Lagrangian Validation of Numerical Drifter Trajectories Using Drifting Buoys: Application to the Agulhas System

DTIC Science & Technology

2009-05-20

in the meridional overturning circulation of the midlatitude North Atlantic Ocean. J. dim. 21. 6599-6615. Blanke, B., Raynaud. S„ 1997. Kinematics of...Indian to the Atlantic Ocean in the warm upper-branch return flow of the thermohaline circulation (Cordon, 1985). The three numerical data sets...35. L20602. Biastoch, A., Boning. C.W.. Lutjeharms, J.RE., 2008b. Agulhas leakage dynamics affects decadal variability in Atlantic overturning

Crustal structure of the Agulhas Ridge (South Atlantic Ocean): Formation above a hotspot?

NASA Astrophysics Data System (ADS)

Jokat, Wilfried; Hagen, Claudia

2017-10-01

The southern South Atlantic Ocean contains several features believed to document the traces of hotspot volcanism during the early formation of the ocean basin, namely the Agulhas Ridge and the Cape Rise seamounts located in the southeast Atlantic between 36°S and 50°S. The Agulhas Ridge parallels the Agulhas-Falkland Fracture Zone, one of the major transform zones of the world. The morphology of the ridge changes dramatically from two parallel segments in the southwest, to the broad plateau-like Agulhas Ridge in the northeast. Because the crustal fabric of the ridge is unknown relating its evolution to hotspots in the southeast Atlantic is an open question. During the RV Polarstern cruise ANT-XXIII-5 seismic reflection and refraction data were collected along a 370 km long profile with 8 Ocean Bottom Stations to investigate its crustal fabric. The profile extends in NNE direction from the Agulhas Basin, 60 km south of the Agulhas Ridge, and continues into the Cape Basin crossing the southernmost of the Cape Rise seamounts. In the Cape Basin we found a crustal thickness of 5.5-7.5 km, and a velocity distribution typical for oceanic crust. The Cape Rise seamounts, however, show a higher velocity in comparison to the surrounding oceanic crust and the Agulhas Ridge. Underplated material is evident below the southernmost of the Cape Rise seamounts. It also has a 5-8% higher density compared to the Agulhas Plateau. The seismic velocities of the Agulhas Ridge are lower, the crustal thickness is approximately 14 km, and age dating of dredge samples from its top provides clear evidence of rejuvenated volcanism at around 26 Ma. Seismic data indicate that although the Cape Rise seamounts formed above a mantle thermal anomaly it had a limited areal extent, whereas the hotspot material that formed the Agulhas Ridge likely erupted along a fracture zone.

Ocean plankton. Environmental characteristics of Agulhas rings affect interocean plankton transport.

PubMed

Villar, Emilie; Farrant, Gregory K; Follows, Michael; Garczarek, Laurence; Speich, Sabrina; Audic, Stéphane; Bittner, Lucie; Blanke, Bruno; Brum, Jennifer R; Brunet, Christophe; Casotti, Raffaella; Chase, Alison; Dolan, John R; d'Ortenzio, Fabrizio; Gattuso, Jean-Pierre; Grima, Nicolas; Guidi, Lionel; Hill, Christopher N; Jahn, Oliver; Jamet, Jean-Louis; Le Goff, Hervé; Lepoivre, Cyrille; Malviya, Shruti; Pelletier, Eric; Romagnan, Jean-Baptiste; Roux, Simon; Santini, Sébastien; Scalco, Eleonora; Schwenck, Sarah M; Tanaka, Atsuko; Testor, Pierre; Vannier, Thomas; Vincent, Flora; Zingone, Adriana; Dimier, Céline; Picheral, Marc; Searson, Sarah; Kandels-Lewis, Stefanie; Acinas, Silvia G; Bork, Peer; Boss, Emmanuel; de Vargas, Colomban; Gorsky, Gabriel; Ogata, Hiroyuki; Pesant, Stéphane; Sullivan, Matthew B; Sunagawa, Shinichi; Wincker, Patrick; Karsenti, Eric; Bowler, Chris; Not, Fabrice; Hingamp, Pascal; Iudicone, Daniele

2015-05-22

Agulhas rings provide the principal route for ocean waters to circulate from the Indo-Pacific to the Atlantic basin. Their influence on global ocean circulation is well known, but their role in plankton transport is largely unexplored. We show that, although the coarse taxonomic structure of plankton communities is continuous across the Agulhas choke point, South Atlantic plankton diversity is altered compared with Indian Ocean source populations. Modeling and in situ sampling of a young Agulhas ring indicate that strong vertical mixing drives complex nitrogen cycling, shaping community metabolism and biogeochemical signatures as the ring and associated plankton transit westward. The peculiar local environment inside Agulhas rings may provide a selective mechanism contributing to the limited dispersal of Indian Ocean plankton populations into the Atlantic. Copyright © 2015, American Association for the Advancement of Science.

Influences of the Agulhas Current on South African terrestrial climate as inferred from speleothem stable isotope records

NASA Astrophysics Data System (ADS)

Braun, K.; Bar-Matthews, M.; Ayalon, A.; Marean, C.; Herries, A. I. R.; Zahn, R.; Matthews, A.

2012-04-01

South African (SA) climate is strongly influenced by the circulation systems surrounding the subcontinent. The warm tropical Agulhas Current provides large amounts of moisture, transported onshore by south-easterly trade winds during summer. As the trade wind shifts north during winter, the south-western tip of SA is especially affected by temperate westerlies. High amounts of rainfall from the Benguela region off the west coast then only affect the very south-west of the country. This seasonal pattern creates a highly variable terrestrial climate, characterized by strong E-W gradients in the seasonal distribution and amount of rainfall. As summer and winter rain is derived from sources with different properties (density, salinity, temperature), the rainfall also displays seasonal isotopic compositional variations, as for example the present mean δ18O of rainfall in Mossel Bay located in the transition region varies from ~0.13‰ in January to -6.05‰ in July. Vegetation type (C3 vs C4) also follows the rainfall regime with C4 vegetation dominating in the summer rainfall region. As part of the GATEWAYS project, speleothems are used as an excellent, high resolution, precisely dated archive of terrestrial paleoenvironmental conditions[1]. This study focuses on a speleothem record from Crevice Cave on the South African south coast (near Mossel Bay), covering the interval between ~111 and ~53 ka[1,2]. At present, the area is influenced by both summer and winter rainfall, and has mostly C3 type vegetation. Variations in the past show more positive δ18O and δ13C values in the interval corresponding to the glacial MIS 4 and indicate increased summer rainfall and C4 vegetation. This contradicts the common assumption that MIS 4 was characterized by a northward shift of the climatic belts over SA and an increase of winter rainfall and C3 vegetation in the cave area[3]. Comparison of the record to marine sediment cores from the Agulhas Retroflection area[4] and the Cape

Southern ocean winds during past (and future) warm periods and their affect on Agulhas Leakage and the Atlantic Merdional Overturning Circulation

NASA Astrophysics Data System (ADS)

Patel, N. P.; Deconto, R. M.; Condron, A.

2013-12-01

The leakage of Agulhas Current water into the South Atlantic is now thought to be a major player in global climate change. The volume of Agulhas Leakage is linked to the strength and position of southern westerlies. Past changes in the westerly winds over the southern ocean have been noted on glacial-interglacial timescales, in response to both Northern Hemispheric conditions and more proximal changes in Antarctic ice volume. Over recent decades, a southward shift in the southern ocean westerlies has been observed and is expected to continue with projected climate warming. The resulting increase in Agulhas Leakage is thought to allow more warm, salty water from the Indian Ocean into the Atlantic, with the potential to impact the Atlantic Meridional Overturning circulation (AMOC). Some climate models have predicted global warming will result in a slowdown and weakening of the AMOC. A strengthening of the Agulhas Leakage therefore has the potential to counteract that slowdown. Much of the Agulhas leakage is carried in small eddies rotating off the main flow south of Cape Horn. High ocean model resolution (< 1/2°) is therefore required to simulate their response to the overlying wind field. However the majority of previous model studies have been too coarse in resolution to quantify the link between the Agulhas Leakage the AMOC. Here we run a series of global high-resolution ocean model (1/6°) experiments using the MITgcm to test the effect of a shift in the southern hemisphere westerlies on the Agulhas Leakage. A prescribed perturbation of the winds near South Africa shows a significant increase in Agulhas eddies into the Atlantic. Following this, we have conducted longer simulations with the winds over the Southern Ocean perturbed to reflect both past and possible future shifts in the wind field to quantify changes in North Atlantic Deep Water formation and the overall response of the AMOC to this perturbation.

Agulhas Ridge, South Atlantic: the peculiar structure of a transform fault

NASA Astrophysics Data System (ADS)

Uenzelmann-Neben, G.; Gohl, K.

2003-04-01

Transform faults constitute conservative plate boundaries, where adjacent plates are in tangential contact. Transform faults in the ocean are marked by fracture zones, which are long, linear, bathymetric depressions. One of the largest transform offsets on Earth can be found in the South Atlantic. The 1200 km long Agulhas Falkland Fracture Zone (AFFZ), form by this, developed during the Early Cretaceous break-up of West Gondwana. Between approx. 41°S, 16°E and 43°S, 9°E the Agulhas Falkland Fracture Zone is characterised by a pronounced topographic anomaly, the Agulhas Ridge. The Agulhas Ridge rises more than 2 km above the surrounding seafloor. The only equivalent to this kind of topographic high, as part of the AFFZ, is found in form of marginal ridges along the continental parts of the fracture zone, namely the Falkland Escarpment at the South American continent and the Diaz Ridge adjacent to South Africa. But the Agulhas Ridge differs from both the Falkland Escarpment and the Diaz Ridge in the facts (1) that it was not formed during the early rift-drift phase, and (2) that it separates oceanic crust of different age and not continental from oceanic crust. A set of high-resolution seismic reflection data (total length 2000 km) and a seismic refraction line across the Agulhas Ridge give new information on the crustal and basement structure of this tectonic feature. We have observed that within the Cape Basin, to the North, the basement and sedimentary layers are in parts strongly deformed. We observe basement highs, which point towards intrusions. Both the basement and the sedimentary sequence show strong faulting. This points towards a combined tectono-magmatic activity, which led to the formation of basement ridges parallel to the Agulhas Ridge. Since at least the pre-Oligocene parts and, locally, the whole sedimentary column are affected we infer that the renewed activity began in the Middle Oligocene and may have lasted into the Quaternary. As an origin

Return currents in solar flares - Collisionless effects

NASA Technical Reports Server (NTRS)

Rowland, H. L.; Vlahos, L.

1985-01-01

If the primary, precipitating electrons in a solar flare are unstable to beam plasma interactions, it is shown that strong Langmuir turbulence can seriously modify the way in which a return current is carried by the background plasma. In particular, the return (or reverse) current will not be carried by the bulk of the electrons, but by a small number of high velocity electrons. For beam/plasma densities greater than 0.01, this can reduce the effects of collisions on the return current. For higher density beams where the return current could be unstable to current driven instabilities, the effects of strong turbulence anomalous resistivity is shown to prevent the appearance of such instabilities. Again in this regime, how the return current is carried is determined by the beam generated strong turbulence.

Increase in Agulhas leakage due to poleward shift of Southern Hemisphere westerlies.

PubMed

Biastoch, A; Böning, C W; Schwarzkopf, F U; Lutjeharms, J R E

2009-11-26

The transport of warm and salty Indian Ocean waters into the Atlantic Ocean-the Agulhas leakage-has a crucial role in the global oceanic circulation and thus the evolution of future climate. At present these waters provide the main source of heat and salt for the surface branch of the Atlantic meridional overturning circulation (MOC). There is evidence from past glacial-to-interglacial variations in foraminiferal assemblages and model studies that the amount of Agulhas leakage and its corresponding effect on the MOC has been subject to substantial change, potentially linked to latitudinal shifts in the Southern Hemisphere westerlies. A progressive poleward migration of the westerlies has been observed during the past two to three decades and linked to anthropogenic forcing, but because of the sparse observational records it has not been possible to determine whether there has been a concomitant response of Agulhas leakage. Here we present the results of a high-resolution ocean general circulation model to show that the transport of Indian Ocean waters into the South Atlantic via the Agulhas leakage has increased during the past decades in response to the change in wind forcing. The increased leakage has contributed to the observed salinification of South Atlantic thermocline waters. Both model and historic measurements off South America suggest that the additional Indian Ocean waters have begun to invade the North Atlantic, with potential implications for the future evolution of the MOC.

Agulhas leakage as a key process in the modes of Quaternary climate changes

PubMed Central

Caley, Thibaut; Giraudeau, Jacques; Malaizé, Bruno; Rossignol, Linda; Pierre, Catherine

2012-01-01

Heat and salt transfer from the Indian Ocean to the Atlantic Ocean (Agulhas leakage) has an important effect on the global thermohaline circulation and climate. The lack of long transfer record prevents elucidation of its role on climate changes throughout the Quaternary. Here, we present a 1,350-ka accumulation rate record of the planktic foraminiferal species Globorotalia menardii. We demonstrate that, according to previous assumptions, the presence and reseeding of this fauna in the subtropical southeast Atlantic was driven by interocean exchange south of Africa. The Agulhas transfer strengthened at glacial ice-volume maxima for every glacial-interglacial transition, with maximum reinforcements organized according to a 400-ka periodicity. The long-term dynamics of Agulhas leakage may have played a crucial role in regulating meridional overturning circulation and global climate changes during the Mid-Brunhes event and the Mid-Pleistocene transition, and could also play an important role in the near future. PMID:22508999

Agulhas leakage as a key process in the modes of Quaternary climate changes.

PubMed

Caley, Thibaut; Giraudeau, Jacques; Malaizé, Bruno; Rossignol, Linda; Pierre, Catherine

2012-05-01

Heat and salt transfer from the Indian Ocean to the Atlantic Ocean (Agulhas leakage) has an important effect on the global thermohaline circulation and climate. The lack of long transfer record prevents elucidation of its role on climate changes throughout the Quaternary. Here, we present a 1,350-ka accumulation rate record of the planktic foraminiferal species Globorotalia menardii. We demonstrate that, according to previous assumptions, the presence and reseeding of this fauna in the subtropical southeast Atlantic was driven by interocean exchange south of Africa. The Agulhas transfer strengthened at glacial ice-volume maxima for every glacial-interglacial transition, with maximum reinforcements organized according to a 400-ka periodicity. The long-term dynamics of Agulhas leakage may have played a crucial role in regulating meridional overturning circulation and global climate changes during the Mid-Brunhes event and the Mid-Pleistocene transition, and could also play an important role in the near future.

Beam-return current systems in solar flares

NASA Technical Reports Server (NTRS)

Spicer, D. S.; Sudan, R. N.

1984-01-01

It is demonstrated that the common assumption made in solar flare beam transport theory that the beam-accompanied return current is purely electrostatically driven is incorrect, and that the return current is both electrostatically and inductively driven, in accordance with Lenz's law, with the inductive effects dominating for times greater than a few plasma periods. In addition, it is shown that a beam can only exist in a solar plasma for a finite time which is much smaller than the inductive return current dissipation time. The importance of accounting for the role of the acceleration mechanism in forming the beam is discussed. In addition, the role of return current driven anomalous resistivity and its subsequent anomalous Joule heating during the flare process is elucidated.

Does the vorticity flux from Agulhas rings control the zonal pathway of NADW across the South Atlantic?

NASA Astrophysics Data System (ADS)

van Sebille, Erik; Johns, William E.; Beal, Lisa M.

2012-05-01

As part of the global thermohaline circulation, some North Atlantic Deep Water (NADW) exits the Atlantic basin to the south of Africa. Observations have shown that there is a quasi-zonal pathway centered at 25°S carrying NADW eastward, connecting the Deep Western Boundary Current to the Cape Basin. However, it has been unclear what sets this pathway. In particular, waters must move southward through the Cape Basin, thereby crossing isolines of planetary vorticity, in order to exit the basin. Here, we find that an eddy thickness flux induced by Agulhas rings moving northwestward forces a circulation of NADW through the Cape Basin. The pathway at 25°S feeds the southeastward flow of this circulation while conserving potential vorticity. Using Lagrangian floats advected for 300 years in a 1/10° resolution ocean model, we show that the most common pathway for NADW in our model lies directly below the Agulhas ring corridor. By analyzing the velocity and density fields in the model, we find that the decay of these rings, and their forward tilt with depth, results in a southward velocity, across isolines of planetary vorticity, of 1 to 2 cm/s in the deep waters. The associated stream function pattern yields a deep circulation transporting 4 Sv of NADW from the Deep Western Boundary Current at 25°S to the southern tip of Africa.

Lightning Return-Stroke Current Waveforms Aloft, from Measured Field Change, Current, and Channel Geometry

NASA Technical Reports Server (NTRS)

Willett, J. C.; LeVine, D. M.; Idone, V. P.

2006-01-01

Three-dimensional reconstructions of six rocket-triggered lightning channels are derived from stereo photographs. These reconstructed channels are used to infer the behavior of the current in return strokes above the ground from current waveforms measured at the channel base and electric-field-change waveforms measured at a range of 5.2 kilometers for 24 return strokes in these channels. Streak photographs of 14 of the same strokes are analyzed to determine the rise times, propagation speeds, and amplitudes of relative light intensity for comparison with the electrical inferences. Results include the following: 1) The fine structure of the field-change waveforms that were radiated by these subsequent return strokes can be explained, in large part, by channel geometry. 2) The average 10 - 90% rise time of the stroke current increased by about a factor of seven in our sample, from an observed 0.31 plus or minus 0.17 microseconds at the surface to an inferred 2.2 plus or minus 0.5 microcseconds at 1 kilometer path length above the surface. 3) The three-dimensional propagation speed of the current front averaged 1.80 plus or minus 0.24 X 10(exp 8) meters per second over channel lengths typically greater than 1 kilometer. 4) Assuming that the measured current was entirely due to the return stroke forced an unreasonably large and abrupt reduction in inferred current amplitude over the first few tens of meters above the surface, especially in cases when the leader was bright relative to its stroke. Therefore, a significant fraction of the current at the surface was probably due to the leader, at least in such cases. 5) Peak return-stroke currents decreased by approximately 37 plus or minus 12% from 100 meters to 1 kilometer of path length above the surface. Because of uncertainty about how to partition the measured current between leader and return stroke, we are unable to infer the variation of current amplitude near the ground.

Return Stroke Current Reflections in Rocket-Triggered Lightning

NASA Astrophysics Data System (ADS)

Caicedo, J.; Uman, M. A.; Jordan, D.; Biagi, C. J.; Hare, B.

2015-12-01

In the six years from 2009 to 2014, there have been eight triggered flashes at the ICLRT, from a total of 125, in which a total of ten return stroke channel-base currents exhibited a dip 3.0 to 16.6 μs after the initial current peak. Close range electric field measurements show a related dip following the initial electric field peak, and electric field derivative measurements show an associated bipolar pulse, confirming that this phenomenon is not an instrumentation effect in the current measurement. For six of the eight flashes, high-speed video frames show what appears to be suspended sections of unexploded triggering wire at heights of about 150 to 300 m that are illuminated when the upward current wave reaches them. The suspended wire can act as an impedance discontinuity, perhaps as it explodes, and cause a downward reflection of some portion of the upward-propagating current wave. This reflected wave travels down the channel and causes the dip in the measured channel-base current when it reaches ground and reflects upward. The modified transmission line model with exponential decay (MTLE) is used to model the close electric field and electric field derivatives of the postulated initial and reflected current waves, starting with the measured channel base current, and the results are compared favorably with measurements made at distances ranging from 92 to 444 m. From the measured time between current impulse initiation and the time the current reflection reaches the channel base and the current dip initiates, along with the reflection height from the video records, we find the average return stroke current speed for each of the ten strokes to be from 0.28 to 1.9×108 ms-1, with an error of ±0.01×108 ms-1 due to a ±0.1 μs uncertainty in the measurement. This represents the first direct measurement of return stroke current speed, all previous return stroke speed measurements being derived from the luminosity of the process.

A leader-return-stroke consistent macroscopic model for calculations of return stroke current and its optical and electromagnetic emissions

NASA Astrophysics Data System (ADS)

Cai, Shuyao; Chen, Mingli; Du, Yaping; Qin, Zilong

2017-08-01

A downward lightning flash usually starts with a downward leader and an upward connecting leader followed by an upward return stroke. It is the preceding leader that governs the following return stroke property. Besides, the return stroke property evolves with height and time. These two aspects, however, are not well addressed in most existing return stroke models. In this paper, we present a leader-return stroke consistent model based on the time domain electric field integral equation, which is a growth and modification of Kumar's macroscopic model. The model is further extended to simulate the optical and electromagnetic emissions of a return stroke by introducing a set of equations relating the return stroke current and conductance to the optical and electromagnetic emissions. With a presumed leader initiation potential, the model can then simulate the temporal and spatial evolution of the current, charge transfer, channel size, and conductance of the return stroke, furthermore the optical and electromagnetic emissions. The model is tested with different leader initiation potentials ranging from -10 to -140 MV, resulting in different return stroke current peaks ranging from 2.6 to 209 kA with different return stroke speed peaks ranging from 0.2 to 0.8 speed of light and different optical power peaks ranging from 4.76 to 248 MW/m. The larger of the leader initiation potential, the larger of the return stroke current and speed. Both the return stroke current and speed attenuate exponentially as it propagates upward. All these results are qualitatively consistent with those reported in the literature.

Uncovering a New Current: The Southwest MAdagascar Coastal Current

NASA Astrophysics Data System (ADS)

Ramanantsoa, Juliano D.; Penven, P.; Krug, M.; Gula, J.; Rouault, M.

2018-02-01

Cruise data sets, satellite remote sensing observations, and model data analyses are combined to highlight the existence of a coastal surface poleward flow in the southwest of Madagascar: the Southwest MAdagascar Coastal Current (SMACC). The SMACC is a relatively shallow (<300 m) and narrow (<100 km wide) warm and salty coastal surface current, which flows along the south western coast of Madagascar toward the south, opposite to the dominant winds. The warm water surface signature of the SMACC extends from 22°S (upstream) to 26.4°S (downstream). The SMACC exhibits a seasonal variability: more intense in summer and reduced in winter. The average volume transport of its core is about 1.3 Sv with a mean summer maximum of 2.1 Sv. It is forced by a strong cyclonic wind stress curl associated with the bending of the trade winds along the southern tip of Madagascar. The SMACC directly influences the coastal upwelling regions south of Madagascar. Its existence is likely to influence local fisheries and larval transport patterns, as well as the connectivity with the Agulhas Current, affecting the returning branch of the global overturning circulation.

Changing surface water conditions for the last 500 ka in the Southeast Atlantic: Implications for variable influences of Agulhas leakage and Benguela upwelling

NASA Astrophysics Data System (ADS)

Petrick, Benjamin F.; McClymont, Erin L.; Marret, Fabienne; van der Meer, Marcel T. J.

2015-09-01

The Southeast Atlantic Ocean is an important component of global ocean circulation, as it includes heat and salt transfer into the Atlantic through the Agulhas leakage as well as the highly productive Benguela upwelling system. Here we reconstruct sea surface temperatures (SSTs) from Ocean Drilling Program (ODP) Site 1087 in the Southeast Atlantic to investigate surface ocean circulation patterns during the late Pleistocene (0-500 ka). The UK'37 index and dinoflagellate cyst assemblages are used to reconstruct SSTs, δDalkenone is used to reconstruct changes in sea surface salinity, and mass accumulation rates of alkenones and chlorine pigments are quantified to detect changing marine export productivity. The greatest amplitude of SST warming precedes decreases in benthic δ18O and therefore occurs early in the transition from glacials to interglacials. The δDalkenone, as a salinity indicator, increases before SSTs, suggesting that the pattern of Agulhas leakage is more complex than suggested by SST proxies. Marine isotope stage (MIS) 10 shows an anomalous pattern: it is marked by a pronounced increase in chlorine concentration, which may be related to enhanced/expanded Benguela upwelling reaching the core site. We find no evidence of an absence of Agulhas leakage throughout the record, suggesting that there is no Agulhas cutoff even during MIS 10. Finally, the ODP Site 1087 record shows an increasing strength of Agulhas leakage towards the present day, which may have impacted the intensity of the Atlantic meridional overturning circulation. As a result, the new analyses from ODP Site 1087 demonstrate a complex interaction between influences of the Benguela upwelling and the Agulhas leakage through the late Pleistocene, which are inferred here to reflect changing circulation patterns in the Southern Ocean and in the atmosphere.

Return stroke velocities and currents using a solid state silicon detector system

NASA Technical Reports Server (NTRS)

Mach, Douglas M.; Rust, W. David

1988-01-01

A small, portable device has been developed to measure return stroke velocities. With the device, velocities from 135 strokes that consist of 92 natural return strokes and 43 triggered return strokes have been analyzed. The average return stroke velocity for longer channels, greater than 500 meters, is 1.2 + or - 0.3 x 10 to the 8th m/s for both natural and triggered return strokes. For shorter channel lengths, less than 500 m, natural lightning has a statistically higher average return stroke velocity of 1.9 + or - 0.7 x 10 to the 8th m/s than triggered lightning with an average return stroke velocity of 1.4 + or - 0.4 x 10 to the 8th m/s. Using the transmission line model of the return stroke, natural lightning has a peak current distribution that is log-normal with a median value of 19 kA. Return stroke velocities and currents were determined for two distant single stroke natural positive cloud-to-ground flashes. The velocities were 1.0 and 1.7 x 10 to the 8th ms/s while the estimated peak current for each positive flash was over 125 kA.

Changing surface water conditions for the last 500 ka in the Southeast Atlantic:Tracking Agulhas leakage using UK37' and δD

NASA Astrophysics Data System (ADS)

Petrick, Benjamin; McClymont, Erin; van der Meer, Marcel; Marret, Fabienne

2015-04-01

The Southeast Atlantic Ocean is an important component of global ocean circulation, as it includes heat and salt transfer into the Atlantic through Agulhas Leakage. Here, we reconstruct sea surface temperatures (SSTs) and sea surface salinity from Ocean Drilling Program (ODP) Site 1087 in the Southeast Atlantic to investigate surface ocean circulation patterns during the late Pleistocene (0-500 ka). The alkenone-derived U37K'index and assemblages of dinoflagellate cysts are used to reconstruct SSTs. The hydrogen isotope composition of the alkenones (δDalkenone) is used to reconstruct changes in sea-surface salinity. The greatest amplitude of SST warming precedes decreases in benthic δ18O and therefore occurs early in the transition from glacials to interglacials. The timing of the early warming is consistent with previously published foraminifera reconstructions from the same site (Caley et al., 2012). However, δDalkenone decreases at the start of interglacials, suggesting that sea surface salinity increased earlier than the deglacial warmings, and indicating that the pattern of Agulhas leakage is more complex than suggested by SST proxies alone. Furthermore, the δDalkenonevalues indicate a strong salinity increases occurred before both MIS 11 and MIS 1, which are both periods where there is evidence of connection between increased Agulhas Leakage and a stronger Atlantic meridional overturning circulation (AMOC). Finally, the ODP site 1087 record shows an overall trend of increasing SSTs and δDalkenone towards the present day, suggesting that Agulhas leakage has strengthened since 500 ka, which may have impacted the intensity of the AMOC. Caley, T., Giraudeau, J., Malaize, B., Rossignol, L., Pierre, C., 2012. Agulhas leakage as a key process in the modes of Quaternary climate changes. Proc. Natl. Acad. Sci. 109, 6835-6839. doi:10.1073/pnas.1115545109

South Atlantic circulation in a world ocean model

NASA Astrophysics Data System (ADS)

England, Matthew H.; Garçon, Véronique C.

1994-09-01

The circulation in the South Atlantic Ocean has been simulated within a global ocean general circulation model. Preliminary analysis of the modelled ocean circulation in the region indicates a rather close agreement of the simulated upper ocean flows with conventional notions of the large-scale geostrophic currents in the region. The modelled South Atlantic Ocean witnesses the return flow and export of North Atlantic Deep Water (NADW) at its northern boundary, the inflow of a rather barotropic Antarctic Circumpolar Current (ACC) through the Drake Passage, and the inflow of warm saline Agulhas water around the Cape of Good Hope. The Agulhas leakage amounts to 8.7 Sv, within recent estimates of the mass transport shed westward at the Agulhas retroflection. Topographic steering of the ACC dominates the structure of flow in the circumpolar ocean. The Benguela Current is seen to be fed by a mixture of saline Indian Ocean water (originating from the Agulhas Current) and fresher Subantarctic surface water (originating in the ACC). The Benguela Current is seen to modify its flow and fate with depth; near the surface it flows north-westwards bifurcating most of its transport northward into the North Atlantic Ocean (for ultimate replacement of North Atlantic surface waters lost to the NADW conveyor). Deeper in the water column, more of the Benguela Current is destined to return with the Brazil Current, though northward flows are still generated where the Benguela Current extension encounters the coast of South America. At intermediate levels, these northward currents trace the flow of Antarctic Intermediate Water (AAIW) equatorward, though even more AAIW is seen to recirculate poleward in the subtropical gyre. In spite of the model's rather coarse resolution, some subtle features of the Brazil-Malvinas Confluence are simulated rather well, including the latitude at which the two currents meet. Conceptual diagrams of the recirculation and interocean exchange of thermocline

Lateral eddy diffusivity estimates from simulated and observed drifter trajectories: a case study for the Agulhas Current system

NASA Astrophysics Data System (ADS)

Rühs, Siren; Zhurbas, Victor; Durgadoo, Jonathan V.; Biastoch, Arne

2017-04-01

The Lagrangian description of fluid motion by sets of individual particle trajectories is extensively used to characterize connectivity between distinct oceanic locations. One important factor influencing the connectivity is the average rate of particle dispersal, generally quantified as Lagrangian diffusivity. In addition to Lagrangian observing programs, Lagrangian analyses are performed by advecting particles with the simulated flow field of ocean general circulation models (OGCMs). However, depending on the spatio-temporal model resolution, not all scale-dependent processes are explicitly resolved in the simulated velocity fields. Consequently, the dispersal of advective Lagrangian trajectories has been assumed not to be sufficiently diffusive compared to observed particle spreading. In this study we present a detailed analysis of the spatially variable lateral eddy diffusivity characteristics of advective drifter trajectories simulated with realistically forced OGCMs and compare them with estimates based on observed drifter trajectories. The extended Agulhas Current system around South Africa, known for its intricate mesoscale dynamics, serves as a test case. We show that a state-of-the-art eddy-resolving OGCM indeed features theoretically derived dispersion characteristics for diffusive regimes and realistically represents Lagrangian eddy diffusivity characteristics obtained from observed surface drifter trajectories. The estimates for the maximum and asymptotic lateral single-particle eddy diffusivities obtained from the observed and simulated drifter trajectories show a good agreement in their spatial pattern and magnitude. We further assess the sensitivity of the simulated lateral eddy diffusivity estimates to the temporal and lateral OGCM output resolution and examine the impact of the different eddy diffusivity characteristics on the Lagrangian connectivity between the Indian Ocean and the South Atlantic.

Photoelectric return-stroke velocity and peak current estimates in natural and triggered lightning

NASA Technical Reports Server (NTRS)

Mach, Douglas M.; Rust, W. David

1989-01-01

Two-dimensional photoelectric return stroke velocities from 130 strokes are presented, including 86 negative natural, 41 negative triggered, one positive triggered, and two positive natural return strokes. For strokes starting near the ground and exceeding 500 m in length, the average velocity is 1.3 + or - 0.3 X 10 to the 8th m/s for natural return strokes and 1.2 + or - 0.3 X 10 to the 8th m/s for triggered return strokes. For strokes with lengths less than 500 m, the average velocities are slightly higher. Using the transmission line model (TLM), the shortest segment one-dimensional return stroke velocity, and either the maximum or plateau electric field, it is shown that natural strokes have a peak current distribution that is lognormal with a median value of 16 kA (maximum E) or 12 kA (plateau E). Triggered lightning has a medium peak current value of 21 kA (maximum E) or 15 kA (plateau E). Correlations are found between TLM peak currents and velocities for triggered and natural subsequent return strokes, but not between TLM peak currents and natural first return stroke velocities.

Bulk Current Injection Testing of Close Proximity Cable Current Return, 1kHz to 1 MHz

NASA Technical Reports Server (NTRS)

Bradley, Arthur T.; Lee, William M.; Singh, Vivek; Yavoich, Brian

2010-01-01

This paper presents the results of an experiment examining the percentage of current that returns on adjacent wires or through a surrounding cable shield rather than through a shared conducting chassis. Simulation and measurement data are compared from 1 kHz 1 MHz for seven common cable configurations. The phenomenon is important to understand, because minimizing the return current path is vital in developing systems with low radiated emissions.

Ocean-Atmosphere Interaction Over Agulhas Extension Meanders

NASA Technical Reports Server (NTRS)

Liu, W. Timothy; Xie, Xiaosu; Niiler, Pearn P.

2007-01-01

Many years of high-resolution measurements by a number of space-based sensors and from Lagrangian drifters became available recently and are used to examine the persistent atmospheric imprints of the semi-permanent meanders of the Agulhas Extension Current (AEC), where strong surface current and temperature gradients are found. The sea surface temperature (SST) measured by the Advanced Microwave Scanning Radiometer-Earth Observing System (AMSR-E) and the chlorophyll concentration measured by the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) support the identification of the meanders and related ocean circulation by the drifters. The collocation of high and low magnitudes of equivalent neutral wind (ENW) measured by Quick Scatterometer (QuikSCAT), which is uniquely related to surface stress by definition, illustrates not only the stability dependence of turbulent mixing but also the unique stress measuring capability of the scatterometer. The observed rotation of ENW in opposition to the rotation of the surface current clearly demonstrates that the scatterometer measures stress rather than winds. The clear differences between the distributions of wind and stress and the possible inadequacy of turbulent parameterization affirm the need of surface stress vector measurements, which were not available before the scatterometers. The opposite sign of the stress vorticity to current vorticity implies that the atmosphere spins down the current rotation through momentum transport. Coincident high SST and ENW over the southern extension of the meander enhance evaporation and latent heat flux, which cools the ocean. The atmosphere is found to provide negative feedback to ocean current and temperature gradients. Distribution of ENW convergence implies ascending motion on the downwind side of local SST maxima and descending air on the upwind side and acceleration of surface wind stress over warm water (deceleration over cool water); the convection may escalate the contrast of

Collisionless effects on beam-return current systems in solar flares

NASA Technical Reports Server (NTRS)

Vlahos, L.; Rowland, H. L.

1985-01-01

A theoretical study of the beam-return current system (BRCS) in solar flares shows that the precipitating electrons modify the way in which the return current (RC) is carried by the background plasma. In particular it is found that the RC is not carried by the bulk of the electrons but by a small number of high-velocity electrons. For beam/plasma densities exceeding approximately 0.001, this can reduce the effects of collisions and heating by the RC. For higher-density beams, where the RC could be unstable to current-driven instabilities, the effects of strong turbulence anomalous resistivity prevent the appearance of such instabilities. The main conclusion is that the BRCS is interconnected, and that the beam-generated strong turbulence determines how the RC is carried.

On the behavior of return stroke current and the remotely detected electric field change waveform

NASA Astrophysics Data System (ADS)

Shao, Xuan-Min; Lay, Erin; Jacobson, Abram R.

2012-04-01

After accumulating a large number of remotely recorded negative return stroke electric field change waveforms, a subtle but persistent kink was found following the main return stroke peak by several microseconds. To understand the corresponding return stroke current properties behind the kink and the general return stroke radiation waveform, we analyze strokes occurring in triggered lightning flashes for which have been measured both the channel base current and simultaneous remote electric radiation field. In this study, the channel base current is assumed to propagate along the return stroke channel in a dispersive and lossy manner. The measured channel base current is band-pass filtered, and the higher-frequency component is assumed to attenuate faster than the lower-frequency component. The radiation electric field is computed for such a current behavior and is then propagated to distant sensors. It is found that such a return stroke model is capable of very closely reproducing the measured electric waveforms at multiple stations for the triggered return strokes, and such a model is considered applicable to the common behavior of the natural return stroke as well. On the basis of the analysis, a number of other observables are derived. The time-evolving current dispersion and attenuation compare well with previously reported optical observations. The observable speed tends to agree with optical and VHF observations. Line charge density that is removed or deposited by the return stroke is derived, and the implication of the charge density distribution on leader channel decay is discussed.

Understanding Breaks in Flare X-Ray Spectra: Evaluation of a Cospatial Collisional Return-current Model

NASA Astrophysics Data System (ADS)

Alaoui, Meriem; Holman, Gordon D.

2017-12-01

Hard X-ray (HXR) spectral breaks are explained in terms of a one-dimensional model with a cospatial return current. We study 19 flares observed by the Ramaty High Energy Solar Spectroscopic Imager with strong spectral breaks at energies around a few deka-keV, which cannot be explained by isotropic albedo or non-uniform ionization alone. We identify these breaks at the HXR peak time, but we obtain 8 s cadence spectra of the entire impulsive phase. Electrons with an initially power-law distribution and a sharp low-energy cutoff lose energy through return-current losses until they reach the thick target, where they lose their remaining energy through collisions. Our main results are as follows. (1) The return-current collisional thick-target model provides acceptable fits for spectra with strong breaks. (2) Limits on the plasma resistivity are derived from the fitted potential drop and deduced electron-beam flux density, assuming the return current is a drift current in the ambient plasma. These resistivities are typically 2–3 orders of magnitude higher than the Spitzer resistivity at the fitted temperature, and provide a test for the adequacy of classical resistivity and the stability of the return current. (3) Using the upper limit of the low-energy cutoff, the return current is always stable to the generation of ion-acoustic and electrostatic ion-cyclotron instabilities when the electron temperature is nine times lower than the ion temperature. (4) In most cases, the return current is most likely primarily carried by runaway electrons from the tail of the thermal distribution rather than by the bulk drifting thermal electrons. For these cases, anomalous resistivity is not required.

Assessment of Hybrid Coordinate Model Velocity Fields During Agulhas Return Current 2012 Cruise

DTIC Science & Technology

2013-06-01

Forecasts GDEM Generalized Digital Environmental Model GPS Global Positioning System HYCOM HYbrid Coordinate Ocean Model MICOM Miami Isopycnal...speed profiles was climatology from the Generalized Digital Environmental Model ( GDEM ; Teague et al. 1990). Made operational in 1999, the Modular... GDEM was the only tool a naval oceanographer had at his or her disposal to characterize ocean conditions where in-situ observations could not be

Submicrosecond characteristics of lightning return-stroke currents

NASA Technical Reports Server (NTRS)

Leteinturier, Christiane; Hamelin, Joel H.; Eybert-Berard, Andre

1991-01-01

The authors describe the experimental results obtained during 1987 and 1988 triggered-lightning experiments in Florida. Seventy-four simultaneous submicrosecond time-resolved measurements of triggered return-stroke current (I) and current derivative (dI/dt) were made in Florida in 1987 and 1988. Peak currents ranged from about 5 to 76 kA, peak dI/dt amplitude from 13 to 411 kA/microsec and rise time from 90 to 1000 ns. The mean peak dI/dt values of 110 kA/microsec were 2-3 times higher than data from instrumented towers and peak I and dI/dt appear to be positively correlated. These data confirm previous experiments and conclusions supported by forty measurements. They are important in order to define, for example, standards for lightning protection. Present standards give a dI/dt maximum of 140 kA/microsec.

Ocean Virtual Laboratory: A New Way to Explore Multi-Sensor Synergy Demonstrated over the Agulhas Region

NASA Astrophysics Data System (ADS)

Collard, F.; Quartly, G. D.; Konik, M.; Johannessen, J. A.; Korosov, A.; Chapron, B.; Piolle, J.-F.; Herledan, S.; Darecki, M.; Isar, A.; Nafornita, C.

2015-12-01

Ocean Virtual Laboratory is an ESA-funded project to prototype the concept of a single point of access for all satellite remote-sensing data with ancillary model output and in situ measurements for a given region. The idea is to provide easy access for the non-specialist to both data and state-of-the-art processing techniques and enable their easy analysis and display. The project, led by OceanDataLab, is being trialled in the region of the Agulhas Current, as it contains signals of strong contrast (due to very energetic upper ocean dynamics) and special SAR data acquisitions have been recorded there. The project also encourages the take up of Earth Observation data by developing training material to help those not in large scientific or governmental organizations make the best use of what data are available. The website for access is: http://ovlproject.oceandatalab.com/

The evolution of discharge current and channel radius in cloud-to-ground lightning return stroke process

NASA Astrophysics Data System (ADS)

Fan, Tingting; Yuan, Ping; Wang, Xuejuan; Cen, Jianyong; Chang, Xuan; Zhao, Yanyan

2017-09-01

The spectra of two negative cloud-to-ground lightning discharge processes with multi-return strokes are obtained by a slit-less high-speed spectrograph, which the temporal resolution is 110 μs. Combined with the synchronous electrical observation data and theoretical calculation, the physical characteristics during return strokes process are analysed. A positive correlation between discharge current and intensity of ionic lines in the spectra is verified, and based on this feature, the current evolution characteristics during four return strokes are investigated. The results show that the time from peak current to the half-peak value estimated by multi point-fitting is about 101 μs-139 μs. The Joule heat in per unit length of four return strokes channel is in the order of 105J/m-106 J/m. The radius of arc discharge channel is positively related to the discharge current, and the more intense the current is, the greater the radius of channel is. Furthermore, the evolution for radius of arc core channel in the process of return stroke is consistent with the change trend of discharge current after the peak value. Compared with the decay of the current, the temperature decreases more slowly.

Uplift history of a transform continental margin revealed by the stratigraphic record: The case of the Agulhas transform margin along the Southern African Plateau

NASA Astrophysics Data System (ADS)

Baby, Guillaume; Guillocheau, François; Boulogne, Carl; Robin, Cécile; Dall'Asta, Massimo

2018-04-01

The south and southeast coast of southern Africa (from 28°S to 33°S) forms a high-elevated transform passive margin bounded to the east by the Agulhas-Falkland Fracture Zone (AFFZ). We analysed the stratigraphic record of the Outeniqua and Durban (Thekwini) Basins, located on the African side of the AFFZ, to determine the evolution of these margins from the rifting stage to present-day. The goal was to reconstruct the strike-slip evolution of the Agulhas Margin and the uplift of the inland high-elevation South African Plateau. The Agulhas transform passive margin results from four successive stages: Rifting stage, from Late Triassic to Early Cretaceous ( 200?-134 Ma), punctuated by three successive rifting episodes related to the Gondwana breakup; Wrench stage (134-131 Ma), evidenced by strike- and dip-slip deformations increasing toward the AFFZ; Active transform margin stage (131-92 Ma), during which the Falkland/Malvinas Plateau drifts away along the AFFZ, with an uplift of the northeastern part of the Outeniqua Basin progressively migrating toward the west; Thermal subsidence stage (92-0 Ma), marked by a major change in the configuration of the margin (onset of the shelf-break passive margin morphology). Two main periods of uplift were documented during the thermal subsidence stage of the Agulhas Margin: (1) a 92 Ma short-lived margin-scale uplift, followed by a second one at 76 Ma located along the Outeniqua Basin and; (2) a long-lasting uplift from 40 to 15 Ma limited to the Durban (Thekwini) Basin. This suggests that the South African Plateau is an old Upper Cretaceous relief (90-70 Ma) reactivated during Late Eocene to Early Miocene times (40-15 Ma).

Lightning Return-Stroke Current Waveforms Aloft, From Measured Field Change, Current, and Channel Geometry

NASA Technical Reports Server (NTRS)

Willett, J. C.; LeVine, D. M.

