Wake-Induced Aerodynamics on a Trailing Aircraft

NASA Technical Reports Server (NTRS)

Mendenhall, Michael R.; Lesieutre, Daniel J.; Kelly, Michael J.

2016-01-01

NASA conducted flight tests to measure the exhaust products from alternative fuels using a DC-8 transport aircraft and a Falcon business jet. An independent analysis of the maximum vortex-induced loads on the Falcon in the DC-8 wake was conducted for pre-flight safety analysis and to define safe trail distances for the flight tests. Static and dynamic vortex-induced aerodynamic loads on the Falcon were predicted at a matrix of locations aft of the DC-8 under flight-test conditions, and the maximum loads were compared with design limit loads to assess aircraft safety. Trajectory simulations for the Falcon during close encounters with the DC-8 wake were made to study the vortex-induced loads during traverses of the DC-8 primary trailing vortex. A parametric study of flight traverses through the trailing vortex was conducted to assess Falcon flight behavior and motion characteristics.

A wind tunnel investigation of the wake near the trailing edge of a deflected externally blown flap. [on a jet powered STOL transport aircraft

NASA Technical Reports Server (NTRS)

Johnson, W. G., Jr.; Kardas, G. E.

1974-01-01

The model tested was a general research model of a swept-wing, jet-powered STOL transport with externally blown flaps. The model was tested with four engine simulators mounted on pylons under the wing. Tests were conducted in the V/STOL tunnel over an angle of attack range of 0 deg to 16 deg and a thrust coefficient range from 0 to approximately 4 at a Reynolds number of 0.461 x 1 million based on the wing reference chord. The results of this investigation are presented primarily as plots of the individual velocity vectors obtained from the wake survey. These data are used to extend an earlier analysis to isolate the effects of the engine thrust on the behavior of the flow at the flap trailing edge. Results of a comparison with a jet-flap theory are also shown.

Studying the Structure of Condensables Jupiter’s 24deg Jet

NASA Astrophysics Data System (ADS)

Flom, Abigail; Sankar, Ramanakumar; Palotai, Csaba J.; Dowling, Timothy E.

2017-10-01

Simulations of the atmospheres of Jovian planets can be used to check our current understanding of the physics of their atmospheres. Such studies have been performed in the past, but the development of cloud microphysics models allows us to gain new insight in how the clouds form and behave in areas of interest. This study conducts high resolution cloudy simulations of the 24 degree north high speed jet for a period of 200 days. The models were created using the Explicit Planetary Isentropic_Coordinate (EPIC) general circulation model (Dowling et al 1998, 2006) that includes full hydrological cycle for multiple condensible species (Palotai and dowling 2008, Palotai et al 2016). This builds off of work presented by our group last year at DPS. The simulations were run under various conditions again in order to test what parameters led to stable simulations. These results help describe which physical parameters can lead to stable high speed jets and how water and ammonia behave within these features. Reference: [1] T. Dowling, A. Fischer, P. Gierasch, J. Harrington, R. Lebeau, and C. Santori. The explicit planetary isentropic-coordinate (epic) atmospheric model. Icarus, 1998. [2] T. E. Dowling, M. E. Bradley, E. Colon, J. Kramer, R. P. LeBeau, G. C. H. Lee, T. I. Mattox, R. Morales-Juberias, C. J. Palotai, V. k. Parimi, and A. P. Showman. The epic atmospheric model with an isentropic/terrain-following hybrid vertical coordinate. Icarus, 182:259-273, may 2006.[3] C. Palotai and T. E. Dowling. Addition of water and ammonia cloud microphysics to the epic model. Icarus, 2008.[4] C. J. Palotai, R. P. Le Beau, R. Shankar, A. Flom, J. Lashley, and T. McCabe. A cloud microphysics model for the gas giant planets. In AAS/Division for Planetary Sciences Meeting Abstracts, 2016.

Numerical Investigation of Flow Around Rectangular Cylinders with and Without Jets

NASA Technical Reports Server (NTRS)

Tiwari, S. N .; Pidugu, S. B.

1999-01-01

The problem of flow past bluff bodies was studied extensively in the past. The problem of drag reduction is very important in many high speed flow applications. Considerable work has been done in this subject area in case of circular cylinders. The present study attempts to investigate the feasibility of drag reduction on a rectangular cylinder by flow injection by flow injection from the rear stagnation region. The physical problem is modeled as two-dimensional body and numerical analysis is carried out with and without trailing jets. A commercial code is used for this purpose. Unsteady computation is performed in case of rectangular cylinders with no trailing jets where as steady state computation is performed when jet is introduced. It is found that drag can be reduced by introducing jets with small intensity in rear stagnation region of the rectangular cylinders.

Fluidic Chevrons for Jet Noise Reduction

NASA Technical Reports Server (NTRS)

Kinzie, Kevin; Henderson, Brenda; Whitmire, Julia

2004-01-01

Chevron mixing devices are used to reduce noise from commercial separate-flow turbofan engines. Mechanical chevron serrations at the nozzle trailing edge generate axial vorticity that enhances jet plume mixing and consequently reduces far-field noise. Fluidic chevrons generated with air injected near the nozzle trailing edge create a vorticity field similar to that of the mechanical chevrons and allow more flexibility in controlling acoustic and thrust performance than a passive mechanical design. In addition, the design of such a system has the future potential for actively controlling jet noise by pulsing or otherwise optimally distributing the injected air. Scale model jet noise experiments have been performed in the NASA Langley Low Speed Aeroacoustic Wind Tunnel to investigate the fluidic chevron concept. Acoustic data from different fluidic chevron designs are shown. Varying degrees of noise reduction are achieved depending on the injection pattern and injection flow conditions. CFD results were used to select design concepts that displayed axial vorticity growth similar to that associated with mechanical chevrons and qualitatively describe the air injection flow and the impact on acoustic performance.

Trailing edge cooling using angled impingement on surface enhanced with cast chevron arrangements

DOEpatents

Lee, Ching-Pang; Heneveld, Benjamin E.; Brown, Glenn E.; Klinger, Jill

2015-05-26

A gas turbine engine component, including: a pressure side (12) having an interior surface (34); a suction side (14) having an interior surface (36); a trailing edge portion (30); and a plurality of suction side and pressure side impingement orifices (24) disposed in the trailing edge portion (30). Each suction side impingement orifice is configured to direct an impingement jet (48) at an acute angle (52) onto a target area (60) that encompasses a tip (140) of a chevron (122) within a chevron arrangement (120) formed in the suction side interior surface. Each pressure side impingement orifice is configured to direct an impingement jet at an acute angle onto an elongated target area that encompasses a tip of a chevron within a chevron arrangement formed in the pressure side interior surface.

Jet-Surface Interaction Test: Flow Measurements Results

NASA Technical Reports Server (NTRS)

Brown, Cliff; Wernet, Mark

2014-01-01

Modern aircraft design often puts the engine exhaust in close proximity to the airframe surfaces. Aircraft noise prediction tools must continue to develop in order to meet the challenges these aircraft present. The Jet-Surface Interaction Tests have been conducted to provide a comprehensive quality set of experimental data suitable for development and validation of these exhaust noise prediction methods. Flow measurements have been acquired using streamwise and cross-stream particle image velocimetry (PIV) and fluctuating surface pressure data acquired using flush mounted pressure transducers near the surface trailing edge. These data combined with previously reported far-field and phased array noise measurements represent the first step toward the experimental data base. These flow data are particularly applicable to development of noise prediction methods which rely on computational fluid dynamics to uncover the flow physics. A representative sample of the large flow data set acquired is presented here to show how a surface near a jet affects the turbulent kinetic energy in the plume, the spatial relationship between the jet plume and surface needed to generate surface trailing-edge noise, and differences between heated and unheated jet flows with respect to surfaces.

Experimental study on the use of synthetic jet actuators for lift control

NASA Astrophysics Data System (ADS)

Torres, Ricardo Benjamin

An experimental study on the use of synthetic jet actuators for lift control is conducted. The synthetic jet actuator is placed on the pressure side towards the trailing edge on a NACA 65(2)-415 airfoil representative of the cross section of an Inlet Guide Vane (IGV) in an industrial gas compressor. By redirecting or vectoring the shear layer at the trailing edge, the synthetic jet actuator increases lift and decreases drag on the airfoil without a mechanical device or flap. A compressor map that defines upper and lower bounds on operating velocities and airfoil dimensions, is compared with operating conditions of the low-speed wind tunnel at San Diego State University, to match gas compressor conditions in the wind tunnel. Realistic test conditions can range from Mach=0.12 to Mach= 0.27 and an airfoil chord from c=0.1 m to c=0.3 m. Based on the operating conditions, a final airfoil model is fabricated with a chord of c=0.1m. Several synthetic jet actuator designs are considered. A initial synthetic jet is designed to house a piezoelectric element with a material frequency of 1200 hz in a cavity with a volume of 4.47 cm3, a slot width of 0.25 mm, and a slot depth of 1.5 mm. With these dimensions, the Helmholtz frequency of the design is 1800Hz. Particle Image Velocimetry (PIV) experiments show that the design has a jet with a peak centerline jet velocity of 26 m/s at 750 Hz. A modified slant face synthetic jet is designed so that the cavity fits flush within the NACA airfoil surface. The slanted synthetic jet has a cavity volume of 4.67 cm3, a slot width of 0.25 mm, and a slot depth of 3.45 mm resulting in a Helmholtz frequency of 1170 hz for this design. PIV experiments show that the jet is redirected along the slant face according to the Coanda effect. A final synthetic jet actuator is directly integrated into the trailing edge of an airfoil with a cavity volume of 4.6 cm3, a slot width of 0.2 mm, and a slot depth of 1.6 mm. The Helmholtz frequency is 1450 Hz and

Experimental studies of shock-induced particle jetting

NASA Astrophysics Data System (ADS)

Xue, Kun; Du, Kaiyuan; Shi, Xiaoliang

2018-05-01

The dispersion of particle rings or shells by a radially divergent shock front trailed by the pressurized gases takes the form of hierarchical particle jetting. Through a semi-two-dimensional configuration, we characterize the evolution of the jetting pattern using the boundary tracking technique. In contrast to the refined filamentary jetting spread induced by the dispersal of soft and ductile flour particles, the hard and brittle quartz sand particles are dispersed into a finger-like branched pattern with much fewer jets. The interplay between the primary and secondary jets suffices to reverse the flour jetting pattern, which by contrast is negligible in the quartz sand jetting. The distinct jetting patterns displayed by the flour and quartz sand particles are related with the distinguishable networks of force chains invoked in two particles which dictate the nucleation of jets.

A Design of Experiments Investigation of Offset Streams for Supersonic Jet Noise Reduction

NASA Technical Reports Server (NTRS)

Henderson, Brenda; Papamoschou, Dimitri

2014-01-01

An experimental investigation into the noise characteristics of a dual-stream jet with four airfoils inserted in the fan nozzle was conducted. The intent of the airfoils was to deflect the fan stream relative to the core stream and, therefore, impact the development of the secondary potential core and noise radiated in the peak jet-noise direction. The experiments used a full-factorial Design of Experiments (DoE) approach to identify parameters and parameter interactions impacting noise radiation at two azimuthal microphone array locations, one of which represented a sideline viewing angle. The parameters studied included airfoil angle-of-attack, airfoil azimuthal location within the fan nozzle, and airfoil axial location relative to the fan-nozzle trailing edge. Jet conditions included subsonic and supersonic fan-stream Mach numbers. Heated jets conditions were simulated with a mixture of helium and air to replicate the exhaust velocity and density of the hot jets. The introduction of the airfoils was shown to impact noise radiated at polar angles in peak-jet noise direction and to have no impact on noise radiated at small and broadside polar angles and to have no impact on broadband-shock-associated noise. The DoE analysis showed the main effects impacting noise radiation at sideline-azimuthal-viewing angles included airfoil azimuthal angle for the airfoils on the lower side of the jet near the sideline array and airfoil trailing edge distance (with airfoils located at the nozzle trailing edge produced the lowest sound pressure levels). For an array located directly beneath the jet (and on the side of the jet from which the fan stream was deflected), the main effects impacting noise radiation included airfoil angle-of-attack and airfoil azimuthal angle for the airfoils located on the observation side of the jet as well and trailing edge distance. Interaction terms between multiple configuration parameters were shown to have significant impact on the radiated

Experimental investigation of cross-over jets in a rib-roughened trailing-edge cooling channel

NASA Astrophysics Data System (ADS)

Xue, Fei

Increasing the rotor inlet temperature can dramatically increase the efficiency and power output of the gas turbine engine. However, the melting point of turbine blade material limits the realistic upper bound of the rotor inlet temperature. As a result, the development of high temperature turbine blade material and advanced turbine blade cooling technology determines the future of turbine blade engine. Adding impingement jet holes and rib turbulators in the inner cooling channel of the gas turbine blades are two effective ways to enhance the cooling effects. The purpose of this study is to figure out the influence of different combinations of jet holes and rib turbulators on the heat transfer efficiency. A tabletop scale test model is used in the study to simulate the cooling cavity of trailing edge and its feed channel in a real gas turbine blade. The Dimensional Analysis Theory is used in the study to eliminate the influence of scaling. Two different crossover slots are tested with 5 different rib arrangements, and each of the test geometries is tested for 6 jet Reynolds numbers ranging from 10,000 to 36,000. The two different crossover slots are the crossover slots with 0 and 5 degree tilt angles. The four different rib arrangements are ribs with 0 degree, 45 degree, 90 degree and 135 degree angles of attack with respect to the flow direction. Furthermore, a smooth test section (no ribs) was also tested. The steady state liquid crystal thermography is used to quantify the heat transfer performance of the target areas. The variation of Nusselt number versus Reynolds number is plotted for each of the 10 geometries. Also, the variation of Nusselt number versus Reynolds number are compared for different rib angles of attack with the same crossover slot tilt angle, and between different crossover slots tilt angles with the same rib angle. The results show that, the area-weighted average Nusselt number increases monotonically with the Reynolds number; the target

HUBBLE: ON THE ASTEROID TRAIL

NASA Technical Reports Server (NTRS)

2002-01-01

of the galaxy. The asteroid enters the image at top center and moves down toward the lower left. Large gaps in the trail occur because the telescope is orbiting the Earth and cannot continuously observe the galaxy. This asteroid has a visual magnitude of 20.8, a diameter of one mile (1.6 kilometers), and was seen at a distance of 254 million miles from Earth and 292 million miles from the sun. Credit: R. Evans and K. Stapelfeldt (Jet Propulsion Laboratory) and NASA

Jets and Water Clouds on Jupiter

NASA Astrophysics Data System (ADS)

Lian, Yuan; Showman, A. P.

2012-10-01

Ground-based and spacecraft observations show that Jupiter exhibits multiple banded zonal jet structures. These banded jets correlate with dark and bright clouds, often called "belts" and "zones". The mechanisms that produce these banded zonal jets and clouds are poorly understood. Our previous studies showed that the latent heat released by condensation of water vapor could produce equatorial superrotation along with multiple zonal jets in the mid-to-high latitudes. However, that previous work assumed complete and instant removal of condensate and therefore could not predict the cloud formation. Here we present an improved 3D Jupiter model to investigate some effects of cloud microphysics on large-scale dynamics using a closed water cycle that includes condensation, three-dimensional advection of cloud material by the large-scale circulation, evaporation and sedimentation. We use a dry convective adjustment scheme to adjust the temperature towards a dry adiabat when atmospheric columns become convectively unstable, and the tracers are mixed within the unstable layers accordingly. Other physics parameterizations included in our model are the bottom drag and internal heat flux as well as the choices of either Newtonian heating scheme or gray radiative transfer. Given the poorly understood cloud microphysics, we perform case studies by treating the particle size and condensation/evaporation time scale as free parameters. We find that, in some cases, the active water cycle can produce multiple banded jets and clouds. However, the equatorial jet is generally very weak in all the cases because of insufficient supply of eastward eddy momentum fluxes. These differences may result from differences in the overall vertical stratification, baroclinicity, and moisture distribution in our new models relative to the older ones; we expect to elucidate the dynamical mechanisms in continuing work.

Trail Transect: A Method for Documenting Trail Changes

Treesearch

R.E. Leonard; A.M. Whitney

1977-01-01

A trail transect that documents trail conditions and changes in trails has been used successfully over the past 3 years to measure soil loss, and changes in trail width and vegetation. The system also can be used to study the relationship between trail degradation and the physical characteristics of the site. Data from trail transects can be useful in determining the...

Forming a Bose-Einstein Condensate

NASA Image and Video Library

2014-09-26

This sequence of false-color images shows the formation of a Bose-Einstein condensate in the Cold Atom Laboratory prototype at NASA Jet Propulsion Laboratory as the temperature gets progressively closer to absolute zero.

Mixing and transient interface condensation of a liquid hydrogen tank

NASA Technical Reports Server (NTRS)

Lin, C. S.; Hasan, M. M.; Nyland, T. W.

1993-01-01

Experiments were conducted to investigate the effect of axial jet-induced mixing on the pressure reduction of a thermally stratified liquid hydrogen tank. The tank was nearly cylindrical, having a volume of about 0.144 cu m with 0.559 m in diameter and 0.711 m long. A mixer/pump unit, which had a jet nozzle outlet of 0.0221 m in diameter was located 0.178 m from the tank bottom and was installed inside the tank to generate the axial jet mixing and tank fluid circulation. The liquid fill and jet flow rate ranged from 42 to 85 percent (by volume) and 0.409 to 2.43 cu m/hr, respectively. Mixing tests began with the tank pressure ranging from 187.5 to 238.5 kPa at which the thermal stratification results in 4.9 to 6.2 K liquid sub cooling. The mixing time and transient vapor condensation rate at the liquid-vapor interface are determined. Two mixing time correlations, based on the thermal equilibrium and pressure equilibrium, are developed. Both mixing time correlations are expressed as functions of system and buoyancy parameters and compared well with other experimental data. The steady state condensation rate correlation of Sonin et al. based on steam-water data is modified and expressed as a function of jet subcooling. The limited liquid hydrogen data of the present study shows that the modified steady state condensation rate correlation may be used to predict the transient condensation rate in a mixing process if the instantaneous values of jet sub cooling and turbulence intensity at the interface are employed.

Effect of Liquid Surface Turbulent Motion on the Vapor Condensation in a Mixing Tank

NASA Technical Reports Server (NTRS)

Lin, C. S.; Hasan, M. M.

1991-01-01

The effect of liquid surface motion on the vapor condensation in a tank mixed by an axial turbulent jet is numerically investigated. The average value (over the interface area) of the root-mean-squared (rms) turbulent velocity at the interface is shown to be linearly increasing with decreasing liquid height and increasing jet diameter for a given tank size. The average rms turbulent velocity is incorporated in Brown et al. (1990) condensation correlation to predict the condensation of vapor on a liquid surface. The results are in good agreement with available condensation data.

Comet Wild 2 - Jet Release

NASA Technical Reports Server (NTRS)

2004-01-01

This composite image was taken by the navigation camera during the close approach phase of Stardust's Jan 2, 2004 flyby of comet Wild 2. Several large depressed regions can be seen. Comet Wild 2 is about five kilometers (3.1 miles) in diameter. To create this image, a short exposure image showing tremendous surface detail was overlain on a long exposure image taken just 10 seconds later showing jets. Together, the images show an intensely active surface, jetting dust and gas streams into space and leaving a trail millions of kilometers long.

Steam-jet Chiller for Army Field Kitchens

DTIC Science & Technology

2009-08-01

Steam-Jet Test-Loop Schematic A vacuum pump removes air from the entire system on startup, and is occasionally used to expel air during...delivered to the tube and shell condenser. The steam is condensed and drains to the vacuum sump tank. 11 Periodically, the condensate pump ... Vacuum Roughing Pump The condenser must be held at vacuum to prevent air from insulating the condenser tubes or create a back-pressure that would

Argentine ant trail pheromone disruption is mediated by trail concentration.

PubMed

Suckling, David Maxwell; Stringer, Lloyd D; Corn, Joshua E

2011-10-01

Argentine ant trail pheromone disruption, using continuous release of the trail pheromone compound (Z)-9-hexadecanal, reduces the incidence of trails and foraging rates of field populations. However, little is known about the concentrations of pheromone required for successful disruption. We hypothesized that higher pheromone quantities would be necessary to disrupt larger ant populations. To test this, we laid a 30-cm long base trail of (Z)-9-hexadecanal on a glass surface at low and high rates (1 and 100 pg/cm) (Trail 1), and laid a second, shorter trail (Trail 2, 10 cm long, located 1.5 cm upwind) near the middle of Trail 1 at six rates (1, 10, 100, 1,000, 10,000, and 100,000 pg/cm). We then recorded and digitized movements of individual ants following Trail 1, and derived a regression statistic, r (2), as an index of trail integrity, and also recorded arrival success at the other end of the trail (30 cm) near a food supply. Disruption of trails required 100 fold more pheromone upwind, independent of base-trail concentration. This implies that in the field, trail disruption is likely to be less successful against high ant-trail densities (greater concentration of trail pheromone), and more successful against newly formed or weak trails, as could be expected along invasion fronts.

Mixing and transient interface condensation of a liquid hydrogen tank

NASA Technical Reports Server (NTRS)

Lin, C. S.; Hasan, M. M.; Nyland, T. W.

1993-01-01

Experiments were conducted to investigate the effect of axial jet-induced mixing on the pressure reduction of a thermally stratified liquid hydrogen tank. The tank was nearly cylindrical, having a volume of about 0.144 cu m with 0.559 m in diameter and 0.711 m length. A mixer/pump unit, which had a jet nozzle outlet of 0.0221 m in diameter was located 0.178 m from the tank bottom and was installed inside the tank to generate the axial jet mixing and tank fluid circulation. Mixing tests began with the tank pressures at which the thermal stratification results in 4.9-6.2 K liquid subcooling. The mixing time and transient vapor condensation rate at the liquid-vapor interface are determined. Two mixing time correlations, based on the thermal equilibrium and pressure equilibrium, are developed and expressed as functions of system and buoyancy parameters. The limited liquid hydrogen data of the present study shows that the modified steady state condensation rate correlation may be used to predict the transient condensation rate in a mixing process if the instantaneous values of jet sub cooling and turbulence intensity at the interface are employed.

Comet Wild 2 - Jet Release

NASA Image and Video Library

2004-03-18

This composite image was taken by the navigation camera during the close approach phase of Stardust's Jan 2, 2004 flyby of comet Wild 2. Several large depressed regions can be seen. Comet Wild 2 is about five kilometers (3.1 miles) in diameter. To create this image, a short exposure image showing tremendous surface detail was overlain on a long exposure image taken just 10 seconds later showing jets. Together, the images show an intensely active surface, jetting dust and gas streams into space and leaving a trail millions of kilometers long. http://photojournal.jpl.nasa.gov/catalog/PIA05578

Riding a Trail of Debris

NASA Technical Reports Server (NTRS)

2005-01-01

[figure removed for brevity, see original site] Figure 1

This image taken by NASA's Spitzer Space Telescope shows the comet Encke riding along its pebbly trail of debris (long diagonal line) between the orbits of Mars and Jupiter. This material actually encircles the solar system, following the path of Encke's orbit. Twin jets of material can also be seen shooting away from the comet in the short, fan-shaped emission, spreading horizontally from the comet.

Encke, which orbits the Sun every 3.3 years, is well traveled. Having exhausted its supply of fine particles, it now leaves a long trail of larger more gravel-like debris, about one millimeter in size or greater. Every October, Earth passes through Encke's wake, resulting in the well-known Taurid meteor shower.

This image was captured by Spitzer's multiband imaging photometer when Encke was 2.6 times farther away than Earth is from the Sun. It is the best yet mid-infrared view of the comet at this great distance. The data are helping astronomers understand how rotating comets eject particles as they circle the Sun.

Exploring the TRAILs less travelled: TRAIL in cancer biology and therapy.

PubMed

von Karstedt, Silvia; Montinaro, Antonella; Walczak, Henning

2017-05-24

The discovery that the tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) can induce apoptosis of cancer cells without causing toxicity in mice has led to the in-depth study of pro-apoptotic TRAIL receptor (TRAIL-R) signalling and the development of biotherapeutic drug candidates that activate TRAIL-Rs. The outcome of clinical trials with these TRAIL-R agonists has, however, been disappointing so far. Recent evidence indicates that many cancers, in addition to being TRAIL resistant, use the endogenous TRAIL-TRAIL-R system to their own advantage. However, novel insight on two fronts - how resistance of cancer cells to TRAIL-based pro-apoptotic therapies might be overcome, and how the pro-tumorigenic effects of endogenous TRAIL might be countered - gives reasonable hope that the TRAIL system can be harnessed to treat cancer. In this Review we assess the status quo of our understanding of the biology of the TRAIL-TRAIL-R system - as well as the gaps therein - and discuss the opportunities and challenges in effectively targeting this pathway.

Sweeping Jet Optimization Studies

NASA Technical Reports Server (NTRS)

Melton, LaTunia Pack; Koklu, Mehti; Andino, Marlyn; Lin, John C.; Edelman, Louis

2016-01-01

Progress on experimental efforts to optimize sweeping jet actuators for active flow control (AFC) applications with large adverse pressure gradients is reported. Three sweeping jet actuator configurations, with the same orifice size but di?erent internal geometries, were installed on the flap shoulder of an unswept, NACA 0015 semi-span wing to investigate how the output produced by a sweeping jet interacts with the separated flow and the mechanisms by which the flow separation is controlled. For this experiment, the flow separation was generated by deflecting the wing's 30% chord trailing edge flap to produce an adverse pressure gradient. Steady and unsteady pressure data, Particle Image Velocimetry data, and force and moment data were acquired to assess the performance of the three actuator configurations. The actuator with the largest jet deflection angle, at the pressure ratios investigated, was the most efficient at controlling flow separation on the flap of the model. Oil flow visualization studies revealed that the flow field controlled by the sweeping jets was more three-dimensional than expected. The results presented also show that the actuator spacing was appropriate for the pressure ratios examined.

On Entropy Trail

NASA Astrophysics Data System (ADS)

Farokhi, Saeed; Taghavi, Ray; Keshmiri, Shawn

2015-11-01

Stealth technology is developed for military aircraft to minimize their signatures. The primary attention was focused on radar signature, followed by the thermal and noise signatures of the vehicle. For radar evasion, advanced configuration designs, extensive use of carbon composites and radar-absorbing material, are developed. On thermal signature, mainly in the infra-red (IR) bandwidth, the solution was found in blended rectangular nozzles of high aspect ratio that are shielded from ground detectors. For noise, quiet and calm jets are integrated into vehicles with low-turbulence configuration design. However, these technologies are totally incapable of detecting new generation of revolutionary aircraft. These shall use all electric, distributed, propulsion system that are thermally transparent. In addition, composite skin and non-emitting sensors onboard the aircraft will lead to low signature. However, based on the second-law of thermodynamics, there is no air vehicle that can escape from leaving an entropy trail. Entropy is thus the only inevitable signature of any system, that once measured, can detect the source. By characterizing the entropy field based on its statistical properties, the source may be recognized, akin to face recognition technology. Direct measurement of entropy is cumbersome, however as a derived property, it can be easily measured. The measurement accuracy depends on the probe design and the sensors onboard. One novel air data sensor suite is introduced with promising potential to capture the entropy trail.

Characteristics and generation of secondary jets and secondary gigantic jets

NASA Astrophysics Data System (ADS)

Lee, Li-Jou; Huang, Sung-Ming; Chou, Jung-Kung; Kuo, Cheng-Ling; Chen, Alfred B.; Su, Han-Tzong; Hsu, Rue-Rou; Frey, Harald U.; Takahashi, Yukihiro; Lee, Lou-Chuang

2012-06-01

Secondary transient luminous events (TLEs) recorded by the ISUAL-FORMOSAT2 mission can either be secondary jets or secondary gigantic jets (GJs), depending on their terminal altitudes. The secondary jets emerge from the cloud top beneath the preceding sprites and extend upward to the base of the sprites at ˜50 km. The secondary jets likely are negative electric discharges with vertically straight luminous columns, morphologically resembling the trailing jet of the type-I GJs. The number of luminous columns in a secondary jet seems to be affected by the size of the effective capacitor plate formed near the base of the preceding sprites and the charge distribution left behind by the sprite-inducing positive cloud-to-ground discharges. The secondary GJs originate from the cloud top under the shielding area of the preceding sprites, and develop upward to reach the lower ionosphere at ˜90 km. The observed morphology of the secondary GJs can either be the curvy shifted secondary GJs extending outside the region occupied by the preceding sprites or the straight pop-through secondary GJs developing through the center of the preceding circular sprites. A key factor in determining the terminal height of the secondary TLEs appears to be the local ionosphere boundary height that established by the preceding sprites. The abundance and the distribution of the negative charge in the thundercloud following the sprite-inducing positive cloud-to-ground discharges may play important role in the generation of the secondary TLEs.

Correlates of Trail Use for Recreation and Transportation on 5 Massachusetts Trails.

PubMed

Orstad, Stephanie L; McDonough, Meghan H; Klenosky, David B; Mattson, Marifran; Troped, Philip J

2016-08-01

Promoting use of community trails is a recommended strategy for increasing population levels of physical activity. Correlates of walking and cycling for recreation or transportation differ, though few studies have compared correlates of trail-based physical activity for recreation and transportation purposes. This study examined associations of demographic, social, and perceived built environmental factors with trail use for recreation and transportation and whether associations were moderated by age, gender, and prior trail use. Adults (N = 1195) using 1 of 5 trails in Massachusetts responded to an intercept survey. We used multiple linear and logistic regression models to examine associations with trail use. Respondents' mean age was 44.9 years (standard deviation = 12.5), 55.3% were female, and 82.0% were white. Age (longer-term users only), trail use with others, travel time to the trail, and trail design were significantly associated with use for recreation (P < .05). Age, gender, trail safety (longer-term users only), travel time to the trail, trail design (younger users only), and trail beauty were associated with use for transportation (P < .05). Some common correlates were found for recreational and transportation trail use, whereas some variables were uniquely associated with use for 1 purpose. Tailored strategies are suggested to promote trail use for recreation and transportation.

Elliptic jets, part 2. Dynamics of coherent structures: Pairing

NASA Technical Reports Server (NTRS)

Husain, Hyder S.; Hussain, Fazle

1992-01-01

The dynamics of the jet column mode of vortex pairing in the near field of an elliptic jet was investigated. Hot-wire measurements and flow visualization were used to examine the details of the pairing mechanism of nonplanar vortical elliptic structures and its effect on such turbulence measures as coherent velocities, incoherent turbulence intensities, incoherent and coherent Reynolds, stresses, turbulence production, and mass entrainment. It was found that pairing of elliptic vortices in the jet column does not occur uniformly around the entire perimeter, unlike in a circular jet. Merger occurs only in the initial major-axis plane. In the initial minor-axis plane, the trailing vortex rushes through the leading vortex without pairing and then breaks down violently, producing considerably greater entrainment and mixing than in circular or plane jets.

An X-ray look at the first head-trail nebula in an X-ray binary

NASA Astrophysics Data System (ADS)

Soleri, Paolo

2011-09-01

Head-tail trails are a common feature in active galactic nuclei and pulsar bow-shocks. Heinz et al. (2008) suggested that also X-ray binaries, being jet sources moving with high velocities in dense media, can leave trails of highly ionized plasma that should be detectable at radio frequencies. During bservations of faint-persistent X-ray binaries, we discovered an optical nebula around the X-ray binary SAX J1712.6-3739, consisting of a bow-shock ring-like nebula in front of the binary and two trails originating close to it. This is the first detection of such structure in a X-ray binary and it opens a new sub-field in the study of these objects. Observations with XMM-Newton and Chandra are now needed to investigate the properties of the surrounding nebula.

An X-ray look at the first head-trail nebula in an X-ray binary

NASA Astrophysics Data System (ADS)

Soleri, Paolo

2010-10-01

Head-tail trails are a common feature in active galactic nuclei and pulsar bow-shocks. Heinz et al. (2008) suggested that also X-ray binaries, being jet sources moving with high velocities in dense media, can leave trails of highly ionized plasma that should be detectable at radio frequencies. During observations of faint-persistent X-ray binaries, we discovered an optical nebula around the X-ray binary SAX J1712.6-3739, consisting of a bow-shock ring-like nebula ``in front'' of the binary and two trails originating close to it. This is the first detection of such structure in a X-ray binary and it opens a new sub-field in the study of these objects. Observations with XMM-Newton and Chandra are now needed to investigate the properties of the surrounding nebula.

Integrated coke, asphalt and jet fuel production process and apparatus

DOEpatents

Shang, Jer Y.

1991-01-01

A process and apparatus for the production of coke, asphalt and jet fuel m a feed of fossil fuels containing volatile carbon compounds therein is disclosed. The process includes the steps of pyrolyzing the feed in an entrained bed pyrolyzing means, separating the volatile pyrolysis products from the solid pyrolysis products removing at least one coke from the solid pyrolysis products, fractionating the volatile pyrolysis products to produce an overhead stream and a bottom stream which is useful as asphalt for road pavement, condensing the overhead stream to produce a condensed liquid fraction and a noncondensable, gaseous fraction, and removing water from the condensed liquid fraction to produce a jet fuel-containing product. The disclosed apparatus is useful for practicing the foregoing process. the process provides a useful method of mass producing and jet fuels from materials such as coal, oil shale and tar sands.

Performance Comparison of Sweeping/Steady Jet Actuators

NASA Astrophysics Data System (ADS)

Hirsch, Damian; Mercier, Justin; Noca, Flavio; Gharib, Morteza

2015-11-01

Flow control through the use of steady jet actuators has been used on various aircraft models since the late 1950's. However, the focus of recent studies has shifted towards the use of sweeping jets (fluidic oscillators) rather than steady jet actuators. In this work, experiments using various jet actuator designs were conducted at GALCIT's Lucas Wind Tunnel on a NACA 0012 vertical tail model similar to that of the Boeing 767 vertical stabilizer at Reynolds numbers ranging from 0.5 to 1.2 million. The rudder angle was fixed at 20 degrees. A total of 32 jet actuators were installed along the wingspan perpendicular to the trailing edge and the rudder shoulder of the vertical stabilizer. It is known that these types of flow control prevent separation. However, the goal of this work is to compare different jet designs and evaluate their performance. Parameters such as the number of actuators, their volumetric flow, and the wind tunnel speed were varied. The lift generation capabilities of steady and sweeping jet actuators were then compared. Another set of experiments was conducted to compare a new sweeping jet actuator design with one of the standard versions. Supported by Boeing.

Numerical study of the trailing vortex of a wing with wing-tip blowing

NASA Technical Reports Server (NTRS)

Lim, Hock-Bin

1994-01-01

Trailing vortices generated by lifting surfaces such as helicopter rotor blades, ship propellers, fixed wings, and canard control surfaces are known to be the source of noise, vibration, cavitation, degradation of performance, and other hazardous problems. Controlling these vortices is, therefore, of practical interest. The formation and behavior of the trailing vortices are studied in the present research. In addition, wing-tip blowing concepts employing axial blowing and spanwise blowing are studied to determine their effectiveness in controlling these vortices and their effects on the performance of the wing. The 3D, unsteady, thin-layer compressible Navier-Stokes equations are solved using a time-accurate, implicit, finite difference scheme that employs LU-ADI factorization. The wing-tip blowing is simulated using the actuator plane concept, thereby, not requiring resolution of the jet slot geometry. Furthermore, the solution blanking feature of the chimera scheme is used to simplify the parametric study procedure for the wing-tip blowing. Computed results are shown to compare favorably with experimental measurements. It is found that axial wing-tip blowing, although delaying the rolling-up of the trailing vortices and the near-field behavior of the flowfield, does not dissipate the circulation strength of the trailing vortex farther downstream. Spanwise wing-tip blowing has the effect of displacing the trailing vortices outboard and upward. The increased 'wing-span' due to the spanwise wing-tip blowing has the effect of lift augmentation on the wing and the strengthening of the trailing vortices. Secondary trailing vortices are created at high spanwise wing-tip blowing intensities.

An Empirical Jet-Surface Interaction Noise Model with Temperature and Nozzle Aspect Ratio Effects

NASA Technical Reports Server (NTRS)

Brown, Cliff

2015-01-01

An empirical model for jet-surface interaction (JSI) noise produced by a round jet near a flat plate is described and the resulting model evaluated. The model covers unheated and hot jet conditions (1 less than or equal to jet total temperature ratio less than or equal to 2.7) in the subsonic range (0.5 less than or equal to M(sub a) less than or equal to 0.9), surface lengths 0.6 less than or equal to (axial distance from jet exit to surface trailing edge (inches)/nozzle exit diameter) less than or equal to 10, and surface standoff distances (0 less than or equal to (radial distance from jet lipline to surface (inches)/axial distance from jet exit to surface trailing edge (inches)) less than or equal to 1) using only second-order polynomials to provide predictable behavior. The JSI noise model is combined with an existing jet mixing noise model to produce exhaust noise predictions. Fit quality metrics and comparisons to between the predicted and experimental data indicate that the model is suitable for many system level studies. A first-order correction to the JSI source model that accounts for the effect of nozzle aspect ratio is also explored. This correction is based on changes to the potential core length and frequency scaling associated with rectangular nozzles up to 8:1 aspect ratio. However, more work is needed to refine these findings into a formal model.

A PIV Study of Slotted Air Injection for Jet Noise Reduction

NASA Technical Reports Server (NTRS)

Henderson, Brenda S.; Wernet, Mark P.

2012-01-01

Results from acoustic and Particle Image Velocimetry (PIV) measurements are presented for single and dual-stream jets with fluidic injection on the core stream. The fluidic injection nozzles delivered air to the jet through slots on the interior of the nozzle at the nozzle trailing edge. The investigations include subsonic and supersonic jet conditions. Reductions in broadband shock noise and low frequency mixing noise were obtained with the introduction of fluidic injection on single stream jets. Fluidic injection was found to eliminate shock cells, increase jet mixing, and reduce turbulent kinetic energy levels near the end of the potential core. For dual-stream subsonic jets, the introduction of fluidic injection reduced low frequency noise in the peak jet noise direction and enhanced jet mixing. For dual-stream jets with supersonic fan streams and subsonic core streams, the introduction of fluidic injection in the core stream impacted the jet shock cell structure but had little effect on mixing between the core and fan streams.

Snails and their trails: the multiple functions of trail-following in gastropods.

PubMed

Ng, Terence P T; Saltin, Sara H; Davies, Mark S; Johannesson, Kerstin; Stafford, Richard; Williams, Gray A

2013-08-01

Snails are highly unusual among multicellular animals in that they move on a layer of costly mucus, leaving behind a trail that can be followed and utilized for various purposes by themselves or by other animals. Here we review more than 40 years of experimental and theoretical research to try to understand the ecological and evolutionary rationales for trail-following in gastropods. Data from over 30 genera are currently available, representing a broad taxonomic range living in both aquatic and terrestrial environments. The emerging picture is that the production of mucus trails, which initially was an adaptation to facilitate locomotion and/or habitat extension, has evolved to facilitate a multitude of additional functions. Trail-following supports homing behaviours, and provides simple mechanisms for self-organisation in groups of snails, promoting aggregation and thus relieving desiccation and predation pressures. In gastropods that copulate, trail-following is an important component in mate-searching, either as an alternative, or in addition to the release of water- or air-borne pheromones. In some species, this includes a capacity of males not only to identify trails of conspecifics but also to discriminate between trails laid by females and males. Notably, trail discrimination seems important as a pre-zygotic barrier to mating in some snail species. As production of a mucus trail is the most costly component of snail locomotion, it is also tempting to speculate that evolution has given rise to various ways to compensate for energy losses. Some snails, for example, increase energy intake by eating particles attached to the mucus of trails that they follow, whereas others save energy through reducing the production of their own mucus by moving over previously laid mucus trails. Trail-following to locate a prey item or a mate is also a way to save energy. While the rationale for trail-following in many cases appears clear, the basic mechanisms of trail

DIRBE Comet Trails

NASA Technical Reports Server (NTRS)

Arendt, Richard G.

2015-01-01

Re-examination of the COBE DIRBE data reveals the thermal emission of several comet dust trails.The dust trails of 1P/Halley, 169P/NEAT, and 3200 Phaethon have not been previously reported.The known trails of 2P/Encke, and 73P/Schwassmann-Wachmann 3 are also seen. The dust trails have 12 and 25 microns surface brightnesses of <0.1 and <0.15 MJy/sr, respectively, which is <1% of the zodiacal light intensity. The trails are very difficult to see in any single daily image of the sky, but are evident as rapidly moving linear features in movies of the DIRBE data. Some trails are clearest when crossing through the orbital plane of the parent comet, but others are best seen at high ecliptic latitudes as the Earth passes over or under the dust trail. All these comets have known associations with meteor showers. This re-examination also reveals one additional comet and 13 additional asteroids that had not previously been recognized in the DIRBE data.

Flow Coupling Effects in Jet-in-Crossflow Flowfields

NASA Technical Reports Server (NTRS)

Bain, D. B.; Smith, C. E.; Liscinsky, D. S.; Holdeman, J. D.

1996-01-01

The combustor designer is typically required to design liner orifices that effectively mix air jets with crossflow effluent. CFD combustor analysis is typically used in the design process; however the jets are usually assumed to enter the combustor with a uniform velocity and turbulence profile. The jet-mainstream flow coupling is usually neglected because of the computational expense. This CFD study was performed to understand the effect of jet-mainstream flow coupling, and to assess the accuracy of jet boundary conditions that are commonly used in combustor internal calculations. A case representative of a plenum-fed quick-mix section of a Rich Burn/Quick Mix/Lean Burn combustor (i.e. a jet-mainstream mass-flow ratio of about 3 and a jet-mainstream momentum-flux ratio of about 30) was investigated. This case showed that the jet velocity entering the combustor was very non-uniform, with a low normal velocity at the leading edge of the orifice and a high normal velocity at the trailing edge of the orifice. Three different combustor-only cases were analyzed with uniform inlet jet profile. None of the cases matched the plenum-fed calculations. To assess liner thickness effects, a thin-walled case was also analyzed. The CFD analysis showed the thin-walled jets had more penetration than the thick-walled jets.

Ecological assessment of the environmental impacts of the kerosene burning in jet turbines and its improvement assessment.

PubMed

Geldermann, J; Gabriel, R; Rentz, O

1999-01-01

The burning of kerosene in jet turbines is investigated for two reference flights with a Boeing 747-400 and an Airbus A320-200, representing the typical Lufthansa planes for long and middle distance. The ecological evaluation is performed by Life Cycle Assessment (LCA). Formation of condensation trails, which is a specific environmental impact caused by air traffic, has to be considered in addition to established LCA impact categories. Based on the ecological assessment, an improvement assessment is performed. Environmental performance of diesel fuel during the combustion in car engines is analysed based on available publications. The relevant parameters for the environmental impact of the combustion of diesel (aromatics content, reduction of sulphur content, the reduction of the density and raising of the cetane number) are discussed with regard to improvements of the exhaust qualities of kerosene. A reduction of the aromatics content promises to improve the emission of soot which should be further investigated.

The effect of a trail use intervention on urban trail use in Southern Nevada.

PubMed

Clark, Sheila; Bungum, Tim; Shan, Guogen; Meacham, Mindy; Coker, Lisa

2014-10-01

Communities are building or improving trail networks for biking and walking to encourage physical activity, but the relationship between trail environments and physical activity is not well understood. We examined the effect of a trail use intervention in Southern Nevada. We monitored the usage of urban trails (n=10) in Southern Nevada before, during, and after an intervention which included a marketing campaign promoting trail use and the addition of way-finding and incremental distance signage to selected trails (October 2011-October 2012). Data were collected with infrared monitors placed on the trails for three periods of 7days. We compared pre-, mid-, and post-intervention usage rates on the 6 trails where signage was added to usage rates on the 4 control trails. The groups of trails experienced different patterns of increases and decreases over the 1-year study period. Mean users per hour increased 31% for the study trails and 35% for the control trails (p<0.001), but the total increase did not vary between the groups. Trail use increased about 33% during the 1-year study period for the intervention. Adding wayfinding and incremental distance signage appeared to support the increase in usage which followed the marketing campaign. Copyright © 2014 Elsevier Inc. All rights reserved.

DRBE comet trails

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

Arendt, Richard G., E-mail: Richard.G.Arendt@nasa.gov

2014-12-01

Re-examination of the Cosmic Background Explorer Diffuse Infrared Background Experiment (DIRBE) data reveals the thermal emission of several comet dust trails. The dust trails of 1P/Halley, 169P/NEAT, and 3200 Phaethon have not been previously reported. The known trails of 2P/Encke and 73P/Schwassmann–Wachmann 3 are also seen. The dust trails have 12 and 25 μm surface brightnesses of <0.1 and <0.15 MJy sr{sup −1}, respectively, which is <1% of the zodiacal light intensity. The trails are very difficult to see in any single daily image of the sky, but are evident as rapidly moving linear features in movies of the DIRBEmore » data. Some trails are clearest when crossing through the orbital plane of the parent comet, but others are best seen at high ecliptic latitudes as the Earth passes over or under the dust trail. All these comets have known associations with meteor showers. This re-examination also reveals 1 additional comet and 13 additional asteroids that had not previously been recognized in the DIRBE data.« less

A Radio Jet Drives a Molecular and Atomic Gas Outflow in Multiple Regions within One Square Kiloparsec of the Nucleus of the nearby Galaxy IC5063

NASA Astrophysics Data System (ADS)

Dasyra, K. M.; Bostrom, A. C.; Combes, F.; Vlahakis, N.

2015-12-01

We analyzed near-infrared data of the nearby galaxy IC5063 taken with the Very Large Telescope SINFONI instrument. IC5063 is an elliptical galaxy that has a radio jet nearly aligned with the major axis of a gas disk in its center. The data reveal multiple signatures of molecular and atomic gas that has been kinematically distorted by the passage of the jet plasma or cocoon within an area of ˜1 kpc2. Concrete evidence that the interaction of the jet with the gas causes the gas to accelerate comes from the detection of outflows in four different regions along the jet trail: near the two radio lobes, between the radio emission tip and the optical narrow-line-region cone, and at a region with diffuse 17.8 GHz emission midway between the nucleus and the north radio lobe. The outflow in the latter region is biconical, centered 240 pc away from the nucleus, and oriented perpendicularly to the jet trail. The diffuse emission that is observed as a result of the gas entrainment or scattering unfolds around the trail and away from the nucleus with increasing velocity. It overall extends for ≳700 pc parallel and perpendicular to the trail. Near the outflow starting points, the gas has a velocity excess of 600-1200 km s-1 with respect to ordered motions, as seen in [Fe ii], {Pa}α , or {{{H}}}2 lines. High {{{H}}}2 (1-0) S(3)/S(1) flux ratios indicate non-thermal excitation of gas in the diffuse outflow.

On the TRAIL to successful cancer therapy? Predicting and counteracting resistance against TRAIL-based therapeutics

PubMed Central

Dimberg, Lina Y.; Anderson, Charles K.; Camidge, Ross; Behbakht, Kian; Thorburn, Andrew; Ford, Heide L.

2015-01-01

TRAIL and agonistic antibodies against TRAIL death receptors kill tumor cells while causing virtually no damage to normal cells. Several novel drugs targeting TRAIL receptors are currently in clinical trials. However, TRAIL resistance is a common obstacle in TRAIL based therapy and limits the efficiency of these drugs. In this review article we discuss different mechanisms of TRAIL resistance and how they can be predicted and therapeutically circumvented. In addition, we provide a brief overview of all TRAIL based clinical trials conducted so far. It is apparent that although the effects of TRAIL therapy are disappointingly modest overall, a small subset of patients responds very well to TRAIL. We argue that the true potential of targeting TRAIL death receptors in cancer can only be reached when we find efficient ways to select for those patients that are most likely to benefit from the treatment. To achieve this, it is crucial to identify biomarkers that can help us predict TRAIL sensitivity. PMID:22580613

Investigation of distributor vane jets to decrease the unsteady load on hydro turbine runner blades

NASA Astrophysics Data System (ADS)

Lewis, B. J.; Cimbala, J. M.; Wouden, A. M.

2012-11-01

As the runner blades of a Francis hydroturbine pass though the wakes created from the wicket gates, they experience a significant change in absolute velocity, flow angle, and pressure. The concept of adding jets to the trailing edge of the wicket gates is proposed as a method for reducing the dynamic load on the hydroturbine runner blades. Computational experiments show a decrease in velocity variation experienced by the runner blade with the addition of the jets. The decrease in velocity variation resulted in a 43% decrease in global torque variation at the runner passing frequency. However, an increased variation was observed at the wicket gate passing frequency. Also, a 5.7% increase in average global torque was observed with the addition of blowing from the trailing-edge of the wicket gates.

