including bedrock lithology, weathering, joint spacing and orientations, and hydrologic processes affecting slope stability. We improved upon previous geomorphic assessment of rock-fall hazards, based on a shadow angle approach, by using STONE, a three-dimensional rock-fall simulation computer program. STONE produced simulated rock-fall runout patterns similar to the mapped extent of the 2003 and 2007 events, allowing us to simulate potential future rock falls from the Staircase Falls detachment area. Observations of recent rock falls, mapping of rock debris, and simulations of rock fall runouts beneath the Staircase Falls detachment area suggest that rock-fall hazard zones extend farther downslope than the extent previously defined by mapped surface talus deposits.

  10. How air influences radiation dose deposition in multiwell culture plates: a Monte Carlo simulation of radiation geometry

    PubMed Central

    Sabater, Sebastia; Berenguer, Roberto; Honrubia-Gomez, Paloma; Rivera, Miguel; Nuñez, Ana; Jimenez-Jimenez, Esther; Martos, Ana; Ramirez-Castillejo, Carmen

    2014-01-01

    Radiation of experimental culture cells on plates with various wells can cause a risk of underdosage as a result of the existence of multiple air–water interfaces. The objective of our study was to quantify this error in culture plates with multiple wells. Radiation conditions were simulated with the GAMOS code, based on the GEANT4 code, and this was compared with a simulation performed with PENELOPE and measured data. We observed a slight underdosage of ∼4% on the most superficial half of the culture medium. We believe that this underdosage does not have a significant effect on the dose received by culture cells deposited in a monolayer and adhered to the base of the wells. PMID:24722683

  11. An approach to assess the Particulate Matter exposure for the population living around a cement plant: modelling indoor air and particle deposition in the respiratory tract.

    PubMed

    Sánchez-Soberón, Francisco; Mari, Montse; Kumar, Vikas; Rovira, Joaquim; Nadal, Martí; Schuhmacher, Marta

    2015-11-01

    In this paper we studied the exposure to three size fractions of outdoor particulate matter (PM10, PM2.5, and PM1) collected in an area influenced by a cement plant. For that purpose, three groups of population were evaluated (children, adults and retired) in two seasons (summer and winter). Outdoor measured PM concentrations, as well as physiological parameters and activity patterns of the three groups of population were used as input data in two different models. The first one was an indoor air quality model, used to elucidate indoor PM concentrations in different microenvironments. The second one was a dosimetry model, used to evaluate the internal exposure and the distribution of the different PM fractions in the respiratory tract. Results from the indoor air quality model showed that special attention must be paid to the finest particles, since they penetrate indoors in a greater degree. Highest pulmonary doses for the three PM sizes were reported for retired people, being this a result of the high amount of time in outdoor environments exercising lightly. For children, the exposure was mainly influenced by the time they also spend outdoors, but in this case due to heavy intensity activities. It was noticed that deposition of fine particles was more significant in the pulmonary regions of children and retired people in comparison with adults, which has implications in the expected adverse health effects for those vulnerable groups of population.

  12. Occurrence, phase distribution and depositional intensity of dichlorodiphenyltrichloroethane (DDT) and its metabolites in air and precipitation of the Pearl River Delta, China.

    PubMed

    Yue, Qiang; Zhang, Kai; Zhang, Bao-Zhong; Li, Shao-Meng; Zeng, Eddy Y

    2011-07-01

    Concentrations of dichlorodiphenyltrichloroethane (DDT) and its metabolites (designated as DDTs, the sum of o,p'- and p,p'-DDT, o,p'- and p,p'-DDE, and o,p'- and p,p'-DDD) in air and precipitation from the Pearl River Delta (PRD) of China were determined. Total concentrations of DDTs in air (gas+particle) and precipitation (dissolved+particle) were 170 ± 120 pg m(-3) and 940 ± 180 pg L(-1) for Dongguan (rural) and 240 ± 120 pg m(-3) and 790 ± 140 pg L(-1) for Shunde (rural), respectively, while they were 1550 ± 640 pg L(-1) in precipitation from Guangzhou (urban). Log-transformed partition coefficients between air and particulate organic matter (log K(oa)(')) of p,p'-DDT, p,p'-DDE, p,p'-DDD, o,p'-DDT, o,p'-DDE, and o,p'-DDD were 9.64 ± 0.58, 10.07 ± 0.56, 9.90 ± 0.76, 10.06 ± 0.66, 10.02 ± 0.72, and 10.13 ± 0.57, respectively; while those between water and particulate organic matter (log K(om)(')) were 6.58 ± 0.66, 6.36 ± 0.53, 6.01 ± 0.62, 6.41 ± 0.42, 5.98 ± 0.76, and 5.95 ± 0.66, respectively. Total washout ratios by bulk rainfalls ranged from 4600 for o,p'-DDT to 54,000 for p,p'-DDT. Estimated average dry particle and wet depositional intensities in the PRD were 2.1 × 10(-6) and 1.6 × 10(-6)gm(-2)y(-1).

  13. Occurrence of polybrominated diphenyl ethers in air and precipitation of the Pearl River Delta, South China: annual washout ratios and depositional rates.

    PubMed

    Zhang, Bao-Zhong; Guan, Yu-Feng; Li, Shao-Meng; Zeng, Eddy Y

    2009-12-15

    On the basis of a one-year (from October 2006 to September 2007) sampling campaign, 34 air samples and 23 bulk precipitation samples were collected in the Pearl River Delta (PRD) in southern China and analyzed for polybrominated diphenyl ethers (PBDEs). Fifteen tri- to deca-BDE congeners (sum of which is defined as Sigma15PBDE) were detected in more than 70% of the samples. In three urban-rural regions, Sigma15PBDE concentrations ranged from 77 to 372 pg/m3 in air (particulate + vapor) and 1.98 to 15.5 ng/L in rain (particle+dissolved) from Dongguan, from 195 to 1450 pg/m3 in air and 4.71 to 17.2 ng/L in rain from Shunde, and from 23.7 to 148 ng/L in rain from Guangzhou. Among the BDE congeners, BDE-209 was the predominant component. Linear correlations between the gas-particle partition coefficients (Kp) and the subcooled vapor pressures (P(O/L)) of individual BDE congeners were observed for both the wet and dry seasons, but the slopes (-0.572 to -0.525) of the fitted equations all substantially deviated from equilibrium condition (slope = -1). The total washout ratio by bulk rainfalls was determined to be 2 x 103 for tri-BDEs and 6 x 104 for BDE-209. The estimated annual dry and wet depositional rates were 6720 and 2460 kg/yr, respectively, for BDE-209, and 7270 and 2940 kg/yr for Sigma15PBDE in the PRD, indicating a dominant pathway for PBDEs input into the PRD soil and aquatic environments.

  14. Falling into Winter.

    ERIC Educational Resources Information Center

    Harrington, Carolyn Lang

    2000-01-01

    Presents an activity that connects art, science, and nature in which elementary school students learn about deciduous trees. Explains that students create a torn-tissue collage, using fall colors for a background and drawing a silhouette of a tree without leaves on top of the background with black crayon. (CMK)

  15. Education and Falling Wages.

    ERIC Educational Resources Information Center

    Thurow, Lester C.

    1994-01-01

    Discusses why today's American workforce is experiencing falling wages and suggests that the answer to reversing this trend lies in improving the American education system to world class levels. Suggests the need to develop a postsecondary training system for those who do not go on to college, and highlights ways this might be implemented. (GR)

  16. Fall 2013 International Comparisons

    ERIC Educational Resources Information Center

    Northwest Evaluation Association, 2014

    2014-01-01

    This Fall report is an aggregated statistical analysis of Measures of Academic Progress® (MAP®) data from international schools. The report provides a consistent means of comparisons of specific sub-groups by subject and grade, which allows partners to compare their MAP® results with other schools within their region or membership organization.…

  17. Freshmen Survey. Fall 1985.

    ERIC Educational Resources Information Center

    Goodyear, Don

    In 1985, College of the Sequoias (COS) was asked by the Cooperative Institutional Research Program (conducted jointly by the American Council on Education and the University of California, Los Angeles) to participate in a survey of incoming freshmen for the fall 1985 semester. During the summer counseling session, 259 new COS freshmen were…

  18. The News, Fall 2002.

    ERIC Educational Resources Information Center

    Giles, Ray, Ed.

    2002-01-01

    This fall 2002 newsletter from the Community College League of California contains several articles, news stories, and the brochure from the 2002 Annual Convention, "Celebrating the Way California LEARNS." Articles include: (1) "Nursing Shortage Poses Dilemma for Colleges: Access vs. Efficiency," a discussion of the debate over how to increase the…

  19. Editors' Fall Picks

    ERIC Educational Resources Information Center

    Heilbrun, Margaret; McCormack, Heather; Katterjohn, Anna; Kuzyk, Raya; Roncevic, Mirela; Fox, Bette-Lee; Hoffert, Barbara

    2009-01-01

    "Library Journal's" review editors select fall titles readers won't want to miss--"Waiting on a Train: The Embattled Future of Passenger Rail Service" (James McCommons); "Happy" (Alex Lemon); "Free for All: Joe Papp, the Public, and the Greatest Theater Story Ever Told" (Kenneth Turan & Joseph Papp); "In My Father's Shadow: A Daughter Remembers…

  20. Precision Falling Body Experiment

    ERIC Educational Resources Information Center

    Blackburn, James A.; Koenig, R.

    1976-01-01

    Described is a simple apparatus to determine acceleration due to gravity. It utilizes direct contact switches in lieu of conventional photocells to time the fall of a ball bearing. Accuracies to better than one part in a thousand were obtained. (SL)

  1. In vitro exposures in diesel exhaust atmospheres: resuspension of PM from filters versus direct deposition of PM from air.

    PubMed

    Lichtveld, Kim M; Ebersviller, Seth M; Sexton, Kenneth G; Vizuete, William; Jaspers, Ilona; Jeffries, Harvey E

    2012-08-21

    One of the most widely used in vitro particulate matter (PM) exposures methods is the collection of PM on filters, followed by resuspension in a liquid medium, with subsequent addition onto a cell culture. To avoid disruption of equilibria between gases and PM, we have developed a direct in vitro sampling and exposure method (DSEM) capable of PM-only exposures. We hypothesize that the separation of phases and post-treatment of filter-collected PM significantly modifies the toxicity of the PM compared to direct deposition, resulting in a distorted view of the potential PM health effects. Controlled test environments were created in a chamber that combined diesel exhaust with an urban-like mixture. The complex mixture was analyzed using both the DSEM and concurrently collected filter samples. The DSEM showed that PM from test atmospheres produced significant inflammatory response, while the resuspension exposures at the same exposure concentration did not. Increasing the concentration of resuspended PM sixteen times was required to yield measurable IL-8 expression. Chemical analysis of the resuspended PM indicated a total absence of carbonyl compounds compared to the test atmosphere during the direct-exposures. Therefore, collection and resuspension of PM into liquid modifies its toxicity and likely leads to underestimating toxicity.

  2. In Vitro Exposures in Diesel Exhaust Atmospheres: Resuspension of PM from Filters Verses Direct Deposition of PM from Air

    PubMed Central

    Lichtveld, Kim M.; Ebersviller, Seth M.; Sexton, Kenneth G.; Vizuete, William; Jaspers, Ilona; Jeffries, Harvey E.

    2012-01-01

    One of the most widely used in vitro particulate matter (PM) exposures methods is the collection of PM on filters, followed by resuspension in a liquid medium, with subsequent addition onto a cell culture. To avoid disruption of equilibria between gases and PM, we have developed a direct in vitro sampling and exposure method (DSEM) capable of PM-only exposures. We hypothesize that the separation of phases and post-treatment of filter-collected PM significantly modifies the toxicity of the PM compared to direct deposition, resulting in a distorted view of the potential PM health effects. Controlled test environments were created in a chamber that combined diesel exhaust with an urban-like mixture. The complex mixture was analyzed using both the DSEM and concurrently-collected filter samples. The DSEM showed that PM from test atmospheres produced significant inflammatory response, while the resuspension exposures at the same exposure concentration did not. Increasing the concentration of resuspended PM sixteen times was required to yield measurable IL-8 expression. Chemical analysis of the resuspended PM indicated a total absence of carbonyl compounds compared to the test atmosphere during the direct-exposures. Therefore, collection and resuspension of PM into liquid modifies its toxicity and likely leads to underestimating toxicity. PMID:22834915

  3. The role of entrainment by falling raindrops in microbursts

    NASA Technical Reports Server (NTRS)

    Krueger, Steven K.

    1988-01-01

    The numerical model of Krueger et al. (1986) for dry microburst simulations is used to study the role of entrainment by falling raindrops. Two series of numerical simulations were conducted: a control series, and a series with the raindrop fall speed set to zero so that the rain moved with the air instead of falling through it. The results show that entrainment due to falling raindrops helps microbursts with large raindrop mixing ratios to form in stable stratifications. It is found that entrainment appears to contribute to the small spatial and temporal scales that characterize microburst outflows.

  4. Short- and medium-chain chlorinated paraffins in air and soil of subtropical terrestrial environment in the pearl river delta, South China: distribution, composition, atmospheric deposition fluxes, and environmental fate.

    PubMed

    Wang, Yan; Li, Jun; Cheng, Zhineng; Li, Qilu; Pan, Xiaohui; Zhang, Ruijie; Liu, Di; Luo, Chunling; Liu, Xiang; Katsoyiannis, Athanasios; Zhang, Gan

    2013-03-19

    Research on the environmental fate of short- and medium-chain chlorinated paraffins (SCCPs and MCCPs) in highly industrialized subtropical areas is still scarce. Air, soil, and atmospheric deposition process in the Pearl River Delta of South China were investigated, and the average SCCP and MCCP concentrations were 5.2 μg/sampler (17.69 ng/m(3)) and 4.1 μg/sampler for passive air samples, 18.3 and 59.3 ng/g for soil samples, and 5.0 and 5.3 μg/(m(2)d) for deposition samples, respectively. Influenced by primary sources and the properties of chlorinated paraffins (CPs), a gradient trend of concentrations and a fractionation of composition from more to less industrialized areas were discovered. Intense seasonal variations with high levels in summer air and winter deposition samples indicated that the air and deposition CP levels were controlled mainly by the vapor and particle phase, respectively. Complex environmental processes like volatilization and fractionation resulted in different CP profiles in different environment matrixes and sampling locations, with C(10-11) C(l6-7) and C(14) C(l6-7), C(10-12) C(l6-7) and C(14) C(l6-8), and C(11-12) C(l6-8) and C(14) C(l7-8) dominating in air, soil, and atmospheric deposition, respectively. Shorter-chain and less chlorinated congeners were enriched in air in the less industrialized areas, while longer-chain and higher chlorinated congeners were concentrated in soil in the more industrialized areas. This is suggesting that the gaseous transport of CPs is the dominant mechanism responsible for the higher concentrations of lighter and likely more mobile CPs in the rural areas.

  5. A comparison of air dispersion models for estimating PM2.5 and dry deposition to urban trees

    NASA Astrophysics Data System (ADS)

    Game, Ibrahim Paguedame

    Many cities have public health issues linked to air pollution; various tools are used to assess pollutant distribution and removal by urban trees to help alleviate some of these issues. This research compares the predicted PM2.5 concentrations from the US EPA's AERMOD, the USDA Forest Service's i-Tree-Eco-D, the US EPA's Fused HBM data to short- and long-term monitors in New York City. AERMOD generally performs better than the US EPA's Fuse and i-Tree-Eco-D. On days with lower PM2.5 concentrations, Fuse appears to better capture the spatial distribution of PM2.5 than the other models, though on days with high PM2.5, Fuse had a larger negative bias. i-Tree-Eco-D was improved by raising the height of mobile emissions. Predictions from Fuse lead to higher estimates of PM2.5 removal and human health benefits, while AERMOD produced the lowest; and the removal varied across boroughs in NYC.

  6. Rock-fall potential in the Yosemite Valley, California

    USGS Publications Warehouse

    Wieczorek, G.F.; Morrissey, M.M.; Iovine, Giulio; Godt, Jonathan

    1999-01-01

    We used two methods of estimating rock-fall potential in the Yosemite Valley, California based on (1) physical evidence of previous rock-fall travel, in which the potential extends to the base of the talus, and (2) theoretical potential energy considerations, in which the potential can extend beyond the base of the talus, herein referred to as the rock-fall shadow. Rock falls in the valley commonly range in size from individual boulders of less than 1 m3 to moderate-sized falls with volumes of about 100,000 m3. Larger rock falls exceeding 100,000 m3, referred to as rock avalanches, are considered to be much less likely to occur based on the relatively few prehistoric rock-fall avalanche deposits in the Yosemite Valley. Because the valley has steep walls and is relatively narrow, there are no areas that are absolutely safe from large rock avalanches. The map shows areas of rock-fall potential, but does not predict when or how frequently a rock fall will occur. Consequently, neither the hazard in terms of probability of a rock fall at any specific location, nor the risk to people or facilities to such events can be assessed from this map.

  7. Dry Deposition Estimates in Texas during Drought Years

    NASA Astrophysics Data System (ADS)

    Huang, L.; Kimura, Y.; McDonald-Buller, E.; McGaughey, G.; Allen, D.

    2014-12-01

    Severe drought has been a recurring phenomenon in the southwestern United States. Most climate models suggest that droughts will become more frequent in the future as climate changes in response to increased concentrations of greenhouse gases and other radiative forcing species in the atmosphere. Drought-induced changes in natural and anthropogenically managed and cultivated land cover systems have the potential to affect air quality. Dry deposition refers to the process by which trace gases and particulates in the atmosphere are transferred to the Earth's surface, including to soil, vegetation, and water, in the absence of precipitation. It is a primary physical removal mechanism for ozone during the warm spring through early fall seasons in Texas. As the state endeavors to achieve and maintain attainment with the National Ambient Air Quality Standards (NAAQS) for ozone, it is important to understand the impacts of drought conditions on estimates of dry deposition. This research explores the interannual variations in predicted dry deposition velocities and component surface resistances of ozone in eastern Texas during 2006-2011, including years with severe to exceptional drought conditions (e.g. 2011) as well as years with average to above average precipitation patterns (e.g. 2007). Two widely used dry deposition algorithms that have been incorporated within the Comprehensive Air Quality Model with Extensions (CAMx), the photochemical grid model used to support air quality planning efforts in Texas, are used in offline simulations.

  8. Reduction in falling after a falls-assessment.

    PubMed

    Hansma, A H G; Emmelot-Vonk, M H; Verhaar, H J J

    2010-01-01

    The aim of this single-center retrospective cohort study was to evaluate the effect of a multidisciplinary falls-assessment, consisting of identification and possible modification of risk factors for falls, on the frequency of falls among elderly individuals attending the geriatric outpatient department of the University Medical Center (UMC) Utrecht, the Netherlands. The characteristics of 70 elderly people who visited the outpatient department because of a fall in the period from May 2005 till February 2007 were evaluated. The effectiveness of the falls-assessment was evaluated by telephone interview of those individuals who had attended the falls-assessment. Fifty-three patients (mean age=79.8 years) were interviewed after a mean+/-S.D. of 1.47+/-0.41 years (ranging 0.72-2.34 years) subsequent to the falls-assessment. Falls-assessment led to significantly fewer falls, from 3.78+/-4.66 at the time of the assessment at baseline to 1.10+/-1.86 at the time of the interview (p=0.000041). Fear of falling was also significantly diminished. In conclusion, falls-assessment leads to fewer falls and less fear of falling among elderly individuals.

  9. Controlled deposition of functionalized silica coated zinc oxide nano-assemblies at the air/water interface for blood cancer detection.

    PubMed

    Pandey, Chandra Mouli; Dewan, Srishti; Chawla, Seema; Yadav, Birendra Kumar; Sumana, Gajjala; Malhotra, Bansi Dhar

    2016-09-21

    We report results of the studies relating to controlled deposition of the amino-functionalized silica-coated zinc oxide (Am-Si@ZnO) nano-assemblies onto an indium tin oxide (ITO) coated glass substrate using Langmuir-Blodgett (LB) technique. The monolayers have been deposited by transferring the spread solution of Am-Si@ZnO stearic acid prepared in chloroform at the air-water interface, at optimized pressure (16 mN/m), concentration (10 mg/ml) and temperature (23 °C). The high-resolution transmission electron microscopic studies of the Am-Si@ZnO nanocomposite reveal that the nanoparticles have a microscopic structure comprising of hexagonal assemblies of ZnO with typical dimensions of 30 nm. The surface morphology of the LB multilayer observed by scanning electron microscopy shows uniform surface of the Am-Si@ZnO film in the nanometer range (<80 nm). These electrodes have been utilized for chronic myelogenous leukemia (CML) detection by covalently immobilizing the amino-terminated oligonucleotide probe sequence via glutaraldehyde as a crosslinker. The response studies of these fabricated electrodes carried out using electrochemical impedance spectroscopy show that this Am-Si@ZnO LB film based nucleic acid sensor exhibits a linear response to complementary DNA (10(-6)-10(-16) M) with a detection limit of 1 × 10(-16) M. This fabricated platform is validated with clinical samples of CML positive patients and the results demonstrate its immense potential for clinical diagnosis. PMID:27590542

  10. COMPARISON OF THERMAL PROPERTIES OF THERMAL BARRIER COATING DEPOSITED ON IN738 USING STANDARD AIR PLASMA SPRAY WITH 100HE PLASMA SPRAY SYSTEM

    SciTech Connect

    Uppu, N.; Mensah, P.F.; Ofori, D.

    2006-07-01

    A typical blade material is made of Nickel super alloy and can bear temperatures up to 950°C. But the operating temperature of a gas turbine is above the melting point of super alloy nearly at 1500°C. This could lead to hot corrosions, high temperature oxidation, creep, thermal fatigue may takes place on the blade material. Though the turbine has an internal cooling system, the cooling is not adequate to reduce the temperature of the blade substrate. Therefore to protect the blade material as well as increase the efficiency of the turbine, thermal barrier coatings (TBCs) must be used. A TBC coating of 250 μm thick can reduce the temperature by up to 200° C. Air Plasma Spray Process (APS) and High Enthalpy Plasma Spray Process (100HE) were the processes used for coating the blades with the TBCs. Because thermal conductivity increases with increase in temperature, it is desired that these processes yield very low thermal conductivities at high temperatures in order not to damage the blade. An experiment was carried out using Flash line 5000 apparatus to compare the thermal conductivity of both processes.The apparatus could also be used to determine the thermal diffusivity and specific heat of the TBCs. 75 to 2800 K was the temperature range used in the experimentation. It was found out that though 100HE has high deposition efficiency, the thermal conductivity increases with increase in temperatures whiles APS yielded low thermal conductivities.

  11. `In free fall'

    NASA Astrophysics Data System (ADS)

    Beijerinck, Herman C. W.

    2014-01-01

    Physicists in the lead of a fiction book or a play, that's a rare event! Writers in general do not understand physics, while physicists seldom have the talent of writing for a large audience. So when it happens, we should rejoice. The up-and-coming German author Juli Zeh [1] (1974), who studied law, has succeeded in combining beautiful prose, psychological drama, crime and physics in a challenging book `In free fall' [2]. A good friend of hers, Bettina Bruinier, has put the core message of the book into a compelling play in the `Volkstheater' in Munich [1]. Yes, it can be done.

  12. Spatial distribution and seasonal variation of atmospheric bulk deposition of polycyclic aromatic hydrocarbons in Beijing–Tianjin region, North China

    PubMed Central

    Wang, Wentao; Simonich, Staci L. Massey; Giri, Basant; Xue, Miao; Zhao, Jingyu; Chen, Shejun; Shen, Huizhong; Shen, Guofeng; Wang, Rong; Cao, Jun; Tao, Shu

    2013-01-01

    Bulk deposition samples were collected in remote, rural village and urban areas of Beijing–Tianjin region, North China in spring, summer, fall and winter from 2007 to 2008. The annually averaged PAHs concentration and deposition flux were 11.81 ± 4.61 µg/g and 5.2 ± 3.89 µg/m2/day respectively. PHE and FLA had the highest deposition flux, accounting for 35.3% and 20.7% of total deposition flux, respectively. More exposure risk from deposition existed in the fall for the local inhabitants. In addition, the PAHs deposition flux in rural villages (3.91 µg/m2/day) and urban areas (8.28 µg/m2/day) was 3.8 and 9.1 times higher than in background area (0.82 µg/m2/day), respectively. This spatial variation of deposition fluxes of PAHs was related to the PAHs emission sources, local population density and air concentration of PAHs, and the PAHs emission sources alone can explain 36%, 49%, 21% and 30% of the spatial variation in spring, summer, fall and winter, respectively. PMID:20888097

  13. Ambient air particulates and particulate-bound mercury Hg(p) concentrations: dry deposition study over a Traffic, Airport, Park (T.A.P.) areas during years of 2011-2012.

    PubMed

    Fang, Guor-Cheng; Lin, Yen-Heng; Zheng, Yu-Cheng

    2016-02-01

    The main purpose of this study was to monitor ambient air particles and particulate-bound mercury Hg(p) in total suspended particulate (TSP) concentrations and dry deposition at the Hung Kuang (Traffic), Taichung airport and Westing Park sampling sites during the daytime and nighttime, from 2011 to 2012. In addition, the calculated/measured dry deposition flux ratios of ambient air particles and particulate-bound mercury Hg(p) were also studied with Baklanov & Sorensen and the Williams models. For a particle size of 10 μm, the Baklanov & Sorensen model yielded better predictions of dry deposition of ambient air particulates and particulate-bound mercury Hg(p) at the Hung Kuang (Traffic), Taichung airport and Westing Park sampling site during the daytime and nighttime sampling periods. However, for particulates with sizes 20-23 μm, the results obtained in the study reveal that the Williams model provided better prediction results for ambient air particulates and particulate-bound mercury Hg(p) at all sampling sites in this study.

  14. Development of fireside performance indices, Task 7.33, Development of methods to predict agglomeration and deposition in FBCS, Task 7.36, Enhanced air toxics control, Task 7.45

    SciTech Connect

    Zygarlicke, C.J.; Mann, M.D.; Laudal, D.L.; Miller, S.J.

    1994-01-01

    The Energy & Environmental Research Center (EERC) has been developing advanced indices that rank coals according to their fouling and slagging propensity in utility boilers. The indices are based on sophisticated analytical techniques for identifying and quantifying coal inorganics and are useful in predicting the effects of proposed operational changes on ash deposition in coal-fired boilers. These indices are intended to provide an economical way to reduce the amount of full-scale testing needed to determine the best means of minimizing ash-related problems. The successful design and operation of the fluidized-bed combustor requires the ability to control and mitigate ash-related problems. The major ash-related problems in FBC are agglomeration of bed material, ash deposition on heat-transfer surfaces, ash deposition on refractory and uncooled surfaces, corrosion, and erosion. The focus of the Development of Methods to Predict Agglomeration and Deposition in FBCs is on the agglomeration and deposition problems in atmospheric bubbling and circulating beds. The 1990 Clean Air Act Amendments require study of air toxic emissions from coal combustion systems. Since most of the toxic metals present in coal will be in particulate form, a high level of fine-particle control appears to be the best approach to achieving a high level of air toxics control. However, over 50% of mercury and a portion of selenium emissions are in vapor form and are not typically collected in particulate control devices. Therefore, the goal of this project is to develop methods that capture the vapor-phase metals while simultaneously achieving ultrahigh collection efficiency of particulate air toxics.

  15. Catching a Falling Star

    NASA Astrophysics Data System (ADS)

    2004-07-01

    , etc. This image was obtained by MASCOT on August 25, 2002 and shows a meteor caught in the act. (Note that this is not the meteor whose spectrum was recorded). The Milky Way is also clearly visible in the centre. A popular saying states that when you see a meteor, you may make a wish. While astronomers cannot promise that it will be realised, a team of astronomers [1] have indeed seen a dream come true! On May 12, 2002, they were lucky to record the spectrum of a bright meteor when it happened - by sheer chance and against all reasonable odds - to cross the narrow slit of the FORS1 instrument on the ESO Very Large Telescope. At the time of this unlikely event, the telescope was performing a series of 20-minute spectroscopic exposures of a supernova in a distant galaxy in order to establish constraints on the dark energy content of the Universe (see e.g. ESO PR 21/98). Thanks to its enormous light-collecting and magnifying power, the VLT recorded the spectrum of the meteor trail perpendicular to its path on one of these exposures. "We really hit the jackpot", says ESO astronomer Emmanuel Jehin: "Chances of capturing a meteor in the narrow slit of the FORS1 spectrograph are about as big as for me winning the national lottery." Meteor spectra have on occasion been obtained serendipitously during photographic star spectra surveys. But this is now maybe the only meteor spectrum recorded with a large telescope and a modern spectrograph. The spectrum covers the wavelength range from 637 to 1050 nm, which is dominated by emissions from air atoms and molecules in the meteor path and teach us about the collision processes in the wake of a meteoroid. The rapid motion of the meteor across the sky resulted in a very brief exposure while crossing the narrow spectrograph slit - only 1/50 of a millisecond! - and despite the relative brightness of the meteor it was only thanks to the VLT's great light-gathering power that any record was procured. The meteor was estimated at magnitude

  16. How to catch a falling fruit

    NASA Astrophysics Data System (ADS)

    Marantan, Andrew; Mahadevan, Lakshminarayanan

    2015-03-01

    A variety of fish engage in complex hunting behaviors involving catching airborne prey falling to the surface of the water. In principle this requires that the fish develop internal models describing both the falling prey and its own motion relative to that prey. However learning such models is complicated by the fact that the fish must also account for noise in optical measurements and the refraction occurring at the air/water interface. Inspired by experimental observations, we describe how one such species (Brycon guatemalensis) might feasibly overcome these obstacles and learn a model accurate enough to catch falling fruit. Instead of learning a model for how the fruit falls and a model for how it moves in the water and a model accounting for refraction, we argue that the fish could instead learn one approximate linear model relating a set of measured inputs to a set of measured outputs valid in a limited domain of initial conditions. The fish could then make its control decisions based on the outcome predicted by this combined linear model. We also discuss how the fish can leverage neural transformations of raw data to learn a model with a larger domain of validity and yet more sensitive to noise due to nontrivial Jacobians arising from the neural transformations.

  17. Energy Matters - Fall 2002

    SciTech Connect

    2002-09-01

    Quarterly newsletter from DOE's Industrial Technologies Program to promote the use of energy-efficient industrial systems. This issue focus of this edition of the Energy Matters Newsletter is on energy and environmental issues. Read more about compressed air's role in productivity, making good motor decisions, and more.

  18. Comparison of precipitation chemistry measurements obtained by the Canadian Air and Precipitation Monitoring Network and National Atmospheric Deposition Program for the period 1995-2004

    USGS Publications Warehouse

    Wetherbee, Gregory A.; Shaw, Michael J.; Latysh, Natalie E.; Lehmann, Christopher M.B.; Rothert, Jane E.

    2010-01-01

    Precipitation chemistry and depth measurements obtained by the Canadian Air and Precipitation Monitoring Network (CAPMoN) and the US National Atmospheric Deposition Program/National Trends Network (NADP/NTN) were compared for the 10-year period 1995–2004. Colocated sets of CAPMoN and NADP instrumentation, consisting of precipitation collectors and rain gages, were operated simultaneously per standard protocols for each network at Sutton, Ontario and Frelighsburg, Ontario, Canada and at State College, PA, USA. CAPMoN samples were collected daily, and NADP samples were collected weekly, and samples were analyzed exclusively by each network’s laboratory for pH, H + , Ca2+  , Mg2+  , Na + , K + , NH+4 , Cl − , NO−3 , and SO2−4 . Weekly and annual precipitation-weighted mean concentrations for each network were compared. This study is a follow-up to an earlier internetwork comparison for the period 1986–1993, published by Alain Sirois, Robert Vet, and Dennis Lamb in 2000. Median weekly internetwork differences for 1995–2004 data were the same to slightly lower than for data for the previous study period (1986–1993) for all analytes except NO−3 , SO2−4 , and sample depth. A 1994 NADP sampling protocol change and a 1998 change in the types of filters used to process NADP samples reversed the previously identified negative bias in NADP data for hydrogen-ion and sodium concentrations. Statistically significant biases (α = 0.10) for sodium and hydrogen-ion concentrations observed in the 1986–1993 data were not significant for 1995–2004. Weekly CAPMoN measurements generally are higher than weekly NADP measurements due to differences in sample filtration and field instrumentation, not sample evaporation, contamination, or analytical laboratory differences.

  19. Impact force of a falling drop

    NASA Astrophysics Data System (ADS)

    Soto, Dan; Clanet, Cristophe; Quere, David; Xavier Boutillon Collaboration

    2012-11-01

    Controlling droplet deposition is crucial in many industrial processes such as spraying pesticides on crops, inkjet printing or spray coating. Therefore, the dynamics of drop impacts have been extensively studied for more than one century. However, few literature describe the impacting force of a drop on a solid flat surface, although it might be a way to measure the size distribution of a collection of falling drops. We investigated experimentally how the instantaneous force at impact depends on impact velocity and drop radius. We also propose a new model to understand our observations. Physique et Mecanique des Milieux Heterogenes, CNRS, ESPCI, Paris France & Ladhyx, CNRS, Ecole Polytechnique, Palaiseau, France.

  20. Preventing falls and fall-related injuries in hospitals.

    PubMed

    Oliver, David; Healey, Frances; Haines, Terry P

    2010-11-01

    Falls are a widespread concern in hospitals settings, with whole hospital rates of between 3 and 5 falls per 1000 bed-days representing around a million inpatient falls occurring in the United States each year. Between 1% and 3% of falls in hospitals result in fracture, but even minor injuries can cause distress and delay rehabilitation. Risk factors most consistently found in the inpatient population include a history of falling, muscle weakness, agitation and confusion, urinary incontinence or frequency, sedative medication, and postural hypotension. Based on systematic reviews, recent research, and clinical and ethical considerations, the most appropriate approach to fall prevention in the hospital environment includes multifactorial interventions with multiprofessional input. There is also some evidence that delirium avoidance programs, reducing sedative and hypnotic medication, in-depth patient education, and sustained exercise programs may reduce falls as single interventions. There is no convincing evidence that hip protectors, movement alarms, or low-low beds reduce falls or injury in the hospital setting. International approaches to developing and maintaining a fall prevention program suggest that commitment of management and a range of clinical and support staff is crucial to success.

  1. Ambient air metallic pollutant study at HAF areas during 2013-2014

    NASA Astrophysics Data System (ADS)

    Fang, Guor-Cheng; Kuo, Yu-Chen; Zhuang, Yuan-Jie

    2015-05-01

    This study characterized diurnal variations of the total suspended particulate (TSP) concentrations, dry deposition flux and dry deposition velocity of metallic elements at Taichung Harbor (Harbor), Gong Ming Junior High School (Airport) and Sha lu Farmland (Farmland) sampling sites in central Taiwan between August, 2013 and July, 2014 in this study. The result indicated that: 1) the ambient air particulate concentrations, dry depositions were displayed as Harbor > Farmland > Airport during the day time sampling period. However, dry deposition velocities were shown as Airport > Harbor > Farmland for this study. 2) The ambient air particulate concentrations, dry depositions were displayed as Airport > Harbor > Farmland during the night time sampling period. However, dry deposition velocities were shown as Farmland > Harbor > Airport for this study. 3) The metallic element Zn has the average highest concentrations at Airport, Harbor and Farmland among all the metallic elements during the day time sampling period in this study. 4) There were significant differences for the metallic elements (Cr, Cu, Zn and Pb) in dry depositions at these three characteristic sampling sites (HAF) for the night time sampling period. The only exception is metallic element Cd. It displayed that there were no significant differences for the metallic element Cd at the Airport and Farmland sampling sites during the night time sampling period. 5) The average highest values for the metallic element Cu in TSP among the three characteristic sampling sites occurred during the fall and winter seasons for this study. As for the dry depositions, the average highest values in dry deposition among the three characteristic sampling sites occurred during the spring and summer seasons for this study. 6) The average highest values for the metallic element Cd in TSP among the three characteristic sampling sites occurred during the spring and summer seasons for this study. As for the dry depositions, the

  2. 1991 Fall Meeting Report

    NASA Astrophysics Data System (ADS)

    Chapman, David S.

    The AGU 1991 Fall Meeting, held in San Francisco December 9-13, was the largest national AGU meeting ever held. Meeting participation continued the steady growth trend set throughout the previous decade. A total of 4,037 papers and posters were presented, and by Friday noon of the meeting over 5,500 members had registered.Several special events were scheduled to inform and engage members on societal and programmatic aspects of our science. AGU's Committee on Education and Human Resources sponsored an open forum that addressed opportunities and problems associated with dual-career couples. A discussion of NASA's strategic plan by Berrien Moore and Joseph Alexander drew a large audience, and a special session on societal aspects of the Mt. Pinatubo eruption drew an overflow crowd. Two special lectures— “Plumes, Plates, and Deep Earth Structure” by Don L. Anderson and “New Frontiers in Aeronomy: Effects of Global Atmospheric Change” by P. M. Banks-also drew overflow crowds.