2002-01-01

Direct current measurements are available near the attachment point from both natural cloud-to-ground lightning and rocket-triggered lightning, but little is known about the rise time and peak amplitude of return-stroke currents aloft. We present, as functions of height, current amplitudes, rise times, and effective propagation velocities that have been estimated with a novel remote-sensing technique from data on 24 subsequent return strokes in six different lightning flashes that were triggering at the NASA Kennedy Space Center, FL, during 1987. The unique feature of this data set is the stereo pairs of still photographs, from which three-dimensional channel geometries were determined previously. This has permitted us to calculate the fine structure of the electric-field-change (E) waveforms produced by these strokes, using the current waveforms measured at the channel base together with physically reasonable assumptions about the current distributions aloft. The computed waveforms have been compared with observed E waveforms from the same strokes, and our assumptions have been adjusted to maximize agreement. In spite of the non-uniqueness of solutions derived by this technique, several conclusions seem inescapable: 1) The effective propagation speed of the current up the channel is usually significantly (but not unreasonably) faster than the two-dimensional velocity measured by a streak camera for 14 of these strokes. 2) Given the deduced propagation speed, the peak amplitude of the current waveform often must decrease dramatically with height to prevent the electric field from being over-predicted. 3) The rise time of the current wave front must always increase rapidly with height in order to keep the fine structure of the calculated field consistent with the observations.

Biogeochemical and ecological impacts of boundary currents in the Indian Ocean

NASA Astrophysics Data System (ADS)

Hood, Raleigh R.; Beckley, Lynnath E.; Wiggert, Jerry D.

2017-08-01

, though local wind forcing can lead to transient near shore current reversals and localized coastal upwelling. The poleward direction of this eastern boundary current is unique. Due to its high kinetic energy the Leeuwin Current sheds anomalous, relatively high chlorophyll, warm-core, downwelling eddies that transport coastal diatom communities westward into open ocean waters. Variations in the Leeuwin transport and eddy generation impact many higher trophic level species including the recruitment and fate of rock lobster (Panulirus cygnus) larvae. In contrast, the transport of the Agulhas Current is very large, with sources derived from the Mozambique Channel, the East Madagascar Current and the southwest Indian Ocean sub-gyre. Dynamically, the Agulhas Current is upwelling favorable; however, the spatial distribution of prominent surface manifestations of upwelling is controlled by local wind and topographic forcing. Meanders and eddies in the Agulhas Current propagate alongshore and interact with seasonal changes in the winds and topographic features. These give rise to seasonally variable localized upwelling and downwelling circulations with commensurate changes in primary production and higher trophic level responses. Due to the strong influence of the Agulhas Current, many neritic fish species in southeast Africa coastal waters have evolved highly selective behaviors and reproductive patterns for successful retention of planktonic eggs and larvae. For example, part of the Southern African sardine (Sardinops sagax) stock undergoes a remarkable northward migration enhanced by transient cyclonic eddies in the shoreward boundary of the Agulhas Current. There is evidence from the paleoceanographic record that these currents and their biogeochemical and ecological impacts have changed significantly over glacial to interglacial timescales. These changes are explored as a means of providing insight into the potential impacts of climate change in the Indian Ocean.

Identifying Return-Current Losses in Flare Hard X-ray Spectra

NASA Technical Reports Server (NTRS)

Holman, Gordon D.

2011-01-01

I will report on theoretical studies and a data analysis program aimed at identifying and physically interpreting breaks in hard X-ray spectra resulting from return-current energy losses, as well as heating of the flare plasma resulting from these losses.

Effects of midlatitude westerlies on the paleoproductivity at the Agulhas Bank slope during the penultimate glacial cycle: Evidence from coccolith Sr/Ca ratios

NASA Astrophysics Data System (ADS)

Mejia, Luz Maria; Ziveri, Patrizia; Cagnetti, Marilisa; Bolton, Clara; Zahn, Rainer; Marino, Gianluca; Martinez Mendez, Gema; Stoll, Heather

2015-04-01

Because modern primary productivity on the Agulhas Bank, off South Africa, is linked to the mid-latitude westerlies, a paleoproductivity record from this area could be used to investigate past may changes in the westerlies dynamics. Coccolith Sr/Ca is a suitable productivity indicator to explore paleoproductivity from the penultimate glacial-interglacial cycle because it is independent of preservation changes that may accompany changes in deepwater circulation. In the Agulhas Bank slope core MD96-2080, the coccolith Sr/Ca record shows that phases of depressed productivity coincided with periods of stratification in the same core, indicated by high relative abundances of the coccolithophore Florisphaera profunda, and with low relative abundances of the upwelling indicator G. bulloides in the Cape Basin. This coherence suggests that upwelling regulated productivity throughout this region. As in the present, we infer that periods of low productivity result from northward positions of the westerlies which block the upwelling-promoting easterlies. Productivity minima also coincide with periods of increased ice-rafted detritus (IRD) deposition on the Agulhas Plateau, which also indicates extreme northward positions of the westerlies. The influence of the westerlies appears to be obliquity-conditioned, as productivity minima occur during low obliquity intervals. The dynamic connection between productivity and the westerlies is supported by coeval salinity changes in the South Indian Gyre that likewise respond sensitively to a poleward contraction of the westerlies.

Understanding the Impact of Return-Current Losses on the X-Ray Emission from Solar Flares

NASA Technical Reports Server (NTRS)

Holman, Gordon D.

2012-01-01

I obtain and examine the implications of one-dimensional analytic solutions for return-current losses on an initially power-law distribution of energetic electrons with a sharp low-energy cutoff in flare plasma with classical (collisional) resistivity. These solutions show, for example, that return-current losses are not sensitive to plasma density, but are sensitive to plasma temperature and the low energy cutoff of the injected nonthermal electron distribution. A characteristic distance from the electron injection site, x(sub rc), is derived. At distances less than x(sub rc) the electron flux density is not reduced by return-current losses, but plasma heating can be substantial in this region, in the upper, coronal part of the flare loop. Before the electrons reach the collisional thick-target region of the flare loop, an injected power-law electron distribution with a low-energy cutoff maintains that structure, but with a flat energy distribution below the cutoff energy, which is now determined by the total potential drop experienced by the electrons. Modifications due to the presence of collisional losses are discussed. I compare these results with earlier analytical results and with more recent numerical simulations. Emslie's 1980 conjecture that there is a maximum integrated X-ray source brightness on the order of 10(exp -15) photons per square centimeter per second per square centimeter is examined. I find that this is not actually a maximum brightness and its value is parameter dependent, but it is nevertheless a valuable benchmark for identifying return-current losses in hard X-ray spectra. I discuss an observational approach to identifying return-current losses in flare data, including identification of a return-current "bump" in X-ray light curves at low photon energies.

Advanced Curation: Solving Current and Future Sample Return Problems

NASA Technical Reports Server (NTRS)

Fries, M.; Calaway, M.; Evans, C.; McCubbin, F.

2015-01-01

Advanced Curation is a wide-ranging and comprehensive research and development effort at NASA Johnson Space Center that identifies and remediates sample related issues. For current collections, Advanced Curation investigates new cleaning, verification, and analytical techniques to assess their suitability for improving curation processes. Specific needs are also assessed for future sample return missions. For each need, a written plan is drawn up to achieve the requirement. The plan draws while upon current Curation practices, input from Curators, the analytical expertise of the Astromaterials Research and Exploration Science (ARES) team, and suitable standards maintained by ISO, IEST, NIST and other institutions. Additionally, new technologies are adopted on the bases of need and availability. Implementation plans are tested using customized trial programs with statistically robust courses of measurement, and are iterated if necessary until an implementable protocol is established. Upcoming and potential NASA missions such as OSIRIS-REx, the Asteroid Retrieval Mission (ARM), sample return missions in the New Frontiers program, and Mars sample return (MSR) all feature new difficulties and specialized sample handling requirements. The Mars 2020 mission in particular poses a suite of challenges since the mission will cache martian samples for possible return to Earth. In anticipation of future MSR, the following problems are among those under investigation: What is the most efficient means to achieve the less than 1.0 ng/sq cm total organic carbon (TOC) cleanliness required for all sample handling hardware? How do we maintain and verify cleanliness at this level? The Mars 2020 Organic Contamination Panel (OCP) predicts that organic carbon, if present, will be present at the "one to tens" of ppb level in martian near-surface samples. The same samples will likely contain wt% perchlorate salts, or approximately 1,000,000x as much perchlorate oxidizer as organic carbon

Theoretical study of the effect of ionospheric return currents on the electron temperature

NASA Technical Reports Server (NTRS)

Schunk, R. W.; Sojka, J. J.; Bowline, M. D.

1987-01-01

A time-dependent, three-dimensional model of the high-altitude ionosphere is presently used to study the effects of field-aligned ionospheric return currents on auroral electron temperatures for different seasonal and solar cycle conditions, as well as for different upper boundary heat fluxes. The average, large scale, return current densities, which are a few microamps/sq m, are too small to affect auroral electron temperatures. The thermoelectric effect exhibits a pronounced solar cycle and seasonal dependence, and its heat transport corresponds to an upward flow of electron energy which can be either a source or sink of electron energy depending on altitude and geophysical conditions.

Correlated peak relative light intensity and peak current in triggered lightning subsequent return strokes

NASA Technical Reports Server (NTRS)

Idone, V. P.; Orville, R. E.

1985-01-01

The correlation between peak relative light intensity L(R) and stroke peak current I(R) is examined for 39 subsequent return strokes in two triggered lightning flashes. One flash contained 19 strokes and the other 20 strokes for which direct measurements were available of the return stroke peak current at ground. Peak currents ranged from 1.6 to 21 kA. The measurements of peak relative light intensity were obtained from photographic streak recordings using calibrated film and microsecond resolution. Correlations, significant at better than the 0.1 percent level, were found for several functional relationships. Although a relation between L(R) and I(R) is evident in these data, none of the analytical relations considered is clearly favored. The correlation between L(R) and the maximum rate of current rise is also examined, but less correlation than between L(R) and I(R) is found. In addition, the peak relative intensity near ground is evaluated for 22 dart leaders, and a mean ratio of peak dart leader to peak return stroke relative light intensity was found to be 0.1 with a range of 0.02-0.23. Using two different methods, the peak current near ground in these dart leaders is estimated to range from 0.1 to 6 kA.

Two-dimensional velocity, optical risetime, and peak current estimates for natural positive lightning return strokes

NASA Technical Reports Server (NTRS)

Mach, Douglas M.; Rust, W. D.

1993-01-01

Velocities, optical risetimes, and transmission line model peak currents for seven natural positive return strokes are reported. The average 2D positive return stroke velocity for channel segments of less than 500 m in length starting near the base of the channel is 0.8 +/- 0.3 x 10 exp 8 m/s, which is slower than the present corresponding average velocity for natural negative first return strokes of 1.7 +/- 0.7 x 10 exp 8/s. It is inferred that positive stroke peak currents in the literature, which assume the same velocity as negative strokes, are low by a factor of 2. The average 2D positive return stroke velocity for channel segments of greater than 500 m starting near the base of the channel is 0.9 +/- 0.4 x 10 exp 8 m/s. The corresponding average velocity for the present natural negative first strokes is 1.2 +/- 0.6 x 10 exp 8 m/s. No significant velocity change with height is found for positive return strokes.

Strontium isotope investigation of ungulate movement patterns on the Pleistocene Paleo-Agulhas Plain of the Greater Cape Floristic Region, South Africa

NASA Astrophysics Data System (ADS)

Copeland, Sandi R.; Cawthra, Hayley C.; Fisher, Erich C.; Lee-Thorp, Julia A.; Cowling, Richard M.; le Roux, Petrus J.; Hodgkins, Jamie; Marean, Curtis W.

2016-06-01

Middle Stone Age sites located within the Greater Cape Floristic Region on the South African southern coast have material culture with early evidence for key modern human behaviors such as projectile weaponry, large animal hunting, and symbolic behavior. In order to interpret how and why these changes evolved, it is necessary to understand their ecological context as it has direct relevance to foraging behavior. During periods of lowered sea level, a largely flat and vast expanse of land existed south of the modern coastline, but it is now submerged by higher sea levels. This exposed area, the Paleo-Agulhas Plain, likely created an ecological context unlike anything in the region today, as evidenced by fossil assemblages dominated by migratory ungulates. One hypothesis is that the Paleo-Agulhas Plain supported a migration ecosystem of large grazers driven by summer rainfall, producing palatable forage during summer in the east, and winter rainfall, producing palatable forage during winter in the west. Alternatively, ungulates may have been moving from the coastal plain in the south to the interior north of the Cape Fold Mountains, as observed for elephants in historic times. In this study, we assess ungulate movement patterns with inter- and intra-tooth enamel samples for strontium isotopes in fossil fauna from Pinnacle Point sites PP13B and PP30. To accomplish our goals we created a bioavailable 87Sr/86Sr isoscape for the region by collecting plants at 171 sampling sites and developing a geospatial model. The strontium isotope results indicate that ungulates spent most of their time on the Paleo-Agulhas Plain and avoided dissected plain, foothill, and mountain habitats located more than about 15 km north of the modern coastline. The results clearly exclude a north-south (coastal-interior) movement or migration pattern, and cannot falsify the east-west movements hypothesized in the south coast migration ecosystem hypothesis.

Strontium isotope investigation of ungulate movement patterns on the Pleistocene Paleo-Agulhas Plain of the Greater Cape Floristic Region, South Africa

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

Copeland, Sandi R.; Cawthra, Hayley C.; Fisher, Erich C.

Middle Stone Age sites located within the Greater Cape Floristic Region on the South African southern coast have material culture with early evidence for key modern human behaviors such as projectile weaponry, large animal hunting, and symbolic behavior. In order to interpret how and why these changes evolved, it is necessary to understand their ecological context as it has direct relevance to foraging behavior. During periods of lowered sea level, a largely flat and vast expanse of land existed south of the modern coastline, but it is now submerged by higher sea levels. This exposed area, the Paleo-Agulhas Plain, likelymore » created an ecological context unlike anything in the region today, as evidenced by fossil assemblages dominated by migratory ungulates. One hypothesis is that the Paleo-Agulhas Plain supported a migration ecosystem of large grazers driven by summer rainfall, producing palatable forage during summer in the east, and winter rainfall, producing palatable forage during winter in the west. Furthermore, ungulates may have been moving from the coastal plain in the south to the interior north of the Cape Fold Mountains, as observed for elephants in historic times.« less

Strontium isotope investigation of ungulate movement patterns on the Pleistocene Paleo-Agulhas Plain of the Greater Cape Floristic Region, South Africa

DOE PAGES

Copeland, Sandi R.; Cawthra, Hayley C.; Fisher, Erich C.; ...

2016-04-16

Middle Stone Age sites located within the Greater Cape Floristic Region on the South African southern coast have material culture with early evidence for key modern human behaviors such as projectile weaponry, large animal hunting, and symbolic behavior. In order to interpret how and why these changes evolved, it is necessary to understand their ecological context as it has direct relevance to foraging behavior. During periods of lowered sea level, a largely flat and vast expanse of land existed south of the modern coastline, but it is now submerged by higher sea levels. This exposed area, the Paleo-Agulhas Plain, likelymore » created an ecological context unlike anything in the region today, as evidenced by fossil assemblages dominated by migratory ungulates. One hypothesis is that the Paleo-Agulhas Plain supported a migration ecosystem of large grazers driven by summer rainfall, producing palatable forage during summer in the east, and winter rainfall, producing palatable forage during winter in the west. Furthermore, ungulates may have been moving from the coastal plain in the south to the interior north of the Cape Fold Mountains, as observed for elephants in historic times.« less

A study of the variability in the Benguela Current volume transport

NASA Astrophysics Data System (ADS)

Majumder, Sudip; Schmid, Claudia

2018-04-01

The Benguela Current forms the eastern limb of the subtropical gyre in the South Atlantic and transports a blend of relatively fresh and cool Atlantic water and relatively warm and salty Indian Ocean water northwestward. Therefore, it plays an important role not only for the local freshwater and heat budgets but for the overall meridional heat and freshwater transport in the South Atlantic. Historically, the Benguela Current region is relatively data sparse, especially with respect to long-term velocity observations. A new three-dimensional data set of the horizontal velocity in the upper 2000 m that covers the years 1993 to 2015 is used to analyze the variability in the Benguela Current. This data set was derived using observations from Argo floats, satellite sea surface height, and wind fields. Since Argo floats do not cover regions shallower than 1000 m, the data set has gaps inshore. The main features of the horizontal circulation observed in this data set are in good agreement with those from earlier studies based on limited observations. Therefore, it can be used for a more detailed study of the flow pattern as well as the variability in the circulation in this region. It is found that the mean meridional transport in the upper 800 m between the continental shelf of Africa and 3° E, decreases from 23 ± 3 Sv (1 Sv = 106 m3 s-1) at 31° S to 11 ± 3 Sv at 28° S. In terms of variability, the 23-year long time series at 30 and 35° S reveals phases with large energy densities at periods of 3 to 7 months, which can be attributed to the occurrence of Agulhas rings in this region. The prevalence of Agulhas rings is also behind the fact that the energy density at 35° S at the annual period is smaller than at 30° S because the former latitude is closer to Agulhas Retroflection and therefore more likely to be impacted by the Agulhas rings. In agreement with this, the energy density associated with mesoscale variability at 30° S is weaker than at 35° S. With

The effects of return current and target charging in short pulse high intensity laser interactions

NASA Astrophysics Data System (ADS)

Beg, Farhat

2003-10-01

Since the introduction of the technique of chirped pulse amplification (CPA), peak laser intensities have increased dramatically. It is now possible to perform laser-plasma interaction experiments at intensities approaching 1021 Wcm-2. The electrons in the field of such lasers are highly relativistic (gamma 31) and the temperature of the hot electron distribution produced in a plasma at such extreme intensities can exceed 10 MeV. Since the resulting beam current exceeds the Alfvén limit, a neutralizing return current of cold plasma electrons moving in the opposite direction is produced. Another source of return current is that due to the escape of very energetic electrons from the target, which then creates a large electrostatic potential due to charge separation. These return currents can cause significant ohmic heating. We present results from experiments performed at Rutherford Appleton Laboratory using the VULCAN laser facility (I> 5 x1019 Wcm-2). Single wire targets were used and in some shots a secondary wire or foil was placed near the target. Three main observations were made: (i) generation of a Z-pinch in the wire due to the return current, (ii) optical transition radiation at 2w and (iii) proton emission from both the primary wire target and the secondary wire or foil. The Z-pinch was observed to be m=0 unstable. The current was estimated to be about 0.8 MA using simple energy balance considerations. Intense second harmonic emission due to coherent optical transition radiation from both the primary target and secondary objects was observed and is likely due to electron bunches accelerated by the ponderomotive jxB force of the laser. The proton emission from the secondary wire or foil was likely due to field emission of electrons from the these objects in response to the large potential produced from charging of the primary target. Results of simulations to model these interactions will also be presented.

Current status and environment impact of direct straw return in China's cropland - A review.

PubMed

Li, Hui; Dai, Mingwei; Dai, Shunli; Dong, Xinju

2018-09-15

With the development of grain production technologies and improvement of rural living standard, the production and utilization of straw have significantly been changed in China. More than 1 billion tones of straw are produced per year, and vast amount of them are discarded without effective utilization, leading various environmental and social impacts. Straw return is an effective approach of the straw utilization that has been greatly recommended by government and scientists in China. This paper discussed the current status of the straw return in China. Specifically, the production and models of straw return were explored and their environmental impacts were extensively evaluated. It was concluded that straw could be positively effective on the improvement of the soil quality and the grain production. However, it appeared that the straw return also had several neglect negative effects, implying that further research and assessment on the returned straw are required before its large-scale promotion in China. Copyright © 2018 Elsevier Inc. All rights reserved.

JSC Advanced Curation: Research and Development for Current Collections and Future Sample Return Mission Demands

NASA Technical Reports Server (NTRS)

Fries, M. D.; Allen, C. C.; Calaway, M. J.; Evans, C. A.; Stansbery, E. K.

2015-01-01

Curation of NASA's astromaterials sample collections is a demanding and evolving activity that supports valuable science from NASA missions for generations, long after the samples are returned to Earth. For example, NASA continues to loan hundreds of Apollo program samples to investigators every year and those samples are often analyzed using instruments that did not exist at the time of the Apollo missions themselves. The samples are curated in a manner that minimizes overall contamination, enabling clean, new high-sensitivity measurements and new science results over 40 years after their return to Earth. As our exploration of the Solar System progresses, upcoming and future NASA sample return missions will return new samples with stringent contamination control, sample environmental control, and Planetary Protection requirements. Therefore, an essential element of a healthy astromaterials curation program is a research and development (R&D) effort that characterizes and employs new technologies to maintain current collections and enable new missions - an Advanced Curation effort. JSC's Astromaterials Acquisition & Curation Office is continually performing Advanced Curation research, identifying and defining knowledge gaps about research, development, and validation/verification topics that are critical to support current and future NASA astromaterials sample collections. The following are highlighted knowledge gaps and research opportunities.

Influence of channel base current and varying return stroke speed on the calculated fields of three important return stroke models

NASA Technical Reports Server (NTRS)

Thottappillil, Rajeev; Uman, Martin A.; Diendorfer, Gerhard

1991-01-01

Compared here are the calculated fields of the Traveling Current Source (TCS), Modified Transmission Line (MTL), and the Diendorfer-Uman (DU) models with a channel base current assumed in Nucci et al. on the one hand and with the channel base current assumed in Diendorfer and Uman on the other hand. The characteristics of the field wave shapes are shown to be very sensitive to the channel base current, especially the field zero crossing at 100 km for the TCS and DU models, and the magnetic hump after the initial peak at close range for the TCS models. Also, the DU model is theoretically extended to include any arbitrarily varying return stroke speed with height. A brief discussion is presented on the effects of an exponentially decreasing speed with height on the calculated fields for the TCS, MTL, and DU models.

Agulhas leakage dynamics affects decadal variability in Atlantic overturning circulation.

PubMed

Biastoch, A; Böning, C W; Lutjeharms, J R E

2008-11-27

Predicting the evolution of climate over decadal timescales requires a quantitative understanding of the dynamics that govern the meridional overturning circulation (MOC). Comprehensive ocean measurement programmes aiming to monitor MOC variations have been established in the subtropical North Atlantic (RAPID, at latitude 26.5 degrees N, and MOVE, at latitude 16 degrees N) and show strong variability on intraseasonal to interannual timescales. Observational evidence of longer-term changes in MOC transport remains scarce, owing to infrequent sampling of transoceanic sections over past decades. Inferences based on long-term sea surface temperature records, however, supported by model simulations, suggest a variability with an amplitude of +/-1.5-3 Sv (1 Sv = 10(6) m(3) s(-1)) on decadal timescales in the subtropics. Such variability has been attributed to variations of deep water formation in the sub-arctic Atlantic, particularly the renewal rate of Labrador Sea Water. Here we present results from a model simulation that suggest an additional influence on decadal MOC variability having a Southern Hemisphere origin: dynamic signals originating in the Agulhas leakage region at the southern tip of Africa. These contribute a MOC signal in the tropical and subtropical North Atlantic that is of the same order of magnitude as the northern source. A complete rationalization of observed MOC changes therefore also requires consideration of signals arriving from the south.

The Student Returns: Challenges of the Returning Student.

ERIC Educational Resources Information Center

Marino, Carrie A.

According to a 1994 analysis of returning students, as many as 43% of all college students are currently over the age of 24. This influx of returning students demands a new look at existing pedagogical practices. The changing demographics of the classroom turn age and life experience into a consideration for pedagogy alongside race, class, and…

Return current instability driven by a temperature gradient in ICF plasmas

NASA Astrophysics Data System (ADS)

Rozmus, W.; Brantov, A. V.; Sherlock, M.; Bychenkov, V. Yu

2018-01-01

Hot plasmas with strong temperature gradients in inertial confinement fusion experiments are examined for ion acoustic instabilities produced by electron heat flow. The return current instability (RCI) due to a neutralizing current of cold electrons arising in response to a large electron heat flux has been considered. First, the linear threshold and growth rates are derived in the non-local regime of thermal transport. They are compared with the results of Vlasov-Fokker-Planck (VFP) simulations in one spatial dimension. Very good agreement has been found between kinetic VFP simulations and the linear theory of the RCI. A quasi-stationary state of ion acoustic turbulence (IAT) produced by the RCI is achieved in the VFP simulations. Saturation of the RCI involves heating of ions in the tail of the ion distribution function and convection of the enhanced ion acoustic fluctuations from the unstable region of the plasma. Further evolution of the IAT and its effects on absorption and transport are also discussed.

A study on the influence of corona on currents and electromagnetic fields predicted by a nonlinear lightning return-stroke model

NASA Astrophysics Data System (ADS)

De Conti, Alberto; Silveira, Fernando H.; Visacro, Silvério

2014-05-01

This paper investigates the influence of corona on currents and electromagnetic fields predicted by a return-stroke model that represents the lightning channel as a nonuniform transmission line with time-varying (nonlinear) resistance. The corona model used in this paper allows the calculation of corona currents as a function of the radial electric field in the vicinity of the channel. A parametric study is presented to investigate the influence of corona parameters, such as the breakdown electric field and the critical electric field for the stable propagation of streamers, on predicted currents and electromagnetic fields. The results show that, regardless of the assumed corona parameters, the incorporation of corona into the nonuniform and nonlinear transmission line model under investigation modifies the model predictions so that they consistently reproduce most of the typical features of experimentally observed lightning electromagnetic fields and return-stroke speed profiles. In particular, it is shown that the proposed model leads to close vertical electric fields presenting waveforms, amplitudes, and decay with distance in good agreement with dart leader electric field changes measured in triggered lightning experiments. A comparison with popular engineering return-stroke models further confirms the model's ability to predict consistent electric field waveforms in the close vicinity of the channel. Some differences observed in the field amplitudes calculated with the different models can be related to the fact that current distortion, while present in the proposed model, is ultimately neglected in the considered engineering return-stroke models.

Electron Beam Return-Current Losses in Solar Flares: Initial Comparison of Analytical and Numerical Results

NASA Technical Reports Server (NTRS)

Holman, Gordon

2010-01-01

Accelerated electrons play an important role in the energetics of solar flares. Understanding the process or processes that accelerate these electrons to high, nonthermal energies also depends on understanding the evolution of these electrons between the acceleration region and the region where they are observed through their hard X-ray or radio emission. Energy losses in the co-spatial electric field that drives the current-neutralizing return current can flatten the electron distribution toward low energies. This in turn flattens the corresponding bremsstrahlung hard X-ray spectrum toward low energies. The lost electron beam energy also enhances heating in the coronal part of the flare loop. Extending earlier work by Knight & Sturrock (1977), Emslie (1980), Diakonov & Somov (1988), and Litvinenko & Somov (1991), I have derived analytical and semi-analytical results for the nonthermal electron distribution function and the self-consistent electric field strength in the presence of a steady-state return-current. I review these results, presented previously at the 2009 SPD Meeting in Boulder, CO, and compare them and computed X-ray spectra with numerical results obtained by Zharkova & Gordovskii (2005, 2006). The phYSical significance of similarities and differences in the results will be emphasized. This work is supported by NASA's Heliophysics Guest Investigator Program and the RHESSI Project.

Changing sediment physical properties at the Agulhas Plateau (IODP Site U1475): indications for the long-term variability of deepwater circulation over the last 7 Ma

NASA Astrophysics Data System (ADS)

Gruetzner, Jens; Lathika, Nambiyathodi; Jimenez Espejo, Francisco J.; Uenzelmann-Neben, Gabriele

2017-04-01

The gateway south of South Africa constitutes an integral inter-ocean link in the global thermohaline circulation (THC) since it allows the exchange of shallow- and deepwater masses between the Indian and the Atlantic. Thus understanding past variations of this current system is important for improving our knowledge of the global climate. The long-term changes in deepwater flow in the Atlantic-Indian gateway during the Cenozoic have been initially studied using reflection seismic profiles. But in many cases the seismic stratigraphy is poorly constrained and not further resolved within the time period from the late Miocene to present. In particular, there are limited Pliocene records that can be used to investigate the influence of climatic (e.g. Antartic ice volume) and tectonic (e.g. closure of the central American seaway) on the deep-water variability. Here we focus on the bottom water flow around the Agulhas Plateau, a location proximal to the entrance of North Atlantic Deep Water (NADW) to the Southern Ocean and South Indian Ocean. IODP Expedition 361 (SAFARI) Site U1475 was drilled in 2669 m water depth into a sediment drift that is deposited on the southwestern flank of Agulhas Plateau and comprises a complete stratigraphic section of the last 7 Ma. We present cleaned, edited, and spliced high-resolution data sets of sediment physical properties measured at Site U1475. Synthetic seismograms generated from the velocity and bulk density core scanning records allow a detailed correlation oft the drilling results with the Site survey seismic reflection profiles. Seismic reflectors at 3.75 and 3.87 s (two-way-traveltime) correspond to major increases in acoustic impedance at 110 and 216 meters below seafloor. Based on the preliminary shipboard biostratigraphic age model sediments at these depths have ages of 4.0 and 5.1 Ma, respectively. Furthermore spectral analyses of physical property records such as natural gamma radiation and colour reflectance reveal climate

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.

Return current instability driven by a temperature gradient in ICF plasmas

DOE PAGES

Rozmus, W.; Brantov, A. V.; Sherlock, M.; ...

2017-10-12

Here, hot plasmas with strong temperature gradients in inertial confinement fusion (ICF) experiments are examined for ion acoustic instabilities produced by electron heat flow. The return current instability (RCI) due to a neutralizing current of cold electrons arising in response to a large electron heat flux has been considered. First, the linear threshold and growth rates are derived in the nonlocal regime of thermal transport. They are compared with the results of Vlasov-Fokker-Planck (VFP) simulations in one spatial dimension. Very good agreement has been found between kinetic VFP simulations and the linear theory of the RCI. A quasi-stationary state ofmore » ion acoustic turbulence produced by the RCI is achieved in the VFP simulations. Saturation of the RCI involves heating of ions in the tail of the ion distribution function and convection of the enhanced ion acoustic fluctuations from the unstable region of the plasma. Further evolution of the ion acoustic turbulence and its effects on absorption and transport are also discussed.« less

Determinants of return behavior: a comparison of current and lapsed donors.

PubMed

Germain, Marc; Glynn, Simone A; Schreiber, George B; Gélinas, Stéphanie; King, Melissa; Jones, Mike; Bethel, James; Tu, Yongling

2007-10-01

There is a need to identify factors explaining why some people stop donating blood. A random mail survey of first-time (FT) and repeat (RPT) current (donating within 6 months before survey) and lapsed (donating >2 years prior) donors was conducted. The self-administered questionnaire included questions on personal, social, and behavioral characteristics. Among 1280 current and 1672 lapsed donors with valid addresses, the participation rate was 66.8 and 39.2 percent, respectively. In FT donors, the odds of lapsing increased with education (odds ratio [OR], 2.18; 95% confidence interval [CI], 1.34-3.55 for college or higher vs. Grade 12 or less education). Lapsed FT donors were more often asked to donate (OR, 1.89; 95% CI, 1.32-2.70) and had less interest in incentives (p < 0.001) than current FT donors. In RPT donors, lapsed status was associated with being younger (p < 0.001) and female (OR, 1.19; 95% CI, 1.00-1.42). Lapsed status was inversely associated with satisfaction with the last donation experience in both FT (p = 0.043) and RPT (p < 0.001) donors. Lapsed and current donors did not differ in perceived need for blood, personal transfusion experience, or mean reported altruistic behavior score. A positive donation experience appears to be a major determinant of donor return behavior. Lapsed donors do not appear, on average, to engage in fewer altruistic behaviors than currently active donors. Retention marketing strategies that appeal solely to altruistic values need to be further evaluated for their effectiveness.

Current thinking: return to play and transient quadriplegia.

PubMed

Cantu, Robert V; Cantu, Robert C

2005-02-01

Athletes that participate in contact and collision sports assume risk of serious injury each time they take the field. For those athletes that have sustained an episode of transient quadriplegia, the decision of whether to return to competition can be a difficult one. Some athletes, realizing how close they may have come to permanent injury, may decide that further participation is not in their best interest. Others may be somewhat undecided, and some may want to return at all costs. As the treating physician, the goal is to identify those athletes who after a single episode of transient quadriplegia are at increased risk for further injury and consequently should discontinue participation in contact sports. Factors that may contribute to that determination include mechanism of injury, prior history of neurologic symptoms or injury, and anatomic features that may predispose to further injury such as disc herniation, fracture, or cervical stenosis.

Long-term geomagnetically induced current observations in New Zealand: Earth return corrections and geomagnetic field driver

NASA Astrophysics Data System (ADS)

Mac Manus, Daniel H.; Rodger, Craig J.; Dalzell, Michael; Thomson, Alan W. P.; Clilverd, Mark A.; Petersen, Tanja; Wolf, Moritz M.; Thomson, Neil R.; Divett, Tim

2017-08-01

Transpower New Zealand Limited has measured DC currents in transformer neutrals in the New Zealand electrical network at multiple South Island locations. Near-continuous archived DC current data exist since 2001, starting with 12 different substations and expanding from 2009 to include 17 substations. From 2001 to 2015 up to 58 individual transformers were simultaneously monitored. Primarily, the measurements were intended to monitor the impact of the high-voltage DC system linking the North and South Islands when it is operating in "Earth return" mode. However, after correcting for Earth return operation, as described here, the New Zealand measurements provide an unusually long and spatially detailed set of geomagnetically induced current (GIC) measurements. We examine the peak GIC magnitudes observed from these observations during two large geomagnetic storms on 6 November 2001 and 2 October 2013. Currents of 30-50 A are observed, depending on the measurement location. There are large spatial variations in the GIC observations over comparatively small distances, which likely depend upon network layout and ground conductivity. We then go on to examine the GIC in transformers throughout the South Island during more than 151 h of geomagnetic storm conditions. We compare the GIC to the various magnitude and rate of change components of the magnetic field. Our results show that there is a strong correlation between the magnitude of the GIC and the rate of change of the horizontal magnetic field (H'). This correlation is particularly clear for transformers that show large GIC current during magnetic storms.

Factors influencing donor return.

PubMed

Schlumpf, Karen S; Glynn, Simone A; Schreiber, George B; Wright, David J; Randolph Steele, Whitney; Tu, Yongling; Hermansen, Sigurd; Higgins, Martha J; Garratty, George; Murphy, Edward L

2008-02-01

To predict future blood donation behavior and improve donor retention, it is important to understand the determinants of donor return. A self-administered questionnaire was completed in 2003 by 7905 current donors. With data mining methods, all factors measured by the survey were ranked as possible predictors of actual return within 12 months. Significant factors were analyzed with logistic regression to determine predictors of intention and of actual return. Younger and minority donors were less likely to return in 12 months. Predictors of donor return were higher prior donation frequency, higher intention to return, a convenient place to donate, and having a good donation experience. Most factors associated with actual donor return were also associated with a high intention to return. Although not significant for actual return, feeling a responsibility to help others, higher empathetic concern, and a feeling that being a blood donor means more than just donating blood were related to high intention to return. Prior donation frequency, intention to return, donation experience, and having a convenient location appear to significantly predict donor return. Clearly, donor behavior is dependent on more than one factor alone. Altruistic behavior, empathy, and social responsibility items did not enter our model to predict actual return. A donor's stated intention to give again is positively related to actual return and, while not a perfect measure, might be a useful proxy when donor return cannot be determined.

A comparison of the structure, properties, and water mass composition of quasi-isotropic eddies in western boundary currents in an eddy-resolving ocean model

NASA Astrophysics Data System (ADS)

Rykova, Tatiana; Oke, Peter R.; Griffin, David A.

2017-06-01

Using output from a near-global eddy-resolving ocean model, we analyse the properties and characteristics of quasi-isotropic eddies in five Western Boundary Current (WBC) regions, including the extensions of the Agulhas, East Australian Current (EAC), Brazil-Malvinas Confluence (BMC), Kuroshio and Gulf Stream regions. We assess the model eddies by comparing to satellite and in situ observations, and show that most aspects of the model's representation of eddies are realistic. We find that the mean eddies differ dramatically between these WBC regions - all with some unique and noteworthy characteristics. We find that the vertical displacement of isopycnals of Agulhas eddies is the greatest, averaging 350-450 m at depths of over 800-900 m. EAC (BMC) eddies are the least (most) barotropic, with only 50% (85-90%) of the velocity associated with the barotropic mode. Kuroshio eddies are the most stratified, resulting in small isopycnal displacement, even for strong eddies; and Gulf Stream eddies carry the most heat. Despite their differences, we explicitly show that the source waters for anticyclonic eddies are a mix of the WBC water (from the boundary current itself) and water that originates equatorward of the WBC eddy-field; and cyclonic eddies are a mix of WBC water and water that originates poleward of the WBC eddy-field.

South African Climates: Highlights From International Ocean Discovery Program Expedition 361

NASA Astrophysics Data System (ADS)

Hemming, S. R.; Hall, I. R.; LeVay, L.

2016-12-01

International Ocean Discovery Program Expedition 361 drilled six sites on the southeast African margin and in the Indian-Atlantic ocean gateway, southwest Indian Ocean, from 30 January to 31 March 2016. In total, 5175 m of core was recovered, with an average recovery of 102%, during 29.7 days of on-site operations. The sites, situated in the Mozambique Channel, at locations directly influenced by discharge from the Zambezi and Limpopo River catchments, the Natal Valley, the Agulhas Plateau, and the Cape Basin were targeted to reconstruct the history of the Greater Agulhas Current System over the past 5 Ma. The Agulhas Current transports 70 Sv of warm and saline surface waters from the tropical Indian Ocean along the East African margin to the tip of Africa. Exchanges of heat and moisture with the atmosphere influence southern African rainfall patterns. Recent ocean model and paleoceanographic data further point at a potential role of the Agulhas Current in controlling the strength and mode of the Atlantic Meridional Overturning Circulation (AMOC) during the Late Pleistocene. The main objectives of the expedition were to document the oceanographic properties of the Agulhas Current through tectonic and climatic changes during the Plio-Pleistocene, to determine the dynamics of the Indian-Atlantic gateway circulation during this time, to examine the connection of the Agulhas leakage and AMOC, to address the influence of the Agulhas Current on African terrestrial climates and potential links to Human evolution. Additionally, the Expedition set out to fulfill the needs of the Ancillary Project Letter, consisting of high-resolution interstitial water samples that will, and to constrain the temperature and salinity profiles of the ocean during the Last Glacial Maximum. Here we highlight some of the expedition successes and show how it has made major strides toward fulfilling each of these objectives. The recovered sequences allowed complete spliced stratigraphic sections

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.

Dynamics of a lightning corona sheath—A constant field approach using the generalized traveling current source return stroke model

NASA Astrophysics Data System (ADS)

Cvetic, Jovan; Heidler, Fridolin; Markovic, Slavoljub; Radosavljevic, Radovan; Osmokrovic, Predrag

2012-11-01

A generalized lightning traveling current source return stroke model has been used to examine the characteristics of the lightning channel corona sheath surrounding a thin channel core. A model of the lightning channel consisting of a charged corona sheath and a narrow, highly conducting central core that conducts the main current flow is assumed. Strong electric field, with a predominant radial direction, has been created during the return stroke between the channel core and the outer channel sheath containing the negative charge. The return stroke process is modeled with the positive charge coming from the channel core discharging the negative leader charge in the corona sheath. The corona sheath model that predicts the charge motion in the sheath is used to derive the expressions of the sheath radius vs. time during the return stroke. According to the corona sheath model proposed earlier by Maslowski and Rakov (2006) and Maslowski et al. (2009), it consists of three zones, zone 1 (surrounding channel core with net positive charge), zone 2 (surrounding zone 1 with negative charge) and zone 3 (outer zone representing the virgin air without charges). We adopted the assumption of a constant electric field inside zone 1 of the corona sheath observed in the experimental research of corona discharges in a coaxial geometry by Cooray (2000). This assumption seems to be more realistic than the assumption of a uniform corona space charge density used previously in the study of Maslowski and Rakov (2006), Marjanovic and Cvetic (2009), and Tausanovic et al. (2010). Applying the Gauss' law on the infinitesimally small cylindrical section of the channel the expressions for time-dependence of the radii of zones 1 and 2 during the return stroke are derived. The calculations have shown that the overall channel dynamics concerning electrical discharge is roughly 50% slower and the maximum radius of zone 1 is about 33% smaller compared to the corresponding values calculated in the

46 CFR 111.05-11 - Hull return.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Hull return. 111.05-11 Section 111.05-11 Shipping COAST... REQUIREMENTS Equipment Ground, Ground Detection, and Grounded Systems § 111.05-11 Hull return. (a) A vessel's hull must not carry current as a conductor except for the following systems: (1) Impressed current...

The effect of beam-driven return current instability on solar hard X-ray bursts

NASA Technical Reports Server (NTRS)

Cromwell, D.; Mcquillan, P.; Brown, J. C.

1986-01-01

The problem of electrostatic wave generation by a return current driven by a small area electron beam during solar hard X-ray bursts is discussed. The marginal stability method is used to solve numerically the electron and ion heating equations for a prescribed beam current evolution. When ion-acoustic waves are considered, the method appears satisfactory and, following an initial phase of Coulomb resistivity in which T sub e/T sub i rise, predicts a rapid heating of substantial plasma volumes by anomalous ohmic dissipation. This hot plasma emits so much thermal bremsstrahlung that, contrary to previous expectations, the unstable beam-plasma system actually emits more hard X-rays than does the beam in the purely collisional thick target regime relevant to larger injection areas. Inclusion of ion-cyclotron waves results in ion-acoustic wave onset at lower T sub e/T sub i and a marginal stability treatment yields unphysical results.

Absolute geostrophic currents over the SR02 section south of Africa in December 2009

NASA Astrophysics Data System (ADS)

Tarakanov, Roman

2017-04-01

The structure of the absolute geostrophic currents is investigated on the basis of CTD-, SADCP- and LADCP-data over the hydrographic section occupied south of Africa from the Good Hope Cape to 57° S along the Prime Meridian, and on the basis of satellite data on absolute dynamic topography (ADT) produced by Ssalto/Duacs and distributed by Aviso, with a support from Cnes (http://www.aviso.altimetry.fr/duacs/). Thus the section crossed the subtropical zone (at the junction of the subtropical gyres of the Indian and Atlantic oceans), the Antarctic Circumpolar Current (ACC) and terminated at the northern periphery of the Weddell Gyre. A total of 87 stations were occupied here with CTD-, and LADCP-profiling in the entire water column. The distance between stations was 20 nautical miles. Absolute geostrophic currents were calculated between each pair of CTD-stations with barotropic correction based on two methods: by SADCP data and by ADT at these stations. The subtropical part of the section crossed a large segment of the Agulhas meander, already separated from the current and disintegrating into individual eddies. In addition, smaller formed cyclones and anticyclones of the Agulhas Current were also observed in this zone. These structural elements of the upper layer of the ocean currents do not penetrate deeper than 1000-1500 m. Oppositely directed barotropic currents with velocities up to 30 cm/s were observed below these depths extending to the ocean bottom. Such large velocities agree well with the data of the bottom tracking of Lowered ADCP. Only these data were the reliable results of LADCP measurements because of the high transparency of the deep waters of the subtropical zone. The total transport of absolute geostrophic currents in the section is estimated as 144 and 179 Sv to the east, based on the SADCP and ADT barotropic correction, respectively. A transport of 4 (2) Sv to the east was observed on the northern periphery of the Weddell Gyre, 187 (182) Sv to

Return on Investment from Biochar Application

USDA-ARS?s Scientific Manuscript database

Current literature has yet to fully address the cost of biochar application or the return on investment to the grower. The objectives were to identify possible on-farm spreader equipment, spreader capacity, application expenses, and rate of return needed for growers to apply biochar economically. Bi...

