NASA Astrophysics Data System (ADS)
Delsman, J. R.; Hu-a-ng, K. R. M.; Vos, P. C.; de Louw, P. G. B.; Oude Essink, G. H. P.; Stuyfzand, P. J.; Bierkens, M. F. P.
2013-11-01
Management of coastal fresh groundwater reserves requires a thorough understanding of the present-day groundwater salinity distribution and its possible future development. However, coastal groundwater often still reflects a complex history of marine transgressions and regressions, and is only rarely in equilibrium with current boundary conditions. In addition, the distribution of groundwater salinity is virtually impossible to characterize satisfactorily, complicating efforts to model and predict coastal groundwater flow. A way forward may be to account for the historical development of groundwater salinity when modeling present-day coastal groundwater flow. In this paper, we construct a palaeo-hydrogeological model to simulate the evolution of groundwater salinity in the coastal area of the Netherlands throughout the Holocene. While intended as a perceptual tool, confidence in our model results is warranted by a good correspondence with a hydrochemical characterization of groundwater origin. Model results attest to the impact of groundwater density differences on coastal groundwater flow on millennial timescales and highlight their importance in shaping today's groundwater salinity distribution. Not once reaching steady-state throughout the Holocene, our results demonstrate the long-term dynamics of salinity in coastal aquifers. This stresses the importance of accounting for the historical evolution of coastal groundwater salinity when modeling present-day coastal groundwater flow, or when predicting impacts of e.g. sea level rise on coastal aquifers. Of more local importance, our findings suggest a more significant role of pre-Holocene groundwater in the present-day groundwater salinity distribution in the Netherlands than previously recognized. The implications of our results extend beyond understanding the present-day distribution of salinity, as the proven complex history of coastal groundwater also holds important clues for understanding and predicting the distribution of other societally relevant groundwater constituents.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ann V. Rowan; Simon H. Brocklehurst; David M. Schultz
2014-05-01
Glaciers respond to climate variations and leave geomorphic evidence that represents an important terrestrial paleoclimate record. However, the accuracy of paleoclimate reconstructions from glacial geology is limited by the challenge of representing mountain meteorology in numerical models. Precipitation is usually treated in a simple manner and yet represents difficult-to-characterize variables such as amount, distribution, and phase. Furthermore, precipitation distributions during a glacial probably differed from present-day interglacial patterns. We applied two models to investigate glacier sensitivity to temperature and precipitation in the eastern Southern Alps of New Zealand. A 2-D model was used to quantify variations in the length ofmore » the reconstructed glaciers resulting from plausible precipitation distributions compared to variations in length resulting from change in mean annual air temperature and precipitation amount. A 1-D model was used to quantify variations in length resulting from interannual climate variability. Assuming that present-day interglacial values represent precipitation distributions during the last glacial, a range of plausible present-day precipitation distributions resulted in uncertainty in the Last Glacial Maximum length of the Pukaki Glacier of 17.1?km (24%) and the Rakaia Glacier of 9.3?km (25%), corresponding to a 0.5°C difference in temperature. Smaller changes in glacier length resulted from a 50% decrease in precipitation amount from present-day values (-14% and -18%) and from a 50% increase in precipitation amount (5% and 9%). Our results demonstrate that precipitation distribution can produce considerable variation in simulated glacier extents and that reconstructions of paleoglaciers should include this uncertainty.« less
Characterising the three-dimensional ozone distribution of a tidally locked Earth-like planet
NASA Astrophysics Data System (ADS)
Proedrou, Elisavet; Hocke, Klemens
2016-06-01
We simulate the 3D ozone distribution of a tidally locked Earth-like exoplanet using the high-resolution, 3D chemistry-climate model CESM1(WACCM) and study how the ozone layer of a tidally locked Earth (TLE) (Ω _{TLE}= 1/365 days) differs from that of our present-day Earth (PDE) (Ω _{PDE}= 1/1 day). The middle atmosphere reaches a steady state asymptotically within the first 80 days of the simulation. An upwelling, centred on the subsolar point, is present on the day side while a downwelling, centred on the antisolar point, is present on the night side. In the mesosphere, we find similar global ozone distributions for the TLE and the PDE, with decreased ozone on the day side and enhanced ozone on the night side. In the lower mesosphere, a jet stream transitions into a large-scale vortex around a low-pressure system, located at low latitudes of the TLE night side. In the middle stratosphere, the concentration of odd oxygen is approximately equal to that of the ozone [({O}x) ≈ ({O}3)]. At these altitudes, the lifetime of odd oxygen is ˜16 h and the transport processes significantly contribute to the global distribution of stratospheric ozone. Compared to the PDE, where the strong Coriolis force acts as a mixing barrier between low and high latitudes, the transport processes of the TLE are governed by jet streams variable in the zonal and meridional directions. In the middle stratosphere of the TLE, we find high ozone values on the day side, due to the increased production of atomic oxygen on the day side, where it immediately recombines with molecular oxygen to form ozone. In contrast, the ozone is depleted on the night side, due to changes in the solar radiation distribution and the presence of a downwelling. As a result of the reduced Coriolis force, the tropical and extratropical air masses are well mixed and the global temperature distribution of the TLE stratosphere has smaller horizontal gradients than the PDE. Compared to the PDE, the total ozone column global mean is reduced by ˜19.3 %. The day side and the night side total ozone column means are reduced by 23.21 and 15.52 %, respectively. Finally, we present the total ozone column (TOC) maps as viewed by a remote observer for four phases of the TLE during its revolution around the star. The mean TOC values of the four phases of the TLE vary by up to 23 %.
Minimal effects of latitude on present-day speciation rates in New World birds
Rabosky, Daniel L.; Title, Pascal O.; Huang, Huateng
2015-01-01
The tropics contain far greater numbers of species than temperate regions, suggesting that rates of species formation might differ systematically between tropical and non-tropical areas. We tested this hypothesis by reconstructing the history of speciation in New World (NW) land birds using BAMM, a Bayesian framework for modelling complex evolutionary dynamics on phylogenetic trees. We estimated marginal distributions of present-day speciation rates for each of 2571 species of birds. The present-day rate of speciation varies approximately 30-fold across NW birds, but there is no difference in the rate distributions for tropical and temperate taxa. Using macroevolutionary cohort analysis, we demonstrate that clades with high tropical membership do not produce species more rapidly than temperate clades. For nearly any value of present-day speciation rate, there are far more species in the tropics than the temperate zone. Any effects of latitude on speciation rate are marginal in comparison to the dramatic variation in rates among clades. PMID:26019156
Parallel Harmony Search Based Distributed Energy Resource Optimization
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ceylan, Oguzhan; Liu, Guodong; Tomsovic, Kevin
2015-01-01
This paper presents a harmony search based parallel optimization algorithm to minimize voltage deviations in three phase unbalanced electrical distribution systems and to maximize active power outputs of distributed energy resources (DR). The main contribution is to reduce the adverse impacts on voltage profile during a day as photovoltaics (PVs) output or electrical vehicles (EVs) charging changes throughout a day. The IEEE 123- bus distribution test system is modified by adding DRs and EVs under different load profiles. The simulation results show that by using parallel computing techniques, heuristic methods may be used as an alternative optimization tool in electricalmore » power distribution systems operation.« less
SiC Design Guide: Manufacture of Silicon Carbide Products (Briefing charts)
2010-06-08
DISTRIBUTION STATEMENT A: Approved for public release; distribution is unlimited. 13. SUPPLEMENTARY NOTES Presented at Mirror Technology Days, Boulder...coatings. 15. SUBJECT TERMS Mirrors , structures, silicon carbide, design, inserts, coatings, pockets, ribs, bonding, threads 16. SECURITY...Prescribed by ANSI Std. 239.18 purify protect transport SiC Design Guide Manufacture of Silicon Carbide Products Mirror Technology Days June 7 to 9, 2010
NASA Astrophysics Data System (ADS)
Kobulnicky, Henry A.; Kiminki, Daniel C.; Lundquist, Michael J.; Burke, Jamison; Chapman, James; Keller, Erica; Lester, Kathryn; Rolen, Emily K.; Topel, Eric; Bhattacharjee, Anirban; Smullen, Rachel A.; Vargas Álvarez, Carlos A.; Runnoe, Jessie C.; Dale, Daniel A.; Brotherton, Michael M.
2014-08-01
We analyze orbital solutions for 48 massive multiple-star systems in the Cygnus OB2 association, 23 of which are newly presented here, to find that the observed distribution of orbital periods is approximately uniform in log P for P < 45 days, but it is not scale-free. Inflections in the cumulative distribution near 6 days, 14 days, and 45 days suggest key physical scales of sime0.2, sime0.4, and sime1 A.U. where yet-to-be-identified phenomena create distinct features. No single power law provides a statistically compelling prescription, but if features are ignored, a power law with exponent β ~= -0.22 provides a crude approximation over P = 1.4-2000 days, as does a piece-wise linear function with a break near 45 days. The cumulative period distribution flattens at P > 45 days, even after correction for completeness, indicating either a lower binary fraction or a shift toward low-mass companions. A high degree of similarity (91% likelihood) between the Cyg OB2 period distribution and that of other surveys suggests that the binary properties at P <~ 25 days are determined by local physics of disk/clump fragmentation and are relatively insensitive to environmental and evolutionary factors. Fully 30% of the unbiased parent sample is a binary with period P < 45 days. Completeness corrections imply a binary fraction near 55% for P < 5000 days. The observed distribution of mass ratios 0.2 < q < 1 is consistent with uniform, while the observed distribution of eccentricities 0.1 < e < 0.6 is consistent with uniform plus an excess of e ~= 0 systems. We identify six stars, all supergiants, that exhibit aperiodic velocity variations of ~30 km s-1 attributed to atmospheric fluctuations.
Security of Distributed-Phase-Reference Quantum Key Distribution
NASA Astrophysics Data System (ADS)
Moroder, Tobias; Curty, Marcos; Lim, Charles Ci Wen; Thinh, Le Phuc; Zbinden, Hugo; Gisin, Nicolas
2012-12-01
Distributed-phase-reference quantum key distribution stands out for its easy implementation with present day technology. For many years, a full security proof of these schemes in a realistic setting has been elusive. We solve this long-standing problem and present a generic method to prove the security of such protocols against general attacks. To illustrate our result, we provide lower bounds on the key generation rate of a variant of the coherent-one-way quantum key distribution protocol. In contrast to standard predictions, it appears to scale quadratically with the system transmittance.
Springer, Yuri P.; Jarnevich, Catherine S.; Barnett, David T.; Monaghan, Andrew J.; Eisen, Rebecca J.
2015-01-01
The Lone star tick (Amblyomma americanum L.) is the primary vector for pathogens of significant public health importance in North America, yet relatively little is known about its current and potential future distribution. Building on a published summary of tick collection records, we used an ensemble modeling approach to predict the present-day and future distribution of climatically suitable habitat for establishment of the Lone star tick within the continental United States. Of the nine climatic predictor variables included in our five present-day models, average vapor pressure in July was by far the most important determinant of suitable habitat. The present-day ensemble model predicted an essentially contiguous distribution of suitable habitat extending to the Atlantic coast east of the 100th western meridian and south of the 40th northern parallel, but excluding a high elevation region associated with the Appalachian Mountains. Future ensemble predictions for 2061–2080 forecasted a stable western range limit, northward expansion of suitable habitat into the Upper Midwest and western Pennsylvania, and range contraction along portions of the Gulf coast and the lower Mississippi river valley. These findings are informative for raising awareness of A. americanum-transmitted pathogens in areas where the Lone Star tick has recently or may become established.
Assessment of sodium conductor distribution cable
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
1979-06-01
The study assesses the barriers and incentives for using sodium conductor distribution cable. The assessment considers environmental, safety, energy conservation, electrical performance and economic factors. Along with all of these factors considered in the assessment, the sodium distribution cable system is compared to the present day alternative - an aluminum conductor system. (TFD)
Chance-Constrained Day-Ahead Hourly Scheduling in Distribution System Operation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jiang, Huaiguang; Zhang, Yingchen; Muljadi, Eduard
This paper aims to propose a two-step approach for day-ahead hourly scheduling in a distribution system operation, which contains two operation costs, the operation cost at substation level and feeder level. In the first step, the objective is to minimize the electric power purchase from the day-ahead market with the stochastic optimization. The historical data of day-ahead hourly electric power consumption is used to provide the forecast results with the forecasting error, which is presented by a chance constraint and formulated into a deterministic form by Gaussian mixture model (GMM). In the second step, the objective is to minimize themore » system loss. Considering the nonconvexity of the three-phase balanced AC optimal power flow problem in distribution systems, the second-order cone program (SOCP) is used to relax the problem. Then, a distributed optimization approach is built based on the alternating direction method of multiplier (ADMM). The results shows that the validity and effectiveness method.« less
NASA Technical Reports Server (NTRS)
Geller, Margaret J.; Huchra, J. P.
1991-01-01
Present-day understanding of the large-scale galaxy distribution is reviewed. The statistics of the CfA redshift survey are briefly discussed. The need for deeper surveys to clarify the issues raised by recent studies of large-scale galactic distribution is addressed.
Patricia A. Flebbe
1997-01-01
Current distributions of native brook trout (Salvelinus fontinalis) in the Southern Appalachians are restricted to upper elevations by multiple factors, including habitat requirements, introduced rainbow (Oncorhynchus mykiss) and brown (Salmo trutta) trout, and other human activities. Present-day distribution of brook trout habitat is already fragmented. Increased...
Land processes lead to surprising patterns in atmospheric residence time
NASA Astrophysics Data System (ADS)
van der Ent, R.; Tuinenburg, O.
2017-12-01
Our research using atmospheric moisture tracking methods shows that the global average atmospheric residence time of evaporation is 8-10 days. This residence time appears to be Gamma distributed with a higher probability of shorter than average residence times and a long tail. As a consequence the median of this residence time is around 5 days. In some places in the world the first few hours/days after evaporation there seems to be a little chance for a moisture particle to precipitate again, which is reflected by a Gamma distribution having a shape parameter below 1. In this study we present global maps of this parameter using different datasets (GLDAS and ERA-Interim). The shape parameter is as such also a measure for the land-atmospheric coupling strength along the path of the atmospheric water particle. We also find that different evaporation components: canopy interception, soil evaporation and transpiration appear to have different residence time distributions. We find a daily cycle in the residence time distribution over land, which is not present over the oceans. In this paper we will show which of the evaporation components is mainly responsible for this daily pattern and thus exhibits the largest daily cycle of land-atmosphere coupling strength.
Isotopic constraints on crustal growth and recycling
NASA Technical Reports Server (NTRS)
Jacobsen, Stein B.
1988-01-01
The Sm-Nd isotopic data on clastic and chemical sediments are used with the present-day age distribution of continental crustal rocks to estimate the rates of crustal accretion, growth and recycling throughout earth's history. A new method for interpreting Nd model ages on both chemical and clastic sediments is proposed. A general relationship is derived between the mean crustal residence time of material recycled from the crust to the mantle (i.e., sediments), the mean age of the crust, and the crustal growth and recycling rates. This relationship takes into account the fact that the age distribution of material in the continental crust is generally different from the age distribution of material recycled into the mantle. The episodic nature of the present-day age distribution in crustal rocks results in similar episodicity in the accretion and recycling rates. The results suggest that by about 3.8 Ga ago, about 40 percent of the present continental volume was present. Recycling rates were extremely high 3-4 Ga ago and declined rapidly to an insignificant value of about 0.1 cu km/a during most of the Phanerozoic. The Nd model age pattern on sediments suggests a fairly high rate of growth during the Phanerozoic.
Evidence of Periodicity in Ancient Egyptian Calendars of Lucky and Unlucky Days
NASA Astrophysics Data System (ADS)
Porceddu, P.; Jetsu, L.; Markkanen, T.; Toivari-Viitala, J.
2008-10-01
This article presents an experiment in time series analysis, specifically the Rayleigh Test, applied to the ancient Egyptian calendars of lucky and unlucky days recorded in papyri P. Cairo 86637, P. BM 10474 and P. Sallier IV. The Rayleigh Test is used to determine whether the lucky and unlucky days are distributed randomly within the year, or whether they exhibit periodicity. The results of the analysis show beyond doubt that some of the lucky days were distributed according to a lunar calendar. The cycles of the moon thus played an important role in the religious thinking of the Egyptians. Other periods found using the Rayleigh Test are connected to the civil calendar, the mythological symbolism of the twelfth hour of the day and possibly the period of variation of the star Algol.
Towards an initial mass function for giant planets
NASA Astrophysics Data System (ADS)
Carrera, Daniel; Davies, Melvyn B.; Johansen, Anders
2018-07-01
The distribution of exoplanet masses is not primordial. After the initial stage of planet formation, gravitational interactions between planets can lead to the physical collision of two planets, or the ejection of one or more planets from the system. When this occurs, the remaining planets are typically left in more eccentric orbits. In this report we demonstrate how the present-day eccentricities of the observed exoplanet population can be used to reconstruct the initial mass function of exoplanets before the onset of dynamical instability. We developed a Bayesian framework that combines data from N-body simulations with present-day observations to compute a probability distribution for the mass of the planets that were ejected or collided in the past. Integrating across the exoplanet population, one can estimate the initial mass function of exoplanets. We find that the ejected planets are primarily sub-Saturn-type planets. While the present-day distribution appears to be bimodal, with peaks around ˜1MJ and ˜20M⊕, this bimodality does not seem to be primordial. Instead, planets around ˜60M⊕ appear to be preferentially removed by dynamical instabilities. Attempts to reproduce exoplanet populations using population synthesis codes should be mindful of the fact that the present population may have been depleted of sub-Saturn-mass planets. Future observations may reveal that young giant planets have a more continuous size distribution with lower eccentricities and more sub-Saturn-type planets. Lastly, there is a need for additional data and for more research on how the system architecture and multiplicity might alter our results.
Toward an initial mass function for giant planets
NASA Astrophysics Data System (ADS)
Carrera, Daniel; Davies, Melvyn B.; Johansen, Anders
2018-05-01
The distribution of exoplanet masses is not primordial. After the initial stage of planet formation, gravitational interactions between planets can lead to the physical collision of two planets, or the ejection of one or more planets from the system. When this occurs, the remaining planets are typically left in more eccentric orbits. In this report we demonstrate how the present-day eccentricities of the observed exoplanet population can be used to reconstruct the initial mass function of exoplanets before the onset of dynamical instability. We developed a Bayesian framework that combines data from N-body simulations with present-day observations to compute a probability distribution for the mass of the planets that were ejected or collided in the past. Integrating across the exoplanet population, one can estimate the initial mass function of exoplanets. We find that the ejected planets are primarily sub-Saturn type planets. While the present-day distribution appears to be bimodal, with peaks around ˜1MJ and ˜20M⊕, this bimodality does not seem to be primordial. Instead, planets around ˜60M⊕ appear to be preferentially removed by dynamical instabilities. Attempts to reproduce exoplanet populations using population synthesis codes should be mindful of the fact that the present population may have been been depleted of sub-Saturn-mass planets. Future observations may reveal that young giant planets have a more continuous size distribution with lower eccentricities and more sub-Saturn type planets. Lastly, there is a need for additional data and for more research on how the system architecture and multiplicity might alter our results.
First-Passage-Time Distribution for Variable-Diffusion Processes
NASA Astrophysics Data System (ADS)
Barney, Liberty; Gunaratne, Gemunu H.
2017-05-01
First-passage-time distribution, which presents the likelihood of a stock reaching a pre-specified price at a given time, is useful in establishing the value of financial instruments and in designing trading strategies. First-passage-time distribution for Wiener processes has a single peak, while that for stocks exhibits a notable second peak within a trading day. This feature has only been discussed sporadically—often dismissed as due to insufficient/incorrect data or circumvented by conversion to tick time—and to the best of our knowledge has not been explained in terms of the underlying stochastic process. It was shown previously that intra-day variations in the market can be modeled by a stochastic process containing two variable-diffusion processes (Hua et al. in, Physica A 419:221-233, 2015). We show here that the first-passage-time distribution of this two-stage variable-diffusion model does exhibit a behavior similar to the empirical observation. In addition, we find that an extended model incorporating overnight price fluctuations exhibits intra- and inter-day behavior similar to those of empirical first-passage-time distributions.
Teaching Wealth Distribution in High School
ERIC Educational Resources Information Center
Neumann, Richard
2015-01-01
This article presents detailed instructional plans for a two-day, high school-level lesson on wealth distribution in society. The terms "income" and "wealth" are defined and compared, and the significance of studying wealth is discussed. Resources for the lesson are identified, and a pedagogical mode is outlined in relation to…
The McDonald Observatory lunar laser ranging project
NASA Technical Reports Server (NTRS)
Silverberg, E. C.
1978-01-01
A summary of the activities of the McDonald lunar laser ranging station at Fort Davis for the FY 77-78 fiscal year is presented. The lunar laser experiment uses the observatory 2.7m reflecting telescope on a thrice-per-day, 21-day-per-lunation schedule. Data are recorded on magnetic tapes and sent to the University of Texas at Austin where the data is processed. After processing, the data is distributed to interested analysis centers and later to the National Space Science Data Center where it is available for routine distribution. Detailed reports are published on the McDonald operations after every fourth lunation or approximately once every 115 days. These reports contain a day-by-day documentation of the ranging activity, detailed discussions of the equipment development efforts, and an abundance of other information as is needed to document and archive this important data type.
NASA Astrophysics Data System (ADS)
Fleming, Z. L.; Doherty, R. M.; von Schneidemesser, E.; Cooper, O. R.; Malley, C.; Colette, A.; Xu, X.; Pinto, J. P.; Simpson, D.; Schultz, M. G.; Hamad, S.; Moola, R.; Solberg, S.; Feng, Z.
2017-12-01
Using stations from the TOAR surface ozone database, this study quantifies present-day global and regional distributions of five ozone metrics relevant for both short-term and long-term human exposure. These metrics were explored at ozone monitoring sites globally, and re-classified for this project as urban or non-urban using population densities and night-time lights. National surface ozone limit values are usually related to an annual number of exceedances of daily maximum 8-hour running mean (MDA8), with many countries not even having any ozone limit values. A discussion and comparison of exceedances in the different ozone metrics, their locations and the seasonality of exceedances provides clues as to the regions that potentially have more serious ozone health implications. Present day ozone levels (2010-2014) have been compared globally and show definite geographical differences (see Figure showing the annual 4th highest MDA8 for present day ozone for all non-urban stations). Higher ozone levels are seen in western compared to eastern US, and between southern and northern Europe, and generally higher levels in east Asia. The metrics reflective of peak concentrations show highest values in western North America, southern Europe and East Asia. A number of the metrics show similar distributions of North-South gradients, most prominent across Europe and Japan. The interquartile range of the regional ozone metrics was largest in East Asia, higher for urban stations in Asia but higher for non-urban stations in Europe and North America. With over 3000 monitoring stations included in this analysis and despite the higher densities of monitoring stations in Europe, north America and East Asia, this study provides the most comprehensive global picture to date of surface ozone levels in terms of health-relevant metrics.
NASA Astrophysics Data System (ADS)
Santos-Alamillos, Francisco J.; Brayshaw, David J.; Methven, John; Thomaidis, Nikolaos S.; Ruiz-Arias, José A.; Pozo-Vázquez, David
2017-11-01
The concept of a European super-grid for electricity presents clear advantages for a reliable and affordable renewable power production (photovoltaics and wind). Based on the mean-variance portfolio optimization analysis, we explore optimal scenarios for the allocation of new renewable capacity at national level in order to provide to energy decision-makers guidance about which regions should be mostly targeted to either maximize total production or reduce its day-to-day variability. The results show that the existing distribution of renewable generation capacity across Europe is far from optimal: i.e. a ‘better’ spatial distribution of resources could have been achieved with either a ~31% increase in mean power supply (for the same level of day-to-day variability) or a ~37.5% reduction in day-to-day variability (for the same level of mean productivity). Careful planning of additional increments in renewable capacity at the European level could, however, act to significantly ameliorate this deficiency. The choice of where to deploy resources depends, however, on the objective being pursued—if the goal is to maximize average output, then new capacity is best allocated in the countries with highest resources, whereas investment in additional capacity in a north/south dipole pattern across Europe would act to most reduce daily variations and thus decrease the day-to-day volatility of renewable power supply.
Abundance profiling of extremely metal-poor stars and supernova properties in the early universe
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tominaga, Nozomu; Iwamoto, Nobuyuki; Nomoto, Ken'ichi, E-mail: tominaga@konan-u.ac.jp, E-mail: iwamoto.nobuyuki@jaea.go.jp, E-mail: nomoto@astron.s.u-tokyo.ac.jp
2014-04-20
After the big bang nucleosynthesis, the first heavy element enrichment in the universe was made by a supernova (SN) explosion of a population (Pop) III star (Pop III SN). The abundance ratios of elements produced from Pop III SNe are recorded in abundance patterns of extremely metal-poor (EMP) stars. The observations of the increasing number of EMP stars have made it possible to statistically constrain the explosion properties of Pop III SNe. We present Pop III SN models whose nucleosynthesis yields well reproduce, individually, the abundance patterns of 48 such metal-poor stars as [Fe/H] ≲ – 3.5. We then derivemore » relations between the abundance ratios of EMP stars and certain explosion properties of Pop III SNe: the higher [(C + N)/Fe] and [(C + N)/Mg] ratios correspond to the smaller ejected Fe mass and the larger compact remnant mass, respectively. Using these relations, the distributions of the abundance ratios of EMP stars are converted to those of the explosion properties of Pop III SNe. Such distributions are compared with those of the explosion properties of present day SNe: the distribution of the ejected Fe mass of Pop III SNe has the same peak as that of the present day SNe but shows an extended tail down to ∼10{sup –2}-10{sup –5} M {sub ☉}, and the distribution of the mass of the compact remnant of Pop III SNe is as wide as that of the present-day, stellar-mass black holes. Our results demonstrate the importance of large samples of EMP stars obtained by ongoing and future EMP star surveys and subsequent high-dispersion spectroscopic observations in clarifying the nature of Pop III SNe in the early universe.« less
NASA Technical Reports Server (NTRS)
Goldhirsh, Julius; Musiani, Bert H.
1989-01-01
During a period spanning more than 5 years, low elevation radar measurements of rain were systematically obtained in the mid-Atlantic coast of the U.S. Drop size distribution measurements with a disdrometer were also acquired on the same rain days. The drop size data were utilized to convert the radar reflectivity factors to estimated rain rates for the respective rain days of operation. Applying high level algorithms to the rain data, core values of rain intensities were identified (peak rain rates), and families of rain rate isopleths analyzed. In particular, equicircle diameters of the family of isopleths enveloping peak rain intensities were statistically characterized. The presented results represents the analysis of two rain days, 12 radar scans, corresponding to 430 culled rain rate isopleths from an available data base of 22,000 contours, approximately 100 scans encompassing 17 rain days. The results presented show trends of the average rain rate vs. contour scale dimensions, and cumulative distributions of rain cell dimensions which belong to core families of precipitation.
Future electro-optical sensors and processing in urban operations
NASA Astrophysics Data System (ADS)
Grönwall, Christina; Schwering, Piet B.; Rantakokko, Jouni; Benoist, Koen W.; Kemp, Rob A. W.; Steinvall, Ove; Letalick, Dietmar; Björkert, Stefan
2013-10-01
In the electro-optical sensors and processing in urban operations (ESUO) study we pave the way for the European Defence Agency (EDA) group of Electro-Optics experts (IAP03) for a common understanding of the optimal distribution of processing functions between the different platforms. Combinations of local, distributed and centralized processing are proposed. In this way one can match processing functionality to the required power, and available communication systems data rates, to obtain the desired reaction times. In the study, three priority scenarios were defined. For these scenarios, present-day and future sensors and signal processing technologies were studied. The priority scenarios were camp protection, patrol and house search. A method for analyzing information quality in single and multi-sensor systems has been applied. A method for estimating reaction times for transmission of data through the chain of command has been proposed and used. These methods are documented and can be used to modify scenarios, or be applied to other scenarios. Present day data processing is organized mainly locally. Very limited exchange of information with other platforms is present; this is performed mainly at a high information level. Main issues that arose from the analysis of present-day systems and methodology are the slow reaction time due to the limited field of view of present-day sensors and the lack of robust automated processing. Efficient handover schemes between wide and narrow field of view sensors may however reduce the delay times. The main effort in the study was in forecasting the signal processing of EO-sensors in the next ten to twenty years. Distributed processing is proposed between hand-held and vehicle based sensors. This can be accompanied by cloud processing on board several vehicles. Additionally, to perform sensor fusion on sensor data originating from different platforms, and making full use of UAV imagery, a combination of distributed and centralized processing is essential. There is a central role for sensor fusion of heterogeneous sensors in future processing. The changes that occur in the urban operations of the future due to the application of these new technologies will be the improved quality of information, with shorter reaction time, and with lower operator load.
Characteristics of bacterial and fungal aerosols during the autumn haze days in Xi'an, China
NASA Astrophysics Data System (ADS)
Li, Yanpeng; Fu, Honglei; Wang, Wei; Liu, Jun; Meng, Qinglong; Wang, Wenke
2015-12-01
In recent years, haze pollution has become one of the most critical environmental issues in Xi'an, China, with particular matter (PM) being one of the top pollutants. As an important fraction of PM, bioaerosols may have adverse effects on air quality and human health. In this study, to better understand the characteristics of such biological aerosols, airborne microbial samples were collected by using an Andersen six-stage sampler in Xi'an from October 8th to 22nd, 2014. The concentration, size distribution and genera of airborne viable bacteria and fungi were comparably investigated during the haze days and non-haze days. Correlations of bioaerosol levels with meteorological parameters and PM concentrations were also examined. The results showed that the daily average concentrations of airborne viable bacteria and fungi during the haze days, 1102.4-1736.5 and 1466.2-1703.9 CFU/m3, respectively, were not only much higher than those during the non-haze days, but also exceeded the recommended permissible limit values. Comparing to size distributions during the non-haze days, slightly different patterns for bacterial aerosols and similar single-peak distribution pattern for fungal aerosols were observed during the haze days. Moreover, more allergic and infectious genera (e.g. Neisseria, Aspergillus, and Paecilomyces) in bioaerosols were identified during the haze days than during non-haze days. The present results reveal that bioaerosols may have more significant effects on public health and urban air quality during the haze days than during non-haze days.
Jacobson, Robert B.; Gran, K.B.
1999-01-01
During the last 160 years, land-use changes in the Ozarks have had the potential to cause widespread, low-intensity delivery of excess amounts of gravel-sized sediment to stream channels. Previous studies have indicated that this excess gravel bedload is moving in wave-like forms through Ozarks drainage basins. The longitudinal, areal distribution of gravel bars along 160 km of the Current River, Missouri, was evaluated to determine the relative effects of valley-scale controls, tributary basin characteristics, and lagged sediment transport in creating areas of gravel accumulations. The longitudinal distribution of gravel-bar area shows a broad scale wave-like form with increases in gravel-bar area weakly associated with tributary junctions. Secondary peaks of gravel area with 1·8–4·1 km spacing (disturbance reaches) are superimposed on the broad form. Variations in valley width explain some, but not all, of the short-spacing variation in gravel-bar area. Among variables describing tributary drainage basin morphometry, present-day land use and geologic characteristics, only drainage area and road density relate even weakly to gravel-bar areal inventories. A simple, channel network-based sediment routing model shows that many of the features of the observed longitudinal gravel distribution can be replicated by uniform transport of sediment from widespread disturbances through a channel network. These results indicate that lagged sediment transport may have a dominant effect on the synoptic spatial distribution of gravel in Ozarks streams; present-day land uses are only weakly associated with present-day gravel inventories; and valley-scale characteristics have secondary controls on gravel accumulations in disturbance reaches.
NASA Astrophysics Data System (ADS)
Jiang, Y.; Wu, X.; van den Broeke, M. R.; Munneke, P. K.; Simonsen, S. B.; van der Wal, W.; Vermeersen, B. L.
2013-12-01
The ice sheet in Polar Regions stores the largest freshwater bodies on Earth, sufficient to elevate global sea level by more than 65 meters if melted. The earth may have entered an intensive ice-melting episode, possibly due to anthropogenic global warming rather than natural orbit variations. Determining present-day ice mass balance, however, is complicated by the fact that most observations contain both present day ice melting signal and residual signals from past glacier melting. Despite decades of progress in geodynamic modeling and new observations, significant uncertainties remain in both. The key to separate present-day ice mass change and signals from past melting is to include data of different physical characteristics. We conducted a new global kinematic inversion scheme to estimate both present-day ice melting and past glacier signatures simultaneously and assess their contribution to current and future global mean sea level change. Our approach is designed to invert and separate present-day melting signal in the spherical harmonic domain using a globally distributed interdisciplinary data with distinct physical information. Interesting results with unprecedented precisions have been achieved so far. We will present our results of the estimated present-day ice mass balance trend in both Greenland and Antarctica ice sheet as well as other regions where significant mass change occurs.
Low-flow frequency analyses for streams in west-central Florida
Hammett, K.M.
1985-01-01
The log-Pearson type III distribution was used for defining low-flow frequency at 116 continuous-record streamflow stations in west-central Florida. Frequency distributions were calculated for 1, 3, 7, 14, 30, 60, 90, 120, and 183 consecutive-day periods for recurrence intervals of 2, 5, 10, and 20 years. Discharge measurements at more than 100 low-flow partial-record stations and miscellaneous discharge-measurement stations were correlated with concurrent daily mean discharge at continuous-record stations. Estimates of the 7-day, 2-year; 7-day, 10-year; 30-day, 2-year; and 30-day, 10-year discharges were made for most of the low-flow partial-record and miscellaneous discharge-measurement stations based on those correlations. Multiple linear-regression analysis was used in an attempt to mathematically relate low-flow frequency data to basin characteristics. The resulting equations showed an apparent bias and were considered unsatisfactory for use in estimating low-flow characteristics. Maps of the 7-day, 10-year and 30-day, 10-year low flows are presented. Techniques that can be used to estimate low-flow characteristics at an ungaged site are also provided. (USGS)
Garriguet, Didier
2016-04-01
Estimates of the prevalence of adherence to physical activity guidelines in the population are generally the result of averaging individual probability of adherence based on the number of days people meet the guidelines and the number of days they are assessed. Given this number of active and inactive days (days assessed minus days active), the conditional probability of meeting the guidelines that has been used in the past is a Beta (1 + active days, 1 + inactive days) distribution assuming the probability p of a day being active is bounded by 0 and 1 and averages 50%. A change in the assumption about the distribution of p is required to better match the discrete nature of the data and to better assess the probability of adherence when the percentage of active days in the population differs from 50%. Using accelerometry data from the Canadian Health Measures Survey, the probability of adherence to physical activity guidelines is estimated using a conditional probability given the number of active and inactive days distributed as a Betabinomial(n, a + active days , β + inactive days) assuming that p is randomly distributed as Beta(a, β) where the parameters a and β are estimated by maximum likelihood. The resulting Betabinomial distribution is discrete. For children aged 6 or older, the probability of meeting physical activity guidelines 7 out of 7 days is similar to published estimates. For pre-schoolers, the Betabinomial distribution yields higher estimates of adherence to the guidelines than the Beta distribution, in line with the probability of being active on any given day. In estimating the probability of adherence to physical activity guidelines, the Betabinomial distribution has several advantages over the previously used Beta distribution. It is a discrete distribution and maximizes the richness of accelerometer data.
NASA Astrophysics Data System (ADS)
Mazzotti, S.; Tarayoun, A.; Marechal, A.; Audet, P.
2017-12-01
The Northern Cordillera of North America is a type example of present-day strain distribution across a wide orogeny. Several geodynamic models are proposed to explain this large-scale tectonic activity, with two main end-members: strain transfer from the Yakutat collision zone (orogenic float) and strain transfer from upper mantle convection (lithosphere basal traction). One of the main differences between these is the lithosphere vertical rheology profile: the former requires significant crust - mantle decoupling to allow far field strain transfer, whereas the latter requires a vertically coupled lithosphere. Here we combine recent data across the eastern region of the Northern Cordillera (eastern Alaska, Yukon, western Northwest Territories) to characterize its states of strain rate, stress, and crustal and lithospheric structure, in order to test the role of the Yakutat collision and upper mantle convection in its present-day tectonics. Recent GPS data confirm the radial, east- to northeastward motion of the central Yukon and foreland belt (Mackenzie and Richardson Mountains), albeit at a much lower velocity than previously proposed. This motion is primarily accommodated by E-W to NE-SW shortening, mainly in the foreland belt, and small to near-zero lateral motion on the major Denali and Tintina strike-slip faults. Seismic anisotropy data further suggest that these two major faults, like most of the Yukon Cordillera, have kept their early Cenozoic crustal and upper mantle structures, as shown by the fault-parallel (NW-SE) fast anisotropy orientation. We use these new data, combined with numerical models of strain distribution under various boundary conditions, to provide constraints on the respective role of the Yakutat collision and upper mantle convection in the present-day tectonics. Preliminary results suggest that, whichever the driving mechanism (or combination thereof), the total strain associated with the present-day tectonics must remain small in order to preserve the inherited crustal and mantle fabrics. Such small cumulative strain appears in contradiction with a thin decoupling layer (such as lower crust decoupling in the orogenic float model) and seems more suggestive of distributed shear across a large part of the lithosphere.
Gibs, J.; Stackelberg, P.E.; Furlong, E.T.; Meyer, M.; Zaugg, S.D.; Lippincott, R.L.
2007-01-01
Ninety eight pharmaceuticals and other organic compounds (POOCs) that were amended to samples of chlorinated drinking-water were extracted and analyzed 1, 3, 6, 8, and 10 days after amendment to determine whether the total chlorine residual reacted with the amended POOCs in drinking water in a time frame similar to the residence time of drinking water in a water distribution system. Results indicated that if all 98 were present in the finished drinking water from a drinking-water treatment plant using free chlorine at 1.2??mg/L as the distribution system disinfectant residual, 52 POOCs would be present in the drinking water after 10??days at approximately the same concentration as in the newly finished drinking water. Concentrations of 16 POOCs would be reduced by 32% to 92%, and 22 POOCs would react completely with residual chlorine within 24??h. Thus, the presence of free chlorine residual is an effective means for transforming some POOCs during distribution. ?? 2006 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Shannon, Andrew Brian; Dawson, Rebekah
2018-04-01
Planet formation remains a poorly understood process, in part because of our limited access to the intermediate phases of planetesimal and protoplanet growth. Today, the vast majority of the accessible remaining planetesimals and protoplanets reside within the Hot Trans-Neptunian Object population. This population has been depleted by 99% - 99.9% over the course of the Solar system's history, and as such the present day size-number distribution may be incomplete at the large size end. We show that such lost protoplanets would have left signatures in the dynamics of the present-day Trans-Neptunian Populations, and their primordial number can thus be statistically limited by considering the survival of ultra-wide binary TNOs, the Cold Classical Kuiper belt, and the resonant populations. We compare those limits to the predicted size-number distribution of various planetesimal and proto-planet growth models.
Keith, S A; Baird, A H; Hughes, T P; Madin, J S; Connolly, S R
2013-07-22
Species richness gradients are ubiquitous in nature, but the mechanisms that generate and maintain these patterns at macroecological scales remain unresolved. We use a new approach that focuses on overlapping geographical ranges of species to reveal that Indo-Pacific corals are assembled within 11 distinct faunal provinces. Province limits are characterized by co-occurrence of multiple species range boundaries. Unexpectedly, these faunal breaks are poorly predicted by contemporary environmental conditions and the present-day distribution of habitat. Instead, faunal breaks show striking concordance with geological features (tectonic plates and mantle plume tracks). The depth range over which a species occurs, its larval development rate and genus age are important determinants of the likelihood that species will straddle faunal breaks. Our findings indicate that historical processes, habitat heterogeneity and species colonization ability account for more of the present-day biogeographical patterns of corals than explanations based on the contemporary distribution of reefs or environmental conditions.
Keith, S. A.; Baird, A. H.; Hughes, T. P.; Madin, J. S.; Connolly, S. R.
2013-01-01
Species richness gradients are ubiquitous in nature, but the mechanisms that generate and maintain these patterns at macroecological scales remain unresolved. We use a new approach that focuses on overlapping geographical ranges of species to reveal that Indo-Pacific corals are assembled within 11 distinct faunal provinces. Province limits are characterized by co-occurrence of multiple species range boundaries. Unexpectedly, these faunal breaks are poorly predicted by contemporary environmental conditions and the present-day distribution of habitat. Instead, faunal breaks show striking concordance with geological features (tectonic plates and mantle plume tracks). The depth range over which a species occurs, its larval development rate and genus age are important determinants of the likelihood that species will straddle faunal breaks. Our findings indicate that historical processes, habitat heterogeneity and species colonization ability account for more of the present-day biogeographical patterns of corals than explanations based on the contemporary distribution of reefs or environmental conditions. PMID:23698011
Gibs, Jacob; Stackelberg, Paul E; Furlong, Edward T; Meyer, Michael; Zaugg, Steven D; Lippincott, Robert Lee
2007-02-01
Ninety eight pharmaceuticals and other organic compounds (POOCs) that were amended to samples of chlorinated drinking-water were extracted and analyzed 1, 3, 6, 8, and 10 days after amendment to determine whether the total chlorine residual reacted with the amended POOCs in drinking water in a time frame similar to the residence time of drinking water in a water distribution system. Results indicated that if all 98 were present in the finished drinking water from a drinking-water treatment plant using free chlorine at 1.2 mg/L as the distribution system disinfectant residual, 52 POOCs would be present in the drinking water after 10 days at approximately the same concentration as in the newly finished drinking water. Concentrations of 16 POOCs would be reduced by 32% to 92%, and 22 POOCs would react completely with residual chlorine within 24 h. Thus, the presence of free chlorine residual is an effective means for transforming some POOCs during distribution.
NASA Astrophysics Data System (ADS)
Alex, Aneesh; Chaney, Eric J.; Criley, Jennifer M.; Spillman, Darold R.; Hutchison, Phaedra B.; Li, Joanne; Marjanovic, Marina; Frey, Steve; Cook, Steven; Boppart, Stephen A.; Arp, Zane A.
2017-02-01
Currently there is a lack of in vivo techniques to evaluate the spatial bio-distribution of dermal drugs over time without the need to take multiple serial biopsies. To address this gap, we investigated the use of multi-photon optical imaging methods to non-invasively track drug distribution on miniature pig (Species: Sus scrofa, Strain: Göttingen) skin in vivo. Minipig skin is the standard comparative research model to human skin, and is anatomically and functionally similar. We employed fluorescence lifetime imaging microscopy (FLIM) to visualize the spatial distribution and residency time of a topically applied experimental dermatological cream. This was made possible by the endogenous fluorescent optical properties of the experimental drug (fluorescence lifetime > 3000 ps). Two different drug formulations were applied on 2 minipigs for 7 consecutive days, with the control creams applied on the contralateral side, followed by 7 days of post-application monitoring using a multi-modal optical imaging system (MPTflex-CARS, JenLab, Germany). FLIM images were obtained from the treated regions 24 hr post-application from day 1 to day 14 that allowed visualization of cellular and sub-cellular features associated with different dermal layers non-invasively to a depth of 200 µm. Five punch biopsies per animal were obtained from the corresponding treated regions between days 8 and 14 for bioanalytical analysis and comparison with results obtained using FLIM. In conclusion, utilization of non-invasive optical biopsy methods for dermal drug evaluation can provide true longitudinal monitoring of drug spatial distribution, remove sampling limitations, and be more time-efficient compared to traditional methods.
NASA Technical Reports Server (NTRS)
Sagan, Carl; Thompson, W. Reid; Chyba, Christopher F.; Khare, B. N.
1991-01-01
A review and partial summary of projects within several areas of research generally involving the origin, distribution, chemistry, and spectral/dielectric properties of volatiles and organic materials in the outer solar system and early terrestrial environments are presented. The major topics covered include: (1) impact delivery of volatiles and organic compounds to the early terrestrial planets; (2) optical constants measurements; (3) spectral classification, chemical processes, and distribution of materials; and (4) radar properties of ice, hydrocarbons, and organic heteropolymers.
The Distribution of Carbon Monoxide in the GOCART Model
NASA Technical Reports Server (NTRS)
Fan, Xiaobiao; Chin, Mian; Einaudi, Franco (Technical Monitor)
2000-01-01
Carbon monoxide (CO) is an important trace gas because it is a significant source of tropospheric Ozone (O3) as well as a major sink for atmospheric hydroxyl radical (OH). The distribution of CO is set by a balance between the emissions, transport, and chemical processes in the atmosphere. The Georgia Tech/Goddard Global Ozone Chemistry Aerosol Radiation and Transport (GOCART) model is used to simulate the atmospheric distribution of CO. The GOCART model is driven by the assimilated meteorological data from the Goddard Earth Observing System Data Assimilation System (GEOS DAS) in an off-line mode. We study the distribution of CO on three time scales: (1) day to day fluctuation produced by the synoptic waves; (2) seasonal changes due to the annual cycle of CO sources and sinks; and (3) interannual variability induced by dynamics. Comparison of model results with ground based and remote sensing measurements will also be presented.
Spatial distributions of heating, cooling, and industrial degree-days in Turkey
NASA Astrophysics Data System (ADS)
Yildiz, I.; Sosaoglu, B.
2007-11-01
The degree-day method is commonly used to estimate energy consumption for heating and cooling in residential, commercial and industrial buildings, as well as in greenhouses, livestock facilities, storage facilities and warehouses. This article presents monthly and yearly averages and spatial distributions of heating, cooling, and industrial degree-days at the base temperatures of 18 °C and 20 °C, 18 °C and 24 °C, and 7 °C and 13 °C, respectively; as well as the corresponding number of days in Turkey. The findings presented here will facilitate the estimation of heating and cooling energy consumption for any residential, commercial and industrial buildings in Turkey, for any period of time (monthly, seasonal, etc.). From this analysis it will also be possible to compare and design alternative building systems in terms of energy efficiencies. If one prefers to use set point temperatures to indicate the resumption of the heating season would also be possible using the provided information in this article. In addition, utility companies and manufacturing/marketing companies of HVAC systems would be able to easily determine the demand, marketing strategies and policies based on the findings in this study.
Trends and Variability of Global Fire Emissions Due To Historical Anthropogenic Activities
NASA Astrophysics Data System (ADS)
Ward, Daniel S.; Shevliakova, Elena; Malyshev, Sergey; Rabin, Sam
2018-01-01
Globally, fires are a major source of carbon from the terrestrial biosphere to the atmosphere, occurring on a seasonal cycle and with substantial interannual variability. To understand past trends and variability in sources and sinks of terrestrial carbon, we need quantitative estimates of global fire distributions. Here we introduce an updated version of the Fire Including Natural and Agricultural Lands model, version 2 (FINAL.2), modified to include multiday burning and enhanced fire spread rate in forest crowns. We demonstrate that the improved model reproduces the interannual variability and spatial distribution of fire emissions reported in present-day remotely sensed inventories. We use FINAL.2 to simulate historical (post-1700) fires and attribute past fire trends and variability to individual drivers: land use and land cover change, population growth, and lightning variability. Global fire emissions of carbon increase by about 10% between 1700 and 1900, reaching a maximum of 3.4 Pg C yr-1 in the 1910s, followed by a decrease to about 5% below year 1700 levels by 2010. The decrease in emissions from the 1910s to the present day is driven mainly by land use change, with a smaller contribution from increased fire suppression due to increased human population and is largest in Sub-Saharan Africa and South Asia. Interannual variability of global fire emissions is similar in the present day as in the early historical period, but present-day wildfires would be more variable in the absence of land use change.
DISTRIBUTION OF 14C-ATRAZINE FOLLOWING AN ACUTE LACTATIONAL EXPOSURE IN THE WISTAR RAT.
The purpose of the present study was to examine the distribution of atrazine in the lactating dam and suckling neonate following an acute exposure to either 2 or 4 mg/kg 14C-atrazine (14C-ATR) by gavage. 14C-ATR was administered to the nursing dam on postnatal day 3 by oral gavag...
Introduction to Deaf-Blindness Workshop.
ERIC Educational Resources Information Center
Rhodes, Larry
This document presents the agenda and materials distributed at a 1-day introductory workshop on deaf-blindness. Introductory material explains the workshop's purpose and rules. A short test contrasts facts and myths about deaf-blindness. A handout presents information on the dynamics of deaf-blindness, etiologies in the adult deaf-blind…
The solar spectrum at typical clear weather days
NASA Technical Reports Server (NTRS)
Boer, K. W.
1976-01-01
The solar spectrum in the range of 300 is less than lambda is less than 1500nm is given for five typical clear weather days. These days are selected to represent typical seasonal conditions in respect to airmass water vapor, ozone, and turbidity. Present data are reviewed, and specific conditions are selected. The spectral distribution of the irradiance is given for the direct component, the scattered skylight, the total flux on a horizontal surface, and the flux on an inclined surface normal to the direct beam.
Bodie, D; Bennett-Clarke, C A; Davis, K; Postelwaite, J P; Chiaia, N L; Rhoades, R W
1997-01-01
Previous experiments from this laboratory have indicated that transection of the infraorbital nerve (ION, the trigeminal [V] branch that supplies the mystacial vibrissae follicles) at birth and in adulthood has markedly different effects on galanin immunoreactivity in the V brainstem complex. Adult nerve transection increases galanin immunoreactivity in the superficial layers of V subnucleus caudalis (SpC) only, while neonatal nerve transection results in increased galanin expression in vibrissae-related primary afferents throughout the V brainstem complex. The present study describes the distribution of binding sites for this peptide in the mature and developing V ganglion and brainstem complex and determines the effects of neonatal and adult ION damage and the associated changes in galanin levels upon their distribution and density. Galanin binding sites are densely distributed in all V brainstem subnuclei and are particularly dense in V subnucleus interpolaris and the superficial layers of SpC. They are present at birth (P-0) and their distribution is similar to that in adult animals. Transection of the ION in adulthood and examination of brainstem 7 days later indicated marked reductions in the density of galanin binding sites in the V brainstem complex. With the exception of the superficial laminae of SpC, the same reduction in density remained apparent in rats that survived > 45 days after nerve cuts. Transection of the ION on P-0 resulted in no change in the density of galanin binding sites in the brainstem after either 7 or > 60 days survival. These results indicate that densely distributed galanin binding sites are present in the V brainstem complex of both neonatal and adult rats, that they are located in regions not innervated by galanin-positive axons, and that their density is not significantly influenced by large lesion-induced changes in the primary afferent content of their natural ligand.
NASA Astrophysics Data System (ADS)
Wu, Po-Feng; van der Wel, Arjen; Gallazzi, Anna; Bezanson, Rachel; Pacifici, Camilla; Straatman, Caroline; Franx, Marijn; Barišić, Ivana; Bell, Eric F.; Brammer, Gabriel B.; Calhau, Joao; Chauke, Priscilla; van Houdt, Josha; Maseda, Michael V.; Muzzin, Adam; Rix, Hans-Walter; Sobral, David; Spilker, Justin; van de Sande, Jesse; van Dokkum, Pieter; Wild, Vivienne
2018-03-01
Drawing from the LEGA-C data set, we present the spectroscopic view of the stellar population across a large volume- and mass-selected sample of galaxies at large look-back time. We measure the 4000 Å break (D n 4000) and Balmer absorption line strengths (probed by Hδ) from 1019 high-quality spectra of z = 0.6–1.0 galaxies with M * = 2 × 1010 M ⊙ to 3 × 1011 M ⊙. Our analysis serves as a first illustration of the power of high-resolution, high signal-to-noise ratio continuum spectroscopy at intermediate redshifts as a qualitatively new tool to constrain galaxy formation models. The observed D n 4000–EW(Hδ) distribution of our sample overlaps with the distribution traced by present-day galaxies, but z ∼ 0.8 galaxies populate that locus in a fundamentally different manner. While old galaxies dominate the present-day population at all stellar masses >2 × 1010 M ⊙, we see a bimodal D n 4000–EW(Hδ) distribution at z ∼ 0.8, implying a bimodal light-weighted age distribution. The light-weighted age depends strongly on stellar mass, with the most massive galaxies >1 × 1011 M ⊙ being almost all older than 2 Gyr. At the same time, we estimate that galaxies in this high-mass range are only ∼3 Gyr younger than their z ∼ 0.1 counterparts, at odds with purely passive evolution given a difference in look-back time of >5 Gyr; younger galaxies must grow to >1011 M ⊙ in the meantime, or small amounts of young stars must keep the light-weighted ages young. Star-forming galaxies at z ∼ 0.8 have stronger Hδ absorption than present-day galaxies with the same D n 4000, implying larger short-term variations in star formation activity.
Present-day Mars' Seismicity Predicted from 3-D Thermal Evolution Models of Interior Dynamics
NASA Astrophysics Data System (ADS)
Knapmeyer, M.; Plesa, A. C.; Golombek, M.
2016-12-01
The InSight (Interior exploration using Seismic Investigations, Geodesy and Heat Transport) mission, to be launched in 2018, will carry the first in-situ seismic and heat flow instruments as well as a precision tracking on Mars. This Discovery-class mission will perform the most comprehensive geophysical investigation of the planet and provide an important baseline to constrain the present-day interior structure and heat budget of the planet, and, in turn, the thermal and chemical evolution of its interior. As the InSight lander will perform the measurements at a single location, numerical simulations of planetary interiors will greatly help to interpret the data in a global context. In this study we have used a series of numerical models of thermal evolution in a 3-D spherical geometry to assess the magnitude of present-day Mars seismicity. Our models assume a fixed crust with a variable thickness as inferred from gravity and topography data, that is enriched in radiogenic heat sources according to the surface abundances inferred from gamma-ray measurements. We test a diversity of parameters by varying the mantle reference viscosity as well as the depth-dependence of the viscosity, considering constant and variable thermal expansivity, varying the crustal thermal conductivity and the size of the core [1]. Our results predict an annual moment release between 1.60 x 1016 Nm and 5.46 x 1018 Nm similar to the values presented previously in [2] and [3]. However, while [2] used a mapping of tectonic surface faults to predict the spatial distribution of epicenters, we derive the distribution from the thermal evolution. Besides the Null-Hypothesis of a uniform distribution and the model of [2], this provides a new, self-consistent, competing hypothesis for both the amount and distribution of seismicity on Mars. [1] Plesa et al., LPSC, 2016 [2] Knapmeyer et al., JGR, 2006 [3] Golombek et al., Science 1992; LPSC 2002
Pedroza-González, Alexander; García-Romo, Gina S; Aguilar-León, Diana; Calderon-Amador, Juana; Hurtado-Ortiz, Raquel; Orozco-Estevez, Hector; Lambrecht, Bart N; Estrada-García, Iris; Hernández-Pando, Rogelio; Flores-Romo, Leopoldo
2004-01-01
Scarce information exists about the role of lung antigen-presenting cells (APCs) in vivo during pulmonary tuberculosis. As APCs activate cellular immunity, following intratracheal inoculation with virulent Mycobacterium tuberculosis, we assessed in situ lung APC recruitment, distribution, granuloma involvement, morphology and mycobacterial burden by using MHC-CII, CD14, scavenger receptor class A (SRA), the murine dendritic cell (DC)-restricted marker CD11c and Ziehl–Neelsen staining. CD11c+ DC and CD14+ cell recruitment into lungs appeared by day 14, continuing until day 60. MHC-CII+ cells increased since day 7, persisting until day 60. Thus, virulent mycobacteria delays (14–21 days) lung APC recruitment compared to model antigens and nonvirulent bacilli (24–48 h). Regarding granuloma constitution, highly bacillary CD14+ and SRA+ cells were centrally located. MHC-CII+ cells were more peripheral, with less mycobacteria. CD11c+ cells were heterogeneously distributed within granulomas, with scarce bacilli. When labelling lung suspensions for MHC-CII and classifying cells as macrophages or DC, then staining for Ziehl–Neelsen, a remarkable segregation was found regarding bacillary burden. Most macrophage-like cells contained numerous bacilli, while DC had no or scarce mycobacteria. This implies differential APC contributions in situ during pulmonary tuberculosis regarding mycobacterial uptake, granuloma involvement and perhaps bacillary growth. PMID:15255967
NASA Astrophysics Data System (ADS)
Spina, L.; Randich, S.; Magrini, L.; Jeffries, R. D.; Friel, E. D.; Sacco, G. G.; Pancino, E.; Bonito, R.; Bravi, L.; Franciosini, E.; Klutsch, A.; Montes, D.; Gilmore, G.; Vallenari, A.; Bensby, T.; Bragaglia, A.; Flaccomio, E.; Koposov, S. E.; Korn, A. J.; Lanzafame, A. C.; Smiljanic, R.; Bayo, A.; Carraro, G.; Casey, A. R.; Costado, M. T.; Damiani, F.; Donati, P.; Frasca, A.; Hourihane, A.; Jofré, P.; Lewis, J.; Lind, K.; Monaco, L.; Morbidelli, L.; Prisinzano, L.; Sousa, S. G.; Worley, C. C.; Zaggia, S.
2017-05-01
Context. The radial metallicity distribution in the Galactic thin disc represents a crucial constraint for modelling disc formation and evolution. Open star clusters allow us to derive both the radial metallicity distribution and its evolution over time. Aims: In this paper we perform the first investigation of the present-day radial metallicity distribution based on [Fe/H] determinations in late type members of pre-main-sequence clusters. Because of their youth, these clusters are therefore essential for tracing the current interstellar medium metallicity. Methods: We used the products of the Gaia-ESO Survey analysis of 12 young regions (age < 100 Myr), covering Galactocentric distances from 6.67 to 8.70 kpc. For the first time, we derived the metal content of star forming regions farther than 500 pc from the Sun. Median metallicities were determined through samples of reliable cluster members. For ten clusters the membership analysis is discussed in the present paper, while for other two clusters (I.e. Chamaeleon I and Gamma Velorum) we adopted the members identified in our previous works. Results: All the pre-main-sequence clusters considered in this paper have close-to-solar or slightly sub-solar metallicities. The radial metallicity distribution traced by these clusters is almost flat, with the innermost star forming regions having [Fe/H] values that are 0.10-0.15 dex lower than the majority of the older clusters located at similar Galactocentric radii. Conclusions: This homogeneous study of the present-day radial metallicity distribution in the Galactic thin disc favours models that predict a flattening of the radial gradient over time. On the other hand, the decrease of the average [Fe/H] at young ages is not easily explained by the models. Our results reveal a complex interplay of several processes (e.g. star formation activity, initial mass function, supernova yields, gas flows) that controlled the recent evolution of the Milky Way. Based on observations made with the ESO/VLT, at Paranal Observatory, under program 188.B-3002 (The Gaia-ESO Public Spectroscopic Survey).Full Table 1 is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/601/A70
Present-day plate motions: Retrieval from the TOPEX/Poseidon orbitography network (DORIS system)
NASA Technical Reports Server (NTRS)
Souriau, Annie; Cazenave, Anny; Biancale, R.; Balmino, G.; Dominh, K.; Mazzega, P.; Lemoine, J.-M.; Boucher, Claude; Willis, P.; Kasser, M.
1991-01-01
The goal of the proposal is to determine the present motion of the main tectonic plates from the Doppler data of the Doppler Orbitography and Radiopositioning Integrated by Satellite (DORIS) orbitography system, which includes in its final configuration about 50 tracking stations with a world-wide distribution.
NASA Astrophysics Data System (ADS)
Inglis, Robyn; Sinclair, Anthony; Fanning, Patricia; Alsharekh, Abdullah; Bailey, Geoff
2017-04-01
The vast majority of Palaeolithic archaeological material in arid and semi-arid regions exists in the form of scatters of stone tools across the surface of present-day landscapes. This is particularly the case in the Saharo-Arabian desert belt, a region vital to understanding the global dispersal of hominins from Africa. These surface artefacts possess little stratigraphic context, but comprise the only record we possess to examine spatial behavioural patterning and landscape use by hominin populations. Interpretation of the observed spatial distribution of artefacts is far from straightforward. Surface artefact distributions result from a complex interplay of varying human behaviours over time. Also, geomorphological processes affect the preservation, exposure and visibility of the artefacts, as well as alter the presence and location of attractive resources. The SURFACE project employs an interdisciplinary approach to understanding the distribution of Palaeolithic artefacts in SW Saudi Arabia. By combining remote sensing, geomorphological fieldwork, archaeological survey and GIS analyses, the project is developing a geomorphological context for the artefacts that guides survey to areas of high archaeological potential, as well as allowing the robust interpretation of the observed artefact distribution in a dynamic landscape in terms of past landscape use. This paper will present the ongoing multi-scalar approaches employed by the project to Palaeolithic landscapes, particularly focussing on the site of Wadi Dabsa, Asir Province, where Lower and Middle Palaeolithic artefacts have been found in association with extensive tufa deposits. Investigation in early 2017 at the site will apply SURFACE's methods to understand the present-day artefact distributions at the exposure, and their relationship to the tufa deposition, as well as their potential to inform on Palaeolithic activity and landscape use at the site.
Daytime distribution of Pontoporeia affinis off bottom in Lake Michigan
Wells, LaRue
1968-01-01
The vertical migration of the amphipod Pontoporeia affinis in Lake Michigan has been well documented by Wells, Marzolf, and McNaught and Hasler. Wells and Marzolf observed Pontoporeia off bottom only at night. McNaught and Hasler, however, found Pontoporeia above the bottom shortly after noon in a 24-hr study on 12 June 1965, and some individuals were taken just below the thermocline in all daylight hours in a similar study on 19-20 August. This paper presents evidence that Pontoporeia regularly were present above bottom during the day from April-August 1964. The data for this report were collected during a study of seasonal and depth distribution of larval bloaters (Coregonus hoyi) in Lake Michigan. Sampling was conducted from the U.S. Bureau of Commercial Fisheries RV Cisco off Saugatuck, Michigan, at intervals of about 10 days from 9 April to 14 August 1964. A few samples were taken on 22 August and 15 October.
Jaber, L; Kan, F W
1998-10-01
In the present study, we examined by immunohistochemistry the cell-specific distribution of epidermal growth factor (EGF) and platelet-derived growth factor (PDGF) in the mouse uterus during the oestrous cycle and throughout the first 7 days of pregnancy. Paraffin-embedded tissue samples were immunostained using the avidin-biotin peroxidase technique and then examined by light microscopy. Our results showed that immunostaining for EGF was detected in the stroma but not in the luminal or glandular epithelium. A high concentration of EGF was detected in the stroma around the time of embryo implantation at days 3, 4 and 5 of pregnancy. The implanted embryo at day 7 of gestation showed immunostaining for EGF between the ectoderm and endoderm layers. The cell distribution pattern for PDGF was found to be different from that observed with EGF. Luminal and glandular epithelia displayed PDGF immunostaining throughout the first 7 days of pregnancy, with the highest intensity at days 4 and 5 of gestation. In contrast, no immunostaining was observed in the luminal and glandular epithelia at post-oestrus, dioestrus and pro-oestrus stages. However, a weak reaction started to appear at oestrus. The embryo at the blastocyst stage displayed a strong immunoreaction for antibody against PDGF. In addition, the decidual boundary zone surrounding the implanted embryo at days 5, 6 and 7 of gestation also showed an immunostaining for PDGF. The present observations demonstrate clearly the presence of EGF and PDGF in the mouse uterus in high concentrations at the peri-implantation period. Thus, our results, together with what is known about the effect of EGF and PDGF in controlling the growth, differentiation and activation of a variety of cell types, suggest a possible role for these growth factors during the preparation of the endometrium for implantation in controlling the proliferation activity of stromal and/or epithelial cells.
The mass distribution of Population III stars
NASA Astrophysics Data System (ADS)
Fraser, M.; Casey, A. R.; Gilmore, G.; Heger, A.; Chan, C.
2017-06-01
Extremely metal-poor (EMP) stars are uniquely informative on the nature of massive Population III stars. Modulo a few elements that vary with stellar evolution, the present-day photospheric abundances observed in EMP stars are representative of their natal gas cloud composition. For this reason, the chemistry of EMP stars closely reflects the nucleosynthetic yields of supernovae from massive Population III stars. Here we collate detailed abundances of 53 EMP stars from the literature and infer the masses of their Population III progenitors. We fit a simple initial mass function (IMF) to a subset of 29 of the inferred Population III star masses, and find that the mass distribution is well represented by a power-law IMF with exponent α = 2.35^{+0.29}_{-0.24}. The inferred maximum progenitor mass for supernovae from massive Population III stars is M_{max} = 87^{+13}_{-33} M⊙, and we find no evidence in our sample for a contribution from stars with masses above ˜120 M⊙. The minimum mass is strongly consistent with the theoretical lower mass limit for Population III supernovae. We conclude that the IMF for massive Population III stars is consistent with the IMF of present-day massive stars and there may well have formed stars much below the supernova mass limit that could have survived to the present day.
NASA Astrophysics Data System (ADS)
Williams, J. E.; van der Swaluw, E.; de Vries, W. J.; Sauter, F. J.; van Pul, W. A. J.; Hoogerbrugge, R.
2015-08-01
We present a parameterization developed to simulate Ammonium particle (NH4+) concentrations in the Operational Priority Substances (OPS) source-receptor model, without the necessity of using a detailed chemical scheme. By using the ratios of the main pre-cursor gases SO2, NO2 and NH3, and utilising calculations performed using a chemical box-model, we show that the parameterization can simulate annual mean NH4+ concentration fields to within ∼15% of measured values at locations throughout the Netherlands. Performing simulations for different decades, we find a strong correlation of simulated NH4+ distributions for both past (1993-1995) and present (2009-2012) time periods. Although the total concentration of NH4+ has decreased over the period, we find that the fraction of NH4+ transported into the Netherlands has increased from around 40% in the past to 50% for present-day. This is due to the variable efficiency of mitigation practises across economic sectors. Performing simulations for the year 2020 using associated emission estimates, we show that there are generally decreases of ∼8-25% compared to present day concentrations. By altering the meteorological fields applied in the future simulations, we show that a significant uncertainty of between ∼50 and 100% exists on this estimated NH4+ distribution as a result of variability in the temperature dependent emission terms and relative humidity. Therefore, any projections of future NH4+ distributions should be performed using well chosen meteorological fields representing recent meteorological situations.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Palmintier, Bryan S; Bugbee, Bruce; Gotseff, Peter
Capturing technical and economic impacts of solar photovoltaics (PV) and other distributed energy resources (DERs) on electric distribution systems can require high-time resolution (e.g. 1 minute), long-duration (e.g. 1 year) simulations. However, such simulations can be computationally prohibitive, particularly when including complex control schemes in quasi-steady-state time series (QSTS) simulation. Various approaches have been used in the literature to down select representative time segments (e.g. days), but typically these are best suited for lower time resolutions or consider only a single data stream (e.g. PV production) for selection. We present a statistical approach that combines stratified sampling and bootstrapping tomore » select representative days while also providing a simple method to reassemble annual results. We describe the approach in the context of a recent study with a utility partner. This approach enables much faster QSTS analysis by simulating only a subset of days, while maintaining accurate annual estimates.« less
Comparison of Wind Power and Load Forecasting Error Distributions: Preprint
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hodge, B. M.; Florita, A.; Orwig, K.
2012-07-01
The introduction of large amounts of variable and uncertain power sources, such as wind power, into the electricity grid presents a number of challenges for system operations. One issue involves the uncertainty associated with scheduling power that wind will supply in future timeframes. However, this is not an entirely new challenge; load is also variable and uncertain, and is strongly influenced by weather patterns. In this work we make a comparison between the day-ahead forecasting errors encountered in wind power forecasting and load forecasting. The study examines the distribution of errors from operational forecasting systems in two different Independent Systemmore » Operator (ISO) regions for both wind power and load forecasts at the day-ahead timeframe. The day-ahead timescale is critical in power system operations because it serves the unit commitment function for slow-starting conventional generators.« less
Miedema, H M; Oudshoorn, C G
2001-01-01
We present a model of the distribution of noise annoyance with the mean varying as a function of the noise exposure. Day-night level (DNL) and day-evening-night level (DENL) were used as noise descriptors. Because the entire annoyance distribution has been modeled, any annoyance measure that summarizes this distribution can be calculated from the model. We fitted the model to data from noise annoyance studies for aircraft, road traffic, and railways separately. Polynomial approximations of relationships implied by the model for the combinations of the following exposure and annoyance measures are presented: DNL or DENL, and percentage "highly annoyed" (cutoff at 72 on a scale of 0-100), percentage "annoyed" (cutoff at 50 on a scale of 0-100), or percentage (at least) "a little annoyed" (cutoff at 28 on a scale of 0-100). These approximations are very good, and they are easier to use for practical calculations than the model itself, because the model involves a normal distribution. Our results are based on the same data set that was used earlier to establish relationships between DNL and percentage highly annoyed. In this paper we provide better estimates of the confidence intervals due to the improved model of the relationship between annoyance and noise exposure. Moreover, relationships using descriptors other than DNL and percentage highly annoyed, which are presented here, have not been established earlier on the basis of a large dataset. PMID:11335190
Distribution of radionuclides in the environment in northern Italy after the Chernobyl accident.
Berzero, A; Borroni, P A; Oddone, M; Crespi, V C; Genova, N; Meloni, S
1992-03-01
Soon after the Chernobyl nuclear accident, the air-pumping stations in Pavia (northern Italy) were alerted. In a few days, a rapid increase in radionuclide concentration in air particulates was observed. Consequently, an environmental radioactivity monitoring programme was started in which several matrices such as soil, grass, vegetables and cows' milk were subjected to direct gamma-ray spectrometry. The radioactivity distribution and its variation with time is presented, discussed and compared with other available data. Detection limits, precision and accuracy are also reported, and depth profiles in soils for 137Cs are presented and correlated with soil quality parameters. A survey of environmental radioactivity in soil, in a search for residual Chernobyl fallout, was carried out and a map of the 137Cs distribution over a large area in northern Italy is presented and discussed.
NASA Technical Reports Server (NTRS)
Shindell, Drew T.; Grenfell, J. Lee; Rind, David; Price, Colin; Grewe, Volker; Hansen, James E. (Technical Monitor)
2001-01-01
A tropospheric chemistry module has been developed for use within the Goddard Institute for Space Studies (GISS) general circulation model (GCM) to study interactions between chemistry and climate change. The model uses a simplified chemistry scheme based on CO-NOx-CH4 chemistry, and also includes a parameterization for emissions of isoprene, the most important non-methane hydrocarbon. The model reproduces present day annual cycles and mean distributions of key trace gases fairly well, based on extensive comparisons with available observations. Examining the simulated change between present day and pre-industrial conditions, we find that the model has a similar response to that seen in other simulations. It shows a 45% increase in the global tropospheric ozone burden, within the 25% - 57% range seen in other studies. Annual average zonal mean ozone increases by more than 125% at Northern Hemisphere middle latitudes near the surface. Comparison of model runs that allow the calculated ozone to interact with the GCM's radiation and meteorology with those that do not shows only minor differences for ozone. The common usage of ozone fields that are not calculated interactively seems to be adequate to simulate both the present day and the pre-industrial ozone distributions. However, use of coupled chemistry does alter the change in tropospheric oxidation capacity, enlarging the overall decrease in OH concentrations from the pre-industrial to the present by about 10% (-5.3% global annual average in uncoupled mode, -5.9% in coupled mode). This indicates that there may be systematic biases in the simulation of the pre-industrial to present day decrease in the oxidation capacity of the troposphere (though a 10% difference is well within the total uncertainty). Global annual average radiative forcing from pre-industrial to present day ozone change is 0.32 W/sq m. The forcing seems to be increased by about 10% when the chemistry is coupled to the GCM. Forcing values greater than 0.8 W/sq m are seen over large areas of the United States, Southern Europe, North Africa, the Middle East, Central Asia, and the Arctic. Radiative forcing is greater than 1.5 W/sq m over parts of these areas during Northern summer Though there are local differences, the radiative forcing is overall in good agreement with the results of other modeling studies in both its magnitude and spatial distribution, demonstrating that the simplified chemistry is adequate for climate studies.
Verdaasdonk, E G G; Stassen, L P S; van Wijk, R P J; Dankelman, J
2007-02-01
Psychomotor skills for endoscopic surgery can be trained with virtual reality simulators. Distributed training is more effective than massed training, but it is unclear whether distributed training over several days is more effective than distributed training within 1 day. This study aimed to determine which of these two options is the most effective for training endoscopic psychomotor skills. Students with no endoscopic experience were randomly assigned either to distributed training on 3 consecutive days (group A, n = 10) or distributed training within 1 day (group B, n = 10). For this study the SIMENDO virtual reality simulator for endoscopic skills was used. The training involved 12 repetitions of three different exercises (drop balls, needle manipulation, 30 degree endoscope) in differently distributed training schedules. All the participants performed a posttraining test (posttest) for the trained tasks 7 days after the training. The parameters measured were time, nontarget environment collisions, and instrument path length. There were no significant differences between the groups in the first training session for all the parameters. In the posttest, group A (training over several days) performed 18.7% faster than group B (training on 1 day) (p = 0.013). The collision and path length scores for group A did not differ significantly from the scores for group B. The distributed group trained over several days was faster, with the same number of errors and the same instrument path length used. Psychomotor skill training for endoscopic surgery distributed over several days is superior to training on 1 day.
Horn, B J; Lake, R J
2013-10-03
Differentiation between travel-related and domestic cases of infectious disease is important in managing risk. Incubation periods of cases from several outbreaks of campylobacteriosis in Canada, Europe, and the United States with defined exposure time of less than 24 hours were collated to provide information on the incubation period distribution. This distribution was consistent across the varied outbreaks considered, with 84% (702/832) of cases having an incubation period of four days or less and 1% having an incubation period of eight days or more. The incubation period distribution was incorporated into a model for the number of travel-related cases presenting with symptom onset at given dates after return to their country of residence. Using New Zealand notification data between 2006 and 2010 for cases who had undertaken foreign travel within 10 days prior to symptom onset, we found that 29.6% (67/227 cases; 95% confidence interval (CI): 28.3–30.8%) of these cases were likely to have been domestic cases. When cases with symptom onset prior to arrival were included, the probable domestic cases represented 11.8% (67/571; 95% CI: 11.2–12.3%). Consideration of incubation time distributions and consistent collection of travel start/end dates with symptom onset dates would assist attribution of cases to foreign travel.
Tojinbara, Kageaki; Sugiura, K; Yamada, A; Kakitani, I; Kwan, N C L; Sugiura, K
2016-01-01
Data of 98 rabies cases in dogs and cats from the 1948-1954 rabies epidemic in Tokyo were used to estimate the probability distribution of the incubation period. Lognormal, gamma and Weibull distributions were used to model the incubation period. The maximum likelihood estimates of the mean incubation period ranged from 27.30 to 28.56 days according to different distributions. The mean incubation period was shortest with the lognormal distribution (27.30 days), and longest with the Weibull distribution (28.56 days). The best distribution in terms of AIC value was the lognormal distribution with mean value of 27.30 (95% CI: 23.46-31.55) days and standard deviation of 20.20 (15.27-26.31) days. There were no significant differences between the incubation periods for dogs and cats, or between those for male and female dogs. Copyright © 2015 Elsevier B.V. All rights reserved.
The ‘hit’ phenomenon: a mathematical model of human dynamics interactions as a stochastic process
NASA Astrophysics Data System (ADS)
Ishii, Akira; Arakaki, Hisashi; Matsuda, Naoya; Umemura, Sanae; Urushidani, Tamiko; Yamagata, Naoya; Yoshida, Narihiko
2012-06-01
A mathematical model for the ‘hit’ phenomenon in entertainment within a society is presented as a stochastic process of human dynamics interactions. The model uses only the advertisement budget time distribution as an input, and word-of-mouth (WOM), represented by posts on social network systems, is used as data to make a comparison with the calculated results. The unit of time is days. The WOM distribution in time is found to be very close to the revenue distribution in time. Calculations for the Japanese motion picture market based on the mathematical model agree well with the actual revenue distribution in time.
