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Sample records for 1000-year return period

  1. Reliability, return periods, and risk under nonstationarity

    NASA Astrophysics Data System (ADS)

    Read, Laura K.; Vogel, Richard M.

    2015-08-01

    Water resources design has widely used the average return period as a concept to inform management and communication of the risk of experiencing an exceedance event within a planning horizon. Even though nonstationarity is often apparent, in practice hydrologic design often mistakenly assumes that the probability of exceedance, p, is constant from year to year which leads to an average return period To equal to 1/p; this expression is far more complex under nonstationarity. Even for stationary processes, the common application of an average return period is problematic: it does not account for planning horizon, is an average value that may not be representative of the time to the next flood, and is generally not applied in other areas of water planning. We combine existing theoretical and empirical results from the literature to provide the first general, comprehensive description of the probabilistic behavior of the return period and reliability under nonstationarity. We show that under nonstationarity, the underlying distribution of the return period exhibits a more complex shape than the exponential distribution under stationary conditions. Using a nonstationary lognormal model, we document the increased complexity and challenges associated with planning for future flood events over a planning horizon. We compare application of the average return period with the more common concept of reliability and recommend replacing the average return period with reliability as a more practical way to communicate event likelihood in both stationary and nonstationary contexts.

  2. One hundred years of return period: Strengths and limitations

    NASA Astrophysics Data System (ADS)

    Volpi, E.; Fiori, A.; Grimaldi, S.; Lombardo, F.; Koutsoyiannis, D.

    2015-10-01

    One hundred years from its original definition by Fuller, the probabilistic concept of return period is widely used in hydrology as well as in other disciplines of geosciences to give an indication on critical event rareness. This concept gains its popularity, especially in engineering practice for design and risk assessment, due to its ease of use and understanding; however, return period relies on some basic assumptions that should be satisfied for a correct application of this statistical tool. Indeed, conventional frequency analysis in hydrology is performed by assuming as necessary conditions that extreme events arise from a stationary distribution and are independent of one another. The main objective of this paper is to investigate the properties of return period when the independence condition is omitted; hence, we explore how the different definitions of return period available in literature affect results of frequency analysis for processes correlated in time. We demonstrate that, for stationary processes, the independence condition is not necessary in order to apply the classical equation of return period (i.e., the inverse of exceedance probability). On the other hand, we show that the time-correlation structure of hydrological processes modifies the shape of the distribution function of which the return period represents the first moment. This implies that, in the context of time-dependent processes, the return period might not represent an exhaustive measure of the probability of failure, and that its blind application could lead to misleading results. To overcome this problem, we introduce the concept of Equivalent Return Period, which controls the probability of failure still preserving the virtue of effectively communicating the event rareness.

  3. An update on multivariate return periods in hydrology

    NASA Astrophysics Data System (ADS)

    Gräler, Benedikt; Petroselli, Andrea; Grimaldi, Salvatore; De Baets, Bernard; Verhoest, Niko

    2016-05-01

    Many hydrological studies are devoted to the identification of events that are expected to occur on average within a certain time span. While this topic is well established in the univariate case, recent advances focus on a multivariate characterization of events based on copulas. Following a previous study, we show how the definition of the survival Kendall return period fits into the set of multivariate return periods.Moreover, we preliminary investigate the ability of the multivariate return period definitions to select maximal events from a time series. Starting from a rich simulated data set, we show how similar the selection of events from a data set is. It can be deduced from the study and theoretically underpinned that the strength of correlation in the sample influences the differences between the selection of maximal events.

  4. Surface Temperature Reconstructions for the Last 1000 Years

    NASA Astrophysics Data System (ADS)

    North, G. R.

    2006-12-01

    This is a presentation of results from a recently released report written by a committee established by the National Research Council and chaired by the speaker. The report was titled the same as the title of this talk. It focused on the methods of reconstructing the large scales of such surface temperature fields, since there has been considerable discussion in the scientific literature, assessments such as the IPCC, the popular press, blogs and even Congressional Hearings. The so-called `hockey stick' curve indicating a gradual cooling from the beginning of the record at about 1000AD to roughly 150 years ago when the curve take a steep upward trend (the so-called global warming). The original publications by Mann, Bradley and Hughes were careful to present and emphasize error margins that have been ignored by many in the controversy. The Committee found that numerous subsequent publications have reported reconstructions that utilized different data and different statistical assumptions. These all fall within the error margins of the original studies. While the committee has some reservations about the period prior to the year 1600AD, it still concludes that it is plausible that surface temperatures averaged over the Northern Hemisphere over the last three decades are plausibly the warmest for any such comparable period in the last 1000 years.

  5. Return periods of global climate fluctuations and the pause

    NASA Astrophysics Data System (ADS)

    Lovejoy, S.

    2014-07-01

    An approach complementary to General Circulation Models (GCMs), using the anthropogenic CO2 radiative forcing as a linear surrogate for all anthropogenic forcings [Lovejoy], was recently developed for quantifying human impacts. Using preindustrial multiproxy series and scaling arguments, the probabilities of natural fluctuations at time lags up to 125 years were determined. The hypothesis that the industrial epoch warming was a giant natural fluctuation was rejected with 99.9% confidence. In this paper, this method is extended to the determination of event return times. Over the period 1880-2013, the largest 32 year event is expected to be 0.47 K, effectively explaining the postwar cooling (amplitude 0.42-0.47 K). Similarly, the "pause" since 1998 (0.28-0.37 K) has a return period of 20-50 years (not so unusual). It is nearly cancelled by the pre-pause warming event (1992-1998, return period 30-40 years); the pause is no more than natural variability.

  6. The 2011 Thailand flood: climate causes and return periods

    NASA Astrophysics Data System (ADS)

    Gale, Emma; Saunders, Mark

    2013-04-01

    Thailand is one of the most developed and wealthiest countries in Southeast Asia. However, its tropical location and the influence of seasonal monsoon rains and local topography make it prone to floods. The Thailand floods in 2011 were especially severe causing estimated losses of US 30 billion (economic) and US 12 billion (insured) (Swiss Re, 2012). This insured loss ranks easily as the highest ever worldwide from a freshwater flood disaster (Swiss Re, 2012). We review the nature, impacts and historical ranking of the 2011 Thailand flood, and then discuss the climate causes for the exceptional rainfall which triggered the flood - annual rainfall in 2011 was the highest in Thailand's 61-year precipitation record (Thai Meteorological Department, 2011). Thai precipitation data from 100 stations for the period 1992-2011, NCEP/NCAR mean sea level pressure (MSLP) data and best-track data from the Joint Typhoon Warning Center for the period 1992-2011 are used in this study. We find that the floods were caused by a combination of a strong Southeast Asian summer monsoon that brought high rainfall across the country between May and October, and by the remnants of four tropical storms that brought high rainfall to northern Thailand between June and October. During the monsoon season the Southern Oscillation was moderately positive and, as a result, likely contributed to the high monsoonal rains. We estimate the return periods for the 2011 Thai rains and compare these to satellite-derived return periods for 2011 Thai river flow. The rainfall return period varies from 8-20 years in the north and south of the country to 1-8 years in the east and centre of Thailand. Satellite-derived river flows at two locations on the Chao Phraya River suggest a return period of 10-20 years. The return period is also estimated using historical flood records (Brakenridge, 2012) which suggest a return period of 5-6 years. A 'consensus' return period for the 2011 Thai flood is estimated to be 10

  7. Extreme Volcanic Eruptions: return periods, impact and implications (Invited)

    NASA Astrophysics Data System (ADS)

    Sparks, R. S.

    2010-12-01

    In the very short history of civilisation, a few thousand years, there have been comparably few very large volcanic events which global effects. Such events include very large lavas flow eruptions, such as Laki (Iceland) in 1783 and major caldera-forming explosive eruptions, such as Tambora in 1815 and Tianchi around 930 AD. Much larger magnitude eruptions have happened regularly when time scales of millions of years are considered. The modern globalised world is arguably uniquely vulnerable to very large volcanic events, making the study of their return periods, possible environmental effects and consequences a key goal of volcanology. A database of Quaternary large magnitude explosive eruptions (M ≥ 4) is under development as part of the VOGRIPA project on global volcanic hazards and risk. The database, currently consisting of 1929 entries from 481 Quaternary volcanoes, can be applied to constraining the magnitude-frequency relationship of global and regional explosive volcanism. Application of extreme value statistics to a Holocene subset of data, corrected for under-recording, enables construction of a magnitude-frequency relationship for global volcanism. Return periods based on maximum likelihood statistical analysis are 7.9 years for M ≥ 4, 35 years for M ≥ 5, and 370 years for M ≥ 7.0 with uncertainty increasing with magnitude. The return periods depend on the threshold chosen between the main part of the distribution and the extreme value tail and the results cited here are for a threshold of M = 4. For the largest magnitude eruptions (M > 7.5) the Holocene period is too short to obtain a meaningful result. The effects if an eruption like Tambora 1815 (M ~ 6.9) in the modern world is likely to be dramatic as the populations in SE Asia are now well over 20 time greater and the socio-economic vulnerability has also increased. Effects will include atmospheric pollution lasting a few years, major global climate perturbations and regional disruption

  8. 26 CFR 1.443-1 - Returns for periods of less than 12 months.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 6 2014-04-01 2014-04-01 false Returns for periods of less than 12 months. 1.443-1 Section 1.443-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Accounting Periods § 1.443-1 Returns for periods of less than 12 months. (a) Returns for...

  9. Evaluating the long-term hydrology of an evapotranspiration-capillary barrier with a 1000 year design life

    NASA Astrophysics Data System (ADS)

    Zhang, Z. Fred

    2016-06-01

    A surface barrier is a commonly used technology for isolation of subsurface contaminants. Surface barriers for isolating radioactive waste are expected to perform for centuries to millennia, yet there are very few data for field-scale surface barriers for periods approaching a decade or longer. The Prototype Hanford Barrier (PHB) with a design life of 1000 years was constructed over an existing radioactive waste site in 1994 to demonstrate its long-term performance. The primary element of the PHB is an evapotranspiration-capillary (ETC) barrier in which precipitation water is stored in a fine-textured soil layer and later released to the atmosphere via evapotranspiration. To address the barrier performance under extreme conditions, this study included an enhanced precipitation stress test from 1995 to 1997 to determine barrier response to extreme precipitation events. During this period a 1000 year 24 h return rainstorm was simulated in March every year. The loss of vegetation on barrier hydrology was tested with a controlled fire test in 2008. The 19 year monitoring record shows that the store-and-release mechanism worked as well as or better than the design criterion. Average drainage from the ETC barrier amounted to an average of 0.005 mm yr-1, which is well below the design criterion of 0.5 mm yr-1. After a simulated wildfire, the naturally reestablished vegetation and increased evaporation combined to release the stored water and summer precipitation to the atmosphere such that drainage did not occur in the 5 years subsequent to the fire.

  10. Assessing the potential impacts of climate change on return periods of hydrological extremes in the Illinois River watershed of the Midwestern United States

    NASA Astrophysics Data System (ADS)

    Chien, H.; Yeh, P. J. F.; Knouft, J.

    2014-12-01

    As the Earth's climate is predicted to change significantly in terms of warmer temperature and higher precipitation extremes during this century due to the increased combustion of fossil fuels, accurate estimations of the frequencies of future hydrological extremes are important to understanding the potential impacts of changes in climate on water resources management, particularly in accessing flood risk. The goal of this study is to use the Soil and Water Assessment Tool (SWAT), a distributed landscape-scale hydrological model, to predict current streamflow and the potential impacts of climate change on future stream flows in the Illinois River watershed in the Midwestern United States. Subsequently Gumbel distribution (Extreme Value Type Ⅰ) is fitted to the annual maxima simulated streamflow to derive a number of return periods of future hydrological extremes. The question in this study is: How do the return periods of future hydrological extremes change under future climate change scenarios and what factors cause the change? Daily simulated future streamflow from 2046-2065 and 2081-2100 are simulated using SWAT model based on nine separate downscaled global climate models (GCM) with three emissions scenarios. SWAT model predictions generally indicate that annual streamflow will likely decrease due to warmer temperatures. Based on the simulated daily streamflow, probability models for annual maxima flows frequency analysis are developed using Gumbel distribution and the values of hydrological extremes for different return periods including 50, 100, 200, 500, 1000 years are derived. The change of return periods of hydrological extremes and the implications will be discussed.

  11. A tsunami about 1000 years ago in Puget Sound, Washington

    USGS Publications Warehouse

    Atwater, B.F.; Moore, A.L.

    1992-01-01

    Water surged from Puget Sound sometime between 1000 and 1100 years ago, overrunning tidal marshes and mantling them with centimeters of sand. One overrun site is 10 kilometers northwest of downtown Seattle; another is on Whidbey Island, some 30 kilometers farther north. Neither site has been widely mantled with sand at any other time in the past 2000 years. Deposition of the sand coincided - to the year or less - with abrupt, probably tectonic subsidence at the Seattle site and with landsliding into nearby Lake Washington. These findings show that a tsunami was generated in Puget Sound, and they tend to confirm that a large shallow earthquake occurred in the Seattle area about 1000 years ago.

  12. A Tsunami about 1000 Years Ago in Puget Sound, Washington

    NASA Astrophysics Data System (ADS)

    Atwater, Brian F.; Moore, Andrew L.

    1992-12-01

    Water surged from Puget Sound sometime between 1000 and 1100 years ago, overrunning tidal marshes and mantling them with centimeters of sand. One overrun site is 10 kilometers northwest of downtown Seattle; another is on Whidbey Island, some 30 kilometers farther north. Neither site has been widely mantled with sand at any other time in the past 2000 years. Deposition of the sand coincided-to the year or less-with abrupt, probably tectonic subsidence at the Seattle site and with landsliding into nearby Lake Washington. These findings show that a tsunami was generated in Puget Sound, and they tend to confirm that a large shallow earthquake occurred in the Seattle area about 1000 years ago.

  13. A tsunami about 1000 years ago in puget sound, washington.

    PubMed

    Atwater, B F; Moore, A L

    1992-12-01

    Water surged from Puget Sound sometime between 1000 and 1100 years ago, overrunning tidal marshes and mantling them with centimeters of sand. One overrun site is 10 kilometers northwest of downtown Seattle; another is on Whidbey Island, some 30 kilometers farther north. Neither site has been widely mantled with sand at any other time in the past 2000 years. Deposition of the sand coincided-to the year or less-with abrupt, probably tectonic subsidence at the Seattle site and with landsliding into nearby Lake Washington. These findings show that a tsunami was generated in Puget Sound, and they tend to confirm that a large shallow earthquake occurred in the Seattle area about 1000 years ago. PMID:17742526

  14. Return periods of losses associated with European windstorm series in a changing climate

    NASA Astrophysics Data System (ADS)

    Karremann, Melanie K.; Pinto, Joaquim G.; Reyers, Mark; Klawa, Matthias

    2015-04-01

    During the last decades, several windstorm series hit Europe leading to large aggregated losses. Such storm series are examples of serial clustering of extreme cyclones, presenting a considerable risk for the insurance industry. Clustering of events and return periods of storm series affecting Europe are quantified based on potential losses using empirical models. Moreover, possible future changes of clustering and return periods of European storm series with high potential losses are quantified. Historical storm series are identified using 40 winters of NCEP reanalysis data (1973/1974 - 2012/2013). Time series of top events (1, 2 or 5 year return levels) are used to assess return periods of storm series both empirically and theoretically. Return periods of historical storm series are estimated based on the Poisson and the negative binomial distributions. Additionally, 800 winters of ECHAM5/MPI-OM1 general circulation model simulations for present (SRES scenario 20C: years 1960- 2000) and future (SRES scenario A1B: years 2060- 2100) climate conditions are investigated. Clustering is identified for most countries in Europe, and estimated return periods are similar for reanalysis and present day simulations. Future changes of return periods are estimated for fixed return levels and fixed loss index thresholds. For the former, shorter return periods are found for Western Europe, but changes are small and spatially heterogeneous. For the latter, which combines the effects of clustering and event ranking shifts, shorter return periods are found everywhere except for Mediterranean countries. These changes are generally not statistically significant between recent and future climate. However, the return periods for the fixed loss index approach are mostly beyond the range of preindustrial natural climate variability. This is not true for fixed return levels. The quantification of losses associated with storm series permits a more adequate windstorm risk assessment in a

  15. Stochastic long term modelling of a drainage system with estimation of return period uncertainty.

    PubMed

    Thorndahl, S

    2009-01-01

    Long term prediction of maximum water levels and combined sewer overflow (CSO) in drainage systems are associated with large uncertainties. Especially on rainfall inputs, parameters, and assessment of return periods. This paper proposes a Monte Carlo based methodology for stochastic prediction of both maximum water levels as well as CSO volumes based on operations of the urban drainage model MOUSE in a single catchment case study. Results show quite a wide confidence interval of the model predictions especially on the large return periods. Traditionally, return periods of drainage system predictions are based on ranking, but this paper proposes a new methodology for the assessment of return periods. Based on statistics of characteristic rainfall parameters and correlation with drainage system predictions, it is possible to predict return periods more reliably, and with smaller confidence bands compared to the traditional methodology. PMID:19542638

  16. Eastern Tropical Pacific Mean State and Variability During the Past 1000 Years

    NASA Astrophysics Data System (ADS)

    Rustic, G. T.; Koutavas, A.; Marchitto, T. M., Jr.; Linsley, B. K.

    2014-12-01

    Dynamical changes in the tropical Pacific are hypothesized to have exerted an important influence on climate of the past millennium. However, direct proxy evidence in support of this hypothesis from the Eastern Tropical Pacific remains sparse. Here we present a unique 1000+ year continuous record of oceanic mixed layer temperature and its variability from a sediment multi-core collected in 2009 near the Galápagos Islands. The study location sits in the center of action of the El Niño Southern Oscillation (ENSO), a major driver of tropical and global climate variability. We analyzed Mg/Ca ratios of multiple specimens of the mixed-layer dwelling foraminifera Globigerinoides ruber to reconstruct mean sea surface temperature (SST) over the past 1000 years. We also analyzed δ18O from individual specimens of G. ruber from the same samples to assess mixed layer temperature variability during the same period. Both the multi-shell Mg/Ca and single-shell δ18O reveal statistically significant and systematic changes during the past millennium. The Medieval Climate Anomaly (MCA, ~1100-1400 CE) features a sustained period of ~1°C cooler mean surface temperatures and reduced variability (by up to 35%) compared to the late 20th century. Little Ice Age (LIA) mean mixed layer temperatures were comparatively warmer and much more variable than the MCA. Intervals with greater variability than modern, as well as intervals with lower than modern variability are both present in the LIA. The most recent sediment interval corresponding to the period 1985-2009 CE has the highest mean SST of the past 1000 years, although it is within error of temperatures from ~1000 CE. An estimate of the zonal SST gradient of the tropical Pacific based on this Mg/Ca data and similar data from the western Pacific supports a pattern of enhanced zonal gradient during the MCA and reduced gradient during the LIA. We explore the implications of these results for tropical Pacific dynamics in the context of

  17. Intense Southwest Florida hurricane landfalls over the past 1000 years

    NASA Astrophysics Data System (ADS)

    Ercolani, Christian; Muller, Joanne; Collins, Jennifer; Savarese, Michael; Squiccimara, Louis

    2015-10-01

    Recent research has proposed that human-induced sea surface temperature (SST) warming has led to an increase in the intensity of hurricanes over the past 30 years. However, this notion has been challenged on the basis that the instrumental record is too short and unreliable to reveal long-term trends in hurricane activity. This study addresses this limitation by investigating hurricane-induced overwash deposits (paleotempestites) behind a barrier island in Naples, FL, USA. Paleotempestologic proxies including grain size, percent calcium carbonate, and fossil shells species were used to distinguish overwash events in two sediment cores spanning the last one thousand years. Two prominent paleotempestites were observed in the top 20 cm of both cores: the first identified as Hurricane Donna in 1960 whereas an older paleotempestite (1900-1930) could represent one of three documented storms in the early 1900s. An active period of hurricane overwash from 1000 to 500 yrs. BP and an inactive period from 500 to 150 yrs. BP correlate with reconstructed SSTs from the Main Development Region (MDR) of the North Atlantic Ocean. We observe an increased number of paleotempestites when MDR SSTs are warmer, coinciding with the Medieval Warm Period, and very few paleotempestites when MDR SSTs are cooler, coinciding with the Little Ice Age. Results from this initial Southwest Florida study indicate that MDR SSTs have been a key long-term climate driver of intense Southwest Florida hurricane strikes.

  18. Return period adjustment for runoff coefficients based on analysis in undeveloped Texas watersheds

    USGS Publications Warehouse

    Dhakal, Nirajan; Fang, Xing; Asquith, William H.; Cleveland, Theodore G.; Thompson, David B.

    2013-01-01

    The rational method for peak discharge (Qp) estimation was introduced in the 1880s. The runoff coefficient (C) is a key parameter for the rational method that has an implicit meaning of rate proportionality, and the C has been declared a function of the annual return period by various researchers. Rate-based runoff coefficients as a function of the return period, C(T), were determined for 36 undeveloped watersheds in Texas using peak discharge frequency from previously published regional regression equations and rainfall intensity frequency for return periods T of 2, 5, 10, 25, 50, and 100 years. The C(T) values and return period adjustments C(T)/C(T=10  year) determined in this study are most applicable to undeveloped watersheds. The return period adjustments determined for the Texas watersheds in this study and those extracted from prior studies of non-Texas data exceed values from well-known literature such as design manuals and textbooks. Most importantly, the return period adjustments exceed values currently recognized in Texas Department of Transportation design guidance when T>10  years.

  19. Estimation of the return period for Gumbel processes with applications to air quality measures. Technical report No. 36

    SciTech Connect

    Galfond, G

    1980-03-01

    The return period for a pollutant concentration to exceed a given level is often of interest. For example, the return period for exceeding government standards is a useful measure of long term air quality. Or, for medical reasons, one might be interested in the return period for exceeding some significant harm level. The report examines several estimates of the return period based on extreme value theory and illustrates applications to air quality data.

  20. Attribution of Global Precipitation Change over the Past 1000 Years

    NASA Astrophysics Data System (ADS)

    Liu, J.; Wang, B.; Yim, S.

    2010-12-01

    Precipitation is essential to human life and sustainable civilization. Attribution of climate change of global precipitation is far more challenge than attributing temperature change. So far little has been known about the global precipitation change in the past. Using millennial simulations with a coupled climate model (ECHO-G), here we show that the global precipitation over the past millennium exhibits three major modes of variability. The largest portion of variability is associated with an internal mode which fluctuates irregularly and intermittently on multi-decadal time scale. More importantly, two salient forced modes that display distinct dynamic structures and origins are found, which together account for more variances than the internal mode. The first dominates the preanthropogenic change (pre-1850 AD) and is associated with solar-volcanic radiative variations. This natural forced mode shows a bicentennial oscillation superposed on a contrast between Medieval Warm Period (MWP) and Little Ice Age (LIA). The enhanced (suppressed) precipitation during MWP (LIA) is coupled with a La Nina (El Nino) type global warming pattern. The second forced mode closely follows variation of greenhouse gas concentration and concentrates its variance in the industrial era (post-1850 AD). This anthropogenic mode is characterized by enhanced precipitation in western Pacific coupled with a central Pacific warming. The post-1850 trend in precipitation can be faithfully reconstructed by the two forced modes.

  1. A 1000-Year Carbon Isotope Rainfall Proxy Record from South African Baobab Trees (Adansonia digitata L.).

    PubMed

    Woodborne, Stephan; Hall, Grant; Robertson, Iain; Patrut, Adrian; Rouault, Mathieu; Loader, Neil J; Hofmeyr, Michele

    2015-01-01

    A proxy rainfall record for northeastern South Africa based on carbon isotope analysis of four baobab (Adansonia digitata L.) trees shows centennial and decadal scale variability over the last 1,000 years. The record is in good agreement with a 200-year tree ring record from Zimbabwe, and it indicates the existence of a rainfall dipole between the summer and winter rainfall areas of South Africa. The wettest period was c. AD 1075 in the Medieval Warm Period, and the driest periods were c. AD 1635, c. AD 1695 and c. AD1805 during the Little Ice Age. Decadal-scale variability suggests that the rainfall forcing mechanisms are a complex interaction between proximal and distal factors. Periods of higher rainfall are significantly associated with lower sea-surface temperatures in the Agulhas Current core region and a negative Dipole Moment Index in the Indian Ocean. The correlation between rainfall and the El Niño/Southern Oscillation Index is non-static. Wetter conditions are associated with predominantly El Niño conditions over most of the record, but since about AD 1970 this relationship inverted and wet conditions are currently associated with la Nina conditions. The effect of both proximal and distal oceanic influences are insufficient to explain the rainfall regime shift between the Medieval Warm Period and the Little Ice Age, and the evidence suggests that this was the result of a northward shift of the subtropical westerlies rather than a southward shift of the Intertropical Convergence Zone. PMID:25970402

  2. A 1000-Year Carbon Isotope Rainfall Proxy Record from South African Baobab Trees (Adansonia digitata L.)

    PubMed Central

    2015-01-01

    A proxy rainfall record for northeastern South Africa based on carbon isotope analysis of four baobab (Adansonia digitata L.) trees shows centennial and decadal scale variability over the last 1,000 years. The record is in good agreement with a 200-year tree ring record from Zimbabwe, and it indicates the existence of a rainfall dipole between the summer and winter rainfall areas of South Africa. The wettest period was c. AD 1075 in the Medieval Warm Period, and the driest periods were c. AD 1635, c. AD 1695 and c. AD1805 during the Little Ice Age. Decadal-scale variability suggests that the rainfall forcing mechanisms are a complex interaction between proximal and distal factors. Periods of higher rainfall are significantly associated with lower sea-surface temperatures in the Agulhas Current core region and a negative Dipole Moment Index in the Indian Ocean. The correlation between rainfall and the El Niño/Southern Oscillation Index is non-static. Wetter conditions are associated with predominantly El Niño conditions over most of the record, but since about AD 1970 this relationship inverted and wet conditions are currently associated with la Nina conditions. The effect of both proximal and distal oceanic influences are insufficient to explain the rainfall regime shift between the Medieval Warm Period and the Little Ice Age, and the evidence suggests that this was the result of a northward shift of the subtropical westerlies rather than a southward shift of the Intertropical Convergence Zone. PMID:25970402

  3. Development of a wind gust model to estimate gust speeds and their return periods

    NASA Astrophysics Data System (ADS)

    Seregina, Larisa; Haas, Rabea; Born, Kai; Pinto, Joaquim G.

    2014-05-01

    Spatially dense observations of gust speeds are necessary for various applications, but their availability is limited in space and time. This work presents an approach to help to overcome this problem. The main objective is the generation of synthetic wind gust velocities. With this aim, theoretical wind and gust distributions are estimated from ten years of hourly observations collected at 123 synoptic weather stations provided by the German Weather Service. In a first step, an exposure correction is applied on measurements of the mean wind velocity to reduce the influence of local urban and topographic effects. In a second step, a transfer function is built between distribution parameters of wind and gust velocities. The aim of this step is to estimate the parameters of gusts at stations where only wind speed data is available. These parameters can be used in a third step to generate synthetic gusts, which can improve the accuracy of return periods at test sites with a lack of observations. The second objective is to determine return periods much longer than the nominal length of the original time series by considering extreme value statistics. Estimates for both local maximum return periods and average return periods for single historical events are provided. The comparison of maximum and average return periods shows that even storms with short average return periods may lead to local wind gusts with return periods of several decades. Despite uncertainties caused by the short length of the observational records, the method leads to consistent results, enabling a wide range of possible applications.

  4. 26 CFR 1.443-1 - Returns for periods of less than 12 months.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 26 Internal Revenue 6 2013-04-01 2013-04-01 false Returns for periods of less than 12 months. 1.443-1 Section 1.443-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED... period ($18,836×1/12) 1,570 Example 3. The Y Corporation makes a re- turn for the six-month period...

  5. 26 CFR 1.443-1 - Returns for periods of less than 12 months.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 6 2012-04-01 2012-04-01 false Returns for periods of less than 12 months. 1.443-1 Section 1.443-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED... period ($18,836×1/12) 1,570 Example 3. The Y Corporation makes a re- turn for the six-month period...

  6. 26 CFR 1.443-1 - Returns for periods of less than 12 months.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 6 2010-04-01 2010-04-01 false Returns for periods of less than 12 months. 1.443-1 Section 1.443-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED... period ($18,836×1/12) 1,570 Example 3. The Y Corporation makes a re- turn for the six-month period...

  7. 26 CFR 1.443-1 - Returns for periods of less than 12 months.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 6 2011-04-01 2011-04-01 false Returns for periods of less than 12 months. 1.443-1 Section 1.443-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED... period ($18,836×1/12) 1,570 Example 3. The Y Corporation makes a re- turn for the six-month period...

  8. Estimation of return periods of multiple losses per winter associated with historical windstorm series over Germany

    NASA Astrophysics Data System (ADS)

    Karremann, Melanie; Pinto, Joaquim G.; von Bomhard, Philipp; Klawa, Matthias

    2014-05-01

    During the last decades, several windstorm series hit Western Europe leading to large cumulative economic losses. Such storm series are an example of serial clustering of extreme cyclones and present a considerable risk for the insurance industry. Here, clustering of events and return periods of storm series for Germany are quantified based on potential losses using empirical models. Two reanalysis datasets and observations from 123 German Weather Service stations are considered for the winters 1981/1982 to 2010/2011. Based on these datasets, histograms of events exceeding selected return levels (1-, 2- and 5-year) are derived. Return periods of historical storm series are estimated based on the Poisson and the negative Binomial distribution. About 4680 years of global circulation model simulations forced with current climate conditions are analysed to provide a better assessment of historical return periods. Estimations differ between the considered distributions. Except for frequent and weak events, the return period estimates obtained with the Poisson distribution clearly deviate from empirical data. This clearly documents overdispersion in the loss data, thus indicating the clustering of potential loss events. Better assessments are achieved for the negative Binomial distribution, e.g. 34 to 53 years for the storm series like 1989/1990. The overdispersion (clustering) of potential loss events clearly states the importance of an adequate risk assessment of multiple events per winter for economical applications.

  9. Severe wind gust thresholds for Meteoalarm derived from uniform return periods in ECA&D

    NASA Astrophysics Data System (ADS)

    Stepek, A.; Wijnant, I. L.; van der Schrier, G.; van den Besselaar, E. J. M.; Klein Tank, A. M. G.

    2012-06-01

    In this study we present an alternative wind gust warning guideline for Meteoalarm, the severe weather warning website for Europe. There are unrealistically large differences in levels and issuing frequencies of all warning levels currently in use between neighbouring Meteoalarm countries. This study provides a guide for the Meteoalarm community to review their wind gust warning thresholds. A more uniform warning system is achieved by using one pan-European return period per warning level. The associated return values will be different throughout Europe because they depend on local climate conditions, but they will not change abruptly at country borders as is currently the case for the thresholds. As return values are a measure of the possible danger of an event and its impact on society, they form an ideal basis for a warning system. Validated wind gust measurements from the European Climate Assessment and Dataset (ECA&D, http://www.ecad.eu) were used to calculate return values of the annual maximum wind gust. The current thresholds are compared with return values for 3 different return periods: 10 times a year return periods for yellow warnings, 2 yr periods for orange and 5 yr periods for red warnings. So far 10 countries provide wind gust data to ECA&D. Due to the ECA&D completeness requirements and the fact that some countries provided too few stations to be representative for that country, medians of the return values of annual maximum wind gust could be calculated for 6 of the 10 countries. Alternative guideline thresholds are presented for Norway, Ireland, The Netherlands, Germany, the Czech Republic and Spain and the need to distinguish between coastal, inland and mountainous regions is demonstrated. The new thresholds based on uniform return periods differ significantly from the current ones, particularly for coastal and mountainous areas. We are aware of other, sometimes binding factors (e.g. laws) that

  10. The return period analysis of natural disasters with statistical modeling of bivariate joint probability distribution.

    PubMed

    Li, Ning; Liu, Xueqin; Xie, Wei; Wu, Jidong; Zhang, Peng

    2013-01-01

    New features of natural disasters have been observed over the last several years. The factors that influence the disasters' formation mechanisms, regularity of occurrence and main characteristics have been revealed to be more complicated and diverse in nature than previously thought. As the uncertainty involved increases, the variables need to be examined further. This article discusses the importance and the shortage of multivariate analysis of natural disasters and presents a method to estimate the joint probability of the return periods and perform a risk analysis. Severe dust storms from 1990 to 2008 in Inner Mongolia were used as a case study to test this new methodology, as they are normal and recurring climatic phenomena on Earth. Based on the 79 investigated events and according to the dust storm definition with bivariate, the joint probability distribution of severe dust storms was established using the observed data of maximum wind speed and duration. The joint return periods of severe dust storms were calculated, and the relevant risk was analyzed according to the joint probability. The copula function is able to simulate severe dust storm disasters accurately. The joint return periods generated are closer to those observed in reality than the univariate return periods and thus have more value in severe dust storm disaster mitigation, strategy making, program design, and improvement of risk management. This research may prove useful in risk-based decision making. The exploration of multivariate analysis methods can also lay the foundation for further applications in natural disaster risk analysis. PMID:22616629

  11. 7 CFR 273.32 - Households who return to TANF during the transitional period.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 4 2012-01-01 2012-01-01 false Households who return to TANF during the transitional period. 273.32 Section 273.32 Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE FOOD STAMP AND FOOD DISTRIBUTION...

  12. 7 CFR 273.32 - Households who return to TANF during the transitional period.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 4 2011-01-01 2011-01-01 false Households who return to TANF during the transitional period. 273.32 Section 273.32 Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE FOOD STAMP AND FOOD DISTRIBUTION...

  13. 7 CFR 273.32 - Households who return to TANF during the transitional period.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 4 2013-01-01 2013-01-01 false Households who return to TANF during the transitional period. 273.32 Section 273.32 Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE FOOD STAMP AND FOOD DISTRIBUTION...

  14. 7 CFR 273.32 - Households who return to TANF during the transitional period.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 4 2014-01-01 2014-01-01 false Households who return to TANF during the transitional period. 273.32 Section 273.32 Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE FOOD STAMP AND FOOD DISTRIBUTION...

  15. Determining the Return Period of Storm Surge Events in the Philippines

    NASA Astrophysics Data System (ADS)

    Santiago, Joy; Suarez, John Kenneth; Lapidez, John Phillip; Mendoza, Jerico; Caro, Carl Vincent; Tablazon, Judd; Ladiero, Christine; Mahar Francisco Lagmay, Alfredo

    2015-04-01

    The devastating damages generated by the Tropical Cyclone Haiyan storm surges in Eastern Samar, Philippines prompted the Department of Science and Technology-Project NOAH (Nationwide Operational Assessment of Hazards) to calculate the return period and storm surge exceedance probability of these events. The recurrence interval or the period of return of a storm surge event is the estimated likelihood that that event would occur again. Return periods are measured through historical data denoting the interval of recurrence in average over a period of time. The exceedance probability however, is a graphical representation that describes the probability that some various levels of loss will be exceeded over a future time period or will be surpassed over a given time. DOST-Project NOAH simulates storm surge height time series using JMA storm surge model which is a numerical model based on shallow water equations. To determine the period of recurrence of storm surges with this type of intensity, the agency intends to compute the estimation of storm surge heights generated by tropical cyclones for 2-year, 5-year, 10-year, 25-year, 50-year and 100-year return periods for the Philippine coast. The storm surge time series generated from JMA combined with WXTide simulation, a software containing archives/catalogues of world-wide astronomical tides, and 5-meter resolution DEM were used as input parameters for the inundation model, which shows probable extent of flooding at a specific storm surge return period. Flo-2D two-dimensional flood routing model, a GIS integrated software tool that facilitates the creation of the flood model grid system, was used for flood hazard model. It is a simple volume conservation model composed of processor program that facilitate graphical editing and mapping of flooding details which uses continuity equation and the dynamic wave momentum equations. The measurements of storm surge return period and probable extent of coastal flooding in the

  16. Reconstruction and analysis of spring rainfall over the southeastern US for the past 1000 years

    SciTech Connect

    Stahle, D.W.; Cleaveland, M.K. )

    1992-12-01

    Tree-ring chronologies can provide surprisingly accurate estimates of the natural variability of important climate parameters such as precipitation and temperature during the centuries prior to the industrial Revolution. Bald cypress tree-ring chronologies have been used to reconstruct spring rainfall for the past 1000 years in North Carolina, South Carolina, and Georgia. These rainfall reconstructions explain from 54% to 68% of the spring rainfall variance in each state, and are well verified against independent rainfall measurements. In fact, these tree-ring data explain only 6% to 13% less statewide rainfall variance than is explained by the same number of instrumental raingage records. The reconstructions indicate that the spring rainfall extremes and decade-long regimes witnessed during the past century of instrumental observation have been a prominent feature of southeastern United States climate over the past millennium. These spring rainfall regimes are linked in part to anomalies in the seasonal expansion and migration of the subtropical anticyclone over the North Atlantic. The western sector of the Bermuda high often ridges strongly westward into the southeastern United States during dry springs, but during wet springs it is usually located east of its mean position and well offshore. Similar anomalies in the western sector of the Bermuda high occurred during multidecadal regimes of spring rainfall over the Southeast. During the relatively dry springs from 1901 to 1939, the high often ridged into the Southeast, but the western periphery of the high was more frequently located offshore during the relatively wet period from 1940 to 1980. Spring and summer rainfall extremes and decade-long regimes over the Southeast are frequently out of phase, and the tendency for wet (dry) springs to be followed by dry (wet) summers also appears to reflect anomalies in the zonal position of the Bermuda high during spring and summer.

  17. From Mush to Eruption in 1000 Years: Rapid Assembly of the Super-Sized Oruanui Magma Body

    NASA Astrophysics Data System (ADS)

    Allan, A. S.; Morgan, D. J.; Wilson, C. J.; Millet, M.

    2012-12-01

    The mush model is useful in explaining how large volumes of evolved silicic melt can be generated in and extracted from a crystal-rich source to form crystal-poor rhyolite magma bodies at shallow crustal levels. It is unclear, however, how processes of melt extraction and/or formation of the melt-dominant magma body might be reflected in the crystal record, and what physical and temporal constraints can be applied. Textural observations and in situ geochemical fingerprints in crystals from pumices of the ~25.4 ka Oruanui eruption (Taupo, New Zealand), offer new perspectives on the processes, physical conditions and timing of the melt extraction and accumulation. Almost all orthopyroxene (opx) and plagioclase (plag) cores have textures showing a period of disequilibrium (partial dissolution and/or resorption) followed by stable conditions (infilling of raddled cores; euhedral rim overgrowths). Trace element contents in amphibole (amph), which was stable and actively crystallizing in all but the most evolved parcels of Oruanui magma, complement textural evidence showing that Mn and Zn liberated by opx dissolution were preferentially sequestered in amph. Concentrations of these opx-loving elements show a prominent inflection when plotted against indices of melt evolution (e.g. Eu/Eu* in amph) marking a return to opx stability and subsequent crystallization. Plagioclase, the most abundant crystal phase, records a more complex history with significant inheritance, but textural and chemical evidence suggests that at least some of Oruanui plag crystals experienced the same departure from and return to stability as the opx. Amphibole trace element data are linked to in situ estimates of P-T-fO2 and melt H2O determined via the Ridolfi et al. (2010: Contrib Mineral Petrol 160, 45) thermobarometer. Textural and geochemical evidence combined with P-T-H2O model values indicate that three major Oruanui crystal phases (opx, amph, plag) record a significant decompression event

  18. Challenges estimating the return period of extreme floods for reinsurance applications

    NASA Astrophysics Data System (ADS)

    Raven, Emma; Busby, Kathryn; Liu, Ye

    2013-04-01

    Mapping and modelling extreme natural events is fundamental within the insurance and reinsurance industry for assessing risk. For example, insurers might use a 1 in 100-year flood hazard map to set the annual premium of a property, whilst a reinsurer might assess the national scale loss associated with the 1 in 200-year return period for capital and regulatory requirements. Using examples from a range of international flood projects, we focus on exploring how to define what the n-year flood looks like for predictive uses in re/insurance applications, whilst considering challenges posed by short historical flow records and the spatial and temporal complexities of flood. First, we shall explore the use of extreme value theory (EVT) statistics for extrapolating data beyond the range of observations in a marginal analysis. In particular, we discuss how to estimate the return period of historical flood events and explore the impact that a range of statistical decisions have on these estimates. Decisions include: (1) selecting which distribution type to apply (e.g. generalised Pareto distribution (GPD) vs. generalised extreme value distribution (GEV)); (2) if former, the choice of the threshold above which the GPD is fitted to the data; and (3) the necessity to perform a cluster analysis to group flow peaks to temporally represent individual flood events. Second, we summarise a specialised multivariate extreme value model, which combines the marginal analysis above with dependence modelling to generate industry standard event sets containing thousands of simulated, equi-probable floods across a region/country. These events represent the typical range of anticipated flooding across a region and can be used to estimate the largest or most widespread events that are expected to occur. Finally, we summarise how a reinsurance catastrophe model combines the event set with detailed flood hazard maps to estimate the financial cost of floods; both the full event set and also

  19. [Experimental study of the root supply system with periodic water return designed for space greenhouses].

    PubMed

    Berkovich, Iu A; Smolianina, S O; Krivobok, N M

    2000-01-01

    To improve reliability of plant's moistening and aeration control in microgravity, an original root supply system with a periodic return water flow has been designed and tested in laboratory. For 30 days crops of Pekinese cabbage (Brassica pekinesis (Lour Rupr), Khibini sort) were raised in the test bench which allowed adjustment of water potential in the root zone within a preset range. A three-step water potential control algorithm included water injection with a pump-dispenser, a pause, and water sucking back to a desired value of water potential. The following parameters of the control cycle were selected in a series of two experiments: time of water injection (2.5 hr) and return (1.5 hr), and a pause of 8 and 20 hr, respectively. Magnitude of water potential about the root module axis was controlled in the range from -1.3 kPa to -3.0 kPa in both experiments and maintained at -1.3 kPa in the control. The root modules consisted of porous metaloceramic tubes wrapped in fibrous ion exchanging cloth and a light-proof film with planting slots on top. In the first experiment, plant characteristics were comparable to the control. The developed procedure and technology can be used to provide favourable moisture-air conditions in the root zone. By and large, the system of root nutrition with a periodic water return has demonstrated high capacity during the ground-based cultivation of plants. To use this system in space greenhouse, it is necessary to specify operational parameters for the microgravity environment. PMID:10826063

  20. A fast version of LASG/IAP climate system model and its 1000-year control integration

    NASA Astrophysics Data System (ADS)

    Zhou, Tianjun; Wu, Bo; Wen, Xinyu; Li, Lijuan; Wang, Bin

    2008-07-01

    A fast version of the State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG)/Institute of Atmospheric Physics (IAP) climate system model is briefly documented. The fast coupled model employs a low resolution version of the atmospheric component Grid Atmospheric Model of IAP/LASG (GAMIL), with the other parts of the model, namely an oceanic component LASG/IAP Climate Ocean Model (LICOM), land component Common Land Model (CLM), and sea ice component from National Center for Atmospheric Research Community Climate System Model (NCAR CCSM2), as the same as in the standard version of LASG/IAP Flexible Global Ocean Atmosphere Land System model (FGOALS g). The parameterizations of physical and dynamical processes of the atmospheric component in the fast version are identical to the standard version, although some parameter values are different. However, by virtue of reduced horizontal resolution and increased time-step of the most time-consuming atmospheric component, it runs faster by a factor of 3 and can serve as a useful tool for longterm and large-ensemble integrations. A 1000-year control simulation of the present-day climate has been completed without flux adjustments. The final 600 years of this simulation has virtually no trends in global mean sea surface temperatures and is recommended for internal variability studies. Several aspects of the control simulation’s mean climate and variability are evaluated against the observational or reanalysis data. The strengths and weaknesses of the control simulation are evaluated. The mean atmospheric circulation is well simulated, except in high latitudes. The Asian-Australian monsoonal meridional cell shows realistic features, however, an artificial rainfall center is located to the eastern periphery of the Tibetan Plateau persists throughout the year. The mean bias of SST resembles that of the standard version, appearing as a “double ITCZ” (Inter-Tropical Convergence

  1. Temperature variability of the last 1000 years in Antarctica from inert gas isotopes

    NASA Astrophysics Data System (ADS)

    Orsi, Anais; Landais, Amaelle; Severinghaus, Jeffrey P.

    2015-04-01

    A large effort has been made to document the climate history of the last two thousand years, but there are still substantial gaps in the Southern Hemisphere, especially at high latitudes, where the changes in the climate are the largest. These gaps limit our understanding of the most fundamental driving mechanisms of the climate. In particular, the impact of solar minima on surface temperature is not fully understood. Here, we investigate the spatial structure of multi decadal climate variability in Antarctica, assess the significance of the Little Ice Age minimum documented elsewhere. We present a 1000 year temperature record at two sites in Antarctica: WAIS Divide (79°S, 112°W, 1766 m a.s.l), and Talos Dome (72°S, 159°E, 2315 m a.s.l), reconstructed from the combination of inert gas isotopes from the ice core and borehole temperature measurements. Borehole temperature provides an absolute estimate of long-term trends, while noble gases track decadal to centennial scale changes. This method provides a temperature reconstruction that is independent of water isotopes, and allows us to improve our understanding of water isotopes as a temperature proxy, and use them to track circulation changes. We find that there is a pronounced cooling trend over the last millennium at both sites, but it is stronger in East Antarctica (Talos Dome) than West Antarctica (WAIS-D). At WAIS Divide, we find that "Little Ice Age" cold period of 1400-1800 was 0.52°C colder than the last century, and that the recent warming trend (0.23°C/decade since 1960) has past analogs about every 200 years. At Talos Dome, the pronounced cooling trend over the whole record is not visible in the water isotope record, which suggests that there is a compensation of several sources of fractionation. Overall, both records are consistent with the idea that the solar minima and persistent volcanic activity of the Little Ice Age (1400-1850 A.D.) had a significant impact on the surface temperature in

  2. Levee reliability analyses for various flood return periods - a case study in southern Taiwan

    NASA Astrophysics Data System (ADS)

    Huang, W.-C.; Yu, H.-W.; Weng, M.-C.

    2015-04-01

    In recent years, heavy rainfall conditions have caused disasters around the world. To prevent losses by floods, levees have often been constructed in inundation-prone areas. This study performed reliability analyses for the Chiuliao First Levee in southern Taiwan. The failure-related parameters were the water level, the scouring depth, and the in situ friction angle. Three major failure mechanisms were considered: the slope sliding failure of the levee and the sliding and overturning failures of the retaining wall. When the variability of the in situ friction angle and the scouring depth are considered for various flood return periods, the variations of the factor of safety for the different failure mechanisms show that the retaining wall sliding and overturning failures are more sensitive to the change of the friction angle. When the flood return period is greater than 2 years, the levee could fail with slope sliding for all values of the water level difference. The results of levee stability analysis considering the variability of different parameters could aid engineers in designing the levee cross sections, especially with potential failure mechanisms in mind.

  3. Levee reliability analyses for various flood return periods - a case study in Southern Taiwan

    NASA Astrophysics Data System (ADS)

    Huang, W.-C.; Yu, H.-W.; Weng, M.-C.

    2015-01-01

    In recent years, heavy rainfall conditions have caused damages around the world. To prevent damages by floods, levees have often been constructed in prone-to-inundation areas. This study performed reliability analyses for the Chiuliao 1st Levee located in southern Taiwan. The failure-related parameters were the water level, the scouring depth, and the in-situ friction angle. Three major failure mechanisms were considered, including the slope sliding failure of the levee, and the sliding and overturning failures of the retaining wall. When the variabilities of the in-situ friction angle and the scouring depth are considered for various flood return periods, the variations of the factor of safety (FS) for the different failure mechanisms show that the retaining wall sliding and overturning failures are more sensitive to the variability of the friction angle. When the flood return period is greater than 2 years, the levee can undergo slope sliding failure for all values of the water level difference. The results for levee stability analysis considering the variability of different parameters could assist engineers in designing the levee cross sections, especially with potential failure mechanisms in mind.

  4. First Annually Resolved Marine Temperature Series For The Last 1000 Years From The North Atlantic

    NASA Astrophysics Data System (ADS)

    Reynolds, D.; Scourse, J. D.; Richardson, C.; Hall, I. R.; Butler, P.; Nederbragt, A.; Wanamaker, A. D.; Becker, J.

    2013-12-01

    There remain very few high-resolution records of marine climate variability covering the last 1000 years; annually-resolved series have hitherto been confined to coral archives from the low latitude oceans and do not cover the full millennium. We have constructed a 1357-year crossdated sclerochronology based on annual growth increments in the long-lived bivalve mollusc Arctica islandica, collected by dredge from the temperate North Atlantic (Grimsey, North Icelandic shelf, 80 m water depth; Butler et al. 2013). We present here annual- to sub-annually-resolved oxygen isotope data from the last 1000 years of this absolute chronology. Radiocarbon analysis of the series demonstrates variability in the marine reservoir effect (ΔR) controlled by Atlantic vs. Arctic water masses (Irminger Current, East Icelandic Current) with enhanced ingress of Irminger Current water during the Medieval Climate Anomaly and since AD 1900; the Little Ice Age is conversely characterized by Arctic water masses (Wanamaker et al. 2012). We use the ΔR variability to correct for the isotopic content of seawater (δ18Ow) and hence convert δ18Oshell to seawater temperature at 80m, a calibration supported by comparison with instrumental series. This reveals the evolution of North Atlantic seawater temperatures over the last 1000 years in unprecedented detail and provides a basis for the comparison of marine with terrestrial series at the same resolution for the first time.

  5. 26 CFR 1.6038-1 - Information returns required of domestic corporations with respect to annual accounting periods...

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... corporations with respect to annual accounting periods of certain foreign corporations beginning before January... Information returns required of domestic corporations with respect to annual accounting periods of certain... paragraph (c) of this section, for each annual accounting period (described in paragraph (d) of this...

  6. Blast from the Past: Pervasive Impact and Landscape-Scale Modification from Historical Mining Over 1000 Years in Central Sweden

    NASA Astrophysics Data System (ADS)

    Hansson, S.; Bindler, R.