Low-speed wind tunnel investigation of a semispan STOL jet transport wing body with an upper surface blown jet flap

NASA Technical Reports Server (NTRS)

Phelps, A. E., III; Letko, W.; Henderson, R. L.

1973-01-01

An investigation of the static longitudinal aerodynamic characteristics of a semispan STOL jet transport wing-body with an upper-surface blown jet flap for lift augmentation was conducted in a low-speed wind tunnel having a 12-ft octagonal test section. The semispan swept wing had an aspect ratio of 3.92 (7.84 for the full span) and had two simulated turbofan engines mounted ahead of and above the wing in a siamese pod equipped with an exhaust deflector. The purpose of the deflector was to spread the engine exhaust into a jet sheet attached to the upper surface of the wing so that it would turn downward over the flap and provide lift augmentation. The wing also had optional boundary-layer control provided by air blowing through a thin slot over a full-span plain trailing-edge flap.

Dimensional Transmutation by Monopole Condensation in QCD

NASA Astrophysics Data System (ADS)

Cho, Y. M.

2015-01-01

The dimensional transmutation by the monopole condensation in QCD is reviewed. Using Abelian projection of the gauge potential which projects out the monopole potential gauge independently, we we show that there are two types of gluons: the color neutral binding gluons which plays the role of the confining agent and the colored valence gluons which become confined prisoners. With this we calculate the one-loop QCD effective potential and show the monopole condensation becomes the true vacuum of QCD. We propose to test the existence of two types of gluons experimentally by re-analyzing the existing gluon jets data.

Ohio trail users

Treesearch

Roger E. McCay

1976-01-01

Hikers, horseback riders, bicycle riders, and motorcycle riders were interviewed on randomly selected trails in Ohio to better understand who they are and why they use trails. Bicycle riders were found to be the most active trail users; bicycle and motorcycle riders were younger than hikers and horseback riders. The majority of hikers and horseback riders preferred...

Radio jet refraction in galactic atmospheres with static pressure gradients

NASA Technical Reports Server (NTRS)

Henriksen, R. N.; Vallee, J. P.; Bridle, A. H.

1981-01-01

A theory of double radio sources which have a 'Z' or 'S' morphology is proposed, based on the refraction of radio jets in the extended atmosphere of an elliptical galaxy. The model describes a collimated jet of supersonic material bending self-consistently under the influence of external static pressure gradients. Gravity and magnetic fields are neglected in the simplest case except insofar as they determine the static pressure distribution. The calculation is a straightforward extension of a method used to calculate a ram-pressure model for twin radio trails ('C' morphology). It may also be described as a continuous-jet version of a buoyancy model proposed in 1973. The model has the added virtue of invoking a galactic atmosphere similar to those already indicated by X-ray measurements of some other radio galaxies and by models for the collimation of other radio jets.

The science of trail surveys: Recreation ecology provides new tools for managing wilderness trails

USGS Publications Warehouse

Marion, Jeffrey L.; Wimpey, Jeremy F.; Park, Logan O.

2011-01-01

Recreation ecology examines the effects of recreation on protected area ecosystems. One core focus of recreation ecology research is trail science, including the development of efficient protocols to assess and monitor the type and severity of resource impacts, analyses to improve knowledge of factors that influence trail conditions, and studies to assist land managers in improving trail design, maintenance, and visitor management. This article reviews alternative trail survey methodologies most useful for the management of wilderness and backcountry trail networks. Illustrations and implications from survey data for trail planning, design, and management are included.

Investigating the Feedback Path in a Jet-Surface Resonant Interaction

NASA Technical Reports Server (NTRS)

Zaman, K. B. M. Q.; Fagan, A. F.; Bridges, J. E.; Brown, C. A.

2015-01-01

A resonant interaction between an 8:1 aspect ratio rectangular jet and flat-plates, placed parallel to the jet, is studied experimentally. For certain locations of the plate relative to the jet, the resonance takes place with a loud accompanying tone. The sound pressure level spectra are often marked by multiple peaks. The frequencies of the spectral peaks are studied as a function of the streamwise length of the plate, its relative location to the jet as well as the jet Mach number. It is demonstrated that the tones are not due to a simple feedback between the plate's trailing edge and the nozzle's exit; the leading edge of the plate also comes into play in the frequency selection. With parametric variation, it is found that there is an order in the most energetic spectral peaks; their frequencies cluster in distinct bands. The 'fundamental', i.e., the lowest frequency band is explained by an acoustic feedback involving diffraction at the plate's leading edge.

Thigmotaxis Mediates Trail Odour Disruption.

PubMed

Stringer, Lloyd D; Corn, Joshua E; Sik Roh, Hyun; Jiménez-Pérez, Alfredo; Manning, Lee-Anne M; Harper, Aimee R; Suckling, David M

2017-05-10

Disruption of foraging using oversupply of ant trail pheromones is a novel pest management application under investigation. It presents an opportunity to investigate the interaction of sensory modalities by removal of one of the modes. Superficially similar to sex pheromone-based mating disruption in moths, ant trail pheromone disruption lacks an equivalent mechanistic understanding of how the ants respond to an oversupply of their trail pheromone. Since significant compromise of one sensory modality essential for trail following (chemotaxis) has been demonstrated, we hypothesised that other sensory modalities such as thigmotaxis could act to reduce the impact on olfactory disruption of foraging behaviour. To test this, we provided a physical stimulus of thread to aid trailing by Argentine ants otherwise under disruptive pheromone concentrations. Trail following success was higher using a physical cue. While trail integrity reduced under continuous over-supply of trail pheromone delivered directly on the thread, provision of a physical cue in the form of thread slightly improved trail following and mediated trail disruption from high concentrations upwind. Our results indicate that ants are able to use physical structures to reduce but not eliminate the effects of trail pheromone disruption.

Multi-instrumental observations of a positive gigantic jet produced by a winter thunderstorm in Europe

NASA Astrophysics Data System (ADS)

van der Velde, Oscar A.; Bór, József; Li, Jingbo; Cummer, Steven A.; Arnone, Enrico; Zanotti, Ferruccio; Füllekrug, Martin; Haldoupis, Christos; Naitamor, Samir; Farges, Thomas

2010-12-01

At 2336:56 UTC on 12 December 2009, a bright gigantic jet (GJ) was recorded by an observer in Italy. Forty-nine additional sprites, elves, halos and two cases of upward lightning were observed that night. The location of the GJ corresponded to a distinct cloud top (-34°C) west of Ajaccio, Corsica. The GJ reached approximately 91 km altitude, with a "trailing jet" reaching 49-59 km, matching with earlier reported GJs. The duration was short at 120-160 ms. This is the first documented GJ which emerged from a maritime winter thunderstorm only 6.5 km tall, showing high cloud tops are not required for initiation of GJs. In the presence of strong vertical wind shear, the meteorological situation was different from typical outbreaks of fall and winter thunderstorms in the Mediterranean. During the trailing jet phase of the GJ, a sprite with halo triggered by a nearby cloud-to-ground lightning flash occurred at a relatively low altitude (<72 km). At the same time, the trailing jet and beads were reilluminated. Electromagnetic waveforms from Hungary, Poland, and the USA revealed this GJ is the first reported to transfer negative charge (approximately 136 C) from the ionosphere to the positively charged origins in the cloud (i.e., a positive cloud-to-ionosphere discharge, +CI), with a large total charge moment change of 11600 C km and a maximum current of 3.3 kA. Early VLF transmitter amplitude perturbations detected concurrently with the GJ confirm the production of large conductivity changes due to electron density enhancements in the D-region of the ionosphere.

A collision in 2009 as the origin of the debris trail of asteroid P/2010 A2.

PubMed

Snodgrass, Colin; Tubiana, Cecilia; Vincent, Jean-Baptiste; Sierks, Holger; Hviid, Stubbe; Moissl, Richard; Boehnhardt, Hermann; Barbieri, Cesare; Koschny, Detlef; Lamy, Philippe; Rickman, Hans; Rodrigo, Rafael; Carry, Benoît; Lowry, Stephen C; Laird, Ryan J M; Weissman, Paul R; Fitzsimmons, Alan; Marchi, Simone

2010-10-14

The peculiar object P/2010 A2 was discovered in January 2010 and given a cometary designation because of the presence of a trail of material, although there was no central condensation or coma. The appearance of this object, in an asteroidal orbit (small eccentricity and inclination) in the inner main asteroid belt attracted attention as a potential new member of the recently recognized class of main-belt comets. If confirmed, this new object would expand the range in heliocentric distance over which main-belt comets are found. Here we report observations of P/2010 A2 by the Rosetta spacecraft. We conclude that the trail arose from a single event, rather than a period of cometary activity, in agreement with independent results. The trail is made up of relatively large particles of millimetre to centimetre size that remain close to the parent asteroid. The shape of the trail can be explained by an initial impact ejecting large clumps of debris that disintegrated and dispersed almost immediately. We determine that this was an asteroid collision that occurred around 10 February 2009.

Targeting Death Receptor TRAIL-R2 by Chalcones for TRAIL-Induced Apoptosis in Cancer Cells

PubMed Central

Szliszka, Ewelina; Jaworska, Dagmara; Kłósek, Małgorzata; Czuba, Zenon P.; Król, Wojciech

2012-01-01

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) induces apoptosis in cancer cells without toxicity to normal cells. TRAIL binds to death receptors, TRAIL-R1 (DR4) and TRAIL-R2 (DR5) expressed on cancer cell surface and activates apoptotic pathways. Endogenous TRAIL plays an important role in immune surveillance and defense against cancer cells. However, as more tumor cells are reported to be resistant to TRAIL mediated death, it is important to search for and develop new strategies to overcome this resistance. Chalcones can sensitize cancer cells to TRAIL-induced apoptosis. We examined the cytotoxic and apoptotic effects of TRAIL in combination with four chalcones: chalcone, isobavachalcone, licochalcone A and xanthohumol on HeLa cancer cells. The cytotoxicity was measured by MTT and LDH assays. The apoptosis was detected using annexin V-FITC staining by flow cytometry and fluorescence microscopy. Death receptor expression was analyzed using flow cytometry. The decreased expression of death receptors in cancer cells may be the cause of TRAIL-resistance. Chalcones enhance TRAIL-induced apoptosis in HeLa cells through increased expression of TRAIL-R2. Our study has indicated that chalcones augment the antitumor activity of TRAIL and confirm their cancer chemopreventive properties. PMID:23203129

Computational Evaluation of the Steady and Pulsed Jet Effects on the Performance of a Circulation Control Wing Section

NASA Technical Reports Server (NTRS)

Liu, Yi; Sankar, Lakshmi N.; Englar, Robert; Ahuja, K.; Gaeta, R.

2003-01-01

Circulation Control Wing (CCW) technology is a very effective way of achieving very high lift coefficients needed by aircraft during take-off and landing. This technology can also be used to directly control the flow field over the wing. Compared to a conventional high-lift system, a Circulation Control Wing (CCW) can generate the required values of lift coefficient C(sub L,max) during take-off/landing with fewer or no moving parts and much less complexity. Earlier designs of CCW configurations used airfoils with a large radius rounded trailing edge to maximize the lift benefit. However, these designs also produced very high drag. These high drag levels associated with the blunt, large radius trailing edge can be prohibitive under cruise conditions when Circulation Control is no longer necessary. To overcome this difficulty, an advanced CCW section, i.e., a circulation hinged flap was developed to replace the original rounded trailing edge CC airfoil. This concept developed by Englar is shown. The upper surface of the CCW flap is a large-radius arc surface, but the lower surface of the flap is flat. The flap could be deflected from 0 degrees to 90 degrees. When an aircraft takes-off or lands, the flap is deflected as in a conventional high lift system. Then this large radius on the upper surface produces a large jet turning angle, leading to high lift. When the aircraft is in cruise, the flap is retracted and a conventional sharp trailing edge shape results, greatly reducing the drag. This kind of flap does have some moving elements that increase the weight and complexity over an earlier CCW design. But overall, the hinged flap design still maintains most of the Circulation Control high lift advantages, while greatly reducing the drag in cruising condition associated with the rounded trailing edge CCW design. In the present work, an unsteady three-dimensional Navier-Stokes analysis procedure has been developed and applied to this advanced CCW configuration. The

Two-dimensional model of the interaction of a plane acoustic wave with nozzle edge and wing trailing edge.

PubMed

Faranosov, Georgy A; Bychkov, Oleg P

2017-01-01

The interaction of a plane acoustic wave with two-dimensional model of nozzle edge and trailing edge is investigated theoretically by means of the Wiener-Hopf technique. The nozzle edge and the trailing edge are simulated by two half-planes with offset edges. Shear layer behind the nozzle edge is represented by a vortex sheet supporting Kelvin-Helmholtz instability waves. The considered configuration combines two well-known models (nozzle edge and trailing edge), and reveals additional interesting physical aspects. To obtain the solution, the matrix Wiener-Hopf equation is solved in conjunction with a requirement that the full Kutta condition is imposed at the edges. Factorization of the kernel matrix is performed by the combination of Padé approximation and the pole removal technique. This procedure is used to obtain numerical results. The results indicate that the diffracted acoustic field may be significantly intensified due to scattering of hydrodynamic instability waves into sound waves provided that the trailing edge is close enough to the vortex sheet. Similar mechanism may be responsible for the intensification of jet noise near a wing.

Certification trails for data structures

NASA Technical Reports Server (NTRS)

Sullivan, Gregory F.; Masson, Gerald M.

1993-01-01

Certification trails are a recently introduced and promising approach to fault detection and fault tolerance. The applicability of the certification trail technique is significantly generalized. Previously, certification trails had to be customized to each algorithm application; trails appropriate to wide classes of algorithms were developed. These certification trails are based on common data-structure operations such as those carried out using these sets of operations such as those carried out using balanced binary trees and heaps. Any algorithms using these sets of operations can therefore employ the certification trail method to achieve software fault tolerance. To exemplify the scope of the generalization of the certification trail technique provided, constructions of trails for abstract data types such as priority queues and union-find structures are given. These trails are applicable to any data-structure implementation of the abstract data type. It is also shown that these ideals lead naturally to monitors for data-structure operations.

Active Flow Control Using Sweeping Jet Actuators on a Semi-Span Wing Model

NASA Technical Reports Server (NTRS)

Melton, LaTunia Pack; Koklu, Mehti

2016-01-01

Wind tunnel experiments were performed using active flow control on an unswept semispan wing model with a 30% chord trailing edge flap to aid in the selection of actuators for a planned high Reynolds number experiment. Two sweeping jet actuator sizes were investigated to determine the influence of actuator size on the active flow control system efficiency. Sweeping jet actuators with orifice sizes of 1 mm x 2 mm and 2 mm x 4 mm were selected because of the differences in actuator jet sweep angle. The parameters that were varied include actuator momentum, freestream velocity, and trailing edge flap deflection angle. Steady and unsteady pressure data, Particle Image Velocimetry data, and force and moment data were acquired to assess the performance of the two actuators. In addition to the wind tunnel experiments, benchtop studies of the actuators were performed to characterize the jets produced by each actuator. Benchtop investigations of the smaller actuator reveal that the jet exiting the actuator has a reduced sweep angle compared to published data for larger versions of this type of actuator. The larger actuator produces an oscillating jet that attaches to the external di?user walls at low supply pressures and produces the expected sweep angles. The AFC results using the smaller actuators show that while the actuators can control flow separation, the selected spacing of 3.3 cm may be too large due to the reduced sweep angle. In comparison, the spacing for the larger actuators, 6.6 cm, appears to be optimal for the Mach numbers investigated. Particle Image Velocimetry results are presented and show how the wall jets produced by the actuators cause the flow to attach to the flap surface.

Trail pheromone disruption of Argentine ant trail formation and foraging.

PubMed

Suckling, David Maxwell; Peck, Robert W; Stringer, Lloyd D; Snook, Kirsten; Banko, Paul C

2010-01-01

Trail pheromone disruption of invasive ants is a novel tactic that builds on the development of pheromone-based pest management in other insects. Argentine ant trail pheromone, (Z)-9-hexadecenal, was formulated as a micro-encapsulated sprayable particle and applied against Argentine ant populations in 400 m2 field plots in Hawai'i Volcanoes National Park. A widely dispersed point source strategy for trail pheromone disruption was used. Traffic rates of ants in bioassays of treated filter paper, protected from rainfall and sunlight, indicated the presence of behaviorally significant quantities of pheromone being released from the formulation for up to 59 days. The proportion of plots, under trade wind conditions (2–3 m s−1), with visible trails was reduced for up to 14 days following treatment, and the number of foraging ants at randomly placed tuna-bait cards was similarly reduced. The success of these trail pheromone disruption trials in a natural ecosystem highlights the potential of this method for control of invasive ant species in this and other environments.

Trail Pheromone Disruption of Argentine Ant Trail Formation and Foraging

USGS Publications Warehouse

Suckling, D.M.; Peck, R.W.; Stringer, L.D.; Snook, K.; Banko, P.C.

2010-01-01

Trail pheromone disruption of invasive ants is a novel tactic that builds on the development of pheromone-based pest management in other insects. Argentine ant trail pheromone, (Z)-9-hexadecenal, was formulated as a micro-encapsulated sprayable particle and applied against Argentine ant populations in 400 m2 field plots in Hawai'i Volcanoes National Park. A widely dispersed point source strategy for trail pheromone disruption was used. Traffic rates of ants in bioassays of treated filter paper, protected from rainfall and sunlight, indicated the presence of behaviorally significant quantities of pheromone being released from the formulation for up to 59 days. The proportion of plots, under trade wind conditions (2-3 m s-1), with visible trails was reduced for up to 14 days following treatment, and the number of foraging ants at randomly placed tuna-bait cards was similarly reduced. The success of these trail pheromone disruption trials in a natural ecosystem highlights the potential of this method for control of invasive ant species in this and other environments. ?? Springer Science+Business Media, LLC 2010.

Maintenance of order in a moving strong condensate

NASA Astrophysics Data System (ADS)

Whitehouse, Justin; Costa, André; Blythe, Richard A.; Evans, Martin R.

2014-11-01

We investigate the conditions under which a moving condensate may exist in a driven mass transport system. Our paradigm is a minimal mass transport model in which n - 1 particles move simultaneously from a site containing n > 1 particles to the neighbouring site in a preferred direction. In the spirit of a zero-range process the rate u(n) of this move depends only on the occupation of the departure site. We study a hopping rate u(n) = 1 + b/nα numerically and find a moving strong condensate phase for b > bc(α) for all α > 0. This phase is characterised by a condensate that moves through the system and comprises a fraction of the system's mass that tends to unity. The mass lost by the condensate as it moves is constantly replenished from the trailing tail of low occupancy sites that collectively comprise a vanishing fraction of the mass. We formulate an approximate analytical treatment of the model that allows a reasonable estimate of bc(α) to be obtained. We show numerically (for α = 1) that the transition is of mixed order, exhibiting a discontinuity in the order parameter as well as a diverging length scale as b\\searrow bc .

Resonant Interaction of a Rectangular Jet with a Flat-Plate

NASA Technical Reports Server (NTRS)

Zaman, K. B. M. Q.; Fagan, A. F.; Clem, M. M.; Brown, C. A.

2014-01-01

A resonant interaction between a large aspect ratio rectangular jet and a flat-plate is addressed in this experimental study. The plate is placed parallel to but away from the direct path of the jet. At high subsonic conditions and for certain relative locations of the plate, the resonance accompanied by an audible tone is encountered. The trends of the tone frequency variation exhibit some similarities to, but also marked differences from, corresponding trends of the well-known edge-tone phenomenon. Under the resonant condition flow visualization indicates a periodic flapping motion of the jet column. Phase-averaged Mach number data obtained near the plate's trailing edge illustrate that the jet cross-section goes through large contortions within the period of the tone. Farther downstream a clear 'axis switching' takes place. These results suggest that the assumption of two-dimensionality should be viewed with caution in any analysis of the flow.

Investigating the Feedback Path in a Jet-Surface Resonant Interaction

NASA Technical Reports Server (NTRS)

Zaman, Khairul; Fagan, Amy; Bridges, James; Brown, Cliff

2015-01-01

A resonant interaction between an 8:1 aspect ratio rectangular jet and flat-plates, placed parallel to the jet, is addressed in this study. For certain relative locations of the plates, the resonance takes place with accompanying audible tones. Even when the tone is not audible the sound pressure level spectra is often marked by conspicuous peaks. The frequencies of the spectral peaks, as functions of the streamwise length of the plate and its relative location to the jet as well as the jet Mach number, are explored in an effort of understand the flow mechanism. It is demonstrated that the tones are not due to a simple feedback between the plates trailing edge and the nozzle exit; the leading edge also comes into play in determining the frequency. An acoustic feedback path, involving diffraction from the leading edge, appears to explain the frequencies of some of the spectral peaks.

Investigation of plasma-induced erosion of multilayer condenser optics

NASA Astrophysics Data System (ADS)

Anderson, Richard J.; Buchenauer, Dean A.; Williams, K. A.; Clift, W. M.; Klebanoff, L. E.; Edwards, N. V.; Wood, O. R., II; Wurm, S.

2005-05-01

Experiments are presented that investigate the mechanistic cause of multilayer erosion observed from condenser optics exposed to EUV laser-produced plasma (LPP) sources. Using a Xe filament jet source excited with Nd-YAG laser radiation (300 mJ/pulse), measurements were made of material erosion from Au, Mo, Si and C using coated quartz microbalances located 127 mm from the plasma. The observed erosion rates were as follows: Au=99nm/106 shots, Mo= 26nm/106 shots, Si=19nm/106 shots, and C=6nm/106 shots. The relative ratio Au:Mo:Si:C of erosion rates observed experimentally, 16:4:3:1 compares favorably with that predicted from an atomic sputtering model assuming 20 kV Xe ions, 16:6:4:1. The relative agreement indicates that Xe-substrate sputtering is largely responsible for the erosion of Mo/Si multilayers on condenser optics that directly face the plasma. Time-of-flight Faraday cup measurements reveal the emission of high energy Xe ions from the Xe-filament jet plasma. The erosion rate does not depend on the repetition rate of the laser, suggesting a thermal mechanism is not operative. The Xe-filament jet erosion is ~20x that observed from a Xe spray jet. Since the long-lived (millisecond time scale) plasma emanating from these two sources are the same to within ~30%, sputtering from this long-lived plasma can be ruled out as an erosion agent.

Acoustically Forced Coaxial Hydrogen/Liquid Oxygen Jet Flames

DTIC Science & Technology

2016-05-15

Briefing Charts 3. DATES COVERED (From - To) 25 April 2016 - 15 May 2016 4. TITLE AND SUBTITLE Acoustically Forced Coaxial Hydrogen / Liquid Oxygen Jet...area code) N/A Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std. 239.18 1 Acoustically Forced Coaxial Hydrogen / Liquid Oxygen Jet Flames...propellants be stored in condensed form – e.g., kerosene, liquid oxygen in rockets • Combustion systems can no longer be designed to meet modern

Happy trails: the effect of a media campaign on urban trail use in southern Nevada.

PubMed

Clark, Sheila; Bungum, Tim J; Meacham, Mindy; Coker, Lisa

2015-01-01

Many Americans do not meet recommendations for physical activity (PA). Communities are building trail networks to encourage PA, but the relationship between trails and PA is not well understood. We monitored usage of urban trails (N = 10) in Las Vegas, NV, before and after a promotional marketing campaign (October 2011 and April 2012). The media campaign featured print, online, and radio ads, as well as billboards and signage on gas pumps. Data were collected with infrared monitors that were placed on the trails for periods of 7 days. We compared preintervention and postintervention usage rates. Mean usage increased (P < .001) from 3.91 to 5.95 users per hour (52.17%) after the promotional campaign. We observed significant increases at 7 individual trails, significant declines at 2 trails, and no change at 1 trail. Promotional campaigns may be an effective way to increase trail usage and encourage PA.

Association between thyroid hormones and TRAIL.

PubMed

Bernardi, Stella; Bossi, Fleur; Toffoli, Barbara; Giudici, Fabiola; Bramante, Alessandra; Furlanis, Giulia; Stenner, Elisabetta; Secchiero, Paola; Zauli, Giorgio; Carretta, Renzo; Fabris, Bruno

2017-11-01

Recent studies suggest that a circulating protein called TRAIL (TNF-related apoptosis-inducing ligand) might have a role in the regulation of body weight and metabolism. Interestingly, thyroid hormones seem to increase TRAIL tissue expression. This study aimed at evaluating whether overt thyroid disorders affected circulating TRAIL levels. TRAIL circulating levels were measured in euthyroid, hyperthyroid, and hypothyroid patients before and after thyroid function normalization. Univariate and multivariate analyses were performed to evaluate the correlation between thyroid hormones and TRAIL. Then, the stimulatory effect of both triiodothyronine (T3) and thyroxine (T4) on TRAIL was evaluated in vitro on peripheral blood mononuclear cells. Circulating levels of TRAIL significantly increased in hyperthyroid and decreased in hypothyroid patients as compared to controls. Once thyroid function was restored, TRAIL levels normalized. There was an independent association between TRAIL and both fT3 and fT4. Consistent with these findings, T3 and T4 stimulated TRAIL release in vitro. Here we show that thyroid hormones are associated with TRAIL expression in vivo and stimulate TRAIL expression in vitro. Given the overlap between the metabolic effects of thyroid hormones and TRAIL, this work sheds light on the possibility that TRAIL might be one of the molecules mediating thyroid hormones peripheral effects. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Flaperon Modification Effect on Jet-Flap Interaction Noise Reduction for Chevron Nozzles

NASA Technical Reports Server (NTRS)

Thomas, Russell H.; Mengle, Vinod G.; Stoker, Robert W.; Brusniak, Leon; Elkoby, Ronen

2007-01-01

Jet-flap interaction (JFI) noise can become an important component of far field noise when a flap is immersed in the engine propulsive stream or is in its entrained region, as in approach conditions for under-the-wing engine configurations. We experimentally study the effect of modifying the flaperon, which is a high speed aileron between the inboard and outboard flaps, at both approach and take-off conditions using scaled models in a free jet. The flaperon modifications were of two types: sawtooth trailing edge and mini vortex generators (vg s). Parametric variations of these two concepts were tested with a round coaxial nozzle and an advanced chevron nozzle, with azimuthally varying fan chevrons, using both far field microphone arrays and phased microphone arrays for source diagnostics purposes. In general, the phased array results corroborated the far field results in the upstream quadrant pointing to JFI near the flaperon trailing edge as the origin of the far field noise changes. Specific sawtooth trailing edges in conjunction with the round nozzle gave marginal reduction in JFI noise at approach, and parallel co-rotating mini-vg s were somewhat more beneficial over a wider range of angles, but both concepts were noisier at take-off conditions. These two concepts had generally an adverse JFI effect when used in conjunction with the advanced chevron nozzle at both approach and take-off conditions.

Brownian trail rectified

NASA Astrophysics Data System (ADS)

Hurd, Alan J.; Ho, Pauline

The experiments described here indicate when one of Nature's best fractals -- the Brownian trail -- becomes nonfractal. In most ambient fluids, the trail of a Brownian particle is self-similar over many decades of length. For example, the trail of a submicron particle suspended in an ordinary liquid, recorded at equal time intervals, exhibits apparently discontinuous changes in velocity from macroscopic lengths down to molecular lengths: the trail is a random walk with no velocity memory from one step to the next. In ideal Brownian motion, the kinks in the trail persist to infinitesimal time intervals, i.e., it is a curve without tangents. Even in real Brownian motion in a liquid, the time interval must be shortened to approximately 10(-8) s before the velocity appears continuous. In sufficiently rarefied environments, this time resolution at which a Brownian trail is rectified from a curve without tangents to a smoothly varying trajectory is greatly lengthened, making it possible to study the kinetic regime by dynamic light scattering. Our recent experiments with particles in a plasma have demonstrated this capability. In this regime, the particle velocity persists over a finite step length allowing an analogy to an ideal gas with Maxwell-Boltzmann velocities; the particle mass could be obtained from equipartition. The crossover from ballistic flight to hydrodynamic diffusion was also seen.

75 FR 12254 - Official Trail Marker for the Ala Kahakai National Historic Trail

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-15

... DEPARTMENT OF THE INTERIOR National Park Service Official Trail Marker for the Ala Kahakai National Historic Trail AGENCY: National Park Service, Interior. ACTION: Official Insignia, Designation. Authority: National Trails System Act, 16 U.S.C. 1241(a) and l246(c) and Protection of Official Badges...

The Pimlico Chemistry Trail.

ERIC Educational Resources Information Center

Borrows, Peter

1984-01-01

Describes a chemistry "trail" (similar to a nature trail) which focuses on chemical phenomena in the environment. The trail includes 20 stops in and around a local school. Types of phenomena examined include building materials, air pollution, corrosion of metals, swimming pools, and others. Additional activities are also suggested. (DH)

Prognostic value of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and TRAIL receptors in renal cell cancer.

PubMed

Macher-Goeppinger, Stephan; Aulmann, Sebastian; Tagscherer, Katrin E; Wagener, Nina; Haferkamp, Axel; Penzel, Roland; Brauckhoff, Antje; Hohenfellner, Markus; Sykora, Jaromir; Walczak, Henning; Teh, Bin T; Autschbach, Frank; Herpel, Esther; Schirmacher, Peter; Roth, Wilfried

2009-01-15

The death ligand tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and its receptors (TRAIL-R) are involved in immune surveillance and tumor development. Here, we studied a possible association between the expression of TRAIL/TRAIL-Rs and the prognosis in patients with renal cell carcinomas (RCC). A tissue microarray containing RCC tumor tissue samples and corresponding normal tissue samples from 838 patients was generated. Expression of TRAIL and TRAIL-Rs was examined by immunohistochemistry and the effect of TRAIL and TRAIL-R expression on disease-specific survival was assessed. High TRAIL-R2 expression levels were associated with high-grade RCCs (P < 0.001) and correlated negatively with disease-specific survival (P = 0.01). Similarly, high TRAIL expression was associated with a shorter disease-specific survival (P = 0.01). In contrast, low TRAIL-R4 expression was associated with high-stage RCCs (P < 0.001) as well as with the incidence of distant metastasis (P = 0.03) and correlated negatively with disease-specific survival (P = 0.02). In patients without distant metastasis, multivariate Cox regression analyses revealed that TRAIL-R2 and TRAIL are independent prognostic factors for cancer-specific survival (in addition to tumor extent, regional lymph node metastasis, grade of malignancy, and type of surgery). High TRAIL-R2, high TRAIL, and low TRAIL-R4 expression levels are associated with a worse disease-specific survival in patients with RCCs. Therefore, the assessment of TRAIL/TRAIL-R expression offers valuable prognostic information that could be used to select patients for adjuvant therapy studies. Moreover, our findings are of relevance for a potential experimental therapeutic administration of TRAIL-R agonists in patients with RCCs.

Hikers and other trail users

Treesearch

Robert C. Lucas

1971-01-01

Trail users seem neglected. Trail systems are limited, largely relics of fire control rather than designed for recreation; and total trail miles are probably declining. On the other hand, participation in various kinds of trail-oriented recreation is substantial and growing. Most activity is for short periods of time close to participants' homes. A varied and...

Compatibility of Ohio trail users

Treesearch

Roger E. McCay; George H. Moeller

1976-01-01

Compatibility indexes show how Ohio trail users feel about meeting each other on the trail. All four of the major types of trail users-hikers, horseback riders, bicycle riders, and motorcycle riders-enjoy meeting their own kind. But they also feel antagonism toward the faster, more mechanized trail users; e.g., everyone likes hikers, but few like motorcycle riders....

National recreation trails: an overview

Treesearch

Joanne F. Tynon; James A. Harding; Deborah J. Chavez

1998-01-01

Since the establishment of the National Trails System in 1968, 822 trails have been designated as National Recreation Trails (NRT). These trails support a wide range of activities, including but not limited to hiking, mountain biking, cross country skiing and horseback riding. In short, NRTs can be found across a diversity of geographic settings and are frequent...

Trails and physical activity: a review.

PubMed

Starnes, Heather A; Troped, Philip J; Klenosky, David B; Doehring, Angela M

2011-11-01

To provide a synthesis of research on trails and physical activity from the public health, leisure sciences, urban planning, and transportation literatures. A search of databases was conducted to identify studies published between 1980 and 2008. 52 studies were identified. The majority were cross-sectional (92%) and published after 1999 (77%). The evidence for the effects of trails on physical activity was mixed among 3 intervention and 5 correlational studies. Correlates of trail use were examined in 13 studies. Several demographic (eg, race, education, income) and environmental factors (eg, land-use mix and distance to trail) were related to trail use. Evidence from 31 descriptive studies identified several facilitators and barriers to trail use. Economic studies (n = 5) examining trails in terms of health or recreational outcomes found trails are cost-effective and produce significant economic benefits. There is a growing body of evidence demonstrating important factors that should be considered in promoting trail use, yet the evidence for positive effects of trails on physical activity is limited. Further research is needed to evaluate the effects of trails on physical activity. In addition, trail studies that include children and youth, older adults, and racial and ethnic minorities are a research priority.

Buoyancy effects on the vapor condensation rate on a horizontal liquid surface

NASA Technical Reports Server (NTRS)

Hasan, Mohammad M.; Lin, Chin-Shun

1989-01-01

The results are presented of a numerical study of the effects of buoyancy on the direct condensation of saturated or nearly saturated vapor on a horizontal liquid surface in a cylindrical tank. The liquid motion beneath the liquid-vapor interface is induced by an axisymmetric laminar jet of subcooled liquid. Analysis and numerical results show that the dominant parameter which determines the influence of buoyancy on the condensation rate is the Richardson number. However, the effect of buoyancy on the condensation rate cannot be quantified in terms of the Richardson number alone. The critical value of the Richardson number below which the condensation rate is not significantly reduced depends on the Reynolds number as well as the Prandtl number.

TRAIL-coated lipid-nanoparticles overcome resistance to soluble recombinant TRAIL in non-small cell lung cancer cells

NASA Astrophysics Data System (ADS)

De Miguel, Diego; Gallego-Lleyda, Ana; María Ayuso, José; Erviti-Ardanaz, Sandra; Pazo-Cid, Roberto; del Agua, Celia; José Fernández, Luis; Ochoa, Ignacio; Anel, Alberto; Martinez-Lostao, Luis

2016-05-01

Purpose. Non-small cell lung cancer (NSCLC) is one the types of cancer with higher prevalence and mortality. Apo2-Ligand/TRAIL is a TNF family member able to induce apoptosis in tumor cells but not in normal cells. It has been tested in clinical trials against different types of human cancer including NSCLC. However, results of clinical trials have shown a limited efficacy of TRAIL-based therapies. Recently we have demonstrated that artificial lipid nanoparticles coated with bioactive Apo2L/TRAIL (LUV-TRAIL) greatly improved TRAIL cytotoxic ability being capable of killing chemoresistant hematological cancer cells. In the present work we have extended the study to NSCLC. Methods/patients. LUV-TRAIL-induced cytotoxicity was assessed on different NSCLC cell lines with different sensitivity to soluble TRAIL and on primary human tumor cells from three patients suffering from NSCLC cancer. We also tested LUV-TRAIL-cytotoxic ability in combination with several anti-tumor agents. Results. LUV-TRAIL exhibited a greater cytotoxic effect compared to soluble TRAIL both in A549 cells and primary human NSCLC cells. LUV-TRAIL-induced cell death was dependent on caspase-8 and caspase-3 activation. Moreover, combination of LUV-TRAIL with other anti-tumor agents such as flavopiridol, and SNS-032 clearly enhanced LUV-TRAIL-induced cytotoxicity against NSCLC cancer cells. Conclusion. The novel formulation of TRAIL based on displaying it on the surface of lipid nanoparticles greatly increases its anti-tumor activity and has clinical potential in cancer treatment.

TRAIL-coated lipid-nanoparticles overcome resistance to soluble recombinant TRAIL in non-small cell lung cancer cells.

PubMed

De Miguel, Diego; Gallego-Lleyda, Ana; Ayuso, José María; Erviti-Ardanaz, Sandra; Pazo-Cid, Roberto; del Agua, Celia; Fernández, Luis José; Ochoa, Ignacio; Anel, Alberto; Martinez-Lostao, Luis

2016-05-06

Non-small cell lung cancer (NSCLC) is one the types of cancer with higher prevalence and mortality. Apo2-Ligand/TRAIL is a TNF family member able to induce apoptosis in tumor cells but not in normal cells. It has been tested in clinical trials against different types of human cancer including NSCLC. However, results of clinical trials have shown a limited efficacy of TRAIL-based therapies. Recently we have demonstrated that artificial lipid nanoparticles coated with bioactive Apo2L/TRAIL (LUV-TRAIL) greatly improved TRAIL cytotoxic ability being capable of killing chemoresistant hematological cancer cells. In the present work we have extended the study to NSCLC. LUV-TRAIL-induced cytotoxicity was assessed on different NSCLC cell lines with different sensitivity to soluble TRAIL and on primary human tumor cells from three patients suffering from NSCLC cancer. We also tested LUV-TRAIL-cytotoxic ability in combination with several anti-tumor agents. LUV-TRAIL exhibited a greater cytotoxic effect compared to soluble TRAIL both in A549 cells and primary human NSCLC cells. LUV-TRAIL-induced cell death was dependent on caspase-8 and caspase-3 activation. Moreover, combination of LUV-TRAIL with other anti-tumor agents such as flavopiridol, and SNS-032 clearly enhanced LUV-TRAIL-induced cytotoxicity against NSCLC cancer cells. The novel formulation of TRAIL based on displaying it on the surface of lipid nanoparticles greatly increases its anti-tumor activity and has clinical potential in cancer treatment.

Novel TRAIL sensitizer Taraxacum officinale F.H. Wigg enhances TRAIL-induced apoptosis in Huh7 cells.

PubMed

Yoon, Ji-Yong; Cho, Hyun-Soo; Lee, Jeong-Ju; Lee, Hyo-Jung; Jun, Soo Young; Lee, Jae-Hye; Song, Hyuk-Hwan; Choi, SangHo; Saloura, Vassiliki; Park, Choon Gil; Kim, Cheol-Hee; Kim, Nam-Soon

2016-04-01

TRAIL (TNF-related apoptosis inducing ligand) is a promising anti-cancer drug target that selectively induces apoptosis in cancer cells. However, many cancer cells are resistant to TRAIL-induced apoptosis. Therefore, reversing TRAIL resistance is an important step for the development of effective TRAIL-based anti-cancer therapies. We previously reported that knockdown of the TOR signaling pathway regulator-like (TIPRL) protein caused TRAIL-induced apoptosis by activation of the MKK7-c-Jun N-terminal Kinase (JNK) pathway through disruption of the MKK7-TIPRL interaction. Here, we identified Taraxacum officinale F.H. Wigg (TO) as a novel TRAIL sensitizer from a set of 500 natural products using an ELISA system and validated its activity by GST pull-down analysis. Furthermore, combination treatment of Huh7 cells with TRAIL and TO resulted in TRAIL-induced apoptosis mediated through inhibition of the MKK7-TIPRL interaction and subsequent activation of MKK7-JNK phosphorylation. Interestingly, HPLC analysis identified chicoric acid as a major component of the TO extract, and combination treatment with chicoric acid and TRAIL induced TRAIL-induced cell apoptosis via JNK activation due to inhibition of the MKK7-TIPRL interaction. Our results suggest that TO plays an important role in TRAIL-induced apoptosis, and further functional studies are warranted to confirm the importance of TO as a novel TRAIL sensitizer for cancer therapy. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

Trail impacts and trail impact management related to ecotourism visitation at Torres del Paine National Park, Chile

USGS Publications Warehouse

Farrell, T.A.; Marion, J.L.

2002-01-01

Ecotourism and protected area visitation in Central and South America are largely dependent upon a relatively undisturbed quality of natural resources. However, visitation may impact vegetation, soil, water and wildlife resources, and degrade visitor facilities such as recreation sites and trails. Findings are reported from trail impact research conducted at Torres del Paine National Park in Patagonia, Chile. The frequency and magnitude of selected trail impacts and the relative effect of the amount of use, vegetation type, trail position and trail grade are investigated. Findings differed from previous studies in that amount of use was significantly related to both trail width increases and trail erosion. Management actions to minimize trail impacts are offered.

75 FR 37463 - Official Trail Marker for the Star-Spangled Banner National Historic Trail

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-29

... DEPARTMENT OF THE INTERIOR National Park Service Official Trail Marker for the Star-Spangled Banner National Historic Trail AGENCY: National Parks Service, Interior. ACTION: Official Insignia, Designation. Authority: National Trails System Act, 16 U.S.C. 124(a) and 1246(c) and Protection of Official...

The Biology of TRAIL and the Role of TRAIL-Based Therapeutics in Infectious Diseases

PubMed Central

Shepard, Brett D.; Badley, Andrew D.

2011-01-01

TNF-related apoptosis inducing ligand (TRAIL) is a key mediator of the innate immune response to infection. While TRAIL-mediated apoptosis plays an essential role in the clearance of virus-infected cells, its physiologic role also includes immunosurveilance for cancer cells. Therapeutics that induce TRAIL-mediated apoptosis in cancer cells remain a focus of ongoing investigation in clinical trials, and much has been learned from these studies regarding the efficacy and toxicity of these interventions. These data, combined with data from numerous preclinical studies that detail the important and multifaceted role of TRAIL during infection with human immunodeficiency virus and other viruses, suggest that therapeutic exploitation of TRAIL signaling offers a novel and efficacious strategy for the management of infectious diseases. PMID:21857885

Lipid Nanoparticles Decorated with TNF-Related Aptosis-Inducing Ligand (TRAIL) Are More Cytotoxic than Soluble Recombinant TRAIL in Sarcoma.

PubMed

Gallego-Lleyda, Ana; De Miguel, Diego; Anel, Alberto; Martinez-Lostao, Luis

2018-05-13

Sarcomas are rare and heterogeneous cancers classically associated with a poor outcome. Sarcomas are 1% of the cancer but recent estimations indicate that sarcomas account for 2% of the estimated cancer-related deaths. Traditional treatment with surgery, radiotherapy, and chemotherapy has improved the outcome for some types of sarcomas. However, novel therapeutic strategies to treat sarcomas are necessary. TNF-related apoptosis-inducing ligand (TRAIL) is a death ligand initially described as capable of inducing apoptosis on tumor cell while sparing normal cells. Only few clinical trials have used TRAIL-based treatments in sarcoma, but they show only low or moderate efficacy of TRAIL. Consequently, novel TRAIL formulations with an improved TRAIL bioactivity are necessary. Our group has developed a novel TRAIL formulation based on tethering this death ligand on a lipid nanoparticle surface (LUV-TRAIL) resembling the physiological secretion of TRAIL as a trasmembrane protein inserted into the membrane of exosomes. We have already demonstrated that LUV-TRAIL shows an improved cytotoxic activity when compared to soluble recombinant TRAIL both in hematological malignancies and epithelial-derived cancers. In the present study, we have tested LUV-TRAIL in several human sarcoma tumor cell lines with different sensitivity to soluble recombinant TRAIL, finding that LUV-TRAIL was more efficient than soluble recombinant TRAIL. Moreover, combined treatment of LUV-TRAIL with distinct drugs proved to be especially effective, sensitizing even more resistant cell lines to TRAIL.

Global Variation of Meteor Trail Plasma Turbulence

NASA Technical Reports Server (NTRS)

Dyrud, L. P.; Hinrichs, J.; Urbina, J.

2011-01-01

We present the first global simulations on the occurrence of meteor trail plasma irregularities. These results seek to answer the following questions: when a meteoroid disintegrates in the atmosphere will the resulting trail become plasma turbulent, what are the factors influencing the development of turbulence, and how do they vary on a global scale. Understanding meteor trail plasma turbulence is important because turbulent meteor trails are visible as non-specular trails to coherent radars, and turbulence influences the evolution of specular radar meteor trails, particularly regarding the inference of mesospheric temperatures from trail diffusion rates, and their usage for meteor burst communication. We provide evidence of the significant effect that neutral atmospheric winds and density, and ionospheric plasma density have on the variability of meteor trail evolution and the observation of nonspecular meteor trails, and demonstrate that trails are far less likely to become and remain turbulent in daylight, explaining several observational trends using non-specular and specular meteor trails.

An experimental study of the noise generating mechanisms in supersonic jets

NASA Technical Reports Server (NTRS)

Mclaughlin, D. K.

1979-01-01

Flow fluctuation measurements with normal and X-wire hot-wire probes and acoustic measurements with a traversing condenser microphone were carried out in small air jets in the Mach number range from M = 0.9 to 2.5. One of the most successful studies involved a moderate Reynolds number M = 2.1 jet. The large scale turbulence properties in the jet, and the noise radiation were characterized. A parallel study involved similar measurements on a low Reynolds number M = 0.9 jet. These measurements show that there are important differences in the noise generation process of the M = 0.9 jet in comparison with low supersonic Mach number (M = 1.4) jets. Problems encounted while performing X-wire measurements in low Reynolds number jets of M = 2.1 and 2.5, and in installing a vacuum pump are discussed.

Earth Observations taken during Expedition Four

NASA Image and Video Library

2002-05-15

ISS004-E-11807 (15 May 2002) --- This digital photograph, taken through the windows of the International Space Station on May 15, 2002, shows condensation trails over the Rhône Valley in the region west of Lyon, France. Condensation trails-or contrails-are straight lines of ice crystals that form in the wake of jet liners where air temperatures are lower than about -40 degrees Centigrade. Scientists have observed that newer contrails are thin whereas older trails have widened with time as a result of light winds. Because of this tendency for thin contrails to cover greater areas with time, it is estimated that these “artificial clouds” cover 0.1 per cent of the planet’s surface. Percentages are far higher in some places, say the scientists, such as southern California, the Ohio River Valley and parts of Europe, as illustrated here. The climatic impact of such clouds is poorly understood, which is why scientists continue to study them using images such as this.

Modified Design of Hydroturbine Wicket Gates to Include Liquid Control Jets

NASA Astrophysics Data System (ADS)

Lewis, Bryan; Cimbala, John; Wouden, Alex

2013-11-01

With the ever-increasing penetration of alternative electricity generation, it is becoming more common to operate hydroturbines under off-design conditions in order to maintain stability in the electric power grid. Improving the off-design performance of these turbines is therefore of significant importance. As the runner blades of a Francis hydroturbine pass though the wakes created by the upstream guide vanes (wicket gates and stay vanes), they experience significant changes in the instantaneous values of absolute velocity, flow angle, and pressure. The concept of adding water jets to the trailing edge of the guide vanes is proposed as a method for reducing the dynamic load on the hydroturbine runner blades, as well as modifying the flow angle of the water entering the runner to improve turbine efficiency during off-design operation. In order to add water jets that are capable of turning the flow, a modified beveled trailing edge design is presented. Computational experiments show that a +/-5° change in swirl angle is achievable with the new design, as well as up to 4% improvement in turbine efficiency during off-design operation. This correlates to an overall improvement in machine efficiency of up to 2%, when the losses through the jet channels are taken into account. Funding for this work was provided by the DOD, through the National Defense Science and Engineering Graduate (NDSEG) Fellowship, and the DOE, through the Penn State Hydropower Research Grant.

Inhibition of TRAIL-induced apoptosis and forced internalization of TRAIL receptor 1 by adenovirus proteins.