Daylight operation of a free space, entanglement-based quantum key distribution system
NASA Astrophysics Data System (ADS)
Peloso, Matthew P.; Gerhardt, Ilja; Ho, Caleb; Lamas-Linares, Antía; Kurtsiefer, Christian
2009-04-01
Many quantum key distribution (QKD) implementations using a free space transmission path are restricted to operation at night time in order to distinguish the signal photons used for a secure key establishment from the background light. Here, we present a lean entanglement-based QKD system overcoming that limitation. By implementing spectral, spatial and temporal filtering techniques, we establish a secure key continuously over several days under varying light and weather conditions.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
The following appendices to volume I are presented: biomass of dominant microzooplankton; biomass of zooplankton in surface waters of Jobos Bay; comparison of zooplankton caught during day and night; variations in surface temperature and salinity at collection sites; distance, depth, and temperature related to dominant vegetation and sea grass; total biomass of Thalassia testudium; photosynthetic pigment diversity; invertebrate species and frequency of occurrence; distribution of macrobenthic organisms; species found on mangrove roots; distribution of fish species; and seasonal occurrence of fish species. (HLW)
In Situ Metrology for the Corrective Polishing of Replicating Mandrels
2010-06-08
distribution is unlimited. 13. SUPPLEMENTARY NOTES Presented at Mirror Technology Days, Boulder, Colorado, USA, 7-9 June 2010. 14...ABSTRACT The International X-ray Observatory (IXO) will require mandrel metrology with extremely tight tolerances on mirrors with up to 1.6 meter radii...ideal. Error budgets for the IXO mirror segments are presented. A potential solution is presented that uses a voice-coil controlled gauging head, air
Endothelial nitric oxide synthase in hypoxic newborn porcine pulmonary vessels
Hislop, A; Springall, D; Oliveira, H; Pollock, J; Polak, J; Haworth, S
1997-01-01
AIMS—To determine if the failure of neonatal pulmonary arteries to dilate is due to a lack of nitric oxide synthase (NOS). METHODS—A monoclonal antibody to endothelial NOS was used to demonstrate the distribution and density of NOS in the developing porcine lung after a period in hypobaric hypoxia. Newborn piglets were made hypertensive by exposure to hypobaric hypoxia (50.8 kPa) from < 5 minutes of age to 2.5 days of age, 3-6 days of age or 14-17 days of age. A semiquantitative scoring system was used to assess the distribution of endothelial NOS by light microscopy. RESULTS—NOS was present in the arteries in all hypoxic animals. However, hypoxia from birth caused a reduction in NOS compared with those lungs normal at birth and those normal at 3 days. Hypoxia from 3-6 days led to a high density of NOS compared with normal lungs at 6 days. Hypoxia from 14-17 days had little effect on the amount of NOS. On recovery in room air after exposure to hypoxia from birth there was a transient increase in endothelial NOS after three days of recovery, mirroring that seen at three days in normal animals. CONCLUSIONS—Suppression of NOS production in the first few days of life may contribute to pulmonary hypertension in neonates. Keywords: pulmonary circulation; nitric oxide synthase; hypoxia; endothelium; piglets PMID:9279177
Palumbo, R. Noelle; Zhong, Xiao; Panus, David; Han, Wenqing; Ji, Weihang; Wang, Chun
2012-01-01
DNA vaccination using cationic polymers as carriers has the potential to be a very powerful method of immunotherapy, but typical immune responses generated have been less than robust. To better understand the details of DNA vaccine delivery in vivo, we prepared polymer/DNA complexes using three structurally distinct cationic polymers and fluorescently labeled plasmid DNA and injected them intradermally into mice. We analyzed transgene expression (luciferase) and the local tissue distribution of the labeled plasmid at the injection site at various time points (from hours to days). Comparable numbers of luciferase expressing cells were observed in the skin of mice receiving naked plasmid or polyplexes one day after transfection. At day 4, however, the polyplexes appeared to result in more transfected skin cells than naked plasmid. Live animal imaging revealed that naked plasmid dispersed quickly in the skin of mice after injection and had a wider distribution than any of the three types of polyplexes. However, naked plasmid level dropped to below detection limit after 24 h, whereas polyplexes persisted for up to 2 weeks. The PEGylated polyplexes had a significantly wider distribution in the tissue than the nonPEGylated polyplexes. PEGylated polyplexes also distributed more broadly among dermal fibroblasts and allowed greater interaction with antigen-presenting cells (APCs) (dendritic cells and macrophages) starting at around 24 h post-injection. By day 4, co-localization of polyplexes with APCs was observed at the injection site regardless of polymer structure, whereas small amounts of polyplexes were found in the draining lymph nodes. These in vivo findings demonstrate the superior stability of PEGylated polyplexes in physiological milieu and provide important insight on how cationic polymers could be optimized for DNA vaccine delivery. PMID:22300619
Laugesen, Kristina; Støvring, Henrik; Hallas, Jesper; Pottegård, Anton; Jørgensen, Jens Otto Lunde; Sørensen, Henrik Toft; Petersen, Irene
2017-01-01
Glucocorticoids are widely used medications. In many pharmacoepidemiological studies, duration of individual prescriptions and definition of treatment episodes are important issues. However, many data sources lack this information. We aimed to estimate duration of individual prescriptions for oral glucocorticoids and to describe continuous treatment episodes using the parametric waiting time distribution. We used Danish nationwide registries to identify all prescriptions for oral glucocorticoids during 1996-2014. We applied the parametric waiting time distribution to estimate duration of individual prescriptions each year by estimating the 80th, 90th, 95th and 99th percentiles for the interarrival distribution. These corresponded to the time since last prescription during which 80%, 90%, 95% and 99% of users presented a new prescription for redemption. We used the Kaplan-Meier survival function to estimate length of first continuous treatment episodes by assigning estimated prescription duration to each prescription and thereby create treatment episodes from overlapping prescriptions. We identified 5,691,985 prescriptions issued to 854,429 individuals of whom 351,202 (41%) only redeemed 1 prescription in the whole study period. The 80th percentile for prescription duration ranged from 87 to 120 days, the 90th percentile from 116 to 150 days, the 95th percentile from 147 to 181 days, and the 99th percentile from 228 to 259 days during 1996-2014. Based on the 80th, 90th, 95th and 99th percentiles of prescription duration, the median length of continuous treatment was 113, 141, 170 and 243 days, respectively. Our method and results may provide an important framework for future pharmacoepidemiological studies. The choice of which percentile of the interarrival distribution to apply as prescription duration has an impact on the level of misclassification. Use of the 80th percentile provides a measure of drug exposure that is specific, while the 99th percentile provides a sensitive measure.
NASA Astrophysics Data System (ADS)
Sousa, Fernanda; Mandal, Subhra; Garrovo, Chiara; Astolfo, Alberto; Bonifacio, Alois; Latawiec, Diane; Menk, Ralf Hendrik; Arfelli, Fulvia; Huewel, Sabine; Legname, Giuseppe; Galla, Hans-Joachim; Krol, Silke
2010-12-01
In the present study, the in vivo distribution of polyelectrolyte multilayer coated gold nanoparticles is shown, starting from the living animal down to cellular level. The coating was designed with functional moieties to serve as a potential nano drug for prion disease. With near infrared time-domain imaging we followed the biodistribution in mice up to 7 days after intravenous injection of the nanoparticles. The peak concentration in the head of mice was detected between 19 and 24 h. The precise particle distribution in the brain was studied ex vivo by X-ray microtomography, confocal laser and fluorescence microscopy. We found that the particles mainly accumulate in the hippocampus, thalamus, hypothalamus, and the cerebral cortex.In the present study, the in vivo distribution of polyelectrolyte multilayer coated gold nanoparticles is shown, starting from the living animal down to cellular level. The coating was designed with functional moieties to serve as a potential nano drug for prion disease. With near infrared time-domain imaging we followed the biodistribution in mice up to 7 days after intravenous injection of the nanoparticles. The peak concentration in the head of mice was detected between 19 and 24 h. The precise particle distribution in the brain was studied ex vivo by X-ray microtomography, confocal laser and fluorescence microscopy. We found that the particles mainly accumulate in the hippocampus, thalamus, hypothalamus, and the cerebral cortex. Electronic supplementary information (ESI) available: Fig. S1-S6. See DOI: 10.1039/c0nr00345j
Peterson, A Townsend; Campbell, Lindsay P; Moo-Llanes, David A; Travi, Bruno; González, Camila; Ferro, María Cristina; Ferreira, Gabriel Eduardo Melim; Brandão-Filho, Sinval P; Cupolillo, Elisa; Ramsey, Janine; Leffer, Andreia Mauruto Chernaki; Pech-May, Angélica; Shaw, Jeffrey J
2017-09-01
This study explores the present day distribution of Lutzomyia longipalpis in relation to climate, and transfers the knowledge gained to likely future climatic conditions to predict changes in the species' potential distribution. We used ecological niche models calibrated based on occurrences of the species complex from across its known geographic range. Anticipated distributional changes varied by region, from stability to expansion or decline. Overall, models indicated no significant north-south expansion beyond present boundaries. However, some areas suitable both at present and in the future (e.g., Pacific coast of Ecuador and Peru) may offer opportunities for distributional expansion. Our models anticipated potential range expansion in southern Brazil and Argentina, but were variably successful in anticipating specific cases. The most significant climate-related change anticipated in the species' range was with regard to range continuity in the Amazon Basin, which is likely to increase in coming decades. Rather than making detailed forecasts of actual locations where Lu. longipalpis will appear in coming years, our models make interesting and potentially important predictions of broader-scale distributional tendencies that can inform heath policy and mitigation efforts. Copyright © 2017 Australian Society for Parasitology. Published by Elsevier Ltd. All rights reserved.
Surface ozone in China: present-day distribution and long-term changes
NASA Astrophysics Data System (ADS)
Xu, X.; Lin, W.; Xu, W.
2017-12-01
Reliable knowledge of spatio-temporal variations of surface ozone is highly needed to assess the impacts of ozone on human health, ecosystem and climate. Although regional distributions and trends of surface ozone in European and North American countries have been well characterized, little is known about the variability of surface ozone in many other countries, including China, where emissions of ozone precursors have been changing rapidly in recent decades. Here we present the first comprehensive description of present-day (2013-2017) distribution and long-term changes of surface ozone in mainland China. Recent ozone measurements from China's air quality monitoring network (AQMN) are analyzed to show present-day distributions of a few ozone exposure metrics for urban environment. Long-term measurements of ozone at six background sites, a rural site and an urban are used to study the trends of ozone in background, rural and urban air, respectively. The average levels of ozone at the AQMN sites (mainly urban) are close to those found at many European and North American sites. However, ozone at most of the sites shows very large diurnal and seasonal variations so that ozone nonattainment can occur in many cities, particularly those in the North China Plain (NCP), the south of Northeast China (NEC), the Yangtze River Delta (YRD), the Pearl River Delta (PRD), and the Sichuan Basin-Chongqing region (SCB). In all these regions, particularly in the NCP, the maximum daily 8-h average (MDA8) ozone concentration can significantly exceed the national limit (75 ppb). High annual sum of ozone means over 35 ppb (SOMO35) exist mainly in the NCP, NEC and YRD, with regional averages over 4000 ppb·d. Surface ozone has significantly increased at Waliguan (a baseline site in western China) and Shangdianzi (a background site in the NCP), and decreased in winter and spring at Longfengshan (a background site in Northeast China). No clear trend can be derived from long-term measurements of ozone at other sites. Further attention should be paid to future changes of ozone in populated regions of China. Actions are urgently needed to control ozone pollution in the NCP and YRD.
NASA Astrophysics Data System (ADS)
Braun, Jean; Gemignani, Lorenzo; van der Beek, Peter
2018-03-01
One of the main purposes of detrital thermochronology is to provide constraints on the regional-scale exhumation rate and its spatial variability in actively eroding mountain ranges. Procedures that use cooling age distributions coupled with hypsometry and thermal models have been developed in order to extract quantitative estimates of erosion rate and its spatial distribution, assuming steady state between tectonic uplift and erosion. This hypothesis precludes the use of these procedures to assess the likely transient response of mountain belts to changes in tectonic or climatic forcing. Other methods are based on an a priori knowledge of the in situ distribution of ages to interpret the detrital age distributions. In this paper, we describe a simple method that, using the observed detrital mineral age distributions collected along a river, allows us to extract information about the relative distribution of erosion rates in an eroding catchment without relying on a steady-state assumption, the value of thermal parameters or an a priori knowledge of in situ age distributions. The model is based on a relatively low number of parameters describing lithological variability among the various sub-catchments and their sizes and only uses the raw ages. The method we propose is tested against synthetic age distributions to demonstrate its accuracy and the optimum conditions for it use. In order to illustrate the method, we invert age distributions collected along the main trunk of the Tsangpo-Siang-Brahmaputra river system in the eastern Himalaya. From the inversion of the cooling age distributions we predict present-day erosion rates of the catchments along the Tsangpo-Siang-Brahmaputra river system, as well as some of its tributaries. We show that detrital age distributions contain dual information about present-day erosion rate, i.e., from the predicted distribution of surface ages within each catchment and from the relative contribution of any given catchment to the river distribution. The method additionally allows comparing modern erosion rates to long-term exhumation rates. We provide a simple implementation of the method in Python code within a Jupyter Notebook that includes the data used in this paper for illustration purposes.
NASA Astrophysics Data System (ADS)
Bout-Roumazeilles, V.; Riboulleau, A.; du Châtelet, E. Armynot; Lorenzoni, L.; Tribovillard, N.; Murray, R. W.; Müller-Karger, F.; Astor, Y. M.
2013-02-01
The mineralogical composition of 95 surface sediment samples from the Cariaco Basin continental shelf and Orinoco delta was investigated in order to constrain the clay-mineral main provenance and distribution within the Cariaco Basin. The spatial variability of the data set was studied using a geo-statistical approach that allows drawing representative clay-mineral distribution maps. These maps are used to identify present-day dominant sources for each clay-mineral species in agreement with the geological characteristics of the main river watersheds emptying into the basin. This approach allows (1) identifying the most distinctive clay-mineral species/ratios that determine particle provenance, (2) evaluating the respective contribution of local rivers, and (3) confirming the minimal present-day influence of the Orinoco plume on the Cariaco Basin sedimentation. The Tuy, Unare, and Neveri Rivers are the main sources of clay particles to the Cariaco Basin sedimentation. At present, the Tuy River is the main contributor of illite to the western part of the southern Cariaco Basin continental shelf. The Unare River plume, carrying smectite and kaolinite, has a wide westward propagation, whereas the Neveri River contribution is less extended, providing kaolinite and illite toward the eastern Cariaco Basin. The Manzanares, Araya, Tortuga, and Margarita areas are secondary sources of local influence. These insights shed light on the origin of present-day terrigenous sediments of the Cariaco Basin and help to propose alternative explanations for the temporal variability of clay mineralogy observed in previously published studies.
Zhou, Sihui; Zhang, Caiying; Xiao, Qingyang; Zhuang, Yu; Gu, Xiaolong; Yang, Fan; Xing, Chenghong; Hu, Guoliang; Cao, Huabin
2016-11-01
Molybdenum (Mo) is an essential trace element for animals and human beings. However, the negative effects on rumen function and distribution of trace elements in tissues induced by excessive Mo have not been well understood. Therefore, the purpose of present study was to investigate the impact of Mo on rumen microbiota, distribution of trace elements in various organs, and hematological parameters of goats. A total of 36 goats were randomly distributed into three groups with equal number and low-Mo and high-Mo groups were orally administered ammonium molybdate at 15 and 45 mg · Mo · kg -1 · BW respectively, while the control group received corresponding quantitative deionized water. The results showed that the total number of ciliate and protozoa protein concentration decreased significantly (P < 0.01) on days 25 and 50. Concentrations of ammonia nitrogen and bacterial protein were significantly higher (P < 0.05) in low-Mo group, while they were lower (P < 0.05) in high-Mo group than the control group on days 25 and 50. In addition, Mo accumulated in serum and all detected tissues. Copper (Cu) and zinc (Zn) contents significantly decreased (P < 0.05) in hair and serum on days 25 and 50, while Cu contents increased (P < 0.05) and the change of Zn contents were not obvious (P > 0.05) in other tissues on days 25 and 50. Besides, there was no obvious variation in iron (Fe) contents during whole experiment period (P > 0.05). Furthermore, excessive Mo content had no significant effect on red blood cell (RBC) counts and hemoglobin (HGB) concentration (P > 0.05) on days 25 and 50, while white blood cell (WBC) counts increased significantly (P < 0.05) on day 50. These results indicated that excessive Mo content could impact the balance of ruminal microorganisms and interfere with the absorption and distribution of Mo and Cu mainly.
Hartley, Stephen; Krushelnycky, Paul D.; Lester, Philip J.
2010-01-01
Mechanistic models for predicting species’ distribution patterns present particular advantages and challenges relative to models developed from statistical correlations between distribution and climate. They can be especially useful for predicting the range of invasive species whose distribution has not yet reached equilibrium. Here, we illustrate how a physiological model of development for the invasive Argentine ant can be connected to differences in micro-site suitability, population dynamics and climatic gradients; processes operating at quite different spatial scales. Our study is located in the subalpine shrubland of Haleakala National Park, Hawaii, where the spread of Argentine ants Linepithema humile has been documented for the past twenty-five years. We report four main results. First, at a microsite level, the accumulation of degree-days recorded in potential ant nest sites under bare ground or rocks was significantly greater than under a groundcover of grassy vegetation. Second, annual degree-days measured where population boundaries have not expanded (456-521 degree-days), were just above the developmental requirements identified from earlier laboratory studies (445 degree-days above 15.98C). Third, rates of population expansion showed a strong linear relationship with annual degree-days. Finally, an empirical relationship between soil degree-days and climate variables mapped at a broader scale predicts the potential for future range expansion of Argentine ants at Haleakala, particularly to the west of the lower colony and the east of the upper colony. Variation in the availability of suitable microsites, driven by changes in vegetation cover and ultimately climate, provide a hierarchical understanding of the distribution of Argentine ants close to their cold-wet limit of climatic tolerances. We conclude that the integration of physiology, population dynamics and climate mapping holds much promise for making more robust predictions about the potential spread of invasive species.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Khangarot, B.S.; Takroo, R.; Singh, R.R.
1991-12-01
The current study was undertaken to determine the sublethal toxicity of commercial grade hexachlorocyclohexane (HCH) to a freshwater air-breathing catfish, Saccobranchus fossilis (Bloch) for 14 days. The bioconcentration of HCH and its distribution in gill, brain and liver was determined. This species was selected for the present study because it is widely distributed in ponds, lakes and rivers of India and consumed as human diet in many parts of the world.
Kinetics of humoral responsiveness and antigenic distribution in operated rats.
Kinnaert, P; Mahieu, A; van Geertruyden, N
1979-01-01
Wistar R/A rats were injected intravenously with 10(9) sheep red blood cells (SRBC) prior to, during or after a standard laparotomy. Stimulation of anti-SRBC antibody synthesis was already observed when the antigen was given 4 h prior to surgery and was maximal if SRBC were administered at the time of operation. The enhancing effect on the immune response lasted for 2 days after surgery. From the third post-operative day on, the injection of SRBC induced a normal humoral response. No subsequent depression was detected. Inter-organ distribution studies of 51Cr-labelled SRBC injected at various times prior, during or after the surgical procedure, showed a maximum decrease of liver uptake during operation; the depression was still present 2 h later but on the first post-operative day, no significant difference from the controls could be demonstrated. When the labelled antigen was given before surgery, organ distribution was normal. Consequently, there is no time relationship between the stimulation of antibody production and the alteration of total phagocytosis induced by surgery. Therefore, the enhanced humoral response cannot be explained only by spillover of the antigen from the liver into lymphoid organs. PMID:511217
Non-uniform Solar Temperature Field on Large Aperture, Fully-Steerable Telescope Structure
NASA Astrophysics Data System (ADS)
Liu, Yan
2016-09-01
In this study, a 110-m fully steerable radio telescope was used as an analysis platform and the integral parametric finite element model of the antenna structure was built in the ANSYS thermal analysis module. The boundary conditions of periodic air temperature, solar radiation, long-wave radiation shadows of the surrounding environment, etc. were computed at 30 min intervals under a cloudless sky on a summer day, i.e., worstcase climate conditions. The transient structural temperatures were then analyzed under a period of several days of sunshine with a rational initial structural temperature distribution until the whole set of structural temperatures converged to the results obtained the day before. The non-uniform temperature field distribution of the entire structure and the main reflector surface RMS were acquired according to changes in pitch and azimuth angle over the observation period. Variations in the solar cooker effect over time and spatial distributions in the secondary reflector were observed to elucidate the mechanism of the effect. The results presented here not only provide valuable realtime data for the design, construction, sensor arrangement and thermal deformation control of actuators but also provide a troubleshooting reference for existing actuators.
Peters, K.E.; Bird, K.J.; Keller, M.A.; Lillis, P.G.; Magoon, L.B.
2003-01-01
Four source rock units on the North Slope were identified, characterized, and mapped to better understand the origin of petroleum in the area: Hue-gamma ray zone (Hue-GRZ), pebble shale unit, Kingak Shale, and Shublik Formation. Rock-Eval pyrolysis, total organic carbon analysis, and well logs were used to map the present-day thickness, organic quantity (TOC), quality (hydrogen index, HI), and thermal maturity (Tmax) of each unit. To map these units, we screened all available geochemical data for wells in the study area and assumed that the top and bottom of the oil window occur at Tmax of ~440° and 470°C, respectively. Based on several assumptions related to carbon mass balance and regional distributions of TOC, the present-day source rock quantity and quality maps were used to determine the extent of fractional conversion of the kerogen to petroleum and to map the original organic richness prior to thermal maturation.
Climate change and marine ecosystems (Invited)
NASA Astrophysics Data System (ADS)
Chavez, F.
2013-12-01
Impacts of climate variability on marine ecosystems are pervasive. Those associated with the interannual El Ni~no phenomena are the most studied and better understood. Longer term variations associated with the Atlantic Multidecadal Oscillation (AMO), the Pacific Decadal Oscillation (PDO) and the North Pacific Gyre Oscillation (NPGO) have become more evident as the present-day instrumental record has increased in length. The biological (chlorophyll to fish) and chemical (nutrients, oxygen, carbon) consequences of these climate-driven variations are discussed with an emphasis on the eastern and equatorial Pacific. During warmer periods biological productivity in the eastern Pacific is reduced and larger mobile organisms dramatically change their abundance and/or geographic distributions. At the same time biological productivity in the western Pacific increases highlighting that present (and future) climate-driven changes in biological productivity and chemical distributions are not (and will not) be uniform. The presentation documents present day variations using global scale information from satellites and in situ databases, model simulations and data collected by intensive local time series. Paradoxically longer term changes associated with phenomena like the Little Ice Age (LIA), captured in the sedimentary record, do not seem to follow the same warm (poor), cold (productive) patterns in the eastern Pacific, in fact these are reversed. The presentation ends with speculation regarding long term changes associated with a warmer world.
Mesoscale mapping of available solar energy at the earth's surface by use of satellites
NASA Technical Reports Server (NTRS)
Hiser, H. W.; Senn, H. V.
1980-01-01
A method is presented for use of cloud images in the visual spectrum from the SMS/GOES geostationary satellites to determine the hourly distribution of sunshine on the mesoscale. Cloud coverage and density as a function of time of day and season are evaluated through the use of digital data processing techniques. Seasonal geographic distributions of cloud cover/sunshine are converted to joules of solar radiation received at the earth's surface through relationships developed from long-term measurements of these two parameters at six widely distributed stations. The technique can be used to generate maps showing the geographic distribution of total solar radiation on the mesoscale which is received at the earth's surface.
Rich D. Koehler; Keith I. Kelson; Graham Matthews; K.H. Kang; Andrew D. Barron
2007-01-01
The South Fork Noyo River (SFNR) watershed in coastal northern California contains large volumes of historic sediment that were delivered to channels in response to past logging operations. This sediment presently is stored beneath historic terraces and in present-day channels. We conducted geomorphic mapping on the SFNR valley floor to assess the volume and location...
Variety of Behavior of Equity Returns in Financial Markets
NASA Astrophysics Data System (ADS)
Bonanno, Giovanni; Lillo, Fabrizio; Mantegna, Rosario N.
2001-03-01
The price dynamics of a set of equities traded in an efficient market is pretty complex. It consists of almost not redundant time series which have (i) long-range correlated volatility and (ii) cross-correlation between each pair of equities. We perform a study of the statistical properties of an ensemble of equities returns which is fruitful to elucidate the nature and role of time and ensemble correlation. Specifically, we investigate a statistical ensemble of daily returns of n equities traded in United States financial markets. For each trading day of our database, we study the ensemble return distribution. We find that a typical ensemble return distribution exists in most of the trading days [1] with the exception of crash and rally days and of the days following to these extreme events [2]. We analyze each ensemble return distribution by extracting its first two central moments. We call the second moment of the ensemble return distribution the variety of the market. We choose this term because high variety implies a variated behavior of the equities returns in the considered day. We observe that the mean return and the variety are fluctuating in time and are stochastic processes themselves. The variety is a long-range correlated stochastic process. Customary time-averaged statistical properties of time series of stock returns are also considered. In general, time-averaged and portfolio-averaged returns have different statistical properties [1]. We infer from these differences information about the relative strength of correlation between equities and between different trading days. We also compare our empirical results with those predicted by the single-index model and we conclude that this simple model is unable to explain the statistical properties of the second moment of the ensemble return distribution. Correlation between pairs of equities are continuously present in the dynamics of a stock portfolio. Hence, it is relevant to investigate pair correlation in a efficient and original way. We propose to investigate these correlations at a daily and intra daily time horizon with a method based on concepts of random frustrated systems. Specifically, a hierarchical organization of the investigated equities is obtained by determining a metric distance between stocks and by investigating the properties of the subdominant ultrametric associated with it [3]. The high-frequency cross-correlation existing between pairs of equities are investigated in a set of 100 stocks traded in US equity markets. The decrease of the cross-correlation between the equity returns observed for diminishing time horizons progressively changes the nature of the hierarchical structure associated to each different time horizon [4]. The nature of the correlation present between pairs of time series of equity returns collected in a portfolio has a strong influence on the variety of the market. We finally discuss the relation between pair correlation and variety of an ensemble return distribution. References [1] Fabrizio Lillo and Rosario N. Mantegna, Variety and volatility in financial markets, Phys. Rev. E 62, 6126-6134 (2000). [2] Fabrizio Lillo and Rosario N. Mantegna, Symmetry alteration of ensemble return distribution in crash and rally days of financial market, Eur. Phys. J. B 15, 603-606 (2000). [3] Rosario N. Mantegna, Hierarchical structure in financial markets, Eur. Phys. J. B 11, 193-197 (1999). [4] Giovanni Bonanno, Fabrizio Lillo, and Rosario N. Mantegna, High-frequency cross-correlation in a set of stocks, Quantitative Finance (in press).
Phase distribution of spliceosomal introns: implications for intron origin
Nguyen, Hung D; Yoshihama, Maki; Kenmochi, Naoya
2006-01-01
Background The origin of spliceosomal introns is the central subject of the introns-early versus introns-late debate. The distribution of intron phases is non-uniform, with an excess of phase-0 introns. Introns-early explains this by speculating that a fraction of present-day introns were present between minigenes in the progenote and therefore must lie in phase-0. In contrast, introns-late predicts that the nonuniformity of intron phase distribution reflects the nonrandomness of intron insertions. Results In this paper, we tested the two theories using analyses of intron phase distribution. We inferred the evolution of intron phase distribution from a dataset of 684 gene orthologs from seven eukaryotes using a maximum likelihood method. We also tested whether the observed intron phase distributions from 10 eukaryotes can be explained by intron insertions on a genome-wide scale. In contrast to the prediction of introns-early, the inferred evolution of intron phase distribution showed that the proportion of phase-0 introns increased over evolution. Consistent with introns-late, the observed intron phase distributions matched those predicted by an intron insertion model quite well. Conclusion Our results strongly support the introns-late hypothesis of the origin of spliceosomal introns. PMID:16959043
DOE Office of Scientific and Technical Information (OSTI.GOV)
Aleshin, S. S., E-mail: aless2001@mail.ru; Lobanov, A. E., E-mail: lobanov@phys.msu.ru; Kharlanov, O. G., E-mail: okharl@mail.ru
The effect of flavor day-night asymmetry is considered for solar neutrinos of energy about 1 MeV under the assumption that the electron-density distribution within the Earth is approximately piecewise continuous on the scale of the neutrino-oscillation length. In this approximation, the resulting asymmetry factor for beryllium neutrinos does not depend on the structure of the inner Earth's layers or on the properties of the detector used. Its numerical estimate is on the order of -4 Multiplication-Sign 10{sup -4}, which is far beyond the reach of present-day experiments.
Chronobiology of Takotsubo Syndrome and Myocardial Infarction: Analogies and Differences.
Manfredini, Roberto; Manfredini, Fabio; Fabbian, Fabio; Salmi, Raffaella; Gallerani, Massimo; Bossone, Eduardo; Deshmukh, Abhishek J
2016-10-01
Several pathophysiologic factors, not harmful if taken alone, are capable of triggering unfavorable events when presenting together within the same temporal window (chronorisk), and the occurrence of many cardiovascular events is not evenly distributed in time. Both acute myocardial infarction and takotsubo syndrome seem to exhibit a temporal preference in their onset, characterized by variations according to time of day, day of the week, and month of the year, although with both analogies and differences. Copyright © 2016 Elsevier Inc. All rights reserved.
Recent Developments in the UltraForm Finishing and UltraSurf Measuring of Axisymmetric IR Domes
2010-06-08
Approved for public release; distribution is unlimited. 13. SUPPLEMENTARY NOTES Presented at Mirror Technology Days, Boulder, Colorado, USA......deterministic fabrication solution for a wide range of newly developed windows , domes and mirrors . COMMERCIALIZATION UltraForm Finishing ( UFF
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ohsawa, R.; Sakon, I.; Onaka, T.
2010-08-01
We present the results of near-infrared (NIR) multi-epoch observations of the optical transient in the nearby galaxy NGC 300 (NGC 300-OT) at 398 and 582 days after the discovery with the Infrared Camera (IRC) on board AKARI. NIR spectra (2-5 {mu}m) of NGC 300-OT were obtained for the first time. They show no prominent emission nor absorption features, but are dominated by continuum thermal emission from the dust around NGC 300-OT. NIR images were taken in the 2.4, 3.2, and 4.1 {mu}m bands. The spectral energy distributions (SEDs) of NGC 300-OT indicate the dust temperature of 810 {+-} 14 Kmore » at 398 days and 670 {+-} 12 K at 582 days. We attribute the observed NIR emission to the thermal emission from dust grains formed in the ejecta of NGC 300-OT. The multi-epoch observations enable us to estimate the dust optical depth as {approx}>12 at 398 days and {approx}>6 at 582 days at 2.4 {mu}m by assuming an isothermal dust cloud. The observed NIR emission must be optically thick, unless the amount of dust grains increases with time. Little extinction at visible wavelengths reported in earlier observations suggests that the dust cloud around NGC 300-OT should be distributed inhomogeneously so as to not screen the radiation from the ejecta gas and the central star. The present results suggest the dust grains are not formed in a spherically symmetric geometry, but rather in a torus, a bipolar outflow, or clumpy cloudlets.« less
A Mathematical Modelling Approach to One-Day Cricket Batting Orders
Bukiet, Bruce; Ovens, Matthews
2006-01-01
While scoring strategies and player performance in cricket have been studied, there has been little published work about the influence of batting order with respect to One-Day cricket. We apply a mathematical modelling approach to compute efficiently the expected performance (runs distribution) of a cricket batting order in an innings. Among other applications, our method enables one to solve for the probability of one team beating another or to find the optimal batting order for a set of 11 players. The influence of defence and bowling ability can be taken into account in a straightforward manner. In this presentation, we outline how we develop our Markov Chain approach to studying the progress of runs for a batting order of non- identical players along the lines of work in baseball modelling by Bukiet et al., 1997. We describe the issues that arise in applying such methods to cricket, discuss ideas for addressing these difficulties and note limitations on modelling batting order for One-Day cricket. By performing our analysis on a selected subset of the possible batting orders, we apply the model to quantify the influence of batting order in a game of One Day cricket using available real-world data for current players. Key Points Batting order does effect the expected runs distribution in one-day cricket. One-day cricket has fewer data points than baseball, thus extreme values have greater effect on estimated probabilities. Dismissals rare and probabilities very small by comparison to baseball. Probability distribution for lower order batsmen is potentially skewed due to increased risk taking. Full enumeration of all possible line-ups is impractical using a single average computer. PMID:24357943
A mathematical modelling approach to one-day cricket batting orders.
Bukiet, Bruce; Ovens, Matthews
2006-01-01
While scoring strategies and player performance in cricket have been studied, there has been little published work about the influence of batting order with respect to One-Day cricket. We apply a mathematical modelling approach to compute efficiently the expected performance (runs distribution) of a cricket batting order in an innings. Among other applications, our method enables one to solve for the probability of one team beating another or to find the optimal batting order for a set of 11 players. The influence of defence and bowling ability can be taken into account in a straightforward manner. In this presentation, we outline how we develop our Markov Chain approach to studying the progress of runs for a batting order of non- identical players along the lines of work in baseball modelling by Bukiet et al., 1997. We describe the issues that arise in applying such methods to cricket, discuss ideas for addressing these difficulties and note limitations on modelling batting order for One-Day cricket. By performing our analysis on a selected subset of the possible batting orders, we apply the model to quantify the influence of batting order in a game of One Day cricket using available real-world data for current players. Key PointsBatting order does effect the expected runs distribution in one-day cricket.One-day cricket has fewer data points than baseball, thus extreme values have greater effect on estimated probabilities.Dismissals rare and probabilities very small by comparison to baseball.Probability distribution for lower order batsmen is potentially skewed due to increased risk taking.Full enumeration of all possible line-ups is impractical using a single average computer.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vitti, R.A.; Meyers, F.; Knight, L.C.
1989-11-01
Rectally administered suspensions of 5-aminosalicylic acid (5-ASA) are topically effective in treating left-sided ulcerative colitis. The extent to which the contents of these enemas are distributed to inflamed mucosal linings has not previously been determined. This study was undertaken to validate a technique for labeling 5-ASA with 99mTc and to quantitate the distribution of (99mTc)5-ASA in eight patients with left-sided ulcerative colitis. Eight patients underwent three colonic scintigraphic exams within five days, receiving a 60-ml radiolabeled 5-ASA enema into the unprepared rectum for each study, with sequential anterior abdominal images obtained for 4 hr. Activity within the rectum, sigmoid, descending,more » transverse, and ascending colon was quantitated. Over 50% of the labeled enema had advanced beyond the rectum in five of eight patients and in six of eight patients by 30 min and 60 min, respectively. The distribution of (99mTc)5-ASA was quantitatively reproducible when repeated in the same patient on different days, despite apparent visual differences. By 2 hr, the amount of the enema present within the rectum decreased significantly (P less than 0.05) compared to the initial distribution. The amount of enema present within the descending colon was increased significantly at 0.5 hr (P less than 0.05) and at 2 hr (P less than 0.01). There were no significant changes in the distribution from initial values for the sigmoid, transverse, or ascending colon at any time. In each of these cases the spread of the enema to or beyond the extent of disease was documented. In patients with left-sided ulcerative colitis, small volume (99mTc)5-ASA enemas reliably reach the area of inflammation.« less
Triviño, Maria; Thuiller, Wilfried; Cabeza, Mar; Hickler, Thomas; Araújo, Miguel B.
2011-01-01
Although climate is known to be one of the key factors determining animal species distributions amongst others, projections of global change impacts on their distributions often rely on bioclimatic envelope models. Vegetation structure and landscape configuration are also key determinants of distributions, but they are rarely considered in such assessments. We explore the consequences of using simulated vegetation structure and composition as well as its associated landscape configuration in models projecting global change effects on Iberian bird species distributions. Both present-day and future distributions were modelled for 168 bird species using two ensemble forecasting methods: Random Forests (RF) and Boosted Regression Trees (BRT). For each species, several models were created, differing in the predictor variables used (climate, vegetation, and landscape configuration). Discrimination ability of each model in the present-day was then tested with four commonly used evaluation methods (AUC, TSS, specificity and sensitivity). The different sets of predictor variables yielded similar spatial patterns for well-modelled species, but the future projections diverged for poorly-modelled species. Models using all predictor variables were not significantly better than models fitted with climate variables alone for ca. 50% of the cases. Moreover, models fitted with climate data were always better than models fitted with landscape configuration variables, and vegetation variables were found to correlate with bird species distributions in 26–40% of the cases with BRT, and in 1–18% of the cases with RF. We conclude that improvements from including vegetation and its landscape configuration variables in comparison with climate only variables might not always be as great as expected for future projections of Iberian bird species. PMID:22216263
Variable step random walks, self-similar distributions, and pricing of options (Invited Paper)
NASA Astrophysics Data System (ADS)
Gunaratne, Gemunu H.; McCauley, Joseph L.
2005-05-01
A new theory for pricing of options is presented. It is based on the assumption that successive movements depend on the value of the return. The solution to the Fokker-Planck equation is shown to be an asymmetric exponential distribution, similar to those observed in intra-day currency markets. The "volatility smile", used by traders to correct the Black-Scholes pricing is shown to be a heuristic mechanism to implement options pricing formulae derived from our theory.
A proof of the theorem regarding the distribution of lift over the span for minimum induced drag
NASA Technical Reports Server (NTRS)
Durand, W F
1931-01-01
The proof of the theorem that the elliptical distribution of lift over the span is that which will give rise to the minimum induced drag has been given in a variety of ways, generally speaking too difficult to be readily followed by the graduate of the average good technical school of the present day. In the form of proof this report makes an effort to bring the matter more readily within the grasp of this class of readers.
Quantum key distribution with passive decoy state selection
NASA Astrophysics Data System (ADS)
Mauerer, Wolfgang; Silberhorn, Christine
2007-05-01
We propose a quantum key distribution scheme which closely matches the performance of a perfect single photon source. It nearly attains the physical upper bound in terms of key generation rate and maximally achievable distance. Our scheme relies on a practical setup based on a parametric downconversion source and present day, nonideal photon-number detection. Arbitrary experimental imperfections which lead to bit errors are included. We select decoy states by classical postprocessing. This allows one to improve the effective signal statistics and achievable distance.
Planet Hunters: New Kepler Planet Candidates from Analysis of Quarter 2
NASA Astrophysics Data System (ADS)
Lintott, Chris J.; Schwamb, Megan E.; Barclay, Thomas; Sharzer, Charlie; Fischer, Debra A.; Brewer, John; Giguere, Matthew; Lynn, Stuart; Parrish, Michael; Batalha, Natalie; Bryson, Steve; Jenkins, Jon; Ragozzine, Darin; Rowe, Jason F.; Schwainski, Kevin; Gagliano, Robert; Gilardi, Joe; Jek, Kian J.; Pääkkönen, Jari-Pekka; Smits, Tjapko
2013-06-01
We present new planet candidates identified in NASA Kepler Quarter 2 public release data by volunteers engaged in the Planet Hunters citizen science project. The two candidates presented here survive checks for false positives, including examination of the pixel offset to constrain the possibility of a background eclipsing binary. The orbital periods of the planet candidates are 97.46 days (KIC 4552729) and 284.03 (KIC 10005758) days and the modeled planet radii are 5.3 and 3.8 R ⊕. The latter star has an additional known planet candidate with a radius of 5.05 R ⊕ and a period of 134.49 days, which was detected by the Kepler pipeline. The discovery of these candidates illustrates the value of massively distributed volunteer review of the Kepler database to recover candidates which were otherwise uncataloged. .
The rates and time-delay distribution of multiply imaged supernovae behind lensing clusters
NASA Astrophysics Data System (ADS)
Li, Xue; Hjorth, Jens; Richard, Johan
2012-11-01
Time delays of gravitationally lensed sources can be used to constrain the mass model of a deflector and determine cosmological parameters. We here present an analysis of the time-delay distribution of multiply imaged sources behind 17 strong lensing galaxy clusters with well-calibrated mass models. We find that for time delays less than 1000 days, at z = 3.0, their logarithmic probability distribution functions are well represented by P(log Δt) = 5.3 × 10-4Δttilde beta/M2502tilde beta, with tilde beta = 0.77, where M250 is the projected cluster mass inside 250 kpc (in 1014M⊙), and tilde beta is the power-law slope of the distribution. The resultant probability distribution function enables us to estimate the time-delay distribution in a lensing cluster of known mass. For a cluster with M250 = 2 × 1014M⊙, the fraction of time delays less than 1000 days is approximately 3%. Taking Abell 1689 as an example, its dark halo and brightest galaxies, with central velocity dispersions σ>=500kms-1, mainly produce large time delays, while galaxy-scale mass clumps are responsible for generating smaller time delays. We estimate the probability of observing multiple images of a supernova in the known images of Abell 1689. A two-component model of estimating the supernova rate is applied in this work. For a magnitude threshold of mAB = 26.5, the yearly rate of Type Ia (core-collapse) supernovae with time delays less than 1000 days is 0.004±0.002 (0.029±0.001). If the magnitude threshold is lowered to mAB ~ 27.0, the rate of core-collapse supernovae suitable for time delay observation is 0.044±0.015 per year.
Off-line tracking of series parameters in distribution systems using AMI data
DOE Office of Scientific and Technical Information (OSTI.GOV)
Williams, Tess L.; Sun, Yannan; Schneider, Kevin
2016-05-01
Electric distribution systems have historically lacked measurement points, and equipment is often operated to its failure point, resulting in customer outages. The widespread deployment of sensors at the distribution level is enabling observability. This paper presents an off-line parameter value tracking procedure that takes advantage of the increasing number of measurement devices being deployed at the distribution level to estimate changes in series impedance parameter values over time. The tracking of parameter values enables non-diurnal and non-seasonal change to be flagged for investigation. The presented method uses an unbalanced Distribution System State Estimation (DSSE) and a measurement residual-based parameter estimationmore » procedure. Measurement residuals from multiple measurement snapshots are combined in order to increase the effective local redundancy and improve the robustness of the calculations in the presence of measurement noise. Data from devices on the primary distribution system and from customer meters, via an AMI system, form the input data set. Results of simulations on the IEEE 13-Node Test Feeder are presented to illustrate the proposed approach applied to changes in series impedance parameters. A 5% change in series resistance elements can be detected in the presence of 2% measurement error when combining less than 1 day of measurement snapshots into a single estimate.« less
NASA Astrophysics Data System (ADS)
Gyenge, N.; Ballai, I.; Baranyi, T.
2016-07-01
The aim of the present investigation is to study the spatio-temporal distribution of precursor flares during the 24 h interval preceding M- and X-class major flares and the evolution of follower flares. Information on associated (precursor and follower) flares is provided by Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI). Flare list, while the major flares are observed by the Geostationary Operational Environmental Satellite (GOES) system satellites between 2002 and 2014. There are distinct evolutionary differences between the spatio-temporal distributions of associated flares in about one-day period depending on the type of the main flare. The spatial distribution was characterized by the normalized frequency distribution of the quantity δ (the distance between the major flare and its precursor flare normalized by the sunspot group diameter) in four 6 h time intervals before the major event. The precursors of X-class flares have a double-peaked spatial distribution for more than half a day prior to the major flare, but it changes to a lognormal-like distribution roughly 6 h prior to the event. The precursors of M-class flares show lognormal-like distribution in each 6 h subinterval. The most frequent sites of the precursors in the active region are within a distance of about 0.1 diameter of sunspot group from the site of the major flare in each case. Our investigation shows that the build-up of energy is more effective than the release of energy because of precursors.
Tissue-specific distribution of the androgen receptor (AR) in the porcine fetus.
Burek, Małgorzata; Duda, Małgorzata; Knapczyk, Katarzyna; Koziorowski, Marek; Słomczyńska, Maria
2007-01-01
The aim of this study was to investigate androgen receptor (AR) expression in developing porcine fetuses. The localization of AR was examined on embryos obtained at different days of gestation: days 18, 32, 50, 71, 90 post coitum (p.c.), and in the several tissues collected from the newborn piglets of both sexes. AR expression was first observed on day 32 p.c. in the mesonephron region. RT-PCR did not show AR mRNA on day18 p.c., but the message was present starting from day 32. In the male differentiating gonads and in the male genital ducts AR protein was present at 50, 71 and 90 days of gestation. AR protein was also detected in the cords of stromal cells within the medulla of the ovary and in stromal cells investing the oogonial nests. Pregranulosa cells on day 90 of gestation and on day 1 post partum (p.p.) immunolabelled positively for AR. In the kidney, a number of AR-positive tubules were visible while the mesenchyme in the kidney was AR-negative. Immunoreactive AR was detected predominantly in the nuclei of epithelial cells of the budding component at different stages of gestation of porcine lung. The presence of AR during gestation in non-gonadal tissues suggests a role of androgen in these tissues.
Modelling the climatic niche of turtles: a deep-time perspective
Schmidt, Daniela N.; Valdes, Paul J.; Holroyd, Patricia A.; Farnsworth, Alexander
2016-01-01
Ectotherms have close physiological ties with the thermal environment; consequently, the impact of future climate change on their biogeographic distributions is of major interest. Here, we use the modern and deep-time fossil record of testudines (turtles, tortoises, and terrapins) to provide the first test of climate on the niche limits of both extant and extinct (Late Cretaceous, Maastrichtian) taxa. Ecological niche models are used to assess niche overlap in model projections for key testudine ecotypes and families. An ordination framework is applied to quantify metrics of niche change (stability, expansion, and unfilling) between the Maastrichtian and present day. Results indicate that niche stability over evolutionary timescales varies between testudine clades. Groups that originated in the Early Cretaceous show climatic niche stability, whereas those diversifying towards the end of the Cretaceous display larger niche expansion towards the modern. Temperature is the dominant driver of modern and past distributions, whereas precipitation is important for freshwater turtle ranges. Our findings demonstrate that testudines were able to occupy warmer climates than present day in the geological record. However, the projected rate and magnitude of future environmental change, in concert with other conservation threats, presents challenges for acclimation or adaptation. PMID:27655766
Distributed practice. The more the merrier? A randomised bronchoscopy simulation study.
Bjerrum, Anne Sofie; Eika, Berit; Charles, Peder; Hilberg, Ole
2016-01-01
The distribution of practice affects the acquisition of skills. Distributed practice has shown to be more effective for skills acquisition than massed training. However, it remains unknown as to which is the most effective distributed practice schedule for learning bronchoscopy skills through simulation training. This study compares two distributed practice schedules: One-day distributed practice and weekly distributed practice. Twenty physicians in training were randomly assigned to one-day distributed or weekly distributed bronchoscopy simulation practice. Performance was assessed with a pre-test, a post-test after each practice session, and a 4-week retention test using previously validated simulator measures. Data were analysed with repeated measures ANOVA. No interaction was found between group and test (F(4,72) <1.68, p>0.16), except for the measure 'percent-segments-entered', and no main effect of group was found for any of the measures (F(1,72)< 0.87, p>0.36), which indicates that there was no difference between the learning curves of the one-day distributed practice schedule and the weekly distributed practice schedule. We found no difference in effectiveness of bronchoscopy skills acquisition between the one-day distributed practice and the weekly distributed practice. This finding suggests that the choice of bronchoscopy training practice may be guided by what best suits the clinical practice.
IS THE SUICIDE RATE A RANDOM WALK?
Yang, Bijou; Lester, David; Lyke, Jennifer; Olsen, Robert
2015-06-01
The yearly suicide rates for the period 1933-2010 and the daily suicide numbers for 1990 and 1991 were examined for whether the distribution of difference scores (from year to year and from day to day) fitted a normal distribution, a characteristic of stochastic processes that follow a random walk. If the suicide rate were a random walk, then any disturbance to the suicide rate would have a permanent effect and national suicide prevention efforts would likely fail. The distribution of difference scores from day to day (but not the difference scores from year to year) fitted a normal distribution and, therefore, were consistent with a random walk.
Report on the Workshop ''Metal Production and Distribution in a Hierarchical Universe''
NASA Astrophysics Data System (ADS)
Saviane, I.; Bonifacio, P.; Spite, M.; Monaco, L.
2014-06-01
The workshop aimed at taking a global view of the evolution of metal abundances from the Big Bang to the present day, considering both observations and simulations. Abundance studies in stars and galaxies, and the variety of interstellar and intergalactic media, were covered. A summary of the workshop topics in order of decreasing redshift is presented, with considerable attention given to abundance studies of the Milky Way.
NASA Astrophysics Data System (ADS)
Biffi, V.; Planelles, S.; Borgani, S.; Rasia, E.; Murante, G.; Fabjan, D.; Gaspari, M.
2018-05-01
The uniformity of the intracluster medium (ICM) enrichment level in the outskirts of nearby galaxy clusters suggests that chemical elements were deposited and widely spread into the intergalactic medium before the cluster formation. This observational evidence is supported by numerical findings from cosmological hydrodynamical simulations, as presented in Biffi et al., including the effect of thermal feedback from active galactic nuclei. Here, we further investigate this picture, by tracing back in time the spatial origin and metallicity evolution of the gas residing at z = 0 in the outskirts of simulated galaxy clusters. In these regions, we find a large distribution of iron abundances, including a component of highly enriched gas, already present at z = 2. At z > 1, the gas in the present-day outskirts was distributed over tens of virial radii from the main cluster and had been already enriched within high-redshift haloes. At z = 2, about 40 {per cent} of the most Fe-rich gas at z = 0 was not residing in any halo more massive than 10^{11} h^{-1} M_{⊙} in the region and yet its average iron abundance was already 0.4, w.r.t. the solar value by Anders & Grevesse. This confirms that the in situ enrichment of the ICM in the outskirts of present-day clusters does not play a significant role, and its uniform metal abundance is rather the consequence of the accretion of both low-metallicity and pre-enriched (at z > 2) gas, from the diffuse component and through merging substructures. These findings do not depend on the mass of the cluster nor on its core properties.
Roth, B; Dannhof, B; Bruns, V
1991-01-01
Several studies present a great deal of information about putative efferent neurotransmitters and their distribution in the adult and developing cochlea. Anatomical mapping of outer hair cell efferent fibres during ontogeny is still not available. Using quantitative electron microscopy in combination with immunocytochemistry, the distribution of ChAT-like immunoreactivity in the developing rat was investigated. Adult-like immunoreactivity in the whole cochlea is first observed in 30-day-old rats. We localized the adult-like immunoreactivity in all efferent fibres and synapses of the outer hair cells along the entire cochlear duct. An adult-like reaction in the whole cochlea could be observed on the 25th day after birth in two out of three cases. On the 20th postnatal day, no adult-like ChAT immunoreactivity was found, with the exception of one case where labelling was seen in the basal region only. The adult-like ChAT immunoreactivity on the 30th day, 2-3 weeks after the onset of hearing, is the latest maturation of all features of the organ of Corti so far investigated. Synaptogenesis of the outer hair cell efferents reaches an adult-like appearance already on the 16th day after birth.
Wisconsin | Solar Research | NREL
of Interconnection â¤20 kW Category 1 (10 days engineering review; 10 days distribution system study study; $250 application fee) >200 kW and â¤1 MW Category 3 (20 days engineering review; 20 days distribution system study; $500 application fee) >1 MW and â¤15 MW Category 4 (40 days engineering review
Modeling surface response of the Greenland Ice Sheet to interglacial climate
NASA Astrophysics Data System (ADS)
Rau, Dominik; Rogozhina, Irina
2013-04-01
We present a new parameterization of surface mass balance (SMB) of the Greenland Ice Sheet (GIS) under interglacial climate conditions validated against recent satellite observations on a regional scale. Based on detailed analysis of the modeled surface melting and refreezing rates, we conclude that the existing SMB parameterizations fail to capture either spatial pattern or amplitude of the observed surface response of the GIS. This is due to multiple simplifying assumptions adopted by the majority of modeling studies within the frame of the positive degree day method. Modeled spatial distribution of surface melting is found to be highly sensitive to a choice of daily temperature standard deviation (SD) and degree-day factors, which are generally assumed to have uniform distribution across the entire Greenland region. However, the use of uniform SD distribution and the range of commonly used SD values are absolutely unsupported by the ERA-40 and ERA-Interim climate data. In this region, SD distribution is highly inhomogeneous and characterized by low amplitudes during the summer months in the areas where most surface ice melting occurs. In addition, the use of identical degree day factors on both the eastern and western slopes of the GIS results in overestimation of surface runoff along the western coast of Greenland and significant underestimation along its eastern coast. Our approach is to make use of (i) spatially and seasonally variable SDs derived from ERA-40 and ERA-Interim time series, and (ii) spatially variable degree-day factors, measured across Greenland, Arctic Canada, Norway, Spitsbergen and Iceland. We demonstrate that the new approach is extremely efficient for modeling the evolution of the GIS during the observational period and the entire Holocene interglacial.
Tegumental ultrastructure of Echinoparyphium recurvatum according to developmental stages
Woo, Ho-Choon; Hong, Sung-Jong
2002-01-01
The present study was performed to observe tegumental ultrastructure of Echinoparyphium recurvatum according to developmental stages. Worms (1, 3, 5 and 15-day old) were recovered from chicks experimentally infected with metacercariae from Radix auricularia coreana. One-day old worms were elongated and ventrally concave, and covered with peg-like tegumental spines except the adjacent areas of the head crown and excretory pore. Type I sensory papillae were distributed on the lip of the oral sucker, and grouped ciliated papillae were around the oral sucker. Peg-like tegumental spines were densely distributed on the anterior surface of the ventral sucker level. The ventral sucker had an aspinous tegument and no sensory papillae. Tegumental spines on the posterior surface of the ventral sucker level were sparsely distributed and disappeared posteriorly. In 3 and 5-day old worms, the tegument around the oral sucker was aspinose and wrinkled concentrically. The ventral sucker had a wrinkled tegument and many bulbous papillae. Type I sensory papillae were distributed between the bulbous papillae. Tegumental spines were spade-shaped with a terminal tip. A total of 45 collar spines including 4 end group ones on both ventral corners was alternately arranged in 2 rows. The 15-day old worms were very stout and their tegumental spines were tongue-shaped without a terminal tip. From the above results, it is confirmed that the surface ultrastructure of E. recurvatum was generally similar to that of other echinostomatid flukes. However, some features, i.e., morphological change of tegumental spines and appearence of sensory papillae on the ventral sucker according to development, and number, shape and arrangement of collar spines, were characteristic, which may be of taxonomic and bioecological significance. PMID:12073731
Nii, Shota; Shinohara, Koichi; Matsushita, Hiroshi; Noguchi, Yasuyuki; Watanabe, Kazushi; Wakatsuki, Akihiko
2016-07-01
Hepatic effects of estrogen therapy on low-density lipoprotein (LDL) subfraction or oxidative stress have not been previously evaluated. The purpose of the present study was to investigate whether the differential hepatic effects of estrogen affect plasma distribution of small dense LDL and free radical production in postmenopausal women. In all, 45 postmenopausal women were given 0.625 mg/day of oral conjugated equine estrogen (CEE) (n=15), 1.0 mg/day of oral 17β estradiol (E2) (n=15), or 50 μg/day of transdermal 17βE2 (n=15) for 3 months. Subjects received either estrogen alone or with dydrogesterone at 5 mg/day. Plasma concentrations of sex hormone-binding globulin (SHBG), lipids, metallic ions, and derivatives of reactive oxygen metabolites (d-ROMs) were measured. CEE, but not oral 17βE2, increased the plasma concentrations of triglyceride, copper (Cu), and d-ROMs and the ratio of small dense LDL/total LDL cholesterol, a marker for plasma distribution of small dense LDL. Transdermal 17βE2 decreased d-ROMs concentrations but did not significantly change other parameters. Plasma concentrations of SHBG increased in the 3 groups. Estrogen-induced changes in triglyceride correlated positively either with changes in SHBG (R=0.52, P=0.0002) or the ratio of small dense LDL/total LDL cholesterol (R=0.65, P<0.0001). Changes in Cu also correlated positively either with changes in SHBG (R=0.85, P<0.0001) or d-ROMs (R=0.86, P<0.0001). The hepatic effects of different routes or types of estrogen therapy may be associated with plasma distribution of small dense LDL and free radical production in postmenopausal women.
Using self-organizing maps to develop ambient air quality classifications: a time series example
2014-01-01
Background Development of exposure metrics that capture features of the multipollutant environment are needed to investigate health effects of pollutant mixtures. This is a complex problem that requires development of new methodologies. Objective Present a self-organizing map (SOM) framework for creating ambient air quality classifications that group days with similar multipollutant profiles. Methods Eight years of day-level data from Atlanta, GA, for ten ambient air pollutants collected at a central monitor location were classified using SOM into a set of day types based on their day-level multipollutant profiles. We present strategies for using SOM to develop a multipollutant metric of air quality and compare results with more traditional techniques. Results Our analysis found that 16 types of days reasonably describe the day-level multipollutant combinations that appear most frequently in our data. Multipollutant day types ranged from conditions when all pollutants measured low to days exhibiting relatively high concentrations for either primary or secondary pollutants or both. The temporal nature of class assignments indicated substantial heterogeneity in day type frequency distributions (~1%-14%), relatively short-term durations (<2 day persistence), and long-term and seasonal trends. Meteorological summaries revealed strong day type weather dependencies and pollutant concentration summaries provided interesting scenarios for further investigation. Comparison with traditional methods found SOM produced similar classifications with added insight regarding between-class relationships. Conclusion We find SOM to be an attractive framework for developing ambient air quality classification because the approach eases interpretation of results by allowing users to visualize classifications on an organized map. The presented approach provides an appealing tool for developing multipollutant metrics of air quality that can be used to support multipollutant health studies. PMID:24990361
[Distributions of H3K27me3 and its modification enzymes in different tissues of mice].
Wang, Yuying; Wang, Xinli; Zhang, Ran; Zhang, Zhiyan; Wang, Yu; Yang, Bo; Wang, Guanjie; Zhang, Xin; Ma, Fuhao; Xu, Hongye; Wu, Xiaohui; Zhang, Feng; Li, Qing
2017-11-01
Objective To investigate the levels of trimethylated histone 3 at lysine residue 27 (H3K27me3) and its modification enzymes Zeste gene enhancer homolog 2 (EZH2), lysine-specific demethylase 6B (Kdm6B/JMJD3) and lysine-specific demethylase 6A (Kdm6A/UTX) in tissues and organs of 7-day and 2-month postnatal mice. Methods Immunohistochemistry was used to detect the expressions of H3K27me3 and its modification enzymes EZH2, JMJD3 and UTX in the brain, salivary glands, back fat, thymus, lung, heart, stomach, intestines, liver, testes, and skin of 7-day and 2-month mice. Real-time quantitative PCR was used to confirm the results. The relationships between H3K27me3 and its modification enzymes were analyzed statistically. Results Immunohistochemistry showed H3K27me3 persistently present in all examined tissues of 7-day and 2-month mice. EZH2 was persistently expressed in the brain, heart, liver, and skin of 7-day and 2-month mice, but only expressed in the salivary glands, adipose tissues, thymus, lung, intestines, and testes of 2-month mice. JMJD3 was expressed in the brain, salivary glands, adipose tissues, lung, heart, stomach, intestines, testes, skin of 7-day mice, but was not expressed in the lung, adipose tissues and stomach of 2-month mice. UTX was expressed in the brain, salivary glands, adipose tissues, lung, heart, testes, skin of 7-day mice, but only expressed in the testes of 2-month mice. Most mRNA of H3K27 modification enzymes were moderately or highly expressed as their immunohistochemical results were positive. Conclusion There was H3K27me3 persistently present in the all examined tissues at different stages. EZH2 was mostly expressed in the brain, salivary glands, adipose tissues, thymus, lung, heart, intestines, liver, testes and skin of 2-month-old mice. JMJD3 and UTX were mostly expressed in the brain, salivary glands, adipose tissues, lung, heart, skin and testes of 7-day-old mice. No significant association was found between the distribution of H3K27me3 and the expression of EZH2. There was also no obvious inverse distribution relationship between H3K27me3 and JMJD3 or UTX. Moreover, there was no negative relationship between the distribution of EZH2, JMJD3 and UTX. These results suggest that EZH2, JMJD3 and UTX may play important roles in many tissues of mice after birth. The levels of H3K27me3 and its modified enzymes may be controlled by multiple factors in vivo to fulfill complex physiological functions.
Lee, Dana N.; Papeş, Monica; Van Den Bussche, Ronald A.
2012-01-01
Success of the cattle industry in Latin America is impeded by the common vampire bat, Desmodus rotundus, through decreases in milk production and mass gain and increased risk of secondary infection and rabies. We used ecological niche modeling to predict the current potential distribution of D. rotundus and the future distribution of the species for the years 2030, 2050, and 2080 based on the A2, A1B, and B1 climate scenarios from the Intergovernmental Panel on Climate Change. We then combined the present day potential distribution with cattle density estimates to identify areas where cattle are at higher risk for the negative impacts due to D. rotundus. We evaluated our risk prediction by plotting 17 documented outbreaks of cattle rabies. Our results indicated highly suitable habitat for D. rotundus occurs throughout most of Mexico and Central America as well as portions of Venezuela, Guyana, the Brazilian highlands, western Ecuador, northern Argentina, and east of the Andes in Peru, Bolivia, and Paraguay. With future climate projections suitable habitat for D. rotundus is predicted in these same areas and additional areas in French Guyana, Suriname, Venezuela and Columbia; however D. rotundus are not likely to expand into the U.S. because of inadequate ‘temperature seasonality.’ Areas with large portions of cattle at risk include Mexico, Central America, Paraguay, and Brazil. Twelve of 17 documented cattle rabies outbreaks were represented in regions predicted at risk. Our present day and future predictions can help authorities focus rabies prevention efforts and inform cattle ranchers which areas are at an increased risk of cattle rabies because it has suitable habitat for D. rotundus. PMID:22900023
Lee, Dana N; Papeş, Monica; Van den Bussche, Ronald A
2012-01-01
Success of the cattle industry in Latin America is impeded by the common vampire bat, Desmodus rotundus, through decreases in milk production and mass gain and increased risk of secondary infection and rabies. We used ecological niche modeling to predict the current potential distribution of D. rotundus and the future distribution of the species for the years 2030, 2050, and 2080 based on the A2, A1B, and B1 climate scenarios from the Intergovernmental Panel on Climate Change. We then combined the present day potential distribution with cattle density estimates to identify areas where cattle are at higher risk for the negative impacts due to D. rotundus. We evaluated our risk prediction by plotting 17 documented outbreaks of cattle rabies. Our results indicated highly suitable habitat for D. rotundus occurs throughout most of Mexico and Central America as well as portions of Venezuela, Guyana, the Brazilian highlands, western Ecuador, northern Argentina, and east of the Andes in Peru, Bolivia, and Paraguay. With future climate projections suitable habitat for D. rotundus is predicted in these same areas and additional areas in French Guyana, Suriname, Venezuela and Columbia; however D. rotundus are not likely to expand into the U.S. because of inadequate 'temperature seasonality.' Areas with large portions of cattle at risk include Mexico, Central America, Paraguay, and Brazil. Twelve of 17 documented cattle rabies outbreaks were represented in regions predicted at risk. Our present day and future predictions can help authorities focus rabies prevention efforts and inform cattle ranchers which areas are at an increased risk of cattle rabies because it has suitable habitat for D. rotundus.
NASA Astrophysics Data System (ADS)
Chapman, S. C.; Stainforth, D. A.; Watkins, N. W.
2014-12-01
Estimates of how our climate is changing are needed locally in order to inform adaptation planning decisions. This requires quantifying the geographical patterns in changes at specific quantiles or thresholds in distributions of variables such as daily temperature or precipitation. We develop a method[1] for analysing local climatic timeseries to assess which quantiles of the local climatic distribution show the greatest and most robust changes, to specifically address the challenges presented by 'heavy tailed' distributed variables such as daily precipitation. We extract from the data quantities that characterize the changes in time of the likelihood of daily precipitation above a threshold and of the relative amount of precipitation in those extreme precipitation days. Our method is a simple mathematical deconstruction of how the difference between two observations from two different time periods can be assigned to the combination of natural statistical variability and/or the consequences of secular climate change. This deconstruction facilitates an assessment of how fast different quantiles of precipitation distributions are changing. This involves both determining which quantiles and geographical locations show the greatest change but also, those at which any change is highly uncertain. We demonstrate this approach using E-OBS gridded data[2] timeseries of local daily precipitation from specific locations across Europe over the last 60 years. We treat geographical location and precipitation as independent variables and thus obtain as outputs the pattern of change at a given threshold of precipitation and with geographical location. This is model- independent, thus providing data of direct value in model calibration and assessment. Our results identify regionally consistent patterns which, dependent on location, show systematic increase in precipitation on the wettest days, shifts in precipitation patterns to less moderate days and more heavy days, and drying across all days which is of potential value in adaptation planning. [1] S C Chapman, D A Stainforth, N W Watkins, 2013 Phil. Trans. R. Soc. A, 371 20120287; D. A. Stainforth, S. C. Chapman, N. W. Watkins, 2013 Environ. Res. Lett. 8, 034031 [2] Haylock et al. 2008 J. Geophys. Res (Atmospheres), 113, D20119
Noctilucent cloud studies with Envisat/SCIAMACHY: Observations of the 5-day wave
NASA Astrophysics Data System (ADS)
von Savigny, C.; Bovensmann, H.; Burrows, J. P.; Schwartz, M. J.; Wu, D. L.
SCIAMACHY Scanning Imaging Absorption spectroMeter for Atmospheric CartograpHY measures scattered solar radiation in limb viewing geometry from the troposphere up to the mesopause covering the spectral range from 220 nm to 2380 nm It is therefore well suited to study the geographical distribution of NLCs their temporal evolution and also allows the retrieval of NLC particle sizes This presentation will give an overview of the NLC results obtained so far from SCIAMACHY limb scatter measurements A special focus will be on the first identification of the westward propagating wavenumber-1 5-day wave in collocated satellite measurements of NLC characteristics - NLC occurence rate brightness and radii - and mesopause temperature The temperature measurements were made with the Microwave Limb Sounder MLS on Aura The 5-day wave was recently identified in SNOE NLC brightness measurements Merkel et al 2003 The 5-day wave signature has a severe impact on the geographical distribution of NLCs as well as their particle radii Long-term changes in global middle atmospheric wind patterns affecting the vertical propagation of planetary wave signatures may be an important driver for long-term variations in NLC occurrence rates and NLC brightness
Phylogeographic insights into cryptic glacial refugia.
Provan, Jim; Bennett, K D
2008-10-01
The glacial episodes of the Quaternary (2.6 million years ago-present) were a major factor in shaping the present-day distributions of extant flora and fauna, with expansions and contractions of the ice sheets rendering large areas uninhabitable for most species. Fossil records suggest that many species survived glacial maxima by retreating to refugia, usually at lower latitudes. Recently, phylogeographic studies have given support to the existence of previously unknown, or cryptic, refugia. Here we summarise many of these insights into the glacial histories of species in cryptic refugia gained through phylogeographic approaches. Understanding such refugia might be important as the Earth heads into another period of climate change, in terms of predicting the effects on species distribution and survival.
Time of Day and Day of Week Trends in EMS Demand.
Cantwell, Kate; Morgans, Amee; Smith, Karen; Livingston, Michael; Spelman, Tim; Dietze, Paul
2015-01-01
We examined temporal variations in overall Emergency Medical Services (EMS) demand, as well as medical and trauma cases separately. We analyzed cases according to time of day and day of week to determine whether population level demand demonstrates temporal patterns that will increase baseline knowledge for EMS planning. We conducted a secondary analysis of data from the Ambulance Victoria data warehouse covering the period 2008-2011. We included all cases of EMS attendance which resulted in 1,203,803 cases for review. Data elements comprised age, gender, date and time of call to the EMS emergency number along with the clinical condition of the patient. We employed Poisson regression to analyze case numbers and trigonometric regression to quantify distribution patterns. EMS demand exhibited a bimodal distribution with the highest peak at 10:00 and a second smaller peak at 19:00. The highest number of cases occurred on Fridays, and the lowest on Tuesdays and Wednesdays. However, the distribution of cases throughout the day differed by day of week. Distribution patterns on Fridays, Saturdays and Sundays differed significantly from the rest of the week (p < 0.001). When categorized into medical or trauma cases, medical cases were more frequent during working hours and involved patients of higher mean age (57 years vs. 49 years for trauma, p < 0.001). Trauma cases peaked on Friday and Saturday nights around midnight. Day of week EMS demand distribution patterns reveal differences that can be masked in aggregate data. Day of week EMS demand distribution patterns showed not only which days have differences in demand but the times of day at which the demand changes. Patterns differed by case type as well. These differences in distribution are important for EMS demand planning. Increased understanding of EMS demand patterns is imperative in a climate of ever-increasing demand and fiscal constraints. Further research is needed into the effect of age and case type on EMS demand.
The distribution of middle tropospheric carbon monoxide during early October 1984
NASA Technical Reports Server (NTRS)
Reichle, Henry G., Jr.; Connors, Vickie S.; Holland, J. Alvin; Sherrill, Robert T.; Wallio, H. Andrew; Casas, Joseph C.; Condon, Estelle P.
1990-01-01
The measurement of Air Pollution from Satellite experiment measured the distribution of middle-tropospheric CO from the Space Shuttle during October 1984. The data represent average mixing ratios between 57 deg N and 57 deg S. Approximately 75,000 individual CO measurements were obtained during the 9-day mission. The data are presented in maps that show the CO mixing ratios averaged over 5 x 5-deg areas for 6 days of the mission. Comparisons with concurrent direct measurements taken aboard aircraft show that the inferred concentrations are systematically low by 20-40 percent, depending upon which direct measurement calibration standard is used. The data show that there are very large CO sources resulting from biomass burning over South America and southern Africa. Measured mixing ratios were high over northeast Asia and were highly variable over Europe.
PLANET HUNTERS: NEW KEPLER PLANET CANDIDATES FROM ANALYSIS OF QUARTER 2
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lintott, Chris J.; Schwamb, Megan E.; Schwainski, Kevin, E-mail: cjl@astro.ox.ac.uk
2013-06-15
We present new planet candidates identified in NASA Kepler Quarter 2 public release data by volunteers engaged in the Planet Hunters citizen science project. The two candidates presented here survive checks for false positives, including examination of the pixel offset to constrain the possibility of a background eclipsing binary. The orbital periods of the planet candidates are 97.46 days (KIC 4552729) and 284.03 (KIC 10005758) days and the modeled planet radii are 5.3 and 3.8 R{sub Circled-Plus }. The latter star has an additional known planet candidate with a radius of 5.05 R{sub Circled-Plus} and a period of 134.49 days,more » which was detected by the Kepler pipeline. The discovery of these candidates illustrates the value of massively distributed volunteer review of the Kepler database to recover candidates which were otherwise uncataloged.« less
Rakoczy, P E; Lai, M C; Watson, M; Seydel, U; Constable, I
1996-01-01
In this article, we describe the preliminary results of the development of an animal model that will enable us to study the effect of photoreceptor-derived debris accumulation on the normal function of the retina in vivo. An antisense oligonucleotide (Cat 5), saline, and two control oligonucleotides were injected into the vitreous of 7-week-old RCS-rdy+ rats. The uptake, distribution, and persistence of the antisense oligonucleotide in the retina was demonstrated by fluorescent confocal microscopy, and the stability of the oligonucleotide was shown by GeneScan analysis using a fluorescein-labeled derivative of Cat 5 (Cat 5F). The accumulation of photoreceptor-derived debris was monitored by the number of undigested phagosomes in the RPE layer by light microscopy. Following intravitreal injection of Cat 5F, penetration of the oligonucleotide was observed in the ganglion cell layer in 2 hours and in the photoreceptor and pigment epithelial layers 3 days later. However, at 7, 28, and 56 days postinjection, only the RPE layer had significant amounts of Cat 5F present. Using GeneScan analysis, it was demonstrated that the fluorescein-labeled oligonucleotide present in the RPE layer was not degraded and it retained its original 19-mer length. There was no statistically significant difference in the number of phagosomes found in the RPE layer of control uninjected, saline-injected, and two sense and two antisense oligonucleotides-injected animals at 7 and 28 days postinjection. In contrast, the number of phagosomes was significantly higher (p < 0.001) in the RPE layer of Cat 5 antisense oligonucleotide-injected animals at 7 and 28 days postinjection. This difference, however, disappeared by 56 days postinjection. The inner nuclear layers of the retina of control and experimental animals were not affected by the injections.
Fundamental studies in geodynamics
NASA Technical Reports Server (NTRS)
Anderson, D. L.
1980-01-01
Progress in modeling instantaneous plate kinematics is reviewed, with emphasis on recently developed models of present day plate motions derived by the systematic inversion of globally distributed data sets. Rivera plate motions, the Caribbean South American boundary, Indian plate deformation, Pacific-North America, seismicity and subduction processes, and the study of slow earthquakes and free oscillations are discussed.
Using Social Media to Measure Language Use
ERIC Educational Resources Information Center
Zhuravleva, Anastasia; de Bot, Kees; Hilton, Nanna Haug
2016-01-01
Investigations of language use in multilingual regions are traditionally done through the usage of retrospective questionnaires, either distributed on paper, or digitally. The aim of the present study was to test a new method of measuring language choice and use: by using social media to contact individuals several times a day and ask them what…
High Speed Computing, LANs, and WAMs
NASA Technical Reports Server (NTRS)
Bergman, Larry A.; Monacos, Steve
1994-01-01
Optical fiber networks may one day offer potential capacities exceeding 10 terabits/sec. This paper describes present gigabit network techniques for distributed computing as illustrated by the CASA gigabit testbed, and then explores future all-optic network architectures that offer increased capacity, more optimized level of service for a given application, high fault tolerance, and dynamic reconfigurability.
Distributed practice. The more the merrier? A randomised bronchoscopy simulation study
Bjerrum, Anne Sofie; Eika, Berit; Charles, Peder; Hilberg, Ole
2016-01-01
Introduction The distribution of practice affects the acquisition of skills. Distributed practice has shown to be more effective for skills acquisition than massed training. However, it remains unknown as to which is the most effective distributed practice schedule for learning bronchoscopy skills through simulation training. This study compares two distributed practice schedules: One-day distributed practice and weekly distributed practice. Method Twenty physicians in training were randomly assigned to one-day distributed or weekly distributed bronchoscopy simulation practice. Performance was assessed with a pre-test, a post-test after each practice session, and a 4-week retention test using previously validated simulator measures. Data were analysed with repeated measures ANOVA. Results No interaction was found between group and test (F(4,72) <1.68, p>0.16), except for the measure ‘percent-segments-entered’, and no main effect of group was found for any of the measures (F(1,72)< 0.87, p>0.36), which indicates that there was no difference between the learning curves of the one-day distributed practice schedule and the weekly distributed practice schedule. Discussion We found no difference in effectiveness of bronchoscopy skills acquisition between the one-day distributed practice and the weekly distributed practice. This finding suggests that the choice of bronchoscopy training practice may be guided by what best suits the clinical practice. PMID:27172423
Distributed practice. The more the merrier? A randomised bronchoscopy simulation study.
Bjerrum, Anne Sofie; Eika, Berit; Charles, Peder; Hilberg, Ole
2016-01-01
Introduction The distribution of practice affects the acquisition of skills. Distributed practice has shown to be more effective for skills acquisition than massed training. However, it remains unknown as to which is the most effective distributed practice schedule for learning bronchoscopy skills through simulation training. This study compares two distributed practice schedules: One-day distributed practice and weekly distributed practice. Method Twenty physicians in training were randomly assigned to one-day distributed or weekly distributed bronchoscopy simulation practice. Performance was assessed with a pre-test, a post-test after each practice session, and a 4-week retention test using previously validated simulator measures. Data were analysed with repeated measures ANOVA. Results No interaction was found between group and test (F(4,72) <1.68, p>0.16), except for the measure 'percent-segments-entered', and no main effect of group was found for any of the measures (F(1,72)< 0.87, p>0.36), which indicates that there was no difference between the learning curves of the one-day distributed practice schedule and the weekly distributed practice schedule. Discussion We found no difference in effectiveness of bronchoscopy skills acquisition between the one-day distributed practice and the weekly distributed practice. This finding suggests that the choice of bronchoscopy training practice may be guided by what best suits the clinical practice.
Study of the Cooldown and Warmup for the Eight Sectors of the Large Hadron Collider
NASA Astrophysics Data System (ADS)
Liu, L.; Riddone, G.; Tavian, L.
2004-06-01
The LHC cryogenic system is based on a five-point feed scheme with eight refrigerators serving the eight sectors of the LHC machine. The paper presents the simplified flow scheme of the eight sectors and the mathematical methods including the program flowchart and the boundary conditions to simulate the cooldown and warmup of these sectors. The methods take into account the effect of the pressure drop across the valves as well as the pressure evolution in the different headers of the cryogenic distribution line. The simulated pressure and temperature profiles of headers of the LHC sector during the cooldown and warmup are given and the temperature evolutions of entire processes of cooldown and warmup are presented. As a conclusion, the functions of the input temperature for the normal and fast cooldown and warmup, the cooldown and warmup time of each sector and the distributions of mass flow rates in each sector are summarized. The results indicate that it is possible to cool down any of the LHC sector within 12.7 days in normal operation and 6.8 days in case of fast operation.
Remoteness from sources of persistent organic pollutants in the multi-media global environment.
Göktaş, Recep Kaya; MacLeod, Matthew
2016-10-01
Quantifying the remoteness from sources of persistent organic pollutants (POPs) can inform the design of monitoring studies and the interpretation of measurement data. Previous work on quantifying remoteness has not explicitly considered partitioning between the gas phase and aerosols, and between the atmosphere and the Earth's surface. The objective of this study is to present a metric of remoteness for POPs transported through the atmosphere calculated with a global multimedia fate model, BETR-Research. We calculated the remoteness of regions covering the entire globe from emission sources distributed according to light emissions, and taking into account the multimedia partitioning properties of chemicals and using averaged global climate data. Remoteness for hypothetical chemicals with distinct partitioning properties (volatile, semi-volatile, hydrophilic, low-volatility) and having two different half-lives in air (60-day and 2-day) are presented. Differences in remoteness distribution among the hypothetical chemicals are most pronounced in scenarios assuming 60-day half-life in air. In scenarios with a 2-day half-life in air, degradation dominates over wet and dry deposition processes as a pathway for atmospheric removal of all chemicals except the low-volatility chemical. The remoteness distribution of the low-volatility chemical is strongly dependent on assumptions about degradability on atmospheric aerosols. Calculations that considered seasonal variability in temperature, hydroxyl radical concentrations in the atmosphere and global atmospheric and oceanic circulation patterns indicate that variability in hydroxyl radical concentrations largely determines the seasonal variability of remoteness. Concentrations of polybrominated diphenyl ethers (PBDEs) measured in tree bark from around the world are more highly correlated with remoteness calculated using our methods than with proximity to human population, and we see considerable potential to apply remoteness calculations for interpretation of monitoring data collected under programs such as the Stockholm Convention Global Monitoring Plan. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.
NASA Astrophysics Data System (ADS)
Landin, N. R.; Mendes, L. T. S.; Vaz, L. P. R.; Alencar, S. H. P.