    2011-12-01

    In the public consciousness Sweden is often viewed as a largely natural landscape. However, many parts of the landscape have undergone substantial changes. For example, in the historically and culturally important Bergslagen region in central Sweden, which played an important role in the economic development of Sweden since the medieval period, agriculture and mining have greatly transformed the landscape over the past 1000 years. Bergslagen is an ore-rich region characterized as a granite-porphyr belt formed 1900 Ma ago, with thousands of mines and mine pits, hundreds of furnaces, smelters and forges distributed throughout the area. Drawing on data from selected lake sediment records from different historical mining districts in Central Sweden (e.g. Norberg mining district - iron ores and Falun mining district - copper ores) the aim of this presentation is to show how small-scale but pervasively widespread mining and metallurgy, along with associated settlement, have transformed the surrounding landscape. These anthropogenic activities led to changes in sedimentation and erosion rates, forest structure, and also causing large-scale metal pollution and ecological changes in recipient watercourses and lakes. This historical pollution was oftentimes on a scale we associate with modern mining pollution. Our research is based on analyses of lake sediment records, which include multi-element analyses of minor and trace elements using XRF, mercury, carbon, and in some lakes also pollen and diatoms. In two lakes in Norberg, recent catastrophic failure (1991) of a sand magazine below a now closed mine led to significant contamination of the two downstream lakes, with Cu and Hg concentrations up to 1800 ppm and 1400 ppb, respectively. These concentrations are 50 and 20 times greater than natural background values. However, such elevated concentrations are also frequently found in sediments dated to the 16th-18th centuries. For example, in one lake in the Norberg iron mining

  7. Estimating return periods for daily precipitation extreme events over the Brazilian Amazon

    NASA Astrophysics Data System (ADS)

    Santos, Eliane Barbosa; Lucio, Paulo Sérgio; Santos e Silva, Cláudio Moisés

    2015-08-01

    This paper aims to model the occurrence of daily precipitation extreme events and to estimate the return period of these events through the extreme value theory (generalized extreme value distribution (GEV) and the generalized Pareto distribution (GPD)). The GEV and GPD were applied in precipitation series of homogeneous regions of the Brazilian Amazon. The GEV and GPD goodness of fit were evaluated by quantile-quantile (Q-Q) plot and by the application of the Kolmogorov-Smirnov (KS) test, which compares the cumulated empirical distributions with the theoretical ones. The Q-Q plot suggests that the probability distributions of the studied series are appropriated, and these results were confirmed by the KS test, which demonstrates that the tested distributions have a good fit in all sub-regions of Amazon, thus adequate to study the daily precipitation extreme event. For all return levels studied, more intense precipitation extremes is expected to occur within the South sub-regions and the coastal area of the Brazilian Amazon. The results possibly will have some practical application in local extreme weather forecast.

  8. The mental health of children upon their return home after a long displacement period.

    PubMed

    Grgić, Mirela; Vidović, Vesna; Butković-Soldo, Silva; Vuksić-Mihaljević, Zeljka; Degmecić, Dunja; Laufer, Davor

    2005-12-01

    The aim of this study was to determine the different levels of depression, hopelessness and post-traumatic stress disorder between two groups of adolescents, those who returned to Baranja and those from Osijek. The first group consisted of 57 adolescents (32 female and 25 male) with the mean age of 17.36, who were grammar school students in Beli Manastir (Gimnazija, Beli Manastir). The mean duration of displacement period was 7 years. The second group consisted of 58 adolescents of grammar school students in Osijek (III. gimnazija, Osijek) (32 female and 26 male) with the mean age of 17.28. All examinees filled in the Croatian version of the Children's Depression Inventory (CDI), the Hopelessness Scale for Children (HSC) and Children's Post-Traumatic Stress Disorder (PTSD) Inventory. The analysis of the results did not show any statistically significant difference between these two groups regarding levels of depression, hopelessness and post-traumatic stress disorder. The results point out rather good psychosocial adjustment of adolescents upon their return home after 4 years. PMID:16417158

  9. Development of a wind-gust model to estimate gust values and their return periods

    NASA Astrophysics Data System (ADS)

    Seregina, Larisa; Haas, Rabea; Born, Kai; Pinto, Joaquim G.

    2013-04-01

    Spatially dense observations of gust speeds are necessary for the validation of climate models, but the observations are limited in space and time. The use of country specific thresholds for gust reports additionally reduces the availability of gust observations. This work presents an approach to help overcome problem. The first objective of this approach is the generation of synthetic gust velocities out of distribution parameters of wind velocities. With this aim, theoretical wind and gust distributions are estimated from ten years of hourly observations made at 123 synoptic weather stations provided by the German weather service (DWD). The approach consists of three steps. In the first step, an exposure correction is applied on the measurements of the mean wind velocity to reduce the influence of local urban and topographic effects. The second step consists of linear regressions applied on the parameters of the theoretical distribution of wind and gust velocities. The regression parameters gained by this procedure are used in the third step to set a transfer function to estimate distribution parameters of the gust velocity, which are applied afterwards to estimate gust velocities. The estimated distribution parameters are validated by the use of the so-called leave-one-out method. The estimated gusts can improve the accuracy of return periods at test sites with a lack of observations. The consideration of extreme value statistics enables to obtain return periods much longer that the nominal length of the original time series. Despite of uncertainties caused by the short length of the observational records, the method leads to satisfying results.

  10. Forest response to 1,000 years of drought variability in the Southwestern United States

    NASA Astrophysics Data System (ADS)

    Williams, A. P.; Meko, D. M.; Woodhouse, C. A.; Cook, E.; Swetnam, T. W.; Macalady, A. K.; Allen, C. D.; Rauscher, S. A.; Jiang, X.; Grissino-Mayer, H.; McDowell, N. G.; Cai, M.

    2011-12-01

    Droughts in the early 1950s and early 2000s significantly accelerated tree mortality rates in the Southwestern United States. During the early 2000s, forest inventory data indicate that the proportion of dead piñon pine, ponderosa pine, and Douglas-fir trees doubled in the Southwest. The 2000s drought peaked in 2002 and was the most severe drought in at least 100 years. In 2011, precipitation, dew-point, and wind data indicate the intensity of the 2002 drought has been surpassed in a number of ways. Measurements of water potential in piñon pine trees in northern New Mexico indicate that, at present, trees have less access to soil moisture than in 2002 when widespread mortality occurred. How do these recent droughts compare to those of the last 1000 years? We used records of annual tree-ring widths from 309 populations of piñon pine, ponderosa pine, and Douglas-fir throughout the Southwestern United States to reconstruct a single record of regional drought stress from 1000-2005 AD. This record indicates that the last Southwestern drought similar in intensity to one in the early 2000s occurred in the late 1600s. Both of these droughts, however, paled in comparison to a mega-drought that occurred from 1575-1595. The emergence from this mega-drought, around 1600 AD, appears to mark a transition period from a time when droughts similar the early 2000s drought were much more common. Tree-age studies indicate a scarcity of Southwestern trees with rings extending back beyond the mega-drought of the late 1500s. This suggests that (1) the late-1500s mega-drought triggered a massive die-off of forests and/or (2) the higher frequency of drought events prior to the mega-drought sustained a much more sparse forest population than the one that has thrived from the 1600s through present. Given this apparent plasticity of Southwestern forests, a change in the forest population should be underway if higher temperatures contribute to forest drought stress. The Southwestern tree

  11. Examining Insurance Loss Return Periods with Extreme Event Intensity Thresholds across the US: 1980-2010

    NASA Astrophysics Data System (ADS)

    Smith, A. B.

    2010-12-01

    To improve the “effectiveness” of NOAA storm event information for risk managers, planners, policy makers and public safety, NOAA’s NCDC is integrating U.S. hazards/exposure data with respective insurance loss return periods. This is performed by calculating county-level extreme event intensity thresholds using these data types: hurricanes (NHC), winter storms (NESIS/RESIS), tornadoes (SPC; SWDI), hail (SPC; SWDI), high winds (SPC), drought (USDM/NIDIS), and U.S. insurance loss datasets (Munich Re, USDA-RMA, PCS, FEMA). This research also utilizes NWS warning data, socioeconomic data from the Bureau of Economic Analysis (BEA), and U.S. Census data (e.g., gridded population/density, mean housing value, per capita income, production wealth) to normalize for increases in population, inflation, and wealth. This work seeks to establish county-level U.S. extreme event economic risk climatologies for the period 1980-2010. This research will inform a new derived risk data product to improve information on extreme event loss frequencies and clustering across time and space horizons. Acronyms: FEMA: Federal Emergency Management Administration NESIS: Northeast Snowfall Impact Scale NHC: (NOAA) National Hurricane Center NIDIS: National Integrated Drought Information System PCS: Property Claim Services RESIS: Regional Snowfall Impact Scale SPC: (NOAA) Storm Prediction Center SWDI: (NOAA) Severe Weather Data Inventory USDA-RMA: U.S. Department of Agriculture - Risk Management Agency USDM: U.S. Drought Monitor

  12. Evaluation of the Precision of Return Period calculated by GSMaP data

    NASA Astrophysics Data System (ADS)

    Taguchi, R.; Seto, S.

    2015-12-01

    A heavy rain by Typhoon1326 was generated over IzuOshima Island on October 17, 2013. As for nine rain gauges in IzuOshima Island, precipitation amount exceeded the threshold of the special warning for 3 hours. However, the special warning was not announced because it did not satisfy "heavy rainfall over the threshold value is recorded at more than 10 points". It is suggested that the special warning at islands is hard to be announced. Therefore we propose to apply GSMaP which can be used not only over land but over ocean for the special warning. We calculated the threshold of the special warning by using GSMaP data and compared it with that by Japan Meteorological Agency (JMA). GSMaP has the following characteristics. ・GSMaP estimates precipitation every hour with the resolution of 0.1 degrees grid. ・GSMaP is not good at orographic rainfall , but it is good at rainfall over the Tropics and ocean. ・GSMaP covers almost all over the world between 60 degrees north and south. The standard of JMA is as follows. ・The amount of rainfall in 3 hours exceed 50-year value at 10 points in the spread of the prefecture degree. ・The amount of rainfall in 48 hours exceed 50-year value at 50 points in the spread of the prefecture degree. We calculated the amount of 50-year rainfall by GSMaP and compared it with the threshold value of JMA. But there are only 9-year GSMaP data used in this study. The number of sample is too little to calculate return period. We have also added the data at the surrounding grids. We tried to increase the number of samples in this way. GSMaP has several problems. One of that's GSMaP mistakes snow for rainfall. So we grasped the characteristics of such case. And we made the mask to take such case. When we calculate with the mask, the abnormal values has decreased. We improved stability of calculation return period with these ways.

  13. Estimating return periods of extreme values from relatively short time series of winds

    NASA Astrophysics Data System (ADS)

    Jonasson, Kristjan; Agustsson, Halfdan; Rognvaldsson, Olafur; Arfeuille, Gilles

    2013-04-01

    An important factor for determining the prospect of individual wind farm sites is the frequency of extreme winds at hub height. Here, extreme winds are defined as the value of the highest 10 minutes averaged wind speed with a 50 year return period, i.e. annual exceeding probability of 2% (Rodrigo, 2010). A frequently applied method to estimate winds in the lowest few hundred meters above ground is to extrapolate observed 10-meter winds logarithmically to higher altitudes. Recent study by Drechsel et al. (2012) showed however that this methodology is not as accurate as interpolating simulated results from the global ECMWF numerical weather prediction (NWP) model to the desired height. Observations of persistent low level jets near Colima in SW-Mexico also show that the logarithmic approach can give highly inaccurate results for some regions (Arfeuille et al., 2012). To address these shortcomings of limited, and/or poorly representative, observations and extrapolations of winds one can use NWP models to dynamically scale down relatively coarse resolution atmospheric analysis. In the case of limited computing resources one has typically to make a compromise between spatial resolution and the duration of the simulated period, both of which can limit the quality of the wind farm siting. A common method to estimate maximum winds is to fit an extreme value distribution (e.g. Gumbel, gev or Pareto) to the maximum values of each year of available data, or the tail of these values. If data are only available for a short period, e.g. 10 or 15 years, then this will give a rather inaccurate estimate. It is possible to deal with this problem by utilizing monthly or weekly maxima, but this introduces new problems: seasonal variation, autocorrelation of neighboring values, and increased discrepancy between data and fitted distribution. We introduce a new method to estimate return periods of extreme values of winds at hub height from relatively short time series of winds, simulated

  14. Ensemble approach for projections of return periods of extreme water levels in Estonian waters

    NASA Astrophysics Data System (ADS)

    Eelsalu, Maris; Soomere, Tarmo; Pindsoo, Katri; Lagemaa, Priidik

    2014-12-01

    The contribution of various drivers to the water level in the eastern Baltic Sea and the presence of outliers in the time series of observed and hindcast water level lead to large spreading of projections of future extreme water levels. We explore the options for using an ensemble of projections to more reliably evaluate return periods of extreme water levels. An example of such an ensemble is constructed by means of fitting several sets of block maxima (annual maxima and stormy season maxima) with a Generalised Extreme Value, Gumbel and Weibull distribution. The ensemble involves projections based on two data sets (resolution of 6 h and 1 h) hindcast by the Rossby Centre Ocean model (RCO; Swedish Meteorological and Hydrological Institute) and observed data from four representative sites along the Estonian coast. The observed data are transferred into the grid cells of the RCO model using the HIROMB model and a linear regression. For coastal segments where the observations represent the offshore water level well, the overall appearance of the ensembles signals that the errors of single projections are randomly distributed and that the median of the ensemble provides a sensible projection. For locations where the observed water level involves local effects (e.g. wave set-up) the block maxima are split into clearly separated populations. The resulting ensemble consists of two distinct clusters, the difference between which can be interpreted as a measure of the impact of local features on the water level observations.

  15. A revised atmospheric δ13C-CO2 record covering the last 1000 years from Law Dome, Antarctica

    NASA Astrophysics Data System (ADS)

    Rubino, M.; Etheridge, D. M.; Trudinger, C. M.; Allison, C.; Battle, M. O.; Bender, M. L.; Langenfelds, R.; Steele, P.; Curran, M.; Blunier, T.; Jenk, T. M.; Francey, R.

    2012-12-01

    We present a revised and expanded record of atmospheric δ13C-CO2 extracted from ice cores sampled at Law Dome (East Antarctica) and firn air sampled at Law Dome and at South Pole covering the last 1000 years. We have performed new measurements of 13C of CO2 extracted from ice, incorporated the results from new firn sampling campaigns in Antarctica and merged them with a revised version of the previous δ13C-CO2 measurements [Francey et al., 1999]. Our new measurements from Law Dome ice increase the temporal sampling density over the last 200 years and show good agreement with the results from South Pole firn, providing evidence that our new record reliably extend the Cape Grim δ13C-CO2 record back in time. We also show the preliminary measurements aimed at covering the preindustrial period with higher sample density, including the 10 ppm CO2 decrease observed in ice from Law Dome at the beginning of 1600 AD [Etheridge et al., 1996, MacFarling Meure et al., 2006]. Having higher sample density for both CO2 and δ13C-CO2 in that period allows us to infer sources and sinks of CO2 with higher confidence. Corresponding author: Mauro Rubino, mauro.rubino@csiro.au, +61(0)392394634 References Etheridge, D. et al. (1996), ISSN: 01480227. MacFarling Meure, C. et al. (2006), DOI: 10.1029/2006GL026152. Francey, R. J. et al. (1999), ISSN: 02806509.

  16. 26 CFR 1.6038-2 - Information returns required of United States persons with respect to annual accounting periods...

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 13 2014-04-01 2014-04-01 false Information returns required of United States persons with respect to annual accounting periods of certain foreign corporations beginning after December 31, 1962. 1.6038-2 Section 1.6038-2 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX...

  17. 26 CFR 1.6038-1 - Information returns required of domestic corporations with respect to annual accounting periods...

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 13 2014-04-01 2014-04-01 false Information returns required of domestic corporations with respect to annual accounting periods of certain foreign corporations beginning before January 1, 1963. 1.6038-1 Section 1.6038-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX...

  18. Rainfall erosivity and rainfall return period in the experimental watershed of Aracruz, in the Coastal Plain of Espirito Santo, Brazil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The knowledge of the factors influencing water erosion is relevant to land management practices. Rainfall, expressed by rainfall erosivity, is very important among the factors affecting water erosion. Thus, the objective of this study was to determine rainfall erosivity and return period for the Coa...

  19. The joint return period analysis of natural disasters based on monitoring and statistical modeling of multidimensional hazard factors.

    PubMed

    Liu, Xueqin; Li, Ning; Yuan, Shuai; Xu, Ning; Shi, Wenqin; Chen, Weibin

    2015-12-15

    As a random event, a natural disaster has the complex occurrence mechanism. The comprehensive analysis of multiple hazard factors is important in disaster risk assessment. In order to improve the accuracy of risk analysis and forecasting, the formation mechanism of a disaster should be considered in the analysis and calculation of multi-factors. Based on the consideration of the importance and deficiencies of multivariate analysis of dust storm disasters, 91 severe dust storm disasters in Inner Mongolia from 1990 to 2013 were selected as study cases in the paper. Main hazard factors from 500-hPa atmospheric circulation system, near-surface meteorological system, and underlying surface conditions were selected to simulate and calculate the multidimensional joint return periods. After comparing the simulation results with actual dust storm events in 54years, we found that the two-dimensional Frank Copula function showed the better fitting results at the lower tail of hazard factors and that three-dimensional Frank Copula function displayed the better fitting results at the middle and upper tails of hazard factors. However, for dust storm disasters with the short return period, three-dimensional joint return period simulation shows no obvious advantage. If the return period is longer than 10years, it shows significant advantages in extreme value fitting. Therefore, we suggest the multivariate analysis method may be adopted in forecasting and risk analysis of serious disasters with the longer return period, such as earthquake and tsunami. Furthermore, the exploration of this method laid the foundation for the prediction and warning of other nature disasters. PMID:26327640

  20. Joint return periods in hydrology: a critical and practical review focusing on the synthetic design hydrograph estimation

    NASA Astrophysics Data System (ADS)

    Vandenberghe, S.; Graeler, B.; van den Berg, M. J.; Grimaldi, S.; Petroselli, A.; De Baets, B.; Verhoest, N. E. C.

    2012-04-01

    In several branches of engineering the selection of design variables is a common exercise. Recently, there is increasing interest in considering several variables at the same time in the design, which are likely to be associated with each other. In hydrology and hydraulics, applications such as the design of sewer systems or dams, the calculation of flood risks, etc. require the selection of characteristic variables of rainfall or discharge events with a predefined return period. So far, well-established univariate frequency analysis methods have been a standard tool in practice. In contrast, newer methods show a tendency of describing hydrological phenomena with multiple variables. This is challenging practitioners to calculate the multivariate return period and to select a specific design event. In literature, several approaches for the latter problem have evolved over the years, however no study exists on how these methods compare to each other and a controversy on which approach is the right one is going on. In this study, an overview will first be given on the state of the art for defining joint return periods. The construction of multivariate distribution functions will focus on copulas, given their practicality in multivariate frequency analysis. Subsequently, a case study focusing on the selection of design hydrograph characteristics is introduced. In this application, design values of a 3-dimensional phenomenon composed of peak discharge, volume and duration are derived (for given return periods). This case study investigates and compares the different definitions of joint return periods and allows to highlight important issues with respect to multivariate frequency analysis.

  1. Fresh-water cementation of a 1,000-year-old oolite

    USGS Publications Warehouse

    Halley, R. B.; Harris, P. M.

    1979-01-01

    Calcite cementation of aragonite ooid sand is producing oolite on Joulters Cays, Bahamas. During the last 1,000 years, calcite cement has formed at an average rate of between 27 and 55 cm3 /m3 /yr and is derived from dissolution of ooid aragonite in fresh water. The dissolution-reprecipitation of carbonate minerals in the aquifer results in ground waters of unusually high Sr content. Sea water and mixtures of fresh and sea water appear to inhibit cementation. A pronounced cement fabric change occurs across the water table and has produced an obvious petrographic record of fresh-water diagenesis. Above the water table, cement is typically near grain contact positions, where water is held by capillarity; below the water table, cement is more randomly distributed around grains. At the water table a transition zone, 1 meter thick, marks the boundary between cement textures. No porosity reduction is associated with cementation; calcite cement precipitation is apparently compensated by an equal or greater amount of aragonite dissolution in the interval undergoing cementation. Permeability is more variable above the water table than below it, reflecting early channelling of flow patterns in the vadose zone. Effective permeability below the water table is one to two orders of magnitude higher than above the water table because of entrained gas in the vadose zone. This permeability difference promotes preservation of unstable minerals above the water table and continued diagenetic alteration below the water table.

  2. Teleconnections and internal variability of the Asian Monsoon in the last 1000 years from paleoclimate data

    NASA Astrophysics Data System (ADS)

    Rehfeld, Kira; Goswami, Bedartha; Marwan, Norbert; Breitenbach, Sebastian; Lechleitner, Franziska; Molkenthin, Nora; Kurths, Jürgen

    2013-04-01

    The Asian monsoon is a climate phenomenon with global reach, impacting on 60% of the world's population, and extremes in its dynamics affect both the people and the economies of Asia. Investigating past climate changes in the Asian monsoon system offers a unique key to understanding its future behavior under anthropogenic perturbation, because our global past is the only truthful realization of the "Earth System experiment" we can access. Paleoclimate data are hereby the only witnesses that testify directly about the state of the Earth system in the past. However, in order to be able to infer on the climatic processes reflected in the proxy data, three inherent challenges need to be met: the datasets are heterogeneously sampled in time (i), space (ii) and time itself is a variable that needs to be reconstructed, which (iii) introduces additional uncertainties. Addressing these issues using adapted similarity estimators, flexible network measures and numerical simulation, we infer spatio-temporal dependencies from paleoclimate networks. We then investigate, to what extent the decadal-scale variability recorded in the paleoclimate data from trees, speleothems, sediments and ice cores is due to internal variability of the Indian and the East Asian monsoon systems, and how potential teleconnections with the El Niño southern oscillation, the North Atlantic oscillation, and solar variability have varied over the last 1000 years.

  3. The Recognition of Multi-Decadal Scale Climate Variability in the Paleo-record over the Past 1000 Years

    NASA Astrophysics Data System (ADS)

    Swart, Peter; Waite, Amanda; Rosenheim, Brad; Moses, Chris

    2010-05-01

    Proxy reconstructions of climate from tree rings, corals, stalagmites, sclerosponges, and deep-sea sediments show multi-decadal climate variability preserved in records extending back at least 1000 years. Most of these records appear to show a strong correlation with indices such as the North Atlantic Oscillation (NAO) and the Atlantic Multi-decadal Oscillation (AMO) over the period of the instrumental record (~1850-present). The repeated recognition of these signals in a number of different archives and geographical locations throughout the Atlantic (Cape Verde Islands, Gulf of Guinea, Puerto Rico, Cariaco Basin , South Florida, and the Bahamas) strongly suggests that these signals are real and have climatic significance. The AMO and NAO climate signals are manifested in these indices through (i) the direct effect of water temperature and salinity on the growth rate of trees and corals and (ii) temperature and salinity influences on the incorporation of geochemical proxies, such as the Mg/Ca, Sr/Ca, and oxygen isotopic ratios, into the skeletons of different carbonate producing organisms. In many areas these relationships are complex and there is often considerable local variability in the response of corals and trees, particularly in the growth rate related parameters. Prior to the instrumental period, the tree-ring index compiled by (Gray et al., 2004, GRL,31) has been taken as the principal reconstruction of the AMO. While most of the marine records examined appear to correlate with the tree-ring record during the instrumental period, there are significant discrepancies prior to 1850. This raises many questions about the stationarity and persistence of the AMO and the suitability of individual archives such as tree rings for these modes.

  4. Effect of initial conditions and of intra-event rainfall intensity variability on shallow landslide triggering return period

    NASA Astrophysics Data System (ADS)

    Peres, David Johnny; Cancelliere, Antonino

    2016-04-01

    Assessment of shallow landslide hazard is important for appropriate planning of mitigation measures. Generally, return period of slope instability is assumed as a quantitative metric to map landslide triggering hazard on a catchment. The most commonly applied approach to estimate such return period consists in coupling a physically-based landslide triggering model (hydrological and slope stability) with rainfall intensity-duration-frequency (IDF) curves. Among the drawbacks of such an approach, the following assumptions may be mentioned: (1) prefixed initial conditions, with no regard to their probability of occurrence, and (2) constant intensity-hyetographs. In our work we propose the use of a Monte Carlo simulation approach in order to investigate the effects of the two above mentioned assumptions. The approach is based on coupling a physically based hydrological and slope stability model with a stochastic rainfall time series generator. By this methodology a long series of synthetic rainfall data can be generated and given as input to a landslide triggering physically based model, in order to compute the return period of landslide triggering as the mean inter-arrival time of a factor of safety less than one. In particular, we couple the Neyman-Scott rectangular pulses model for hourly rainfall generation and the TRIGRS v.2 unsaturated model for the computation of transient response to individual rainfall events. Initial conditions are computed by a water table recession model that links initial conditions at a given event to the final response at the preceding event, thus taking into account variable inter-arrival time between storms. One-thousand years of synthetic hourly rainfall are generated to estimate return periods up to 100 years. Applications are first carried out to map landslide triggering hazard in the Loco catchment, located in highly landslide-prone area of the Peloritani Mountains, Sicily, Italy. Then a set of additional simulations are performed

  5. It's T time: A study on the return period of multivariate problems

    NASA Astrophysics Data System (ADS)

    Michailidi, Eleni Maria; Balistrocchi, Matteo; Bacchi, Baldassare

    2016-04-01

    One of the most important tasks a hydrologist must face is the proper estimation of the 'design values' of a natural variable corresponding to a given Return Period, T, of failures of the hydraulic 'structure' to be designed or verified. Sometimes the 'structure' is simply the embankments, the failure of which corresponds to the outflows of flood runoff on the surrounding land. The widely adopted definition of T, in a problem regarding the maxima of hydrological variables, is "the average time elapsing between two successive occurrences of an event exceeding a certain magnitude of the natural variables". If T is referred to the minima, the symmetric definition pertains to the "average time between two periods during which the variable ranges below a given magnitude". Conventional (and the only accepted) approaches for estimation of T involve a single natural variable (i.e. flood-peak of a river at a given cross section, the daily maximum discharge, the maximum daily rainfall depth observed at a given rain-gauge). The method of estimation of T entails a frequency analysis of the variable of interest, where the design value of a given T is needed to design the structure of interest (e.g. dams, sewers). In other words, T is used as the index value to set the assigned risk level for the hydraulic works. However, a univariate approach in complex problems ignores the effect of significant variables interrelation leading to different risk levels for each quantity of interest and resulting in a completely wrong estimate of the risk. For example, if one considers the flood inflow in a lake around which cities and villages are positioned, the variable to be investigated in relation to the risk assessment is the lake water level. It is obvious that the same water level may occur from very different flood hydrographs, even when the same initial water level and the same rate curve of outflows are considered. This is a consequence of the interaction of at least three joint

  6. Terrigenous material supply to the Peruvian central continental shelf (Pisco, 14° S) during the last 1000 years: paleoclimatic implications

    NASA Astrophysics Data System (ADS)

    Briceño-Zuluaga, Francisco Javier; Sifeddine, Abdelfettah; Caquineau, Sandrine; Cardich, Jorge; Salvatteci, Renato; Gutierrez, Dimitri; Ortlieb, Luc; Velazco, Federico; Boucher, Hugues; Machado, Carine

    2016-03-01

    In the eastern Pacific, lithogenic input to the ocean responds to variations in the atmospheric and oceanic system and their teleconnections over different timescales. Atmospheric (e.g., wind fields), hydrological (e.g., fresh water plumes) and oceanic (e.g., currents) conditions determine the transport mode and the amount of lithogenic material transported from the continent to the continental shelf. Here, we present the grain size distribution of a composite record of two laminated sediment cores retrieved from the Peruvian continental shelf that record the last ˜ 1000 years at a sub-decadal to centennial time-series resolution. We propose novel grain size indicators of wind intensity and fluvial input that allow reconstructing the oceanic-atmospheric variability modulated by sub-decadal to centennial changes in climatic conditions. Four grain size modes were identified. Two are linked to aeolian inputs (M3: ˜ 54; M4: ˜ 91 µm on average), the third is interpreted as a marker of sediment discharge (M2: ˜ 10 µm on average), and the last is without an associated origin (M1: ˜ 3 µm). The coarsest components (M3 and M4) dominated during the Medieval Climate Anomaly (MCA) and the Current Warm Period (CWP) periods, suggesting that aeolian transport increased as a consequence of surface wind stress intensification. In contrast, M2 displays an opposite behavior, exhibiting an increase in fluvial terrigenous input during the Little Ice Age (LIA) in response to more humid conditions associated with El Niño-like conditions. Comparison with other South American paleoclimate records indicates that the observed changes are driven by interactions between meridional displacement of the Intertropical Convergence Zone (ITCZ), the South Pacific Subtropical High (SPSH) and Walker circulation at decadal and centennial timescales.

  7. The return periods and risk assessment of severe dust storms in Inner Mongolia with consideration of the main contributing factors.

    PubMed

    Liu, Xueqin; Li, Ning; Xie, Wei; Wu, Jidong; Zhang, Peng; Ji, Zhonghui

    2012-09-01

    This study presents a methodology for return period analysis and risk assessment of severe dust storm disaster. Meteorological observation data, soil moisture data, and remote sensing data from 30 meteorological stations in Inner Mongolia (western China) from 1985 to 2006 were used for the study. A composite index of severe dust storm disaster (Index I (SDS)) based on the influence mechanisms of the main contributing factors was developed by using the analytic hierarchy process and the weighted comprehensive method, and the hazard risk curves (i.e., the transcendental probability curves of I (SDS)) for the 30 stations were established using the parameter estimation method. We then analyzed the risk of the occurrence of severe dust storm under different scenarios of 5-, 10-, 20-, and 50-year return periods. The results show that the risk decreased from west to east across Inner Mongolia, and there are four severe dust storm occurrence peak value centers, including Guaizihu, Jilantai, Hailisu, and Zhurihe-Erenhot. The severity of dust storms in seven places will be intolerable in the 50-year return period scenario and in three places in the 20-year return period scenario. These results indicate that these locations should concentrate forces on disaster prevention, monitoring, and early warning. The I (SDS) was developed as an easily understandable tool useful for the assessment and comparison of the relative risk of severe dust storm disasters in different areas. The risk assessment was specifically intended to support local and national government agencies in their management of severe dust storm disasters in their efforts to (1) make resource allocation decisions, (2) make high-level planning decisions, and (3) raise public awareness of severe dust storm risk. PMID:21956339

  8. Expressions of climate perturbations in western Ugandan crater lake sediment records during the last 1000 years

    NASA Astrophysics Data System (ADS)

    Mills, K.; Ryves, D. B.; Anderson, N. J.; Bryant, C. L.; Tyler, J. J.

    2014-08-01

    Equatorial East Africa has a complex regional patchwork of climate regimes, sensitive to climate fluctuations over a variety of temporal and spatial scales during the late Holocene. Understanding how these changes are recorded in and interpreted from biological and geochemical proxies in lake sedimentary records remains a key challenge to answering fundamental questions regarding the nature, spatial extent and synchroneity of climatic changes seen in East African palaeo-records. Using a paired lake approach, where neighbouring lakes share the same geology, climate and landscape, it might be expected that the systems will respond similarly to external climate forcing. Sediment cores from two crater lakes in western Uganda spanning the last ~1000 years were examined to assess diatom community responses to late Holocene climate and environmental changes, and to test responses to multiple drivers using redundancy analysis (RDA). These archives provide annual to sub-decadal records of environmental change. Lakes Nyamogusingiri and Kyasanduka appear to operate as independent systems in their recording of a similar hydrological response signal via distinct diatom records. However, whilst their fossil diatom records demonstrate an individualistic, indirect response to external (e.g. climatic) drivers, the inferred lake levels show similar overall trends and reflect the broader patterns observed in Uganda and across East Africa. The lakes appear to be sensitive to large-scale climatic perturbations, with evidence of a dry Medieval Climate Anomaly (MCA; ca. AD 1000-1200). The diatom record from Lake Nyamogusingiri suggests a drying climate during the main phase of the Little Ice Age (LIA) (ca. AD 1600-1800), whereas the diatom response from the shallower Lake Kyasanduka is more complex (with groundwater likely playing a key role), and may be driven more by changes in silica and other nutrients, rather than by lake level. The sensitivity of these two Ugandan lakes to regional

  9. Reconstruction and Analysis of Spring Rainfall over the Southeastern U.S. for the Past 1000 Years.

    NASA Astrophysics Data System (ADS)

    Stahle, David W.; Cleaveland, Malcolm K.

    1992-12-01

    Tree-ring chronologies can provide surprisingly accurate estimates of the natural variability of important climate parameters such as precipitation and temperature during the centuries prior to the Industrial Revolution. Bald cypress tree-ring chronologies have been used to reconstruct spring rainfall for the past 1000 years in North Carolina, South Carolina, and Georgia. These rainfall reconstructions explain from 54% to 68% of the spring rainfall variance in each state, and are well verified against independent rainfall measurements. In fact, these tree-ring data explain only 6% to 13% less statewide rainfall variance than is explained by the same number of instrumental raingage records. The reconstructions indicate that the spring rainfall extremes and decade-long regimes witnessed during the past century of instrumental observation have been a prominent feature of southeastern United States climate over the past millennium. These spring rainfall regimes are linked in part to anomalies in the seasonal expansion and migration of the subtropical anticyclone over the North Atlantic. The western sector of the Bermuda high often ridges strongly westward into the southeastern United States during dry springs, but during wet springs it is usually located east of its mean position and well offshore. Similar anomalies in the western sector of the Bermuda high occurred during multidecadal regimes of spring rainfall over the Southeast. During the relatively dry springs from 1901 to 1939, the high often ridged into the Southeast, but the western periphery of the high was more frequently located offshore during the relatively wet period from 1940 to 1980. Spring and summer rainfall extremes and decade-long regimes over the Southeast are frequently out of phase, and the tendency for wet (dry) springs to be followed by dry (wet) summers also appears to reflect anomalies in the zonal position of the Bermuda high during spring and summer.

  10. 1000 Years of the Olympic Games: Treasures of Ancient Greece--Digital Reconstruction at the Home of the Gods.

    ERIC Educational Resources Information Center

    Kenderdine, Sarah

    This paper results from a recently completed project that augmented an exhibition at the Powerhouse Museum, Sydney, entitled "1000 Years of the Olympic Games: Treasures of Ancient Greece" (July 18-November 18, 2000). This Exhibition offered an opportunity to supplement the traditional visitor experience with the introduction of "virtual reality"…

  11. Timing of magma storage at the Vulcano Island during the last 1000 years

    NASA Astrophysics Data System (ADS)

    De Rosa, Rosanna; Donato, Paola; Gioncada, Anna; Giuffrida, Marisa; Nicotra, Eugenio; Viccaro, Marco

    2016-04-01

    Understanding the nature and timescales of magmatic processes is one of the primary goals of modern volcanology, and chemical zoning is an efficient tool to achieve this aim. In basic volcanic rocks, plagioclase is a common phase used for documenting magmatic processes and their timescales. This is chiefly due to its stability over a wide range of physical-chemical conditions and its sensitivity to changes in thermodynamic parameters during its growth in magma storage and transport zones. We present here textural analysis and major (SEM-EDS/WDS) and trace (LA-ICP-MS) element zoning data on plagioclase crystals from selected volcanic products of Vulcano (Aeolian Islands), emitted during the last 1000 years. The collected samples belong to the La Fossa cone (Palizzi latitic lava flow, latitic enclaves within Commenda and Pietre Cotte rhyolitic lava flows, 1888-90 spatter bombs) and Vulcanello peninsula (shoshonitic and shoshonitic-latitic lava flows at the end of Vulcanello I and Vulcanello 3 phases, respectively). Textural observations through polarizing optical microscope, high-contrast BSE images and SEM-EDS/WDS core-to-rim profiles, allowed to discriminate four different plagioclase textures, namely: 1) oscillatory-zoned crystals; 2) sieve-textured rims; 3) dissolved/resorbed cores; 4) cores with coarse sieve-textures. Plagioclase with sieve-textured rims and coarsely-sieved cores (Types 2 and 4) are the most abundant in the analyzed products. The estimates of maximum magma residence time have been obtained on crystals with exclusive oscillatory-zoned patterns (Type 1) or portions of crystals not severely affected by μm-sized glass inclusions caused by disequilibrium. We used one-step modeling of Sr diffusion considering the highest An content of each crystal and magma temperature ranging between 1075 and 1175° C. Textural observations and core-to-rim profiles on plagioclases show that dynamics of magma ascent and storage are markedly different at La Fossa and

  12. Climate and ocean variability during the past 1000 years in Pescadero basin, southern Gulf of California, Mexico.

    NASA Astrophysics Data System (ADS)

    Tenorio, Alejandra; Pérez-Cruz, Ligia; Roy, Debajyoti; Rodriguez, Alejandro; Vilaclara-Fatjó, Gloria

    2013-04-01

    We analyzed a laminated sedimentary sequence, box core C-2 (30.5 cm length); it was recovered in the eastern part of Pescadero Basin at 670 m depth collected aboard of the R/V "El Puma". Pescadero Basin is one of a series of deep tectonically active basins developed in the Gulf of California from south to north, which are characterized by their distinct climatic, oceanographic and geologic conditions. The purpose for this study is to contribute to the understanding of the paleoceanographic variability during 1000 years in the southern Gulf of California, using geochemical data, X- ray fluorescence and Corg analyses. The Core C-2 is characterized by silty clay sediments with visible laminated structure throughout the core. The preliminary chronology for core C-2 was obtained with the isotopic 210Pb dating method, based on this we estimated a sedimentation rate of 27 mm/yr for the first 5 cm. The data were extrapolated to the base of the core (30.5 cm); according to this the C-2 core covers the period from 900 to 2003 years EC. The geochemical proxies suggest three main changes in sedimentary sequence, considering Al, K, Fe, Si as terrigenous proxies, Ti as precipitation proxy , Zr/Al ratio as aeolian supply proxy and Corg as productivity proxy. At the bottom of the core, low values of Al, K, Si and Fe suggest a decrease in terrigenous input, low values of Ti concentration are associated with reduction in precipitation and high values of the Zr/Al ratio are shown increase aeolian supply. In this context, the proportion of aeolian sediments in the terrigenous record indicates dry conditions.In the middle of the core, high values Al, K, Si and Fe are interpreted to reflect increased terrigenous input, Ti high values suggest an increase in precipitation, low values of Corg reflect diminish in productivity. Also, within the period it is possible to recognize an episode with an abrupt decrease of terrigenous input, but aeolian supply is greater, it suggested a multi

  13. Trading and non-trading period Internet information flow and intraday return volatility

    NASA Astrophysics Data System (ADS)

    Shen, Dehua; Zhang, Wei; Xiong, Xiong; Li, Xiao; Zhang, Yongjie

    2016-06-01

    This paper employs the news appeared in Baidu News as the proxy for Internet information flow, separates them into trading period and non-trading period information and provides alternative evidence for the Mixture of Distribution Hypothesis (MDH). The empirical results show that the contemporary information can effectively reduce the volatility persistence; meanwhile, the lead information and the aggregate information also show some explanatory power. Some future directions are pointed out in the concluding remarks.

  14. Should Age-Period-Cohort Studies Return to the Methodologies of the 1970s?

    PubMed Central

    Masters, Ryan K.; Yang, Y. Claire; Powers, Daniel A.; Zheng, Hui; Land, Kenneth C.

    2015-01-01

    Social scientists have recognized the importance of age-period-cohort (APC) models for half a century, but have spent much of this time mired in debates about the feasibility of APC methods. Recently, a new class of APC methods based on modern statistical knowledge has emerged, offering potential solutions. In 2009, Reither, Hauser and Yang used one of these new methods – hierarchical APC (HAPC) modeling – to study how birth cohorts may have contributed to the U.S. obesity epidemic. They found that recent birth cohorts experience higher odds of obesity than their predecessors, but that ubiquitous period-based changes are primarily responsible for the rising prevalence of obesity. Although these findings have been replicated elsewhere, recent commentaries by Bell and Jones call them into question – along with the new class of APC methods. Specifically, Bell and Jones claim that new APC methods do not adequately address model identification and suggest that “solid theory” is often sufficient to remove one of the three temporal dimensions from empirical consideration. They also present a series of simulation models that purportedly show how the HAPC models estimated by Reither et al. (2009) could have produced misleading results. However, these simulation models rest on assumptions that there were no period effects, and associations between period and cohort variables and the outcome were perfectly linear. Those are conditions under which APC models should never be used. Under more tenable assumptions, our own simulations show that HAPC methods perform well, both in recovering the main findings presented by Reither et al. (2009) and the results reported by Bell and Jones. We also respond to critiques about model identification and theoretically-imposed constraints, finding little pragmatic support for such arguments. We conclude by encouraging social scientists to move beyond the debates of the 1970s and toward a deeper appreciation for modern APC

  15. 26 CFR 1.6038-1 - Information returns required of domestic corporations with respect to annual accounting periods...

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... provisions of this section, any return or any information in any return, required to be filed for a taxable... 26 Internal Revenue 13 2013-04-01 2013-04-01 false Information returns required of domestic... TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Information Returns §...

  16. A 1,000-year, annually-resolved record of hurricane activity from Boston, Massachusetts

    NASA Astrophysics Data System (ADS)

    Besonen, Mark R.; Bradley, Raymond S.; Mudelsee, Manfred; Abbott, Mark B.; Francus, Pierre

    2008-07-01

    The annually-laminated (i.e., varved) sediment record from the Lower Mystic Lake (near Boston, MA), contains a series of anomalous graded beds deposited by strong flooding events that have affected the basin over the last millennium. From the historic portion of the record, 10 out of 11 of the most prominent graded beds correspond with years in which category 2-3 hurricanes are known to have struck the Boston area. Thus, we conclude that the graded beds represent deposition related to intense hurricane precipitation combined with wind-driven vegetation disturbance that exposes fresh, loose sediment. The hurricane signal shows strong, centennial-scale variations in frequency with a period of increased activity between the 12th-16th centuries, and decreased activity during the 11th and 17th-19th centuries. These frequency changes are consistent with other paleoclimate indicators from the tropical North Atlantic, in particular, sea surface temperature variations.

  17. Climate change for the last 1,000 years inferred from borehole temperatures

    NASA Astrophysics Data System (ADS)

    Kitaoka, K.; Arimoto, H.; Hamamoto, H.; Taniguchi, M.; Takeuchi, T.

    2013-12-01

    Subsurface temperatures are an archive of temperature changes occurred at the ground surface in the recent past (Lachenbruch and Marshall, 1986; Pollack, 1993). In order to investigate the local surface temperature histories in Osaka Plane, Japan, we observed subsurface temperatures in existing boreholes, using a thermometer logger. Many temperature-depth profiles within 200 m depth from the ground surface have been obtained, but they show considerable variability. The geological formations in the area consist of horizontally stratified sedimentary layers of about 1,000 m in thickness overlaid on bedrock of granite. There exists a vertical disordered structure in the formations, which may be relating to an active fault (Uemachi fault) in the bedrock (Takemura, et al, 2013). It is considered that groundwater in the horizontal layers cannot move vertically, but can move vertically along the vertical disordered zone. Various temperature profiles might be related to occurrence of vertical groundwater flow in the zone. Analytical models of subsurface temperature which include heat conduction and convection due to vertical groundwater flow in the zone have been constructed under the boundary conditions of prescribing time dependent surface temperature and uniform geothermal flux from greater depths. To solve as one-dimensional problem, heat transfer between the vertical zone and the surrounding medium of no groundwater flow is assumed. Prescribing surface temperatures were given as exponential and periodic functions of the time. Climate change can be considered to comprise both natural and artificial changes. Artificial change, which occurs by the increasing combustion of fossil fuels, is considered roughly to be an exponential increase of the ground surface temperature during the last 150 years. Natural change, which can correlate to solar activity (Lassen and Friis-Christensen, 1995), is assumed roughly to be periodic with the period of about 1200 y at the minimum time

  18. A 1000-year history of large floods in the Upper Ganga catchment, central Himalaya, India

    NASA Astrophysics Data System (ADS)

    Wasson, R. J.; Sundriyal, Y. P.; Chaudhary, Shipra; Jaiswal, Manoj K.; Morthekai, P.; Sati, S. P.; Juyal, Navin

    2013-10-01

    Determining the frequency, magnitude and causes of large floods over long periods in the flood-prone Himalaya is important for estimating the likelihood of future floods. A thousand year record (with some information from 2600 years ago) of the frequency and some estimates of velocities and discharges of large floods has been reconstructed in the Upper Ganga catchment, India, using written reports, litho-stratigraphy and sedimentology, and dated by optical and radiocarbon methods. In the Upper Ganga catchment rainfall triggers large landslides that dam rivers and release large amounts of water when they burst, thereby amplifying the effects of rainfall. The large floods in the catchment may be the result of landslide dam bursts rather than glacial lake bursts, and these are likely to continue and possibly worsen as the monsoon intensifies over the next century. However preliminary information suggests that the recent devastating flood of June 2013 was the result of heavy rainfall not landslide dam bursts. The frequency record is non-random and shows a high frequency between AD 1000 and AD 1300 (omitting uncertainties), then a low frequency until a cluster of floods occurred about 200 years ago, then increased frequency. This temporal pattern is like but not identical with that in Peninsular India, and both appear to be the result of variations in the monsoon.

  19. Modelled rainfall skill assessment against a 1000-year time/space isotope dendro-climatology for southern Africa

    NASA Astrophysics Data System (ADS)

    Woodborne, Stephan; Hall, Grant; Zhang, Qiong

    2016-04-01

    Palaeoclimate reconstruction using isotopic analysis of tree growth increments has yielded a 1000-year record of rainfall variability in southern Africa. Isotope dendro-climatology reconstructions from baobab trees (Adansonia digitata) provide evidence for rainfall variability from the arid Namib Desert and the Limpopo River Valley. Isotopic analysis of a museum specimen of a yellowwood tree (Podocarps falcatus) yields another record from the southwestern part of the subcontinent. Combined with the limited classic denro-climatologies available in the region these records yield palaeo-rainfall variability in the summer and winter rainfall zones as well as the hyper-arid zone over the last 1000 years. Coherent shifts in all of the records indicate synoptic changes in the westerlies, the inter-tropical convergence zone, and the Congo air boundary. The most substantial rainfall shift takes place at about 1600 CE at the onset of the Little Ice Age. Another distinctive feature of the record is a widespread phenomenon that occurs shortly after 1810 CE that in southern Africa corresponds with a widespread social upheaval known as the Difequane or Mfekane. Large scale forcing of the system includes sea-surface temperatures in the Agulhas Current, the El Nino Southern Oscillation and the Southern Annular Mode. The Little Ice Age and Mfekane climate shifts result from different forcing mechanisms, and the rainfall response in the different regions at these times do not have a fixed phase relationship. This complexity provides a good scenario to test climate models. A first order (wetter versus drier) comparison between each of the tree records and a 1000-year palaeoclimate model simulation for the Little Ice Age and Mfekane transitions demonstrates a generally good correspondence.

  20. A system for generating long streamflow records for study of floods of long return period: Phase 2

    SciTech Connect

    Franz, D.D.; Kraeger, B.A.; Linsley, R.K.

    1989-02-01

    Knowledge of the return periods of large floods is required to make risk analyses for nuclear power plants subject to flooding from rivers. The system reported here combined the stochastic simulation of hourly rainfall data and daily pan evaporation data with the deterministic simulation of streamflow by using the synthetic rainfall and evaporation data as input to a calibrated rainfall runoff model. The sequence of annual maximum flood peaks from a synthetic record of 10,000 years or more was then analyzed to obtain estimates of flood frequency. The reasonableness of the flood frequency results must be evaluated on the degree of mimicry of the key characteristics of the observed rainfall data and the ability of the rainfall-runoff model to mimic the observed flood frequency during the calibration period. On this basis, the flood frequency results appeared to be a reasonable extrapolation of the data used in defining the model parameters. There is a need to develop regional parameters for the stochastic models and to conduct research on the relationship between the stochastic structure of rainfall and stochastic structure of flood frequency. The methodology is applicable, assuming a highly skilled analyst, to watersheds similar to those already tested.

  1. 26 CFR 1.6694-4 - Extension of period of collection when tax return preparer pays 15 percent of a penalty for...

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 13 2012-04-01 2012-04-01 false Extension of period of collection when tax return preparer pays 15 percent of a penalty for understatement of taxpayer's liability and certain other procedural matters. 1.6694-4 Section 1.6694-4 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX...

  2. 20 CFR 1002.236 - How is the employee's rate of pay determined when he or she returns from a period of service?

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false How is the employee's rate of pay determined when he or she returns from a period of service? 1002.236 Section 1002.236 Employees' Benefits OFFICE OF THE ASSISTANT SECRETARY FOR VETERANS' EMPLOYMENT AND TRAINING SERVICE, DEPARTMENT OF LABOR REGULATIONS UNDER THE UNIFORMED SERVICES...

  3. 26 CFR 1.6038-2 - Information returns required of United States persons with respect to annual accounting periods...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... establishes to the satisfaction of the district director or the director of the service center that the person... respect to which a return is filed, include banking transactions entered into on behalf of customers;...

  4. Two Extreme Climate Events of the Last 1000 Years Recorded in Himalayan and Andean Ice Cores: Impacts on Humans

    NASA Astrophysics Data System (ADS)

    Thompson, L. G.; Mosley-Thompson, E. S.; Davis, M. E.; Kenny, D. V.; Lin, P.

    2013-12-01

    In the last few decades numerous studies have linked pandemic influenza, cholera, malaria, and viral pneumonia, as well as droughts, famines and global crises, to the El Niño-Southern Oscillation (ENSO). Two annually resolved ice core records, one from Dasuopu Glacier in the Himalaya and one from the Quelccaya Ice Cap in the tropical Peruvian Andes provide an opportunity to investigate these relationships on opposite sides of the Pacific Basin for the last 1000 years. The Dasuopu record provides an annual history from 1440 to 1997 CE and a decadally resolved record from 1000 to 1440 CE while the Quelccaya ice core provides annual resolution over the last 1000 years. Major ENSO events are often recorded in the oxygen isotope, insoluble dust, and chemical records from these cores. Here we investigate outbreaks of diseases, famines and global crises during two of the largest events recorded in the chemistry of these cores, particularly large peaks in the concentrations of chloride (Cl-) and fluoride (Fl-). One event is centered on 1789 to 1800 CE and the second begins abruptly in 1345 and tapers off after 1360 CE. These Cl- and F- peaks represent major droughts and reflect the abundance of continental atmospheric dust, derived in part from dried lake beds in drought stricken regions upwind of the core sites. For Dasuopu the likely sources are in India while for Quelccaya the sources would be the Andean Altiplano. Both regions are subject to drought conditions during the El Niño phase of the ENSO cycle. These two events persist longer (10 to 15 years) than today's typical ENSO events in the Pacific Ocean Basin. The 1789 to 1800 CE event was associated with a very strong El Niño event and was coincidental with the Boji Bara famine resulting from extended droughts that led to over 600,000 deaths in central India by 1792. Similarly extensive droughts are documented in Central and South America. Likewise, the 1345 to 1360 CE event, although poorly documented

  5. On the effect of the sampling frequency of sea level measurements on return period estimate of extremes—Southern European examples

    NASA Astrophysics Data System (ADS)

    Tsimplis, M. N.; Marcos, M.; Pérez, B.; Challenor, P.; Garcia-Fernandez, M. J.; Raicich, F.

    2009-10-01

    Estimates of extreme sea levels and return periods have been based mainly on hourly sampling rates. Technological development has enabled the sampling rates to increase and sampling rates of 5-10 min are becoming increasingly common. In this paper we explore the relationship between extreme sea levels and estimated return periods based on hourly and shorter sampling periods in three tide-gauges one at the Atlantic coasts of Spain (Coruña), one in the western Mediterranean (Malaga) and one in the N. Adriatic (Trieste). Significant differences of several centimetres are found in the hourly and 5 min extremes. These reflect in significant underestimation of the 50-year return levels which in Trieste reach 38 cm. A theoretical relationship between the high and the low sampling rate of extremes is also tested. Thus updated 50-year return levels for the Mediterranean and the coasts of the Iberian peninsula are produced assuming that the differences identified in the various stations generalise to other tide-gauge (hourly) records for which hourly values have been analysed earlier.

