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1

Analyzing the Impacts of Off-Road Vehicle (ORV) Trails on Watershed Processes in Wrangell-St. Elias National Park and Preserve, Alaska  

NASA Astrophysics Data System (ADS)

Trails created by off-road vehicles (ORV) in boreal lowlands are known to cause local impacts, such as denuded vegetation, soil erosion, and permafrost thaw, but impacts on stream and watershed processes are less certain. In Wrangell-St. Elias National Park and Preserve (WRST), Alaska, ORV trails have caused local resource damage in intermountain lowlands with permafrost soils and abundant wetlands and there is a need to know whether these impacts are more extensive. Comparison of aerial photography from 1957, 1981, and 2004 coupled with ground surveys in 2009 reveal an increase in trail length and number and show an upslope expansion of a trail system around points of stream channel initiation. We hypothesized that these impacts could also cause premature initiation and headward expansion of channels because of lowered soil resistance and greater runoff accumulation as trails migrate upslope. Soil monitoring showed earlier and deeper thaw of the active layer in and adjacent to trails compared to reference sites. Several rainfall-runoff events during the summer of 2009 showed increased and sustained flow accumulation below trail crossings and channel shear forces sufficient to cause headward erosion of silt and peat soils. These observations of trail evolution relative to stream and wetland crossings together with process studies suggest that ORV trails are altering watershed processes. These changes in watershed processes appear to result in increasing drainage density and may also alter downstream flow regimes, water quality, and aquatic habitat. Addressing local land-use disturbances in boreal and arctic parklands with permafrost soils, such as WRST, where responses to climate change may be causing concurrent shifts in watershed processes, represents an important challenge facing resource managers.

Arp, Christopher D.; Simmons, Trey

2012-03-01

2

Evaluating Environmental Impacts of Off-Road Vehicles.  

ERIC Educational Resources Information Center

Discusses a study undertaken to determine the ecological effects of off-road vehicles, such as four-wheel drive trucks and dirt bikes in the Big Cottonwood Canyon area near Salt Lake City. Applications of the study to other investigations of off-road vehicles are discussed. (DB)

Kay, Jeanne; And Others

1981-01-01

3

Spine Trauma Associated with Off-Road Vehicles.  

ERIC Educational Resources Information Center

A seven-year review of 1,447 cases of spine trauma showed that 53 cases were associated with the use of off-road vehicles, such as all-terrain vehicles, snowmobiles, and motorized dirt bikes. The development of safe riding areas, legislation governing safe operation, and public safety education are advised to curb this trend. (Author/JL)

Reid, David C.; And Others

1988-01-01

4

Modeling and validation of off-road vehicle ride dynamics  

NASA Astrophysics Data System (ADS)

Increasing concerns on human driver comfort/health and emerging demands on suspension systems for off-road vehicles call for an effective and efficient off-road vehicle ride dynamics model. This study devotes both analytical and experimental efforts in developing a comprehensive off-road vehicle ride dynamics model. A three-dimensional tire model is formulated to characterize tire-terrain interactions along all the three translational axes. The random roughness properties of the two parallel tracks of terrain profiles are further synthesized considering equivalent undeformable terrain and a coherence function between the two tracks. The terrain roughness model, derived from the field-measured responses of a conventional forestry skidder, was considered for the synthesis. The simulation results of the suspended and unsuspended vehicle models are derived in terms of acceleration PSD, and weighted and unweighted rms acceleration along the different axes at the driver seat location. Comparisons of the model responses with the measured data revealed that the proposed model can yield reasonably good predictions of the ride responses along the translational as well as rotational axes for both the conventional and suspended vehicles. The developed off-road vehicle ride dynamics model could serve as an effective and efficient tool for predicting vehicle ride vibrations, to seek designs of primary and secondary suspensions, and to evaluate the roles of various operating conditions.

Pazooki, Alireza; Rakheja, Subhash; Cao, Dongpu

2012-04-01

5

Banning Off-Road Vehicles from the Nation's Parks  

NSDL National Science Digital Library

On June 9, the US Park Service ordered a ban on snowmobiles in a core area of Denali National Park. This announcement came in the wake of successful public outcry against Off-Road Vehicles (ORVs) -- including the banning of snowmobiles from most US national parks (except Alaska) in late April, and a similar banning of jet skis in late March. At a time when most Americans are parking their fuel-efficient cars in favor of gas-guzzling Sport Utility Vehicles, the recent limitations placed on recreational vehicles are welcomed by many environmentalists. However, other environmental groups are disappointed by what they consider overly mild restrictions. This week's In The News takes a look at the June order and offers information on Off-Road Vehicle use and the US National Park system.

Payne, Laura X.

6

36 CFR 13.1109 - Off-road vehicle use in Glacier Bay National Preserve.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Off-road vehicle use in Glacier Bay National Preserve. 13.1109 ...UNITS IN ALASKA Special Regulations-Glacier Bay National Park and Preserve Administrative...13.1109 Off-road vehicle use in Glacier Bay National Preserve. The use...

2010-07-01

7

36 CFR 13.1109 - Off-road vehicle use in Glacier Bay National Preserve.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Off-road vehicle use in Glacier Bay National Preserve. 13.1109 ...UNITS IN ALASKA Special Regulations-Glacier Bay National Park and Preserve Administrative...13.1109 Off-road vehicle use in Glacier Bay National Preserve. The use...

2012-07-01

8

36 CFR 13.1109 - Off-road vehicle use in Glacier Bay National Preserve.  

Code of Federal Regulations, 2014 CFR

...2014-07-01 false Off-road vehicle use in Glacier Bay National Preserve. 13.1109 ...UNITS IN ALASKA Special Regulations-Glacier Bay National Park and Preserve Administrative...13.1109 Off-road vehicle use in Glacier Bay National Preserve. The use...

2014-07-01

9

36 CFR 13.1109 - Off-road vehicle use in Glacier Bay National Preserve.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Off-road vehicle use in Glacier Bay National Preserve. 13.1109 ...UNITS IN ALASKA Special Regulations-Glacier Bay National Park and Preserve Administrative...13.1109 Off-road vehicle use in Glacier Bay National Preserve. The use...

2013-07-01

10

36 CFR 13.1109 - Off-road vehicle use in Glacier Bay National Preserve.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Off-road vehicle use in Glacier Bay National Preserve. 13.1109 ...UNITS IN ALASKA Special Regulations-Glacier Bay National Park and Preserve Administrative...13.1109 Off-road vehicle use in Glacier Bay National Preserve. The use...

2011-07-01

11

Fugitive dust emissions from off-road vehicle maneuvers on military training lands  

Technology Transfer Automated Retrieval System (TEKTRAN)

Off-road vehicle training can contribute to air quality degradation because of increased wind erosion as a result of soil disruption during high wind events. However, limited information exists regarding the impacts of off-road vehicle maneuvering on wind erosion potential of soils. This study was c...

12

Monitoring and assessing global impacts of roads and off-road vehicle traffic  

Technology Transfer Automated Retrieval System (TEKTRAN)

Rapid increases in the number of vehicles, urban sprawl, exurban development and infrastructure development for energy and water have led to dramatic increases in both the size and extent of the global road network. Anecdotal evidence suggests that off-road vehicle traffic has also increased in many...

13

Fugitive particulate air emissions from off-road vehicle maneuvers at military training lands  

Technology Transfer Automated Retrieval System (TEKTRAN)

Military training lands used for off-road vehicle maneuvers may be subject to severe soil loss and air quality degradation as a result of severe wind erosion. The objective of this study was to measure suspended particulate matter resulting from various different vehicle training scenarios. Soil s...

14

Environmental effects of soil property changes with off-road vehicle use  

Microsoft Academic Search

The effects of off-road vehicles (ORVs) on the physical and chemical properties of 6 soil series were measured at Hollister Hills State Vehicular Recreation Area in central California. Accelerated soil erosion and the alteration of surface strength, bulk density, soil moisture, temperature, and soil nutrients were quantified to gain an insight into the difficulty of revegetating altered, or modified, areas.

Robert H. Webb; H. Craig Ragland; William H. Godwin; Oennis Jenkins

1978-01-01

15

RAVON --The Robust Autonomous Vehicle for Off-road Navigation  

E-print Network

(Gantenbrink and Belless, 1999), agricultural automa- tion (Thuilot et al., 2001; Lenain et al., 2003; Debenest et al., 2003). Unmanned vehicles could patrol borders, guard industrial estates, fulfil of potentially dangerous situations. However, despite the strong need for autonomous vehicles, most

Berns, Karsten

16

Future Emissions Impact On Off-Road Vehicles  

SciTech Connect

Summaries of paper: Emission requirements dictate vehicle update cycles; Packaging, performance and cost impacted; Styling updates can be integrated; Opportunity to integrate features and performance; Non-uniform regulations challenge resources; and Customers won't expect to pay more or receive less.

Kirby Baumgard; Steve Ephraim

2001-04-18

17

Physiological fitness and health adaptations from purposeful training using off-road vehicles  

Microsoft Academic Search

The purpose of this study was to evaluate fitness and health adaptations from a training program riding all-terrain vehicles\\u000a (ATV) and off-road motorcycles (ORM) as the exercise stimulus. Participants (n = 58) were randomized to a control group (n = 12) or one of four experimental groups; 2 days\\/week ATV (n = 11), 2 days\\/week ORM (n = 12), 4 days\\/week ATV (n = 11), or 4 days\\/week ORM (n = 12). Aerobic fitness, musculoskeletal fitness,

J. F. Burr; V. K. Jamnik; N. Gledhill

18

Analysis of possibilities of waste heat recovery in off-road vehicles  

NASA Astrophysics Data System (ADS)

The paper presents the preliminary results of the waste heat recovery investigations for an agricultural tractor engine (7.4 dm3) and excavator engine (7.2 dm3) in real operating conditions. The temperature of exhaust gases and exhaust mass flow rate has been measured by precise portable exhaust emissions analyzer SEMTECH DS (SENSORS Inc.). The analysis shows that engines of tested vehicles operate approximately at constant speed and load. The average temperature of exhaust gases is in the range from 300 to 400 °C for maximum gas mass flows of 1100 kg/h and 1400 kg/h for tractor and excavator engine respectively. Preliminary tests show that application of TEGs in tested off-road vehicles offers much more beneficial conditions for waste heat recovery than in case of automotive engines.

Wojciechowski, K. T.; Zybala, R.; Leszczynski, J.; Nieroda, P.; Schmidt, M.; Merkisz, J.; Lijewski, P.; Fuc, P.

2012-06-01

19

A suite of tools for monitoring and assessing impacts of road networks and off-road vehicle activity on rangelands  

Technology Transfer Automated Retrieval System (TEKTRAN)

Despite increasing amounts of transportation related activities on rangelands globally, few tools exist for assessing and monitoring impacts of roads, road networks and off-road vehicle traffic. This is in part due to an historical emphasis on grazing issues in rangelands and the complexity of monit...

20

Shock and vibration data acquisition system for off-road vehicle operator health and safety assessment.  

PubMed

A data acquisition software and hardware system was developed for acquiring geo-referenced shock and vibration data using National Instruments' LabView graphical programming language. This was used in conjunction with a modular data acquisition and signal conditioning system and a Differential Global Positioning System (DGPS) receiver. A prototype vehicle obstacle course, which introduced spatially varying shock events to vehicles as they traversed the course, was constructed. Obstacles consisted of both repetitious and single discrete events. A series of investigations was conducted on the obstacle course to evaluate the performance and characteristics of the DAQ system and the tractor when exposed to shock and vibration events. Spectral and time domain plots obtained from the geo-referenced data acquisition system (GDAQ) system under static, highway, and off-road obstacle course conditions were evaluated to demonstrate that the system performed as expected. The migration of experiments from laboratory to field gave confidence that this system could be used to collect shock and vibration data over a wide range of frequencies. The use of geo-referenced data records proved beneficial in isolating and extracting data segments of interest from a continuous data record. PMID:17131950

Balasubramanian, K; Burks, T F; Lehtola, C J; Lee, W S

2006-11-01

21

36 CFR 13.903 - Subsistence use of off-road vehicles.  

Code of Federal Regulations, 2011 CFR

...the following designated areas and trails: (1) The Windy Creek Trail; (2) The Cantwell Airstrip Trail; (3) The Pyramid Trail; (4) The Cantwell Creek Floodplain Trail/Corridor; and (5) A trail or area along the Bull River...

2011-07-01

22

36 CFR 13.903 - Subsistence use of off-road vehicles.  

Code of Federal Regulations, 2012 CFR

...the following designated areas and trails: (1) The Windy Creek Trail; (2) The Cantwell Airstrip Trail; (3) The Pyramid Trail; (4) The Cantwell Creek Floodplain Trail/Corridor; and (5) A trail or area along the Bull River...

2012-07-01

23

36 CFR 13.903 - Subsistence use of off-road vehicles.  

Code of Federal Regulations, 2014 CFR

...the following designated areas and trails: (1) The Windy Creek Trail; (2) The Cantwell Airstrip Trail; (3) The Pyramid Trail; (4) The Cantwell Creek Floodplain Trail/Corridor; and (5) A trail or area along the Bull River...

2014-07-01

24

36 CFR 13.903 - Subsistence use of off-road vehicles.  

Code of Federal Regulations, 2013 CFR

...the following designated areas and trails: (1) The Windy Creek Trail; (2) The Cantwell Airstrip Trail; (3) The Pyramid Trail; (4) The Cantwell Creek Floodplain Trail/Corridor; and (5) A trail or area along the Bull River...

2013-07-01

25

36 CFR 13.903 - Subsistence use of off-road vehicles.  

Code of Federal Regulations, 2010 CFR

...the following designated areas and trails: (1) The Windy Creek Trail; (2) The Cantwell Airstrip Trail; (3) The Pyramid Trail; (4) The Cantwell Creek Floodplain Trail/Corridor; and (5) A trail or area along the Bull River...

2010-07-01

26

Application of an off-road mobility model to autonomous cross-country routing of unmanned ground vehicles  

NASA Astrophysics Data System (ADS)

This paper describes the application of an Army-standard legacy off-road mobility model to cross-country route planning and negotiation by unmanned ground vehicles. A planned route is created from a movement map generated from existing terrain data. An unmanned ground vehicle negotiates the planned route and makes local routing adjustments based on a trafficability assessment of terrain features which are observed from the platform. This research leverages results from other work investigating the scalability of the existing legacy off-road mobility model to small vehicles (<500 kg). The legacy mobility model is the NATO Reference Mobility Model II (NRMM II), a standard for combat mobility modeling and procurement since the mid-90's.

Cummins, Christopher L.; Jones, Randolph A.; Gates, Burhman Q., Jr.

2006-05-01

27

A cross-sectional examination of the physical fitness and selected health attributes of recreational all-terrain vehicle riders and off-road motorcyclists  

Microsoft Academic Search

The aims of this study were: (1) to characterize selected fitness and health attributes of two types of habitual recreational off-road vehicle riders – off-road motorcyclists and all-terrain vehicle riders; (2) to explore differences among riders in terms of vehicle type, age, and gender; and (3) to compare the fitness and health of riders to population norms and clinical health standards. Canadian

Jamie F. Burr; Veronica Jamnik; Norman Gledhill

2010-01-01

28

Vegetation versus man-made object detection from imagery for unmanned vehicles in off-road environments  

NASA Astrophysics Data System (ADS)

There have been several major advances in autonomous navigation for unmanned ground vehicles in controlled urban environments in recent years. However, off-road environments still pose several perception and classification challenges. This paper addresses two of these challenges: detection and classification of vegetation vs. man-made objects. In order for a vehicle or remote operator to traverse cross-country terrain, automated decisions must be made about obstacles in the vehicle's path. The most common obstacle is vegetation, but some vegetation may be traversable, depending on the size of the vehicle and the type of vegetation. However, man­ made objects should generally be detected and avoided in navigation. We present recent research towards the goal of vegetation and man-made object detection in the visible spectrum. First, we look at a state-of-the-art approach to image segmentation and image saliency using natural scene statistics. Then we apply recent work in multi-class image labeling to several images taken from a small unmanned ground vehicle (UGV). This work will attempt to highlight the recent advances and challenges that lie ahead in the ultimate goal of vegetation and man-made object detection and classification in the visual spectrum from UGV.

Harguess, Josh; Larson, Jacoby

2013-05-01

29

POSITIONING AN AUTONOMOUS OFF-ROAD VEHICLE BY USING FUSED DGPS AND INERTIAL NAVIGATION  

Microsoft Academic Search

The paper deals with positioning system for an autonomous vehicle ARSKA. Localization of the vehicle is based on fusion of internal dead reckoning navigation and periodic absolute position measurements. Fusion is done by using Kalman-filtering technique. Similar kind of approach is used in correcting the heading measurement. This is important because the position error is mostly result of the accumulated

T. Schönberg; M. Ojala; J. Suomela; A. Torpo; A. Halme

1995-01-01

30

Impacts of off-road vehicles on nitrogen cycles in biological soil crusts: Resistance in different U.S. deserts  

USGS Publications Warehouse

Biological soil crusts are an important component of desert ecosystems, as they influence soil stability and fertility. This study examined and compared the short-term vehicular impacts on lichen cover and nitrogenase activity (NA) of biological soil crusts. Experimental disturbance was applied to different types of soil in regions throughout the western U.S. (Great Basin, Colorado Plateau, Sonoran, Chihuahuan, and Mojave deserts). Results show that pre-disturbance cover of soil lichens is significantly correlated with the silt content of soils, and negatively correlated with sand and clay. While disturbance appeared to reduce NA at all sites, differences were statistically significant at only 12 of the 26 sites. Cool desert sites showed a greater decline than hot desert sites, which may indicate non-heterocystic cyanobacterial species are more susceptible to disturbance than non-heterocystic species. Sandy soils showed greater reduction of NA as sand content increased, while fine-textured soils showed a greater decline as sand content increased. At all sites, higher NA before the disturbance resulted in less impact to NA post-disturbance. These results may be useful in predicting the impacts of off-road vehicles in different regions and different soils. ?? 2002 Published by Elsevier Science Ltd.

Belnap, J.

2002-01-01

31

UC SANTA BARBARA POLICY AND PROCEDURE University Managed Vehicles Used Off-Road or In Mexico  

E-print Network

must obtain auto liability, compensation, and collision insurance. For more information about driving vehicles from commercial vendors, they must purchase supplemental liability insurance (SLI) and loss damage waiver insurance (LDW) from the vendor. C. Mexican insurance requirements must be met for all owned

Liebling, Michael

32

Fuel Used for Off-Road Recreation: A Reassessment of the Fuel Use Model  

SciTech Connect

The Intermodal Surface Transportation Efficiency Act of 1991 (ISTEA) established a National Recreational Trails Funding Program and the National Recreational Trails Trust Fund. ISTEA required that certain tax revenue generated from the sales of motor fuel used for off-road recreation be transferred from the Highway Trust Funds to the Trails Trust Fund for recreational trail and facility improvements. In order to apportion the Trails Trust Fund to individual States equitably, the Federal Highway Administration (FHWA) asked the Oak Ridge National Laboratory (ORNL) in 1993 to estimate the amount of motor fuel used for off-road recreation in the State level by different vehicle types. A modification of the methodology developed by ORNL has been used to apportion funds to the States since that time.

Davis, S.C.; Truett, L.F.; Hu, P.S.

1999-07-01

33

Off-Road Vehicle Impact on Sediment Displacement and Disruption at Assateague Island National Seashore, Maryland  

E-print Network

result of ORVs. It is important to note, however, that the authors provide no mechanism for beach and dune erosion, other than the net downslope/seaward displacement of sediment by the vehicles. The most practical mechanism would be the 3 swash.... However, the actual amount of sediment that the swash can move offshore is dependent on the beach slope and varies from beach to beach (Houser and Barrett 2010). Schlacher and Morrison (2008) examined ORV impact on two ocean-exposed beaches along North...

Labude, Brian

2012-08-15

34

Real-time adaptive off-road vehicle navigation and terrain classification  

NASA Astrophysics Data System (ADS)

We are developing a complete, self-contained autonomous navigation system for mobile robots that learns quickly, uses commodity components, and has the added benefit of emitting no radiation signature. It builds on the au­tonomous navigation technology developed by Net-Scale and New York University during the Defense Advanced Research Projects Agency (DARPA) Learning Applied to Ground Robots (LAGR) program and takes advantage of recent scientific advancements achieved during the DARPA Deep Learning program. In this paper we will present our approach and algorithms, show results from our vision system, discuss lessons learned from the past, and present our plans for further advancing vehicle autonomy.

Muller, Urs A.; Jackel, Lawrence D.; LeCun, Yann; Flepp, Beat

2013-05-01

35

75 FR 48721 - Draft Environmental Impact Statement on Nabesna Off-Road Vehicle Management Plan, Wrangell-St...  

Federal Register 2010, 2011, 2012, 2013, 2014

...DEPARTMENT OF THE INTERIOR National Park Service Draft Environmental Impact Statement...Vehicle Management Plan, Wrangell-St. Elias National Park and Preserve AGENCY: National Park Service, Interior. ACTION: Notice of...

2010-08-11

36

76 FR 52690 - Final Environmental Impact Statement on Nabesna Off-Road Vehicle Management Plan, Wrangell-St...  

Federal Register 2010, 2011, 2012, 2013, 2014

...DEPARTMENT OF INTERIOR National Park Service Final Environmental Impact Statement...Vehicle Management Plan, Wrangell-St. Elias National Park and Preserve AGENCY: National Park Service, Interior. ACTION: Notice of...

2011-08-23

37

Impact of off-road vehicles (ORVs) on ghost crabs of sandy beaches with traffic restrictions: a case study of Sodwana Bay, South Africa.  

PubMed

Off-road vehicles (ORVs) are popular in coastal recreation, although they have negative impacts on sandy shores. In South Africa, ORVs are banned from most coastal areas, while some areas are designated for restricted ORV use, providing an opportunity to assess whether ORV traffic restrictions translate into biological returns. In Sodwana Bay, the impact of ORVs on ghost crab populations was investigated. During Easter 2012, ghost crab burrows were counted on beach sections open and closed to traffic. Burrow density in the Impact section was less than a third that of the Reference section, and by the end of the study burrow size in the Impact section was half that of the Reference section. ORV traffic caused a shift in burrow distribution to the Lower beach. However, differences in burrow densities between sections were 14 times smaller than differences obtained at a time when ORV use in Sodwana Bay was not controlled. While confirming the well-established detrimental effects of ORV use on sandy beach ecosystems, results demonstrated that traffic restrictions on beaches measurably minimize impacts to the fauna, thus translating into clear-cut biological returns. PMID:24370998

Lucrezi, Serena; Saayman, Melville; van der Merwe, Peet

2014-03-01

38

Assessment of propeller and off-road vehicle scarring in seagrass beds and wind-tidal flats of the southwestern Gulf of Mexico  

USGS Publications Warehouse

We used aerial photography and GIS to establish a quantitative baseline of propeller and off-road vehicle (ORV) scarring in seagrass and wind-tidal flats of the upper Laguna Madre in the Padre Island National Seashore (Texas, USA). We also examined scar recovery through comparison of recent (2002, 2005) and historical (1967) aerial photographs of the study area. Scarring intensity was calculated using two different methods. In the first, polygons were visually drawn around groups of scars on digital images. Scarring intensity was estimated as light (20%), based on the total coverage of scars within each polygon (taking into account the length, width, and density of scars). We developed a more objective method that employed creation of vector grid cells and buffers that incorporated the localized ecological impact of scars. Results of spatial and temporal analysis revealed that the polygon approach greatly underestimated the magnitude of scarring. For example, in a single photograph, 7% of seagrass area was lightly scarred according to the polygon method; but light scarring increased to 51% according to grid analysis of the same image. Our results also indicated that propeller scars in Halodule wrightii beds appear to recover in less than three years and ORV tracks have persisted in the wind-tidal flats for at least 38 years. Our approach provides resource managers with procedures for a more objective and efficient assessment of physical disturbances to seagrass and wind-tidal flats caused by boats and ORVs. ?? 2008 by Walter de Gruyter.

Martin, S.R.; Onuf, C.P.; Dunton, K.H.