2016-02-01
Context. Rotational evolution in young stars is described by pre-main sequence evolutionary tracks including non-gray boundary conditions, rotation, conservation of angular momentum, and simulations of disk-locking. Aims: By assuming that disk-locking is the regulation mechanism for the stellar angular velocity during the early stages of pre-main sequence evolution, we use our rotating models and observational data to constrain disk lifetimes (Tdisk) of a representative sample of low-mass stars in two young clusters, the Orion Nebula cluster (ONC) and NGC 2264, and to better understand their rotational evolution. Methods: The period distributions of the ONC and NGC 2264 are known to be bimodal and to depend on the stellar mass. To follow the rotational evolution of these two clusters' stars, we generated sets of evolutionary tracks from a fully convective configuration with low central temperatures (before D- and Li-burning). We assumed that the evolution of fast rotators can be represented by models considering conservation of angular momentum during all stages and of moderate rotators by models considering conservation of angular velocity during the first stages of evolution. With these models we estimate a mass and an age for all stars. Results: The resulting mass distribution for the bulk of the cluster population is in the ranges of 0.2-0.4 M⊙ and 0.1-0.6 M⊙ for the ONC and NGC 2264, respectively. For the ONC, we assume that the secondary peak in the period distribution is due to high-mass objects still locked in their disks, with a locking period (Plock) of ~8 days. For NGC 2264 we make two hypotheses: (1) the stars in the secondary peak are still locked with Plock = 5 days, and (2) NGC 2264 is in a later stage in the rotational evolution. Hypothesis 2 implies in a disk-locking scenario with Plock = 8 days, a disk lifetime of 1 Myr and, after that, constant angular momentum evolution. We then simulated the period distribution of NGC 2264 when the mean age of the cluster was 1 Myr. Dichotomy and bimodality appear in the simulated distribution, presenting one peak at 2 days and another one at 5-7 days, indicating that the assumption of Plock = 8 days is plausible. Our hypotheses are compared with observational disk diagnoses available in the literature for the ONC and NGC 2264, such as near-infrared excess, Hα emission, and spectral energy distribution slope in the mid-infrared. Conclusions: Disk-locking models with Plock = 8 days and 0.2 Myr ≤ Tdisk ≤ 3 Myr are consistent with observed periods of moderate rotators of the ONC. For NGC 2264, the more promising explanation for the observed period distribution is an evolution with disk-locking (with Plock near 8 days) during the first 1 Myr, approximately, but after this, the evolution continued with constant angular momentum. Full Table 1 is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/586/A96
Curra, Marina; Martins, Marco Antonio T; Lauxen, Isabel S; Pellicioli, Ana Carolina A; Sant'Ana Filho, Manoel; Pavesi, Vanessa Christina S; Carrard, Vinicius C; Martins, Manoela D
2013-02-01
The aim of the present study was to evaluate the effect of topical chamomile and corticosteroid treatment on the profile of tissue cytokines (IL-1β and TNF-α) in 5-fluorouracil-induced oral mucositis in hamsters. Thirty-six hamsters were randomly separated into three groups (12 animals each): Group I--without treatment (control); Group II-treatment with chamomile (Ad-Muc(®)); and Group III--treatment with corticosteroid (betamethasone elixir- Celestone(®)). The animals received an intraperitoneal injection of 5--fluorouracil on Days 0 and 2. On Days 3 and 4, the buccal mucosa was scratched and therapy was initiated on Day 5. Three animals from each group were killed on Days 0, 5, 10, and 14 and the buccal mucosa was removed. The streptavidin-biotin complex method was used to delineate the in situ distribution, localization, and semiquantitative analysis of IL-1β and TNF-α. Data from the semiquantitative analysis of immunohistochemical staining were comparatively analyzed using the Kruskal-Wallis test, followed by Dunn's multiple comparisons test. The distribution and localization of IL-1β and TNF-α immunolabeling were similar. These proteins exhibited a diffuse pattern distributed throughout the connective tissue. The epithelium and adipose tissue were negative for both proteins. The semiquantitative analysis revealed that immunolabeling of IL-1β and TNF-α increased in all groups with the development of mucositis. On Day 10 (period of peak mucositis), the group treated with chamomile had lower scores for both pro-inflammatory cytokines. Treatment with topical chamomile reduced the tissue levels of IL-1β and TNF-α, thereby demonstrating anti-inflammatory action in oral mucositis in hamsters.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, Chao ..; Singh, Vijay P.; Mishra, Ashok K.
2013-02-06
This paper presents an improved brivariate mixed distribution, which is capable of modeling the dependence of daily rainfall from two distinct sources (e.g., rainfall from two stations, two consecutive days, or two instruments such as satellite and rain gauge). The distribution couples an existing framework for building a bivariate mixed distribution, the theory of copulae and a hybrid marginal distribution. Contributions of the improved distribution are twofold. One is the appropriate selection of the bivariate dependence structure from a wider admissible choice (10 candidate copula families). The other is the introduction of a marginal distribution capable of better representing lowmore » to moderate values as well as extremes of daily rainfall. Among several applications of the improved distribution, particularly presented here is its utility for single-site daily rainfall simulation. Rather than simulating rainfall occurrences and amounts separately, the developed generator unifies the two processes by generalizing daily rainfall as a Markov process with autocorrelation described by the improved bivariate mixed distribution. The generator is first tested on a sample station in Texas. Results reveal that the simulated and observed sequences are in good agreement with respect to essential characteristics. Then, extensive simulation experiments are carried out to compare the developed generator with three other alternative models: the conventional two-state Markov chain generator, the transition probability matrix model and the semi-parametric Markov chain model with kernel density estimation for rainfall amounts. Analyses establish that overall the developed generator is capable of reproducing characteristics of historical extreme rainfall events and is apt at extrapolating rare values beyond the upper range of available observed data. Moreover, it automatically captures the persistence of rainfall amounts on consecutive wet days in a relatively natural and easy way. Another interesting observation is that the recognized ‘overdispersion’ problem in daily rainfall simulation ascribes more to the loss of rainfall extremes than the under-representation of first-order persistence. The developed generator appears to be a sound option for daily rainfall simulation, especially in particular hydrologic planning situations when rare rainfall events are of great importance.« less
Almoosawi, S; Vingeliene, S; Karagounis, L G; Pot, G K
2016-11-01
The importance of the circadian rhythm in regulating human food intake behaviour and metabolism has long been recognised. However, little is known as to how energy intake is distributed over the day in existing populations, and its potential association with obesity. The present review describes global trends in time-of-day of energy intake in the general population based on data from cross-sectional surveys and longitudinal cohorts. Evidence of the association between time-of-day of energy intake and obesity is also summarised. Overall, there were a limited number of cross-sectional surveys and longitudinal cohorts that provided data on time-of-day of energy intake. In the identified studies, a wide variation in time-of-day of energy intake was observed, with patterns of energy distribution varying greatly by country and geographical area. In relation to obesity, eight cross-sectional surveys and two longitudinal cohorts were identified. The association between time-of-day of energy intake and obesity varied widely, with several studies reporting a positive link between evening energy intake and obesity. In conclusion, the current review summarises global trends in time-of-day of energy intake. The large variations across countries and global regions could have important implications to health, emphasising the need to understand the socio-environmental factors guiding such differences in eating patterns. Evidence of the association between time-of-day of energy intake and BMI also varied. Further larger scale collaborations between various countries and regions are needed to sum data from existing surveys and cohorts, and guide our understanding of the role of chrono-nutrition in health.
Distribution of emamectin benzoate in Atlantic salmon (Salmo salar L.).
Sevatdal, S; Magnusson, A; Ingebrigtsen, K; Haldorsen, R; Horsberg, T E
2005-02-01
The aims of this study were to investigate the content of emamectin in blood, mucus and muscle following field administration of the recommended dose, and correlation with sea lice infection on the same fish (elimination study). The tissue distribution of tritiated emamectin benzoate after a single oral dose in Atlantic salmon was also investigated by means of whole-body autoradiography and scintillation counting (distribution study). In the elimination study, concentrations of emamectin benzoate reached maximum levels of 128, 105 and 68 ng/g (p.p.b.) for blood, mucus and muscle respectively, on day 7, the last day of administration. From day 7, the concentration in the blood declined until concentration was less than the limit of detection on day 77. The concentration was higher in mucus compared with plasma (P < 0.05) except on days 7 and 21. The concentration of emamectin benzoate decreased gradually from the end of treatment (day 7) to day 70 with half-lives of 9.2, 10.0 and 11.3 days in muscle, plasma and mucus respectively. The distribution study demonstrated a high quantity of radioactivity in mucous membranes (gastrointestinal tract, gills) throughout the observation period (56 days). Activity was high in the epiphysis, hypophysis and olfactory rosette throughout the study. The highest activity was observed in the bile, indicating this to be an important route for excretion. The distribution study confirmed the results from the elimination study with respect to concentrations in blood, skin mucous and muscle.
Thunderstorm distribution and frequency in Saudi Arabia
NASA Astrophysics Data System (ADS)
Shwehdi, M. H.
2005-09-01
A new average annual thunder day map for Saudi Arabia is presented. Based on this map, the distribution of thunderstorms over Saudi Arabia is analysed in terms of the factors related to the lightning performance of transmission lines such as thunderstorm days per year (Td/yr). Lightning activity continues for the present to be represented by thunderstorm frequency, which is routinely recorded at meteorological observation sites. Thunderstorm occurrence at a particular location is usually expressed as the number of days in a calendar year when thunder was heard, averaged over several years. This paper examines thunderstorm days in different areas of Saudi Arabia and specifically those areas where lightning strikes are more frequent; for this purpose, the software ArcGIS is used to produce contour maps which demonstrate areas of concern in Saudi Arabia in the period 1985-2003. Establishing the annual and seasonal Td/yr for Saudi Arabia enables transmission and distribution line engineers to calculate and better design a lightning protection system. Maps of thunder days/year (Td/yr) were constructed on the basis of the database records available on lightning incidence in Saudi Arabia at the Presidency of Meteorology and Environment (PME) (http://www.pme.gov.sa/). Annual thunderstorms are most frequent over the southwestern parts of the country, and generally decrease towards the west and east. Due to its low latitude and less temporal change, the west coast of the Red Sea recorded the lowest Td/yr. A secondary maximum Td/yr is apparent in the southeast to central part of the country. Thunderstorm frequency does not, in general, appear to vary in any consistent way with rainfall. There appears to be no evidence of any widespread temporal trend in thunderstorm frequency. The southern region in general, and especially the cities of Abha, Taif and Al-Baha, has shown greater numbers of thunderstorm days all year round. Similarly, this variation did show higher frequency throughout the year. The development of lightning incidence and the counting of Td/yr, as well as the establishment of annual and seasonal lightning maps of Saudi Arabia, are initiating a new era of producing and archiving thunderstorm maps and data records which serve the PME, the utilities, industry and the public.
Spectroscopy of geoneutrinos from 2056 days of Borexino data
NASA Astrophysics Data System (ADS)
Agostini, M.; Appel, S.; Bellini, G.; Benziger, J.; Bick, D.; Bonfini, G.; Bravo, D.; Caccianiga, B.; Calaprice, F.; Caminata, A.; Cavalcante, P.; Chepurnov, A.; Choi, K.; D'Angelo, D.; Davini, S.; Derbin, A.; Di Noto, L.; Drachnev, I.; Empl, A.; Etenko, A.; Fiorentini, G.; Fomenko, K.; Franco, D.; Gabriele, F.; Galbiati, C.; Ghiano, C.; Giammarchi, M.; Goeger-Neff, M.; Goretti, A.; Gromov, M.; Hagner, C.; Houdy, T.; Hungerford, E.; Ianni, Aldo; Ianni, Andrea; Jedrzejczak, K.; Kaiser, M.; Kobychev, V.; Korablev, D.; Korga, G.; Kryn, D.; Laubenstein, M.; Lehnert, B.; Litvinovich, E.; Lombardi, F.; Lombardi, P.; Ludhova, L.; Lukyanchenko, G.; Machulin, I.; Manecki, S.; Maneschg, W.; Mantovani, F.; Marcocci, S.; Meroni, E.; Meyer, M.; Miramonti, L.; Misiaszek, M.; Montuschi, M.; Mosteiro, P.; Muratova, V.; Neumair, B.; Oberauer, L.; Obolensky, M.; Ortica, F.; Otis, K.; Pagani, L.; Pallavicini, M.; Papp, L.; Perasso, L.; Pocar, A.; Ranucci, G.; Razeto, A.; Re, A.; Ricci, B.; Romani, A.; Roncin, R.; Rossi, N.; Schönert, S.; Semenov, D.; Simgen, H.; Skorokhvatov, M.; Smirnov, O.; Sotnikov, A.; Sukhotin, S.; Suvorov, Y.; Tartaglia, R.; Testera, G.; Thurn, J.; Toropova, M.; Unzhakov, E.; Vogelaar, R. B.; von Feilitzsch, F.; Wang, H.; Weinz, S.; Winter, J.; Wojcik, M.; Wurm, M.; Yokley, Z.; Zaimidoroga, O.; Zavatarelli, S.; Zuber, K.; Zuzel, G.; Borexino Collaboration
2015-08-01
We report an improved geoneutrino measurement with Borexino from 2056 days of data taking. The present exposure is (5.5 ±0.3 )×1031 proton ×yr . Assuming a chondritic Th/U mass ratio of 3.9, we obtain 23.7-5.7+6.5(stat)-0.6+0.9(sys) geoneutrino events. The null observation of geoneutrinos with Borexino alone has a probability of 3.6 ×10-9 (5.9 σ ). A geoneutrino signal from the mantle is obtained at 98% C.L. The radiogenic heat production for U and Th from the present best-fit result is restricted to the range 23-36 TW, taking into account the uncertainty on the distribution of heat producing elements inside the Earth.
NASA Astrophysics Data System (ADS)
Kamal Chowdhury, AFM; Lockart, Natalie; Willgoose, Garry; Kuczera, George; Kiem, Anthony; Parana Manage, Nadeeka
2016-04-01
Stochastic simulation of rainfall is often required in the simulation of streamflow and reservoir levels for water security assessment. As reservoir water levels generally vary on monthly to multi-year timescales, it is important that these rainfall series accurately simulate the multi-year variability. However, the underestimation of multi-year variability is a well-known issue in daily rainfall simulation. Focusing on this issue, we developed a hierarchical Markov Chain (MC) model in a traditional two-part MC-Gamma Distribution modelling structure, but with a new parameterization technique. We used two parameters of first-order MC process (transition probabilities of wet-to-wet and dry-to-dry days) to simulate the wet and dry days, and two parameters of Gamma distribution (mean and standard deviation of wet day rainfall) to simulate wet day rainfall depths. We found that use of deterministic Gamma parameter values results in underestimation of multi-year variability of rainfall depths. Therefore, we calculated the Gamma parameters for each month of each year from the observed data. Then, for each month, we fitted a multi-variate normal distribution to the calculated Gamma parameter values. In the model, we stochastically sampled these two Gamma parameters from the multi-variate normal distribution for each month of each year and used them to generate rainfall depth in wet days using the Gamma distribution. In another study, Mehrotra and Sharma (2007) proposed a semi-parametric Markov model. They also used a first-order MC process for rainfall occurrence simulation. But, the MC parameters were modified by using an additional factor to incorporate the multi-year variability. Generally, the additional factor is analytically derived from the rainfall over a pre-specified past periods (e.g. last 30, 180, or 360 days). They used a non-parametric kernel density process to simulate the wet day rainfall depths. In this study, we have compared the performance of our hierarchical MC model with the semi-parametric model in preserving rainfall variability in daily, monthly, and multi-year scales. To calibrate the parameters of both models and assess their ability to preserve observed statistics, we have used ground based data from 15 raingauge stations around Australia, which consist a wide range of climate zones including coastal, monsoonal, and arid climate characteristics. In preliminary results, both models show comparative performances in preserving the multi-year variability of rainfall depth and occurrence. However, the semi-parametric model shows a tendency of overestimating the mean rainfall depth, while our model shows a tendency of overestimating the number of wet days. We will discuss further the relative merits of the both models for hydrology simulation in the presentation.
Present and future free-space quantum key distribution
NASA Astrophysics Data System (ADS)
Nordholt, Jane E.; Hughes, Richard J.; Morgan, George L.; Peterson, C. Glen; Wipf, Christopher C.
2002-04-01
Free-space quantum key distribution (QKD), more popularly know as quantum cryptography, uses single-photon free-space optical communications to distribute the secret keys required for secure communications. At Los Alamos National Laboratory we have demonstrated a fully automated system that is capable of operations at any time of day over a horizontal range of several kilometers. This has proven the technology is capable of operation from a spacecraft to the ground, opening up the possibility of QKD between any group of users anywhere on Earth. This system, the prototyping of a new system for use on a spacecraft, and the techniques required for world-wide quantum key distribution will be described. The operational parameters and performance of a system designed to operate between low earth orbit (LEO) and the ground will also be discussed.
Mid-Pliocene planktic foraminifer assemblage of the North Atlantic Ocean
Dowsett, H.J.; Robinson, M.M.
2007-01-01
The US Geological Survey Pliocene Research, Interpretation and Synoptic Mapping (PRISM) North Atlantic faunal data set provides a unique, temporally constrained perspective to document and evaluate the quantitative geographic distribution of key mid-Pliocene taxa. Planktic foraminifer census data from within the PRISM time slab (3.29 to 2.97 Ma) at thirteen sites in the North Atlantic Ocean have been analyzed. We have compiled Scanning Electron Micrographs for an atlas of mid-Pliocene assemblages from the North Atlantic with descriptions of each taxon to document the taxonomic concepts that accompany the PRISM data. In mid-Pliocene assemblages, the geographic distributions of extant taxa are similar to their present day distributions, although some are extended to the north. We use the distribution of extinct taxa to assess previous assumptions regarding environmental preferences.
Valente, Eriton Egidio Lisboa; Paulino, Mario Fonseca; Detmann, Edenio; Valadares Filho, Sebastião de Campos; Barros, Livia Vieira; Cabral, Carla Heloisa Avelino; Silva, Aline Gomes; Duarte, Marcio de Souza
2012-10-01
The performance of female calves in creep feeding under different strategies of supplementation and milk production, intake, and digestibility of grazing Nellore and crossbred cows (Nellore × Holstein) during the dry-rainy transition season were assessed. Forty-four female beef suckling calves, with initial age between 90 and 150 days and average initial body weight of 117.7 ± 4.3 kg, and their respective dams (24 Nellore and 20 crossbred) with average initial body weight of 417.5 ± 8.3 kg, were used. The experimental treatments consisted of: control group--mineral mixture only; strategy 1--supplementation from 112 days prior to weaning (0.375 kg/animal/day); strategy 2--supplementation from 112 days prior to weaning, in increasing amounts of 0.15, 0.30, 0.45, and 0.60 kg/animal/day through the four experimental periods, respectively; and strategy 3--supplementation from 56 days prior to weaning (0.750 kg/animal/day). Calves from strategy 1 had greater (P < 0.05) average daily gain (0.672 kg/day) than control animals (0.582 kg/day) and greater (P < 0.05) efficiency of supplement use than the other groups. Crossbred cows produced more milk than Nellore cows (P < 0.05). Crossbred cows presented greater (P < 0.05) dry matter intake (DMI) than Nellore cows. However, no differences were found (P > 0.05) for nutrient digestibility among genetic types. It can be concluded that strategies of supplementation that present an equitable distribution of supplement provides greater weight gain in suckling female beef calves. Crossbred cows produce more milk and present greater DMI than Nellore cows. There are no differences in the nutrient digestibility between Nellore and Nellore × Holstein crossbred cows.
Felder, Seth I; Larson, Brent; Balzer, Bonnie; Wachsman, Ashley; Haker, Katherine; Fleshner, Phillip; Annamalai, Alagappan; Margulies, Daniel R
2014-10-01
A Total abdominal colectomy (TAC) is recommended for fulminant Clostridium difficile colitis (FCDC) because intraoperative assessment of diseased segments is inaccurate. To determine whether computerized tomography (CT) provides an accurate assessment of disease, we examined the concordance between CT and histopathologic colitis distribution in patients undergoing TAC for FCDC. The ileocolon was divided into seven distinct segments. Of 20 patients meeting criteria, the median interval between preoperative CT and TAC was 1.5 days (range, 0 to 23 days), and mortality was 65 per cent. The CT distribution of colitis was pancolitis in 12 patients and segmental in eight. Nine of the 12 patients with CT pancolitis had histologic pancolitis (75% concordance). Four of the eight patients with CT-diagnosed segmental disease had histologic segmental disease (50% concordance). For patients with FCDC, the distribution of colitis on CT agrees with the histopathologic extent of disease in the majority of patients. However, discordance between CT and histologic extent of disease was present in 25 to 50 per cent of patients. Therefore, the recommendation for TAC rather than segmental resection for FCDC remains justified.
NASA Astrophysics Data System (ADS)
Bin, Che; Ruoying, Yu; Dongsheng, Dang; Xiangyan, Wang
2017-05-01
Distributed Generation (DG) integrating to the network would cause the harmonic pollution which would cause damages on electrical devices and affect the normal operation of power system. On the other hand, due to the randomness of the wind and solar irradiation, the output of DG is random, too, which leads to an uncertainty of the harmonic generated by the DG. Thus, probabilistic methods are needed to analyse the impacts of the DG integration. In this work we studied the harmonic voltage probabilistic distribution and the harmonic distortion in distributed network after the distributed photovoltaic (DPV) system integrating in different weather conditions, mainly the sunny day, cloudy day, rainy day and the snowy day. The probabilistic distribution function of the DPV output power in different typical weather conditions could be acquired via the parameter identification method of maximum likelihood estimation. The Monte-Carlo simulation method was adopted to calculate the probabilistic distribution of harmonic voltage content at different frequency orders as well as the harmonic distortion (THD) in typical weather conditions. The case study was based on the IEEE33 system and the results of harmonic voltage content probabilistic distribution as well as THD in typical weather conditions were compared.
Design and Operation of Distribution Markets
NASA Astrophysics Data System (ADS)
Parhizi, Sina
The growing penetration of distributed prosumers especially microgrids poses new challenges to the operation of wholesale markets and distribution power systems. Price spikes and higher uncertainty are among these consequences. Distribution markets are envisioned as a remedy to streamline integration of distributed resources and microgrids in the electricity market. This dissertation offers an analytical formulation of electricity markets in the distribution level, considering various prevailing aspects of the market operation problem. The prevailing challenges in regards to integration of microgrids in the electricity markets are illustrated first, and the distribution market operator (DMO) construct is outlined. The day-ahead scheduling of a microgrid participating in a DMO market is formulated and studied. Then the operation of distribution markets integrated with large numbers of responsive participants is considered, and its transactions with the distribution market participants on one hand, and the wholesale market on the other hand are modeled and studied. The market settlement and clearing, essential in operation of distribution markets, is considered and solved. The pricing mechanism in a distribution market is proposed and the relation of distribution and transmission and distribution prices is studied. A more advanced pricing mechanism considering voltages and reactive power is developed and studied. In order to offer a more accurate pricing structure within the distribution system, a linearized distribution power flow is utilized. The performance of the proposed methods is analyzed and the results are presented. Markets have been recently envisioned to be a suitable instrument for integration of distributed energy resources in the distribution system, but most of the discussions surrounding this topic is at the conceptual level. In this work, it is demonstrated that distribution markets are effective in integrating microgrids and distributed resources in the electricity markets, and an analytical model is presented for design and operation of such markets.
NASA Astrophysics Data System (ADS)
See, S. W.; Balasubramanian, R.; Wang, W.
2006-05-01
Many Southeast Asian countries have been constantly plagued by recurring smoke haze episodes as a result of traditional slash-and-burn practices in agricultural areas to clear crop lands or uncontrolled forest fires. However, our current knowledge on the physiochemical and optical properties of ambient aerosols associated with regional haze phenomenon is still fairly limited. Therefore a comprehensive field study was carried out in Singapore from March 2001 to March 2002 under varying weather conditions to gain a better understanding of the characteristics. The physical (size distribution of mass and number concentrations), chemical (mass concentrations of chemical components: 14 ions, 24 metals, elemental carbon (EC) and organic carbon (OC)), and optical (light absorption (bap) and scattering (bsp) by particles) characteristics of ambient aerosol particles were investigated. The results are reported separately for clear and hazy days by categorizing the days as clear or hazy on the basis of visibility data. It was observed that the average concentrations of PM2.5 and most chemical components increased approximately by a factor of 2 on hazy days. Backward air trajectories together with the hot spot distributions in the region indicated that the degradation in Singapore's air quality on hazy days was attributable to large-scale forest fires in Sumatra. This visibility degradation was quantitatively measured on the basis of the light absorption and scattering by particles. As expected, scattering rather than absorption controlled atmospheric visibility, and PM2.5 particles present on hazy days were more efficient at scattering light than those found on clear days.
ERIC Educational Resources Information Center
Pan American Health Organization, Washington, DC.
At each meeting of the Pan American Health Organization Advisory Committee on Medical Research, a special 1-day session is held on a topic chosen by the committee as being of particular interest. At the 7th meeting, which convened in June of 1968 in Washington, D.C., the session surveyed the origin, present distribution, and principal biological…
An effective model for store and retrieve big health data in cloud computing.
Goli-Malekabadi, Zohreh; Sargolzaei-Javan, Morteza; Akbari, Mohammad Kazem
2016-08-01
The volume of healthcare data including different and variable text types, sounds, and images is increasing day to day. Therefore, the storage and processing of these data is a necessary and challenging issue. Generally, relational databases are used for storing health data which are not able to handle the massive and diverse nature of them. This study aimed at presenting the model based on NoSQL databases for the storage of healthcare data. Despite different types of NoSQL databases, document-based DBs were selected by a survey on the nature of health data. The presented model was implemented in the Cloud environment for accessing to the distribution properties. Then, the data were distributed on the database by applying the Shard property. The efficiency of the model was evaluated in comparison with the previous data model, Relational Database, considering query time, data preparation, flexibility, and extensibility parameters. The results showed that the presented model approximately performed the same as SQL Server for "read" query while it acted more efficiently than SQL Server for "write" query. Also, the performance of the presented model was better than SQL Server in the case of flexibility, data preparation and extensibility. Based on these observations, the proposed model was more effective than Relational Databases for handling health data. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
The legacy and continuity of forest disturbance, succession, and species at the MOFEP sites
Richard Guyette; John M. Kabrick
2002-01-01
Information about the scale, frequency, and legacy of disturbance regimes and their relation to the distribution of forest species is sparse in Ozark ecosystems. Knowledge of these relationships is valuable for understanding present-day forest ecosystem species composition and structure and for predicting how Missouri's forests will respond to management. Here, we...
ERIC Educational Resources Information Center
Flouty, Rosanna Noelle
2016-01-01
Lessons from early academic television courses from the 1950s guide an assessment of current disruptive technologies that shape Massive Open Online Courses (known as MOOCs) and other informal online learning opportunities today. This dissertation explores some of the unique contributing factors that led to the creation of "Sunrise…
ERIC Educational Resources Information Center
Magalula, Cisco
At the time of independence in 1968, education in Swaziland was characterized by poor quality, uneven distribution of schools, high dropout and repeater rates, serious shortages of teachers, and inappropriate and highly academic curricula. This paper describes the status of present-day education in Swaziland in terms of the effect of government…
Gowthaman, Sivakumar; Nakashima, Kazunori; Kawasaki, Satoru
2018-04-04
Incorporating sustainable materials into geotechnical applications increases day by day due to the consideration of impacts on healthy geo-environment and future generations. The environmental issues associated with conventional synthetic materials such as cement, plastic-composites, steel and ashes necessitate alternative approaches in geotechnical engineering. Recently, natural fiber materials in place of synthetic material have gained momentum as an emulating soil-reinforcement technique in sustainable geotechnics. However, the natural fibers are innately different from such synthetic material whereas behavior of fiber-reinforced soil is influenced not only by physical-mechanical properties but also by biochemical properties. In the present review, the applicability of natural plant fibers as oriented distributed fiber-reinforced soil (ODFS) and randomly distributed fiber-reinforced soil (RDFS) are extensively discussed and emphasized the inspiration of RDFS based on the emerging trend. Review also attempts to explore the importance of biochemical composition of natural-fibers on the performance in subsoil reinforced conditions. The treatment methods which enhances the behavior and lifetime of fibers, are also presented. While outlining the current potential of fiber reinforcement technology, some key research gaps have been highlighted at their importance. Finally, the review briefly documents the future direction of the fiber reinforcement technology by associating bio-mediated technological line.
Gowthaman, Sivakumar; Nakashima, Kazunori; Kawasaki, Satoru
2018-01-01
Incorporating sustainable materials into geotechnical applications increases day by day due to the consideration of impacts on healthy geo-environment and future generations. The environmental issues associated with conventional synthetic materials such as cement, plastic-composites, steel and ashes necessitate alternative approaches in geotechnical engineering. Recently, natural fiber materials in place of synthetic material have gained momentum as an emulating soil-reinforcement technique in sustainable geotechnics. However, the natural fibers are innately different from such synthetic material whereas behavior of fiber-reinforced soil is influenced not only by physical-mechanical properties but also by biochemical properties. In the present review, the applicability of natural plant fibers as oriented distributed fiber-reinforced soil (ODFS) and randomly distributed fiber-reinforced soil (RDFS) are extensively discussed and emphasized the inspiration of RDFS based on the emerging trend. Review also attempts to explore the importance of biochemical composition of natural-fibers on the performance in subsoil reinforced conditions. The treatment methods which enhances the behavior and lifetime of fibers, are also presented. While outlining the current potential of fiber reinforcement technology, some key research gaps have been highlighted at their importance. Finally, the review briefly documents the future direction of the fiber reinforcement technology by associating bio-mediated technological line. PMID:29617285
Huang, Shan; Roy, Kaustuv; Valentine, James W; Jablonski, David
2015-04-21
Paleontological data provide essential insights into the processes shaping the spatial distribution of present-day biodiversity. Here, we combine biogeographic data with the fossil record to investigate the roles of parallelism (similar diversities reached via changes from similar starting points), convergence (similar diversities reached from different starting points), and divergence in shaping the present-day latitudinal diversity gradients of marine bivalves along the two North American coasts. Although both faunas show the expected overall poleward decline in species richness, the trends differ between the coasts, and the discrepancies are not explained simply by present-day temperature differences. Instead, the fossil record indicates that both coasts have declined in overall diversity over the past 3 My, but the western Atlantic fauna suffered more severe Pliocene-Pleistocene extinction than did the eastern Pacific. Tropical western Atlantic diversity remains lower than the eastern Pacific, but warm temperate western Atlantic diversity recovered to exceed that of the temperate eastern Pacific, either through immigration or in situ origination. At the clade level, bivalve families shared by the two coasts followed a variety of paths toward today's diversities. The drivers of these lineage-level differences remain unclear, but species with broad geographic ranges during the Pliocene were more likely than geographically restricted species to persist in the temperate zone, suggesting that past differences in geographic range sizes among clades may underlie between-coast contrasts. More detailed comparative work on regional extinction intensities and selectivities, and subsequent recoveries (by in situ speciation or immigration), is needed to better understand present-day diversity patterns and model future changes.
Past Peatland Distribution as an Indicator of Hydroclimate and Temperature
NASA Astrophysics Data System (ADS)
Treat, C. C.; Jones, M.; Lacourse, T.; Payne, R.; Peteet, D. M.; Sannel, B.; Stelling, J.; Talbot, J.; Williams, C. J.; Kleinen, T.; Grosse, G.; Yu, Z.; Finkelstein, S. A.; Broothaerts, N.; Dommain, R.; Kuhry, P.; Lähteenoja, O.; Dalton, A.; Notebaert, B.; Swindles, G. T.; Tarnocai, C.; Verstraeten, G.; Xia, Z.; Brovkin, V.
2016-12-01
Peatlands, wetlands with > 30 cm of organic sediment, cover more than 3 x 106 km2 of the earth surface and have been accumulating carbon and sediments throughout the Holocene. The location of peatland formation and accumulation has been dynamic over time, as peat formation in areas like Alaska and the West Siberian Lowlands preceded peat formation in Fennoscandia and Eastern North America due to more favorable climate for peat formation. Using the geographic distribution of peatlands in the past can indicate general climatic conditions, including hydroclimate, given that the underlying geology is well understood. Peatlands form under a variety of climatic conditions and landscape positions but do not persist under arid conditions, instead requiring either humid conditions or cold temperatures. However, peatlands may have existed in the past in areas not currently suitable for peatland formation and persistence, but where peats can be found at depth within the sediment column. Here we map the locations of histic paleosols, relict peat, and buried peats since the Last Glacial Maximum using a compilation of sites from previous studies. We compare these records of past peatland distribution to present-day peatland distribution. We evaluate regional differences in timing of peatland development in these buried peatlands to the development of extant peatlands. Finally, we compare the timing of past peatland extent to the to modeled paleoclimate during the Quaternary. In addition to implications for paleoclimate, these past peatlands are not well accounted for in present-day soil carbon stocks but could be an important component of deep soil carbon pools.
Guzmán-Guillén, Remedios; Gutiérrez-Praena, Daniel; Risalde, María de los Ángeles; Moyano, Rosario; Prieto, Ana Isabel; Pichardo, Silvia; Jos, Ángeles; Vasconcelos, Vitor; Cameán, Ana María
2014-01-01
Cylindrospermopsin (CYN) is a cytotoxic cyanotoxin produced by several species of freshwater cyanobacteria (i.e., Aphanizomenon ovalisporum). CYN is a tricyclic alkaloid combined with a guanidine moiety. It is well known that CYN inhibits both protein and glutathione synthesis, and also induces genotoxicity and the alteration of different oxidative stress biomarkers. Although the liver and kidney appear to be the main target organs for this toxin based on previous studies, CYN also affects other organs. In the present study, we studied the distribution of CYN in fish (Oreochromis niloticus) under two different exposure scenarios using immunohistochemical (IHC) techniques. In the first method, fish were exposed acutely by intraperitoneal injection or by gavage to 200 µg pure CYN/Kg body weight (bw), and euthanized after 24 h or five days of exposure. In the second method, fish were exposed by immersion to lyophilized A. ovalisporum CYN-producing cells using two concentration levels (10 or 100 µg/L) for two different exposure times (7 or 14 days). The IHC was carried out in liver, kidney, intestine, and gills of fish. Results demonstrated a similar pattern of CYN distribution in both experimental methods. The organ that presented the most immunopositive results was the liver, followed by the kidney, intestine, and gills. Moreover, the immunolabeling signal intensified with increasing time in both assays, confirming the delayed toxicity of CYN, and also with the increment of the dose, as it is shown in the sub-chronic assay. Thus, IHC is shown to be a valuable technique to study CYN distribution in these organisms. PMID:24406981
Gomez-Puerta, Luis Antonio; Lopez-Urbina, Maria Teresa; Garcia, Hector Hugo; Gonzalez, Armando Emiliano
2014-03-01
The present study evaluated the capacity of Ammophorus rubripes beetles to carry Taenia solium eggs, in terms of duration and viability of eggs in their digestive system. One hundred beetles were distributed into five polyethylene boxes, and then they were infected with T. solium eggs. Gravid proglottids of T. solium were crushed and then mixed with cattle feces. One gram of this mixture was placed in each box for 24 hours, after which each group of beetles was transferred into a new clean box. Then, five beetles were dissected every three days. Time was strongly associated with viability (r=0.89; P<0.001) and the calculated time to cero viability is 36 days. The eggs in the intestinal system of each beetle were counted and tested for viability. Taenia solium eggs were present in the beetle's digestive system for up to 39 days (13th sampling day out of 20), gradually reducing in numbers and viability, which was 0 on day 36 post-infection. Egg viability was around 40% up to day 24 post-infection, with a median number of eggs of 11 per beetle at this time. Dung beetles may potentially contribute towards dispersing T. solium eggs in endemic areas.
Gomez-Puerta, Luis Antonio; Lopez-Urbina, Maria Teresa; Garcia, Hector Hugo; Gonzalez, Armando Emiliano
2015-01-01
The present study evaluated the capacity of Ammophorus rubripes beetles to carry Taenia solium eggs, in terms of duration and viability of eggs in their digestive system. One hundred beetles were distributed into five polyethylene boxes, and then they were infected with T. solium eggs. Gravid proglottids of T. solium were crushed and then mixed with cattle feces. One gram of this mixture was placed in each box for 24 hours, after which each group of beetles was transferred into a new clean box. Then, five beetles were dissected every three days. Time was strongly associated with viability (r=0.89; P<0.001) and the calculated time to cero viability is 36 days. The eggs in the intestinal system of each beetle were counted and tested for viability. Taenia solium eggs were present in the beetle’s digestive system for up to 39 days (13th sampling day out of 20), gradually reducing in numbers and viability, which was 0 on day 36 post-infection. Egg viability was around 40% up to day 24 post-infection, with a median number of eggs of 11 per beetle at this time. Dung beetles may potentially contribute towards dispersing T. solium eggs in endemic areas. PMID:24728368
Development of the oxytalan fiber system in the periodontal space of rat incisors.
Inoue, Kouji; Hara, Yaiko; Kuroda, Noriyuki; Sato, Tetsuji
2013-10-01
The present study clarifies developmental organization of the oxytalan fiber system in the periodontal space of both the enamel (labial) and cementum (lingual) sides of rat incisors. The number of oxytalan fibers per unit area (μm(2)) was counted in rat incisors at stages of embryonic day 20 (E20) to postnatal day 35 (P35). Oxytalan fibers in the periodontal space of the enamel side were apt to decrease in number during the postnatal period, whereas their number remained almost unchanged on the cementum side during the developmental period. When the incisor emerged through the gum at P11, thinner oxytalan fibers distributed in the apical growing periodontium of the cementum side seemed to be fused with one another to become thicker fibers as has been reported for rat molars (Inoue et al., 2012). Thus, the oxytalan fiber system in the periodontal space represented significant differences in its distributional density between the enamel and cementum sides after E23. At the stage of P35, oxytalan fibers presented significantly denser distribution in all territories of the periodontal ligament of the cementum side versus the enamel side. The present findings claim that the oxytalan fiber system might bind the tooth to the periodontal ligament and provide equilibrium of vascular system and control of blood flow in the periodontal ligament of the cementum side, while it might exclusively regulate the high level of physiologically adapted vasculature in the periodontal space of the enamel side. Copyright © 2013 Elsevier GmbH. All rights reserved.
Potential use of edible crops in the phytoremediation of endosulfan residues in soil.
Mitton, Francesca M; Gonzalez, Mariana; Monserrat, José M; Miglioranza, Karina S B
2016-04-01
Endosulfan is a persistent and toxic organochlorine pesticide of banned or restricted use in several countries. It has been found in soil, water, and air and is bioaccumulated and magnified in ecosystems. Phytoremediation is a technology that promises effective and inexpensive cleanup of contaminated hazardous sites. The potential use of tomato, sunflower, soybean and alfalfa species to remove endosulfan from soil was investigated. All species were seeded and grown in endosulfan-spiked soils (8000 ng g(-1) dry weight) for 15 and 60 days. The phytoremediation potential was evaluated by studying the endosulfan levels and distribution in the soil-plant system, including the evaluation of soil dehydrogenase activity and toxic effects on plants. Plant endosulfan uptake leads to lower insecticide levels in the rhizosphere with regards to bulk soil or near root soil at 15 days of growth. Furthermore, plant growth-induced physical-chemical changes in soil were evidenced by differences in soil dehydrogenase activity and endosulfan metabolism. Sunflower showed differences in the uptake and distribution of endosulfan with regard to the other species, with a distribution pesticide pattern of aerial tissues > roots at 15 days of growth. Moreover, at 60 days, sunflower presented the highest pesticide levels in roots and leaves along with the highest phytoextraction capacity. Lipid peroxidation levels correlated positively with endosulfan accumulation, reflecting the negative effect of this insecticide on plant tissues. Considering biomass production and accumulation potential, in conjunction with the reduction of soil pesticide levels, sunflower plants seem to be the best phytoremediation candidate for endosulfan residues in soils. Copyright © 2016 Elsevier Ltd. All rights reserved.
Distributed Multisensor Data Fusion under Unknown Correlation and Data Inconsistency
Abu Bakr, Muhammad; Lee, Sukhan
2017-01-01
The paradigm of multisensor data fusion has been evolved from a centralized architecture to a decentralized or distributed architecture along with the advancement in sensor and communication technologies. These days, distributed state estimation and data fusion has been widely explored in diverse fields of engineering and control due to its superior performance over the centralized one in terms of flexibility, robustness to failure and cost effectiveness in infrastructure and communication. However, distributed multisensor data fusion is not without technical challenges to overcome: namely, dealing with cross-correlation and inconsistency among state estimates and sensor data. In this paper, we review the key theories and methodologies of distributed multisensor data fusion available to date with a specific focus on handling unknown correlation and data inconsistency. We aim at providing readers with a unifying view out of individual theories and methodologies by presenting a formal analysis of their implications. Finally, several directions of future research are highlighted. PMID:29077035
Mistaking geography for biology: inferring processes from species distributions.
Warren, Dan L; Cardillo, Marcel; Rosauer, Dan F; Bolnick, Daniel I
2014-10-01
Over the past few decades, there has been a rapid proliferation of statistical methods that infer evolutionary and ecological processes from data on species distributions. These methods have led to considerable new insights, but they often fail to account for the effects of historical biogeography on present-day species distributions. Because the geography of speciation can lead to patterns of spatial and temporal autocorrelation in the distributions of species within a clade, this can result in misleading inferences about the importance of deterministic processes in generating spatial patterns of biodiversity. In this opinion article, we discuss ways in which patterns of species distributions driven by historical biogeography are often interpreted as evidence of particular evolutionary or ecological processes. We focus on three areas that are especially prone to such misinterpretations: community phylogenetics, environmental niche modelling, and analyses of beta diversity (compositional turnover of biodiversity). Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.
Annual and seasonal distribution of day and night Land Surface Temperature trend over Greece.
NASA Astrophysics Data System (ADS)
Lakshmi, V.; Gemitzi, A.; Eleftheriou, D.; Kalea, A.; Kalmintzis, G.; Kiachidis, K.; Koumadoraki, P.; Mpantasis, C.; Spathara, M. E.; Tsolaki, A.; Tzampazidou, M. I.
2017-12-01
Climate change is one of the most challenging research topics during the last few decades, as temperature rise has already posed a significant impact on earth's functions affecting thus all life of the planet. The present study investigates the distribution of day and night Land Surface Temperature (LST) trends over Greece, a country in Mediterranean area which is identified as one of the main ``hot-spots" of climate change projections. Remotely sensed LST data were obtained from MODIS sensor in the form of 8-day composites of day and night values at a resolution of 1km for a 17-year period, i.e. from 2000 to 2017. Spatial aggregates of 10km x 10km were computed and the annual and seasonal temporal trends were determined for each one of those sub-areas. Results showed that annual trends of daily LST in the majority of areas demonstrated decrease ranging from -1*10-2 oC to -1.3*10-3 oC, with some sporadic parts showing a slight increase. A totally different outcome is observed in the fate of night LST, with all areas over Greece demonstrating increasing annual trends ranging from 4.6 * 10-5 oC to 3.1 * 10-3 oC, with highest values in the South-East parts of the country. Seasonal trends in day and night LST showed the same pattern, i.e., a general decrease in the day LST and a definite increase in night. An interesting finding is the increase in winter LST trends observed both for day and night LST, indicating that the absolute minimum annual LST observed during winter in Greece increases. Our results also indicate that the difference between the day and night LST is decreasing.
What rainfall events trigger landslides on the West Coast US?
NASA Astrophysics Data System (ADS)
Biasutti, Michela; Seager, Richard; Kirschbaum, Dalia
2016-04-01
A dataset of landslide occurrences compiled by collating google news reports covers 9 full years of data. We show that, while this compilation cannot provide consistent and widespread monitoring everywhere, it is adequate to capture the distribution of events in the major urban areas of the West Coast US and it can be used to provide a quantitative relationship between landslides and rainfall events. The case of the Seattle metropolitan area is presented as an example. The landslide dataset shows a clear seasonality in landslide occurrence, corresponding to the seasonality of rainfall, modified by the accumulation of soil moisture as winter progresses. Interannual variability of landslide occurrences is also linked to interannual variability of monthly rainfall. In most instances, landslides are clustered on consecutive days or at least within the same pentad and correspond to days of large rainfall accumulation at the regional scale. A joint analysis of the landslide data and of the high-resolution PRISM daily rainfall accumulation shows that on days when landslides occurred, the distribution of rainfall was shifted, with rainfall accumulation higher than 10mm/day being more common. Accumulations above 50mm/day much increase the probability of landslides, including the possibility of a major landslide event (one with multiple landslides in a day). The synoptic meteorological conditions associated with these major events show a mid-tropospheric ridge to the south of the target area steering a surface low and bringing enhanced precipitable water towards the Pacific North West. The interaction of the low-level flow with the local orography results in instances of a strong Puget Sound Convergence Zone, with widespread rainfall accumulation above 30mm/day and localized maxima as high as 100mm/day or more.
Size distribution and sorption of polychlorinated biphenyls during haze episodes
NASA Astrophysics Data System (ADS)
Zhu, Qingqing; Liu, Guorui; Zheng, Minghui; Zhang, Xian; Gao, Lirong; Su, Guijin; Liang, Yong
2018-01-01
There is a lack of studies on the size distribution of polychlorinated biphenyls (PCBs) during haze days, and their sorption mechanisms on aerosol particles remain unclear. In this study, PCBs in particle-sized aerosols from urban atmospheres of Beijing, China were investigated during haze and normal days. The concentrations, gas/particle partitioning, size distribution, and associated human daily intake of PCBs via inhalation were compared during haze days and normal days. Compared with normal days, higher particle mass-associated PCB levels were measured during haze days. The concentrations of ∑PCBs in particulate fractions were 11.9-134 pg/m3 and 6.37-14.9 pg/m3 during haze days and normal days, respectively. PCBs increased with decreasing particle size (>10 μm, 10-2.5 μm, 2.5-1.0 μm, and ≤1.0 μm). During haze days, PCBs were overwhelmingly associated with a fine particle fraction of ≤1.0 μm (64.6%), while during normal days the contribution was 33.7%. Tetra-CBs were the largest contributors (51.8%-66.7%) both in the gas and particle fractions during normal days. The profiles in the gas fraction were conspicuously different than those in the PM fractions during haze days, with di-CBs predominating in the gas fraction and higher homologues (tetra-CBs, penta-CBs, and hexa-CBs) concurrently accounting for most of the PM fractions. The mean-normalized size distributions of particulate mass and PCBs exhibited unimodal patterns, and a similar trend was observed for PCBs during both days. They all tended to be in the PM fraction of 1.0-2.5 μm. Adsorption might be the predominating mechanism for the gas-particle partitioning of PCBs during haze days, whereas absorption might be dominative during normal days.
Brito, Nara Macedo Botelho; Carvalho, Rita de Kássia Vidigal; Matos, Lia Tavares de Moura Brasil; Lobato, Rodolfo Costa; Brito, Rosângela Baía
2009-01-01
Verify the effect of oophorectomy on the evolution of the Walker 256 tumor inoculated into the vagina and cervix of female rats. Ten Wistar, female rats were used, distributed into two groups with 05 animals each: Tumor group (TG): Rats inoculated with Walker 256 tumor; Oophorectomy group (OG): oophorectomized rats inoculated with Walker 256 tumor. The day before the tumor vaginal inoculation, acetic acid was inoculated into the vaginas of both groups of rats; the following day, the vaginal walls were scarified with an endocervix brush, and then Walker 256 tumor was inoculated. After 12 days, the tumor was removed together with the vagina and uterine horns for macro and microscopic analyses. The data were submitted to statistical analyses. There was no statistical difference between the two groups; however it was observed that the behavior of tumor growth on the OG group presented greater invasion, compromising the uterine horns. The results of the study on the GO group presented a macroscopic behavior different from the TG group, however, both of them presented similar development in terms of tumor mass.
NASA Astrophysics Data System (ADS)
Ortega, Ivan; Sinreich, Roman; Volkamer, Rainer
2014-05-01
We present results of 2 dimensional Multi Axis-DOAS (2D-MAX-DOAS) measurements to infer 3-dimensional measurements of trace gases by characterizing boundary layer vertical profiles and near surface azimuth horizontal distribution of NO2 (14 angles covering 360°). We combine the established optimal estimation inversion with a new parameterization approach; the first method to derive NO2 tropospheric vertical profiles and boundary layer height and the second one to retrieve the azimuth horizontal distribution of near surface NO2 mixing ratios, both at multiple wavelengths (350 nm, 450 nm, and 560 nm). This was conducted for three cloud-free days in the framework of the intensive Multi Axis DOAS Comparison campaign for Aerosols and Trace gases (MAD-CAT) in Mainz, Germany 2013. By retrieving NO2 at multiple wavelengths range-resolved distributions of NO2 are derived using an 'Onion-peeling' approach, i.e., exploiting the fact that the optical path lengths at different wavelengths probe different horizontal air masses. We also measure glyoxal (CHOCHO) and formaldehyde (HCHO) distributions, and present to our knowledge the first 3-dimesional trace-gas distribution measurements of CHOCHO by a ground-based instrument. We expand the 2D-MAX-DOAS capabilities to calculate azimuth ratios of HCHO-to-NO2 (RFN) and CHOCHO-to-NO2 (RGN) to pinpoint volatile organic compound (VOC) oxidation chemistry and CHOCHO-to-HCHO (RGF) ratios as an indicator of biogenic and/or anthropogenic VOC emissions. The results of RFN correlate well with RGN and we identify azimuth variations that indicate gradients in the VOC/NOx chemistry that leads to O3 and secondary aerosol production. While there is a clear diurnal pattern in the RFN and RGN, no such variations are observed in the RGF, which shows rather constant values below 0.04 throughout the day, consistent with previous measurements, and indicative of urban air masses.
Winter Distribution of On-road NO2 Concentration in Hong Kong
NASA Astrophysics Data System (ADS)
Zhu, Y.; Chan, K. L.; Boll, J.; Schütt, A. M. N.; Lipkowitsch, I.; Wenig, M.
2017-12-01
In this study, we investigated the spatial distribution of on road NO2 concentration using Cavity-Enhanced Differential Optical Absorption Spectroscopy (DOAS). We performed two measurement campaigns in winter 2010 and 2017. Air pollution is a severe problem for many big cities, especially in Asia. Traffic emission is the primary source of urban pollutants. As Hong Kong is one of the most densely populated cities in the world, many inhabitants are exposed to accumulated pollutants in street canyons. Our mobile measurements were performed for a week in December, 2010 and March, 2017. Additionally, long term air pollution data measured by a long-path DOAS (LP-DOAS) and the Environment Protection Department (EPD) air quality monitoring network were used to investigate the long term trend and seasonal variations of atmospheric NO2 in Hong Kong.The experiment setup and preliminary results of mobile measurements are presented. The measurements were performed along a fixed route which covers most of the urban area. We assembled a NO2 concentration map 2 to 3 times per day in order to cover both morning and evening rush hours. In order to construct a consistent map, we use coinciding LP-DOAS NO2 data to correct for the diurnal cycle. Furthermore, the spatial and temporal distribution of NO2 changes with the day of the week. Traffic load is highly dependent on human activities which typically fall into a 7 days cycle. Therefore, we have analyzed the weekly pattern of on road NO2 distribution to see the differences between anthropogenic emissions during weekdays and weekend.
Vitamin D3 distribution and status in the body.
Heaney, Robert P; Horst, Ronald L; Cullen, Diane M; Armas, Laura A G
2009-06-01
To estimate the amount, type, and tissue distribution of vitamin D in the adult body under typical inputs. Review and reanalysis of published measurements and analysis of tissue samples from growing pigs raised in confinement on diets providing about 2000 IU vitamin D/day. Cholecalciferol and 25-hydroxyvitamin D [25(OH)D] concentration measured by HPLC. Mean serum 25(OH)D in all studies combined was 45 nmol/L. At the level of vitamin D repletion represented by this concentration, total body vitamin D would be 14,665 IU for a 70 kg adult woman. 65% of this total was present as native cholecalciferol and 35% as 25(OH)D. Nearly three-quarters of the cholecalciferol was in fat, while 25(OH)D was more evenly distributed throughout the body (20% in muscle, 30% in serum, 35% in fat, and 15% in all other tissues). At the daily vitamin D consumption rates in these animals total body stores provided only a approximately 7-day reserve. At total intakes on the order of 2000 IU/day, an adult has very little vitamin D reserve, despite intakes 10x the current recommendations. Those recommended inputs need to be increased by at least an order of magnitude. Food tables that fail to take into account 25(OH)D content of various meat products lead to underestimation of dietary vitamin D intake.
Zhang, Xian; Zheng, Minghui; Liang, Yong; Liu, Guorui; Zhu, Qingqing; Gao, Lirong; Liu, Wenbin; Xiao, Ke; Sun, Xu
2016-12-15
Little information is available on the distributions of airborne polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) during haze days. In this study, PCDD/F concentrations, particle size distributions, and gas-particle partitioning in a Beijing suburban area during haze days and normal days were investigated. High PCDD/F concentrations, 3979-74,702fgm -3 (173-3885fgI-TEQm -3 ), were found during haze days and ~98% of the PCDD/Fs were associated with particles. Most PCDD/F congeners (>90%) were associated with particles. PCDD/F concentrations increased as particle sizes decreased and 95% of the particle-bound PCDD/Fs were associated with inhalable fine particles with aerodynamic diameters<2.5μm. PCDD/Fs were mainly absorbed in the particles and the Harner-Bidleman model predicted the particulate fractions of the PCDD/F congeners in the air samples well. The investigated PCDD/F concentrations and particle-bound distributions were different during normal days than during haze days. Temporal airborne PCDD/F trends in a suburban area during haze conditions could support better understanding of the exposure risk posed by toxic PCDD/Fs associated with fine particles. Copyright © 2016 Elsevier B.V. All rights reserved.
Stubbe, Tobias; Ebner, Friederike; Richter, Daniel; Randolf Engel, Odilo; Klehmet, Juliane; Royl, Georg; Meisel, Andreas; Nitsch, Robert; Meisel, Christian; Brandt, Christine
2013-01-01
Local and peripheral immune responses are activated after ischemic stroke. In our present study, we investigated the temporal distribution, location, induction, and function of regulatory T cells (Tregs) and the possible involvement of microglia, macrophages, and dendritic cells after middle cerebral artery occlusion (MCAO). C57BL/6J and Foxp3EGFP transgenic mice were subjected to 30 minutes MCAO. On days 7, 14, and 30 after MCAO, Tregs and antigen presenting cells were analyzed using fluorescence activated cell sorting multicolor staining and immunohistochemistry. A strong accumulation of Tregs was observed on days 14 and 30 in the ischemic hemisphere accompanied by the elevated presence and activation of microglia. Dendritic cells and macrophages were found on each analyzed day. About 60% of Foxp3+ Tregs in ischemic hemispheres were positive for the proliferation marker Ki-67 on days 7 and 14 after MCAO. The transfer of naive CD4+ cells depleted of Foxp3+ Tregs into RAG1−/− mice 1 day before MCAO did not lead to a de novo generation of Tregs 14 days after surgery. After depletion of CD25+ Tregs, no changes regarding neurologic outcome were detected. The sustained presence of Tregs in the brain after MCAO indicates a long-lasting immunological alteration and involvement of brain cells in immunoregulatory mechanisms. PMID:22968321
Stubbe, Tobias; Ebner, Friederike; Richter, Daniel; Engel, Odilo; Randolf Engel, Odilo; Klehmet, Juliane; Royl, Georg; Meisel, Andreas; Nitsch, Robert; Meisel, Christian; Brandt, Christine
2013-01-01
Local and peripheral immune responses are activated after ischemic stroke. In our present study, we investigated the temporal distribution, location, induction, and function of regulatory T cells (Tregs) and the possible involvement of microglia, macrophages, and dendritic cells after middle cerebral artery occlusion (MCAO). C57BL/6J and Foxp3(EGFP) transgenic mice were subjected to 30 minutes MCAO. On days 7, 14, and 30 after MCAO, Tregs and antigen presenting cells were analyzed using fluorescence activated cell sorting multicolor staining and immunohistochemistry. A strong accumulation of Tregs was observed on days 14 and 30 in the ischemic hemisphere accompanied by the elevated presence and activation of microglia. Dendritic cells and macrophages were found on each analyzed day. About 60% of Foxp3(+) Tregs in ischemic hemispheres were positive for the proliferation marker Ki-67 on days 7 and 14 after MCAO. The transfer of naive CD4(+) cells depleted of Foxp3(+) Tregs into RAG1(-/-) mice 1 day before MCAO did not lead to a de novo generation of Tregs 14 days after surgery. After depletion of CD25(+) Tregs, no changes regarding neurologic outcome were detected. The sustained presence of Tregs in the brain after MCAO indicates a long-lasting immunological alteration and involvement of brain cells in immunoregulatory mechanisms.
Thomas, Kathryn A.; Guertin, Patricia P.; Gass, Leila
2012-01-01
The authors developed spatial models of the predicted modern-day suitable habitat (SH) of 166 dominant and indicator plant species of the southwestern United States (herein referred to as the Southwest) and then conducted a coarse assessment of potential future changes in the distribution of their suitable habitat under three climate-change scenarios for two time periods. We used Maxent-based spatial modeling to predict the modern-day and future scenarios of SH for each species in an over 342-million-acre area encompassing all or parts of six states in the Southwest--Arizona, California, Colorado, Nevada, New Mexico, and Utah. Modern-day SH models were predicted by our using 26 annual and monthly average temperature and precipitation variables, averaged for the years 1971-2000. Future SH models were predicted for each species by our using six climate models based on application of the average of 16 General Circulation Models to Intergovernmental Panel on Climate Change emission scenarios B1, A1B, and A2 for two time periods, 2040 to 2069 and 2070 and 2100, referred to respectively as the 2050 and 2100 time periods. The assessment examined each species' vulnerability to loss of modern-day SH under future climate scenarios, potential to gain SH under future climate scenarios, and each species' estimated risk as a function of both vulnerability and potential gains. All 166 species were predicted to lose modern-day SH in the future climate change scenarios. In the 2050 time period, nearly 30 percent of the species lost 75 percent or more of their modern-day suitable habitat, 21 species gained more new SH than their modern-day SH, and 30 species gained less new SH than 25 percent of their modern-day SH. In the 2100 time period, nearly half of the species lost 75 percent or more of their modern-day SH, 28 species gained more new SH than their modern-day SH, and 34 gained less new SH than 25 percent of their modern-day SH. Using nine risk categories we found only two species were in the least risk category, while 20 species were in the highest risk category. The assessment showed that species respond independently to predicted climate change, suggesting that current plant assemblages may disassemble under predicted climate change scenarios. This report presents the results for each species in tables (Appendix A) and maps (14 for each species) in Appendix B.
Distributed retrieval practice promotes superior recall of anatomy information.
Dobson, John L; Perez, Jose; Linderholm, Tracy
2017-07-01
Effortful retrieval produces greater long-term recall of information when compared to studying (i.e., reading), as do learning sessions that are distributed (i.e., spaced apart) when compared to those that are massed together. Although the retrieval and distributed practice effects are well-established in the cognitive science literature, no studies have examined their additive effect with regard to learning anatomy information. The aim of this study was to determine how the benefits of retrieval practice vary with massed versus distributed learning. Participants used the following strategies to learn sets of skeletal muscle anatomy: (1) studying on three different days over a seven day period (SSSS 7,2,0 ), (2) studying and retrieving on three different days over a seven day period (SRSR 7,2,0 ), (3) studying on two different days over a two day period (SSSSSS 2,0 ), (4) studying and retrieving on two separate days over a two day period (SRSRSR 2,0 ), and (5) studying and retrieving on one day (SRx6 0 ). All strategies consisted of 12 learning phases and lasted exactly 24 minutes. Muscle information retention was assessed via free recall and using repeated measures ANOVAs. A week after learning, the recall scores were 24.72 ± 3.12, 33.88 ± 3.48, 15.51 ± 2.48, 20.72 ± 2.94, and 12.86 ± 2.05 for the SSSS 7,2,0 , SRSR 7,2,0 , SSSSSS 2,0 , STSTST 2,0 , and SRx6 0 strategies, respectively. In conclusion, the distributed strategies produced significantly better recall than the massed strategies, the retrieval-based strategies produced significantly better recall than the studying strategies, and the combination of distributed and retrieval practice generated the greatest recall of anatomy information. Anat Sci Educ 10: 339-347. © 2016 American Association of Anatomists. © 2016 American Association of Anatomists.
Atlantic meridional overturning circulation during the Last Glacial Maximum.
Lynch-Stieglitz, Jean; Adkins, Jess F; Curry, William B; Dokken, Trond; Hall, Ian R; Herguera, Juan Carlos; Hirschi, Joël J-M; Ivanova, Elena V; Kissel, Catherine; Marchal, Olivier; Marchitto, Thomas M; McCave, I Nicholas; McManus, Jerry F; Mulitza, Stefan; Ninnemann, Ulysses; Peeters, Frank; Yu, Ein-Fen; Zahn, Rainer
2007-04-06
The circulation of the deep Atlantic Ocean during the height of the last ice age appears to have been quite different from today. We review observations implying that Atlantic meridional overturning circulation during the Last Glacial Maximum was neither extremely sluggish nor an enhanced version of present-day circulation. The distribution of the decay products of uranium in sediments is consistent with a residence time for deep waters in the Atlantic only slightly greater than today. However, evidence from multiple water-mass tracers supports a different distribution of deep-water properties, including density, which is dynamically linked to circulation.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Whicker, F.W.; Pinder, J.E. III; Bowling, J.W.
1989-05-01
The gradual senescence of present-day operating nuclear facilities, and resultant contamination of aquatic and terrestrial ecosystems, emphasize the importance of understanding the behavior of radionuclides in the environment. Observations and deductions concerning mechanisms of radionuclide transport can contribute significantly to knowledge of fundamental ecological processes. This study emphasized the ecosystem-level distribution of several long-lived radionuclides in an abandoned reactor cooling impoundment after a twenty year period of chemical and biological equilibration. 90 refs., 14 figs., 5 tabs.
Quaternary coral reef refugia preserved fish diversity.
Pellissier, Loïc; Leprieur, Fabien; Parravicini, Valeriano; Cowman, Peter F; Kulbicki, Michel; Litsios, Glenn; Olsen, Steffen M; Wisz, Mary S; Bellwood, David R; Mouillot, David
2014-05-30
The most prominent pattern in global marine biogeography is the biodiversity peak in the Indo-Australian Archipelago. Yet the processes that underpin this pattern are still actively debated. By reconstructing global marine paleoenvironments over the past 3 million years on the basis of sediment cores, we assessed the extent to which Quaternary climate fluctuations can explain global variation in current reef fish richness. Comparing global historical coral reef habitat availability with the present-day distribution of 6316 reef fish species, we find that distance from stable coral reef habitats during historical periods of habitat loss explains 62% of the variation in fish richness, outweighing present-day environmental factors. Our results highlight the importance of habitat persistence during periods of climate change for preserving marine biodiversity. Copyright © 2014, American Association for the Advancement of Science.
NASA Technical Reports Server (NTRS)
Hiser, H. W.; Senn, H. V.; Bukkapatnam, S. T.; Akyuzlu, K.
1977-01-01
The use of cloud images in the visual spectrum from the SMS/GOES geostationary satellites to determine the hourly distribution of sunshine on a mesoscale in the continental United States excluding Alaska is presented. Cloud coverage and density as a function of time of day and season are evaluated through the use of digital data processing techniques. Low density cirrus clouds are less detrimental to solar energy collection than other types; and clouds in the morning and evening are less detrimental than those during midday hours of maximum insolation. Seasonal geographic distributions of cloud cover/sunshine are converted to langleys of solar radiation received at the earth's surface through relationships developed from long term measurements at six widely distributed stations.
Forecasting the duration of volcanic eruptions: an empirical probabilistic model
NASA Astrophysics Data System (ADS)
Gunn, L. S.; Blake, S.; Jones, M. C.; Rymer, H.
2014-01-01
The ability to forecast future volcanic eruption durations would greatly benefit emergency response planning prior to and during a volcanic crises. This paper introduces a probabilistic model to forecast the duration of future and on-going eruptions. The model fits theoretical distributions to observed duration data and relies on past eruptions being a good indicator of future activity. A dataset of historical Mt. Etna flank eruptions is presented and used to demonstrate the model. The data have been compiled through critical examination of existing literature along with careful consideration of uncertainties on reported eruption start and end dates between the years 1300 AD and 2010. Data following 1600 is considered to be reliable and free of reporting biases. The distribution of eruption duration between the years 1600 and 1669 is found to be statistically different from that following it and the forecasting model is run on two datasets of Mt. Etna flank eruption durations: 1600-2010 and 1670-2010. Each dataset is modelled using a log-logistic distribution with parameter values found by maximum likelihood estimation. Survivor function statistics are applied to the model distributions to forecast (a) the probability of an eruption exceeding a given duration, (b) the probability of an eruption that has already lasted a particular number of days exceeding a given total duration and (c) the duration with a given probability of being exceeded. Results show that excluding the 1600-1670 data has little effect on the forecasting model result, especially where short durations are involved. By assigning the terms `likely' and `unlikely' to probabilities of 66 % or more and 33 % or less, respectively, the forecasting model based on the 1600-2010 dataset indicates that a future flank eruption on Mt. Etna would be likely to exceed 20 days (± 7 days) but unlikely to exceed 86 days (± 29 days). This approach can easily be adapted for use on other highly active, well-documented volcanoes or for different duration data such as the duration of explosive episodes or the duration of repose periods between eruptions.
Associated Υ+γ production at the LHC in the kt-factorization approach
NASA Astrophysics Data System (ADS)
Baranov, S. P.
2010-09-01
In the framework of the kt-factorization approach, the photon-associated production of Υ mesons at the present-day LHC conditions is studied. The differential cross sections and polarization parameters are calculated in the “helicity” and Collins-Soper systems. Special attention is paid to the effect of experimental cuts that can dramatically change the visible lepton angular distributions.
Associated ϒ + γ production at the LHC in the k-factorization approach
NASA Astrophysics Data System (ADS)
Baranov, S. P.
2011-05-01
In the framework of k-factorization approach, the photon-associated production of ϒ mesons at the present-day LHC conditions is studied. The differential cross sections and polarization parameters are calculated in the 'helicity' and Collins-Soper systems. Special attention is paid to the effect of experimental cuts that can dramatically change the visible lepton angular distributions.
New observations of the low energy proton inner belt
NASA Astrophysics Data System (ADS)
Guild, T. B.; Mazur, J. E.; Looper, M. D.; Blake, J. B.
2013-12-01
We present preliminary results of the trapped low energy (6-32 MeV) proton population in the inner radiation belt (L>1.8) from May, 2008 through present. These observations were made by the High Linear Energy Transfer (HiLET) proton telescope, part of the TWIN-ES instrument suite on the TWINS-2 spacecraft. This collimated telescope measures pitch-angle-resolved proton fluxes as it rises through the inner radiation belt twice per day. We present pitch angle distributions of low energy protons as a function of L, and show how the flux and pitch angle distributions change from the deep solar minimum of 2009 through the rising phase of solar cycle 24. Particular emphasis will be given to inner belt dynamics throughout this interval, both gradual and abrupt, and a discussion of the candidate processes responsible for these changes will be given.
Variety and volatility in financial markets
NASA Astrophysics Data System (ADS)
Lillo, Fabrizio; Mantegna, Rosario N.
2000-11-01
We study the price dynamics of stocks traded in a financial market by considering the statistical properties of both a single time series and an ensemble of stocks traded simultaneously. We use the n stocks traded on the New York Stock Exchange to form a statistical ensemble of daily stock returns. For each trading day of our database, we study the ensemble return distribution. We find that a typical ensemble return distribution exists in most of the trading days with the exception of crash and rally days and of the days following these extreme events. We analyze each ensemble return distribution by extracting its first two central moments. We observe that these moments fluctuate in time and are stochastic processes, themselves. We characterize the statistical properties of ensemble return distribution central moments by investigating their probability density functions and temporal correlation properties. In general, time-averaged and portfolio-averaged price returns have different statistical properties. We infer from these differences information about the relative strength of correlation between stocks and between different trading days. Last, we compare our empirical results with those predicted by the single-index model and we conclude that this simple model cannot explain the statistical properties of the second moment of the ensemble return distribution.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-03-22
... Service; Limited 90-Day Waiver for the Distribution of Anhydrous Ammonia in Agricultural Operations AGENCY... anhydrous ammonia from any distribution point to a local farm retailer or to the ultimate consumer, and from... anhydrous ammonia during the 2010 spring planting season. The Agency has determined that the waiver would...
Wang, Honglei; Zhu, Bin; Shen, Lijuan; Kang, Hanqing
2012-01-01
To investigate the impact on urban air pollution by crop residual burning outside Nanjing, aerosol concentration, pollution gas concentration, mass concentration, and water-soluble ion size distribution were observed during one event of November 4-9, 2010. Results show that the size distribution of aerosol concentration is bimodal on pollution days and normal days, with peak values at 60-70 and 200-300 nm, respectively. Aerosol concentration is 10(4) cm(-3) x nm(-1) on pollution days. The peak value of spectrum distribution of aerosol concentration on pollution days is 1.5-3.3 times higher than that on a normal day. Crop residual burning has a great impact on the concentration of fine particles. Diurnal variation of aerosol concentration is trimodal on pollution days and normal days, with peak values at 03:00, 09:00 and 19:00 local standard time. The first peak is impacted by meteorological elements, while the second and third peaks are due to human activities, such as rush hour traffic. Crop residual burning has the greatest impact on SO2 concentration, followed by NO2, O3 is hardly affected. The impact of crop residual burning on fine particles (< 2.1 microm) is larger than on coarse particles (> 2.1 microm), thus ion concentration in fine particles is higher than that in coarse particles. Crop residual burning leads to similar increase in all ion components, thus it has a small impact on the water-soluble ions order. Crop residual burning has a strong impact on the size distribution of K+, Cl-, Na+, and F- and has a weak impact on the size distributions of NH4+, Ca2+, NO3- and SO4(2-).
Overset grid applications on distributed memory MIMD computers
NASA Technical Reports Server (NTRS)
Chawla, Kalpana; Weeratunga, Sisira
1994-01-01
Analysis of modern aerospace vehicles requires the computation of flowfields about complex three dimensional geometries composed of regions with varying spatial resolution requirements. Overset grid methods allow the use of proven structured grid flow solvers to address the twin issues of geometrical complexity and the resolution variation by decomposing the complex physical domain into a collection of overlapping subdomains. This flexibility is accompanied by the need for irregular intergrid boundary communication among the overlapping component grids. This study investigates a strategy for implementing such a static overset grid implicit flow solver on distributed memory, MIMD computers; i.e., the 128 node Intel iPSC/860 and the 208 node Intel Paragon. Performance data for two composite grid configurations characteristic of those encountered in present day aerodynamic analysis are also presented.
Aerosol optical properties during firework, biomass burning and dust episodes in Beijing
NASA Astrophysics Data System (ADS)
Yu, Xingna; Shi, Chanzhen; Ma, Jia; Zhu, Bin; Li, Mei; Wang, Jing; Yang, Suying; Kang, Na
2013-12-01
In order to characterize the aerosol optical properties during different pollution episodes that occurred in Beijing, the aerosol loading, scattering, and size distributions are presented using solar and sky radiance measurements from 2001 to 2010 in this paper. A much higher aerosol loading than the background level was observed during the pollution episodes. The average aerosol optical depth (AOD) is largest during dust episodes coupled with the lowest Ångström exponent (α), while higher AOD and lower α were more correlated with firework and biomass burning days. The total mean AOD at 440, 675, 870 and 1020 nm were 0.24, 0.49, 0.64 and 1.38 in the clean, firework display, biomass burning and dust days, respectively. The mean α for dust days was 0.51 and exceeded 1.1 for the remaining episodes. The size distribution of the dusty periods was dominated by the coarse mode, but the coarse mode was similar magnitude to the fine mode during the firework and biomass burning days. The volume concentration of the coarse mode during the dust days increased by a magnitude of more than 2-8 times that derived in the other three aerosol conditions, suggesting that dust is the major contributor of coarse mode particles in Beijing. The single scattering albedo (SSA) values also increased during the pollution episodes. The overall mean SSA at the four wavelengths were 0.865, 0.911, 0.922 and 0.931 in clean, firework display, biomass burning, and dust days in Beijing, respectively. However, in the blue spectral range, the dust aerosols exhibited pronounced absorption.
NASA Astrophysics Data System (ADS)
Morales Rodriguez, Carlos A.; da Rocha, Rosmeri P.; Bombardi, Rodrigo
2010-05-01
This study investigates how the summer thunderstorms developed over the city of São Paulo and if the pollution might affect its development or characteristics during the austral summer (December-January-February-March, DJFM months). A total of 605 days from December 1999 to March 2004 was separated as 241 thunderstorms days (TDs) and 364 non-thunderstorm days (NTDs). The analyses are performed by using hourly measurements of air temperature ( T), web-bulb temperature ( Tw), surface atmospheric pressure ( P), wind velocity and direction, rainfall and thunder and lightning observations collected at the Meteorological Station of the University of São Paulo in conjunction with aerosol measurements obtained by AERONET (Aerosol Robotic Network), and the NCEP-DOE (National Centers for Environmental Prediction Department of Energy) reanalysis and radiosondes. The wind diurnal cycle shows that for TDs the morning flow is from the northwest rotating to the southeast after 16:00 local time (LT) and it remains from the east until the night. For the NTDs, the wind is well characterized by the sea-breeze circulation that in the morning has the wind blowing from the northeast and in the afternoon from the southeast. The TDs show that the air temperature diurnal cycle presents higher amplitude and the maximum temperature of the day is 3.2 °C higher than in NTDs. Another important factor found is the difference between moisture that is higher during TDs. In terms of precipitation, the TDs represent 40% of total of days analyzed and those days are responsible for more than 60% of the total rain accumulation during the summer, for instance 50% of the TDs had more than 15.5 mm day - 1 while the NTDs had 4 mm day - 1 . Moreover, the rainfall distribution shows that TDs have higher rainfall rate intensities and an afternoon precipitation maximum; while in the NTDs there isn't a defined precipitation diurnal cycle. The wind and temperature fields from NCEP reanalysis concur with the local weather station and radiosonde observations. The NCEP composites show that TDs are controlled by synoptic circulation characterized by a pre-frontal situation, with a baroclinic zone situated at southern part of São Paulo. In terms of pollution, this study employed the AERONET data to obtain the main aerosol characteristics in the atmospheric column for both TDs and NTDs. The particle size distribution and particle volume size distribution have similar concentrations for both TDs and NTDs and present a similar fine and coarse mode mean radius. In respect to the atmospheric loading, the aerosol optical depth (AOD) at different frequencies presented closed mean values for both TDs and NTDs that were statistically significant at 95% level. The spectral dependency of those values in conjunction with the Angstrom parameter reveal the higher concentration of the fine mode particles that are more likely to be hygroscopic and from urban areas. In summary, no significant aerosol effect could be found on the development of summer thunderstorms, suggesting the strong synoptic control by the baroclinic forcing for deep convective development.
NASA Astrophysics Data System (ADS)
Wu, X.; Jiang, Y.; Simonsen, S.; van den Broeke, M. R.; Ligtenberg, S.; Kuipers Munneke, P.; van der Wal, W.; Vermeersen, B. L. A.
2017-12-01
Determining present-day mass transport (PDMT) is complicated by the fact that most observations contain signals from both present day ice melting and Glacial Isostatic Adjustment (GIA). Despite decades of progress in geodynamic modeling and new observations, significant uncertainties remain in both. The key to separate present-day ice mass change and signals from GIA is to include data of different physical characteristics. We designed an approach to separate PDMT and GIA signatures by estimating them simultaneously using globally distributed interdisciplinary data with distinct physical information and a dynamically constructed a priori GIA model. We conducted a high-resolution global reappraisal of present-day ice mass balance with focus on Earth's polar regions and its contribution to global sea-level rise using a combination of ICESat, GRACE gravity, surface geodetic velocity data, and an ocean bottom pressure model. Adding ice altimetry supplies critically needed dual data types over the interiors of ice covered regions to enhance separation of PDMT and GIA signatures, and achieve half an order of magnitude expected higher accuracies for GIA and consequently ice mass balance estimates. The global data based approach can adequately address issues of PDMT and GIA induced geocenter motion and long-wavelength signatures important for large areas such as Antarctica and global mean sea level. In conjunction with the dense altimetry data, we solved for PDMT coefficients up to degree and order 180 by using a higher-resolution GRACE data set, and a high-resolution a priori PDMT model that includes detailed geographic boundaries. The high-resolution approach solves the problem of multiple resolutions in various data types, greatly reduces aliased errors from a low-degree truncation, and at the same time, enhances separation of signatures from adjacent regions such as Greenland and Canadian Arctic territories.
Hoang, Hang Thi Thu; Duong, Thi Thuy; Nguyen, Kien Trung; Le, Quynh Thi Phuong; Luu, Minh Thi Nguyet; Trinh, Duc Anh; Le, Anh Hung; Ho, Cuong Tu; Dang, Kim Dinh; Némery, Julien; Orange, Didier; Klein, Judith
2018-01-08
Planktons are a major component of food web structure in aquatic ecosystems. Their distribution and community structure are driven by the combination and interactions between physical, chemical, and biological factors within the environment. In the present study, water quality and the community structure of phytoplankton and zooplankton were monthly investigated from January to December 2015 at 11 sampling sites along the gradient course of the Day River (Red River Delta, northern Vietnam). The study demonstrated that the Day River was eutrophic with the average values of total phosphorus concentration 0.17 mg/L, total nitrogen concentration 1.98 mg/L, and Chl a 54 μg/L. Microscopic plankton analysis showed that phytoplankton comprised 87 species belonging to seven groups in which Chlorophyceae, Bacillariophyceae, and Cyanobacteria accounted for the most important constituents of the river's phytoplankton assemblage. A total 53 zooplankton species belonging to three main groups including Copepoda, Cladocera, and Rotatoria were identified. Plankton biomass values were greatest in rainy season (3002.10-3 cell/L for phytoplankton and 12.573 individuals/m 3 for zooplankton). Using principal correspondence and Pearson correlation analyses, it was found that the Day River was divided into three main site groups based on water quality and characteristics of plankton community. Temperature and nutrients (total phosphorus and total nitrogen) are key factors regulating plankton abundance and distribution in the Day River.
Water Ice Clouds and Dust in the Martian Atmosphere Observed by Mars Climate Sounder
NASA Technical Reports Server (NTRS)
Benson, Jennifer L.; Kass, David; Heavens, Nicholas; Kleinbohl, Armin
2011-01-01
The water ice clouds are primarily controlled by the temperature structure and form at the water condensation level. Clouds in all regions presented show day/night differences. Cloud altitude varies between night and day in the SPH and tropics: (1) NPH water ice opacity is greater at night than day at some seasons (2) The diurnal thermal tide controls the daily variability. (3) Strong day/night changes indicate that the amount of gas in the atmosphere varies significantly. See significant mixtures of dust and ice at the same altitude planet-wide (1) Points to a complex radiative and thermal balance between dust heating (in the visible) and ice heating or cooling in the infrared. Aerosol layering: (1) Early seasons reveal a zonally banded spatial distribution (2) Some localized longitudinal structure of aerosol layers (3) Later seasons show no consistent large scale organization
Distribution of ghrelin-producing cells in the gastrointestinal tract of pigs at different ages.