  6. The surface impact of stratospheric sudden warmings in a 1000 year control simulation: sensitivity to event definition and type

    NASA Astrophysics Data System (ADS)

    Maycock, Amanda

    2014-05-01

    Major sudden stratospheric warmings (SSWs) are characterised by large departures of the northern hemisphere winter-time circulation from climatology. Numerous studies have shown that on average these events impact on tropospheric weather patterns leading to a more negative North Atlantic Oscillation index; however, recent studies have suggested that the nature of this downward coupling may be sensitive to the type of SSW (vortex split or displacement). This study explores this issue using a 1000 year pre-industrial control simulation from the IPSL-CM5A-LR model taken from the CMIP5 archive. We identify SSW events using two distinct methods: the widely applied algorithm of Charlton and Polvani (2007) and a 2-D moments-based approach described by Seviour et al (2013). The long simulation offers a unique opportunity to analyse a very large sample of SSW events (~500). We evaluate the relative timing and frequency of SSWs identified by the two methods and examine their impact on the tropospheric state. In contrast to other recent studies, we do not find a significant difference between the impact of split and displacement SSWs on the troposphere in this model. We analyse the evolution of the SSWs that are not consistently identified by the two algorithms, and examine whether they have a significant role in determining the overall impact of SSWs on the troposphere. The large number of warming events enables a comprehensive assessment of the noise that may be associated with analysing stratosphere-troposphere coupling in smaller sample sizes.

  7. Estimation of floods with long return period using continuous simulation within the framework of the limits of acceptability approach

    NASA Astrophysics Data System (ADS)

    Beven, K.; Blazkova, S.

    2009-04-01

    The estimation of flood frequency by continuous simulation provides an alternative method to direct statistical estimation for catchments where there are limited historical records of flood peaks. We are presenting the extended GLUE multiple limits of acceptability calibration strategy in which models are treated as hypotheses about system response, to be rejected if the predictions fall outside of the limits of acceptability. Flood frequency predictions on the Skalka catchment in the Czech Republic (672 km2, range of altitudes from 460 to 1041 m a.s.l.), are compared against summary information of rainfall characteristics, the flow duration curve, and the frequency characteristics of flood discharges and snow water equivalent. Limits of acceptability have been defined, prior to running the Monte Carlo model realisations. Since we have identified only 39 behavioural models we have relaxed the limits of acceptability using a procedure of scoring deviations relative to the limits, to identify the minimum extension across all criteria (together 114 criteria) to obtain a sample of 4192 parameter sets that were accepted as potentially useful in prediction. Long term simulations of 10000 years for retained models were used to obtain uncertain estimates of the 1000 year peak required for the assessment of dam safety at the catchment outlet. We also demonstrate the effect of different input realisations on acceptability. Taking just one of the behavioural parameter sets and generating 10,000 input sequences of the same length as the observed flood series results in a range of critical values for acceptability across a range of evaluation criteria.

  8. 26 CFR 1.6038-2 - Information returns required of United States persons with respect to annual accounting periods...

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 13 2011-04-01 2011-04-01 false Information returns required of United States... 31, 1962. 1.6038-2 Section 1.6038-2 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE... foreign corporation. A person in control of a corporation which, in turn, owns more than 50 percent of...

  9. 26 CFR 1.6038-2 - Information returns required of United States persons with respect to annual accounting periods...

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 26 Internal Revenue 13 2013-04-01 2013-04-01 false Information returns required of United States... 31, 1962. 1.6038-2 Section 1.6038-2 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE... foreign corporation. A person in control of a corporation which, in turn, owns more than 50 percent of...

  10. 26 CFR 1.6038-2 - Information returns required of United States persons with respect to annual accounting periods...

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 13 2012-04-01 2012-04-01 false Information returns required of United States... 31, 1962. 1.6038-2 Section 1.6038-2 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE... foreign corporation. A person in control of a corporation which, in turn, owns more than 50 percent of...

  11. Turnip mosaic potyvirus probably first spread to Eurasian brassica crops from wild orchids about 1000 years ago.

    PubMed

    Nguyen, Huy D; Tomitaka, Yasuhiro; Ho, Simon Y W; Duchêne, Sebastián; Vetten, Heinrich-Josef; Lesemann, Dietrich; Walsh, John A; Gibbs, Adrian J; Ohshima, Kazusato

    2013-01-01

    Turnip mosaic potyvirus (TuMV) is probably the most widespread and damaging virus that infects cultivated brassicas worldwide. Previous work has indicated that the virus originated in western Eurasia, with all of its closest relatives being viruses of monocotyledonous plants. Here we report that we have identified a sister lineage of TuMV-like potyviruses (TuMV-OM) from European orchids. The isolates of TuMV-OM form a monophyletic sister lineage to the brassica-infecting TuMVs (TuMV-BIs), and are nested within a clade of monocotyledon-infecting viruses. Extensive host-range tests showed that all of the TuMV-OMs are biologically similar to, but distinct from, TuMV-BIs and do not readily infect brassicas. We conclude that it is more likely that TuMV evolved from a TuMV-OM-like ancestor than the reverse. We did Bayesian coalescent analyses using a combination of novel and published sequence data from four TuMV genes [helper component-proteinase protein (HC-Pro), protein 3(P3), nuclear inclusion b protein (NIb), and coat protein (CP)]. Three genes (HC-Pro, P3, and NIb), but not the CP gene, gave results indicating that the TuMV-BI viruses diverged from TuMV-OMs around 1000 years ago. Only 150 years later, the four lineages of the present global population of TuMV-BIs diverged from one another. These dates are congruent with historical records of the spread of agriculture in Western Europe. From about 1200 years ago, there was a warming of the climate, and agriculture and the human population of the region greatly increased. Farming replaced woodlands, fostering viruses and aphid vectors that could invade the crops, which included several brassica cultivars and weeds. Later, starting 500 years ago, inter-continental maritime trade probably spread the TuMV-BIs to the remainder of the world. PMID:23405136

  12. Evidence of Authentic DNA from Danish Viking Age Skeletons Untouched by Humans for 1,000 Years

    PubMed Central

    Melchior, Linea; Kivisild, Toomas; Lynnerup, Niels; Dissing, Jørgen

    2008-01-01

    Background Given the relative abundance of modern human DNA and the inherent impossibility for incontestable proof of authenticity, results obtained on ancient human DNA have often been questioned. The widely accepted rules regarding ancient DNA work mainly affect laboratory procedures, however, pre-laboratory contamination occurring during excavation and archaeological-/anthropological handling of human remains as well as rapid degradation of authentic DNA after excavation are major obstacles. Methodology/Principal Findings We avoided some of these obstacles by analyzing DNA from ten Viking Age subjects that at the time of sampling were untouched by humans for 1,000 years. We removed teeth from the subjects prior to handling by archaeologists and anthropologists using protective equipment. An additional tooth was removed after standard archaeological and anthropological handling. All pre-PCR work was carried out in a “clean- laboratory” dedicated solely to ancient DNA work. Mitochondrial DNA was extracted and overlapping fragments spanning the HVR-1 region as well as diagnostic sites in the coding region were PCR amplified, cloned and sequenced. Consistent results were obtained with the “unhandled” teeth and there was no indication of contamination, while the latter was the case with half of the “handled” teeth. The results allowed the unequivocal assignment of a specific haplotype to each of the subjects, all haplotypes being compatible in their character states with a phylogenetic tree drawn from present day European populations. Several of the haplotypes are either infrequent or have not been observed in modern Scandinavians. The observation of haplogroup I in the present study (<2% in modern Scandinavians) supports our previous findings of a pronounced frequency of this haplogroup in Viking and Iron Age Danes. Conclusion The present work provides further evidence that retrieval of ancient human DNA is a possible task provided adequate precautions are taken and well-considered sampling is applied. PMID:18509537

  13. Challenges in Parameterizing a Landscape Evolution Model to Predict 1000 Years of Erosion on a Mesa-top Waste Repository

    NASA Astrophysics Data System (ADS)

    Wilson, C. J.; Crowell, K. J.; Lane, L. J.

    2004-12-01

    Low-level radioactive waste from operations at Los Alamos National Laboratory is currently being disposed in pits excavated into mesa-top repositories. One requirement for operation of the repositories is that no release of radioactive material will occur for up to 1000 years following closure of the repository. LANL is required to demonstrate that the repository can be successfully closed; including demonstrating that the waste pits will not be excavated by long term surface erosion processes. Here we describe the parameterization and application of the Siberia landscape evolution model in the optimization of the closure cap design for the Material Disposal Site G at LANL. The closure design is particularly challenging since some of the older waste pits are located near the edges of a slender finger mesa with complex topography. LANL scientists worked with the cap design engineer at URS in an iterative process to develop a stable design. In addition to design challenges, we faced significant challenges parameterizing the Siberia model for our site. Although we had multiple rainfall, runoff and sediment data sets at a range of scales (plot, first order basin and watershed), these data were not complete enough to develop the relationships required to parameterize Siberia. The data did however provide a strong realty-check on rainfall-runoff and runoff-sediment yield relationships derived from the IRS9 and Hillslope Erosion (HEM) models respectively, which were ultimately used to develop parameter values for the fluvial erosion in Siberia. Diffusion was constrained by eye-balling a match between Siberia generated topography and the observed topography (field and ALSM data) at the heads of first order channels. Siberia runs that generated colluvial hollows (non-existent at this site) indicated that the diffusion coefficient was too high. LA-UR-04-6328.

  14. The Discovery of America: The first Americans may have swept the Western Hemisphere and decimated its fauna within 1000 years.

    PubMed

    Martin, P S

    1973-03-01

    I propose a new scenario for the discovery of America. By analogy with other successful animal invasions, one may assume that the discovery of the New World triggered a human population explosion. The invading hunters attained their highest population density along a front that swept from Canada to the Gulf of Mexico in 350 years, and on to the tip of South America in roughly 1000 years. A sharp drop in human population soon followed as major prey animals declined to extinction. Possible values for the model include an average frontal depth of 160 kilometers, an average population density of 0.4 person per square kilometer on the front and of 0.04 person per square kilometer behind the front, and an average rate of frontal advance of 16 kilometers per year. For the first two centuries the maximum rate of growth may have equaled the historic maximum of 3.4 percent annually. During the episode of faunal extinctions, the population of North America need not have exceeded 600,000 people at any one time. The model generates a population sufficiently large to overkill a biomass of Pleistocene large animals averaging 9 metric tons per square kilometer (50 animal units per section) or 2.3 x 10(8) metric tons in the hemisphere. It requires that on the front one person in four destroy one animal unit (450 kilograms) per week, or 26 percent of the biomass of an average section in 1 year in any one region. Extinction would occur within a decade. There was insufficient time for the fauna to learn defensive behaviors, or for more than a few kill sites to be buried and preserved for the archeologist. Should the model survive future findings, it will mean that the extinction chronology of the Pleistocene megafauna can be used to map the spread of Homo sapiens throughout the New World. PMID:17842155

  15. Turnip Mosaic Potyvirus Probably First Spread to Eurasian Brassica Crops from Wild Orchids about 1000 Years Ago

    PubMed Central

    Nguyen, Huy D.; Tomitaka, Yasuhiro; Ho, Simon Y. W.; Duchêne, Sebastián; Vetten, Heinrich-Josef; Lesemann, Dietrich; Walsh, John A.; Gibbs, Adrian J.; Ohshima, Kazusato

    2013-01-01

    Turnip mosaic potyvirus (TuMV) is probably the most widespread and damaging virus that infects cultivated brassicas worldwide. Previous work has indicated that the virus originated in western Eurasia, with all of its closest relatives being viruses of monocotyledonous plants. Here we report that we have identified a sister lineage of TuMV-like potyviruses (TuMV-OM) from European orchids. The isolates of TuMV-OM form a monophyletic sister lineage to the brassica-infecting TuMVs (TuMV-BIs), and are nested within a clade of monocotyledon-infecting viruses. Extensive host-range tests showed that all of the TuMV-OMs are biologically similar to, but distinct from, TuMV-BIs and do not readily infect brassicas. We conclude that it is more likely that TuMV evolved from a TuMV-OM-like ancestor than the reverse. We did Bayesian coalescent analyses using a combination of novel and published sequence data from four TuMV genes [helper component-proteinase protein (HC-Pro), protein 3(P3), nuclear inclusion b protein (NIb), and coat protein (CP)]. Three genes (HC-Pro, P3, and NIb), but not the CP gene, gave results indicating that the TuMV-BI viruses diverged from TuMV-OMs around 1000 years ago. Only 150 years later, the four lineages of the present global population of TuMV-BIs diverged from one another. These dates are congruent with historical records of the spread of agriculture in Western Europe. From about 1200 years ago, there was a warming of the climate, and agriculture and the human population of the region greatly increased. Farming replaced woodlands, fostering viruses and aphid vectors that could invade the crops, which included several brassica cultivars and weeds. Later, starting 500 years ago, inter-continental maritime trade probably spread the TuMV-BIs to the remainder of the world. PMID:23405136

  16. The ˜1000-years BP explosive eruption of Caldeira Volcano (Faial, Azores): the first stage of incremental caldera formation

    NASA Astrophysics Data System (ADS)

    Pimentel, Adriano; Pacheco, José; Self, Stephen

    2015-05-01

    The ˜1000-years BP eruption of Caldeira Volcano (Faial Island) was one of the last major explosive events recorded in the Azores. It produced a complex succession of pyroclastic deposits, known as the C11, divided into three members. At the base is the Brejo Member, a sequence of fine- to coarse-grained parallel-bedded ash layers found in the NW sector of the island. The middle part corresponds to the Inverno Member, a coarse-grained massive pumice fall deposit, restricted to the north flank of Caldeira Volcano. The top is dominated by the Cedros Member which includes massive to diffuse-stratified lapilli-ash and lithic breccias, exposed along the north and east flanks of the volcano. A minimum bulk volume of at least 0.22 km3 (>0.1 km3 dense rock equivalent (DRE)) is estimated for the C11 eruption, although a large portion may have been deposited offshore. The juvenile products are trachytic (59 wt% SiO2) with a homogenous whole-rock composition and mineral assemblage throughout the pyroclastic succession. However, petrographic and groundmass glass analyses indicate magma mingling/mixing processes between two trachytic batches. The C11 eruption history is divided into three phases (following the member division) with distinct eruptive styles: (1) an initial phreatomagmatic phase caused by rising magma (˜950 °C) encountering a crater pond or aquifer, (2) a fall-dominated phase which established a sub-Plinian column up to 14 km high (mass eruption rate (MER) of 1.2 × 107 kg/s) and (3) prolonged pyroclastic fountaining and sustained quasi-steady pyroclastic density current generation followed by summit collapse. The C11 eruption is interpreted as the first stage in the formation of an incremental caldera. This study provides valuable insights for a better understanding of small but complex explosive eruptions and their impact on ocean islands.

  17. Geochemical evidence of past earthquakes in sediments of the Reloncaví fjord (Chilean Patagonia) during the last ˜ 1000 years

    NASA Astrophysics Data System (ADS)

    Rebolledo, Lorena; Lange, Carina; Muñoz, Práxedes; Salamanca, Marco

    2014-05-01

    The Chilean fjords are excellent archives of paleoearthquakes, tsunamis and landslides (St-Onge et al., 2012 in Sedimentary Geology 243-244: 89-107). Here we report on new sedimentological and geochemical evidence of past earthquakes in sediments of the Reloncavi fjord, Northern Patagonia (41° S, 72° W), during the last ~1000 years. We recovered four sediment cores from the Reloncaví fjord (RH-5B, RH-5C, RH-6B, RH7B, water depth range = 90-260 m; core length range = 45-75 cm). Age models were based on 210Pb, AMS-14C and the first appearance of the diatom Rhizosolenia setigera cf. pungens in the fossil record as statigraphic marker. The cores span the last ~122 to 800 years of sedimentation with sedimentation rates ranging between 0.1 and 0.24 cm yr-1. The cores revealed evidence of turbidites associated with the historical earthquakes of 1960, 1837, 1737 and 1575 AD, and an earlier period for which there is no historical information, 1200-1400 AD. The turbidites exhibit a grading-up pattern with sand layers, and are characterized by a decrease in organic carbon and biogenic opal, an increase in the C/N molar ratio, negative values of δ13Corg(average -27),and an increase in the relative abundance of Paralia sulcata, a diatom associated with sandy environments, being the turbite layers mainly freshwater in origen. We suggest that these turbidite layers were triggered by past earthquakes that produced movement of land from the cliff areas that surround the Reloncaví fjord. Funding: Project FONDECYT # 11110103 and COPAS Sur-Austral project PFB-31.

  18. Archaea and bacteria with surprising microdiversity show shifts in dominance over 1,000-year time scales in hydrothermal chimneys

    PubMed Central

    Brazelton, William J.; Ludwig, Kristin A.; Sogin, Mitchell L.; Andreishcheva, Ekaterina N.; Kelley, Deborah S.; Shen, Chuan-Chou; Edwards, R. Lawrence; Baross, John A.

    2010-01-01

    The Lost City Hydrothermal Field, an ultramafic-hosted system located 15 km west of the Mid-Atlantic Ridge, has experienced at least 30,000 years of hydrothermal activity. Previous studies have shown that its carbonate chimneys form by mixing of ∼90 °C, pH 9–11 hydrothermal fluids and cold seawater. Flow of methane and hydrogen-rich hydrothermal fluids in the porous interior chimney walls supports archaeal biofilm communities dominated by a single phylotype of Methanosarcinales. In this study, we have extensively sampled the carbonate-hosted archaeal and bacterial communities by obtaining sequences of >200,000 amplicons of the 16S rRNA V6 region and correlated the results with isotopic (230Th) ages of the chimneys over a 1,200-year period. Rare sequences in young chimneys were commonly more abundant in older chimneys, indicating that members of the rare biosphere can become dominant members of the ecosystem when environmental conditions change. These results suggest that a long history of selection over many cycles of chimney growth has resulted in numerous closely related species at Lost City, each of which is preadapted to a particular set of reoccurring environmental conditions. Because of the unique characteristics of the Lost City Hydrothermal Field, these data offer an unprecedented opportunity to study the dynamics of a microbial ecosystem’s rare biosphere over a thousand-year time scale. PMID:20080654

  19. Determination of snow avalanche return periods using a tree-ring based reconstruction in the French Alps: cross validation with the predictions of a statistical-dynamical model

    NASA Astrophysics Data System (ADS)

    Schläppy, Romain; Eckert, Nicolas; Jomelli, Vincent; Grancher, Delphine; Brunstein, Daniel; Stoffel, Markus; Naaim, Mohamed

    2013-04-01

    Documenting past avalanche activity represents an indispensable step in avalanche hazard assessment. Nevertheless, (i) archival records of past avalanche events do not normally yield data with satisfying spatial and temporal resolution and (ii) precision concerning runout distance is generally poorly defined. In addition, historic documentation is most often (iii) biased toward events that caused damage to structure or loss of life on the one hand and (iv) undersampled in unpopulated areas on the other hand. On forested paths dendrogeomorphology has been demonstrated to represent a powerful tool to reconstruct past activity of avalanches with annual resolution and for periods covering the past decades to centuries. This method is based on the fact that living trees may be affected by snow avalanches during their flow and deposition phases. Affected trees will react upon these disturbances with a certain growth response. An analysis of the responses recorded in tree rings coupled with an evaluation of the position of reacting trees within the path allows the dendrogeomorphic expert to identify past snow avalanche events and deduced their minimum runout distance. The objective of the work presented here is firstly to dendrochronogically -reconstruct snow avalanche activity in the Château Jouan path located near Montgenèvre in the French Alps. Minimal runout distances are then determined for each reconstructed event by considering the point of further reach along the topographic profile. Related empirical return intervals are evaluated, combining the extent of each event with the average local frequency of the dendrological record. In a second step, the runout distance distribution derived from dendrochronological reconstruction is compared to the one derived from historical archives and to high return period avalanches predicted by an up-to-date locally calibrated statistical-numerical model. It appears that dendrochronological reconstructions correspond mostly to

  20. Experimental medicine 1000 years ago

    PubMed Central

    Abdel-Halim, Rabie E.

    2011-01-01

    Little is known about the state of experimentation in the field of medicine during the Medieval Islamic era. With few exceptions, most of the contemporary sources on history of medicine propagate the idea that the roots of experimental medicine in its modern form, including clinical trials and drug-potency studies, first started during the European Renaissance in the 16th to the 18th centuries. This study is part of an ongoing multidisciplinary primary-source investigation of the original Arabic works of 11 Islamic medical scholars who lived and practiced between the 9th and the 13th centuries. The study critically evaluated and documented their contributions to the development of the scientific method and experimental medicine during that medieval Islamic era in several areas including critical appraisal of previous knowledge, clinical observations and case reports, clinical therapeutic trials, drug potency trials, experimentation on animals, dissection and dissection experiments as well as postmortem examinations. In each of the above-mentioned areas, significant contributions were made during the Medieval Islamic era from as early as the ninth century AD. PMID:21747591

  1. Experimental medicine 1000 years ago.

    PubMed

    Abdel-Halim, Rabie E

    2011-05-01

    Little is known about the state of experimentation in the field of medicine during the Medieval Islamic era. With few exceptions, most of the contemporary sources on history of medicine propagate the idea that the roots of experimental medicine in its modern form, including clinical trials and drug-potency studies, first started during the European Renaissance in the 16(th) to the 18(th) centuries. This study is part of an ongoing multidisciplinary primary-source investigation of the original Arabic works of 11 Islamic medical scholars who lived and practiced between the 9(th) and the 13(th) centuries. The study critically evaluated and documented their contributions to the development of the scientific method and experimental medicine during that medieval Islamic era in several areas including critical appraisal of previous knowledge, clinical observations and case reports, clinical therapeutic trials, drug potency trials, experimentation on animals, dissection and dissection experiments as well as postmortem examinations. In each of the above-mentioned areas, significant contributions were made during the Medieval Islamic era from as early as the ninth century AD. PMID:21747591

  2. Long Return Periods for Earthquakes in San Gorgonio Pass and Implications for Large Ruptures of the San Andreas Fault in Southern California

    NASA Astrophysics Data System (ADS)

    Yule, J.; McBurnett, P.; Ramzan, S.

    2011-12-01

    The largest discontinuity in the surface trace of the San Andreas fault occurs in southern California at San Gorgonio Pass. Here, San Andreas motion moves through a 20 km-wide compressive stepover on the dextral-oblique-slip thrust system known as the San Gorgonio Pass fault zone. This thrust-dominated system is thought to rupture during very large San Andreas events that also involve strike-slip fault segments north and south of the Pass region. A wealth of paleoseismic data document that the San Andreas fault segments on either side of the Pass, in the San Bernardino/Mojave Desert and Coachella Valley regions, rupture on average every ~100 yrs and ~200 yrs, respectively. In contrast, we report here a notably longer return period for ruptures of the San Gorgonio Pass fault zone. For example, features exposed in trenches at the Cabezon site reveal that the most recent earthquake occurred 600-700 yrs ago (this and other ages reported here are constrained by C-14 calibrated ages from charcoal). The rupture at Cabezon broke a 10 m-wide zone of east-west striking thrusts and produced a >2 m-high scarp. Slip during this event is estimated to be >4.5 m. Evidence for a penultimate event was not uncovered but presumably lies beneath ~1000 yr-old strata at the base of the trenches. In Millard Canyon, 5 km to the west of Cabezon, the San Gorgonio Pass fault zone splits into two splays. The northern splay is expressed by 2.5 ± 0.7 m and 5.0 ± 0.7 m scarps in alluvial terraces constrained to be ~1300 and ~2500 yrs old, respectively. The scarp on the younger, low terrace postdates terrace abandonment ~1300 yrs ago and probably correlates with the 600-700 yr-old event at Cabezon, though we cannot rule out that a different event produced the northern Millard scarp. Trenches excavated in the low terrace reveal growth folding and secondary faulting and clear evidence for a penultimate event ~1350-1450 yrs ago, during alluvial deposition prior to the abandonment of the low terrace

  3. 50-year return-period wet-snow load estimation based on weather station data for overhead line design in France

    NASA Astrophysics Data System (ADS)

    Ducloux, H.; Nygaard, B. E.

    2014-11-01

    Historically, as far as wet-snow loads were concerned, overhead line design was often based on experience or long-term applications with positive results. New standard like CENELEC EN 580341-1 (2012) take into account characteristic loads, i.e. 50-year return-period loads, for the overhead line design. This article proposes a method to estimate characteristic wet-snow loads based on meteorological data recorded at weather stations. The model used to calculate those loads is mainly inspired by a recent article written by Nygaard et al. (2013a) in which a new parameterization is proposed for the classical cylindrical wet-snow accretion model, as described in ISO 12494 standard (2001), annex C. After a complete description of the model and its parameterization adapted to French wet-snow events, the statistical issues are examined. Then, the model is used with the meteorological data of 87 weather stations in order to calculate wet-snow loads whose relevance has been positively tested according to real damages recorded in a complete wet-snow event database. At last, the characteristic loads of those 87 stations have been determined according to all the loads generated by the model and processed by a peak-over-threshold (POT) method. A practical method to determine the 90% confidence intervals of those characteristic values is given. As it is demonstrated that there is only one value of the ice class (IC) masses proposed by ISO 12494 in each confidence interval, characteristic loads can be easily expressed in terms of ICs. That method shows that ICs ranging from R1 (0.5 kg m-1) to R5 (5 kg m-1) could be used for overhead line design in France.

  4. Peatland Carbon Accumulation in Southern Alaska During the Past 1000 Years: A Comparative Study of Hydrology and Carbon Accumulation in Four Peatlands

    NASA Astrophysics Data System (ADS)

    Klein, E. S.; Booth, R. K.; Yu, Z.

    2012-12-01

    North American peatlands are the largest C reservoir of any ecosystem type, and Alaskan peatlands contain greater than half of the C storage of United States' peatlands. Peatland C accumulation rates (PCAR) are controlled by the relative rates of production and decomposition, and the rate of these processes is affected by many factors, including temperature, hydrology, and vegetation. Understanding how this carbon pool will respond to climate changes is important for evaluating potential earth-system feedbacks. Critical to this goal is a better understanding of how PCAR varies among different climate zones and peatland types. We developed coupled studies of peatland paleohydrology and PCAR from four different Sphagnum-dominated peatlands in Alaska, two in the Southcentral (SC) region and two in the wetter and warmer Southeast (SE) region. Peatland types included a kettle peatland perched on a moraine and a lowland peatland occupying a paleo outwash channel in the SC region, as well as a raised peatland and a sloping peatland in the SE region. Past PCAR and hydrology of these peatlands, inferred from testate amoebae and loss-on-ignition analyses, were compared to well-documented climate and temperature changes of the past 1000 years, like the Medieval Climate Anomaly (MCA) and the Little Ice Age (LIA). Results indicate heterogeneous patterns of PCAR at the four sites. For example, the raised peatland in the SE region had an average PCAR of 52 gC/m2/yr, whereas the other three sites had average values between 31-35 gC/m2/yr. Interestingly, testate amoebae indicated that the raised peatland had the driest average surface-moisture among the sites, possibly suggesting high temperature sensitivity to PCAR. Temporal patterns of PCAR also varied considerably among sites, with peatlands in the SE region exhibiting somewhat greater centennial-scale variability in PCAR during the past 1000 years than those of the SC region. Reconstructed water-table depths were also more

  5. Multi-Scale Reconstructions of Snowpack Variability for Key Watersheds in Western North America: Tree-Rings Provide Insights on the Past 500 to 1000 Years

    NASA Astrophysics Data System (ADS)

    Pederson, G. T.; Gray, S. T.; Fagre, D. B.; Graumlich, L. J.

    2008-12-01

    One of the most robust lines of evidence for climate change impacts in the Western US is the decline in snowpack during the latter half of the 20th century. It is critical to ascertain whether this trend is anomalous relative to long-term patterns of snowpack dynamics. We are using tree-ring data networks coupled with NRCS snowcourse based reconstructions of Snow Water Equivalent (SWE) to reconstruct snowpack variability at multiple watershed scales. Snowcourse records provide the raw data needed to generate calibration datasets of April 1 SWE. Records span 1930 to present, and were utilized to generate historic SWE anomalies from the scale of individual USGS level 6 watershed to the entire Upper Colorado River Basin. Across multiple watershed scales historic SWE records were used in combination with more then 600 existing and recently collected tree-ring chronologies to produce 500 to 1000 year records of April 1 SWE variability. Initial work targets key high-mountain headwaters for the Upper Colorado, Upper Yellowstone/Missouri, and Columbia/Saskatchewan Rivers. For the Colorado Plateau region, 9 out of 17 level 6 watersheds achieve quality reconstructions (R2> 0.45) of April 1 SWE, and a reconstruction extending back to 1181 AD was produced for the entire Upper Colorado River Basin. Preliminary analyses show marked interannual to multidecadal variability in total April 1 SWE. Comparisons with existing proxy records of Pacific Basin climate show coupled ENSO and PDO influences on the total amount of mountain snowpack in these regions. The strength and sign of these relationships is shown to vary over time and on a watershed-by- watershed basis. These and other results exemplify why long-term records are essential baseline information for evaluating recent and future changes in mountain snowpack. The overarching goal of this project is to lay the foundation for snowpack reconstructions that encompass high mountain areas in all of western North America.

  6. Identifying coherent patterns of environmental change between multiple, multivariate records: an application to four 1000-year diatom records from Victoria, Australia

    NASA Astrophysics Data System (ADS)

    Tyler, Jonathan J.; Mills, Keely; Barr, Cameron; Sniderman, J. M. Kale; Gell, Peter A.; Karoly, David J.

    2015-07-01

    Empirical orthogonal functions (EOFs) of indirect archives of environmental change are increasingly used to identify coherent trends between palaeoclimate records, to separate externally forced patterns from locally driven idiosyncrasies. Lake sediments are particularly suited to such syntheses: they are abundant in most landscapes and record a wide array of information, yet local complexities often conceal or confuse the climate signal recorded at individual sites. Lake sediment parameters usually exhibit non-linear, multivariate and indirect responses to climate, therefore identifying coherent patterns between two or more lake records presents a complex challenge. Ideally, the selection of representative variables should be non-subjective and inclusive of as many different variables as possible, allowing for unexpected correlations between sites. In order to meet such demands, we propose a two-tier ordination procedure whereby site-specific (local) ordinations, obtained using Detrended Correspondence Analysis (DCA), are nested within a second, regional EOF. Using the local DCAs as representative variables allows the retention of a larger fraction of variance from each site, removes any subjectivity from variable selection and retains the potential for observing multiple, coherent signals from within and between each dataset. We explore this potential using four decadally resolved diatom records from volcanic lakes in Western Victoria, Australia. The records span the 1000 years prior to European settlement in CE 1803. Our analyses reveal at least two coherent patterns of ecological change that are manifest in each of the four datasets, patterns which may have been overlooked by a single-variable, empirical orthogonal function approach. This intra-site coherency provides a valuable step towards understanding multi-decadal hydroclimate variability in southeastern Australia.

  7. 1000 years of climate variability in central Asia: assessing the evidence using Lake Baikal (Russia) diatom assemblages and the application of a diatom-inferred model of snow cover on the lake

    NASA Astrophysics Data System (ADS)

    Mackay, Anson W.; Ryves, D. B.; Battarbee, R. W.; Flower, R. J.; Jewson, D.; Rioual, P.; Sturm, M.

    2005-04-01

    The mainly endemic phytoplankton record of Lake Baikal has been used in this study to help interpret climate variability during the last 1000 years in central Asia. The diatom record was derived from a short core taken from the south basin and has been shown to be free from any sedimentary heterogeneities. We employ here a diatom-based inference model of snow accumulation on the frozen lake for the first time ( r2boot=0.709; RMSEP=0.120 log cm). However, palaeoenvironmental reconstructions have been improved by the use of correction factors, specifically developed for the dominant phytoplankton ( Aulacoseira baicalensis, Aulacoseira skvortzowii, Cyclotella minuta, Stephanodiscus meyerii and Synedra acus) in the south basin of Lake Baikal. Cluster analysis identifies three significant zones in the core, zone 1 (c. 880 AD-c. 1180 AD), zone 2 (c. 1180-1840 AD) and zone 3 (c. 1840-1994 AD), coincident with the Medieval Warm Period (MWP), the Little Ice Age (LIA) and the period of recent warming, respectively. Our results indicate that S. acus dominated the diatom phytoplankton within zone 1 coincident with the MWP. S. acus is an opportunistic species that is able to increase its net growth when A. baicalensis does not. During this period, conditions are likely to have been unfavourable for the net increases in A. baicalensis growth due to the persistence of warm water in the lake, together with an increased length of summer stratification and delay in timing of the autumnal overturn. In zone 2, spring diatom crops blooming under the ice declined in abundances due in part to increased winter severity and snow cover on the lake. Accumulating snow on the lake is likely to have arisen from increased anticyclonic activity, resulting in prolonged winters expressed during the LIA. Thick, accumulating snow cover inhibits light penetration through the ice, thereby having negative effects on cell division rate and extent of turbulence underneath the ice. Consequently, only taxa

  8. A 1,000 year annually resolved record of speleothem δ18O from Northern Spain; a potential new proxy for North Atlantic Oscillation (NAO) index reconstruction

    NASA Astrophysics Data System (ADS)

    Comas-Bru, L.; McDermott, F.; Fleitmann, D.

    2012-04-01

    The North Atlantic Oscillation (NAO) is defined as the normalized pressure difference between the Azores and Iceland, and is the most prominent mode of climate variability during boreal winter (December to March) over a large region of the Northern Hemisphere from eastern North America to Siberia, and from the Arctic to the subtropical Atlantic. The NAO is responsible for much of the inter-annual variability in mean wind speed and direction, heat and moisture transport between the Atlantic and the surrounding areas, as well as the intensity, number and trajectory of storm tracks (Hurrell et al., 1995). An instrumental NAO index has been compiled by the Climate Research Unit at the University of East Anglia, extending back to 1821. In this study, a lamina counted record of δ18O from stalagmite GAR-02 from La Garma cave (in northern Spain) is presented as a new proxy to extend the instrumental NAO index back through the last 1,000 years. The stalagmite measures 1140 mm in length and was collected during 2005. Before collection, the stalagmite was fed by a 150 mm long stalactite, which provided a relatively constant drip rate. The stalagmite preserves clear annual laminations due seasonal ventilation and a fast growth rate (418 μm/year; Jackson, 2009). These laminations have been sampled at a c.400 μm resolution along the central growth axis. Winter rainfall amount in the region surrounding La Garma cave has been shown to be sensitive to the state of the NAO - with a Spearman rank correlation coefficient of ρ = 0.28 (54 years; p < 0.05) - consistent with the isotope results for GAR-02: maxima in speleothem GAR-02 δ18O coincide with positive phases of the NAO. Several studies have now reconstructed the NAO index using different proxies (e.g. speleothem lamina thickness, tree-ring widths, Sr/Ca ratio from corals). These proxies are correlated to the instrumental NAO coefficients that range between -0.25 (Proctor et al., 2000) and 0.15 (Goodkin et al., 2008). After applying a running mean of 3/5years, δ18O in the new GAR-02 speleothem record is significantly correlated with the instrumental NAO (ρ = 0.16/0.28) indicating the potential for speleothem δ18O as an indicator of past NAO states during the last millennium.

  9. 26 CFR 31.6011(a)-6 - Final returns.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...—(i) Form CT-1. An employer required to make returns on Form CT-1 who in any return period ceases to pay taxable compensation shall make the return on Form CT-1 for such period as a final return. Such... ceased to pay taxable compensation shall continue to file returns on Form CT-1. (ii) Form CT-2....

  10. Tatanka Returns.

    ERIC Educational Resources Information Center

    Simonelli, Richard

    1993-01-01

    Describes efforts of the InterTribal Bison Cooperative (Rapid City, SD) to reintroduce the buffalo for cultural purposes to American Indian reservations. Explains how the buffalo's return is contributing to community wellness. Discusses career opportunities for both Native and non-Native people in buffalo management. (LP)

  11. A 1000-year record of dry conditions in the eastern Canadian prairies reconstructed from oxygen and carbon isotope measurements on Lake Winnipeg sediment organics

    USGS Publications Warehouse

    Buhay, W.M.; Simpson, S.; Thorleifson, H.; Lewis, M.; King, J.; Telka, A.; Wilkinson, Philip M.; Babb, J.; Timsic, S.; Bailey, D.

    2009-01-01

    A short sediment core (162 cm), covering the period AD 920-1999, was sampled from the south basin of Lake Winnipeg for a suite of multi-proxy analyses leading towards a detailed characterisation of the recent millennial lake environment and hydroclimate of southern Manitoba, Canada. Information on the frequency and duration of major dry periods in southern Manitoba, in light of the changes that are likely to occur as a result of an increasingly warming atmosphere, is of specific interest in this study. Intervals of relatively enriched lake sediment cellulose oxygen isotope values (??18Ocellulose) were found to occur from AD 1180 to 1230 (error range: AD 1104-1231 to 1160-1280), 1610-1640 (error range: AD 1571-1634 to 1603-1662), 1670-1720 (error range: AD 1643-1697 to 1692-1738) and 1750-1780 (error range: AD 1724-1766 to 1756-1794). Regional water balance, inferred from calculated Lake Winnipeg water oxygen isotope values (??18Oinf-lw), suggest that the ratio of lake evaporation to catchment input may have been 25-40% higher during these isotopically distinct periods. Associated with the enriched d??18Ocellulose intervals are some depleted carbon isotope values associated with more abundantly preserved sediment organic matter (d??13COM). These suggest reduced microbial oxidation of terrestrially derived organic matter and/or subdued lake productivity during periods of minimised input of nutrients from the catchment area. With reference to other corroborating evidence, it is suggested that the AD 1180-1230, 1610-1640, 1670-1720 and 1750-1780 intervals represent four distinctly drier periods (droughts) in southern Manitoba, Canada. Additionally, lower-magnitude and duration dry periods may have also occurred from 1320 to 1340 (error range: AD 1257-1363), 1530-1540 (error range: AD 1490-1565 to 1498-1572) and 1570-1580 (error range: AD 1531-1599 to 1539-1606). ?? 2009 John Wiley & Sons, Ltd.

  12. A 1000-year sediment record of recurring hypoxia off the Mississippi River: The potential role of terrestrially-derived organic matter inputs

    USGS Publications Warehouse

    Swarzenski, P.W.; Campbell, P.L.; Osterman, L.E.; Poore, R.Z.

    2008-01-01

    A suite of inorganic and organic geochemical tracers and a low-oxygen tolerant benthic faunal index ('PEB') were measured in a 14C-dated 2+??m long gravity core collected on the Louisiana shelf adjacent to the Mississippi River delta to study potential millennium-scale low-oxygen events. Periodic down-core excursions in the PEB index throughout the core suggest recurring, natural bottom water low-oxygen events that extend back ??? 1000??14C years. Select trace element and biomarker distributions in these same sediments were examined as potential tracers of past hypoxic events and to help distinguish between marine versus terrestrial processes involved in organic carbon production. In discrete sediment horizons where the PEB index was elevated, redox-sensitive vanadium concentrations were consistently depleted, excursions in sedimentary ??13C suggest periodic, preferential terrestrial inputs, and the concentrations of two sterol biomarkers (sitosterol and ??-stigmasterol) also showed concurrent enrichments. If the PEB index successfully records ??? 1000??14C year-scale low-oxygen events, then the distribution of these geochemical tracers can be interpreted to corroborate the view that naturally occurring low-oxygen bottom water conditions have existed on the inner Louisiana continental shelf, not only in recent times, but also over at least the last 1000??14C years. These data support the general hypothesis that historic, low-oxygen bottom water conditions on the Louisiana shelf are likely tied to periods of increased fluvial discharge and associated wetland export in the absence of modern river levees. Enhanced river discharge and associated material export would both stimulate enhanced in situ organic carbon production and foster water column stratification. Such periodic elevated river flows during the last millennium can be linked to climate fluctuations and tropical storm activity. ?? 2008 Elsevier B.V. All rights reserved.

  13. [The campaign of returning to the ancient in sphygmology in the Republican Period as viewed from Mai xue cong shu (Series of Pulse Taking)].

    PubMed

    Han, Sujie; Hu, Xiaofeng

    2015-01-01

    From the Southern and Northern Dynasties to the beginning of the Northern Song Dynasty, the models of "master and apprentice" and "physician of long family tradition for generations" were the main ways for teaching medical knowledge. With the rapid amassment of medical books in the Due to the rapid transmission of western science and technology into China in the Republican period, the art of pulse taking had been treated as unscientific. Yao Xinyuan advocated the recovery of ancient pulse taking of the three-portion approach, i.e., taking the pulses at the neck, hands, and feet for comparison. To spread this idea, Yao and Zhang Ziying compiled the Mai xue cong shu (Series of Pulse Taking) in 1937-1947. Altogether 4 issues were published carrying 29 articles concerning the theoretical exploration, experimental research, and clinical practice. Their thinking and approaches were influential to the study and development of modern sphygmology. PMID:26268252

  14. A Millennial Simulation of Isotope-Enable GCM with a Special Focus on Antarctic Climate Variability in the Past 1,000 Years

    NASA Astrophysics Data System (ADS)

    Ding, Q.; Steig, E. J.; Werner, M.

    2015-12-01

    Our knowledge of changes in Southern Hemisphere (SH) circulation during the last millennium is extremely limited in comparison to the Northern Hemisphere (NH) because of the low density of proxy records in the SH. This period provides a good opportunity for placing the recent and twentieth-century SH circulation change into a longer term context and examining the effect of both the anthropogenic and natural external forces on SH circulation. The instrumental data in the SH can provide only at most 100 years of climate information back to the early twentieth century. Thus, we have to rely on various paleoclimate proxy data to evaluate the model's millennial simulation. Several scientific works have pointed out the existence of climate changes in Antarctica, Australia, New Zealand, and South America and their relationships to the Medieval Warm Period (MWP) and Little Ice Age (LIA). There is an advantage to directly comparing model-generated δ18O and observed δ18O in the ice core. However, the models used to produce the millennial simulations in the AR5 and most model comparison projects do not have the ability to produce water isotopes. So a direct comparison between ice-core data and the millennial simulations is impossible. To fill this gap, we take a new approach to generate an Antarctica-wide δ18O field associate with each millennial run. Using the 100 to 200 year climatology of SSTs and sea-ice conditions during three key periods—MWP (1000-1200), LIA (1500-1700), and PWP (1850-present)—generated by existing millennial run to force our isotope GCM model. To better include the meteorological information in our new experiment, corresponding atmospheric states (U, V and T) for each period could also be retrieved from these existing runs, and the atmospheric field of our isotope-enable GCM can be nudged onto this meteorological pattern. Through this method, we can roughly produce a virtual δ18O pattern in Antarctica for each millennial run, which allows us to

  15. The Point of No Return

    PubMed Central

    Logan, Gordon D.

    2015-01-01

    Bartlett (1958) described the point of no return as a point of irrevocable commitment to action, which was preceded by a period of gradually increasing commitment. As such, the point of no return reflects a fundamental limit on the ability to control thought and action. I review the literature on the point of no return, taking three perspectives. First, I consider the point of no return from the perspective of the controlled act, as a locus in the architecture and anatomy of the underlying processes. I review experiments from the stop-signal paradigm that suggest that the point of no return is located late in the response system. Then I consider the point of no return from the perspective of the act of control that tries to change the controlled act before it becomes irrevocable. From this perspective, the point of no return is a point in time that provides enough “lead time” for the act of control to take effect. I review experiments that measure the response time to the stop signal as the lead time required for response inhibition in the stop-signal paradigm. Finally, I consider the point of no return in hierarchically controlled tasks, in which there may be many points of no return at different levels of the hierarchy. I review experiments on skilled typing that suggest different points of no return for the commands that determine what is typed and the countermands that inhibit typing, with increasing commitment to action the lower the level in the hierarchy. I end by considering the point of no return in perception and thought as well as action. PMID:25633089

  16. Estimation of return periods for extreme sea levels: a simplified empirical correction of the joint probabilities method with examples from the French Atlantic coast and three ports in the southwest of the UK

    NASA Astrophysics Data System (ADS)

    Pirazzoli, Paolo Antonio; Tomasin, Alberto

    2007-04-01

    The joint probability method (JPM) to estimate the probability of extreme sea levels (Pugh and Vassie, Extreme sea-levels from tide and surge probability. Proc. 16th Coastal Engineering Conference, 1978, Hamburg, American Society of Civil Engineers, New York, pp 911 930, 1979) has been applied to the hourly records of 13 tide-gauge stations of the tidally dominated Atlantic coast of France (including Brest, since 1860) and to three stations in the southwest of the UK (including Newlyn, since 1916). The cumulative total length of the available records (more than 426 years) is variable from 1 to 130 years when individual stations are considered. It appears that heights estimated with the JPM are almost systematically greater than the extreme heights recorded. Statistical analysis shows that this could be due: (1) to surge tide interaction (that may tend to damp surge values that occur at the time of the highest tide levels), and (2) to the fact that major surges often occur in seasonal periods that may not correspond to those of extreme astronomical tides. We have determined at each station empirical ad hoc correction coefficients that take into account the above two factors separately, or together, and estimated return periods for extreme water levels also at stations where only short records are available. For seven long records, for which estimations with other computing methods (e.g. generalized extreme value [GEV] distribution and Gumbel) can be attempted, average estimations of extreme values appear slightly overestimated in relation to the actual maximum records by the uncorrected JPM (+16.7 ± 7.2 cm), and by the Gumbel method alone (+10.3 ± 6.3 cm), but appear closer to the reality with the GEV distribution (-2.0 ± 5.3 cm) and with the best-fitting correction to the JPM (+2.9 ± 4.4 cm). Because the GEV analysis can hardly be extended to short records, it is proposed to apply at each station, especially for short records, the JPM and the site-dependent ad

  17. 76 FR 14827 - Disclosure of Returns and Return Information to Designee of Taxpayer

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-18

    ... Internal Revenue Service 26 CFR Part 301 RIN 1545-BJ19 Disclosure of Returns and Return Information to Designee of Taxpayer AGENCY: Internal Revenue Service (IRS), Treasury. ACTION: Notice of proposed... the period for submission to the IRS of taxpayer authorizations permitting disclosure of returns...

  18. Why Do Staff Return?

    ERIC Educational Resources Information Center

    Magnuson, Connie

    1992-01-01

    Surveyed 211 returning staff from 25 camps and interviewed 19 returning staff to study factors that influence a counselor's decision to return to camp. Examined the following dimensions of motivation and hygiene factors: (1) stimulation or inspiration; (2) personal; (3) job-related experience; (4) living conditions and camp life; (5) camp…

  19. 26 CFR 31.6011(a)-5 - Monthly returns.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... IRS shall make a return for the calendar month in which the notice is received, for each of the prior calendar months in the return period, and for each calendar month afterwards (whether or not wages are paid in any such month) until the employer has filed a final return or is required to make quarterly...

  20. 26 CFR 31.6011(a)-5 - Monthly returns.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... IRS shall make a return for the calendar month in which the notice is received, for each of the prior calendar months in the return period, and for each calendar month afterwards (whether or not wages are paid in any such month) until the employer has filed a final return or is required to make quarterly...

  1. 26 CFR 31.6011(a)-5 - Monthly returns.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... IRS shall make a return for the calendar month in which the notice is received, for each of the prior calendar months in the return period, and for each calendar month afterwards (whether or not wages are paid in any such month) until the employer has filed a final return or is required to make quarterly...

  2. 26 CFR 31.6011(a)-5 - Monthly returns.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... IRS shall make a return for the calendar month in which the notice is received, for each of the prior calendar months in the return period, and for each calendar month afterwards (whether or not wages are paid in any such month) until the employer has filed a final return or is required to make quarterly...

  3. 26 CFR 31.6011(a)-5 - Monthly returns.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... IRS shall make a return for the calendar month in which the notice is received, for each of the prior calendar months in the return period, and for each calendar month afterwards (whether or not wages are paid in any such month) until the employer has filed a final return or is required to make quarterly...

  4. Returning Samples from Enceladus

    NASA Astrophysics Data System (ADS)

    Tsou, P.; Kanik, I.; Brownlee, D.; McKay, C.; Anbar, A.; Glavin, D.; Yano, H.

    2012-12-01

    search for chemical biosignatures to understand the habitability potential of the subsurface ocean of Enceladus [Glavin et al. 2011]. By assessing the chiral excess among different amino acids, identifying chains of amino acids, isolate distinct sequences of these chains and the same for nucleic acids, we can formulate a new set of hypotheses to address some of the key science questions required for investigating the stage of extraterrestrial life at Enceladus beyond the four factors of habitability. Criticality of Analyses - For extraterrestrial organic matter analyses such as chirality and compound-specific isotopes, the repeatable robustness of laboratory measurements is a necessity. These analyses require a series of chemical extraction and derivatization steps prior to analysis that is adapted to the sample and procedures results-driven. The Stardust mission is an excellent example of the challenges in the analysis of organics. Confirmation of the cometary origin of the amino acid glycine from comet Wild 2 was obtained 3 years after the samples were returned to Earth. This long period of laboratory development allowed several modifications to the extraction protocol, multiple analytical techniques and instrumentations. Reference: Tsou et al., Astrobiology, in press 2012. McKay et al. Astrobiology 2008. Waite et al. Nature V 460 I 7254, 2009. Postberg et al. EPSC 642P 2011. Glavin et al., LPSC, #5002, 2011.

  5. Return flux experiment

    NASA Technical Reports Server (NTRS)

    Tveekrem, June L.

    1992-01-01

    All spacecraft emit molecules via outgassing, thruster plumes, vents, etc. The return flux is the portion of those molecules that scatter from the ambient atmosphere and return to the spacecraft. Return flux allows critical spacecraft surfaces to become contaminated even when there is no direct line of sight between the contamination source and the critical surface. Data from the Long Duration Exposure Facility (LDEF) show that contamination of LDEF surfaces could not have come entirely from direct flux. The data suggest significant return flux. Several computer models have been developed to simulate return flux, but the predictions have never been verified in orbit. Large uncertainties in predictions lead to overly conservative spacecraft designs. The purpose of the REturn FLux EXperiment (REFLEX) is to fly a controlled experiment that can be directly compared with predictions from several models.

  6. Assured crew return vehicle

    NASA Technical Reports Server (NTRS)

    Cerimele, Christopher J. (Inventor); Ried, Robert C. (Inventor); Peterson, Wayne L. (Inventor); Zupp, George A., Jr. (Inventor); Stagnaro, Michael J. (Inventor); Ross, Brian P. (Inventor)

    1991-01-01

    A return vehicle is disclosed for use in returning a crew to Earth from low earth orbit in a safe and relatively cost effective manner. The return vehicle comprises a cylindrically-shaped crew compartment attached to the large diameter of a conical heat shield having a spherically rounded nose. On-board inertial navigation and cold gas control systems are used together with a de-orbit propulsion system to effect a landing near a preferred site on the surface of the Earth. State vectors and attitude data are loaded from the attached orbiting craft just prior to separation of the return vehicle.