  3. Not Just a Fall Tree

    ERIC Educational Resources Information Center

    Miller-Hewes, Kathy A.

    2004-01-01

    Trees burst with color in the northern states. Autumn leaves dust the ground. Painting the fall landscape is nothing new. Teachers have been doing it in classrooms for decades. The approach, however, can make the difference between whether the fall landscape is simply painting for fun, or a real learning experience. Students learn best when they…

  4. Project Profile Report. Fall 1993.

    ERIC Educational Resources Information Center

    Pennsylvania Coll. of Technology, Williamsport.

    Pennsylvania College of Technology's Project Profile seeks to provide a portrait of all students entering each fall by collecting and analyzing surveys completed at the time of admission and comparing them to previous years. This report presents data on the 4,942 students who applied and matriculated in fall 1993 and includes comparisons by…

  5. [FALLS IN PATIENTS WITH DEMENTIA].

    PubMed

    Aizen, Efraim

    2015-05-01

    Older people with dementia are at increased risk of falls and their consequences. Patients with dementia fall twice as often as elderly cognitively intact people and are at greater risk of injurious falls. Falls in older people with dementia cause higher rates of morbidity, mortality and institutionalization. There is limited literature attempting to show specific risk factors for falls in this population, mainly: Lewy body dementia, dementia related to Parkinson's disease and depression, psychotropic medication, functional disability and behavioral disturbances. The Physiological Profile Assessment (PPAJ has been found to be a good fall risk screening tool in this population. There are few trials that have shown limited effectiveness of targeted fall prevention programs in community-dwelling cognitively impaired elderly. The evidence from hospitals and residential care is not conclusive. However, it has been demonstrated that some interventions, primarily exercise interventions, can modify certain risk factors in patients with dementia. Further research is required in specifically targeting fall prevention in older people with dementia. PMID:26168645

  6. Automatic Fall Monitoring: A Review

    PubMed Central

    Pannurat, Natthapon; Thiemjarus, Surapa; Nantajeewarawat, Ekawit

    2014-01-01

    Falls and fall-related injuries are major incidents, especially for elderly people, which often mark the onset of major deterioration of health. More than one-third of home-dwelling people aged 65 or above and two-thirds of those in residential care fall once or more each year. Reliable fall detection, as well as prevention, is an important research topic for monitoring elderly living alone in residential or hospital units. The aim of this study is to review the existing fall detection systems and some of the key research challenges faced by the research community in this field. We categorize the existing platforms into two groups: wearable and ambient devices; the classification methods are divided into rule-based and machine learning techniques. The relative merit and potential drawbacks are discussed, and we also outline some of the outstanding research challenges that emerging new platforms need to address. PMID:25046016

  7. Cowlitz Falls Fish Passage.

    SciTech Connect

    1995-09-01

    The upper Cowlitz was once home to native salmon and steelhead. But the combined impacts of overharvest, farming, logging and road building hammered fish runs. And in the 1960s, a pair of hydroelectric dams blocked the migration path of ocean-returning and ocean-going fish. The lower Cowlitz still supports hatchery runs of chinook, coho and steelhead. But some 200 river miles in the upper river basin--much of it prime spawning and rearing habitat--have been virtually cut off from the ocean for over 26 years. Now the idea is to trap-and-haul salmon and steelhead both ways and bypass previously impassable obstacles in the path of anadromous fish. The plan can be summarized, for the sake of explanation, in three steps: (1) trap and haul adult fish--collect ocean-returning adult fish at the lowermost Cowlitz dam, and truck them upstream; (2) reseed--release the ripe adults above the uppermost dam, and let them spawn naturally, at the same time, supplement these runs with hatchery born fry that are reared and imprinted in ponds and net pens in the watershed; (3) trap and haul smolts--collection the new generation of young fish as they arrive at the uppermost Cowlitz dam, truck them past the three dams, and release them to continue their downstream migration to the sea. The critical part of any fish-collection system is the method of fish attraction. Scientists have to find the best combination of attraction system and screens that will guide young fish to the right spot, away from the turbine intakes. In the spring of 1994 a test was made of a prototype system of baffles and slots on the upriver face of the Cowlitz Falls Dam. The prototype worked at 90% efficiency in early tests, and it worked without the kind of expensive screening devices that have been installed on other dams. Now that the success of the attraction system has been verified, Harza engineers and consultants will design and build the appropriate collection part of the system.

  8. Air ejector augmented compressed air energy storage system

    DOEpatents

    Ahrens, Frederick W.; Kartsounes, George T.

    1980-01-01

    Energy is stored in slack demand periods by charging a plurality of underground reservoirs with air to the same peak storage pressure, during peak demand periods throttling the air from one storage reservoir into a gas turbine system at a constant inlet pressure until the air pressure in the reservoir falls to said constant inlet pressure, thereupon permitting air in a second reservoir to flow into said gas turbine system while drawing air from the first reservoir through a variable geometry air ejector and adjusting said variable geometry air ejector, said air flow being essentially at the constant inlet pressure of the gas turbine system.

  9. Air ejector augmented compressed air energy storage system

    DOEpatents

    Ahrens, F.W.; Kartsounes, G.T.

    Energy is stored in slack demand periods by charging a plurality of underground reservoirs with air to the same peak storage pressure, during peak demand periods throttling the air from one storage reservoir into a gas turbine system at a constant inlet pressure until the air presure in the reservoir falls to said constant inlet pressure, thereupon permitting air in a second reservoir to flow into said gas turbine system while drawing air from the first reservoir through a variable geometry air ejector and adjusting said variable geometry air ejector, said air flow being essentially at the constant inlet pressure of the gas turbine system.

  10. Falls in elderly hemodialysis patients.

    PubMed

    Abdel-Rahman, E M; Turgut, F; Turkmen, K; Balogun, R A

    2011-10-01

    The elderly, (age ≥ 65 years) hemodialysis (HD) patient population is growing rapidly across the world. The risk of accidental falls is very high in this patient population due to multiple factors which include aging, underlying renal disease and adverse events associated with HD treatments. Falls, the most common cause of fatal injury among elderly, not only increase morbidity and mortality, but also increase costs to the health system. Prediction of falls and interventions to prevent or minimize fall risk and associated complications will be a major step in helping these patients as well as decreasing financial and social burdens. Thus, it is vital to learn how to approach this important problem. In this review, we will summarize the epidemiology, risk factors, pathophysiology and complications of falls in elderly HD patients. We will also focus on available methods to assess and predict the patients at higher risk of falling and will provide recommendations for interventions to reduce the occurrence of falls in this population.

  11. Radar fall detectors: a comparison

    NASA Astrophysics Data System (ADS)

    Erol, Baris; Amin, Moeness; Ahmad, Fauzia; Boashash, Boualem

    2016-05-01

    Falls are a major cause of accidents in elderly people. Even simple falls can lead to severe injuries, and sometimes result in death. Doppler fall detection has drawn much attention in recent years. Micro-Doppler signatures play an important role for the Doppler-based radar systems. Numerous studies have demonstrated the offerings of micro-Doppler characteristics for fall detection. In this respect, a plethora of micro-Doppler signature features have been proposed, including those stemming from speech recognition and wavelet decomposition. In this work, we consider four different sets of features for fall detection. These can be categorized as spectrogram based features, wavelet based features, mel-frequency cepstrum coefficients, and power burst curve features. Support vector machine is employed as the classifier. Performance of the respective fall detectors is investigated using real data obtained with the same radar operating resources and under identical sensing conditions. For the considered data, the spectrogram based feature set is shown to provide superior fall detection performance.

  12. Atomic Layer Deposition of TiO2 for a High-Efficiency Hole-Blocking Layer in Hole-Conductor-Free Perovskite Solar Cells Processed in Ambient Air.

    PubMed

    Hu, Hang; Dong, Binghai; Hu, Huating; Chen, Fengxiang; Kong, Mengqin; Zhang, Qiuping; Luo, Tianyue; Zhao, Li; Guo, Zhiguang; Li, Jing; Xu, Zuxun; Wang, Shimin; Eder, Dominik; Wan, Li

    2016-07-20

    In this study we design and construct high-efficiency, low-cost, highly stable, hole-conductor-free, solid-state perovskite solar cells, with TiO2 as the electron transport layer (ETL) and carbon as the hole collection layer, in ambient air. First, uniform, pinhole-free TiO2 films of various thicknesses were deposited on fluorine-doped tin oxide (FTO) electrodes by atomic layer deposition (ALD) technology. Based on these TiO2 films, a series of hole-conductor-free perovskite solar cells (PSCs) with carbon as the counter electrode were fabricated in ambient air, and the effect of thickness of TiO2 compact film on the device performance was investigated in detail. It was found that the performance of PSCs depends on the thickness of the compact layer due to the difference in surface roughness, transmittance, charge transport resistance, electron-hole recombination rate, and the charge lifetime. The best-performance devices based on optimized TiO2 compact film (by 2000 cycles ALD) can achieve power conversion efficiencies (PCEs) of as high as 7.82%. Furthermore, they can maintain over 96% of their initial PCE after 651 h (about 1 month) storage in ambient air, thus exhibiting excellent long-term stability.

  13. Atomic Layer Deposition of TiO2 for a High-Efficiency Hole-Blocking Layer in Hole-Conductor-Free Perovskite Solar Cells Processed in Ambient Air.

    PubMed

    Hu, Hang; Dong, Binghai; Hu, Huating; Chen, Fengxiang; Kong, Mengqin; Zhang, Qiuping; Luo, Tianyue; Zhao, Li; Guo, Zhiguang; Li, Jing; Xu, Zuxun; Wang, Shimin; Eder, Dominik; Wan, Li

    2016-07-20

    In this study we design and construct high-efficiency, low-cost, highly stable, hole-conductor-free, solid-state perovskite solar cells, with TiO2 as the electron transport layer (ETL) and carbon as the hole collection layer, in ambient air. First, uniform, pinhole-free TiO2 films of various thicknesses were deposited on fluorine-doped tin oxide (FTO) electrodes by atomic layer deposition (ALD) technology. Based on these TiO2 films, a series of hole-conductor-free perovskite solar cells (PSCs) with carbon as the counter electrode were fabricated in ambient air, and the effect of thickness of TiO2 compact film on the device performance was investigated in detail. It was found that the performance of PSCs depends on the thickness of the compact layer due to the difference in surface roughness, transmittance, charge transport resistance, electron-hole recombination rate, and the charge lifetime. The best-performance devices based on optimized TiO2 compact film (by 2000 cycles ALD) can achieve power conversion efficiencies (PCEs) of as high as 7.82%. Furthermore, they can maintain over 96% of their initial PCE after 651 h (about 1 month) storage in ambient air, thus exhibiting excellent long-term stability. PMID:27340730

  14. Injuries due to falling coconuts.

    PubMed

    Barss, P

    1984-11-01

    Falling coconuts can cause injury to the head, back, and shoulders. A 4-year review of trauma admissions to the Provincial Hospital, Alotau, Milne Bay Province, Papua New Guinea, revealed that 2.5% of such admissions were due to being struck by falling coconuts. Since mature coconut palms may have a height of 24 up to 35 meters and an unhusked coconut may weigh 1 to 4 kg, blows to the head of a force exceeding 1 metric ton are possible. Four patients with head injuries due to falling coconuts are described. Two required craniotomy. Two others died instantly in the village after being struck by dropping nuts.

  15. Highlights of 2012 Fall Meeting

    NASA Astrophysics Data System (ADS)

    Finn, Carol

    2013-01-01

    This past December the streets of San Francisco, Calif., surrounding the Moscone Center were awash with a sea of Earth and space scientists attending the 45th consecutive AGU Fall Meeting, eager to share and expand their knowledge "for the benefit of humanity." As it has for many years, attendance at AGU's Fall Meeting—the largest gathering of Earth and space scientists in the world—continued to increase, this year passing the 24,000 mark. Attendees at the meeting, which took place on 3-7 December 2012, hailed from 97 countries; nearly 7000 of them were students. News from the Fall Meeting was carried in newspapers and on Web sites around the world, and the social media sphere lit up with talk of AGU and the Fall Meeting. It's even reported that for a short time we were a trending topic on Twitter.

  16. Exercises to help prevent falls

    MedlinePlus

    ... D, Dempster DW, Luckey M, Cauley J, eds. Osteoporosis . 4th ed. Philadelphia, PA: Elsevier; 2013:chap 70. Donath L, van Dieen J, Faude O. Exercise-based fall prevention in the elderly: what about ...

  17. Community College Estimated Growth: Fall 2010

    ERIC Educational Resources Information Center

    Phillippe, Kent; Mullin, Christopher M.

    2011-01-01

    A survey from the American Association of Community Colleges (AACC) found that enrollment growth in fall 2010 slowed its pace at community colleges, increasing 3.2% from the previous year. This contrasts with more dramatic increases in recent years: more than 11% between fall 2008 and fall 2009, and nearly 17% between fall 2007 and fall 2009,…

  18. Barometric pressure and triaxial accelerometry-based falls event detection.

    PubMed

    Bianchi, Federico; Redmond, Stephen J; Narayanan, Michael R; Cerutti, Sergio; Lovell, Nigel H

    2010-12-01

    Falls and fall related injuries are a significant cause of morbidity, disability, and health care utilization, particularly among the age group of 65 years and over. The ability to detect falls events in an unsupervised manner would lead to improved prognoses for falls victims. Several wearable accelerometry and gyroscope-based falls detection devices have been described in the literature; however, they all suffer from unacceptable false positive rates. This paper investigates the augmentation of such systems with a barometric pressure sensor, as a surrogate measure of altitude, to assist in discriminating real fall events from normal activities of daily living. The acceleration and air pressure data are recorded using a wearable device attached to the subject's waist and analyzed offline. The study incorporates several protocols including simulated falls onto a mattress and simulated activities of daily living, in a cohort of 20 young healthy volunteers (12 male and 8 female; age: 23.7 ±3.0 years). A heuristically trained decision tree classifier is used to label suspected falls. The proposed system demonstrated considerable improvements in comparison to an existing accelerometry-based technique; showing an accuracy, sensitivity and specificity of 96.9%, 97.5%, and 96.5%, respectively, in the indoor environment, with no false positives generated during extended testing during activities of daily living. This is compared to 85.3%, 75%, and 91.5% for the same measures, respectively, when using accelerometry alone. The increased specificity of this system may enhance the usage of falls detectors among the elderly population.

  19. Barometric pressure and triaxial accelerometry-based falls event detection.

    PubMed

    Bianchi, Federico; Redmond, Stephen J; Narayanan, Michael R; Cerutti, Sergio; Lovell, Nigel H

    2010-12-01

    Falls and fall related injuries are a significant cause of morbidity, disability, and health care utilization, particularly among the age group of 65 years and over. The ability to detect falls events in an unsupervised manner would lead to improved prognoses for falls victims. Several wearable accelerometry and gyroscope-based falls detection devices have been described in the literature; however, they all suffer from unacceptable false positive rates. This paper investigates the augmentation of such systems with a barometric pressure sensor, as a surrogate measure of altitude, to assist in discriminating real fall events from normal activities of daily living. The acceleration and air pressure data are recorded using a wearable device attached to the subject's waist and analyzed offline. The study incorporates several protocols including simulated falls onto a mattress and simulated activities of daily living, in a cohort of 20 young healthy volunteers (12 male and 8 female; age: 23.7 ±3.0 years). A heuristically trained decision tree classifier is used to label suspected falls. The proposed system demonstrated considerable improvements in comparison to an existing accelerometry-based technique; showing an accuracy, sensitivity and specificity of 96.9%, 97.5%, and 96.5%, respectively, in the indoor environment, with no false positives generated during extended testing during activities of daily living. This is compared to 85.3%, 75%, and 91.5% for the same measures, respectively, when using accelerometry alone. The increased specificity of this system may enhance the usage of falls detectors among the elderly population. PMID:20805056

  20. Tephra fall clean-up in urban environments

    NASA Astrophysics Data System (ADS)

    Hayes, Josh L.; Wilson, Thomas M.; Magill, Christina

    2015-10-01

    Tephra falls impact urban communities by disrupting transport systems, contaminating and damaging buildings and infrastructures, and are potentially hazardous to human health. Therefore, prompt and effective tephra clean-up measures are an essential component of an urban community's response to tephra fall. This paper reviews case studies of tephra clean-up operations in urban environments around the world, spanning 50 years. It identifies methods used in tephra clean-up and assesses a range of empirical relationships between level of tephra accumulation and clean-up metrics such as collected tephra volume, costs, and duration of operations. Results indicate the volume of tephra collected from urban areas is proportional to tephra accumulation. Urban areas with small tephra accumulations (1,000 m3/km2 or an average of 1 mm thickness) may collect < 1% of the total deposit, whereas urban areas which experience large accumulations (> 50,000 m3/km2 or an average of 50 mm thickness) remove up to 80%. This relationship can inform impact and risk assessments by providing an estimate of the likely response required for a given tephra fall. No strong relationship was found between tephra fall accumulation and clean-up cost or duration for urban environments which received one-off tephra falls, suggesting that these aspects of tephra fall clean-up operations are context specific. Importantly, this study highlights the advantage of effective planning for tephra clean-up and disposal in potentially exposed areas.

  1. Airfoil deposition model

    NASA Technical Reports Server (NTRS)

    Kohl, F. J.

    1982-01-01

    The methodology to predict deposit evolution (deposition rate and subsequent flow of liquid deposits) as a function of fuel and air impurity content and relevant aerodynamic parameters for turbine airfoils is developed in this research. The spectrum of deposition conditions encountered in gas turbine operations includes the mechanisms of vapor deposition, small particle deposition with thermophoresis, and larger particle deposition with inertial effects. The focus is on using a simplified version of the comprehensive multicomponent vapor diffusion formalism to make deposition predictions for: (1) simple geometry collectors; and (2) gas turbine blade shapes, including both developing laminar and turbulent boundary layers. For the gas turbine blade the insights developed in previous programs are being combined with heat and mass transfer coefficient calculations using the STAN 5 boundary layer code to predict vapor deposition rates and corresponding liquid layer thicknesses on turbine blades. A computer program is being written which utilizes the local values of the calculated deposition rate and skin friction to calculate the increment in liquid condensate layer growth along a collector surface.

  2. Development of a state-of-the-art acid-deposition model for the South Coast Air Basin of California. Final report

    SciTech Connect

    Pandis, S.N.; Seinfeld, J.H.

    1989-03-25

    Three different aqueous-phase modules have been developed to describe the physicochemical processes associated with the aqueous-phase in the atmosphere. These modules constitute the central core of an urban-scale acid deposition model and can be incorporated into an Eulerian three dimensional grid-based system. The fog model (Module 2) has been implemented in a trajectory framework and has been employed to predict the temperature profile, fog development, liquid water content, gas and aqueous phase concentrations of pollutants, and wet deposition rates of main ionic species during the radiation fog episode in Bakersfield in the San Joaquin Valley of California over the period January 4-5, 1985.

  3. Research on flux of dry atmospheric falling dust and its characterization in a subtropical city, Guangzhou, South China.

    PubMed

    Zhao, Jinping; Peng, Ping'an; Song, Jianzhong; Ma, Shexia; Sheng, Guoying; Fu, Jiamo

    2010-09-01

    Guangzhou is the central city in the Pearl River Delta (PRD), China, and is one of the most polluted cities in the world. To characterize the ambient falling dust pollution, two typical sampling sites: urban (Wushan) and suburban (University Town) areas in Guangzhou city were chosen for falling dust collection over 1 year at time intervals of 1 or 2 months. The flux of dry deposition was calculated. In addition, mineral composition and morphology of atmospheric falling dust were studied by X-ray diffraction, scanning electron microscopy, and microscopic observation. The results revealed that the dust flux in Guangzhou city was 3.34-3.78 g/(m(2) month) during the study period. The main minerals in the dust were quartz, illite, calcite, kaolinite, gypsum, plagioclase, dolomite, and amorphous matter. The morphological types included grained and flaky individual minerals, chain-like aggregates, spherical flying beads, and irregular aggregates, with the chain-like and spherical aggregates indicators of industrial ash. The major dusts were derived from industrial and construction activities. The gypsum present in the dust collected in winter season was not only derived from cement dust but may also have originated from the reaction of calcic material with sulfuric acids resulting from photooxidation of SO(x) and NO(x), which confirmed serious air pollution due to SO(x) and NO(x) in Guangzhou. The abatement of fossil fuel combustion emissions and construction dust will have a significant beneficial effect on dust reduction.

  4. Research on flux of dry atmospheric falling dust and its characterization in a subtropical city, Guangzhou, South China

    PubMed Central

    Zhao, Jinping; Song, Jianzhong; Ma, Shexia; Sheng, Guoying; Fu, Jiamo

    2010-01-01

    Guangzhou is the central city in the Pearl River Delta (PRD), China, and is one of the most polluted cities in the world. To characterize the ambient falling dust pollution, two typical sampling sites: urban (Wushan) and suburban (University Town) areas in Guangzhou city were chosen for falling dust collection over 1 year at time intervals of 1 or 2 months. The flux of dry deposition was calculated. In addition, mineral composition and morphology of atmospheric falling dust were studied by X-ray diffraction, scanning electron microscopy, and microscopic observation. The results revealed that the dust flux in Guangzhou city was 3.34–3.78 g/(m2 month) during the study period. The main minerals in the dust were quartz, illite, calcite, kaolinite, gypsum, plagioclase, dolomite, and amorphous matter. The morphological types included grained and flaky individual minerals, chain-like aggregates, spherical flying beads, and irregular aggregates, with the chain-like and spherical aggregates indicators of industrial ash. The major dusts were derived from industrial and construction activities. The gypsum present in the dust collected in winter season was not only derived from cement dust but may also have originated from the reaction of calcic material with sulfuric acids resulting from photooxidation of SOx and NOx, which confirmed serious air pollution due to SOx and NOx in Guangzhou. The abatement of fossil fuel combustion emissions and construction dust will have a significant beneficial effect on dust reduction. PMID:20700381

  5. Deposition Rate and Size Distribution of Volcanic Ash

    NASA Astrophysics Data System (ADS)

    Hikida, M.

    2006-12-01

    Sakurajima Volcano has been in violent activity since 1955 and erupting large amount of volcanic ash and stones from the crater. Volcanic fallouts have caused damages to the agricaltural products in the area and denuded the mountainside of vegitation. Deposited ash and stones on the mountainside has also caused hazardrous debris flows in the rivers. Therefore, it is necessary to know the deposition rate of the fallouts in prediction of debris flow. Due to the violent volcanic activity, however, it is prohibited to enter within two kilometers of the crater, making it impossible to measure the depth of deposited fallouts in the area. Theoretical study on deposition rate of volcanic fallouts should be needed to estimate the amount of fallouts in the upstream area. At first, motion of a particle erupted from the crater into the air was computed to examine its trajectory. From the simulation of the trajectory, a particle was assumed to fall at its terminal veloctity, and theoretical equation which give the deposition rate of volcanic ash and the distribution of deposited ash were obtained. In the derivation of these equations, the probability density functions of eruption column height, the terminal velocity of the erupted particles and the wind velocity were introduced. The computed values of amount of deposited ash show good agreement with the data taken from 93 collection points around Sakurajima Volcano. The annual amount of erupted volcanic ash was estimated to be about thirteen millions tons. The sample of deposited fallouts were taken to analize the size distribution. The data was also used to check the applicability of the theory presented.

  6. Control of Toxic Chemicals in Puget Sound, Phase 3: Study of Atmospheric Deposition of Air Toxics to the Surface of Puget Sound

    SciTech Connect

    Brandenberger, Jill M.; Louchouarn, Patrick; Kuo, Li-Jung; Crecelius, Eric A.; Cullinan, Valerie I.; Gill, Gary A.; Garland, Charity R.; Williamson, J. B.; Dhammapala, R.

    2010-07-05

    The results of the Phase 1 Toxics Loading study suggested that runoff from the land surface and atmospheric deposition directly to marine waters have resulted in considerable loads of contaminants to Puget Sound (Hart Crowser et al. 2007). The limited data available for atmospheric deposition fluxes throughout Puget Sound was recognized as a significant data gap. Therefore, this study provided more recent or first reported atmospheric deposition fluxes of PAHs, PBDEs, and select trace elements for Puget Sound. Samples representing bulk atmospheric deposition were collected during 2008 and 2009 at seven stations around Puget Sound spanning from Padilla Bay south to Nisqually River including Hood Canal and the Straits of Juan de Fuca. Revised annual loading estimates for atmospheric deposition to the waters of Puget Sound were calculated for each of the toxics and demonstrated an overall decrease in the atmospheric loading estimates except for polybrominated diphenyl ethers (PBDEs) and total mercury (THg). The median atmospheric deposition flux of total PBDE (7.0 ng/m2/d) was higher than that of the Hart Crowser (2007) Phase 1 estimate (2.0 ng/m2/d). The THg was not significantly different from the original estimates. The median atmospheric deposition flux for pyrogenic PAHs (34.2 ng/m2/d; without TCB) shows a relatively narrow range across all stations (interquartile range: 21.2- 61.1 ng/m2/d) and shows no influence of season. The highest median fluxes for all parameters were measured at the industrial location in Tacoma and the lowest were recorded at the rural sites in Hood Canal and Sequim Bay. Finally, a semi-quantitative apportionment study permitted a first-order characterization of source inputs to the atmosphere of the Puget Sound. Both biomarker ratios and a principal component analysis confirmed regional data from the Puget Sound and Straits of Georgia region and pointed to the predominance of biomass and fossil fuel (mostly liquid petroleum products such

  7. Pesticides in western Canadian mountain air and soil.

    PubMed

    Daly, Gillian L; Lei, Ying D; Teixeira, Camilla; Muir, Derek C G; Wania, Frank

    2007-09-01

    The distribution of organochlorine pesticides (OCP; in past and current use) in the mountains of western Canada was determined by sampling air, soil, and lichen along three elevational transects in 2003-2004. Two transects west of the Continental Divide were located in Mount Revelstoke and Yoho National Park, while the Observation Peak transect in Banff National Park is east of the divide. XAD-based passive air samplers, yielding annually averaged air concentrations, were deployed, and soils were collected at all 22 sampling sites, whereas lichen were only sampled in Revelstoke. Back trajectory analysis showed limited air mass transport from the Prairies to the east, but a high frequency of air arriving from the southwest, which includes agricultural regions in British Columbia and Washington State. Endosulfan, dieldrin, and a-hexachlorocyclohexane were the most prevalent OCPs in air and soil; hexachlorobenzene was only abundant in air; chlorothalonil, dacthal, and pentachloronitrobenzene were also consistently present. OCP air concentrations were similar across the three transects, suggesting efficient atmospheric mixing on a local and regional scale. Soil concentrations and soil/air concentration ratios of many OCPs were significantly higher west of the Continental Divide. The soil and lichen concentrations of most OCPs increased with altitude in Revelstoke, and displayed maxima at intermediate elevations at Yoho and Observation Peak. These distribution patterns can be understood as being determined by the balance between atmospheric deposition to, and retention within, the soils. Higher deposition, due to more precipitation falling at lower temperatures, likely occurs west of the divide and at higher elevations. Higher retention, due to higher soil organic matter content, is believed to occur in soils below the tree line. Highest pesticide concentrations are thus found intemperate mountain soils that are rich in organic matter and receive large amounts of cold

  8. Fall prevention in hospitals: an integrative review.

    PubMed

    Spoelstra, Sandra L; Given, Barbara A; Given, Charles W

    2012-02-01

    This article summarizes research and draws overall conclusions from the body of literature on fall prevention interventions to provide nurse administrators with a basis for developing evidence-based fall prevention programs in the hospital setting. Data are obtained from published studies. Thirteen articles are retrieved that focused on fall interventions in the hospital setting. An analysis is performed based on levels of evidence using an integrative review process. Multifactoral fall prevention intervention programs that included fall-risk assessments, door/bed/patient fall-risk alerts, environmental and equipment modifications, staff and patient safety education, medication management targeted to specific types, and additional assistance with transfer and toileting demonstrate reduction in both falls and fall injuries in hospitalized patients. Hospitals need to reduce falls by using multifactoral fall prevention programs using evidence-based interventions to reduce falls and injuries.

  9. Fall Enrollment Report: University of Hawaii, Community Colleges, Fall 1981.

    ERIC Educational Resources Information Center

    Hawaii Univ., Honolulu. Office of Institutional Research and Analysis.

    Data are presented on a series of tables summarizing enrollment trends and the academic and personal characteristics of the 20,087 regular students enrolled in credit programs at six University of Hawaii community colleges during Fall, 1981. The tables cover: (1) headcount enrollment in regular credit and special programs; (2) headcount enrollment…

  10. Applications, Acceptances and Registrations, Fall 1975-Fall 1979.

    ERIC Educational Resources Information Center

    Hawaii Univ., Honolulu. Office of Institutional Research and Analysis.

    Patterns in student progression from application to acceptance and registration were analyzed for the fall semesters from 1975 to 1979 at six Hawaii community colleges. The data, compiled from the Coordinated Admissions Program Information System and from the Student Information System, indicate, with regard to applications, that: (1) a total of…

  11. BURDEN FALLS ROADLESS AREA, ILLINOIS.

    USGS Publications Warehouse

    Klasner, John S.; Thompson, Robert M.

    1984-01-01

    The Burden Falls Roadless Area lies in the Shawnee National Forest of southern Illinois, about 5 mi west of the western edge of the Illinois-Kentucky fluorspar district. Geologic mapping and geochemical surveys indicate that the area has little promise for the occurrence of fluorspar and associated minerals; other special studies also indicate little promise for oil and gas and construction materials. Traces of gold and silver were detected in some geochemical samples but follow-up studies indicate little promise for the occurrence of resources of these metals within the Burden Falls Roadless Area.

  12. APPLICATION OF A NEW LAND-SURFACE, DRY DEPOSITION, AND PBL MODEL IN THE MODELS-3 COMMUNITY MULTI-SCALE AIR QUALITY (CMAQ) MODEL SYSTEM

    EPA Science Inventory

    Like most air quality modeling systems, CMAQ divides the treatment of meteorological and chemical/transport processes into separate models run sequentially. A potential drawback to this approach is that it creates the illusion that these processes are minimally interdependent an...

  13. [Violence Profiles for Fall Programming.

    ERIC Educational Resources Information Center

    National Citizens Committee for Broadcasting, Washington, DC.

    This document presented by the National Citizens' Committee for Broadcasting at a 1976 press conference provides an assortment of materials concerned with violence in television. Among the materials included are "Who Sponsors the New Fall Violence?" by Nicholas Johnson, a description of and rationale for the study of advertisers who sponsor…

  14. Fall 1984 Community Services Study.

    ERIC Educational Resources Information Center

    Weeks, Ann A.

    In fall 1984, students who enrolled in credit-free courses at Dutchess Community College (DCC) were asked to provide demographic information as part of their registration process. Approximately 2,000 students, from almost all of the credit-free courses offered both on-campus and at off-campus sites, completed the student data form. Findings…

  15. [A study on fall accident].

    PubMed

    Lee, H S; Kim, M J

    1997-01-01

    The study was conducted from November 1995 to May 1996 at the one general hospital in Seoul. The total subjects of this study were 412 patients who have the experience of fall accident, among them 31 was who have fallen during hospitalization and 381 was who visited emergency room and out patient clinic. The purposes of this study were to determine the characteristics, risk factors and results of fall accident and to suggest the nursing strategies for prevention of fall. Data were collected by reviewing the medical records and interviewing with the fallers and their family members. For data analysis spss/pc+ program was utilized for descriptive statistics, adjusted standardized X2-test. The results of this study were as follows: 1) Total subjects were 412 fallers, of which 245 (59.5%) were men and 167 (40.5%) were women. Age were 0-14 years 79 (19.2%), 15-44 years 125 (30.4%), 45-64 years 104 (25.2%), over 65 years 104 (25.2%). 2) There was significant association between age and the sexes (X2 = 39.17, P = 0.00). 3) There was significant association between age and history of falls (X2 = 44.41, P = .00). And history of falls in the elderly was significantly associated with falls. 4) There was significant association with age and medical diagnosis (X2 = 140.66, P = .00), chief medical diagnosis were hypertension (34), diabetes mellitus (22), arthritis (11), stroke (8), fracture (7), pulmonary tuberculosis (6), dementia (5) and cataract (5). 5) There was significant association between age and intrinsic factors: cognitive impairment, mobility impairment, insomnia, emotional problems, urinary difficulty, visual impairments, hearing impairments, use of drugs (sedatives, antihypertensive drugs, diuretics, antidepressants) (P < 0.05). But there was no significant association between age and dizziness (X2 = 2.87, P = .41). 6) 15.3% of total fallers were drunken state when they were fallen. 7) Environmental factors of fall accident were unusual posture (50.9%), slips (35

  16. Fellows Celebrated at Fall Meeting

    NASA Astrophysics Data System (ADS)

    2010-12-01

    The 2010 AGU Fellows will be presented during the Fall Meeting Honors Tribute in San Francisco, Calif. The formal ceremony will be held on Wednesday, 15 December 2010. President-Elect Carol Finn will introduce each Fellow and read a brief statement of the achievements for which each has been selected.

  17. Fellows celebrated at Fall Meeting

    NASA Astrophysics Data System (ADS)

    2011-11-01

    The 2011 AGU Fellows will be presented during the Fall Meeting Honors Tribute in San Francisco, Calif. The formal ceremony will be held on Wednesday, 14 December 2011, during which President-Elect Carol Finn will introduce each Fellow and read a brief statement of the achievements for which each has been selected.

  18. Fellows celebrated at Fall Meeting

    NASA Astrophysics Data System (ADS)

    2012-11-01

    The 2012 AGU Fellows will be presented during the Fall Meeting Honors Tribute in San Francisco, Calif. The formal ceremony will be held on Wednesday, 5 December 2012, during which President-elect Carol Finn will introduce each Fellow and read a brief statement of the achievements for which each has been selected.

  19. Fall 1972 University Racial Census.

    ERIC Educational Resources Information Center

    Brooks, Glenwood C., Jr.; Sedlacek, William E.

    This document reports the results of the fall 1972 racial census at the University of Maryland. Only new freshmen, transfer students, and readmitted students filled out the racial census cards. All returning students constituted the data base of the student body. By adding new and deleting old racial census cards, counts could be made. Results of…

  20. Fall Armyworm in the Southeast

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two separate experiments testing fall armyworm (Spodoptera frugiperda) migration patterns were set up in the southeastern U.S. in 2012. Previous results showed that moths from progeny of overwintering populations from south Texas were found west of the Chattahoochee-Flint-Apalachicola river basin, ...

  1. Student Transfer Matrix, Fall 1992.

    ERIC Educational Resources Information Center

    Oklahoma State Regents for Higher Education, Oklahoma City.

    Comprised primarily of data matrices, this report provides information on students transferring from Oklahoma public and private post-secondary institutions to other public and private post-secondary institutions in the state in fall 1992. The report consists of nine sections. Section I provides an aggregate flow of all students in the state,…

  2. Terminal velocity of a shuttlecock in vertical fall

    NASA Astrophysics Data System (ADS)

    Peastrel, Mark; Lynch, Rosemary; Armenti, Angelo

    1980-07-01

    We have performed a straightforward vertical fall experiment for a case where the effects of air resistance are important and directly measurable. Using a commonly available badminton shuttlecock, a tape measure, and a millisecond timer, the times required for the shuttlecock to fall given distances (up to almost ten meters) were accurately measured. The experiment was performed in an open stairwell. The experimental data was compared to the predictions of several models. The best fit was obtained with the model which assumes a resistive force quadratic in the instantaneous speed of the falling object. This model was fitted to the experimental data enabling us to predict the terminal velocity of the shuttlecock (6.80 m/sec). The results indicate that, starting from rest, the vertically falling shuttlecock achieves 99% of its terminal velocity in 1.84 sec, after falling 9.2 m. The relative ease in collecting the data, as well as the excellent agreement with theory, make this an ideal experiment for use in physics courses at a variety of levels.

  3. A Breath of Fresh Air

    ERIC Educational Resources Information Center

    Belew, Rachel

    2011-01-01

    One of the most important aspects of a healthy school--and one that, unfortunately, often falls by the wayside--is indoor air quality. The U.S. Government Accountability Office estimates that more than 15,000 schools nationwide report suffering from poor indoor air quality. According to the U.S. Environmental Protection Agency, schools with poor…

  4. Analysis of the Clean Air Act Amendments of 1990: A forecast of the electric utility industry response to Title IV, Acid Deposition Control

    SciTech Connect

    Molburg, J.C.; Fox, J.A.; Pandola, G.; Cilek, C.M.