Vitari, Francesca; Di Giancamillo, Alessia; Deponti, Daniela; Carollo, Valentina; Domeneghini, Cinzia
2012-03-01
Ghrelin is involved in many biological processes, ranging from appetite regulation and the release of growth hormone to the regulation of gastrointestinal motility and secretion processes. Ghrelin expression is not homogenously distributed throughout the gastrointestinal tract; expression is species-specific and can also depend on the animal age. This study was performed to investigate ghrelin immunolocalization in the gastrointestinal tract of pigs at different ages: 1 day (birth), 28 days (weaning), 2 months, 4 months, and 7 months (pre-puberty). Tissue samples were collected along the entire gastrointestinal tract and were examined by immunohistochemistry and double-immunofluorescence. Histometry was performed by counting the number of endocrine ghrelin immunopositive cells in the gastrointestinal mucosa. Ghrelin was found to be present along the swine alimentary canal from the stomach to the caecum. In all regions of the alimentary canal of the animals studied, ghrelin-immunoreactive (IR) cells co-localized with chromogranin-A and were therefore identified as endocrine cells. In the gastric fundus, ghrelin-immunoreactivity was partially detected in co-localization with H-K-adenosine triphosphatase and pepsinogen. Ghrelin-IR endocrine cells were abundant in the oxyntic mucosa but less present in the small intestine and rare in the large intestine. The cell density of the ghrelin-IR endocrine cells was lowest in the oxyntic mucosa of 1-day-old pigs. We can conclude that gastric ghrelin expression is not related merely to age but could also potentially be influenced by food intake.
Changes to the temporal distribution of daily precipitation
NASA Astrophysics Data System (ADS)
Rajah, Kailash; O'Leary, Tess; Turner, Alice; Petrakis, Gabriella; Leonard, Michael; Westra, Seth
2014-12-01
Changes to the temporal distribution of daily precipitation were investigated using a data set of 12,513 land-based stations from the Global Historical Climatology Network. The distribution of precipitation was measured using the Gini index (which describes how uniformly precipitation is distributed throughout a year) and the annual number of wet days. The Mann-Kendall test and a regression analysis were used to assess the direction and rate of change to both indices. Over the period of 1976-2000, East Asia, Central America, and Brazil exhibited a decrease in the number of both wet and light precipitation days, and eastern Europe exhibited a decrease in the number of both wet and moderate precipitation days. In contrast, the U.S., southern South America, western Europe, and Australia exhibited an increase in the number of both wet and light precipitation days. Trends in both directions were field significant at the global scale.
NASA Astrophysics Data System (ADS)
Janská, Veronika; Jiménez-Alfaro, Borja; Chytrý, Milan; Divíšek, Jan; Anenkhonov, Oleg; Korolyuk, Andrey; Lashchinskyi, Nikolai; Culek, Martin
2017-03-01
We modelled the European distribution of vegetation types at the Last Glacial Maximum (LGM) using present-day data from Siberia, a region hypothesized to be a modern analogue of European glacial climate. Distribution models were calibrated with current climate using 6274 vegetation-plot records surveyed in Siberia. Out of 22 initially used vegetation types, good or moderately good models in terms of statistical validation and expert-based evaluation were computed for 18 types, which were then projected to European climate at the LGM. The resulting distributions were generally consistent with reconstructions based on pollen records and dynamic vegetation models. Spatial predictions were most reliable for steppe, forest-steppe, taiga, tundra, fens and bogs in eastern and central Europe, which had LGM climate more similar to present-day Siberia. The models for western and southern Europe, regions with a lower degree of climatic analogy, were only reliable for mires and steppe vegetation, respectively. Modelling LGM vegetation types for the wetter and warmer regions of Europe would therefore require gathering calibration data from outside Siberia. Our approach adds value to the reconstruction of vegetation at the LGM, which is limited by scarcity of pollen and macrofossil data, suggesting where specific habitats could have occurred. Despite the uncertainties of climatic extrapolations and the difficulty of validating the projections for vegetation types, the integration of palaeodistribution modelling with other approaches has a great potential for improving our understanding of biodiversity patterns during the LGM.
[Hospitalization period and nutritional status in hospitalized patients].
Merhi, V A Leandro; de Oliveira, Ma R Marques; Caran, A L; Tristão, T Menuzzo Graupner; Ambo, R Miante; Tanner, M A; Vergna, C Marton
2007-01-01
With the objective of studying the nutritional status and its relationship with hospitalization period, a cross-sectional study was done with patients from a private hospital representing a population with a better socioeconomic condition. The anthropometric data of 267 patients, 46% males and 54% females ranging from 20 to 80 years of age, were assessed on the second day of hospitalization. Hospitalization period associated with nutritional status. The data were analyzed by the software Excel and Sigma Stat, using Fisher's exact test and the chi-square test. The studied population presented a body mass index of 25.9 +/- 5.3 and most patients lost weight during hospitalization. The longest hospitalization periods were found among patients with lung diseases (13 days), some being pre-obese (40%) with a small prevalence of undernutrition (4%). The percentage distribution of nutritional status among the groups according to diagnosis was different (P < 0.01) when assessed by the Fisher's exact test and the percentage distribution in weight variation between men and women was different (P < 0.02) when assessed by the chi-square test. When the population was segmented according to age, the percentage distribution of the nutritional status between > 60 and < or = 60 did not present a difference when assessed by the chi-square test. The results of this study show that the nutritional status in some diseases deserves special attention given the greater risk found in these situations, contributing to a longer hospitalization period.
Magmatism and Dynamic Topography of Libya and Tibesti, North Africa
NASA Astrophysics Data System (ADS)
Ball, P.; White, N. J.; Maclennan, J.; Stuart, F. M.
2016-12-01
In the continents, dynamic topography is difficult to determine because the density structure of the lithosphere is poorly known. It is generally agreed that hot upwelling mantle produces dynamic uplift whilst cold downwelling mantle causes regional subsidence. Calculating asthenospheric potential temperatures from basalts provides one important constraint on dynamic uplift at the present day and in the geologic record. The spatial and temporal distribution of eruptive products together with the compositional variation of lavas allows the origin of continental volcanic events to be interpreted. The Cenozoic Libyan volcanic field is characterized by a series of long wavelength topographic swells that may reflect sub-lithospheric dynamic processes. Admittance analysis of gravity and topographic data as well as seismic tomographic imaging suggest that a low density anomaly sits beneath the lithospheric plate. A new regional basaltic database of 188 XRF and ICP-MS analyses together with 39 40Ar-39Ar dates has been assembled. The Libyan volcanic field has been active from at least 17 Ma until the present day. Inverse modeling of rare earth elemental distributions shows that Libyan basalts were generated by melting of a predominantly anhydrous mixed peridotitic mantle source with an asthenospheric potential temperature of 1400 oC. Our results suggest that the existence and distribution of volcanism is caused by the combination of warm, upwelling asthenospheric mantle and thinner (< 100 km) lithosphere beneath Libya whereby melts may ascend to the surface through metasomatized lithospheric channels.
The resolved star formation history of M51a through successive Bayesian marginalization
NASA Astrophysics Data System (ADS)
Martínez-García, Eric E.; Bruzual, Gustavo; Magris C., Gladis; González-Lópezlira, Rosa A.
2018-02-01
We have obtained the time and space-resolved star formation history (SFH) of M51a (NGC 5194) by fitting Galaxy Evolution Explorer (GALEX), Sloan Digital Sky Survey and near-infrared pixel-by-pixel photometry to a comprehensive library of stellar population synthesis models drawn from the Synthetic Spectral Atlas of Galaxies (SSAG). We fit for each space-resolved element (pixel) an independent model where the SFH is averaged in 137 age bins, each one 100 Myr wide. We used the Bayesian Successive Priors (BSP) algorithm to mitigate the bias in the present-day spatial mass distribution. We test BSP with different prior probability distribution functions (PDFs); this exercise suggests that the best prior PDF is the one concordant with the spatial distribution of the stellar mass as inferred from the near-infrared images. We also demonstrate that varying the implicit prior PDF of the SFH in SSAG does not affect the results. By summing the contributions to the global star formation rate of each pixel, at each age bin, we have assembled the resolved SFH of the whole galaxy. According to these results, the star formation rate of M51a was exponentially increasing for the first 10 Gyr after the big bang, and then turned into an exponentially decreasing function until the present day. Superimposed, we find a main burst of star formation at t ≈ 11.9 Gyr after the big bang.
Stationarity analysis of historical flood series in France and Spain (14th-20th centuries)
NASA Astrophysics Data System (ADS)
Barriendos, M.; Coeur, D.; Lang, M.; Llasat, M. C.; Naulet, R.; Lemaitre, F.; Barrera, A.
Interdisciplinary frameworks for studying natural hazards and their temporal trends have an important potential in data generation for risk assessment, land use planning, and therefore the sustainable management of resources. This paper focuses on the adjustments required because of the wide variety of scientific fields involved in the reconstruction and characterisation of flood events for the past 1000 years. The aim of this paper is to describe various methodological aspects of the study of flood events in their historical dimension, including the critical evaluation of old documentary and instrumental sources, flood-event classification and hydraulic modelling, and homogeneity and quality control tests. Standardized criteria for flood classification have been defined and applied to the Isère and Drac floods in France, from 1600 to 1950, and to the Ter, the Llobregat and the Segre floods, in Spain, from 1300 to 1980. The analysis on the Drac and Isère data series from 1600 to the present day showed that extraordinary and catastrophic floods were not distributed uniformly in time. However, the largest floods (general catastrophic floods) were homogeneously distributed in time within the period 1600-1900. No major flood occurred during the 20th century in these rivers. From 1300 to the present day, no homogeneous behaviour was observed for extraordinary floods in the Spanish rivers. The largest floods were uniformly distributed in time within the period 1300-1900, for the Segre and Ter rivers.
Expression of synapsin I correlates with maturation of the neuromuscular synapse.
Lu, B; Czernik, A J; Popov, S; Wang, T; Poo, M M; Greengard, P
1996-10-01
Synapsins are a family of neuron-specific phosphoproteins that are localized within the presynaptic terminals in adult brain. Previous work has demonstrated that introduction of exogenous synapsins I(a + b) or IIa into Xenopus spinal neurons promoted maturation of the neuromuscular synapse in a nerve-muscle co-culture system. We have now studied the expression of endogenous Xenopus synapsin I during synaptic maturation in vivo and in culture, using a polyclonal antibody raised against Xenopus synapsin I. Immunoprecipitation experiments indicated that synapsin I was not detectable during the early phase of synaptogenesis in vivo, and exhibited a marked increase during the period of synaptic maturation. In contrast, the expression of synaptophysin, another synaptic vesicle protein, was detected at the start of nervous system formation, and remained at a high level thereafter. Similar expression profiles for the two proteins were also observed in immunocytochemical studies of Xenopus spinal neurons in culture: intense staining of synaptophysin was found on the first day, while synapsin I was not detected until after three days in culture. The expression of synapsin I correlated very well with the appearance of a bell-shaped amplitude distribution of spontaneous synaptic currents, a physiological parameter which reflects functional maturation of the neuromuscular synapse. In one-day-old cultures grown in the absence of laminin, an extracellular matrix protein known to be present at the neuromuscular junction, the amplitude distribution of virtually all synapses was skewed towards smaller values. In contrast, when laminin was used as a culture substrate, many synapses exhibited a bell-shaped amplitude distribution. Laminin treatment also induced synapsin I expression in one-day-old cultures. These results suggest that the expression of endogenous synapsin I may regulate maturation at neuromuscular synapses.
Araujo, Gonzalo; Lucey, Anna; Labaja, Jessica; So, Catherine Lee; Snow, Sally; Ponzo, Alessandro
2014-01-01
This study represents the first description of whale sharks, Rhincodon typus, occurring at a provisioning site in Oslob, Cebu, Philippines. Frequent observations of sharks are often difficult, even at tourism sites, giving rise to provisioning activities to attract them. The present study provides repeated longitudinal data at a site where daily provisioning activities took place, and whale sharks were present every day. A total of 158 individual whale sharks were photographically identified between Mar 2012 and Dec 2013, with 129 males (82%), 19 females (12%) and 10 (6%) of undetermined sex. Mean estimated total length was 5.5 m (±1.3 m S.D.). Twenty individuals were measured with laser photogrammetry to validate researchers' estimated sizes, yielding a good correlation (r (2) = 0.83). Fifty-four (34%) individuals were observed being hand-fed by local fishermen (provisioned), through in-water behavioural observations. Maximum likelihood methods were used to model mean residency time of 44.9 days (±20.6 days S.E.) for provisioned R. typus contrasting with 22.4 days (±8.9 days S.E.) for non-provisioned individuals. Propeller scars were observed in 47% of the animals. A mean of 12.7 (±4.3 S.D.) R. typus were present in the survey area daily, with a maximum of 26 individuals (Aug 10 2013) and a minimum of 2 (Dec 6 2012). Twelve (8%) individuals were seen on at least 50% of survey days (n = 621), with a maximum residency of 572 days for one individual (P-396). Twenty four individuals were photographically identified across regional hotsposts, highlighting the species' migratory nature and distribution. Extended residency and differences in lagged identification rates suggest behavioural modification on provisioned individuals, underlying the necessity for proper management of this tourism activity.
Deformation of the total ozone content field in the tropical zone
NASA Technical Reports Server (NTRS)
Vasilyev, Victor I.
1994-01-01
Presented are the ozone investigation results obtained in the tropical zone. Measurements of the total ozone content (TOC) were carried out by the ozonometer M-124. The ozonometer was automated to investigate the ozone intradiurnal variations and to increase precision of the TOC measurements. Obtained results allowed us to follow the effect of tropical cyclones (TC) on the TOC field. Several days before the TC formation the TOC increase is observed in daily mean course compared with the background one. Three types of trend can be singled out in the TOC intradiurnal course: zero, parabolic, quasi-linear. Maximum velocities of a trend are observed some days before the TC formation. Analogous harmonic constituents are mainly presented as spectrum of daily means of ozone, mean and absolute velocities of trend and dispersion as well as spectra of meteorological, hydrometeorological and actinometric values. Revealed is a number of day-to-day ozone variations concerned with large-scale circulations; moisture content in the atmosphere. Obtained are the data about short-period ozone waves (period less than a day). Thin-film silver sensors were used to measure the vertical ozone distribution (VOD). Atmospheric aerosol and VOD measurements were carried out simultaneously, they gave data of the VOD layered structure, where the VOD local minima coincided with the position of aerosol layers' maxima.
On the (Non)Evolution of H I Gas in Galaxies Over Cosmic Time
NASA Astrophysics Data System (ADS)
Prochaska, J. Xavier; Wolfe, Arthur M.
2009-05-01
We present new results on the frequency distribution of projected H I column densities f(N H I , X), total comoving covering fraction, and integrated mass densities ρH I of high-redshift, H I galactic gas from a survey of damped Lyα systems (DLAs) in the Sloan Digital Sky Survey, Data Release 5. For the full sample spanning z = 2.2-5 (738 DLAs), f(N H I , X) is well fitted by a double power law with a break column density Nd = 1021.55±0.04 cm-2 and low/high-end exponents α = -2.00 ± 0.05, - 6.4+1.1 -1.6. The shape of f(N H I , X) is invariant during this redshift interval and also follows the projected surface density distribution of present-day H I disks as inferred from 21 cm observations. We conclude that H I gas has been distributed in a self-similar fashion for the past 12 Gyr. The normalization of f(N H I , X), in contrast, decreases by a factor of 2 during the ≈2 Gyr interval from z = 4-2.2 with coincident decreases in both the total covering fraction and ρH I . At z ≈ 2, these quantities match the present-day values suggesting no evolution during the past ≈10 Gyr. We argue that the evolution at early times is driven by "violent" processes that removes gas from nearly half the galaxies at z ≈ 3 establishing the antecedents of current early-type galaxies. The perceived constancy of ρH I , meanwhile, implies that H I gas is a necessary but insufficient precondition for star formation and that the global star formation rate is driven by the accretion and condensation of fresh gas from the intergalactic medium.
Niyibizi, Christopher; Wang, Sujing; Mi, Zhibao; Robbins, Paul D
2004-06-01
To explore the feasibility of skeletal gene and cell therapies, we transduced murine bone marrow-derived mesenchymal stem cells (MSCs) with a retrovirus carrying the enhanced green fluorescent protein and zeocin-resistance genes prior to transplantation into 2-day-old immunocompetent neonatal mice. Whole-body imaging of the recipient mice at 7 days post-systemic cell injection demonstrated a wide distribution of the cells in vivo. Twenty-five days posttransplantation, most of the infused cells were present in the lung as assessed by examination of the cells cultured from the lungs of the recipient mice. The cells persisted in lung and maintained a high level of gene expression and could be recovered from the recipient mice at 150 days after cell transplantation. A significant number of GFP-positive cells were also present in the bones of the recipient mice at 35 days post-cell transplantation. Recycling of the cells recovered from femurs of the recipient mice at 25 days posttransplantation by repeated injections into different neonatal mice resulted in the isolation of a clone of cells that was detected in bone and cartilage, but not in lung and liver after systemic injection. These data demonstrate that MSCs persist in immunocompetent neonatal mice, maintain a high level of gene expression, and may participate in skeletal growth and development of the recipient animals.
SN 2016esw: a luminous Type II supernova observed within the first day after the explosion
NASA Astrophysics Data System (ADS)
de Jaeger, Thomas; Galbany, Lluis; Gutiérrez, Claudia P.; Filippenko, Alexei V.; Zheng, WeiKang; Brink, Thomas G.; Foley, Ryan J.; Sánchez, Sebastian F.; Channa, Sanyum; de Kouchkovsky, Maxime; Halevi, Goni; Kilpatrick, Charles D.; Kumar, Sahana; Molloy, Jeffrey; Pan, Yen-Chen; Ross, Timothy W.; Shivvers, Isaac; Siebert, Matthew R.; Stahl, Benjamin; Stegman, Samantha; Yunus, Sameen
2018-05-01
We present photometry, spectroscopy, and host-galaxy integral-field spectroscopy of the Type II supernova (SN) 2016esw in CGCG 229-009 from the first day after the explosion up to 120 days. Its light-curve shape is similar to that of a typical SN II; however, SN 2016esw is near the high-luminosity end of the SN II distribution, with a peak of M^maxV=-18.36 mag. The V-band light curve exhibits a long recombination phase for a SN II (similar to the long-lived plateau of SN 2004et). Considering the well-known relation between the luminosity and the plateau decline rate, SN 2016esw should have a V-band slope of ˜2.10 mag (100 days)-1; however, SN 2016esw has a substantially flatter plateau with a slope of 1.01 ± 0.26 mag (100 days)-1, perhaps indicating that interacting Type II supernovae are not useful for cosmology. At 19.5 days post-explosion, the spectrum presents a boxy Hα emission line with flat absorption profiles, suggesting interaction between the ejecta and circumstellar matter. Finally, based on the spectral properties, SN 2016esw shows similarities with the luminous and interacting SN 2007pk at early epochs, particularly in terms of observable line features and their evolution.
Detecting Earth's temporarily-captured natural satellites-Minimoons
NASA Astrophysics Data System (ADS)
Bolin, Bryce; Jedicke, Robert; Granvik, Mikael; Brown, Peter; Howell, Ellen; Nolan, Michael C.; Jenniskens, Peter; Chyba, Monique; Patterson, Geoff; Wainscoat, Richard
2014-10-01
We present a study on the discoverability of temporarily captured orbiters (TCOs) by present day or near-term anticipated ground-based and space-based facilities. TCOs (Granvik, M., Vaubaillon, J., Jedicke, R. [2012]. Icarus 218, 262-277) are potential targets for spacecraft rendezvous or human exploration (Chyba, M., Patterson, G., Picot, G., Granvik, M., Jedicke, R., Vaubaillon, J. [2014]. J. Indust. Manage. Optim. 10, 477-501) and provide an opportunity to study the population of the smallest asteroids in the Solar System. We find that present day ground-based optical surveys such as Pan-STARRS and ATLAS can discover the largest TCOs over years of operation. A targeted survey conducted with the Subaru telescope can discover TCOs in the 0.5-1.0 m diameter size range in about 5 nights of observing. Furthermore, we discuss the application of space-based infrared surveys, such as NEOWISE, and ground-based meteor detection systems such as CAMS, CAMO and ASGARD in discovering TCOs. These systems can detect TCOs but at a uninteresting rate. Finally, we discuss the application of bi-static radar at Arecibo and Green Bank to discover TCOs. Our radar simulations are strongly dependent on the rotation rate distribution of the smallest asteroids but with an optimistic distribution we find that these systems have >80% chance of detecting a >10 cm diameter TCO in about 40 h of operation.
NASA Astrophysics Data System (ADS)
Bouchet, P.; Danziger, I. J.
1993-06-01
We present the infrared (1-20 micron) observations of SN 1987A obtained at ESO La Silla between 29 October 1987 and 27 March 1991 (day 1493); photometry and narrow band CVF spectrophotometry (λ/{DELTA}λ ~ 60) were acquired during that period. The infrared light curves and the spectra are shown and discussed. The spectral energy distribution is dominated by an increasing IR excess after day 530 (beyond 3.5 microns) due to the presence of dust in the envelope which was first discovered by its spectroscopic signature. We show that dust is still present at least until day ~1400, and that the two zone model for the expanding envelope, suggested from the visible spectra obtained at ESO, can account for the observed changes in the near-infrared colours in the period days 530-560. Hydrogen lines, observed in the spectrum from the very beginning, are present until day 1109 (although Brγ is hardly noticeable on the 9 March 1990 spectrum) and we describe the variations of their intensities throughout our monitoring period. Attention is drawn to the presence of CO emission observed until November 1988, and to the evolution of cobalt through the observation of the fine structure line of [Co II] at 10.52 microns. The temporal behaviour of the emission lines due to [Ni I] 3.12 microns and [Si I] + [Fe II] 1.644 microns are also shown.
In search of the Madrean line: biogeography of herpetofauna in the Sky Island region
Don E. Swann; Theresa M. Mau-Crimmins; Eric W. Stitt
2005-01-01
In 1992 Charles H. Lowe proposed a major partition in the distribution of the herpetofauna of southern Arizona and New Mexico between the Madrean Archipelago and the Rocky Mountains along a line that parallels the present-day Interstate 10. We categorized species by elevation and geographic region and used spatial analysis to explore the existence and location of a...
Associated {Upsilon}+{gamma} production at the LHC in the k{sub t}-factorization approach
DOE Office of Scientific and Technical Information (OSTI.GOV)
Baranov, S. P.
In the framework of the k{sub t}-factorization approach, the photon-associated production of {Upsilon} mesons at the present-day LHC conditions is studied. The differential cross sections and polarization parameters are calculated in the ''helicity'' and Collins-Soper systems. Special attention is paid to the effect of experimental cuts that can dramatically change the visible lepton angular distributions.
Resolving runaway electron distributions in space, time, and energy
NASA Astrophysics Data System (ADS)
Paz-Soldan, C.; Cooper, C. M.; Aleynikov, P.; Eidietis, N. W.; Lvovskiy, A.; Pace, D. C.; Brennan, D. P.; Hollmann, E. M.; Liu, C.; Moyer, R. A.; Shiraki, D.
2018-05-01
Areas of agreement and disagreement with present-day models of runaway electron (RE) evolution are revealed by measuring MeV-level bremsstrahlung radiation from runaway electrons (REs) with a pinhole camera. Spatially resolved measurements localize the RE beam, reveal energy-dependent RE transport, and can be used to perform full two-dimensional (energy and pitch-angle) inversions of the RE phase-space distribution. Energy-resolved measurements find qualitative agreement with modeling on the role of collisional and synchrotron damping in modifying the RE distribution shape. Measurements are consistent with predictions of phase-space attractors that accumulate REs, with non-monotonic features observed in the distribution. Temporally resolved measurements find qualitative agreement with modeling on the impact of collisional and synchrotron damping in varying the RE growth and decay rate. Anomalous RE loss is observed and found to be largest at low energy. Possible roles for kinetic instability or spatial transport to resolve these anomalies are discussed.
Increase in body temperature during migraine attacks.
Ordás, Carlos M; Cuadrado, María L; Rodríguez-Cambrón, Ana B; Casas-Limón, Javier; del Prado, Náyade; Porta-Etessam, Jesús
2013-08-01
Intermittent fever has been occasionally related to migraine, either as a migraine equivalent or as a migraine accompaniment. We present a case of recurrent increase in body temperature consistently associated with migraine headaches. A 15-year-old girl reported a 3-year lasting history of migraine without aura, with a feeling of warmth occurring in each episode. Ancillary tests did not show any evidence of secondary headaches or any systemic disease. A 2-month headache diary was obtained, with daily records of headache intensity (0, no headache; 1, mild pain; 2, moderate pain; 3, severe pain) and simultaneous measurements of axillary temperature. Both parameters were registered in the evening, at 6:00 pm every day. The distribution of headache intensity and body temperature as well as the relationship between both variables over time were analyzed with nonparametric tests. The number of days without pain was 28 (45.2%); a mild headache was present on 13 days (21%), a moderate headache on 15 days (24.2%), and a severe headache on 6 days (9.7%). Headache days were associated with higher body temperature than headache-free days (median values: 37.3°C vs 36.6°C; Mann-Whitney U-test, P < 0.001). Moreover, a positive correlation was found between headache intensity and body temperature (Spearman's rho coefficient: 0.83, P < 0.001). Recurrent increase in body temperature may be another manifestation of the complex clinical spectrum of migraine. This symptom is probably related to hypothalamic involvement. Wiley Periodicals, Inc.
Ginger, Luke; Cage, Marcy; David, Kyle T.; Chakrabarty, Prosanta; Johnston, Mark; Matamoros, Wilfredo A.
2017-01-01
The distributions of many Northern Hemisphere organisms have been influenced by fluctuations in sea level and climatic conditions during Pleistocene interglacial periods. These cycles are associated with range contraction and refugia for northern-distributed organisms as a response to glaciers. However, lower sea levels in the tropics and sub-tropics created available habitat for expansion of the ranges of freshwater organisms. The goal of this study was to use ecological niche modeling to test the hypothesis of north to south range expansion of Vieja maculicauda associated with Pleistocene glacial cycles. Understanding the biogeography of this widespread species may help us better understand the geology and interconnectivity of Central American freshwaters. Occurrence data for V. maculicauda was based on georeferencing of all museum records of specimens recovered from FishNet2. General patterns of phylogeographic structure were assessed with mtDNA. Present day niche models were generated and subsequently projected onto paleoclimatic maps of the region during the Last Interglacial, Last Glacial Maximum, and mid-Holocene. Phylogenetic analysis of mtDNA sequence data showed no phylogeographic structure throughout the range of this widespread species. Present day niche models were congruent with the observed distribution of V. maculicauda in Central America. Results showed a lack of suitable freshwater habitat in northern Central America and Mexico during the Last Interglacial, with greatest range expansion during the Last Glacial Maximum and mid-Holocene. Results support the hypothesis of a north to south range expansion of V. maculicauda associated with glacial cycles. The wide distribution of this species compared to other closely related cichlids indicates the latter did not respond to the degree of V. maculicauda in expansion of their distributions. Future work aimed at comparisons with other species and modeling of future climatic scenarios will be a fruitful area of investigation. PMID:28558052
Jason 1 Investigation: Altimetric Studies of Ocean Tidal Dynamics
NASA Technical Reports Server (NTRS)
Egbert, Gary D.
2004-01-01
Two papers on tidal dissipation were completed and published. The first of these extended our earlier work, which focused on the dominant M2 constituent, to include 7 additional constituents. In addition to confirming a total deep water dissipation total very close to 1 TW, this study demonstrated significant differences in the distribution of dissipation between diurnal and semi-diurnal constituents. The second paper involved an extensive modeling study of tides in the present day and the last glacial maximum. In this study we showed that accuracy of tidal solutions for the present day Ocean were significantly improved by including a parameterization of internal tide drag over rough topography in the deep ocean. It was also demonstrated that a complete self-consistent treatment of Ocean self attraction and tidal loading was required for accurate solutions.
NASA Astrophysics Data System (ADS)
Kodaira, Satoshi; Kawashima, Hajime; Kurano, Mieko; Uchihori, Yukio; Nikolaev, Igor; Ambrozova, Iva; Kitamura, Hisashi; Kartsev, Ivan; Tolochek, Raisa; Shurshakov, Vyacheslav
The measurement of dose equivalent and effective dose during manned space missions on the International Space Station (ISS) is important for evaluating the risk to astronaut health and safety when exposed to space radiation. The dosimetric quantities are constantly changing and strongly depend on the level of solar activity and the various spacecraft- and orbit-dependent parameters such as the shielding distribution in the ISS module, location of the spacecraft within its orbit relative to the Earth, the attitude (orientation) and altitude. Consequently, the continuous monitoring of dosimetric quantities is required to record and evaluate the personal radiation dose for crew members during spaceflight. The dose distributions in the phantom body and on its surface give crucial information to estimate the dose equivalent in the human body and effective dose in manned space mission. We have measured the absorbed dose and dose equivalent rates using passive dosimeters installed in the spherical phantom in Japanese Experiment Module (“KIBO”) of the ISS in the framework of Matroshka-R space experiment. The exposure duration was 114 days from May 21 to September 12, 2012. The phantom consists of tissue-equivalent material covered with a poncho jacket with 32 pockets on its surface and 20 container rods inside of the phantom. The phantom diameter is 35 cm and the mass is 32 kg. The passive dosimeters consisted of a combination of luminescent detectors of Al _{2}O _{3};C OSL and CaSO _{4}:Dy TLD and CR-39 plastic nuclear track detectors. As one of preliminary results, the dose distribution on the phantom surface measured with OSL detectors installed in the jacket pockets is found to be ranging from 340 muGy/day to 260 muGy/day. In this talk, we will present the detail dose distributions, and variations of LET spectra and quality factor obtained outside and inside of the spherical phantom installed in the ISS-KIBO.
Norouzpour Deilami, Kiumars; Daryani, Ahmad; Ahmadpour, Ehsan; Sharif, Mehdi; Dadimoghaddam, Yousef; Sarvi, Shahabeddin; Alizadeh, Ahad
2014-12-01
Toxoplasmosis, responsible for ocular impairment, is caused by Toxoplasma gondii. We investigated the effect of Toxoplasma excretory-secretory antigens (ESA) on parasite load and distribution in the eye tissue of a murine model. Case and control groups were immunized with ESA and PBS, respectively. Two weeks after the second immunization, the mice were challenged intraperitoneally with virulent RH strain of Toxoplasma; eye tissue samples of both groups were collected daily (days 1, 2, 3, and the last day before death). Parasite load was determined using real-time quantitative PCR targeted at the B1 gene. Compared to the control group, infected mice that received ESA vaccine presented a considerable decrease in parasite load in the eye tissue, demonstrating the effect of ESA on parasite load and distribution. Diminution of parasite load in mouse eye tissue indicated that ESA might help control disease-related complications and could be a valuable immunization candidate against ocular toxoplasmosis. Copyright © 2014 Elsevier Ltd. All rights reserved.
Parallel discrete event simulation using shared memory
NASA Technical Reports Server (NTRS)
Reed, Daniel A.; Malony, Allen D.; Mccredie, Bradley D.
1988-01-01
With traditional event-list techniques, evaluating a detailed discrete-event simulation-model can often require hours or even days of computation time. By eliminating the event list and maintaining only sufficient synchronization to ensure causality, parallel simulation can potentially provide speedups that are linear in the numbers of processors. A set of shared-memory experiments, using the Chandy-Misra distributed-simulation algorithm, to simulate networks of queues is presented. Parameters of the study include queueing network topology and routing probabilities, number of processors, and assignment of network nodes to processors. These experiments show that Chandy-Misra distributed simulation is a questionable alternative to sequential-simulation of most queueing network models.
NASA Astrophysics Data System (ADS)
Kovilakam, Mahesh; Mahajan, Salil; Saravanan, R.; Chang, Ping
2017-10-01
We alleviate the bias in the tropospheric vertical distribution of black carbon aerosols (BC) in the Community Atmosphere Model (CAM4) using the Cloud-Aerosol and Infrared Pathfinder Satellite Observations (CALIPSO)-derived vertical profiles. A suite of sensitivity experiments are conducted with 1x, 5x, and 10x the present-day model estimated BC concentration climatology, with (corrected, CC) and without (uncorrected, UC) CALIPSO-corrected BC vertical distribution. The globally averaged top of the atmosphere radiative flux perturbation of CC experiments is ˜8-50% smaller compared to uncorrected (UC) BC experiments largely due to an increase in low-level clouds. The global average surface temperature increases, the global average precipitation decreases, and the ITCZ moves northward with the increase in BC radiative forcing, irrespective of the vertical distribution of BC. Further, tropical expansion metrics for the poleward extent of the Northern Hemisphere Hadley cell (HC) indicate that simulated HC expansion is not sensitive to existing model biases in BC vertical distribution.
Gómez Lutz, M C; Kehr, A I; Fernández, L A
2015-06-01
The spatial distribution and temporal variation of 11 species of Tropisternus were analyzed in two permanent ponds located in the province of Corrientes, Argentina. Samples were collected every 15 days, between October 2010 and March 2011. The species recorded were Tropisternus collaris (Fabricius), Tropisternus ovalis Castelnau, Tropisternus laevis (Sturm), Tropisternus lateralis limbatus (Brullé), Tropisternus longispina Fernández & Bachmann, Tropisternus carinispina Orchymont, Tropisternus bourmeisteri Fernández & Bachmann, Tropisternus apicipalpis (Chevrolat), Tropisternus dilatatus Bruch, Tropisternus obesus Bruch, and Tropisternus ignoratus Knisch. The first four were present in higher proportions than the remaining during most of the study period. The spatial distribution of individuals was mostly related to the homogeneity or heterogeneity of the ecosystem in relation to microhabitats with aquatic vegetation: In ponds with different microhabitats, individuals were mainly aggregated, whereas in ponds with homogenous features, individuals were randomly distributed. However, when species were analyzed individually, the spatial distribution and the use of microhabitat by each species were different with respect to preference and behavior.
Mantle convection and the distribution of geochemical reservoirs in the silicate shell of the Earth
NASA Astrophysics Data System (ADS)
Walzer, Uwe; Hendel, Roland
2010-05-01
We present a dynamic 3-D spherical-shell model of mantle convection and the evolution of the chemical reservoirs of the Earth`s silicate shell. Chemical differentiation, convection, stirring and thermal evolution constitute an inseparable dynamic system. Our model is based on the solution of the balance equations of mass, momentum, energy, angular momentum, and four sums of the number of atoms of the pairs 238U-206Pb, 235U-207Pb, 232Th-208Pb, and 40K-40Ar. Similar to the present model, the continental crust of the real Earth was not produced entirely at the start of the evolution but developed episodically in batches [1-7]. The details of the continental distribution of the model are largely stochastic, but the spectral properties are quite similar to the present real Earth. The calculated Figures reveal that the modeled present-day mantle has no chemical stratification but we find a marble-cake structure. If we compare the observational results of the present-day proportion of depleted MORB mantle with the model then we find a similar order of magnitude. The MORB source dominates under the lithosphere. In our model, there are nowhere pure unblended reservoirs in the mantle. It is, however, remarkable that, in spite of 4500 Ma of solid-state mantle convection, certain strong concentrations of distributed chemical reservoirs continue to persist in certain volumes, although without sharp abundance boundaries. We deal with the question of predictable and stochastic portions of the phenomena. Although the convective flow patterns and the chemical differentiation of oceanic plateaus are coupled, the evolution of time-dependent Rayleigh number, Rat , is relatively well predictable and the stochastic parts of the Rat(t)-curves are small. Regarding the juvenile growth rates of the total mass of the continents, predictions are possible only in the first epoch of the evolution. Later on, the distribution of the continental-growth episodes is increasingly stochastic. Independently of the varying individual runs, our model shows that the total mass of the present-day continents is not generated in a single process at the beginning of the thermal evolution of the Earth but in episodically distributed processes in the course of geological time. This is in accord with observation. Finally, we present results regarding the numerical method, implementation, scalability and performance. References [1] Condie, K. C., Episodie continental growth models: Afterthoughts and extensions, Tectonophysics, 322 (2000), 153-162. [2] Davidson, J. P. and Arculus, R. J., The significance of Phanerozoic arc magmatism in generating continental crust, in Evolution and Differentiation of the Continental Crust, edited by M. Brown and T. Rushmer (2006), 135-172, Cambridge Univ. Press, Cambridge, UK. [3] Hofmann, A. W., Sampling mantle heterogeneity through oceanic basalts: Isotopes and trace elements, in Treatise on Geochemistry, Vol. 2: The Mantle and the Core, edited by R. W. Carlson (2003), 61-101, Elsevier, Amsterdam. [4] Rollinson, H., Crustal generation in the Archean, in Evolution and Differentiation of the Continental Crust, edited by M. Brown and T. Rushmer (2006), 173-230, Cambridge Univ. Press, Cambridge, UK: [5] Taylor, S. R. and McLennan, S. M., Planetary Crusts. Their Composition, Origin and Evolution. (2009), 1-378, Cambridge Univ. Press, Cambridge, UK. [6] Walzer, U. and Hendel, R., Mantle convection and evolution with growing continents. J. Geophys. Res. 113 (2008), B09405, doi: 10.1029/2007JB005459 [7] http://www.igw.uni-jena.de/geodyn
Application of a nuclear microprobe to the study of calcified tissues
NASA Astrophysics Data System (ADS)
Coote, Graeme E.; Vickridge, Ian C.
1988-03-01
The mineral fraction of calcified tissue is largely calcium hydroxyapatite (bones and teeth) or calcium carbonate (shells and fish otoliths). Apatite has such a strong affinity for fluoride ions that the F/Ca ratio can vary markedly with position in a bone or tooth, depending on the amount of fluoride present at the time of calcification or partial recrystallization. New biological information can be obtained by introducing extra fluoride into the diet of an animal and using a microprobe later to scan sections of bones or teeth. In suitable burial sites extra fluoride is introduced after death, and the new distribution may have applications in forensic science and archaeology. Fish otoliths are also of interest since a new carbonate layer is formed each day and the distribution of trace elements may record some aspects of the fish's life history. Results from the following studies are presented: fluorine distributions in the teeth of sheep which ingested extra fluoride for known periods; distributions of calcium and fluorine in femurs of rats which drank water high in fluoride for periods from 2 to 15 weeks; calcium and fluorine distributions in artificially-prepared lesions in tooth enamel; diffusion profiles in archaeological human teeth and animal bones; patterns in the strontium/calcium ratio in sectioned otoliths of several species of fish.
Withdrawal times of oxytetracycline and tylosin in eggs of laying hens after oral administration.
Muñoz, Rubén; Cornejo, Javiera; Maddaleno, Aldo; Araya-Jordán, Carolina; Iragüen, Daniela; Pizarro, Nicolás; San Martín, Betty
2014-06-01
Antimicrobials administered to laying hens may be distributed into egg white or yolk, indicating the importance of evaluating withdrawal times (WDTs) of the pharmaceutical formulations. In the present study, oxytetracycline and tylosin's WDTs were estimated. The concentration and depletion of these molecules in eggs were linked to their pharmacokinetic and physicochemical properties. Twenty-seven Leghorn hens were used: 12 treated with oxytetracycline, 12 treated with tylosin, and 3 remained as an untreated control group. After completion of therapies, eggs were collected daily and drug concentrations in egg white and yolk were assessed. The yolk was used as the target tissue to evaluate the WDT; the results were 9 and 3 days for oxytetracycline and tylosin, respectively. In particular, oxytetracycline has a good oral bioavailability, a moderate apparent volume of distribution, a molecular weight of 460 g/mol, and is lightly liposoluble. Tylosin, a hydrosoluble compound, with a molecular weight of 916 g/mol, has a low oral bioavailability and a low apparent volume of distribution, too. Present results suggest that the WDTs of the studied antimicrobials are strongly influenced by their oral bioavailability, the distribution, and the molecular weight and solubility, and that these properties also influence the distribution between the egg yolk and white.
Piras, Bryan A; Drury, Jason E; Morton, Christopher L; Spence, Yunyu; Lockey, Timothy D; Nathwani, Amit C; Davidoff, Andrew M; Meagher, Michael M
2016-01-01
With clinical trials ongoing, efficient clinical production of adeno-associated virus (AAV) to treat large numbers of patients remains a challenge. We compared distribution of AAV8 packaged with Factor VIII (FVIII) in cell culture media and lysates on days 3, 5, 6, and 7 post-transfection and found increasing viral production through day 6, with the proportion of viral particles in the media increasing from 76% at day 3 to 94% by day 7. Compared to FVIII, AAV8 packaged with Factor IX and Protective Protein/Cathepsin A vectors demonstrated a greater shift from lysate towards media from day 3 to 6, implying that particle distribution is dependent on recombinant vector. Larger-scale productions showed that the ratio of full-to-empty AAV particles is similar in media and lysate, and that AAV harvested on day 6 post-transfection provides equivalent function in mice compared to AAV harvested on day 3. This demonstrates that AAV8 production can be optimized by prolonging the duration of culture post-transfection, and simplified by allowing harvest of media only, with disposal of cells that contain 10% or less of total vector yield. Additionally, the difference in particle distribution with different expression cassettes implies a recombinant vector-dependent processing mechanism which should be taken into account during process development. PMID:27069949
A comparative analysis of massed vs. distributed practice on basic math fact fluency growth rates.
Schutte, Greg M; Duhon, Gary J; Solomon, Benjamin G; Poncy, Brian C; Moore, Kathryn; Story, Bailey
2015-04-01
To best remediate academic deficiencies, educators need to not only identify empirically validated interventions but also be able to apply instructional modifications that result in more efficient student learning. The current study compared the effect of massed and distributed practice with an explicit timing intervention to evaluate the extent to which these modifications lead to increased math fact fluency on basic addition problems. Forty-eight third-grade students were placed into one of three groups with each of the groups completing four 1-min math explicit timing procedures each day across 19 days. Group one completed all four 1-min timings consecutively; group two completed two back-to-back 1-min timings in the morning and two back-to-back 1-min timings in the afternoon, and group three completed one, 1-min independent timing four times distributed across the day. Growth curve modeling was used to examine the progress throughout the course of the study. Results suggested that students in the distributed practice conditions, both four times per day and two times per day, showed significantly higher fluency growth rates than those practicing only once per day in a massed format. These results indicate that combining distributed practice with explicit timing procedures is a useful modification that enhances student learning without the addition of extra instructional time when targeting math fact fluency. Copyright © 2015 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.
Characterization of quantum well structures using a photocathode electron microscope
NASA Technical Reports Server (NTRS)
Spencer, Michael G.; Scott, Craig J.
1989-01-01
Present day integrated circuits pose a challenge to conventional electronic and mechanical test methods. Feature sizes in the submicron and nanometric regime require radical approaches in order to facilitate electrical contact to circuits and devices being tested. In addition, microwave operating frequencies require careful attention to distributed effects when considering the electrical signal paths within and external to the device under test. An alternative testing approach which combines the best of electrical and optical time domain testing is presented, namely photocathode electron microscope quantitative voltage contrast (PEMQVC).
Area and Carbon Content of Sphagnum Since Last Glacial Maximum
Gajewski, K. [University of Ottawa, Ottawa, Ontario (Canada); Viau, A. [University of Ottawa, Ottawa, Ontario (Canada); Sawada, M. [University of Ottawa, Ottawa, Ontario (Canada); Atkinson, D. [University of Ottawa, Ottawa, Ontario (Canada); Wilson, S. [University of Ottawa, Ottawa, Ontario (Canada)
2002-01-01
The distribution and abundance of Sphagnum spores in North America and Eurasia are mapped for the past 21ka, as described in Gajewski et al. (2002). In summary, spore data were taken from existing pollen data bases, as were radiocarbon chronologies. The abundance of Sphagnum spores was mapped at 2000-year intervals beginning 21000 years BP (before present). The present-day distribution of abundant Sphagnum spores corresponds closely to areas with peatland development, with maximum Sphagnum abundance between 630 and 1300 mm annual precipitation and between -2° and 60°C mean annual air temperature. Carbon content of peatlands was generated from estimated peatland area, calculated values of peat thickness, and specified values of bulk density (112 × 103 g m-3) and fraction of carbon (51.7%).
Espisodic detachment of Martian crustal magnetic fields leading to bulk atmospheric plasma escape
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brain, D A; Baker, A H; Briggs, J
2009-06-02
We present an analysis of magnetic field and suprathermal electron measurements from the Mars Global Surveyor (MGS) spacecraft that reveals isolated magnetic structures filled with Martian atmospheric plasma located downstream from strong crustal magnetic fields with respect to the flowing solar wind. The structures are characterized by magnetic field enhancements and rotations characteristic of magnetic flux ropes, and characteristic ionospheric electron energy distributions with angular distributions distinct from surrounding regions. These observations indicate that significant amounts of atmosphere are intermittently being carried away from Mars by a bulk removal process: the top portions of crustal field loops are stretched throughmore » interaction with the solar wind and detach via magnetic reconnection. This process occurs frequently and may account for as much as 10% of the total present-day ion escape from Mars.« less
Parravano, Antonio; Noguera, José A.; Hermida, Paula; Tena-Sánchez, Jordi
2015-01-01
Models of social influence have explored the dynamics of social contagion, imitation, and diffusion of different types of traits, opinions, and conducts. However, few behavioral data indicating social influence dynamics have been obtained from direct observation in “natural” social contexts. The present research provides that kind of evidence in the case of the public expression of political preferences in the city of Barcelona, where thousands of citizens supporting the secession of Catalonia from Spain have placed a Catalan flag in their balconies and windows. Here we present two different studies. 1) During July 2013 we registered the number of flags in 26% of the electoral districts in the city of Barcelona. We find that there is a large dispersion in the density of flags in districts with similar density of pro-independence voters. However, by comparing the moving average to the global mean we find that the density of flags tends to be fostered in electoral districts where there is a clear majority of pro-independence vote, while it is inhibited in the opposite cases. We also show that the distribution of flags in the observed districts deviates significantly from that of an equivalent random distribution. 2) During 17 days around Catalonia’s 2013 national holiday we observed the position at balcony resolution of the flags displayed in the facades of a sub-sample of 82 blocks. We compare the ‘clustering index’ of flags on the facades observed each day to thousands of equivalent random distributions. Again we provide evidence that successive hangings of flags are not independent events but that a local influence mechanism is favoring their clustering. We also find that except for the national holiday day the density of flags tends to be fostered in facades located in electoral districts where there is a clear majority of pro-independence vote. PMID:25961562
NASA Astrophysics Data System (ADS)
Cuyckens, G. A. E.; Christie, D. A.; Domic, A. I.; Malizia, L. R.; Renison, D.
2016-02-01
Climate change is becoming an increasing threat to biodiversity. Consequently, methods for delineation, establishment and management of protected areas must consider the species' future distribution in response to future climate conditions. Biodiversity in high altitude semiarid regions may be particularly threatened by future climate change. In this study we assess the main environmental variables that best explain present day presence of the world's highest elevation woodlands in the South American Altiplano, and model how climate change may affect the future distribution of this unique ecosystem under different climate change scenarios. These woodlands are dominated by Polylepis tarapacana (Rosaceae), a species that forms unique biological communities with important conservation value. Our results indicate that five environmental variables are responsible for 91% and 90.3% of the present and future P. tarapacana distribution models respectively, and suggest that at the end of the 21st century, there will be a significant reduction (56%) in the potential habitat for this species due to more arid conditions. Since it is predicted that P. tarapacana's potential distribution will be severely reduced in the future, we propose a new network of national protected areas across this species distribution range in order to insure the future conservation of this unique ecosystem. Based on an extensive literature review we identify research topics and recommendations for on-ground conservation and management of P. tarapacana woodlands.
The global distribution of Martian permafrost
NASA Technical Reports Server (NTRS)
Paige, David A.
1991-01-01
Accurately determining the present global distribution of Martian ground ice will be an important step towards understanding the evolution of the Martian surface and atmosphere, and could greatly facilitate human and robotic exploration of the planet. The quantitative Mars permafrost studies demonstrated the potential importance of a number of factors determining the past and present distribution of subsurface ice on Mars, but have not considered the issue of regional variability. To consider the distribution of Mars permafrost in greater detail a new thermal model was developed that can calculate Martian surface and subsurface temperatures as a function of time-of-day and season. The results indicate that the distribution of Martian permafrost is highly sensitive to the bulk thermal properties of the overlying soil. Viking IRTM observations of diurnal surface temperature variations show that the bulk thermal properties of midlatitude surface materials exhibit a high degree of regional inhomogeneity. In general, the results show that the global distribution of permafrost is at least as sensitive to the thermal properties of the overlying surface material as it is to variations in surface isolation due to large scale variations in Mars' orbital and axial elements. In particular, they imply that subsurface ice may exist just a few centimeters below the surface in regions of low thermal inertia and high albedo, which are widespread at latitudes ranging from the equator to +60 degrees latitude.
Sandler, A D; Maher, J W; Weinstock, J V; Schmidt, C D; Schlegel, J F; Jew, J Y; Williams, T H
1993-10-01
The specific functions of the numerous substance P (SP) nerve fibers present within the gastrointestinal tract are not clearly defined. This study examines both functional aspects and distribution of immunoreactive SP (IR-SP) in the canine gastroesophageal junctional (GEJ) region. Lower esophageal sphincter pressure (LESP), mean arterial pressure (MAP), pulse rate (PR), and respiratory rate (RR) were monitored before and after topical application of 2 ml capsaicin (8-methyl-N-vanillyl-6-nonenamide) to the distal esophageal mucosa of anesthetized dogs. Animals then underwent a capsaicin desensitization protocol over a 12-day period. The responses of monitored variables were compared on Day 1 and Day 12 of repetitive capsaicin application. Immunohistochemistry and radioimmunoassay (RIA) were performed on GEJ segments to study the distribution and content of IR-SP in both control (untreated) and capsaicin-treated dogs. The IR-SP was extracted from tissue for RIA and analysis by reverse-phase high-performance liquid chromatography (HPLC). On Day 1, a 2-ml capsaicin application stimulated increases in LESP (44.3 +/- 7.8 cm H2O; P < 0.05), MAP (48 +/- 8.7 mm Hg; P < 0.05), PR (52.6 +/- 20.5 beats/min; P < 0.05), and RR (26.3 +/- 15.6 breaths/min; P > 0.2). No response was observed on Day 12 of treatment. This was accompanied by a 43.3% decrease of IR-SP content in the mucosa of the distal esophagus of desensitized animals. Capsaicin applied at greater concentrations on Day 12 stimulated a return of responses (P < 0.05). Ganglia, cell bodies, nerve fascicles, and neurites stained positively for IR-SP. IR-SP content was markedly higher in esophageal mucosa than in gastric mucosa (P < 0.05). The authenticity of the IR-SP molecule was confirmed by elution time on HPLC. In conclusion, repetitive capsaicin application induced a state of homologous desensitization which was accompanied by a partial depletion of mucosal SP. The GEJ region contains a high SP content with a broad neural distribution. These findings are consistent with the hypothesis that SP may act as a neurotransmitter for chemonociceptive stimuli in the canine distal esophagus.
[Quantitative study of diesel/CNG buses exhaust particulate size distribution in a road tunnel].
Zhu, Chun; Zhang, Xu
2010-10-01
Vehicle emission is one of main sources of fine/ultra-fine particles in many cities. This study firstly presents daily mean particle size distributions of mixed diesel/CNG buses traffic flow by 4 days consecutive real world measurement in an Australia road tunnel. Emission factors (EFs) of particle size distribution of diesel buses and CNG buses are obtained by MLR methods, particle distributions of diesel buses and CNG buses are observed as single accumulation mode and nuclei-mode separately. Particle size distributions of mixed traffic flow are decomposed by two log-normal fitting curves for each 30 min interval mean scans, the degrees of fitting between combined fitting curves and corresponding in-situ scans for totally 90 fitting scans are from 0.972 to 0.998. Finally particle size distributions of diesel buses and CNG buses are quantified by statistical whisker-box charts. For log-normal particle size distribution of diesel buses, accumulation mode diameters are 74.5-86.5 nm, geometric standard deviations are 1.88-2.05. As to log-normal particle size distribution of CNG buses, nuclei-mode diameters are 19.9-22.9 nm, geometric standard deviations are 1.27-1.3.
Daily Mean Temperature Affects Urolithiasis Presentation in Seoul: a Time-series Analysis.
Lee, SeoYeon; Kim, Min-Su; Kim, Jung Hoon; Kwon, Jong Kyou; Chi, Byung Hoon; Kim, Jin Wook; Chang, In Ho
2016-05-01
This study aimed to investigate the overall cumulative exposure-response and the lag response relationships between daily temperature and urolithiasis presentation in Seoul. Using a time-series design and distributing lag nonlinear methods, we estimated the relative risk (RR) of urolithiasis presentation associated with mean daily temperature, including the cumulative RR for a 20 days period, and RR for individual daily lag through 20 days. We analyzed data from 14,518 patients of 4 hospitals emergency department who sought medical evaluation or treatment of urolithiasis from 2005-2013 in Seoul. RR was estimated according to sex and age. Associations between mean daily temperature and urolithiasis presentation were not monotonic. Furthermore, there was variation in the exposure-response curve shapes and the strength of association at different temperatures, although in most cases RRs increased for temperatures above the 13°C reference value. The RRs for urolothiasis at 29°C vs. 13°C were 2.54 in all patients (95% confidence interval [CI]: 1.67-3.87), 2.59 in male (95% CI, 1.56-4.32), 2.42 in female (95% CI, 1.15-5.07), 3.83 in male less than 40 years old (95% CI, 1.78-8.26), and 2.47 in male between 40 and 60 years old (95% CI, 1.15-5.34). Consistent trends of increasing RR of urolithiasis presentation were observed within 5 days of high temperatures across all groups. Urolithiasis presentation increased with high temperature with higher daily mean temperatures, with the strongest associations estimated for lags of only a few days, in Seoul, a metropolitan city in Korea.
NASA Astrophysics Data System (ADS)
Scafetta, Nicola; Mazzarella, Adriano
2018-01-01
Mazzarella and Scafetta (2016) showed that the seismic activity recorded at the Bunker-East (BKE) Vesuvian station from 1999 to 2014 suggests a higher nocturnal seismic activity. However, this station is located at about 50 m from the main road to the volcano's crater and since 2009 its seismograms also record a significant diurnal cultural noise due mostly to tourist tours to Mt. Vesuvius. Herein, we investigate whether the different seismic frequency between day and night times could be an artifact of the peculiar cultural noise that affects this station mostly from 9:00 am to 5:00 pm from spring to fall. This time-distributed cultural noise should evidently reduce the possibility to detect low magnitude earthquakes during those hours but not high magnitude events. Using hourly distributions referring to different magnitude thresholds from M = 0.2 to M = 2.0, the Gutenberg-Richter magnitude-frequency diagram applied to the day and night-time sub-catalogs and Montecarlo statistical modeling, we demonstrate that the day-night asymmetry persists despite an evident disruption induced by cultural noise during day-hours. In particular, for the period 1999-2017, and for earthquakes with M ≥ 2 we found a Gutenberg-Richter exponent b = 1.66 ± 0.07 for the night-time events and b = 2.06 ± 0.07 for day-time events. Moreover, we repeat the analysis also for an older BKE catalog covering the period from 1992 to 2000 when cultural noise was not present. The analysis confirms a higher seismic nocturnal activity that is also characterized by a smaller Gutenberg-Richter exponent b for M ≥ 2 earthquakes relative to the day-time activity. Thus, the found night-day seismic asymmetric behavior is likely due to a real physical feature affecting Mt. Vesuvius.
Code of Federal Regulations, 2010 CFR
2010-04-01
... ADMINISTRATION General Rules Application of Internal Revenue Laws § 301.9100-20T Election to treat certain distributions as made on the last day of the taxable year. (a) In general. Section 233(b) of the Revenue Act of... 26 Internal Revenue 18 2010-04-01 2010-04-01 false Election to treat certain distributions as made...
Conlon, Kathryn; Monaghan, Andrew; Hayden, Mary; Wilhelmi, Olga
2016-01-01
Extreme heat events in the United States are projected to become more frequent and intense as a result of climate change. We investigated the individual and combined effects of land use and warming on the spatial and temporal distribution of daily minimum temperature (Tmin) and daily maximum heat index (HImax) during summer in Houston, Texas. Present-day (2010) and near-future (2040) parcel-level land use scenarios were embedded within 1-km resolution land surface model (LSM) simulations. For each land use scenario, LSM simulations were conducted for climatic scenarios representative of both the present-day and near-future periods. LSM simulations assuming present-day climate but 2040 land use patterns led to spatially heterogeneous temperature changes characterized by warmer conditions over most areas, with summer average increases of up to 1.5°C (Tmin) and 7.3°C (HImax) in some newly developed suburban areas compared to simulations using 2010 land use patterns. LSM simulations assuming present-day land use but a 1°C temperature increase above the urban canopy (consistent with warming projections for 2040) yielded more spatially homogeneous metropolitan-wide average increases of about 1°C (Tmin) and 2.5°C (HImax), respectively. LSM simulations assuming both land use and warming for 2040 led to summer average increases of up to 2.5°C (Tmin) and 8.3°C (HImax), with the largest increases in areas projected to be converted to residential, industrial and mixed-use types. Our results suggest that urbanization and climate change may significantly increase the average number of summer days that exceed current threshold temperatures for initiating a heat advisory for metropolitan Houston, potentially increasing population exposure to extreme heat. PMID:26863298
NASA Astrophysics Data System (ADS)
Frances, F.; Orozco, I.
2010-12-01
This work presents the assessment of the TETIS distributed hydrological model in mountain basins of the American and Carson rivers in Sierra Nevada (USA) at hourly time discretization, as part of the DMIP2 Project. In TETIS each cell of the spatial grid conceptualizes the water cycle using six tanks connected among them. The relationship between tanks depends on the case, although at the end in most situations, simple linear reservoirs and flow thresholds schemes are used with exceptional results (Vélez et al., 1999; Francés et al., 2002). In particular, within the snow tank, snow melting is based in this work on the simple degree-day method with spatial constant parameters. The TETIS model includes an automatic calibration module, based on the SCE-UA algorithm (Duan et al., 1992; Duan et al., 1994) and the model effective parameters are organized following a split structure, as presented by Francés and Benito (1995) and Francés et al. (2007). In this way, the calibration involves in TETIS up to 9 correction factors (CFs), which correct globally the different parameter maps instead of each parameter cell value, thus reducing drastically the number of variables to be calibrated. This strategy allows for a fast and agile modification in different hydrological processes preserving the spatial structure of each parameter map. With the snowmelt submodel, automatic model calibration was carried out in three steps, separating the calibration of rainfall-runoff and snowmelt parameters. In the first step, the automatic calibration of the CFs during the period 05/20/1990 to 07/31/1990 in the American River (without snow influence), gave a Nash-Sutcliffe Efficiency (NSE) index of 0.92. The calibration of the three degree-day parameters was done using all the SNOTEL stations in the American and Carson rivers. Finally, using previous calibrations as initial values, the complete calibration done in the Carson River for the period 10/01/1992 to 07/31/1993 gave a NSE index of 0.86. The temporal and spatial validation using five periods must be considered in both rivers excellent for discharges (NSEs higher than 0.76) and good for snow distribution (daily spatial coverage errors ranging from -10 to 27%). In conclusion, this work demonstrates: 1.- The viability of automatic calibration of distributed models, with the corresponding personal time saving and maximum exploitation of the available information. 2.- The good performance of the degree-day snowmelt formulation even at hourly time discretization, in spite of its simplicity.
NASA Astrophysics Data System (ADS)
Mohai, Paul; Saha, Robin
2015-12-01
A considerable number of quantitative analyses have been conducted in the past several decades that demonstrate the existence of racial and socioeconomic disparities in the distribution of a wide variety of environmental hazards. The vast majority of these have been cross-sectional, snapshot studies employing data on hazardous facilities and population characteristics at only one point in time. Although some limited hypotheses can be tested with cross-sectional data, fully understanding how present-day disparities come about requires longitudinal analyses that examine the demographic characteristics of sites at the time of facility siting and track demographic changes after siting. Relatively few such studies exist and those that do exist have often led to confusing and contradictory findings. In this paper we review the theoretical arguments, methods, findings, and conclusions drawn from existing longitudinal environmental justice studies. Our goal is to make sense of this literature and to identify the direction future research should take in order to resolve confusion and arrive at a clearer understanding of the processes and contributory factors by which present-day racial and socioeconomic disparities in the distribution of environmental hazards have come about. Such understandings also serve as an important step in identifying appropriate and effective societal responses to ameliorate environmental disparities.
Holmberg, Per; Liljequist, Sture; Wägner, Anna
2009-02-01
The development and distribution of secondary brain lesions, subsequent to ischemic stroke, are of considerable clinical interest but so far only a limited number of studies have investigated the distribution and development of these secondary lesions in detail. In this study, we used an animal model of focal ischemia caused by extradural compression of the sensorimotor cortex. This paradigm of focal ischemia was shown to produce a consistent pattern of secondary lesions located distally from the primary lesion. Functionally the primary brain lesion produced a transient neurological deficit, which was evaluated by daily beam walking tests. Morphological changes were assessed in parallel after the ischemic event using Fluoro-Jade (FJ) staining as a marker of neuronal cell death. Secondary brain lesions were observed in the thalamus as well as in the hippocampus. The first sign of the slowly developing secondary brain lesions was present on day 3 with subsequent lesions being identified until day 16 after the primary ischemia. In addition to the identification of neuronal cell death by the FJ assays, immunostaining for parvalbumin (PA), a marker of GABAergic interneurons, revealed a loss of PA-staining in the pyramidal layer of CA1 on day 3, thus showing a similar time pattern for loss of PA-staining as for the loss of FJ stained cells. Based upon our present results, we suggest that the current animal model of focal ischemia represents a valuable tool for studies concerning the development of secondary remote brain lesions and their association to impaired motor and cognitive functions.
Signatures of present and past melt distribution along fast and intermediate spreading centers
NASA Astrophysics Data System (ADS)
Marjanovic, Milena
The work presented in this dissertation depicts past and present signatures of melt distribution at fast and intermediate spreading centers. The primary goal of the studies included in this thesis is to provide better understanding of melt distribution and variation in melt physical properties within and at the base of oceanic crust formed at these spreading centers. Furthermore, this work examines effects that melt presence might have on formation and structural characteristics of oceanic crust. To explore the above we use geophysical data collected during two expeditions conducted along the Juan de Fuca Ridge (intermediate) and the East Pacific Rise (fast). The major part of the thesis is based on the work conducted on high resolution reflection seismic data that investigate present day intracrustal melt distribution along the East Pacific Rise (EPR) axis extending between 8°20' and 10°10'N. Here, the character of the melt reservoir is examined from different aspects and by using different seismic data analysis methods. By systematic analysis of the seismic reflection data, we show that the axial melt lens (AML) is segmented at different segment scales. Locations of the mapped disruptions in the AML correspond to previously identified tectonic discontinuities well expressed in the seafloor bathymetry. The above result corroborates genetic relationship between tectonic and magmatic segmentation. To examine melt distribution along the EPR, here for the first time we use amplitude variation with angle of incidence (AVA) crossplotting technique that was developed by oil and gas industry experts to look for presence of hydrocarbons. Further data examination for the first time for the mid-ocean ridges show presence of deeper lenses (lenses that are present below the AML). Presence of gaps in these sub-events and their collocation with what is believed to be the location of origin of the last documented eruption occurred in 2005--06, may shed light on the mechanisms behind the mid-ocean ridges volcanic processes. To explore variation in crustal structure and melt distribution at present day along the Juan de Fuca Ridge and relicts of past melt presence near ridge propagators wakes, a combination of gravity and multi-channel seismic data was used. Gravity modeling, constrained by seismic data, showed that robust topography (shallow axial depth and wide axial high) and thicker crust observed for the southern portion of this ridge system originate from enhanced melt supply at the base of the crust. In addition, prominent crustal thickening on the younger crust side of the inner propagators wakes (now on the ridge flanks) is brought into relationship with collocated frozen magma lenses imaged at the base of the crust. Spatial relationship of the two argues for their causal relationship at the time of the crustal formation on the axis. Our study suggests that these frozen lenses represent the record of once molten reservoir that most probably actively participated in the formation of the thicker crust.
The following SAS macros can be used to create a bivariate distribution of usual intake of two dietary components that are consumed nearly every day and to calculate percentiles of the population distribution of the ratio of usual intakes.
Wagman, Jason D; Lukas, Kristen E; Dennis, Patricia M; Willis, Mark A; Carroscia, Joe; Gindlesperger, Curt; Schook, Mandi W
2018-01-01
Zoo-housed bears are prone to exhibiting stereotypic behaviors, generally considered indicators of negative welfare. We explored the effects of a variable-time feeding enrichment schedule on behavioral indicators of welfare in four bear species at Cleveland Metroparks Zoo. We distributed the diets of eight bears in one of five enrichment items, for two consecutive days each, and monitored behavior throughout the day. In Experiment 1, we compared variable-time to fixed-time presentation of enrichment over two, 10-day periods. Overall, bears performed more exploratory behavior when enriched (p < 0.0001). Furthermore, variable-time enrichment was associated with a greater increase in exploratory behavior than fixed-time enrichment when compared to baseline (p < 0.001). Both fixed-time (p unadjusted <0.05, p adjusted = 0.07) and variable-schedule (p unadjusted <0.05, p adjusted = 0.09) enrichment were also associated with similar decreases in abnormal behavior compared to baseline. For Experiment 2, we tested habituation to enrichment over 30 days using multiple items and a semi-variable presentation schedule. Again during the enrichment period, bears exhibited increased exploratory behavior (p < 0.0001) and decreased abnormal behaviors compared to baseline (p unadjusted = 0.05, p adjusted = 0.09). We observed no habituation during the 30-day sustained enrichment period for these behaviors. Collectively, these results suggest that daily, variable-schedule feeding enrichment, with intermittent presentation of unique enrichment items, increases behavioral indicators of positive welfare and decreases behavioral indicators of negative welfare. © 2018 Wiley Periodicals, Inc.
Non-linear multi-objective model for planning water-energy modes of Novosibirsk Hydro Power Plant
NASA Astrophysics Data System (ADS)
Alsova, O. K.; Artamonova, A. V.
2018-05-01
This paper presents a non-linear multi-objective model for planning and optimizing of water-energy modes for the Novosibirsk Hydro Power Plant (HPP) operation. There is a very important problem of developing a strategy to improve the scheme of water-power modes and ensure the effective operation of hydropower plants. It is necessary to determine the methods and criteria for the optimal distribution of water resources, to develop a set of models and to apply them to the software implementation of a DSS (decision-support system) for managing Novosibirsk HPP modes. One of the possible versions of the model is presented and investigated in this paper. Experimental study of the model has been carried out with 2017 data and the task of ten-day period planning from April to July (only 12 ten-day periods) was solved.
Congenital Perisylvian Syndrome presenting as Post-partum Seizures with Preeclampsia.
Agarwal, Arun; Goyal, Manju; Jain, Jainendra; Agarwal, Aakanksha
2017-06-01
Whether preceded by preeclampsia, or occuring without antecedent warning symptoms, eclamptic seizures usually occur in the antepartum period between 20 and 40 weeks of gestation or within a few hours to 2 days postpartum. We report the case of a patient with pre-eclampsia who developed seizures after more than 2 days of delivery. In view of late onset postpartum seizures and non-responsiveness to magnesium sulphate, she was further evaluated and diagnosed to have congenital perisylvian syndrome(CPS). In CPS, polymicrogyric cortex is distributed in variable extensions around the sylvian fissure i.e. a structural malformation of the brain with underlying anomaly of polymicrogyria. © Journal of the Association of Physicians of India 2011.
Io's Magnetospheric Interaction: An MHD Model with Day-Night Asymmetry
NASA Technical Reports Server (NTRS)
Kabin, K.; Combi, M. R.; Gombosi, T. I.; DeZeeuw, D. L.; Hansen, K. C.; Powell, K. G.
2001-01-01
In this paper we present the results of all improved three-dimensional MHD model for Io's interaction with Jupiter's magnetosphere. We have included the day-night asymmetry into the spatial distribution of our mass-loading, which allowed us to reproduce several smaller features or the Galileo December 1995 data set. The calculation is performed using our newly modified description of the pick-up processes that accounts for the effects of the corotational electric field existing in the Jovian magnetosphere. This change in the formulation of the source terms for the MHD equations resulted in significant improvements in the comparison with the Galileo measurements. We briefly discuss the limitations of our model and possible future improvements.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Frick, G.M.; Hoppel, W.A.
1993-11-01
The use of an airship as a platform to conduct atmospheric chemistry, aerosol, and cloud microphysical research is described, and results from demonstration flights made off the Oregon coast are presented. The slow speed of the airship makes it an ideal platform to do high-spatial resolution profiling both vertically and horizontally, and to measure large aerosol and cloud droplet distributions without the difficulties caused by high-speed aircraft sampling. A unique set of data obtained during the demonstration flights show the effect that processing marine boundary layer aerosol through stratus clouds has on the aerosol size distribution. Evidence of new particlemore » formation (nucleation of particles) was also observed on about half the days on which flights were made. 11 refs., 9 figs., 1 tab.« less
Temperature Distribution and Influence Mechanism on Large Reflector Antennas under Solar Radiation
NASA Astrophysics Data System (ADS)
Wang, C. S.; Yuan, S.; Liu, X.; Xu, Q.; Wang, M.; Zhu, M. B.; Chen, G. D.; Duan, Y. H.
2017-10-01
The solar impact on antenna must be lessened for the large reflector antenna operating at high frequencies to have great electromagnetic performances. Therefore, researching the temperature distribution and its influence on large reflector antenna is necessary. The variation of solar incidence angle is first calculated. Then the model is simulated by the I-DEAS software, with the temperature, thermal stress, and thermal distortion distribution through the day obtained. In view of the important influence of shadow on antenna structure, a newly proposed method makes a comprehensive description of the temperature distribution on the reflector and its influence through the day by dividing a day into three different periods. The sound discussions and beneficial summary serve as the scientific foundation for the engineers to compensate the thermal distortion and optimize the antenna structure.
Hydrologic risk analysis in the Yangtze River basin through coupling Gaussian mixtures into copulas
NASA Astrophysics Data System (ADS)
Fan, Y. R.; Huang, W. W.; Huang, G. H.; Li, Y. P.; Huang, K.; Li, Z.
2016-02-01
In this study, a bivariate hydrologic risk framework is proposed through coupling Gaussian mixtures into copulas, leading to a coupled GMM-copula method. In the coupled GMM-Copula method, the marginal distributions of flood peak, volume and duration are quantified through Gaussian mixture models and the joint probability distributions of flood peak-volume, peak-duration and volume-duration are established through copulas. The bivariate hydrologic risk is then derived based on the joint return period of flood variable pairs. The proposed method is applied to the risk analysis for the Yichang station on the main stream of the Yangtze River, China. The results indicate that (i) the bivariate risk for flood peak-volume would keep constant for the flood volume less than 1.0 × 105 m3/s day, but present a significant decreasing trend for the flood volume larger than 1.7 × 105 m3/s day; and (ii) the bivariate risk for flood peak-duration would not change significantly for the flood duration less than 8 days, and then decrease significantly as duration value become larger. The probability density functions (pdfs) of the flood volume and duration conditional on flood peak can also be generated through the fitted copulas. The results indicate that the conditional pdfs of flood volume and duration follow bimodal distributions, with the occurrence frequency of the first vertex decreasing and the latter one increasing as the increase of flood peak. The obtained conclusions from the bivariate hydrologic analysis can provide decision support for flood control and mitigation.
NASA Astrophysics Data System (ADS)
Paparrizos, Spyridon; Matzarakis, Andreas
2017-10-01
The determination of heat requirements in the first developing phases of plants has been expressed as Growing Degree Days (GDD). The current study focuses on three selected study areas in Greece that are characterised by different climatic conditions due to their location and aims to assess the future variation and spatial distribution of Growing Degree Days (GDD) and how these can affect the main cultivations in the study areas. Future temperature data were obtained and analysed by the ENSEMBLES project. The analysis was performed for the future periods 2021-2050 and 2071-2100 with the A1B and B1 scenarios. Spatial distribution was performed using a combination of dynamical and statistical downscaling technique through ArcGIS 10.2.1. The results indicated that for all the future periods and scenarios, the GDD are expected to increase. Furthermore, the increase in the Sperchios River basin will be the highest, followed by the Ardas and the Geropotamos River basins. Moreover, the cultivation period will be shifted from April-October to April-September which will have social, economical and environmental benefits. Additionally, the spatial distribution indicated that in the upcoming years the existing cultivations can find favourable conditions and can be expanded in mountainous areas as well. On the other hand, due to the rough topography that exists in the study areas, the wide expansion of the existing cultivations into higher altitudes is unaffordable. Nevertheless, new more profitable cultivations can be introduced which can find propitious conditions in terms of GDD.
Long-term patterns in fish phenology in the western Dutch Wadden Sea in relation to climate change
NASA Astrophysics Data System (ADS)
van Walraven, Lodewijk; Dapper, Rob; Nauw, Janine J.; Tulp, Ingrid; Witte, Johannes IJ.; van der Veer, Henk W.
2017-09-01
Long-term patterns in fish phenology in the western Dutch Wadden Sea were studied using a 53 year (1960-2013) high resolution time series of daily kom-fyke catches in spring and autumn. Trends in first appearance, last occurrence and peak abundance were analysed for the most common species in relation to mode of life (pelagic, demersal, benthopelagic) and biogeographic guild (northern or southern distribution). Climate change in the western Wadden Sea involved an increase in water temperature from 1980 onwards. The main pattern in first day of occurrence, peak occurrence and last day of occurrence was similar: a positive trend over time and a correlation with spring and summer water temperature. This is counterintuitive; with increasing temperature, an advanced immigration of fish species would be expected. An explanation might be that water temperatures have increased offshore as well and hence fish remain longer there, delaying their immigration to the Wadden Sea. The main trend towards later date of peak occurrence and last day of occurrence was in line with our expectations: a forward shift in immigration into the Wadden Sea implies also that peak abundance is delayed. As a consequence of the increased water temperature, autumn water temperature remains favourable longer than before. For most of the species present, the Wadden Sea is not near the edge of their distributional range. The most striking phenological shifts occurred in those individual species for which the Wadden Sea is near the southern or northern edge of their distribution.
Epidemic of fractures during a period of snow and ice: has anything changed 33 years on?
Al-Azzani, Waheeb; Adam Maliq Mak, Danial; Hodgson, Paul; Williams, Rhodri
2016-01-01
Objectives We reproduced a frequently cited study that was published in the British Medical Journal (BMJ) in 1981 assessing the extent of ‘snow-and-ice’ fractures during the winter period. Setting This study aims to provide an insight into how things have changed within the same emergency department (ED) by comparing the findings of the BMJ paper published 33 years ago with the present date. Participants As per the original study, all patients presenting to the ED with a radiological evidence of fracture during three different 4-day periods were included. The three 4-day periods included 4 days of snow-and-ice conditions and two control 4-day periods when snow and ice was not present; the first was 4 days within the same year, with a similar amount of sunshine hours, and the second was 4 days 1 calendar year later. Primary and secondary outcome measures To identify the frequency, distribution and pattern of fractures sustained in snow-and-ice conditions compared to control conditions as well as comparisons with the index study 33 years ago. Results A total of 293 patients with fractures were identified. Overall, there was a 2.20 (CI 1.7 to 3.0, p <0.01) increase in risk of fracture during snow-and-ice periods compared to control conditions. There was an increase (p <0.01) of fractures of the arm, forearm and wrist (RR 3.2 (CI 1.4 to 7.6) and 2.9 (CI 1.5 to 5.4) respectively). Conclusions While the relative risk was not of the magnitude 33 years ago, the overall number of patients presenting with a fracture during snow-and-ice conditions remains more than double compared to control conditions. This highlights the need for improved understanding of the impact of increased fracture burden on hospitals and more effective preventative measures. PMID:27630066
NASA Astrophysics Data System (ADS)
Hirose, M.; Yamamoto, H.; Nonaka, M.
2008-06-01
Coral planulae settle, then metamorphose and form polyps. This study examined the morphological process of metamorphosis from planulae into primary polyps in the scleractinian corals Acropora nobilis and Acropora microphthalma, using the cnidarian neuropeptide Hym-248 . These two species release eggs that do not contain Symbiodinium. The mode of acquisition of freshly isolated Symbiodinium (zooxanthellae) (FIZ) by the non-symbiotic polyp was also examined. Non-Hym-248 treated swimming Acropora planulae did not develop blastopore, mesenteries or coelenteron until the induction of metamorphosis 16 days after fertilization. The oral pore was formed by invagination of the epidermal layer after formation of the coelenteron in metamorphosing polyps. At 3 days after settlement and metamorphosis, primary polyps exposed to FIZ established symbioses with the Symbiodinium. Two-four days after exposure to FIZ, the distribution of Symbiodinium was limited to the gastrodermis of the pharynx and basal part of the polyps. Eight-ten days after exposure to FIZ, Symbiodinium were present in gastrodermal cells throughout the polyps.
NASA Astrophysics Data System (ADS)
Gaudel, A.; Cooper, O. R.; Barret, B.; Boynard, A.; Clerbaux, C.; Pierre-Francois, C.; Huang, G.; Hurtmans, D.; Kerridge, B. J.; Latter, B.; Le Flochmoen, E.; Liu, X.; Neu, J. L.; Siddans, R.; Wespes, C.; Worden, H. M.; Ziemke, J. R.
