The timing of galvanic vestibular stimulation affects responses to platform translation

NASA Technical Reports Server (NTRS)

Hlavacka, F.; Shupert, C. L.; Horak, F. B.; Peterson, B. W. (Principal Investigator)

1999-01-01

We compared the effects of galvanic vestibular stimulation applied at 0, 0.5, 1.5 and 2.5 s prior to a backward platform translation on postural responses. The effect of the galvanic stimulation was largest on the final equilibrium position of the center of pressure (CoP). The largest effects occurred for the 0.5 and 0-s pre-period, when the dynamic CoP pressure changes in response to both the galvanic stimulus and the platform translation coincided. The shift in the final equilibrium position was also larger than the sum of the shifts for the galvanic stimulus and the platform translation alone for the 0.5 and 0-s pre-periods. The initial rate of change of the CoP response to the platform translation was not significantly affected in any condition. Changes in the peak CoP position could be accounted for by local interaction of CoP velocity changes induced by the galvanic and translation responses alone, but the changes in final equilibrium position could only be accounted for by a change in global body orientation. These findings suggest that the contribution of vestibulospinal information is greatest during the dynamic phase of the postural response, and that the vestibular system contributes most to the later components of the postural response, particularly to the final equilibrium position. These findings suggest that a nonlinear interaction between the vestibular signal induced by the galvanic current and the sensory stimuli produced by the platform translation occurs when the two stimuli are presented within 1 s, during the dynamic phase of the postural response to the galvanic stimulus. When presented at greater separations in time, the stimuli appear to be treated as independent events, such that no interaction occurs. Copyright 1999 Elsevier Science B.V.

Continental-scale consequences of tree die-offs in North America: identifying where forest loss matters most

NASA Astrophysics Data System (ADS)

Swann, Abigail L. S.; Laguë, Marysa M.; Garcia, Elizabeth S.; Field, Jason P.; Breshears, David D.; Moore, David J. P.; Saleska, Scott R.; Stark, Scott C.; Villegas, Juan Camilo; Law, Darin J.; Minor, David M.

2018-05-01

Regional-scale tree die-off events driven by drought and warming and associated pests and pathogens have occurred recently on all forested continents and are projected to increase in frequency and extent with future warming. Within areas where tree mortality has occurred, ecological, hydrological and meteorological consequences are increasingly being documented. However, the potential for tree die-off to impact vegetation processes and related carbon dynamics in areas remote to where die-off occurs has rarely been systematically evaluated, particularly for multiple distinct regions within a given continent. Such remote impacts can occur when climate effects of local vegetation change are propagated by atmospheric circulation—the phenomena of ‘ecoclimate teleconnections’. We simulated tree die-off events in the 13 most densely forested US regions (selected from the 20 US National Ecological Observatory Network [NEON] domains) and found that tree die-off even for smaller regions has potential to affect climate and hence Gross Primary Productivity (GPP) in disparate regions (NEON domains), either positively or negatively. Some regions exhibited strong teleconnections to several others, and some regions were relatively sensitive to tree loss regardless of what other region the tree loss occurred in. For the US as a whole, loss of trees in the Pacific Southwest—an area undergoing rapid tree die-off—had the largest negative impact on remote US GPP whereas loss of trees in the Mid-Atlantic had the largest positive impact. This research lays a foundation for hypotheses that identify how the effects of tree die-off (or other types of tree loss such as deforestation) can ricochet across regions by revealing hot-spots of forcing and response. Such modes of connectivity have direct applicability for improving models of climate change impacts and for developing more informed and coordinated carbon accounting across regions.

Cellulose nanocrystals the next big nano-thing?

Treesearch

Michael T. Postek; Andras Vladar; John Dagata; Natalia Farkas; Bin Ming; Ronald Sabo; Theodore H. Wegner; James Beecher

2008-01-01

Biomass surrounds us from the smallest alga to the largest redwood tree. Even the largest trees owe their strength to a newly-appreciated class of nanomaterials known as cellulose nanocrystals (CNC). Cellulose, the world’s most abundant natural, renewable, biodegradable polymer, occurs as whisker like microfibrils that are biosynthesized and deposited in plant material...

Nonlinear consolidation in randomly heterogeneous highly compressible aquitards

NASA Astrophysics Data System (ADS)

Zapata-Norberto, Berenice; Morales-Casique, Eric; Herrera, Graciela S.

2018-05-01

Severe land subsidence due to groundwater extraction may occur in multiaquifer systems where highly compressible aquitards are present. The highly compressible nature of the aquitards leads to nonlinear consolidation where the groundwater flow parameters are stress-dependent. The case is further complicated by the heterogeneity of the hydrogeologic and geotechnical properties of the aquitards. The effect of realistic vertical heterogeneity of hydrogeologic and geotechnical parameters on the consolidation of highly compressible aquitards is investigated by means of one-dimensional Monte Carlo numerical simulations where the lower boundary represents the effect of an instant drop in hydraulic head due to groundwater pumping. Two thousand realizations are generated for each of the following parameters: hydraulic conductivity ( K), compression index ( C c), void ratio ( e) and m (an empirical parameter relating hydraulic conductivity and void ratio). The correlation structure, the mean and the variance for each parameter were obtained from a literature review about field studies in the lacustrine sediments of Mexico City. The results indicate that among the parameters considered, random K has the largest effect on the ensemble average behavior of the system when compared to a nonlinear consolidation model with deterministic initial parameters. The deterministic solution underestimates the ensemble average of total settlement when initial K is random. In addition, random K leads to the largest variance (and therefore largest uncertainty) of total settlement, groundwater flux and time to reach steady-state conditions.

Peak discharge of a Pleistocene lava-dam outburst flood in Grand Canyon, Arizona, USA

USGS Publications Warehouse

Fenton, C.R.; Webb, R.H.; Cerling, T.E.

2006-01-01

The failure of a lava dam 165,000 yr ago produced the largest known flood on the Colorado River in Grand Canyon. The Hyaloclastite Dam was up to 366 m high, and geochemical evidence linked this structure to outburst-flood deposits that occurred for 32 km downstream. Using the Hyaloclastite outburst-flood deposits as paleostage indicators, we used dam-failure and unsteady flow modeling to estimate a peak discharge and flow hydrograph. Failure of the Hyaloclastite Dam released a maximum 11 ?? 109 m3 of water in 31 h. Peak discharges, estimated from uncertainty in channel geometry, dam height, and hydraulic characteristics, ranged from 2.3 to 5.3 ?? 105 m3 s-1 for the Hyaloclastite outburst flood. This discharge is an order of magnitude greater than the largest known discharge on the Colorado River (1.4 ?? 104 m3 s-1) and the largest peak discharge resulting from failure of a constructed dam in the USA (6.5 ?? 104 m3 s-1). Moreover, the Hyaloclastite outburst flood is the oldest documented Quaternary flood and one of the largest to have occurred in the continental USA. The peak discharge for this flood ranks in the top 30 floods (>105 m3 s-1) known worldwide and in the top ten largest floods in North America. ?? 2005 University of Washington. All rights reserved.

Peak discharge of a Pleistocene lava-dam outburst flood in Grand Canyon, Arizona, USA

NASA Astrophysics Data System (ADS)

Fenton, Cassandra R.; Webb, Robert H.; Cerling, Thure E.

2006-03-01

The failure of a lava dam 165,000 yr ago produced the largest known flood on the Colorado River in Grand Canyon. The Hyaloclastite Dam was up to 366 m high, and geochemical evidence linked this structure to outburst-flood deposits that occurred for 32 km downstream. Using the Hyaloclastite outburst-flood deposits as paleostage indicators, we used dam-failure and unsteady flow modeling to estimate a peak discharge and flow hydrograph. Failure of the Hyaloclastite Dam released a maximum 11 × 10 9 m 3 of water in 31 h. Peak discharges, estimated from uncertainty in channel geometry, dam height, and hydraulic characteristics, ranged from 2.3 to 5.3 × 10 5 m 3 s -1 for the Hyaloclastite outburst flood. This discharge is an order of magnitude greater than the largest known discharge on the Colorado River (1.4 × 10 4 m 3 s -1) and the largest peak discharge resulting from failure of a constructed dam in the USA (6.5 × 10 4 m 3 s -1). Moreover, the Hyaloclastite outburst flood is the oldest documented Quaternary flood and one of the largest to have occurred in the continental USA. The peak discharge for this flood ranks in the top 30 floods (>10 5 m 3 s -1) known worldwide and in the top ten largest floods in North America.

Comparative effectiveness and cost-effectiveness analyses frequently agree on value.

PubMed

Glick, Henry A; McElligott, Sean; Pauly, Mark V; Willke, Richard J; Bergquist, Henry; Doshi, Jalpa; Fleisher, Lee A; Kinosian, Bruce; Perfetto, Eleanor; Polsky, Daniel E; Schwartz, J Sanford

2015-05-01

The Patient-Centered Outcomes Research Institute, known as PCORI, was established by Congress as part of the Affordable Care Act (ACA) to promote evidence-based treatment. Provisions of the ACA prohibit the use of a cost-effectiveness analysis threshold and quality-adjusted life-years (QALYs) in PCORI comparative effectiveness studies, which has been understood as a prohibition on support for PCORI's conducting conventional cost-effectiveness analyses. This constraint complicates evidence-based choices where incremental improvements in outcomes are achieved at increased costs of care. How frequently this limitation inhibits efficient cost containment, also a goal of the ACA, depends on how often more effective treatment is not cost-effective relative to less effective treatment. We examined the largest database of studies of comparisons of effectiveness and cost-effectiveness to see how often there is disagreement between the more effective treatment and the cost-effective treatment, for various thresholds that may define good value. We found that under the benchmark assumption, disagreement between the two types of analyses occurs in 19 percent of cases. Disagreement is more likely to occur if a treatment intervention is musculoskeletal and less likely to occur if it is surgical or involves secondary prevention, or if the study was funded by a pharmaceutical company. Project HOPE—The People-to-People Health Foundation, Inc.

Time scales involved in emergent market coherence

NASA Astrophysics Data System (ADS)

Kwapień, J.; Drożdż, S.; Speth, J.

2004-06-01

In addressing the question of the time scales characteristic for the market formation, we analyze high-frequency tick-by-tick data from the NYSE and from the German market. By using returns on various time scales ranging from seconds or minutes up to 2 days, we compare magnitude of the largest eigenvalue of the correlation matrix for the same set of securities but for different time scales. For various sets of stocks of different capitalization (and the average trading frequency), we observe a significant elevation of the largest eigenvalue with increasing time scale. Our results from the correlation matrix study can be considered as a manifestation of the so-called Epps effect. There is no unique explanation of this effect and it seems that many different factors play a role here. One of such factors is randomness in transaction moments for different stocks. Another interesting conclusion to be drawn from our results is that in the contemporary markets the emergence of significant correlations occurs on time scales much smaller than in the more distant history.

The melting Himalayas: cascading effects of climate change on water, biodiversity, and livelihoods.

PubMed

Xu, Jianchu; Grumbine, R Edward; Shrestha, Arun; Eriksson, Mats; Yang, Xuefei; Wang, Yun; Wilkes, Andreas

2009-06-01

The Greater Himalayas hold the largest mass of ice outside polar regions and are the source of the 10 largest rivers in Asia. Rapid reduction in the volume of Himalayan glaciers due to climate change is occurring. The cascading effects of rising temperatures and loss of ice and snow in the region are affecting, for example, water availability (amounts, seasonality), biodiversity (endemic species, predator-prey relations), ecosystem boundary shifts (tree-line movements, high-elevation ecosystem changes), and global feedbacks (monsoonal shifts, loss of soil carbon). Climate change will also have environmental and social impacts that will likely increase uncertainty in water supplies and agricultural production for human populations across Asia. A common understanding of climate change needs to be developed through regional and local-scale research so that mitigation and adaptation strategies can be identified and implemented. The challenges brought about by climate change in the Greater Himalayas can only be addressed through increased regional collaboration in scientific research and policy making. ©2009 Society for Conservation Biology.

The Cataclysmic 1991 Eruption of Mount Pinatubo, Philippines

USGS Publications Warehouse

Newhall, Christopher G.; Hendley, James W.; Stauffer, Peter H.

1997-01-01

The second-largest volcanic eruption of this century, and by far the largest eruption to affect a densely populated area, occurred at Mount Pinatubo in the Philippines on June 15, 1991. The eruption produced high-speed avalanches of hot ash and gas, giant mudflows, and a cloud of volcanic ash hundreds of miles across. The impacts of the eruption continue to this day.

Environmental Assessment for the Replacement of Water Reservoirs

DTIC Science & Technology

2005-03-25

Intensive extraction of groundwater does not occur at Travis because of poor water- bearing subsurface geology. Intensive extraction SECTION 3.0...largest contiguous estuarine marsh and the largest wetland in the continental United States (CH2M HILL, 2001). Suisun Marsh drains into Grizzly and...and other support facilities. • Community (Commercial) – Uses include the exchange, commissary, banking, dining facilities, eating

Observational evidence for turbulent effects on total suspended matter within the Pearl River plume

NASA Astrophysics Data System (ADS)

Chunhua, Qiu; Danyi, Su; Huabin, Mao; Jiaxue, Wu; Yongsheng, Cui; Dongxiao, Wang

2017-12-01

We observed the structure of the Pearl River plume and its turbulent characteristics, and investigated the turbulent effect on total suspended matter (TSM) within its ;far-field; region, based on in situ and satellite data collected in June 2015. A significant northeastward plume was created under southern monsoonal conditions. The in situ data provided the width, depth, and velocity of the plume, as inferred by salinity. Weaker turbulence occurred at the front surface position than in the plume zone. Stronger turbulence induced greater turbidity in the bottom boundary layer; however, the surface mixed layer differed. By estimating the turbidity budget, we found the lateral fluxes term was the largest term in the plume, turbulent fluxes comprised the second largest term, and the settling terms comprised the smallest term. We quantified the turbulent mechanisms and found that stronger river discharge induced greater TSM turbidity. Tidal and buoyancy fluxes had minor regulatory effects on TSM. Our observations suggest that TSM in the ;far field; region originated from the Pearl River and the coastal region.

Differential effects of dietary diversity and maternal characteristics on linear growth of children aged 6-59 months in sub-Saharan Africa: a multi-country analysis.

PubMed

Amugsi, Dickson A; Dimbuene, Zacharie T; Kimani-Murage, Elizabeth W; Mberu, Blessing; Ezeh, Alex C

2017-04-01

To investigate the differential effects of dietary diversity (DD) and maternal characteristics on child linear growth at different points of the conditional distribution of height-for-age Z-score (HAZ) in sub-Saharan Africa. Secondary analysis of data from nationally representative cross-sectional samples of singleton children aged 0-59 months, born to mothers aged 15-49 years. The outcome variable was child HAZ. Quantile regression was used to perform the multivariate analysis. The most recent Demographic and Health Surveys from Ghana, Nigeria, Kenya, Mozambique and Democratic Republic of Congo (DRC). The present analysis was restricted to children aged 6-59 months (n 31 604). DD was associated positively with HAZ in the first four quantiles (5th, 10th, 25th and 50th) and the highest quantile (90th) in Nigeria. The largest effect occurred at the very bottom (5th quantile) and the very top (90th quantile) of the conditional HAZ distribution. In DRC, DD was significantly and positively associated with HAZ in the two lower quantiles (5th, 10th). The largest effects of maternal education occurred at the lower end of the conditional HAZ distribution in Ghana, Nigeria and DRC. Maternal BMI and height also had positive effects on HAZ at different points of the conditional distribution of HAZ. Our analysis shows that the association between DD and maternal factors and HAZ differs along the conditional HAZ distribution. Intervention measures need to take into account the heterogeneous effect of the determinants of child nutritional status along the different percentiles of the HAZ distribution.

The geomorphic effectiveness of a large flood on the Rio Grande in the Big Bend region: insights on geomorphic controls and post-flood geomorphic response

USGS Publications Warehouse

Dean, David J.; Schmidt, John C.

2013-01-01

Since the 1940s, the Rio Grande in the Big Bend region has undergone long periods of channel narrowing, which have been occasionally interrupted by rare, large floods that widen the channel (termed a channel reset). The most recent channel reset occurred in 2008 following a 17-year period of extremely low stream flow and rapid channel narrowing. Flooding was caused by precipitation associated with the remnants of tropical depression Lowell in the Rio Conchos watershed, the largest tributary to the Rio Grande. Floodwaters approached 1500 m3/s (between a 13 and 15 year recurrence interval) and breached levees, inundated communities, and flooded the alluvial valley of the Rio Grande; the wetted width exceeding 2.5 km in some locations. The 2008 flood had the 7th largest magnitude of record, however, conveyed the largest volume of water than any other flood. Because of the narrow pre-flood channel conditions, record flood stages occurred. We used pre- and post-flood aerial photographs, channel and floodplain surveys, and 1-dimensional hydraulic models to quantify the magnitude of channel change, investigate the controls of flood-induced geomorphic changes, and measure the post-flood response of the widened channel. These analyses show that geomorphic changes included channel widening, meander migration, avulsions, extensive bar formation, and vertical floodplain accretion. Reach-averaged channel widening between 26 and 52% occurred, but in some localities exceeded 500%. The degree and style of channel response was related, but not limited to, three factors: 1) bed-load supply and transport, 2) pre-flood channel plan form, and 3) rapid declines in specific stream power downstream of constrictions and areas of high channel bed slope. The post-flood channel response has consisted of channel contraction through the aggradation of the channel bed and the formation of fine-grained benches inset within the widened channel margins. The most significant post-flood geomorphic changes have occurred at and downstream from ephemeral tributaries that contribute large volumes of sediment.

Attribution of CO2 emissions from Brazilian deforestation to domestic and international drivers

NASA Astrophysics Data System (ADS)

Karstensen, J.; Peters, G.

2011-12-01

Efforts to address extensive deforestation to reduce climate change and save primary forests are taking place on a global scale. Whilst several studies have estimated the emissions occurring from deforestation in large rainforests, few studies have investigated the domestic and international drivers sustaining and increasing the deforestation rates. Brazil, having the largest rainforest in the world and one of the highest deforestation rates, is also currently one of the world's largest exporters of soybeans and beef. In this case study we establish the link between Brazilian deforestation and cattle and soybean production, and further attribute emissions to countries and economic sectors through export and import of Brazilian commodities. The emissions from deforestation can therefore be allocated to the countries and sectors consuming goods and services produced on deforested land in Brazil. A land-use change model and deforestation data is coupled with a carbon cycle model to create yearly emission estimates and different emission allocation schemes, depending on emission amortizations and discounting functions for past deforestation. We use an economic multi-regional input-output model (with 112 regions and 57 sectors) to distribute these emissions along agricultural trade routes, through domestic and international consumption in 2004. With our implementation we find that around 80 % of emissions from deforested land is due to cattle grazing, while agricultural transition effects suggests soy beans are responsible for about 20 % of the emissions occurring in 2004. Nearly tree quarters of the soy beans are consumed outside Brazil, of which China, Germany and France are the biggest consumers. Soy beans are consumed by a variety of sectors in the food industry. Brazil exports about 30 % of the cattle it produces, where Russia, USA and Germany are among the largest consumers. Cattle consumption mainly occurs in the meat sectors. In this study we estimate the CO2 emissions allocated to the consuming countries and economic sectors, to ultimately distribute responsibility and find the main drivers of Brazilian deforestation.

A catalog of aftershock sequences in Greece (1971 1997): Their spatial and temporal characteristics

NASA Astrophysics Data System (ADS)

Drakatos, George; Latoussakis, John

A complete catalog of aftershock sequences is provided for main earthquakes with ML 5.0, which occurred in the area of Greece and surrounding regions the last twenty-seven years. The Monthly Bulletins of the Institute of Geodynamics (National Observatory of Athens) have been used as data source. In order to get a homogeneous catalog, several selection criteria have been applied and hence a catalog of 44 aftershock sequences is compiled. The relations between the duration of the sequence, the number of aftershocks, the magnitude of the largest aftershock and its delay time from the main shock as well as the subsurface rupture length versus the magnitude of the main shock are calculated. The results show that linearity exists between the subsurface rupture length and the magnitude of the main shock independent of the slip type, as well as between the magnitude of the main shock (M) and its largest aftershock (Ma). The mean difference M-Ma is almost one unit. In the 40% of the analyzed sequences, the largest aftershock occurred within one day after the main shock.The fact that the aftershock sequences show the same behavior for earthquakes that occur in the same region supports the theory that the spatial and temporal characteristics are strongly related to the stress distribution of the fault area.

The impact of Global Warming on global crop yields due to changes in pest pressure

NASA Astrophysics Data System (ADS)

Battisti, D. S.; Tewksbury, J. J.; Deutsch, C. A.

2011-12-01

A billion people currently lack reliable access to sufficient food and almost half of the calories feeding these people come from just three crops: rice, maize, wheat. Insect pests are among the largest factors affecting the yield of these three crops, but models assessing the effects of global warming on crops rarely consider changes in insect pest pressure on crop yields. We use well-established relationships between temperature and insect physiology to project climate-driven changes in pest pressure, defined as integrated population metabolism, for the three major crops. By the middle of this century, under most scenarios, insect pest pressure is projected to increase by more than 50% in temperate areas, while increases in tropical regions will be more modest. Yield relationships indicate that the largest increases in insect pest pressure are likely to occur in areas where yield is greatest, suggesting increased strain on global food markets.

Young Adult Women and the Pilgrimage of Motherhood

ERIC Educational Resources Information Center

Lipperini, Patricia T.

2016-01-01

Motherhood is a complex experience that can be transformative, offering women opportunities for personal enrichment and spiritual development. Because the largest incidence of births occurs to women in the Millennial or late Generation X generations, this complex, potentially transformative experience occurs at a critical time in young adult…

Oklahoma experiences largest earthquake during ongoing regional wastewater injection hazard mitigation efforts

USGS Publications Warehouse

Yeck, William; Hayes, Gavin; McNamara, Daniel E.; Rubinstein, Justin L.; Barnhart, William; Earle, Paul; Benz, Harley M.

2017-01-01

The 3 September 2016, Mw 5.8 Pawnee earthquake was the largest recorded earthquake in the state of Oklahoma. Seismic and geodetic observations of the Pawnee sequence, including precise hypocenter locations and moment tensor modeling, shows that the Pawnee earthquake occurred on a previously unknown left-lateral strike-slip basement fault that intersects the mapped right-lateral Labette fault zone. The Pawnee earthquake is part of an unprecedented increase in the earthquake rate in Oklahoma that is largely considered the result of the deep injection of waste fluids from oil and gas production. If this is, indeed, the case for the M5.8 Pawnee earthquake, then this would be the largest event to have been induced by fluid injection. Since 2015, Oklahoma has undergone wide-scale mitigation efforts primarily aimed at reducing injection volumes. Thus far in 2016, the rate of M3 and greater earthquakes has decreased as compared to 2015, while the cumulative moment—or energy released from earthquakes—has increased. This highlights the difficulty in earthquake hazard mitigation efforts given the poorly understood long-term diffusive effects of wastewater injection and their connection to seismicity.

The U.S. Financial Crisis: The Global Dimension With Implications for U.S. Policy

DTIC Science & Technology

2008-11-18

financial crisis. Some of the largest and most venerable banks, investment houses, and insurance companies have either declared bankruptcy or have had to...of the largest and most venerable banks, investment houses, and insurance companies have either declared bankruptcy or have had to be rescued...and inadequate capital backing credit default swaps ( insurance against defaults and bankruptcy) have occurred. The second level of the crisis is

Small-scale martian polygonal terrain: Implications for liquid surface water

USGS Publications Warehouse

Seibert, N.M.; Kargel, J.S.

2001-01-01

Images from the Mars Orbiter Camera (MOC) through August 1999 were analyzed for the global distribution of small-scale polygonal terrain not clearly resolved in Viking Orbiter imagery. With very few exceptions, small-scale polygonal terrain occurs at middle to high latitudes of the northern and southern hemisphere in Hesperian-age geologic units. The largest concentration of this terrain occurs in the Utopia basin in close association with scalloped depressions (interpreted as thermokarst) and appears to represent an Amazonia event. The morphology and occurence of small polygonal terrain suggest they are either mud desiccation cracks or ice-wedge polygons. Because the small-scale polygons in Utopia and Argyre Planitiae are associated with other cold-climate permafrost or glacial features, an ice-wedge model is preferred for these areas. Both cracking mechanisms work most effectively in water- or ice-rich finegrained material and may imply the seasonal or episodic existence of liquid water at the surface.

Stable creeping fault segments can become destructive as a result of dynamic weakening.

PubMed

Noda, Hiroyuki; Lapusta, Nadia

2013-01-24

Faults in Earth's crust accommodate slow relative motion between tectonic plates through either similarly slow slip or fast, seismic-wave-producing rupture events perceived as earthquakes. These types of behaviour are often assumed to be separated in space and to occur on two different types of fault segment: one with stable, rate-strengthening friction and the other with rate-weakening friction that leads to stick-slip. The 2011 Tohoku-Oki earthquake with moment magnitude M(w) = 9.0 challenged such assumptions by accumulating its largest seismic slip in the area that had been assumed to be creeping. Here we propose a model in which stable, rate-strengthening behaviour at low slip rates is combined with coseismic weakening due to rapid shear heating of pore fluids, allowing unstable slip to occur in segments that can creep between events. The model parameters are based on laboratory measurements on samples from the fault of the M(w) 7.6 1999 Chi-Chi earthquake. The long-term slip behaviour of the model, which we examine using a unique numerical approach that includes all wave effects, reproduces and explains a number of both long-term and coseismic observations-some of them seemingly contradictory-about the faults at which the Tohoku-Oki and Chi-Chi earthquakes occurred, including there being more high-frequency radiation from areas of lower slip, the largest seismic slip in the Tohoku-Oki earthquake having occurred in a potentially creeping segment, the overall pattern of previous events in the area and the complexity of the Tohoku-Oki rupture. The implication that earthquake rupture may break through large portions of creeping segments, which are at present considered to be barriers, requires a re-evaluation of seismic hazard in many areas.

Stable Carbon Fractionation In Size Segregated Aerosol Particles Produced By Controlled Biomass Burning

NASA Astrophysics Data System (ADS)

Masalaite, Agne; Garbaras, Andrius; Garbariene, Inga; Ceburnis, Darius; Martuzevicius, Dainius; Puida, Egidijus; Kvietkus, Kestutis; Remeikis, Vidmantas

2014-05-01

Biomass burning is the largest source of primary fine fraction carbonaceous particles and the second largest source of trace gases in the global atmosphere with a strong effect not only on the regional scale but also in areas distant from the source . Many studies have often assumed no significant carbon isotope fractionation occurring between black carbon and the original vegetation during combustion. However, other studies suggested that stable carbon isotope ratios of char or BC may not reliably reflect carbon isotopic signatures of the source vegetation. Overall, the apparently conflicting results throughout the literature regarding the observed fractionation suggest that combustion conditions may be responsible for the observed effects. The purpose of the present study was to gather more quantitative information on carbonaceous aerosols produced in controlled biomass burning, thereby having a potential impact on interpreting ambient atmospheric observations. Seven different biomass fuel types were burned under controlled conditions to determine the effect of the biomass type on the emitted particulate matter mass and stable carbon isotope composition of bulk and size segregated particles. Size segregated aerosol particles were collected using the total suspended particle (TSP) sampler and a micro-orifice uniform deposit impactor (MOUDI). The results demonstrated that particle emissions were dominated by the submicron particles in all biomass types. However, significant differences in emissions of submicron particles and their dominant sizes were found between different biomass fuels. The largest negative fractionation was obtained for the wood pellet fuel type while the largest positive isotopic fractionation was observed during the buckwheat shells combustion. The carbon isotope composition of MOUDI samples compared very well with isotope composition of TSP samples indicating consistency of the results. The measurements of the stable carbon isotope ratio in size segregated aerosol particles suggested that combustion processes could strongly affect isotopic fractionation in aerosol particles of different sizes thereby potentially affecting an interpretation of ambient atmospheric observations.

AcuteToxicological Responses of Fischer Rats to Naturally Occurring Asbestos Samples from the United States and Canada

EPA Science Inventory

The potential public health issues related to exposure to natural asbestos deposits (commonly termed naturally occurring asbestos, NO A) has gained the regulatory and media spotlight in recent years. Arguably the most well known example is Libby, Montana, the site of the largest ...

Earthquakes, September-October 1978

USGS Publications Warehouse

Person, W.J.

1979-01-01

The months of September and October were somewhat quiet seismically speaking. One major earthquake, magnitude (M) 7.7 occurred in Iran on September 16. In Germany, a magntidue 5.0 earthquake caused damage and considerable alarm to many people in parts of that country. In the United States, the largest earthquake occurred along the California-Nevada border region. 

A synthesis of methane emissions from 71 northern, temperate, and subtropical wetlands.

PubMed

Turetsky, Merritt R; Kotowska, Agnieszka; Bubier, Jill; Dise, Nancy B; Crill, Patrick; Hornibrook, Ed R C; Minkkinen, Kari; Moore, Tim R; Myers-Smith, Isla H; Nykänen, Hannu; Olefeldt, David; Rinne, Janne; Saarnio, Sanna; Shurpali, Narasinha; Tuittila, Eeva-Stiina; Waddington, J Michael; White, Jeffrey R; Wickland, Kimberly P; Wilmking, Martin

2014-07-01

Wetlands are the largest natural source of atmospheric methane. Here, we assess controls on methane flux using a database of approximately 19 000 instantaneous measurements from 71 wetland sites located across subtropical, temperate, and northern high latitude regions. Our analyses confirm general controls on wetland methane emissions from soil temperature, water table, and vegetation, but also show that these relationships are modified depending on wetland type (bog, fen, or swamp), region (subarctic to temperate), and disturbance. Fen methane flux was more sensitive to vegetation and less sensitive to temperature than bog or swamp fluxes. The optimal water table for methane flux was consistently below the peat surface in bogs, close to the peat surface in poor fens, and above the peat surface in rich fens. However, the largest flux in bogs occurred when dry 30-day averaged antecedent conditions were followed by wet conditions, while in fens and swamps, the largest flux occurred when both 30-day averaged antecedent and current conditions were wet. Drained wetlands exhibited distinct characteristics, e.g. the absence of large flux following wet and warm conditions, suggesting that the same functional relationships between methane flux and environmental conditions cannot be used across pristine and disturbed wetlands. Together, our results suggest that water table and temperature are dominant controls on methane flux in pristine bogs and swamps, while other processes, such as vascular transport in pristine fens, have the potential to partially override the effect of these controls in other wetland types. Because wetland types vary in methane emissions and have distinct controls, these ecosystems need to be considered separately to yield reliable estimates of global wetland methane release. © 2014 John Wiley & Sons Ltd.

A synthesis of methane emissions from 71 northern, temperate, and subtropical wetlands

USGS Publications Warehouse

Turetsky, Merritt R.; Kotowska, Agnieszka; Bubier, Jill; Dise, Nancy B.; Crill, Patrick; Hornibrook, Ed R.C.; Minkkinen, Kari; Moore, Tim R.; Myers-Smith, Isla H.; Nykanen, Hannu; Olefeldt, David; Rinne, Janne; Saarnio, Sanna; Shurpali, Narasinha; Tuittila, Eeva-Stiina; Waddington, J. Michael; White, Jeffrey R.; Wickland, Kimberly P.; Wilmking, Martin

2014-01-01

Wetlands are the largest natural source of atmospheric methane. Here, we assess controls on methane flux using a database of approximately 19 000 instantaneous measurements from 71 wetland sites located across subtropical, temperate, and northern high latitude regions. Our analyses confirm general controls on wetland methane emissions from soil temperature, water table, and vegetation, but also show that these relationships are modified depending on wetland type (bog, fen, or swamp), region (subarctic to temperate), and disturbance. Fen methane flux was more sensitive to vegetation and less sensitive to temperature than bog or swamp fluxes. The optimal water table for methane flux was consistently below the peat surface in bogs, close to the peat surface in poor fens, and above the peat surface in rich fens. However, the largest flux in bogs occurred when dry 30-day averaged antecedent conditions were followed by wet conditions, while in fens and swamps, the largest flux occurred when both 30-day averaged antecedent and current conditions were wet. Drained wetlands exhibited distinct characteristics, e.g. the absence of large flux following wet and warm conditions, suggesting that the same functional relationships between methane flux and environmental conditions cannot be used across pristine and disturbed wetlands. Together, our results suggest that water table and temperature are dominant controls on methane flux in pristine bogs and swamps, while other processes, such as vascular transport in pristine fens, have the potential to partially override the effect of these controls in other wetland types. Because wetland types vary in methane emissions and have distinct controls, these ecosystems need to be considered separately to yield reliable estimates of global wetland methane release.

The joint use of the tangential electric field and surface Laplacian in EEG classification.

PubMed

Carvalhaes, C G; de Barros, J Acacio; Perreau-Guimaraes, M; Suppes, P

2014-01-01

We investigate the joint use of the tangential electric field (EF) and the surface Laplacian (SL) derivation as a method to improve the classification of EEG signals. We considered five classification tasks to test the validity of such approach. In all five tasks, the joint use of the components of the EF and the SL outperformed the scalar potential. The smallest effect occurred in the classification of a mental task, wherein the average classification rate was improved by 0.5 standard deviations. The largest effect was obtained in the classification of visual stimuli and corresponded to an improvement of 2.1 standard deviations.

Listening to the 2011 magnitude 9.0 Tohoku-Oki, Japan, earthquake

USGS Publications Warehouse

Peng, Zhigang; Aiken, Chastity; Kilb, Debi; Shelly, David R.; Enescu, Bogdan

2012-01-01

The magnitude 9.0 Tohoku-Oki, Japan, earthquake on 11 March 2011 is the largest earthquake to date in Japan’s modern history and is ranked as the fourth largest earthquake in the world since 1900. This earthquake occurred within the northeast Japan subduction zone (Figure 1), where the Pacific plate is subducting beneath the Okhotsk plate at rate of ∼8–9 cm/yr (DeMets et al. 2010). This type of extremely large earthquake within a subduction zone is generally termed a “megathrust” earthquake. Strong shaking from this magnitude 9 earthquake engulfed the entire Japanese Islands, reaching a maximum acceleration ∼3 times that of gravity (3 g). Two days prior to the main event, a foreshock sequence occurred, including one earthquake of magnitude 7.2. Following the main event, numerous aftershocks occurred around the main slip region; the largest of these was magnitude 7.9. The entire foreshocks-mainshock-aftershocks sequence was well recorded by thousands of sensitive seismometers and geodetic instruments across Japan, resulting in the best-recorded megathrust earthquake in history. This devastating earthquake resulted in significant damage and high death tolls caused primarily by the associated large tsunami. This tsunami reached heights of more than 30 m, and inundation propagated inland more than 5 km from the Pacific coast, which also caused a nuclear crisis that is still affecting people’s lives in certain regions of Japan.

Safe drinking water and waterborne outbreaks.

PubMed

Moreira, N A; Bondelind, M

2017-02-01

The present work compiles a review on drinking waterborne outbreaks, with the perspective of production and distribution of microbiologically safe water, during 2000-2014. The outbreaks are categorised in raw water contamination, treatment deficiencies and distribution network failure. The main causes for contamination were: for groundwater, intrusion of animal faeces or wastewater due to heavy rain; in surface water, discharge of wastewater into the water source and increased turbidity and colour; at treatment plants, malfunctioning of the disinfection equipment; and for distribution systems, cross-connections, pipe breaks and wastewater intrusion into the network. Pathogens causing the largest number of affected consumers were Cryptosporidium, norovirus, Giardia, Campylobacter, and rotavirus. The largest number of different pathogens was found for the treatment works and the distribution network. The largest number of affected consumers with gastrointestinal illness was for contamination events from a surface water source, while the largest number of individual events occurred for the distribution network.

Track structure model for damage to mammalian cell cultures during solar proton events

NASA Technical Reports Server (NTRS)

Cucinotta, F. A.; Wilson, J. W.; Townsend, L. W.; Shinn, J. L.; Katz, R.

1992-01-01

Solar proton events (SPEs) occur infrequently and unpredictably, thus representing a potential hazard to interplanetary space missions. Biological damage from SPEs will be produced principally through secondary electron production in tissue, including important contributions due to delta rays from nuclear reaction products. We review methods for estimating the biological effectiveness of SPEs using a high energy proton model and the parametric cellular track model. Results of the model are presented for several of the historically largest flares using typical levels and body shielding.

Fault Rupture Model of the 2016 Gyeongju, South Korea, Earthquake and Its Implication for the Underground Fault System

NASA Astrophysics Data System (ADS)

Uchide, Takahiko; Song, Seok Goo

2018-03-01

The 2016 Gyeongju earthquake (ML 5.8) was the largest instrumentally recorded inland event in South Korea. It occurred in the southeast of the Korean Peninsula and was preceded by a large ML 5.1 foreshock. The aftershock seismicity data indicate that these earthquakes occurred on two closely collocated parallel faults that are oblique to the surface trace of the Yangsan fault. We investigate the rupture properties of these earthquakes using finite-fault slip inversion analyses. The obtained models indicate that the ruptures propagated NNE-ward and SSW-ward for the main shock and the large foreshock, respectively. This indicates that these earthquakes occurred on right-step faults and were initiated around a fault jog. The stress drops were up to 62 and 43 MPa for the main shock and the largest foreshock, respectively. These high stress drops imply high strength excess, which may be overcome by the stress concentration around the fault jog.

Patterns of growth dominance in thinned yellow-poplar stands in the southern Appalachian Mountains, USA

Treesearch

Tara L. Keyser

2012-01-01

Growth dominance provides a quantitative description of the relative contribution of individual trees to stand growth. Positive dominance occurs when the largest individuals account for a greater proportion of growth period increment than total biomass. Conversely, negative dominance occurs when the smallest trees account for a greater proportion of the growth period...

IMPROVIDING SUSTAINABILITY IN METALLIC MATERIALS THROUGH REDUCTION OF WASTES DISCARDED TO THE ENVIRONMENT BY RECOVERY AND REUSE IN EXTRACTION AND FABRICATION INDUSTRIES

EPA Science Inventory

Designed to chronicle the pollution problem occurring at one of the world's largest Superfund sites and to address the potential of the application of the approach of the recovery of metal resources occurring in the acid mine drainage causing the pollution problem. Acid mine drai...

Decreased diversion by doctor-shopping for a reformulated extended release oxycodone product (OxyContin).

PubMed

Chilcoat, Howard D; Coplan, Paul M; Harikrishnan, Venkatesh; Alexander, Louis

2016-08-01

Doctor-shopping (obtaining prescriptions from multiple prescribers/pharmacies) for opioid analgesics produces a supply for diversion and abuse, and represents a major public health issue. An open cohort study assessed changes in doctor-shopping in the U.S. for a brand extended release (ER) oxycodone product (OxyContin) and comparator opioids before (July, 2009 to June, 2010) versus after (January, 2011 to June, 2013) introduction of reformulated brand ER oxycodone with abuse-deterrent properties, using IMS LRx longitudinal data covering >150 million patients and 65% of retail U.S. prescriptions. After its reformulation, the rate of doctor-shopping decreased 50% (for 2+ prescribers/3+ pharmacies) for brand ER oxycodone, but not for comparators. The largest decreases in rates occurred among young adults (73%), those paying with cash (61%) and those receiving the highest available dose (62%), with a 90% decrease when stratifying by all three characteristics. The magnitude of doctor-shopping reductions increased with increasing number of prescribers/pharmacies (e.g., 75% reduction for ≥2 prescribers/≥4 pharmacies). The rate of doctor-shopping for brand ER oxycodone decreased substantially after its reformulation, which did not occur for other prescription opioids. The largest reductions in doctor-shopping occurred with characteristics associated with higher abuse risk such as youth, cash payment and high dose, and with more specific thresholds of doctor-shopping. A higher prescriber and/or pharmacy threshold also increased the magnitude of the decrease, suggesting that it better captured the effect of the reformulation on actual doctor-shoppers. Copyright © 2016 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

Induced Earthquakes Are Not All Alike: Examples from Texas Since 2008 (Invited)

NASA Astrophysics Data System (ADS)

Frohlich, C.

2013-12-01

The EarthScope Transportable Array passed through Texas between 2008 and 2011, providing an opportunity to identify and accurately locate earthquakes near and/or within oil/gas fields and injection waste disposal operations. In five widely separated geographical locations, the results suggest seismic activity may be induced/triggered. However, the different regions exhibit different relationships between injection/production operations and seismic activity: In the Barnett Shale of northeast Texas, small earthquakes occurred only near higher-volume (volume rate > 150,000 BWPM) injection disposal wells. These included widely reported earthquakes occurring near Dallas-Fort Worth and Cleburne in 2008 and 2009. Near Alice in south Texas, M3.9 earthquakes occurred in 1997 and 2010 on the boundary of the Stratton Field, which had been highly productive for both oil and gas since the 1950's. Both earthquakes occurred during an era of net declining production, but their focal depths and location at the field boundary suggest an association with production activity. In the Eagle Ford of south central Texas, earthquakes occurred near wells following significant increases in extraction (water+produced oil) volumes as well as injection. The largest earthquake, the M4.8 Fashing earthquake of 20 October 2011, occurred after significant increases in extraction. In the Cogdell Field near Snyder (west Texas), a sequence of earthquakes beginning in 2006 followed significant increases in the injection of CO2 at nearby wells. The largest with M4.4 occurred on 11 September 2011. This is the largest known earthquake possibly attributable to CO2 injection. Near Timpson in east Texas a sequence of earthquakes beginning in 2008, including an M4.8 earthquake on 17 May 2012, occurred within three km of two high-volume injection disposal wells that had begun operation in 2007. These were the first known earthquakes at this location. In summary, the observations find possible induced/triggered earthquakes associated with recent increases in injection, recent increases in extraction, with CO2 injection, and with declining production. In all areas, during the 2008-2011 period there were no earthquakes occurring near vast majority of extraction/production wells; thus, the principal puzzle is why these activities sometimes induce seismicity and sometimes do not.

Initial Breakdown Pulse Parameters in Intracloud and Cloud-to-Ground Lightning Flashes

NASA Astrophysics Data System (ADS)

Smith, E. M.; Marshall, T. C.; Karunarathne, S.; Siedlecki, R.; Stolzenburg, M.

2018-02-01

This study analyzes the largest initial breakdown (IB) pulse in flashes from four storms in Florida; data from three sensor arrays are used. The range-normalized, zero-to-peak amplitude of the largest IB pulse was determined along with its altitude, duration, and timing within each flash. Appropriate data were available for 40 intracloud (IC) and 32 cloud-to-ground (CG) flashes. Histograms of amplitude of the largest IB pulse by flash type were similar, with mean (median) values of 1.49 (1.05) V/m for IC flashes and -1.35 (-0.87) V/m for CG flashes. The largest IB pulse in 30 IC flashes showed a weak inverse relation between pulse amplitude and altitude. Amplitude of the largest IB pulse for 25 CG flashes showed no altitude correlation. Duration of the largest IB pulse in ICs averaged twice as long as in CGs (96 μs versus 46 μs), and all of the CG durations were <100 μs. Among the ICs, there is a positive relation between largest IB pulse duration and amplitude; the linear correlation coefficient is 0.385 with outliers excluded. The largest IB pulse in IC flashes typically occurred at a longer time after the first IB pulse (average 4.1 ms) than was the case in CG flashes (average 0.6 ms). In both flash types, the largest IB pulse was the first IB pulse in about 30% of the cases. In one storm all 42 IC flashes with triggered data had IB pulses.

Initial Breakdown Pulse Amplitudes in Intracloud and Cloud-to-Ground Lightning Flashes

NASA Astrophysics Data System (ADS)

Marshall, T. C.; Smith, E. M.; Stolzenburg, M.; Karunarathne, S.; Siedlecki, R. D., II

2017-12-01

This study analyzes the largest initial breakdown (IB) pulse in flashes from three storms in Florida. The study was motivated in part by the possibility that IB pulses of IC flashes may cause of terrestrial gamma-ray flashes (TGFs). The range-normalized, zero-to-peak amplitude of the largest IB pulse within each flash was determined along with its altitude, duration, and occurrence time in the flash. Appropriate data were available for 40 intracloud (IC) and 32 cloud-to-ground (CG) flashes. Histograms of the magnitude of the largest IB pulse amplitude by flash type were similar, with mean (median) values of 1.49 (1.05) V/m for IC flashes and -1.35 (-0.87) V/m for CG flashes. The mean amplitude of the largest IC IB pulses are substantially smaller (roughly an order of magnitude smaller) than the few known pulse amplitudes of TGF events and TGF candidate events. The largest IB pulse in 30 IC flashes showed a weak inverse relation between pulse amplitude and altitude. Amplitude of the largest IB pulse for 25 CG flashes showed no altitude correlation. Duration of the largest IB pulse in ICs averaged twice as long as in CGs (96 μs versus 46 μs); all of the CG durations were <100 μs. Among the ICs, there is a positive relation between largest IB pulse duration and amplitude; the linear correlation coefficient is 0.385 with outliers excluded. The largest IB pulse in IC flashes typically occurred at a longer time after the first IB pulse (average 4.1 ms) than was the case in CG flashes (average 0.6 ms). In both flash types, the largest IB pulse was the first IB pulse in about 30% of the cases.

Strong motion observations and recordings from the great Wenchuan Earthquake

USGS Publications Warehouse

Li, X.; Zhou, Z.; Yu, H.; Wen, R.; Lu, D.; Huang, M.; Zhou, Y.; Cu, J.

2008-01-01

The National Strong Motion Observation Network System (NSMONS) of China is briefly introduced in this paper. The NSMONS consists of permanent free-field stations, special observation arrays, mobile observatories and a network management system. During the Wenchuan Earthquake, over 1,400 components of acceleration records were obtained from 460 permanent free-field stations and three arrays for topographical effect and structural response observation in the network system from the main shock, and over 20,000 components of acceleration records from strong aftershocks occurred before August 1, 2008 were also obtained by permanent free-field stations of the NSMONS and 59 mobile instruments quickly deployed after the main shock. The strong motion recordings from the main shock and strong aftershocks are summarized in this paper. In the ground motion recordings, there are over 560 components with peak ground acceleration (PGA) over 10 Gal, the largest being 957.7 Gal. The largest PGA recorded during the aftershock exceeds 300 Gal. ?? 2008 Institute of Engineering Mechanics, China Earthquake Administration and Springer-Verlag GmbH.

Evaluation of agricultural best-management practices in the Conestoga River headwaters, Pennsylvania; effects of nutrient management on quality of surface runoff at a small carbonate-rock site near Ephrate, Pennsylvania, 1984-90

USGS Publications Warehouse

Hall, D.W.; Lietman, P.L.; Koerkle, E.J.

1997-01-01

The U.S. Geological Survey and the Pennsylvania Department of Environmental Protection conducted a study from 1984 to 1990 to determine theeffects of the implementation and practice of nutrient management [an agricultural best-management practice (BMP)] on the quality of surface runoff and ground water at a 55-acre crop and livestock farm in carbonate terrain nearEphrata, Pa. Implementation of nutrient management at Field-Site 2 resulted in application decreases of 33 percent for nitrogen and 29 percent for phosphorus. There wereno significant changes in nitrogen or phosphorusloads for a given amount of runoff from the pre-BMP to the post-BMP periods. However, less than 2 percent of the applied nutrients weredischarged with runoff throughout the study period.After the implementation of nutrient management, statistically significant decreases in concentrations of nitrate in ground-water samples occurred at threeof the four wells monitored throughout the pre- and post-BMP periods. The largest decreases in nitrate concentrations occurred at wells where samples hadthe largest nitrate concentrations prior to nutrient management. Changes in nitrogen applications to the contributing areas of five wells were correlated with nitrate concentrations of the well water. The correlations between the timing and amount of applied nitrogen and changes in ground-water quality met the four conditions that are characteristic of a cause-effect relation: an association, consistency, responsiveness, and a mechanism. Changes in ground-water nitrate concentrations lagged behind changes in loading of nitrogen fertilizers (primarily manure) by approximately 4 to 19 months.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Klein, Fred W.

A significant seismic hazard exists in south Hawaii from large tectonic earthquakes that can reach magnitude 8 and intensity XII. This paper quantifies the hazard by estimating the horizontal peak ground acceleration (PGA) in south Hawaii which occurs with a 90% probability of not being exceeded during exposure times from 10 to 250 years. The largest earthquakes occur beneath active, unbuttressed and mobile flanks of volcanoes in their shield building stage.

Remote Triggering in the Koyna-Warna Reservoir-Induced Seismic Zone, Western India

NASA Astrophysics Data System (ADS)

Bansal, Abhey Ram; Rao, N. Purnachandra; Peng, Zhigang; Shashidhar, D.; Meng, Xiaofeng

2018-03-01

Dynamic triggering following large distant earthquakes has been observed in many regions globally. In this study, we present evidence for remote dynamic triggering in the Koyna-Warna region of Western India, which is known to be a premier site of reservoir-induced seismicity. Using data from a closely spaced broadband network of 11 stations operated in the region since 2005, we conduct a systematic search for dynamic triggering following 20 large distant earthquakes with dynamic stresses of at least 1 kPa in the region. We find that the only positive cases of dynamic triggering occurred during 11 April 2012, Mw8.6 Indian Ocean earthquake and its largest aftershock of Mw8.2. In the first case, microearthquakes started to occur in the first few cycles of the Love waves, and the largest event of magnitude 3.3 occurred during the first few cycles of the Rayleigh waves. The increase of microseismicity lasted for up to five days, including a magnitude 4.8 event occurred approximately three days later. Our results suggest that the Koyna-Warna region is stress sensitive and susceptible for remote dynamic triggering, although the apparent triggering threshold appears to be slightly higher than other regions.

Maximum magnitude in the Lower Rhine Graben

NASA Astrophysics Data System (ADS)

Vanneste, Kris; Merino, Miguel; Stein, Seth; Vleminckx, Bart; Brooks, Eddie; Camelbeeck, Thierry

2014-05-01

Estimating Mmax, the assumed magnitude of the largest future earthquakes expected on a fault or in an area, involves large uncertainties. No theoretical basis exists to infer Mmax because even where we know the long-term rate of motion across a plate boundary fault, or the deformation rate across an intraplate zone, neither predict how strain will be released. As a result, quite different estimates can be made based on the assumptions used. All one can say with certainty is that Mmax is at least as large as the largest earthquake in the available record. However, because catalogs are often short relative to the average recurrence time of large earthquakes, larger earthquakes than anticipated often occur. Estimating Mmax is especially challenging within plates, where deformation rates are poorly constrained, large earthquakes are rarer and variable in space and time, and often occur on previously unrecognized faults. We explore this issue for the Lower Rhine Graben seismic zone where the largest known earthquake, the 1756 Düren earthquake, has magnitude 5.7 and should occur on average about every 400 years. However, paleoseismic studies suggest that earthquakes with magnitudes up to 6.7 occurred during the Late Pleistocene and Holocene. What to assume for Mmax is crucial for critical facilities like nuclear power plants that should be designed to withstand the maximum shaking in 10,000 years. Using the observed earthquake frequency-magnitude data, we generate synthetic earthquake histories, and sample them over shorter intervals corresponding to the real catalog's completeness. The maximum magnitudes appearing most often in the simulations tend to be those of earthquakes with mean recurrence time equal to the catalog length. Because catalogs are often short relative to the average recurrence time of large earthquakes, we expect larger earthquakes than observed to date to occur. In a next step, we will compute hazard maps for different return periods based on the synthetic catalogs, in order to determine the influence of underestimating Mmax.

Tocotrienols in Vellozia gigantea leaves: occurrence and modulation by seasonal and plant size effects.

PubMed

Morales, Melanie; Garcia, Queila S; Siqueira-Silva, Advanio I; Silva, Mayara C; Munné-Bosch, Sergi

2014-08-01

Vitamin E occurs in all photosynthetic organisms examined to date. Tocopherols predominate in photosynthetic tissues (α-tocopherol being the major form), while either tocopherols or tocotrienols (or both) are present in seeds. Tocotrienols have not been described in photosynthetic tissues thus far. Here, we report on the presence of tocotrienols in leaves of higher plants. Both tocopherols and tocotrienols accumulated in leaves of Vellozia gigantea, an endemic plant found in the rupestrian fields of Serra do Cipó, Brazil. Increased plant size had a remarkable effect on the vitamin E composition of leaves, α-tocopherol and β-tocotrienol levels being highest in the largest individuals, but only during the dry season. Vitamin E levels positively correlated with lipid hydroxyperoxide levels, which also increased in the largest individuals during the dry season. However, the maximum efficiency of PSII photochemistry (F v/F m ratio) kept above 0.75 throughout the experiment, thus indicating absence of photoinhibitory damage to the photosynthetic apparatus. It is concluded that higher plants, such as V. gigantea, can accumulate tocotrienols in leaves, aside from tocopherols, and that the levels of both tocopherols and tocotrienols in the leaves of this species are strongly modulated by seasonal and plant size effects.

Simulated effects of increased groundwater withdrawals in the Cave Springs area, Hixson, Tennessee

USGS Publications Warehouse

Haugh, Connor J.

2014-01-01

Under scenarios A and B, the largest change in the water budget occurs for flow to Cave Springs with decreases of 1.9 and 4.7 ft3/s, respectively. Similarly, groundwater discharge to North Chickamauga Creek decreases by 1.0 ft3/s and 2.6 ft33/s, respectively. Under scenarios C and D, the largest change in the water budget occurs for flow to Chickamauga Lake with decreases of 1.3 ft3/s and 2.3 ft3/s, respectively. Similarly, groundwater discharge to North Chickamauga Creek decreases by 1.1 ft3/s and 2.1 ft3/s, respectively. Changes in groundwater levels at the well fields were also analyzed. At the Cave Springs well field, maximum declines in groundwater levels due to additional pumpage are less than 1 foot for all scenarios. Groundwater level changes at the Cave Springs well field are small due to the highly transmissive nature of the aquifer in this location. Maximum groundwater-level declines at Walkers Corner are less than 1 foot for scenarios A and B and about 52 feet and 82 feet for scenarios C and D, respectively. Under scenarios C and D, the regional potentiometric surface shows a large cone of depression centered on the Walkers Corner well field and elongated along geologic strike.

Elevated amygdala response to faces and gaze aversion in autism spectrum disorder.

PubMed

Tottenham, Nim; Hertzig, Margaret E; Gillespie-Lynch, Kristen; Gilhooly, Tara; Millner, Alexander J; Casey, B J

2014-01-01

Autism spectrum disorders (ASD) are often associated with impairments in judgment of facial expressions. This impairment is often accompanied by diminished eye contact and atypical amygdala responses to face stimuli. The current study used a within-subjects design to examine the effects of natural viewing and an experimental eye-gaze manipulation on amygdala responses to faces. Individuals with ASD showed less gaze toward the eye region of faces relative to a control group. Among individuals with ASD, reduced eye gaze was associated with higher threat ratings of neutral faces. Amygdala signal was elevated in the ASD group relative to controls. This elevated response was further potentiated by experimentally manipulating gaze to the eye region. Potentiation by the gaze manipulation was largest for those individuals who exhibited the least amount of naturally occurring gaze toward the eye region and was associated with their subjective threat ratings. Effects were largest for neutral faces, highlighting the importance of examining neutral faces in the pathophysiology of autism and questioning their use as control stimuli with this population. Overall, our findings provide support for the notion that gaze direction modulates affective response to faces in ASD.

Review: Modelling of meniscus of knee joint during soccer kicking

NASA Astrophysics Data System (ADS)

Azrul Hisham Mohd Adib, Mohd; Firdaus Jaafar, Mohd

2013-12-01

Knee is a part of the body that located between thigh and shank is one of the most complicated and largest joints in the human body. The common injuries that occur are ligaments, meniscus or bone fracture. During soccer games, the knee is the most critical part that will easily injure due to the shock from an external impact. Torn meniscus is one of the effects. This study will investigate the effect towards the meniscus within the knee joint during soccer ball kicking. We conduct a literary review of 14 journals that discuss the general view of meniscus and also soccer kicking. The selected topics for this review paper are meniscal function, meniscal movement, meniscal tears and also instep kick. As a finding, statistics show that most meniscal tears (73%) occurred in athletes who were soccer players, basketball players or skiers. The tear is frequently happening at the medial side rather than lateral side with a percentage of 70%.

Storm-surge flooding on the Yukon-Kuskokwim Delta, Alaska

USGS Publications Warehouse

Terenzi, John; Ely, Craig R.; Jorgenson, M. Torre

2014-01-01

Coastal regions of Alaska are regularly affected by intense storms of ocean origin, the frequency and intensity of which are expected to increase as a result of global climate change. The Yukon-Kuskokwim Delta (YKD), situated in western Alaska on the eastern edge of the Bering Sea, is one of the largest deltaic systems in North America. Its low relief makes it especially susceptible to storm-driven flood tides and increases in sea level. Little information exists on the extent of flooding caused by storm surges in western Alaska and its effects on salinization, shoreline erosion, permafrost thaw, vegetation, wildlife, and the subsistence-based economy. In this paper, we summarize storm flooding events in the Bering Sea region of western Alaska during 1913 – 2011 and map both the extent of inland flooding caused by autumn storms on the central YKD, using Radarsat-1 and MODIS satellite imagery, and the drift lines, using high-resolution IKONOS satellite imagery and field surveys. The largest storm surges occurred in autumn and were associated with high tides and strong (> 65 km hr-1) southwest winds. Maximum inland extent of flooding from storm surges was 30.3 km in 2005, 27.4 km in 2006, and 32.3 km in 2011, with total flood area covering 47.1%, 32.5%, and 39.4% of the 6730 km2 study area, respectively. Peak stages for the 2005 and 2011 storms were 3.1 m and 3.3 m above mean sea level, respectively—almost as high as the 3.5 m amsl elevation estimated for the largest storm observed (in November 1974). Several historically abandoned village sites lie within the area of inundation of the largest flood events. With projected sea level rise, large storms are expected to become more frequent and cover larger areas, with deleterious effects on freshwater ponds, non-saline habitats, permafrost, and landscapes used by nesting birds and local people.

Far-field pressurization likely caused one of the largest injection induced earthquakes by reactivating a large pre-existing basement fault structure

USGS Publications Warehouse

Yeck, William; Weingarten, Matthew; Benz, Harley M.; McNamara, Daniel E.; Bergman, E.; Herrmann, R.B; Rubinstein, Justin L.; Earle, Paul

2016-01-01

The Mw 5.1 Fairview, Oklahoma, earthquake on 13 February 2016 and its associated seismicity produced the largest moment release in the central and eastern United States since the 2011 Mw 5.7 Prague, Oklahoma, earthquake sequence and is one of the largest earthquakes potentially linked to wastewater injection. This energetic sequence has produced five earthquakes with Mw 4.4 or larger. Almost all of these earthquakes occur in Precambrian basement on a partially unmapped 14 km long fault. Regional injection into the Arbuckle Group increased approximately sevenfold in the 36 months prior to the start of the sequence (January 2015). We suggest far-field pressurization from clustered, high-rate wells greater than 12 km from this sequence induced these earthquakes. As compared to the Fairview sequence, seismicity is diffuse near high-rate wells, where pressure changes are expected to be largest. This points to the critical role that preexisting faults play in the occurrence of large induced earthquakes.

Effectiveness of the cigarette ignition propensity standard in preventing unintentional residential fires in Massachusetts.

PubMed

Alpert, Hillel R; Christiani, David C; Orav, E John; Dockery, Douglas W; Connolly, Gregory N

2014-04-01

We evaluated the Massachusetts Fire Safe Cigarette Law's (FSCL's) effectiveness in preventing residential fires. We examined unintentional residential fires reported to the Massachusetts Fire Incident Reporting System from 2004 to 2010. We analyzed FSCL effect on the likelihood of cigarette- versus noncigarette-caused fires and effect modification by fire scenario factors by using an interrupted time series regression model. We analyzed the effect of FSCL on monthly fire rates with Poisson regression. Cigarettes caused 1629 unintentional residential fires during the study period. The FSCL was associated with a 28% (95% confidence interval = 12%, 41%) reduction in the odds of cigarette- versus noncigarette-caused fires, although not in analyses restricted to casualty fires, with smaller sample size. The largest reductions were among fires in which human factors were involved; that were first ignited on furniture, bedding, or soft goods; that occurred in living areas; or that occurred in the summer or winter. The FSCL appears to have decreased the likelihood of cigarette-caused residential fires, particularly in scenarios for which the ignition propensity standard was developed. Current standards should be adopted, and the need for strengthening should be considered.

Effectiveness of the Cigarette Ignition Propensity Standard in Preventing Unintentional Residential Fires in Massachusetts

PubMed Central

Christiani, David C.; Orav, E. John; Dockery, Douglas W.; Connolly, Gregory N.

2014-01-01

Objectives. We evaluated the Massachusetts Fire Safe Cigarette Law’s (FSCL’s) effectiveness in preventing residential fires. Methods. We examined unintentional residential fires reported to the Massachusetts Fire Incident Reporting System from 2004 to 2010. We analyzed FSCL effect on the likelihood of cigarette- versus noncigarette-caused fires and effect modification by fire scenario factors by using an interrupted time series regression model. We analyzed the effect of FSCL on monthly fire rates with Poisson regression. Results. Cigarettes caused 1629 unintentional residential fires during the study period. The FSCL was associated with a 28% (95% confidence interval = 12%, 41%) reduction in the odds of cigarette- versus noncigarette-caused fires, although not in analyses restricted to casualty fires, with smaller sample size. The largest reductions were among fires in which human factors were involved; that were first ignited on furniture, bedding, or soft goods; that occurred in living areas; or that occurred in the summer or winter. Conclusions. The FSCL appears to have decreased the likelihood of cigarette-caused residential fires, particularly in scenarios for which the ignition propensity standard was developed. Current standards should be adopted, and the need for strengthening should be considered. PMID:24524537

Shortleaf pine seed production in natural stands in the Ouachita and Ozark mountains

Treesearch

Michael G. Shelton; Robert F. Wittwer

1996-01-01

Seed production of shortleaf pine (Pinus echinata Mill.) was monitored from 1965 to 1974 to determine the periodicity qf seed crops in both woods-run stands and seed-production areas. One bumper and two good seed crops occurred during the 9-yr period. The two largest crops occurred in successive years, then seed production was low for 4 yr before...

Mechanical properties of multilayered films using different nanoindenters.

PubMed

Fang, Te-Hua; Wang, Tong Hong; Wu, Jia-Hung

2010-07-01

The effects of interface, contact hardness, deformation, and adhesion of Al/Ni multilayered films under nanoindentation were investigated using molecular dynamics (MD) simulations. The results show that the indentation force of the sphere indenter is the largest among nanoindentations using sphere, cone, Vickers, or Berkovich type indenters at the same penetration depth. Force increasing, relaxation and adhesion took place during loading, holding depth and unloading, respectively. The interface occurred along the {111} (110) slip systems and the maximum width of the glide bands was about 1 nm. The reaction force and plastic energy of the indented films are also discussed.

Reach and messages of the world's largest ivory burn.

PubMed

Braczkowski, Alexander; Holden, Matthew H; O'Bryan, Christopher; Choi, Chi-Yeung; Gan, Xiaojing; Beesley, Nicholas; Gao, Yufang; Allan, James; Tyrrell, Peter; Stiles, Daniel; Brehony, Peadar; Meney, Revocatus; Brink, Henry; Takashina, Nao; Lin, Ming-Ching; Lin, Hsien-Yung; Rust, Niki; Salmo, Severino G; Watson, James E M; Kahumbu, Paula; Maron, Martine; Possingham, Hugh P; Biggs, Duan

2018-03-01

Recent increases in ivory poaching have depressed African elephant populations. Successful enforcement has led to ivory stockpiling. Stockpile destruction is becoming increasingly popular, and most destruction has occurred in the last 5 years. Ivory destruction is intended to send a strong message against ivory consumption, both in promoting a taboo on ivory use and catalyzing policy change. However, there has been no effort to establish the distribution and extent of media reporting on ivory destruction events globally. We analyzed media coverage of the largest ivory destruction event in history (Kenya, 30 April 2016) across 11 nation states connected to ivory trade. We used an online-media crawling tool to search online media outlets and subjected 5 of the largest print newspapers (by circulation) in 5 nations of interest to content analysis. Most online news on the ivory burn came from the United States (81% of 1944 articles), whereas most of the print news articles came from Kenya (61% of 157 articles). Eighty-six to 97% of all online articles reported the burn as a positive conservation action, whereas 4-50% discussed ivory burning as having a negative impact on elephant conservation. Most articles discussed law enforcement and trade bans as effective for elephant conservation. There was more relative search interest globally in the 2016 Kenyan ivory burn than any other burn in 5 years. Ours is the first attempt to track the reach of media coverage relative to an ivory burn and provides a case study in tracking the effects of a conservation-marketing event. © 2018 Society for Conservation Biology.

Efficacy of memory rehabilitation therapy: a meta-analysis of TBI and stroke cognitive rehabilitation literature.

PubMed

Elliott, Madison; Parente, Frederick

2014-01-01

To examine the efficacy of cognitive rehabilitation strategies specifically designed to improve memory after traumatic brain injury (TBI) and stroke vs. memory improvement with the passage of time. A meta-analysis was performed on 26 studies of memory retraining and recovery that were published between the years of 1985 and 2013. Effect sizes (ESs) from each study were calculated and converted to Pearson's r and then analysed to assess the overall effect size and the relationship among the ESs, patient demographics and treatment interventions. RESULTS indicated a significant average ES (r = 0.51) in the treatment intervention conditions, as well as a significant average ES (r = 0.31) in the control conditions, in which participants did not receive any treatment. The largest ESs occurred in studies of stroke patients and studies concerning working memory rehabilitation. RESULTS showed that memory rehabilitation was an effective therapeutic intervention, especially for stroke patients and for working memory as a treatment domain. However, the results also indicated that significant memory improvement occurred spontaneously over time.

[The journey of Legionella pneumophila from amoebae to macrophage. Reflections on the largest outbreak of legionnaire's disease].

PubMed

Segovia Hernández, Manuel

2005-01-01

Legionella, the causative agent of legionnaire's disease (LD), can survive and grow in amoebic cells. Free-living amoebae may play a role in the selection of virulence traits and in adaptation to survival in macrophages, and represent an important reservoir of Legionella. These amoebae may act as a Trojan horse bringing hidden bacteria within the human environments. The community outbreak of LD that occurred in Murcia in July 2001, the largest such outbreak ever reported, afforded an unusual opportunity to improve the knowledge of this disease.

Scale effects and a method for similarity evaluation in micro electrical discharge machining

NASA Astrophysics Data System (ADS)

Liu, Qingyu; Zhang, Qinhe; Wang, Kan; Zhu, Guang; Fu, Xiuzhuo; Zhang, Jianhua

2016-08-01

Electrical discharge machining(EDM) is a promising non-traditional micro machining technology that offers a vast array of applications in the manufacturing industry. However, scale effects occur when machining at the micro-scale, which can make it difficult to predict and optimize the machining performances of micro EDM. A new concept of "scale effects" in micro EDM is proposed, the scale effects can reveal the difference in machining performances between micro EDM and conventional macro EDM. Similarity theory is presented to evaluate the scale effects in micro EDM. Single factor experiments are conducted and the experimental results are analyzed by discussing the similarity difference and similarity precision. The results show that the output results of scale effects in micro EDM do not change linearly with discharge parameters. The values of similarity precision of machining time significantly increase when scaling-down the capacitance or open-circuit voltage. It is indicated that the lower the scale of the discharge parameter, the greater the deviation of non-geometrical similarity degree over geometrical similarity degree, which means that the micro EDM system with lower discharge energy experiences more scale effects. The largest similarity difference is 5.34 while the largest similarity precision can be as high as 114.03. It is suggested that the similarity precision is more effective in reflecting the scale effects and their fluctuation than similarity difference. Consequently, similarity theory is suitable for evaluating the scale effects in micro EDM. This proposed research offers engineering values for optimizing the machining parameters and improving the machining performances of micro EDM.

World's largest macroalgal bloom caused by expansion of seaweed aquaculture in China.

PubMed

Liu, Dongyan; Keesing, John K; Xing, Qianguo; Shi, Ping

2009-06-01

In late June 2008, just weeks before the opening of the Beijing Olympics, a massive green-tide occurred covering about 600km(2) along the coast of Qingdao, host city for Olympic sailing regatta. Coastal eutrophication was quickly attributed with the blame by the international media and some scientists. However, we explored an alternative hypothesis that the cause of the green-tide was due to the rapid expansion of Porphyra yezoensis aquaculture along the coastline over 180km away from Qingdao, and oceanographic conditions which favoured rapid growth of the bloom and contributed to transport of the bloom north into the Yellow Sea and then onshore northwest to Qingdao. At its peak offshore, the bloom covered 1200km(2) and affected 40,000km(2). This is the largest green-tide ever reported, the most extensive translocation of a green-tide and the first case of expansive seaweed aquaculture leading to a green-tide. Given similar oceanographic conditions to those that occurred in 2008, these green-tides may re-occur unless mitigation measures such as those proposed here are taken.

Climate Response of Direct Radiative Forcing of Anthropogenic Black Carbon

NASA Technical Reports Server (NTRS)

Chung, Serena H.; Seinfeld,John H.

2008-01-01

The equilibrium climate effect of direct radiative forcing of anthropogenic black carbon (BC) is examined by 100-year simulations in the Goddard Institute for Space Studies General Circulation Model II-prime coupled to a mixed-layer ocean model. Anthropogenic BC is predicted to raise globally and annually averaged equilibrium surface air temperature by 0.20 K if BC is assumed to be externally mixed. The predicted increase is significantly greater in the Northern Hemisphere (0.29 K) than in the Southern Hemisphere (0.11 K). If BC is assumed to be internally mixed with the present day level of sulfate aerosol, the predicted annual mean surface temperature increase rises to 0.37 K globally, 0.54 K for the Northern Hemisphere, and 0.20 K for the Southern Hemisphere. The climate sensitivity of BC direct radiative forcing is calculated to be 0.6 K W (sup -1) square meters, which is about 70% of that of CO2, independent of the assumption of BC mixing state. The largest surface temperature response occurs over the northern high latitudes during winter and early spring. In the tropics and midlatitudes, the largest temperature increase is predicted to occur in the upper troposphere. Direct radiative forcing of anthropogenic BC is also predicted to lead to a change of precipitation patterns in the tropics; precipitation is predicted to increase between 0 and 20 N and decrease between 0 and 20 S, shifting the intertropical convergence zone northward. If BC is assumed to be internally mixed with sulfate instead of externally mixed, the change in precipitation pattern is enhanced. The change in precipitation pattern is not predicted to alter the global burden of BC significantly because the change occurs predominantly in regions removed from BC sources.

SAFE HANDLING OF FOODS

EPA Science Inventory

Microbial food-borne illnesses pose a significant health problem in Japan. In 1996 the world's largest outbreak of Escherichia coli food illness occurred in Japan. Since then, new regulatory measures were established, including strict hygiene practices in meat and food processi...

The 1991 eruptions of Mount Pinatubo, Philippines

USGS Publications Warehouse

Wolfe, Edward W.

1992-01-01

Recognition of the volcanic unrest at Mount Pinatubo in the Philippines began when steam explosions occurred on April 2, 1991. The unrest culminated ten weeks later in the world's largest eruption in more than half a century. 

Legionnaires' Disease Outbreaks and Cooling Towers, New York City, New York, USA.