PubMed

Tollefson, A E; Toth, K; Doronin, K; Kuppuswamy, M; Doronina, O A; Lichtenstein, D L; Hermiston, T W; Smith, C A; Wold, W S

2001-10-01

Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) induces apoptosis through two receptors, TRAIL-R1 (also known as death receptor 4) and TRAIL-R2 (also known as death receptor 5), that are members of the TNF receptor superfamily of death domain-containing receptors. We show that human adenovirus type 5 encodes three proteins, named RID (previously named E3-10.4K/14.5K), E3-14.7K, and E1B-19K, that independently inhibit TRAIL-induced apoptosis of infected human cells. This conclusion was derived from studies using wild-type adenovirus, adenovirus replication-competent mutants that lack one or more of the RID, E3-14.7K, and E1B-19K genes, and adenovirus E1-minus replication-defective vectors that express all E3 genes, RID plus E3-14.7K only, RID only, or E3-14.7K only. RID inhibits TRAIL-induced apoptosis when cells are sensitized to TRAIL either by adenovirus infection or treatment with cycloheximide. RID induces the internalization of TRAIL-R1 from the cell surface, as shown by flow cytometry and indirect immunofluorescence for TRAIL-R1. TRAIL-R1 was internalized in distinct vesicles which are very likely to be endosomes and lysosomes. TRAIL-R1 is degraded, as indicated by the disappearance of the TRAIL-R1 immunofluorescence signal. Degradation was inhibited by bafilomycin A1, a drug that prevents acidification of vesicles and the sorting of receptors from late endosomes to lysosomes, implying that degradation occurs in lysosomes. RID was also shown previously to internalize and degrade another death domain receptor, Fas, and to prevent apoptosis through Fas and the TNF receptor. RID was shown previously to force the internalization and degradation of the epidermal growth factor receptor. E1B-19K was shown previously to block apoptosis through Fas, and both E1B-19K and E3-14.7K were found to prevent apoptosis through the TNF receptor. These findings suggest that the receptors for TRAIL, Fas ligand, and TNF play a role in limiting virus

Inhibition of TRAIL-Induced Apoptosis and Forced Internalization of TRAIL Receptor 1 by Adenovirus Proteins

PubMed Central

Tollefson, Ann E.; Toth, Karoly; Doronin, Konstantin; Kuppuswamy, Mohan; Doronina, Oksana A.; Lichtenstein, Drew L.; Hermiston, Terry W.; Smith, Craig A.; Wold, William S. M.

2001-01-01

Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) induces apoptosis through two receptors, TRAIL-R1 (also known as death receptor 4) and TRAIL-R2 (also known as death receptor 5), that are members of the TNF receptor superfamily of death domain-containing receptors. We show that human adenovirus type 5 encodes three proteins, named RID (previously named E3-10.4K/14.5K), E3-14.7K, and E1B-19K, that independently inhibit TRAIL-induced apoptosis of infected human cells. This conclusion was derived from studies using wild-type adenovirus, adenovirus replication-competent mutants that lack one or more of the RID, E3-14.7K, and E1B-19K genes, and adenovirus E1-minus replication-defective vectors that express all E3 genes, RID plus E3-14.7K only, RID only, or E3-14.7K only. RID inhibits TRAIL-induced apoptosis when cells are sensitized to TRAIL either by adenovirus infection or treatment with cycloheximide. RID induces the internalization of TRAIL-R1 from the cell surface, as shown by flow cytometry and indirect immunofluorescence for TRAIL-R1. TRAIL-R1 was internalized in distinct vesicles which are very likely to be endosomes and lysosomes. TRAIL-R1 is degraded, as indicated by the disappearance of the TRAIL-R1 immunofluorescence signal. Degradation was inhibited by bafilomycin A1, a drug that prevents acidification of vesicles and the sorting of receptors from late endosomes to lysosomes, implying that degradation occurs in lysosomes. RID was also shown previously to internalize and degrade another death domain receptor, Fas, and to prevent apoptosis through Fas and the TNF receptor. RID was shown previously to force the internalization and degradation of the epidermal growth factor receptor. E1B-19K was shown previously to block apoptosis through Fas, and both E1B-19K and E3-14.7K were found to prevent apoptosis through the TNF receptor. These findings suggest that the receptors for TRAIL, Fas ligand, and TNF play a role in limiting virus

A study of flow past an airfoil with a jet issuing from its lower surface

NASA Technical Reports Server (NTRS)

Krothapalli, A.; Leopold, D.

1984-01-01

The aerodynamics of a NACA 0018 airfoil with a rectangular jet of finite aspect ratio exiting from its lower surface at 90 deg to the chord were investigated. The jet was located at 50% of the wing chord. Measurements include static pressures on the airfoil surface, total pressures in the near wake, and local velocity vectors in different planes of the wake. The effects of jet cross flow interaction on the aerodynamics of the airfoil are studied. It is indicated that at all values of momentum coefficients, the jet cross flow interaction produces a strong contra-rotating vortex structure in the near wake. The flow behind the jet forms a closed recirculation region which extends up to a chord length down stream of the trailing edge which results in the flow field to become highly three dimensional. The various aerodynamic force coefficients vary significantly along the span of the wing. The results are compared with a jet flap configuration.

Acoustically-Enhanced Direct Contact Vapor Bubble Condensation

NASA Astrophysics Data System (ADS)

Boziuk, Thomas; Smith, Marc; Glezer, Ari

2017-11-01

Rate-limited, direct contact vapor condensation of vapor bubbles that are formed by direct steam injection through a nozzle in a quiescent subcooled liquid bath is accelerated using ultrasonic (MHz-range) actuation. A submerged, low power actuator produces an acoustic beam whose radiation pressure deforms the liquid-vapor interface, leading to the formation of a liquid spear that penetrates the vapor bubble to form a vapor torus with a significantly larger surface area and condensation rate. Ultrasonic focusing along the spear leads to the ejection of small, subcooled droplets through the vapor volume that impact the vapor-liquid interface and further enhance the condensation. High-speed Schlieren imaging of the formation and collapse of the vapor bubbles in the absence and presence of actuation shows that the impulse associated with the collapse of the toroidal volume leads to the formation of a turbulent vortex ring in the liquid phase. Liquid motions near the condensing vapor volume are investigated in the absence and presence of acoustic actuation using high-magnification PIV and show the evolution of a liquid jet through the center of the condensing toroidal volume and the formation and advection of vortex ring structures whose impulse appear to increase with temperature difference between the liquid and vapor phases. High-speed image processing is used to assess the effect of the actuation on the temporal and spatial variations in the characteristic scales and condensation rates of the vapor bubbles.

75 FR 37462 - Official Trail Marker for the Captain John Smith Chesapeake National Historic Trail

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-29

... DEPARTMENT OF THE INTERIOR National Park Service Official Trail Marker for the Captain John Smith Chesapeake National Historic Trail AGENCY: National Parks Service, Interior. ACTION: Official Insignia, Designation. Authority: National Trails System Act, 16 U.S.C. 124(a) and 1246(c) and Protection of Official...

Trail deterioration as an indicator of trail use in an urban forest recreation area

Treesearch

Thomas A. More

1980-01-01

The average width of a trail was used to predict trail use in an urban forest recreation area. Results show that width indicates use only very generally at best. Consequently, simply inspecting the physical condition of a trail may lead to erroneous conclusions about its use. Managers requiring more than a simple light use/heavy use classification should adopt more...

Solar-thermal jet pumping for irrigation

NASA Astrophysics Data System (ADS)

Clements, L. D.; Dellenback, P. A.; Bell, C. A.

1980-01-01

This paper describes a novel concept in solar powered irrigation pumping, gives measured performance data for the pump unit, and projected system performance. The solar-thermal jet pumping concept is centered around a conventional jet eductor pump which is commercially available at low cost. The jet eductor pump is powered by moderate temperature, moderate pressure Refrigerant-113 vapor supplied by a concentrating solar collector field. The R-113 vapor is direct condensed by the produced water and the two fluids are separated at the surface. The water goes on to use and the R-113 is repressurized and returned to the solar field. The key issue in the solar-thermal jet eductor concept is the efficiency of pump operation. Performance data from a small scale experimental unit which utilizes an electrically heated boiler in place of the solar field is presented. The solar-thermal jet eductor concept is compared with other solar irrigation concepts and optimal application situations are identified. Though having lower efficiencies than existing Rankine cycle solar-thermal irrigation systems, the mechanical and operational simplicity of this concept make it competitive with other solar powered irrigation schemes.

Surface layer motion in planetary atmosphere containing fog of condensed gases

NASA Astrophysics Data System (ADS)

Datsenko, E. N.; Vasiliev, N. I.; Orlova, I. O.; Avakimyan, N. N.

2017-11-01

The article contains a simplified model of a wave motion of the atmospheric surface of planets containing finely dispersed particles of condensed gases, it is assumed that the surface of planets is heated above the saturation temperature of gas condensate, and the surface layers of the foggy atmosphere are strongly cooled. The mechanism of formation and growth of such waves is proposed and justified. It was found that the existence of growing waves on the surface of such an atmosphere is possible, as well as, in the course of time, the formation of a vortex in the atmosphere around the planet. Perturbations of the atmosphere thickness lead to the formation of gravitational waves propagating along its surface. The thickness of the atmosphere at the crest of the wave is greater than that in the trough. While the temperature of the atmosphere under the ridge increases, it decreases under the trough due to shielding of the thermal radiation of the planet. When the crest of a gravitational wave moves, the atmosphere under the trailing edge of the crest has a temperature higher than that under the front edge, since the trailing edge of the crest is heated more intensively by radiation from the surface of the planet. The partial pressure of the vapor of the condensed gases at the rear edge of the ridge is higher than that at the front edge; the work of the pressure difference during the motion of the ridge increases its energy and height. The authors demonstrate the analogy between the mechanisms of wave growth in a foggy atmosphere of planets and the mechanism of wave growth in a thin vapor layer between a strongly heated solid surface or a metal melt and a volatile liquid.

Awareness and use of community walking trails.

PubMed

Reed, Julian A; Ainsworth, Barbara E; Wilson, Dawn K; Mixon, Gary; Cook, Annette

2004-11-01

Community trail development is an emerging strategy to increase physical activity (PA) among community residents. The purpose of this study was to assess awareness and use of trails and compare perceptions to objective data. A telephone survey was administered to a stratified sample of adults (N = 1,112) in a southeastern county in the United States. Respondents' home addresses and the locations of trails were entered into a GIS database. A kappa statistic was used to measure agreement between awareness and presence of trails. Differences in reported trail use patterns by sex, race, education, and PA levels were evaluated. There was no agreement between the awareness and presence of trails (kappa = 0.07). Fifty-six percent of the respondents reported having trails; however, only 33% reported using the trails. Of the trail users, 42% reported being regularly active in moderate-to-vigorous PA (30+ min/day for 5+ days/week), and 51% reported being less active (P < 0.003). Among walkers (> or =30 min/day for > or =5 days/week), 49% of regular walkers and 35% of irregular walkers (< walkers) reported using the trails (P < 0.04). Awareness of existing trails in this community and levels of use were low. Marketing programs should promote awareness and use of trails among older adults and irregularly active adults.

Highly selective condensation of biomass-derived methyl ketones as a source of aviation fuel.

PubMed

Sacia, Eric R; Balakrishnan, Madhesan; Deaner, Matthew H; Goulas, Konstantinos A; Toste, F Dean; Bell, Alexis T

2015-05-22

Aviation fuel (i.e., jet fuel) requires a mixture of C9 -C16 hydrocarbons having both a high energy density and a low freezing point. While jet fuel is currently produced from petroleum, increasing concern with the release of CO2 into the atmosphere from the combustion of petroleum-based fuels has led to policy changes mandating the inclusion of biomass-based fuels into the fuel pool. Here we report a novel way to produce a mixture of branched cyclohexane derivatives in very high yield (>94 %) that match or exceed many required properties of jet fuel. As starting materials, we use a mixture of n-alkyl methyl ketones and their derivatives obtained from biomass. These synthons are condensed into trimers via base-catalyzed aldol condensation and Michael addition. Hydrodeoxygenation of these products yields mixtures of C12 -C21 branched, cyclic alkanes. Using models for predicting the carbon number distribution obtained from a mixture of n-alkyl methyl ketones and for predicting the boiling point distribution of the final mixture of cyclic alkanes, we show that it is possible to define the mixture of synthons that will closely reproduce the distillation curve of traditional jet fuel. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

High-order TRAIL oligomer formation in TRAIL-coated lipid nanoparticles enhances DR5 cross-linking and increases antitumour effect against colon cancer.

PubMed

De Miguel, Diego; Gallego-Lleyda, Ana; Ayuso, José María; Pejenaute-Ochoa, Dolores; Jarauta, Vidal; Marzo, Isabel; Fernández, Luis J; Ochoa, Ignacio; Conde, Blanca; Anel, Alberto; Martinez-Lostao, Luis

2016-12-28

During the last years, a great effort has been invested into developing new TRAIL formulations with increased bioactivity, trying to overcome the resistance to conventional soluble TRAIL (sTRAIL) exhibited by many primary tumours. In our group, we have generated artificial lipid nanoparticles decorated with sTRAIL (LUV-TRAIL), emulating the physiological TRAIL-containing exosomes by which T-cells release TRAIL upon activation. We already demonstrated that LUV-TRAIL has greater cytotoxicity against both chemoresistant haematologic tumour cells and epithelial carcinoma cells compared to a form of sTRAIL similar to that used in clinical trials. In this study we have tested LUV-TRAIL in several human colon cancer cell lines with different sensitivity to sTRAIL. LUV-TRAIL significantly improved sTRAIL cytotoxicity in all colon cancer cell lines tested. Trying to ascertain the molecular mechanism by which LUV-TRAIL exhibited improved cytotoxicity, we demonstrated that TRAIL-coated lipid nanoparticles were able to activate DR5 more efficiently than sTRAIL, and this relied on LUV-TRAIL ability to promote DR5 clustering on the cell surface. Moreover, we show that TRAIL molecules are arranged in higher order oligomers only in LUV-TRAIL, which may explain their enhanced DR5 clustering ability. Finally, LUV-TRAIL showed significantly better antitumour activity than sTRAIL in an in vivo model using HCT-116 xenograft tumours in nude mice, validating its potential clinical application. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Reconnection-Driven Coronal-Hole Jets with Gravity and Solar Wind

NASA Technical Reports Server (NTRS)

Karpen, J. T.; Devore, C. R.; Antiochos, S. K.; Pariat, E.

2017-01-01

Coronal-hole jets occur ubiquitously in the Sun's coronal holes, at EUV and X-ray bright points associated with intrusions of minority magnetic polarity. The embedded-bipole model for these jets posits that they are driven by explosive, fast reconnection between the stressed closed field of the embedded bipole and the open field of the surrounding coronal hole. Previous numerical studies in Cartesian geometry, assuming uniform ambient magnetic field and plasma while neglecting gravity and solar wind, demonstrated that the model is robust and can produce jet-like events in simple configurations. We have extended these investigations by including spherical geometry,gravity, and solar wind in a nonuniform, coronal hole-like ambient atmosphere. Our simulations confirm that the jet is initiated by the onset of a kink-like instability of the internal closed field, which induces a burst of reconnection between the closed and external open field, launching a helical jet. Our new results demonstrate that the jet propagation is sustained through the outer corona, in the form of a traveling nonlinear Alfven wave front trailed by slower-moving plasma density enhancements that are compressed and accelerated by the wave. This finding agrees well with observations of white-light coronal-hole jets, and can explain microstreams and torsional Alfven waves detected in situ in the solar wind. We also use our numerical results to deduce scaling relationships between properties of the coronal source region and the characteristics of the resulting jet, which can be tested against observations.

Reaction Kernel Structure of a Slot Jet Diffusion Flame in Microgravity

NASA Technical Reports Server (NTRS)

Takahashi, F.; Katta, V. R.

2001-01-01

Diffusion flame stabilization in normal earth gravity (1 g) has long been a fundamental research subject in combustion. Local flame-flow phenomena, including heat and species transport and chemical reactions, around the flame base in the vicinity of condensed surfaces control flame stabilization and fire spreading processes. Therefore, gravity plays an important role in the subject topic because buoyancy induces flow in the flame zone, thus increasing the convective (and diffusive) oxygen transport into the flame zone and, in turn, reaction rates. Recent computations show that a peak reactivity (heat-release or oxygen-consumption rate) spot, or reaction kernel, is formed in the flame base by back-diffusion and reactions of radical species in the incoming oxygen-abundant flow at relatively low temperatures (about 1550 K). Quasi-linear correlations were found between the peak heat-release or oxygen-consumption rate and the velocity at the reaction kernel for cases including both jet and flat-plate diffusion flames in airflow. The reaction kernel provides a stationary ignition source to incoming reactants, sustains combustion, and thus stabilizes the trailing diffusion flame. In a quiescent microgravity environment, no buoyancy-induced flow exits and thus purely diffusive transport controls the reaction rates. Flame stabilization mechanisms in such purely diffusion-controlled regime remain largely unstudied. Therefore, it will be a rigorous test for the reaction kernel correlation if it can be extended toward zero velocity conditions in the purely diffusion-controlled regime. The objectives of this study are to reveal the structure of the flame-stabilizing region of a two-dimensional (2D) laminar jet diffusion flame in microgravity and develop a unified diffusion flame stabilization mechanism. This paper reports the recent progress in the computation and experiment performed in microgravity.

Comparing impacts between formal and informal recreational trails.

PubMed

Pickering, Catherine Marina; Norman, Patrick

2017-05-15

Globally there are hundreds of thousands of kilometres of recreational trails traversing natural areas of high conservation value: but what are their impacts and do impacts differ among trails? We compared the effects of four common types of recreational trails [(1) narrow and (2) medium width informal bare earth trails and (3) gravel and (4) tarmac/concrete formal trails] on vegetation adjacent to trails in a high conservation value plant community that is popular for mountain biking and hiking in Australia. Plant species composition was recorded in quadrats along the edge of the four types of trails and in control sites away from trails. Vegetation cover, the cover of individual growth forms, and species richness along the edges of all four types of trails were similar to the controls, although the wider trails affected plant composition, with the tarmac and gravel trails favouring different species. With very few comparative studies, more research is required to allow managers and researchers to directly compare differences in the severity and types of impacts on vegetation among trails. In the meantime, limiting damage to vegetation on the edge of hardened trails during construction, use and maintenance is important, and hardening trails may not always be appropriate. Copyright © 2016. Published by Elsevier Ltd.

Earth observations taken by the Expedition Seven crew

NASA Image and Video Library

2003-08-17

ISS007-E-12858 (17 August 2003) --- This view was taken by an Expedition 7 crewmember onboard the International Space Station (ISS). Sunlight reflects off of the lakes of Quetico Provincial Park, Ontario. The area lies between Lake Superior and Lake of the Woods, just north of the USA-Canadian border. The long vertical clouds in the image are condensation trails produced in the wake of jet airplanes.

Full-Scale Wind-Tunnel Investigation of a Jet Flap in Conjunction with a Plain Flap with Blowing Boundary-Layer Control on a 35 deg Sweptback-Wing Airplane

NASA Technical Reports Server (NTRS)

Aoyagi, Kiyoshi; Hickey, David H.

1959-01-01

Previous investigations have shown that increased blowing at the hinge-line radius of a plain flap will give flap lift increases above that realized with boundary-layer control. Other experiments and theory have shown that blowing from a wing trailing edge, through the jet flap effect, produced lift increases. The present investigation was made to determine whether blowing simultaneously at the hinge-line radius and trailing edge would be more effective than blowing separately at either location. The tests were made at a Reynolds number of 4.5 x 10(exp 6) with a 35 deg sweptback-wing airplane. For this report, only the lift data are presented. Of the three flap blowing arrangements tested, blowing distributed between the trailing edge and the hinge-line radius of a plain flap was found to be superior to blowing at either location separately at the plain flap deflections of interest. Comparison of estimated and experimental jet flap effectiveness was fair.

SAHM:VisTrails (Software for Assisted Habitat Modeling for VisTrails): training course

USGS Publications Warehouse

Holcombe, Tracy

2014-01-01

VisTrails is an open-source management and scientific workflow system designed to integrate the best of both scientific workflow and scientific visualization systems. Developers can extend the functionality of the VisTrails system by creating custom modules for bundled VisTrails packages. The Invasive Species Science Branch of the U.S. Geological Survey (USGS) Fort Collins Science Center (FORT) and the U.S. Department of the Interior’s North Central Climate Science Center have teamed up to develop and implement such a module—the Software for Assisted Habitat Modeling (SAHM). SAHM expedites habitat modeling and helps maintain a record of the various input data, the steps before and after processing, and the modeling options incorporated in the construction of an ecological response model. There are four main advantages to using the SAHM:VisTrails combined package for species distribution modeling: (1) formalization and tractable recording of the entire modeling process; (2) easier collaboration through a common modeling framework; (3) a user-friendly graphical interface to manage file input, model runs, and output; and (4) extensibility to incorporate future and additional modeling routines and tools. In order to meet increased interest in the SAHM:VisTrails package, the FORT offers a training course twice a year. The course includes a combination of lecture, hands-on work, and discussion. Please join us and other ecological modelers to learn the capabilities of the SAHM:VisTrails package.

3-Bromopyruvate enhances TRAIL-induced apoptosis in human nasopharyngeal carcinoma cells through CHOP-dependent upregulation of TRAIL-R2.

PubMed

Can, Zhou; Lele, Song; Zhirui, Zhang; Qiong, Pan; Yuzhong, Chen; Lingling, Liu; Surong, Zhao; Yiming, Sun; Pei, Zhang; Chenchen, Jiang; Liu, Hao

2017-08-01

Past reports have shown that the sensitivity of cancer cells to TRAIL-induced apoptosis is related to their expression of TRAIL-death receptors on the cell surface. However, the level of TRAIL-death receptors expression on cancer cells is always low. Our previous research showed that nasopharyngeal carcinoma (NPC) cells have a poor sensitivity to low doses of TRAIL. Here, we evaluated combined treatment with the energy inhibitor 3-bromopyruvate (3BP) and TRAIL as a method to produce an increased apoptotic response in NPC cells. The results showed that 3BP and TRAIL together produced higher cytotoxicity and increased TRAIL-R2 expression in NPC cells compared with the effects of either 3BP or TRAIL alone. These findings led us to hypothesize that 3BP may sensitize NPC cells to TRAIL. 3BP is a metabolic blocker that inhibits hexokinase II activity, suppresses ATP production, and induces endoplasmic reticulum (ER) stress. Our results showed that 3BP also activated AMP-activated protein kinase, which we found to play an important role in the induction of ER stress by 3BP. Furthermore, the induction of TRAIL-R2 expression and the sensitization of the NPC cells to TRAIL by 3BP were reduced when we inhibited the expression of CHOP. Taken together, our results showed that a low dose of 3BP sensitized NPC cells to TRAIL-induced apoptosis by the upregulation of CHOP, which was mediated by the activation of AMP-activated protein kinase and ER stress. The results showed that 3BP is a promising candidate agent for enhancing the therapeutic response to TRAIL in NPC.

Trail-following responses of the Argentine ant,Iridomyrmex humilis (Mayr), to a synthetic trail pheromone component and analogs.

PubMed

Van Vorhis Key, S E; Baker, T C

1982-01-01

Behavioral evidence indicates that (Z)-9-hexadecenal (Z9-16∶ALD) is a trail pheromone component ofIridomyrmex humilis, and that the true trail pheromone may be multicomponent. Trail-following responses ofI. humilis workers to several concentrations of syntheticZ9-16∶ALD, a constituent of the Pavan's gland, were found to be comparable to responses to gaster extract trails containing ca. 100 times lessZ9-16∶ALD. Of the five aldehyde analogs tested, only (Z)-7-hexadecenal (Z7-16∶ALD) elicited significant trail-following. However, following responses to severalZ9-16∶ALD-Z7-16∶ALD combinations were lower than responses toZ9-16∶ALD alone. Trails on filter paper of biologically relevant concentrations ofZ9-16∶ALD lose activity within 2 hr in the laboratory. The release rate ofZ9-16∶ALD measured from filter paper trails was 0.25 ± 0.10 pg/cm-sec. This was used to estimate the trail-following threshold for this compound of Argentine ant workers.

The gluon condensation at high energy hadron collisions

NASA Astrophysics Data System (ADS)

Zhu, Wei; Lan, Jiangshan

2017-03-01

We report that the saturation/CGC model of gluon distribution is unstable under action of the chaotic solution in a nonlinear QCD evolution equation, and it evolves to the distribution with a sharp peak at the critical momentum. We find that this gluon condensation is caused by a new kind of shadowing-antishadowing effects, and it leads to a series of unexpected effects in high energy hadron collisions including astrophysical events. For example, the extremely intense fluctuations in the transverse-momentum and rapidity distributions of the gluon jets present the gluon-jet bursts; a sudden increase of the proton-proton cross sections may fill the GZK suppression; the blocking QCD evolution will restrict the maximum available energy of the hadron-hadron colliders.

Low-Speed Wind-Tunnel Investigation to Determine the Aerodynamic Characteristics of a Rectangular Wing Equipped with a Full-Span and an Inboard Half-Span Jet-Augmented Flap Deflected 55 deg

NASA Technical Reports Server (NTRS)

Gainer, Thomas G.

1959-01-01

An investigation to determine the aerodynamic characteristics of a rectangular wing equipped with a full-span and an inboard half-span jet-augmented flap has been made in the Langley 300 MPH 7- by 10-foot tunnel. The wing had an aspect ratio of 8.3 and a thickness-chord ratio of 0.167. A jet of air was blown backward through a small gap, tangentially to the upper surface of a round trailing edge, and was separated from the trailing edge by a very small flap at an angle of 55 deg with respect to the wing-chord plane. The results of the investigation showed that the ratio of total lift to jet-reaction lift for the wing was about 35 percent less for the half-span jet-augmented flap than for the full-span jet-augmented flap. The reduction of the span of the jet-augmented flap from full to half span reduced the maximum value of jet-circulation lift coefficient that could be produced from about 6.8 to a value of about 2.2. The half-span jet- augmented flap gave thrust recoveries considerably poorer than those obtained with the full-span jet-augmented flap. Large nose-down pitching- moment coefficients were produced by the half-span flap, with the greater part of these being the result of the larger jet reactions required to produce a given lift for the half-spin flap compared with that required for the full-span flap.

Estimating the economic value and impacts of recreational trails: a case study of the Virginia creeper rail trail

Treesearch

J. Michael Bowker; John C. Bergstrom; Joshua Gill

2007-01-01

Many communities are interested in developing and maintaining recreational trails to benefit trail users and as tourist attractions to stimulate economic growth. In this paper, a study is described which estimates the net economic value to trail users and the local economic impacts of the Virginia Creeper Rail Trail in south-western Virginia, USA. The monetary...

30 CFR 75.602 - Trailing cable junctions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Trailing cable junctions. 75.602 Section 75.602... MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Trailing Cables § 75.602 Trailing cable junctions. [Statutory Provision] When two or more trailing cables junction to the same distribution center, means shall...

Experimental and simulated control of lift using trailing edge devices

NASA Astrophysics Data System (ADS)

Cooperman, A.; Blaylock, M.; van Dam, C. P.

2014-12-01

Two active aerodynamic load control (AALC) devices coupled with a control algorithm are shown to decrease the change in lift force experienced by an airfoil during a change in freestream velocity. Microtabs are small (1% chord) surfaces deployed perpendicular to an airfoil, while microjets are pneumatic jets with flow perpendicular to the surface of the airfoil near the trailing edge. Both devices are capable of producing a rapid change in an airfoil's lift coefficient. A control algorithm for microtabs has been tested in a wind tunnel using a modified S819 airfoil, and a microjet control algorithm has been simulated for a NACA 0012 airfoil using OVERFLOW. In both cases, the AALC devices have shown the ability to mitigate the changes in lift during a gust.

Jet Flap Stator Blade Test in the High Reaction Turbine Blade Cascade Tunnel

NASA Image and Video Library

1970-03-21

A researcher examines the setup of a jet flap blade in the High Reaction Turbine Blade Cascade Tunnel at the National Aeronautics and Space Administration (NASA) Lewis Research Center. Lewis researchers were seeking ways to increase turbine blade loading on aircraft engines in an effort to reduce the overall size and weight of engines. The ability of each blade to handle higher loads meant that fewer stages and fewer blades were required. This study analyzed the performance of a turbine blade using a jet flap and high loading. A jet of air was injected into the main stream from the pressure surface near the trailing edge. The jet formed an aerodynamic flap which deflected the flow and changed the circulation around the blade and thus increased the blade loading. The air jet also reduced boundary layer thickness. The jet-flap blade design was appealing because the cooling air may also be used for the jet. The performance was studied in a two-dimensional cascade including six blades. The researcher is checking the jet flat cascade with an exit survey probe. The probe measured the differential pressure that was proportional to the flow angle. The blades were tested over a range of velocity ratios and three jet flow conditions. Increased jet flow improved the turning and decreased both the weight flow and the blade loading. However, high blade loadings were obtained at all jet flow conditions.

30 CFR 75.828 - Trailing cable pulling.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Trailing cable pulling. 75.828 Section 75.828... Longwalls § 75.828 Trailing cable pulling. The trailing cable must be de-energized prior to being pulled by... procedures must be followed when pulling the trailing cable with equipment other than the continuous mining...

RECONNECTION-DRIVEN CORONAL-HOLE JETS WITH GRAVITY AND SOLAR WIND

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

Karpen, J. T.; DeVore, C. R.; Antiochos, S. K.

Coronal-hole jets occur ubiquitously in the Sun's coronal holes, at EUV and X-ray bright points associated with intrusions of minority magnetic polarity. The embedded-bipole model for these jets posits that they are driven by explosive, fast reconnection between the stressed closed field of the embedded bipole and the open field of the surrounding coronal hole. Previous numerical studies in Cartesian geometry, assuming uniform ambient magnetic field and plasma while neglecting gravity and solar wind, demonstrated that the model is robust and can produce jet-like events in simple configurations. We have extended these investigations by including spherical geometry, gravity, and solarmore » wind in a nonuniform, coronal hole-like ambient atmosphere. Our simulations confirm that the jet is initiated by the onset of a kink-like instability of the internal closed field, which induces a burst of reconnection between the closed and external open field, launching a helical jet. Our new results demonstrate that the jet propagation is sustained through the outer corona, in the form of a traveling nonlinear Alfvén wave front trailed by slower-moving plasma density enhancements that are compressed and accelerated by the wave. This finding agrees well with observations of white-light coronal-hole jets, and can explain microstreams and torsional Alfvén waves detected in situ in the solar wind. We also use our numerical results to deduce scaling relationships between properties of the coronal source region and the characteristics of the resulting jet, which can be tested against observations.« less

Experimental Investigation of Jet-Induced Mixing of a Large Liquid Hydrogen Storage Tank

NASA Technical Reports Server (NTRS)

Lin, C. S.; Hasan, M. M.; Vandresar, N. T.

1994-01-01

Experiments have been conducted to investigate the effect of fluid mixing on the depressurization of a large liquid hydrogen storage tank. The test tank is approximately ellipsoidal, having a volume of 4.89 m(exp 3) and an average wall heat flux of 4.2 W/m(exp 2) due to external heat input. A mixer unit was installed near the bottom of the tank to generate an upward directed axial jet flow normal to the liquid-vapor interface. Mixing tests were initiated after achieving thermally stratified conditions in the tank either by the introduction of hydrogen gas into the tank or by self-pressurization due to ambient heat leak through the tank wall. The subcooled liquid jet directed towards the liquid-vapor interface by the mixer induced vapor condensation and caused a reduction in tank pressure. Tests were conducted at two jet submergence depths for jet Reynolds numbers from 80,000 to 495,000 and Richardson numbers from 0.014 to 0.52. Results show that the rate of tank pressure change is controlled by the competing effects of subcooled jet flow and the free convection boundary layer flow due to external tank wall heating. It is shown that existing correlations for mixing time and vapor condensation rate based on small scale tanks may not be applicable to large scale liquid hydrogen systems.

36 CFR 13.1308 - Harding Icefield Trail.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Harding Icefield Trail. 13... Provisions § 13.1308 Harding Icefield Trail. The Harding Icefield Trail from the junction with the main paved trail near Exit Glacier to the emergency hut near the terminus is closed to— (a) Camping within 1/8 mile...

Trails research: where do we go from here?

Treesearch

Michael A. Schuett; Patricia Seiser

2002-01-01

This paper describes a recent study focusing on trails research needs. This study was supported by American Trails. Using a Delphi technique, 86 trails experts representing a variety of federal, state and local agencies, nonprofits, and trail uses were queried by email on trails research needs. A Delphi technique is a prognostic tool for dealing with complex problems...

A study of ingestion and dispersion of engine exhaust products in trailing vortex systems

NASA Technical Reports Server (NTRS)

Nielsen, J. N.; Stahara, S. S.; Woolley, J. P.

1973-01-01

Analysis has been made of the ingestion and dispersion of engine exhaust products into the trailing vortex system of supersonic aircraft flying in the stratosphere. The rate of mixing between the supersonic jet and the co-flowing supersonic stream was found to be an order of magnitude less than would be expected on the basis of subsonic eddy-viscosity results. The length of the potential core was 66 nozzle exit radii so that the exhaust gases remain at elevated temperatures and concentrations over much longer distances than previsously estimated. Ingestion started at the end of the potential core and all hot gas from the engine was ingested into the trailing vortex within two core lengths. Comparison between the buoyancy calculations for the supersonic case with nondimensionalized subsonic aircraft contrail data on wake spreading showed good agreement. Velocity and temperature profiles have been specified at various stages of the wake, and the analysis in this report can be used to predict variations of concentrations of species such as nitrogen oxides under conditions of chemical reaction.

Miles In Trail (MIT) Restrictions: A Perspective

NASA Technical Reports Server (NTRS)

Kopardekar, Parimal; Green, Steven; Roherty, Tom; Aston, John

2003-01-01

Miles-in-trail restrictions are issued to meet the airport and/or airspace capacity. The purpose of this paper is to review the currently practiced miles-in-trail operations for traffic flow management at a typical en route Air Traffic Control Center. The paper describes roles and considerations of both traffic management coordinators and the controllers in planning, coordination, execution, and monitoring of miles-in-trail restrictions. The paper addresses the type of decisions that traffic management coordinators must make and the different information required to plan and monitor miles-in-trail restrictions. The implications of miles-in-trail restrictions on controller workload are also addressed. Using the Cleveland center as an example, the paper also identified some challenging traffic situations that required miles-in-trail restrictions on a regular basis. The paper is expected to benefit the research and development community as it provides the current challenges in traffic flow management and strengths and weakness of miles-in-trail operations.

Aggregation-fragmentation-diffusion model for trail dynamics

DOE PAGES

Kawagoe, Kyle; Huber, Greg; Pradas, Marc; ...

2017-07-21

We investigate statistical properties of trails formed by a random process incorporating aggregation, fragmentation, and diffusion. In this stochastic process, which takes place in one spatial dimension, two neighboring trails may combine to form a larger one, and also one trail may split into two. In addition, trails move diffusively. The model is defined by two parameters which quantify the fragmentation rate and the fragment size. In the long-time limit, the system reaches a steady state, and our focus is the limiting distribution of trail weights. We find that the density of trail weight has power-law tail P(w)~w –γ formore » small weight w. We obtain the exponent γ analytically and find that it varies continuously with the two model parameters. In conclusion, the exponent γ can be positive or negative, so that in one range of parameters small-weight trails are abundant and in the complementary range they are rare.« less

Investigating the anatomy of magnetosheath jets - MMS observations

NASA Astrophysics Data System (ADS)

Karlsson, Tomas; Plaschke, Ferdinand; Hietala, Heli; Archer, Martin; Blanco-Cano, Xóchitl; Kajdič, Primož; Lindqvist, Per-Arne; Marklund, Göran; Gershman, Daniel J.

2018-04-01

We use Magnetosphere Multiscale (MMS) mission data to investigate a small number of magnetosheath jets, which are localized and transient increases in dynamic pressure, typically due to a combined increase in plasma velocity and density. For two approximately hour-long intervals in November, 2015 we found six jets, which are of two distinct types. (a) Two of the jets are associated with the magnetic field discontinuities at the boundary between the quasi-parallel and quasi-perpendicular magnetosheath. Straddling the boundary, the leading part of these jets contains an ion population similar to the quasi-parallel magnetosheath, while the trailing part contains ion populations similar to the quasi-perpendicular magnetosheath. Both populations are, however, cooler than the surrounding ion populations. These two jets also have clear increases in plasma density and magnetic field strength, correlated with a velocity increase. (b) Three of the jets are found embedded within the quasi-parallel magnetosheath. They contain ion populations similar to the surrounding quasi-parallel magnetosheath, but with a lower temperature. Out of these three jets, two have a simple structure. For these two jets, the increases in density and magnetic field strength are correlated with the dynamic pressure increases. The other jet has a more complicated structure, and no clear correlations between density, magnetic field strength and dynamic pressure. This jet has likely interacted with the magnetosphere, and contains ions similar to the jets inside the quasi-parallel magnetosheath, but shows signs of adiabatic heating. All jets are associated with emissions of whistler, lower hybrid, and broadband electrostatic waves, as well as approximately 10 s period electromagnetic waves with a compressional component. The latter have a Poynting flux of up to 40 µW m-2 and may be energetically important for the evolution of the jets, depending on the wave excitation mechanism. Only one of the jets is

Recreation trails in Maine and New Hampshire: A comparison of notorized, non-motorized, and non-mechanized trails

Treesearch

Ethel Wilkerson; Andrew. Whitman

2010-01-01

We sampled 112 trail segments in Maine and New Hampshire to assess the impact of motorized and non-motorized recreation on trail conditions and stream sedimentation. On each segment, we assessed physical trail conditions (width, cross-sectional area, occurrence of excessively muddy and rutted/eroded sections), presence of trash, and sedimentation at stream crossings....

Transient interaction between a reaction control jet and a hypersonic crossflow

NASA Astrophysics Data System (ADS)

Miller, Warrick A.; Medwell, Paul R.; Doolan, Con J.; Kim, Minkwan

2018-04-01

This paper presents a numerical study that focuses on the transient interaction between a reaction control jet and a hypersonic crossflow with a laminar boundary layer. The aim is to better understand the underlying physical mechanisms affecting the resulting surface pressure and control force. Implicit large-eddy simulations were performed with a round, sonic, perfect air jet issuing normal to a Mach 5 crossflow over a flat plate with a laminar boundary layer, at a jet-to-crossflow momentum ratio of 5.3 and a pressure ratio of 251. The pressure distribution induced on the flat plate is unsteady and is influenced by vortex structures that form around the jet. A horseshoe vortex structure forms upstream and consists of six vortices: two quasi-steady vortices and two co-rotating vortex pairs that periodically coalesce. Shear-layer vortices shed periodically and cause localised high pressure regions that convect downstream with constant velocity. A longitudinal counter-rotating vortex pair is present downstream of the jet and is formed from a series of trailing vortices which rotate about a common axis. Shear-layer vortex shedding causes periodic deformation of barrel and bow shocks. This changes the location of boundary layer separation which also affects the normal force on the plate.

Hiking shared-use single-track trails: a look at hikers and hunters along the Falls Lake Trail

Treesearch

Christopher M. Snow; Roger L. Moore

2007-01-01

The Falls Lake Trail, a 26.8-mile, single-track pedestrian trail located near the Research Triangle Region of North Carolina, traverses lands managed by the United States Army Corps of Engineers; North Carolina Division of Parks and Recreation; North Carolina Division of Wildlife Resources; and Wake County Parks, Recreation and Open Space. The non-profit trail advocacy...

LES of High-Reynolds-Number Coanda Flow Separating from a Rounded Trailing Edge of a Circulation Control Airfoil

NASA Technical Reports Server (NTRS)

Nichino, Takafumi; Hahn, Seonghyeon; Shariff, Karim

2010-01-01

This slide presentation reviews the Large Eddy Simulation of a high reynolds number Coanda flow that is separated from a round trailing edge of a ciruclation control airfoil. The objectives of the study are: (1) To investigate detailed physics (flow structures and statistics) of the fully turbulent Coanda jet applied to a CC airfoil, by using LES (2) To compare LES and RANS results to figure out how to improve the performance of existing RANS models for this type of flow.

An analysis of state legislation on community trails.

PubMed

Eyler, Amy; Lankford, Tina; Chriqui, Jamie; Evenson, Kelly R; Kruger, Judy; Tompkins, Nancy; Voorhees, Carolyn; Zieff, Susan; Aytur, Semra; Brownson, Ross

2010-03-01

Trails provide opportunities for recreation, transportation and activity. The purpose of this article is to describe state legislation related to community trails, to analyze legislation content, and to evaluate legislation on inclusion of evidence-informed elements. State trail legislation from 2001 to 2008 was identified using online legislative databases. An analysis of evidence-informed elements included in the legislation was conducted. These elements included: funding, liability, accessibility, connectivity, and maintenance. Of the total 991 trail bills, 516 (52.0%) were appropriations bills, of which 167 (32.2%) were enacted. We analyzed 475 (48%) nonappropriation trail bills of which 139 (29.3%) were enacted. The percentage of enactment of appropriations bills decreased over time while enactment of nonappropriations trail bills increased. Over half of the nonappropriations trail bills included at least 1 evidence-informed element, most commonly funding. Few bills contained liability, connectivity, accessibility, or maintenance. There is opportunity for providing evidence-informed information to policy-makers to potentially influence bill content. The number of bills with a funding element demonstrates that fiscal support for trails is an important policy lever that state legislatures may use to support trails. Lastly, trails should be considered in over-all state-level physical activity legislation to provide opportunities for communities to be active.

Wet active chevron nozzle for controllable jet noise reduction

NASA Technical Reports Server (NTRS)

Thomas, Russell H. (Inventor); Kinzie, Kevin W. (Inventor)

2011-01-01

Disposed at or toward the trailing edge of one or more nozzles associated with a jet engine are injection ports which can selectively be made to discharge a water stream into a nozzle flow stream for the purpose of increasing turbulence in somewhat of a similar fashion as mechanically disposed chevrons have done in the known art. Unlike mechanically disposed chevrons of the known art, the fluid flow may be secured thereby increasing the engine efficiency. Various flow patterns, water pressures, orifice designs or other factors can be made operative to provide desired performance characteristics.

AUTOMATIC DIRT TRAIL ANALYSIS IN DERMOSCOPY IMAGES

PubMed Central

Cheng, Beibei; Stanley, R. Joe; Stoecker, William V.; Osterwise, Christopher T.P.; Stricklin, Sherea M.; Hinton, Kristen A.; Moss, Randy H.; Oliviero, Margaret; Rabinovitz, Harold S.

2011-01-01

Basal cell carcinoma (BCC) is the most common cancer in the U.S. Dermatoscopes are devices used by physicians to facilitate the early detection of these cancers based on the identification of skin lesion structures often specific to BCCs. One new lesion structure, referred to as dirt trails, has the appearance of dark gray, brown or black dots and clods of varying sizes distributed in elongated clusters with indistinct borders, often appearing as curvilinear trails. In this research, we explore a dirt trail detection and analysis algorithm for extracting, measuring, and characterizing dirt trails based on size, distribution, and color in dermoscopic skin lesion images. These dirt trails are then used to automatically discriminate BCC from benign skin lesions. For an experimental data set of 35 BCC images with dirt trails and 79 benign lesion images, a neural network-based classifier achieved a 0.902 area under a receiver operating characteristic curve using a leave-one-out approach, demonstrating the potential of dirt trails for BCC lesion discrimination. PMID:22233099

A Model for Jet-Surface Interaction Noise Using Physically Realizable Upstream Turbulence Conditions

NASA Technical Reports Server (NTRS)

Afsar, Mohammed Z.; Leib, Stewart J.; Bozak, Richard F.

2015-01-01

This paper is a continuation of previous work in which a generalized Rapid Distortion Theory (RDT) formulation was used to model low-frequency trailing-edge noise. The research was motivated by proposed next-generation aircraft configurations where the exhaust system is tightly integrated with the airframe. Data from recent experiments at NASA on the interaction between high-Reynolds-number subsonic jet flows and an external flat plate showed that the power spectral density (PSD) of the far-field pressure underwent considerable amplification at low frequencies. For example, at the 900 observation angle, the low-frequency noise could be as much as 10dB greater than the jet noise itself. In this paper, we present predictions of the noise generated by the interaction of a rectangular jet with the trailing edge of a semi-infinite flat plate. The calculations are based on a formula for the acoustic spectrum of this noise source derived from an exact formal solution of the linearized Euler equations involving (in this case) one arbitrary convected scalar quantity and a Rayleigh equation Green's function. A low-frequency asymptotic approximation for the Green's function based on a two-dimensional mean flow is used in the calculations along with a physically realizable upstream turbulence spectrum, which includes a finite de-correlation region. Numerical predictions, based on three-dimensional RANS solutions for a range of subsonic acoustic Mach number jets and nozzle aspect ratios are compared with experimental data. Comparisons of the RANS results with flow data are also presented for selected cases. We find that a finite decorrelation region increases the low-frequency algebraic decay (the low frequency "rolloff") of the acoustic spectrum with angular frequency thereby producing much closer agreement with noise data for Strouhal numbers less than 0.1. Secondly, the large-aspectratio theory is able to predict the low-frequency amplification due to the jet

A Model for Jet-Surface Interaction Noise Using Physically Realizable Upstream Turbulence Conditions

NASA Technical Reports Server (NTRS)

Afsar, Mohammed Z.; Leib, Stewart J.; Bozak, Richard F.

2016-01-01

This paper is a continuation of previous work in which a generalized Rapid Distortion Theory (RDT) formulation was used to model low-frequency trailing-edge noise. The research was motivated by proposed next-generation aircraft configurations where the exhaust system is tightly integrated with the airframe. Data from recent experiments at NASA on the interaction between high-Reynolds-number subsonic jet flows and an external flat plate showed that the power spectral density (PSD) of the far-field pressure underwent considerable amplification at low frequencies. For example, at the 90deg observation angle, the low-frequency noise could be as much as 10 dB greater than the jet noise itself. In this paper, we present predictions of the noise generated by the interaction of a rectangular jet with the trailing edge of a semi-infinite flat plate. The calculations are based on a formula for the acoustic spectrum of this noise source derived from an exact formal solution of the linearized Euler equations involving (in this case) one arbitrary convected scalar quantity and a Rayleigh equation Green's function. A low-frequency asymptotic approximation for the Green's function based on a two-dimensional mean flow is used in the calculations along with a physically realizable upstream turbulence spectrum, which includes a finite decorrelation region. Numerical predictions of the sound field, based on three-dimensional RANS solutions to determine the mean flow, turbulent kinetic energy and turbulence length and time scales, for a range of subsonic acoustic Mach number jets and nozzle aspect ratios are compared with experimental data. Comparisons of the RANS results with flow data are also presented for selected cases. We find that a finite decorrelation region in the turbulence spectrum increases the low-frequency algebraic decay (the low frequency "roll-off") of the acoustic spectrum with angular frequency thereby producing much closer agreement with noise data for Strouhal

30 CFR 75.600 - Trailing cables; flame resistance.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Trailing cables; flame resistance. 75.600... SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Trailing Cables § 75.600 Trailing cables; flame resistance. [Statutory Provisions] Trailing cables used in coal mines shall meet the...

30 CFR 75.606 - Protection of trailing cables.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Protection of trailing cables. 75.606 Section... AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Trailing Cables § 75.606 Protection of trailing cables. [Statutory Provisions] Trailing cables shall be adequately protected to prevent damage by...

Hiker preferences for trail features and maps

Treesearch

Roger E. McCay

1978-01-01

Hikers at a Pennsylvania state park were asked what items were essential to their trail experience. From a list of 18 items, an overwhelming majority of hikers wanted to see trail names and directional signs along a natural surfaced trail.

30 CFR 75.826 - High-voltage trailing cables.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false High-voltage trailing cables. 75.826 Section 75...-Voltage Longwalls § 75.826 High-voltage trailing cables. High-voltage trailing cables must: (a) Meet existing trailing cable requirements and the approval requirements of the high-voltage continuous mining...

30 CFR 77.604 - Protection of trailing cables.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Protection of trailing cables. 77.604 Section 77.604 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY... MINES Trailing Cables § 77.604 Protection of trailing cables. Trailing cables shall be adequately...

Jet Surface Interaction-Scrubbing Noise

NASA Technical Reports Server (NTRS)

Khavaran, Abbas

2013-01-01

Generation of sound due to scrubbing of a jet flow past a nearby solid surface is investigated within the framework of the generalized acoustic analogy theory. The analysis applies to the boundary layer noise generated at and near a wall, and excludes the scattered noise component that is produced at the leading or the trailing edge. While compressibility effects are relatively unimportant at very low Mach numbers, frictional heat generation and thermal gradient normal to the surface could play important roles in generation and propagation of sound in high speed jets of practical interest. A general expression is given for the spectral density of the far-field sound as governed by the variable density Pridmore- Brown equation. The propagation Green's function should be solved numerically starting with the boundary conditions on the surface and subject to specified mean velocity and temperature profiles between the surface and the observer. The equivalent sources of aerodynamic sound are associated with non-linear momentum flux and enthalpy flux terms that appear in the linearized Navier-Stokes equations. These multi-pole sources should be modeled and evaluated with input from a Reynolds-Averaged Navier-Stokes (RANS) solver with an appropriate turbulence model.

DNS investigation of the dynamical behaviour of trailing vortices in unbaffled stirred vessels at transitional Reynolds numbers

NASA Astrophysics Data System (ADS)

Başbuǧ, S.; Papadakis, G.; Vassilicos, J. C.