Return to Duty Rate of Amputee Soldiers in the Current Conflicts in Afghanistan and Iraq

DTIC Science & Technology

2010-06-01

Conclusion: During the 1980s , 11 of 469 amputees returned to active duty (2.3%). The number of amputees returning to duty has increased signifi- cantly...between 1980 and 1988, but only 11 of the 469 (2.3%) remained on active duty. The purpose of this study was to evaluate the return to duty rate of...During the 1980s and 1990s, no such designated military amputee centers were in operation. This may be one reason for the lower return to duty rate of

41 CFR 101-27.501 - Eligibility for return.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true Eligibility for return. 101-27.501 Section 101-27.501 Public Contracts and Property Management Federal Property Management...-Return of GSA Stock Items § 101-27.501 Eligibility for return. GSA stock items for which no current or...

Effect of Current-Use Valuation on Forestry Investment Returns in Selected Virginia Counties

Treesearch

Peter D. Gayer; Harry L. Haney; Clifford A. Hickman

1987-01-01

Results from three Virginia counties indicate that if forest properties are taxed on the basis of their value for continued timber growing as opposed to their fair market value, forestry investment returns will be increased. Where development pressures were insignificant, real returns roseby less than $40 per acre when measured in terms of Net Present Value (NPV) and...

Automated detection of Lagrangian eddies and coherent transport of heat and salinity in the Agulhas leakage

NASA Astrophysics Data System (ADS)

Huhn, Florian; Haller, George

2014-05-01

Haller and Beron-Vera(2013) have recently introduced a new objective method to detect coherent Lagrangian eddies in turbulence. They find that closed null-geodesics of a generalized Green-Lagrange strain tensor act as coherent Lagrangian eddy boundaries, showing near-zero and uniform material stretching. We make use of this method to develop an automated detection procedure for coherent Lagrangian eddies in large-scale ocean data. We apply our results to a recent 3D general circulation model, the Southern Ocean State Estimate (SOSE), with focus on the South Atlantic Ocean and the inter-ocean exchange between the Indian and Atlantic ocean. We detect a large number of coherent Lagrangian eddies and present statistics of their properties. The largest and most circular eddy boundaries represent Lagrangian Agulhas rings. Circular regions inside these rings with higher temperature and salinity than the surrounding waters can be explained by the coherent eddy boundaries that enclose and isolate the eddy interiors. We compare eddy boundaries at different depths with eddy boundaries obtained from geostrophic velocities derived from the model's sea surface height (SSH). The transport of mass, heat and salinity enclosed by coherent eddies through a section in the Cape basin is quantified and compared to the non-coherent transport by the background flow.

21 CFR 211.204 - Returned drug products.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 4 2011-04-01 2011-04-01 false Returned drug products. 211.204 Section 211.204 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR FINISHED PHARMACEUTICALS Returned and Salvaged Drug...

21 CFR 211.204 - Returned drug products.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 4 2013-04-01 2013-04-01 false Returned drug products. 211.204 Section 211.204 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR FINISHED PHARMACEUTICALS Returned and Salvaged Drug...

21 CFR 211.204 - Returned drug products.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 4 2014-04-01 2014-04-01 false Returned drug products. 211.204 Section 211.204 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR FINISHED PHARMACEUTICALS Returned and Salvaged Drug...

21 CFR 211.204 - Returned drug products.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 4 2012-04-01 2012-04-01 false Returned drug products. 211.204 Section 211.204 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR FINISHED PHARMACEUTICALS Returned and Salvaged Drug...

21 CFR 211.204 - Returned drug products.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Returned drug products. 211.204 Section 211.204 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR FINISHED PHARMACEUTICALS Returned and Salvaged Drug...

Potential of space-borne GNSS reflectometry to constrain simulations of the ocean circulation. A case study for the South African current system

NASA Astrophysics Data System (ADS)

Saynisch, Jan; Semmling, Maximilian; Wickert, Jens; Thomas, Maik

2015-11-01

The Agulhas current system transports warm and salty water masses from the Indian Ocean into the Southern Ocean and into the Atlantic. The transports impact past, present, and future climate on local and global scales. The size and variability, however, of the respective transports are still much debated. In this study, an idealized model based twin experiment is used to study whether sea surface height (SSH) anomalies estimated from reflected signals of the Global Navigation Satellite System reflectometry (GNSS-R) can be used to determine the internal water mass properties and transports of the Agulhas region. A space-borne GNSS-R detector on the International Space Station (ISS) is assumed and simulated. The detector is able to observe daily SSH fields with a spatial resolution of 1-5∘. Depending on reflection geometry, the precision of a single SSH observation is estimated to reach 3 cm (20 cm) when the carrier phase (code delay) information of the reflected GNSS signal is used. The average precision over the Agulhas region is 7 cm (42 cm). The proposed GNSS-R measurements surpass the radar-based satellite altimetry missions in temporal and spatial resolution but are less precise. Using the estimated GNSS-R characteristics, measurements of SSH are generated by sampling a regional nested general circulation model of the South African oceans. The artificial observations are subsequently assimilated with a 4DVAR adjoint data assimilation method into the same ocean model but with a different initial state and forcing. The assimilated and the original, i.e., the sampled model state, are compared to systematically identify improvements and degradations in the model variables that arise due to the assimilation of GNSS-R based SSH observations. We show that SSH and the independent, i.e., not assimilated model variables velocity, temperature, and salinity improve by the assimilation of GNSS-R based SSH observations. After the assimilation of 90 days of SSH observations

Modifying cochlear implant design: advantages of placing a return electrode in the modiolus.

PubMed

Ho, Steven Y; Wiet, Richard J; Richter, Claus-Peter

2004-07-01

A modiolar return electrode significantly increases the current flow across spiral ganglion cells into the modiolus, and may decrease the cochlear implant's power requirements. Ideal cochlear implants should maximize current flow into the modiolus to stimulate auditory neurons. Previous efforts to facilitate current flow through the modiolus included the fabrication and use of precurved electrodes designed to "hug" the modiolus and silastic positioners designed to place the electrodes closer to the modiolus. In contrast to earlier efforts, this study explores the effects of return electrode placement on current distributions in the modiolus. The effects of return electrode positioning on current flow in the modiolus were studied in a Plexiglas model of the cochlea. Results of model measurements were confirmed by measurements in the modiolus of human temporal bones. The return electrode was placed either within the modiolus, or remotely, outside the temporal bone, simulating contemporary cochlear implant configurations using monopolar stimulation. Cochlear model results clearly show that modiolar current amplitudes can be influenced significantly by the location of the return electrode, being larger when placed into the modiolus. Temporal bone data show similar findings. Voltages recorded in the modiolus are, on average, 2.8 times higher with the return electrode in the modiolus compared with return electrode locations outside the temporal bone. Placing a cochlear implant's return electrode in the modiolus should significantly reduce its power consumption. Reducing power requirements should lead to improved efficiency, safer long-term use, and longer device life.

Why does negative CG lightning have subsequent return strokes?

NASA Astrophysics Data System (ADS)

Wilkes, R. A.; Kotovsky, D. A.; Uman, M. A.; Carvalho, F. L.; Jordan, D.

2017-12-01

It is not understood why cloud-to-ground (CG) lightning flashes lowering negative charge often produce discrete dart-leader/return-stroke sequences rather than having the first stroke drain the available cloud charge, as is almost always the case for CG lightning lowering positive charge. Triggered lightning data obtained at the International Center for Lightning Research and Testing (ICLRT) in north-central Florida have been analyzed to clarify the subsequent return-stroke process. In summers 2013 through 2016 at the ICLRT, 53% of the rocket launches did not initiate any part of a lightning flash, 13% of the rocket launches created an initial stage only (ISO) and failed to produce a following dart-leader/return-stroke sequences, and 34% of rocket launches produced an initial stage (IS) followed by return strokes. The IS of the triggered lightning consists of the upward positive leader and a following initial continuing current, both being responsible for transporting negative charge from the cloud to ground. Our ISO events may well have some commonality with the roughly 20 percent of natural CG flashes that fail to produce a dart-leader/return-stroke. We have analyzed the IS of 41 triggered lightning flashes with (19 cases) and without (22 cases) following return strokes and compared areas and heights of the flash using data collected by a Lightning Mapping Array (LMA). In our preliminary analysis, we can find no geometrical feature of the lightning channel during the IS that will predict the occurrence or lack of occurrence of following return strokes. We also have compared the triggered-lightning electrical current and charge transfer observed at the ground. We found that the average current, duration, and charge transfer during the IS for ISO events is each about half that of ISs analyzed which are followed by dart-leader/return-stroke sequences, contrary to the results presented from the GCOELD in China. Summarizing, there appear to be no differences in the

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;

Impact of the Indonesian Throughflow on the Atlantic Meridional Overturning Circulation

NASA Astrophysics Data System (ADS)

Le Bars, Dewi; Dijkstra, Henk

2014-05-01

Understanding the mechanisms controlling the strength and variability of the Atlantic Meridional Overturning Circulation (AMOC) is one of the main topics of climate science and in particular physical oceanography. Current simple representations of the global ocean overturning separates the surface return flow to the Atlantic basin into a cold water path through the Drake Passage and a warm water path through the Indonesian Throughflow and Agulhas leakage. The relative importance of these two paths has been investigated in non-eddying ocean models. In these models the Agulhas retroflection cannot be modelled properly, which leads to an important overestimation of the Agulhas leakage. Furthermore, it seems that the in these models the relation between the meridional density gradient and the overturning strength is greatly simplified and changes significantly when eddies are resolved (Den Toom et al. 2013). As a result, the impact of the Pacific-Indian Oceans exchange through the Indonesian Throughflow on the AMOC is still unknown. To investigate this question we run a state-of-the-art ocean model, the Parallel Ocean Program (POP), globally, at eddy resolving resolution (0.1º). Using climatological forcing from the CORE dataset we perform two simulations of 110 years, a control experiment with realistic coastlines and one in which the Indonesian Passages are closed. Results show that, for a closed Indonesian Throughflow, the Indian Ocean cools down but its salinity increases. The Agulhas leakage reduces also by 3Sv (Le Bars et al. 2013) and the net effect on the south Atlantic is a cooling down and decrease salinity. The anomalies propagate slowly northward and a significant decrease of the AMOC is found at 26ºN after 50 years. This decrease AMOC also leads to reduced northward heat flux in the Atlantic. These processes are investigated with a detailed analysis of the heat and freshwater balances in the Atlantic-Arctic region and in the region south of 34ºS where

Return Current Electron Beams and Their Generation of "Raman" Scattering

NASA Astrophysics Data System (ADS)

Simon, A.

1998-11-01

For some years, we(A. Simon and R. W. Short, Phys. Rev. Lett. 53), 1912 (1984). have proposed that the only reasonable explanation for many of the observations of "Raman" scattering is the presence of an electron beam in the plasma. (The beam creates a bump-on-tail instability.) Two major objections to this picture have been observation of Raman when no n_c/4 surface was present, with no likely source for the electron beam, and the necessity for the initially outward directed beam to bounce once to create the proper waves. Now new observations on LLE's OMEGA(R. Petrasso et al), this conference. and at LULI(C. Labaune et al)., Phys. Plasma 5, 234 (1998). have suggested a new origin for the electron beam. This new scenario answers the previous objections, maintains electron beams as the explanation of the older experiments, and may clear up puzzling observations that have remained unexplained. The new scenario is based on two assumptions: (1) High positive potentials develop in target plasmas during their creation. (2) A high-intensity laser beam initiates spark discharges from nearby surfaces to the target plasma. The resulting return current of electrons should be much more delta-like, is initially inwardly directed, and no longer requires the continued presence of a n_c/4 surface. Scattering of the interaction beam from the BOT waves yields the observed Raman signal. Experimental observations that support this picture will be cited. ``Pulsation'' of the scattering and broadband ``flashes'' are a natural part of this scenario. This work was supported by the U.S. Department of Energy Office of Inertial Confinement Fusion under Cooperative Agreement No. DE-FC03-92SF19460.

Mars Sample Return Architecture Assessment Study

NASA Astrophysics Data System (ADS)

Centuori, S.; Hermosín, P.; Martín, J.; De Zaiacomo, G.; Colin, S.; Godfrey, A.; Myles, J.; Johnson, H.; Sachdev, T.; Ahmed, R.

2018-04-01

Current paper presents the results of ESA funded activity "Mars Sample Return Architecture Assessment Study" carried-out by DEIMOS Space, Lockheed Martin UK Ampthill, and MDA Corporation, where more than 500 mission design options have been studied.

Comparing current definitions of return to work: a measurement approach.

PubMed

Steenstra, I A; Lee, H; de Vroome, E M M; Busse, J W; Hogg-Johnson, S J

2012-09-01

Return-to-work (RTW) status is an often used outcome in work and health research. In low back pain, work is regarded as a normal activity a worker should return to in order to fully recover. Comparing outcomes across studies and even jurisdictions using different definitions of RTW can be challenging for readers in general and when performing a systematic review in particular. In this study, the measurement properties of previously defined RTW outcomes were examined with data from two studies from two countries. Data on RTW in low back pain (LBP) from the Canadian Early Claimant Cohort (ECC); a workers' compensation based study, and the Dutch Amsterdam Sherbrooke Evaluation (ASE) study were analyzed. Correlations between outcomes, differences in predictive validity when using different outcomes and construct validity when comparing outcomes to a functional status outcome were analyzed. In the ECC all definitions were highly correlated and performed similarly in predictive validity. When compared to functional status, RTW definitions in the ECC study performed fair to good on all time points. In the ASE study all definitions were highly correlated and performed similarly in predictive validity. The RTW definitions, however, failed to compare or compared poorly with functional status. Only one definition compared fairly on one time point. Differently defined outcomes are highly correlated, give similar results in prediction, but seem to differ in construct validity when compared to functional status depending on societal context or possibly birth cohort. Comparison of studies using different RTW definitions appears valid as long as RTW status is not considered as a measure of functional status.

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.

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…

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.

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.

Phootprint - A Phobos sample return mission study

NASA Astrophysics Data System (ADS)

Koschny, Detlef; Svedhem, Håkan; Rebuffat, Denis

Introduction ESA is currently studying a mission to return a sample from Phobos, called Phootprint. This study is performed as part of ESA’s Mars Robotic Exploration Programme. Part of the mission goal is to prepare technology needed for a sample return mission from Mars itself; the mission should also have a strong scientific justification, which is described here. 1. Science goal The main science goal of this mission will be to Understand the formation of the Martian moons Phobos and put constraints on the evolution of the solar system. Currently, there are several possibilities for explaining the formation of the Martian moons: (a) co-formation with Mars (b) capture of objects coming close to Mars (c) Impact of a large body onto Mars and formation from the impact ejecta The main science goal of this mission is to find out which of the three scenarios is the most probable one. To do this, samples from Phobos would be returned to Earth and analyzed with extremely high precision in ground-based laboratories. An on-board payload is foreseen to provide information to put the sample into the necessary geological context. 2. Mission Spacecraft and payload will be based on experience gained from previous studies to Martian moons and asteroids. In particular the Marco Polo and MarcoPolo-R asteroid sample return mission studies performed at ESA were used as a starting point. Currently, industrial studies are ongoing. The initial starting assumption was to use a Soyuz launcher. Uunlike the initial Marco Polo and MarcoPolo-R studies to an asteroid, a transfer stage will be needed. Another main difference to an asteroid mission is the fact that the spacecraft actually orbits Mars, not Phobos or Deimos. It is possible to select a spacecraft orbit, which in a Phobos- or Deimos-centred reference system would give an ellipse around the moon. The following model payload is currently foreseen: - Wide Angle Camera, - Narrow Angle Camera, - Close-Up Camera, - Context camera for

Analysis of Chinese Donors’ Return Behavior

PubMed Central

Guo, Nan; Wang, Jingxing; Ness, Paul; Yao, Fuzhu; Dong, Xiangdong; Bi, Xinhong; Mei, Heili; Li, Julin; He, Weilan; Lu, Yunlai; Ma, Hongli; Wen, Xiuqiong; Huang, Mei; Wright, David J.; King, Melissa; High, Patrick; Nelson, Kenrad; Shan, Hua

2010-01-01

Background It is important to understand donor return behavior. Converting first time donors to become repeat donors is essential for maintaining an adequate blood supply. Methods Characteristics of 241,552 whole blood (WB) donations from first time (FT) and repeat (RPT) donors who donated in 2008 at the 5 blood centers in China were compared. A subset of 54,394 WB donors who donated between January 1 and March 31, 2008 were analyzed for their return behavior in 2008 following the index donation using logistic regression. Results Of all donations, 64% was from FT donors. Donors with self-reported previous donations tended to be male, older, married, donated larger volume (≥300mL), and were heavier in weight. Among donors who donated from January to March, 2008, 14% returned for subsequent WB donations by the end of 2008. The number of previous donations and blood collection location were the two strongest predictors for making subsequent donations. Donors with 1, 2–3 and more than 3 previous donations were 3.7, 5.7, and 11.0 times more likely to return than FT donors. Those who donated in a blood collection vehicle were 4 times more likely to return than those who donated at a blood center. Being female, younger and of a lower education level (≤ middle school) were positively associated with subsequent return blood donation during the follow-up period observed in this study. Conclusion Most of the Chinese blood supply is from first time donors. Strategies aimed at encouraging current donors to become repeat donors are needed. PMID:20849408

Reassessment of Planetary Protection Requirements for Mars Sample Return Missions

NASA Astrophysics Data System (ADS)

Smith, David; Race, Margaret; Farmer, Jack

In 2008, NASA asked the US National Research Council (NRC) to review the findings of the report, Mars Sample Return: Issues and Recommendations (National Academy Press, 1997), and to update its recommendations in the light of both current understanding of Mars's biolog-ical potential and ongoing improvements in biological, chemical, and physical sample-analysis capabilities and technologies. The committee established to address this request was tasked to pay particular attention to five topics. First, the likelihood that living entities may be included in samples returned from Mars. Second, scientific investigations that should be conducted to reduce uncertainty in the assessment of Mars' biological potential. Third, the possibility of large-scale effects on Earth's environment if any returned entity is released into the environment. Fourth, the status of technological measures that could be taken on a mission to prevent the inadvertent release of a returned sample into Earth's biosphere. Fifth, criteria for intentional sample release, taking note of current and anticipated regulatory frameworks. The paper outlines the recommendations contained in the committee's final report, Planetary Protection Requirements for Mars Sample Return Missions (The National Academies Press, 2009), with particular emphasis placed on the scientific, technical and policy changes since 1997 and indications as to how these changes modify the recommendations contained in the 1997 report.

Comet flyby sample return

NASA Technical Reports Server (NTRS)

Tsou, P.; Albee, A.

1985-01-01

The results of a joint JPL/CSFC feasability study of a low-cost comet sample return flyby mission are presented. It is shown that the mission could be undertaken using current earth orbiter spacecraft technology in conjunction with pathfinder or beacon spacrcraft. Detailed scenarios of missions to the comets Honda-Mrkos-Pajdusakova (HMP), comet Kopff, and comet Giacobini-Zinner (GZ) are given, and some crossectional diagrams of the spacecraft designs are provided.

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.

Assured crew return capability Crew Emergency Return Vehicle (CERV) avionics

NASA Technical Reports Server (NTRS)

Myers, Harvey Dean

1990-01-01

The Crew Emergency Return Vehicle (CERV) is being defined to provide Assured Crew Return Capability (ACRC) for Space Station Freedom. The CERV, in providing the standby lifeboat capability, would remain in a dormat mode over long periods of time as would a lifeboat on a ship at sea. The vehicle must be simple, reliable, and constantly available to assure the crew's safety. The CERV must also provide this capability in a cost effective and affordable manner. The CERV Project philosophy of a simple vehicle is to maximize its useability by a physically deconditioned crew. The vehicle reliability goes unquestioned since, when needed, it is the vehicle of last resort. Therefore, its systems and subsystems must be simple, proven, state-of-the-art technology with sufficient redundancy to make it available for use as required for the life of the program. The CERV Project Phase 1'/2 Request for Proposal (RFP) is currently scheduled for release on October 2, 1989. The Phase 1'/2 effort will affirm the existing project requirements or amend and modify them based on a thorough evaluation of the contractor(s) recommendations. The system definition phase, Phase 2, will serve to define CERV systems and subsystems. The current CERV Project schedule has Phase 2 scheduled to begin October 1990. Since a firm CERV avionics design is not in place at this time, the treatment of the CERV avionics complement for the reference configuration is not intended to express a preference with regard to a system or subsystem.

Characteristics of inertial currents observed in offshore wave records

NASA Astrophysics Data System (ADS)

Gemmrich, J.; Garrett, C.

2012-04-01

It is well known that ambient currents can change the amplitude, direction and frequency of ocean surface waves. Regions with persistent strong currents, such as the Agulhas current off the east coast of South Africa, are known as areas of extreme waves, and wave height modulations of up to 50% observed in the shallow North Sea have been linked to tidal currents. In the open ocean, inertial currents, while intermittent, are typically the most energetic currents with speeds up to 0.5 m/s, and can interact with the surface wave field to create wave modulation, though this has not previously been reported. We use long records of significant wave heights from buoy observations in the northeast Pacific and show evidence of significant modulation at frequencies that are slightly higher than the local inertial frequency. Quite apart from the relevance to surface waves, this result can provide a consistent and independent measurement, over a wide range of latitudes, of the frequency blue-shift, the strength and intermittency of ocean surface inertial currents. Near-inertial waves constitute the most energetic portion of the internal wave band and play a significant role in deep ocean mixing. So far, observational data on near-surface inertial currents has tended to come from short records that do not permit the reliable determination of the frequency blue-shift, though this is an important factor affecting the energy flux from the surface into deeper waters. Long records from routine wave height observations are widely available and could help to shed new light globally on the blue-shift and on the characteristics of inertial currents.

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

Computing return times or return periods with rare event algorithms

NASA Astrophysics Data System (ADS)

Lestang, Thibault; Ragone, Francesco; Bréhier, Charles-Edouard; Herbert, Corentin; Bouchet, Freddy

2018-04-01

The average time between two occurrences of the same event, referred to as its return time (or return period), is a useful statistical concept for practical applications. For instance insurances or public agencies may be interested by the return time of a 10 m flood of the Seine river in Paris. However, due to their scarcity, reliably estimating return times for rare events is very difficult using either observational data or direct numerical simulations. For rare events, an estimator for return times can be built from the extrema of the observable on trajectory blocks. Here, we show that this estimator can be improved to remain accurate for return times of the order of the block size. More importantly, we show that this approach can be generalised to estimate return times from numerical algorithms specifically designed to sample rare events. So far those algorithms often compute probabilities, rather than return times. The approach we propose provides a computationally extremely efficient way to estimate numerically the return times of rare events for a dynamical system, gaining several orders of magnitude of computational costs. We illustrate the method on two kinds of observables, instantaneous and time-averaged, using two different rare event algorithms, for a simple stochastic process, the Ornstein–Uhlenbeck process. As an example of realistic applications to complex systems, we finally discuss extreme values of the drag on an object in a turbulent flow.

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

ACL Return to Sport Guidelines and Criteria.

PubMed

Davies, George J; McCarty, Eric; Provencher, Matthew; Manske, Robert C

2017-09-01

Because of the epidemiological incidence of anterior cruciate ligament (ACL) injuries, the high reinjury rates that occur when returning back to sports, the actual number of patients that return to the same premorbid level of competition, the high incidence of osteoarthritis at 5-10-year follow-ups, and the effects on the long-term health of the knee and the quality of life for the patient, individualizing the return to sports after ACL reconstruction (ACL-R) is critical. However, one of the challenging but unsolved dilemmas is what criteria and clinical decision making should be used to return an athlete back to sports following an ACL-R. This article describes an example of a functional testing algorithm (FTA) as one method for clinical decision making based on quantitative and qualitative testing and assessment utilized to make informed decisions to return an athlete to their sports safely and without compromised performance. The methods were a review of the best current evidence to support a FTA. In order to evaluate all the complicated domains of the clinical decision making for individualizing the return to sports after ACL-R, numerous assessments need to be performed including the biopsychosocial concepts, impairment testing, strength and power testing, functional testing, and patient-reported outcomes (PROs). The optimum criteria to use for individualizing the return to sports after ACL-R remain elusive. However, since this decision needs to be made on a regular basis with the safety and performance factors of the patient involved, this FTA provides one method of quantitatively and qualitatively making the decisions. Admittedly, there is no predictive validity of this system, but it does provide practical guidelines to facilitate the clinical decision making process for return to sports. The clinical decision to return an athlete back into competition has significant implications ranging from the safety of the athlete, to performance factors and actual

STARDUST and HAYABUSA: Sample Return Missions to Small Bodies in the Solar System

NASA Technical Reports Server (NTRS)

Sandford, S. A.

2005-01-01

There are currently two active spacecraft missions designed to return samples to Earth from small bodies in our Solar System. STARDUST will return samples from the comet Wild 2, and HAYABUSA will return samples from the asteroid Itokawa. On January 3,2004, the STARDUST spacecraft made the closest ever 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 will be returned to Earth on January 15,2006. After a brief preliminary examination to establish the nature of the returned samples, they will be made available to the general scientific community for study. The HAYABUSA spacecraft arrived at the Near Earth Asteroid Itokawa in September 2005 and is currently involved in taking remote sensing data from the asteroid. Several practice landings have been made and a sample collection landing will be made soon. The collected sample will be returned to Earth in June 2007. During my talk I will discuss the scientific goals of the STARDUST and HAYABUSA missions and provide an overview of their designs and flights to date. I will also show some of the exciting data returned by these spacecraft during their encounters with their target objects.

Submicrosecond risetimes in lightning return-stroke fields

NASA Technical Reports Server (NTRS)

Weidman, C. D.; Krider, E. P.

1980-01-01

Measurements of lightning electric field, E, and dE/dt signatures have been made near Tampa Bay, Florida, under conditions where the lightning locations were known and where the results were not significantly affected by the response time of the measuring system or groundwave propagation. The fast transitions found on the initial portion of return-stroke fields have 10-90% risetimes ranging from 40 to 200 nsec, with a mean of 90 nsec. The maximum field derivatives during return strokes range from 5 to 75 V/m per microsec with a mean of 29 V/m per microsec when normalized to a distance of 100 km. These field risetime and derivative values suggest that return-stroke currents contain large, submicrosecond components, and this in turn suggests that it may be necessary to reevaluate the possible effects of lightning and the performance of lightning-protection devices in many situations.

Radiation from lightning return strokes over a finitely conducting earth

NASA Technical Reports Server (NTRS)

Le Vine, D. M.; Gesell, L.; Kao, Michael

1986-01-01

The effects of the conductivity of the earth on radiation from lightning return strokes are examined theoretically using a piecewise linear transmission line model for the return stroke. First, calculations are made of the electric field radiated during the return stroke, and then this electric field is used to compute the response of conventional AM radio receivers and electric field change systems during the return stroke. The calculations apply to the entire transient waveform (they are not restricted to the initial portions of the return stroke) and yield fast field changes and RF radiation in agreement with measurements made during real lightning. This research was motivated by measurements indicating that a time delay exists between the time of arrival of the fast electric field change and the RF radiation from first return strokes. The time delay is on the order of 20 microsec for frequencies in the HF-UHF range for lightning in Florida. The time delay is obtained theoretically in this paper. It occurs when both the effects of attenuation due to conductivity of the earth, and the finite velocity of propagation of the current pulse up the return stroke channel, are taken into account in the model.

Phytoplankton Blooms Near the Cape of Good Hope

NASA Technical Reports Server (NTRS)

2002-01-01

Different phytoplankton communities color the ocean different shades of blue and green off the southern coast of South Africa in the December 22, 2000, Sea-viewing Wide Field-of-View Sensor (SeaWiFS) pass over the area. The convergence of two currents-the cold Benguela flowing North along the west coast of Africa, and a branch of the warm Agulhas heading west along the southern tip of the continent-causes upwelling cold, nutrient-rich water which feeds. The phytoplankton. The mixing cam also generate huge waves, making these waters very treacherous to sail. To learn more about the Benguela and Algulhas Currents, read A Clear Day Over the Agulhas Retroflection Image courtesy SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE

South Atlantic Ocean circulation: Simulation experiments with a quasi-geostrophic model and assimilation of TOPEX/POSEIDON and ERS 1 altimeter data

NASA Astrophysics Data System (ADS)

Florenchie, P.; Verron, J.

1998-10-01

Simulation experiments of South Atlantic Ocean circulations are conducted with a 1/6°, four-layered, quasi-geostrophic model. By means of a simple nudging data assimilation procedure along satellite tracks, TOPEX/POSEIDON and ERS 1 altimeter measurements are introduced into the model to control the simulation of the basin-scale circulation for the period from October 1992 to September 1994. The model circulation appears to be strongly influenced by the introduction of altimeter data, offering a consistent picture of South Atlantic Ocean circulations. Comparisons with observations show that the assimilating model successfully simulates the kinematic behavior of a large number of surface circulation components. The assimilation procedure enables us to produce schematic diagrams of South Atlantic circulation in which patterns ranging from basin-scale currents to mesoscale eddies are portrayed in a realistic way, with respect to their complexity. The major features of the South Atlantic circulation are described and analyzed, with special emphasis on the Brazil-Malvinas Confluence region, the Subtropical Gyre with the formation of frontal structures, and the Agulhas Retroflection. The Agulhas eddy-shedding process has been studied extensively. Fourteen eddies appear to be shed during the 2-year experiment. Because of their strong surface topographic signature, Agulhas eddies have been tracked continuously during the assimilation experiment as they cross the South Atlantic basin westward. Other effects of the assimilation procedure are shown, such as the intensification of the Subtropical Gyre, the appearance of a strong seasonal cycle in the Brazil Current transport, and the increase of the mean Brazil Current transport. This last result, combined with the westward oriention of the Agulhas eddies' trajectories, leads to a southward transport of mean eddy kinetic energy across 30°S.

Mars Sample Return mission utilizing in-situ propellant production

NASA Technical Reports Server (NTRS)

Zubrin, Robert; Price, Steve

1995-01-01

This report presents the results of a study examining the potential of in-situ propellant production (ISPP) on Mars to aid in achieving a low cost Mars Sample Return (MSR) mission. Two versions of such a mission were examined: a baseline version employing a dual string spacecraft, and a light weight version employing single string architecture with selective redundancy. Both systems employed light weight avionics currently being developed by Lockheed Martin, Jet Propulsion Lab and elsewhere in the aerospace community, both used a new concept for a simple, light weight parachuteless sample return capsule, both used a slightly modified version of the Mars Surveyor lander currently under development at Lockheed Martin for flight in 1998, and both used a combination of the Sabatier-electrolysis and reverse water gas shift ISPP systems to produce methane/oxygen propellant on Mars by combining a small quantity of imported hydrogen with the Martian CO2 atmosphere. It was found that the baseline mission could be launched on a Delta 7925 and return a 0.5 kg sample with 82 percent mission launch margin;over and beyond subsystem allocated contingency masses . The lightweight version could be launched on a Mid-Lite vehicle and return a 0.25 kg sample with 11 percent launch margin, over and above subsystem contingency mass allocations.

Premature return to play and return to learn after a sport-related concussion

PubMed Central

Carson, James D.; Lawrence, David W.; Kraft, Sari A.; Garel, Alisha; Snow, Catherine L.; Chatterjee, Ananda; Libfeld, Paula; MacKenzie, Heather M.; Thornton, Jane S.; Moineddin, Rahim; Frémont, Pierre

2014-01-01

days of rest before being permitted to return to any physical activity compared with high school students and college or university students. Conclusion Currently, physicians recommend restrictions on mental and physical activity following sport-related concussion. This is done without clear guidelines as to what cognitive rest entails for students. Further research is required to determine how to implement a management plan for student athletes to facilitate complete recovery after concussion. PMID:24925965

The Mars Sample Return Project

NASA Technical Reports Server (NTRS)

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. c 2000 American Institute of Aeronautics and Astronautics, Inc. Published by Elsevier Science Ltd.

Accelerated Return to Sport After Osteochondral Autograft Plug Transfer

PubMed Central

Werner, Brian C.; Cosgrove, Chris T.; Gilmore, C. Jan; Lyons, Matthew L.; Miller, Mark D.; Brockmeier, Stephen F.; Diduch, David R.

2017-01-01

Background: Previous studies have reported varying return-to-sport protocols after knee cartilage restoration procedures. Purpose: To (1) evaluate the time for return to sport in athletes with an isolated chondral injury who underwent an accelerated return-to-sport protocol after osteochondral autograft plug transfer (OAT) and (2) evaluate clinical outcomes to assess for any consequences from the accelerated return to sport. Study Design: Case series; Level of evidence, 4. Methods: An institutional cohort of 152 OAT procedures was reviewed, of which 20 competitive athletes met inclusion and exclusion criteria. All patients underwent a physician-directed accelerated rehabilitation program after their procedure. Return to sport was determined for all athletes. Clinical outcomes were assessed using International Knee Documentation Committee (IKDC) and Tegner scores as well as assessment of level of participation on return to sport. Results: Return-to-sport data were available for all 20 athletes; 13 of 20 athletes (65%) were available for clinical evaluation at a mean 4.4-year follow-up. The mean time for return to sport for all 20 athletes was 82.9 ± 25 days (range, 38-134 days). All athletes were able to return to sport at their previous level and reported that they were satisfied or very satisfied with their surgical outcome and ability to return to sport. The mean postoperative IKDC score was 84.5 ± 9.5. The mean Tegner score prior to injury was 8.9 ± 1.7; it was 7.7 ± 1.9 at final follow-up. Conclusion: Competitive athletes with traumatic chondral defects treated with OAT managed using this protocol had reduced time to preinjury activity levels compared with what is currently reported, with excellent clinical outcomes and no serious long-term sequelae. PMID:28451623

49 CFR 1152.34 - Return on investment.

Code of Federal Regulations, 2014 CFR

2014-10-01

... TRANSPORTATION UNDER 49 U.S.C. 10903 Standards for Determining Costs, Revenues, and Return on Value § 1152.34...). (ii) The amount of current income tax benefits resulting from abandonment of the line which would have... income tax liability from abandonment, the liability should be deducted from the investment base.) This...

49 CFR 1152.34 - Return on investment.

Code of Federal Regulations, 2013 CFR

2013-10-01

... TRANSPORTATION UNDER 49 U.S.C. 10903 Standards for Determining Costs, Revenues, and Return on Value § 1152.34...). (ii) The amount of current income tax benefits resulting from abandonment of the line which would have... income tax liability from abandonment, the liability should be deducted from the investment base.) This...

49 CFR 1152.34 - Return on investment.

Code of Federal Regulations, 2012 CFR

2012-10-01

... TRANSPORTATION UNDER 49 U.S.C. 10903 Standards for Determining Costs, Revenues, and Return on Value § 1152.34...). (ii) The amount of current income tax benefits resulting from abandonment of the line which would have... income tax liability from abandonment, the liability should be deducted from the investment base.) This...

Vigorous exchange between the Indian and Atlantic oceans at the end of the past five glacial periods.

PubMed

Peeters, Frank J C; Acheson, Ruth; Brummer, Geert-Jan A; De Ruijter, Wilhelmus P M; Schneider, Ralph R; Ganssen, Gerald M; Ufkes, Els; Kroon, Dick

2004-08-05

The magnitude of heat and salt transfer between the Indian and Atlantic oceans through 'Agulhas leakage' is considered important for balancing the global thermohaline circulation. Increases or reductions of this leakage lead to strengthening or weakening of the Atlantic meridional overturning and associated variation of North Atlantic Deep Water formation. Here we show that modern Agulhas waters, which migrate into the south Atlantic Ocean in the form of an Agulhas ring, contain a characteristic assemblage of planktic foraminifera. We use this assemblage as a modern analogue to investigate the Agulhas leakage history over the past 550,000 years from a sediment record in the Cape basin. Our reconstruction indicates that Indian-Atlantic water exchange was highly variable: enhanced during present and past interglacials and largely reduced during glacial intervals. Coherent variability of Agulhas leakage with northern summer insolation suggests a teleconnection to the monsoon system. The onset of increased Agulhas leakage during late glacial conditions took place when glacial ice volume was maximal, suggesting a crucial role for Agulhas leakage in glacial terminations, timing of interhemispheric climate change and the resulting resumption of the Atlantic meridional overturning circulation.

Return to Sport After Tibial Shaft Fractures

PubMed Central

Robertson, Greg A. J.; Wood, Alexander M.

2015-01-01

Context: Acute tibial shaft fractures represent one of the most severe injuries in sports. Return rates and return-to-sport times after these injuries are limited, particularly with regard to the outcomes of different treatment methods. Objective: To determine the current evidence for the treatment of and return to sport after tibial shaft fractures. Data Sources: OVID/MEDLINE (PubMed), EMBASE, CINAHL, Cochrane Collaboration Database, Web of Science, PEDro, SPORTDiscus, Scopus, and Google Scholar were all searched for articles published from 1988 to 2014. Study Selection: Inclusion criteria comprised studies of level 1 to 4 evidence, written in the English language, that reported on the management and outcome of tibial shaft fractures and included data on either return-to-sport rate or time. Studies that failed to report on sporting outcomes, those of level 5 evidence, and those in non–English language were excluded. Study Design: Systematic review. Level of Evidence: Level 4. Data Extraction: The search used combinations of the terms tibial, tibia, acute, fracture, athletes, sports, nonoperative, conservative, operative, and return to sport. Two authors independently reviewed the selected articles and created separate data sets, which were subsequently combined for final analysis. Results: A total of 16 studies (10 retrospective, 3 prospective, 3 randomized controlled trials) were included (n = 889 patients). Seventy-six percent (672/889) of the patients were men, with a mean age of 27.7 years. Surgical management was assessed in 14 studies, and nonsurgical management was assessed in 8 studies. Return to sport ranged from 12 to 54 weeks after surgical intervention and from 28 to 182 weeks after nonsurgical management (mean difference, 69.5 weeks; 95% CI, –83.36 to −55.64; P < 0.01). Fractures treated surgically had a return-to-sport rate of 92%, whereas those treated nonsurgically had a return rate of 67% (risk ratio, 1.37; 95% CI, 1.20 to 1.57; P < 0

Return-to-Work Program for Injured Workers: Factors of Successful Return to Employment.

PubMed

Awang, Halimah; Shahabudin, Sharifah Muhairah; Mansor, Norma

2016-11-01

This study examined the factors of successful return to employment among participants in the return to work program (RTW) following work-related injury. Data were obtained from the Social Security Organization database containing 9850 injured workers who underwent RTW in 2010 to 2013. About 65% had successfully returned to employment. Significant factors of successful return include gender, employer interest, motivation, age, intervention duration, and type of injury. Male and motivated employees were more likely to return to employment compared with female and unmotivated employees, respectively. Participants from interested employers were 23.22 times more likely to return to work than those from uninterested employers, whereas participants whose intervention period exceeded 5 months were 41% less likely to return to work compared with those whose intervention period was within 3 months. Appropriate strategy and enhanced collaboration between the stakeholders would improve the proportion of successful return to employment. © 2016 APJPH.

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…

Reconstructing dust fluxes and paleoproductivity at the southern Agulhas Plateau since MIS-6

NASA Astrophysics Data System (ADS)

Frenkel, M. M.; Anderson, R. F.; Winckler, G.

2017-12-01

Understanding the mechanisms underlying glacial-interglacial cycles requires characterizing the role of oceanic feedbacks in climatic changes. For example, increased aeolian iron fluxes to Fe-limited regions of the ocean and corresponding changes in marine productivity could have improved biological pump efficiency and resulted in CO2 drawdown. Here we explore these feedbacks using marine sediment core MDO2-2588 collected from the southern Agulhas Plateau (SAP; 41°S, 26°E), located beneath the modern subtropical front. Today, diatom productivity in this region is Si-limited because high Si utilization south of the polar front (PF) means that water advected northward to our study site is Si-depleted. However, previous work has suggested that extended sea ice cover during glacial periods may have limited diatom productivity south of the PF while frontal systems shifted northward, allowing more Si to reach thermocline of the SAP. Meanwhile, increased glacial dust flux to the SAP may have simultaneously supplied more Fe, contributing to higher glacial productivity. This hypothesis has been supported by observations of higher LGM and MIS-6 productivity at MD02-2588 using bulk biogenic content and diatom assemblages (Romero et al., Paleoceanography, 30 (2015) 118-132). Gradients in d13C between benthic and planktic foraminifera have also been used to support Fe fertilization at this site on millennial timescales (Ziegler et al., Nature Geoscience, 6 (2013) 457-461). Yet, studies have yet to produce coordinated records of dust flux and export production for the SAP. Here, we present records of dust, based on 230Th-normalized 232Th fluxes, and export production using 230Th-normalized excess-Ba and opal fluxes and authigenic U through MIS-6. Preliminary results show that lithogenic fluxes to MD02-2588 were approximately twice as high during MIS-6 as MIS-5e and were concurrent with a two-fold increase in excess-Ba flux. However, this relative increase in lithogenic flux

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

Code of Federal Regulations, 2010 CFR

2010-04-01

... the case of a joint return made under section 6013(b), the period of limitations provided in sections... (c)(1) of this section, relating to the application of sections 6501 and 6651 with respect to a joint... 26 Internal Revenue 13 2010-04-01 2010-04-01 false Joint return after filing separate return. 1...

Return to sports after ankle fractures: a systematic review.

PubMed

Del Buono, Angelo; Smith, Rebecca; Coco, Manuela; Woolley, Laurence; Denaro, Vincenzo; Maffulli, Nicola

2013-01-01

This review aims to provide information on the time athletes will take to resume sports activity following ankle fractures. We systematically searched Medline (PubMED), EMBASE, CINHAL, Cochrane, Sports Discus and Google scholar databases using the combined keywords 'ankle fractures', 'ankle injuries', 'athletes', 'sports', 'return to sport', 'recovery', 'operative fixation', 'pinning', 'return to activity' to identify articles published in English, Spanish, French, Portuguese and Italian. Seven retrospective studies fulfilled our inclusion criteria. Of the 793 patients, 469 (59%) were males and 324 (41%) were females, and of the 356 ankle fractures we obtained information on, 338 were acute and 18 stress fractures. The general principles were to undertake open reduction and internal fixation of acute fractures, and manage stress fractures conservatively unless a thin fracture line was visible on radiographs. The best timing to return to sports after an acute ankle fracture is still undefined, given the heterogeneity of the outcome measures and results. The time to return to sports after an acute stress injury ranged from 3 to 51 weeks. When facing athletes with ankle fractures, associated injuries have to be assessed and addressed to improve current treatment lines and satisfy future expectancies. The best timing to return to sports after an ankle fracture has not been established yet. The ideas of the return to activity parameter and surgeon databases including sports-related information could induce research to progress.

"I never made it to the pros…" Return to sport and becoming an elite athlete after pediatric and adolescent anterior cruciate ligament injury-Current evidence and future directions.