  7. Lightning return stroke models

    NASA Technical Reports Server (NTRS)

    Lin, Y. T.; Uman, M. A.; Standler, R. B.

    1980-01-01

    We test the two most commonly used lightning return stroke models, Bruce-Golde and transmission line, against subsequent stroke electric and magnetic field wave forms measured simultaneously at near and distant stations and show that these models are inadequate to describe the experimental data. We then propose a new return stroke model that is physically plausible and that yields good approximations to the measured two-station fields. Using the new model, we derive return stroke charge and current statistics for about 100 subsequent strokes.

  8. Return to Bangka Island.

    PubMed

    Spence, J

    2001-07-01

    This article is a return in a couple of ways to one of the most tragic events in the history of Australian military nursing. Firstly, it describes how the evacuation of nurses from Singapore in 1941 led to circumstances that resulted in the massacre or internment of many of those women. Then in 1993, a group of surviving World War II nurses and current serving Australian Army nurses returned to the site of their sorrow. PMID:15129536

  9. Comet nucleus and asteroid sample return missions

    NASA Astrophysics Data System (ADS)

    Melton, Robert G.; Thompson, Roger C.; Starchville, Thomas F., Jr.; Adams, C.; Aldo, A.; Dobson, K.; Flotta, C.; Gagliardino, J.; Lear, M.; McMillan, C.

    During the 1991-92 academic year, the Pennsylvania State University has developed three sample return missions: one to the nucleus of comet Wild 2, one to the asteroid Eros, and one to three asteroids located in the Main Belt. The primary objective of the comet nucleus sample return mission is to rendezvous with a short period comet and acquire a 10 kg sample for return to Earth. Upon rendezvous with the comet, a tethered coring and sampler drill will contact the surface and extract a two-meter core sample from the target site. Before the spacecraft returns to Earth, a monitoring penetrator containing scientific instruments will be deployed for gathering long-term data about the comet. A single asteroid sample return mission to the asteroid 433 Eros (chosen for proximity and launch opportunities) will extract a sample from the asteroid surface for return to Earth. To limit overall mission cost, most of the mission design uses current technologies, except the sampler drill design. The multiple asteroid sample return mission could best be characterized through its use of future technology including an optical communications system, a nuclear power reactor, and a low-thrust propulsion system. A low-thrust trajectory optimization code (QuickTop 2) obtained from the NASA LeRC helped in planning the size of major subsystem components, as well as the trajectory between targets.

  10. Comet nucleus and asteroid sample return missions

    NASA Technical Reports Server (NTRS)

    Melton, Robert G.; Thompson, Roger C.; Starchville, Thomas F., Jr.; Adams, C.; Aldo, A.; Dobson, K.; Flotta, C.; Gagliardino, J.; Lear, M.; Mcmillan, C.

    1992-01-01

    During the 1991-92 academic year, the Pennsylvania State University has developed three sample return missions: one to the nucleus of comet Wild 2, one to the asteroid Eros, and one to three asteroids located in the Main Belt. The primary objective of the comet nucleus sample return mission is to rendezvous with a short period comet and acquire a 10 kg sample for return to Earth. Upon rendezvous with the comet, a tethered coring and sampler drill will contact the surface and extract a two-meter core sample from the target site. Before the spacecraft returns to Earth, a monitoring penetrator containing scientific instruments will be deployed for gathering long-term data about the comet. A single asteroid sample return mission to the asteroid 433 Eros (chosen for proximity and launch opportunities) will extract a sample from the asteroid surface for return to Earth. To limit overall mission cost, most of the mission design uses current technologies, except the sampler drill design. The multiple asteroid sample return mission could best be characterized through its use of future technology including an optical communications system, a nuclear power reactor, and a low-thrust propulsion system. A low-thrust trajectory optimization code (QuickTop 2) obtained from the NASA LeRC helped in planning the size of major subsystem components, as well as the trajectory between targets.

  11. Returning to School for Higher Returns

    ERIC Educational Resources Information Center

    Park, Seonyoung

    2011-01-01

    On the basis of those respondents in the National Longitudinal Survey of Youth (NLSY) who change jobs with an intervening period of education reinvestment, the conventional assumption of linearity of log wages in years of schooling is strongly rejected: a typical reinvestment for the 1980 through 1993 period is associated with a rise of about 3.5…

  12. 26 CFR 1.6081-1 - Extension of time for filing returns.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... return, information return, statement, or other document, including the taxable year or period thereof... of time for filing any return, declaration, statement, or other document which relates to any tax... return of a DISC (as defined in section 992(a)), as specified in section 6072(b), shall not be...

  13. 26 CFR 1.6081-1 - Extension of time for filing returns.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... return, information return, statement, or other document, including the taxable year or period thereof... of time for filing any return, declaration, statement, or other document which relates to any tax... return of a DISC (as defined in section 992(a)), as specified in section 6072(b), shall not be...

  14. 26 CFR 1.6081-1 - Extension of time for filing returns.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... return, information return, statement, or other document, including the taxable year or period thereof... of time for filing any return, declaration, statement, or other document which relates to any tax... return of a DISC (as defined in section 992(a)), as specified in section 6072(b), shall not be...

  15. 26 CFR 1.6081-1 - Extension of time for filing returns.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... return, information return, statement, or other document, including the taxable year or period thereof... of time for filing any return, declaration, statement, or other document which relates to any tax... return of a DISC (as defined in section 992(a)), as specified in section 6072(b), shall not be...

  16. [Fever in returning travelers].

    PubMed

    Burchard, G

    2014-03-01

    Travel-related illness is most often due to gastrointestinal, febrile, and dermatologic diseases. Fever in a returned traveler demands prompt attention because it may be a manifestation of an infection that could be rapidly progressive and lethal. The approach to the febrile patient should be stepwise and consider travel and exposure history. Malaria is the most common cause of fever in patients returning from Sub-Saharan Africa, whereas dengue is more frequent in travelers from other tropical and subtropical areas. Other serious diseases are typhoid and paratyphoid fever, amebic liver abscess, visceral leishmaniasis, leptospirosis and-rarely-viral hemorrhagic fevers. PMID:24557143

  17. Electrostatic Return of Contaminants

    NASA Technical Reports Server (NTRS)

    Rantanen, R.; Gordon, T.

    2003-01-01

    A Model has been developed capable of calculating the electrostatic return of spacecraft-emitted molecules that are ionized and attracted back to the spacecraft by the spacecraft electric potential on its surfaces. The return of ionized contaminant molecules to charged spacecraft surfaces is very important to all altitudes. It is especially important at geosynchronous and interplanetary environments, since it may be the only mechanism by which contaminants can degrade a surface. This model is applicable to all altitudes and spacecraft geometries. In addition to results of the model will be completed to cover a wide range of potential space systems.

  18. Volatility return intervals analysis of the Japanese market

    NASA Astrophysics Data System (ADS)

    Jung, W.-S.; Wang, F. Z.; Havlin, S.; Kaizoji, T.; Moon, H.-T.; Stanley, H. E.

    2008-03-01

    We investigate scaling and memory effects in return intervals between price volatilities above a certain threshold q for the Japanese stock market using daily and intraday data sets. We find that the distribution of return intervals can be approximated by a scaling function that depends only on the ratio between the return interval τ and its mean <τ>. We also find memory effects such that a large (or small) return interval follows a large (or small) interval by investigating the conditional distribution and mean return interval. The results are similar to previous studies of other markets and indicate that similar statistical features appear in different financial markets. We also compare our results between the period before and after the big crash at the end of 1989. We find that scaling and memory effects of the return intervals show similar features although the statistical properties of the returns are different.

  19. Sustainable Mars Sample Return

    NASA Technical Reports Server (NTRS)

    Alston, Christie; Hancock, Sean; Laub, Joshua; Perry, Christopher; Ash, Robert

    2011-01-01

    The proposed Mars sample return mission will be completed using natural Martian resources for the majority of its operations. The system uses the following technologies: In-Situ Propellant Production (ISPP), a methane-oxygen propelled Mars Ascent Vehicle (MAV), a carbon dioxide powered hopper, and a hydrogen fueled balloon system (large balloons and small weather balloons). The ISPP system will produce the hydrogen, methane, and oxygen using a Sabatier reactor. a water electrolysis cell, water extracted from the Martian surface, and carbon dioxide extracted from the Martian atmosphere. Indigenous hydrogen will fuel the balloon systems and locally-derived methane and oxygen will fuel the MAV for the return of a 50 kg sample to Earth. The ISPP system will have a production cycle of 800 days and the estimated overall mission length is 1355 days from Earth departure to return to low Earth orbit. Combining these advanced technologies will enable the proposed sample return mission to be executed with reduced initial launch mass and thus be more cost efficient. The successful completion of this mission will serve as the next step in the advancement of Mars exploration technology.

  20. Higher Education Endowments Return

    ERIC Educational Resources Information Center

    Bahlmann, David; Walda, John D.; Sedlacek, Verne O.

    2012-01-01

    A new study of endowments by the National Association of College and University Business Officers (NACUBO) and the Commonfund Institute has brought good news to college and universities: While endowment returns dropped precipitously in fiscal year 2009 as a result of the financial crisis and accompanying slide in equity markets, they climbed to an…

  1. Return to Play

    ERIC Educational Resources Information Center

    Mangan, Marianne

    2013-01-01

    Call it physical activity, call it games, or call it play. Whatever its name, it's a place we all need to return to. In the physical education, recreation, and dance professions, we need to redesign programs to address the need for and want of play that is inherent in all of us.

  2. Phobos Sample Return mission

    NASA Astrophysics Data System (ADS)

    Zelenyi, Lev; Zakharov, A.; Martynov, M.; Polischuk, G.

    Very mysterious objects of the Solar system are the Martian satellites, Phobos and Deimos. Attempt to study Phobos in situ from an orbiter and from landers have been done by the Russian mission FOBOS in 1988. However, due to a malfunction of the onboard control system the landers have not been delivered to the Phobos surface. A new robotics mission to Phobos is under development now in Russia. Its main goal is the delivery of samples of the Phobos surface material to the Earth for laboratory studies of its chemical, isotopic, mineral composition, age etc. Other goals are in situ studies of Phobos (regolith, internal structure, peculiarities in orbital and proper rotation), studies of Martian environment (dust, plasma, fields). The payload includes a number of scientific instruments: gamma and neutron spectrometers, gaschromatograph, mass spectrometers, IR spectrometer, seismometer, panoramic camera, dust sensor, plasma package. To implement the tasks of this mission a cruise-transfer spacecraft after the launch and the Earth-Mars interplanetary flight will be inserted into the first elliptical orbit around Mars, then after several corrections the spacecraft orbit will be formed very close to the Phobos orbit to keep the synchronous orbiting with Phobos. Then the spacecraft will encounter with Phobos and will land at the surface. After the landing the sampling device of the spacecraft will collect several samples of the Phobos regolith and will load these samples into the return capsule mounted at the returned vehicle. This returned vehicle will be launched from the mother spacecraft and after the Mars-Earth interplanetary flight after 11 monthes with reach the terrestrial atmosphere. Before entering into the atmosphere the returned capsule will be separated from the returned vehicle and will hopefully land at the Earth surface. The mother spacecraft at the Phobos surface carrying onboard scientific instruments will implement the "in situ" experiments during an year

  3. Changing Returns to Education in Spain During the 1980s.

    ERIC Educational Resources Information Center

    Vila, Luis-Eduardo; Mora, Jose-Gines

    1998-01-01

    Presents evidence on returns to education for Spanish employees during the 1980s, a period of remarkable structural transformation. Results show a declining payoff to education between 1981 and 1991 for lower and intermediate educational levels. Higher education does not show a reduction in return. Earnings inequality by gender declined noticeably…

  4. 29 CFR 825.311 - Intent to return to work.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Intent to return to work. 825.311 Section 825.311 Labor... AND MEDICAL LEAVE ACT OF 1993 Employee and Employer Rights and Obligations Under the Act § 825.311 Intent to return to work. (a) An employer may require an employee on FMLA leave to report periodically...

  5. Components of multifractality in high-frequency stock returns

    NASA Astrophysics Data System (ADS)

    Kwapień, J.; Oświeçimka, P.; Drożdż, S.

    2005-05-01

    We analyzed multifractal properties of 5-min stock returns from a period of over two years for 100 highly capitalized American companies. The two sources: fat-tailed probability distributions and non-linear temporal correlations, vitally contribute to the observed multifractal dynamics of the returns. For majority of the companies the temporal correlations constitute a much more significant related factor, however.

  6. Assured Crew Return Vehicle

    NASA Technical Reports Server (NTRS)

    Stone, D. A.; Craig, J. W.; Drone, B.; Gerlach, R. H.; Williams, R. J.

    1991-01-01

    The developmental status is discussed regarding the 'lifeboat' vehicle to enhance the safety of the crew on the Space Station Freedom (SSF). NASA's Assured Crew Return Vehicle (ACRV) is intended to provide a means for returning the SSF crew to earth at all times. The 'lifeboat' philosophy is the key to managing the development of the ACRV which further depends on matrixed support and total quality management for implementation. The risk of SSF mission scenarios are related to selected ACRV mission requirements, and the system and vehicle designs are related to these precepts. Four possible ACRV configurations are mentioned including the lifting-body, Apollo shape, Discoverer shape, and a new lift-to-drag concept. The SCRAM design concept is discussed in detail with attention to the 'lifeboat' philosophy and requirements for implementation.

  7. Problem Periods

    MedlinePlus

    ... gov/ Home Body Getting your period Problem periods Problem periods It’s common to have cramps or feel ... doctor Some common period problems Signs of period problems top One way to know if you may ...

  8. Returns to Education in Bangladesh

    ERIC Educational Resources Information Center

    Asadullah, Mohammad Niaz

    2006-01-01

    This paper reports labour market returns to education in Bangladesh using data from recent nationwide household survey. Returns are estimated separately for rural and urban samples, males, females and private-sector employees. Substantial heterogeneity in returns is observed; for example, estimates are higher for urban (than rural sample) and…

  9. Energy Vs. Productivity: Diminishing Returns

    ERIC Educational Resources Information Center

    MOSAIC, 1975

    1975-01-01

    Energy invested in corn production is compared with food energy returned in calculations by David Pimentel at Cornell University. The rate of return is falling off sharply in this already energy-intensive agriculture. Increased energy input, in the form of fertilizer, would yield far greater returns where agriculture is less sophisticated.…

  10. A Look at Returning Teachers

    ERIC Educational Resources Information Center

    DeAngelis, Karen J.

    2013-01-01

    Research shows that one-quarter to one-third of teachers who leave the profession return, the majority after only a short absence. Though returning teachers can constitute a substantial share of newly hired teachers in schools each year, little is known about them, the factors associated with their decisions to return, or the schools to which…

  11. Puerto Rican Return Migrant Youth.

    ERIC Educational Resources Information Center

    Carrasquillo, Angela; Carrasquillo, Ceferino

    Among Puerto Ricans who have migrated to the United States, a significant number have returned to Puerto Rico, while others shuttle between Puerto Rico and the United States. These groups of people are identified as return migrants. Studies suggest that return migrant youth in Puerto Rico have had to make environmental and cultural adjustments…

  12. Sample Return Science

    NASA Astrophysics Data System (ADS)

    Williford, K. H.; Allwood, A.; Beegle, L. W.; Bhartia, R.; Flannery, D.; Hoffmann, A.; Mora, M. F.; Orbay, J.; Petrizzo, D. A.; Tuite, M. L., Jr.; Willis, P. A.

    2014-12-01

    The first clear identification of an ancient habitable environment on Mars by the Mars Science Laboratory (MSL) rover mission relied on a synthetic analytical approach combining orbital and surface imagery and spectroscopy with sophisticated sample acquisition and handling technology including a rotary percussive drill that provided powdered rock for bulk geochemical analysis [1]. The recent announcement of the instrument package for the proposed NASA Mars2020 rover mission, including micro x-ray fluorescence (PIXL) for elemental mapping as well as scanning ultraviolet laser fluorescence and Raman (SHERLOC) suggests a shift in emphasis of Mars surface science towards spatially resolved geochemical analysis that will support the selection and acquisition of samples for coring, caching, and possible return to Earth for further analysis. During a recent field expedition to investigate Archean and Proterozoic biosignatures in the Pilbara region of Western Australia, we deployed a dry, rotary percussive coring drill with a bit assembly analogous to that being considered for Mars2020. Six targets of varying age and lithology were sampled with the coring drill, and surrounding and adjacent rock samples were collected simultaneously. These samples were subsequently prepared and subsampled for bulk and in situ, spatially resolved analysis using conventional laboratory methods as well as the existing PIXL and SHERLOC platforms currently in development. Here we present new approaches and data from this integrated and ongoing program of "sample return science" designed to simulate, and eventually reduce risk associated with a long-term effort towards Mars sample return. [1] Grotzinger, J.P. et al. 2014. Science 343 DOI: 10.1126/science.1242777.

  13. Mars sample return - Science

    NASA Technical Reports Server (NTRS)

    Blanchard, Douglas P.

    1988-01-01

    The possible scientific goals of a Mars sample return mission are reviewed, including the value of samples and the selection of sampling sites. The fundamental questions about Mars which could be studied using samples are examined, including planetary formation, differentiation, volcanism and petrogenesis, weathering, and erosion. Scenarios are presented for sample acquisition and analysis. Possible sampling methods and tools are discussed, including drilling techniques, types of rovers, and processing instruments. In addition, the possibility of aerocapture out of elliptical or circular orbit is considered.

  14. Titan Science Return Quantification

    NASA Technical Reports Server (NTRS)

    Weisbin, Charles R.; Lincoln, William

    2014-01-01

    Each proposal for a NASA mission concept includes a Science Traceability Matrix (STM), intended to show that what is being proposed would contribute to satisfying one or more of the agency's top-level science goals. But the information traditionally provided cannot be used directly to quantitatively compare anticipated science return. We added numerical elements to NASA's STM and developed a software tool to process the data. We then applied this methodology to evaluate a group of competing concepts for a proposed mission to Saturn's moon, Titan.

  15. The Chilean strawberry (Fragaria chiloensis): Over 1000 years of domestication

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The cultivated strawberry of South America, Fragaria chiloensis, has a long history. At least two native peoples, the Mapuche and the Picunche began the domestication process. While white- and red-fruited forms were domesticated, the white form was preferred as the red-fruited types are not mention...

  16. Gulf of Mexico dead zone - 1000 year record

    USGS Publications Warehouse

    Osterman, L.E.; Poore, R.Z.; Swarzenski, P.W.

    2010-01-01

    An area of oxygen-depleted bottom- and subsurfacewater (hypoxia = dissolved oxygen Since systematic measurement of the extent of the dead zone was begun in 1985, the overall pattern indicates that the area of the dead zone is increasing. Several studies have concluded that the expansion of the Louisiana shelf dead zone is related to increased nutrients (primarily nitrogen, but possibly also phosphorous) in the Mississippi River drainage basin and is responsible for the degradation of Gulf of Mexico marine habitats. The goal of this research is to augment information on the recent expansion of Louisiana shelf hypoxia and to investigate the temporal and geographic extent of the lowoxygen bottom-water conditions prior to 1985 in sediment cores collected from the Louisiana shelf. We use a specific low-oxygen faunal proxy termed the PEB index based on the cumulative percentage of three foraminifers (= % Protononion atlanticum, + % Epistominella vitrea, + % Buliminella morgani) that has been shown statistically to represent the modern seasonal Louisiana hypoxia zone. Our hypothesis is that the increased relative abundance of PEB species in dated sediment cores accurately tracks past seasonal low-oxygen conditions on the Louisiana shelf.

  17. Major coastal impact induced by a 1000-year storm event

    PubMed Central

    Fruergaard, Mikkel; Andersen, Thorbjørn J.; Johannessen, Peter N.; Nielsen, Lars H.; Pejrup, Morten

    2013-01-01

    Extreme storms and storm surges may induce major changes along sandy barrier coastlines, potentially causing substantial environmental and economic damage. We show that the most destructive storm (the 1634 AD storm) documented for the northern Wadden Sea within the last thousand years both caused permanent barrier breaching and initiated accumulation of up to several metres of marine sand. An aggradational storm shoal and a prograding shoreface sand unit having thicknesses of up to 8 m and 5 m respectively were deposited as a result of the storm and during the subsequent 30 to 40 years long healing phase, on the eroded shoreface. Our results demonstrate that millennial-scale storms can induce large-scale and long-term changes on barrier coastlines and shorefaces, and that coastal changes assumed to take place over centuries or even millennia may occur in association with and be triggered by a single extreme storm event.

  18. Return to Space

    NASA Technical Reports Server (NTRS)

    1989-01-01

    This video documents the preparations for Shuttle Flight STS-26 with Shuttle Discovery, NASA's return to manned space flight after the Challenger disaster. Footage and descriptions document such changes to the new Shuttle as new joints, improved insulation, and added O-rings to the solid rocket boosters; new safety hardware and procedures such as parachute and sidewire evacuations during liftoff, and new pressure suits; modified landing gear, brakes, and nose wheel steering, as well as a modified landing runway. Also profiled are the 5 member crew of all veteran Shuttle astronauts, the TDRS 3 Satellite to be released from the cargo bay in orbit, and 11 commercial and student experiments to be performed during the mission.

  19. Dealing with returned manuscripts.

    PubMed

    Peh, W C G; Ng, K H

    2009-11-01

    It is useful for authors to learn to deal with returned manuscripts with a rejection decision or a request for revision. Common reasons for rejection include contents outside the scope of the journal or inappropriate for the journal, incomplete submission, poor methodology, faulty experimental design, major flaws in the interpretation of results, extremely poor writing, and duplicated or plagiarised work. Authors should use the editor's and reviewers' comments to improve their manuscripts and resubmit elsewhere. Common reasons for revision requests include minor faults in the methodology, minor inaccuracies in data, inconsistencies among different sections of the manuscript, faulty deductions, data that do not support the conclusions, excessive data or text, poor or excessive illustrations, and poor but salvageable writing. A request for revision should be viewed positively, as it means that there is a possibility that the manuscript may still be potentially publishable, provided that all the editor's and reviewers' comments are addressed. PMID:19960157

  20. Return to space

    NASA Astrophysics Data System (ADS)

    1989-08-01

    This video documents the preparations for Shuttle Flight STS-26 with Shuttle Discovery, NASA's return to manned space flight after the Challenger disaster. Footage and descriptions document such changes to the new Shuttle as new joints, improved insulation, and added O-rings to the solid rocket boosters; new safety hardware and procedures such as parachute and sidewire evacuations during liftoff, and new pressure suits; modified landing gear, brakes, and nose wheel steering, as well as a modified landing runway. Also profiled are the 5 member crew of all veteran Shuttle astronauts, the TDRS 3 Satellite to be released from the cargo bay in orbit, and 11 commercial and student experiments to be performed during the mission.

  1. Returns on Investment in California County Departments of Public Health

    PubMed Central

    2016-01-01

    Objectives. To estimate the average return on investment for the overall activities of county departments of public health in California. Methods. I gathered the elements necessary to estimate the average return on investment for county departments of public health in California during the period 2001 to 2008–2009. These came from peer-reviewed journal articles published as part of a larger project to develop a method for determining return on investment for public health by using a health economics framework. I combined these elements by using the standard formula for computing return on investment, and performed a sensitivity analysis. Then I compared the return on investment for county departments of public health with the returns on investment generated for various aspects of medical care. Results. The estimated return on investment from $1 invested in county departments of public health in California ranges from $67.07 to $88.21. Conclusions. The very large estimated return on investment for California county departments of public health relative to the return on investment for selected aspects of medical care suggests that public health is a wise investment. PMID:27310339

  2. 5 CFR 353.205 - Return to duty and application for reemployment.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Return to duty and application for... Return to duty and application for reemployment. Periods allowed for return to duty are based on the... to determine fitness for the uniformed services, is required to report back to work not later...

  3. 26 CFR 31.6071(a)-1 - Time for filing returns and other documents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) Information returns—(i) General rule. Each information return in respect of wages as defined in the Federal...)-5(a) is filed as a final return for a period ending prior to December 31, the information statement... return required to be made under §§ 31.6011(a)-1 and 31.6011(a)-1T, in respect of the taxes imposed...

  4. Multivariate models of adult Pacific salmon returns.

    PubMed

    Burke, Brian J; Peterson, William T; Beckman, Brian R; Morgan, Cheryl; Daly, Elizabeth A; Litz, Marisa

    2013-01-01

    Most modeling and statistical approaches encourage simplicity, yet ecological processes are often complex, as they are influenced by numerous dynamic environmental and biological factors. Pacific salmon abundance has been highly variable over the last few decades and most forecasting models have proven inadequate, primarily because of a lack of understanding of the processes affecting variability in survival. Better methods and data for predicting the abundance of returning adults are therefore required to effectively manage the species. We combined 31 distinct indicators of the marine environment collected over an 11-year period into a multivariate analysis to summarize and predict adult spring Chinook salmon returns to the Columbia River in 2012. In addition to forecasts, this tool quantifies the strength of the relationship between various ecological indicators and salmon returns, allowing interpretation of ecosystem processes. The relative importance of indicators varied, but a few trends emerged. Adult returns of spring Chinook salmon were best described using indicators of bottom-up ecological processes such as composition and abundance of zooplankton and fish prey as well as measures of individual fish, such as growth and condition. Local indicators of temperature or coastal upwelling did not contribute as much as large-scale indicators of temperature variability, matching the spatial scale over which salmon spend the majority of their ocean residence. Results suggest that effective management of Pacific salmon requires multiple types of data and that no single indicator can represent the complex early-ocean ecology of salmon. PMID:23326586

  5. Return Migration to Mexico: Does Health Matter?

    PubMed

    Arenas, Erika; Goldman, Noreen; Pebley, Anne R; Teruel, Graciela

    2015-12-01

    We use data from three rounds of the Mexican Family Life Survey to examine whether migrants in the United States returning to Mexico in the period 2005-2012 have worse health than those remaining in the United States. Despite extensive interest by demographers in health-related selection, this has been a neglected area of study in the literature on U.S.-Mexico migration, and the few results to date have been contradictory and inconclusive. Using five self-reported health variables collected while migrants resided in the United States and subsequent migration history, we find direct evidence of higher probabilities of return migration for Mexican migrants in poor health as well as lower probabilities of return for migrants with improving health. These findings are robust to the inclusion of potential confounders reflecting the migrants' demographic characteristics, economic situation, family ties, and origin and destination characteristics. We anticipate that in the coming decade, health may become an even more salient issue in migrants' decisions about returning to Mexico, given the recent expansion in access to health insurance in Mexico. PMID:26385111

  6. Multivariate Models of Adult Pacific Salmon Returns

    PubMed Central

    Burke, Brian J.; Peterson, William T.; Beckman, Brian R.; Morgan, Cheryl; Daly, Elizabeth A.; Litz, Marisa

    2013-01-01

    Most modeling and statistical approaches encourage simplicity, yet ecological processes are often complex, as they are influenced by numerous dynamic environmental and biological factors. Pacific salmon abundance has been highly variable over the last few decades and most forecasting models have proven inadequate, primarily because of a lack of understanding of the processes affecting variability in survival. Better methods and data for predicting the abundance of returning adults are therefore required to effectively manage the species. We combined 31 distinct indicators of the marine environment collected over an 11-year period into a multivariate analysis to summarize and predict adult spring Chinook salmon returns to the Columbia River in 2012. In addition to forecasts, this tool quantifies the strength of the relationship between various ecological indicators and salmon returns, allowing interpretation of ecosystem processes. The relative importance of indicators varied, but a few trends emerged. Adult returns of spring Chinook salmon were best described using indicators of bottom-up ecological processes such as composition and abundance of zooplankton and fish prey as well as measures of individual fish, such as growth and condition. Local indicators of temperature or coastal upwelling did not contribute as much as large-scale indicators of temperature variability, matching the spatial scale over which salmon spend the majority of their ocean residence. Results suggest that effective management of Pacific salmon requires multiple types of data and that no single indicator can represent the complex early-ocean ecology of salmon. PMID:23326586

  7. 11. VIEW OF A SITE RETURN WEAPONS COMPONENT. SITE RETURNS ...

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

    11. VIEW OF A SITE RETURN WEAPONS COMPONENT. SITE RETURNS WERE NUCLEAR WEAPONS SHIPPED TO THE ROCKY FLATS PLANT FROM THE NUCLEAR WEAPON STOCKPILE FOR RETIREMENT, TESTING, OR UPGRADING. FISSILE MATERIALS (PLUTONIUM, URANIUM, ETC.) AND RARE MATERIALS (BERYLLIUM) WERE RECOVERED FOR REUSE, AND THE REMAINDER WAS DISPOSED. (8/7/62) - Rocky Flats Plant, Plutonium Fabrication, Central section of Plant, Golden, Jefferson County, CO

  8. Changes in Returns to Education in India, 1983-94: By Gender, Age-Cohort and Location. Center Discussion Paper.

    ERIC Educational Resources Information Center

    Duraisamy, P.

    There is hardly any estimate of returns to schooling in India based on national level representative data for the recent period. This paper provides estimates of the economic returns to education in India by gender, age cohort, and location (by rural-urban) for the most recent period 1993-94, and also evaluates the changes in returns over a period…

  9. Christmas Island birds returning

    NASA Astrophysics Data System (ADS)

    Six months after their mass exodus, birds are beginning to return to Christmas Island. Roughly 17 million birds, almost the entire adult bird population, either perished or fled their mid-Pacific atoll home last autumn, leaving behind thousands of nestlings to starve (Eos, April 5, 1983, p. 131). It is believed that the strong El Niño altered the ecology of the surrounding waters and forced the birds to flee. Christmas Island is the world's largest coral atoll.“Ocean and atmosphere scientists are unsure of future directions for the El Niño conditions and cannot now predict what will happen to the birds in the coming months,” said Ralph W. Schreiber, curator of ornithology at the Natural History Museum of Los Angeles County in California. Heisthe ornithologist who discovered the disappearance. “The recovery of the bird populations depends on the food supply in the waters surrounding the island.” The island's birds feed exclusively on small fish and squid.

  10. Return to sport after arthroscopic meniscectomy on stable knees

    PubMed Central

    2013-01-01

    Background Athletes suffering from any injuries want to know when they will be able to return sports activity. The period of return-to-sport after the arthroscopic meniscectomy is still unknown. The aim of this study is to investigate the period of the return-to-sport from surgery and the clinical symptoms after the meniscectomy on stable knees. Methods Fifty-six athletes who underwent the arthroscopic meniscectomy were evaluated. The patients with an average age of 26.7 years (range, 13–67) comprised 45 men and 11 women, 16 medial meniscus and 40 lateral meniscus injuries. The average of the follow-up period was 9.2 months. The parameter examined were age, the injured side of meniscus (medial or lateral), articular cartilage status, amount of resection, and sports activity level. Results The mean period was 54 days in young group, and was 89 days in old group (p = 0.0013). The period was 79 days in medial meniscus (MM) injured group, and was 61 days in lateral meniscus (LM) group (p = 0.017). There was a significant difference among the groups in activity levels and in amount of resection. Pain and/or effusion in the knee after the return-to-sport were found 22% of the MM group and 53% in the LM group. Conclusions The period of the return-to-sport was shorter in young age, high activity and large amount of resection group. Although athletes in LM group can return to sports earlier than those in MM group, more than half of athletes have pain or effusion at the time of return-to sport. PMID:24257295

  11. Bulgarian Turkish emigration and return.

    PubMed

    Vasileva, D

    1992-01-01

    The main factors which determined the 1989 migration of Turks in Bulgaria back to Turkey are discussed. Background history is provided. After World War I, Turks in bulgaria comprised 10% of the total population. Bulgarian policy had been, up to the 1980s to send Rumelian Turks back, but the policy after 1980 was one of a national revival process to integrate Turks into the developed socialist society. Muslim traditions, customs, and Turkish language were interfered with. International disfavor resulted. In May 1989, the Communist Party declared, in an effort to show democratic ideals, open borders. Thus began the new emigration wave. 369,839 people fled to the Turkish border. 43% of the 9.47 ethnic Turks in bulgaria went to Turkey within 4 months. The numbers decreased in November, and soon after the communist regime ended. New laws were adopted allowing Turks to assume their original Turkish names. The huge migration was clearly political, and as such, the emigrant Turks should be determined as refugees and asylum seekers. The provocation of ethnic Turks was used by the communist regime to solve potential social conflicts. Not only did Turks flee to escape from violence or for religious, cultural, and moral reasons but also due to free market initiatives begun in Turkey in the early 1980s which improved Turkish quality of life. Food and consumer goods were cheaper and economic advantages were perceived. Emigrants were primarily peasants with lower levels of education, professional qualifications, and labor skills. 154,937 (42%) returned to bulgaria and 58% stayed in Turkey to comprise 25% of the former Turkish population. During this period, tensions between countries was high.l Bulgarians actively encouraged emigration and Turkey welcomed it. The emigrants to Turkey were seen as foreigners (muhacir or gocmen) but were received with good will and were readily accepted into menial positions. Emigrants were confronted with political, linguistic, and cultural

  12. Non-Returning Student Survey.

    ERIC Educational Resources Information Center

    Charles County Community Coll., La Plata, MD. Dept. of Institutional Research and Assessment.

    In spring 1992, Charles County Community College (CCCC) conducted a telephone survey of non-returning fall 1991 students to determine their reasons for not returning to CCCC. In order to obtain comparison data, a questionnaire designed and administered by Prince George's Community College (PGCC) (Largo, Maryland) in 1988 was used with one minor…

  13. Capital Structure and Stock Returns

    ERIC Educational Resources Information Center

    Welch, Ivo

    2004-01-01

    U.S. corporations do not issue and repurchase debt and equity to counteract the mechanistic effects of stock returns on their debt-equity ratios. Thus over one- to five-year horizons, stock returns can explain about 40 percent of debt ratio dynamics. Although corporate net issuing activity is lively and although it can explain 60 percent of debt…

  14. Returns to Education and Economic Transition: An International Comparison

    ERIC Educational Resources Information Center

    Hung, Fan-sing

    2008-01-01

    This paper compares the returns to education in transitional economies in Central and Eastern Europe (CEE), such as Bulgaria, the Czech Republic, Romania, Russia, Slovak Republic and the Ukraine in the 1990s, and in China in the 1980s and 1990s. In the pre-transition period, the returns to education in the six CEE countries were low at about 2-4%,…

  15. Returning Evidence at the Appeals Council Level. Final rule.

    PubMed

    2016-02-01

    This final rule adopts the notice of proposed rulemaking (NPRM) that we published in the Federal Register on October 21, 2015. This final rule revises our rules regarding returning evidence at the Appeals Council (AC) level. Under this final rule, the AC will no longer return additional evidence it receives when the AC determines the additional evidence does not relate to the period on or before the date of the administrative law judge (ALJ) decision. PMID:26859901

  16. AKATSUKI returns to Venus

    NASA Astrophysics Data System (ADS)

    Nakamura, Masato; Imamura, Takeshi; Ishii, Nobuaki; Abe, Takumi; Kawakatsu, Yasuhiro; Hirose, Chikako; Satoh, Takehiko; Suzuki, Makoto; Ueno, Munetaka; Yamazaki, Atsushi; Iwagami, Naomoto; Watanabe, Shigeto; Taguchi, Makoto; Fukuhara, Tetsuya; Takahashi, Yukihiro; Yamada, Manabu; Imai, Masataka; Ohtsuki, Shoko; Uemizu, Kazunori; Hashimoto, George L.; Takagi, Masahiro; Matsuda, Yoshihisa; Ogohara, Kazunori; Sato, Naoki; Kasaba, Yasumasa; Kouyama, Toru; Hirata, Naru; Nakamura, Ryosuke; Yamamoto, Yukio; Horinouchi, Takeshi; Yamamoto, Masaru; Hayashi, Yoshi-Yuki; Kashimura, Hiroki; Sugiyama, Ko-ichiro; Sakanoi, Takeshi; Ando, Hiroki; Murakami, Shin-ya; Sato, Takao M.; Takagi, Seiko; Nakajima, Kensuke; Peralta, Javier; Lee, Yeon Joo; Nakatsuka, Junichi; Ichikawa, Tsutomu; Inoue, Kozaburo; Toda, Tomoaki; Toyota, Hiroyuki; Tachikawa, Sumitaka; Narita, Shinichiro; Hayashiyama, Tomoko; Hasegawa, Akiko; Kamata, Yukio

    2016-05-01

    AKATSUKI is the Japanese Venus Climate Orbiter that was designed to investigate the climate system of Venus. The orbiter was launched on May 21, 2010, and it reached Venus on December 7, 2010. Thrust was applied by the orbital maneuver engine in an attempt to put AKATSUKI into a westward equatorial orbit around Venus with a 30-h orbital period. However, this operation failed because of a malfunction in the propulsion system. After this failure, the spacecraft orbited the Sun for 5 years. On December 7, 2015, AKATSUKI once again approached Venus and the Venus orbit insertion was successful, whereby a westward equatorial orbit with apoapsis of ~440,000 km and orbital period of 14 days was initiated. Now that AKATSUKI's long journey to Venus has ended, it will provide scientific data on the Venusian climate system for two or more years. For the purpose of both decreasing the apoapsis altitude and avoiding a long eclipse during the orbit, a trim maneuver was performed at the first periapsis. The apoapsis altitude is now ~360,000 km with a periapsis altitude of 1000-8000 km, and the period is 10 days and 12 h. In this paper, we describe the details of the Venus orbit insertion-revenge 1 (VOI-R1) and the new orbit, the expected scientific information to be obtained at this orbit, and the Venus images captured by the onboard 1-µm infrared camera, ultraviolet imager, and long-wave infrared camera 2 h after the successful initiation of the VOI-R1.

  17. APOLLO 11: The heroes Return

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The crew of APOLLO 11 return as heroes after their succesfull landing on the lunar surface. From the film documentary 'APOLLO 11:'The Eagle Has Landed'', part of a documentary series on the APOLLO missions made in the early '70's and narrated by Burgess Meredith. APOLLO 11: First manned lunar landing and return to Earth with Neil A. Armstrong, Michael Collins, and Edwin E. Aldrin. Landed in the Sea of Tranquilityon July 20, 1969; deployed TV camera and EASEP experiments, performed lunar surface EVA, returned lunar soil samples. Mission Duration 195 hrs 18 min 35sec

  18. 26 CFR 301.7701(b)-4 - Residency time periods.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... statement (described in paragraph (c)(3)(v)(C) of this section) to the individual's income tax return (Form... tax return for the election year, the alien individual may request an extension of time for filing the return until a reasonable period after he or she has satisfied such test, provided that the...

  19. Irregular Periods

    MedlinePlus

    ... number of days after the last one. The Menstrual Cycle Most girls get their first period between the ... to skip periods or to have an irregular menstrual cycle. Illness, rapid weight change, or stress can also ...

  20. Earnings Quality Measures and Excess Returns

    PubMed Central

    Perotti, Pietro; Wagenhofer, Alfred

    2014-01-01

    This paper examines how commonly used earnings quality measures fulfill a key objective of financial reporting, i.e., improving decision usefulness for investors. We propose a stock-price-based measure for assessing the quality of earnings quality measures. We predict that firms with higher earnings quality will be less mispriced than other firms. Mispricing is measured by the difference of the mean absolute excess returns of portfolios formed on high and low values of a measure. We examine persistence, predictability, two measures of smoothness, abnormal accruals, accruals quality, earnings response coefficient and value relevance. For a large sample of US non-financial firms over the period 1988–2007, we show that all measures except for smoothness are negatively associated with absolute excess returns, suggesting that smoothness is generally a favorable attribute of earnings. Accruals measures generate the largest spread in absolute excess returns, followed by smoothness and market-based measures. These results lend support to the widespread use of accruals measures as overall measures of earnings quality in the literature. PMID:26300582

  1. Different forms, reasons and motivations for return migration of persons who voluntarily decide to return to their countries of origin.

    PubMed

    Callea, S

    1986-03-01

    Although the 1973 oil crisis did not have the drastic effects on immigration which were originally feared, it did end a period of quasi-liberal immigration policy, establish intense and effective international cooperation on immigration, and arouse great interest in immigration studies and research. This paper analyzes the situations arising as a result of the petroleum shortage and focuses on the conditions relating to the return of emigrants to Southern European countries. This new research draws attention to the following fundamental aspects of the immigration problem: 1) the emigrant's return to his homeland cannot be considered a factor in development; it is a positive element in development only if the right socioeconomic conditions exist in the country of origin. 2) Concern for children's education is one of the most common reasons for return. 3) A large percentage of emigrants are satisfied with their work abroad. 4) An emigrant's return potential is wasted due to the slight use that is made of the resources he offers. 5) Returning workers most often want to set up an independent enterprise. 6) Savings are generally used to buy a house or farm. 7) Vocational level does not increase significantly between emigration and returning, though this increase becomes greater the longer the emigrant stays abroad. 8) The number of returning emigrants is too slight to bring about any change in the country of origin. 9) Incentives and subsidies to encourage return have not had a considerable impact on the decision to return. Callea recommends that officials of the country of origin posted abroad be assigned to counsel returning emigrants on finding employment, attending vocational development courses, obtaining housing, accruing interests and savings, and on the problems and perspectives of sociocultural reintegration. PMID:12314946

  2. Leaving from and returning to nursing practice: contributing factors.

    PubMed

    Jamieson, Isabel; Taua, Chris

    2009-07-01

    Many nurses leave nursing and never return. Others return after a period of time. Given the global shortage of nurses a better understanding of these movements is needed. The present study focused on nurses who had been out of nursing for more than five years, and explored factors that influenced their leaving and return to practice. All the nurses who had undertaken a Competency Assessment Programme at a given New Zealand tertiary institution during 2005 were invited to participate. Of the 70 questionnaires mailed out 32 (44.5%) were completed and returned. Quantitative data were analysed using Microsoft Excel, and the qualitative data were coded and analysed by means of content analysis. For each, leaving and returning, three key issues emerged. Nurses left for personal reasons, to seek a career change, or because of poor working conditions. They returned when they had the personal freedom to do so, for fiscal reasons, or because they were motivated by some sense of unfinished business. These findings indicate that it is important for educators involved with Competency Assessment Programmes to collaborate with employers in ensuring that there are opportunities for re-entry to positive work environments, with a degree of flexibility that suits the demographic characteristics of those nurses returning to practice. PMID:19928648

  3. 28 CFR 540.24 - Returned mail.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... contraband all undelivered mail returned to an institution by the Post Office before returning it to the.... Any returned mail qualifying as “special mail” is opened and inspected for contraband in the...

  4. 28 CFR 540.24 - Returned mail.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... contraband all undelivered mail returned to an institution by the Post Office before returning it to the.... Any returned mail qualifying as “special mail” is opened and inspected for contraband in the...

  5. Predictors of returning to work.

    PubMed

    Ash, P; Goldstein, S I

    1995-01-01

    An investigation of predictors of returning to work in a sample of physically injured persons who are receiving workers' compensation benefits and vocational rehabilitation is presented. One hundred fourteen injured subjects (86 with back injury; 28, other injury) undergoing vocational rehabilitation and receiving workers' compensation benefits were assessed on demographic, emotional, cognitive, financial incentive, and miscellaneous variables. Predictors for returning to work were identified using stepwise logistic regression. Patients with moderate or severe depression, defined as a score greater than 16 on the Beck Depression Inventory (BDI), were significantly less likely to return to work following vocational rehabilitation efforts than patients with less severe depression (for back-injured patients, odds ratio (OR) = 31, 95% CI [8.8, 108]). BDI scores correctly classified 84 percent of the back-injury and 86% of the other-injury groups with respect to their return to work. The level of workers' compensation benefit was the only variable that added (marginally) to the predictive power of the BDI. In a physically injured population receiving workers' compensation benefits, who are judged to be not clearly permanently disabled, level of depressive symptoms is a strong predictor of returning to work. Caution is warranted in using the BDI as the sole determinant in a forensic situation for making a real-world prediction, as BDI responses are easy to fake. Treatment of concurrent depression is an important component of helping physically injured workers resume gainful employment. PMID:8605404

  6. Probability distribution of extreme share returns in Malaysia

    NASA Astrophysics Data System (ADS)

    Zin, Wan Zawiah Wan; Safari, Muhammad Aslam Mohd; Jaaman, Saiful Hafizah; Yie, Wendy Ling Shin

    2014-09-01

    The objective of this study is to investigate the suitable probability distribution to model the extreme share returns in Malaysia. To achieve this, weekly and monthly maximum daily share returns are derived from share prices data obtained from Bursa Malaysia over the period of 2000 to 2012. The study starts with summary statistics of the data which will provide a clue on the likely candidates for the best fitting distribution. Next, the suitability of six extreme value distributions, namely the Gumbel, Generalized Extreme Value (GEV), Generalized Logistic (GLO) and Generalized Pareto (GPA), the Lognormal (GNO) and the Pearson (PE3) distributions are evaluated. The method of L-moments is used in parameter estimation. Based on several goodness of fit tests and L-moment diagram test, the Generalized Pareto distribution and the Pearson distribution are found to be the best fitted distribution to represent the weekly and monthly maximum share returns in Malaysia stock market during the studied period, respectively.

  7. Cells anticipate periodic events

    NASA Astrophysics Data System (ADS)

    Nakagaki, Toshiyuki

    2009-03-01

    We show that an amoeboid organism can anticipate the timing of periodic events. The plasmodium of the true slime mold Physarum polycephalum moves rapidly under favourable conditions, but stops moving when transferred to less-favourable conditions. Plasmodia exposed to unfavourable conditions, presented in three consecutive pulses at constant intervals, reduced their locomotive speed in response to each episode. When subsequently subjected to favourable conditions, the plasmodia spontaneously reduced their locomotive speed at the time point when the next unfavourable episode would have occurred. This implied anticipation of impending environmental change. After this behaviour had been evoked several times, the locomotion of the plasmodia returned to normal; however, the anticipatory response could subsequently be induced by a single unfavourable pulse, implying recall of the memorized periodicity. We explored the mechanisms underlying these behaviours from a dynamical systems perspective. Our results hint at the cellular origins of primitive intelligence and imply that simple dynamics might be sufficient to explain its emergence.

  8. 26 CFR 1.6038-3 - Information returns required of certain United States persons with respect to controlled foreign...

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... provided by Form 8865 and the accompanying instructions. The return must contain all of the information... provisions of § 1.761-2(b)(2)(ii). (f) Period covered by return. The information required under this section... filing the return; and (vi) Any other information that Form 8865 or its accompanying instructions...

  9. 26 CFR 1.6038-3 - Information returns required of certain United States persons with respect to controlled foreign...

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... provided by Form 8865 and the accompanying instructions. The return must contain all of the information... provisions of § 1.761-2(b)(2)(ii). (f) Period covered by return. The information required under this section... filing the return; and (vi) Any other information that Form 8865 or its accompanying instructions...

  10. Measuring the Earnings Returns to Lifelong Learning in the UK

    ERIC Educational Resources Information Center

    Blanden, Jo; Buscha, Franz; Sturgis, Patrick; Urwin, Peter

    2012-01-01

    This paper examines the earnings returns to learning that takes place following the conventional "school-to-work" stage of the life-course. We operationalise such "lifelong learning" as the attainment of certified qualifications in adulthood, following the completion of the first period of continuous full-time education. Using data from the…

  11. Rates of Return to Educational Qualifications in the Transitional Economies.

    ERIC Educational Resources Information Center

    Newell, Andrew; Reilly, Barry

    1999-01-01

    Provides cross-country estimates on private rates of return to higher-education qualifications across various transitional economies spanning Central and Eastern Europe, Russia, and the former Soviet Union. Rates tend to rise in most transitional economies over the period considered. Rate variabilities help explain variabilities in wage…

  12. Gender Gap in Returns to Schooling in Palestine

    ERIC Educational Resources Information Center

    Daoud, Yousef

    2005-01-01

    This study provides estimates of the private returns to schooling in Palestine utilizing eight quarterly labor force surveys for 1999 and 2001. This period was chosen to investigate the differential impact of the Israeli closure policy on Palestinian male and female workers. Although gross enrollment ratios for males and females reveal little to…

  13. 48 CFR 52.247-66 - Returnable Cylinders.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... higher than 40 psia and having a circular cross section excluding a portable tank, multitank car tank, cargo tank or tank car. (b) Returnable cylinders shall remain the Contractor's property but shall be... within the loan period shall be charged a daily rental beginning with the first day after the loan...

  14. 48 CFR 52.247-66 - Returnable Cylinders.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... higher than 40 psia and having a circular cross section excluding a portable tank, multitank car tank, cargo tank or tank car. (b) Returnable cylinders shall remain the Contractor's property but shall be... within the loan period shall be charged a daily rental beginning with the first day after the loan...

  15. 48 CFR 52.247-66 - Returnable Cylinders.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... higher than 40 psia and having a circular cross section excluding a portable tank, multitank car tank, cargo tank or tank car. (b) Returnable cylinders shall remain the Contractor's property but shall be... within the loan period shall be charged a daily rental beginning with the first day after the loan...

  16. 48 CFR 52.247-66 - Returnable Cylinders.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... higher than 40 psia and having a circular cross section excluding a portable tank, multitank car tank, cargo tank or tank car. (b) Returnable cylinders shall remain the Contractor's property but shall be... within the loan period shall be charged a daily rental beginning with the first day after the loan...

  17. 48 CFR 52.247-66 - Returnable Cylinders.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... higher than 40 psia and having a circular cross section excluding a portable tank, multitank car tank, cargo tank or tank car. (b) Returnable cylinders shall remain the Contractor's property but shall be... within the loan period shall be charged a daily rental beginning with the first day after the loan...

  18. 18 CFR 154.403 - Periodic rate adjustments.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Periodic rate adjustments. 154.403 Section 154.403 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY... recovery or return, the past period must be defined and the mechanism for the recovery or return must...

  19. Uncertain Educational Returns in a Developing Economy

    ERIC Educational Resources Information Center

    Mohapatra, Sandeep; Luckert, Martin K.

    2012-01-01

    This paper estimates the distribution of educational returns by gender for India. While previous studies focus on mean returns, the variance of educational returns has important implications for policy-making and micro-level decision making with respect to education. If the variance of educational returns is large, it can leave large sections of…

  20. 26 CFR 1.6001-2 - Returns.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 26 Internal Revenue 13 2013-04-01 2013-04-01 false Returns. 1.6001-2 Section 1.6001-2 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Information and Returns § 1.6001-2 Returns. For rules relating to returns required...

  1. 26 CFR 1.6001-2 - Returns.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 13 2012-04-01 2012-04-01 false Returns. 1.6001-2 Section 1.6001-2 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Information and Returns § 1.6001-2 Returns. For rules relating to returns required...

  2. 26 CFR 1.6001-2 - Returns.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 13 2011-04-01 2011-04-01 false Returns. 1.6001-2 Section 1.6001-2 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Information and Returns § 1.6001-2 Returns. For rules relating to returns required...

  3. 26 CFR 1.6001-2 - Returns.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 13 2010-04-01 2010-04-01 false Returns. 1.6001-2 Section 1.6001-2 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Information and Returns § 1.6001-2 Returns. For rules relating to returns required to be made...