2017-12-01
Tropospheric ozone is a greenhouse gas and pollutant detrimental to human health and crop and ecosystem productivity. Since 1990 a large portion of the anthropogenic emissions that react in the atmosphere to produce ozone have shifted from North America and Europe to Asia. This rapid shift, coupled with limited ozone monitoring in developing nations, has left scientists unable to answer the most basic questions: Is ozone continuing to decline in nations with strong emission controls? To what extent is ozone increasing in the developing world? IGAC's Tropospheric Ozone Assessment Report (TOAR) has been designed to answer these questions and this presentation will show the results from the TOAR-Climate initiative, focusing on the present-day distribution and trends of global tropospheric ozone from satellite observations. Five satellite products based on OMI (2 products using two different retrieval methods) and IASI (also 2 products using two different retrieval methods) and the OMI/MLS combined product were intercompared. An important result is the close agreement among the five products regarding the quantification of the total mass of all tropospheric ozone, the so called tropospheric ozone burden (TOB). The mean estimate for TOB between 60° N and 60° S is 296 Tg, with all products agreeing within ± 4%. However, on a regional basis the five satellite products have notable differences and there is no agreement in terms of ozone trends over the past decade. Continuing work is exploring the causes of these differences.
The Statistical Fragmentation Theory of N. F. Mott
NASA Astrophysics Data System (ADS)
Grady, Dennis
2004-07-01
For a brief period during the height of World War II, Neville F. Mott left his position at the University of Bristol and headed up a concerted theoretical effort at Fort Halstead, UK, to investigate the operational science of weapons and armor technology. The seminal achievements resulting from the efforts of the participating scientists are extraordinary and have provided the basis for much of the continuing research in this field over the intervening six decades. N. F. Mott chose to study the phenomenon of the explosive-driven fragmentation of exploding shell cases. The approaches pursued by Mott are documented in several interim reports and open literature publications and offer a fascinating look into the insightful thinking and scientific methods of one of the preeminent physicists of the last century. This presentation offers a perspective into the several theoretical approaches pursued by Mott. In particular, the hallmark relation for the representation of exploding munitions fragmentation data to the present day is the Mott distribution. The efforts of Mott leading to this distribution are explored and a judgment is offered as to whether Mott himself would use this distribution today.
Diel variation of larval fish abundance in the Amazon and Rio Negro.
Araujo-Lima, C A; da Silva, V V; Petry, P; Oliveira, E C; Moura, S M
2001-08-01
Many streams and large rivers present higher ichthyoplankton densities at night. However, in some rivers this does not occur and larvae are equally abundant during the day. Larval drift diel variation is an important information for planning sampling programs for evaluating larval distribution and production. The aim of this study was to test whether the abundance of larval fish was different at either period. We tested it by comparing day and night densities of characiform, clupeiform and siluriform larvae during five years in the Amazon and one year in Rio Negro. We found that larvae of three species of characiform and larvae of siluriform were equally abundant during day and night in the Amazon. Conversely, the catch of Pellona spp. larvae was significantly higher during the day. In Rio Negro, however, larval abundance was higher during the night. These results imply that day samplings estimate adequately the abundance of these characiform and siluriform larvae in the Amazon, but not Pellona larvae. Evaluations of larved densities of Rio Negro will have to consider night sampling.
Developmental changes of mast cell populations in the cerebral meninges of the rat
Michaloudi, Helen; Batzios, Christos; Chiotelli, Maria; Papadopoulos, Georgios C
2007-01-01
It is known that both the dura and the pia mater attract and support the differentiation of mast cells. The present study shows that unevenly distributed mast cells in the cerebral meninges of the rat can be found in perivascular sites and vessel ramification points, but can also be unrelated to the meningeal vasculature. It also documents changes in the number, localization and staining preferences of the mast cells in the two meninges of the developing and mature rat brain. Quantitative examination of all types of histochemically differentiated meningeal mast cells reveals no major (although some exist) differences between right and left side subpopulations, but strongly suggests a different origin and fate of the dural and the pial mast cells. The number of dural mast cells, already high from postnatal day 0, although declining from postnatal day 21 onwards, remains conspicuous up to postnatal day 180. In contrast, pial mast cells are comparatively very few in the first day of the postnatal life, and despite a transient significant increase in the following two weeks, they reach almost zero levels from postnatal day 21. PMID:17822416
Developmental changes of mast cell populations in the cerebral meninges of the rat.
Michaloudi, Helen; Batzios, Christos; Chiotelli, Maria; Papadopoulos, Georgios C
2007-10-01
It is known that both the dura and the pia mater attract and support the differentiation of mast cells. The present study shows that unevenly distributed mast cells in the cerebral meninges of the rat can be found in perivascular sites and vessel ramification points, but can also be unrelated to the meningeal vasculature. It also documents changes in the number, localization and staining preferences of the mast cells in the two meninges of the developing and mature rat brain. Quantitative examination of all types of histochemically differentiated meningeal mast cells reveals no major (although some exist) differences between right and left side subpopulations, but strongly suggests a different origin and fate of the dural and the pial mast cells. The number of dural mast cells, already high from postnatal day 0, although declining from postnatal day 21 onwards, remains conspicuous up to postnatal day 180. In contrast, pial mast cells are comparatively very few in the first day of the postnatal life, and despite a transient significant increase in the following two weeks, they reach almost zero levels from postnatal day 21.
Trenary, Heather R; Creed, Patricia A; Young, Andrea R; Mantha, Madhavi; Schwegel, Carol A; Xue, Jianping; Kohan, Michael J; Herbin-Davis, Karen; Thomas, David J; Caruso, Joseph A; Creed, John T
2012-07-01
In this study, an in vitro synthetic gastrointestinal extraction protocol was used to estimate bioaccessibility of different arsenicals present in 17 rice samples of various grain types that were collected across the United States. The across matrix average for total arsenic was 209 ng/g±153 (\\[xmacr]±2σ). The bioaccessibility estimate produced an across matrix average of 61%±19 (\\[xmacr]±2σ). The across matrix average concentrations of inorganic arsenic (iAs) and dimethylarsinic acid (DMA) were 81 ng/g±67.7 and 41 ng/g±58.1 (\\[xmacr]±2σ), respectively. This distribution of iAs concentrations in rice was combined with the distribution of consumption patterns (from WWEIA) in a Stochastic Human Exposure and Dose Simulator model to estimate population-based exposures. The mean consumption rate for the population as a whole was 15.7 g per day resulting in a 0.98 μg iAs per day exposure. The mean consumption rate for children 1-2 years old was 7 g per day resulting in a 0.48 μg iAs per day exposure. Presystemic biotransformation of DMA in rice was examined using an in vitro assay containing the anaerobic microbiota of mouse cecum. This assay indicated that DMA extracted from the rice was converted to dimethylthioarsinic acid, although a second oxygen-sulfur exchange to produce DMDTA was not observed.
Yin, Jingjing; Qu, Jianguo; Zhang, Wenjie; Lu, Dongrui; Gao, Yucong; Ying, Xixiang; Kang, Tingguo
2014-05-01
Hawthorn leaves, a well-known traditional Chinese medicine, have been widely used for treating cardiovascular and fatty liver diseases. The present study aimed to investigate the therapeutic basis treating fatty liver disease by comparing the tissue distribution of six compounds of hawthorn leaf extract (HLE) in fatty liver rats and healthy rats after oral administration at first day, half month and one month, separately. Therefore, a sensitive and specific HPLC method with internal standard was developed and validated to determine chlorogenic acid, vitexin-4''-O-glucoside, vitexin-2''-O-rhamnoside, vitexin, rutin and hyperoside in the tissues including heart, liver, spleen, kidney, stomach and intestine. The results indicated that the six compounds in HLE presented some bioactivity in treating rat fatty liver as the concentrations of the six compounds varied significantly in inter- and intragroup comparisons (healthy and/or fatty liver group). Copyright © 2013 John Wiley & Sons, Ltd.
Hourly temporal distribution of wind
NASA Astrophysics Data System (ADS)
Deligiannis, Ilias; Dimitriadis, Panayiotis; Koutsoyiannis, Demetris
2016-04-01
The wind process is essential for hydrometeorology and additionally, is one of the basic renewable energy resources. Most stochastic forecast models are limited up to daily scales disregarding the hourly scale which is significant for renewable energy management. Here, we analyze hourly wind timeseries giving emphasis on the temporal distribution of wind within the day. We finally present a periodic model based on statistical as well as hydrometeorological reasoning that shows good agreement with data. Acknowledgement: This research is conducted within the frame of the undergraduate course "Stochastic Methods in Water Resources" of the National Technical University of Athens (NTUA). The School of Civil Engineering of NTUA provided moral support for the participation of the students in the Assembly.
A History of the Andrew File System
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bashear, Derrick
2011-02-22
Derrick Brashear and Jeffrey Altman will present a technical history of the evolution of Andrew File System starting with the early days of the Andrew Project at Carnegie Mellon through the commercialization by Transarc Corporation and IBM and a decade of OpenAFS. The talk will be technical with a focus on the various decisions and implementation trade-offs that were made over the course of AFS versions 1 through 4, the development of the Distributed Computing Environment Distributed File System (DCE DFS), and the course of the OpenAFS development community. The speakers will also discuss the various AFS branches developed atmore » the University of Michigan, Massachusetts Institute of Technology and Carnegie Mellon University.« less
Coronagraph particulate measurements. Skylab flight experiment T025
NASA Technical Reports Server (NTRS)
Greenberg, J. M.; Schuerman, D. W.; Giovane, F.; Wang, R. T.; Hardy, D. C.
1975-01-01
Major results of the Skylab T025 Coronagraph experiment designed to monitor the particulate contamination about the spacecraft and to study the earth's atmospheric aerosol distribution are presented. A model for comet outbursts based on the properties of amorphous ice and ground based narrow-band and white light photography of comet Kohoutek ten days to perihelion are included. The effect of atmospheric refraction on the analysis of the T025 atmospheric data was also investigated.
ERIC Educational Resources Information Center
Liu, Fengshu
2006-01-01
Studies on the effect of only-child status on girls' education indicate that the only-child policy has had an unintended consequence of engendering a child-centered culture with a strong belief and shared interest among the urban community in educating the only-child regardless of the child's sex. As the distribution of education by sex is…
Multiparty Quantum Secret Sharing of Key Using Practical Faint Laser Pulses
NASA Astrophysics Data System (ADS)
Zhang, Zhan-Jun; Man, Zhong-Xiao
2005-07-01
Based on a bidirectional quantum key distribution protocol [Phys. Rev. A 70 (2004) 012311], we propose a (m-1,m-1)-threshold scheme of m (m >= 3)-party quantum secret sharing of key by using practical faint laser pulses. In our scheme, if all the m-1 sharers collaborate, they can obtain the joint secret key from the message sender. Our scheme is more feasible according to the present-day technology.
Haq, Shaji S; Kodak, Tiffany; Kurtz-Nelson, Evangeline; Porritt, Marilynn; Rush, Kristin; Cariveau, Tom
2015-01-01
We replicated and extended the findings of Haq and Kodak (2015) by evaluating the efficiency of massed and distributed practice for teaching tacts and textual and intraverbal behavior to 3 children with autism. Massed practice included all practice opportunities conducted on 1 day during each week, and distributed practice included practice opportunities conducted across several days during the week. The results indicated that distributed practice was more efficient for all participants. Suggested areas for future research and implications for practice are discussed. © Society for the Experimental Analysis of Behavior.
Sánchez, Hermes U Ramírez; García, María D Andrade; Bejaran, Rubén; Guadalupe, Mario E García; Vázquez, Antonio Wallo; Toledano, Ana C Pompa; Villasenor, Odila de la Torre
2009-06-15
In the large cities, the disordered urban development, the industrial activities, and the transport, have caused elevated concentrations of polluting agents and possible risks to the health of the population. The metropolises located in valleys with little ventilation (such as the Urban Area of Guadalajara: UAG) present low dispersion of polluting agents can cause high risk of respiratory and cardiovascular diseases. The objective of this work was to describe the spatial-temporal distribution of the atmospheric polluting agents: carbon monoxide (CO), nitrogen dioxide (NO(2)), sulfur dioxide (SO(2)), particles smaller than 10 microns (microm) (PM(10)) and ozone (O(3)) in the UAG during the period 2000-2005. A spatial-temporal distribution analysis was made by means of graphic interpolation (Kriging method) of the statistical parameters of CO, NO(2), SO(2), PM(10) and O(3) with the collected data from eight stations of atmospheric monitoring in the UAG. The results show that the distributions of the atmospheric polluting agents are variable during the analyzed years. The polluting agent with highest concentration is PM(10) (265.42 microg/m(3)), followed by O(3) (0.11 ppm), NO(2) (0.11 ppm), CO (9.17 ppm) and SO(2) (0.05 ppm). The most affected zone is the southeast of the UAG. The results showed that an important percentage of days exceed the Mexican norms of air quality (93-199 days/year).
Whose Culture?: Monolithic Cultures and Subcultures in Early Childhood Settings
ERIC Educational Resources Information Center
Halttunen, Leena
2017-01-01
In Finland, day care centre directors have traditionally led only a single unit, but after the recent merging of many units, most directors simultaneously lead several, physically separate units. These organizations are called distributed organizations. This study was carried out in two distributed day care organizations. The findings are based on…
NASA Technical Reports Server (NTRS)
Levine, Joel S.; Summers, Michael E.
2008-01-01
In the early history of Mars, volcanic activity associated with the formation of the Tharsis ridge produced a very large amount of atmospheric SO2--on the order of a bar of atmospheric SO2. In the present-day atmosphere of Mars, the lifetime of SO2 is relatively short with a lifetime of less than a day. The short lifetime of SO2 in the present Mars atmosphere makes the production of significant levels of H2SO4 very difficult since the SO2 may be destroyed by various chemical and photochemical processes before the SO2 can be converted to H2SO4. However, photochemical calculations performed and described here, indicate that enhanced atmospheric levels of CO2 in the early atmosphere of Mars resulted in a significantly enhanced atmospheric lifetime for SO2 up to several years. With a significantly enhanced atmospheric lifetime, SO2 could readily form large amounts of H2SO4, which precipitated out of the atmosphere in the form of droplets. The precipitated H2SO4 then reacted with potential surface carbonates, destroying the carbonates and resulting in the abundant and widespread distribution of sulfates on the surface of Mars as detected by recent Mars missions.
Physician Dispensing of Oxycodone and Other Commonly Used Opioids, 2000-2015, United States.
Mack, Karin Ann; Jones, Christopher McCall; McClure, Roderick John
2018-05-01
An average of 91 people in the United States die every day from an opioid-related overdose (including prescription opioids and heroin). The direct dispensing of opioids from health care practitioner offices has been linked to opioid-related harms. The objective of this study is to describe the changing nature of the volume of this type of prescribing at the state level. This descriptive study examines the distribution of opioids by practitioners using 1999-2015 Automation of Reports and Consolidated Orders System data. Analyses were restricted to opioids distributed to practitioners. Amount distributed (morphine milligram equivalents [MMEs]) and number of practitioners are presented. Patterns of distribution to practitioners and the number of practitioners varied markedly by state and changed dramatically over time. Comparing 1999 with 2015, the MME distributed to dispensing practitioners decreased in 16 states and increased in 35. Most notable was the change in Florida, which saw a peak of 8.94 MMEs per 100,000 persons in 2010 (the highest distribution in all states in all years) and a low of 0.08 in 2013. This study presents the first state estimates of office-based dispensing of opioids. Increases in direct dispensing in recent years may indicate a need to monitor this practice and consider whether changes are needed. Using controlled substances data to identify high prescribers and dispensers of opioids, as well as examining overall state trends, is a foundational activity to informing the response to potentially high-risk clinical practices.
NASA Technical Reports Server (NTRS)
Reagan, J. A.; Byrne, D. M.; Herman, B. M.; King, M. D.; Spinhirne, J. D.
1980-01-01
A method is presented for inferring both the size distribution and the complex refractive index of atmospheric particulates from combined bistatic-monostatic lidar and solar radiometer observations. The basic input measurements are spectral optical depths at several visible and near-infrared wavelengths as obtained with a solar radiometer and backscatter and angular scatter coefficients as obtained from a biostatic-monostatic lidar. The spectral optical depth measurements obtained from the radiometer are mathematically inverted to infer a columnar particulate size distribution. Advantage is taken of the fact that the shape of the size distribution obtained by inverting the particulate optical depth is relatively insensitive to the particle refractive index assumed in the inversion. Bistatic-monostatic angular scatter and backscatter lidar data are then processed to extract an optimum value for the particle refractive index subject to the constraint that the shape of the particulate size distribution be the same as that inferred from the solar radiometer data. Specifically, the scattering parameters obtained from the bistatic-monostatic lidar data are compared with corresponding theoretical computations made for various assumed refractive index values. That value which yields best agreement, in a weighted least squares sense, is selected as the optimal refractive index estimate. The results of this procedure applied to a set of simulated measurements as well as to measurements collected on two separate days are presented and discussed.
The stellar orbit distribution in present-day galaxies inferred from the CALIFA survey
NASA Astrophysics Data System (ADS)
Zhu, Ling; van de Ven, Glenn; Bosch, Remco van den; Rix, Hans-Walter; Lyubenova, Mariya; Falcón-Barroso, Jesús; Martig, Marie; Mao, Shude; Xu, Dandan; Jin, Yunpeng; Obreja, Aura; Grand, Robert J. J.; Dutton, Aaron A.; Macciò, Andrea V.; Gómez, Facundo A.; Walcher, Jakob C.; García-Benito, Rubén; Zibetti, Stefano; Sánchez, Sebastian F.
2018-03-01
Galaxy formation entails the hierarchical assembly of mass, along with the condensation of baryons and the ensuing, self-regulating star formation1,2. The stars form a collisionless system whose orbit distribution retains dynamical memory that can constrain a galaxy's formation history3. The orbits dominated by ordered rotation, with near-maximum circularity λz ≈ 1, are called kinematically cold, and the orbits dominated by random motion, with low circularity λz ≈ 0, are kinematically hot. The fraction of stars on `cold' orbits, compared with the fraction on `hot' orbits, speaks directly to the quiescence or violence of the galaxies' formation histories4,5. Here we present such orbit distributions, derived from stellar kinematic maps through orbit-based modelling for a well-defined, large sample of 300 nearby galaxies. The sample, drawn from the CALIFA survey6, includes the main morphological galaxy types and spans a total stellar mass range from 108.7 to 1011.9 solar masses. Our analysis derives the orbit-circularity distribution as a function of galaxy mass and its volume-averaged total distribution. We find that across most of the considered mass range and across morphological types, there are more stars on `warm' orbits defined as 0.25 ≤ λz ≤ 0.8 than on either `cold' or `hot' orbits. This orbit-based `Hubble diagram' provides a benchmark for galaxy formation simulations in a cosmological context.
Hair Follicle Nevus Located on the Chin of an Infant: Case Report and Review of Literature.
Larson, Krista N; O'Shea, Patrick; Zedek, Daniel C; Morrell, Dean S
2016-01-01
Hair follicle nevi are rare, benign, congenital hamartomas that usually occur in the distribution of the first brachial arch. Histopathologically, the distinction between hair follicle nevus, trichofolliculoma, and accessory tragus has recently come into question, and it may be that they are all on a spectrum of the same condition. We report the case of a 7-day-old boy who presented with a "tag"-like lesion on his midline chin that had been present since birth. Biopsy of the lesion proved it to be a hair follicle nevus. © 2016 Wiley Periodicals, Inc.
Helium refrigeration considerations for cryomodule design
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ganni, V.; Knudsen, P.
Many of the present day accelerators are based on superconducting radio frequency (SRF) cavities, packaged in cryo-modules (CM), which depend on helium refrigeration at sub-atmospheric pressures, nominally 2 K. These specialized helium refrigeration systems are quite cost intensive to produce and operate. Particularly as there is typically no work extraction below the 4.5-K supply, it is important that the exergy loss between this temperature level and the CM load temperature(s) be minimized by the process configuration choices. This paper will present, compare and discuss several possible helium distribution process arrangements to support the CM loads.
Quantum Communication without Alignment using Multiple-Qubit Single-Photon States
NASA Astrophysics Data System (ADS)
Aolita, L.; Walborn, S. P.
2007-03-01
We propose a scheme for encoding logical qubits in a subspace protected against collective rotations around the propagation axis using the polarization and transverse spatial degrees of freedom of single photons. This encoding allows for quantum key distribution without the need of a shared reference frame. We present methods to generate entangled states of two logical qubits using present day down-conversion sources and linear optics, and show that the application of these entangled logical states to quantum information schemes allows for alignment-free tests of Bell’s inequalities, quantum dense coding, and quantum teleportation.
Low-energy ion distribution functions on a magnetically quiet day at geostationary altitude /L = 7/
NASA Technical Reports Server (NTRS)
Singh, N.; Raitt, W. J.; Yasuhara, F.
1982-01-01
Ion energy and pitch angle distribution functions are examined for a magnetically quiet day using averaged data from ATS 6. For both field-aligned and perpendicular fluxes, the populations have a mixture of characteristic energies, and the distribution functions can be fairly well approximated by Maxwellian distributions over three different energy bands in the range 3-600 eV. Pitch angle distributions varying with local time, and energy distributions are used to compute total ion density. Pitch angle scattering mechanisms responsible for the observed transformation of pitch angle distribution are examined, and it is found that a magnetic noise of a certain power spectral density belonging to the electromagnetic ion cyclotron mode near the ion cyclotron frequency can be effective in trapping the field aligned fluxes by pitch angle scattering.
Resolving runaway electron distributions in space, time, and energy
Paz-Soldan, Carlos; Cooper, C. M.; Aleynikov, P.; ...
2018-05-01
Areas of agreement and disagreement with present-day models of RE evolution are revealed by measuring MeV-level bremsstrahlung radiation from runaway electrons (REs) with a pinhole camera. Spatially-resolved measurements localize the RE beam, reveal energy-dependent RE transport, and can be used to perform full two-dimensional (energy and pitch-angle) inversions of the RE phase space distribution. Energy-resolved measurements find qualitative agreement with modeling on the role of collisional and synchrotron damping in modifying the RE distribution shape. Measurements are consistent with predictions of phase-space attractors that accumulate REs, with non-monotonic features observed in the distribution. Temporally-resolved measurements find qualitative agreement with modelingmore » on the impact of collisional and synchrotron damping in varying the RE growth and decay rate. Anomalous RE loss is observed and found to be largest at low energy. As a result, possible roles for kinetic instability or spatial transport to resolve these anomalies are discussed.« less
Resolving runaway electron distributions in space, time, and energy
DOE Office of Scientific and Technical Information (OSTI.GOV)
Paz-Soldan, Carlos; Cooper, C. M.; Aleynikov, P.
Areas of agreement and disagreement with present-day models of RE evolution are revealed by measuring MeV-level bremsstrahlung radiation from runaway electrons (REs) with a pinhole camera. Spatially-resolved measurements localize the RE beam, reveal energy-dependent RE transport, and can be used to perform full two-dimensional (energy and pitch-angle) inversions of the RE phase space distribution. Energy-resolved measurements find qualitative agreement with modeling on the role of collisional and synchrotron damping in modifying the RE distribution shape. Measurements are consistent with predictions of phase-space attractors that accumulate REs, with non-monotonic features observed in the distribution. Temporally-resolved measurements find qualitative agreement with modelingmore » on the impact of collisional and synchrotron damping in varying the RE growth and decay rate. Anomalous RE loss is observed and found to be largest at low energy. As a result, possible roles for kinetic instability or spatial transport to resolve these anomalies are discussed.« less
NASA Technical Reports Server (NTRS)
Goldhirsh, J.
1978-01-01
Yearly, monthly, and time of day fade statistics are presented and characterized. A 19.04 GHz yearly fade distribution, corresponding to a second COMSTAR beacon frequency, is predicted using the concept of effective path length, disdrometer, and rain rate results. The yearly attenuation and rain rate distributions follow with good approximation log normal variations for most fade and rain rate levels. Attenuations were exceeded for the longest and shortest periods of times for all fades in August and February, respectively. The eight hour time period showing the maximum and minimum number of minutes over the year for which fades exceeded 12 db were approximately between 1600 to 2400, and 0400 to 1200 hours, respectively. In employing the predictive method for obtaining the 19.04 GHz fade distribution, it is demonstrated theoretically that the ratio of attenuations at two frequencies is minimally dependent of raindrop size distribution providing these frequencies are not widely separated.
Climate-driven C4 plant distributions in China: divergence in C4 taxa
Wang, Renzhong; Ma, Linna
2016-01-01
There have been debates on the driving factors of C4 plant expansion, such as PCO2 decline in the late Micocene and warmer climate and precipitation at large-scale modern ecosystems. These disputes are mainly due to the lack of direct evidence and extensive data analysis. Here we use mass flora data to explore the driving factors of C4 distribution and divergent patterns for different C4 taxa at continental scale in China. The results display that it is mean annual climate variables driving C4 distribution at present-day vegetation. Mean annual temperature is the critical restriction of total C4 plants and the precipitation gradients seem to have much less impact. Grass and sedge C4 plants are largely restricted to mean annual temperature and precipitation respectively, while Chenopod C4 plants are strongly restricted by aridity in China. Separate regression analysis can succeed to detect divergences of climate distribution patterns of C4 taxa at global scale. PMID:27302686
A public study of the lifetime distribution of soap films
NASA Astrophysics Data System (ADS)
Tobin, S. T.; Meagher, A. J.; Bulfin, B.; Möbius, M.; Hutzler, S.
2011-08-01
We present data for the lifetime distribution of soap films made from commercial dish-washing solution and contained in sealed cylinders. Data for over 2500 films were gathered during a 2-month exhibition on the science and art of bubbles and foams in Dublin's Science Gallery. Visitors to the gallery were invited to create 10-20 parallel soap films in acrylic tubes which were sealed with cork stoppers. Individual film bursts occurred at random and were uncorrelated. The total number of remaining films in the tubes was recorded every day. Visitors could monitor the status of their soap film tube and the daily updated histogram of the lifetime of all films. The histogram of the bubble lifetimes is well described by a Weibull distribution, which indicates that the failure rate is not constant and increases over time. Unsealed cylinders show drastically reduced film lifetimes. This experiment illustrates the difference between the unpredictability of the lifetime of individual films and the existence of a well-defined lifetime distribution for the ensemble.
Variation of the shower lateral spread with air temperature at the ground
NASA Astrophysics Data System (ADS)
Wilczyńska, B.; Engel, R.; Homola, P.; Keilhauer, B.; Klages, H.; Pękala, J.; Wilczyński, H.
The vertical profile of air density at a given site varies considerably with time. Well understood seasonal differences are present, but sizeable effects on shorter time scales, like day to night or day to day variations, are also observed. In consequence, the Moliere radius changes, influencing the lateral distribution of particles in the air showers and therefore may influence the shower detection in surface detector arrays. In air shower reconstruction, usually seasonal average profiles of the atmosphere are used, because local daily measurements of the profile are rarely available. Therefore, the daily fluctuations of the atmosphere are not accounted for. This simplification increases the inaccuracies of shower reconstruction. We show that a universal correlation exists between the ground temperature and the shape of the atmospheric profile, up to altitudes of several kilometers, hence providing a method to reduce inaccuracies in shower reconstruction due to weather variation.
Semi-annual report of the Department of Energy Quality Assessment Program
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sanderson, C.G.; Scarpitta, S.C.
1992-01-02
This report presents the results from the analysis of the 35th set of environmental quality assessment samples (QAP XXXV) that were received on or before December 5, 1991. This Quality Assessment Program (QAP) is designed to test the quality of the environmental measurements being reported to the Department of Energy by its contractors. Since 1976, real or synthetic environmental samples that have been prepared and thoroughly analyzed at the Environmental Measurements Laboratory (EML) have been distributed at first quarterly and then semi-annually to these contractors. Their results, which are returned to EML within 90 days, are compiled with EML`s resultsmore » and are reported back to the participating contractors 30 days later. A summary of the reported results is available to the participants 3 days after the reporting deadline via a modem-telephone connection to the EML computer.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sanderson, C.G.; Scarpitta, S.C.
1992-07-01
This report presents the results from the analysis of the 36th set of environmental quality assessment samples (QAP 36) that were received on or before January 2, 1992. This Quality Assessment Program (QAP) is designed to test the quality of the environmental measurements being reported to the Department of Energy by its contractors. Since 1976, real or synthetic environmental samples that have been prepared and thoroughly analyzed at the Environmental Measurements Laboratory (EML) have been distributed at first quarterly and then semi-annually to these contractors. Their results, which are returned to EML within 90 days, are complied with EML`s resultsmore » and are reported back to the participating contractors 30 days later. A summary of the reported results is available to the participants 3 days after the reporting deadline via a modem-telephone connection to the EML computer.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sanderson, C.G.; Greenlaw, P.
1996-02-01
This report presents the results from the analysis of the 43rd set of environmental quality assessment samples (QAP XLIII) that were received on or before December 1, 1995. This Quality Assessment Program (QAP) is designed to test the quality of the environmental measurements being reported to the Department of Energy by its contractors. Since 1976, real or synthetic environmental samples that have been prepared and thoroughly analyzed at the Environmental Measurements Laboratory (EML) have been distributed at first quarterly and then semi-annually to these contractors. Their results, which are returned to EML within 90 days, are compiled with EML`s resultsmore » and are reported back to the participating contractors 30 days later. A summary of the reported results is available to the participants 2 days after the reporting deadline via a modem-telephone connection to the EML computer.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sanderson, C.G.; Greenlaw, P.; Pan, V.
1995-07-03
This report presents the results from the analysis of the 42st set of environmental quality assessment samples (QAP XLII) that were received on or before June 1, 1995. This Quality Assessment Program (QAP) is designed to test the quality of the environmental measurements being reported to the Department of Energy by its contractors. Since 1976, real or synthetic environmental samples that have been prepared and thoroughly analyzed at the Environmental Measurements Laboratory (EML) have been distributed at first quarterly and then semi-annually to these contractors. Their results, which are returned to EML within 90 days, are compiled with EML`s resultsmore » and are reported back to the participating contractors 30 days later. A summary of the reported results is available to the participants 2 days after the reporting deadline via a modem-telephone connection to the EML computer.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Greenlaw, P.D.
1998-01-01
This Quality Assessment Program (QAP) is designed to test the quality of the environmental measurements being reported to the Department of Energy by its contractors. Since 1976, real or synthetic environmental samples that have been prepared and thoroughly analyzed at the Environmental Measurements Laboratory (EML) have been distributed at first quarterly and then semi-annually to these contractors. Their results, which are returned to EML within 90 days, are compiled with EML`s results and are reported back to the participating contractors 30 days later. A summary of the reported results is available to the participants 4 days after the reporting deadlinemore » via the Internet at www.eml.doe.gov. This report presents the results from the analysis of the 47th set of environmental quality assessment samples (QAP XLVII) that were received on or before December 1, 1997.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sanderson, C.G.; Klusek, C.S.
1993-07-01
This Quality Assessment Program (QAP) is designed to test the quality of the environmental measurements being reported to the Department of Energy by its contractors. Since 1976, real or synthetic environmental samples that have been prepared and thoroughly analyzed at the Environmental Measurements Laboratory (EML) have been distributed at first quarterly and then semi-annually to these contractors. Their results, which are returned to EML within 90 days, are compiled with EML`s results and are reported back to the participating contractors 30 days later. A summary of the reported results is available to the participants 3 days after the reporting deadlinemore » via a modem-telephone connection to the EML computer. This report presents the results from the analysis of the 38th set of environmental quality assessment samples (QAP XXXVIII) that were received on or before June 2, 1993.« less
Bio-Ecology of the Louse, Upupicola upupae, Infesting the Common Hoopoe, Upupa epops
Agarwal, G. P; Ahmad, Aftab; Rashmi, Archna; Arya, Gaurav; Bansal, Nayanci; Saxena, A.K.
2011-01-01
The population characteristics of the louse, Upupicola upupae (Shrank) (Mallophaga: Philopteridae: Ishnocera), infesting the Common Hoopae, Upupa epops L. (Aves: Upupiformes), were recorded during 2007–08 in District Rampur, Uttar Pradesh India. The pattern of frequency distribution of the louse conformed to the negative binomial model. The lice and its nits were reared in vitro at 35 ± 1° C, 75–82 % RH, on a feather diet. The data obtained was used to construct the life table and to determine the intrinsic rate of natural increase (0.035 female/day), the net reproductive rate was 3.67 female eggs/female, the generation time was 37 days, and the doubling time of the population was 19 days. The chaetotaxy of the three nymphal instars has also been noted to record their diagnostic characteristics. Information on egg morphology and antennal sensilla is also presented. PMID:21861650
Lucey, Anna; Labaja, Jessica; So, Catherine Lee; Snow, Sally; Ponzo, Alessandro
2014-01-01
This study represents the first description of whale sharks, Rhincodon typus, occurring at a provisioning site in Oslob, Cebu, Philippines. Frequent observations of sharks are often difficult, even at tourism sites, giving rise to provisioning activities to attract them. The present study provides repeated longitudinal data at a site where daily provisioning activities took place, and whale sharks were present every day. A total of 158 individual whale sharks were photographically identified between Mar 2012 and Dec 2013, with 129 males (82%), 19 females (12%) and 10 (6%) of undetermined sex. Mean estimated total length was 5.5 m (±1.3 m S.D.). Twenty individuals were measured with laser photogrammetry to validate researchers’ estimated sizes, yielding a good correlation (r2 = 0.83). Fifty-four (34%) individuals were observed being hand-fed by local fishermen (provisioned), through in-water behavioural observations. Maximum likelihood methods were used to model mean residency time of 44.9 days (±20.6 days S.E.) for provisioned R. typus contrasting with 22.4 days (±8.9 days S.E.) for non-provisioned individuals. Propeller scars were observed in 47% of the animals. A mean of 12.7 (±4.3 S.D.) R. typus were present in the survey area daily, with a maximum of 26 individuals (Aug 10 2013) and a minimum of 2 (Dec 6 2012). Twelve (8%) individuals were seen on at least 50% of survey days (n = 621), with a maximum residency of 572 days for one individual (P-396). Twenty four individuals were photographically identified across regional hotsposts, highlighting the species’ migratory nature and distribution. Extended residency and differences in lagged identification rates suggest behavioural modification on provisioned individuals, underlying the necessity for proper management of this tourism activity. PMID:25279256
Transverse Aeolian Ridges (TARs) on Mars II: Distributions, orientations, and ages
NASA Astrophysics Data System (ADS)
Berman, Daniel C.; Balme, Matthew R.; Rafkin, Scot C. R.; Zimbelman, James R.
2011-05-01
Transverse Aeolian Ridges (TARs), 10 m scale, ripple-like aeolian bedforms with simple morphology, are widespread on Mars but it is unknown what role they play in Mars' wider sediment cycle. We present the results of a survey of all Mars Global Surveyor Narrow angle images in a pole-to-pole study area, 45° longitude wide. Following on from the classification scheme and preliminary surveys of Balme et al. (Balme, M.R., Berman, D.C., Bourke, M.C., Zimbelman, J.R. [2008a]. Geomorphology 101, 703-720) and Wilson and Zimbelman (Wilson, S.A., Zimbelman, J.R. [2004]. J. Geophys. Res. 109 (E10). doi: 10.1029/2004JE002247) we searched more than 10,000 images, and found that over 2000 reveal at least 5% areal cover by TARs. The mean TAR areal cover in the study area is about 7% (3% in the northern hemisphere and 11% in the southern hemisphere) but TARs are not homogenously distributed - they are concentrated in the mid-low latitudes and almost absent poleward of 35°N and 55°S. We found no clear correlation between TAR distribution and any of thermal inertia, kilometer-scale roughness, or elevation. We did find that TARs are less common at extremes of elevation. We found that TARs are most common near the equator (especially in the vicinity of Meridiani Planum, in which area they have a distinctive "barchan-like" morphology) and in large southern-hemisphere impact craters. TARs in the equatorial band are usually associated with outcrops of layered terrain or steep slopes, hence their relative absence in the northern hemisphere. TARs in the southern hemisphere are most commonly associated with low albedo, intercrater dune fields. We speculate that the mid-latitude mantling terrain (e.g., Mustard, J.F., Cooper, C.D., Rifkin, M.K. [2001]. Nature 412, 411-414; Kreslavsky, M.A., Head, J.W. [2002]. J. Geophys. Res. 29 (15). doi: 10.1029/2002GL015392) could also play a role in covering TARs or inhibiting saltation. We compared TAR distribution with general circulation model (GCM) climate data for both surface wind shear stress and wind direction. We performed GCM runs at various obliquity values to simulate the effects of changing obliquity on recent Mars climate. We found good general agreement between TAR orientation and GCM wind directions from present day obliquity conditions in many cases, but found no good correlation between wind shear stress and TAR distribution. We performed preliminary high resolution crater count studies of TARs in both equatorial and southern intracrater dunefield settings and compared these to superposition relationships between TARs and large dark dunes. Our results show that TARs near dunefield appear to be younger than TARs in the equatorial regions. We infer that active saltation from the large dunes keeps TARs active, but that TARs are not active under present day condition when distal to large dunes - perhaps supporting the interpretation that TARs are granule ripples. We conclude that local geology, rather than wind strength, controls TAR distribution, but that their orientation matches present-day regional wind patterns in most cases. We suggest that TARs are likely most (perhaps only) active today when they are proximal to large dark dune fields.
New Particle Formation Events During 2013 in Hada Al Sham, Saudi-Arabia
NASA Astrophysics Data System (ADS)
Neitola, K.; Hyvärinen, A.; Lihavainen, H.; Alghamdi, M.; Hussein, T.; Khodeir, M.; Shehata, A.; Laaksonen, A. J.; Kulmala, M. T.
2014-12-01
New particle formation (NPF) is the dominant source of aerosol particles in the atmosphere and plays an important role in the global climate (Kulmala et al., 2013). NPF events has been observed in various places around the world (Kulmala et al., 2007). Arabian Peninsula has one of the highest aerosol burdens due to dust storms, local petroleum industry, traffic and advection from southern Asia. Here we present results of new particle formation event analysis from the first full year of measurements in the new measurement station in Hada Al Sham, Saudi-Arabia. The background station in Hada Al Sham (21.802° North, 39.729° East, 254 m a.s.l.) was founded at the end of 2012 on an agricultural test field 60 km to southeast from the city of Jeddah. The terrain around the station is arid desert with very scarce yearly precipitation. There are no local pollution sources. Main instrumentation include: PM2.5 and PM10, number size distribution (7 nm - 10 μm) and total concentration, absorption and scattering coefficients, and the basic weather parameters. We analysed the twin DMPS data from year 2013 classifying new particle formation events by visual day-to-day method. The days were classified following the principal presented in Dal Maso et al., (2005). The data coverage was 264 days (72.3 %) of the year. 210 Days (79.5 %) were classified as NPF event (Class I and II) days, 37 days (14.0 %) as undefined and 17 days (6.4 %) as non-event days. The analysis of the NPF event days was considered again as the freshly formed particles was observed shrinking after the original growth in most of the NPF event days. Typical event day DMPS data with a shrinking mode of particles is presented in Fig.1. Some of the days involved simultaneous shrinking and growth of the particles. Table 1 summarizes the frequency of each type of event day. Events G S G + S unclear 210 25 102 33 50 Days 100 11.9 48.6 15.7 23.8 (%) Table 1. Reclassification of the event days (classes I and II). G is clear growth, S is clear shrinkage, G + S is both growth and shrinkage and unclear is not clear in either way.ReferencesM. Dal Maso, et al. (2005). Bor. Env. Res., 10, 323-336.M. Kulmala, et al. (2006). Atmos. Chem. Phys., 6, 787-793. M. Kulmala, et al. (2013). Science, 336, 943-946.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kovilakam, Mahesh; Mahajan, Salil; Saravanan, R.
Here, we alleviate the bias in the tropospheric vertical distribution of black carbon aerosols (BC) in the Community Atmosphere Model (CAM4) using the Cloud-Aerosol and Infrared Pathfinder Satellite Observations (CALIPSO)-derived vertical profiles. A suite of sensitivity experiments are conducted with 1x, 5x, and 10x the present-day model estimated BC concentration climatology, with (corrected, CC) and without (uncorrected, UC) CALIPSO-corrected BC vertical distribution. The globally averaged top of the atmosphere radiative flux perturbation of CC experiments is ~8–50% smaller compared to uncorrected (UC) BC experiments largely due to an increase in low-level clouds. The global average surface temperature increases, the globalmore » average precipitation decreases, and the ITCZ moves northward with the increase in BC radiative forcing, irrespective of the vertical distribution of BC. Further, tropical expansion metrics for the poleward extent of the Northern Hemisphere Hadley cell (HC) indicate that simulated HC expansion is not sensitive to existing model biases in BC vertical distribution.« less
Kovilakam, Mahesh; Mahajan, Salil; Saravanan, R.; ...
2017-09-13
Here, we alleviate the bias in the tropospheric vertical distribution of black carbon aerosols (BC) in the Community Atmosphere Model (CAM4) using the Cloud-Aerosol and Infrared Pathfinder Satellite Observations (CALIPSO)-derived vertical profiles. A suite of sensitivity experiments are conducted with 1x, 5x, and 10x the present-day model estimated BC concentration climatology, with (corrected, CC) and without (uncorrected, UC) CALIPSO-corrected BC vertical distribution. The globally averaged top of the atmosphere radiative flux perturbation of CC experiments is ~8–50% smaller compared to uncorrected (UC) BC experiments largely due to an increase in low-level clouds. The global average surface temperature increases, the globalmore » average precipitation decreases, and the ITCZ moves northward with the increase in BC radiative forcing, irrespective of the vertical distribution of BC. Further, tropical expansion metrics for the poleward extent of the Northern Hemisphere Hadley cell (HC) indicate that simulated HC expansion is not sensitive to existing model biases in BC vertical distribution.« less
NASA Technical Reports Server (NTRS)
Kremser, G.; Stuedemann, W.; Wilken, B.; Gloeckler, G.; Hamilton, D. C.
1985-01-01
Observations of charge state distributions of oxygen and carbon are presented that were obtained with the charge-energy-mass spectrometer onboard the AMPTE/CCE spacecraft. Data were selected for two different local time sectors (apogee at 1300 LT and 0300 LT, respectively), three L-ranges (4-6, 6-8, and greater than 8), and quiet to moderately disturbed days (Kp less than or equal to 4). The charge state distributions reveal the existence of all charge states of oxygen and carbon in the magnetosphere. The relative importance of the different charge states strongly depends on L and much less on local time. The observations confirm that the solar wind and the ionosphere contribute to the oxygen population, whereas carbon only originates from the solar wind. The L-dependence of the charge state distributions can be interpreted in terms of these different ion sources and of charge exchange and diffusion processes that largely influence the distribution of oxygen and carbon in the magnetosphere.
Antonini, James M; Afshari, Aliakbar; Meighan, Terence G; McKinney, Walter; Jackson, Mark; Schwegler-Berry, Diane; Burns, Dru A; LeBouf, Ryan F; Chen, Bean T; Shoeb, Mohammad; Zeidler-Erdely, Patti C
2017-01-01
Resistance spot welding is a common process to join metals in the automotive industry. Adhesives are often used as sealers to seams of metals that are joined. Anti-spatter compounds sometimes are sprayed onto metals to be welded to improve the weldability. Spot welding produces complex aerosols composed of metal and volatile compounds (VOCs) which can cause lung disease in workers. Male Sprague-Dawley rats (n = 12/treatment group) were exposed by inhalation to 25 mg/m 3 of aerosol for 4 h/day × 8 days during spot welding of galvanized zinc (Zn)-coated steel in the presence or absence of a glue or anti-spatter spray. Controls were exposed to filtered air. Particle size distribution and chemical composition of the generated aerosol were determined. At 1 and 7 days after exposure, bronchoalveolar lavage (BAL) was performed to assess lung toxicity. The generated particles mostly were in the submicron size range with a significant number of nanometer-sized particles formed. The primary metals present in the fumes were Fe (72.5%) and Zn (26.3%). The addition of the anti-spatter spray and glue did affect particle size distribution when spot welding galvanized steel, whereas they had no effect on metal composition. Multiple VOCs (e.g., methyl methacrylate, acetaldehyde, ethanol, acetone, benzene, xylene) were identified when spot welding using either the glue or the anti-spatter spray that were not present when welding alone. Markers of lung injury (BAL lactate dehydrogenase) and inflammation (total BAL cells/neutrophils and cytokines/chemokines) were significantly elevated compared to controls 1 day after exposure to the spot welding fumes. The elevated pulmonary response was transient as lung toxicity mostly returned to control values by 7 days. The VOCs or the concentrations that they were generated during the animal exposures had no measurable effect on the pulmonary responses. Inhalation of galvanized spot welding fumes caused acute lung toxicity most likely due to the short-term exposure of particles that contain Zn.
Simoens, Ch; Deckelbaum, R J; Carpentier, Y A
2004-08-01
The present study aimed to determine whether including medium-chain fatty acids (MCFA) in specifically designed structured triglycerides (STG) with a MCFA in sn-1 and sn-3 positions and a long-chain (LC) FA in sn-2 position (MLM) would lead to different effects on plasma lipids and FA distribution into plasma and tissue lipids by comparison to a mixture of separate MCT and LCT molecules (MMM/LLL). The fatty acid (FA) composition was comparable in both lipid emulsions. Lipids were infused over 9h daily, in 2 groups of dogs (n = 6 each), for 28 days as a major component (55% of the non-protein energy intake) of total parenteral nutrition (TPN). Blood samples were obtained on specific days, before starting and just before stopping TPN. The concentration of plasma lipids was measured before starting and before stopping TPN on days 1, 2, 3, 4, 5, 8, 10, 12, 16 and 28. Biopsies were obtained from liver, muscle and adipose tissue 15 days before starting, and again on the day following cessation of TPN. In addition, the spleen was removed after the TPN period. FA composition in plasma and tissue lipids was analysed by gas liquid chromatography in different lipid components of plasma and tissues. No differences in either safety or tolerance parameters were detected between both lipid preparations. A lower rise of plasma TG (P < 0.05) was observed during MLM infusion, indicating a faster elimination rate of MLM vs MMM/LLL emulsion. In spite of the differences of TG molecules which would be assumed to affect the site of FA delivery and metabolic fate, FA distribution in phospholipids (PL) of hepatic and extrahepatic tissues did not substantially differ between both emulsions. Copyright 2003 Elsevier Ltd.
Qu, Han; Ma, Ruixue; Wang, Bin; Yang, Jian; Duan, Lei; Yu, Gang
2018-04-22
In present study, we investigated the enantioselective behaviors of the chiral antidepressant venlafaxine and its metabolite O-desmethylvenlafaxine in loach Misgurnus anguillicaudatus (M. anguillicaudatus), as well as effects of microplastic on toxicity, distribution and metabolism through a 40-day co-exposure. The contents of SOD and MDA in loach liver elevated when the loach was exposed to venlafaxine and O-desmethylvenlafaxine. Moreover, co-exposure with microplastic might lead to more adverse effect against loach. The distribution of venlafaxine and O-desmethylvenlafaxine were both detected in loach tissues and liver subcellular. The concentrations of venlafaxine and O-desmethylvenlafaxine were lower in water in microplastic-present treatment. Whilst, more contaminants were accumulated in liver through the "vehicle" (microplastic). Enantioselective behavior of venlafaxine and O-desmethylvenlafaxine occurred with R-enantiomers being preferentially degraded. With microplastic present, the bioaccumulation factor (BAF) of venlafaxine and O-desmethylvenlafaxine in loach tissue amplified more than 10 times. In liver subcellular structure, microplastic may help to transport more compounds into subtle areas and postpone the contaminants metabolism in organisms. The present study for the first time gained an insight into the potential ecological effects and environmental behaviors of combined pollutions of chiral pharmaceuticals and microplastic, which could supply important information for environment risk assessment of concurrent organic pollutants and microplastic. Copyright © 2018 Elsevier B.V. All rights reserved.
Morita, K; Matsueda, T; Iida, T
1997-05-01
This paper presents the liver distribution and fecal excretion of polychlorinated biphenyls (PCB), polychlorinated dibenzofurans (PCDF) congeners and polychlorinated dibenzo-p-dioxins (PCDD) congeners, in male rats fed with powdered green tea (matcha). The rats were given a treatment diet containing 10% matcha for the first five days. Then, the animals were administered 4 g of 10% matcha diet containing 0.5 ml of the casual rice-bran oil of Yusho that had occurred in the Southwest part of Japan in 1968 and kept on the same diet for another five days. The fecal excretion of PCB, PCDF and PCDD in the group fed with 10% matcha were 4.4, 2.4-9.1 and 2.5-4.7 times higher (p < 0.01), respectively, than that in the control group. The liver distribution of PCB, PCDF and PCDD in the same groups were 79%, 20-75% and 26-67% of the control group, respectively. These findings suggest that administration of matcha is useful as a treatment of Yusho patients exposed to PCB, PCDF and PCDD.
Airborne particulate matter and spacecraft internal environments
NASA Technical Reports Server (NTRS)
Liu, Benjamin Y. H.; Rubow, Kenneth L.; Mcmurry, Peter H.; Kotz, Thomas J.; Russo, Dane
1991-01-01
Instrumentation, consisting of a Shuttle Particle Sampler (SPS) and a Shuttle Particle Monitor (SPM), has been developed to characterize the airborne particulate matter in the Space Shuttle cabin during orbital flight. The SPS size selectively collects particles in four size fractions (0-2.5, 2.5-10, 10-100, and greater than 100 microns) which are analyzed postflight for mass concentration and size distribution, elemental composition, and morphology. The SPM provides a continuous record of particle concentration through photometric light scattering. Measurements were performed onboard Columbia, OV-102, during the flight of STS-32 in January 1990. No significant changes were observed in the particle mass concentration, size distribution, or chemical composition in samples collected during flight-day 2 and flight-day 7. The total mass concentration was 56 microg/cu cm with approximately half of the particles larger than 100 microns. Elemental analysis showed that roughly 70 percent of the particles larger than 2.5 microns were carbonaceous with small amounts of other elements present. The SPM showed no temporal or spatial variation in particle mass concentration during the mission.
Genital herpes simplex virus infections: clinical manifestations, course, and complications.
Corey, L; Adams, H G; Brown, Z A; Holmes, K K
1983-06-01
The clinical course and complications of 268 patients with first episodes and 362 with recurrent episodes of genital herpes infection were reviewed. Symptoms of genital herpes were more severe in women than in men. Primary first-episode genital herpes was accompanied by systemic symptoms (67%), local pain and itching (98%), dysuria (63%), and tender adenopathy (80%). Patients presented with several bilaterally distributed postular ulcerative lesions that lasted a mean of 19.0 days. Herpes simplex virus was isolated from the urethra, cervix, and pharynx of 82%, 88%, and 13% of women with first-episode primary genital herpes, and the urethra and pharynx of 28% and 7% of men. Complications included aseptic meningitis (8%), sacral autonomic nervous system dysfunction (2%), development of extragenital lesions (20%), and secondary yeast infections (11%). Recurrent episodes were characterized by small vesicular or ulcerative unilaterally distributed lesions that lasted a mean of 10.1 days. Systemic symptoms were uncommon and 25% of recurrent episodes were asymptomatic. The major concerns of patients were the frequency of recurrences and fear of transmitting infection to partners or infants.
NASA Astrophysics Data System (ADS)
Mano, T.; Guo, X.; Fujii, N.; Yoshie, N.; Takeoka, H.
2016-02-01
Jellyfishes often form dense aggregation that causes a variety of social problems such as clogging seawater intake of power plant, breaking fisheries net and more. Understanding on jellyfish aggregation is not sufficient due to the difficulty of observation on this phenomenon. In this study, high-resolution observations using scientific echo sounder and underwater camera were carried out to reveal the fine structure of moon jellyfish distribution in a 3D space, as well as its abundance and temporal variation. In addition, water temperature, salinity and current speed were also measured for inferring formation mechanisms of jellyfish aggregation. The field observations with a target on moon jellyfish were carried out in August 2013 and August 2014, in a semi-enclosed bay in Japan. The ship equipped with scientific echo sounder was cruised over the entire bay to reveal the distribution and the form of the moon jellyfish aggregation. In August 2013, the jellyfish aggregations present a high density (maximum: 70 ind. /m3) and their outline shows spherical or zonal shape with a hollow structure. In August 2014, the jellyfish aggregations present a low density (maximum: 20 ind./m3) and the jellyfishes distributed in a layer structure over a wide area. The depth of jellyfish aggregation was consistent with thermocline. During three days of observations in 2014, the average population density of jellyfish reduced by one-tenth, showing a possibility that the jellyfish abundance in a bay may vary significantly in a short timescale of several days. Not only the active swimming of jellyfishes but also the ambient flow field associated with internal waves or Langmuir circulation may contribute to the jellyfish aggregations. In order to clarify the mechanisms for the formation of high density patchy aggregation, we plan to perform more detailed observations and numerical simulations that are able to capture the fine structure of these physical processes in the future.
Ramos, Ana Carolina Simões; Lemos-Filho, José Pires; Ribeiro, Renata Acácio; Santos, Fabrício Rodrigues; Lovato, Maria Bernadete
2007-01-01
Background and Aims Hymenaea stigonocarpa (Fabaceae: Caesalpinioideae) is an endemic tree from the Brazilian cerrado (savanna vegetation), a biome classified as a hotspot for conservation priority. This study investigates the phylogeographic structure of H. stigonocarpa, in order to understand the processes that have led to its current spatial genetic pattern. Methods The polymorphism level and spatial distribution of variants of the plastid non-coding region between the genes psbC and trnS were investigated in 175 individuals from 17 populations, covering the greater part of the total distribution of the species. Molecular diversity indices were calculated and intra-specific relationships were inferred by the construction of haplotype networks using the median-joining method. Genetic differentiation among populations and main geographical groups was evaluated using spatial analysis of molecular variance (SAMOVA). Key Results Twenty-three different haplotypes were identified. The level of differentiation among the populations analysed was relatively high (FST = 0·692). Phylogeographic analyses showed a clear association between the haplotype network and geographic distribution of populations, revealing three main geographical groups: western, central and eastern. SAMOVA corroborated this finding, indicating that most of the variation can be attributed to differences among these three groups (58·8 %), with little difference among populations within groups (FSC = 0·252). Conclusions The subdivision of the geographic distribution of H. stigonocarpa populations into three genetically differentiated groups can be associated with Quaternary climatic changes. The data suggest that during glacial times H. stigonocarpa populations became extinct in most parts of the southern present-day cerrado area. Milder climatic conditions in the north and eastern portions of the cerrado resulted in maintenance of populations in these regions. Thus it is inferred that the most southern part of the present-day cerrado was re-colonized by different lineages from northern parts of this biome, after postglacial climate amelioration. PMID:17881340
Huang, Yi-Min; Liu, Zi-Rui; Chen, Hong; Wang, Yue-Si
2013-04-01
To investigate the size distribution characteristics of water soluble inorganic ions in haze days, the particle samples were collected by two Andersen cascade impactors in Beijing during summer and winter time and each sampling period lasted two weeks. Online measurement of PM10 and PM2.5 using TEOM were also conducted at the same time. Sources and formation mechanism of water soluble inorganic ions were analyzed based on their size distributions. The results showed that average concentrations of PM10 and PM 2.5 were (245.5 +/- 8.4) microg x m(-3) and (120.2 +/- 2.0) microg x m(-3) during summer haze days (SHD), and were (384.2 +/- 30.2) microg x m(-3) and (252.7 +/- 47.1) microg x m(-3) during winter haze days (WHD), which suggested fine particles predominated haze pollution episode in both seasons. Total water-soluble inorganic ions concentrations were higher in haze days than those in non-haze days, especially in fine particles. Furthermore, concentrations of secondary inorganic ions (SO4(2-), NO3(-) and NH4(+)) increased quicker than other inorganic ions in fine particles during haze days, indicating secondary inorganic ions played an important role in the formation of haze pollution. Similar size distributions were found for all Sinorganic water soluble ions except for NO3(-), during SHD and WHD. SO4(2-) and NH4(+) dominated in the fine mode (PM1.0) while Mg2+ and Ca2+ accumulated in coarse fraction, Na+, Cl- and K+ showed a bimodal distribution. For NO3(-), however, it showed a bimodal distribution during SHD and a unimodal distribution dominated in the fine fraction was found during WHD. The average mass median aerodynamic diameter (MMAD) of SO4(2-) was 0.64 microm in SHD, which suggested the formation of SO4(2-) was mainly attributed to in-cloud processes. Furthermore, a higher apparent conversion rate of sulfur dioxide (SOR) was found in SHD, indicating more fine particles were produced by photochemical reaction in haze days than that in non-haze days. The MMAD of SO4(2-) increased to 0.89 microm in WHD, local emission of SO2 and the subsequently heterogeneous reaction became the main source of SO4(2-) during winter time. The average MMADs of NO3(-) were 2.85 microm and 0.80 microm in SHD and WHD, respectively. Influenced by the seasonal temperature difference, NO3(-) mainly existed in the form of calcium nitrate in coarse mode during SHD while the fine mode nitrate was associated with ammonium during WHD.
NASA Technical Reports Server (NTRS)
Hammerling, Dorit M.; Michalak, Anna M.; Kawa, S. Randolph
2012-01-01
Satellite observations of CO2 offer new opportunities to improve our understanding of the global carbon cycle. Using such observations to infer global maps of atmospheric CO2 and their associated uncertainties can provide key information about the distribution and dynamic behavior of CO2, through comparison to atmospheric CO2 distributions predicted from biospheric, oceanic, or fossil fuel flux emissions estimates coupled with atmospheric transport models. Ideally, these maps should be at temporal resolutions that are short enough to represent and capture the synoptic dynamics of atmospheric CO2. This study presents a geostatistical method that accomplishes this goal. The method can extract information about the spatial covariance structure of the CO2 field from the available CO2 retrievals, yields full coverage (Level 3) maps at high spatial resolutions, and provides estimates of the uncertainties associated with these maps. The method does not require information about CO2 fluxes or atmospheric transport, such that the Level 3 maps are informed entirely by available retrievals. The approach is assessed by investigating its performance using synthetic OCO-2 data generated from the PCTM/ GEOS-4/CASA-GFED model, for time periods ranging from 1 to 16 days and a target spatial resolution of 1deg latitude x 1.25deg longitude. Results show that global CO2 fields from OCO-2 observations can be predicted well at surprisingly high temporal resolutions. Even one-day Level 3 maps reproduce the large-scale features of the atmospheric CO2 distribution, and yield realistic uncertainty bounds. Temporal resolutions of two to four days result in the best performance for a wide range of investigated scenarios, providing maps at an order of magnitude higher temporal resolution relative to the monthly or seasonal Level 3 maps typically reported in the literature.
Higuchi, Yukito
2016-01-01
Studies on growth hormone therapy in children have shown that height velocity is greater in summer than in winter and that this difference increases with latitude. It is hypothesized that summer daylight is a causative factor and that geographical distribution of body height will approximate the distribution of summer day length over time. This is an ecological analysis of prefecture-level data on the height of Japanese youth. Mesh climatic data of effective day length were collated. While height velocity was greatest during the summer, the height of Japanese youth was strongly and negatively correlated with the distribution of winter effective day length. Therefore, it is anticipated that summer height velocity is greater according to winter day length (dark period). This may be due to epigenetic modifications, involving reversible DNA methylation and thyroid hormone regulation found in the reproductive system of seasonal breeding vertebrates. If the function is applicable to humans, summer height growth may quantitatively increase with winter day length, and height growth seasonality can be explained by thyroid hormone activities that-induced by DNA methylation-change depending on the seasonal difference in day length. Moreover, geographical differences in body height may be caused by geographical differences in effective day length, which could influence melatonin secretion among subjects who spend a significant time indoors.
ERIC Educational Resources Information Center
Broyles, Iris A.
2011-01-01
This study evaluated the effectiveness of a distributed cognition hybrid minicourse in increasing a 1-day camp's ability to effect long-term knowledge retention and pro-environment attitudes and behaviors in sixth graders. The preevent-postevent minicourse was designed to reduce cognitive overload generated by an intense immersion into the…
Trading strategies for distribution company with stochastic distributed energy resources
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, Chunyu; Wang, Qi; Wang, Jianhui
2016-09-01
This paper proposes a methodology to address the trading strategies of a proactive distribution company (PDISCO) engaged in the transmission-level (TL) markets. A one-leader multi-follower bilevel model is presented to formulate the gaming framework between the PDISCO and markets. The lower-level (LL) problems include the TL day-ahead market and scenario-based real-time markets, respectively with the objectives of maximizing social welfare and minimizing operation cost. The upper-level (UL) problem is to maximize the PDISCO’s profit across these markets. The PDISCO’s strategic offers/bids interactively influence the outcomes of each market. Since the LL problems are linear and convex, while the UL problemmore » is non-linear and non-convex, an equivalent primal–dual approach is used to reformulate this bilevel model to a solvable mathematical program with equilibrium constraints (MPEC). The effectiveness of the proposed model is verified by case studies.« less
Space Weather Studies Using the Low-Latitude Ionospheric Sensor Network (LISN)
NASA Astrophysics Data System (ADS)
Valladares, C. E.; Pacheco, E.
2014-12-01
LISN is an array of small instruments that operates as a real-time distributed observatory to understand the complex day-to-day variability and the extreme state of disturbance that occurs in the South American low-latitude ionosphere nearly every day after sunset. The LISN observatory aims to forecast the initiation and transport of plasma bubbles across the South American continent. The occurrence of this type of plasma structures and their embedded irregularities poses a prominent natural hazard to communication, navigation and high precision pointing systems. As commercial and military aviation is increasingly reliant on Global Navigation Satellite Systems (GNSS) any interruption due to ionospheric irregularities or errors due to large density gradients constitutes a serious threat to passengers and crew. Therefore, it is important to understand the conditions and sources that contribute to the formation of these irregularities. To achieve high quality regional nowcasts and forecasts, the LISN system was designed to include a dense coverage of the South American landmass with 47 GPS receivers, 5 flux-gate magnetometers distributed on 2 base lines and 3 Vertical Incidence Pulsed Ionospheric Radar (VIPIR) ionosondes deployed along the same magnetic meridian that intersects the magnetic equator at 68° W. This presentation will provide a summary of recent instrument installations and new processing techniques that have been developed under the LISN project. We will also present the results of recent efforts to detect TIDs and TEC plasma depletions on a near real-time basis. We will describe a method to estimate the zonal velocity and tilt of the plasma bubbles/depletions by combining observations of TEC depletions acquired with adjacent receivers, making it possible to predict precisely their future locations.
Prestele, Reinhard; Hirsch, Annette L; Davin, Edouard L; Seneviratne, Sonia I; Verburg, Peter H
2018-05-10
Conservation agriculture (CA) is widely promoted as a sustainable agricultural management strategy with the potential to alleviate some of the adverse effects of modern, industrial agriculture such as large-scale soil erosion, nutrient leaching and overexploitation of water resources. Moreover, agricultural land managed under CA is proposed to contribute to climate change mitigation and adaptation through reduced emission of greenhouse gases, increased solar radiation reflection, and the sustainable use of soil and water resources. Due to the lack of official reporting schemes, the amount of agricultural land managed under CA systems is uncertain and spatially explicit information about the distribution of CA required for various modeling studies is missing. Here, we present an approach to downscale present-day national-level estimates of CA to a 5 arcminute regular grid, based on multicriteria analysis. We provide a best estimate of CA distribution and an uncertainty range in the form of a low and high estimate of CA distribution, reflecting the inconsistency in CA definitions. We also design two scenarios of the potential future development of CA combining present-day data and an assessment of the potential for implementation using biophysical and socioeconomic factors. By our estimates, 122-215 Mha or 9%-15% of global arable land is currently managed under CA systems. The lower end of the range represents CA as an integrated system of permanent no-tillage, crop residue management and crop rotations, while the high estimate includes a wider range of areas primarily devoted to temporary no-tillage or reduced tillage operations. Our scenario analysis suggests a future potential of CA in the range of 533-1130 Mha (38%-81% of global arable land). Our estimates can be used in various ecosystem modeling applications and are expected to help identifying more realistic climate mitigation and adaptation potentials of agricultural practices. © 2018 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.
Aerosol and CCN in southwest Saudi Arabia
NASA Astrophysics Data System (ADS)
Collins, Don; Li, Runjun; Axisa, Duncan; Kucera, Paul; Burger, Roelof
2010-05-01
As part of an ongoing study of the microphysical and dynamical controls on precipitation in southwest Saudi Arabia, a number of surface and aircraft-based instruments were used in summer / fall 2009 to measure the size distribution, hygroscopic properties, and cloud droplet nucleation efficiency of the local aerosol. Submicron size distributions were measured using differential mobility analyzers both on the ground and on board the aircraft, while an aerodynamic particle sizer and a forward scattering spectrometer probe were used to measure the supermicron size distributions on the ground and from on board the aircraft, respectively. Identical continuous flow cloud condensation nuclei counters were used to measure CCN spectra at the surface and aloft and a humidified tandem differential mobility analyzer was operated on the ground to measure size-resolved hygroscopicity. The aerosol in this arid environment is characterized by a persistent accumulation mode having hygroscopic and CCN efficiency properties consistent with a sulfate-rich aged aerosol. The particles in that background aerosol are generally sufficiently large and hygroscopic to activate at those supersaturations expected in the convective clouds responsible for most of the regional precipitation, which consequently acts as a lower bound on the resulting cloud droplet concentrations. Though the concentration, size distribution, and properties of the submicron aerosol generally changed very slowly over periods of several hours, abrupt ~doubling in concentration almost always accompanied the arrival of the sea breeze front that began along the Red Sea. Interestingly, the hygroscopicity and the shape of the size distribution differed little in the pre- and post-sea breeze air masses. The dust-dominated coarse mode typically contributed significantly more to the aerosol mass concentration than did the submicron mode and likely controlled the ice nuclei concentration, though no direct measurements were made to confirm this. Results of routine flight patterns designed to examine the spatial, vertical, and day-to-day variability of the aerosol will be presented and the link between the aerosol at the surface and aloft will be quantified. This presentation will emphasize the regional character of the aerosol and will assess its influence on cloud microphysics.
Endometrial biopsy in Holstein-Friesian dairy cows. I. Technique, histological criteria and results.
Bonnett, B N; Miller, R B; Etherington, W G; Martin, S W; Johnson, W H
1991-01-01
Endometrial biopsies were taken for histological assessment from 97 cows which calved in a commercial dairy herd between April and August 1984. Sixty-two cows were biopsied at both day 26 and 40 postpartum, 23 cows at only day 26, and 12 at day 40 only. Subjective and quantitative histological criteria were assessed. Ninety-five percent of biopsies were adequate for at least subjective assessment. The distribution of criteria within each horn-day category, as well as combined readings by day and by gravid or nongravid horn were computed and significant differences noted. There was more severe inflammation and more segmented cells at day 26 than 40 postpartum, and in the gravid compared to the nongravid horn. The distribution patterns for the criteria examined provide an overview of histological characteristics in this group of postpartum cows. PMID:1884295
Dietary Protein Intake and Distribution Patterns of Well-Trained Dutch Athletes.
Gillen, Jenna B; Trommelen, Jorn; Wardenaar, Floris C; Brinkmans, Naomi Y J; Versteegen, Joline J; Jonvik, Kristin L; Kapp, Christoph; de Vries, Jeanne; van den Borne, Joost J G C; Gibala, Martin J; van Loon, Luc J C
2017-04-01
Dietary protein intake should be optimized in all athletes to ensure proper recovery and enhance the skeletal muscle adaptive response to exercise training. In addition to total protein intake, the use of specific proteincontaining food sources and the distribution of protein throughout the day are relevant for optimizing protein intake in athletes. In the present study, we examined the daily intake and distribution of various proteincontaining food sources in a large cohort of strength, endurance and team-sport athletes. Well-trained male (n=327) and female (n=226) athletes completed multiple web-based 24-hr dietary recalls over a 2-4 wk period. Total energy intake, the contribution of animal- and plant-based proteins to daily protein intake, and protein intake at six eating moments were determined. Daily protein intake averaged 108±33 and 90±24 g in men and women, respectively, which corresponded to relative intakes of 1.5±0.4 and 1.4±0.4 g/kg. Dietary protein intake was correlated with total energy intake in strength (r=0.71, p <.001), endurance (r=0.79, p <.001) and team-sport (r=0.77, p <.001) athletes. Animal and plant-based sources of protein intake was 57% and 43%, respectively. The distribution of protein intake was 19% (19±8 g) at breakfast, 24% (25±13 g) at lunch and 38% (38±15 g) at dinner. Protein intake was below the recommended 20 g for 58% of athletes at breakfast, 36% at lunch and 8% at dinner. In summary, this survey of athletes revealed they habitually consume > 1.2 g protein/kg/d, but the distribution throughout the day may be suboptimal to maximize the skeletal muscle adaptive response to training.
Gastroenterology training in a resource-limited setting: Zambia, Southern Africa
Asombang, Akwi W; Turner-Moss, Eleanor; Seetharam, Anil; Kelly, Paul
2013-01-01
AIM: To evaluate need for and efficacy of a structured gastroenterology didactic session in expanding awareness and understanding of digestive disorders. METHODS: A four-day symposium was developed with didactic sessions (days 1, 2) and practical endoscopy (days 3, 4). Didactic sessions included case presentations highlighting pathophysiology and management. One nurse and four practicing gastroenterologists from the United Kingdom led lectures and supervised workshops with audience participation. Practical endoscopy focused on diagnostic and therapeutic procedures and their application to diagnosis and treatment of ailments of the gastrointestinal tract. Pre- and post-workshop questionnaires were distributed to participants during didactic sessions. A pre-workshop questionnaire gauged expectations and identified objectives to be met at the symposium. Post-workshop questionnaires were administered to assess efficacy of each session. Participants graded sessions from 1 (poor) to 5 (excellent) on quality of case presentations, knowledge, clarity and mode of presentation. We assessed if time allotted to each topic was sufficient, value of sessions, impact on practice and interest in future symposiums. RESULTS: There were 46 attendees on day 1: 41% undergraduates, 41% residents, 11% consultants and 4% unspecified. Day 2 (a Saturday) had 24 participants: 17% undergraduates, 71% residents, 9% consultants, 4% unspecified. Primary pre-workshop symposium expectation was to gain knowledge in: general gastroenterology (55.5%), practical endoscopy (13.8%), pediatric gastroenterology (5%), epidemiology of gastrointestinal disorders specific to Zambia (6%), and interaction with international speakers (6%). The post-symposium questionnaire was answered by 19 participants, of whom 95% felt specific aims were met; all would attend future conferences and recommend to others. CONCLUSION: The beneficial effect of a structured symposium in developing countries warrants further attention as a mechanism to improve disease awareness in areas where resources are limited. PMID:23840144
Gastroenterology training in a resource-limited setting: Zambia, Southern Africa.
Asombang, Akwi W; Turner-Moss, Eleanor; Seetharam, Anil; Kelly, Paul
2013-07-07
To evaluate need for and efficacy of a structured gastroenterology didactic session in expanding awareness and understanding of digestive disorders. A four-day symposium was developed with didactic sessions (days 1, 2) and practical endoscopy (days 3, 4). Didactic sessions included case presentations highlighting pathophysiology and management. One nurse and four practicing gastroenterologists from the United Kingdom led lectures and supervised workshops with audience participation. Practical endoscopy focused on diagnostic and therapeutic procedures and their application to diagnosis and treatment of ailments of the gastrointestinal tract. Pre- and post-workshop questionnaires were distributed to participants during didactic sessions. A pre-workshop questionnaire gauged expectations and identified objectives to be met at the symposium. Post-workshop questionnaires were administered to assess efficacy of each session. Participants graded sessions from 1 (poor) to 5 (excellent) on quality of case presentations, knowledge, clarity and mode of presentation. We assessed if time allotted to each topic was sufficient, value of sessions, impact on practice and interest in future symposiums. There were 46 attendees on day 1: 41% undergraduates, 41% residents, 11% consultants and 4% unspecified. Day 2 (a Saturday) had 24 participants: 17% undergraduates, 71% residents, 9% consultants, 4% unspecified. Primary pre-workshop symposium expectation was to gain knowledge in: general gastroenterology (55.5%), practical endoscopy (13.8%), pediatric gastroenterology (5%), epidemiology of gastrointestinal disorders specific to Zambia (6%), and interaction with international speakers (6%). The post-symposium questionnaire was answered by 19 participants, of whom 95% felt specific aims were met; all would attend future conferences and recommend to others. The beneficial effect of a structured symposium in developing countries warrants further attention as a mechanism to improve disease awareness in areas where resources are limited.
Color associations for days and letters across different languages
Rouw, Romke; Case, Laura; Gosavi, Radhika; Ramachandran, Vilayanur
2014-01-01
While colors are commonplace in everyday metaphors, relatively little is known about implicit color associations to linguistic or semantic concepts in a general population. In this study, we test color associations for ordered linguistic concepts (letters and days). The culture and language specificity of these effects was examined in a large group (457) of Dutch-speaking participants, 92 English-speaking participants, and 49 Hindi-speaking participants. Non-random distributions of color choices were revealed; consistencies were found across the three language groups in color preferences for both days and letters. Interestingly, while the Hindi-speaking participants were presented with letter stimuli matched on phonology, their pattern of letter-to-color preferences still showed similarities with Dutch- and English-speaking participants. Furthermore, we found that that the color preferences corresponded between participants indicating to have conscious color experiences with letters or days (putative synesthetes) and participants who do not (non-synesthetes). We also explored possible mechanisms underlying the color preferences. There were a few specific associations, including red for “A,” red for “Monday,” and white for “Sunday.” We also explored more general mechanisms, such as overall color preferences as shown by Simner et al. (2005). While certainly not all variation can be explained or predicted, the results show that regularities are present in color-to-letter or color-to-day preferences in both putative synesthetes and non-synesthetes across languages. Both letter-to-color and day-to-color preferences were influenced by multiple factors. The findings support a notion of abstract concepts (such as days and letters) that are not represented in isolation, but are connected to perceptual representational systems. Interestingly, at least some of these connections to color representations are shared across different language/cultural groups. PMID:24904447
[Contact allergy caused by poison ivy (Toxicodendron spp].
Fölster-Holst, R; Hausen, B M; Brasch, J; Christophers, E
2001-02-01
Within 3 days two female patients presented with an eruption featuring erythema, edema, vesicles and bullae. We suspected poison ivy allergy which was subsequently proven by history and positive patch tests. In Germany the risk of specific hypersensitivity to Toxicodendron species is low, since the distribution of such plants is confined to botanical gardens. Other species belonging to the family of Anacardiaceae contain urushiols as well (e.g., mango, cashew) and may cause allergic contact dermatitis.
The Potential for Collocated AGLP and ERBE data for Fire, Smoke, and Radiation Budget Studies
NASA Technical Reports Server (NTRS)
Christropher, S. A.; Chou, J.
1997-01-01
One month of the Advanced Very High Resolution Radiometer (AVHRR) Global Area Coverage (GAC) Land Pathfinder (AGLP) data from September 1985 are used to examine the spatial and temporal distribution of fires over four major ecosystems in South America. The Earth Radiation Budget Experiment (ERBE) scanner data are used to examine the top of atmosphere (TOA) shortwave and longwave fluxes over smoke generated from biomass burn- ing. The relationship between the AGLP-derived Normalized Difference Vegetation Index (NDVI) and the ERBE-estimated clear sky albedos are also examined as a function of the four ecosystems. This study shows that the grassland areas in South America have the highest number of fires for September 1985, and their corresponding NDVI values are smaller than the tropical rainforest region where the number of fires were comparatively small. Clear sky statistics accumulated during the days when smoke was not present show that clear sky albedos derived from ERBE are higher for grassland areas when compared to the tropical rainforest. The results show that the AGLP can be used to determine the spatial and temporal distribution of fires along with vegetation characteristics, while ERBE data can provide necessary information on broadband albedos and regional top of atmosphere radiative impacts of biomass burning aerosols. Since the AGLP data are available from 1981 to the present day, several climate-related issues can be addressed.
The Potential for Collocated AGLP and ERBE Data for Fire, Smoke, and Radiation Budget Studies
NASA Technical Reports Server (NTRS)
Christopher, S. A.; Chou, J.
1997-01-01
One month of the Advanced Very High Resolution Radiometer (AVHRR) Global Area Coverage (GAC) Land Pathfinder (AGLP) data from September 1985 are used to examine the spatial and temporal distribution of fires over four major ecosystems in South America. The Earth Radiation Budget Experiment (ERBE) scanner data are used to examine the top of atmosphere (TOA) shortwave and longwave fluxes over smoke generated from biomass burning. The relationship between the AGLP-derived Normalized Difference Vegetation Index (NDVI) and the ERBE-estimated clear sky albedos are also examined as a function of the four ecosystems. This study shows that the grassland areas in South America have the highest number of tires for September 1985, and their corresponding NDVI values are smaller than the tropical rainforest region where the number of fires were comparatively small. Clear sky statistics accumulated during the days when smoke was not present show that clear sky albedos derived from ERBE are higher for grassland areas when compared to the tropical rainforest. The results show that the AGLP can be used to determine the spatial and temporal distribution of fires along with vegetation characteristics, while ERBE data can provide necessary information on broadband albedos and regional top of atmosphere radiative impacts of biomass burning aerosols. Since the AGLP data are available from 1981 to the present day, several climate-related issues can be addressed.
The Potential for Collocated AGLP and ERBE Data for Fire, Smoke, and Radiation Budget Studies
NASA Technical Reports Server (NTRS)
Christopher, S. A.; Chou, J.