2008-01-01

39

Off-road cycling injuries. An overview.  

PubMed

Off-road bicycles, commonly called 'mountain bikes', have become increasingly popular worldwide since their introduction in the western US in the late 1970s. This popularity is partly because these vehicles can be ridden on a wide variety of terrain which is not accessible to other types of bicycle. Although early versions were rather crude, off-road bicycles today typically include high strength, lightweight frames with a wide array of available suspension and braking systems. Virtually all aspects of the technology continue to evolve, including components and protective equipment. As the popularity of off-road cycling has increased, so too has the interest and level of participation in the competitive aspects of the sport. Currently, 2 organisations--the National Off-Road Bicycle Association (NORBA) and the Union Cycliste Internationale (UCI)--sponsor the major events within the US and around the world. To date, the majority of studies have been descriptive in nature, with data collected via self-report, questionnaire formats. Only 1 prospective study has been reported thus far, which surveyed a major international competition held in the US in 1994. Injury rates calculated on the basis of injuries per ride or event in competitive venues have been reported, ranging from 0.2 to 0.39% compared with 0.30% for recreational participants. Retrospective data collected from recreational and competitive riders indicate that from 20 to 88% of those surveyed reported having sustained an injury during the previous year of participation. The majority of injuries appear to be acute, traumatic episodes involving the extremities, with contusions and abrasions being the most common. In general, the incidence of more severe injuries such as dislocations, fractures and concussions is low. Comparisons between road and off-road cycling events indicate that off-road cyclists sustain more fractures, dislocations and concussions than their road-event counterparts. Future research should incorporate epidemiological methods of data collection to determine the relationships between vehicle design, terrain and safety equipment and riding-related accidents. Further, those engaged in such research should attempt to set a standard definition for injury. PMID:7618009

Pfeiffer, R P; Kronisch, R L

1995-05-01

40

Autonomous Off-Road Driving in the DARPA Grand Challenge  

E-print Network

, orientation, and velocity) given measurements from the variety of sensors available to us. The standard learned from two years of autonomous vehicle develop- ment. Autonomous navigation in the off road environment is a challenging problem, which requires the successful integration of many different sensors

Soatto, Stefano

41

DAYTIME WATER DETECTION BY FUSING MULTIPLE CUES FOR AUTONOMOUS OFF-ROAD NAVIGATION  

Microsoft Academic Search

Detecting water hazards is a significant challenge to unmanned ground vehicle autonomous off-road navigation. This paper focuses on detecting the presence of water during the daytime using color cameras. A multi-cue approach is taken. Evidence of the presence of water is generated from color, texture, and the detection of reflections in stereo range data. A rule base for fusing water

A. L. Rankin; L. H. Matthies; A. Huertas

42

Dust emission by off-road driving: Experiments on 17 arid soil types, Nevada, USA  

Microsoft Academic Search

Field experiments were conducted in Nellis Dunes Recreational Area (Clark County, Nevada, USA) to investigate emission of dust produced by off-road driving. Experiments were carried out with three types of vehicles: 4-wheelers (quads), dirt bikes (motorcycles) and dune buggies, on 17 soil types characteristic for a desert environment. Tests were done at various driving speeds, and emissions were measured for

Dirk Goossens; Brenda Buck

2009-01-01

43

Stereo vision based terrain mapping for off-road autonomous navigation  

Microsoft Academic Search

Successful off-road autonomous navigation by an unmanned ground vehicle (UGV) requires reliable perception and representation of natural terrain. While perception algorithms are used to detect driving hazards, terrain mapping algorithms are used to represent the detected hazards in a world model a UGV can use to plan safe paths. There are two primary ways to detect driving hazards with perception

Arturo L. Rankin; Andres Huertas; Larry H. Matthies

44

Target Trailing With Safe Navigation for Maritime Autonomous Surface Vehicles  

NASA Technical Reports Server (NTRS)

This software implements a motion-planning module for a maritime autonomous surface vehicle (ASV). The module trails a given target while also avoiding static and dynamic surface hazards. When surface hazards are other moving boats, the motion planner must apply International Regulations for Avoiding Collisions at Sea (COLREGS). A key subset of these rules has been implemented in the software. In case contact with the target is lost, the software can receive and follow a "reacquisition route," provided by a complementary system, until the target is reacquired. The programmatic intention is that the trailed target is a submarine, although any mobile naval platform could serve as the target. The algorithmic approach to combining motion with a (possibly moving) goal location, while avoiding local hazards, may be applicable to robotic rovers, automated landing systems, and autonomous airships. The software operates in JPL s CARACaS (Control Architecture for Robotic Agent Command and Sensing) software architecture and relies on other modules for environmental perception data and information on the predicted detectability of the target, as well as the low-level interface to the boat controls.

Wolf, Michael; Kuwata, Yoshiaki; Zarzhitsky, Dimitri V.

2013-01-01

45

Secondary Organic Aerosol from On- and Off-Road Combustion Emissions: Scientific and Policy Perspectives  

NASA Astrophysics Data System (ADS)

Combustion emissions from on-road sources such as light duty gasoline vehicles (LDGV), medium duty diesel vehicles (MDDV) and heavy duty diesel vehicles (HDDV) as well as small off-road engines (SORE) such those used in lawn and garden equipment are a major source of fine particulate matter (PM) pollution in the ambient atmosphere. Existing regulations have restricted direct PM emissions, especially for on-road sources; however, recent studies suggest that organic PM formed from the photo-oxidation of gaseous precursor emissions—so-called secondary organic aerosol (SOA)—contributes at least as much to the overall PM burden as PM "emitted from the tailpipe." A major limitation of many of these studies is that they attempt to induce from the behavior of simple emission surrogates (e.g., vaporized whole fuel) the behavior of actual combustion emissions from real world sources. This research investigates combustion emissions directly. The primary gas- and particle-phase emissions, SOA production and SOA yields from a range of different on-road and off-road combustion sources were characterized. LDGV, MDDV and HDDV were driven on chassis dynamometers over realistic, urban driving cycles. Off-road sources, including 2- and 4-stroke lawn and garden equipment and a diesel transportation refrigeration unit were tested using engine dynamometers operated over certification cycles. For nearly all gasoline engines (LDGV and SOREs), photo-oxidizing dilute combustion emissions for 3 hours produced at least as much SOA as the directly emitted primary PM. SOA increased net PM production for LDGV by a factor of 1-10, depending on the vehicle emission standard. SOA yields were found to increase with newer vehicles, which have lower primary emissions. SOA for diesel vehicles, while still large on an absolute basis, was a smaller fraction of the primary PM emissions (between 10-30%), due to the very high elemental carbon (EC) emissions from vehicles without diesel particulate filters (DPF). Aftertreatment systems utilizing a DPF and a diesel oxidation catalyst essentially eliminated primary PM and SOA. Among the off-road sources, SOA from 2-stroke emissions increased the net PM by roughly a factor of 2. Primary emission and SOA production factors from the various combustion sources tested in this work were combined with fuel consumption data for California's South Coast Air Basin (SoCAB) to determine the impact on the aggregate PM from on- and off-road sources in the region. These estimated impacts were compared to the PM values derived from the regulatory models EMFAC and OFFROAD. Our data indicate that PM from on-road gasoline sources is significantly under-represented by existing emissions models due to the dominant role of SOA. When SOA production is included, newer LDGV are one of the largest sources of PM in SoCAB. Furthermore, LDGV will become an even more important PM source once existing regulations requiring DPF retrofits on both on- and off-road diesel sources are implemented over the next few years. While on-road diesel vehicles are currently an important source of PM based on total fuel consumption, LDGV are responsible for a larger fraction of total PM. The primary and secondary PM contribution of off-road sources also appear to be high, but the magnitude remains highly uncertain, pending further experimental data. Evidence is presented that suggests that existing models may dramatically overpredict primary PM emissions from off-road sources. Regulators are strongly urged to consider the impact of SOA on net PM production.

Gordon, Timothy D.

46

Dust emission by off-road driving: Experiments on 17 arid soil types, Nevada, USA  

NASA Astrophysics Data System (ADS)

Field experiments were conducted in Nellis Dunes Recreational Area (Clark County, Nevada, USA) to investigate emission of dust produced by off-road driving. Experiments were carried out with three types of vehicles: 4-wheelers (quads), dirt bikes (motorcycles) and dune buggies, on 17 soil types characteristic for a desert environment. Tests were done at various driving speeds, and emissions were measured for a large number of grain size fractions. This paper reports the results for two size fractions of emissions: PM10 (particles < 10 ?m) and PM60 (particles < 60 ?m). The latter was considered in this study to be sufficiently representative of the total suspendable fraction (TSP). Off-road driving was found to be a significant source of dust. However, the amounts varied greatly with the type of soil and the characteristics of the top layer. Models predicting emission of dust by off-road driving should thus consider a number of soil parameters and not just one key parameter. Vehicle type and driving speed are additional parameters that affect emission. In general, 4-wheelers produce more dust than dune buggies, and dune buggies, more than dirt bikes. Higher speeds also result in higher emissions. Dust emitted by off-road driving is less coarse than the parent sediment on the road surface. Off-road driving thus results in a progressive coarsening of the top layer. Exceptions to this are silty surfaces with no, or almost no, vegetation. For such surfaces no substantial differences were observed between the grain size distribution of road dust and emitted dust. Typical emission values for off-road driving on dry desert soils are: for sandy areas, 30-40 g km - 1 (PM10) and 150-250 g km - 1 (TSP); for silty areas, 100-200 g km - 1 (PM10) and 600-2000 g km - 1 (TSP); for drainages, 30-40 g km - 1 (PM10) and 100-400 g km - 1 (TSP); and for mixed terrain, 60-100 g km - 1 (PM10) and 300-800 g km - 1 (TSP). These values are for the types of vehicles tested in this study and do not refer to cars or trucks, which produce significantly more dust.

Goossens, Dirk; Buck, Brenda

2009-06-01

47

The Prediction of Noise Due to Jet Turbulence Convecting Past Flight Vehicle Trailing Edges  

NASA Technical Reports Server (NTRS)

High intensity acoustic radiation occurs when turbulence convects past airframe trailing edges. A mathematical model is developed to predict this acoustic radiation. The model is dependent on the local flow and turbulent statistics above the trailing edge of the flight vehicle airframe. These quantities are dependent on the jet and flight vehicle Mach numbers and jet temperature. A term in the model approximates the turbulent statistics of single-stream heated jet flows and is developed based upon measurement. The developed model is valid for a wide range of jet Mach numbers, jet temperature ratios, and flight vehicle Mach numbers. The model predicts traditional trailing edge noise if the jet is not interacting with the airframe. Predictions of mean-flow quantities and the cross-spectrum of static pressure near the airframe trailing edge are compared with measurement. Finally, predictions of acoustic intensity are compared with measurement and the model is shown to accurately capture the phenomenon.

Miller, Steven A. E.

2014-01-01

48

Detecting water hazards for autonomous off-road navigation  

NASA Astrophysics Data System (ADS)

Detecting water hazards for autonomous, off-road navigation of unmanned ground vehicles is a largely unexplored problem. In this paper, we catalog environmental variables that affect the difficulty of this problem, including day vs. night operation, whether the water reflects sky or other terrain features, the size of the water body, and other factors. We briefly survey sensors that are applicable to detecting water hazards in each of these conditions. We then present analyses and results for water detection for four specific sensor cases: (1) using color image classification to recognize sky reflections in water during the day, (2) using ladar to detect the presense of water bodies and to measure their depth, (3) using short-wave infrared (SWIR) imagery to detect water bodies, as well as snow and ice, and (4) using mid-wave infrared (MWIR) imagery to recognize water bodies at night. For color imagery, we demonstrate solid results with a classifier that runs at nearly video rate on a 433 MHz processor. For ladar, we present a detailed propagation analysis that shows the limits of water body detection and depth estimation as a function of lookahead distance, water depth, and ladar wavelength. For SWIR and MWIR, we present sample imagery from a variety of data collections that illustrate the potential of these sensors. These results demonstrate significant progress on this problem.

Matthies, Larry H.; Bellutta, Paolo; McHenry, Mike

2003-09-01

49

Attitudes and intentions of off-highway vehicle riders toward trail use: implications for forest managers  

USGS Publications Warehouse

Management of off-highway vehicles (OHV) in public forest areas requires up-to-date information about the attitudes and intentions of OHV riders toward trail use. A survey of 811 members of the New England Trail Riders Association was conducted in fall 2007; 380 questionnaires were completed and returned. Descriptive statistics and regressions were used to identify relationships between OHV rider attitudes, management preferences, and intentions toward two trail use-related behaviors (i.e., illegal use of trails by OHVs and the creation and/or use of unauthorized trails by OHV riders). Results reveal that the average responding association member has a negative attitude toward the two depreciative behaviors, intends to ride OHVs legally, and slightly prefers indirect over direct forms of management. Significant relationships between intentions and both attitudes and management preferences are identified. Policy and management implications and strategies are discussed. ?? 2011 by the Society of American Foresters.

Kuehn, D.M.; D'Luhosch, P. D.; Luzadis, V.A.; Malmsheimer, R.W.; Schuster, R.M.

2011-01-01

50

Daytime Water Detection by Fusing Multiple Cues for Autonomous Off-Road Navigation  

NASA Technical Reports Server (NTRS)

Detecting water hazards is a significant challenge to unmanned ground vehicle autonomous off-road navigation. This paper focuses on detecting the presence of water during the daytime using color cameras. A multi-cue approach is taken. Evidence of the presence of water is generated from color, texture, and the detection of reflections in stereo range data. A rule base for fusing water cues was developed by evaluating detection results from an extensive archive of data collection imagery containing water. This software has been implemented into a run-time passive perception subsystem and tested thus far under Linux on a Pentium based processor.

Rankin, A. L.; Matthies, L. H.; Huertas, A.

2004-01-01

51

Modeling and control of an off-road truck using electrorheological dampers  

NASA Astrophysics Data System (ADS)

This work deals with the mathematical modeling and control of the semi-active suspension of an MAN off-road truck with a payload of 5 tons which comprises electrorheological dampers. Thereby, a cascaded control structure with four controllers for the control of a quarter-car in the inner control loop and a superimposed control strategy for the overall vehicle is used. The main goal of the control strategy is to reduce the motion of the chassis (especially roll, pitch and vertical movement) while increasing driving stability. The capability of the overall control strategy is demonstrated by means of simulation studies and measurement results.

Holzmann, K.; Kemmetmüller, W.; Kugi, A.; Stork, M.; Rosenfeldt, H.; Schneider, S.

2009-02-01

52

NOVEL DATA ANALYSIS TECHNIQUE TO EVALUATE FIELD NOx AND CO2 CONTINUOUS EMISSION DATA, BASED ON THE EVALUATION OF: (1) AN OFF-ROAD DIESEL COMPACTOR RUNNING ON THREE FUEL TYPES AND (2) TWO COMPACTORS RUNNING ON DIESEL FUEL  

E-print Network

In spite of being few in number, off-road vehicles have a significant contribution to air pollutants such as NOx and CO2. Engine dynamometer test cycles have been developed in an effort to better characterize the emissions ...

Guerra, Sergio

2012-12-31

53

Exercise intensity during off-road cycling competitions  

Microsoft Academic Search

IMPELLIZZERI, F., A. SASSI, M. RODRIGUEZ-ALONSO, P. MOGNONI, and S. MARCORA. Exercise intensity during off-road cycling competitions. Med. Sci. Sports Exerc., Vol. 34, No. 11, pp. 1808 -1813, 2002. Purpose: This study was designed to quantify and describe the intensity profile of cross-country mountain-biking races using heart rate (HR) recorded during competitions. Methods: Nine mountain bikers participated in four cross-country

FRANCO IMPELLIZZERI; ALDO SASSI; MANUEL RODRIGUEZ-ALONSO; PIERO MOGNONI; SAMUELE MARCORA

2002-01-01

54

RAVON --The Robust Autonomous Vehicle for Off-road Navigation  

E-print Network

to navigation in highly unstructured, harsh, and danger- ous environments (see section 1.1 for examples variety of hazards, and its navigation system must be able to deal with complex, possibly dangerous exploration [Gantenbrink 99], agricultural automation [Thuilot 01, Lenain 03, Wellington 04], and evolution

Berns, Karsten

55

Quantification of structural loading during off-road cycling.  

PubMed

To provide data for fatigue life prediction and testing of structural components in off-road bicycles, the objective of the research described herein was to quantify the loads input to an off-road bicycle as a result of surface-induced loads. A fully instrumented test bicycle was equipped with dynamometers at the pedals, handlebars, and hubs to measure all in-plane structural loads acting through points of contact between the bicycle and both the rider and the ground. A portable data acquisition system carried by the standing rider allowed, for the first time, this loading information to be collected during extended off-road testing. In all, seven experienced riders rode a downhill trial test section with the test bicycle in both front-suspension and full-suspension configurations. The load histories were used quantitatively to describe the load components through the computation of means, standard deviations, amplitude probability density functions, and power spectral density functions. For the standing position, the coefficients of variation for the load components normal to the ground were greater than 1.2 for handlebar forces and 0.3 and 0.5-0.6 for the pedal and hub forces, respectively. Thus, the relative contribution of the dynamic loading was much greater than the static loading at the handlebars but less so at the pedals and hubs. As indicated by the rainflow count, high amplitude loading was developed approaching 3 and 5 times the weight of the test subjects at the front and rear wheels, respectively. The power spectral densities showed that energy was concentrated in the band 0-50 Hz. Through stress computations and knowledge of material properties, the data can be used analytically to predict the fatigue life of important structural components such as those for steering. The data can also be used to develop a fatigue testing protocol for verifying analytical predictions of fatigue life. PMID:10464694

De Lorenzo, D S; Hull, M L

1999-08-01

56

Traffic Flow of Interacting Self-Driven Particles: Rails and Trails, Vehicles and Vesicles  

NASA Astrophysics Data System (ADS)

One common feature of a vehicle, an ant and a kinesin motor is that they all convert chemical energy, derived from fuel or food, into mechanical energy required for their forward movement; such objects have been modelled in recent years as self-driven particles. Cytoskeletal filaments, e.g., microtubules, form a rail network for intra-cellular transport of vesicular cargo by molecular motors like, for example, kinesins. Similarly, ants move along trails while vehicles move along lanes. Therefore, the traffic of vehicles and organisms as well as that of molecular motors can be modelled as systems of interacting self-driven particles; these are of current interest in non-equilibrium statistical mechanics. In this paper we point out the common features of these model systems and emphasize the crucial differences in their physical properties.

Chowdhury, Debashish

57

A dynamic system model of an off-road cyclist.  

PubMed

To optimize the performance of off-road bicycle suspension systems, a dynamic model of the bicycle/rider system would be useful. This paper takes a major step toward this goal by developing a dynamic system model of the cyclist. To develop the cyclist model, a series of four vibrational tests utilizing random inputs was conducted on seven experienced off-road cyclists. This allowed the transfer functions for the arms and legs to be determined. To reproduce the essential features (i.e., resonance peaks) of the experimental transfer functions, the system model included elements representing the visceral mass along with the arms and legs. Through simulations, the frequency responses of the system model of the rider in each of the four tests were computed. Optimal stiffness and damping parameter values for each subject were determined by minimizing the difference between the experimental and simulation results. Good agreement between experimental and simulation results indicates that modeling the rider as a lumped parameter system with linear springs and dampers is possible. PMID:9285337

Wang, E L; Hull, M L

1997-08-01

58

Fuel Used for Off-Road Recreation: A Reassessment of the Fuel Use Model  

E-print Network

Fuel Used for Off-Road Recreation: A Reassessment of the Fuel Use Model Stacy C. Davis Lorena F. Truett Patricia S. Hu #12;ORNL/TM-1999/100 Fuel Used for Off-Road Recreation: A Reassessment of the Fuel.S. Department of Energy under Contract No. DE-AC05-96OR22464 #12;#12;Fuel Used for Off-Road Recreation

59

Research and Development for Off-Road Fuel Cell Applications U.S. Department of Energy Grant DE-FG36-04GO14303 - Final Report  

SciTech Connect

Off-road concerns are related to the effects of shock and vibration and air quality on fuel cell power requirements. Mechanical stresses on differing material makeup and mass distribution within the system may render some components susceptible to impulse trauma while others may show adverse effects from harmonic disturbances or broad band mechanical agitation. One of the recognized challenges in fuel cell systems air purification is in providing a highly efficient particulate and chemical filter with minimal pressure drop. PEM integrators do not want additional parasitic loads added to the system as compensation for a highly efficient yet highly restrictive filter. Additionally, there is challenge in integrating multiple functions into a single air intake module tasked with effectively filtering high dust loads, diesel soot, pesticides, ammonias, and other anticipated off-road contaminants. This project has investigated both off-road associated issues cumulating in the prototype build and testing of two light duty off-road vehicles with integrated fuel cell power plant systems.

Hicks, Michael [H2PowerTech (formerly known as IdaTech)] [H2PowerTech (formerly known as IdaTech); Erickson, Paul [Univeristy of California at Davis] [Univeristy of California at Davis; Lawrence, Richard [Retired (formerly employed by IdaTech)] [Retired (formerly employed by IdaTech); Tejaswi, Arun [Univeristy of California at Davis] [Univeristy of California at Davis; Brum, Magdalena [Univeristy of California at Davis] [Univeristy of California at Davis

2013-04-30

60

Physiological characteristics of top level off-road motorcyclists  

PubMed Central

Objectives: The study aims to analyse the physiological characteristics of top level off-road motocross, enduro, and desert rally motorcyclists to facilitate the design of a specific training program. Results: The physical demands of the various races appear to influence the development of distinct musculoskeletal characteristics, as well as aerobic and anaerobic metabolism. Motocross riders have more muscle mass, higher isokinetic handgrip strength, and greater aerobic power than enduro and desert rally riders. However, there are no significant anthropometric and physiological differences between desert rally and enduro riders. Desert rally riders tend to be overweight with maximum aerobic power similar to that of healthy individuals. The mechanical characteristics of the motorcycle and the technical and tactical skills of the riders seem to be more important for race success than the metabolic capabilities of the rider. Conclusions: Desert rally and enduro riders present similar anthropometric and physiological characteristics. Both have a maximum aerobic power similar to that of healthy normal individuals, although desert rally riders tend to be overweight. Motocross riders on the other hand, have more muscle mass, more strength, and greater aerobic power. The differences observed suggest the need for a specific training program to address the requirements of different riders to reduce the possibility of injury. PMID:16306501

Gobbi, A; Francisco, R; Tuy, B; Kvitne, R; Nakamura, N

2005-01-01

61

Mobility Erosion: High speed motion safety for mobile robots operating in off-road terrain  

E-print Network

This paper addresses the problem of ensuring mobile robot motion safety when reacting to soft and hard hazards in a static environment. The work is aimed at off-road navigation for mobile ground robots where soft hazards ...

Karumanchi, Sisir

62

A Fuel-Based Assessment of Off-Road Diesel Engine Emissions  

Microsoft Academic Search

The use of diesel engines in off-road applications is a significant source of nitrogen oxides (NOx) and particulate matter (PM10). Such off-road applications include railroad locomotives, marine vessels, and equipment used for agriculture, construction, logging, and mining. Emissions from these sources are only beginning to be controlled. Due to the large number of these engines and their wide range of

Andrew J. Kean; Robert F. Sawyer; Robert A. Harley

2000-01-01

63

Factors that Influence Tractive Performance of Wheels, Tracks, and Vehicles  

Technology Transfer Automated Retrieval System (TEKTRAN)

Traction of agricultural vehicles and other off-road vehicles is important in allowing these vehicles to perform their desired tasks. This book chapter describes factors affecting the off-road tractive performance of tires and rubber tracks. Tractive performance is affected by soil type, soil cond...