  4. Return to activity following fasciotomy for chronic exertional compartment syndrome.

    PubMed

    Irion, Val; Magnussen, Robert A; Miller, Timothy L; Kaeding, Christopher C

    2014-10-01

    Diagnosis of chronic exertional compartment syndrome (CECS) is relatively rare but has been well documented in athletes. There are, however, few reports regarding return to athletic activity after surgery among elite-level athletes. We hypothesized that a majority of elite-level athletes would successfully return to their previous level of competition following fasciotomy for CECS. A retrospective chart review was performed to identify elite-level athletes (collegiate or professional sport participation) who underwent fasciotomy for CECS over a 3-year period. Data collected included sport or activity, treatment and surgical details, time away from sport/activity after surgery, and ability to return to prior level of activity. Six males and seven females were included in the analysis. Patient age ranged from 17 to 24 years with a mean of 19.7 years. Six patients underwent unilateral lower extremity compartment release, and seven underwent bilateral lower extremity compartment release. The anterior and lateral compartments alone were released in 11 patients (84.6%). Two patients (15.4%) underwent four-compartment releases. Eleven patients (84.6%) were able to return to their previous elite level of sport participation at a mean of 10.6 weeks following surgical fasciotomy. Patients who had four-compartment release had a more than 3.5 week average longer return to full sporting activities (p = 0.011). Fasciotomy is effective in allowing elite athletes with CECS to return to sport. PMID:24664450

  5. Periodized wavelets

    SciTech Connect

    Schlossnagle, G.; Restrepo, J.M.; Leaf, G.K.

    1993-12-01

    The properties of periodized Daubechies wavelets on [0,1] are detailed and contrasted against their counterparts which form a basis for L{sup 2}(R). Numerical examples illustrate the analytical estimates for convergence and demonstrate by comparison with Fourier spectral methods the superiority of wavelet projection methods for approximations. The analytical solution to inner products of periodized wavelets and their derivatives, which are known as connection coefficients, is presented, and several tabulated values are included.

  6. Heat Pipe Blocks Return Flow

    NASA Technical Reports Server (NTRS)

    Eninger, J. E.

    1982-01-01

    Metal-foil reed valve in conventional slab-wick heat pipe limits heat flow to one direction only. With sink warmer than source, reed is forced closed and fluid returns to source side through annular transfer wick. When this occurs, wick slab on sink side of valve dries out and heat pipe ceases to conduct heat.

  7. Return to the Red Planet

    NASA Technical Reports Server (NTRS)

    Lee, W.

    1996-01-01

    In November 1996, NASA and the Jet Propulsion Laboratory will begin America's return to Mars after a 20-year absence by launching the Mars Global Surveyor (MGS) spacecraft. This mission will usher in a new and exciting era of scientific missions to study the red planet.

  8. Return to the Social Studies.

    ERIC Educational Resources Information Center

    Consuela, Sister Mary

    In this speech, a plea is made to return content to the social studies. Content is seen as essential to cognitive and affective learning. Although the author feels that the introduction of behavioral objectives is a significant development of the various social studies projects, it is meaningless unless it is related to content. Clearly stated…

  9. Comet coma sample return instrument

    NASA Technical Reports Server (NTRS)

    Albee, A. L.; Brownlee, Don E.; Burnett, Donald S.; Tsou, Peter; Uesugi, K. T.

    1994-01-01

    The sample collection technology and instrument concept for the Sample of Comet Coma Earth Return Mission (SOCCER) are described. The scientific goals of this Flyby Sample Return are to return to coma dust and volatile samples from a known comet source, which will permit accurate elemental and isotopic measurements for thousands of individual solid particles and volatiles, detailed analysis of the dust structure, morphology, and mineralogy of the intact samples, and identification of the biogenic elements or compounds in the solid and volatile samples. Having these intact samples, morphologic, petrographic, and phase structural features can be determined. Information on dust particle size, shape, and density can be ascertained by analyzing penetration holes and tracks in the capture medium. Time and spatial data of dust capture will provide understanding of the flux dynamics of the coma and the jets. Additional information will include the identification of cosmic ray tracks in the cometary grains, which can provide a particle's process history and perhaps even the age of the comet. The measurements will be made with the same equipment used for studying micrometeorites for decades past; hence, the results can be directly compared without extrapolation or modification. The data will provide a powerful and direct technique for comparing the cometary samples with all known types of meteorites and interplanetary dust. This sample collection system will provide the first sample return from a specifically identified primitive body and will allow, for the first time, a direct method of matching meteoritic materials captured on Earth with known parent bodies.

  10. Neurocognitive Performance: Returning to Competition

    ERIC Educational Resources Information Center

    McDaniel, Larry W.; McIntire, Kyle

    2010-01-01

    Athletes who suffer from concussions under report their symptoms in order to expedite their return to competition. Athletic trainers and coaches must be aware of what is going on with athletes, even if it means requiring them to refrain from competition. Ninety percent of concussions are minor and can be difficult to diagnosis. There is a lack of…

  11. Skin lesions in returning travellers.

    PubMed

    Korzeniewski, Krzysztof; Juszczak, Dariusz; Jerzemowski, Janusz

    2015-01-01

    Skin lesions, apart from diarrhoeas, fever of unknown origin, and respiratory tract infections belong to the most frequent medical problems in travellers returned from tropical and subtropical destinations, accounting more than 10% of reported cases. Most dermatoses have their clinical onset during travel, although some of them can occur after return. Travel-related dermatological problems can have a wide spectrum of clinical picture, from macular, popular or nodular rash, linear and migratory lesions, to plaques, vesicles, bullae, erosions or ulcers. Skin conditions in returning travellers may be of infectious and non-infectious aetiologies. Infectious lesions may be originally tropical (e.g. dengue, chikungunya, schistosomiasis, leishmaniasis, myiasis, tungiasis, loiasis), although the majority are cosmopolitan (arthropod bites, sunburns, allergic rashes). The evaluation of skin lesions depends on many factors, including immune status of patients, use of medicines, exposure on health hazards (fauna, flora, risky behaviours), as well as the time, duration and location of travel. As the number of travellers to tropical and subtropical destinations has been continuously rising, the number of skin illnesses has also been increasing. This means that specialists in travel medicine need to extend their knowledge of epidemiology, clinical features and diagnosis of travel-related health problems including skin lesions in returning travellers. PMID:26394319

  12. The Returns to Apprenticeship Training

    ERIC Educational Resources Information Center

    McIntosh, Steven

    2005-01-01

    This paper uses recent data from the UK Labour Force Survey to estimate the wage gains that individuals make on average if they complete an apprenticeship programme. The results suggest gains of around 5-7% for men, but no benefit for women. Further analysis extends the results by considering the returns by age group, by qualification obtained, by…

  13. The Returns to Community College

    ERIC Educational Resources Information Center

    Agan, Amanda Yvonne

    2013-01-01

    Almost half of postsecondary students are currently enrolled in community colleges. These institutions imply that even amongst students with the same degree outcome there is considerable heterogeneity in the path taken to get there. I estimate the life-cycle private and social returns to the different postsecondary paths and sequential decisions…

  14. Analysing Enterprise Returns on Training.

    ERIC Educational Resources Information Center

    Moy, Janelle; McDonald, Rod

    Recent Australian and overseas studies on evaluation of enterprises' return on training investment (ROTI) were reviewed to identify key issues in encouraging increased evaluation of training benefits by enterprises and successful approaches that may inform future "enterprise-friendly" studies of ROTI. It was concluded that more practical,…

  15. Facilitating Successful Re-Entries in the United States: Training and Development for Women Returners

    ERIC Educational Resources Information Center

    Greer, Tomika W.

    2013-01-01

    Women returners are women who leave the paid workforce for a period of time following the birth of their child(ren) and subsequently seek to return to paid employment. As women returners attempt to re-enter the workforce, many of them are in need of updating their skills or re-training in a new set of skills. In this study, the training and…

  16. 26 CFR 31.6071(a)-1 - Time for filing returns and other documents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... it is made. (3) Information returns—(i) General rule. Each information return in respect of wages as... § 31.6011(a)-5(a) is filed as a final return for a period ending prior to December 31, the information... return required to be made under §§ 31.6011(a)-1 and 31.6011(a)-1T, in respect of the taxes imposed...

  17. Phobos Sample Return: Next Approach

    NASA Astrophysics Data System (ADS)

    Zelenyi, Lev; Martynov, Maxim; Zakharov, Alexander; Korablev, Oleg; Ivanov, Alexey; Karabadzak, George

    The Martian moons still remain a mystery after numerous studies by Mars orbiting spacecraft. Their study cover three major topics related to (1) Solar system in general (formation and evolution, origin of planetary satellites, origin and evolution of life); (2) small bodies (captured asteroid, or remnants of Mars formation, or reaccreted Mars ejecta); (3) Mars (formation and evolution of Mars; Mars ejecta at the satellites). As reviewed by Galimov [2010] most of the above questions require the sample return from the Martian moon, while some (e.g. the characterization of the organic matter) could be also answered by in situ experiments. There is the possibility to obtain the sample of Mars material by sampling Phobos: following to Chappaz et al. [2012] a 200-g sample could contain 10-7 g of Mars surface material launched during the past 1 mln years, or 5*10-5 g of Mars material launched during the past 10 mln years, or 5*1010 individual particles from Mars, quantities suitable for accurate laboratory analyses. The studies of Phobos have been of high priority in the Russian program on planetary research for many years. Phobos-88 mission consisted of two spacecraft (Phobos-1, Phobos-2) and aimed the approach to Phobos at 50 m and remote studies, and also the release of small landers (long-living stations DAS). This mission implemented the program incompletely. It was returned information about the Martian environment and atmosphere. The next profect Phobos Sample Return (Phobos-Grunt) initially planned in early 2000 has been delayed several times owing to budget difficulties; the spacecraft failed to leave NEO in 2011. The recovery of the science goals of this mission and the delivery of the samples of Phobos to Earth remain of highest priority for Russian scientific community. The next Phobos SR mission named Boomerang was postponed following the ExoMars cooperation, but is considered the next in the line of planetary exploration, suitable for launch around 2022. A

  18. The Genesis Solar Wind Sample Return Mission

    NASA Technical Reports Server (NTRS)

    Wiens, Roger C.; Burnett, Donald S.; Neugebauer, Marcia; Sasaki, Chester; Sevilla, Donald; Stansbery, Eileen; Clark, Ben; Smith, Nick; Oldham, Lloyd

    1990-01-01

    The Genesis spacecraft was launched on August 8 from Cape Canaveral on a journey to become the first spacecraft to return from interplanetary space. The fifth in NASA's line of low-cost Discovery-class missions, its goal is to collect samples of solar wind and return them to Earth for detailed isotopic and elemental analysis. The spacecraft is to collect solar wind for over two years, while circling the L1 point 1.5 million km sunward of the earth, before heading back for a capsule-style re-entry in September, 2004. After parachute deployment, a mid-air helicopter recovery will be used to avoid a hard landing. The mission has been in the planning stages for over ten years. Its cost, including development, mission operations, and sample analysis, is approximately $209M. The Genesis science team, headed by principal investigator Donald Burnett of Caltech, consists of approximately 20 co-investigators from universities and science centers around the country and internationally. The spacecraft consists of a relatively flat spacecraft bus containing most of the subsystem components, situated below a sample return capsule (SRC) which holds the solar-wind collection substrates and an electrostatic solar wind concentrator. Some of the collectors are exposed throughout the collection period, for a sample of bulk solar wind, while others are exposed only to certain solar wind regimes, or types of flow. Ion and electron spectrometers feed raw data to the spacecraft control and data-handling (C&DH) unit, which determines ion moments and electron flux geometries in real time. An algorithm is used to robotically decide between interstream (IS), coronal hole (CH), and coronal mass ejection (CME) regimes, and to control deployment of the proper arrays to sample these wind regimes independently. This is the first time such a solar-wind decision algorithm has been used on board a spacecraft.

  19. 26 CFR 1.6013-2 - Joint return after filing separate return.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 13 2010-04-01 2010-04-01 false Joint return after filing separate return. 1... filing separate return. (a) In general. (1) Where an individual has filed a separate return for a taxable... separate return of either spouse are to be taken into account in determining the extent to which the...

  20. 26 CFR 1.6013-2 - Joint return after filing separate return.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 13 2011-04-01 2011-04-01 false Joint return after filing separate return. 1.6013-2 Section 1.6013-2 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Tax Returns Or Statements § 1.6013-2 Joint return after filing separate return. (a) In general....

  1. 26 CFR 20.6075-1 - Returns; time for filing estate tax return.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 14 2011-04-01 2010-04-01 true Returns; time for filing estate tax return. 20.6075-1 Section 20.6075-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... Administration § 20.6075-1 Returns; time for filing estate tax return. The estate tax return required by...

  2. 26 CFR 20.6075-1 - Returns; time for filing estate tax return.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 14 2010-04-01 2010-04-01 false Returns; time for filing estate tax return. 20.6075-1 Section 20.6075-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... Administration § 20.6075-1 Returns; time for filing estate tax return. The estate tax return required by...

  3. Mars Double-Flyby Free Returns

    NASA Technical Reports Server (NTRS)

    Jesick, Mark

    2015-01-01

    A subset of Earth-originating Mars double-flyby ballistic trajectories is documented. The subset consists of those trajectories that, after the first Mars flyby, perform a half-revolution transfer with Mars before returning to Earth. This class of free returns is useful for both human and robotic Mars missions because of its low geocentric energy at departure and arrival, and because of its extended stay time in the vicinity of Mars. Ballistic opportunities are documented over Earth departure dates ranging from 2015 through 2100. The mission is viable over three or four consecutive Mars synodic periods and unavailable for the next four, with the pattern repeating approximately every 15 years. Over the remainder of the century, a minimum Earth departure hyperbolic excess speed of 3.16 km/s, a minimum Earth atmospheric entry speed of 11.47 km/s, and a minimum flight time of 904 days are observed. The algorithm used to construct these trajectories is presented along with several examples.

  4. Periodic cages.

    PubMed

    Diudea, Mircea V; Nagy, Csaba L; Silaghi-Dumitrescu, Ioan; Graovac, Ante; Janezic, Dusanka; Vikić-Topić, Drazen

    2005-01-01

    Various cages are constructed by using three types of caps: f-cap (derived from spherical fullerenes by deleting zones of various size), kf-cap (obtainable by cutting off the polar ring, of size k), and t-cap ("tubercule"-cap). Building ways are presented, some of them being possible isomerization routes in the real chemistry of fullerenes. Periodic cages with ((5,7)3) covering are modeled, and their constitutive typing enumeration is given. Spectral data revealed some electronic periodicity in fullerene clusters. Semiempirical and strain energy calculations complete their characterization. PMID:15807490

  5. 27 CFR 26.112 - Returns for deferred payment of tax.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... payment of tax and filing the return will be the 14th day after the last day of the calendar quarter... 26 U.S.C. 7652 under the same Employer Identification Number as defined in 26 CFR 301.7701-12. (2... provided in paragraph (e) of this section. (3) Quarterly return period. Effective January 1, 2006,...

  6. Returns to Education in the Economic Transition: A Systematic Assessment Using Comparable Data

    ERIC Educational Resources Information Center

    Flabbi, Luca; Paternostro, Stefano; Tiongson, Erwin R.

    2008-01-01

    This paper studies a sample of economies in transition to verify the assertion that returns to schooling increase as an economy transitions to a market environment. This claim has been difficult to assess in the past as the empirical evidence so far has covered only a few countries over short time periods. A number of studies find that returns to…

  7. Changes in the Returns to Schooling 1991-2002: Evidence from the British Household Panel Survey

    ERIC Educational Resources Information Center

    McGuinness, Seamus; Bennett, Jessica

    2009-01-01

    The present paper uses British Household Panel Survey data from 1991 to 2002 to assess the extent to which labour market returns have been influenced by changes in the nature of educational supply. We find that whilst there have been substantial shifts in the returns to schooling over the period, these effects are much more pronounced for younger…

  8. Parents Returning to Work: Evaluation of Grant Recipient Outcomes 2004-05, 2005-06

    ERIC Educational Resources Information Center

    Ferrier, Fran; Kellock, Peter; Burke, Gerald

    2007-01-01

    The Parents Returning to Work Program (PRTW) is a Victorian government initiative which commenced in 2003. It provides grants to assist eligible parents who wish to return to paid employment after a period of caring for children to participate in training that will increase their work skills and job prospects. This evaluation aimed to review the…

  9. The Scientific Return of VLT Programmes

    NASA Astrophysics Data System (ADS)

    Sterzik, M.; Dumas, C.; Grothkopf, U.; Kaufer, A.; Leibundgut, B.; Marteau, S.; Meakins, S.; Patat, F.; Primas, F.; Rejkuba, M.; Romaniello, M.; Stoehr, F.; Tacconi-Garman, L.; Vera, I.

    2015-12-01

    An in-depth analysis of the publications from 8414 distinct scheduled VLT observing programmes between April 1999 and March 2015 (Periods 63 to 94) is presented. The productivity by mode (Visitor or Service Mode) and type (Normal and Large, Guaranteed Time, Target of Opportunity, Director's Discretionary Time) are examined through their publication records. We investigate how Service Mode rank classes impact the scientific return. Several results derive from this study: Large Programmes result in the highest productivity, whereas only about half of all scheduled observing programmes produce a refereed publication. Programmes that result in a publication yield on average two refereed papers. B rank class Service Mode Programmes appear to be slightly less productive. Follow-up studies will investigate in more detail the parameters that influence the productivity of the Observatory.

  10. Quantifying Stock Return Distributions in Financial Markets

    PubMed Central

    Botta, Federico; Moat, Helen Susannah; Stanley, H. Eugene; Preis, Tobias

    2015-01-01

    Being able to quantify the probability of large price changes in stock markets is of crucial importance in understanding financial crises that affect the lives of people worldwide. Large changes in stock market prices can arise abruptly, within a matter of minutes, or develop across much longer time scales. Here, we analyze a dataset comprising the stocks forming the Dow Jones Industrial Average at a second by second resolution in the period from January 2008 to July 2010 in order to quantify the distribution of changes in market prices at a range of time scales. We find that the tails of the distributions of logarithmic price changes, or returns, exhibit power law decays for time scales ranging from 300 seconds to 3600 seconds. For larger time scales, we find that the distributions tails exhibit exponential decay. Our findings may inform the development of models of market behavior across varying time scales. PMID:26327593

  11. Quantifying Stock Return Distributions in Financial Markets.

    PubMed

    Botta, Federico; Moat, Helen Susannah; Stanley, H Eugene; Preis, Tobias

    2015-01-01

    Being able to quantify the probability of large price changes in stock markets is of crucial importance in understanding financial crises that affect the lives of people worldwide. Large changes in stock market prices can arise abruptly, within a matter of minutes, or develop across much longer time scales. Here, we analyze a dataset comprising the stocks forming the Dow Jones Industrial Average at a second by second resolution in the period from January 2008 to July 2010 in order to quantify the distribution of changes in market prices at a range of time scales. We find that the tails of the distributions of logarithmic price changes, or returns, exhibit power law decays for time scales ranging from 300 seconds to 3600 seconds. For larger time scales, we find that the distributions tails exhibit exponential decay. Our findings may inform the development of models of market behavior across varying time scales. PMID:26327593

  12. Asteroid Return Mission Feasibility Study

    NASA Technical Reports Server (NTRS)

    Brophy, John R.; Gershman, Robert; Landau, Damon; Polk, James; Porter, Chris; Yeomans, Don; Allen, Carlton; Williams, Willie; Asphaug, Erik

    2011-01-01

    This paper describes an investigation into the technological feasibility of finding, characterizing, robotically capturing, and returning an entire Near-Earth Asteroid (NEA) to the International Space Station (ISS) for scientific investigation, evaluation of its resource potential, determination of its internal structure and other aspects important for planetary defense activities, and to serve as a testbed for human operations in the vicinity of an asteroid. Reasonable projections suggest that several dozen candidates NEAs in the size range of interest (approximately 2-m diameter) will be known before the end of the decade from which a suitable target could be selected. The conceptual mission objective is to return an approximately 10,000-kg asteroid to the ISS in a total flight time of approximately 5 years using a single Evolved Expendable Launch Vehicle. Preliminary calculations indicate that this could be accomplished using a solar electric propulsion (SEP) system with high-power Hall thrusters and a maximum power into the propulsion system of approximately 40 kW. The SEP system would be used to provide all of the post-launch delta V. The asteroid would have an unrestricted Earth return Planetary Protection categorization, and would be curated at the ISS where numerous scientific and resource utilization experiments would be conducted. Asteroid material brought to the ground would be curated at the NASA Johnson Space Center. This preliminary study identified several areas where additional work is required, but no show stoppers were identified for the approach that would return an entire 10,000-kg asteroid to the ISS in a mission that could be launched by the end of this decade.

  13. Comet nucleus sample return mission

    NASA Technical Reports Server (NTRS)

    1983-01-01

    A comet nucleus sample return mission in terms of its relevant science objectives, candidate mission concepts, key design/technology requirements, and programmatic issues is discussed. The primary objective was to collect a sample of undisturbed comet material from beneath the surface of an active comet and to preserve its chemical and, if possible, its physical integrity and return it to Earth in a minimally altered state. The secondary objectives are to: (1) characterize the comet to a level consistent with a rendezvous mission; (2) monitor the comet dynamics through perihelion and aphelion with a long lived lander; and (3) determine the subsurface properties of the nucleus in an area local to the sampled core. A set of candidate comets is discussed. The hazards which the spacecraft would encounter in the vicinity of the comet are also discussed. The encounter strategy, the sampling hardware, the thermal control of the pristine comet material during the return to Earth, and the flight performance of various spacecraft systems and the cost estimates of such a mission are presented.

  14. Tick size and stock returns

    NASA Astrophysics Data System (ADS)

    Onnela, Jukka-Pekka; Töyli, Juuso; Kaski, Kimmo

    2009-02-01

    Tick size is an important aspect of the micro-structural level organization of financial markets. It is the smallest institutionally allowed price increment, has a direct bearing on the bid-ask spread, influences the strategy of trading order placement in electronic markets, affects the price formation mechanism, and appears to be related to the long-term memory of volatility clustering. In this paper we investigate the impact of tick size on stock returns. We start with a simple simulation to demonstrate how continuous returns become distorted after confining the price to a discrete grid governed by the tick size. We then move on to a novel experimental set-up that combines decimalization pilot programs and cross-listed stocks in New York and Toronto. This allows us to observe a set of stocks traded simultaneously under two different ticks while holding all security-specific characteristics fixed. We then study the normality of the return distributions and carry out fits to the chosen distribution models. Our empirical findings are somewhat mixed and in some cases appear to challenge the simulation results.

  15. The Mars Sample Return Project.

    PubMed

    O'Neil, W J; Cazaux, C

    2000-01-01

    The Mars Sample Return (MSR) Project is underway. A 2003 mission to be launched on a Delta III Class vehicle and a 2005 mission launched on an Ariane 5 will culminate in carefully selected Mars samples arriving on Earth in 2008. NASA is the lead agency and will provide the Mars landed elements, namely, landers, rovers, and Mars ascent vehicles (MAVs). The French Space Agency CNES is the largest international partner and will provide for the joint NASA/CNES 2005 Mission the Ariane 5 launch and the Earth Return Mars Orbiter that will capture the sample canisters from the Mars parking orbits the MAVs place them in. The sample canisters will be returned to Earth aboard the CNES Orbiter in the Earth Entry Vehicles provided by NASA. Other national space agencies are also expected to participate in substantial roles. Italy is planning to provide a drill that will operate from the Landers to provide subsurface samples. Other experiments in addition to the MSR payload will also be carried on the Landers. This paper will present the current status of the design of the MSR missions and flight articles. PMID:11708368

  16. 26 CFR 301.6103(c)-1 - Disclosure of returns and return information to designee of taxpayer.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 18 2014-04-01 2014-04-01 false Disclosure of returns and return information to... and Returns Returns and Records § 301.6103(c)-1 Disclosure of returns and return information to... Service to disclose a taxpayer's return or return information to such person or persons as the...

  17. 26 CFR 301.6103(c)-1 - Disclosure of returns and return information to designee of taxpayer.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 26 Internal Revenue 18 2013-04-01 2013-04-01 false Disclosure of returns and return information to... and Returns Returns and Records § 301.6103(c)-1 Disclosure of returns and return information to... Service to disclose a taxpayer's return or return information to such person or persons as the...

  18. 26 CFR 301.6103(c)-1 - Disclosure of returns and return information to designee of taxpayer.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 18 2012-04-01 2012-04-01 false Disclosure of returns and return information to... and Returns Returns and Records § 301.6103(c)-1 Disclosure of returns and return information to... Service to disclose a taxpayer's return or return information to such person or persons as the...

  19. 26 CFR 301.6103(c)-1 - Disclosure of returns and return information to designee of taxpayer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 18 2011-04-01 2011-04-01 false Disclosure of returns and return information to... and Returns Returns and Records § 301.6103(c)-1 Disclosure of returns and return information to... Service to disclose a taxpayer's return or return information to such person or persons as the...

  20. The Gulliver sample return mission to Deimos

    NASA Astrophysics Data System (ADS)

    Britt, D. T.; Robinson, M.; Gulliver Team

    The Martian moon Deimos presents a unique opportunity for a sample return mission. Deimos is spectrally analogous to type D asteroids, which are thought to be composed of highly primitive carbonaceous material that originated in the outer asteroid belt. It also is in orbit around Mars and has been accumulating material ejected from the Martian surface ever since the earliest periods of Martian history, over 4.4 Gyrs ago. There are a number of factors that make sample return from Deimos extremely attractive. It is Better: Deimos is a repository for two kinds of extremely significant and scientifically exciting ancient samples: (1) Primitive spectral D-type material that may have accreted in the outer asteroid belt and Trojan swarm. This material samples the composition of solar nebula well outside the zone of terrestrial planets and provides a direct sample of primitive material so common past 3 AU but so uncommon in the meteorite collection. (2) Ancient Mars, which could include the full range of Martian crustal and upper mantle material from the early differentiation and crustal-forming epoch as well as samples from the era of high volatile flux, thick atmosphere, and possible surface water. The Martian material on Deimos would be dominated by ejecta from the ancient crust of Mars, delivered during the Noachian Period of basin-forming impacts and heavy bombardment. It is Closer: Compared to other primitive D-type asteroids, Deimos is by far the most accessible. Because of its orbit around Mars, Deimos is far closer than any other D asteroid. It is Safer: Deimos is also by far the safest small body for sample return yet imaged. It is an order of magnitude less rocky than Eros and the NEAR-Shoemaker mission succeeded in landing on Eros with a spacecraft not designed for landing and proximity maneuvering. Because of Viking imagery we already know a great deal about the surface roughness of Deimos. It is known to be very smooth and have moderate topography and

  1. Exploring the Processes of Self-Development Encountered by Adult Returners to Higher Education: A Lifespan Psychology Perspective

    ERIC Educational Resources Information Center

    Mercer, Jenny

    2010-01-01

    Evidence indicates that non-traditional adult returners describe returning to education as a period of self-development and growth. However, lifespan psychology perspectives also show that successful growth and change involves periods of conflict. This paper will explore both the nature of self-development and conflicts experienced by a sample of…

  2. Periodic Polymers

    NASA Astrophysics Data System (ADS)

    Thomas, Edwin

    2013-03-01

    Periodic polymers can be made by self assembly, directed self assembly and by photolithography. Such materials provide a versatile platform for 1, 2 and 3D periodic nano-micro scale composites with either dielectric or impedance contrast or both, and these can serve for example, as photonic and or phononic crystals for electromagnetic and elastic waves as well as mechanical frames/trusses. Compared to electromagnetic waves, elastic waves are both less complex (longitudinal modes in fluids) and more complex (longitudinal, transverse in-plane and transverse out-of-plane modes in solids). Engineering of the dispersion relation between wave frequency w and wave vector, k enables the opening of band gaps in the density of modes and detailed shaping of w(k). Band gaps can be opened by Bragg scattering, anti-crossing of bands and discrete shape resonances. Current interest is in our group focuses using design - modeling, fabrication and measurement of polymer-based periodic materials for applications as tunable optics and control of phonon flow. Several examples will be described including the design of structures for multispectral band gaps for elastic waves to alter the phonon density of states, the creation of block polymer and bicontinuous metal-carbon nanoframes for structures that are robust against ballistic projectiles and quasi-crystalline solid/fluid structures that can steer shock waves.

  3. Comet coma sample return via Giotto II

    NASA Technical Reports Server (NTRS)

    Tsou, P.; Brownlee, D. E.; Albee, A. L.

    1985-01-01

    A comet coma sample return is possible with a low-cost flyby mission. Collecting coma materials and returning them to earth can be accomplished in a free-return trajectory. Intact capture of coma dust, preserving the cometary dust mineralogy, is possible at low encounter speeds. Samples from a known cometary source can then be compared with the wealth of information on meteorites and interplanetary dust. Sample return via Giotto II is a unique, low-cost NASA/ESA cooperative opportunity. With ESA providing the Giotto spacecraft and payload and NASA the sample return capability, first-class science can be accomplished at a very low cost for both NASA and ESA. This paper focuses on the sample return aspects, including sample return objectives, sample collection techniques, experimental work to verify collection concepts, and some of the characteristics of the cometary targets for sample return.

  4. Evidence of Higher-Order Solar Periodicities in China Temperature Record

    NASA Astrophysics Data System (ADS)

    Tiwari, R. K.; Rajesh, R.; Padmavathi, B.

    2016-04-01

    We examine here a 2000-year-long record of surface air temperature from China using powerful spectral and statistical analysis techniques to assess the trend and harmonics, if any. Our analyses reveal statistically significant periodicities of order ~900 ± 50, ~480 ± 20, 340 ± 10, ~190 ± 10 and ~130 ± 5 years, which closely match with the known higher-order solar cycles. These periodicities are also similar to quasi-periodicities reported in the climate records of sedimentary cores of subarctic and subpolar regions of North America and North Pacific, thus attesting to the global signature of solar signals in temperature variability. A visual comparison of the temperature series shows that the nodes and antinodes of the underlying temperature variation also match with sunspot variations. We also compare the China temperature (CT) with temperature of northern and southern hemispheres of the past 1000 years. The study reveals strong correlation between the southern hemispheric temperatures and CT during the past 1000 years. However, the northern hemisphere temperature shows strong correlation with CT only during the past century. Interestingly, the variations in the correlation coefficient also have shown periodicities that are nearly identical to the periods observed from CT and higher-order solar cycles. We suggest that the solar irradiance induces global periodic oscillations in temperature records by transporting heat and thermal energy, possibly through the coupling of ocean-atmospheric processes and thereby reinforcing the Sun-ocean-climate link.

  5. Evidence of Higher-Order Solar Periodicities in China Temperature Record

    NASA Astrophysics Data System (ADS)

    Tiwari, R. K.; Rajesh, R.; Padmavathi, B.

    2016-07-01

    We examine here a 2000-year-long record of surface air temperature from China using powerful spectral and statistical analysis techniques to assess the trend and harmonics, if any. Our analyses reveal statistically significant periodicities of order ~900 ± 50, ~480 ± 20, 340 ± 10, ~190 ± 10 and ~130 ± 5 years, which closely match with the known higher-order solar cycles. These periodicities are also similar to quasi-periodicities reported in the climate records of sedimentary cores of subarctic and subpolar regions of North America and North Pacific, thus attesting to the global signature of solar signals in temperature variability. A visual comparison of the temperature series shows that the nodes and antinodes of the underlying temperature variation also match with sunspot variations. We also compare the China temperature (CT) with temperature of northern and southern hemispheres of the past 1000 years. The study reveals strong correlation between the southern hemispheric temperatures and CT during the past 1000 years. However, the northern hemisphere temperature shows strong correlation with CT only during the past century. Interestingly, the variations in the correlation coefficient also have shown periodicities that are nearly identical to the periods observed from CT and higher-order solar cycles. We suggest that the solar irradiance induces global periodic oscillations in temperature records by transporting heat and thermal energy, possibly through the coupling of ocean-atmospheric processes and thereby reinforcing the Sun-ocean-climate link.

  6. 5 CFR 1650.5 - Returned funds.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 3 2013-01-01 2013-01-01 false Returned funds. 1650.5 Section 1650.5 Administrative Personnel FEDERAL RETIREMENT THRIFT INVESTMENT BOARD METHODS OF WITHDRAWING FUNDS FROM THE THRIFT SAVINGS PLAN General § 1650.5 Returned funds. If a withdrawal is returned as undeliverable, the TSP...

  7. 5 CFR 1650.5 - Returned funds.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 3 2011-01-01 2011-01-01 false Returned funds. 1650.5 Section 1650.5 Administrative Personnel FEDERAL RETIREMENT THRIFT INVESTMENT BOARD METHODS OF WITHDRAWING FUNDS FROM THE THRIFT SAVINGS PLAN General § 1650.5 Returned funds. If a withdrawal is returned as undeliverable, the TSP...

  8. 5 CFR 1650.5 - Returned funds.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 5 Administrative Personnel 3 2012-01-01 2012-01-01 false Returned funds. 1650.5 Section 1650.5 Administrative Personnel FEDERAL RETIREMENT THRIFT INVESTMENT BOARD METHODS OF WITHDRAWING FUNDS FROM THE THRIFT SAVINGS PLAN General § 1650.5 Returned funds. If a withdrawal is returned as undeliverable, the TSP...

  9. 5 CFR 1650.5 - Returned funds.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 3 2010-01-01 2010-01-01 false Returned funds. 1650.5 Section 1650.5 Administrative Personnel FEDERAL RETIREMENT THRIFT INVESTMENT BOARD METHODS OF WITHDRAWING FUNDS FROM THE THRIFT SAVINGS PLAN General § 1650.5 Returned funds. If a withdrawal is returned as undeliverable, the TSP...

  10. 5 CFR 1650.5 - Returned funds.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 5 Administrative Personnel 3 2014-01-01 2014-01-01 false Returned funds. 1650.5 Section 1650.5 Administrative Personnel FEDERAL RETIREMENT THRIFT INVESTMENT BOARD METHODS OF WITHDRAWING FUNDS FROM THE THRIFT SAVINGS PLAN General § 1650.5 Returned funds. If a withdrawal is returned as undeliverable, the TSP...

  11. 50 CFR 12.51 - Return procedure.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 1 2010-10-01 2010-10-01 false Return procedure. 12.51 Section 12.51 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR TAKING... SEIZURE AND FORFEITURE PROCEDURES Return of Property § 12.51 Return procedure. If, at the conclusion...

  12. 21 CFR 203.23 - Returns.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Returns. 203.23 Section 203.23 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL PRESCRIPTION DRUG MARKETING Sales Restrictions § 203.23 Returns. The return of a prescription drug purchased...

  13. The Effects of Twitter Sentiment on Stock Price Returns

    PubMed Central

    Ranco, Gabriele; Aleksovski, Darko; Caldarelli, Guido; Grčar, Miha; Mozetič, Igor

    2015-01-01

    Social media are increasingly reflecting and influencing behavior of other complex systems. In this paper we investigate the relations between a well-known micro-blogging platform Twitter and financial markets. In particular, we consider, in a period of 15 months, the Twitter volume and sentiment about the 30 stock companies that form the Dow Jones Industrial Average (DJIA) index. We find a relatively low Pearson correlation and Granger causality between the corresponding time series over the entire time period. However, we find a significant dependence between the Twitter sentiment and abnormal returns during the peaks of Twitter volume. This is valid not only for the expected Twitter volume peaks (e.g., quarterly announcements), but also for peaks corresponding to less obvious events. We formalize the procedure by adapting the well-known “event study” from economics and finance to the analysis of Twitter data. The procedure allows to automatically identify events as Twitter volume peaks, to compute the prevailing sentiment (positive or negative) expressed in tweets at these peaks, and finally to apply the “event study” methodology to relate them to stock returns. We show that sentiment polarity of Twitter peaks implies the direction of cumulative abnormal returns. The amount of cumulative abnormal returns is relatively low (about 1–2%), but the dependence is statistically significant for several days after the events. PMID:26390434

  14. The Effects of Twitter Sentiment on Stock Price Returns.

    PubMed

    Ranco, Gabriele; Aleksovski, Darko; Caldarelli, Guido; Grčar, Miha; Mozetič, Igor

    2015-01-01

    Social media are increasingly reflecting and influencing behavior of other complex systems. In this paper we investigate the relations between a well-known micro-blogging platform Twitter and financial markets. In particular, we consider, in a period of 15 months, the Twitter volume and sentiment about the 30 stock companies that form the Dow Jones Industrial Average (DJIA) index. We find a relatively low Pearson correlation and Granger causality between the corresponding time series over the entire time period. However, we find a significant dependence between the Twitter sentiment and abnormal returns during the peaks of Twitter volume. This is valid not only for the expected Twitter volume peaks (e.g., quarterly announcements), but also for peaks corresponding to less obvious events. We formalize the procedure by adapting the well-known "event study" from economics and finance to the analysis of Twitter data. The procedure allows to automatically identify events as Twitter volume peaks, to compute the prevailing sentiment (positive or negative) expressed in tweets at these peaks, and finally to apply the "event study" methodology to relate them to stock returns. We show that sentiment polarity of Twitter peaks implies the direction of cumulative abnormal returns. The amount of cumulative abnormal returns is relatively low (about 1-2%), but the dependence is statistically significant for several days after the events. PMID:26390434

  15. Mars 2005 Sample Return Workshop

    NASA Technical Reports Server (NTRS)

    Gulick, V. C. (Editor)

    1997-01-01

    Convened at the request of Dr. Jurgen Rahe of the NASA Office of Space Science, the purpose of this workshop was to reexamine the science issues that will determine how an optimum sample return mission would be carried out in 2005 given the new context that has emerged for Mars exploration since the last such workshop was held (in 1987). The results and summary of discussion that took place at the meeting are contained in this volume. The community was invited to participate in the preparation of the final written report by browsing through the agenda and reading the text and viewgraphs provided by workshop participants and submitting comments for that section.

  16. Data link and return link

    NASA Astrophysics Data System (ADS)

    Meuron, Bruce R.; Lyons, Joseph B., Jr.

    1991-05-01

    This invention relates to a data coder, code searching mechanism, data decoder, and range computer for a missile wherein the missile receiver is able to discriminate between the real signals and jamming signals. The system provides discrimination in aircraft receiver systems for the return synchronization signal. This is accomplished by utilizing a random code generator wherein the command data signals modulate the code train which in turn modulates the RF carrier. The missile contains a second code generator with a code searching mechanism which synchronizes the second code generator with the first generator. The comparison of the second code generator signal with the received signal produces the command signal as an output.

  17. Mars rover sample return missions

    NASA Technical Reports Server (NTRS)

    Cunningham, Glenn E.; Rea, Donald G.; Pivirotto, Donna; Kwok, Johnny; Craig, Mark K.

    1988-01-01

    An important intermediate step in the path to human exploration of Mars is the accomplishment of a mission which lands an unmanned rover on the Martian surface, selects and collects various samples of the terrain and atmosphere, and returns them to earth for analysis. Such a mission is being developed under the management of NASA's JPL and the Johnson Space Center. The concepts for a wide range of rover capabilities are studied and an assessment of the driving technological developments required to implement these capabilities is made.

  18. Return to Flight Task Group

    NASA Technical Reports Server (NTRS)

    2005-01-01

    It has been 29 months since Columbia was lost over East Texas in February 2003. Seven months after the accident, the Columbia Accident Investigation Board (CAIB) released the first volume of its final report, citing a variety of technical, managerial, and cultural issues within NASA and the Space Shuttle Program. To their credit, NASA offered few excuses, embraced the report, and set about correcting the deficiencies noted by the accident board. Of the 29 recommendations issued by the CAIB, 15 were deemed critical enough that the accident board believed they should be implemented prior to returning the Space Shuttle to flight. Some of these recommendations were relatively easy, most were straightforward, a few bordered on the impossible, and others were largely overcome by events, particularly the decision by the President to retire the Space Shuttle by 2010. The Return to Flight Task Group (RTF TG, or simply, the Task Group) was chartered by the NASA Administrator in July 2003 to provide an independent assessment of the implementation of the 15 CAIB return-to-flight recommendations. An important observation must be stated up-front: neither the CAIB nor the RTF TG believes that all risk can be eliminated from Space Shuttle operations; nor do we believe that the Space Shuttle is inherently unsafe. What the CAIB and RTF TG do believe, however, is that NASA and the American public need to understand the risks associated with space travel, and that NASA must make every reasonable effort to minimize such risk. Since the release of the CAIB report, NASA and the Space Shuttle Program expended enormous effort and resources toward correcting the causes of the accident and preparing to fly again. Relative to the 15 specific recommendations that the CAIB indicated should be implemented prior to returning to flight, NASA has met or exceeded most of them the Task Group believes that NASA met the intent of the CAIB for 12 of these recommendations. The remaining three

  19. Return to Play After Lumbar Spine Surgery.

    PubMed

    Cook, Ralph W; Hsu, Wellington K

    2016-10-01

    Surgical management of lumbar spine conditions can produce excellent outcomes in athletes. Microdiscectomy for lumbar disc herniation has favorable outcomes; most athletes return to play at preoperative performance levels. Direct pars repair is successful in younger athletes, with high rates of return to play for a variety of fixation techniques. Fusion in athletes with scoliosis is a negative predictor. There are few evidence-based return to play criteria. Athletes should demonstrate full resolution of symptoms and flexibility, endurance, and strength before returning to play. Deciding when to return an athlete to sport depends on particular injury sustained, sport, and individual factors. PMID:27543402

  20. Low encounter speed comet COMA sample return missions

    NASA Technical Reports Server (NTRS)

    Tsou, P.; Yen, C. W.; Albee, A. L.

    1994-01-01

    Comets, being considered the most primitive bodies in the solar system, command the highest priority among solar-system objects for studying solar nebula evolution and the evolution of life through biogenic elements and compounds. The study of comets, and more especially, of material from them, provides an understanding of the physical, chemical, and mineralogical processes operative in the formation and earliest development of the solar systems. These return samples will provide valuable information on comets and serve as a rosetta stone for the analytical studies conducted on interplanetary dust particles over the past two decades, and will provide much needed extraterrestrial samples for the planetary materials community since the Apollo program. Lander sample return missions require rather complex spacecraft, intricate operations, and costly propulsion systems. By contrast, it is possible to take a highly simplified approach for sample capture and return in the case of a comet. In the past, we have considered Earth free-return trajectory to the comet, in which passive collectors intercept dust and volatiles from the cometary coma. However, standard short period cometary free-return trajectories results in the comet to the spacecraft encounter speeds in the range of 10 km/s. At these speeds the kinetic energy of the capture process can render significant modification of dust structure, change of solid phase as well as the lost of volatiles components. This paper presents a class of new missions with trajectories with significant reduction of encounter speeds by incorporating gravity assists and deep space maneuvering. Low encounter speed cometary flyby sample return will enable a marked increase in the value of the return science. Acquiring thousands of samples from a known comet and thousands of images of a comet nucleus would be space firsts. Applying new approach in flight mechanics to generate a new class of low encounter speed cometary sample return

  1. 26 CFR 1.6013-2 - Joint return after filing separate return.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... of the excess. (ii) If any part of such excess is attributable to fraud with intent to evade tax at... (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Tax Returns Or Statements § 1.6013-2 Joint return... which the tax based on the joint return has been paid. (2) If a joint return is made under section...

  2. 26 CFR 1.6013-2 - Joint return after filing separate return.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... of the excess. (ii) If any part of such excess is attributable to fraud with intent to evade tax at... (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Tax Returns Or Statements § 1.6013-2 Joint return... which the tax based on the joint return has been paid. (2) If a joint return is made under section...

  3. 26 CFR 1.6013-2 - Joint return after filing separate return.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... of the excess. (ii) If any part of such excess is attributable to fraud with intent to evade tax at... (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Tax Returns Or Statements § 1.6013-2 Joint return... which the tax based on the joint return has been paid. (2) If a joint return is made under section...

  4. 12 CFR 210.12 - Return of cash items and handling of returned checks.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... accounting entries) subject to this subpart and to the Reserve Banks' operating circulars. (2) Warranties for... the returned check, in paper or electronic form, for forward collection or return. (3) Warranties for all returned checks that are electronic items. A paying bank or returning bank that sends a...

  5. The dynamics of health and return migration.

    PubMed

    Davies, Anita A; Borland, Rosilyne M; Blake, Carolyn; West, Haley E

    2011-06-01

    The increasing importance and complexity of migration globally also implies a global increase in return migration, and thus an increased interest in the health of returning migrants. The health of returning migrants is impacted by the cumulative exposure to social determinants and risk factors of health during the migration process, during the return movement, and following return. Circular migration often occurs among the diaspora, which can result in the transfer of knowledge and skills that contribute to development, including health system strengthening. Migrants with dual nationality often return to countries with better health services than their country of origin when they are sick and can not get care at home. To maintain and improve the health of returning migrants, multi-sectoral policies at global and national levels should facilitate access to appropriate and equitable health services, social services, and continuity of care across and within borders. PMID:21738448

  6. Investigation of the effects of returning electrons on klystron performance

    NASA Astrophysics Data System (ADS)

    Roybal, William Thomas

    The klystron, as part of an RF distribution system for an accelerator, is one of the most important components contributing to the cost, reliability, and longevity of the overall system. Operating cost is one of the primary concerns for klystrons. Achieving high direct current (DC) to radio frequency (RF) conversion efficiency, free of instabilities is very important. There is uncertainty concerning the effects of returning electrons within the klystron and the impact that they have on klystron performance. The effects of reverse traveling electrons on klystron performance, such as efficiency, are poorly defined. Classical and even modern klystron design avoids the consideration of return electrons, and thus the effects have not been numerically analyzed and quantified. A better understanding of the electron beam-to-RF conversion process and the effects of return electrons within the klystron output circuit is needed. Accurate klystron modeling and simulation of return electron effects are required to better understand the implications of the problem. This analysis identifies the influence that returning electrons have on the overall beam dynamics and self-consistent cavity voltages. Closer examination of the harmonic content within the reverse beam current, along with comparison to the nominal klystron design, reveals the effects that reverse flowing electrons can have on klystron performance and design. The results of this work include a description of the electron beam dynamics for a beam decelerated in the output cavity, with separation occurring between forward and reverse electrons. Varying the output parameter of the klystron causes an unexpected response in return current quantity and bunching quality, yielding periodic correlations and responses to two-stream interaction.

  7. Hera: Multiple Near-Earth Asteroid Sample Return

    NASA Astrophysics Data System (ADS)

    Sears, D. W. G.; Brownlee, D. D.; Pieters, C.; Lindstrom, M. L.; Britt, D.; Clark, B. C.; Gefert, L.; Gorevan, S.; Preble, J. C.

    2000-10-01

    With the discovery of large numbers of Near-Earth Asteroids and the successful Deep Space 1 and Shoemaker NEAR missions, multiple sample return from NEA is now technically feasible. We have designed a mission to take three samples from three NEA and return them to Earth. The mission is named Hera, after the mother of the Three Graces. The target asteroids will be chosen on the basis of their spectra and the sampling sites will be chosen from orbit. Sufficient material will be returned for all qualified investigators to obtain samples. One trajectory identified to date is a follows. Hera would be launched on 15 Jan 2006 by a Boeing Delta 7925-10 and reach asteroids AO10 on 3 Aug 2006, 2000 AG6 on 10 Nov 2006, and 1989 UQ on 7 Mar 2009. Stay periods would be 99 days, 98 days and 205 days, respectively. Hera would return the samples to Earth on 13 Nov 2010 using Stardust procedures. Hera is equipped with gallium arsenide solar panels capable of producing 6 kWe, and three ion thrusters similar to those on Deep Space 1 (for deep space) and hydrazine thrusters (for asteroid operations). Hera's dryweight is 650 kg, and the fuel weight is 350 kg Xe and 60 kg hydrazine. The sampling device is an auger bit on a universal coupling housed inside a conical collector. The device is deployed without landing the spacecraft. Nine independent compartments house the samples for return. The amount and quality of science data produced by Hera will be higher than any mission since Apollo. The depth and breadth of analysis on Earth far exceeds that possible by in situ methods and samples can be archived for future research. Furthermore, seven of the eleven goals in the NASA Strategic Plan for Space Science can be uniquely addressed by Hera and the samples it returns. These involve a variety of fundamental planetary science issues, mitigation of impact effects, HEDS and resource utilization.

  8. 47 CFR 65.701 - Period of review.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 3 2010-10-01 2010-10-01 false Period of review. 65.701 Section 65.701 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES (CONTINUED) INTERSTATE RATE OF RETURN PRESCRIPTION PROCEDURES AND METHODOLOGIES Maximum Allowable Rates of Return § 65.701...

  9. Time-bound product returns and optimal order quantities for mass merchandisers

    NASA Astrophysics Data System (ADS)

    Yu, Min-Chun; Goh, Mark

    2012-01-01

    The return guidelines for a mass merchandiser usually entail a grace period, a markdown on the original price and the condition of the returned items. This research utilises eight scenarios formed from the variation of possible return guidelines to model the cost functions of single-product categories for a typical mass merchandiser. Models for the eight scenarios are developed and solved with the objective of maximising the expected profit so as to obtain closed form solutions for the associated optimal order quantity. An illustrative example and sensitivity analysis are provided to demonstrate the applicability of the model. Our results show that merchandisers who allow for returns within a time window, albeit with a penalty cost imposed and the returned products being recoverable, should plan for larger order amounts as such products do not affect the business. Similarly, the merchandisers who allow for returns beyond a grace period and without any penalty charges, but where the returned products are irrecoverable, should manage their stocks in this category more judiciously by ordering as little as possible so as to limit the number of returns and carefully consider the effects of their customer satisfaction-guaranteed policies, if any.

  10. Orbiter Atlantis returns to KSC

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Stairs are rolled to the forward opening of the Shuttle Carrier Aircraft -- with its piggyback cargo, the orbiter Atlantis -- after it rolls to a stop at the Shuttle Landing Facility. Atlantis returns home after a 10-month stay in the Palmdale, CA, orbiter processing facility undergoing extensive inspections and modifications. They included several upgrades enabling it to support International Space Station missions, such as adding an external airlock for ISS docking missions and installing thinner, lighter thermal protection blankets for weight reduction which will allow it to haul heavier cargo. The flight from Palmdale included a fueling stop in Ft. Hood, TX, and overnight stay at Ft. Campbell, KY. Atlantis will undergo preparations in the Orbiter Processing Facility at KSC for its planned flight in June 1999.