1997-01-01
One month of the Advanced Very High Resolution Radiometer (AVHRR) Global Area Coverage (GAC) Land Pathfinder (AGLP) data from September 1985 are used to examine the spatial and temporal distribution of fires over four major ecosystems in South America. The Earth Radiation Budget Experiment (ERBE) scanner data are used to examine the top of atmosphere (TOA) shortwave and longwave fluxes over smoke generated from biomass burning. The relationship between the AGLP-derived Normalized Difference Vegetation Index (NDVI) and the ERBE-estimated clear sky albedos are also examined as a function of the four ecosystems. This study shows that the grassland areas in South America have the highest number of fires for September 1985. and their corresponding NDVI values are smaller than the tropical rainforest region where the number of fires were comparatively small. Clear sky statistics accumulated during the days when smoke was not present show that clear sky albedos derived from ERBE are higher for grassland areas when compared to the tropical rainforest. The results show that the AGLP can be used to determine the spatial and temporal distribution of fires along with vegetation characteristics, while ERBE data can provide necessary information on broadband albedos and regional top of atmosphere radiative impacts of biomass burning aerosols. Since the AGLP data are available from 1981 to the present day, several climate-related issues can be addressed,
Green, J; Kellogg, T; Keirs, R; Cooper, R
1987-11-01
A bile acid analogue, SEHCAT (tauro-23-75SE-selena-homocholic acid), was used to determine bile acid pool size, turnover time, and distribution in the developing broiler chick. Bile acid pool size was significantly affected by age and followed a quintic trend (a fifth degree polynomial). It remained steady until 30 days of age when it decreased significantly and then rose significantly at 37 days of age. The bile acid pool half-life remained constant until 28 days of age when it increased significantly and then held steady until it increased again at 8 wk of age following a quartic trend. The distribution of bile acids was affected by age with the amount in the gizzard, duodenum, cloaca, liver, and gall bladder varying significantly with age. Jejunal, ileal, and cecal bile acids did not vary significantly with age. Liver bile acid levels followed a quintic trend, rising until 23 days of age and dropping sharply at 30 days of age and holding steady.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Greenlaw, P.D.; Minick, S.K.
This Quality Assessment Program (QAP) is designed to test the quality of the environmental measurements being reported to the Department of Energy by its contractors. Since 1976, real or synthetic environmental samples that have been prepared and thoroughly analyzed at the Environmental Measurements Laboratory (EML) have been distributed at first quarterly and then semi-annually to these contractors. Their results, which are returned to EML within 90 days, are compiled with EML`s results and are reported back to the participating contractors 30 days later. This report presents the results from the analysis of the 48th set of environmental quality assessment samplesmore » (QAP XLVIII) that were received on or before June 1, 1998.« less
Van Heteren, S.; FitzGerald, D.M.; Barber, D.C.; Kelley, J.T.; Belknap, D.F.
1996-01-01
Ground-penetrating-radar (GPR) profiles calibrated with core data allow accurate assessments of coastal barrier volumes. We applied this procedure successfully to the barrier system along Saco Bay, Maine (USA), as part of a sediment-budget study that focused on present-day sand volumes in various coastal, shoreface, and inner-shelf lith-osomes, and on sand fluxes that have affected the volume or distribution of sand in these sediment bodies through time. On GPR profiles, the components of the barrier lithosome are readily differentiated from other facies, except where the radar signal is attenuated by brackish or salty groundwater. Significant differences between dielectric properties of the barrier lithosome and other units commonly result in strong boundary reflectors. The mostly sandy barrier sediments allow deep penetration of GPR waves, in contrast to finer-grained strata and till-covered bedrock. Within the Saco Bay barrier system, 22 ??3 x 106 m3 of sediment are unevenly distributed. Two-thirds of the total barrier volume is contained within the northern and southern ends of the study area, in the Pine Point spit and the Ferry Beach/Goosefare complex, respectively. The central area around Old Orchard Beach is locally covered by only a thin veneer of barrier sand, averaging <3 m, that unconformably overlies shallow pre-Holocene facies. The prominence of barrier-spit facies and the distribution pattern of back-barrier sediments indicate that a high degree of segmentation, governed by antecedent topography, has affected the development of the Saco Bay barrier system. The present-day configuration of the barrier and back-barrier region along Saco Bay, however, conceals much of its early compartmentalized character.
NASA Astrophysics Data System (ADS)
Nambu, Ryogen; Saito, Hajime; Tanaka, Yoshio; Higano, Junya; Kuwahara, Hisami
2012-03-01
There are many studies on spatial distributions of Asari clam Ruditapes philippinarum adults on tidal flats but few have dealt with spatial distributions of newly settled Asari clam (<0.3 mm shell length, indicative of settlement patterns) in relation to physical/topographical conditions on tidal flats. We examined small-scale spatial distributions of newly settled individuals on the Matsunase tidal flat, central Japan, during the low spring tides on two days 29th-30th June 2007, together with the shear stress from waves and currents on the flat. The characteristics of spatial distribution of newly settled Asari clam markedly varied depending on both of hydrodynamic and topographical conditions on the tidal flat. Using generalized linear models (GLMs), factors responsible for affecting newly settled Asari clam density and its spatial distribution were distinguished between sampling days, with "crest" sites always having a negative influence each on the density and the distribution on both sampling days. The continuously recorded data for the wave-current flows at the "crest" site on the tidal flat showed that newly settled Asari clam, as well as bottom sediment particles, at the "crest" site to be easily displaced. Small-scale spatial distributions of newly settled Asari clam changed with more advanced benthic stages in relation to the wave shear stress.
Ameliorative effect of vitamin C against hepatotoxicity induced by emamectin benzoate in rats.
Khaldoun Oularbi, H; Richeval, C; Lebaili, N; Zerrouki-Daoudi, N; Baha, M; Djennas, N; Allorge, D
2017-07-01
In the present study, we aimed to assess the potential protective effect of ascorbic acid (AA) against emamectin benzoate (EMB)-induced hepatotoxicity. For this purpose, biochemical, histopathological and analytical investigations were performed. Male Wistar rats were distributed into three groups, that is, a control group, an EMB group given 10 mg EMB/kg body weight (BW) by gavage and an EMB + AA group given 10 mg EMB/kg BW and vitamin C intraperitoneally (200 mg/kg). The duration of the treatment was 28 days and the duration of the study was 42 days. There was a statistically significant increase of all hepatic biomarkers, that is, aspartate aminotransferase, alanine aminotransferase and gamma-glutamyltransferase activities, and glycemia, in EMB-treated group when compared with the control group. Light microscopic observations revealed variable signs of hepatotoxicity in the EMB group, which were represented by alteration of normal hepatic architecture, inflammatory cell infiltration, hepatocellular steatosis and foci of necrosis at 28 and 42 days post-treatment. However, co-treatment with vitamin C reduced EMB-related liver toxicity and diminished the abnormal biochemical and architectural damage. Emamectin B1a and B1b residues were detectable in all plasma samples of treated rats at 14, 21 and 28 days of treatment. The drug liver tissue concentration was significantly lower in EMB + AA group compared with EMB group at 28 and 42 days. In conclusion, the findings of the present study clearly indicate a significant protective action of vitamin C against EMB hepatotoxicity.
Boyle, Kevin J; Paterson, Robert; Carson, Richard; Leggett, Christopher; Kanninen, Barbara; Molenar, John; Neumann, James
2016-05-15
Environmental regulations often have the objective of eliminating the lower tail of an index of environmental quality. That part of the distribution of environmental quality moves somewhere above a threshold and where in the original distribution it moves is a function of the control strategy chosen. This paper provides an approach for estimating the economic benefits of different distributional changes as the worst environmental conditions are removed. The proposed approach is illustrated by examining shifts in visibility at Class I visibility areas (National Parks and wilderness areas) that would occur with implementation of the U.S. Environmental Protection Agency's Regional Haze Program. In this application we show that people value shifts in the distribution of visibility and place a higher value on the removal of a low visibility day than on the addition of a high visibility day. We found that respondents would pay about $120 per year in the Southeast U.S. and about $80 per year in the Southwest U.S. for improvement programs that remove the 20% worst visibility days. Copyright © 2016 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Pi, X.; Vergados, P.
2017-12-01
GPS data from more than 2000 globally distributed ground-based stations are processed to generate Global Map of Ionospheric Irregularities and Scintillation (GMIIS) at 5-minite cadence for the 2015 St. Patrick's Day Storm. The time sequence of GMIIS provides global snapshots of evolving ionospheric irregularities that are helpful in investigations of small-scale ionospheric perturbations globally. Such data from selected stations at longitudes distributed around the globe are also analyzed to investigate longitudinal variations of low-latitude ionospheric irregularities (LLII) during the storm. Prior to the storm day, The GPS data show typical seasonal (March equinox) activities of LLII during evening hours in different longitude regions, i.e., active in American through Asian longitudes but relatively inactive in the Pacific sector. The data also reveal dramatic changes in LLII during the storm main phase (17 March 2015) and recovery phase (18-19 March 2015). While remaining inactive in the Pacific region, LLII have gone through complicated variations in the longitude regions of high scintillation season. The variations include active, weakened or suppressed, or post-midnight triggering during the storm main phase and recovery phase depending on specific longitude. To understand possible responsible causes of these variations in different longitudes, the Global Assimilative Ionospheric Model (GAIM) is used to reproduce ambient ionospheric state and its disturbances. For this storm study, GAIM assimilates GPS data from about 650 globally distributed stations and from spaceborne receivers onboard the COSMIC satellites. The global assimilative modeling enables us to investigate the changes of the equatorial ionospheric anomaly (EIA) and corresponding ionospheric dynamical processes in the concerned longitudes. This presentation will combine pictures of small- and large-scale ionospheric perturbations and attempt to obtain insight into mechanisms that drive LLII changes during the major storm.
NASA Astrophysics Data System (ADS)
Xie, Zhipeng; Hu, Zeyong; Xie, Zhenghui; Jia, Binghao; Sun, Genhou; Du, Yizhen; Song, Haiqing
2018-02-01
This paper presents the impact of two snow cover schemes (NY07 and SL12) in the Community Land Model version 4.5 (CLM4.5) on the snow distribution and surface energy budget over the Tibetan Plateau. The simulated snow cover fraction (SCF), snow depth, and snow cover days were evaluated against in situ snow depth observations and a satellite-based snow cover product and snow depth dataset. The results show that the SL12 scheme, which considers snow accumulation and snowmelt processes separately, has a higher overall accuracy (81.8%) than the NY07 (75.8%). The newer scheme performs better in the prediction of overall accuracy compared with the NY07; however, SL12 yields a 15.1% underestimation rate while NY07 overestimated the SCF with a 15.2% overestimation rate. Both two schemes capture the distribution of the maximum snow depth well but show large positive biases in the average value through all periods (3.37, 3.15, and 1.48 cm for NY07; 3.91, 3.52, and 1.17 cm for SL12) and overestimate snow cover days compared with the satellite-based product and in situ observations. Higher altitudes show larger root-mean-square errors (RMSEs) in the simulations of snow depth and snow cover days during the snow-free period. Moreover, the surface energy flux estimations from the SL12 scheme are generally superior to the simulation from NY07 when evaluated against ground-based observations, in particular for net radiation and sensible heat flux. This study has great implications for further improvement of the subgrid-scale snow variations over the Tibetan Plateau.
Landmeyer, J.E.; Chapelle, F.H.; Petkewich, M.D.; Bradley, P.M.
1998-01-01
Shallow, anaerobic groundwater near a former manufactured-gas plant (MGP) in Charleston, South Carolina, USA, contains mono- and polycyclic aromatic hydrocarbons (MAHs and PAHs, respectively). Between 1994 and 1997, a combination of field, laboratory, and numerical-flow and transport-model investigations were made to assess natural attenuation processes affecting MAH and PAH distributions. This assessment included determination of adsorption coefficients (K(ad)) and first-order biodegradation rate constants (K(bio)) using aquifer material from the MGP site and adjacent properties. Naphthalene adsorption (K(ad) = 1.35 x 10-7 m3/mg) to aquifer sediments was higher than toluene adsorption (K(ad) = 9.34 x 10-10 m3/mg), suggesting preferential toluene transport relative to naphthalene. However, toluene and benzene distributions measured in January 1994 were smaller than the naphthalene distribution. This scenario can be explained, in part, by the differences between biodegradation rates of the compounds. Aerobic first-order rate constants of 14C-toluene, 14C-benzene, and 14C-naphthalene degradation were similar (-0.84, -0.03, and 0.88 day-1, respectively), but anaerobic rate constants were higher for toluene and benzene (-0.002 and -0.00014 day-1, respectively) than for naphthalene (-0.000046 day-1). Both areal and cross-sectional numerical simulations were used to test the hypothesis suggested by these rate differences that MAH compounds will be contained relative to PAHs. Predictive simulations indicated that the distributions of toluene and benzene reach steady-state conditions before groundwater flow lines discharge to an adjacent surface-water body, but do discharge low concentrations of naphthalene. Numerical predictions were 'audited' by measuring concentrations of naphthalene, toluene, and benzene at the site in early 1997. Measured naphthalene and toluene concentrations were substantially reduced and the areal extent of contamination smaller than was both observed in January 1994 and predicted for 1997. Measured 1997 benzene concentrations and distribution were shown to be relatively unchanged from those measured in 1994, and similar to predictions for 1997.The natural attenuation processes affecting mono- and polycyclic aromatic hydrocarbons (MAHs and PAHs, respectively) distributions in groundwater near a former manufactured-gas plant in South Carolina, USA was evaluated. This assessment included determination of adsorption coefficients and first-order biodegradation rate constants. Detailed results obtained in the study are presented.
Effect of a surfactant on the antimicrobial activity of sodium hypochlorite solutions.
Bolfoni, Marcos Rodolfo; Ferla, Marcelo dos Santos; Sposito, Otávio da Silva; Giardino, Luciano; Jacinto, Rogério de Castilho; Pappen, Fernanda Geraldes
2014-01-01
The objective of the present study was to evaluate the antimicrobial activity of sodium hypochlorite (NaOCl) associated with a surfactant. Seventy single-rooted extracted human teeth were inoculated with Enterococcus faecalis, and incubated for 21 days (37 °C). The groups were distributed according to the irrigation solution used during root canal preparation: 5%, 2.5% and 1% NaOCl; 5%, 2.5% and 1% Hypoclean®, a solution containing a surfactant (cetrimide) associated with NaOCl. Three microbiological samples were collected from each tooth: S1 - before instrumentation; S2 - immediately after instrumentation; and S3 - after a seven-day period. Data were submitted to ANOVA and Tukey test with 5% significance level. The results showed that immediately after root canal preparation (S2), E. faecalis was eliminated in all the experimental groups. However, after 7 days (S3), only the groups in which Hypoclean was used, remained contamination-free, including Hypoclean associated with 1% NaOCl, while the root canals irrigated with 1% NaOCl only, presented the highest percentage of bacterial growth. In conclusion, the addition of surfactant increased the antimicrobial activity of 1% NaOCl to levels similar to 5% NaOCl.
Global Magnetic Variability at Planetary Wave Periods
NASA Astrophysics Data System (ADS)
Forbes, J. M.; Behm, J.
2017-12-01
Planetary waves (PW) and PW-tide interactions are thought to introduce multi-day periodicities ( 2-20 days) in the electric fields and currents induced by the wind dynamo mechanism in the ionospheric E-region (ca. 100-150 km), and thus can provide important insights on coupling between the lower atmosphere and the ionosphere. Previous studies have used a relatively small subset of available data to infer the existence of these variations in ground magnetic measurements. In some cases connections were made with contemporaneous measurements of neutral wind dynamics. In the present work, we employ ground-based magnetometer data from over 100 stations from the INTERMAGNET network during 2009 to gain a global perspective on eastward- and westward-propagating and zonally-symmetric oscillations with PW periods. Our presentation describes how the unevenly-spaced global data are re-gridded onto an icosahedral grid prior to analysis, and assesses how gaps in the distribution of points across the grid affect extraction of some parts of the spectrum. Consideration is also given to possible contamination by recurrent magnetic activity at subharmonics of 27 days. The global evolution of several PW components during 2009 are depicted and interpreted.
NASA Astrophysics Data System (ADS)
Martin, M. A.; Winkelmann, R.; Haseloff, M.; Albrecht, T.; Bueler, E.; Khroulev, C.; Levermann, A.
2010-08-01
We present a dynamic equilibrium simulation of the ice sheet-shelf system on Antarctica with the Potsdam Parallel Ice Sheet Model (PISM-PIK). The simulation is initialized with present-day conditions for topography and ice thickness and then run to steady state with constant present-day surface mass balance. Surface temperature and basal melt distribution are parameterized. Grounding lines and calving fronts are free to evolve, and their modeled equilibrium state is compared to observational data. A physically-motivated dynamic calving law based on horizontal spreading rates allows for realistic calving fronts for various types of shelves. Steady-state dynamics including surface velocity and ice flux are analyzed for whole Antarctica and the Ronne-Filchner and Ross ice shelf areas in particular. The results show that the different flow regimes in sheet and shelves, and the transition zone between them, are captured reasonably well, supporting the approach of superposition of SIA and SSA for the representation of fast motion of grounded ice. This approach also leads to a natural emergence of streams in this new 3-D marine ice sheet model.
Hellevang, Helge; Aagaard, Per
2015-01-01
Land-use changes until the beginning of the 20th century made the terrestrial biosphere a net source of atmospheric carbon. Later, burning of fossil fuel surpassed land use changes as the major anthropogenic source of carbon. The terrestrial biosphere is at present suggested to be a carbon sink, but the distribution of excess anthropogenic carbon to the ocean and biosphere sinks is highly uncertain. Our modeling suggest that land-use changes can be tracked quite well by the carbon isotopes until mid-20th century, whereas burning of fossil fuel dominates the present-day observed changes in the isotope signature. The modeling indicates that the global carbon isotope fractionation has not changed significantly during the last 150 years. Furthermore, increased uptake of carbon by the ocean and increasing temperatures does not yet appear to have resulted in increasing the global gross ocean-to-atmosphere carbon fluxes. This may however change in the future when the excess carbon will emerge in the ocean upwelling zones, possibly reducing the net-uptake of carbon compared to the present-day ocean. PMID:26611741
Parallel discrete event simulation: A shared memory approach
NASA Technical Reports Server (NTRS)
Reed, Daniel A.; Malony, Allen D.; Mccredie, Bradley D.
1987-01-01
With traditional event list techniques, evaluating a detailed discrete event simulation model can often require hours or even days of computation time. Parallel simulation mimics the interacting servers and queues of a real system by assigning each simulated entity to a processor. By eliminating the event list and maintaining only sufficient synchronization to insure causality, parallel simulation can potentially provide speedups that are linear in the number of processors. A set of shared memory experiments is presented using the Chandy-Misra distributed simulation algorithm to simulate networks of queues. Parameters include queueing network topology and routing probabilities, number of processors, and assignment of network nodes to processors. These experiments show that Chandy-Misra distributed simulation is a questionable alternative to sequential simulation of most queueing network models.
Present-day deformation across the Basin and Range Province, western United States
Thatcher, W.; Foulger, G.R.; Julian, B.R.; Svarc, J.; Quilty, E.; Bawden, G.W.
1999-01-01
The distribution of deformation within the Basin and Range province was determined from 1992, 1996, and 1998 surveys of a dense, 800-kilometer- aperture, Global Positioning System network, Internal deformation generally follows the pattern of Holocene fault distribution and is concentrated near the western extremity of the province, with lesser amounts focused near the eastern boundary. Little net deformation occurs across the central 500 kilometers of the network in western Utah and eastern Nevada. Concentration of deformation adjacent to the rigid Sierra Nevada block indicates that external plate-driving forces play an important role in driving deformation, modulating the extensional stress field generated by internal buoyancy forces that are due to lateral density gradients and topography near the province boundaries.
Feasibility of satellite quantum key distribution
NASA Astrophysics Data System (ADS)
Bonato, C.; Tomaello, A.; Da Deppo, V.; Naletto, G.; Villoresi, P.
2009-04-01
In this paper, we present a novel analysis of the feasibility of quantum key distribution between a LEO satellite and a ground station. First of all, we study signal propagation through a turbulent atmosphere for uplinks and downlinks, discussing the contribution of beam spreading and beam wandering. Then we introduce a model for the background noise of the channel during night-time and day-time, calculating the signal-to-noise ratio for different configurations. We also discuss the expected error-rate due to imperfect polarization compensation in the channel. Finally, we calculate the expected key generation rate of a secure key for different configurations (uplink, downlink) and for different protocols (BB84 with and without decoy states, entanglement-based Ekert91 protocol).
Stivala, Craig E; Benoit, Evelyne; Aráoz, Rómulo; Servent, Denis; Novikov, Alexei; Molgó, Jordi; Zakarian, Armen
2015-03-01
From a small group of exotic compounds isolated only two decades ago, Cyclic Imine (CI) toxins have become a major class of marine toxins with global distribution. Their distinct chemical structure, biological mechanism of action, and intricate chemistry ensures that CI toxins will continue to be the subject of fascinating fundamental studies in the broad fields of chemistry, chemical biology, and toxicology. The worldwide occurrence of potent CI toxins in marine environments, their accumulation in shellfish, and chemical stability are important considerations in assessing risk factors for human health. This review article aims to provide an account of chemistry, biology, and toxicology of CI toxins from their discovery to the present day.
The distribution of middle tropospheric carbon monoxide during early October 1984
NASA Technical Reports Server (NTRS)
Reichle, Henry G., Jr.; Connors, Vickie S.; Wallio, H. Andrew; Holland, J. Alvin; Sherrill, Robert T.; Casas, Joseph C.; Gormsen, Barbara B.
1989-01-01
The distribution of middle tropospheric carbon monoxide measure by the Measurement of Air Pollution from Satellites (MAPS) instrument carried aboard the space shuttle is reported. The data represent average mixing ratios in the middle troposphere and are presented in the form of maps that show the carbon monoxide mixing ratios averaged for 6 days of the mission. Comparisons with concurrent, direct measurements taken aboard aircraft show that the inferred concentrations are systematically low by from 20 to 40 percent depending upon which direct measurement calibration standard is used. The data show that there are very large CO sources resulting from biomass burning over South America and southern Africa. Measured mixing ratios were high over northeast Asia and were highly variable over Europe.
Time coded distribution via broadcasting stations
NASA Technical Reports Server (NTRS)
Leschiutta, S.; Pettiti, V.; Detoma, E.
1979-01-01
The distribution of standard time signals via AM and FM broadcasting stations presents the distinct advantages to offer a wide area coverage and to allow the use of inexpensive receivers, but the signals are radiated a limited number of times per day, are not usually available during the night, and no full and automatic synchronization of a remote clock is possible. As an attempt to overcome some of these problems, a time coded signal with a complete date information is diffused by the IEN via the national broadcasting networks in Italy. These signals are radiated by some 120 AM and about 3000 FM and TV transmitters around the country. In such a way, a time ordered system with an accuracy of a couple of milliseconds is easily achieved.
1998-09-01
distribution CSAS-100-HV 7 m (Surf-2) 0.16-32 .gm PMS2 CSASP-200 Base of Pier 15 m (Surf-1,3) Aerosol size distribution 11.2 m (Surf-2) 0.2-20 pm PMS3 CSASP-100...270 4 180 V ~C2 go 1P-2 PMS3.(6m..) PM.Sl.(12.) PMS2 in.)... ...... Reference -2- ....... .... ..... ............... kn - .2 25 26 27 28 Day number...1 (12 in) are presently available do not allow for a more sophisticated 3 ..... PMS2 (15 m) approach. 2 The horizontal aerosol flux downwind from the
Stuhler, John D; Orrock, John L
2016-06-01
Historical agriculture and present-day fire regimes can have significant effects on contemporary ecosystems. Although past agricultural land use can lead to long-term changes in plant communities, it remains unclear whether these persistent land-use legacies alter plant-consumer interactions, such as seed predation, and whether contemporary disturbance (e.g., fire) alters the effects of historical agriculture on these interactions. We conducted a study at 27 sites distributed across 80,300 ha in post-agricultural and non-agricultural longleaf pine woodlands with different degrees of fire frequency to test the hypothesis that past and present-day disturbances that alter plant communities can subsequently alter seed predation. We quantified seed removal by arthropods and rodents for Tephrosia virginiana and Vernonia angustifolia, species of conservation interest. We found that the effects of land-use history and fire frequency on seed removal were contingent on granivore guild and microhabitat characteristics. Tephrosia virginiana removal was greater in low fire frequency sites, due to greater seed removal by rodents. Although overall removal of V. angustifolia did not differ among habitats, rodents removed more seeds than arthropods at post-agricultural sites and non-agricultural sites with low fire frequencies, but not at non-agricultural sites with high fire frequencies. Land-use history and fire frequency also affected the relationship between microhabitat characteristics and removal of V. angustifolia. Our results suggest that historical agriculture and present-day fire regimes may alter seed predation by shifting the impact of rodent and arthropod seed predators among habitats, with potential consequences for the establishment of rare plant species consumed by one or both predators.
NASA Astrophysics Data System (ADS)
Kanada, S.; Nakano, M.; Nakamura, M.; Hayashi, S.; Kato, T.; Kurihara, K.; Sasaki, H.; Uchiyama, T.; Aranami, K.; Honda, Y.; Kitoh, A.
2008-12-01
In order to study changes in the regional climate in the vicinity of Japan during the summer rainy season due to global warming, experiments by a semi-cloud resolving non-hydrostatic model with a horizontal resolution of 5km (NHM-5km) have been conducted from June to October by nesting within the results of the 10-year time-integrated experiments using a hydrostatic atmospheric general circulation model with a horizontal grid of 20 km (AGCM-20km: TL959L60) for the present and future up to the year 2100. A non-hydrostatic model developed by the Japan Meteorological Agency (JMA) (JMA-NHM; Saito et al. 2001, 2006) was adopted. Detailed descriptions of the NHM-5km are shown by the poster of Nakano et al. Our results show that rainy days over most of the Japanese Islands will decrease in June and July and increase in August and September in the future climate. Especially, remarkable increases in intense precipitations such as larger than 150 - 300 mm/day are projected from the present to future climate. The 90th percentiles of regional largest values among maximum daily precipitations (R-MDPs) grow 156 to 207 mm/day in the present and future climates, respectively. It is well-known that the horizontal distribution of precipitation, especially the heavy rainfall in the vicinity of Japan, much depends on the topography. Therefore, higher resolution experiments by a cloud-resolving model with a horizontal resolution of 1km (NHM-1km) are one-way nested within the results of NHM-5km. The basic frame and design of the NHM-1km is the same as those of the NHM-5km, but the topography is finer and no cumulus parameterization is used in the NHM-1km experiments. The NHM-1km, which treats the convection and cloud microphysics explicitly, can represent not only horizontal distributions of rainfall in detail but also the 3-dimensional structures of meso-beta-scale convective systems (MCSs). Because of the limitation of computation resources, only heavy rainfall events that rank in top 10 % of all rainfall events are selected for the NHM-1km experiments (Heavy rainfall events are defined by R-MDPs > 156 and 207 mm/day for the present and future climates, respectively, from the results of the NHM-5km). Tentative comparisons between the results of the NHM-1km and NHM-1km experiments reveal that the NHM-1km can re-produce more detailed and realistic horizontal distributions of rainfall in many cases. (This study is supported by the Ministry of Education, Culture, Sports, Science and Technology under the framework of the KAKUSHIN program. Numerical simulations are performed in the Earth Simulator)
Detection of pathogens in food using a SERS-based assay in just a few hours
NASA Astrophysics Data System (ADS)
Shende, Chetan; Sengupta, Atanu; Huang, Hermes; Farquharson, Stuart
2014-05-01
In 2011 Escherichia, Listeria, and Salmonella species infected over 1.2 million people in the United States, resulting in over 23,000 hospitalizations and 650 deaths. In January 2013 President Obama signed into law the Food and Drug Administration (FDA) Food Safety Modernization Act (FSMA), which requires constant microbial testing of food processing equipment and food to minimize contamination and distribution of food tainted with pathogens. The challenge to preventing distribution and consumption of contaminated foods lies in the fact that just a few bacterial cells can rapidly multiply to millions, reaching infectious doses within a few days. Unfortunately, current methods used to detect these few cells rely on similar growth steps to multiply the cells to the point of detection, which also takes a few days. Consequently, there is a critical need for an analyzer that can rapidly extract and detect foodborne pathogens at 1000 colony forming units per gram of food in 1-2 hours (not days), and with a specificity that differentiates from indigenous microflora, so that false alarms are eliminated. In an effort to meet this need, we have been developing an assay that extracts such pathogens from food, selectively binds these pathogens, and produces surface-enhanced Raman spectra (SERS) when read by a Raman analyzer. Here we present SERS measurements of these pathogens in actual food samples using this assay.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Beeston, Michael Philip; University of Exeter in Cornwall; Tuen van Elteren, Johannes
A methodology is presented to study the physico-chemical processes in old tailings ponds using an array of analytical-physical chemistry approaches. A case study was conducted on the sorption/desorption behaviour of arsenic in tailings pond 2406, at the King Edward Mine (KEM) in Cornwall, UK. The tailings pond was in operation from approximately 1907 to 1921. The methodology involves two principal stages: (1) sequential extraction followed by subsequent arsenic species determination to characterise the material with regards to the association of arsenic with soil phases and identification of As (III/V) in the easily accessible soil phase; (2) batch contacting/equilibrating the tailingsmore » pond material with As(III/V), followed by a similar procedure as in stage 1 to establish the material's As(III/V) phase distribution kinetics/thermodynamics. By extrapolating the data from present day samples we infer past and future elemental mobility. From this study it is concluded that adsorption and desorption from tailings material is a rapid process for the most unstable soil phases (non-specific and specific) and a slow process for the more stable phases (poorly crystalline and well crystalline). The hypothetical application of this conclusion to the tailings from dam 2406 is that, during the initial phases of the dam's creation (ca. 100 years ago), when arsenic was both in solution and bound to mineralogical components, arsenic must have dispersed into the environment as a result of slow As(V) adsorption/phase distribution processes. Aging of the tailings material sees the movement of the arsenic to the more stable soil phases, producing a situation that is seen at present day.« less
Larangeira, Paula Martins; de Rosso, Veridiana Vera; da Silva, Victor Hugo Pereira; de Moura, Carolina Foot Gomes; Ribeiro, Daniel Araki
2016-11-01
The ionic liquid or melted salt 1-Butyl-3-methylimidazolium is an alternative process to extract natural pigments, such as carotenoids. Lycopene represents 80-90% of total of carotenoids presents in tomatoes and it has been widely studied due its potent antioxidant action. The aim of this study was to evaluate genotoxicity, mutagenicity and cytotoxicity of carotenoids extracted from ionic liquid using experimental model in vivo. For this purpose, a total of 20 male Wistar rats were distributed into four groups (n=5), as follows: control group; received a corresponding amount of corn oil for 7days by intragastric gavage (i.g.), ionic liquid group, received 10mgkg -1 body weight for 7days by gavage; 10mg carotenoids group, received 10mgkg -1 bw dissolved in corn oil for 7days by gavage and 500mg carotenoids group, received 500mgkg -1 bw dissolved in corn oil for 7days by gavage. Rat liver treated with ionic liquid exhibited moderate histopathological changes randomly distributed in the parenchyma, such as cytoplasmic eosinophilia, apoptotic bodies, inflammatory infiltrate and focal necrosis. DNA damage was found in peripheral blood and liver cells of rats treated with ionic liquid or carotenoids at 500mg. An increase of micronucleated cells and 8-OhDG immunopositive cells were also detected in rats treated with carotenoids at 500mg. In summary, our results demonstrate that recommended dose for human daily intake of carotenoids extracted by ionic liquid did not induce genotoxicity, mutagenicity and cytotoxicity in multiple organs of rats. Copyright © 2016 Elsevier GmbH. All rights reserved.
VVV Survey Microlensing Events in the Galactic Center Region
NASA Astrophysics Data System (ADS)
Navarro, María Gabriela; Minniti, Dante; Contreras Ramos, Rodrigo
2017-12-01
We search for microlensing events in the highly reddened areas surrounding the Galactic center using the near-IR observations with the VISTA Variables in the Vía Láctea Survey (VVV). We report the discovery of 182 new microlensing events, based on observations acquired between 2010 and 2015. We present the color-magnitude diagrams of the microlensing sources for the VVV tiles b332, b333, and b334, which were independently analyzed, and show good qualitative agreement among themselves. We detect an excess of microlensing events in the central tile b333 in comparison with the other two tiles, suggesting that the microlensing optical depth keeps rising all the way to the Galactic center. We derive the Einstein radius crossing time for all of the observed events. The observed event timescales range from t E = 5 to 200 days. The resulting timescale distribution shows a mean timescale of < {t}{{E}}> =30.91 days for the complete sample (N = 182 events), and < {t}{{E}}> =29.93 days if restricted only for the red clump (RC) giant sources (N = 96 RC events). There are 20 long timescale events ({t}{{E}}≥slant 100 days) that suggest the presence of massive lenses (black holes) or disk-disk event. This work demonstrates that the VVV Survey is a powerful tool to detect intermediate/long timescale microlensing events in highly reddened areas, and it enables a number of future applications, from analyzing individual events to computing the statistics for the inner Galactic mass and kinematic distributions, in aid of future ground- and space-based experiments.
Anderson, Liam; Naughton, Robert J; Close, Graeme L; Di Michele, Rocco; Morgans, Ryland; Drust, Barry; Morton, James P
2017-12-01
The daily distribution of macronutrient intake can modulate aspects of training adaptations, performance and recovery. We therefore assessed the daily distribution of macronutrient intake (as assessed using food diaries supported by the remote food photographic method and 24-hr recalls) of professional soccer players (n = 6) of the English Premier League during a 7-day period consisting of two match days and five training days. On match days, average carbohydrate (CHO) content of the prematch (<1.5 g·kg -1 body mass) and postmatch (1 g·kg -1 body mass) meals (in recovery from an evening kick-off) were similar (p > .05) though such intakes were lower than contemporary guidelines considered optimal for prematch CHO intake and postmatch recovery. On training days, we observed a skewed and hierarchical approach (p < .05 for all comparisons) to protein feeding such that dinner (0.8 g·kg -1 )>lunch (0.6 g·kg -1 )>breakfast (0.3 g·kg -1 )>evening snacks (0.1 g·kg -1 ). We conclude players may benefit from consuming greater amounts of CHO in both the prematch and postmatch meals so as to increase CHO availability and maximize rates of muscle glycogen resynthesis, respectively. Furthermore, attention should also be given to ensuring even daily distribution of protein intake so as to potentially promote components of training adaptation.
RainyDay: An Online, Open-Source Tool for Physically-based Rainfall and Flood Frequency Analysis
NASA Astrophysics Data System (ADS)
Wright, D.; Yu, G.; Holman, K. D.
2017-12-01
Flood frequency analysis in ungaged or changing watersheds typically requires rainfall intensity-duration-frequency (IDF) curves combined with hydrologic models. IDF curves only depict point-scale rainfall depth, while true rainstorms exhibit complex spatial and temporal structures. Floods result from these rainfall structures interacting with watershed features such as land cover, soils, and variable antecedent conditions as well as river channel processes. Thus, IDF curves are traditionally combined with a variety of "design storm" assumptions such as area reduction factors and idealized rainfall space-time distributions to translate rainfall depths into inputs that are suitable for flood hydrologic modeling. The impacts of such assumptions are relatively poorly understood. Meanwhile, modern precipitation estimates from gridded weather radar, grid-interpolated rain gages, satellites, and numerical weather models provide more realistic depictions of rainfall space-time structure. Usage of such datasets for rainfall and flood frequency analysis, however, are hindered by relatively short record lengths. We present RainyDay, an open-source stochastic storm transposition (SST) framework for generating large numbers of realistic rainfall "scenarios." SST "lengthens" the rainfall record by temporal resampling and geospatial transposition of observed storms to extract space-time information from regional gridded rainfall data. Relatively short (10-15 year) records of bias-corrected radar rainfall data are sufficient to estimate rainfall and flood events with much longer recurrence intervals including 100-year and 500-year events. We describe the SST methodology as implemented in RainyDay and compare rainfall IDF results from RainyDay to conventional estimates from NOAA Atlas 14. Then, we demonstrate some of the flood frequency analysis properties that are possible when RainyDay is integrated with a distributed hydrologic model, including robust estimation of flood hazards in a changing watershed. The U.S. Bureau of Reclamation is supporting the development of a web-based variant of RainyDay, a "beta" version of which is available at http://her.cee.wisc.edu/projects/rainyday/.
Le Jouan, M.; Jullien, V.; Tetanye, E.; Tran, A.; Rey, E.; Tréluyer, J.-M.; Tod, M.; Pons, G.
2005-01-01
The aim of the present study was to assess the pharmacokinetics and the efficacy of a shorter than usual 5-day quinine treatment given orally to children in Cameroon with malaria caused by Plasmodium falciparum. Quinine (8.3 mg of base per kg of body weight every 8 h) was administered as a 2% formiate salt syrup for 5 days to 30 children (age range, 0.55 to 6.7 years) with uncomplicated falciparum malaria (initial parasitemia, 1.4 × 103 to 1.8 × 105/μl). Quinine concentrations in plasma samples (five to nine per patient) were measured by liquid chromatography on days 1 to 3. Parasitemia was counted on days 0, 1, 2, 3, 4, 7, and 14. Pharmacokinetic and pharmacodynamic data were analyzed by population approaches by using NONMEM and WinBugs, respectively. The kinetics of quinine were best described by a one-compartment model with time-varying protein binding. Clearance and the volume of distribution were positively correlated with body weight and increased over time. Parasitemia was undetectable from day 3 to 14 in all children. The time to a 4-log reduction of the initial level of parasitemia (Ter) was related to the average quinine concentration from 0 to 72 h (Cav) as Ter = Tmin [1 + (C50/Cav)s], where sigmoidicity (s) is equal to 2, Tmin is the time to eradication at infinite Cav, and C50 is the value of Cav for which Ter is twice Tmin. The C50 distribution was unimodal, and all C50 values were less than 8 mg/liter, while Cav ranged from 5.9 to 18.3 mg/liter. The median (10th to 90th percentile) Ter was 47 h (range, 39 to 76 h). The efficacy of a 5-day treatment course should be evaluated in a larger clinical trial. PMID:16127036
Malisova, O; Bountziouka, V; Panagiotakos, D Β; Zampelas, A; Kapsokefalou, M
2013-07-01
Water balance is achieved when water intake from solid and fluid foods and drinking water meets water losses, mainly in sweat, urine and faeces. Seasonality, particularly in Mediterranean countries that have a hot summer, may affect water loss and consequently water balance. Water balance has not been estimated before on a population level and the effect of seasonality has not been evaluated. The present study aimed to compare water balance, intake and loss in summer and winter in a sample of the general population in Greece. The Water Balance Questionnaire (WBQ) was used to evaluate water balance, estimating water intake and loss in summer (n = 480) and in winter (n = 412) on a stratified sample of the general population in Athens, Greece. In winter, mean (SD) water balance was -63 (1478) mL/day(-1) , mean (SD)water intake was 2892 (987) mL/day(-1) and mean (quartile range) water loss was 2637 (1810-3922) mL/day(-1) . In summer, mean (SD) water balance was -58 (2150) mL/day(-1) , mean (SD) water intake was 3875 (1373) mL/day(-1) and mean (quartile range) water loss was 3635 (2365-5258) mL/day(-1) . Water balance did not differ between summer and winter (P = 0.96); however, the data distribution was different; in summer, approximately 8% more participants were falling in the low and high water balance categories. Differences in water intake from different sources were identified (P < 0.05). Water balance in summer and winter was not different. However, water intake and loss were approximately 40% higher in summer than in winter. More people were falling in the low and high water balance categories in summer when comparing the distribution on water balance in winter. © 2013 The Authors Journal of Human Nutrition and Dietetics © 2013 The British Dietetic Association Ltd.
Numerical Simulation of Ground-Water Withdrawals in the Southern Lihue Basin, Kauai, Hawaii
Izuka, Scot K.; Oki, Delwyn S.
2002-01-01
Numerical simulations indicate that ground-water withdrawals from the Hanamaulu and Puhi areas of the southern Lihue Basin will result in a decline in water levels and reductions in base flows of streams near proposed new water-supply wells. Most of the changes will be attained within 10 to 20 years of the start of pumping. Except for areas such as Puhi and Kilohana, the freshwater lens in most inland areas of the southern Lihue Basin is thick and model simulations indicate that changes in water level and the position of the freshwater- saltwater interface in response to pumping will be small relative to the present thickness of the freshwater lens. Effects of the proposed withdrawals on streamflow depend on withdrawal rate and proximity of the wells to streams. Placing pumped wells away from streams with low base flow and toward streams with high base flow can reduce the relative effect on individual streams. Simulation of the 0.42-million-gallon-per-day increase in withdrawal projected for 2000 indicates that the resulting changes in water levels and interface position, relative to conditions prior to the withdrawal increase, will be small, and that stream base flow will be reduced by less than 10 percent. Simulation of the 0.83-million-gallon-per-day withdrawal projected for 2010 indicates further thinning of the freshwater lens in the Puhi area, where the lens already may be thin, as well as base-flow reduction in Nawiliwili Stream. Simulation of an alternative distribution of the 0.83-million-gallon-per-day withdrawal indicates that the effects can be reduced by shifting most of the new withdrawal to the Hanamaulu area where the freshwater lens is thicker and stream base flows are greater. Simulation of the 1.16-million-gallon-per-day increase in withdrawal projected for 2020 indicates that if withdrawal is distributed only among Hana-maulu wells 1, 3, and 4, and Puhi well 5A, further thinning of the already-thin freshwater lens in the Puhi area would occur. Such a distribution would also exceed the maximum draft recommended by the water-systems standards used in Hawaii. Another simulation in which part of the 1.16 million gallons per day was distributed among three additional hypothetical wells in the Hanamaulu area showed that the pumping effects could be shifted from the Puhi area to the Hanamaulu area, where the freshwater lens is thicker, but that base flow in Hanamaulu Stream may decrease by as much as 16 percent.
Postnatal development of retinal projections in the brushtailed possum, Trichosurus vulpecula.
Sanderson, K J; Dixon, P G; Pearson, L J
1982-10-01
The postnatal development of retinal projections was studied in the brushtailed possum, Trichosurus vulpecula. [3H]proline was injected into one eye of 13 young possums aged 24-84 days in order to trace retinal pathways. The dorsal lateral geniculate nucleus (LGNd) can be identified in Nissl material at 19 days but not at 9-10 days. By 40 days some cytoarchitectural lamination of the LGNd is apparent and by 71 days the adult pattern of cell layers is present. At 24 days retinal fibers occupy by lateral part of the LGNd on both sides of the brain. By 38-40 days the retinal fibers fill be contralateral LGNd and the binocular part of the ipsilateral LGNd and there is a beginning of the segregation of retinal fibers into left and right eye territories. By 49-50 days a partial segregation is achieved, and complete segregation by 71 days. At 9-10 days the superior colliculus is not differentiated into layers and there is a thick zone of cell proliferation around the ventricle. By 23 days the superior colliculus has well-defined cell layers and there is still some indication of cell proliferation around the ventricle. By 40 days, the superior colliculus shows little evidence of cell proliferation. At 24 days retinal fibers fill the superficial layers of the contralateral optic tectum and are lightly distributed through the superficial layers of the rostral half of the ipsilateral tectum. By 38 days the ipsilateral retinal input is restricted to the deeper layers of the tectum. These results show that the adult pattern of retinal projections to the LGNd and optic tectum develops a number of weeks before eye opening occurs (at 90-120 days).
User-relevant, threshold-specific observations of climate change
NASA Astrophysics Data System (ADS)
Stainforth, Dave; Chapman, Sandra; Watkins, Nicholas
2014-05-01
Users of climate information look for details of changing climate at local scales (to inform specific activities) and on the geographical patterns of such changes (to prioritise adaptation investments). They often have user-specific thresholds of vulnerability so the changes of interest must refer to such thresholds or to the related quantile of the climatic distribution. A method for providing such information from timeseries of temperature data has recently been published [1] along with maps of changes at thresholds and quantiles [2] derived from the European Observational dataset E-Obs [3]. In this presentation we will do two things. First we will discuss the opportunities to tailor such methods to provide user-specific information through climate services, using illustrations from the existing methodology applied to daily maximum and minimum temperatures [1,2]. Second we will present new results on threshold specific observed changes in precipitation. The methodology for precipitation is related to that which has been applied to temperature but has been developed to handle the characteristics of precipitation distributions. The results identify some regions with systematic increases in precipitation on the seasonally wettest days and others which show drying across all days, on a seasonal basis. We will present the geographic locations and precipitation thresholds where strong signals of changes are seen across Europe. The coherency of such results and the methodology used to process the observational data will be discussed. We will also highlight the justifications for having confidence in the results in some regions and at some thresholds while having a lack of confidence in others. Such information should be an important element of any climate services. It is worth noting that here "wettest days" refers to events which are uncommon within a season (e.g. one in ~20 wet days). This is in contrast and complementary to, for instance, the one in a hundred year extreme event. Users can be vulnerable to one or the other or both of these event types and climate services are required which are sufficiently flexible to provide tailored information in either situation. It is common to focus on the latter while the former is relatively understudied. [1] Chapman, S C, Stainforth, D A, Watkins, N W. 2013 On Estimating Local Long Term Climate Trends, Phil. Trans. R. Soc. A, 371 20120287; [2] Stainforth, D A, Chapman, S. C. & Watkins, N. W. 2013. Mapping climate change in European temperature distributions Environ. Res. Lett. 8 034031 [3] Haylock, M.R., N. Hofstra, A.M.G. Klein Tank, E.J. Klok, P.D. Jones and M. New. 2008: A European daily high-resolution gridded dataset of surface temperature and precipitation. J. Geophys. Res (Atmospheres), 113, D20119
The Numerical Electromagnetics Code (NEC) - A Brief History
DOE Office of Scientific and Technical Information (OSTI.GOV)
Burke, G J; Miller, E K; Poggio, A J
The Numerical Electromagnetics Code, NEC as it is commonly known, continues to be one of the more widely used antenna modeling codes in existence. With several versions in use that reflect different levels of capability and availability, there are now 450 copies of NEC4 and 250 copies of NEC3 that have been distributed by Lawrence Livermore National Laboratory to a limited class of qualified recipients, and several hundred copies of NEC2 that had a recorded distribution by LLNL. These numbers do not account for numerous copies (perhaps 1000s) that were acquired through other means capitalizing on the open source code,more » the absence of distribution controls prior to NEC3 and the availability of versions on the Internet. In this paper we briefly review the history of the code that is concisely displayed in Figure 1. We will show how it capitalized on the research of prominent contributors in the early days of computational electromagnetics, how a combination of events led to the tri-service-supported code development program that ultimately led to NEC and how it evolved to the present day product. The authors apologize that space limitations do not allow us to provide a list of references or to acknowledge the numerous contributors to the code both of which can be found in the code documents.« less
Lee, Jong Joo; Jang, Jeong Hun; Choo, Oak-Sung; Lim, Hye Jin; Choung, Yun-Hoon
2018-01-01
Steroids have been widely used to treat inner-ear diseases such as sudden sensorineural hearing loss, tinnitus, and Meniere's disease. They can be given via either systemic or intratympanic (IT) injection. The purpose of the present study was to explore differences in intracochlear steroid distribution by the administration method employed (systemic vs. IT injection). Animal study. Twenty-three Sprague-Dawley rats were given fluorescein isothiocyanate-labeled dexamethasone (FITC-DEX) three times (on successive days) via intraperitoneal (IP) or IT injection. Cochlear uptake of FITC-DEX was evaluated via immunohistochemistry and flow cytometry at 6 hours, and 3 and 7 days after the final injection. FITC-DEX uptake was evident in spiral ganglion cells (SGs), the organ of Corti (OC), and the lateral walls (LWs), the basal turns of which were stained relatively prominently in both groups. Animals receiving IP injections exhibited higher FITC-DEX uptakes by the SGs and OC, whereas IT injection triggered higher-level FITC-DEX accumulation by the OC and LWs. Flow cytometry revealed that intracochlear FITC-DEX uptake by IT-injected animals was higher and more prolonged than in animals subjected to IP injections. We thus describe differences in cochlear steroid distributions after systemic and IT injections. This finding could help our understanding of the pharmacokinetics of steroids in the cochlea. NA. Laryngoscope, 128:189-194, 2018. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.
Aamir, Muhammad; Khan, Sardar; Nawab, Javed; Qamar, Zahir; Khan, Anwarzeb
2016-03-01
Distribution of hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethane (DDT) congeners in tissues of four different fish species and their associated potential health risks to local consumers are presented in this paper. The average ∑(HCHs+DDTs) concentration in Glyptothorax punjabensis (214ngg(-1) wet weight (ww)) (carnivores) was found higher than Tor putitora (155ngg(-1) ww) (herbivores). The distribution of ∑(HCHs+DDTs) in all fish tissues was found in order of liver>muscle>stomach>gills. The profile of congeners (β-HCH/∑HCH from 0.29-0.47) indicated that all selected fish species were contaminated with HCH because of its recent usage in the study area. Furthermore, DDT profile ((DDE+DDD)/∑DDT from 0.61-0.78) showed that fish contamination with DDT originated from past usage and long-time degradation mechanism. The average estimated daily dietary intake of ∑HCHs (15.0ngkg(-1) day(-1)) was higher than ∑DDTs (12.5ngkg(-1) day(-1)) by the local consumers via fish consumption. On the basis of both 50th and 95th percentile exposure levels, the carcinogenic hazard ratios for DDT and its congeners were exceeded one (safe limit) for all fish species, indicating a great potential cancer risk for local consumers with life time consumption of contaminated fish collected from Kabul River. Copyright © 2015 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Mendoza, W. G.; Zika, R. G.
2009-12-01
Colored dissolved organic matter (CDOM) plays an important key role in the photochemistry and biogeochemical cycling of carbon in the coastal region. Their distribution can vary in space and time due to supply of CDOM from different sources. To determine properties of fluorescence-CDOM produced by various marine tropical species, two species from each of the different marine communities were examined after incubation in the dark for forty-nine (49) days: seagrasses-Enhalus acoroides (EA), Thalassia testudinium (TT); corals-Pocillopora cylindrical (PC), Seriatopora hystrix (SH) ; mangroves- Avicennia marina (AM), Sonneratia alba (SA); brown algae-Hormophysa cuneiformis (HC), Sargassum sp.(SS). Average CDOM production is highest from mangrove species (218 QSU/g-sample/day), followed by seagrass (42 QSU/g-sample/day), brown alga (26 QSU/g-sample/day) then corals (19 QSU/g-sample/day).The fluorescence maximum at 312; 380-420 nm emission-excitation pair appears to be present in all species that is an identified humic-like signature. These results suggest that the production of the fluorescent CDOM fraction is a common phenomenon of tropical marine species and as such constitutes a major part of the marine CDOM pool in coastal regions.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Baek, Giseon; Pak, Soojong; Lee, Jeong-Eun
We carried out photometric observations for HBC 722 in the Sloan Digital Sky Survey r, i, and z bands from 2011 April to 2013 May with the Camera for QUasars in EArly uNiverse attached to the 2.1 m Otto Struve telescope at McDonald Observatory. The post-outburst phenomena were classified into five phases according to not only brightness but also color variations, which might be caused by physical changes in the emitting regions of optical and near-infrared bands. A series of spectral energy distributions (SEDs) is presented to support color variations and track the time evolution of the SED in optical/near-infraredmore » bands after the outburst. Given two years of data, possible periodicities of r, i, and z bands were checked. We found three families of signals around ∼6, ∼10, and ∼1 days in three bands, which is broadly consistent with Green et al. We also examined short-term variability (intra-day and day scales) to search for evidences of flickering by using the micro-variability method. We found clear signs of day scale variability and weak indications of intra-day scale fluctuations, which implies that the flickering event occurs in HBC 722 after outburst.« less
Prediction future asset price which is non-concordant with the historical distribution
NASA Astrophysics Data System (ADS)
Seong, Ng Yew; Hin, Pooi Ah
2015-12-01
This paper attempts to predict the major characteristics of the future asset price which is non-concordant with the distribution estimated from the price today and the prices on a large number of previous days. The three major characteristics of the i-th non-concordant asset price are the length of the interval between the occurrence time of the previous non-concordant asset price and that of the present non-concordant asset price, the indicator which denotes that the non-concordant price is extremely small or large by its values -1 and 1 respectively, and the degree of non-concordance given by the negative logarithm of the probability of the left tail or right tail of which one of the end points is given by the observed future price. The vector of three major characteristics of the next non-concordant price is modelled to be dependent on the vectors corresponding to the present and l - 1 previous non-concordant prices via a 3-dimensional conditional distribution which is derived from a 3(l + 1)-dimensional power-normal mixture distribution. The marginal distribution for each of the three major characteristics can then be derived from the conditional distribution. The mean of the j-th marginal distribution is an estimate of the value of the j-th characteristics of the next non-concordant price. Meanwhile, the 100(α/2) % and 100(1 - α/2) % points of the j-th marginal distribution can be used to form a prediction interval for the j-th characteristic of the next non-concordant price. The performance measures of the above estimates and prediction intervals indicate that the fitted conditional distribution is satisfactory. Thus the incorporation of the distribution of the characteristics of the next non-concordant price in the model for asset price has a good potential of yielding a more realistic model.
39 CFR 121.4 - Package Services.
Code of Federal Regulations, 2011 CFR
2011-07-01
... Center Facility (SCF) turnaround Package Services mail accepted at the origin SCF before the day zero... origin before the day-zero Critical Entry Time is 3 days, for each remaining (non-intra-SCF) 3-digit ZIP... intra-Network Distribution Center (NDC) Package Services mail accepted at origin before the day-zero...
39 CFR 121.4 - Package Services.
Code of Federal Regulations, 2010 CFR
2010-07-01
... Center Facility (SCF) turnaround Package Services mail accepted at the origin SCF before the day zero... origin before the day-zero Critical Entry Time is 3 days, for each remaining (non-intra-SCF) 3-digit ZIP... intra-Network Distribution Center (NDC) Package Services mail accepted at origin before the day-zero...
He, Zhuqing; Wang, Xiaoyin; Liu, Yuqing; Li, Kai
2017-10-24
Crickets of the genus Teleogryllus belong to Gryllidae, Orthoptera. Teleogryllus emma (Ohmachi and Matsumura) and T. occipitalis (Serville) are widely distributed in east Asia, but their distribution and life history have not been reported from China. We studied the seasonal and geographical adaptation by rearing these crickets and measuring specimens. The main results are as follows: T. emma belongs to short-day type, which means nymphs grow rapidly in short day conditions (LD 12:12); T. occipitalis belongs to long-day type, which means nymphs grow rapidly in long day conditions (LD 16:8). The nymphal growth rate accelerates with the increase of temperature by comparing their nymph developmental period at 25 and 30OC. T. emma is mainly distributed in the north of the Yangtze River, while T. occipitalis in the south of it. The body size decreases with the increase of latitude in both species, while the relative length of their ovipositor increases.
The Effect of Differences in Day and Night Lighting Distributions on Drivers' Speed Perception.
Kim, Jonathan D; Perrone, John A; Isler, Robert B
2017-06-01
Previous research has shown that changes to contrast levels in the visual environment caused by fog can affect drivers' perceptions of speed. It is not easy, however, to extrapolate these results to other driving scenarios in which contrast is affected, such as during nighttime driving, because the measure of contrast is more complex when considering factors such as the illumination provided by headlights. Therefore, we investigated the differences in lighting distribution patterns between day- and nighttime driving on speed perception using prerendered 3D scenarios representing driving on a rural road. A two-alternative forced-choice design based on the method of constant stimuli was utilised, with 32 participants viewing a series of pairs of scenarios (day vs. night driving) from a driver's perspective while indicating for each pair whether the second scenario was faster or slower than the first scenario. Our results indicated that speed discrimination accuracy was minimally affected by changes in lighting distribution patterns between day and night.
Abusallout, Ibrahim; Rahman, Shamimur; Hua, Guanghui
2017-11-01
Disinfection byproduct (DBP) concentrations in drinking water distribution systems and indoor water uses depend on competitive formation and degradation reactions. This study investigated the dehalogenation kinetics of total organic chlorine (TOCl), bromine (TOBr) and iodine (TOI) produced by fulvic acid under different pH and temperature conditions, and total organic halogen (TOX) variations in a treated drinking water under simulated distribution system and heating scenarios. TOX dehalogenation rates were generally in the order of TOI ≅ TOCl(NH 2 Cl) > TOBr > TOCl(Cl 2 ). The half-lives of different groups of TOX compounds formed by fulvic acid varied between 27 and 139 days during incubation at 20 °C and 0.98-2.17 days during heating at 55 °C. Base-catalyzed reactions played a major role in TOX degradation as evidenced by enhanced dehalogenation under high pH conditions. The results of heating of a treated water in the presence of residuals showed that TOX concentrations of chlorinated samples increased rapidly when chlorine residuals were present and then gradually decreased after chlorine residuals were exhausted. The final TOX concentrations of chlorinated samples after heating showed moderate decreases with increasing ambient water ages. Chloraminated samples with different ambient water ages exhibited similar final TOX concentrations during simulated distribution system and heating experiments. This study reinforces the importance of understanding DBP variations in indoor water uses as wells as in distribution systems to provide more accurate DBP information for exposure assessment and regulatory determination. Published by Elsevier Ltd.
Opell, Brent D.; Haddad, Charles R.; Raven, Robert J.; Soto, Eduardo M.; Ramírez, Martín J.
2016-01-01
Closely related organisms with transoceanic distributions have long been the focus of historical biogeography, prompting the question of whether long-distance dispersal, or tectonic-driven vicariance shaped their current distribution. Regarding the Southern Hemisphere continents, this question deals with the break-up of the Gondwanan landmass, which has also affected global wind and oceanic current patterns since the Miocene. With the advent of phylogenetic node age estimation and parametric bioinformatic advances, researchers have been able to disentangle historical evolutionary processes of taxa with greater accuracy. In this study, we used the coastal spider genus Amaurobioides to investigate the historical biogeographical and evolutionary processes that shaped the modern-day distribution of species of this exceptional genus of spiders. As the only genus of the subfamily Amaurobioidinae found on three Southern Hemisphere continents, its distribution is well-suited to study in the context of Gondwanic vicariance versus long-distance, transoceanic dispersal. Ancestral species of the genus Amaurobioides appear to have undergone several long-distance dispersal events followed by successful establishments and speciation, starting from the mid-Miocene through to the Pleistocene. The most recent common ancestor of all present-day Amaurobioides species is estimated to have originated in Africa after arriving from South America during the Miocene. From Africa the subsequent dispersals are likely to have taken place predominantly in an eastward direction. The long-distance dispersal events by Amaurobioides mostly involved transoceanic crossings, which we propose occurred by rafting, aided by the Antarctic Circumpolar Current and the West Wind Drift. PMID:27732621
Kavanaugh, David H.; Hieke, Fritz; Liang, Hongbin; Dong, Dazhi
2014-01-01
Abstract A ten-year multidisciplinary, multi-national and multi-institutional biodiversity inventory project in the Gaoligong Shan region of western Yunnan Province, China generated more than 35,000 specimens of the beetle (Coleoptera) family Carabidae. In this report, first of a planned series, we focus on diversity in tribe Zabrini. Our study of just over 1300 specimens of zabrine carabids from the project, all in genus Amara Bonelli, found a total of 13 species, all previously described, to occur in the study area, with none of them strictly endemic. We present a key for identification of adults of these species, as well as nomenclatural data, diagnoses, illustrations of dorsal habitus and male genitalia, and information about geographical, altitudinal and habitat distributions within the study area and overall geographical distribution for each species. Distributions of the species within the study area are compared, and broader geographical range patterns are characterized. We also discuss a possible role of the Gaoligong Shan region as one source area for the present-day fauna of the Himalaya and southern edge of the Qinghai-Xizang (Tibetan) Plateau. PMID:24899831
Widespread skin rash following travel to South-East Asia.
Creamer, Andrew
2014-02-20
A 21-year-old man presented with a widespread, intensely pruritic skin rash, which developed acutely 5 days after returning from a backpacking holiday in Thailand. On initial presentation to his general practitioner, an erythematous, papular rash was noted in the upper right back, with smaller clusters of lesions on the buttocks and right arm. Based on the anatomical distribution of the lesions, a preliminary diagnosis of shingles was made. Over the following 2 weeks, the lesions failed to improve, and new snake-like lesions appeared. A dermatologist made the diagnosis of cutaneous larva migrans. The skin lesions rapidly resolved following oral albendazole therapy.
Experimental evidence against transmission of Hepatozoon canis by Ixodes ricinus.
Giannelli, Alessio; Ramos, Rafael Antonio Nascimento; Dantas-Torres, Filipe; Mencke, Norbert; Baneth, Gad; Otranto, Domenico
2013-09-01
Hepatozoon canis is among the most widespread tick-borne protozoa infecting domestic and wild carnivores. Its distribution is related to the occurrence of its major vector, the brown dog tick Rhipicephalus sanguineus. However, the role of Ixodes ricinus as a vector of H. canis has been hypothesized. In the present study, the development of H. canis was investigated in I. ricinus and R. sanguineus nymphs collected from a naturally infested dog. All I. ricinus ticks examined (n=133) were negative by cytological examination at days 20, 30, and 90 post collection, although H. canis DNA was detected in one nymph at day 20 and in 2 nymphs at day 30 post collection. On the other hand, H. canis sporogony was documented by cytology, and H. canis DNA was detected by PCR in R. sanguineus at day 30 post collection. These results indicate that H. canis sporogony does not occur in I. ricinus, but in R. sanguineus, suggesting that I. ricinus does not act as a vector of H. canis. Copyright © 2013 Elsevier GmbH. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ratcliffe, D.R.
This study on passive immunity dealt principally with the following topics: pathogenesis of the pneumonia produced by influenza virus (PR8) in CF-1 mice; the distribution and retention of monoclonal antibody instilled intratracheally (IT) into the lung; and prophylaxis and therapy of influenza pneumonia using specific monoclonal antibody (IgG 2a/k anti-HA). The fate of a single 50 ul bolus of antibody instilled IT was determined by monitoring the activity of /sup 125/I-labelled monoclonal IgG in the lungs and by lavage recovery of functional antibody.Antibody was demonstrated in high concentrations for the first 3 days and was present in the lungs formore » a period of 7 days. For prophylaxis several trials indicated that monoclonal antibody provided significant protection from lethal effects of the virus. Antibody given to clinically ill mice on day 3 produced a highly significant reduction in mortality (P < 0.001) when compared to control mice. The treatment reversed the weight loss and apparently arrested the development of lesions in most of the mice within 2 days following antibody administration.« less
Hypoglycemia-Associated EEG Changes Following Antecedent Hypoglycemia in Type 1 Diabetes Mellitus.
Sejling, Anne-Sophie; Kjaer, Troels W; Pedersen-Bjergaard, Ulrik; Remvig, Line S; Frandsen, Christian S; Hilsted, Linda; Faber, Jens; Holst, Jens Juul; Tarnow, Lise; Møller, Jakob Skadkær; Nielsen, Martin N; Thorsteinsson, Birger; Juhl, Claus B
2017-02-01
Recurrent hypoglycemia has been shown to blunt hypoglycemia symptom scores and counterregulatory hormonal responses during subsequent hypoglycemia. We therefore studied whether hypoglycemia-associated electroencephalogram (EEG) changes are affected by an antecedent episode of hypoglycemia. Twenty-four patients with type 1 diabetes mellitus (10 with normal hypoglycemia awareness, 14 with hypoglycemia unawareness) were studied on 2 consecutive days by hyperinsulinemic glucose clamp at hypoglycemia (2.0-2.5 mmol/L) during a 1-h period. EEG was recorded, cognitive function assessed, and hypoglycemia symptom scores and counterregulatory hormonal responses were obtained. Twenty-one patients completed the study. Hypoglycemia-associated EEG changes were identified on both days with no differences in power or frequency distribution in the theta, alpha, or the combined theta-alpha band during hypoglycemia on the 2 days. Similar degree of cognitive dysfunction was also present during hypoglycemia on both days. When comparing the aware and unaware group, there were no differences in the hypoglycemia-associated EEG changes. There were very subtle differences in cognitive function between the two groups on day 2. The symptom response was higher in the aware group on both days, while only subtle differences were seen in the counterregulatory hormonal response. Antecedent hypoglycemia does not affect hypoglycemia-associated EEG changes in patients with type 1 diabetes mellitus.
Effects of meteorological factors and the lunar cycle on onset of parturition in cows.
Ammann, T; Hässig, M; Rüegg, S; Bleul, U
2016-04-01
The present paper summarizes a comprehensive retrospective study that was undertaken to investigate effects of meteorological factors and lunar cycle on gestation length and daily birth rate in cows. To this end, all cattle births in Switzerland between 2008 and 2010 (n=2,091,159) were related to detailed matched weather recordings. The study revealed some statistically significant effects of climate (temperature, barometric pressure, relative humidity) and weather (thunderstorms, heat index) on gestational length. Thunderstorms on the day before birth reduced the gestation length by 0.5 days. An increase in the birth rate was correlated with the temperature on the day before birth and the barometric pressure 3 days before birth. Differences in the barometric pressure >15hPa increased the birth rate by 4%. Nevertheless, the effects were not consistent and the modeled size of effect was so small that a clinical implication is unlikely. Although the daily birth rate was unevenly distributed across the lunar cycle, no clear pattern could be identified. Compared to the mean birth rate across the lunar cycle the highest daily birth rate was detected on day 4 after new moon (+1.9%) and the lowest on day 20 (-2.1%). Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.
Spatiotemporal patterns of population distribution as crucial element for risk management
NASA Astrophysics Data System (ADS)
Gokesch, Karin; Promper, Catrin; van Westen, Cees J.; Glade, Thomas
2014-05-01
The spatiotemporal distribution and presence of the population in a certain area is a crucial element within natural hazard risk management, especially in the case of rapid onset hazard events and emergency management. When fast onset hazards such as earthquakes, flash floods or industrial accidents occur, people may not have adequate time for evacuation and the emergency management requires a fast response and reaction. Therefore, information on detailed distribution of people affected by a certain hazard is important for a fast assessment of the situation including the number and the type of people (distinguishing between elderly or handicapped people, children, working population etc.) affected. This study thus aims at analyzing population distribution on an hourly basis for different days e.g. workday or holiday. The applied method combines the basic assessment of population distribution in a given area with specific location-related patterns of distribution-changes over time. The calculations are based on detailed information regarding the expected presence of certain groups of people, e.g. school children, working or elderly people, which all show different patterns of movement over certain time periods. The study area is the city of Waidhofen /Ybbs located in the Alpine foreland in the Southwest of Lower Austria. This city serves as a regional center providing basic infrastructure, shops and schools for the surrounding countryside. Therefore a lot of small and medium businesses are located in this area showing a rather high variation of population present at different times of the day. The available building footprint information was classified with respect to building type and occupancy type, which was used to estimate the expected residents within the buildings, based on the floorspace of the buildings and the average floorspace per person. Additional information on the distribution and the average duration of stay of the people in these buildings was assessed using general population statistics and specific information about selected buildings, such as schools, hospitals or homes for the elderly, to calculate the distribution patterns for each group of people over time.
Periodic variation in the geomagnetic activity - A study based on the Ap index
NASA Technical Reports Server (NTRS)
De Gonzalez, Alicia L. C.; Gonzalez, Walter D.; Dutra, Severino L. G.; Tsurutani, Bruce T.
1993-01-01
The monthly and daily samples of the Ap index for the interval from 1932 through 1982 were studied using the power spectrum technique. Results obtained for Bartel's period (about 27 days), the semiannual period, the dual-peak solar cycle distribution of geomagnetic storms, and certain other medium-scale periodicities are examined in detail. In addition, results on the cumulative occurrence number of storms per decade as a function of the Ap and Dst indices for the storm are presented.
Luna 24 regolith breccias: A possible source of the fine size material of the Luna 24 regolith
NASA Technical Reports Server (NTRS)
Rode, O. D.; Lindstrom, M. M.
1994-01-01
The regolith breccias from the Luna 24 core were analyzed. The Luna 24 regolith is a mixture of fine and coarse grain materials. The comparable analysis of the grain size distributions, the modal and chemical compositions of the breccias, and the regolith from the same levels show that the friable slightly litificated breccia with a friable fine grain matrix may be a source of fine grain material of the Luna 24 present day regolith.
JPRS Report, East Asia, Korea: Kulloja, No. 12, December 1985.
1987-06-23
the present regime," and launched an organized struggle. In particular, unlike in bygone days, the struggle of the workers of large key industrial ...2751Ü0 JPRS-AKU-87-001 23 JUNE 1987 ffflBBBl ■■■■>fl FOREIGN BROADCAST INFORMATION SERVICE JP/?S Repor WSfiffBimON STATEEv!EOT_A Approved...for p-jMic telease; Distribution Unlimited East Asia i Korea: KULLOJA No 12, DECEMBER 1985 REPRODUCED BY U.S. DEPARTMENTOF COMMERCE NATIONAL
Quantum Signature of Analog Hawking Radiation in Momentum Space.
Boiron, D; Fabbri, A; Larré, P-É; Pavloff, N; Westbrook, C I; Ziń, P
2015-07-10
We consider a sonic analog of a black hole realized in the one-dimensional flow of a Bose-Einstein condensate. Our theoretical analysis demonstrates that one- and two-body momentum distributions accessible by present-day experimental techniques provide clear direct evidence (i) of the occurrence of a sonic horizon, (ii) of the associated acoustic Hawking radiation, and (iii) of the quantum nature of the Hawking process. The signature of the quantum behavior persists even at temperatures larger than the chemical potential.
Security Police Officer Utilization Field, AFSCs 8111, 8116, 8121, and 8124.
1981-06-01
STATEMENT A M C Approved for public release 82 0 4 26Distribution Unlimited C=DCC=D= APS 8 1 X CECI I CODING INSTRUCTIONS -- -- -" Print the booklet copy...m == NAME (Last, First, Middle Initial) DATE OF BIRTH SEX YR NO DAY (MALE -"(11-34) (3s-5- rayo (41) PRESENT GRADE: SOCIAL SECURITY ACCOUNT NUMBER...Branch - 11. OIC Missile Support Branch - __m 12. OIC Weapons Systems Security , 4 8 CODE 99 X ~.t ! AFS 81XX -mmm -C - . .’ .9 - =, BACKGROUND
Disseminated cutaneous sporotrichosis.
Chang, Shurong; Hersh, Andrew M; Naughton, Greg; Mullins, Kevin; Fung, Maxwell A; Sharon, Victoria R
2013-11-15
The dimorphic fungus Sporothrix schenckii commonly causes localized cutaneous disease with lymphocutaneous distribution. However, disseminated sporotrichosis occurs predominantly in immunocompromised patients. We report a case of disseminated cutaneous sporotrichosis in a patient with newly diagnosed HIV with a CD4 count of 208. The patient presented with multiple cutaneous and subcutaneous nodules as well as fever and malaise. Tissue culture and skin biopsy confirmed the diagnosis of sporotrichosis. He was started on itraconazole 200mg twice a day with rapid resolution of fever along with cessation of the development of new lesions.
Present-Day Mars' Seismicity Predicted From 3-D Thermal Evolution Models of Interior Dynamics
NASA Astrophysics Data System (ADS)
Plesa, A.-C.; Knapmeyer, M.; Golombek, M. P.; Breuer, D.; Grott, M.; Kawamura, T.; Lognonné, P.; Tosi, N.; Weber, R. C.
2018-03-01
The Interior Exploration using Seismic Investigations, Geodesy and Heat Transport mission, to be launched in 2018, will perform a comprehensive geophysical investigation of Mars in situ. The Seismic Experiment for Interior Structure package aims to detect global and regional seismic events and in turn offer constraints on core size, crustal thickness, and core, mantle, and crustal composition. In this study, we estimate the present-day amount and distribution of seismicity using 3-D numerical thermal evolution models of Mars, taking into account contributions from convective stresses as well as from stresses associated with cooling and planetary contraction. Defining the seismogenic lithosphere by an isotherm and assuming two end-member cases of 573 K and the 1073 K, we determine the seismogenic lithosphere thickness. Assuming a seismic efficiency between 0.025 and 1, this thickness is used to estimate the total annual seismic moment budget, and our models show values between 5.7 × 1016 and 3.9 × 1019 Nm.
Atmospheric turbulence effects measured along horizontal-path optical retro-reflector links.
Mahon, Rita; Moore, Christopher I; Ferraro, Mike; Rabinovich, William S; Suite, Michele R
2012-09-01
The scintillation measured over close-to-ground retro-reflector links can be substantially enhanced due to the correlations experienced by both the direct and reflected echo beams. Experiments were carried out at China Lake, California, over a variety of ranges. The emphasis in this paper is on presenting the data from the 1.1 km retro-reflecting link that was operated for four consecutive days. The dependence of the measured irradiance flux variance on the solar fluence and on the temperature gradient above the ground is presented. The data are consistent with scintillation minima near sunrise and sunset, rising rapidly during the day and saturating at irradiance flux variances of ~10. Measured irradiance probability distributions of the retro-reflected beam are compared with standard probability density functions. The ratio of the irradiance flux variances on the retro-reflected to the direct, single-pass case is investigated with two data sets, one from a monostatic system and the other using an off-axis receiver system.
Recovery of a geocentric reference frame using the present-day GPS system
NASA Technical Reports Server (NTRS)
Malla, Rajendra P.; Wu, Sien-Chong
1990-01-01
A geocentric reference frame adopts the center of mass of the earth as the origin of the coordinate axes. The center of mass of the earth is the natural and unambiguous origin of a geocentric satellite dynamical system. But in practice a kinematically obtained terrestrial reference frame may assume an origin other than the geocenter. The establishment of a geocentric reference frame, to which all relevant observations and results can be referred and in which geodynamic theories or models for the dynamic behavior of earth can be formulated, requires the ability to accurately recover a given coordinate frame origin offset from the geocenter. GPS measurements, because of their abundance and broad distribution, provide a powerful tool to obtain this origin offset in a short period of time. Two effective strategies have been devised. Data from the First Central And South America (Casa Uno) geodynamics experiment has been studied, in order to demonstrate the ability of recovering the geocenter location with present day GPS satellites and receivers.
Ellis, Christopher J.; Yahr, Rebecca; Coppins, Brian J.
2011-01-01
This paper describes a novel archaeological resource—preserved epiphytes on the timber structure of vernacular buildings—used, to our knowledge, for the first time to quantify a loss of biodiversity between pre-industrial and post-industrial landscapes. By matching the confirmed occurrence of epiphyte species for the pre-industrial period, with a statistical likelihood for their absence in the present-day landscape (post-1960), we robustly identified species that have been extirpated across three contrasting regions in southern England. First, the scale of biodiversity loss observed—up to 80 per cent of epiphytes—severely challenges biodiversity targets and environmental baselines that have been developed using reference points in the post-industrial period. Second, we examined sensitivity in the present-day distribution of extirpated species, explained by three environmental drivers: (i) pollution regime, (ii) extent of ancient woodland, and (iii) climatic setting. Results point to an interacting effect between the pollution regime (sulphur dioxide) and changed woodland structure, leading to distinctive regional signatures in biodiversity loss. PMID:21471114
NASA Astrophysics Data System (ADS)
Jeřábková, T.; Kroupa, P.; Dabringhausen, J.; Hilker, M.; Bekki, K.
2017-12-01
The stellar initial mass function (IMF) has been described as being invariant, bottom-heavy, or top-heavy in extremely dense star-burst conditions. To provide usable observable diagnostics, we calculate redshift dependent spectral energy distributions of stellar populations in extreme star-burst clusters, which are likely to have been the precursors of present day massive globular clusters (GCs) and of ultra compact dwarf galaxies (UCDs). The retention fraction of stellar remnants is taken into account to assess the mass to light ratios of the ageing star-burst. Their redshift dependent photometric properties are calculated as predictions for James Webb Space Telescope (JWST) observations. While the present day GCs and UCDs are largely degenerate concerning bottom-heavy or top-heavy IMFs, a metallicity- and density-dependent top-heavy IMF implies the most massive UCDs, at ages < 100 Myr, to appear as objects with quasar-like luminosities with a 0.1-10% variability on a monthly timescale due to core collapse supernovae.
Midthune, Douglas; Dodd, Kevin W.; Freedman, Laurence S.; Krebs-Smith, Susan M.; Subar, Amy F.; Guenther, Patricia M.; Carroll, Raymond J.; Kipnis, Victor
2007-01-01
Objective We propose a new statistical method that uses information from two 24-hour recalls (24HRs) to estimate usual intake of episodically-consumed foods. Statistical Analyses Performed The method developed at the National Cancer Institute (NCI) accommodates the large number of non-consumption days that arise with foods by separating the probability of consumption from the consumption-day amount, using a two-part model. Covariates, such as sex, age, race, or information from a food frequency questionnaire (FFQ), may supplement the information from two or more 24HRs using correlated mixed model regression. The model allows for correlation between the probability of consuming a food on a single day and the consumption-day amount. Percentiles of the distribution of usual intake are computed from the estimated model parameters. Results The Eating at America's Table Study (EATS) data are used to illustrate the method to estimate the distribution of usual intake for whole grains and dark green vegetables for men and women and the distribution of usual intakes of whole grains by educational level among men. A simulation study indicates that the NCI method leads to substantial improvement over existing methods for estimating the distribution of usual intake of foods. Applications/Conclusions The NCI method provides distinct advantages over previously proposed methods by accounting for the correlation between probability of consumption and amount consumed and by incorporating covariate information. Researchers interested in estimating the distribution of usual intakes of foods for a population or subpopulation are advised to work with a statistician and incorporate the NCI method in analyses. PMID:17000190
The Optical Gravitational Lensing Experiment. Catalog of RRLyr Stars from the Small Magellanic Cloud
NASA Astrophysics Data System (ADS)
Soszynski, I.; Udalski, A.; Szymanski, M.; Kubiak, M.; Pietrzynski, G.; Wozniak, P.; Zebrun, K.; Szewczyk, O.; Wyrzykowski, L.
2002-12-01
We present the catalog of RRLyrae stars from 2.4 square degrees of central parts of the Small Magellanic Cloud (SMC). The photometric data were collected during four years of the OGLE-II microlensing survey. Photometry of each star was obtained using the Difference Image Analysis (DIA) method. The catalog contains 571 objects, including 458RRab, 56RRc variables, and 57 double mode RRLyr stars (RRd). Additionally we attach a list of variables with periods between 0.18-0.26 days, which are probably delta Sct stars. Period, BVI photometry, astrometry, amplitude, and parameters of the Fourier decomposition of the I-band light curve are provided for each object. We also present the Petersen diagram for double mode pulsators. We found that the SMC RRLyr stars are fairly uniformly distributed over the studied area, with no clear correlation to any location. The most preferred periods for RRab and RRc stars are 0.589 and 0.357 days, respectively. We noticed significant excess of stars with periods of about 0.29 days, which might be second-overtone RRLyr stars (RRe). The mean extinction free magnitudes derived for RRab stars are 18.97, 19.45 and 19.73 mag for the I, V and B-band, respectively. All presented data, including individual BVI observations, are available from the OGLE Internet archive.