64

Night-time negative obstacle detection for off-road autonomous navigation  

NASA Astrophysics Data System (ADS)

Detecting negative obstacles (ditches, holes, wadis, and other depressions) is one of the most difficult problems in perception for unmanned ground vehicle (UGV) off-road autonomous navigation. One reason for this is that the width of the visible portion of a negative obstacle may only span a few pixels at the stopping distance for vehicle speeds UGV programs aspire to operate at (up to 50kph). The problem can be further compounded when negative obstacles are obscured by vegetation or when negative obstacles are embedded in undulating terrain. Because of the variety of appearances of negative obstacles, a multi-cue detection approach is desired. In previous nighttime negative obstacle detection work, we have described combining geometry based cues from stereo range data and a thermal signature based cue from thermal infrared imagery. Thermal signature is a powerful cue during the night since the interiors of negative obstacles generally remain warmer than surrounding terrain throughout the night. In this paper, we further couple the thermal signature based cue and geometry based cues from stereo range data for nighttime negative obstacle detection. Edge detection is used to generate closed contour candidate negative obstacle regions that are geometrically filtered to determine if they lie within the ground plane. Cues for negative obstacles from thermal signature, geometry-based analysis of range images, and geometry-based analysis of terrain maps are fused. The focus of this work is to increase the range at which UGVs can reliably detect negative obstacles on cross-country terrain, thereby increasing the speed at which UGVs can safely operate.

Rankin, Arturo L.; Huertas, Andres; Matthies, Larry H.

2007-04-01

65

Factors Affecting the Impact of Off-Road Driving on Soils in an Area in the Kruger National Park, South Africa  

NASA Astrophysics Data System (ADS)

Studies on the effects of off-road driving on soils were conducted in the Makuleke Contractual Park of the Kruger National Park. The studies were conducted on three different soils with different textures and soil compactibilities. Traffic pressure was applied with a game drive vehicle loaded with 11 sand bags, each weighing 70 kg. This gave a total vehicle mass of 3,795 kg, simulating a vehicle fully laden with tourists. The study included: (i) comparing of the effects of four different tyre pressures; (ii) comparing the effects of 1-3 vehicle passes over the same tyre tracks; (iii) comparison of traffic effects under dry and wet soil moisture conditions, on soil compaction, respectively. After each pass penetration resistances were measured (a) on the tyre tracks, (b) between the tyre tracks and (c) at different distances outside the tyre tracks. As expected, vehicular traffic caused soil compaction below the wheel tracks. Lower tyre pressures caused less compaction than higher tyre pressures. Fewer vehicle passes also caused less compaction than more passes on the same tracks, but most compaction occurred during the first pass. Thus, driving on the same tracks more than once is less damaging than driving once on different tracks. Controlled traffic should be considered when developing management strategies for off-road driving in wildlife protected areas.

Nortjé, Gerhardus Petrus; van Hoven, Wouter; Laker, Michiel C.

2012-12-01

66

Factors affecting the impact of off-road driving on soils in an area in the Kruger National Park, South Africa.  

PubMed

Studies on the effects of off-road driving on soils were conducted in the Makuleke Contractual Park of the Kruger National Park. The studies were conducted on three different soils with different textures and soil compactibilities. Traffic pressure was applied with a game drive vehicle loaded with 11 sand bags, each weighing 70 kg. This gave a total vehicle mass of 3,795 kg, simulating a vehicle fully laden with tourists. The study included: (i) comparing of the effects of four different tyre pressures; (ii) comparing the effects of 1-3 vehicle passes over the same tyre tracks; (iii) comparison of traffic effects under dry and wet soil moisture conditions, on soil compaction, respectively. After each pass penetration resistances were measured (a) on the tyre tracks, (b) between the tyre tracks and (c) at different distances outside the tyre tracks. As expected, vehicular traffic caused soil compaction below the wheel tracks. Lower tyre pressures caused less compaction than higher tyre pressures. Fewer vehicle passes also caused less compaction than more passes on the same tracks, but most compaction occurred during the first pass. Thus, driving on the same tracks more than once is less damaging than driving once on different tracks. Controlled traffic should be considered when developing management strategies for off-road driving in wildlife protected areas. PMID:23079698

Nortjé, Gerhardus Petrus; van Hoven, Wouter; Laker, Michiel C

2012-12-01

67

Stereo-vision-based terrain mapping for off-road autonomous navigation  

NASA Astrophysics Data System (ADS)

Successful off-road autonomous navigation by an unmanned ground vehicle (UGV) requires reliable perception and representation of natural terrain. While perception algorithms are used to detect driving hazards, terrain mapping algorithms are used to represent the detected hazards in a world model a UGV can use to plan safe paths. There are two primary ways to detect driving hazards with perception sensors mounted to a UGV: binary obstacle detection and traversability cost analysis. Binary obstacle detectors label terrain as either traversable or non-traversable, whereas, traversability cost analysis assigns a cost to driving over a discrete patch of terrain. In uncluttered environments where the non-obstacle terrain is equally traversable, binary obstacle detection is sufficient. However, in cluttered environments, some form of traversability cost analysis is necessary. The Jet Propulsion Laboratory (JPL) has explored both approaches using stereo vision systems. A set of binary detectors has been implemented that detect positive obstacles, negative obstacles, tree trunks, tree lines, excessive slope, low overhangs, and water bodies. A compact terrain map is built from each frame of stereo images. The mapping algorithm labels cells that contain obstacles as nogo regions, and encodes terrain elevation, terrain classification, terrain roughness, traversability cost, and a confidence value. The single frame maps are merged into a world map where temporal filtering is applied. In previous papers, we have described our perception algorithms that perform binary obstacle detection. In this paper, we summarize the terrain mapping capabilities that JPL has implemented during several UGV programs over the last decade and discuss some challenges to building terrain maps with stereo range data.

Rankin, Arturo L.; Huertas, Andres; Matthies, Larry H.

2009-05-01

68

Effects of all-terrain vehicle trails on stream channel characteristics, Ouachita National Forest, Arkansas  

E-print Network

Creek Study Watershed Gap Creek Study Waters 0 1 2 3 Nmmnem Figure 7 The Wolf Pen Gep Trail cmnptex in the Oaechita Netteent Farcer, ~ 29 Figure 8 ATV trail in the Board Camp Creek watershed 30 (Table 1) and has roughly 21. 9 mi (35. 3 km) and 6...). This ridge-and-valley topography varies from rolling hills to steep and rugged terrain. Elevations range from ouachita National Forest ~ State Line , l County Line National Forest Boundary 0 20 40 60 Kilornesets 23 400ft (121. 95 m) to over 2500 ft...

Rohrer, Deven Michelle

2001-01-01

69

A single loading direction for fatigue life prediction and testing of handlebars for off-road bicycles  

Microsoft Academic Search

Components for off-road bicycles including handlebars continue to be recalled with regularity because of problems with structural failure as a result of high cycle fatigue in the off-road environment. The objectives of this study were to 1) devise a method for determining the point on the handlebar cross section that experiences the maximum cumulative damage when the handlebar is subjected

S. P McKenna; M. R Hill; M. L Hull

2002-01-01

70

Polarization-based water hazards detection for autonomous off-road navigation  

Microsoft Academic Search

A polarization-based method for water hazards detection is presented. The concept of polarization is introduced to computer vision to detect water hazards for autonomous off-road navigation. This method is based on the physical principle that the light reflected from water surface is partial linearly polarized and the polarization phases of them are more similar than those from the scenes around.

Bin Xie; Zhiyu Xiang; Huadong Pan; Jilin Liu

2007-01-01

71

COMPARISON OF ON AND OFF ROAD DIESEL EXHAUST SOURCES ON THE SUSCEPTIBILITY TO AN INFLUENZA INFECTION.  

EPA Science Inventory

Diesel exhaust (DE), a major component of urban air pollution, and its modulatory role in human susceptibility to respiratory infections is of great concern. The purpose of this study was to evaluate the effects of on- and off-road sources of DE exposure on the severity of an ...

72

A Fuel-Based Assessment of On-Road and Off-Road Mobile Source Emission Trends  

NASA Astrophysics Data System (ADS)

Mobile sources contribute significantly to emissions of nitrogen oxides (NOx) and fine particulate matter (PM2.5) in the United States. These emissions lead to a variety of environmental concerns including adverse human health effects and climate change. In the electric power sector, sulfur dioxide (SO2) and NOx emissions from power plants are measured directly using continuous emission monitoring systems. In contrast for mobile sources, statistical models are used to estimate average emissions from a very large and diverse population of engines. Despite much effort aimed at improving them, mobile source emission inventories continue to have large associated uncertainties. Alternate methods are needed to help evaluate estimates of mobile source emissions and quantify and reduce the associated uncertainties. In this study, a fuel-based approach is used to estimate emissions from mobile sources, including on-road and off-road gasoline and diesel engines. In this approach, engine activity is measured by fuel consumed (in contrast EPA mobile source emission models are based on vehicle km of travel and total amount of engine work output for on-road and off-road engines, respectively). Fuel consumption is defined in this study based on highway fuel tax reports for on-road engines, and from surveys of fuel wholesalers who sell tax-exempt diesel fuel for use in various off-road sectors such as agriculture, construction, and mining. Over the decade-long time period (1996-2006) that is the focus of the present study, national sales of taxable gasoline and diesel fuel intended for on-road use increased by 15 and 43%, respectively. Diesel fuel use by off-road equipment increased by about 20% over the same time period. Growth in fuel consumption offset some of the reductions in pollutant emission factors that occurred during this period. This study relies on in-use measurements of mobile source emission factors, for example from roadside and tunnel studies, remote sensing, and plume capture experiments. Extensive in-use emissions data are available for NOx, especially for on-road engines. Measurements of exhaust PM2.5 emission factors are sparse in comparison. For NOx, there have been dramatic (factor of 2) decreases in emission factors for on-road gasoline engines between 1996 and 2006, due to use of improved catalytic converters on most engines. In contrast, diesel NOx emission factors decreased more gradually over the same time period. Exhaust PM2.5 emission factors appear to have decreased for most engine categories, but emission uncertainties are large for this pollutant. Pollutant emissions were estimated by combining fuel sales with emission factors expressed per unit of fuel burned. Diesel engines are the dominant mobile source of both NOx and PM2.5; the diesel contribution to NOx has increased over time as gasoline engine emissions have declined. Comparing fuel-based emission estimates with EPA’s national emission inventory led to the following conclusions: (1) total emissions of both NOx and PM2.5 estimated by two different methods were similar, (2) the distribution of source contributions to these totals differ significantly, with higher relative contributions coming from on-road diesel engines in this study compared to EPA.

Dallmann, T. R.; Harley, R. A.

2009-12-01

73

A magneto-rheological fluid shock absorber for an off-road motorcycle  

Microsoft Academic Search

This study presents theoretical and experimental investigations of a controllable, semi-active, fail-safe, magneto-rheological fluid (MRF) shock absorber for the rear suspension of an off-road motorcycle. A fail-safe MRF damper is referred to a device that retains a minimum required damping capacity in the event of a power supply or electronic system failure. A theoretical fluid mechanics-based model is developed to

Everet O. Ericksen; Faramarz Gordaninejad

2003-01-01

74

Correlations between physiological variables and performance in high level cross country off road cyclists  

Microsoft Academic Search

Objectives: To examine the relations between maximal and submaximal indices of aerobic fitness and off road cycling performance in a homogeneous group of high level mountain bikers.Methods: 12 internationally competitive mountain bikers completed the study. Maximum oxygen uptake (V?o2max), peak power output (PPO), power output (PO), and oxygen uptake (V?o2) at first (VT) and second (RCT) ventilatory thresholds were measured

F M Impellizzeri; S M Marcora; E Rampinini; P Mognoni; A Sassi

2005-01-01

75

Layout Planning Study for Off-Road Park Facilities Based on Complex System Theory  

Microsoft Academic Search

Urban off-road park facilities layout planning is an important component of the parking system planning and an integrated system engineering issue with multi-index and multi-constraint. This paper includes the study of the organizational mechanisms of parking facilities layout form and analysis of all factors that impact the public parking facilities layout. In this paper, the author established the simplified model

Xizhou Zhang; Ying Wen; Jun Liu; Dan Wan

2009-01-01

76

Primary gas- and particle-phase emissions and secondary organic aerosol production from gasoline and diesel off-road engines.  

PubMed

Dilution and smog chamber experiments were performed to characterize the primary emissions and secondary organic aerosol (SOA) formation from gasoline and diesel small off-road engines (SOREs). These engines are high emitters of primary gas- and particle-phase pollutants relative to their fuel consumption. Two- and 4-stroke gasoline SOREs emit much more (up to 3 orders of magnitude more) nonmethane organic gases (NMOGs), primary PM and organic carbon than newer on-road gasoline vehicles (per kg of fuel burned). The primary emissions from a diesel transportation refrigeration unit were similar to those of older, uncontrolled diesel engines used in on-road vehicles (e.g., premodel year 2007 heavy-duty diesel trucks). Two-strokes emitted the largest fractional (and absolute) amount of SOA precursors compared to diesel and 4-stroke gasoline SOREs; however, 35-80% of the NMOG emissions from the engines could not be speciated using traditional gas chromatography or high-performance liquid chromatography. After 3 h of photo-oxidation in a smog chamber, dilute emissions from both 2- and 4-stroke gasoline SOREs produced large amounts of semivolatile SOA. The effective SOA yield (defined as the ratio of SOA mass to estimated mass of reacted precursors) was 2-4% for 2- and 4-stroke SOREs, which is comparable to yields from dilute exhaust from older passenger cars and unburned gasoline. This suggests that much of the SOA production was due to unburned fuel and/or lubrication oil. The total PM contribution of different mobile source categories to the ambient PM burden was calculated by combining primary emission, SOA production and fuel consumption data. Relative to their fuel consumption, SOREs are disproportionately high total PM sources; however, the vastly greater fuel consumption of on-road vehicles renders them (on-road vehicles) the dominant mobile source of ambient PM in the Los Angeles area. PMID:24261886

Gordon, Timothy D; Tkacik, Daniel S; Presto, Albert A; Zhang, Mang; Jathar, Shantanu H; Nguyen, Ngoc T; Massetti, John; Truong, Tin; Cicero-Fernandez, Pablo; Maddox, Christine; Rieger, Paul; Chattopadhyay, Sulekha; Maldonado, Hector; Maricq, M Matti; Robinson, Allen L

2013-12-17

77

Target Trailing With Safe Navigation With Colregs for Maritime Autonomous Surface Vehicles  

NASA Technical Reports Server (NTRS)

Systems and methods for operating autonomous waterborne vessels in a safe manner. The systems include hardware for identifying the locations and motions of other vessels, as well as the locations of stationary objects that represent navigation hazards. By applying a computational method that uses a maritime navigation algorithm for avoiding hazards and obeying COLREGS using Velocity Obstacles to the data obtained, the autonomous vessel computes a safe and effective path to be followed in order to accomplish a desired navigational end result, while operating in a manner so as to avoid hazards and to maintain compliance with standard navigational procedures defined by international agreement. The systems and methods have been successfully demonstrated on water with radar and stereo cameras as the perception sensors, and integrated with a higher level planner for trailing a maneuvering target.

Kuwata, Yoshiaki (Inventor); Wolf, Michael T. (Inventor); Zarzhitsky, Dimitri V. (Inventor); Aghazarian, Hrand (Inventor); Huntsberger, Terrance L. (Inventor); Howard, Andrew B. (Inventor)

2014-01-01

78

Flight and Integrated Testing: Blazing the Trail for the Ares Launch Vehicles  

NASA Technical Reports Server (NTRS)

It has been 30 years since the United States last designed and built a human-rated launch vehicle. The National Aeronautics and Space Administration (NASA) has marshaled unique resources from the government and private sectors that will carry the next generation of astronauts into space safer and more efficiently than ever and send them to the Moon to develop a permanent outpost. NASA's Flight and Integrated Test Office (FITO) located at Marshall Space Flight Center and the Ares I-X Mission Management Office have primary responsibility for developing and conducting critical ground and flight tests for the Ares I and Ares V launch vehicles. These tests will draw upon Saturn and the Space Shuttle experiences, which taught the value of using sound systems engineering practices, while also applying aerospace best practices such as "test as you fly" and other lessons learned. FITO will use a variety of methods to reduce the technical, schedule, and cost risks of flying humans safely aboard a launch vehicle.

Taylor, James L.; Cockrell, Charlie; Robinson, Kimberly; Tuma, Margaret L.; Flynn, Kevin C.; Briscoe, Jeri M.

2007-01-01

79

Efficient optimisation of a vehicle suspension system, using a gradient-based approximation method, Part 1: Mathematical modelling  

Microsoft Academic Search

A methodology is proposed for the efficient determination of gradient information, when performing gradient based optimisation of an off-road vehicle’s suspension system. The methodology is applied to a computationally expensive, non-linear vehicle model, that exhibits severe numerical noise. A recreational off-road vehicle is modelled in MSC.ADAMS, and coupled to MATLAB for the execution of the optimisation. The successive approximation method,

Michael John Thoresson; P. E. Uys; Pieter Schalk Els; Johannes Arnoldus Snyman

2009-01-01

80

Winter Motor-Vehicle EMISSIONS in  

E-print Network

­18,2005,9Yellowstonesnowcoach- es (8 gasoline and 1 diesel) were each instrumented with a portable emissions monitoring systemWinter Motor-Vehicle EMISSIONS in Yellowstone National Park A ir-pollution emissions from off- road recreational vehicles have ris- en in national importance, even as emissions from these vehicles have declined

Denver, University of

81

A hub dynamometer for measurement of wheel forces in off-road bicycling.  

PubMed

A dynamometric hubset that measures the two ground contact force components acting on a bicycle wheel in the plane of the bicycle during off-road riding while either coasting or braking was designed, constructed, and evaluated. To maintain compatibility with standard mountain bike construction, the hubs use commercially available shells with modified, strain gage-equipped axles. The axle strain gages are sensitive to forces acting in the radial and tangential directions, while minimizing sensitivity to transverse forces, steering moments, and variations in the lateral location of the center of pressure. Static calibration and a subsequent accuracy check that computed differences between applied and apparent loads developed during coasting revealed root mean squared errors of 1 percent full-scale or less (full-scale load = 4500 N). The natural frequency of the rear hub with the wheel attached exceeded 350 Hz. These performance capabilities make the dynamometer useful for its intended purpose during coasting. To demonstrate this usefulness, sample ground contact forces are presented for a subject who coasted downhill over rough terrain. The dynamometric hubset can also be used to determine ground contact forces during braking providing that the brake reaction force components are known. However, compliance of the fork can lead to high cross-sensitivity and corresponding large (> 5 percent FS) measurement errors at the front wheel. PMID:10080099

De Lorenzo, D S; Hull, M L

1999-02-01

82

Effects of Sodium Phosphate Loading on Aerobic Power and Capacity in off Road Cyclists  

PubMed Central

The main aim of this paper was to evaluate the effects of short- term (6 days) phosphate loading, as well as prolonged (21 days) intake of sodium phosphate on aerobic capacity in off-road cyclists. Nineteen well-trained cyclists were randomly divided into a supplemental (S) and control group (C). Group S was supplemented for 6 days with tri-sodium phosphate, in a dose of 50 mg·kg-1 of FFM/d, while a placebo was provided for the C group. Additionally, group S was further subjected to a 3-week supplementation of 25 mg·kg-1 FFM/d, while group C received 2g of glucose. The results indicate a significant (p < 0.05) increase in VO2max, VEmax, and O2/HR, due to sodium phosphate intake over 6 days. Also a significant (p < 0.05) decrease in HRrest and HRmax occurred. The supplementation procedure caused a significant increase (p < 0.05) in Pmax and a shift of VAT towards higher loads. There were no significant changes in the concentration of 2,3-DPG, acid-base balance and lactate concentration, due to phosphate salt intake. Key points Studies on bone acute biochemical response to loading have yielded unequivocal results. There is a paucity of research on the biochemical bone response to high impact exercise. An increase in bone turnover was observed one to two days post exercise. PMID:24149601

Czuba, Milosz; Zajac, Adam; Poprzecki, Stanislaw; Cholewa, Jaroslaw; Woska, Scott

2009-01-01

83

Magneto-rheological fluid shock absorber for suspension of an off-road motorcycle: a theoretical study  

Microsoft Academic Search

This work presents a theoretical model for the damping force of a magneto-rheological fluid (MRF) shock absorber of an off-road motorcycle. The Bingham plastic model and a 3D electromagnetic finite-element analysis are employed to develop a theoretical model to estimate the damping force of a MRF shock absorber. The mode is based on the physical parameters of the device as

Everet O. Ericksen; Faramarz Gordaninejad

2000-01-01

84

Off-Road Robot Modeling with Dextrous Manipulation Kinematics Joseph Auchter and Carl Moore  

E-print Network

Variable Camber (PVC). Simulation results of a three-wheeled vehicle with PVC demonstrate that the vehicle equipped with Passive Variable Camber. The axis of rotation of each PVC joint is perpendicular to the page

Collins, Emmanuel

85

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

Code of Federal Regulations, 2011 CFR

...Designation of roads, trails, and areas. 212.51 Section 212.51 Parks, Forests...Designation of Roads, Trails, and Areas for Motor Vehicle Use § 212.51 Designation of roads, trails, and areas. (a) General. Motor...

2011-07-01

86

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

Code of Federal Regulations, 2012 CFR

...Designation of roads, trails, and areas. 212.51 Section 212.51 Parks, Forests...Designation of Roads, Trails, and Areas for Motor Vehicle Use § 212.51 Designation of roads, trails, and areas. (a) General. Motor...

2012-07-01

87

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

Code of Federal Regulations, 2010 CFR

...Designation of roads, trails, and areas. 212.51 Section 212.51 Parks, Forests...Designation of Roads, Trails, and Areas for Motor Vehicle Use § 212.51 Designation of roads, trails, and areas. (a) General. Motor...

2010-07-01

88

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

Code of Federal Regulations, 2014 CFR

...Designation of roads, trails, and areas. 212.51 Section 212.51 Parks, Forests...Designation of Roads, Trails, and Areas for Motor Vehicle Use § 212.51 Designation of roads, trails, and areas. (a) General. Motor...

2014-07-01

89

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

Code of Federal Regulations, 2013 CFR

...Designation of roads, trails, and areas. 212.51 Section 212.51 Parks, Forests...Designation of Roads, Trails, and Areas for Motor Vehicle Use § 212.51 Designation of roads, trails, and areas. (a) General. Motor...

2013-07-01

90

Magneto-rheological fluid shock absorber for suspension of an off-road motorcycle: a theoretical study  

NASA Astrophysics Data System (ADS)

This work presents a theoretical model for the damping force of a magneto-rheological fluid (MRF) shock absorber of an off-road motorcycle. The Bingham plastic model and a 3D electromagnetic finite-element analysis are employed to develop a theoretical model to estimate the damping force of a MRF shock absorber. The mode is based on the physical parameters of the device as well as the properties of the fluid, making a valuable tool in shock absorber design for a particular application. By comparing the theoretical and experimental results, it is demonstrated that the model accurately predicts the damping force.

Ericksen, Everet O.; Gordaninejad, Faramarz

2000-06-01

91

FTIR analysis of surface functionalities on particulate matter produced by off-road diesel engines operating on diesel and biofuel.  