  11. Sepsis, venous return, and teleology.

    PubMed

    McNeilly, R G

    2014-11-01

    An understanding of heart-circulation interaction is crucial to our ability to guide our patients through an episode of septic shock. Our knowledge has advanced greatly in the last one hundred years. There are, however, certain empirical phenomena that may lead us to question the wisdom of our prevailing treatment algorithm. Three extreme but iatrogenically possible haemodynamic states exist. Firstly, inappropriately low venous return; secondly, overzealous arteriolar constriction; and finally, misguided inotropy and chronotropy. Following an unsuccessful fluid challenge, it would be logical to first set the venous tone, then set the cardiac rate and contractility, and finally set the peripheral vascular resistance. It is hypothesized that a combination of dihydroergotamine, milrinone and esmolol should be superior to a combination of noradrenaline and dobutamine for surviving sepsis. PMID:25245463

  12. Partial Return Yoke for MICE

    SciTech Connect

    Witte H.; Plate, S

    2013-05-03

    The international Muon Ionization Cooling Experiment (MICE) is a large scale experiment which is presently assembled at the Rutherford Appleton Laboratory in Didcot, UK. The purpose of MICE is to demonstrate the concept of ionization cooling experimentally. Ionization cooling is an important accelerator concept which will be essential for future HEP experiments such as a potential Muon Collider or a Neutrino Factory. The MICE experiment will house up to 18 superconducting solenoids, all of which produce a substantial amount of magnetic flux. Recently it was realized that this magnetic flux leads to a considerable stray magnetic field in the MICE hall. This is a concern as technical equipment in the MICE hall may may be compromised by this. In July 2012 a concept called partial return yoke was presented to the MICE community, which reduces the stray field in the MICE hall to a safe level. This report summarizes the general concept, engineering considerations and the expected shielding performance.

  13. Risk analysis of earth return options for the Mars rover/sample return mission

    NASA Technical Reports Server (NTRS)

    1988-01-01

    Four options for return of a Mars surface sample to Earth were studied to estimate the risk of mission failure and the risk of a sample container breach that might result in the release of Martian life forms, should such exist, in the Earth's biosphere. The probabilities calculated refer only to the time period from the last midcourse correction burn to possession of the sample on Earth. Two extreme views characterize this subject. In one view, there is no life on Mars, therefore there is no significant risk and no serious effort is required to deal with back contamination. In the other view, public safety overrides any desire to return Martian samples, and any risk of damaging contamination greater than zero is unacceptable. Zero risk requires great expense to achieve and may prevent the mission as currently envisioned from taking place. The major conclusion is that risk of sample container breach can be reduced to a very low number within the framework of the mission as now envisioned, but significant expense and effort, above that currently planned is needed. There are benefits to the public that warrant some risk. Martian life, if it exists, will be a major discovery. If it does not, there is no risk.

  14. Sample Returns Missions in the Coming Decade

    NASA Technical Reports Server (NTRS)

    Desai, Prasun N.; Mitcheltree, Robert A.; Cheatwood, F. McNeil

    2000-01-01

    In the coming decade, several missions will attempt to return samples to Earth from varying parts of the solar system. These samples will provide invaluable insight into the conditions present during the early formation of the solar system, and possibly give clues to how life began on Earth. A description of five sample return missions is presented (Stardust, Genesis, Muses-C. Mars Sample Return, and Comet Nucleus Sample Return). An overview of each sample return mission is given, concentrating particularly on the technical challenges posed during the Earth entry, descent, and landing phase of the missions. Each mission faces unique challenges in the design of an Earth entry capsule. The design of the entry capsule must address the aerodynamic, heating, deceleration, landing, and recovery requirements for the safe return of samples to Earth.

  15. Return to sport after ACL reconstruction.

    PubMed

    Harris, Joshua D; Abrams, Geoffrey D; Bach, Bernard R; Williams, Donna; Heidloff, Dave; Bush-Joseph, Charles A; Verma, Nikhil N; Forsythe, Brian; Cole, Brian J

    2014-02-01

    Objective guidelines permitting safe return to sport following anterior cruciate ligament (ACL) reconstruction are infrequently used. The purpose of this study was to determine the published return to sport guidelines following ACL reconstruction in Level I randomized controlled trials. A systematic review was performed using Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. Level I randomized controlled trials were included if they reported a minimum 2-year follow-up after ACL reconstruction and return to sport criteria. Outcomes analyzed were the timing of initiation of return to sport, follow-up duration, and use of quantitative/qualitative criteria to determine return to sport. Forty-nine studies were included (N=4178; 68% male; mean patient age, 27.5±3.2 years; mean follow-up, 3.0±1.9 years; mean time from injury to reconstruction, 379±321 days). Ninety-six percent of reconstructions used autograft and 87% were single-bundle reconstructions. Lysholm score, single-leg hop, isokinetic strength, and KT-1000 or KT-2000 arthrometer (MEDmetric, San Diego, California) testing were performed in 67%, 31%, 31%, and 82% of studies, respectively. Only 5 studies reported whether patients were able to successfully return to sport. Ninety percent and 65% of studies failed to use objective criteria or any criteria, respectively, to permit return to sport. Description of permission/allowance to return to sport was highly variable and poor. Twenty-four percent of studies failed to report when patients were allowed return to sport without restrictions. Overall, 39%, 45%, and 51% of studies permitted running at 3 months, return to cutting/pivoting sports at 6 months, and return to sport without restrictions at 6 months, respectively. Further research into validated return to sport guidelines is necessary to fill the existing void in contemporary literature and to guide clinical practice. PMID:24679194

  16. 26 CFR 20.6018-3 - Returns; contents of returns.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...) period after the date of the decedent's death, together with the dates thereof; and (iii) the value of... AND GIFT TAXES ESTATE TAX; ESTATES OF DECEDENTS DYING AFTER AUGUST 16, 1954 Procedure and... decedent who was a citizen or resident of the United States at the time of his death must contain...

  17. 26 CFR 20.6018-3 - Returns; contents of returns.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...) period after the date of the decedent's death, together with the dates thereof; and (iii) the value of... AND GIFT TAXES ESTATE TAX; ESTATES OF DECEDENTS DYING AFTER AUGUST 16, 1954 Procedure and... decedent who was a citizen or resident of the United States at the time of his death must contain...

  18. 26 CFR 20.6018-3 - Returns; contents of returns.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...) period after the date of the decedent's death, together with the dates thereof; and (iii) the value of... AND GIFT TAXES ESTATE TAX; ESTATES OF DECEDENTS DYING AFTER AUGUST 16, 1954 Procedure and... decedent who was a citizen or resident of the United States at the time of his death must contain...

  19. What stock market returns to expect for the future?

    PubMed

    Diamond, P A

    2000-01-01

    In evaluating proposals for reforming Social Security that involve stock investments, the Office of the Chief Actuary (OCACT) has generally used a 7.0 percent real return for stocks. The 1994-96 Advisory Council specified that OCACT should use that return in making its 75-year projections of investment-based reform proposals. The assumed ultimate real return on Treasury bonds of 3.0 percent implies a long-run equity premium of 4.0 percent. There are two equity-premium concepts: the realized equity premium, which is measured by the actual rates of return; and the required equity premium, which investors expect to receive for being willing to hold available stocks and bonds. Over the past two centuries, the realized premium was 3.5 percent on average, but 5.2 percent for 1926 to 1998. Some critics argue that the 7.0 percent projected stock returns are too high. They base their arguments on recent developments in the capital market, the current high value of the stock market, and the expectation of slower economic growth. Increased use of mutual funds and the decline in their costs suggest a lower required premium, as does the rising fraction of the American public investing in stocks. The size of the decrease is limited, however, because the largest cost savings do not apply to the very wealthy and to large institutional investors, who hold a much larger share of the stock market's total value than do new investors. These trends suggest a lower equity premium for projections than the 5.2 percent of the past 75 years. Also, a declining required premium is likely to imply a temporary increase in the realized premium because a rising willingness to hold stocks tends to increase their price. Therefore, it would be a mistake during a transition period to extrapolate what may be a temporarily high realized return. In the standard (Solow) economic growth model, an assumption of slower long-run growth lowers the marginal product of capital if the savings rate is constant

  20. Illness in the Returned International Traveler.

    PubMed

    Sanford, Christopher A; Fung, Claire

    2016-03-01

    Familiarity with the distribution, mode of transmission, and risk factors for acquisition of illnesses commonly transmitted to travelers to low-income nations can help guide clinicians in their work-up of an ill returned traveler. The 3 most common categories of illness in returned international travelers are gastrointestinal illness, fever, and dermatoses. Diarrhea is the most common illness reported in returned international travelers. Fever is a marker of a potentially significant illness; work-up of the ill febrile returned traveler should be conducted promptly. PMID:26900121

  1. A Community Returns to Agriculture

    ERIC Educational Resources Information Center

    Saavedra-Vela, Pilar

    1978-01-01

    Aiming to keep the land in the hands of the people, the Cooperativa del pueblo's first venture of steer grazing on land held communally was abandoned due to financial pressure and the community's social needs. Today its plans include teaching families to grow vegetables for longer periods in an organic manner and developing a marketing…

  2. 12 CFR 210.12 - Return of cash items and handling of returned checks.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Bank, and any other Reserve Bank or returning bank to which the returned check is sent, to handle the... paragraph (c)(3) of this section. (h) Reserve Bank's responsibility. A Reserve Bank shall handle a...

  3. [Knowledge of Man Returns: Some Considerations on Spirituality and Resilience].

    PubMed

    Kumakura, Nobuhiro

    2015-01-01

    Over the last decade,"spirituality" and "resilience" have jointly become a topic in psychiatry. The aim of this paper is to discuss the future of psychiatry suggested by this topic. It may be related to what Jaspers, K. called "Knowledge of Man (die Erkenntnis des Menschen)". Knowledge of man in psychiatry can be learned only through clinical experince: e. g., clinical observations and case studies. Modern academic psychiatry seems to be suffering a loss of knowledge of man, which returns periodically in clinical practice. Hence, I will call the re-discovery of the topic in psychiatry as "Return of Man". Since WW II, there have been three eras in which psychiatrists showed deep concern regarding knowledge of man. Firstly, psychopathology and psychotherapy widely developed, when the destructive impulses of mankind were revealed in the nuclear weapons of WW II. Secondly, in the 1970's, the reforms of psychiatric services and legal systems took place somewhat successfully, when social reforms were concerns of the younger generations. Lastly, over the last decade, the topic again returned as spirituality and resilience, when scientists seemed to be powerless in the aftermath of the West Japan Earthquake. Regarding the definition of health made by the WHO in 1946, I further discuss that "Return of Man" in psychiatry is the necessary dynamism between negative and positive health, or between disease control and health promotion. There is an underlying dynamism between "Knowledge of Man" and natural sciences, which is constantly changing. So long as any theory can exist only as a part of dynamism, the Return of Man may re-surface whenever clinical theories do not fit with clinical realities. PMID:26642730

  4. 26 CFR 50.7 - Returns.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...) REGULATIONS RELATING TO THE TAX IMPOSED WITH RESPECT TO CERTAIN HYDRAULIC MINING § 50.7 Returns. (a) Form of... on which hydraulic mining operations began and ended during the taxable year for which the return is made; (7) The number of cubic yards mined by the hydraulic process at the mine during the taxable...

  5. 26 CFR 50.7 - Returns.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...) REGULATIONS RELATING TO THE TAX IMPOSED WITH RESPECT TO CERTAIN HYDRAULIC MINING § 50.7 Returns. (a) Form of... on which hydraulic mining operations began and ended during the taxable year for which the return is made; (7) The number of cubic yards mined by the hydraulic process at the mine during the taxable...

  6. 26 CFR 50.7 - Returns.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...) REGULATIONS RELATING TO THE TAX IMPOSED WITH RESPECT TO CERTAIN HYDRAULIC MINING § 50.7 Returns. (a) Form of... on which hydraulic mining operations began and ended during the taxable year for which the return is made; (7) The number of cubic yards mined by the hydraulic process at the mine during the taxable...

  7. 26 CFR 50.7 - Returns.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...) REGULATIONS RELATING TO THE TAX IMPOSED WITH RESPECT TO CERTAIN HYDRAULIC MINING § 50.7 Returns. (a) Form of... on which hydraulic mining operations began and ended during the taxable year for which the return is made; (7) The number of cubic yards mined by the hydraulic process at the mine during the taxable...

  8. 27 CFR 41.112 - Tax return.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Tax return. 41.112 Section 41.112 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF... States Deferred Payment of Tax in Puerto Rico on Tobacco Products § 41.112 Tax return. The...

  9. Returned Solar Max hardware degradation study results

    NASA Technical Reports Server (NTRS)

    Triolo, Jack J.; Ousley, Gilbert W.

    1989-01-01

    The Solar Maximum Repair Mission returned with the replaced hardware that had been in low Earth orbit for over four years. The materials of this returned hardware gave the aerospace community an opportunity to study the realtime effects of atomic oxygen, solar radiation, impact particles, charged particle radiation, and molecular contamination. The results of these studies are summarized.

  10. 46 CFR 308.514 - Return premium.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false Return premium. 308.514 Section 308.514 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE War Risk Cargo Insurance Ii-Open Policy War Risk Cargo Insurance § 308.514 Return premium. No premium will...

  11. Anxiety and the Newly Returned Adult Student

    ERIC Educational Resources Information Center

    Cleary, Michelle Navarre

    2012-01-01

    Based on interviews with students who had recently returned to school, this essay demonstrates the need for, challenges of, and ways to respond to the writing anxiety many adults bring with them back to school. Jessica and Sam were two of twenty-five newly returned adult students whom the author spent over sixty hours interviewing in the fall of…

  12. 7 CFR 356.8 - Return procedure.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 5 2012-01-01 2012-01-01 false Return procedure. 356.8 Section 356.8 Agriculture Regulations of the Department of Agriculture (Continued) ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE FORFEITURE PROCEDURES § 356.8 Return procedure. If, at the conclusion...

  13. Aggregate Unemployment Decreases Individual Returns to Education

    ERIC Educational Resources Information Center

    Ammermueller, Andreas; Kuckulenz, Anja; Zwick, Thomas

    2009-01-01

    Aggregate unemployment may affect individual returns to education through qualification-specific responses in participation and wage bargaining. This paper shows that an increase in regional unemployment by 1% decreases returns to education by 0.005 percentage points. This implies that higher skilled employees are better sheltered from labour…

  14. 46 CFR 308.514 - Return premium.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 8 2014-10-01 2014-10-01 false Return premium. 308.514 Section 308.514 Shipping... Cargo Insurance Open Policy War Risk Cargo Insurance § 308.514 Return premium. No premium will be... in the computation of a premium, or the insured goods were short-shipped. An application for...

  15. 46 CFR 308.514 - Return premium.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 8 2013-10-01 2013-10-01 false Return premium. 308.514 Section 308.514 Shipping... Cargo Insurance Ii-Open Policy War Risk Cargo Insurance § 308.514 Return premium. No premium will be... in the computation of a premium, or the insured goods were short-shipped. An application for...

  16. 26 CFR 50.7 - Returns.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) REGULATIONS RELATING TO THE TAX IMPOSED WITH RESPECT TO CERTAIN HYDRAULIC MINING § 50.7 Returns. (a) Form of... on which hydraulic mining operations began and ended during the taxable year for which the return is made; (7) The number of cubic yards mined by the hydraulic process at the mine during the taxable...

  17. The point of no return: A fundamental limit on the ability to control thought and action.

    PubMed

    Logan, Gordon D

    2015-01-01

    Bartlett (1958. Thinking. New York: Basic Books) described the point of no return as a point of irrevocable commitment to action, which was preceded by a period of gradually increasing commitment. As such, the point of no return reflects a fundamental limit on the ability to control thought and action. I review the literature on the point of no return, taking three perspectives. First, I consider the point of no return from the perspective of the controlled act, as a locus in the architecture and anatomy of the underlying processes. I review experiments from the stop-signal paradigm that suggest that the point of no return is located late in the response system. Then I consider the point of no return from the perspective of the act of control that tries to change the controlled act before it becomes irrevocable. From this perspective, the point of no return is a point in time that provides enough "lead time" for the act of control to take effect. I review experiments that measure the response time to the stop signal as the lead time required for response inhibition in the stop-signal paradigm. Finally, I consider the point of no return in hierarchically controlled tasks, in which there may be many points of no return at different levels of the hierarchy. I review experiments on skilled typing that suggest different points of no return for the commands that determine what is typed and the countermands that inhibit typing, with increasing commitment to action the lower the level in the hierarchy. I end by considering the point of no return in perception and thought as well as action. PMID:25633089

  18. 26 CFR 1.6033-1 - Returns by exempt organizations; taxable years beginning before January 1, 1970.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... is related by blood, marriage, adoption, or employment (including children of employees) to any... a refund of income taxes paid for the period for which its exempt status is established. (d) Group..., in addition to such separate annual return, a group return on Form 990 or 990-A, 990 (SF), or...

  19. Are Returns to Education on the Decline in Venezuela and Does Mission Sucre Have a Role to Play?

    ERIC Educational Resources Information Center

    Gonzalez, Naihobe; Oyelere, Ruth Uwaifo

    2011-01-01

    Anecdotal evidence points to a falling standard of living for the educated in Venezuela. During this same period, President Hugo Chavez implemented several education reforms. We focus on a major university education reform known as Mission Sucre and its potential impact on returns to university education. First, we show that returns to education…

  20. 26 CFR 1.6042-1 - Return of information as to dividends paid in calendar years before 1963.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... firm which prepares the individual income tax return of the actual owner, provided the verification on... tax on nonresident foreign corporations. (d) Time and place for filing. Returns made under this... shareholder” includes periodical distributions of earnings on running installment shares of stock paid...

  1. 26 CFR 1.6042-1 - Return of information as to dividends paid in calendar years before 1963.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... firm which prepares the individual income tax return of the actual owner, provided the verification on... tax on nonresident foreign corporations. (d) Time and place for filing. Returns made under this... shareholder” includes periodical distributions of earnings on running installment shares of stock paid...

  2. 26 CFR 1.6042-1 - Return of information as to dividends paid in calendar years before 1963.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... firm which prepares the individual income tax return of the actual owner, provided the verification on... tax on nonresident foreign corporations. (d) Time and place for filing. Returns made under this... shareholder” includes periodical distributions of earnings on running installment shares of stock paid...

  3. Maximizing your return on people.

    PubMed

    Bassi, Laurie; McMurrer, Daniel

    2007-03-01

    Though most traditional HR performance metrics don't predict organizational performance, alternatives simply have not existed--until now. During the past ten years, researchers Laurie Bassi and Daniel McMurrer have worked to develop a system that allows executives to assess human capital management (HCM) and to use those metrics both to predict organizational performance and to guide organizations' investments in people. The new framework is based on a core set of HCM drivers that fall into five major categories: leadership practices, employee engagement, knowledge accessibility, workforce optimization, and organizational learning capacity. By employing rigorously designed surveys to score a company on the range of HCM practices across the five categories, it's possible to benchmark organizational HCM capabilities, identify HCM strengths and weaknesses, and link improvements or back-sliding in specific HCM practices with improvements or shortcomings in organizational performance. The process requires determining a "maturity" score for each practice, based on a scale of 1 (low) to 5 (high). Over time, evolving maturity scores from multiple surveys can reveal progress in each of the HCM practices and help a company decide where to focus improvement efforts that will have a direct impact on performance. The authors draw from their work with American Standard, South Carolina's Beaufort County School District, and a bevy of financial firms to show how improving HCM scores led to increased sales, safety, academic test scores, and stock returns. Bassi and McMurrer urge HR departments to move beyond the usual metrics and begin using HCM measurement tools to gauge how well people are managed and developed throughout the organization. In this new role, according to the authors, HR can take on strategic responsibility and ensure that superior human capital management becomes central to the organization's culture. PMID:17348175

  4. The OSIRIS-REx Asteroid Sample Return Mission Operations Design

    NASA Technical Reports Server (NTRS)

    Gal-Edd, Jonathan S.; Cheuvront, Allan

    2015-01-01

    OSIRIS-REx is an acronym that captures the scientific objectives: Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer. OSIRIS-REx will thoroughly characterize near-Earth asteroid Bennu (Previously known as 1019551999 RQ36). The OSIRIS-REx Asteroid Sample Return Mission delivers its science using five instruments and radio science along with the Touch-And-Go Sample Acquisition Mechanism (TAGSAM). All of the instruments and data analysis techniques have direct heritage from flown planetary missions. The OSIRIS-REx mission employs a methodical, phased approach to ensure success in meeting the mission's science requirements. OSIRIS-REx launches in September 2016, with a backup launch period occurring one year later. Sampling occurs in 2019. The departure burn from Bennu occurs in March 2021. On September 24, 2023, the Sample Return Capsule (SRC) lands at the Utah Test and Training Range (UTTR). Stardust heritage procedures are followed to transport the SRC to Johnson Space Center, where the samples are removed and delivered to the OSIRIS-REx curation facility. After a six-month preliminary examination period the mission will produce a catalog of the returned sample, allowing the worldwide community to request samples for detailed analysis. Traveling and returning a sample from an Asteroid that has not been explored before requires unique operations consideration. The Design Reference Mission (DRM) ties together spacecraft, instrument and operations scenarios. Asteroid Touch and Go (TAG) has various options varying from ground only to fully automated (natural feature tracking). Spacecraft constraints such as thermo and high gain antenna pointing impact the timeline. The mission is sensitive to navigation errors, so a late command update has been implemented. The project implemented lessons learned from other "small body" missions. The key lesson learned was 'expect the unexpected' and implement planning tools early in the lifecycle

  5. Quality of the Arkansas River and irrigation-return flows in the lower Arkansas River Valley, Colorado

    USGS Publications Warehouse

    Cain, Doug

    1985-01-01

    Irrigation-return flows in the lower Arkansas River valley of Colorado were investigated using one-time data at 59 sites, monthly data at 4 sites, and intensive data in a small irrigated area. Specific conductance of return flows increased downstream, paralleling specific conductance of irrigation water. During July 1977, Arkansas River streamflow below Manzanola was mostly irrigation-return flow. A similar situation existed during periods of little precipitation in the early and late irrigation seasons during 1974 to 1978. Irrigation-return flows had a large effect on Arkansas River water quality during these times. (USGS)

  6. Mars sample return: The critical next step

    NASA Astrophysics Data System (ADS)

    Clark, Benton C.

    2007-06-01

    Before humans trek the mountains and canyons of Mars, a key event must happen. That vital undertaking will be to fly a roundtrip mission to Mars for acquiring representative surface materials and returning them to Earth. Mars sample return has also been a premier objective of planetary scientists for more than four decades. In the meantime, the Stardust mission has returned dust grains from a comet, and Genesis has collected and returned solar wind. Yet at this time, Mars sample return is no longer an official project in any space agency. Inestimable value would also accrue for engineering the systems needed for future human missions. Sample return from the surface will validate our collective ability to successfully accomplish such a roundtrip to Mars in absence of the ability for end-to-end testing on Earth. Embarking on a historic Mars surface sample return mission will provide the confirming signal that a space program is ready, willing, and capable to achieve the next major engineering challenge for exploration of our solar system. Beginning serious development of the missing critical link, the Mars Ascent Vehicle, will signal the beginning of this undertaking.

  7. Integrating public perspectives in sample return planning.

    PubMed

    Race, M S; MacGregor, D G

    2000-01-01

    Planning for extraterrestrial sample returns--whether from Mars or other solar system bodies--must be done in a way that integrates planetary protection concerns with the usual mission technical and scientific considerations. Understanding and addressing legitimate societal concerns about the possible risks of sample return will be a critical part of the public decision making process ahead. This paper presents the results of two studies, one with lay audiences, the other with expert microbiologists designed to gather information on attitudes and concerns about sample return risks and planetary protection. Focus group interviews with lay subjects, using generic information about Mars sample return and a preliminary environmental impact assessment, were designed to obtain an indication of how the factual content is perceived and understood by the public. A research survey of microbiologists gathered information on experts' views and attitudes about sample return, risk management approaches and space exploration risks. These findings, combined with earlier research results on risk perception, will be useful in identifying levels of concern and potential conflicts in understanding between experts and the public about sample return risks. The information will be helpful in guiding development of the environmental impact statement and also has applicability to proposals for sample return from other solar system bodies where scientific uncertainty about extraterrestrial life may persist at the time of mission planning. PMID:12038482

  8. Integrating Public Perspectives in Sample Return Planning

    NASA Technical Reports Server (NTRS)

    Race, Margaret S.; MacGregor, G.

    2001-01-01

    Planning for extraterrestrial sample returns, whether from Mars or other solar system bodies, must be done in a way that integrates planetary protection concerns with the usual mission technical and scientific considerations. Understanding and addressing legitimate societal concerns about the possible risks of sample return will be a critical part of the public decision making process ahead. This paper presents the results of two studies, one with lay audiences, the other with expert microbiologists, designed to gather information, on attitudes and concerns about sample return risks and planetary protection. Focus group interviews with lay subjects, using generic information about Mars sample return and a preliminary environmental impact assessment, were designed to obtain an indication of how the factual content is perceived and understood by the public. A research survey of microbiologists gathered information on experts' views and attitudes about sample return, risk management approaches and space exploration risks. These findings, combined with earlier research results on risk perception, will be useful in identifying levels of concern and potential conflicts in understanding between experts and the public about sample return risks. The information will be helpful in guiding development of the environmental impact statement and also has applicability to proposals for sample return from other solar system bodies where scientific uncertainty about extraterrestrial life may persist at the time of mission planning.

  9. Technology for return of planetary samples

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Technological requirements of a planetary return sample mission were studied. The state-of-the-art for problems unique to this class of missions was assessed and technological gaps were identified. The problem areas where significant advancement of the state-of-the-art is required are: life support for the exobiota during the return trip and within the Planetary Receiving Laboratory (PRL); biohazard assessment and control technology; and quarantine qualified handling and experimentation methods and equipment for studying the returned sample in the PRL. Concepts for solving these problems are discussed.

  10. Return to Play Following Hip Arthroscopy.

    PubMed

    Lee, Simon; Kuhn, Andrew; Draovitch, Pete; Bedi, Asheesh

    2016-10-01

    Femoroacetabular impingement may be particularly disabling to the high-demand athlete, especially those with significant cutting and pivoting requirements. If nonoperative treatment fails to adequately alleviate symptoms or sufficiently restore function in the athlete, hip arthroscopy can lead to improved pain, improved range of motion, and high rates of return to play with proper postoperative rehabilitation. The rate of return to previous level of competition is also high with accurate diagnosis and well-executed correction of deformity. A clear understanding of the etiology, diagnosis, management, and outcomes is essential for clinicians to optimally help patients to return to play. PMID:27543404

  11. GEOS-1 laser pulse return shape analysis

    NASA Technical Reports Server (NTRS)

    Felsentreger, T. L.

    1972-01-01

    An attempt has been made to predict the shape of the laser return pulse from the corner cube retroreflectors on the GEOS-1 spacecraft. The study is geometrical only, and neglects factors such as optical interference, atmospheric perturbations, etc. A function giving the intensity of the return signal at any given time has been derived. In addition, figures are given which show the predicted return pulse shape as a function of time, the angle between the beam and the spin axis, and an in-plane angle (designating the orientation of the intersection of the planar waves with the plane of the corner cubes).

  12. Winged cargo return vehicle conceptual design

    NASA Technical Reports Server (NTRS)

    1990-01-01

    NASA is committed to placing a permanent space station in Earth orbit in the 1990's. Space Station Freedom (SSF) will be located in a 220 n.m. orbit at 28.5 degrees inclination. The Winged Cargo Return Vehicle's (CRV) primary mission is to support SSF crew by flying regular resupply missions. The winged CRV is designed to be reusable, dry land recoverable, and unmanned. The CRV will be launched inline on three liquid hydrogen/oxygen rocket boosters with a payload capacity of 113,000 lbs. The three boosters will take the CRV to an orbit of 50 by 110 n.m. From this altitude the orbital manuevering engine will place the vehicle in synchronous orbit with the space station. The winged CRV will deliver cargo modules to the space station by direct docking or by remaining outside the SSF command zone and using the Orbital Maneuvering Vehicle (OMV) to transfer cargo. After unloading/loading, the CRV will deorbit and fly back to Kennedy Space Center. The CRV has a wing span of 57.8 feet, a length of 76.0 feet, and a dry weight of 61.5 klb. The cargo capacity of the vehicle is 44.4 klb. The vehicle has a lift-drag ratio of 1.28 (hypersonic) and 6.0 (subsonic), resulting in a 1351 n.m. cross range. The overall mission length ranges between 18.8 and 80.5 hr. The operational period will be the years 2000 to 2020.

  13. Sample Tube Sealing for Future Proposed Mars Sample Return Missions

    NASA Technical Reports Server (NTRS)

    Younse, P.; Aveline, D.; Bao, X.; Berisford, D.; Bhandari, P.; Budney, C.; Chen, F.; Cooper, M.; Chung, S.; Lewis, D.

    2013-01-01

    A key premise of a proposed Sample Caching Rover, a crucial element of the proposed Mars Sample Return (MSR) campaign, is that the samples could be packaged and left on Mars for an extended period of time (at least five Mars years) without loss of scientific value (Fig. 1). The MEPAG E2E-iSAG (2011) concluded that the single most important factor in preserving the scientific integrity of the samples during the interval between their collection and their analysis is effective sealing of the samples.

  14. An efficient approach for Mars Sample Return using emerging commercial capabilities

    NASA Astrophysics Data System (ADS)

    Gonzales, Andrew A.; Stoker, Carol R.

    2016-06-01

    Mars Sample Return is the highest priority science mission for the next decade as recommended by the 2011 Decadal Survey of Planetary Science (Squyres, 2011 [1]). This article presents the results of a feasibility study for a Mars Sample Return mission that efficiently uses emerging commercial capabilities expected to be available in the near future. The motivation of our study was the recognition that emerging commercial capabilities might be used to perform Mars Sample Return with an Earth-direct architecture, and that this may offer a desirable simpler and lower cost approach. The objective of the study was to determine whether these capabilities can be used to optimize the number of mission systems and launches required to return the samples, with the goal of achieving the desired simplicity. All of the major element required for the Mars Sample Return mission are described. Mission system elements were analyzed with either direct techniques or by using parametric mass estimating relationships. The analysis shows the feasibility of a complete and closed Mars Sample Return mission design based on the following scenario: A SpaceX Falcon Heavy launch vehicle places a modified version of a SpaceX Dragon capsule, referred to as "Red Dragon", onto a Trans Mars Injection trajectory. The capsule carries all the hardware needed to return to Earth Orbit samples collected by a prior mission, such as the planned NASA Mars 2020 sample collection rover. The payload includes a fully fueled Mars Ascent Vehicle; a fueled Earth Return Vehicle, support equipment, and a mechanism to transfer samples from the sample cache system onboard the rover to the Earth Return Vehicle. The Red Dragon descends to land on the surface of Mars using Supersonic Retropropulsion. After collected samples are transferred to the Earth Return Vehicle, the single-stage Mars Ascent Vehicle launches the Earth Return Vehicle from the surface of Mars to a Mars phasing orbit. After a brief phasing period, the

  15. Fluctuation behaviors of financial return volatility duration

    NASA Astrophysics Data System (ADS)

    Niu, Hongli; Wang, Jun; Lu, Yunfan

    2016-04-01

    It is of significantly crucial to understand the return volatility of financial markets because it helps to quantify the investment risk, optimize the portfolio, and provide a key input of option pricing models. The characteristics of isolated high volatility events above certain threshold in price fluctuations and the distributions of return intervals between these events arouse great interest in financial research. In the present work, we introduce a new concept of daily return volatility duration, which is defined as the shortest passage time when the future volatility intensity is above or below the current volatility intensity (without predefining a threshold). The statistical properties of the daily return volatility durations for seven representative stock indices from the world financial markets are investigated. Some useful and interesting empirical results of these volatility duration series about the probability distributions, memory effects and multifractal properties are obtained. These results also show that the proposed stock volatility series analysis is a meaningful and beneficial trial.

  16. Returning to sports after a back injury

    MedlinePlus

    ... to return to the sport with your doctor, physical therapist, or other health care providers? Have you been ... sport, talk to your health care provider and physical therapist about whether you can do this safely. Contact ...

  17. Analysis and representation of sonar echo returns

    NASA Astrophysics Data System (ADS)

    Hackman, Roger H.; Abatzoglou, Theagenis J.; Arnold, Hal B.; Reagan, John T.

    1993-10-01

    Active acoustic classification of underwater targets is an important problem of current interest. The echo return of such objects has components related to such distinct dynamical elements as the specular (geometric) return, reradiation of elastic resonances, diffracted (or Franz) waves, etc. The arrival times and spectral content of these components will generally give information about the structure and geometry of the scatterer. This information is reflected to the time- frequency structure of the echo return. In this paper, a comparative study is presented of the time-frequency analysis capability of a number of tools in applications to the echo structure of finite elastic cylinders. The time-frequency tools considered include the Wigner-Ville distribution, the Choi-Williams distribution, the Gabor transform, and the continuous wavelet transforms. The comparison is based on echo returns that have been synthesized from numerical T-matrix solutions to the associated free-field scattering problems.

  18. Spectral characteristics of the MST radar returns

    NASA Technical Reports Server (NTRS)

    Rastogi, P. K.

    1983-01-01

    The salient features of the spectra of atmospheric returns due to random refractivity fluctuations in the Mesosphere, Stratosphere, Troposphere MST region are reviewed. The nonhomogeneous layered structure of turbulence is often evident as multiple peaks in the spectra. The time evolution of the spectra observed with a fine Doppler resolution provides evidence for thin regions of turbulence associated with gravity waves and shear instabilities. Embedded in these regions are horizontally extended refractivity structures that produce enhanced returns due to specular reflections. It is conceivable that some enhanced returns arise due to anisotropy of small scale refractivity structures. Observed correlations of the strength of the returns with their Doppler spread, wind shears, and winds provide insights into the physical mechanisms that produce turbulence.

  19. Oxygen production for interplanetary return missions

    NASA Technical Reports Server (NTRS)

    Richter, R.; Ash, R.; Dowler, W.

    1980-01-01

    Interplanetary missions with extraterrestrial returns are limited by large propulsion mass requirements. The injected mass landed on an extraterrestrial body can be reduced substantially by utilizing indigenous materials for the production of propellant on the extraterrestrial body. Analyses reported show that for Mars return missions, in situ production of oxygen during the wait between landing and the next low-energy return opportunity reduces the Earth-launch mass requirements to the allowable limit for direct entry and direct return missions. A small chemical processor using radioisotope thermal energy can extract oxygen several times its own mass from carbon dioxide, during the several-hundred-days wait on Mars. The fundamental element of the concept is the electrolytic process. Solid electrolyte cells for extracting oxygen from gaseous feedstock are identified. The basic physical principles underlying the extraction process are analyzed, and the relations between the major parameters established. The laboratory equipment for experimental investigation of the process is presented.

  20. Insulate Steam Distribution and Condensate Return Lines

    SciTech Connect

    Not Available

    2006-01-01

    This revised ITP tip sheet on insulating steam distribution and condensate return lines provides how-to advice for improving industrial steam systems using low-cost, proven practices and technologies.

  1. STS-26: The return to flight

    NASA Technical Reports Server (NTRS)

    1988-01-01

    The major activities leading up to the return to flight of the Space Shuttles are summarized. Major orbiter modifications and solid rocket motor redesign are described. Shuttle payloads are discussed briefly. Also provided are the biographies of the crew.

  2. Mercury Sample Return using Solar Sails

    NASA Technical Reports Server (NTRS)

    Montgomery, Edward E.; Young, Roy M.; Adams, Charles L.

    2006-01-01

    A conventional Mercury sample return mission requires significant launch mass due to the large deltav required for the outbound and return trips, and the large mass of a planetary lander and ascent vehicle. Solar sailing can be used to reduce lander mass allocation by delivering the lander to a low, thermally safe orbit close to the terminator. Propellant mass is not an issue for solar sails so a sample can be returned relatively easily, without resorting to lengthy, multiple gravity assists. The initial Mercury sample return studies reported here were conducted under ESA contract ESTEC/16534/02/NL/NR, PI Colin McInnes, Technical Officer Peter Falkner. Updated solar sail capabilities were developed under the Ground System Demonstration program, funded by the NASA's In-Space Propulsion Technology (ISPT) Program.

  3. Hayabusa: Navigation Challenges for Earth Return

    NASA Technical Reports Server (NTRS)

    Haw, Robert J.; Bhaskaran, S.; Strauss, W.; Sklyanskiy, E.; Graat, E. J.; Smith, J. J.; Menom, P.; Ardalan, S.; Ballard, C.; Williams, P.; Kawaguchi, J.; Makoto, Y.; Ohnishi, T.

    2011-01-01

    Hayabusa was a JAXA sample-return mission to Itokawa navigated, in part, by JPL personnel. Hayabusa survived several near mission-ending failures at Itokawa yet returned to Earth with an asteroid regolith sample on June 13, 2010. This paper describes NASA/JPL's participation in the Hayabusa mission during the last 100 days of its mission, wherein JPL provided tracking data and orbit determination, plus verification of maneuver design and entry, descent and landing.

  4. 26 CFR 1.6033-4 - Required use of magnetic media for returns by organizations required to file returns under...

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 13 2014-04-01 2014-04-01 false Required use of magnetic media for returns by...) Information Returns § 1.6033-4 Required use of magnetic media for returns by organizations required to file returns under section 6033. The return of an organization that is required to be filed on magnetic...

  5. Comet nucleus and asteroid sample return missions

    NASA Astrophysics Data System (ADS)

    1992-06-01

    Three Advanced Design Projects have been completed this academic year at Penn State. At the beginning of the fall semester the students were organized into eight groups and given their choice of either a comet nucleus or an asteroid sample return mission. Once a mission had been chosen, the students developed conceptual designs. These were evaluated at the end of the fall semester and combined into three separate mission plans, including a comet nucleus same return (CNSR), a single asteroid sample return (SASR), and a multiple asteroid sample return (MASR). To facilitate the work required for each mission, the class was reorganized in the spring semester by combining groups to form three mission teams. An integration team consisting of two members from each group was formed for each mission so that communication and information exchange would be easier among the groups. The types of projects designed by the students evolved from numerous discussions with Penn State faculty and mission planners at the Johnson Space Center Human/Robotic Spacecraft Office. Robotic sample return missions are widely considered valuable precursors to manned missions in that they can provide details about a site's environment and scientific value. For example, a sample return from an asteroid might reveal valuable resources that, once mined, could be utilized for propulsion. These missions are also more adaptable when considering the risk to humans visiting unknown and potentially dangerous locations, such as a comet nucleus.

  6. Mars Earth Return Vehicle (MERV) Propulsion Options

    NASA Technical Reports Server (NTRS)

    Oleson, Steven R.; McGuire, Melissa L.; Burke, Laura; Fincannon, James; Warner, Joe; Williams, Glenn; Parkey, Thomas; Colozza, Tony; Fittje, Jim; Martini, Mike; Packard, Tom; Hemminger, Joseph; Gyekenyesi, John

    2010-01-01

    The COMPASS Team was tasked with the design of a Mars Sample Return Vehicle. The current Mars sample return mission is a joint National Aeronautics and Space Administration (NASA) and European Space Agency (ESA) mission, with ESA contributing the launch vehicle for the Mars Sample Return Vehicle. The COMPASS Team ran a series of design trades for this Mars sample return vehicle. Four design options were investigated: Chemical Return /solar electric propulsion (SEP) stage outbound, all-SEP, all chemical and chemical with aerobraking. The all-SEP and Chemical with aerobraking were deemed the best choices for comparison. SEP can eliminate both the Earth flyby and the aerobraking maneuver (both considered high risk by the Mars Sample Return Project) required by the chemical propulsion option but also require long low thrust spiral times. However this is offset somewhat by the chemical/aerobrake missions use of an Earth flyby and aerobraking which also take many months. Cost and risk analyses are used to further differentiate the all-SEP and Chemical/Aerobrake options.

  7. Comet nucleus and asteroid sample return missions

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Three Advanced Design Projects have been completed this academic year at Penn State. At the beginning of the fall semester the students were organized into eight groups and given their choice of either a comet nucleus or an asteroid sample return mission. Once a mission had been chosen, the students developed conceptual designs. These were evaluated at the end of the fall semester and combined into three separate mission plans, including a comet nucleus same return (CNSR), a single asteroid sample return (SASR), and a multiple asteroid sample return (MASR). To facilitate the work required for each mission, the class was reorganized in the spring semester by combining groups to form three mission teams. An integration team consisting of two members from each group was formed for each mission so that communication and information exchange would be easier among the groups. The types of projects designed by the students evolved from numerous discussions with Penn State faculty and mission planners at the Johnson Space Center Human/Robotic Spacecraft Office. Robotic sample return missions are widely considered valuable precursors to manned missions in that they can provide details about a site's environment and scientific value. For example, a sample return from an asteroid might reveal valuable resources that, once mined, could be utilized for propulsion. These missions are also more adaptable when considering the risk to humans visiting unknown and potentially dangerous locations, such as a comet nucleus.

  8. Weather effects on the returns and volatility of the Shanghai stock market

    NASA Astrophysics Data System (ADS)

    Kang, Sang Hoon; Jiang, Zhuhua; Lee, Yeonjeong; Yoon, Seong-Min

    2010-01-01

    This study investigates the weather effects on returns as well as volatility in the Shanghai stock market. In order to analyze the influence of the opening of B-share market to domestic investors, it is assumed that domestic investors are more sensitive to the Shanghai local weather than foreign investors. In doing so, extreme weather condition dummies are generated by using the 21-day and 31-day moving average and its standard deviation. Empirical analysis provides two key results regarding weather effects. First, the weather effect exists in the A-share returns, but does not exist in the B-share returns over the whole period. In addition, the post-opening period shows the strong weather effect on B-share returns only, indicating that the market openness to domestic investors results in the weather effect. Second, the weather effect has a strong influence on the volatility of both A- and B-share returns. Similar to the case of returns, the weather effect on volatility is explained by the openness of B-share market.

  9. Analyzing traffic source impact on returning visitors ratio in information provider website

    NASA Astrophysics Data System (ADS)

    Prasetio, A.; Sari, P. K.; Sharif, O. O.; Sofyan, E.

    2016-04-01

    Web site performance, especially returning visitor is an important metric for an information provider web site. Since high returning visitor is a good indication of a web site’s visitor loyalty, it is important to find a way to improve this metric. This research investigated if there is any difference on returning visitor metric among three web traffic sources namely direct, referral and search. Monthly returning visitor and total visitor from each source is retrieved from Google Analytics tools and then calculated to measure returning visitor ratio. The period of data observation is from July 2012 to June 2015 resulting in a total of 108 samples. These data then analysed using One-Way Analysis of Variance (ANOVA) to address our research question. The results showed that different traffic source has significantly different returning visitor ratio especially between referral traffic source and the other two traffic sources. On the other hand, this research did not find any significant difference between returning visitor ratio from direct and search traffic sources. The owner of the web site can focus to multiply referral links from other relevant sites.

  10. 49 CFR 236.720 - Circuit, common return.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Circuit, common return. A term applied where one wire is used for the return of more than one electric circuit. ... 49 Transportation 4 2012-10-01 2012-10-01 false Circuit, common return. 236.720 Section...

  11. 49 CFR 236.720 - Circuit, common return.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Circuit, common return. A term applied where one wire is used for the return of more than one electric circuit. ... 49 Transportation 4 2013-10-01 2013-10-01 false Circuit, common return. 236.720 Section...

  12. 49 CFR 236.720 - Circuit, common return.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Circuit, common return. A term applied where one wire is used for the return of more than one electric circuit. ... 49 Transportation 4 2010-10-01 2010-10-01 false Circuit, common return. 236.720 Section...

  13. 49 CFR 236.720 - Circuit, common return.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Circuit, common return. A term applied where one wire is used for the return of more than one electric circuit. ... 49 Transportation 4 2014-10-01 2014-10-01 false Circuit, common return. 236.720 Section...

  14. 49 CFR 236.720 - Circuit, common return.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Circuit, common return. A term applied where one wire is used for the return of more than one electric circuit. ... 49 Transportation 4 2011-10-01 2011-10-01 false Circuit, common return. 236.720 Section...

  15. Mars sample return power supply

    NASA Technical Reports Server (NTRS)

    Hoang, Don; Ludwigs, Sharon; Schmitz, Paul; Wright, John

    1988-01-01

    A power supply is designed for a vehicle able to operate on the surface of Mars for a period of 5 to 10 years. This vehicle will be used for sample and data collection. The design is based on the assumption that the vehicle will be unmanned. Also, there will be no means by which components could be repaired or replaced while on the Martian surface. A consequence of this is that all equipment must meet high standards of reliability and, if possible, redundancy. Power will be supplied to the vehicle by means of a General Purpose Heat Source capable of producing a minimum of 7 kW of thermal power. The heat generated from the General Purpose Heat Source will be transferred to a Stirling engine via hot side heat pipes. The Stirling engine will then convert this heat into 2 kW of electrical power. Cold side heat pipes will be used to carry away waste heat, which will be released to the Martian environment via radiators connected to the end of the cold side heat pipes.

  16. Comet Odyssey: Comet Surface Sample Return

    NASA Astrophysics Data System (ADS)

    Weissman, Paul R.; Bradley, J.; Smythe, W. D.; Brophy, J. R.; Lisano, M. E.; Syvertson, M. L.; Cangahuala, L. A.; Liu, J.; Carlisle, G. L.

    2010-10-01

    Comet Odyssey is a proposed New Frontiers mission that would return the first samples from the surface of a cometary nucleus. Stardust demonstrated the tremendous power of analysis of returned samples in terrestrial laboratories versus what can be accomplished in situ with robotic missions. But Stardust collected only 1 milligram of coma dust, and the 6.1 km/s flyby speed heated samples up to 2000 K. Comet Odyssey would collect two independent 800 cc samples directly from the surface in a far more benign manner, preserving the primitive composition. Given a minimum surface density of 0.2 g/cm3, this would return two 160 g surface samples to Earth. Comet Odyssey employs solar-electric propulsion to rendezvous with the target comet. After 180 days of reconnaissance and site selection, the spacecraft performs a "touch-and-go” maneuver with surface contact lasting 3 seconds. A brush-wheel sampler on a remote arm collects up to 800 cc of sample. A duplicate second arm and sampler collects the second sample. The samples are placed in a return capsule and maintained at colder than -70 C during the return flight and at colder than -30 C during re-entry and for up to six hours after landing. The entire capsule is then refrigerated and transported to the Astromaterials Curatorial Facility at NASA/JSC for initial inspection and sample analysis by the Comet Odyssey team. Comet Odyssey's planned target was comet 9P/Tempel 1, with launch in December 2017 and comet arrival in June 2022. After a stay of 300 days at the comet, the spacecraft departs and arrives at Earth in May 2027. Comet Odyssey is a forerunner to a flagship Cryogenic Comet Sample Return mission that would return samples from deep below the nucleus surface, including volatile ices. This work was supported by internal funds from the Jet Propulsion Laboratory.

  17. Optimization of return electrodes in neurostimulating arrays

    NASA Astrophysics Data System (ADS)

    Flores, Thomas; Goetz, Georges; Lei, Xin; Palanker, Daniel

    2016-06-01

    Objective. High resolution visual prostheses require dense stimulating arrays with localized inputs of individual electrodes. We study the electric field produced by multielectrode arrays in electrolyte to determine an optimal configuration of return electrodes and activation sequence. Approach. To determine the boundary conditions for computation of the electric field in electrolyte, we assessed current dynamics using an equivalent circuit of a multielectrode array with interleaved return electrodes. The electric field modeled with two different boundary conditions derived from the equivalent circuit was then compared to measurements of electric potential in electrolyte. To assess the effect of return electrode configuration on retinal stimulation, we transformed the computed electric fields into retinal response using a model of neural network-mediated stimulation. Main results. Electric currents at the capacitive electrode-electrolyte interface redistribute over time, so that boundary conditions transition from equipotential surfaces at the beginning of the pulse to uniform current density in steady state. Experimental measurements confirmed that, in steady state, the boundary condition corresponds to a uniform current density on electrode surfaces. Arrays with local return electrodes exhibit improved field confinement and can elicit stronger network-mediated retinal response compared to those with a common remote return. Connecting local return electrodes enhances the field penetration depth and allows reducing the return electrode area. Sequential activation of the pixels in large monopolar arrays reduces electrical cross-talk and improves the contrast in pattern stimulation. Significance. Accurate modeling of multielectrode arrays helps optimize the electrode configuration to maximize the spatial resolution, contrast and dynamic range of retinal prostheses.

  18. The OSIRIS-Rex Asteroid Sample Return: Mission Operations Design

    NASA Technical Reports Server (NTRS)

    Gal-Edd, Jonathan; Cheuvront, Allan

    2014-01-01

    The OSIRIS-REx mission employs a methodical, phased approach to ensure success in meeting the missions science requirements. OSIRIS-REx launches in September 2016, with a backup launch period occurring one year later. Sampling occurs in 2019. The departure burn from Bennu occurs in March 2021. On September 24, 2023, the SRC lands at the Utah Test and Training Range (UTTR). Stardust heritage procedures are followed to transport the SRC to Johnson Space Center, where the samples are removed and delivered to the OSIRIS-REx curation facility. After a six-month preliminary examination period the mission will produce a catalog of the returned sample, allowing the worldwide community to request samples for detailed analysis.Traveling and returning a sample from an Asteroid that has not been explored before requires unique operations consideration. The Design Reference Mission (DRM) ties together space craft, instrument and operations scenarios. The project implemented lessons learned from other small body missions: APLNEAR, JPLDAWN and ESARosetta. The key lesson learned was expected the unexpected and implement planning tools early in the lifecycle. In preparation to PDR, the project changed the asteroid arrival date, to arrive one year earlier and provided additional time margin. STK is used for Mission Design and STKScheduler for instrument coverage analysis.

  19. 26 CFR 301.6103(n)-1 - Disclosure of returns and return information in connection with written contracts or agreements...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... employees of a contractor for purposes of programming, maintaining, repairing, or testing computer equipment... reproduction of returns or return information, the programming, maintenance, repair, or testing of equipment...

  20. Impact of global financial crisis on precious metals returns: An application of ARCH and GARCH methods

    NASA Astrophysics Data System (ADS)

    Ismail, Mohd Tahir; Abdullah, Nurul Ain; Abdul Karim, Samsul Ariffin

    2013-04-01

    This paper is focusing on seeing the resilient of precious metals returns in facing the global financial crisis and provides a new guide for the investors before making investment decisions on precious metals. Four types of precious metals returns which are the variables selected in this study. The precious metals are gold, silver, bronze and platinum. All the variables are transferred to natural logarithm (ln). Daily data over the period 2 January 1995 to 30 December 2011 is used. Unit root tests that involve Augmented Dickey-Fuller (ADF) and Kwiatkowski-Phillips-Schmidt-Shin (KPSS) tests have been employed in determining the stationarity of the variables. Autoregressive Conditional Heteroscedasticity (ARCH) and Generalized Autoregressive Conditional Heteroscedasticity (GARCH) methods have been applied in measuring the impact of global financial crisis on precious metals returns. The result shows that investing in platinum is less risky compared to the other precious metals because it is not influence by the crisis period.