2017-06-01

Flow in an unbaffled stirred vessel agitated by a four-bladed radial impeller is investigated by using direct numerical simulations at Re = 320 and 1600. We observe fluctuations in the power consumption with a peak frequency at ca. three times the impeller rotational speed for both Reynolds numbers. It is discovered that these fluctuations are associated with a periodic event in the wake of the blades, which involves alternating growth and decay of the upper and lower cores of the trailing vortex pair as well as up-and-down swinging motion of the radial jet. Moreover, the phase relation between the wakes of the different blades is examined in detail. Further studies using fractal-shaped blades show that the exact blade shape does not have a strong influence on this phenomenon. However, the wake interaction between the blades, hence the number of blades, has a direct influence on the unsteadiness of trailing vortices.

36 CFR 212.21 - Pacific Crest National Scenic Trail.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Trail. 212.21 Section 212.21 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF... National Scenic Trail. The Pacific Crest National Scenic Trail as defined by the National Trails Systems Act, 82 Stat. 919, shall be administered primarily as a footpath and horseback riding trail by the...

30 CFR 77.606 - Energized trailing cables; handling.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Energized trailing cables; handling. 77.606... COAL MINES Trailing Cables § 77.606 Energized trailing cables; handling. Energized medium- and high-voltage trailing cables shall be handled only by persons wearing protective rubber gloves (see § 77.606-1...

CSX rail trestle conversion to ATV trail.

DOT National Transportation Integrated Search

2014-10-01

The Hatfield and McCoy Trail Authority (HMRRA) operates the Rockhouse ATV trail : between Man and Gilbert WV. Prior to this project, trail riders wishing to cross the Guyandotte : River had to ride the streets of Man, WV. The project goal was to prom...

TRAIL-CM4 fusion protein shows in vitro antibacterial activity and a stronger antitumor activity than solo TRAIL protein.

PubMed

Sang, Ming; Zhang, Jiaxin; Li, Bin; Chen, Yuqing

2016-06-01

A TRAIL-CM4 fusion protein in soluble form with tumor selective apoptosis and antibacterial functions was expressed in the Escherichia coli expression system and isolated through dialysis refolding and histidine-tag Nickel-affinity purification. Fresh Jurkat cells were treated with the TRAIL-CM4 fusion protein. Trypan blue staining and MTT analyses showed that, similar to a TRAIL positive control, Jurkat cell proliferation was significantly inhibited. Flow cytometry analyses using Annexin V-fluorescein revealed that Jurkat cells treated with the TRAIL-CM4 fusion protein exhibited increased apoptosis. Laser confocal microscopy showed that APB-CM4 and the fusion protein TRAIL-CM4 can bind to Jurkat cell membranes and initiate their destruction. ABP-CM4 enhances the antitumor activity of TRAIL by targeting and damaging the tumor cell membrane. In antibacterial experiments, agar well diffusion and bacterial growth inhibition curve assays revealed concentration-dependent TRAIL-CM4 antibacterial activity against Escherichia coli K12D31. The expressed TRAIL-CM4 fusion protein exhibited enhanced antitumor and antibacterial activities. Fusion protein expression allowed the two different proteins to function in combination. Copyright © 2016 Elsevier Inc. All rights reserved.

Analysis of experimental characteristics of multistage steam-jet electors of steam turbines

NASA Astrophysics Data System (ADS)

Aronson, K. E.; Ryabchikov, A. Yu.; Brodov, Yu. M.; Brezgin, D. V.; Zhelonkin, N. V.; Murmanskii, I. B.

2017-02-01

A series of questions for specification of physical gas dynamics model in flow range of steam-jet unit and ejector computation methodology, as well as functioning peculiarities of intercoolers, was formulated based on analysis of experimental characteristics of multistage team-jet steam turbines. It was established that coefficient defining position of critical cross-section of injected flow depends on characteristics of the "sound tube" zone. Speed of injected flow within this tube may exceed that of sound, and pressure jumps in work-steam decrease at the same time. Characteristics of the "sound tube" define optimal axial sizes of the ejector. According to measurement results, the part of steam condensing in the first-stage coolant constitutes 70-80% of steam amount supplied into coolant and is almost independent of air content in steam. Coolant efficiency depends on steam pressure defined by operation of steam-jet unit of ejector of the next stage after coolant of steam-jet stage, temperature, and condensing water flow. As a rule, steam entering content of steam-air mixture supplied to coolant is overheated with respect to saturation temperature of steam in the mixture. This should be taken into account during coolant computation. Long-term operation causes changes in roughness of walls of the ejector's mixing chamber. The influence of change of wall roughness on ejector characteristic is similar to the influence of reverse pressure of the steam-jet stage. Until some roughness value, injection coefficient of the ejector stage operating in superlimiting regime hardly changed. After reaching critical roughness, the ejector switches to prelimiting operating regime.

36 CFR 261.55 - National Forest System trails.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false National Forest System trails... PROHIBITIONS Prohibitions in Areas Designated by Order § 261.55 National Forest System trails. When provided by... National Forest System trail: (a) Being on a trail. (b) Using any type of vehicle prohibited by the order...

30 CFR 57.4057 - Underground trailing cables.

Code of Federal Regulations, 2013 CFR

2013-07-01

... and Control § 57.4057 Underground trailing cables. Underground trailing cables shall be accepted or... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Underground trailing cables. 57.4057 Section 57.4057 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL...

30 CFR 57.4057 - Underground trailing cables.

Code of Federal Regulations, 2012 CFR

2012-07-01

... and Control § 57.4057 Underground trailing cables. Underground trailing cables shall be accepted or... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Underground trailing cables. 57.4057 Section 57.4057 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL...

30 CFR 57.4057 - Underground trailing cables.

Code of Federal Regulations, 2014 CFR

2014-07-01

... and Control § 57.4057 Underground trailing cables. Underground trailing cables shall be accepted or... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Underground trailing cables. 57.4057 Section 57.4057 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL...

30 CFR 57.4057 - Underground trailing cables.

Code of Federal Regulations, 2011 CFR

2011-07-01

... and Control § 57.4057 Underground trailing cables. Underground trailing cables shall be accepted or... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Underground trailing cables. 57.4057 Section 57.4057 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL...

Angular and polarization trails from effective interactions of Majorana neutrinos at the LHeC

NASA Astrophysics Data System (ADS)

Duarte, Lucía; Zapata, Gabriel; Sampayo, Oscar A.

2018-05-01

We study the possibility of the LHeC facility to disentangle different new physics contributions to the production of heavy sterile Majorana neutrinos in the lepton number violating channel e-p→ lj+ + 3 jets (l_j≡e ,μ ). This is done investigating the angular and polarization trails of effective operators with distinct Dirac-Lorentz structure contributing to the Majorana neutrino production, which parameterize new physics from a higher energy scale. We study an asymmetry in the angular distribution of the final anti-lepton and the initial electron polarization effect on the number of signal events produced by the vectorial and scalar effective interactions, finding both analyses could well separate their contributions.

Pheromone disruption of Argentine ant trail integrity.

PubMed

Suckling, D M; Peck, R W; Manning, L M; Stringer, L D; Cappadonna, J; El-Sayed, A M

2008-12-01

Disruption of Argentine ant trail following and reduced ability to forage (measured by bait location success) was achieved after presentation of an oversupply of trail pheromone, (Z)-9-hexadecenal. Experiments tested single pheromone point sources and dispersion of a formulation in small field plots. Ant walking behavior was recorded and digitized by using video tracking, before and after presentation of trail pheromone. Ants showed changes in three parameters within seconds of treatment: (1) Ants on trails normally showed a unimodal frequency distribution of walking track angles, but this pattern disappeared after presentation of the trail pheromone; (2) ants showed initial high trail integrity on a range of untreated substrates from painted walls to wooden or concrete floors, but this was significantly reduced following presentation of a point source of pheromone; (3) the number of ants in the pheromone-treated area increased over time, as recruitment apparently exceeded departures. To test trail disruption in small outdoor plots, the trail pheromone was formulated with carnuba wax-coated quartz laboratory sand (1 g quartz sand/0.2 g wax/1 mg pheromone). The pheromone formulation, with a half-life of 30 h, was applied by rotary spreader at four rates (0, 2.5, 7.5, and 25 mg pheromone/m(2)) to 1- and 4-m(2) plots in Volcanoes National Park, Hawaii. Ant counts at bait cards in treated plots were significantly reduced compared to controls on the day of treatment, and there was a significant reduction in ant foraging for 2 days. These results show that trail pheromone disruption of Argentine ants is possible, but a much more durable formulation is needed before nest-level impacts can be expected.

Trail-following in termites: Evidence for a multicomponent system.

PubMed

Kaib, M; Bruinsma, O; Leuthold, R H

1982-09-01

Several African termite species from different subfamilies and different habitats are sensitive to trail-active extracts or to naturally laid trails from other species. Using single-extract bioassays, it is shown that the response threshold for trail-following is nearly identical for all tested species (except forHodotermes mossambicus). However, when termite workers have a choice between trails from their own species and from other species, conspecific trail-following is exclusively observed. This phenomenon can be counteracted by dilution (1∶10) of the conspecific trail-pheromone extract. Tests of the trail activity of various synthetic alcohols show that among these, the highest sensitivity of termite workers is to (Z)-3-dodecen-1-ol. Based on our experimental data, we postulate that, in addition to a generally active trail-pheromone constituent (an unsaturated primary C12 alcohol) or a pool of chemically closely related alcohols, other species-specific components are present in termite trails.

Trail-following behavior ofReticulitermes hesperus Banks (Isoptera: Rhinotermitidae).

PubMed

Grace, J K; Wood, D L; Frankie, G W

1988-02-01

The behavior ofReticulitermes hesperus Banks pseudergates (workers) was assessed on artificial trails containing different concentrations of sternal gland extract. On nongiadient trails, more pseudergates were recruited to trails of greater pheromone concentration, they traveled a greater distance without pausing, and their rate of locomotion increased over that observed on trails of lesser concentration (positive orthokinesis). Of the individuals pausing before completing trails of high concentration, fewer left the trails or reversed direction (negative klinokinesis) than on trails of lower concentration. Termites walking down concentration gradients failed to complete these trails to the low-concentration termini. At a point representing an average decrease of slightly more than 10-fold in the original concentration of pheromone, individuals reversed their direction of travel and returned to the high-concentration terminus. Termites walking up pheromone gradients proceeded to the high-concentration termini without reversing direction.R. hesperus pseudergates are thus able to orient along a gradient of trail pheromone by longitudinal klinotaxis.

High Temperature Ceramic Guide Vane Temperature and Pressure Distribution Calculation for Flow with Cooling Jets

NASA Technical Reports Server (NTRS)

Srivastava, Rakesh

2004-01-01

A ceramic guide vane has been designed and tested for operation under high temperature. Previous efforts have suggested that some cooling flow may be required to alleviate the high temperatures observed near the trailing edge region. The present report describes briefly a three-dimensional viscous analysis carried out to calculate the temperature and pressure distribution on the blade surface and in the flow path with a jet of cooling air exiting from the suction surface near the trailing edge region. The data for analysis was obtained from Dr. Craig Robinson. The surface temperature and pressure distribution along with a flowfield distribution is shown in the results. The surface distribution is also given in a tabular form at the end of the document.

NASA aircraft trailing vortex research

NASA Technical Reports Server (NTRS)

Mcgowan, W. A.

1971-01-01

A brief description is given of NASA's comprehensive program to study the aircraft trailing vortex problem. Wind tunnel experiments are used to develop the detailed processes of wing tip vortex formation and explore different means to either prevent trailing vortices from forming or induce early break-up. Flight tests provide information on trailing vortex system behavior behind large transport aircraft, both near the ground, as in the vicinity of the airport, and at cruise/holding pattern altitudes. Results from some flight tests are used to show how pilots might avoid the dangerous areas when flying in the vicinity of large transport aircraft. Other flight tests will be made to verify and evaluate trailing vortex elimination schemes developed in the model tests. Laser Doppler velocimeters being developed for use in the research program and to locate and measure vortex winds in the airport area are discussed. Field tests have shown that the laser Doppler velocimeter measurements compare well with those from cup anemometers.

21 CFR 1311.215 - Internal audit trail.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Internal audit trail. 1311.215 Section 1311.215... ORDERS AND PRESCRIPTIONS (Eff. 6-1-10) Electronic Prescriptions § 1311.215 Internal audit trail. (a) The... with audit trail functions. (6) For application service providers, attempted or successful annotation...

Travel to, and use of, twenty-one Michigan trails.

PubMed

Price, Anna E; Reed, Julian A; Grost, Lisa; Harvey, Christina; Mantinan, Karah

2013-03-01

This study examined trail use among 857 trail users on 21 trails in Michigan from 2008 to 2011 using a valid and reliable intercept survey. Most of the 857 participants traveled to the trail from their home (92.6%), lived within 15 min of the trails (74.8%), and used active transport to travel to the trails 69.7%. The odds of active transport to the trails were greater among those who had not graduated high school (OR=3.49; 95% CI=1.02, 11.99) and high school graduates (OR=7.432; 95% CI=2.02, 27.30) compared to college graduates. Whites and adults also had greater odds of active transport than non-Whites (OR=3.160, 95% CI: 1.65, 6.05), and older adults (OR=1.75; 95% CI: 1.20, 2.54). The majority of respondents (89.7%) reported using trails for recreational purposes. A significantly greater proportion of females (73.3%) compared to males (64.7%) reported using the trail with others. The findings from this study might enable health and parks and recreation professionals to better promote physical activity on trails. Copyright © 2013 Elsevier Inc. All rights reserved.

Discharge processes, electric field, and electron energy in ISUAL-recorded gigantic jets

NASA Astrophysics Data System (ADS)

Kuo, Cheng-Ling; Chou, J. K.; Tsai, L. Y.; Chen, A. B.; Su, H. T.; Hsu, R. R.; Cummer, S. A.; Frey, H. U.; Mende, S. B.; Takahashi, Y.; Lee, L. C.

2009-04-01

This article reports the first high time resolution measurements of gigantic jets from the Imager of Sprites and Upper Atmospheric Lightning (ISUAL) experiment. The velocity of the upward propagating fully developed jet stage of the gigantic jets was ˜107 m s-1, which is similar to that observed for downward sprite streamers. Analysis of spectral ratios for the fully developed jet emissions gives a reduced E field of 400-655 Td and average electron energy of 8.5-12.3 eV. These values are higher than those in the sprites but are similar to those predicted by streamer models, which implies the existence of streamer tips in fully developed jets. The gigantic jets studied here all contained two distinct photometric peaks. The first peak is from the fully developed jet, which steadily propagates from the cloud top (˜20 km) to the lower ionosphere at ˜90 km. We suggest that the second photometric peak, which occurs ˜1 ms after the first peak, is from a current wave or potential wave-enhanced emissions that originate at an altitude of ˜50 km and extend toward the cloud top. We propose that the fully developed jet serves as an extension of the local ionosphere and produces a lowered ionosphere boundary. As the attachment processes remove the charges, the boundary of the local ionosphere moves up. The current in the channel persists and its contact point with the ionosphere moves upward, which produces the upward surging trailing jets. Imager and photometer data indicate that the lightning activity associated with the gigantic jets likely is in-cloud, and thus the initiation of the gigantic jets is not directly associated with cloud-to-ground discharges.

Automatic dirt trail analysis in dermoscopy images.

PubMed

Cheng, Beibei; Joe Stanley, R; Stoecker, William V; Osterwise, Christopher T P; Stricklin, Sherea M; Hinton, Kristen A; Moss, Randy H; Oliviero, Margaret; Rabinovitz, Harold S

2013-02-01

Basal cell carcinoma (BCC) is the most common cancer in the US. Dermatoscopes are devices used by physicians to facilitate the early detection of these cancers based on the identification of skin lesion structures often specific to BCCs. One new lesion structure, referred to as dirt trails, has the appearance of dark gray, brown or black dots and clods of varying sizes distributed in elongated clusters with indistinct borders, often appearing as curvilinear trails. In this research, we explore a dirt trail detection and analysis algorithm for extracting, measuring, and characterizing dirt trails based on size, distribution, and color in dermoscopic skin lesion images. These dirt trails are then used to automatically discriminate BCC from benign skin lesions. For an experimental data set of 35 BCC images with dirt trails and 79 benign lesion images, a neural network-based classifier achieved a 0.902 are under a receiver operating characteristic curve using a leave-one-out approach. Results obtained from this study show that automatic detection of dirt trails in dermoscopic images of BCC is feasible. This is important because of the large number of these skin cancers seen every year and the challenge of discovering these earlier with instrumentation. © 2011 John Wiley & Sons A/S.

Trail pheromone disruption of red imported fire ant.

PubMed

Suckling, David M; Stringer, Lloyd D; Bunn, Barry; El-Sayed, Ashraf M; Vander Meer, Robert K

2010-07-01

The fire ant, Solenopsis invicta (Hymenoptera: Formicidae), is considered one of the most aggressive and invasive species in the world. Toxic bait systems are used widely for control, but they also affect non-target ant species and cannot be used in sensitive ecosystems such as organic farms and national parks. The fire ant uses recruitment pheromones to organize the retrieval of large food resources back to the colony, with Z,E-alpha-farnesene responsible for the orientation of workers along trails. We prepared Z,E-alpha-farnesene, (91% purity) from extracted E,E-alpha-farnesene and demonstrated disruption of worker trail orientation after presentation of an oversupply of this compound from filter paper point sources (30 microg). Trails were established between queen-right colony cells and food sources in plastic tubs. Trail-following behavior was recorded by overhead webcam, and ants were digitized before and after presentation of the treatment, using two software approaches. The linear regression statistic, r(2) was calculated. Ants initially showed high linear trail integrity (r(2) = 0.75). Within seconds of presentation of the Z,E-alpha-farnesene treatment, the trailing ants showed little or no further evidence of trail following behavior in the vicinity of the pheromone source. These results show that trailing fire ants become disorientated in the presence of large amounts of Z,E-alpha-farnesene. Disrupting fire ant recruitment to resources may have a negative effect on colony size or other effects yet to be determined. This phenomenon was demonstrated recently for the Argentine ant, where trails were disrupted for two weeks by using their formulated trail pheromone, Z-9-hexadecenal. Further research is needed to establish the long term effects and control potential for trail disruption in S. invicta.

Pheromone disruption of Argentine ant trail integrity

USGS Publications Warehouse

Suckling, D.M.; Peck, R.W.; Manning, L.M.; Stringer, L.D.; Cappadonna, J.; El-Sayed, A. M.

2008-01-01

Disruption of Argentine ant trail following and reduced ability to forage (measured by bait location success) was achieved after presentation of an oversupply of trail pheromone, (Z)-9-hexadecenal. Experiments tested single pheromone point sources and dispersion of a formulation in small field plots. Ant walking behavior was recorded and digitized by using video tracking, before and after presentation of trail pheromone. Ants showed changes in three parameters within seconds of treatment: (1) Ants on trails normally showed a unimodal frequency distribution of walking track angles, but this pattern disappeared after presentation of the trail pheromone; (2) ants showed initial high trail integrity on a range of untreated substrates from painted walls to wooden or concrete floors, but this was significantly reduced following presentation of a point source of pheromone; (3) the number of ants in the pheromone-treated area increased over time, as recruitment apparently exceeded departures. To test trail disruption in small outdoor plots, the trail pheromone was formulated with carnuba wax-coated quartz laboratory sand (1 g quartz sand/0.2 g wax/1 mg pheromone). The pheromone formulation, with a half-life of 30 h, was applied by rotary spreader at four rates (0, 2.5, 7.5, and 25 mg pheromone/m2) to 1- and 4-m2 plots in Volcanoes National Park, Hawaii. Ant counts at bait cards in treated plots were significantly reduced compared to controls on the day of treatment, and there was a significant reduction in ant foraging for 2 days. These results show that trail pheromone disruption of Argentine ants is possible, but a much more durable formulation is needed before nest-level impacts can be expected. ?? 2008 Springer Science+Business Media, LLC.

30 CFR 57.12088 - Splicing trailing cables.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Splicing trailing cables. 57.12088 Section 57... Underground Only § 57.12088 Splicing trailing cables. No splice, except a vulcanized splice or its equivalent, shall be made in a trailing cable within 25 feet of the machine unless the machine is equipped with a...

Reduction of background noise induced by wind tunnel jet exit vanes

NASA Technical Reports Server (NTRS)

Martin, R. M.; Brooks, T. F.; Hoad, D. R.

1985-01-01

The NASA-Langley 4 x 7 m wind tunnel develops low frequency flow pulsations at certain velocity ranges during open throat mode operation, affecting the aerodynamics of the flow and degrading the resulting model test data. Triangular vanes attached to the trailing edge of flat steel rails, mounted 10 cm from the inside of the jet exit walls, have been used to reduce this effect; attention is presently given to methods used to reduce the inherent noise generation of the vanes while retaining their pulsation reduction features.

Study on Trailing Edge Ramp of Supercritical Airfoil

DTIC Science & Technology

2016-03-30

7 th Asia-Pacific International Symposium on Aerospace Technology, 25 – 27 November 2015, Cairns Study on Trailing Edge Ramp of Supercritical...China Abstract Trailing edge flow control method could improve the performance of supercritical airfoil with a small modification on the original...airfoil. In this paper, a ramp of 2%~7% chord length is sliced near the trailing edge to improve airfoil performance. The trailing edge ramp is

TRIPPy: Python-based Trailed Source Photometry

NASA Astrophysics Data System (ADS)

Fraser, Wesley C.; Alexandersen, Mike; Schwamb, Megan E.; Marsset, Michael E.; Pike, Rosemary E.; Kavelaars, JJ; Bannister, Michele T.; Benecchi, Susan; Delsanti, Audrey

2016-05-01

TRIPPy (TRailed Image Photometry in Python) uses a pill-shaped aperture, a rectangle described by three parameters (trail length, angle, and radius) to improve photometry of moving sources over that done with circular apertures. It can generate accurate model and trailed point-spread functions from stationary background sources in sidereally tracked images. Appropriate aperture correction provides accurate, unbiased flux measurement. TRIPPy requires numpy, scipy, matplotlib, Astropy (ascl:1304.002), and stsci.numdisplay; emcee (ascl:1303.002) and SExtractor (ascl:1010.064) are optional.

Decoy receptors block TRAIL sensitivity at a supracellular level: the role of stromal cells in controlling tumour TRAIL sensitivity.

PubMed

O'Leary, L; van der Sloot, A M; Reis, C R; Deegan, S; Ryan, A E; Dhami, S P S; Murillo, L S; Cool, R H; Correa de Sampaio, P; Thompson, K; Murphy, G; Quax, W J; Serrano, L; Samali, A; Szegezdi, E

2016-03-10

Tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) is a death ligand cytokine known for its cytotoxic activity against malignantly transformed cells. TRAIL induces cell death through binding to death receptors DR4 and DR5. The inhibitory decoy receptors (DcR1 and DcR2) co-expressed with death receptor 4 (DR4)/DR5 on the same cell can block the transmission of the apoptotic signal. Here, we show that DcRs also regulate TRAIL sensitivity at a supracellular level and thus represent a mechanism by which the microenvironment can diminish tumour TRAIL sensitivity. Mathematical modelling and layered or spheroid stroma-extracellular matrix-tumour cultures were used to model the tumour microenvironment. By engineering TRAIL to escape binding by DcRs, we found that DcRs do not only act in a cell-autonomous or cis-regulatory manner, but also exert trans-cellular regulation originating from stromal cells and affect tumour cells, highlighting the potent inhibitory effect of DcRs in the tumour tissue and the necessity of selective targeting of the two death-inducing TRAIL receptors to maximise efficacy.

Acoustics of Jet Surface Interaction-Scrubbing Noise

NASA Technical Reports Server (NTRS)

Khavaran, Abbas

2014-01-01

Concepts envisioned for the future of civil air transport consist of unconventional propulsion systems in the close proximity of the structure or embedded in the airframe. While such integrated systems are intended to shield noise from community, they also introduce new sources of sound. Sound generation due to interaction of a jet flow past a nearby solid surface is investigated here using the generalized acoustic analogy theory. The analysis applies to the boundary layer noise generated at and near a wall, and excludes the scattered noise component that is produced at the leading or the trailing edge. While compressibility effects are relatively unimportant at very low Mach numbers, frictional heat generation and thermal gradient normal to the surface could play important roles in generation and propagation of sound in high speed jets of practical interest. A general expression is given for the spectral density of the far field sound as governed by the variable density Pridmore-Brown equation. The propagation Greens function is solved numerically for a high aspect-ratio rectangular jet starting with the boundary conditions on the surface and subject to specified mean velocity and temperature profiles between the surface and the observer. It is shown the magnitude of the Greens function decreases with increasing source frequency andor jet temperature. The phase remains constant for a rigid surface, but varies with source location when subject to an impedance type boundary condition. The Greens function in the absence of the surface, and flight effect are also investigated.

Acoustics of Jet Surface Interaction - Scrubbing Noise

NASA Technical Reports Server (NTRS)

Khavaran, Abbas

2014-01-01

Concepts envisioned for the future of civil air transport consist of unconventional propulsion systems in the close proximity to the structure or embedded in the airframe. While such integrated systems are intended to shield noise from the community, they also introduce new sources of sound. Sound generation due to interaction of a jet flow past a nearby solid surface is investigated here using the generalized acoustic analogy theory. The analysis applies to the boundary layer noise generated at and near a wall, and excludes the scattered noise component that is produced at the leading or the trailing edge. While compressibility effects are relatively unimportant at very low Mach numbers, frictional heat generation and thermal gradient normal to the surface could play important roles in generation and propagation of sound in high speed jets of practical interest. A general expression is given for the spectral density of the far field sound as governed by the variable density Pridmore-Brown equation. The propagation Green's function is solved numerically for a high aspect-ratio rectangular jet starting with the boundary conditions on the surface and subject to specified mean velocity and temperature profiles between the surface and the observer. It is shown the magnitude of the Green's function decreases with increasing source frequency and/or jet temperature. The phase remains constant for a rigid surface, but varies with source location when subject to an impedance type boundary condition. The Green's function in the absence of the surface, and flight effects are also investigated

30 CFR 75.604 - Permanent splicing of trailing cables.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Permanent splicing of trailing cables. 75.604... SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Trailing Cables § 75.604 Permanent splicing of trailing cables. [Statutory Provisions] When permanent splices in trailing cables are made...

Hydrodynamic Trails Produced by Daphnia: Size and Energetics

PubMed Central

Wickramarathna, Lalith N.; Noss, Christian; Lorke, Andreas

2014-01-01

This study focuses on quantifying hydrodynamic trails produced by freely swimming zooplankton. We combined volumetric tracking of swimming trajectories with planar observations of the flow field induced by Daphnia of different size and swimming in different patterns. Spatial extension of the planar flow field along the trajectories was used to interrogate the dimensions (length and volume) and energetics (dissipation rate of kinetic energy and total dissipated power) of the trails. Our findings demonstrate that neither swimming pattern nor size of the organisms affect the trail width or the dissipation rate. However, we found that the trail volume increases with increasing organism size and swimming velocity, more precisely the trail volume is proportional to the third power of Reynolds number. This increase furthermore results in significantly enhanced total dissipated power at higher Reynolds number. The biggest trail volume observed corresponds to about 500 times the body volume of the largest daphnids. Trail-averaged viscous dissipation rate of the swimming daphnids vary in the range of to and the observed magnitudes of total dissipated power between and , respectively. Among other zooplankton species, daphnids display the highest total dissipated power in their trails. These findings are discussed in the context of fluid mixing and transport by organisms swimming at intermediate Reynolds numbers. PMID:24671019

A mixed-modes approach for estimating hiking on trails through diverse forest landscapes: the case of the Appalachian Trail

Treesearch

Stanley J. Zarnoch; J.M. Bowker; H. Ken Cordell

2011-01-01

Many hiking trails traverse the forests and public lands across North America. It has therefore become important for federal management to gain an understanding of total use on these trails. However, there has never been a formal attempt to estimate hiking on these long, backcountry trails. This paper presents an approach that utilizes two survey instruments (exit-site...

Chemical trail marking and following by caterpillars ofMalacosoma neustria.

PubMed

Peterson, S C

1988-03-01

Chemical trail marking and following by gregarious caterpillars,Malacosoma neustria L. (Lepidoptera: Lasiocampidae), was studied in the laboratory. As in other species ofMalacosoma, larvae deposit a trail pheromone from a sternal secretory site when searching the host for food. Larvae in the vanguard of foraging columns establish chemical trails as they explore new territory. Marking behavior diminishes as successive unfed foragers utilize the trail. These exploratory trails are subsequently overmarked by fed larvae returning to the tent. Other foragers follow the trails of fed larvae in preference to trails of unfed larvae. Thus, like the eastern tent caterpillar,M. americanum, successful foragers ofM. neustria recruit colony-mates to feeding sites. The chemical activity of both recruitment and exploratory trails degrades slowly, suggesting that the trail pheromone ofM. neustria is a nonvolatile substance. Caterpillars ofM. neustria readily follow the nonvolatile trail pheromone which has been identified fromM. americanum, 5β-cholestane-3,24-dione.

30 CFR 75.603 - Temporary splice of trailing cable.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Temporary splice of trailing cable. 75.603... SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Trailing Cables § 75.603 Temporary splice of trailing cable. [Statutory Provision] One temporary splice may be made in any trailing cable...

30 CFR 77.602 - Permanent splicing of trailing cables.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Permanent splicing of trailing cables. 77.602... COAL MINES Trailing Cables § 77.602 Permanent splicing of trailing cables. When permanent splices in trailing cables are made, they shall be: (a) Mechanically strong with adequate electrical conductivity; (b...

Wicket gate trailing-edge blowing: A method for improving off-design hydroturbine performance by adjusting the runner inlet swirl angle

NASA Astrophysics Data System (ADS)

Lewis, B. J.; Cimbala, J. M.; Wouden, A. M.

2014-03-01

At their best efficiency point (BEP), hydroturbines operate at very high efficiency. However, with the ever-increasing penetration of alternative electricity generation, it has become common to operate hydroturbines at off-design conditions in order to maintain stability in the electric power grid. This paper demonstrates a method for improving hydroturbine performance during off-design operation by injecting water through slots at the trailing edges of the wicket gates. The injected water causes a change in bulk flow direction at the inlet of the runner. This change in flow angle from the wicket gate trailing-edge jets provides the capability of independently varying the flow rate and swirl angle through the runner, which in current designs are both determined by the wicket gate opening angle. When properly tuned, altering the flow angle results in a significant improvement in turbine efficiency during off-design operation.

Impact of Fluidic Chevrons on Jet Noise

NASA Technical Reports Server (NTRS)

Henderson, Brenda S.; Kinzie, Kevin W.; Whitmire, Julia; Abeysinghe, Amal

2005-01-01

The impact of alternating fluidic core chevrons on the production of jet noise is investigated. Core nozzles for a representative 1/9th scale, bypass ratio 5 model system were manufactured with slots cut near the trailing edges to allow for air injection into the core and fan streams. The injectors followed an alternating pattern around the nozzle perimeter so that the injection alternated between injection into the core stream and injection into the fan stream. For the takeoff condition and a forward flight Mach number of 0.10, the overall sound pressure levels at the peak jet noise angle decrease with increasing injection pressure. Sound pressure levels increase for observation angles less than 110o at higher injection pressures due to increases in high frequency noise. Greater increases in high frequency noise are observed when the number of injectors increases from 8 to 12. When the forward flight Mach number is increased to 0.28, jet noise reduction (relative to the baseline) is observed at aft angles for increasing injection pressure while significant increases in jet noise are observed at forward observation angles due to substantial acoustic radiation at high frequencies. A comparison between inflow and alternating injectors shows that, for equal mass injection rates, the inflow nozzle produces greater low frequency noise reduction (relative to the baseline) than the alternating injectors at 90o and aft observation angles and a forward flight Mach number of 0.28. Preliminary computational fluid dynamic simulations indicate that the spatial decay rate of the hot potential core flow is less for the inflow nozzle than for the alternating nozzles which indicates that gentle mixing may be preferred over sever mixing when fluidic chevrons are used for jet noise reduction.

Cold PSM, but not TRAIL, triggers autophagic cell death: A therapeutic advantage of PSM over TRAIL.

PubMed

Ito, Tomohisa; Ando, Takashi; Suzuki-Karasaki, Miki; Tokunaga, Tomohiko; Yoshida, Yukihiro; Ochiai, Toyoko; Tokuhashi, Yasuaki; Suzuki-Karasaki, Yoshihiro

2018-05-21

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and cold plasma-stimulated medium (PSM) are promising novel anticancer tools due to their strong anticancer activities and high tumor-selectivity. The present study demonstrated that PSM and TRAIL may trigger autophagy in human malignant melanoma and osteosarcoma cells. Live-cell imaging revealed that even under nutritional and stress-free conditions, these cells possessed a substantial level of autophagosomes, which were localized in the cytoplasm separately from tubular mitochondria. In response to cytotoxic levels of PSM, the mitochondria became highly fragmented, and aggregated and colocalized with the autophagosomes. The cytotoxic effects of PSM were suppressed in response to various pharmacological autophagy inhibitors, including 3-methyladenine (3-MA) and bafilomycin A1, thus indicating the induction of autophagic cell death (ACD). Lethal levels of PSM also resulted in non-apoptotic, non-autophagic cell death in a reactive oxygen species-dependent manner under certain circumstances. Furthermore, TRAIL exhibited only a modest cytotoxicity toward these tumor cells, and did not induce ACD and mitochondrial aberration. The combined use of TRAIL and subtoxic concentrations of 3-MA resulted in decreased basal autophagy, increased mitochondrial aberration, colocalization with autophagosomes and apoptosis. These results indicated that PSM may induce ACD, whereas TRAIL may trigger cytoprotective autophagy that compromises apoptosis. To the best of our knowledge, the present study is the first to demonstrate that PSM can induce ACD in human cancer cells. These findings provide a rationale for the advantage of PSM over TRAIL in the destruction of apoptosis-resistant melanoma and osteosarcoma cells.

Identification of TRAIL-inducing compounds highlights small molecule ONC201/TIC10 as a unique anti-cancer agent that activates the TRAIL pathway.

PubMed

Allen, Joshua E; Krigsfeld, Gabriel; Patel, Luv; Mayes, Patrick A; Dicker, David T; Wu, Gen Sheng; El-Deiry, Wafik S

2015-05-01

We previously reported the identification of ONC201/TIC10, a novel small molecule inducer of the human TRAIL gene that improves efficacy-limiting properties of recombinant TRAIL and is in clinical trials in advanced cancers based on its promising safety and antitumor efficacy in several preclinical models. We performed a high throughput luciferase reporter screen using the NCI Diversity Set II to identify TRAIL-inducing compounds. Small molecule-mediated induction of TRAIL reporter activity was relatively modest and the majority of the hit compounds induced low levels of TRAIL upregulation. Among the candidate TRAIL-inducing compounds, TIC9 and ONC201/TIC10 induced sustained TRAIL upregulation and apoptosis in tumor cells in vitro and in vivo. However, ONC201/TIC10 potentiated tumor cell death while sparing normal cells, unlike TIC9, and lacked genotoxicity in normal fibroblasts. Investigating the effects of TRAIL-inducing compounds on cell signaling pathways revealed that TIC9 and ONC201/TIC10, which are the most potent inducers of cell death, exclusively activate Foxo3a through inactivation of Akt/ERK to upregulate TRAIL and its pro-apoptotic death receptor DR5. These studies reveal the selective activity of ONC201/TIC10 that led to its selection as a lead compound for this novel class of antitumor agents and suggest that ONC201/TIC10 is a unique inducer of the TRAIL pathway through its concomitant regulation of the TRAIL ligand and its death receptor DR5.

Nature Trails, Braille Trails, Foot Paths, Fragrance Gardens, Touch Museums for the Blind; Policy Statement.

ERIC Educational Resources Information Center

American Foundation for the Blind, New York, NY.

The policy statement by the American Foundation for the Blind deals with nature trails, braille trails, foot paths, fragrance gardens, and touch museums for the blind. It is stated that the foundation approves of services such as provision of tape recorded guides and planting of fragrant shrubs which would benefit all users while recognizing…

30 CFR 57.12003 - Trailing cable overload protection.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Trailing cable overload protection. 57.12003... Electricity Surface and Underground § 57.12003 Trailing cable overload protection. Individual overload protection or short circuit protection shall be provided for the trailing cables of mobile equipment. ...

Assessing soil erosion on trails: A comparison of techniques

Treesearch

Mark C. Jewell; William E. Hammitt

2000-01-01

Reports of trail degradation have been increasing in different wildernesses. This impact has become a common concern among managers. Deteriorating tread conditions of trails are increasing, as is concern at protected areas worldwide. In order to make objective and timely trail resource decisions, managers need to have effective and efficient methods of assessing trail...

Jet Surface Interaction Noise in a High Aspect Ratio Rectangular Exhaust

NASA Technical Reports Server (NTRS)

Khavaran, Abbas

2017-01-01

A physics-based prediction model is employed to simulate jet surface interaction (JSI) noise in a transversely sheared jet exhaust. The methodology finds application in jets with a high aspect ratio (AR) rectangular exhaust in the proximity of a flat surface. Two component spectra are simulated: (i) mixing/scrubbing noise; (ii) trailing edge noise--and are superimposed to obtain the far field exhaust noise on either side of a nearby surface. This document describes the necessary input parameters (including mean flow and turbulence information for the nozzle exhaust of interest) that should be prepared in order to initiate the simulation for each noise component. Sample input/output files in connection with an 8:1 aspect ratio rectangular exhaust at Mach 0.98 near a rigid surface are described. Jet noise spectra are examined below at operating conditions listed in Table IV. Individual noise components, designated as Scrubbing Noise and Trailing Edge Noise, are presented and their sum Total Noise (Analysis) is compared with Measurement (Refs. 8 and 9) at selective number of observer polar angles at azimuth f = 90deg. Results are presented on an arc R = 17.80-ft (i.e., R = 100Deq) on both sides of a nearby surface. Although the predicted TE noise component is symmetric with respect to the edge due to symmetry in the propagator, measurements for the majority of cases are not quite symmetric and exhibit a slightly larger peak on the reflected side of the surface. Turbulent mixing/scrubbing noise component has a greater presence on the reflected side, as expected. Figure 13 to Figure 18 show that the peak in the predicted TE component could differ from measurements by as much as 4 dB due to lack of symmetry in measured data, however, the general trend is in agreement with data across the three Mach numbers. The overall sound pressure level (OASPL) associated with the TE noise component follows a U5 velocity scaling in the current modeling (Ref. 4). Directivity

Vortex shedding from a blunt trailing edge with equal and unequal external mean velocities

NASA Technical Reports Server (NTRS)

Brinich, P. F.; Boldman, D. R.; Goldstein, M. E.

1975-01-01

A flow visualization study showed that strong Karman vortices are developed behind the blunt trailing edge of a plate when the free stream velocities over both surfaces are equal. These vortices tend to disappear when the surface velocities are unequal. This observation provided an explanation for the occurrence and disappearance of the lip noise often present in coaxial jets. Vortex formation and lip noise occurred at a Strouhal number of about 0.2 based on the lip thickness and the average of the external steady-state velocities. Results from theoretical calculations of the vortex formation, based on an inviscid, incompressible analysis of the motion of point vortices, were in good agreement with the experimental observations.

Airbag Trails

NASA Technical Reports Server (NTRS)

2004-01-01

This segment of the first color image from the panoramic camera on the Mars Exploration Rover Spirit shows the rover's airbag trails. These depressions in the soil were made when the airbags were deflated and retracted after landing.

30 CFR 57.12038 - Attachment of trailing cables.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Attachment of trailing cables. 57.12038 Section 57.12038 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Electricity Surface and Underground § 57.12038 Attachment of trailing cables. Trailing cables shall be...

Condensation model for the ESBWR passive condensers

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

Revankar, S. T.; Zhou, W.; Wolf, B.

2012-07-01

In the General Electric's Economic simplified boiling water reactor (GE-ESBWR) the passive containment cooling system (PCCS) plays a major role in containment pressure control in case of an loss of coolant accident. The PCCS condenser must be able to remove sufficient energy from the reactor containment to prevent containment from exceeding its design pressure following a design basis accident. There are three PCCS condensation modes depending on the containment pressurization due to coolant discharge; complete condensation, cyclic venting and flow through mode. The present work reviews the models and presents model predictive capability along with comparison with existing data frommore » separate effects test. The condensation models in thermal hydraulics code RELAP5 are also assessed to examine its application to various flow modes of condensation. The default model in the code predicts complete condensation well, and basically is Nusselt solution. The UCB model predicts through flow well. None of condensation model in RELAP5 predict complete condensation, cyclic venting, and through flow condensation consistently. New condensation correlations are given that accurately predict all three modes of PCCS condensation. (authors)« less

Effects of homogeneous condensation in compressible flows: Ludwieg-tube experiments and simulations

NASA Astrophysics Data System (ADS)

Luo, Xisheng; Lamanna, Grazia; Holten, A. P. C.; van Dongen, M. E. H.

Effects of homogeneous nucleation and subsequent droplet growth in compressible flows in humid nitrogen are investigated numerically and experimentally. A Ludwieg tube is employed to produce expansion flows. Corresponding to different configurations, three types of experiment are carried out in such a tube. First, the phase transition in a strong unsteady expansion wave is investigated to demonstrate the mutual interaction between the unsteady flow and the condensation process and also the formation of condensation-induced shock waves. The role of condensation-induced shocks in the gradual transition from a frozen initial structure to an equilibrium structure is explained. Second, the condensing flow in a slender supersonic nozzle G2 is considered. Particular attention is given to condensation-induced oscillations and to the transition from symmetrical mode-1 oscillations to asymmetrical mode-2 oscillations in a starting nozzle flow, as first observed by Adam & Schnerr. The transition is also found numerically, but the amplitude, frequency and transition time are not yet well predicted. Third, a sharp-edged obstacle is placed in the tube to generate a starting vortex. Condensation in the vortex is found. Owing to the release of latent heat of condensation, an increase in the pressure and temperature in the vortex core is observed. Condensation-induced shock waves are found, for a sufficiently high initial saturation ratio, which interact with the starting vortex, resulting in a very complex flow. As time proceeds, a subsonic or transonic free jet is formed downstream of the sharp-edged obstacle, which becomes oscillatory for a relatively high main-flow velocity and for a sufficiently high humidity.

Trails at LANL - Public Meeting and Forum - July 26, 2016

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

Pava, Daniel Seth

2016-07-26

These are the slides of a meeting about trails at Los Alamos National Laboratory. The meeting goals are the folllowing: to inform and educate citizens about LANL trails management issues that include resource protection, safety, security and trails etiquette; to explain how and why LANL trails can be closed and reopened; and to understand your concerns and ideas about LANL trails use.

Mechanism of trail following by the arboreal termite Nasutitermes corniger (Isoptera: Termitidae).

PubMed

Gazai, Vinícius; Bailez, Omar; Viana-Bailez, Ana Maria

2014-01-01

In this study, we investigated the mechanisms used by the arboreal termite Nasutitermes corniger (Motschulsky, 1855) to follow trails from the nest to sources of food. A plate containing one of seven trail types was used to connect an artificial nest of N. corniger with an artificial foraging arena. The trail types were: termite trail; paraffined termite trail; trail made of paraffin; rectal fluid extract trail; sternal gland extract trail; feces extract trail; and solvent trail (control). In each test, the time was recorded from the start of the test until the occurrence of trail following, at which point the number of termites that followed the trail for least 5 cm in the first 3 min of observation was recorded. The delay for termites initiating trail following along the termite trail was lower (0.55 ± 0.16 min) than in the trails of sternal gland extract (1.05 ± 0.08 min) and trails of termite feces extract (1.57 ± 0.21 min) (F(2), (48) = 22.59, P < 0.001). The number of termites that followed the termite trail was greater (207.3 ± 17.3) than the number that followed the trail of termite feces extract (102.5 ± 9.4) or sternal gland extract (36, 9 ± 1.6) (F(2), (48) = 174.34, P < 0.001). Therefore, feces on the trail may play an important role alongside sternal gland pheromones in increasing the persistence of the trail.

36 CFR 7.100 - Appalachian National Scenic Trail.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Trail. 7.100 Section 7.100 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR SPECIAL REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.100 Appalachian National Scenic Trail...? (1) You may cross the Appalachian National Scenic Trail corridor by using established, State-approved...

Experimental and Analytical Studies of Shielding Concepts for Point Sources and Jet Noise.

DTIC Science & Technology

1983-05-01

proximnity of the turbulent jet flow to the The Spectral Dynamics DSP 360 is a two channel real time analyzer incor- shielding surface, the edge will interact...However, this is achieved with a very long shield length equal to 190 unorthodox configurations. The emphasis is placed on the concept, times the slit...16 dB/dec. .Vn With this solid-gaseous combination, a 10 0 diameter shield of length 14 DVf =- sin 0 with a burner attached to the trailing edge

17 CFR 37.205 - Audit trail.

Code of Federal Regulations, 2014 CFR

2014-04-01

... trading; and (iv) Identification of each account to which fills are allocated. (3) Electronic analysis capability. A swap execution facility's audit trail program shall include electronic analysis capability with respect to all audit trail data in the transaction history database. Such electronic analysis capability...

Hydrodynamic trails produced by Daphnia: size and energetics.

PubMed

Wickramarathna, Lalith N; Noss, Christian; Lorke, Andreas

2014-01-01

This study focuses on quantifying hydrodynamic trails produced by freely swimming zooplankton. We combined volumetric tracking of swimming trajectories with planar observations of the flow field induced by Daphnia of different size and swimming in different patterns. Spatial extension of the planar flow field along the trajectories was used to interrogate the dimensions (length and volume) and energetics (dissipation rate of kinetic energy and total dissipated power) of the trails. Our findings demonstrate that neither swimming pattern nor size of the organisms affect the trail width or the dissipation rate. However, we found that the trail volume increases with increasing organism size and swimming velocity, more precisely the trail volume is proportional to the third power of Reynolds number. This increase furthermore results in significantly enhanced total dissipated power at higher Reynolds number. The biggest trail volume observed corresponds to about 500 times the body volume of the largest daphnids. Trail-averaged viscous dissipation rate of the swimming daphnids vary in the range of 1.8 x 10(-6) W/kg to 3.4 x 10(-6) W/kg and the observed magnitudes of total dissipated power between 1.3 x 10(-9) W and 1 x 10(-8) W, respectively. Among other zooplankton species, daphnids display the highest total dissipated power in their trails. These findings are discussed in the context of fluid mixing and transport by organisms swimming at intermediate Reynolds numbers.

The Effect of Break Edge Configuration on the Aerodynamics of Anti-Ice Jet Flow

NASA Astrophysics Data System (ADS)

Tatar, V.; Yildizay, H.; Aras, H.

2015-05-01

One of the components of a turboprop gas turbine engine is the Front Bearing Structure (FBS) which leads air into the compressor. FBS directly encounters with ambient air, as a consequence ice accretion may occur on its static vanes. There are several aerodynamic parameters which should be considered in the design of anti-icing system of FBS, such as diameter, position, exit angle of discharge holes, etc. This research focuses on the effects of break edge configuration over anti-ice jet flow. Break edge operation is a process which is applied to the hole in order to avoid sharp edges which cause high stress concentration. Numerical analyses and flow visualization test have been conducted. Four different break edge configurations were used for this investigation; without break edge, 0.35xD, 74xD, 0.87xD. Three mainstream flow conditions at the inlet of the channel are defined; 10m/s, 20 m/s and 40 m/s. Shear stresses are extracted from numerical analyses near the trailing edge of pressure surface where ice may occur under icing conditions. A specific flow visualization method was used for the experimental study. Vane surface near the trailing edge was dyed and thinner was injected into anti-ice jet flow in order to remove dye from the vane surface. Hence, film effect on the surface could be computed for each testing condition. Thickness of the dye removal area of each case was examined. The results show noticeable effects of break edge operation on jet flow, and the air film effectiveness decreases when mainstream inlet velocity decreases.