    1991-10-01

    The Clean Air Act Amendments of 1990 incorporate, for the first time, provisions aimed specifically at the control of acid rain. These provisions restrict emissions of sulfur dioxide (SO[sub 2]) and oxides of nitrogen (NO[sub x]) from electric power generating stations. The restrictions on SO[sub 2] take the form of an overall cap on the aggregate emissions from major generating plants, allowing substantial flexibility in the industry's response to those restrictions. This report discusses one response scenario through the year 2030 that was examined through a simulation of the utility industry based on assumptions consistent with characterizations used in the National Energy Strategy reference case. It also makes projections of emissions that would result from the use of existing and new capacity and of the associated additional costs of meeting demand subject to the emission limitations imposed by the Clean Air Act. Fuel-use effects, including coal-market shifts, consistent with the response scenario are also described. These results, while dependent on specific assumptions for this scenario, provide insight into the general character of the likely utility industry response to Title IV.

  5. Analysis of the Clean Air Act Amendments of 1990: A forecast of the electric utility industry response to Title IV, Acid Deposition Control

    SciTech Connect

    Molburg, J.C.; Fox, J.A.; Pandola, G.; Cilek, C.M.

    1991-10-01

    The Clean Air Act Amendments of 1990 incorporate, for the first time, provisions aimed specifically at the control of acid rain. These provisions restrict emissions of sulfur dioxide (SO{sub 2}) and oxides of nitrogen (NO{sub x}) from electric power generating stations. The restrictions on SO{sub 2} take the form of an overall cap on the aggregate emissions from major generating plants, allowing substantial flexibility in the industry`s response to those restrictions. This report discusses one response scenario through the year 2030 that was examined through a simulation of the utility industry based on assumptions consistent with characterizations used in the National Energy Strategy reference case. It also makes projections of emissions that would result from the use of existing and new capacity and of the associated additional costs of meeting demand subject to the emission limitations imposed by the Clean Air Act. Fuel-use effects, including coal-market shifts, consistent with the response scenario are also described. These results, while dependent on specific assumptions for this scenario, provide insight into the general character of the likely utility industry response to Title IV.

  6. Simple fabrication of air-stable black phosphorus heterostructures with large-area hBN sheets grown by chemical vapor deposition method

    NASA Astrophysics Data System (ADS)

    Sinha, Sapna; Takabayashi, Yuya; Shinohara, Hisanori; Kitaura, Ryo

    2016-09-01

    We have developed a facile and general method to passivate thin black phosphorus (BP) flakes with large-area high-quality monolayer hexagonal boron nitride (hBN) sheets grown by the chemical vapor deposition (CVD) method. In spite of the one-atom-thick structure, the high-quality CVD-grown monolayer hBN has proven to be useful to prevent the degradation of thin BP flakes exfoliated on substrates. Mechanically exfoliated BP flakes prepared on a Si substrate are covered by the monolayer hBN sheet to preserve (otherwise unstable) atomic layered BP flakes from degradation. The present technique can generally be applied to fabricating BP-based electronic devices with much easiness.

  7. Unravelling the magmatic processes behind zoned fall units on Ascension Island, South Atlantic

    NASA Astrophysics Data System (ADS)

    Chamberlain, K. J.; Barclay, J.; Preece, K.; Brown, R. J.; Davidson, J.

    2015-12-01

    Ascension Island, an isolated composite volcano in the south Atlantic, has a wide spectrum of explosive and effusive deposits. Eruptions on the island have produced ash and pumice fall deposits, ignimbrites, scoria cones, lava flows and lava domes, which vary in composition from basalt to rhyolite. We report, for the first time, the presence of multiple, zoned pumice fall deposits. These deposits grade upwards (stepwise or gradationally) from pumice to scoria. We present detailed observations of two key deposits which typify the range in zonation observed in the unusual fall units. Forensic examination of these deposits and their petrological and geochemical characteristics provide critical information about the interactions and processes behind the wide spectrum of magma compositions and past eruptive behaviour on Ascension Island. The first deposit changes gradationally from fayalite-bearing trachytic pumice fall (61.1 wt.% SiO2) at the base, to basaltic trachy-andesite scoria fall (54.5 wt.% SiO2) at the top. The second deposit is more complex. It contains mingled pumice-scoria clasts, has a rapid transition from pumice to scoria and no intermediate clasts were observed. New analyses of H2O, CO2 and key trace elements within melt inclusions combined with systematic whole rock and phenocryst analyses enable us to probe the relationship of these co-erupted magmas to other deposits on the island. This has yielded insights into the magma plumbing system; and improved understanding of the roles that fractional crystallisation and magma mixing play in generating the range in compositions observed at this unique ocean island volcano.

  8. Modification of ozone deposition and I2 emissions at the air-aqueous interface by dissolved organic carbon of marine origin.

    PubMed

    Shaw, Marvin D; Carpenter, Lucy J

    2013-10-01

    The reaction between gaseous ozone (O3) and aqueous iodide (I(-)) at the surface microlayer (SML) is believed to be a major chemical contributor to the oceanic dry deposition of O3 over open ocean waters and has also recently been shown to produce environmentally significant quantities of gaseous molecular iodine (I2). Here we investigate how this reaction is affected by the presence of dissolved organic carbon (DOC) of marine origin, using a heterogeneous flow reactor and detection of gaseous I2 by solvent trapping and UV/vis spectroscopy. Ozone deposition measurements over coastal seawater implied an O3 reactivity (λ) toward coastal marine DOC of ∼500 (420-580) s(-1), 2-5 times higher than that toward iodide at typical ocean concentrations (∼0.5-1 × 10(-7) M). We added varying amounts of highly concentrated DOC extracted from coastal seawater to I(-) solutions (1 × 10(-5) M) such that the relative reactivities of DOC and I(-) toward O3 (λDOC/λI) were in the expected range for natural seawater. The evolution of gaseous I2 and the loss of aqueous I(-) both reduced as DOC concentrations increased, with an overall suppression of I2 emissions of about a factor of 2 under conditions of λDOC/λI representative of open ocean waters (0.5-1). A kinetic model of the SML suggested that neither competition of DOC with I(-) for reaction with interfacial O3, nor direct loss of I2 and hypoiodous acid (HOI) through reaction with increasing quantities of DOC, can fully explain these results. We conclude that the suppression of I2 emissions by DOC is largely a physical effect arising from a decrease in the net transfer of I2 from the aqueous to gas phase, as suggested by recent laboratory studies.

  9. Inertial sensing-based pre-impact detection of falls involving near-fall scenarios.

    PubMed

    Lee, Jung Keun; Robinovitch, Stephen N; Park, Edward J

    2015-03-01

    Although near-falls (or recoverable imbalances) are common episodes for many older adults, they have received a little attention and were not considered in the previous laboratory-based fall assessments. Hence, this paper addresses near-fall scenarios in addition to the typical falls and activities of daily living (ADLs). First, a novel vertical velocity-based pre-impact fall detection method using a wearable inertial sensor is proposed. Second, to investigate the effect of near-fall conditions on the detection performance and feasibility of the vertical velocity as a fall detection parameter, the detection performance of the proposed method (Method 1) is evaluated by comparing it to that of an acceleration-based method (Method 2) for the following two different discrimination cases: falls versus ADLs (i.e., excluding near-falls) and falls versus non-falls (i.e., including near-falls). Our experiment results show that both methods produce similar accuracies for the fall versus ADL detection case; however, Method 1 exhibits a much higher accuracy than Method 2 for the fall versus non-fall detection case. This result demonstrates the superiority of the vertical velocity over the peak acceleration as a fall detection parameter when the near-fall conditions are included in the non-fall category, in addition to its capability of detecting pre-impact falls.

  10. The Grainsize Characteristics of Coignimbrite Deposits

    NASA Astrophysics Data System (ADS)

    Engwell, Samantha; Eychenne, Julia

    2015-04-01

    Due to their long atmospheric residence time, identifying the source and understanding the dispersion processes of fine-grained ash is of great importance when considering volcanic hazard and risk. An exceptionally efficient mechanism to supply large volumes of fine-grained ash to the stratosphere is the formation of co-ignimbrite plumes. Such plumes form as air is entrained at the top of propagating pyroclastic density currents, allowing a neutrally buoyant package of gas and ash to loft to high altitudes, consequently dispersing over large areas. The study of ash deposits on land and in deep sea cores has demonstrated that such events have played a major role during ignimbrite-forming eruptions, including the Tambora 1815, the Minoan (Santorini), the Campanian Ignimbrite, and the Younger Toba Tuff eruptions, as well as during more recent, pyroclastic flow-forming, intermediate sized eruptions (Vulcanian to Plinian in style), e.g. Mount St. Helens 1980, Fugen-dake (Unzen) 1991, Pinatubo 1991, Montserrat 1997 and Tungurahua 2006 eruptions. Published, as well as new results from the study of co-ignimbrite deposits, show that co-ignimbrite plumes can rise to high altitudes into the atmosphere (the co-ignimbrite plumes from the May 18, 1980 Mount St Helens blast and the Campanian Ignimbrite eruptions reached 30 - 35 km a.s.l,), potentially distribute enormous volumes of ash (the 75 ka Toba eruption and the Minoan eruption of Santorini settled >800 km3 and >25 km3 of co-ignimbrite ash, respectively), and contribute much of the ash to very large (60±6 vol% of the Campanian fallout deposit 130 to 900 km from vent), as well as intermediate size (up to 58 wt% and 52 wt% in the 2006 Tungurahua and May 18, 1980 Mount St. Helens fallout deposits, respectively) explosive eruptions. Comparison of new data with those from the published record shows that co-ignimbrite deposits are strikingly similar, regardless of eruption conditions, and have distinct grain size characteristics

  11. Validating a multifactorial falls risk assessment.

    PubMed

    James, Michele B; Kimmons, Nancy J; Schasberger, Britta; Lefkowitz, Abigail

    2014-01-01

    Reducing risk of falls has been identified as a national safety goal by The Joint Commission (TJC). The purpose was to determine if the total score on the multifactorial Falls Risk Assessment accurately identifies the risk of falls in a homebound client. In addition, the study examined if any individual item had a higher predictive power with the incidence of falls. One hundred clients (> 65 years old) who sustained an avoidable fall during a home care episode of care, plus 25 home care clients in the same age range and time period, who did not fall. A retrospective chart review, including Falls Risk Assessment (FRA) performed at start of care, demographic information, specific physical therapy (PT) evaluation, and visit notes if necessary to determine if the fall met the inclusion criteria. Scores for each individual area of the assessment were collected for statistical analysis. Data were analyzed by a biostatistician using simple linear regression, t-tests, and regression of variable combinations. The total score on the multifactorial risk assessment tool was shown to have a strong relationship with incidence of falls. The average scores of individuals who fell after assessment were significantly higher than those of individuals who did not fall. No single factors were found to be highly predictive. A single approach to decreasing falls is likely to be less effective than a multipronged approach. Caregivers and providers are advised to consider the entirety of the falls risk and direct comprehensive interventions to address the multiple factors that lead to falls.

  12. Late Cenozoic Reverse Faulting in the Fall Zone, Southeastern Virginia.

    PubMed

    Berquist Jr; Bailey

    1999-11-01

    A set of en-echelon reverse faults cut Paleozoic metamorphosed igneous rocks of the Piedmont and overlying late Cenozoic sediments at the Old Hickory Heavy Mineral Deposit in the Fall Zone of southeastern Virginia. Diorite of the eastern Slate Belt was faulted over nearshore to shore-face deposits of the Pliocene Yorktown Formation. These NW-SE-striking faults experienced oblique dip-slip movement with a maximum displacement of up to 6 m on individual faults. Faults tip out along strike and are overlain by distinct cobble beds, suggesting that sediment deposition and faulting were contemporaneous. Deformation at Old Hickory may have been formed by reactivation of existing Paleozoic structures under a regionally extensive compressional stress field parallel to the modern one. PMID:10517887

  13. Late Cenozoic Reverse Faulting in the Fall Zone, Southeastern Virginia.

    PubMed

    Berquist Jr; Bailey

    1999-11-01

    A set of en-echelon reverse faults cut Paleozoic metamorphosed igneous rocks of the Piedmont and overlying late Cenozoic sediments at the Old Hickory Heavy Mineral Deposit in the Fall Zone of southeastern Virginia. Diorite of the eastern Slate Belt was faulted over nearshore to shore-face deposits of the Pliocene Yorktown Formation. These NW-SE-striking faults experienced oblique dip-slip movement with a maximum displacement of up to 6 m on individual faults. Faults tip out along strike and are overlain by distinct cobble beds, suggesting that sediment deposition and faulting were contemporaneous. Deformation at Old Hickory may have been formed by reactivation of existing Paleozoic structures under a regionally extensive compressional stress field parallel to the modern one.

  14. Transport of macromolecules and particles at target sites for deposition of air pollutants. Report for 1 August 1983-31 July 1985

    SciTech Connect

    Crocker, T.T.; Bhalla, D.K.

    1986-01-01

    The study analyzed rats' nasal, tracheal and bronchoalveolar epithelial permeability to macromolecules after they were exposed, in 2- or 4-hour periods of rest or exercise, to ozone (O/sub 3/)(0.6, 0.8 or 2 ppm), nitrogen dioxide (NO/sub 2/)(2.5, 6 or 12 ppm) or formaldehyde (10 ppm). Exercise was performed on a treadmill operated at a speed that led to a 2-fold increase in oxygen consumption. Histopathologic and electron-microscopic cytochemical and autoradiographic studies were performed to identify the structural aspects of mucosal response. Results indicate that different air pollutants affect different sites in the respiratory tract with respect to epithelial permeability to macromolecules.

  15. Becquerel Crater Deposit

    NASA Technical Reports Server (NTRS)

    2002-01-01

    (Released 28 May 2002) The finely layered deposit in Becquerel crater, seen in the center of this THEMIS image, is slowly being eroded away by the action of windblown sand. Dark sand from a source north of the bright deposit is collecting along its northern edge, forming impressive barchan style dunes. These vaguely boomerang-shaped dunes form with their two points extending in the downwind direction, demonstrating that the winds capable of moving sand grains come from the north. Grains that leave the dunes climb the eroding stair-stepped layers, collecting along the cliff faces before reaching the crest of the deposit. Once there, the sand grains are unimpeded and continue down the south side of the deposit without any significant accumulation until they fall off the steep cliffs of the southern margin. The boat-hull shaped mounds and ridges of bright material called yardangs form in response to the scouring action of the migrating sand. To the west, the deposit has thinned enough that the barchan dunes extend well into the deeply eroded north-south trending canyons. Sand that reaches the south side collects and reforms barchan dunes with the same orientation as those on the north side of the deposit. Note the abrupt transition between the bright material and the dark crater floor on the southern margin. Steep cliffs are present with no indication of rubble from the obvious erosion that produced them. The lack of debris at the base of the cliffs is evidence that the bright material is readily broken up into particles that can be transported away by the wind. The geological processes that are destroying the Becquerel crater deposit appear active today. But it is also possible that they are dormant, awaiting a particular set of climatic conditions that produces the right winds and perhaps even temperatures to allow the erosion to continue.

  16. Three-dimensional model for aerosol transport and deposition in expanding and contracting alveoli.

    PubMed

    Balásházy, Imre; Hofmann, Werner; Farkas, Arpád; Madas, Balázs G

    2008-04-01

    Particle transport and deposition within a model alveolus, represented by a rhythmically expanding and contracting hemisphere, was modeled by a three-dimensional analytical model for the time-dependent air velocity field as a superposition of uniform and radial flow components, satisfying both the mass and momentum conservation equations. Trajectories of particles entrained in the airflow were calculated by a numerical particle trajectory code to compute simultaneously deposition by inertial impaction, gravitational sedimentation, Brownian diffusion, and interception. Five different orientations of the orifice of the alveolus relative to the direction of gravity were selected. Deposition was calculated for particles from 1 nm to 10 microm, for 3 breathing conditions, and for 5 different entrance times relative to the onset of inspiration. For the analyzed cases, the spatial orientation of the orifice of an alveolus has practically no effect on deposition for particles below about 0.1 microm, where deposition is dominated by Brownian motion. Above about 1 microm, where deposition is governed primarily by gravitational settling, deposition can vary from 0 to 100%, depending on the spatial orientation, while deposition of particles 0.1-1 microm falls between these two extreme cases. Due to the isotropic nature of Brownian motion, deposition of the 10-nm particles is practically uniform for all spatial orientations. However, for larger particles, deposition can be quite inhomogeneous, consistent with the direction of gravity. While nearly all particles are exhaled during the successive expiration phase, there are a few cases where particles still leave the alveolus even after many breathing cycles.

  17. After a fall in the hospital

    MedlinePlus

    ... do not see patients fall. But falls require attention right away to lessen the risk of injury. ... patient's breathing, pulse, and blood pressure. If the patient is ... a hospital emergency code and start CPR. Check for injury, such ...

  18. High-mobility and air-stable single-layer WS2 field-effect transistors sandwiched between chemical vapor deposition-grown hexagonal BN films.

    PubMed

    Iqbal, M Waqas; Iqbal, M Zahir; Khan, M Farooq; Shehzad, M Arslan; Seo, Yongho; Park, Jong Hyun; Hwang, Chanyong; Eom, Jonghwa

    2015-01-01

    An emerging electronic material as one of transition metal dichalcogenides (TMDCs), tungsten disulfide (WS2) can be exfoliated as an atomically thin layer and can compensate for the drawback of graphene originating from a gapless band structure. A direct bandgap, which is obtainable in single-layer WS2, is an attractive characteristic for developing optoelectronic devices, as well as field-effect transistors. However, its relatively low mobility and electrical characteristics susceptible to environments remain obstacles for the use of device materials. Here, we demonstrate remarkable improvement in the electrical characteristics of single-layer WS2 field-effect transistor (SL-WS2 FET) using chemical vapor deposition (CVD)-grown hexagonal BN (h-BN). SL-WS2 FET sandwiched between CVD-grown h-BN films shows unprecedented high mobility of 214 cm(2)/Vs at room temperature. The mobility of a SL-WS2 FET has been found to be 486 cm(2)/Vs at 5 K. The ON/OFF ratio of output current is ~10(7) at room temperature. Apart from an ideal substrate for WS2 FET, CVD-grown h-BN film also provides a protection layer against unwanted influence by gas environments. The h-BN/SL-WS2/h-BN sandwich structure offers a way to develop high-quality durable single-layer TMDCs electronic devices. PMID:26030008

  19. A micro-scale hot wire anemometer based on low stress (Ni/W) multi-layers deposited on nano-crystalline diamond for air flow sensing

    NASA Astrophysics Data System (ADS)

    Talbi, A.; Gimeno, L.; Gerbedoen, J.-C.; Viard, R.; Soltani, A.; Mortet, V.; Preobrazhensky, V.; Merlen, A.; Pernod, P.

    2015-12-01

    A linear array of microscale thermal anemometers has been designed, fabricated and characterized. The sensitive element consists of a self-compensated-stress multilayer (Ni/W) patterned to form a wire with length, width, and thickness close to 200 μm, 5 μm and 2 μm respectively. The wire is deposited and supported by prongs made of nano-crystalline diamond (NCD) of about 2 μm in thickness. Due to its high Young’s modulus, NCD allows a very high mechanical toughness without the need for thicker support for the hot wire. Also, depending on grain size, the NCD is able to present thermal conductivity smaller than 10 W mK-1, providing good thermal insulation from the substrate and less conductive end losses to the prongs. The sensor was characterized experimentally. Its electrical and thermal properties were obtained first in the absence of fluid flow. The results confirm the effectiveness of thermal insulation and the mechanical robustness of the structure. The fluidic characterizations were performed and analysed in the case of an airflow with velocities of up to 30 m s-1.

  20. Detecting Falling Snow from Space

    NASA Technical Reports Server (NTRS)

    Jackson, Gail Skofronick; Johnson, Ben; Munchak, Joe

    2012-01-01

    There is an increased interest in detecting and estimating the amount of falling snow reaching the Earth's surface in order to fully capture the atmospheric water cycle. An initial step toward global spaceborne falling snow algorithms includes determining the thresholds of detection for various active and passive sensor channel configurations, snow event cloud structures and microphysics, snowflake particle electromagnetic properties, and surface types. In this work, cloud resolving model simulations of a lake effect and synoptic snow event were used to determine the minimum amount of snow (threshold) that could be detected by the following instruments: the W -band radar of CloudSat, Global Precipitation Measurement (GPM) Dual-frequency Precipitation Radar (DPR) Ku and Ka band, and the GPM Microwave Imager (GMI) channels from 10 to 183 plus or minus 7 GHz. Eleven different snowflake shapes were used to compute radar reflectivities and passive brightness temperatures. Notable results include: (1) the W-Band radar has detection thresholds more than an order of magnitude lower than the future GPM sensors, (2) the cloud structure macrophysics influences the thresholds of detection for passive channels, (3) the snowflake microphysics plays a large role in the detection threshold for active and passive instruments, (4) with reasonable assumptions, "the passive 166 GHz channel has detection threshold values comparable to the GPM DPR Ku and Ka band radars with approximately 0.05 g per cubic meter detected at the surface, or an approximately 0.5-1 millimeter per hr. melted snow rate (equivalent to 0.5-2 centimeters per hr. solid fluffy snowflake rate). With detection levels of falling snow known, we can focus current and future retrieval efforts on detectable storms and concentrate advances on achievable results. We will also have an understanding of the light snowfall events missed by the sensors and not captured in the global estimates.

  1. The variability of meteoroid falling

    NASA Astrophysics Data System (ADS)

    Velasco Herrera, V. M.; Cordero, G.

    2016-10-01

    We analysed a historical catalogue of meteoroid falling during the last 400 years. We report here for the first time the synchronization between observed meteors and solar barycentric parameters in 19.6 and 13.2 years periodicities using a new multiple cross wavelet. The group of moderated number of meteors is distributed around the positive phase of the solar barycentric periodicity of 13.2 years. While the group of severe number of meteors are distributed on the positive phase of the solar barycentric periodicity of 19.6 years. These periodicities could be associated with Jupiter periodicities. So understanding the modulation of meteoroid falling is important for determining the falling patterns of these objects and for knowing when it is more likely to expect the entry of one of these objects into the Earth's atmosphere, because bodies falling onto the Earth can cause damage from minor impacts to mass-extinctions events. One of the most extreme events was the formation of the Chicxulub impact crater 65,000,000 years ago that caused one of the five major mass extinctions in the last 500,000,000 years. During the 20th and 21st centuries, a series of events demonstrated the importance of collisions between planets and small bodies (comets and asteroids), which included our own planet. In the case of the Earth, we can cite three examples: Tunguska, Curuça and Chelyabinsk. These events invite us to think that perhaps the occurrence of this phenomenon might be more common than we realize, but the lack of communication or people in the area where they happened prevents us from having a complete record. Modern man has not witnessed the impact of large asteroids or comets on our planet, but it has been observed on other planetary bodies. The most spectacular of these events was the collision of fragments of the comet Shoemaker-Levy 9 with Jupiter in 1994. The total energy of the 21 impacts on Jupiter's atmosphere was estimated as the equivalent of tens of millions of

  2. 29 CFR 1926.760 - Fall protection.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 8 2011-07-01 2011-07-01 false Fall protection. 1926.760 Section 1926.760 Labor... (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Steel Erection § 1926.760 Fall protection. (a... protection from fall hazards in accordance with paragraph (a)(1) of this section. (c) Controlled Decking...

  3. 29 CFR 1926.760 - Fall protection.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 8 2010-07-01 2010-07-01 false Fall protection. 1926.760 Section 1926.760 Labor... (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Steel Erection § 1926.760 Fall protection. (a... protection from fall hazards in accordance with paragraph (a)(1) of this section. (c) Controlled Decking...

  4. 29 CFR 1926.760 - Fall protection.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 8 2014-07-01 2014-07-01 false Fall protection. 1926.760 Section 1926.760 Labor... (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Steel Erection § 1926.760 Fall protection. (a... protection from fall hazards in accordance with paragraph (a)(1) of this section. (c) Controlled Decking...

  5. 29 CFR 1917.41 - House falls.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 7 2014-07-01 2014-07-01 false House falls. 1917.41 Section 1917.41 Labor Regulations...) MARINE TERMINALS Cargo Handling Gear and Equipment § 1917.41 House falls. (a) Span beams shall be secured... working with house fall blocks. (c) Designated employees shall inspect chains, links, shackles,...

  6. 29 CFR 1917.41 - House falls.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 7 2012-07-01 2012-07-01 false House falls. 1917.41 Section 1917.41 Labor Regulations...) MARINE TERMINALS Cargo Handling Gear and Equipment § 1917.41 House falls. (a) Span beams shall be secured... working with house fall blocks. (c) Designated employees shall inspect chains, links, shackles,...

  7. 29 CFR 1917.41 - House falls.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 7 2011-07-01 2011-07-01 false House falls. 1917.41 Section 1917.41 Labor Regulations...) MARINE TERMINALS Cargo Handling Gear and Equipment § 1917.41 House falls. (a) Span beams shall be secured... working with house fall blocks. (c) Designated employees shall inspect chains, links, shackles,...

  8. Imager displays free fall in stop action

    NASA Technical Reports Server (NTRS)

    Frazer, R. E.

    1981-01-01

    Microprocessor-controlled imaging system displays sequence of "frozen" images of free-falling object, using video cameras positioned along fall. Strobe lights flash as object passes each camera's viewfield. Sequence stored on video disk and displayed on television monitor is stop-action record of fall dynamics. With modification, system monitiors other high speed phenomena.

  9. Epidemiology of Falls in Older Age

    ERIC Educational Resources Information Center

    Peel, Nancye May

    2011-01-01

    Worldwide, falls among older people are a public health concern because of their frequency and adverse consequences in terms of morbidity, mortality, and quality of life, as well as their impact on health system services and costs. This epidemiological review outlines the public health burden of falls and fall-related injuries and the impact of…

  10. The interconnection of wet and dry deposition and the alteration of deposition budgets due to incorporation of new process understanding in regional models

    NASA Astrophysics Data System (ADS)

    Dennis, R. L.; Bash, J. O.; Foley, K. M.; Gilliam, R.; Pinder, R. W.

    2013-12-01

    Deposition is affected by the chemical and physical processes represented in the regional models as well as source strength. The overall production and loss budget (wet and dry deposition) is dynamically connected and adjusts internally to changes in process representation. In addition, the scrubbing of pollutants from the atmosphere by precipitation is one of several processes that remove pollutants, creating a coupling with the atmospheric aqueous and gas phase chemistry that can influence wet deposition rates in a nonlinear manner. We explore through model sensitivities with the regional Community Multiscale Air Quality (CMAQ) model the influence on wet and dry deposition, and the overall continental nitrogen budget, of changes in three process representations in the model: (1) incorporation of lightning generated NO, (2) improved representation of convective precipitation, and (3) replacement of the typical unidirectional dry deposition of NH3 with a state of the science representation of NH3 bi-directional air-surface exchange. Results of the sensitivity studies will be presented. (1) Incorporation of lightning generated NO significantly reduces a negative bias in summer wet nitrate deposition, but is sensitive to the choice of convective parameterization. (2) Use of a less active trigger of convective precipitation in the WRF meteorological model to reduce summertime precipitation over prediction bias reduces the generation of NO from lightning. It also reduces the wet deposition of nitrate and increases the dry deposition of oxidized nitrogen, as well as changing (reducing) the surface level exposure to ozone. Improvements in the convective precipitation processes also result in more non-precipitating clouds leading to an increase in SO4 production through the aqueous pathway resulting in improvements in summertime SO4 ambient aerosol estimates.(3) Incorporation of state of the science ammonia bi-directional air surface exchange affects both the dry

  11. 46 CFR 154.345 - Air locks.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... mechanically ventilated to make the pressure in the space greater than that in the air lock; and (2) Has a... when the pressure in the space falls to or below the pressure in the air lock. ... 46 Shipping 5 2013-10-01 2013-10-01 false Air locks. 154.345 Section 154.345 Shipping COAST...

  12. Swan falls instream flow study

    SciTech Connect

    Anglin, D.R.; Cummings, T.R.; Ecklund, A.E.

    1992-10-01

    The purpose of the Swan Falls Instream Flow Study was to define the relationship between streamflows and instream habitat for resident fish species and to assess the relative impact of several different hydrographs on resident fish habitat. Specific objectives included the following: (1) Conduct a literature search to compile life history, distribution, and habitat requirements for species of interest. Physical and hydrologic characteristics of the Snake River were also compiled. (2) Determine physical habitat versus discharge relationships and conduct habitat time series analysis for each species/lifestage using the Instream Flow Incremental Methodology (IFIM) developed by the U.S. Fish and Wildlife Service. (3) Examine the impacts on resident fish habitat of proposed hydrographs, including Swan Falls Agreement flows, relative to current conditions. (4) Characterize water quality conditions, including water temperature and dissolved oxygen, in the vicinity of the study area and determine the implications of those conditions for the resident species of interest. (5) Determine streamflows necessary to protect and maintain resident fish habitat in the study area.

  13. Estimation of the caesium-137 source term from the Fukushima Daiichi nuclear power plant using a consistent joint assimilation of air concentration and deposition observations

    NASA Astrophysics Data System (ADS)

    Winiarek, Victor; Bocquet, Marc; Duhanyan, Nora; Roustan, Yelva; Saunier, Olivier; Mathieu, Anne

    2014-01-01

    Inverse modelling techniques can be used to estimate the amount of radionuclides and the temporal profile of the source term released in the atmosphere during the accident of the Fukushima Daiichi nuclear power plant in March 2011. In Winiarek et al. (2012b), the lower bounds of the caesium-137 and iodine-131 source terms were estimated with such techniques, using activity concentration measurements. The importance of an objective assessment of prior errors (the observation errors and the background errors) was emphasised for a reliable inversion. In such critical context where the meteorological conditions can make the source term partly unobservable and where only a few observations are available, such prior estimation techniques are mandatory, the retrieved source term being very sensitive to this estimation. We propose to extend the use of these techniques to the estimation of prior errors when assimilating observations from several data sets. The aim is to compute an estimate of the caesium-137 source term jointly using all available data about this radionuclide, such as activity concentrations in the air, but also daily fallout measurements and total cumulated fallout measurements. It is crucial to properly and simultaneously estimate the background errors and the prior errors relative to each data set. A proper estimation of prior errors is also a necessary condition to reliably estimate the a posteriori uncertainty of the estimated source term. Using such techniques, we retrieve a total released quantity of caesium-137 in the interval 11.6-19.3 PBq with an estimated standard deviation range of 15-20% depending on the method and the data sets. The “blind” time intervals of the source term have also been strongly mitigated compared to the first estimations with only activity concentration data.

  14. Improvement in understanding the deposition of ambient dust particles on ECAM (environmental continuous air monitor) filters, reduction of the alpha-particle interference of radon progeny and other radioactive aerosols in different particle size ranges on filters, and development of ECAMs with increased sensitivity under dusty outdoor conditions.

    SciTech Connect

    Schery, Stephen D., Wasiolek, Piotr; Rodgers, John

    1999-06-01

    Improvement in understanding the deposition of ambient dust particles on ECAM (environmental continuous air monitor) filters, reduction of the alpha-particle interference of radon progeny and other radioactive aerosols in different particle size ranges on filters, and development of ECAMs with increased sensitivity under dusty outdoor conditions.

  15. Patient Engagement in Hospital Fall Prevention.

    PubMed

    Tzeng, Huey-Ming; Yin, Chang-Yi

    2015-01-01

    Injurious falls are the most prevalent in-hospital adverse event, and hospitalized patients are at a greater risk of falling than the general population. Patient engagement in hospital fall prevention could be a possible approach to reducing falls and fall-related injuries. To engage patients, bedside nursing staff must first understand the concept of patient centeredness and then incorporate patient centeredness in clinical practice. Clinicians should move from being experts to being enablers. To conceptualize the knowledge gaps identified, a conceptual model was developed to guide future research and quality improvement efforts in hospital settings. This model could be used as a guide to advance nursing leadership in hospital fall prevention via promoting patient engagement (e.g., developing patient-centered fall prevention interventions with patients' input).

  16. [Prevention programs of risk factors for falls].

    PubMed

    Kumagai, Shuzo; Sakita, Masahiro

    2014-10-01

    Approximately 17% of Japanese older people fall for a year. The femoral neck fractures with falls caused by various functional problems make them depress remarkably activities of daily living and quality of life. In risk factors for falls in old people, muscle weakness, balance and gait disorders particularly increases to falls. The major results from recent systematic reviews have indicated that interventions of exercise, multifactorial, environmental modification and gradual withdrawal of psychotropic medication in community-dwelling elderly people were effective for preventing falls. Regarding the older people in hospitals and sanatoriums, it appeared that comprehensive multifactorial interventions and vitamin D supplementation could be effective in falls rather than exercises intervention only. However, the short period of the exercise intervention may affect ineffectiveness in preventing falls.

  17. Prevalence of falls in elderly women

    PubMed Central

    Vitor, Priscila Regina Rorato; de Oliveira, Ana Carolina Kovaleski; Kohler, Renan; Winter, Gabriele Regiane; Rodacki, Cintia; Krause, Maressa Priscila

    2015-01-01

    OBJECTIVE: To verify prevalence of falls and fear of falling, and to compare functional fitness among elderly women fallers and non-fallers. METHODS: Seventy-eight elderly women participated in this study. Cases of falls and the fear of falling were self-reported by the elderly women, while the functional fitness was measured by a set of functional tests. Mean and standard deviation were used to describe the sample. Independent t-test was used to compare functional fitness between groups. RESULTS: The prevalence of falls in this sample was 32.4%. Among women fallers, 40% self-reported a high fear of falling. CONCLUSION: It is recommended that functional and resistance exercises are included in the preventive strategies for reducing risk factors for falls and its determinants in elderly women. Level of Evidence II, Prognostic-Prospective Study. PMID:26207095

  18. Transport and deposition of PAHs in East Asia using Regional Emission Inventory in ASia and Regional Air Quality Model for POP version

    NASA Astrophysics Data System (ADS)

    Inomata, Y.; Kajino, M.; Keiichi, S.; Ohara, T.; Kurokawa, J.; Hiromasa, U.; Tang, N.; Hayakawa, K.; Tsuyoshi, O.; Akimoto, H.

    2011-12-01

    We developed a new emission inventory for polycyclic aromatic hydrocarbons (9PAHs; fluorene, pyrene, benzo[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, benzo[g,h,i]perylene, and indeno[1,2,3-cd]pyrene) in ASia (Regional Emission inventory in Asia for POP version, REAS-POP) at 0.5x0.5 grid for the period from 2000 to 2005. By using the REAS-POP, spatial distributions of PAHs in East Asia were simulated by Regional Air Quality Model for POP version (RAQM-POP). In REAS-POP, estimated annual emission of 9PAHs in East Asia was increased from 7.61 Gg yr-1 in 2000 to 10.79 Gg yr-1 in 2005. The China is the dominant PAHs emission country in East Asia during this period. Area where considerable high emissions as well as rapid increase rate was found in the northern central region, North China Plain, Guizhou, Sichuan Basin, and North East in China. The contribution from various sources for PAHs emission was different by each country. In the developing country (China, Democratic People's Republic of Korea, Mongolia, and Russia), dominant sources of PAHs were domestic coal, domestic biofuel, and other transformation of coal including cokes production, although contribution from open biomass burning was relatively large in Russia and Mongol. In Japan and Taiwan, the road traffic source was identified as the major source for the 9PAHs emissions. At Beijing, China, simulated PAHs concentrations were quantitatively agreed with the measured concentrations during the period from 8 March to 26 May, 2005. In the case of Wajima, coastal site of the Sea of Japan in Japan, it was observed clear seasonal variation with high concentrations in winter and low concentrations in summer in 2005. The measured seasonal variations were also simulated well. Results with analysis by model simulation revealed that higher concentrations in winter were due to the high emission in China in winter and long-range transport from the Asian continent toward the Japanese

  19. Fall TIPS: strategies to promote adoption and use of a fall prevention toolkit.

    PubMed

    Dykes, Patricia C; Carroll, Diane L; Hurley, Ann; Gersh-Zaremski, Ronna; Kennedy, Ann; Kurowski, Jan; Tierney, Kim; Benoit, Angela; Chang, Frank; Lipsitz, Stuart; Pang, Justine; Tsurkova, Ruslana; Zuyov, Lyubov; Middleton, Blackford

    2009-11-14

    Patient falls are serious problems in hospitals. Risk factors for falls are well understood and nurses routinely assess for fall risk on all hospitalized patients. However, the link from nursing assessment of fall risk, to identification and communication of tailored interventions to prevent falls is yet to be established. The Fall TIPS (Tailoring Interventions for Patient Safety) Toolkit was developed to leverage existing practices and workflows and to employ information technology to improve fall prevention practices. The purpose of this paper is to describe the Fall TIPS Toolkit and to report on strategies used to drive adoption of the Toolkit in four acute care hospitals. Using the IHI "Framework for Spread" as a conceptual model, the research team describes the "spread" of the Fall TIPS Toolkit as means to integrate effective fall prevention practices into the workflow of interdisciplinary caregivers, patients and family members.

  20. Falling Barometer--Failing Behavior.

    ERIC Educational Resources Information Center

    Scagliotta, Edward G.