PubMed

Fitzhenry, Robert; Weiss, Don; Cimini, Dan; Balter, Sharon; Boyd, Christopher; Alleyne, Lisa; Stewart, Renee; McIntosh, Natasha; Econome, Andrea; Lin, Ying; Rubinstein, Inessa; Passaretti, Teresa; Kidney, Anna; Lapierre, Pascal; Kass, Daniel; Varma, Jay K

2017-11-01

The incidence of Legionnaires' disease in the United States has been increasing since 2000. Outbreaks and clusters are associated with decorative, recreational, domestic, and industrial water systems, with the largest outbreaks being caused by cooling towers. Since 2006, 6 community-associated Legionnaires' disease outbreaks have occurred in New York City, resulting in 213 cases and 18 deaths. Three outbreaks occurred in 2015, including the largest on record (138 cases). Three outbreaks were linked to cooling towers by molecular comparison of human and environmental Legionella isolates, and the sources for the other 3 outbreaks were undetermined. The evolution of investigation methods and lessons learned from these outbreaks prompted enactment of a new comprehensive law governing the operation and maintenance of New York City cooling towers. Ongoing surveillance and program evaluation will determine if enforcement of the new cooling tower law reduces Legionnaires' disease incidence in New York City.

Legionnaires’ Disease Outbreaks and Cooling Towers, New York City, New York, USA

PubMed Central

Fitzhenry, Robert; Cimini, Dan; Balter, Sharon; Boyd, Christopher; Alleyne, Lisa; Stewart, Renee; McIntosh, Natasha; Econome, Andrea; Lin, Ying; Rubinstein, Inessa; Passaretti, Teresa; Kidney, Anna; Lapierre, Pascal; Kass, Daniel; Varma, Jay K.

2017-01-01

The incidence of Legionnaires’ disease in the United States has been increasing since 2000. Outbreaks and clusters are associated with decorative, recreational, domestic, and industrial water systems, with the largest outbreaks being caused by cooling towers. Since 2006, 6 community-associated Legionnaires’ disease outbreaks have occurred in New York City, resulting in 213 cases and 18 deaths. Three outbreaks occurred in 2015, including the largest on record (138 cases). Three outbreaks were linked to cooling towers by molecular comparison of human and environmental Legionella isolates, and the sources for the other 3 outbreaks were undetermined. The evolution of investigation methods and lessons learned from these outbreaks prompted enactment of a new comprehensive law governing the operation and maintenance of New York City cooling towers. Ongoing surveillance and program evaluation will determine if enforcement of the new cooling tower law reduces Legionnaires’ disease incidence in New York City. PMID:29049017

Characterization of increased persistence and intensity of precipitation in the northeastern United States

NASA Astrophysics Data System (ADS)

Guilbert, Justin; Betts, Alan K.; Rizzo, Donna M.; Beckage, Brian; Bomblies, Arne

2015-03-01

We present evidence of increasing persistence in daily precipitation in the northeastern United States that suggests that global circulation changes are affecting regional precipitation patterns. Meteorological data from 222 stations in 10 northeastern states are analyzed using Markov chain parameter estimates to demonstrate that a significant mode of precipitation variability is the persistence of precipitation events. We find that the largest region-wide trend in wet persistence (i.e., the probability of precipitation in 1 day and given precipitation in the preceding day) occurs in June (+0.9% probability per decade over all stations). We also find that the study region is experiencing an increase in the magnitude of high-intensity precipitation events. The largest increases in the 95th percentile of daily precipitation occurred in April with a trend of +0.7 mm/d/decade. We discuss the implications of the observed precipitation signals for watershed hydrology and flood risk.

The characteristics on spatiotemporal variations of summer heatwaves in China

NASA Astrophysics Data System (ADS)

Qixiang, C.; Wang, L.; Wu, S., II; Li, Y.

2016-12-01

Summer heatwaves in China have impacts on forestry, agriculture resource, infrastructure, and heat -related illness and mortality. Based on daily air temperature and relative humidity from the Chinese Meteorological Data Sharing Service System, the spatial distribution and trends of the intensity, duration, and frequency of heatwaves in China during 1960-2015 were analyzed. Considering climatic variability, we defined a heatwave as a spell of consecutive days with maximum temperatures exceeding the relative threshold (temperature percentile) .We also consider a indices combined hot days and tropical nights (CHT), and the humidity-corrected apparent temperature (AT) to analyze the health impacts of hot days in summer. This study shows that while the average frequency and duration of heatwaves has an increasing trend since 1990s, the North China Plain has a decreasing trend. This study also shows that the largest CHT values occur in southeast China, and the largest AT values occur in South China.

Catastrophic lava dome failure at Soufrière Hills Volcano, Montserrat, 12-13 July 2003

USGS Publications Warehouse

Herd, Richard A.; Edmonds, Marie; Bass, Venus A.

2005-01-01

The lava dome collapse of 12–13 July 2003 was the largest of the Soufrière Hills Volcano eruption thus far (1995–2005) and the largest recorded in historical times from any volcano; 210 million m3 of dome material collapsed over 18 h and formed large pyroclastic flows, which reached the sea. The evolution of the collapse can be interpreted with reference to the complex structure of the lava dome, which comprised discrete spines and shear lobes and an apron of talus. Progressive slumping of talus for 10 h at the beginning of the collapse generated low-volume pyroclastic flows. It undermined the massive part of the lava dome and eventually prompted catastrophic failure. From 02:00 to 04:40 13 July 2003 large pyroclastic flows were generated; these reached their largest magnitude at 03:35, when the volume flux of material lost from the lava dome probably approached 16 million m3 over two minutes. The high flux of pyroclastic flows into the sea caused a tsunami and a hydrovolcanic explosion with an associated pyroclastic surge, which flowed inland. A vulcanian explosion occurred during or immediately after the largest pyroclastic flows at 03:35 13 July and four further explosions occurred at progressively longer intervals during 13–15 July 2003. The dome collapse lasted approximately 18 h, but 170 of the total 210 million m3 was removed in only 2.6 h during the most intense stage of the collapse.

The largest glitch observed in the Crab pulsar

NASA Astrophysics Data System (ADS)

Shaw, B.; Lyne, A. G.; Stappers, B. W.; Weltevrede, P.; Bassa, C. G.; Lien, A. Y.; Mickaliger, M. B.; Breton, R. P.; Jordan, C. A.; Keith, M. J.; Krimm, H. A.

2018-05-01

We have observed a large glitch in the Crab pulsar (PSR B0531+21). The glitch occurred around MJD 58064 (2017 November 8) when the pulsar underwent an increase in the rotation rate of Δν = 1.530 × 10-5 Hz, corresponding to a fractional increase of Δν/ν = 0.516 × 10-6 making this event the largest glitch ever observed in this source. Due to our high-cadence and long-dwell time observations of the Crab pulsar we are able to partially resolve a fraction of the total spin-up of the star. This delayed spin-up occurred over a timescale of ˜1.7 days and is similar to the behaviour seen in the 1989 and 1996 large Crab pulsar glitches. The spin-down rate also increased at the glitch epoch by Δ \\dot{ν } / \\dot{ν } = 7 × 10^{-3}. In addition to being the largest such event observed in the Crab, the glitch occurred after the longest period of glitch inactivity since at least 1984 and we discuss a possible relationship between glitch size and waiting time. No changes to the shape of the pulse profile were observed near the glitch epoch at 610 MHz or 1520 MHz, nor did we identify any changes in the X-ray flux from the pulsar. The long-term recovery from the glitch continues to progress as \\dot{ν } slowly rises towards pre-glitch values. In line with other large Crab glitches, we expect there to be a persistent change to \\dot{ν }. We continue to monitor the long-term recovery with frequent, high quality observations.

The effect of inertial loading on wrist postural tremor in essential tremor.

PubMed

Héroux, M E; Pari, G; Norman, K E

2009-05-01

Determine the effect of inertial loading on the strength of motor unit entrainment and the synergistic/competitive interaction between central and mechanical reflex tremor components in subjects with essential tremor (ET). Twenty-three subjects with ET and 22 controls held their hand in an outstretched position while supporting sub-maximal loads (no-load, 5%, 15% and 25% 1-repetition maximum). Hand postural tremor and wrist extensor neuromuscular activity were recorded. Inertial loading resulted in a reduction in postural tremor in all ET subjects. The largest reduction in tremor amplitude occurred between 5% and 15% loads, which was associated with spectral separation of the mechanical reflex and central tremor components in a large number of ET subjects. Despite an increase in overall neuromuscular activity with inertial loading, EMG tremor spectral power did not increase with loading. The effect of inertial loading on postural tremor amplitude appears to be mediated in large part by its effect on the interaction between mechanical reflex and central tremor components. Also, ET is associated with a constant absolute level of motor unit entrainment. The amplitude of postural tremor is dependent on both central and peripheral factors, with proportionally greater motor unit entrainment occurring at low contraction intensities.

Using walker during walking: a pilot study for health elder.

PubMed

Po-Chan, Yeh; Cherng-Yee, Leung

2012-01-01

Walker operation completely relies on the walker handle, however most marketed walkers possess two horizontal handles. Several researchers have suggested that horizontal handles might lead to wrist injury. Therefore, the purpose of this study is to assess the relevant design aspects of walker for elderly people. 28 elders participated in this study; when the experiment was started, subject walked on the tile for 3 meter distance twice by using walker. Data for analysis were selected at the corresponding wrist deviation and vertical force. The results showed that during walker using, the mean wrist deviation was greater than zero. The largest vertical force is significantly larger than the smallest one, and different wrist deviation occurred at three phases, the largest wrist deviation while raising walker is larger than the smallest one, however, no significant different was found between the largest and smallest wrist deviation while pressing walker. No significant correlation occurred between weight and wrist deviation. The correlation between weight and vertical force was significantly positive. With wrist deviation walker use may cause injury to upper-limb, however wrists remain in a neutral position during hand movement to prevent damage. The findings of this study should improve the design of walker handles to reduce the wrist deviations of users.

Patient motion effects on the quantification of regional myocardial blood flow with dynamic PET imaging.

PubMed

Hunter, Chad R R N; Klein, Ran; Beanlands, Rob S; deKemp, Robert A

2016-04-01

Patient motion is a common problem during dynamic positron emission tomography (PET) scans for quantification of myocardial blood flow (MBF). The purpose of this study was to quantify the prevalence of body motion in a clinical setting and evaluate with realistic phantoms the effects of motion on blood flow quantification, including CT attenuation correction (CTAC) artifacts that result from PET-CT misalignment. A cohort of 236 sequential patients was analyzed for patient motion under resting and peak stress conditions by two independent observers. The presence of motion, affected time-frames, and direction of motion was recorded; discrepancy between observers was resolved by consensus review. Based on these results, patient body motion effects on MBF quantification were characterized using the digital NURBS-based cardiac-torso phantom, with characteristic time activity curves (TACs) assigned to the heart wall (myocardium) and blood regions. Simulated projection data were corrected for attenuation and reconstructed using filtered back-projection. All simulations were performed without noise added, and a single CT image was used for attenuation correction and aligned to the early- or late-frame PET images. In the patient cohort, mild motion of 0.5 ± 0.1 cm occurred in 24% and moderate motion of 1.0 ± 0.3 cm occurred in 38% of patients. Motion in the superior/inferior direction accounted for 45% of all detected motion, with 30% in the superior direction. Anterior/posterior motion was predominant (29%) in the posterior direction. Left/right motion occurred in 24% of cases, with similar proportions in the left and right directions. Computer simulation studies indicated that errors in MBF can approach 500% for scans with severe patient motion (up to 2 cm). The largest errors occurred when the heart wall was shifted left toward the adjacent lung region, resulting in a severe undercorrection for attenuation of the heart wall. Simulations also indicated that the magnitude of MBF errors resulting from motion in the superior/inferior and anterior/posterior directions was similar (up to 250%). Body motion effects were more detrimental for higher resolution PET imaging (2 vs 10 mm full-width at half-maximum), and for motion occurring during the mid-to-late time-frames. Motion correction of the reconstructed dynamic image series resulted in significant reduction in MBF errors, but did not account for the residual PET-CTAC misalignment artifacts. MBF bias was reduced further using global partial-volume correction, and using dynamic alignment of the PET projection data to the CT scan for accurate attenuation correction during image reconstruction. Patient body motion can produce MBF estimation errors up to 500%. To reduce these errors, new motion correction algorithms must be effective in identifying motion in the left/right direction, and in the mid-to-late time-frames, since these conditions produce the largest errors in MBF, particularly for high resolution PET imaging. Ideally, motion correction should be done before or during image reconstruction to eliminate PET-CTAC misalignment artifacts.

Static stress transfer during the 2002 Nenana Mountain-Denali Fault, Alaska, earthquake sequence

USGS Publications Warehouse

Anderson, G.; Ji, C.

2003-01-01

On 23 October 2002, the Mw 6.7 Nenana Mountain earthquake occurred in central Alaska. It was followed on 3 November 2002 by the Mw 7.9 Denali Fault mainshock, the largest strike-slip earthquake to occur in North America during the past 150 years. We have modeled static Coulomb stress transfer effects during this sequence. We find that the Nenana Mountain foreshock transferred 30-50 kPa of Coulomb stress to the hypocentral region of the Denali Fault mainshock, encouraging its occurrence. We also find that the two main earthquakes together transferred more than 400 kPa of Coulomb stress to the Cross Creek segment of the Totschunda fault system and to the Denali fault southeast of the mainshock rupture, and up to 80 kPa to the Denali fault west of the Nenana Mountain rupture. Other major faults in the region experienced much smaller static Coulomb stress changes.

The effect of engine operating conditions on exhaust gas recirculation cooler fouling

DOE PAGES

Lance, Michael J.; Mills, Zachary G.; Seylar, Joshua C.; ...

2018-05-17

Exhaust gas recirculation (EGR) cooler fouling occurs when particulate matter (PM) and hydrocarbons (HC) in diesel exhaust form a deposit on the walls of the EGR cooler through thermophoresis and condensation. To better understand the mechanisms controlling deposit formation and removal and how operating conditions can affect cooler performance, 20 identical tube-in-shell EGR coolers with sinusoidal fins were fouled using a 5-factor, 3-level experimental design. The deposit thickness was measured using two methods: (1) epoxy-mounting and polishing cooler cross-sections and comparing deposit thicknesses on the primary (outer tube) to the secondary (fins) heat transfer surfaces, and (2) milling tube sectionsmore » such that the surface of a fin could be observed and measuring the deposit thickness across the fin using a 3D profilometer. Near the cooler inlet, high inlet gas temperatures reduced deposit thickness by promoting mud-cracking and spallation. Near the middle of the cooler, the flow rate had the largest impact on the deposit thickness through the effect on residence time of the PM. The HC concentration along with flow rate had the largest effects near the cooler outlet where the lower temperatures allows for more HC condensation. Furthermore, these insights into how engine operating conditions influence the development of fouling layers in EGR coolers learned through this study will aid in the development of more fouling resistant coolers in the future.« less

The effect of engine operating conditions on exhaust gas recirculation cooler fouling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lance, Michael J.; Mills, Zachary G.; Seylar, Joshua C.

Exhaust gas recirculation (EGR) cooler fouling occurs when particulate matter (PM) and hydrocarbons (HC) in diesel exhaust form a deposit on the walls of the EGR cooler through thermophoresis and condensation. To better understand the mechanisms controlling deposit formation and removal and how operating conditions can affect cooler performance, 20 identical tube-in-shell EGR coolers with sinusoidal fins were fouled using a 5-factor, 3-level experimental design. The deposit thickness was measured using two methods: (1) epoxy-mounting and polishing cooler cross-sections and comparing deposit thicknesses on the primary (outer tube) to the secondary (fins) heat transfer surfaces, and (2) milling tube sectionsmore » such that the surface of a fin could be observed and measuring the deposit thickness across the fin using a 3D profilometer. Near the cooler inlet, high inlet gas temperatures reduced deposit thickness by promoting mud-cracking and spallation. Near the middle of the cooler, the flow rate had the largest impact on the deposit thickness through the effect on residence time of the PM. The HC concentration along with flow rate had the largest effects near the cooler outlet where the lower temperatures allows for more HC condensation. Furthermore, these insights into how engine operating conditions influence the development of fouling layers in EGR coolers learned through this study will aid in the development of more fouling resistant coolers in the future.« less

Evaporation of a Volatile Liquid Lens on the Surface of an Immiscible Liquid.

PubMed

Sun, Wei; Yang, Fuqian

2016-06-21

The evaporation behavior of toluene and hexane lenses on the surface of deionized (DI) water is studied. The toluene and hexane lenses during evaporation experience an advancing stage and a receding stage. There exists a significant difference of the evaporation behavior between the toluene lenses and the hexane lenses. The lifetime and largest diameter of both the toluene and hexane lenses increase with increasing the initial volume of the lenses. For the evaporation of the toluene lenses, the lifetime and largest diameter of the lenses decrease with increasing the temperature of DI water. The effect of the residual of the oil molecules on the evaporation of toluene lenses at a temperature of 21 °C is investigated via the evaporation of a series of consecutive toluene lenses being placed on the same position of the surface of DI water. The temporal evolution of the toluene lenses placed after the first toluene lens deviates significantly from that of the first toluene lens. Significant increase of the receding speed occurs at the dimensionless time in a range 0.7-0.8.

Effect of particle size distribution on 3D packings of spherical particles

NASA Astrophysics Data System (ADS)

Taiebat, Mahdi; Mutabaruka, Patrick; Pellenq, Roland; Radjai, Farhang

2017-06-01

We use molecular dynamics simulations of frictionless spherical particles to investigate a class of polydisperse granular materials in which the particle size distribution is uniform in particle volumes. The particles are assembled in a box by uniaxial compaction under the action of a constant stress. Due to the absence of friction and the nature of size distribution, the generated packings have the highest packing fraction at a given size span, defined as the ratio α of the largest size to the smallest size. We find that, up to α = 5, the packing fraction is a nearly linear function of α. While the coordination number is nearly constant due to the isostatic nature of the packings, we show that the connectivity of the particles evolves with α. In particular, the proportion of particles with 4 contacts represents the largest proportion of particles mostly of small size. We argue that this particular class of particles occurs as a result of the high stability of local configurations in which a small particle is stuck by four larger particles.

Advanced Supersonic Technology concept AST-100 characteristics developed in a baseline-update study

NASA Technical Reports Server (NTRS)

Baber, H. T., Jr.; Swanson, E. E.

1976-01-01

The advanced supersonic technology configuration, AST-100, is described. The combination of wing thickness reduction, nacelle recontouring for minimum drag at cruise, and the use of the horizontal tail to produce lift during climb and cruise resulted in an increase in maximum lift-to-drag ratio. Lighter engines and lower fuel weight associated with this resizing result in a six percent reduction in takeoff gross weight. The AST-100 takeoff maximum effective perceived noise at the runway centerline and sideline measurement stations was 114.4 decibels. Since 1.5-decibels tradeoff is available from the approach noise, the required engine noise supression is 4.9 decibels. The AST-100 largest maximum overpressure would occur during transonic climb acceleration when the aircraft was at relatively low altitude. Calculated standard +8 C day range of the AST-100, with a 292 passenger payload, is 7348 km (3968 n.mi). Fuel price is the largest contributor to direct operating cost. However, if the AST-100 were flown subsonically (M = 0.9), direct operating costs would increase approximately 50 percent because of time related costs.

High-frequency source radiation during the 2011 Tohoku-Oki earthquake, Japan, inferred from KiK-net strong-motion seismograms

NASA Astrophysics Data System (ADS)

Kumagai, Hiroyuki; Pulido, Nelson; Fukuyama, Eiichi; Aoi, Shin

2013-01-01

investigate source processes of the 2011 Tohoku-Oki earthquake, we utilized a source location method using high-frequency (5-10 Hz) seismic amplitudes. In this method, we assumed far-field isotropic radiation of S waves, and conducted a spatial grid search to find the best fitting source locations along the subducted slab in each successive time window. Our application of the method to the Tohoku-Oki earthquake resulted in artifact source locations at shallow depths near the trench caused by limited station coverage and noise effects. We then assumed various source node distributions along the plate, and found that the observed seismograms were most reasonably explained when assuming deep source nodes. This result suggests that the high-frequency seismic waves were radiated at deeper depths during the earthquake, a feature which is consistent with results obtained from teleseismic back-projection and strong-motion source model studies. We identified three high-frequency subevents, and compared them with the moment-rate function estimated from low-frequency seismograms. Our comparison indicated that no significant moment release occurred during the first high-frequency subevent and the largest moment-release pulse occurred almost simultaneously with the second high-frequency subevent. We speculated that the initial slow rupture propagated bilaterally from the hypocenter toward the land and trench. The landward subshear rupture propagation consisted of three successive high-frequency subevents. The trenchward propagation ruptured the strong asperity and released the largest moment near the trench.

Rapid Erosion Modeling in a Western Kenya Watershed using Visible Near Infrared Reflectance, Classification Tree Analysis and 137Cesium.

PubMed

deGraffenried, Jeff B; Shepherd, Keith D

2009-12-15

Human induced soil erosion has severe economic and environmental impacts throughout the world. It is more severe in the tropics than elsewhere and results in diminished food production and security. Kenya has limited arable land and 30 percent of the country experiences severe to very severe human induced soil degradation. The purpose of this research was to test visible near infrared diffuse reflectance spectroscopy (VNIR) as a tool for rapid assessment and benchmarking of soil condition and erosion severity class. The study was conducted in the Saiwa River watershed in the northern Rift Valley Province of western Kenya, a tropical highland area. Soil 137 Cs concentration was measured to validate spectrally derived erosion classes and establish the background levels for difference land use types. Results indicate VNIR could be used to accurately evaluate a large and diverse soil data set and predict soil erosion characteristics. Soil condition was spectrally assessed and modeled. Analysis of mean raw spectra indicated significant reflectance differences between soil erosion classes. The largest differences occurred between 1,350 and 1,950 nm with the largest separation occurring at 1,920 nm. Classification and Regression Tree (CART) analysis indicated that the spectral model had practical predictive success (72%) with Receiver Operating Characteristic (ROC) of 0.74. The change in 137 Cs concentrations supported the premise that VNIR is an effective tool for rapid screening of soil erosion condition.

Highway safety research : a national agenda : executive summary.

DOT National Transportation Integrated Search

2001-01-01

Motor vehicle-related injury and death is the nations largest public health problem. The economic costs to society : will approach $2 trillion and an even greater intangible human loss will occur to family and friends of the 33 million : victims. :...

Proactive and Reactive Stopping When Distracted: An Attentional Account

PubMed Central

2014-01-01

Performance in response inhibition paradigms is typically attributed to inhibitory control. Here we examined the idea that stopping may largely depend on the outcome of a sensory detection process. Subjects performed a speeded go task, but they were instructed to withhold their response when a visual stop signal was presented. The stop signal could occur in the center of the screen or in the periphery. On half of the trials, perceptual distractors were presented throughout the trial. We found that these perceptual distractors impaired stopping, especially when stop signals could occur in the periphery. Furthermore, the effect of the distractors on going was smallest in the central stop-signal condition, medium in a condition in which no signals could occur, and largest in the condition in which stop signals could occur in the periphery. The results show that an important component of stopping is finding a balance between ignoring irrelevant information in the environment and monitoring for the occurrence of occasional stop signals. These findings highlight the importance of sensory detection processes when stopping and could shed new light on a range of phenomena and findings in the response inhibition literature. PMID:24842070

Two new species of Euconnus (Rhomboconnus) in Peru and Bolivia (Coleoptera, Staphylinidae, Scydmaeninae).

PubMed

JaŁoszyŃski, PaweŁ

2018-01-25

To date, the subgenus Rhomboconnus Franz of Euconnus Thomson was represented by ten species known to occur in Venezuela, Panama and Ecuador. For the first time Rhomboconnus is reported to occur in Peru and Bolivia, and two new species are described: Euconnus wari sp. n. (Peru) and E. inkachakanus sp. n. (Bolivia). The latter species is the largest representative of Rhomboconnus, with body length exceeding 3 mm.

Structural origin of fractional Stokes-Einstein relation in glass-forming liquids

NASA Astrophysics Data System (ADS)

Pan, Shaopeng; Wu, Z. W.; Wang, W. H.; Li, M. Z.; Xu, Limei

2017-01-01

In many glass-forming liquids, fractional Stokes-Einstein relation (SER) is observed above the glass transition temperature. However, the origin of such phenomenon remains elusive. Using molecular dynamics simulations, we investigate the break- down of SER and the onset of fractional SER in a model of metallic glass-forming liquid. We find that SER breaks down when the size of the largest cluster consisting of trapped atoms starts to increase sharply at which the largest cluster spans half of the simulations box along one direction, and the fractional SER starts to follows when the largest cluster percolates the entire system and forms 3-dimentional network structures. Further analysis based on the percolation theory also confirms that percolation occurs at the onset of the fractional SER. Our results directly link the breakdown of the SER with structure inhomogeneity and onset of the fraction SER with percolation of largest clusters, thus provide a possible picture for the break- down of SER and onset of fractional SER in glass-forming liquids, which is is important for the understanding of the dynamic properties in glass-forming liquids.

Lexical influences on competing speech perception in younger, middle-aged, and older adults

PubMed Central

Helfer, Karen S.; Jesse, Alexandra

2015-01-01

The influence of lexical characteristics of words in to-be-attended and to-be-ignored speech streams was examined in a competing speech task. Older, middle-aged, and younger adults heard pairs of low-cloze probability sentences in which the frequency or neighborhood density of words was manipulated in either the target speech stream or the masking speech stream. All participants also completed a battery of cognitive measures. As expected, for all groups, target words that occur frequently or that are from sparse lexical neighborhoods were easier to recognize than words that are infrequent or from dense neighborhoods. Compared to other groups, these neighborhood density effects were largest for older adults; the frequency effect was largest for middle-aged adults. Lexical characteristics of words in the to-be-ignored speech stream also affected recognition of to-be-attended words, but only when overall performance was relatively good (that is, when younger participants listened to the speech streams at a more advantageous signal-to-noise ratio). For these listeners, to-be-ignored masker words from sparse neighborhoods interfered with recognition of target speech more than masker words from dense neighborhoods. Amount of hearing loss and cognitive abilities relating to attentional control modulated overall performance as well as the strength of lexical influences. PMID:26233036

Landslide-Generated Waves in a Dam Reservoir: The Effects of Landslide Rheology and Initial Submergence

NASA Astrophysics Data System (ADS)

Yavari Ramsheh, S.; Ataie-Ashtiani, B.

2017-12-01

Recent studies revealed that landslide-generated waves (LGWs) impose the largest tsunami hazard to our shorelines although earthquake-generated waves (EGWs) occur more often. Also, EGWs are commonly followed by a large number of landslide hazards. Dam reservoirs are more vulnerable to landslide events due to being located in mountainous areas. Accurate estimation of such hazards and their destructive consequences help authorities to reduce their risks by constructive measures. In this regard, a two-layer two-phase Coulomb mixture flow (2LCMFlow) model is applied to investigate the effects of landslide characteristics on LGWs for a real-sized simplification of the Maku dam reservoir, located in the North of Iran. A sensitivity analysis is performed on the role of landslide rheological and constitutive parameters and its initial submergence in LGW characteristics and formation patterns. The numerical results show that for a subaerial (SAL), a semi-submerged (SSL), and a submarine landslide (SML) with the same initial geometry, the SSLs can create the largest wave crest, up to 60% larger than SALs, for dense material. However, SMLs generally create the largest wave troughs and SALs travel the maximum runout distances beneath the water. Regarding the two-phase (solid-liquid) nature of the landslide, when interestial water is isolated from the water layer along the water/landslide interface, a LGW with up to 30% higher wave crest can be created. In this condition, increasing the pore water pressure within the granular layer results in up to 35% higher wave trough and 40% lower wave crest at the same time. These results signify the importance of appropriate description of two-phase nature and rheological behavior of landslides in accurate estimation of LGWs which demands further numerical, physical, and field studies about such phenomena.

A diagnostic approach to increase reusable dinnerware selection in a cafeteria.

PubMed

Manuel, Jennifer C; Sunseri, Mary Anne; Olson, Ryan; Scolari, Miranda

2007-01-01

The current project tested a diagnostic approach to selecting interventions to increase patron selection of reusable dinnerware in a cafeteria. An assessment survey, completed by a sample of 43 patrons, suggested that the primary causes of wasteful behavior were (a) environmental arrangement of dinnerware options and (b) competing motivational variables. A functional relation between environmental arrangement and reusable product selection was demonstrated in a reversal design. However, the largest effect occurred as function of a multicomponent intervention involving environmental arrangement, employee involvement, and personal spoken prompts with motivational signs. The results support the use of informant assessments when designing community interventions.

A Diagnostic Approach to Increase Reusable Dinnerware Selection in a Cafeteria

PubMed Central

Manuel, Jennifer C; Anne Sunseri, Mary; Olson, Ryan; Scolari, Miranda

2007-01-01

The current project tested a diagnostic approach to selecting interventions to increase patron selection of reusable dinnerware in a cafeteria. An assessment survey, completed by a sample of 43 patrons, suggested that the primary causes of wasteful behavior were (a) environmental arrangement of dinnerware options and (b) competing motivational variables. A functional relation between environmental arrangement and reusable product selection was demonstrated in a reversal design. However, the largest effect occurred as function of a multicomponent intervention involving environmental arrangement, employee involvement, and personal spoken prompts with motivational signs. The results support the use of informant assessments when designing community interventions. PMID:17624069

Association Between Cardiovascular and Intraocular Pressure Changes in a 14-day 6 deg Head Down Tilt (HDT) Bed Rest Study: Possible Implications in Retinal Anatomy

NASA Technical Reports Server (NTRS)

Cromwell, R. L.; Zanello, S. B.; Yarbough, P. O.; Ploutz-Snyder, R.; Taibbi, G.; Brewer, J. L.; Vizzeri, G.

2013-01-01

Mean IOP significantly increased while at 6deg HDT and returned towards pre-bed rest values upon leaving bed rest. While mean IOP increased during bed rest, it remained within the normal limits for subject safety. A diuretic shift and cardiovascular deconditioning occurs during in-bed rest, as expected. There was no demonstrable correlation between the largest change in IOP (pre/post) and cardiovascular measure changes (pre/post). Additional mixed effects linear regression modeling may reveal some subclinical physiological changes that might assist in describing the VIIP syndrome pathophysiology.

Temporal variation of the arterial pressure in healthy young people and its relation to geomagnetic activity in Mexico

NASA Astrophysics Data System (ADS)

Azcárate, T.; Mendoza, B.; Sánchez de la Peña, S.; Martínez, J. L.

2012-11-01

We present a study of the temporal behavior of the systolic (SBP) and diastolic (DBP) blood pressure for a sample of 51 normotensive, healthy volunteers, 18 men and 33 women with an average age of 19 years old in Mexico City, Mexico, during April and May, 2008. We divided the data by sex along the circadian rhythm. Three geomagnetic storms occurred during the studied time-span. The strongest one, a moderate storm, is attributed to a coronal hole border that reached the Earth. The ANOVA test applied to the strongest storm showed that even though we are dealing with a moderate geomagnetic storm, there are statistically significant responses of the blood pressure. The superposed epoch analysis during a three-day window around the strongest storm shows that on average the largest changes occurred for the SBP. Moreover, the SBP largest increases occurred two days before and one day after this storm, and women are the most sensitive group as they present larger SBP and DBP average changes than men. Finally, given the small size of the sample, we cannot generalize our results.

Consumer-mediated recycling and cascading trophic interactions.

PubMed

Leroux, Shawn J; Loreau, Michel

2010-07-01

Cascading trophic interactions mediated by consumers are complex phenomena, which encompass many direct and indirect effects. Nonetheless, most experiments and theory on the topic focus uniquely on the indirect, positive effects of predators on producers via regulation of herbivores. Empirical research in aquatic ecosystems, however, demonstrate that the indirect, positive effects of consumer-mediated recycling on primary producer stocks may be larger than the effects of herbivore regulation, particularly when predators have access to alternative prey. We derive an ecosystem model with both recipient- and donor-controlled trophic relationships to test the conditions of four hypotheses generated from recent empirical work on the role of consumer-mediated recycling in cascading trophic interactions. Our model predicts that predator regulation of herbivores will have larger, positive effects on producers than consumer-mediated recycling in most cases but that consumer-mediated recycling does generally have a positive effect on producer stocks. We demonstrate that herbivore recycling will have larger effects on producer biomass than predator recycling when turnover rates and recycling efficiencies are high and predators prefer local prey. In addition, predictions suggest that consumer-mediated recycling has the largest effects on primary producers when predators prefer allochthonous prey and predator attack rates are high. Finally, our model predicts that consumer-mediated recycling effects may not be largest when external nutrient loading is low. Our model predictions highlight predator and prey feeding relationships, turnover rates, and external nutrient loading rates as key determinants of the strength of cascading trophic interactions. We show that existing hypotheses from specific empirical systems do not occur under all conditions, which further exacerbates the need to consider a broad suite of mechanisms when investigating trophic cascades.

Reversible stress softening of collagen based networks from the jumbo squid mantle (Dosidicus gigas).

PubMed

Torres, F G; Troncoso, O P; Rivas, E R; Gomez, C G; Lopez, D

2014-04-01

Dosidicus gigas is the largest and one of the most abundant jumbo squids in the eastern Pacific Ocean. In this paper we have studied the muscle of the mantle of D. gigas (DGM). Morphological, thermal and rheological properties were assessed by means of atomic force microscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, differential scanning calorimetry, thermogravimetry and oscillatory rheometry. This study allowed us to assess the morphological and rheological properties of a collagen based network occurring in nature. The results showed that the DGM network displays a nonlinear effect called reversible stress softening (RSS) that has been previously described for other types of biological structures such as naturally occurring cellulose networks and actin networks. We propose that the RSS could play a key role on the way jumbo squids withstand hydrostatic pressure. The results presented here confirm that this phenomenon occurs in a wider number of materials than previously thought, all of them exhibiting different size scales as well as physical conformation. Copyright © 2013 Elsevier B.V. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zuidema, P; Chiu, C; Fairall, CW

Southern Africa is the world’s largest emitter of biomass-burning (BB) aerosols. Their westward transport over the remote southeast Atlantic Ocean colocates some of the largest atmospheric loadings of absorbing aerosol with the least examined of the Earth’s major subtropical stratocumulus decks. Global aerosol model results highlight that the largest positive top-of-atmosphere forcing in the world occurs in the southeast Atlantic, but this region exhibits large differences in magnitude and sign between reputable models, in part because of high variability in the underlying model cloud distributions. Many uncertainties contribute to the highly variable model radiation fields: the aging of shortwave-absorbing aerosolmore » during transport, how much of the aerosol mixes into the cloudy boundary layer, and how the low clouds adjust to smoke-radiation and smoke-cloud interactions. In addition, the ability of the BB aerosol to absorb shortwave radiation is known to vary seasonally as the fuel type on land changes.« less

Aftershocks and triggered events of the Great 1906 California earthquake

USGS Publications Warehouse

Meltzner, A.J.; Wald, D.J.

2003-01-01

The San Andreas fault is the longest fault in California and one of the longest strike-slip faults in the world, yet little is known about the aftershocks following the most recent great event on the San Andreas, the Mw 7.8 San Francisco earthquake on 18 April 1906. We conducted a study to locate and to estimate magnitudes for the largest aftershocks and triggered events of this earthquake. We examined existing catalogs and historical documents for the period April 1906 to December 1907, compiling data on the first 20 months of the aftershock sequence. We grouped felt reports temporally and assigned modified Mercalli intensities for the larger events based on the descriptions judged to be the most reliable. For onshore and near-shore events, a grid-search algorithm (derived from empirical analysis of modern earthquakes) was used to find the epicentral location and magnitude most consistent with the assigned intensities. For one event identified as far offshore, the event's intensity distribution was compared with those of modern events, in order to contrain the event's location and magnitude. The largest aftershock within the study period, an M ???6.7 event, occurred ???100 km west of Eureka on 23 April 1906. Although not within our study period, another M ???6.7 aftershock occurred near Cape Mendocino on 28 October 1909. Other significant aftershocks included an M ???5.6 event near San Juan Bautista on 17 May 1906 and an M ???6.3 event near Shelter Cove on 11 August 1907. An M ???4.9 aftershock occurred on the creeping segment of the San Andreas fault (southeast of the mainshock rupture) on 6 July 1906. The 1906 San Francisco earthquake also triggered events in southern California (including separate events in or near the Imperial Valley, the Pomona Valley, and Santa Monica Bay), in western Nevada, in southern central Oregon, and in western Arizona, all within 2 days of the mainshock. Of these trigerred events, the largest were an M ???6.1 earthquake near Brawley and an M ???5.0 event under or near Santa Monica Bay, 11.3 and 31.3 hr after the San Francisco mainshock, respectively. The western Arizona event is inferred to have been triggered dynamically. In general, the largest aftershocks occurred at the ends of the 1906 rupture or away from the rupture entirely; very few significant aftershocks occurred along the mainshock rupture itself. The total number of large aftershocks was less than predicted by a generic model based on typical California mainshock-aftershock statistics, and the 1906 sequence appears to have decayed more slowly than average California sequences. Similarities can be drawn between the 1906 aftershock sequence and that of the 1857 (Mw 7.9) San Andreas fault earthquake.

Chapter 21. Composite shrubs

Treesearch

E. Durant McArthur; Richard Stevens

2004-01-01

The sunflower family (Compositae or Asteraceae) is the largest family of flowering plants. Its many species occur around the world as annual and perennial herbs and as shrubs and trees (Benson 1957; Cronquist 1968; Wagenitz 1977). Three shrubby genera of the family-sagebrush (Artemisia), rabbitbrush (Chrysothamnus), and matchbrush...

Analysis of the Casson and Carreau-Yasuda non-Newtonian blood models in steady and oscillatory flows using the lattice Boltzmann method

NASA Astrophysics Data System (ADS)

Boyd, Joshua; Buick, James M.; Green, Simon

2007-09-01

The lattice Boltzmann method is modified to allow the simulation of non-Newtonian shear-dependent viscosity models. Casson and Carreau-Yasuda non-Newtonian blood viscosity models are implemented and are used to compare two-dimensional Newtonian and non-Newtonian flows in the context of simple steady flow and oscillatory flow in straight and curved pipe geometries. It is found that compared to analogous Newtonian flows, both the Casson and Carreau-Yasuda flows exhibit significant differences in the steady flow situation. In the straight pipe oscillatory flows, both models exhibit differences in velocity and shear, with the largest differences occurring at low Reynolds and Womersley numbers. Larger differences occur for the Casson model. In the curved pipe Carreau-Yasuda model, moderate differences are observed in the velocities in the central regions of the geometries, and the largest shear rate differences are observed near the geometry walls. These differences may be important for the study of atherosclerotic progression.

NASA's SDO Observes Largest Sunspot of the Solar Cycle

NASA Image and Video Library

2017-12-08

On Oct. 18, 2014, a sunspot rotated over the left side of the sun, and soon grew to be the largest active region seen in the current solar cycle, which began in 2008. Currently, the sunspot is almost 80,000 miles across -- ten Earth's could be laid across its diameter. Sunspots point to relatively cooler areas on the sun with intense and complex magnetic fields poking out through the sun's surface. Such areas can be the source of solar eruptions such as flares or coronal mass ejections. So far, this active region – labeled AR 12192 -- has produced several significant solar flares: an X-class flare on Oct. 19, an M-class flare on Oct. 21, and an X-class flare on Oct. 22, 2014. The largest sunspot on record occurred in 1947 and was almost three times as large as the current one. Active regions are more common at the moment as we are in what's called solar maximum, which is the peak of the sun's activity, occurring approximately every 11 years. Credit: NASA/SDO NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Rays as weapons.

PubMed

Vogel, H

2007-08-01

Ionizing radiation is being regarded as life threatening. Therefore, accidents in nuclear power plants are considered equal threatening as nuclear bomb explosions, and attacks with dirty bombs are thought as dangerous as nuclear weapon explosions. However, there are differences between a nuclear bomb explosion, the largest imaginable accident in a nuclear power plant, and an attack with a dirty bomb. It is intended to point them out. The processes are described, which damage in a nuclear bomb explosion, in the largest imaginable accident in a nuclear power plant, and in an attack with a dirty bomb. Their effects are compared with each other, i.e. explosion, heat, shock wave (blast), ionizing radiation, and fallout. In the center of the explosion of a nuclear bomb, the temperature rises to 100Mio degrees C, this induces damaging heat radiation and shock wave. In the largest imaginable accident in a nuclear power plant and in the conventional explosion of a dirty bomb, the temperature may rise up to 3000 degrees C, heat radiation and blast are limited to a short distance. In nuclear power plants, explosions due to oxyhydrogen gas or steam may occur. In nuclear explosions the dispersed radioactive material (fall out) consists mainly of isotopes with short half-life, in nuclear power plants and in dirty bomb attacks with longer half-life. The amount of fall out is comparable in nuclear bomb explosions with that in the largest imaginable accident in a nuclear power plant, it is smaller in attacks with dirty bombs. An explosion in a nuclear power plant even in the largest imaginable accident is not a nuclear explosion. In Hiroshima and Nagasaki, there were 200,000 victims nearly all by heat and blast, some 300 died by ionizing radiation. In Chernobyl, there have been less than 100 victims due to ionizing radiation up till now. A dirty bomb kills possibly with the explosion of conventional explosive, the dispersed radioactive material may damage individuals. The incorporation of irradiating substances may kill and be difficult to detect (Litvinenko). A new form of (government supported) terrorism/crime appears possible. The differences are important between a nuclear weapon explosion, the largest imaginable accident in a nuclear power plant, and an attack with a dirty bomb. Nuclear weapons kill by heat and blast; in the largest imaginable accident in a nuclear power plant, they are less strong and limited to the plant; an attack with a dirty bomb is as life threatening as an ("ordinary") bomb attack, dispersed radiating material may be a risk for individuals.

Test-retest reliability and practice effects of the Wechsler Memory Scale-III.

PubMed

Lo, Ada H Y; Humphreys, Michael; Byrne, Gerard J; Pachana, Nancy A

2012-09-01

Although serial administration of cognitive tests is increasingly common, there is a paucity of research on test-retest reliabilities and practice effects, both of which are important for evaluating changes in functioning. Reliability is generally conceptualized as involving short-lasting changes in performance. However, when repeated testing occurs over a period of years, there will be some longer lasting effects. The implications of these longer lasting effects and practice effects on reliability were examined in the context of repeated administrations of the Wechsler Memory Scale-III in 339 community-dwelling women aged 40-79 years over 2 to 7 years. The results showed that Logical Memory and Verbal Paired Associates subtests were consistently the most reliable subtests across the age cohorts. The magnitude of practice effects varied as a function of subtests and age. The largest practice effects were found in the youngest age cohort, especially on the Faces, Logical Memory, and Verbal Paired Associates subtests. ©2012 The British Psychological Society.

Effects of minute misregistrations of prefabricated markers for image-guided dental implant surgery: an analytical evaluation.

PubMed

Rußig, Lorenz L; Schulze, Ralf K W

2013-12-01

The goal of the present study was to develop a theoretical analysis of errors in implant position, which can occur owing to minute registration errors of a reference marker in a cone beam computed tomography volume when inserting an implant with a surgical stent. A virtual dental-arch model was created using anatomic data derived from the literature. Basic trigonometry was used to compute effects of defined minute registration errors of only voxel size. The errors occurring at the implant's neck and apex both in horizontal as in vertical direction were computed for mean ±95%-confidence intervals of jaw width and length and typical implant lengths (8, 10 and 12 mm). Largest errors occur in vertical direction for larger voxel sizes and for greater arch dimensions. For a 10 mm implant in the frontal region, these can amount to a mean of 0.716 mm (range: 0.201-1.533 mm). Horizontal errors at the neck are negligible, with a mean overall deviation of 0.009 mm (range: 0.001-0.034 mm). Errors increase with distance to the registration marker and voxel size and are affected by implant length. Our study shows that minute and realistic errors occurring in the automated registration of a reference object have an impact on the implant's position and angulation. These errors occur in the fundamental initial step in the long planning chain; thus, they are critical and should be made aware to users of these systems. © 2012 John Wiley & Sons A/S.

Lanzarote, Canary Islands

NASA Image and Video Library

2017-01-06

Lanzarote is the easternmost of the Canary Islands, 125 km off the coast of Africa, and is the fourth largest of the archipelago, with an area of 846 square kilometers. Like all of the Canary Islands, its volcanic origin dates to about 15 million years ago. The largest historic eruption occurred in the 1730s. The island was first recorded by Pliny the Elder, though it may have been originally settled by the Phoenicians (Wikipedia). The image was acquired 12 March 2015, covers an area of 50.5 by 55.1 km, and is located near 29 degrees north, 13.6 degrees west. http://photojournal.jpl.nasa.gov/catalog/PIA21284

Goldstrike Mine, Nevada

NASA Image and Video Library

2017-05-15

This image from NASA Terra spacecraft shows Goldstrike in northeast Nevada, the largest gold mine in North America. The mine complex, (including the Betze-Post-Screamer open-pit, and Meikle and Rodeo underground mines) is owned and operated by the world's largest gold mining company, Barrick Gold. Gold occurs as microscopically fine grains, with an average grade of 0.1 ounces per ton of ore. Estimates of reserves are as high as 35 million ounces of gold. The image was acquired September 25, 2010, covers an area of 15 by 15 km, and is located at 41 degrees north, 116.4 degrees west. https://photojournal.jpl.nasa.gov/catalog/PIA21665

Assessing the effect of land use change on catchment runoff by combined use of statistical tests and hydrological modelling: Case studies from Zimbabwe

NASA Astrophysics Data System (ADS)

Lørup, Jens Kristian; Refsgaard, Jens Christian; Mazvimavi, Dominic

1998-03-01

The purpose of this study was to identify and assess long-term impacts of land use change on catchment runoff in semi-arid Zimbabwe, based on analyses of long hydrological time series (25-50 years) from six medium-sized (200-1000 km 2) non-experimental rural catchments. A methodology combining common statistical methods with hydrological modelling was adopted in order to distinguish between the effects of climate variability and the effects of land use change. The hydrological model (NAM) was in general able to simulate the observed hydrographs very well during the reference period, thus providing a means to account for the effects of climate variability and hence strengthening the power of the subsequent statistical tests. In the test period the validated model was used to provide the runoff record which would have occurred in the absence of land use change. The analyses indicated a decrease in the annual runoff for most of the six catchments, with the largest changes occurring for catchments located within communal land, where large increases in population and agricultural intensity have taken place. However, the decrease was only statistically significant at the 5% level for one of the catchments.

Outbreak of acute hypoglycemic encephalopathy associated with litchi consumption, Muzaffarpur, India, 2014

USDA-ARS?s Scientific Manuscript database

Background: Seasonal outbreaks of an acute neurologic illness with high mortality among young children occur annually in Muzaffarpur, Bihar, the largest litchi (lychee) fruit cultivation region in India. A wide range of infectious and non-infectious etiologies, including an association with litchi...

Dengue Virus 1 Outbreak in Buenos Aires, Argentina, 2016.

PubMed

Tittarelli, Estefanía; Lusso, Silvina B; Goya, Stephanie; Rojo, Gabriel L; Natale, Mónica I; Viegas, Mariana; Mistchenko, Alicia S; Valinotto, Laura E

2017-10-01

The largest outbreak of dengue in Buenos Aires, Argentina, occurred during 2016. Phylogenetic, phylodynamic, and phylogeographic analyses of 82 samples from dengue patients revealed co-circulation of 2 genotype V dengue virus lineages, suggesting that this virus has become endemic to the Buenos Aires metropolitan area.

Air-Ocean Characteristics During the Impact of Typhoons on the Ocean in the Pacific (ITOP) Program

DTIC Science & Technology

2011-09-01

high. The largest analyzed and observed differences were found to occur in regions of TC- induced ocean changes. The significance of this comparison...and observed differences were found to occur in regions of TC- induced ocean changes. The significance of this comparison is the contribution to...gift for inducing calm into a stressful process. I would also like to thank CDR J. Dumas for his support and assistance as not only a second reader

Fast and slow spindles during the sleep slow oscillation: disparate coalescence and engagement in memory processing.

PubMed

Mölle, Matthias; Bergmann, Til O; Marshall, Lisa; Born, Jan

2011-10-01

Thalamo-cortical spindles driven by the up-state of neocortical slow (< 1 Hz) oscillations (SOs) represent a candidate mechanism of memory consolidation during sleep. We examined interactions between SOs and spindles in human slow wave sleep, focusing on the presumed existence of 2 kinds of spindles, i.e., slow frontocortical and fast centro-parietal spindles. Two experiments were performed in healthy humans (24.5 ± 0.9 y) investigating undisturbed sleep (Experiment I) and the effects of prior learning (word paired associates) vs. non-learning (Experiment II) on multichannel EEG recordings during sleep. Only fast spindles (12-15 Hz) were synchronized to the depolarizing SO up-state. Slow spindles (9-12 Hz) occurred preferentially at the transition into the SO down-state, i.e., during waning depolarization. Slow spindles also revealed a higher probability to follow rather than precede fast spindles. For sequences of individual SOs, fast spindle activity was largest for "initial" SOs, whereas SO amplitude and slow spindle activity were largest for succeeding SOs. Prior learning enhanced this pattern. The finding that fast and slow spindles occur at different times of the SO cycle points to disparate generating mechanisms for the 2 kinds of spindles. The reported temporal relationships during SO sequences suggest that fast spindles, driven by the SO up-state feed back to enhance the likelihood of succeeding SOs together with slow spindles. By enforcing such SO-spindle cycles, particularly after prior learning, fast spindles possibly play a key role in sleep-dependent memory processing.

Global change impacts on river ecosystems: A high-resolution watershed study of Ebro river metabolism.

PubMed

Val, Jonatan; Chinarro, David; Pino, María Rosa; Navarro, Enrique

2016-11-01

Global change is transforming freshwater ecosystems, mainly through changes in basin flow dynamics. This study assessed how the combination of climate change and human management of river flow impacts metabolism of the Ebro River (the largest river basin in Spain, 86,100km(2)), assessed as gross primary production-GPP-and ecosystem respiration-ER. In order to investigate the influence of global change on freshwater ecosystems, an analysis of trends and frequencies from 25 sampling sites of the Ebro river basin was conducted. For this purpose, we examined the effect of anthropogenic flow control on river metabolism with a Granger causality study; simultaneously, took into account the effects of climate change, a period of extraordinary drought (largest in past 140years). We identified periods of sudden flow changes resulting from both human management and global climate effects. From 1998 to 2012, the Ebro River basin was trending toward a more autotrophic condition indicated by P/R ratio. Particularly, the results show that floods that occurred after long periods of low flows had a dramatic impact on the respiration (i.e., mineralization) capacity of the river. This approach allowed for a detailed characterization of the relationships between river metabolism and drought impacts at the watershed level. These findings may allow for a better understanding of the ecological impacts provoked by flow management, thus contributing to maintain the health of freshwater communities and ecosystem services that rely on their integrity. Copyright © 2016 Elsevier B.V. All rights reserved.

Patient motion effects on the quantification of regional myocardial blood flow with dynamic PET imaging

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hunter, Chad R. R. N.; Kemp, Robert A. de, E-mail: RAdeKemp@ottawaheart.ca; Klein, Ran

Purpose: Patient motion is a common problem during dynamic positron emission tomography (PET) scans for quantification of myocardial blood flow (MBF). The purpose of this study was to quantify the prevalence of body motion in a clinical setting and evaluate with realistic phantoms the effects of motion on blood flow quantification, including CT attenuation correction (CTAC) artifacts that result from PET–CT misalignment. Methods: A cohort of 236 sequential patients was analyzed for patient motion under resting and peak stress conditions by two independent observers. The presence of motion, affected time-frames, and direction of motion was recorded; discrepancy between observers wasmore » resolved by consensus review. Based on these results, patient body motion effects on MBF quantification were characterized using the digital NURBS-based cardiac-torso phantom, with characteristic time activity curves (TACs) assigned to the heart wall (myocardium) and blood regions. Simulated projection data were corrected for attenuation and reconstructed using filtered back-projection. All simulations were performed without noise added, and a single CT image was used for attenuation correction and aligned to the early- or late-frame PET images. Results: In the patient cohort, mild motion of 0.5 ± 0.1 cm occurred in 24% and moderate motion of 1.0 ± 0.3 cm occurred in 38% of patients. Motion in the superior/inferior direction accounted for 45% of all detected motion, with 30% in the superior direction. Anterior/posterior motion was predominant (29%) in the posterior direction. Left/right motion occurred in 24% of cases, with similar proportions in the left and right directions. Computer simulation studies indicated that errors in MBF can approach 500% for scans with severe patient motion (up to 2 cm). The largest errors occurred when the heart wall was shifted left toward the adjacent lung region, resulting in a severe undercorrection for attenuation of the heart wall. Simulations also indicated that the magnitude of MBF errors resulting from motion in the superior/inferior and anterior/posterior directions was similar (up to 250%). Body motion effects were more detrimental for higher resolution PET imaging (2 vs 10 mm full-width at half-maximum), and for motion occurring during the mid-to-late time-frames. Motion correction of the reconstructed dynamic image series resulted in significant reduction in MBF errors, but did not account for the residual PET–CTAC misalignment artifacts. MBF bias was reduced further using global partial-volume correction, and using dynamic alignment of the PET projection data to the CT scan for accurate attenuation correction during image reconstruction. Conclusions: Patient body motion can produce MBF estimation errors up to 500%. To reduce these errors, new motion correction algorithms must be effective in identifying motion in the left/right direction, and in the mid-to-late time-frames, since these conditions produce the largest errors in MBF, particularly for high resolution PET imaging. Ideally, motion correction should be done before or during image reconstruction to eliminate PET-CTAC misalignment artifacts.« less

Ion accelerator system mounting design and operating characteristics for a 5 kW 30-cm xenon ion engine

NASA Technical Reports Server (NTRS)

Aston, Graeme; Brophy, John R.

1987-01-01

Results from a series of experiments to determine the effect of accelerator grid mount geometry on the performance of the J-series ion optics assembly are described. Three mounting schemes, two flexible and one rigid, are compared for their relative ion extraction capability over a range of total accelerating voltages. The largest ion beam current, for the maximum total voltage investigated, is shown to occur using one of the flexible grid mounting geometries. However, at lower total voltages and reduced engine input power levels, the original rigid J-series ion optics accelerator grid mounts result in marginally better grid system performance at the same cold interelectrode gap.

Overload and Underload Effects on the Fatigue Crack Growth Behavior of the 2024-T3 Aluminum Alloy

NASA Technical Reports Server (NTRS)

Dawicke, David S.

1997-01-01

Fatigue crack growth tests were conducted on 0.09 inch thick, 3.0 inch wide middle-crack tension specimens cut from sheets of 2024-T3 aluminum alloy. The tests were conducted using a load sequence that consisted of a single block of 2,500 cycles of constant amplitude loading followed by an overload/underload combination. The largest fatigue crack growth life occurred for the tests with the overload stress equal to 2 times the constant amplitude stress and the underload stress equal to the constant amplitude minimum stress. For the tests with compressive underloads, the fatigue crack growth life decreased with increasing compressive underload stress.

Achieving the American dream: facilitators and barriers to health and mental health for Latino immigrants.

PubMed

Shobe, Marcia A; Coffman, Maren J; Dmochowski, Jacek

2009-01-01

Latinos are the largest minority group in the U.S. For Latino immigrants, a shift in migration from larger to smaller cities has recently occurred; the Latino immigrant population in Charlotte, North Carolina, has increased by 634% since 1990. The extent to which immigrants can achieve health and well-being is often related to employment, healthcare access, and social support. This study explored the human, social, and financial capital circumstances of Latino immigrants new to Charlotte and examined the effects of different aspects of capital on health outcomes. Findings indicate that capital is significantly associated with functional status and depression. Implications for social work are discussed.

Use of glucose oxidase to improve refrigerated dough quality

USDA-ARS?s Scientific Manuscript database

Refrigerated dough encompasses a wide range of products including bread, rolls, pastries and pizza crust and is a very popular choice for consumers. Two of the largest problems that occur during refrigerated dough storage are dough syruping and loss of dough strength. The goal of this study was to e...

Repeated Acquisitions and Extinctions in Classical Conditioning of the Rabbit Nictitating Membrane Response

ERIC Educational Resources Information Center

Kehoe, E. James

2006-01-01

The rabbit nictitating membrane (NM) response underwent successive stages of acquisition and extinction training in both delay (Experiment 1) and trace (Experiment 2) classical conditioning. In both cases, successive acquisitions became progressively faster, although the largest, most reliable acceleration occurred between the first and second…

Bark beetles in a changing climate

Treesearch

John E. Lundquist; Barbara J. Bentz

2009-01-01

Over the past decade, native bark beetles (Coleoptera: Curculionidae) have killed billions of trees across millions of hectares of forest from Alaska to Mexico. Although bark beetle infestations are a regular force of natural change in forested ecosystems, several current outbreaks occurring simultaneously across western North America are the largest and most...

Intra- and interannual dynamics of dinoflagellate bloom species in the James River, an urban tidal estuary in Virginia, USA

NASA Astrophysics Data System (ADS)

Echevarria, M. A.; Mulholland, M. R.; Filippino, K.; Egerton, T.

2016-02-01

Algal blooms occur throughout the year in the tidal tributaries of Chesapeake Bay. The James River is the largest river in Virginia and third largest tributary of the Bay. Of the nearly 1500 species found in the estuary, two dinoflagellates; Heterocapsa triquetra and Cochlodinium polykrikoides have historically formed large seasonal algal blooms in spring and summer respectively, lasting several weeks to months annually. Additionally, the toxic dinoflagellate Alexandrium monilatum has emerged as an annual late summer bloom producer with increasing abundance in the region over the last nine years. These blooms have occurred in the lower James River, including meso- and polyhaline waters. Presented here are comparisons of the temporal and spatial extent and magnitude of these three dinoflagellate species over a two-year period (2014-2015). In 2014 dinoflagellate abundance was low compared to prior years. In contrast, massive spring and summer blooms occurred in 2015 with extended durations. In 2015, H. triquetra reached a maximum concentration of >84,000 cells/ml, with densities >103 cells/mL observed over a six week period, compared to no visible bloom the year before and a maximum of only 6200 cells/ml. Similarly in 2015, C. polykrikoides reached maximum cell densities of >41,000 cells/ml, with densities >103 cells/mL observed over a seven week period, compared to a maximum the year before of <11,000 cells/ml. A. monilatum reached a maximum of >7,500 cells/ml over a three week period in August 2015, with no bloom recorded in 2014. Multiple environmental parameters likely contributed to the interannual variability in bloom formation and duration. Temperature appeared to be a significant factor, with cooler than average surface water during the summer of 2014. In addition, the effect of prevailing wind patterns, precipitation, salinity, nutrient concentrations and sediment re-suspension were examined.

Comparing the November 2002 Denali and November 2001 Kunlun earthquakes

USGS Publications Warehouse

Bufe, C.G.

2004-01-01

Major strike-slip earthquakes recently occurred in Alaska on the central Denali fault (M 7.9) on 3 November 2002, and in Tibet on the central Kunlun fault (M 7.8) on 14 November 2001. Both earthquakes generated large surface waves with Ms [U.S. Geological Survey (USGS)] of 8.5 (Denali) and 8.0 (Kunlun). Each event occurred on an east-west-trending strike-slip fault situated near the northern boundary of an intense deformation zone that is characterized by lateral extrusion and rotation of crustal blocks. Each earthquake produced east-directed nearly unilateral ruptures that propagated 300 to 400 km. Maximum lateral surface offsets and maximum moment release occurred well beyond 100 km from the rupture initiation, with the events exhibiting by far the largest separations of USGS hypocenter and Harvard Moment Tensor Centroid (CMT) for strike-slip earthquakes in the 27-year CMT catalog. In each sequence, the largest aftershock was more than two orders of magnitude smaller than the mainshock. Regional moment release had been accelerating prior to the main shocks. The close proximity in space and time of the 1964 Prince William Sound and 2002 Denali earthquakes, relative to their rupture lengths and estimated return times, suggests that these events may be part of a recurrent cluster in the vicinity of a complex plate boundary.

Do resource utilization and clinical measures still vary across dialysis chains after controlling for the local practices of facilities and physicians?

PubMed

Hirth, Richard A; Turenne, Marc N; Wheeler, John R C; Ma, Yu; Messana, Joseph M

2010-08-01

Because of adverse survival effects, anemia management and financial incentives to increase doses of erythropoiesis-stimulating agents (ESAs) have been controversial. Prior studies showed more aggressive anemia management in dialysis facilities owned by for-profit chains, but have been criticized for not accounting for practices of individual physicians and facilities. To improve understanding of how dialysis practices and resource utilization are influenced by physicians, facilities, and chains. Mixed models with chain fixed effects and facility and physician random effects. Medicare hemodialysis patients in 2004. A total of 234,158 patients, 3995 facilities, 4838 physicians, and 7 chain classifications were included. Spending per session for dialysis-related services billed separately from the dialysis treatment and for ESAs. Achievement of hematocrit (HCT) and urea reduction ratio (URR) targets. Of the 4 largest for-profit chains, 3 had higher resource use than independents, with differences up to $17.92 higher ESA/session. Utilization was positively associated with achieving target HCT. Despite incurring lower costs, patients treated by a large nonprofit chain were as likely as patients of independents to achieve the HCT target. The largest chains were more likely than independents to achieve the URR target. Substantial variation occurred across physicians and facilities, and adjustment for chain only modestly decreased this variation. Chains' methods of influencing practices were not directly observed. Chains appear to have the ability to implement protocols that shift practices, but not the ability to substantially reduce local variation. Assertions that chain effects found by earlier studies were spurious are not supported.

Expertise effects in the Moses illusion: detecting contradictions with stored knowledge.

PubMed

Cantor, Allison D; Marsh, Elizabeth J

2017-02-01

People frequently miss contradictions with stored knowledge; for example, readers often fail to notice any problem with a reference to the Atlantic as the largest ocean. Critically, such effects occur even though participants later demonstrate knowing the Pacific is the largest ocean (the Moses Illusion) [Erickson, T. D., & Mattson, M. E. (1981). From words to meaning: A semantic illusion. Journal of Verbal Learning & Verbal Behavior, 20, 540-551]. We investigated whether such oversights disappear when erroneous references contradict information in one's expert domain, material which likely has been encountered many times and is particularly well-known. Biology and history graduate students monitored for errors while answering biology and history questions containing erroneous presuppositions ("In what US state were the forty-niners searching for oil?"). Expertise helped: participants were less susceptible to the illusion and less likely to later reproduce errors in their expert domain. However, expertise did not eliminate the illusion, even when errors were bolded and underlined, meaning that it was unlikely that people simply skipped over errors. The results support claims that people often use heuristics to judge truth, as opposed to directly retrieving information from memory, likely because such heuristics are adaptive and often lead to the correct answer. Even experts sometimes use such shortcuts, suggesting that overlearned and accessible knowledge does not guarantee retrieval of that information.

Mapping the MMPI-2-RF Substantive Scales Onto Internalizing, Externalizing, and Thought Dysfunction Dimensions in a Forensic Inpatient Setting.

PubMed

Romero, Isabella E; Toorabally, Nasreen; Burchett, Danielle; Tarescavage, Anthony M; Glassmire, David M

2017-01-01

Contemporary models of psychopathology-encompassing internalizing, externalizing, and thought dysfunction factors-have gained significant support. Although research indicates the Minnesota Multiphasic Personality Inventory-2 Restructured Form (MMPI-2-RF; Ben-Porath & Tellegen, 2008 /2011) measures these domains of psychopathology, this study addresses extant limitations in MMPI-2-RF diagnostic validity research by examining associations between all MMPI-2-RF substantive scales and broad dichotomous indicators of internalizing, externalizing, and thought dysfunction diagnoses in a sample of 1,110 forensic inpatients. Comparing those with and without internalizing diagnoses, notable effects were observed for Negative Emotionality/Neuroticism-Revised (NEGE-r), Emotional/Internalizing Dysfunction (EID), Dysfunctional Negative Emotions (RC7), Demoralization (RCd), and several other internalizing and somatic/cognitive scales. Comparing those with and without thought dysfunction diagnoses, the largest hypothesized differences occurred for Thought Dysfunction (THD), Aberrant Experiences (RC8), and Psychoticism-Revised (PSYC-r), although unanticipated differences were observed on internalizing and interpersonal scales, likely reflecting the high prevalence of internalizing dysfunction in forensic inpatients not experiencing thought dysfunction. Comparing those with and without externalizing diagnoses, the largest effects were for Substance Abuse (SUB), Antisocial Behavior (RC4), Behavioral/Externalizing Dysfunction (BXD), Juvenile Conduct Problems (JCP), and Disconstraint-Revised (DISC-r). Multivariate models evidenced similar results. Findings support the construct validity of MMPI-2-RF scales as measures of internalizing, thought, and externalizing dysfunction.

Effects of Streptococcus bovis Isolated from Bovine Rumen on the Fermentation Characteristics and Nutritive Value of Tanzania Grass Silage

PubMed Central

Zanine, Anderson de Moura; Bonelli, Emerson Alencar; de Souza, Alexandre Lima; Ferreira, Daniele de Jesus; Santos, Edson Mauro; Ribeiro, Marinaldo Divino; Geron, Luiz Juliano Valério; Pinho, Ricardo Martins Araujo

2016-01-01

This study aimed to evaluate the effects of Streptococcus bovis on the fermentation characteristics and nutritive value of Tanzania grass silage. Tanzania grass was chopped and left untreated (U) or treated with Streptococcus bovis JB1 at 1 × 106 colony-forming units per gram (cfu/g) of fresh forage or Streptococcus bovis HC5 at 1 × 106 cfu/g of fresh forage and packed into sixtuplicate laboratory silos. The largest number of enterobacteria, molds and yeast (M&Y) occurred in untreated silages and the smallest populations of enterobacteria and M&Y and the largest numbers of lactic acid bacteria (LAB), at 9.81 and 9.87 log cfu/g, were observed in Streptococcus bovis JB1 and HC5, respectively (P < 0.05). Silages treated with JB1 and HC5 had lower (P < 0.05) silage pHs and concentrations of ammoniacal nitrogen (NH3-N) than untreated silages. The application of Streptococcus bovis JB1 and HC5 resulted in fewer losses through gases and effluents (P < 0.05), which resulted in greater dry matter recovery (DMR) and crude protein recovery (CPR) (P < 0.05). Streptococcus bovis JB1 and HC5 improved the fermentative profile and increased the concentration of crude protein and DMR and CPR in Tanzania grass silage. PMID:27073806

Support surface related changes in feedforward and feedback control of standing posture

PubMed Central

Mohapatra, Sambit; Kukkar, Komal K.; Aruin, Alexander S.

2013-01-01

The aim of the study was to investigate the effect of different support surfaces on feedforward and feedback components of postural control. Nine healthy subjects were exposed to external perturbations applied to their shoulders while standing on a rigid platform, foam, and wobble board with eyes open or closed. Electrical activity of nine trunk and leg muscles and displacements of the center of pressure were recorded and analyzed during the time frames typical of feedforward and feedback postural adjustments. Feedforward control of posture was characterized by earlier activation of anterior muscles when the subjects stood on foam compared to a wobble board or a firm surface. In addition, the magnitude of feedforward muscle activity was the largest when the foam was used. During the feedback control, anterior muscles were activated prior to posterior muscles irrespective of the nature of surface. Moreover, the largest muscle activity was seen when the supporting surface was foam. Maximum CoP displacement occurred when subjects were standing on a rigid surface. Altering support surface affects both feedforward and feedback components of postural control. This information should be taken into consideration in planning rehabilitation interventions geared towards improvement of balance. PMID:24268589

Support surface related changes in feedforward and feedback control of standing posture.

PubMed

Mohapatra, Sambit; Kukkar, Komal K; Aruin, Alexander S

2014-02-01

The aim of the study was to investigate the effect of different support surfaces on feedforward and feedback components of postural control. Nine healthy subjects were exposed to external perturbations applied to their shoulders while standing on a rigid platform, foam, and wobble board with eyes open or closed. Electrical activity of nine trunk and leg muscles and displacements of the center of pressure were recorded and analyzed during the time frames typical of feedforward and feedback postural adjustments. Feedforward control of posture was characterized by earlier activation of anterior muscles when the subjects stood on foam compared to a wobble board or a firm surface. In addition, the magnitude of feedforward muscle activity was the largest when the foam was used. During the feedback control, anterior muscles were activated prior to posterior muscles irrespective of the nature of surface. Moreover, the largest muscle activity was seen when the supporting surface was foam. Maximum CoP displacement occurred when subjects were standing on a rigid surface. Altering support surface affects both feedforward and feedback components of postural control. This information should be taken into consideration in planning rehabilitation interventions geared towards improvement of balance. Copyright © 2013 Elsevier Ltd. All rights reserved.

Small volcanic edifices and volcanism in the plains of Venus

NASA Technical Reports Server (NTRS)

Guest, John E.; Bulmer, Mark H.; Aubele, Jayne; Beratan, Kathi; Greeley, Ronald; Head, James W.; Michaels, Gregory; Weitz, Catherine; Wiles, Charles

1992-01-01

The different types of eruption that have occurred over time in the Venusian plains are considered. The most extensive volcanic units consist of flood lavas, the largest of which have volumes of the order of thousands of cubic kilometers. They are inferred to have erupted at high effusion rates, and they exhibit a range of radar backscatter characteristics indicating different surface textures and ages. Small edifices on the plains occur mainly in clusters associated with fracture belts. The majority are shield volcanos that may be up to a few tens of kilometers across but are generally 10 km or less in diameter. Volcanic domes have diameters up to several tens of kilometers and volumes of the order of 100 cu cm. These are interpreted as being constructed of lava erupted with a relatively high effective viscosity and thus possibly composed of more silicic lava. For many domes, the flanks were unstable during and after eruption and experienced gravity sliding that produced steep scalloped outer margins.

Period Variation in BW Vulpeculae (Abstract)

NASA Astrophysics Data System (ADS)

Cowall, D. E.; Odell, A. P.

2018-06-01

(Abstract only) BW Vulpeculae (BW Vul) has the largest amplitude of the beta Cephei stars. An observing campaign on this star using the AAVSOnetís Bright Star Monitor (BSM) telescopes was begun in December of 2015 and has yielded 66 nights of observations to date. A period analysis will be presented using the BSM data set in combination with unpublished data from the Lowell Observatory. Over almost 80 years of observations, BW Vul has closely followed a parabolic ephemeris (period increasing by 2.4 seconds/century) plus a light-travel-time effect. This parabola with excursions on either side also could be viewed as a sequence of straight lines (constant period) with abrupt period increases. The first paradigm predicted a necessary change in slope around 2004, which did not occur. Instead, the period decreased abruptly in 2009. That maximum occurred 250 minutes early compared to the first paradigm, and about 25 minutes early compared to the straight-line paradigm from 1982ñ2009.

Pediatric maxillofacial fractures.

PubMed

Spring, P M; Cote, D N

1996-05-01

Maxillofacial trauma in the pediatric population is a relatively infrequent occurrence. Studies have demonstrated consistently that 5% of all facial fractures occur in children. The low percentage of facial fractures in this age group has been attributed, in part, to the lack of full pneumatization of the sinuses until later in childhood. Review of the literature indicates that boys are more commonly affected than girls and that the majority of pediatric facial fractures occur in children between 6 and 12 years of age. Motor vehicle accidents, falls, and blunt trauma are responsible for the largest number of pediatric facial fractures. The most common site of facial fracture is the nose and dentoalveolan complex, followed by the mandible, orbit, and midface in most pediatric cohorts. Management of the mandible is often conservative owing to the high percentage of isolated condylar fractures in children. Open reduction and internal fixation of pediatric facial fractures is indicated in complex mandible, midface, and orbital fractures. The effect of rigid fixation on facial skeleton growth is not completely understood.

Investigation of shipping accident injury severity and mortality.