PubMed

Fourier transform infrared spectroscopy is applied as a powerful analytic technique for the evaluation of the chemical composition of combustion aerosols emitted by off-road engines fuelled by diesel and biofuels. Particles produced by burning diesel, heated rapeseed oil (RO), RO with ethylhexylnitrate, and heated palm oil were sampled from exhausts of representative in-use diesel engines. Multicomponent composition of diesel and biofuel particles reveal the chemistry related to a variety of functional groups containing carbon, hydrogen, oxygen, sulfur, and nitrogen. The most intensive functionalities of diesel particles are saturated C-C-H and unsaturated C=C-H aliphatic groups in alkanes and alkenes, aromatic C=C and C=C-H groups in polyaromatics, as well as sulfates and nitrated ions. The distinguished features of biofuel particles were carbonyl C=O groups in carboxylic acids, ketones, aldehydes, esters, and lactones. NO2, C-N and -NH groups in nitrocompounds and amines are found to dominate biofuel particles. Group identification is confirmed by complementary measurements of organic carbon (OC), elemental carbon, and water-soluble ion species. The relationship between infrared bands of polar oxygenated and non-polar aliphatic functionalities indicates the higher extent of the surface oxidation of biofuel particles. Findings provide functional markers of organic surface structure of off-road diesel emission, allowing for a better evaluation of relation between engine, fuel, operation condition, and particle composition, thus improving the quantification of environmental impacts of alternative energy source emissions. PMID:25318418

Popovicheva, Olga B; Kireeva, Elena D; Shonija, Natalia K; Vojtisek-Lom, Michal; Schwarz, Jaroslav

2015-03-01

92

Look-ahead preview control application to the high-mobility tracked vehicle model with trailing arms  

Microsoft Academic Search

Preview control involves using forward road information acquired from preview sensors in designing a controller. Preview control,\\u000a which is composed of feedback and feed-forward input parts can lead to better performance than feedback control alone. In\\u000a this paper, application of the preview control based on the active suspension to tracked vehicles will be introduced. The\\u000a suspension unit of the tracked

Okhyun Kang; Youngjin Park; Youn-sik Park; Moonsuk Suh

2009-01-01

93

Evaluation of off-road terrain with static stereo and monoscopic displays  

NASA Technical Reports Server (NTRS)

The National Aeronautics and Space Administration is currently funding research into the design of a Mars rover vehicle. This unmanned rover will be used to explore a number of scientific and geologic sites on the Martian surface. Since the rover can not be driven from Earth in real-time, due to lengthy communication time delays, a locomotion strategy that optimizes vehicle range and minimizes potential risk must be developed. In order to assess the degree of on-board artificial intelligence (AI) required for a rover to carry out its' mission, researchers conducted an experiment to define a no AI baseline. In the experiment 24 subjects, divided into stereo and monoscopic groups, were shown video snapshots of four terrain scenes. The subjects' task was to choose a suitable path for the vehicle through each of the four scenes. Paths were scored based on distance travelled and hazard avoidance. Study results are presented with respect to: (1) risk versus range; (2) stereo versus monocular video; (3) vehicle camera height; and (4) camera field-of-view.

Yorchak, John P.; Hartley, Craig S.

1990-01-01

94

77 FR 3123 - Special Regulations, Areas of the National Park System, Cape Hatteras National Seashore-Off-Road...  

Federal Register 2010, 2011, 2012, 2013, 2014

...compliance with vehicle and equipment...incidences of vehicle strandings...items that most drivers already have in their vehicles. Accordingly...proposed rule, only vehicles registered...province where the vehicle is...

2012-01-23

95

76 FR 55840 - Cape Hatteras National Seashore Proposed Rule: Off-Road Vehicle Management-Reopening of Public...  

Federal Register 2010, 2011, 2012, 2013, 2014

...for those who may have been affected by Hurricane Irene to submit comments. DATES: Comments...proposal closed on September 6, 2011. Hurricane Irene made landfall in the area of the...east coast into New England. Because hurricane damage may have prevented some...

2011-09-09

96

Impact analysis of off-road-vehicle use on vegetation in the Grand Mere dune environment. [Lake Michigan  

NASA Technical Reports Server (NTRS)

The author has identified the following significant results. A linear regression between percent nonvegetative land and the time variable was completed for the two sample areas. Sample area no. 1 showed an average vegetation loss of 1.901% per year, while the loss for sample area no. 2 amounted to 5.889% per year. Two basic reasons for the difference were assumed to play a role: the difference in access potential and the amount of already fragmented vegetation complexes in existence during the first year of the comparative analysis - 1970. Sample area no. 2 was located closer to potential access points and was more fragmented initially.

Schultink, G. (principal investigator)

1977-01-01

97

77 FR 20843 - Record of Decision for the Nabesna Off-Road Vehicle Management Plan and Final Environmental...  

Federal Register 2010, 2011, 2012, 2013, 2014

...DEPARTMENT OF THE INTERIOR National Park Service [NPS-AKR-WRST-0112-9413...Environmental Impact Statement, Wrangell-St. Elias National Park and Preserve AGENCY: National Park Service, Interior. ACTION: Notice of...

2012-04-06

98

Aiding Off-Road Inertial Navigation with High Performance Models of Forrest Rogers-Marcovitz, Michael George, Neal Seegmiller, and Alonzo Kelly1  

E-print Network

Aiding Off-Road Inertial Navigation with High Performance Models of Wheel Slip Forrest Rogers estimate. Unfortunately, the position- denied accuracy of the inertial navigation system (INS) is governed by large systematic errors due to wheel slip. As a result, affordable terrestrial inertial navigation

Kelly, Alonzo

99

A Comparison of Bird Detection Rates Derived from On-Road versus Off-Road Point Counts in Northern Montana1  

E-print Network

A Comparison of Bird Detection Rates Derived from On-Road versus Off-Road Point Counts in Northern Breeding Bird Survey (BBS) in place, it appears likely that many of these agencies will choose, if roadside data are to be used to monitor bird populations, we need to know: (1) if the sample

Hutto, Richard

100

Trail Database  

NSDL National Science Digital Library

Something of a veteran by Internet standards, the Trail Database has been around since 1997 and, as such, now bills itself as the "world's largest hiking trail database." "Henk," the Dutch hiker responsible for this compendium, updates the site regularly and has included a wide variety of links to helpful material here. Users can search or browse the resources, which are arranged both under general topics, such as Knots or Equipment, and by country. Those planning European hikes will find the links off the front page to foot and mouth disease-related hiking restrictions useful (though we found some of these links to be broken). In all, an impressive collection of material. The site is available in Dutch or English.

101

Paper Trails  

E-print Network

PAPER TRAILS By Brian Hawkins Submitted to the graduate degree program in the Department of Visual Arts, and the Graduate Faculty of the University of Kansas in partial fulfillment of the requirements for the degree of Master of Arts... Joplin House State Historic Site in St. Louis, Missouri, and after hearing a pianist in residence play The Magnetic Rag and Euphonic Sounds, I became obsessed with mastering the jaunty rhythms and elegant melodies associated with Joplin’s music – ragtime...

Hawkins, Brian

2014-05-31

102

Analysis of unregulated emissions from an off-road diesel engine during realistic work operations  

NASA Astrophysics Data System (ADS)

Emissions from vehicle diesel engines constitute a considerable share of anthropogenic emissions of pollutants, including many non-regulated compounds such as aromatic hydrocarbons and alkenes. One way to reduce these emissions might be to use fuels with low concentrations of aromatic hydrocarbons, such as Fischer-Tropsch (F-T) diesels. Therefore this study compared Swedish Environmental Class 1 diesel (EC1) with the F-T diesel fuel Ecopar™ in terms of emissions under varied conditions (steady state, controlled transients and realistic work operations) in order to identify factors influencing emissions in actual operation. Using F-T diesel reduced emissions of aromatic hydrocarbons, but not alkenes. Emissions were equally dependent on work operation character (load, engine speed, occurrence of transients) for both fuels. There were indications that the emissions originated from unburnt fuel, rather than from combustion products.

Lindgren, Magnus; Arrhenius, Karine; Larsson, Gunnar; Bäfver, Linda; Arvidsson, Hans; Wetterberg, Christian; Hansson, Per-Anders; Rosell, Lars

2011-09-01

103

The effects of a ketogenic diet on exercise metabolism and physical performance in off-road cyclists.  

PubMed

The main objective of this research was to determine the effects of a long-term ketogenic diet, rich in polyunsaturated fatty acids, on aerobic performance and exercise metabolism in off-road cyclists. Additionally, the effects of this diet on body mass and body composition were evaluated, as well as those that occurred in the lipid and lipoprotein profiles due to the dietary intervention. The research material included eight male subjects, aged 28.3 ± 3.9 years, with at least five years of training experience that competed in off-road cycling. Each cyclist performed a continuous exercise protocol on a cycloergometer with varied intensity, after a mixed and ketogenic diet in a crossover design. The ketogenic diet stimulated favorable changes in body mass and body composition, as well as in the lipid and lipoprotein profiles. Important findings of the present study include a significant increase in the relative values of maximal oxygen uptake (VO2max) and oxygen uptake at lactate threshold (VO2 LT) after the ketogenic diet, which can be explained by reductions in body mass and fat mass and/or the greater oxygen uptake necessary to obtain the same energy yield as on a mixed diet, due to increased fat oxidation or by enhanced sympathetic activation. The max work load and the work load at lactate threshold were significantly higher after the mixed diet. The values of the respiratory exchange ratio (RER) were significantly lower at rest and during particular stages of the exercise protocol following the ketogenic diet. The heart rate (HR) and oxygen uptake were significantly higher at rest and during the first three stages of exercise after the ketogenic diet, while the reverse was true during the last stage of the exercise protocol conducted with maximal intensity. Creatine kinase (CK) and lactate dehydrogenase (LDH) activity were significantly lower at rest and during particular stages of the 105-min exercise protocol following the low carbohydrate ketogenic diet. The alterations in insulin and cortisol concentrations due to the dietary intervention confirm the concept that the glucostatic mechanism controls the hormonal and metabolic responses to exercise. PMID:24979615

Zajac, Adam; Poprzecki, Stanis?aw; Maszczyk, Adam; Czuba, Mi?osz; Michalczyk, Ma?gorzata; Zydek, Grzegorz

2014-07-01

104

The Effects of a Ketogenic Diet on Exercise Metabolism and Physical Performance in Off-Road Cyclists  

PubMed Central

The main objective of this research was to determine the effects of a long-term ketogenic diet, rich in polyunsaturated fatty acids, on aerobic performance and exercise metabolism in off-road cyclists. Additionally, the effects of this diet on body mass and body composition were evaluated, as well as those that occurred in the lipid and lipoprotein profiles due to the dietary intervention. The research material included eight male subjects, aged 28.3 ± 3.9 years, with at least five years of training experience that competed in off-road cycling. Each cyclist performed a continuous exercise protocol on a cycloergometer with varied intensity, after a mixed and ketogenic diet in a crossover design. The ketogenic diet stimulated favorable changes in body mass and body composition, as well as in the lipid and lipoprotein profiles. Important findings of the present study include a significant increase in the relative values of maximal oxygen uptake (VO2max) and oxygen uptake at lactate threshold (VO2 LT) after the ketogenic diet, which can be explained by reductions in body mass and fat mass and/or the greater oxygen uptake necessary to obtain the same energy yield as on a mixed diet, due to increased fat oxidation or by enhanced sympathetic activation. The max work load and the work load at lactate threshold were significantly higher after the mixed diet. The values of the respiratory exchange ratio (RER) were significantly lower at rest and during particular stages of the exercise protocol following the ketogenic diet. The heart rate (HR) and oxygen uptake were significantly higher at rest and during the first three stages of exercise after the ketogenic diet, while the reverse was true during the last stage of the exercise protocol conducted with maximal intensity. Creatine kinase (CK) and lactate dehydrogenase (LDH) activity were significantly lower at rest and during particular stages of the 105-min exercise protocol following the low carbohydrate ketogenic diet. The alterations in insulin and cortisol concentrations due to the dietary intervention confirm the concept that the glucostatic mechanism controls the hormonal and metabolic responses to exercise. PMID:24979615

Zajac, Adam; Poprzecki, Stanis?aw; Maszczyk, Adam; Czuba, Mi?osz; Michalczyk, Ma?gorzata; Zydek, Grzegorz

2014-01-01

105

All-terrain vehicle accidents in Maine.  

PubMed

All-terrain vehicles (ATV) are designed for off-road vocational or recreational use. Their popularity has increased steadily, but only recently has information accumulated concerning morbidity and mortality associated with the use of these vehicles. The 221 ATV accidents reported in Maine during 1985 are reviewed to more fully characterize the trauma associated with ATV accidents. These data are compared with reports from other geographical areas and recommendations made regarding ATV use. PMID:3351997

Margolis, J L

1988-03-01

106

A BIO-DIESEL BAJA VEHICLE AND STUDENT COMPETITION  

EPA Science Inventory

The SAE Mini Baja® competition is an extremely popular design competition for students in engineering programs around the world. The competition focuses on the design of an off-road vehicle for performance and cost-of-production. The objective of the proposed effort is to ...

107

Intelligent mobility for robotic vehicles in the army after next  

NASA Astrophysics Data System (ADS)

The TARDEC Intelligent Mobility program addresses several essential technologies necessary to support the army after next (AAN) concept. Ground forces in the AAN time frame will deploy robotic unmanned ground vehicles (UGVs) in high-risk missions to avoid exposing soldiers to both friendly and unfriendly fire. Prospective robotic systems will include RSTA/scout vehicles, combat engineering/mine clearing vehicles, indirect fire artillery and missile launch platforms. The AAN concept requires high on-road and off-road mobility, survivability, transportability/deployability and low logistics burden. TARDEC is developing a robotic vehicle systems integration laboratory (SIL) to evaluate technologies and their integration into future UGV systems. Example technologies include the following: in-hub electric drive, omni-directional wheel and steering configurations, off-road tires, adaptive tire inflation, articulated vehicles, active suspension, mine blast protection, detection avoidance and evasive maneuver. This paper will describe current developments in these areas relative to the TARDEC intelligent mobility program.

Gerhart, Grant R.; Goetz, Richard C.; Gorsich, David J.

1999-07-01

108

The Pimlico Chemistry Trail.  

ERIC Educational Resources Information Center

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)

Borrows, Peter

1984-01-01

109

Computational investigation of blast survivability and off-road performance of an up-armoured high-mobility  

E-print Network

of the vehicle and, secondly, the ability of the vehicle to withstand a simple straight-line brake manoeuvre contact is no longer defined as a discernible front line that can be physically identi- fied on a map at any time. This means that supply lines and logistical missions that were historically secure now

Grujicic, Mica

110

Pick A Trail  

NSDL National Science Digital Library

Developed by the Wilderness Society, the Pick a Trail Web site offers general information about backpacking and hiking in the United States and different trails in other countries, such as the United Kingdom. The trails featured on the site are organized alphabetically, with a special emphasis placed on those trails leading through the US National Park System. Information on each trail includes a brief sketch of the host country, including basic climatic information, local topography, and the type of terrain that each trail traverses. Along with this material, there are short essays on subjects related to hiking, such as identifying local plant species, associated health risks, and what items to bring along. Rounding out the site is an interactive map of the United States that allows visitors to click on each individual state to obtain an overall profile of the trails located there.

2002-01-01

111

25 CFR 170.137 - What types of activities can a recreation, tourism, and trails program include?  

Code of Federal Regulations, 2012 CFR

...activities can a recreation, tourism, and trails program include...perform under a recreation, tourism, and trails program: (1) Transportation planning for tourism and recreation travel; ...vehicle parking areas; (3) Development of tourist information...

2012-04-01

112

25 CFR 170.137 - What types of activities can a recreation, tourism, and trails program include?  

Code of Federal Regulations, 2014 CFR

...activities can a recreation, tourism, and trails program include...perform under a recreation, tourism, and trails program: (1) Transportation planning for tourism and recreation travel; ...vehicle parking areas; (3) Development of tourist information...

2014-04-01

113

25 CFR 170.137 - What types of activities can a recreation, tourism, and trails program include?  

Code of Federal Regulations, 2013 CFR

...activities can a recreation, tourism, and trails program include...perform under a recreation, tourism, and trails program: (1) Transportation planning for tourism and recreation travel; ...vehicle parking areas; (3) Development of tourist information...

2013-04-01

114

25 CFR 170.137 - What types of activities can a recreation, tourism, and trails program include?  

Code of Federal Regulations, 2011 CFR

...activities can a recreation, tourism, and trails program include...perform under a recreation, tourism, and trails program: (1) Transportation planning for tourism and recreation travel; ...vehicle parking areas; (3) Development of tourist information...

2011-04-01

115

25 CFR 170.137 - What types of activities can a recreation, tourism, and trails program include?  

Code of Federal Regulations, 2010 CFR

...activities can a recreation, tourism, and trails program include...perform under a recreation, tourism, and trails program: (1) Transportation planning for tourism and recreation travel; ...vehicle parking areas; (3) Development of tourist information...

2010-04-01

116

DAYTIME WATER DETECTION AND LOCALIZATION FOR UNMANNED GROUND VEHICLE AUTONOMOUS NAVIGATION  

Microsoft Academic Search

Detecting water hazards is a significant challenge to unmanned ground vehicle autonomous off-road navigation. This paper focuses on detecting and localizing water bodies during the daytime using a stereo pair of color cameras. A multi-cue approach is taken. Evidence of the presence of water is generated from color, texture, and the detection of terrain reflections in stereo data. A ground

A. L. Rankin; L. H. Matthies

117

Military vehicle trafficking impacts vegetation and soil bulk density at Fort Benning, Georgia  

Technology Transfer Automated Retrieval System (TEKTRAN)

Potential increases in wind erosion that might be brought about by military vehicles travelling off-road during training are of concern to the United States military. Field studies were conducted in the summer of 2012 at Fort Benning, Georgia. The objective of the experiment was to assess the traffi...

118

Military vehicle trafficking impacts on vegetation and soil bulk density at Fort Benning, Georgia  

Technology Transfer Automated Retrieval System (TEKTRAN)

Potential increases in wind erosion that might be brought about by military vehicles travelling on off-road sites during training are of concern to the Military establishment. Field studies were conducted in the summer of 2012 at Fort Benning, Georgia. The objective of the experiment was to assess t...

119

Micro-unmanned aerodynamic vehicle  

DOEpatents

A MEMS-based micro-unmanned vehicle includes at least a pair of wings having leading wing beams and trailing wing beams, at least two actuators, a leading actuator beam coupled to the leading wing beams, a trailing actuator beam coupled to the trailing wing beams, a vehicle body having a plurality of fulcrums pivotally securing the leading wing beams, the trailing wing beams, the leading actuator beam and the trailing actuator beam and having at least one anisotropically etched recess to accommodate a lever-fulcrum motion of the coupled beams, and a power source.

Reuel, Nigel (Rio Rancho, NM); Lionberger, Troy A. (Ann Arbor, MI); Galambos, Paul C. (Albuquerque, NM); Okandan, Murat (Albuquerque, NM); Baker, Michael S. (Albuquerque, NM)

2008-03-11

120

Propane Vehicle Demonstration Grant Program  

SciTech Connect

Project Description: Propane Vehicle Demonstration Grants The Propane Vehicle Demonstration Grants was established to demonstrate the benefits of new propane equipment. The US Department of Energy, the Propane Education & Research Council (PERC) and the Propane Vehicle Council (PVC) partnered in this program. The project impacted ten different states, 179 vehicles, and 15 new propane fueling facilities. Based on estimates provided, this project generated a minimum of 1,441,000 new gallons of propane sold for the vehicle market annually. Additionally, two new off-road engines were brought to the market. Projects originally funded under this project were the City of Portland, Colorado, Kansas City, Impco Technologies, Jasper Engines, Maricopa County, New Jersey State, Port of Houston, Salt Lake City Newspaper, Suburban Propane, Mutual Liquid Propane and Ted Johnson.

Jack Mallinger

2004-08-27

121

Persistent Leonid Meteor Trails  

NASA Astrophysics Data System (ADS)

In 1998 and 1999 a campaign was conducted to study the lingering trails left by (brighter than -1.5 mag) Leonid meteors over the Starfire Optical Range near Albuquerque, NM, a facility owned by the Directed Energy Directorate of the Air Force Research Laboratory. Although not unique to the Leonids, lingering trails are characteristic of the brighter members of this shower, even in non-storm years. They are self-luminous from unknown chemiluminscent reactions involving both atmospheric and cometary species. A sodium lidar was used to probe the aftermath of several meteors, some of which left trails visible for more than 20 minutes. CCD images have been analyzed for four trails. The classical explanation of the double line appearance of many trails as shell burning in an optically thin cylinder is shown to be invalid. Surface brightnesses and line emission rates have been derived and indicate that the trails are overbright compared to non-Leonids by orders of magnitude, pointing perhaps to a compositional difference between lingering trails of Leonid and non-Leonid meteors. Because the atmospheric trajectory of the parent meteor is known, the winds and parameters of a gravity wave between 90-100 km above the Earth have been deduced from a single image taken 1-2 minutes after the meteor, or from a series of images. A five degree wide video camera was used to record the evolution of several trails, and a highlight video will be shown of this fascinating and mysterious phenomenon.

Drummond, J. D.; Milster, S. P.; Grime, B. W.; Gardner, C. S.; Liu, A. Z.; Chu, X.; Kelley, M. C.; Kruschwitz, C. A.; Kane, T. J.

2000-10-01

122

Fire ant trail  

NSDL National Science Digital Library

Fire ants mark their trail with a substance from the Dufour's gland. The trail used by a group of fire ants is shown. Several examples of groups of ants following each other are shown. File size is large and a highspeed connection is recommended.

0000-00-00

123

DIRBE Comet Trails  

NASA Astrophysics Data System (ADS)

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 ?m surface brightnesses of \\lt 0.1 and \\lt 0.15 MJy sr-1, respectively, which is \\lt 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 1 additional comet and 13 additional asteroids that had not previously been recognized in the DIRBE data.

Arendt, Richard G.

2014-12-01

124

DIRBE Comet Trails  

NASA Technical Reports Server (NTRS)

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.

Arendt, Richard G.

2015-01-01

125

The Manzanita Trail  

NSDL National Science Digital Library

This guide includes directions and a list of stops for the Manzanita Trail in the San Gabriel Mountains of California. Hikers can follow the trace of the Punchbowl Fault and see a variety of features, including fault gouge, slickensides and easy-to-identify juxtapositions of quite different rock types on either side of the fault. The trail also passes through many vegetation zones, which exhibit a variety of plant communities. The guide includes a detailed trip log with mileages and photos of features that can be seen from the trail.

126

The Trails Project  

NSDL National Science Digital Library

Hosted by the Kansas City, Missouri school district with support from the US Department of Education, this Website offers innovative approaches to and materials for the teaching of Western history. The Website focuses on the Santa Fe and Oregon trails, offering a variety of interactive elements for students to work with. Included here are Virtual Reality tours of selected sites along the trails, a selection of trail diaries, examples of essays written by students about the trails, and more. The true strength of the site, though, probably lies in its support materials for teachers. The site provides well-conceived, extensive lesson plans, instruction guides, and curriculum plans, and also promises a media database in the future that will include presentations, instructional materials, and pictures. However, since there has been little activity on-site in the last few months, we suggest teachers not count on that material appearing soon.

127

Make a Nature Trail  

ERIC Educational Resources Information Center

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)

Johnson, Janice K.

1973-01-01

128

Targeting TRAIL death receptors.  

PubMed

The natural occurring tumor necrosis factor related apoptosis-inducing ligand (TRAIL) induces apoptosis following binding to the two TRAIL death receptors (DRs). Its recombinant form and monoclonal antibodies against the TRAIL DRs induce cell death in a wide variety of tumor cell lines and xenografts without causing toxicity to normal cells and are therefore potential attractive anticancer agents. These agents are currently in early clinical development. The phase 1 and 2 studies showed until now limited toxicity and tumor responses have been observed. Ongoing studies focus especially on combination of these agents with other targeted therapies or cytotoxic therapies. In this review, we summarize current knowledge on these agents and highlight their potential role in the intrinsically chemotherapy-resistant glioblastomas. In addition, we discuss the mechanisms to sensitize tumors cells to rhTRAIL by combination with the proteasome inhibitor bortezomib. PMID:18625341

Oldenhuis, C N A M; Stegehuis, J H; Walenkamp, A M E; de Jong, S; de Vries, E G E

2008-08-01

129

The Freedom Trail Foundation  

NSDL National Science Digital Library

Long before the preservation ethic and heritage tourism worlds were so closely intertwined, an enterprising journalist named William Schofield made a suggestion in the Boston Herald-Traveler to create a historical walking trail through the city that winds by some of the cityâ??s primary historical sites. Seven years later, the Freedom Trail was a reality, and it remains one of the cityâ??s most popular attractions. For the past fifty years, The Freedom Trail Foundation has been actively involved in promoting and preserving the historic character of Boston, and visitors will be delighted to know that they can learn about the Freedom Trail and the Foundation on this site. As visitors click on the â??See the 16 sitesâ? section, they will be directed to an area where they can download a walking map of the trail (which includes such landmarks as Paul Revereâ??s House and the Old North Church), and learn more about Boston during the Revolutionary Era. The site also contains a section for educators, which features lesson plans and field trip ideas for those who are intent on bringing students to the Freedom Trail. The site is rounded out by a very nice calendar of events and a selection of helpful links to other germane sites.