    1980-01-01

    Observations of 127 boys with behavior problems (ages 9 to 13) were made to study the correlation between air pressure and adverse behavior in the Ss. Results showed that, with each change in barometric pressure, there was an obvious change in the Ss' behavior. (PHR)

  1. New technologies transform Fall Meeting

    NASA Astrophysics Data System (ADS)

    O'Brien, Michael

    2012-02-01

    The 2011 Fall Meeting was transformed by the introduction of nine new technologies, most notably, a mobile app and the AGU ePoster system. With more than 11,000 downloads and 250,000 page views, the mobile app quickly replaced the program books for many attendees. Peter Petley of Durham University and blogger for the Landslide Blog said, "I have found that one of the challenges of attending AGU is being able to identify all of the sessions that are of interest, and then creating a schedule without carrying reams of paper." He continued, "I found that the mobile app has transformed my conference experience, providing a simple means to collate all of the sessions and to plan my day. As a result, I have found the meeting to be much more enjoyable and fulfilling."

  2. National Uranium Resource Evaluation, Klamath Falls Quadrangle, Oregon and California

    SciTech Connect

    Castor, S.B.; Berry, M.R.; Robins, J.W.

    1982-07-01

    The Klamath Falls Quadrangle, Oregon, was evaluated to identify and delineate areas favorable for uranium deposits according to criteria developed for the National Uranium Resource Evaluation. Surface radiometric reconnaissance and geochemical sampling were used for overall evaluation of the quadrangle. Detailed rock sampling, geologic mapping, and examinations of uranium mines and occurrences were performed in suspected favorable areas. Results of the work indicate good potential for shallow hydrothermal volcanogenic uranium deposits in the Lakeview favorable area, which comprises a northwest-trending belt of rhyolite intrusions in the eastern half of the quadrangle. The young age, peraluminous chemistry, and low thorium-to-uranium ratios of the rhyolite intrusions, as well as low uranium content of groundwater samples, indicate that uranium has not been leached from the intrusions by ground water. Therefore, supergene uranium deposits are not likely in the area. Scattered occurrences of ash-flow tuff in the east half of the quadrangle that contain high uranium and (or) thorium contents, and four occurrences of secondary uranium minerals in ash-flow tuff, indicate possible uranium deposits in ash flows in a poorly defined area that is partially coextensive with the Lakeview favorable area. Small granitic plutons with associated quartz-tourmaline breccia veins and base-metal occurrences may also be favorable for uranium deposits but were not examined during this study.

  3. Ammonia emissions from deciduous forest after leaf fall

    NASA Astrophysics Data System (ADS)

    Hansen, K.; Sørensen, L. L.; Hertel, O.; Geels, C.; Skjøth, C. A.; Jensen, B.; Boegh, E.

    2013-07-01

    The understanding of biochemical feedback mechanisms in the climate system is lacking knowledge in relation to bi-directional ammonia (NH3) exchange between natural ecosystems and the atmosphere. We therefore study the atmospheric NH3 fluxes during a 25-day period during autumn 2010 (21 October to 15 November) for the Danish beech forest Lille Bøgeskov to address the hypothesis that NH3 emissions occur from deciduous forests in relation to leaf fall. This is accomplished by using observations of vegetation status, NH3 fluxes and model calculations. Vegetation status was observed using plant area index (PAI) and leaf area index (LAI). NH3 fluxes were measured using the relaxed eddy accumulation (REA) method. The REA-based NH3 concentrations were compared to NH3 denuder measurements. Model calculations of the atmospheric NH3 concentration were obtained with the Danish Ammonia MOdelling System (DAMOS). The relative contribution from the forest components to the atmospheric NH3 flux was assessed using a simple two-layer bi-directional canopy compensation point model. A total of 57.7% of the fluxes measured showed emission and 19.5% showed deposition. A clear tendency of the flux going from deposition of -0.25 ± 0.30 μg NH3-N m-2 s-1 to emission of up to 0.67 ± 0.28 μg NH3-N m-2 s-1 throughout the measurement period was found. In the leaf fall period (23 October to 8 November), an increase in the atmospheric NH3 concentrations was related to the increasing forest NH3 flux. Following leaf fall, the magnitude and temporal structure of the measured NH3 emission fluxes could be adequately reproduced with the bi-directional resistance model; it suggested the forest ground layer (soil and litter) to be the main contributing component to the NH3 emissions. The modelled concentration from DAMOS fits well the measured concentrations before leaf fall, but during and after leaf fall, the modelled concentrations are too low. The results indicate that the missing contribution

  4. 14 CFR 399.39 - Equipment purchase deposits.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Equipment purchase deposits. 399.39 Section... Equipment purchase deposits. Equipment purchase deposits are advance payments made by air carriers to manufacturers for the purchase of equipment to be delivered in the future, or funds segregated by air...

  5. 14 CFR 399.39 - Equipment purchase deposits.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Equipment purchase deposits. 399.39 Section... Equipment purchase deposits. Equipment purchase deposits are advance payments made by air carriers to manufacturers for the purchase of equipment to be delivered in the future, or funds segregated by air...

  6. Measured Black Carbon Deposition on the Sierra Nevada Snow Pack and Implication for Snow Pack Retreat

    SciTech Connect

    Hadley, O.L.; Corrigan, C.E.; Kirchstetter, T.W.; Cliff, S.S.; Ramanathan, V.

    2010-01-12

    Modeling studies show that the darkening of snow and ice by black carbon deposition is a major factor for the rapid disappearance of arctic sea ice, mountain glaciers and snow packs. This study provides one of the first direct measurements for the efficient removal of black carbon from the atmosphere by snow and its subsequent deposition to the snow packs of California. The early melting of the snow packs in the Sierras is one of the contributing factors to the severe water problems in California. BC concentrations in falling snow were measured at two mountain locations and in rain at a coastal site. All three stations reveal large BC concentrations in precipitation, ranging from 1.7 ng/g to 12.9 ng/g. The BC concentrations in the air after the snow fall were negligible suggesting an extremely efficient removal of BC by snow. The data suggest that below cloud scavenging, rather than ice nuclei, was the dominant source of BC in the snow. A five-year comparison of BC, dust, and total fine aerosol mass concentrations at multiple sites reveals that the measurements made at the sampling sites were representative of large scale deposition in the Sierra Nevada. The relative concentration of iron and calcium in the mountain aerosol indicates that one-quarter to one-third of the BC may have been transported from Asia.

  7. The Fall 2000 and Fall 2001 SOHO-Ulysses Quadratures

    NASA Technical Reports Server (NTRS)

    Suess, S. T.; Poletto, G.

    2000-01-01

    SOHO-Ulysses quadrature occurs when the SOHO-Sun-Ulysses included angle is 90 degrees. It is only at such times that the same plasma leaving the Sun in the direction of Ulysses can first be remotely analyzed with SOHO instruments and then later be sampled in situ by Ulysses instruments. The quadratures in December 2000 and 2001 are of special significance because Ulysses will be near the south and north heliographic poles, respectively, and the solar cycle will be near sunspot maximum. Quadrature geometry is sometimes confusing and observations are influenced by solar rotation. The Fall 2000 and 2001 quadratures are more complex than usual because Ulysses is not in a true polar orbit and the orbital speed of Ulysses about the Sun is becoming comparable to the speed of SOHO about the Sun. In 2000 Ulysses will always be slightly behind the pole but will appear to hang over the pole for over two months because it is moving around the Sun in the same direction as SOHO. In 20001, Ulysses will be slightly in front of the pole so that its footpoint will be directly observable. Detailed plots will be shown of the relative positions of SOHO and Ulysses will their relative positions. In neither case is true quadrature actually achieved, but this works to the observers advantage in 2001.

  8. The Fall 2000 and Fall 2001 SOHO-Ulysses Quadratures

    NASA Technical Reports Server (NTRS)

    Suess, S. T.; Poletto, G.; Rose, M. Franklin (Technical Monitor)

    2001-01-01

    SOHO-Ulysses quadrature occurs when the SOHO-Sun-Ulysses included angle is 90 degrees. It is only at such times that the same plasma leaving the Sun in the direction of Ulysses can first be remotely analyzed with SOHO instruments and then later be sampled in situ by Ulysses instruments. The quadratures in December 2000 and 2001 are of special significance because Ulysses will be near the south and north heliographic poles, respectively, and the solar cycle will be near sunspot maximum. Quadrature geometry is sometimes confusing and observations are influenced by solar rotation. The Fall 2000 and 2001 quadratures are more complex than usual because Ulysses is not in a true polar orbit and the orbital speed of Ulysses about the Sun is becoming comparable to the speed of SOHO about the Sun. In 2000 Ulysses will always be slightly behind the pole but will appear to hang over the pole for over two months because it is moving around the Sun in the same direction as SOHO. In 2001 Ulysses will be slightly in front of the pole so that its footpoint will be directly observable. Detailed plots will be shown of the relative positions of SOHO and Ulysses will their relative positions. In neither case is true quadrature actually achieved, but this works to the observers advantage in 2001.

  9. Applications Using AIRS Data

    NASA Astrophysics Data System (ADS)

    Ray, S. E.; Pagano, T. S.; Fetzer, E. J.; Lambrigtsen, B.; Olsen, E. T.; Teixeira, J.; Licata, S. J.; Hall, J. R.; Thompson, C. K.

    2015-12-01

    The Atmospheric Infrared Sounder (AIRS) on NASA's Aqua spacecraft has been returning daily global observations of Earth's atmospheric constituents and properties since 2002. With a 12-year data record and daily, global observations in near real-time, AIRS data can play a role in applications that fall under many of the NASA Applied Sciences focus areas. For vector-borne disease, research is underway using AIRS near surface retrievals to assess outbreak risk, mosquito incubation periods and epidemic potential for dengue fever, malaria, and West Nile virus. For drought applications, AIRS temperature and humidity data are being used in the development of new drought indicators and improvement in the understanding of drought development. For volcanic hazards, new algorithms using AIRS data are in development to improve the reporting of sulfur dioxide concentration, the burden and height of volcanic ash and dust, all of which pose a safety threat to aircraft. In addition, anomaly maps of many of AIRS standard products are being produced to help highlight "hot spots" and illustrate trends. To distribute it's applications imagery, AIRS is leveraging existing NASA data frameworks and organizations to facilitate archiving, distribution and participation in the BEDI. This poster will communicate the status of the applications effort for the AIRS Project and provide examples of new maps designed to best communicate the AIRS data.

  10. The stimuli evoking the aerial-righting posture of falling pea aphids.

    PubMed

    Meresman, Yonatan; Ribak, Gal; Weihs, Daniel; Inbar, Moshe

    2014-10-01

    Some wingless insects possess aerial righting reflexes, suggesting that adaptation for controlling body orientation while falling through air could have preceded flight. When threatened by natural enemies, wingless pea aphids (Acyrthosiphon pisum) may drop off their host plant and assume a stereotypic posture that rotates them in midair to land on their feet. The sensory information triggering aphids to assume this posture has so far been unknown. We subjected aphids to a series of tests, isolating the sensory cues experienced during free-fall. Falling aphids assumed the righting posture and landed upright irrespective of whether the experiments were carried out in the light or in complete darkness. Detachment of the tarsi from the substrate triggered the aphids to assume the posture rapidly, but only for a brief period. Rotation (mainly roll and yaw) of the body in air, in the light, caused aphids to assume the posture and remain in it throughout rotation. In contrast, aphids rotated in the dark did not respond. Acceleration associated with falling or airflow over the body per se did not trigger the posture. However, sensing motion relative to air heightened the aphids' responsiveness to rotation in the light. These results suggest that the righting posture of aphids is triggered by a tarsal reflex, but, once the aphid is airborne, vision and a sense of motion relative to air can augment the response. Hence, aerial righting in a wingless insect could have emerged as a basic tarsal response and developed further to include secondary sensory cues typical of falling.

  11. IDENTIFYING ROOF FALL PREDICTORS USING FUZZY CLASSIFICATION

    SciTech Connect

    Bertoncini, C. A.; Hinders, M. K.

    2010-02-22

    Microseismic monitoring involves placing geophones on the rock surfaces of a mine to record seismic activity. Classification of microseismic mine data can be used to predict seismic events in a mine to mitigate mining hazards, such as roof falls, where properly bolting and bracing the roof is often an insufficient method of preventing weak roofs from destabilizing. In this study, six months of recorded acoustic waveforms from microseismic monitoring in a Pennsylvania limestone mine were analyzed using classification techniques to predict roof falls. Fuzzy classification using features selected for computational ease was applied on the mine data. Both large roof fall events could be predicted using a Roof Fall Index (RFI) metric calculated from the results of the fuzzy classification. RFI was successfully used to resolve the two significant roof fall events and predicted both events by at least 15 hours before visual signs of the roof falls were evident.

  12. Source location of falling tone chorus

    NASA Astrophysics Data System (ADS)

    Kurita, Satoshi; Misawa, Hiroaki; Cully, Christopher M.; Le Contel, Olivier; Angelopoulos, Vassilis

    2012-11-01

    Chorus is characterized by its fine structures consisting of rising or falling tones believed to result from nonlinear wave-particle interactions. However, previous studies have showed that the intensity and propagation characteristics of rising and falling tone chorus are quite different, suggesting that their generation processes might be different. In this paper, the propagation direction of falling tone chorus is statistically investigated to identify its source region based on the Poynting vector measurement with THEMIS. The result shows that the falling tone chorus propagates from the magnetic equator to higher latitude both in the northern and southern hemispheres, in the same way as rising tone chorus. Our result shows that the magnetic equator is the common source location for both rising and falling tone chorus. The result emphasizes that the different properties between rising and falling tone chorus originate from their generation mechanism rather than source region.

  13. Prevention of construction falls by organizational intervention

    PubMed Central

    Becker, P; Fullen, M; Akladios, M; Hobbs, G

    2001-01-01

    Objectives—Determine if a university based (third party) intervention can improve construction contractor organizational performance to increase use of fall prevention practices and technologies. Setting—Falls are the leading cause of worker injury and death in the construction industry. Equipment and practices that can prevent falls are often not used appropriately in the dynamic construction work environment. Methods—A contractual partnership between a university and construction contractors created management systems to ensure use of fall protection measures. Audits by university faculty provided accountability for implementing the fall prevention system. Evaluation was conducted by quasiexperimental methodology comparing changes in audit score from baseline to fifth quarter from baseline for intervention and control contractors. Results—Audit scores improvement was greater for intervention than for control contractor group. Conclusion—A third party intervention can improve contractor fall prevention performance. PMID:11565975

  14. Economic assessment of materials damage in the South Coast Air Basin: A case study of acid-deposition effects on painted wood surfaces using individual maintenance-behavior data

    SciTech Connect

    Horst, R.L.; Zankel, K.; Kamen, S.; Rosso, D.

    1990-05-01

    The case study examines the economic impact of acid deposition damage to painted wood surfaces in the South Coast Air Basin of Southern California. The output of the analysis is an estimate of the annual cost-savings that would be realized for a uniform 10 percent reduction in NO2 concentrations. The economic estimates are developed for individuals who reside in single family homes, make their own maintenance decisions, and perform one of six specific maintenance tasks. Individual maintenance behavior data are collected as part of the study and permit a more disaggregate analysis than earlier economic materials damage assessments. The economic estimates are derived in two ways. First, physical damage functions are used to predict rates of damage. The analysis indicates that the best estimates of annual cost-savings for the scenario examined are $0.7 million (1988) for the physical damage function approach and $3.6 million (1988) for the economic damage function approach. Consideration of some of the factors that contribute to uncertainty indicate that the cost-savings estimates could vary by at least a factor of two.

  15. 3D simulation for falling papers

    NASA Astrophysics Data System (ADS)

    Aoki, Takayuki

    2001-12-01

    The combination of IDO (Interpolated Differential Operator) scheme, Cut Cell technique, and overlapping grid method make it possible to simulate the falling process of papers. We have the result of the falling with fluttering trajectory for a certain initial angle of the paper, and the fluttering mechanism becomes clear. It is shown that the simulation is applicable to the phenomena of falling leaves with complex shape.

  16. 1. Photocopy of a photographca. 1920 VIEW OF AMERICAN FALLS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Photocopy of a photograph--ca. 1920 VIEW OF AMERICAN FALLS PRIOR TO CONSTRUCTION OF HYDROELECTRIC PLANTS - American Falls Water, Power & Light Company, Island Power Plant, Snake River, below American Falls Dam, American Falls, Power County, ID

  17. Effectiveness of team training on fall prevention.

    PubMed

    Spiva, LeeAnna; Robertson, Bethany; Delk, Marcia L; Patrick, Sara; Kimrey, Margaret Michelle; Green, Beverly; Gallagher, Erin

    2014-01-01

    A longitudinal, repeated-measures design with intervention and comparison groups was used to evaluate the effect of a training curriculum based on TeamSTEPPS with video vignettes focusing on fall prevention. Questionnaires, behavioral observations, and fall data were collected over 9 months from both groups located at separate hospitals. The intervention group questionnaire scores improved on all measures except teamwork perception, while observations revealed an improvement in communication compared with the control group. Furthermore, a 60% fall reduction rate was reported in the intervention group. Team training may be a promising intervention to reduce falls.

  18. Radar fall detection using principal component analysis

    NASA Astrophysics Data System (ADS)

    Jokanovic, Branka; Amin, Moeness; Ahmad, Fauzia; Boashash, Boualem

    2016-05-01

    Falls are a major cause of fatal and nonfatal injuries in people aged 65 years and older. Radar has the potential to become one of the leading technologies for fall detection, thereby enabling the elderly to live independently. Existing techniques for fall detection using radar are based on manual feature extraction and require significant parameter tuning in order to provide successful detections. In this paper, we employ principal component analysis for fall detection, wherein eigen images of observed motions are employed for classification. Using real data, we demonstrate that the PCA based technique provides performance improvement over the conventional feature extraction methods.

  19. Klamath Falls geothermal field, Oregon

    SciTech Connect

    Lienau, P.J.; Culver, G.; Lund, J.W.

    1989-09-01

    Klamath Falls, Oregon, is located in a Known Geothermal Resource Area which has been used by residents, principally to obtain geothermal fluids for space heating, at least since the turn of the century. Over 500 shallow-depth wells ranging from 90 to 2,000 ft (27 to 610 m) in depth are used to heat (35 MWt) over 600 structures. This utilization includes the heating of homes, apartments, schools, commercial buildings, hospital, county jail, YMCA, and swimming pools by individual wells and three district heating systems. Geothermal well temperatures range from 100 to 230{degree}F (38 to 110{degree}C) and the most common practice is to use downhole heat exchangers with city water as the circulating fluid. Larger facilities and district heating systems use lineshaft vertical turbine pumps and plate heat exchangers. Well water chemistry indicates approximately 800 ppM dissolved solids, with sodium sulfate having the highest concentration. Some scaling and corrosion does occur on the downhole heat exchangers (black iron pipe) and on heating systems where the geo-fluid is used directly. 73 refs., 49 figs., 6 tabs.

  20. Air Entraining Flows

    NASA Astrophysics Data System (ADS)

    Prosperetti, Andrea

    2001-11-01

    Air entraining flows are frequently encountered in Nature (e.g. breaking waves, waterfalls, rain over water bodies) and in technological applications (gas-liquid chemical reactors, water treatment, aquaculture, and others). Superficially, one may distinguish between transient events, such as a breaking wave, and steady situations, e.g. a falling jet. However, when viscosity is not important, the process of air entrainment turns out to be the consequence of local transient events even in steady flows. For example, surface disturbances convected by a nominally steady jet impact the receiving liquid, create a deep depression, which collapses entraining an air pocket. (In practice this basic mechanism is complicated by the presence of waves, vortical flows, and other factors.) This talk will describe several examples of air-entraining flows illustrating the fluid mechanic principles involved with high-speed movies and numerical computations.

  1. Rotation in Free Fall of Rectangular Wings of Elongated Shape

    NASA Technical Reports Server (NTRS)

    Dupleich, Paul

    1949-01-01

    The present report of Mr. Dupleich is the summary of a very extensive experimental study of the well-known mechanical phenomenon: the rotation in free fall (* air, for instance) of more or less elongated rectangles cut out of paper or pasteboard. This phenomenon, the conditions for existence of which depend chiefly on the elongated of the small plate and its weight per unit area, is essentially an aerodynamic phenomenon and as such, raises questions of a certain interest to our department.We believe that the modern concepts of the mechanics of fluids do not have the range attributed to them.

  2. History of falls, gait, balance, and fall risks in older cancer survivors living in the community

    PubMed Central

    Huang, Min H; Shilling, Tracy; Miller, Kara A; Smith, Kristin; LaVictoire, Kayle

    2015-01-01

    Older cancer survivors may be predisposed to falls because cancer-related sequelae affect virtually all body systems. The use of a history of falls, gait speed, and balance tests to assess fall risks remains to be investigated in this population. This study examined the relationship of previous falls, gait, and balance with falls in community-dwelling older cancer survivors. At the baseline, demographics, health information, and the history of falls in the past year were obtained through interviewing. Participants performed tests including gait speed, Balance Evaluation Systems Test, and short-version of Activities-specific Balance Confidence scale. Falls were tracked by mailing of monthly reports for 6 months. A “faller” was a person with ≥1 fall during follow-up. Univariate analyses, including independent sample t-tests and Fisher’s exact tests, compared baseline demographics, gait speed, and balance between fallers and non-fallers. For univariate analyses, Bonferroni correction was applied for multiple comparisons. Baseline variables with P<0.15 were included in a forward logistic regression model to identify factors predictive of falls with age as covariate. Sensitivity and specificity of each predictor of falls in the model were calculated. Significance level for the regression analysis was P<0.05. During follow-up, 59% of participants had one or more falls. Baseline demographics, health information, history of falls, gaits speed, and balance tests did not differ significantly between fallers and non-fallers. Forward logistic regression revealed that a history of falls was a significant predictor of falls in the final model (odds ratio =6.81; 95% confidence interval =1.594–29.074) (P<0.05). Sensitivity and specificity for correctly identifying a faller using the positive history of falls were 74% and 69%, respectively. Current findings suggested that for community-dwelling older cancer survivors with mixed diagnoses, asking about the history of falls

  3. History of falls, gait, balance, and fall risks in older cancer survivors living in the community.

    PubMed

    Huang, Min H; Shilling, Tracy; Miller, Kara A; Smith, Kristin; LaVictoire, Kayle

    2015-01-01

    Older cancer survivors may be predisposed to falls because cancer-related sequelae affect virtually all body systems. The use of a history of falls, gait speed, and balance tests to assess fall risks remains to be investigated in this population. This study examined the relationship of previous falls, gait, and balance with falls in community-dwelling older cancer survivors. At the baseline, demographics, health information, and the history of falls in the past year were obtained through interviewing. Participants performed tests including gait speed, Balance Evaluation Systems Test, and short-version of Activities-specific Balance Confidence scale. Falls were tracked by mailing of monthly reports for 6 months. A "faller" was a person with ≥1 fall during follow-up. Univariate analyses, including independent sample t-tests and Fisher's exact tests, compared baseline demographics, gait speed, and balance between fallers and non-fallers. For univariate analyses, Bonferroni correction was applied for multiple comparisons. Baseline variables with P<0.15 were included in a forward logistic regression model to identify factors predictive of falls with age as covariate. Sensitivity and specificity of each predictor of falls in the model were calculated. Significance level for the regression analysis was P<0.05. During follow-up, 59% of participants had one or more falls. Baseline demographics, health information, history of falls, gaits speed, and balance tests did not differ significantly between fallers and non-fallers. Forward logistic regression revealed that a history of falls was a significant predictor of falls in the final model (odds ratio =6.81; 95% confidence interval =1.594-29.074) (P<0.05). Sensitivity and specificity for correctly identifying a faller using the positive history of falls were 74% and 69%, respectively. Current findings suggested that for community-dwelling older cancer survivors with mixed diagnoses, asking about the history of falls may

  4. Prevalence and cost of imaging in inpatient falls: the rising cost of falling

    PubMed Central

    Fields, Jessica; Alturkistani, Tahani; Kumar, Neal; Kanuri, Arjun; Salem, Deeb N; Munn, Samson; Blazey-Martin, Deborah

    2015-01-01

    Objective To quantify the type, prevalence, and cost of imaging following inpatient falls, identify factors associated with post-fall imaging, and determine correlates of positive versus negative imaging. Design Single-center retrospective cohort study of inpatient falls. Data were collected from the hospital’s adverse event reporting system, DrQuality. Age, sex, date, time, and location of fall, clinical service, Morse Fall Scale/fall protocol, admitting diagnosis, and fall-related imaging studies were reviewed. Cost included professional and facilities fees for each study. Setting Four hundred and fifteen bed urban academic hospital over 3 years (2008–2010). Patients All adult inpatient falls during the study period were included. Falls experienced by patients aged <18 years, outpatient and emergency patients, visitors to the hospital, and staff were excluded. Measurements and main results Five hundred and thirty inpatient falls occurred during the study period, average patient age 60.7 years (range 20–98). More than half of falls were men (55%) and patients considered at risk of falls (56%). Falls were evenly distributed across morning (33%), evening (34%), and night (33%) shifts. Of 530 falls, 178 (34%) patients were imaged with 262 studies. Twenty percent of patients imaged had at least one positive imaging study attributed to the fall and 82% of studies were negative. Total cost of imaging was $160,897, 63% ($100,700) from head computed tomography (CT). Conclusion Inpatient falls affect patients of both sexes, all ages, occur at any time of day and lead to expensive imaging, mainly from head CTs. Further study should be targeted toward clarifying the indications for head CT after inpatient falls and validating risk models for positive and negative imaging, in order to decrease unnecessary imaging and thereby limit unnecessary cost and radiation exposure. PMID:26082653

  5. 180. Photocopy of Photograph, Twin Falls Canal Company. E. Pettygro, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    180. Photocopy of Photograph, Twin Falls Canal Company. E. Pettygro, Photographer, date unknown. BLASTING TWIN FALLS CANAL, TWIN FALLS COUNTY; BLASTING COTTONWOOD AREA TO REPLACE FLUME BY RUNNING HIGH LINE THROUGH SOLID ROCK. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

  6. Biochemical activity of centipedegrass against fall armyworm larvae.

    PubMed

    Wiseman, B R; Gueldner, R C; Lynch, R E; Severson, R F

    1990-09-01

    Centipedegrass,Eremochloa ophiuroides (Munro) Hack, severely inhibits growth of the fall armyworm larva,Spodoptera frugiperda (J.E. Smith). Fresh centipedegrass extracts and extract fractions were deposited on Celufil, incorporated into meridic-based diets and bioassayed against neonate larvae of the fall armyworm in the laboratory. The methanol extract (F1) caused the greatest reduction in larval weight. When F1, was partitioned between méthylene chloride and water, the activity was transferred to the water-soluble fraction (F5), which, when further fractionated using preparative C-18 reverse-phase chromatography, yielded active F7 and F8 fractions. Gas chromatograph-mass spectrometry and high-pressure liquid chromatography (HPLC) showed F7 to be 95% caffeoylquinic acids with chlorogenic acid as the major constituent. HPLC analysis of F8 revealed maysin [2″-O- α-L-rhamnosyl-6-C-(6-deoxy-Xylo-hexos-4-ulosyl)luteolin] and other luteolin derivatives. Chlorogenic acid and other caffeoylquinic acids, maysin, and other luteolin derivatives are the major factors responsible for the antibiotic resistance of centipedegrass to larvae of the fall armyworm.

  7. Fall Meeting by the numbers

    NASA Astrophysics Data System (ADS)

    Asher, Pranoti

    2012-02-01

    - Visits to the Fall Meeting Web site: 650,000 - Total participants at the meeting: 20,890 - Abstracts submitted to the meeting: 20,087 - Donors who attended and took advantage of donor lounges: 1835 - Total attendance at Simon Winchester's Presidential Forum Lecture: 1200 - Total attendance at the Honors Banquet: 905 - Books sold at the AGU Marketplace: 671 - Individuals registered for the Fun Run: 487 - Students who participated in the Student Breakfast: 450 - Individuals who crossed the finish line at the Fun Run: 384 - Total attendees at Exploration Station: 307 - Total booths sold in the Exhibit Hall: 304 - registered for the meeting: 288 - Membership transactions completed for renewing and registering members at AGU Marketplace: 156 - Meeting attendees who were past Congressional Visits Day participants: 82 - Editors, associate editors, and their student guests who visited the Editors Resource Center: 63 - Copies of Navigating Graduate School and Beyond: A Career Guide for Graduate Students and a Must Read for Every Advisor sold during and after the talk and book signing by author Sundar A. Christopher: 50 - Kegs of beer consumed during the Ice Breaker on Sunday, 4 December: 48 - Hours of video footage shot at the meeting by the AGU videographer: 40 - Potential geopress authors and editors who attended the daily "Come Publish With geopress" sessions in the AGU Marketplace: 31 - Press conferences held at the meeting: 25 - Average age of minors attending Exploration Station: 8.7 - Educational seminars sponsored by AGU Publications: 2 (one on how to write a good scientific paper and the other on the rewards of reviewing) - Watching three preschoolers in space suits waiting to meet astronaut Andrew Feustel after the Public Lecture: Priceless (with apologies to Mastercard®)

  8. How fast does a building fall?

    NASA Astrophysics Data System (ADS)

    Denny, Mark

    2010-07-01

    In this paper, the time required for a tower block to collapse is calculated. The tower collapses progressively, with one floor falling onto the floor below, causing it to fall. The rate of collapse is found to be not much slower than freefall. The calculation is an engaging and relevant application of Newton's laws, suitable for undergraduate teaching.

  9. 29 CFR 1917.41 - House falls.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 7 2013-07-01 2013-07-01 false House falls. 1917.41 Section 1917.41 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) MARINE TERMINALS Cargo Handling Gear and Equipment § 1917.41 House falls. (a) Span beams shall be...

  10. Washington Community Colleges Fall Quarter Report, 1982.

    ERIC Educational Resources Information Center

    Story, Sherie; And Others

    Information on enrollments and student characteristics at Washington state community colleges is provided in this report for fall 1982. After introductory material and report highlights, tables provide data on headcount and full-time equivalent (FTE) enrollment for fall quarters 1978 through 1982; FTE and headcount by course intent category;…

  11. The Latino Experience in Central Falls

    ERIC Educational Resources Information Center

    Holland, William R.

    2011-01-01

    Central Falls is, by far, the poorest community in Rhode Island. More than 40 percent of the children under 18 live in poverty, and 40 percent of that group live in severe poverty. At Central Falls High School, low-income Latino students have fallen behind their white counterparts, with shockingly low graduation, poor literacy, and low…

  12. Analysis of Fall 1994 Course Grades.

    ERIC Educational Resources Information Center

    Pima Community Coll., Tucson, AZ. Office of Research and Planning.

    This report provides data on withdrawal and success rates and grades earned in fall 1994 at the five campuses of Pima Community College (PCC), in Arizona. Following a literature review on national course grades, descriptions are provided of the following: (1) grades and withdrawals for fall 1979, 1984, 1989, and 1994, indicating that the number of…

  13. 29 CFR 1917.41 - House falls.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false House falls. 1917.41 Section 1917.41 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) MARINE TERMINALS Cargo Handling Gear and Equipment § 1917.41 House falls. (a) Span beams shall be...

  14. Central Falls' Kids First: A Case Study.

    ERIC Educational Resources Information Center

    Tufts Univ., Medford, MA. Center on Hunger, Poverty and Nutrition Policy.

    Central Falls' Kids First, a 3-year initiative was designed to eradicate local childhood hunger through the expansion of federal child nutrition programs in Central Falls, a small, densely populated, ethnically diverse and low-income city in northeastern Rhode Island. A strong community partnership was created and included the office of the city's…

  15. [Improving fall prevention in the elderly].

    PubMed

    Bongue, Bienvenu; Hugues, Julie; Achour, Émilie; Colvez, Alain; Sass, Catherine

    2016-01-01

    The prevention of falls in the elderly requires action on several levels. Firstly, it is essential to identify those at risk of a fall. They must then be encouraged to do appropriate physical and sports activities, a factor of prevention. Social workers have a major role to play in supporting elderly people and encouraging them to participate in such programmes. PMID:27449306

  16. How Fast Does a Building Fall?

    ERIC Educational Resources Information Center

    Denny, Mark

    2010-01-01

    In this paper, the time required for a tower block to collapse is calculated. The tower collapses progressively, with one floor falling onto the floor below, causing it to fall. The rate of collapse is found to be not much slower than freefall. The calculation is an engaging and relevant application of Newton's laws, suitable for undergraduate…

  17. Osteosarcopenic obesity and fall prevention strategies.

    PubMed

    Hita-Contreras, Fidel; Martínez-Amat, Antonio; Cruz-Díaz, David; Pérez-López, Faustino R

    2015-02-01

    Sarcopenia, obesity, and osteoporosis are three interrelated entities which may share common pathophysiological factors. In the last decades, overall survival has drastically increased. Postmenopausal women, due to their estrogen depletion, are at higher risk of developing any of these three conditions or the three, which is termed osteosarcopenic obesity. One of the most common health problems among these patients is the elevated risk of falls and fractures. Falls and fall-related injuries are one of the major causes of mortality and morbidity in older adults, and have a significant impact on social, economical and health-related costs. Several extrinsic and intrinsic risk factors have been described that play a role in the etiology of falls. A therapeutic approach to osteosarcopenic obesity aimed at the prevention of falls must include several factors, and act on those risk elements which can be effectively modified. An adequate weight-loss diet and a good nutritional intake, with an appropriate amount of vitamin D and the right protein/carbohydrates ratio, may contribute to the prevention of falls. The recommendation of physical exercise, both traditional (resistance or aerobic training) and more recent varieties (Tai Chi, Pilates, body vibration), can improve balance and positively contribute to fall prevention, whether by itself or in combination with other therapeutic strategies. Finally, a pharmacological approach, especially one focused on hormone therapy, has shown to have a positive effect on postmenopausal women's balance, leading to a decreased risk of falls. PMID:25533145

  18. Falls - Multiple Languages: MedlinePlus

    MedlinePlus

    ... السقوط في المستشفى - العربية Bilingual PDF Health Information Translations Safety Tips to Prevent Falls at Home (Arabic) العربية Bilingual PDF Health Information Translations Bosnian (Bosanski) Preventing Falls in the Hospital Sprječavanje ...

  19. Why Does My Foot Fall Asleep?

    MedlinePlus

    ... Help White House Lunch Recipes Why Does My Foot Fall Asleep? KidsHealth > For Kids > Why Does My Foot Fall Asleep? Print A A A Text Size ... while you might have lost feeling in your foot, it might have felt heavy, or you might ...

  20. Fall Detection Using Smartphone Audio Features.

    PubMed

    Cheffena, Michael

    2016-07-01

    An automated fall detection system based on smartphone audio features is developed. The spectrogram, mel frequency cepstral coefficents (MFCCs), linear predictive coding (LPC), and matching pursuit (MP) features of different fall and no-fall sound events are extracted from experimental data. Based on the extracted audio features, four different machine learning classifiers: k-nearest neighbor classifier (k-NN), support vector machine (SVM), least squares method (LSM), and artificial neural network (ANN) are investigated for distinguishing between fall and no-fall events. For each audio feature, the performance of each classifier in terms of sensitivity, specificity, accuracy, and computational complexity is evaluated. The best performance is achieved using spectrogram features with ANN classifier with sensitivity, specificity, and accuracy all above 98%. The classifier also has acceptable computational requirement for training and testing. The system is applicable in home environments where the phone is placed in the vicinity of the user.

  1. Measurements of iodine uptake in falling water droplets

    SciTech Connect

    Hyder, M.L.

    1989-12-31

    The removal of gaseous iodine from air by water sprays was measured, using both ordinary water and a solution buffered to a pH near 9.5 with a carbonate mixture. The results were compared to the theoretical predictions of the I2WASH computer code. In all experiments, using both large and small spray droplets, the solution at the higher pH was approximately three times as effective at absorbing iodine from the air. This agrees with the predictions of the computer model for the smaller droplets studied. The computer code predicts no pH effect for large drops, probably because it assumes a well-mixed drop, and mixing during the fall time is too slow.

  2. MODIS volcanic ash retrievals vs FALL3D transport model: a quantitative comparison

    NASA Astrophysics Data System (ADS)

    Corradini, S.; Merucci, L.; Folch, A.