PubMed

Weng, Jinxian; Yang, Dong

2015-03-01

Shipping movements are operated in a complex and high-risk environment. Fatal shipping accidents are the nightmares of seafarers. With ten years' worldwide ship accident data, this study develops a binary logistic regression model and a zero-truncated binomial regression model to predict the probability of fatal shipping accidents and corresponding mortalities. The model results show that both the probability of fatal accidents and mortalities are greater for collision, fire/explosion, contact, grounding, sinking accidents occurred in adverse weather conditions and darkness conditions. Sinking has the largest effects on the increment of fatal accident probability and mortalities. The results also show that the bigger number of mortalities is associated with shipping accidents occurred far away from the coastal area/harbor/port. In addition, cruise ships are found to have more mortalities than non-cruise ships. The results of this study are beneficial for policy-makers in proposing efficient strategies to prevent fatal shipping accidents. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effect of vibration amplitude on vapor cavitation in journal bearings

NASA Astrophysics Data System (ADS)

Brewe, D. E.; Jacobson, B. O.

Computational movies were used to analyze the formation and collapse of vapor cavitation bubbles in a submerged journal bearing. The effect of vibration amplitude on vapor cavitation was studied for a journal undergoing circular whirl. The boundary conditions were implemented using Elrod's algorithm, which conserves mass flow through the cavitation bubble as well as through the oil-film region of the bearing. The vibration amplitudes for the different cases studied resulted in maximum eccentricity ratios ranging from 0.4 to 0.9. The minimum eccentricity ratio reached in each case was 0.1. For the least vibration amplitude studied in which the eccentricity ratio varied between 0.1 and 0.4, no vapor cavitation occurred. The largest vibration amplitude (i.e., eccentricity ratios of 0.1 to 0.9) resulted in vapor cavitation present 76 percent of one complete orbit.

The O'Connor cinch revisited.

PubMed Central

Williams, A. T.; Metz, H. S.; Jampolsky, A.

1978-01-01

The modified O'Connor cinch operation is a useful, but little used, adjustable resection operation. For increased understanding of its shortening and adjustment characteristics, a standard cinch was performed in animals and patients with strabismus. Animal studies showed that, as each strand of the cinch was removed, a small, relatively equal release of the cinch effect occurred. Measurement of the shortening obtained in patients with strabismus showed a consistent resection effect of about 4 mm. Review of 17 cases in which the cinch was used as part of the surgical treatment showed the technique to be adjustable by reducing the overcorrection in 6 cases. Ten to 20 prism dioptres of reduction in the deviation was obtained with adjustment of the cinch on the first postoperative day. All 17 cases had satisfactory adjustment. The largest residual deviation was 12 prism dioptres. Images PMID:718816

Dynamic contact guidance of migrating cells

NASA Astrophysics Data System (ADS)

Losert, Wolfgang; Sun, Xiaoyu; Guven, Can; Driscoll, Meghan; Fourkas, John

2014-03-01

We investigate the effects of nanotopographical surfaces on the cell migration and cell shape dynamics of the amoeba Dictyostelium discoideum. Amoeboid motion exhibits significant contact guidance along surfaces with nanoscale ridges or grooves. We show quantitatively that nanoridges spaced 1.5 μm apart exhibit the greatest contact guidance efficiency. Using principal component analysis, we characterize the dynamics of the cell shape modulated by the coupling between the cell membrane and ridges. We show that motion parallel to the ridges is enhanced, while the turning, at the largest spatial scales, is suppressed. Since protrusion dynamics are principally governed by actin dynamics, we imaged the actin polymerization of cells on ridges. We found that actin polymerization occurs preferentially along nanoridges in a ``monorail'' like fashion. The ridges then provide us with a tool to study actin dynamics in an effectively reduced dimensional system.

Effect of vibration amplitude on vapor cavitation in journal bearings

NASA Technical Reports Server (NTRS)

Brewe, D. E.; Jacobson, B. O.

1986-01-01

Computational movies were used to analyze the formation and collapse of vapor cavitation bubbles in a submerged journal bearing. The effect of vibration amplitude on vapor cavitation was studied for a journal undergoing circular whirl. The boundary conditions were implemented using Elrod's algorithm, which conserves mass flow through the cavitation bubble as well as through the oil-film region of the bearing. The vibration amplitudes for the different cases studied resulted in maximum eccentricity ratios ranging from 0.4 to 0.9. The minimum eccentricity ratio reached in each case was 0.1. For the least vibration amplitude studied in which the eccentricity ratio varied between 0.1 and 0.4, no vapor cavitation occurred. The largest vibration amplitude (i.e., eccentricity ratios of 0.1 to 0.9) resulted in vapor cavitation present 76 percent of one complete orbit.

Management of the potato cyst nematode (Globodera pallida) with bio-fumigants/stimulants.

PubMed

Martin, T J G; Turner, S J; Fleming, C C

2007-01-01

Field trials evaluated the effect of four plant-based bio-fumigants/stimulants on population levels of G. pallida and the resulting potato yields and quality. Three formulations contained seaweed biostimulants (Algifol, Nutridip and Metastim) and one bio-fumigant containing mustard and chilli pepper extracts (Dazitol). These were compared with the fumigant nematicide Nemathorin and untreated control plots. The effect of G. pallida on growing potato crops was assessed by recording haulm characteristics which indicated that the nematicide treatment gave most protection. Levels of PCN juveniles and migratory nematodes were assessed during the trial. Plots treated with Nemathorin and Dazitol had fewest PCN, whilst the highest number of migratory nematodes occurred in fallow plots. Sixteen weeks after planting the nematicide treatment produced highest yield and tuber numbers. Dazitol treatment produced a lower yield but the largest tubers.

The Maupin, Oregon Earthquake Swarm

NASA Astrophysics Data System (ADS)

Braunmiller, J.; Williams, M.; Trehu, A. M.; Nabelek, J.

2008-12-01

The area near Maupin, Oregon has experienced over 300 earthquakes since December 2006. The events, located by the Pacific Northwest Seismic Network (PNSN), occurred ~10 km SE of the town in central Oregon and ~50 km E-SE of Mount Hood. The temporal event pattern and lack of a distinct main shock are characteristic of an earthquake swarm with the event-size distribution indicating a low b-value similar to other non-volcanic swarms. Locations show a NW-SE trending, ~4x3 km cluster at apparent depths of 12-24 km. The largest events (Mw=3.8 and 3.9) on March 1, 2007 and July 14, 2008 occurred more than one year apart; 11 other events had a magnitude of 3 or greater. The larger events were felt locally. During the first 14 months EarthScope USArray seismic stations surrounded the swarm, providing a unique high-quality dataset. Waveform similarity at the closest USArray site G06A indicates hypocenters are much tighter than suggested by the PNSN distribution. Moment tensor inversion reveals nearly identical double- couple strike-slip mechanisms on a plane striking ~15° NW for the three largest 2007 events and the July 2008 event. The April 2008 Mw=3.3 event is rotated ~10° clockwise consistent with slight changes of G06A three-component waveforms relative to the other events. Preferred centroid depths are in the 15-20 km range. Historically, seismicity in the Pacific Northwest east of the Cascades is characterized by sporadic bursts of clustered seismicity with occasional M=6 earthquakes. The largest instrumentally recorded earthquake near Maupin (Mw=4.6) occurred 1976. An earlier swarm was observed 1987, but since then only ~2 events/yr occurred until the current swarm. In spite of recurrent seismicity, exposed surface rocks near Maupin are undeformed lava flows of the Columbia River Basalt Group and older John Day volcanics. The geologic map of Oregon shows a NW-trending dip slip fault near the epicenter area, inconsistent with moment tensor solutions. The cause for the swarm is currently unknown with hypotheses ranging from magmatic or fluid motion in the crust to tectonic activity along a weakly coupled microplate boundary.

Terpenoids as potential chemopreventive and therapeutic agents in liver cancer

PubMed Central

Thoppil, Roslin J; Bishayee, Anupam

2011-01-01

Despite significant advances in medicine, liver cancer, predominantly hepatocellular carcinoma remains a major cause of death in the United States as well as the rest of the world. As limited treatment options are currently available to patients with liver cancer, novel preventive control and effective therapeutic approaches are considered to be reasonable and decisive measures to combat this disease. Several naturally occurring dietary and non-dietary phytochemicals have shown enormous potential in the prevention and treatment of several cancers, especially those of the gastrointestinal tract. Terpenoids, the largest group of phytochemicals, traditionally used for medicinal purposes in India and China, are currently being explored as anticancer agents in clinical trials. Terpenoids (also called “isoprenoids”) are secondary metabolites occurring in most organisms, particularly plants. More than 40 000 individual terpenoids are known to exist in nature with new compounds being discovered every year. A large number of terpenoids exhibit cytotoxicity against a variety of tumor cells and cancer preventive as well as anticancer efficacy in preclinical animal models. This review critically examines the potential role of naturally occurring terpenoids, from diverse origins, in the chemoprevention and treatment of liver tumors. Both in vitro and in vivo effects of these agents and related cellular and molecular mechanisms are highlighted. Potential challenges and future directions involved in the advancement of these promising natural compounds in the chemoprevention and therapy of human liver cancer are also discussed. PMID:21969877

Hollow form as a function of boulder size in the Valley and Ridge province, southwestern Virginia

NASA Astrophysics Data System (ADS)

Mills, Hugh H.

1989-07-01

Dells (hollows) that corrugate the antidip slopes of strike-ridge mountains in the Valley and Ridge province of southwestern Virginia vary greatly in cross-section form. This form is a function not of the underlying bedrock, but of the size and durability of boulders supplied to slopes by sandstones capping the strike ridge. Where the largest boulders are smaller than about 0.5 m in intermediate diameter, deep V-shaped dells occur. Where the largest boulders are larger than about 1.0 m, dells are shallow and U-shaped. Boulder size apparently determines the type of erosional processes that predominate in the development of the dells, and thereby dell form. Where boulder size is sufficiently small, running water is the dominant process and incises V-shaped dells. Where boulders are so large that even the largest floods cannot move them, the dell floor is armored and fluvial incision is greatly reduced. The evolution of such dells is dominated by debris flows that have recurrence intervals measured in millenia and by lateral fluvial erosion along the margins of the bouldery dell fill, both of which tend to produce shallow, U-shaped dells. Some evidence for the armoring effect of large boulders was obtained by applying a technique developed for reconstructing flash-flood peaks from boulder deposits. This procedure indicates that boulders in the V-shaped dells could be transported by high but plausible water flows, whereas movement of boulders in the U-shaped dells would require implausibly high flows.

Thermo-Oxidative Stability of Graphite/PMR-15 Composites: Effect of Fiber Surface Modification on Composite Shear Properties

NASA Technical Reports Server (NTRS)

Madhukar, Madhu S.; Bowles, Kenneth J.; Papadopolous, Demetrios S.

1994-01-01

Experiments were conducted to establish a correlation between the weight loss of a polyimide (PMR- 15) matrix and graphite fibers and the in-plane shear properties of their unidirectional composites subjected to different isothermal aging times up to 1000 hr at 316 C. The role of fiber surface treatment on the composite degradation during the thermo-oxidative aging was investigated by using A4 graphite fibers with three surface modifications: untreated (AU-4), surface treated (AS-4), and surface treated and sized with an epoxy-compatible sizing (AS-4G). The weight loss of the matrix fibers, and composites was determined during the aging. The effect of thermal aging was seen in all the fiber samples in terms of weight loss and reduction in fiber diameter. Calculated values of weight loss fluxes for different surfaces of rectangular unidirectional composite plates showed that the largest weight loss occurred at those cut surfaces where fibers were perpendicular to the surface. Consequently, the largest amount of damage was also noted on these cut surfaces. Optical observation of the neat matrix and composite plates subjected to different aging times revealed that the degradation (such as matrix microcracking and void growth) occurred in a thin surface layer near the specimen edges. The in-plane shear modulus of the composites was unaffected by the fiber surface treatment and the thermal aging. The shear strength of the composites with the untreated fibers was the lowest and it decreased with aging. A fracture surface examination of the composites with untreated fibers suggested that the weak interface allowed the oxidation reaction to proceed along the interface and thus expose the inner material to further oxidation. The results indicated that the fiber-matrix interface affected the composite degradation process during its thermal aging and that the the weak interface accelerated the composite degradation.

Response of Rocky Mountain elk (Cervus elaphus) to wind-power development

USGS Publications Warehouse

Walter, W. David; Leslie, David M.; Jenks, J.A.

2006-01-01

Wind-power development is occurring throughout North America, but its effects on mammals are largely unexplored. Our objective was to determine response (i.e., home-range, diet quality) of Rocky Mountain elk (Cervus elaphus) to wind-power development in southwestern Oklahoma. Ten elk were radiocollared in an area of wind-power development on 31 March 2003 and were relocated bi-weekly through March 2005. Wind-power construction was initiated on 1 June 2003 and was completed by December 2003 with 45 active turbines. The largest composite home range sizes (>80 km2) occurred April-June and September, regardless of the status of wind-power facility development. The smallest home range sizes (<50 km2) typically occurred in October-February when elk aggregated to forage on winter wheat. No elk left the study site during the study and elk freely crossed the gravel roads used to access the wind-power facility. Carbon and nitrogen isotopes and percent nitrogen in feces suggested that wind-power development did not affect nutrition of elk during construction. Although disturbance and loss of some grassland habitat was apparent, elk were not adversely affected by wind-power development as determined by home range and dietary quality.

[Clinical view of toxoplasmosis in children--personal observations].

PubMed

Czarnecka-Rudnik, D; Stanek-Bazylko, F

1997-05-01

In this work we presented our own experience with recognized and treated toxoplasmosis among children. Treated cases were observed over several years afterwards. We analyzed the frequency and character of clinical changes, evaluated the validity of serological screening and the effectiveness of treatment. The largest age group treated were children 13 months to 5 years old. 13 children had the congenital and 12 the acquired form. The most cases occurred in the nodal, ocular and ocular-cranial forms. Thus, the most common symptoms were enlarged lymphatic nodes, strabismus, febrile seizures, intracranial calcifications. In the acquired forms of the illness a distinct correlation between treatment and the decrease antibody levels, the clinical pictures showed stagnation. The fall in antibody levels occurred earlier with intermediate immunofluorescence than with ELISA method. Among 20 children associated 30-day treatment was implemented (Daraprim, Rovamycine, Biseptol), among 4 with Fansidar and Rovamycine for 2-3 weeks. Few complications occurred at the end of or after treatment and did not require treatment/intervention. Usually it was leukopenia and thrombocytopenia. Long time observation allows to state that both therapeutic models prevent renewal of illness and can be recommended for further use.

A molecular genetic linkage map identifying the St and H sub-genomes of Elymus wheatgrass (Poaceae: Triticeae)

USDA-ARS?s Scientific Manuscript database

Elymus L. is the largest and most complex genus in the Triticeae with approximately 150 polyploid perennial grass species occurring worldwide. We report here the first genetic linkage map for Elymus. Backcross mapping populations were created by crossing caespitose Elymus wawawaiensis (EW) (Snake ...

Phytophthora megakarya, a causal agent of black pod rot in Africa

USDA-ARS?s Scientific Manuscript database

In most parts of the world where Theobroma cacao is grown, Phytophthora palmivora is the major concern for causing black pod rot (BPR). Phytophthora megakarya, on the other hand, occurs only in Africa, but represents a major threat to cacao production, the countries of West Africa being the largest ...

Addition of glucose oxidase for the improvement of refrigerated dough quality

USDA-ARS?s Scientific Manuscript database

Refrigerated dough encompasses a wide range of products and is a very popular choice for consumers. Two of the largest problems that occur during refrigerated dough storage are dough syruping and loss of dough strength. The goal of this study was to evaluate glucose oxidase as an additive to refri...

Temporal changes to fire risk in dissimilar WUI communities

Treesearch

N. C. Leyshon; C. A. Dicus; D. B. Sapsis

2015-01-01

Despite increasing proportions of governmental budgets allocated to fire suppression resources, wildfires annually destroy great numbers of homes and critical infrastructure in the wildland-urban interface (WUI). Since 2002, the largest fires in the histories of California, Arizona, Colorado, New Mexico, Utah, Oregon, and Texas have occurred in spite of increased fire...

The Sundarbans: a unique wilderness of the world

Treesearch

Laskar Muqsudur Rahman

2000-01-01

The Sundarbans, natural mangrove forests of Bangladesh covers an area of 577,000 ha. It is the largest single tract of mangrove forest in the world. The members of the family Rhizophoracae do not dominate the tree vegetation of the Sundarbans. Heritiera fomes and Excoecaria agallocha are the two most extensively occurring tree...

Large Second-Harmonic Response of C60 Thin Films

DTIC Science & Technology

1992-04-01

temperature; the largest value occurred at a nominal temperature of 140’C where X"’ is ten times larger than the room temperature value. 14. SU8 )ECT TERMS 1S...optical chromatography.’ The purity was examined by Raman. IR materials based upon conjugated-carbon- polymers charac- absorption, high-performance liquid

US Research on Wildland Fires??…with a Focus on EPA’s Efforts

EPA Science Inventory

The United States spends more than $1 billion every year to fight wildfires. According to National Interagency Fire Center data, of the 10 years with the largest acreage burned, nine have occurred since 2000 (as of 2012). This period coincides with many of the warmest years on re...

Promoting Sustainable Economic Growth in Mexico (Fact Sheet)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Watson, A.; Butheau, M.; Sandor, D.

2013-11-01

Mexico is the second largest economy in Latin America, with rapid growth occurring in the industrial and services sectors. A forward-thinking country on climate change, the nation recognizes that the threat of higher temperatures, changes in precipitation patterns, and more frequent weather-related disasters could pose a substantial risk to its expanding economy.

Contributions to the anatomy of birds

USGS Publications Warehouse

Shufeldt, R. W.

1882-01-01

At the present writing we know of but one species of the so-called Burrowing Owls inhabiting America, and this is represented by three existing races, the typical and largest of those being the Athene cunicularia, a species confined to South America, while its two varieties occur with the limits of the United States.

Impact of changes in GRACE derived terrestrial water storage on vegetation growth in Eurasia

NASA Astrophysics Data System (ADS)

A, G.; Velicogna, I.; Kimball, J. S.; Kim, Y.

2015-12-01

We use GRACE-derived terrestrial water storage (TWS) and ERA-interim air temperature, as proxy for available water and temperature constraints on vegetation productivity, inferred from MODIS satellite normalized difference vegetation index (NDVI), in Northern Eurasia during 2002-2011. We investigate how changes in TWS affect the correlation between NDVI and temperature during the non-frozen season. We find that vegetation growth exhibits significant spatial and temporal variability associated with varying trend in TWS and temperature. The largest NDVI gains occur over boreal forests associated with warming and wetting. The largest NDVI losses occur over grasslands in the Southwestern Ob associated with regional drying and cooling, with dominant constraint from TWS. Over grasslands and temperate forests in the Southeast Ob and South Yenisei, wetting and cooling lead to a dominant temperature constraint due to the relaxation of TWS constraints. Overall, we find significant monthly correlation of NDVI with TWS and temperature over 35% and 50% of the domain, respectively. These results indicate that water availability (TWS) plays a major role in modulating Eurasia vegetation response to temperature changes.

FUEL EFFECTS ON COMBUSTION WITH EGR DILUTION IN SPARK IGNITED ENGINES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Szybist, James P

The use of EGR as a diluent allows operation with an overall stoichiometric charge composition, and the addition of cooled EGR results in well-understood thermodynamic benefits for improved fuel consumption. This study investigates the effect of fuel on the combustion and emission response of EGR dilution in spark ignited engines. A 2.0 L GM Ecotec LNF engine equipped with the production side-mounted direct injection (DI) fueling system is used in this study. Ethanol, isooctane and certified gasoline are investigated with EGR from 0% to the EGR dilution tolerance. Constant BMEP at 2000 rpm was operated with varying CA50 from 8more » CAD to 16 CAD aTDCf. The results show that ethanol gives the largest EGR tolerance at a given combustion phasing, engine load and speed. The improved EGR dilution tolerance with ethanol is attributed to a faster flame speed, which manifests itself as shorter combustion duration. Data shows that the combustion stability limit occurs at a critical combustion duration that is fuel independent. Due to different flame speeds, this critical combustion duration occurs at different EGR levels for the different fuels.« less

On the evolution of specialization with a mechanistic underpinning in structured metapopulations.

PubMed

Nurmi, Tuomas; Parvinen, Kalle

2008-03-01

We analyze the evolution of specialization in resource utilization in a discrete-time metapopulation model using the adaptive dynamics approach. The local dynamics in the metapopulation are based on the Beverton-Holt model with mechanistic underpinnings. The consumer faces a trade-off in the abilities to consume two resources that are spatially heterogeneously distributed to patches that are prone to local catastrophes. We explore the factors favoring the spread of generalist or specialist strategies. Increasing fecundity or decreasing catastrophe probability favors the spread of the generalist strategy and increasing environmental heterogeneity enlarges the parameter domain where the evolutionary branching is possible. When there are no catastrophes, increasing emigration diminishes the parameter domain where the evolutionary branching may occur. Otherwise, the effect of emigration on evolutionary dynamics is non-monotonous: both small and large values of emigration probability favor the spread of the specialist strategies whereas the parameter domain where evolutionary branching may occur is largest when the emigration probability has intermediate values. We compare how different forms of spatial heterogeneity and different models of local growth affect the evolutionary dynamics. We show that even small changes in the resource dynamics may have outstanding evolutionary effects to the consumers.

Two episodes of meltwater influx from glacial Lake Agassiz into the Lake Michigan basin and their climatic contrasts

USGS Publications Warehouse

Colman, Steven M.; Keigwin, L.D.; Forester, R.M.

1994-01-01

Two episodes of meltwater influx from glacial Lake Agassiz are recorded as prominent sedimentologic, isotopic, magnetic, and faunal signatures in southern Lake Michigan profundal sediments. As a tributary to the main path of eastward Lake Agassiz flow, southern Lake Michigan recorded only the largest, catastrophic discharges. The distinctive Wilmette Bed, a massive gray mud that interrrupts laminated red glaciolacustrine clays, marks the first episode, which occurred near the beginning of the Younger Dryas cooling events. The associated discharge may have played a role in the inception or severity of the Younger Dryas event. An oxygen isotope excursion in biogenic carbonate and changes in ostracode assemblages mark the second episode, which appears to have had at least two pulses, dated by accelerator mass spectrometer 14C ages on biogenic carbonate at about 8.9 and 8.6 ka. The second episode occurred during the early Holocene peak in global meltwater discharge and apparently had little widespread climatic or oceanographic effect. The contrast between the effects associated with these two episodes of meltwater discharge emphasizes the complexity of the ice sheet-ocean-climate system. -Authors

Induced earthquake magnitudes are as large as (statistically) expected

USGS Publications Warehouse

Van Der Elst, Nicholas; Page, Morgan T.; Weiser, Deborah A.; Goebel, Thomas; Hosseini, S. Mehran

2016-01-01

A major question for the hazard posed by injection-induced seismicity is how large induced earthquakes can be. Are their maximum magnitudes determined by injection parameters or by tectonics? Deterministic limits on induced earthquake magnitudes have been proposed based on the size of the reservoir or the volume of fluid injected. However, if induced earthquakes occur on tectonic faults oriented favorably with respect to the tectonic stress field, then they may be limited only by the regional tectonics and connectivity of the fault network. In this study, we show that the largest magnitudes observed at fluid injection sites are consistent with the sampling statistics of the Gutenberg-Richter distribution for tectonic earthquakes, assuming no upper magnitude bound. The data pass three specific tests: (1) the largest observed earthquake at each site scales with the log of the total number of induced earthquakes, (2) the order of occurrence of the largest event is random within the induced sequence, and (3) the injected volume controls the total number of earthquakes rather than the total seismic moment. All three tests point to an injection control on earthquake nucleation but a tectonic control on earthquake magnitude. Given that the largest observed earthquakes are exactly as large as expected from the sampling statistics, we should not conclude that these are the largest earthquakes possible. Instead, the results imply that induced earthquake magnitudes should be treated with the same maximum magnitude bound that is currently used to treat seismic hazard from tectonic earthquakes.

On the Sizes of the North Atlantic Basin Tropical Cyclones Based on 34- and 64-kt Wind Radii Data, 2004-2013

NASA Technical Reports Server (NTRS)

Wilson, Robert M.

2014-01-01

At end of the 2012 hurricane season the National Hurricane Center retired the original HURDAT dataset and replaced it with the newer version HURDAT2, which reformatted the original data and included additional information, in particular, estimates of the 34-, 50, and 64-kt wind radii for the interval 2004-2013. During the brief 10-year interval, some 164 tropical cyclones are noted to have formed in the North Atlantic basin, with 77 becoming hurricanes. Hurricane Sandy (2012) stands out as being the largest individual storm that occurred in the North Atlantic basin during the 2004 -2013 timeframe, both in terms of its 34- and 64-kt wind radii and wind areas, having maximum 34- and 64-kt wind radii, maximum wind areas, and average wind areas each more than 2 standard deviations larger than the corresponding means. In terms of the largest yearly total 34-kt wind area (i.e., the sum of all individual storm 34-kt wind areas during the year), the year 2010 stands out as being the largest (about 423 × 10(exp 6) nmi(exp 2)), compared to the mean of about 174 × 10(exp 6) nmi(exp 2)), surpassing the year 2005 (353 x 10(exp 6) nmi(exp 2)) that had the largest number of individual storms (28). However, in terms of the largest yearly total 64-kt wind area, the year 2005 was the largest (about 9 × 10(exp 6) nmi(exp 2)), compared to the mean of about 3 × 106 nmi(exp 2)). Interesting is that the ratio of total 64-kt wind area to total 34-kt wind area has decreased over time, from 0.034 in 2004 to 0.008 in 2013.

A study of the geomagnetic indices asymmetry based on the interplanetary magnetic field polarities

NASA Astrophysics Data System (ADS)

El-Borie, M. A.; El-Taher, A. M.; Aly, N. E.; Bishara, A. A.

2018-05-01

Data of geomagnetic indices ( aa, Kp, Ap, and Dst) recorded near 1 AU over the period 1967-2016, have been studied based on the asymmetry between the interplanetary magnetic field (IMF) directions above and below of the heliospheric current sheet (HCS). Our results led to the following conclusions: (i) Throughout the considered period, 31 random years (62%) showed apparent asymmetries between Toward (T) and Away (A) polarity days and 19 years (38%) exhibited nearly a symmetrical behavior. The days of A polarity predominated over the T polarity days by 4.3% during the positive magnetic polarity epoch (1991-1999). While the days of T polarity exceeded the days of A polarity by 5.8% during the negative magnetic polarity epoch (2001-2012). (ii) Considerable yearly North-South (N-S) asymmetries of geomagnetic indices observed throughout the considered period. (iii) The largest toward dominant peaks for aa and Ap indices occurred in 1995 near to minimum of solar activity. Moreover, the most substantial away dominant peaks for aa and Ap indices occurred in 2003 (during the descending phase of the solar cycle 23) and in 1991 (near the maximum of solar activity cycle) respectively. (iv) The N-S asymmetry of Kp index indicated a most significant away dominant peak occurred in 2003. (v) Four of the away dominant peaks of Dst index occurred at the maxima of solar activity in the years 1980, 1990, 2000, and 2013. The largest toward dominant peak occurred in 1991 (at the reversal of IMF polarity). (vi) The geomagnetic indices ( aa, Ap, and Kp) all have northern dominance during positive magnetic polarity epoch (1971-1979), while the asymmetries shifts to the southern solar hemisphere during negative magnetic polarity epoch (2001-2012).

Wrinkle ridges in the floor material of Kasei Valles, Mars: Nature and origin

NASA Technical Reports Server (NTRS)

Watters, Thomas R.; Craddock, Robert A.

1991-01-01

Wrinkle ridges on Mars occur almost exclusively in smooth plains material referred to as ridged plains. One of the largest contiguous units of ridged plains occurs on Lunae Planum on the eastern flank of the Tharsis rise. The eastern, western, and northern margins of the ridged plains of Lunae Planum suffered extensive erosion in early Amazonian channel-forming events. The most dramatic example of erosion in early Amazonian plains is in Kasei Valles. The nature an origin of the wrinkle ridges in the floor material of Kasei Valles are discussed.

Pressure demagnetization of synthetic Al substituted hematite and its implications for planetary studies

NASA Astrophysics Data System (ADS)

Jiang, Zhaoxia; Rochette, Pierre; Liu, Qingsong; Gattacceca, Jérôme; Yu, Yongjae; Barrón, Vidal; Torrent, José

2013-11-01

Magnetic minerals can undergo high pressures during their formation and subsequent evolution, which can modify both their intrinsic magnetic properties and remanent magnetization. Aluminum-substituted hematite (Al-hematite) occurs in significant proportion in many soils and sediments, especially in temperate and warm areas. In this work we investigated the effect of high hydrostatic pressures on the magnetic remanence of two series of synthetic Al-hematites. A pressure of 1.44 GPa resulted in 50% reduction of the isothermal remanent magnetization (IRM), which was more effective than alternating field (AF) demagnetization with the largest peak field of 120 mT. In addition, repeated application of the same pressure leads to further demagnetization. Aluminum substitution may increase the resistance to the pressure effect by decreasing particle size and generating defects in magnetic lattices, which results in an increase in coercivity. Our study contributes to understanding the effects of pressure on rocks from the interior of Earth and other planets as well as shocked planetary surfaces, which is significant for future planetary studies.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lin Shoufu, E-mail: linshf2003@126.co; Zhao Dingtao, E-mail: box@ustc.edu.c; Marinova, Dora, E-mail: D.Marinova@curtin.edu.a

Assuming that energy consumption is the main source of GHG emissions in China, this paper analyses the effect of population, urbanisation level, GDP per capita, industrialisation level and energy intensity on the country's environmental impact using the STIRPAT model with data for 1978-2006. The analysis shows that population has the largest potential effect on environmental impact, followed by urbanisation level, industrialisation level, GDP per capita and energy intensity. Hence, China's One Child Policy, which restrains rapid population growth, has been an effective way of reducing the country's environmental impact. However, due to the difference in growth rates, GDP per capitamore » had a higher effect on the environmental impact, contributing to 38% of its increase (while population's contribution was at 32%). The rapid decrease in energy intensity was the main factor restraining the increase in China's environmental impact but recently it has also been rising. Against this background, the future of the country looks bleak unless a change in human behaviour towards more ecologically sensitive economic choices occurs.« less

Assessing the effect of elevated carbon dioxide on soil carbon: a comparison of four meta-analyses.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hungate, B. A.; van Groenigen, K.; Six, J.

2009-08-01

Soil is the largest reservoir of organic carbon (C) in the terrestrial biosphere and soil C has a relatively long mean residence time. Rising atmospheric carbon dioxide (CO{sub 2}) concentrations generally increase plant growth and C input to soil, suggesting that soil might help mitigate atmospheric CO{sub 2} rise and global warming. But to what extent mitigation will occur is unclear. The large size of the soil C pool not only makes it a potential buffer against rising atmospheric CO{sub 2}, but also makes it difficult to measure changes amid the existing background. Meta-analysis is one tool that can overcomemore » the limited power of single studies. Four recent meta-analyses addressed this issue but reached somewhat different conclusions about the effect of elevated CO{sub 2} on soil C accumulation, especially regarding the role of nitrogen (N) inputs. Here, we assess the extent of differences between these conclusions and propose a new analysis of the data. The four meta-analyses included different studies, derived different effect size estimates from common studies, used different weighting functions and metrics of effect size, and used different approaches to address nonindependence of effect sizes. Although all factors influenced the mean effect size estimates and subsequent inferences, the approach to independence had the largest influence. We recommend that meta-analysts critically assess and report choices about effect size metrics and weighting functions, and criteria for study selection and independence. Such decisions need to be justified carefully because they affect the basis for inference. Our new analysis, with a combined data set, confirms that the effect of elevated CO{sub 2} on net soil C accumulation increases with the addition of N fertilizers. Although the effect at low N inputs was not significant, statistical power to detect biogeochemically important effect sizes at low N is limited, even with meta-analysis, suggesting the continued need for long-term experiments.« less

Data Assimilation by Ensemble Kalman Filter during One-Dimensional Nonlinear Consolidation in Randomly Heterogeneous Highly Compressible Aquitards

NASA Astrophysics Data System (ADS)

Zapata Norberto, B.; Morales-Casique, E.; Herrera, G. S.

2017-12-01

Severe land subsidence due to groundwater extraction may occur in multiaquifer systems where highly compressible aquitards are present. The highly compressible nature of the aquitards leads to nonlinear consolidation where the groundwater flow parameters are stress-dependent. The case is further complicated by the heterogeneity of the hydrogeologic and geotechnical properties of the aquitards. We explore the effect of realistic vertical heterogeneity of hydrogeologic and geotechnical parameters on the consolidation of highly compressible aquitards by means of 1-D Monte Carlo numerical simulations. 2000 realizations are generated for each of the following parameters: hydraulic conductivity (K), compression index (Cc) and void ratio (e). The correlation structure, the mean and the variance for each parameter were obtained from a literature review about field studies in the lacustrine sediments of Mexico City. The results indicate that among the parameters considered, random K has the largest effect on the ensemble average behavior of the system. Random K leads to the largest variance (and therefore largest uncertainty) of total settlement, groundwater flux and time to reach steady state conditions. We further propose a data assimilation scheme by means of ensemble Kalman filter to estimate the ensemble mean distribution of K, pore-pressure and total settlement. We consider the case where pore-pressure measurements are available at given time intervals. We test our approach by generating a 1-D realization of K with exponential spatial correlation, and solving the nonlinear flow and consolidation problem. These results are taken as our "true" solution. We take pore-pressure "measurements" at different times from this "true" solution. The ensemble Kalman filter method is then employed to estimate ensemble mean distribution of K, pore-pressure and total settlement based on the sequential assimilation of these pore-pressure measurements. The ensemble-mean estimates from this procedure closely approximate those from the "true" solution. This procedure can be easily extended to other random variables such as compression index and void ratio.

A Novel and Functional Single-Layer Sheet of ZnSe

DOE PAGES

Zhou, Jia; Sumpter, Bobby G.; Kent, Paul R. C.; ...

2014-12-23

In this Communication, we report a novel singlelayer sheet of ZnSe, with a three-atomic thickness, which demonstrates a strong quantum confinement effect by exhibiting a large blue shift of 2.0 eV in its absorption edge relative to the zinc blende (ZB) bulk phase. Theoretical optical absorbance shows that the largest absorption of this ultrathin single-layer sheet of ZnSe occurs at a wavelength similar to its four-atom-thick doublelayer counterpart but with higher photoabsorption efficiency, suggesting a superior behavior on incident photon-to-current conversion efficiency for solar water splitting, among other potential applications. The results presented herein for ZnSe may be generalized tomore » other group II-VI analogues.« less

The Evidence Regarding Maintenance Tocolysis

PubMed Central

Elliott, John P.; Morrison, John C.

2013-01-01

Preterm delivery is a public health issue of major proportion. More than 12% of deliveries in the United States that occur at less than 37 weeks gestation preterm labor (PTL) represents the largest single reason for preterm birth (PTB). Attempts to prevent PTB have been unsuccessful. This paper of maintenance tocolytic therapy will examine the efficacy and safety of the drugs, both oral and subcutaneous, which have been utilized for prolongation of pregnancy following successful arrest of a documented episode of acute preterm labor. The evidence for oral tocolytics as maintenance therapy as well as parenteral medications for such patients is offered. Finally, the effects in the United States of the Food and Drug Administration (FDA) action on such medications are reported. PMID:23577034

Investigating the Effect of Impurities on Macromolecule Crystal Growth in Microgravity

NASA Technical Reports Server (NTRS)

Snell, Edward H.; Judge, Russell A.; Crawford, Lisa; Forsythe, Elizabeth L.; Pusey, Marc L.; Sportiello, Michael; Todd, Paul; Bellamy, Henry; Lovelace, Jeff; Cassanto, John M.;

The influence of head diameter and wall thickness on deformations of metallic acetabular press-fit cups and UHMWPE liners: a finite element analysis.

PubMed

Goebel, Paul; Kluess, Daniel; Wieding, Jan; Souffrant, Robert; Heyer, Horst; Sander, Manuela; Bader, Rainer

2013-03-01

To increase the range of motion of total hip endoprostheses, prosthetic heads need to be enlarged, which implies that the cup and/or liner thickness must decrease. This may have negative effects on the wear rate, because the acetabular cups and liners could deform during press-fit implantation and hip joint loading. We compared the metal cup and polyethylene liner deformations that occurred when different wall thicknesses were used in order to evaluate the resulting changes in the clearance of the articulating region. A parametric finite element model utilized three cup and liner wall thicknesses to analyze cup and liner deformations after press-fit implantation into the pelvic bone. The resultant hip joint force during heel strike was applied while the femur was fixed, accounting for physiological muscle forces. The deformation behavior of the liner under joint loading was therefore assessed as a function of the head diameter and the resulting clearance. Press-fit implantation showed diametral cup deformations of 0.096, 0.034, and 0.014 mm for cup wall thicknesses of 3, 5, and 7 mm, respectively. The largest deformations (average 0.084 ± 0.003 mm) of liners with thicknesses of 4, 6, and 8 mm occurred with the smallest cup wall thickness (3 mm). The smallest liner deformation (0.011 mm) was obtained with largest cup and liner wall thicknesses. Under joint loading, liner deformations in thin-walled acetabular cups (3 mm) reduced the initial clearance by about 50 %. Acetabular press-fit cups with wall thicknesses of ≤5 mm should only be used in combination with polyethylene liners >6 mm thick in order to minimize the reduction in clearance.

Mechanical coupling between earthquakes and volcanoes inferred from stress transfer models: evidence from Vesuvio, Etna and Alban Hills (Italy)

NASA Astrophysics Data System (ADS)

Cocco, M.; Feuillet, N.; Nostro, C.; Musumeci, C.

2003-04-01

We investigate the mechanical interactions between tectonic faults and volcanic sources through elastic stress transfer and discuss the results of several applications to Italian active volcanoes. We first present the stress modeling results that point out a two-way coupling between Vesuvius eruptions and historical earthquakes in Southern Apennines, which allow us to provide a physical interpretation of their statistical correlation. Therefore, we explore the elastic stress interaction between historical eruptions at the Etna volcano and the largest earthquakes in Eastern Sicily and Calabria. We show that the large 1693 seismic event caused an increase of compressive stress along the rift zone, which can be associated to the lack of flank eruptions of the Etna volcano for about 70 years after the earthquake. Moreover, the largest Etna eruptions preceded by few decades the large 1693 seismic event. Our modeling results clearly suggest that all these catastrophic events are tectonically coupled. We also investigate the effect of elastic stress perturbations on the instrumental seismicity caused by magma inflation at depth both at the Etna and at the Alban Hills volcanoes. In particular, we model the seismicity pattern at the Alban Hills volcano (central Italy) during a seismic swarm occurred in 1989-90 and we interpret it in terms of Coulomb stress changes caused by magmatic processes in an extensional tectonic stress field. We verify that the earthquakes occur in areas of Coulomb stress increase and that their faulting mechanisms are consistent with the stress perturbation induced by the volcanic source. Our results suggest a link between faults and volcanic sources, which we interpret as a tectonic coupling explaining the seismicity in a large area surrounding the volcanoes.

Interior Least Tern (Sternula antillarum) breeding distribution and ecology: implications for population-level studies and the evaluation of alternative management strategies on large, regulated rivers

PubMed Central

Lott, Casey A; Wiley, Robert L; Fischer, Richard A; Hartfield, Paul D; Scott, J Michael

2013-01-01

Interior Least Terns (Sternula antillarum) (ILT) are colonial, fish-eating birds that breed within active channels of large sand bed rivers of the Great Plains and in the Lower Mississippi Valley. Multipurpose dams, irrigation structures, and engineered navigation systems have been present on these rivers for many decades. Despite severe alteration of channels and flow regimes, regulation era floods have remained effective at maintaining bare sandbar nesting habitat on many river segments and ILT populations have been stable or expanding since they were listed as endangered in 1985. We used ILT breeding colony locations from 2002 to 2012 and dispersal information to identify 16 populations and 48 subpopulations. More than 90% of ILT and >83% of river km with suitable nesting habitat occur within the two largest populations. However, replicate populations remain throughout the entire historical, geophysical, and ecological range of ILT. Rapid colonization of anthropogenic habitats in areas that were not historically occupied suggests metapopulation dynamics. The highest likelihood of demographic connectivity among ILT populations occurs across the Southern Plains and the Lower Mississippi River, which may be demographically connected with Least Tern populations on the Gulf Coast. Paired ecological and bird population models are needed to test whether previously articulated threats limit ILT population growth and to determine if management intervention is necessary and where. Given current knowledge, the largest sources of model uncertainty will be: (1) uncertainty in relationships between high flow events and subsequent sandbar characteristics and (2) uncertainty regarding the frequency of dispersal among population subunits. We recommend research strategies to reduce these uncertainties. PMID:24223295

Stereo Particle Image Velocimetry Measurements of Transition Downstream of a Forward-Facing Step in a Swept-Wing Boundary Layer

NASA Technical Reports Server (NTRS)

Eppink, Jenna L.

2017-01-01

Stereo particle image velocimetry measurements were performed downstream of a forward-facing step in a stationary-crossflow dominated flow. Three different step heights were studied with the same leading-edge roughness configuration to determine the effect of the step on the evolution of the stationary-crossflow. Above the critical step height, which is approximately 68% of the boundary-layer thickness at the step, the step caused a significant increase in the growth of the stationary crossflow. For the largest step height studied (68%), premature transition occurred shortly downstream of the step. The stationary crossflow amplitude only reached approximately 7% of U(sub e) in this case, which suggests that transition does not occur via the high-frequency secondary instabilities typically associated with stationary crossflow transition. The next largest step of 60% delta still caused a significant impact on the growth of the stationary crossflow downstream of the step, but the amplitude eventually returned to that of the baseline case, and the transition front remained the same. The smallest step height (56%) only caused a small increase in the stationary crossflow amplitude and no change in the transition front. A final case was studied in which the roughness on the leading edge of the model was enhanced for the lowest step height case to determine the impact of the stationary crossflow amplitude on transition. The stationary crossflow amplitude was increased by approximately four times, which resulted in premature transition for this step height. However, some notable differences were observed in the behavior of the stationary crossflow mode, which indicate that the interaction mechanism which results in the increased growth of the stationary crossflow downstream of the step may be different in this case compared to the larger step heights.

Fast and Slow Spindles during the Sleep Slow Oscillation: Disparate Coalescence and Engagement in Memory Processing

PubMed Central

Mölle, Matthias; Bergmann, Til O.; Marshall, Lisa; Born, Jan

2011-01-01

Study Objectives: Thalamo-cortical spindles driven by the up-state of neocortical slow (< 1 Hz) oscillations (SOs) represent a candidate mechanism of memory consolidation during sleep. We examined interactions between SOs and spindles in human slow wave sleep, focusing on the presumed existence of 2 kinds of spindles, i.e., slow frontocortical and fast centro-parietal spindles. Design: Two experiments were performed in healthy humans (24.5 ± 0.9 y) investigating undisturbed sleep (Experiment I) and the effects of prior learning (word paired associates) vs. non-learning (Experiment II) on multichannel EEG recordings during sleep. Measurements and Results: Only fast spindles (12-15 Hz) were synchronized to the depolarizing SO up-state. Slow spindles (9-12 Hz) occurred preferentially at the transition into the SO down-state, i.e., during waning depolarization. Slow spindles also revealed a higher probability to follow rather than precede fast spindles. For sequences of individual SOs, fast spindle activity was largest for “initial” SOs, whereas SO amplitude and slow spindle activity were largest for succeeding SOs. Prior learning enhanced this pattern. Conclusions: The finding that fast and slow spindles occur at different times of the SO cycle points to disparate generating mechanisms for the 2 kinds of spindles. The reported temporal relationships during SO sequences suggest that fast spindles, driven by the SO up-state feed back to enhance the likelihood of succeeding SOs together with slow spindles. By enforcing such SO-spindle cycles, particularly after prior learning, fast spindles possibly play a key role in sleep-dependent memory processing. Citation: Mölle M; Bergmann TO; Marshall L; Born J. Fast and slow spindles during the sleep slow oscillation: disparate coalescence and engagement in memory processing. SLEEP 2011;34(10):1411–1421. PMID:21966073

Evidence for protection of targeted reef fish on the largest marine reserve in the Caribbean

PubMed Central

Pina-Amargós, Fabián; González-Sansón, Gaspar; Martín-Blanco, Félix

2014-01-01

Marine reserves can restore fish abundance and diversity in areas impacted by overfishing, but the effectiveness of reserves in developing countries where resources for enforcement are limited, have seldom been evaluated. Here we assess whether the establishment in 1996 of the largest marine reserve in the Caribbean, Gardens of the Queen in Cuba, has had a positive effect on the abundance of commercially valuable reef fish species in relation to neighboring unprotected areas. We surveyed 25 sites, including two reef habitats (reef crest and reef slope), inside and outside the marine reserve, on five different months, and over a one-and-a-half year period. Densities of the ten most frequent, highly targeted, and relatively large fish species showed a significant variability across the archipelago for both reef habitats that depended on the month of survey. These ten species showed a tendency towards higher abundance inside the reserve in both reef habitats for most months during the study. Average fish densities pooled by protection level, however, showed that five out of these ten species were at least two-fold significantly higher inside than outside the reserve at one or both reef habitats. Supporting evidence from previously published studies in the area indicates that habitat complexity and major benthic communities were similar inside and outside the reserve, while fishing pressure appeared to be homogeneous across the archipelago before reserve establishment. Although poaching may occur within the reserve, especially at the boundaries, effective protection from fishing was the most plausible explanation for the patterns observed. PMID:24688853

Evidence for protection of targeted reef fish on the largest marine reserve in the Caribbean.

PubMed

Pina-Amargós, Fabián; González-Sansón, Gaspar; Martín-Blanco, Félix; Valdivia, Abel

2014-01-01

Marine reserves can restore fish abundance and diversity in areas impacted by overfishing, but the effectiveness of reserves in developing countries where resources for enforcement are limited, have seldom been evaluated. Here we assess whether the establishment in 1996 of the largest marine reserve in the Caribbean, Gardens of the Queen in Cuba, has had a positive effect on the abundance of commercially valuable reef fish species in relation to neighboring unprotected areas. We surveyed 25 sites, including two reef habitats (reef crest and reef slope), inside and outside the marine reserve, on five different months, and over a one-and-a-half year period. Densities of the ten most frequent, highly targeted, and relatively large fish species showed a significant variability across the archipelago for both reef habitats that depended on the month of survey. These ten species showed a tendency towards higher abundance inside the reserve in both reef habitats for most months during the study. Average fish densities pooled by protection level, however, showed that five out of these ten species were at least two-fold significantly higher inside than outside the reserve at one or both reef habitats. Supporting evidence from previously published studies in the area indicates that habitat complexity and major benthic communities were similar inside and outside the reserve, while fishing pressure appeared to be homogeneous across the archipelago before reserve establishment. Although poaching may occur within the reserve, especially at the boundaries, effective protection from fishing was the most plausible explanation for the patterns observed.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hamoda, Haitham, E-mail: haithamhamoda@hotmail.co; Tait, P.; Edmonds, D. K.

We report a 44-year-old woman who developed a fatal pulmonary embolus after uterine artery fibroid embolisation (UAE). Bilateral UAE was carried out through a single right-femoral artery puncture. The largest fibroid in the anterior fundal wall measured 4.5 cm, and the largest fibroid in the posterior fundal wall measured 6 cm. The appearances after UAE were satisfactory, and the procedure was apparently uneventful. No immediate complications were noted. The patient developed sudden-onset shortness of breath and went into cardiac arrest 19 h after the procedure. Postmortem autopsy confirmed that the cause of a death was a pulmonary embolism. To ourmore » knowledge this is the first reported case in the United Kingdom in which death occurred from a pulmonary embolus after UAE.« less

Glaciers of South America

USGS Publications Warehouse

Williams, Richard S.; Ferrigno, Jane G.

1998-01-01

Landsat images, together with maps and aerial photographs, have been used to produce glacier inventories, define glacier locations, and study glacier dynamics in the countries of South America, along with the Andes Mountains. In Venezuela, Colombia, Ecuador, and Bolivia, the small glaciers have been undergoing extensive glacier recession since the late 1800's. Glacier-related hazards (outburst floods, mud flows, and debris avalanches) occur in Colombia, in Ecuador, and associated with the more extensive (2,600 km2) glaciers of Peru. The largest area of glacier ice is found in Argentina and Chile, including the northern Patagonian ice field (about 4,200 km2) and the southern Patagonian ice field (about 13,000 km2), the largest glacier in the Southern Hemisphere outside Antarctica.

Qal'eh Hasan Ali maars, central Iran.

USGS Publications Warehouse

Milton, D.J.

1976-01-01

This group of some 15 Late Quaternary explosion craters are typical maars, with rims of bedded pyroclastics. In all but the largest crater, the deposits consist entirely of clasts of country rock (granodiorite and Eocene volcanics). The maars were formed by phreatomagmatic explosions, possibly caused by groundwater originating from a major river. The deposits of the largest maar contain up to 20% juvenile fragments of two types. Tephrite clasts have phenocrysts of phlogopite, clinopyroxene, olivine and anorthoclase; the presence of hauyne as a groundmass phase is notable. Cumulate blocks of phlogopite-clinopyroxene rock also occur. The maar field is part of a distinct province of Quaternary alkaline volcanism, related to a major crustal fracture - the N-S-trending Nayband fault.-R.J.S.

Profiles of behavioral problems in children who witness domestic violence.

PubMed

Spilsbury, James C; Kahana, Shoshana; Drotar, Dennis; Creeden, Rosemary; Flannery, Daniel J; Friedman, Steve

2008-01-01

Unlike previous investigations of shelter-based samples, our study examined whether profiles of adjustment problems occurred in a community-program-based sample of 175 school-aged children exposed to domestic violence. Cluster analysis revealed three stable profiles/clusters. The largest cluster (69%) consisted of children below clinical thresholds for any internalizing or externalizing problem. Children in the next largest cluster (18%) were characterized as having externalizing problems with or without internalizing problems. The smallest cluster (13%) consisted of children with internalizing problems only. Comparison across demographic and violence characteristics revealed that the profiles differed by child gender, mother's education, child's lifetime exposure to violence, and aspects of the event precipitating contact with the community program. Clinical and future research implications of study findings are discussed.

Simulated and measured water levels and estimated water-level changes in the Albuquerque area, central New Mexico, 1950-2012

USGS Publications Warehouse

Rice, Steven E.; Oelsner, Gretchen P.; Heywood, Charles E.

2014-01-01

and again for 2008. Both the water-table elevations and production-zone hydraulic heads declined over time with the largest change occurring between 1970 and 1980, which was a period of rapid population growth and groundwater use. Declines in the water-table elevations and production-zone hydraulic heads are focused around major pumping centers and are largest in the production zone. Hydrographs from nine production-zone piezometers in the modeled area indicated varying responses to the increased use of surface-water diversions during 2009–12, with responses related to the locations of the wells within the study area and their proximity to pumping centers and the Rio Grande.

Climatology of extreme daily precipitation in Colorado and its diverse spatial and seasonal variability

USGS Publications Warehouse

Mahoney, Kelly M.; Ralph, F. Martin; Walter, Klaus; Doesken, Nolan; Dettinger, Michael; Gottas, Daniel; Coleman, Timothy; White, Allen

2015-01-01

The climatology of Colorado’s historical extreme precipitation events shows a remarkable degree of seasonal and regional variability. Analysis of the largest historical daily precipitation totals at COOP stations across Colorado by season indicates that the largest recorded daily precipitation totals have ranged from less than 60 mm day−1 in some areas to more than 250 mm day−1 in others. East of the Continental Divide, winter events are rarely among the top 10 events at a given site, but spring events dominate in and near the foothills; summer events are most common across the lower-elevation eastern plains, while fall events are most typical for the lower elevations west of the Divide. The seasonal signal in Colorado’s central mountains is complex; high-elevation intense precipitation events have occurred in all months of the year, including summer, when precipitation is more likely to be liquid (as opposed to snow), which poses more of an instantaneous flood risk. Notably, the historic Colorado Front Range daily rainfall totals that contributed to the damaging floods in September 2013 occurred outside of that region’s typical season for most extreme precipitation (spring–summer). That event and many others highlight the fact that extreme precipitation in Colorado has occurred historically during all seasons and at all elevations, emphasizing a year-round statewide risk.

Isolated intermediate-depth seismicity north of the Izu peninsula, Japan: implications for subduction of the Philippine Sea Plate

NASA Astrophysics Data System (ADS)

Nakajima, Junichi

2018-01-01

The subduction of the Philippine Sea (PHS) Plate toward the north of Izu peninsula, Japan, is of great interest because intraslab seismicity is absent where the buoyant Izu volcanic arc has been subducting over the past 15 Myr. This study analyzes 42 earthquakes in an isolated seismic cluster that occurred 100 km north of Izu peninsula at depths of 40-90 km and discusses seismogenesis in the context of plate subduction. We picked P- and S-wave arrival times of earthquakes to produce a complete hypocenter catalogue, carried out double-difference event relocations, and then determined focal mechanism solutions of 7 earthquakes from P-wave polarity data. Based on the focal mechanism solution, the largest earthquake (M3.1) is interpreted as a thrust earthquake along the upper surface of the PHS Plate. Locations of other earthquakes relative to the largest event suggest that most earthquakes occur within the subducting PHS Plate. Our results suggest that the PHS Plate north of Izu peninsula has temperatures low enough to facilitate thrust and intraslab earthquakes at depths of 60-90 km. Earthquakes are likely to occur where pore pressures are locally high, which weakens pre-existing faults. The presence of the intermediate-depth seismic cluster indicates the continuous subduction of the PHS Plate toward the north of Izu peninsula without any disruption.[Figure not available: see fulltext.

Review of research on impacts to biota of discharges of naturally occurring radionuclides in produced water to the marine environment.

PubMed

Hosseini, Ali; Brown, Justin E; Gwynn, Justin P; Dowdall, Mark

2012-11-01

Produced water has been described as the largest volume waste stream in the exploration and production process of oil and gas. It is accompanied by discharges of naturally occurring radionuclides raising concerns over the potential radiological impacts of produced water on marine biota. In the Northern European marine environment, radioactivity in produced water has received substantial attention owing to the OSPAR Radioactive Substances Strategy which aims at achieving 'concentrations in the environment near background values for naturally occurring radioactive substances'. This review provides an overview of published research on the impacts to biota from naturally occurring radionuclides discharged in produced water by the offshore oil and gas industry. In addition to summarising studies and data that deal directly with the issue of dose and effect, the review also considers studies related to the impact of added chemicals on the fate of discharged radionuclides. The review clearly illustrates that only a limited number of studies have investigated possible impacts on biota from naturally occurring radionuclides present in produced water. Hence, although these studies indicate that the risk to the environment from naturally occurring radionuclides discharged in produced water is negligible, the substantial uncertainties involved in the assessments of impact make it difficult to be conclusive. With regard to the complexity involved in the problem under consideration there is a pressing need to supplement existing data and acquire new knowledge. Finally, the present work identifies some knowledge gaps to indicate future research requirements. Copyright © 2012 Elsevier B.V. All rights reserved.

Simulator study of the effect of visual-motion time delays on pilot tracking performance with an audio side task

NASA Technical Reports Server (NTRS)

Riley, D. R.; Miller, G. K., Jr.

1978-01-01

The effect of time delay was determined in the visual and motion cues in a flight simulator on pilot performance in tracking a target aircraft that was oscillating sinusoidally in altitude only. An audio side task was used to assure the subject was fully occupied at all times. The results indicate that, within the test grid employed, about the same acceptable time delay (250 msec) was obtained for a single aircraft (fighter type) by each of two subjects for both fixed-base and motion-base conditions. Acceptable time delay is defined as the largest amount of delay that can be inserted simultaneously into the visual and motion cues before performance degradation occurs. A statistical analysis of the data was made to establish this value of time delay. Audio side task provided quantitative data that documented the subject's work level.

Effects of charge noise on a pulse-gated singlet-triplet S - T_ qubit

DOE Office of Scientific and Technical Information (OSTI.GOV)

Qi, Zhenyi; Wu, X.; Ward, D. R.

Here, we study the dynamics of a pulse-gated semiconductor double-quantum-dot qubit. In our experiments, the qubit coherence times are relatively long, but the visibility of the quantum oscillations is low. We also show that these observations are consistent with a theory that incorporates decoherence arising from charge noise that gives rise to detuning fluctuations of the double dot. Because effects from charge noise are largest near the singlet-triplet avoided level crossing, the visibility of the oscillations is low when the singlet-triplet avoided level crossing occurs in the vicinity of the charge degeneracy point crossed during the manipulation, but there ismore » only modest dephasing at the large detuning value at which the quantum phase accumulates. This theory also agrees with experimental data and predicts that the visibility can be increased greatly by appropriate tuning of the interdot tunneling rate.« less

Behavioral and Emotional Problems Associated With Convergence Insufficiency in Children: An Open Trial.

PubMed

Borsting, Eric; Mitchell, G Lynn; Arnold, L Eugene; Scheiman, Mitchell; Chase, Christopher; Kulp, Marjean; Cotter, Susan

2016-10-01

This study investigated behavioral and emotional characteristics of children with convergence insufficiency (CI), before and after treatment with office-based vergence accommodative therapy (OBVAT). Parents of 44 children ages 9 to 17 years with symptomatic CI completed the Conners 3 ADHD Index and the Child Behavior Checklist (CBCL) before and after OBVAT. Pre-treatment scores were compared with normative data and post-treatment scores were compared with baseline using the Wilcoxon sign rank test. Following OBVAT, CI children showed a significant mean improvement (p < .0001, effect size of 0.58) on the Conners 3 ADHD Index with the largest changes occurring in the 23 children who scored the highest at baseline. On the CBCL, anxious/depressed, somatic, and internalizing problems improved significantly (p < .001, effect sizes of -0.36, -1.15, and -0.67, respectively). In an open trial, attention and internalizing problems improved significantly following treatment for CI. © The Author(s) 2013.

Effects of charge noise on a pulse-gated singlet-triplet S - T_ qubit

DOE PAGES

Qi, Zhenyi; Wu, X.; Ward, D. R.; ...

2017-09-11

Here, we study the dynamics of a pulse-gated semiconductor double-quantum-dot qubit. In our experiments, the qubit coherence times are relatively long, but the visibility of the quantum oscillations is low. We also show that these observations are consistent with a theory that incorporates decoherence arising from charge noise that gives rise to detuning fluctuations of the double dot. Because effects from charge noise are largest near the singlet-triplet avoided level crossing, the visibility of the oscillations is low when the singlet-triplet avoided level crossing occurs in the vicinity of the charge degeneracy point crossed during the manipulation, but there ismore » only modest dephasing at the large detuning value at which the quantum phase accumulates. This theory also agrees with experimental data and predicts that the visibility can be increased greatly by appropriate tuning of the interdot tunneling rate.« less

Manufacturer-provided effective orifice area index charts and the prevention of prosthesis-patient mismatch.

PubMed

House, Chad M; Nelson, William B; Kroshus, Timothy J; Dahiya, Ranjan; Pibarot, Philippe

2012-01-01

Prosthesis-patient mismatch (PPM) occurs when an implanted prosthesis is too small relative to the patient's body surface area (BSA). However, mismatch can often be prevented by indexing the expected effective orifice area (EOA) of a prosthesis to the patient's BSA and then selecting the largest implantable prosthesis to avoid mismatch. Previously, prosthesis manufacturers have attempted to simplify this process by providing charts that include the expected EOA for their prosthesis, already indexed into an array of BSA values. One caveat with these charts is that the expected EOA data must truly be reliable, or the charts will misguide the implanting surgeon. Manufacturer-provided charts could be improved by standardizing the EOA data, with one potential source being the hemodynamic data submitted to the United States Food and Drug Administration. This review discusses PPM, manufacturer-provided EOA charts, and the regulation of EOA data.

Precipitation chemistry at the Marcell Experimental Forest in north central Minnesota

Treesearch

Elon S. Verry

1983-01-01

Concentration (milligrams and microequivalents per liter) values are presented for major ions occurring in rain and snow from July 1978 to July 1980. Ammonium, sodium, and calcium are the largest equivalent weight cations which are largely balanced by sulfate and nitrate anions. Hydrogen is the fourth most abundant cation; but high combined concentrations of other...

Impacts of the Deepwater Horizon oil spill on blue crab, Callinectes sapidus, larval settlement in Mississippi

EPA Science Inventory

The largest accidental release of crude oil in history occurred in the north-central Gulf of Mexico (GOM) between April 20 and July 15, 2010 (Alford et al., this volume). The DWH spill was unprecedented due to both its magnitude (>600,000 metric tons released) and its occurren...

Bark beetle outbreaks in western North America: Causes and consequences

Treesearch

Barbara Bentz; Jesse Logan; Jim MacMahon; Craig D. Allen; Matt Ayres; Ed Berg; Allan Carroll; Matt Hansen; Jeff Hicke; Linda Joyce; Wallace Macfarlane; Steve Munson; Jose Negron; Tim Paine; Jim Powell; Ken Raffa; Jacques Regniere; Mary Reid; Bill Romme; Steven J. Seybold; Diana Six; Diana Tomback; Jim Vandygriff; Tom Veblen; Mike White; Jeff Witcosky; David Wood

2009-01-01

Since 1990, native bark beetles have killed billions of trees across millions of acres of forest from Alaska to northern Mexico. Although bark beetle infestations are a regular force of natural change in forested ecosystems, several of the current outbreaks, which are occurring simultaneously across western North America, are the largest and most severe in recorded...

Using Cross-Curricular Ideas to Infuse Paralympic Sport

ERIC Educational Resources Information Center

Tepfer, Amanda T. S.; Lieberman, Lauren J.

2012-01-01

The Paralympic Games are the second largest sport event in the world. They occur two weeks after the Olympic Games in the same geographic location and sport venues. Despite the Paralympic Games' longevity, many Americans do not even know they exist. One way to meaningfully share information about this event with people of all ages is to infuse a…

Bark beetle outbreaks in western North America: Causes and consequences

USGS Publications Warehouse

Bentz, Barbara; Logan, Jesse; MacMahon, James A.; Allen, Craig D.; Ayres, Matt; Berg, Edward E; Carroll, Allan; Hansen, Matt; Hicke, Jeff H.; Joyce, Linda A.; Macfarlane, Wallace; Munson, Steve; Negron, Jose; Paine, Tim; Powell, Jim; Raffa, Kenneth; Regniere, Jacques; Reid, Mary; Romme, Bill; Seybold, Steven J.; Six, Diana; Vandygriff, Jim; Veblen, Tom; White, Mike; Witcosky, Jeff

2005-01-01

Since 1990, native bark beetles have killed billions of trees across millions of acres of forest from Alaska to northern Mexico. Although bark beetle infestations are a regular force of natural change in forested ecosystems, several of the current outbreaks, which are occurring simultaneously across western North America, are the largest and most severe in recorded history.

Nanoindentation methods for wood-adhesive bond lines

Treesearch

Joseph E. Jakes; Donald S. Stone; Charles R. Frihart

2008-01-01

As an adherend, wood is structurally, chemically, and mechanically more complex than metals or plastics, and the largest source of this complexity is wood’s chemical and mechanical inhomogeneities. Understanding and predicting the performance of adhesively bonded wood requires knowledge of the interactions occurring at length scales ranging from the macro down to the...

Exploring folate diversity in wild and primitive potatoes for modern crop improvement

USDA-ARS?s Scientific Manuscript database

Malnutrition is one of the world’s largest health concerns. Folate (a.k.a. vitamin B9) is essential in the human diet and without adequate folate intake several serious health concerns such as congenital birth defects and an increased risk of stroke and heart disease can occur. Most people’s folate ...

Visceral mast cell tumor in a captive black jaguar (Panthera onca).

PubMed

de Castro, Márcio Botelho; Werther, Karin; Godoy, Guilherme Sellera; Borges, Vivian Palmeira; Alessi, Antonio Carlos

2003-03-01

Little is known about neoplasia in the jaguar (Panthera onca), the largest American feline. A captive black jaguar was diagnosed at necropsy with a mastocytic form of visceral mast cell tumor similar to that which occurs in domestic cats. This animal had no previous clinical disease and died during anesthesia for a routine dental treatment.

Family Characteristics, Custody Arrangements, and Adolescent Psychological Well-Being after Lesbian Mothers Break up

ERIC Educational Resources Information Center

Gartrell, Nanette; Bos, Henny; Peyser, Heidi; Deck, Amalia; Rodas, Carla

2011-01-01

As part of the largest, longest running prospective American study of same-sex parent families, the present investigation examined relationship dissolution in planned lesbian families. Data were collected from 40 separated couples and their 17-year-old adolescent offspring--19 girls and 21 boys. Nearly all breakups occurred before the former…

West Nile Virus Outbreak in Houston and Harris County, Texas, USA, 2014.

PubMed

Martinez, Diana; Murray, Kristy O; Reyna, Martin; Arafat, Raouf R; Gorena, Roberto; Shah, Umair A; Debboun, Mustapha

2017-08-01

Since 2002, West Nile virus (WNV) has been detected every year in Houston and the surrounding Harris County, Texas. In 2014, the largest WNV outbreak to date occurred, comprising 139 cases and causing 2 deaths. Additionally, 1,286 WNV-positive mosquito pools were confirmed, the most reported in a single mosquito season.

Periodical Cicada--Brood V (Pest Alert)

Treesearch

USDA Forest Service

1999-01-01

Three separate species of periodical cicadas, Magicicada septendecim (L.), M. cassini (Fisher), and M. septendecula (Alexander and Moore), will appear this spring over large portions of Ohio and West Virginia during the scheduled Brood V emergence. This brood is the largest that occurs in either state and was last seen in 1982. It will also emerge in the southwest...

HYDROGEOLOGICAL AND GEOCHEMICAL FACTORS INFLUENCING MERCURY FATE AND TRANSPORT AT THE SULPHUR BANK MERCURY MINE, LAKE COUNTY, CALIFORNIA

EPA Science Inventory

Clear Lake, located approximately 150 km north of San Francisco in Lake County, is one of the largest fresh water lakes in the California. Elevated mercury levels were first identified in fish from Clear Lake in the late 1970s and early 1980s. Although naturally occurring mercury...

Threatened fishes of the world: Alosa alabamae (Jordan and Evermann, 1896) (Clupeidae)

Treesearch

Dwayne W. Meadows; Susan B. Adams; Jacob F. Schaefer

2007-01-01

River drainage to the Suwannee River, Florida (Mettee and O'Neil 2003); extirpated from at least 8 of the 14 native states (Mettee and O'Neil 2003). Abundance: Once commercially harvested, now rare (Mettee and O'Neil 2003); largest remaining population occurs in the Apalachicola River, Florida (Barku-100 et a!. 1993). Habitat...

Temperature measurements during high flux ion beam irradiations

DOE PAGES

Crespillo, Miguel L.; Graham, Joseph T.; Zhang, Yanwen; ...

2016-02-16

A systematic study of the ion beam heating effect was performed in a temperature range of –170 to 900 °C using a 10 MeV Au 3+ ion beam and a Yttria stabilized Zirconia (YSZ) sample at a flux of 5.5 × 10 12 cm –2 s –1. Different geometric configurations of beam, sample, thermocouple positioning, and sample holder were compared to understand the heat/charge transport mechanisms responsible for the observed temperature increase. The beam heating exhibited a strong dependence on the background (initial) sample temperature with the largest temperature increases occurring at cryogenic temperatures and decreasing with increasing temperature. Comparisonmore » with numerical calculations suggests that the observed heating effect is, in reality, a predominantly electronic effect and the true temperature rise is small. Furthermore, a simple model was developed to explain this electronic effect in terms of an electrostatic potential that forms during ion irradiation. Such an artificial beam heating effect is potentially problematic in thermostated ion irradiation and ion beamanalysis apparatus, as the operation of temperature feedback systems can be significantly distorted by this effect.« less

Space weather, socioeconomic factors, water quality and suicide in northwestern Russia

NASA Astrophysics Data System (ADS)

Kasatkina, Elena; Shumilov, Oleg; Novikova, Tatiana; Sutinen, Marja-Liisa; Chramov, Alexey

2013-04-01

Temporal variations in suicide occurrence in the town of Kirovsk (Kola peninsula, Murmansk region) earlier have been associated with geomagnetic disturbances (Kasatkina et al., GRA, V. 13, EGU20111630). Data on a total of 908 suicides were analyzed for the period from 1948 to 2010. The largest number of suicides occurred in 1949 (70.3 persons per 100 thousand people) and the smallest one occurred in 1985 (15.2). We have identified three maxima in the seasonal distribution of the number of suicides (March-May (P<0.001), July (P<0.01), October (P<0.001)), which coincide with maxima in the distribution of the most intense (Ap>150 nT) magnetic storms. Here we carried out the comparison of suicide occurrence temporal variations for three different towns of Murmansk region (Kirovsk, Apatity and Monchegorsk) depending on their drinking water content. Among Arctic regions, Kola peninsula is the most densely populated and industrially developed. The largest apatite-nepheline enterprise in Europe and Russia - "Apatit" is located close to the towns Kirovsk (67.6N, 33.7E) and Apatity (67.6N, 33.4E). The largest Russian nickel-copper plant "Severonikel" is located in the town of Monchegorsk (67.9N, 32.9E). In spite of some similarities of the suicide temporal trends, one can detect some differences. These differences, as we supposed, are connected to different content in drinking water of such metals as copper (Cu) and aluminum (Al). These elements may influence the incidence of mental disorders such as schizophrenia, senile dementia and Wilson's disease.

Hydrologic conditions and hazards in the Kennicott River basin, Wrangell-St. Elias National Park Preserve, Alaska

USGS Publications Warehouse

Rickman, R.L.; Rosenkrans, D.S.

1997-01-01

McCarthy, Alaska, is on the Kennicott River, about 1 mile from the terminus of Kennicott Glacier in the Wrangell-St. Elias National Park and Preserve. Most visitors to McCarthy and the park cross the West Fork Kennicott River using a hand-pulled tram and cross the East Fork Kennicott River on a temporary footbridge. Outburst floods from glacier-dammed lakes result in channel erosion, aggradation, and migration of the Kennicott River, which disrupt transportation links, destroy property, and threaten life. Hidden Creek Lake, the largest of six glacier-dammed lakes in the Kennicott River Basin, has annual outbursts that cause the largest floods on the Kennicott River. Outbursts from Hidden Creek Lake occur from early fall to mid-summer, and lake levels at the onset of the outbursts have declined between 1909 and 1995. Criteria for impending outbursts for Hidden Creek Lake include lake stage near or above 3,000 to 3,020 feet, stationary or declining lake stage, evidence of recent calving of large ice blocks from the ice margin, slush ice and small icebergs stranded on the lakeshore, and fresh fractures in the ice-margin region. The lower Kennicott Glacier has thinned and retreated since about 1860. The East and West Fork Kennicott River channels migrated in response to changes in the lower Kennicott Glacier. The largest channel changes occur during outburst floods from Hidden Creek Lake, whereas channel changes from the other glacier-dammed lake outbursts are small. Each year, the West Fork Kennicott River conveys a larger percentage of the Kennicott Glacier drainage than it did the previous year. Outburst floods on the Kennicott River cause the river stage to rise over a period of several hours. Smaller spike peaks have a very rapid stage rise. Potential flood magnitude was estimated by combining known maximum discharges from Hidden Creek Lake and Lake Erie outburst floods with a theoretical large regional flood. Flood hazard areas at the transportation corridor were delineated, and possible future geomorphological changes were hypothesized. McCarthy, Alaska, is on the Kennicott River, about 1 mile from the terminus of Kennicott Glacier in the Wrangell-St. Elias National Park and Preserve. Most visitors to McCarthy and the park cross the West Fork Kennicott River using a hand-pulled tram and cross the East Fork Kennicott River on a temporary footbridge. Outburst floods from glacier-dammed lakes result in channel erosion, aggradation, and migration of the Kennicott River, which disrupt transportation links, destroy property, and threaten life. Hidden Creek Lake, the largest of six glacier-dammed lakes in the Kennicott River Basin, has annual outbursts that cause the largest floods on the Kennicott River. Outbursts from Hidden Creek Lake occur from early fall to mid-summer, and lake levels at the onset of the outbursts have declined between 1909 and 1995. Criteria for impending outbursts for Hidden Creek Lake include lake stage near or above 3,000 to 3,020 feet, stationary or declining lake stage, evidence of recent calving of large ice blocks from the ice margin, slush ice and small icebergs stranded on the lakeshore, and fresh fractures in the ice-margin region. The lower Kennicott Glacier has thinned and retreated since about 1860. The East and West Fork Kennicott River channels migrated in response to changes in the lower Kennicott Glacier. The largest channel changes occur during outburst floods from Hidden Creek Lake, whereas channel changes from the other glacier-dammed lake outbursts are small. Each year, the West Fork Kennicott River conveys a larger percentage of the Kennicott Glacier drainage than it did the previous year. Outburst floods on the Kennicott River cause the river stage to rise over a period of several hours. Smaller spike peaks have a very rapid stage rise. Potential flood magnitude was estimated by combining known maximum discharges from Hidden Creek Lake and Lake Erie outburst floods with

Differences Between Magnitudes and Health Impacts of BC ...