TRIPPy: Trailed Image Photometry in Python

NASA Astrophysics Data System (ADS)

Fraser, Wesley; Alexandersen, Mike; Schwamb, Megan E.; Marsset, Michaël; Pike, Rosemary E.; Kavelaars, J. J.; Bannister, Michele T.; Benecchi, Susan; Delsanti, Audrey

2016-06-01

Photometry of moving sources typically suffers from a reduced signal-to-noise ratio (S/N) or flux measurements biased to incorrect low values through the use of circular apertures. To address this issue, we present the software package, TRIPPy: TRailed Image Photometry in Python. TRIPPy introduces the pill aperture, which is the natural extension of the circular aperture appropriate for linearly trailed sources. The pill shape is a rectangle with two semicircular end-caps and is described by three parameters, the trail length and angle, and the radius. The TRIPPy software package also includes a new technique to generate accurate model point-spread functions (PSFs) and trailed PSFs (TSFs) from stationary background sources in sidereally tracked images. The TSF is merely the convolution of the model PSF, which consists of a moffat profile, and super-sampled lookup table. From the TSF, accurate pill aperture corrections can be estimated as a function of pill radius with an accuracy of 10 mmag for highly trailed sources. Analogous to the use of small circular apertures and associated aperture corrections, small radius pill apertures can be used to preserve S/Ns of low flux sources, with appropriate aperture correction applied to provide an accurate, unbiased flux measurement at all S/Ns.

Computational Evaluation of the Steady and Pulsed Jet Effects on the Performance of a Circulation Control Wing Section

NASA Technical Reports Server (NTRS)

Liu, Yi; Sankar, Lakshmi N.; Englar, Robert J.; Ahuja, Krishan K.; Gaeta, R.

2005-01-01

Circulation Control technology is a very effective way of achieving high lift forces required by aircraft during take-off and landing. This technology can also directly control the flow field over the wing. Compared to a conventional high-lift system, a Circulation Control Wing (CCW) can generate comparable or higher lift forces during take-off/landing with fewer or no moving parts and much less complexity. In this work, an unsteady three-dimensional Navier-Stokes analysis procedure has been developed and applied to Circulation Control Wing configurations. The effects of 2-D steady jets and 2-D pulsed jets on the aerodynamic performance of CCW airfoils have been investigated. It is found that a steady jet can generate very high lift at zero angle of attack without stall, and that a small amount of blowing can eliminate vortex shedding at the trailing edge, a potential noise source. It is also found that a pulsed jet can achieve the same high lift as a steady jet at lower mass flow rates, especially at a high frequency, and that the Strouhal number has a more dominant effect on the pulsed jet performance than just the frequency or the free-stream velocity.

Trail impact monitoring in Rocky Mountain National Park, USA

NASA Astrophysics Data System (ADS)

Svajda, J.; Korony, S.; Brighton, I.; Esser, S.; Ciapala, S.

2016-01-01

This paper examines impacts of increased visitation leading to human trampling of vegetation and soil along several trails in Rocky Mountain National Park (RMNP) to understand how abiotic factors and level of use can influence trail conditions. RMNP is one of the most visited national parks in the USA, with 3.3 million visitors in 2012 across 1075 km2 and 571 km of hiking trails. 95 % of the park is designated wilderness, making the balance between preservation and visitor use challenging. This research involves the application of trail condition assessments to 56 km of trails to determine prevailing factors and what, if any, connection between them exist. The study looked at a variety of inventory and impact indicators and standards to determine their importance and to develop a baseline condition of trails. The data can be used for future comparison and evaluation of development trends. We found that trail widening (mean trail width 88.9 cm) and soil loss (cross-sectional area 172.7 cm2) are the most visible effects of trail degradation. Further statistical analyses of data identified the role and influence of various factors (e.g., use level and topography). Insights into the influence of these factors can lead to the selection of appropriate management measures to avoid or minimize negative consequences from increased visitation.

Trail impact monitoring in Rocky Mountain National Park, USA

NASA Astrophysics Data System (ADS)

Svajda, J.; Korony, S.; Brighton, I.; Esser, S.; Ciapala, S.

2015-11-01

This paper examines impacts of increased visitation leading to human trampling of vegetation and soil along several trails in Rocky Mountain National Park (RMNP) to understand how abiotic factors and level of use can influence trail conditions. RMNP is one of the most visited national parks in the USA with 3.3 million visitors in 2012 across 1075 km2 and 571 km of hiking trails. 95 % of the park is designated wilderness making the balance between preservation and visitor use challenging. This research involves the application of trail condition assessments to 56 km of trails to determine prevailing factors and what, if any, connection between them exist. The study looked at a variety of inventory and impact indicators and standards to determine their importance and to develop a baseline condition of trails. The data can be used for future comparison and evaluation of development trends. We found that trail widening (mean trail width 88.9 cm) and soil loss (cross sectional area 172.7 cm2) are the most visible effects of trail degradation. Further statistical analyses of data identified the role and influence of various factors (e.g. use level and topography). Insights into the influence of these factors can lead to the selection of appropriate management measures to avoid or minimize negative consequences from increased visitation.

Use and Nonuse of a Rail Trail Conversion for Physical Activity: Implications for Promoting Trail Use

ERIC Educational Resources Information Center

Price, Anna E.; Reed, Julian A.

2014-01-01

Background: There is limited research examining both use and nonuse of trails for physical activity. Purpose: Such research might enable health educators to better promote physical activity on trails.Methods:We used random digit dialing methods to survey 726 respondents in 2012. Results: The majority (75.1%) of respondents reported not using the…

49 CFR 236.776 - Movement, trailing.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Movement, trailing. 236.776 Section 236.776 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Movement, trailing. The movement of a train over the points of a switch which face in the direction in...

Flow of Combustion Products Containing Condensed-Phase Particles over a Recessed Vectorable Jet Nozzle

NASA Astrophysics Data System (ADS)

Volkov, K. N.; Denisikhin, S. V.; Emel'yanov, V. N.; Teterina, I. V.

2017-09-01

The flow of combustion products containing condensed-phase particles over the recessed vectorable nozzle of a solid-propellant rocket motor was investigated with the use of the Reynolds-averaged Navier-Stokes equations, equations of the k-ɛ model of turbulence, and the Lagrange approach. The fields of flows of combustion products and the mechanical trajectories of condensed-phase particles in the charge channel, the prenozzle space, and the nozzle unit of this motor were calculated for different angles of swing of the nozzle. The formation of vortices in the gas flow in the neighborhood of the downstream cover of the nozzle and their influence on the movement of particles different in size were considered.

33 CFR 117.401 - Trail Creek.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Trail Creek. 117.401 Section 117.401 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Indiana § 117.401 Trail Creek. (a) The draw of the Franklin...

30 CFR 75.601 - Short circuit protection of trailing cables.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Short circuit protection of trailing cables. 75... MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Trailing Cables § 75.601 Short circuit protection of trailing cables. [Statutory Provisions] Short circuit protection for trailing cables...

30 CFR 75.605 - Clamping of trailing cables to equipment.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Clamping of trailing cables to equipment. 75... MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Trailing Cables § 75.605 Clamping of trailing cables to equipment. [Statutory Provisions] Trailing cables shall be clamped to...

Multiuse trail intersection safety analysis: A crowdsourced data perspective.

PubMed

Jestico, Ben; Nelson, Trisalyn A; Potter, Jason; Winters, Meghan

2017-06-01

Real and perceived concerns about cycling safety are a barrier to increased ridership in many cities. Many people prefer to bike on facilities separated from motor vehicles, such as multiuse trails. However, due to underreporting, cities lack data on bike collisions, especially along greenways and multiuse paths. We used a crowdsourced cycling incident dataset (2005-2016) from BikeMaps.org for the Capital Regional District (CRD), BC, Canada. Our goal was to identify design characteristics associated with unsafe intersections between multiuse trails and roads. 92.8% of mapped incidents occurred between 2014 and 2016. We extracted both collision and near miss incidents at intersections from BikeMaps.org. We conducted site observations at 32 intersections where a major multiuse trail intersected with roads. We compared attributes of reported incidents at multiuse trail-road intersections to those at road-road intersections. We then used negative binomial regression to model the relationship between the number of incidents and the infrastructure characteristics at multiuse trail-road intersections. We found a higher proportion of collisions (38%, or 17/45 total reports) at multiuse trail-road intersections compared to road-road intersections (23%, or 62/268 total reports). A higher proportion of incidents resulted in an injury at multiuse trail-road intersections compared to road-road intersections (33% versus 15%). Cycling volumes, vehicle volumes, and trail sight distance were all associated with incident frequency at multiuse trail-road intersections. Supplementing traditional crash records with crowdsourced cycling incident data provides valuable evidence on cycling safety at intersections between multiuse trails and roads, and more generally, when conflicts occur between diverse transportation modes. Copyright © 2017. Published by Elsevier Ltd.

Atmospheric motion investigation for vapor trails and radio meteors

NASA Technical Reports Server (NTRS)

Bedinger, J.

1973-01-01

The dynamics are investigated of the lower thermosphere through comparison of optical observations of motions of ejected vapor trails with radar observations of motions of ionized meteor trails. In particular, the winds obtained from a series of vapor trail observations which occurred at Wallops Island, Virginia during the night of 14-15 December 1970 are to be compared with wind data deduced from radar observations of meteor trails during the same period. The comparison of these data is considered important for two reasons. First, the most widely used methods of measuring winds in the lower thermosphere are the vapor trails and the radar meteors. However, the two techniques differ markedly and the resultant sets of data have been analyzed and presented in different formats. Secondly, and possibly of greater immediate concern is the fact that the radar meteor method appears to be an appropriate approach to the synoptic measurement of winds. During the night of 14-15 December 1970, five vapor trails were ejected from Nike Apache rockets over Wallops Island, Virginia from 2208 EST through 0627 EST. The wind data which were obtained from these trails are presented, and features of the wind profiles which relate to the radar meteor trails results are discussed.

30 CFR 77.603 - Clamping of trailing cables to equipment.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Clamping of trailing cables to equipment. 77.603 Section 77.603 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL... UNDERGROUND COAL MINES Trailing Cables § 77.603 Clamping of trailing cables to equipment. Trailing cables...

Transonic Drag Reduction Through Trailing-Edge Blowing on the FAST-MAC Circulation Control Model

NASA Technical Reports Server (NTRS)

Chan, David T.; Jones, Gregory S.; Milholen, William E., II; Goodliff, Scott L.

2017-01-01

A third wind tunnel test of the FAST-MAC circulation control semi-span model was completed in the National Transonic Facility at the NASA Langley Research Center where the model was configured for transonic testing of the cruise configuration with 0deg flap detection to determine the potential for transonic drag reduction with the circulation control blowing. The model allowed independent control of four circulation control plenums producing a high momentum jet from a blowing slot near the wing trailing edge that was directed over a 15% chord simple-hinged ap. Recent upgrades to transonic semi-span flow control testing at the NTF have demonstrated an improvement to overall data repeatability, particularly for the drag measurement, that allows for increased confidence in the data results. The static thrust generated by the blowing slot was removed from the wind-on data using force and moment balance data from wind-o thrust tares. This paper discusses the impact of the trailing-edge blowing to the transonic aerodynamics of the FAST-MAC model in the cruise configuration, where at flight Reynolds numbers, the thrust-removed corrected data showed that an overall drag reduction and increased aerodynamic efficiency was realized as a consequence of the blowing.

Experimental evaluation of the certification-trail method

NASA Technical Reports Server (NTRS)

Sullivan, Gregory F.; Wilson, Dwight S.; Masson, Gerald M.; Itoh, Mamoru; Smith, Warren W.; Kay, Jonathan S.

1993-01-01

Certification trails are a recently introduced and promising approach to fault-detection and fault-tolerance. A comprehensive attempt to assess experimentally the performance and overall value of the method is reported. The method is applied to algorithms for the following problems: huffman tree, shortest path, minimum spanning tree, sorting, and convex hull. Our results reveal many cases in which an approach using certification-trails allows for significantly faster overall program execution time than a basic time redundancy-approach. Algorithms for the answer-validation problem for abstract data types were also examined. This kind of problem provides a basis for applying the certification-trail method to wide classes of algorithms. Answer-validation solutions for two types of priority queues were implemented and analyzed. In both cases, the algorithm which performs answer-validation is substantially faster than the original algorithm for computing the answer. Next, a probabilistic model and analysis which enables comparison between the certification-trail method and the time-redundancy approach were presented. The analysis reveals some substantial and sometimes surprising advantages for ther certification-trail method. Finally, the work our group performed on the design and implementation of fault injection testbeds for experimental analysis of the certification trail technique is discussed. This work employs two distinct methodologies, software fault injection (modification of instruction, data, and stack segments of programs on a Sun Sparcstation ELC and on an IBM 386 PC) and hardware fault injection (control, address, and data lines of a Motorola MC68000-based target system pulsed at logical zero/one values). Our results indicate the viability of the certification trail technique. It is also believed that the tools developed provide a solid base for additional exploration.

Appalachian National Scenic Trail pilot survey

Treesearch

Stan Zarnoch; Michael Bowker; Ken Cordell; Matt Owens; Gary T. Green; Allison Ginn

2011-01-01

Visitation statistics on the Appalachian National Scenic Trail (AT) are important for management and Federal Government reporting purposes. However, no survey methodology has been developed to obtain accurate trailwide estimates over linear trails that traverse many hundreds of back-country miles. This research develops a stratified random survey design which utilizes...

Making Sense of Audit Trail Data

ERIC Educational Resources Information Center

Kennedy, Gregor E.; Judd, Terry S.

2004-01-01

In this paper we argue that the use of audit trail data for research and evaluation purposes has attracted scepticism due to real and perceived difficulties associated with the data's interpretation. We suggest that educational technology researchers and evaluators need to better understand how audit trail data can be processed and analysed…

Na Ala Hele (Trails for Walking).

ERIC Educational Resources Information Center

Hawaii State Dept. of Planning and Economic Development, Honolulu.

This proposal for the development of a system of administering hiking trails in the state of Hawaii when such trails would involve various public and private jurisdictions emphasizes three elements: (a) proposing means of administration involving multiple jurisdictions; (b) demonstrating by means of a proposed project on the west coast of the Big…

Dynamics and mixing mechanism of transverse jet injection into a supersonic combustor with cavity flameholder

NASA Astrophysics Data System (ADS)

Liu, Chaoyang; Zhao, Yanhui; Wang, Zhenguo; Wang, Hongbo; Sun, Mingbo

2017-07-01

The interaction between sonic transverse jet and supersonic crossflow coupled with a cavity flameholder is investigated using large eddy simulation (LES), where the compressible flow dynamics and fuel mixing mechanism are analyzed emphatically. An adaptive central-upwind 6th-order weighted essentially non-oscillatory (WENO-CU6) scheme along with multi-threaded and multi-process MPI/OpenMP parallel is adopted to improve the accuracy and parallel efficiency of the solver. This simulation aims to reproduce the flow conditions in the experiment, and the results show fairly good agreement with the experimental data for distributions of streamwise and normal velocity components. Instantaneous structures such as the shock, large scale vortices and recirculation zone are identified, and their spatial deformation and temporal evolution are presented to reveal the effect on the subsequent mixing. Then some time-averaged and statistical results are obtained to explain the interesting phenomenon observed in the experiment, that there are two pairs of counter-rotating streamwise vortices existing in and above the cavity with the same rotation direction. The above pair is induced by the transverse momentum of jet in supersonic crossflow, which is so-called counter-rotating vortices (CRVs) in the flat-plate injection. On account of the entrainment, the reflux in the cavity transports to the core of jet wakes, and then another pair of counter-rotating streamwise vortices is formed below with the effect of cavity. A pair of trailing CRVs is generated at the trailing edge of cavity, and the turbulent kinetic energy (TKE) here is obviously higher than that in other regions. To some extent, the cavity can enhance the mixing, but will not bring excess total pressure loss.

Trail resource impacts and an examination of alternative assessment techniques

USGS Publications Warehouse

Marion, J.L.; Leung, Y.-F.

2001-01-01

Trails are a primary recreation resource facility on which recreation activities are performed. They provide safe access to non-roaded areas, support recreational opportunities such as hiking, biking, and wildlife observation, and protect natural resources by concentrating visitor traffic on resistant treads. However, increasing recreational use, coupled with poorly designed and/or maintained trails, has led to a variety of resource impacts. Trail managers require objective information on trails and their conditions to monitor trends, direct trail maintenance efforts, and evaluate the need for visitor management and resource protection actions. This paper reviews trail impacts and different types of trail assessments, including inventory, maintenance, and condition assessment approaches. Two assessment methods, point sampling and problem assessment, are compared empirically from separate assessments of a 15-mile segment of the Appalachian Trail in Great Smoky Mountains National Park. Results indicate that point sampling and problem assessment methods yield distinctly different types of quantitative information. The point sampling method provides more accurate and precise measures of trail characteristics that are continuous or frequent (e.g., tread width or exposed soil). The problem assessment method is a preferred approach for monitoring trail characteristics that can be easily predefined or are infrequent (e.g., excessive width or secondary treads), particularly when information on the location of specific trail impact problems is needed. The advantages and limitations of these two assessment methods are examined in relation to various management and research information needs. The choice and utility of these assessment methods are also discussed.

Walking through time: heritage resources within the Appalachian Trail corridor

Treesearch

David M. Lacy; Karl Roenke

1998-01-01

Parts of the Appalachian Trail (and nearly half of Vermont's Long Trail) are located on New England National Forests, and managed in partnership with the Appalachian Trail Conference, Green Mountain Club, and other volunteers. Since the Trail corridor is a linear, if serpentine, sample of northern Appalachian highland environments it's not surprising that it...

Undercover EUV Solar Jets Observed by the Interface Region Imaging Spectrograph

NASA Astrophysics Data System (ADS)

Chen, N.-H.; Innes, D. E.

2016-12-01

It is well-known that extreme ultraviolet (EUV) emission emitted at the solar surface is absorbed by overlying cool plasma. Especially in active regions, dark lanes in EUV images suggest that much of the surface activity is obscured. Simultaneous observations from the Interface Region Imaging Spectrograph, consisting of UV spectra and slit-jaw images (SJI), give vital information with sub-arcsecond spatial resolution on the dynamics of jets not seen in EUV images. We studied a series of small jets from recently formed bipole pairs beside the trailing spot of active region 11991, which occurred on 2014 March 5 from 15:02:21 UT to 17:04:07 UT. Collimated outflows with bright roots were present in SJI 1400 Å (transition region) and 2796 Å (upper chromosphere) that were mostly not seen in Atmospheric Imaging Assembly (AIA) 304 Å (transition region) and AIA 171 Å (lower corona) images. The Si IV spectra show a strong blue wing enhancement, but no red wing, in the line profiles of the ejecta for all recurrent jets, indicating outward flows without twists. We see two types of Mg II line profiles produced by the jets spires: reversed and non-reversed. Mg II lines remain optically thick, but turn optically thin in the highly Doppler shifted wings. The energy flux contained in each recurrent jet is estimated using a velocity differential emission measure technique that measures the emitting power of the plasma as a function of the line-of-sight velocity. We found that all the recurrent jets release similar energy (108 erg cm-2 s-1) toward the corona and the downward component is less than 3%.

AGN jet-driven stochastic cold accretion in cluster cores

NASA Astrophysics Data System (ADS)

Prasad, Deovrat; Sharma, Prateek; Babul, Arif

2017-10-01

Several arguments suggest that stochastic condensation of cold gas and its accretion on to the central supermassive black hole (SMBH) is essential for active galactic nuclei (AGNs) feedback to work in the most massive galaxies that lie at the centres of galaxy clusters. Our 3-D hydrodynamic AGN jet-ICM (intracluster medium) simulations, looking at the detailed angular momentum distribution of cold gas and its time variability for the first time, show that the angular momentum of the cold gas crossing ≲1 kpc is essentially isotropic. With almost equal mass in clockwise and counterclockwise orientations, we expect a cancellation of the angular momentum on roughly the dynamical time. This means that a compact accretion flow with a short viscous time ought to form, through which enough accretion power can be channeled into jet mechanical energy sufficiently quickly to prevent a cooling flow. The inherent stochasticity, expected in feedback cycles driven by cold gas condensation, gives rise to a large variation in the cold gas mass at the centres of galaxy clusters, for similar cluster and SMBH masses, in agreement with the observations. Such correlations are expected to be much tighter for the smoother hot/Bondi accretion. The weak correlation between cavity power and Bondi power obtained from our simulations also matches observations.

A Tale of Two Trails: Exploring Different Paths to Success

PubMed Central

Walker, Jennifer G.; Evenson, Kelly R.; Davis, William J.; Bors, Philip; Rodríguez, Daniel A.

2016-01-01

Background This comparative case study investigates 2 successful community trail initiatives, using the Active Living By Design (ALBD) Community Action Model as an analytical framework. The model includes 5 strategies: preparation, promotion, programs, policy, and physical projects. Methods Key stakeholders at 2 sites participated in in-depth interviews (N = 14). Data were analyzed for content using Atlas Ti and grouped according to the 5 strategies. Results Preparation Securing trail resources was challenging, but shared responsibilities facilitated trail development. Promotions The initiatives demonstrated minimal physical activity encouragement strategies. Programs Community stakeholders did not coordinate programmatic opportunities for routine physical activity. Policy Trails’ inclusion in regional greenway master plans contributed to trail funding and development. Policies that were formally institutionalized and enforced led to more consistent trail construction and safer conditions for users. Physical Projects Consistent standards for way finding signage and design safety features enhanced trail usability and safety. Conclusions Communities with different levels of government support contributed unique lessons to inform best practices of trail initiatives. This study revealed a disparity between trail development and use-encouragement strategies, which may limit trails’ impact on physical activity. The ALBD Community Action Model provided a viable framework to structure cross-disciplinary community trail initiatives. PMID:21597125

The dusty silhouette jet HH 1019 in the Carina Nebula

NASA Astrophysics Data System (ADS)

Reiter, Megan; Kiminki, Megan M.; Smith, Nathan; Bally, John

2017-06-01

We report the discovery in Hubble Space Telescope (HST) images of the new Herbig-Haro jet, HH 1019, located near the Tr 14 cluster in the Carina Nebula. Like other HH jets in the region, this bipolar collimated flow emerges from the head of a dark dust pillar. However, HH 1019 is unique because - unlike all other HH jets known to date - it is identified by a linear chain of dark, dusty knots that are seen primarily in silhouette against the background screen of the H II region. Proper motions confirm that these dark condensations move along the jet axis at high speed. [S II] emission traces a highly collimated jet that is spatially coincident with these dust knots. The high extinction in the body of the jet suggests that this outflow has lifted a large amount of dust directly from the disc, although it is possible that it has entrained dust from its surrounding protostellar envelope before exiting the dust pillar. If dust in HH 1019 originates from the circumstellar disc, this provides further evidence for a jet launched from a range of radii in the disc, including those outside the dust sublimation radius. HH 1019 may be the prototype for a new subclass of dusty HH objects seen primarily in extinction against the background screen of a bright H II region. Such jets may be common, but difficult to observe because they require the special condition of a very bright background in order to be seen in silhouette.

36 CFR 261.20 - Pacific Crest National Scenic Trail.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Trail. 261.20 Section 261.20 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE PROHIBITIONS General Prohibitions § 261.20 Pacific Crest National Scenic Trail. It is prohibited to use a motorized vehicle on the Pacific Crest National Scenic Trail without a special-use...

ERTS-1 views the Great Lakes

NASA Technical Reports Server (NTRS)

Lyons, W. A.; Pease, S. R.

1973-01-01

The meteorological content of ERTS images, particularly mesoscale effects of the Great Lakes and air pollution dispersion is summarized. Summertime lake breeze frontal clouds and various winter lake-effect convection patterns and snow squalls are revealed in great detail. A clear-cut spiral vortex over southern Lake Michigan is related to a record early snow storm in the Chicago area. Marked cloud changes induced by orographic and frictional effects on Lake Michigan's lee shore snow squalls are seen. The most important finding, however, is a clear-cut example of alterations in cumulus convection by anthropogenic condensation and/or ice nuclei from northern Indiana steel mills during a snow squall situation. Jet aircraft condensation trails are also found with surprising frequency.

Nature Trails for the Visually Impaired.

ERIC Educational Resources Information Center

Schwartz, Jonathan R.

Many interpretive nature trails have been established for the visually impaired in recent years. The objectives of the investigation were to (a) identify what has been done in the past in the way of nature trail design for the visually impaired, (b) compare this with what professional workers for the visually impaired consider important in the…

Triptolide Enhances the Tumoricidal Activity of TRAIL Against Renal Cell Carcinoma

PubMed Central

James, Britnie R.; Murphy, Katherine A.; Schwertfeger, Kathryn L.; Sangwan, Veena; Banerjee, Sulagna; Saluja, Ashok K.; Griffith, Thomas S.

2015-01-01

Renal cell carcinoma (RCC) is resistant to traditional cancer therapies, and metastatic RCC (mRCC) is incurable. The shortcomings in current therapeutic options for patients with mRCC provide the rationale for the development of novel treatment protocols. TNF-related apoptosis-inducing ligand (TRAIL) has proven to be a potent inducer of tumor cell death in vitro and in vivo, and a number of TRAIL death receptor agonists (recombinant TRAIL or TRAIL death receptor-specific mAb) has been developed and tested clinically. Unfortunately the clinical efficacy of TRAIL has been underwhelming and is likely due to a number of possible mechanisms that render tumors resistant to TRAIL, prompting the search for drugs that increase tumor cell susceptibility to TRAIL. The objective of this study was to determine the effectiveness of combining the diterpene triepoxide triptolide, or its water-soluble prodrug, Minnelide, with TRAIL receptor agonists against RCC in vitro or in vivo, respectively. TRAIL-induced apoptotic death of human RCC cells was increased in the presence of triptolide. The triptolide-induced sensitization was accompanied by increased TRAIL-R2 (DR5) and decreased HSP70 expression. In vivo treatment of mice bearing orthotopic RCC (Renca) tumors showed the combination of Minnelide and agonistic anti-DR5 mAb significantly decreased tumor burden and increased animal survival compared to either therapy alone. Our data suggest triptolide/Minnelide sensitizes RCC cells to TRAIL-induced apoptosis through altered TRAIL death receptor and heat shock protein expression. PMID:26426449

Electronic Escape Trails for Firefighters

NASA Technical Reports Server (NTRS)

Jorgensen, Charles; Schipper, John; Betts, Bradley

2008-01-01

A proposed wireless-communication and data-processing system would exploit recent advances in radio-frequency identification devices (RFIDs) and software to establish information lifelines between firefighters in a burning building and a fire chief at a control station near but outside the building. The system would enable identification of trails that firefighters and others could follow to escape from the building, including identification of new trails should previously established trails become blocked. The system would include a transceiver unit and a computer at the control station, portable transceiver units carried by the firefighters in the building, and RFID tags that the firefighters would place at multiple locations as they move into and through the building (see figure). Each RFID tag, having a size of the order of a few centimeters, would include at least standard RFID circuitry and possibly sensors for measuring such other relevant environmental parameters as temperature, levels of light and sound, concentration of oxygen, concentrations of hazardous chemicals in smoke, and/or levels of nuclear radiation. The RFID tags would be activated and interrogated by the firefighters and control-station transceivers. Preferably, RFID tags would be configured to communicate with each other and with the firefighters units and the control station in an ordered sequence, with built-in redundancy. In a typical scenario, as firefighters moved through a building, they would scatter many RFID tags into smoke-obscured areas by use of a compressed-air gun. Alternatively or in addition, they would mark escape trails by dropping RFID tags at such points of interest as mantraps, hot spots, and trail waypoints. The RFID tags could be of different types, operating at different frequencies to identify their functions, and possibly responding by emitting audible beeps when activated by signals transmitted by transceiver units carried by nearby firefighters.

30 CFR 57.12039 - Protection of surplus trailing cables.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Protection of surplus trailing cables. 57.12039 Section 57.12039 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Electricity Surface and Underground § 57.12039 Protection of surplus trailing cables. Surplus trailing cables...

30 CFR 75.833 - Handling high-voltage trailing cables.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Handling high-voltage trailing cables. 75.833... High-Voltage Longwalls § 75.833 Handling high-voltage trailing cables. (a) Cable handling. (1) Miners must not handle energized trailing cables unless they are wearing high-voltage insulating gloves, which...

Getting TRAIL back on track for cancer therapy

PubMed Central

Lemke, J; von Karstedt, S; Zinngrebe, J; Walczak, H

2014-01-01

Unlike other members of the TNF superfamily, the TNF-related apoptosis-inducing ligand (TRAIL, also known as Apo2L) possesses the unique capacity to induce apoptosis selectively in cancer cells in vitro and in vivo. This exciting discovery provided the basis for the development of TRAIL-receptor agonists (TRAs), which have demonstrated robust anticancer activity in a number of preclinical studies. Subsequently initiated clinical trials testing TRAs demonstrated, on the one hand, broad tolerability but revealed, on the other, that therapeutic benefit was rather limited. Several factors that are likely to account for TRAs' sobering clinical performance have since been identified. First, because of initial concerns over potential hepatotoxicity, TRAs with relatively weak agonistic activity were selected to enter clinical trials. Second, although TRAIL can induce apoptosis in several cancer cell lines, it has now emerged that many others, and importantly, most primary cancer cells are resistant to TRAIL monotherapy. Third, so far patients enrolled in TRA-employing clinical trials were not selected for likelihood of benefitting from a TRA-comprising therapy on the basis of a valid(ated) biomarker. This review summarizes and discusses the results achieved so far in TRA-employing clinical trials in the light of these three shortcomings. By integrating recent insight on apoptotic and non-apoptotic TRAIL signaling in cancer cells, we propose approaches to introduce novel, revised TRAIL-based therapeutic concepts into the cancer clinic. These include (i) the use of recently developed highly active TRAs, (ii) the addition of efficient, but cancer-cell-selective TRAIL-sensitizing agents to overcome TRAIL resistance and (iii) employing proteomic profiling to uncover resistance mechanisms. We envisage that this shall enable the design of effective TRA-comprising therapeutic concepts for individual cancer patients in the future. PMID:24948009

Photo-excitable hybrid nanocomposites for image-guided photo/TRAIL synergistic cancer therapy.

PubMed

Lin, Gan; Zhang, Yang; Zhu, Congqing; Chu, Chengchao; Shi, Yesi; Pang, Xin; Ren, En; Wu, Yayun; Mi, Peng; Xia, Haiping; Chen, Xiaoyuan; Liu, Gang

2018-05-22

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) can induce apoptosis in cancer cells without toxicity to normal cells. However, the efficiency is greatly limited by its short half-life and wild resistance in various cancer cells. In this study, we reported a micellar hybrid nanoparticle to carry TRAIL ligand (denoted as IPN@TRAIL) for a novel photo-excited TRAIL therapy. These IPN@TRAIL offered increased TRAIL stability, prolonged half-life and enhanced tumor accumulation, monitored by dual mode imaging. Furthermore, IPN@TRAIL nanocomposites enhanced wrapped TRAIL therapeutic efficiency greatly towards resistant cancer cells by TRAIL nanovectorization. More importantly, when upon external laser, these nanocomposites not only triggered tumor photothermal therapy (PTT), but also upregulated the expression of death receptors (DR4 and DR5), resulting in a greater apoptosis mediated by co-delivered TRAIL ligand. Such photo/TRAIL synergistic effect showed its great killing effects in a controllable manner on TRAIL-resistant A549 tumor model bearing mice. Finally, these nanocomposites exhibited rapid clearance without obvious systemic toxicity. All these features rendered our nanocomposites a promising theranostic platform in cancer therapy. Copyright © 2018 Elsevier Ltd. All rights reserved.

Glucose Deprivation Induces ATF4-Mediated Apoptosis through TRAIL Death Receptors

PubMed Central

Iurlaro, Raffaella; Püschel, Franziska; León-Annicchiarico, Clara Lucía; O'Connor, Hazel; Martin, Seamus J.; Palou-Gramón, Daniel; Lucendo, Estefanía

2017-01-01

ABSTRACT Metabolic stress occurs frequently in tumors and in normal tissues undergoing transient ischemia. Nutrient deprivation triggers, among many potential cell death-inducing pathways, an endoplasmic reticulum (ER) stress response with the induction of the integrated stress response transcription factor ATF4. However, how this results in cell death remains unknown. Here we show that glucose deprivation triggered ER stress and induced the unfolded protein response transcription factors ATF4 and CHOP. This was associated with the nontranscriptional accumulation of TRAIL receptor 1 (TRAIL-R1) (DR4) and with the ATF4-mediated, CHOP-independent induction of TRAIL-R2 (DR5), suggesting that cell death in this context may involve death receptor signaling. Consistent with this, the ablation of TRAIL-R1, TRAIL-R2, FADD, Bid, and caspase-8 attenuated cell death, although the downregulation of TRAIL did not, suggesting ligand-independent activation of TRAIL receptors. These data indicate that stress triggered by glucose deprivation promotes the ATF4-dependent upregulation of TRAIL-R2/DR5 and TRAIL receptor-mediated cell death. PMID:28242652

Rails-to-Trails: A Valuable Resource for Outdoor Educators.

ERIC Educational Resources Information Center

Fischer, Jim

1993-01-01

Describes the rails-to-trails movement, particularly in Ontario, where abandoned railways are converted to trails for hiking, skiing, cycling, and horseback riding. Proposes the often controversial rails-to-trails issue as a resource for discussion in outdoor leadership classes, focusing on rural and urban viewpoints. Also suggests using the…

30 CFR 75.810 - High-voltage trailing cables; splices.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false High-voltage trailing cables; splices. 75.810... § 75.810 High-voltage trailing cables; splices. [Statutory Provisions] In the case of high-voltage cables used as trailing cables, temporary splices shall not be used and all permanent splices shall be...

30 CFR 18.35 - Portable (trailing) cables and cords.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Portable (trailing) cables and cords. 18.35... and Design Requirements § 18.35 Portable (trailing) cables and cords. (a) Portable cables and cords... a portable (trailing) cable shall not exceed 500 feet. Where the method of mining requires the...

On the Trail of Drug-Defying Superbugs

MedlinePlus

... On the Trail of Drug-Defying Superbugs Inside Life Science View All Articles | Inside Life Science Home Page On the Trail of Drug-Defying ... Other Findings About Our Resident Microbes This Inside Life Science article also appears on LiveScience . Learn about related ...

Subsonic characteristics of a twin-jet swept-wing fighter model with maneuvering devices

NASA Technical Reports Server (NTRS)

Ray, E. J.; Hollingsworth, E. G.

1973-01-01

An investigation has been conducted at Mach numbers ranging from 0.06 to 0.94 to determine the effects of various combinations of leading-edge slat devices on the static aerodynamic characteristics of a twin-jet swept-wing fighter model. The study also included a determination of the effects of wing leading-edge droop, trailing-edge chord-extensions, wing fences, and wing-planform and camber modifications. The angle-of-attack range generally extended from about minus 2 deg to 24 deg and the sideslip angles ranged from about minus 6 deg to 13 deg.

Triptolide enhances the tumoricidal activity of TRAIL against renal cell carcinoma.

PubMed

Brincks, Erik L; Kucaba, Tamara A; James, Britnie R; Murphy, Katherine A; Schwertfeger, Kathryn L; Sangwan, Veena; Banerjee, Sulagna; Saluja, Ashok K; Griffith, Thomas S

2015-12-01

Renal cell carcinoma (RCC) is resistant to traditional cancer therapies, and metastatic RCC (mRCC) is incurable. The shortcomings in current therapeutic options for patients with mRCC provide the rationale for the development of novel treatment protocols. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has proven to be a potent inducer of tumor cell death in vitro and in vivo, and a number of TRAIL death receptor agonists (recombinant TRAIL or TRAIL death receptor-specific mAb) have been developed and tested clinically. Unfortunately the clinical efficacy of TRAIL has been underwhelming and is likely due to a number of possible mechanisms that render tumors resistant to TRAIL, prompting the search for drugs that increase tumor cell susceptibility to TRAIL. The objective of this study was to determine the effectiveness of combining the diterpene triepoxide triptolide, or its water-soluble prodrug, Minnelide, with TRAIL receptor agonists against RCC in vitro or in vivo, respectively. TRAIL-induced apoptotic death of human RCC cells was increased in the presence of triptolide. The triptolide-induced sensitization was accompanied by increased TRAIL-R2 (DR5) and decreased heat shock protein 70 expression. In vivo treatment of mice bearing orthotopic RCC (Renca) tumors showed the combination of Minnelide and agonistic anti-DR5 mAb significantly decreased tumor burden and increased animal survival compared to either therapy alone. Our data suggest triptolide/Minnelide sensitizes RCC cells to TRAIL-induced apoptosis through altered TRAIL death receptor and heat shock protein expression. © 2015 FEBS.

Trail Pheromone of the Argentine Ant, Linepithema humile (Mayr) (Hymenoptera: Formicidae)

PubMed Central

Choe, Dong-Hwan; Villafuerte, David B.; Tsutsui, Neil D.

2012-01-01

The Argentine ant (Linepithema humile) is recognized as one of the world's most damaging invasive species. One reason for the ecological dominance of introduced Argentine ant populations is their ability to dominate food and habitat resources through the rapid mobilization and recruitment of thousands of workers. More than 30 years ago, studies showed that (Z)-9-hexadecenal strongly attracted Argentine ant workers in a multi-choice olfactometer, suggesting that (Z)-9-hexadecenal might be the trail pheromone, or a component of a trail pheromone mixture. Since then, numerous studies have considered (Z)-9-hexadecenal as the key component of the Argentine ant trails. Here, we report the first chemical analyses of the trails laid by living Argentine ants and find that (Z)-9-hexadecenal is not present in a detectible quantity. Instead, two iridoids, dolichodial and iridomyrmecin, appear to be the primary chemical constituents of the trails. Laboratory choice tests confirmed that Argentine ants were attracted to artificial trails comprised of these two chemicals significantly more often than control trails. Although (Z)-9-hexadecenal was not detected in natural trails, supplementation of artificial dolichodial+iridomyrmecin trails with an extremely low concentraion of (Z)-9-hexadecenal did increase the efficacy of the trail-following behavior. In stark contrast with previous dogma, our study suggests that dolichodial and iridomyrmecin are major components of the Argentine ant trail pheromone. (Z)-9-hexadecenal may act in an additive manner with these iridoids, but it does not occur in detectable quantities in Argentine ant recruitment trails. PMID:23028739

Bortezomib sensitises TRAIL-resistant HPV-positive head and neck cancer cells to TRAIL through a caspase-dependent, E6-independent mechanism.

PubMed

Bullenkamp, J; Raulf, N; Ayaz, B; Walczak, H; Kulms, D; Odell, E; Thavaraj, S; Tavassoli, M

2014-10-23

Human papillomavirus (HPV) is causative for a new and increasing form of head and neck squamous cell carcinomas (HNSCCs). Although localised HPV-positive cancers have a favourable response to radio-chemotherapy (RT/CT), the impact of HPV in advanced or metastatic HNSCC remains to be defined and targeted therapeutics need to be tested for cancers resistant to RT/CT. To this end, we investigated the sensitivity of HPV-positive and -negative HNSCC cell lines to TRAIL (tumour necrosis factor-related apoptosis-inducing ligand), which induces tumour cell-specific apoptosis in various cancer types. A clear correlation was observed between HPV positivity and resistance to TRAIL compared with HPV-negative head and neck cancer cell lines. All TRAIL-resistant HPV-positive cell lines tested were sensitised to TRAIL-induced cell death by treatment with bortezomib, a clinically approved proteasome inhibitor. Bortezomib-mediated sensitisation to TRAIL was associated with enhanced activation of caspase-8, -9 and -3, elevated membrane expression levels of TRAIL-R2, cytochrome c release and G2/M arrest. Knockdown of caspase-8 significantly blocked cell death induced by the combination therapy, whereas the BH3-only protein Bid was not required for induction of apoptosis. XIAP depletion increased the sensitivity of both HPV-positive and -negative cells to TRAIL alone or in combination with bortezomib. In contrast, restoration of p53 following E6 knockdown in HPV-positive cells had no effect on their sensitivity to either single or combination therapy, suggesting a p53-independent pathway for the observed response. In summary, bortezomib-mediated proteasome inhibition sensitises previously resistant HPV-positive HNSCC cells to TRAIL-induced cell death through a mechanism involving both the extrinsic and intrinsic pathways of apoptosis. The cooperative effect of these two targeted anticancer agents therefore represents a promising treatment strategy for RT/CT-resistant HPV

In-Trail Procedure (ITP) Algorithm Design

NASA Technical Reports Server (NTRS)

Munoz, Cesar A.; Siminiceanu, Radu I.

2007-01-01

The primary objective of this document is to provide a detailed description of the In-Trail Procedure (ITP) algorithm, which is part of the Airborne Traffic Situational Awareness In-Trail Procedure (ATSA-ITP) application. To this end, the document presents a high level description of the ITP Algorithm and a prototype implementation of this algorithm in the programming language C.

30 CFR 77.600 - Trailing cables; short-circuit protection; disconnecting devices.

Code of Federal Regulations, 2014 CFR

2014-07-01

... capacity in each ungrounded conductor. Disconnecting devices used to disconnect power from trailing cables... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Trailing cables; short-circuit protection... AREAS OF UNDERGROUND COAL MINES Trailing Cables § 77.600 Trailing cables; short-circuit protection...

30 CFR 77.600 - Trailing cables; short-circuit protection; disconnecting devices.

Code of Federal Regulations, 2013 CFR

2013-07-01

... capacity in each ungrounded conductor. Disconnecting devices used to disconnect power from trailing cables... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Trailing cables; short-circuit protection... AREAS OF UNDERGROUND COAL MINES Trailing Cables § 77.600 Trailing cables; short-circuit protection...

30 CFR 77.600 - Trailing cables; short-circuit protection; disconnecting devices.

Code of Federal Regulations, 2012 CFR

2012-07-01

... capacity in each ungrounded conductor. Disconnecting devices used to disconnect power from trailing cables... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Trailing cables; short-circuit protection... AREAS OF UNDERGROUND COAL MINES Trailing Cables § 77.600 Trailing cables; short-circuit protection...

30 CFR 77.600 - Trailing cables; short-circuit protection; disconnecting devices.

Code of Federal Regulations, 2011 CFR

2011-07-01

... capacity in each ungrounded conductor. Disconnecting devices used to disconnect power from trailing cables... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Trailing cables; short-circuit protection... AREAS OF UNDERGROUND COAL MINES Trailing Cables § 77.600 Trailing cables; short-circuit protection...

Experimental evaluation of certification trails using abstract data type validation

NASA Technical Reports Server (NTRS)

Wilson, Dwight S.; Sullivan, Gregory F.; Masson, Gerald M.

1993-01-01

Certification trails are a recently introduced and promising approach to fault-detection and fault-tolerance. Recent experimental work reveals many cases in which a certification-trail approach allows for significantly faster program execution time than a basic time-redundancy approach. Algorithms for answer-validation of abstract data types allow a certification trail approach to be used for a wide variety of problems. An attempt to assess the performance of algorithms utilizing certification trails on abstract data types is reported. Specifically, this method was applied to the following problems: heapsort, Hullman tree, shortest path, and skyline. Previous results used certification trails specific to a particular problem and implementation. The approach allows certification trails to be localized to 'data structure modules,' making the use of this technique transparent to the user of such modules.

Pheromone trailing behavior of the brown tree snake, Boiga irregularis.

PubMed

Greene, M J; Stark, S L; Mason, R T

2001-11-01

The ability of snakes to follow pheromone trails has significant consequences for survival and reproduction. Of particular importance is the ability of snakes to locate conspecifics during the breeding season via the detection of pheromone trails. In this study, the ability of male brown tree snakes (Boiga irregularis), a tropical, rear-fanged colubrid, to follow pheromone trails produced by reproductively active conspecifics was tested in the laboratory by using a Y maze. Males displayed a trailing response to both female and male pheromone trails over blank controls. As males of this species display ritualized combat behavior, these responses likely represent both direct and indirect mechanisms, respectively, for the location of potential mates in the wild. Males did not, however, discriminate between male and female trails when given a choice on the Y maze.

Using certification trails to achieve software fault tolerance

NASA Technical Reports Server (NTRS)

Sullivan, Gregory F.; Masson, Gerald M.

1993-01-01

A conceptually novel and powerful technique to achieve fault tolerance in hardware and software systems is introduced. When used for software fault tolerance, this new technique uses time and software redundancy and can be outlined as follows. In the initial phase, a program is run to solve a problem and store the result. In addition, this program leaves behind a trail of data called a certification trail. In the second phase, another program is run which solves the original problem again. This program, however, has access to the certification trail left by the first program. Because of the availability of the certification trail, the second phase can be performed by a less complex program and can execute more quickly. In the final phase, the two results are accepted as correct; otherwise an error is indicated. An essential aspect of this approach is that the second program must always generate either an error indication or a correct output even when the certification trail it receives from the first program is incorrect. The certification trail approach to fault tolerance was formalized and it was illustrated by applying it to the fundamental problem of finding a minimum spanning tree. Cases in which the second phase can be run concorrectly with the first and act as a monitor are discussed. The certification trail approach was compared to other approaches to fault tolerance. Because of space limitations we have omitted examples of our technique applied to the Huffman tree, and convex hull problems. These can be found in the full version of this paper.

77 FR 25910 - National Trails System Act and Railroad Rights-of-Way

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-02

...] National Trails System Act and Railroad Rights-of-Way AGENCY: Surface Transportation Board, DOT. ACTION...) for rail banking and interim trail use under the National Trails System Act (Trails Act). New rules are adopted that require the parties jointly to notify the Board when an interim trail use/rail...

Aerodynamic Performance Predictions of Single and Twin Jet Afterbodies

NASA Technical Reports Server (NTRS)

Carlson, John R.; Pao, S. Paul; Abdol-Hamid, Khaled S.; Jones, William T.

1995-01-01

The multiblock three-dimensional Navier-Stokes method PAB3D was utilized by the Component Integration Branch (formerly Propulsion Aerodynamics Branch) at the NASA-Langley Research Center in an international study sponsored by AGARD Working Group #17 for the assessment of the state-of-the-art of propulsion-airframe integration testing techniques and CFD prediction technologies. Three test geometries from ONERA involving fundamental flow physics and four geometries from NASA-LaRC involving realistic flow interactions of wing, body, tail, and jet plumes were chosen by the Working Group. An overview of results on four (1 ONERA and 3 LaRC) of the seven test cases is presented. External static pressures, integrated pressure drag and total drag were calculated for the Langley test cases and jet plume velocity profiles and turbulent viscous stresses were calculated for the ONERA test case. Only selected data from these calculations are presented in this paper. The complete data sets calculated by the participants will be presented in an AGARD summary report. Predicted surface static pressures compared favorably with experimental data for the Langley geometries. Predicted afterbody drag compared well with experiment. Predicted nozzle drag was typically low due to over-compression of the flow near the trailing edge. Total drag was typically high. Predicted jet plume quantities on the ONERA case compared generally well with data.

Snail Trails

ERIC Educational Resources Information Center

Galus, Pamela

2002-01-01

The slime trails of snails lead the author's students to a better understanding of science as inquiry and the processes of science. During this five-day activity, students get up close and personal with one of her favorite creatures, the land snail. Students begin by observing the organism and recording their observations. After making initial…

49 CFR 236.823 - Switch, trailing point.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Switch, trailing point. 236.823 Section 236.823 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Switch, trailing point. A switch, the points of which face away from traffic approaching in the direction...

49 CFR 236.823 - Switch, trailing point.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 4 2011-10-01 2011-10-01 false Switch, trailing point. 236.823 Section 236.823 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Switch, trailing point. A switch, the points of which face away from traffic approaching in the direction...

49 CFR 236.823 - Switch, trailing point.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 4 2012-10-01 2012-10-01 false Switch, trailing point. 236.823 Section 236.823 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Switch, trailing point. A switch, the points of which face away from traffic approaching in the direction...

49 CFR 236.823 - Switch, trailing point.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 4 2013-10-01 2013-10-01 false Switch, trailing point. 236.823 Section 236.823 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Switch, trailing point. A switch, the points of which face away from traffic approaching in the direction...

49 CFR 236.823 - Switch, trailing point.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 4 2014-10-01 2014-10-01 false Switch, trailing point. 236.823 Section 236.823 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Switch, trailing point. A switch, the points of which face away from traffic approaching in the direction...

Fast and flexible: argentine ants recruit from nearby trails.

PubMed

Flanagan, Tatiana P; Pinter-Wollman, Noa M; Moses, Melanie E; Gordon, Deborah M

2013-01-01

Argentine ants (Linepithema humile) live in groups of nests connected by trails to each other and to stable food sources. In a field study, we investigated whether some ants recruit directly from established, persistent trails to food sources, thus accelerating food collection. Our results indicate that Argentine ants recruit nestmates to food directly from persistent trails, and that the exponential increase in the arrival rate of ants at baits is faster than would be possible if recruited ants traveled from distant nests. Once ants find a new food source, they walk back and forth between the bait and sometimes share food by trophallaxis with nestmates on the trail. Recruiting ants from nearby persistent trails creates a dynamic circuit, like those found in other distributed systems, which facilitates a quick response to changes in available resources.