  1. Evolution of periodicity in periodical cicadas

    PubMed Central

    Ito, Hiromu; Kakishima, Satoshi; Uehara, Takashi; Morita, Satoru; Koyama, Takuya; Sota, Teiji; Cooley, John R.; Yoshimura, Jin

    2015-01-01

    Periodical cicadas (Magicicada spp.) in the USA are famous for their unique prime-numbered life cycles of 13 and 17 years and their nearly perfectly synchronized mass emergences. Because almost all known species of cicada are non-periodical, periodicity is assumed to be a derived state. A leading hypothesis for the evolution of periodicity in Magicicada implicates the decline in average temperature during glacial periods. During the evolution of periodicity, the determinant of maturation in ancestral cicadas is hypothesized to have switched from size dependence to time (period) dependence. The selection for the prime-numbered cycles should have taken place only after the fixation of periodicity. Here, we build an individual-based model of cicadas under conditions of climatic cooling to explore the fixation of periodicity. In our model, under cold environments, extremely long juvenile stages lead to extremely low adult densities, limiting mating opportunities and favouring the evolution of synchronized emergence. Our results indicate that these changes, which were triggered by glacial cooling, could have led to the fixation of periodicity in the non-periodical ancestors. PMID:26365061

  2. Where Are "Women Returners" Returning From? Deconstructing Domestication in the Context of Lifelong Learning.

    ERIC Educational Resources Information Center

    Clarke, Julia

    The question of where "women returners" to education are returning from was examined through an exploration of the life histories of 18 women in southern England. The study focused on the biographies of women who regarded themselves as primarily responsible for the care of others and yet whose aspirations involved some form of continuing…

  3. 78 FR 26506 - Disclosure of Returns and Return Information to Designee of Taxpayer

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-07

    ... Internal Revenue Service 26 CFR Part 301 RIN 1545-BJ19 Disclosure of Returns and Return Information to Designee of Taxpayer AGENCY: Internal Revenue Service (IRS), Treasury. ACTION: Final regulations. SUMMARY... proposed rulemaking (REG-153338-09) in the Federal Register, 76 FR 14827, on March 18, 2011, which...

  4. 76 FR 31543 - Disclosure of Returns and Return Information to Designee of Taxpayer; Hearing Cancellation

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-01

    ... Internal Revenue Service 26 CFR Part 301 RIN 1545-BJ19 Disclosure of Returns and Return Information to Designee of Taxpayer; Hearing Cancellation AGENCY: Internal Revenue Service (IRS), Treasury. ACTION... (76 FR 14827) announced that a public hearing was scheduled for June 9, 2011, at 10 a.m. in the...

  5. 27 CFR 479.151 - Failure to make returns: Substitute returns.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 3 2011-04-01 2010-04-01 true Failure to make returns: Substitute returns. 479.151 Section 479.151 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE FIREARMS AND AMMUNITION MACHINE GUNS,...

  6. 27 CFR 479.151 - Failure to make returns: Substitute returns.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 3 2010-04-01 2010-04-01 false Failure to make returns: Substitute returns. 479.151 Section 479.151 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE FIREARMS AND AMMUNITION MACHINE GUNS,...

  7. 27 CFR 479.151 - Failure to make returns: Substitute returns.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 3 2014-04-01 2014-04-01 false Failure to make returns: Substitute returns. 479.151 Section 479.151 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE FIREARMS AND AMMUNITION MACHINE GUNS,...

  8. 27 CFR 479.151 - Failure to make returns: Substitute returns.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 3 2013-04-01 2013-04-01 false Failure to make returns: Substitute returns. 479.151 Section 479.151 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE FIREARMS AND AMMUNITION MACHINE GUNS,...

  9. 27 CFR 479.151 - Failure to make returns: Substitute returns.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 3 2012-04-01 2010-04-01 true Failure to make returns: Substitute returns. 479.151 Section 479.151 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE FIREARMS AND AMMUNITION MACHINE GUNS,...

  10. Return Migration: A Study of College Graduates Returning to Rural U.S. Homes

    ERIC Educational Resources Information Center

    Mahoney, Elizabeth D.

    2009-01-01

    The purpose of this study is to explore perceptions of return migration experiences and gain knowledge from rural residents who have left to obtain a college education and start careers in non-rural areas, and who then returned to their rural hometowns with the social and economic benefits of a college education, and other valuable resources. This…

  11. Return to Play After Cervical Disc Surgery.

    PubMed

    Kang, Daniel G; Anderson, Justin C; Lehman, Ronald A

    2016-10-01

    Criteria for return to sports and athletic activities after cervical spine surgery are unclear. There is limited literature regarding the outcomes and optimal criteria. Determining return to play criteria remains a challenge and continues to depend on the experience and good judgment of the treating surgeon. There is strong consensus in the literature, despite lack of evidence-based data, that athletes after single-level anterior cervical discectomy and fusion (ACDF) may safely return to collision and high-velocity sports. The athlete should be counseled and managed on a case-by-case basis, taking into consideration the type of sport, player-specific variables, and type of surgery performed. PMID:27543397

  12. SOCCER: Comet Coma Sample Return Mission

    NASA Technical Reports Server (NTRS)

    Albee, A. L.; Uesugi, K. T.; Tsou, Peter

    1994-01-01

    Comets, being considered the most primitive bodies in the solar system, command the highest priority among solar system objects for studying solar nebula evolution and the evolution of life through biogenic elements and compounds. Sample Of Comet Coma Earth Return (SOCCER), a joint effort between NASA and the Institute of Space and Astronautical Science (ISAS) in Japan, has two primary science objectives: (1) the imaging of the comet nucleus and (2) the return to Earth of samples of volatile species and intact dust. This effort makes use of the unique strengths and capabilities of both countries in realizing this important quest for the return of samples from a comet. This paper presents an overview of SOCCER's science payloads, engineering flight system, and its mission operations.

  13. Planetary Protection Technology for Mars Sample Return

    NASA Technical Reports Server (NTRS)

    Gershman, Robert

    2005-01-01

    The NASA Mars Exploration Program has recently adopted a plan that includes a first Mars sample return (MSR) mission proposed for launch in 2013. Such a mission would deal with two new categories of planetary protection requirements: (1) assuring a very low probability of inadvertent release of the sample in order to provide extra protection against the extremely unlikely possibility of biological hazards in the returned material and (2) keeping the samples free of round-trip Earth organisms to facilitate confirmation of safety after return to Earth. This paper describes the planetary-protection-related technical challenges awaiting any MSR mission and describes work in progress on technology needed to meet these challenges. New technology is needed for several functions. Containment assurance requires breaking the chain of contact with Mars: the exterior of the sample container must not be contaminated with Mars material either during the loading process or during launch from the Mars surface.

  14. The Hayabusa Spacecraft Sample Return Mission

    NASA Technical Reports Server (NTRS)

    Abell, Paul A.

    2010-01-01

    The Hayabusa (originally known as MUSES-C) engineering spacecraft was launched by the 5th Mu V launch vehicle on May 9, 2003 by the Japan Aerospace Exploration Agency (JAXA). It was designed to acquire samples from the surface of near-Earth asteroid 25143 Itokawa (1998 SF36) and return them to Earth. The main objectives of the mission were to demonstrate the performance of various technologies such as ion engine performance, autonomous navigation and control, asteroid surface sampling, and recovery of the return capsule after high speed re-entry. Hayabusa successfully returned a small capsule to Earth in June 2010 with a parachute assisted landing in Woomera, Australia. Details of the Hayabusa mission and the recovery operation will be presented for discussion.

  15. Earth Entry Vehicle for Mars Sample Return

    NASA Technical Reports Server (NTRS)

    Mitcheltree, R. A.; Braun, R. D.; Hughes. S. J.; Simonsen, L. C.

    2000-01-01

    The driving requirement for design of a Mars Sample return mission is assuring containment of the returned samples. The impact of this requirement on developmental costs, mass allocation, and design approach of the Earth Entry Vehicle is significant. A simple Earth entry vehicle is described which can meet these requirements and safely transport the Mars Sample Return mission's sample through the Earth's atmosphere to a recoverable location on the surface. Detailed analysis and test are combined with probabilistic risk assessment to design this entirely passive concept that circumvents the potential failure modes of a parachute terminal descent system. The design also possesses features that mitigate other risks during the entry, descent, landing and recovery phases. The results of a full-scale drop test are summarized.

  16. Stakeholder views on returning research results.

    PubMed

    Haga, Susanne B; Zhao, Jennifer Q

    2013-01-01

    While the disclosure of research findings is relevant to all types of biomedical research, it has garnered particular attention with respect to genetics and genomics research due to some of the unique aspects of the data and the high public profile of the field. In this chapter, we review the attitudes of stakeholders (research participants, policymakers, and researchers) to define areas of consensus regarding the issue of returning research results across and within groups. In addition to stakeholder attitudes about obligations and interest in research results, other major related issues related to returning research results, such as informed consent, communication of research results, and cost, are discussed. Given the consensus between stakeholders to return summary reports of a study's outcomes and individual research results of clinical significance, we conclude that the time has come to encourage, if not require, researchers to consider these issues in the developmental planning stages of a project and to plan and budget accordingly. PMID:24262096

  17. Planetary protection issues for sample return missions.

    PubMed

    DeVincenzi, D L; Klein, H P

    1989-01-01

    Sample return missions from a comet nucleus and the Mars surface are currently under study in the US, USSR, and by ESA. Guidance on Planetary Protection (PP) issues is needed by mission scientists and engineers for incorporation into various elements of mission design studies. Although COSPAR has promulgated international policy on PP for various classes of solar system exploration missions, the applicability of this policy to sample return missions, in particular, remains vague. In this paper, we propose a set of implementing procedures to maintain the scientific integrity of these samples. We also propose that these same procedures will automatically assure that COSPAR-derived PP guidelines are achieved. The recommendations discussed here are the first step toward development of official COSPAR implementation requirements for sample return missions. PMID:11537373

  18. Medical returns as class transformation: situating migrants' medical returns within a framework of transnationalism.

    PubMed

    Horton, Sarah B

    2013-01-01

    Because studies of migrants' 'medical returns' have been largely confined to the field of public health, such forms of return migration are rarely contextualized within the rich social scientific literature on transnational migration. Drawing on ethnographic interviews with Mexican migrants in an immigrant enclave in central California, I show that migrants' reasons for returning to their hometowns for care must be understood within the class disjunctures facilitated by migration. While migrants' Medicaid insurance confined them to public clinics and hospitals in the United States, their migrant dollars enabled them to visit private doctors and clinics in Mexico. Yet medical returns were not mere medical arbitrage, but also allowed migrants to access care that had previously been foreclosed to them as poor peasants in Mexico. Thus crossing the border enabled a dual class transformation, as Mexican migrants transitioned from Medicaid recipients to cash-paying patients, and from poor rural peasants to 'returning royalty.' PMID:23944244

  19. Horizontal fields generated by return strokes

    NASA Technical Reports Server (NTRS)

    Cooray, Vernon

    1991-01-01

    Horizontal fields generated by return strokes play an important role in the interaction of lightning generated electric fields with power lines. In many of the recent investigations on the interaction of lightning electromagnetic fields with power lines, the horizontal field was calculated by employing the expression for the tilt of the electric field of a plane wave propagating over finitely conducting earth. The method is suitable for calculating horizontal fields generated by return strokes at distances as close as 200m. At these close ranges, the use of the wavetilt expression can cause large errors.

  20. Chloroquine-resistant malaria in travelers returning from Haiti after 2010 earthquake.

    PubMed

    Gharbi, Myriam; Pillai, Dylan R; Lau, Rachel; Hubert, Véronique; Khairnar, Krishna; Existe, Alexandre; Kendjo, Eric; Dahlström, Sabina; Guérin, Philippe J; Le Bras, Jacques

    2012-08-01

    We investigated chloroquine sensitivity to Plasmodium falciparum in travelers returning to France and Canada from Haiti during a 23-year period. Two of 19 isolates obtained after the 2010 earthquake showed mixed pfcrt 76K+T genotype and high 50% inhibitory concentration. Physicians treating malaria acquired in Haiti should be aware of possible chloroquine resistance. PMID:22840888

  1. Chloroquine-Resistant Malaria in Travelers Returning from Haiti after 2010 Earthquake

    PubMed Central

    Pillai, Dylan R.; Lau, Rachel; Hubert, Véronique; Khairnar, Krishna; Existe, Alexandre; Kendjo, Eric; Dahlström, Sabina; Guérin, Philippe J.; Le Bras, Jacques

    2012-01-01

    We investigated chloroquine sensitivity to Plasmodium falciparum in travelers returning to France and Canada from Haiti during a 23-year period. Two of 19 isolates obtained after the 2010 earthquake showed mixed pfcrt 76K+T genotype and high 50% inhibitory concentration. Physicians treating malaria acquired in Haiti should be aware of possible chloroquine resistance. PMID:22840888

  2. The Relationship between Return on Profitability and Costs of Outsourcing Information Technology Technical Support

    ERIC Educational Resources Information Center

    Odion, Segun

    2011-01-01

    The purpose of this quantitative correlational research study was to examine the relationship between costs of operation and total return on profitability of outsourcing information technology technical support in a two-year period of outsourcing operations. United States of America list of Fortune 1000 companies' chief information officers…

  3. Dynamics of Rate of Returns for Postgraduate Education in Taiwan: The Impact of Higher Education Expansion

    ERIC Educational Resources Information Center

    Yang, Chih-Hai; Lin, Chun-Hung A.; Lin, Chien-Ru

    2011-01-01

    This paper analyzes the dynamics of rate of returns for postgraduate education and the determinants of wage premiums for postgraduate labor, especially for the impact of higher education expansions, in terms of quantity and quality, since the late 1990s in Taiwan. Utilizing quasi-panel data over the 1990-2004 period and employing the double fixed…

  4. Telecommunications Policy Research Conference. Alternatives to Rate of Return Regulation Section. Papers.

    ERIC Educational Resources Information Center

    Telecommunications Policy Research Conference, Inc., Washington, DC.

    The first of two papers presented in this section, "Price-Caps: Theory and Implementation" (Peter B. Linhart and Roy Radner) describes a proposed method of regulation involving price caps on core services and no price regulation of other services. This method is designed to replace rate-of-return regulation during a transition period to a…

  5. 75 FR 14539 - Furnishing Identifying Number of Tax Return Preparer

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-26

    ...This document contains proposed regulations under section 6109 of the Internal Revenue Code (Code) that provide guidance to tax return preparers on furnishing an identifying number on tax returns and claims for refund of tax that they prepare. These proposed regulations provide guidance on the identifying number of a tax return preparer for tax returns and claims for refund filed before and......

  6. 26 CFR 31.6011(a)-6 - Final returns.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... person filing a final return (other than a final return on Form 942 or Form 943) must furnish information... return, and such person shall furnish information showing the date of the last payment of taxable... make a return on a particular form pursuant to § 31.6011(a)-1, § 31.6011(a)-4, or § 31.6011(a)-5,...

  7. 26 CFR 31.6011(a)-6 - Final returns.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... person filing a final return (other than a final return on Form 942 or Form 943) must furnish information... return, and such person shall furnish information showing the date of the last payment of taxable... make a return on a particular form pursuant to § 31.6011(a)-1, § 31.6011(a)-4, or § 31.6011(a)-5,...

  8. 26 CFR 31.6011(a)-6 - Final returns.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... person filing a final return (other than a final return on Form 942 or Form 943) must furnish information... return, and such person shall furnish information showing the date of the last payment of taxable... make a return on a particular form pursuant to § 31.6011(a)-1, § 31.6011(a)-4, or § 31.6011(a)-5,...

  9. 26 CFR 31.6011(a)-6 - Final returns.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... person filing a final return (other than a final return on Form 942 or Form 943) must furnish information... return, and such person shall furnish information showing the date of the last payment of taxable... make a return on a particular form pursuant to § 31.6011(a)-1, § 31.6011(a)-4, or § 31.6011(a)-5,...

  10. 26 CFR 1.6013-1 - Joint returns.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 13 2011-04-01 2011-04-01 false Joint returns. 1.6013-1 Section 1.6013-1...) INCOME TAXES (CONTINUED) Tax Returns Or Statements § 1.6013-1 Joint returns. (a) In general. (1) A husband and wife may elect to make a joint return under section 6013(a) even though one of the spouses...

  11. 26 CFR 1.6013-1 - Joint returns.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 13 2014-04-01 2014-04-01 false Joint returns. 1.6013-1 Section 1.6013-1...) INCOME TAXES (CONTINUED) Tax Returns Or Statements § 1.6013-1 Joint returns. (a) In general. (1) A husband and wife may elect to make a joint return under section 6013(a) even though one of the spouses...

  12. 26 CFR 1.6013-1 - Joint returns.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 26 Internal Revenue 13 2013-04-01 2013-04-01 false Joint returns. 1.6013-1 Section 1.6013-1...) INCOME TAXES (CONTINUED) Tax Returns Or Statements § 1.6013-1 Joint returns. (a) In general. (1) A husband and wife may elect to make a joint return under section 6013(a) even though one of the spouses...

  13. 26 CFR 1.6013-1 - Joint returns.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 13 2012-04-01 2012-04-01 false Joint returns. 1.6013-1 Section 1.6013-1...) INCOME TAXES (CONTINUED) Tax Returns Or Statements § 1.6013-1 Joint returns. (a) In general. (1) A husband and wife may elect to make a joint return under section 6013(a) even though one of the spouses...

  14. 26 CFR 1.6013-1 - Joint returns.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 13 2010-04-01 2010-04-01 false Joint returns. 1.6013-1 Section 1.6013-1...) INCOME TAXES Tax Returns Or Statements § 1.6013-1 Joint returns. (a) In general. (1) A husband and wife may elect to make a joint return under section 6013(a) even though one of the spouses has no...

  15. 26 CFR 301.6501(e)-1 - Omission from return.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... taxes. (i) If a private foundation omits from its annual return with respect to the tax imposed by... after the return was filed. If a private foundation discloses in its return (or in a schedule or... foundation has omitted more than 25 percent of the tax reported on its return. (ii) If a private...

  16. 26 CFR 301.6501(e)-1 - Omission from return.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... taxes. (i) If a private foundation omits from its annual return with respect to the tax imposed by... after the return was filed. If a private foundation discloses in its return (or in a schedule or... foundation has omitted more than 25 percent of the tax reported on its return. (ii) If a private...

  17. 26 CFR 301.6501(e)-1 - Omission from return.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... taxes. (i) If a private foundation omits from its annual return with respect to the tax imposed by... after the return was filed. If a private foundation discloses in its return (or in a schedule or... foundation has omitted more than 25 percent of the tax reported on its return. (ii) If a private...

  18. 26 CFR 301.6501(e)-1 - Omission from return.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... taxes. (i) If a private foundation omits from its annual return with respect to the tax imposed by... after the return was filed. If a private foundation discloses in its return (or in a schedule or... foundation has omitted more than 25 percent of the tax reported on its return. (ii) If a private...

  19. 7 CFR 3560.305 - Return on investment.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 15 2012-01-01 2012-01-01 false Return on investment. 3560.305 Section 3560.305... AGRICULTURE DIRECT MULTI-FAMILY HOUSING LOANS AND GRANTS Financial Management § 3560.305 Return on investment. (a) Borrower's return on investment. Borrowers may receive a return on their investment (ROI)...

  20. 7 CFR 3560.305 - Return on investment.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Return on investment. 3560.305 Section 3560.305... AGRICULTURE DIRECT MULTI-FAMILY HOUSING LOANS AND GRANTS Financial Management § 3560.305 Return on investment. (a) Borrower's return on investment. Borrowers may receive a return on their investment (ROI)...

  1. 7 CFR 3560.305 - Return on investment.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 15 2013-01-01 2013-01-01 false Return on investment. 3560.305 Section 3560.305... AGRICULTURE DIRECT MULTI-FAMILY HOUSING LOANS AND GRANTS Financial Management § 3560.305 Return on investment. (a) Borrower's return on investment. Borrowers may receive a return on their investment (ROI)...

  2. The Tail Exponent for Stock Returns in Bursa Malaysia for 2003-2008

    NASA Astrophysics Data System (ADS)

    Rusli, N. H.; Gopir, G.; Usang, M. D.

    2010-07-01

    A developed discipline of econophysics that has been introduced is exhibiting the application of mathematical tools that are usually applied to the physical models for the study of financial models. In this study, an analysis of the time series behavior of several blue chip and penny stock companies in Main Market of Bursa Malaysia has been performed. Generally, the basic quantity being used is the relative price changes or is called the stock price returns, contains daily-sampled data from the beginning of 2003 until the end of 2008, containing 1555 trading days recorded. The aim of this paper is to investigate the tail exponent in tails of the distribution for blue chip stocks and penny stocks financial returns in six years period. By using a standard regression method, it is found that the distribution performed double scaling on the log-log plot of the cumulative probability of the normalized returns. Thus we calculate α for a small scale return as well as large scale return. Based on the result obtained, it is found that the power-law behavior for the probability density functions of the stock price absolute returns P(z)˜z-α with values lying inside and outside the Lévy stable regime with values α>2. All the results were discussed in detail.

  3. Planetary Protection for LIFE-Sample Return from Enceladus

    NASA Astrophysics Data System (ADS)

    Tsou, Peter; Yano, Hajime; Takano, Yoshinori; McKay, David; Takai, Ken; Anbar, Ariel; Baross, J.

    Introduction: We are seeking a balanced approach to returning Enceladus plume samples to state-of-the-art terrestrial laboratories to search for signs of life. NASA, ESA, JAXA and other space agencies are seeking habitable worlds and life beyond Earth. Enceladus, an icy moon of Saturn, is the first known body in the Solar System besides Earth to emit liquid water from its interior. Enceladus is the most accessible body in our Solar System for a low cost flyby sample return mission to capture aqueous based samples, to determine its state of life development, and shed light on how life can originate on wet planets/moons. LIFE combines the unique capabilities of teams of international exploration expertise. These returned Enceladus plume samples will determine if this habitable body is in fact inhabited [McKay et al, 2014]. This paper describes an approach for the LIFE mission to capture and return samples from Enceladus while meeting NASA and COSPAR planetary protection requirements. Forward planetary protection requirements for spacecraft missions to icy solar system bodies have been defined, however planetary protection requirements specific to an Earth return of samples collected from Enceladus or other Outer Planet Icy Moons, have yet to be defined. Background: From the first half century of space exploration, we have returned samples only from the Moon, comet Wild 2, the Solar Wind and the asteroid Itokawa. The in-depth analyses of these samples in terrestrial laboratories have yielded detailed chemical information that could not have been obtained otherwise. While obtaining samples from Solar System bodies is trans-formative science, it is rarely performed due to cost and complexity. The discovery by Cassini of geysers on Enceladus and organic materials in the ejected plume indicates that there is an exceptional opportunity and strong scientific rationale for LIFE. The earliest low-cost possible flight opportunity is the next Discovery Mission [Tsou et al 2012

  4. Reality Check: A Teacher Educator Returns Home

    ERIC Educational Resources Information Center

    Scherff, Lisa; Kaplan, Jeff

    2006-01-01

    This collaborative self-study, told through email excerpts and reflections, explores a teacher educator's return to high school teaching. In this study, we juxtapose our voices and alternate between past and present to develop insights that reveal how going back can lead to moving forward with respect to educating prospective teachers. While the…

  5. There's Little Return for Attentional Momentum

    ERIC Educational Resources Information Center

    Snyder, Janice J.; Schmidt, William C.; Kingstone, Alan

    2009-01-01

    Inhibition of return (IOR) refers to a delay in response time (RT) to targets appearing at a previously cued location. The prevailing view is that IOR reflects visual-motor inhibition. The "attentional momentum" account rejects this idea, and instead proposes that IOR reflects an automatic shift of attention away from the cued location resulting…

  6. Mars Sample Return from Meridiani Planum

    NASA Technical Reports Server (NTRS)

    Mittlefehldt, David W.

    2008-01-01

    The NASA Mars Exploration Program has four main goals: (i) determine if life ever arose there, (ii) understand the processes and history of its climate, (iii) determine the evolution of its surface and interior, and (iv) prepare for human exploration of Mars. These goals are embodied in the NASA Mars exploration strategy Follow the Water. Current Mars exploration tactics for lander missions build on knowledge gained by prior orbital investigations; the science rationale for choosing landing sites is based on the current best interpretation of the geology. A future Mars sample return mission will greatly exceed in cost typical lander missions because of the need to design for return to Earth and the infrastructure needed on Earth to curate and process the samples safely and cleanly. Because of this added cost burden, expectations for science return are higher. There must be some prospect that the returned samples will allow for testing higher level hypotheses relevant to NASA's goals. Site selection must be based on knowledge gained from prior in situ measurements to enhance the prospects for successfully meeting these goals. I will argue that Meridiani Planum should be that site.

  7. A Sample Return Container with Hermetic Seal

    NASA Technical Reports Server (NTRS)

    Kong, Kin Yuen; Rafeek, Shaheed; Sadick, Shazad; Porter, Christopher C.

    2000-01-01

    A sample return container is being developed by Honeybee Robotics to receive samples from a derivative of the Champollion/ST4 Sample Acquisition and Transfer Mechanism or other samplers and then hermetically seal samples for a sample return mission. The container is enclosed in a phase change material (PCM) chamber to prevent phase change during return and re-entry to earth. This container is designed to operate passively with no motors and actuators. Using the sampler's featured drill tip for interfacing, transfer-ring and sealing samples, the container consumes no electrical power and therefore minimizes sample temperature change. The circular container houses a few isolated canisters, which will be sealed individually for samples acquired from different sites or depths. The drill based sampler indexes each canister to the sample transfer position, below the index interface for sample transfer. After sample transfer is completed, the sampler indexes a seal carrier, which lines up seals with the openings of the canisters. The sampler moves to the sealing interface and seals the sample canisters one by one. The sealing interface can be designed to work with C-seals, knife edge seals and cup seals. Again, the sampler provides all sealing actuation. This sample return container and co-engineered sample acquisition system are being developed by Honeybee Robotics in collaboration with the JPL Exploration Technology program.

  8. Near-Earth Asteroid Sample Return Missions

    NASA Technical Reports Server (NTRS)

    Sears, D. W. G.; Allen, C. C.; Britt, D. T.; Brownlee, D. E.; Cheng, A.; Chapman, C. R.; Clark, B. C.; Drake, B. G.; Franchi, I. A.; Gorevan, S.

    2001-01-01

    The rate of discovery of new Near Earth Asteroids (NEAs) and the success of D-S 1 and NEAR-Shoemaker, suggest that sample return from NEAs is now technically feasible. Here we present a summary of a recent workshop on the topic. Additional information is contained in the original extended abstract.

  9. Returns to Education in Rural China

    ERIC Educational Resources Information Center

    Zhao, Litao

    2007-01-01

    Based on one of the most widely used datasets by foreign-based sociologists, this paper examines the rate of returns to education in rural China. Compared with the previous studies that showed rather low rates in rural areas throughout the 1980s, this study finds a considerably higher rate in 1996. A chief contributor is the rapid non-agricultural…

  10. Renewal, reform, and return to flight.

    PubMed

    Dorr, Robert F

    2005-06-01

    The Washington Watch column discusses budget issues on Capitol Hill relating to aerospace issues, including the shuttle's delayed return to flight and Michael Griffin becoming the new NASA administrator; the Transportation Security Administration becoming downsized; and new personnel at the Pentagon. PMID:16007744

  11. Enterprise Return on a Training Investment.

    ERIC Educational Resources Information Center

    Doucouliagos, Chris; Sgro, Pasquale

    The return on investment (ROI) obtained by enterprises that invest in training was examined through case studies of seven Australian work organizations. The case study organizations included a government-owned transportation company, a privately owned company, a major nongovernmental charitable organization, a publicly listed corporation, and two…

  12. The Mechanism Underlying Inhibition of Saccadic Return

    ERIC Educational Resources Information Center

    Ludwig, Casimir J. H.; Farrell, Simon; Ellis, Lucy A.; Gilchrist, Iain D.

    2009-01-01

    Human observers take longer to re-direct gaze to a previously fixated location. Although there has been some exploration of the characteristics of inhibition of saccadic return (ISR), the exact mechanisms by which ISR operates are currently unknown. In the framework of accumulation models of response times, in which evidence is integrated over…

  13. Tortuosity of lightning return stroke channels

    NASA Technical Reports Server (NTRS)

    Levine, D. M.; Gilson, B.

    1984-01-01

    Data obtained from photographs of lightning are presented on the tortuosity of return stroke channels. The data were obtained by making piecewise linear fits to the channels, and recording the cartesian coordinates of the ends of each linear segment. The mean change between ends of the segments was nearly zero in the horizontal direction and was about eight meters in the vertical direction. Histograms of these changes are presented. These data were used to create model lightning channels and to predict the electric fields radiated during return strokes. This was done using a computer generated random walk in which linear segments were placed end-to-end to form a piecewise linear representation of the channel. The computer selected random numbers for the ends of the segments assuming a normal distribution with the measured statistics. Once the channels were simulated, the electric fields radiated during a return stroke were predicted using a transmission line model on each segment. It was found that realistic channels are obtained with this procedure, but only if the model includes two scales of tortuosity: fine scale irregularities corresponding to the local channel tortuosity which are superimposed on large scale horizontal drifts. The two scales of tortuosity are also necessary to obtain agreement between the electric fields computed mathematically from the simulated channels and the electric fields radiated from real return strokes. Without large scale drifts, the computed electric fields do not have the undulations characteristics of the data.

  14. Return to the Poles of Mars

    NASA Technical Reports Server (NTRS)

    McCleese, D. J.

    2000-01-01

    The loss of the Mars Polar Lander (MPL) raises the question of when NASA might attempt a return mission to the Polar Regions. This paper describes future opportunities for recovering the science lost with MPL. Additional information can be found in the original extended abstract.

  15. What's the Return on a Tenner Nowadays...?

    ERIC Educational Resources Information Center

    Williams, Sandra

    2001-01-01

    Workplace training at the British offices of Readers' Digest is designed to improve staff skills in communicating with customers. Evaluation of workshops focused on spelling, grammar, and business writing shows that the company is achieving a return on its training investment. (SK)

  16. Exploring Literate Lives: Returning to the Field

    ERIC Educational Resources Information Center

    Henderson, Robyn; Woods, Annette

    2016-01-01

    The challenges of conducting lengthy fieldwork in today's busy academic world have impacted the types of research that are able to be carried out. In particular, traditional educational ethnography has become problematic for research beyond initial doctoral research programs. This article analyzes data collected during a return to the field of a…

  17. Sample Return from the Stardust Mission

    NASA Technical Reports Server (NTRS)

    2006-01-01

    On January 2,2004, the STARDUST spacecraft made a close flyby (236 km) of the nucleus of a comet - Comet Wild 2. During the flyby the spacecraft collected samples of dust from the coma of the comet. These samples were successfully returned to Earth on January 15,2006. After a six month preliminary examination to establish the nature of the returned samples, they will be made available to the general scientific community for study. STARDUST is one of the missions carried out under NASA's Discovery Mission Program. During my talk I will present a brief overview of the scientific goals of the STARDUST mission and describe the mission's design and flight. I will also discuss the reentry and recovery of the Stardust Sample Return Capsule (SRC) in Utah, with an emphasis on those aspects of the recovery important for minimizing the degree of contamination (particularly organic contamination) of the samples. Finally, I will discuss some of the results coming out of the preliminary examination of the returned samples, with an emphasis on the nature of organic materials found in the samples.

  18. 27 CFR 479.51 - Fraudulent return.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 3 2010-04-01 2010-04-01 false Fraudulent return. 479.51 Section 479.51 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE FIREARMS AND AMMUNITION MACHINE GUNS, DESTRUCTIVE DEVICES, AND...

  19. 27 CFR 479.51 - Fraudulent return.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 3 2011-04-01 2010-04-01 true Fraudulent return. 479.51 Section 479.51 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE FIREARMS AND AMMUNITION MACHINE GUNS, DESTRUCTIVE DEVICES, AND...

  20. 27 CFR 479.51 - Fraudulent return.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 3 2014-04-01 2014-04-01 false Fraudulent return. 479.51 Section 479.51 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE FIREARMS AND AMMUNITION MACHINE GUNS, DESTRUCTIVE DEVICES, AND...

  1. 27 CFR 479.51 - Fraudulent return.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 3 2013-04-01 2013-04-01 false Fraudulent return. 479.51 Section 479.51 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE FIREARMS AND AMMUNITION MACHINE GUNS, DESTRUCTIVE DEVICES, AND...

  2. 27 CFR 479.51 - Fraudulent return.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 3 2012-04-01 2010-04-01 true Fraudulent return. 479.51 Section 479.51 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE FIREARMS AND AMMUNITION MACHINE GUNS, DESTRUCTIVE DEVICES, AND...

  3. An Editor's Journey: Return to Haiti

    ERIC Educational Resources Information Center

    Moy, Yvette

    2012-01-01

    This paper recounts the author's story as she returned to Haiti in February to join a building project near Port-Au-Prince and to document efforts by U.S. higher education institutions to help the country rebound from the devastating 2010 earthquake. The author describes how consortiums have been formed in order to support the development of the…

  4. 46 CFR 308.514 - Return premium.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE War Risk Cargo Insurance Ii-Open Policy War Risk Cargo Insurance § 308.514 Return premium. No premium will be... there was a declaration of value at variance with Clause 8, or an error in the application of a rate...

  5. 46 CFR 308.514 - Return premium.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE War Risk Cargo Insurance Ii-Open Policy War Risk Cargo Insurance § 308.514 Return premium. No premium will be... there was a declaration of value at variance with Clause 8, or an error in the application of a rate...

  6. Early Learning: Return on Investment. Annotated Bibliography

    ERIC Educational Resources Information Center

    Hite, Jenny

    2014-01-01

    Today's researchers seek to determine if contemporary pre-K programs provide the strong return on investment found by researchers in the 1960's High/Scope Perry Preschool Program and 1970's North Carolina Abecedarian Project. Research then showed that these two programs created positive academic effects that accompanied their students as they…

  7. NASA returns rocks from a comet.

    PubMed

    Burnett, Don S

    2006-12-15

    Cometary particles returned by the Stardust Discovery Mission are primarily silicate materials of solar system origin. Some of the grains were formed at high temperatures close to the Sun, but then transported far out to the Kuiper belt region of the solar system before being incorporated in the comet. PMID:17170288

  8. 26 CFR 36.3121(l)(10)-3 - Returns.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 15 2011-04-01 2011-04-01 false Returns. 36.3121(l)(10)-3 Section 36.3121(l)(10....3121(l)(10)-3 Returns. (a) The forms prescribed for use in making returns of the taxes imposed by the... returns of its liability under an agreement entered into as provided in § 36.3121(l)(1)-1. Returns of...

  9. 26 CFR 36.3121(l)(10)-3 - Returns.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 15 2012-04-01 2012-04-01 false Returns. 36.3121(l)(10)-3 Section 36.3121(l)(10....3121(l)(10)-3 Returns. (a) The forms prescribed for use in making returns of the taxes imposed by the... returns of its liability under an agreement entered into as provided in § 36.3121(l)(1)-1. Returns of...

  10. 26 CFR 36.3121(l)(10)-3 - Returns.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 15 2010-04-01 2010-04-01 false Returns. 36.3121(l)(10)-3 Section 36.3121(l)(10....3121(l)(10)-3 Returns. (a) The forms prescribed for use in making returns of the taxes imposed by the... returns of its liability under an agreement entered into as provided in § 36.3121(l)(1)-1. Returns of...

  11. 26 CFR 36.3121(l)(10)-3 - Returns.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 15 2014-04-01 2014-04-01 false Returns. 36.3121(l)(10)-3 Section 36.3121(l)(10....3121(l)(10)-3 Returns. (a) The forms prescribed for use in making returns of the taxes imposed by the... returns of its liability under an agreement entered into as provided in § 36.3121(l)(1)-1. Returns of...

  12. 26 CFR 36.3121(l)(10)-3 - Returns.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 26 Internal Revenue 15 2013-04-01 2013-04-01 false Returns. 36.3121(l)(10)-3 Section 36.3121(l)(10....3121(l)(10)-3 Returns. (a) The forms prescribed for use in making returns of the taxes imposed by the... returns of its liability under an agreement entered into as provided in § 36.3121(l)(1)-1. Returns of...

  13. Power and energy dissipation in subsequent return strokes as predicted by a new return stroke model

    NASA Technical Reports Server (NTRS)

    Cooray, Vernon

    1991-01-01

    Recently, Cooray introduced a new return stroke model which is capable of predicting the temporal behavior of the return stroke current and the return stroke velocity as a function of the height along the return stroke channel. The authors employed this model to calculate the power and energy dissipation in subsequent return strokes. The results of these calculations are presented here. It was concluded that a large fraction of the total energy available for the dart leader-subsequent stroke process is dissipated in the dart leader stage. The peak power per unit length dissipated in a subsequent stroke channel element decreases with increasing height of that channel element from ground level. For a given channel element, the peak power dissipation increases with increasing current in that channel element. The peak electrical power dissipation in a typical subsequent return stroke is about 1.5 times 10(exp 11) W. The energy dissipation in a subsequent stroke increases with increasing current in the return stroke channel, and for a typical subsequent stroke, the energy dissipation per unit length is about 5.0 times 10(exp 3) J/m.

  14. 26 CFR 301.6033-4 - Required use of magnetic media for returns by organizations required to file returns under...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 18 2010-04-01 2010-04-01 false Required use of magnetic media for returns by... ADMINISTRATION Information and Returns Returns and Records § 301.6033-4 Required use of magnetic media for... required to file returns under section 6033 on magnetic media. An organization required to file a...

  15. 26 CFR 1.6011-7 - Specified tax return preparers required to file individual income tax returns using magnetic media.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... individual income tax returns using magnetic media. 1.6011-7 Section 1.6011-7 Internal Revenue INTERNAL... tax returns using magnetic media. Individual income tax returns that are required to be filed on magnetic media by tax return preparers under section 6011(e)(3) and § 301.6011-7 of this chapter must...

  16. 26 CFR 1.6011-7 - Specified tax return preparers required to file individual income tax returns using magnetic media.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... individual income tax returns using magnetic media. 1.6011-7 Section 1.6011-7 Internal Revenue INTERNAL... tax returns using magnetic media. Individual income tax returns that are required to be filed on magnetic media by tax return preparers under section 6011(e)(3) and § 301.6011-7 of this chapter must...

  17. 26 CFR 1.6011-7 - Specified tax return preparers required to file individual income tax returns using magnetic media.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... individual income tax returns using magnetic media. 1.6011-7 Section 1.6011-7 Internal Revenue INTERNAL... tax returns using magnetic media. Individual income tax returns that are required to be filed on magnetic media by tax return preparers under section 6011(e)(3) and § 301.6011-7 of this chapter must...

  18. 26 CFR 301.6103(n)-1 - Disclosure of returns and return information in connection with written contracts or agreements...

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... administration purposes. 301.6103(n)-1 Section 301.6103(n)-1 Internal Revenue INTERNAL REVENUE SERVICE... and Returns Returns and Records § 301.6103(n)-1 Disclosure of returns and return information in... administration purposes. (a) General rule. (1) Pursuant to the provisions of section 6103(n) of the...

  19. 26 CFR 301.6103(n)-1 - Disclosure of returns and return information in connection with written contracts or agreements...

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... administration purposes. 301.6103(n)-1 Section 301.6103(n)-1 Internal Revenue INTERNAL REVENUE SERVICE... and Returns Returns and Records § 301.6103(n)-1 Disclosure of returns and return information in... administration purposes. (a) General rule. (1) Pursuant to the provisions of section 6103(n) of the...

  20. 26 CFR 301.6103(n)-1 - Disclosure of returns and return information in connection with written contracts or agreements...

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... administration purposes. 301.6103(n)-1 Section 301.6103(n)-1 Internal Revenue INTERNAL REVENUE SERVICE... and Returns Returns and Records § 301.6103(n)-1 Disclosure of returns and return information in... administration purposes. (a) General rule. (1) Pursuant to the provisions of section 6103(n) of the...

  1. 26 CFR 301.6103(p)(2)(B)-1 - Disclosure of returns and return information by other agencies.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... other agencies. 301.6103(p)(2)(B)-1 Section 301.6103(p)(2)(B)-1 Internal Revenue INTERNAL REVENUE... Information and Returns Returns and Records § 301.6103(p)(2)(B)-1 Disclosure of returns and return information... regulations thereunder, including, if applicable, safeguards imposed by section 6103(p)(4). (d) Records...

  2. 26 CFR 301.6103(p)(4)-1 - Procedures relating to safeguards for returns or return information.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... or return information. 301.6103(p)(4)-1 Section 301.6103(p)(4)-1 Internal Revenue INTERNAL REVENUE... Information and Returns Returns and Records § 301.6103(p)(4)-1 Procedures relating to safeguards for returns..., see § 301.6103(p)(7)-1....

  3. 26 CFR 301.6103(p)(4)-1 - Procedures relating to safeguards for returns or return information.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... or return information. 301.6103(p)(4)-1 Section 301.6103(p)(4)-1 Internal Revenue INTERNAL REVENUE... Information and Returns Returns and Records § 301.6103(p)(4)-1 Procedures relating to safeguards for returns..., see § 301.6103(p)(7)-1....

  4. 26 CFR 301.6103(p)(2)(B)-1 - Disclosure of returns and return information by other agencies.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... other agencies. 301.6103(p)(2)(B)-1 Section 301.6103(p)(2)(B)-1 Internal Revenue INTERNAL REVENUE... Information and Returns Returns and Records § 301.6103(p)(2)(B)-1 Disclosure of returns and return information... regulations thereunder, including, if applicable, safeguards imposed by section 6103(p)(4). (d) Records...

  5. 26 CFR 301.6103(l)-1 - Disclosure of returns and return information for purposes other than tax administration.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... for purposes other than tax administration. 301.6103(l)-1 Section 301.6103(l)-1 Internal Revenue... ADMINISTRATION Information and Returns Returns and Records § 301.6103(l)-1 Disclosure of returns and return... provisions of section 6103(l) of the Internal Revenue Code, the term agent includes a contractor....

  6. 26 CFR 301.6103(l)-1 - Disclosure of returns and return information for purposes other than tax administration.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... for purposes other than tax administration. 301.6103(l)-1 Section 301.6103(l)-1 Internal Revenue... ADMINISTRATION Information and Returns Returns and Records § 301.6103(l)-1 Disclosure of returns and return... provisions of section 6103(l) of the Internal Revenue Code, the term agent includes a contractor....

  7. 26 CFR 301.6103(l)-1 - Disclosure of returns and return information for purposes other than tax administration.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... for purposes other than tax administration. 301.6103(l)-1 Section 301.6103(l)-1 Internal Revenue... ADMINISTRATION Information and Returns Returns and Records § 301.6103(l)-1 Disclosure of returns and return... provisions of section 6103(l) of the Internal Revenue Code, the term agent includes a contractor....

  8. 26 CFR 301.6103(l)-1 - Disclosure of returns and return information for purposes other than tax administration.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... for purposes other than tax administration. 301.6103(l)-1 Section 301.6103(l)-1 Internal Revenue... ADMINISTRATION Information and Returns Returns and Records § 301.6103(l)-1 Disclosure of returns and return... provisions of section 6103(l) of the Internal Revenue Code, the term agent includes a contractor....

  9. 26 CFR 301.6103(l)-1 - Disclosure of returns and return information for purposes other than tax administration.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... for purposes other than tax administration. 301.6103(l)-1 Section 301.6103(l)-1 Internal Revenue... ADMINISTRATION Information and Returns Returns and Records § 301.6103(l)-1 Disclosure of returns and return... provisions of section 6103(l) of the Internal Revenue Code, the term agent includes a contractor....

  10. 26 CFR 1.6011-7 - Specified tax return preparers required to file individual income tax returns using magnetic media.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... individual income tax returns using magnetic media. 1.6011-7 Section 1.6011-7 Internal Revenue INTERNAL... tax returns using magnetic media. Individual income tax returns that are required to be filed on magnetic media by tax return preparers under section 6011(e)(3) and § 301.6011-7 of this chapter must...

  11. 26 CFR 301.6103(p)(4)-1 - Procedures relating to safeguards for returns or return information.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... or return information. 301.6103(p)(4)-1 Section 301.6103(p)(4)-1 Internal Revenue INTERNAL REVENUE... Information and Returns Returns and Records § 301.6103(p)(4)-1 Procedures relating to safeguards for returns..., see § 301.6103(p)(7)-1....

  12. 26 CFR 301.6103(p)(4)-1 - Procedures relating to safeguards for returns or return information.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... or return information. 301.6103(p)(4)-1 Section 301.6103(p)(4)-1 Internal Revenue INTERNAL REVENUE... Information and Returns Returns and Records § 301.6103(p)(4)-1 Procedures relating to safeguards for returns..., see § 301.6103(p)(7)-1....

  13. 26 CFR 301.6103(p)(2)(B)-1 - Disclosure of returns and return information by other agencies.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... other agencies. 301.6103(p)(2)(B)-1 Section 301.6103(p)(2)(B)-1 Internal Revenue INTERNAL REVENUE... Information and Returns Returns and Records § 301.6103(p)(2)(B)-1 Disclosure of returns and return information... regulations thereunder, including, if applicable, safeguards imposed by section 6103(p)(4). (d) Records...

  14. 26 CFR 301.6103(p)(2)(B)-1 - Disclosure of returns and return information by other agencies.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... other agencies. 301.6103(p)(2)(B)-1 Section 301.6103(p)(2)(B)-1 Internal Revenue INTERNAL REVENUE... Information and Returns Returns and Records § 301.6103(p)(2)(B)-1 Disclosure of returns and return information... regulations thereunder, including, if applicable, safeguards imposed by section 6103(p)(4). (d) Records...

  15. 26 CFR 301.6103(p)(2)(B)-1 - Disclosure of returns and return information by other agencies.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... other agencies. 301.6103(p)(2)(B)-1 Section 301.6103(p)(2)(B)-1 Internal Revenue INTERNAL REVENUE... Information and Returns Returns and Records § 301.6103(p)(2)(B)-1 Disclosure of returns and return information... regulations thereunder, including, if applicable, safeguards imposed by section 6103(p)(4). (d) Records...

  16. 26 CFR 301.6103(p)(4)-1 - Procedures relating to safeguards for returns or return information.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... or return information. 301.6103(p)(4)-1 Section 301.6103(p)(4)-1 Internal Revenue INTERNAL REVENUE... Information and Returns Returns and Records § 301.6103(p)(4)-1 Procedures relating to safeguards for returns..., see § 301.6103(p)(7)-1....

  17. Drought length properties for periodic-stochastic hydrologic data

    NASA Astrophysics Data System (ADS)

    Cancelliere, Antonino; Salas, Jose D.

    2004-02-01

    Extreme droughts may be characterized by their duration, severity (magnitude or intensity), spatial extent, and frequency or return period. Comparing the time series of water supply and water demand and analyzing droughts based on the theory of runs may determine these characteristics. This study is focused on drought analysis where the underlying water supply process is periodic stochastic, such as for monthly streamflows. The probability mass function (pmf) of drought length and associated low-order moments are derived assuming a periodic simple Markov chain. The derived pmf allows estimating the occurrence probability of droughts of a given length and its return period. The applicability of the drought formulations has been illustrated using a variety of water supply series such as monthly and weekly precipitation, monthly streamflows, the Palmer hydrologic drought index, and the standardized precipitation index. The results obtained confirm the validity of the analytical derivations for drought lengths and associated return periods. The overall conclusion of the study is that simple definitions of droughts enables one characterizing droughts using stochastic approaches and analytical derivations. They are particularly useful for drought analysis because the limited hydrologic records that are generally available do not allow observing many drought events of a particular duration and, in fact, extremely long droughts may not even be observable from the historical sample. This hinders the applicability of an inferential approach for finding the probability distributions of drought lengths and their associated return periods because it is either impractical or not feasible.

  18. Familial Periodic Paralyses

    MedlinePlus

    ... NINDS NINDS Familial Periodic Paralyses Information Page Synonym(s): Periodic Paralyses Table of Contents (click to jump to sections) What are Familial Periodic Paralyses? Is there any treatment? What is the ...

  19. Multiple scattering lidar returns from stratus clouds

    NASA Technical Reports Server (NTRS)

    Hutt, D. L.; Bissonnette, L. R.

    1992-01-01

    Multiple scattering lidar returns from stratus clouds were measured using a multi-field-of-view (MFOV) lidar operating at 1.054 microns. The detector consists of four concentric silicon photodiodes which define half-angle fields of view (FOV) of 3.8, 12.5, 25 and 38.5 mrad. The central FOV receives the conventional lidar signal, while the outer FOV's receive only multiply scattered contributions. The ratios of the signals in the outer FOV's to the signal in the central FOV is an indication of the lateral spreading of the scattered component of the laser pulse as it propagates through the cloud. MFOV lidar returns from stratus clouds measured between October 1991 and March 1992 can be divided into two distinct types, those with large multiple scattering ratios and those with small ratios. An example of each type of return is shown. Both measurements were made at an elevation angle of 45 degrees. Clouds with small multiple scattering signals probably have a high concentration of much larger particles on the order of hundreds of micrometers in size. This is a typical size range for suspended ice crystals or precipitations. Stratus clouds often have a high concentration of ice crystals even when there is no precipitation. Large ice crystals would give smaller signals in the outer FOV's because much of the scattered intensity is contained in a narrow diffraction peak with an angular width on the order of milliradians. The result is that for a given extinction, many more orders of scattering are required for the laser pulse to spread out. So far we have not been able to do simulations of MFOV lidar returns from ice crystal clouds because of uncertainties about the phase function of the crystals, particularly the magnitude of the backscatter peak at 180 degrees. On two occasions, MFOV lidar returns measured just prior to snowfall, showed a striking vertical profile. An example is shown. From 900 to 1300m, the multiply scattered signals are negligible compared to the

  20. Return to the Moon: A New Strategic Evaluation

    NASA Technical Reports Server (NTRS)

    Lowman, Paul D., Jr.

    1999-01-01

    This paper reviews the value of a new lunar program, initially robotic and eventually manned, in the light of developments since the 1991 Synthesis Group study of the Space Exploration Initiative. The objective is to evaluate a return to the Moon in comparison to proposed Mars programs as a focus for American space exploration with humans in the next century. The Moon is demonstrably accessible, hospitable, useful, and interesting. Lunar programs are inherently faster and less risky from a programmatic viewpoint than comparable Mars programs such as Mars Direct. The dominant reason for a resumption of manned lunar missions, focussed on a single site such as Grimaldi, is to rebuild the infrastructure for missions beyond earth orbit, the last of which was in 1972. A transitional program, corresponding to the 10 Gemini missions that bridged the gap between Mercury and Apollo, was considered absolutely essential by the Synthesis Group. Further justification for a return to the Moon is the demonstrated feasibility of a robotic lunar observatory, concentrating on optical and infrared interferometry. Many unsolved scientific questions about the Moon itself remain, and could be investigated using telerobotic lunar rovers even before the return of humans. Mars is unquestionably more interesting scientifically and far more hospitable for long-term colonization. A new lunar program would be the most effective possible preparation for the human exploration, settlement, and eventually the terraforming of Mars. Lunar and Mars programs are complementary, not competitive. Both can be justified in the most fundamental terms as beginning the dispersal of the human species against uncontrollable natural disasters, cometary or asteroidal impacts in particular, to which mankind is vulnerable while confined to a single planet. Three specific programs are recommended for the 2001-2010 period: Ice Prospectors, to evaluate polar ice or hydrogen deposits; a robotic lunar observatory; and a

  1. Return to the Moon: A New Strategic Evaluation

    NASA Technical Reports Server (NTRS)

    Lowman, Paul D., Jr.