EPA Pesticide Factsheets

Recent assessments have analyzed the health impacts of PM2.5 from emissions from different locations and sectors using simplified or reduced-form air quality models. Here we present an alternative approach using the adjoint of the Community Multiscale Air Quality (CMAQ) model, which provides source–receptor relationships at highly resolved sectoral, spatial, and temporal scales. While damage resulting from anthropogenic emissions of BC is strongly correlated with population and premature death, we found little correlation between damage and emission magnitude, suggesting that controls on the largest emissions may not be the most efficient means of reducing damage resulting from anthropogenic BC emissions. Rather, the best proxy for locations with damaging BC emissions is locations where premature deaths occur. Onroad diesel and nonroad vehicle emissions are the largest contributors to premature deaths attributed to exposure to BC, while onroad gasoline emissions cause the highest deaths per amount emitted. Emissions in fall and winter contribute to more premature deaths (and more per amount emitted) than emissions in spring and summer. Overall, these results show the value of the high-resolution source attribution for determining the locations, seasons, and sectors for which BC emission controls have the most effective health benefits. The National Exposure Research Laboratory’s Atmospheric Modeling Division (AMAD) conducts research in support of EPA’s mis

Factors influencing development of cracking-sliding failures of loess across the eastern Huangtu Plateau of China

NASA Astrophysics Data System (ADS)

Li, Yanrong; Mao, Jiarui; Xiang, Xiqiong; Mo, Ping

2018-04-01

Loess is a porous, weakly cemented, and unsaturated Quaternary sediment deposited by the wind in arid and semiarid regions. Loess is widely and thickly distributed in China, making the Huangtu Plateau the largest bulk accumulation of loess on Earth. However, the fragile geoenvironment in the loess areas of China causes frequent and various geohazards, such as cracking-sliding failure (beng-hua in Chinese), which is a typical geohazard that causes the largest number of casualties each year. This study investigates the main influencing factors and development patterns of cracking-sliding failure of loess to help prevent its occurrence and reduce losses effectively. The following conclusions are derived from this study: (1) cracking-sliding failures mostly take place in rectilinear slopes, convex slopes, slopes with gradients greater than 60°, slopes with heights of 5 to 40 m, and slopes mostly exposed to sunlight with aspects of 180 to 270°; (2) cracking-sliding failures occur mostly from 10 pm to 4 am and mainly in the rainy season (July to September) and in the freeze-thaw season (March to April); and (3) highly intense human activities in the region correspond to a high possibility of cracking-sliding failures.

Conservation of Terrestrial Vertebrates in a Global Hotspot of Karst Area in Southwestern China

PubMed Central

Luo, Zhenhua; Tang, Songhua; Jiang, Zhigang; Chen, Jing; Fang, Hongxia; Li, Chunwang

2016-01-01

The karst area of southwest China (KASC) is the largest piece of karst landscape on the earth and a global biodiversity hot-spot with high concentrations of endemic species. Although a number of nature reserves (NRs) have been established across the region, the representativeness of biodiversity of the NR system is still unknown. Based on comprehensive literature and field surveys, and intensive consultations with zoologists and wildlife managers, we compiled distributions of 1,204 terrestrial vertebrate species and 271 NRs in KASC. We found Jinxiu, Mengla, Hekou, and Jinghong have the richest amphibian species; Jinxiu has the highest species richness of reptiles; Jinghong, Menghai, and Mengla have the largest numbers of avian species; whereas, Mengla, Longzhou, and Ningming have the greatest mammalian diversity in the region. Gap analysis among NR system, species richness pattern, and five biogeographic indicators found insufficient representation of the NR system on territorial vertebrate diversity. The conservation effectiveness in Guizhou Province was much lower than that in Guangxi and Yunnan Provinces. Under-representation and over-representation simultaneously occurred in many of the ecoregions, elevation classes, vegetation types, landcover categories, and human disturbance intensity gradients. For conservation of terrestrial vertebrates in KASC, several suggestions were presented in this study. PMID:27228463

Conservation of Terrestrial Vertebrates in a Global Hotspot of Karst Area in Southwestern China.

PubMed

Luo, Zhenhua; Tang, Songhua; Jiang, Zhigang; Chen, Jing; Fang, Hongxia; Li, Chunwang

2016-05-26

The karst area of southwest China (KASC) is the largest piece of karst landscape on the earth and a global biodiversity hot-spot with high concentrations of endemic species. Although a number of nature reserves (NRs) have been established across the region, the representativeness of biodiversity of the NR system is still unknown. Based on comprehensive literature and field surveys, and intensive consultations with zoologists and wildlife managers, we compiled distributions of 1,204 terrestrial vertebrate species and 271 NRs in KASC. We found Jinxiu, Mengla, Hekou, and Jinghong have the richest amphibian species; Jinxiu has the highest species richness of reptiles; Jinghong, Menghai, and Mengla have the largest numbers of avian species; whereas, Mengla, Longzhou, and Ningming have the greatest mammalian diversity in the region. Gap analysis among NR system, species richness pattern, and five biogeographic indicators found insufficient representation of the NR system on territorial vertebrate diversity. The conservation effectiveness in Guizhou Province was much lower than that in Guangxi and Yunnan Provinces. Under-representation and over-representation simultaneously occurred in many of the ecoregions, elevation classes, vegetation types, landcover categories, and human disturbance intensity gradients. For conservation of terrestrial vertebrates in KASC, several suggestions were presented in this study.

Evidence of indiscriminate fishing effects in one of the world's largest inland fisheries.

PubMed

Ngor, Peng Bun; McCann, Kevin S; Grenouillet, Gaël; So, Nam; McMeans, Bailey C; Fraser, Evan; Lek, Sovan

2018-06-12

While human impacts like fishing have altered marine food web composition and body size, the status of the world's important tropical inland fisheries remains largely unknown. Here, we look for signatures of human impacts on the indiscriminately fished Tonle Sap fish community that supports one of the world's largest freshwater fisheries. By analyzing a 15-year time-series (2000-2015) of fish catches for 116 species obtained from an industrial-scale 'Dai' fishery, we find: (i) 78% of the species exhibited decreasing catches through time; (ii) downward trends in catches occurred primarily in medium to large-bodied species that tend to occupy high trophic levels; (iii) a relatively stable or increasing trend in catches of small-sized species, and; (iv) a decrease in the individual fish weights and lengths for several common species. Because total biomass of the catch has remained remarkably resilient over the last 15 years, the increase in catch of smaller species has compensated for declines in larger species. Our finding of sustained production but altered community composition is consistent with predictions from recent indiscriminate theory, and gives a warning signal to fisheries managers and conservationists that the species-rich Tonle Sap is being affected by heavy indiscriminate fishing pressure.

Nonlinear anelastic modal theory for solar convection

NASA Technical Reports Server (NTRS)

Latour, J.; Toomre, J.; Zahn, J.-P.

1983-01-01

Solar envelope models are developed using single-mode anelastic equations as a description of turbulent convection which provide estimates for the variation with depth of the largest convective cellular flows, with horizontal sizes comparable to the total depth of the convection zone. These models can be used to describe compressible motions occurring over many density scale heights. Single-mode anelastic solutions are obtained for a solar envelope whose mean stratification is nearly adiabatic over most of its vertical extent because of the enthalpy flux explicitly carried by the big cell, while a subgrid scale representation of turbulent heat transport is incorporated into the treatment near the surface. It is shown that the single-mode equations allow two solutions for the same horizontal wavelength which are distinguished by the sense of the vertical velocity at the center of the three-dimensional cell. It is found that the upward directed flow experiences large pressure effects which can modify the density fluctuations so that the sense of the buoyancy force is changed, with buoyancy braking actually achieved near the top of the convection zone. It is suggested that such dynamical processes may explain why the amplitudes of flows related to the largest scales of convection are so weak in the solar atmosphere.

Time-dependent gravity in Southern California, May 1974 to April 1979

NASA Technical Reports Server (NTRS)

Whitcomb, J. H.; Franzen, W. O.; Given, J. W.; Pechmann, J. C.; Ruff, L. J.

1980-01-01

The Southern California gravity survey, begun in May 1974 to obtain high spatial and temporal density gravity measurements to be coordinated with long-baseline three dimensional geodetic measurements of the Astronomical Radio Interferometric Earth Surveying project, is presented. Gravity data was obtained from 28 stations located in and near the seismically active San Gabriel section of the Southern California Transverse Ranges and adjoining San Andreas Fault at intervals of one to two months using gravity meters relative to a base station standard meter. A single-reading standard deviation of 11 microGal is obtained which leads to a relative deviation of 16 microGal between stations, with data averaging reducing the standard error to 2 to 3 microGal. The largest gravity variations observed are found to correlate with nearby well water variations and smoothed rainfall levels, indicating the importance of ground water variations to gravity measurements. The largest earthquake to occur during the survey, which extended to April, 1979, is found to be accompanied in the station closest to the earthquake by the largest measured gravity changes that cannot be related to factors other than tectonic distortion.

Uncovering the Internal Structure of the Indian Financial Market: Large Cross-correlation Behavior in the NSE

NASA Astrophysics Data System (ADS)

Sinha, Sitabhra; Pan, Raj Kumar

The cross-correlations between price fluctuations of 201 frequently traded stocks in the National Stock Exchange (NSE) of India are analyzed in this paper. We use daily closing prices for the period 1996-2006, which coincides with the period of rapid transformation of the market following liberalization. The eigenvalue distribution of the cross-correlation matrix, C, of NSE is found to be similar to that of developed markets, such as the New York Stock Exchange (NYSE): the majority of eigenvalues fall within the bounds expected for a random matrix constructed from mutually uncorrelated time series. Of the few largest eigenvalues that deviate from the bulk, the largest is identified with market-wide movements. The intermediate eigenvalues that occur between the largest and the bulk have been associated in NYSE with specific business sectors with strong intra-group interactions. However, in the Indian market, these deviating eigenvalues are comparatively very few and lie much closer to the bulk. We propose that this is because of the relative lack of distinct sector identity in the market, with the movement of stocks dominantly influenced by the overall market trend. This is shown by explicit construction of the interaction network in the market, first by generating the minimum spanning tree from the unfiltered correlation matrix, and later, using an improved method of generating the graph after filtering out the market mode and random effects from the data. Both methods show, compared to developed markets, the relative absence of clusters of co-moving stocks that belong to the same business sector. This is consistent with the general belief that emerging markets tend to be more correlated than developed markets.

Static stress drop of the largest recorded M 4.6 hydraulic fracturing induced earthquake and its aftershock pattern in the northern Montney Play, British Columbia, Canada

NASA Astrophysics Data System (ADS)

Wang, B.; Harrington, R. M.; Liu, Y.; Kao, H.

2016-12-01

The largest suspected fracking-induced earthquake to date occurred near Fort St. John, British Columbia on August 17, 2015, with a reported magnitude of Mw 4.6. Here we estimate the static stress released by the mainshock and the five cataloged aftershocks using new data from eight broadband seismometers installed approximately 50km from the hypocenter of the mainshock, at distances much closer than the Natural Resources Canada regional seismic stations. The estimated cross-correlation coefficient among the 5 cataloged earthquakes is 0.35 or greater. We will present seismic moment (M0) and spectral corner frequency (fc) values estimated using both individual earthquake spectra and spectral ratios to correct for travel-path attenuation and site effects. Static stress drop and scaled energy value calculations based on the estimated moment and corner frequency values will be presented, as well as focal mechanisms for the largest events with adequate station coverage. We will also use a multi-station matched-filter approach to detect additional uncataloged earthquakes on continuous waveforms for a period of two months after the mainshock. Using the results of the matched-filter approach, we will present the aftershock magnitude distribution and locations. The results of our detection and location calculations will be compared to reported fracking parameters, such as fluid injection pressure and duration, to determine their correlation with the spatial and temporal distribution of aftershocks. The objective of this study is to relate operational parameters to earthquake occurrence in order to help to develop procedures to understand the mechanisms responsible for fracking induced earthquakes, their relation to the maximum induced magnitude, and to reduce potential hazards of anthropogenically induced seismic activity.

The local time dependence of the anisotropic solar cosmic ray flux.

PubMed

Smart, D F; Shea, M A

2003-01-01

The distribution of the solar cosmic radiation flux over the earth is not uniform, but the result of complex phenomena involving the interplanetary magnetic field, the geomagnetic field and latitude and longitude of locations on the earth. The latitude effect relates to the geomagnetic shield; the longitude effect relates to local time. For anisotropic solar cosmic ray events the maximum particle flux is always along the interplanetary magnetic field direction, sometimes called the Archimedean spiral path from the sun to the earth. During anisotropic solar cosmic ray event, the locations on the earth viewing "sunward" into the interplanetary magnetic field direction will observe the largest flux (when adjustments are made for the magnetic latitude effect). To relate this phenomena to aircraft routes, for anisotropic solar cosmic ray events that occur during "normal quiescent" conditions, the maximum solar cosmic ray flux (and corresponding solar particle radiation dose) will be observed in the dawn quadrant, ideally at about 06 hours local time. Published by Elsevier Ltd on behalf of COSPAR.

Effects of spanwise blowing on the pressure field and vortex-lift characteristics of a 44 deg swept trapezoidal wing. [wind tunnel stability tests - aircraft models

NASA Technical Reports Server (NTRS)

Campbell, J. F.

1975-01-01

Wind-tunnel data were obtained at a free-stream Mach number of 0.26 for a range of model angle of attack, jet thrust coefficient, and jet location. Results of this study show that the sectional effects to spanwise blowing are strongly dependent on angle of attack, jet thrust coefficient, and span location; the largest effects occur at the highest angles of attack and thrust coefficients and on the inboard portion of the wing. Full vortex lift was achieved at the inboard span station with a small blowing rate, but successively higher blowing rates were necessary to achieve full vortex lift at increased span distances. It is shown that spanwise blowing increases lift throughout the angle-of-attack range, delays wing stall to higher angles of attack, and improves the induced-drag polars. The leading-edge suction analogy can be used to estimate the section and total lifts resulting from spanwise blowing.

An experimental investigation of S-duct flow control using arrays of low-profile vortex generators

NASA Technical Reports Server (NTRS)

Reichert, Bruce A.; Wendt, Bruce J.

1993-01-01

An experimental investigation was undertaken to measure the effect of various configurations of low-profile vortex generator arrays on the flow in a diffusing S-duct. Three parameters that characterize the vortex generator array were systematically varied to determine their effect: (1) the vortex generator height; (2) the streamwise location of the vortex generator array; and (3) the vortex generator spacing. Detailed measurements of total pressure at the duct exit, surface static pressure, and surface flow visualization were gathered for each vortex generator configuration. These results are reported here along with total pressure recovery and distortion coefficients determined from the experimental data. Each array of vortex generators tested improved total pressure recovery. The configuration employing the largest vortex generators was the most effective in reducing total pressure recovery. No configuration of vortex generators completely eliminated the flow separation that naturally occurs in the S-duct, however the extent of the separated flow region was reduced.

Long Term Follow-up of Botulinum Toxin Therapy for Focal Hand Dystonia: Outcome at 10 or More Years

PubMed Central

Lungu, Codrin; Karp, Barbara I; Alter, Katharine; Zolbrod, Regina; Hallett, Mark

2010-01-01

Background Prior studies have explored the efficacy and safety of BoNT treatment for FHD, but none have followed a large number of patients for 10 or more years. Methods Retrospective study, with benefit and weakness assessed on a 0-4 subjective scale. Demographic, clinical and treatment characteristics were analyzed using t-tests and Pearson correlations. Results 20 FHD patients had 10 years or longer treatment. Inter-injection intervals were variable. Musicians were more likely to wait longer between injections and had less complex dystonia. There was a trend for larger benefit in women and with shorter intervals. The dose increased over time. Dystonia characteristics did not predict response or side-effects, but benefit magnitude predicted longer compliance. No serious side-effects or antibody-mediated resistance occurred. Conclusion This is the longest reported period of BoNT treatment in the largest FHD cohort. BoNT therapy for FHD remains safe and effective after more than a decade of treatment. PMID:21506157

Effects of Sediment Containing Coal Ash from the Kingston Ash Release on Embryo-Larval Development in the Fathead Minnow, Pimephales promelas (Rafinesque, 1820)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Greeley Jr, Mark Stephen; Elmore, Logan R; McCracken, Kitty

2014-01-01

The largest environmental release of coal ash in U.S. history occurred in December 2008 with the failure of a retention structure at the Tennessee Valley Authority (TVA) Kingston Fossil Plant in East Tennessee. A byproduct of coal-burning power plants, coal ash is enriched in metals and metalloids such as selenium and arsenic with known toxicity to fish including embryonic and larval stages. The effects of contact exposure to sediments containing up to 78 % coal ash from the Kingston spill on the early development of fish embryos and larvae were examined in 7-day laboratory tests with the fathead minnow (Pimephalesmore » promelas). No significant effects were observed on hatching success, incidences of gross developmental abnormalities, or embryo-larval survival. Results suggest that direct exposures to sediment containing residual coal ash from the Kingston ash release may not present significant risks to fish eggs and larvae in waterways affected by the spill.« less

Does boat traffic cause displacement of fish in estuaries?

PubMed

Becker, Alistair; Whitfield, Alan K; Cowley, Paul D; Järnegren, Johanna; Næsje, Tor F

2013-10-15

Estuaries are increasingly under threat from a variety of human impacts. Recreational and commercial boat traffic in urban areas may represent a significant disturbance to fish populations and have particularly adverse effects in spatially restricted systems such as estuaries. We examined the effects of passing boats on the abundance of different sized fish within the main navigation channel of an estuary using high resolution sonar (DIDSON). Both the smallest (100-300 mm) and largest (>501 mm) size classes had no change in their abundance following the passage of boats. However, a decrease in abundance of mid-sized fish (301-500 mm) occurred following the passage of boats. This displacement may be attributed to a number of factors including noise, bubbles and the rapidly approaching object of the boat itself. In highly urbanised estuarine systems, regular displacement by boat traffic has the potential to have major negative population level effects on fish assemblages. Copyright © 2013 Elsevier Ltd. All rights reserved.

Influence of a dominant consumer species reverses at increased diversity.

PubMed

Brandt, Margarita; Witman, Jon D; Chiriboga, Angel I

2012-04-01

Theory and experiments indicate that changes in consumer diversity affect benthic community structure and ecosystem functioning. Although the effects of consumer diversity have been tested in the laboratory and the field, little is known about effects of consumer diversity in the subtidal zone, one of the largest marine habitats. We investigated the grazing effects of sea urchins on algal abundance and benthic community structure in a natural subtidal habitat of the Galápagos Islands. Three species of urchins (Eucidaris, Lytechinus, and Tripneustes) were manipulated in inclusion cages following a replacement design with three levels of species richness (one, two, and three species) with all possible two-species urchin combinations. Identity was the main factor accounting for changes in the percentage of substrate grazed and benthic community structure. Two out of the three two-species assemblages grazed more than expected, suggesting a richness effect, but analyses revealed that this increased grazing was due to a sampling effect of the largest and commercially valued urchin species, Tripneustes. Benthic community structure in treatments with Eucidaris, Lytechinus, and Tripneustes alone was significantly different at the end of the experiment, suggesting that resource use differentiation occurred. Communities in Tripneustes enclosures were characterized by abundant crustose coralline algae and grazed substrate, while those without it contained abundant green foliose algae (Ulva sp.). An unexpected emergent property of the system was that the most species-rich urchin assemblage underyielded, grazing less than any other assemblage with Tripneustes, effectively reversing its dominant influence observed in the two-species treatments. While further experiments are needed to discern the mechanisms of underyielding, it may be related to changing interspecific interactions as richness increases from two to three species or to density-dependent Tripneustes grazing. This study highlights the general importance of evaluating consumer richness effects across the entire range of species richness considered, as the performance of the most species-rich consumer assemblage could not be predicted by manipulations of intermediate levels of consumer species richness.

Population dynamics of plant nematodes in cultivated soil: length of rotation in newly cleared and old agricultural land.

PubMed

Good, J M; Murphy, W S; Brodie, B B

1973-04-01

During a 6-year study of 1-, 2-, and 3-year crop rotations, population densities of Pratylenchus brachyurus, Trichodorus christiei, and Meloidogyne incognita were significantly affected by the choice of crops but not by length of crop rotation. The density of P. brachyurus and T. christiei increased rapidly on milo (Sorghum vulgate). In addition, populations of P. brachyurus increased significantly in cropping systems that involved crotalaria (C. rnucronata), millet (Setaria italica), and sudangrass (Sorghum sudanense). Lowest numbers of P. brachyurus occurred where okra (Hibiscus esculentus) was grown or where land was fallow. The largest increase in populations of T. christiei occurred in cropping systems that involved millet, sudangrass, and okra whereas the smallest increase occurred in cropping systems that involved crotalaria or fallow. A winter cover of rye (Secale cereale) had no distinguishable effect on population densities of P. brachyurus or T. christiei. Meloidogyne incognita was detected during the fourth year in both newly cleared and old agricultural land when okra was included in the cropping system. Detectable populations of M. incognita did not develop in any of the other cropping systems. Yields of tomato transplants were higher on the newly cleared land than on the old land. Highest yields were obtained when crotalaria was included in the cropping system. Lowest yields were obtained when milo, or fallow were included in the cropping system. Length of rotation had no distinguishable effect on yields of tomato transplants.

Potentially induced earthquakes in Oklahoma, USA: links between wastewater injection and the 2011 Mw 5.7 earthquake sequence

USGS Publications Warehouse

Keranen, Katie M.; Savage, Heather M.; Abers, Geoffrey A.; Cochran, Elizabeth S.

2013-01-01

Significant earthquakes are increasingly occurring within the continental interior of the United States, including five of moment magnitude (Mw) ≥ 5.0 in 2011 alone. Concurrently, the volume of fluid injected into the subsurface related to the production of unconventional resources continues to rise. Here we identify the largest earthquake potentially related to injection, an Mw 5.7 earthquake in November 2011 in Oklahoma. The earthquake was felt in at least 17 states and caused damage in the epicentral region. It occurred in a sequence, with 2 earthquakes of Mw 5.0 and a prolific sequence of aftershocks. We use the aftershocks to illuminate the faults that ruptured in the sequence, and show that the tip of the initial rupture plane is within ~200 m of active injection wells and within ~1 km of the surface; 30% of early aftershocks occur within the sedimentary section. Subsurface data indicate that fluid was injected into effectively sealed compartments, and we interpret that a net fluid volume increase after 18 yr of injection lowered effective stress on reservoir-bounding faults. Significantly, this case indicates that decades-long lags between the commencement of fluid injection and the onset of induced earthquakes are possible, and modifies our common criteria for fluid-induced events. The progressive rupture of three fault planes in this sequence suggests that stress changes from the initial rupture triggered the successive earthquakes, including one larger than the first.

Effects of Nuclear Cross Sections at Different Energies on the Radiation Hazard from Galactic Cosmic Rays

NASA Technical Reports Server (NTRS)

Lin, Z. W.; Adams, J. H., Jr.

2006-01-01

The radiation hazard for astronauts from galactic cosmic rays is a major obstacle in long duration human space explorations. Space radiation transport codes have been developed to calculate radiation environment on missions to the Moon, Mars or beyond. We have studied how uncertainties in fragmentation cross sections at different energies affect the accuracy of predictions from such radiation transport. We find that, in deep space, cross sections between 0.3 and 0.85 GeV/u usually have the largest effect on dose-equivalent behind shielding in solar minimum GCR environments, and cross sections between 0.85 and 1.2 GeV/u have the largest effect in solar maximum GCR environments. At the International Space Station, cross sections at higher energies have the largest effect due to the geomagnetic cutoff.

Colony impact of pesticide-induced sublethal effects on honeybee workers: A simulation study using BEEHAVE.

PubMed

Thorbek, Pernille; Campbell, Peter J; Thompson, Helen M

2017-03-01

Research on neonicotinoids and honeybees have changed focus from direct mortality to sublethal effects. In the present study, a published honeybee model, BEEHAVE, is used to compare induced colony level impact of pesticides including direct mortality, poor brood care, disorientation, and increased handling time in oilseed rape and sunflower crops. Actual effects on individual bees will depend on exposure concentrations, but in the present study large effects were enforced. In oilseed rape, poor brood care had the largest colony impact, because it created a bottleneck for spring build-up of the workforce, and colony impact for all effect types peaked 1 mo after exposure ceased. In sunflower, the later exposure changed the response so colony impact peaked during exposure, and the bottleneck was honey store build-up. In all scenarios, good forage mitigated effects substantially. It is concluded that field studies should continue at least 1 mo after exposure to ensure detection of ecologically relevant sublethal effects. The results indicated that even if a sublethal effect is difficult to detect in the field, subsequent ecologically relevant colony level impacts would be clear if studies are continued for 1 mo after exposure. Guidance for regulatory studies recommends extended observation periods, and published field studies already use extended observation periods, so it is concluded that current methods are adequate for detecting ecologically relevant sublethal effects. Although published laboratory and semifield studies conducted under controlled exposure conditions suggest that sublethal effects may occur, published field studies with neonicotinoid seed treatments, naturally foraging bees, and extended observation periods do not report colony-level effects, suggesting that in these studies no ecologically relevant sublethal effects occurred. Environ Toxicol Chem 2017;36:831-840. © 2016 SETAC. © 2016 SETAC.

Evaluation of water quality, suspended sediment, and stream morphology with an emphasis on effects of stormwater on Fountain and Monument Creek basins, Colorado Springs and vicinity, Colorado, 1981-2001

USGS Publications Warehouse

Edelmann, Patrick; Ferguson, Sheryl A.; Stogner, Sr., Robert W.; August, Marianne; Payne, William F.; Bruce, James F.

2002-01-01

This report documents water quality and suspended sediment with an emphasis on evaluating the effects of stormflow on Fountain Creek Basin in the vicinity of Colorado Springs, Colorado. Water-quality data collected at 11 sites between 1981 and 2001 were used to evaluate the effects of stormflow on water quality. Suspended-sediment data collected at seven sites from 1998 through 2001 were used to evaluate effects of stormflow on suspended-sediment concentrations, discharges, and yields. Data were separated into three flow regimes: base flow, normal flow, and stormflow. A comparison of stormwater-quality concentrations measured between 1981 and 2001 to Colorado acute instream standards indicated that, except for isolated occurrences, stormwater quality met acute instream standards. At several sites, 5-day biochemical oxygen demand, fecal coliform, and selected nutrient concentrations tended to be highest during stormflow and lowest during base flow. Dissimilar to the other nutrients, dissolved nitrite plus nitrate concentrations generally were highest during base flow and lowest during stormflow. Most dissolved trace-element concentrations associated with stormflow decreased or showed little change compared to base flow. However, median concentrations of total copper, iron, lead, nickel, manganese, and zinc for stormflow samples generally were much larger than nonstorm samples. The substantially larger concentrations of total copper, iron, lead, nickel, manganese, and zinc measured at site 5800 during stormflow as compared to other sites indicates a relatively large source of these metals in the reach between sites 5530 and 5800. Semi-volatile organic compounds in samples collected during stormflow were detected relatively infrequently at the four sites monitored; however, analysis of pesticide data collected during stormflow showed a relatively frequent detection of pesticides at low levels. Nitrogen, phosphorus, and particulate trace-element loads substantially increased during stormflow. Suspended-sediment concentrations, discharges, and yields associated with stormflow were significantly greater than during normal flow. Depending on the site and year, suspended-sediment concentrations associated with storm-flow generally were 3 to10 times greater than concentrations measured during normal flow, and suspended-sediment discharges were usually more than 10 times greater during stormflow. The April through October cumulative suspended-sediment discharges and streamflows were largest in 1999 at all sites. Although large spatial variations in suspended-sediment yields occurred during normal flows, the suspended-sediment yields associated with stormflow generally were more than 10 times greater than the suspended-sediment yields that occurred during normal flow. The smallest suspended-sediment yields generally were less than 1 ton per day per square mile during stormflow. The largest suspended-sediment yields occurred at sites located in the Cottonwood Creek Basin and were greater than 10 tons per day per square mile.

Post ablation recanalization of varicose veins of the limbs: Comparison ablation method of mechanochemical and laser procedure

NASA Astrophysics Data System (ADS)

Suhartono, R.; Irfan, W.; Wangge, G.; Moenadjat, Y.; Destanto, W. I.

2017-08-01

Endovenous ablation has been performed for varicose veins of the limbs in Indonesia since 2010. Endovenous laser ablation (EVLA) therapy has been performed in Cipto Mangunkusumo Hospital (RSCM) in Jakarta, and mechanochemical ablation (MOCA) has been conducted in Fatmawati Hospital. This was a descriptive analytical study, with a cross-sectional design to analyze post-ablation recanalization after MOCA and EVLA procedures. Patients who had undergone MOCA or EVLA treatment were interviewed 3-18 months after the procedures. All the patients underwent vascular ultrasonography (USG) of the operated limb to assess recanalization. Secondary presurgery data were obtained from the patients’ from patients’ medical records. The clinical characteristics of the subjects were recorded to compare the potential correlation between these characteristics and recanalization post-MOCA and EVLA procedures. All the data were analyzed using SPSS ver. 20.0. The study consisted of 43 limbs: 24 treated by MOCA and 19 treated by EVLA. Most subjects in the MOCA group were <60 years (20/24), and 16 of the subjects were women. In the EVLA group, nine patients were <60 years, and 19 were ≥60 years, 15 of whom were women. The body mass index (BMI) of the majority (18/24) of the subjects in the MOCA group was normal, whereas most of the patients in the EVLA (10/19) group were overweight. In the MOCA group, the largest diameter of the vena saphena magna (VSM) in 20/24 extremities prior to treatment was VSM 4-7 mm, whereas the largest diameter in the EVLA group prior to treatment was >7 mm in 13/19 extremities. In the MOCA group, total recanalization occurred in 2/24 extremities, and partial recanalization occurred in 8/24 extremities. In the EVLA group, total recanalization occurred in 1/19 extremities, and partial recanalization occurred in 3/19 extremities. The association between the clinical characteristics of the patients and recanalization was not statistically significant (p > 0.05). The recanalization tendency was higher in the MOCA group than in the EVLA group. Although there was no statistically significant association between the clinical characteristics of the patients and recanalization, the largest diameter of the VSM presurgery (>7 mm) was higher in 3/4 extremities in the MOCA group, as compared to 3/13 extremities in the EVLA group.

A Needle in a Haystack: A Search for Value for Money in Turn-Around Strategies for Schools in Difficult Circumstances

ERIC Educational Resources Information Center

Khupe, Constance; Balkwill, Kevin; Osman, Ruksana; Cameron, Ann

2013-01-01

Background: While current investments in school improvement occur in the context of the worldwide economic downturn, in the South African context, there is in addition widespread disparity in education provision and attainment related to pre-democracy race-based patterns. Despite the education sector receiving the largest national annual budget…

A resource at the crossroads: a history of the central hardwoods

Treesearch

Ray R., Jr. Hicks

1997-01-01

The Central Hardwood Forest is an oak dominated deciduous forest that stretches from Massachusetts to Arkansas and occurs in hilly to mountainous terrain. It is the largest and most extensive temperate deciduous forest in the world. During the past 20 million years or so, angiosperms have been gradually replacing gymnosperms as the dominant plant form on earth, and...

Climate Change and the Nation's Forests: Challenges and Opportunities

Treesearch

Dale Bosworth; Richard Birdsey; Linda Joyce; Constance Millar

2008-01-01

Climate change is already affecting America's forests. The fires of 2000 shocked the Nation, the fires of 2006 burned an area greater than in any year since 1954, and the 2007 fires in southern California forced the evacuation of more than a million residents. Some of the largest individual fires ever recorded in the Western United States and Alaska occurred in...

Using WEPP technology to predict erosion and runoff following wildfire

Treesearch

William J. Elliot; Ina Sue Miller; Brandon D. Glaza

2006-01-01

Erosion following wildfire can be as much as 1000 times the erosion from an undisturbed forest. In August, 2005, the largest fire in the lower 48 states occurred in the Umatilla National Forest in Southeast Washington. Researchers from the Rocky Mountain Research Station assisted the forest in estimating soil erosion using three different applications of the WEPP model...

Foliar moisture content of Pacific Northwest vegetation and its relation to wildland fire behavior.

Treesearch

James K. Agee; Clinton S. Wright; Nathan Williamson; Mark H. Huff

2002-01-01

Fotiar moisture was monitored for five conifers and associated understory vegetation in Pacific Northwest forests. Decline in foliar moisture of new foliage occurred over the dry season, while less variation was evident in older foliage. Late season foliar moisture ranged from 130 to 170%. In riparian-upland comparisons, largest differences were found for understory...

Using morphometrics to identify glochidia from a diverse freshwater mussel community

Treesearch

Thomas B. Kennedy; Wendell R. Haag

2005-01-01

We measured shell length, hinge length, and height of glochidia from 21 freshwater mussel species occurring in the Sipsey River, Alabama, to test our ability to identify species based on these glochidial morphometrics. Glochidial size and shape differed widely among species; for all 3 dimensions, mean values for the largest species were 5 to 73 greater than for the...

Teaching Primary School Children about Japan through Art. ERIC Digest.

ERIC Educational Resources Information Center

Ward, Patricia Berg

There are a variety reasons for teaching about Japan. Many students in the United States are of Japanese heritage; Japan is the second largest trading partner of the United States; and some healing still needs to occur between the United States and Japan because of the damage and pain of World War II. Further, the Unites States and Japan share the…

Retrospective review of pediatric oral lesions from a dental school biopsy service.

PubMed

Shah, Suhani K; Le, Mary C; Carpenter, William M

2009-01-01

This report presents a review of the results from 5457 biopsies of patients, 0-16 years of age, received over 15 years at the University of the Pacific School of Dentistry (Pacific Oral and Maxillofacial Pathology Laboratory). To carry out the largest and most up to date U.S. survey of oral specimens from children. The computerized data was retrieved and compiled for age and diagnoses. The lesions were divided by the MIND classification system into 1) Metabolic 2) Inflammatory 3) Neoplastic and 4) Developmental. Inflammatory lesions formed the largest group of biopsies (2758, 51%) followed by Developmental conditions (1928, 35%) and Neoplasms (734, 13%). Dentigerous cysts were the most common lesions, followed by the mucous retention phenomenon (mucocele). The 15 most frequently occurring lesions accounted for 80% of all biopsies. Eight malignancies and 22 benign aggressive tumors were also included. 1. Pathoses increase with age. 2. Results from our study are similar to most of the other studies. 3. More serious pathoses occur in some countries where there is limited access to care, resulting in patients seeking care only when symptomatic. 4. Oral malignancies are rare, but as with any malignancy, early diagnosis renders a more favorable prognosis.

Short-period atmospheric gravity waves - A study of their statistical properties and source mechanisms

NASA Technical Reports Server (NTRS)

Gedzelman, S. D.

1983-01-01

Gravity waves for the one year period beginning 19 October 1976 around Palisades, New York, are investigated to determine their statistical properties and sources. The waves have typical periods of 10 min, pressure amplitudes of 3 Pa and velocities of 30 m/s. In general, the largest, amplitude waves occur during late fall and early winter when the upper tropospheric winds directly overhead are fastest and the static stability of the lower troposphere is greatest. Mean wave amplitudes correlate highly with the product of the mean maximum wind speed and the mean low level stratification directly aloft. A distinct diurnal variation of wave amplitudes with the largest waves occurring in the pre-dawn hours is also observed as a result of the increased static stability then. The majority of waves are generated by shear instability; however, a number of waves are generated by distant sources such as nuclear detonations or large thunderstorms. The waves with distant sources can be distinguished on the basis of their generally much higher coherency across the grid and velocities that depart markedly from the wind velocity at any point in the sounding.

Seismicity of the Earth 1900-2010 eastern margin of the Australia plate

USGS Publications Warehouse

Benz, Harley M.; Herman, Matthew; Tarr, Arthur C.; Hayes, Gavin P.; Furlong, Kevin P.; Villaseñor, Antonio; Dart, Richard L.; Rhea, Susan

2011-01-01

The eastern margin of the Australia plate is one of the most seismically active areas of the world due to high rates of convergence between the Australia and Pacific plates. In the region of New Zealand, the 3,000 km long Australia-Pacific plate boundary extends from south of Macquarie Island to the southern Kermadec Island chain. It includes an oceanic transform (the Macquarie Ridge), two oppositely verging subduction zones (Puysegur and Hikurangi), and a transpressive continental transform, the Alpine Fault through South Island, New Zealand. Since 1900, there have been 15 M7.5+ earthquakes recorded near New Zealand. Nine of these, and the four largest, occurred along or near the Macquarie Ridge, including the 1989 M8.2 event on the ridge itself, and the 2004 M8.1 event 200 km to the west of the plate boundary, reflecting intraplate deformation. The largest recorded earthquake in New Zealand itself was the 1931 M7.8 Hawke's Bay earthquake, which killed 256 people. The last M7.5+ earthquake along the Alpine Fault was 170 years ago; studies of the faults' strain accumulation suggest that similar events are likely to occur again.

Self-bending of optical waveguides in a dry photosensitive medium

NASA Astrophysics Data System (ADS)

Malallah, Ra'ed; Wan, Min; Muniraj, Inbarasan; Cassidy, Derek; Sheridan, John T.

2018-03-01

Optical waveguide trajectories formed in an AA/PVA a photopolymer material photosensitive at 532 nm are examined. The transmission of light by this materials is discussed. The bending and arching of the waveguides which occur are investigated. The prediction of our model are shown to agree with the observed of trajectories. The largest index changes taking place at any time during the exposure, i.e. during SWW formation are found at the positions where the largest light intensity is present. Typically, such as maxima exist close to the input face at the location of the Primary Eye or at the location of the Secondary Eyes deeper with in the material. All photosensitive materials have a maximum saturation value of refractive index change that it is possible to induce, which is also discussed.

Transition year labeling error characterization study. [Kansas, Minnesota, Montana, North Dakota, South Dakota, and Oklahoma

NASA Technical Reports Server (NTRS)

Clinton, N. J. (Principal Investigator)

1980-01-01

Labeling errors made in the large area crop inventory experiment transition year estimates by Earth Observation Division image analysts are identified and quantified. The analysis was made from a subset of blind sites in six U.S. Great Plains states (Oklahoma, Kansas, Montana, Minnesota, North and South Dakota). The image interpretation basically was well done, resulting in a total omission error rate of 24 percent and a commission error rate of 4 percent. The largest amount of error was caused by factors beyond the control of the analysts who were following the interpretation procedures. The odd signatures, the largest error cause group, occurred mostly in areas of moisture abnormality. Multicrop labeling was tabulated showing the distribution of labeling for all crops.

Ultraviolet photochemistry of cyanoacetylene: Application to Titan. [Abstract only

NASA Technical Reports Server (NTRS)

Clarke, D. W.; Ferris, J. P.

1994-01-01

Cyanoacetylene is believed to have had a central role in the formation of the pyrimidines essential for RNA synthesis leading to the origin of life on Earth. Cyanoacetylene has also been detected on Titan, Saturn's largest moon, and the only moon in the solar system that possesses a dense atmosphere. It is generally accepted that photochemistry plays a major role in the formation of the complex organic molecules and aerosols found in Titan's atmosphere. Because of its long wavelength absorption and low dissociation threshold it is expected that cyanoacetylene is an important part of these photochemical processes. Since cyanoacetylene would also have been subject to ultraviolet light in the atmosphere of early Earth, an investigation of cyanoacetylene photochemistry on Titan might lead to a better understanding of both the photochemical reactions occurring on primitive earth and the processes of chemical evolution as they occur in planetary atmospheres. The effects of irradiation wavelength, mixing with Titan's atmospheric gases, reducing the temperature and lowering cyanoacetylene partial pressures on product formation and polymer composition have been determined with the ultimate goal of understanding the chemical transformations taking place in Titan's atmosphere.

On the structure of cellular solutions in Rayleigh-Benard-Marangoni flows in small-aspect-ratio containers

NASA Technical Reports Server (NTRS)

Dijkstra, Henk A.

1992-01-01

Multiple steady flow patterns occur in surface-tension/buoyancy-driven convection in a liquid layer heated from below (Rayleigh-Benard-Marangoni flows). Techniques of numerical bifurcation theory are used to study the multiplicity and stability of two-dimensional steady flow patterns (rolls) in rectangular small-aspect-ratio containers as the aspect ratio is varied. For pure Marangoni flows at moderate Biot and Prandtl number, the transitions occurring when paths of codimension 1 singularities intersect determine to a large extent the multiplicity of stable patterns. These transitions also lead, for example, to Hopf bifurcations and stable periodic flows for a small range in aspect ratio. The influence of the type of lateral walls on the multiplicity of steady states is considered. 'No-slip' lateral walls lead to hysteresis effects and typically restrict the number of stable flow patterns (with respect to 'slippery' sidewalls) through the occurrence of saddle node bifurcations. In this way 'no-slip' sidewalls induce a selection of certain patterns, which typically have the largest Nusselt number, through secondary bifurcation.

Embryotoxicity of benzalkonium chloride in vaginally treated rats.

PubMed

Buttar, H S

1985-12-01

The effects of the spermicide benzalkonium chloride (BKC) were studied on the conceptus of rat. Single doses (0, 25, 50, 100 or 200 mg kg-1) of aqueous solutions of BKC were administered intravaginally (1 ml kg-1) on gestational day 1. The vulval metallic clips, used to prevent leakage of the solution, were removed 24 h post-treatment. Fetuses were obtained and examined for malformations on day 21 of gestation. slight to copious amounts of vaginal discharge and vaginitis were noticed in rats treated with the two largest doses of BKC. A dose-related increase in resorptions and fetal death, reduction in litter size and weight were observed in BKC-treated dams. The conceptus loss seemed to occur both before and after implantation. BKC did not cause any discernible visceral malformations, although minor sternal defects occurred in fetuses exposed to 100 and 200 mg kg-1 of the spermicide. These results suggest that single vaginal application of BKC is embryo- and fetocidal in the rat at a dose about 143 times higher than that recommended for controlling conception in women.

Landslides triggered by the Minxian-Zhangxian, China, Mw 5.9 earthquake of 22 July 2013

NASA Astrophysics Data System (ADS)

Xu, Chong; Xu, Xiwei; Shyu, J. Bruce H.

2014-05-01

On July 22, 2013, an earthquake of Ms 6.6 occurred at the junction area of Minxian and Zhangxian counties, Gansu Province, China. This earthquake triggered many landslides of various types, dominated by small-scale soil falls, slides, and topples on loess scarps. There were also some deep-seated landslides, large-scale soil avalanches, and fissure-developing slopes. In this paper, an inventory of landslides triggered by this event is prepared based on field investigations and visual interpretation of high-resolution satellite images. The spatial distribution of the landslides is then analyzed. The inventory indicates that at least 2,330 landslides were triggered by the earthquake. A correlation statistics of the landslides with topographic, geologic, and earthquake factors is performed based on the GIS platform. The results show that the largest number of landslides and the highest landslide density are at 2,400m-2,600m of absolute elevation, and 200m-300m of relative elevation, respectively. The landslide density does not always increase with slope gradient as previously suggested. The slopes most prone to landslides are in S, SW, W, and NW directions. Concave slopes register higher landslide density and larger number of landslides than convex slopes. The largest number of landslides occurs on topographic position with middle slopes, whereas the highest landslide density corresponds to valleys and lower slopes. The underlying bedrocks consisting of conglomerate and sandstone of Lower Paleogene (Eb) register both the largest number of landslides and the highest landslide density value. There is no clear relationship between PGA and the co-seismic landslides. Correlations of landslide number and landslide density with perpendicular- and along-strike distance from the epicenter show an obvious spatial intensifying character of the co-seismic landslides. The spatial pattern of the co-seismic landslides is strongly controlled by a branch of the Lintan-Dangchang fault, which indicates the effect of seismogenic fault on co-seismic landslides. In addition, the landslide limit area related to the earthquake is compared to the relationship of "landslide limit area vs. earthquake magnitude" constructed based on earthquakes worldwide, and it is shown that the limit area of landslides triggered by the Minxian-Zhangxian earthquake is larger than that of almost all other events with similar magnitudes. This research was supported by the National Science Foundation of China (41202235).

More tornadoes in the most extreme U.S. tornado outbreaks

NASA Astrophysics Data System (ADS)

Tippett, Michael K.; Lepore, Chiara; Cohen, Joel E.

2016-12-01

Tornadoes and severe thunderstorms kill people and damage property every year. Estimated U.S. insured losses due to severe thunderstorms in the first half of 2016 were $8.5 billion (US). The largest U.S. effects of tornadoes result from tornado outbreaks, which are sequences of tornadoes that occur in close succession. Here, using extreme value analysis, we find that the frequency of U.S. outbreaks with many tornadoes is increasing and that it is increasing faster for more extreme outbreaks. We model this behavior by extreme value distributions with parameters that are linear functions of time or of some indicators of multidecadal climatic variability. Extreme meteorological environments associated with severe thunderstorms show consistent upward trends, but the trends do not resemble those currently expected to result from global warming.

Impact of medical loss regulation on the financial performance of health insurers.

PubMed

McCue, Michael; Hall, Mark; Liu, Xinliang

2013-09-01

The Affordable Care Act's regulation of medical loss ratios requires health insurers to use at least 80-85 percent of the premiums they collect for direct medical expenses (care delivery) or for efforts to improve the quality of care. To gauge this rule's effect on insurers' financial performance, we measured changes between 2010 and 2011 in key financial ratios reflecting insurers' operating profits, administrative costs, and medical claims. We found that the largest changes occurred in the individual market, where for-profit insurers reduced their median administrative cost ratio and operating margin by more than two percentage points each, resulting in a seven-percentage-point increase in their median medical loss ratio. Financial ratios changed much less for insurers in the small- and large-group markets.

Stress Interactions Between the 1976 Magnitude 7.8 Tangshan Earthquake and Adjacent Fault Systems in Northern China

NASA Astrophysics Data System (ADS)

Zhang, Z.; Lin, J.; Chen, Y. J.

2004-12-01

The 28 July 1976 ML = 7.8 Tangshan earthquake struck a highly populated metropolitan center in northern China and was one of the most devastating earthquakes in modern history. Its occurrence has significantly changed the Coulomb stresses on a complex network of strike-slip, normal, and thrust faults in the region, potentially heightened the odds of future earthquakes on some of these fault segments. We have conducted a detailed analysis of the 3D stress effects of the Tangshan earthquake on its neighboring faults, the relationship between stress transfer and aftershock locations, and the implications for future seismic hazard in the region. Available seismic and geodetic data, although limited, indicate that the Tangshan main shock sequence is composed of complex rupture on 2-3 fault segments. The dominant rupture mode is right-lateral strike-slip on two adjoining sub-segments that strike N5¡aE and N35¡aE, respectively. We calculated that the Tangshan main shock sequence has increased the Coulomb failure stress by more than 1 bar in the vicinity of the Lunanxian district to the east, where the largest aftershock (ML = 7.1) occurred 15 hours after the Tangshan main event. The second largest aftershock (ML = 6.8) occurred on the Ninghe fault to the southwest of the main rupture, in a transitional region between the calculated Coulomb stress increase and decrease. The majority of the ML > 5.0 aftershocks also occurred in areas of calculated Coulomb stress increase. Our analyses further indicate that the Coulomb stress on portions of other fault segments, including the Leting and Lulong fault to the east and Yejito fault to the north, may also have been increased. Thus it is critical to obtain estimates of earthquake repeat times on these and other tectonic faults and to acquire continuous GPS and space geodetic measurements. Investigation of stress interaction and earthquake triggering in northern China is not only highly societal relevant but also important for advancing our understanding of the fundamental characteristics of earthquakes in regions of diffuse continental deformation.

Groundwater-flow model of the Ozark Plateaus aquifer system, northwestern Arkansas, southeastern Kansas, southwestern Missouri, and northeastern Oklahoma

USGS Publications Warehouse

Czarnecki, John B.; Gillip, Jonathan A.; Jones, Perry M.; Yeatts, Daniel S.

2009-01-01

To assess the effect that increased water use is having on the long-term availability of groundwater within the Ozark Plateaus aquifer system, a groundwater-flow model was developed using MODFLOW 2000 for a model area covering 7,340 square miles for parts of Arkansas, Kansas, Missouri, and Oklahoma. Vertically the model is divided into five units. From top to bottom these units of variable thickness are: the Western Interior Plains confining unit, the Springfield Plateau aquifer, the Ozark confining unit, the Ozark aquifer, and the St. Francois confining unit. Large mined zones contained within the Springfield Plateau aquifer are represented in the model as extensive voids with orders-of-magnitude larger hydraulic conductivity than the adjacent nonmined zones. Water-use data were compiled for the period 1960 to 2006, with the most complete data sets available for the period 1985 to 2006. In 2006, total water use from the Ozark aquifer for Missouri was 87 percent (8,531,520 cubic feet per day) of the total pumped from the Ozark aquifer, with Kansas at 7 percent (727,452 cubic feet per day), and Oklahoma at 6 percent (551,408 cubic feet per day); water use for Arkansas within the model area was minor. Water use in the model from the Springfield Plateau aquifer in 2005 was specified from reported and estimated values as 569,047 cubic feet per day. Calibration of the model was made against average water-level altitudes in the Ozark aquifer for the period 1980 to 1989 and against waterlevel altitudes obtained in 2006 for the Springfield Plateau and Ozark aquifers. Error in simulating water-level altitudes was largest where water-level altitude gradients were largest, particularly near large cones of depression. Groundwater flow within the model area occurs generally from the highlands of the Springfield Plateau in southwestern Missouri toward the west, with localized flow occurring towards rivers and pumping centers including the five largest pumping centers near Joplin, Missouri; Carthage, Missouri; Noel, Missouri; Pittsburg, Kansas; and Miami, Oklahoma.Hypothetical scenarios involving various increases in groundwater-pumping rates were analyzed with the calibrated groundwater-flow model to assess changes in the flow system from 2007 to the year 2057. Pumping rates were increased between 0 and 4 percent per year starting with the 2006 rates for all wells in the model. Sustained pumping at 2006 rates was feasible at the five pumping centers until 2057; however, increases in pumping resulted in dewatering the aquifer and thus pumpage increases were not sustainable in Carthage and Noel for the 1 percent per year pumpage increase and greater hypothetical scenarios, and in Joplin and Miami for the 4 percent per year pumpage increase hypothetical scenarios.Zone-budget analyses were performed to assess the groundwater flow into and out of three zones specified within the Ozark-aquifer layer of the model. The three zones represented the model part of the Ozark aquifer in Kansas (zone 1), Oklahoma (zone 2), and Missouri and Arkansas (zone 3). Groundwater pumping causes substantial reductions in water in storage and induces flow through the Ozark confining unit for all hypothetical scenarios evaluated. Net simulated flow in 2057 from Kansas (zone 1) to Missouri (zone 3) ranges from 74,044 cubic feet per day for 2006 pumping rates (hypothetical scenario 1) to 625,319 cubic feet per day for a 4 percent increase in pumping per year (hypothetical scenario 5). Pumping from wells completed in the Ozark aquifer is the largest component of flow out of zone 3 in Missouri and Arkansas, and varies between 88 to 91 percent of the total flow out of zone 3 for all of the hypothetical scenarios. The largest component of flow into Oklahoma (zone 2) comes from the overlying Ozark confining unit, which is consistently about 45 percent of the total. Flow from the release of water in storage, from general-head boundaries, and from zones 1 and 3 is considerably smaller values that range from 3 to 22 percent of the total flow into zone 2. The largest flow out of the Oklahoma part of the model occurs from pumping from wells and ranges from 52 to 69 percent of the total.

Effects of economic crises on population health outcomes in Latin America, 1981–2010: an ecological study

PubMed Central

Williams, Callum; Gilbert, Barnabas James; Zeltner, Thomas; Watkins, Johnathan; Atun, Rifat; Maruthappu, Mahiben

2016-01-01

Objectives The relative health effects of changes in unemployment, inflation and gross domestic product (GDP) per capita on population health have not been assessed. We aimed to determine the effect of changes in these economic measures on mortality metrics across Latin America. Design Ecological study. Setting Latin America (21 countries), 1981–2010. Outcome measures Uses multivariate regression analysis to assess the effects of changes in unemployment, inflation and GDP per capita on 5 mortality indicators across 21 countries in Latin America, 1981–2010. Country-specific differences in healthcare infrastructure, population structure and population size were controlled for. Results Between 1981 and 2010, a 1% rise in unemployment was associated with statistically significant deteriorations (p<0.05) in 5 population health outcomes, with largest deteriorations in 1–5 years of age and male adult mortality rates (1.14 and 0.53 rises per 1000 deaths respectively). A 1% rise in inflation rate was associated with significant deteriorations (p<0.05) in 4 population health outcomes, with the largest deterioration in male adult mortality rate (0.0033 rise per 1000 deaths). Lag analysis showed that 5 years after rises in unemployment and inflation, significant deteriorations (p<0.05) occurred in 3 and 5 mortality metrics, respectively. A 1% rise in GDP per capita was associated with no significant deteriorations in population health outcomes either in the short or long term. β coefficient comparisons indicated that the effect of unemployment increases was substantially greater than that of changes in GDP per capita or inflation. Conclusions Rises in unemployment and inflation are associated with long-lasting deteriorations in several population health outcomes. Unemployment exerted much larger effects on health than inflation. In contrast, changes in GDP per capita had almost no association with the explored health outcomes. Contrary to neoclassical development economics, policymakers should prioritise amelioration of unemployment if population health outcomes are to be optimised. PMID:26739715

Effects of a temperature-dependent rheology on large scale continental extension

NASA Technical Reports Server (NTRS)

Sonder, Leslie J.; England, Philip C.

1988-01-01

The effects of a temperature-dependent rheology on large-scale continental extension are investigated using a thin viscous sheet model. A vertically-averaged rheology is used that is consistent with laboratory experiments on power-law creep of olivine and that depends exponentially on temperature. Results of the calculations depend principally on two parameters: the Peclet number, which describes the relative rates of advection and diffusion of heat, and a dimensionless activation energy, which controls the temperature dependence of the rheology. At short times following the beginning of extension, deformation occurs with negligible change in temperature, so that only small changes in lithospheric strength occur due to attenuation of the lithosphere. However, after a certain critical time interval, thermal diffusion lowers temperatures in the lithosphere, strongly increasing lithospheric strength and slowing the rate of extension. This critical time depends principally on the Peclet number and is short compared with the thermal time constant of the lithosphere. The strength changes cause the locus of high extensional strain rates to shift with time from regions of high strain to regions of low strain. Results of the calculations are compared with observations from the Aegean, where maximum extensional strains are found in the south, near Crete, but maximum present-day strain rates are largest about 300 km further north.

Redox reactions and weak buffering capacity lead to acidification in the Chesapeake Bay.

PubMed

Cai, Wei-Jun; Huang, Wei-Jen; Luther, George W; Pierrot, Denis; Li, Ming; Testa, Jeremy; Xue, Ming; Joesoef, Andrew; Mann, Roger; Brodeur, Jean; Xu, Yuan-Yuan; Chen, Baoshan; Hussain, Najid; Waldbusser, George G; Cornwell, Jeffrey; Kemp, W Michael

2017-08-28

The combined effects of anthropogenic and biological CO 2 inputs may lead to more rapid acidification in coastal waters compared to the open ocean. It is less clear, however, how redox reactions would contribute to acidification. Here we report estuarine acidification dynamics based on oxygen, hydrogen sulfide (H 2 S), pH, dissolved inorganic carbon and total alkalinity data from the Chesapeake Bay, where anthropogenic nutrient inputs have led to eutrophication, hypoxia and anoxia, and low pH. We show that a pH minimum occurs in mid-depths where acids are generated as a result of H 2 S oxidation in waters mixed upward from the anoxic depths. Our analyses also suggest a large synergistic effect from river-ocean mixing, global and local atmospheric CO 2 uptake, and CO 2 and acid production from respiration and other redox reactions. Together they lead to a poor acid buffering capacity, severe acidification and increased carbonate mineral dissolution in the USA's largest estuary.The potential contribution of redox reactions to acidification in coastal waters is unclear. Here, using measurements from the Chesapeake Bay, the authors show that pH minimum occurs at mid-depths where acids are produced via hydrogen sulfide oxidation in waters mixed upward from anoxic depths.

Incidence of first ever stroke during Hajj ceremony

PubMed Central

2013-01-01

Background The Hajj Ceremony, the largest annual gathering in the world, is the most important life event for any Muslim. This study was designed to evaluate the incidence of stroke among Iranian pilgrims during the Hajj ceremony. Methods We ascertained all cases of stroke occurring in a population of 92,974 Iranian pilgrims between November 27, 2007 and January 12, 2008. Incidence and risk factors of the first ever stroke in Hajj pilgrims were compared, within the same time frame, to those of the Mashhad residents, the second largest city in Iran. Data for the latter group were extracted from the Mashhad Stroke Incidence Study (MSIS) database. Results During the study period, 17 first-ever strokes occurred in the Hajj pilgrims and 40 first-ever stroke strokes occurred in the MSIS group. Overall, the adjusted incidence rate of first ever stroke in the Hajj cohort was lower than that of the MSIS population (9 vs. 16 per 100,000). For age- and gender-specific subgroups, the Hajj stroke crude rates were in general similar to or lower than the general population of Mashhad, Iran, with the exception of women aged 35 to 44 years and aged >75 years who were at greater risk of having first-ever stroke than the non-pilgrims of the same age. Conclusion The first ever stroke rate among Iranian Hajj pilgrims was lower than that of the general population in Mashhad, Iran, except for females 35–44 or more than 75 years old. The number of events occurring during the Hajj suggests that Islamic countries should consider designing preventive and screening programs for pilgrims. PMID:24308305

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rowland, Joel C; Manga, Michael

The origin of increased stream flow and spring discharge following earthquakes have been the subject of controversy, in large part because there are many models to explain observations and few measurements suitable for distinguishing between hypotheses. On October 30, 2007 a magnitude 5.5 earthquake occurred near the Alum Rock springs, California, USA. Within a day we documented a several-fold increase in discharge. Over the following year, we have monitored a gradual return towards pre-earthquake properties, but for the largest springs there appears to be a permanent increase in the steady discharge at all the springs. The Alum Rock springs dischargemore » waters that represent a mixture between modern ('shallow') meteoric water and old ('deep') connate waters expelled by regional transpression. After the earthquake, the increased discharge at the largest springs was accompanied by a small decrease in the fraction of connate water in the spring discharge. Combined with the rapid response, this implies that the increased discharge has a shallow origin. Increased discharge at these springs occurs for earthquakes that cause static volumetric expansion and those that cause contraction, supporting models in which dynamic strains are responsible for the subsurface changes that cause flow to increase. We show that models in which the permeability of the fracture system feeding the springs increases after the earthquake are in general consistent with the changes in discharge. The response of these springs to another earthquake will provide critical constraints on the changes that occur in the subsurface.« less

Impacts of a massive release of methane and hydrogen sulfide on oxygen and ozone during the late Permian mass extinction

NASA Astrophysics Data System (ADS)

Kaiho, Kunio; Koga, Seizi

2013-08-01

The largest mass extinction of animals and plants in both the ocean and on land occurred in the late Permian (252 Ma), largely coinciding with the largest flood basalt volcanism event in Siberia and an oceanic anoxic/euxinic event. We investigated the impacts of a massive release of methane (CH4) from the Siberian igneous province and the ocean and/or hydrogen sulfide (H2S) from the euxinic ocean on oxygen and ozone using photochemical model calculations. Our calculations indicated that an approximate of 14% decrease in atmospheric O2 levels would have occurred in the case of a large combined CH4 and H2S flux to the atmosphere, whereas an approximate of 8 to 10% decrease would have occurred from the CH4 flux and oxidation of all H2S in the ocean. The slight decrease in atmospheric O2 levels may have contributed to the extinction event. We demonstrate for the first time that a massive release of CH4 from the Siberian igneous province and a coincident massive release of CH4 and H2S did not cause ozone collapse. A collapse of stratospheric ozone leading to an increase in UV is not supported by the maximum model input levels for CH4 and H2S. These conclusions on O2 and O3 are correspondent to every H2S release percentages from the ocean to the atmosphere.

Short and Long-Term Soil Moisture Effects of Liana Removal in a Seasonally Moist Tropical Forest

PubMed Central

Reid, Joseph Pignatello; Schnitzer, Stefan A.; Powers, Jennifer S.

2015-01-01

Lianas (woody vines) are particularly abundant in tropical forests, and their abundance is increasing in the neotropics. Lianas can compete intensely with trees for above- and belowground resources, including water. As tropical forests experience longer and more intense dry seasons, competition for water is likely to intensify. However, we lack an understanding of how liana abundance affects soil moisture and hence competition with trees for water in tropical forests. To address this critical knowledge gap, we conducted a large-scale liana removal experiment in a seasonal tropical moist forest in central Panama. We monitored shallow and deep soil moisture over the course of three years to assess the effects of lianas in eight 0.64 ha removal plots and eight control plots. Liana removal caused short-term effects in surface soils. Surface soils (10 cm depth) in removal plots dried more slowly during dry periods and accumulated water more slowly after rainfall events. These effects disappeared within four months of the removal treatment. In deeper soils (40 cm depth), liana removal resulted in a multi-year trend towards 5–25% higher soil moisture during the dry seasons with the largest significant effects occurring in the dry season of the third year following treatment. Liana removal did not affect surface soil temperature. Multiple and mutually occurring mechanisms may be responsible for the effects of liana removal on soil moisture, including competition with trees, and altered microclimate, and soil structure. These results indicate that lianas influence hydrologic processes, which may affect tree community dynamics and forest carbon cycling. PMID:26545205

Effect of fresh orange juice intake on physiological characteristics in healthy volunteers.

PubMed

Asgary, Sedigheh; Keshvari, Mahtab; Afshani, Mohammad Reza; Amiri, Masoud; Laher, Ismail; Javanmard, Shaghayegh Haghjooy

2014-01-01

Background. Impaired endothelial function is a predictor of cardiovascular events. Orange juice (OJ) is rich in dietary flavonoids and could inhibit oxidative stress and inflammatory responses. We examined the effects of commercial (COJ) and fresh orange juice (FOJ) on endothelial function and physiological characteristics in healthy humans. Materials and Methods. Twenty-two healthy volunteers years were enrolled in a single blind randomized crossover controlled trial. The two groups consumed either COJ for the first 4 weeks and then FOJ (CFOJ, 4 weeks), or FOJ for the first 4 weeks and then COJ (FCOJ, 4 weeks). We assessed endothelial function by measuring flow-mediated dilation, serum concentrations of lipids, apolipoproteins A and B (apo A-1 and apo B), and inflammatory markers such as vascular endothelial adhesion molecule 1 (VCAM-1), E-selectin, high-sensitivity C-reactive protein (hs-CRP), and interleukin-6. Results. Consumption of both juices decreased VCAM, hs-CRP, and E-selectin but increased apo A-1. A decline in LDL occurred in the FOJ group. There were no differences between the characteristics of two groups, with the exception of apo A-1 levels that were increased with both forms of OJ. The largest variations occurred with hs-CRP, VCAM in both groups. Conclusion. Consumption of COJ and FOJ produced beneficial effects on the physiological characteristics of healthy volunteers. Although these results could encourage the consumption of OJ, intervention studies are needed to determine the long-term effects of these types of OJ on metabolic and cardiovascular endpoints.

Satisfaction with nursing education, job satisfaction, and work intentions of new graduate nurses.

PubMed

Kenny, Patricia; Reeve, Rebecca; Hall, Jane

2016-01-01

In the context of predictions of future shortages of nurses, retaining new graduate nurses in the nursing workforce is essential to ensure sufficient nurses in the future. This paper investigates the links between satisfaction with nursing education and job satisfaction, and job dissatisfaction and intentions to leave a nursing job. It uses survey data from a cohort study of nursing students recruited through two Australian universities and followed after graduation and workforce entry. Structural equation modeling (SEM) was used to simultaneously estimate the impact of educational satisfaction (work preparation component) on job satisfaction and the impact of job satisfaction on the expectation of leaving the current job. Two job satisfaction sub-scales were identified: 1) work environment satisfaction and 2) work hours and wages satisfaction. Work preparation satisfaction was significantly and positively associated with both job satisfaction scales but only work environment satisfaction was significantly associated with the expectation to stay in the job; a one standard deviation increase in work environment satisfaction was associated with a 13.5 percentage point reduction in the probability of expecting to leave. The estimated effect of satisfaction with education on expecting to leave, occurring indirectly through job satisfaction, was small (reducing the probability by less than 3 percentage points for a 1 point increase in work preparation satisfaction). Participating in a graduate transition program had the largest effect, reducing the probability of expecting to leave by 26 percentage points, on average. The study results suggest policies which focus on improving satisfaction with the work environment would be more effective at retaining nurses early in their career than improvements to conditions such as work hours and wages. Investment in new graduate transition programs would potentially have the largest impact on retention. Copyright © 2015 Elsevier Ltd. All rights reserved.

Rejuvenating the Largest Treatment Wetland in Florida: Tracer Moment and Model Analysis of Wetland Hydraulic Performance

NASA Astrophysics Data System (ADS)

White, J. R.; Wang, H.; Jawitz, J. W.; Sees, M. D.

2004-12-01

The Orlando Easterly Wetland (OEW), the largest municipal treatment wetland in Florida, began operation in 1987 mainly for reducing nutrient loads in tertiary treated domestic wastewater produced by the city of Orlando. After more than ten years of operation, a decrease in total P removal effectiveness has occurred since 1999, even though the effluent concentration of the wetland has remained below the permitted limit of 0.2 mg/L,. Hydraulic inefficiency in the wetland, especially in the front-end cells of the north flow train, was identified as a primary cause of the reduced treatment effectiveness. In order to improve the hydraulic performance of the OEW and maintain its efficient phosphorus treatment, a rejuvenation program (including muck removal followed by re-vegetation) was initiated on the front-end cells of the north flow train in 2002. The effectiveness of this activity for the improvement of hydraulic performance was evaluated with a tracer test and subsequent moment and model analyses for the tracer resident time distribution (RTDs). Results were compared to similar tracer tests conducted prior to rejuvenation activities. The models included one-path tank-in-series (TIS), two-path TIS, one-dimensional transport with inflow and storage (OTIS), plug flow with dispersion (PFD), and plug flow with fractional dispersion (PFFD). The hydraulic performance was characterized by both wetland hydraulic efficiency and the spreading of tracers. The results demonstrated that the rejuvenation considerably improved the hydraulic performance in the restored area. Also presented is a comparison of the wetland response between both bromide and lithium tracers, and the determination of the complete moments of residence time distributions (RTD) in cell-network wetlands.

A statistical approach to determining energetic outer radiation belt electron precipitation fluxes

NASA Astrophysics Data System (ADS)

Simon Wedlund, Mea; Clilverd, Mark A.; Rodger, Craig J.; Cresswell-Moorcock, Kathy; Cobbett, Neil; Breen, Paul; Danskin, Donald; Spanswick, Emma; Rodriguez, Juan V.

2014-05-01

Subionospheric radio wave data from an Antarctic-Arctic Radiation-Belt (Dynamic) Deposition VLF Atmospheric Research Konsortia (AARDDVARK) receiver located in Churchill, Canada, is analyzed to determine the characteristics of electron precipitation into the atmosphere over the range 3 < L < 7. The study advances previous work by combining signals from two U.S. transmitters from 20 July to 20 August 2010, allowing error estimates of derived electron precipitation fluxes to be calculated, including the application of time-varying electron energy spectral gradients. Electron precipitation observations from the NOAA POES satellites and a ground-based riometer provide intercomparison and context for the AARDDVARK measurements. AARDDVARK radiowave propagation data showed responses suggesting energetic electron precipitation from the outer radiation belt starting 27 July 2010 and lasting ~20 days. The uncertainty in >30 keV precipitation flux determined by the AARDDVARK technique was found to be ±10%. Peak >30 keV precipitation fluxes of AARDDVARK-derived precipitation flux during the main and recovery phase of the largest geomagnetic storm, which started on 4 August 2010, were >105 el cm-2 s-1 sr-1. The largest fluxes observed by AARDDVARK occurred on the dayside and were delayed by several days from the start of the geomagnetic disturbance. During the main phase of the disturbances, nightside fluxes were dominant. Significant differences in flux estimates between POES, AARDDVARK, and the riometer were found after the main phase of the largest disturbance, with evidence provided to suggest that >700 keV electron precipitation was occurring. Currently the presence of such relativistic electron precipitation introduces some uncertainty in the analysis of AARDDVARK data, given the assumption of a power law electron precipitation spectrum.

The 2016 Mihoub (north-central Algeria) earthquake sequence: Seismological and tectonic aspects

NASA Astrophysics Data System (ADS)

Khelif, M. F.; Yelles-Chaouche, A.; Benaissa, Z.; Semmane, F.; Beldjoudi, H.; Haned, A.; Issaadi, A.; Chami, A.; Chimouni, R.; Harbi, A.; Maouche, S.; Dabbouz, G.; Aidi, C.; Kherroubi, A.

2018-06-01

On 28 May 2016 at 23:54 (UTC), an Mw5.4 earthquake occurred in Mihoub village, Algeria, 60 km southeast of Algiers. This earthquake was the largest event in a sequence recorded from 10 April to 15 July 2016. In addition to the permanent national network, a temporary network was installed in the epicentral region after this shock. Recorded event locations allow us to give a general overview of the sequence and reveal the existence of two main fault segments. The first segment, on which the first event in the sequence was located, is near-vertical and trends E-W. The second fault plane, on which the largest event of the sequence was located, dips to the southeast and strikes NE-SW. A total of 46 well-constrained focal mechanisms were calculated. The events located on the E-W-striking fault segment show mainly right-lateral strike-slip (strike N70°E, dip 77° to the SSE, rake 150°). The events located on the NE-SW-striking segment show mainly reverse faulting (strike N60°E, dip 70° to the SE, rake 130°). We calculated the static stress change caused by the first event (Md4.9) of the sequence; the result shows that the fault plane of the largest event in the sequence (Mw5.4) and most of the aftershocks occurred within an area of increased Coulomb stress. Moreover, using the focal mechanisms calculated in this work, we estimated the orientations of the main axes of the local stress tensor ellipsoid. The results confirm previous findings that the general stress field in this area shows orientations aligned NNW-SSE to NW-SE. The 2016 Mihoub earthquake sequence study thus improves our understanding of seismic hazard in north-central Algeria.