76 FR 35468 - Star-Spangled Banner National Historic Trail Advisory Council

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-17

... DEPARTMENT OF THE INTERIOR National Park Service Star-Spangled Banner National Historic Trail... the Advisory Committee on the Star-Spangled Banner National Historic Trail will hold a meeting. Designated through an amendment to the National Trails System Act (16 U.S.C. 1241), the trail consists of...

36 CFR 212.56 - Identification of designated roads, trails, and areas.

Code of Federal Regulations, 2010 CFR

2010-07-01

... roads, trails, and areas. 212.56 Section 212.56 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE TRAVEL MANAGEMENT Designation of Roads, Trails, and Areas for Motor Vehicle Use § 212.56 Identification of designated roads, trails, and areas. Designated roads, trails, and areas...

30 CFR 75.607 - Breaking trailing cable and power cable connections.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Breaking trailing cable and power cable... LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Trailing Cables § 75.607 Breaking trailing cable and power cable connections. [Statutory Provisions] Trailing cable and...

30 CFR 77.600 - Trailing cables; short-circuit protection; disconnecting devices.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Trailing cables; short-circuit protection... AREAS OF UNDERGROUND COAL MINES Trailing Cables § 77.600 Trailing cables; short-circuit protection; disconnecting devices. Short-circuit protection for trailing cables shall be provided by an automatic circuit...

A spatial exploration of informal trail networks within Great Falls Park, VA

USGS Publications Warehouse

Wimpey, Jeremy; Marion, Jeffrey L.

2011-01-01

Informal (visitor-created) trails represent a threat to the natural resources of protected natural areas around the globe. These trails can remove vegetation, displace wildlife, alter hydrology, alter habitat, spread invasive species, and fragment landscapes. This study examines informal and formal trails within Great Falls Park, VA, a sub-unit of the George Washington Memorial Parkway, managed by the U.S. National Park Service. This study sought to answer three specific questions: 1) Are the physical characteristics and topographic alignments of informal trails significantly different from formal trails, 2) Can landscape fragmentation metrics be used to summarize the relative impacts of formal and informal trail networks on a protected natural area? and 3) What can we learn from examining the spatial distribution of the informal trails within protected natural areas? Statistical comparisons between formal and informal trails in this park indicate that informal trails have less sustainable topographic alignments than their formal counterparts. Spatial summaries of the lineal and areal extent and fragmentation associated with the trail networks by park management zones compare park management goals to the assessed attributes. Hot spot analyses highlight areas of high trail density within the park and findings provide insights regarding potential causes for development of dense informal trail networks.

Alternative skid trail retirement options for steep terrain logging

Treesearch

Mathew F. Smidt; Randall K. Kolka

2001-01-01

In winter 1999-2000 trials of deep tillage and recontouring of skid trails were implemented on three sites in northeastern Kentucky, USA to examine their potential as skid trail retirement options. While effective, current Best Management Practices (BMPs) for trail retirement do not address two potential benefits of retirement: recovery of normal hill slope hydrology...

Alternative skid trail retirement options for steep terrain logging

Treesearch

Mathew F. Smidt; Randall K. Kelka

2001-01-01

In winter 1999-2000 trials of deep tillage and recontouring of skid trails were implemented on three sites in northeastern Kentucky, USA to examine their potential as skid trail retirement options. While effective, current Best Management Practices (BMPs) for trail retirement do not address two potential benefits of retirement: recovery of normal hill slope\\r\\...

30 CFR 77.605 - Breaking trailing cable and power cable connections.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Breaking trailing cable and power cable... OF UNDERGROUND COAL MINES Trailing Cables § 77.605 Breaking trailing cable and power cable connections. Trailing cable and power cable connections between cables and to power sources shall not be made...

30 CFR 77.601 - Trailing cables or portable cables; temporary splices.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Trailing cables or portable cables; temporary... OF UNDERGROUND COAL MINES Trailing Cables § 77.601 Trailing cables or portable cables; temporary splices. Temporary splices in trailing cables or portable cables shall be made in a workmanlike manner and...

30 CFR 77.605 - Breaking trailing cable and power cable connections.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Breaking trailing cable and power cable... OF UNDERGROUND COAL MINES Trailing Cables § 77.605 Breaking trailing cable and power cable connections. Trailing cable and power cable connections between cables and to power sources shall not be made...

30 CFR 77.605 - Breaking trailing cable and power cable connections.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Breaking trailing cable and power cable... OF UNDERGROUND COAL MINES Trailing Cables § 77.605 Breaking trailing cable and power cable connections. Trailing cable and power cable connections between cables and to power sources shall not be made...

30 CFR 77.605 - Breaking trailing cable and power cable connections.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Breaking trailing cable and power cable... OF UNDERGROUND COAL MINES Trailing Cables § 77.605 Breaking trailing cable and power cable connections. Trailing cable and power cable connections between cables and to power sources shall not be made...

30 CFR 77.605 - Breaking trailing cable and power cable connections.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Breaking trailing cable and power cable... OF UNDERGROUND COAL MINES Trailing Cables § 77.605 Breaking trailing cable and power cable connections. Trailing cable and power cable connections between cables and to power sources shall not be made...

Population dynamics of American dog ticks (Acari: Ixodidae) along park trails

USGS Publications Warehouse

Carroll, J.F.; Russek-Cohen, E.; Nichols, J.D.; Hines, J.E.

1991-01-01

We conclude a mark-recapture study in which drag-collected ticks were removed from some park trails weekly from April to July. Weekly survival rates (probability of surviving and remaining on the trails) were significantly lower on trials used heavily by hikers, horses, and pets than on trails used less frequently. Although usage was the only obvious difference among these trails, differences in weekly survival rate estimates may be attributable to differential success in acquiring hosts. The estimated probability of capturing a host-seeking tick located along a trail on a single drag was 0.20 on the drag alone, and 0.25 including the person dragging. When routes parallel to the trails and of equal lengths were dragged immediately after sampling the trails, only .apprxeq. 5% as many ticks (including ticks on the person dragging) were found off the trails as on them. We found no evidence of reduced tick numbers on removal trails, but this result should be considered inconclusive because the power of the discerning test was low. However, the data reported here provide insights into turnover rates of the adult Dermacentor variabilis population and effectiveness of the drag as a sampling device.

Certification trails and software design for testability

NASA Technical Reports Server (NTRS)

Sullivan, Gregory F.; Wilson, Dwight S.; Masson, Gerald M.

1993-01-01

Design techniques which may be applied to make program testing easier were investigated. Methods for modifying a program to generate additional data which we refer to as a certification trail are presented. This additional data is designed to allow the program output to be checked more quickly and effectively. Certification trails were described primarily from a theoretical perspective. A comprehensive attempt to assess experimentally the performance and overall value of the certification trail method is reported. The method was applied to nine fundamental, well-known algorithms for the following problems: convex hull, sorting, huffman tree, shortest path, closest pair, line segment intersection, longest increasing subsequence, skyline, and voronoi diagram. Run-time performance data for each of these problems is given, and selected problems are described in more detail. Our results indicate that there are many cases in which certification trails allow for significantly faster overall program execution time than a 2-version programming approach, and also give further evidence of the breadth of applicability of this method.

Miniature Trailing Edge Effector for Aerodynamic Control

NASA Technical Reports Server (NTRS)

Lee, Hak-Tae (Inventor); Bieniawski, Stefan R. (Inventor); Kroo, Ilan M. (Inventor)

2008-01-01

Improved miniature trailing edge effectors for aerodynamic control are provided. Three types of devices having aerodynamic housings integrated to the trailing edge of an aerodynamic shape are presented, which vary in details of how the control surface can move. A bucket type device has a control surface which is the back part of a C-shaped member having two arms connected by the back section. The C-shaped section is attached to a housing at the ends of the arms, and is rotatable about an axis parallel to the wing trailing edge to provide up, down and neutral states. A flip-up type device has a control surface which rotates about an axis parallel to the wing trailing edge to provide up, down, neutral and brake states. A rotating type device has a control surface which rotates about an axis parallel to the chord line to provide up, down and neutral states.

Mixing-induced fluid destratification and ullage condensation

NASA Technical Reports Server (NTRS)

Meserole, Jere S.; Jones, Ogden S.; Fortini, Anthony F.

1987-01-01

In many applications, on-orbit storage and transfer of cryogens will require forced mixing to control tank pressure without direct venting to space. During a no-vent transfer or during operation of a thermodynamic vent system in a cryogen storage tank, pressure control is achieved by circulating cool liquid to the liquid-vapor interface to condense some of the ullage vapor. To measure the pressure and temperature response rates in mixing-induced condensation, an experiment has been developed using Freon 11 to simulate the two-phase behavior of a cryogen. A thin layer at the liquid surface is heated to raise the tank pressure, and then a jet mixer is turned on to circulate the liquid, cool the surface, and reduce the pressure. Many nozzle configurations and flow rates are used. Tank pressure and the temperature profiles in the ullage and the liquid are measured. Initial data from this ground test are shown correlated with normal-gravity and drop-tower dye-mixing data. Pressure collapse times are comparable to the dye-mixing times, whereas the times needed for complete thermal mixing are much longer than the dye-mixing times.

Dichotomy of Solar Coronal Jets: Standard Jets and Blowout Jets

NASA Technical Reports Server (NTRS)

Moore, R. L.; Cirtain, J. W.; Sterling, A. C.; Falconer, D. A.

2010-01-01

By examining many X-ray jets in Hinode/XRT coronal X-ray movies of the polar coronal holes, we found that there is a dichotomy of polar X-ray jets. About two thirds fit the standard reconnection picture for coronal jets, and about one third are another type. We present observations indicating that the non-standard jets are counterparts of erupting-loop H alpha macrospicules, jets in which the jet-base magnetic arch undergoes a miniature version of the blowout eruptions that produce major CMEs. From the coronal X-ray movies we present in detail two typical standard X-ray jets and two typical blowout X-ray jets that were also caught in He II 304 Angstrom snapshots from STEREO/EUVI. The distinguishing features of blowout X-ray jets are (1) X-ray brightening inside the base arch in addition to the outside bright point that standard jets have, (2) blowout eruption of the base arch's core field, often carrying a filament of cool (T 10(exp 4) - 10(exp 5) K) plasma, and (3) an extra jet-spire strand rooted close to the bright point. We present cartoons showing how reconnection during blowout eruption of the base arch could produce the observed features of blowout X-ray jets. We infer that (1) the standard-jet/blowout-jet dichotomy of coronal jets results from the dichotomy of base arches that do not have and base arches that do have enough shear and twist to erupt open, and (2) there is a large class of spicules that are standard jets and a comparably large class of spicules that are blowout jets.

Fast and Flexible: Argentine Ants Recruit from Nearby Trails

PubMed Central

Flanagan, Tatiana P.; Pinter-Wollman, Noa M.; Moses, Melanie E.; Gordon, Deborah M.

2013-01-01

Argentine ants (Linepithema humile) live in groups of nests connected by trails to each other and to stable food sources. In a field study, we investigated whether some ants recruit directly from established, persistent trails to food sources, thus accelerating food collection. Our results indicate that Argentine ants recruit nestmates to food directly from persistent trails, and that the exponential increase in the arrival rate of ants at baits is faster than would be possible if recruited ants traveled from distant nests. Once ants find a new food source, they walk back and forth between the bait and sometimes share food by trophallaxis with nestmates on the trail. Recruiting ants from nearby persistent trails creates a dynamic circuit, like those found in other distributed systems, which facilitates a quick response to changes in available resources. PMID:23967129

Characteristics of a Direct Current-driven plasma jet operated in open air

NASA Astrophysics Data System (ADS)

Li, Xuechen; Di, Cong; Jia, Pengying; Bao, Wenting

2013-09-01

A DC-driven plasma jet has been developed to generate a diffuse plasma plume by blowing argon into the ambient air. The plasma plume, showing a cup shape with a diameter of several centimeters at a higher voltage, is a pulsed discharge despite a DC voltage is applied. The pulse frequency is investigated as a function of the voltage under different gap widths and gas flow rates. Results show that plasma bullets propagate from the hollow needle to the plate electrode by spatially resolved measurement. A supposition about non-electroneutral trail of the streamer is proposed to interpret these experimental phenomena.

UNDERCOVER EUV SOLAR JETS OBSERVED BY THE INTERFACE REGION IMAGING SPECTROGRAPH

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

Chen, N.-H.; Innes, D. E.

It is well-known that extreme ultraviolet (EUV) emission emitted at the solar surface is absorbed by overlying cool plasma. Especially in active regions, dark lanes in EUV images suggest that much of the surface activity is obscured. Simultaneous observations from the Interface Region Imaging Spectrograph, consisting of UV spectra and slit-jaw images (SJI), give vital information with sub-arcsecond spatial resolution on the dynamics of jets not seen in EUV images. We studied a series of small jets from recently formed bipole pairs beside the trailing spot of active region 11991, which occurred on 2014 March 5 from 15:02:21 UT tomore » 17:04:07 UT. Collimated outflows with bright roots were present in SJI 1400 Å (transition region) and 2796 Å (upper chromosphere) that were mostly not seen in Atmospheric Imaging Assembly (AIA) 304 Å (transition region) and AIA 171 Å (lower corona) images. The Si iv spectra show a strong blue wing enhancement, but no red wing, in the line profiles of the ejecta for all recurrent jets, indicating outward flows without twists. We see two types of Mg ii line profiles produced by the jets spires: reversed and non-reversed. Mg ii lines remain optically thick, but turn optically thin in the highly Doppler shifted wings. The energy flux contained in each recurrent jet is estimated using a velocity differential emission measure technique that measures the emitting power of the plasma as a function of the line-of-sight velocity. We found that all the recurrent jets release similar energy (10{sup 8} erg cm{sup −2} s{sup −1}) toward the corona and the downward component is less than 3%.« less

How Networks of Informal Trails Cause Landscape Level Damage to Vegetation.

PubMed

Barros, Agustina; Marina Pickering, Catherine

2017-07-01

When visitors are not constrained to remain on formal trails, informal trail networks can develop and damage plant communities in protected areas. These networks can form in areas with low growing vegetation, where formal trails are limited, where there is limited regulation and where vegetation is slow to recover once disturbed. To demonstrate the extent of impacts from unregulated recreational use, we assessed damage to alpine vegetation by hikers and pack animals in the highest protected area in the southern Hemisphere: Aconcagua Park, in the Andes. Within the 237 ha area surveyed in the Horcones Valley, over 19 km of trails were found, nearly all of which (94%) were informal. This network of trails resulted in the direct loss of 11.5 ha of vegetation and extensive fragmentation of alpine meadows (21 fragments) and steppe vegetation (68 fragments). When levels of disturbance off these trails were quantified using rapid visual assessments, 81% of 102 randomly located plots showed evidence of disturbance, with the severity of disturbance greatest close to trails. As a result, vegetation in 90% of the Valley has been damaged by visitor use, nearly all of it from unregulated use. These results highlight the extent to which informal trails and trampling off-trail can cause landscape damage to areas of high conservation value, and hence the importance of better regulation of visitor use. The methodology used for off-trail impact assessment can be easily applied or adapted for other popular protected areas where trampling off-trail is also an issue.

Airbag Trails-2

NASA Technical Reports Server (NTRS)

2004-01-01

This segment of the first color image from the panoramic camera on the Mars Exploration Rover Spirit shows the rover's airbag trails (upper left). These depressions in the soil were made when the airbags were deflated and retracted after landing.

Apigenin promotes TRAIL-mediated apoptosis regardless of ROS generation.

PubMed

Kang, Chang-Hee; Molagoda, Ilandarage Menu Neelaka; Choi, Yung Hyun; Park, Cheol; Moon, Dong-Oh; Kim, Gi-Young

2018-01-01

Apigenin is a bioactive flavone in several herbs including parsley, thyme, and peppermint. Apigenin possesses anti-cancer and anti-inflammatory properties; however, whether apigenin enhances TRAIL-mediated apoptosis in cancer cells is unknown. In the current study, we found that apigenin enhanced TRAIL-induced apoptosis by promoting caspase activation and death receptor 5 (DR5) expression and a chimeric antibody against DR5 completely blocked the apoptosis. Apigenin also upregulated reactive oxygen species (ROS) generation; however, intriguingly, ROS inhibitors, glutathione (GSH) or N-acetyl-l-cysteine (NAC), moderately increased apigenin/TRAIL-induced apoptosis. Additional results showed that an autophagy inducer, rapamycin, enhanced apigenin/TRAIL-mediated apoptosis by a slight increase of ROS generation. Accordingly, NAC and GSH rather decreased apigenin-induced autophagy formation, suggesting that apigenin-induced ROS generation increased autophagy formation. However, autophagy inhibitors, bafilomycin (BAF) and 3-methyladenine (3-MA), showed different result in apigenin/TRAIL-mediated apoptosis without ROS generation. 3-MA upregulated the apoptosis but remained ROS levels; however, no changes on apoptosis and ROS generation were observed by BAF treatment. Taken together, these findings reveal that apigenin enhances TRAIL-induced apoptosis by activating apoptotic caspases by upregulating DR5 expression regardless of ROS generation, which may be a promising strategy for an adjuvant of TRAIL. Copyright © 2017 Elsevier Ltd. All rights reserved.

Spanish jet: something more than gemstone with magical properties

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

Suarez-Ruiz, I.; Iglesias, M.J.

The first reference to the existence of jet in Spain dates back to the 7th century. Due to the magical powers attributed to this stone, it has always been considered a mysterious gem. Spanish jet is now a scarce natural resource. The article gives scientific explanation for the magical properties of Spanish jet. It is a humic coal, black in colour, bright, carves and polishes well and has a remarkably stability on exposure to the air, for centuries. Its composition is almost exclusively organic and FTIR analysis shows a high proportion of aliphatic over condensed aromatic structures. The conventional rankmore » parameters are not applicable as the results are contradictory. Carbon content and rank of organic matter suggest it is a high volatile bituminous coal, which agrees with the reflectance for phlobaphinite, the other maceral of the huminite/vitrinite group in this coal. These contradictory characteristics of Spanish jet are derived from an anomalous high enrichment of hydrogen. During coalification there is an increase in aromaticity which is responsible for the variation in coal rank parameters, carbon content and responsible for the variation in coal rank parameters, carbon content and vitrinite reflectance. The remarkable stability is attributed to the adsorbed hydrocarbons preventing easy access of oxygen. 2 figs.« less

The trail guide system as a backcountry management tool

Treesearch

Herbert E. Echelberger; Raymond E. Leonard; Marysewall Lindsey Hamblin

1978-01-01

A trail guide booklet containing a map, directional and distance data, and information about the natural and human history and management problems of a backcountry hiking trail was keyed to small, numbered, wooden markers along the trail. This system was evaluated on an 8-mile loop in the White Mountain National Forest in New Hampshire. The system may be useful for...

ONC201 Demonstrates Antitumor Effects in Both Triple-Negative and Non-Triple-Negative Breast Cancers through TRAIL-Dependent and TRAIL-Independent Mechanisms.

PubMed

Ralff, Marie D; Kline, Christina L B; Küçükkase, Ozan C; Wagner, Jessica; Lim, Bora; Dicker, David T; Prabhu, Varun V; Oster, Wolfgang; El-Deiry, Wafik S

2017-07-01

Breast cancer is a major cause of cancer-related death. TNF-related apoptosis-inducing ligand (TRAIL) has been of interest as a cancer therapeutic, but only a subset of triple-negative breast cancers (TNBC) is sensitive to TRAIL. The small-molecule ONC201 induces expression of TRAIL and its receptor DR5. ONC201 has entered clinical trials in advanced cancers. Here, we show that ONC201 is efficacious against both TNBC and non-TNBC cells ( n = 13). A subset of TNBC and non-TNBC cells succumbs to ONC201-induced cell death. In 2 of 8 TNBC cell lines, ONC201 treatment induces caspase-8 cleavage and cell death that is blocked by TRAIL-neutralizing antibody RIK2. The proapoptotic effect of ONC201 translates to in vivo efficacy in the MDA-MB-468 xenograft model. In most TNBC lines tested (6/8), ONC201 has an antiproliferative effect but does not induce apoptosis. ONC201 decreases cyclin D1 expression and causes an accumulation of cells in the G 1 phase of the cell cycle. pRb expression is associated with sensitivity to the antiproliferative effects of ONC201, and the compound synergizes with taxanes in less sensitive cells. All non-TNBC cells ( n = 5) are growth inhibited following ONC201 treatment, and unlike what has been observed with TRAIL, a subset ( n = 2) shows PARP cleavage. In these cells, cell death induced by ONC201 is TRAIL independent. Our data demonstrate that ONC201 has potent antiproliferative and proapoptotic effects in a broad range of breast cancer subtypes, through TRAIL-dependent and TRAIL-independent mechanisms. These findings develop a preclinical rationale for developing ONC201 as a single agent and/or in combination with approved therapies in breast cancer. Mol Cancer Ther; 16(7); 1290-8. ©2017 AACR . ©2017 American Association for Cancer Research.

Back in Time on a Mathematics Trail

ERIC Educational Resources Information Center

Moffett, Pamela

2010-01-01

The recently revised "Northern Ireland Primary Curriculum" recommends that teachers make use of the environment to extend children's understanding of mathematics. One approach to using the environment in mathematics is to take children on a mathematics trail. A mathematics trail uses the resources and features within the environment as a…

Filament Channel Formation, Eruption, and Jet Generation

NASA Astrophysics Data System (ADS)

DeVore, C. Richard; Antiochos, Spiro K.; Karpen, Judith T.

2017-08-01

The mechanism behind filament-channel formation is a longstanding mystery, while that underlying the initiation of coronal mass ejections and jets has been studied intensively but is not yet firmly established. In previous work, we and collaborators have investigated separately the consequences of magnetic-helicity condensation (Antiochos 2013) for forming filament channels (Zhao et al. 2015; Knizhnik et al. 2015, 2017a,b) and of the embedded-bipole model (Antiochos 1996) for generating reconnection-driven jets (Pariat et al. 2009, 2010, 2015, 2016; Wyper et al. 2016, 2017). Now we have taken a first step toward synthesizing these two lines of investigation. Our recent study (Karpen et al. 2017) of coronal-hole jets with gravity and wind employed an ad hoc, large-scale shear flow at the surface to introduce magnetic free energy and form the filament channel. In this effort, we replace the shear flow with an ensemble of local rotation cells, to emulate the Sun’s ever-changing granules and supergranules. As in our previous studies, we find that reconnection between twisted flux tubes within the closed-field region concentrates magnetic shear and free energy near the polarity inversion line, forming the filament channel. Onset of reconnection between this field and the external, unsheared, open field releases stored energy to drive the impulsive jet. We discuss the results of our new simulations with implications for understanding solar activity and space weather.

Gingerol sensitizes TRAIL-induced apoptotic cell death of glioblastoma cells

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

Lee, Dae-Hee, E-mail: leedneo@gmail.com; Kim, Dong-Wook; Jung, Chang-Hwa

Glioblastoma multiforme (GBM) is the most lethal and aggressive astrocytoma of primary brain tumors in adults. Although there are many clinical trials to induce the cell death of glioblastoma cells, most glioblastoma cells have been reported to be resistant to TRAIL-induced apoptosis. Here, we showed that gingerol as a major component of ginger can induce TRAIL-mediated apoptosis of glioblastoma. Gingerol increased death receptor (DR) 5 levels in a p53-dependent manner. Furthermore, gingerol decreased the expression level of anti-apoptotic proteins (survivin, c-FLIP, Bcl-2, and XIAP) and increased pro-apoptotic protein, Bax and truncate Bid, by generating reactive oxygen species (ROS). We alsomore » found that the sensitizing effects of gingerol in TRAIL-induced cell death were blocked by scavenging ROS or overexpressing anti-apoptotic protein (Bcl-2). Therefore, we showed the functions of gingerol as a sensitizing agent to induce cell death of TRAIL-resistant glioblastoma cells. This study gives rise to the possibility of applying gingerol as an anti-tumor agent that can be used for the purpose of combination treatment with TRAIL in TRAIL-resistant glioblastoma tumor therapy. - Highlights: • Most GBM cells have been reported to be resistant to TRAIL-induced apoptosis. • Gingerol enhances the expression level of anti-apoptotic proteins by ROS. • Gingerol enhances TRAIL-induced apoptosis through actions on the ROS–Bcl2 pathway.« less

Spectra of Full 3-D PIC Simulations of Finite Meteor Trails

NASA Astrophysics Data System (ADS)

Tarnecki, L. K.; Oppenheim, M. M.

2016-12-01

Radars detect plasma trails created by the billions of small meteors that impact the Earth's atmosphere daily, returning data used to infer characteristics of the meteoroid population and upper atmosphere. Researchers use models to investigate the dynamic evolution of the trails. Previously, all models assumed a trail of infinite length, due to the constraints of simulation techniques. We present the first simulations of 3D meteor trails of finite length. This change more accurately captures the physics of the trails. We characterize the turbulence that develops as the trail evolves and study the effects of varying the external electric field, altitude, and initial density. The simulations show that turbulence develops in all cases, and that trails travel with the neutral wind rather than electric field. Our results will allow us to draw more detailed and accurate information from non-specular radar observations of meteors.

Human Embryonic and Induced Pluripotent Stem Cells Express TRAIL Receptors and Can Be Sensitized to TRAIL-Induced Apoptosis

PubMed Central

Vinarsky, Vladimir; Krivanek, Jan; Rankel, Liina; Nahacka, Zuzana; Barta, Tomas; Jaros, Josef; Andera, Ladislav

2013-01-01

Death ligands and their tumor necrosis factor receptor (TNFR) family receptors are the best-characterized and most efficient inducers of apoptotic signaling in somatic cells. In this study, we analyzed whether these prototypic activators of apoptosis are also expressed and able to be activated in human pluripotent stem cells. We examined human embryonic stem cells (hESC) and human-induced pluripotent stem cells (hiPSC) and found that both cell types express primarily TNF-related apoptosis-inducing ligand (TRAIL) receptors and TNFR1, but very low levels of Fas/CD95. We also found that although hESC and hiPSC contain all the proteins required for efficient induction and progression of extrinsic apoptotic signaling, they are resistant to TRAIL-induced apoptosis. However, both hESC and hiPSC can be sensitized to TRAIL-induced apoptosis by co-treatment with protein synthesis inhibitors such as the anti-leukemia drug homoharringtonine (HHT). HHT treatment led to suppression of cellular FLICE inhibitory protein (cFLIP) and Mcl-1 expression and, in combination with TRAIL, enhanced processing of caspase-8 and full activation of caspase-3. cFLIP likely represents an important regulatory node, as its shRNA-mediated down-regulation significantly sensitized hESC to TRAIL-induced apoptosis. Thus, we provide the first evidence that, irrespective of their origin, human pluripotent stem cells express canonical components of the extrinsic apoptotic system and on stress can activate death receptor-mediated apoptosis. PMID:23806100

Promoting and developing a trail network across suburban, rural, and urban communities.

PubMed

Schasberger, Michele G; Hussa, Carol S; Polgar, Michael F; McMonagle, Julie A; Burke, Sharon J; Gegaris, Andrew J

2009-12-01

The Wyoming Valley Wellness Trails Partnership received an Active Living by Design grant late in 2003 for a project centered on a growing trail network linking urban, suburban, and rural communities in northeast Pennsylvania, a former coal region, in order to increase physical activity among residents. The partnership conducted research, collected information, created promotional documents, worked with partners on events and programs, and participated in trail planning. Local trail organizations continued planning and construction toward developing a trail network. Other partners spearheaded policy change in schools and worksites and worked toward downtown revitalization. The partnership assisted these efforts by providing a forum in which organizations could meet. The partnership became a central resource for information about local parks, trails, and outdoor recreational activities. The partnership increased awareness and use of recreational facilities. Trail partners constructed 22 miles of walking and biking trails. The partnership took advantage of an allied effort that created organizational capacity for wellness in schools and worksites. Messages promoting social and entertainment benefits of physical activity were more successful than those promoting health benefits. The existence of multiple small, independent trail organizations can help advance trail development through concurrent development efforts. Urban, suburban, and rural residents' conceptions of walkability may differ. Trails provide options for recreational and transportation-related physical activity across urban, suburban, and rural landscapes that are supported by all constituents. Trail builders can be strong allies in bringing active living to suburban and rural places.

Hiking trails and tourism impact assessment in protected area: Jiuzhaigou Biosphere Reserve, China.

PubMed

Li, Wenjun; Ge, Xiaodong; Liu, Chunyan

2005-09-01

More and more visitors are attracted to protected areas nowadays, which not only bring about economic increase but also seriously adverse impacts on the ecological environment. In protected areas, trails are linkage between visitors and natural ecosystem, so they concentrate most of the adverse impacts caused by visitors. The trampling problems on the trails have been received attentions in the tremendous researches. However, few of them have correlated the environmental impacts to trail spatial patterns. In this project, the trails were selected as assessment objective, the trampling problems trail widening, multiple trail, and root exposure were taken as assessment indicators to assess ecological impacts in the case study area Jiuzhaigou Biosphere Reserve, and two spatial index, connectivity and circularity, were taken to indicate the trail network spatial patterns. The research results showed that the appearing frequency of the trampling problems had inverse correlation with the circularity and connectivity of the trail network, while the problem extent had no correlation with the spatial pattern. Comparing with the pristine trails, the artificial maintenance for the trails such as wooden trails and flagstone trails could prohibit vegetation root from exposure effectively. The research finds will be useful for the future trail design and tourism management.

DICHOTOMY OF SOLAR CORONAL JETS: STANDARD JETS AND BLOWOUT JETS

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

Moore, Ronald L.; Cirtain, Jonathan W.; Sterling, Alphonse C.

2010-09-01

By examining many X-ray jets in Hinode/X-Ray Telescope coronal X-ray movies of the polar coronal holes, we found that there is a dichotomy of polar X-ray jets. About two thirds fit the standard reconnection picture for coronal jets, and about one third are another type. We present observations indicating that the non-standard jets are counterparts of erupting-loop H{alpha} macrospicules, jets in which the jet-base magnetic arch undergoes a miniature version of the blowout eruptions that produce major coronal mass ejections. From the coronal X-ray movies we present in detail two typical standard X-ray jets and two typical blowout X-ray jetsmore » that were also caught in He II 304 A snapshots from STEREO/EUVI. The distinguishing features of blowout X-ray jets are (1) X-ray brightening inside the base arch in addition to the outside bright point that standard jets have, (2) blowout eruption of the base arch's core field, often carrying a filament of cool (T {approx} 10{sup 4} - 10{sup 5} K) plasma, and (3) an extra jet-spire strand rooted close to the bright point. We present cartoons showing how reconnection during blowout eruption of the base arch could produce the observed features of blowout X-ray jets. We infer that (1) the standard-jet/blowout-jet dichotomy of coronal jets results from the dichotomy of base arches that do not have and base arches that do have enough shear and twist to erupt open, and (2) there is a large class of spicules that are standard jets and a comparably large class of spicules that are blowout jets.« less

30 CFR 57.12088 - Splicing trailing cables.

Code of Federal Regulations, 2014 CFR

2014-07-01

... cable reel or other power feed cable payout-retrieval system. However, a temporary splice may be made to... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Splicing trailing cables. 57.12088 Section 57... Underground Only § 57.12088 Splicing trailing cables. No splice, except a vulcanized splice or its equivalent...

30 CFR 57.12088 - Splicing trailing cables.

Code of Federal Regulations, 2011 CFR

2011-07-01

... cable reel or other power feed cable payout-retrieval system. However, a temporary splice may be made to... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Splicing trailing cables. 57.12088 Section 57... Underground Only § 57.12088 Splicing trailing cables. No splice, except a vulcanized splice or its equivalent...

30 CFR 57.12088 - Splicing trailing cables.

Code of Federal Regulations, 2013 CFR

2013-07-01

... cable reel or other power feed cable payout-retrieval system. However, a temporary splice may be made to... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Splicing trailing cables. 57.12088 Section 57... Underground Only § 57.12088 Splicing trailing cables. No splice, except a vulcanized splice or its equivalent...

30 CFR 57.12088 - Splicing trailing cables.

Code of Federal Regulations, 2012 CFR

2012-07-01

... cable reel or other power feed cable payout-retrieval system. However, a temporary splice may be made to... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Splicing trailing cables. 57.12088 Section 57... Underground Only § 57.12088 Splicing trailing cables. No splice, except a vulcanized splice or its equivalent...

77 FR 39733 - Proposed Information Collection; Comment Request: Appalachian Trail Management Partner Survey

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-05

... Collection; Comment Request: Appalachian Trail Management Partner Survey AGENCY: National Park Service (NPS... the Appalachian Trail Park Office (ATPO) to protect trail resources and provide for the public enjoyment and visitor experience of the Appalachian National Scenic Trail (Trail). To comply with the...

Mountain bike trail compaction relation to selected physical parameters

Treesearch

Jeff Hale; Rodney R. Zwick

2002-01-01

The purpose of this research is to explore the rates of compaction and their relation to trail contextual aspects of: soil type, slope and crown cover on a newly established mountain bike trail in the northern reach of Vermont. A random sample of 52 sites was selected for monitoring on the 1.09-mile trail. Three penetrometer readings were taken at each of the sample...

Recreational trails reduce the density of ground-dwelling birds in protected areas.

PubMed

Thompson, Bill

2015-05-01

Recreational disturbance associated with trails has been identified as one of the major factors causing a decline of native biodiversity within protected areas. However, despite the negative impacts that recreation can have on biodiversity, providing public access to nature is critical for the future of the conservation of biodiversity. As such, many protected area managers are looking for tools to help maintain a balance between public access and biodiversity conservation. The objectives of this study were to examine the impacts of recreational trails on forest-dwelling bird communities in eastern North America, identify functional guilds which are particularly sensitive to recreational trails, and derive guidelines for trail design to assist in managing the impacts of recreational trails on forest-dwelling birds. Trails within 24 publicly owned natural areas were mapped, and breeding bird communities were described with the use of point count surveys. The density of forest birds, particularly of those species which nest or forage on the ground, were significantly positively influenced by the amount of trail-free refuge habitat. Although management options to control trail use in non-staffed protected areas are limited, this study suggests that protected area managers could design and maintain a trail network that would minimize impacts on resident wildlife, while providing recreational opportunities for visitors, by designing their trail network to maximize the area of trail-free habitat.

Recreational Trails Reduce the Density of Ground-Dwelling Birds in Protected Areas

NASA Astrophysics Data System (ADS)

Thompson, Bill

2015-05-01

Recreational disturbance associated with trails has been identified as one of the major factors causing a decline of native biodiversity within protected areas. However, despite the negative impacts that recreation can have on biodiversity, providing public access to nature is critical for the future of the conservation of biodiversity. As such, many protected area managers are looking for tools to help maintain a balance between public access and biodiversity conservation. The objectives of this study were to examine the impacts of recreational trails on forest-dwelling bird communities in eastern North America, identify functional guilds which are particularly sensitive to recreational trails, and derive guidelines for trail design to assist in managing the impacts of recreational trails on forest-dwelling birds. Trails within 24 publicly owned natural areas were mapped, and breeding bird communities were described with the use of point count surveys. The density of forest birds, particularly of those species which nest or forage on the ground, were significantly positively influenced by the amount of trail-free refuge habitat. Although management options to control trail use in non-staffed protected areas are limited, this study suggests that protected area managers could design and maintain a trail network that would minimize impacts on resident wildlife, while providing recreational opportunities for visitors, by designing their trail network to maximize the area of trail-free habitat.

Assessing the influence of sustainable trail design and maintenance on soil loss.

PubMed

Marion, Jeffrey L; Wimpey, Jeremy

2017-03-15

Natural-surfaced trail systems are an important infrastructure component providing a means for accessing remote protected natural area destinations. The condition and usability of trails is a critical concern of land managers charged with providing recreational access while preserving natural conditions, and to visitors seeking high quality recreational opportunities and experiences. While an adequate number of trail management publications provide prescriptive guidance for designing, constructing, and maintaining natural-surfaced trails, surprisingly little research has been directed at providing a scientific basis for this guidance. Results from a review of the literature and three scientific studies are presented to model and clarify the influence of factors that substantially influence trail soil loss and that can be manipulated by trail professionals to sustain high traffic while minimizing soil loss over time. Key factors include trail grade, slope alignment angle, tread drainage features, and the amount of rock in tread substrates. A new Trail Sustainability Rating is developed and offered as a tool for evaluating or improving the sustainability of existing or new trails. Published by Elsevier Ltd.

Assessing the influence of sustainable trail design and maintenance on soil loss

USGS Publications Warehouse

Marion, Jeff; Wimpey, Jeremy

2017-01-01

Natural-surfaced trail systems are an important infrastructure component providing a means for accessing remote protected natural area destinations. The condition and usability of trails is a critical concern of land managers charged with providing recreational access while preserving natural conditions, and to visitors seeking high quality recreational opportunities and experiences. While an adequate number of trail management publications provide prescriptive guidance for designing, constructing, and maintaining natural-surfaced trails, surprisingly little research has been directed at providing a scientific basis for this guidance. Results from a review of the literature and three scientific studies are presented to model and clarify the influence of factors that substantially influence trail soil loss and that can be manipulated by trail professionals to sustain high traffic while minimizing soil loss over time. Key factors include trail grade, slope alignment angle, tread drainage features, and the amount of rock in tread substrates. A new Trail Sustainability Rating is developed and offered as a tool for evaluating or improving the sustainability of existing or new trails.

Jet in jet in M87

NASA Astrophysics Data System (ADS)

Sob'yanin, Denis Nikolaevich

2017-11-01

New high-resolution Very Long Baseline Interferometer observations of the prominent jet in the M87 radio galaxy show a persistent triple-ridge structure of the transverse 15-GHz profile with a previously unobserved ultra-narrow central ridge. This radio structure can reflect the intrinsic structure of the jet, so that the jet as a whole consists of two embedded coaxial jets. A relativistic magnetohydrodynamic model is considered in which an inner jet is placed inside a hollow outer jet and the electromagnetic fields, pressures and other physical quantities are found. The entire jet is connected to the central engine that plays the role of a unipolar inductor generating voltage between the jets and providing opposite electric currents, and the charge neutrality and current closure together with the electromagnetic fields between the jets can contribute to the jet stabilization. The constant voltage is responsible for the similar widening laws observed for the inner and outer jets. This jet-in-jet structure can indicate simultaneous operation of two different jet-launching mechanisms, one relating to the central supermassive black hole and the other to the surrounding accretion disc. An inferred magnetic field of 80 G at the base is sufficient to provide the observed jet luminosity.

30 CFR 75.601 - Short circuit protection of trailing cables.

Code of Federal Regulations, 2012 CFR

2012-07-01

... to disconnect power from trailing cables shall be plainly marked and identified and such devices... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Short circuit protection of trailing cables. 75... MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Trailing Cables § 75.601 Short...

30 CFR 75.601 - Short circuit protection of trailing cables.

Code of Federal Regulations, 2011 CFR

2011-07-01

... to disconnect power from trailing cables shall be plainly marked and identified and such devices... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Short circuit protection of trailing cables. 75... MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Trailing Cables § 75.601 Short...

30 CFR 75.601 - Short circuit protection of trailing cables.

Code of Federal Regulations, 2014 CFR

2014-07-01

... to disconnect power from trailing cables shall be plainly marked and identified and such devices... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Short circuit protection of trailing cables. 75... MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Trailing Cables § 75.601 Short...

30 CFR 75.601 - Short circuit protection of trailing cables.

Code of Federal Regulations, 2013 CFR

2013-07-01

... to disconnect power from trailing cables shall be plainly marked and identified and such devices... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Short circuit protection of trailing cables. 75... MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Trailing Cables § 75.601 Short...

Effective Dynamics of Microorganisms That Interact with Their Own Trail

NASA Astrophysics Data System (ADS)

Kranz, W. Till; Gelimson, Anatolij; Zhao, Kun; Wong, Gerard C. L.; Golestanian, Ramin

2016-07-01

Like ants, some microorganisms are known to leave trails on surfaces to communicate. We explore how trail-mediated self-interaction could affect the behavior of individual microorganisms when diffusive spreading of the trail is negligible on the time scale of the microorganism using a simple phenomenological model for an actively moving particle and a finite-width trail. The effective dynamics of each microorganism takes on the form of a stochastic integral equation with the trail interaction appearing in the form of short-term memory. For a moderate coupling strength below an emergent critical value, the dynamics exhibits effective diffusion in both orientation and position after a phase of superdiffusive reorientation. We report experimental verification of a seemingly counterintuitive perpendicular alignment mechanism that emerges from the model.

Helicopter rotor trailing edge noise. [noise prediction

NASA Technical Reports Server (NTRS)

Schlinker, R. H.; Amier, R. K.

1981-01-01

A two dimensional section of a helicopter main rotor blade was tested in an acoustic wind tunnel at close to full-scale Reynolds numbers to obtain boundary layer data and acoustic data for use in developing an acoustic scaling law and testing a first principles trailing edge noise theory. Results were extended to the rotating frame coordinate system to develop a helicopter rotor trailing edge noise prediction. Comparisons of the calculated noise levels with helicopter flyover spectra demonstrate that trailing edge noise contributes significantly to the total helicopter noise spectrum at high frequencies. This noise mechanism is expected to control the minimum rotor noise. In the case of noise radiation from a local blade segment, the acoustic directivity pattern is predicted by the first principles trailing edge noise theory. Acoustic spectra are predicted by a scaling law which includes Mach number, boundary layer thickness and observer position. Spectrum shape and sound pressure level are also predicted by the first principles theory but the analysis does not predict the Strouhal value identifying the spectrum peak.

49 CFR 230.98 - Driving, trailing, and engine truck axles.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Driving, trailing, and engine truck axles. 230.98... Locomotives and Tenders Running Gear § 230.98 Driving, trailing, and engine truck axles. (a) Condemning defects. Driving, trailing, and engine truck axles with any of the following defects shall be removed from...

36 CFR 212.51 - Designation of roads, trails, and areas.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Designation of roads, trails... AGRICULTURE TRAVEL MANAGEMENT Designation of Roads, Trails, and Areas for Motor Vehicle Use § 212.51 Designation of roads, trails, and areas. (a) General. Motor vehicle use on National Forest System roads, on...

49 CFR 230.98 - Driving, trailing, and engine truck axles.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Locomotives and Tenders Running Gear § 230.98 Driving, trailing, and engine truck axles. (a) Condemning defects. Driving, trailing, and engine truck axles with any of the following defects shall be removed from... 49 Transportation 4 2011-10-01 2011-10-01 false Driving, trailing, and engine truck axles. 230.98...

The association of trail use with weather-related factors on an urban greenway.

PubMed

Burchfield, Ryan A; Fitzhugh, Eugene C; Bassett, David R

2012-02-01

To study the association between weather-related measures and objectively measured trail use across 3 seasons. Weather has been reported as a barrier to outdoor physical activity (PA), but previous studies have explained only a small amount of the variance in PA using weather-related measures. The dependent variable of this study was trail use measured as mean hourly trail counts by an infrared trail counter located on a greenway. Each trail count represents 1 person breaking the infrared beam of the trail counter. Two sources of weather-related measures were obtained by a site-specific weather station and a public domain weather source. Temperature, relative humidity, and precipitation were significantly correlated with trail counts recorded during daylight hours. More precise hourly weather-related measures explained 42% of the variance in trail counts, regardless of the weather data source with temperature alone explaining 18% of the variance in trail counts. After controlling for all seasonal and weekly factors, every 1°F increase in temperature was associated with an increase of 1.1 trail counts/hr up to 76°F, at which point trail use began to slightly decrease. Weather-related factors have a moderate association with trail use along an urban greenway.

Recovery of condensate water quality in power generator's surface condenser

NASA Astrophysics Data System (ADS)

Kurniawan, Lilik Adib

2017-03-01

In PT Badak NGL Plant, steam turbines are used to drive major power generators, compressors, and pumps. Steam exiting the turbines is condensed in surface condensers to be returned to boilers. Therefore, surface condenser performance and quality of condensate water are very important. One of the recent problem was caused by the leak of a surface condenser of Steam Turbine Power Generator. Thesteam turbine was overhauled, leaving the surface condenser idle and exposed to air for more than 1.5 years. Sea water ingress due to tube leaks worsens the corrosionof the condenser shell. The combination of mineral scale and corrosion product resulting high conductivity condensate at outlet condenser when we restarted up, beyond the acceptable limit. After assessing several options, chemical cleaning was the best way to overcome the problem according to condenser configuration. An 8 hour circulation of 5%wt citric acid had succeed reducing water conductivity from 50 μmhos/cm to below 5 μmhos/cm. The condensate water, then meets the required quality, i.e. pH 8.3 - 9.0; conductivity ≤ 5 μmhos/cm, therefore the power generator can be operated normally without any concern until now.

ONC201 demonstrates anti-tumor effects in both triple negative and non-triple negative breast cancers through TRAIL-dependent and TRAIL-independent mechanisms

PubMed Central

Ralff, Marie D.; Kline, Christina L.B.; Küçükkase, Ozan C; Wagner, Jessica; Lim, Bora; Dicker, David T.; Prabhu, Varun V.; Oster, Wolfgang; El-Deiry, Wafik S.

2017-01-01

Breast cancer is a major cause of cancer-related death. TRAIL has been of interest as a cancer therapeutic, but only a subset of triple negative breast cancers (TNBC) is sensitive to TRAIL. The small molecule ONC201 induces expression of TRAIL and its receptor DR5. ONC201 has entered clinical trials in advanced cancers. Here we show that ONC201 is efficacious against both TNBC and non-TNBC cells (n=13). A subset of TNBC and non-TNBC cells succumb to ONC201-induced cell death. In 2/8 TNBC cell lines, ONC201 treatment induces caspase-8 cleavage and cell death that is blocked by TRAIL-neutralizing antibody RIK2. The pro-apoptotic effect of ONC201 translates to in vivo efficacy in the MDA-MB-468 xenograft model. In most TNBC lines tested (6/8) ONC201 has an anti-proliferative effect but does not induce apoptosis. ONC201 decreases cyclin D1 expression and causes an accumulation of cells in the G1 phase of the cell cycle. pRb expression is associated with sensitivity to the anti-proliferative effects of ONC201, and the compound synergizes with taxanes in less sensitive cells. All non-TNBC cells (n=5) are growth inhibited following ONC201 treatment, and unlike what has been observed with TRAIL, a subset (n=2) show PARP cleavage. In these cells, cell death induced by ONC201 is TRAIL-independent. Our data demonstrate that ONC201 has potent anti-proliferative and pro-apoptotic effects in a broad range of breast cancer subtypes, through TRAIL-dependent and TRAIL-independent mechanisms. These findings develop a pre-clinical rationale for developing ONC201 as a single agent and/or in combination with approved therapies in breast cancer. PMID:28424227

76 FR 26767 - Captain John Smith Chesapeake National Historic Trail Advisory Council

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-09

... Trail Advisory Council AGENCY: National Park Service, Interior. ACTION: Notice of meeting. SUMMARY: As... that the Advisory Committee on the Captain John Smith Chesapeake National Historic Trail will hold a meeting. Designated through an amendment to the National Trails System Act (16 U.S.C. 1241), the trail...

76 FR 52691 - Captain John Smith Chesapeake National Historic Trail Advisory Council

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-23

... Trail Advisory Council AGENCY: National Park Service, Interior. ACTION: Notice of meeting. SUMMARY: As... that the Advisory Committee on the Captain John Smith Chesapeake National Historic Trail will hold a meeting. Designated through an amendment to the National Trails System Act (16 U.S.C. 1241), the trail...

Gigantic jets produced by an isolated tropical thunderstorm near Réunion Island

NASA Astrophysics Data System (ADS)

Soula, Serge; van der Velde, Oscar; Montanya, Joan; Huet, Patrice; Barthe, Christelle; Bór, József

2011-10-01

Five gigantic jets (GJs) have been recorded with video and photograph cameras on 7 March 2010 above an isolated tropical storm east of Réunion Island. Three of them were produced before the storm reached its coldest cloud top temperature (approximately -81°C), and two others occurred during the cloud extension. Thanks to the close distance of observation (˜50 km), the luminosity within the cloud was recorded, and the events are analyzed in unprecedented detail. The tops of the GJs are estimated between 80 and 90 km. All these GJs are accompanied by long, continuous cloud illumination, and they are preceded and followed by intermittent optical flashes from the cloud, most of time without any cloud-to-ground (CG) flash simultaneously detected, which suggests they originated mainly as intracloud discharges and without any charge transfer to Earth. The CG lightning activity is observed to cease a few tens of seconds before the jets. According to ELF data recorded at Nagycenk, Hungary, the five GJs serve to raise negative charge. Their duration ranges from 333 to 850 ms. The leading jet has the most variable duration (33-167 ms) and propagates faster at higher altitudes. The trailing jet exhibits a continuous decrease of luminosity in different parts of the jet (lower channel, transition zone and, for most events, carrot sprite-like top) and in the cloud, with possible rebrightening. The lower channels (˜20-40 km altitude) produce blue luminosity which decreases with altitude and become more and more diffuse with time. The transition zone (around 40-65 km) consists of bright red, luminous beads slowly going up (˜104 m s-1), retracing the initial leading jet channels.