    2010-12-01

    Satellite retrievals and transport models represents the key tools to monitor the volcanic clouds evolution. Because of the harming effects of fine ash particles on aircrafts, the real-time tracking and forecasting of volcanic clouds is key for aviation safety. Together with the security reasons also the economical consequences of a disruption of airports must be taken into account. The airport closures due to the recent Icelandic Eyjafjöll eruption caused millions of passengers to be stranded not only in Europe, but across the world. IATA (the International Air Transport Association) estimates that the worldwide airline industry has lost a total of about 2.5 billion of Euro during the disruption. Both security and economical issues require reliable and robust ash cloud retrievals and trajectory forecasting. The intercomparison between remote sensing and modeling is required to assure precise and reliable volcanic ash products. In this work we perform a quantitative comparison between Moderate Resolution Imaging Spectroradiometer (MODIS) retrievals of volcanic ash cloud mass and Aerosol Optical Depth (AOD) with the FALL3D ash dispersal model. MODIS, aboard the NASA-Terra and NASA-Aqua polar satellites, is a multispectral instrument with 36 spectral bands operating in the VIS-TIR spectral range and spatial resolution varying between 250 and 1000 m at nadir. The MODIS channels centered around 11 and 12 micron have been used for the ash retrievals through the Brightness Temperature Difference algorithm and MODTRAN simulations. FALL3D is a 3-D time-dependent Eulerian model for the transport and deposition of volcanic particles that outputs, among other variables, cloud column mass and AOD. Three MODIS images collected the October 28, 29 and 30 on Mt. Etna volcano during the 2002 eruption have been considered as test cases. The results show a general good agreement between the retrieved and the modeled volcanic clouds in the first 300 km from the vents. Even if the

  3. Air Pollution

    MedlinePlus

    Air pollution is a mixture of solid particles and gases in the air. Car emissions, chemicals from factories, ... Ozone, a gas, is a major part of air pollution in cities. When ozone forms air pollution, it's ...

  4. Selective attentional processing to fall-relevant stimuli among older adults who fear falling.

    PubMed

    Brown, Lesley A; White, Patti; Doan, Jonathan B; de Bruin, Natalie

    2011-05-01

    Fear of falling is known to affect more than half of community-dwelling older adults over 60 years of age. This fear is associated with physical and psychological effects that increase the risk of falling. The authors' theory is that attentional processing biases may exist in this population that serve to perpetuate fear of falling and subsequently increase fall risk. As a starting point in testing this proposition, the authors examined selective attentional processing bias to fall-relevant stimuli among older adults. Thirty older adult participants (M(age) = 70.8 ± 5.8), self-categorized to be Fearful of Falling (FF, n = 15) or Non-Fearful of Falling (NF, n = 15) completed a visual dot-probe paradigm to determine detection latencies to fall-threatening and general-threat stimuli. Attentional processing was defined using three index scores: attentional bias, congruency index, and incongruency index. Bias indicates capture of attention, whereas congruency and incongruency imply vigilance and disengagement difficulty, respectively. Both groups showed an attentional bias to fall-threat words but those who were fearful of falling also showed an incongruency effect for fall-threat words. These findings confirm that selective attentional processing profiles for fall-relevant stimuli differ between older adults who exhibit fear of falling and those who do not have this fear. Moreover, in accordance with current interpretations of selective attentional processing, the incongruency effect noted among fall-fearful older adults presents a possibility for a difficulty disengaging from fall-threatening stimuli.

  5. Depositional history of Louisiana-Mississippi outer continental shelf

    USGS Publications Warehouse

    Kindinger, J.L.; Miller, R.J.; Stelting, C.E.

    1982-01-01

    A geological study was undertaken in 1981 in the Louisiana-Mississippi outer continental shelf for the Bureau of Land Management. The study included a high-resolution seismic reflection survey, surficial sediment sampling and surface current drifter sampling. Approximately 7100 sq km of the Louisiana-Mississippi shelf and upper slope were surveyed. The sea floor of the entire area is relatively smooth except for occasional areas of uplift produced by diapiric intrusion along the upper slope. Characteristics of the topography and subsurface shelf sediments are the result of depositional sequences due to delta outbuilding over transgressive sediments with intervening periods of erosion during low sea level stands. Little evidence of structural deformation such as faults, diapirs, and shallow gas is present on the shelf and only a few minor faults and scarps are found on the slope. Minisparker seismic records in combination with air gun (40 and 5 cu in) and 3.5-kHz subbottom profile records reveal that seven major stages of shelf development have occurred since the middle Pleistocene. The shelf development has been controlled by the rise and fall of sea level. These stages are defined by four major unconformities, several depositions of transgressive sediments, sequences of river channeling and progradational delta deposits. Surficial sediment sample and seismic records indicate tat the last major depositional event was the progradation of the St. Bernard Delta lobe. This delta lobe covered the northwestern and central regions. Surficial sediments in most of the study area are the product of the reworking of the San Bernard Delta lobe and previous progradations.

  6. [Monitoring nitrogen deposition on temperate grassland in Inner Mongolia].

    PubMed

    Zhang, Ju; Kang, Rong-hua; Zhao, Bin; Huang, Yong-mei; Ye, Zhi-xiang; Duan, Lei

    2013-09-01

    Nitrogen deposition on temperate steppe was monitored from November 2011 to October 2012 in Taipusi County, Inner Mongolia. The dry deposition of gaseous nitrogen compounds was calculated based on online-monitored atmospheric concentrations of NH3 and NO2 and dry deposition velocity simulated by CMAQ model. The wet deposition, dry deposition of particle, and throughfall deposition were also estimated by collecting rainfall, dust fall, and throughfall samples and the chemical analysis of NH4+ and NO3-concentrations. Results showed that the total deposition of nitrogen was up to 3.43 g x (m2 x a)(-1), which might be harmful to the ecosystem. The wet deposition accounted for about 44% of the total deposition, while dry deposition of gases and particle accounted for 38% and 18%, respectively. Since the deposition contributed more than wet deposition, a great attention should be paid on dry deposition monitoring. However, the very simple method for total deposition monitoring based on throughfall seemed not suitable for grassland because the monitored throughfall deposition was much lower than the total deposition. In addition, reduced nitrogen (NH4+ and NH3) contributed to 71% of the total deposition, while oxidation nitrogen (NO3- and NO2) was only 29%. Therefore, NH3 emission reduction should be considered as important as nitrogen oxides (NO3x) for controlling nitrogen deposition.

  7. A Matter of Energy Efficiency: From Modeling Falling Raindrops to Controlling Rocket Thrust

    NASA Astrophysics Data System (ADS)

    Harding, Eric

    2014-03-01

    A power-law accretion model is used to investigate the energy dynamics of a falling raindrop in a Newtonian gravitational field where air resistance is included in the analysis. This model is seen to be related to the rate of ejection of exhaust gases for the rocket problem. Energy analysis of the falling raindrop will be presented for the motion of very small droplets, those of diameter less than 0.003 inches, which are falling at relatively slow speeds, of less than 0.188 m/s. The deviation from self-similar accretion, and other relevant model parameters will be re-interpreted as related to control parameters in the rocket problem. Efficiency of natural energy transfer for the falling raindrop will be compared with the power transfer model for the rocket. Acknowledge support from Dept. of Physics, Engineering and Geoscience, Noyce TPOD-STEM Grant, GT STEP Grant.

  8. Particle deposition in ventilation ducts

    SciTech Connect

    Sippola, Mark R.

    2002-09-01

    Exposure to airborne particles is detrimental to human health and indoor exposures dominate total exposures for most people. The accidental or intentional release of aerosolized chemical and biological agents within or near a building can lead to exposures of building occupants to hazardous agents and costly building remediation. Particle deposition in heating, ventilation and air-conditioning (HVAC) systems may significantly influence exposures to particles indoors, diminish HVAC performance and lead to secondary pollutant release within buildings. This dissertation advances the understanding of particle behavior in HVAC systems and the fates of indoor particles by means of experiments and modeling. Laboratory experiments were conducted to quantify particle deposition rates in horizontal ventilation ducts using real HVAC materials. Particle deposition experiments were conducted in steel and internally insulated ducts at air speeds typically found in ventilation ducts, 2-9 m/s. Behaviors of monodisperse particles with diameters in the size range 1-16 {micro}m were investigated. Deposition rates were measured in straight ducts with a fully developed turbulent flow profile, straight ducts with a developing turbulent flow profile, in duct bends and at S-connector pieces located at duct junctions. In straight ducts with fully developed turbulence, experiments showed deposition rates to be highest at duct floors, intermediate at duct walls, and lowest at duct ceilings. Deposition rates to a given surface increased with an increase in particle size or air speed. Deposition was much higher in internally insulated ducts than in uninsulated steel ducts. In most cases, deposition in straight ducts with developing turbulence, in duct bends and at S-connectors at duct junctions was higher than in straight ducts with fully developed turbulence. Measured deposition rates were generally higher than predicted by published models. A model incorporating empirical equations based on

  9. Exercise for falls prevention in Parkinson disease

    PubMed Central

    Sherrington, Catherine; Lord, Stephen R.; Close, Jacqueline C.T.; Heritier, Stephane; Heller, Gillian Z.; Howard, Kirsten; Allen, Natalie E.; Latt, Mark D.; Murray, Susan M.; O'Rourke, Sandra D.; Paul, Serene S.; Song, Jooeun; Fung, Victor S.C.

    2015-01-01

    Objective: To determine whether falls can be prevented with minimally supervised exercise targeting potentially remediable fall risk factors, i.e., poor balance, reduced leg muscle strength, and freezing of gait, in people with Parkinson disease. Methods: Two hundred thirty-one people with Parkinson disease were randomized into exercise or usual-care control groups. Exercises were practiced for 40 to 60 minutes, 3 times weekly for 6 months. Primary outcomes were fall rates and proportion of fallers during the intervention period. Secondary outcomes were physical (balance, mobility, freezing of gait, habitual physical activity), psychological (fear of falling, affect), and quality-of-life measures. Results: There was no significant difference between groups in the rate of falls (incidence rate ratio [IRR] = 0.73, 95% confidence interval [CI] 0.45–1.17, p = 0.18) or proportion of fallers (p = 0.45). Preplanned subgroup analysis revealed a significant interaction for disease severity (p < 0.001). In the lower disease severity subgroup, there were fewer falls in the exercise group compared with controls (IRR = 0.31, 95% CI 0.15–0.62, p < 0.001), while in the higher disease severity subgroup, there was a trend toward more falls in the exercise group (IRR = 1.61, 95% CI 0.86–3.03, p = 0.13). Postintervention, the exercise group scored significantly (p < 0.05) better than controls on the Short Physical Performance Battery, sit-to-stand, fear of falling, affect, and quality of life, after adjusting for baseline performance. Conclusions: An exercise program targeting balance, leg strength, and freezing of gait did not reduce falls but improved physical and psychological health. Falls were reduced in people with milder disease but not in those with more severe Parkinson disease. Classification of evidence: This study provides Class III evidence that for patients with Parkinson disease, a minimally supervised exercise program does not reduce fall risk. This study lacked

  10. Euramerican tonsteins: overview, magmatic origin, and depositional-tectonic implications

    USGS Publications Warehouse

    Lyons, P.C.; Spears, D.A.; Outerbridge, W.F.; Congdon, R.D.; Evans, H.T.

    1994-01-01

    Carboniferous tonsteins (kaolinized volcanic-ash beds) of wide geographic distribution are known in both Europe and North America. Relict volcanic minerals common in these Euramerican tonsteins are volcanic quartz (including beta-quartz paramorphs), zircon and ilmenite; less common are magnetite, fayalite, rutile, monazite, xenotime, apatite and sanidine. Data for two relatively thick (3-13 cm) and widespread (>400 km) European tonsteins (Erda and Sub-Worsley Four-foot) indicate an increase in detrital quartz near the top of the beds which indicates mixing with normal clastic sediments, including the introduction of heavy detrital minerals (e.g., tourmaline and garnet). These thick tonsteins show multiple horizontal bedding, normal graded bedding, disturbed bedding, and centimeter-scale scour surfaces. The Fire Clay tonstein in North America represents from one to five separate volcanic air-fall ash deposits as determined by normal graded bedding and mineralogical analysis. These features indicate several episodes of volcanic-ash deposition and very localized subsequent erosion and bioturbation. Electron microprobe data from glass inclusions in volcanic quartz in Euramerican tonsteins indicate a rhyolitic origin for these tonsteins and reveal chemical "fingerprints" valuable for intra- and inter-basinal correlations. However, the tectonic framework for European and North American tonsteins was quite different. In Europe, volcanic-ash beds were associated with Variscan collisional tectonics, whereas in North America, volcanic ash was associated with Ouachita tectonic activity, explosive volcanism from the Yucatan block, collision between the South American and North American plates, and the formation of Pangea. ?? 1994.

  11. Nitrogen and sulfur deposition on regional and global scales: A multimodel evaluation

    NASA Astrophysics Data System (ADS)

    Dentener, F.; Drevet, J.; Lamarque, J. F.; Bey, I.; Eickhout, B.; Fiore, A. M.; Hauglustaine, D.; Horowitz, L. W.; Krol, M.; Kulshrestha, U. C.; Lawrence, M.; Galy-Lacaux, C.; Rast, S.; Shindell, D.; Stevenson, D.; van Noije, T.; Atherton, C.; Bell, N.; Bergman, D.; Butler, T.; Cofala, J.; Collins, B.; Doherty, R.; Ellingsen, K.; Galloway, J.; Gauss, M.; Montanaro, V.; Müller, J. F.; Pitari, G.; Rodriguez, J.; Sanderson, M.; Solmon, F.; Strahan, S.; Schultz, M.; Sudo, K.; Szopa, S.; Wild, O.

    2006-12-01

    We use 23 atmospheric chemistry transport models to calculate current and future (2030) deposition of reactive nitrogen (NOy, NHx) and sulfate (SOx) to land and ocean surfaces. The models are driven by three emission scenarios: (1) current air quality legislation (CLE); (2) an optimistic case of the maximum emissions reductions currently technologically feasible (MFR); and (3) the contrasting pessimistic IPCC SRES A2 scenario. An extensive evaluation of the present-day deposition using nearly all information on wet deposition available worldwide shows a good agreement with observations in Europe and North America, where 60-70% of the model-calculated wet deposition rates agree to within ±50% with quality-controlled measurements. Models systematically overestimate NHx deposition in South Asia, and underestimate NOy deposition in East Asia. We show that there are substantial differences among models for the removal mechanisms of NOy, NHx, and SOx, leading to ±1 σ variance in total deposition fluxes of about 30% in the anthropogenic emissions regions, and up to a factor of 2 outside. In all cases the mean model constructed from the ensemble calculations is among the best when comparing to measurements. Currently, 36-51% of all NOy, NHx, and SOx is deposited over the ocean, and 50-80% of the fraction of deposition on land falls on natural (nonagricultural) vegetation. Currently, 11% of the world's natural vegetation receives nitrogen deposition in excess of the "critical load" threshold of 1000 mg(N) m-2 yr-1. The regions most affected are the United States (20% of vegetation), western Europe (30%), eastern Europe (80%), South Asia (60%), East Asia (40%), southeast Asia (30%), and Japan (50%). Future deposition fluxes are mainly driven by changes in emissions, and less importantly by changes in atmospheric chemistry and climate. The global fraction of vegetation exposed to nitrogen loads in excess of 1000 mg(N) m-2 yr-1 increases globally to 17% for CLE and 25% for

  12. How Much Atmospheric Deposition Across the US: Comparison of N and S Deposition Estimates

    NASA Astrophysics Data System (ADS)

    Weathers, K. C.; Lynch, J. A.

    2008-12-01

    Despite decades of research and monitoring efforts, generating accurate measurements of total (wet + dry) atmospheric deposition across heterogeneous landscapes is still a challenge. In addition, there have been two major, national scale approaches used for generating nitrogen (N) and sulfur (S) deposition across the US. There are two monitoring sources that, when combined with deposition models, result in S and N input estimates. Here we compare N and S total deposition as modeled using the (1) Community Multiscale Air Quality (CMAQ) modeling system, which uses air emissions data combined with chemical transformations, meterologic, and land cover data in a mechanistic model, and (2) the sum of the Clean Air Status and Trends (CASTNET) air chemistry and modeling program data for dry deposition and wet deposition estimates from the National Atmospheric Deposition Program (NADP). Here we examine wet, dry and total deposition estimates based on these two approaches. Overall, estimates of wet deposition of S and N comparisons showed close agreement (r2 = 0.79 to 0.83) while estimates of dry deposition based on the two approaches varied considerably (r2 = 0.25 to 0.67). Relative to deposition measured at NADP sites, CMAQ values slightly over represented wet sulfate deposition, but slightly underrepresented wet nitrate and ammonium input. However, CMAQ-estimated dry deposition of nitric acid was much higher than CASTNET-estimated deposition, while dry ammonium and nitrate were much lower using the CMAQ model. When compared spatially, regions that showed large differences in total N and S deposition included the Midwest and west central Appalachian mountains, showing differences of up to 6kgN or S/ha/yr.

  13. 32 CFR 807.6 - Depositing payments.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 6 2011-07-01 2011-07-01 false Depositing payments. 807.6 Section 807.6 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE ADMINISTRATION SALE TO THE PUBLIC § 807.6 Depositing payments. Obtain instructions from the local Accounting and Finance...

  14. 32 CFR 807.6 - Depositing payments.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 6 2010-07-01 2010-07-01 false Depositing payments. 807.6 Section 807.6 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE ADMINISTRATION SALE TO THE PUBLIC § 807.6 Depositing payments. Obtain instructions from the local Accounting and Finance...

  15. Unexplained Falls Are Frequent in Patients with Fall-Related Injury Admitted to Orthopaedic Wards: The UFO Study (Unexplained Falls in Older Patients).

    PubMed

    Chiara, Mussi; Gianluigi, Galizia; Pasquale, Abete; Alessandro, Morrione; Alice, Maraviglia; Gabriele, Noro; Paolo, Cavagnaro; Loredana, Ghirelli; Giovanni, Tava; Franco, Rengo; Giulio, Masotti; Gianfranco, Salvioli; Niccolò, Marchionni; Andrea, Ungar

    2013-01-01

    To evaluate the incidence of unexplained falls in elderly patients affected by fall-related fractures admitted to orthopaedic wards, we recruited 246 consecutive patients older than 65 (mean age 82 ± 7 years, range 65-101). Falls were defined "accidental" (fall explained by a definite accidental cause), "medical" (fall caused directly by a specific medical disease), "dementia-related" (fall in patients affected by moderate-severe dementia), and "unexplained" (nonaccidental falls, not related to a clear medical or drug-induced cause or with no apparent cause). According to the anamnestic features of the event, older patients had a lower tendency to remember the fall. Patients with accidental fall remember more often the event. Unexplained falls were frequent in both groups of age. Accidental falls were more frequent in younger patients, while dementia-related falls were more common in the older ones. Patients with unexplained falls showed a higher number of depressive symptoms. In a multivariate analysis a higher GDS and syncopal spells were independent predictors of unexplained falls. In conclusion, more than one third of all falls in patients hospitalized in orthopaedic wards were unexplained, particularly in patients with depressive symptoms and syncopal spells. The identification of fall causes must be evaluated in older patients with a fall-related injury. PMID:23533394

  16. Unexplained Falls Are Frequent in Patients with Fall-Related Injury Admitted to Orthopaedic Wards: The UFO Study (Unexplained Falls in Older Patients).

    PubMed

    Chiara, Mussi; Gianluigi, Galizia; Pasquale, Abete; Alessandro, Morrione; Alice, Maraviglia; Gabriele, Noro; Paolo, Cavagnaro; Loredana, Ghirelli; Giovanni, Tava; Franco, Rengo; Giulio, Masotti; Gianfranco, Salvioli; Niccolò, Marchionni; Andrea, Ungar

    2013-01-01

    To evaluate the incidence of unexplained falls in elderly patients affected by fall-related fractures admitted to orthopaedic wards, we recruited 246 consecutive patients older than 65 (mean age 82 ± 7 years, range 65-101). Falls were defined "accidental" (fall explained by a definite accidental cause), "medical" (fall caused directly by a specific medical disease), "dementia-related" (fall in patients affected by moderate-severe dementia), and "unexplained" (nonaccidental falls, not related to a clear medical or drug-induced cause or with no apparent cause). According to the anamnestic features of the event, older patients had a lower tendency to remember the fall. Patients with accidental fall remember more often the event. Unexplained falls were frequent in both groups of age. Accidental falls were more frequent in younger patients, while dementia-related falls were more common in the older ones. Patients with unexplained falls showed a higher number of depressive symptoms. In a multivariate analysis a higher GDS and syncopal spells were independent predictors of unexplained falls. In conclusion, more than one third of all falls in patients hospitalized in orthopaedic wards were unexplained, particularly in patients with depressive symptoms and syncopal spells. The identification of fall causes must be evaluated in older patients with a fall-related injury.

  17. Adsorption and transport of gas-phase naphthalene on micron-size fog droplets in air.

    PubMed

    Raja, Suresh; Valsaraj, Kalliat T

    2004-02-01

    Aromatic hydrocarbon vapors adsorb to the air/water interface and are transported by wet deposition processes via fog, mist, and rain. A falling droplet apparatus was used to study the adsorption and uptake of naphthalene vapor on water droplets with diameters ranging from 14 to 200 microm. Uptake of naphthalene vapor greater than that predicted by bulk (air-water) phase equilibrium was noted for diameters less than 50 microm and was attributed to surface adsorption. The experimental values of the droplet-vapor partition constants were used to obtain the mass accommodation coefficient for naphthalene at the interface. The effect of temperature on the mass accommodation coefficientwas measured. The effects of a synthetic surfactant and a natural organic carbon surrogate (Suwanee Fulvic acid) on the uptake of naphthalene vapors on water droplets were also examined. Small droplet diameter, decreased temperature, and the presence of dissolved surface-active material in water enhanced the uptake of naphthalene into fog droplets.

  18. Falls Prevention: Unique to Older Adults

    MedlinePlus

    ... Prevention Sleep Problems Stroke Join our e-newsletter! Aging & Health A to Z Falls Prevention Unique to ... difficulties. Optimizing Management of Congestive Heart Failure and COPD Congestive Heart Failure (CHF) Many older people develop ...

  19. Falls Among Older Adults: An Overview

    MedlinePlus

    ... and no handrails along stairs or in the bathroom. Most falls are caused by a combination of ... online]. Accessed August 15, 2013. National Hospital Discharge Survey (NHDS), National Center for Health Statistics. Health Data ...

  20. Ocular problems in military free fall parachutists.

    PubMed

    Gruppo, Leonard; Mader, Thomas H; Wedmore, Ian

    2002-10-01

    Military free fall parachutists may be unaware of the risk of corneal freezing and desiccation keratitis should their goggles come off during free fall in subfreezing temperatures. We determine the incidence of ocular difficulties in military free fall parachutists and the role freezing temperatures may play in causing these problems. We found that 79% of those who responded to the survey had lost their goggles at least once during free fall and 69% experienced ocular symptoms after goggle loss. Analysis shows a 30-fold increase in the duration of symptoms in subfreezing vs. above-freezing temperatures, with the odds of the ground mission being affected at 7.3 per 100 jumps in the subfreezing group. The rate of goggles coming off per jump is 3.3 times less with >75 jumps. Contact lenses are not protective and photorefractive keratectomy was not detrimental. PMID:12392242

  1. Siena, 1794: History's Most Consequential Meteorite Fall

    NASA Astrophysics Data System (ADS)

    Marvin, U. B.

    1995-09-01

    In the mythos of meteoritics, the fall of stones at L'Aigle in Normandy at 1 p. m. on April 26, 1803, is commonly regarded as the event that turned skeptics into believers and opened the way for the new science. A strong case can be made, however, that the fall of stones at Siena at 7:00 p.m. on June 16, 1794, established the authenticity of meteorite falls and set in motion the reexaminations of entrenched beliefs that led to the founding of the new science. The Siena fall was heralded by the appearance of an extraordinarily high, dark cloud emitting smoke, sparks like rockets, and bolts of unusually slow-moving red lightning. With a tremendous explosion a shower of stones, ranging in weight from a few milligrams to 3 kg, fell southeast of Siena. This was the first meteorite fall to occur in the vicinity of a sizeable European city and the first to be witnessed by so many people, including English visitors, that the fall of the stones from the sky could not be denied. It also was the first fall to be seriously investigated by scholars, at several universities in Italy, who collected eye-witness reports and specimens and formulated hypotheses of origin. Their task was greatly complicated by the timing of the fall which occurred 18 hours after Mt. Vesuvius sprang into full eruption. Some believed that the two events were entirely coincidental; others thought that the stones either were ejecta from the volcano (which lay about 320 km to the southeast of Siena) or had consolidated in the fiery masses of dust and ash expelled by the mountain. No explanations seemed entirely satisfactory, but, in an age when the very possibility of falling stones had been decisively ruled out by savants of the Enlightenment, the well-observed fall at Siena opened a new dialog on this subject. The Siena fall occurred only two months after the publication in Riga and Leipzig of Ernst F. F. Chladni's book On the Origin of Ironmasses in which he concluded from historical records that

  2. Effect of free fall on higher plants.

    NASA Technical Reports Server (NTRS)

    Gordon, S. A.

    1973-01-01

    The influence of exposure to the free-fall state on the orientation, morphogenesis, physiology, and radiation response of higher plants is briefly summarized. It is proposed that the duration of the space-flight experiments has been to brief to permit meaningful effects of free fall on general biochemistry, growth, and development to appear. However, two types of significant effect did occur. The first is on differential growth - i.e., tropism and epinasty - resulting from the absence of a normal geostimulus. For these phenomena it is suggested that ground-based experiments with the clinostat would suffice to mimic the effect of the free-fall state. The second is an apparent interaction between the radiation response and some flight condition, yielding an enhanced microspore abortion, a disturbed spindle function, and a stunting of stamen hairs. It is suggested that this apparent interaction may be derived from a shift in the rhythm of the cell cycle, induced by the free fall.

  3. Enhanced nitrogen deposition over China.

    PubMed

    Liu, Xuejun; Zhang, Ying; Han, Wenxuan; Tang, Aohan; Shen, Jianlin; Cui, Zhenling; Vitousek, Peter; Erisman, Jan Willem; Goulding, Keith; Christie, Peter; Fangmeier, Andreas; Zhang, Fusuo

    2013-02-28

    China is experiencing intense air pollution caused in large part by anthropogenic emissions of reactive nitrogen. These emissions result in the deposition of atmospheric nitrogen (N) in terrestrial and aquatic ecosystems, with implications for human and ecosystem health, greenhouse gas balances and biological diversity. However, information on the magnitude and environmental impact of N deposition in China is limited. Here we use nationwide data sets on bulk N deposition, plant foliar N and crop N uptake (from long-term unfertilized soils) to evaluate N deposition dynamics and their effect on ecosystems across China between 1980 and 2010. We find that the average annual bulk deposition of N increased by approximately 8 kilograms of nitrogen per hectare (P < 0.001) between the 1980s (13.2 kilograms of nitrogen per hectare) and the 2000s (21.1 kilograms of nitrogen per hectare). Nitrogen deposition rates in the industrialized and agriculturally intensified regions of China are as high as the peak levels of deposition in northwestern Europe in the 1980s, before the introduction of mitigation measures. Nitrogen from ammonium (NH4(+)) is the dominant form of N in bulk deposition, but the rate of increase is largest for deposition of N from nitrate (NO3(-)), in agreement with decreased ratios of NH3 to NOx emissions since 1980. We also find that the impact of N deposition on Chinese ecosystems includes significantly increased plant foliar N concentrations in natural and semi-natural (that is, non-agricultural) ecosystems and increased crop N uptake from long-term-unfertilized croplands. China and other economies are facing a continuing challenge to reduce emissions of reactive nitrogen, N deposition and their negative effects on human health and the environment. PMID:23426264

  4. Enhanced nitrogen deposition over China.

    PubMed

    Liu, Xuejun; Zhang, Ying; Han, Wenxuan; Tang, Aohan; Shen, Jianlin; Cui, Zhenling; Vitousek, Peter; Erisman, Jan Willem; Goulding, Keith; Christie, Peter; Fangmeier, Andreas; Zhang, Fusuo

    2013-02-28

    China is experiencing intense air pollution caused in large part by anthropogenic emissions of reactive nitrogen. These emissions result in the deposition of atmospheric nitrogen (N) in terrestrial and aquatic ecosystems, with implications for human and ecosystem health, greenhouse gas balances and biological diversity. However, information on the magnitude and environmental impact of N deposition in China is limited. Here we use nationwide data sets on bulk N deposition, plant foliar N and crop N uptake (from long-term unfertilized soils) to evaluate N deposition dynamics and their effect on ecosystems across China between 1980 and 2010. We find that the average annual bulk deposition of N increased by approximately 8 kilograms of nitrogen per hectare (P < 0.001) between the 1980s (13.2 kilograms of nitrogen per hectare) and the 2000s (21.1 kilograms of nitrogen per hectare). Nitrogen deposition rates in the industrialized and agriculturally intensified regions of China are as high as the peak levels of deposition in northwestern Europe in the 1980s, before the introduction of mitigation measures. Nitrogen from ammonium (NH4(+)) is the dominant form of N in bulk deposition, but the rate of increase is largest for deposition of N from nitrate (NO3(-)), in agreement with decreased ratios of NH3 to NOx emissions since 1980. We also find that the impact of N deposition on Chinese ecosystems includes significantly increased plant foliar N concentrations in natural and semi-natural (that is, non-agricultural) ecosystems and increased crop N uptake from long-term-unfertilized croplands. China and other economies are facing a continuing challenge to reduce emissions of reactive nitrogen, N deposition and their negative effects on human health and the environment.

  5. Characteristics Of Atmospheric Dry Deposition Of Metals To The Region Of Lake Asan And Sapgyo, Korea

    NASA Astrophysics Data System (ADS)

    Han, J.; Shin, H.; Lee, M.; Lim, Y.; Seo, M.; Jung, I.

    2008-12-01

    Environment includes a multi-media such as air, surface water, soil, underground water and ecosystem. Some pollutants transfer among a multi-media, posing serious threat to humans, animals and plants. Pollutants released into the environment remain for long times and transport long distances while going through physical and chemical interactions such as transports between multi-media ; air, water and soil, deposition, and absorption and release from organisms. This study assessed the amount of heavy metals transferred from air to water and soil using dry deposition plate and water surface sampler during spring (June 13 ~ 21, 2007) and winter (October 23 ~ 30 in 2007) at 9 locations including Dangjin, Pyeongtaek and Asan. Micro-Orifice Uniform Deposit Impactor, MOUDI was used to confirm the size distribution. The measured heavy metal deposition flux was compared with the expectation obtained with deposition model. In addition, amount of heavy metal deposition at Asan and Sapgyo lakes were evaluated to verify the water pollution state driven by atmospheric deposition. Atmospheric dry deposition flux of metals are 133.92 microgram m-2 day-1, 44.01 microgram m-2 day-1, 0.915 microgram m-2 day-1, and 0.175 microgram m-2 day-1 during spring, and 72.86 microgram m-2 day- 1, 88.14 microgram m-2 day-1, 0.991 microgram m-2 day-1, and 0.189 microgram m-2 day-1 during fall, for lead, nickel, arsenic, and cadmium, respectively. It is required to re- calculation the dry deposition flux by land use type due to possibility of underestimating the flux in case of using grease surrogate surface having low surface roughness. The cadmium, lead, and arsenic size distribution was mono-modal with the peaks in the 0.65 ~ 1.1 micrometer size range in the fine mode showing sharp peak in the condensation submode especially for cadmium and lead because of effect of primary emission. The nickel size distribution was bimodal, a typical size distribution for an urban atmosphere, showing sharp

  6. Soot Deposit Properties in Practical Flames

    SciTech Connect

    Preciado, Ignacio; Eddings, Eric G.; Sarofim, Adel F.; Dinwiddie, Ralph Barton; Porter, Wallace D; Lance, Michael J

    2009-01-01

    Soot deposition from hydrocarbon flames was investigated in order to evaluate the evolution of the deposits during the transient process of heating an object that starts with a cold metal surface that is exposed to a flame. The study focused on the fire/metal surface interface and the critical issues associated with the specification of the thermal boundaries at this interface, which include the deposition of soot on the metal surface, the chemical and physical properties of the soot deposits and their subsequent effect on heat transfer to the metal surface. A laboratory-scale device (metallic plates attached to a water-cooled sampling probe) was designed for studying soot deposition in a laminar ethylene-air premixed flame. The metallic plates facilitate the evaluation of the deposition rates and deposit characteristics such as deposit thickness, bulk density, PAH content, deposit morphology, and thermal properties, under both water-cooled and uncooled conditions. Additionally, a non-intrusive Laser Flash Technique (in which the morphology of the deposit is not modified) was used to estimate experimental thermal conductivity values for soot deposits as a function of deposition temperature (water-cooled and uncooled experiments), location within the flame and chemical characteristics of the deposits. Important differences between water-cooled and uncooled surfaces were observed. Thermophoresis dominated the soot deposition process and enhanced higher deposition rates for the water-cooled experiments. Cooler surface temperatures resulted in the inclusion of increased amounts of condensable hydrocarbons in the soot deposit. The greater presence of condensable material promoted decreased deposit thicknesses, larger deposit densities, different deposit morphologies, and higher thermal conductivities.

  7. 158. Photocopy of transit book (taken from Twin Falls Canal ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    158. Photocopy of transit book (taken from Twin Falls Canal Company Transit Book #404T, Page 3, #46, Division One). START OF MAIN CANAL SURVEY, TWIN FALLS COUNTY, MILNER, IDAHO. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

  8. 155. Photocopy of transit book (taken from Twin Falls Canal ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    155. Photocopy of transit book (taken from Twin Falls Canal Company Surveyor's Transit Book #405T, Page 1, #46 Division One). STATEMENT RE: SURVEY ALIGNMENT 3/03, TWIN FALLS COUNTY, MILNER, IDAHO. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

  9. 154. Photocopy of transit book (taken from Twin Falls Canal ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    154. Photocopy of transit book (taken from Twin Falls Canal Company Surveyor's Transit Book #405T, Page 2, #46 Division One). STATEMENT OF SIGHT-SETTING FOR 1903 SURVEY TO ALIGN SOUTH SIDE CANAL, TWIN FALLS COUNTY, MILNER, IDAHO. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

  10. Estimation of the kinetic energy dissipation in fall-arrest system and manikin during fall impact.

    PubMed

    Wu, John Z; Powers, John R; Harris, James R; Pan, Christopher S

    2011-04-01

    Fall-arrest systems (FASs) have been widely applied to provide a safe stop during fall incidents for occupational activities. The mechanical interaction and kinetic energy exchange between the human body and the fall-arrest system during fall impact is one of the most important factors in FAS ergonomic design. In the current study, we developed a systematic approach to evaluate the energy dissipated in the energy absorbing lanyard (EAL) and in the harness/manikin during fall impact. The kinematics of the manikin and EAL during the impact were derived using the arrest-force time histories that were measured experimentally. We applied the proposed method to analyse the experimental data of drop tests at heights of 1.83 and 3.35 m. Our preliminary results indicate that approximately 84-92% of the kinetic energy is dissipated in the EAL system and the remainder is dissipated in the harness/manikin during fall impact. The proposed approach would be useful for the ergonomic design and performance evaluation of an FAS. STATEMENT OF RELEVANCE: Mechanical interaction, especially kinetic energy exchange, between the human body and the fall-arrest system during fall impact is one of the most important factors in the ergonomic design of a fall-arrest system. In the current study, we propose an approach to quantify the kinetic energy dissipated in the energy absorbing lanyard and in the harness/body system during fall impact.