Rhodolith Beds Are Major CaCO3 Bio-Factories in the Tropical South West Atlantic

PubMed Central

Amado-Filho, Gilberto M.; Moura, Rodrigo L.; Bastos, Alex C.; Salgado, Leonardo T.; Sumida, Paulo Y.; Guth, Arthur Z.; Francini-Filho, Ronaldo B.; Pereira-Filho, Guilherme H.; Abrantes, Douglas P.; Brasileiro, Poliana S.; Bahia, Ricardo G.; Leal, Rachel N.; Kaufman, Les; Kleypas, Joanie A.; Farina, Marcos; Thompson, Fabiano L.

2012-01-01

Rhodoliths are nodules of non-geniculate coralline algae that occur in shallow waters (<150 m depth) subjected to episodic disturbance. Rhodolith beds stand with kelp beds, seagrass meadows, and coralline algal reefs as one of the world's four largest macrophyte-dominated benthic communities. Geographic distribution of rhodolith beds is discontinuous, with large concentrations off Japan, Australia and the Gulf of California, as well as in the Mediterranean, North Atlantic, eastern Caribbean and Brazil. Although there are major gaps in terms of seabed habitat mapping, the largest rhodolith beds are purported to occur off Brazil, where these communities are recorded across a wide latitudinal range (2°N - 27°S). To quantify their extent, we carried out an inter-reefal seabed habitat survey on the Abrolhos Shelf (16°50′ - 19°45′S) off eastern Brazil, and confirmed the most expansive and contiguous rhodolith bed in the world, covering about 20,900 km2. Distribution, extent, composition and structure of this bed were assessed with side scan sonar, remotely operated vehicles, and SCUBA. The mean rate of CaCO3 production was estimated from in situ growth assays at 1.07 kg m−2 yr−1, with a total production rate of 0.025 Gt yr−1, comparable to those of the world's largest biogenic CaCO3 deposits. These gigantic rhodolith beds, of areal extent equivalent to the Great Barrier Reef, Australia, are a critical, yet poorly understood component of the tropical South Atlantic Ocean. Based on the relatively high vulnerability of coralline algae to ocean acidification, these beds are likely to experience a profound restructuring in the coming decades. PMID:22536356

Toward a consistent model for strain accrual and release for the New Madrid Seismic Zone, central United States

USGS Publications Warehouse

Hough, S.E.; Page, M.

2011-01-01

At the heart of the conundrum of seismogenesis in the New Madrid Seismic Zone is the apparently substantial discrepancy between low strain rate and high recent seismic moment release. In this study we revisit the magnitudes of the four principal 1811–1812 earthquakes using intensity values determined from individual assessments from four experts. Using these values and the grid search method of Bakun and Wentworth (1997), we estimate magnitudes around 7.0 for all four events, values that are significantly lower than previously published magnitude estimates based on macroseismic intensities. We further show that the strain rate predicted from postglacial rebound is sufficient to produce a sequence with the moment release of one Mmax6.8 every 500 years, a rate that is much lower than previous estimates of late Holocene moment release. However, Mw6.8 is at the low end of the uncertainty range inferred from analysis of intensities for the largest 1811–1812 event. We show that Mw6.8 is also a reasonable value for the largest main shock given a plausible rupture scenario. One can also construct a range of consistent models that permit a somewhat higher Mmax, with a longer average recurrence rate. It is thus possible to reconcile predicted strain and seismic moment release rates with alternative models: one in which 1811–1812 sequences occur every 500 years, with the largest events being Mmax∼6.8, or one in which sequences occur, on average, less frequently, with Mmax of ∼7.0. Both models predict that the late Holocene rate of activity will continue for the next few to 10 thousand years.

An Elusive Policy Imperative: Data and Methodological Challenges When Using Growth in Student Achievement to Evaluate Teacher Education Programs' "Value-Added"

ERIC Educational Resources Information Center

Amrein-Beardsley, Audrey; Lawton, Kerry; Ronan, Katherine

2017-01-01

In this study researchers examined the effectiveness of one of the largest teacher education programs located within the largest research-intensive universities within the US. They did this using a value-added model as per current federal educational policy imperatives to assess the measurable effects of teacher education programs on their teacher…

Why is the electrocaloric effect so small in ferroelectrics?

NASA Astrophysics Data System (ADS)

Guzman-Verri, Gian G.; Littlewood, Peter B.

2015-03-01

Ferroelectrics are attractive candidate materials for environmentally friendly solid state refrigeration free of greenhouse gases. Their thermal response upon variations of external electric fields is largest in the vicinity of their phase transitions, which may occur near room temperature. The magnitude of the effect, however, is too small for useful cooling applications even when they are driven close to dielectric breakdown. Insight from microscopic theory is therefore needed to characterize materials and provide guiding principles to search for new ones with enhanced electrocaloric performance. Here, we present meaningful figures of merit derived from well-known microscopic models of ferroelectricity which provide insight into the relation between the strength of the effect and the characteristic interactions of ferroelectrics such as dipole forces. We find that the long range nature of these interactions results in a small effect. A strategy is proposed to make it larger by shortening the correlation lengths of fluctuations of polarization. Work at Argonne is supported by the U.S. Department of Energy, Office of Basic Energy Sciences under Contract No. DE-AC02-06CH11357.

Free-Energy Barrier of Filling a Spherical Cavity in the Presence of Line Tension: Implication to the Energy Barrier between the Cassie and Wenzel States on a Superhydrophobic Surface with Spherical Cavities.

PubMed

Iwamatsu, Masao

2016-09-20

The free-energy barrier of filling a spherical cavity having an inner wall of various wettabilities is studied. The morphology and free energy of a lens-shaped droplet are determined from the minimum of the free energy. The effect of line tension on the free energy is also studied. Then, the equilibrium contact angle of the droplet is determined from the generalized Young's equation. By increasing the droplet volume within the spherical cavity, the droplet morphology changes from spherical with an equilibrium contact angle of 180° to a lens with a convex meniscus, where the morphological complete drying transition occurs. By further increasing the droplet volume, the meniscus changes from convex to concave. Then, the lens-shaped droplet with concave meniscus spreads over the whole inner wall, resulting in an equilibrium contact angle of 0° to leave a spherical bubble, where the morphological complete wetting transition occurs. Finally, the whole cavity is filled with liquid. The free energy shows a barrier from complete drying to complete wetting as a function of droplet volume, which corresponds to the energy barrier between the Cassie and Wenzel states of the superhydrophobic surface with spherical cavities. The free-energy maximum occurs when the meniscus of the droplet becomes flat, and it is given by an analytic formula. The effect of line tension is expressed by the scaled line tension, and this effect is largest at the free-energy maximum. The positive line tension increases the free-energy maximum, which thus increases the stability of the Cassie superhydrophobic state, whereas the negative line tension destabilizes the superhydrophobic state.

Effect of bank protection measures, Stehekin River, Chelan County, Washington

USGS Publications Warehouse

Nelson, L.M.

1986-01-01

An investigation of the lower Stehekin River was conducted to study the effects on flood elevations and velocities from four bank protection and flood prevention measures that are being contemplated as a means of reducing erosional losses of river bank property. These measures are: bank armoring, armored revetment levees, spur dikes, and redevelopment of old cutoff channels. The banks at seven study sites could be armored without adverse effect on the flood velocities and elevations. The largest increases due to armoring--up to 1.6 ft/sec in velocity and 1 ft in elevation--occurred in the vicinity of sites 5, 6, and 7 where the gradient of the river channel is about 50 ft/mi and the velocities are high to begin with (about 6 to 13 ft/sec). The use of a levee in conjunction with armoring on the northeast bank from sites 5 to 7 would increase the velocities as much as 2.8 ft/sec and increase the elevation as much as 1 ft, but it would also provide some flood protection to the east bank, which is frequently inundated. Spur dikes were considered a practical alternative only at site 3, where reduced bank erosion may occur without aggravating flood inundation or erosion elsewhere. The rerouting of flood flow through an old cutoff channel near site 1 increased the velocity by 3.2 ft/sec and the elevation by 1 ft for the 100-year flood; however, it would move floodwater away from residential property where bank erosion is a problem. The few other old channels that shortcut river bends where much erosion occurs are apparently already part of the channel during floods. (Author 's abstract)

Numerical Study of Contaminant Effects on Combustion of Hydrogen, Ethane, and Methane in Air

NASA Technical Reports Server (NTRS)

Lai, H. T.; Thomas, S. R.

1995-01-01

A numerical study was performed to assess the effects of vitiated air on the chemical kinetics of hydrogen, ethane, and methane combustion with air. A series of calculations in static reacting systems was performed, where the initial temperature was specified and reactions occurred at constant pressure. Three different types of test flow contaminants were considered: NP, H2O, and a combustion of H2O and CO2. These contaminants are present in the test flows of facilities used for hypersonic propulsion testing. The results were computed using a detailed reaction mechanism and are presented in terms of ignition and reaction times. Calculations were made for a wide range of contaminant concentrations, temperatures and pressures. The results indicate a pronounced kinetic effect over a range of temperatures, especially with NO contamination and, to a lesser degree, with H2O contamination. In all cases studied, CO2 remained kinetically inert, but had a thermodynamic effect on results by acting as a third body. The largest effect is observed with combustion using hydrogen fuel, less effect is seen with combustion of ethane, and little effect of contaminants is shown with methane combustion.

Numerical study of contaminant effects on combustion of hydrogen, ethane, and methane in air

NASA Technical Reports Server (NTRS)

Lai, H. T.; Thomas, S. R.

1995-01-01

A numerical study was performed to assess the effects of vitiated air on the chemical kinetics of hydrogen, ethane, and methane combustion with air. A series of calculations in static reacting systems was performed, where the initial temperature was specified and reactions occurred at constant pressure. Three different types of test flow contaminants were considered: NO, H2O, and a combination of H2O and CO2. These contaminants are present in the test flows of facilities used for hypersonic propulsion testing. The results were computed using a detailed reaction mechanism and are presented in terms of ignition and reaction times. Calculations were made for a wide range of contaminant concentrations, temperatures and pressures. The results indicate a pronounced kinetic effect over a range of temperatures, especially with NO contamination and, to a lesser degree, with H2O contamination. In all cases studied, CO2 remained kinetically inert, but had a thermodynamically effect on results by acting as a third body. The largest effect is observed with combustion using hydrogen fuel, less effect is seen with combustion of ethane, and little effect of contaminants is shown with methane combustion.

Effects of paternal phenotype and environmental variability on age and size at maturity in a male dimorphic mite

NASA Astrophysics Data System (ADS)

Smallegange, Isabel M.

2011-04-01

Investigating how the environment affects age and size at maturity of individuals is crucial to understanding how changes in the environment affect population dynamics through the biology of a species. Paternal phenotype, maternal, and offspring environment may crucially influence these traits, but to my knowledge, their combined effects have not yet been tested. Here, I found that in bulb mites ( Rhizoglyphus robini), maternal nutrition, offspring nutrition, and paternal phenotype (males are fighters, able to kill other mites, or benign scramblers) interactively affected offspring age and size at maturity. The largest effect occurred when both maternal and offspring nutrition was poor: in that case offspring from fighter sires required a significantly longer development time than offspring from scrambler sires. Investigating parental effects on the relationship between age and size at maturity revealed no paternal effects, and only for females was its shape influenced by maternal nutrition. Overall, this reaction norm was nonlinear. These non-genetic intergenerational effects may play a complex, yet unexplored role in influencing population fluctuations—possibly explaining why results from field studies often do not match theoretical predictions on maternal effects on population dynamics.

Deep crustal earthquakes associated with continental rifts

NASA Astrophysics Data System (ADS)

Doser, Diane I.; Yarwood, Dennis R.

1994-01-01

Deep (> 20 km) crustal earthquakes have occurred within or along the margins of at least four continental rift zones. The largest of these deep crustal earthquakes ( M ⩾ 5.0) have strike-slip or oblique-slip mechanisms with T-axes oriented similarly to those associated with shallow normal faulting within the rift zones. The majority of deep crustal earthquakes occur along the rift margins in regions that have cooler, thicker crust. Several deep crustal events, however, occur in regions of high heat flow. These regions also appear to be regions of high strain, a factor that could account for the observed depths. We believe the deep crustal earthquakes represent either the relative motion of rift zones with respect to adjacent stable regions or the propagation of rifting into stable regions.

China’s Economic Conditions

DTIC Science & Technology

2008-11-20

occurred during the 1997-1998 Asian financial crisis when it offered financial assistance to Thailand and pledged not to devalue its currency even though...combination of large trade surpluses, foreign direct investment flows, and large-scale purchases of foreign currency have helped make China the world’s largest...Trade Organization (WTO) commitments and to change various economic policies deemed harmful to U.S. economic interests, such as its currency policy

Short-term response of methane fluxes and methanogen activity to water table and soil warming manipulations in an Alaskan peatland

Treesearch

M.R. Turetsky; C.C. Treat; M. Waldrop; J.M. Waddington; J.W. Harden; A.D. McGuire

2008-01-01

Growing season CH4 fluxes were monitored over a two year period following the start of ecosystem-scale manipulations of water table position and surface soil temperatures in a moderate rich fen in interior Alaska. The largest CH4 fluxes occurred in plots that received both flooding (raised water table position) and soil...

Forests of the Oregon Coast Range-considerations for ecological restoration

Treesearch

Joe Means; Shu-hei Chen; Jane Kertis; Pete Teensma

1996-01-01

The Oregon Coast Range supports some of the most dense and productive forests in North America. In the pre-harvesting period these forests arose as a result of large fires-the largest covering 330,000 ha (Teensma and others 1991). These fires occurred mostly at intervals of 150 to 300 years. The natural disturbance regime supported a diverse fauna and large populations...

Community structure, biodiversity, and ecosystem services in treeline whitebark pine communities: Potential impacts from a non-native pathogen

Treesearch

Diana F. Tomback; Lynn M. Resler; Robert E. Keane; Elizabeth R. Pansing; Andrew J. Andrade; Aaron C. Wagner

2016-01-01

Whitebark pine (Pinus albicaulis) has the largest and most northerly distribution of any white pine (Subgenus Strobus) in North America, encompassing 18° latitude and 21° longitude in western mountains. Within this broad range, however, whitebark pine occurs within a narrow elevational zone, including upper subalpine and treeline forests, and functions...

Assessment of national strategies for control of high pathogenicity avian influenza and low pathogenicity notifiable avian influenza in poultry, with emphasis on vaccines and vaccination

USDA-ARS?s Scientific Manuscript database

Twenty-nine distinct epizootics of highly pathogenic avian influenza (HPAI) have occurred since 1959. The H5N1 HPAI panzootic affecting Asia, Africa and Eastern Europe has been the largest among these, affecting poultry and/or wild birds in 63 countries. Historically, control strategies have focus...

Seismicity associated with quiescent-explosive transitions at dome forming eruptions: The July 2008 Vulcanian Explosion of Soufrière Hills Volcano, Montserrat

NASA Astrophysics Data System (ADS)

Rodgers, Mel; Smith, Patrick; Mather, Tamsin A.; Pyle, David M.

2017-04-01

During long-lived dome-forming eruptions volcanoes often transition between quiescent, effusive, and explosive behaviour. Soufrière Hills Volcano (SHV), Montserrat, has been erupting since 1995 and has repeatedly transitioned between these different phases of activity. At SHV many of the largest explosions have occurred either during periods of dome growth, or as major dome collapse events at the end of extrusion phases. However, on the 29th July 2008 a vulcanian explosion marked the transition from a quiescent phase (Pause 3) to explosion and then extrusion. This was one of the largest explosions by volume and the largest to occur outside a period of lava extrusion. The eruption was preceded by one of the most intense seismic swarms ever recorded at SHV. In this study we analysed precursory seismic data to investigate the subsurface volcanic processes that culminated in this eruption. We used spectral and multiplet analysis techniques, and applied a simple parameterization approach to relate monitoring observations (seismic, SO2, visual) to subsurface interpretations. These techniques would be available to most volcano observatories. Our study suggests that an initial VT swarm, coincident with ash-venting events, can be triggered by ascent of decoupled gas ahead of rising magma. A subsequent large LF swarm shows a coincident decrease in spectral content that we interpret as magma ascent through the upper conduit system. An ash-venting event on 27 July (a few hours before peak event rate) may have triggered rapid microlite growth. We observe an increase in the spectral content of the LF swarm that is concurrent with a decrease in event rates, suggesting pressurization of the magmatic system due to inhibited magmatic outgassing. Our results suggest that pressurization of the magmatic system may have occurred in the final 24 h before the vulcanian explosion. We also observe LP and Hybrid events within the same multiplet, suggesting that these events have very similar source processes and should be considered part of the same classification at SHV. Our study demonstrates the potential for using spectral and multiplet analysis to understand subsurface magmatic processes and for investigating the transition between quiescence and eruption.

Multimodal dispersal during the range expansion of the tropical house gecko Hemidactylus mabouia

PubMed Central

Short, Kristen H; Petren, Kenneth

2011-01-01

Dispersal influences both the ecological and evolutionary dynamics of range expansion. While some studies have demonstrated a role for human-mediated dispersal during invasion, the genetic effects of such dispersal remain to be understood, particularly in terrestrial range expansions. In this study, we investigated multimodal dispersal during the range expansion of the invasive gecko Hemidactylus mabouia in Florida using 12 microsatellite loci. We investigated dispersal patterns at the regional scale (metropolitan areas), statewide scale (state of Florida), and global scale (including samples from the native range). Dispersal was limited at the smallest, regional scale, within metropolitan areas, as reflected by the presence of genetic structure at this scale, which is in agreement with a previous study in this same invasion at even smaller spatial scales. Surprisingly, there was no detectable genetic structure at the intermediate statewide scale, which suggests dispersal is not limited across the state of Florida. There was evidence of genetic differentiation between Florida and other areas where H. mabouia occurs, so we concluded that at the largest scale, dispersal was limited. Humans likely contributed to patterns of dispersal at all three scales but in different ways. Infrequent low-volume dispersal has occurred within regions, frequent high-volume dispersal has occurred across the state, and infrequent long-distance dispersal has occurred among continents at the global scale. This study highlights the importance of considering different modes of dispersal at multiple spatial scales to understand the dynamics of invasion and range expansion. PMID:22393494

Statistical Aspects of X-Class Halo and Non-Halo Events, 1996-2014

NASA Technical Reports Server (NTRS)

Wilson, Robert M.

2016-01-01

Of the 166 X-class events that occurred during the interval 1996-2014, 80 had associations with halo events, 68 had no associations with halo events, and 18 occurred during LASCO (Large Angle and Spectrometric COronagraph) data gaps. Both the duration and location of the X-class halo events proved to be statistically important parameters with respect to the geo-effectiveness of the events. Forty-four of the 80 X-class halo events occurred within 45 degrees of the Sun's central meridian and 47 of the 80 had duration greater than or equal to 30 minutes, whereas only 28 of the 68 X-class non-halo events occurred within 45 degrees of the Sun's central meridian (2 events have unknown location) and 22 of the 68 had duration greater than or equal to 30 minutes. Ignoring the 4 largest X-class flares greater than or equal to X4.0 during the LASCO data gaps, 17 of the remaining 20 were associated with halo events, and 14 of the 17 had at least one geo-magnetically disturbed day (Ap (i.e. NOAA's Ap* (ApStar)index: the major magnetic storms going back to 1932) greater than or equal to 25 nanotesias) within 1-5 days following the X-class halo event. Based on the hourly Dst (Disturbance storm time) index, the most geo-effective X-class halo event during the interval 1996-2014 was that of an X1.7 flare that occurred on 2001 March 29 at 0957, having an hourly Disturbance storm time minimum equal to minus 387 nanotesias. On average, the X-class halo events (80 events) were found to have a mean duration (42 minutes) slightly longer than the mean duration (29 minutes) of the X-class non-halo events (68 events) with the difference in the means being statistically important at the 1 percent level of significance.

Large Historical Tsunamigenic Earthquakes in Italy: The Neglected Tsunami Research Point of View

NASA Astrophysics Data System (ADS)

Armigliato, A.; Tinti, S.; Pagnoni, G.; Zaniboni, F.

2015-12-01

It is known that tsunamis are rather rare events, especially when compared to earthquakes, and the Italian coasts are no exception. Nonetheless, a striking evidence is that 6 out of 10 earthquakes occurred in the last thousand years in Italy, and having equivalent moment magnitude equal or larger than 7 where accompanied by destructive or heavily damaging tsunamis. If we extend the lower limit of the equivalent moment magnitude down to 6.5 the percentage decreases (around 40%), but is still significant. Famous events like those occurred on 30 July 1627 in Gargano, on 11 January 1693 in eastern Sicily, and on 28 December 1908 in the Messina Straits are part of this list: they were all characterized by maximum run-ups of several meters (13 m for the 1908 tsunami), significant maximum inundation distances, and large (although not precisely quantifiable) numbers of victims. Further evidences provided in the last decade by paleo-tsunami deposit analyses help to better characterize the tsunami impact and confirm that none of the cited events can be reduced to local or secondary effects. Proper analysis and simulation of available tsunami data would then appear as an obvious part of the correct definition of the sources responsible for the largest Italian tsunamigenic earthquakes, in a process in which different datasets analyzed by different disciplines must be reconciled rather than put into contrast with each other. Unfortunately, macroseismic, seismic and geological/geomorphological observations and data typically are assigned much heavier weights, and in-land faults are often assigned larger credit than the offshore ones, even when evidence is provided by tsunami simulations that they are not at all capable of justifying the observed tsunami effects. Tsunami generation is imputed a-priori to only supposed, and sometimes even non-existing, submarine landslides. We try to summarize the tsunami research point of view on the largest Italian historical tsunamigenic earthquakes; we highlight the open problems, and suggest that tsunami observations and simulations can contribute towards their solution. This study is funded in the frame of the EU Project called ASTARTE - Assessment, STrategy And Risk reduction for Tsunamis in Europe. Grant 603839, 7th FP (ENV.2013.6.4-3).

Ballistic and Diffusive Thermal Conductivity of Graphene

NASA Astrophysics Data System (ADS)

Saito, Riichiro; Masashi, Mizuno; Dresselhaus, Mildred S.

2018-02-01

This paper is a contribution to the Physical Review Applied collection in memory of Mildred S. Dresselhaus. Phonon-related thermal conductivity of graphene is calculated as a function of the temperature and sample size of graphene in which the crossover of ballistic and diffusive thermal conductivity occurs at around 100 K. The diffusive thermal conductivity of graphene is evaluated by calculating the phonon mean free path for each phonon mode in which the anharmonicity of a phonon and the phonon scattering by a 13C isotope are taken into account. We show that phonon-phonon scattering of out-of-plane acoustic phonon by the anharmonic potential is essential for the largest thermal conductivity. Using the calculated results, we can design the optimum sample size, which gives the largest thermal conductivity at a given temperature for applying thermal conducting devices.

Effects of Cohesive Sediment on Estuarine Morphology in Laboratory Scale Experiments

NASA Astrophysics Data System (ADS)

Braat, L.; Leuven, J.; Lokhorst, I.; Kleinhans, M. G.

2017-12-01

Mud plays a major role in forming and filling of river estuaries. River estuaries are typically build of sand and flanked by mudflats, which affect channel-shoal dynamics on time scales of centuries to millennia. In our research we aim to study the effects of mud on the shape and evolution of estuaries and where the largest effects occur. Recently a 20 m by 3 m flume (the Metronome) was developed at Utrecht University for tidal experiments. Complete estuaries are simulated in the Metronome by driving tidal flow by periodically tilting of the flume to counteract scaling problems. To simulate the effects of cohesive mud we supply nutshell grains to the system together with the river discharge. Three scenarios were tested, one with only sand, one with a low supply concentration of nutshell and one with a high concentration (left to right in figure).Estuaries that developed from an initial convergent shape are self-formed through bank erosion, continuous channel-shoal migration and bar and mud flat sedimentation (figure shows development over 15000 tilting cycles). The cohesive sediment deposits occur mainly on bars, but also on the flanks of the estuary and in abandoned channels. Due to its different erosional and depositional characteristics, the nutshell increases the elevation of the bars, which reduces storage and ebb-dominance and causes reduction of bar mobility and short cuts. These results agree with numerical model results. The large-scale effect is less widening of the estuary in the presence of mud and a decrease in channel-shoal migration, suggesting that mud confines estuary width in a similar manner as river floodplains.

Influence of geomagnetic activity and atmospheric pressure in hypertensive adults.

PubMed

Azcárate, T; Mendoza, B

2017-09-01

We performed a study of the systolic and diastolic arterial blood pressure behavior under natural variables such as the atmospheric pressure and the horizontal geomagnetic field component. We worked with a group of eight adult hypertensive volunteers, four men and four women, with ages between 18 and 27 years in Mexico City during a geomagnetic storm in 2014. The data was divided by gender, age, and day/night cycle. We studied the time series using three methods: correlations, bivariate analysis, and superposed epoch (within a window of 2 days around the day of occurrence of a geomagnetic storm) analysis, between the systolic and diastolic blood pressure and the natural variables. The correlation analysis indicated a correlation between the systolic and diastolic blood pressure and the atmospheric pressure and the horizontal geomagnetic field component, being the largest during the night. Furthermore, the correlation and bivariate analyses showed that the largest correlations are between the systolic and diastolic blood pressure and the horizontal geomagnetic field component. Finally, the superposed epoch analysis showed that the largest number of significant changes in the blood pressure under the influence of geomagnetic field occurred in the systolic blood pressure for men.

Influence of geomagnetic activity and atmospheric pressure in hypertensive adults

NASA Astrophysics Data System (ADS)

Azcárate, T.; Mendoza, B.

2017-09-01

We performed a study of the systolic and diastolic arterial blood pressure behavior under natural variables such as the atmospheric pressure and the horizontal geomagnetic field component. We worked with a group of eight adult hypertensive volunteers, four men and four women, with ages between 18 and 27 years in Mexico City during a geomagnetic storm in 2014. The data was divided by gender, age, and day/night cycle. We studied the time series using three methods: correlations, bivariate analysis, and superposed epoch (within a window of 2 days around the day of occurrence of a geomagnetic storm) analysis, between the systolic and diastolic blood pressure and the natural variables. The correlation analysis indicated a correlation between the systolic and diastolic blood pressure and the atmospheric pressure and the horizontal geomagnetic field component, being the largest during the night. Furthermore, the correlation and bivariate analyses showed that the largest correlations are between the systolic and diastolic blood pressure and the horizontal geomagnetic field component. Finally, the superposed epoch analysis showed that the largest number of significant changes in the blood pressure under the influence of geomagnetic field occurred in the systolic blood pressure for men.

Comparison of the November 2002 Denali and November 2001 Kunlun Earthquakes

NASA Astrophysics Data System (ADS)

Bufe, C. G.

2002-12-01

Major earthquakes occurred in Tibet on the central Kunlun fault (M 7.8) on November 14, 2001 (Lin and others, 2002) and in Alaska on the central Denali fault (M 7.9) on November 3, 2002. Both earthquakes generated large surface waves (Kunlun Ms 8.0 (USGS) and Denali Ms 8.5). Each event occurred on east-west-trending strike-slip faults and exhibited nearly unilateral rupture propagating several hundred kilometers from west to east. Surface rupture length estimates were about 400 km for Kunlun, 300 km for Denali. Maximum surface faulting and moment release were observed far to the east of the points of rupture initiation. Harvard moment centroids were located east of USGS epicenters by 182 km (Kunlun) and by 126 km (Denali). Maximum surface faulting was observed near 240 km (Kunlun, 16 m left lateral) and near 175 km (Denali, 9 m right lateral) east of the USGS epicenters. Significant thrust components were observed in the initiation of the Denali event (ERI analysis and mapped thrust) and in the termination of the Kunlun rupture, as evidenced by thrust mechanisms of the largest aftershocks which occurred near the eastern part of the Kunlun rupture. In each sequence the largest aftershock was about 2 orders of magnitude smaller than the mainshock. Moment release along the ruptured segments was examined for the 25-year periods preceding the main shocks. The Denali zone shows precursory accelerating moment release with the dominant events occurring on October 22, 1996 (M 5.8) and October 23, 2002 (M 6.7). The Kunlun zone shows nearly constant moment release over time with the last significant event before the main shock occurring on November 26, 2000 (M 5.4). Moment release data are consistent with previous observations of annual periodicity preceding major earthquakes, possibly due to the evolution of a critical state with seasonal and tidal triggering (Varnes and Bufe, 2001). Annual periodicity is also evident for the larger events in the greater San Francisco Bay region over several decades preceding the 1906 San Francisco earthquake (M 7.8). Both the Kunlun and the Denali mainshocks occurred at new moon.

Sizing ocean giants: patterns of intraspecific size variation in marine megafauna

PubMed Central

Balk, Meghan A.; Benfield, Mark C.; Branch, Trevor A.; Chen, Catherine; Cosgrove, James; Dove, Alistair D.M.; Gaskins, Lindsay C.; Helm, Rebecca R.; Hochberg, Frederick G.; Lee, Frank B.; Marshall, Andrea; McMurray, Steven E.; Schanche, Caroline; Stone, Shane N.; Thaler, Andrew D.

2015-01-01

What are the greatest sizes that the largest marine megafauna obtain? This is a simple question with a difficult and complex answer. Many of the largest-sized species occur in the world’s oceans. For many of these, rarity, remoteness, and quite simply the logistics of measuring these giants has made obtaining accurate size measurements difficult. Inaccurate reports of maximum sizes run rampant through the scientific literature and popular media. Moreover, how intraspecific variation in the body sizes of these animals relates to sex, population structure, the environment, and interactions with humans remains underappreciated. Here, we review and analyze body size for 25 ocean giants ranging across the animal kingdom. For each taxon we document body size for the largest known marine species of several clades. We also analyze intraspecific variation and identify the largest known individuals for each species. Where data allows, we analyze spatial and temporal intraspecific size variation. We also provide allometric scaling equations between different size measurements as resources to other researchers. In some cases, the lack of data prevents us from fully examining these topics and instead we specifically highlight these deficiencies and the barriers that exist for data collection. Overall, we found considerable variability in intraspecific size distributions from strongly left- to strongly right-skewed. We provide several allometric equations that allow for estimation of total lengths and weights from more easily obtained measurements. In several cases, we also quantify considerable geographic variation and decreases in size likely attributed to humans. PMID:25649000

Evolution of the Largest Mammalian Genome.

PubMed

Evans, Ben J; Upham, Nathan S; Golding, Goeffrey B; Ojeda, Ricardo A; Ojeda, Agustina A

2017-06-01

The genome of the red vizcacha rat (Rodentia, Octodontidae, Tympanoctomys barrerae) is the largest of all mammals, and about double the size of their close relative, the mountain vizcacha rat Octomys mimax, even though the lineages that gave rise to these species diverged from each other only about 5 Ma. The mechanism for this rapid genome expansion is controversial, and hypothesized to be a consequence of whole genome duplication or accumulation of repetitive elements. To test these alternative but nonexclusive hypotheses, we gathered and evaluated evidence from whole transcriptome and whole genome sequences of T. barrerae and O. mimax. We recovered support for genome expansion due to accumulation of a diverse assemblage of repetitive elements, which represent about one half and one fifth of the genomes of T. barrerae and O. mimax, respectively, but we found no strong signal of whole genome duplication. In both species, repetitive sequences were rare in transcribed regions as compared with the rest of the genome, and mostly had no close match to annotated repetitive sequences from other rodents. These findings raise new questions about the genomic dynamics of these repetitive elements, their connection to widespread chromosomal fissions that occurred in the T. barrerae ancestor, and their fitness effects-including during the evolution of hypersaline dietary tolerance in T. barrerae. ©The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Some structural aspects of urbanization in Ethiopia.

PubMed

Rafiq, M; Hailemariam, A

1987-07-01

This article studies the emerging patterns of urbanization in Ethiopia. Over the period from 1967-1984, a number of structural changes have occurred which are likely to play a dominant role in the future urban growth in Ethiopia. In spite of its long history of settled population, Ethiopia did not witness sustained growth of urban centers. Ethiopia is 1 of the least urbanized areas in the Third World. A 3rd aspect of urbanization in Ethiopia is the wide range of regional differentials in the level of urbanization. Most of the urban population is concentrated in 2 administrative regions--Shoa and Eritrea. A more balanced urban growth may, inter alia, involve a better spread in terms of higher education, industrialization, provision of health and social services, and the development of communication and commercial infrastructure. Another striking feature of urbanization in Ethiopia is that growth has not been disproportionately concentrated in the largest urban centers. The largest urban centers have not assumed an inordinately higher level of primacy. The basic form of the curve depicting the relationship between the size of a locality and its rank has remained unchanged over the period. The post-revolution land reforms and the new socioeconomic structure emerging from reorganization of the society appear to have a rural-urban migration inhibiting effect. Some of the country's regional differentials may be associated with environmental factors.

Radionuclides in the soil around the largest coal-fired power plant in Serbia: radiological hazard, relationship with soil characteristics and spatial distribution.

PubMed

Ćujić, Mirjana; Dragović, Snežana; Đorđević, Milan; Dragović, Ranko; Gajić, Boško; Miljanić, Šćepan

2015-07-01

Primordial radionuclides, (238)U, (232)Th and (40)K were determined in soil samples collected at two depths (0-10 and 10-20 cm) in the vicinity of the largest coal-fired power plant in Serbia, and their spatial distribution was analysed using ordinary kriging. Mean values of activity concentrations for these depths were 50.7 Bq kg(-1) for (238)U, 48.7 Bq kg(-1) for (232)Th and 560 Bq kg(-1) for (40)K. Based on the measured activity concentrations, the radiological hazard due to naturally occurring radionuclides in soil was assessed. The value of the mean total absorbed dose rate was 76.3 nGy h(-1), which is higher than the world average. The annual effective dose due to these radionuclides ranged from 51.4 to 114.2 μSv. Applying cluster analysis, correlations between radionuclides and soil properties were determined. The distribution pattern of natural radionuclides in the environment surrounding the coal-fired power plant and their enrichment in soil at some sampling sites were in accordance with dispersion models of fly ash emissions. From the results obtained, it can be concluded that operation of the coal-fired power plant has no significant negative impact on the surrounding environment with regard to the content of natural radionuclides.

The effect of guideline variations on the implementation of active management of the third stage of labor.

PubMed

Miranda, Jezid E; Rojas-Suarez, Jose; Paternina, Angel; Mendoza, Ray; Bello, Camilo; Tolosa, Jorge E

2013-06-01

To determine whether healthcare providers performed active management of the third stage of labor (AMTSL) as defined by FIGO/ICM and WHO, and as described by the Cochrane Collaboration. In a prospective observational study, a questionnaire regarding knowledge of AMTSL was administered to healthcare providers in the largest maternity teaching center in Colombia. It was subsequently observed whether and how the healthcare providers performed AMTSL in practice. The percentage of correct use of AMTSL was calculated. Healthcare providers indicated they knew what AMTSL was but disagreed on the timing of prophylactic oxytocin use. In total, 241 deliveries were observed. Oxytocin at varying doses and routes was used in 239 (99.2%) deliveries. In all deliveries, the umbilical cord was clamped early. In 49 (20.3%) deliveries, controlled cord traction was performed. Uterine massage was carried out in 213 (88.4%) deliveries. According to the FIGO/ICM and WHO definitions, and the Cochrane Collaboration description, correct use of AMTSL occurred in 0.8%, 0.0%, and 8.3%, of cases, respectively. Correct use of AMTSL is low at the largest maternity teaching center in Colombia. There is an urgent need for a single definition of AMTSL, which could be used globally for research, training, and scaling-up the performance of AMTSL. Copyright © 2013 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.

Insertion of bentonite with Organometallic [Fe3O(OOC6H5)6(H2O)3(NO3).nH2O] as Adsorbent of Congo Red

NASA Astrophysics Data System (ADS)

Said, Muhammad; Paluta Utami, Hasja; Hayati, Ferlina

2018-01-01

The adsorption of Congo red using bentonite inserted organometallic has been investigated. The insertion bentonite was characterized using FT-IR Spectrophotometer, XRD and XRF analysis. The FT-IR characterization showed the higher intensity of peak wavenumber at 470.6 cm-1 for Fe3O on the ratio 1:3. While the XRD characterization showed the shift of diffraction angle of 2θ was 5.2° and has a basal spacing of 16.8 Å. In the XRF characterization, the insertion process of organometallic occurred optimally with the percentage of metal oxide reached 71.75 %. The adsorption process of bentonite inserted organometallic compound [Fe3O(OOC6H5)6(H2O)3(NO3)·nH2O] showed the adsorption rate (k) is 0.050 min-1, the largest adsorption capacity (b) at 70°C is 4.48 mol/g, the largest adsorption energy at temperature 30°C which is 6.4 kJ/mol Organometallic compounds. The value of the enthalpy (ΔH) and entropy (ΔS) decreased with increasing concentrations of the Congo red. Effect of pH on the adsorption on at pH 3 shows the biggest of number Congo red absorbed is 19.52 mg/L for insertion of bentonite.

Characterization and swelling-deswelling properties of wheat straw cellulose based semi-IPNs hydrogel.

PubMed

Liu, Jia; Li, Qian; Su, Yuan; Yue, Qinyan; Gao, Baoyu

2014-07-17

A novel wheat straw cellulose-g-poly(potassium acrylate)/polyvinyl alcohol (WSC-g-PKA/PVA) semi-interpenetrating polymer networks (semi-IPNs) hydrogel was prepared by polymerizing wheat straw and an aqueous solution of acrylic acid (AA), and further semi-interpenetrating with PVA occurred during the chemosynthesis. The swelling and deswelling properties of WSC-g-PKA/PVA semi-IPNs hydrogel and WSC-g-PKA hydrogel were studied and compared in various pH solutions, salt solutions, temperatures, particle sizes and ionic strength. The results indicated that both hydrogels had the largest swelling capacity at pH=6, and the effect of ions on the swelling of hydrogels was in the order: Na(+)>K(+)>Mg(2+)>Ca(2+). The Schott's pseudo second order model can be effectively used to evaluate swelling kinetics of hydrogels. Moreover, the semi-IPNs hydrogel had improved swelling-deswelling properties compared with that of WSC-g-PKA hydrogel. Copyright © 2014 Elsevier Ltd. All rights reserved.

Magnetic, thermal, and optical properties of single-crystalline CoTa2O6 and FeTa2O6 and their anisotropic magnetocaloric effect.

PubMed

Christian, A B; Schye, A T; White, K O; Neumeier, J J

2018-05-16

The magnetic, thermal, and optical properties of single-crystalline CoTa 2 O 6 and FeTa 2 O 6 are reported. Optical dichroism was observed in CoTa 2 O 6 . Magnetic susceptibility χ(T) measurements reveal long-range antiferromagnetic order with Néel temperatures [Formula: see text] K and 8.11(5) K, respectively, and anisotropy in χ. The thermal expansion coefficients exhibit significant anisotropy and the influence of the magnetic ions and long-range order. A structural phase transition to orthorhombic occurs below T N for FeTa 2 O 6 . Magnetic field H lowers T N with its affect largest when H is directed along either [1 1 0] or [1 [Formula: see text] 0], and smallest when directed along [0 0 1]. This leads to an anisotropic magnetocaloric effect that is investigated through measurements of the specific heat and magnetization in applied magnetic field.

Magnetic, thermal, and optical properties of single-crystalline CoTa2O6 and FeTa2O6 and their anisotropic magnetocaloric effect

NASA Astrophysics Data System (ADS)

Christian, A. B.; Schye, A. T.; White, K. O.; Neumeier, J. J.

2018-05-01

The magnetic, thermal, and optical properties of single-crystalline CoTa2O6 and FeTa2O6 are reported. Optical dichroism was observed in CoTa2O6. Magnetic susceptibility χ(T) measurements reveal long-range antiferromagnetic order with Néel temperatures K and 8.11(5) K, respectively, and anisotropy in χ. The thermal expansion coefficients exhibit significant anisotropy and the influence of the magnetic ions and long-range order. A structural phase transition to orthorhombic occurs below T N for FeTa2O6. Magnetic field H lowers T N with its affect largest when H is directed along either [1 1 0] or [1  0], and smallest when directed along [0 0 1]. This leads to an anisotropic magnetocaloric effect that is investigated through measurements of the specific heat and magnetization in applied magnetic field.

A comparison of bilateral versus unilateral target and distractor presentation in the remote distractor paradigm.

PubMed

Benson, Valerie

2008-01-01

The remote distractor effect (RDE) is a robust finding of an increase in saccade onset latencies (20-40 ms) when a distractor is presented simultaneously with a target, compared to when a target is presented on its own (Walker, Deubel, Schneider, & Findlay, 1997). Distractors presented at fixation produce the largest RDE and the effect decreases as distractors are moved into the periphery. Data from two experiments that contrast with these standard findings are reported. Under bilateral target presentation, larger RDE magnitudes occurred for peripheral than for central distractors, whereas under unilateral presentation, the pattern reversed. The findings are discussed with reference to discrimination processes, attentional factors and current models of oculomotor control. It is suggested that in bilateral target presentation the competition between the distractor and the target results in the programming of a saccade to the distractor, as well as a saccade to the target. Time taken to cancel the saccade to the distractor produces the increased saccade latency for peripheral distractors in that condition.

Successive Magnetic-Field-Induced Transitions and Colossal Magnetoelectric Effect in Ni 3 TeO 6

DOE PAGES

Kim, Jae Wook; Artyukhin, Sergei; Mun, Eun Deok; ...

2015-09-24

In this paper, we report the discovery of a metamagnetic phase transition in a polar antiferromagnet Ni 3TeO 6 that occurs at 52 T. The new phase transition accompanies a colossal magnetoelectric effect, with a magnetic-field-induced polarization change of 0.3 μC/cm 2, a value that is 4 times larger than for the spin-flop transition at 9 T in the same material, and also comparable to the largest magnetically induced polarization changes observed to date. Via density-functional calculations we construct a full microscopic model that describes the data. We model the spin structures in all fields and clarify the physics behindmore » the 52 T transition. The high-field transition involves a competition between multiple different exchange interactions which drives the polarization change through the exchange-striction mechanism. Finally, the resultant spin structure is rather counterintuitive and complex, thus providing new insights on design principles for materials with strong magnetoelectric coupling.« less

Post-Disaster Fertility: Hurricane Katrina and the Changing Racial Composition of New Orleans

PubMed Central

Seltzer, Nathan; Nobles, Jenna

2017-01-01

Large-scale climate events can have enduring effects on population size and composition. Natural disasters affect population fertility through multiple mechanisms, including displacement, demand for children, and reproductive care access. Fertility effects, in turn, influence the size and composition of new birth cohorts, extending the reach of climate events across generations. We study these processes in New Orleans during the decade spanning Hurricane Katrina. We combine census data, ACS data, and vital statistics data to describe fertility in New Orleans and seven comparison cities. Following Katrina, displacement contributed to a 30% decline in birth cohort size. Black fertility fell, and remained 4% below expected values through 2010. By contrast, white fertility increased by 5%. The largest share of births now occurs to white women. These fertility differences—beyond migration-driven population change—generate additional pressure on the renewal of New Orleans as a city in which the black population is substantially smaller in the disaster’s wake. PMID:29200546

Post-Disaster Fertility: Hurricane Katrina and the Changing Racial Composition of New Orleans.

PubMed

Seltzer, Nathan; Nobles, Jenna

2017-06-01

Large-scale climate events can have enduring effects on population size and composition. Natural disasters affect population fertility through multiple mechanisms, including displacement, demand for children, and reproductive care access. Fertility effects, in turn, influence the size and composition of new birth cohorts, extending the reach of climate events across generations. We study these processes in New Orleans during the decade spanning Hurricane Katrina. We combine census data, ACS data, and vital statistics data to describe fertility in New Orleans and seven comparison cities. Following Katrina, displacement contributed to a 30% decline in birth cohort size. Black fertility fell, and remained 4% below expected values through 2010. By contrast, white fertility increased by 5%. The largest share of births now occurs to white women. These fertility differences-beyond migration-driven population change-generate additional pressure on the renewal of New Orleans as a city in which the black population is substantially smaller in the disaster's wake.

How do rituals affect cooperation? An experimental field study comparing nine ritual types.

PubMed

Fischer, Ronald; Callander, Rohan; Reddish, Paul; Bulbulia, Joseph

2013-06-01

Collective rituals have long puzzled anthropologists, yet little is known about how rituals affect participants. Our study investigated the effects of nine naturally occurring rituals on prosociality. We operationalized prosociality as (1) attitudes about fellow ritual participants and (2) decisions in a public goods game. The nine rituals varied in levels of synchrony and levels of sacred attribution. We found that rituals with synchronous body movements were more likely to enhance prosocial attitudes. We also found that rituals judged to be sacred were associated with the largest contributions in the public goods game. Path analysis favored a model in which sacred values mediate the effects of synchronous movements on prosocial behaviors. Our analysis offers the first quantitative evidence for the long-standing anthropological conjecture that rituals orchestrate body motions and sacred values to support prosociality. Our analysis, moreover, adds precision to this old conjecture with evidence of a specific mechanism: ritual synchrony increases perceptions of oneness with others, which increases sacred values to intensify prosocial behaviors.

Interspecific competition in tributaries: Prospectus for restoring Atlantic salmon in Lake Ontario

USGS Publications Warehouse

Johnson, James H.; Wedge, Leslie R.

1999-01-01

Historically, Lake Ontario may have supported the world's largest freshwater population of Atlantic salmon (Salmo salar). However, by the late 1800's, salmon were virtually extinct in the lake due to the damming of tributaries, overharvest, deforestation, and pollution. Of these factors, the building of dams on tributaries, which precluded access by the salmon to natal spawning streams, was probably the most detrimental. Since the extirpation of Atlantic salmon in the Lake Ontario watershed over a century ago, considerable change has occurred throughout the lake and tributary ecosystem. The changes within the ecosystem that may have the most profound effect on Atlantic salmon restoration include the presence of exotic species, including other salmonines, and reduced habitat quality, especially in tributaries. These changes must be taken into account when considering Atlantic salmon restoration.

More tornadoes in the most extreme U.S. tornado outbreaks.

PubMed

Tippett, Michael K; Lepore, Chiara; Cohen, Joel E

2016-12-16

Tornadoes and severe thunderstorms kill people and damage property every year. Estimated U.S. insured losses due to severe thunderstorms in the first half of 2016 were $8.5 billion (US). The largest U.S. effects of tornadoes result from tornado outbreaks, which are sequences of tornadoes that occur in close succession. Here, using extreme value analysis, we find that the frequency of U.S. outbreaks with many tornadoes is increasing and that it is increasing faster for more extreme outbreaks. We model this behavior by extreme value distributions with parameters that are linear functions of time or of some indicators of multidecadal climatic variability. Extreme meteorological environments associated with severe thunderstorms show consistent upward trends, but the trends do not resemble those currently expected to result from global warming. Copyright © 2016, American Association for the Advancement of Science.

Exergy analysis of biomass organic Rankine cycle for power generation

NASA Astrophysics Data System (ADS)

Nur, T. B.; Sunoto

2018-02-01

The study examines proposed small biomass-fed Organic Rankine Cycle (ORC) power plant through exergy analysis. The system consists of combustion burner unit to utilize biomass as fuel, and organic Rankine cycle unit to produce power from the expander. The heat from combustion burner was transfered by thermal oil heater to evaporate ORC working fluid in the evaporator part. The effects of adding recuperator into exergy destruction were investigated. Furthermore, the results of the variations of system configurations with different operating parameters, such as the evaporating pressures, ambient temperatures, and expander pressures were analyzed. It was found that the largest exergy destruction occurs during processes are at combustion part, followed by evaporator, condenser, expander, and pump. The ORC system equipped with a recuperator unit exhibited good operational characteristics under wide range conditions compared to the one without recuperator.

Oil, Water, and Wildlife: The Gulf of Mexico Disaster and Related Environmental Issues

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bickman, John W.

2010-08-04

The BP Macondo oil field spill in the Gulf of Mexico is the largest oil spill in U.S. history and has the potential to impact sea turtle and marine mammal populations, and others. This presentation will review the genotoxic effects of oil exposure in wildlife and discuss the potential for an oil spill to impact wildlife populations. Whereas some aspects of a spill are predictable, each spill is different because oils are highly variable, as are the environments in which they occur. The presentation will discuss what has been learned from previous spills, including the Exxon Valdez and the sovietmore » oil legacy in Azerbaijan, and the potential dangers of offshore oil development in the Arctic. Related Purdue University research efforts in oil-spill related engineering and science also will be highlighted.« less

Oil, Water, and Wildlife: The Gulf of Mexico Disaster and Related Environmental Issues

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bickman, John W.

The BP Macondo oil field spill in the Gulf of Mexico is the largest oil spill in U.S. history and has the potential to impact sea turtle and marine mammal populations, and others. This presentation will review the genotoxic effects of oil exposure in wildlife and discuss the potential for an oil spill to impact wildlife populations. Whereas some aspects of a spill are predictable, each spill is different because oils are highly variable, as are the environments in which they occur. The presentation will discuss what has been learned from previous spills, including the Exxon Valdez and the sovietmore » oil legacy in Azerbaijan, and the potential dangers of offshore oil development in the Arctic. Related Purdue University research efforts in oil-spill related engineering and science also will be highlighted.« less

Beyond the Census Tract: Patterns and Determinants of Racial Segregation at Multiple Geographic Scales*

PubMed Central

Lee, Barrett A.; Reardon, Sean F.; Firebaugh, Glenn; Farrell, Chad R.; Matthews, Stephen A.; O'Sullivan, David

2014-01-01

The census tract-based residential segregation literature rests on problematic assumptions about geographic scale and proximity. We pursue a new tract-free approach that combines explicitly spatial concepts and methods to examine racial segregation across egocentric local environments of varying size. Using 2000 census data for the 100 largest U.S. metropolitan areas, we compute a spatially modified version of the information theory index H to describe patterns of black-white, Hispanic-white, Asian-white, and multi-group segregation at different scales. The metropolitan structural characteristics that best distinguish micro-segregation from macro-segregation for each group combination are identified, and their effects are decomposed into portions due to racial variation occurring over short and long distances. A comparison of our results to those from tract-based analyses confirms the value of the new approach. PMID:25324575

Oil, Water, and Wildlife: The Gulf of Mexico Disaster and Related Environmental Issues

ScienceCinema

Bickman, John W. [Purdue University, West Lafayette, Indiana, United States

2017-12-09

The BP Macondo oil field spill in the Gulf of Mexico is the largest oil spill in U.S. history and has the potential to impact sea turtle and marine mammal populations, and others. This presentation will review the genotoxic effects of oil exposure in wildlife and discuss the potential for an oil spill to impact wildlife populations. Whereas some aspects of a spill are predictable, each spill is different because oils are highly variable, as are the environments in which they occur. The presentation will discuss what has been learned from previous spills, including the Exxon Valdez and the soviet oil legacy in Azerbaijan, and the potential dangers of offshore oil development in the Arctic. Related Purdue University research efforts in oil-spill related engineering and science also will be highlighted.

Gates Foundation donates $25 million for AIDS vaccine.

PubMed

1999-05-07

The International AIDS Vaccine Initiative (IAVI) received a $25 million five-year grant from Bill and Melinda Gates through the William H. Gates Foundation. This is the largest gift seen in the AIDS epidemic, and will allow IAVI to more than double vaccine development efforts. IAVI is currently developing two potential vaccines, hopes to study three others, and is working with the business community to insure that a successful vaccine is affordable in developing countries. With 16,000 new infections occurring daily, a vaccine is seen as the most effective way to stop the epidemic. The William H. Gates Foundation had donated $1.5 million to IAVI and $100 million for programs to speed the delivery of vaccines to children in poor countries. Internet addresses are included for both IAVI and the William H. Gates Foundation.

Status and ecological effects of the world's largest carnivores.

PubMed

Ripple, William J; Estes, James A; Beschta, Robert L; Wilmers, Christopher C; Ritchie, Euan G; Hebblewhite, Mark; Berger, Joel; Elmhagen, Bodil; Letnic, Mike; Nelson, Michael P; Schmitz, Oswald J; Smith, Douglas W; Wallach, Arian D; Wirsing, Aaron J

2014-01-10

Large carnivores face serious threats and are experiencing massive declines in their populations and geographic ranges around the world. We highlight how these threats have affected the conservation status and ecological functioning of the 31 largest mammalian carnivores on Earth. Consistent with theory, empirical studies increasingly show that large carnivores have substantial effects on the structure and function of diverse ecosystems. Significant cascading trophic interactions, mediated by their prey or sympatric mesopredators, arise when some of these carnivores are extirpated from or repatriated to ecosystems. Unexpected effects of trophic cascades on various taxa and processes include changes to bird, mammal, invertebrate, and herpetofauna abundance or richness; subsidies to scavengers; altered disease dynamics; carbon sequestration; modified stream morphology; and crop damage. Promoting tolerance and coexistence with large carnivores is a crucial societal challenge that will ultimately determine the fate of Earth's largest carnivores and all that depends upon them, including humans.

The white-margined penstemon (Penstemon albomarginatus Jones), a rare Mohave Desert species, and the Hualapai Mountains land exchange in Mohave County, Arizona

Treesearch

John L. Anderson

2001-01-01

The white-margined penstemon (Penstemon albomarginatus Jones) is a rare Mohave Desert species with an unusual tripartite distribution with disjunct localities in Arizona, California, and Nevada. The Arizona population is the largest single population occurring with a range of 15 miles by 5 miles in Dutch Flat near Yucca, Arizona in Mohave County. The land ownership...

Virulence for mice, resistance to synthetic gastric fluid, and biofilm formation of Listeria monocytogenes H7550, a serotype 4b strain isolated from frankfurters associated with the BilMar listeriosis outbreak

USDA-ARS?s Scientific Manuscript database

Introduction: One of the largest and most severe listeriosis outbreaks in the United States occurred in 1998 as a result of contamination of frankfurters with a serotype 4b strain of Listeria monocytogenes. However, there has been little characterization of the virulence attributes of strains reta...

Regional Seismic Studies in Central Asia

DTIC Science & Technology

1994-01-17

volcanism occurred over a 5 to 10 million year duration, much longer than the duration of the Deccan Traps or Columbia River flood basalts and...the site of the Siberian Traps flhod basalts. These flows possibly represent the largest Mesozoic occurrence of conitinental flood .basalt, and now...areas of continental flood basalts [White & McKenzie, 1989] nor is there a clear connection between tEle Siberian Traps and a mantle hot spot although

Survival of Phytophthora ramorum following wildfires in the sudden oak death-impacted forests of the Big Sur region

Treesearch

Maia M. Beh; Margaret Metz; Kerri Frangioso; David Rizzo

2013-01-01

The summer of 2008 brought the first wildfires to occur in known Phytophthora ramorum-infested forests in California, with the largest individual fire burning in the Big Sur region of the central coast (Monterey County) (Metz et al. 2011). More than 100,000 ha in Big Sur were ultimately burned that summer, providing a natural experiment to examine...

Spatial and temporal variability of interhemispheric transport times

NASA Astrophysics Data System (ADS)

Wu, Xiaokang; Yang, Huang; Waugh, Darryn W.; Orbe, Clara; Tilmes, Simone; Lamarque, Jean-Francois

2018-05-01

The seasonal and interannual variability of transport times from the northern midlatitude surface into the Southern Hemisphere is examined using simulations of three idealized age tracers: an ideal age tracer that yields the mean transit time from northern midlatitudes and two tracers with uniform 50- and 5-day decay. For all tracers the largest seasonal and interannual variability occurs near the surface within the tropics and is generally closely coupled to movement of the Intertropical Convergence Zone (ITCZ). There are, however, notable differences in variability between the different tracers. The largest seasonal and interannual variability in the mean age is generally confined to latitudes spanning the ITCZ, with very weak variability in the southern extratropics. In contrast, for tracers subject to spatially uniform exponential loss the peak variability tends to be south of the ITCZ, and there is a smaller contrast between tropical and extratropical variability. These differences in variability occur because the distribution of transit times from northern midlatitudes is very broad and tracers with more rapid loss are more sensitive to changes in fast transit times than the mean age tracer. These simulations suggest that the seasonal-interannual variability in the southern extratropics of trace gases with predominantly NH midlatitude sources may differ depending on the gases' chemical lifetimes.

New SIMS U-Pb age constraints on the largest lake transgression event in the Songliao Basin, NE China.

PubMed

Xi, Dangpeng; He, Huaiyu; Yu, Zhiqiang; Huang, Qinghua; Hu, Jianfang; Xu, Yankang; Shi, Zhongye; Qin, Zuohuan; Wan, Xiaoqiao

2018-01-01

The largest lake transgression event (LTE) associated with lake anoxic events (LAE) and periodic seawater incursion events (SWIE) in the Songliao Basin, northeastern China, occurred during deposition of the Cretaceous Nenjiang Formation. The Yaojia-Nenjiang Formation boundary (YNB) marks the beginning of the LTE, as well as LAE and SWIE. However, there is an absence of direct radioisotopic dating, and therefore the age of the YNB, as well as the beginning of LTE, together with their relationship with other geological events, is strongly debated. Here we present a new SIMS U-Pb zircon age from the lowermost Nenjiang Formation. The bentonite bed located 9.88 m above the YNB of the X1-4 borehole was analyzed. Twenty-five analyses of 25 zircons were conducted, which produced a weighted mean age of 85.5±0.6 Ma (MSWD = 0.87). Based on the average sediment accumulation rate, the age of the YNB is suggested to be 85.7 Ma, indicating that the LTE began in the Early Santonian. The new ages provide a precise chronostratigraphic framework for climatic and geological events. Our new results imply that the beginning of the LTE, LAE and SWIE occurred almost simultaneously with short-term sea level rise, and probably had a close relationship with OAE3.

Solar Eruptive Activity at Mars' Orbit and its Potential Impacts

NASA Astrophysics Data System (ADS)

Luhmann, J. G.; Lee, C. O.; Curry, S.; Hara, T.; Halekas, J. S.; Li, Y.; Dong, C.; Ma, Y.; Lillis, R. J.; Dunn, P.; Gruesbeck, J.; Espley, J. R.; Brain, D.; Connerney, J. E. P.; Larson, D. E.; Jakosky, B. M.; Russell, C. T.

2016-12-01

While a number of studies exist relating to ICME signatures at Venus (PVO and VEX) and Mercury (Helios and Messenger), relatively few analyses exist for Mars' orbit. Nevertheless plasma and field signatures of ICMEs have been observed in the space near Mars by Phobos-2, Mars Global Surveyor (MGS), Mars Express (MEX), and now MAVEN. Of these, MAVEN is arguably best-instrumented, space weather-wise, to characterize such events. However, the weak solar activity over the past decade has limited what MAVEN, whose mission is to study Mars' atmospheric response to solar activity, including escape to space, has been able to observe. While the major October 1989 event, that produced at Earth one of the largest geomagnetic storms on record, occurred during the short Phobos-2 mission, and the notable series of Halloween 2003 storms occurred during the MGS mission, MAVEN has detected only moderate solar eruptive activity-related interplanetary disturbances at Mars. We compare the largest ICME observed by MAVEN with some of these other more extreme activity episodes for perspective. These comparisons hint at the potential impact of the magnitude of solar eruptions on what is experienced at Mars orbit, and on our ability to investigate planetary responses over the full range -when missions are at the mercy of what the solar cycle produces during their lifetimes.

Giant Upper Cretaceous oysters from the Gulf coast and Caribbean

USGS Publications Warehouse

Sohl, Norman F.; Kauffman, Erle G.

1964-01-01

Two unusually massive ostreid species, representing the largest and youngest Mesozoic members of their respective lineages, occur in Upper Cretaceous sediment of the gulf coast and Caribbean areas. Their characteristics and significance, as well as the morphologic terminology of ostreids in general, are discussed. Crassostrea cusseta Sohl and Kauffman n. sp. is the largest known ostreid from Mesozoic rocks of North America; it occurs sporadically in the Cusseta Sand and rarely in the Blufftown Formation of the Chattahoochee River region in Georgia and Alabama. It is especially notable in that it lacks a detectable posterior adductor muscle scar on large adult shells. C. cusseta is the terminal Cretaceous member of the C. soleniscus lineage in gulf coast sediments; the lineage continues, however, with little basic modification, throughout the Cenozoic, being represented in the Eocene by C. gigantissima (Finch) and probably, in modern times, by C. virginica (Gmelin). The C. soleniscus lineage is the first typically modern crassostreid group recognized in the Mesozoic. Arctostrea aguilerae (Böse) occurs in Late Campanian and Early Maestrichtian sediments of Alabama, Mississippi, Texas(?), Mexico, and Cuba. The mature shell of this species is larger and more massive than that of any other known arctostreid. Arctostrea is well represented throughout the Upper Jurassic and Cretaceous of Europe, but in North America, despite the great numbers and diversity of Cretaceous oysters, only A. aguilerae and the Albian form A. carinata are known. The presence of A. aquilerae in both the Caribbean and gulf coast faunas is exceptional, as the Late Cretaceous faunas of these provinces are generally distinct and originated in different faunal realms.

Abrupt climate change and collapse of deep-sea ecosystems

USGS Publications Warehouse

Yasuhara, Moriaki; Cronin, T. M.; Demenocal, P.B.; Okahashi, H.; Linsley, B.K.

2008-01-01

We investigated the deep-sea fossil record of benthic ostracodes during periods of rapid climate and oceanographic change over the past 20,000 years in a core from intermediate depth in the northwestern Atlantic. Results show that deep-sea benthic community "collapses" occur with faunal turnover of up to 50% during major climatically driven oceanographic changes. Species diversity as measured by the Shannon-Wiener index falls from 3 to as low as 1.6 during these events. Major disruptions in the benthic communities commenced with Heinrich Event 1, the Inter-Aller??d Cold Period (IACP: 13.1 ka), the Younger Dryas (YD: 12.9-11.5 ka), and several Holocene Bond events when changes in deep-water circulation occurred. The largest collapse is associated with the YD/IACP and is characterized by an abrupt two-step decrease in both the upper North Atlantic Deep Water assemblage and species diversity at 13.1 ka and at 12.2 ka. The ostracode fauna at this site did not fully recover until ???8 ka, with the establishment of Labrador Sea Water ventilation. Ecologically opportunistic slope species prospered during this community collapse. Other abrupt community collapses during the past 20 ka generally correspond to millennial climate events. These results indicate that deep-sea ecosystems are not immune to the effects of rapid climate changes occurring over centuries or less. ?? 2008 by The National Academy of Sciences of the USA.

Knowledge does not protect against illusory truth.

PubMed

Fazio, Lisa K; Brashier, Nadia M; Payne, B Keith; Marsh, Elizabeth J

2015-10-01

In daily life, we frequently encounter false claims in the form of consumer advertisements, political propaganda, and rumors. Repetition may be one way that insidious misconceptions, such as the belief that vitamin C prevents the common cold, enter our knowledge base. Research on the illusory truth effect demonstrates that repeated statements are easier to process, and subsequently perceived to be more truthful, than new statements. The prevailing assumption in the literature has been that knowledge constrains this effect (i.e., repeating the statement "The Atlantic Ocean is the largest ocean on Earth" will not make you believe it). We tested this assumption using both normed estimates of knowledge and individuals' demonstrated knowledge on a postexperimental knowledge check (Experiment 1). Contrary to prior suppositions, illusory truth effects occurred even when participants knew better. Multinomial modeling demonstrated that participants sometimes rely on fluency even if knowledge is also available to them (Experiment 2). Thus, participants demonstrated knowledge neglect, or the failure to rely on stored knowledge, in the face of fluent processing experiences. (c) 2015 APA, all rights reserved).

Long-term follow-up of botulinum toxin therapy for focal hand dystonia: outcome at 10 years or more.

PubMed

Lungu, Codrin; Karp, Barbara I; Alter, Katharine; Zolbrod, Regina; Hallett, Mark

2011-03-01

Previous studies have explored the efficacy and safety of botulinum neurotoxin (BoNT) treatment for Focal hand dystonia (FHD), but none have followed a large number of patients for 10 years or more. Retrospective study, with benefit and weakness assessed on a 0 to 4 subjective scale. Demographic, clinical and treatment characteristics were analyzed using t tests and Pearson correlations. Twenty FHD patients had 10 years or longer treatment. Interinjection intervals were variable. Musicians were more likely to wait longer between injections and had less complex dystonia. There was a trend for larger benefit in women and with shorter intervals. The dose increased over time. Dystonia characteristics did not predict response or side-effects, but benefit magnitude predicted longer compliance. No serious side-effects or antibody-mediated resistance occurred. This is the longest reported period of BoNT treatment in the largest FHD cohort. BoNT therapy for FHD remains safe and effective after more than a decade of treatment. Copyright © 2011 Movement Disorder Society.

Effect of winter school breaks on influenza-like illness, Argentina, 2005-2008.

PubMed

Garza, Roberto C; Basurto-Dávila, Ricardo; Ortega-Sanchez, Ismael R; Carlino, Luis Oreste; Meltzer, Martin I; Albalak, Rachel; Balbuena, Karina; Orellano, Pablo; Widdowson, Marc-Alain; Averhoff, Francisco

2013-06-01

School closures are used to reduce seasonal and pandemic influenza transmission, yet evidence of their effectiveness is sparse. In Argentina, annual winter school breaks occur during the influenza season, providing an opportunity to study this intervention. We used 2005-2008 national weekly surveillance data of visits to a health care provider for influenza-like illness (ILI) from all provinces. Using Serfling-specified Poisson regressions and population-based census denominators, we developed incidence rate ratios (IRRs) for the 3 weeks before, 2 weeks during, and 3 weeks after the break. For persons 5-64 years of age, IRRs were <1 for at least 1 week after the break. Observed rates returned to expected by the third week after the break; overall decrease among persons of all ages was 14%. The largest decrease was among children 5-14 years of age during the week after the break (37% lower IRR). Among adults, effects were weaker and delayed. Two-week winter school breaks significantly decreased visits to a health care provider for ILI among school-aged children and nonelderly adults.

Effect of Winter School Breaks on Influenza-like Illness, Argentina, 2005–2008

PubMed Central

Basurto-Dávila, Ricardo; Ortega-Sanchez, Ismael R.; Carlino, Luis Oreste; Meltzer, Martin I.; Albalak, Rachel; Balbuena, Karina; Orellano, Pablo; Widdowson, Marc-Alain; Averhoff, Francisco

2013-01-01

School closures are used to reduce seasonal and pandemic influenza transmission, yet evidence of their effectiveness is sparse. In Argentina, annual winter school breaks occur during the influenza season, providing an opportunity to study this intervention. We used 2005–2008 national weekly surveillance data of visits to a health care provider for influenza-like illness (ILI) from all provinces. Using Serfling-specified Poisson regressions and population-based census denominators, we developed incidence rate ratios (IRRs) for the 3 weeks before, 2 weeks during, and 3 weeks after the break. For persons 5–64 years of age, IRRs were <1 for at least 1 week after the break. Observed rates returned to expected by the third week after the break; overall decrease among persons of all ages was 14%. The largest decrease was among children 5–14 years of age during the week after the break (37% lower IRR). Among adults, effects were weaker and delayed. Two-week winter school breaks significantly decreased visits to a health care provider for ILI among school-aged children and nonelderly adults. PMID:23735682

Massive Mortality of a Planktivorous Seabird in Response to a Marine Heatwave: A Citizen Science Case-study

NASA Astrophysics Data System (ADS)

Jones, T.; Parrish, J.; MacCready, P.; Peterson, W. T.; Bjorkstedt, E.; Bond, N. A.; Ballance, L. T.; Bowes, V.; Hipfner, J. M.; Lindquist, K.; Lindsey, J.; Nevins, H. M.; Burgess, H. K.; Robertson, R.; Roletto, J.; Wilson, L.; Joyce, T. W.; Harvey, J.

2017-12-01

Citizen science data collection is a powerful tool for documenting mass mortality events, as they often occur without warning and can be extensive in space, precluding standard methods of data collection. The Coastal Observation and Seabird Survey Team (COASST) is one such citizen science program that specializes in the collection of information on beachcast seabird abundance and identity. Using the COASST dataset, in combination with federal monitoring data and novel modeling techniques, we investigated the 2014/15 mass mortality event of Cassin's Auklets (Ptychoramphus aleuticus), a small zooplanktivorous seabird, that occurred during the largest marine heatwave (MHW) ever recorded - the NE Pacific MHW of 2014-2016. Estimated at 275,000-530,000 birds, or 11% of the global adult population, and spanning 2,000 km of the North American Pacific coastline, this marine bird die-off is among the largest ever recorded. Carcass deposition followed an effective reduction in the energy content of zooplankton, coincident with the loss of cold-water foraging habitat caused by the intrusion of the NE Pacific MHW. Models examining interannual variability in effort-controlled carcass abundance (2001-2014) identified the biomass of lipid-poor zooplankton as the primary predictor of increased carcass abundance, suggesting that the relative abundance of smaller, lipid-poor zooplankton is a strong predictor of Cassin's Auklets overwinter survival. Furthermore, dispersing Cassin's Auklets were likely compressed into a nearshore band of upwelled water, and ultimately died from starvation following the shift in zooplankton composition associated with the onshore transport of the NE Pacific MHW. The information regarding the magnitude of this event, as well as its causal mechanism, comes as a direct result of rigorous data collection by citizen science volunteers, demonstrating that citizen science can, and does, contribute to our understanding of how climate change is altering marine ecosystems.

Water-quality characteristics, including sodium-adsorption ratios, for four sites in the Powder River drainage basin, Wyoming and Montana, water years 2001-2004

USGS Publications Warehouse

Clark, Melanie L.; Mason, Jon P.

2006-01-01

The U.S. Geological Survey, in cooperation with the Wyoming Department of Environmental Quality, monitors streams throughout the Powder River structural basin in Wyoming and parts of Montana for potential effects of coalbed natural gas development. Specific conductance and sodium-adsorption ratios may be larger in coalbed waters than in stream waters that may receive the discharge waters. Therefore, continuous water-quality instruments for specific conductance were installed and discrete water-quality samples were collected to characterize water quality during water years 2001-2004 at four sites in the Powder River drainage basin: Powder River at Sussex, Wyoming; Crazy Woman Creek near Arvada, Wyoming; Clear Creek near Arvada, Wyoming; and Powder River at Moorhead, Montana. During water years 2001-2004, the median specific conductance of 2,270 microsiemens per centimeter at 25 degrees Celsius (?S/cm) in discrete samples from the Powder River at Sussex, Wyoming, was larger than the median specific conductance of 1,930 ?S/cm in discrete samples collected downstream from the Powder River at Moorhead, Montana. The median specific conductance was smallest in discrete samples from Clear Creek (1,180 ?S/cm), which has a dilution effect on the specific conductance for the Powder River at Moorhead, Montana. The daily mean specific conductance from continuous water-quality instruments during the irrigation season showed the same spatial pattern as specific conductance values for the discrete samples. Dissolved sodium, sodium-adsorption ratios, and dissolved solids generally showed the same spatial pattern as specific conductance. The largest median sodium concentration (274 milligrams per liter) and the largest range of sodium-adsorption ratios (3.7 to 21) were measured in discrete samples from the Powder River at Sussex, Wyoming. Median concentrations of sodium and sodium-adsorption ratios were substantially smaller in Crazy Woman Creek and Clear Creek, which tend to decrease sodium concentrations and sodium-adsorption ratios at the Powder River at Moorhead, Montana. Dissolved-solids concentrations in discrete samples were closely correlated with specific conductance values; Pearson's correlation coefficients were 0.98 or greater for all four sites. Regression equations for discrete values of specific conductance and sodium-adsorption ratios were statistically significant (p-values <0.001) at all four sites. The strongest relation (R2=0.92) was at the Powder River at Sussex, Wyoming. Relations on Crazy Woman Creek (R2=0.91) and Clear Creek (R2=0.83) also were strong. The relation between specific conductance and sodium-adsorption ratios was weakest (R2=0.65) at the Powder River at Moorhead, Montana; however, the relation was still significant. These data indicate that values of specific conductance are useful for estimating sodium-adsorption ratios. A regression model called LOADEST was used to estimate dissolved-solids loads for the four sites. The average daily mean dissolved-solids loads varied among the sites during water year 2004. The largest average daily mean dissolved-solids load was calculated for the Powder River at Moorhead, Montana. Although the smallest concentrations of dissolved solids were in samples from Clear Creek, the smallest average daily mean dissolved-solids load was calculated for Crazy Woman Creek. The largest loads occurred during spring runoff, and the smallest loads occurred in late summer, when streamflows typically were smallest. Dissolved-solids loads may be smaller than average during water years 2001-2004 because of smaller than average streamflow as a result of drought conditions.