130

Path following of a vehicle-trailer system in presence of sliding: Application to automatic guidance of a towed agricultural implement  

Microsoft Academic Search

This paper addresses the problem of sliding parameter estimation and lateral control of an off-road vehicle-trailer system. The aim is to accurately guide the position of the trailer with respect to a planned trajectory, whatever ground conditions and trajectory shape. Relevant sliding parameter estimation is first proposed, based on the kinematic model of the system extended with side slip angles.

Christophe Cariou; Roland Lenain; Benoit Thuilot; Philippe Martinet

2010-01-01

131

Certification trails for data structures  

NASA Technical Reports Server (NTRS)

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.

Sullivan, Gregory F.; Masson, Gerald M.

1993-01-01

132

Trail user demographics, physical activity behaviors, and perceptions of a newly constructed greenway trail.  

PubMed

To better understand and promote physical activity on a newly constructed trail, the present study examined the demographic characteristics and physical activity behaviors of trail users; the demographic characteristics of trail users compared to the demographic profile Greenville County, South Carolina residents; trail users' purpose for using the trail; the distance trail users traveled to access the trail from their homes; channels through which trail users learned about the trail; and trail characteristics liked by trail users. Using a valid and reliable intercept survey, 1,148 trail users were interviewed. Trail users were mostly white (93.1%), male (59.1%) adults (84.2%) who reported using the trail for exercise (91%). Significant associations were identified between trail user demographic characteristics and how trail users learned about the trail and trail characteristics liked by trail users. The findings may contribute to the development of targeted health promotion efforts to promote physical activity on this and similar trails. PMID:22197960

Price, Anna E; Reed, Julian A; Muthukrishnan, Suresh

2012-10-01

133

Advanced Vehicle Testing and Evaluation  

SciTech Connect

The objective of the United States (U.S.) Department of Energy?s (DOEs) Advanced Vehicle Testing and Evaluation (AVTE) project was to provide test and evaluation services for advanced technology vehicles, to establish a performance baseline, to determine vehicle reliability, and to evaluate vehicle operating costs in fleet operations. Vehicles tested include light and medium-duty vehicles in conventional, hybrid, and all-electric configurations using conventional and alternative fuels, including hydrogen in internal combustion engines. Vehicles were tested on closed tracks and chassis dynamometers, as well as operated on public roads, in fleet operations, and over prescribed routes. All testing was controlled by procedures developed specifically to support such testing. Testing and evaluations were conducted in the following phases: ? Development of test procedures, which established testing procedures; ? Baseline performance testing, which established a performance baseline; ? Accelerated reliability testing, which determined vehicle reliability; ? Fleet testing, used to evaluate vehicle economics in fleet operation, and ? End of test performance evaluation. Test results are reported by two means and posted by Idaho National Laboratory (INL) to their website: quarterly progress reports, used to document work in progress; and final test reports. This final report documents work conducted for the entirety of the contract by the Clarity Group, Inc., doing business as ECOtality North America (ECOtality). The contract was performed from 1 October 2005 through 31 March 2013. There were 113 light-duty on-road (95), off-road (3) and low speed (15) vehicles tested.

Garetson, Thomas

2013-03-31

134

Trailing TRAIL Resistance: Novel Targets for TRAIL Sensitization in Cancer Cells  

PubMed Central

Resistance to chemotherapeutic drugs is the major hindrance in the successful cancer therapy. The tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a member of the tumor necrosis factor (TNF) family of ligands, which initiates apoptosis in cancer cells through interaction with the death receptors DR4 and DR5. TRAIL is perceived as an attractive chemotherapeutic agent as it specifically targets cancer cells while sparing the normal cells. However, TRAIL therapy has a major limitation as a large number of the cancer develop resistance toward TRAIL and escape from the destruction by the immune system. Therefore, elucidation of the molecular targets and signaling pathways responsible for TRAIL resistance is imperative for devising effective therapeutic strategies for TRAIL resistant cancers. Although, various molecular targets leading to TRAIL resistance are well-studied, recent studies have implicated that the contribution of some key cellular processes toward TRAIL resistance need to be fully elucidated. These processes primarily include aberrant protein synthesis, protein misfolding, ubiquitin regulated death receptor expression, metabolic pathways, epigenetic deregulation, and metastasis. Novel synthetic/natural compounds that could inhibit these defective cellular processes may restore the TRAIL sensitivity and combination therapies with such compounds may resensitize TRAIL resistant cancer cells toward TRAIL-induced apoptosis. In this review, we have summarized the key cellular processes associated with TRAIL resistance and their status as therapeutic targets for novel TRAIL-sensitizing agents.

Trivedi, Rachana; Mishra, Durga Prasad

2015-01-01

135

The Patrick Elvander Taxonomy Trail  

E-print Network

Patrick Elvander Taxonomy Trail The Patrick Elvander Taxonomy Trail at the Arboretum at UC Santa: Taxonomy is partly the study of the naming and clas- sification of plants. For this more technical to produce a preview edition of the Manual in 1989. By establishing this Taxonomy trail as a memorial, we

California at Santa Cruz, University of

136

36 CFR 331.12 - Vehicles.  

Code of Federal Regulations, 2014 CFR

...to all vehicles, including, but not limited to, automobiles, trucks, motorcycles, minibikes, trail bikes, snowmobiles, dune buggies, all terrain vehicles, bicycles, trailers, campers, or any other such equipment. (f) Except as...

2014-07-01

137

36 CFR 331.12 - Vehicles.  

Code of Federal Regulations, 2011 CFR

...to all vehicles, including, but not limited to, automobiles, trucks, motorcycles, minibikes, trail bikes, snowmobiles, dune buggies, all terrain vehicles, bicycles, trailers, campers, or any other such equipment. (f) Except as...

2011-07-01

138

36 CFR 331.12 - Vehicles.  

Code of Federal Regulations, 2013 CFR

...to all vehicles, including, but not limited to, automobiles, trucks, motorcycles, minibikes, trail bikes, snowmobiles, dune buggies, all terrain vehicles, bicycles, trailers, campers, or any other such equipment. (f) Except as...

2013-07-01

139

36 CFR 331.12 - Vehicles.  

Code of Federal Regulations, 2012 CFR

...to all vehicles, including, but not limited to, automobiles, trucks, motorcycles, minibikes, trail bikes, snowmobiles, dune buggies, all terrain vehicles, bicycles, trailers, campers, or any other such equipment. (f) Except as...

2012-07-01

140

Queen's Garden Trail  

USGS Multimedia Gallery

Views along the Queen's Garden Trail in Bryce Canyon National Park. Bryce Canyon is a unique sandstone formation in southern Utah. It is home to a large number of hoodoos, which are oddly shaped pillars of rock that formed due to different erosion rates for the dolomite that caps them and the sands...

141

Design a Hiking Trail  

NSDL National Science Digital Library

This lesson provides experience working on a real-life scenario by allowing students the opportunity to use topographic maps to design a hiking trail system based on access from road, range of habitats, and other specified criteria. They will also complete a data sheet and produce an informational brochure.

Becky Remis

142

TRAIL shows potential cardioprotective activity.  

PubMed

Recent clinical trials carried out in patients with advanced cancer have shown that recombinant TRAIL administration is usually safe and well tolerated when used either alone or in association with chemotherapeutic drugs. Notably, anticancer chemotherapy can be associated to cardiomiopathy. We have here demonstrated that TRAIL (administrated as either recombinant soluble TRAIL or as AAV-TRAIL expression viral vector) reduced the development of cardiomyopathy in the ApoE(-/-) diabetic mouse model. These data suggest, for the first time, that therapeutically administration of TRAIL might have a cardioprotective effect. PMID:21197620

Toffoli, Barbara; Bernardi, Stella; Candido, Riccardo; Zacchigna, Serena; Fabris, Bruno; Secchiero, Paola

2012-06-01

143

Experimental aerodynamics of mesoscale trailing-edge actuators  

Microsoft Academic Search

Uninhabited air vehicles (UAVs) are commonly designed with high-aspect ratio wings, which can be susceptible to significant aeroelastic vibrations. These modes can result in a loss of control or structural failure, and new techniques are necessary to alleviate them. A multidisciplinary effort at Stanford developed a distributed flow control method that used small trailing-edge actuators to alter the aerodynamic loads

Stephen Adam Solovitz

2003-01-01

144

The Hunter Skills Trail  

E-print Network

(e.g., tree stand safety, boat safe- ty, obstacle crossing, littering, etc.). Examples of scenarios begin on page 5. Materials and Equipment The items listed below are only suggestions. A successful hunter skills trail is constructed with creativity... the discus- sion. Existing stands also can be used. Check them first (just as you should before hunting) for dam- age, weak points, wasps and other animals. Camouflage: Camouflage clothing can be put on mannequins or hung on a clothes hanger in a tree...

Trail, Tamara; Hysmith, Larry; Harmel-Garza, Denise

2001-08-03

145

Cooking with Trail Mix  

E-print Network

soda ? teaspoon baking powder ? teaspoon cinnamon (if you like) ? cup trail mix What you need ? cup all-purpose flour ? teaspoon... it 1. Wash your hands; make sure your cooking area is clean. 2. Preheat the oven to 350 degrees F. 3. In a large bowl, mix sugar, applesauce, oil, egg and milk. 4. Add flour, baking soda, baking powder and cinnamon and mix it thoroughly. 5. Stir...

Anding, Jenna

2008-12-09

146

The influence of use-related, environmental, and managerial factors on soil loss from recreational trails  

USGS Publications Warehouse

Recreational uses of unsurfaced trails inevitably result in their degradation, with the type and extent of resource impact influenced by factors such as soil texture, topography, climate, trail design and maintenance, and type and amount of use. Of particular concern, the loss of soil through erosion is generally considered a significant and irreversible form of trail impact. This research investigated the influence of several use-related, environmental, and managerial factors on soil loss on recreational trails and roads at Big South Fork National River and Recreation Area, a unit of the U.S. National Park Service. Regression modeling revealed that trail position, trail slope alignment angle, grade, water drainage, and type of use are significant determinants of soil loss. The introduction of individual and groups of variables into a series of regression models provides improved understanding and insights regarding the relative influence of these variables, informing the selection of more effective trail management actions. Study results suggest that trail erosion can be minimized by avoiding ?fall-line? alignments, steep grades, and valley-bottom alignments near streams, installing and maintaining adequate densities of tread drainage features, applying gravel to harden treads, and reducing horse and all-terrain vehicle use or restricting them to more resistant routes. This research also sought to develop a more efficient Variable Cross-Sectional Area method for assessing soil loss on trails. This method permitted incorporation of CSA measures in a representative sampling scheme applied to a large (24%) sample of the park's 526 km trail system. The variety of soil loss measures derived from the Variable CSA method, including extrapolated trail-wide soil loss estimates, permit an objective quantification of soil erosion on recreational trails and roads. Such data support relational analyses to increase understanding of trail degradation, and long-term monitoring of the natural and recreational integrity of the trail system infrastructure.

Olive, N.D.; Marion, J.L.

2009-01-01

147

ProvincialParks,Trails,Beaches,andProtectedAreas Provincial Parks, Trails, Beaches,  

E-print Network

ProvincialParks,Trails,Beaches,andProtectedAreas Provincial Parks, Trails, Beaches, and Protected PARKS, TRAILS, BEACHES, AND PROTECTED AREAS TO THE STEERING PANEL February 2010 Cape Chignecto Provincial Park--Gerry Lunn #12;ProvincialParks,Trails,Beaches

Charles, Anthony

148

75 FR 32555 - Consolidated Audit Trail  

Federal Register 2010, 2011, 2012, 2013, 2014

...information gathered from these audit trail systems aids the SRO and Commission...12\\ established the Order Audit Trail System (``OATS'') \\13\\ in 1996...implemented the Consolidated Options Audit Trail System...

2010-06-08

149

77 FR 45721 - Consolidated Audit Trail  

Federal Register 2010, 2011, 2012, 2013, 2014

...maintain their own separate audit trail systems for certain segments of this...timeliness of these existing audit trail systems. Some of these shortcomings...an analysis of how existing audit trail systems do and do not meet the...

2012-08-01

150

Reduction of airfoil trailing edge noise by trailing edge blowing  

NASA Astrophysics Data System (ADS)

The paper deals with airfoil trailing edge noise and its reduction by trailing edge blowing. A Somers S834 airfoil section which originally was designed for small wind turbines is investigated. To mimic realistic Reynolds numbers the boundary layer is tripped on pressure and suction side. The chordwise position of the blowing slot is varied. The acoustic sources, i.e. the unsteady flow quantities in the turbulent boundary layer in the vicinity of the trailing edge, are quantified for the airfoil without and with trailing edge blowing by means of a large eddy simulation and complementary measurements. Eventually the far field airfoil noise is measured by a two-microphone filtering and correlation and a 40 microphone array technique. Both, LES-prediction and measurements showed that a suitable blowing jet on the airfoil suction side is able to reduce significantly the turbulence intensity and the induced surface pressure fluctuations in the trailing edge region. As a consequence, trailing edge noise associated with a spectral hump around 500 Hz could be reduced by 3 dB. For that a jet velocity of 50% of the free field velocity was sufficient. The most favourable slot position was at 90% chord length.

Gerhard, T.; Erbslöh, S.; Carolus, T.

2014-06-01

151

TRAIL-R2: a novel apoptosis-mediating receptor for TRAIL.  

PubMed Central

TRAIL is a member of the tumor necrosis factor (TNF) family of cytokines and induces apoptosis in a wide variety of cells. Based on homology searching of a private database, a receptor for TRAIL (DR4 or TRAIL-R1) was recently identified. Here we report the identification of a distinct receptor for TRAIL, TRAIL-R2, by ligand-based affinity purification and subsequent molecular cloning. TRAIL-R2 was purified independently as the only receptor for TRAIL detectable on the surface of two different human cell lines that undergo apoptosis upon stimulation with TRAIL. TRAIL-R2 contains two extracellular cysteine-rich repeats, typical for TNF receptor (TNFR) family members, and a cytoplasmic death domain. TRAIL binds to recombinant cell-surface-expressed TRAIL-R2, and TRAIL-induced apoptosis is inhibited by a TRAIL-R2-Fc fusion protein. TRAIL-R2 mRNA is widely expressed and the gene encoding TRAIL-R2 is located on human chromosome 8p22-21. Like TRAIL-R1, TRAIL-R2 engages a caspase-dependent apoptotic pathway but, in contrast to TRAIL-R1, TRAIL-R2 mediates apoptosis via the intracellular adaptor molecule FADD/MORT1. The existence of two distinct receptors for the same ligand suggests an unexpected complexity to TRAIL biology, reminiscent of dual receptors for TNF, the canonical member of this family. PMID:9311998

Walczak, H; Degli-Esposti, M A; Johnson, R S; Smolak, P J; Waugh, J Y; Boiani, N; Timour, M S; Gerhart, M J; Schooley, K A; Smith, C A; Goodwin, R G; Rauch, C T

1997-01-01

152

Base Passive Porosity for Vehicle Drag Reduction  

NASA Technical Reports Server (NTRS)

A device for controlling drag on a ground vehicle. The device consists of a porous skin or skins mounted on the trailing surface and/or aft portions of the ground vehicle. The porous skin is separated from the vehicle surface by a distance of at least the thickness of the porous skin. Alternately, the trailing surface, sides, and/or top surfaces of the ground vehicle may be porous. The device minimizes the strength of the separation in the base and wake regions of the ground vehicle, thus reducing drag.

Bauer, Steven X. S. (Inventor); Wood, Richard M. (Inventor)

2003-01-01

153

Base passive porosity for vehicle drag reduction  

NASA Technical Reports Server (NTRS)

A device for controlling drag on a ground vehicle. The device consists of a porous skin or skins mounted on the trailing surface and/or aft portions of the ground vehicle. The porous skin is separated from the vehicle surface by a distance of at least the thickness of the porous skin. Alternately, the trailing surface, sides, and/or top surfaces of the ground vehicle may be porous. The device minimizes the strength of the separation in the base and wake regions of the ground vehicle, thus reducing drag.

Bauer, Steven X. S. (Inventor); Wood, Richard M. (Inventor)

2003-01-01

154

Routing Vehicles with Ants  

NASA Astrophysics Data System (ADS)

Routing vehicles involve the design of an optimal set of routes for a fleet of vehicles to serve a number of customers with known demands. This research develops an Ant Colony Optimization for the vehicle routing with one central depot and identical vehicles. The procedure simulates the behavior of real ants that always find the shortest path between their nest and a food source through a form of communication, pheromone trail. Finally, preliminary results on the learning of the algorithm testing on benchmark data set will be presented in this paper.

Tan, Wen Fang; Lee, Lai Soon; Majid, Zanariah Abdul; Seow, Hsin Vonn

155

Trail Pheromone Disruption of Argentine Ant Trail Formation and Foraging  

USGS Publications Warehouse

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.

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

2010-01-01

156

Chemotherapy overcomes TRAIL-R4-mediated TRAIL resistance at the DISC level  

PubMed Central

TNF-related apoptosis-inducing ligand or Apo2L (Apo2L/TRAIL) is a promising anti-cancer drug owing to its ability to trigger apoptosis by binding to TRAIL-R1 or TRAIL-R2, two membrane-bound receptors that are often expressed by tumor cells. TRAIL can also bind non-functional receptors such as TRAIL-R4, but controversies still exist regarding their potential to inhibit TRAIL-induced apoptosis. We show here that TRAIL-R4, expressed either endogenously or ectopically, inhibits TRAIL-induced apoptosis. Interestingly, the combination of chemotherapeutic drugs with TRAIL restores tumor cell sensitivity to apoptosis in TRAIL-R4-expressing cells. This sensitization, which mainly occurs at the death-inducing signaling complex (DISC) level, through enhanced caspase-8 recruitment and activation, is compromised by c-FLIP expression and is independent of the mitochondria. Importantly, TRAIL-R4 expression prevents TRAIL-induced tumor regression in nude mice, but tumor regression induced by TRAIL can be restored with chemotherapy. Our results clearly support a negative regulatory function for TRAIL-R4 in controlling TRAIL signaling, and unveil the ability of TRAIL-R4 to cooperate with c-FLIP to inhibit TRAIL-induced cell death. PMID:21072058

Morizot, A; Mérino, D; Lalaoui, N; Jacquemin, G; Granci, V; Iessi, E; Lanneau, D; Bouyer, F; Solary, E; Chauffert, B; Saas, P; Garrido, C; Micheau, O

2011-01-01

157

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

Federal Register 2010, 2011, 2012, 2013, 2014

...Park Service Official Trail Marker for the Star-Spangled Banner National Historic Trail...the official trail marker insignia of the Star-Spangled Banner National Historic Trail...document is John Maounis, Superintendent, Star-Spangled Banner National Historic...

2010-06-29

158

17 CFR 37.205 - Audit trail.  

Code of Federal Regulations, 2014 CFR

...facility shall enforce its audit trail and recordkeeping...members and persons and firms subject to the swap execution...execution facility's audit trail and recordkeeping...effective enforcement of its audit trail and recordkeeping...members and persons and firms subject to the...

2014-04-01

159

Plasma instabilities in meteor trails: Linear theory  

E-print Network

Plasma instabilities in meteor trails: Linear theory Meers M. Oppenheim, Lars P. Dyrud, and Licia, such as those found at Jicamarca, Arecibo, and Kwajalein. This paper presents a theory of meteor trail electric field, the resulting electron drifts, and the linear plasma instabilities of meteor trails

Oppenheim, Meers

160

TRAIL-mediated signaling in prostate, bladder and renal cancer  

Microsoft Academic Search

Tumor necrosis factor related apoptosis inducing ligand (TRAIL) is a death receptor ligand that has the ability to preferentially initiate apoptosis in malignant cells with minimal toxicity to normal cells. TRAIL-based therapeutics, including recombinant TRAIL, TRAIL-receptor agonistic antibodies and TRAIL gene therapy, have now entered clinical trials. Although these therapeutics are promising, concerns regarding TRAIL resistance are causing research efforts

Christina Voelkel-Johnson

2011-01-01

161

Good Practice Minotaur mountain trail  

E-print Network

Good Practice Minotaur mountain trail Coed y Brenin 1. Protected Characteristic category Age to the project to make it as inclusive as possible. For example: 1 | Good practice case studies | Equality and Diversity | 14/02/2012 #12;Good Practice case studies 2 | Good practice case studies | Equality

162

'Wild Treasure' Thornless Trailing Blackberry  

Technology Transfer Automated Retrieval System (TEKTRAN)

Wild Treasure is a new trailing blackberry cultivar from the U.S. Department of Agriculture-Agricultural Research Service breeding program in Corvallis, OR, released in cooperation with Oregon State University. Wild Treasure is thornless and has high quality fruit that are very small and can be mech...

163

The Healthy Trail Food Book.  

ERIC Educational Resources Information Center

An 800-mile canoe trip down a Canadian river provided the testing ground for the tenets of this trail food book. On the seven week expedition two pounds of food per person per day at a daily cost of $1.70 were carried. The only perishables were cheese, margarine, and onions. Recipes and menu ideas from that expedition are provided along with…

Miller, Dorcas S.

164

On the Trail to Fitness.  

ERIC Educational Resources Information Center

The University of Hartford planned fitness trail will allow students to develop their bodies by providing a jogging route to improve cardiovascular fitness and exercise stations designed to provide warm-up exercises and improve strength, flexibility, balance, and endurance. (Author/MLF)

American School and University, 1979

1979-01-01

165

Bryce Canyon's Navajo Loop Trail  

USGS Multimedia Gallery

Views along the Navajo Loop Trail in Bryce Canyon National Park. Bryce Canyon is a unique sandstone formation in southern Utah. It is home to a large number of hoodoos, which are oddly shaped pillars of rock that formed due to different erosion rates for the dolomite that caps them and the sandston...

166

‘BLACK PEARL’ THORNLESS TRAILING BLACKBERRY  

Technology Transfer Automated Retrieval System (TEKTRAN)

The U.S. Department of Agriculture-Agricultural Research Service, the Oregon Agricultural Experiment Station and the Washington Agricultural Research Center have released 'Black Pearl' a thornless (botanically termed spineless) trailing blackberry for the processing market. 'Black Pearl' was selecte...

167

Trail-Directed Model Checking  

E-print Network

HSF-SPIN is a Promela model checker based on heuristic search strategies. It utilizes heuristic estimates in order to direct the search for finding software bugs in concurrent systems. As a consequence, HSF-SPIN is able to find shorter trails than blind depth-first search.

Stefan Edelkamp; Alberto Lluch-lafuente; Stefan Leue

2001-01-01

168

Ho-Nee-Um Trail.  

ERIC Educational Resources Information Center

Appreciation and concern for the preservation of our natural resources by all citizens is the primary concern of this teacher's guide for use in the elementary grades. It employes the use of a filmstrip in conjunction with a local nature trail, to guide students in developing awareness - by looking closely, listening, touching, and smelling. Major…

Irwin, Harriet; And Others

169

Natural gas vehicles : Status, barriers, and opportunities.  

SciTech Connect

In the United States, recent shale gas discoveries have generated renewed interest in using natural gas as a vehicular fuel, primarily in fleet applications, while outside the United States, natural gas vehicle use has expanded significantly in the past decade. In this report for the U.S. Department of Energy's Clean Cities Program - a public-private partnership that advances the energy, economic, and environmental security of the U.S. by supporting local decisions that reduce petroleum use in the transportation sector - we have examined the state of natural gas vehicle technology, current market status, energy and environmental benefits, implications regarding advancements in European natural gas vehicle technologies, research and development efforts, and current market barriers and opportunities for greater market penetration. The authors contend that commercial intracity trucks are a prime area for advancement of this fuel. Therefore, we examined an aggressive future market penetration of natural gas heavy-duty vehicles that could be seen as a long-term goal. Under this scenario using Energy Information Administration projections and GREET life-cycle modeling of U.S. on-road heavy-duty use, natural gas vehicles would reduce petroleum consumption by approximately 1.2 million barrels of oil per day, while another 400,000 barrels of oil per day reduction could be achieved with significant use of natural gas off-road vehicles. This scenario would reduce daily oil consumption in the United States by about 8%.