  11. Validation of the Saskatoon Falls Prevention Consortium's Falls Screening and Referral Algorithm

    PubMed Central

    Lawson, Sara Nicole; Zaluski, Neal; Petrie, Amanda; Arnold, Cathy; Basran, Jenny

    2013-01-01

    ABSTRACT Purpose: To investigate the concurrent validity of the Saskatoon Falls Prevention Consortium's Falls Screening and Referral Algorithm (FSRA). Method: A total of 29 older adults (mean age 77.7 [SD 4.0] y) residing in an independent-living senior's complex who met inclusion criteria completed a demographic questionnaire and the components of the FSRA and Berg Balance Scale (BBS). The FSRA consists of the Elderly Fall Screening Test (EFST) and the Multi-factor Falls Questionnaire (MFQ); it is designed to categorize individuals into low, moderate, or high fall-risk categories to determine appropriate management pathways. A predictive model for probability of fall risk, based on previous research, was used to determine concurrent validity of the FSRI. Results: The FSRA placed 79% of participants into the low-risk category, whereas the predictive model found the probability of fall risk to range from 0.04 to 0.74, with a mean of 0.35 (SD 0.25). No statistically significant correlation was found between the FSRA and the predictive model for probability of fall risk (Spearman's ρ=0.35, p=0.06). Conclusion: The FSRA lacks concurrent validity relative to to a previously established model of fall risk and appears to over-categorize individuals into the low-risk group. Further research on the FSRA as an adequate tool to screen community-dwelling older adults for fall risk is recommended. PMID:24381379

  12. Simulated unobtrusive falls detection with multiple persons.

    PubMed

    Ariani, Arni; Redmond, Stephen J; Chang, David; Lovell, Nigel H

    2012-11-01

    One serious issue related to falls among the elderly living at home or in a residential care facility is the "long lie" scenario, which involves being unable to get up from the floor after a fall for 60 min or more. This research uses a simulated environment to investigate the potential effectiveness of using wireless ambient sensors (dual-technology (microwave/infrared) motion detectors and pressure mats) to track the movement of multiple persons and to unobtrusively detect falls when they occur, therefore reducing the rate of occurrence of "long lie" scenarios. A path-finding algorithm (A*) is used to simulate the movement of one or more persons through the residential area. For analysis, the sensor network is represented as an undirected graph, where nodes in the graph represent sensors, and edges between nodes in the graph imply that these sensors share an overlapping physical region in their area of sensitivity. A second undirected graph is used to represent the physical adjacency of the sensors (even where they do not overlap in their monitored regions). These graphical representations enable the tracking of multiple subjects/groups within the environment, by analyzing the sensor activation and adjacency profiles, hence allowing individuals/groups to be isolated when multiple persons are present, and subsequently monitoring falls events. A falls algorithm, based on a heuristic decision tree classifier model, was tested on 15 scenarios, each including one or more persons; three scenarios of activity of daily living, and 12 different types of falls (four types of fall, each with three postfall scenarios). The sensitivity, specificity, and accuracy of the falls algorithm are 100.00%, 77.14%, and 89.33%, respectively. PMID:22835529

  13. Simulated unobtrusive falls detection with multiple persons.

    PubMed

    Ariani, Arni; Redmond, Stephen J; Chang, David; Lovell, Nigel H

    2012-11-01

    One serious issue related to falls among the elderly living at home or in a residential care facility is the "long lie" scenario, which involves being unable to get up from the floor after a fall for 60 min or more. This research uses a simulated environment to investigate the potential effectiveness of using wireless ambient sensors (dual-technology (microwave/infrared) motion detectors and pressure mats) to track the movement of multiple persons and to unobtrusively detect falls when they occur, therefore reducing the rate of occurrence of "long lie" scenarios. A path-finding algorithm (A*) is used to simulate the movement of one or more persons through the residential area. For analysis, the sensor network is represented as an undirected graph, where nodes in the graph represent sensors, and edges between nodes in the graph imply that these sensors share an overlapping physical region in their area of sensitivity. A second undirected graph is used to represent the physical adjacency of the sensors (even where they do not overlap in their monitored regions). These graphical representations enable the tracking of multiple subjects/groups within the environment, by analyzing the sensor activation and adjacency profiles, hence allowing individuals/groups to be isolated when multiple persons are present, and subsequently monitoring falls events. A falls algorithm, based on a heuristic decision tree classifier model, was tested on 15 scenarios, each including one or more persons; three scenarios of activity of daily living, and 12 different types of falls (four types of fall, each with three postfall scenarios). The sensitivity, specificity, and accuracy of the falls algorithm are 100.00%, 77.14%, and 89.33%, respectively.

  14. Fatal falls: lessons for the future.

    PubMed

    2000-07-12

    Health care organizations that have experienced sentinel events due to falls have identified the root causes and risk reduction strategies included in this issue. In addition, experts have commented on the events and the related root causes and risk reduction strategies. The Joint Commission offers this information for consideration by hospitals, long term care facilities and behavioral health care organizations in their continuing efforts to reduce the risk of falls of their patients, residents or individuals served.

  15. Quantifying Temperature Effects on Fall Chinook Salmon

    SciTech Connect

    Jager, Yetta

    2011-11-01

    The motivation for this study was to recommend relationships for use in a model of San Joaquin fall Chinook salmon. This report reviews literature pertaining to relationships between water temperature and fall Chinook salmon. The report is organized into three sections that deal with temperature effects on development and timing of freshwater life stages, temperature effects on incubation survival for eggs and alevin, and temperature effects on juvenile survival. Recommendations are made for modeling temperature influences for all three life stages.

  16. Get connected: New Fall Meeting technology

    NASA Astrophysics Data System (ADS)

    Moscovitch, Mirelle

    2012-11-01

    Kick off your 2012 Fall Meeting experience today by joining the Fall Meeting Community, an interactive Web-based community. Whether you are attending this year's Fall Meeting or are just interested in learning more, this site can help you connect with colleagues, learn about the groundbreaking research and amazing programming being presented in San Francisco, and plan your trip to the largest Earth and space science conference of the year. Available through the Fall Meeting Web site (http://fallmeeting.agu.org), the Community allows you to share your Fall Meeting experience like never before. You can join groups based on your interests, and each group includes a message board that allows you to ask questions, post comments, discuss presentations, and make plans with colleagues. You can also create your own groups and use the Community's robust search engine to find and connect with friends. And because the Fall Meeting Web site was improved for 2012 to allow for nearly seamless functionality on mobile devices, you can access much of the same Community functionality on the go.

  17. Prevalence of falls in fibromyalgia patients

    PubMed Central

    Meireles, Sandra Adolph; Antero, Daniel Casagrande; Kulczycki, Marciane Maria; Skare, Thelma Larocca

    2014-01-01

    OBJECTIVE: To compare the risk of falls in fibromyalgia (FM) patients compared to rheumatoid arthritis (RA) patients and normal controls. METHODS: We studied 60 FM, 60 RA patients and 60 controls for fall frequency in one week, one month, six months and one year. Patients were submitted to body mass index determination and balance evaluation through the Berg scale. Data on disease impact and depression were collected in FM patients through the Fibromyalgia Impact Questionnaire (FIQ) and the Beck Questionnaire. RESULTS: FM patients had a higher frequency of falls than RA patients and control individuals in one month (p<0.0001), in six months (p<0.0001) and in one year (p<0.0001). No relationship was found between falls and body mass index, pain or depression scores. Falls in 12 months were associated with higher FIQ values. CONCLUSION: FM patients fall more often than RA patients and control individuals. Level of Evidence II, Investigation of the effect of a patient characteristic on the disease outcome. PMID:25061425

  18. Mid-Cretaceous Eustatic sea level fall: magnitude and timing in Gulf of Mexico

    SciTech Connect

    Vierbuchen, R.C.; Oestmann, M.A.; Greenlee, S.M.

    1987-05-01

    The magnitude and timing of a mid-Cretaceous sea level fall have been documented on the margins of the Gulf of Mexico in east Texas. Analysis of seismic, log, and paleontologic data from east Texas demonstrates that a fall of 60 to 100 m occurred at the end of Washita (mid-Cenomanian) time. This sea level fall has been identified elsewhere on the shelves of the Gulf of Mexico and is proposed to have caused the mid-Cretaceous unconformity of the deep sea and the termination of Washita carbonate deposition. They conclude that this sea level fall is of regional significance and eustatic origin. The magnitude and timing of the fall agree with those postulated by Vail and others, and Haq and others, who recognized a major sea level fall in mid-Cenomanian time. The magnitude of sea level fall is estimated from the difference in elevation between carbonate buildups on the Buda margin, which accumulated at or near sea level, and fluvial deposits in the lower Woodbine, which immediately overlie Buda carbonates and have been drilled up to 20 km basinward of the shelf margin. After constructing a datum along the preexisting Buda shelf, they measure the thickness of sediment from this datum to the onlapping fluvial, lower Woodbine siliciclastics. This measurement is then corrected for compaction, isostatic subsidence due to sediment loading, and thermotectonic subsidence. The result, 60 m, is considered a minimum estimate. A similar measurement to the lowest seismically identified coastal onlap in the lower Woodbine yields an estimate of 100 m.

  19. RESULTS FROM THE MOUNTAIN ACID DEPOSITION PROGRAM

    EPA Science Inventory

    The Mountain Acid Deposition Program (MADPro) was initiated in 1993 as part of the research necessary to support the objectives of the Clean Air Status and Trends Network (CASTNet), which was created to address the. requirements of the Clean Air Act Amendments (CAAA). The main ob...

  20. Landslides caused by the Klamath Falls, Oregon, earthquakes of September 20, 1993

    USGS Publications Warehouse

    Keefer, D.K.; Schuster, R.L.

    1993-01-01

    In the Klamath Falls area, the most numerous earthquake-induced rock falls were along the east-to southeast-facing flank of a ridge immediately south and west of Howard Bay (locality 1 on the accompanying map), 18 km east-southeast of the epicenter of the magntiude 6.0 shock at 10:45 p.m. This ridge is more than 240 m high and has slopes steeper than 45° in places. The upper part of the ridge is composed of material from basaltic lava flows, an the lower slopes are covered with colluvium and talus deposits containing abundant boulders. 

  1. Central and Peripheral Visual Impairment and the Risk of Falls and Falls with Injury

    PubMed Central

    Patino, Cecilia M.; McKean-Cowdin, Roberta; Azen, Stanley P.; Allison, Jessica Chung; Choudhury, Farzana; Varma, Rohit

    2009-01-01

    Objective To evaluate central and peripheral visual impairment as independent risk factors for falls and falls with injury among adults. Design Population-based prospective cohort study. Participants A total of 3,203 LALES participants. Methods Baseline presenting binocular central distance acuity was measured and impairment was classified as mild (20/40–20/63), moderate/severe (20/80 or worse). Peripheral visual impairment was classified as mild (−6dBFalls and falls with injury in the past 12 months were assessed by self-report at 4-year follow-up visit. Results Out of 3,203 individuals, 19% reported falls and 10% falls with injury; participants with falls were more likely to: be ≥ 60 years of age, be female, report lower income, have more than two co-morbidities, report alcohol use, report wearing bifocal glasses and report obesity. Among those who reported falls, 7% had central visual impairment (visual acuity≥20/40) compared to 4% who did not report falls; and 49% had peripheral visual impairment (mean deviation<−2dB) compared to 39% of those who did not report falls (both p-values<.0001). After adjusting for confounders, moderate to severe central and peripheral visual impairment were associated with increased risk for falls (odds ratio 2.36 95% confidence interval 1.02–5.45, p-trend= .04 and odds ratio 1.42 95% confidence interval 1.06–1.91, p-trend= .01, respectively) and with falls with injury (odds ratio 2.76 95% confidence interval 1.10–7.02, p-value= .03, and odds ratio 1.40 95% confidence interval .94–2.05, p-trend= .04, respectively). Conclusion Both central and peripheral visual impairment were independently associated with increased risk for falls and falls with injury in a dose-response manner. Although vision related interventions for preventing falls have mainly focused on correcting central visual impairment, this

  2. Comparison of real-life accidental falls in older people with experimental falls in middle-aged test subjects.

    PubMed

    Kangas, M; Vikman, I; Nyberg, L; Korpelainen, R; Lindblom, J; Jämsä, T

    2012-03-01

    Falling is a common accident among older people. Automatic fall detectors are one method of improving security. However, in most cases, fall detectors are designed and tested with data from experimental falls in younger people. This study is one of the first to provide fall-related acceleration data obtained from real-life falls. Wireless sensors were used to collect acceleration data during a six-month test period in older people. Data from five events representing forward falls, a sideways fall, a backwards fall, and a fall out of bed were collected and compared with experimental falls performed by middle-aged test subjects. The signals from real-life falls had similar features to those from intentional falls. Real-life forward, sideways and backward falls all showed a pre impact phase and an impact phase that were in keeping with the model that was based on experimental falls. In addition, the fall out of bed had a similar acceleration profile as the experimental falls of the same type. However, there were differences in the parameters that were used for the detection of the fall phases. The beginning of the fall was detected in all of the real-life falls starting from a standing posture, whereas the high pre impact velocity was not. In some real-life falls, multiple impacts suggested protective actions. In conclusion, this study demonstrated similarities between real-life falls of older people and experimental falls of middle-aged subjects. However, some fall characteristics detected from experimental falls were not detectable in acceleration signals from corresponding heterogeneous real-life falls.

  3. Martial arts fall techniques decrease the impact forces at the hip during sideways falling.

    PubMed

    Groen, B E; Weerdesteyn, V; Duysens, J

    2007-01-01

    Falls to the side and those with impact on the hip are risky for hip fractures in the elderly. A previous study has indicated that martial arts (MA) fall techniques can reduce hip impact force, but the underlying mechanism is unknown. Furthermore, the high impact forces at the hand used to break the fall have raised concerns because of the risk for wrist fractures. The purpose of the study was to get insight into the role of hand impact, impact velocity, and trunk orientation in the reduction of hip impact force in MA techniques. Six experienced judokas performed sideways falls from kneeling height using three fall techniques: block with arm technique (control), MA technique with use of the arm to break the fall (MA-a), and MA technique without use of the arm (MA-na). The results showed that the MA-a and MA-na technique reduced the impact force by 27.5% and 30%, respectively. Impact velocity was significantly reduced in the MA falls. Trunk orientation was significantly less vertical in the MA-a falls. No significant differences were found between the MA techniques. It was concluded that the reduction in hip impact force was associated with a lower impact velocity and less vertical trunk orientation. Rolling after impact, which is characteristic for MA falls, is likely to contribute to the reduction of impact forces, as well. Using the arm to break the fall was not essential for the MA technique to reduce hip impact force. These findings provided support for the incorporation of MA fall techniques in fall prevention programs for elderly.

  4. Air Abrasion

    MedlinePlus

    ... delivered directly to your desktop! more... What Is Air Abrasion? Article Chapters What Is Air Abrasion? What Happens? The Pros and Cons Will I Feel Anything? Is Air Abrasion for Everyone? print full article print this ...

  5. Tailored prevention of inpatient falls: development and usability testing of the fall TIPS toolkit.

    PubMed

    Zuyev, Lyubov; Benoit, Angela N; Chang, Frank Y; Dykes, Patricia C

    2011-02-01

    Patient falls and fall-related injuries are serious problems in hospitals. The Fall TIPS application aims to prevent patient falls by translating routine nursing fall risk assessment into a decision support intervention that communicates fall risk status and creates a tailored evidence-based plan of care that is accessible to the care team, patients, and family members. In our design and implementation of the Fall TIPS toolkit, we used the Spiral Software Development Life Cycle model. Three output tools available to be generated from the toolkit are bed poster, plan of care, and patient education handout. A preliminary design of the application was based on initial requirements defined by project leaders and informed by focus groups with end users. Preliminary design partially simulated the paper version of the Morse Fall Scale currently used in hospitals involved in the research study. Strengths and weaknesses of the first prototype were identified by heuristic evaluation. Usability testing was performed at sites where research study is implemented. Suggestions mentioned by end users participating in usability studies were either directly incorporated into the toolkit and output tools, were slightly modified, or will be addressed during training. The next step is implementation of the fall prevention toolkit on the pilot testing units.

  6. Interior cavern conditions and salt fall potential

    SciTech Connect

    Munson, D.E.; Molecke, M.A.; Myers, R.E.

    1998-03-01

    A relatively large number of salt caverns are used for fluid hydrocarbon storage, including an extensive set of facilities in the Gulf Coast salt domes for the Strategic Petroleum Reserve (SPR) Program. Attention is focused on the SPR caverns because of available histories that detail events involving loss and damage of the hanging string casing. The total number of events is limited, making the database statistically sparse. The occurrence of the events is not evenly distributed, with some facilities, and some caverns, more susceptible than others. While not all of these events could be attributed to impacts from salt falls, many did show the evidence of such impacts. As a result, a study has been completed to analyze the potential for salt falls in the SPR storage caverns. In this process, it was also possible to deduce some of the cavern interior conditions. Storage caverns are very large systems in which many factors could possibly play a part in casing damage. In this study, all of the potentially important factors such as salt dome geology, operational details, and material characteristics were considered, with all being logically evaluated and most being determined as secondary in nature. As a result of the study, it appears that a principal factor in determining a propensity for casing damage from salt falls is the creep and fracture characteristics of salt in individual caverns. In addition the fracture depends strongly upon the concentration of impurity particles in the salt. Although direct observation of cavern conditions is not possible, the average impurity concentration and the accumulation of salt fall material can be determined. When this is done, there is a reasonable correlation between the propensity for a cavern to show casing damage events and accumulation of salt fall material. The accumulation volumes of salt fall material can be extremely large, indicating that only a few of the salt falls are large enough to cause impact damage.

  7. Analyzing the problem of falls among older people

    PubMed Central

    Dionyssiotis, Yannis

    2012-01-01

    Falls are a serious problem facing the elderly. The prevention of falls that contribute to disability, mainly in elderly people, is an important issue. Ensuring the greatest possible functionality for elderly people is an important element in the prevention of disability. This paper analyzes the importance of falls, risk factors for falls, and interventions to prevent falls. Recent publications as well as research regarding the prevention and rehabilitation for falls are reviewed. PMID:23055770

  8. OXIDIZED NITROGEN DEPOSITION IN THE EASTERN UNITED STATES

    EPA Science Inventory


    Air quality and selected meteorological parameters have been monitored at rural sites in the United States (US) by EPA's Clean Air Status and Trends Network, (CASTNet) sites. The National Atmospheric Deposition Program (NADP) monitors wet deposition of numerous ions in precip...

  9. Chemical vapor deposition for automatic processing of integrated circuits

    NASA Technical Reports Server (NTRS)

    Kennedy, B. W.

    1980-01-01

    Chemical vapor deposition for automatic processing of integrated circuits including the wafer carrier and loading from a receiving air track into automatic furnaces and unloading on to a sending air track is discussed. Passivation using electron beam deposited quartz is also considered.

  10. Salt deposition at particle contact points

    NASA Astrophysics Data System (ADS)

    Nie, Xiaodong; Evitts, Richard W.; Besant, Robert W.; Kennell, Glyn F.

    2015-09-01

    Caking may occur when granular potash fertilizer with a moisture content greater than 0.25 % (w/w) undergoes drying. Since cake strength is proportional to the mass of crystal deposited per unit volume near contact points (and other factors) the modelling of mass deposition near contact points is important. The Young-Laplace equation for the air-salt-solution interface is used to determine the geometry of a 2-D planar saline film between two cubic potash particles. A 2-D theoretical model is developed and applied for ion diffusion and deposition near the contact point during drying. The numerical predictions of ion diffusion in an initially saturated salt illustrate the transient spatial distribution of new KCl deposits along the solid surfaces near the contact line. These results indicate the average salt deposition commences at the air-liquid-solid intersection, where the liquid film is thinnest, and moves toward the particle contact point with increasing area averaged KCl deposits, causing the formation of crystal deposits and bridges near contact points. It is concluded that the average salt deposit height increases inversely with distance from the contact point and decreases with initial contact angle of the contact region, but the deposition is nearly independent of the evaporation or drying rate near each contact region. Caking strength depends on, among other parameters, the amount of salt deposition near contact points.

  11. Electronic Out-fall Inspection Application - 12007

    SciTech Connect

    Weymouth, A Kent III; Pham, Minh; Messick, Chuck

    2012-07-01

    In early 2009 an exciting opportunity was presented to the Geographic Information Systems (GIS) team at the Savannah River Site (SRS). The SRS maintenance group was directed to maintain all Out-falls on Site, increasing their workload from 75 to 183 out-falls with no additional resources. The existing out-fall inspection system consisted of inspections performed manually and documented via paper trail. The inspections were closed out upon completion of activities and placed in file cabinets with no central location for tracking/trending maintenance activities. A platform for meeting new improvements required for documentation by the Department of Health and Environmental Control (DHEC) out-fall permits was needed to replace this current system that had been in place since the 1980's. This was accomplished by building a geographically aware electronic application that improved reliability of site out-fall maintenance and ensured consistent standards were maintained for environmental excellence and worker efficiency. Inspections are now performed via tablet and uploaded to a central point. Work orders are completed and closed either in the field using tablets (mobile application) or in their offices (via web portal) using PCs. And finally completed work orders are now stored in a central database allowing trending of maintenance activities. (authors)

  12. Stick balancing, falls and Dragon-Kings

    NASA Astrophysics Data System (ADS)

    Cabrera, J. L.; Milton, J. G.

    2012-05-01

    The extent to which the occurrence of falls, the dominant feature of human attempts to balance a stick at their fingertip, can be predicted is examined in the context of the "Dragon-King" hypothesis. For skilled stick balancers, fluctuations in the controlled variable, namely the vertical displacement angle θ, exhibit power law behaviors. When stick balancing is made less stable by either decreasing the length of the stick or by requiring the subject to balance the stick on the surface of a table tennis racket, systematic departures from the power law behaviors are observed in the range of large θ. This observation raises the possibility that the presence of departures from the power law in the large length scale region, possibly Dragon-Kings, may identify situations in which the occurrence of a fall is more imminent. However, whether or not Dragon-Kings are observed, there is a Weibull-type survival function for stick falling. The possibility that increased risk of falling can, at least to some extent, be predicted from fluctuations in the controlled variable before the event occurs has important implications for the development of preventative strategies for the management of phenomena ranging from earthquakes to epileptic seizures to falls in the elderly.

  13. Observations of Precipitation Size and Fall Speed Characteristics within Coexisting Rain and Wet Snow

    NASA Technical Reports Server (NTRS)

    Yuter, Sandra E.; Kingsmill, David E.; Nance, Louisa B.; Loeffler-Mang, Martin

    2006-01-01

    Ground-based measurements of particle size and fall speed distributions using a Particle Size and Velocity (PARSIVEL) disdrometer are compa red among samples obtained in mixed precipitation (rain and wet snow) and rain in the Oregon Cascade Mountains and in dry snow in the Rock y Mountains of Colorado. Coexisting rain and snow particles are distinguished using a classification method based on their size and fall sp eed properties. The bimodal distribution of the particles' joint fall speed-size characteristics at air temperatures from 0.5 to 0 C suggests that wet-snow particles quickly make a transition to rain once mel ting has progressed sufficiently. As air temperatures increase to 1.5 C, the reduction in the number of very large aggregates with a diame ter > 10 mm coincides with the appearance of rain particles larger than 6 mm. In this setting. very large raindrops appear to be the result of aggregates melting with minimal breakup rather than formation by c oalescence. In contrast to dry snow and rain, the fall speed for wet snow has a much weaker correlation between increasing size and increasing fall speed. Wet snow has a larger standard deviation of fall spee d (120%-230% relative to dry snow) for a given particle size. The ave rage fall speed for observed wet-snow particles with a diameter great er than or equal to 2.4 mm is 2 m/s with a standard deviation of 0.8 m/s. The large standard deviation is likely related to the coexistence of particles of similar physical size with different percentages of melting. These results suggest that different particle sizes are not required for aggregation since wet-snow particles of the same size can have different fall speeds. Given the large standard deviation of fa ll speeds in wet snow, the collision efficiency for wet snow is likely larger than that of dry snow. For particle sizes between 1 and 10 mm in diameter within mixed precipitation, rain constituted I % of the particles by volume within the isothermal layer

  14. The stimuli evoking the aerial-righting posture of falling pea aphids.

    PubMed

    Meresman, Yonatan; Ribak, Gal; Weihs, Daniel; Inbar, Moshe

    2014-10-01

    Some wingless insects possess aerial righting reflexes, suggesting that adaptation for controlling body orientation while falling through air could have preceded flight. When threatened by natural enemies, wingless pea aphids (Acyrthosiphon pisum) may drop off their host plant and assume a stereotypic posture that rotates them in midair to land on their feet. The sensory information triggering aphids to assume this posture has so far been unknown. We subjected aphids to a series of tests, isolating the sensory cues experienced during free-fall. Falling aphids assumed the righting posture and landed upright irrespective of whether the experiments were carried out in the light or in complete darkness. Detachment of the tarsi from the substrate triggered the aphids to assume the posture rapidly, but only for a brief period. Rotation (mainly roll and yaw) of the body in air, in the light, caused aphids to assume the posture and remain in it throughout rotation. In contrast, aphids rotated in the dark did not respond. Acceleration associated with falling or airflow over the body per se did not trigger the posture. However, sensing motion relative to air heightened the aphids' responsiveness to rotation in the light. These results suggest that the righting posture of aphids is triggered by a tarsal reflex, but, once the aphid is airborne, vision and a sense of motion relative to air can augment the response. Hence, aerial righting in a wingless insect could have emerged as a basic tarsal response and developed further to include secondary sensory cues typical of falling. PMID:25104755

  15. Falls study: Proprioception, postural stability, and slips.

    PubMed

    Sohn, Jeehoon; Kim, Sukwon

    2015-01-01

    The present study evaluated effects of exercise training on the proprioception sensitivity, postural stability, and the likelihood of slip-induced falls. Eighteen older adults (6 in balance, 6 in weight, and 6 in control groups) participated in this study. Three groups met three times per week over the course of eight weeks. Ankle and knee proprioception sensitivities and postural stability were measured. Slip-induced events were introduced for all participants before and after training. The results indicated that, overall, strength and postural stability were improved only in the training group, although proprioception sensitivity was improved in all groups. Training for older adults resulted in decreased likelihood of slip-induced falls. The study suggested that proprioception can be improved by simply being active, however, the results suggested that training would aid older adults in reducing the likelihood of slip-induced falls.

  16. Fatal falls from bicycles: a case report.

    PubMed

    Venara, A; Mauillon, D; Gaudin, A; Rouge-Maillart, C; Jousset, N

    2013-03-10

    Though rare occurrences, fatal falls from bicycles are generally linked to the absence of a protective helmet and/or a collision with another vehicle. The case presented here is exceptional due to its circumstances and the consequences of the accident: a fall with no obstacle at a low speed that brought about multiple traumas and the death of a cyclist wearing a protective helmet. Comparing this against a review of cyclist accidentology literature, this case is unique. The increased use of autopsy in terms of forensic accidentology is to be encouraged so as not to misunderstand the possibility of such lesion-based consequences following a simple fall from a bicycle. PMID:23312586

  17. REDUCTION OF THE MOMENTUM OF FALLING BODIES

    DOEpatents

    Kendall, J.W.; Morrison, I.H.

    1954-09-21

    A means for catching free falling bodies that may be damaged upon impact is given. Several layers of floating gas-filled rubber balls are contained within a partially compartmented tank of liquid. The compartment extends from beneath the surface of the liquid to that height necessary to contain the desired number of layers of the balls. The balls and the liquid itself break the force of the fall by absorbing the kinetic energy of falling body. The body may then be retrieved from the floor of the tank by a rake that extends from outside of the tank through the free surface area and underneath the compartment wall. This arrangement is particularly useful in collecting irradiated atomic fuel rods that are discharged from a reactor at considerable height without damaging the thin aluminum jacket of the rods.

  18. Elderly fall detection using SIFT hybrid features

    NASA Astrophysics Data System (ADS)

    Wang, Xiaoxiao; Gao, Chao; Guo, Yongcai

    2015-10-01

    With the tendency of aging society, countries all over the world are dealing with the demographic change. Fall had been proven to be of the highest fatality rate among the elderly. To realize the elderly fall detection, the proposed algorithm used the hybrid feature. Based on the rate of centroid change, the algorithm adopted VEI to offer the posture feature, this combined motion feature with posture feature. The algorithm also took advantage of SIFT descriptor of VEI(V-SIFT) to show more details of behaviors with occlusion. An improved motion detection method was proposed to improve the accuracy of front-view motion detection. The experimental results on CASIA database and self-built database showed that the proposed approach has high efficiency and strong robustness which effectively improved the accuracy of fall detection.

  19. Falls study: Proprioception, postural stability, and slips.

    PubMed

    Sohn, Jeehoon; Kim, Sukwon

    2015-01-01

    The present study evaluated effects of exercise training on the proprioception sensitivity, postural stability, and the likelihood of slip-induced falls. Eighteen older adults (6 in balance, 6 in weight, and 6 in control groups) participated in this study. Three groups met three times per week over the course of eight weeks. Ankle and knee proprioception sensitivities and postural stability were measured. Slip-induced events were introduced for all participants before and after training. The results indicated that, overall, strength and postural stability were improved only in the training group, although proprioception sensitivity was improved in all groups. Training for older adults resulted in decreased likelihood of slip-induced falls. The study suggested that proprioception can be improved by simply being active, however, the results suggested that training would aid older adults in reducing the likelihood of slip-induced falls. PMID:26406065

  20. Electrostatic demonstration of free-fall weightlessness

    NASA Astrophysics Data System (ADS)

    Balukovic, Jasmina; Slisko, Josip; Corona Cruz, Adrian

    2015-05-01

    The phenomena of free-fall weightlessness have been demonstrated to students for many years in a number of different ways. The essential basis of all these demonstrations is the fact that in free-falling, gravitationally accelerated systems, the weight force and weight-related forces (for example, friction and hydrostatic forces) disappear. In this article, an original electrostatic demonstration of weightlessness is presented. A charged balloon fixed at the opening of a plastic container cannot lift a light styrofoam sphere sitting on the bottom when the container is at rest. However, while the system is in free-fall, the sphere becomes weightless and the charged balloon is able to lift it electrostatically.

  1. Evaluation of a regional air-quality model with bidirectional NH3 exchange coupled to an agroecosystem model

    NASA Astrophysics Data System (ADS)

    Bash, J. O.; Cooter, E. J.; Dennis, R. L.; Walker, J. T.; Pleim, J. E.

    2013-03-01

    Atmospheric ammonia (NH3) is the primary atmospheric base and an important precursor for inorganic particulate matter and when deposited NH3 contributes to surface water eutrophication, soil acidification and decline in species biodiversity. Flux measurements indicate that the air-surface exchange of NH3 is bidirectional. However, the effects of bidirectional exchange, soil biogeochemistry and human activity are not parameterized in air quality models. The US Environmental Protection Agency's (EPA) Community Multiscale Air-Quality (CMAQ) model with bidirectional NH3 exchange has been coupled with the United States Department of Agriculture's (USDA) Environmental Policy Integrated Climate (EPIC) agroecosystem model. The coupled CMAQ-EPIC model relies on EPIC fertilization timing, rate and composition while CMAQ models the soil ammonium (NH4+) pool by conserving the ammonium mass due to fertilization, evasion, deposition, and nitrification processes. This mechanistically coupled modeling system reduced the biases and error in NHx (NH3 + NH4+) wet deposition and in ambient aerosol concentrations in an annual 2002 Continental US (CONUS) domain simulation when compared to a 2002 annual simulation of CMAQ without bidirectional exchange. Fertilizer emissions estimated in CMAQ 5.0 with bidirectional exchange exhibits markedly different seasonal dynamics than the US EPA's National Emissions Inventory (NEI), with lower emissions in the spring and fall and higher emissions in July.

  2. Sacramento City College Assessment Center Research Report: Assessment Procedures, Fall 1983 - Fall 1984.

    ERIC Educational Resources Information Center

    Haase, M.; Caffrey, Patrick

    Studies and analyses conducted by the Assessment Center at Sacramento City College (SCC) between fall 1983 and fall 1984 provided the data on SCC's students and services which are presented in this report. Following an overview of the significant findings of the year's research efforts, part I sets forth the purpose of the report and part II…

  3. Mohawk Valley Community College (MVCC) Trend Data Book. Analysis Period: Fall 1993-Fall 1997.

    ERIC Educational Resources Information Center

    Russo, Samuel L., Jr.

    This trend data book from Mohawk Valley Community College (MVCC) in New York contains six statistical reports for the following areas: Enrollment, Admissions, Academic Programs, Graduate/Placement, Administrative/Financial, and Personnel. The analysis period covered is fall 1993 through fall 1997. The Enrollment section provides student headcounts…

  4. Seniors Falls Investigative Methodology (SFIM): A Systems Approach to the Study of Falls in Seniors

    ERIC Educational Resources Information Center

    Zecevic, Aleksandra A.; Salmoni, Alan W.; Lewko, John H.; Vandervoort, Anthony A.

    2007-01-01

    An in-depth understanding of human factors and human error is lacking in current research on seniors' falls. Additional knowledge is needed to understand why seniors are falling. The purpose of this article is to describe the adapting of the Integrated Safety Investigation Methodology (ISIM) (used for investigating transportation and industrial…

  5. Results of the Colorado Student Assessment Program, Fall 1988 and Fall 1991.

    ERIC Educational Resources Information Center

    Colorado State Dept. of Education, Denver.

    Colorado conducts an assessment program to provide a statewide profile of student achievement. Results for fall 1988 and fall 1991 are presented in a series of tables. A standardized, nationally norm-referenced achievement test, the Iowa Tests of Basic Skills, was administered in 1988 to students in grades 4, 7, and 10, and again to the same…

  6. Thou shalt not fall! Decreasing falls in the postoperative orthopedic patient with a femoral nerve block.

    PubMed

    Foisy, Kimberly

    2013-01-01

    A Transforming Care at the Bedside model was used to decrease falls in the femoral nerve block (FNB) patient population on a 32-bed orthopedic/neurologic unit in a community hospital setting. A multifaceted, strategic practice and educational bundle was implemented, resulting in a 75% decrease in falls among patients with FNB.

  7. Some characteristics of fall migration of female woodcock

    USGS Publications Warehouse

    Coon, R.A.; Caldwell, P.D.; Storm, G.L.

    1976-01-01

    Nine female woodcock (Philohela minor) were radio-tagged in central Pennsylvania before fall migration to monitor premigratory and migratory movements. Within 15 days of departure, 5 of the birds moved 0.8 to 8.0 km from their normally used area, but the remaining 4 did not move. In 1973 five marked woodcock began migration between 30 November and 8 December. In 1974, four birds departed between 18 and 29 November. Departures coincided with high pressure centers approaching from the north and west or low pressure centers retreating to the north and east, or both. Eight of the 9 woodcock departed 2.5 or more hours after sunset and at least 7 left before midnight. Two hatching-year birds were tracked for up to 201 km SSW of the study area during 2 nights. Their air speeds (mean + SD) were 36 + 2 and 45 + 3 km/h.

  8. Radar and Scattering Parameters Through Falling Hydrometeors with Axisymmetric Shapes

    NASA Astrophysics Data System (ADS)

    Battaglia, Alessandro; Prodi, Franco; Sturniolo, Orazio

    2001-06-01

    Falling raindrops and other hydrometeors have, in general, nonspherical shapes and mean canting angles that are due to aerodynamic and gravitational forces. We use the T matrix and the quantum theory of angular momentum to compute extinction matrices, scattering and absorption cross sections, backscattering matrices, and, from these quantities, radar parameters. A monodisperse population of rain with axially symmetric distribution over orientations where the axis of symmetry is the local direction of air flow about the raindrops is considered. Oblate spheroids with axial ratios that depend on size and appropriate series of Chebyshev polynomials were assumed for definition of the shapes of raindrops. Computations were performed at common microwave frequencies for several temperatures, incidence angles, and degrees of particle wobble about a preferred orientation. Results reveal the importance of the role of orientation distribution and particle size and the shape of radar parameters in these computations for a region of moderate-sized raindrops.

  9. Two Empirical Models for Land-falling Hurricane Gust Factors

    NASA Technical Reports Server (NTRS)

    Merceret, Franics J.

    2008-01-01

    Gaussian and lognormal models for gust factors as a function of height and mean windspeed in land-falling hurricanes are presented. The models were empirically derived using data from 2004 hurricanes Frances and Jeanne and independently verified using data from 2005 hurricane Wilma. The data were collected from three wind towers at Kennedy Space Center and Cape Canaveral Air Force Station with instrumentation at multiple levels from 12 to 500 feet above ground level. An additional 200-foot tower was available for the verification. Mean wind speeds from 15 to 60 knots were included in the data. The models provide formulas for the mean and standard deviation of the gust factor given the mean windspeed and height above ground. These statistics may then be used to assess the probability of exceeding a specified peak wind threshold of operational significance given a specified mean wind speed.

  10. Free fall and harmonic oscillations: analyzing trampoline jumps

    NASA Astrophysics Data System (ADS)

    Pendrill, Ann-Marie; Eager, David

    2015-01-01

    Trampolines can be found in many gardens and also in some playgrounds. They offer an easily accessible vertical motion that includes free fall. In this work, the motion on a trampoline is modelled by assuming a linear relation between force and deflection, giving harmonic oscillations for small amplitudes. An expression for the cycle-time is obtained in terms of maximum normalized force from the trampoline and the harmonic frequency. A simple expression is obtained for the ratio between air-time and harmonic period, and the maximum g-factor. The results are compared to experimental results, including accelerometer data showing 7g during bounces on a small trampoline in an amusement park play area. Similar results are obtained on a larger garden trampoline, and even larger accelerations have been measured for gymnastic trampolines.

  11. Public events at Fall Meeting 2012

    NASA Astrophysics Data System (ADS)

    Holm Adamec, Bethany

    2012-11-01

    Three much-anticipated events at Fall Meeting are AGU's family science programs, which take place the Sunday before Fall Meeting begins. Beginning at noon on 2 December, the public lecture will be given by Michael Meyer, John Grotzinger, and Rebecca Williams. These three NASA scientists are working with the rover Curiosity, which is currently exploring Mars. They will engage the public in a discussion of Mars exploration and the latest activities of the most sophisticated explorer ever sent to another planet. The panelists will discuss the hopes and excitement of exploring Mars through a robot's eyes, nose, taste, and touch.

  12. The particles in town air

    PubMed Central

    Ellison, J. McK.

    1965-01-01

    Particles constitute an important part of air pollution, and their behaviour when suspended in air is very different from that of gas molecules: in particular, the mechanisms by which they become deposited on surfaces are different, and consequently the methods normally used for removing particles from the air, either for sampling or for cleaning it, rely mainly on mechanisms that do not enter into the behaviour of gas molecules. These mechanisms are described, and the ways in which they affect the problems of air pollution and its measurement are discussed. ImagesFIG. 8 PMID:14315713

  13. Coastal lows and sulfur air pollution in Central Chile

    NASA Astrophysics Data System (ADS)

    Gallardo, L.; Olivares, G.; Langner, J.; Aarhus, B.