Effect of Fresh Orange Juice Intake on Physiological Characteristics in Healthy Volunteers

PubMed Central

Asgary, Sedigheh; Keshvari, Mahtab; Afshani, Mohammad Reza; Javanmard, Shaghayegh Haghjooy

2014-01-01

Background. Impaired endothelial function is a predictor of cardiovascular events. Orange juice (OJ) is rich in dietary flavonoids and could inhibit oxidative stress and inflammatory responses. We examined the effects of commercial (COJ) and fresh orange juice (FOJ) on endothelial function and physiological characteristics in healthy humans. Materials and Methods. Twenty-two healthy volunteers years were enrolled in a single blind randomized crossover controlled trial. The two groups consumed either COJ for the first 4 weeks and then FOJ (CFOJ, 4 weeks), or FOJ for the first 4 weeks and then COJ (FCOJ, 4 weeks). We assessed endothelial function by measuring flow-mediated dilation, serum concentrations of lipids, apolipoproteins A and B (apo A-1 and apo B), and inflammatory markers such as vascular endothelial adhesion molecule 1 (VCAM-1), E-selectin, high-sensitivity C-reactive protein (hs-CRP), and interleukin-6. Results. Consumption of both juices decreased VCAM, hs-CRP, and E-selectin but increased apo A-1. A decline in LDL occurred in the FOJ group. There were no differences between the characteristics of two groups, with the exception of apo A-1 levels that were increased with both forms of OJ. The largest variations occurred with hs-CRP, VCAM in both groups. Conclusion. Consumption of COJ and FOJ produced beneficial effects on the physiological characteristics of healthy volunteers. Although these results could encourage the consumption of OJ, intervention studies are needed to determine the long-term effects of these types of OJ on metabolic and cardiovascular endpoints. PMID:24967267

Characteristics of electron distributions observed during large amplitude whistler wave events in the magnetosphere

NASA Astrophysics Data System (ADS)

Wilson, L. B., III; Cattell, C. A.; Kellogg, P. J.; Goetz, K.; Wygant, J.; Breneman, A. W.; Kersten, K.

2010-12-01

We present a statistical study of the characteristics of electron distributions associated with large amplitude whistler waves inside the terrestrial magnetosphere using waveform capture data as an addition of the study by Kellogg et al., [2010b]. We identified three types of electron distributions observed simultaneously with the whistler waves including beam-like, beam/flattop, and anisotropic distributions. The whistlers exhibited different characteristics dependent upon the observed electron distributions. The majority of the waveforms observed in our study have f/fce ≤ 0.5 and are observed primarily in the radiation belts outside the plasmapause simultaneously with anisotropic electron distributions. We also present an example waveform capture of the largest magnetic field amplitude (≥ 8 nT pk-pk) whistler wave measured in the radiation belts. The majority of the largest amplitude whistlers occur during magnetically active periods (AE > 200 nT).

Rates of speciation and morphological evolution are correlated across the largest vertebrate radiation.

PubMed

Rabosky, Daniel L; Santini, Francesco; Eastman, Jonathan; Smith, Stephen A; Sidlauskas, Brian; Chang, Jonathan; Alfaro, Michael E

2013-01-01

Several evolutionary theories predict that rates of morphological change should be positively associated with the rate at which new species arise. For example, the theory of punctuated equilibrium proposes that phenotypic change typically occurs in rapid bursts associated with speciation events. However, recent phylogenetic studies have found little evidence linking these processes in nature. Here we demonstrate that rates of species diversification are highly correlated with the rate of body size evolution across the 30,000+ living species of ray-finned fishes that comprise the majority of vertebrate biological diversity. This coupling is a general feature of fish evolution and transcends vast differences in ecology and body-plan organization. Our results may reflect a widespread speciational mode of character change in living fishes. Alternatively, these findings are consistent with the hypothesis that phenotypic 'evolvability'-the capacity of organisms to evolve-shapes the dynamics of speciation through time at the largest phylogenetic scales.

User's Guide for Monthly Vector Wind Profile Model

NASA Technical Reports Server (NTRS)

Adelfang, S. I.

1999-01-01

The background, theoretical concepts, and methodology for construction of vector wind profiles based on a statistical model are presented. The derived monthly vector wind profiles are to be applied by the launch vehicle design community for establishing realistic estimates of critical vehicle design parameter dispersions related to wind profile dispersions. During initial studies a number of months are used to establish the model profiles that produce the largest monthly dispersions of ascent vehicle aerodynamic load indicators. The largest monthly dispersions for wind, which occur during the winter high-wind months, are used for establishing the design reference dispersions for the aerodynamic load indicators. This document includes a description of the computational process for the vector wind model including specification of input data, parameter settings, and output data formats. Sample output data listings are provided to aid the user in the verification of test output.

On Examining the Transport and Transformation of Dissolved Organic Matter in The Albemarle-Pamlico Estuarine System, NC USA

NASA Astrophysics Data System (ADS)

Miller, R. L.; Buonassissi, C. J.; Brown, M. M.; Reed, R. E.

2016-02-01

The Albemarle-Pamlico Estuarine System (APES) in eastern North Carolina is the second largest estuary and largest lagoonal system in the United States. Variation in the amount of dissolved organic matter (DOM) delivered to the APES was examined for the Neuse and Tar/Pamlico River estuaries, two major components of the APES, using absorption spectra of Chromophoric Dissolved Organic Matter (CDOM). The quality of DOM and transformations that occur during down estuary transport were assessed using the spectral parameters SUVA254, SUVA350, S275-295, S350-400, and Sr calculated from CDOM spectra. We present results from several field campaigns that obtained surface samples during different stages of river discharge, including samples taken following Hurricane Irene (2011), and discuss the utility of using these newer optical indices of DOM quality for examining DOM dynamics in river dominated coastal waters.

Localized Rapid Warming of West Antarctic Subsurface Waters by Remote Winds

NASA Astrophysics Data System (ADS)

Griffies, S. M.; Spence, P.; Holmes, R.; Hogg, A. M.; Stewart, K. D.; England, M. H.

2017-12-01

The largest rates of Antarctic glacial ice mass loss are occurring tothe west of the Antarctica Peninsula in regions where warming ofsubsurface continental shelf waters is also largest. However, thephysical mechanisms responsible for this warming remain unknown. Herewe show how localized changes in coastal winds off East Antarctica canproduce significant subsurface temperature anomalies (>2C) around theentire continent. We demonstrate how coastal-trapped Kelvin wavescommunicate the wind disturbance around the Antarctic coastline. Thewarming is focused on the western flank of the Antarctic Peninsulabecause the anomalous circulation induced by the coastal-trapped wavesis intensified by the steep continental slope there, and because ofthe presence of pre-existing warm subsurface water. Thecoastal-trapped waves leads to an adjustment of the flow that shoalsisotherms and brings warm deep water upwards onto the continentalshelf and closer to the coast. This result demonstrates the uniquevulnerability of the West Antarctic region to a changing climate.

Characteristics of Electron Distributions Observed During Large Amplitude Whistler Wave Events in the Magnetosphere

NASA Technical Reports Server (NTRS)

Wilson, Lynn B., III

2010-01-01

We present a statistical study of the characteristics of electron distributions associated with large amplitude whistler waves inside the terrestrial magnetosphere using waveform capture data as an addition of the study by Kellogg et al., [2010b]. We identified three types of electron distributions observed simultaneously with the whistler waves including beam-like, beam/flattop, and anisotropic distributions. The whistlers exhibited different characteristics dependent upon the observed electron distributions. The majority of the waveforms observed in our study have f/fce < or = 0.5 and are observed primarily in the radiation belts outside the plasmapause simultaneously with anisotropic electron distributions. We also present an example waveform capture of the largest magnetic field amplitude (> or = 8 nT pk-pk) whistler wave measured in the radiation belts. The majority of the largest amplitude whistlers occur during magnetically active periods (AE > 200 nT).

Rupture propagation behavior and the largest possible earthquake induced by fluid injection into deep reservoirs

NASA Astrophysics Data System (ADS)

Gischig, Valentin S.

2015-09-01

Earthquakes caused by fluid injection into deep underground reservoirs constitute an increasingly recognized risk to populations and infrastructure. Quantitative assessment of induced seismic hazard, however, requires estimating the maximum possible magnitude earthquake that may be induced during fluid injection. Here I seek constraints on an upper limit for the largest possible earthquake using source-physics simulations that consider rate-and-state friction and hydromechanical interaction along a straight homogeneous fault. Depending on the orientation of the pressurized fault in the ambient stress field, different rupture behaviors can occur: (1) uncontrolled rupture-front propagation beyond the pressure front or (2) rupture-front propagation arresting at the pressure front. In the first case, fault properties determine the earthquake magnitude, and the upper magnitude limit may be similar to natural earthquakes. In the second case, the maximum magnitude can be controlled by carefully designing and monitoring injection and thus restricting the pressurized fault area.

Inertio Gravity Waves in the Upper Mesosphere

NASA Technical Reports Server (NTRS)

Mayr, H. G.; Mengel, J. G.; Talaat, E. L.; Porter, H. S.; Chan, K. L.

2003-01-01

In the polar region of the upper mesosphere, horizontal wind oscillations have been observed with periods around 10 hours (Hernandez et al., 1992). Such waves are generated in our Numerical Spectral Model (NSM) and appear to be inertio gravity waves (IGW). Like the planetary waves (PW) in the model, the IGWs are generated by instabilities that arise in the mean zonal circulation. In addition to stationary waves for m = 0, eastward and westward propagating waves for m = 1 to 4 appear above 70 km that grow in magnitude up to about 110 km, having periods between 9 and 11 hours. The m = 1 westward propagating IGWs have the largest amplitudes, which can reach at the poles 30 m/s. Like PWs, the IGWs are intermittent but reveal systematic seasonal variations, with the largest amplitudes occurring generally in winter and spring. The IGWs propagate upward with a vertical wavelength of about 20 km.

Factors associated with buying and selling syringes among injection drug users in a setting of one of North America's largest syringe exchange programs.

PubMed

Kuyper, Laura M; Kerr, Thomas; Li, Kathy; Hogg, Robert S; Tyndall, Mark W; Montaner, Julio S G; Wood, Evan

2006-01-01

We performed analyses of syringe buying and syringe selling among Vancouver injection drug users, recruited from May 1996 and followed up between November 2002 and August 2003, in the context of one of North America's largest syringe exchange programs (SEPs). An interviewer-administered questionnaire, approximately 45 minutes in duration, was used to collect information regarding risk factors for HIV infection and sources of sterile syringes. Seventy participants (15%) reported syringe selling and 122 (26%) reported syringe buying. Syringe sellers were more likely to be female, reside in unstable housing, need help injecting, and have visited the SEP at least once weekly. Syringe buyers were more likely to need help injecting, have difficulty finding new syringes, have binged on drugs, and have visited the SEP at least once weekly. Syringe buying most frequently occurred when the SEP was closed.

Mineral deposits and metallogeny of Alaska

USGS Publications Warehouse

Goldfarb, Richard J.; Meighan, Corey J.; Meinert, Lawrence D.; Wilson, Frederic H.

2016-01-01

Alaska, the largest State within the United States, and mainly located north of latitude 60°, is an important part of the Circum-Arctic region. Alaska is a richly endowed region with a long and complex geologic history. The mining history is short by world standards but nevertheless there are a number of world-class deposits in Alaska, of which Red Dog and Pebble are among the largest of their respective types in the world. Alaska is a collection of geologic terranes or regions having distinct histories, most of which were tectonically assembled in the period from 400 million years to 50 million years ago (late Paleozoic through early Tertiary). They now occur as numerous fault-bounded blocks in the northernmost part of the North American Cordillera on the western margin of the Laurentian craton. These terranes are comprised of rocks ranging in age from Paleoproterozoic to Recent.

Effects of pathogen-specific clinical mastitis on probability of conception in Holstein dairy cows.

PubMed

Hertl, J A; Schukken, Y H; Welcome, F L; Tauer, L W; Gröhn, Y T

2014-11-01

The objective of this study was to estimate the effects of pathogen-specific clinical mastitis (CM), occurring in different weekly intervals before or after artificial insemination (AI), on the probability of conception in Holstein cows. Clinical mastitis occurring in weekly intervals from 6 wk before until 6 wk after AI was modeled. The first 4 AI in a cow's lactation were included. The following categories of pathogens were studied: Streptococcus spp. (comprising Streptococcus dysgalactiae, Streptococcus uberis, and other Streptococcus spp.); Staphylococcus aureus; coagulase-negative staphylococci (CNS); Escherichia coli; Klebsiella spp.; cases with CM signs but no bacterial growth (above the level that can be detected from our microbiological procedures) observed in the culture sample and cases with contamination (≥ 3 pathogens in the sample); and other pathogens [including Citrobacter, yeasts, Trueperella pyogenes, gram-negative bacilli (i.e., gram-negative organisms other than E. coli, Klebsiella spp., Enterobacter, and Citrobacter), Corynebacterium bovis, Corynebacterium spp., Pasteurella, Enterococcus, Pseudomonas, Mycoplasma, Prototheca, and others]. Other factors included in the model were parity (1, 2, 3, 4 and higher), season of AI (winter, spring, summer, autumn), day in lactation of first AI, farm, and other non-CM diseases (retained placenta, metritis, ketosis, displaced abomasum). Data from 90,271 AI in 39,361 lactations in 20,328 cows collected from 2003/2004 to 2011 from 5 New York State dairy farms were analyzed in a generalized linear mixed model with a Poisson distribution. The largest reductions in probability of conception were associated with CM occurring in the week before AI or in the 2 wk following AI. Escherichia coli and Klebsiella spp. had the greatest adverse effects on probability of conception. The probability of conception for a cow with any combination of characteristics may be calculated based on the parameter estimates. These findings may be helpful to farmers in assessing reproduction in their dairy cows for more effective cow management. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Multiscale spatial and small-scale temporal variation in the composition of Riverine fish communities.

PubMed

Growns, Ivor; Astles, Karen; Gehrke, Peter

2006-03-01

We studied the multiscale (sites, river reaches and rivers) and short-term temporal (monthly) variability in a freshwater fish assemblage. We found that small-scale spatial variation and short-term temporal variability significantly influenced fish community structure in the Macquarie and Namoi Rivers. However, larger scale spatial differences between rivers were the largest source of variation in the data. The interaction between temporal change and spatial variation in fish community structure, whilst statistically significant, was smaller than the variation between rivers. This suggests that although the fish communities within each river changed between sampling occasions, the underlying differences between rivers were maintained. In contrast, the strongest interaction between temporal and spatial effects occurred at the smallest spatial scale, at the level of individual sites. This means whilst the composition of the fish assemblage at a given site may fluctuate, the magnitude of these changes is unlikely to affect larger scale differences between reaches within rivers or between rivers. These results suggest that sampling at any time within a single season will be sufficient to show spatial differences that occur over large spatial scales, such as comparisons between rivers or between biogeographical regions.

Runaway cultural niche construction

PubMed Central

Rendell, Luke; Fogarty, Laurel; Laland, Kevin N.

2011-01-01

Cultural niche construction is a uniquely potent source of selection on human populations, and a major cause of recent human evolution. Previous theoretical analyses have not, however, explored the local effects of cultural niche construction. Here, we use spatially explicit coevolutionary models to investigate how cultural processes could drive selection on human genes by modifying local resources. We show that cultural learning, expressed in local niche construction, can trigger a process with dynamics that resemble runaway sexual selection. Under a broad range of conditions, cultural niche-constructing practices generate selection for gene-based traits and hitchhike to fixation through the build up of statistical associations between practice and trait. This process can occur even when the cultural practice is costly, or is subject to counteracting transmission biases, or the genetic trait is selected against. Under some conditions a secondary hitchhiking occurs, through which genetic variants that enhance the capability for cultural learning are also favoured by similar dynamics. We suggest that runaway cultural niche construction could have played an important role in human evolution, helping to explain why humans are simultaneously the species with the largest relative brain size, the most potent capacity for niche construction and the greatest reliance on culture. PMID:21320897

Modelling the Wake of the Marquesas Archipelago

NASA Astrophysics Data System (ADS)

Raapoto, H.; Martinez, E. C.; Petrenko, A. A.; Doglioli, A. M.; Maes, C.

2017-12-01

In this study, a high-resolution ( 2.5 km) numerical model was set up to investigate the fine-scale activity within the region of the Marquesas archipelago where a strong biological enhancement occurs. This has never been performed before. The robustness of the model results is assessed by comparison with remote sensing and in situ observations. Our results highlight regions of warm waters leeward of the different islands with high eddy kinetic energy (EKE) on their sides. The analysis of energy conversion terms reveals contributions to EKE variability by wind, baroclinic and barotropic instabilities. The use of a geometry-based eddy detection algorithm reveals eddy generation in the wake of the largest islands, with both an inshore and offshore effect. Maximum eddy activity occurs in austral winter following the seasonality of both wind stress and EKE intensity. Most eddies have a radius between 20 and 30 km and are generally cyclonic rather than anticyclonic. Significant vertical velocities are observed in the proximity of the islands, associated with topography induced flow separation. Eddy trapping inshore waters are advected offshore in the wake of the islands. The overall influence of these fine-scale dynamics could explain the strong biological enhancement of the archipelago.

Search for Magnetically Broadened Cascade Emission from Blazars with VERITAS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Archambault, S.; Griffin, S.; Archer, A.

2017-02-01

We present a search for magnetically broadened gamma-ray emission around active galactic nuclei (AGNs), using VERITAS observations of seven hard-spectrum blazars. A cascade process occurs when multi-TeV gamma-rays from an AGN interact with extragalactic background light (EBL) photons to produce electron–positron pairs, which then interact with cosmic microwave background photons via inverse-Compton scattering to produce gamma-rays. Due to the deflection of the electron–positron pairs, a non-zero intergalactic magnetic field (IGMF) would potentially produce detectable effects on the angular distribution of the cascade emission. In particular, an angular broadening compared to the unscattered emission could occur. Through non-detection of angularly broadenedmore » emission from 1ES 1218+304, the source with the largest predicted cascade fraction, we exclude a range of IGMF strengths around 10{sup −14} G at the 95% confidence level. The extent of the exclusion range varies with the assumptions made about the intrinsic spectrum of 1ES 1218+304 and the EBL model used in the simulation of the cascade process. All of the sources are used to set limits on the flux due to extended emission.« less

Telluric currents: A meeting of theory and observation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Boteler, D.H.; Seager, W.H.

Pipe-to-soil (P/S) potential variations resulting from telluric currents have been observed on pipelines in many locations. However, it has never teen clear which parts of a pipeline will experience the worst effects. Two studies were conducted to answer this question. Distributed-source transmission line (DSTL) theory was applied to the problem of modeling geomagnetic induction in pipelines. This theory predicted that the largest P/S potential variations would occur at the ends of the pipeline. The theory also predicted that large P/S potential variations, of opposite sign, should occur on either side of an insulating flange. Independently, an observation program was conductedmore » to determine the change in telluric current P/S potential variations and to design counteractive measures along a pipeline in northern Canada. Observations showed that the amplitude of P/S potential fluctuations had maxima at the northern and southern ends of the pipeline. A further set of recordings around an insulating flange showed large P/S potential variations, of opposite sign, on either side of the flange. Agreement between the observations and theoretical predictions was remarkable. While the observations confirmed the theory, the theory explains how P/S potential variations are produced by telluric currents and provides the basis for design of cathodic protection systems for pipelines that can counteract any adverse telluric effects.« less

The Endemicity of Human Fascioliasis in Guilan Province, Northern Iran: the Baseline for Implementation of Control Strategies

PubMed Central

ASHRAFI, Keyhan; SAADAT, Farshid; O’NEILL, Sandra; RAHMATI, Behnaz; AMIN TAHMASBI, Hadid; PIUS DALTON, John; NADIM, Abolhassan; ASADINEZHAD, Mohsen; REZVANI, Sayed Mahmood

2015-01-01

Background: The largest global outbreaks of liver fluke disease (Fascioliasis) in humans, caused by species of the genus Fasciola, have occurred in Guilan Province of Iran, affecting more than 15000 people. Although, different aspects of fascioliasis have been the subject of various researches during last two decades, nevertheless no community-based study has been performed in endemic regions of Guilan. The aim of present study was to obtain the basic information needed to develop future control strategies. Methods: Fecal and blood samples were collected from 1,984 volunteers in the Bandar-Anzali district, the region where previous epidemics occurred. Fecal samples were examined by Kato-Katz and formalin-ether methods for the presence of Fasciola eggs. Sera samples were analyzed by ELISA to detect anti-cathepsin L antibodies. Results: Twenty-seven (1.36%) individuals were seropositive, 9 (0.45%) individuals were egg positive (mean egg count 50.7 (±30.36) eggs per gram of faeces) and 30 individuals (1.51%) were positive using both methods. No statistical association was observed between infection and age, gender, location, occupation, educational status and dietary habits. The prevalence of intestinal parasites is also included. Conclusion: Human fascioliasis is hypoendemic in this region and recommends a passive case-finding approach, effective primary prevention measures, health education through mass media and effective veterinary public health measures for control of human disease. PMID:26056669

Two-faced property of a market factor in asset pricing and diversification effect

NASA Astrophysics Data System (ADS)

Eom, Cheoljun

2017-04-01

This study empirically investigates the test hypothesis that a market factor acting as a representative common factor in the pricing models has a negative influence on constructing a well-diversified portfolio from the Markowitz mean-variance optimization function (MVOF). We use the comparative correlation matrix (C-CM) method to control a single eigenvalue among all eigenvalues included in the sample correlation matrix (S-CM), through the random matrix theory (RMT). In particular, this study observes the effect of the largest eigenvalue that has the property of the market factor. According to the results, the largest eigenvalue has the highest explanatory power on the stock return changes. The C-CM without the largest eigenvalue in the S-CM constructs a more diversified portfolio capable of improving the practical applicability of the MVOF. Moreover, the more diversified portfolio constructed from this C-CM has better out-of-sample performance in the future period. These results support the test hypothesis for the two-faced property of the market factor, defined by the largest eigenvalue.

Prevalence and Functioning of Children with Cerebral Palsy in Four Areas of the United States in 2006: A Report from the Autism and Developmental Disabilities Monitoring Network

ERIC Educational Resources Information Center

Kirby, Russell S.; Wingate, Martha S.; Van Naarden Braun, Kim; Doernberg, Nancy S.; Arneson, Carrie L.; Benedict, Ruth E.; Mulvihill, Beverly; Durkin, Maureen S.; Fitzgerald, Robert T.; Maenner, Matthew J.; Patz, Jean A.; Yeargin-Allsopp, Marshalyn

2011-01-01

Aim: To estimate the prevalence of cerebral palsy (CP) and the frequency of co-occurring developmental disabilities (DDs), gross motor function (GMF), and walking ability using the largest surveillance DD database in the US. Methods: We conducted population-based surveillance of 8-year-old children in 2006 (N = 142,338), in areas of Alabama,…

An overview of University of Alaska Anchorage, ENRI research on the spruce bark beetle infestation, Kenai Peninsula, Alaska, 1997-2002

Treesearch

Vernon J. LaBau

2006-01-01

In the mid 1990s, one of the largest bark beetle infestations seen anywhere in the world occurred on the Kenai Peninsula of Alaska. In one year, the infestation affected over one million acres of spruce in Alaska. This paper presents a coalescence of several aspects of study on the problem, including tree inventory and mortality, regeneration, understory response, a...

An ecological assessment of land use impacts in small watersheds of the Chesapeake Bay

Treesearch

Andrew Leight; John Jacobs; Lonnie Gonsalves; Gretchen Messick; Shawn McLaughlin; Jay Lewis; Juliana Brush; Eric Daniels; Matthew Rhodes; Lewis Collier; Robert Wood

2016-01-01

The Chesapeake Bay, the nation’s largest estuary, remains in relatively poor condition despite intensive public and scientific attention. In order to better understand the stressors and impacts occurring in the Bay as a result of land management decisions we conducted an assessment of both habitat condition and organismal response in three small watersheds of the upper...

The Paracel Islands and U.S. Interests and Approaches in the South China Sea

DTIC Science & Technology

2014-06-01

Billiton, and Hong Kong-owned and Canada-based Husky Energy. Initial Chinese offshore exploitation occurred in the nearby Pearl River Mouth Basin and...possibility for marine-based tourism in the region, and in April 2013, China authorized tourists to visit the Paracels.40 China, which currently controls...the entire Paracel archipelago, is expanding tourism , fishing, and the military garrison on Woody Island, the archipelago’s largest feature, as the

Great Barrier Reef, Queensland, Australia

NASA Technical Reports Server (NTRS)

1990-01-01

This detailed view of the Great Barrier Reef, Queensland, Australia (19.5S, 149.5E) shows several small patch reefs within the overall reef system. The Great Barrier Reef, largest in the world, comprises thousands of individual reefs of great variety and are closely monitored by marine ecologists. These reefs are about 6000 years old and sit on top of much older reefs. The most rapid coral growth occurs on the landward side of the reefs.

Effect of preservatives on the accuracy of mid-infrared milk component testing.

PubMed

Barbano, D M; Wojciechowski, K L; Lynch, J M

2010-12-01

Our objective was to determine the effect of commonly used milk preservatives on the accuracy of fat, protein, and lactose content determination in milk by mid-infrared (mid-IR) milk analysis. Two producer raw milks (Holstein and Jersey) and 2 pasteurized modified milks, 1 similar to Holstein milk and 1 similar to Jersey milk were used as the 4 different milk sources. Seven different milk preservative approaches (K(2)Cr(2)O(7) and 6 different bronopol-based preservatives) and a portion of unpreserved milk for each of the 4 different milks sources were tested for fat B, lactose, protein, and fat A. The experiment was replicated 3 times (28 d each) for a total of 84 d. Two mid-infrared (mid-IR) transmittance milk analyzers (an optical and a virtual filter instrument) were used. A large batch of pilot milk was prepared from pasteurized, homogenized, unpreserved whole milk, split into vials, quick frozen by immersion in liquid nitrogen, and transferred into a -80 °C freezer. Pilots were thawed and analyzed on each testing day during the study. Significant increases were observed in all uncorrected readings on the pilot milks over the 84 d of the study, but the increases were gradual and small on each instrument for all components. Results from the study were corrected for these changes. A significant difference in mid-IR fat A readings was observed, whereas no differences were detected for fat B, lactose, or protein between unpreserved and preserved milks containing 0.02% K(2)Cr(2)O(7.) Therefore, K(2)Cr(2)O(7) has little or no effect on mid-IR test results. All bronopol-based preservative approaches in this study differed in mid-IR test results compared with K(2)Cr(2)O(7)-preserved and unpreserved milks, with the largest effect on protein results. Mid-IR uncorrected readings increased with time of refrigerated storage at 4°C for all preservative approaches, with the largest increase for protein. The rate of increase in uncorrected readings with time of storage was always higher for raw milks than for pasteurized milks, and the stability of instrument zero was lower for raw milks than for pasteurized milks. The largest economic effect of a systematic bias caused by a preservative occurs when the milks used for calibration and routine testing for payment do not contain the same preservative or when calibration milks are preserved and milks for routine testing are unpreserved. These effects can create errors in payment for large dairy processing plants ranging from several hundred thousand to over a million dollars annually. Copyright © 2010 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

The 2013–2016 induced earthquakes in Harper and Sumner Counties, southern Kansas

USGS Publications Warehouse

Rubinstein, Justin L.; Ellsworth, William L.; Dougherty, Sara L.

2018-01-01

We examine the first four years (2013–2016) of the ongoing seismicity in southern Kansas using high‐precision locations derived from a local seismometer network. The earthquakes occur almost exclusively in the shallow crystalline basement, below the wastewater injection horizon of the Arbuckle Group at the base of the sedimentary section. Multiple lines of evidence lead us to conclude that disposal of wastewater from the production of oil and gas by deep injection is the probable cause for the surge of seismicity that began in 2013. First, the seismicity correlates in space and time with the injection. We observe increases in seismicity subsequent to increases in injection and decreases in seismicity in response to decreases in injection. Second, the earthquake‐rate change is statistically improbable to be of natural origin. From 1974 through the time of the injection increase in 2012, no ML">ML 4 or larger earthquakes occurred in the study area, while six occurred between 2012 and 2016. The probability of this rate change occurring randomly is ∼0.16%">∼0.16%. Third, the other potential industrial drivers of seismicity (hydraulic fracturing and oil production) do not correlate in space or time with seismicity. Local geological conditions are important in determining whether injection operations will induce seismicity, as shown by absence of seismicity near the largest injection operations in the southwest portion of our study area. In addition to local operations, the presence of seismicity 10+ km from large injection wells indicates that regional injection operations also need to be considered to understand the effects of injection on seismicity.

Assessment of the Contribution of Poultry and Pig Production to Greenhouse Gas Emissions in South Korea Over the Last 10 Years (2005 through 2014).

PubMed

Boontiam, Waewaree; Shin, Yongjin; Choi, Hong Lim; Kumari, Priyanka

2016-12-01

The goal of this study was to estimate the emissions of greenhouse gases (GHG), namely methane (CH 4 ), nitrous oxide (N 2 O), and carbon dioxide (CO 2 ) from poultry and pig production in South Korea over the last 10 years (2005 through 2014). The calculations of GHG emissions were based on Intergovernmental Panel on Climate Change (IPCC) guidelines. Over the study period, the CH 4 emission from manure management decreased in layer chickens, nursery to finishing pigs and gestating to lactating sows, but there was a gradual increase in CH 4 emission from broiler chickens and male breeding pigs. Both sows and nursery to finishing pigs were associated with greater emissions from enteric fermentation than the boars, especially in 2009. Layer chickens produced lower direct and indirect N 2 O emissions from 2009 to 2014, whereas the average direct and indirect N 2 O emissions from manure management for broiler chickens were 12.48 and 4.93 Gg CO 2 -eq/yr, respectively. Annual direct and indirect N 2 O emissions for broiler chickens tended to decrease in 2014. Average CO 2 emission from direct on-farm energy uses for broiler and layer chickens were 46.62 and 136.56 Gg CO 2 -eq/yr, respectively. For pig sectors, the N 2 O emission from direct and indirect sources gradually increased, but they decreased for breeding pigs. Carbon dioxide emission from direct on-farm energy uses reached a maximum of 53.93 Gg CO 2 -eq/yr in 2009, but this total gradually declined in 2010 and 2011. For boars, the greatest CO 2 emission occurred in 2012 and was 9.44 Gg CO 2 -eq/yr. Indirect N 2 O emission was the largest component of GHG emissions in broilers. In layer chickens, the largest contributing factor to GHG emissions was CO 2 from direct on-farm energy uses. For pig production, the largest component of GHG emissions was CH 4 from manure management, followed by CO 2 emission from direct on-farm energy use and CH 4 enteric fermentation emission, which accounted for 8.47, 2.85, and 2.82 Gg-CO 2 /yr, respectively. The greatest GHG emission intensity occurred in female breeding sows relative to boars. Overall, it is an important issue for the poultry and pig industry of South Korea to reduce GHG emissions with the effective approaches for the sustainability of agricultural practices.

Assessment of the Contribution of Poultry and Pig Production to Greenhouse Gas Emissions in South Korea Over the Last 10 Years (2005 through 2014)

PubMed Central

Boontiam, Waewaree; Shin, Yongjin; Choi, Hong Lim; Kumari, Priyanka

2016-01-01

The goal of this study was to estimate the emissions of greenhouse gases (GHG), namely methane (CH4), nitrous oxide (N2O), and carbon dioxide (CO2) from poultry and pig production in South Korea over the last 10 years (2005 through 2014). The calculations of GHG emissions were based on Intergovernmental Panel on Climate Change (IPCC) guidelines. Over the study period, the CH4 emission from manure management decreased in layer chickens, nursery to finishing pigs and gestating to lactating sows, but there was a gradual increase in CH4 emission from broiler chickens and male breeding pigs. Both sows and nursery to finishing pigs were associated with greater emissions from enteric fermentation than the boars, especially in 2009. Layer chickens produced lower direct and indirect N2O emissions from 2009 to 2014, whereas the average direct and indirect N2O emissions from manure management for broiler chickens were 12.48 and 4.93 Gg CO2-eq/yr, respectively. Annual direct and indirect N2O emissions for broiler chickens tended to decrease in 2014. Average CO2 emission from direct on-farm energy uses for broiler and layer chickens were 46.62 and 136.56 Gg CO2-eq/yr, respectively. For pig sectors, the N2O emission from direct and indirect sources gradually increased, but they decreased for breeding pigs. Carbon dioxide emission from direct on-farm energy uses reached a maximum of 53.93 Gg CO2-eq/yr in 2009, but this total gradually declined in 2010 and 2011. For boars, the greatest CO2 emission occurred in 2012 and was 9.44 Gg CO2-eq/yr. Indirect N2O emission was the largest component of GHG emissions in broilers. In layer chickens, the largest contributing factor to GHG emissions was CO2 from direct on-farm energy uses. For pig production, the largest component of GHG emissions was CH4 from manure management, followed by CO2 emission from direct on-farm energy use and CH4 enteric fermentation emission, which accounted for 8.47, 2.85, and 2.82 Gg-CO2/yr, respectively. The greatest GHG emission intensity occurred in female breeding sows relative to boars. Overall, it is an important issue for the poultry and pig industry of South Korea to reduce GHG emissions with the effective approaches for the sustainability of agricultural practices. PMID:26954125

Association of monthly frequencies of diverse diseases in the calls to the public emergency service of the city of Buenos Aires during 1999-2004 with meteorological variables and seasons.

PubMed

Alexander, P

2013-01-01

This work aims to study associations between monthly averages of meteorological variables and monthly frequencies of diverse diseases in the calls to the public ambulance emergency service of the city of Buenos Aires during the years 1999-2004. Throughout this time period no changes were made in the classification codes of the illnesses. Heart disease, arrhythmia, heart failure, cardiopulmonary arrest, angina pectoris, psychiatric diseases, stroke, transient ischemic attack, syncope and the total number of calls were analyzed against 11 weather variables and the four seasons. All illnesses exhibited some seasonal behavior, except cardiorespiratory arrest and angina pectoris. The largest frequencies of illnesses that exhibited some association with the meteorological variables used to occur in winter, except the psychiatric cases. Heart failure, stroke, psychiatric diseases and the total number of calls showed significant correlations with the 11 meteorological variables considered, and the largest indices (absolute values above 0.6) were found for the former two pathologies. On the other side, cardiorespiratory arrest and angina pectoris revealed no significant correlations and nearly null indices. Variables associated with temperature were the meteorological proxies with the largest correlations against diseases. Pressure and humidity mostly exhibited positive correlations, which is the opposite of variables related to temperature. Contrary to all other diseases, psychiatric pathologies showed a clear predominance of positive correlations. Finally, the association degree of the medical dataset with recurrent patterns was further evaluated through Fourier analysis, to assess the presence of statistically significant behavior. In the Northern Hemisphere high morbidity and mortality rates in December are usually assigned to diverse factors in relation to the holidays, but such an effect is not observed in the present analysis. There seems to be no clearly preferred meteorological proxy among the different types of temperatures used. It is shown that the amount of occurrences depends mainly on season rather on its strength quantified by temperature.

Association of monthly frequencies of diverse diseases in the calls to the public emergency service of the city of Buenos Aires during 1999-2004 with meteorological variables and seasons

NASA Astrophysics Data System (ADS)

Alexander, P.

2013-01-01

This work aims to study associations between monthly averages of meteorological variables and monthly frequencies of diverse diseases in the calls to the public ambulance emergency service of the city of Buenos Aires during the years 1999-2004. Throughout this time period no changes were made in the classification codes of the illnesses. Heart disease, arrhythmia, heart failure, cardiopulmonary arrest, angina pectoris, psychiatric diseases, stroke, transient ischemic attack, syncope and the total number of calls were analyzed against 11 weather variables and the four seasons. All illnesses exhibited some seasonal behavior, except cardiorespiratory arrest and angina pectoris. The largest frequencies of illnesses that exhibited some association with the meteorological variables used to occur in winter, except the psychiatric cases. Heart failure, stroke, psychiatric diseases and the total number of calls showed significant correlations with the 11 meteorological variables considered, and the largest indices (absolute values above 0.6) were found for the former two pathologies. On the other side, cardiorespiratory arrest and angina pectoris revealed no significant correlations and nearly null indices. Variables associated with temperature were the meteorological proxies with the largest correlations against diseases. Pressure and humidity mostly exhibited positive correlations, which is the opposite of variables related to temperature. Contrary to all other diseases, psychiatric pathologies showed a clear predominance of positive correlations. Finally, the association degree of the medical dataset with recurrent patterns was further evaluated through Fourier analysis, to assess the presence of statistically significant behavior. In the Northern Hemisphere high morbidity and mortality rates in December are usually assigned to diverse factors in relation to the holidays, but such an effect is not observed in the present analysis. There seems to be no clearly preferred meteorological proxy among the different types of temperatures used. It is shown that the amount of occurrences depends mainly on season rather on its strength quantified by temperature.

Seafloor seismological/geodetic observations in the rupture area of the 2011 Tohoku-oki Earthquake

NASA Astrophysics Data System (ADS)

Hino, Ryota; Shinohara, Masanao; Ito, Yoshihiro

2016-04-01

A number of important aspects of the 2011 Tohoku-oki earthquake (Mw 9.0) were clarified by the seafloor seismological and geodetic observation above the rupture area of the earthquake. Besides the extraordinarily large coseismic displacements, various kinds of slow slip phenomena associated with intensive micro-seismicity on the plate boundary fault were identified by near field ocean bottom seismographs and seafloor geodetic observation networks. The Tohoku-oki earthquake was preceded by evident foreshock activity with a spatial expansion of this seismicity. The activity became significantly intense after the occurrence of the largest foreshock two days before the mainshock rupture. During the period, clear continuous seafloor deformation was identified caused by the aseismic slip following the largest foreshock. Another different type of aseismic slip event had occurred before this pre-imminent activity had started about a month before the largest foreshock happened. The observed increased seismicity associated with aseismic slip suggests that there must have been some chain reaction like interplay of seismic and interseismic slips before the large earthquake broke out. However, no evident deformation signals were observed indicating acceleration of fault slip immediately before the mainshock. Seafloor geodetic measurements reveals that the postseismic deformation around the rupture area of the Tohoku-oki earthquake shows complex spatial pattern and the complexity is mostly due to significant viscoelastic relaxation induced by the huge coseismic slip. The effects of viscoelastic deformation makes it difficult to identify the deformation associated with the after slip or regaining of interplate coupling and requires us to enhance the abilities of seafloor monitoring to detect the slip activities on the fault. We started an array of seismometer arrays observation including broad-band seismographs to detect and locate slow-slip events and low-frequency tremors. Another observation we started is direct-path acoustic ranging across the trench axis. Slip rate of the shallow fault can be measured by monitoring the change in distance between the benchmarks on the incoming and overrding plates.

Assessment of soil and water contaminants from selected locations in and near the Idaho Army National Guard Orchard Training Area, Ada County, Idaho, 2001-2003

USGS Publications Warehouse

Parliman, D.J.

2004-01-01

In 2001, the National Guard Bureau and the U.S. Geological Survey began a project to compile hydrogeologic data and determine presence or absence of soil, surface-water, and ground-water contamination at the Idaho Army National Guard Orchard Training Area in southwestern Idaho. Between June 2002 and April 2003, a total of 114 soil, surface-water, ground-water, precipitation, or dust samples were collected from 68 sample sites (65 different locations) in the Orchard Training Area (OTA) or along the vehicle corridor to the OTA. Soil and water samples were analyzed for concentrations of selected total trace metals, major ions, nutrients, explosive compounds, semivolatile organics, and petroleum hydrocarbons. Water samples also were analyzed for concentrations of selected dissolved trace metals and major ions. Distinguishing naturally occurring large concentrations of trace metals, major ions, and nutrients from contamination related to land and water uses at the OTA was difficult. There were no historical analyses for this area to compare with modern data, and although samples were collected from 65 locations in and near the OTA, sampled areas represented only a small part of the complex OTA land-use areas and soil types. For naturally occurring compounds, several assumptions were made?anomalously large concentrations, when tied to known land uses, may indicate presence of contamination; naturally occurring concentrations cannot be separated from contamination concentrations in mid- and lower ranges of data; and smallest concentrations may represent the lowest naturally occurring range of concentrations and (or) the absence of contaminants related to land and water uses. Presence of explosive, semivolatile organic (SVOC), and petroleum hydrocarbon compounds in samples indicates contamination from land and water uses. In areas along the vehicle corridor and major access roads within the OTA, most trace metal, major ion, and nutrient concentrations in soil samples were not in the upper 10th percentile of data, but concentrations of 25 metals, ions, or nutrients were in the upper 10th percentile in a puddle sample near the heavy equipment maneuvering area, MPRC-H. The largest concentrations of tin, ammonia, and nitrite plus nitrate (as nitrogen) in water from the OTA were detected in a sample from this puddle. Petroleum hydrocarbons were the most common contaminant, detected in all soil and surface-water samples. An SVOC, bis (2-ethylhexyl) phthalate, a plasticizer, was detected at a site along the vehicle corridor. In Maneuver Areas within the OTA, many soil samples contained at least one trace metal, major ion, or nutrient in the upper 10th percentile of data, and the largest concentrations of cobalt, iron, mercury, titanium, sodium, ammonia, or total phosphorus were detected in 6 of 13 soil samples outside the Tadpole Lake area. The largest concentrations of aluminum, arsenic, beryllium, nickel, selenium, silver, strontium, thallium, vanadium, chloride, potassium, sulfate, and nitrite plus nitrate were detected in soil samples from the Tadpole Lake area. Water from Tadpole Lake contained the largest total concentrations of 19 trace metals, 4 major ions, and 1 nutrient. Petroleum hydrocarbons were detected in 5 soil samples and water from Tadpole Lake. SVOCs related to combustion of fuel or plasticizers were detected in 1 soil sample. Explosive compounds were detected in 1 precipitation sample.In the Impact Area within the OTA, most soil samples contained at least one trace metal, major ion, or nutrient in the upper 10th percentile of data, and the largest concentrations of barium, chromium, copper, manganese, lead, or orthophosphate were detected in 6 of the 18 soil samples. Petroleum hydrocarbons were detected in 4 soil samples, SVOCs in 6 samples, and explosive compounds in 4 samples. In the mobilization and training equipment site (MATES) compound adjacent to the OTA, all soil and water samples contained at lea

Triennial Growth Symposium: effects of polymeric carbohydrates on growth and development in pigs.

PubMed

Bach Knudsen, K E

2011-07-01

Polymeric carbohydrates, starch and nonstarch polysaccharides (NSP), quantitatively represent the largest portion of the diets for pigs and are, therefore, the largest energy contributor. The 2 types of polysaccharides, however, have different fates and functions in the gastrointestinal tract and lead to different metabolites upon digestion. Pancreatic and mucosal enzymes in the small intestine break down the majority of starch, whereas NSP primarily are degraded by the microflora in the large intestine. Starch degradation leads to the release of glucose, which is absorbed by an active absorption process that triggers the release of insulin from the pancreas, whereas the fermentation of NSP to short-chain fatty acids (SCFA; i.e., acetate, propionate, and butyrate) occurs at a slower and more constant rate and with SCFA being absorbed by passive diffusion. Type and amounts of polymeric carbohydrates influence growth and development through different mechanisms. First, the proportion of starch to NSP plays an important role for the content of available energy (i.e., DE, ME, and NE); available energy relative to protein is crucial for performance and carcass quality. Second, the proportion of starch to NSP will influence rate and type of metabolites (i.e., glucose vs. SCFA) deriving from carbohydrate assimilation. Third and finally, the type of starch (i.e., types A, B, and C) and soluble NSP will influence the release of insulin, the hormone that facilitates nutrient uptake by tissues, organs, and cells, and thus plays a critically essential role in protein synthesis and muscle growth, as well as lipid synthesis and adipose tissue growth. In conclusion, polymeric carbohydrates influence growth and development through events in the gut and direct and indirect effects of different metabolites deriving from carbohydrate assimilation. © 2011 American Society of Animal Science. All rights reserved.

Relationship characteristics and sexual risk-taking in young men who have sex with men.

PubMed

Mustanski, Brian; Newcomb, Michael E; Clerkin, Elise M

2011-09-01

Young men who have sex with men (MSM), particularly young men of color, are experiencing the largest increase in HIV incidence of any risk group in the United States Epidemiological research suggests that the majority of transmissions among MSM are occurring in the context of primary partnerships, but little research has been done on the processes within these dyads that increase HIV risk behaviors. The aim of this study was to use longitudinal partnership-level data to explore the effects of partner and relationship characteristics on the frequency of unprotected sex within young MSM relationships. One hundred twenty-two young MSM (age 16-20 at baseline) were assessed at three time-points six months apart, with 91% retention at the 12-month follow-up wave. Over 80% were racial/ethnic minorities. At each wave, participants reported on characteristics of the relationships and partners for up to three sexual partners. Hierarchical linear modeling was used for analyses. The largest effect was for considering the relationship to be serious, which was associated with nearly an eightfold increase in the rate of unprotected sex. Other factors that increased risk behaviors included older partners, drug use prior to sex, physical violence, forced sex, and partnership lasting more than six months. Partners met online were not associated with significantly more sexual risk. These data provide insight into the relationship processes that should be addressed in prevention programs targeted at young MSM. Relationships may serve as a promising unit for HIV prevention interventions, although more formative research will be required to address potential logistical obstacles to implementing such interventions. The partner-by-partner analytic approach (i.e., evaluating situational variables associated with several partners for a given participant) holds promise for future HIV behavioral research.

Relationship characteristics and sexual risk-taking in young men who have sex with men

PubMed Central

Mustanski, Brian; Newcomb, Michael E.; Clerkin, Elise M.

2011-01-01

Objective Young MSM (men who have sex with men), particularly young men of color, are experiencing the largest increase in HIV incidence of any risk group in the U.S. Epidemiological research suggests that the majority of transmissions among MSM are occurring in the context of primary partnerships, but little research has been done on the processes within these dyads that increase HIV risk behaviors. The aim of this study was to use longitudinal partnership-level data to explore the effects of partner and relationship characteristics on the frequency of unprotected sex within young MSM relationships. Methods One hundred twenty-two young MSM (age 16-20 at baseline) were assessed at three time-points six months apart, with 91% retention at the 12-month follow-up wave. Over 80% were racial/ethnic minorities. At each wave, participants reported on characteristics of the relationship and partner for up to three sexual partners. Hierarchical linear modeling was used for analyses. Results The largest effect was for considering the relationship to be serious, which was associated with nearly an eight-fold increase in the rate of unprotected sex. Other factors that increased risk behaviors included: older partners, drug use prior to sex, physical violence, forced sex, and partnership lasting more than 6 months. Partners met online were not associated with significantly more sexual risk. Conclusions These data provide insight into the relationship processes that should be addressed in prevention programs targeted at young MSM. Relationships may serve as a promising unit for HIV prevention interventions, although more formative research will be required to address potential logistical obstacles to implementing such interventions. The partner-by-partner analytic approach (i.e., evaluating situational variables associated with several partners for a given participant) holds promise for future HIV behavioral research. PMID:21604883

Acute Alcohol Intoxication Decreases Glucose Metabolism but Increases Acetate Uptake in the Human Brain

PubMed Central

Volkow, Nora D.; Kim, Sung Won; Wang, Gene-Jack; Alexoff, David; Logan, Jean; Muench, Lisa; Shea, Colleen; Telang, Frank; Fowler, Joanna S.; Wong, Christopher; Benveniste, Helene; Tomasi, Dardo

2012-01-01

Alcohol intoxication results in marked reductions in brain glucose metabolism, which we hypothesized reflect not just its GABAergic enhancing effects but also metabolism of acetate as an alternative brain energy source. To test this hypothesis we separately assessed the effects of alcohol intoxication on brain glucose and acetate metabolism using Positron Emission Tomography (PET). We found that alcohol intoxication significantly decreased whole brain glucose metabolism (measured with FDG) with the largest decrements in cerebellum and occipital cortex and the smallest in thalamus. In contrast, alcohol intoxication caused a significant increase in [1-11C]acetate brain uptake (measured as standard uptake value, SUV), with the largest increases occurring in cerebellum and the smallest in thalamus. In heavy alcohol drinkers [1-11C]acetate brain uptake during alcohol challenge trended to be higher than in occasional drinkers (p <0.06) and the increases in [1-11C]acetate uptake in cerebellum with alcohol were positively associated with the reported amount of alcohol consumed (r=0.66, p<0.01). Our findings corroborate a reduction of brain glucose metabolism during intoxication and document an increase in brain acetate uptake. The opposite changes observed between regional brain metabolic decrements and regional increases in [1-11C]acetate uptake support the hypothesis that during alcohol intoxication the brain may rely on acetate as an alternative brain energy source and provides preliminary evidence that heavy alcohol exposures may facilitate the use of acetate as an energy substrate. These findings raise the question of the potential therapeutic benefits that increasing plasma acetate concentration (ie ketogenic diets) may have in alcoholics undergoing alcohol detoxification. PMID:22947541

Entropic effects in the electric double layer of model colloids with size-asymmetric monovalent ions

NASA Astrophysics Data System (ADS)

Guerrero-García, Guillermo Iván; González-Tovar, Enrique; Olvera de la Cruz, Mónica

2011-08-01

The structure of the electric double layer of charged nanoparticles and colloids in monovalent salts is crucial to determine their thermodynamics, solubility, and polyion adsorption. In this work, we explore the double layer structure and the possibility of charge reversal in relation to the size of both counterions and coions. We examine systems with various size-ratios between counterions and coions (ion size asymmetries) as well as different total ion volume fractions. Using Monte Carlo simulations and integral equations of a primitive-model electric double layer, we determine the highest charge neutralization and electrostatic screening near the electrified surface. Specifically, for two binary monovalent electrolytes with the same counterion properties but differing only in the coion's size surrounding a charged nanoparticle, the one with largest coion size is found to have the largest charge neutralization and screening. That is, in size-asymmetric double layers with a given counterion's size the excluded volume of the coions dictates the adsorption of the ionic charge close to the colloidal surface for monovalent salts. Furthermore, we demonstrate that charge reversal can occur at low surface charge densities, given a large enough total ion concentration, for systems of monovalent salts in a wide range of ion size asymmetries. In addition, we find a non-monotonic behavior for the corresponding maximum charge reversal, as a function of the colloidal bare charge. We also find that the reversal effect disappears for binary salts with large-size counterions and small-size coions at high surface charge densities. Lastly, we observe a good agreement between results from both Monte Carlo simulations and the integral equation theory across different colloidal charge densities and 1:1-elec-trolytes with different ion sizes.

Eliminating Nonlinear Acoustical Effects From Thermoacoustic Refrigeration Systems

NASA Astrophysics Data System (ADS)

Garrett, Steven L.; Smith, Robert W. M.; Poese, Matthew E.

2006-05-01

Nonlinear acoustical effects dissipate energy that degrades thermoacoustic refrigerator performance. The largest of these effects occur in acoustic resonators and include shock formation; turbulence and boundary layer disruption; and entry/exit (minor) losses induced by changes in resonator cross-sectional area. Effects such as these also make the creation of accurate performance models more complicated. Suppression of shock formation by intentional introduction of resonator anharmonicity has been common practice for the past two decades. Recent attempts to increase cooling power density by increasing pressure amplitudes has required reduction of turbulence and minor loss by using an new acousto-mechanical resonator topology. The hybrid resonator still stores potential energy in the compressibility of the gaseous working fluid, but stores kinetic energy in the moving (solid) mass of the motor and piston. This talk will first present nonlinear acoustical loss measurements obtained in a "conventional" double-Helmholtz resonator geometry (TRITON) that dissipated four kilowatts of acoustic power. We will then describe the performance of the new "bellows bounce" resonator configuration and "vibromechanical multiplier" used in the first successful implementation of this approach that created an ice cream freezer produced at Penn State for Ben & Jerry's.

Why is the electrocaloric effect so small in ferroelectrics?

DOE PAGES

Guzmán-Verri, G. G.; Littlewood, P. B.

2016-05-19

Ferroelectrics are attractive candidate materials for environmentally friendly solid state refrigeration free of greenhouse gases. Their thermal response upon variations of external electric fields is largest in the vicinity of their phase transitions, which may occur near room temperature. The magnitude of the effect, however, is too small for useful cooling applications even when they are driven close to dielectric breakdown. Insight from microscopic theory is therefore needed to characterize materials and provide guiding principles to search for new ones with enhanced electrocaloric performance. Here, we derive from well-known microscopic models of ferroelectricity meaningful figures of merit for a widemore » class of ferroelectric materials. Such figures of merit provide insight into the relation between the strength of the effect and the characteristic interactions of ferroelectrics such as dipolar forces. We find that the long range nature of these interactions results in a small effect. A strategy is proposed to make it larger by shortening the correlation lengths of fluctuations of polarization. In addition, we bring into question other widely used but empirical figures of merit and facilitate understanding of the recently observed secondary broad peak in the electrocalorics of relaxor ferroelectrics.« less

Floodplain Impact on Riverine Dissolved Carbon Cycling in the Mississippi-Atchafalaya River System

NASA Astrophysics Data System (ADS)

DelDuco, E.; Xu, Y. J.

2017-12-01

Studies have shown substantial increases in the export of terrestrial carbon by rivers over the past several decades, and have linked these increases to human activity such as changes in land use, urbanization, and intensive agriculture. The Mississippi River (MR) is the largest river in North America, and is among the largest in the world, making its carbon export globally significant. The Atchafalaya River (AR) receives 25% of the Mississippi River's flow before traveling 189 kilometers through the largest bottomland swamp in North America, providing a unique opportunity to study floodplain impacts on dissolved carbon in a large river. The aim of this study was to determine how dissolved organic carbon (DOC) and dissolved inorganic carbon (DIC) in the AR change spatially and seasonally, and to elucidate which processes control carbon cycling in this intricate swamp river system. From May 2015 -May 2016, we conducted monthly river sampling from the river's inflow to its outflow, analyzing samples for DOC and DIC concentrations and δ 13C stable isotope composition. During the study period, the river discharged a total of 5.35 Tg DIC and a total of 2.34 Tg DOC into the Gulf of Mexico. Based on the mass inflow-outflow balance, approximately 0.53 Tg ( 10%) of the total DIC exported was produced within the floodplain, while 0.24 Tg ( 10%) of DOC entering the basin was removed. The AR was consistently saturated with pCO2 above atmospheric pressure, indicating that this swamp-river system acts a large source of DIC to the atmosphere as well as to coastal margins. Largest changes in carbon constituents occurred during periods of greatest inundation of the basin, and corresponded with shifts in isotopic composition that indicated large inputs of DIC from floodplains. This effect was particularly pronounced during initial flood stages. This study demonstrates that a major river with extensive floodplains in its coastal margin can act as an important source of DIC as well as a sink for DOC. In light of increased riverine carbon export due to climate change and enhanced hydrological cycling, low-lying floodplain systems such as the AR may need to be looked to in future years for the filtration and removal of organic materials, which impact coastal margins and ocean ecosystems as a whole.

Seismic hazard map of the western hemisphere

USGS Publications Warehouse

Shedlock, K.M.; Tanner, J.G.

1999-01-01

Vulnerability to natural disasters increases with urbanization and development of associated support systems (reservoirs, power plants, etc.). Catastrophic earthquakes account for 60% of worldwide casualties associated with natural disasters. Economic damage from earthquakes is increasing, even in technologically advanced countries with some level of seismic zonation, as shown by the 1989 Loma Prieta, CA ($6 billion), 1994 Northridge, CA ($ 25 billion), and 1995 Kobe, Japan (> $ 100 billion) earthquakes. The growth of megacities in seismically active regions around the world often includes the construction of seismically unsafe buildings and infrastructures, due to an insufficient knowledge of existing seismic hazard. Minimization of the loss of life, property damage, and social and economic disruption due to earthquakes depends on reliable estimates of seismic hazard. National, state, and local governments, decision makers, engineers, planners, emergency response organizations, builders, universities, and the general public require seismic hazard estimates for land use planning, improved building design and construction (including adoption of building construction codes), emergency response preparedness plans, economic forecasts, housing and employment decisions, and many more types of risk mitigation. The seismic hazard map of the Americas is the concatenation of various national and regional maps, involving a suite of approaches. The combined maps and documentation provide a useful global seismic hazard framework and serve as a resource for any national or regional agency for further detailed studies applicable to their needs. This seismic hazard map depicts Peak Ground Acceleration (PGA) with a 10% chance of exceedance in 50 years for the western hemisphere. PGA, a short-period ground motion parameter that is proportional to force, is the most commonly mapped ground motion parameter because current building codes that include seismic provisions specify the horizontal force a building should be able to withstand during an earthquake. This seismic hazard map of the Americas depicts the likely level of short-period ground motion from earthquakes in a fifty-year window. Short-period ground motions effect short-period structures (e.g., one-to-two story buildings). The largest seismic hazard values in the western hemisphere generally occur in areas that have been, or are likely to be, the sites of the largest plate boundary earthquakes. Although the largest earthquakes ever recorded are the 1960 Chile and 1964 Alaska subduction zone earthquakes, the largest seismic hazard (PGA) value in the Americas is in Southern California (U.S.), along the San Andreas fault.

What Caused the UK's Largest Common Dolphin (Delphinus delphis) Mass Stranding Event?

PubMed Central

Jepson, Paul D.; Deaville, Robert; Acevedo-Whitehouse, Karina; Barnett, James; Brownlow, Andrew; Brownell Jr., Robert L.; Clare, Frances C.; Davison, Nick; Law, Robin J.; Loveridge, Jan; Macgregor, Shaheed K.; Morris, Steven; Murphy, Sinéad; Penrose, Rod; Perkins, Matthew W.; Pinn, Eunice; Seibel, Henrike; Siebert, Ursula; Sierra, Eva; Simpson, Victor; Tasker, Mark L.; Tregenza, Nick; Cunningham, Andrew A.; Fernández, Antonio

2013-01-01

On 9 June 2008, the UK's largest mass stranding event (MSE) of short-beaked common dolphins (Delphinus delphis) occurred in Falmouth Bay, Cornwall. At least 26 dolphins died, and a similar number was refloated/herded back to sea. On necropsy, all dolphins were in good nutritive status with empty stomachs and no evidence of known infectious disease or acute physical injury. Auditory tissues were grossly normal (26/26) but had microscopic haemorrhages (5/5) and mild otitis media (1/5) in the freshest cases. Five lactating adult dolphins, one immature male, and one immature female tested were free of harmful algal toxins and had low chemical pollutant levels. Pathological evidence of mud/seawater inhalation (11/26), local tide cycle, and the relative lack of renal myoglobinuria (26/26) suggested MSE onset on a rising tide between 06∶30 and 08∶21 hrs (9 June). Potential causes excluded or considered highly unlikely included infectious disease, gas/fat embolism, boat strike, by-catch, predator attack, foraging unusually close to shore, chemical or algal toxin exposure, abnormal weather/climatic conditions, and high-intensity acoustic inputs from seismic airgun arrays or natural sources (e.g., earthquakes). International naval exercises did occur in close proximity to the MSE with the most intense part of the exercises (including mid-frequency sonars) occurring four days before the MSE and resuming with helicopter exercises on the morning of the MSE. The MSE may therefore have been a “two-stage process” where a group of normally pelagic dolphins entered Falmouth Bay and, after 3–4 days in/around the Bay, a second acoustic/disturbance event occurred causing them to strand en masse. This spatial and temporal association with the MSE, previous associations between naval activities and cetacean MSEs, and an absence of other identifiable factors known to cause cetacean MSEs, indicates naval activity to be the most probable cause of the Falmouth Bay MSE. PMID:23646103

Predation by fallfish (Semotilus corporalis) on Pacific salmon eggs in the Salmon River, New York

USGS Publications Warehouse

Johnson, J. H.; Nack, C.C.; Chalupnicki, M.A.

2009-01-01

Fallfish (Semotilus corporalis) are the largest native cyprinid in the northeastern United States and are the most abundant native species in the Salmon River, New York. The Salmon River is a high-quality spawning and nursery river for Pacific salmon (Oncorhynchus spp.) migrating from Lake Ontario. Because of the large number of Pacific salmon spawning in the river in the fall extensive redd superimposition occurs resulting in salmonid eggs being available on the substrate. We examined the fall diet of 647 fallfish in 2007 and 2008 to determine the extent of predation on Pacific salmon eggs. The contribution of eggs in the diet significantly increased once fallfish attained a size of 100 mm total length. The largest size category of fallfish examined (≥150 mm) had the highest proportion (86.1%) of salmon eggs in their diet. The contribution of Zooplankton and chironomids in the diet of fallfish decreased with fish size. Except for the two largest groups of fallfish examined (i.e., 100–149 mm and ≥150 mm) diet overlap among size groups was low. The high contribution in the diet during the fall and high caloric value of Pacific salmon eggs could increase growth and survival of this species in the Salmon River.

Nonlinear ecosystem services response to groundwater availability under climate extremes

NASA Astrophysics Data System (ADS)

Qiu, J.; Zipper, S. C.; Motew, M.; Booth, E.; Kucharik, C. J.; Steven, L. I.

2017-12-01

Depletion of groundwater has been accelerating at regional to global scales. Besides serving domestic, industrial and agricultural needs, in situ groundwater is also a key control on biological, physical and chemical processes across the critical zone, all of which underpin supply of ecosystem services essential for humanity. While there is a rich history of research on groundwater effects on subsurface and surface processes, understanding interactions, nonlinearity and feedbacks between groundwater and ecosystem services remain limited, and almost absent in the ecosystem service literature. Moreover, how climate extremes may alter groundwater effects on services is underexplored. In this research, we used a process-based ecosystem model (Agro-IBIS) to quantify groundwater effects on eight ecosystem services related to food, water and biogeochemical processes in an urbanizing agricultural watershed in the Midwest, USA. We asked: (1) Which ecosystem services are more susceptible to shallow groundwater influences? (2) Do effects of groundwater on ecosystem services vary under contrasting climate conditions (i.e., dry, wet and average)? (3) Where on the landscape are groundwater effects on ecosystem services most pronounced? (4) How do groundwater effects depend on water table depth? Overall, groundwater significantly impacted all services studied, with the largest effects on food production, water quality and quantity, and flood regulation services. Climate also mediated groundwater effects with the strongest effects occurring under dry climatic conditions. There was substantial spatial heterogeneity in groundwater effects across the landscape that is driven in part by spatial variations in water table depth. Most ecosystem services responded nonlinearly to groundwater availability, with most apparent groundwater effects occurring when the water table is shallower than a critical depth of 2.5-m. Our findings provide compelling evidence that groundwater plays a vital role in sustaining ecosystem services. Our research highlights the pressing need to consider groundwater during the assessment and management of ecosystem services, and suggests that protecting groundwater resources may enhance ecosystem service resilience to future climate extremes and increased climate variability.

76 FR 39457 - Self-Regulatory Organizations; Notice of Filing and Immediate Effectiveness of Proposed Rule...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-06

...% of the investable U.S. equity market. \\10\\ The Russell 3000 Value Index measures the performance of... largest securities based on a combination of their market cap and current index membership. The Russell... approximately 200 of the largest securities based on a combination of their market cap and current index...

Is earthquake rate in south Iceland modified by seasonal loading?

NASA Astrophysics Data System (ADS)

Jonsson, S.; Aoki, Y.; Drouin, V.

2017-12-01

Several temporarily varying processes have the potential of modifying the rate of earthquakes in the south Iceland seismic zone, one of the two most active seismic zones in Iceland. These include solid earth tides, seasonal meteorological effects and influence from passing weather systems, and variations in snow and glacier loads. In this study we investigate the influence these processes may have on crustal stresses and stressing rates in the seismic zone and assess whether they appear to be influencing the earthquake rate. While historical earthquakes in the south Iceland have preferentially occurred in early summer, this tendency is less clear for small earthquakes. The local earthquake catalogue (going back to 1991, magnitude of completeness < 1.0) has indeed more earthquakes in summer than in winter. However, this pattern is strongly influenced by aftershock sequences of the largest M6+ earthquakes, which occurred in June 2000 and May 2008. Standard Reasenberg earthquake declustering or more involved model independent stochastic declustering algorithms are not capable of fully eliminating the aftershocks from the catalogue. We therefore inspected the catalogue for the time period before 2000 and it shows limited seasonal tendency in earthquake occurrence. Our preliminary results show no clear correlation between earthquake rates and short-term stressing variations induced from solid earth tides or passing storms. Seasonal meteorological effects also appear to be too small to influence the earthquake activity. Snow and glacier load variations induce significant vertical motions in the area with peak loading occurring in Spring (April-May) and maximum unloading in Fall (Sept.-Oct.). Early summer occurrence of historical earthquakes therefore correlates with early unloading rather than with the peak unloading or unloading rate, which appears to indicate limited influence of this seasonal process on the earthquake activity.

Effects of economic crises on population health outcomes in Latin America, 1981-2010: an ecological study.

PubMed

Williams, Callum; Gilbert, Barnabas James; Zeltner, Thomas; Watkins, Johnathan; Atun, Rifat; Maruthappu, Mahiben

2016-01-06

The relative health effects of changes in unemployment, inflation and gross domestic product (GDP) per capita on population health have not been assessed. We aimed to determine the effect of changes in these economic measures on mortality metrics across Latin America. Ecological study. Latin America (21 countries), 1981-2010. Uses multivariate regression analysis to assess the effects of changes in unemployment, inflation and GDP per capita on 5 mortality indicators across 21 countries in Latin America, 1981-2010. Country-specific differences in healthcare infrastructure, population structure and population size were controlled for. Between 1981 and 2010, a 1% rise in unemployment was associated with statistically significant deteriorations (p<0.05) in 5 population health outcomes, with largest deteriorations in 1-5 years of age and male adult mortality rates (1.14 and 0.53 rises per 1000 deaths respectively). A 1% rise in inflation rate was associated with significant deteriorations (p<0.05) in 4 population health outcomes, with the largest deterioration in male adult mortality rate (0.0033 rise per 1000 deaths). Lag analysis showed that 5 years after rises in unemployment and inflation, significant deteriorations (p<0.05) occurred in 3 and 5 mortality metrics, respectively. A 1% rise in GDP per capita was associated with no significant deteriorations in population health outcomes either in the short or long term. β coefficient comparisons indicated that the effect of unemployment increases was substantially greater than that of changes in GDP per capita or inflation. Rises in unemployment and inflation are associated with long-lasting deteriorations in several population health outcomes. Unemployment exerted much larger effects on health than inflation. In contrast, changes in GDP per capita had almost no association with the explored health outcomes. Contrary to neoclassical development economics, policymakers should prioritise amelioration of unemployment if population health outcomes are to be optimised. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Two astroblems in Ukraine - witnesses of the last days of dinosaurs

NASA Astrophysics Data System (ADS)

Vidmachenko, A. P.

2017-05-01

Moor then 65 million years ago an asteroid with a few kilometers in size with mass of 1 trillion tons created a crater Chicxulub with a diameter of 170 km on the Yucatán Peninsula in Mexico. Then the dinosaurs died out. The largest of Ukrainian astroblems is Manevichska, located in Volyn region. It has a diameter of 45 km and occurred about 65 million years ago too. In the central part of Ukraine on the border of Kirovograd and Cherkassy regions, there is Boltyshka astrobleme. The crater has diameter 25 km and depth of more than 1 km. Boltyshka crater also appeared more than 65 million years ago. These dating of the occurrence of astroblems indicates the close age of these two craters with formation of Chicxulub. If almost coinciding formation time of two or more impact structures, it is significantly increases the effect of impact on the environment and living beings.

All Africa conference on tobacco control.

PubMed Central

Chapman, S.; Yach, D.; Saloojee, Y.; Simpson, D.

1994-01-01

Although the health hazards of smoking are now generally accepted in most Western countries, the arguments have not had much impact on poorer nations. A conference on tobacco control held in Harare, Zimbabwe, in November last year was the largest to tackle this problem. The conference heard how threats of epidemics of tobacco related disease in the distant future held little weight with governments of countries that often already had massive public health problems. More immediate effects needed to be emphasised. Speakers gave three cogent arguments; firstly, the loss of capacity for foreign trade in essential goods, since most African countries are net importers of tobacco; secondly, the extensive deforestation which is occurring to fuel the flue curing of tobacco; thirdly, evidence from Papua New Guinea that raising taxation on tobacco provides governments with increased income for many years before a decrease begins. Images p190-a PMID:8312774

Major depressive disorder, cognitive symptoms, and neuropsychological performance among ethnically diverse HIV+ men and women.

PubMed

Fellows, Robert P; Byrd, Desiree A; Morgello, Susan

2013-02-01

Major depressive disorder (MDD), cognitive symptoms, and mild cognitive deficits commonly occur in HIV-infected individuals, despite highly active antiretroviral therapies. In this study, we compared neuropsychological performance and cognitive symptoms of 191 HIV-infected participants. Results indicated that participants with a formal diagnosis of current MDD performed significantly worse than participants without MDD in all seven neuropsychological domains evaluated, with the largest effect sizes in information processing speed, learning, and memory. In addition, a brief assessment of cognitive symptoms, derived from a comprehensive neuromedical interview, correlated significantly with neurocognitive functioning. Participants with MDD reported more cognitive symptoms and showed greater neurocognitive deficits than participants without MDD. These findings indicate that HIV-infected adults with MDD have more cognitive symptoms and worse neuropsychological performance than HIV-infected individuals without MDD. The results of this study have important implications for the diagnosis of HIV-associated neurocognitive disorders (HAND).

Seventy-five years of vegetation treatments on public rangelands in the Great Basin of North America

USGS Publications Warehouse

Pilliod, David S.; Welty, Justin; Toevs, Gordon R.

2017-01-01

On the Ground Land treatments occurring over millions of hectares of public rangelands in the Great Basin over the last 75 years represent one of the largest vegetation manipulation and restoration efforts in the world.The ability to use legacy data from land treatments in adaptive management and ecological research has improved with the creation of the Land Treatment Digital Library (LTDL), a spatially explicit database of land treatments conducted by the U.S. Bureau of Land Management.The LTDL contains information on over 9,000 confirmed land treatments in the Great Basin, composed of seedings (58%), vegetation control treatments (24%), and other types of vegetation or soil manipulations (18%).The potential application of land treatment legacy data for adaptive management or as natural experiments for retrospective analyses of effects of land management actions on physical, hydrologic, and ecologic patterns and processes is considerable and just beginning to be realized.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Jae Wook; Artyukhin, Sergei; Mun, Eun Deok

In this paper, we report the discovery of a metamagnetic phase transition in a polar antiferromagnet Ni 3TeO 6 that occurs at 52 T. The new phase transition accompanies a colossal magnetoelectric effect, with a magnetic-field-induced polarization change of 0.3 μC/cm 2, a value that is 4 times larger than for the spin-flop transition at 9 T in the same material, and also comparable to the largest magnetically induced polarization changes observed to date. Via density-functional calculations we construct a full microscopic model that describes the data. We model the spin structures in all fields and clarify the physics behindmore » the 52 T transition. The high-field transition involves a competition between multiple different exchange interactions which drives the polarization change through the exchange-striction mechanism. Finally, the resultant spin structure is rather counterintuitive and complex, thus providing new insights on design principles for materials with strong magnetoelectric coupling.« less

A free flight investigation of transonic sting interference

NASA Technical Reports Server (NTRS)

Jaffe, P.