PubMed

Hamrin Senorski, Eric; Seil, Romain; Svantesson, Eleonor; Feller, Julian A; Webster, Kate E; Engebretsen, Lars; Spindler, Kurt; Siebold, Rainer; Karlsson, Jón; Samuelsson, Kristian

2018-04-01

The management of anterior cruciate ligament (ACL) injuries in the skeletally immature and adolescent patient remains an area of controversy in sports medicine. This study, therefore, summarizes and discusses the current evidence related to treating pediatric and adolescent patients who sustain an ACL injury. The current literature identifies a trend towards ACL reconstruction as the preferred treatment option for ACL injuries in the young, largely justified by the risk of further structural damage to the knee joint. Worryingly, a second ACL injury is all too common in the younger population, where almost one in every three to four young patients who sustain an ACL injury and return to high-risk pivoting sport will go on to sustain another ACL injury. The clinical experience of these patients emphasizes the rarity of an athlete who makes it to elite level after a pediatric or adolescent ACL injury, with or without reconstruction. If these patients are unable to make it to an elite level of sport, treatment should possibly be modified to take account of the risks associated with returning to pivoting and strenuous sport. The surveillance of young athletes may be beneficial when it comes to reducing injuries. Further research is crucial to better understand specific risk factors in the young and to establish independent structures to allow for unbiased decision-making for a safe return to sport after ACL injury. Level of evidence V.

Biological Sterilization of Returned Mars Samples

NASA Technical Reports Server (NTRS)

Allen, C. C.; Albert, F. G.; Combie, J.; Bodnar, R. J.; Hamilton, V. E.; Jolliff, B. L.; Kuebler, K.; Wang, A.; Lindstrom, D. J.; Morris, P. A.

1999-01-01

Martian rock and soil, collected by robotic spacecraft, will be returned to terrestrial laboratories early in the next century. Current plans call for the samples to be immediately placed into biological containment and tested for signs of present or past life and biological hazards. It is recommended that "Controlled distribution of unsterilized materials from Mars should occur only if rigorous analyses determine that the materials do not constitute a biological hazard. If any portion of the sample is removed from containment prior to completion of these analyses it should first be sterilized." While sterilization of Mars samples may not be required, an acceptable method must be available before the samples are returned to Earth. The sterilization method should be capable of destroying a wide range of organisms with minimal effects on the geologic samples. A variety of biological sterilization techniques and materials are currently in use, including dry heat, high pressure steam, gases, plasmas and ionizing radiation. Gamma radiation is routinely used to inactivate viruses and destroy bacteria in medical research. Many commercial sterilizers use Co-60 , which emits gamma photons of 1.17 and 1.33 MeV. Absorbed doses of approximately 1 Mrad (10(exp 8) ergs/g) destroy most bacteria. This study investigates the effects of lethal doses of Co-60 gamma radiation on materials similar to those anticipated to be returned from Mars. The goals are to determine the gamma dose required to kill microorganisms in rock and soil samples and to determine the effects of gamma sterilization on the samples' isotopic, chemical and physical properties. Additional information is contained in the original extended abstract.

Properties of M components from currents measured at triggered lightning channel base

NASA Astrophysics Data System (ADS)

Thottappillil, Rajeev; Goldberg, Jon D.; Rakov, Vladimir A.; Uman, Martin A.; Fisher, Richard J.; Schnetzer, George H.

1995-12-01

Channel base currents from triggered lightning were measured at the NASA Kennedy Space Center, Florida, during summer 1990 and at Fort McClellan, Alabama, during summer 1991. An analysis of the return stroke data and overall continuing current data has been published by Fisher et al. [1993]. Here an analysis is given of the impulsive processes, called M components, that occur during the continuing current following return strokes. The 14 flashes analyzed contain 37 leader-return stroke sequences and 158 M components, both processes lowering negative charge from cloud to ground. Statistics are presented for the following M current pulse parameters: magnitude, rise time, duration, half-peak width, preceding continuing current level, M interval, elapsed time since the return stroke, and charge transferred by the M current pulse. A typical M component in triggered lightning is characterized by a more or less symmetrical current pulse having an amplitude of 100-200 A (2 orders of magnitude lower than that for a typical return stroke [Fisher et al., 1993]), a 10-90% rise time of 300-500 μs (3 orders of magnitude larger than that for a typical return stroke [Fisher et al., 1993]), and a charge transfer to ground of the order of 0.1 to 0.2 C (1 order of magnitude smaller than that for a typical subsequent return stroke pulse [Berger et al., 1975]). About one third of M components transferred charge greater than the minimum charge reported by Berger et al. [1975] for subsequent leader-return stroke sequences. No correlation was found between either the M charge or the magnitude of the M component current (the two are moderately correlated) and any other parameter considered. M current pulses occurring soon after the return stroke tend to have shorter rise times, shorter durations, and shorter M intervals than those which occur later. M current pulses were observed to be superimposed on continuing currents greater than 30 A or so, with one exception out of 140 cases

Investigating the role of capacitive coupling between the operating table and the return electrode of an electrosurgery unit in the modification of the current density distribution within the patients' body.

PubMed

Bifulco, Paolo; Massa, Rita; Cesarelli, Mario; Romano, Maria; Fratini, Antonio; Gargiulo, Gaetano D; McEwan, Alistair L

2013-08-12

Electrosurgery units are widely employed in modern surgery. Advances in technology have enhanced the safety of these devices, nevertheless, accidental burns are still regularly reported. This study focuses on possible causes of sacral burns as complication of the use of electrosurgery. Burns are caused by local densifications of the current, but the actual pathway of current within patient's body is unknown. Numerical electromagnetic analysis can help in understanding the issue. To this aim, an accurate heterogeneous model of human body (including seventy-seven different tissues), electrosurgery electrodes, operating table and mattress was build to resemble a typical surgery condition. The patient lays supine on the mattress with the active electrode placed onto the thorax and the return electrode on his back. Common operating frequencies of electrosurgery units were considered. Finite Difference Time Domain electromagnetic analysis was carried out to compute the spatial distribution of current density within the patient's body. A differential analysis by changing the electrical properties of the operating table from a conductor to an insulator was also performed. Results revealed that distributed capacitive coupling between patient body and the conductive operating table offers an alternative path to the electrosurgery current. The patient's anatomy, the positioning and the different electromagnetic properties of tissues promote a densification of the current at the head and sacral region. In particular, high values of current density were located behind the sacral bone and beneath the skin. This did not occur in the case of non-conductive operating table. Results of the simulation highlight the role played from capacitive couplings between the return electrode and the conductive operating table. The concentration of current density may result in an undesired rise in temperature, originating burns in body region far from the electrodes. This outcome is concordant

Controlling hollow relativistic electron beam orbits with an inductive current divider

DOE PAGES

Swanekamp, S. B.; Richardson, A. S.; Angus, J. R.; ...

2015-02-06

A passive method for controlling the trajectory of an intense, hollow electron beam is proposed using a vacuum structure that inductively splits the beam's return current. A central post carries a portion of the return current (I 1), while the outer conductor carries the remainder (I 2). An envelope equation appropriate for a hollow electron beam is derived and applied to the current divider. The force on the beam trajectory is shown to be proportional to (I 2-I 1), while the average force on the envelope (the beam width) is proportional to the beam current I b = (I 2more » + I 1). The values of I 1 and I 2 depend on the inductances in the return-current path geometries. Proper choice of the return-current geometries determines these inductances and offers control over the beam trajectory. As a result, solutions using realistic beam parameters show that, for appropriate choices of the return-current-path geometry, the inductive current divider can produce a beam that is both pinched and straightened so that it approaches a target at near-normal incidence with a beam diameter that is on the order of a few mm.« less

Long-Term Geomagnetically Induced Current Observations From New Zealand: Peak Current Estimates for Extreme Geomagnetic Storms

NASA Astrophysics Data System (ADS)

Rodger, Craig J.; Mac Manus, Daniel H.; Dalzell, Michael; Thomson, Alan W. P.; Clarke, Ellen; Petersen, Tanja; Clilverd, Mark A.; Divett, Tim

2017-11-01

Geomagnetically induced current (GIC) observations made in New Zealand over 14 years show induction effects associated with a rapidly varying horizontal magnetic field (dBH/dt) during geomagnetic storms. This study analyzes the GIC observations in order to estimate the impact of extreme storms as a hazard to the power system in New Zealand. Analysis is undertaken of GIC in transformer number six in Islington, Christchurch (ISL M6), which had the highest observed currents during the 6 November 2001 storm. Using previously published values of 3,000 nT/min as a representation of an extreme storm with 100 year return period, induced currents of 455 A were estimated for Islington (with the 95% confidence interval range being 155-605 A). For 200 year return periods using 5,000 nT/min, current estimates reach 755 A (confidence interval range 155-910 A). GIC measurements from the much shorter data set collected at transformer number 4 in Halfway Bush, Dunedin, (HWB T4), found induced currents to be consistently a factor of 3 higher than at Islington, suggesting equivalent extreme storm effects of 460-1,815 A (100 year return) and 460-2,720 A (200 year return). An estimate was undertaken of likely failure levels for single-phase transformers, such as HWB T4 when it failed during the 6 November 2001 geomagnetic storm, identifying that induced currents of 100 A can put such transformer types at risk of damage. Detailed modeling of the New Zealand power system is therefore required to put this regional analysis into a global context.

Premature return to play and return to learn after a sport-related concussion: physician's chart review.

PubMed

Carson, James D; Lawrence, David W; Kraft, Sari A; Garel, Alisha; Snow, Catherine L; Chatterjee, Ananda; Libfeld, Paula; MacKenzie, Heather M; Thornton, Jane S; Moineddin, Rahim; Frémont, Pierre

2014-06-01

To determine what proportion of patients experience an exacerbation of their symptoms as a result of premature return to play (RTP) and return to learn (RTL) following sport-related concussions. Retrospective study of electronic medical records from the office-based practice of one family and sport medicine physician who had systematically provided recommendations for cognitive and physical rest based on existing consensus recommendations. Two blinded authors independently reviewed each chart, which included Sport Concussion Assessment Tool (SCAT) and SCAT2 symptom self-report forms to determine whether an athlete had returned to play or learn prematurely. If there was a discrepancy between the 2 reviewers then a third author reviewed the charts. A sport medicine and family practice in Ontario. The physician assessed sport-related concussions after self-referral or referral from other primary care physicians, teams, and schools. A total of 170 charts of 159 patients were assessed for sport-related concussion during a 5-year period (April 2006 to March 2011). All participants were students who were participating in sports at the time of injury. There were 41 concussions in elementary students, 95 concussions in high school students, and 34 concussions in college or university students. Premature RTP and RTL were defined as chart records documenting the recurrence or worsening of symptoms that accompanied the patients' RTP or RTL. Measures were compared using the earliest available SCAT forms and self-reporting. In 43.5% of concussion cases, the patient returned to sport too soon and in 44.7% of concussion cases, the patient returned to school too soon. Patients with a history of previous concussion required more days of rest before being permitted to participate in any physical activity than those patients without a previous history of concussion. Elementary school students required fewer days of rest before being permitted to return to any physical activity

Review of X-43A Return to Flight Activities and Current Status

NASA Technical Reports Server (NTRS)

Reubush, David E.; Nguyen, Luat T.; Rausch, Vincent L.

2004-01-01

This paper provides an overview and status of the return to flight activities for the X-43A scramjet flight demonstrator after the first flight mishap. The first flight was attempted on June 2, 2001 and resulted in vehicle destruction by range safety when the booster went out of control early in the flight. In the time since the mishap much work has been done to examine the causes of the failure and make modifications to the booster to insure that the boost for the second flight will be successful. In addition, all other aspects of the flight have been examined to maximize the probability of a successful flight.

30 CFR 57.22215 - Separation of intake and return air (I-A, II-A, III, and V-A mines).

Code of Federal Regulations, 2010 CFR

2010-07-01

... Separation of intake and return air (I-A, II-A, III, and V-A mines). Main intake and return air currents... for separation of air currents. Such wall or partition shall be constructed of reinforced concrete or... separation of main air currents in the same opening. Flexible ventilation tubing shall not exceed 250 feet in...

30 CFR 57.22215 - Separation of intake and return air (I-A, II-A, III, and V-A mines).

Code of Federal Regulations, 2011 CFR

2011-07-01

... Separation of intake and return air (I-A, II-A, III, and V-A mines). Main intake and return air currents... for separation of air currents. Such wall or partition shall be constructed of reinforced concrete or... separation of main air currents in the same opening. Flexible ventilation tubing shall not exceed 250 feet in...

NASA needs a long-term sample return strategy

NASA Astrophysics Data System (ADS)

Agee, C.

Sample return missions, as demonstrated by Apollo, can have a huge payoff for plan- etary science. Beyond NASAAfs current Discovery missions, Stardust and Genesis, there are no future U.S. sample return missions on the books. At this juncture, it would be desirable for NASA to develop a coherent, long-term strategy for sample return missions to prime targets such as Mars, Venus, and other solar system bodies. The roster of missions planned for this decade in NASAAfs Mars Program no longer includes a sample return. Arguments against an early Mars sample return (MSR) in- clude the high cost, high risk, and not knowing the Agright placeAh on the Martian surface to sample. On the other hand, answering many of the key scientific questions about Mars, including the search for life, may require sample return. In lieu of MSR, NASA plans, out to 2009, a mix of orbital and landed missions that will perform re- mote and in-situ science at Mars. One approach to MSR that may lead to success in the opportunities beyond 2009 is a series of simple missions where large rovers and complex instruments are replaced by robust Mars ascent vehicles and lander-based sampling techniques. AgMobilityAh and Agsample diversityAh in these early reconnaissance sample return missions are accomplished by sending each mission to a distinctly different location based on our understanding of Martian geology prior to launch. The expected wealth of knowledge from these simple sample return missions will help guide Mars exploration beyond 2020. Venus sample return (VSR) should also be a high priority in NASAAfs exploration of the solar system. Our understanding of the Venusian surface is fragmentary at best and the mineralogy in unknown. We have no verified meteorites from Venus and thus radiometric ages of the crust do not exist. Venusian science best done on Earth from a VSR would include (1) precise isotopic measurements of atmospheric gases, soil, and rock, (2) age dating of rock, (3) trace element

Controlling hollow relativistic electron beam orbits with an inductive current divider

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

Swanekamp, S. B.; Richardson, A. S.; Angus, J. R.

2015-02-15

A passive method for controlling the trajectory of an intense, hollow electron beam is proposed using a vacuum structure that inductively splits the beam's return current. A central post carries a portion of the return current (I{sub 1}), while the outer conductor carries the remainder (I{sub 2}). An envelope equation appropriate for a hollow electron beam is derived and applied to the current divider. The force on the beam trajectory is shown to be proportional to (I{sub 2}-I{sub 1}), while the average force on the envelope (the beam width) is proportional to the beam current I{sub b} = (I{sub 2} + I{sub 1}). Themore » values of I{sub 1} and I{sub 2} depend on the inductances in the return-current path geometries. Proper choice of the return-current geometries determines these inductances and offers control over the beam trajectory. Solutions using realistic beam parameters show that, for appropriate choices of the return-current-path geometry, the inductive current divider can produce a beam that is both pinched and straightened so that it approaches a target at near-normal incidence with a beam diameter that is on the order of a few mm.« less

Current-limited electron beam injection

NASA Technical Reports Server (NTRS)

Stenzel, R. L.

1977-01-01

The injection of an electron beam into a weakly collisional, magnetized background plasma was investigated experimentally. The injected beam was energetic and cold, the background plasma was initially isothermal. Beam and plasma dimensions were so large that the system was considered unbounded. The temporal and spatial evolution of the beam-plasma system was dominated by collective effects. High-frequency electrostatic instabilities rapidly thermalized the beam and heated the background electrons. The injected beam current was balanced by a return current consisting of background electrons drifting toward the beam source. The drift between electrons and ions gave rise to an ion acoustic instability which developed into strong three-dimensional turbulence. It was shown that the injected beam current was limited by the return current which is approximately given by the electron saturation current. Non-Maxwellian electron distribution functions were observed.

OHB's Exploration Capabilities Overview Relevant to Mars Sample Return Mission

NASA Astrophysics Data System (ADS)

Jaime, A.; Gerth, I.; Rohrbeck, M.; Scheper, M.

2018-04-01

The presentation will give an overview to all the OHB past and current projects that are relevant to the Mars Sample Return (MSR) mission, including some valuable lessons learned applicable to the upcoming MSR mission.

Workers' Compensation, Return to Work, and Lumbar Fusion for Spondylolisthesis.

PubMed

Anderson, Joshua T; Haas, Arnold R; Percy, Rick; Woods, Stephen T; Ahn, Uri M; Ahn, Nicholas U

2016-01-01

Lumbar fusion for spondylolisthesis is associated with consistent outcomes in the general population. However, workers' compensation is a risk factor for worse outcomes. Few studies have evaluated prognostic factors within this clinically distinct population. The goal of this study was to identify prognostic factors for return to work among patients with workers' compensation claims after fusion for spondylolisthesis. The authors used International Classification of Diseases, Ninth Revision, and Current Procedural Terminology codes to identify 686 subjects from the Ohio Bureau of Workers' Compensation who underwent fusion for spondylolisthesis from 1993 to 2013. Positive return to work status was recorded in patients who returned to work within 2 years of fusion and remained working for longer than 6 months. The criteria for return to work were met by 29.9% (n=205) of subjects. The authors used multivariate logistic regression analysis to identify prognostic factors for return to work. Negative preoperative prognostic factors for postoperative return to work included: out of work for longer than 1 year before fusion (P<.001; odds ratio [OR], 0.16); depression (P=.007; OR<0.01); long-term opioid analgesic use (P=.006; OR, 0.41); lumbar stenosis (P=.043; OR, 0.55); and legal representation (P=.042; OR, 0.63). Return to work rates associated with these factors were 9.7%, 0.0%, 10.0%, 29.2%, and 25.0%, respectively. If these subjects were excluded, the return to work rate increased to 60.4%. The 70.1% (n=481) of subjects who did not return to work had markedly worse outcomes, shown by higher medical costs, chronic opioid dependence, and higher rates of failed back syndrome, total disability, and additional surgery. Psychiatric comorbidity increased after fusion but was much higher in those who did not return to work. Future studies are needed to identify how to better facilitate return to work among similar patients with workers' compensation claims. Copyright 2016

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, DESTRUCTIVE...

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, DESTRUCTIVE...

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, DESTRUCTIVE...

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, DESTRUCTIVE...

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, DESTRUCTIVE...

Small scale currents and ocean wave heights: from today's models to future satellite observations with CFOSAT and SKIM

NASA Astrophysics Data System (ADS)

Ardhuin, Fabrice; Gille, Sarah; Menemenlis, Dimitris; Rocha, Cesar; Rascle, Nicolas; Gula, Jonathan; Chapron, Bertrand

2017-04-01

Tidal currents and large oceanic currents, such as the Agulhas, Gulf Stream and Kuroshio, are known to modify ocean wave properties, causing extreme sea states that are a hazard to navigation. Recent advances in the understanding and modeling capability of ocean currents at scales of 10 km or less have revealed the ubiquitous presence of fronts and filaments. Based on realistic numerical models, we show that these structures can be the main source of variability in significant wave heights at scales less than 200 km, including important variations at 10 km. This current-induced variability creates gradients in wave heights that were previously overlooked and are relevant for extreme wave heights and remote sensing. The spectrum of significant wave heights is found to be of the order of 70⟨Hs ⟩2/(g2⟨Tm0,-1⟩2) times the current spectrum, where ⟨Hs ⟩ is the spatially-averaged significant wave height, ⟨Tm0,-1⟩ is the average energy period, and g is the gravity acceleration. This small scale variability is consistent with Jason-3 and SARAL along-track variability. We will discuss how future satellite mission with wave spectrometers can help observe these wave-current interactions. CFOSAT is due for launch in 2018, and SKIM is a proposal for ESA Earth Explorer 9.

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…

Does a Syrinx Matter for Return to Play in Contact Sports? A Case Report and Evidence-Based Review of Return-to-Play Criteria After Transient Quadriplegia.

PubMed

Milles, Jeffrey L; Gallizzi, Michael A; Sherman, Seth L; Smith, Patrick A; Choma, Theodore J

2014-09-01

Transient quadriplegia is a rare injury that can change the course of an athlete's career if misdiagnosed or managed inappropriately. The clinician should be well versed in the return-to-play criteria for this type of injury. Unfortunately, when an unknown preexisting syrinx is present in the athlete, there is less guidance on their ability to return to play. This case report and review of the current literature illustrates a National Collegiate Athletic Association (NCAA) Division I football player who suffered a transient quadriplegic event during a kickoff return that subsequently was found to have an incidental cervical syrinx on magnetic resonance imaging. The player was able to have a full neurologic recovery, but ultimately he was withheld from football.

Does a Syrinx Matter for Return to Play in Contact Sports? A Case Report and Evidence-Based Review of Return-to-Play Criteria After Transient Quadriplegia

PubMed Central

Milles, Jeffrey L.; Gallizzi, Michael A.; Sherman, Seth L.; Smith, Patrick A.; Choma, Theodore J.

2014-01-01

Transient quadriplegia is a rare injury that can change the course of an athlete’s career if misdiagnosed or managed inappropriately. The clinician should be well versed in the return-to-play criteria for this type of injury. Unfortunately, when an unknown preexisting syrinx is present in the athlete, there is less guidance on their ability to return to play. This case report and review of the current literature illustrates a National Collegiate Athletic Association (NCAA) Division I football player who suffered a transient quadriplegic event during a kickoff return that subsequently was found to have an incidental cervical syrinx on magnetic resonance imaging. The player was able to have a full neurologic recovery, but ultimately he was withheld from football. PMID:25177422

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

75 FR 75439 - Specified Tax Return Preparers Required To File Individual Income Tax Returns Using Magnetic Media

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-03

... 1545-BJ52 Specified Tax Return Preparers Required To File Individual Income Tax Returns Using Magnetic... for ``specified tax return preparers,'' generally tax return preparers who reasonably expect to file more than 10 individual income tax returns in a calendar year, to file individual income tax returns...

Factors influencing return to work after hip and knee replacement.

PubMed

Malviya, A; Wilson, G; Kleim, B; Kurtz, S M; Deehan, D

2014-09-01

Return to employment is one of the key goals of joint replacement surgery in the working-age population. There is limited quantitative and qualitative research focusing on return to work after hip and knee replacement. It remains unclear why certain groups of patients are not able to achieve sufficient functional improvement to allow productive return to work while others can. Very little is known about the individual patient and employer perspectives in this regard. To review current evidence for the factors influencing employment outcomes in patients undergoing hip and knee replacement. Original articles and reviews in Medline, Embase and PsycINFO from 1987 to 2013 were included in the analysis. Age, patient motivation, employment before surgery and type of job were found to be important factors in determining return to work following hip and knee replacement. There is a need for further qualitative work on how and why these factors influence employment outcomes. © The Author 2014. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

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.

Community-Based Colorectal Cancer Screening in a Rural Population: Who Returns Fecal Immunochemical Test (FIT) Kits?

PubMed

Crosby, Richard A; Stradtman, Lindsay; Collins, Tom; Vanderpool, Robin

2017-09-01

To determine the return rate of community-delivered fecal immunochemical test (FIT) kits in a rural population and to identify significant predictors of returning kits. Residents were recruited in 8 rural Kentucky counties to enroll in the study and receive an FIT kit. Of 345 recruited, 82.0% returned an FIT kit from the point of distribution. These participants were compared to the remainder relative to age, sex, marital status, having an annual income below $15,000, not graduating from high school, not having a regular health care provider, not having health care coverage, being a current smoker, indicating current overweight or obese status, and a scale measure of fatalism pertaining to colorectal cancer. Predictors achieving significance at the bivariate level were entered into a stepwise logistic regression model to calculate adjusted OR and 95% CI. The return rate was 82.0%. In adjusted analyses, those indicating an annual income of less than $15,000 were 2.85 times more likely to return their kits (95% CI: 1.56-5.24; P < .001). Also, those not perceiving themselves to be overweight/obese were 1.95 times more likely to return their kits (95% CI: 1.07-3.55; P = .029). An outreach-based colorectal cancer screening program in a rural population may yield high return rates. People with annual incomes below $15,000 and those not having perceptions of being overweight/obese may be particularly likely to return FIT kits. © 2016 National Rural Health Association.

Deep inflow into the Mozambique Basin

NASA Astrophysics Data System (ADS)

Read, J. F.; Pollard, R. T.

1999-02-01

More than 200 conductivity-temperature-depth (CTD) stations were worked around the Southwest Indian Ridge and Del Caño Rise as part of the World Ocean Circulation Experiment. A selection of these data provides information about the inflow of bottom water into the Mozambique Basin. The basin is closed below 3000 m, yet the inflow is significantly large, of order 1 Sv (1 Sv = 106 m3 s-1). Estimates of the basin-scale upwelling at 4000 m suggest that the vertical velocity is also large, 10 × 10-5 cm s-1 or more, an order of magnitude greater than global ocean estimates. Examination of the characteristics of the bottom water in the Mozambique and Agulhas Basins and the Prince Edward Fracture Zone shows that bottom water enters the Mozambique Basin from the Agulhas Basin and also directly from the Enderby Basin. Most of the transport enters the Mozambique Basin via the Agulhas Basin, where two regions of northward flow below 4000 m are found. The major flow, on the eastern flank of the Mozambique Ridge, is through and above the deep, extending (5900 m) trench that connects the Agulhas and Mozambique Basins. The second, weaker flow enters the Transkei Basin along the deep eastern flank of the Agulhas Plateau, then turning east into the Mozambique Basin. The only source of bottom water to the Agulhas Basin is the Enderby Basin, but a more direct route between the Enderby and Mozambique Basins exists via the Prince Edward fracture, which extends deeper than 4000 m throughout its length and links the two basins directly across the Southwest Indian Ridge. Full depth CTD stations trace the changing characteristics of the deep and bottom water in the fracture, and moored current meter data show the strength and persistence of the throughflow. Strong mixing with the overlying deep water elevates the salt content of the bottom water by comparison with the other water in the Mozambique Basin. Thus two distinct bottom waters of the Mozambique Basin originate in the same place

The propagation speed of a positive lightning return stroke

NASA Technical Reports Server (NTRS)

Idone, Vincent P.; Orville, Richard E.; Mach, Douglas M.; Rust, W. David

1987-01-01

The first direct determination of the propagation speed of a lightning return stroke lowering positive charge to ground has been made. This stroke was the third of eight otherwise negative strokes in a triggered lightning flash initiated at the Kennedy Space Center, FL. Two independent optical systems, one photographic and the other photoelectric, yielded common recordings for the third and fourth strokes; the respective two-dimensional return stroke propagation speeds were 1.0 vs 0.93 x 10 to the 8th m/s for the positive (third) stroke and 1.0 vs 1.0 x 10 to the 8th m/s for the fourth stroke. Using fast electric-field data, the positive stroke peak current was estimated to be 21 kA. Photoelectric data only yielded propagation speeds of 1.4, 1.6, 1.2, 1.3, 1.0 and 0.90 x 10 to the 8th m/s for the first, second and fifth through eighth return strokes, respectively.

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

On-Ice Return-to-Hockey Progression After Anterior Cruciate Ligament Reconstruction.

PubMed

Capin, Jacob J; Behrns, William; Thatcher, Karen; Arundale, Amelia; Smith, Angela Hutchinson; Snyder-Mackler, Lynn

2017-05-01

Synopsis The literature pertaining to the rehabilitation of ice hockey players seeking to return to sport after anterior cruciate ligament reconstruction (ACLR) is currently limited. The purpose of this clinical commentary was to present a criterion-based progression for return to ice hockey for athletes after ACLR. First, we review pertinent literature and provide previously published guidelines on general rehabilitation after ACLR. Then, we present a 4-phase, on-ice skating progression with objective criteria to initiate each phase. During the early on-ice phase, the athlete is reintroduced to specific demands, including graded exposure to forward, backward, and crossover skating. In the intermediate on-ice phase, the emphasis shifts to developing power and introducing anticipated changes of direction within a controlled environment. During the late on-ice phase, the focus progresses to developing anaerobic endurance and introducing unanticipated changes of direction, but still without other players or contact. Finally, once objective return-to-sport criteria are met, noncontact team drills, outnumbered and even-numbered drills, practices, scrimmages, and games are progressively reintroduced during the return-to-sport phase. Recommendations for off-ice strength and conditioning exercises complement the on-ice progression. Additionally, we apply the return-to-hockey progression framework to a case report of a female collegiate defensive ice hockey player who returned to sport successfully after ACLR. This criterion-based return-to-hockey progression may guide rehabilitation specialists managing athletes returning to ice hockey after ACLR. J Orthop Sports Phys Ther 2017;47(5):324-333. Epub 29 Mar 2017. doi:10.2519/jospt.2017.7245.

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.

Mars Sample Return - Launch and Detection Strategies for Orbital Rendezvous

NASA Technical Reports Server (NTRS)

Woolley, Ryan C.; Mattingly, Richard L.; Riedel, Joseph E.; Sturm, Erick J.

2011-01-01

This study sets forth conceptual mission design strategies for the ascent and rendezvous phase of the proposed NASA/ESA joint Mars Sample Return Campaign. The current notional mission architecture calls for the launch of an acquisition/cache rover in 2018, an orbiter with an Earth return vehicle in 2022, and a fetch rover and ascent vehicle in 2024. Strategies are presented to launch the sample into a coplanar orbit with the Orbiter which facilitate robust optical detection, orbit determination, and rendezvous. Repeating ground track orbits exist at 457 and 572 km which provide multiple launch opportunities with similar geometries for detection and rendezvous.

Mars Sample Return: Launch and Detection Strategies for Orbital Rendezvous

NASA Technical Reports Server (NTRS)

Woolley, Ryan C.; Mattingly, Richard L.; Riedel, Joseph E.; Sturm, Erick J.

2011-01-01

This study sets forth conceptual mission design strategies for the ascent and rendezvous phase of the proposed NASA/ESA joint Mars Sample Return Campaign. The current notional mission architecture calls for the launch of an acquisition/ caching rover in 2018, an Earth return orbiter in 2022, and a fetch rover with ascent vehicle in 2024. Strategies are presented to launch the sample into a nearly coplanar orbit with the Orbiter which would facilitate robust optical detection, orbit determination, and rendezvous. Repeating ground track orbits existat 457 and 572 km which would provide multiple launch opportunities with similar geometries for detection and rendezvous.

Project Hyreus: Mars Sample Return Mission Utilizing in Situ Propellant Production

NASA Technical Reports Server (NTRS)

Bruckner, A. P.; Thill, Brian; Abrego, Anita; Koch, Amber; Kruse, Ross; Nicholson, Heather; Nill, Laurie; Schubert, Heidi; Schug, Eric; Smith, Brian

1993-01-01

Project Hyreus is an unmanned Mars sample return mission that utilizes propellants manufactured in situ from the Martian atmosphere for the return voyage. A key goal of the mission is to demonstrate the considerable benefits of using indigenous resources and to test the viability of this approach as a precursor to manned Mars missions. The techniques, materials, and equipment used in Project Hyreus represent those that are currently available or that could be developed and readied in time for the proposed launch date in 2003. Project Hyreus includes such features as a Mars-orbiting satellite equipped with ground-penetrating radar, a large rover capable of sample gathering and detailed surface investigations, and a planetary science array to perform on-site research before samples are returned to Earth. Project Hyreus calls for the Mars Landing Vehicle to land in the Mangala Valles region of Mars, where it will remain for approximately 1.5 years. Methane and oxygen propellant for the Earth return voyage will be produced using carbon dioxide from the Martian atmosphere and a small supply of hydrogen brought from Earth. This process is key to returning a large Martian sample to Earth with a single Earth launch.

Project Hyreus: Mars sample return mission utilizing in situ propellant production

NASA Technical Reports Server (NTRS)

Abrego, Anita; Bair, Chris; Hink, Anthony; Kim, Jae; Koch, Amber; Kruse, Ross; Ngo, Dung; Nicholson, Heather; Nill, Laurie; Perras, Craig

1993-01-01

Project Hyreus is an unmanned Mars sample return mission that utilizes propellants manufactured in situ from the Martian atmosphere for the return voyage. A key goal of the mission is to demonstrate the considerable benefits of using indigenous resources and to test the viability of this approach as a precursor to manned Mars missions. The techniques, materials, and equipment used in Project Hyreus represent those that are currently available or that could be developed and readied in time for the proposed launch date in 2003. Project Hyreus includes such features as a Mars-orbiting satellite equipped with ground-penetrating radar, a large rover capable of sample gathering and detailed surface investigations, and a planetary science array to perform on-site research before samples are returned to Earth. Project Hyreus calls for the Mars Landing Vehicle to land in the Mangala Valles region of Mars, where it will remain for approximately 1.5 years. Methane and oxygen propellant for the Earth return voyage will be produced using carbon dioxide from the Martian atmosphere and a small supply of hydrogen brought from Earth. This process is key to returning a large Martian sample to Earth with a single Earth launch.

76 FR 17521 - Specified Tax Return Preparers Required To File Individual Income Tax Returns Using Magnetic Media

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-30

... Specified Tax Return Preparers Required To File Individual Income Tax Returns Using Magnetic Media AGENCY... regulations on the requirement for ``specified tax return preparers'' to file individual income tax returns.... These regulations provide guidance to specified tax return preparers who prepare and file individual...

Implications of net energy-return-on-investment for a low-carbon energy transition

NASA Astrophysics Data System (ADS)

King, Lewis C.; van den Bergh, Jeroen C. J. M.

2018-04-01

Low-carbon energy transitions aim to stay within a carbon budget that limits potential climate change to 2 °C—or well below—through a substantial growth in renewable energy sources alongside improved energy efficiency and carbon capture and storage. Current scenarios tend to overlook their low net energy returns compared to the existing fossil fuel infrastructure. Correcting from gross to net energy, we show that a low-carbon transition would probably lead to a 24-31% decline in net energy per capita by 2050, which implies a strong reversal of the recent rising trends of 0.5% per annum. Unless vast end-use efficiency savings can be achieved in the coming decades, current lifestyles might be impaired. To maintain the present net energy returns, solar and wind renewable power sources should grow two to three times faster than in other proposals. We suggest a new indicator, `energy return on carbon', to assist in maximizing the net energy from the remaining carbon budget.

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

Returning individual research results for genome sequences of pancreatic cancer

PubMed Central

2014-01-01

Background Disclosure of individual results to participants in genomic research is a complex and contentious issue. There are many existing commentaries and opinion pieces on the topic, but little empirical data concerning actual cases describing how individual results have been returned. Thus, the real life risks and benefits of disclosing individual research results to participants are rarely if ever presented as part of this debate. Methods The Australian Pancreatic Cancer Genome Initiative (APGI) is an Australian contribution to the International Cancer Genome Consortium (ICGC), that involves prospective sequencing of tumor and normal genomes of study participants with pancreatic cancer in Australia. We present three examples that illustrate different facets of how research results may arise, and how they may be returned to individuals within an ethically defensible and clinically practical framework. This framework includes the necessary elements identified by others including consent, determination of the significance of results and which to return, delineation of the responsibility for communication and the clinical pathway for managing the consequences of returning results. Results Of 285 recruited patients, we returned results to a total of 25 with no adverse events to date. These included four that were classified as medically actionable, nine as clinically significant and eight that were returned at the request of the treating clinician. Case studies presented depict instances where research results impacted on cancer susceptibility, current treatment and diagnosis, and illustrate key practical challenges of developing an effective framework. Conclusions We suggest that return of individual results is both feasible and ethically defensible but only within the context of a robust framework that involves a close relationship between researchers and clinicians. PMID:24963353

Stormwater Design Return Period Standards for U.S. Transportation Infrastructure: How Are States Approaching Resilience?

NASA Astrophysics Data System (ADS)

Samaras, C.; Lopez, T.

2016-12-01

Climate change is projected to increase the frequency and intensity of precipitation in many regions, which is relevant for stormwater engineering designs and resilience in the transportation sector. Existing and future stormwater infrastructure is generally designed for historical and stationary hydrologic conditions. For example, the design return period is based on statistical analysis of past precipitation events, often over a 50-year historical timeline. The design return period translates into how much peak precipitation volume a system is designed for in a state, and provides information about the performance of a drainage structure. The higher the design period used by an engineer for a given stormwater system, the more peak stormwater volume the system can convey. Therefore, design return periods can be associated with a design's near-term and long-term resilience. However, there is a tradeoff between the choice of design return period, the total infrastructure capital cost, and the resilience of a system to heavy precipitation events. This study analyzes current stormwater infrastructure design guidelines for state departments of transportation in the contiguous United States, in order to understand how stormwater design return periods vary across states and provide insight into the resilience of current stormwater systems design. The study found that the design return period varies considerably across the United States by roadway functional class and drainage classification, as well as within climate regions. Understanding this variation will help states identify possible vulnerabilities, highlight deficiencies across states and infrastructure types, and help in updating design return periods to increase the climate resilience of stormwater infrastructure.

Mars Sample Return Architecture Overview

NASA Astrophysics Data System (ADS)

Edwards, C. D.; Vijendran, S.

2018-04-01

NASA and ESA are exploring potential concepts for a Sample Retrieval Lander and Earth Return Orbiter that could return samples planned to be collected and cached by the Mars 2020 rover mission. We provide an overview of the Mars Sample Return architecture.

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. [T.D. 9445, 74 FR 6830, Feb. 11, 2009] ...

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. [T.D. 9445, 74 FR 6830, Feb. 11, 2009] ...

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. [T.D. 9445, 74 FR 6830, Feb. 11, 2009] ...

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. [T.D. 9445, 74 FR 6830, Feb. 11, 2009] ...

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. [T.D. 9445, 74 FR 6830, Feb. 11, 2009] ...

The effect that energy storage and return feet have on the propulsion of the body: a pilot study.

PubMed

Crimin, Anthony; McGarry, Anthony; Harris, Elena Jane; Solomonidis, Stephan Emanuel

2014-09-01

A variety of energy storage and return prosthetic feet are currently available for use within lower limb prostheses. Designs claim to provide a beneficial energy return during push-off, but the extent to which this occurs remains disputed. Techniques currently used to measure energy storage, dissipation and return within the structure of the prosthetic foot are debatable, with limited evidence to support substantial elastic energy storage and return from existing designs. The aim of this study was to evaluate the performance of energy storage and return foot designs through considering the ankle power during push-off and the effect on body centre of mass propulsion. To achieve this aim, the gait patterns of six trans-tibial prosthetic users wearing different designs of energy storage and return feet were analysed while ascending a ramp. Three examples of energy storage and return feet (suitable for moderate activity) were selected and randomly evaluated: the Blatchford's Epirus, Össur Assure and College Park Tribute feet. The power at the anatomical and mechanical ankle joints was integrated to evaluate the work done over the gait cycle. The direction of the inertial force, and therefore propulsion of the body centre of mass, was used to indicate the effect of the energy return by the energy storage and return feet. Results indicate that although energy storage and return feet may provide energy return, the work done around the prosthetic ankle indicates net power absorption. Therefore, the prosthetic limb is unable to contribute to the body centre of mass propulsion to the same extent as the biological limb. © IMechE 2014.

26 CFR 20.6018-2 - Returns; person required to file return.

Code of Federal Regulations, 2010 CFR

2010-04-01

... executor or administrator shall file the return. If there is more than one executor or administrator, the return must be made jointly by all. If there is no executor or administrator appointed, qualified and... decedent situated in the United States is constituted an executor for purposes of the tax (see § 20.2203-1...

12 CFR 229.31 - Returning bank's responsibility for return of checks.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Returning bank's responsibility for return of checks. 229.31 Section 229.31 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF... following the banking day on which the check was presented to the paying bank if the paying bank is located...

Return to Sport in the Younger Patient With Anterior Cruciate Ligament Reconstruction

PubMed Central

Webster, Kate E.; Feller, Julian A.; Whitehead, Timothy S.; Myer, Gregory D.; Merory, Peter B.

2017-01-01

Background: Although anterior cruciate ligament (ACL) reconstruction is generally regarded as a successful procedure, only 65% of patients return to their preinjury sport. While return-to-sport rates are likely higher in younger patients, there is a paucity of data that focus on the younger patient and their return-to-sport experience after ACL reconstruction. Purpose: To investigate a range of return-to-sport outcomes in younger athletes who had undergone ACL reconstruction surgery. Study Design: Case series; Level of evidence, 4. Methods: A group of 140 young patients (<20 years old at surgery) who had 1 ACL reconstruction and no subsequent ACL injuries completed a survey regarding details of their sport participation at a mean follow-up of 5 years (range, 3-7 years). Results: Overall, 76% (95% CI, 69%-83%) of the young patient group returned to the same preinjury sport. Return rates were higher for males than females (81% vs 71%, respectively; P > .05). Of those who returned to their sport, 65% reported that they could perform as well as before the ACL injury and 66% were still currently participating in their respective sport. Young athletes who never returned to sport cited fear of a new injury (37%) or study/work commitments (30%) as the primary reasons for dropout. For those who had successfully returned to their preinjury sport but subsequently stopped participating, the most common reason cited for stopping was study/work commitments (53%). At a mean 5-year follow-up, 48% of female patients were still participating in level I (jumping, hard pivoting) sports, as were 54% of males. Conclusion: A high percentage of younger patients return to their preinjury sport after ACL reconstruction surgery. For patients in this cohort who had not sustained a second ACL injury, the majority continue to participate and are satisfied with their performance. PMID:28473996

Astrobiology Objectives for Mars Sample Return

NASA Astrophysics Data System (ADS)

Meyer, M. A.

2002-05-01

Astrobiology is the study of life in the Universe, and a major objective is to understand the past, present, and future biologic potential of Mars. The current Mars Exploration Program encompasses a series of missions for reconnaissance and in-situ analyses to define in time and space the degree of habitability on Mars. Determining whether life ever existed on Mars is a more demanding question as evidenced by controversies concerning the biogenicity of features in the Mars meteorite ALH84001 and in the earliest rocks on Earth. In-situ studies may find samples of extreme interest but resolution of the life question most probably would require a sample returned to Earth. A selected sample from Mars has the many advantages: State-of-the-art instruments, precision sample handling and processing, scrutiny by different investigators employing different techniques, and adaptation of approach to any surprises It is with a returned sample from Mars that Astrobiology has the most to gain in determining whether life did, does, or could exist on Mars.

Return to Flying Duties Following Centrifuge or Vibration Exposures

NASA Technical Reports Server (NTRS)

Scheuring, Richard A.; Clarke, Jonathan; Jones, Jeffrey A.

2009-01-01

Introduction: In an effort to determine the human performance limits for vibration in spacecraft being developed by NASA, astronauts were evaluated during a simulated launch profile in a centrifuge/vibration environment and separate vibration-only simulation. Current USAF and Army standards for return to flight following centrifuge exposures require 12-24 hours to pass before a crewmember may return to flying duties. There are no standards on vibration exposures and return to flying duties. Based on direct observation and provocative neurological testing of the astronauts, a new standard for return to flying duties following centrifuge and/or vibration exposures was established. Methods: 13 astronaut participants were exposed to simulated launch profiles in a + 3.5 Gx bias centrifuge/vibration environment and separately on a vibration table at the NASA-Ames Research Center. Each subject had complete neurological evaluations pre- and post-exposure for the centrifuge/vibration runs with the NASA neurological function rating scale (NFRS). Subjects who participated in the vibration-only exposures had video oculography performed with provocative maneuvers in addition to the NFRS. NFRS evaluations occurred immediately following each exposure and at 1 hour post-run. Astronauts who remained symptomatic at 1 hour had repeat NFRS performed at 1 hour intervals until the crewmember was asymptomatic. Results: Astronauts in the centrifuge/vibration study averaged a 3-5 point increase in NFRS scores immediately following exposure but returned to baseline 3 hours post-run. Subjects exposed to the vibration-only simulation had a 1-3 point increase following exposure and returned to baseline within 1-2 hours. Pre- and post- vibration exposure video oculography did not reveal any persistent ocular findings with provocative testing 1 hour post-exposure. Discussion: Based on direct observations and objective measurement of neurological function in astronauts following simulated launch

Observations of the southern East Madagascar Current and undercurrent and countercurrent system

NASA Astrophysics Data System (ADS)

Nauw, J. J.; van Aken, H. M.; Webb, A.; Lutjeharms, J. R. E.; de Ruijter, W. P. M.