    Air pollutants in Santiago (33.5°S, 70.8°W, 500 m a.s.l.), a city with 5 million inhabitants, located in a basin in Central Chile surrounded by the high Andes, frequently exceed air quality standards. This affects human health and it stresses vegetation. The most extreme winter and fall pollution events occur when the subsident regime of the Pacific high is further enhanced by coastal lows (CLs), which bring down the base of the subsidence inversion. Under these conditions, the air quality worsens significantly giving rise to acute air pollution episodes. We assess the ability of a regional transport/chemistry/deposition model (MATCH) coupled to a meteorological model (High Resolution Limited Area Model—HIRLAM) to simulate the evolution of oxidized sulfur (SO x) in connection with intensive CLs. We focus on SO x since it is an environmental issue of concern, and the emissions and concentrations of SO x have been regularly monitored making it easier to bracket model outputs for SO x than for other pollutants. Furthermore, the SO x emissions in the area are very large, i.e., about 0.4% of the global anthropogenic sources. Comparisons with observations indicate that the combination of HIRLAM and MATCH is a suitable tool for describing the regional patterns of dispersion associated with CLs. However, the low number and the limited geographical coverage of reliable air quality data preclude a complete evaluation of the model. Nevertheless, we show evidence of an enhanced contribution of the largest copper smelter in the area, i.e., Caletones, to the burden of SO x in the Santiago basin, especially in the form of sulfate associated to fine particles (diameters <2.5 μm), during CLs. Further, we speculate that the Caletones plume may trigger or promote secondary aerosol formation during CLs in the Santiago basin.

  14. Phenological controls on inter-annual variability in ozone dry deposition velocity

    NASA Astrophysics Data System (ADS)

    Clifton, Olivia; Fiore, Arlene; Munger, J. William; Shevliakova, Elena; Horowitz, Larry; Malyshev, Sergey; Griffin, Kevin

    2016-04-01

    Our understanding of ozone removal by northern mid-latitude temperate deciduous forests is largely based on short-term observational studies, and thus year-to-year variations of this sink have received little attention. The specific pathways for ozone dry deposition include stomatal uptake and other non-stomatal processes that are poorly understood. Given the importance of ozone dry deposition to model accurately the tropospheric ozone budget and regional air quality, an improved mechanistic understanding of this ozone sink is needed. We investigate here the physical and biological controls on inter-annual variations in seasonal and diurnal cycles of ozone dry deposition velocity using nine years of hourly observations of eddy covariance ozone flux and concentration measurements at Harvard Forest, a northern mid-latitude temperate deciduous forest. We also use coincident eddy covariance water vapor flux and sensible heat flux and other micrometeorological measurements to infer stomatal conductance in order to separate the impacts of stomatal versus non-stomatal pathways on ozone deposition. There is a difference of approximately a factor of two between minimum and maximum monthly daytime mean ozone dry deposition velocities at Harvard Forest. The highest summertime mean ozone dry deposition velocities occur during 1998 and 1999 (0.72 cm/s), and similar seasonal and diurnal cycles occur in both years. The similar dry deposition velocities during these two years, however, may reflect compensation between different processes as mean daytime summertime stomatal conductance during 1998 is roughly 1.5 times higher than for 1999, suggesting large year-to-year variations in non-stomatal as well as stomatal uptake of ozone. We partition the onset and decline of the growing season each year into different periods using spring and fall phenology observations at Harvard Forest. Combining the dry deposition velocities across years during each phenological period, we find that

  15. Perchlorate in dust fall and indoor dust in Malta: An effect of fireworks.

    PubMed

    Vella, Alfred J; Chircop, Cynthia; Micallef, Tamara; Pace, Colette

    2015-07-15

    We report on the presence of perchlorate in the settleable dust of Malta, a small central Mediterranean island. Both dust fall collected directly as it precipitated from atmosphere over a period of one month and deposited indoor dust from domestic residences were studied. Perchlorate was determined by ion chromatography of water extracts of the collected dusts. Dust fall was collected from 43 towns during 2011 to 2013 and indoor dust was sampled from homes in the same localities. Perchlorate was detected in 108 of 153 samples of dust fall (71%) and in 28 of 37 indoor dust samples (76%). Detectable perchlorate in dust fall ranged from 0.52μgg(-1) to 561μgg(-1) with a median value of 6.2μgg(-1); in indoor dust, levels were from 0.79μgg(-1) to 53μgg(-1) with a median value of 7.8μgg(-1), the highest recorded anywhere to date. Statistical analysis suggested that there was no significant difference in perchlorate content of indoor dust and dust fall. Perchlorate levels in dust fall escalate during the summer in response to numerous religious feasts celebrated with fireworks and perchlorate persists at low μgg(-1) concentrations for several months beyond the summer festive period. In Malta, perchlorate derives exclusively from KClO4, imported for fireworks manufacture. Its residue in dust presents an exposure risk to the population, especially via ingestion by hand to mouth transfer. Our results suggest that wherever intensive burning of fireworks takes place, the environmental impact may be much longer lived than realised, mainly due to re-suspension and deposition of contaminated settled dust in the urban environment.

  16. Perchlorate in dust fall and indoor dust in Malta: An effect of fireworks.

    PubMed

    Vella, Alfred J; Chircop, Cynthia; Micallef, Tamara; Pace, Colette

    2015-07-15

    We report on the presence of perchlorate in the settleable dust of Malta, a small central Mediterranean island. Both dust fall collected directly as it precipitated from atmosphere over a period of one month and deposited indoor dust from domestic residences were studied. Perchlorate was determined by ion chromatography of water extracts of the collected dusts. Dust fall was collected from 43 towns during 2011 to 2013 and indoor dust was sampled from homes in the same localities. Perchlorate was detected in 108 of 153 samples of dust fall (71%) and in 28 of 37 indoor dust samples (76%). Detectable perchlorate in dust fall ranged from 0.52μgg(-1) to 561μgg(-1) with a median value of 6.2μgg(-1); in indoor dust, levels were from 0.79μgg(-1) to 53μgg(-1) with a median value of 7.8μgg(-1), the highest recorded anywhere to date. Statistical analysis suggested that there was no significant difference in perchlorate content of indoor dust and dust fall. Perchlorate levels in dust fall escalate during the summer in response to numerous religious feasts celebrated with fireworks and perchlorate persists at low μgg(-1) concentrations for several months beyond the summer festive period. In Malta, perchlorate derives exclusively from KClO4, imported for fireworks manufacture. Its residue in dust presents an exposure risk to the population, especially via ingestion by hand to mouth transfer. Our results suggest that wherever intensive burning of fireworks takes place, the environmental impact may be much longer lived than realised, mainly due to re-suspension and deposition of contaminated settled dust in the urban environment. PMID:25828411

  17. Photocopy of drawing, "Sluiceway at Combined Locks, Glens Falls Feeder" ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Photocopy of drawing, "Sluiceway at Combined Locks, Glens Falls Feeder" (from Champlain canal structure book) 6-45, New York State Archives and Manuscripts, Albany, New York), c. 1858 - Glens Falls Feeder, Sluice, Along south side of Glens Falls Feeder between locks 10 & 20, Hudson Falls, Washington County, NY

  18. 113. ROCK CREEK SIPHON LOW LINE CANAL, TWIN FALLS COUNTY, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    113. ROCK CREEK SIPHON LOW LINE CANAL, TWIN FALLS COUNTY, SOUTH OF KIMBERLY IDAHO; CLOSE-UP OF INLET SIDE OF SIPHON, NORTHWEST VIEW. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

  19. 126. COTTONWOOD CREEK SIPHON, TWIN FALLS COUNTY, SOUTH OF KIMBERLY, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    126. COTTONWOOD CREEK SIPHON, TWIN FALLS COUNTY, SOUTH OF KIMBERLY, IDAHO; CLOSE-UP OF OUTLET SIDE OF SIPHON, SOUTH VIEW. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

  20. 111. ROCK CREEK SIPHON LOW LINE CANAL, TWIN FALLS COUNTY, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    111. ROCK CREEK SIPHON LOW LINE CANAL, TWIN FALLS COUNTY, SOUTH OF KIMBERLY IDAHO; OVERALL VIEW OF SIPHON, EAST VIEW. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

  1. 129. COTTONWOOD CREEK SIPHON, TWIN FALLS COUNTY, SOUTH OF KIMBERLY, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    129. COTTONWOOD CREEK SIPHON, TWIN FALLS COUNTY, SOUTH OF KIMBERLY, IDAHO; OUTLET SIDE OF SIPHON UNDER CANAL. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

  2. 115. ROCK CREEK SIPHON LOW LINE CANAL, TWIN FALLS COUNTY, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    115. ROCK CREEK SIPHON LOW LINE CANAL, TWIN FALLS COUNTY, SOUTH OF KIMBERLY IDAHO; WEST VIEW OF SIPHON CROSSING ROCK CREEK. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

  3. A Profile of the Fall 1979 Freshmen at CUNY.

    ERIC Educational Resources Information Center

    Kramer, Rena

    A profile of the fall 1979 first-time freshmen at the City University of New York (CUNY) is presented and comparisons are made with the fall 1975 and 1976 classes. In fall 1976, tuition was imposed for the first time and new admissions criteria were set. In comparison to fall 1976 enrollments, the number of first-time freshmen enrollment at CUNY…

  4. 197. Photocopy of drawing, Twin Falls, Canal Company, date unknown. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    197. Photocopy of drawing, Twin Falls, Canal Company, date unknown. GATE STEMS AND LIFTING DEVICES, NO COUNTY; BLUEPRINT SKETCHES. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

  5. A Radon Progeny Deposition Model

    SciTech Connect

    Guiseppe, V. E.; Elliott, S. R.; Hime, A.; Rielage, K.; Westerdale, S.

    2011-04-27

    The next generation low-background detectors operating underground aim for unprecedented low levels of radioactive backgrounds. Although the radioactive decays of airborne radon (particularly {sup 222}Rn) and its subsequent progeny present in an experiment are potential backgrounds, also problematic is the deposition of radon progeny on detector materials. Exposure to radon at any stage of assembly of an experiment can result in surface contamination by progeny supported by the long half life (22 y) of {sup 210}Pb on sensitive locations of a detector. An understanding of the potential surface contamination from deposition will enable requirements of radon-reduced air and clean room environments for the assembly of low background experiments. It is known that there are a number of environmental factors that govern the deposition of progeny onto surfaces. However, existing models have not explored the impact of some environmental factors important for low background experiments. A test stand has been constructed to deposit radon progeny on various surfaces under a controlled environment in order to develop a deposition model. Results from this test stand and the resulting deposition model are presented.

  6. A Radon Progeny Deposition Model

    NASA Astrophysics Data System (ADS)

    Guiseppe, V. E.; Elliott, S. R.; Hime, A.; Rielage, K.; Westerdale, S.

    2011-04-01

    The next generation low-background detectors operating underground aim for unprecedented low levels of radioactive backgrounds. Although the radioactive decays of airborne radon (particularly 222Rn) and its subsequent progeny present in an experiment are potential backgrounds, also problematic is the deposition of radon progeny on detector materials. Exposure to radon at any stage of assembly of an experiment can result in surface contamination by progeny supported by the long half life (22 y) of 210Pb on sensitive locations of a detector. An understanding of the potential surface contamination from deposition will enable requirements of radon-reduced air and clean room environments for the assembly of low background experiments. It is known that there are a number of environmental factors that govern the deposition of progeny onto surfaces. However, existing models have not explored the impact of some environmental factors important for low background experiments. A test stand has been constructed to deposit radon progeny on various surfaces under a controlled environment in order to develop a deposition model. Results from this test stand and the resulting deposition model are presented.

  7. A radon progeny deposition model

    SciTech Connect

    Rielage, Keith; Elliott, Steven R; Hime, Andrew; Guiseppe, Vincente E; Westerdale, S.

    2010-12-01

    The next generation low-background detectors operating underground aim for unprecedented low levels of radioactive backgrounds. Although the radioactive decays of airborne radon (particularly {sup 222}Rn) and its subsequent progeny present in an experiment are potential backgrounds, also problematic is the deposition of radon progeny on detector materials. Exposure to radon at any stage of assembly of an experiment can result in surface contamination by progeny supported by the long half life (22 y) of {sup 210}Pb on sensitive locations of a detector. An understanding of the potential surface contamination from deposition will enable requirements of radon-reduced air and clean room environments for the assembly of low background experiments. It is known that there are a number of environmental factors that govern the deposition of progeny onto surfaces. However, existing models have not explored the impact of some environmental factors important for low background experiments. A test stand has been constructed to deposit radon progeny on various surfaces under a controlled environment in order to develop a deposition model. Results from this test stand and the resulting deposition model are presented.

  8. 29 CFR 1926.760 - Fall protection.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Steel Erection § 1926.760 Fall protection. (a... a steel erection activity who is on a walking/working surface with an unprotected side or edge more... (CDZ). A controlled decking zone may be established in that area of the structure over 15 and up to...

  9. 29 CFR 1926.760 - Fall protection.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Steel Erection § 1926.760 Fall protection. (a... a steel erection activity who is on a walking/working surface with an unprotected side or edge more... (CDZ). A controlled decking zone may be established in that area of the structure over 15 and up to...

  10. Harvesting strawberries in fall and early spring

    Technology Transfer Automated Retrieval System (TEKTRAN)

    New management strategies are needed to produce strawberry planting materials that will fruit in the off-season in the mid-Atlantic coast region. Also, a better understanding of mechanisms that control flowering in strawberries is needed to improve fall flowering in short-day type cultivars. When ...

  11. Riemann pendulum in free fall systems

    NASA Astrophysics Data System (ADS)

    Fargion, Daniele

    2016-07-01

    The possible detection in space and in different free fall system of the tidal effects via a Riemann pendulum rate, is considered. The possibility to perform such an experiment for educational purpouse by a Moire' or Holographic double exposure detection is described. The International Space Station may obtain high quality test of 3D Riemann pendulum effects.

  12. Grade Distribution. Community Colleges, Fall 1978.

    ERIC Educational Resources Information Center

    Hawaii Univ., Honolulu. Community Coll. System.

    Data on the grade point ratios (GPR's) and the distribution of grades earned were gathered and analyzed for all students enrolled in credit courses at the seven Hawaii community colleges during Fall 1978. These data indicate that the average assigned grade was 2.7, and that the credits-earned rate was 71%. As in previous semesters, the…

  13. Kentucky College and University Enrollments, Fall 1987.

    ERIC Educational Resources Information Center

    Kentucky Council on Public Higher Education, Frankfort.

    Statistical information on Kentucky college and university enrollments for the fall of 1987 are provided, including listings of the membership of the Commonwealth of Kentucky Council on Higher Education, and the presidents of Kentucky's senior colleges and universities, junior and community colleges, seminaries, and business colleges. The 41…

  14. West Tennessee ACEI 2006 Fall Conference

    ERIC Educational Resources Information Center

    Clifford, Anna; Hailey, Beth

    2007-01-01

    This article presents the West Tennessee ACEI 2006 Fall Conference held at Union University in Jackson, Tennessee on October 14, 2006. The conference theme, Turning the Pages: A Focus on Children's Literature, was emphasized throughout the day. During the conference, the early childhood classroom teachers, preservice teachers, and administrators…

  15. Ethnic Student Survey--Fall 1995.

    ERIC Educational Resources Information Center

    Moraine Valley Community College., Palos Hills, IL. Office of Institutional Research.

    In fall 1995, Illinois' Moraine Valley Community College (MVCC) conducted a survey of a random sample of 1,447 current students to gather information on their attitudes and goals and to compare responses for Asian, Black, Hispanic, and White students. Completed surveys were received from 433 students, including 53 Asians, 73 Blacks, 127 Hispanics,…

  16. Cohort Analysis, Fall 1993 New Students.

    ERIC Educational Resources Information Center

    Moraine Valley Community College., Palos Hills, IL. Office of Institutional Research.

    In October 1996, Illinois' Moraine Valley Community College (MVCC) conducted a longitudinal study of the characteristics of and outcomes experienced by students who entered the college for the first time in fall 1993, gathering data on retention rates, average attempted and earned cumulative hours, and graduation rates over 3 years. Of the 3,146…

  17. TAP into Learning, Fall-Winter 2000.

    ERIC Educational Resources Information Center

    Burns, Mary; Dimock, Vicki; Martinez, Danny

    2000-01-01

    This document consists of the final three issues of "TAP into Learning" (Technology Assistance Program). The double fall issue focuses on knowledge construction and on using multimedia applications in the classroom. Contents include: "Knowledge Under Construction"; "Hegel and the Dialectic"; "Implications for Teaching and Learning"; "How Can…

  18. Artists Paint ... Fall: Grades K-1

    ERIC Educational Resources Information Center

    Herberholz, Barbara

    2012-01-01

    Artists often paint the different seasonal activities people engage in and the way the world looks as changes take place. The weather for each of the four seasons is different. Farmers plant crops and gardens in the spring and harvest their crops in the fall, just like "The Harvesters" by Pieter Bruegel the Elder. To begin, children will observe…

  19. Freshman Profile, Entering Class: Fall 1974.

    ERIC Educational Resources Information Center

    Martin, Peter B.

    In fall 1974, Hostos Community College (HCC) participated in the national survey of college freshmen which is conducted annually by the Cooperative Institutional Research Program (CIRP) of the American Council on Education, and UCLA. The population served by Hostos Community College is, for the most part, comprised of economically disadvantaged,…

  20. Occupational Programs Student Survey, Fall 2002. Report.

    ERIC Educational Resources Information Center

    Meuschke, Daylene M.; Gribbons, Barry C.

    Each semester, the College of the Canyons (California) surveys all students enrolled in occupational courses. This information has three primary purposes: (1) the survey results are used in determining funding through the Vocational and Technical Education Act (VTEA); (2) beginning in fall 2000, the College expanded the survey to include students'…

  1. Community College Users' Report, Fall 1975.

    ERIC Educational Resources Information Center

    Zimmer, A. L., Ed.

    This report was compiled from information supplied by instructors participating in the National Science Foundation's community college field test of PLATO IV--a computer-based system developed at the University of Illinois--during the fall semester of 1975. Represented here are the responses of instructors at five Illinois community colleges to…

  2. Seneca Falls: A Women's Demonstration for Peace.

    ERIC Educational Resources Information Center

    Khan, Billie

    1984-01-01

    A reporter gives her personal impressions of the Seneca Falls Women's Encampment for a Future of Peace and Justice and the march by members of the encampment to the Seneca Army Depot. Confrontations between the demonstrators and conservative counterdemonstrators and the army response are also covered. (IS)

  3. Kentucky College and University Enrollments. Fall 1977.

    ERIC Educational Resources Information Center

    Kentucky Center for Education Statistics, Frankfort.

    Fall 1977 enrollment data from the Kentucky state-supported and independent colleges and universities, seminaries, proprietary business colleges and Eagle University are presented. Total enrollment in the state and independent colleges and universities was 126,162. Of this total, 108,546 students were enrolled in the state universities and…

  4. OATYC Journal, Fall 1990-Spring 1991.

    ERIC Educational Resources Information Center

    Fullen, Jim, Ed.

    1991-01-01

    Published by the Ohio Association of Two-Year Colleges, the "OATYC Journal" is designed to provide a medium for sharing concepts, methods, and findings relevant to the classroom, and an open forum for the discussion and review of problems. This 16th volume of the journal, consisting of the fall 1990 and spring 1991 issues, contains the following…

  5. Early Childhood: Fall Harvest and Science.

    ERIC Educational Resources Information Center

    Science and Children, 1982

    1982-01-01

    Provides instructional strategies for using fall fruits/vegetables in science lessons, including activities related to melons, pumpkins, grapes, pears, squash, and yams. Suggests extending the activities over a month or more to allow children time to explore and investigate. (JN)

  6. Analysis of Fall 1996 Course Grades.

    ERIC Educational Resources Information Center

    McGregor, Ellen N.; Reece, Dee; Garner, Doris

    This report provides data on withdrawal and success rates and grades earned in fall 1996 at the five campuses of Pima Community College (PCC) in Arizona. Following a literature review on national course grades, descriptions are provided of the following: (1) grades and withdrawals for 1981, 1986, 1991, and 1996, indicating that the number of A…

  7. Analysis of Fall 1995 Course Grades.

    ERIC Educational Resources Information Center

    Pima Community Coll., Tucson, AZ. Office of Institutional Research.

    This report provides data on withdrawal and success rates and grades earned in fall 1995 at the five campuses of Pima Community College (PCC) in Arizona. Following a literature review on national course grades, descriptions are provided of the following: (1) grades and withdrawals for 1980, 1985, 1990, and 1995, indicating that the number of A…

  8. Students Enrolled for Advanced Degrees, Fall 1972.

    ERIC Educational Resources Information Center

    Baker, Curtis O.; Wells, Agnes Q.

    The seventh annual Higher Education General Information Survey (HEGIS) acquired these data in 1972-73 for students enrolled for advanced degrees in fall 1972. Included in this report are summary enrollment tables by level of study, attendance status, sex of student, discipline specialty, state or other area, and institutional control and level.…

  9. Academic Crossover Study: Community Colleges, Fall 1981.

    ERIC Educational Resources Information Center

    Hawaii Univ., Honolulu. Office of Institutional Research and Analysis.

    In fall 1981, a study was conducted in Hawaii's community colleges to determine the course-taking patterns of different groups of student majors (e.g., the proportion of the liberal arts major's academic load that is taken in the humanities, natural sciences, etc.), and the client-serving patterns of different subject disciplines (e.g., the…

  10. NOVA[R] Fall 2001 Teacher's Guide.

    ERIC Educational Resources Information Center

    WGBH-TV, Boston, MA.

    This teacher guide includes activity information for the program NOVA, Fall 2001. Background for each activity is provided along with its correlation to the national science standards. Activities include: (1) "Search for a Safe Cigarette"; (2) "18 Ways To Make a Baby"; (3) "Secrets of Mind"; (4) "Neanderthals on Trial"; (5) "Life's Greatest…

  11. Fall Colors, Temperature, and Day Length

    ERIC Educational Resources Information Center

    Burton, Stephen; Miller, Heather; Roossinck, Carrie

    2007-01-01

    Along with the bright hues of orange, red, and yellow, the season of fall represents significant changes, such as day length and temperature. These changes provide excellent opportunities for students to use science process skills to examine how abiotic factors such as weather and temperature impact organisms. In this article, the authors describe…

  12. Anode Fall Formation in a Hall Thruster

    SciTech Connect

    Leonid A. Dorf; Yevgeny F. Raitses; Artem N. Smirnov; Nathaniel J. Fisch

    2004-06-29

    As was reported in our previous work, accurate, nondisturbing near-anode measurements of the plasma density, electron temperature, and plasma potential performed with biased and emissive probes allowed the first experimental identification of both electron-repelling (negative anode fall) and electron-attracting (positive anode fall) anode sheaths in Hall thrusters. An interesting new phenomenon revealed by the probe measurements is that the anode fall changes from positive to negative upon removal of the dielectric coating, which appears on the anode surface during the course of Hall thruster operation. As reported in the present work, energy dispersion spectroscopy analysis of the chemical composition of the anode dielectric coating indicates that the coating layer consists essentially of an oxide of the anode material (stainless steel). However, it is still unclear how oxygen gets into the thruster channel. Most importantly, possible mechanisms of anode fall formation in a Hall thruster with a clean and a coated anodes are analyzed in this work; practical implication of understanding the general structure of the electron-attracting anode sheath in the case of a coated anode is also discussed.

  13. Does Fall History Influence Residential Adjustments?

    ERIC Educational Resources Information Center

    Leland, Natalie; Porell, Frank; Murphy, Susan L.

    2011-01-01

    Purpose of the study: To determine whether reported falls at baseline are associated with an older adult's decision to make a residential adjustment (RA) and the type of adjustment made in the subsequent 2 years. Design and Methods: Observations (n = 25,036) were from the Health and Retirement Study, a nationally representative sample of…

  14. Community College Humanities Review, Fall 1998.

    ERIC Educational Resources Information Center

    Hult, Susan, Ed.; Wilson, Ned M., Ed.

    1998-01-01

    The "Community College Humanities Review" is a forum for scholarly work focusing on research, curriculum change, and developments within the humanities disciplines. The fall 1998 issue offers the following articles: (1) "Feminist Currents and Confluence in Southern and Latin America, Women's Narrative: Gertrudis Gomez de Avellaneda y Arteaga and…

  15. Integrating the Curriculum: Faux Fall Repousse

    ERIC Educational Resources Information Center

    Kernan, Christine

    2012-01-01

    When introducing a new unit, art teachers know that sometimes a little "bling" can really grab students' attention. The author received "ooohs" and "aaahs" from her fourth-graders when they learned they would be creating "Faux Fall Repousse." The dazzling shine of the aluminum foil and the beautiful array of autumnal colors were impossible for…

  16. Persistence Rates in Day Classes: Fall, 1978.

    ERIC Educational Resources Information Center

    Gold, Ben K.

    In order to investigate patterns of persistence in courses taken by day students at Los Angeles City College, class enrollment data were gathered at the end of the third week of the Fall 1978 semester, at the first and second census weeks, and on the last day of the semester. Additionally, the number of students receiving final grades other than W…

  17. Risk factors for frequent falls in people with Parkinson's disease.

    PubMed

    Paul, Serene S; Allen, Natalie E; Sherrington, Cathie; Heller, Gillian; Fung, Victor S C; Close, Jacqueline C T; Lord, Stephen R; Canning, Colleen G

    2014-01-01

    Fall frequency varies among individuals with Parkinson's disease (PD). We aimed to determine whether risk factors that distinguish PD fallers from non-fallers are influenced by frequent falls. 205 people with PD participated in a 6-month prospective study. Factors in previously published fall risk models were analyzed for their associations with fall rates and frequent fallers. Fall history, freezing and impaired reactive balance were associated with fall rates and the proportion of frequent fallers (p < 0.05). These models were highly accurate in discriminating frequent fallers (area under curve 0.84-0.87). Interventions to manage freezing and reduce balance impairment may reduce fall frequency.

  18. Acid deposition in east Asia

    SciTech Connect

    Phadnis, M.J.; Carmichael, G.R.; Ichikawa, Y.

    1996-12-31

    A comparison between transport models was done to study the acid deposition in east Asia. The two models in question were different in the way the treated the pollutant species and the way simulation was carried out. A single-layer, trajectory model with simple (developed by the Central Research Institute of Electric Power Industry (CRIEPI), Japan) was compared with a multi-layered, eulerian type model (Sulfur Transport Eulerian Model - II [STEM-II]) treating the chemical processes in detail. The acidic species used in the simulation were sulfur dioxide and sulfate. The comparison was done for two episodes: each a month long in winter (February) and summer (August) of 1989. The predicted results from STEM-II were compared with the predicted results from the CRIEPI model as well as the observed data at twenty-one stations in Japan. The predicted values from STEM-II were similar to the ones from the CRIEPI results and the observed values in regards to the transport features. The average monthly values of SO{sub 2} in air, sulfate in air and sulfate in precipitation were in good agreement. Sensitivity studies were carried out under different scenarios of emissions, dry depositions velocities and mixing heights. The predicted values in these sensitivity studies showed a strong dependence on the mixing heights. The predicted wet deposition of sulfur for the two months is 0.7 gS/m2.mon, while the observed deposition is around 1.1 gS/m2.mon. It was also observed that the wet deposition on the Japan sea side of the islands is more than those on the Pacific side and the Okhotsk sea, mainly because of the continental outflow of pollutant air masses from mainland China and Korea. The effects of emissions from Russia and volcanoes were also evaluated.

  19. Cold air systems: Sleeping giant

    SciTech Connect

    MacCracken, C.D. )

    1994-04-01

    This article describes how cold air systems help owners increase the profits from their buildings by reducing electric costs and improving indoor air quality through lower relative humidity levels. Cold air distribution involves energy savings, cost savings, space savings, greater comfort, cleaner air, thermal storage, tighter ducting, coil redesign, lower relative humidities, retrofitting, and improved indoor air quality (IAQ). It opens a door for architects, engineers, owners, builders, environmentalists, retrofitters, designers, occupants, and manufacturers. Three things have held up cold air's usage: multiple fan-powered boxes that ate up the energy savings of primary fans. Cold air room diffusers that provided inadequate comfort. Condensation from ducts, boxes, and diffusers. Such problems have been largely eliminated through research and development by utilities and manufacturers. New cold air diffusers no longer need fan powered boxes. It has also been found that condensation is not a concern so long as the ducts are located in air conditioned space, such as drop ceilings or central risers, where relative humidity falls quickly during morning startup.

  20. MOUNTAIN ACID DEPOSITION PROGRAM (MADPRO): CLOUD DEPOSITION TO THE APPALACHIAN MOUNTAINS, 1994 THROUGH 1999

    EPA Science Inventory

    The mountain Acid Deposition Program (MADPro) was initiated in 1993 as part of the research necessary to support the objectives of the Clean Air Status and Trends Network (CASTNet), which was created to address the requirements of the Clean Air Act Amendments (CAAA). The two ma...

  1. iFall: an Android application for fall monitoring and response.

    PubMed

    Sposaro, Frank; Tyson, Gary

    2009-01-01

    Injuries due to falls are among the leading causes of hospitalization in elderly persons, often resulting in a rapid decline in quality of life or death. Rapid response can improve the patients outcome, but this is often lacking when the injured person lives alone and the nature of the injury complicates calling for help. This paper presents an alert system for fall detection using common commercially available electronic devices to both detect the fall and alert authorities. We use an Android-based smart phone with an integrated tri-axial accelerometer. Data from the accelerometer is evaluated with several threshold based algorithms and position data to determine a fall. The threshold is adaptive based on user provided parameters such as: height, weight, and level of activity. The algorithm adapts to unique movements that a phone experiences as opposed to similar systems which require users to mount accelerometers to their chest or trunk. If a fall is suspected a notification is raised requiring the user's response. If the user does not respond, the system alerts pre-specified social contacts with an informational message via SMS. If a contact responds the system commits an audible notification, automatically connects, and enables the speakerphone. If a social contact confirms a fall, an appropriate emergency service is alerted. Our system provides a realizable, cost effective solution to fall detection using a simple graphical interface while not overwhelming the user with uncomfortable sensors.

  2. Maxillofacial Fractures due to Falls: does Fall Modality Determine the Pattern of Injury?

    PubMed Central

    Boffano, Paolo; Bianchi, Francesca A.; Zavattero, Emanuele

    2014-01-01

    ABSTRACT Objectives In several epidemiological studies of maxillofacial trauma, falls were one of the most frequent causes of facial injury. The aim of this study is to analyse the patterns of fall-related maxillofacial injuries based on the height of the fall. Material and Methods Using a systematic computer-assisted database of patients hospitalised with maxillofacial fractures, only those with fall-related injuries were considered. The falls were divided into four groups: falls from slipping, tripping or stumbling (STSF), loss of consciousness (LOCF), stairs (SAF), and height (HF). Data on the age, gender, fracture site, Facial Injury Severity Scale (FISS), facial lacerations, associated lesions, type of treatment, and length of hospital stay were also analysed. Results This study included 557 patients (338 males, 219 females; average age 51.5 years [range 4 - 99 years]). In the over 60 age group, females were more prevalent in STSF than males. According to aetiology, STSF was the most frequent cause of maxillofacial fractures (315 patients; 56.5%) followed by LOCF (157; 28.2%), HF (55; 9.9%), and SAF (30; 5.4%). The middle third of the face was affected most frequently. After LOCF, however, the inferior third was prevalently involved. The majority of associated fractures, as well as the most severe injuries and greatest rate of facial lacerations, occurred secondary to HF. Conclusions This study showed that fracture severity and site are influenced not only by patient age, but also by the nature of the fall. PMID:25635212

  3. Myths and Misconceptions in Fall Protection

    SciTech Connect

    Epp, R J

    2006-02-23

    Since 1973, when OSHA CFRs 1910 and 1926 began to influence the workplace, confusion about the interpretation of the standards has been a problem and fall protection issues are among them. This confusion is verified by the issuance of 351 (as of 11/25/05) Standard Interpretations issued by OSHA in response to formally submitted questions asking for clarification. Over the years, many workers and too many ES&H Professionals have become 'self-interpreters', reaching conclusions that do not conform to either the Standards or the published Interpretations. One conclusion that has been reached by the author is that many ES&H Professionals are either not aware of, or do not pay attention to the Standard Interpretations issued by OSHA, or the State OSHA interpretation mechanism, whoever has jurisdiction. If you fall in this category, you are doing your organization or clients a disservice and are not providing them with the best information available. Several myths and/or misconceptions have been promulgated to the point that they become accepted fact, until an incident occurs and OSHA becomes involved. For example, one very pervasive myth is that you are in compliance as long as you maintain a distance of 6 feet from the edge. No such carte blanche rule exists. In this presentation, this myth and several other common myths/misconceptions will be discussed. This presentation is focused only on Federal OSHA CFR1910 Subpart D--Walking-Working Surfaces, CFR1926 Subpart M--Fall Protection and the Fall Protection Standard Interpretation Letters. This presentation does not cover steel erection, aerial lifts and other fall protection issues. Your regulations will probably be different than those presented if you are operating under a State plan.

  4. Pulsed Nd:YAG laser deposition of ruthenium thin films

    NASA Astrophysics Data System (ADS)

    Wai Keat, Lee

    Ruthenium (Ru) is one of the noble air-stable transition metals, which has excellent thermal chemical stability, low electrical resistivity, and relatively high work function near the valence band edge of Si. Recently, Ru has been introduced into the semiconductor industries as a result of the interesting chemical, physical, and electrical properties it possessed. So far, investigations of ruthenium films have been centered on material properties of Ru layers, growth using direct current/radiofrequency (DC/RF) magnetron sputtering, and chemical vapor deposition. However, comparatively little work has been carried out using the pulsed laser deposition (PLD) technique. In this research work, the growth of Ru film using PLD was investigated. The Ru films were deposited on silicon (Si) substrates employing 355 nm pulsed Nd:YAG laser source. Laser fluence ranged from 2 to 8 J/cm2 was employed, with deposition duration from 5 to 180 minutes under high vacuum condition. Optical emission spectroscopy (OES) was employed to study the species and purity of the plasma during the deposition. It was observed that intensity of the Ru species spectra increased with increasing laser fluence and more prominent after laser fluence of 4 J/cm2. No impurities were observed. Film thicknesses ranging from 15 to 280 nm were obtained. As the deposition duration and the laser fluence increased, the thickness of the deposited Ru films increased. It is observed that there was a critical deposition duration value, and this value increases as the laser fluence increased. X-ray diffraction (XRD) spectra showed Ru with crystalline orientation of (101), (100), and (002) peaks. The XRD results revealed an enhanced diffraction peak when film thickness increased, under all laser fluences. Grain sizes were deduced from the XRD data by using the Scherrer's formula and the values fall in the range of 20 to 35 nm for the film thickness covering from 50 nm to 250 nm. Besides, the electrical properties of

  5. Effectiveness of blast-mitigation for rock fall endangered critical infrastructure using terrestrial laser scanning (LIDAR).

    NASA Astrophysics Data System (ADS)

    Kos, A.; Lunghi, A.; Naenni, C.; Conforti, D.; Tompkinson, W.

    2009-04-01

    Following a national rock fall risk assessment undertaken by the Swiss Federal Roads Office (FEDRO) a potential rock fall area located above the San Bernardino highway (A13) at Brusei, Canton Graubünden was identified. The rockslope at Brusei was characterized by a previous record of rock fall, large overhanging outcrops and open tension cracks up to 2 metres. Combined with the fact that the A13 is a critical north-south traffic corridor in Switzerland and the geological situation, the Public Works Department of the Canton Graubünden made the decision to mitigate the rock fall risk with the use of explosives. We report on the use of terrestrial laser scanning for evaluating the effectiveness of mitigation using explosives for the protection of critical infrastructure. Although modern blast mitigation methods allow for accurate control on removed volumes of rock, it is important to calculate how much was actually removed particularly when protection structures, such as rock fall galleries are located in the transit/deposition zone of the blasted area. High resolution laser scanning is an appropriate technology for monitoring the pre- and post blast situation and provides the basis for: 1) Geological investigations for understanding the initial cause of instabilities; 2) Monitoring the formation of potential new instabilities following blast mitigation; and 3) Integration with other spatial monitoring technologies, such as ground-based radar interferometry.

  6. CASTNet mountain acid deposition monitoring program

    SciTech Connect

    Bowser, J.J.; Anderson, J.B.; Edgerton, E.S.; Mohnen, V.; Baumgardener, R.