1975-01-01

Transonic sting interference has been studied in a supersonic wind tunnel to obtain free flight and sting support data on identical models. The two principal configurations, representing fuselage bodies, were cigar shaped with tail fins. The others were a sharp 10-deg cone, a sphere, and a blunt entry body. Comparative data indicated that the sting had an appreciable effect on drag for the fuselage-like configurations; drag rise occurred 0.02 Mach number earlier in free flight, and drag level was 15% greater. The spheres and the blunt bodies were insensitive to the presence of stings regardless of their size. The 10-deg cones were in between, experiencing no drag difference with a minimum diameter sting, but a moderate difference with the largest diameter sting tested. All data tend to confirm the notion that for the more slender bodies the sting not only affects flow but the forebody flow as well.

Changes in polyphenolics during maturation of Java plum (Syzygium cumini Lam.).

PubMed

Lestario, Lydia Ninan; Howard, Luke R; Brownmiller, Cindi; Stebbins, Nathan B; Liyanage, Rohana; Lay, Jackson O

2017-10-01

Java plum (Syzygium cumini Lam.) is a rich source of polyphenolics with many purported health benefits, but the effect of maturation on polyphenolic content is unknown. Freeze-dried samples of Java plum from seven different maturity stages were analyzed for anthocyanin, flavonol, flavanonol and hydrolysable tannin composition by HPLC. Anthocyanins were first detected at the green-pink stage of maturity and increased throughout maturation with the largest increase occurring from the dark purple to black stages of maturation. Levels of gallotannins, ellagitannins, flavonols, gallic acid and ellagic acid were highest at early stages of maturation and decreased as the fruit ripened. For production of antioxidant-rich nutraceutical ingredients, fruit should be harvested immature to obtain extracts rich in hydrolysable tannins and flavonols. The exceptional anthocyanin content of black fruit may prove useful as a source of a natural colorant. Copyright © 2017 Elsevier Ltd. All rights reserved.

The impact of a 2 X CO2 climate on lightning-caused fires

NASA Technical Reports Server (NTRS)

Price, Colin; Rind, David

1994-01-01

Future climate change could have significant repercussions for lightning-caused wildfires. Two empirical fire models are presented relating the frequency of lightning fires and the area burned by these fires to the effective precipitation and the frequency of thunderstorm activity. One model deals with the seasonal variations in lightning fires, while the second model deals with the interannual variations of lightning fires. These fire models are then used with the Goddard Institute for Space Studies General Circulation Model to investigate possible changes in fire frequency and area burned in a 2 X CO2 climate. In the United States, the annual mean number of lightning fires increases by 44%, while the area burned increases by 78%. On a global scale, the largest increase in lightning fires can be expected in untouched tropical ecosystems where few natural fires occur today.

Efficient non-linear two-photon effects from the Cesium 6D manifold

NASA Astrophysics Data System (ADS)

Haluska, Nathan D.; Perram, Glen P.; Rice, Christopher A.

2018-02-01

We report several non-linear process that occur when two-photon pumping the cesium 6D states. Cesium vapor possess some of the largest two-photon pump cross sections in nature. Pumping these cross sections leads to strong amplified spontaneous emission that we observe on over 17 lasing lines. These new fields are strong enough to couple with the pump to create additional tunable lines. We use a heat pipe with cesium densities of 1014 to 1016 cm-3 and 0 to 5 Torr of helium buffer gas. The cesium 6D States are interrogated by both high energy pulses and low power CW sources. We observe four-wave mixing, six-wave mixing, potential two-photon lasing, other unknown nonlinear processes, and the persistence of some processes at low thresholds. This system is also uniquely qualified to support two-photon lasing under the proper conditions.

The effects of increased CO[sub 2] on the competitive ability of Lupinus arboreus, a dominant nitrogen-fixing shrub

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wallace, A.M.

Plant responses to increased atmospheric CO[sub 2] have been shown to be both species-specific and dependent on other environmental factors, potentially changing competitive interactions and altering community structure. The competitive response of a dominant nitrogen-fixing shrub to an introduced annual (Bromus diandrus) and a native perennial grass (Bromus carinatus) was measured under ambient and high CO[sub 2] and two nitrogen levels. These species coexist in a generally nitrogen-limited coastal grassland reserve besieged with alien species. The relative competitive ability of the lupin increased with CO[sub 2] for all treatments, with the largest difference occurring at low nitrogen in competition withmore » the introduced annual. This study provides a global change perspective for those interested in conserving native Californian grassland species, as well as the first data on the competitive response of nitrogen-fixers to high CO[sub 2].« less

A new threat to human reproduction system posed by Zika virus (ZIKV): From clinical investigations to experimental studies.

PubMed

Li, Xiangdong; Ma, Wenqiang; Wong, Gary; Ma, Shuoqian; Li, Shihua; Bi, Yuhai; Gao, George F

2017-09-08

Zika virus (ZIKV) was first isolated in 1947 from a rhesus monkey in the Zika forest of Uganda. ZIKV has since been silently circulating in a number of equatorial countries for over 50 years. The largest outbreak in humans occurred in Brazil in 2015-2016. Unlike its flavivirus relatives, sexual and post-transfusion transmissions of ZIKV have been reported. In addition, fetal infection can result in microcephaly and congenital Zikv syndrome has been reported in neonates. Moreover, ZIKV RNA can persist for at least 6 months in semen and 11 weeks in vaginal secretions after the infection, suggesting potential tropism for the male and female genital tracts. Accordingly, it is important to determine whether genital ZIKV infection could have deleterious effects on the male and female reproductive systems. Copyright © 2017. Published by Elsevier B.V.

Substance abuse treatment organizations as mediators of social policy: slowing the adoption of a congressionally approved medication.

PubMed

Wallack, Stanley S; Thomas, Cindy Parks; Martin, Timothy C; Chilingerian, Jon; Reif, Sharon

2010-01-01

Most substance abuse treatment occurs in outpatient treatment centers, necessitating an understanding of what motivates organizations to adopt new treatment modalities. Tichy's framework of organizations as being comprised of three intertwined internal systems (technical, cultural, and political) was used to explain treatment organizations' slow adoption of buprenorphine, a new medication for opiate dependence. Primary data were collected from substance abuse treatment organizations in four of the ten metropolitan areas with the largest number of heroin users. Only about one fifth offered buprenorphine. All three internal systems were important determinants of buprenorphine adoption in our multivariate model. However, the cultural system, measured by attitude toward medications, was a necessary condition for adoption. Health policies designed to encourage adoption of evidence-based performance measures typically focus on the technical system of organizations. These findings suggest that such policies would be more effective if they incorporate an understanding of all three internal systems.

Emergent dynamics of laboratory insect swarms

NASA Astrophysics Data System (ADS)

Kelley, Douglas H.; Ouellette, Nicholas T.

2013-01-01

Collective animal behaviour occurs at nearly every biological size scale, from single-celled organisms to the largest animals on earth. It has long been known that models with simple interaction rules can reproduce qualitative features of this complex behaviour. But determining whether these models accurately capture the biology requires data from real animals, which has historically been difficult to obtain. Here, we report three-dimensional, time-resolved measurements of the positions, velocities, and accelerations of individual insects in laboratory swarms of the midge Chironomus riparius. Even though the swarms do not show an overall polarisation, we find statistical evidence for local clusters of correlated motion. We also show that the swarms display an effective large-scale potential that keeps individuals bound together, and we characterize the shape of this potential. Our results provide quantitative data against which the emergent characteristics of animal aggregation models can be benchmarked.

RACORO Extended-Term Aircraft Observations of Boundary-Layer Clouds

NASA Technical Reports Server (NTRS)

Vogelmann, Andrew M.; McFarquhar, Greg M.; Ogren, John A.; Turner, David D.; Comstock, Jennifer M.; Feingold, Graham; Long, Charles N.; Jonsson, Haflidi H.; Bucholtz, Anthony; Collins, Don R.;

Gamma-ray Astrophysics: a New Look at the Universe

NASA Technical Reports Server (NTRS)

Trombka, J. I.; Fichtel, C. E.; Grindlay, J.; Hofstadter, R.

1978-01-01

Gamma-ray astronomy which includes the spectral region from above approximately 100 keV to greater than or equal to 1000 GeV permits investigation of the most energetic photons originating in our galaxy and beyond and provides the most direct means of studying the largest transfers of energy occurring in astrophysical processes. Of all the electromagnetic spectrum, high-energy gamma-ray astronomy measures most directly the presence and dynamic effects of the energetic charged cosmic ray particles, element synthesis, and particle acceleration. Further, gamma rays suffer negligible absorption or scatterings as they travel in straight paths; hence, they may survive billions of years and still reveal their source. The high energy processes in stellar objects (including our Sun), the dynamics of the cosmic-ray gas, the formation of clouds and nebulae, galactic evolution and even certain aspects of cosmology and the origin of the universe may be explored by gamma-ray observations.

Conjunction Assessment Late-Notice High-Interest Event Investigation: Space Weather Aspects

NASA Technical Reports Server (NTRS)

Pachura, D.; Hejduk, M. D.

2016-01-01

Late-notice events usually driven by large changes in primary (protected) object or secondary object state. Main parameter to represent size of state change is component position difference divided by associated standard deviation (epsilon divided by sigma) from covariance. Investigation determined actual frequency of large state changes, in both individual and combined states. Compared them to theoretically expected frequencies. Found that large changes ( (epsilon divided by sigma) is greater than 3) in individual object states occur much more frequently than theory dictates. Effect is less pronounced in radial components and in events with probability of collision (Pc) greater than 1 (sup -5) (1e-5). Found combined state matched much closer to theoretical expectation, especially for radial and cross-track. In-track is expected to be the most vulnerable to modeling errors, so not surprising that non-compliance largest in this component.

Confronting inconsistencies in the amphibian-chytridiomycosis system: implications for disease management.

PubMed

Venesky, Matthew D; Raffel, Thomas R; McMahon, Taegan A; Rohr, Jason R

2014-05-01

Chytridiomycosis, caused by the pathogenic fungus Batrachochytrium dendrobatidis (Bd), is one of the largest threats to wildlife and is putatively linked to the extirpation of numerous amphibians. Despite over a decade of research on Bd, conflicting results from a number of studies make it difficult to forecast where future epizootics will occur and how to manage this pathogen effectively. Here, we emphasize how resolving these conflicts will advance Bd management and amphibian conservation efforts. We synthesize current knowledge on whether Bd is novel or endemic, whether amphibians exhibit acquired resistance to Bd, the importance of host resistance versus tolerance to Bd, and how biotic (e.g. species richness) and abiotic factors (e.g. climate change) affect Bd abundance. Advances in our knowledge of amphibian-chytrid interactions might inform the management of fungal pathogens in general, which are becoming more common and problematic globally. © 2013 The Authors. Biological Reviews © 2013 Cambridge Philosophical Society.

Age differences in genetic and environmental influences on weight and shape concerns.

PubMed

Klump, Kelly L; Burt, S Alexandra; Spanos, Alexia; McGue, Matt; Iacono, William G; Wade, Tracey D

2010-12-01

Previous research has shown important developmental shifts ingenetic and environmental influences for disordered eating. However, little research has examined age differences for weight/shape concerns, two key components of eating disorders. The goal of this study was to investigate these age differences in preadolescent, adolescent, young adult, and mid-adult twins. Participants included 2,618 female twins (ages of 10-41 years) from three large twin registries. Shape and weight concerns were assessed with the Eating Disorders Examination Questionnaire. Genetic influences were modest in preadolescent twins, but significant from early-adolescence through middle adulthood. Shared environmental factors showed the opposite pattern, with the largest shared environmental contributions occurring in the youngest age group. Nonshared environmental effects remained relatively constant across age. Findings highlight the importance of age differences in genetic and environmental influences. Possible mechanisms include gene x environment interactions and biological changes associated with key developmental stages. © 2009 by Wiley Periodicals, Inc.

Observational data needs for plasma phenomena

NASA Technical Reports Server (NTRS)

Niedner, M. B., Jr.

1981-01-01

Bright comets display a rich variety of interesting plasma phenomena which occur over an enormous range of spatial scales, and which require different observational techniques to be studied effectively. Wide-angle photography of high time resolution is probably the best method of studying the phenomenon of largest known scale: the plasma tail disconnection event (DE), which has been attributed to magnetic reconnection at interplanetary sector boundary crossings. These structures usually accelerate as they recede from the head region and observed velocities are typically in the range 50 V km/s. They are often visible for several days following the time of disconnection, and are sometimes seen out past 0.2 AU from the cometary head. The following areas pertaining to plasma phenomena in the ionoshere are addressed: the existence, size, and heliocentric distance variations of the contact surface, and the observational signatures of magnetic reconnection at sector boundary crossings.

Man made deltas

PubMed Central

Maselli, Vittorio; Trincardi, Fabio

2013-01-01

The review of geochronological and historical data documents that the largest southern European deltas formed almost synchronously during two short intervals of enhanced anthropic pressure on landscapes, respectively during the Roman Empire and the Little Ice Age. These growth phases, that occurred under contrasting climatic regimes, were both followed by generalized delta retreat, driven by two markedly different reasons: after the Romans, the fall of the population and new afforestation let soil erosion in river catchments return to natural background levels; since the industrial revolution, instead, flow regulation through river dams overkill a still increasing sediment production in catchment basins. In this second case, furthermore, the effect of a reduced sediment flux to the coasts is amplified by the sinking of modern deltas, due to land subsidence and sea level rise, that hampers delta outbuilding and increases the vulnerability of coastal zone to marine erosion and flooding. PMID:23722597

Effects of crude Dubai oil on Salmo gairdneri Rich. and Carassius auratus L

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ramusino, M.C.; Dellavedova, P.; Zanzottera, D.

1984-03-01

In 1980, owing to the bursting of an oil pipeline, about 663 tons of crude Dubai oil poured into the river Po, the largest Italian river (northern Italy). The aim of this work was to try and identify, by way of laboratory tests, the lethal concentrations and subsequently calculate the concentration threshold value, below which mortality does not occur (safety dose). In planning and carrying out the experiments the methodological problems encountered were many, arising from the nature of the toxicants and the lack of bibliographical references about pollution by hydrocarbons of a river ecosystem. The focal point of themore » problem is precisely the absence of a working method for tests with hydrocarbons. This makes the preparation of test solutions and the exposure of the animals to the toxic important for the validity of the entire work.« less

Coccidioidomycosis Outbreaks, United States and Worldwide, 1940-2015.

PubMed

Freedman, Michael; Jackson, Brendan R; McCotter, Orion; Benedict, Kaitlin

2018-03-01

Coccidioidomycosis causes substantial illness and death in the United States each year. Although most cases are sporadic, outbreaks provide insight into the clinical and environmental features of coccidioidomycosis, high-risk activities, and the geographic range of Coccidioides fungi. We identified reports published in English of 47 coccidioidomycosis outbreaks worldwide that resulted in 1,464 cases during 1940-2015. Most (85%) outbreaks were associated with environmental exposures; the 2 largest outbreaks resulted from an earthquake and a large dust storm. More than one third of outbreaks occurred in areas where the fungus was not previously known to be endemic, and more than half of outbreaks involved occupational exposures. Coccidioidomycosis outbreaks can be difficult to detect and challenging to prevent given the unknown effectiveness of environmental control methods and personal protective equipment; therefore, increased awareness of coccidioidomycosis outbreaks is needed among public health professionals, healthcare providers, and the public.

Spatial variation in extreme winds predicts large wildfire locations in chaparral ecosystems

NASA Astrophysics Data System (ADS)

Moritz, Max A.; Moody, Tadashi J.; Krawchuk, Meg A.; Hughes, Mimi; Hall, Alex

2010-02-01

Fire plays a crucial role in many ecosystems, and a better understanding of different controls on fire activity is needed. Here we analyze spatial variation in fire danger during episodic wind events in coastal southern California, a densely populated Mediterranean-climate region. By reconstructing almost a decade of fire weather patterns through detailed simulations of Santa Ana winds, we produced the first high-resolution map of where these hot, dry winds are consistently most severe and which areas are relatively sheltered. We also analyzed over half a century of mapped fire history in chaparral ecosystems of the region, finding that our models successfully predict where the largest wildfires are most likely to occur. There is a surprising lack of information about extreme wind patterns worldwide, and more quantitative analyses of their spatial variation will be important for effective fire management and sustainable long-term urban development on fire-prone landscapes.

Hepatitis A Incidence and Hepatitis A Vaccination Among American Indians and Alaska Natives, 1990–2001

PubMed Central

Bialek, Stephanie R.; Thoroughman, Douglas A.; Hu, Diana; Simard, Edgar P.; Chattin, Jody; Cheek, Jim; Bell, Beth P.

2004-01-01

Objectives. We assessed the effect on trends in hepatitis A incidence of the 1996 recommendation for routine hepatitis A vaccination of American Indian/Alaska Native (AIAN) children. Methods. We examined trends in hepatitis A incidence among AIAN peoples during 1990–2001 and vaccination coverage levels among children on the largest American Indian reservation. Results. Hepatitis A rates among AIANs declined 20-fold during 1997–2001. Declines in hepatitis A incidence occurred among AIANs in reservation and metropolitan areas. Among 1956 children living on the Navajo Nation whose medical records were reviewed, 1508 (77.1%) had received at least one dose of hepatitis A vaccine, and 1020 (52.1%) had completed the vaccine series. Conclusions. Hepatitis A rates among AIAN peoples have declined dramatically coincident with implementation of routine hepatitis A vaccination of AIAN children. PMID:15249305

Coccidioidomycosis Outbreaks, United States and Worldwide, 1940–2015

PubMed Central

Freedman, Michael; Jackson, Brendan R.; McCotter, Orion

2018-01-01

Coccidioidomycosis causes substantial illness and death in the United States each year. Although most cases are sporadic, outbreaks provide insight into the clinical and environmental features of coccidioidomycosis, high-risk activities, and the geographic range of Coccidioides fungi. We identified reports published in English of 47 coccidioidomycosis outbreaks worldwide that resulted in 1,464 cases during 1940–2015. Most (85%) outbreaks were associated with environmental exposures; the 2 largest outbreaks resulted from an earthquake and a large dust storm. More than one third of outbreaks occurred in areas where the fungus was not previously known to be endemic, and more than half of outbreaks involved occupational exposures. Coccidioidomycosis outbreaks can be difficult to detect and challenging to prevent given the unknown effectiveness of environmental control methods and personal protective equipment; therefore, increased awareness of coccidioidomycosis outbreaks is needed among public health professionals, healthcare providers, and the public. PMID:29460741

Microwave Limb Sounder Measurements Depicting the Relationship Between Nitrous Oxide Levels and

NASA Technical Reports Server (NTRS)

2005-01-01

Aura's Microwave Limb Sounder measures nitrous oxide, which is unaffected by stratospheric chemical processes. By studying changes in its levels, scientists can better understand how air is moving around and how ozone is affected by that air motion, allowing them to differentiate those changes from the ones caused by chemical ozone destruction. In these cross-sections of nitrous oxide (top) and ozone (bottom) data from Aura, changes in the levels of these two chemicals at various temperatures and latitudes are depicted over time. The white contour shows the approximate location of the polar vortex boundary.

The left panel data were collected on January 23, 2005, near the beginning of chemical ozone destruction this winter. Virtually all chemical loss occurred before March 10 (center panel). Ozone destruction extended throughout the polar vortex from about 15-20 kilometers (9-13 miles), but occurred only in the outer part of the vortex from 20-25 kilometers (13-16 miles). The differences between the two days are depicted in the right panel. The largest observed difference is about a 1.2 parts per million by volume decrease in ozone. Plots of nitrous oxide show a decrease in the region in the outer part of the vortex where most ozone loss occurs, indicating that air from above (where nitrous oxide is lower) has moved into this region. This downward motion brings higher ozone into the region where chemical loss is occurring, thus partially masking the effects of chemical loss. Calculations using Microwave Limb Sounder data to separate dynamical and chemical effects indicate maximum chemical ozone loss of approximately 2 parts per million by volume (approximately 60 percent) in the outer part of the vortex near 18-21 kilometers (11-13 miles), and approximately 1.5 parts per million by volume when averaged throughout the whole vortex region.

Drag increase and drag reduction found in phytoplankton and bacterial cultures in laminar flow: Are cell surfaces and EPS producing rheological thickening and a Lotus-leaf Effect?

NASA Astrophysics Data System (ADS)

Jenkinson, Ian R.; Sun, Jun

2014-03-01

The laminar-flow viscosity of ocean and other natural waters consists of a Newtonian aqueous component contributed by water and salts, and a non-Newtonian one contributed mainly by exopolymeric polymers (EPS) derived largely from planktonic algae and bacteria. Phytoplankton and EPS form thin layers in stratified waters, often associated with density discontinuities. A recent model (Jenkinson and Sun, 2011. J. Plankton Res., 33, 373-383) investigated possible thalassorheological control of pycnocline thickness (PT) by EPS secreted by the harmful dinoflagellate Karenia mikimotoi. The model, based on published measurements of viscosity increase by this species, found that whether it can influence PT depends on the relationship between increased viscosity, deformation rates/stresses and length scale, which the present work has investigated. To do this, flow rate vs. hydrostatic pressure (and hence wall stress) was measured in cultures (relative to that in reference water) in capillaries of 5 radii 0.35-1.5 mm, close to oceanic-turbulence Kolmogorov length. We compared cultures of the potentially harmful algae, K. mikimotoi, Alexandrium catenella, Prorocentrum donghaiense, Skeletonema costatum, Phaeodactylum tricornutum and the bacterium Escherichia coli. Drag increase, ascribed to rheological thickening by EPS, occurred in the smallest capillaries, but drag reduction (DR) occurred in the largest ones. Since this occurred at Reynolds numbers Re too small for turbulence (or turbulent DR) to occur, this was laminar-flow DR. It may have been superhydrophobic DR (SDR), associated with the surfaces of the plankton and bacteria. SDR is associated with the self-cleaning Lotus-leaf Effect, in which water and dirt are repelled from surfaces bearing nm- to μm-sized irregularities coated with hydrophobic polymers. Because DR decreased measured viscosity and EPS thickening increased it, we could not validate the model. DR, however, represents hitherto unknown phenomenon in the oceans. Along with rheological thickening, Laminar-Flow DR may represent a new tool for plankton to manage ambient flow fields.

The 12th June 2017 Mw = 6.3 Lesvos earthquake from detailed seismological observations

NASA Astrophysics Data System (ADS)

Papadimitriou, P.; Kassaras, I.; Kaviris, G.; Tselentis, G.-A.; Voulgaris, N.; Lekkas, E.; Chouliaras, G.; Evangelidis, C.; Pavlou, K.; Kapetanidis, V.; Karakonstantis, A.; Kazantzidou-Firtinidou, D.; Fountoulakis, I.; Millas, C.; Spingos, I.; Aspiotis, T.; Moumoulidou, A.; Skourtsos, E.; Antoniou, V.; Andreadakis, E.; Mavroulis, S.; Kleanthi, M.

2018-04-01

A major earthquake (Mwö=ö6.3) occurred on the 12th of June 2017 (12:28 GMT) offshore, south of the SE coast of Lesvos Island, at a depth of 13ökm, in an area characterized by normal faulting with an important strike-slip component in certain cases. Over 900 events of the sequence between 12 and 30 June 2017 were manually analyzed and located, employing an optimized local velocity model. Double-difference relocation revealed seven spatially separated groups of events, forming two linear branches, roughly aligned N130°E, compatible with the strike of known mapped faults along the southern coast of Lesvos Island. Spatiotemporal analysis indicated gradual migration of seismicity towards NW and SE from the margins of the main rupture, while a strong secondary sequence at a separate fault patch SE of the mainshock, oriented NW-SE, was triggered by the largest aftershock (Mwö=ö5.2) that occurred on 17 June. The focal mechanisms of the mainshock (φö=ö122°, δö=ö40° and λö=ö-83°) and of the major aftershocks were determined using regional moment tensor inversion. In most cases normal faulting was revealed with the fault plane oriented in a NW-SE direction, dipping SW, with the exception of the largest aftershock that was characterized by strike-slip faulting. Stress inversion revealed a complex stress field south of Lesvos, related both to normal, in an approximate E-W direction, and strike-slip faulting. All aftershocks outside the main rupture, where gradual seismicity migration was observed, are located within the positive lobes of static stress transfer determined by applying the Coulomb criterion for the mainshock. Stress loading on optimal faults under a strike-slip regime explains the occurrence of the largest aftershock and the seismicity that was triggered at the eastern patch of the rupture zone.

Photospheric Current Spikes And Their Possible Association With Flares - Results from an HMI Data Driven Model

NASA Astrophysics Data System (ADS)

Goodman, M. L.; Kwan, C.; Ayhan, B.; Eric, S. L.

2016-12-01

A data driven, near photospheric magnetohydrodynamic model predicts spikes in the horizontal current density, and associated resistive heating rate. The spikes appear as increases by orders of magnitude above background values in neutral line regions (NLRs) of active regions (ARs). The largest spikes typically occur a few hours to a few days prior to M or X flares. The spikes correspond to large vertical derivatives of the horizontal magnetic field. The model takes as input the photospheric magnetic field observed by the Helioseismic & Magnetic Imager (HMI) on the Solar Dynamics Observatory (SDO) satellite. This 2.5 D field is used to determine an analytic expression for a 3 D magnetic field, from which the current density, vector potential, and electric field are computed in every AR pixel for 14 ARs. The field is not assumed to be force-free. The spurious 6, 12, and 24 hour Doppler periods due to SDO orbital motion are filtered out of the time series of the HMI magnetic field for each pixel. The subset of spikes analyzed at the pixel level are found to occur on HMI and granulation scales of 1 arcsec and 12 minutes. Spikes are found in ARs with and without M or X flares, and outside as well as inside NLRs, but the largest spikes are localized in the NLRs of ARs with M or X flares. The energy to drive the heating associated with the largest current spikes comes from bulk flow kinetic energy, not the electromagnetic field, and the current density is highly non-force free. The results suggest that, in combination with the model, HMI is revealing strong, convection driven, non-force free heating events on granulation scales, and it is plausible these events are correlated with subsequent M or X flares. More and longer time series need to be analyzed to determine if such a correlation exists.

Elevation change (2000-2004) on the Malaspina Glacier, Alaska

NASA Technical Reports Server (NTRS)

Sauber, J.; Molnia, B.; Carabajal, C.; Luthcke, S.; Muskett, R.

2005-01-01

The glaciers of the southeastern Alaska coastal region are the largest temperate glacier meltwater source on Earth and may contribute one third of the total glacier meltwater entering the global ocean. Since melt onset and refreeeze timing in this region show a tendency toward earlier onset and longer ablation seasons, accelerated glacier wastage may be occurring. In this study we focus on one of the largest temperate glacier systems on Earth, the Malaspina Glacier. This glacier, with a length of approximately 110 km and an area of approximately square 5,000 km, has the largest piedmont lobe of any temperate glacier. The entire lobe, which lies at elevations below 600 m, is within the ablation zone. We report and interpret ice elevation change between a digital elevation model (DEM) derived from the Shuttle Radar Topography Mission (SRTM C band) observations in Feb. 2000 and ICESat Laser 1-3 observations between Feb. 2003 and Nov. 2004. We use these elevation change results, along with earlier studies, to address the spatial and temporal variability in wastage of the piedmont lobe. Between 2000 and 2004 ice elevation changes of 10-30 meters occurred across the central Malaspina piedmont lobe. From 1972/73 (USGS DEM) to 1999 (SRTM corrected for estimated winter snow accumulation) Malaspina's (Agassiz, Seward Lobe, and Marvine) mean ice thinning was estimated at -47 m with maximum thinning on parts of the lobes to -160 m. The Malaspina's accumulation area is only slightly larger than its ablation area (2,575 km2 vs. 2,433 km2); unfortunately few glaciological observations are available from this source region. Snow accumulation rates have been largely inferred from low-altitude precipitation and temperature data. Comparing sequential ICESat observations in the Malaspina source region, we estimated short-term elevation increases of up to 5 meters during the winter of 2003/04.

Seismic hazard maps of Mexico, the Caribbean, and Central and South America

USGS Publications Warehouse

Tanner, J.G.; Shedlock, K.M.

2004-01-01

The growth of megacities in seismically active regions around the world often includes the construction of seismically unsafe buildings and infrastructures due to an insufficient knowledge of existing seismic hazard and/or economic constraints. Minimization of the loss of life, property damage, and social and economic disruption due to earthquakes depends on reliable estimates of seismic hazard. We have produced a suite of seismic hazard estimates for Mexico, the Caribbean, and Central and South America. One of the preliminary maps in this suite served as the basis for the Caribbean and Central and South America portion of the Global Seismic Hazard Map (GSHM) published in 1999, which depicted peak ground acceleration (pga) with a 10% chance of exceedance in 50 years for rock sites. Herein we present maps depicting pga and 0.2 and 1.0 s spectral accelerations (SA) with 50%, 10%, and 2% chances of exceedance in 50 years for rock sites. The seismicity catalog used in the generation of these maps adds 3 more years of data to those used to calculate the GSH Map. Different attenuation functions (consistent with those used to calculate the U.S. and Canadian maps) were used as well. These nine maps are designed to assist in global risk mitigation by providing a general seismic hazard framework and serving as a resource for any national or regional agency to help focus further detailed studies required for regional/local needs. The largest seismic hazard values in Mexico, the Caribbean, and Central and South America generally occur in areas that have been, or are likely to be, the sites of the largest plate boundary earthquakes. High hazard values occur in areas where shallow-to-intermediate seismicity occurs frequently. ?? 2004 Elsevier B.V. All rights reserved.

Recent trends in the probability of high out-of-pocket medical expenses in the United States

PubMed Central

Baird, Katherine E

2016-01-01

Objective: This article measures the probability that out-of-pocket expenses in the United States exceed a threshold share of income. It calculates this probability separately by individuals’ health condition, income, and elderly status and estimates changes occurring in these probabilities between 2010 and 2013. Data and Method: This article uses nationally representative household survey data on 344,000 individuals. Logistic regressions estimate the probabilities that out-of-pocket expenses exceed 5% and alternatively 10% of income in the two study years. These probabilities are calculated for individuals based on their income, health status, and elderly status. Results: Despite favorable changes in both health policy and the economy, large numbers of Americans continue to be exposed to high out-of-pocket expenditures. For instance, the results indicate that in 2013 over a quarter of nonelderly low-income citizens in poor health spent 10% or more of their income on out-of-pocket expenses, and over 40% of this group spent more than 5%. Moreover, for Americans as a whole, the probability of spending in excess of 5% of income on out-of-pocket costs increased by 1.4 percentage points between 2010 and 2013, with the largest increases occurring among low-income Americans; the probability of Americans spending more than 10% of income grew from 9.3% to 9.6%, with the largest increases also occurring among the poor. Conclusion: The magnitude of out-of-pocket’s financial burden and the most recent upward trends in it underscore a need to develop good measures of the degree to which health care policy exposes individuals to financial risk, and to closely monitor the Affordable Care Act’s success in reducing Americans’ exposure to large medical bills. PMID:27651901

Mississippi River Delta, Louisiana as seen from STS-62

NASA Technical Reports Server (NTRS)

1994-01-01

The Mississippi River Delta, Louisiana as seen from STS-62, is the largest river system in North America. The interdistributary bays are extremely shallow, usually less than a few meters, and contain brackish to normal marine waters except during times of flooding, when fresh water fills the bays. Sedimentation within the bays is very low, occurring only during flood periods. Along the west side of the river, a highway has been built southeastward to Venice.

Two-Color V and R CCD Photometry of the SW Sex-Type Eclipsing Cataclysmic Variable V1315 Aql

NASA Astrophysics Data System (ADS)

Andronov, I. L.; Baklanov, A. V.; Burwitz, V.

2005-08-01

The V-R color index shows a complicated behaviour during the eclipse, being largest at the brightness minimum, but showing asymmetric minima at phases -0.07 and +0.13. The hump at the light curve occurs after the eclipse, contrary to systems with the "hot spot". The phases of minima in V and R are 0.0092(17) and 0.0062(17), respectively, for the mean date JD=2453202.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anderson, W.F.; Martinell, J.; Whitney, J.B. III

The group of diseases called the thalassemias is the largest single-gene health problem in the world according the World Health Organization. The thalassemias are lethal hereditary anemias in which the infants cannot make their own blood. Three mouse mutants are shown to be models of the human disease ..cap alpha..-thalassemia. However, since an additional gene is affected, these mutants represent a particularly severe condition in which death occurs in the homozygous embryo even before globin genes are activated. Phenotypic and genotypic characteristics are described. (ACR)

Objective detection and forecasting of Clear-Air Turbulence (CAT): A status report

NASA Technical Reports Server (NTRS)

Keller, John L.

1988-01-01

Clear-air turbulence has become the largest single cause of weather-related injuries occurring in commercial carriers at cruising altitudes. A technique for objective operational CAT detection (the SCATR index) has been formulated. Its physical basis ties CAT to total energy dissipation as a response to meso- and synoptic-scale dynamical processes associated with upper-level jet stream/frontal zones. Early case studies using properly analyzed routine RAOB rawinsonde sounding data have shown promise.

How Deployments Affect the Capacity and Utilization of Army Treatment Facilities

DTIC Science & Technology

2014-01-01

and nurse practitioner —accounted for the majority of the increase in non-active-duty providers in the 14 MTFs, with the largest growth occurring...parents to decline dra- matically when soldiers deploy, we do not know the extent to which need is unmet. While we are cautioned in prior research that... needed , and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of this collection of

Spatial correlation of the dynamic propensity of a glass-forming liquid

NASA Astrophysics Data System (ADS)

Razul, M. Shajahan G.; Matharoo, Gurpreet S.; Poole, Peter H.

2011-06-01

We present computer simulation results on the dynamic propensity (as defined by Widmer-Cooper et al 2004 Phys. Rev. Lett. 93 135701) in a Kob-Andersen binary Lennard-Jones liquid system consisting of 8788 particles. We compute the spatial correlation function for the dynamic propensity as a function of both the reduced temperature T, and the time scale on which the particle displacements are measured. For T <= 0.6, we find that non-zero correlations occur at the largest length scale accessible in our system. We also show that a cluster-size analysis of particles with extremal values of the dynamic propensity, as well as 3D visualizations, reveal spatially correlated regions that approach the size of our system as T decreases, consistently with the behavior of the spatial correlation function. Next, we define and examine the 'coordination propensity', the isoconfigurational average of the coordination number of the minority B particles around the majority A particles. We show that a significant correlation exists between the spatial fluctuations of the dynamic and coordination propensities. In addition, we find non-zero correlations of the coordination propensity occurring at the largest length scale accessible in our system for all T in the range 0.466 < T < 1.0. We discuss the implications of these results for understanding the length scales of dynamical heterogeneity in glass-forming liquids.

[Submicroscopic changes in ciliated cells of the epithelium of the oviduct in cows during the estrus cycle].

PubMed

Uhrín, V; Kliment, J

1983-03-01

The submicroscopic changes in the ciliary cells of the ampullar part of oviduct are of qualitative as well as quantitative nature. The mitochondria are mainly located in the supranuclear region. They are small, having densely arranged lamelliform cristae and dense matrix. They have the largest volume in metoestrus and the highest number and the largest surface already during oestrus. The volume and surface of granular endoplasmic reticulum culminates already during pro-oestrus. The reticulum occurs mainly over the nucleus where it produces tubuli densely covered with ribosomes which begin to dilate already during pro-oestrus. The Golgi apparatus and the membranes of smooth reticulum are poorly developed and their quantitative changes during the cycle are not significant. Various forms of lysosomes, whose volume reaches its maximum in dioestrus and during pro-oestrus, constitute a constant component of cytoplasm. Secretory granules occur only rarely in these cells. Kinocilia grow from the basal corpuscles and are more frequent on cells with a light cytoplasm. Higher-density cells have more micro-villi between kinocilia. Deciliation with the disintegration of membrane, filaments and often also the basal corpuscles is observed during metoestrus and at the beginning of dioestrus. Reciliation begins with the formation of basal corpuscles and their replication at the end of dioestrus and in pro-oestrus. The frequency of ciliary regeneration is comparatively small.

Flood of May 23, 2004, in the Turkey and Maquoketa River basins, northeast Iowa

USGS Publications Warehouse

Eash, David A.

2006-01-01

Severe flooding occurred on May 23, 2004, in the Turkey River Basin in Clayton County and in the Maquoketa River Basin in Delaware County following intense thunderstorms over northeast Iowa. Rain gages at Postville and Waucoma, Iowa, recorded 72-hour rainfall of 6.32 and 6.55 inches, respectively, on May 23. Unofficial rainfall totals of 8 to 10 inches were reported in the Turkey River Basin. The peak discharge on May 23 at the Turkey River at Garber streamflow-gaging station was 66,700 cubic feet per second (recurrence interval greater than 500 years) and is the largest flood on record in the Turkey River Basin. The timing of flood crests on the Turkey and Volga Rivers, and local tributaries, coincided to produce a record flood on the lower part of the Turkey River. Three large floods have occurred at the Turkey River at Garber gaging station in a 13-year period. Peak discharges of the floods of June 1991 and May 1999 were 49,900 cubic feet per second (recurrence interval about 150 years) and 53,900 cubic feet per second (recurrence interval about 220 years), respectively. The peak discharge on May 23 at the Maquoketa River at Manchester gaging station was 26,000 cubic feet per second (recurrence interval about 100 years) and is the largest known flood in the upper part of the Maquoketa River Basin.

Nutrient sources and transport in the Missouri River Basin, with emphasis on the effects of irrigation and reservoirs

USGS Publications Warehouse

Brown, J.B.; Sprague, L.A.; Dupree, J.A.

2011-01-01

SPAtially Referenced Regressions On Watershed attributes (SPARROW) models were used to relate instream nutrient loads to sources and factors influencing the transport of nutrients in the Missouri River Basin. Agricultural inputs from fertilizer and manure were the largest nutrient sources throughout a large part of the basin, although atmospheric and urban inputs were important sources in some areas. Sediment mobilized from stream channels was a source of phosphorus in medium and larger streams. Irrigation on agricultural land was estimated to decrease the nitrogen load reaching the Mississippi River by as much as 17%, likely as a result of increased anoxia and denitrification in the soil zone. Approximately 16% of the nitrogen load and 33% of the phosphorus load that would have otherwise reached the Mississippi River was retained in reservoirs and lakes throughout the basin. Nearly half of the total attenuation occurred in the eight largest water bodies. Unlike the other major tributary basins, nearly the entire instream nutrient load leaving the outlet of the Platte and Kansas River subbasins reached the Mississippi River. Most of the larger reservoirs and lakes in the Platte River subbasin are upstream of the major sources, whereas in the Kansas River subbasin, most of the source inputs are in the southeast part of the subbasin where characteristics of the area and proximity to the Missouri River facilitate delivery of nutrients to the Mississippi River.

Prolapsing Gastric Polyp Causing Intermittent Gastric Outlet Obstruction.

PubMed

Kosai, Nik Ritza; Gendeh, Hardip Singh; Norfaezan, Abdul Rashid; Razman, Jamin; Sutton, Paul Anthony; Das, Srijit

2015-06-01

Gastric polyps are often an incidental finding on upper gastrointestinal endoscopy, with an incidence up to 5%. The majority of gastric polyps are asymptomatic, occurring secondary to inflammation. Prior reviews discussed Helicobacter pylori (H pylori)-associated singular gastric polyposis; however, we present a rare and unusual case of recurrent multiple benign gastric polyposis post H pylori eradication resulting in intermittent gastric outlet obstruction. A 70-year-old independent male, Chinese in ethnicity, with a background of diabetes mellitus, hypertension, and a simple renal cyst presented with a combination of melena, anemia, and intermittent vomiting of partially digested food after meals. Initial gastroscopy was positive for H pylori; thus he was treated with H pylori eradication and proton pump inhibitors. Serial gastroscopy demonstrated multiple sessile gastric antral polyps, the largest measuring 4 cm. Histopathologic examination confirmed a benign hyperplastic lesion. Computed tomography identified a pyloric mass with absent surrounding infiltration or metastasis. A distal gastrectomy was performed, whereby multiple small pyloric polyps were found, the largest prolapsing into the pyloric opening, thus explaining the intermittent nature of gastric outlet obstruction. Such polyps often develop from gastric ulcers and, if left untreated, may undergo neoplasia to form malignant cells. A distal gastrectomy was an effective choice of treatment, taking into account the polyp size, quantity, and potential for malignancy as opposed to an endoscopic approach, which may not guarantee a complete removal of safer margins and depth. Therefore, surgical excision is favorable for multiple large gastric polyps with risk of malignancy.

Size matters: concurrency and the epidemic potential of HIV in small networks.

PubMed

Carnegie, Nicole Bohme; Morris, Martina

2012-01-01

Generalized heterosexual epidemics are responsible for the largest share of the global burden of HIV. These occur in populations that do not have high rates of partner acquisition, and research suggests that a pattern of fewer, but concurrent, partnerships may be the mechanism that provides the connectivity necessary for sustained transmission. We examine how network size affects the impact of concurrency on network connectivity. We use a stochastic network model to generate a sample of networks, varying the size of the network and the level of concurrency, and compare the largest components for each scenario to the asymptotic expected values. While the threshold for the growth of a giant component does not change, the transition is more gradual in the smaller networks. As a result, low levels of concurrency generate more connectivity in small networks. Generalized HIV epidemics are by definition those that spread to a larger fraction of the population, but the mechanism may rely in part on the dynamics of transmission in a set of linked small networks. Examples include rural populations in sub-Saharan Africa and segregated minority populations in the US, where the effective size of the sexual network may well be in the hundreds, rather than thousands. Connectivity emerges at lower levels of concurrency in smaller networks, but these networks can still be disconnected with small changes in behavior. Concurrency remains a strategic target for HIV combination prevention programs in this context.

Fluctuating micro-heterogeneity in water-tert-butyl alcohol mixtures and lambda-type divergence of the mean cluster size with phase transition-like multiple anomalies

NASA Astrophysics Data System (ADS)

Banerjee, Saikat; Furtado, Jonathan; Bagchi, Biman

2014-05-01

Water-tert-butyl alcohol (TBA) binary mixture exhibits a large number of thermodynamic and dynamic anomalies. These anomalies are observed at surprisingly low TBA mole fraction, with xTBA ≈ 0.03-0.07. We demonstrate here that the origin of the anomalies lies in the local structural changes that occur due to self-aggregation of TBA molecules. We observe a percolation transition of the TBA molecules at xTBA ≈ 0.05. We note that "islands" of TBA clusters form even below this mole fraction, while a large spanning cluster emerges above that mole fraction. At this percolation threshold, we observe a lambda-type divergence in the fluctuation of the size of the largest TBA cluster, reminiscent of a critical point. Alongside, the structure of water is also perturbed, albeit weakly, by the aggregation of TBA molecules. There is a monotonic decrease in the tetrahedral order parameter of water, while the dipole moment correlation shows a weak nonlinearity. Interestingly, water molecules themselves exhibit a reverse percolation transition at higher TBA concentration, xTBA ≈ 0.45, where large spanning water clusters now break-up into small clusters. This is accompanied by significant divergence of the fluctuations in the size of largest water cluster. This second transition gives rise to another set of anomalies around. Both the percolation transitions can be regarded as manifestations of Janus effect at small molecular level.

Fluctuating micro-heterogeneity in water-tert-butyl alcohol mixtures and lambda-type divergence of the mean cluster size with phase transition-like multiple anomalies.

PubMed

Banerjee, Saikat; Furtado, Jonathan; Bagchi, Biman

2014-05-21

Water-tert-butyl alcohol (TBA) binary mixture exhibits a large number of thermodynamic and dynamic anomalies. These anomalies are observed at surprisingly low TBA mole fraction, with x(TBA) ≈ 0.03-0.07. We demonstrate here that the origin of the anomalies lies in the local structural changes that occur due to self-aggregation of TBA molecules. We observe a percolation transition of the TBA molecules at x(TBA) ≈ 0.05. We note that "islands" of TBA clusters form even below this mole fraction, while a large spanning cluster emerges above that mole fraction. At this percolation threshold, we observe a lambda-type divergence in the fluctuation of the size of the largest TBA cluster, reminiscent of a critical point. Alongside, the structure of water is also perturbed, albeit weakly, by the aggregation of TBA molecules. There is a monotonic decrease in the tetrahedral order parameter of water, while the dipole moment correlation shows a weak nonlinearity. Interestingly, water molecules themselves exhibit a reverse percolation transition at higher TBA concentration, x(TBA) ≈ 0.45, where large spanning water clusters now break-up into small clusters. This is accompanied by significant divergence of the fluctuations in the size of largest water cluster. This second transition gives rise to another set of anomalies around. Both the percolation transitions can be regarded as manifestations of Janus effect at small molecular level.

Prolapsing Gastric Polyp Causing Intermittent Gastric Outlet Obstruction

PubMed Central

Kosai, Nik Ritza; Gendeh, Hardip Singh; Norfaezan, Abdul Rashid; Razman, Jamin; Sutton, Paul Anthony; Das, Srijit

2015-01-01

Gastric polyps are often an incidental finding on upper gastrointestinal endoscopy, with an incidence up to 5%. The majority of gastric polyps are asymptomatic, occurring secondary to inflammation. Prior reviews discussed Helicobacter pylori (H pylori)–associated singular gastric polyposis; however, we present a rare and unusual case of recurrent multiple benign gastric polyposis post H pylori eradication resulting in intermittent gastric outlet obstruction. A 70-year-old independent male, Chinese in ethnicity, with a background of diabetes mellitus, hypertension, and a simple renal cyst presented with a combination of melena, anemia, and intermittent vomiting of partially digested food after meals. Initial gastroscopy was positive for H pylori; thus he was treated with H pylori eradication and proton pump inhibitors. Serial gastroscopy demonstrated multiple sessile gastric antral polyps, the largest measuring 4 cm. Histopathologic examination confirmed a benign hyperplastic lesion. Computed tomography identified a pyloric mass with absent surrounding infiltration or metastasis. A distal gastrectomy was performed, whereby multiple small pyloric polyps were found, the largest prolapsing into the pyloric opening, thus explaining the intermittent nature of gastric outlet obstruction. Such polyps often develop from gastric ulcers and, if left untreated, may undergo neoplasia to form malignant cells. A distal gastrectomy was an effective choice of treatment, taking into account the polyp size, quantity, and potential for malignancy as opposed to an endoscopic approach, which may not guarantee a complete removal of safer margins and depth. Therefore, surgical excision is favorable for multiple large gastric polyps with risk of malignancy. PMID:25578789

Nutrient Sources and Transport in the Missouri River Basin, with Emphasis on the Effects of Irrigation and Reservoirs1

PubMed Central

Brown, Juliane B; Sprague, Lori A; Dupree, Jean A

2011-01-01

Abstract SPAtially Referenced Regressions On Watershed attributes (SPARROW) models were used to relate instream nutrient loads to sources and factors influencing the transport of nutrients in the Missouri River Basin. Agricultural inputs from fertilizer and manure were the largest nutrient sources throughout a large part of the basin, although atmospheric and urban inputs were important sources in some areas. Sediment mobilized from stream channels was a source of phosphorus in medium and larger streams. Irrigation on agricultural land was estimated to decrease the nitrogen load reaching the Mississippi River by as much as 17%, likely as a result of increased anoxia and denitrification in the soil zone. Approximately 16% of the nitrogen load and 33% of the phosphorus load that would have otherwise reached the Mississippi River was retained in reservoirs and lakes throughout the basin. Nearly half of the total attenuation occurred in the eight largest water bodies. Unlike the other major tributary basins, nearly the entire instream nutrient load leaving the outlet of the Platte and Kansas River subbasins reached the Mississippi River. Most of the larger reservoirs and lakes in the Platte River subbasin are upstream of the major sources, whereas in the Kansas River subbasin, most of the source inputs are in the southeast part of the subbasin where characteristics of the area and proximity to the Missouri River facilitate delivery of nutrients to the Mississippi River. PMID:22457581

The Great Tumaco, Colombia earthquake of 12 December 1979

USGS Publications Warehouse

Herd, D.G.; Youd, T.L.; Meyer, H.; Arango, C.J.L.; Person, W.J.; Mendoza, C.

1981-01-01

Southwestern Colombia and northern Ecuador were shaken by a shallow-focus earthquake on 12 December 1979. The magnitude 8 shock, located near Tumaco, Colombia, was the largest in northwestern South America since 1942 and had been forecast to fill a seismic gap. Thrust faulting occurred on a 280- by 130-kilometer rectangular patch of a subduction zone that dips east beneath the Pacific coast of Colombia. A 200-kilometer stretch of the coast tectonically subsided as much as 1.6 meters; uplift occurred offshore on the continental slope. A tsunami swept inland immediately after the earthquake. Ground shaking (intensity VI to IX) caused many buildings to collapse and generated liquefaction in sand fills and in Holocene beach, lagoonal, and fluvial deposits.

Preliminary volcano-hazard assessment for Aniakchak Volcano, Alaska

USGS Publications Warehouse

Neal, Christina A.; McGimsey, Robert G.; Miller, Thomas P.; Riehle, James R.; Waythomas, Christopher F.

2000-01-01

Aniakchak is an active volcano located on the Alaska Peninsula 670 kilometers southwest of Anchorage. The volcano consists of a dramatic, 10-kilometer-diameter, 0.5 to 1.0-kilometer-deep caldera that formed during a catastrophic eruption 3,500 years ago. Since then, at least a dozen separate vents within the caldera have erupted, often explosively, to produce lava flows and widespread tephra (ash) deposits. The most recent eruption at Aniakchak occurred in 1931 and was one of the largest explosive eruptions in Alaska in the last 100 years. Although Aniakchak volcano presently shows no signs of unrest, explosive and nonexplosive eruptions will occur in the future. Awareness of the hazards posed by future eruptions is a key factor in minimizing impact.

Strong earthquakes, novae and cosmic ray environment

NASA Technical Reports Server (NTRS)

Yu, Z. D.

1985-01-01

Observations about the relationship between seismic activity and astronomical phenomena are discussed. First, after investigating the seismic data (magnitude 7.0 and over) with the method of superposed epochs it is found that world seismicity evidently increased after the occurring of novae with apparent magnitude brighter than 2.2. Second, a great many earthquakes of magnitude 7.0 and over occurred in the 13th month after two of the largest ground level solar cosmic ray events (GLEs). The causes of three high level phenomena of global seismic activity in 1918-1965 can be related to these, and it is suggested that according to the information of large GLE or bright nova predictions of the times of global intense seismic activity can be made.

A seismic gap along an accreting plate boundary : Example of the Djibouti Ridge, Afar, East Africa

NASA Astrophysics Data System (ADS)

Ruegg, Jean-Claude; Lépine, Jean-Claude

1983-05-01

A segment of the Gulf of Tadjoura (Djibouti, East-Africa) accreting plate boundary, shows a period of quiescence in the seismic activity since 1974. This segment corresponds to the extension area of the aftershock activity that has occured after a cluster of magnitude 5.5 earthquakes in April 1973. From this example we propose that the seismic gap concept can be extended to moderate earthquakes occuring at extensional plate boundaries. The magnitude of the largest earthquakes at the spreading axis is limited by the size of the rupture length and by the strength of the brittle lithosphere. In the case of the Djibouti ridge recurrence time of 10-20 years are found for earthquakes of about M =6.

The occurence of uric acids and the growth morphology of the anhydrous monoclinic modification : C 5H 4N 4O 3

NASA Astrophysics Data System (ADS)

Rinaudo, C.; Boistelle, R.

1980-07-01

Anhydrous and hydrated uric acid crystals which frequently occur in human urolithiasis have been grown from pure aqueous solutions at 25 and 37°C. The appearance domain of either modification is given as a function of initial uric acid concentration at pH values ranging from 3.0 to 5.5. The present paper mostly deals with the anhydrous phase and it is shown that its experimental and theoretical growth morphologies are in agreement, the crystals exhibiting the {100}, {210}, {121}, {001} and {201} forms. Crystal habit depends on supersaturation; {100} has always the largest extension at low supersaturation {121} develops to the detriment of {210}, {001} and {201}.

Exercise mitigates cumulative associations between stress and BMI in girls age 10 to 19.

PubMed

Puterman, Eli; Prather, Aric A; Epel, Elissa S; Loharuka, Sheila; Adler, Nancy E; Laraia, Barbara; Tomiyama, A Janet

2016-02-01

Long-term psychological stress is associated with BMI increases in children as they transition to adulthood, whereas long-term maintenance of physical activity can slow excess weight gain. We hypothesized that in addition to these main effects, long-term physical activity mitigates the relationship between long-term stress and BMI increase. The NHLBI Growth and Health Study enrolled 2,379 10-year-old Black and White girls, following them annually for 10 measurement points. Growth curve modeling captured the dynamics of BMI, measured yearly, and stress and physical activity, measured at varying years. At average levels of activity and stress, with all covariates remaining fixed, average BMI at baseline was 19.74 (SE = 0.38) and increased 0.64 BMI (SE = 0.01, p < .001) units every year. However, this increase in BMI significantly varied as a function of cumulative stress and physical activity. Slower BMI gain occurred in those girls who were less stressed and more active (0.62 BMI units/year, SE = .02, p < .001), whereas the most rapid and largest growth occurred in girls who were more stressed and less active (0.92 BMI units/year, SE = .02, p < .001). Racial identification did not alter these effects. As hypothesized, in girls who maintained long-term activity, BMI growth was mitigated, even when reporting high long-term stress, compared with less physically active girls. This study adds to a converging literature in which physical activity, a modifiable prevention target, functions to potentially limit the damaging health effects of long-term psychological stress. (c) 2016 APA, all rights reserved).

Exercise mitigates cumulative associations between stress and BMI in girls age 10–19

PubMed Central

Prather, Aric A.; Epel, Elissa S.; Loharuka, Sheila; Adler, Nancy E.; Laraia, Barbara

2015-01-01

Objective Long-term psychological stress is associated with BMI increases in children as they transition to adulthood, while long-term maintenance of physical activity can slow excess weight gain. We hypothesized that in addition to these main effects, long-term physical activity mitigates the relationship between long-term stress and BMI increase. Methods The NHLBI Growth and Health Study enrolled 2,379 10-year-old Black and White girls, following them annually for 10 measurement points. Growth curve modeling captured the dynamics of BMI, measured yearly, and stress and physical activity, measured every other year. Results At average levels of activity and stress, with all covariates remaining fixed, average BMI at baseline was 19.74 (SE = 0.38) and increased 0.64 BMI (SE= 0.01, p < .001) units every year. However, this increase in BMI significantly varied as a function of cumulative stress and physical activity. Slower BMI gain occurred in those girls who were less stressed and more active (0.62 BMI units/year, SE= .02, p < .001), whereas the most rapid and largest growth occurred in girls who were the more stressed and less active (0.92 BMI units/year, SE= .02, p < .001). Racial identification did not alter these effects. Conclusions As hypothesized, in girls who maintained long-term activity, BMI growth was mitigated, even when reporting high long-term stress, compared to less physically active girls. This study adds to a converging literature in which physical activity, a modifiable prevention target, functions to potentially limit the damaging health effects of long-term psychological stress. PMID:26301595

Effects of turbulence-induced collision enhancement on heavy precipitation: The 21 September 2010 case over the Korean Peninsula

NASA Astrophysics Data System (ADS)

Lee, Hyunho; Baik, Jong-Jin

2016-10-01

The effects of turbulence-induced collision enhancement (TICE) on a heavy precipitation event that occurred on 21 September 2010 over the middle Korean Peninsula are examined. For this purpose, an updated bin microphysics scheme incorporating TICE for drop-drop and drop-graupel collisions is implemented into the Weather Research and Forecasting (WRF) model. The numerical simulation shows some differences in the strong precipitation system compared to the observations but generally captures well the important features of observed synoptic conditions, surface precipitation, and radar reflectivity. While the change in domain-averaged surface precipitation amount due to TICE is small and similar to that due to small initial perturbations, the spatial distribution of surface precipitation amount is somewhat altered due to TICE. The surface precipitation amount is increased due to TICE in the area where the largest surface precipitation occurred, but the effects of different flow realizations also contribute to the changes. TICE accelerates the coalescence between small cloud droplets, which induces a decrease in condensation and an increase in excess water vapor transported upward. This causes an increase in relative humidity with respect to ice at high altitudes, hence increasing the depositional growth of ice particles. Therefore, the ice mass increases due to TICE, and this increase induces the increases in riming and melting of ice particles. A series of these microphysical changes due to TICE are regarded as partially contributing to the increase in surface precipitation amount in some areas, hence inducing alterations in the spatial distribution of surface precipitation amount.

Cortical and Subcortical Brain Morphometry Differences Between Patients With Autism Spectrum Disorder and Healthy Individuals Across the Lifespan: Results From the ENIGMA ASD Working Group.

PubMed

van Rooij, Daan; Anagnostou, Evdokia; Arango, Celso; Auzias, Guillaume; Behrmann, Marlene; Busatto, Geraldo F; Calderoni, Sara; Daly, Eileen; Deruelle, Christine; Di Martino, Adriana; Dinstein, Ilan; Duran, Fabio Luis Souza; Durston, Sarah; Ecker, Christine; Fair, Damien; Fedor, Jennifer; Fitzgerald, Jackie; Freitag, Christine M; Gallagher, Louise; Gori, Ilaria; Haar, Shlomi; Hoekstra, Liesbeth; Jahanshad, Neda; Jalbrzikowski, Maria; Janssen, Joost; Lerch, Jason; Luna, Beatriz; Martinho, Mauricio Moller; McGrath, Jane; Muratori, Filippo; Murphy, Clodagh M; Murphy, Declan G M; O'Hearn, Kirsten; Oranje, Bob; Parellada, Mara; Retico, Alessandra; Rosa, Pedro; Rubia, Katya; Shook, Devon; Taylor, Margot; Thompson, Paul M; Tosetti, Michela; Wallace, Gregory L; Zhou, Fengfeng; Buitelaar, Jan K

2018-04-01

Neuroimaging studies show structural differences in both cortical and subcortical brain regions in children and adults with autism spectrum disorder (ASD) compared with healthy subjects. Findings are inconsistent, however, and it is unclear how differences develop across the lifespan. The authors investigated brain morphometry differences between individuals with ASD and healthy subjects, cross-sectionally across the lifespan, in a large multinational sample from the Enhancing Neuroimaging Genetics Through Meta-Analysis (ENIGMA) ASD working group. The sample comprised 1,571 patients with ASD and 1,651 healthy control subjects (age range, 2-64 years) from 49 participating sites. MRI scans were preprocessed at individual sites with a harmonized protocol based on a validated automated-segmentation software program. Mega-analyses were used to test for case-control differences in subcortical volumes, cortical thickness, and surface area. Development of brain morphometry over the lifespan was modeled using a fractional polynomial approach. The case-control mega-analysis demonstrated that ASD was associated with smaller subcortical volumes of the pallidum, putamen, amygdala, and nucleus accumbens (effect sizes [Cohen's d], 0.13 to -0.13), as well as increased cortical thickness in the frontal cortex and decreased thickness in the temporal cortex (effect sizes, -0.21 to 0.20). Analyses of age effects indicate that the development of cortical thickness is altered in ASD, with the largest differences occurring around adolescence. No age-by-ASD interactions were observed in the subcortical partitions. The ENIGMA ASD working group provides the largest study of brain morphometry differences in ASD to date, using a well-established, validated, publicly available analysis pipeline. ASD patients showed altered morphometry in the cognitive and affective parts of the striatum, frontal cortex, and temporal cortex. Complex developmental trajectories were observed for the different regions, with a developmental peak around adolescence. These findings suggest an interplay in the abnormal development of the striatal, frontal, and temporal regions in ASD across the lifespan.

Relative impact of emissions controls and meteorology on air pollution mitigation associated with the Asia-Pacific Economic Cooperation (APEC) conference in Beijing, China.

PubMed

Wang, Yuqin; Zhang, Yang; Schauer, James Jay; de Foy, Benjamin; Guo, Bo; Zhang, Yuanxun

2016-11-15

The Beijing government and its surrounding provinces implemented a series of measures to ensure haze-free skies during the 22(nd) Asia-Pacific Economic Cooperation (APEC) conference (November 10(th)-11(th), 2014). These measures included restrictions on traffic, construction, and industrial activity. Twelve hour measurements of the concentration and composition of ambient fine particulate matter (PM2.5) were performed for 5 consecutive months near the APEC conference site before (September 11(th)-November 2(nd), 2014), during (November 3(rd)-12(th), 2014) and after (November 13(th), 2014-January 31(st), 2015). The measurements are used in a positive matrix factorization model to determine the contributions from seven sources of PM2.5: secondary aerosols, traffic exhaust, industrial emission, road dust, soil dust, biomass burning and residual oil combustion. The source apportionment results are integrated with backward trajectory analysis using Weather Research and Forecast (WRF) meteorological simulations, which determine the relative influence of new regulation and meteorology upon improved air quality during the APEC conference. Data show that controls are very effective, but meteorology must be taken into account to determine the actual influence of the controls on pollution reduction. The industry source control is the most effective for reducing concentrations, followed by secondary aerosol and biomass controls, while the least effective control is for the residual oil combustion source. The largest reductions in concentrations occur when air mass transport is from the west-northwest (Ulanqab). Secondary aerosol and traffic exhaust reductions are most significant for air mass transport from the north-northwest (Xilingele League) origin, and least significant for northeast transport (Chifeng via Tangshan conditions). The largest reductions of soil dust, biomass burning, and industrial source are distinctly seen for Ulanqab conditions and least distinct for Xilingele League. Copyright © 2016 Elsevier B.V. All rights reserved.

Relative Impact of Emissions Controls and Meteorology on Air Pollution Mitigation Associated with the Asia-Pacific Economic Cooperation (APEC) Conference in Beijing, China

NASA Astrophysics Data System (ADS)

Zhang, Y.; Wang, Y.; Schauer, J. J.; de Foy, B.

2016-12-01

The Beijing government and its surrounding provinces implemented a series of measures to ensure haze-free skies during the 22nd Asia-Pacific Economic Cooperation (APEC) conference (November 10th - 11th, 2014). These measures included restrictions on traffic, construction, and industrial activity. Twelve hour measurements of the concentration and composition of ambient fine particulate matter (PM2.5) were performed for 5 consecutive months near the APEC conference site before (September 11th - November 2nd, 2014), during (November 3rd - 12th, 2014) and after (November 13th, 2014 - January 31st, 2015). The measurements are used in a positive matrix factorization model to determine the contributions from seven sources of PM2.5: secondary aerosols, mobile source, industrial emission, road dust, soil dust, biomass burning and residual oil combustion. The source apportionment results are integrated with backward trajectory analysis using Weather Research and Forecast (WRF) meteorological simulations, which determine the relative influence of new regulation and meteorology upon improved air quality during the APEC conference. Data show that controls are very effective, but meteorology must be taken into account to determine the actual influence of the controls on pollution reduction. The Industry source control is the most effective for reducing concentrations, follows by secondary aerosol and biomass controls, while the least effective control is for the residual oil combustion source. The largest reductions in concentrations occur when air mass transport is from the west-northwest (Ulanqab). Secondary aerosol and mobile source reductions are most significant for air mass transport from the north-northwest (Xilingele League) origin, and least significant for northeast transport (Chifeng via Tangshan conditions). The largest reductions of soil dust, biomass burning, and industrial source are distinctly seen for Ulanqab conditions and least distinct for Xilingele League.

Clear-Sky UV-B trends over Northern Midlatitudes derived from TOMS Low-Reflectivity Footprint Measurements

NASA Technical Reports Server (NTRS)

Ziemke, Jerry; Chandra, Sushil; Varotsos, C.

1998-01-01

This study investigates the distribution of clear-sky ultraviolet-B (UV-B, wavelengths 290-320 nm) trends in northern midlatitudes using 1979-1991 Nimbus 7 total ozone mapping spectrometer (TOMS) version 7 low-reflectivity (R<0.2) total ozone footprint measurements. The incorporation of essentially cloud-free ozone data from TOMS provides a direct method for separating transient cloud effects from anthropogenic and other dynamical factors present in UV-B. This study has also included both National Oceanic and Atmospheric Administration (NOAA) microwave sounding unit channel 4 (MSU4) and National Centers for Environmental Prediction (NCEP) 500 hPa temperature (T500) fields in our trend models to improve UV-Index (UVI) trend statistics and to investigate the effects of interannual changes in UVI caused by synoptic-scale (horizontal wavelengths 4000-8000 km) and planetary-scale (horizontal wavelengths greater than 8000 km) dynamical events. Clear-sky UVI trends in the northern midlatitudes show large increases (exceeding 10 % per decade) and distinct regional variability especially during winter-spring months which can be attributed to topography and dynamical forcing effects. In the UV-important summer-autumn months, these trends are more uniformly distributed and still statistically significant, although smaller at around +2 to +3 % per decade. Specifically, during April largest increases in midlatitude UVI are seen to extend from near the dateline eastward across North America. In June months largest UVI increases occur over the east Asian continent with values around +5 to +6 % per decade. These increases in UVI over both the Pacific and Asian continent regions persist through summer into Autumn. In the the European sector, statistically significant increases in clear-sky UVI are found over central Europe with values around +2 to +3 % per decade and +8 to +9 % per decade during summer and winter-spring months, respectively. Over the nearby Mediterranean region these seasonal trends are around +2 to +3 and +5 to +6 % per decade.

The impact of future sea-level rise on the global tides

NASA Astrophysics Data System (ADS)

Pickering, M. D.; Horsburgh, K. J.; Blundell, J. R.; Hirschi, J. J.-M.; Nicholls, R. J.; Verlaan, M.; Wells, N. C.

2017-06-01

Tides are a key component in coastal extreme water levels. Possible changes in the tides caused by mean sea-level rise (SLR) are therefore of importance in the analysis of coastal flooding, as well as many other applications. We investigate the effect of future SLR on the tides globally using a fully global forward tidal model: OTISmpi. Statistical comparisons of the modelled and observed tidal solutions demonstrate the skill of the refined model setup with no reliance on data assimilation. We simulate the response of the four primary tidal constituents to various SLR scenarios. Particular attention is paid to future changes at the largest 136 coastal cities, where changes in water level would have the greatest impact. Spatially uniform SLR scenarios ranging from 0.5 to 10 m with fixed coastlines show that the tidal amplitudes in shelf seas globally respond strongly to SLR with spatially coherent areas of increase and decrease. Changes in the M2 and S2 constituents occur globally in most shelf seas, whereas changes in K1 and O1 are confined to Asian shelves. With higher SLR tidal changes are often not proportional to the SLR imposed and larger portions of mean high water (MHW) changes are above proportional. Changes in MHW exceed ±10% of the SLR at 10% of coastal cities. SLR scenarios allowing for coastal recession tend increasingly to result in a reduction in tidal range. The fact that the fixed and recession shoreline scenarios result mainly in changes of opposing sign is explained by the effect of the perturbations on the natural period of oscillation of the basin. Our results suggest that coastal management strategies could influence the sign of the tidal amplitude change. The effect of a spatially varying SLR, in this case fingerprints of the initial elastic response to ice mass loss, modestly alters the tidal response with the largest differences at high latitudes.

Metal contamination and post-remediation recovery in the Boulder River watershed, Jefferson County, Montana

USGS Publications Warehouse

Unruh, Daniel M.; Church, Stanley E; Nimick, David A.; Fey, David L.

2009-01-01

The legacy of acid mine drainage and toxic trace metals left in streams by historical mining is being addressed by many important yet costly remediation efforts. Monitoring of environmental conditions frequently is not performed but is essential to evaluate remediation effectiveness, determine whether clean-up goals have been met, and assess which remediation strategies are most effective. Extensive pre- and post-remediation data for water and sediment quality for the Boulder River watershed in southwestern Montana provide an unusual opportunity to demonstrate the importance of monitoring. The most extensive restoration in the watershed occurred at the Comet mine on High Ore Creek and resulted in the most dramatic improvement in aquatic habitat. Removal of contaminated sediment and tailings, and stream-channel reconstruction reduced Cd and Zn concentrations in water such that fish are now present, and reduced metal concentrations in streambed sediment by a factor of c. 10, the largest improvement in the district. Waste removals at the Buckeye/Enterprise and Bullion mine sites produced limited or no improvement in water and sediment quality, and acidic drainage from mine adits continues to degrade stream aquatic habitat. Recontouring of hillslopes that had funnelled runoff into the workings of the Crystal mine substantially reduced metal concentrations in Uncle Sam Gulch, but did not eliminate all of the acidic adit drainage. Lead isotopic evidence suggests that the Crystal mine rather than the Comet mine is now the largest source of metals in streambed sediment of the Boulder River. The completed removal actions prevent additional contaminants from entering the stream, but it may take many years for erosional processes to diminish the effects of contaminated sediment already in streams. Although significant strides have been made, additional efforts to seal draining adits or treat the adit effluent at the Bullion and Crystal mines would need to be completed to achieve the desired restoration.

Surface Temperature and Precipitation Affecting GPS Signals Before the 2009 L'Aquila Earthquake (Central Italy).

NASA Astrophysics Data System (ADS)

Crescentini, L.; Amoruso, A.; Chiaraluce, L.

2017-12-01

This work focuses on GPS time series recorded before the Mw 6.1 earthquake which struck Central Italy in April 2009. It shows how environmental noise effects may be subtle and relevant when investigating relatively small strain signals and how the availability of data from weather stations and water level sensors co-located with GPS stations may provide critical information which must be taken into consideration while dealing with deformation signals.The preparatory phase of a large earthquake may include both seismic (foreshocks) and aseismic (slow slip event, SSE) deforming episodes but, unlike afterslip, no slow event has yet been recorded before moderate earthquakes, even when they occurred close to high-sensitivity strain meters. An exception to this seems to be represented by the 2009 earthquake. The main shock was preceded by a foreshock sequence lasting 6 months; it has been claimed that an analysis of continuous GPS data shows that during the foreshock sequence a 5.9 Mw SSE occurred along a decollement located beneath the reactivated normal fault system. This hypothesized SSE, that started in the middle of February 2009 and lasted for almost two weeks, would have eventually loaded the largest foreshock and the main shock.We show that the strain signal that the SSE would have generated at two laser strainmeters operating at about 20 km NE from the SSE source was essentially undetected. On the contrary, a transient signal is present in temperature and precipitation time series recorded close to the GPS station, MTTO, that has largest signal referred to the SSE, implying that these contaminated the GPS record. This interpretation is corroborated by the strong similarity, during the coldest winter months, between the displacement data of MTTO and a linear combination of filtered temperature and precipitation data, mimicking simple heat conduction and snow accumulation/removal processes. Such a correlation between displacement and environmental data is missing during the other seasons, when it neither snows nor freezes. This lack of correlation seems to exclude simple thermal expansion of the bedrock or the pillar monument itself as a local source of deformation. We hypothesize that thermal effects might be caused by ground freezing and consequent water expansion (about 9%) when liquid water is converted into ice.

Effect of forms of selenium on the accumulation of selenium, sulfur, and forms of nitrogen and phosphorus in forage cowpea (Vigna sinensis)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Singh, M.; Singh, N.