Rood Werpy, M.; Santini, D.; Burnham, A.; Mintz, M.; Energy Systems

2010-11-29

170

Experiences in teleoperation of land vehicles  

NASA Technical Reports Server (NTRS)

Teleoperation of land vehicles allows the removal of the operator from the vehicle to a remote location. This can greatly increase operator safety and comfort in applications such as security patrol or military combat. The cost includes system complexity and reduced system performance. All feedback on vehicle performance and on environmental conditions must pass through sensors, a communications channel, and displays. In particular, this requires vision to be transmitted by close-circuit television with a consequent degradation of information content. Vehicular teleoperation, as a result, places severe demands on the operator. Teleoperated land vehicles have been built and tested by many organizations, including Sandia National Laboratories (SNL). The SNL fleet presently includes eight vehicles of varying capability. These vehicles have been operated using different types of controls, displays, and visual systems. Experimentation studying the effects of vision system characteristics on off-road, remote driving was performed for conditions of fixed camera versus steering-coupled camera and of color versus black and white video display. Additionally, much experience was gained through system demonstrations and hardware development trials. The preliminary experimental findings and the results of the accumulated operational experience are discussed.

Mcgovern, Douglas E.

1989-01-01

171

Electronic Escape Trails for Firefighters  

NASA Technical Reports Server (NTRS)

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.

Jorgensen, Charles; Schipper, John; Betts, Bradley

2008-01-01

172

Growth inhibition of colorectal carcinoma by lentiviral TRAIL-transgenic human mesenchymal stem cells requires their substantial intratumoral presence  

PubMed Central

Abstract Colorectal carcinoma (CRC) constitutes a common malignancy with limited therapeutic options in metastasized stages. Mesenchymal stem cells (MSC) home to tumours and may therefore serve as a novel therapeutic tool for intratumoral delivery of antineoplastic factors. Tumour necrosis factor (TNF)-related apoptosis inducing ligand (TRAIL) which promises apoptosis induction preferentially in tumour cells represents such a factor. We generated TRAIL-MSC by transduction of human MSC with a third generation lentiviral vector system and analysed their characteristics and capacity to inhibit CRC growth. (1) TRAIL-MSC showed stable transgene expression with neither changes in the defining MSC characteristics nor signs of malignant transformation. (2) Upon direct in vitro coculture TRAIL-MSC induced apoptosis in TRAIL-sensitive CRC-cell lines (DLD-1 and HCT-15) but also in CRC-cell lines resistant to soluble TRAIL (HCT-8 and SW480). (3) In mixed subcutaneous (s.c.) xenografts TRAIL-MSC inhibited CRC-tumour growth presumably by apoptosis induction but a substantial proportion of TRAIL-MSC within the total tumour cell number was needed to yield such anti-tumour effect. (4) Systemic application of TRAIL-MSC had no effect on the growth of s.c. DLD-1 xenografts which appeared to be due to a pulmonary entrapment and low rate of tumour integration of TRAIL-MSC. Systemic TRAIL-MSC caused no toxicity in this model. (5) Wild-type MSC seemed to exert a tumour growth-supporting effect in mixed s.c. DLD-1 xenografts. These novel results support the idea that lentiviral TRAIL-transgenic human MSC may serve as vehicles for clinical tumour therapy but also highlight the need for further investigations to improve tumour integration of transgenic MSC and to clarify a potential tumour-supporting effect by MSC. PMID:19508388

Luetzkendorf, Jana; Mueller, Lutz P; Mueller, Thomas; Caysa, Henrike; Nerger, Katrin; Schmoll, Hans-Joachim

2010-01-01

173

More fatal all-terrain vehicle crashes occur on the roadway than off: increased risk-taking characterises roadway fatalities  

PubMed Central

Background All-terrain vehicles (ATVs) have steadily increased in popularity, size and speed, characteristics that likely contribute to the alarming rise in ATV-related fatalities. One potentially high-risk activity is riding on the road. Objectives To compare fatal ATV crashes that occur on the roadway and off, to more fully understand factors that contribute to fatalities at each location. Methods Fatality data from the US Consumer Product Safety Commission (CPSC) were used for descriptive and comparative analyses. Multivariate logistic regression analysis was performed to determine relative risk. Results Over 60% of all fatalities (1985–2009) resulted from roadway crashes. After 1998, roadway fatalities increased at over twice the rate of off-road fatalities. Roadway crashes were more likely than off-road crashes to involve multiple fatalities, carrying passengers, alcohol use, collisions and head injuries. Roadway victims were less likely to be helmeted than off-road victims. Passengers and operators with passengers were also less likely to be helmeted than operators riding alone. Helmeted victims were half as likely to suffer a head injury. Conclusions Fatal roadway crashes were more likely than off-road crashes to involve risk-taking behaviours (eg, carrying passengers) that could exacerbate the inherent difficulty of operating ATVs on roadway surfaces. Higher crash forces from greater speed, and lower use of protective equipment, may also have contributed to higher roadway mortality rates. Eliminating non-essential ATV road use may be an effective way to reduce ATV-related fatalities. This will likely require a substantial investment in rider education and better enforcement of ATV road use restriction laws. PMID:23257569

Denning, Gerene M; Harland, Karisa K; Ellis, David G; Jennissen, Charles A

2013-01-01

174

Evaluation of powertrain solutions for future tactical truck vehicle systems  

NASA Astrophysics Data System (ADS)

The article presents the results of a large scale design space exploration for the hybridization of two off-road vehicles, part of the Future Tactical Truck System (FTTS) family: Maneuver Sustainment Vehicle (MSV) and Utility Vehicle (UV). Series hybrid architectures are examined. The objective of the paper is to illustrate a novel design methodology that allows for the choice of the optimal values of several vehicle parameters. The methodology consists in an extensive design space exploration, which involves running a large number of computer simulations with systematically varied vehicle design parameters, where each variant is paced through several different mission profiles, and multiple attributes of performance are measured. The resulting designs are filtered to choose the design tradeoffs that better satisfy the performance and fuel economy requirements. At the end, few promising vehicle configuration designs will be selected that will need additional detailed investigation including neglected metrics like ride and drivability. Several powertrain architectures have been simulated. The design parameters include the number of axles in the vehicle (2 or 3), the number of electric motors per axle (1 or 2), the type of internal combustion engine, the type and quantity of energy storage system devices (batteries, electrochemical capacitors or both together). An energy management control strategy has also been developed to provide efficiency and performance. The control parameters are tunable and have been included into the design space exploration. The results show that the internal combustion engine and the energy storage system devices are extremely important for the vehicle performance.

Pisu, Pierluigi; Cantemir, Codrin-Gruie; Dembski, Nicholas; Rizzoni, Giorgio; Serrao, Lorenzo; Josephson, John R.; Russell, James

2006-05-01

175

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

Federal Register 2010, 2011, 2012, 2013, 2014

...other National Trail system markers. The earlier design, which...prescribed as the official trail markers for the Captain John Smith...Authorization for use of these trail markers is controlled by the administrator...OMITTED] TN29JN10.064 In making this prescription,...

2010-06-29

176

DARPA FCS unmanned ground vehicle research initiatives  

NASA Astrophysics Data System (ADS)

The Defense Advanced Research Projects Agency (DARPA) and the US Army (ASAALT) have jointly funded several FCS research initiatives in ground robotics. The Unmanned Ground Combat Vehicle (UGCV) and Perception for Off-Road Mobility (PerceptOR) programs are the major elements of this joint ground robotic effort. These programs were initiated in fiscal year 2001 and have progressed through their first phase. The UGCV program, now in Phase IB, has downselected from 11 concepts designs to 4. Phase IB focuses on detailed design of teams' concepts in anticipation of the prototype construction Phase II and initial vehicle roll-out near the end of the 2002 calendar year. This paper highlights program findings to date as a result of the initial phase, and illustrates plans for Phase II prototype testing. The PerceptOR program, currently in Phase II, has completed its Phase I which involved development of a perception system for operation on a commercial All Terrain Vehicle. This paper describes the effort of the first phase, and outlines the plans for vehicle testing in Phases II and III.

Fish, Scott

2002-07-01

177

Off-Road Motorcycling and ATV Safety  

MedlinePLUS

... to you by the American Orthopaedic Society for Sports Medicine. They provide general information only and are not ... fact sheet or learn more about other orthopaedic sports medicine topics, please visit www.sportsmed.org. Copyright © 2008. ...

178

Riding a Trail of Debris  

NASA Technical Reports Server (NTRS)

[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.

2005-01-01

179

TRAIL-R2-specific antibodies and recombinant TRAIL can synergise to kill cancer cells.  

PubMed

Tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) induces apoptosis in cancer cells while sparing normal tissues. Despite promising preclinical results, few patients responded to treatment with recombinant TRAIL (Apo2L/Dulanermin) or TRAIL-R2-specific antibodies, such as conatumumab (AMG655). It is unknown whether this was due to intrinsic TRAIL resistance within primary human cancers or insufficient agonistic activity of the TRAIL-receptor (TRAIL-R)-targeting drugs. Fc? receptors (Fc?R)-mediated crosslinking increases the cancer-cell-killing activity of TRAIL-R2-specific antibodies in vivo. We tested this phenomenon using Fc?R-expressing immune cells from patients with ovarian cancer. However, even in the presence of high numbers of Fc?R-expressing immune cells, as found in ovarian cancer ascites, AMG655-induced apoptosis was not enabled to any significant degree, indicating that this concept may not translate into clinical use. On the basis of these results, we next set out to determine whether AMG655 possibly interferes with apoptosis induction by endogenous TRAIL, which could be expressed by immune cells. To do so, we tested how AMG655 affected apoptosis induction by recombinant TRAIL. This, however, resulted in the surprising discovery of a striking synergy between AMG655 and non-tagged TRAIL (Apo2L/TRAIL) in killing cancer cells. This combination was as effective in killing cancer cells as highly active recombinant isoleucine-zipper-tagged TRAIL (iz-TRAIL). The increased killing efficiency was due to enhanced formation of the TRAIL death-inducing signalling complex, enabled by concomitant binding of Apo2L/TRAIL and AMG655 to TRAIL-R2. The synergy of AMG655 with Apo2L/TRAIL extended to primary ovarian cancer cells and was further enhanced by combination with the proteasome inhibitor bortezomib or a second mitochondrial-derived activator of caspases (SMAC) mimetic. Importantly, primary human hepatocytes were not killed by the AMG655-Apo2L/TRAIL combination, also not when further combined with bortezomib or a SMAC mimetic. We therefore propose that clinical-grade non-tagged recombinant forms of TRAIL, such as dulanermin, could be combined with antibodies such as AMG655 to introduce a highly active TRAIL-R2-agonistic therapy into the cancer clinic. PMID:24909167

Tuthill, M H; Montinaro, A; Zinngrebe, J; Prieske, K; Draber, P; Prieske, S; Newsom-Davis, T; von Karstedt, S; Graves, J; Walczak, H

2015-04-16

180

Trail inventory and assessment approaches to trail system planning at Delaware Water Gap National Recreation Area  

USGS Publications Warehouse

Trail system planning and management require accurate assessments of existing trail resources and their condition. A standardized and efficient process for surveying, inventorying, and assessing trail systems was developed and applied in the Delaware Water Gap National Recreation Area. Two approaches employed were (1) a Trail System Inventory, and (2) Prescriptive Work Logs. These complimentary approaches provide resource managers with valuable information regarding the location and length of individual trails, their current condition and needed maintenance work, and material and labor estimates necessary to conduct such work.

Williams, P.B.; Marion, J.L.

1993-01-01

181

In-Trail Procedure (ITP) Algorithm Design  

NASA Technical Reports Server (NTRS)

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.

Munoz, Cesar A.; Siminiceanu, Radu I.

2007-01-01

182

Radio propagation by reflection from meteor trails  

Microsoft Academic Search

This paper is a survey of those characteristics of meteors, and of meteor propagation, which are important to the understanding and use of meteor ionization insofar as it provides a means of radio transmission. The subjects discussed include the utility of meteor bursts for intermittent radio communication, physical properties of meteors and meteor trails, reflection properties of individual trails, short-term

G. R. Sugar

1964-01-01

183

Environment, Health & Safety Division Environmental Services Group  

E-print Network

-use, off-road diesel powered vehicles: · No vehicle or engine subject to the in-use off-road diesel-mail:ekborglin@lbl.gov February 27, 2009 NOTICE California Idling Policy for Off-road Diesel Vehicles To all operators of Lawrence Berkeley National Laboratory in-use off-road diesel vehicles: The following requirements apply to in

Eisen, Michael

184

0 50 100 150 yards White Trail (3.22 miles total)  

E-print Network

0 50 100 150 yards Scale N White Trail (3.22 miles total) White Trail (3.22 miles total) White Trail (3.22 miles total) White Trail (3.22 miles total) Blue Trail (0.4 miles) Green Trail (0.14 miles) Yellow Trail (0.7 miles) Orange Trail (1.17 miles total) Orange Trail (1.17 miles total) Orange Trail (1

Teskey, Robert O.

185

Pheromone disruption of Argentine ant trail integrity  

USGS Publications Warehouse

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.

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

2008-01-01

186

36 CFR 13.1308 - Harding Icefield Trail.  

Code of Federal Regulations, 2014 CFR

... § 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 of the trail from March 1...

2014-07-01

187

36 CFR 13.1308 - Harding Icefield Trail.  

Code of Federal Regulations, 2012 CFR

... § 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 of the trail from March 1...

2012-07-01

188

36 CFR 13.1308 - Harding Icefield Trail.  

Code of Federal Regulations, 2010 CFR

... § 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 of the trail from March 1...

2010-07-01

189

36 CFR 13.1308 - Harding Icefield Trail.  

Code of Federal Regulations, 2011 CFR

... § 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 of the trail from March 1...

2011-07-01

190

36 CFR 13.1308 - Harding Icefield Trail.  

Code of Federal Regulations, 2013 CFR

... § 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 of the trail from March 1...

2013-07-01

191

Miniature Trailing Edge Effector for Aerodynamic Control  

NASA Technical Reports Server (NTRS)

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.

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

2008-01-01

192

TrailRunner 1.8  

NSDL National Science Digital Library

Everyone's looking for an improved running or walking path, and TrailRunner can help you do just that. TrailRunner 1.8 is essentially a route planning application designed for sports like running, biking, and inline skating. Visitors can create interactive maps, review alternate routes, and export the directions onto their iPod. This version is compatible with Mac OS X 10.3.

2008-01-01

193

A standard audit trail format  

SciTech Connect

The central role of audit trails, or (more properly) logs, in security monitoring needs little description, for it is too well known for any to doubt it. Auditing, or the analysis of logs, is a central part of security not only in computer system security but also in analyzing financial and other non-technical systems. As part of this process, it is often necessary to reconcile logs from different sources. This speaks of a need for a standard logging format. A standard log format robust enough to meet the needs of heterogeneity, transportability across various network protocols, and flexibility sufficient to meet a variety of needs in very different environments must satisfy two basic properties: extensibility and portability. This report presents the author`s proposed format for a standard log record. In section 3, he shows how and where the translation should be done, and in section 4 he demonstrates how log records from several disparate systems would be put into this format. Section 5 concludes with some observations and suggestions for future work.

Bishop, M. [Univ. of California, Davis, CA (United States). Dept. of Computer Science

1995-02-01

194

Aeroelastic analysis of rotor systems using trailing edge flaps  

NASA Astrophysics Data System (ADS)

An aeroelastic analysis of rotor blades with trailing edge flaps was conducted using large deflection-type beam theory for forward flight conditions with a focus on reducing vibration while minimizing control effort. The aerodynamic forces of the rotor blade were calculated using two-dimensional quasi-steady strip theory. For the analysis of forward flight, the nonlinear periodic blade steady response was obtained by integrating the full finite element equation in time through a coupled trim procedure with a vehicle trim. The objective function, which includes vibratory hub loads and active flap control inputs, was minimized by an optimal control process. Numerical simulations were performed for the steady-state forward flight of various advance ratios. Numerical results of the steady blade and flap deflections as well as the vibratory hub loads were also presented for various advance ratios and were compared with previously published analysis results obtained from modal analyses based on a moderate deflection-type beam theory.

Lim, In-Gyu; Lee, In

2009-04-01

195

Aeroelastic Analysis of Bearingless Rotor Systems with Trailing Edge Flaps  

NASA Astrophysics Data System (ADS)

An aeroelastic analysis of bearingless rotor systems with trailing edge flaps was conducted using large deflection-type beam theory for forward flight conditions with a focus on reducing vibration while minimizing control effort. The aerodynamic forces of the rotor blade were calculated using two-dimensional quasi-steady strip theory. For the analysis of forward flight, the nonlinear periodic blade steady response was obtained by integrating the full finite element equation in time through a coupled trim procedure with a vehicle trim. The objective function, which includes vibratory hub loads and active flap control inputs, was minimized by an optimal control process. Numerical simulations were performed for the steady-state forward flight of various advance ratios. Numerical results of the steady blade and flap deflections as well as the vibratory hub loads were also presented for various advance ratios and were compared with previously published analysis results obtained from modal analyses based on a moderate deflection-type beam theory.

Lim, In-Gyu; Lee, In

196

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

ERIC Educational Resources Information Center

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…

Price, Anna E.; Reed, Julian A.

2014-01-01

197

Animal Trail Follow the clues and the map around the red trail  

E-print Network

Tan y Coed Animal Trail Clues Follow the clues and the map around the red trail keeping your eyes peeled for the animals. Machynlleth Dolgellau Bala Ffestiniog Porthmadog A A A470 A487 A470 B A487.forestry.gov.uk/cymru Canolfan Cyswllt CC Cymru: 0845 604 0845 (diwrnodiau'r wythnos yn unig) How to find us.. The Animal Puzzle

198

Interpretation of non-specular radar meteor trails  

NASA Astrophysics Data System (ADS)

Radar data of non-specular meteor trails shows two clear and consistent features: (1) non-specular meteor trails are observed from a narrower altitude range than are head echoes and (2) an approximately 20 ms delay between meteor head echoes and trail radar scatter. This paper shows that both features can result from meteor trail plasma instability. Simulations have demonstrated that trails often develop Farley-Buneman/gradient-drift (FBGD) waves which become turbulent and generate field aligned irregularities (FAI). Plasma stability analysis shows that trails are only unstable within a limited altitude range, matching the observed altitudes of non-specular trails to within 1-2 km. The simulations show that instability develops into turbulence in ~20 ms and appears to be the only meteor trail process that can explain both the observed delay between head and trail echoes and generate coherent scatter at both UHF and VHF wavelengths.

Dyrud, Lars P.; Oppenheim, Meers M.; Close, Sigrid; Hunt, Stephen

2002-11-01

199

Trailing edge modifications for flatback airfoils.  

SciTech Connect

The adoption of blunt trailing edge airfoils (also called flatback airfoils) for the inboard region of large wind turbine blades has been proposed. Blunt trailing edge airfoils would not only provide a number of structural benefits, such as increased structural volume and ease of fabrication and handling, but they have also been found to improve the lift characteristics of thick airfoils. Therefore, the incorporation of blunt trailing edge airfoils would allow blade designers to more freely address the structural demands without having to sacrifice aerodynamic performance. These airfoils do have the disadvantage of generating high levels of drag as a result of the low-pressure steady or periodic flow in the near-wake of the blunt trailing edge. Although for rotors, the drag penalty appears secondary to the lift enhancement produced by the blunt trailing edge, high drag levels are of concern in terms of the negative effect on the torque and power generated by the rotor. Hence, devices are sought that mitigate the drag of these airfoils. This report summarizes the literature on bluff body vortex shedding and bluff body drag reduction devices and proposes four devices for further study in the wind tunnel.

Kahn, Daniel L. (University of California, Davis, CA); van Dam, C.P. (University of California, Davis, CA); Berg, Dale E.

2008-03-01

200

The Trail Pheromone of the Venomous Samsum Ant, Pachycondyla sennaarensis  

PubMed Central

Ant species use branching networks of pheromone trails for orientation between nest and resources. The current study demonstrated that workers of the venomous samsum ant, Pachycondyla sennaarensis (Mayr) (Hymenoptera: Formicidae: Ponerinae), employ recruitment trail pheromones discharged from the Dufour's gland. Secretions of other abdomen complex glands, as well as hindgut gland secretions, did not evoke trail following. The optimum concentration of trail pheromone was found to be 0.1 gland equivalent/40 cm trail. This concentration demonstrated effective longevity for about one hour. This study also showed that P. sennaarensis and Tapinoma simrothi each respond to the trail pheromones of the other species as well as their own. PMID:21529253

Mashaly, Ashraf Mohamed Ali; Ahmed, Ashraf Mohamed; Al—Abdullah, Mosa Abdullah; Al—Khalifa, Mohamed Saleh

2011-01-01

201

Cuticular lipids as trail pheromone in a social wasp.  

PubMed Central

We investigated the origin and composition of the chemical trail of the common yellow jacket Vespula vulgaris L. (Vespidae) and found that an artificial trail made from an extract of cuticular lipids from V. vulgaris foragers was biologically as active as a trail laid naturally by the foragers. Chemical analysis of natural trail extracts and the behaviourally active cuticular extracts by coupled gas chromatography-mass spectrometry revealed that the majority of cuticular hydrocarbons were also present in the trail extract at similar ratios. Thus, bioassay data and chemical analysis provide strong evidence that these cuticular hydrocarbons act as a trail pheromone in V. vulgaris. PMID:12639318

Steinmetz, Inge; Schmolz, Erik; Ruther, Joachim

2003-01-01

202

Science Nation: Hydrogen Trail Blazers  

NSDL National Science Digital Library

In just the last few years, Columbia, South Carolina has transformed itself into a hotbed of hydrogen research--thanks in large part to the Industry/University Cooperative Research Center for Fuel Cells at the University of South Carolina, funded by the National Science Foundation (NSF). Hydrogen is widely hailed as the fuel of the future--plentiful and non-polluting, discharging only water vapor into the environment. Perfecting the fuel cell, which converts hydrogen into a steady stream of electricity, will be one of the keys to making hydrogen vehicles commonplace. To support the push to hydrogen, the city of Columbia, the university, and local business and industry are coordinating to put these new hydrogen technologies to work around town. One example, city policeman patrol the downtown area on hydrogen hybrid Segways.

203

11. Roaring Fork Motor Nature Trail, boulders along road after ...  

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

11. Roaring Fork Motor Nature Trail, boulders along road after stop 13. - Great Smoky Mountains National Park Roads & Bridges, Roaring Fork Motor Nature Trail, Between Cherokee Orchard Road & U.S. Route 321, Gatlinburg, Sevier County, TN

204

3. Roaring Fork Motor Nature Trail, view between second and ...  

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

3. Roaring Fork Motor Nature Trail, view between second and third stops - Great Smoky Mountains National Park Roads & Bridges, Roaring Fork Motor Nature Trail, Between Cherokee Orchard Road & U.S. Route 321, Gatlinburg, Sevier County, TN

205

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

206

12. Roaring Fork Motor Nature Trail, place of a thousand ...  

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

12. Roaring Fork Motor Nature Trail, place of a thousand drips, view from road. - Great Smoky Mountains National Park Roads & Bridges, Roaring Fork Motor Nature Trail, Between Cherokee Orchard Road & U.S. Route 321, Gatlinburg, Sevier County, TN

207

6. Roaring Fork Motor Nature Trail, road view after stop ...  

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

6. Roaring Fork Motor Nature Trail, road view after stop four. - Great Smoky Mountains National Park Roads & Bridges, Roaring Fork Motor Nature Trail, Between Cherokee Orchard Road & U.S. Route 321, Gatlinburg, Sevier County, TN

208

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

209

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

210

2. Roaring Fork Motor Nature Trail, road view before first ...  

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

2. Roaring Fork Motor Nature Trail, road view before first stop. - Great Smoky Mountains National Park Roads & Bridges, Roaring Fork Motor Nature Trail, Between Cherokee Orchard Road & U.S. Route 321, Gatlinburg, Sevier County, TN

211

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

212

7. Roaring Fork Motor Nature Trail, rocks along edge of ...  

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

7. Roaring Fork Motor Nature Trail, rocks along edge of road. - Great Smoky Mountains National Park Roads & Bridges, Roaring Fork Motor Nature Trail, Between Cherokee Orchard Road & U.S. Route 321, Gatlinburg, Sevier County, TN

213

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

214

30 CFR 56.12039 - Protection of surplus trailing cables.  

Code of Federal Regulations, 2011 CFR

...DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56.12039 Protection of surplus trailing cables. Surplus trailing cables to shovels, cranes and similar...