Partially turbulated trailing edge cooling passages for gas turbine nozzles

DOEpatents

Thatcher, Jonathan Carl; Burdgick, Steven Sebastian

2001-01-01

A plurality of passages are spaced one from the other along the length of a trailing edge of a nozzle vane in a gas turbine. The passages lie in communication with a cavity in the vane for flowing cooling air from the cavity through the passages through the tip of the trailing edge into the hot gas path. Each passage is partially turbulated and includes ribs in an aft portion thereof to provide enhanced cooling effects adjacent the tip of the trailing edge. The major portions of the passages are smooth bore. By this arrangement, reduced temperature gradients across the trailing edge metal are provided. Additionally, the inlets to each of the passages have a restriction whereby a reduced magnitude of compressor bleed discharge air is utilized for trailing edge cooling purposes.

Sesquiterpenes with TRAIL-resistance overcoming activity from Xanthium strumarium.

PubMed

Karmakar, Utpal K; Ishikawa, Naoki; Toume, Kazufumi; Arai, Midori A; Sadhu, Samir K; Ahmed, Firoj; Ishibashi, Masami

2015-08-01

The ability of TRAIL to selectively induce apoptosis in cancer cells while sparing normal cells makes it an attractive target for the development of new cancer therapy. In search of bioactive natural products for overcoming TRAIL-resistance from natural resources, we previously reported a number of active compounds. In our screening program on natural resources targeting overcoming TRAIL-resistance, activity-guided fractionations of the extract of Xanthium strumarium led to the isolation of five sesquiterpene compounds (1-5). 11α,13-dihydroxanthinin (2) and 11α,13-dihydroxanthuminol (3) were first isolated from natural resources and xanthinosin (1), desacetylxanthanol (4), and lasidiol p-methoxybenzoate (5) were known compounds. All compounds (1-5) showed potent TRAIL-resistance overcoming activity at 8, 20, 20, 16, and 16 μM, respectively, in TRAIL-resistant AGS cells. Compounds 1 and 5 enhanced the levels of apoptosis inducing proteins DR4, DR5, p53, CHOP, Bax, cleaved caspase-3, cleaved caspase-8, and cleaved caspase-9 and also decreased the levels of cell survival protein Bcl-2 in TRAIL-resistant AGS cells in a dose-dependent manner. Compound 1 also enhanced the levels of DR4 and DR5 proteins in a time-dependent manner. Thus, compounds 1 and 5 were found to induce both extrinsic and intrinsic apoptotic cell death. Compound 1 also exhibit TRAIL-resistance overcoming activity in DLD1, DU145, HeLa, and MCF7 cells but did not decrease viability in non-cancer HEK293 cells up to 8 μM. Copyright © 2015 Elsevier Ltd. All rights reserved.

30 CFR 75.830 - Splicing and repair of trailing cables.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Splicing and repair of trailing cables. 75.830... High-Voltage Longwalls § 75.830 Splicing and repair of trailing cables. (a) Splices and repairs. (1... and repairs to high-voltage trailing cables must be made: (i) Only by a qualified person trained in...

76 FR 8992 - National Trails System Act and Railroad Rights-of-Way

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-16

...] National Trails System Act and Railroad Rights-of-Way AGENCY: Surface Transportation Board, DOT. ACTION... procedures regarding the use of railroad rights-of-way for railbanking and interim trail use under the National Trails System Act (Trails Act). DATES: Comments are due by April 12, 2011; replies are due by May...

A cost-benefit analysis of physical activity using bike/pedestrian trails.

PubMed

Wang, Guijing; Macera, Caroline A; Scudder-Soucie, Barbara; Schmid, Tom; Pratt, Michael; Buchner, David

2005-04-01

From a public health perspective, a cost-benefit analysis of using bike/pedestrian trails in Lincoln, Nebraska, to reduce health care costs associated with inactivity was conducted. Data was obtained from the city's 1998 Recreational Trails Census Report and the literature. Per capita annual cost of using the trails was 209.28 U.S. dollars (59.28 U.S. dollars construction and maintenance, 150 U.S. dollars of equipment and travel). Per capita annual direct medical benefit of using the trails was 564.41 U.S. dollars. The cost-benefit ratio was 2.94, which means that every 1 U.S. dollar investment in trails for physical activity led to 2.94 U.S. dollars in direct medical benefit. The sensitivity analyses indicated the ratios ranged from 1.65 to 13.40. Therefore, building trails is cost beneficial from a public health perspective. The most sensitive parameter affecting the cost-benefit ratios were equipment and travel costs; however, even for the highest cost, every 1 U.S. dollar investment in trails resulted in a greater return in direct medical benefit.

Make a Nature Trail

ERIC Educational Resources Information Center

Johnson, Janice K.

1973-01-01

Discusses the planning, construction, use, and maintenance of a nature trail. Ideal for demonstrating interrelationships between plants and animals, conservation practices, wildlife management, plant succession, forestry, geologic features and other scientific phenomena. (JR)

Boeing's variable geometry chevron: morphing aerospace structures for jet noise reduction

NASA Astrophysics Data System (ADS)

Calkins, Frederick T.; Mabe, James H.; Butler, George W.

2006-03-01

Boeing is applying cutting edge smart material actuators to the next generation morphing technologies for aircraft. This effort has led to the Variable Geometry Chevrons (VGC), which utilize compact, light weight, and robust shape memory alloy (SMA) actuators. These actuators morph the shape of chevrons on the trailing edge of a jet engine in order to optimize acoustic and performance objectives at multiple flight conditions. We have demonstrated a technical readiness level of 7 by successfully flight testing the VGCs on a Boeing 777-300ER with GE-115B engines. In this paper we describe the VGC design, development and performance during flight test. Autonomous operation of the VGCs, which did not require a control system or aircraft power, was demonstrated. A parametric study was conducted showing the influence of VGC configurations on shockcell generated cabin noise reduction during cruise. The VGC system provided a robust test vehicle to explore chevron configurations for community and shockcell noise reduction. Most importantly, the VGC concept demonstrated an exciting capability to optimize jet nozzle performance at multiple flight conditions.

Best management practices for erosion control from bladed skid trails

Treesearch

Charles R. Wade; W. Michael Aust; M. Chad Bolding; William A. Lakel III

2012-01-01

Sediment from forest operations is primarily associated with roads and skid trails. We evaluated five skid trail closure treatments applied to bladed skid trails in the Virginia Piedmont. Closure treatments were Waterbars, Seed, Mulch, Pine slash, and Hardwood slash. Sediment traps were used to collect monthly sediment samples for one year. The Mulch, Pine slash, and...

The dynamics of foraging trails in the tropical arboreal ant Cephalotes goniodontus.

PubMed

Gordon, Deborah M

2012-01-01

The foraging behavior of the arboreal turtle ant, Cephalotes goniodontus, was studied in the tropical dry forest of western Mexico. The ants collected mostly plant-derived food, including nectar and fluids collected from the edges of wounds on leaves, as well as caterpillar frass and lichen. Foraging trails are on small pieces of ephemeral vegetation, and persist in exactly the same place for 4-8 days, indicating that food sources may be used until they are depleted. The species is polydomous, occupying many nests which are abandoned cavities or ends of broken branches in dead wood. Foraging trails extend from trees with nests to trees with food sources. Observations of marked individuals show that each trail is travelled by a distinct group of foragers. This makes the entire foraging circuit more resilient if a path becomes impassable, since foraging in one trail can continue while a different group of ants forms a new trail. The colony's trails move around the forest from month to month; from one year to the next, only one colony out of five was found in the same location. There is continual searching in the vicinity of trails: ants recruited to bait within 3 bifurcations of a main foraging trail within 4 hours. When bait was offered on one trail, to which ants recruited, foraging activity increased on a different trail, with no bait, connected to the same nest. This suggests that the allocation of foragers to different trails is regulated by interactions at the nest.

The Dynamics of Foraging Trails in the Tropical Arboreal Ant Cephalotes goniodontus

PubMed Central

Gordon, Deborah M.

2012-01-01

The foraging behavior of the arboreal turtle ant, Cephalotes goniodontus, was studied in the tropical dry forest of western Mexico. The ants collected mostly plant-derived food, including nectar and fluids collected from the edges of wounds on leaves, as well as caterpillar frass and lichen. Foraging trails are on small pieces of ephemeral vegetation, and persist in exactly the same place for 4–8 days, indicating that food sources may be used until they are depleted. The species is polydomous, occupying many nests which are abandoned cavities or ends of broken branches in dead wood. Foraging trails extend from trees with nests to trees with food sources. Observations of marked individuals show that each trail is travelled by a distinct group of foragers. This makes the entire foraging circuit more resilient if a path becomes impassable, since foraging in one trail can continue while a different group of ants forms a new trail. The colony’s trails move around the forest from month to month; from one year to the next, only one colony out of five was found in the same location. There is continual searching in the vicinity of trails: ants recruited to bait within 3 bifurcations of a main foraging trail within 4 hours. When bait was offered on one trail, to which ants recruited, foraging activity increased on a different trail, with no bait, connected to the same nest. This suggests that the allocation of foragers to different trails is regulated by interactions at the nest. PMID:23209749

Characteristics of physical activity levels among trail users in a U.S. national sample.

PubMed

Librett, John J; Yore, Michelle M; Schmid, Thomas L

2006-11-01

The Task Force on Community Preventive Services strongly recommends environmental interventions that include enhanced access to opportunities for physical activity, such as walking and cycling trails. Although accumulating evidence indicates that trails can be effective in increasing physical activity, little is known about trail users. Cross-sectional analysis of a national sample of 3717 adults from the HealthStyles and ConsumerStyles surveys using logistic regression to determine physical activity patterns and sociodemographic correlates related to trail use, and to identify support regarding trail development policies. Almost 13% (12.7%) of the sample reported using trails at least once a month and 24.3% at least once a week. People who reported using trails at least once a week were twice as likely than people who reported rarely or never using trails to meet physical activity recommendations (odds ratio=2.3, 95% confidence interval=1.9-2.8). Nearly half (43.6%) of the non-trail users supported expanded public spaces for people to exercise, and 36.4% of the non-trail users reported that they would be willing to pay more taxes to build more parks and trails in their community. Community trails facilitate physical activity, and almost half of frequent trail users report that access to trails and other green space is important in choosing a place to live. These results support the need for prospective research on whether newly built trails promote physical activity in previously inactive people.

TNF-related apoptosis-inducing ligand (TRAIL): A new path to anti-cancer therapies

PubMed Central

Holoch, Peter A.; Griffith, Thomas S.

2009-01-01

Since its discovery in 1995, tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), a member of the tumor necrosis factor super family, has been under intense focus because of its remarkable ability to induce apoptosis in malignant human cells while leaving normal cells unscathed. Consequently, activation of the apoptotic signaling pathway from the death-inducing TRAIL receptors provides an attractive, biologically-targeted approach to cancer therapy. A great deal of research has focused on deciphering the TRAIL receptor signaling cascade and intracellular regulation of this pathway, as many human tumor cells possess mechanisms of resistance to TRAIL-induced apoptosis. This review focuses on the currently state of knowledge regarding TRAIL signaling and resistance, the preclinical development of therapies targeted at TRAIL receptors and modulators of the pathway, and the results of clinical trials for cancer treatment that have emerged from this base of knowledge. TRAIL-based approaches to cancer therapy vary from systemic administration of recombinant, soluble TRAIL protein with or without the combination of traditional chemotherapy, radiation or novel anticancer agents to agonistic monoclonal antibodies directed against functional TRAIL receptors to TRAIL gene transfer therapy. A better understanding of TRAIL resistance mechanisms may allow for the development of more effective therapies that exploit this cell-mediated pathway to apoptosis. PMID:19836385

Roaring Fork Motor Nature Trail, Title Sheet Great Smoky ...

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

Roaring Fork Motor Nature Trail, Title Sheet - Great Smoky Mountains National Park Roads & Bridges, Roaring Fork Motor Nature Trail, Between Cherokee Orchard Road & U.S. Route 321, Gatlinburg, Sevier County, TN

Dyslipidemia and Diabetes Increase the OPG/TRAIL Ratio in the Cardiovascular System.

PubMed

Toffoli, Barbara; Fabris, Bruno; Bartelloni, Giacomo; Bossi, Fleur; Bernardi, Stella

2016-01-01

Background . Dyslipidemia and diabetes are two of the most well established risk factors for the development of cardiovascular disease (CVD). Both of them usually activate a complex range of pathogenic pathways leading to organ damage. Here we hypothesized that dyslipidemia and diabetes could affect osteoprotegerin (OPG) and TNF-related apoptosis-inducing ligand (TRAIL) expression in the vessels and the heart. Materials and Methods . Gene and protein expression of OPG, TRAIL, and OPG/TRAIL ratio were quantified in the aorta and the hearts of control mice, dyslipidemic mice, and diabetic mice. Results . Diabetes significantly increased OPG and the OPG/TRAIL ratio expression in the aorta, while dyslipidemia was the major determinant of the changes observed in the heart, where it significantly increased OPG and reduced TRAIL expression, thus increasing cardiac OPG/TRAIL ratio. Conclusions . This work shows that both dyslipidemia and diabetes affect OPG/TRAIL ratio in the cardiovascular system. This could contribute to the changes in circulating OPG/TRAIL which are observed in patients with diabetes and CVD. Most importantly, these changes could mediate/contribute to atherosclerosis development and cardiac remodeling.

Health Impact Assessment, Physical Activity and Federal Lands Trail Policy

PubMed Central

Davis, Sally M.; Cruz, Theresa H.; Kozoll, Richard L.

2016-01-01

Objectives The objectives of this paper are to describe the application of Health Impact Assessment (HIA) to inform trail decisions affecting a rural, under-resourced community and propose the routine integration of HIAs to enhance NEPA environmental assessments and environmental impact statements for trail decisions on federal lands. Methods Screening, scoping, assessment, recommendations, reporting, monitoring and evaluation are being used to examine the health impact of trail location and design. Results HIA recommendations are being integrated into the public lands National Environmental Protection Act process for planning access to a new segment of the Continental Divide National Scenic Trail. Potential users from a nearby rural New Mexico community and a region of almost one million may benefit from this HIA-informed planning. Conclusions HIA can be integrated into the policy and decision-making process for trails on public lands. PMID:27213163

Assessing children's cognitive flexibility with the Shape Trail Test.

PubMed

Chan, Amy Y C; Morgan, Sarah-Jane

2018-01-01

In this paper we report an initial validation of the Shape Trail Test-Child Version (STT-CV) with a non-clinical sample of children aged 6 to 9 years. The STT-CV has been developed as an age-appropriate and culturally fair direct downward extension of the Trail Making Test (TMT) for the assessment of cognitive flexibility. Children completed the STT-CV and four established measures of executive functions that assessed working memory, inhibitory control and task switching. Results showed the expected age-based differences in completion times for both parts of the STT-CV (Trail A and Trail B). Children's performance on the STT-CV correlated significantly with all four measures of executive functions. After controlling for the effects of chronological age, completion times for Trail B remained correlated with most other measures of executive functions. These findings provide emerging evidence for the utility of the STT-CV, and highlight the need for designing and using appropriate variants of the TMT in the behavioural assessment of cognitive flexibility in developmentally and culturally diverse populations.

1. Roaring Fork Motor Nature Trail, entrance sign. Great ...

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

1. Roaring Fork Motor Nature Trail, entrance sign. - Great Smoky Mountains National Park Roads & Bridges, Roaring Fork Motor Nature Trail, Between Cherokee Orchard Road & U.S. Route 321, Gatlinburg, Sevier County, TN

9. Roaring Fork Motor Nature Trail, Reagan House. Great ...

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

9. Roaring Fork Motor Nature Trail, Reagan House. - Great Smoky Mountains National Park Roads & Bridges, Roaring Fork Motor Nature Trail, Between Cherokee Orchard Road & U.S. Route 321, Gatlinburg, Sevier County, TN

Photoballistics of volcanic jet activity at Stromboli, Italy

NASA Technical Reports Server (NTRS)

Chouet, B.; Hamisevicz, N.; Mcgetchin, T. R.

1974-01-01

Two night eruptions of the volcano Stromboli were studied through 70-mm photography. Single-camera techniques were used. Particle sphericity, constant velocity in the frame, and radial symmetry were assumed. Properties of the particulate phase found through analysis include: particle size, velocity, total number of particles ejected, angular dispersion and distribution in the jet, time variation of particle size and apparent velocity distribution, averaged volume flux, and kinetic energy carried by the condensed phase. The frequency distributions of particle size and apparent velocities are found to be approximately log normal. The properties of the gas phase were inferred from the fact that it was the transporting medium for the condensed phase. Gas velocity and time variation, volume flux of gas, dynamic pressure, mass erupted, and density were estimated. A CO2-H2O mixture is possible for the observed eruptions. The flow was subsonic. Velocity variations may be explained by an organ pipe resonance. Particle collimation may be produced by a Magnus effect.

30 CFR 75.607 - Breaking trailing cable and power cable connections.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Breaking trailing cable and power cable....607 Breaking trailing cable and power cable connections. [Statutory Provisions] Trailing cable and power cable connections to junction boxes shall not be made or broken under load. ...

30 CFR 75.607 - Breaking trailing cable and power cable connections.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Breaking trailing cable and power cable....607 Breaking trailing cable and power cable connections. [Statutory Provisions] Trailing cable and power cable connections to junction boxes shall not be made or broken under load. ...

30 CFR 75.607 - Breaking trailing cable and power cable connections.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Breaking trailing cable and power cable....607 Breaking trailing cable and power cable connections. [Statutory Provisions] Trailing cable and power cable connections to junction boxes shall not be made or broken under load. ...

30 CFR 75.607 - Breaking trailing cable and power cable connections.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Breaking trailing cable and power cable....607 Breaking trailing cable and power cable connections. [Statutory Provisions] Trailing cable and power cable connections to junction boxes shall not be made or broken under load. ...

Adoptively transferred TRAIL+ T cells suppress GVHD and augment antitumor activity

PubMed Central

Ghosh, Arnab; Dogan, Yildirim; Moroz, Maxim; Holland, Amanda M.; Yim, Nury L.; Rao, Uttam K.; Young, Lauren F.; Tannenbaum, Daniel; Masih, Durva; Velardi, Enrico; Tsai, Jennifer J.; Jenq, Robert R.; Penack, Olaf; Hanash, Alan M.; Smith, Odette M.; Piersanti, Kelly; Lezcano, Cecilia; Murphy, George F.; Liu, Chen; Palomba, M. Lia; Sauer, Martin G.; Sadelain, Michel; Ponomarev, Vladimir; van den Brink, Marcel R.M.

2013-01-01

Current strategies to suppress graft-versus-host disease (GVHD) also compromise graft-versus-tumor (GVT) responses. Furthermore, most experimental strategies to separate GVHD and GVT responses merely spare GVT function without actually enhancing it. We have previously shown that endogenously expressed TNF-related apoptosis-inducing ligand (TRAIL) is required for optimal GVT activity against certain malignancies in recipients of allogeneic hematopoietic stem cell transplantation (allo-HSCT). In order to model a donor-derived cellular therapy, we genetically engineered T cells to overexpress TRAIL and adoptively transferred donor-type unsorted TRAIL+ T cells into mouse models of allo-HSCT. We found that murine TRAIL+ T cells induced apoptosis of alloreactive T cells, thereby reducing GVHD in a DR5-dependent manner. Furthermore, murine TRAIL+ T cells mediated enhanced in vitro and in vivo antilymphoma GVT response. Moreover, human TRAIL+ T cells mediated enhanced in vitro cytotoxicity against both human leukemia cell lines and against freshly isolated chronic lymphocytic leukemia (CLL) cells. Finally, as a model of off-the-shelf, donor-unrestricted antitumor cellular therapy, in vitro–generated TRAIL+ precursor T cells from third-party donors also mediated enhanced GVT response in the absence of GVHD. These data indicate that TRAIL-overexpressing donor T cells could potentially enhance the curative potential of allo-HSCT by increasing GVT response and suppressing GVHD. PMID:23676461

Contrail Formation in Aircraft Wakes Using Large-Eddy Simulations

NASA Technical Reports Server (NTRS)

Paoli, R.; Helie, J.; Poinsot, T. J.; Ghosal, S.

2002-01-01

In this work we analyze the issue of the formation of condensation trails ("contrails") in the near-field of an aircraft wake. The basic configuration consists in an exhaust engine jet interacting with a wing-tip training vortex. The procedure adopted relies on a mixed Eulerian/Lagrangian two-phase flow approach; a simple micro-physics model for ice growth has been used to couple ice and vapor phases. Large eddy simulations have carried out at a realistic flight Reynolds number to evaluate the effects of turbulent mixing and wake vortex dynamics on ice-growth characteristics and vapor thermodynamic properties.

8. Roaring Fork Motor Nature Trail, handbuilt rock pile. ...

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

8. Roaring Fork Motor Nature Trail, hand-built rock pile. - Great Smoky Mountains National Park Roads & Bridges, Roaring Fork Motor Nature Trail, Between Cherokee Orchard Road & U.S. Route 321, Gatlinburg, Sevier County, TN

Interferon-induced TRAIL-independent cell death in DNase II-/- embryos.

PubMed

Kitahara, Yusuke; Kawane, Kohki; Nagata, Shigekazu

2010-09-01

The chromosomal DNA of apoptotic cells and the nuclear DNA expelled from erythroid precursors is cleaved by DNase II in lysosomes after the cells or nuclei are engulfed by macrophages. DNase II(-/-) embryos suffer from lethal anemia due to IFN-beta produced in the macrophages carrying undigested DNA. Here, we show that Type I IFN induced a caspase-dependent cell death in human epithelial cells that were transformed to express a high level of IFN type I receptor. During this death process, a set of genes was strongly activated, one of which encoded TRAIL, a death ligand. A high level of TRAIL mRNA was also found in the fetal liver of the lethally anemic DNase II(-/-) embryos, and a lack of IFN type I receptor in the DNase II(-/-) IFN-IR(-/-) embryos blocked the expression of TRAIL mRNA. However, a null mutation in TRAIL did not rescue the lethal anemia of the DNase II(-/-) embryos, indicating that TRAIL is dispensable for inducing the apoptosis of erythroid cells in DNase II(-/-) embryos, and therefore, that there is a TRAIL-independent mechanism for the IFN-induced apoptosis.

Gingerol sensitizes TRAIL-induced apoptotic cell death of glioblastoma cells

PubMed Central

Lee, Dae-Hee; Kim, Dong-Wook; Jung, Chang-Hwa; Lee, Yong J.; Park, Daeho

2014-01-01

Glioblastoma multiforme (GBM) is the most lethal and aggressive astrocytoma of primary brain tumors in adults. Although there are many clinical trials to induce the cell death of glioblastoma cells, most glioblastoma cells have been reported to be resistant to TRAIL-induced apoptosis. Here, we showed that gingerol as a major component of ginger can induce TRAIL-mediated apoptosis of glioblastoma. Gingerol increased death receptor (DR) 5 levels in a p53-dependent manner. Furthermore, gingerol decreased the expression level of anti-apoptotic proteins (survivin, c-FLIP, Bcl-2, and XIAP) and increased pro-apoptotic protein, Bax and truncate Bid, by generating reactive oxygen species (ROS).We also found that the sensitizing effects of gingerol in TRAIL-induced cell death were blocked by scavenging ROS or overexpressing anti-apoptotic protein (Bcl-2). Therefore, we showed the functions of gingerol as a sensitizing agent to induce cell death of TRAIL-resistant glioblastoma cells. This study gives rise to the possibility of applying gingerol as an anti-tumor agent that can be used for the purpose of combination treatment with TRAIL in TRAIL-resistant glioblastoma tumor therapy. PMID:25034532

Survey of techniques for reduction of wind turbine blade trailing edge noise.

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

Barone, Matthew Franklin

2011-08-01

Aerodynamic noise from wind turbine rotors leads to constraints in both rotor design and turbine siting. The primary source of aerodynamic noise on wind turbine rotors is the interaction of turbulent boundary layers on the blades with the blade trailing edges. This report surveys concepts that have been proposed for trailing edge noise reduction, with emphasis on concepts that have been tested at either sub-scale or full-scale. These concepts include trailing edge serrations, low-noise airfoil designs, trailing edge brushes, and porous trailing edges. The demonstrated noise reductions of these concepts are cited, along with their impacts on aerodynamic performance. Anmore » assessment is made of future research opportunities in trailing edge noise reduction for wind turbine rotors.« less

Trailing edge flow conditions as a factor in airfoil design

NASA Technical Reports Server (NTRS)

Ormsbee, A. I.; Maughmer, M. D.

1984-01-01

Some new developments relevant to the design of single-element airfoils using potential flow methods are presented. In particular, the role played by the non-dimensional trailing edge velocity in design is considered and the relationship between the specified value and the resulting airfoil geometry is explored. In addition, the ramifications of the unbounded trailing edge pressure gradients generally present in the potential flow solution of the flow over an airfoil are examined, and the conditions necessary to obtain a class of airfoils having finite trailing edge pressure gradients developed. The incorporation of these conditions into the inverse method of Eppler is presented and the modified scheme employed to generate a number of airfoils for consideration. The detailed viscous analysis of airfoils having finite trailing edge pressure gradients demonstrates a reduction in the strong inviscid-viscid interactions generally present near the trailing edge of an airfoil.

30 CFR 77.804 - High-voltage trailing cables; minimum design requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false High-voltage trailing cables; minimum design... OF UNDERGROUND COAL MINES Surface High-Voltage Distribution § 77.804 High-voltage trailing cables; minimum design requirements. (a) High-voltage trailing cables used in resistance grounded systems shall be...

30 CFR 77.804 - High-voltage trailing cables; minimum design requirements.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false High-voltage trailing cables; minimum design... OF UNDERGROUND COAL MINES Surface High-Voltage Distribution § 77.804 High-voltage trailing cables; minimum design requirements. (a) High-voltage trailing cables used in resistance grounded systems shall be...

30 CFR 77.804 - High-voltage trailing cables; minimum design requirements.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false High-voltage trailing cables; minimum design... OF UNDERGROUND COAL MINES Surface High-Voltage Distribution § 77.804 High-voltage trailing cables; minimum design requirements. (a) High-voltage trailing cables used in resistance grounded systems shall be...

30 CFR 77.804 - High-voltage trailing cables; minimum design requirements.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false High-voltage trailing cables; minimum design... OF UNDERGROUND COAL MINES Surface High-Voltage Distribution § 77.804 High-voltage trailing cables; minimum design requirements. (a) High-voltage trailing cables used in resistance grounded systems shall be...

Effectiveness and costs of overland skid trail BMPs

Treesearch

Clay Sawyers; W. Michael Aust; M. Chad Bolding; William A. Lakel III

2012-01-01

Forestry Best Management Practices (BMPs) are designed to protect water quality; however, little data exists comparing the efficacy and costs of different BMP options for skid trail closure. Study objectives were to evaluate erosion control effectiveness and implementation costs of five overland skid trail closure techniques. Closure techniques were: waterbar only (...

Irigenin sensitizes TRAIL-induced apoptosis via enhancing pro-apoptotic molecules in gastric cancer cells.

PubMed

Xu, Ying; Gao, Cheng-Cheng; Pan, Zhen-Guo; Zhou, Chuan-Wen

2018-02-12

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) holds promising value for cancer therapy due to its capacity to induce apoptosis in cancer cells. Nevertheless, TRAIL therapy is greatly hampered by its resistance. Irigenin (Iri), isoflavonoids, can be isolated from the rhizome of Belamcanda chinensis, and has been shown anti-cancer properties. In this study, we explored if Iri could enhance TRAIL-regulated apoptosis in TRAIL resistant gastric cancer cells. Iri significantly potentiated TRAIL-triggered cytotoxicity. Iri alone and TRAIL alone showed no effective role in apoptosis induction, whereas combined treatment with Iri and TRAIL markedly induced apoptosis in cancer cells, as evidenced by the up-regulation of cleaved Caspase-8/-9/-3 and PARP. Additionally, the sensitization to TRAIL was along with the enhancement of pro-apoptotic proteins, including FAS-associated protein with death domain (FADD), death receptor 5 (DR5) and Bax. And suppressing FADD, DR5 and Bax by si RNA significantly reduced the apoptosis and enhanced the cell viability induced by the co-application of Iri and TRAIL. Moreover, the sensitization to TRAIL was accompanied by the decrease of Cellular-FLICE inhibitory protein (c-FLIP), Bcl-2 and Survivin. Additionally, Iri could sensitize TRAIL to produce reactive oxygen species (ROS). Pre-treatment of N-acetyl-cysteine (NAC), ROS scavenger, attenuated Iri plus TRAIL-induced apoptosis and improved cell viability. Finally, combination of Iri and TRAIL inhibited tumor growth in the xenograft model. Collectively, our present study gave new insights into the effects of Iri on potentiating TRAIL-sensitivity, and suggested that Iri could be a potential candidate for sensitizer of TRAIL-resistant cancer cell treatment. Copyright © 2018. Published by Elsevier Inc.

Dichotomous scoring of Trails B in patients referred for a dementia evaluation.

PubMed

Schmitt, Andrew L; Livingston, Ronald B; Smernoff, Eric N; Waits, Bethany L; Harris, James B; Davis, Kent M

2010-04-01

The Trail Making Test is a popular neuropsychological test and its interpretation has traditionally used time-based scores. This study examined an alternative approach to scoring that is simply based on the examinees' ability to complete the test. If an examinee is able to complete Trails B successfully, they are coded as "completers"; if not, they are coded as "noncompleters." To assess this approach to scoring Trails B, the performance of 97 diagnostically heterogeneous individuals referred for a dementia evaluation was examined. In this sample, 55 individuals successfully completed Trails B and 42 individuals were unable to complete it. Point-biserial correlations indicated a moderate-to-strong association (r(pb)=.73) between the Trails B completion variable and the Total Scale score of the Repeatable Battery for the Assessment of Neurological Status (RBANS), which was larger than the correlation between the Trails B time-based score and the RBANS Total Scale score (r(pb)=.60). As a screen for dementia status, Trails B completion showed a sensitivity of 69% and a specificity of 100% in this sample. These results suggest that dichotomous scoring of Trails B might provide a brief and clinically useful measure of dementia status.

Ambient air conditions and variation in urban trail use.

PubMed

Holmes, Ann M; Lindsey, Greg; Qiu, Chenchen

2009-11-01

This study examines the effect of air quality and administrative policies on use of urban trails in Indianapolis, IN. Attention is focused on two policy variables: (1) issuance of air pollution advisories and (2) the adoption of Daylight Savings Time. Results suggest that while trail use varies with air quality, current public advisories regarding air pollution may be of limited effectiveness in reducing trail users' exposures to hazardous pollutants. In contrast, the adoption of Daylight Savings Time was associated with a statistically significant increase in traffic levels.

Trail Marking by Caterpillars of the Silverspot Butterfly Dione Juno Huascuma

PubMed Central

Pescador-Rubio, Alfonso; Stanford-Camargo, Sergio G.; Páez-Gerardo, Luis E; Ramírez-Reyes, Alberto J.; Ibarra-Jiménez, René A.; Fitzgerald, Terrence D.

2011-01-01

A pheromone is implicated in the trail marking behavior of caterpillars of the nymphalid silverspot butterfly, Dione juno huascuma (Reakirt) (Lepidoptera: Heliconiinae) that feed gregariously on Passiflora (Malpighiales: Passifloraceae) vines in Mexico. Although they mark pathways leading from one feeding site to another with silk, this study shows that the silk was neither adequate nor necessary to elicit trail following behavior. Caterpillars marked trails with a long-lived pheromone that was deposited when they brushed the ventral surfaces of the tips of their abdomens along branch pathways. The caterpillars distinguished between pathways deposited by different numbers of siblings and between trails of different ages. Caterpillars also preferentially followed the trails of conspecifics over those of another nymphalid, Nymphalis antiopa L., the mourning cloak butterfly. PMID:21861659

SAHA-induced TRAIL-sensitisation of Multiple Myeloma cells is enhanced in 3D cell culture.

PubMed

Arhoma, A; Chantry, A D; Haywood-Small, S L; Cross, N A

2017-11-15

Multiple Myeloma (MM) is currently incurable despite many novel therapies. Tumour Necrosis Factor-Related Apoptosis-Inducing Ligand (TRAIL) is a potential anti-tumour agent although effects as a single agent are limited. In this study, we investigated whether the Histone Deacetylase (HDAC) inhibitor SAHA can enhance TRAIL-induced apoptosis and target TRAIL resistance in both suspension culture, and 3D cell culture as a model of disseminated MM lesions that form in bone. The effects of SAHA and/or TRAIL in 6 Multiple Myeloma cell lines were assessed in both suspension cultures and in an Alginate-based 3D cell culture model. The effect of SAHA and/or TRAIL was assessed on apoptosis by assessment of nuclear morphology using Hoechst 33342/Propidium Iodide staining. Viable cell number was assessed by CellTiter-Glo luminescence assay, Caspase-8 and -9 activities were measured by Caspase-Glo™ assay kit. TRAIL-resistant cells were generated by culture of RPMI 8226 and NCI-H929 by acute exposure to TRAIL followed by selection of TRAIL-resistant cells. TRAIL significantly induced apoptosis in a dose-dependent manner in OPM-2, RPMI 8226, NCI-H929, U266, JJN-3 MM cell lines and ADC-1 plasma cell leukaemia cells. SAHA amplified TRAIL responses in all lines except OPM-2, and enhanced TRAIL responses were both via Caspase-8 and -9. SAHA treatment induced growth inhibition that further increased in the combination treatment with TRAIL in MM cells. The co-treatment of TRAIL and SAHA reduced viable cell numbers all cell lines. TRAIL responses were further potentiated by SAHA in 3D cell culture in NCI-H929, RPMI 8226 and U266 at lower TRAIL + SAHA doses than in suspension culture. However TRAIL responses in cells that had been selected for TRAIL resistance were not further enhanced by SAHA treatment. SAHA is a potent sensitizer of TRAIL responses in both TRAIL sensitive and resistant cell lines, in both suspension and 3D culture, however SAHA did not sensitise TRAIL-sensitive cell

The jet-disk symbiosis without maximal jets: 1D hydrodynamical jets revisited

NASA Astrophysics Data System (ADS)

Crumley, Patrick; Ceccobello, Chiara; Connors, Riley M. T.; Cavecchi, Yuri

2017-05-01

In this work we discuss the recent criticism by Zdziarski (2016, A&A, 586, A18) of the maximal jet model derived in Falcke & Biermann (1995, A&A, 293, 665). We agree with Zdziarski that in general a jet's internal energy is not bounded by its rest-mass energy density. We describe the effects of the mistake on conclusions that have been made using the maximal jet model and show when a maximal jet is an appropriate assumption. The maximal jet model was used to derive a 1D hydrodynamical model of jets in agnjet, a model that does multiwavelength fitting of quiescent/hard state X-ray binaries and low-luminosity active galactic nuclei. We correct algebraic mistakes made in the derivation of the 1D Euler equation and relax the maximal jet assumption. We show that the corrections cause minor differences as long as the jet has a small opening angle and a small terminal Lorentz factor. We find that the major conclusion from the maximal jet model, the jet-disk symbiosis, can be generally applied to astrophysical jets. We also show that isothermal jets are required to match the flat radio spectra seen in low-luminosity X-ray binaries and active galactic nuclei, in agreement with other works.

30 CFR 75.827 - Guarding of trailing cables.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Guarding of trailing cables. 75.827 Section 75.827 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND...-Voltage Longwalls § 75.827 Guarding of trailing cables. (a) Guarding. (1) The high-voltage cable must be...

Indicators and protocols for monitoring impacts of formal and informal trails in protected areas

USGS Publications Warehouse

Marion, Jeffrey L.; Leung, Yu-Fai

2011-01-01

Trails are a common recreation infrastructure in protected areas and their conditions affect the quality of natural resources and visitor experiences. Various trail impact indicators and assessment protocols have been developed in support of monitoring programs, which are often used for management decision-making or as part of visitor capacity management frameworks. This paper reviews common indicators and assessment protocols for three types of trails, surfaced formal trails, unsurfaced formal trails, and informal (visitor-created) trails. Monitoring methods and selected data from three U.S. National Park Service units are presented to illustrate some common trail impact indicators and assessment options.

Ecological criteria, participant preferences and location models: A GIS approach toward ATV trail planning

Treesearch

Stephanie A. Snyder; Jay H. Whitmore; Ingrid E. Schneider; Dennis R. Becker

2008-01-01

This paper presents a geographic information system (GIS)-based method for recreational trail location for all-terrain vehicles (ATVs) which considers environmental factors, as well as rider preferences for trail attributes. The method utilizes the Least-Cost Path algorithm within a GIS framework to optimize trail location. The trail location algorithm considered trail...

Equivalence of the Color Trails Test and Trail Making Test in nonnative English-speakers.

PubMed

Dugbartey, A T; Townes, B D; Mahurin, R K

2000-07-01

The Color Trails Test (CTT) has been described as a culture-fair test of visual attention, graphomotor sequencing, and effortful executive processing abilities relative to the Trail Making Test (TMT). In this study, the equivalence of the TMT and the CTT among a group of 64 bilingual Turkish university students was examined. No difference in performance on the CTT-1 and TMT Part A was found, suggesting functionally equivalent performance across both tasks. In contrast, the statistically significant differences in performance on CTT-2 and TMT Part B, as well as the interference indices for both tests, were interpreted as providing evidence for task nonequivalence of the CTT-2 and TMT Part B. Results have implications for both psychometric test development and clinical cultural neuropsychology.

The interplay between scent trails and group-mass recruitment systems in ants.

PubMed

Planqué, Robert; van den Berg, Jan Bouwe; Franks, Nigel R

2013-10-01

Large ant colonies invariably use effective scent trails to guide copious ant numbers to food sources. The success of mass recruitment hinges on the involvement of many colony members to lay powerful trails. However, many ant colonies start off as single queens. How do these same colonies forage efficiently when small, thereby overcoming the hurdles to grow large? In this paper, we study the case of combined group and mass recruitment displayed by some ant species. Using mathematical models, we explore to what extent early group recruitment may aid deployment of scent trails, making such trails available at much smaller colony sizes. We show that a competition between group and mass recruitment may cause oscillatory behaviour mediated by scent trails. This results in a further reduction of colony size to establish trails successfully.

Visitor impacts on trails in the Sagarmatha (Mt. Everest) National Park, Nepal.

PubMed

Nepal, Sanjay K; Nepal, Stella Amor

2004-08-01

This study summarizes findings of a visitor impact study conducted in the Sagarmatha (Mt. Everest) National Park, Nepal. The effect of visitor use, and the influence of environmental characteristics on trail conditions are investigated. Seven trails divided into 208 trail segments, and with a total length of 90 kilometers were included in the assessment. A four-class rating system has been used for the assessment of trail conditions. Arc/Info and Arc/View geographic information system (GIS) are used to analyze spatial patterns of impacts. The study indicates a strong correlation between visitor use and trail degradation. However, locational and environmental factors are equally important variables. The study concludes that more systematic, and experimental studies are needed that can make a clear distinction between human-induced trail damage and the effects of natural factors.

Structural design of morphing trailing edge actuated by SMA

NASA Astrophysics Data System (ADS)

Wang, Qi; Xu, Zhiwei; Zhu, Qian

2013-09-01

In this paper, the morphing trailing edge is designed to achieve the up and down deflection under the aerodynamic load. After a detailed and accurate computational analysis to determine the SMA specifications and layout programs, a solid model is created in CATIA and the structures of the morphing wing trailing edge are produced by CNC machining. A set of DSP measurement and control system is designed to accomplish the controlling experiment of the morphing wing trailing edge. At last, via the force analysis, the trailing edge is fabricated with four sections of aluminum alloy, and the arrangement scheme of SMA wires is determined. Experiment of precise control integral has been performed to survey the control effect. The experiment consists of deflection angle tests of the third joint and the integral structure. Primarily, the ultimate deflection angle is tested in these two experiments. Therefore, the controlling experiment of different angles could be performed within this range. The results show that the deflection error is less than 4%and response time is less than 6.7 s, the precise controlling of the morphing trailing edge is preliminary realized.

Role of QCD monopoles in jet quenching

NASA Astrophysics Data System (ADS)

Ramamurti, Adith; Shuryak, Edward

2018-01-01

QCD monopoles are magnetically charged quasiparticles whose Bose-Einstein condensation (BEC) at T Tc is responsible for the unusual kinetic properties of quark-gluon plasma. In this paper, we study the contribution of the monopoles to jet quenching phenomenon, using the Baier-Dokshitzer-Mueller-Peigne-Schiff framework and hydrodynamic backgrounds. In the lowest order for cross sections, we calculate the nuclear modification factor, RAA, and azimuthal anisotropy, v2, of jets, as well as the dijet asymmetry, Aj, and compare those to the available data. We find relatively good agreement with experiment when using realistic hydrodynamic backgrounds. In addition, we find that event-by-event fluctuations are not necessary to reproduce RAA and v2 data, but play a role in Aj. Since the monopole-induced effects are maximal at T ≈Tc, we predict that their role should be significantly larger, relative to quarks and gluons, at lower RHIC energies.

Probing free jet expansions of supercritical fluids

NASA Astrophysics Data System (ADS)

Christen, W.; Rademann, K.

2009-10-01

Attempting to improve the comprehension of supersonic molecular beams at elevated pressures we present a comparative study of thermodynamic descriptions of the terminal flow velocity in free jet expansions. As model system we choose carbon dioxide due to its widespread utilization in supercritical fluid technology. Numerical results for the thermodynamic quantities are obtained using a high accuracy equation of state explicit in the Helmholtz free energy. The influence of pressure and temperature on the beam velocity is investigated for a broad range of stagnation conditions. A consistent physical picture is obtained for calculations employing the initial and final molar enthalpies, while enormous discrepancies are found for descriptions based on the molar isobaric heat capacity or the heat capacity ratio. The deviations are particularly pronounced at the gas-liquid phase transition and in the vicinity of the critical point and can be related to the diverse assumptions of ideal gas behavior. It is shown that computations using real fluid enthalpies permit to assess the fraction of condensation in supersonic jets.

Leading and Trailing Anvil Clouds of West African Squall Lines

NASA Technical Reports Server (NTRS)

Centrone, Jasmine; Houze, Robert A.

2011-01-01

The anvil clouds of tropical squall-line systems over West Africa have been examined using cloud radar data and divided into those that appear ahead of the leading convective line and those on the trailing side of the system. The leading anvils are generally higher in altitude than the trailing anvil, likely because the hydrometeors in the leading anvil are directly connected to the convective updraft, while the trailing anvil generally extends out of the lower-topped stratiform precipitation region. When the anvils are subdivided into thick, medium, and thin portions, the thick leading anvil is seen to have systematically higher reflectivity than the thick trailing anvil, suggesting that the leading anvil contains numerous larger ice particles owing to its direct connection to the convective region. As the leading anvil ages and thins, it retains its top. The leading anvil appears to add hydrometeors at the highest altitudes, while the trailing anvil is able to moisten a deep layer of the atmosphere.

Numerical Simulations of a Jet-Cloud Collision and Starburst: Application to Minkowski’s Object

NASA Astrophysics Data System (ADS)

Fragile, P. Chris; Anninos, Peter; Croft, Steve; Lacy, Mark; Witry, Jason W. L.

2017-12-01

We present results of three-dimensional, multi-physics simulations of an AGN jet colliding with an intergalactic cloud. The purpose of these simulations is to assess the degree of “positive feedback,” i.e., jet-induced star formation, that results. We have specifically tailored our simulation parameters to facilitate a comparison with recent observations of Minkowski’s Object (MO), a stellar nursery located at the termination point of a radio jet coming from galaxy NGC 541. As shown in our simulations, such a collision triggers shocks, which propagate around and through the cloud. These shocks condense the gas and under the right circumstances may trigger cooling instabilities, creating runaway increases in density, to the point that individual clumps can become Jeans unstable. Our simulations provide information about the expected star formation rate, total mass converted to H I, H2, and stars, and the relative velocity of the stars and gas. Our results confirm the possibility of jet-induced star formation, and agree well with the observations of MO.

Steam jet ejectors for the process industries. [Glossary included

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

Power, R.B.

1994-01-01

Steam jet ejectors were for many years the workhorse of the chemical process industries for producing vacuum. With increasing emphasis on stricter pollution control, their use was curtailed. There are still many applications, however, such as those with large capacity requirements, where ejectors are the only equipment that can produce sufficient vacuum. Chapter 1 is a short overview on how to use the text. Chapter 2 discusses what an ejector is and how it works. How ejector stages work is reviewed in Chapter 3. Engineering calculations for ejector stages is thoroughly discussed in Chapter 4. In Chapter 5, contact andmore » surface condensers are reviewed, and calculation procedures are presented. The various types of pressure control are discussed in Chapter 6. Chapter 7 is an excellent review of installation of ejector vacuum systems. The final chapter of Part 2 (Chapters 3--8) thoroughly covers all aspects of operation, testing, troubleshooting and maintenance. Part 3, consisting of two chapters, is devoted to specifying and purchasing steam jet ejectors. Part 4 on other ejector applications and upgrading ejector usage also consists of two chapters. Chapter 11 reviews steam-jet refrigeration, steam-jet and gas-jet compressors, liquid jet eductors, desuperheaters, special design situations, and designing one's own systems. Upgrading of existing ejector procedures and hardware is reviewed in Chapter 12. The 12 appendixes cover: physical properties of common fluids; handy vacuum engineering data and rules of thumb; SI unit conversions; sizing air and steam metering orifices for testing; drill sizes; ejector operating costs and design optimization; forms for ejector calculations, tests, and inspections; instructions for preparing ejector specifications; test kit contents list; ejector manufacturers and suppliers of referenced hardware and information; and failure modes and symptoms.« less

Microgravity Induction of TRAIL Expression in Preosteoclast Cells Enhances Osteoclast Differentiation

NASA Astrophysics Data System (ADS)

Sambandam, Yuvaraj; Baird, Kelsey L.; Stroebel, Maxwell; Kowal, Emily; Balasubramanian, Sundaravadivel; Reddy, Sakamuri V.

2016-05-01

Evidence indicates that astronauts experience significant bone loss in space. We previously showed that simulated microgravity (μXg) using the NASA developed rotary cell culture system (RCCS) enhanced bone resorbing osteoclast (OCL) differentiation. However, the mechanism by which μXg increases OCL formation is unclear. RANK/RANKL signaling pathway is critical for OCL differentiation. Tumor necrosis factor-related apoptosis inducing ligand (TRAIL) has been shown to increase osteoclastogenesis. We hypothesize that TRAIL may play an important role in μXg enhanced OCL differentiation. In this study, we identified by RT profiler PCR array screening that μXg induces high levels of TRAIL expression in murine preosteoclast cells in the absence of RANKL stimulation compared to ground based (Xg) cultures. We further identified that μXg elevated the adaptor protein TRAF-6 and fusion genes OC-STAMP and DC-STAMP expression in preosteoclast cells. Interestingly, neutralizing antibody against TRAIL significantly reduced μXg induced OCL formation. We further identified that over-expression of pTRAIL in RAW 264.7 cells enhanced OCL differentiation. These results indicate that TRAIL signaling plays an important role in the μXg increased OCL differentiation. Therefore, inhibition of TRAIL expression could be an effective countermeasure for μXg induced bone loss.

Home | Trails of Hope: Overland Diaries and Letters, 1846-1869 | Digital

Science.gov Websites

Letters, 1846-1869 Home Collections Overland Trails Home Search the Collection All Diaries Trail Maps Photographs & Illustrations Trail Guides Search Browse the Collection Search Browse Images and Text Browse Mormons--Religious Life Religious Life Women Browse Search Browse all Maps Interactive Maps These maps

Validation of Walking Trails for the Urban Training™ of Chronic Obstructive Pulmonary Disease Patients.