2008-08-01

In April 2001 four hydrographic sections perpendicular to the southern East Madagascar Current were surveyed as part of the Agulhas Current Sources Experiment. Observations with a vessel mounted and a lowered ADCP produced information on the current field while temperature, salinity, oxygen and nutrient data obtained with a CTD-Rosette system, gave information on the water mass structure of the currents southeast of Madagascar. The peak velocity in the pole-ward East Madagascar Current through these four sections had a typical magnitude of ˜110 cm/s, while the width of this current was of the order of 120 km. The mean pole-ward volume transport rate of this current during the survey above the 5°C isotherm was estimated to be 37 ± 10 Sv. On all four sections an undercurrent was observed at intermediate depths below the East Madagascar Current. Its equator-ward transport rate amounted to 2.8 ± 1.4 Sv. Offshore of the East Madagascar Current the shallow South Indian Ocean Countercurrent was observed. This eastward frontal jet coincided with the barotropic and thermohaline front that separates the saline Subtropical Surface Water from the fresher Tropical Surface Water in the East Madagascar Current. The near-surface geostrophic flow of the East Madagascar Current, derived from satellite altimetry data from 1992 to 2005, suggests a strong variability of this transport due to eddy variability and interannual changes. The long-term pole-ward mean transport of the East Madagascar Current, roughly estimated from those altimetry data amounts to 32 Sv. The upper-ocean water mass of the East Madagascar Current was very saline in 2001, compared to WOCE surveys from 1995. Comparison of our undercurrent data with those of the WOCE surveys in 1995 confirms that the undercurrent is a recurrent feature. Its water mass properties are relatively saline, due to the presence of water originating from the Red Sea outflow at intermediate levels. The saline water was advected from the

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…

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.

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 by...

Variables Associated With Return to Sport Following Anterior Cruciate Ligament Reconstruction: A Systematic Review

PubMed Central

Czuppon, Sylvia; Racette, Brad A.; Klein, Sandra E.; Harris-Hayes, Marcie

2014-01-01

Background As one of the purposes of anterior cruciate ligament reconstruction (ACLR) is to return athletes to their pre-injury activity level, it is critical to understand variables influencing return to sport. Associations between return to sport and variables representing knee impairment, function and psychological status have not been well studied in athletes following ACLR. Purpose The purpose of this review is to summarize the literature reporting on variables proposed to be associated with return to sport following anterior cruciate ligament reconstruction. Study Design Systematic Review Methods Medline, Embase, CINAHL and Cochrane databases were searched for articles published before November 2012. Articles included in this review met these criteria: 1) included patients with primary ACLR, 2) reported at least one knee impairment, function or psychological measure, 3) reported a return to sport measure and 4) analyzed the relationship between the measure and return to sport. Results Weak evidence existed in sixteen articles suggesting variables associated with return to sport included higher quadriceps strength, less effusion, less pain, greater tibial rotation, higher Marx Activity score, higher athletic confidence, higher pre-operative knee self-efficacy, lower kinesiophobia and higher pre-operative self-motivation. Conclusion Weak evidence supports an association between knee impairment, functional, and psychological variables and return to sport. Current return to sport guidelines should be updated to reflect all variables associated with return to sport. Utilizing evidence-based return to sport guidelines following ACLR may ensure athletes are physically and psychologically capable of sports participation, which may reduce re-injury rates and the need for subsequent surgery. PMID:24124040

In-line beam current monitor

DOEpatents

Ekdahl, Jr., Carl A.; Frost, Charles A.

1986-01-01

An intense relativistic electron beam current monitor for a gas neutralized beam transport line includes a first foil for conducting plasma current to the wall where it is measured as it traverses an inductive loop formed by a cavity in the wall. An insulator foil separates the first foil from a second conducting foil which returns the current to the plasma environment.

In-line beam current monitor

DOEpatents

Ekdahl, C.A. Jr.; Frost, C.A.

1984-11-13

An intense relativistic electron beam current monitor for a gas neutralized beam transport line includes a first foil for conducting plasma current to the wall where it is measured as it traverses an inductive loop formed by a cavity in the wall. An insulator foil separates the first foil from a second conducting foil which returns the current to the plasma environment.

Calculations of lightning return stroke electric and magnetic fields above ground

NASA Technical Reports Server (NTRS)

Master, M. J.; Uman, M. A.; Ling, Y. T.; Standler, R. B.

1981-01-01

Lin et al., (1980) presented a lightning return stroke model with which return stroke electric and magnetic fields measured at ground level could be reproduced. This model and a modified version of it, in which the initial current peak decays with height above ground, are used to compute waveforms for altitudes from 0-10 km and at ranges of 20 m to 10 km. Both the original and modified models gave accurate predictions of measured ground-based fields. The use of the calculated fields in calibrating airborne field measurements from simultaneous ground and airborne data is discussed.

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.…

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

US Navy Operational Global Ocean and Arctic Ice Prediction Systems

DTIC Science & Technology

2014-09-01

meridional overturning circulation (Figure 29 in Hurlburt et al., 2011), when comparing a non-assimilative simulation with a data assimilative...boundary current regions of the Gulf Stream ( Atlantic ), the Kuroshio (Pacific), and the Agulhas and Somali Currents (both Indian). Consequently...Oceanic and Atmospheric Administration at the National Centers for Environmental Prediction (NCEP), initially for the North Atlantic (Mehra and

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…

"Brain Drain" from Turkey: Survey Evidence of Student Non-Return.

ERIC Educational Resources Information Center

Tansel, Aysit; Gungor, Nil Demet

2003-01-01

An Internet survey of Turkish students studying abroad received 1,103 responses. Although 53% initially intended to return, only 13.5% have that intention currently. Reasons for staying abroad include better career prospects, Turkish economic conditions, lack of relevant work in Turkey, and avoidance of compulsory military service. (Contains 28…

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.'

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 and...

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 and...

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 and...

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 and...

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 and...

21st century early mission concepts for Mars delivery and earth return

NASA Technical Reports Server (NTRS)

Cruz, Manuel I.; Ilgen, Marc R.

1990-01-01

In the 21st century, the early missions to Mars will entail unmanned Rover and Sample Return reconnaissance missions to be followed by manned exploration missions. High performance leverage technologies will be required to reach Mars and return to earth. This paper describes the mission concepts currently identified for these early Mars missions. These concepts include requirements and capabilities for Mars and earth aerocapture, Mars surface operations and ascent, and Mars and earth rendezvous. Although the focus is on the unmanned missions, synergism with the manned missions is also discussed.

Socioeconomic Status and Self-Rated Oral Health; Diminished Return among Hispanic Whites.

PubMed

Assari, Shervin

2018-04-24

Background. An extensive body of knowledge has documented weaker health effects of socio-economic status (SES) for Blacks compared to Whites, a phenomenon also known as Blacks’ diminished return. It is, however, unknown whether the same diminished return also holds for other ethnic minorities such as Hispanics or not. Aim. Using a nationally representative sample, the current study aimed to compare Non-Hispanic and Hispanic Whites for the effects of SES on self-rated oral health. Methods. For the current cross-sectional study, we used data from the Collaborative Psychiatric Epidemiology Surveys (CPES), 2001⁻2003. With a nationally representative sampling, CPES included 11,207 adults who were either non-Hispanic Whites ( n = 7587) or Hispanic Whites ( n = 3620. The dependent variable was self-rated oral health, treated as dichotomous measure. Independent variables were education, income, employment, and marital status. Ethnicity was the focal moderator. Age and gender were covariates. Logistic regressions were used for data analysis. Results. Education, income, employment, and marital status were associated with oral health in the pooled sample. Although education, income, employment, and marital status were associated with oral health in non-Hispanic Whites, none of these associations were found for Hispanic Whites. Conclusion. In a similar pattern to Blacks’ diminished return, differential gain of SES indicators exists between Hispanic and non-Hispanic Whites, with a disadvantage for Hispanic Whites. Diminished return of SES should be regarded as a systemically neglected contributing mechanism behind ethnic oral health disparities in the United States. Replication of Blacks’ diminished return for Hispanics suggests that these processes are not specific to ethnic minority groups, and non-White groups gain less because they are not enjoying the privilege and advantage of Whites.

49 CFR 1152.34 - Return on investment.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 8 2010-10-01 2010-10-01 false Return on investment. 1152.34 Section 1152.34... Return on investment. Return on investment for road property shall be computed according to the procedures set forth in this section. (a)-(b) [Reserved] (c) Return on investment—road properties. Return on...

49 CFR 1152.34 - Return on investment.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 8 2011-10-01 2011-10-01 false Return on investment. 1152.34 Section 1152.34... Return on investment. Return on investment for road property shall be computed according to the procedures set forth in this section. (a)-(b) [Reserved] (c) Return on investment—road properties. Return on...

Mars Sample Return Landed with Red Dragon

NASA Technical Reports Server (NTRS)

Stoker, Carol R.; Lemke, Lawrence G.

2013-01-01

A Mars Sample Return (MSR) mission is the highest priority science mission for the next decade as recommended by the recent Decadal Survey of Planetary Science. However, an affordable program to carry this out has not been defined. This paper describes a study that examined use of emerging commercial capabilities to land the sample return elements, with the goal of reducing mission cost. A team at NASA Ames examined the feasibility of the following scenario for MSR: A Falcon Heavy launcher injects a SpaceX Dragon crew capsule and trunk onto a Trans Mars Injection trajectory. The capsule is modified to carry all the hardware needed to return samples collected on Mars including a Mars Ascent Vehicle (MAV), an Earth Return Vehicle (ERV) and Sample Collection and Storage hardware. The Dragon descends to land on the surface of Mars using SuperSonic Retro Propulsion (SSRP) as described by Braun and Manning [IEEEAC paper 0076, 2005]. Samples are acquired and deliverd to the MAV by a prelanded asset, possibly the proposed 2020 rover. After samples are obtained and stored in the ERV, the MAV launches the sample-containing ERV from the surface of Mars. We examined cases where the ERV is delivered to either low Mars orbit (LMO), C3 = 0 (Mars escape), or an intermediate energy state. The ERV then provides the rest of the energy (delta V) required to perform trans-Earth injection (TEI), cruise, and insertion into a Moon-trailing Earth Orbit (MTEO). A later mission, possibly a crewed Dragon launched by a Falcon Heavy (not part of the current study) retrieves the sample container, packages the sample, and performs a controlled Earth re-entry to prevent Mars materials from accidentally contaminating Earth. The key analysis methods used in the study employed a set of parametric mass estimating relationships (MERs) and standard aerospace analysis software codes modified for the MAV class of launch vehicle to determine the range of performance parameters that produced converged

Particle-in-cell simulations of electron beam control using an inductive current divider

DOE PAGES

Swanekamp, S. B.; Angus, J. R.; Cooperstein, G.; ...

2015-11-18

Kinetic, time-dependent, electromagnetic, particle-in-cell simulations of the inductive current divider are presented. The inductive current divider is a passive method for controlling the trajectory of an intense, hollow electron beam using a vacuum structure that inductively splits the beam’s return current. The current divider concept was proposed and studied theoretically in a previous publication [Phys. Plasmas 22, 023107 (2015)] A central post carries a portion of the return current (I 1) while the outer conductor carries the remainder (I 2) with the injected beam current given by I b=I 1+I 2. The simulations are in agreement with the theory whichmore » predicts that the total force on the beam trajectory is proportional to (I 2-I 1) and the force on the beam envelope is proportional to I b. For a fixed central post, the beam trajectory is controlled by varying the outer conductor radius which changes the inductance in the return-current path. The simulations show that the beam emittance is approximately constant as the beam propagates through the current divider to the target. As a result, independent control over both the current density and the beam angle at the target is possible by choosing the appropriate return-current geometry.« less

Return to play after liver and spleen trauma.

PubMed

Juyia, Rushad F; Kerr, Hamish A

2014-05-01

Sport-related spleen and liver injuries pose a challenge for the physician. Although rare, these injuries can have serious and even life-threatening outcomes if not accurately diagnosed and managed in a timely fashion. Currently, there are no evidence-based guidelines on duration and intensity of restricted activity and return to play after spleen and liver injury. In addition, there is controversy on follow-up imaging after injury. PubMed was searched using the terms splenic or spleen and trauma and hepatic or liver and trauma from 1980 to 2013. The citations from sentinel papers were also reviewed. Clinical review. Level 3. Ultrasound is ideal in the unstable athlete. Nonoperative management of blunt splenic and hepatic injuries is recommended for hemodynamically stable patients regardless of injury grade, patient age, or presence of associated injuries. Follow-up imaging is not routinely recommended unless clinically indicated. Athletes may engage in light activity for the first 3 months after injury and then gradual return to unrestricted activity as tolerated. High-level athletes may choose splenectomy or serial imaging for faster return to play. Intravenous contrast-enhanced computed tomography is the diagnostic imaging modality of choice in stable athletes with blunt abdominal trauma. C.

Dynamical Analysis of the Boundary Layer and Surface Wind Responses to Mesoscale SST Perturbations

DTIC Science & Technology

2010-02-01

latitude (e.g., Gille and Romero 2003; Lumpkin and Pazos 2007). We thus expect that inclusion of ocean current effects in the surface stress computations...Niiler, 2007: Ocean–atmosphere interaction over Agulhas Extension meanders. J. Climate, 20, 5784–5797. Lumpkin, R., and M. Pazos , 2007: Measuring surface

Aerothermodynamic environments for Mars entry, Mars return, and lunar return aerobraking missions

NASA Astrophysics Data System (ADS)

Rochelle, W. C.; Bouslog, S. A.; Ting, P. C.; Curry, D. M.

1990-06-01

The aeroheating environments to vehicles undergoing Mars aerocapture, earth aerocapture from Mars, and earth aerocapture from the moon are presented. An engineering approach for the analysis of various types of vehicles and trajectories was taken, rather than performing a benchmark computation for a specific point at a selected time point in a trajectory. The radiation into Mars using the Mars Rover Sample Return (MRSR) 2-ft nose radius bionic remains a small contributor of heating for 6 to 10 km/sec; however, at 12 km/sec it becomes comparable with the convection. For earth aerocapture, returning from Mars, peak radiation for the MRSR SRC is only 25 percent of the peak convection for the 12-km/sec trajectory. However, when large vehicles are considered with this trajectory, peak radiation can become 2 to 4 times higher than the peak convection. For both Mars entry and return, a partially ablative Thermal Protection System (TPS) would be required, but for Lunar Transfer Vehicle return an all-reusable TPS can be used.

Return Migration as Failure or Success?: The Determinants of Return Migration Intentions Among Moroccan Migrants in Europe.

PubMed

de Haas, Hein; Fokkema, Tineke; Fihri, Mohamed Fassi

Different migration theories generate competing hypotheses with regard to determinants of return migration. While neoclassical migration theory associates migration to the failure to integrate at the destination, the new economics of labour migration sees return migration as the logical stage after migrants have earned sufficient assets and knowledge and to invest in their origin countries. The projected return is then likely to be postponed for sustained or indefinite periods if integration is unsuccessful. So, from an indication or result of integration failure return is rather seen as a measure of success. Drawing on recent survey data ( N  = 2,832), this article tests these hypotheses by examining the main determinants of return intention among Moroccan migrants across Europe. The results indicate that structural integration through labour market participation, education and the maintenance of economic and social ties with receiving countries do not significantly affect return intentions. At the same time, investments and social ties to Morocco are positively related, and socio-cultural integration in receiving countries is negatively related to return migration intentions. The mixed results corroborate the idea that there is no uniform process of (return) migration and that competing theories might therefore be partly complementary.

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

Code of Federal Regulations, 2011 CFR

2011-04-01

... 26 Internal Revenue 18 2011-04-01 2011-04-01 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 return...

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 return...

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

Code of Federal Regulations, 2013 CFR

2013-04-01

... 26 Internal Revenue 18 2013-04-01 2013-04-01 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 return...

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

Code of Federal Regulations, 2012 CFR

2012-04-01

... 26 Internal Revenue 18 2012-04-01 2012-04-01 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 return...

Educating Providers in Return-to-Play Suggested Guidelines Postconcussion.

PubMed

Bires, Angela Macci; Leonard, Amanda L; Thurber, Brandon

As the awareness of concussions increases, it is imperative to be able to evaluate, diagnose, and treat concussed individuals properly to prevent further complications or death. The primary purpose of this study was to compare a provider's current awareness and comfort level as it relates to the return-to-play guidelines for concussions. A secondary aim was to evaluate current protocols that are in use and determine whether they coincide with the suggested guidelines. An educational intervention was implemented to assess the knowledge and confidence of health care providers. The study design was a quantitative, convenient sample, pretest/posttest questionnaire. The questionnaire was administered to participants who were nurse practitioners prior to an educational PowerPoint presentation. At 8 weeks, the posttest was administered. Approximately 19% of individuals were not aware of a graded return-to-play protocols. The findings suggest that the educational intervention increased their confidence levels in making a diagnosis of a concussion, in assessing danger signs, and in understanding when to refer to a specialist. Additional supporting evidence from this study indicates that the educational intervention allowed the participants to achieve a greater comfort level in finding appropriate resources for them and their patients.

26 CFR 1.6033-4 - 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 13 2010-04-01 2010-04-01 false Required use of magnetic media for returns by... 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 media under...

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 media...

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

Code of Federal Regulations, 2011 CFR

2011-04-01

... 26 Internal Revenue 13 2011-04-01 2011-04-01 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 media...

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

Code of Federal Regulations, 2012 CFR

2012-04-01

... 26 Internal Revenue 13 2012-04-01 2012-04-01 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 media...

76 FR 22611 - Specified Tax Return Preparers Required To File Individual Income Tax Returns Using Magnetic...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-22

... DEPARTMENT OF THE TREASURY Internal Revenue Service 26 CFR Part 301 [TD 9518] RIN 1545-BJ52 Specified Tax Return Preparers Required To File Individual Income Tax Returns Using Magnetic Media... who prepare and file individual income tax returns using magnetic media pursuant to section 6011(e)(3...

Return to sport after total or unicompartmental knee arthroplasty

PubMed Central

Dagneaux, Louis; Bourlez, Julien; Degeorge, Benjamin; Canovas, François

2017-01-01

Knee arthroplasty survival rate — either UKA or TKA — is currently 95%, greater than it was ten years ago, but has not been specifically evaluated in very active patients practicing sport at a high intensity. The terms and conditions of return to physical activities are decided by the surgeon, the rehabilitation or Sports Medicine doctor, who needs to make sure that postoperative rehabilitation has been conducted optimally. Specifically, range of movement must be complete, muscular strengthening has to be sufficient and balance must be recovered by proprioception. Only after this stage (i.e. three to six months after surgery) can physical activities be resumed. Return to sport must be gentle and progressive, with moderate activities limited to short sessions. Progressively the patient will be able to return to intermediate activities, provided that he/she possesses the adequate level of technique for the sport. This up-to-date review for young surgeons and residents aims to provide an informative guide for patients regarding sport following knee arthroplasty. Cite this article: EFORT Open Rev 2017;2:496–501. DOI: 10.1302/2058-5241.2.170037 PMID:29387472

A Perishable Inventory Model with Return

NASA Astrophysics Data System (ADS)

Setiawan, S. W.; Lesmono, D.; Limansyah, T.

2018-04-01

In this paper, we develop a mathematical model for a perishable inventory with return by assuming deterministic demand and inventory dependent demand. By inventory dependent demand, it means that demand at certain time depends on the available inventory at that time with certain rate. In dealing with perishable items, we should consider deteriorating rate factor that corresponds to the decreasing quality of goods. There are also costs involved in this model such as purchasing, ordering, holding, shortage (backordering) and returning costs. These costs compose the total costs in the model that we want to minimize. In the model we seek for the optimal return time and order quantity. We assume that after some period of time, called return time, perishable items can be returned to the supplier at some returning costs. The supplier will then replace them in the next delivery. Some numerical experiments are given to illustrate our model and sensitivity analysis is performed as well. We found that as the deteriorating rate increases, returning time becomes shorter, the optimal order quantity and total cost increases. When considering the inventory-dependent demand factor, we found that as this factor increases, assuming a certain deteriorating rate, returning time becomes shorter, optimal order quantity becomes larger and the total cost increases.

Magnetobraking: Use of tether electrodynamic drag for Earth return from Mars

NASA Technical Reports Server (NTRS)

Landis, Geoffrey A.

1994-01-01

It has often been proposed that a vehicle returning from Mars will use aerobraking in the Earth's atmosphere to dissipate hyperbolic excess velocity to capture into Earth orbit. Here a different system for dissipating excess velocity without expenditure of reaction mass, magnetobraking, is proposed. Magnetobraking uses the force on an electrodynamic tether in the Earth's magnetic field to produce thrust. An electrodynamic tether is deployed from the spacecraft as it approaches the Earth. The Earth's magnetic field produces a force on electrical current in the tether. If the tether is oriented perpendicularly to the Earth's magnetic field and to the direction of motion of the spacecraft, force produced by the Earth's magnetic field can be used to either brake or accelerate the spacecraft without expenditure of reaction mass. The peak acceleration on the Mars return is 0.007 m/sq sec, and the amount of braking possible is dependent on the density and current-carrying capacity of the tether, but is independent of length. A superconducting tether is required. The required critical current is shown to be within the range of superconducting technology now available in the laboratory.

Return to Work After Diskogenic Fusion in Workers' Compensation Subjects.

PubMed

Anderson, Joshua T; Haas, Arnold R; Percy, Rick; Woods, Stephen T; Ahn, Uri M; Ahn, Nicholas U

2015-12-01

Lumbar fusion for degenerative disk disease (DDD) is associated with variable clinical outcomes. Patients with workers' compensation claims often have worse fusion outcomes than the general population. Few studies have evaluated the risk factors for poor outcomes within this clinically distinct population. The goal of this study was to identify preoperative predictors of return to work status after fusion for DDD in a workers' compensation setting. The authors used International Classification of Diseases, Ninth Revision (ICD-9), diagnosis and Current Procedural Terminology (CPT) procedural codes to identify 1037 subjects from the Ohio Bureau of Workers' Compensation database who underwent fusion for DDD between 1993 and 2013. Of these subjects, 23.2% (n=241) made a sustained return to work within 2 years after fusion. To identify preoperative predictors of postoperative return to work status, the authors used multivariate logistic regression analysis, adjusting for many important covariates. These included prolonged time out of work (P<.001; odds ratio [OR], 0.24), psychiatric history (P<.001; OR, 0.14), prolonged use of opioid analgesics (P<.001; OR, 0.46), male sex (P=.014; OR, 0.65), and legal representation (P=.042; OR, 0.67). The return to work rates associated with these risk factors were 10.4%, 2.0%, 11.9%, 21.1%, and 20.7%, respectively. Of the study subjects, 76.8% (n=796) did not return to work and had considerably worse postoperative outcomes, highlighted by chronic opioid dependence and high rates of failed back syndrome, additional surgery, and new psychiatric comorbidity. The low return to work rates and other generally poor outcomes reported in this study may indicate a more limited role for lumbar fusion among patients with DDD who have workers' compensation claims. More studies are needed to determine whether fusion for DDD can improve function and quality of life in these patients. Copyright 2015, SLACK Incorporated.

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. (b...

The influence of ground conductivity on the structure of RF radiation from return strokes

NASA Technical Reports Server (NTRS)

Levine, D. M.; Gesell, L.

1984-01-01

The combination of the finite conductivity of the Earth plus the propagation of the return stroke current up the channel which results in an apparent time delay between the fast field changes and RF radiation for distant observers is shown. The time delay predicted from model return strokes is on the order of 20 micro and the received signal has the characteristics of the data observed in Virginia and Florida. A piecewise linear model for the return stroke channel and a transmission line model for current propagation on each segment was used. Radiation from each segment is calculated over a flat Earth with finite conductivity using asymptotics approximations for the Sommerfeld integrals. The radiation at the observer is processed by a model AM radio receiver. The output voltage was calculated for several frequencies between HF-UHF assuming a system bandwidth (300 kHz) characteristic of the system used to collect data in Florida and Virginia. Comparison with the theoretical fast field changes indicates a time delay of 20 microns.

In-hospital Breastfeeding and Intention to Return to Work Influence Mothers' Breastfeeding Intentions.

PubMed

Thomas-Jackson, Shera C; Bentley, Gail E; Keyton, Kristina; Reifman, Alan; Boylan, Mallory; Hart, Sybil L

2016-11-01

Research continues to demonstrate that formula feeding is associated with numerous long-term negative outcomes for a mother and her infant. However, many women cease breastfeeding sooner than intended and recommended. Breastfeeding has been found to be related to demographics, maternal mood, and returning to work outside the home. This study aimed to shed light on the woman's perception of the effect of working on intended breastfeeding duration. This study used intentions to return to work and in-hospital breastfeeding to predict breastfeeding intentions. Women (N = 160) were surveyed during the first 48 hours postdelivery of healthy, full-term infants. Survey instruments included demographics (socioeconomic status, maternal age, education, and marital status), depression, fetal attachment, current exclusive breastfeeding status, as well as breastfeeding and return-to-work intentions for the next year. A path analysis was used to explore relationships and predictors of breastfeeding intentions. The model had a good fit and breastfeeding intentions were predicted by exclusive breastfeeding in the hospital (β = 0.21, P < .01) and negatively predicted by return to work (β = -0.18, P < .05). Exclusive breastfeeding in the hospital within the first 48 hours postpartum and intention to return to work influence how long a mother intends to breastfeed. Attention to these areas can be provided immediately postpartum to support exclusive breastfeeding and provide informational support on continuing to breastfeed/express milk upon return to work if the mother intends to return to work.

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…

Land - Ocean Climate Linkages and the Human Evolution - New ICDP and IODP Drilling Initiatives in the East African Rift Valley and SW Indian Ocean

NASA Astrophysics Data System (ADS)

Zahn, R.; Feibel, C.; Co-Pis, Icdp/Iodp

2009-04-01

The past 5 Ma were marked by systematic shifts towards colder climates and concomitant reorganizations in ocean circulation and marine heat transports. Some of the changes involved plate-tectonic shifts such as the closure of the Panamanian Isthmus and restructuring of the Indonesian archipelago that affected inter-ocean communications and altered the world ocean circulation. These changes induced ocean-atmosphere feedbacks with consequences for climates globally and locally. Two new ICDP and IODP drilling initiatives target these developments from the perspectives of marine and terrestrial palaeoclimatology and the human evolution. The ICDP drilling initiative HSPDP ("Hominid Sites and Paleolakes Drilling Project"; ICDP ref. no. 10/07) targets lacustrine depocentres in Ethiopia (Hadar) and Kenya (West Turkana, Olorgesailie, Magadi) to retrieve sedimentary sequences close to the places and times where various species of hominins lived over currently available outcrop records. The records will provide a spatially resolved record of the East African environmental history in conjunction with climate variability at orbital (Milankovitch) and sub-orbital (ENSO decadal) time scales. HSPDP specifically aims at (1) compiling master chronologies for outcrops around each of the depocentres; (2) assessing which aspects of the paleoenvironmental records are a function of local origin (hydrology, hydrogeology) and which are linked with regional or larger-scale signals; (3) correlating broad-scale patterns of hominin phylogeny with the global beat of climate variability and (4) correlating regional shifts in the hominin fossil and archaeological record with more local patterns of paleoenvironmental change. Ultimately the aim is to test hypotheses that link physical and cultural adaptations in the course of the hominin evolution to local environmental change and variability. The IODP initiative SAFARI ("Southern African Climates, Agulhas Warm Water Transports and Retroflection

Induced charging of shuttle orbiter by high electron-beam currents

NASA Technical Reports Server (NTRS)

Liemohn, H. B.

1977-01-01

Emission of high-current electron beams that was proposed for some Spacelab payloads required substantial return currents to the orbiter skin in order to neutralize the beam charge. Since the outer skin of the vehicle was covered with approximately 1200 sq m of thermal insulation which has the dielectric quality of air and an electrical conductivity that was estimated by NASA at 10 to the -9 power to 10 to the -10 power mhos/m, considerable transient charging and local potential differences were anticipated across the insulation. The theory for induced charging of spacecraft due to operation of electron guns was only developed for spherical metal vehicles and constant emission currents, which were not directly applicable to the orbiter situation. Field-aligned collection of electron return current from the ambient ionosphere at orbiter altitudes provides up to approximately 150 mA on the conducting surfaces and approximately 2.4 A on the dielectric thermal insulation. Local ionization of the neutral atmosphere by energetic electron bombardment or electrical breakdown may provide somewhat more return current.

Return to Throwing after Shoulder or Elbow Injury.

PubMed

Sgroi, Terrance A; Zajac, John M

2018-03-01

Throwing places high demands on the human body, and specific characteristics are developed over time unique to these athletes. When returning to throw after injury, it is important to follow a criterion-based progression that allows the body to be prepared appropriately for the stresses that throwing will require. There is currently a void in the literature for criteria-based progression that helps these athletes return to the highest level of play. As injury rates continue to rise in baseball, there is increased evidence showing contributions of the core and lower extremity to the baseball pitch. There is also additional data showing pitcher specific characteristics such as range of motion and scapular position in this unique population. The rehab professional should take into account every phase of the pitch starting from balance through ball release when designing a comprehensive return-to-throwing program. Returning an athlete back to a throwing sport can be an overwhelming task. The rehabilitation specialist must have a sound understanding of the throwing motion as well as any biomechanical implications on the body, contributions throughout the kinetic chain, range of motion, and strength characteristics specific to the thrower as well as proper tissue loading principles. It is important that these athletes are not progressed too quickly through their programs and that a criteria-based progression is followed. They should have normalized range of motion, strength, and scapular mechanics, followed by a sound plyometric progression. Once this is achieved, they are advanced to an interval throwing program with increasing distance, effort, and volume which should be tracked for workload, making sure they do not throw more than their body is prepared for.

NASA's Planned Return to the Moon: Global Access and Anytime Return Requirement Implications on the Lunar Orbit Insertion Burns

NASA Technical Reports Server (NTRS)

Garn, Michelle; Qu, Min; Chrone, Jonathan; Su, Philip; Karlgaard, Chris

2008-01-01

Lunar orbit insertion LOI is a critical maneuver for any mission going to the Moon. Optimizing the geometry of this maneuver is crucial to the success of the architecture designed to return humans to the Moon. LOI burns necessary to meet current NASA Exploration Constellation architecture requirements for the lunar sortie missions are driven mainly by the requirement for global access and "anytime" return from the lunar surface. This paper begins by describing the Earth-Moon geometry which creates the worst case (delta)V for both the LOI and the translunar injection (TLI) maneuvers over the full metonic cycle. The trajectory which optimizes the overall (delta)V performance of the mission is identified, trade studies results covering the entire lunar globe are mapped onto the contour plots, and the effects of loitering in low lunar orbit as a means of reducing the insertion (delta)V are described. Finally, the lighting conditions on the lunar surface are combined with the LOI and TLI analyses to identify geometries with ideal lighting conditions at sites of interest which minimize the mission (delta)V.

26 CFR 1.1502-79A - Separate return years generally applicable for consolidated return years beginning before January...

Code of Federal Regulations, 2010 CFR

2010-04-01

... December 31, 1967. (ii) P, S, and T join in the filing of a consolidated return for 1968, which return... attributable to P and S. Even though S was not in existence in 1966, the portion attributable to S can be... return year and to the extent that it was absorbed in P's 1966 separate return year. The portion of the...

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) in...

Characteristics of donors who do or do not return to give blood and barriers to their return

PubMed Central

Wevers, Anne; Wigboldus, Daniël H.J.; de Kort, Wim L.A.M.; van Baaren, Rick; Veldhuizen, Ingrid J.T.

2014-01-01

Background In the Netherlands about 50% of whole blood donors return to give blood after an invitation to donate. This study aimed to investigate the characteristics of donor return behaviour and to gain insight into the barriers to blood donation reported by the donors themselves. Materials and methods A total of 4,901 whole blood donors were invited to donate in week 39 of 2009. Barriers mentioned by donors who informed the blood bank for not donating were registered for 1 month. Logistic regression analyses assessed relevant characteristics of return behaviour, such as age and blood type, in men and women separately. Results Of the invited donors, 55% returned to give a donation, whereas 45% did not return. Male donors were more likely to return when they were older, had a higher previous return rate and had no past deferrals. The same pattern was found among women, but was less strong. The main barriers were: time constraints (35%), preference to postpone donation due to general physical problems although being eligible to donate (29%), and being ineligible to donate due to medical deferral criteria (9%). Discussion Specific donor characteristics are associated with return behaviour. Not donating due to time constraints could mean that donors do not feel the urgency of donating blood. Interventions targeted to increase commitment among specific donor groups should be tested further. PMID:23522891

Characteristics of donors who do or do not return to give blood and barriers to their return.

PubMed

Wevers, Anne; Wigboldus, Daniël H J; de Kort, Wim L A M; van Baaren, Rick; Veldhuizen, Ingrid J T

2014-01-01

In the Netherlands about 50% of whole blood donors return to give blood after an invitation to donate. This study aimed to investigate the characteristics of donor return behaviour and to gain insight into the barriers to blood donation reported by the donors themselves. A total of 4,901 whole blood donors were invited to donate in week 39 of 2009. Barriers mentioned by donors who informed the blood bank for not donating were registered for 1 month. Logistic regression analyses assessed relevant characteristics of return behaviour, such as age and blood type, in men and women separately. Of the invited donors, 55% returned to give a donation, whereas 45% did not return. Male donors were more likely to return when they were older, had a higher previous return rate and had no past deferrals. The same pattern was found among women, but was less strong. The main barriers were: time constraints (35%), preference to postpone donation due to general physical problems although being eligible to donate (29%), and being ineligible to donate due to medical deferral criteria (9%). Specific donor characteristics are associated with return behaviour. Not donating due to time constraints could mean that donors do not feel the urgency of donating blood. Interventions targeted to increase commitment among specific donor groups should be tested further.

Return to Play After Liver and Spleen Trauma

PubMed Central

Juyia, Rushad F.; Kerr, Hamish A.

2014-01-01

Context: Sport-related spleen and liver injuries pose a challenge for the physician. Although rare, these injuries can have serious and even life-threatening outcomes if not accurately diagnosed and managed in a timely fashion. Currently, there are no evidence-based guidelines on duration and intensity of restricted activity and return to play after spleen and liver injury. In addition, there is controversy on follow-up imaging after injury. Evidence Acquisition: PubMed was searched using the terms splenic or spleen and trauma and hepatic or liver and trauma from 1980 to 2013. The citations from sentinel papers were also reviewed. Study Design: Clinical review. Level of Evidence: Level 3. Results: Ultrasound is ideal in the unstable athlete. Nonoperative management of blunt splenic and hepatic injuries is recommended for hemodynamically stable patients regardless of injury grade, patient age, or presence of associated injuries. Follow-up imaging is not routinely recommended unless clinically indicated. Athletes may engage in light activity for the first 3 months after injury and then gradual return to unrestricted activity as tolerated. High-level athletes may choose splenectomy or serial imaging for faster return to play. Conclusion: Intravenous contrast-enhanced computed tomography is the diagnostic imaging modality of choice in stable athletes with blunt abdominal trauma. Strength-of-Recommendation Taxonomy: C. PMID:24790694

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 record...

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 record...

Return-to-work coordination programmes for improving return to work in workers on sick leave.

PubMed

Vogel, Nicole; Schandelmaier, Stefan; Zumbrunn, Thomas; Ebrahim, Shanil; de Boer, Wout El; Busse, Jason W; Kunz, Regina

2017-03-30

To limit long-term sick leave and associated consequences, insurers, healthcare providers and employers provide programmes to facilitate disabled people's return to work. These programmes include a variety of coordinated and individualised interventions. Despite the increasing popularity of such programmes, their benefits remain uncertain. We conducted a systematic review to determine the long-term effectiveness of return-to-work coordination programmes compared to usual practice in workers at risk for long-term disability. To assess the effects of return-to-work coordination programmes versus usual practice for workers on sick leave or disability. We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 11), MEDLINE, Embase, CINAHL and PsycINFO up to 1 November 2016. We included randomised controlled trials (RCTs) that enrolled workers absent from work for at least four weeks and randomly assigned them to return-to-work coordination programmes or usual practice. Two review authors independently screened titles, abstracts and full-text articles for study eligibility; extracted data; and assessed risk of bias from eligible trials. We contacted authors for additional data where required. We conducted random-effects meta-analyses and used the GRADE approach to rate the quality of the evidence. We identified 14 studies from nine countries that enrolled 12,568 workers. Eleven studies focused on musculoskeletal problems, two on mental health and one on both. Most studies (11 of 14) followed workers 12 months or longer. Risk of bias was low in 10 and high in 4 studies, but findings were not sensitive to their exclusion.We found no benefits for return-to-work coordination programmes on return-to-work outcomes.For short-term follow-up of six months, we found no effect on time to return to work (hazard ratio (HR) 1.32, 95% confidence interval (CI) 0.93 to 1.88, low-quality evidence), cumulative sickness absence (mean difference (MD) -16.18 work

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…

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…

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

Code of Federal Regulations, 2011 CFR

2011-04-01

... 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 Internal...

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

... 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 Internal...

Understanding the multifractality in portfolio excess returns

NASA Astrophysics Data System (ADS)

Chen, Cheng; Wang, Yudong

2017-01-01

The multifractality in stock returns have been investigated extensively. However, whether the autocorrelations in portfolio returns are multifractal have not been considered in the literature. In this paper, we detect multifractal behavior of returns of portfolios constructed based on two popular trading rules, size and book-to-market (BM) ratio. Using the multifractal detrended fluctuation analysis, we find that the portfolio returns are significantly multifractal and the multifractality is mainly attributed to long-range dependence. We also investigate the multifractal cross-correlation between portfolio return and market average return using the detrended cross-correlation analysis. Our results show that the cross-correlations of small fluctuations are persistent, while those of large fluctuations are anti-persistent.

Cognitive work hardening: a return-to-work intervention for people with depression.

PubMed

Wisenthal, Adeena; Krupa, Terry

2013-01-01

Mental health claims in the workplace are rising, particularly those due to depression. Associated with this is an increase in disability costs for the employer and the disability insurer, but even more important is the human suffering that results. While treatments are available for the depression there is a gap in interventions that specifically target return-to-work preparation. This paper presents cognitive work hardening, a treatment intervention that can bridge this gap by addressing the unique functional issues inherent in depression with a view to increasing return-to-work success. Cognitive work hardening applies the proven principles of classical work hardening (which has typically been applied to people with physical injuries) to the mental health domain. This paper explains how the occupational therapy principle of occupation and the core competency, enablement, are utilized and applied in cognitive work hardening. Key skills of the occupational therapist are also discussed. In addition, the paper considers the relationship of cognitive work hardening to recovery and mental illness, and the role it plays among workplace-based return-to-work interventions in the current movement toward non-clinical return-to-work interventions.

26 CFR 301.6011-7 - Specified tax return preparers required to file individual income tax returns using magnetic media.

Code of Federal Regulations, 2014 CFR

2014-04-01

...-electronic (paper) form. Submission of an individual income tax return by a tax return preparer or a... otherwise delivering of the paper individual income tax return to the IRS by the preparer, any member...) that states the taxpayer chooses to file the individual income tax return in paper format, and that the...

Heterogeneity in Schooling Rates of Return

ERIC Educational Resources Information Center

Henderson, Daniel J.; Polachek, Solomon W.; Wang, Le

2011-01-01

This paper relaxes the assumption of homogeneous rates of return to schooling by employing nonparametric kernel regression. This approach allows us to examine the differences in rates of return to education both across and within groups. Similar to previous studies we find that on average blacks have higher returns to education than whites,…

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.

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 be...

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 be...

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 be...

Note on a modified return period scale for upper-truncated unbounded flood distributions

NASA Astrophysics Data System (ADS)

Bardsley, Earl

2017-01-01

Probability distributions unbounded to the right often give good fits to annual discharge maxima. However, all hydrological processes are in reality constrained by physical upper limits, though not necessarily well defined. A result of this contradiction is that for sufficiently small exceedance probabilities the unbounded distributions anticipate flood magnitudes which are impossibly large. This raises the question of whether displayed return period scales should, as is current practice, have some given number of years, such as 500 years, as the terminating rightmost tick-point. This carries the implication that the scale might be extended indefinitely to the right with a corresponding indefinite increase in flood magnitude. An alternative, suggested here, is to introduce a sufficiently high upper truncation point to the flood distribution and modify the return period scale accordingly. The rightmost tick-mark then becomes infinity, corresponding to the upper truncation point discharge. The truncation point is likely to be set as being above any physical upper bound and the return period scale will change only slightly over all practical return periods of operational interest. The rightmost infinity tick point is therefore proposed, not as an operational measure, but rather to signal in flood plots that the return period scale does not extend indefinitely to the right.

Return to Play After Partial Lateral Meniscectomy in National Football League Athletes.

PubMed

Aune, Kyle T; Andrews, James R; Dugas, Jeffrey R; Cain, E Lyle

2014-08-01

Lateral meniscal injury is a common and possibly career-threatening injury among players in the National Football League (NFL). The rate of return to play (RTP) and factors that affect RTP after lateral meniscal injury in NFL players are currently not defined. The aims of this study were to determine the rate of RTP to regular-season NFL game play of NFL players after arthroscopic partial lateral meniscectomy and to identify factors that can predict the ability to return to play. Case series; Level of evidence, 4. Seventy-two patients undergoing 77 arthroscopic lateral partial meniscectomies were followed to determine the rate of RTP (defined as successful RTP in at least 1 regular-season NFL game after meniscectomy) and factors predicting players' ability to return to play. Perioperative variables were recorded using retrospective chart review. Players' heights and weights, dates of return, draft rounds, and counts of games, starts, and seasons both before and after meniscectomy were all collected from statistical databases maintained by the NFL. Chi-square and Student t tests were performed to assess differences among covariates with respect to an athlete's ability to return to play, and odds ratios were calculated as appropriate. All percentages were calculated as percent of total procedures performed (n = 77). Of the 77 partial lateral meniscectomies performed, 61% (n = 47) resulted in the athlete returning to play at his previous level of competition with an average length of time to RTP of 8.5 months; 19 (40%) of those who returned were still active in the NFL at the time of follow-up. Age at time of surgery, games and seasons played before surgery, and individual position were not significantly different between those who did and did not return to play. Undergoing a concomitant procedure did not affect an athlete's ability to return to play, nor did concurrent arthroscopic anterior cruciate ligament reconstruction affect a player's likelihood to return to

26 CFR 40.6011(a)-1 - Returns.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 26 Internal Revenue 16 2010-04-01 2010-04-01 true Returns. 40.6011(a)-1 Section 40.6011(a)-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) MISCELLANEOUS EXCISE TAXES EXCISE TAX PROCEDURAL REGULATIONS § 40.6011(a)-1 Returns. (a) In general—(1) Return required. The return of any tax to which this part 40 applies...

Inhibition of return in the archer fish.

PubMed

Gabay, Shai; Leibovich, Tali; Ben-Simon, Avi; Henik, Avishai; Segev, Ronen

2013-01-01

Inhibition of return is the inhibitory tagging of recently attended locations or objects. It was previously suggested that inhibition of return is a foraging facilitator in visual search. Inhibition of return was first discovered in humans and was demonstrated also in monkeys, yet it has never been demonstrated in non-primates. Here we report the presence of inhibition of return in the archer fish, which shoots down prey on overhanging vegetation, using squirts of water spouted from its mouth. Moreover, we find similar attentional effects for fish as for human participants. Our results show that the generation of inhibition of return does not require a fully developed cortex and strengthen the view that inhibition of return functions as a foraging facilitator.