2011-07-01

215

30 CFR 56.12038 - Attachment of trailing cables.  

Code of Federal Regulations, 2011 CFR

...DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56.12038 Attachment of trailing cables. Trailing cables shall be attached to machines in a suitable manner to...

2011-07-01

216

30 CFR 56.12038 - Attachment of trailing cables.  

Code of Federal Regulations, 2014 CFR

...DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56.12038 Attachment of trailing cables. Trailing cables shall be attached to machines in a suitable manner to...

2014-07-01

217

30 CFR 57.12039 - Protection of surplus trailing cables.  

Code of Federal Regulations, 2013 CFR

...LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Electricity Surface and Underground § 57.12039 Protection of surplus trailing cables. Surplus trailing cables to...

2013-07-01

218

30 CFR 57.12039 - Protection of surplus trailing cables.  

Code of Federal Regulations, 2010 CFR

...LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Electricity Surface and Underground § 57.12039 Protection of surplus trailing cables. Surplus trailing cables to...

2010-07-01

219

30 CFR 57.12039 - Protection of surplus trailing cables.  

Code of Federal Regulations, 2011 CFR

...LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Electricity Surface and Underground § 57.12039 Protection of surplus trailing cables. Surplus trailing cables to...

2011-07-01

220

30 CFR 56.12039 - Protection of surplus trailing cables.  

Code of Federal Regulations, 2014 CFR

...DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56.12039 Protection of surplus trailing cables. Surplus trailing cables to shovels, cranes and similar...

2014-07-01

221

30 CFR 57.12038 - Attachment of trailing cables.  

Code of Federal Regulations, 2012 CFR

...LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Electricity Surface and Underground § 57.12038 Attachment of trailing cables. Trailing cables shall be attached to...

2012-07-01

222

Trailing Edge Noise Model Applied to Wind Turbine Airfoils  

E-print Network

Trailing Edge Noise Model Applied to Wind Turbine Airfoils Franck Bertagnolio Risø-R-1633(EN) Risø Bertagnolio Title: Trailing Edge Noise Model Applied to Wind Turbine Airfoils Department: Wind Energy generation that are relevant to wind turbine technology with focus on trailing edge noise. Secondly, the so

223

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

ERIC Educational Resources Information Center

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…

Fischer, Jim

1993-01-01

224

Machine performance and site disturbance in skidding on designated trails  

Microsoft Academic Search

Overstorey trees (predominantly western red cedar Thuja plicata) in a stand in Idaho were removed in 1981 using 4 machines and 2 methods: skidding whole trees on undesignated trails; and skidding tree lengths on trails designated in advance. A caterpillar 518 rubber-tyred skidder (RTS) handling whole trees on undesignated trails had the lowest cost and the highest production. An FMC

E. D. Olsen; J. C. W. Seifert

1984-01-01

225

17 CFR 38.553 - Enforcement of audit trail requirements.  

Code of Federal Regulations, 2014 CFR

...market must enforce its audit trail and recordkeeping...members and persons and firms subject to designated...the contract market's audit trail and recordkeeping...effective enforcement of its audit trail and recordkeeping...members and persons and firms subject to...

2014-04-01

226

17 CFR 38.553 - Enforcement of audit trail requirements.  

Code of Federal Regulations, 2013 CFR

...market must enforce its audit trail and recordkeeping...members and persons and firms subject to designated...the contract market's audit trail and recordkeeping...effective enforcement of its audit trail and recordkeeping...members and persons and firms subject to...

2013-04-01

227

An Aerial-Photographic Assessment of Reenacted Handcart Treks on a Section of the Mormon Pioneer National Historic Trail, Fremont County, Wyoming  

USGS Publications Warehouse

Reenactments of historical pioneer emigrations have increased in popularity since the celebration of these events during the United States bicentennial in 1976. From 1999 to 2006, approximately 70,000 Mormon trekkers traveled the Mormon Pioneer National Historic Trail (hereinafter referred to as the Trail) segment between Sixth Crossing and Rock Creek Hollow in Fremont County, Wyoming. Recent elevated levels of use have raised concerns over potential recreation-related damage to this particularly scenic segment of the Trail. In 2006, the Bureau of Land Management (BLM) contracted the U.S. Geological Survey (USGS) to conduct an aerial-photographic assessment of the condition of the Trail between Sixth Crossing and Rock Creek Hollow. Specifically, the USGS was to assess trail conditions for this segment as influenced by handcart use (low, medium, and high intensity of use) and concentrated activities associated with trekking (toilet, rest, and camp sites). Based on these results, there are identifiable management considerations. Toilet and rest sites need to be carefully located relative to where sensitive vegetation or soils occur. The analyses presented here indicate that limiting motorized vehicle use needs to be a priority over that of adjusting the number of trekkers. Additionally, monitoring of the Trail from Sixth Crossing to Rock Creek Hollow segment needs to consider explicit management targets, such as minimum acceptable levels of bare ground or trail width, and the establishment of permanent monitoring plots to evaluate targets and measure responses to altered management activities.

McDougal, Robert R.; Waltermire, Robert G.; Aldridge, Cameron L.; Germaine, Stephen S.; Nielsen, Scott E.; Nielsen, Charlene C.; Hanson, Leanne; Bowen, Zachary H.

2008-01-01

228

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

Federal Register 2010, 2011, 2012, 2013, 2014

...Superintendent, Ala Kahakai National Historic Trail, National Park Service, 73-4786 Kanalani Street, Suite 14, Kailua-Kona, HI 96740, 808-326- 6012. Dated: February 5, 2010. Aric P. Arakaki, Superintendent, Ala Kahakai National...

2010-03-15

229

Trails and Greenways: Alternatives to "Carmageddon."  

ERIC Educational Resources Information Center

Discusses personal and societal effects of automobile-centered landscapes and development. Recommends fundamental reexamination of community development and beliefs regarding desirable human settlement. Suggests greenways and trails as a multifunctional means for revitalizing communities in a more ecological fashion. Presents the Niagara region of…

Brown, David T.

1995-01-01

230

Enjoy the trails through the tall  

E-print Network

people to enjoy. Workers of the wood unite! Keep your eyes open for the huge ant hills among the trees. Wood ants are tireless. This woodland will enchant you with its hidden gems and variety of trails. You,peacefulpaths, dogs'delight 6.CambusO'May 'DPVHOLHV,GUDJRQLHV EXWWHULHVWLPHVWDQGVVWLOO 7.Scolty Woodlandways

231

Sandstone Formation on the Navajo Loop Trail  

USGS Multimedia Gallery

Views along the Navajo Loop Trail in Bryce Canyon National Park. Bryce Canyon is a unique sandstone formation in southern Utah. It is home to a large number of hoodoos, which are oddly shaped pillars of rock that formed due to different erosion rates for the dolomite that caps them and the sandston...

232

Snow on the Navajo Loop Trail  

USGS Multimedia Gallery

Views along the Navajo Loop Trail in Bryce Canyon National Park. Bryce Canyon is a unique sandstone formation in southern Utah. It is home to a large number of hoodoos, which are oddly shaped pillars of rock that formed due to different erosion rates for the dolomite that caps them and the sandston...

233

Hoodoo on the Navajo Loop Trail  

USGS Multimedia Gallery

Views along the Navajo Loop Trail in Bryce Canyon National Park. Bryce Canyon is a unique sandstone formation in southern Utah. It is home to a large number of hoodoos, which are oddly shaped pillars of rock that formed due to different erosion rates for the dolomite that caps them and the sandston...

234

Cedars on the Navajo Loop Trail  

USGS Multimedia Gallery

Views along the Navajo Loop Trail in Bryce Canyon National Park. Bryce Canyon is a unique sandstone formation in southern Utah. It is home to a large number of hoodoos, which are oddly shaped pillars of rock that formed due to different erosion rates for the dolomite that caps them and the sandston...

235

Flexible Audit Trailing in Interactive Courseware.  

ERIC Educational Resources Information Center

This paper reports on the development and implementation of a flexible audit trail system comprising a library of auditing functions that can be embedded into interactive courseware and customized to the requirements of researchers and developers. A series of essential criteria considered critical to the development of a robust, flexible audit…

Judd, Terry; Kennedy, Gregor

236

The OBIS Trail Module. Trial Version.  

ERIC Educational Resources Information Center

Designed to allow youngsters aged 10 to 15 to experience the challenges and problems environmental investigators might face making an environmental impact study, the trial version of the Outdoor Biology Instructional Strategies (OBIS) Trail Module focuses on aspects of construction-related environment problems. Four activities are included in the…

Fairwell, Kay, Ed.; And Others

237

Interpreter's Guide to Blackbird Marsh Nature Trail.  

ERIC Educational Resources Information Center

This booklet was prepared to help the user interpret the natural history of Blackbird Marsh Nature Trail in Escambia County, Florida, and serves as a guide to the animal and plant life. The publication is part of a series of illustrated guides designed for use by teachers and students of all levels in conjunction with field trips to the 1200-acre…

Environmental Studies Center, Pensacola, FL.

238

Gorp, Again? Alternate Camp Trail Meals.  

ERIC Educational Resources Information Center

By planning menus, repackaging food, packing the right spices, and being creative with aluminum foil and zip-top plastic bags, there is no reason to eat a bland trail meal again. Gives ten recipes, some with options for varying the dish. Eight of them serve two campers, two serve four to six. (TD)

Cameron, Layne

1998-01-01

239

On the Trail of the Missing Ozone  

NSDL National Science Digital Library

Produced by EPA's Region 9 Office in San Francisco, California, this book provides an introduction into why we need the ozone layer, the causes of ozone depletion, and some of the actions the world is taking to correct the problem. We hope you enjoy joining our intrepid reporter Farley on the trail of the missing ozone!

U.S. Environmental Protection Agency (; )

2008-04-25

240

Certification trails and software design for testability  

NASA Technical Reports Server (NTRS)

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.

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

1993-01-01

241

Modulation of TRAIL Signaling for Cancer Therapy  

Microsoft Academic Search

Apoptosis, the cell's intrinsic death program, is a key regulator of tissue homeostasis, and an imbalance between cell death and proliferation may result in tumor formation. Also, killing of cancer cells by cytotoxic therapies such as chemotherapy, ?-irradiation or ligation of death receptors is predominantly mediated by triggering apoptosis in target cells. Tumor necrosis factor–related apoptosis-inducing ligans (TRAIL) is a

Simone Fulda; Klaus-Michael Debatin

2004-01-01

242

Food Stories Exhibition Trail Leader's Notes  

E-print Network

Food Stories Exhibition Trail Leader's Notes 1. Take a look at the stone fragment. Where do you a story about a celebration involving food? (No answer required) 3. This is a food hook from Papua New of grass, palm leaves and bamboo. The food hook would hang from the ceiling of the hut. Why do you think

Levi, Ran

243

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

USGS Publications Warehouse

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.

Holcombe, Tracy

2014-01-01

244

Role of serum TRAIL level and TRAIL apoptosis gene expression in multiple sclerosis and relation to brain atrophy.  

PubMed

One of the presumed pathological mechanisms of multiple sclerosis (MS) is the failure of apoptosis of autoreactive T lymphocytes. This study aimed to determine the relationship of the tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) mRNA gene expression ratio and serum TRAIL levels with MS and brain atrophy. This study was conducted on 53 relapsing-remitting Egyptian MS patients and 25 matched healthy volunteers. The expression of TRAIL in peripheral blood lymphocytes was analyzed by reverse transcription polymerase chain reaction, serum levels of soluble TRAIL (sTRAIL) were determined by enzyme-linked immunosorbent assay and brain MRI measured "black holes" and the bicaudate ratio as a measure of brain atrophy in all patients. The serum TRAIL level was lower in MS patients compared to controls but no difference was seen in the TRAIL mRNA gene expression ratio. No significant correlation was detected between the serum TRAIL level and the TRAIL mRNA expression ratio in either group. No statistically significant correlation was found between serum TRAIL levels or the TRAIL mRNA expression ratio with the number of black holes or the bicaudate ratio on MRI. Apoptosis of T lymphocytes is decreased in MS patients, which could be useful when designing treatments. There was no difference in the TRAIL mRNA gene expression ratio between MS patients and controls. PMID:24913933

Tawdy, Mohamed H; Abd El Nasser, Maged M; Abd El Shafy, Sanaa S; Nada, Mona A F; El Sirafy, Mohamed Nasr I; Magd, Amany Hussien Abol

2014-09-01

245

Targeting death receptor TRAIL-R2 by chalcones for TRAIL-induced apoptosis in cancer cells.  

PubMed

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

Szliszka, Ewelina; Jaworska, Dagmara; Ksek, Ma?gorzata; Czuba, Zenon P; Król, Wojciech

2012-01-01

246

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

PubMed Central

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

Szliszka, Ewelina; Jaworska, Dagmara; K?ósek, Ma?gorzata; Czuba, Zenon P.; Król, Wojciech

2012-01-01

247

H-Ras regulation of TRAIL death receptor mediated apoptosis.  

PubMed

TNF-related apoptosis-inducing ligand (TRAIL) induces apoptosis through the death receptors (DRs) 4 and/or 5 expressed on the cell surface. Multiple clinical trials are underway to evaluate the antitumor activity of recombinant human TRAIL and agonistic antibodies to DR4 or DR5. However, their therapeutic potential is limited by the high frequency of cancer resistance. Here we provide evidence demonstrating the role of H-Ras in TRAIL receptor mediated apoptosis. By analyzing the genome wide mRNA expression data of the NCI60 cancer cell lines, we found that H-Ras expression was consistently upregulated in TRAIL-resistant cell lines. By contrast, no correlation was found between TRAIL sensitivity and K-Ras expression levels or their mutational profiles. Notably, H-Ras upregulation associated with a surface deficiency of TRAIL death receptors. Selective inhibition of H-Ras activity in TRAIL-resistant cells restored the surface expression of both DR4 and DR5 without changing their total protein levels. The resulting cells became highly susceptible to both TRAIL and agonistic DR5 antibody, whereas K-Ras inhibition had little or no effect on TRAIL-induced apoptosis, indicating H-Ras plays a distinct role in the regulation of TRAIL death receptors. Further studies are warranted to determine the therapeutic potential of H-Ras-specific inhibitors in combination with TRAIL receptor agonists. PMID:25026275

Chen, Jun-Jie; Bozza, William P; Di, Xu; Zhang, Yaqin; Hallett, William; Zhang, Baolin

2014-07-15

248

Constituents of Amoora cucullata with TRAIL resistance-overcoming activity.  

PubMed

In search of bioactive natural products for overcoming TRAIL resistance from natural resources, we previously reported a number of active compounds. Bioassay-guided fractionation of mangrove, Amoora cucullata, collected from Sundarbans Mangrove Forest, Bangladesh, led to the isolation of four new compounds (1-4), along with seven known compounds (5-11). Of the isolates, compounds 1, 5, 8, and 9 showed TRAIL resistance-overcoming activity, among which 8 showed the most potent activity and enhanced TRAIL-induced apoptosis in TRAIL-resistant human gastric adenocarcinoma (AGS) cells through the activation of caspase-3/7, enhancing the expression of DR4 and DR5 mRNA in AGS cells. Cell death caused by the combined treatment of 8 and TRAIL was inhibited by human recombinant DR5/Fc and DR4/Fc chimera proteins, indicating that 8 sensitizes TRAIL-resistant AGS cells to TRAIL through the induction of DR4 and DR5. PMID:20571616

Ahmed, Firoj; Toume, Kazufumi; Sadhu, Samir K; Ohtsuki, Takashi; Arai, Midori A; Ishibashi, Masami

2010-08-21

249

Molecular Targets of TRAIL-Sensitizing Agents in Colorectal Cancer  

PubMed Central

Tumor necrosis factor (TNF)-related apoptosis inducing ligand (TRAIL), a member of the TNF superfamily, interacts with its functional death receptors (DRs) and induces apoptosis in a wide range of cancer cell types. Therefore, TRAIL has been considered as an attractive agent for cancer therapy. However, many cancers are resistant to TRAIL-based therapies mainly due to the reduced expression of DRs and/or up-regulation of TRAIL pathway-related anti-apoptotic proteins. Compounds that revert such defects restore the sensitivity of cancer cells to TRAIL, suggesting that combined therapies could help manage neoplastic patients. In this article, we will focus on the TRAIL-sensitizing effects of natural products and synthetic compounds in colorectal cancer (CRC) cells and discuss the molecular mechanisms by which such agents enhance the response of CRC cells to TRAIL. PMID:22942679

Stolfi, Carmine; Pallone, Francesco; Monteleone, Giovanni

2012-01-01

250

The Synergistic Effects of Low Dose Fluorouracil and TRAIL on TRAIL-Resistant Human Gastric Adenocarcinoma AGS Cells  

PubMed Central

The TNF-related apoptosis-inducing ligand (TRAIL) is a TNF family member which has been under intense focus because of its remarkable ability to induce apoptosis in malignant human cells while leaving normal cells unscathed. However, many cancer cells remain resistant to TRAIL. In this study, we had investigated the synergistic effects of low dose fluorouracil (5-Fu) and TRAIL on TRAIL-resistant human gastric adenocarcinoma AGS cells and explored the potential mechanisms. Cell viability was analyzed by sulforhodamine B (SRB) assay and the synergistic effects were evaluated by Jin's formula and confirmed by both morphological changes under inverted microscope and flow cytometry. The expression of TRAIL-R1 (death receptor 4, DR4), TRAIL-R2 (DR5), TRAIL-R3 (decoy receptor, DcR1), TRAIL-R4 (DcR2), procaspase-3, procaspase-8, and procaspase-9 was detected by western blotting. Our results showed that there were significant synergistic effects of low dose 5-Fu and TRAIL on TRAIL-resistant AGS cells, and this effect was supposed to be mediated by decreasing DcR2 expression and increasing DR5 expression. The extrinsic and intrinsic apoptosis pathways were both activated. The data suggest that combined treatment of low dose 5-Fu and TRAIL can be an effective therapeutic approach for gastric adenocarcinoma. PMID:24324958

Huang, Min; Ren, Daoling; He, Jianping; Zhao, Fen; Yi, Cheng; Huang, Ying

2013-01-01

251

Mating system shifts on the trailing edge  

PubMed Central

Background The trailing edges of species ranges are becoming a subject of increasing interest as the environment changes due to global warming. Trailing edge populations are likely to face extinction because of a decline in numbers and an inability to evolve new adaptations with sufficient speed. Discussions of character change in the trailing edge have focused on physiological, exomorphic and phenological traits. The mating pattern within populations has not been part of the discourse, in spite of the fact that the mating pattern may affect the ability of populations to respond to environmental change and to maintain their sizes. In this paper, the case is made that a substantial increase in self-fertilization rates may occur via plastic responses to stress. Scope and Conclusions Small populations on the trailing edge are especially vulnerable to environmental change because of inadequate levels of cross-fertilization. Evidence is presented that a deficiency of cross-seed production is due to inadequate pollinator services and a paucity of self-incompatibility alleles within populations. Evidence also is presented that if plants are self-compatible, self-fertilization may compensate in part for this deficiency through a stress-induced increase in levels of self-compatibility and stress-induced alterations in floral morphology that elevate self-pollination. Whereas increased self-fertility may afford populations the time to adapt to their changing environments, it can be concluded that increased selfing is not a panacea for the ills of environmental change, because it will lead to substantial reductions in genetic diversity, which may render adaptation unlikely. PMID:21980190

Levin, Donald A.

2012-01-01

252

Modulation of TRAIL Signaling for Cancer Therapy  

Microsoft Academic Search

Apoptosis, the cell’s intrinsic death program, is a key regulator of tissue homeostasis, and an imbalance between cell death\\u000a and proliferation may result in tumor formation. Also, killing of cancer cells by cytotoxic therapies such as chemotherapy,\\u000a UPgamma-irradiation, or ligation of death receptors is predominantly mediated by triggering apoptosis in target cells. Tumor\\u000a necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is

Simone Fulda; Klaus-Michael Debatin

253

The anomalous diffusion of meteor trails  

Microsoft Academic Search

Abstract. Radars frequently detect meteor trails created bythe,ablation of micro-meteoroids between70 and120 km altitude in the atmosphere. Plasma simulations show that densitygradientsattheedgesofmeteortrailsdrivegradient- drift instabilities which develop into waves with perturbed electric elds often exceeding hundreds of mV\\/m. These waves create an anomalous,cross-eld diusion that can ex- ceed the cross-eld (? B) ambipolar diusion,by an order of magnitude. The characteristics of

Lars P. Dyrud; Meers M. Oppenheim; Axel F. vom Endt

2001-01-01

254

Observations on Multiple Trailing Vortex Merger  

NASA Astrophysics Data System (ADS)

The merger of multiple trailing vortices is observed experimentally. Rectangular wing semi-spans of various aspect ratios are used to create wing-tip vortices in a miniature water towing tank. The wings are supported from a pair of streamlined struts positioned near the tank walls which are towed from the towing carriage. LIF and DPIV are the experimental measurement tools. Using multiple airfoils, up to 4 separate trailing vortices can be created in the tank at the same time. The vortices generated are of like sign (co-rotating). The effects of initial separation distance, circulation Reynolds number Re_?, relative vortex strength, and number of vortices (2, 3, or 4) are investigated. A single trailing vortex is used as a baseline. Chord-based Reynolds number Rec is varied from approximately 4 \\cdot 10^4 to 4 \\cdot 10^5 and Re_? is varied from approximately 5 \\cdot 10^3 to 3 \\cdot 10^5. As in previous observations,( Chen, Jacob, & Sava?), to appear in JFM. the merger of a pair of co-rotating vortices is observed in typically one orbit period. The extremes of Re_? show variations in the merger process while relative vortex stength has a large impact on merger details. The total circulation remains constant from roll-up completion through merger, as do kinetic energy and angular momentum. For 3 or 4 vortices, merger occurs between the closest vortices first; thereafter the system behaves similar to a co-rotating vortex pair.

Jacob, J. D.

1998-11-01

255

Transportation Energy Futures Series: Potential for Energy Efficiency Improvement Beyond the Light-Duty-Vehicle Sector  

SciTech Connect

Considerable research has focused on energy efficiency and fuel substitution options for light-duty vehicles, while much less attention has been given to medium- and heavy-duty trucks, buses, aircraft, marine vessels, trains, pipeline, and off-road equipment. This report brings together the salient findings from an extensive review of literature on future energy efficiency options for these non-light-duty modes. Projected activity increases to 2050 are combined with forecasts of overall fuel efficiency improvement potential to estimate the future total petroleum and greenhouse gas (GHG) emissions relative to current levels. This is one of a series of reports produced as a result of the Transportation Energy Futures (TEF) project, a Department of Energy-sponsored multi-agency project initiated to pinpoint underexplored strategies for abating GHGs and reducing petroleum dependence related to transportation.

Vyas, A. D.; Patel, D. M.; Bertram, K. M.

2013-03-01

256

Trail geometry gives polarity to ant foraging networks.  

PubMed

Pheromone trails are used by many ants to guide foragers between nest and food. But how does a forager that has become displaced from a trail know which way to go on rejoining the trail? A laden forager, for example, should walk towards the nest. Polarized trails would enable ants to choose the appropriate direction, thereby saving time and reducing predation risk. However, previous research has found no evidence that ants can detect polarity from the pheromone trail alone. Pharaoh's ants (Monomorium pharaonis) produce elaborate trail networks throughout their foraging environment. Here we show that by using information from the geometry of trail bifurcations within this network, foragers joining a trail can adaptively reorientate themselves if they initially walk in the wrong direction. The frequency of correct reorientations is maximized when the trail bifurcation angle is approximately 60 degrees, as found in natural networks. These are the first data to demonstrate how ant trails can themselves provide polarity information. They also demonstrate previously unsuspected sophistication in the organization and information content of networks in insect societies. PMID:15602563

Jackson, Duncan E; Holcombe, Mike; Ratnieks, Francis L W

2004-12-16

257

Experimental evaluation of certification trails using abstract data type validation  

NASA Technical Reports Server (NTRS)

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.