PubMed

Arbillaga-Etxarri, Ane; Torrent-Pallicer, Jaume; Gimeno-Santos, Elena; Barberan-Garcia, Anael; Delgado, Anna; Balcells, Eva; Rodríguez, Diego A; Vilaró, Jordi; Vall-Casas, Pere; Irurtia, Alfredo; Rodriguez-Roisin, Robert; Garcia-Aymerich, Judith

2016-01-01

Accessible interventions to train patients with chronic obstructive pulmonary disease (COPD) are needed. We designed urban trails of different intensities (low, moderate and high) in different types of public spaces (boulevard, beach and park). We aimed to validate the trails' design by assessing the physiological response to unsupervised walking trails of: (1) different intensities in COPD patients, and (2) same intensity from different public spaces in healthy adults. On different days and under standardized conditions, 10 COPD patients walked the three intensity trails designed in a boulevard space, and 10 healthy subjects walked the three intensity trails in three different spaces. We measured physiological response and energy expenditure using a gas analyzer. We compared outcomes across trails intensity and/or spaces using mixed-effects linear regression. In COPD patients, physiological response and energy expenditure increased significantly according to the trails intensity: mean (SD) peak V̇O2 15.9 (3.5), 17.4 (4.7), and 17.7 (4.4) mL/min/kg (p-trend = 0.02), and MET-min 60 (23), 64 (26), 72 (31) (p-trend<0.01) in low, moderate and high intensity trails, respectively. In healthy subjects there were no differences in physiological response to walking trails of the same intensity across different spaces. We validated the trails design for the training of COPD patients by showing that the physiological response to and energy expenditure on unsupervised walking these trails increased according to the predefined trails' intensity and did not change across trails of the same intensity in different public space. Walkable public spaces allow the design of trails that could be used for the training of COPD patients in the community.

Trails of Kilovolt Ions Created by Subsurface Channeling

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

Redinger, Alex; Standop, Sebastian; Michely, Thomas

2010-02-19

Using scanning tunneling microscopy, we observe the damage trails produced by keV noble-gas ions incident at glancing angles onto Pt(111). Surface vacancies and adatoms aligned along the ion trajectory constitute the ion trails. Atomistic simulations reveal that these straight trails are produced by nuclear (elastic) collisions with surface layer atoms during subsurface channeling of the projectiles. In a small energy window around 5 keV, Xe{sup +} ions create vacancy grooves that mark the ion trajectory with atomic precision. The asymmetry of the adatom production on the two sides of the projectile path is traced back to the asymmetry of themore » ion's subsurface channel.« less

Trail impacts in Sagarmatha (Mt. Everest) National Park, Nepal: a logistic regression analysis.

PubMed

Nepal, S K

2003-09-01

A trail study was conducted in the Sagarmatha (Mt. Everest) National Park, Nepal, during 1997-1998. Based on that study, this paper examines the spatial variability of trail conditions and analyzes factors that influence trail conditions. Logistic regression (multinomial logit model) is applied to examine the influence of use and environmental factors on trail conditions. The assessment of trail conditions is based on a four-class rating system: (class I, very little damaged; class II, moderately damaged, class III, heavily damaged; and class IV, severely damaged). Wald statistics and a model classification table have been used for data interpretation. Results indicate that altitude, trail gradient, hazard potential, and vegetation type are positively associated with trail condition. Trails are more degraded at higher altitude, on steep gradients, in areas with natural hazard potential, and within shrub/grassland zones. Strong correlations between high levels of trail degradation and higher frequencies of visitors and lodges were found. A detailed analysis of environmental and use factors could provide valuable information to park managers in their decisions about trail design, layout and maintenance, and efficient and effective visitor management strategies. Comparable studies on high alpine environments are needed to predict precisely the effects of topographic and climatic extremes. More refined approaches and experimental methods are necessary to control the effects of environmental factors.

25 CFR 247.20 - What are the road and trail prohibitions?

Code of Federal Regulations, 2010 CFR

2010-04-01

... 25 Indians 1 2010-04-01 2010-04-01 false What are the road and trail prohibitions? 247.20 Section... RIVER TREATY FISHING ACCESS SITES § 247.20 What are the road and trail prohibitions? (a) You cannot damage or leave in a damaged condition any road, trail, or segment thereof. (b) You cannot block...

Records of Backcountry Use Can Assist Trail Managers

Treesearch

H.J. Plumley; H.T. Peet; R.E. Leonard

1978-01-01

Records of recreational use of Eastern backcountry areas have not been systematically kept by many trail management groups in the past. Decisions on backcountry site designs and facilities should not be made without information on visitor use and behavior. An analysis of sample data from records of overnight shelter use on the Long Trail, Vermont, indicates how such...

A trail pheromone component of the ant Mayriella overbecki Viehmeyer (Formicidae: Myrmicinae)

NASA Astrophysics Data System (ADS)

Kohl, E.; Hölldobler, B.; Bestmann, H.-J.

The myrmicine ant Mayriella overbecki lays recruitment trails during foraging and nest emigrations. The trail pheromone originates from the poison gland. From ten identified components of the poison gland secretions only methyl 6-methylsalicylate 1 elicited trail following behavior.

CFD simulation of water vapour condensation in the presence of non-condensable gas in vertical cylindrical condensers.

PubMed

Li, Jun-De

2013-02-01

This paper presents the simulation of the condensation of water vapour in the presence of non-condensable gas using computational fluid dynamics (CFD) for turbulent flows in a vertical cylindrical condenser tube. The simulation accounts for the turbulent flow of the gas mixture, the condenser wall and the turbulent flow of the coolant in the annular channel with no assumptions of constant wall temperature or heat flux. The condensate film is assumed to occupy a negligible volume and its effect on the condensation of the water vapour has been taken into account by imposing a set of boundary conditions. A new strategy is used to overcome the limitation of the currently available commercial CFD package to solve the simultaneous simulation of flows involving multispecies and fluids of gas and liquid in separate channels. The results from the CFD simulations are compared with the experimental results from the literature for the condensation of water vapour with air as the non-condensable gas and for inlet mass fraction of the water vapour from 0.66 to 0.98. The CFD simulation results in general agree well with the directly measured quantities and it is found that the variation of heat flux in the condenser tube is more complex than a simple polynomial curve fit. The CFD results also show that, at least for flows involving high water vapour content, the axial velocity of the gas mixture at the interface between the gas mixture and the condensate film is in general not small and cannot be neglected.

CFD simulation of water vapour condensation in the presence of non-condensable gas in vertical cylindrical condensers

PubMed Central

Li, Jun-De

2013-01-01

This paper presents the simulation of the condensation of water vapour in the presence of non-condensable gas using computational fluid dynamics (CFD) for turbulent flows in a vertical cylindrical condenser tube. The simulation accounts for the turbulent flow of the gas mixture, the condenser wall and the turbulent flow of the coolant in the annular channel with no assumptions of constant wall temperature or heat flux. The condensate film is assumed to occupy a negligible volume and its effect on the condensation of the water vapour has been taken into account by imposing a set of boundary conditions. A new strategy is used to overcome the limitation of the currently available commercial CFD package to solve the simultaneous simulation of flows involving multispecies and fluids of gas and liquid in separate channels. The results from the CFD simulations are compared with the experimental results from the literature for the condensation of water vapour with air as the non-condensable gas and for inlet mass fraction of the water vapour from 0.66 to 0.98. The CFD simulation results in general agree well with the directly measured quantities and it is found that the variation of heat flux in the condenser tube is more complex than a simple polynomial curve fit. The CFD results also show that, at least for flows involving high water vapour content, the axial velocity of the gas mixture at the interface between the gas mixture and the condensate film is in general not small and cannot be neglected. PMID:24850953

Twin Jet

NASA Technical Reports Server (NTRS)

Henderson, Brenda; Bozak, Rick

2010-01-01

Many subsonic and supersonic vehicles in the current fleet have multiple engines mounted near one another. Some future vehicle concepts may use innovative propulsion systems such as distributed propulsion which will result in multiple jets mounted in close proximity. Engine configurations with multiple jets have the ability to exploit jet-by-jet shielding which may significantly reduce noise. Jet-by-jet shielding is the ability of one jet to shield noise that is emitted by another jet. The sensitivity of jet-by-jet shielding to jet spacing and simulated flight stream Mach number are not well understood. The current experiment investigates the impact of jet spacing, jet operating condition, and flight stream Mach number on the noise radiated from subsonic and supersonic twin jets.

The Influence of Snowmobile Trails on Coyote Movements during Winter in High-Elevation Landscapes

PubMed Central

Gese, Eric M.; Dowd, Jennifer L. B.; Aubry, Lise M.

2013-01-01

Competition between sympatric carnivores has long been of interest to ecologists. Increased understanding of these interactions can be useful for conservation planning. Increased snowmobile traffic on public lands and in habitats used by Canada lynx (Lynx canadensis) remains controversial due to the concern of coyote (Canis latrans) use of snowmobile trails and potential competition with lynx. Determining the variables influencing coyote use of snowmobile trails has been a priority for managers attempting to conserve lynx and their critical habitat. During 2 winters in northwest Wyoming, we backtracked coyotes for 265 km to determine how varying snow characteristics influenced coyote movements; 278 km of random backtracking was conducted simultaneously for comparison. Despite deep snow (>1 m deep), radio-collared coyotes persisted at high elevations (>2,500 m) year-round. All coyotes used snowmobile trails for some portion of their travel. Coyotes used snowmobile trails for 35% of their travel distance (random: 13%) for a mean distance of 149 m (random: 59 m). Coyote use of snowmobile trails increased as snow depth and penetrability off trails increased. Essentially, snow characteristics were most influential on how much time coyotes spent on snowmobile trails. In the early months of winter, snow depth was low, yet the snow column remained dry and the coyotes traveled off trails. As winter progressed and snow depth increased and snow penetrability increased, coyotes spent more travel distance on snowmobile trails. As spring approached, the snow depth remained high but penetrability decreased, hence coyotes traveled less on snowmobile trails because the snow column off trail was more supportive. Additionally, coyotes traveled closer to snowmobile trails than randomly expected and selected shallower snow when traveling off trails. Coyotes also preferred using snowmobile trails to access ungulate kills. Snow compaction from winter recreation influenced coyote

The influence of snowmobile trails on coyote movements during winter in high-elevation landscapes.

PubMed

Gese, Eric M; Dowd, Jennifer L B; Aubry, Lise M

2013-01-01

Competition between sympatric carnivores has long been of interest to ecologists. Increased understanding of these interactions can be useful for conservation planning. Increased snowmobile traffic on public lands and in habitats used by Canada lynx (Lynx canadensis) remains controversial due to the concern of coyote (Canis latrans) use of snowmobile trails and potential competition with lynx. Determining the variables influencing coyote use of snowmobile trails has been a priority for managers attempting to conserve lynx and their critical habitat. During 2 winters in northwest Wyoming, we backtracked coyotes for 265 km to determine how varying snow characteristics influenced coyote movements; 278 km of random backtracking was conducted simultaneously for comparison. Despite deep snow (>1 m deep), radio-collared coyotes persisted at high elevations (>2,500 m) year-round. All coyotes used snowmobile trails for some portion of their travel. Coyotes used snowmobile trails for 35% of their travel distance (random: 13%) for a mean distance of 149 m (random: 59 m). Coyote use of snowmobile trails increased as snow depth and penetrability off trails increased. Essentially, snow characteristics were most influential on how much time coyotes spent on snowmobile trails. In the early months of winter, snow depth was low, yet the snow column remained dry and the coyotes traveled off trails. As winter progressed and snow depth increased and snow penetrability increased, coyotes spent more travel distance on snowmobile trails. As spring approached, the snow depth remained high but penetrability decreased, hence coyotes traveled less on snowmobile trails because the snow column off trail was more supportive. Additionally, coyotes traveled closer to snowmobile trails than randomly expected and selected shallower snow when traveling off trails. Coyotes also preferred using snowmobile trails to access ungulate kills. Snow compaction from winter recreation influenced coyote

On the onset of surface condensation: formation and transition mechanisms of condensation mode

PubMed Central

Sheng, Qiang; Sun, Jie; Wang, Qian; Wang, Wen; Wang, Hua Sheng

2016-01-01

Molecular dynamics simulations have been carried out to investigate the onset of surface condensation. On surfaces with different wettability, we snapshot different condensation modes (no-condensation, dropwise condensation and filmwise condensation) and quantitatively analyze their characteristics by temporal profiles of surface clusters. Two different types of formation of nanoscale droplets are identified, i.e. the formations with and without film-like condensate. We exhibit the effect of surface tensions on the formations of nanoscale droplets and film. We reveal the formation mechanisms of different condensation modes at nanoscale based on our simulation results and classical nucleation theory, which supplements the ‘classical hypotheses’ of the onset of dropwise condensation. We also reveal the transition mechanism between different condensation modes based on the competition between surface tensions and reveal that dropwise condensation represents the transition states from no-condensation to filmwise condensation. PMID:27481071

On the onset of surface condensation: formation and transition mechanisms of condensation mode.

PubMed

Sheng, Qiang; Sun, Jie; Wang, Qian; Wang, Wen; Wang, Hua Sheng

2016-08-02

Molecular dynamics simulations have been carried out to investigate the onset of surface condensation. On surfaces with different wettability, we snapshot different condensation modes (no-condensation, dropwise condensation and filmwise condensation) and quantitatively analyze their characteristics by temporal profiles of surface clusters. Two different types of formation of nanoscale droplets are identified, i.e. the formations with and without film-like condensate. We exhibit the effect of surface tensions on the formations of nanoscale droplets and film. We reveal the formation mechanisms of different condensation modes at nanoscale based on our simulation results and classical nucleation theory, which supplements the 'classical hypotheses' of the onset of dropwise condensation. We also reveal the transition mechanism between different condensation modes based on the competition between surface tensions and reveal that dropwise condensation represents the transition states from no-condensation to filmwise condensation.

Trail pheromones: an integrative view of their role in social insect colony organization.

PubMed

Czaczkes, Tomer J; Grüter, Christoph; Ratnieks, Francis L W

2015-01-07

Trail pheromones do more than simply guide social insect workers from point A to point B. Recent research has revealed additional ways in which they help to regulate colony foraging, often via positive and negative feedback processes that influence the exploitation of the different resources that a colony has knowledge of. Trail pheromones are often complementary or synergistic with other information sources, such as individual memory. Pheromone trails can be composed of two or more pheromones with different functions, and information may be embedded in the trail network geometry. These findings indicate remarkable sophistication in how trail pheromones are used to regulate colony-level behavior, and how trail pheromones are used and deployed at the individual level.

Hexyl decanoate, the first trail pheromone compound identified in a stingless bee, Trigona recursa.

PubMed

Jarau, Stefan; Schulz, Claudia M; Hrncir, Michael; Francke, Wittko; Zucchi, Ronaldo; Barth, Friedrich G; Ayasse, Manfred

2006-07-01

Foragers of many species of stingless bees guide their nestmates to food sources by means of scent trails deposited on solid substrates between the food and the nest. The corresponding trail pheromones are generally believed to be produced in the mandibular glands, although definitive experimental proof has never been provided. We tested the trail following behavior of recruits of Trigona recursa in field experiments with artificial scent trails branching off from natural scent trails of this stingless bee. First-time recruits (newcomers) did not follow these trails when they were laid with pure solvent or mandibular gland extract. However, they did follow trails made with labial gland extract. Chemical analyses of labial gland secretions revealed that hexyl decanoate was the dominant component (72.4 +/- 1.9% of all volatiles). Newcomers were significantly attracted to artificial trails made with synthetic hexyl decanoate, demonstrating its key function in eliciting scent-following behavior. According to our experiments with T. recursa, the trail pheromone is produced in the labial glands and not in the mandibular glands. Hexyl decanoate is the first component of a trail pheromone identified and proved to be behaviorally active in stingless bees.

Female Sex Pheromone in Trails of the Minute Pirate Bug, Orius minutus (L).

PubMed

Maeda, Taro; Fujiwara-Tsujii, Nao; Yasui, Hiroe; Matsuyama, Shigeru

2016-05-01

Orius minutus (L.) (Heteroptera: Anthocoridae) is a natural enemy of agricultural pests such as thrips, aphids, and various newly hatched insect juveniles. In this study, we conducted 1) behavioral assays for evidence of contact sex pheromone activity in trails of O. minutus, and 2) chemical analysis to identify the essential chemical components of the trails. Males showed arrestment to trails of mature virgin females but not to trails from either conspecific nymphs or immature females. Females also showed arrestment to trails from conspecific males, although the response was weaker than that exhibited by males. The activity of female trails lasted for at least 46 h after deposition. Males showed a response irrespective of mating experience. Following confirmation that a contact sex pheromone was present in the trails of female O. minutus, we used a bioassay-driven approach to isolate the active chemicals. After fractionation on silica gel, the n-hexane fraction was found to be biologically active to males. A major compound in the active fraction was (Z)-9-nonacosene; this compound was found only in trail extracts of mature virgin females. Synthetic (Z)-9-nonacosene arrested O. minutus males, indicating that it is the major active component of the contact sex pheromone in the trails of female O. minutus.

Sediment pathways in a tropical forest: effects of logging roads and skid trails

NASA Astrophysics Data System (ADS)

Sidle, Roy C.; Sasaki, Shozo; Otsuki, Mieko; Noguchi, Shoji; Rahim Nik, Abdul

2004-03-01

Significant erosion occurred from recently constructed forest logging roads and skid trails in a small headwater catchment in Peninsular Malaysia. Soil loss was estimated by measuring dimensions of all significant rills and gullies along the road, as well as by measuring height of preserved soil pedestals in sidecast and fill material and on skid trails. Estimates of surface erosion from logging roads and skid trails were 272 +/- 20 t ha-1 year-1 and 275 +/- 20 t ha-1 year-1 respectively. However, owing to lack of connectivity of skid trails to the stream, much of the sediment mobilized on skid trails was stored either on adjacent hillslopes or the trails themselves, rather than being transported to the stream system, as was the case for the road. Steeper skid trails (>20% gradient) had slightly higher erosion rates (320 +/- 24 t ha-1 year-1) than trails with gentler gradients (245-264 t ha-1 year-1). Some 60% of the soil loss on logging roads comes from erosion of the running surface. Disturbed cut and fill material along the road supplied the remaining 40% of the soil loss from roads. Roads and skid trails had no designed drainage systems; runoff discharged onto the hillslope at 25 major discharge nodes from the logging road (690 m total length) and at 34 nodes from skid trails (2300 m). Sediment pathways were either fully or moderately connected to headwater channels at 64% of the logging road nodes, but at only 26% of the nodes emanating from skid trails. A detailed sediment budget revealed that 78% of the soil loss from the road system (including log landings) was delivered to the stream in the first 16 months after logging began. Most (90%) of the deposition from skid trails occurred below just three discharge nodes. Runoff from and onto skid trails often exacerbated the sediment connectivity to channels. Clearly, sediment discharge from logging roads was more highly connected to the stream than discharge from skid trails. Once in the channel, much of this

Static Extended Trailing Edge for Lift Enhancement: Experimental and Computational Studies

NASA Technical Reports Server (NTRS)

Liu, Tianshu; Montefort; Liou, William W.; Pantula, Srinivasa R.; Shams, Qamar A.

2007-01-01

A static extended trailing edge attached to a NACA0012 airfoil section is studied for achieving lift enhancement at a small drag penalty. It is indicated that the thin extended trailing edge can enhance the lift while the zero-lift drag is not significantly increased. Experiments and calculations are conducted to compare the aerodynamic characteristics of the extended trailing edge with those of Gurney flap and conventional flap. The extended trailing edge, as a simple mechanical device added on a wing without altering the basic configuration, has a good potential to improve the cruise flight efficiency.

Trail and arena marking by caterpillars ofArchips cerasivoranus (lepidoptera: Tortricidae).

PubMed

Fitzgerald, T D

1993-07-01

The activity ofArchips cerasivoranus caterpillars is largely limited to their colonial silk web and trails. Silk pulled directly from the spinnerets of caterpillars and wound onto paper strips to form artificial trails elicited locomotion from the larvae. Trails made from extracts of silk and silk glands also elicited locomotion. These and other observations reported here indicate that the caterpillars are responsive to a water-soluble pheromone that is a component of the silk strand. Marker pheromones appear not to be secreted from other regions of the body, as has been reported for some other trail-following caterpillars.

Estimating soil erosion on hiking trails in the Sierra Mariola Natural Park in southern Spain

NASA Astrophysics Data System (ADS)

Magdalena Warter, Maria; Peeters, Mattias; Kuppen, Emiel; Blok, Kas; Dilly, Lina

2017-04-01

Natural parks and protected natural areas provide excellent recreational opportunities for outdoor activities through the richness of the natural environment and the abundance of walking trails. Hiking, mountain biking and running have rapidly gained popularity over recent years increasing concerns about the erosion and degradation of hiking trails caused by (over)use. This is also the case in the Sierra Mariola Natural Park in southeast Spain, which is a popular destination for tourists due to its diverse fauna and flora. The increasing number of tourists together with the negative impacts of climate change necessitates a better understanding of the key soil erosion processes impacting hiking trails. There are 4 scenic trail routes in the Natural Park amounting to 21 km plus an additional network of unofficial trails. Apart from the heavy touristic traffic on the trails there are large trail running events with up to 1000 participants becoming increasingly popular, however local park authorities have voiced concerns about the impacts of these activities on the trails. Despite the popularity of walking trails around the world, there is a paucity of research exploring soil erosion from these features. Therefore, the aims of this study are: 1) to ascertain the amount of erosion that occurs on trails in the Sierra Mariola Natural Park, and 2) determine the key factors that influence soil erosion. Some 100 km of trails were evaluated (both official and unmarked trails), with route segments ranging between 2 and 10 km. A trail classification system was developed to group trail segments based on their surface characteristics (bedrock, gravel, mixed sediment, soil or man-made) and specific erosion features (rills, ditch-shaped, tilted). For each class, the average erosion rate was calculated which ranged from 262 t/ha for soil-based trails to 2006 t/ha for heavily eroded, ditch-shaped trails. The spatial distribution of the different erosion rates and trail types were

Modeling and mapping urban bicyclists' preferences for trail environments.

Treesearch

Dawn Wiberg-Carlson; Herbert Schroeder

1992-01-01

Derives a model for predicting preferences of seventh and eighth graders for settings along an urban bicycle trail. The rises and falls in preference along the length of the trail are profiled and mapped to display the areas of highest and lowest perceived quality.

Is the color trails culture free?

PubMed

Fasfous, Ahmed F; Puente, Antonio E; Pérez-Marfil, María Nieves; Cruz-Quintana, Francisco; Peralta-Ramirez, Isabel; Pérez-García, Miguel

2013-11-01

Increasingly clinical neuropsychology has been addressing the effects of culture on neuropsychological functioning. However, that focus has been on comparing performance on standardized tests across two or more groups, often Hispanic. In this study, Arabic children were tested in Morocco using a "culture-free test," Children's Color Trails. Children of different ages and living in rural and urban centers were tested. The results suggest that the Color Trails Test scores from Arab children differed from U.S. norms available. Furthermore, the location of testing and the age of the child were of significance. The role of culture-specific tests was considered.

Studies of turbulent round jets through experimentation, simulation, and modeling

NASA Astrophysics Data System (ADS)

Keedy, Ryan

This thesis studies the physics of the turbulent round jet. In particular, it focuses on three different problems that have the turbulent round jet as their base flow. The first part of this thesis examines a compressible turbulent round jet at its sonic condition. We investigate the shearing effect such a jet has when impinging on a solid surface that is perpendicular to the flow direction. We report on experiments to evaluate the jet's ability to remove different types of explosive particles from a glass surface. Theoretical analysis revealed trends and enabled modeling to improve the predictability of particle removal for various jet conditions. The second part of thesis aims at developing a non-intrusive measurement technique for free-shear turbulent flows in nature. Most turbulent jet investigations in the literature, both in the laboratory and in the field, required specialized intrusive instrumentation and/or complex optical setups. There are many situations in naturally-occurring flows where the environment may prove too hostile or remote for existing instrumentation. We have developed a methodology for analyzing video of the exterior of a naturally-occurring flow and calculating the flow velocity. We found that the presence of viscosity gradients affects the velocity analysis. While these effects produce consistent, predictable changes, we became interested in the mechanism by which the viscosity gradients affect the mixing and development of the turbulent round jet. We conducted a stability analysis of the axisymmetric jet when a viscosity gradient is present. Finally, the third problem addressed in this thesis is the growth of liquid droplets by condensation in a turbulent round jet. A vapor-saturated turbulent jet issues into a cold, dry environment. The resulting mixing produces highly inhomogeneous regions of supersaturation, where droplets grow and evaporate. Non-linear interactions between the droplet growth rate and the supersaturation field make

Rock Levitation by Water and Ice; an Explanation for Trails in Racetrack Playa, California

NASA Astrophysics Data System (ADS)

Kletetschka, G.; Ryan, A.; McKinney, E.; Fercana, G.; Schwebler, K. P.; McIntire, L.; Miller, D.; Fox, V. K.; Marbourg, J. M.; Naquin, C. A.; Krzykowski, M.; Wilde, J. R.; Kopp, E. S.; Romine, G.; Yawn, K.; Schoch, I.; McAdam, M.; Burger, D.; Rilee, K.; Jackson, B. K.; Parsons, A. M.; Cheung, C. Y.; Lunar; Planetary Science Academy

2010-12-01

Through a process that is nearly a century-old mystery, rock fragments race over a desiccated layer of sediment in the California desert, forming the infamous rock trails of the Racetrack playa, found in Death Valley, California. Rocks, randomly distributed over the playa, have indented grooves or trails next to them, appearing as if someone had dragged them over the playa surface when wet. Interestingly, no one has ever witnessed the movement of these rocks. Furthermore, the mechanism responsible for these trails behind the rocks has not yet been explained. Rocks have masses ranging from 0.5 kg to 300 kg, and the trails have a chaotic character, with some trails as long as 1/2 km. Each rock has a mound of raised clay on one side and a mud trail on the other; no other unusual marks are visible. A number of trails have no rocks at the end, with only a mound of solid clay where a rock once appeared to be, as if something was pushing the clay forwards to make the trail but disappeared after the trail was made. Measurements of the humidity and temperature of the sediment pointed towards a unique mechanism of how the trails could form on their own and how simple environmental changes could result in the aforementioned trails in the sediment.

Accurate Natural Trail Detection Using a Combination of a Deep Neural Network and Dynamic Programming.

PubMed

Adhikari, Shyam Prasad; Yang, Changju; Slot, Krzysztof; Kim, Hyongsuk

2018-01-10

This paper presents a vision sensor-based solution to the challenging problem of detecting and following trails in highly unstructured natural environments like forests, rural areas and mountains, using a combination of a deep neural network and dynamic programming. The deep neural network (DNN) concept has recently emerged as a very effective tool for processing vision sensor signals. A patch-based DNN is trained with supervised data to classify fixed-size image patches into "trail" and "non-trail" categories, and reshaped to a fully convolutional architecture to produce trail segmentation map for arbitrary-sized input images. As trail and non-trail patches do not exhibit clearly defined shapes or forms, the patch-based classifier is prone to misclassification, and produces sub-optimal trail segmentation maps. Dynamic programming is introduced to find an optimal trail on the sub-optimal DNN output map. Experimental results showing accurate trail detection for real-world trail datasets captured with a head mounted vision system are presented.

TRAIL Enhances Shikonin Induced Apoptosis through ROS/JNK Signaling in Cholangiocarcinoma Cells.

PubMed

Zhou, Guangyao; Yang, Zuqin; Wang, Xiaodong; Tao, Ran; Zhou, Yuanping

2017-01-01

Cholangiocarcinoma (CCA), arising from varying locations within the biliary tree, is the second most common primary liver malignancy worldwide. Shikonin, an active compound extracted from the Chinese herb Zicao, holds anti-bacterial, anti-inflammatory, and anti-tumor activities. However, the effect of shikonin on human cholangiocarcinoma and detailed mechanisms of TRAIL enhancement remains to be elucidated. The purpose of the study was to investigate the protective functions of TRAIL enhancement for shikonin induced apoptosis in cholangiocarcinoma cells. We use MTT assay, apoptosis assay, caspase activity assay, flow cytometry assay, real time PCR and Western blot to observe the effects of TRAIL on shikonin induced cholangiocarcinoma cells apoptosis and its mechanism. Shikonin inhibited cell viability and induced apoptosis of CCA cells, effects enhanced by TRAIL treatment via activation of caspase-3, -8, -9. Furhermore, TRAIL enhanced anti-proliferation of shikonin and shikonin induced apoptosis through induction of ROS mediated JNK activation, while AKT activation had an effect on shikonin anti-proliferation activity, but not in the TRAIL enhanced counterparts. Finally, shikonin upregulated DR5 expression, an effect essential for TRAIL-enhanced activities of shikonin in RBE cells. Our results revealed that shikonin could inhibit cells viability and induce apoptosis of CCA cells, effects enhanced by TRAIL treatment via ROS mediated JNK signalling pathways, involving up-regulation of DR5 expression. Our results provide further insight into the mechanism underlying the anti-tumor effects of shikonin by TRAIL enhanced in CCA and a new therapeutic strategy to CCA treatment. © 2017 The Author(s). Published by S. Karger AG, Basel.

Scent trailing by virgin females ofPseudococcm calceolariae.

PubMed

Rotundo, G; Tremblay, E

1981-01-01

Virgin females of the citrophilous mealybugPseudococcus calceolariae (Mask.) deposit scent marks as trails on the substrate on which they rest or move. These substances elicit attraction and sexual behavior by conspecific males. The same responses were obtained when males were bioassayed on extracts from filter paper disks on which females had rested. The significance of scent trailing in mealybugs is discussed.

Cohort Profile Update: The TRacking Adolescents’ Individual Lives Survey (TRAILS)

PubMed Central

Oldehinkel, Albertine J; Rosmalen, Judith GM; Buitelaar, Jan K; Hoek, Hans W; Ormel, Johan; Raven, Dennis; Reijneveld, Sijmen A; Veenstra, René; Verhulst, Frank C; Vollebergh, Wilma AM; Hartman, Catharina A

2015-01-01

TRAILS consists of a population cohort (N = 2230) and a clinical cohort (N = 543), both of which were followed from about age 11 years onwards. To date, the population cohort has been assessed five times over a period of 11 years, with retention rates ranging between 80% and 96%. The clinical cohort has been assessed four times over a period of 8 years, with retention rates ranging between 77% and 85%. Since the IJE published a cohort profile on the TRAILS in 2008, the participants have matured from adolescents into young adults. The focus shifted from parents and school to entry into the labour market and family formation, including offspring. Furthermore, psychiatric diagnostic interviews were administered, the database was linked to a Psychiatric Case Registry, and the availability of genome-wide SNP variations opened the door to genome-wide association studies regarding a wide range of (endo)phenotypes. With some delay, TRAILS data are available to researchers outside the TRAILS consortium without costs; access can be obtained by submitting a publication proposal (see www.trails.nl). PMID:25431468

30 CFR 75.907 - Design of trailing cables for medium-voltage circuits.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Design of trailing cables for medium-voltage... Medium-Voltage Alternating Current Circuits § 75.907 Design of trailing cables for medium-voltage circuits. [Statutory Provisions] Trailing cables for medium-voltage circuits shall include grounding...

30 CFR 75.907 - Design of trailing cables for medium-voltage circuits.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Design of trailing cables for medium-voltage... Medium-Voltage Alternating Current Circuits § 75.907 Design of trailing cables for medium-voltage circuits. [Statutory Provisions] Trailing cables for medium-voltage circuits shall include grounding...

30 CFR 75.907 - Design of trailing cables for medium-voltage circuits.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Design of trailing cables for medium-voltage... Medium-Voltage Alternating Current Circuits § 75.907 Design of trailing cables for medium-voltage circuits. [Statutory Provisions] Trailing cables for medium-voltage circuits shall include grounding...

30 CFR 75.907 - Design of trailing cables for medium-voltage circuits.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Design of trailing cables for medium-voltage... Medium-Voltage Alternating Current Circuits § 75.907 Design of trailing cables for medium-voltage circuits. [Statutory Provisions] Trailing cables for medium-voltage circuits shall include grounding...

30 CFR 75.907 - Design of trailing cables for medium-voltage circuits.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Design of trailing cables for medium-voltage... Medium-Voltage Alternating Current Circuits § 75.907 Design of trailing cables for medium-voltage circuits. [Statutory Provisions] Trailing cables for medium-voltage circuits shall include grounding...

Quantum Many-Body Dynamics with Driven Bose Condensates: Kibble-Zurek Mechanism and Bose Fireworks

NASA Astrophysics Data System (ADS)

Clark, Logan William

finite quasimomentum. We measured the growth of these domains over time and the correlation functions describing their spatial distribution by directly reconstructing the quasimomentum distribution. We observed the expected scaling laws across more than an order of magnitude in the crossing rate, aside from which the observed critical dynamics were indeed independent of the crossing rate. These experiments provide strong support for the universal scaling symmetry of space and time and the extension of the Kibble-Zurek mechanism to quantum phase transitions. We also present the first observation of Bose Fireworks: the sudden emission of many bright, narrow jets of atoms from condensates with oscillating interaction strength. Even though the underlying inelastic s-wave collisions induced by oscillating interactions are isotropic, the collective nature of collisions in the condensate causes the outgoing bosonic atoms to bunch into narrow jets in the horizontal plane. This bunching results from runaway stimulated collisions, which we find can only occur above a threshold oscillation amplitude. The observed atom number in the jets suggests that they are seeded by quantum fluctuations. Moreover, in azimuthal correlation functions we observe forward correlations consistent with theory, which saturate the limit from the uncertainty principle. We also observe partial correlation between counterpropagating jets. Bose Fireworks provide a well-controlled platform for understanding the diverse class of systems in which a coherent source rapidly emits pairs of counterpropagating bosons.

Observations of Aircraft Dissipation Trails from GOES

NASA Technical Reports Server (NTRS)

Duda, David P.; Minnis, Patrick

2002-01-01

Two cases of distrails (aircraft dissipation trails) with associated fall streak clouds were analyzed using multispectral geostationary satellite data. One distrail was observed on 23 July 2000 in a single cloud layer over southeastern Virginia and the Chesapeake Bay. Another set of trails developed on 6 January 2000 at the top of multilayer clouds off the coasts of Georgia and South Carolina. The distrails on both days formed in optically thin, midlevel stratified clouds with cloud-top heights between 7.6 and 9.1 km. The distrail features remained intact and easily visible from satellite images for 1-2 h in spite of winds near 50 km at cloud level. The width of the distrails spread as far as 20 km within 90 min or less. Differences between the optical properties of the clouds surrounding the trails and those of the fall streak particles inside the distrails allowed for easy identification of the fall streak clouds in either the 3.9-micrometer brightness temperature imagery, or the 10.7-micrometer - 12.0-micrometer brightness temperature difference. Although the three-channel infrared retrieval was better at retrieving cloud properties in the multilayer cloud case, two independent remote sensing retrievals of both distrail cases showed that the fall streaks had larger particle sizes than the clouds outside of the trails.

Influence of TRAIL gene on biomechanical properties of the human leukemic cell line Jurkat.

PubMed

Yao, Weijuan; Chen, Kai; Wang, Xinjuan; Xie, Lide; Wen, Zongyao; Yan, Zongyi; Chien, Shu

2002-12-01

We cloned the cDNA fragment of human TNF-related apoptosis inducing ligand (TRAIL) into RevTet-On, a Tet-regulated and high-level gene expression system. Making use of the TRAIL gene expression system in Jurkat as a cell model, we studied the influence of TRAIL gene on the biomechanics properties of Jurkat through measuring changes of cellular biomechanics properties before and after the TRAIL gene expression, which was induced by adding tetracycline derivative doxycycline (Dox). The results indicated that the TRAIL gene expression led to significant changes in cellular biomechanics properties. The osmotic fragility increased and the cell stiffness increased after the expression of TRAIL gene. Thus, the apoptosis-inducing TRAIL gene caused significant changes in the biomechanics properties of Jurkat cells.

7. SHOWING METHOD OF SLEDDING WIND CABLE DOWN YAKI TRAIL ...

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

7. SHOWING METHOD OF SLEDDING WIND CABLE DOWN YAKI TRAIL TO THE BRIDGE, WEIGHT OF CABLE AND DRUM APPROXIMATELY 2200 POUNDS - Kaibab Trail Suspension Bridge, Spanning Colorado River, Grand Canyon, Coconino County, AZ

Mixing of Multiple Jets with a Confined Subsonic Crossflow. Part 2; Opposed Rows of Orifices in Rectangular Ducts

NASA Technical Reports Server (NTRS)

Holdeman, J. D.; Liscinsky, D. S.; Bain, D. B.

1999-01-01

This paper summarizes experimental and computational results on the mixing of opposed rows of jets with a confined subsonic crossflow in rectangular ducts. The studies from which these results were excerpted investigated flow and geometric variations typical of the complex three-dimensional flowfield in the combustion chambers in gas turbine engines. The principal observation was that the momentum-flux ratio, J, and the orifice spacing, S/H, were the most significant flow and geometric variables. Jet penetration was critical, and penetration decreased as either momentum-flux ratio or orifice spacing decreased. It also appeared that jet penetration remained similar with variations in orifice size, shape, spacing, and momentum-flux ratio when the orifice spacing was inversely proportional to the square-root of the momentum-flux ratio. It was also seen that planar averages must be considered in context with the distributions. Note also that the mass-flow ratios and the orifices investigated were often very large (jet-to-mainstream mass-flow ratio > 1 and the ratio of orifices-area-to-mainstream- cross-sectional-area up to 0.5, respectively), and the axial planes of interest were often just downstream of the orifice trailing edge. Three-dimensional flow was a key part of efficient mixing and was observed for all configurations.

Mixing of Multiple Jets With a Confined Subsonic Crossflow. Part 2; Opposed Rows of Orifices in Rectangular Ducts

NASA Technical Reports Server (NTRS)

Holdeman, James D.; Liscinsky, David S.; Bain, Daniel B.

1997-01-01

This paper summarizes experimental and computational results on the mixing of opposed rows of jets with a confined subsonic crossflow in rectangular ducts. The studies from which these results were excerpted investigated flow and geometric variations typical of the complex 3-D flowfield in the combustion chambers in gas turbine engines. The principal observation was that the momentum-flux ratio, J, and the orifice spacing, S/H, were the most significant flow and geometric variables. Jet penetration was critical, and penetration decreased as either momentum-flux ratio or orifice spacing decreased. It also appeared that jet penetration remained similar with variations in orifice size, shape, spacing, and momentum-flux ratio when the orifice spacing was inversely proportional to the square-root of the momentum-flux ratio. It was also seen that planar averages must be considered in context with the distributions. Note also that the mass-flow ratios and the offices investigated were often very large (jet-to-mainstream mass-flow ratio greater than 1 and the ratio of orifices-area-to-mainstream-cross-sectional-area up to 0.5 respectively), and the axial planes of interest were often just downstream of the orifice trailing edge. Three-dimensional flow was a key part of efficient mixing and was observed for all configurations.

Fiscal Year 2013 Trails Management Program Mitigation Action Plan Annual Report, October 2013

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

Pava, Daniel S.

This Trails Management Program Mitigation Action Plan Annual Report (Trails MAPAR) has been prepared for the Department of Energy (DOE)/National Nuclear Security Administration (NNSA) as part of implementing the 2003 Final Environmental Assessment for the Proposed Los Alamos National Laboratory Trails Management Program (DOE 2003). The Trails Mitigation Action Plan (MAP) is now a part of the Site-Wide Environmental Impact Statement for the Continued Operation of Los Alamos National Laboratory (DOE/EIS 0380) Mitigation Action Plan (2008 SWEIS MAP) (DOE 2008). The MAP provides guidance for the continued implementation of the Trails Management Program at Los Alamos National Laboratory (LANL) andmore » integration of future mitigation actions into the 2008 SWEIS MAP to decrease impacts associated with recreational trails use at LANL. This eighth MAPAR includes a summary of Trails Management Program activities and actions during Fiscal Year (FY) 2013, from October 2012 through September 2013.« less

Stingless bees (Scaptotrigona pectoralis) learn foreign trail pheromones and use them to find food.

PubMed

Reichle, Christian; Aguilar, Ingrid; Ayasse, Manfred; Jarau, Stefan

2011-03-01

Foragers of several species of stingless bees (Hymenoptera, Apidae and Meliponini) deposit pheromone marks in the vegetation to guide nestmates to new food sources. These pheromones are produced in the labial glands and are nest and species specific. Thus, an important question is how recruited foragers recognize their nestmates' pheromone in the field. We tested whether naïve workers learn a specific trail pheromone composition while being recruited by nestmates inside the hive in the species Scaptotrigona pectoralis. We installed artificial scent trails branching off from trails deposited by recruiting foragers and registered whether newly recruited bees follow these trails. The artificial trails were baited with trail pheromones of workers collected from foreign S. pectoralis colonies. When the same foreign trail pheromone was presented inside the experimental hives while recruitment took place a significant higher number of bees followed the artificial trails than in experiments without intranidal presentation. Our results demonstrate that recruits of S. pectoralis can learn the composition of specific trail pheromone bouquets inside the nest and subsequently follow this pheromone in the field. We, therefore, suggest that trail pheromone recognition in S. pectoralis is based on a flexible learning process rather than being a genetically fixed behaviour.

Multi-scale study of condensation in water jets using ellipsoidal-statistical Bhatnagar-Gross-Krook and molecular dynamics modeling

NASA Astrophysics Data System (ADS)

Li, Zheng; Borner, Arnaud; Levin, Deborah A.

2014-06-01

Homogeneous water condensation and ice formation in supersonic expansions to vacuum for stagnation pressures from 12 to 1000 mbar are studied using the particle-based Ellipsoidal-Statistical Bhatnagar-Gross-Krook (ES-BGK) method. We find that when condensation starts to occur, at a stagnation pressure of 96 mbar, the increase in the degree of condensation causes an increase in the rotational temperature due to the latent heat of vaporization. The simulated rotational temperature profiles along the plume expansion agree well with measurements confirming the kinetic homogeneous condensation models and the method of simulation. Comparisons of the simulated gas and cluster number densities, cluster size for different stagnation pressures along the plume centerline were made and it is found that the cluster size increase linearly with respect to stagnation pressure, consistent with classical nucleation theory. The sensitivity of our results to cluster nucleation model and latent heat values based on bulk water, specific cluster size, or bulk ice are examined. In particular, the ES-BGK simulations are found to be too coarse-grained to provide information on the phase or structure of the clusters formed. For this reason, molecular dynamics simulations of water condensation in a one-dimensional free expansion to simulate the conditions in the core of a plume are performed. We find that the internal structure of the clusters formed depends on the stagnation temperature. A larger cluster of average size 21 was tracked down the expansion, and a calculation of its average internal temperature as well as a comparison of its radial distribution functions (RDFs) with values measured for solid amorphous ice clusters lead us to conclude that this cluster is in a solid-like rather than liquid form. In another molecular-dynamics simulation at a much lower stagnation temperature, a larger cluster of size 324 and internal temperature 200 K was extracted from an expansion plume and

Laboratory investigations of the trail-following responses of four species of leaf-cutting ants with notes on the specificity of a trail pheromone of Atta texana (Buckley)

Treesearch

S. W. Robinson; John C. Moser; M. S. Blum; E. Amante

1974-01-01

Interspecific trail following activity of poison sac contents from four species of leaf-cutting ants was investigated. with only one exception, all the species teste followed trails made from each others poison sac contents. however when the ants were given a choice of following one of two separate trails, clear differences were shown in the poison sac contents of the...

5. Roaring Fork Motor Nature Trail, vista at stop three. ...

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

5. Roaring Fork Motor Nature Trail, vista at stop three. - Great Smoky Mountains National Park Roads & Bridges, Roaring Fork Motor Nature Trail, Between Cherokee Orchard Road & U.S. Route 321, Gatlinburg, Sevier County, TN

Metformin sensitizes triple-negative breast cancer to proapoptotic TRAIL receptor agonists by suppressing XIAP expression.

PubMed

Strekalova, Elena; Malin, Dmitry; Rajanala, Harisha; Cryns, Vincent L

2017-06-01

Despite robust antitumor activity in diverse preclinical models, TNF-related apoptosis-inducing ligand (TRAIL) receptor agonists have not demonstrated efficacy in clinical trials, underscoring the need to identify agents that enhance their activity. We postulated that the metabolic stress induced by the diabetes drug metformin would sensitize breast cancer cells to TRAIL receptor agonists. Human triple (estrogen receptor, progesterone receptor, and HER2)-negative breast cancer (TNBC) cell lines were treated with TRAIL receptor agonists (monoclonal antibodies or TRAIL peptide), metformin, or the combination. The effects on cell survival, caspase activation, and expression of TRAIL receptors and the antiapoptotic protein XIAP were determined. In addition, XIAP was silenced by RNAi in TNBC cells and the effects on sensitivity to TRAIL were determined. The antitumor effects of metformin, TRAIL, or the combination were evaluated in an orthotopic model of metastatic TNBC. Metformin sensitized diverse TNBC cells to TRAIL receptor agonists. Metformin selectively enhanced the sensitivity of transformed breast epithelial cells to TRAIL receptor agonist-induced caspase activation and apoptosis with little effect on untransformed breast epithelial cells. These effects of metformin were accompanied by robust reductions in the protein levels of XIAP, a negative regulator of TRAIL-induced apoptosis. Silencing XIAP in TNBC cells mimicked the TRAIL-sensitizing effects of metformin. Metformin also enhanced the antitumor effects of TRAIL in a metastatic murine TNBC model. Our findings indicate that metformin enhances the activity of TRAIL receptor agonists, thereby supporting the rationale for additional translational studies combining these agents.

Expression of TRAIL and Fas in Primary Hyperparathyroidism.

PubMed

Segiet, Oliwia Anna; Deska, Mariusz; Mielańczyk, Łukasz; Brzozowa-Zasada, Marlena; Buła, Grzegorz; Gawrychowski, Jacek; Wojnicz, Romuald

2017-08-01

Differentiating between parathyroid lesions is still difficult and ambiguous. In cases of primary hyperparathyroidism, appropriate and prompt diagnosis is of great importance for effective treatment and follow-up. A great amount of mechanisms contribute to the pathogenesis of primary hyperparathyroidism, such as disturbance in balance between pro- and anti-apoptotic factors. Therefore, we examined whether immunohistochemical expression of apoptotic factors, TNF-related apoptosis-inducing ligand (TRAIL) and Fas, could have clinical utility as a marker of proliferative lesions of parathyroid gland. Parathyroid specimens of 58 consecutive patients who had undertaken surgery due to primary hyperparathyroidism were incubated with purified mouse monoclonal antihuman antibodies: anti-TRAIL and anti-Fas. Staining was considered positive when at least 5% of the cells showed immunoreactivity. The percentage of cells which were positively stained for TRAIL in parathyroid hyperplasia was 9.65%, in parathyroid adenoma 8.31%, and in normal controls 2.24%. Immunoreactivity for TRAIL was detected in 91.89% of parathyroid hyperplasias, 85.71% of parathyroid adenomas, and none in healthy glands. The percentage of cells with a positive reaction to Fas in parathyroid hyperplasia was 8.92%, in parathyroid adenoma 8.09%, and in normal tissue 1.9%. The expression of Fas was found in 94.59% of parathyroid hyperplasias, 90.48% of parathyroid adenomas, and none in healthy glands. In our study, hyperplasias demonstrated the highest expression of TRAIL and Fas, whereas in adenomas it was increased compared to normal tissue, but lower than in hyperplasias. These factors could be an additive tool in the differential diagnosis of parathyroid lesions.

77 FR 29624 - Cheniere Creole Trail Pipeline, L.P.; Notice of Application

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-18

... Creole Trail Pipeline, L.P.; Notice of Application Take notice that on April 30, 2012, Cheniere Creole Trail Pipeline, L.P. (Cheniere), 700 Milam, Suite 800, Houston, TX 77002, filed an application in Docket... Creole Trail Expansion Project (Project). Cheniere's Project would consist of construction of a new 53...

36 CFR 212.55 - Criteria for designation of roads, trails, and areas.

Code of Federal Regulations, 2011 CFR

2011-07-01

... roads, trails, and areas. 212.55 Section 212.55 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE TRAVEL MANAGEMENT Designation of Roads, Trails, and Areas for Motor Vehicle Use § 212.55 Criteria for designation of roads, trails, and areas. (a) General criteria for designation of...

7. Roaring Fork Motor Nature Trail, rocks along edge of ...