    1994-12-31

    Concern over the influence of air pollution on forest decline has led the USEPA to establish the Mountain Acid Deposition Monitoring Program (MADMP) to quantify total deposition at high altitudes, i.e., above cloud base. Clouds can be a major source of atmospheric deposition to sensitive, mountain ecosystems. This program is a part of the Clean Air Status and Trends Network (CASTNet), a national assessment of the effects of the 1990 Clean Air Act. The objectives of MADMP are to estimate total deposition, measure cloud chemistry, and characterize spacial and temporal trends at four selected high altitude sites in the Eastern US. Four MADMP sites have been established for the 1994 field season: Clingman`s Dome, Great Smoky Mountain Nat. Park, TN; Slide Mountain, Catskill State Park, NY; Whiteface Mountain, Adirondack State Park, NY; and Whitetop Mountain, Mt. Rogers Nat`l Recreational Area, VA. An automated cloud collection system will be utilized in combination with continuous measurements of cloud liquid water content in order to estimate cloudwater deposition. Other relevant data will include continuous meteorological measurements, ozone and sulfur dioxide concentrations, wet deposition from rainfall analysis, and dry deposition from filter pack analysis. Quality assurance and quality control measures will be employed to maximize accuracy and precision.

  7. DEPOSITION OF METAL ON NONMETAL FILAMENT

    DOEpatents

    Magel, T.T.

    1959-02-10

    A method is described for purifying metallic uranium by passing a halogen vapor continuously over the impure uranium to form uranium halide vapor and immediately passing the halide vapor into contact with a nonmetallic refractory surface which is at a temperature above the melting point of uranium metal. The halide is decomposed at the heated surface depositing molten metal, which collects and falls into a receiver below.

  8. Utilization of Residence Hall Facilities, Fall 1986, with Trends from Fall 1977. Report No. 9-87.

    ERIC Educational Resources Information Center

    State Univ. of New York, Albany. Central Staff Office of Institutional Research.

    Data on the utilization of residence hall facilities at campuses of the State University of New York are presented for fall 1986, with summary data for fall 1977 through fall 1986. In addition to trend data for each college and college type, graphic displays of percent utilization of residence hall facilities are provided. Tables for fall 1986…

  9. A wavelet-based approach to fall detection.

    PubMed

    Palmerini, Luca; Bagalà, Fabio; Zanetti, Andrea; Klenk, Jochen; Becker, Clemens; Cappello, Angelo

    2015-01-01

    Falls among older people are a widely documented public health problem. Automatic fall detection has recently gained huge importance because it could allow for the immediate communication of falls to medical assistance. The aim of this work is to present a novel wavelet-based approach to fall detection, focusing on the impact phase and using a dataset of real-world falls. Since recorded falls result in a non-stationary signal, a wavelet transform was chosen to examine fall patterns. The idea is to consider the average fall pattern as the "prototype fall".In order to detect falls, every acceleration signal can be compared to this prototype through wavelet analysis. The similarity of the recorded signal with the prototype fall is a feature that can be used in order to determine the difference between falls and daily activities. The discriminative ability of this feature is evaluated on real-world data. It outperforms other features that are commonly used in fall detection studies, with an Area Under the Curve of 0.918. This result suggests that the proposed wavelet-based feature is promising and future studies could use this feature (in combination with others considering different fall phases) in order to improve the performance of fall detection algorithms. PMID:26007719

  10. Influences on modern multifactorial falls prevention interventions and fear of falling in non-frail older adults: a literature review.

    PubMed

    Svantesson, Ulla; Babagbemi, Buki; Foster, Lakicia; Alricsson, Marie

    2014-10-01

    This review explores underlying features that may influence fear of falling and the effectiveness of multifactorial falls prevention programs in community dwelling non-frail adults aged 65 and older. It also examines the interrelationship between fear of falling and multifactorial falls prevention interventions. A literature search of medical databases was conducted to identify articles that address the fear of falling and multifactorial programs as either a primary or secondary component of their findings. Multifactorial interventions were assessed in terms of their program content, design, demographics, implementation techniques, and cost-effectiveness. Falls are a common, but preventable, cause of morbidity and injury in older adults 65 and over. In addition to physiological variables, fear of falling and self-efficacy are psychosocial factors that impact the incidence of falls in this population. Addressing fear of falling in addition to physiological parameters may influence the success of multifactorial falls prevention programs for adults 65 and over.

  11. Cross-Sectional and Longitudinal Risk Factors for Falls, Fear of Falling, and Falls Efficacy in a Cohort of Middle-Aged African Americans

    ERIC Educational Resources Information Center

    Anderson, Elena M.; Wolinsky, Fredric D.; Miller, J. Phillip; Wilson, Margaret-Mary G.; Malmstrom, Theodore K.; Miller, Douglas K.

    2006-01-01

    Purpose: The purpose of this study is to cross-sectionally and longitudinally identify risk factors for falls, fear of falling, and falls efficacy in late-middle-aged African Americans. Design and Methods: We performed in-home assessments on a probability sample of 998 African Americans and conducted two annual follow-up interviews. Multiple…

  12. Changes in FTSE in Selected Occupational Areas by Student Sex: Fall 1972, Fall 1977, and Fall 1982. Report No. 82-16.

    ERIC Educational Resources Information Center

    Bresler, Marilyn

    Data are provided in this report on the changes in the sexual composition of full-time student enrollments in selected occupational areas in the Maricopa County Community College District (MCCCD). The report provides figures on male and female enrollments for fall 1972, fall 1977, and fall 1982 in eight areas: Administration of Justice,…

  13. 40 CFR 81.88 - Billings Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Quality Control Regions § 81.88 Billings Intrastate Air Quality Control Region. The Metropolitan Billings Intrastate Air Quality Control Region (Montana) has been renamed the Billings Intrastate Air Quality Control... to by Montana authorities as follows: Sec. 481.168Great Falls Intrastate Air Quality Control...

  14. Air resources

    SciTech Connect

    1995-10-01

    This section describes the ambient (surrounding) air quality of the TVA region, discusses TVA emission contributions to ambient air quality, and identifies air quality impacts to human health and welfare. Volume 2 Technical Document 2, Environmental Consequences, describes how changes in TVA emissions could affect regional air quality, human health, environmental resources, and materials. The primary region of the affected environment is broadly defined as the state of Tennessee, as well as southern Kentucky, western Virginia, southern West Virginia, western North Carolina, and northern Georgia, Alabama, and Mississippi. This area represents the watershed of the Tennessee River and the 201 counties of the greater TVA service area. Emissions from outside the Tennessee Valley region contribute to air quality in the Valley. Also, TVA emissions are transported outside the Valley and have some impact on air quality beyond the primary study area. Although the study area experiences a number of air quality problems, overall air quality is good.

  15. Correlation of sea level falls interpreted from atoll stratigraphy with turbidites in adjacent basins

    SciTech Connect

    Lincoln, J.M. )

    1990-05-01

    Past sea levels can be derived from any atoll subsurface sediments deposited at or near sea level by determining the ages of deposition and correcting the present depths to the sediments for subsidence of the underlying edifice since the times of deposition. A sea level curve constructed by this method consists of discontinuous segments, each corresponding to a period of rising relative sea level and deposition of a discrete sedimentary package. Discontinuities in the sea level curve derived by this method correspond to relative sea level falls and stratigraphic hiatuses in the atoll subsurface. During intervals of relative sea level fall an atoll emerges to become a high limestone island. Sea level may fluctuate several times during a period of atoll emergence to become a high limestone island. Sea level may fluctuate several times during a period of atoll emergence without depositing sediments on top of the atoll. Furthermore, subaerial erosion may remove a substantial part of the depositional record of previous sea level fluctuations. For these reasons the authors must look to the adjacent basins to complement the incomplete record of sea level change recorded beneath atolls. During lowstands of sea level, faunas originally deposited near sea level on an atoll may be eroded and redeposited as turbidites in deep adjacent basins. Three such turbidites penetrated during deep-sea drilling at Sites 462 and 315 in the central Pacific correlate well with a late Tertiary sea level curve based on biostratigraphic ages and {sup 87}Sr/{sup 86}Sr chronostratigraphy for core from Enewetak Atoll in the northern Marshall Islands. Further drilling of the archipelagic aprons adjacent to atolls will improve the sea level history that may be inferred from atoll stratigraphy.

  16. Exercise in preventing falls and fall related injuries in older people: a review of randomised controlled trials

    PubMed Central

    Gardner, M.; Robertson, M; Campbell, A

    2000-01-01

    Objective—To assess the effectiveness of exercise programmes in preventing falls (and/or lowering the risk of falls and fall related injuries) in older people. Design—A review of controlled clinical trials designed with the aim of lowering the risk of falling and/or fall injuries through an exercise only intervention or an intervention that included an exercise component Main outcome measures—Falls, fall related injuries, time between falls, costs, cost effectiveness. Subjects—A total of 4933 men and women aged 60 years and older. Results—Eleven trials meeting the criteria for inclusion were reviewed. Eight of these trials had separate exercise interventions, and three used interventions with an exercise programme component. Five trials showed a significant reduction in the rate of falls or the risk of falling in the intervention group. Conclusions—Exercise is effective in lowering falls risk in selected groups and should form part of falls prevention programmes. Lowering fall related injuries will reduce health care costs but there is little available information on the costs associated with programme replication or the cost effectiveness of exercise programmes aimed at preventing falls in older people. Key Words: exercise; elderly; falls; cost effectiveness PMID:10690444

  17. Atmospheric deposition maps for the Rocky Mountains

    USGS Publications Warehouse

    Nanus, L.; Campbell, D.H.; Ingersoll, G.P.; Clow, D.W.; Mast, M.A.

    2003-01-01

    Variability in atmospheric deposition across the Rocky Mountains is influenced by elevation, slope, aspect, and precipitation amount and by regional and local sources of air pollution. To improve estimates of deposition in mountainous regions, maps of average annual atmospheric deposition loadings of nitrate, sulfate, and acidity were developed for the Rocky Mountains by using spatial statistics. A parameter-elevation regressions on independent slopes model (PRISM) was incorporated to account for variations in precipitation amount over mountainous regions. Chemical data were obtained from the National Atmospheric Deposition Program/National Trends Network and from annual snowpack surveys conducted by the US Geological Survey and National Park Service, in cooperation with other Federal, State and local agencies. Surface concentration maps were created by ordinary kriging in a geographic information system, using a local trend and mathematical model to estimate the spatial variance. Atmospheric-deposition maps were constructed at 1-km resolution by multiplying surface concentrations from the kriged grid and estimates of precipitation amount from the PRISM model. Maps indicate an increasing spatial trend in concentration and deposition of the modeled constituents, particularly nitrate and sulfate, from north to south throughout the Rocky Mountains and identify hot-spots of atmospheric deposition that result from combined local and regional sources of air pollution. Highest nitrate (2.5-3.0kg/ha N) and sulfate (10.0-12.0kg/ha SO4) deposition is found in northern Colorado.

  18. Nitrogen Deposition to the Tampa Bay Watershed

    NASA Astrophysics Data System (ADS)

    Poor, N.; Tate, P.; Begum, M.; Evans, M.; Campbell, S.; Bhethanabotla, V.; Bollinger, C.; Ball, A.

    2003-12-01

    An earlier estimate of the direct deposition of nitrogen to Tampa Bay was ~7 kg-N/ha/yr and included the wet deposition of rainfall nitrate and ammonium and the dry deposition of nitric acid, ammonia, nitrate and ammonium. Rainfall and ambient air concentration measurements were made at an urban site within 50 m of Tampa Bay. Rainfall samples were obtained daily from a wet-only precipitation collector, which was part of the NADP AIRMoN. Ambient air concentrations of gases and fine particles were determined from an annular denuder system, operated at 10 l/min for 24-hr/day on a 1-in-6 day schedule, and dry deposition velocities were calculated with the NOAA buoy model using over water meteorological data. This estimate is revised upward to ~8 kg-N/ha/yr and includes corrections for nitric acid collection inefficiencies, the addition of coarse particle nitrate based on mircoorfice impactor measurements, and improved fine and coarse particle deposition velocity estimates from an integrated NOAA buoy/Williams model. With gas, fine aerosol and coarse particle measurements made at a peri-suburban site coupled with deposition velocities from a resistance model, and rainfall concentration measurements from a rural NADP NTN site in Sarasota County, the estimated total nitrogen deposition to the surface of the watershed is ~16 kg-N/ha/yr. The ratios of dry to wet deposition rates are ~1:1 over water and ~4:1 over land.

  19. Air Pollution.

    ERIC Educational Resources Information Center

    Gilpin, Alan

    A summary of one of our most pressing environmental problems, air pollution, is offered in this book by the Director of Air Pollution Control for the Queensland (Australia) State Government. Discussion of the subject is not restricted to Queensland or Australian problems and policies, however, but includes analysis of air pollution the world over.…

  20. Survey on Fall Detection and Fall Prevention Using Wearable and External Sensors

    PubMed Central

    Delahoz, Yueng Santiago; Labrador, Miguel Angel

    2014-01-01

    According to nihseniorhealth.gov (a website for older adults), falling represents a great threat as people get older, and providing mechanisms to detect and prevent falls is critical to improve people's lives. Over 1.6 million U.S. adults are treated for fall-related injuries in emergency rooms every year suffering fractures, loss of independence, and even death. It is clear then, that this problem must be addressed in a prompt manner, and the use of pervasive computing plays a key role to achieve this. Fall detection (FD) and fall prevention (FP) are research areas that have been active for over a decade, and they both strive for improving people's lives through the use of pervasive computing. This paper surveys the state of the art in FD and FP systems, including qualitative comparisons among various studies. It aims to serve as a point of reference for future research on the mentioned systems. A general description of FD and FP systems is provided, including the different types of sensors used in both approaches. Challenges and current solutions are presented and described in great detail. A 3-level taxonomy associated with the risk factors of a fall is proposed. Finally, cutting edge FD and FP systems are thoroughly reviewed and qualitatively compared, in terms of design issues and other parameters. PMID:25340452

  1. Milestones in gait, balance, and falling.

    PubMed

    Nutt, John G; Horak, Fay B; Bloem, Bastiaan R

    2011-05-01

    Gait, balance, and falls have become increasingly common topics of published articles in the Movement Disorders journal since its launch in 1986. This growth represents an increasing awareness of the importance of mobility to patients' quality of life. New methods have become available that allow for accurate measurement of many aspects for gait and balance. This has led to new concepts of understanding gait and balance disorders. Neuroimaging has begun to reveal the neural circuitry underlying gait and balance. The physiology and pathophysiology of balance and gait are beginning to tease out the many processes involved in mobility and how they may be disrupted by disease processes. With these advances, the old therapeutic nihilism that characterized the clinician's approach to falls and gait disorders is disappearing, as innovative physiotherapy, exercise, drugs, and deep brain stimulation are being employed for gait and balance disorders. PMID:21626560

  2. Droplet impact on falling liquid films

    NASA Astrophysics Data System (ADS)

    Matar, Omar; Che, Zhizhao; Zadrazil, Ivan; Hewitt, Geoffrey; Markides, Christos

    2013-11-01

    Droplet impact is a ubiquitous phenomenon in nature, and has a wide range of applications; these include inkjet printing, spray painting, and surface cleaning. In this study, we examine the impact of droplets on falling liquid films, which is an event that occurs in various two-phase flows, such as annular flows and spray cooling. High-speed photography is used to visualise droplet impact, and associated phenomena, on a uniform falling liquid film, which is created on a flat substrate with controllable thickness and flow speed. Different phenomena are observed and analysed for droplet impact at different impact speeds, angles, and film thicknesses and flow speeds. The results of the present work are part of a programme to elucidate the complex dynamics of multiphase flows and to develop validated numerical tools for accurate predictions. EPSRC Programme Grant EP/K003976/1.

  3. Conditioning of sandhill cranes during fall migration

    USGS Publications Warehouse

    Krapu, Gary L.; Johnson, Douglas H.

    1990-01-01

    Body mass of adult female and male sandhill cranes (Grus canadensis) increased an average of 17 and 20%, respectively, from early September to late October on staging areas in central North Dakota and varied by year. Increases in body mass averaged 550 and 681 g among female and male G. c. canadensis, respectively, and 616 and 836 g among female and male G. c. rowani. Adult and juvenile G. c. rowani were lean at arrival, averaging 177 and 83 g of fat, respectively, and fat reserves increased to 677 and 482 g by mid-October. Fat-free dry mass increased by 12% among juveniles, reflecting substantial growth, but remained constant among adults. The importance of fall staging areas as conditioning sites for sandhill cranes, annual variation in body mass, and vulnerability of cranes to habitat loss underscore the need to monitor status of fall staging habitat in the northern plains region and to take steps to maintain suitable habitat where necessary.

  4. Exploring ethnic and racial differences in falls among older adults.

    PubMed

    Han, Benjamin H; Ferris, Rosie; Blaum, Caroline

    2014-12-01

    Falls are common events that threaten the independence and health of older adults. Studies have found a wide range of fall statistics in different ethnic and racial groups throughout the world. These studies suggest that fall rates may differ between different racial and ethnic groups. Studies also suggest that the location of falls, circumstances of falls, and particular behaviors may also be different by population. Also migration to new locations may alter an individual's fall risk. However, there are few studies that directly compare ethnic and racial differences in falls statistics or examine how known fall risk factors change based on race and ethnicity. This paper reviews the existing literature on how falls may differ between different racial and ethnic groups, highlights gaps in the literature, and explores directions for future research. The focus of this paper is community dwelling older adults and immigrant populations in the United States.

  5. A Wavelet-Based Approach to Fall Detection

    PubMed Central

    Palmerini, Luca; Bagalà, Fabio; Zanetti, Andrea; Klenk, Jochen; Becker, Clemens; Cappello, Angelo

    2015-01-01

    Falls among older people are a widely documented public health problem. Automatic fall detection has recently gained huge importance because it could allow for the immediate communication of falls to medical assistance. The aim of this work is to present a novel wavelet-based approach to fall detection, focusing on the impact phase and using a dataset of real-world falls. Since recorded falls result in a non-stationary signal, a wavelet transform was chosen to examine fall patterns. The idea is to consider the average fall pattern as the “prototype fall”.In order to detect falls, every acceleration signal can be compared to this prototype through wavelet analysis. The similarity of the recorded signal with the prototype fall is a feature that can be used in order to determine the difference between falls and daily activities. The discriminative ability of this feature is evaluated on real-world data. It outperforms other features that are commonly used in fall detection studies, with an Area Under the Curve of 0.918. This result suggests that the proposed wavelet-based feature is promising and future studies could use this feature (in combination with others considering different fall phases) in order to improve the performance of fall detection algorithms. PMID:26007719

  6. Hollow Nodules Gas Escape Sedimentary Structures in Lacustrine Deposits on Earth and Gale Crater

    NASA Astrophysics Data System (ADS)

    Bonaccorsi, R.; Willson, D.; Fairen, A. G.; Baker, L.; McKay, C.; Zent, A.; Mahaffy, P. R.

    2015-12-01

    Curiosity's Mastcam and MAHLI instruments in Gale Crater (GC) imaged mm-sized circular rimmed hollow nodules (HNs) (Figure 1A), pitting the Sheepbed mudstone of Yellowknife Bay Formation [1,2]. HNs are significantly smaller than the solid nodules within the outcrop, with an external mean diameter of 1.2 mm and an interior one of 0.7 mm [2] Several formation mechanisms of HNs have been discussed, such as: (1) Diagenetic dissolution of soluble mineral phases; or, (2) Gas bubbles released shortly after sediment deposition [1-3]. In an ephemeral pond in Ubehebe Crater (Death Valley, CA) we observed the formation of hollow nodule sedimentary structures produced by gas bubbles (Figure 1C) preserved in smectite-rich mud that are strikingly similar to those imaged in GC (Figure 1A). This finding supports the gas bubble hypothesis [2]. Ubehebe Crater (UC) surface sediment hollow nodules were sampled, imaged, and their internal diameter measured (200 hollow structures) showing similar shape, distribution, and composition to those imaged by Curiosity in GC. UC in-situ observations suggest the gas bubbles were generated within the slightly reducing ephemerally submerged mud. These intra-crater deposits remain otherwise extremely dry year round, i.e., Air_rH ~2-5%; ground H2O wt%: 1-2%; Summer air/ground T: 45-48ºC/67-70ºC [4-5]. Data from the Sample Analysis at Mars (SAM), CheMin, and ChemCam instruments onboard the rover revealed that HNs-bearing mudstone are rich in smectite clay e.g., ~18-20% [6,7] deposited in a neutral to mildly alkaline environment, capturing a period when the surface was potentially habitable [1]. The UC HNs-hosting deposits are also rich in smectite clays (~30%) and occur in an ephemeral shallow freshwater setting [4-5]. If present, surface hollow nodules are easy to find in dry clay-rich mud in lacustrine sediments, so they could represent a new indicator of ephemeral but habitable/inhabited environments on both Earth and early Mars. References: [1

  7. Modeling seasonal migration of fall armyworm moths

    NASA Astrophysics Data System (ADS)

    Westbrook, J. K.; Nagoshi, R. N.; Meagher, R. L.; Fleischer, S. J.; Jairam, S.

    2016-02-01

    Fall armyworm, Spodoptera frugiperda (J.E. Smith), is a highly mobile insect pest of a wide range of host crops. However, this pest of tropical origin cannot survive extended periods of freezing temperature but must migrate northward each spring if it is to re-infest cropping areas in temperate regions. The northward limit of the winter-breeding region for North America extends to southern regions of Texas and Florida, but infestations are regularly reported as far north as Québec and Ontario provinces in Canada by the end of summer. Recent genetic analyses have characterized migratory pathways from these winter-breeding regions, but knowledge is lacking on the atmosphere's role in influencing the timing, distance, and direction of migratory flights. The Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model was used to simulate migratory flight of fall armyworm moths from distinct winter-breeding source areas. Model simulations identified regions of dominant immigration from the Florida and Texas source areas and overlapping immigrant populations in the Alabama-Georgia and Pennsylvania-Mid-Atlantic regions. This simulated migratory pattern corroborates a previous migratory map based on the distribution of fall armyworm haplotype profiles. We found a significant regression between the simulated first week of moth immigration and first week of moth capture (for locations which captured ≥10 moths), which on average indicated that the model simulated first immigration 2 weeks before first captures in pheromone traps. The results contribute to knowledge of fall armyworm population ecology on a continental scale and will aid in the prediction and interpretation of inter-annual variability of insect migration patterns including those in response to climatic change and adoption rates of transgenic cultivars.

  8. Free fall - A partial unique motion environment

    NASA Technical Reports Server (NTRS)

    Graybiel, A.

    1980-01-01

    Conditions leading to the elicitation of motion sickness have been divided into two main categories: partial motion environments, in which head movements are required to elicit motion sickness, and complete motion environments, in which independent movements of the head are not required for the production of symptoms. It is postulated that, according to this categorization, free fall constitutes a partial motion environment. In support of this hypothesis evidence is reviewed from Skylab missions, experiments in parabolic flight, and ground-based studies.

  9. Inpatient Falls: Improving assessment, documentation, and management.

    PubMed

    Nelson, Eleanor; Reynolds, Patrick

    2015-01-01

    A frequently occurring job during on-call and out-of-hours shifts is reviewing a patient following a fall with this often being the responsibility of the most junior and inexperienced doctors. Following a pilot audit we identified inconsistencies in medical assessment and documentation, with 50% of expected data points not recorded. Failure to complete a thorough assessment can lead to missed injuries, prolonged length of stay, and litigation. Using the plan, do, study, act (PDSA) cycle model this project sought to address this through providing teaching to junior doctors and the development of a pro-forma. Three style cycles of data collection were performed; a formal baseline dataset, after delivering a teaching session to new junior doctors and following the trial of the new fall pro-forma. We selected 15 to 17 patient notes to review at random during a one month period for each data collection cycle and compared the medical assessment to the standards outlined by the National Patient Safety Agency (NPSA) guidelines.[1] There were two key areas of improvement identified following the teaching session and introduction of the proforma. Documentation of a fall history was improved by nearly 30% being recorded in 100% of cases after the interventions. Documentation of a thorough musculoskeletal examination was improved from being recorded in just 54% of cases to 77% of cases; it was recorded in 100% of the cases where the proforma was used. The project demonstrated the need to improve documentation and assessment of a patient who has fallen. Initial data collection has shown that assessment and documentation were improved providing teaching to junior doctors and by use of the document. The pro-forma has since been incorporated into hospital policy and now forms the compulsory documentation expected of the doctors and nurses managing patients following a fall. Ensuring easy access to the proforma and re-auditing after editing the document will be the next steps. PMID

  10. Modeling seasonal migration of fall armyworm moths.

    PubMed

    Westbrook, J K; Nagoshi, R N; Meagher, R L; Fleischer, S J; Jairam, S

    2016-02-01

    Fall armyworm, Spodoptera frugiperda (J.E. Smith), is a highly mobile insect pest of a wide range of host crops. However, this pest of tropical origin cannot survive extended periods of freezing temperature but must migrate northward each spring if it is to re-infest cropping areas in temperate regions. The northward limit of the winter-breeding region for North America extends to southern regions of Texas and Florida, but infestations are regularly reported as far north as Québec and Ontario provinces in Canada by the end of summer. Recent genetic analyses have characterized migratory pathways from these winter-breeding regions, but knowledge is lacking on the atmosphere's role in influencing the timing, distance, and direction of migratory flights. The Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model was used to simulate migratory flight of fall armyworm moths from distinct winter-breeding source areas. Model simulations identified regions of dominant immigration from the Florida and Texas source areas and overlapping immigrant populations in the Alabama-Georgia and Pennsylvania-Mid-Atlantic regions. This simulated migratory pattern corroborates a previous migratory map based on the distribution of fall armyworm haplotype profiles. We found a significant regression between the simulated first week of moth immigration and first week of moth capture (for locations which captured ≥ 10 moths), which on average indicated that the model simulated first immigration 2 weeks before first captures in pheromone traps. The results contribute to knowledge of fall armyworm population ecology on a continental scale and will aid in the prediction and interpretation of inter-annual variability of insect migration patterns including those in response to climatic change and adoption rates of transgenic cultivars.

  11. Atmospheric deposition of nutrients, pesticides, and mercury in Rocky Mountain National Park, Colorado, 2002

    USGS Publications Warehouse

    Mast, M. Alisa; Campbell, Donald H.; Ingersoll, George P.; Foreman, William T.; Krabbenhoft, David P.

    2003-01-01

    summer precipitation than in winter snow, between 80 to 90 percent of the annual pesticide deposition occurs during summer. Mercury deposition to Loch Vale was estimated at 7.1 ?g/m2 (micrograms per square meter) of which nearly 70 percent of the annual mercury deposition occurred during summer. Despite the fact that most precipitation at high-elevations falls during winter, these results emphasize the importance of monitoring precipitation chemistry during summer to improve estimates of contaminant deposition to high-elevation ecosystems in Rocky Mountain National Park. Air-parcel back trajectories were calculated using an atmospheric transport model to identify potential source regions for contaminants reaching the park. The results indicate that during the winter, the most likely source of contami-nants is from areas northwest of the park, but during summer, contaminants are most likely coming from sources to the southwest and east.

  12. A Second H Chondrite Stream of Falls

    NASA Astrophysics Data System (ADS)

    Wolf, S. F.; Wang, M.-S.; Dodd, R. T.; Lipschutz, M. E.

    1995-09-01

    Earlier, Dodd et al. [1] described a statistically significant concentration of 17 H4-6 chondrite falls in May between 1855 and 1895, that clustered on a year-day plot, indicating a coorbital meteoroid stream or two closely-related ones. Contents of 10 thermally labile trace elements (Rb, Ag, Se, Cs, Te,Zn, Cd, Bi, Tl, In) determined by RNAA demonstrated that 13 of these H Cluster 1 (hereafter HC1) falls are compositionally distinguishable from another 45 non-H Cluster 1 (non-HC1) falls [1] (as are Antarctic samples with nominal terrestrial ages >50 ky [2,3]). This compositional distinguishability is demonstrable using two standard, model-dependent multivariate statistical tests (linear discriminant analysis LDA or logistic regression LR) or the model-independent, randomization-simulation (R-S) methods of Lipschutz and Samuels [4]. Despite petrographic and cosmic ray exposure age variabilities, like Antarctic suites [2] HC1 meteorites seemingly derive from coorbital meteoroids (from their circumstances of fall) and apparently have a common thermal history (reflected in contents of thermally labile trace elements) distinguishable from those of other H4-6 chondrite falls [1]. Other explanations seem inviable [5]. During days 220-300 when streams of large fireballs [6] and near-Earth asteroids [7] occur several H chondrite concentrations are evident (Fig. 1), particularly if petrographic type becomes a criterion [1]. Here, we focus on H Clusters 2 through 4 (HC2-4) containing, respectively, 10 H4-6, 5 H5 and 12 H6 chondrite members, for which full data sets exist because of the generosity of many colleagues/institutions. H chondrite clusters in the same time-span might include samples derived from related parent regions. Hence, we changed our comparison-base to approximate a random background of falls by including only the 34 non-Cluster H chondrites, HC0; this also simplified our calculations. To establish whether this choice impacts our observations, we compared 13

  13. Klamath Falls downtown development geothermal sidewalk snowmelt

    SciTech Connect

    Brown, B.

    1995-10-01

    The Klamuth Falls, Oregon, downtown has seen a period of decline over the past 20 years as businesses have moved to new suburban shopping centers. Downtown business owners and the Klamuth Falls Downtown Redevelopment Agency are working to reverse that trend with a Downtown Streetscape Project intended to make the downtown a more pleasant place to work and do business. The visible elements of the project include new crosswalks with brick pavers, wheelchair ramps at sidewalk corners, new concrete sidewalks with a consistent decorative grid pattern, sidewalk planters for trees and flowers, and antique-style park benches and lighting fixtures. A less visible, but equally valuable feature of the project is the plastic tubing installed under the sidewalks, wheelchair ramps and crosswalks, designed to keep them snow and ice free in the winter. A unique feature of the snowmelt system is the use of geothermal heated water on the return side of the Klamath Falls Geothermal District Heating System, made possible by the recent expansion of the district heating system.

  14. Fatal falls and jumps from motor vehicles.

    PubMed Central

    Williams, A F; Goins, S E

    1981-01-01

    In 1978, 345 persons were killed in the United States in jumps and falls from non-crashing motor vehicles: 64 per cent fell; 15 per cent jumped; and it was not known whether the other 21 per cent jumped or fell. Two hundred and one people had been traveling on the exterior of vehicles, especially truck beds, and almost all of these people fell from their vehicles. The other 144 fatalities involved people in passenger compartments. Many of the falls from compartments occurred when occupants opened doors, or when vehicles changed direction. Seventy-seven per cent of those who fell from passenger compartments were males, and 44 per cent were less than five years old. Among those who jumped from vehicle compartments, 62 per cent were women and all were older than 14 years. Fatal falls and jumps from vehicles could be reduced in a variety of ways. These include legislation to prohibit travel on vehicle exteriors, designing vehicles so that doors cannot be opened when in motion, improving door designs, installing signals that provide warning if doors are not closed completely, and using occupant restraints. PMID:7468860

  15. Fall Down Detection Under Smart Home System.

    PubMed

    Juang, Li-Hong; Wu, Ming-Ni

    2015-10-01

    Medical technology makes an inevitable trend for the elderly population, therefore the intelligent home care is an important direction for science and technology development, in particular, elderly in-home safety management issues become more and more important. In this research, a low of operation algorithm and using the triangular pattern rule are proposed, then can quickly detect fall-down movements of humanoid by the installation of a robot with camera vision at home that will be able to judge the fall-down movements of in-home elderly people in real time. In this paper, it will present a preliminary design and experimental results of fall-down movements from body posture that utilizes image pre-processing and three triangular-mass-central points to extract the characteristics. The result shows that the proposed method would adopt some characteristic value and the accuracy can reach up to 90 % for a single character posture. Furthermore the accuracy can be up to 100 % when a continuous-time sampling criterion and support vector machine (SVM) classifier are used. PMID:26276014

  16. Horton Falls named for Pioneer Hydrologist

    NASA Astrophysics Data System (ADS)

    Schaefer, Vincent

    A beautiful 80-foot waterfall in the Catskill Mountains was recently named after Robert E. Horton (1875-1945), a pioneer hydrologist and active AGU member for many years. Officially named Horton Falls, the waterfall, located a few miles east of Voorheesville, N.Y., in Albany County, was an important part of Horton's hydrological laboratory. The U.S. Board on Geographic Names approved the name at its November 8, 1990 meeting.Horton lived close to the falls and operated his hydrological laboratory at its crest in the old La Grange Grist Mill, which used hydropower generated by the falling waters of the La Grange Mill Pond, originally impounded by a wooden log dam 100 feet upstream of the mill. As far as can be determined, the pioneer La Granges, who built and operated the mill, never used the 85-foot head made available to them by the waterfalls. Horton, however, did, and ran a vertical and a horizontal iron water wheel to spin a DC electricity-generating turbine, which he used for heat, light, and power in his home and laboratory.

  17. Modern Rehabilitation in Osteoporosis, Falls, and Fractures

    PubMed Central

    Dionyssiotis, Yannis; Skarantavos, Grigorios; Papagelopoulos, Panayiotis

    2014-01-01

    In prevention and management of osteoporosis, modern rehabilitation should focus on how to increase muscular and bone strength. Resistance exercises are beneficial for muscle and bone strength, and weight-bearing exercises help maintain fitness and bone mass. In subjects at higher risk for osteoporotic fractures, particular attention should be paid to improving balance – the most important element in falls prevention. Given the close interaction between osteoporosis and falls, prevention of fractures should be based on factors related to bone strength and risk factors for falls. Fractures are the most serious complication of osteoporosis and may be prevented. The use of modern spinal orthosis helps to reduce pain and improve posture. Vibration platforms are used in rehabilitation of osteoporosis, based on the concept that noninvasive, short-duration, mechanical stimulation could have an impact on osteoporosis risk. Pharmacologic therapy should be added for those at high risk of fracture, and vitamin D/calcium supplementation is essential in all prevention strategies. Success of rehabilitation in osteoporotic and fractured subjects through an individualized educational approach optimizes function to the highest level of independence while improving the overall quality of life. PMID:24963273

  18. Falling through the black hole horizon

    NASA Astrophysics Data System (ADS)

    Brustein, Ram; Medved, A. J. M.

    2015-06-01

    We consider the fate of a small classical object, a "stick", as it falls through the horizon of a large black hole (BH). Classically, the equivalence principle dictates that the stick is affected by small tidal forces, and Hawking's quantum-mechanical model of BH evaporation makes essentially the same prediction. If, on the other hand, the BH horizon is surrounded by a "firewall", the stick will be consumed as it falls through. We have recently extended Hawking's model by taking into account the quantum fluctuations of the geometry and the classical back-reaction of the emitted particles. Here, we calculate the train exerted on the falling stick for our model. The strain depends on the near-horizon state of the Hawking pairs. We find that, after the Page time when the state of the pairs deviates significantly from maximal entanglement (as required by unitarity), the induced strain in our semiclassical model is still parametrically small. This is because the number of the disentangled pairs is parametrically smaller than the BH entropy. A firewall does, however, appear if the number of disentangled pairs near the horizon is of order of the BH entropy, as implicitly assumed in previous discussions in the literature.

  19. Albeni Falls Wildlife Mitigation : Annual Report 2002.

    SciTech Connect

    Terra-Berns, Mary

    2003-01-01

    The Albeni Falls Interagency Work Group continued to actively engage in implementing wildlife mitigation actions in 2002. Regular Work Group meetings were held to discuss budget concerns affecting the Albeni Falls Wildlife Mitigation Program, to present potential acquisition projects, and to discuss and evaluate other issues affecting the Work Group and Project. Work Group members protected 1,386.29 acres of wildlife habitat in 2002. To date, the Albeni Falls project has protected approximately 5,914.31 acres of wildlife habitat. About 21% of the total wildlife habitat lost has been mitigated. Administrative activities have increased as more properties are purchased and continue to center on restoration, operation and maintenance, and monitoring. In 2001, Work Group members focused on development of a monitoring and evaluation program as well as completion of site-specific management plans. This year the Work Group began implementation of the monitoring and evaluation program performing population and plant surveys, data evaluation and storage, and map development as well as developing management plans. Assuming that the current BPA budget restrictions will be lifted in the near future, the Work Group expects to increase mitigation properties this coming year with several potential projects.

  20. Fall Down Detection Under Smart Home System.

    PubMed

    Juang, Li-Hong; Wu, Ming-Ni

    2015-10-01

    Medical technology makes an inevitable trend for the elderly population, therefore the intelligent home care is an important direction for science and technology development, in particular, elderly in-home safety management issues become more and more important. In this research, a low of operation algorithm and using the triangular pattern rule are proposed, then can quickly detect fall-down movements of humanoid by the installation of a robot with camera vision at home that will be able to judge the fall-down movements of in-home elderly people in real time. In this paper, it will present a preliminary design and experimental results of fall-down movements from body posture that utilizes image pre-processing and three triangular-mass-central points to extract the characteristics. The result shows that the proposed method would adopt some characteristic value and the accuracy can reach up to 90 % for a single character posture. Furthermore the accuracy can be up to 100 % when a continuous-time sampling criterion and support vector machine (SVM) classifier are used.