Variability of the occurrence frequency of solar flares as a function of peak hard X-ray rate
NASA Technical Reports Server (NTRS)
Bai, T.
1993-01-01
We study the occurrence frequency of solar flares as a function of the hard X-ray peak count rate, using observations of the Solar Maximum Mission. The size distributions are well represented by power-law distributions with negative indices. As a better alternative to the conventional method, we devise a maximum likelihood method of determining the power-law index of the size distribution. We find that the power-law index of the size distribution changes with time and with the phase of the 154-day periodicity. The size distribution is steeper during the maximum years of solar cycle 21 (1980 and 1981) than during the declining phase (1982-1984). The size distribution, however, is flatter during the maximum phase of the 154-day periodicity than during the minimum phase. The implications of these findings are discussed.
Nguyen, Kyvan Q; Hawkins, Michelle G; Taylor, Ian T; Wiebe, Valerie J; Tell, Lisa A
2009-07-01
To determine the stability and distribution of voriconazole in 2 extemporaneously prepared (compounded) suspensions stored for 30 days at 2 temperatures. Voriconazole suspensions (40 mg/mL) compounded from commercially available 200-mg tablets suspended in 1 of 2 vehicles. One vehicle contained a commercially available suspending agent and a sweetening syrup in a 1:1 mixture (SASS). The other vehicle contained the suspending agent with deionized water in a 3:1 mixture (SADI). Voriconazole suspensions (40 mg/mL in 40-mL volumes) were compounded on day 0 and stored at room temperature (approx 21 degrees C) or refrigerated (approx 5 degrees C). To evaluate distribution, room-temperature aliquots of voriconazole were measured immediately after preparation. Refrigerated aliquots were measured after 3 hours of refrigeration. To evaluate stability, aliquots from each suspension were measured at approximately 7-day intervals for up to 30 days. Voriconazole concentration, color, odor, opacity, and pH were measured, and aerobic and anaerobic bacterial cultures were performed at various points. Drug distribution was uniform (coefficient of variation, < 5%) in both suspensions. On day 0, 87.8% to 93.0% of voriconazole was recovered; percentage recovery increased to between 95.1% and 100.8% by day 7. On subsequent days, up to day 30, percentage recovery was stable (> 90%) for all suspensions. The pH of each suspension did not differ significantly throughout the 30-day period. Storage temperature did not affect drug concentrations at any time, nor was bacterial growth obtained. Extemporaneously prepared voriconazole in SASS and SADI resulted in suspensions that remained stable for at least 30 days. Refrigerated versus room-temperature storage of the suspensions had no effect on drug stability.
NASA Astrophysics Data System (ADS)
Park, Jong-Hyeok; Kim, Ki-Beom; Chang, Heon-Young
2014-08-01
Time series of drought indices has been considered mostly in view of temporal and spatial distributions of a drought index so far. Here we investigate the statistical properties of a daily Effective Drought Index (EDI) itself for Seoul, Busan, Daegu, Mokpo for the period of 100 years from 1913 to 2012. We have found that both in dry and wet seasons the distribution of EDI as a function of EDI follows the Gaussian function. In dry season the shape of the Gaussian function is characteristically broader than that in wet seasons. The total number of drought days during the period we have analyzed is related both to the mean value and more importantly to the standard deviation. We have also found that according to the distribution of the number of occasions where the EDI values of several consecutive days are all less than a threshold, the distribution follows the exponential distribution. The slope of the best fit becomes steeper not only as the critical EDI value becomes more negative but also as the number of consecutive days increases. The slope of the exponential distribution becomes steeper as the number of the city in which EDI is simultaneously less than a critical EDI in a row increases. Finally, we conclude by pointing out implications of our findings.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Steinberg, Elad; Sari, Re’em
The Asteroid Belt and the Kuiper Belt are relics from the formation of our solar system. Understanding the size and spin distribution of the two belts is crucial for a deeper understanding of the formation of our solar system and the dynamical processes that govern it. In this paper, we investigate the effect of collisions on the evolution of the spin distribution of asteroids and KBOs. We find that the power law nature of the impactors’ size distribution leads to a Lévy distribution of the spin rates. This results in a power law tail in the spin distribution, in starkmore » contrast to the usually quoted Maxwellian distribution. We show that for bodies larger than 10 km, collisions alone lead to spin rates peaking at 0.15–0.5 revolutions per day. Comparing that to the observed spin rates of large asteroids (R > 50 km), we find that the spins of large asteroids, peaking at ∼1–2 revolutions per day, are dominated by a primordial component that reflects the formation mechanism of the asteroids. Similarly, the Kuiper Belt has undergone virtually no collisional spin evolution, assuming current densities. Collisions contribute a spin rate of ∼0.01 revolutions per day, thus the observed fast spin rates of KBOs are also primordial in nature.« less
Random-growth urban model with geographical fitness
NASA Astrophysics Data System (ADS)
Kii, Masanobu; Akimoto, Keigo; Doi, Kenji
2012-12-01
This paper formulates a random-growth urban model with a notion of geographical fitness. Using techniques of complex-network theory, we study our system as a type of preferential-attachment model with fitness, and we analyze its macro behavior to clarify the properties of the city-size distributions it predicts. First, restricting the geographical fitness to take positive values and using a continuum approach, we show that the city-size distributions predicted by our model asymptotically approach Pareto distributions with coefficients greater than unity. Then, allowing the geographical fitness to take negative values, we perform local coefficient analysis to show that the predicted city-size distributions can deviate from Pareto distributions, as is often observed in actual city-size distributions. As a result, the model we propose can generate a generic class of city-size distributions, including but not limited to Pareto distributions. For applications to city-population projections, our simple model requires randomness only when new cities are created, not during their subsequent growth. This property leads to smooth trajectories of city population growth, in contrast to other models using Gibrat’s law. In addition, a discrete form of our dynamical equations can be used to estimate past city populations based on present-day data; this fact allows quantitative assessment of the performance of our model. Further study is needed to determine appropriate formulas for the geographical fitness.
Epidemic of fractures during a period of snow and ice: has anything changed 33 years on?
Al-Azzani, Waheeb; Adam Maliq Mak, Danial; Hodgson, Paul; Williams, Rhodri
2016-09-14
We reproduced a frequently cited study that was published in the British Medical Journal (BMJ) in 1981 assessing the extent of 'snow-and-ice' fractures during the winter period. This study aims to provide an insight into how things have changed within the same emergency department (ED) by comparing the findings of the BMJ paper published 33 years ago with the present date. As per the original study, all patients presenting to the ED with a radiological evidence of fracture during three different 4-day periods were included. The three 4-day periods included 4 days of snow-and-ice conditions and two control 4-day periods when snow and ice was not present; the first was 4 days within the same year, with a similar amount of sunshine hours, and the second was 4 days 1 calendar year later. To identify the frequency, distribution and pattern of fractures sustained in snow-and-ice conditions compared to control conditions as well as comparisons with the index study 33 years ago. A total of 293 patients with fractures were identified. Overall, there was a 2.20 (CI 1.7 to 3.0, p <0.01) increase in risk of fracture during snow-and-ice periods compared to control conditions. There was an increase (p <0.01) of fractures of the arm, forearm and wrist (RR 3.2 (CI 1.4 to 7.6) and 2.9 (CI 1.5 to 5.4) respectively). While the relative risk was not of the magnitude 33 years ago, the overall number of patients presenting with a fracture during snow-and-ice conditions remains more than double compared to control conditions. This highlights the need for improved understanding of the impact of increased fracture burden on hospitals and more effective preventative measures. 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/
75 FR 56920 - Express Mail Open and Distribute and Priority Mail Open and Distribute
Federal Register 2010, 2011, 2012, 2013, 2014
2010-09-17
... POSTAL SERVICE 39 CFR Part 111 Express Mail Open and Distribute and Priority Mail Open and...] Open and Distribute containers. The Postal Service also proposes to revise the service commitment for Express Mail Open and Distribute as a guaranteed end of day product; and to add a five-pound minimum...
Virlogeux, Victor; Li, Ming; Tsang, Tim K; Feng, Luzhao; Fang, Vicky J; Jiang, Hui; Wu, Peng; Zheng, Jiandong; Lau, Eric H Y; Cao, Yu; Qin, Ying; Liao, Qiaohong; Yu, Hongjie; Cowling, Benjamin J
2015-10-15
A novel avian influenza virus, influenza A(H7N9), emerged in China in early 2013 and caused severe disease in humans, with infections occurring most frequently after recent exposure to live poultry. The distribution of A(H7N9) incubation periods is of interest to epidemiologists and public health officials, but estimation of the distribution is complicated by interval censoring of exposures. Imputation of the midpoint of intervals was used in some early studies, resulting in estimated mean incubation times of approximately 5 days. In this study, we estimated the incubation period distribution of human influenza A(H7N9) infections using exposure data available for 229 patients with laboratory-confirmed A(H7N9) infection from mainland China. A nonparametric model (Turnbull) and several parametric models accounting for the interval censoring in some exposures were fitted to the data. For the best-fitting parametric model (Weibull), the mean incubation period was 3.4 days (95% confidence interval: 3.0, 3.7) and the variance was 2.9 days; results were very similar for the nonparametric Turnbull estimate. Under the Weibull model, the 95th percentile of the incubation period distribution was 6.5 days (95% confidence interval: 5.9, 7.1). The midpoint approximation for interval-censored exposures led to overestimation of the mean incubation period. Public health observation of potentially exposed persons for 7 days after exposure would be appropriate. © The Author 2015. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Spatial and temporal oxygen isotope trends at the northern tree-line in Eurasia
NASA Astrophysics Data System (ADS)
Saurer, Matthias; Schweingruber, Fritz; Vaganov, Eugene A.; Shiyatov, Stepan G.; Siegwolf, Rolf
2002-05-01
The oxygen isotope ratio of ice cores and sea-sediments is an extremely useful source of information on long-term climatic changes. A similar approach has been applied to the oxygen isotope ratio of tree rings to enable a pattern-based reconstruction of the isotope variations on the continents. We present an oxygen isotope map for northern Eurasia spanning from Norway to Siberia, that reflects the isotope distribution in the late 19th century, and compare it with an equivalent map for the present-day situation. The average isotope values of 130 trees show a large east-to-west gradient and are highly correlated with the isotope distribution of precipitation. Surprisingly, the 18O/16O ratio of the wood has been decreasing in the interior of the continent since the late 19th century, in contrast to the strong temperature increase recorded by meteorological data. From this isotope trend over time a change in the seasonality of precipitation can be inferred.
Smart grid integration of small-scale trigeneration systems
NASA Astrophysics Data System (ADS)
Vacheva, Gergana; Kanchev, Hristiyan; Hinov, Nikolay
2017-12-01
This paper presents a study on the possibilities for implementation of local heating, air-conditioning and electricity generation (trigeneration) as distributed energy resource in the Smart Grid. By the means of microturbine-based generators and absorption chillers buildings are able to meet partially or entirely their electrical load curve or even supply power to the grid by following their heating and air-conditioning daily schedule. The principles of small-scale cooling, heating and power generation systems are presented at first, then the thermal calculations of an example building are performed: the heat losses due to thermal conductivity and the estimated daily heating and air-conditioning load curves. By considering daily power consumption curves and weather data for several winter and summer days, the heating/air-conditioning schedule is estimated and the available electrical energy from a microturbine-based cogeneration system is estimated. Simulation results confirm the potential of using cogeneration and trigeneration systems for local distributed electricity generation and grid support in the daily peaks of power consumption.
Adeniran, A E; Nubi, A T; Adelopo, A O
2017-09-01
Waste characterization is the first step to any successful waste management policy. In this paper, the characterization and the trend of solid waste generated in University of Lagos, Nigeria was carried out using ASTM D5231-92 and Resource Conservation Reservation Authority RCRA Waste Sampling Draft Technical Guidance methods. The recyclable potential of the waste is very high constituting about 75% of the total waste generated. The estimated average daily solid waste generation in Unilag Akoka campus was estimated to be 32.2tons. The solid waste characterization was found to be: polythene bags 24% (7.73tons/day), paper 15% (4.83tons/day), organic matters 15%, (4.83tons/day), plastic 9% (2.90tons/day), inert materials 8% (2.58tons/day), sanitary 7% (2.25tons/day), textile 7% (2.25tons/day), others 6% (1.93tons/day), leather 4% (1.29tons/day) metals 3% (0.97tons/day), glass 2% (0.64tons/day) and e-waste 0% (0.0tons/day). The volume and distribution of polythene bags generated on campus had a positive significant statistical correlation with the distribution of commercial and academic structures on campus. Waste management options to optimize reuse, recycling and reduce waste generation were discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.
Code of Federal Regulations, 2010 CFR
2010-07-01
... Facility (SCF) turnaround Standard Mail® pieces accepted at origin before the day zero Critical Entry Time... origin before the day zero Critical Entry Time is 4 days when the OPD&C/F and the ADC are the same... intra-Network Distribution Center (NDC) Standard Mail pieces accepted at origin before the day-zero...
Code of Federal Regulations, 2011 CFR
2011-07-01
... Facility (SCF) turnaround Standard Mail® pieces accepted at origin before the day zero Critical Entry Time... origin before the day zero Critical Entry Time is 4 days when the OPD&C/F and the ADC are the same... intra-Network Distribution Center (NDC) Standard Mail pieces accepted at origin before the day-zero...
Sodium Atoms in the Lunar Exotail: Observed Velocity and Spatial Distributions
NASA Technical Reports Server (NTRS)
Line, Michael R.; Mierkiewicz, E. J.; Oliversen, R. J.; Wilson, J. K.; Haffner, L. M.; Roesler, F. L.
2011-01-01
The lunar sodium tail extends long distances due to radiation pressure on sodium atoms in the lunar exosphere. Our earlier observations determined the average radial velocity of sodium atoms moving down the lunar tail beyond Earth along the Sun-Moon-Earth line (i.e., the anti-lunar point) to be 12.4 km/s. Here we use the Wisconsin H-alpha Mapper to obtain the first kinematically resolved maps of the intensity and velocity distribution of this emission over a 15 x times 15 deg region on the sky near the anti-lunar point. We present both spatially and spectrally resolved observations obtained over four nights around new moon in October 2007. The spatial distribution of the sodium atoms is elongated along the ecliptic with the location of the peak intensity drifting 3 degrees east along the ecliptic per night. Preliminary modeling results suggest that the spatial and velocity distributions in the sodium exotail are sensitive to the near surface lunar sodium velocity distribution and that observations of this sort along with detailed modeling offer new opportunities to describe the time history of lunar surface sputtering over several days.
Post-traumatic acute kidney injury: a cross-sectional study of trauma patients.
Lai, Wei-Hung; Rau, Cheng-Shyuan; Wu, Shao-Chun; Chen, Yi-Chun; Kuo, Pao-Jen; Hsu, Shiun-Yuan; Hsieh, Ching-Hua; Hsieh, Hsiao-Yun
2016-11-22
The causes of post-traumatic acute kidney injury (AKI) are multifactorial, and shock associated with major trauma has been proposed to result in inadequate renal perfusion and subsequent AKI in trauma patients. This study aimed to investigate the true incidence and clinical presentation of post-traumatic AKI in hospitalized adult patients and its association with shock at a Level I trauma center. Detailed data of 78 trauma patients with AKI and 14,504 patients without AKI between January 1, 2009 and December 31, 2014 were retrieved from the Trauma Registry System. Patients with direct renal trauma were excluded from this study. Two-sided Fisher's exact or Pearson's chi-square tests were used to compare categorical data, unpaired Student's t-test was used to analyze normally distributed continuous data, and Mann-Whitney's U test was used to compare non-normally distributed data. Propensity score matching with a 1:1 ratio with logistic regression was used to evaluate the effect of shock on AKI. Patients with AKI presented with significantly older age, higher incidence rates of pre-existing comorbidities, higher odds of associated injures (subdural hematoma, intracerebral hematoma, intra-abdominal injury, and hepatic injury), and higher injury severity than patients without AKI. In addition, patients with AKI had a longer hospital stay (18.3 days vs. 9.8 days, respectively; P < 0.001) and intensive care unit (ICU) stay (18.8 days vs. 8.6 days, respectively; P < 0. 001), higher proportion of admission into the ICU (57.7% vs. 19.0%, respectively; P < 0.001), and a higher odds ratio (OR) of short-term mortality (OR 39.0; 95% confidence interval, 24.59-61.82; P < 0.001). However, logistic regression analysis of well-matched pairs after propensity score matching did not show a significant influence of shock on the occurrence of AKI. We believe that early and aggressive resuscitation, to avoid prolonged untreated shock, may help to prevent the occurrence of post-traumatic AKI. However, more evidence is required to support this observation. Compared to patients without AKI, patients with AKI presented with different injury characteristics and worse outcome. However, an association between shock and post-traumatic AKI could not be identified.
Contact Patterns among High School Students
Fournet, Julie; Barrat, Alain
2014-01-01
Face-to-face contacts between individuals contribute to shape social networks and play an important role in determining how infectious diseases can spread within a population. It is thus important to obtain accurate and reliable descriptions of human contact patterns occurring in various day-to-day life contexts. Recent technological advances and the development of wearable sensors able to sense proximity patterns have made it possible to gather data giving access to time-varying contact networks of individuals in specific environments. Here we present and analyze two such data sets describing with high temporal resolution the contact patterns of students in a high school. We define contact matrices describing the contact patterns between students of different classes and show the importance of the class structure. We take advantage of the fact that the two data sets were collected in the same setting during several days in two successive years to perform a longitudinal analysis on two very different timescales. We show the high stability of the contact patterns across days and across years: the statistical distributions of numbers and durations of contacts are the same in different periods, and we observe a very high similarity of the contact matrices measured in different days or different years. The rate of change of the contacts of each individual from one day to the next is also similar in different years. We discuss the interest of the present analysis and data sets for various fields, including in social sciences in order to better understand and model human behavior and interactions in different contexts, and in epidemiology in order to inform models describing the spread of infectious diseases and design targeted containment strategies. PMID:25226026
Inverse statistics in the foreign exchange market
NASA Astrophysics Data System (ADS)
Jensen, M. H.; Johansen, A.; Petroni, F.; Simonsen, I.
2004-09-01
We investigate intra-day foreign exchange (FX) time series using the inverse statistic analysis developed by Simonsen et al. (Eur. Phys. J. 27 (2002) 583) and Jensen et al. (Physica A 324 (2003) 338). Specifically, we study the time-averaged distributions of waiting times needed to obtain a certain increase (decrease) ρ in the price of an investment. The analysis is performed for the Deutsch Mark (DM) against the US for the full year of 1998, but similar results are obtained for the Japanese Yen against the US. With high statistical significance, the presence of “resonance peaks” in the waiting time distributions is established. Such peaks are a consequence of the trading habits of the market participants as they are not present in the corresponding tick (business) waiting time distributions. Furthermore, a new stylized fact, is observed for the (normalized) waiting time distribution in the form of a power law Pdf. This result is achieved by rescaling of the physical waiting time by the corresponding tick time thereby partially removing scale-dependent features of the market activity.
Accessing NASA Technology with the World Wide Web
NASA Technical Reports Server (NTRS)
Nelson, Michael L.; Bianco, David J.
1995-01-01
NASA Langley Research Center (LaRC) began using the World Wide Web (WWW) in the summer of 1993, becoming the first NASA installation to provide a Center-wide home page. This coincided with a reorganization of LaRC to provide a more concentrated focus on technology transfer to both aerospace and non-aerospace industry. Use of WWW and NCSA Mosaic not only provides automated information dissemination, but also allows for the implementation, evolution and integration of many technology transfer and technology awareness applications. This paper describes several of these innovative applications, including the on-line presentation of the entire Technology OPportunities Showcase (TOPS), an industrial partnering showcase that exists on the Web long after the actual 3-day event ended. The NASA Technical Report Server (NTRS) provides uniform access to many logically similar, yet physically distributed NASA report servers. WWW is also the foundation of the Langley Software Server (LSS), an experimental software distribution system which will distribute LaRC-developed software. In addition to the more formal technology distribution projects, WWW has been successful in connecting people with technologies and people with other people.
2009-01-01
1 DISTRIBUTION STATEMENT A: Approved for public release; distribution is unlimited. Studies of Ionospheric Plasma Structuring at Low...program combines observations and modeling of the nighttime ionosphere to come to a better physical understanding of the factors that contribute to...the day-to-day variability of the development of ionospheric irregularities. The scope encompasses irregularities developing at equatorial and mid
Winds and the distribution of nearshore phytoplankton in a stratified lake.
Cyr, Hélène
2017-10-01
The distribution of phytoplankton in lakes is notoriously patchy and dynamic, but wind-driven currents and algal buoyancy/motility are thought to determine where algae accumulate. In this study, nearshore phytoplankton were sampled from different parts of a lake basin twice a day for 4-5 consecutive days, in the spring and in late summer, to test whether short-term changes in phytoplankton biomass and community composition can be predicted from wind-driven currents. On windy days, phytoplankton biomass was higher at downwind than at upwind nearshore sites, and the magnitude of this difference increased linearly with increasing wind speed. However, contrary to the generally assumed downwind phytoplankton aggregations, these differences were mostly due to upwelling activity and the dilution of phytoplankton at upwind nearshore sites. The distribution of individual taxa was also related to wind speed, but only during late stratification (except for cryptophytes), and these relationships were consistent with the buoyancy and motility of each group. On windy days, large diatoms and cyanobacteria concentrated upwind, neutrally buoyant taxa (green algae, small diatoms) were homogeneously distributed, and motile taxa (cryptophytes, chrysophytes, dinoflagellates) concentrated downwind. Predictable differences in the biomass and composition of phytoplankton communities could affect the efficiency of trophic transfers in nearshore areas. Copyright © 2017 Elsevier Ltd. All rights reserved.
Rigét, Frank F.; Kyhn, Line A.; Sveegaard, Signe; Dietz, Rune; Tougaard, Jakob; Carlström, Julia A. K.; Carlén, Ida; Koblitz, Jens C.; Teilmann, Jonas
2016-01-01
Cetacean monitoring is essential in determining the status of a population. Different monitoring methods should reflect the real trends in abundance and patterns in distribution, and results should therefore ideally be independent of the selected method. Here, we compare two independent methods of describing harbour porpoise (Phocoena phocoena) relative distribution pattern in the western Baltic Sea. Satellite locations from 13 tagged harbour porpoises were used to build a Maximum Entropy (MaxEnt) model of suitable habitats. The data set was subsampled to one location every second day, which were sufficient to make reliable models over the summer (Jun-Aug) and autumn (Sep-Nov) seasons. The modelled results were compared to harbour porpoise acoustic activity obtained from 36 static acoustic monitoring stations (C-PODs) covering the same area. The C-POD data was expressed as the percentage of porpoise positive days/hours (the number of days/hours per day with porpoise detections) by season. The MaxEnt model and C-POD data showed a significant linear relationship with a strong decline in porpoise occurrence from west to east. This study shows that two very different methods provide comparable information on relative distribution patterns of harbour porpoises even in a low density area. PMID:27463509
NASA Astrophysics Data System (ADS)
Wicks, L. C.; Gardner, J. P. A.; Davy, S. K.
2012-06-01
Tolerance of environmental variables differs between corals and their dinoflagellate symbionts ( Symbiodinium spp.), controlling the holobiont's (host and symbiont combined) resilience to environmental stress. However, the ecological role that environmental variables play in holobiont distribution remains poorly understood. We compared the drivers of symbiont and coral species distributions at Palmyra Atoll, a location with a range of reef environments from low to high sediment concentrations (1-52 g dry weight m-2 day-1). We observed uniform holobiont partnerships across the atoll (e.g. Montipora spp. with Symbiodinium type C15 at all sites). Multivariate analysis revealed that field-based estimates of settling sediment predominantly explained the spatial variation of coral species among sites ( P < 0.01). However, none of the environmental variables measured (sedimentation, temperature, chlorophyll concentration, salinity) affected symbiont distribution. The discord between environmental variables and symbiont distributions suggests that the symbionts are physiologically tolerant of the variable environmental regime across this location and that the distribution of different host-symbiont combinations present is largely dependent on coral rather than Symbiodinium physiology. The data highlight the importance of host tolerance to environmental stressors, which should be considered simultaneously with symbiont sensitivity when considering the impact of variations in environmental conditions on coral communities.
Detecting daily routines of older adults using sensor time series clustering.
Hajihashemi, Zahra; Yefimova, Maria; Popescu, Mihail
2014-01-01
The aim of this paper is to develop an algorithm to identify deviations in patterns of day-to-day activities of older adults to generate alerts to the healthcare providers for timely interventions. Daily routines, such as bathroom visits, can be monitored by automated in-home sensor systems. We present a novel approach that finds periodicity in sensor time series data using clustering approach. For this study, we used data set from TigerPlace, a retirement community in Columbia, MO, where apartments are equipped with a network of motion, pressure and depth sensors. A retrospective multiple case study (N=3) design was used to quantify bathroom visits as parts of the older adult's daily routine, over a 10-day period. The distribution of duration, number, and average time between sensor hits was used to define the confidence level for routine visit extraction. Then, a hierarchical clustering was applied to extract periodic patterns. The performance of the proposed method was evaluated through experimental results.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Greenlaw, P.D.
1998-12-01
This Quality Assessment Program (QAP) is designed to test the quality of the environmental measurements being reported to the Department of Energy by its contractors. Since 1976, real or synthetic environmental samples that have been prepared and thoroughly analyzed at the Environmental measurements Laboratory (EML) have been distributed at first quarterly and then semi-annually to these contractors. Their results, which are returned to EML within 90 days, are compiled with EML`s results and are reported back to the participating contractors 30 days later. A summary of the reported results is available to the participants 4 days after the reporting deadlinemore » via the Internet at www.eml.doe.gov. This report presents the results from the analysis of the 49th set of environmental quality assessment samples (QAP XLIX) that were received on or before December 1, 1998.« less
NASA Astrophysics Data System (ADS)
Zhu, Zhiwei; Li, Tim
2017-01-01
The extended-range (10-30-day) rainfall forecast over the entire China was carried out using spatial-temporal projection models (STPMs). Using a rotated empirical orthogonal function analysis of intraseasonal (10-80-day) rainfall anomalies, China is divided into ten sub-regions. Different predictability sources were selected for each of the ten regions. The forecast skills are ranked for each region. Based on temporal correlation coefficient (TCC) and Gerrity skill score, useful skills are found for most parts of China at a 20-25-day lead. The southern China and the mid-lower reaches of Yangtze River Valley show the highest predictive skills, whereas southwestern China and Huang-Huai region have the lowest predictive skills. By combining forecast results from ten regional STPMs, the TCC distribution of 8-year (2003-2010) independent forecast for the entire China is investigated. The combined forecast results from ten STPMs show significantly higher skills than the forecast with just one single STPM for the entire China. Independent forecast examples of summer rainfall anomalies around the period of Beijing Olympic Games in 2008 and Shanghai World Expo in 2010 are presented. The result shows that the current model is able to reproduce the gross pattern of the summer intraseasonal rainfall over China at a 20-day lead. The present study provides, for the first time, a guide on the statistical extended-range forecast of summer rainfall anomalies for the entire China. It is anticipated that the ideas and methods proposed here will facilitate the extended-range forecast in China.
Redox gradients in distribution systems influence water quality, corrosion, and microbial ecology.
Masters, Sheldon; Wang, Hong; Pruden, Amy; Edwards, Marc A
2015-01-01
Simulated distribution systems (SDSs) defined the interplay between disinfectant type (free chlorine and chloramines), water age (1-10.2 days), and pipe material (PVC, iron and cement surfaces) on water chemistry, redox zones and infrastructure degradation. Redox gradients developed as a function of water age and pipe material affected the quality of water consumers would receive. Free chlorine was most stable in the presence of PVC while chloramine was most stable in the presence of cement. At a 3.6 day water age the residual in the chlorinated PVC SDS was more than 3.5 times higher than in the chlorinated iron or cement systems. In contrast, the residual in the chloraminated cement SDS was more than 10 times greater than in the chloraminated iron or PVC systems. Near the point of entry to the SDSs where disinfectant residuals were present, free chlorine tended to cause as much as 4 times more iron corrosion when compared to chloramines. Facultative denitrifying bacteria were ubiquitous, and caused complete loss of nitrogen at distal points in systems with iron, and these bacteria co-occurred with very severe pitting attack (1.6-1.9 mm/year) at high water age.
Roué, Mélanie; Darius, Hélène Taiana; Ung, André; Viallon, Jérôme; Sibat, Manoella; Hess, Philipp; Amzil, Zouher; Chinain, Mireille
2018-05-10
Ciguatera is a foodborne disease caused by the consumption of seafood contaminated with ciguatoxins (CTXs). Ciguatera-like poisoning events involving giant clams ( Tridacna maxima ) are reported occasionally from Pacific islands communities. The present study aimed at providing insights into CTXs tissue distribution and detoxification rate in giant clams exposed to toxic cells of Gambierdiscus polynesiensis , in the framework of seafood safety assessment. In a first experiment, three groups of tissue (viscera, flesh and mantle) were dissected from exposed individuals, and analyzed for their toxicity using the neuroblastoma cell-based assay (CBA-N2a) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analyses. The viscera, flesh, and mantle were shown to retain 65%, 25%, and 10% of the total toxin burden, respectively. All tissues reached levels above the safety limit recommended for human consumption, suggesting that evisceration alone, a practice widely used among local populations, is not enough to ensure seafood safety. In a second experiment, the toxin content in contaminated giant clams was followed at different time points (0, 2, 4, and 6 days post-exposure). Observations suggest that no toxin elimination is visible in T. maxima throughout 6 days of detoxification.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lee, Eve J.; Chiang, Eugene, E-mail: evelee@berkeley.edu
Sub-Neptunes around FGKM dwarfs are evenly distributed in log orbital period down to ∼10 days, but dwindle in number at shorter periods. Both the break at ∼10 days and the slope of the occurrence rate down to ∼1 day can be attributed to the truncation of protoplanetary disks by their host star magnetospheres at corotation. We demonstrate this by deriving planet occurrence rate profiles from empirical distributions of pre-main-sequence stellar rotation periods. Observed profiles are better reproduced when planets are distributed randomly in disks—as might be expected if planets formed in situ—rather than piled up near disk edges, as wouldmore » be the case if they migrated in by disk torques. Planets can be brought from disk edges to ultra-short (<1 day) periods by asynchronous equilibrium tides raised on their stars. Tidal migration can account for how ultra-short-period planets are more widely spaced than their longer-period counterparts. Our picture provides a starting point for understanding why the sub-Neptune population drops at ∼10 days regardless of whether the host star is of type FGK or early M. We predict planet occurrence rates around A stars to also break at short periods, but at ∼1 day instead of ∼10 days because A stars rotate faster than stars with lower masses (this prediction presumes that the planetesimal building blocks of planets can drift inside the dust sublimation radius).« less
Mata, Rani; Nakkala, Jayachandra Reddy; Chandra, Varshney Khub; Raja, Kumar; Sadras, Sudha Rani
2018-07-01
This study reports the bio-distribution and clearance of Abutilon indicum silver and gold nanoparticles (AIAgNPs and AIAuNPs) in Wistar rats. Rats in different groups were orally administered with 5 and 10 mg/Kg BW of AIAgNPs and AIAuNPs (size 1-25 nm) for 28 days and few were maintained until 58 days of washout period. Serum biochemical parameters were not changed significantly at both doses of AIAuNPs and at lower concentration of AIAgNPs. But, with 10 mg/Kg BW of AIAgNPs rats showed elevated levels of AST, ALP and ALT on day 29, however, these levels were restored to normal after washout period. Liver oxidative stress markers were not altered with the treatment of AIAgNPs and AIAuNPs. ICP-OES analysis indicated bio-distribution of Ag and Au more in liver, kidney and spleen on day 29 and was found cleared on day 59. Histological analysis of nine vital organs indicated normal tissue architecture at both doses of AIAuNPs and lower dose of AIAgNPs. While the rats treated with higher dose of AIAgNPs showed mild liver sinusoid cell swelling on day 29, which also was recovered on day 59. Findings of this preclinical study indicate biocompatible nature of biogenic nanoparticles supporting their future biomedical applications. Copyright © 2018 Elsevier GmbH. All rights reserved.
Kip, Anke E; Castro, María Del Mar; Gomez, Maria Adelaida; Cossio, Alexandra; Schellens, Jan H M; Beijnen, Jos H; Saravia, Nancy Gore; Dorlo, Thomas P C
2018-05-10
Leishmania parasites reside within macrophages and the direct target of antileishmanial drugs is therefore intracellular. We aimed to characterize the intracellular PBMC miltefosine kinetics by developing a population pharmacokinetic (PK) model simultaneously describing plasma and intracellular PBMC pharmacokinetics. Furthermore, we explored exposure-response relationships and simulated alternative dosing regimens. A population PK model was developed with NONMEM, based on 339 plasma and 194 PBMC miltefosine concentrations from Colombian cutaneous leishmaniasis patients [29 children (2-12 years old) and 22 adults] receiving 1.8-2.5 mg/kg/day miltefosine for 28 days. A three-compartment model with miltefosine distribution into an intracellular PBMC effect compartment best fitted the data. Intracellular PBMC distribution was described with an intracellular-to-plasma concentration ratio of 2.17 [relative standard error (RSE) 4.9%] and intracellular distribution rate constant of 1.23 day-1 (RSE 14%). In exploring exposure-response relationships, both plasma and intracellular model-based exposure estimates significantly influenced probability of cure. A proposed PK target for the area under the plasma concentration-time curve (day 0-28) of >535 mg·day/L corresponded to >95% probability of cure. In linear dosing simulations, 18.3% of children compared with 2.8% of adults failed to reach 535 mg·day/L. In children, this decreased to 1.8% after allometric dosing simulation. The developed population PK model described the rate and extent of miltefosine distribution from plasma into PBMCs. Miltefosine exposure was significantly related to probability of cure in this cutaneous leishmaniasis patient population. We propose an exploratory PK target, which should be validated in a larger cohort study.
NASA Astrophysics Data System (ADS)
Alvares, Clayton Alcarde; Sentelhas, Paulo César; Stape, José Luiz
2017-09-01
Although Brazil is predominantly a tropical country, frosts are observed with relative high frequency in the Center-Southern states of the country, affecting mainly agriculture, forestry, and human activities. Therefore, information about the frost climatology is of high importance for planning of these activities. Based on that, the aims of the present study were to develop monthly meteorological (F MET) and agronomic (F AGR) frost day models, based on minimum shelter air temperature (T MN), in order to characterize the temporal and spatial frost days variability in Center-Southern Brazil. Daily minimum air temperature data from 244 weather stations distributed across the study area were used, being 195 for developing the models and 49 for validating them. Multivariate regression models were obtained to estimate the monthly T MN, once the frost day models were based on this variable. All T MN regression models were statistically significant (p < 0.001), presenting adjusted R 2 between 0.69 and 0.90. Center-Southern Brazil is mainly hit by frosts from mid-fall (April) to mid-spring (October). The period from November to March is considered as frost-free, being very rare a frost day within that period. Monthly F MET and F AGR presented significant sigmoidal relationships with T MN (p < 0.0001), with adjusted R 2 above of 0.82. The residuals of the frost day models were random, which means that the sigmoidal models performed quite well for interpreting the frost day variability throughout the study area. The highlands of Santa Catarina, Rio Grande do Sul, São Paulo, and Minas Gerais had in average more than 25 and 13 frosts per year, respectively, for F MET and F AGR. The F MET and F AGR maps developed in this study for Center-Southern Brazil is a useful tool for farmers, foresters, and researchers, since they contribute to reduce frost spatial and temporal uncertainty, helping in planning project for strategic purposes. Furthermore, the monthly F MET and F AGR maps for this Brazilian region are the first zoning of these variables for the country.
Electron pitch angle distributions throughout the magnetosphere as observed on Ogo 5.
NASA Technical Reports Server (NTRS)
West, H. I., Jr.; Buck, R. M.; Walton, J. R.
1973-01-01
A survey of the equatorial pitch angle distributions of energetic electrons is provided for all local times out to radial distances of 20 earth radii on the night side of the earth and to the magnetopause on the day side of the earth. In much of the inner magnetosphere and in the outer magnetosphere on the day side of the earth, the normal loss cone distribution prevails. The effects of drift shell splitting - i.e., the appearance of pitch angle distributions with minimums at 90 deg, called butterfly distributions - become apparent in the early afternoon magnetosphere at extended distances, and the distribution is observed in to 5.5 earth radii in the nighttime magnetosphere. Inside about 9 earth radii the pitch angle effects are quite energy-dependent. Beyond about 9 earth radii in the premidnight magnetosphere during quiet times the butterfly distribution is often observed. It is shown that these electrons cannot survive a drift to dawn without being considerably modified. The role of substorm activity in modifying these distributions is identified.
Statistical dynamics of regional populations and economies
NASA Astrophysics Data System (ADS)
Huo, Jie; Wang, Xu-Ming; Hao, Rui; Wang, Peng
Quantitative analysis of human behavior and social development is becoming a hot spot of some interdisciplinary studies. A statistical analysis on the population and GDP of 150 cities in China from 1990 to 2013 is conducted. The result indicates the cumulative probability distribution of the populations and that of the GDPs obeying the shifted power law, respectively. In order to understand these characteristics, a generalized Langevin equation describing variation of population is proposed, which is based on the correlations between population and GDP as well as the random fluctuations of the related factors. The equation is transformed into the Fokker-Plank equation to express the evolution of population distribution. The general solution demonstrates a transition of the distribution from the normal Gaussian distribution to a shifted power law, which suggests a critical point of time at which the transition takes place. The shifted power law distribution in the supercritical situation is qualitatively in accordance with the practical result. The distribution of the GDPs is derived from the well-known Cobb-Douglas production function. The result presents a change, in supercritical situation, from a shifted power law to the Gaussian distribution. This is a surprising result-the regional GDP distribution of our world will be the Gaussian distribution one day in the future. The discussions based on the changing trend of economic growth suggest it will be true. Therefore, these theoretical attempts may draw a historical picture of our society in the aspects of population and economy.
Chippaux, J-P; Diouf, A; Massougbodji, A; Stock, R P; Kane, O; Dièye, A M; Lam Faye, A; Mbaye Sène, M; Parra, H-J
2012-08-01
The authors present a summary of the proceedings and the recommendations of the Fourth International Conference on Envenomations by Snakebites and Scorpion Stings in Africa, held from 25 to 29 April 2011 in Dakar. After a two-day workshop for Senegalese health personnel on the most relevant aspects of the management of envenomations, about 270 participants met to share their experiences in the field. Nearly a hundred oral and poster presentations were made on the epidemiology of snakebites and scorpion stings in Africa, the composition and action of venoms and the manufacture and use of antivenoms. The last day was devoted to an institutional debate involving experts, representatives of national health authorities and concerned professionals (physicians, pharmacists, nurses and traditional healers) as well as members of the pharmaceutical industry to discuss and elaborate a set of recommendations. It was agreed that it is necessary to improve knowledge of the epidemiological situation by case reporting. Quality control of antivenoms and procedures for their registration at the level of national health authorities should aim at improving the distribution of safe and effective antivenoms in peripheral health centers for the better assessment of victims. It was also recommended that adequate training should be provided for health personnel in all aspects of medical management of envenomations. Equitable distribution of funding and the establishment of a network of African experts were also discussed in the conference.
NASA Astrophysics Data System (ADS)
Li, Angang; Reidenbach, Matthew A.
2014-09-01
Elevated sea surface temperature (SST) caused by global warming is one of the major threats to coral reefs. While increased SST has been shown to negatively affect the health of coral reefs by increasing rates of coral bleaching, how changes to atmospheric heating impact SST distributions, modified by local flow environments, has been less understood. This study aimed to simulate future water flow patterns and water surface heating in response to increased air temperature within a coral reef system in Bocas del Toro, Panama, located within the Caribbean Sea. Water flow and SST were modeled using the Delft3D-FLOWcomputer simulation package. Locally measured physical parameters, including bathymetry, astronomic tidal forcing, and coral habitat distribution were input into the model and water flow, and SST was simulated over a four-month period under present day, as well as projected warming scenarios in 2020s, 2050s, and 2080s. Changes in SST, and hence the thermal stress to corals, were quantified by degree heating weeks. Results showed that present-day reported bleaching sites were consistent with localized regions of continuous high SST. Regions with highest SST were located within shallow coastal sites adjacent to the mainland or within the interior of the bay, and characterized by low currents with high water retention times. Under projected increases in SSTs, shallow reef areas in low flow regions were found to be hot spots for future bleaching.
A remote sensing study of active folding and faulting in southern Kerman province, S.E. Iran
NASA Astrophysics Data System (ADS)
Walker, Richard Thomas
2006-04-01
Geomorphological observations reveal a major oblique fold-and-thrust belt in Kerman province, S.E. Iran. The active faults appear to link the Sabzevaran right-lateral strike-slip fault in southeast Iran to other strike-slip faults within the interior of the country and may provide the means of distributing right-lateral shear between the Zagros and Makran mountains over a wider region of central Iran. The Rafsanjan fault is manifest at the Earth's surface as right-lateral strike-slip fault scarps and folding in alluvial sediments. Height changes across the anticlines, and widespread incision of rivers, are likely to result from hanging-wall uplift above thrust faults at depth. Scarps in recent alluvium along the northern margins of the folds suggest that the thrusts reach the surface and are active at the present-day. The observations from Rafsanjan are used to identify similar late Quaternary faulting elsewhere in Kerman province near the towns of Mahan and Rayen. No instrumentally recorded destructive earthquakes have occurred in the study region and only one historical earthquake (Lalehzar, 1923) is recorded. In addition GPS studies show that present-day rates of deformation are low. However, fault structures in southern Kerman province do appear to be active in the late Quaternary and may be capable of producing destructive earthquakes in the future. This study shows how widely available remote sensing data can be used to provide information on the distribution of active faulting across large areas of deformation.
Tchaicka, Ligia; de Freitas, Thales Renato Ochotorena; Bager, Alex; Vidal, Stela Luengos; Lucherini, Mauro; Iriarte, Agustín; Novaro, Andres; Geffen, Eli; Garcez, Fabricio Silva; Johnson, Warren E.; Wayne, Robert K.; Eizirik, Eduardo
2016-01-01
Abstract To investigate the evolution and biogeography of an endemic group of South American foxes, we examined mitochondrial DNA control region sequences for 118 individuals belonging to all six extant species of the genus Lycalopex. Phylogenetic and molecular dating analyses supported the inference that this genus has undergone a very recent and rapid radiation, stemming from a common ancestor that lived ca. 1 million years ago. The Brazilian endemic L. vetulus was supported as the most basal species in this genus, whereas the most internal group is comprised by the recently diverged (ca. 350,000 years ago) Andean/Patagonian species L. griseus and L. culpaeus. We discuss the inferred phylogenetic relationships and divergence times in the context of the current geographic distributions of these species, and the likely effects of Pleistocene climatic changes on the biogeography of this group. Furthermore, a remarkable finding was the identification of multiple individuals classified as L. gymnocercus bearing mtDNA haplotypes clearly belonging to L. griseus, sampled in regions where the latter is not known to occur. At a minimum, this result implies the need to clarify the present-day geographic distribution of each of these fox species, while it may also indicate an ongoing hybridization process between them. Future testing of this hypothesis with in-depth analyses of these populations is thus a priority for understanding the history, evolutionary dynamics and present-day composition of this endemic Neotropical genus. PMID:27560989
Tchaicka, Ligia; Freitas, Thales Renato Ochotorena de; Bager, Alex; Vidal, Stela Luengos; Lucherini, Mauro; Iriarte, Agustín; Novaro, Andres; Geffen, Eli; Garcez, Fabricio Silva; Johnson, Warren E; Wayne, Robert K; Eizirik, Eduardo
2016-01-01
To investigate the evolution and biogeography of an endemic group of South American foxes, we examined mitochondrial DNA control region sequences for 118 individuals belonging to all six extant species of the genus Lycalopex. Phylogenetic and molecular dating analyses supported the inference that this genus has undergone a very recent and rapid radiation, stemming from a common ancestor that lived ca. 1 million years ago. The Brazilian endemic L. vetulus was supported as the most basal species in this genus, whereas the most internal group is comprised by the recently diverged (ca. 350,000 years ago) Andean/Patagonian species L. griseus and L. culpaeus. We discuss the inferred phylogenetic relationships and divergence times in the context of the current geographic distributions of these species, and the likely effects of Pleistocene climatic changes on the biogeography of this group. Furthermore, a remarkable finding was the identification of multiple individuals classified as L. gymnocercus bearing mtDNA haplotypes clearly belonging to L. griseus, sampled in regions where the latter is not known to occur. At a minimum, this result implies the need to clarify the present-day geographic distribution of each of these fox species, while it may also indicate an ongoing hybridization process between them. Future testing of this hypothesis with in-depth analyses of these populations is thus a priority for understanding the history, evolutionary dynamics and present-day composition of this endemic Neotropical genus.
Induced Seismicity at the UK "Hot Dry Rock" Test Site for Geothermal Energy Production
NASA Astrophysics Data System (ADS)
Li, Xun; Main, Ian; Jupe, Andrew
2018-03-01
In enhanced geothermal systems (EGS), fluid is injected at high pressure in order to stimulate fracturing and/or fluid flow through otherwise relatively impermeable underlying hot rocks to generate power and/or heat. The stimulation induces micro-earthquakes whose precise triggering mechanism and relationship to new and pre-existing fracture networks are still the subject of some debate. Here we analyse the dataset for induced micro-earthquakes at the UK "hot dry rock" experimental geothermal site (Rosemanowes, Cornwall). We quantify the evolution of several metrics used to characterise induced seismicity, including the seismic strain partition factor and the "seismogenic index". The results show a low strain partition factor of 0.01% and a low seismogenenic index indicating that aseismic processes dominate. We also analyse the spatio-temporal distribution of hypocentres, using simple models for the evolution of hydraulic diffusivity by (a) isotropic and (b) anisotropic pore-pressure relaxation. The principal axes of the diffusivity or permeability tensor inferred from the spatial distribution of earthquake foci are aligned parallel to the present-day stress field, although the maximum permeability is vertical, whereas the maximum principal stress is horizontal. Our results are consistent with a triggering mechanism that involves (a) seismic shear slip along optimally-oriented pre-existing fractures, (b) a large component of aseismic slip with creep (c) activation of tensile fractures as hydraulic conduits created by both the present-day stress field and by the induced shear slip, both exploiting pre-existing joint sets exposed in borehole data.
Distribution Route Planning of Clean Coal Based on Nearest Insertion Method
NASA Astrophysics Data System (ADS)
Wang, Yunrui
2018-01-01
Clean coal technology has made some achievements for several ten years, but the research in its distribution field is very small, the distribution efficiency would directly affect the comprehensive development of clean coal technology, it is the key to improve the efficiency of distribution by planning distribution route rationally. The object of this paper was a clean coal distribution system which be built in a county. Through the surveying of the customer demand and distribution route, distribution vehicle in previous years, it was found that the vehicle deployment was only distributed by experiences, and the number of vehicles which used each day changed, this resulted a waste of transport process and an increase in energy consumption. Thus, the mathematical model was established here in order to aim at shortest path as objective function, and the distribution route was re-planned by using nearest-insertion method which been improved. The results showed that the transportation distance saved 37 km and the number of vehicles used had also been decreased from the past average of 5 to fixed 4 every day, as well the real loading of vehicles increased by 16.25% while the current distribution volume staying same. It realized the efficient distribution of clean coal, achieved the purpose of saving energy and reducing consumption.
Flow-duration-frequency behaviour of British rivers based on annual minima data
NASA Astrophysics Data System (ADS)
Zaidman, Maxine D.; Keller, Virginie; Young, Andrew R.; Cadman, Daniel
2003-06-01
A comparison of different probability distribution models for describing the flow-duration-frequency behaviour of annual minima flow events in British rivers is reported. Twenty-five catchments were included in the study, each having stable and natural flow records of at least 30 years in length. Time series of annual minima D-day average flows were derived for each record using durations ( D) of 1, 7, 30, 60, 90, and 365 days and used to construct low flow frequency curves. In each case the Gringorten plotting position formula was used to determine probabilities (of non-exceedance). Four distribution types—Generalised Extreme Value (GEV), Generalised Logistic (GL), Pearson Type-3 (PE3) and Generalised Pareto (GP)—were used to model the probability distribution function for each site. L-moments were used to parameterise individual models, whilst goodness-of-fit tests were used to assess their match to the sample data. The study showed that where short durations (i.e. 60 days or less) were considered, high storage catchments tended to be best represented by GL and GEV distribution models whilst low storage catchments were best described by PE3 or GEV models. However, these models produced reasonable results only within a limited range (e.g. models for high storage catchments did not produce sensible estimates of return periods where the prescribed flow was less than 10% of the mean flow). For annual minima series derived using long duration flow averages (e.g. more than 90 days), GP and GEV models were generally more applicable. The study suggests that longer duration minima do not conform to the same distribution types as short durations, and that catchment properties can influence the type of distribution selected.
RBC Distribution Width: Biomarker for Red Cell Dysfunction and Critical Illness Outcome?
Said, Ahmed S; Spinella, Philip C; Hartman, Mary E; Steffen, Katherine M; Jackups, Ronald; Holubkov, Richard; Wallendorf, Mike; Doctor, Allan
2017-02-01
RBC distribution width is reported to be an independent predictor of outcome in adults with a variety of conditions. We sought to determine if RBC distribution width is associated with morbidity or mortality in critically ill children. Retrospective observational study. Tertiary PICU. All admissions to St. Louis Children's Hospital PICU between January 1, 2005, and December 31, 2012. We collected demographics, laboratory values, hospitalization characteristics, and outcomes. We calculated the relative change in RBC distribution width from admission RBC distribution width to the highest RBC distribution width during the first 7 days of hospitalization. Our primary outcome was ICU mortality or use of extracorporeal membrane oxygenation as a composite. Secondary outcomes were ICU- and ventilator-free days. We identified 3,913 eligible subjects with an estimated mortality (by Pediatric Index of Mortality 2) of 2.94% ± 9.25% and an actual ICU mortality of 2.91%. For the study cohort, admission RBC distribution width was 14.12% ± 1.89% and relative change in RBC distribution width was 2.63% ± 6.23%. On univariate analysis, both admission RBC distribution width and relative change in RBC distribution width correlated with mortality or the use of extracorporeal membrane oxygenation (odds ratio, 1.19 [95% CI, 1.12-1.27] and odds ratio, 1.06 [95% CI, 1.04-1.08], respectively; p < 0.001). After adjusting for confounding variables, including severity of illness, both admission RBC distribution width (odds ratio, 1.13; 95% CI, 1.03-1.24) and relative change in RBC distribution width (odds ratio, 1.04; 95% CI, 1.01-1.07) remained independently associated with ICU mortality or the use of extracorporeal membrane oxygenation. Admission RBC distribution width and relative change in RBC distribution width both weakly correlated with fewer ICU- (r = 0.038) and ventilator-free days (r = 0.05) (p < 0.001). Independent of illness severity in critically ill children, admission RBC distribution width is associated with ICU mortality and morbidity. These data suggest that RBC distribution width may be a biomarker for RBC injury that is of sufficient magnitude to influence critical illness outcome, possibly via oxygen delivery impairment.
Nishiura, Hiroshi
2009-01-01
Determination of the most appropriate quarantine period for those exposed to smallpox is crucial to the construction of an effective preparedness program against a potential bioterrorist attack. This study reanalyzed data on the incubation period distribution of smallpox to allow the optimal quarantine period to be objectively calculated. In total, 131 cases of smallpox were examined; incubation periods were extracted from four different sets of historical data and only cases arising from exposure for a single day were considered. The mean (median and standard deviation (SD)) incubation period was 12.5 (12.0, 2.2) days. Assuming lognormal and gamma distributions for the incubation period, maximum likelihood estimates (and corresponding 95% confidence interval (CI)) of the 95th percentile were 16.4 (95% CI: 15.6, 17.9) and 16.2 (95% CI: 15.5, 17.4) days, respectively. Using a non-parametric method, the 95th percentile point was estimated as 16 (95% CI: 15, 17) days. The upper 95% CIs of the incubation periods at the 90th, 95th and 99th percentiles were shorter than 17, 18 and 23 days, respectively, using both parametric and non-parametric methods. These results suggest that quarantine measures can ensure non-infection among those exposed to smallpox with probabilities higher than 95-99%, if the exposed individuals are quarantined for 18-23 days after the date of contact tracing.
Maier, Kristina; Olias, Philipp; Enderlein, Dirk; Klopfleisch, Robert; Mayr, Sylvia L; Gruber, Achim D; Lierz, Michael
2015-01-01
Pigeon protozoal encephalitis is a biphasic, neurologic disease of domestic pigeons (Columba livia f. domestica) caused by the apicomplexan parasite Sarcocystis calchasi. Despite severe inflammatory lesions of the brain, associated parasitic stages have only rarely been identified and the cause of the lesions is still unclear. The aim of this study was therefore to characterize the tissue distribution of S. calchasi within pigeons between the two clinical phases and during the occurrence of neurological signs. For this purpose, a semi-quantitative real-time polymerase chain reaction (PCR) was developed. Forty-five domestic pigeons were infected orally (via a cannula into the crop) with 200 S. calchasi sporocysts and euthanized in groups of three pigeons at intervals of 2 to 10 days over a period of 61 days. Tissue samples including brain and skeletal muscle were examined by histology, immunohistochemistry, and PCR. Schizonts were detected in the liver of one pigeon at day 10 post infection. A mild encephalitis was detected at day 20 post infection, around 4 weeks before the onset of neurological signs. At the same time, immature sarcocysts were present in the skeletal muscle. In seven pigeons a few sarcocysts were identified in the brain, but not associated with any lesion. These results suggest that the encephalitis is induced at a very early stage of the S. calchasi lifecycle rather than in the chronic phase of pigeon protozoal encephalitis. Despite the increasing severity of lesions in the central nervous system, the amount of sarcocysts did not increase. This supports the hypothesis of a delayed-type hypersensitivity response as the cause of the encephalitis. The study also demonstrated that S. calchasi DNA is detectable in tissues negative by histological methods, indicating a higher sensitivity of the real-time PCR.
Sympatry influence in the interaction of Trypanosoma cruzi with triatomine.
Dworak, Elaine Schultz; Araújo, Silvana Marques de; Gomes, Mônica Lúcia; Massago, Miyoko; Ferreira, Érika Cristina; Toledo, Max Jean de Ornelas
2017-01-01
Trypanosoma cruzi, the etiologic agent of Chagas disease, is widely distributed in nature, circulating between triatomine bugs and sylvatic mammals, and has large genetic diversity. Both the vector species and the genetic lineages of T. cruzi present a varied geographical distribution. This study aimed to verify the influence of sympatry in the interaction of T. cruzi with triatomines. Methods: The behavior of the strains PR2256 (T. cruzi II) and AM14 (T. cruzi IV) was studied in Triatoma sordida (TS) and Rhodnius robustus (RR). Eleven fifth-stage nymphs were fed by artificial xenodiagnosis with 5.6 × 103 blood trypomastigotes/0.1mL of each T. cruzi strain. Every 20 days, their excreta were examined for up to 100 days, and every 30 days, the intestinal content was examined for up to 120 days, by parasitological (fresh examination and differential count with Giemsa-stained smears) and molecular (PCR) methods. Rates of infectivity, metacyclogenesis and mortality, and mean number of parasites per insect and of excreted parasites were determined. Sympatric groups RR+AM14 and TS+PR2256 showed higher values of the four parameters, except for mortality rate, which was higher (27.3%) in the TS+AM14 group. General infectivity was 72.7%, which was mainly proven by PCR, showing the following decreasing order: RR+AM14 (100%), TS+PR2256 (81.8%), RR+PR2256 (72.7%) and TS+AM14 (36.4%). Our working hypothesis was confirmed once higher infectivity and vector capacity (flagellate production and elimination of infective metacyclic forms) were recorded in the groups that contained sympatric T. cruzi lineages and triatomine species.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vuillemenot, Brian R., E-mail: bvuillemenot@bmrn.com; Kennedy, Derek; Reed, Randall P.
CLN2 disease is caused by deficiency in tripeptidyl peptidase-1 (TPP1), leading to neurodegeneration and death. The safety, pharmacokinetics (PK), and CNS distribution of recombinant human TPP1 (rhTPP1) were characterized following a single intracerebroventricular (ICV) or intrathecal-lumbar (IT-L) infusion to cynomolgus monkeys. Animals received 0, 5, 14, or 20 mg rhTPP1, ICV, or 14 mg IT-L, in artificial cerebrospinal fluid (aCSF) vehicle. Plasma and CSF were collected for PK analysis. Necropsies occurred at 3, 7, and 14 days post-infusion. CNS tissues were sampled for rhTPP1 distribution. TPP1 infusion was well tolerated and without effect on clinical observations or ECG. A mildmore » increase in CSF white blood cells (WBCs) was detected transiently after ICV infusion. Isolated histological changes related to catheter placement and infusion were observed in ICV treated animals, including vehicle controls. The CSF and plasma exposure profiles were equivalent between animals that received an ICV or IT-L infusion. TPP1 levels peaked at the end of infusion, at which point the enzyme was present in plasma at 0.3% to 0.5% of CSF levels. TPP1 was detected in brain tissues with half-lives of 3–14 days. CNS distribution between ICV and IT-L administration was similar, although ICV resulted in distribution to deep brain structures including the thalamus, midbrain, and striatum. Direct CNS infusion of rhTPP1 was well tolerated with no drug related safety findings. The favorable nonclinical profile of ICV rhTPP1 supports the treatment of CLN2 by direct administration to the CNS. - Highlights: • TPP1 enzyme replacement therapy to the CNS is in development for CLN2 disease. • Toxicology, pharmacokinetics, and CNS distribution were assessed in monkeys. • TPP1 infusion directly to the brain did not result in any safety concerns. • A positive pharmacokinetic and distribution profile resulted from TPP1 infusion. • This study demonstrates the feasibility of ICV administered rhTPP1 to treat CLN2.« less
Stewart, Jana S.; Covert, S. Alex; Estes, Nick J.; Westenbroek, Stephen M.; Krueger, Damon; Wieferich, Daniel J.; Slattery, Michael T.; Lyons, John D.; McKenna, James E.; Infante, Dana M.; Bruce, Jennifer L.
2016-10-13
Climate change is expected to alter the distributions and community composition of stream fishes in the Great Lakes region in the 21st century, in part as a result of altered hydrological systems (stream temperature, streamflow, and habitat). Resource managers need information and tools to understand where fish species and stream habitats are expected to change under future conditions. Fish sample collections and environmental variables from multiple sources across the United States Great Lakes Basin were integrated and used to develop empirical models to predict fish species occurrence under present-day climate conditions. Random Forests models were used to predict the probability of occurrence of 13 lotic fish species within each stream reach in the study area. Downscaled climate data from general circulation models were integrated with the fish species occurrence models to project fish species occurrence under future climate conditions. The 13 fish species represented three ecological guilds associated with water temperature (cold, cool, and warm), and the species were distributed in streams across the Great Lakes region. Vulnerability (loss of species) and opportunity (gain of species) scores were calculated for all stream reaches by evaluating changes in fish species occurrence from present-day to future climate conditions. The 13 fish species included 4 cold-water species, 5 cool-water species, and 4 warm-water species. Presently, the 4 cold-water species occupy from 15 percent (55,000 kilometers [km]) to 35 percent (130,000 km) of the total stream length (369,215 km) across the study area; the 5 cool-water species, from 9 percent (33,000 km) to 58 percent (215,000 km); and the 4 warm-water species, from 9 percent (33,000 km) to 38 percent (141,000 km).Fish models linked to projections from 13 downscaled climate models projected that in the mid to late 21st century (2046–65 and 2081–2100, respectively) habitats suitable for all 4 cold-water species and 4 of 5 cool-water species under present-day conditions will decline as much as 86 percent and as little as 33 percent, and habitats suitable for all 4 warm-water species will increase as much as 33 percent and as little as 7 percent. This report documents the approach and data used to predict and project fish species occurrence under present-day and future climate conditions for 13 lotic fish species in the United States Great Lakes Basin. A Web-based decision support mapping application termed “FishVis” was developed to provide a means to integrate, visualize, query, and download the results of these projected climate-driven responses and help inform conservation planning efforts within the region.
Maintenance-free operation of WDM quantum key distribution system through a field fiber over 30 days
NASA Astrophysics Data System (ADS)
Yoshino, Ken-ichiro; Ochi, Takao; Fujiwara, Mikio; Sasaki, Masahide; Tajima, Akio
2013-12-01
Maintenance-free wavelength-division-multiplexing quantum key distribution for 30 days was achieved through a 22-km field fiber. Using polarization-independent interferometers and stabilization techniques, we attained a quantum bit error rate as low as 1.70% and a key rate as high as 229.8 kbps, making the record of total secure key of 595.6 Gbits accumulated over an uninterrupted operation period.
Cryptographic robustness of practical quantum cryptography: BB84 key distribution protocol
DOE Office of Scientific and Technical Information (OSTI.GOV)
Molotkov, S. N.
2008-07-15
In real fiber-optic quantum cryptography systems, the avalanche photodiodes are not perfect, the source of quantum states is not a single-photon one, and the communication channel is lossy. For these reasons, key distribution is impossible under certain conditions for the system parameters. A simple analysis is performed to find relations between the parameters of real cryptography systems and the length of the quantum channel that guarantee secure quantum key distribution when the eavesdropper's capabilities are limited only by fundamental laws of quantum mechanics while the devices employed by the legitimate users are based on current technologies. Critical values are determinedmore » for the rate of secure real-time key generation that can be reached under the current technology level. Calculations show that the upper bound on channel length can be as high as 300 km for imperfect photodetectors (avalanche photodiodes) with present-day quantum efficiency ({eta} {approx} 20%) and dark count probability (p{sub dark} {approx} 10{sup -7})« less
Hampton, M.A.; Bouma, A.H.; Frost, T.P.; Colburn, I.P.
1979-01-01
Surficial sediments of the Kodiak shelf, Gulf of Alaska, contain various amounts of volcanic ash whose physical properties indicate that it originated from the 1912 Katmai eruption. The distribution of ash is related to the shelf physiography and represents redistribution by oceanic circulation rather than the original depositional pattern from the volcanic event. The ash distribution can be used, in conjunction with the distribution of grain sizes, as an indicator of present-day sediment dispersal patterns on the shelf. No significant modern input of sediment is occurring on the Kodiak shelf, which is mostly covered by Pleistocene glacial deposits. Coarse-grained sediments on flat portions of shallow banks apparently are being winnowed, with the removed ash-rich fine material being deposited in shallow depressions on the banks and in three of the four major troughs that cut transversely across the shelf. The other major trough seems to be experiencing a relatively high-energy current regime, with little deposition of fine material. ?? 1979.
Cryptographic robustness of practical quantum cryptography: BB84 key distribution protocol
NASA Astrophysics Data System (ADS)
Molotkov, S. N.
2008-07-01
In real fiber-optic quantum cryptography systems, the avalanche photodiodes are not perfect, the source of quantum states is not a single-photon one, and the communication channel is lossy. For these reasons, key distribution is impossible under certain conditions for the system parameters. A simple analysis is performed to find relations between the parameters of real cryptography systems and the length of the quantum channel that guarantee secure quantum key distribution when the eavesdropper’s capabilities are limited only by fundamental laws of quantum mechanics while the devices employed by the legitimate users are based on current technologies. Critical values are determined for the rate of secure real-time key generation that can be reached under the current technology level. Calculations show that the upper bound on channel length can be as high as 300 km for imperfect photodetectors (avalanche photodiodes) with present-day quantum efficiency (η ≈ 20%) and dark count probability ( p dark ˜ 10-7).
NASA Astrophysics Data System (ADS)
Amere, Y. B.; Bendick, R. O.; Fisseha, S.; Lewi, E.; Reilinger, R. E.; King, R. W.; Kianji, G.
2014-12-01
27 campaign and 17 continuous GPS sites spanning the Ethiopian Highlands, Main Ethiopian Rift (MER), and Somali Platform in Ethiopia and Eritrea were measured for varying durations between 1995 and 2014. Velocities at these sites show that present day strain in NE Africa is not localized only in the Afar depression and MER system. Rather, velocities as high as 6 mm/yr relative to stable Nubia occur in the central Ethiopian highlands west of the rift bounding faults; the northern and southern Ethiopian highlands host velocities as high as 3 mm/yr. These approach the magnitude of Nubia-Somalia spreading accommodated within the rift itself of 6 + 1 mm/yr with an azimuth of N770E. The combination of distributed low strain rate deformation contiguous with higher strain rate plate boundary deformation is similar to that expressed in other tectonically active continental settings like Basin and Range and Tibetan Plateau.Keywords: deformation, localized, distributed, strain, stable Nubia.
Political complexity predicts the spread of ethnolinguistic groups
Currie, Thomas E.; Mace, Ruth
2009-01-01
Human languages show a remarkable degree of variation in the area they cover. However, the factors governing the distribution of human cultural groups such as languages are not well understood. While previous studies have examined the role of a number of environmental variables the importance of cultural factors has not been systematically addressed. Here we use a geographical information system (GIS) to integrate information about languages with environmental, ecological, and ethnographic data to test a number of hypotheses that have been proposed to explain the global distribution of languages. We show that the degree of political complexity and type of subsistence strategy exhibited by societies are important predictors of the area covered by a language. Political complexity is also strongly associated with the latitudinal gradient in language area, whereas subsistence strategy is not. We argue that a process of cultural group selection favoring more complex societies may have been important in shaping the present-day global distribution of language diversity. PMID:19380740
Mechanistic species distribution modelling as a link between physiology and conservation.
Evans, Tyler G; Diamond, Sarah E; Kelly, Morgan W
2015-01-01
Climate change conservation planning relies heavily on correlative species distribution models that estimate future areas of occupancy based on environmental conditions encountered in present-day ranges. The approach benefits from rapid assessment of vulnerability over a large number of organisms, but can have poor predictive power when transposed to novel environments and reveals little in the way of causal mechanisms that define changes in species distribution or abundance. Having conservation planning rely largely on this single approach also increases the risk of policy failure. Mechanistic models that are parameterized with physiological information are expected to be more robust when extrapolating distributions to future environmental conditions and can identify physiological processes that set range boundaries. Implementation of mechanistic species distribution models requires knowledge of how environmental change influences physiological performance, and because this information is currently restricted to a comparatively small number of well-studied organisms, use of mechanistic modelling in the context of climate change conservation is limited. In this review, we propose that the need to develop mechanistic models that incorporate physiological data presents an opportunity for physiologists to contribute more directly to climate change conservation and advance the field of conservation physiology. We begin by describing the prevalence of species distribution modelling in climate change conservation, highlighting the benefits and drawbacks of both mechanistic and correlative approaches. Next, we emphasize the need to expand mechanistic models and discuss potential metrics of physiological performance suitable for integration into mechanistic models. We conclude by summarizing other factors, such as the need to consider demography, limiting broader application of mechanistic models in climate change conservation. Ideally, modellers, physiologists and conservation practitioners would work collaboratively to build models, interpret results and consider conservation management options, and articulating this need here may help to stimulate collaboration.
Proceedings of RIKEN BNL Research Center Workshop: Progress in High-pT Physics at RHIC
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bazilevsky, A.; Bland, L.; Vogelsang, W.
2010-03-17
This volume archives the presentations at the RIKEN BNL Research Center workshop 'Progress in High-PT Physics at RHIC', held at BNL in March 2010. Much has been learned from high-p{sub T} physics after 10 years of RHIC operations for heavy-ion collisions, polarized proton collisions and d+Au collisions. The workshop focused on recent progress in these areas by both theory and experiment. The first morning saw review talks on the theory of RHIC high-p{sub T} physics by G. Sterman and J. Soffer, and on the experimental results by M. Tannenbaum. One of the most exciting recent results from the RHIC spinmore » program is the first observation of W bosons and their associated single-spin asymmetry. The new preliminary data were reported on the first day of our workshop, along with a theoretical perspective. There also were detailed discussions on the global analysis of polarized parton distributions, including the knowledge on gluon polarization and the impact of the W-data. The main topic of the second workshop day were single-transverse spin asymmetries and their analysis in terms of transverse-momentum dependent parton distributions. There is currently much interest in a future Drell-Yan program at RHIC, thanks to the exciting physics opportunities this would offer. This was addressed in some of the talks. There also were presentations on the latest results on transverse-spin physics from HERMES and BELLE. On the final day of the workshop, the focus shifted toward forward and small-x physics at RHIC, which has become a cornerstone of the whole RHIC program. Exciting new data were presented and discussed in terms of their possible implications for our understanding of strong color-field phenomena in QCD. In the afternoon, there were discussions of nuclear parton distributions and jet observables, among them fragmentation. The workshop was concluded with outlooks toward the near-term (LHC, JLab) and longer-term (EIC) future. The workshop has been a great success. We had excellent presentations throughout and productive discussions, which showed the importance and unique value of the RHIC high-p{sub T} program. We are grateful to all participants for coming to BNL. The support provided by the RIKEN-BNL Research Center for this workshop has been magnificent, and we are most grateful for it. We also thank Brookhaven National Laboratory and the U.S. Department of Energy for providing additional support and for the facilities to hold this workshop. Finally, sincere thanks go to Pamela Esposito for her most efficient and tireless work in organizing and running the workshop.« less
Castellari, Elena; Cotti, Chad; Gordanier, John; Ozturk, Orgul
2017-11-01
In this paper, we examine the relationship between the timing of food stamp receipt and purchasing patterns. We combine data on state distribution dates of food stamps with scanner data on a panel of households purchases tracked between 2004 and 2011. We find that purchases of a variety of goods are meaningfully higher on receipt days, consistent with previous work that suggests that recipients are very impatient. Additionally, and importantly, estimates indicate that when food stamp receipt days fall on weekends, total monthly purchases within the same households are affected. In particular, monthly purchases of beer are higher when food stamps are distributed on a weekend rather than in months where benefits are distributed on weekdays. For these households, total beer purchases are between 4 and 5% higher in those months. Among households ineligible for food stamps, no effect is identified. These results demonstrate that the 'day-of-the-week' of SNAP treatment may have important impacts on household purchase habits. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.
NASA Astrophysics Data System (ADS)
Ojo, Joseph Sunday
2017-05-01
The study of the influence of cloud cover on satellite propagation links is becoming more demanding due to the requirement of larger bandwidth for different satellite applications. Cloud attenuation is one of the major factors to consider for optimum performance of Ka/V and other higher frequency bands. In this paper, the geo-spatial distribution of cloud coverage over some chosen stations in Nigeria has been considered. The substantial scale spatial dispersion of cloud cover based on synoptic meteorological data and the possible impact on satellite communication links at higher frequency bands was also investigated. The investigation was based on 5 years (2008-2012) achieved cloud cover data collected by the Nigerian Meteorological Agency (NIMET) Federal Ministry of Aviation, Oshodi Lagos over four synoptic hours of the day covering day and night. The performances of satellite signals as they traverse through the cloud and cloud noise temperature at different seasons and over different hours of days at Ku/W-bands frequency are also examined. The overall result shows that the additional total atmospheric noise temperature due to the clear air effect and the noise temperature from the cloud reduces the signal-to-noise ratio of the satellite receiver systems, leading to more signal loss and if not adequately taken care of may lead to significant outage. The present results will be useful for Earth-space link budgeting, especially for the proposed multi-sensors communication satellite systems in Nigeria.
Meals, snacks and food choices in Brazilian shift workers with high energy expenditure.
de Assis, M A A; Nahas, M V; Bellisle, F; Kupek, E
2003-08-01
To describe the food intake of garbage collectors, who works in three shifts, in terms of meal and snack frequency, content, time distribution and the contribution of various popular foods to the total diet. Sixty-six Brazilian garbage collectors, who work in morning, afternoon, and night shift, participated in the present study. The quantitative methods used were a combination of one 24-h recall and two 24-h records during three nonconsecutive work days. The qualitative method used was the food-based classification of eating episodes model modified in order to define meals or snacks in three categories of events: meals with three food groups of high nutrient density (three HND meals), meals with two food groups of high nutrient density (two HND meals) and snacks, composed of only one food category of high nutrient density. The total number of eating events per day was significantly higher for night shift workers. Over 24-h, 'two HND meals' were the most common events and contributed the most energy, in all three shifts. Night shift workers ate more at dawn and less in the morning than other shifts. In all three shifts, meat was the most important food contributing to energy intake. Different work schedules did not affect the relative frequency of meal types and snacks or their contribution to daily energy intake, but affected the daily distribution of eating events, with a redistribution of intake from day to night in night shift workers.
Huang, Wen; Yang, Jiyu; Li, Candong; Wen, Zixiang; Li, Yinghui; Guan, Rongxia; Guo, Yong; Chang, Ruzhen; Wang, Dechun; Wang, Shuming; Qiu, Li-Juan
2016-01-01
The growth period traits are important traits that affect soybean yield. The insights into the genetic basis of growth period traits can provide theoretical basis for cultivated area division, rational distribution, and molecular breeding for soybean varieties. In this study, genome-wide association analysis (GWAS) was exploited to detect the quantitative trait loci (QTL) for number of days to flowering (ETF), number of days from flowering to maturity (FTM), and number of days to maturity (ETM) using 4032 single nucleotide polymorphism (SNP) markers with 146 cultivars mainly from Northeast China. Results showed that abundant phenotypic variation was presented in the population, and variation explained by genotype, environment, and genotype by environment interaction were all significant for each trait. The whole accessions could be clearly clustered into two subpopulations based on their genetic relatedness, and accessions in the same group were almost from the same province. GWAS based on the unified mixed model identified 19 significant SNPs distributed on 11 soybean chromosomes, 12 of which can be consistently detected in both planting densities, and 5 of which were pleotropic QTL. Of 19 SNPs, 7 SNPs located in or close to the previously reported QTL or genes controlling growth period traits. The QTL identified with high resolution in this study will enrich our genomic understanding of growth period traits and could then be explored as genetic markers to be used in genomic applications in soybean breeding. PMID:27367048
NASA Astrophysics Data System (ADS)
Chapman, Sandra; Stainforth, David; Watkins, Nick
2014-05-01
Estimates of how our climate is changing are needed locally in order to inform adaptation planning decisions. This requires quantifying the geographical patterns in changes at specific quantiles in distributions of variables such as daily temperature or precipitation. Here we focus on these local changes and on a method to transform daily observations of precipitation into patterns of local climate change. We develop a method[1] for analysing local climatic timeseries to assess which quantiles of the local climatic distribution show the greatest and most robust changes, to specifically address the challenges presented by daily precipitation data. We extract from the data quantities that characterize the changes in time of the likelihood of daily precipitation above a threshold and of the relative amount of precipitation in those days. Our method is a simple mathematical deconstruction of how the difference between two observations from two different time periods can be assigned to the combination of natural statistical variability and/or the consequences of secular climate change. This deconstruction facilitates an assessment of how fast different quantiles of precipitation distributions are changing. This involves both determining which quantiles and geographical locations show the greatest change but also, those at which any change is highly uncertain. We demonstrate this approach using E-OBS gridded data[2] timeseries of local daily precipitation from specific locations across Europe over the last 60 years. We treat geographical location and precipitation as independent variables and thus obtain as outputs the pattern of change at a given threshold of precipitation and with geographical location. This is model- independent, thus providing data of direct value in model calibration and assessment. Our results show regionally consistent patterns of systematic increase in precipitation on the wettest days, and of drying across all days which is of potential value in adaptation planning. [1] S C Chapman, D A Stainforth, N W Watkins, 2013, On Estimating Local Long Term Climate Trends, Phil. Trans. R. Soc. A, 371 20120287; D. A. Stainforth, 2013, S. C. Chapman, N. W. Watkins, Mapping climate change in European temperature distributions, Environ. Res. Lett. 8, 034031 [2] Haylock, M.R., N. Hofstra, A.M.G. Klein Tank, E.J. Klok, P.D. Jones and M. New. 2008: A European daily high-resolution gridded dataset of surface temperature and precipitation. J. Geophys. Res (Atmospheres), 113, D20119
NASA Astrophysics Data System (ADS)
Engelstaedter, S.; Washington, R.; Allen, C.; Flamant, C.; Chaboureau, J.-P.; Kocha, C.; Lavaysse, C.
2012-04-01
The near-surface low pressure system that develops over western Africa in Boreal summer (know as the Saharan Heat Low) is thought to have a significant influence on regional and global climate due to its links with the Monsoon, the Northern Atlantic and the Mediterranean climate system. The SHL is associated with the deepest atmospheric boundary layer on the planet and is co-located with the highest dust loadings in the world. The processes that link the heat low and dust distribution are only poorly understood. Improving the representation of the heat low and the processes that control the emission and atmospheric distribution of dust in climate and NWP models is crucial if we are to reduce known systematic errors in climate predictions and weather forecasts. In collaboration with European partners, the UK-based consortium project "Fennec - The Saharan Climate System" aims at improving our understanding of this complex climate system by integrating for the first time coordinated ground and aircraft observations from the central Sahara, newly developed satellite products, and the application of regional and global models. On 22 June 2011, two research aircraft operating out of Fuerteventura (Spain) surveyed the Saharan Heat Low centred over Mauritania-Mali border. The aircraft flew simultaneously in the morning and in the afternoon on two different tracks thereby sampling each track four times on that day. Both aircraft were equipped with a downward looking LIDAR for aerosol detection. In total, 51 sondes were dropped during the flights making this the most comprehensive dataset to study the spatio-temporal diurnal evolution of the heat low including the interactions between the atmospheric boundary layer and dust distributions. Combining LIDAR observations, satellite imagery and back-trajectory modelling we show that an aged dust layer was present in the heat low region resulting from previous day's dust activity associated with a south-moving density current from the Atlas mountains and westward-moving Haboob fronts originating along the Algeria-Mali border. We show how the dust is distributed within the atmosphere and how it is modified during the course of the day by various processes including the development of the atmospheric boundary layer and associated dry convection as well as the inflow of moisture-rich monsoon air from the south.