Old-Age Disability and Wealth among Return Mexican Migrants from the United States

PubMed Central

Wong, Rebeca; Gonzalez-Gonzalez, Cesar

2012-01-01

Objective To examine the old-age consequences of international migration with a focus on disability and wealth from the perspective of the origin country. Methods Analysis sample includes persons aged 60+ from the Mexican Health and Aging Study, a national survey of older-adults in Mexico in 2001. Univariate methods are used to present a comparative profile of return migrants. Multivariate models are estimated for physical disability and wealth. Results Gender differences are profound. Return migrant women are more likely to be disabled while men are wealthier than comparable older adults in Mexico. Discussion Compared to current older adults, younger cohorts of Mexico-U.S. migrants increasingly include women, and more migrants seem likely to remain in the United States rather than return, thus more research will be needed on the old-age conditions of migrants in both countries. PMID:20876848

Advanced Curation of Current and Future Extraterrestrial Samples

NASA Technical Reports Server (NTRS)

Allen, Carlton C.

2013-01-01

Curation of extraterrestrial samples is the critical interface between sample return missions and the international research community. Curation includes documentation, preservation, preparation, and distribution of samples. The current collections of extraterrestrial samples include: Lunar rocks / soils collected by the Apollo astronauts Meteorites, including samples of asteroids, the Moon, and Mars "Cosmic dust" (asteroid and comet particles) collected by high-altitude aircraft Solar wind atoms collected by the Genesis spacecraft Comet particles collected by the Stardust spacecraft Interstellar dust collected by the Stardust spacecraft Asteroid particles collected by the Hayabusa spacecraft These samples were formed in environments strikingly different from that on Earth. Terrestrial contamination can destroy much of the scientific significance of many extraterrestrial materials. In order to preserve the research value of these precious samples, contamination must be minimized, understood, and documented. In addition the samples must be preserved - as far as possible - from physical and chemical alteration. In 2011 NASA selected the OSIRIS-REx mission, designed to return samples from the primitive asteroid 1999 RQ36 (Bennu). JAXA will sample C-class asteroid 1999 JU3 with the Hayabusa-2 mission. ESA is considering the near-Earth asteroid sample return mission Marco Polo-R. The Decadal Survey listed the first lander in a Mars sample return campaign as its highest priority flagship-class mission, with sample return from the South Pole-Aitken basin and the surface of a comet among additional top priorities. The latest NASA budget proposal includes a mission to capture a 5-10 m asteroid and return it to the vicinity of the Moon as a target for future sampling. Samples, tools, containers, and contamination witness materials from any of these missions carry unique requirements for acquisition and curation. Some of these requirements represent significant advances over

A new framework for estimating return levels using regional frequency analysis

NASA Astrophysics Data System (ADS)

Winter, Hugo; Bernardara, Pietro; Clegg, Georgina

2017-04-01

We propose a new framework for incorporating more spatial and temporal information into the estimation of extreme return levels. Currently, most studies use extreme value models applied to data from a single site; an approach which is inefficient statistically and leads to return level estimates that are less physically realistic. We aim to highlight the benefits that could be obtained by using methodology based upon regional frequency analysis as opposed to classic single site extreme value analysis. This motivates a shift in thinking, which permits the evaluation of local and regional effects and makes use of the wide variety of data that are now available on high temporal and spatial resolutions. The recent winter storms over the UK during the winters of 2013-14 and 2015-16, which have caused wide-ranging disruption and damaged important infrastructure, provide the main motivation for the current work. One of the most impactful natural hazards is flooding, which is often initiated by extreme precipitation. In this presentation, we focus on extreme rainfall, but shall discuss other meteorological variables alongside potentially damaging hazard combinations. To understand the risks posed by extreme precipitation, we need reliable statistical models which can be used to estimate quantities such as the T-year return level, i.e. the level which is expected to be exceeded once every T-years. Extreme value theory provides the main collection of statistical models that can be used to estimate the risks posed by extreme precipitation events. Broadly, at a single site, a statistical model is fitted to exceedances of a high threshold and the model is used to extrapolate to levels beyond the range of the observed data. However, when we have data at many sites over a spatial domain, fitting a separate model for each separate site makes little sense and it would be better if we could incorporate all this information to improve the reliability of return level estimates. Here

Return to sports after shoulder arthroplasty

PubMed Central

Johnson, Christine C; Johnson, Daniel J; Liu, Joseph N; Dines, Joshua S; Dines, David M; Gulotta, Lawrence V; Garcia, Grant H

2016-01-01

Many patients prioritize the ability to return to sports following shoulder replacement surgeries, including total shoulder arthroplasty (TSA), reverse total shoulder arthroplasty (RTSA), and hemiarthroplasty (HA). While activity levels after hip and knee replacements have been well-established in the literature, studies on this topic in the field of shoulder arthroplasty are relatively limited. A review of the literature regarding athletic activity after shoulder arthroplasty was performed using the PubMed database. All studies relevant to shoulder arthroplasty and return to sport were included. The majority of patients returned to their prior level of activity within six months following TSA, RTSA, and shoulder HA. Noncontact, low demand activities are permitted by most surgeons postoperatively and generally have higher return rates than contact sports or high-demand activities. In some series, patients reported an improvement in their ability to participate in sports following the arthroplasty procedure. The rates of return to sports following TSA (75%-100%) are slightly higher than those reported for HA (67%-76%) and RTSA (75%-85%). Patients undergoing TSA, RTSA, and shoulder HA should be counseled that there is a high probability that they will be able to return to their preoperative activity level within six months postoperatively. TSA has been associated with higher rates of return to sports than RTSA and HA, although this may reflect differences in patient population or surgical indication. PMID:27672564

Auroral Current and Electrodynamics Structure (ACES) Observations of Ionospheric Feedback in the Alfven Resonator

NASA Technical Reports Server (NTRS)

Cohen, Ian J.; Lessard, Marc; Lund, Eric J.; Bounds, Scott R.; Kletzing, Craig; Kaeppler, Stephen R.; Sigsbee, Kristine M.; Streltsov, Anatoly V.; Labelle, James W.; Dombrowski, Micah P.;

A Qualitative Investigation of Return to Sport After Arthroscopic Bankart Repair: Beyond Stability.

PubMed

Tjong, Vehniah K; Devitt, Brian M; Murnaghan, M Lucas; Ogilvie-Harris, Darrell J; Theodoropoulos, John S

2015-08-01

Arthroscopic shoulder stabilization is known to have excellent functional results, but many patients do not return to their preinjury level of sport, with return to play rates reported between 48% and 100% despite good outcome scores. To understand specific subjective psychosocial factors influencing a patient's decision to return to sport after arthroscopic shoulder stabilization. Case series; Level of evidence, 4. Semistructured qualitative interviews were conducted with patients aged 18 to 40 years who had undergone primary arthroscopic shoulder stabilization and had a minimum 2-year follow-up. All patients participated in sport before surgery without any further revision operations or shoulder injuries. Qualitative data analysis was performed in accordance with the Strauss and Corbin theory to derive codes, categories, and themes. Preinjury and current sport participation was defined by type, level of competition, and the Brophy/Marx shoulder activity score. Patient-reported pain and shoulder function were also obtained. A total of 25 patients were interviewed, revealing that fear of reinjury, shifts in priority, mood, social support, and self-motivation were found to greatly influence the decision to return to sport both in patients who had and had not returned to their preinjury level of play. Patients also described fear of sporting incompetence, self-awareness issues, recommendations from physical therapists, and degree of confidence as less common considerations affecting their return to sport. In spite of excellent functional outcomes, extrinsic and intrinsic factors such as competing interests, kinesiophobia, age, and internal stressors and motivators can have a major effect on a patient's decision to return to sport after arthroscopic shoulder stabilization. The qualitative methods used in this study provide a unique patient-derived perspective into postoperative recovery and highlight the necessity to recognize and address subjective and psychosocial

Automated Studies of Continuing Current in Lightning Flashes

NASA Astrophysics Data System (ADS)

Martinez-Claros, Jose

Continuing current (CC) is a continuous luminosity in the lightning channel that lasts longer than 10 ms following a lightning return stroke to ground. Lightning flashes following CC are associated with direct damage to power lines and are thought to be responsible for causing lightning-induced forest fires. The development of an algorithm that automates continuing current detection by combining NLDN (National Lightning Detection Network) and LEFA (Langmuir Electric Field Array) datasets for CG flashes will be discussed. The algorithm was applied to thousands of cloud-to-ground (CG) flashes within 40 km of Langmuir Lab, New Mexico measured during the 2013 monsoon season. It counts the number of flashes in a single minute of data and the number of return strokes of an individual lightning flash; records the time and location of each return stroke; performs peak analysis on E-field data, and uses the slope of interstroke interval (ISI) E-field data fits to recognize whether continuing current (CC) exists within the interval. Following CC detection, duration and magnitude are measured. The longest observed C in 5588 flashes was 631 ms. The performance of the algorithm (vs. human judgement) was checked on 100 flashes. At best, the reported algorithm is "correct" 80% of the time, where correct means that multiple stations agree with each other and with a human on both the presence and duration of CC. Of the 100 flashes that were validated against human judgement, 62% were hybrid. Automated analysis detects the first but misses the second return stroke in many cases where the second return stroke is followed by long CC. This problem is also present in human interpretation of field change records.

27 CFR 25.164 - Quarterly and semimonthly returns.

Code of Federal Regulations, 2010 CFR

2010-04-01

... BUREAU, DEPARTMENT OF THE TREASURY LIQUORS BEER Tax on Beer Preparation and Remittance of Tax Returns... on beer (unless prepaid) by return on Form 5000.24. The brewer shall file Form 5000.24 as a return... file a return on Form 5000.24 for each return period even though no beer was removed for consumption or...

26 CFR 301.6019-1 - Gift tax returns.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 26 Internal Revenue 18 2010-04-01 2010-04-01 false Gift tax returns. 301.6019-1 Section 301.6019-1... ADMINISTRATION PROCEDURE AND ADMINISTRATION Information and Returns Returns and Records § 301.6019-1 Gift tax returns. For provisions relating to requirement of gift tax returns, see §§ 25.6019-1 to 25.6019-4...

27 CFR 25.164 - Quarterly and semimonthly returns.

Code of Federal Regulations, 2012 CFR

2012-04-01

... BUREAU, DEPARTMENT OF THE TREASURY LIQUORS BEER Tax on Beer Preparation and Remittance of Tax Returns... on beer (unless prepaid) by return on Form 5000.24. The brewer shall file Form 5000.24 as a return... file a return on Form 5000.24 for each return period even though no beer was removed for consumption or...

27 CFR 25.164 - Quarterly and semimonthly returns.

Code of Federal Regulations, 2014 CFR

2014-04-01

... BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL BEER Tax on Beer Preparation and Remittance of Tax Returns... on beer (unless prepaid) by return on Form 5000.24. The brewer shall file Form 5000.24 as a return... file a return on Form 5000.24 for each return period even though no beer was removed for consumption or...

27 CFR 25.164 - Quarterly and semimonthly returns.

Code of Federal Regulations, 2013 CFR

2013-04-01

... BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL BEER Tax on Beer Preparation and Remittance of Tax Returns... on beer (unless prepaid) by return on Form 5000.24. The brewer shall file Form 5000.24 as a return... file a return on Form 5000.24 for each return period even though no beer was removed for consumption or...

27 CFR 25.164 - Quarterly and semimonthly returns.

Code of Federal Regulations, 2011 CFR

2011-04-01

... BUREAU, DEPARTMENT OF THE TREASURY LIQUORS BEER Tax on Beer Preparation and Remittance of Tax Returns... on beer (unless prepaid) by return on Form 5000.24. The brewer shall file Form 5000.24 as a return... file a return on Form 5000.24 for each return period even though no beer was removed for consumption or...

Pediatric Return to Sports After Spinal Surgery.

PubMed

Christman, Tyler; Li, Ying

2016-07-01

Pediatric patients who undergo spinal surgery are frequently involved in sporting activities. Return to play is often an important postoperative concern for the patient and family. A PubMed search was conducted for articles in the English language on return to play after treatment of pediatric acute disc herniation, degenerative disc disease, spondylolysis, spondylolisthesis, and scoliosis from 1980 to 2015. Reference lists were reviewed for additional pertinent articles. We included articles that focused on return to sports after surgical treatment of these conditions in this review. Clinical review. Level 4. There are no published guidelines, and most of the literature in this area has focused on return to play after spinal injury rather than after spinal surgery. Most children and adolescents have excellent outcomes with minimal pain at 1 year after lumbar discectomy. The majority of surgeons allow return to full activity once pain-free range of motion and strength are regained, typically at 8 to 12 weeks postoperatively. Pediatric patients with spondylolysis have good outcomes after direct pars repair. Satisfactory outcomes have been demonstrated after fusion for low- and high-grade spondylolisthesis. Most surgeons allow return to noncontact sports by 6 months after surgical treatment of spondylolysis and spondylolisthesis. Return to contact and collision sports is controversial. After posterior spinal fusion for scoliosis, most surgeons allow return to noncontact sports by 3 months and return to contact sports between 6 months and 1 year. Return to collision sports is controversial. There is little evidence to guide practitioners on return to sports after pediatric spinal surgery. Ultimately, the decision to allow any young athlete to resume sports participation after spinal injury or surgery must be individualized. © 2016 The Author(s).

Pediatric Return to Sports After Spinal Surgery

PubMed Central

Christman, Tyler; Li, Ying

2016-01-01

Context: Pediatric patients who undergo spinal surgery are frequently involved in sporting activities. Return to play is often an important postoperative concern for the patient and family. Evidence Acquisition: A PubMed search was conducted for articles in the English language on return to play after treatment of pediatric acute disc herniation, degenerative disc disease, spondylolysis, spondylolisthesis, and scoliosis from 1980 to 2015. Reference lists were reviewed for additional pertinent articles. We included articles that focused on return to sports after surgical treatment of these conditions in this review. Study Design: Clinical review. Level of Evidence: Level 4. Results: There are no published guidelines, and most of the literature in this area has focused on return to play after spinal injury rather than after spinal surgery. Most children and adolescents have excellent outcomes with minimal pain at 1 year after lumbar discectomy. The majority of surgeons allow return to full activity once pain-free range of motion and strength are regained, typically at 8 to 12 weeks postoperatively. Pediatric patients with spondylolysis have good outcomes after direct pars repair. Satisfactory outcomes have been demonstrated after fusion for low- and high-grade spondylolisthesis. Most surgeons allow return to noncontact sports by 6 months after surgical treatment of spondylolysis and spondylolisthesis. Return to contact and collision sports is controversial. After posterior spinal fusion for scoliosis, most surgeons allow return to noncontact sports by 3 months and return to contact sports between 6 months and 1 year. Return to collision sports is controversial. Conclusion: There is little evidence to guide practitioners on return to sports after pediatric spinal surgery. Ultimately, the decision to allow any young athlete to resume sports participation after spinal injury or surgery must be individualized. PMID:26920125

Technology Development and Advanced Planning for Curation of Returned Mars Samples

NASA Technical Reports Server (NTRS)

Lindstrom, David J.; Allen, Carlton C.

2002-01-01

NASA Johnson Space Center (JSC) curates extraterrestrial samples, providing the international science community with lunar rock and soil returned by the Apollo astronauts, meteorites collected in Antarctica, cosmic dust collected in the stratosphere, and hardware exposed to the space environment. Curation comprises initial characterization of new samples, preparation and allocation of samples for research, and clean, secure long-term storage. The foundations of this effort are the specialized cleanrooms (class 10 to 10,000) for each of the four types of materials, the supporting facilities, and the people, many of whom have been doing detailed work in clean environments for decades. JSC is also preparing to curate the next generation of extraterrestrial samples. These include samples collected from the solar wind, a comet, and an asteroid. Early planning and R\\&D are underway to support post-mission sample handling and curation of samples returned from Mars. One of the strong scientific reasons for returning samples from Mars is to search for evidence of current or past life in the samples. Because of the remote possibility that the samples may contain life forms that are hazardous to the terrestrial biosphere, the National Research Council has recommended that all samples returned from Mars be kept under strict biological containment until tests show that they can safely be released to other laboratories. It is possible that Mars samples may contain only scarce or subtle traces of life or prebiotic chemistry that could readily be overwhelmed by terrestrial contamination . Thus, the facilities used to contain, process, and analyze samples from Mars must have a combination of high-level biocontainment and organic / inorganic chemical cleanliness that is unprecedented. JSC has been conducting feasibility studies and developing designs for a sample receiving facility that would offer biocontainment at least the equivalent of current maximum containment BSL-4 (Bio

Technology Development and Advanced Planning for Curation of Returned Mars Samples

NASA Astrophysics Data System (ADS)

Lindstrom, D. J.; Allen, C. C.

2002-05-01

NASA/Johnson Space Center (JSC) curates extraterrestrial samples, providing the international science community with lunar rock and soil returned by the Apollo astronauts, meteorites collected in Antarctica, cosmic dust collected in the stratosphere, and hardware exposed to the space environment. Curation comprises initial characterization of new samples, preparation and allocation of samples for research, and clean, secure long-term storage. The foundations of this effort are the specialized cleanrooms (class 10 to 10,000) for each of the four types of materials, the supporting facilities, and the people, many of whom have been doing detailed work in clean environments for decades. JSC is also preparing to curate the next generation of extraterrestrial samples. These include samples collected from the solar wind, a comet, and an asteroid. Early planning and R&D are underway to support post-mission sample handling and curation of samples returned from Mars. One of the strong scientific reasons for returning samples from Mars is to search for evidence of current or past life in the samples. Because of the remote possibility that the samples may contain life forms that are hazardous to the terrestrial biosphere, the National Research Council has recommended that all samples returned from Mars be kept under strict biological containment until tests show that they can safely be released to other laboratories. It is possible that Mars samples may contain only scarce or subtle traces of life or prebiotic chemistry that could readily be overwhelmed by terrestrial contamination. Thus, the facilities used to contain, process, and analyze samples from Mars must have a combination of high-level biocontainment and organic / inorganic chemical cleanliness that is unprecedented. JSC has been conducting feasibility studies and developing designs for a sample receiving facility that would offer biocontainment at least the equivalent of current maximum containment BSL-4 (Bio

Lightning Strike Peak Current Probabilities as Related to Space Shuttle Operations

NASA Technical Reports Server (NTRS)

Johnson, Dale L.; Vaughan, William W.

2000-01-01

A summary is presented of basic lightning characteristics/criteria applicable to current and future aerospace vehicles. The paper provides estimates on the probability of occurrence of a 200 kA peak lightning return current, should lightning strike an aerospace vehicle in various operational phases, i.e., roll-out, on-pad, launch, reenter/land, and return-to-launch site. A literature search was conducted for previous work concerning occurrence and measurement of peak lighting currents, modeling, and estimating the probabilities of launch vehicles/objects being struck by lightning. This paper presents a summary of these results.

[Return to Work after Fractures of the Pelvis and the Acetabulum].

PubMed

Nusser, M; Holstiege, J; Kaluscha, R; Tepohl, L; Stuby, F; Röderer, G; Krischak, G

2015-06-01

Pelvic and acetabular fractures are severe injuries with serious consequences that mainly happen to young people. Therefore it is highly interesting to find out to what extent affected patients succeed in returning to work, which is an important factor concerning quality of live. Thus, the objective of this study was to estimate the "return to work" in a two-year follow-up after rehabilitative treatment of patients with pelvic and acetabular fractures and to identify influencing factors. A retrospective cohort study was conducted using population-based administrative data of the Baden-Württemberg statutory pension fund. All patients (age 18 to 63 years) who had participated in a rehabilitation programme between 2004 and 2009 due to a pelvic or acetabular fracture were included. Return to work was modelled using multivariate logistic regression analysis. Rehabilitants were classified as "returned" if they have paid at least one monthly contribution due to employment during 13 to 24 months after rehabilitation. Age, gender, diagnostic group, type of rehabilitation programme, fractures of the spine, nerve injuries of the lumbosacral area and/or the lower limb and employment status before the fractures were considered as prognostic covariates. Two-thirds of the 249 researched patients returned to work. This corresponds to a reduction of employment amounting to 16.6 % for patients with a pelvic fracture and 20.8 % for patients with an acetabular fracture. Main predictor for a return to work was the employment status before the fracture. Younger patients had a better chance to return to work than older ones. Patients with fractures of the spine or nerve injuries of the lumbosacral area and/or the lower limb had a 73 % or, respectively, 78 % higher risk of not returning to work. Fractures of the pelvis and the acetabulum currently lead in one of five patients to loss of employment. Thereby the trauma threatens the social security of the young patients. Follow

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.

Return to Golf After Lumbar Fusion.

PubMed

Shifflett, Grant D; Hellman, Michael D; Louie, Philip K; Mikhail, Christopher; Park, Kevin U; Phillips, Frank M

Spinal fusion surgery is being increasingly performed, yet few studies have focused on return to recreational sports after lumbar fusion and none have specifically analyzed return to golf. Most golfers successfully return to sport after lumbar fusion surgery. Case series. Level 4. All patients who underwent 1- or 2-level primary lumbar fusion surgery for degenerative pathologies performed by a single surgeon between January 2008 and October 2012 and had at least 1-year follow-up were included. Patients completed a specifically designed golf survey. Surveys were mailed, given during follow-up clinic, or answered during telephone contact. A total of 353 patients met the inclusion and exclusion criteria, with 200 responses (57%) to the questionnaire producing 34 golfers. The average age of golfers was 57 years (range, 32-79 years). In 79% of golfers, preoperative back and/or leg pain significantly affected their ability to play golf. Within 1 year from surgery, 65% of patients returned to practice and 52% returned to course play. Only 29% of patients stated that continued back/leg pain limited their play. Twenty-five patients (77%) were able to play the same amount of golf or more than before fusion surgery. Of those providing handicaps, 12 (80%) reported the same or an improved handicap. More than 50% of golfers return to on-course play within 1 year of lumbar fusion surgery. The majority of golfers can return to preoperative levels in terms of performance (handicap) and frequency of play. This investigation offers insight into when golfers return to sport after lumbar fusion surgery and provides surgeons with information to set realistic expectations postoperatively.

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 such...

The changes on physical characteristics of lightning discharge plasma during individual return stroke process

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

Xu, He; Yuan, Ping; Cen, Jian-Yong

2014-03-15

A cloud-to-ground lightning with six return strokes has been recorded with a slit-less spectrograph in Qinghai province. According to the spectra of return strokes without continuous current, the electron density, the channel temperature, and the gas pressure have been calculated. Then, the correlativity of these parameters has been analyzed. The results indicate that the total intensity of spectra is positive correlated to the intensity of spectral line, they both decrease with time rapidly; furthermore, the channel temperature and the gas pressure decrease with time slowly in the similar trends.

Oil-return characteristics of refrigerant oils in split heat pump system

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

Sundaresan, S.G.; Radermacher, R.

1996-08-01

Currently, HFC substitute refrigerants for R-22 are being evaluated in air-conditioning and heat pump applications. The oil return characteristics and heat transfer effects of the lubricants are being studied again. Based on commercial refrigeration experience POEs are the lubricants of choice for HFC refrigerants. POEs have two major drawbacks: hygroscopicity and high cost. Thus the question is raised to what extent is it possible to replace POEs with a lower cost, but immiscible, oil such as mineral oil. It is the purpose of this study to experimentally investigate the oil return behavior of R-407C with mineral oil in a splitmore » three-ton heat pump in comparison to R407C/POE and R-22/Mineral Oil.« less

Does Aggregated Returns Disclosure Increase Portfolio Risk Taking?

PubMed

Beshears, John; Choi, James J; Laibson, David; Madrian, Brigitte C

2017-06-01

Many experiments have found that participants take more investment risk if they see returns less frequently, see portfolio-level returns (rather than each individual asset's returns), or see long-horizon (rather than one-year) historical return distributions. In contrast, we find that such information aggregation treatments do not affect total equity investment when we make the investment environment more realistic than in prior experiments. Previously documented aggregation effects are not robust to changes in the risky asset's return distribution or the introduction of a multi-day delay between portfolio choice and return realizations.

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…

Demographic, psychometric, and case progression information as predictors of return-to-work in teachers undergoing occupational rehabilitation.

PubMed

Young, A E; Russell, J

1995-12-01

Occupational stress is a significant problem and is of particular concern for educational organizations. It was the aim of the current project to identify variables that could predict return-to-work outcomes in a group of teachers who had taken leave for a work-related stress condition. Demographic, psychometric, and case progression data were collected for 119 teachers who had taken Workers' Compensation Leave and were participating in a rehabilitation program. The participants' return to work outcomes were followed-up at least 12 months after they initially left their workplace. Hierarchical discriminant function analysis indicated that 84.62% of the cases could be correctly classified as either "returning to work" or "not returning to work due to illness." The main predictor variables were: if the individual had attempted to return to work within 505 days of injury, the individual's health behaviors, the sex of the individual, and the type of school in which he or she was employed (primary or secondary). It is suggested that the derived model could be further developed and used to predict return to work from stress-related illnesses.

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

Code of Federal Regulations, 2010 CFR

2010-04-01

... telephone conversation with Internal Revenue Service officials. (iii) As long as the requirements of this... telephone conversation, for disclosures of returns and return information to be made to the other person. (3...

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

... telephone conversation with Internal Revenue Service officials. (iii) As long as the requirements of this... telephone conversation, for disclosures of returns and return information to be made to the other person. (3...

A systematic review of studies identifying predictors of poor return to work outcomes following workplace injury.

PubMed

Street, Tamara D; Lacey, Sarah J

2015-06-05

Injuries occurring in the workplace can have serious implications for the health of the individual, the productivity of the employer and the overall economic community. The objective of this paper is to increase the current state of understanding of individual demographic and psychosocial characteristics associated with extended absenteeism from the workforce due to a workplace injury. Studies included in this systematic literature review tracked participants' return to work status over a minimum of three months, identified either demographic, psychosocial or general injury predictors of poor return to work outcomes and included a heterogeneous sample of workplace injuries. Identified predictors of poor return to work outcomes included older age, female gender, divorced marital status, two or more dependent family members, lower education levels, employment variables associated with reduced labour market desirability, severity or sensitive injury locations, negative attitudes and outcome perceptions of the participant. There is a need for clear and consistent definition and measurement of return to work outcomes and a holistic theoretical model integrating injury, psychosocial and demographic predictors of return to work. Through greater understanding of the nature of factors affecting return to work, improved outcomes could be achieved.

Return to sports after surgery to correct adolescent idiopathic scoliosis: a survey of the Spinal Deformity Study Group.

PubMed

Lehman, Ronald A; Kang, Daniel G; Lenke, Lawrence G; Sucato, Daniel J; Bevevino, Adam J

2015-05-01

There are no guidelines for when surgeons should allow patients to return to sports and athletic activities after spinal fusion for adolescent idiopathic scoliosis (AIS). Current recommendations are based on anecdotal reports and a survey performed more than a decade ago in the era of first/second-generation posterior implants. To identify current recommendations for return to sports and athletic activities after surgery for AIS. Questionnaire-based survey. Adolescent idiopathic scoliosis after corrective surgery. Type and time to return to sports. A survey was administered to members of the Spinal Deformity Study Group. The survey consisted of surgeon demographic information, six clinical case scenarios, three different construct types (hooks, pedicle screws, hybrid), and questions regarding the influence of lowest instrumented vertebra (LIV) and postoperative physical therapy. Twenty-three surgeons completed the survey, and respondents were all experienced expert deformity surgeons. Pedicle screw instrumentation allows earlier return to noncontact and contact sports, with most patients allowed to return to running by 3 months, both noncontact and contact sports by 6 months, and collision sports by 12 months postoperatively. For all construct types, approximately 20% never allow return to collision sports, whereas all surgeons allow eventual return to contact and noncontact sports regardless of construct type. In addition to construct type, we found progressively distal LIV resulted in more surgeons never allowing return to collision sports, with 12% for selective thoracic fusion to T12/L1 versus 33% for posterior spinal fusion to L4. Most respondents also did not recommend formal postoperative physical therapy (78%). Of all surgeons surveyed, there was only one reported instrumentation failure/pullout without neurologic deficit after a patient went snowboarding 2 weeks postoperatively. Modern posterior instrumentation allows surgeons to recommend earlier return

Work-Related Factors Considered by Sickness-Absent Employees When Estimating Timeframes for Returning to Work

PubMed Central

Choi, YoonSun

2016-01-01

Introduction Work-related factors have been found to be influential in shaping a number of return-to-work outcomes including return-to-work expectations. Based on the idea that work-related factors have the potential for modification through workplace-based initiatives, this study involved a detailed examination of work-related factors referenced by workers as being taken into consideration when estimating timeframes for returning to work. Methods Focus groups were conducted with 30 employees, currently off work (≤ 3 months) due to a musculoskeletal condition. During the focus groups, participants wrote and spoke about the factors that they considered when forming their expectations for returning to work. Data were subjected to thematic content analysis. Results Discussions revealed that participants’ considerations tended to differ depending on whether or not they had a job to return to. Those with jobs (n = 23) referenced specific influences such as working relationships, accommodations, physical and practical limitations, as well as concerns about their ability to do their job. Those without a job to return to (n = 7) talked about the ways they would go about finding work, and how long they thought this would take. Both groups mentioned the influence of wanting to find the “right” job, retraining and being limited due to the need for income. Conclusion Findings indicate that employees reference numerous work-related factors when estimating their timeframes for returning to work, and that many of these have been previously identified as relating to other return-to-work outcomes. Findings suggest the potential to improve return-to-work expectation through addressing work-related influences, and helping people work through the tasks they need to complete in order to move forward in the return-to-work process. PMID:27706194

Work-Related Factors Considered by Sickness-Absent Employees When Estimating Timeframes for Returning to Work.

PubMed

Young, Amanda E; Choi, YoonSun

2016-01-01

Work-related factors have been found to be influential in shaping a number of return-to-work outcomes including return-to-work expectations. Based on the idea that work-related factors have the potential for modification through workplace-based initiatives, this study involved a detailed examination of work-related factors referenced by workers as being taken into consideration when estimating timeframes for returning to work. Focus groups were conducted with 30 employees, currently off work (≤ 3 months) due to a musculoskeletal condition. During the focus groups, participants wrote and spoke about the factors that they considered when forming their expectations for returning to work. Data were subjected to thematic content analysis. Discussions revealed that participants' considerations tended to differ depending on whether or not they had a job to return to. Those with jobs (n = 23) referenced specific influences such as working relationships, accommodations, physical and practical limitations, as well as concerns about their ability to do their job. Those without a job to return to (n = 7) talked about the ways they would go about finding work, and how long they thought this would take. Both groups mentioned the influence of wanting to find the "right" job, retraining and being limited due to the need for income. Findings indicate that employees reference numerous work-related factors when estimating their timeframes for returning to work, and that many of these have been previously identified as relating to other return-to-work outcomes. Findings suggest the potential to improve return-to-work expectation through addressing work-related influences, and helping people work through the tasks they need to complete in order to move forward in the return-to-work process.

Return to Golf After Lumbar Fusion

PubMed Central

Shifflett, Grant D.; Hellman, Michael D.; Louie, Philip K.; Mikhail, Christopher; Park, Kevin U.; Phillips, Frank M.

2016-01-01

Background: Spinal fusion surgery is being increasingly performed, yet few studies have focused on return to recreational sports after lumbar fusion and none have specifically analyzed return to golf. Hypothesis: Most golfers successfully return to sport after lumbar fusion surgery. Study Design: Case series. Level of Evidence: Level 4. Methods: All patients who underwent 1- or 2-level primary lumbar fusion surgery for degenerative pathologies performed by a single surgeon between January 2008 and October 2012 and had at least 1-year follow-up were included. Patients completed a specifically designed golf survey. Surveys were mailed, given during follow-up clinic, or answered during telephone contact. Results: A total of 353 patients met the inclusion and exclusion criteria, with 200 responses (57%) to the questionnaire producing 34 golfers. The average age of golfers was 57 years (range, 32-79 years). In 79% of golfers, preoperative back and/or leg pain significantly affected their ability to play golf. Within 1 year from surgery, 65% of patients returned to practice and 52% returned to course play. Only 29% of patients stated that continued back/leg pain limited their play. Twenty-five patients (77%) were able to play the same amount of golf or more than before fusion surgery. Of those providing handicaps, 12 (80%) reported the same or an improved handicap. Conclusion: More than 50% of golfers return to on-course play within 1 year of lumbar fusion surgery. The majority of golfers can return to preoperative levels in terms of performance (handicap) and frequency of play. Clinical Relevance: This investigation offers insight into when golfers return to sport after lumbar fusion surgery and provides surgeons with information to set realistic expectations postoperatively. PMID:27879299

Groundbreaking Mars Sample Return for Science and Human Exploration

NASA Technical Reports Server (NTRS)

Cohen, Barbara; Draper, David; Eppler, Dean; Treiman, Allan

2012-01-01

Partnerships between science and human exploration have recent heritage for the Moon (Lunar Precursor Robotics Program, LPRP) and nearearth objects (Exploration Precursor Robotics Program, xPRP). Both programs spent appreciable time and effort determining measurements needed or desired before human missions to these destinations. These measurements may be crucial to human health or spacecraft design, or may be desired to better optimize systems designs such as spacesuits or operations. Both LPRP and xPRP recommended measurements from orbit, by landed missions and by sample return. LPRP conducted the Lunar Reconnaissance Orbiter (LRO) and Lunar Crater Observation and Sensing Satellite (LCROSS) missions, providing high-resolution visible imagery, surface and subsurface temperatures, global topography, mapping of possible water ice deposits, and the biological effects of radiation [1]. LPRP also initiated a landed mission to provide dust and regolith properties, local lighting conditions, assessment of resources, and demonstration of precision landing [2]. This mission was canceled in 2006 due to funding shortfalls. For the Moon, adequate samples of rocks and regolith were returned by the Apollo and Luna programs to conduct needed investigations. Many near-earth asteroids (NEAs) have been observed from the Earth and several have been more extensively characterized by close-flying missions and landings (NEAR, Hayabusa, Rosetta). The current Joint Robotic Precursor Activity program is considering activities such as partnering with the New Frontiers mission OSIRIS-Rex to visit a NEA and return a sample to the Earth. However, a strong consensus of the NEO User Team within xPRP was that a dedicated mission to the asteroid targeted by humans is required [3], ideally including regolith sample return for more extensive characterization and testing on the Earth.

An Integrated Tool for System Analysis of Sample Return Vehicles

NASA Technical Reports Server (NTRS)

Samareh, Jamshid A.; Maddock, Robert W.; Winski, Richard G.

2012-01-01

The next important step in space exploration is the return of sample materials from extraterrestrial locations to Earth for analysis. Most mission concepts that return sample material to Earth share one common element: an Earth entry vehicle. The analysis and design of entry vehicles is multidisciplinary in nature, requiring the application of mass sizing, flight mechanics, aerodynamics, aerothermodynamics, thermal analysis, structural analysis, and impact analysis tools. Integration of a multidisciplinary problem is a challenging task; the execution process and data transfer among disciplines should be automated and consistent. This paper describes an integrated analysis tool for the design and sizing of an Earth entry vehicle. The current tool includes the following disciplines: mass sizing, flight mechanics, aerodynamics, aerothermodynamics, and impact analysis tools. Python and Java languages are used for integration. Results are presented and compared with the results from previous studies.

Does Aggregated Returns Disclosure Increase Portfolio Risk Taking?

PubMed Central

Beshears, John; Choi, James J.; Laibson, David; Madrian, Brigitte C.

2016-01-01

Many experiments have found that participants take more investment risk if they see returns less frequently, see portfolio-level returns (rather than each individual asset’s returns), or see long-horizon (rather than one-year) historical return distributions. In contrast, we find that such information aggregation treatments do not affect total equity investment when we make the investment environment more realistic than in prior experiments. Previously documented aggregation effects are not robust to changes in the risky asset’s return distribution or the introduction of a multi-day delay between portfolio choice and return realizations. PMID:28553012

Judging Risk and Return of Financial Assets.

PubMed

Ganzach

2000-11-01

This article examines the relationship between judgments of risk and judgments of expected return of financial assets. It suggests that for unfamiliar assets, both risk and return judgments are derived from global preference toward the asset, whereas for familiar assets, these judgments tend to be derived from the ecological values of the asset's risk and expected return-their values in the financial markets. In addition, the article examines the role of causal schemas and the role of risk attitudes in mediating the relationships between judgments of risk and return of familiar and unfamiliar assets. Conceptual and practical questions concerning the nature, the meaning, and the assessment of risk and expected return are discussed. Copyright 2000 Academic Press.

On-field management and return-to-play in sports-related concussion in children: Are children managed appropriately?

PubMed

Haran, Harini P; Bressan, Silvia; Oakley, Ed; Davis, Gavin A; Anderson, Vicki; Babl, Franz E

2016-03-01

On-field management and return-to-play guidelines aim to ensure the identification and appropriate management of the concussed athlete. Compliance with current guidelines in many settings is unknown. We assessed whether key components of current concussion guidelines are being followed in child athletes. Prospective observational study. Data were collected from children (5-18 years) presenting to a paediatric emergency department with sport-related concussion via researcher-administered surveys in the emergency department and during a follow up phone call. On hospital discharge all patients received a return to sports fact sheet based on the International Concussion in Sports Group. Ninety-three had sustained a concussion (mean age 12.7 (±0.27) years, 83% male). Sports played included Australian Football (47%), soccer (12%), rugby (9%) basketball (8%), other (25%). 82% participated in organised sports. Concussive signs or symptoms included loss of consciousness (41%), disorientation (36%), vomiting (23%), amnesia (30%), headache (60%). For concussive injury in organised sports (n=76), overall 42% were not managed according to recommended guidelines: 19% were not immediately removed from play, 29% were allowed to return to play on the same day and 27% were not assessed by qualified personnel. 93% of parents and 96% of patients were unaware of concussion or return-to-play guidelines from their organisations. Overall, 72% were compliant with provided return-to-play guidelines. Many children with sports related-concussion are not formally assessed on-field and continue to play. On-field concussion management and return to play practices are often suboptimal. Awareness and education of coaches, teachers, parents and children need to be improved. Copyright © 2015 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Gating current studies reveal both intra- and extracellular cation modulation of K+ channel deactivation

PubMed Central

Wang, Zhuren; Zhang, Xue; Fedida, David

1999-01-01

The presence of permeant ions can modulate the rate of gating charge return in wild-type human heart K+ (hKv1.5) channels. Here we employ gating current measurements in a non-conducting mutant, W472F, of the hKv1.5 channel to investigate how different cations can modulate charge return and whether the actions can be specifically localized at the internal as well as the external mouth of the channel pore. Intracellular cations were effective at accelerating charge return in the sequence Cs+ > Rb+ > K+ > Na+ > NMG+. Extracellular cations accelerated charge return with the selectivity sequence Cs+ > Rb+ > Na+ = NMG+. Intracellular and extracellular cation actions were of relatively low affinity. The Kd for preventing slowing of the time constant of the off-gating current decay (τoff) was 20.2 mM for intracellular Cs+ (Csi+) and 358 mM for extracellular Cs+ (Cso+). Both intracellular and extracellular cations can regulate the rate of charge return during deactivation of hKv1.5, but intracellular cations are more effective. We suggest that ion crystal radius is an important determinant of this action, with larger ions preventing slowing more effectively. Important parallels exist with cation-dependent modulation of slow inactivation of ionic currents in this channel. However, further experiments are required to understand the exact relationship between acceleration of charge return and the slowing of inactivation of ionic currents by cations. PMID:10050001

Estimates of Lagrangian particle transport by wave groups: forward transport by Stokes drift and backward transport by the return flow

NASA Astrophysics Data System (ADS)

van den Bremer, Ton S.; Taylor, Paul H.

2014-11-01

Although the literature has examined Stokes drift, the net Lagrangian transport by particles due to of surface gravity waves, in great detail, the motion of fluid particles transported by surface gravity wave groups has received considerably less attention. In practice nevertheless, the wave field on the open sea often has a group-like structure. The motion of particles is different, as particles at sufficient depth are transported backwards by the Eulerian return current that was first described by Longuet-Higgins & Stewart (1962) and forms an inseparable counterpart of Stokes drift for wave groups ensuring the (irrotational) mass balance holds. We use WKB theory to study the variation of the Lagrangian transport by the return current with depth distinguishing two-dimensional seas, three-dimensional seas, infinite depth and finite depth. We then provide dimensional estimates of the net horizontal Lagrangian transport by the Stokes drift on the one hand and the return flow on the other hand for realistic sea states in all four cases. Finally we propose a simple scaling relationship for the transition depth: the depth above which Lagrangian particles are transported forwards by the Stokes drift and below which such particles are transported backwards by the return current.

Going home after Hurricane Katrina: Determinants of return migration and changes in affected areas.

PubMed

Groen, Jeffrey A; Polivka, Anne E

2010-11-01

This article examines the decision of Hurricane Katrina evacuees to return to their pre-Katrina areas and documents how the composition of the Katrina-affected region changed over time. Using data from the Current Population Survey, we show that an evacuee's age, family income, and the severity of damage in an evacuee's county of origin are important determinants of whether an evacuee returned during the first year after the storm. Blacks were less likely to return than whites, but this difference is primarily related to the geographical pattern of storm damage rather than to race per se. The difference between the composition of evacuees who returned and the composition of evacuees who did not return is the primary force behind changes in the composition of the affected areas in the first two years after the storm. Katrina is associated with substantial shifts in the racial composition of the affected areas (namely, a decrease in the percentage of residents who are black) and an increasing presence of Hispanics. Katrina is also associated with an increase in the percentage of older residents, a decrease in the percentage of residents with low income/education, and an increase in the percentage of residents with high income/education.

49 CFR 236.720 - Circuit, common return.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Circuit, common return. 236.720 Section 236.720 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Circuit, common return. A term applied where one wire is used for the return of more than one electric...

78 FR 16519 - Agency Information Collection Activities: Application for Advance Permission To Return to...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-15

...-0016] Agency Information Collection Activities: Application for Advance Permission To Return to... Currently Approved Collection. (2) Title of the Form/Collection: Application for Advance Permission to..., 10 minutes for reading the instructions, and 35 minutes for completing and submitting the application...

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

... DEPARTMENT OF THE TREASURY Internal Revenue Service 26 CFR Part 301 [REG-153338-09] RIN 1545-BJ19 Disclosure of Returns and Return Information to Designee of Taxpayer; Hearing Cancellation AGENCY: Internal... was scheduled for June 9, 2011, at 10 a.m. in the IRS Auditorium, Internal Revenue Building, 1111...

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

Planetary Protection Requirements for Mars Sample Return Missions: Recommendations from a 2009 NRC Report

NASA Astrophysics Data System (ADS)

Race, Margaret; Farmer, Jack

A 2009 report by the National Research Council (NRC) reviewed a previous study on Mars Sample Return (1997) and provided updated recommendations for future sample return mis-sions based on our current understanding about Mars and its biological potential, as well as advances in technology and analytical capabilities. The committee* made 12 specific recommen-dations that fall into three general categories—one related to current scientific understanding, ten based on changes in the technical and/or policy environment, and one aimed at public com-munication. Substantive changes from the 1997 report relate mainly to protocols and methods, technology and infrastructure, and general oversight. This presentation provides an overview of the 2009 report and its recommendations and analyzes how they may impact mission designs and plans. The full report, Assessment of Planetary Protection Requirements for Mars Sample Return Missions is available online at: http://www.nap.edu/catalog.php?recordi d = 12576 * Study participants: Jack D. Farmer, Arizona State University (chair) James F. Bell III, Cornell University Kathleen C. Benison, Central Michigan University William V. Boynton, University of Arizona Sherry L. Cady, Portland State University F. Grant Ferris, University of Toronto Duncan MacPherson, Jet Propulsion Laboratory Margaret S. Race, SETI Institute Mark H. Thiemens, University of California, San Diego Meenakshi Wadhwa, Arizona State University

Bereaved Employee: Returning to Work

MedlinePlus

... Out-of-town relatives return home. Children go back to school and grieving adults must get back to work. For some, returning to work is ... one is a long, slow process, but getting back into a routine is an important step in the journey. Share this: ... Copyright Information The materials on this website are ...