1979-05-01

The effects of forms of selenium on the accumulation of sulfur, selenium, and forms of nitrogen and phosphorus in cowpea (Vigna sinensis) were studied in pots in the greenhouse at Haryana Agricultural University, Hissar, India. The soil used was sandy, and forms of selenium added were Na/sub 2/SeO/sub 4/ 10H/sub 2/O, Na/sub 2/SeO/sub 3/ 5H/sub 2/O, H/sub 2/SeO/sub 3/, and elemental selenium at the rate of 0, 1, 2.5 and 5 ppM. Dry matter yield and sulfur content decreased with increased selenium application. This inhibition in plants, attributable to applied selenium, was in the order SeO/sub 4/ > H/sub 2/SeO/submore » 3/ > SeO/sub 3/ > elemental selenium. Plant selenium increased with increasing application of all forms of selenium. The highest plant selenium (11.58 ppM) was in the plants treated with SeO/sub 4/, followed by the plants treated with H/sub 2/SeO/sub 3/, SeO/sub 3/, and elemental selenium. The total plant phosphorus increased with increased selenium application in any form, but maximum phosphorus occurred in SeO/sub 3/-treated plants. The inorganic phosphorus increased similarly, the largest amount occurring in SeO/sub 4/-treated plants. Organic phosphorus decreased with selenium application; minimum concentration was recorded in SeO/sub 4/-treated plants. Soluble nitrogen decreased, relative to the control, with applications of 2.5 and 5 ppM selenium. This decrease was minimal for elemental selenium and maximum for SeO/sub 4/. Soluble nitrogen, in the case of SeO/sub 3/ was higher than for H/sub 2/SeO/sub 3/. Total plant nitrogen and protein also decreased. Amino N, amide N, and ammoniacal and nitrate N increased, compared to the control. The largest amount of all these forms was noted in SeO/sub 4/-treated plants. Overall, among the forms of selenium normally reported in soils, the SeO/sub 4/ form showed the highest inhibition, whereas SeO/sub 3/ showed less than both SeO/sub 4/ and H/sub 2/SeO/sub 3/.« less

Genetic Population Structure in the Antarctic Benthos: Insights from the Widespread Amphipod, Orchomenella franklini

PubMed Central

Baird, Helena Phoenix; Miller, Karen Joy; Stark, Jonathan Sean

2012-01-01

Currently there is very limited understanding of genetic population structure in the Antarctic benthos. We conducted one of the first studies of microsatellite variation in an Antarctic benthic invertebrate, using the ubiquitous amphipod Orchomenella franklini (Walker, 1903). Seven microsatellite loci were used to assess genetic structure on three spatial scales: sites (100 s of metres), locations (1–10 kilometres) and regions (1000 s of kilometres) sampled in East Antarctica at Casey and Davis stations. Considerable genetic diversity was revealed, which varied between the two regions and also between polluted and unpolluted sites. Genetic differentiation among all populations was highly significant (F ST = 0.086, R ST = 0.139, p<0.001) consistent with the brooding mode of development in O. franklini. Hierarchical AMOVA revealed that the majority of the genetic subdivision occurred across the largest geographical scale, with Nem≈1 suggesting insufficient gene flow to prevent independent evolution of the two regions, i.e., Casey and Davis are effectively isolated. Isolation by distance was detected at smaller scales and indicates that gene flow in O. franklini occurs primarily through stepping-stone dispersal. Three of the microsatellite loci showed signs of selection, providing evidence that localised adaptation may occur within the Antarctic benthos. These results provide insights into processes of speciation in Antarctic brooders, and will help inform the design of spatial management initiatives recently endorsed for the Antarctic benthos. PMID:22479613

QBO/solar modulation of the boreal winter Madden-Julian oscillation: A prediction for the coming solar minimum

NASA Astrophysics Data System (ADS)

Hood, Lon L.

2017-04-01

The Madden-Julian oscillation (MJO), also known as the 30-60 day oscillation, is the strongest of the intraseasonal climate oscillations in the tropics and has significant derivative effects on extratropical circulation and intraseasonal climate. It has recently been shown that the stratospheric quasi-biennial oscillation (QBO) modulates the amplitude of the boreal winter MJO such that MJO amplitudes are larger on average during the easterly phase (QBOE) than during the westerly phase (QBOW). A major possible mechanism is the decrease in static stability in the lowermost stratosphere under QBOE conditions resulting from relative upwelling associated with the QBO-induced meridional circulation. Here evidence is presented that tropical upwelling changes related to the 11 year solar cycle also modulate the boreal winter MJO. Based on 37.3 years of MJO amplitude data, the largest amplitudes and occurrence rates, and the weakest static stabilities in the tropical lower stratosphere, occur during the QBOE phase under solar minimum (SMIN) conditions while the smallest amplitudes and strongest static stabilities occur during the QBOW phase under solar maximum (SMAX) conditions. Conversely, when the QBO and solar forcings are opposed (QBOW/SMIN and QBOE/SMAX), the difference in occurrence rates becomes statistically insignificant. During the coming solar minimum, at least one additional winter in the QBOE/SMIN category should occur (possibly as early as 2017/2018) during which especially large MJO amplitudes are expected and an initial test of these results will be possible.

Relating Topological Determinants of Complex Networks to Their Spectral Properties: Structural and Dynamical Effects

NASA Astrophysics Data System (ADS)

Castellano, Claudio; Pastor-Satorras, Romualdo

2017-10-01

The largest eigenvalue of a network's adjacency matrix and its associated principal eigenvector are key elements for determining the topological structure and the properties of dynamical processes mediated by it. We present a physically grounded expression relating the value of the largest eigenvalue of a given network to the largest eigenvalue of two network subgraphs, considered as isolated: the hub with its immediate neighbors and the densely connected set of nodes with maximum K -core index. We validate this formula by showing that it predicts, with good accuracy, the largest eigenvalue of a large set of synthetic and real-world topologies. We also present evidence of the consequences of these findings for broad classes of dynamics taking place on the networks. As a by-product, we reveal that the spectral properties of heterogeneous networks built according to the linear preferential attachment model are qualitatively different from those of their static counterparts.

Prioritising the placement of riparian vegetation to reduce flood risk and end-of-catchment sediment yields: Important considerations in hydrologically-variable regions.

PubMed

Croke, Jacky; Thompson, Chris; Fryirs, Kirstie

2017-04-01

In perennial stream settings, there is abundant literature confirming that riparian vegetation affects flood hydrology by attenuating the flood wave, enhancing deposition and reducing bank erosion. In contrast, relatively little is known about the effectiveness of riparian vegetation during floods in hydrologically-variable regions. The dominant channel form in these settings is often referred to as a 'macrochannel' or compound channel-in-channel which displays multiple inundation surfaces where it is often difficult to identify the active channel bank and bank top. This study uses the inundation pattern of recent flood events in the Lockyer Valley of South East Queensland (SEQ), Australia to present a framework which specifically considers the interaction between inundation frequency and trapping potential on a range of inundation surfaces. Using hydrological modelling and a consistent definition of floodplains and within-channel features, it outlines five key priority areas for the placement of riparian vegetation to alleviate common flood problems within the catchment. The highest priority for the placement of riparian vegetation to ameliorate the effects of small-moderate floods is on within-channel benches. For out-of-macrochannel flows, riparian vegetation is most effective on genetic floodplains which occupy the largest spatial extent within the valley. In particular, it identifies the need for, and benefits of, revegetation in spill out zones (SOZ) which occur where upstream channel capacity is larger and flow is funnelled at high velocity onto the floodplain downstream. This study highlights the importance of understanding the key geomorphic processes occurring within a catchment and developing effective catchment management plans to suit these conditions. Copyright © 2016 Elsevier Ltd. All rights reserved.

Bromine release during Plinian eruptions along the Central American Volcanic Arc

NASA Astrophysics Data System (ADS)

Hansteen, T. H.; Kutterolf, S.; Appel, K.; Freundt, A.; Perez-Fernandez, W.; Wehrmann, H.

2010-12-01

Volcanoes of the Central American Volcanic Arc (CAVA) have produced at least 72 highly explosive eruptions within the last 200 ka. The eruption columns of all these “Plinian” eruptions reached well into the stratosphere such that their released volatiles may have influenced atmospheric chemistry and climate. While previous research has focussed on the sulfur and chlorine emissions during such large eruptions, we here present measurements of the heavy halogen bromine by means of synchrotron radiation induced micro-XRF microanalysis (SR-XRF) with typical detection limits at 0.3 ppm (in Fe rich standard basalt ML3B glass). Spot analyses of pre-eruptive glass inclusions trapped in minerals formed in magma reservoirs were compared with those in matrix glasses of the tephras, which represent the post-eruptive, degassed concentrations. The concentration difference between inclusions and matrix glasses, multiplied by erupted magma mass determined by extensive field mapping, yields estimates of the degassed mass of bromine. Br is probably hundreds of times more effective in destroying ozone than Cl, and can accumulate in the stratosphere over significant time scales. Melt inclusions representing deposits of 22 large eruptions along the CAVA have Br contents between 0.5 and 13 ppm. Br concentrations in matrix glasses are nearly constant at 0.4 to 1.5 ppm. However, Br concentrations and Cl/Br ratios vary along the CAVA. The highest values of Br contents (>8 ppm) and lowest Cl/Br ratios (170 to 600) in melt inclusions occur across central Nicaragua and southern El Salvador, and correlate with bulk-rock compositions of high Ba/La > 85 as well as low La/Yb <5. Thus we observe the maximum magmatic Br-concentrations in the segements of the arc. where the input of sediment and water into the subduction system is largest and the melting column is longest. The largest eruptive emissions of Br into the atmosphere, however, occurred in Guatemala due to the large magnitude of eruptions. The most prominent example is the 84 ka Los Chocoyos eruption from Atitlán Caldera, which discharged 700 kilotons of Br. On average, each of the remaining 21 CAVA eruptions studied have discharged c.100 kilotons of bromine. During the past 200 ka, CAVA volcanoes have emitted a cumulative mass of 3.2 Mt of Br through highly explosive eruptions. There are six periods in the past (c. 2ka, 6ka, 25ka, 40ka, 60ka, 75ka) when up to four larger eruptions occurred within only several hundred years. The heavy halogen release of these eruptions may have had a cumulative effect on the atmosphere which is presently investigated by climate/atmosphere models based on our analyses as input data.

[Preliminary analysis on relationship between traditional efficacy of Chinese medicine and modern pharmacological action].

PubMed

Ren, Jun-Guo; Wang, Dong-Zhi; Lei, Lei; Kang, Li; Liu, Jian-Xun

2017-05-01

To find the relationship between traditional efficacy of Chinese medicine and modern pharmacological action by using data mining, and provide information and reference for further research and development for the pharmacology research of traditional Chinese medicine.The information of 547 kinds of traditional Chinese medicines, 335 kinds of Chinese medicine effects and 86 kinds of pharmacological actions were collected and processed in Clinical Guide to the Chinese Pharmacopoeia published in 2010; Access and Excel software were used to analyze the frequence and frequency of single effect, pharmacological action, and both. In addition, the relationship between efficacy and pharmacology was analyzed with the clearing heat and antibacterial effects as the example. The analysis results showed that 547 kinds of Chinese medicines involved 335 kinds of Chinese medicine effects and 86 kinds of pharmacological actions. Among them, the most frequent Chinese medicine effect was"clearing heat", whose frequence was 130 and the frequency was 0.24; the most frequent pharmacological action was "anti-inflammatory action" whose frequence was 191 and the frequency was 0.35. The most common efficacy-pharmacological action group was "clearing heat" and "anti-bacterial action", whose frequence was 75 and the frequency was 0.26. The couple of "purgation" and "cathartic effect" had the largest frequency of 0.30, but they just appeared together for 3 times. There were 52 kinds of pharmacological actions that occurred together with clearing heat, of which, the top 10 were anti-bacterial action, anti-inflammatory action, antineoplastic action, anti-hepatic injury action, immunoregulation action, antipyretic action, antiviralaction, hypoglycemic action, antioxidant action and analgesic action. There were 161 kinds of Chinese medicine effects that occurred together with anti-bacterial action, of which, the top 10 were clearing heat, detoxification, detumescence, analgesia, resolving dampness, pesticide, cooling blood, expelling wind, eliminating dampness and hemostasis. These results suggested that there was a certain relationship between traditional Chinese medicine effects and modern pharmacological actions. Copyright© by the Chinese Pharmaceutical Association.

Genome of Phaeocystis globosa virus PgV-16T highlights the common ancestry of the largest known DNA viruses infecting eukaryotes

PubMed Central

Santini, Sebastien; Jeudy, Sandra; Bartoli, Julia; Poirot, Olivier; Lescot, Magali; Abergel, Chantal; Barbe, Valérie; Wommack, K. Eric; Noordeloos, Anna A. M.; Brussaard, Corina P. D.; Claverie, Jean-Michel

2013-01-01

Large dsDNA viruses are involved in the population control of many globally distributed species of eukaryotic phytoplankton and have a prominent role in bloom termination. The genus Phaeocystis (Haptophyta, Prymnesiophyceae) includes several high-biomass-forming phytoplankton species, such as Phaeocystis globosa, the blooms of which occur mostly in the coastal zone of the North Atlantic and the North Sea. Here, we report the 459,984-bp-long genome sequence of P. globosa virus strain PgV-16T, encoding 434 proteins and eight tRNAs and, thus, the largest fully sequenced genome to date among viruses infecting algae. Surprisingly, PgV-16T exhibits no phylogenetic affinity with other viruses infecting microalgae (e.g., phycodnaviruses), including those infecting Emiliania huxleyi, another ubiquitous bloom-forming haptophyte. Rather, PgV-16T belongs to an emerging clade (the Megaviridae) clustering the viruses endowed with the largest known genomes, including Megavirus, Mimivirus (both infecting acanthamoeba), and a virus infecting the marine microflagellate grazer Cafeteria roenbergensis. Seventy-five percent of the best matches of PgV-16T–predicted proteins correspond to two viruses [Organic Lake phycodnavirus (OLPV)1 and OLPV2] from a hypersaline lake in Antarctica (Organic Lake), the hosts of which are unknown. As for OLPVs and other Megaviridae, the PgV-16T sequence data revealed the presence of a virophage-like genome. However, no virophage particle was detected in infected P. globosa cultures. The presence of many genes found only in Megaviridae in its genome and the presence of an associated virophage strongly suggest that PgV-16T shares a common ancestry with the largest known dsDNA viruses, the host range of which already encompasses the earliest diverging branches of domain Eukarya. PMID:23754393

A research program to reduce interior noise in general aviation airplanes. Influence of depressurization and damping material on the noise reduction characteristics of flat and curved stiffened panels

NASA Technical Reports Server (NTRS)

Navaneethan, R.; Streeter, B.; Koontz, S.; Roskam, J.

1981-01-01

Some 20 x 20 aluminum panels were studied in a frequency range from 20 Hz to 5000 Hz. The noise sources used were a swept sine wave generator and a random noise generator. The effect of noise source was found to be negligible. Increasing the pressure differential across the panel gave better noise reduction below the fundamental resonance frequency due to an increase in stiffness. The largest increase occurred in the first 1 psi pressure differential. The curved, stiffened panel exhibited similar behavior, but with a lower increase of low frequency noise reduction. Depressurization on these panels resulted in decreased noise reduction at higher frequencies. The effect of damping tapes on the overall noise reduction values of the test specimens was small away from the resonance frequency. In the mass-law region, a slight and proportional improvement in noise reduction was observed by adding damping material. Adding sound absorbtion material to a panel with damping material beneficially increased noise reduction at high frequencies.

The Dilemma of Derelict Gear

NASA Astrophysics Data System (ADS)

Scheld, A. M.; Bilkovic, D. M.; Havens, K. J.

2016-01-01

Every year, millions of pots and traps are lost in crustacean fisheries around the world. Derelict fishing gear has been found to produce several harmful environmental and ecological effects, however socioeconomic consequences have been investigated less frequently. We analyze the economic effects of a substantial derelict pot removal program in the largest estuary of the United States, the Chesapeake Bay. By combining spatially resolved data on derelict pot removals with commercial blue crab (Callinectes sapidus) harvests and effort, we show that removing 34,408 derelict pots led to significant gains in gear efficiency and an additional 13,504 MT in harvest valued at US $21.3 million—a 27% increase above that which would have occurred without removals. Model results are extended to a global analysis where it is seen that US $831 million in landings could be recovered annually by removing less than 10% of the derelict pots and traps from major crustacean fisheries. An unfortunate common pool externality, the degradation of marine environments is detrimental not only to marine organisms and biota, but also to those individuals and communities whose livelihoods and culture depend on profitable and sustainable marine resource use.

Impacts of Changed Extratropical Storm Tracks on Arctic Sea Ice Export through Fram Strait

NASA Astrophysics Data System (ADS)

Wei, J.; Zhang, X.; Wang, Z.

2017-12-01

Studies have indicated a poleward shift of extratropical storm tracks and intensification of Arctic storm activities, in particular on the North Atlantic side of the Arctic Ocean. To improve understanding of dynamic effect on changes in Arctic sea ice mass balance, we examined the impacts of the changed storm tracks and activities on Arctic sea ice export through Fram Strait through ocean-sea ice model simulations. The model employed is the high-resolution Massachusetts Institute of Technology general circulation model (MITgcm), which was forced by the Japanese 25-year Reanalysis (JRA-25) dataset. The results show that storm-induced strong northerly wind stress can cause simultaneous response of daily sea ice export and, in turn, exert cumulative effects on interannual variability and long-term changes of sea ice export. Further analysis indicates that storm impact on sea ice export is spatially dependent. The storms occurring southeast of Fram Strait exhibit the largest impacts. The weakened intensity of winter storms in this region after 1994/95 could be responsible for the decrease of total winter sea ice export during the same time period.

The Dilemma of Derelict Gear.

PubMed

Scheld, A M; Bilkovic, D M; Havens, K J

2016-01-21

Every year, millions of pots and traps are lost in crustacean fisheries around the world. Derelict fishing gear has been found to produce several harmful environmental and ecological effects, however socioeconomic consequences have been investigated less frequently. We analyze the economic effects of a substantial derelict pot removal program in the largest estuary of the United States, the Chesapeake Bay. By combining spatially resolved data on derelict pot removals with commercial blue crab (Callinectes sapidus) harvests and effort, we show that removing 34,408 derelict pots led to significant gains in gear efficiency and an additional 13,504 MT in harvest valued at US $21.3 million--a 27% increase above that which would have occurred without removals. Model results are extended to a global analysis where it is seen that US $831 million in landings could be recovered annually by removing less than 10% of the derelict pots and traps from major crustacean fisheries. An unfortunate common pool externality, the degradation of marine environments is detrimental not only to marine organisms and biota, but also to those individuals and communities whose livelihoods and culture depend on profitable and sustainable marine resource use.

3-D localization of virtual sound sources: effects of visual environment, pointing method, and training.

PubMed

Majdak, Piotr; Goupell, Matthew J; Laback, Bernhard

2010-02-01

The ability to localize sound sources in three-dimensional space was tested in humans. In Experiment 1, naive subjects listened to noises filtered with subject-specific head-related transfer functions. The tested conditions included the pointing method (head or manual pointing) and the visual environment (VE; darkness or virtual VE). The localization performance was not significantly different between the pointing methods. The virtual VE significantly improved the horizontal precision and reduced the number of front-back confusions. These results show the benefit of using a virtual VE in sound localization tasks. In Experiment 2, subjects were provided with sound localization training. Over the course of training, the performance improved for all subjects, with the largest improvements occurring during the first 400 trials. The improvements beyond the first 400 trials were smaller. After the training, there was still no significant effect of pointing method, showing that the choice of either head- or manual-pointing method plays a minor role in sound localization performance. The results of Experiment 2 reinforce the importance of perceptual training for at least 400 trials in sound localization studies.

Effect of the raw materials and mixing ratio of composted wastes on the dynamic of organic matter stabilization and nitrogen availability in composts of Sub-Saharan Africa.

PubMed

Kaboré, Théodore Wind-Tinbnoma; Houot, Sabine; Hien, Edmond; Zombré, Prosper; Hien, Victor; Masse, Dominique

2010-02-01

The effect of raw materials and their proportions in initial mixtures on organic matter (OM) stabilization and nitrogen (N) availability during pit composting in Sub-Saharan Africa was assessed using biochemical fractionation and laboratory incubations to characterize composts sampled throughout the composting process. Stabilization of OM occurred more rapidly in mixtures with slaughter-house wastes, it was progressive in mixture with household refuses while tree leaves compost remained unstable. Carbon mineralization from compost samples was positively correlated to water soluble and hemicellulose-like organic fractions. Mixtures containing large proportions of household refuses reached the highest stability and total N but available N remained weak. Slaughter-house wastes in the initial mixtures made possible to reach good OM stabilization and the largest N availability. The nature of initial mixing influenced composting parameters, OM stabilization and N availability. It is suggested mixing household refuses and slaughter-house wastes with tree leaves to reach better amending and fertilizer qualities of composts.

Interactions between space-based and feature-based attention.

PubMed

Leonard, Carly J; Balestreri, Angela; Luck, Steven J

2015-02-01

Although early research suggested that attention to nonspatial features (i.e., red) was confined to stimuli appearing at an attended spatial location, more recent research has emphasized the global nature of feature-based attention. For example, a distractor sharing a target feature may capture attention even if it occurs at a task-irrelevant location. Such findings have been used to argue that feature-based attention operates independently of spatial attention. However, feature-based attention may nonetheless interact with spatial attention, yielding larger feature-based effects at attended locations than at unattended locations. The present study tested this possibility. In 2 experiments, participants viewed a rapid serial visual presentation (RSVP) stream and identified a target letter defined by its color. Target-colored distractors were presented at various task-irrelevant locations during the RSVP stream. We found that feature-driven attentional capture effects were largest when the target-colored distractor was closer to the attended location. These results demonstrate that spatial attention modulates the strength of feature-based attention capture, calling into question the prior evidence that feature-based attention operates in a global manner that is independent of spatial attention.

Critical evaluation of taeniacidal antibiotic S15-1 (SQ 21, 704) for removal of natural tapeworm infections in dogs and cats.

PubMed

Szanto, J; Lillis, W G; Brown, W E; Sutphin, C F; Maplesden, D C

1979-05-01

The new taeniacidal antibiotic S15-1 (SQ 21,704) was evaluated against naturally occuring infections of Taenia pisiformis in 53 dogs, Dipylidium caninum in 35 dogs, T taeniaformis in 18 cats, and D caninum in 33 cats. It all instances, the compound was administered in gelatine capsules in a single oral dose. The doses tested were between and 200 mg/kg of body weight in dogs and between 15 and 45 mg/kg in cats. In dogs, doses of 25 mg/kg and greater were 100% effective against T pisiformis, whereas a dose of 50 mg/kg was necessary to clear D caninum. In cats, a single oral dose of 22.5 mg/kg was 100% efficacious against T taeniaeformis, and a single dose of 45 mg/kg (the largest dose tested) clearly seven of eight cats of D caninum. The efficacy was limited to tapeworms only; there was no efficacy against nematodes. The antibiotic was well tolerated by both species with no drug-related vomiting or other side-effects observed.

Simulator study of vortex encounters by a twin-engine, commercial, jet transport airplane

NASA Technical Reports Server (NTRS)

Hastings, E. C., Jr.; Keyser, G. L., Jr.

1982-01-01

A simulator study of vortex encounters was conducted for a twin-engine, commercial, jet transport airplane encountering the vortex flow field of a heavy, four-engine, commercial, jet transport airplane in the final-approach configuration. The encounters were conducted with fixed controls and with a pilot using a state-of-the-art, manual-control system. Piloted encounters with the base-line vortex flow field out of ground effect (unattenuated) resulted in initial bank-angle excursions greater than 40 deg, coupled with initial sideslip-angle excursions greater than 10 deg. The severity of these initial upsets was significantly reduced when the vortex center was moved laterally or vertically away from the flight path of the encountering airplane. Smaller reductions occurred when the flow field was attenuated by the flight spoilers on the generating airplane. The largest reduction in the severity of the initial upsets, however, was from aging in ground effect. The severity of the initial upsets of the following airplane was relatively unaffected by the approach speed. Increasing the lift coefficient of the generating airplane resulted in an increase in the severity of the initial upsets.

Assessing whether the 2017 Mw 5.4 Pohang earthquake in South Korea was an induced event

NASA Astrophysics Data System (ADS)

Kim, Kwang-Hee; Ree, Jin-Han; Kim, YoungHee; Kim, Sungshil; Kang, Su Young; Seo, Wooseok

2018-06-01

The moment magnitude (Mw) 5.4 Pohang earthquake, the most damaging event in South Korea since instrumental seismic observation began in 1905, occurred beneath the Pohang geothermal power plant in 2017. Geological and geophysical data suggest that the Pohang earthquake was induced by fluid from an enhanced geothermal system (EGS) site, which was injected directly into a near-critically stressed subsurface fault zone. The magnitude of the mainshock makes it the largest known induced earthquake at an EGS site.

A new species of Lonchophylla Thomas (Chiroptera: Phyllostomidae) from Ecuador

USGS Publications Warehouse

Albuja V., Luis; Gardner, Alfred L.

2005-01-01

We describe Lonchophylla orcesi, sp. nov., from the Choco, a region of high biotic diversity, endemism, and rainfall along the western Andean slopes and Pacific lowlands of Colombia and Ecuador. One of the largest known Lonchophylla, it occurs sympatrically with at least two other species of Lonchophylla including the similar, but somewhat smaller L. robusta. We also recognize L. concava as a Middle American Province species distinct from L. mordax of Brazil and Bolivia on the basis of cranial and dental features.

Solar Flares with some Flair

NASA Image and Video Library

2016-07-23

The Sun produced three M-class (medium-sized) flares in less than 13 hours and the third one had an interesting flourish at the end (July 22-23, 2016). These were the largest flares the Sun had produced this year. The first two flares occurred in quick succession. The third one (see the still taken at 5:38 UT on the 23rd), besides the familiar bright flash of a flare, also spewed out into space a curving string of plasma. http://photojournal.jpl.nasa.gov/catalog/PIA17912

Properties of fiber reinforced plastics about static and dynamic loadings

NASA Astrophysics Data System (ADS)

Kudinov, Vladimir V.; Korneeva, Natalia V.

2016-05-01

A method for investigation of impact toughness of anisotropic polymer composite materials (reinforced plastics) with the help of CM model sample in the configuration of microplastic (micro plastic) and impact pendulum-type testing machine under static and dynamic loadings has been developed. The method is called "Break by Impact" (Impact Break IB). The estimation of impact resistance CFRP by this method showed that an increase in loading velocity ~104 times the largest changes occurs in impact toughness and deformation ability of a material.

The Pocatello Valley, Idaho, earthquake

USGS Publications Warehouse

Rogers, A. M.; Langer, C.J.; Bucknam, R.C.

1975-01-01

A Richter magnitude 6.3 earthquake occurred at 8:31 p.m mountain daylight time on March 27, 1975, near the Utah-Idaho border in Pocatello Valley. The epicenter of the main shock was located at 42.094° N, 112.478° W, and had a focal depth of 5.5 km. This earthquake was the largest in the continental United States since the destructive San Fernando earthquake of February 1971. The main shock was preceded by a magnitude 4.5 foreshock on March 26. 

Ranavirus outbreaks in amphibian populations of northern Idaho

USGS Publications Warehouse

Russell, Danelle M.; Goldberg, Caren S.; Sprague, Laura; Waits, Lisette P.; Green, D. Earl; Schuler, Krysten L.; Rosenblum, Erica Bree

2011-01-01

Ranavirus outbreaks, caused by pathogens in the genus Ranavirus (Family Iridoviridae), were the largest single cause of reported amphibian mass mortality events in the United States from 1996–2001 (Green et al. 2002). Mortality events associated with ranaviruses have been documented on five continents and throughout the latitudes and elevations where amphibians occur (Gray et al. 2009). However, the threat of ranaviruses to amphibian and reptile populations in specific regions is still largely unknown (Chinchar 2002; Gray et al. 2009).

Discovery of the Largest Historic Silicic Submarine Eruption

NASA Astrophysics Data System (ADS)

Carey, Rebecca J.; Wysoczanski, Richard; Wunderman, Richard; Jutzeler, Martin

2014-05-01

It was likely twice the size of the renowned Mount St. Helens eruption of 1980 and perhaps more than 10 times bigger than the more recent 2010 Eyjafjallajökull eruption in Iceland. However, unlike those two events, which dominated world news headlines, in 2012 the daylong submarine silicic eruption at Havre volcano in the Kermadec Arc, New Zealand (Figure 1a; ~800 kilometers north of Auckland, New Zealand), passed without fanfare. In fact, for a while no one even knew it had occurred.

Metapopulation Dynamics of the Mistletoe and Its Host in Savanna Areas with Different Fire Occurrence

PubMed Central

Teodoro, Grazielle Sales; van den Berg, Eduardo; Arruda, Rafael

2013-01-01

Mistletoes are aerial hemiparasitic plants which occupy patches of favorable habitat (host trees) surrounded by unfavorable habitat and may be possibly modeled as a metapopulation. A metapopulation is defined as a subdivided population that persists due to the balance between colonization and extinction in discrete habitat patches. Our aim was to evaluate the dynamics of the mistletoe Psittacanthus robustus and its host Vochysia thyrsoidea in three Brazilian savanna areas using a metapopulation approach. We also evaluated how the differences in terms of fire occurrence affected the dynamic of those populations (two areas burned during the study and one was fire protected). We monitored the populations at six-month intervals. P. robustus population structure and dynamics met the expected criteria for a metapopulation: i) the suitable habitats for the mistletoe occur in discrete patches; (ii) local populations went extinct during the study and (iii) colonization of previously non-occupied patches occurred. The ratio of occupied patches decreased in all areas with time. Local mistletoe populations went extinct due to two different causes: patch extinction in area with no fire and fire killing in the burned areas. In a burned area, the largest decrease of occupied patch ratios occurred due to a fire event that killed the parasites without, however, killing the host trees. The greatest mortality of V. thyrsoidea occurred in the area without fire. In this area, all the dead trees supported mistletoe individuals and no mortality was observed for parasite-free trees. Because P. robustus is a fire sensitive species and V. thyrsoidea is fire tolerant, P. robustus seems to increase host mortality, but its effect is lessened by periodic burning that reduces the parasite loads. PMID:23776554

Assessment of earthquake-induced landslides hazard in El Salvador after the 2001 earthquakes using macroseismic analysis

NASA Astrophysics Data System (ADS)

Esposito, Eliana; Violante, Crescenzo; Giunta, Giuseppe; Ángel Hernández, Miguel

2016-04-01

Two strong earthquakes and a number of smaller aftershocks struck El Salvador in the year 2001. The January 13 2001 earthquake, Mw 7.7, occurred along the Cocos plate, 40 km off El Salvador southern coast. It resulted in about 1300 deaths and widespread damage, mainly due to massive landsliding. Two of the largest earthquake-induced landslides, Las Barioleras and Las Colinas (about 2x105 m3) produced major damage to buildings and infrastructures and 500 fatalities. A neighborhood in Santa Tecla, west of San Salvador, was destroyed. The February 13 2001 earthquake, Mw 6.5, occurred 40 km east-southeast of San Salvador. This earthquake caused over 300 fatalities and triggered several landslides over an area of 2,500 km2 mostly in poorly consolidated volcaniclastic deposits. The La Leona landslide (5-7x105 m3) caused 12 fatalities and extensive damage to the Panamerican Highway. Two very large landslides of 1.5 km3 and 12 km3 produced hazardous barrier lakes at Rio El Desague and Rio Jiboa, respectively. More than 16.000 landslides occurred throughout the country after both quakes; most of them occurred in pyroclastic deposits, with a volume less than 1x103m3. The present work aims to define the relationship between the above described earthquake intensity, size and areal distribution of induced landslides, as well as to refine the earthquake intensity in sparsely populated zones by using landslide effects. Landslides triggered by the 2001 seismic sequences provided useful indication for a realistic seismic hazard assessment, providing a basis for understanding, evaluating, and mapping the hazard and risk associated with earthquake-induced landslides.

The effect of chronic low back pain on tactile suppression during back movements.

PubMed

Van Damme, Stefaan; Van Hulle, Lore; Danneels, Lieven; Spence, Charles; Crombez, Geert

2014-10-01

The aim of the present study was to examine whether tactile suppression, the phenomenon whereby tactile perception is suppressed during movement, would occur in the context of back movements. Of particular interest, it was investigated if tactile suppression in the back would be attenuated in those suffering from chronic low back pain. Individuals with chronic low back pain (N = 30) and a matched control group (N = 24) detected tactile stimuli on three possible locations (back, arm, chest) while performing a back or arm movement, or no movement. We hypothesized that the movements would induce tactile suppression, and that this effect would be largest for low-intense stimuli on the moving body part. We further hypothesized that, during back movements, tactile suppression on the back would be less pronounced in the chronic low back pain group than in the control group. The results showed the expected general tactile suppression effects. The hypothesis of back-specific attenuation of tactile suppression in the chronic low back pain group was not supported. However, back-specific tactile suppression in the chronic low back pain group was less pronounced in those who performed the back movements more slowly. Copyright © 2014 Elsevier B.V. All rights reserved.

Expansion of agricultural oasis in the Heihe River Basin of China: Patterns, reasons and policy implications

NASA Astrophysics Data System (ADS)

Song, Wei; Zhang, Ying

The Heihe River Basin (HRB) is the second largest inland river basin in the arid region of northwestern China. An agricultural oasis is a typical landscape in arid regions providing precious fertile soil, living space and ecological services. The agricultural oasis change has been one of the key issues in sustainable development in recent decades. In this paper, we examined the changes in the agricultural oasis in HRB and analyzed the socio-economic and climatic driving forces behind them. It was found that the agricultural oasis in HRB expanded by 25.11% and 14.82% during the periods of 1986-2000 and 2000-2011, respectively. Most of the newly added agricultural oases in HRB were converted from grassland (40.94%) and unused land (40.22%). The expansion in the agricultural oasis mainly occurred in the middle reaches of HRB, particularly in the counties of Shandan, Minle, Jinta and Jiuquan city. Changes in the rural labor force, annual temperature and precipitation have significant positive effects on agricultural oasis changes, while the ratio of irrigated agricultural oases has significant negative effects on agricultural oasis changes. The agricultural oasis expansion in HRB is the combined effect of human activity and climate change.

Did Irving Langmuir Observe Langmuir Circulations?

NASA Astrophysics Data System (ADS)

D'Asaro, E. A.; Harcourt, R. R.; Shcherbina, A.; Thomson, J. M.; Fox-Kemper, B.

2012-12-01

Although surface waves are known to play an important role in mixing the upper ocean, the current generation of upper ocean boundary layer parameterizations does not include the explicit effects of surface waves. Detailed simulations using LES models which include the Craik-Leibovich wave-current interactions, now provide quantitative predictions of the enhancement of boundary layer mixing by waves. Here, using parallel experiments in Lake Washington and at Ocean Station Papa, we show a clear enhancement of vertical kinetic energy across the entire upper ocean boundary layer which can be attributed to surface wave effects. The magnitude of this effect is close to that predicted by LES models, but is not large, less than a factor of 2 on average, and increased by large Stokes drift and shallow mixed layers. Global estimates show the largest wave enhancements occur on the equatorial side of the westerlies in late Spring, due to the combination of large waves, shallow mixed layers and weak winds. In Lakes, however, the waves and the Craik-Leibovich interactions are weak, making it likely that the counter-rotating vortices famously observed by Irving Langmuir in Lake George were not driven by wave-current interactions.

Thermoase-Derived Flaxseed Protein Hydrolysates and Membrane Ultrafiltration Peptide Fractions Have Systolic Blood Pressure-Lowering Effects in Spontaneously Hypertensive Rats

PubMed Central

Nwachukwu, Ifeanyi D.; Girgih, Abraham T.; Malomo, Sunday A.; Onuh, John O.; Aluko, Rotimi E.

2014-01-01

Thermoase-digested flaxseed protein hydrolysate (FPH) samples and ultrafiltration membrane-separated peptide fractions were initially evaluated for in vitro inhibition of angiotensin I-converting enzyme (ACE) and renin activities. The two most active FPH samples and their corresponding peptide fractions were subsequently tested for in vivo antihypertensive activity in spontaneously hypertensive rats (SHR). The FPH produced with 3% thermoase digestion showed the highest ACE- and renin-inhibitory activities. Whereas membrane ultrafiltration resulted in significant (p < 0.05) increases in ACE inhibition by the <1 and 1–3 kDa peptides, only a marginal improvement in renin-inhibitory activity was observed for virtually all the samples after membrane ultrafiltration. The FPH samples and membrane fractions were also effective in lowering systolic blood pressure (SBP) in SHR with the largest effect occurring after oral administration (200 mg/kg body weight) of the 1–3 kDa peptide fraction of the 2.5% FPH and the 3–5 kDa fraction of the 3% FPH. Such potent SBP-lowering capacity indicates the potential of flaxseed protein-derived bioactive peptides as ingredients for the formulation of antihypertensive functional foods and nutraceuticals. PMID:25302619

Effects of polar solvents on the mechanical behavior of fish scales.

PubMed

Murcia, Sandra; Li, Guihua; Yahyazadehfar, Mobin; Sasser, Mikaela; Ossa, Alex; Arola, D

2016-04-01

Fish scales are unique structural materials that serve as a form of natural armor. In this investigation the mechanical behavior of scales from the Cyprinus carpio was evaluated after exposure to a polar solvent. Uniaxial tensile and tear tests were conducted on specimens prepared from the scales of multiple fish extracted from near the head, middle and tail regions, and after exposure to ethanol for periods from 0 to 24h. Submersion in ethanol caused instantaneous changes in the tensile properties regardless of anatomical site, with increases in the elastic modulus, strength and modulus of toughness exceeding 100%. The largest increase in properties overall occurred in the elastic modulus of scales from the tail region and exceeded 200%. Although ethanol treatment had significant effect on the tensile properties, it had limited influence on the tear resistance. The contribution of ethanol to the mechanical behavior appears to be derived from an increase in the degree of interpeptide hydrogen-bonding of the collagen molecules. Spatial variations in the effects of ethanol exposure on the mechanical behavior arise from the differences in degree of mineralization and lower mineral content in scales of the tail region. Copyright © 2015 Elsevier B.V. All rights reserved.

Anastomotic stenoses occurring after circular stapling in esophageal cancer surgery.

PubMed

Petrin, G; Ruol, A; Battaglia, G; Buin, F; Merigliano, S; Constantini, M; Pavei, P; Cagol, M; Scappin, S; Ancona, E

2000-07-01

Circular staplers have reduced the incidence of anastomotic leaks in esophagovisceral anastomosis. However, the prevalence of stenosis is greater with staplers than with manual suturing. The aim of this study was to analyze potential risk factors for the onset of anastomotic stenoses and to evaluate their treatment and final outcome. Between 1990 and 1995, 187 patients underwent esophagectomy and esophagogastrostomy with anastomosis performed inside the chest using a circular stapler. Twenty-three patients (12.3%) developed an anastomotic stenosis. The incidence of strictures was inversely related to the diameter of the stapler. Concomitant cardiovascular diseases; morphofunctional disorders of the tubulized stomach, such as those related to duodenogastric reflux; and neoadjuvant chemotherapy were also recognized as significant risk factors. Endoscopic dilatations proved safe and were effective in the treatment of most anastomotic stenoses. To reduce the risk of anastomotic stenosis after stapled intrathoracic esophagogastrostomy, adequate vascularization of the viscera being anastomized should be maintained, and it is mandatory to use the largest circular stapler suitable. Furthermore, it is essential to reduce the negative inflammation-inducing effects of duodenogastroesophageal reflux to a minimum. Endoscopic dilatations are safe and effective in curing the great majority of anastomotic stenoses.

The Great Recession, unemployment and suicide

PubMed Central

Norström, Thor; Grönqvist, Hans

2015-01-01

Background How have suicide rates responded to the marked increase in unemployment spurred by the Great Recession? Our paper puts this issue into a wider perspective by assessing (1) whether the unemployment-suicide link is modified by the degree of unemployment protection, and (2) whether the effect on suicide of the present crisis differs from the effects of previous economic downturns. Methods We analysed the unemployment-suicide link using time-series data for 30 countries spanning the period 1960–2012. Separate fixed-effects models were estimated for each of five welfare state regimes with different levels of unemployment protection (Eastern, Southern, Anglo-Saxon, Bismarckian and Scandinavian). We included an interaction term to capture the possible excess effect of unemployment during the Great Recession. Results The largest unemployment increases occurred in the welfare state regimes with the least generous unemployment protection. The unemployment effect on male suicides was statistically significant in all welfare regimes, except the Scandinavian one. The effect on female suicides was significant only in the eastern European country group. There was a significant gradient in the effects, being stronger the less generous the unemployment protection. The interaction term capturing the possible excess effect of unemployment during the financial crisis was not significant. Conclusions Our findings suggest that the more generous the unemployment protection the weaker the detrimental impact on suicide of the increasing unemployment during the Great Recession. PMID:25339416

Water-level decline in the Apalachicola River, Florida, from 1954 to 2004, and effects on floodplain habitats

USGS Publications Warehouse

Light, Helen M.; Vincent, Kirk R.; Darst, Melanie R.; Price, Franklin D.

2006-01-01

From 1954 to 2004, water levels declined in the nontidal reach of the Apalachicola River, Florida, as a result of long-term changes in stage-discharge relations. Channel widening and deepening, which occurred throughout much of the river, apparently caused the declines. The period of most rapid channel enlargement began in 1954 and occurred primarily as a gradual erosional process over two to three decades, probably in response to the combined effect of a dam located at the head of the study reach (106 miles upstream from the mouth of the river), river straightening, dredging, and other activities along the river. Widespread recovery has not occurred, but channel conditions in the last decade (1995-2004) have been relatively stable. Future channel changes, if they occur, are expected to be minor. The magnitude and extent of water-level decline attributable to channel changes was determined by comparing pre-dam stage (prior to 1954) and recent stage (1995-2004) in relation to discharge. Long-term stage data for the pre-dam period and recent period from five streamflow gaging stations were related to discharge data from a single gage just downstream from the dam, by using a procedure involving streamflow lag times. The resulting pre-dam and recent stage-discharge relations at the gaging stations were used in combination with low-flow water-surface profile data from the U.S. Army Corps of Engineers to estimate magnitude of water-level decline at closely spaced locations (every 0.1 mile) along the river. The largest water-level declines occurred at the lowest discharges and varied with location along the river. The largest water-level decline, 4.8 feet, which occurred when sediments were scoured from the streambed just downstream from the dam, has been generally known and described previously. This large decline progressively decreased downstream to a magnitude of 1 foot about 40 river miles downstream from the dam, which is the location that probably marks the downstream limit of the influence of the dam on bed scour. Downstream from that location, previously unreported water-level declines progressively increased to 3 feet at a location 68 miles downstream from the dam, probably as a result of various channel modifications conducted in that part of the river. Water-level declines in the river have substantially changed long-term hydrologic conditions in more than 200 miles of off-channel floodplain sloughs, streams, and lakes and in most of the 82,200 acres of floodplain forests in the nontidal reach of the Apalachicola River. Decreases in duration of floodplain inundation at low discharges were large in the upstream-most 10 miles of the river (20-45 percent) and throughout most of the remaining 75 miles of the nontidal reach (10-25 percent). As a consequence of this decreased inundation, the quantity and quality of floodplain habitats for fish, mussels, and other aquatic organisms have declined, and wetland forests of the floodplain are changing in response to drier conditions. Water-level decline caused by channel change is probably the most serious anthropogenic impact that has occurred so far in the Apalachicola River and floodplain. This decline has been exacerbated by long-term reductions in spring and summer flow, especially during drought periods. Although no trends in total annual flow volumes were detected, long-term decreases in discharge for April, May, July, and August were apparent, and water-level declines during drought conditions resulting from decreased discharge in those 4 months were similar in magnitude to the water-level declines caused by channel changes. The observed changes in seasonal discharge are probably caused by a combination of natural climatic changes and anthropogenic activities in the Apalachicola-Chattahoochee-Flint River Basin. Continued research is needed for geomorphic studies to assist in the design of future floodplain restoration efforts and for hydrologic studies to monitor change

Anatomy of biologically mediated opal speleothems in the World's largest sandstone cave: Cueva Charles Brewer, Chimantá Plateau, Venezuela

NASA Astrophysics Data System (ADS)

Aubrecht, R.; Brewer-Carías, Ch.; Šmída, B.; Audy, M.; Kováčik, Ľ.

2008-01-01

Siliceous speleothems can be formed in sandstone caves. Recently, opal "biospeleothems" have been found in the World's largest cave in Precambrian sandstones on the Chimantá Tepui in Venezuela. The speleothems, although reminiscent of normal stalactites and stalagmites from limestone caves, are in fact large microbialites. More than a dozen forms were distinguished, but they share a common structure and origin. They consist of two main types: 1. fine-laminated columnar stromatolite formed by silicified filamentous microbes (either heterotrophic filamentous bacteria or cyanobacteria) and 2. a porous peloidal stromatolite formed by Nostoc-type cyanobacteria. The first type usually forms the central part and the second type, the outer part, of speleothems. Fungal hyphae, metazoan and plant remains also subordinately contribute to speleothem construction. The speleothems occur out of the reach of flowing water; the main source of silica is the condensed cave moisture which is the main dissolution-reprecipitation agent. Speleothems which originated by encrustation of spider threads are unique.

Evolution of king crabs from hermit crab ancestors

NASA Astrophysics Data System (ADS)

Cunningham, C. W.; Blackstone, N. W.; Buss, L. W.

1992-02-01

KING crabs (Family Lithodidae) are among the world's largest arthropods, having a crab-like morphology and a strongly calcified exoskeleton1-6. The hermit crabs, by contrast, have depended on gastropod shells for protection for over 150 million years5,7. Shell-living has constrained the morphological evolution of hermit crabs by requiring a decalcified asymmetrical abdomen capable of coiling into gastropod shells and by preventing crabs from growing past the size of the largest available shells1-6. Whereas reduction in shell-living and acquisition of a crab-like morphology (carcinization) has taken place independently in several hermit crab lineages, and most dramatically in king crabs1-6, the rate at which this process has occurred was entirely unknown2,7. We present molecular evidence that king crabs are not only descended from hermit crabs, but are nested within the hermit crab genus Pagurus. We estimate that loss of the shell-living habit and the complete carcinization of king crabs has taken between 13 and 25 million years.

Eruptive Trio Seen by STEREO

NASA Image and Video Library

2017-12-08

NASA image acquired May 1, 2010. As an active region rotated into view, it blew out three relatively small eruptions over about two days (Apr. 30 - May 2) as STEREO (Ahead) observed in extreme UV light. The first one was the largest and exhibited a pronounced twisting motion (shown in the still from May 1, 2010). The plasma, not far above the Sun's surface in these images, is ionized Helium heated to about 60,000 degrees. Note, too, the movement of plasma flowing along magnetic field lines that extend out beyond and loop back into the Sun's surface. Such activity occurs every day and is part of the dynamism of the changing Sun. Credit: NASA/GSFC/STEREO To learn more about STEREO go to: soho.nascom.nasa.gov/home.html NASA Goddard Space Flight Center is home to the nation's largest organization of combined scientists, engineers and technologists that build spacecraft, instruments and new technology to study the Earth, the sun, our solar system, and the universe.

Fifteen Years of Operation at NASA's National Transonic Facility with the World's Largest Adjustable Speed Drive

NASA Technical Reports Server (NTRS)

Sydnor, George H.; Bhatia, Ram; Krattiger, Hansueli; Mylius, Justus; Schafer, D.

2012-01-01

In September 1995, a project was initiated to replace the existing drive line at NASA's most unique transonic wind tunnel, the National Transonic Facility (NTF), with a single 101 MW synchronous motor driven by a Load Commutated Inverter (LCI). This Adjustable Speed Drive (ASD) system also included a custom four-winding transformer, harmonic filter, exciter, switch gear, control system, and feeder cable. The complete system requirements and design details have previously been presented and published [1], as well as the commissioning and acceptance test results [2]. The NTF was returned to service in December 1997 with the new drive system powering the fan. Today, this installation still represents the world s largest horizontal single motor/drive combination. This paper describes some significant events that occurred with the drive system during the first 15 years of service. These noteworthy issues are analyzed and root causes presented. Improvements that have substantially increased the long term viability of the system are given.

A Wavelet Based Suboptimal Kalman Filter for Assimilation of Stratospheric Chemical Tracer Observations

NASA Technical Reports Server (NTRS)

Auger, Ludovic; Tangborn, Andrew; Atlas, Robert (Technical Monitor)

2002-01-01

A suboptimal Kalman filter system which evolves error covariances in terms of a truncated set of wavelet coefficients has been developed for the assimilation of chemical tracer observations of CH4. The truncation is carried out in such a way that the resolution of the error covariance, is reduced only in the zonal direction, where gradients are smaller. Assimilation experiments which last 24 days, and used different degrees of truncation were carried out. These reduced the covariance, by 90, 97 and 99 % and the computational cost of covariance propagation by 80, 93 and 96 % respectively. The difference in both error covariance and the tracer field between the truncated and full systems over this period were found to be not growing in the first case, and a growing relatively slowly in the later two cases. The largest errors in the tracer fields were found to occur in regions of largest zonal gradients in the tracer field.

Nonlinearity in rock - Evidence from earth tides

NASA Technical Reports Server (NTRS)

Agnew, D. C.

1981-01-01

The earth is sinusoidally stressed by tidal forces; if the stress-strain relation for rock is nonlinear, energy should appear in an earth tide record at frequencies which are multiples of those of the larger tidal lines. An examination of the signals to be expected for different nonlinear deformation laws shows that for a nonlinear response without dissipation, the largest anomalous signal should occur at twice the forcing frequency, whereas for nonlinear laws involving dissipation (cusped hysteresis loops) the anomalous signal will be greatest at three times this frequency. The size of the signal in the dissipative case depends on the amount by which dissipation affects the particular response being measured. For measurements of strain tides this depends on whether dissipation is assumed to be present throughout the earth or localized around the point of measurement. An analysis of 5.7 years of strain tide records from Pinon Flat, California, shows a small signal at twice the frequency of the largest (M2) tide.

Optimization Strategies for Single-Stage, Multi-Stage and Continuous ADRs

NASA Technical Reports Server (NTRS)

Shirron, Peter J.

2014-01-01

Adiabatic Demagnetization Refrigerators (ADR) have many advantages that are prompting a resurgence in their use in spaceflight and laboratory applications. They are solid-state coolers capable of very high efficiency and very wide operating range. However, their low energy storage density translates to larger mass for a given cooling capacity than is possible with other refrigeration techniques. The interplay between refrigerant mass and other parameters such as magnetic field and heat transfer points in multi-stage ADRs gives rise to a wide parameter space for optimization. This paper first presents optimization strategies for single ADR stages, focusing primarily on obtaining the largest cooling capacity per stage mass, then discusses the optimization of multi-stage and continuous ADRs in the context of the coordinated heat transfer that must occur between stages. The goal for the latter is usually to obtain the largest cooling power per mass or volume, but there can also be many secondary objectives, such as limiting instantaneous heat rejection rates and producing intermediate temperatures for cooling of other instrument components.

Remembering the best and worst of times: memories for extreme outcomes bias risky decisions.

PubMed

Madan, Christopher R; Ludvig, Elliot A; Spetch, Marcia L

2014-06-01

When making decisions on the basis of past experiences, people must rely on their memories. Human memory has many well-known biases, including the tendency to better remember highly salient events. We propose an extreme-outcome rule, whereby this memory bias leads people to overweight the largest gains and largest losses, leading to more risk seeking for relative gains than for relative losses. To test this rule, in two experiments, people repeatedly chose between fixed and risky options, where the risky option led equiprobably to more or less than did the fixed option. As was predicted, people were more risk seeking for relative gains than for relative losses. In subsequent memory tests, people tended to recall the extreme outcome first and also judged the extreme outcome as having occurred more frequently. Across individuals, risk preferences in the risky-choice task correlated with these memory biases. This extreme-outcome rule presents a novel mechanism through which memory influences decision making.

Flood of May 19, 1990, along Perry Creek in Plymouth and Woodbury counties, Iowa

USGS Publications Warehouse

Eash, D.A.

1996-01-01

A water-surface-elevation profile and peak discharges for the flood of May 19, 1990, along Perry Creek in Plymouth and Woodbury Counties, Iowa, are presented in this report. The peak discharge for the May 19,1990, flood on Perry Creek at 38th Street, Sioux City (06600000) is the second largest flood-peak discharge recorded at the streamflow-gaging station for the period 1939-95. The peak discharge for May 19, 1990, of 8,670 cubic feet per second, is approximately equal to the 35-year recurrence-interval discharge. The report provides information on flood stages and discharges and floodflow frequencies for streamflow-gaging stations in the Perry Creek Basin using flood information collected during 1939-95. Information on temporary bench marks and reference points established in the Perry Creek Basin during 1990-93 is also included in the report. A flood history describes rainfall conditions for the three largest floods that occurred during 1939-95 (July 1944, September 1949, and May 1990).

Organic matter losses in German Alps forest soils since the 1970s most likely caused by warming

NASA Astrophysics Data System (ADS)

Prietzel, Jörg; Zimmermann, Lothar; Schubert, Alfred; Christophel, Dominik

2016-07-01

Climate warming is expected to induce soil organic carbon losses in mountain soils that result, in turn, in reduced soil fertility, reduced water storage capacity and positive feedback on climate change. Here we combine two independent sets of measurements of soil organic carbon from forest soils in the German Alps--repeated measurements from 1976 to 2010 and from 1987 to 2011--to show that warming has caused a 14% decline in topsoil organic carbon stocks. The decreases in soil carbon occurred over a period of significant increases in six-month summer temperatures, with the most substantial decreases occurring at sites with large changes in mean annual temperature. Organic carbon stock decreases were largest--on average 32%--in forest soils with initial topsoil organic carbon stocks greater than 8 kg C m-2, which can be found predominantly on calcareous bedrock. However, organic carbon stocks of forest soils with lower initial carbon stocks, as well as soils under pasture or at elevations above 1,150 m, have not changed significantly. We conclude that warming is the most likely reason for the observed losses of soil organic carbon, but that site, land use and elevation may ameliorate the effects of climate change.

The Effect of Aerosols and Clouds on the Retrieval of Infrared Sea Surface Temperatures

NASA Technical Reports Server (NTRS)

Vazquez-Cuervo, Jorge; Armstrong, Edward M.; Harris, Andy

2004-01-01

Comparisons are performed between spatially averaged sea surface temperatures (ASST2) as derived from the second Along-Track Scanning Radiometer (ATSR-2) on board the second European Remote Sensing Satellite (ERS-2) and the NOAA-NASA Advanced Very High Resolution Radiometer (AVHRR) Oceans Pathfinder dataset (MPFSST). Difference maps, MPFSST 2 ASST2, along with the application of a simple statistical regression model to aerosol and cloud data from the Total Ozone Mapping Spectrometer ( TOMS), are used to examine the impact of possible aerosol and cloud contamination. Differences varied regionally, but the largest biases were seen off western Africa. Nighttime and daytime differences off western Africa were reduced from -0.5degrees to -0.2degreesC and from -0.1degrees to 0degreesC, respectively. Significant cloud flagging, based on the model, occurred in the Indian Ocean, the equatorial Pacific, and in the vicinity of the Gulf Stream. Comparisons of the MPFSST and the ASST2 with in situ data from the 2002 version of the World Oceanic Database (WOD02) off western Africa show larger mean differences for the MPFSST. The smallest mean differences occurred for nighttime ASST2 - WOD02 with a value of 0.0degrees +/- 0.4degreesC.

The Possible Potential Therapeutic Targets for Drug Induced Gingival Overgrowth

PubMed Central

Alitheen, Noorjahan Banu

2013-01-01

Gingival overgrowth is a side effect of certain medications. The most fibrotic drug-induced lesions develop in response to therapy with phenytoin, the least fibrotic lesions are caused by cyclosporin A, and the intermediate fibrosis occurs in nifedipine-induced gingival overgrowth. Fibrosis is one of the largest groups of diseases for which there is no therapy but is believed to occur because of a persistent tissue repair program. During connective tissue repair, activated gingival fibroblasts synthesize and remodel newly created extracellular matrix. Proteins such as transforming growth factor (TGF), endothelin-1 (ET-1), angiotensin II (Ang II), connective tissue growth factor (CCN2/CTGF), insulin-like growth factor (IGF), and platelet-derived growth factor (PDGF) appear to act in a network that contributes to the development of gingival fibrosis. Since inflammation is the prerequisite for gingival overgrowth, mast cells and its protease enzymes also play a vital role in the pathogenesis of gingival fibrosis. Drugs targeting these proteins are currently under consideration as antifibrotic treatments. This review summarizes recent observations concerning the contribution of TGF-β, CTGF, IGF, PDGF, ET-1, Ang II, and mast cell chymase and tryptase enzymes to fibroblast activation in gingival fibrosis and the potential utility of agents blocking these proteins in affecting the outcome of drug-induced gingival overgrowth. PMID:23690667

Monitoring reactive microencapsulation dynamics using microfluidics

PubMed Central

Brosseau, Quentin; Baret, Jean-Christophe

2015-01-01

We use microfluidic polydimethylsiloxane (PDMS) devices to measure the kinetics of reactive encapsulations occurring at the interface of emulsion droplets. The formation of the polymeric shell is inferred from the droplet deformability measured in a series of expansion–constriction chambers along the microfluidic chip. With this tool we quantify the kinetic processes governing the encapsulation at the very early stage of shell formation with a time resolution of the order of the millisecond for overall reactions occurring in less than 0.5 s. We perform a comparison of monomer reactivities used for the encapsulation. We study the formation of polyurea microcapsules (PUMCs); the shell formation proceeds at the water–oil interface by an immediate reaction of amines dissolved in the aqueous phase and isocyanates dissolved in the oil phase. We observe that both monomers contribute differently to the encapsulation kinetics. The kinetics of the shell formation process at the oil-in-water (O/W) experiments significantly differs from the water-in-oil (W/O) systems; the component dissolved in the continuous phase has the largest impact on the kinetics. In addition, we quantified the retarding effect on the encapsulation kinetics by the interface stabilizing agent (surfactant). Our approach is valuable for quantifying in situ reactive encapsulation processes and provides guidelines to generate microcapsules with soft interfaces of tailored and controllable interfacial properties. PMID:25705975

OI 630.0 nm Night Airglow Observations during the Geomagnetic Storm on November 20, 2003 at Kolhapur (P43)

NASA Astrophysics Data System (ADS)

Sharma, A. K.; et al.

2006-11-01

sharma_ashokkumar@yahoo.com The ground based photometric observations of OI 630 nm emission line have been carried out from Kolhapur station (Geog. Lat.16.8˚N, Geo. Long 74.2˚E), India during the period of the largest geomagnetic storm of the solar cycle 23 which occurred on 20 November 2003, with minimum Dst index 472 nT occurring around mid-night hours. We observed that on 19 November 2003 which was geomagnetically quiet day, the airglow activity of OI 630 nm emission was subdued and it was decreasing monotonically. However, on the night of November 20, 2003 the enhancement is observed during geomagnetic storm due to the increased electron density at the altitude of the F region which is related to the downward transport of electron from the plasmasphere to the F-region. Airglow intensity at OI 630.0 nm showed increase around midnight on November 21, 2003 but comparatively on a smaller scale. On this night the DST index was about 100 nT. This implies that the effect of the geomagnetic storm persisted on that night also. These observations have been explained by the penetration magnetospheric electric field to the low latitude region and the subsequent modulation of meridional wind during the magnetic disturbance at night.

The influenza epidemic of 1889–90 in selected European cities – a picture based on the reports of two Poznań daily newspapers from the second half of the nineteenth century

PubMed Central

Kempińska-Mirosławska, Bogumiła; WoŸniak-Kosek, Agnieszka

2013-01-01

The largest nineteenth-century epidemic of influenza, called ‘the Russian epidemic,’ arrived in Europe from the east in November and December of 1889. It was one of the first epidemics of influenza that occurred during the period of the rapid development of bacteriology. It was the first epidemic to be so widely commented on in the intensively developing daily press. Daily Polish newspapers published in Poznań, a Polish city that was then under Prussian rule, also had a share in providing information on the epidemic. Press reports not only referred to the local spread of the disease, but also discussed the situation in numerous, often distant, European cities, such as Paris, London, Vienna, and Berlin. Apart from data about where and when the illness occurred, the reports provided: descriptions of symptoms, treatment methods, data on morbidity and mortality, effect on individual people of high rank in the country, information on the activities of public authorities, and impact of the epidemic on daily life. The 1889–1890 influenza epidemic had 2 faces: the real one, discovered while being afflicted with the disease, and the media one, discovered through the information available in the press. PMID:24322721

DOE Office of Scientific and Technical Information (OSTI.GOV)

Katsumori, Tetsuya, E-mail: katsumo@eurus.dti.ne.jp; Kasahara, Toshiyuki; Kin, Yoko

Purpose. To assess uterine artery recanalization, together with tumor devascularization, after embolization using gelatin sponge particles alone for fibroids. Methods. Twenty-seven patients underwent uterine artery embolization (UAE) for fibroids using only gelatin sponge particles. The angiographic endpoint of embolization was defined as near stasis of contrast medium in the ascending segment of the uterine artery. All patients underwent contrast-enhanced magnetic resonance angiography (MRA) before and 4 months after UAE, and contrast-enhanced magnetic resonance imaging (CE-MRI) before, 1 week after, and 4 months after UAE. The visualization of the uterine arteries before and 4 months after UAE was assessed using MRA.more » The infarction rates of the largest tumor were assessed using CE-MRI 1 week after UAE. Results. MRA 4 months after UAE showed 100% (53/53) of the descending and transverse segments, and 88% (43/49) of the ascending segments that had been noted on baseline MRA. The visualization of the ascending segments on MRA 4 months after UAE was identical to that on baseline MRA in 20 of 27 patients (74%). CE-MRI showed complete infarction of the largest tumor in 22 of 27 patients (81%), and 90-99% infarction of the largest tumor in the remaining 5 of 27 patients (19%). Conclusion. Based on the MR study, in most cases uterine artery recanalization occurred, together with sufficient devascularization of fibroids, after UAE using gelatin sponge particles alone.« less

Social impacts of the work loss in cancer survivors.

PubMed

Yamauchi, Hideko; Nakagawa, Chizuko; Fukuda, Takashi

2017-09-01

As cancer frequently occurs during the most productive years of life, our purpose was to estimate the cost of work loss of cancer survivors and develop interventions to minimize the loss. We estimated the cost of the work loss from all cancers resulting from patients' inpatient, outpatient, and non-treatment days. This was calculated with a new method, the product of the "employment rate coefficient × productivity coefficient," making use of data published by the Japanese Ministries. The estimate of work loss on treatment days for all cancers was $1820.21 million in men and $939.38 million in women. In terms of disease classification, lung cancer was the largest cause in men, whereas breast cancer was the largest in women. On non-treatment days, the work losses because of gastric, colon, and lung cancers were large in men, while breast cancer was the largest in women and in total. The estimated loss for all cancers was $3685.506 million in men and $2502.565 million in women, when the product was assumed 0.5. In Japan, breast cancer was considered the leading cause for cost of work loss, and the most influential cause when the product of the "employment rate coefficient × productivity coefficient" for breast cancer was assumed the same as the product for all other types of cancers. It is necessary to establish support systems for working cancer survivors.

Discovering Tau and Muon Solar Neutrino Flares above Backgrounds

NASA Astrophysics Data System (ADS)

Fargion, D.; Moscato, F.

2005-01-01

Solar neutrino flares astronomy is at the edge of its discover. High energy flare particles (protons, alpha) whose self scattering within the solar corona is source of a rich prompt charged pions are also source of sharp solar neutrino "burst" (at tens-hundred MeV) produced by their pion-muon primary decay in flight. This brief (minute) solar neutrino "burst" at largest peak overcome by four-five order of magnitude the steady atmospheric neutrino noise at the Earth. Later on, solar flare particles hitting the terrestrial atmosphere may marginally increase the atmospheric neutrino flux without relevant consequences. Largest prompt "burst" solar neutrino flare may be detected in present or better in future largest neutrino underground neutrino detectors. Our estimate for the recent and exceptional October - November 2003 solar flares gives a number of events above or just near unity for Super-Kamiokande. The neutrino spectra may reflect in a subtle way the neutrino flavour mixing in flight. A surprising tau appearance may even occur for a hard ({E}_{nu}_{mu}--> {E}_{nu}_{tau} > 4 GeV) flare spectra. A comparison of the solar neutrino flare (at their birth place on Sun and after oscillation on the arrival on the Earth) with other neutrino foreground is here described and it offer an independent road map to disentangle the neutrino flavour puzzles and its secret flavour mixing angles .

Background Characterization and Discrimination in the Final Analysis of the CDMS II Phase of the Cryogenic Dark Matter Search

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fritts, Matthew C.

The Cryogenic Dark Matter Search (CDMS) is designed to detectWeakly-Interacting Massive Particles (WIMPs) in the Milky Way halo. The phase known as CDMS II was performed in the Soudan Underground Laboratory. The final set of CDMS II data, collected in 2007-8 and referred to as Runs 125-8, represents the largest exposure to date for the experiment. We seek collisions between WIMPs and atomic nuclei in disk-shaped germanium and silicon detectors. A key design feature is to keep the rate of collisions from known particles producing WIMP-like signals very small. The largest category of such background is interactions with electrons inmore » the detectors that occur very close to one of the faces of the detector. The next largest category is collisions between energetic neutrons that bypass the experimental shielding and nuclei in the detectors. Analytical efforts to discriminate these backgrounds and to estimate the rate at which such discrimination fails have been refined and improved throughout each phase of CDMS. Next-generation detectors for future phases of CDMS require testing at cryogenic test facilities. One such facility was developed at the University of Minnesota in 2007 and has been used continuously since then to test detectors for the next phase of the experiment, known as SuperCDMS.« less

Hydrogeology, water quality, water budgets, and simulated responses to hydrologic changes in Santa Rosa and San Simeon Creek ground-water basins, San Luis Obispo County, California

USGS Publications Warehouse

Yates, Eugene B.; Van Konyenburg, Kathryn M.

1998-01-01

Santa Rosa and San Simeon Creeks are underlain by thin, narrow ground-water basins that supply nearly all water used for local agricultural and municipal purposes. The creeks discharge to the Pacific Ocean near the northwestern corner of San Luis Obispo County, California. The basins contain heterogeneous, unconsolidated alluvial deposits and are underlain by relatively impermeable bedrock. Both creeks usually stop flowing during the summer dry season, and most of the pumpage during that time is derived from ground-water storage. Annual pumpage increased substantially during 1956?88 and is now a large fraction of basin storage capacity. Consequently, dry-season water levels are lower and the water supply is more vulnerable to drought. The creeks are the largest source of ground-water recharge, and complete basin recharge can occur within the first few weeks of winter streamflow. Agricultural and municipal pumpages are the largest outflows and cause dry-season water-level declines throughout the San Simeon Basin. Pumping effects are more localized in the Santa Rosa Basin because of subsurface flow obstructions. Even without pumpage, a large quantity of water naturally drains out of storage at the upper ends of the basins during the dry season. Ground water is more saline in areas close to the coast than in inland areas. Although seawater intrusion has occurred in the past, it probably was not the cause of high salinity in 1988?89. Ground water is very hard, and concentrations of dissolved solids, chloride, iron, and manganese exceed drinking-water standards in some locations. Probability distributions of streamflow were estimated indirectly from a 120-year rainfall record because the periods of record for local stream-gaging stations were wetter than average. Dry-season durations with recurrence intervals between 5 and 43 years are likely to dry up some wells but not cause seawater intrusion. A winter with no streamflow is likely to occur about every 32 years and to result in numerous dry wells, seawater intrusion, and subsidence. Digital ground-water-flow models were used to estimate several items in the ground-water budgets and to investigate the effects of pumpage and drought. The models also were used to investigate the hydrologic effects of selected water-resources management alternatives. Selection of alternatives was not constrained by issues related to water rights, which were under dispute during the study. Increases in the area and intensity of irrigation could increase agricultural water demand by 26 to 35 percent, an increase that would lower water levels by as much as 10 feet and possibly cause subsidence in the lower Santa Rosa Basin. An additional municipal well in the lower Santa Rosa Basin could withdraw 100 acre-feet per year without causing seawater intrusion, but subsidence might occur. Transferring 270 acre-feet per year of treated wastewater from a percolation area near the coast to an area about 0.5 mile upstream of the municipal well field in the San Simeon Basin could raise upstream water levels by as much as 12 feet without causing significant water-table mounding or seawater intrusion. Decreases in agricultural pumping after a winter without streamflow could prevent seawater intrusion while allowing municipal pumping to continue at normal rates.

Waterborne disease in Norway: emphasizing outbreaks in groundwater systems.

PubMed

Kvitsand, Hanne M L; Fiksdal, Liv

2010-01-01

In this study, we compiled and examined available data on waterborne disease outbreaks (1984-2007) in Norway, with emphasis on groundwater systems. A total of 102 waterborne outbreaks and 17,243 disease cases were reported during the period 1984-2007. The proportion of outbreaks related to groundwater reflected the proportion of groundwater works in Norway (40%). The proportion of disease cases corresponded to the proportion of persons supplied by groundwater (15%). Norovirus was identified as the most important disease causing agent in groundwater systems. No clear seasonal correlation was observed for Norovirus outbreaks in groundwater, but the largest outbreaks occurred during winter season. All outbreaks of campylobacteriosis occurred during March to November, with a peak in July-September, which correlates with the occurrence of coliforms in Norwegian groundwater in bedrock wells.

Spatial patterns in electoral wards with high lymphoma incidence in Yorkshire health region.

PubMed Central

Barnes, N.; Cartwright, R. A.; O'Brien, C.; Roberts, B.; Richards, I. D.; Bird, C. C.

1987-01-01

The possibilities of clustering between those electoral wards which display higher than expected incidences of cases of the lymphomas occurring between 1978 and 1982 are examined. Clusters are defined as being those wards with cases in excess (at a probability of less than 10%) which are geographically adjacent to each other. A separate analysis extends the definition of cluster to include high incidence wards that are adjacent or separated by one other ward. The results indicate that many high incidence lymphoma wards do occur close together and when computer simulations are used to compute expected results, many of the observed results are shown to be highly improbable both in the overall number of clustering wards and in the largest number of wards comprising a 'cluster'. PMID:3663469

Conflict and Compromise: Catholic and Public Hospital Partnerships

PubMed Central

Wall, Barbra Mann

2010-01-01

This article analyzes the tensions and uneasy negotiations, based on a case study, that occurred among Catholic sisters, administrators, bishops, physicians, and the Vatican for more than seven years at a hospital in Austin, Texas. Here, the largest health care system in the city, which was Catholic, joined with the local public, tax-supported hospital that provided the majority of reproductive health care services in the region. A clash resulted over whether the hospital could continue providing sterilization and contraceptive services to its primarily poor patients. This article examines the fierce debates that occurred, especially over emergency contraception and attempts to develop creative solutions after a hierarchical crackdown from the Vatican. The end result was a compromise that included the creation of a “hospital within a hospital.” PMID:20067093

Effects of nuclear cross sections at different energies on the radiation hazard from galactic cosmic rays.

PubMed

Lin, Z W; Adams, J H

2007-03-01

The radiation hazard for astronauts from galactic cosmic rays (GCR) is a major obstacle to long-duration human space exploration. Space radiation transport codes have been developed to calculate the radiation environment on missions to the Moon, Mars, and beyond. We have studied how uncertainties in fragmentation cross sections at different energies affect the accuracy of predictions from such radiation transport calculations. We find that, in deep space, cross sections at energies between 0.3 and 0.85 GeV/nucleon have the largest effect in solar maximum GCR environments. At the International Space Station, cross sections at higher energies have the largest effect due to the geomagnetic cutoff.

Use of the new Nitrogen Index tier zero to assess the effects of nitrogen fertilizer on N2O emissions from cropping systems in Mexico

USDA-ARS?s Scientific Manuscript database

Mexico is one of the largest users of N fertilizer in the world, and the 2nd largest user in Latin America after Brazil. Across large areas of Mexico, N fertilizers are being over-applied, resulting in lower N use efficiencies. Mexico’s trace gas inventory (in CO2 equivalents) reports that agricultu...