    1999-01-01

    This paper reviews the value of a new lunar program, initially robotic and eventually manned, in the light of developments since the 1991 Synthes Group study of the Space Exploration Initiative. The objective is to evaluate a return to the Moon in comparison to proposed Mars programs as a focus for American space exploration with humans in the next century. The Moon is demonstrably accessible, hospitable, useful, and interesting. Lunar programs are inherently faster and less risky from a programmatic viewpoint than comparable Mars programs such as Mars Direct. The dominant reason for a resumption of manned lunar missions, focused on a single site such as Grimaldi, is to rebuild the infrastructure for missions beyond Earth orbit, the last of which was in 1972. A transitional prograrr@ corresponding to the 10 Gemini missions that bridged the gap between Mercury and Apollo, was considered absolutely essential by the Synthesis Group. Further justification for a return to the Moon is the demonstrated feasibility of a robotic lunar observatory, concentrating on optical and infrared interferometry. Many unsolved scientific questions about the Moon itself remain, and could be investigated using telerobotic lunar rovers even before the return of humans. Mars is unquestionably more interesting scientifically and far more hospitable for long-term colonization. A new lunar program would be the most effective possible preparation for the human exploration, settlement and eventually the terraforming of Mars. Lunar and Mars programs are complementary, not competitive. Both can be justified in the most fundamental terms as beginning the dispersal of the human species against uncontrollable natural disasters, cometary or asteroidal impacts in particular, to which mankind is vulnerable while confined to a single planet. Three specific programs are recommended for the 2001-2010 period: Ice Prospectors, to evaluate polar ice or hydrogen deposits; a robotic lunar observatory; and a

  2. Return to the Moon: A New Strategic Evaluation

    NASA Technical Reports Server (NTRS)

    Lowman, Paul D., Jr.

    1999-01-01

    This paper reviews the value of a new lunar program, initially robotic and eventually manned, in the light of developments since the 1991 Synthes Group study of the Space Exploration Initiative. The objective is to evaluate a return to the Moon in comparison to proposed Mars programs as a focus for American space exploration with humans in the next century. The Moon is demonstrably accessible, hospitable, useful, and interesting. Lunar programs are inherently faster and less risky from a programmatic viewpoint than comparable Mars programs such as Mars Direct. The dominant reason for a resumption of manned lunar missions, focused on a single site such as Grimaldi, is to rebuild the infrastructure for missions beyond Earth orbit, the last of which was in 1972. A transitional program, corresponding to the 10 Gemini missions that bridged the gap between Mercury and Apollo, was considered absolutely essential by the Synthesis Group. Further justification for a return to the Moon is the demonstrated feasibility of a robotic lunar observatory, concentrating on optical and infrared interferometry. Many unsolved scientific questions about the Moon itself remain, and could be investigated using telerobotic lunar rovers even before the return of humans. Mars is unquestionably more interesting scientifically and far more hospitable for long-term colonization. A new lunar program would be the most effective possible preparation for the human exploration, settlement and eventually the terraforming of Mars. Lunar and Mars programs are complementary, not competitive. Both can be justified in the most fundamental terms as beginning the dispersal of the human species against uncontrollable natural disasters, cometary or asteroidal impacts in particular, to which mankind is vulnerable while confined to a single planet. Three specific programs are recommended for the 2001-2010 period: Ice Prospectors, to evaluate polar ice or hydrogen deposits; a robotic lunar observatory; and a

  3. Negotiating a successful return to work program.

    PubMed

    Di Guida, A W

    1995-02-01

    This article has examined selected reasons why companies resist implementation of return to work programs. The reasons include many fears that companies can readily justify. Nearly all the fears can be eliminated when the occupational health nurse applies both nursing and management principles. As a specialized line manager in the company, with a specialty in people and systems management, the occupational health nurse is the most likely person to plan and implement a successful program. To design, implement, and manage the plan to a successful end, the occupational health nurse must enhance skills in language, salesmanship, and quantifying results. Success must be measured in both people and dollar terms to have relevance to the company, its bottom line, and its employees. People results, the harder of the two to measure, have value in helping to establish positive attitudes of program participants toward the company. People results also help prevent the development of disability syndrome by ill or injured employees by keeping them connected to work and productivity. People results also can be measured by the change in culture the return to work program is likely to produce among managers and employees. The resulting culture will reflect a sense of caring by the company about employees, and expectation that manipulation of the company by opportunists will be reduced, as scarce company resources will be conserved. The early return to work program is managed within employee capabilities in a therapeutic environment during the recovery process. In the long term, financial success of the return to work program can be measured by reduced costs per claim annually. Using the nursing, management, financial, and marketing principles discussed in this article, the occupational health nurse can improve chances of negotiating implementation of a successful early return to work program. PMID:7779181

  4. Expected Time to Return to Athletic Participation Following Stress Fracture in Division I Collegiate Athletes

    PubMed Central

    Jamieson, Marissa; Everson, Sonsecharae; Siegel, Courtney; Miller, Timothy Lee

    2016-01-01

    Objectives: The objective of this study was to evaluate and determine the expected time to return to athletic participation in Division I collegiate Track and Field athletes. Methods: All stress fractures diagnosed in athletes on a single Division I collegiate men’s and women’s track and field/ cross-country team were recorded over a 4-year period. Site and severity of the injury were recorded and graded based on the Kaeding-Miller Classification System for stress fractures. Time to return to full unrestricted athletic participation was recorded for each athlete and correlated with the site and severity grade of the injury. Time to return to athletic participation was also analyzed for gender differences. Results: Fifty-seven stress fractures were diagnosed in 38 athletes over a 4-year period. Thirty-seven of these injuries occurred in women; twenty in men. Mean time to return to participation in women was 13.9 weeks and 11.2 weeks in men. There were 10 athletes who sustained recurrent or multiple stress fractures. Thirty-three stress fractures occurred in the tibia, and 10 occurred in the 2nd through 4th metatarsals. Three occurred in the 5th metatarsal, 6 in the tarsal bones (2 navicular), and 5 in the pelvis. Mean times to return to athletic activity based on site of injury and with extreme outliers removed were as follows: tibia- 13.3 weeks, 2nd through 4th metatarsals- 11.7 weeks, 5th metatarsal- 11.7 weeks, tarsals- 12.1 weeks, and pelvis- 13.0 weeks. There were 31 grade 2 stress fractures, 11 grade 3 stress fractures, and two grade 5 stress fractures that occurred bilaterally in the same patient. Mean times to return to athletic participation again with extreme outliers excluded were as follows: Grade 2- 12.3 weeks, Grade 3- 14.1 weeks, and Grade 5- 17 weeks. There were no Grade 4 (displaced) stress fractures diagnosed in this cohort of patients. Conclusion: Stress injuries to bone occur frequently in track and field athletes. Based on data collected

  5. OSIRIS-REx, Returning the Asteroid Sample

    NASA Technical Reports Server (NTRS)

    Ajluni, Thomas, M.; Everett, David F.; Linn, Timothy; Mink, Ronald; Willcockson, William; Wood, Joshua

    2015-01-01

    This paper addresses the technical aspects of the sample return system for the upcoming Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer (OSIRIS-REx) asteroid sample return mission. The overall mission design and current implementation are presented as an overview to establish a context for the technical description of the reentry and landing segment of the mission.The prime objective of the OSIRIS-REx mission is to sample a primitive, carbonaceous asteroid and to return that sample to Earth in pristine condition for detailed laboratory analysis. Targeting the near-Earth asteroid Bennu, the mission launches in September 2016 with an Earth reentry date of September 24, 2023.OSIRIS-REx will thoroughly characterize asteroid Bennu providing knowledge of the nature of near-Earth asteroids that is fundamental to understanding planet formation and the origin of life. The return to Earth of pristine samples with known geologic context will enable precise analyses that cannot be duplicated by spacecraft-based instruments, revolutionizing our understanding of the early Solar System. Bennu is both the most accessible carbonaceous asteroid and one of the most potentially Earth-hazardous asteroids known. Study of Bennu addresses multiple NASA objectives to understand the origin of the Solar System and the origin of life and will provide a greater understanding of both the hazards and resources in near-Earth space, serving as a precursor to future human missions to asteroids.This paper focuses on the technical aspects of the Sample Return Capsule (SRC) design and concept of operations, including trajectory design and reentry retrieval. Highlights of the mission are included below.The OSIRIS-REx spacecraft provides the essential functions for an asteroid characterization and sample return mission: attitude control propulsion power thermal control telecommunications command and data handling structural support to ensure successful

  6. On the return period statistics of magnetic storms and their implications.

    NASA Astrophysics Data System (ADS)

    Freeman, M. P.; Horne, R. B.; Daws, M.; Wilson, P. S.

    2003-04-01

    Magnetic storms are globally coherent non-secular variations of the geomagnetic field that have been identified as a natural environmental hazard with adverse effects on radio communications, satellite operations, electrical power distribution, etc. Thus it is desirable to forecast the occurrence of magnetic storms to mitigate their impact. To this end, we have analysed the probability density function (PDF) of magnetic storm duration, non-storm duration, and waiting time between storm onsets, for two objective definitions of a magnetic storm based on historical precedent. In the first definition, a magnetic storm is defined as a classic extreme event - the interval for which a relevant geomagnetic measure (the -Dst index) is above a given threshold, c. The PDF of storm duration, non-storm duration, and waiting time between storm onsets are all found to be truncated power laws, independent of threshold. Thus, under this definition, magnetic storms have no characteristic duration or recurrence time between ˜ 1 h and ˜ 100 h. In the second definition, we show evidence that the extreme events of the first definition are part of a longer coherent structure in the time series such that a magnetic storm can alternatively be defined as the interval for which the -Dst index is above a given threshold b and the maximum -Dst is above a second, higher threshold c. Over a region of the two-threshold parameter space \\{b, c\\}, the PDF of waiting times between storm onsets in 3-year samples is found to be a random stationary (Poisson) process with a Poisson statistic that varies with the solar cycle, and the PDF of storm durations is peaked at 20-30 h. The analysis raises an interesting general question as to the occurrence properties of abstract extrema (e.g., gale force winds) compared to those of physical extreme events (e.g., hurricanes?). Moreover, an interesting similarity between the occurrence pattern of repeatable magnetic storms and of solar flares is noted.

  7. The ionized electron return phenomenon of Rydberg atom in crossed-fields

    NASA Astrophysics Data System (ADS)

    Dong, Chengwei; Wang, Peijie; Du, Mengli; Uzer, Turgay; Lan, Yueheng

    2016-05-01

    Rydberg atom is highly excited with one valence electron being in a high quantum state, which is very far away from the nucleus. The energy level is similar to that of the hydrogen atom. Introducing externally perpendicular electric and magnetic fields breaks the rotation symmetry and the traditional view is that the ionized electron crosses from the bound into the unbound region and will never return. However, we find that when the field is strong enough, the electron does not move off to infinity and there is a certain possibility of return. Three new periodic orbits are found by the variational method and the physical significance of the phenomenon is also discussed.

  8. 12 CFR 229.31 - Returning bank's responsibility for return of checks.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... test, and the deadline for return under the U.C.C. and Regulation J (12 CFR part 210), are extended by... THE FEDERAL RESERVE SYSTEM (CONTINUED) AVAILABILITY OF FUNDS AND COLLECTION OF CHECKS (REGULATION...

  9. 12 CFR 229.31 - Returning bank's responsibility for return of checks.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... test, and the deadline for return under the U.C.C. and Regulation J (12 CFR part 210), are extended by... THE FEDERAL RESERVE SYSTEM AVAILABILITY OF FUNDS AND COLLECTION OF CHECKS (REGULATION CC)...

  10. 12 CFR 229.31 - Returning bank's responsibility for return of checks.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... test, and the deadline for return under the U.C.C. and Regulation J (12 CFR part 210), are extended by... THE FEDERAL RESERVE SYSTEM AVAILABILITY OF FUNDS AND COLLECTION OF CHECKS (REGULATION CC)...

  11. 12 CFR 229.31 - Returning bank's responsibility for return of checks.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... test, and the deadline for return under the U.C.C. and Regulation J (12 CFR part 210), are extended by... THE FEDERAL RESERVE SYSTEM (CONTINUED) AVAILABILITY OF FUNDS AND COLLECTION OF CHECKS (REGULATION...

  12. 12 CFR 229.31 - Returning bank's responsibility for return of checks.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... test, and the deadline for return under the U.C.C. and Regulation J (12 CFR part 210), are extended by... THE FEDERAL RESERVE SYSTEM AVAILABILITY OF FUNDS AND COLLECTION OF CHECKS (REGULATION CC)...

  13. The Potential of the PSI and SCL-90R Subscales To Predict Post-Intake Client Return at a University Counseling Center.

    ERIC Educational Resources Information Center

    McCabe, Kathryn A.; Gold, Joshua M.

    This study sought to identify differential psychological symptom status and demographic variability between male/female returners and non-returners to a university counseling center. Data were collected during intake interviews over a 9-month period (N=261). The information analyzed consisted of nine distinct subscale scores of the Symptomatic…

  14. Mars rover sample return mission utilizing in situ production of the return propellants

    NASA Technical Reports Server (NTRS)

    Bruckner, A. P.; Nill, L.; Schubert, H.; Thill, B.; Warwick, R.

    1993-01-01

    This paper presents an unmanned Mars sample return mission that utilizes propellants manufactured in situ from the Martian atmosphere for the return trip. A key goal of the mission is to demonstrate the considerable benefits that can be realized through the use of indigenous resources and to test the viability of this approach as a precursor to manned missions to Mars. Two in situ propellant combinations, methane/oxygen and carbon monoxide/oxygen, are compared to imported terrestrial hydrogen/oxygen within a single mission architecture, using a single Earth launch vehicle. The mission is assumed to be launched from Earth in 2003. Upon reaching Mars, the landing vehicle aerobrakes, deploys a small satellite, and lands on the Martian surface. Once on the ground, the propellant production unit is activated, and the product gases are liquefied and stored in the empty tanks of the Earth Return Vehicle (ERV). Power for these activities is provided by a dynamic isotope power system. A semiautonomous rover, powered by the indigenous propellants, gathers between 25 and 30 kg of soil and rock samples which are loaded aboard the ERV for return to Earth. After a surface stay time of approximately 1.5 years, the ERV leaves Mars for the return voyage to Earth. When the vehicle reaches the vicinity of Earth, the sample return capsule detaches, and is captured and circularized in LEO via aerobraking maneuvers.

  15. Microscopic return point memory in Co/Pd multilayer films

    SciTech Connect

    Seu, K.A.; Su, R.; Roy, S.; Parks, D.; Shipton, E.; Fullerton, E.E.; Kevan, S.D.

    2009-10-01

    We report soft x-ray speckle metrology measurements of microscopic return point and complementary point memory in Co/Pd magnetic films having perpendicular anisotropy. We observe that the domains assemble into a common labyrinth phase with a period that varies by nearly a factor of two between initial reversal and fields near saturation. Unlike previous studies of similar systems, the ability of the film to reproduce its domain structure after magnetic cycling through saturation varies from loop to loop, from position to position on the sample, and with the part of the speckle pattern used in the metrology measurements. We report the distribution of memory as a function of field and discuss these results in terms of the reversal process.

  16. [Return scholarship of the Universidad Peruana Cayetano Heredia].

    PubMed

    Guerra, Humberto

    2010-09-01

    Developing countries suffer from brain drain for many decades. Industrialized countries have raised their barriers against immigrants, but have created mechanisms to attract foreign professionals, with aggressive policies to capture talents, in an effort to increase their competitiveness. To mitigate the effects of the migration of scientists, the Universidad Peruana Cayetano Heredia has created its own "return scholarship" about 12 years ago, and has repatriated 12 scientists through it. The funds invested in attracting the scholars total U.S. $333,540.00 and they have secured U.S. $9,249,828.42 in research funds during the same period, a figure over 27 times higher. They have published 8 articles in national journals, 68 internationally, and trained 29 undergraduate and 20 graduate students as Thesis Tutors. Other universities and institutions of our countries can emulate this successful experience, which is still evolving. PMID:21152736

  17. Returners and explorers dichotomy in human mobility.

    PubMed

    Pappalardo, Luca; Simini, Filippo; Rinzivillo, Salvatore; Pedreschi, Dino; Giannotti, Fosca; Barabási, Albert-László

    2015-01-01

    The availability of massive digital traces of human whereabouts has offered a series of novel insights on the quantitative patterns characterizing human mobility. In particular, numerous recent studies have lead to an unexpected consensus: the considerable variability in the characteristic travelled distance of individuals coexists with a high degree of predictability of their future locations. Here we shed light on this surprising coexistence by systematically investigating the impact of recurrent mobility on the characteristic distance travelled by individuals. Using both mobile phone and GPS data, we discover the existence of two distinct classes of individuals: returners and explorers. As existing models of human mobility cannot explain the existence of these two classes, we develop more realistic models able to capture the empirical findings. Finally, we show that returners and explorers play a distinct quantifiable role in spreading phenomena and that a correlation exists between their mobility patterns and social interactions. PMID:26349016

  18. Returners and explorers dichotomy in human mobility

    NASA Astrophysics Data System (ADS)

    Pappalardo, Luca; Simini, Filippo; Rinzivillo, Salvatore; Pedreschi, Dino; Giannotti, Fosca; Barabási, Albert-László

    2015-09-01

    The availability of massive digital traces of human whereabouts has offered a series of novel insights on the quantitative patterns characterizing human mobility. In particular, numerous recent studies have lead to an unexpected consensus: the considerable variability in the characteristic travelled distance of individuals coexists with a high degree of predictability of their future locations. Here we shed light on this surprising coexistence by systematically investigating the impact of recurrent mobility on the characteristic distance travelled by individuals. Using both mobile phone and GPS data, we discover the existence of two distinct classes of individuals: returners and explorers. As existing models of human mobility cannot explain the existence of these two classes, we develop more realistic models able to capture the empirical findings. Finally, we show that returners and explorers play a distinct quantifiable role in spreading phenomena and that a correlation exists between their mobility patterns and social interactions.

  19. STARDUST: finessing expensive cometary sample returns.

    PubMed

    Brownlee, D E; Tsou, P; Atkins, K L; Yen, C W; Vellinga, J M; Price, S; Clark, B C

    1996-01-01

    The STARDUST Discovery mission will collect samples of cometary coma and interstellar dust and return them to Earth. Five years after launch in February 1999, coma dust in the 1- to 100-micrometers size range will be captured by impact into ultra-low-density silica aerogel during a 6 kms-1 flyby of Comet Wild 2. The returned samples will be investigated at laboratories where the most critical information on these primitive materials is retained. The Jet Propulsion Laboratory will provide project management with Lockheed Martin Astronauts as the spacecraft industrial partner. STARDUST management will aggressively and innovatively achieve cost control through the use of Total Quality Management principles, the chief of which will be organization in a Project Engineering and Integration Team that "flattens" the traditional hierarchical structure by including all project elements from the beginning, in a concurrent engineering framework focusing on evolving Integrated Mission Capability. PMID:11540764

  20. Splenic Abscesses in a Returning Traveler

    PubMed Central

    Guo, Richard F.; Wong, Frances L.; Perez, Mario L.

    2015-01-01

    Burkholderia, an aerobic gram-negative rod, is the causative organism behind melioidosis and is a common soil and water organism found predominantly in South-East Asia. We report the case of a 68 year-old man returning from an extended trip to the Philippines, with splenic hypodense lesions on abdominal computer tomography scan, later confirmed to be culture-positive for Burkholderia pseudomallei. The patient was treated with a course of intravenous ceftazidime followed by eradication therapy with oral doxycycline and trimethoprim-sulfamethoxazole. He recovered with complete resolution of symptoms at follow up. In a returning traveler from an endemic area, melioidosis should be considered as part of the differential for any febrile illness with abscesses. PMID:25874071

  1. Return current in encephalography. Variational principles.

    PubMed

    Heller, L

    1990-03-01

    The encephalographic problem of finding the electric potential V and the return current associated with any assumed primary current, Jp, is put in the form of a variational principle. With Jp and the conductivity specified, the correct V is one which makes an integral quantity P[V] a maximum. The terms in P[V] are related to the rates at which work is done by the electric field on the primary and return currents. It is shown that there is a unique solution for the electric field, and it satisfies the conservation of energy; this condition can serve as a check on any numerical solution. With the conductivity a different constant in different regions, the variational principle is recast in terms of the charge density on the surfaces of discontinuity. An iteration-variation method for finding the solution is outlined, and possible computational advantages over other approaches are discussed. PMID:2306503

  2. Near-Earth Asteroid Returned Sample (NEARS)

    NASA Technical Reports Server (NTRS)

    Shoemaker, Eugene M.; Cheng, Andrew F.

    1994-01-01

    The concept of the Near-Earth Asteroid Returned Sample (NEARS) mission is to return to Earth 10-100 g from each of four to six sites on a near-Earth asteroid and to perform global characterization of the asteroid and measure mass, volume, and density to ten percent. The target asteroid for the mission is 4660 Nereus, probably a primitive C-type asteroid, with the alternate target being 1989ML, an extremely accessible asteroid of unknown type. Launch dates will be 1998, 2000, 2002, and 2004 on the Delta II-7925 launch vehicle. The mission objectives are three-fold. (1) Provide first direct and detailed petrological, chemical, age, and isotopic characterization of a near-Earth asteroid and relate it to terrestrial, lunar, and meteoritic materials. (2) Sample the asteroid regolith and characterize any exotic fragments. (3) Identify heterogeneity in the asteroid's isotopic properties, age, and elemental chemistry.

  3. Organic Contamination Standards for Mars Sample Return

    NASA Astrophysics Data System (ADS)

    Pugel, D. E.; Conley, Catharine

    Collecting samples from Mars and bringing them to Earth for study has long been an objective of planetary exploration, among other reasons because this allows for the application of the most sensitive instruments to detect biosignatures and other indications of possible Mars life. Understanding terrestrial contamination that could be introduced into Mars samples and confound life detection measurements is an essential aspect of the investigative process. Defining quantitative limits on terrestrial organic contamination is necessary for planetary protection purposes, to ensure high confidence in a putative detection of `Mars life' or possible biohazards in samples after return to Earth. As reported here, NASA's Office of Planetary Protection is initiating a process to establish appropriate limits and controls on organic contamination introduced into Mars samples that will be collected and cached by the Mars 2020 mission for possible future return to Earth.

  4. Returners and explorers dichotomy in human mobility

    PubMed Central

    Pappalardo, Luca; Simini, Filippo; Rinzivillo, Salvatore; Pedreschi, Dino; Giannotti, Fosca; Barabási, Albert-László

    2015-01-01

    The availability of massive digital traces of human whereabouts has offered a series of novel insights on the quantitative patterns characterizing human mobility. In particular, numerous recent studies have lead to an unexpected consensus: the considerable variability in the characteristic travelled distance of individuals coexists with a high degree of predictability of their future locations. Here we shed light on this surprising coexistence by systematically investigating the impact of recurrent mobility on the characteristic distance travelled by individuals. Using both mobile phone and GPS data, we discover the existence of two distinct classes of individuals: returners and explorers. As existing models of human mobility cannot explain the existence of these two classes, we develop more realistic models able to capture the empirical findings. Finally, we show that returners and explorers play a distinct quantifiable role in spreading phenomena and that a correlation exists between their mobility patterns and social interactions. PMID:26349016

  5. Palaeo-pollution from mining activities in the Vosges Mountains: 1000 years and still bioavailable.

    PubMed

    Mariet, Anne-Lise; de Vaufleury, Annette; Bégeot, Carole; Walter-Simonnet, Anne-Véronique; Gimbert, Frédéric

    2016-07-01

    Mining and smelting activities have contaminated the environment with trace metals (TMs) at a worldwide scale for at least two millennia. A combination of chemical approaches and active biomonitoring was performed to analyse the environmental availability and bioavailability of TM palaeo-pollution in a former PbAg mining district in the Vosges Mountains, France. Along a soil TM contamination gradient that covered eight stations, including two archaeological mining sites, the toxicokinetics of six TMs (Pb, Cd, As, Ag, Co, Sb) in the snail Cantareus aspersus revealed that palaeo-pollution from the studied sites remains bioavailable. This study provides the first data on the accumulation kinetics of Ag and Co for C. aspersus. The environmental availability of the TMs was estimated with three chemical extraction methods (aqua regia, EDTA 50 mM, CaCl2 10 mM). Univariate regression analyses showed that EDTA extraction is the best method for estimating the bioavailability of Pb, As, Ag, Co and Sb to snails. None of the three extractants was efficient for Cd. A multivariate analysis of bioaccumulation data revealed that TM bioavailability and transfer were modulated by exposure sources (soil, humus and vegetation) rather than by soil physico-chemical characteristics. Hence, although the deposition of mining wastes dates back several centuries, these wastes still represent a source of contamination that must be considered to develop relevant site management and environmental risk assessment. PMID:27131817

  6. Preliminary evidence for a 1000-year-old tsunami in the South China Sea

    PubMed Central

    Sun, Liguang; Zhou, Xin; Huang, Wen; Liu, Xiaodong; Yan, Hong; Xie, Zhouqing; Wu, Zijun; Zhao, Sanping; Da Shao; Yang, Wenqing

    2013-01-01

    The risk of large, devastating tsunamis in the South China Sea and its surrounding coastal region is commonly underestimated or unrecognized due to the difficulty of differentiating tsunami from storm deposits. As a consequence, few convincing records have documented tsunami deposits in this region. Here we report preliminary evidence from Xisha Islands in the South China Sea for a large tsunami around AD 1024. Sand layers in lake sediment cores and their geochemical characteristics indicate a sudden deposition event around AD 1024, temporally consistent with a written record of a disastrous event characterized by high waves in AD 1076. Heavy coral and shell fossils, which are older than AD 1024, deposited more than 200 meters into the island, further support the occurrence of a high-energy event such as a tsunami or an unusually large storm. Our results underscore the importance of acknowledging and understanding the tsunami hazard in this area. PMID:23575432

  7. SN 1006 at Age 1000 Years: Dazzling Star to Puzzling Remnant

    NASA Astrophysics Data System (ADS)

    Winkler, P. F.

    The supernova of 1006 C.E. was probably the brightest star everrecorded in human history, with documented sightings by northern observers the world over despite its location at Dec (1006) = -38°. Identification of its remnant did not occur until 1965, largely because it is located in a sparse environment far above the Galactic plane and is thus quite faint. With the power of modern instrumentation, this relatively pristine and unabsorbed location has proved to be a boon as astronomers have examined the SN 1006 remnant in multiple energy bands. Diffuse acceleration at the outer shocks produce TeV electrons, whose synchrotron radiation seen in radio and X-ray bands gives strong circumstantial evidence for cosmic ray production in these same shocks. Optical emission occurs exclusively in the Balmer lines of hydrogen. Proper motion measurements of the delicate filaments along the limb, together with the shock velocity determined from Balmer-line profiles, give a precise distance of 2.2 kpc. Absorption-line spectra from several background UV sources have enabled the mapping of Si, Ca, and Fe ejecta within the SN 1006 shell. I review how the combination of medieval records and modern observations are helping astronomers understand SN 1006 as a ``typical" Type Ia supernova remnant, and highlight some mysteries that still remain.

  8. Isotopic studies in returned lunar samples

    NASA Technical Reports Server (NTRS)

    Alexander, E. C., Jr.

    1971-01-01

    Analysis of lunar soil samples returned by Apollo 11 and 12 flights are discussed. Isotopic studies of the rare gases from Apollo 11 flight lunar samples are presented. The lunar soil analyses indicated the following: (1) high concentrations of solar wind rare gases, (2) isotopic match between solar wind gases and gas components in gas-rich meteorites, and (3) rare gases attributable to spallation reactions induced in heavier nuclides by cosmic ray particles.

  9. Sampling mechanisms for asteroid sample return missions

    NASA Astrophysics Data System (ADS)

    Sears, D.; Franzen, M. A.; Preble, J.; Long, T.

    2003-04-01

    There is a unique challenge in developing sample collectors for low-gravity bodies such as asteroids. Traditional devices rely mostly on gravity for sample collection which is inappropriate in the case of asteroids. The NEAR Shoemaker has shown that we can design spacecrafts that can maneuver very closely to asteroids and provide us with a wealth of valuable data. However, a sample collector that can return samples to the Earth has yet to be fully developed. During the Near-Earth Sample Return Workshop held in Los Angeles in July 2002, the scientific requirements and engineering constraints of sample return collectors were discussed. It was proposed that the touch-and-go-sampler is to be preferred for the first missions. The collector should be as simple as possible, with the minimum of moving parts to reduce cost and prevent damage to the sampler during the collection process as well as minimize surface disturbance on the asteroid. However, the collection procedure must meet certain conditions in order for a complete assessment of the samples. The collection process should not change the composition (molecular, elemental, or isotopic), physical properties, mineral and phase proportions, or grain size distribution. Our answer to these challenges is an adhesive tray collector. The adhesive tray touch-and-go-sampler would include a thirty centimeter in diameter tray bound to a boom. The boom would allow the spacecraft to collect samples with a minimum amount of disturbance from the one to two second encounter with the surface of the asteroid with the adhesive tray. The adhesive tray would be able to sample surface regolith including one to two centimeter clasts in a diverse number of scientifically valuable sites. Once the sample has been collected, the boom will retract and place the adhesive sample tray into a sample return canister. Progress in the development of this collector and preliminary results of testing under microgravity and space conditions will be

  10. Near-Earth Asteroid Sample Return Workshop

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This volume contains abstracts that have been accepted for presentation at the Near-Earth Asteroid Sample Return Workshop, 11-12 Dec 2000. The Steering Committee consisted of Derek Sears, Chair, Dan Britt, Don Brownlee, Andrew Cheng, Benton Clark, Leon Gefert, Steve Gorevan, Marilyn Lindstrom, Carle Pieters, Jeff Preble, Brian Wilcox, and Don Yeomans. Logistical, administrative, and publications support were provided by the Publications and Program Services Department of the Lunar and Planetary Institute.

  11. Horizontal electric fields from lightning return strokes

    NASA Technical Reports Server (NTRS)

    Thomson, E. M.; Medelius, P. J.; Rubinstein, M.; Uman, M. A.; Johnson, J.

    1988-01-01

    An experiment to measure simultaneously the wideband horizontal and vertical electric fields from lightning return strokes is described. Typical wave shapes of the measured horizontal and vertical fields are presented, and the horizontal fields are characterized. The measured horizontal fields are compared with calculated horizontal fields obtained by applying the wavetilt formula to the vertical fields. The limitations and sources of error in the measurement technique are discussed.

  12. Edward Teller Returns to LOS Alamos

    NASA Astrophysics Data System (ADS)

    Hecker, Siegfried S.

    2010-01-01

    I was asked to share some reflections of Edward Teller's return to Los Alamos during my directorship. I met Teller late in his life. My comments focus on that time and they will be mostly in the form of stories of my interactions and those of my colleagues with Teller. Although the focus of this symposium is on Teller's contributions to science, at Los Alamos it was never possible to separate Teller's science from policy and controversy ...

  13. Environmental water incentive policy and return flows

    NASA Astrophysics Data System (ADS)

    Qureshi, M. E.; Schwabe, K.; Connor, J.; Kirby, M.

    2010-04-01

    With increasing urban, industrial, and agricultural water demand and projected reduced supply under climate change, allocations to the environment are critically low in many arid and semiarid basins. Consequently, many governments are striving to augment environmental flows, often through market-oriented mechanisms that involve compensating irrigated agriculture, the largest water user in most basins, for reducing diversions. A widely documented challenge with policies to recover water for the environment arises because part of the water diversion reduction can form the basis for downstream consumptive water rights or environmental flows. This article gives an empirical comparison of two incentive policies to acquire water for environmental flows for a part of the Murray-Darling Basin (MDB), Australia. One policy consists of paying irrigators and water delivery firms to make capital and management investments that improve on-farm irrigation and water-conveyance; the other policy consists of having the government buy water from irrigators on the active MDB water market. The results show that the first option results in relatively larger return flow reduction, while the second option tends to induce significant irrigated land retirement with relatively large reductions in consumptive use and small reductions in return flow. In cases where irrigation losses result in little useful return flow (e.g., evaporative loss reduction or during drought in some instances), efficiency-improving investments may provide some cost-effective opportunities. Where a large portion of loss forms valuable return flow, it is difficult to make a case for the cost-effectiveness of policies involving payments for investments in irrigation and conveyance system upgrades.

  14. Mars Rover/Sample Return landing strategy

    NASA Technical Reports Server (NTRS)

    Friedlander, Alan L.; German, Darla J.

    1988-01-01

    This paper describes the analysis and results of an investigation of the Mars Rover/Sample Return mission's landing strategy, together with the trade-offs of different landing strategies. The percentile points and the descriptive statistics of the probability distribution of traverse distances are calculated using a simple model formulated on the basis of landing error characteristics. The results show that variations in the landing stratgegy can significantly affect the traverse distance requirements, which range from 20 to 200 km.

  15. Mars Sample Return Using Solar Sail Propulsion

    NASA Technical Reports Server (NTRS)

    Johnson, Les; Macdonald, Malcolm; Mcinnes, Colin; Percy, Tom

    2012-01-01

    Many Mars Sample Return (MSR) architecture studies have been conducted over the years. A key element of them is the Earth Return Stage (ERS) whose objective is to obtain the sample from the Mars Ascent Vehicle (MAV) and return it safely to the surface of the Earth. ERS designs predominantly use chemical propulsion [1], incurring a significant launch mass penalty due to the low specific impulse of such systems coupled with the launch mass sensitivity to returned mass. It is proposed to use solar sail propulsion for the ERS, providing a high (effective) specific impulse propulsion system in the final stage of the multi-stage system. By doing so to the launch mass of the orbiter mission can be significantly reduced and hence potentially decreasing mission cost. Further, solar sailing offers a unique set of non-Keplerian low thrust trajectories that may enable modifications to the current approach to designing the Earth Entry Vehicle by potentially reducing the Earth arrival velocity. This modification will further decrease the mass of the orbiter system. Solar sail propulsion uses sunlight to propel vehicles through space by reflecting solar photons from a large, mirror-like surface made of a lightweight, reflective material. The continuous photonic pressure provides propellantless thrust to conduct orbital maneuvering and plane changes more efficiently than conventional chemical propulsion. Because the Sun supplies the necessary propulsive energy, solar sails require no onboard propellant, thus reducing system mass. This technology is currently at TRL 7/8 as demonstrated by the 2010 flight of the Japanese Aerospace Exploration Agency, JAXA, IKAROS mission. [2

  16. Cloud Thickness from Offbeam Returns - Thor Lidar

    NASA Technical Reports Server (NTRS)

    Cahalan, R.; Kolasinski, J.; McGill, M.; Lau, William K. M. (Technical Monitor)

    2002-01-01

    Physical thickness of a cloud layer, and sometimes multiple cloud layers, can be estimated from the time delay of off-beam returns from a pulsed laser source illuminating one side of the cloud layer. In particular, the time delay of light returning from the outer diffuse halo of light surrounding the beam entry point, relative to the time delay at beam center, determines the cloud physical thickness. The delay combined with the pulse stretch gives the optical thickness. The halo method works best for thick cloud layers, typically optical thickness exceeding 2, and thus compliments conventional lidar which cannot penetrate thick clouds. Cloud layer top and base have been measured independently over the ARM/SGP site using conventional laser ranging (lidar) and the top minus base thickness are compared with a cloud top halo estimate obtained from the NASA/Goddard THOR System (THOR = THickness from Offbeam Returns). THOR flies on the NASA P3, and measures the halo timings from several km above cloud top, at the same time providing conventional lidar cloud top height. The ARM/SGP micropulse lidar provides cloud base height for validation.

  17. Allan deviation analysis of financial return series

    NASA Astrophysics Data System (ADS)

    Hernández-Pérez, R.

    2012-05-01

    We perform a scaling analysis for the return series of different financial assets applying the Allan deviation (ADEV), which is used in the time and frequency metrology to characterize quantitatively the stability of frequency standards since it has demonstrated to be a robust quantity to analyze fluctuations of non-stationary time series for different observation intervals. The data used are opening price daily series for assets from different markets during a time span of around ten years. We found that the ADEV results for the return series at short scales resemble those expected for an uncorrelated series, consistent with the efficient market hypothesis. On the other hand, the ADEV results for absolute return series for short scales (first one or two decades) decrease following approximately a scaling relation up to a point that is different for almost each asset, after which the ADEV deviates from scaling, which suggests that the presence of clustering, long-range dependence and non-stationarity signatures in the series drive the results for large observation intervals.

  18. Management of the Returning Traveler with Diarrhea

    PubMed Central

    2009-01-01

    Abstract: Traveler's diarrhea (TD) strikes 20—60% of travelers visiting developing countries. It occurs shortly after the return and can be distinguished into two categories: acute and persistent TD. Acute TD, mostly caused by bacterial and viral pathogens, is usually mild and self-limited, and deserves empirical symptomatic and/or antibiotic therapy in selected cases. Fluoroquinolones are progressively superseded in this indication by azithromycin, a well tolerated macrolide active against most bacteria responsible for TD, including the quinolone-resistant species of Campylobacter jejuni that are now pervasive, especially in Southeast Asia and India. Persistent TD in the returning traveler is much rarer than its acute counterpart and may be associated with three types of causes. Persistent infections, among which Giardia and possibly Entamoeba predominate, account for a significant proportion of cases. Postinfectious processes represent a second cause and comprise temporary lactose malabsorption and postinfectious irritable bowel syndrome, now considered a major cause of persistent TD. Finally, apparently unrelated chronic diseases causing diarrhea are occasionally unmasked by TD and represent a third type of persistent TD, among which the well established case of incident inflammatory bowel disease poses intriguing pathogenesis questions. This review discusses recent advances in the field and provides practical recommendations for the management of TD in adult, immunocompetent returning travelers. PMID:21180583

  19. Barefoot and in a German kitchen: federal parental leave and benefit policy and the return to work after childbirth in Germany.

    PubMed

    Ondrich, J; Spiess, C K; Yang, Q

    1996-01-01

    "Since 1979 German federal maternity leave and benefit policy has given women incentives to stay at home and take care of their newborn and youngest children. In 1986 this leave and benefit policy was changed in several ways, turning it into a powerful instrument for delaying mothers' return to work after childbirth.... We estimate post childbirth return to work hazards for women during the federally protected leave protection period and immediately upon completion of this leave period. During the leave mothers are less likely to return to work the longer is the time left in the leave protection period; however, this result cannot be attributed generally to high levels of maternity benefits. When the leave protection period ends, mothers with strong labor force attachment who are still on leave return to their jobs." PMID:12291882

  20. Implications of deregulation in natural gas industry on utility risks and returns

    NASA Astrophysics Data System (ADS)

    Addepalli, Rajendra P.

    This thesis examines the changes in risk and required return on capital for local distribution utility companies in the increasingly competitive natural gas industry. The deregulation in the industry impacts the LDCs in several ways. First, with the introduction of competition consumers have been given choices among suppliers besides the traditional monopoly, the local utility, for purchasing their natural gas supply needs. Second, with the introduction of competition, some of the interstate pipelines were stuck with 'Take Or Pay' contracts and other costs that resulted in 'stranded costs', which have been passed on to customers of the pipeline including the LDCs. Third, the new obligation for the LDCs to purchase gas from the market, as opposed to buying it from pipelines and passing on the costs to its customers, brought opportunities and risks as well. Finally, with the introduction of competition, in some states LDCs have been allowed to enter into unregulated ventures to increase their profits. In the thesis we first develop a multifactor model (MFM) to explain historical common stock returns of individual utilities and of utility portfolios. We use 'rolling regression' analysis to analyze how different variables explain the variation in stock returns over time. Second, we conduct event studies to analyze the events in the deregulation process that had significant impacts on the LDC returns. Finally we assess the changes in risk and required return on capital for the LDCs over a 15 year time frame, covering the deregulation period. We employ four aspects in the examination of risk and return profile of the utilities: measuring (a) changes in required return on common equity and Weighted Average Cost of Capital, (b) changes in risk premium (WACC less an interest rate proxy), (c) changes in utility bond ratings, and (d) changes in dividend payments, new debt and equity issuances. We perform regression analysis to explain the changes in the required WACC using

  1. Take Me "Home": Return Migration among Germany's Older Immigrants.

    PubMed

    Yahirun, Jenjira J

    2014-08-01

    This paper examines the determinants of return migration as foreign-born men approach old age in Germany. Return migration in later life engages a different set of conditions than return migration earlier on, including the framing of return as a possible retirement strategy. Using 23 years of longitudinal data from the German Socioeconomic Panel, this paper investigates how social and economic resources of immigrant men influence decisions to return "home." Results suggest that immigrants from former guest worker recruitment countries within the European Union are more likely to return than non-E.U. immigrants. In addition, return migrants are "negatively selected" such that those with the least education and weakest attachments to the labor force are more likely to emigrate. However, findings vary greatly depending on the immigrant's age and country of origin. Results from this paper highlight the heterogeneity of older immigrants and the factors that motivate their return "home." PMID:25382866

  2. 78 FR 49296 - Centennial Challenges 2014 Sample Return Robot Challenge

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-13

    ... SPACE ADMINISTRATION Centennial Challenges 2014 Sample Return Robot Challenge AGENCY: National Aeronautics and Space Administration (NASA). ACTION: Notice of Centennial Challenges 2014 Sample Return Robot... Robot Challenge is scheduled and teams that wish to compete may register. Centennial Challenges is...

  3. Period meter for reactors

    DOEpatents

    Rusch, Gordon K.

    1976-01-06

    An improved log N amplifier type nuclear reactor period meter with reduced probability for noise-induced scrams is provided. With the reactor at low power levels a sampling circuit is provided to determine the reactor period by measuring the finite change in the amplitude of the log N amplifier output signal for a predetermined time period, while at high power levels, differentiation of the log N amplifier output signal provides an additional measure of the reactor period.

  4. Lessons Learned from Three Recent Sample Return Missions

    NASA Technical Reports Server (NTRS)

    Zolensky, Michael E.; Sandford, S. A.

    2011-01-01

    We share lessons learned from participation on the Science Teams and Recovery/Preliminary Examination/Curation teams for three recent sample return missions: (1) the Long Duration Exposure Facility (LDEF), which returned to Earth with interplanetary dust and spacecraft debris particles in 1990, (2) the Stardust Mission, which returned grains from comet Wild-2 and fresh interstellar dust to Earth in 2006, and (3) the Hayabusa Mission, which returned regolith grains from asteroid Itokawa in 2010.

  5. The Periodic Pyramid

    ERIC Educational Resources Information Center

    Hennigan, Jennifer N.; Grubbs, W. Tandy

    2013-01-01

    The chemical elements present in the modern periodic table are arranged in terms of atomic numbers and chemical periodicity. Periodicity arises from quantum mechanical limitations on how many electrons can occupy various shells and subshells of an atom. The shell model of the atom predicts that a maximum of 2, 8, 18, and 32 electrons can occupy…

  6. Sample Return Mission to the South Pole Aitken Basin

    NASA Astrophysics Data System (ADS)

    Duke, M. B.; Clark, B. C.; Gamber, T.; Lucey, P. G.; Ryder, G.; Taylor, G. J.

    1999-01-01

    The South Pole Aitken Basin (SPA) is the largest and oldest observed feature on the Moon. Compositional and topographic data from Galileo, Clementine, and Lunar Prospector have demonstrated that SPA represents a distinctive major lunar terrane, which has not been sampled either by sample return missions (Apollo, Luna) or by lunar meteorites. The floor of SPA is characterized by mafic compositions enriched in Fe, Ti, and Th in comparison to its surroundings. This composition may represent melt rocks from the SPA event, which would be mixtures of the preexisting crust and mantle rocks. However, the Fe content is higher than expected, and the large Apollo basin, within SPA, exposes deeper material with lower iron content. Some of the Fe enrichment may represent mare and cryptomare deposits. No model adequately accounts for all of the characteristics of the SPA and disagreements are fundamental. Is mantle material exposed or contained as fragments in melt rock and breccias? If impact melt is present, did the vast sheet differentiate? Was the initial mantle and crust compositionally different from other regions of the Moon? Was the impact event somehow peculiar, (e.g., a low-velocity impact)? The precise time of formation of the SPA is unknown, being limited only by the initial differentiation of the Moon and the age of the Imbrium event, believed to be 3.9 b.y. The questions raised by the SPA can be addressed only with detailed sample analysis. Analysis of the melt rocks, fragments in breccias, and basalts of SPA can address several highly significant problems for the Moon and the history of the solar system. The time of formation of SPA, based on analysis of melt rocks formed in the event. would put limits on the period of intense bombardment of the Moon, which has been inferred by some to include a "terminal cataclysm." If close to 3.9 Ga, the presumed age of the Imbrium Basin, the SPA date would confirm the lunar cataclysm. This episode, if it occurred, would have

  7. The little ice age and medieval warm period in the Sargasso Sea

    SciTech Connect

    Keigwin, L.D.

    1996-11-29

    Sea surface temperature (SST), salinity, and flux of terrigenous material oscillated on millennial time scales in the Pleistocene North Atlantic, but there are few records of Holocene variability. Because of high rates of sediment accumulation, Holocene oscillations are well documented in the northern Sargasso Sea. Results from a radiocarbondated box core show that SST was {approximately} 1{degree}C cooler than today {approximately} 400 years ago (the Little Ice Age) and 1700 years ago, and {approximately} 1{degree}C warmer than today 1000 years ago (the Medieval Warm Period). Thus, at least some of the warming since the Little Ice Age appears to be part of a natural oscillation. 39 refs., 4 figs., 1 tab.

  8. Forecasting volatility in gold returns under the GARCH, IGARCH and FIGARCH frameworks: New evidence

    NASA Astrophysics Data System (ADS)

    Bentes, Sonia R.

    2015-11-01

    This study employs three volatility models of the GARCH family to examine the volatility behavior of gold returns. Much of the literature on this topic suggests that gold plays a fundamental role as a hedge and safe haven against adverse market conditions, which is particularly relevant in periods of high volatility. This makes understanding gold volatility important for a number of theoretical and empirical applications, namely investment valuation, portfolio selection, risk management, monetary policy-making, futures and option pricing, hedging strategies and value-at-risk (VaR) policies (e.g. Baur and Lucey (2010)). We use daily data from August 2, 1976 to February 6, 2015 and divide the full sample into two periods: the in-sample period (August 2, 1976-October 24, 2008) is used to estimate model coefficients, while the out-of-sample period (October 27, 2008-February 6, 2015) is for forecasting purposes. Specifically, we employ the GARCH(1,1), IGARCH(1,1) and FIGARCH(1, d,1) specifications. The results show that the FIGARCH(1, d,1) is the best model to capture linear dependence in the conditional variance of the gold returns as given by the information criteria. It is also found to be the best model to forecast the volatility of gold returns.

  9. Returning Physicians to the Workforce: History, Progress, and Challenges

    ERIC Educational Resources Information Center

    Varjavand, Nielufar; Novack, Dennis H.; Schindler, Barbara A.

    2012-01-01

    There is growing recognition of the need to reeducate clinically inactive physicians seeking to return to practice and in the facilitation of this return. Physicians seeking to return to practice face many challenges: maneuvering the various requirements of licensing, medical, and credentialing boards; finding an appropriate educational program to…

  10. 26 CFR 48.6416(f)-1 - Credit on returns.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 16 2010-04-01 2010-04-01 true Credit on returns. 48.6416(f)-1 Section 48.6416... Special Application to Retailers and Manufacturers Taxes § 48.6416(f)-1 Credit on returns. Any person..., in lieu of claiming refund of the overpayment, claim credit for the overpayment on any return of...

  11. 26 CFR 1.1502-79 - Separate return years.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 12 2010-04-01 2010-04-01 false Separate return years. 1.1502-79 Section 1.1502... (CONTINUED) INCOME TAXES Administrative Provisions and Other Rules § 1.1502-79 Separate return years. (a) Carryover and carryback of consolidated net operating losses to separate return years. For losses arising...

  12. 25 CFR 1200.33 - How can funds be returned?

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 2 2010-04-01 2010-04-01 false How can funds be returned? 1200.33 Section 1200.33... TRUST FUND MANAGEMENT REFORM ACT Returning Tribal Funds to Trust § 1200.33 How can funds be returned....S.C. 162a. Cash can be transferred to the US Treasury by Electronic Funds Transfers (EFT), or...

  13. 26 CFR 55.6071-1 - Time for filing returns.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 17 2010-04-01 2010-04-01 false Time for filing returns. 55.6071-1 Section 55... EXCISE TAXES (CONTINUED) EXCISE TAX ON REAL ESTATE INVESTMENT TRUSTS AND REGULATED INVESTMENT COMPANIES Procedure and Administration § 55.6071-1 Time for filing returns. (a) Returns for calendar years...

  14. 26 CFR 55.6071-1 - Time for filing returns.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 17 2011-04-01 2011-04-01 false Time for filing returns. 55.6071-1 Section 55... EXCISE TAXES (CONTINUED) EXCISE TAX ON REAL ESTATE INVESTMENT TRUSTS AND REGULATED INVESTMENT COMPANIES Procedure and Administration § 55.6071-1 Time for filing returns. (a) Returns for calendar years...

  15. 26 CFR 156.7701-1 - Tax return preparer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 17 2010-04-01 2010-04-01 false Tax return preparer. 156.7701-1 Section 156... EXCISE TAXES (CONTINUED) EXCISE TAX ON GREENMAIL Procedure and Administration § 156.7701-1 Tax return preparer. (a) In general. For the definition of a tax return preparer, see § 301.7701-15 of this...

  16. 26 CFR 54.7701-1 - Tax return preparer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 17 2010-04-01 2010-04-01 false Tax return preparer. 54.7701-1 Section 54.7701... EXCISE TAXES (CONTINUED) PENSION EXCISE TAXES § 54.7701-1 Tax return preparer. (a) In general. For the definition of a tax return preparer, see § 301.7701-15 of this chapter. (b) Effective/applicability...

  17. 26 CFR 53.7701-1 - Tax return preparer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 17 2010-04-01 2010-04-01 false Tax return preparer. 53.7701-1 Section 53.7701... EXCISE TAXES (CONTINUED) FOUNDATION AND SIMILAR EXCISE TAXES Procedure and Administration § 53.7701-1 Tax return preparer. (a) In general. For the definition of a tax return preparer, see § 301.7701-15 of...

  18. 26 CFR 56.7701-1 - Tax return preparer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 17 2010-04-01 2010-04-01 false Tax return preparer. 56.7701-1 Section 56.7701... EXCISE TAXES (CONTINUED) PUBLIC CHARITY EXCISE TAXES § 56.7701-1 Tax return preparer. (a) In general. For the definition of a tax return preparer, see § 301.7701-15 of this chapter. (b)...

  19. 26 CFR 1.6012-6 - Returns by political organizations.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 13 2010-04-01 2010-04-01 false Returns by political organizations. 1.6012-6... TAX (CONTINUED) INCOME TAXES Tax Returns Or Statements § 1.6012-6 Returns by political organizations... political organization described in section 527(e)(1), and every fund described in section 527(f)(3)...

  20. 26 CFR 1.6012-6 - Returns by political organizations.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 13 2014-04-01 2014-04-01 false Returns by political organizations. 1.6012-6... TAX (CONTINUED) INCOME TAXES (CONTINUED) Tax Returns Or Statements § 1.6012-6 Returns by political..., every political organization described in section 527(e)(1), and every fund described in section...