Mars double-aeroflyby free returns

NASA Astrophysics Data System (ADS)

Jesick, Mark

2017-09-01

Mars double-flyby free-return trajectories that pass twice through the Martian atmosphere are documented. This class of trajectories is advantageous for potential Mars atmospheric sample return missions because of its low geocentric energy at departure and arrival, because it would enable two sample collections at unique locations during different Martian seasons, and because of its lack of deterministic maneuvers. Free return opportunities are documented over Earth departure dates ranging from 2015 through 2100, with viable missions available every Earth-Mars synodic period. After constraining the maximum lift-to-drag ratio to be less than one, the minimum observed Earth departure hyperbolic excess speed is 3.23 km/s, the minimum Earth atmospheric entry speed is 11.42 km/s, and the minimum round-trip flight time is 805 days. An algorithm using simplified dynamics is developed along with a method to derive an initial estimate for trajectories in a more realistic dynamic model. Multiple examples are presented, including free returns that pass outside and inside of Mars's appreciable atmosphere.

The Importance of Meteorite Collections to Sample Return Missions: Past, Present, and Future Considerations

NASA Technical Reports Server (NTRS)

Welzenbach, L. C.; McCoy, T. J.; Glavin, D. P.; Dworkin, J. P.; Abell, P. A.

2012-01-01

While much of the scientific community s current attention is drawn to sample return missions, it is the existing meteorite and cosmic dust collections that both provide the paradigms to be tested by these missions and the context for interpreting the results. Recent sample returns from the Stardust and Hayabusa missions provided us with new materials and insights about our Solar System history and processes. As an example, Stardust sampled CAIs among the population of cometary grains, requiring extensive and unexpected radial mixing in the early solar nebula. This finding would not have been possible, however, without extensive studies of meteoritic CAIs that established their high-temperature, inner Solar System formation. Samples returned by Stardust also revealed the first evidence of a cometary amino acid, a discovery that would not have been possible with current in situ flight instrument technology. The Hayabusa mission provided the final evidence linking ordinary chondrites and S asteroids, a hypothesis that developed from centuries of collection and laboratory and ground-based telescopic studies. In addition to these scientific findings, studies of existing meteorite collections have defined and refined the analytical techniques essential to studying returned samples. As an example, the fortuitous fall of the Allende CV3 and Murchison CM2 chondrites within months before the return of Apollo samples allowed testing of new state-of-the-art analytical facilities. The results of those studies not only prepared us to better study lunar materials, but unanticipated discoveries changed many of our concepts about the earliest history and processes of the solar nebula. This synergy between existing collections and future space exploration is certainly not limited to sample return missions. Laboratory studies confirmed the existence of meteorites from Mars and raised the provocative possibility of preservation of ancient microbial life. The laboratory studies in

Influences on the Intention to Enter Higher Education: The Importance of Expected Returns

ERIC Educational Resources Information Center

Menon, Maria Eliophotou; Markadjis, Elias; Theodoropoulos, Nikolaos; Socratous, Michalis

2017-01-01

Research points to several determinants of the private demand for higher education, which include individual, social, economic, and institutional variables. Of these variables, economic factors are considered to be highly relevant, especially in the current financial crisis. The paper investigates the link between expected rates of return to…

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…

Sample Return Robot Centennial Challenge

NASA Image and Video Library

2012-06-16

A judge for the NASA-WPI Sample Return Robot Centennial Challenge follows a robot on the playing field during the challenge on Saturday, June 16, 2012 in Worcester, Mass. Teams were challenged to build autonomous robots that can identify, collect and return samples. NASA needs autonomous robotic capability for future planetary exploration. Photo Credit: (NASA/Bill Ingalls)

22 CFR 42.22 - Returning resident aliens.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Returning resident aliens. 42.22 Section 42.22... Returning resident aliens. (a) Requirements for returning resident status. An alien shall be classifiable as... presented that: (1) The alien had the status of an alien lawfully admitted for permanent residence at the...

22 CFR 42.22 - Returning resident aliens.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 22 Foreign Relations 1 2012-04-01 2012-04-01 false Returning resident aliens. 42.22 Section 42.22... Returning resident aliens. (a) Requirements for returning resident status. An alien shall be classifiable as... presented that: (1) The alien had the status of an alien lawfully admitted for permanent residence at the...

22 CFR 42.22 - Returning resident aliens.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Returning resident aliens. 42.22 Section 42.22... Returning resident aliens. (a) Requirements for returning resident status. An alien shall be classifiable as... presented that: (1) The alien had the status of an alien lawfully admitted for permanent residence at the...

22 CFR 42.22 - Returning resident aliens.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Returning resident aliens. 42.22 Section 42.22... Returning resident aliens. (a) Requirements for returning resident status. An alien shall be classifiable as... presented that: (1) The alien had the status of an alien lawfully admitted for permanent residence at the...

22 CFR 42.22 - Returning resident aliens.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Returning resident aliens. 42.22 Section 42.22... Returning resident aliens. (a) Requirements for returning resident status. An alien shall be classifiable as... presented that: (1) The alien had the status of an alien lawfully admitted for permanent residence at the...

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.

Physicians' assessment of pediatric returns to the Emergency Department.

PubMed

Easter, Joshua S; Bachur, Richard

2013-03-01

Return visits to the Emergency Department (ED) requiring admission are frequently reviewed for the purpose of quality improvement. Treating physicians typically perform this review, but it is unclear if they accurately identify the reasons for the returns. To assess the characteristics of pediatric return visits to the ED, and the ability of treating physicians to identify the root causes for these return visits. This retrospective cohort study reviewed all returns within 96 h of an initial visit over a 2-year period at a tertiary care pediatric ED. Baseline characteristics were determined from review of patients' charts. The treating physicians, the primary author, and independent reviewers identified the root cause for the returns. There were 97,374 patients that presented to the ED during the study, and 1091 (1.1%) of these children returned to the ED and were admitted. Returns were most common among children aged<5 years, arriving between 3:00 p.m. and 11:00 p .m. via private transportation, with infectious diseases. The physician involved in the care of the patient attributed 3.1% of returns to potential deficiencies in medical management, whereas the independent reviewers attributed 13% to potential deficiencies. Both returns and the subset of returns due to potential deficiencies in management are more common than previously estimated, rendering review of returns a valuable quality improvement tool. However, EDs should not rely exclusively on the treating physicians to identify the reason for returns, as they seem to underestimate the frequency of returns due to potential deficiencies in medical management. Copyright © 2013 Elsevier Inc. All rights reserved.

Vacuum-assisted venous return reduces blood usage.

PubMed

Banbury, Michael K; White, Jennifer A; Blackstone, Eugene H; Cosgrove, Delos M

2003-09-01

To determine whether vacuum-assisted venous return has clinical advantages over conventional gravity drainage apart from allowing the use of smaller cannulas and shorter tubing. A total of 150 valve operations were performed at our institution between February and July 1999 using vacuum-assisted venous return with small venous cannulas connected to short tubing. These were compared with (1) 83 valve operations performed between April 1997 and January 1998 using the initial version of vacuum-assisted venous return, and (2) 124 valve operations performed between January and April of 1997 using conventional gravity drainage. Priming volume, hematocrit value, red blood cell usage, and total blood product usage were compared multivariably. These comparisons were covariate and propensity adjusted for dissimilarities between the groups and confirmed by propensity-matched pairs analysis. Priming volume was 1.4 +/- 0.4 L for small-cannula vacuum-assisted venous return, 1.7 +/- 0.4 L for initial vacuum-assisted venous return, and 2.0 +/- 0.4 L for gravity drainage (P <.0001). Smaller priming resulted in higher hematocrit values both at the beginning of cardiopulmonary bypass (27% +/- 5% compared with 26% +/- 4% and 25% +/- 4%, respectively, P <.0001) and at the end (30% +/- 4% compared with 28% +/- 4% and 27% +/- 4%, respectively, P <.0001). Red cell transfusions were used in 17% of the patients having small-cannula vacuum-assisted venous return, 27% of the initial patients having vacuum-assisted venous return, and 37% of the patients having gravity drainage (P =.001); total blood product usage was 19%, 27%, and 39%, respectively (P =.002). Although ministernotomy also was associated with reduced blood product usage (P <.004), propensity matching on type of sternotomy confirmed the association of vacuum-assisted venous return with lowered blood product usage. Vacuum-assisted venous return results in (1) higher hematocrit values during cardiopulmonary bypass and (2) decreased

Mars Rover Sample Return mission study

NASA Technical Reports Server (NTRS)

Bourke, Roger D.

1989-01-01

The Mars Rover/Sample Return mission is examined as a precursor to a manned mission to Mars. The value of precursor missions is noted, using the Apollo lunar program as an example. The scientific objectives of the Mars Rover/Sample Return mission are listed and the basic mission plans are described. Consideration is given to the options for mission design, launch configurations, rover construction, and entry and lander design. Also, the potential for international cooperation on the Mars Rover/Sample Return mission is discussed.

Application of Solar Electric Propulsion to a Comet Surface Sample Return Mission

NASA Technical Reports Server (NTRS)

Cupples, Mike; Coverstone, Victoria; Woo, Byoungsam

2004-01-01

Current NSTAR (planned for the Discovery Mission: Dawn) and NASA's Evolutionary Xenon Thruster based propulsion systems were compared for a comet surface sample return mission to Tempe1 1. Mission and systems analyses were conducted over a range of array power for each propulsion system with an array of 12 kW EOL at 1 AU chosen for a baseline. Engine configurations investigated for NSTAR included 4 operational engines with 1 spare and 5 operational engines with 1 spare. The NEXT configuration investigated included 2 operational engines plus 1 spare, with performance estimated for high thrust and high Isp throttling modes. Figures of merit for this comparison include Solar Electric Propulsion dry mass, average engine throughput, and net non-propulsion payload returned to Earth flyby.

INDOT Research Program Benefit Cost Analysis—Return on Investment for Projects Completed in FY 2016

DOT National Transportation Integrated Search

2017-12-01

The Governors Office requested an annual financial analysis of the INDOT Research Program to determine the return on the research investment (ROI). The current financial analysis is for research projects that completed in FY 2016. Analyses on prev...

Mars Sample Return without Landing on the Surface

NASA Technical Reports Server (NTRS)

Jurewicz, A. J. G.; Jones, Steven M.; Yen, A. S.

2000-01-01

Many in the science community want a Mars sample return in the near future, with the expectation that it will provide in-depth information, significantly beyond what we know from remote sensing, limited in-situ measurements, and work with Martian meteorites. Certainly, return of samples from the Moon resulted in major advances in our understanding of both the geologic history of our planetary satellite, and its relationship to Earth. Similar scientific insights would be expected from analyses of samples returned from Mars. Unfortunately, Mars-lander sample-return missions have been delayed, for the reason that NASA needs more time to review the complexities and risks associated with that type of mission. A traditional sample return entails a complex transfer-chain, including landing, collection, launch, rendezvous, and the return to Earth, as well as an evaluation of potential biological hazards involved with bringing pristine Martian organics to Earth. There are, however, means of returning scientifically-rich samples from Mars without landing on the surface. This paper discusses an approach for returning intact samples of surface dust, based on known instrument technology, without using an actual Martian lander.

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.

75 FR 76940 - Specified Tax Return Preparers Required To File Individual Income Tax Returns Using Magnetic...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-10

... DEPARTMENT OF THE TREASURY Internal Revenue Service 26 CFR Parts 1 and 301 [REG-100194-10] RIN 1545-BJ52 Specified Tax Return Preparers Required To File Individual Income Tax Returns Using Magnetic Media; Correction AGENCY: Internal Revenue Service (IRS), Treasury. ACTION: Correction to notice of...

Return Intervals Approach to Financial Fluctuations

NASA Astrophysics Data System (ADS)

Wang, Fengzhong; Yamasaki, Kazuko; Havlin, Shlomo; Stanley, H. Eugene

Financial fluctuations play a key role for financial markets studies. A new approach focusing on properties of return intervals can help to get better understanding of the fluctuations. A return interval is defined as the time between two successive volatilities above a given threshold. We review recent studies and analyze the 1000 most traded stocks in the US stock markets. We find that the distribution of the return intervals has a well approximated scaling over a wide range of thresholds. The scaling is also valid for various time windows from one minute up to one trading day. Moreover, these results are universal for stocks of different countries, commodities, interest rates as well as currencies. Further analysis shows some systematic deviations from a scaling law, which are due to the nonlinear correlations in the volatility sequence. We also examine the memory in return intervals for different time scales, which are related to the long-term correlations in the volatility. Furthermore, we test two popular models, FIGARCH and fractional Brownian motion (fBm). Both models can catch the memory effect but only fBm shows a good scaling in the return interval distribution.

Return of Individual Research Results and Incidental Findings in the Clinical Trials Cooperative Group Setting

PubMed Central

Ferriere, Michael; Van Ness, Brian

2013-01-01

The NCI funded cooperative group cancer clinical trial system develops experimental therapies and often collects patient samples for correlative research. The Cooperative Group Bank (CGB) system maintains biobanks with a current policy not to return research results to individuals. An online survey was created, and 10 directors of CGBs completed the surveys asking about understanding and attitudes in changing policies to consider return of Incidental Findings (IFs) and Individual Research Results (IRRs) of health significance. The potential impact of the ten consensus recommendations of Wolf et al. presented in this issue are examined. Re-identification of samples is often not problematic; however, changes to the current banking and clinical trial systems would require significant effort to fulfill an obligation of recontact of subjects. Additional resources, as well as a national advisory board would be required to standardize implementation. PMID:22382800

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.

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.

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.

Application of the Lienard-Wiechert solution to a lightning return stroke model

NASA Technical Reports Server (NTRS)

Meneghini, R.

1983-01-01

The electric and magnetic fields associated with the lightning return stroke are expressed as a convolution of the current waveform shape and the fields generated by a moving charge of amplitude one (i.e., the Lienard-Wiechert solution for a unit charge). The representation can be used to compute the fields produced by a current waveform of non-uniform velocity that propagates along a filament of arbitrary, but finite, curvature. To study numerically the effects of linear charge acceleration and channel curvature two simple channel models are used: the linear and the hyperbolic.

Application of the Lienard-Wiechert solution to a lightning return stroke model

NASA Technical Reports Server (NTRS)

Meneghini, R.

1984-01-01

The electric and magnetic fields associated with the lightning return stroke are expressed as a convolution of the current waveform shape and the fields generated by a moving charge of amplitude one (i.e., the Lienard-Wiechert solution for a unit charge). The representation can be used to compute the fields produced by a current waveform of non-uniform velocity that propagates along a filament of arbitrary, but finite, curvature. To study numerically the effects of linear charge acceleration and channel curvature two simple channel models are used: the linear and the hyperbolic.

2016 Consensus statement on return to sport from the First World Congress in Sports Physical Therapy, Bern.

PubMed

Ardern, Clare L; Glasgow, Philip; Schneiders, Anthony; Witvrouw, Erik; Clarsen, Benjamin; Cools, Ann; Gojanovic, Boris; Griffin, Steffan; Khan, Karim M; Moksnes, Håvard; Mutch, Stephen A; Phillips, Nicola; Reurink, Gustaaf; Sadler, Robin; Silbernagel, Karin Grävare; Thorborg, Kristian; Wangensteen, Arnlaug; Wilk, Kevin E; Bizzini, Mario

2016-07-01

Deciding when to return to sport after injury is complex and multifactorial-an exercise in risk management. Return to sport decisions are made every day by clinicians, athletes and coaches, ideally in a collaborative way. The purpose of this consensus statement was to present and synthesise current evidence to make recommendations for return to sport decision-making, clinical practice and future research directions related to returning athletes to sport. A half day meeting was held in Bern, Switzerland, after the First World Congress in Sports Physical Therapy. 17 expert clinicians participated. 4 main sections were initially agreed upon, then participants elected to join 1 of the 4 groups-each group focused on 1 section of the consensus statement. Participants in each group discussed and summarised the key issues for their section before the 17-member group met again for discussion to reach consensus on the content of the 4 sections. Return to sport is not a decision taken in isolation at the end of the recovery and rehabilitation process. Instead, return to sport should be viewed as a continuum, paralleled with recovery and rehabilitation. Biopsychosocial models may help the clinician make sense of individual factors that may influence the athlete's return to sport, and the Strategic Assessment of Risk and Risk Tolerance framework may help decision-makers synthesise information to make an optimal return to sport decision. Research evidence to support return to sport decisions in clinical practice is scarce. Future research should focus on a standardised approach to defining, measuring and reporting return to sport outcomes, and identifying valuable prognostic factors for returning to sport. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Declining Returns.

ERIC Educational Resources Information Center

Rosen, Gerald H.; Perrin, Robert

1992-01-01

The Teachers Insurance and Annuities Association's (TIAA) College Retirement and Equity Fund is criticized for its low returns and its chief executive officer's recent salary raise. It is said to be in need of additional regulation and policyholder involvement. A TIAA vice president responds that the analysis given is inaccurate and misleading.…

Stardust Returns to Earth Artist Concept

NASA Image and Video Library

2005-11-03

Artist rendering of NASA’s Stardust returning to Earth. Stardust is the first U.S. space mission dedicated to the exploration of a comet, and the first robotic mission designed to return extraterrestrial material from outside the orbit of the Moon.

Characterization of the Ionosphere over the South Atlantic Ocean by Means of Ionospheric Tomography using Dual Frequency GPS Signals Received On Board a Research Ship

DTIC Science & Technology

2006-06-01

space environment. 1.0 INTRODUCTION The current geographical coverage of the International GNSS Service (IGS) tracking network limits the spatial...routes to Antarctica and the Southern Ocean Islands serviced by the South African National Antarctic programme (SANAP). The routes of the SA Agulhas to...collection of information, including suggestions for reducing this burden, to Washington Headquarters Services , Directorate for Information

Influence of sleep on symptom improvement and return to work in clinical burnout.

PubMed

Sonnenschein, Mieke; Sorbi, Marjolijn J; Verbraak, Marc J P M; Schaufeli, Wilmar B; Maas, Cora J M; van Doornen, Lorenz J P

2008-02-01

The current study examined the extent to which symptom improvement and full return to work occurs among clinically burnt-out employees and what the influence of concurring sleep problems is with respect to health recovery. Fifty-nine burnt-out employees on extended sick leave assessed their symptoms for 2 weeks using an electronic diary. After 6 months, the measurements were repeated. Symptom levels were compared with those of a healthy reference group that was assessed only once. After 6 months, all burnout symptoms had decreased significantly, and full return to work was achieved by 37% of the burnt-out individuals. The symptom levels at 6 months of follow-up among those who had fully returned to work were similar to healthy levels and significantly lower than the levels of those still on sick leave. The persons who benefited poorly from sleep at baseline had higher exhaustion levels at follow-up than those who benefited from sleep. Trouble falling asleep and less refreshing sleep at baseline hampered eventual full work resumption. The results show that a significant number of clinically burnt-out employees is able to recover in a 6-month period and that sleep plays an important role both in symptom improvement and in return to work.

Model for non-Gaussian intraday stock returns

NASA Astrophysics Data System (ADS)

Gerig, Austin; Vicente, Javier; Fuentes, Miguel A.

2009-12-01

Stock prices are known to exhibit non-Gaussian dynamics, and there is much interest in understanding the origin of this behavior. Here, we present a model that explains the shape and scaling of the distribution of intraday stock price fluctuations (called intraday returns) and verify the model using a large database for several stocks traded on the London Stock Exchange. We provide evidence that the return distribution for these stocks is non-Gaussian and similar in shape and that the distribution appears stable over intraday time scales. We explain these results by assuming the volatility of returns is constant intraday but varies over longer periods such that its inverse square follows a gamma distribution. This produces returns that are Student distributed for intraday time scales. The predicted results show excellent agreement with the data for all stocks in our study and over all regions of the return distribution.

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.

]. Current Plan: At the 1st flyby of Enceladus at high plume altitude (~150 km), we would survey the status of the plume and jets by making in situ measurements of the gas and dust densities, compositions, and velocities. We would also collect solid ice/volatile samples based upon prior ground planning. The 2nd and final flyby (determined via optimal trajectory from the 1st flyby) will be conducted at low altitude (~20 km), and would perform in situ measurements and collect solid ice and volatile samples. During the 5 year return cruise, we would maintain the samples in their captured state (frozen) under desiccating conditions of low temperature and pressure. After a direct Earth reentry, we would transport the frozen samples from the sample return capsule into a sealed sample transport container, which would then be transported to a higher Biosafety Level (BSL) facility from JAMSTEC (Japan Agency for Marine-Earth Science and Technology) for sample return capsule de-integration and sample distribution. Planetary Protection: Several options for sample return have been conceived and some even demonstrated on previous flight missions (STARDUST, Genesis and Hayabusa). To date, a flight qualified sample containment system does not exist in the US, and it would be cost prohibitive to flight-qualify such a system for use by LIFE under a Discovery Program. Harsh sterilization of the samples would destroy valuable molecular information, defeating the very purpose of returning samples to assess the habitability of Enceladus. The LIFE team has found a viable approach by teaming with JAXA/ISAS. Their Hayabusa II sample containment is a third generation device that can be further improved to meet these NASA and COSPAR planetary protection requirements in an Integrated Sample Subsystem for LIFE. Another aspect of LIFE is the initial de-integration and certification of the returned samples in a higher BSL facility. JAMSTEC is the world’s leading oceanography organization. They are

Building uncertainty into cost-effectiveness rankings: portfolio risk-return tradeoffs and implications for decision rules.

PubMed

O'Brien, B J; Sculpher, M J

2000-05-01

Current principles of cost-effectiveness analysis emphasize the rank ordering of programs by expected economic return (eg, quality-adjusted life-years gained per dollar expended). This criterion ignores the variance associated with the cost-effectiveness of a program, yet variance is a common measure of risk when financial investment options are appraised. Variation in health care program return is likely to be a criterion of program selection for health care managers with fixed budgets and outcome performance targets. Characterizing health care resource allocation as a risky investment problem, we show how concepts of portfolio analysis from financial economics can be adopted as a conceptual framework for presenting cost-effectiveness data from multiple programs as mean-variance data. Two specific propositions emerge: (1) the current convention of ranking programs by expected return is a special case of the portfolio selection problem in which the decision maker is assumed to be indifferent to risk, and (2) for risk-averse decision makers, the degree of joint risk or covariation in cost-effectiveness between programs will create incentives to diversify an investment portfolio. The conventional normative assumption of risk neutrality for social-level public investment decisions does not apply to a large number of health care resource allocation decisions in which health care managers seek to maximize returns subject to budget constraints and performance targets. Portfolio theory offers a useful framework for studying mean-variance tradeoffs in cost-effectiveness and offers some positive predictions (and explanations) of actual decision making in the health care sector.

Evaluation of the return rate of volunteer blood donors

PubMed Central

Lourençon, Adriana de Fátima; Almeida, Rodrigo Guimarães dos Santos; Ferreira, Oranice; Martinez, Edson Zangiacomi

2011-01-01

Background To convert first-time blood donors into regular volunteer donors is a challenge to transfusion services. Objectives This study aims to estimate the return rate of first time donors of the Ribeirão Preto Blood Center and of other blood centers in its coverage region. Methods The histories of 115,553 volunteer donors between 1996 and 2005 were analyzed. Statistical analysis was based on a parametric long-term survival model that allows an estimation of the proportion of donors who never return for further donations. Results Only 40% of individuals return within one year after the first donation and 53% return within two years. It is estimated that 30% never return to donate. Higher return rates were observed among Black donors. No significant difference was found in non-return rates regarding gender, blood type, Rh blood group and blood collection unit. Conclusions The low percentage of first-time donors who return for further blood donation reinforces the need for marketing actions and strategies aimed at increasing the return rates. PMID:23049294

Venus Surface Sample Return: A Weighty High-Pressure Challenge

NASA Technical Reports Server (NTRS)

Sweetser, Ted; Cameron, Jonathon; Chen, Gun-Shing; Cutts, Jim; Gershman, Bob; Gilmore, Martha S.; Hall, Jeffrey L.; Kerzhanovich, Viktor; McRonald, Angus; Nilsen, Erik

1999-01-01

A mission to return a sample to Earth from the surface of Venus faces a multitude of multidisciplinary challenges. In addition to the complications inherent in any sample return mission, Venus presents the additional difficulties of a deep gravity well essentially equivalent to Earth's and a hot-house atmosphere which generates extremes of high temperature, density, and pressure unmatched at any other known surface in the solar system. The Jet Propulsion Laboratory of the California Institute of Technology recently conducted a study to develop an architecture for such a mission; a major goal of this study was to identify technology developments which would need to be pursued in order to make such a mission feasible at a cost much less than estimated in previous. The final design of this mission is years away but the study results presented here show our current mission architecture as it applies to a particular mission opportunity, give a summary of the engineering and science trades which were made in the process of developing it, and identify the main technology development efforts needed.

MSR ESA Earth Return Orbiter Mission Design Trades

NASA Astrophysics Data System (ADS)

Sanchez Perez, J. M.; Varga, G. I.; Huesing, J.; Beyer, F.

2018-04-01

The paper describes the work performed at ESOC in support of the Mars Sample Return ESA Earth Return Orbiter definition studies by exploring the trajectory optimization and mission design trade spaces of Mars return missions using electric and chemical propulsion.

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. c2001 COSPAR Published by Elsevier Science Ltd. All rights reserved.

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.

Mars Rover Sample Return mission

NASA Technical Reports Server (NTRS)

Bourke, Roger D.; Kwok, Johnny H.; Friedlander, Alan

1989-01-01

To gain a detailed understanding of the character of the planet Mars, it is necessary to send vehicle to the surface and return selected samples for intensive study in earth laboratories. Toward that end, studies have been underway for several years to determine the technically feasible means for exploring the surface and returning selected samples. This paper describes several MRSR mission concepts that have emerged from the most recent studies.

Heterogeneous belief and asset returns

NASA Astrophysics Data System (ADS)

Lei-Sun, Wen-Zou, Hui

2014-10-01

Based on DSSW model, this paper introduces the noise traders with heterogeneous belief. With an equilibrium analysis, this paper examines the return of risky asset. The results show that the belief biases, the probability of economy state, the degree of the heterogeneous noise trader's aversion risk, the coefficient between heterogeneous noise traders are all the factors that have effects on the risky asset pricing and the return of risky asset.

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.

An experimental test of the 'transmission-line model' of electromagnetic radiation from triggered lightning return strokes

NASA Technical Reports Server (NTRS)

Willett, J. C.; Idone, V. P.; Orville, R. E.; Leteinturier, C.; Eybert-Berard, A.

1988-01-01

Peak currents, two-dimensional average propagation speeds, and electric field waveforms for a number of subsequent return strikes in rocket-triggered lightning flashes were measured in order to test the 'transmission-line model' of return-stroke radiation of Uman and McLain (1970). Reasonable agreement is found between the propagation speeds measured with the streak camera and those deduced from the transmission-line model. A modification of the model is proposed in which two wave fronts travel upward and downward away from a junction point a short distance above the ground.

An experimental test of the 'transmission-line model' of electromagnetic radiation from triggered lightning return strokes

NASA Astrophysics Data System (ADS)

Willett, J. C.; Idone, V. P.; Orville, R. E.; Leteinturier, C.; Eybert-Berard, A.

1988-04-01

Peak currents, two-dimensional average propagation speeds, and electric field waveforms for a number of subsequent return strikes in rocket-triggered lightning flashes were measured in order to test the 'transmission-line model' of return-stroke radiation of Uman and McLain (1970). Reasonable agreement is found between the propagation speeds measured with the streak camera and those deduced from the transmission-line model. A modification of the model is proposed in which two wave fronts travel upward and downward away from a junction point a short distance above the ground.

Jump-and-return sandwiches: A new family of binomial-like selective inversion sequences with improved performance

NASA Astrophysics Data System (ADS)

Brenner, Tom; Chen, Johnny; Stait-Gardner, Tim; Zheng, Gang; Matsukawa, Shingo; Price, William S.

2018-03-01

A new family of binomial-like inversion sequences, named jump-and-return sandwiches (JRS), has been developed by inserting a binomial-like sequence into a standard jump-and-return sequence, discovered through use of a stochastic Genetic Algorithm optimisation. Compared to currently used binomial-like inversion sequences (e.g., 3-9-19 and W5), the new sequences afford wider inversion bands and narrower non-inversion bands with an equal number of pulses. As an example, two jump-and-return sandwich 10-pulse sequences achieved 95% inversion at offsets corresponding to 9.4% and 10.3% of the non-inversion band spacing, compared to 14.7% for the binomial-like W5 inversion sequence, i.e., they afforded non-inversion bands about two thirds the width of the W5 non-inversion band.

Communication and collaboration among return-to-work stakeholders.

PubMed

Russell, Elizabeth; Kosny, Agnieszka

2018-05-17

Workers who are injured or become ill on the job are best able to return-to-work when stakeholders involved in their case collaborate and communicate. This study examined health care providers' and case managers' engagement in rehabilitation and return-to-work following workplace injury or illness. In-depth interviews were conducted with 97 health care providers and 34 case managers in four Canadian provinces about their experiences facilitating rehabilitation and return-to-work, and interacting with system stakeholders. A qualitative thematic content analysis demonstrated two key findings. Firstly, stakeholders were challenged to collaborate as a result of: barriers to interdisciplinary and cross-professional communication; philosophical differences about the timing and appropriateness of return-to-work; and confusion among health care providers about the workers' compensation system. Secondly, these challenges adversely affected the co-ordination of patient care, and consequentially, injured workers often became information conduits, and effective and timely treatment and return-to-work was sometimes negatively impacted. Communication challenges between health care providers and case managers may negatively impact patient care and alienate treating health care providers. Discussion about role clarification, the appropriateness of early return-to-work, how paperwork shapes health care providers' role expectations, and strengthened inter-professional communication are considered. Implications for Rehabilitation Administrative and conceptual barriers in workers' compensation systems challenge collaboration and communication between health care providers and case managers. Injured workers may become conduits of incorrect information, resulting in adversarial relationships, overturned health care providers' recommendations, and their disengagement from rehabilitation and return-to-work. Stakeholders should clarify the role of health care providers during

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 of...

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 MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE War Risk Cargo Insurance Open Policy War Risk Cargo Insurance § 308.514 Return premium. No premium will be...

Healthier before they migrate, less healthy when they return? The health of returned migrants in Mexico

PubMed Central

Ullmann, S. Heidi; Goldman, Noreen; Massey, Douglas S.

2011-01-01

Over the course of the 20th century, Mexico-U.S. migration has emerged as an important facet of both countries, with far reaching economic and social impacts. The health of Mexican immigrants in the U.S. has been well studied, but relatively less is known about the health of returned migrants to Mexico. The objectives of this paper are twofold. Relying on health data pertaining to two stages of the life course, early life health (pre-migration) and adult health (post-migration) from the Mexican Migration Project gathered between 2007 and 2009, we aim to assess disparities in adult health status between male returned migrants and male non-migrants in Mexico, accounting for their potentially different early life health profiles. While we find evidence that returned migrants had more favorable early life health, the results for adult health are more complex. Returned migrants have a higher prevalence of heart disease, emotional/psychiatric disorders, obesity, and smoking than non-migrants but no differences are found in self-rated health, diabetes, or hypertension. PMID:21729820

Does graded return-to-work improve sick-listed workers' chance of returning to regular working hours?

PubMed

Høgelund, Jan; Holm, Anders; McIntosh, James

2010-01-01

Using Danish register and survey data, we examine the effect of a national graded return-to-work program on the probability of sick-listed workers returning to regular working hours. During program participation, the sick-listed worker works fewer hours and receives the normal hourly wage for the hours worked and sickness benefit for the hours off work. When the worker's health improves, working hours are increased until the sick-listed worker is able to work regular hours. Taking account of unobserved differences between program participants and non-participants, we find that participation in the program significantly increases the probability of returning to regular working hours. Copyright 2009 Elsevier B.V. All rights reserved.

Motivational goals, group identifications, and psychosocial adjustment of returning migrants: The case of Jews returning to Russia.

PubMed

Tartakovsky, Eugene; Patrakov, Eduard; Nikulina, Marina

2017-12-01

The present study investigated the motivational goals, group identifications, and psychosocial adjustment of Jews who returned to Russia after emigrating from the republics of the Former Soviet Union to different countries (n = 151). To gain a deeper understanding of these returning migrants, their traits were compared with those of Jews living in Russia who did not emigrate (n = 935). Compared to locals, returnees reported a higher preference for the openness to change and self-enhancement values and a lower preference for the conservation values; there was no difference in the self-transcendence values. Returning migrants had a relatively weak affiliation with the home country: they had a weaker identification with the home country than with the country of emigration, their identification with Russians was weaker than that among Jews who did not emigrate from Russia, and their intention to emigrate (again) from Russia was greater than that among locals. However, the Jewish identification of returning migrants was similar to that of locals. The adjustment of returning migrants varied across different dimensions: their economic adjustment was better than that of locals; however, the interpersonal adjustment of returnees was less successful than among locals. © 2016 International Union of Psychological Science.

Damage to metallic samples produced by measured lightning currents

NASA Technical Reports Server (NTRS)

Fisher, Richard J.; Schnetzer, George H.

1991-01-01

A total of 10 sample disks of 2024-T3 aluminum and 4130 ferrous steel were exposed to rocket-triggered lightning currents at the Kennedy Space Center test site. The experimental configuration was arranged so that the samples were not exposed to the preliminary streamer, wire-burn, or following currents that are associated with an upward-initiated rocket-triggered flash but which are atypical of naturally initiated lightning. Return-stroke currents and continuing currents actually attaching to the sample were measured, augmented by close-up video recordings of approximately 3 feet of the channel above the sample and by 16-mm movies with 5-ms resolution. From these data it was possible to correlate individual damage spots with streamer, return-stroke, and continuing currents that produced them. Substantial penetration of 80-mil aluminum was produced by a continuing current of submedian amplitude and duration, and full penetration of a 35-mil steel sample occurred under an eightieth percentile continuing current. The primary purpose of the data acquired in these experiments is for use in improving and quantifying the fidelity of laboratory simulations of lightning burnthrough.

46 CFR 308.514 - Return premium.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 8 2011-10-01 2011-10-01 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 be...

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 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...

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 be...

46 CFR 308.514 - Return premium.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 8 2012-10-01 2012-10-01 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 be...

EURO-CARES: European Roadmap for a Sample Return Curation Facility and Planetary Protection Implications.

NASA Astrophysics Data System (ADS)

Brucato, John Robert

2016-07-01

A mature European planetary exploration program and evolving sample return mission plans gathers the interest of a wider scientific community. The interest is generated from studying extraterrestrial samples in the laborato-ry providing new opportunities to address fundamental issues on the origin and evolution of the Solar System, on the primordial cosmochemistry, and on the nature of the building blocks of terrestrial planets and on the origin of life. Major space agencies are currently planning for missions that will collect samples from a variety of Solar Sys-tem environments, from primitive (carbonaceous) small bodies, from the Moon, Mars and its moons and, final-ly, from icy moons of the outer planets. A dedicated sample return curation facility is seen as an essential re-quirement for the receiving, assessment, characterization and secure preservation of the collected extraterrestrial samples and potentially their safe distribution to the scientific community. EURO-CARES is a European Commission study funded under the Horizon-2020 program. The strategic objec-tive of EURO-CARES is to create a roadmap for the implementation of a European Extraterrestrial Sample Cu-ration Facility. The facility has to provide safe storage and handling of extraterrestrial samples and has to enable the preliminary characterization in order to achieve the required effectiveness and collaborative outcomes for the whole international scientific community. For example, samples returned from Mars could pose a threat on the Earth's biosphere if any living extraterrestrial organism are present in the samples. Thus planetary protection is an essential aspect of all Mars sample return missions that will affect the retrival and transport from the point of return, sample handling, infrastructure methodology and management of a future curation facility. Analysis of the state of the art of Planetary Protection technology shows there are considerable possibilities to define and develop

Sample Return Robot Centennial Challenge

NASA Image and Video Library

2012-06-16

NASA Deputy Administrator Lori Garver, left, listens as Worcester Polytechnic Institute (WPI) Robotics Resource Center Director and NASA-WPI Sample Return Robot Centennial Challenge Judge Ken Stafford points out how the robots navigate the playing field during the challenge on Saturday, June 16, 2012 in Worcester, Mass. Teams were challenged to build autonomous robots that can identify, collect and return samples. NASA needs autonomous robotic capability for future planetary exploration. Photo Credit: (NASA/Bill Ingalls)

Sample Return Robot Centennial Challenge

NASA Image and Video Library

2012-06-16

NASA Deputy Administrator Lori Garver, right, listens as Worcester Polytechnic Institute (WPI) Robotics Resource Center Director and NASA-WPI Sample Return Robot Centennial Challenge Judge Ken Stafford points out how the robots navigate the playing field during the challenge on Saturday, June 16, 2012 in Worcester, Mass. Teams were challenged to build autonomous robots that can identify, collect and return samples. NASA needs autonomous robotic capability for future planetary exploration. Photo Credit: (NASA/Bill Ingalls)

Sample Return Robot Centennial Challenge

NASA Image and Video Library

2012-06-16

"Harry" a Goldendoodle is seen wearing a NASA backpack during the Worcester Polytechnic Institute (WPI) "TouchTomorrow" education and outreach event that was held in tandem with the NASA-WPI Sample Return Robot Centennial Challenge on Saturday, June 16, 2012 in Worcester, Mass. The challenge tasked robotic teams to build autonomous robots that can identify, collect and return samples. NASA needs autonomous robotic capability for future planetary exploration. Photo Credit: (NASA/Bill Ingalls)

Sample Return Robot Centennial Challenge

NASA Image and Video Library

2012-06-16

Team members of "Survey" drive their robot around the campus on Saturday, June 16, 2012 at the Worcester Polytechnic Institute (WPI) in Worcester, Mass. The Survey team was one of the final teams participating in the NASA-WPI Sample Return Robot Centennial Challenge at WPI. Teams were challenged to build autonomous robots that can identify, collect and return samples. NASA needs autonomous robotic capability for future planetary exploration. Photo Credit: (NASA/Bill Ingalls)

Sample Return Robot Centennial Challenge

NASA Image and Video Library

2012-06-15

University of Waterloo (Canada) Robotics Team members test their robot on the practice field one day prior to the NASA-WPI Sample Return Robot Centennial Challenge, Friday, June 15, 2012 at the Worcester Polytechnic Institute in Worcester, Mass. Teams will compete for a $1.5 million NASA prize to build an autonomous robot that can identify, collect and return samples. NASA needs autonomous robotic capability for future planetary exploration. Photo Credit: (NASA/Bill Ingalls)

Sample Return Robot Centennial Challenge

NASA Image and Video Library

2012-06-14

A University of Waterloo Robotics Team member tests their robot on the practice field two days prior to the NASA-WPI Sample Return Robot Centennial Challenge, Thursday, June 14, 2012 at the Worcester Polytechnic Institute in Worcester, Mass. Teams will compete for a $1.5 million NASA prize to build an autonomous robot that can identify, collect and return samples. NASA needs autonomous robotic capability for future planetary exploration. Photo Credit: (NASA/Bill Ingalls)

Return to golf after spine surgery.

PubMed

Abla, Adib A; Maroon, Joseph C; Lochhead, Richard; Sonntag, Volker K H; Maroon, Adara; Field, Melvin

2011-01-01

no published evidence indicates when patients can resume golfing after spine surgery. The objective of this study is to provide data from surveys sent to spine surgeons. a survey of North American Spine Society members was undertaken querying the suggested timing of return to golf. Of 1000 spine surgeons surveyed, 523 responded (52.3%). The timing of recommended return to golf and the reasons were questioned for college/professional athletes and avid and recreational golfers of both sexes. Responses were tallied for lumbar laminectomy, lumbar microdiscectomy, lumbar fusion, and anterior cervical discectomy with fusion. the most common recommended time for return to golf was 4-8 weeks after lumbar laminectomy and lumbar microdiscectomy, 2-3 months after anterior cervical fusion, and 6 months after lumbar fusion. The results showed a statistically significant increase in the recommended time to resume golf after lumbar fusion than after cervical fusion in all patients (p < 0.01). The same holds true for the return to play after cervical fusion compared with either lumbar laminectomy or lumbar microdiscectomy for all golfer types (p < 0.01). There was a statistically significant shorter recommended time for professional and college golfers compared with noncompetitive golfers after lumbar fusion (p < 0.01), anterior cervical discectomy and fusion (p < 0.01), and lumbar microdiscectomy (p < 0.01). the return to golf after spine surgery depends on many variables, including the general well-being of patients in terms of pain control and comfort when golfing. This survey serves as a guide that can assist medical practitioners in telling patients the average times recommended by surgeons across North America regarding return to golf after spine surgery.

Brain Gain or Brain Circulation? U.S. Doctoral Recipients Returning to South Korea

ERIC Educational Resources Information Center

Lee, Jenny J.; Kim, Dongbin

2010-01-01

This study explored the reasons for current reverse mobility patterns in South Korea and how the country benefits from returning U.S. doctoral recipients in the forms of brain gain and brain circulation. Based on interviews of Korean faculty who studied in the U.S., this study found that while the political economy might help to explain why Korean…

THE RETURN OF THE ANDROMEDIDS METEOR SHOWER

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

Wiegert, Paul A.; Brown, Peter G.; Weryk, Robert J.

2013-03-15

The Andromedid meteor shower underwent spectacular outbursts in 1872 and 1885, producing thousands of visual meteors per hour and described as ''stars fell like rain'' in Chinese records of the time. The shower originates from comet 3D/Biela whose disintegration in the mid-1800's is linked to the outbursts, but the shower has been weak or absent since the late 19th century. This shower returned in 2011 December with a zenithal hourly rate of approximately 50, the strongest return in over a hundred years. Some 122 probable Andromedid orbits were detected by the Canadian Meteor Orbit Radar while one possible brighter Andromedidmore » member was detected by the Southern Ontario Meteor Network and several single station possible Andromedids by the Canadian Automated Meteor Observatory. The shower outburst occurred during 2011 December 3-5. The radiant at R.A. +18 Degree-Sign and decl. +56 Degree-Sign is typical of the ''classical'' Andromedids of the early 1800s, whose radiant was actually in Cassiopeia. Numerical simulations of the shower were necessary to identify it with the Andromedids, as the observed radiant differs markedly from the current radiant associated with that shower. The shower's orbital elements indicate that the material involved was released before 3D/Biela's breakup prior to 1846. The observed shower in 2011 had a slow geocentric speed (V{sub G} = 16 km s{sup -1}) and was comprised of small particles: the mean measured mass from the radar is {approx}5 Multiplication-Sign 10{sup -7} kg, corresponding to radii of 0.5 mm at a bulk density of 1000 kg m{sup -3}. Numerical simulations of the parent comet indicate that the meteoroids of the 2011 return of the Andromedids shower were primarily ejected during 3D/Biela's 1649 perihelion passage. The orbital characteristics, radiant, and timing as well as the absence of large particles in the streamlet are all broadly consistent with simulations. However, simulations of the 1649 perihelion passage

19 CFR 145.35 - United States products returned.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 19 Customs Duties 2 2012-04-01 2012-04-01 false United States products returned. 145.35 Section... OF THE TREASURY (CONTINUED) MAIL IMPORTATIONS Special Classes of Merchandise § 145.35 United States products returned. Products of the United States returned after having been exported, which have not been...