Bursts of Self-Conscious Emotions in the Daily Lives of Emerging Adults.
Conroy, David E; Ram, Nilam; Pincus, Aaron L; Rebar, Amanda L
Self-conscious emotions play a role in regulating daily achievement strivings, social behavior, and health, but little is known about the processes underlying their daily manifestation. Emerging adults (n = 182) completed daily diaries for eight days and multilevel models were estimated to evaluate whether, how much, and why their emotions varied from day-to-day. Within-person variation in authentic pride was normally-distributed across people and days whereas the other emotions were burst-like and characterized by zero-inflated, negative binomial distributions. Perceiving social interactions as generally communal increased the odds of hubristic pride activation and reduced the odds of guilt activation; daily communal behavior reduced guilt intensity. Results illuminated processes through which meaning about the self-in-relation-to-others is constructed during a critical period of development.
Characterization of symptoms and edema distribution in premenstrual syndrome
Tacani, Pascale Mutti; Ribeiro, Danielle de Oliveira; Barros Guimarães, Barbara Evelyn; Machado, Aline Fernanda Perez; Tacani, Rogério Eduardo
2015-01-01
Background Premenstrual syndrome is a group of symptoms linked to the menstrual cycle, and edema is among these symptoms. Physiotherapy is often sought by many patients for the treatment of edema; however, for an adequate prescription of physiotherapeutic procedures, the distribution of edema throughout the body has yet to be characterized. Objective To determine the most frequent symptoms and body regions that present with edema in women during the premenstrual period. Subjects and methods Sixty women with a mean age of 24.6±4.7 years were evaluated during their premenstrual (between days 21 and 28) and menstrual period (between days 1 and 3), and the collected data included body mass, height, biotype (body-fat distribution), face, breast, limb-circumference measurements, and limb-volume estimate, and an adapted version of the Premenstrual Symptoms Screening Tool was used. Statistical analysis was performed using Student’s t-test and the test for equality of two proportions (P≤0.05). Results Premenstrual syndrome was identified in 91.7% of the women, and the most frequent symptoms were irritability (73.33%) and physical symptoms, including swelling (65%), and anxiety (58.3%). Edema was detected in the following areas: facial, epigastric, mammary, umbilical, and pubic, the mid-third of the arms, distal forearm, in both thighs and in the mid-third of the legs determined by circumference measurements, and in both upper and lower limbs, according to the estimated volume. Conclusion In this study population, the most frequent symptoms were irritability, physical symptoms, and anxiety, with distribution of edema in the face, breast, abdomen, pubic area, distal upper limb, and proximal lower limb. PMID:25792857
Haugan, T; Gaustad, A H; Reksen, O; Gröhn, Y T; Hofmo, P O
2007-02-01
The objective of the present field study was to compare the fertility results for boar semen diluted in X-cell stored up to 4-5 days before artificial insemination (AI) with semen diluted in Beltsville thawing solution (BTS) used for AI following 2-3 days of storage (where the first day being the collection day). A total number of 2601 double inseminations in Norwegian herds were included in this two-trial study. All the boars used in the study were mature cross-bred Norwegian Landrace x Duroc (LD), which were routinely used for AI in Norway. The inseminated gilts and sows were Norwegian Landrace x Yorkshire (LY). The AI doses contained 2.5 billion spermatozoa, and consisted of a mixture of semen from three, occasionally four, boars (i.e. heterospermic semen). Fertility was measured in terms of the likelihood of farrowing and subsequent litter size. The fertility of the semen in both of the extenders was satisfactory and no significant differences were found either in semen stored 4-5 days in X-cell compared with 2-3 days in BTS or in semen stored 2-3 days in X-cell compared with 2-3 days in BTS. The storage capability findings for the long-term extender X-cell could significantly simplify the practical issues of semen production and the distribution of AI doses containing 2.5 billion spermatozoa. However, in pig production systems where all semen is used within 2-3 days, the short-term extender BTS is as good as the more expensive extender X-cell.
de Jonge, Mario; Tabbers, Huib K; Pecher, Diane; Zeelenberg, René
2012-03-01
In 2 experiments, we investigated the effect of presentation rate on both immediate (5 min) and delayed (2 days) cued recall of paired associates. Word pairs were presented for a total of 16 s per pair, with presentation duration of individual presentations varying from 1 to 16 s. In Experiment 1, participants studied word pairs with presentation rates of 16 × 1 s, 8 × 2 s, 4 × 4 s, 2 × 8 s, or 1 × 16 s. A nonmonotonic relationship was found between presentation rate and cued recall performance. Both short (e.g., 1 s) and long (e.g., 16 s) presentation durations resulted in poor immediate and delayed recall, compared with intermediate presentation durations. In Experiment 2, we replicated these general findings. Moreover, we showed that the 4 s condition resulted in less proportional forgetting than the 1 s and the 16 s conditions. 2012 APA, all rights reserved
Chemical OSSEs in Global Modeling and Assimilation Office (GMAO)
NASA Technical Reports Server (NTRS)
Pawson, Steven
2008-01-01
This presentation will summarize ongoing 'chemical observing system simulation experiment (OSSE)' work in the Global Modeling and Assimilation Office (GMAO). Weather OSSEs are being studied in detail, with a 'nature run' based on the European Centre for Medium-Range Weather Forecasts (ECMWF) model that can be sampled by a synthesized suite of satellites that reproduces present-day observations. Chemical OSSEs are based largely on the carbon-cycle project and aim to study (1) how well we can reproduce the observed carbon distribution with the Atmospheric Infrared Sounder (AIRS) and Orbiting Carbon Observatory (OCO) sensors and (2) with what accuracy can we deduce surface sources and sinks of carbon species in an assimilation system.
NASA Astrophysics Data System (ADS)
Powell, Eric N.; Kuykendall, Kelsey M.; Moreno, Paula
2017-06-01
A comprehensive dataset for the Georges Bank region is used to directly compare the distribution of the death assemblage and the living community at large spatial scales and to assess the application of the death assemblage in tracking changes in species' distributional pattern as a consequence of climate change. Focus is placed on the biomass-dominant clam species of the northwest Atlantic continental shelf: the surfclam Spisula solidissima and the ocean quahog Arctica islandica, for which extensive datasets exist on the distributions of the living population and the death assemblage. For both surfclams and ocean quahogs, the distribution of dead shells, in the main, tracked the distribution of live animals relatively closely. Thus, for both species, the presence of dead shells was a positive indicator of present, recent, or past occupation by live animals. Shell dispersion within habitat was greater for surfclams than for ocean quahogs either due to spatial time averaging, animals not living in all habitable areas all of the time, or parautochthonous redistribution of shell. The regional distribution of dead shell differed from the distribution of live animals, for both species, in a systematic way indicative of range shifts due to climate change. In each case the differential distribution was consistent with warming of the northwest Atlantic. Present-day overlap of live surfclams with live ocean quahogs was consistent with the expectation that the surfclam's range is shifting into deeper water in response to the recent warming trend. The presence of locations devoid of dead shells where live surfclams nevertheless were collected measures the recentness of this event. The presence of dead ocean quahog shells at shallower depths than live ocean quahogs offers good evidence that a range shift has occurred in the past, but prior to the initiation of routine surveys in 1980. Possibly, this range shift tracks initial colonization at the end of the Little Ice Age.
The origin of the Milky Way globular clusters
NASA Astrophysics Data System (ADS)
Renaud, Florent; Agertz, Oscar; Gieles, Mark
2017-03-01
We present a cosmological zoom-in simulation of a Milky Way-like galaxy used to explore the formation and evolution of star clusters. We investigate in particular the origin of the bimodality observed in the colour and metallicity of globular clusters, and the environmental evolution through cosmic times in the form of tidal tensors. Our results self-consistently confirm previous findings that the blue, metal-poor clusters form in satellite galaxies that are accreted on to the Milky Way, while the red, metal-rich clusters form mostly in situ, or, to a lower extent, in massive, self-enriched galaxies merging with the Milky Way. By monitoring the tidal fields these populations experience, we find that clusters formed in situ (generally centrally concentrated) feel significantly stronger tides than the accreted ones, both in the present day, and when averaged over their entire life. Furthermore, we note that the tidal field experienced by Milky Way clusters is significantly weaker in the past than at present day, confirming that it is unlikely that a power-law cluster initial mass function like that of young massive clusters, is transformed into the observed peaked distribution in the Milky Way with relaxation-driven evaporation in a tidal field.
NASA Astrophysics Data System (ADS)
Martin, M. A.; Winkelmann, R.; Haseloff, M.; Albrecht, T.; Bueler, E.; Khroulev, C.; Levermann, A.
2011-09-01
We present a dynamic equilibrium simulation of the ice sheet-shelf system on Antarctica with the Potsdam Parallel Ice Sheet Model (PISM-PIK). The simulation is initialized with present-day conditions for bed topography and ice thickness and then run to steady state with constant present-day surface mass balance. Surface temperature and sub-shelf basal melt distribution are parameterized. Grounding lines and calving fronts are free to evolve, and their modeled equilibrium state is compared to observational data. A physically-motivated calving law based on horizontal spreading rates allows for realistic calving fronts for various types of shelves. Steady-state dynamics including surface velocity and ice flux are analyzed for whole Antarctica and the Ronne-Filchner and Ross ice shelf areas in particular. The results show that the different flow regimes in sheet and shelves, and the transition zone between them, are captured reasonably well, supporting the approach of superposition of SIA and SSA for the representation of fast motion of grounded ice. This approach also leads to a natural emergence of sliding-dominated flow in stream-like features in this new 3-D marine ice sheet model.
Evolution of Lyman-α Emitters, Lyman-break Galaxies and Elliptical Galaxies
NASA Astrophysics Data System (ADS)
Mori, M.; Umemura, M.
2008-10-01
High redshift Lyman-α emitters (LAEs) and Lyman-break galaxies (LBGs) possibly provide a significant key for the embryology of galaxies. LBGs have been argued as candidate progenitors of present-day elliptical galaxies in terms of their observed properties. But, what evolutionary stages LBGs correspond to and how they are related to LAEs are still under debate. Here, we present an ultra-high-resolution hydrodynamic simulation of galaxy formation. We show that, at the earliest stages of less than 3×10^8 years, continual supernova explosions produce multitudinous hot bubbles and cooled HI shells in between. The HI shells radiate intense Lyman-α emission like LAEs. We found that the bubbly structures produced are quite similar to the observed features in the Lyman-α surface brightness distribution of the extended LAEs. After 10^9 years, the galaxy emission is dominated by stellar continuum, exhibiting an LBG-like spectrum. Also, we find that, as a result of purely dynamical evolution over 13 billion years, the properties of this galaxy match those of present-day elliptical galaxies well. It is implied that the major episode of star formation and chemical enrichment in elliptical galaxies is almost completed in the evolutionary path from LAEs to LBGs.
Surface-water radon-222 distribution along the west-central Florida shelf
Smith, C.G.; Robbins, L.L.
2012-01-01
In February 2009 and August 2009, the spatial distribution of radon-222 in surface water was mapped along the west-central Florida shelf as collaboration between the Response of Florida Shelf Ecosystems to Climate Change project and a U.S. Geological Survey Mendenhall Research Fellowship project. This report summarizes the surface distribution of radon-222 from two cruises and evaluates potential physical controls on radon-222 fluxes. Radon-222 is an inert gas produced overwhelmingly in sediment and has a short half-life of 3.8 days; activities in surface water ranged between 30 and 170 becquerels per cubic meter. Overall, radon-222 activities were enriched in nearshore surface waters relative to offshore waters. Dilution in offshore waters is expected to be the cause of the low offshore activities. While thermal stratification of the water column during the August survey may explain higher radon-222 activities relative to the February survey, radon-222 activity and integrated surface-water inventories decreased exponentially from the shoreline during both cruises. By estimating radon-222 evasion by wind from nearby buoy data and accounting for internal production from dissolved radium-226, its radiogenic long-lived parent, a simple one-dimensional model was implemented to determine the role that offshore mixing, benthic influx, and decay have on the distribution of excess radon-222 inventories along the west Florida shelf. For multiple statistically based boundary condition scenarios (first quartile, median, third quartile, and maximum radon-222 inshore of 5 kilometers), the cross-shelf mixing rates and average nearshore submarine groundwater discharge (SGD) rates varied from 100.38 to 10-3.4 square kilometers per day and 0.00 to 1.70 centimeters per day, respectively. This dataset and modeling provide the first attempt to assess cross-shelf mixing and SGD on such a large spatial scale. Such estimates help scale up SGD rates that are often made at 1- to 10-meter resolution to a coarser but more regionally applicable scale of 1- to 10-kilometer resolution. More stringent analyses and model evaluation are required, but results and analyses presented in this report provide the foundation for conducting a more rigorous statistical assessment.
Aerospace Systems Technical Research Operation Services (ASTROS) Industry Day (Briefing Charts)
2014-07-01
Integrated Motor Life Management AFM 315E – Green Propellant MCAT – Missile Component Advanced Tech EP – Electric Propulsion Distribution A...service life estimate •Distribution A: Approved for public release; unlimited distribution 23 MCAT (Motor Component Assessment Technology) What are
NASA Astrophysics Data System (ADS)
John Parkes, R.; Brock, Fiona; Banning, Natasha; Hornibrook, Edward R. C.; Roussel, Erwan G.; Weightman, Andrew J.; Fry, John C.
2012-01-01
A combined biogeochemical and molecular genetic study of creek sediments (down to 65 cm depth) from Arne Peninsula salt-marsh (Dorset, UK) determined the substrates used for methanogenesis and the distribution of the common methanogens, Methanosarcinales and Methanomicrobiales capable of metabolising these substrates. Methane concentrations increased by 11 cm, despite pore water sulphate not being removed until 45 cm. Neither upward methane diffusion or anaerobic oxidation of methane seemed to be important in this zone. In the near-surface sulphate-reduction zone (5-25 cm) turnover time to methane for the non-competitive methanogenic substrate trimethylamine was most rapid (80 days), and were much longer for acetate (7900 days), methanol (40,500 days) and bicarbonate (361,600 days). Methylamine-utilizing Methanosarcinales were the dominant (60-95%) methanogens in this zone. In deeper sediments rates of methanogenesis from competitive substrates increased substantially, with acetate methanogenic rates becoming ˜100 times greater than H 2/CO 2 methanogenesis below 50 cm. In addition, there was a dramatic change in methanogen diversity with obligate acetate-utilizing, Methanosaeta related sequences being dominant. At a similar depth methanol turnover to methane increased to its most rapid (1700 days). This activity pattern is consistent with deeper methanogen populations (55 cm) being dominated by acetate-utilizing Methanosaeta with H 2/CO 2 and alcohol-utilizing Methanomicrobiales also present. Hence, there is close relationship between the depth distribution of methanogenic substrate utilization and specific methanogens that can utilize these compounds. It is unusual for acetate to be the dominant methanogenic substrate in coastal sediments and δ13C-CH 4 values (-74 to -71‰) were atypical for acetate methanogenesis, suggesting that common stable isotope proxy models may not apply well in this type of dynamic anoxic sediment, with multiple methanogenic substrates.
Redefining Tactical Operations for MER Using Cloud Computing
NASA Technical Reports Server (NTRS)
Joswig, Joseph C.; Shams, Khawaja S.
2011-01-01
The Mars Exploration Rover Mission (MER) includes the twin rovers, Spirit and Opportunity, which have been performing geological research and surface exploration since early 2004. The rovers' durability well beyond their original prime mission (90 sols or Martian days) has allowed them to be a valuable platform for scientific research for well over 2000 sols, but as a by-product it has produced new challenges in providing efficient and cost-effective tactical operational planning. An early stage process adaptation was the move to distributed operations as mission scientists returned to their places of work in the summer of 2004, but they would still came together via teleconference and connected software to plan rover activities a few times a week. This distributed model has worked well since, but it requires the purchase, operation, and maintenance of a dedicated infrastructure at the Jet Propulsion Laboratory. This server infrastructure is costly to operate and the periodic nature of its usage (typically heavy usage for 8 hours every 2 days) has made moving to a cloud based tactical infrastructure an extremely tempting proposition. In this paper we will review both past and current implementations of the tactical planning application focusing on remote plan saving and discuss the unique challenges present with long-latency, distributed operations. We then detail the motivations behind our move to cloud based computing services and as well as our system design and implementation. We will discuss security and reliability concerns and how they were addressed
A comparison of dispersing media for various engineered carbon nanoparticles.
Buford, Mary C; Hamilton, Raymond F; Holian, Andrij
2007-07-27
With the increased manufacture and use of carbon nanoparticles (CNP) there has been increasing concern about the potential toxicity of fugitive CNP in the workplace and ambient environment. To address this matter a number of investigators have conducted in vitro and in vivo toxicity assessments. However, a variety of different approaches for suspension of these particles (culture media, Tween 80, dimethyl sulfoxide, phosphate-buffered saline, fetal calf serum, and others), and different sources of materials have generated potentially conflicting outcomes. The quality of the dispersion of nanoparticles is very dependent on the medium used to suspend them, and this then will most likely affect the biological outcomes. In this work, the distributions of different CNP (sources and types) have been characterized in various media. Furthermore, the outcome of instilling the different agglomerates, or size distributions, was examined in mouse lungs after one and seven days. Our results demonstrated that CNP suspended in serum produced particle suspensions with the fewest large agglomerates, and the most uniform distribution in mouse lungs. In addition, no apparent clearance of instilled CNP took place from lungs even after seven days. This work demonstrates that CNP agglomerates are present in all dispersing vehicles to some degree. The vehicle that contains some protein, lipid or protein/lipid component disperses the CNP best, producing fewer large CNP agglomerates. In contrast, vehicles absent of lipid and protein produce the largest CNP agglomerates. The source of the CNP is also a factor in the degree of particle agglomeration within the same vehicle.
NASA Astrophysics Data System (ADS)
Prada, Jose Fernando
Keeping a contingency reserve in power systems is necessary to preserve the security of real-time operations. This work studies two different approaches to the optimal allocation of energy and reserves in the day-ahead generation scheduling process. Part I presents a stochastic security-constrained unit commitment model to co-optimize energy and the locational reserves required to respond to a set of uncertain generation contingencies, using a novel state-based formulation. The model is applied in an offer-based electricity market to allocate contingency reserves throughout the power grid, in order to comply with the N-1 security criterion under transmission congestion. The objective is to minimize expected dispatch and reserve costs, together with post contingency corrective redispatch costs, modeling the probability of generation failure and associated post contingency states. The characteristics of the scheduling problem are exploited to formulate a computationally efficient method, consistent with established operational practices. We simulated the distribution of locational contingency reserves on the IEEE RTS96 system and compared the results with the conventional deterministic method. We found that assigning locational spinning reserves can guarantee an N-1 secure dispatch accounting for transmission congestion at a reasonable extra cost. The simulations also showed little value of allocating downward reserves but sizable operating savings from co-optimizing locational nonspinning reserves. Overall, the results indicate the computational tractability of the proposed method. Part II presents a distributed generation scheduling model to optimally allocate energy and spinning reserves among competing generators in a day-ahead market. The model is based on the coordination between individual generators and a market entity. The proposed method uses forecasting, augmented pricing and locational signals to induce efficient commitment of generators based on firm posted prices. It is price-based but does not rely on multiple iterations, minimizes information exchange and simplifies the market clearing process. Simulations of the distributed method performed on a six-bus test system showed that, using an appropriate set of prices, it is possible to emulate the results of a conventional centralized solution, without need of providing make-whole payments to generators. Likewise, they showed that the distributed method can accommodate transactions with different products and complex security constraints.
A High-resolution 3D Geodynamical Model of the Present-day India-Asia Collision System
NASA Astrophysics Data System (ADS)
Kaus, B.; Baumann, T.
2015-12-01
We present a high-resolution, 3D geodynamic model of the present-day India-Asia collision system. The model is separated into multiple tectonic blocks, for which we estimate the first order rheological properties and the impact on the dynamics of the collision system. This is done by performing systematic simulations with different rheologies to minimize the misfit to observational constraints such as the GPS-velocity field. The simulations are performed with the parallel staggered grid FD code LaMEM using a numerical resolution of at least 512x512x256 cells to resolve dynamically important shear zones reasonably well. A fundamental part of this study is the reconstruction of the 3D present-day geometry of Tibet and the adjacent regions. Our interpretations of crust and mantle lithosphere geometry are jointly based on a globally available shear wave tomography (Schaeffer and Lebedev, 2013) and the Crust 1.0 model (Laske et al. http://igppweb.ucsd.edu/~gabi/crust1.html). We regionally refined and modified our interpretations based on seismicity distributions and focal mechanisms and incorporated regional receiver function studies to improve the accuracy of the Moho in particular. Results suggest that we can identify at least one "best-fit" solution in terms of rheological model properties that reproduces the observed velocity field reasonably well, including the strong rotation of the GPS velocity around the eastern syntax of the Himalaya. We also present model co-variances to illustrate the trade-offs between the rheological model parameters, their respective uncertainties, and the model fit. Schaeffer, A.J., Lebedev, S., 2013. Global shear speed structure of the upper mantle and transition zone. Geophysical Journal International 194, 417-449. doi:10.1093/gji/ggt095
Dong, Sa; Qiao, Kang; Wang, Hongyan; Zhu, Yukun; Xia, Xiaoming; Wang, Kaiyun
2014-08-01
Thiacloprid is a chloronicotinyl insecticide that is quite effective against sucking insects. In this study, when thiacloprid was applied at two different rates (normal rate 15 kg ha(-1) , double rate 30 kg ha(-1) ), the systemic distribution and residue of thiacloprid as well as its control effect against whitefly (Bemisia tabaci) were investigated in greenhouse tomato after soil application. The results showed that thiacloprid was present in the tomato leaves until day 25, and then its amount was less than 0.005 mg kg(-1) and could not be detected. Thiacloprid residue in the tomato stems basically remained at a stable low level throughout the experimental period. Thiacloprid in soil had half-lives of 11.8 and 12.5 days for the normal treatment and the double treatment respectively. The control efficiency of whiteflies was about 90% from day 1 to day 10. This was followed by a slow decline, but efficiency was still higher than 50% until day 21. In addition, no significant differences were noted in the control effect of thiacloprid on whiteflies between the two different rates. Soil application of thiacloprid at the normal rate can effectively control whiteflies, with high efficiency and long persistence. © 2013 Society of Chemical Industry.
Participation of hippocampal agmatine in spatial learning: an in vivo microdialysis study.
Rushaidhi, Madihah; Jing, Yu; Zhang, Hu; Liu, Ping
2013-02-01
Agmatine, decarboxylated arginine, is widely distributed in mammalian brains and is considered as a novel putative neurotransmitter. Recent research demonstrates spatial learning-induced increases in agmatine in memory-related structures at the tissue and presynaptic terminal levels. By using the in vivo microdialysis technique coupled with highly sensitive liquid chromatography/mass spectrometry assay, we investigated dynamic changes of extracellular agmatine in the rat dorsal hippocampus before, during and after water maze training to find a fixed hidden platform on the first and forth day of testing. It was firstly noted that the basal level of extracellular agmatine was significantly elevated on day 4. While swimming per se had no effect, a rapid rise (2-6 folds) in extracellular agmatine was observed during water maze training regardless of testing day. Such learning-induced rise was found to successively lessen across the multiple blocks of training on day 1. However, this pattern was reversed on day 4 when the platform was removed during the final training trial. The present study, for the first time, demonstrates water maze training-induced increase of extracellular agmatine in the dorsal hippocampus. The results suggest a role of endogenous agmatine in the encoding and retrieval of spatial information. Copyright © 2012 Elsevier Ltd. All rights reserved.
40 CFR 80.615 - What penalties apply under this subpart?
Code of Federal Regulations, 2010 CFR
2010-07-01
... specified in section 205 of the Clean Air Act (42 U.S.C. 7524) for every day of each such violation and the... and every day the non-complying diesel fuel remains any place in the distribution system. (2) Any... subject to a separate day of violation for each and every day that the noncomplying fuel remains any place...
NASA Astrophysics Data System (ADS)
Gao, Yu; Lim, Jing; Han, Yiyuan; Wang, Lifeng; Chong, Mark Seow Khoon; Teoh, Swee-Hin; Xu, Chenjie
2016-01-01
Bionanocomposites need to have a homogeneous distribution of nanomaterials in the polymeric matrix to achieve consistent mechanical and biological functions. However, a significant challenge lies in achieving the homogeneous distribution of nanomaterials, particularly through a solvent-free approach. This report introduces a technology to address this need. Specifically, cryomilling, a solvent-free, low-temperature processing method, was applied to generate a bionanocomposite film with well-dispersed nanoparticles. As a proof-of-concept, polycaprolactone (PCL) and doxorubicin-containing silica nanoparticles (Si-Dox) were processed through cryomilling and subsequently heat pressed to form the PCL/Si-Dox (cPCL/Si-Dox) film. Homogeneous distribution of Si-Dox was observed under both confocal imaging and atomic force microscopy imaging. The mechanical properties of cPCL/Si-Dox were comparable to those of the pure PCL film. Subsequent in vitro release profiles suggested that sustained release of Dox from the cPCL/Si-Dox film was achievable over 50 days. When human cervical cancer cells were seeded directly on these films, uptake of Dox was observed as early as day 1 and significant inhibition of cell growth was recorded on day 5.Bionanocomposites need to have a homogeneous distribution of nanomaterials in the polymeric matrix to achieve consistent mechanical and biological functions. However, a significant challenge lies in achieving the homogeneous distribution of nanomaterials, particularly through a solvent-free approach. This report introduces a technology to address this need. Specifically, cryomilling, a solvent-free, low-temperature processing method, was applied to generate a bionanocomposite film with well-dispersed nanoparticles. As a proof-of-concept, polycaprolactone (PCL) and doxorubicin-containing silica nanoparticles (Si-Dox) were processed through cryomilling and subsequently heat pressed to form the PCL/Si-Dox (cPCL/Si-Dox) film. Homogeneous distribution of Si-Dox was observed under both confocal imaging and atomic force microscopy imaging. The mechanical properties of cPCL/Si-Dox were comparable to those of the pure PCL film. Subsequent in vitro release profiles suggested that sustained release of Dox from the cPCL/Si-Dox film was achievable over 50 days. When human cervical cancer cells were seeded directly on these films, uptake of Dox was observed as early as day 1 and significant inhibition of cell growth was recorded on day 5. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr07287e
Analysis of 22,655 presentations with back pain to Perth emergency departments over five years.
Lovegrove, Michael T; Jelinek, George A; Gibson, Nicholas P; Jacobs, Ian G
2011-09-17
Back pain is a significant cause of disability in the community, but the impact on Emergency Departments (EDs) has not been formally studied. Patients with back pain often require significant time and resources in the ED. To examine the characteristics of patients presenting with back pain to the ED, including final diagnosis, demographics of those attending and temporal distribution of presentations. Emergency presentations in the metropolitan area of Perth, Western Australia, for 2000-2004 were searched using a linked database covering all the major hospitals (Emergency Care Hospitalisation and Outcome Study database). All presentations with the triage code for back pain were extracted and analysed. A total of 22,655 presentations with back pain were identified, representing 1.9% of total presentations. Simple muscular or non-specific back pain accounted for only 43.8% of presentations, with other causes such as renal colic and pyelonephritis accounting for the majority. The young (<15 years old) and elderly (>75 years old) were more likely to have non-muscular causes for their back pain. Muscular back pain presentations occurred mostly between 0800 and 1600, with high proportions presenting on the weekends. Patients with simple muscular back pain spent a mean of 4.4 h in the ED, representing a significant outlay of resources. Back pain has a significant impact on EDs, and staff should be alert for another pathology presenting as back pain. There is a need for multidisciplinary back pain teams to be available 7 days a week, but only during the day.
Characterization of within-day beginning times of storms for stochastic simulation
USDA-ARS?s Scientific Manuscript database
The beginning times of storms within a day are often required for stochastic modeling purposes and for studies on plant growth. This study investigated the variation in frequency distributions of storm-initiation time (SI time) within a day due to elevation changes and month. Actual storms without 2...
Does Day Length Affect Winter Bird Distribution? Testing the Role of an Elusive Variable
Carrascal, Luis M.; Santos, Tomás; Tellería, José L.
2012-01-01
Differences in day length may act as a critical factor in bird biology by introducing time constraints in energy acquisition during winter. Thus, differences in day length might operate as a main determinant of bird abundance along latitudinal gradients. This work examines the influence of day length on the abundance of wintering crested tits (Lophophanes cristatus) in 26 localities of Spanish juniper (Juniperus thurifera) dwarf woodlands (average height of 5 m) located along a latitudinal gradient in the Spanish highlands, while controlling for the influence of food availability, minimum night temperature, habitat structure and landscape characteristics. Top regression models in the AIC framework explained 56% of variance in bird numbers. All models incorporated day length as the variable with the highest magnitude effect. Food availability also played an important role, although only the crop of ripe juniper fruits, but not arthropods, positively affected crested tit abundance. Differences in vegetation structure across localities had also a strong positive effect (average tree height and juniper tree density). Geographical variation in night temperature had no influence on crested tit distribution, despite the low winter temperatures reached in these dwarf forests. This paper demonstrates for the first time that winter bird abundance increases with day length after controlling for the effect of other environmental variables. Winter average difference in day length was only 10.5 minutes per day along the 1°47′ latitudinal interval (190 km) included in this study. This amount of time, which reaches 13.5 h accumulated throughout the winter season, appears to be large enough to affect the long-term energy budget of small passerines during winter and to shape the distribution of winter bird abundance under restrictive environmental conditions. PMID:22393442
WIYN OPEN CLUSTER STUDY. XLVIII. THE HARD-BINARY POPULATION OF NGC 188
DOE Office of Scientific and Technical Information (OSTI.GOV)
Geller, Aaron M.; Mathieu, Robert D., E-mail: a-geller@northwestern.edu, E-mail: mathieu@astro.wisc.edu
2012-08-15
We present an in-depth study of the hard-binary population of the old (7 Gyr) open cluster NGC 188. Utilizing 85 spectroscopic binary orbits out of a complete sample of 129 detected binary members, we study the cluster binary frequency and the distributions of binary orbital elements among the main-sequence (MS), giant, and blue straggler (BS) populations. The results are derived from our ongoing radial velocity survey of the cluster, which spans in magnitude from the brightest stars in the cluster to V = 16.5 (about 1.1-0.9 M{sub Sun} ), and extends to a projected radius of 17 pc ({approx}13 coremore » radii). Our detectable binaries have periods ranging from a few days to of order 10{sup 4} days, and thus are hard binaries that dynamically power the cluster. The MS solar-type hard binaries in NGC 188 are nearly indistinguishable from similar binaries in the Galactic field. We observe a global solar-type MS hard-binary frequency in NGC 188 of 23% {+-} 2%, which when corrected for incompleteness results in a frequency of 29% {+-} 3% for binaries with periods less than 10{sup 4} days. For MS hard binaries in the cluster, we observe a log-period distribution that rises toward our detection limit, a roughly Gaussian eccentricity distribution centered on e = 0.35 (for binaries with periods longer than the circularization period), and a secondary-mass distribution that rises toward lower-mass companions. Importantly, the NGC 188 BS binaries show significantly different characteristics than the solar-type MS binaries in NGC 188. We observe a BS hard-binary frequency of 76% {+-} 19%, three times that of the MS. The excess of this binary frequency over the normal MS binary frequency is valid at the >99% confidence level. Furthermore, the BS binary eccentricity-log-period distribution is distinct from that of the MS at the 99% confidence level, with the majority of the BS binaries having periods of order 1000 days and lower eccentricities. The secondary-mass distribution for these long-period BS binaries is narrow and peaked with a mean value of about 0.5 M{sub Sun }. Predictions for mass-transfer products are most closely consistent with the binary properties of these NGC 188 BSs, which comprise two-thirds of the BS population. Additionally, we compare the NGC 188 binaries to those evolved within the sophisticated Hurley et al. (2005) N-body open cluster simulation. The MS hard-binary population predicted by the simulation is significantly different from the MS hard-binary population observed in NGC 188, in frequency and distributions of period and eccentricity. Many of these differences result from the adopted initial binary population, while others reflect on the physics used in the simulation (e.g., tidal circularization). Additional simulations with initial conditions that are better motivated by observations are necessary to properly investigate the dynamical evolution of a rich binary population in open clusters like NGC 188.« less
Geo-Engineering Climate Change with Sulfate Aerosol
NASA Astrophysics Data System (ADS)
Rasch, P. J.; Crutzen, P. J.
2006-12-01
We explore the impact of injecting a precursor of sulfate aerosols into the middle atmosphere where they would act to increase the planetary albedo and thus counter some of the effects of greenhouse gase forcing. We use an atmospheric general circulation model (CAM, the Community Atmosphere Model) coupled to a slab ocean model for this study. Only physical effects are examined, that is we ignore the biogeochemical and chemical implications of changes to greenhouse gases and aerosols, and do not explore the important ethical, legal, and moral issues that are associated with deliberate geo-engineering efforts. The simulations suggest that the sulfate aerosol produced from the SO2 source in the stratosphere is sufficient to counterbalance most of the warming associated with the greenhouse gas forcing. Surface temperatures return to within a few tenths of a degree(K) of present day levels. Sea ice and precipitation distributions are also much closer to their present day values. The polar region surface temperatures remain 1-3 degrees warm in the winter hemisphere than present day values. This study is very preliminary. Only a subset of the relevant effects have been explored. The effect of such an injection of aerosols on middle atmospheric chemistry, and the effect on cirrus clouds are obvious missing components that merit scrutiny. There are probably others that should be considered. The injection of such aerosols cannot help in ameliorating the effects of CO2 changes on ocean PH, or other effects on the biogeochemistry of the earth system.
Selker, Frank; Selker, John S.
2018-01-01
There are few methods to provide high-resolution in-situ characterization of flow in aquifers and reservoirs. We present a method that has the potential to quantify lateral and vertical (magnitude and direction) components of flow with spatial resolution of about one meter and temporal resolution of about one day. A fiber optic distributed temperature sensor is used with a novel heating system. Temperatures before heating may be used to evaluate background geothermal gradient and vertical profile of thermal diffusivity. The innovation presented is the use of variable energy application along the well, in this case concentrated heating at equally-spaced (2 m) localized areas (0.5 m). Relative to uniform warming this offers greater opportunity to estimate water movement, reduces required heating power, and increases practical length that can be heated. Numerical simulations are presented which illustrate expected behaviors. We estimate relative advection rates near the well using the times at which various locations diverge from a heating trajectory expected for pure conduction in the absence of advection. The concept is demonstrated in a grouted 600 m borehole with 300 heated patches, though evidence of vertical water movement was not seen. PMID:29596339
Selker, Frank; Selker, John S
2018-03-29
There are few methods to provide high-resolution in-situ characterization of flow in aquifers and reservoirs. We present a method that has the potential to quantify lateral and vertical (magnitude and direction) components of flow with spatial resolution of about one meter and temporal resolution of about one day. A fiber optic distributed temperature sensor is used with a novel heating system. Temperatures before heating may be used to evaluate background geothermal gradient and vertical profile of thermal diffusivity. The innovation presented is the use of variable energy application along the well, in this case concentrated heating at equally-spaced (2 m) localized areas (0.5 m). Relative to uniform warming this offers greater opportunity to estimate water movement, reduces required heating power, and increases practical length that can be heated. Numerical simulations are presented which illustrate expected behaviors. We estimate relative advection rates near the well using the times at which various locations diverge from a heating trajectory expected for pure conduction in the absence of advection. The concept is demonstrated in a grouted 600 m borehole with 300 heated patches, though evidence of vertical water movement was not seen.
Water distribution at the root-soil interface: is there more water next to roots?
NASA Astrophysics Data System (ADS)
Carminati, A.; Moradi, A.; Oswald, S.; Vetterlein, D.; Weller, U.; Vogel, H.-J.
2009-04-01
Plants are big water movers and have a significant impact on soil water dynamics as well as on the global water cycle. Despite the relevance of root water uptake in terrestrial ecology, the movement of water from soil to roots still presents important open questions, e.g the following two. Which are the properties of the soil near the roots? And what effect do these properties have on soil plant water relations? Most models are based on brute-force spatial averaging of soil properties and assume that the bulk soil has the same properties as the rhizosphere. However, there is evidence in the literature that the rhizosphere has specific properties that may affect water and nutrient uptake (Young 1995, Gregory 2007). In order to investigate the rhizosphere hydraulic properties and their effect on soil plant water relations, we used neutron radiography and neutron tomography to image the water content distribution in soils during plant transpiration. Rectangular (quasi-2D) and cylindrical containers were filled with sandy soil and planted with lupins (Lupinus albus). Three weeks after planting, the samples were equilibrated at water potentials of -10 and 30 hPa and have been imaged for 5 days at intervals of 6 hours. At day 5 the samples were irrigated again via capillary rise and the water distribution was monitored for 4 more days. During the first day of the drying period, regions of water depletion formed around the central part of the tap root where first order laterals were present. As the soil dried up, the picture changed: instead of less water around the roots, as commonly supposed by models, we observed that more water was present around the lateral roots. Interestingly, these regions during drying were retaining high water content, but after irrigation remained markedly drier than the bulk soil. Our hypothesis is that high water content near roots during drying and lower water content during rewetting are explained by the presence of bio-polymers exuded by roots forming a hydrogel that consists of up to 99% water at very negative water potentials (Read et al. 1999). Thanks to its high water holding capacity, this hydrogel maintains a continuous hydraulic pathway across soil and roots for an extended period of time during drying. During rewetting it adversely affects water redistribution, like a storage that needs time to fill up again. These data show for the first time in situ the potential role of mucilage in controlling water dynamics in the rhizosphere and consequences for plant water extraction. Gregory P J, Roots, rhizosphere and soil: the route to a better understanding of soil science? European Journal of Soil Science, 57: 2-12, 2006. Read D P, Gregory P J, and Bell A E. Physical properties of axenic maize root mucilage. Plant and Soil, 211: 87-91, 1999. Young I M. Variation in moisture contents between bulk soil and the rhizosheath of wheat. New Phytologist, 130: 135-139, 1995.
The Future of the Andrew File System
Brashear, Drrick; Altman, Jeffry
2018-05-25
The talk will discuss the ten operational capabilities that have made AFS unique in the distributed file system space and how these capabilities are being expanded upon to meet the needs of the 21st century. Derrick Brashear and Jeffrey Altman will present a technical road map of new features and technical innovations that are under development by the OpenAFS community and Your File System, Inc. funded by a U.S. Department of Energy Small Business Innovative Research grant. The talk will end with a comparison of AFS to its modern days competitors.
Delta Ori Phase-Dependent Variability from Chandra and MOST Campaign
NASA Astrophysics Data System (ADS)
Nichols, Joy; Naze, Yael; Moffatt, Anthony F. J.; Corcoran, Michael; Richardson, Noel; Williams, S.; Pollock, A. M. T.; Ignace, Richard; Hole, T.; Waldron, W.; Evans, Nancy Remage; MOST Collaboration
2013-06-01
We report preliminary results from variability analysis of delta Ori in Chandra high-resolution X-ray spectroscopy and concurrent MOST high-precision optical photometry. With nearly complete phase coverage of the 5-day eclipsing binary orbit, it is possible to measure directly radial velocity and flux variations as a function of phase, leading to a mapping of the stellar wind distribution for the massive primary star. The phase dependence of the X-ray overall intensity and the comparative behavior of the emission lines are also presented.
The Future of the Andrew File System
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brashear, Drrick; Altman, Jeffry
2011-02-23
The talk will discuss the ten operational capabilities that have made AFS unique in the distributed file system space and how these capabilities are being expanded upon to meet the needs of the 21st century. Derrick Brashear and Jeffrey Altman will present a technical road map of new features and technical innovations that are under development by the OpenAFS community and Your File System, Inc. funded by a U.S. Department of Energy Small Business Innovative Research grant. The talk will end with a comparison of AFS to its modern days competitors.
Hauge, Erik; Berle, Jan Øystein; Dilsaver, Steven; Oedegaard, Ketil J.
2016-01-01
Objective Alterations of activity are prominent features of the major functional psychiatric disorders. Motor activity patterns are characterized by bursts of activity separated by periods with inactivity. The purpose of the present study has been to analyze such active and inactive periods in patients with depression and schizophrenia. Methods Actigraph registrations for 12 days from 24 patients with schizophrenia, 23 with depression and 29 healthy controls. Results Patients with schizophrenia and depression have distinctly different profiles with regard to the characterization and distribution of active and inactive periods. The mean duration of active periods is lowest in the depressed patients, and the duration of inactive periods is highest in the patients with schizophrenia. For active periods the cumulative probability distribution, using lengths from 1 to 35 min, follows a straight line on a log-log plot, suggestive of a power law function, and a similar relationship is found for inactive periods, using lengths from 1 to 20 min. For both active and inactive periods the scaling exponent is higher in the depressed compared to the schizophrenic patients. Conclusion The present findings add to previously published results, with other mathematical methods, suggesting there are important differences in control systems regulating motor behavior in these two major groups of psychiatric disorders. PMID:26766953
Multicomponent plasma expansion into vacuum with non-Maxwellian electrons
NASA Astrophysics Data System (ADS)
Elkamash, Ibrahem; Kourakis, Ioannis
2016-10-01
The expansion of a collisionless plasma into vacuum has been widely studied since the early works of Gurevich et al and Allen and coworkers. It has received momentum in recent years, in particular in the context of ultraintense laser pulse interaction with a solid target, in an effort to elucidate the generation of high energy ion beams. In most present day experiments, laser produced plasmas contain several ion species, due to increasingly complicated composite targets. Anderson et al have studied the isothermal expansion of a two-ion-species plasma. As in most earlier works, the electrons were assumed to be isothermal throughout the expansion. However, in more realistic situations, the evolution of laser produced plasmas into vacuum is mainly governed by nonthermal electrons. These electrons are characterized by particle distribution functions with high energy tails, which may significantly deviate from the Maxwellian distribution. In this paper, we present a theoretical model for plasma expansion of two component plasma with nonthermal electrons, modelled by a kappa-type distribution. The superthermal effect on the ion density, velocity and the electric field is investigated. It is shown that energetic electrons have a significant effecton the expansion dynamics of the plasma. This work was supported from CPP/QUB funding. One of us (I.S. Elkamash) acknowledges financial support by an Egyptian Government fellowship.
Tectonics, climate, and the rise and demise of continental aquatic species richness hotspots.
Neubauer, Thomas A; Harzhauser, Mathias; Georgopoulou, Elisavet; Kroh, Andreas; Mandic, Oleg
2015-09-15
Continental aquatic species richness hotspots are unevenly distributed across the planet. In present-day Europe, only two centers of biodiversity exist (Lake Ohrid on the Balkans and the Caspian Sea). During the Neogene, a wide variety of hotspots developed in a series of long-lived lakes. The mechanisms underlying the presence of richness hotspots in different geological periods have not been properly examined thus far. Based on Miocene to Recent gastropod distributions, we show that the existence and evolution of such hotspots in inland-water systems are tightly linked to the geodynamic history of the European continent. Both past and present hotspots are related to the formation and persistence of long-lived lake systems in geological basins or to isolation of existing inland basins and embayments from the marine realm. The faunal evolution within hotspots highly depends on warm climates and surface area. During the Quaternary icehouse climate and extensive glaciations, limnic biodiversity sustained a severe decline across the continent and most former hotspots disappeared. The Recent gastropod distribution is mainly a geologically young pattern formed after the Last Glacial Maximum (19 ky) and subsequent formation of postglacial lakes. The major hotspots today are related to long-lived lakes in preglacially formed, permanently subsiding geological basins.
Tectonics, climate, and the rise and demise of continental aquatic species richness hotspots
Neubauer, Thomas A.; Harzhauser, Mathias; Georgopoulou, Elisavet; Kroh, Andreas; Mandic, Oleg
2015-01-01
Continental aquatic species richness hotspots are unevenly distributed across the planet. In present-day Europe, only two centers of biodiversity exist (Lake Ohrid on the Balkans and the Caspian Sea). During the Neogene, a wide variety of hotspots developed in a series of long-lived lakes. The mechanisms underlying the presence of richness hotspots in different geological periods have not been properly examined thus far. Based on Miocene to Recent gastropod distributions, we show that the existence and evolution of such hotspots in inland-water systems are tightly linked to the geodynamic history of the European continent. Both past and present hotspots are related to the formation and persistence of long-lived lake systems in geological basins or to isolation of existing inland basins and embayments from the marine realm. The faunal evolution within hotspots highly depends on warm climates and surface area. During the Quaternary icehouse climate and extensive glaciations, limnic biodiversity sustained a severe decline across the continent and most former hotspots disappeared. The Recent gastropod distribution is mainly a geologically young pattern formed after the Last Glacial Maximum (19 ky) and subsequent formation of postglacial lakes. The major hotspots today are related to long-lived lakes in preglacially formed, permanently subsiding geological basins. PMID:26305934
Pinkernell, Stefan; Beszteri, Bánk
2014-08-01
Fragilariopsis kerguelensis, a dominant diatom species throughout the Antarctic Circumpolar Current, is coined to be one of the main drivers of the biological silicate pump. Here, we study the distribution of this important species and expected consequences of climate change upon it, using correlative species distribution modeling and publicly available presence-only data. As experience with SDM is scarce for marine phytoplankton, this also serves as a pilot study for this organism group. We used the maximum entropy method to calculate distribution models for the diatom F. kerguelensis based on yearly and monthly environmental data (sea surface temperature, salinity, nitrate and silicate concentrations). Observation data were harvested from GBIF and the Global Diatom Database, and for further analyses also from the Hustedt Diatom Collection (BRM). The models were projected on current yearly and seasonal environmental data to study current distribution and its seasonality. Furthermore, we projected the seasonal model on future environmental data obtained from climate models for the year 2100. Projected on current yearly averaged environmental data, all models showed similar distribution patterns for F. kerguelensis. The monthly model showed seasonality, for example, a shift of the southern distribution boundary toward the north in the winter. Projections on future scenarios resulted in a moderately to negligibly shrinking distribution area and a change in seasonality. We found a substantial bias in the publicly available observation datasets, which could be reduced by additional observation records we obtained from the Hustedt Diatom Collection. Present-day distribution patterns inferred from the models coincided well with background knowledge and previous reports about F. kerguelensis distribution, showing that maximum entropy-based distribution models are suitable to map distribution patterns for oceanic planktonic organisms. Our scenario projections indicate moderate effects of climate change upon the biogeography of F. kerguelensis.
NASA Technical Reports Server (NTRS)
Fennessey, N. M.; Eagleson, P. S.; Qinliang, W.; Rodriguez-Iturbe, I.
1986-01-01
The parameters of the conceptual model are evaluated from the analysis of eight years of summer rainstorm data from the dense raingage network in the Walnut Gulch catchment near Tucson, Arizona. The occurrence of measurable rain at any one of the 93 gages during a noon to noon day defined a storm. The total rainfall at each of the gages during a storm day constituted the data set for a single storm. The data are interpolated onto a fine grid and analyzed to obtain: an isohyetal plot at 2 mm intervals, the first three moments of point storm depth, the spatial correlation function, the spatial variance function, and the spatial distribution of the total storm depth. The description of the data analysis and the computer programs necessary to read the associated data tapes are presented.
Jain, Nikhil; Phillips, Frank M; Khan, Safdar N
2018-04-01
A retrospective, economic analysis. The objective of this article is to analyze the distribution of 90-day payments, sources of variation, and reimbursement for complications and readmissions for primary ≥3-level posterior lumbar fusion (PLF) from Medicare data. A secondary objective was to identify risk factors for complications. Bundled payments represent a single payment system to cover all costs associated with a single episode of care, typically over 90 days. The dollar amount spent on different health service providers and the variation in payments for ≥3-level PLF have not been analyzed from a bundled perspective. Administrative claims data were used to study 90-day Medicare (2005-2012) reimbursements for primary ≥3-level PLF for deformity and degenerative conditions of the lumbar spine. Distribution of payments, sources of variation, and reimbursements for managing complications were studied using linear regression models. Risk factors for complications were studied by stepwise multiple-variable logistic regression analysis. Hospital payments comprised 73.8% share of total 90-day payment. Adjusted analysis identified several factors for variation in index hospital payments. The average 90-day Medicare payment for all multilevel PLFs without complications was $35,878 per patient. The additional average cost of treating complications with/without revision surgery within 90 days period ranged from $17,284 to $68,963. A 90-day bundle for ≥3-level PLF with readmission ranges from $88,648 (3 levels) to $117,215 (8+ levels). Rates and risk factors for complications were also identified. The average 90-day payment per patient from Medicare was $35,878 with several factors such as levels of surgery, comorbidities, and development of complications influencing the cost. The study also identifies the risks and costs associated with complications and readmissions and emphasize the significant effect these would have on bundled payments (additional burden of up to 192% the cost of an average uncomplicated procedure over 90 days). Level 3.
Dietz, Patricia M; England, Lucinda J; Callaghan, William M; Pearl, Michelle; Wier, Megan L; Kharrazi, Martin
2007-09-01
Although early ultrasound (<20 weeks' gestation) systematically underestimates the gestational age of smaller fetuses by approximately 1-2 days, this bias is relatively small compared with the large error introduced by last menstrual period (LMP) estimates of gestation, as evidenced by the number of implausible birthweight-for-gestational age. To characterise this misclassification, we compared gestational age estimates based on LMP from California birth certificates with those based on early ultrasound from a California linked Statewide Expanded Alpha-fetoprotein Screening Program (XAFP). The final sample comprised 165 908 women. Birthweight distributions were plotted by gestational age; sensitivity and positive predictive value for preterm rates according to LMP were calculated using ultrasound as the 'gold standard'. For gestational ages 20-27 and 28-31 weeks, the LMP-based birthweight distributions were bimodal, whereas the ultrasound-based distributions were unimodal, but had long right tails. At 32-36 weeks, the LMP distribution was wider, flatter, and shifted to the right, compared with the ultrasound distribution. LMP vs. ultrasound estimates were, respectively, 8.7% vs. 7.9% preterm (<37 weeks), 81.2% vs. 91.0% term (37-41 weeks), and 10.1% vs. 1.1% post-term (>or=42 weeks). The sensitivity of the LMP-based preterm birth estimate was 64.3%, and the positive predictive value was 58.7%. Overall, 17.2% of the records had estimates with an absolute difference of >14 days. The groups most likely to have inconsistent gestational age estimates included African American and Hispanic women, younger and less-educated women, and those who entered prenatal care after the second month of pregnancy. In conclusion, we found substantial misclassification of LMP-based gestational age. The 2003 revised US Standard Certificate of Live Birth includes a new gestational age item, the obstetric estimate. It will be important to assess whether this estimate addresses the problems presented by LMP-based gestational age.
Brewer, Shannon K.; Worthington, Thomas A.; Zhang, Tianjioa; Logue, Daniel R.; Mittelstet, Aaron R.
2016-01-01
Truncated distributions of pelagophilic fishes have been observed across the Great Plains of North America, with water use and landscape fragmentation implicated as contributing factors. Developing conservation strategies for these species is hindered by the existence of multiple competing flow regime hypotheses related to species persistence. Our primary study objective was to compare the predicted distributions of one pelagophil, the Arkansas River Shiner Notropis girardi, constructed using different flow regime metrics. Further, we investigated different approaches for improving temporal transferability of the species distribution model (SDM). We compared four hypotheses: mean annual flow (a baseline), the 75th percentile of daily flow, the number of zero-flow days, and the number of days above 55th percentile flows, to examine the relative importance of flows during the spawning period. Building on an earlier SDM, we added covariates that quantified wells in each catchment, point source discharges, and non-native species presence to a structured variable framework. We assessed the effects on model transferability and fit by reducing multicollinearity using Spearman’s rank correlations, variance inflation factors, and principal component analysis, as well as altering the regularization coefficient (β) within MaxEnt. The 75th percentile of daily flow was the most important flow metric related to structuring the species distribution. The number of wells and point source discharges were also highly ranked. At the default level of β, model transferability was improved using all methods to reduce collinearity; however, at higher levels of β, the correlation method performed best. Using β = 5 provided the best model transferability, while retaining the majority of variables that contributed 95% to the model. This study provides a workflow for improving model transferability and also presents water-management options that may be considered to improve the conservation status of pelagophils.
Multiscale thermal refugia and stream habitat associations of chinook salmon in northwestern Oregon
Torgersen, Christian E.; Price, David M.; Li, Hiram W.; McIntosh, B.A.
1999-01-01
We quantified distribution and behavior of adult spring chinook salmon (Oncorhynchus tshawytscha) related to patterns of stream temperature and physical habitat at channel-unit, reach-, and section-level spatial scales in a wilderness stream and a disturbed stream in the John Day River basin in northeastern Oregon. We investigated the effectiveness of thermal remote sensing for analyzing spatial patterns of stream temperature and assessed habitat selection by spring chinook salmon, evaluating whether thermal refugia might be responsible for the persistence of these stocks in rivers where water temperatures frequently exceed their upper tolerance levels (25A?C) during spawning migration. By presenting stream temperature and the ecology of chinook salmon in a historical context, we could evaluate how changes in riverine habitat and thermal spatial structure, which can be caused by land-use practices, may influence distributional patterns of chinook salmon. Thermal remote sensing provided spatially continuous maps of stream temperature for reaches used by chinook salmon in the upper subbasins of the Middle Fork and North Fork John Day River. Electivity analysis and logistic regression were used to test for associations between the longitudinal distribution of salmon and cool-water areas and stream habitat characteristics. Chinook salmon were distributed nonuniformly in reaches throughout each stream. Salmon distribution and cool water temperature patterns were most strongly related at reach-level spatial scales in the warm stream, the Middle Fork (maximum likelihood ratio: P 0.30). Pools were preferred by adult chinook salmon in both subbasins (Bonferroni confidence interval: P a?? 0.05); however, riffles were used proportionately more frequently in the North Fork than in the Middle Fork. Our observations of thermal refugia and their use by chinook salmon at multiple spatial scales reveal that, although heterogeneity in the longitudinal stream temperature profile may be viewed as an ecological warning sign, thermal patchiness in streams also should be recognized for its biological potential to provide habitat for species existing at the margin of their environmental tolerances.
Chronic eosinophilic pneumonia presenting with ipsilateral pleural effusion: a case report.
Sriratanaviriyakul, Narin; La, Hanh H; Albertson, Timothy E
2016-08-12
Chronic eosinophilic pneumonia is a rare idiopathic interstitial lung disease. The nearly pathognomonic radiographic finding is the peripheral distribution of alveolar opacities. Pleural effusions are rarely seen. We report a case of chronic eosinophilic pneumonia with transudative eosinophilic pleural effusion. A 57-year-old Hispanic woman, a nonsmoker with a history of controlled asthma, presented to the hospital with unresolving pneumonia despite three rounds of antibiotics over a 2-month period. She was later diagnosed with chronic eosinophilic pneumonia based on the presence of peripheral blood eosinophilia, the peripheral distribution of alveolar infiltrates on chest radiograph, and a lung parenchymal biopsy with infiltrates of eosinophils. Upon presentation, our patient had a right-sided moderate-sized pleural effusion. The pleural fluid profile was consistent with a transudative effusion with eosinophil predominance. Our patient responded promptly to oral corticosteroid treatment in a few days. The pulmonary infiltrates and pleural effusion subsided on a 1-month follow-up chest radiograph after starting corticosteroid treatment. We report the first case of chronic eosinophilic pneumonia presenting with pneumonia with ipsilateral transudative eosinophilic pleural effusion. Like other cases of chronic eosinophilic pneumonia, early recognition and diagnosis is essential and prompt treatment with corticosteroids is the mainstay of therapy. Pleural effusion resolved without the further need for therapeutic thoracentesis.
The estimation of probable maximum precipitation: the case of Catalonia.
Casas, M Carmen; Rodríguez, Raül; Nieto, Raquel; Redaño, Angel
2008-12-01
A brief overview of the different techniques used to estimate the probable maximum precipitation (PMP) is presented. As a particular case, the 1-day PMP over Catalonia has been calculated and mapped with a high spatial resolution. For this purpose, the annual maximum daily rainfall series from 145 pluviometric stations of the Instituto Nacional de Meteorología (Spanish Weather Service) in Catalonia have been analyzed. In order to obtain values of PMP, an enveloping frequency factor curve based on the actual rainfall data of stations in the region has been developed. This enveloping curve has been used to estimate 1-day PMP values of all the 145 stations. Applying the Cressman method, the spatial analysis of these values has been achieved. Monthly precipitation climatological data, obtained from the application of Geographic Information Systems techniques, have been used as the initial field for the analysis. The 1-day PMP at 1 km(2) spatial resolution over Catalonia has been objectively determined, varying from 200 to 550 mm. Structures with wavelength longer than approximately 35 km can be identified and, despite their general concordance, the obtained 1-day PMP spatial distribution shows remarkable differences compared to the annual mean precipitation arrangement over Catalonia.
Effect of exercise on the maternal outcome in pregnancy of spontaneously hypertensive rats.
Rocha, Renato; Peraçoli, José Carlos; Volpato, Gustavo Tadeu; Damasceno, Débora Cristina; Campos, Kleber Eduardo de
2014-09-01
To evaluate the effect of exercise (swimming) on pregnancy in spontaneously hypertensive rats (SHR). Thirty three pregnant female SHR were distributed into three groups (n=11 animals/group): SHR Control=non-exercised (sedentary); SHR Ex0 = exercised from day zero to day 20 of pregnancy; and SHR Ex7 = exercised from day 7 to 20 of pregnancy. Body weight and systolic blood pressure were indirectly measured during pregnancy. On gestational day 21, the rats were anaesthetized and uterine content was withdrawn for analysis of maternal reproductive outcome parameters and fetal development. The reduced blood pressure percentage was higher in SHR Ex0 and SHR Ex7 compared to SHR Control group. Weight gain was present in all pregnancy periods, but it was lower in SHR Ex7 than in SHR Control dams. The exercise increased the pre-implantation loss rate. The post-implantation loss rate was lower in SHR Ex0 group. SHR Ex7 group showed a significantly higher percentage of fetuses classified as small for gestational age as compared to others groups. The exercise contributed to lowering gestational blood pressure in SHR rats, but had a negative impact on the developing embryo.
NASA Astrophysics Data System (ADS)
de Oliveira, Susana Carla Pires Sampaio; de Carvalho Monteiro, Juliana Santos; dos Santos Aciole, Gilberth Tadeu; DeCastro, Isabele Cardoso V.; Menezes, Diego Silva; de Fátima Lima Ferreira, Maria; dos Santos, Jean Nunes; Zanin, Fátima; Barbosa Pinheiro, Antônio Luiz
2010-05-01
Iron deficiency anemia causes reduction on the level of hemoglobin and of the number of RBC and affects around 35% of the human population. Laser and LED therapies have been successfully used on wound healing studies. The aim of the present study was to assess histologically the effect of LED Phototherapy on the healing of cutaneous wounds on anemic rats. Fifty one 21 days old male wistar rats weighting around 50 g were kept under iron free die (Sem ferro-AIN93-G) during 15 days in order to induce anemia. Non treated animals acted as controls. A standartized cutaneous wound was created on the dorsum of each animal whom were distributed into four groups: Group I—Anemia+LED, Group II—Non anemic+LED, Group III—Anemia+no treatment, Group IV—No anemic+no-treatment. Irradiation started immediately after surgery and repeated at 48 h intervals during 21 days. Animal death occurred after 7, 14 and 21 days after wounding. The results of the histologic analysis showed that LED Phototherapy stimulated fibroblastic proliferation. It is concluded that LED irradiation improves wound healing on iron deficient anemic animals.
The variability of SE2 tide extracted from TIMED/SABER observations
NASA Astrophysics Data System (ADS)
Li, Xing; Wan, Weixing; Ren, Zhipeng; Yu, You
2017-04-01
Based on the temperature observations of the SABER/TIMED, the variability of the non-migrating tide SE2 with high resolution (one-day) is analyzed, using the method from Li et al., [2015]. From the temperature observation data measured in the mesosphere and lower atmosphere region (MLT, 70-110 km altitudes) and at the low- and mid -latitudes (45S - 45N) from2002 to 2012), we obtained the non-migrating tide SE2 and further studied it in detail. It is found that the climatological features (large time scale variability and spatial distribution) of the SE2 tidal component are similar with the results from the previous researches, which are picked up from the interpolated data with 60-day resolution. The climatological features are that the SE2 tidal component manifests mainly at the low-mid latitudes around 30. The northern hemisphere tidal amplitudes below 110 km are larger than the southern hemisphere tide, at the same time, its peaks below 110 km mainly present between 100 and 110 km altitude; the tidal amplitudes below 110 km occur a north-south asymmetry about the equator in the annual variation: in the southern hemisphere, SE2 occurs with an obvious annual variation with a maximum of tidal amplitudes in December; while, in the northern one, the semi-annual variations with maximum at the equinoxes are stronger than that in the southern one. Herein, owing to the high-resolution tidal data (one day), we could research the short term (day-to-day) variations of the SE2 tide. We found that: (1) the day-to-day variations manifests mainly at the altitudes range between 100 and 110 km; (2) it increases gradually with latitudes and it is stronger at the low-mid latitudes; (3) it is relatively slightly stronger around solstices than equinoxes; (4) it does not present a remarkably inter-annual variation. Finally, the SE2 day-to-day variations may be composed by the absolute amplitudes' variance and the impact of the wave phases. In addition, the variations of variance are more important.
Analysis of dust storms observed in Mongolia during 1937-1999
NASA Astrophysics Data System (ADS)
Natsagdorj, L.; Jugder, D.; Chung, Y. S.
Climatology of dust storms in Mongolia is compiled based on observational data of 49 meteorological stations from 1960 to 1999 and compared them with data between 1937 and 1989. Three different maps of the distribution of dust storms, drifting dust and the number of dusty days are presented. The results of the analysis show that the number of days with dust storms is <5 days over the Altai, the Khangai and the Khentei mountainous regions and more than 20-37 days in the Gobi Desert and semi-desert area. The greatest occurrence of drifting dust arises around the Mongol Els area of west Mongolia. The number of dusty days, which is derived from the sum of the number of days with dust storms and drifting dust, is <10 days in the mountainous area and 61-127 days in the Gobi Desert and the Great Lakes hollow of west Mongolia. It is found that 61% of dust storms occur in the spring in Mongolia and a dust storm lasts on average from 3.1 to 6.0 h. About 65.5-91.0% of dust storms occur in daytime and 9.0-34.5% at night. Dust storms occur more frequently in the city region and are accompanied by surface wind speeds usually from 6 to 20 ms -1. Dust storms usually occur when soil and air are dry, and 70% of dust storms occur in dry soil conditions. When dust storms occur, relative humidity averages 20-40% in Mongolia. An important outcome of this study is the trend of dusty days between 1960 and 1999. It shows that the number of dusty days has tripled from the 1960s to 1990s and has decreased since 1990.
Naughton, Robert J; Drust, Barry; O'Boyle, Andy; Morgans, Ryland; Abayomi, Julie; Davies, Ian G; Morton, James P; Mahon, Elizabeth
2016-10-01
While traditional approaches to dietary analysis in athletes have focused on total daily energy and macronutrient intake, it is now thought that daily distribution of these parameters can also influence training adaptations. Using 7-day food diaries, we quantified the total daily macronutrient intake and distribution in elite youth soccer players from the English Premier League in U18 (n = 13), U15/16 (n = 25) and U13/14 squads (n = 21). Total energy (43.1 ± 10.3, 32.6 ± 7.9, 28.1 ± 6.8 kcal·kg -1 ·day -1 ), CHO (6 ± 1.2, 4.7 ± 1.4, 3.2 ± 1.3 g·kg - 1 ·day -1 ) and fat (1.3 ± 0.5, 0.9 ± 0.3, 0.9 ± 0.3 g·kg- 1 ·day -1 ) intake exhibited hierarchical differences (p < .05) such that U13/14 > U15/16 > U18. In addition, CHO intake in U18s was lower (p < .05) at breakfast, dinner and snacks when compared with both squads but no differences were apparent at lunch. Furthermore, the U15/16s reported lower relative daily protein intake than the U13/14s and U18s (1.6 ± 0.3 vs. 2.2 ± 0.5, 2.0 ± 0.3 g·kg -1 ). A skewed distribution (p < .05) of daily protein intake was observed in all squads, with a hierarchical order of dinner (~0.6 g·kg -1 ) > lunch (~0.5 g·kg -1 ) > breakfast (~0.3 g·kg -1 ). We conclude elite youth soccer players do not meet current CHO guidelines. Although daily protein targets are achieved, we report a skewed daily distribution in all ages such that dinner > lunch > breakfast. Our data suggest that dietary advice for elite youth players should focus on both total daily macronutrient intake and optimal daily distribution patterns.
NASA Astrophysics Data System (ADS)
Koch, Axelle; Schröder, Natalie; Pohlmeier, Andreas; Garré, Sarah; Vanderborght, Jan; Javaux, Mathieu
2017-04-01
Measuring water extraction by plant would allow us to better understand root water uptake processes and how soil and plant properties affect them. Yet, direct measurement of root water uptake is still challenging and determining its distribution requires coupling experimentation and modelling. In this study, we investigated how the 3D monitoring of a tracer movement in a sand container with a lupine plant could inform us about root water uptake process. A sand column (10 cm height, 5 cm inner diameter) planted with an 18-day-old white lupine was subject to a tracer experiment with a chemically inert tracer (1 mmol/L Gd-DTPA2-) applied for 6 days. Then the tracer and water fluxes were stopped. The plume was monitored in 3-D for 7 days by Magnetic Resonance Imaging (Haber-Pohlmeier et al, unp). In addition the breakthrough curve at the outlet was also measured. We used a biophysical 3-D soil-plant model: R-SWMS (Javaux et al, 2008) to extract information from this experiment. First, we ran a virtual experiment to check the assumption that Gd concentration increase around roots is proportional to the extracted soil water during the same period. We also investigated whether this type of experiment helps discriminate different root hydraulic properties with a sensitivity analysis. Then, we compared the experimental and simulated Gd concentration patterns. A preliminary (qualitative) assessment showed that measured Gd distribution patterns were better represented by the model at day 7, where the main driver of the concentration distribution was root and not soil heterogeneity (which is not taken into account in the model). The main spatial and temporal features of the transport where adequately reproduced by the model in particular during the last day. The distribution of the tracer was shown to be sensitive to the root hydraulic properties. To conclude, information about root water uptake distributions and so about root hydraulic properties could be deduced from Gd concentration maps. Keywords: R-SWMS; Modelling; MRI; Root Water Uptake; Gadolinium
NASA Technical Reports Server (NTRS)
Naik, V.; Voulgarakis, A.; Fiore, A. M.; Horowitz, L. W.; Lamarque, J.-F.; Lin, M.; Prather, M. J.; Young, P. J.; Bergmann, D.; Cameron-Smith, P. J.;
2013-01-01
We have analysed time-slice simulations from 17 global models, participating in the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP), to explore changes in present-day (2000) hydroxyl radical (OH) concentration and methane (CH4) lifetime relative to preindustrial times (1850) and to 1980. A comparison of modeled and observation-derived methane and methyl chloroform lifetimes suggests that the present-day global multi-model mean OH concentration is overestimated by 5 to 10% but is within the range of uncertainties. The models consistently simulate higher OH concentrations in the Northern Hemisphere (NH) compared with the Southern Hemisphere (SH) for the present-day (2000; inter-hemispheric ratios of 1.13 to 1.42), in contrast to observation-based approaches which generally indicate higher OH in the SH although uncertainties are large. Evaluation of simulated carbon monoxide (CO) concentrations, the primary sink for OH, against ground-based and satellite observations suggests low biases in the NH that may contribute to the high north–south OH asymmetry in the models. The models vary widely in their regional distribution of present-day OH concentrations (up to 34%). Despite large regional changes, the multi-model global mean (mass-weighted) OH concentration changes little over the past 150 yr, due to concurrent increases in factors that enhance OH (humidity, tropospheric ozone, nitrogen oxide (NOx) emissions, and UV radiation due to decreases in stratospheric ozone), compensated by increases in OH sinks (methane abundance, carbon monoxide and non-methane volatile organic carbon (NMVOC) emissions). The large inter-model diversity in the sign and magnitude of preindustrial to present-day OH changes (ranging from a decrease of 12.7% to an increase of 14.6%) indicate that uncertainty remains in our understanding of the long-term trends in OH and methane lifetime. We show that this diversity is largely explained by the different ratio of the change in global mean tropospheric CO and NOx burdens (Delta CO/Delta NOx, approximately represents changes in OH sinks versus changes in OH sources) in the models, pointing to a need for better constraints on natural precursor emissions and on the chemical mechanisms in the current generation of chemistry-climate models. For the 1980 to 2000 period, we find that climate warming and a slight increase in mean OH (3.5 +/- 2.2%) leads to a 4.3 +/- 1.9% decrease in the methane lifetime. Analysing sensitivity simulations performed by 10 models, we find that preindustrial to present-day climate change decreased the methane lifetime by about four months, representing a negative feedback on the climate system. Further, we analysed attribution experiments performed by a subset of models relative to 2000 conditions with only one precursor at a time set to 1860 levels. We find that global mean OH increased by 46.4 +/- 12.2% in response to preindustrial to present-day anthropogenic NOx emission increases, and decreased by 17.3 +/-2.3%, 7.6 +/- 1.5%, and 3.1 +/- 3.0% due to methane burden, and anthropogenic CO, and NMVOC emissions increases, respectively.
PROBA-V, the small saellite for global vegetation monitoring
NASA Astrophysics Data System (ADS)
Deronde, Bart; Benhadj, Iskander; Clarijs, Dennis; Dierckx, Wouter; Dries, Jan; Sterckx, Sindy; van Roey, Tom; Wolters, erwin
2015-04-01
PROBA-V, the small satellite for global vegetation monitoring Bart Deronde, Iskander Benhadj, Dennis Clarijs, Wouter Dierckx, Jan Dries, Sindy Sterck, Tom Van Roey, Erwin Wolters (VITO NV) Exactly one year ago, in December 2013, VITO (Flemish Institute for Technological Research) started up the real time operations of PROBA-V. This miniaturised ESA (European Space Agency) satellite was launched by ESA's Vega rocket from Kourou, French-Guyana on May 7th, 2013. After six months of commissioning the mission was taken into operations. Since mid-December 2013 PROBA-V products are processed on an operational basis and distributed to a worldwide user community. PROVA-V is tasked with a full-scale mission: to map land cover and vegetation growth across the entire planet every two days. It is flying a lighter but fully functional redesign of the 'VEGETATION' imaging instruments previously flown on France's full-sized SPOT-4 and SPOT-5 satellites, which have been observing Earth since 1998. PROBA-V, entirely built by a Belgian consortium, continues this valuable and uninterrupted time series with daily products at 300 m and 1 km resolution. Even 100 m products will become available early 2015, delivering a global coverage every 5 days. The blue, red, near-infrared and mid-infrared wavebands allow PROBA-V to distinguish between different types of land cover/use and plant species, including crops. Vital uses of these data include day-by-day tracking of vegetation development, alerting authorities to crop failures, monitoring inland water resources and tracing the steady spread of deserts and deforestation. As such the data is also highly valuable to study climate change and the global carbon cycle. In this presentation we will discuss the in-flight results, one year after launch, from the User Segment (i.e. the processing facility) point of view. The focus will be on geometric and radiometric accuracy and stability. Furthermore, we will elaborate on the lessons learnt from the operational day-to-day activities. Data acquisition, input data quality, instrument programming, image processing and data distribution are some of the topics that will be highlighted. Finally, the synergy with other European missions like the Copernicus Sentinel 3 satellite will be handled.
NASA Astrophysics Data System (ADS)
Soderstrom, Ken; Alalawi, Ali
KLFromRecordingDays allows measurement of Kullback-Leibler (KL) distances between 2D probability distributions of vocal acoustic features. Greater KL distance measures reflect increased phonological divergence across the vocalizations compared. The software has been used to compare *.wav file recordings made by Sound Analysis Recorder 2011 of songbird vocalizations pre- and post-drug and surgical manipulations. Recordings from individual animals in *.wav format are first organized into subdirectories by recording day and then segmented into individual syllables uttered and acoustic features of these syllables using Sound Analysis Pro 2011 (SAP). KLFromRecordingDays uses syllable acoustic feature data output by SAP to a MySQL table to generate and compare "template" (typically pre-treatment) and "target" (typically post-treatment) probability distributions. These distributions are a series of virtual 2D plots of the duration of each syllable (as x-axis) to each of 13 other acoustic features measured by SAP for that syllable (as y-axes). Differences between "template" and "target" probability distributions for each acoustic feature are determined by calculating KL distance, a measure of divergence of the target 2D distribution pattern from that of the template. KL distances and the mean KL distance across all acoustic features are calculated for each recording day and output to an Excel spreadsheet. Resulting data for individual subjects may then be pooled across treatment groups and graphically summarized and used for statistical comparisons. Because SAP-generated MySQL files are accessed directly, data limits associated with spreadsheet output are avoided, and the totality of vocal output over weeks may be objectively analyzed all at once. The software has been useful for measuring drug effects on songbird vocalizations and assessing recovery from damage to regions of vocal motor cortex. It may be useful in studies employing other species, and as part of speech therapies tracking progress in producing distinct speech sounds in isolation.
Peters, Catherine J; Hill, Nathan; Dattani, Mehul T; Charmandari, Evangelia; Matthews, David R; Hindmarsh, Peter C
2013-03-01
Hydrocortisone therapy is based on a dosing regimen derived from estimates of cortisol secretion, but little is known of how the dose should be distributed throughout the 24 h. We have used deconvolution analysis of 24-h serum cortisol profiles to determine 24-h cortisol secretion and distribution to inform hydrocortisone dosing schedules in young children and older adults. Twenty four hour serum cortisol profiles from 80 adults (41 men, aged 60-74 years) and 29 children (24 boys, aged 5-9 years) were subject to deconvolution analysis using an 80-min half-life to ascertain total cortisol secretion and distribution throughout the 24-h period. Mean daily cortisol secretion was similar between adults (6.3 mg/m(2) body surface area/day, range 5.1-9.3) and children (8.0 mg/m(2) body surface area/day, range 5.3-12.0). Peak serum cortisol concentration was higher in children compared with adults, whereas nadir serum cortisol concentrations were similar. Timing of the peak serum cortisol concentration was similar (07.05-07.25), whereas that of the nadir concentration occurred later in adults (midnight) compared with children (22.48) (P = 0.003). Children had the highest percentage of cortisol secretion between 06.00 and 12.00 (38.4%), whereas in adults this took place between midnight and 06.00 (45.2%). These observations suggest that the daily hydrocortisone replacement dose should be equivalent on average to 6.3 mg/m(2) body surface area/day in adults and 8.0 mg/m(2) body surface area/day in children. Differences in distribution of the total daily dose between older adults and young children need to be taken into account when using a three or four times per day dosing regimen. © 2012 Blackwell Publishing Ltd.
Bursts of Self-Conscious Emotions in the Daily Lives of Emerging Adults
Conroy, David E.; Ram, Nilam; Pincus, Aaron L.; Rebar, Amanda L.
2015-01-01
Self-conscious emotions play a role in regulating daily achievement strivings, social behavior, and health, but little is known about the processes underlying their daily manifestation. Emerging adults (n = 182) completed daily diaries for eight days and multilevel models were estimated to evaluate whether, how much, and why their emotions varied from day-to-day. Within-person variation in authentic pride was normally-distributed across people and days whereas the other emotions were burst-like and characterized by zero-inflated, negative binomial distributions. Perceiving social interactions as generally communal increased the odds of hubristic pride activation and reduced the odds of guilt activation; daily communal behavior reduced guilt intensity. Results illuminated processes through which meaning about the self-in-relation-to-others is constructed during a critical period of development. PMID:25859164
Reflection and refraction of hydromagnetic waves at the magnetopause
NASA Technical Reports Server (NTRS)
Verzariu, P.
1973-01-01
Reflection and transmission coefficients of MHD waves are obtained at a stable, plane interface which separates two compressible, perfectly conducting media in relative motion to each other. The coefficients are evaluated for representative conditions of the quiet-time, near-earth magnetopause. The transmission coefficient averaged over a hemispherical distribution of incident waves is found to be 1-2%. Yet the magnitude of the energy flux deposited into the magnetosphere in a day averaged over a hemispherical distribution of waves having amplitudes of say 2-3 gamma, is estimated to be of the order 10 to the 22-nd power erg. Therefore the energy input of MHD waves must contribute significantly to the energy budget of the magnetosphere. The assumption that the boundary surface is a tangential discontinuity with no curvature limits the present theory to hydromagnetic frequencies higher than about .1 Hz.
NASA Astrophysics Data System (ADS)
Acín, Antonio; Gisin, Nicolas; Scarani, Valerio
2004-01-01
We propose a class of quantum cryptography protocols that are robust against photon-number-splitting attacks (PNS) in a weak coherent-pulse implementation. We give a quite exhaustive analysis of several eavesdropping attacks on these schemes. The honest parties (Alice and Bob) use present-day technology, in particular an attenuated laser as an approximation of a single-photon source. The idea of the protocols is to exploit the nonorthogonality of quantum states to decrease the information accessible to Eve due to the multiphoton pulses produced by the imperfect source. The distance at which the key distribution becomes insecure due to the PNS attack is significantly increased compared to the existing schemes. We also show that strong-pulse implementations, where a strong pulse is included as a reference, allow for key distribution robust against photon-number-splitting attacks.
What are single photons good for?
NASA Astrophysics Data System (ADS)
Sangouard, Nicolas; Zbinden, Hugo
2012-10-01
In a long-held preconception, photons play a central role in present-day quantum technologies. But what are sources producing photons one by one good for precisely? Well, in opposition to what many suggest, we show that single-photon sources are not helpful for point to point quantum key distribution because faint laser pulses do the job comfortably. However, there is no doubt about the usefulness of sources producing single photons for future quantum technologies. In particular, we show how single-photon sources could become the seed of a revolution in the framework of quantum communication, making the security of quantum key distribution device-independent or extending quantum communication over many hundreds of kilometers. Hopefully, these promising applications will provide a guideline for researchers to develop more and more efficient sources, producing narrowband, pure and indistinguishable photons at appropriate wavelengths.