19 CFR 145.35 - United States products returned.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 19 Customs Duties 2 2014-04-01 2014-04-01 false United States products returned. 145.35 Section... OF THE TREASURY (CONTINUED) MAIL IMPORTATIONS Special Classes of Merchandise § 145.35 United States products returned. Products of the United States returned after having been exported, which have not been...

19 CFR 145.35 - United States products returned.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 19 Customs Duties 2 2013-04-01 2013-04-01 false United States products returned. 145.35 Section... OF THE TREASURY (CONTINUED) MAIL IMPORTATIONS Special Classes of Merchandise § 145.35 United States products returned. Products of the United States returned after having been exported, which have not been...

19 CFR 145.35 - United States products returned.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 19 Customs Duties 2 2011-04-01 2011-04-01 false United States products returned. 145.35 Section... OF THE TREASURY (CONTINUED) MAIL IMPORTATIONS Special Classes of Merchandise § 145.35 United States products returned. Products of the United States returned after having been exported, which have not been...

19 CFR 145.35 - United States products returned.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 19 Customs Duties 2 2010-04-01 2010-04-01 false United States products returned. 145.35 Section... OF THE TREASURY (CONTINUED) MAIL IMPORTATIONS Special Classes of Merchandise § 145.35 United States products returned. Products of the United States returned after having been exported, which have not been...

26 CFR 1.1502-75 - Filing of consolidated returns.

Code of Federal Regulations, 2013 CFR

2013-04-01

... first consolidated return year. A group which did not file a consolidated return for the immediately... regulations under section 1502. If a group wishes to exercise its privilege of filing a consolidated return... withdrawn after such last day (but the group may change the basis of its return at any time prior to such...

26 CFR 1.1502-75 - Filing of consolidated returns.

Code of Federal Regulations, 2011 CFR

2011-04-01

... first consolidated return year. A group which did not file a consolidated return for the immediately... regulations under section 1502. If a group wishes to exercise its privilege of filing a consolidated return... withdrawn after such last day (but the group may change the basis of its return at any time prior to such...

26 CFR 1.1502-75 - Filing of consolidated returns.

Code of Federal Regulations, 2014 CFR

2014-04-01

... first consolidated return year. A group which did not file a consolidated return for the immediately... regulations under section 1502. If a group wishes to exercise its privilege of filing a consolidated return... withdrawn after such last day (but the group may change the basis of its return at any time prior to such...

26 CFR 1.1502-75 - Filing of consolidated returns.

Code of Federal Regulations, 2012 CFR

2012-04-01

... first consolidated return year. A group which did not file a consolidated return for the immediately... regulations under section 1502. If a group wishes to exercise its privilege of filing a consolidated return... withdrawn after such last day (but the group may change the basis of its return at any time prior to such...

26 CFR 301.6103(j)(1)-1T - Disclosures of return information reflected on returns to officers and employees of the...

Code of Federal Regulations, 2010 CFR

2010-04-01

... 26 Internal Revenue 18 2010-04-01 2010-04-01 false Disclosures of return information reflected on returns to officers and employees of the Department of Commerce for certain statistical purposes and... reflected on returns to officers and employees of the Department of Commerce for certain statistical...

Understanding the dynamic effects of returning patients toward emergency department density

NASA Astrophysics Data System (ADS)

Ahmad, Norazura; Zulkepli, Jafri; Ramli, Razamin; Ghani, Noraida Abdul; Teo, Aik Howe

2017-11-01

This paper presents the development of a dynamic hypothesis for the effect of returning patients to the emergency department (ED). A logical tree from the Theory of Constraint known as Current Reality Tree was used to identify the key variables. Then, a hypothetical framework portraying the interrelated variables and its influencing relationships was developed using causal loop diagrams (CLD). The conceptual framework was designed as the basis for the development of a system dynamics model.

Lightning Characteristics and Lightning Strike Peak Current Probabilities as Related to Aerospace Vehicle Operations

NASA Technical Reports Server (NTRS)

Johnson, Dale L.; Vaughan, William W.

1998-01-01

A summary is presented of basic lightning characteristics/criteria for current and future NASA aerospace vehicles. The paper estimates the probability of occurrence of a 200 kA peak lightning return current, should lightning strike an aerospace vehicle in various operational phases, i.e., roll-out, on-pad, launch, reenter/land, and return-to-launch site. A literature search was conducted for previous work concerning occurrence and measurement of peak lighting currents, modeling, and estimating probabilities of launch vehicles/objects being struck by lightning. This paper presents these results.

Determining return water levels at ungauged coastal sites: a case study for northern Germany

NASA Astrophysics Data System (ADS)

Arns, Arne; Wahl, Thomas; Haigh, Ivan D.; Jensen, Jürgen

2015-04-01

We estimate return periods and levels of extreme still water levels for the highly vulnerable and historically and culturally important small marsh islands known as the Halligen, located in the Wadden Sea offshore of the coast of northern Germany. This is a challenging task as only few water level records are available for this region, and they are currently too short to apply traditional extreme value analysis methods. Therefore, we use the Regional Frequency Analysis (RFA) approach. This originates from hydrology but has been used before in several coastal studies and is also currently applied by the local federal administration responsible for coastal protection in the study area. The RFA enables us to indirectly estimate return levels by transferring hydrological information from gauged to related ungauged sites. Our analyses highlight that this methodology has some drawbacks and may over- or underestimate return levels compared to direct analyses using station data. To overcome these issues, we present an alternative approach, combining numerical and statistical models. First, we produced a numerical multidecadal model hindcast of water levels for the entire North Sea. Predicted water levels from the hindcast are bias corrected using the information from the available tide gauge records. Hence, the simulated water levels agree well with the measured water levels at gauged sites. The bias correction is then interpolated spatially to obtain correction functions for the simulated water levels at each coastal and island model grid point in the study area. Using a recommended procedure to conduct extreme value analyses from a companion study, return water levels suitable for coastal infrastructure design are estimated continuously along the entire coastline of the study area, including the offshore islands. A similar methodology can be applied in other regions of the world where tide gauge observations are sparse.

26 CFR 1.338-10 - Filing of returns.

Code of Federal Regulations, 2014 CFR

2014-04-01

... section 338. (ii) New target in purchasing corporation's consolidated return. If new target is includible... election or other action that must be specified in a timely filed return for new target's first taxable... section, any deemed sale tax consequences are reported on the final return of old target filed for old...

26 CFR 1.338-10 - Filing of returns.

Code of Federal Regulations, 2010 CFR

2010-04-01

... section 338. (ii) New target in purchasing corporation's consolidated return. If new target is includible... election or other action that must be specified in a timely filed return for new target's first taxable..., any deemed sale tax consequences are reported on the final return of old target filed for old target's...

26 CFR 1.338-10 - Filing of returns.

Code of Federal Regulations, 2012 CFR

2012-04-01

... section 338. (ii) New target in purchasing corporation's consolidated return. If new target is includible... election or other action that must be specified in a timely filed return for new target's first taxable... section, any deemed sale tax consequences are reported on the final return of old target filed for old...

26 CFR 1.338-10 - Filing of returns.

Code of Federal Regulations, 2011 CFR

2011-04-01

... section 338. (ii) New target in purchasing corporation's consolidated return. If new target is includible... election or other action that must be specified in a timely filed return for new target's first taxable..., any deemed sale tax consequences are reported on the final return of old target filed for old target's...

26 CFR 1.338-10 - Filing of returns.

Code of Federal Regulations, 2013 CFR

2013-04-01

... section 338. (ii) New target in purchasing corporation's consolidated return. If new target is includible... election or other action that must be specified in a timely filed return for new target's first taxable... section, any deemed sale tax consequences are reported on the final return of old target filed for old...

27 CFR 41.112 - Tax return.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 27 Alcohol, Tobacco Products and Firearms 2 2011-04-01 2011-04-01 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 internal...

Sample Return Robot Centennial Challenge

NASA Image and Video Library

2012-06-16

Panoramic of some of the exhibits available on the campus of the Worcester Polytechnic Institute (WPI) during their "TouchTomorrow" education and outreach event that was held in tandem with the NASA-WPI Sample Return Robot Centennial Challenge on Saturday, June 16, 2012 in Worcester, Mass. The NASA-WPI challenge tasked robotic teams to build autonomous robots that can identify, collect and return samples. NASA needs autonomous robotic capability for future planetary exploration. Photo Credit: (NASA/Anthony Shrout)

Sample Return Robot Centennial Challenge

NASA Image and Video Library

2012-06-16

Posters for the Worcester Polytechnic Institute (WPI) "TouchTomorrow" education and outreach event are seen posted around the campus on Saturday, June 16, 2012 at WPI in Worcester, Mass. The TouchTomorrow event was held in tandem with the NASA-WPI Sample Return Robot Centennial Challenge. The NASA-WPI challenge tasked robotic teams to build autonomous robots that can identify, collect and return samples. NASA needs autonomous robotic capability for future planetary exploration. Photo Credit: (NASA/Bill Ingalls)

Factors influencing return to work after illness in France.

PubMed

Pélissier, C; Fontana, L; Chauvin, F

2014-01-01

Few studies have been published about the factors influencing return to work after sickness absence. To identify medical and occupational factors influencing the type of fitness certificate given by occupational physicians before employees return to work after sickness absence. A cross-sectional study was undertaken over 3 months in several health services in France. Workers undergoing a medical examination before returning to work after a period of sickness absence of at least 3 weeks were included. Medical and occupational factors were collected using a questionnaire. The relationship between different factors and certification of fitness was assessed by univariate and multivariate analyses. Among the 402 workers included, 64% were considered fit to return to work. Being older, strenuous work, prolonged sick leave and fear of returning to work appeared to be negative factors influencing the return to a previous job. In contrast, having an education level higher than secondary school, being satisfied at work, perception of very good health and benefitting from satisfactory professional relationships appeared to favour return to work. We developed a predictive score of not being fit to return to work after illness. Our study highlighted the relationship between medical and occupational factors with problems returning to work. The predictive score may be used by occupational physicians as a screening tool to identify those who are likely to have difficulties returning to work after illness, so that their working conditions can be modified to take this into consideration.

Factors affecting planned return to work after trauma: A prospective descriptive qualitative and quantitative study.

PubMed

Folkard, S S; Bloomfield, T D; Page, P R J; Wilson, D; Ricketts, D M; Rogers, B A

2016-12-01

The use of patient reported outcome measures (PROMs) in trauma is limited. The aim of this pilot study is to evaluate qualitative responses and factors affecting planned return to work following significant trauma, for which there is currently a poor evidence base. National ethical approval was obtained for routine prospective PROMs data collection, including EQ-5D, between Sept 2013 and March 2015 for trauma patients admitted to the Sussex Major Trauma Centre (n=92). 84 trauma patients disclosed their intended return to work at discharge. Additional open questions asked 'things done well' and 'things to be improved'. EQ-5D responses were valued using the time trade-off method. Statistical analysis between multiple variables was completed by ANOVA, and with categorical categories by Chi squared analysis. Only 18/68 of patients working at admission anticipated returning to work within 14days post-discharge. The injury severity scores (ISS) of those predicting return to work within two weeks and those predicting return to work longer than two weeks were 14.17 and 13.59, respectively. Increased physicality of work showed a trend towards poorer return to work outcomes, although non-significant in Chi-squared test in groups predicting return in less than or greater than two weeks (4.621, p=0.2017ns). No significant difference was demonstrated in the comparative incomes of patients with different estimated return to work outcomes (ANOVA r 2 =0.001, P=0.9590ns). EQ-5D scores were higher in those predicting return to work within two weeks when compared to greater than two weeks. Qualitative thematic content analysis of open responses was possible for 66/92 of respondents. Prominent positive themes were: care, staff, professionalism, and communication. Prominent negative themes were: food, ward response time, and communication. This pilot study highlights the importance of qualitative PROMs analysis in leading patient-driven improvements in trauma care. We provide standard

26 CFR 301.6103(k)(9)-1 - Disclosure of returns and return information relating to payment of tax by credit card and debit...

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 relating to payment of tax by credit card and debit card. 301.6103(k)(9)-1 Section 301.6103(k)(9)-1... ADMINISTRATION PROCEDURE AND ADMINISTRATION Information and Returns Returns and Records § 301.6103(k)(9)-1...

26 CFR 301.6103(k)(9)-1 - Disclosure of returns and return information relating to payment of tax by credit card and debit...

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 relating to payment of tax by credit card and debit card. 301.6103(k)(9)-1 Section 301.6103(k)(9)-1... ADMINISTRATION PROCEDURE AND ADMINISTRATION Information and Returns Returns and Records § 301.6103(k)(9)-1...

26 CFR 301.6103(k)(9)-1 - Disclosure of returns and return information relating to payment of tax by credit card and debit...

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 relating to payment of tax by credit card and debit card. 301.6103(k)(9)-1 Section 301.6103(k)(9)-1... ADMINISTRATION PROCEDURE AND ADMINISTRATION Information and Returns Returns and Records § 301.6103(k)(9)-1...

26 CFR 301.6103(k)(9)-1 - Disclosure of returns and return information relating to payment of tax by credit card and debit...

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 relating to payment of tax by credit card and debit card. 301.6103(k)(9)-1 Section 301.6103(k)(9)-1... ADMINISTRATION PROCEDURE AND ADMINISTRATION Information and Returns Returns and Records § 301.6103(k)(9)-1...

26 CFR 301.6103(k)(9)-1 - Disclosure of returns and return information relating to payment of tax by credit card and debit...

Code of Federal Regulations, 2010 CFR

2010-04-01

... 26 Internal Revenue 18 2010-04-01 2010-04-01 false Disclosure of returns and return information relating to payment of tax by credit card and debit card. 301.6103(k)(9)-1 Section 301.6103(k)(9)-1... ADMINISTRATION PROCEDURE AND ADMINISTRATION Information and Returns Returns and Records § 301.6103(k)(9)-1...

Return of separated children: the impact of Dutch policies.

PubMed

Kromhout, Mariska

2011-01-01

In many European countries, both the voluntary and the forced return of rejected asylum seekers are problematic. In the case of separated children, the difficulties seem to be even greater. In the Netherlands, many of these children disappear from the reception centres for unknown destinations, instead of returning to their home country. The new, stricter return policies adopted by the Dutch government in recent years have not (yet) changed this situation.In an explorative study of separated children aged between 15 and 18, the implementation and results of these policies were studied. The impact of the activities designed to promote voluntary return appeared to be very limited. Most separated young people did not want to consider return and did not take any action in this regard. Forced return rarely constituted a viable alternative. These findings may be explained by several factors. Among other things, considerations pertaining to personal security, family circumstances, and structural conditions in the countries of origin influence both the attitudes and behaviours of separated children, and host government policies. Moreover, many children were not willing to discuss their return with the youth care workers who were supposed to discuss and promote a voluntary return with them. The fact that most of the young people were allowed to stay in the reception centres until their eighteenth birthday enabled them to postpone making a final decision. A forced return was hindered by such obstacles as the absence of documents and the lack of appropriate care in the country of origin. More insight into the backgrounds of separated children and the (im)possibilities regarding their return seems necessary to be able to design more effective return policies.

Long-term return behavior of Chinese whole blood donors.

PubMed

Guo, Nan; Wang, Jingxing; Yu, Qilu; Yang, Tonghan; Dong, Xiangdong; Wen, Guoxin; Tiemuer, Mei-hei-li; Li, Julin; He, Weilan; Lv, Yunlai; Ma, Hongli; Wen, Xiuqiong; Huang, Mei; Ness, Paul; Liu, Jing; Wright, David J; Nelson, Kenrad; Shan, Hua

2013-09-01

It is important to understand donor return behavior to maintain sufficient numbers of blood donors in developing countries where blood supplies are often inadequate. A total of 54,267 whole blood (WB) donors who donated between January 1 and March 31, 2008, at the five blood centers in China were followed for 2.5 years. Logistic regression was conducted to identify factors associated with their return behavior. A recurrent-event Cox proportional-hazard model was used to evaluate the overall effect of demographic variables and return behavior among first-time donors. Donors with previous donation history were more likely to return and the number of previous returns was positively associated with future return (odds ratios, 3.31, 4.82, and 8.16 for one, two to three, and more than three times compared to none). Thirty-four percent of donors (first-time donor, 21%; repeat donor, 54%) made at least one return donation, with 14% returning in the first 9 months. The multivariable logistic regression model for all WB donors and the Cox proportional hazard model for first-time donors showed consistent predictors for return: female sex, older age (≥ 25 years), larger volume (300 or 400 mL), and donating in satellite collection site. Encouraging first-time donors to make multiple donations is important for keeping adequate blood supply. The finding that first-time and repeat donors shared the same predictors for return indicates that retention strategies on repeat donors may be effective on first-time donors. Studies on motivators and barriers to return are needed, so that successful retention strategies can be tailored. © 2013 American Association of Blood Banks.

14 CFR 49.21 - Return of original conveyance.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Return of original conveyance. 49.21... RECORDING OF AIRCRAFT TITLES AND SECURITY DOCUMENTS General § 49.21 Return of original conveyance. If a person submitting a conveyance for recording wants the original returned to him, he must submit a true...

38 CFR 3.1003 - Returned and canceled checks.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Returned and canceled... canceled checks. Where the payee of a check for benefits has died prior to negotiating the check, the check shall be returned to the issuing office and canceled. (a) The amount represented by the returned check...

Return to sport following tibial plateau fractures: A systematic review

PubMed Central

Robertson, Greg A J; Wong, Seng J; Wood, Alexander M

2017-01-01

AIM To systemically review all studies reporting return to sport following tibial plateau fracture, in order to provide information on return rates and times to sport, and to assess variations in sporting outcome for different treatment methods. METHODS A systematic search of CINAHAL, Cochrane, EMBASE, Google Scholar, MEDLINE, PEDro, Scopus, SPORTDiscus and Web of Science was performed in January 2017 using the keywords “tibial”, “plateau”, “fractures”, “knee”, “athletes”, “sports”, “non-operative”, “conservative”, “operative”, “return to sport”. All studies which recorded return rates and times to sport following tibial plateau fractures were included. RESULTS Twenty-seven studies were included: 1 was a randomised controlled trial, 7 were prospective cohort studies, 16 were retrospective cohort studies, 3 were case series. One study reported on the outcome of conservative management (n = 3); 27 reported on the outcome of surgical management (n = 917). Nine studies reported on Open Reduction Internal Fixation (ORIF) (n = 193), 11 on Arthroscopic-Assisted Reduction Internal Fixation (ARIF) (n = 253) and 7 on Frame-Assisted Fixation (FRAME) (n = 262). All studies recorded “return to sport” rates. Only one study recorded a “return to sport” time. The return rate to sport for the total cohort was 70%. For the conservatively-managed fractures, the return rate was 100%. For the surgically-managed fractures, the return rate was 70%. For fractures managed with ORIF, the return rate was 60%. For fractures managed with ARIF, the return rate was 83%. For fractures managed with FRAME was 52%. The return rate for ARIF was found to be significantly greater than that for ORIF (OR 3.22, 95%CI: 2.09-4.97, P < 0.001) and for FRAME (OR 4.33, 95%CI: 2.89-6.50, P < 0.001). No difference was found between the return rates for ORIF and FRAME (OR 1.35, 95%CI: 0.92-1.96, P = 0.122). The recorded return time was 6.9 mo (median), from a study

Does the private sector receive an excessive return from investments in health care infrastructure projects? Evidence from the UK.

PubMed

Vecchi, Veronica; Hellowell, Mark; Gatti, Stefano

2013-05-01

This paper is concerned with the cost-efficiency of Private Finance Initiatives (PFIs) in the delivery of hospital facilities in the UK. We outline a methodology for identifying the "fair" return on equity, based on the Weighted Average Cost of Capital (WACC) of each investor. We apply this method to assess the expected returns on a sample of 77 contracts signed between 1997 and 2011 by health care provider organisations in the UK. We show that expected returns are in general in excess of the WACC benchmarks. The findings highlight significant problems in current procurement practices and the methodologies by which bids are assessed. To minimise the financial impact of hospital investments on health care systems, a regulatory regime must ensure that expected returns are set at the "fair" rate. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Jump-and-return sandwiches: A new family of binomial-like selective inversion sequences with improved performance.

PubMed

Brenner, Tom; Chen, Johnny; Stait-Gardner, Tim; Zheng, Gang; Matsukawa, Shingo; Price, William S

2018-03-01

A new family of binomial-like inversion sequences, named jump-and-return sandwiches (JRS), has been developed by inserting a binomial-like sequence into a standard jump-and-return sequence, discovered through use of a stochastic Genetic Algorithm optimisation. Compared to currently used binomial-like inversion sequences (e.g., 3-9-19 and W5), the new sequences afford wider inversion bands and narrower non-inversion bands with an equal number of pulses. As an example, two jump-and-return sandwich 10-pulse sequences achieved 95% inversion at offsets corresponding to 9.4% and 10.3% of the non-inversion band spacing, compared to 14.7% for the binomial-like W5 inversion sequence, i.e., they afforded non-inversion bands about two thirds the width of the W5 non-inversion band. Copyright © 2018 Elsevier Inc. All rights reserved.

Mathematical Formulation of the Remote Electric and Magnetic Emissions of the Lightning Dart Leader and Return Stroke

NASA Astrophysics Data System (ADS)

Thiemann, Edward M. B.

Lightning detection and geolocation networks have found widespread use by the utility, air traffic control and forestry industries as a means of locating strikes and predicting imminent recurrence. Accurate lightning geolocation requires detecting VLF radio emissions at multiple sites using a distributed sensor network with typical baselines exceeding 150 km, along with precision time of arrival estimation to triangulate the origin of a strike. The trend has been towards increasing network accuracy without increasing sensor density by incorporating precision GPS synchronized clocks and faster front-end signal processing. Because lightning radio waveforms evolve as they propagate over a finitely conducting earth, and that measurements for a given strike may have disparate propagation path lengths, accurate models are required to determine waveform fiducials for precise strike location. The transition between the leader phase and return stroke phase may offer such a fiducial and warrants quantitative modeling to improve strike location accuracy. The VLF spectrum of the ubiquitous downward negative lightning strike is able to be modeled by the transfer of several Coulombs of negative charge from cloud to ground in a two-step process. The lightning stepped leader ionizes a plasma channel downward from the cloud at a velocity of approximately 0.05c, leaving a column of charge in its path. Upon connection with a streamer, the subsequent return stroke initiates at or near ground level and travels upward at an average but variable velocity of 0.3c. The return stroke neutralizes any negative charge along its path. Subsequent dart leader and return strokes often travel smoothly down the heated channel left by a preceding stroke, lacking the halting motion of the preceding initial stepped leader and initial return stroke. Existing lightning models often neglect the leader current and rely on approximations when solving for the return stroke. In this thesis, I present an

Lost in translation: returning germline genetic results in genome-scale cancer research.

PubMed

Johns, Amber L; McKay, Skye H; Humphris, Jeremy L; Pinese, Mark; Chantrill, Lorraine A; Mead, R Scott; Tucker, Katherine; Andrews, Lesley; Goodwin, Annabel; Leonard, Conrad; High, Hilda A; Nones, Katia; Patch, Ann-Marie; Merrett, Neil D; Pavlakis, Nick; Kassahn, Karin S; Samra, Jaswinder S; Miller, David K; Chang, David K; Pajic, Marina; Pearson, John V; Grimmond, Sean M; Waddell, Nicola; Zeps, Nikolajs; Gill, Anthony J; Biankin, Andrew V

2017-04-28

The return of research results (RoR) remains a complex and well-debated issue. Despite the debate, actual data related to the experience of giving individual results back, and the impact these results may have on clinical care and health outcomes, is sorely lacking. Through the work of the Australian Pancreatic Cancer Genome Initiative (APGI) we: (1) delineate the pathway back to the patient where actionable research data were identified; and (2) report the clinical utilisation of individual results returned. Using this experience, we discuss barriers and opportunities associated with a comprehensive process of RoR in large-scale genomic research that may be useful for others developing their own policies. We performed whole-genome (n = 184) and exome (n = 208) sequencing of matched tumour-normal DNA pairs from 392 patients with sporadic pancreatic cancer (PC) as part of the APGI. We identified pathogenic germline mutations in candidate genes (n = 130) with established predisposition to PC or medium-high penetrance genes with well-defined cancer associated syndromes or phenotypes. Variants from candidate genes were annotated and classified according to international guidelines. Variants were considered actionable if clinical utility was established, with regard to prevention, diagnosis, prognostication and/or therapy. A total of 48,904 germline variants were identified, with 2356 unique variants undergoing annotation and in silico classification. Twenty cases were deemed actionable and were returned via previously described RoR framework, representing an actionable finding rate of 5.1%. Overall, 1.78% of our cohort experienced clinical benefit from RoR. Returning research results within the context of large-scale genomics research is a labour-intensive, highly variable, complex operation. Results that warrant action are not infrequent, but the prevalence of those who experience a clinical difference as a result of returning individual results is

27 CFR 25.211 - Beer returned to brewery.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Beer returned to brewery..., DEPARTMENT OF THE TREASURY LIQUORS BEER Beer Returned to Brewery § 25.211 Beer returned to brewery. (a) General. Beer, produced in the United States, on which the brewer has paid or determined the tax may be...

Supporting Women Returning to Work: A European Perspective.

ERIC Educational Resources Information Center

Shepherd, Jan; Saxby-Smith, Sue

A 2-year project examined the effectiveness of courses for returning workers in enabling women to make a sustained return to paid employment in the following countries: France; Spain; Ireland; and the United Kingdom. In each country, a short foundation-level program and a longer accredited return-to-work program were selected for evaluation.…

27 CFR 25.211 - Beer returned to brewery.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Beer returned to brewery..., DEPARTMENT OF THE TREASURY LIQUORS BEER Beer Returned to Brewery § 25.211 Beer returned to brewery. (a) General. Beer, produced in the United States, on which the brewer has paid or determined the tax may be...

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 chapter...

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) Effective...

Return to a Broadcast Newsroom to Stay Current in the Field.

ERIC Educational Resources Information Center

Youngblood, Steven

1999-01-01

Describes how the author, a broadcasting educator, worked as a summer intern at a professional TV station in order to keep his instruction current, and to keep up on the latest stylistic and technological changes in the business. Discusses the benefits of doing so, and notes some useful information learned. (SR)

Returning to sports after a back injury

MedlinePlus

... medlineplus.gov/ency/patientinstructions/000518.htm Returning to sports after a back injury To use the sharing ... Back pain - returning to sports Which Type of Sport is Best? In deciding when and if to ...

The Extinction and Return of Fear of Public Speaking.

PubMed

Laborda, Mario A; Schofield, Casey A; Johnson, Emily M; Schubert, Jessica R; George-Denn, Daniel; Coles, Meredith E; Miller, Ralph R

2016-11-01

Prior studies indicate extinguished fear often partially returns when participants are later tested outside the extinction context. Cues carried from the extinction context to the test context sometimes reduce return of fear, but it is unclear whether such extinction cues (ECs) reduce return of fear of public speaking. Here we assessed return of fear of public speaking, and whether either of two types of ECs can attenuate it. Participants gave speeches of increasing difficulty during an exposure practice session and were tested 2 days later in a different context. Testing occurred in the presence of physical ECs, after mentally rehearsing the exposure session, or without either reminder. Practice reduced fear of public speaking, but fear partially returned at test. Neither physical nor mental ECs reduced partial return of fear of public speaking. The return of extinguished fear of public speaking, although small, was reliable, but not appreciably sensitive to presence of ECs. © The Author(s) 2016.

Return to Training and Playing After Acute Lisfranc Injuries in Elite Professional Soccer and Rugby Players.

PubMed

Deol, Rupinderbir Singh; Roche, Andrew; Calder, James D F

2016-01-01

Lisfranc joint injuries are increasingly recognized in elite soccer and rugby players. Currently, no evidence-based guidelines exist on time frames for return to training and competition after surgical treatment. To assess the time to return to training and playing after Lisfranc joint injuries. Case series; Level of evidence, 4. A consecutive series of 17 professional soccer and rugby players in the English Premier/Championship leagues was assessed using prospectively collected data. All were isolated injuries sustained during training or competitive matches. Each player had clinical and radiological evidence of an unstable Lisfranc injury and required surgical treatment. A standardized postoperative regimen was used. The minimum follow-up time was 2 years. Clinical and radiological follow-up was obtained in all 17 players. Seven players had primarily ligamentous injuries, and 10 had bony injuries. The time from injury to fixation ranged from 8 to 31 days, and hardware was removed at 16 weeks postoperatively. One athlete retired after a ligamentous injury; the remaining 16 players returned to training and full competition. Excluding the retired player, the mean time to return to training was 20.1 weeks (range, 18-24 weeks) and to full competition was 25.3 weeks (range, 21-31 weeks). There was a significant difference between the mean time to return to competition for rugby (27.8 weeks) and soccer players (24.1 weeks; P = .02) and for ligamentous (22.5 weeks) compared with bony injuries (26.9 weeks; P = .003). Three patients suffered deep peroneal nerve sensation loss, from which 1 patient did not fully recover. Return to competitive elite-level soccer and rugby is possible after surgically treated Lisfranc injuries. Return to training can take up to 24 weeks and return to playing up to 31 weeks, with bony injuries taking longer. © 2015 The Author(s).

Sample Return Robot Centennial Challenge

NASA Image and Video Library

2012-06-16

Visitors, some with their dogs, line up to make their photo inside a space suit exhibit during the Worcester Polytechnic Institute (WPI) "TouchTomorrow" education and outreach event that was held in tandem with the NASA-WPI Sample Return Robot Centennial Challenge on Saturday, June 16, 2012 in Worcester, Mass. The NASA-WPI challenge tasked robotic teams to build autonomous robots that can identify, collect and return samples. NASA needs autonomous robotic capability for future planetary exploration. Photo Credit: (NASA/Bill Ingalls)

Sample Return Robot Centennial Challenge

NASA Image and Video Library

2012-06-16

The bronze statue of the goat mascot for Worcester Polytechnic Institute (WPI) named "Gompei" is seen wearing a staff t-shirt for the "TouchTomorrow" education and outreach event that was held in tandem with the NASA-WPI Sample Return Robot Centennial Challenge on Saturday, June 16, 2012 in Worcester, Mass. The challenge tasked robotic teams to build autonomous robots that can identify, collect and return samples. NASA needs autonomous robotic capability for future planetary exploration. Photo Credit: (NASA/Bill Ingalls)

Sample Return Robot Centennial Challenge

NASA Image and Video Library

2012-06-15

Intrepid Systems robot, foreground, and the University of Waterloo (Canada) robot, take to the practice field on Friday, June 15, 2012 at the Worcester Polytechnic Institute (WPI) in Worcester, Mass. Robot teams will compete for a $1.5 million NASA prize in the NASA-WPI Sample Return Robot Centennial Challenge at WPI. Teams have been challenged to build autonomous robots that can identify, collect and return samples. NASA needs autonomous robotic capability for future planetary exploration. Photo Credit: (NASA/Bill Ingalls)

Student-Teacher-Researcher Collaboration through NOAA's Adopt A Drifter Program

NASA Astrophysics Data System (ADS)

Stanitski, D.; Cronin, M. F.; Malan, N.; Ansorge, I. J.; Beal, L. M.; Hermes, J. C.; Lumpkin, R.; Dolk, S.

2016-02-01

NOAA scientists and students in South Africa and the USA performed oceanographic experiments by deploying two surface drifting buoys in the Agulhas Current east of South Africa with the intent to determine the direction and path of each drifter's movement. The drifters were provided by the Global Drifter Program and the education component supported by the NOAA Adopt A Drifter Program (ADP). In a "surface dispersion" experiment, students in the classes that co-adopted the pair of surface drifters developed hypotheses about the drifters' paths, including whether they might drift into the Atlantic, Indian, Southern, or Pacific Oceans. They hypothesized why, when, and where the two drifters would separate. As part of the ADP, the collaborating schools tracked the drifters together via the internet. Several months after the drifters were deployed, a NOAA researcher discussed the surprising results with the collaborating students and teachers, including K-12 school children in George, Western Cape and Mossel Bay, South Africa and Bethesda, Maryland USA. One drifter pair had an interesting path. Although deployed in the center of the Agulhas Current, the pair became entrained in a submesoscale cyclonic vortex that formed as the jet flowed across the continental shelf break. The submesoscale vortex (with the drifter pair) then separated from the jet and leaked into the Atlantic Ocean. The eddy was visible in high-resolution satellite images of the sea surface temperature, but was not resolved in satellite altimetry fields. As discussed in a paper led by University of Cape Town graduate student Neil Malan currently under review, this implies that estimates of Agulhas leakage may be underestimated as they do not include this new pathway provided by submesoscale cyclonic vortices. Data from the adopted drifting buoys contribute to the Global Drifter Program, a component of the Global Ocean Observing System, and can be viewed from the NOAA Adopt a Drifter Program tracking

NASA Sample Return Missions: Recovery Operations

NASA Technical Reports Server (NTRS)

Pace, L. F.; Cannon, R. E.

2017-01-01

The Utah Test and Training Range (UTTR), southwest of Salt Lake City, Utah, is the site of all NASA unmanned sample return missions. To date these missions include the Genesis solar wind samples (2004) and Stardust cometary and interstellar dust samples (2006). NASA’s OSIRIS-REx Mission will return its first asteroid sample at UTTR in 2023.

26 CFR 53.7701-1 - Tax return preparer.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 26 Internal Revenue 17 2011-04-01 2011-04-01 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 this...

Project Return and Babygram Hospital Outreach, 1993-94.

ERIC Educational Resources Information Center

Weiler, Jeanne

Project Return, a dropout recovery program to assist pregnant and parenting teenagers and parents of elementary school children to return to school, was first implemented in 1989-90, and by 1993-94 had expanded to serve 19 sites in New York City. The Babygram Hospital Outreach program, an outgrowth of Project Return, operated in 12 hospitals and…

26 CFR 301.7701-15 - Tax return preparer.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 26 Internal Revenue 18 2010-04-01 2010-04-01 false Tax return preparer. 301.7701-15 Section 301... ADMINISTRATION PROCEDURE AND ADMINISTRATION Definitions § 301.7701-15 Tax return preparer. (a) In general. A tax... prepare for compensation, all or a substantial portion of any return of tax or any claim for refund of tax...

31 CFR 10.28 - Return of client's records.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Return of client's records. 10.28... § 10.28 Return of client's records. (a) In general, a practitioner must, at the request of a client, promptly return any and all records of the client that are necessary for the client to comply with his or...

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 this...

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 date...

Sample Return: What Happens to the Samples on Earth?

NASA Technical Reports Server (NTRS)

McNamara, Karen

2010-01-01

As space agencies throughout the world turn their attention toward human exploration of the Moon, Mars, and the solar system beyond, there has been an increase in the number of robotic sample return missions proposed as precursors to these human endeavors. In reality, however, we, as a global community, have very little experience with robotic sample return missions: 3 of the Russian Luna Missions successfully returned lunar material in the 1970s; 28 years later, in 2004, NASA s Genesis Mission returned material from the solar wind; and in 2006, NASA s Stardust Mission returned material from the Comet Wild2. [Note: The Japanese Hyabusa mission continues in space with the hope of returning material from the asteroid 25143 Itokawa.] We launch many spacecraft to LEO and return them to Earth. We also launch spacecraft beyond LEO to explore the planets, our solar system, and beyond. Some even land on these bodies. But these do not return. So as we begin to contemplate the sample return missions of the future, some common questions arise: "What really happens when the capsule returns?" "Where does it land?" "Who retrieves it and just how do they do that?" "Where does it go after that?" "How do the scientists get the samples?" "Do they keep them?" "Who is in charge?" The questions are nearly endless. The goal of this paper/presentation is to uncover many of the mysteries of the post-return phase of a mission - from the time the return body enters the atmosphere until the mission ends and the samples become part of a long term collection. The discussion will be based largely on the author s own experience with both the Genesis and Stardust missions. Of course, these two missions have a great deal in common, being funded by the same NASA Program (Discovery) and having similar team composition. The intent, however, is to use these missions as examples in order to highlight the general requirements and the challenges in defining and meeting those requirements for the final

Attitudes and intentions of current anaesthetic trainees.

PubMed

Fröhlich, S; Moriarty, J

2013-03-01

We report the results of a survey of Irish anaesthetic specialist trainees to establish their future training intentions, their interest in seeking a Consultant position in Ireland and identification of factors that may reduce the attractiveness of future employment in the HSE. 149 responses were received (71% of trainees). 137 (92%) are likely to complete further training abroad, but only 24 (16.1%) are definitely planning to return to work in Ireland. Factors, in order of importance that influence their return to Ireland include equivalence of all Consultants, salary level and availability of flexible work practices. Almost all (131 - 91%) would only consider working in Ireland at Consultant level. These results reveal that the current cohort of specialist trainees do not consider Ireland an attractive place to work, and any further diminution of the current Consultant grade will only serve to worsen this perception.

New Media in Student Recruiting: Bright Promise, Current Realities.

ERIC Educational Resources Information Center

Stoner, Michael

1996-01-01

Explores current options for using the World Wide Web and interactive media for undergraduate recruiting. Discusses some technological issues concerning market penetration of technologies, and explores the issue of return on investment. Currently available data do not support spending a lot of money on Web pages, although CD-ROM or floppy disks…

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.

Returns on Investment in California County Departments of Public Health.

PubMed

Brown, Timothy T

2016-08-01

To estimate the average return on investment for the overall activities of county departments of public health in California. 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. The estimated return on investment from $1 invested in county departments of public health in California ranges from $67.07 to $88.21. 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.

Apparatus for producing voltage and current pulses

DOEpatents

Kirbie, Hugh; Dale, Gregory E.

2010-12-21

An apparatus having one or more modular stages for producing voltage and current pulses. Each module includes a diode charging means to charge a capacitive means that stores energy. One or more charging impedance means are connected to the diode charging means to provide a return current pathway. A solid-state switch discharge means, with current interruption capability, is connected to the capacitive means to discharge stored energy. Finally, a control means is provided to command the switching action of the solid-state switch discharge means.

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.

Merits of a Locality Sample for Accomplishing Mars Exploration Goals: The First Sample Return Mission

NASA Astrophysics Data System (ADS)

Draper, D. S.; Bogard, D. D.; Agee, C. B.; McKay, G. A.; Jones, J. H.

2002-05-01

A major stumbling block to a Mars sample return (MSR) mission is the seemingly prohibitive cost of maximizing sample diversity. The use of rovers, sophisticated on-board instrumentation, and various sample selection techniques are perceived by some to be necessary to maximize the scientific return by making it possible to acquire as diverse a suite of samples as possible. Here, we argue that many key science goals of the Mars Exploration Program may be accomplished by returning only a "locality sample" at a well-chosen landing site. A locality sample would be local regolith consisting of soil, windblown fines, and lithic fragments (plus Martian atmosphere). We argue that even the simplest sample return mission could revolutionize our understanding of the planet, without requiring the large outlays for technology development currently envisioned. By the time a MSR mission could realistically be flown, it is reasonable to expect that information from the Mars Odyssey, Mars Express, 2003 Mars Exploration Rovers, and 2005 Mars Reconnaissance Orbiter will be sufficient to make a good choice of landing site. Returned samples of Martian regolith have the potential to answer key questions of fundamental importance to the Mars Exploration Program: The search for life; understanding the role and history of water and other volatiles; helping to interpret remotely-sensed spectral data; and understanding the planet as a system. The value of such samples has been studied exhaustively for decades and detailed in publications dating back at least to 1974. A locality sample can further the search for life by identifying, among other things, trace quantities of surface organics, biogenic elements and their isotopic compositions, evidence for water in the form of hydrous minerals and/or cements, the nature of the Martian soil oxidant, trace biomarkers, and evidence for clay-forming processes. The role of water will be better understood by revealing, in addition, whether interactions

Return-to-Work Self-Efficacy and Actual Return to Work Among Long-Term Sick-Listed Employees.

PubMed

Volker, D; Zijlstra-Vlasveld, M C; Brouwers, E P M; van Lomwel, A G C; van der Feltz-Cornelis, C M

2015-06-01

Considering the costs incurred by sickness absence and the implications for the workers' quality of life, a fast return to work (RTW) is important. Self-efficacy (SE) seems to be an important predictor of RTW for employees with mental health problems. The predictive value of return-to-work self-efficacy (RTW-SE) has not been examined in employees on long-term sickness absence due to any cause. The aim of this study is to investigate whether RTW-SE is a predictor of time to RTW in long-term sick-listed employees with all-cause sickness absence. Furthermore, the relative contribution of RTW-SE in predicting RTW will be examined compared to health-related, job-related and personal factors. In a longitudinal study, sick-listed employees who were currently on sick leave for more than 4 weeks filled out a self-report questionnaire. Demographics, health-related, personal, and job-related factors, and RTW-SE were measured. Employees were followed for 2 years to determine the duration until full RTW. Cox proportional hazards regression analyses were used to identify factors associated with time to RTW. Data were collected from 493 sick-listed employees. RTW-SE was a significant predictor of RTW. In a multivariate model, low RTW-SE, the thought of not being able to work while having symptoms (illness behaviour) and having chronic medical conditions were predictors of a longer duration until RTW. When guiding long-term sick-listed employees, it is important to focus on factors such as SE and illness behaviour, instead of just focusing on the symptoms of the sick-listed employee.

Barriers to return to work after burn injuries.

PubMed

Esselman, Peter C; Askay, Shelley Wiechman; Carrougher, Gretchen J; Lezotte, Dennis C; Holavanahalli, Radha K; Magyar-Russell, Gina; Fauerbach, James A; Engrav, Loren H

2007-12-01

To identify barriers to return to work after burn injury as identified by the patient. A cohort study with telephone interview up to 1 year. Hospital-based burn centers at 3 national sites. Hospitalized patients (N=154) meeting the American Burn Association criteria for major burn injury, employed at least 20 hours a week at the time of injury, and with access to a telephone after discharge. Patients were contacted via telephone every 2 weeks up to 4 months, then monthly up to 1 year after discharge. A return to work survey was used to identify barriers that prevented patients from returning to work. A graphic rating scale determined the impact of each barrier. By 1 year, 79.7% of patients returned to work. Physical and wound issues were barriers early after discharge. Although physical abilities continued to be a significant barrier up to 1 year, working conditions (temperature, humidity, safety) and psychosocial factors (nightmares, flashbacks, appearance concerns) became important issues in those with long-term disability. The majority of patients return to work after a burn injury. Although physical and work conditions are important barriers, psychosocial issues need to be evaluated and treated to optimize return to work.

Laboratory simulation of field-aligned currents

NASA Technical Reports Server (NTRS)

Wessel, Frank J.; Rostoker, Norman

1993-01-01

A summary of progress during the period Apr. 1992 to Mar. 1993 is provided. Objectives of the research are (1) to simulate, via laboratory experiments, the three terms of the field-aligned current equation; (2) to simulate auroral-arc formation processes by configuring the boundary conditions of the experimental chamber and plasma parameters to produce highly localized return currents at the end of a field-aligned current system; and (3) to extrapolate these results, using theoretical and computational techniques, to the problem of magnetospheric-ionospheric coupling and to compare them with published literature signatures of auroral-arc phenomena.

Returns on equity for not-for-profit hospitals.