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

1993-01-01

258

Analyzing the influence of median cross-section design on highway safety using vehicle dynamics simulations.  

PubMed

Although vehicle dynamics simulations have long been used in vehicle design and crash reconstruction, their use for highway design is rare. This paper investigates the safety of highway medians through iterative simulations of off-road median encroachments. The commercially available software CarSim was used to simulate over one hundred thousand encroachments, representing the entire passenger vehicle fleet and a wide range of encroachment angles, departure speeds, steering inputs, and braking inputs. Each individual simulation output was then weighted using data from previous studies to reflect the probability of each specific accident scenario occurring in a real-life median encroachment. Results of this analysis illustrate the relative influence of median cross-section geometry on the resulting accident outcomes. The simulations indicate that the overall safety of a highway median depends on the occurrence of both vehicle rollover and median crossover events, and the cross-section shape, slope, and width are all shown to greatly affect each of these incidents. An evaluation of the simulation results was conducted with vehicle trajectories from previous experimental crash tests. Further assessment of the aggregate simulation results to actual crash data was achieved through comparison with several databases of crash statistics. Both efforts showed a strong agreement between the simulations and the real-life crash data. PMID:20728628

Stine, Jason S; Hamblin, Bridget C; Brennan, Sean N; Donnell, Eric T

2010-11-01

259

Regulation of Trail Receptor Expression in Human Melanoma  

Microsoft Academic Search

In previous studies we have shown that the level of expression of tumor necrosis factor-related apoptosis-inducing ligand\\u000a (TRAIL) death receptor R2 was a major determinant of the sensitivity of melanoma cell lines to TRAIL-induced apoptosis. Transcriptional\\u000a events regulating TRAIL death receptor expression have been the focus of much study, but our investigations point to a more\\u000a important role for posttranscriptional

Peter Hersey; Si Yi Zhang; Xu Dong Zhang

260

A survey of debris trails from short-period comets  

E-print Network

We observed 34 comets using the 24 micron camera on the Spitzer Space Telescope. Each image contains the nucleus and covers at least 10^6 km of each comet's orbit. Debris trails due to mm-sized or larger particles were found along the orbits of 27 comets; 4 comets had small-particle dust tails and a viewing geometry that made debris trails impossible to distinguish; and only 3 had no debris trail despite favorable observing conditions. There are now 30 Jupiter-family comets with known debris trails, of which 22 are reported in this paper for the first time. The detection rate is >80%, indicating that debris trails are a generic feature of short-period comets. By comparison to orbital calculations for particles of a range of sizes ejected over 2 yr prior to observation, we find that particles comprising 4 debris trails are typically mm-sized while the remainder of the debris trails require particles larger than this. The lower-limit masses of the debris trails are typically 10^11 g, and the median mass loss rate is 2 kg/s. The mass-loss rate in trail particles is comparable to that inferred from OH production rates and larger than that inferred from visible-light scattering in comae.

William T. Reach; Michael S. Kelley; Mark V. Sykes

2007-04-17

261

Development and evaluation of an in-vehicle information system  

SciTech Connect

In this paper, the authors introduce an In-Vehicle Information System (IVIS) which will manage messages from a variety of Advanced Traveler Information Services (ATIS) devices which can be installed in a road vehicle. The IVIS serves as the interface between the driver and the driving information environment. Increasingly, aftermarket systems, such as routing and navigation aids, are becoming available which can be added to vehicles to aid in travel and/or the conduct of business in the vehicle. The installation of multiple devices, each with its own driver interface, increases the likelihood of driver distraction and thus the risk of an accident. The goal of this project is the development of a fully-integrated IVIS which will filter, prioritize and display highway and vehicle information safely and efficiently, while also providing an integrated driver interface to a variety of ATIS information sources. Because these devices will be integrated into IVIS as components, they are referred to in this paper as IVIS subsystems. Such a system, using modern digital technology, will tailor information both to the driver`s needs and to the driving environment. A variety of other efforts, both in the Us and abroad, either have been completed or are nearing completion, and the results of these efforts will be incorporated into this present system. IVIS must perform three high level functions (Tufano, et al, 1997). It must (1) interact with (ATIS) subsystems, (2) management information, and (3) interact with the driver. To safely develop and evaluate such a device, a platform must be devised which permits testing in an off-road setting.

Spelt, P.F.; Tufano, D.R.; Knee, H.E.

1997-04-01

262

Safer Science: The Safety Legal Paper Trail  

NSDL National Science Digital Library

To avoid the potential for litigation, teachers need to be informed. They must know how to prevent accidents and should be proactive to protect both themselves and students from harm in the classroom. The following actions are recommended to help teachers maintain a safe working environment by protecting students from unreasonable risks of harm. Also, these actions will help teachers remain safe from litigation. If litigation does arise, these actions provide a paper trail that documents a teacher's efforts to prevent harm to students.

Ken Roy

2009-02-01

263

Correlation of turbulent trailing vortex decay data  

NASA Technical Reports Server (NTRS)

A correlation function, derived on the basis of self similar variable eddy viscosity decay, is introduced and utilized to correlate aircraft trailing vortex velocity data from ground and flight experiments. The correlation function collapses maximum tangential velocity data from scale model and flight tests to a single curve. The resulting curve clearly shows both the inviscid plateau and the downstream decay regions. A comparison between experimental data and numerical solution shows closer agreement with the variable eddy viscosity solution than the constant viscosity analytical solution.

Iversen, J. D.

1974-01-01

264

To Play Trail and Go Ape!  

E-print Network

B e d g e b u r y F o r e s t To Play Trail and Go Ape! National Cycle Network Route 18Enntrance oA21 Overflow Car Park TTo V enenen du u b e ucat y r forest o theTTo deB and Go Ape! oTTo d e B and Go Ape! railTo Play g d 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 A B C D E F G H I J

265

Reconnaissance observations of long-term natural vegetation recovery in the Cape Thompson region, Alaska, and additions to the checklist of flora  

Microsoft Academic Search

The diversity of disturbance types, landforms, vegetation and soils, together with the large, well-documented flora, makes Cape Thompson an ideal site to study long-term (20-year) environmental adjustments after impact. Man-caused disturbances there between 1958 and 1962 fall into three categories: runways, excavations and off-road vehicle trails. In addition, natural disturbance by frost action creates scars. Reestablished vegetation after 20 years

K. R. Everett; B. M. Murray; D. F. Murray; A. W. Johnson; A. E. Linkins; P. J. Webber

1985-01-01

266

Interior of shop, showing the reheat furnaces; the vehicle in ...  

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

Interior of shop, showing the reheat furnaces; the vehicle in the center is a charging machine the operator of which manipulates steel ingots in the furnace, as well as in the adjacent forging hammers - Bethlehem Steel Corporation, South Bethlehem Works, Tool Steel-Electric Furnace Shop, Along Lehigh River, North of Fourth Street, West of Minsi Trail Bridge, Bethlehem, Northampton County, PA

267

43 CFR 8343.1 - Standards.  

Code of Federal Regulations, 2012 CFR

...off-road vehicle may be operated on public lands unless equipped with brakes in good working condition. (b) No off-road vehicle...cutout, bypass, or similar device, or producing excessive noise exceeding Environmental Protection Agency standards,...

2012-10-01

268

43 CFR 8343.1 - Standards.  

Code of Federal Regulations, 2014 CFR

...off-road vehicle may be operated on public lands unless equipped with brakes in good working condition. (b) No off-road vehicle...cutout, bypass, or similar device, or producing excessive noise exceeding Environmental Protection Agency standards,...

2014-10-01

269

43 CFR 8343.1 - Standards.  

Code of Federal Regulations, 2013 CFR

...off-road vehicle may be operated on public lands unless equipped with brakes in good working condition. (b) No off-road vehicle...cutout, bypass, or similar device, or producing excessive noise exceeding Environmental Protection Agency standards,...

2013-10-01

270

43 CFR 8343.1 - Standards.  

Code of Federal Regulations, 2011 CFR

...off-road vehicle may be operated on public lands unless equipped with brakes in good working condition. (b) No off-road vehicle...cutout, bypass, or similar device, or producing excessive noise exceeding Environmental Protection Agency standards,...

2011-10-01

271

The Crooked Road: Virginia's Heritage Music Trail  

NSDL National Science Digital Library

The idea for Virginia's "Crooked Road" began to germinate in the minds of Virginians in January 2003. A number of public officials, musicians, and others were interested in an economic development strategy for the Appalachian region of southwestern Virginia, and they wanted to draw on the region's rich musical heritage. Over time, the project grew, and today it includes ten counties, three cities, ten towns, and four state agencies. This well-designed site allows visitors to learn about the trail, its music venues, the music itself, and the communities along the route. First-time visitors will want to start out in "The Trail" area. Here they can view an interactive map of the area, look over the calendar of events, and read about nearby attractions. The next stop should be "The Music". As one might imagine, there are clips of music from the Crooked Road, including favorites like "Old Time Fire on the Mountain". Finally, visitors shouldn't forget the "Communities" area, which contains profiles of the places where the songs come alive, such as Big Stone Gap and Damascus.

272

Leukemia . Author manuscript Controlling TRAIL-mediated caspase-3 activation  

E-print Network

Leukemia . Author manuscript Page /1 3 Controlling TRAIL-mediated caspase-3 activation Olivier ; Caspases ; metabolism ; Enzyme Activation ; drug effects ; Humans ; Leukemia ; enzymology ; pathology of ( Differential involvement ofLeukemia ` Bax and Bak in TRAIL-mediated apoptosis of leukemic T cells

Paris-Sud XI, Université de

273

36 CFR 7.100 - Appalachian National Scenic Trail.  

Code of Federal Regulations, 2010 CFR

...State-approved snowmobile trails in Maine, New Hampshire, Vermont, Massachusetts...The spur snowmobile route that leads from Maine Bureau of Parks and Lands Debsconeag Pond...that leads from Lake Hebron near Monson, Maine to the Maine Interconnecting Trail...

2010-07-01

274

View of blind curve along National Old Trails Road, about ...  

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

View of blind curve along National Old Trails Road, about 1,000 feet from top, facing north. - La Bajada Historic Trails and Roads, Approximately 1 mile East/Northeast of intersection of State Highway 16 and Indian Service Road 841, La Bajada, Santa Fe County, NM

275

Will human recreational activity on levee trails enhance carnivore activity?  

E-print Network

Will human recreational activity on levee trails enhance carnivore activity? Will human recreational activity on levee trails enhance carnivore activity? INTRODUCTION For people and terrestrial 2006, we conducted carnivore surveys in control and impact areas established along the levee (Figure 1

Johnson, Matthew

276

Hydrodynamic Trails Produced by Daphnia: Size and Energetics  

PubMed Central

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

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

2014-01-01

277

Go West: Imagining the Oregon Trail. [Lesson Plan].  

ERIC Educational Resources Information Center

In this lesson plan, students in grades 3-5 compare imagined travel experiences of their own with the actual experiences of 19th-century pioneers on the Oregon Trail. After the 4 lessons students will have: (1) learned about the pioneer experience on the Oregon Trail; (2) compared and contrasted modern-day travel experiences with those of the 19th…

National Endowment for the Humanities (NFAH), Washington, DC.

278

14. Roaring Fork Motor Nature Trail, Place of a thousand ...  

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

14. Roaring Fork Motor Nature Trail, Place of a thousand drips, view with three culvert pipes. - Great Smoky Mountains National Park Roads & Bridges, Roaring Fork Motor Nature Trail, Between Cherokee Orchard Road & U.S. Route 321, Gatlinburg, Sevier County, TN

279

Plasma wave excitation on meteor trails in the equatorial electrojet  

Microsoft Academic Search

The unusual properties of meteor echoes recently observed at Jicamarca (Chapin and Kudeki, 1994) are attributed to the growth and propagation of plasma irregularities along meteor trails deposited within the equatorial electrojet. It is suggested that trails at electrojet heights must carry intense discharge currents that excite two-stream and\\/or gradient drift instabilities for irregularity growth. The direction of electron motion

Elaine Chapin; Erhan Kudeki

1994-01-01

280

TRAIL-induced eradication of primary tumour cells from multiple myeloma patient bone marrows is not related to TRAIL receptor expression or prior chemotherapy  

Microsoft Academic Search

TNF-related apoptosis-inducing ligand (TRAIL) shares significant homology with CD95 (Fas) ligand and has the ability to induce apoptosis in sensitive cells through a caspase-mediated pathway. We have evaluated the activity of purified human recombinant soluble TRAIL (S-TRAIL, comprising residues 114–281; Biomol, Plymouth Meeting, PA, USA) and a leucine zipper construct of TRAIL (LZ-TRAIL; Immunex, Seattle WA, USA) against myeloma cell

LF Lincz; T-X Yeh; A Spencer

2001-01-01

281

Partially turbulated trailing edge cooling passages for gas turbine nozzles  

DOEpatents

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.

Thatcher, Jonathan Carl (Schenectady, NY); Burdgick, Steven Sebastian (Schenectady, NY)

2001-01-01

282

Trailing edge flow conditions as a factor in airfoil design  

NASA Technical Reports Server (NTRS)

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.

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

1984-01-01

283

United States Marine Corps light armored vehicle ride and shock mobility test  

SciTech Connect

Mobility on the battlefield has been a major concern since the beginning of modern warfare. How do you transport troops more efficiently, in the least amount of time, from place to place on the battlefield? In the early days of World War I, came the invention of the tank and different types of armored vehicles. These vehicles were very slow and moved over a limited variety of terrain. Today, with faster, more powerful armored vehicles, extended testing is being done to determine their ability to move over various types of terrain encountered on the modern battlefield. Along with this testing, studies are performed which take into account the effect of the ride on soldiers. It has been proven that a sustained rough ride, of over 6 watts of vertical absorbed power, will affect a soldier`s ability to fight, once he reaches the battle. As a result, different vehicles go through testing in various off-road terrain to determine which one can handle the roughest terrain, at the fastest speed, while transporting troops, without imposing large amounts of human vibration on the soldiers. This is done through ride and shock mobility tests.

Casterlow, D.; Salami, M.R. [North Carolina A and T State Univ., Greensboro, NC (United States). Dept. of Civil Engineering

1995-06-01

284

TRAIL: a tokamak rail gun limiter  

SciTech Connect

An attractive new limiter concept is investigated. The TRAIL (Tokamak Rail Gun Limiter) system impacts a stream of moderate velocity pellets (100 to 200 m/sec through the plasma edge region to absorb energy and define the plasma boundary. The pellets are recycled, after cooling, to the injector in an E-M mass accelerator. Heat fluxes of approx. 30,000 W/cm/sup 2/ can be readily accommodated by the pellets, with very low recirculating power requirements (approx. 0.1%) for the accelerator. The mass accelerator velocity requirements are well within the present state-of-the-art (several km/sec). Accelerators injecting pellets at approx. 1 km/sec can be used to control local plasma temperature and current profiles and to act as energy absorbers to shut down the plasma without damage to the first wall if a plasma disruption occurs.

Yu, W.S.; Powell, J.R.; Usher, J.L.

1980-01-01

285

Wallace Creek Interpretive Trail: A Geologic Guide  

NSDL National Science Digital Library

This set of guides covers the geology, seismology, hydrology, and physical geography of the San Andreas Fault in the area of Wallace Creek in San Luis Obispo County, California. Materials available here include a downloadable trail guide for Wallace Creek; an interactive guide with information on the earthquakes, the fault, and plate tectonics; a downloadable guide from the Geologic Society of America (GSA); and a downloadable self-guided automobile tour for the Carrizo Plain. There are also field exercises which instructors may find useful as class assignments to accompany class trips to the Wallace Creek site, and a link to a bulletin from the GSA that explores the research done at Wallace Creek and explains how the slip rate for the San Andreas fault was measured.

Aron Meltzner

286

Trailing Ballute Aerocapture: Concept and Feasibility Assessment  

NASA Technical Reports Server (NTRS)

Trailing Ballute Aerocapture offers the potential to obtain orbit insertion around a planetary body at a fraction of the mass of traditional methods. This allows for lower costs for launch, faster flight times and additional mass available for science payloads. The technique involves an inflated ballute (balloon-parachute) that provides aerodynamic drag area for use in the atmosphere of a planetary body to provide for orbit insertion in a relatively benign heating environment. To account for atmospheric, navigation and other uncertainties, the ballute is oversized and detached once the desired velocity change (Delta V) has been achieved. Analysis and trades have been performed for the purpose of assessing the feasibility of the technique including aerophysics, material assessments, inflation system and deployment sequence and dynamics, configuration trades, ballute separation and trajectory analysis. Outlined is the technology development required for advancing the technique to a level that would allow it to be viable for use in space exploration missions.

Miller, Kevin L.; Gulick, Doug; Lewis, Jake; Trochman, Bill; Stein, Jim; Lyons, Daniel T.; Wilmoth, Richard G.

2003-01-01

287

Active Management of Flap-Edge Trailing Vortices  

NASA Technical Reports Server (NTRS)

The vortex hazard produced by large airliners and increasingly larger airliners entering service, combined with projected rapid increases in the demand for air transportation, is expected to act as a major impediment to increased air traffic capacity. Significant reduction in the vortex hazard is possible, however, by employing active vortex alleviation techniques that reduce the wake severity by dynamically modifying its vortex characteristics, providing that the techniques do not degrade performance or compromise safety and ride quality. With this as background, a series of experiments were performed, initially at NASA Langley Research Center and subsequently at the Berlin University of Technology in collaboration with the German Aerospace Center. The investigations demonstrated the basic mechanism for managing trailing vortices using retrofitted devices that are decoupled from conventional control surfaces. The basic premise for managing vortices advanced here is rooted in the erstwhile forgotten hypothesis of Albert Betz, as extended and verified ingeniously by Coleman duPont Donaldson and his collaborators. Using these devices, vortices may be perturbed at arbitrarily long wavelengths down to wavelengths less than a typical airliner wingspan and the oscillatory loads on the wings, and hence the vehicle, are small. Significant flexibility in the specific device has been demonstrated using local passive and active separation control as well as local circulation control via Gurney flaps. The method is now in a position to be tested in a wind tunnel with a longer test section on a scaled airliner configuration. Alternatively, the method can be tested directly in a towing tank, on a model aircraft, a light aircraft or a full-scale airliner. The authors believed that this method will have significant appeal from an industry perspective due to its retrofit potential with little to no impact on cruise (devices tucked away in the cove or retracted); low operating power requirements; small lift oscillations when deployed in a time-dependent manner; and significant flexibility with respect to the specific devices selected.

Greenblatt, David; Yao, Chung-Sheng; Vey, Stefan; Paschereit, Oliver C.; Meyer, Robert

2008-01-01

288

Photometry of 1998/1999 Persistent Trails from Leonid Meteors  

NASA Astrophysics Data System (ADS)

Surface brightness and line emission rates are derived for two persistent trails from the 1998 and 1999 Leonid meteor showers. The trails are optically thin, and in places appear as cylinders with a very dark center. This center is roughly as wide as the bright emission walls, but is as dark as the sky background. This situation is not in agreement with the simple hollow-cylinder model of shell burning. The data was acquired at the Starfire Optical Range on Kirtland AFB. The instruments were guided by a human observer onto the lingering trails of the meteors. A 5 degree wide Xybion camera, attached to the headring of the telescope, recorded the scene. The University of Illinois' sodium lidar determined the distance to the persistent trails. A 200-W copper vapor laser (CVL) was also used in an attempt to measure back-scatter from particulates in the contrails of the Leonids. Almost all of the meteors that produced lingering trails greatly enhanced the naturally occurring sodium layer at 100 km. The lingering trails generally appeared as evanescent smoke rings that evolved rather quickly, with the path of the meteor marked by a double walled, optically thin tube. A 15-minute highlight video will be presented showing the evolution of the lingering trails as well as the lidar and the CVL probing them.

Milster, S. P.; Grime, B.; Drummond, J.; Fugate, R.; Kane, T. J.; Liu, A.; Papen, C. S.; Kelly, M. C.; Kruschwitz, C.

2000-05-01

289

Machine performance and site disturbance in skidding on designated trails  

SciTech Connect

Overstorey trees (predominantly western red cedar Thuja plicata) in a stand in Idaho were removed in 1981 using 4 machines and 2 methods: skidding whole trees on undesignated trails; and skidding tree lengths on trails designated in advance. A caterpillar 518 rubber-tyred skidder (RTS) handling whole trees on undesignated trails had the lowest cost and the highest production. An FMC 200 CA torsion-bar track machine (low ground pressure) was the most expensive because of high initial and operating costs, and high incidence of breakdowns. A caterpillar D6D rigid track, medium-horsepower crawler and an international TD-8E rigid track, low-horsepower crawler were intermediate in cost. Output was generally increased when tree lengths were skidded on designated trails. Again the RTS had the lowest cost, and the highest production on haulage distances up to about 900 feet. For longer haulage distances, the D6D hauled more tree-length logs on designated skid trails. For all machine types, 17% of the area of conventionally logged whole tree units and 9% of the units where tree-length logs were skidded on designated trails were calculated to be occupied by roads. Trail designation reduced machine damage to regeneration by about 5%. 3 references.

Olsen, E.D.; Seifert, J.C.W.

1984-01-01

290

Aerodynamic Analysis of Trailing Edge Enlarged Wind Turbine Airfoils  

NASA Astrophysics Data System (ADS)

The aerodynamic performance of blunt trailing edge airfoils generated from the DU- 91-W2-250, DU-97-W-300 and DU-96-W-350 airfoils by enlarging the thickness of trailing edge symmetrically from the location of maximum thickness to chord to the trailing edge were analyzed by using CFD and RFOIL methods at a chord Reynolds number of 3 × 106. The goal of this study is to analyze the aerodynamic performance of blunt trailing edge airfoils with different thicknesses of trailing edge and maximum thicknesses to chord. The steady results calculated by the fully turbulent k-? SST, transitional k-? SST model and RFOIL all show that with the increase of thickness of trailing edge, the linear region of lift is extended and the maximum lift also increases, the increase rate and amount of lift become limited gradually at low angles of attack, while the drag increases dramatically. For thicker airfoils with larger maximum thickness to chord length, the increment of lift is larger than that of relatively thinner airfoils when the thickness of blunt trailing edge is increased from 5% to 10% chord length. But too large lift can cause abrupt stall which is profitless for power output. The transient characteristics of blunt trailing edge airfoils are caused by blunt body vortices at low angles of attack, and by the combined effect of separation and blunt body vortices at large angles of attack. With the increase of thickness of blunt trailing edge, the vibration amplitudes of lift and drag curves increase. The transient calculations over-predict the lift at large angles of attack and drag at all angles of attack than the steady calculations which is likely to be caused by the artificial restriction of the flow in two dimensions.

Xu, Haoran; Shen, Wenzhong; Zhu, Weijun; Yang, Hua; Liu, Chao

2014-06-01

291

76 FR 5586 - California State Motor Vehicle and Nonroad Engine Pollution Control Standards; Mobile Cargo...  

Federal Register 2010, 2011, 2012, 2013, 2014

...certified on-road engines would be required if...certified off-road engine would be required, along...highest level verified diesel emission control strategy...with Tier 4 off-road engines or installation of a...reduction of emissions of diesel particulate...

2011-02-01

292

Trails of Kilovolt Ions Created by Subsurface Channeling  

SciTech Connect

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 the ion's subsurface channel.

Redinger, Alex; Standop, Sebastian; Michely, Thomas [II. Physikalisches Institut, Universitaet Koeln, Zuelpicherstrasse 77, D-50937 Koeln (Germany); Rosandi, Yudi; Urbassek, Herbert M. [Fachbereich Physik und Forschungszentrum OPTIMAS, Universitaet Kaiserslautern, Erwin-Schroedinger-Strasse, D-67663 Kaiserslautern (Germany)

2010-02-19

293

Polarization and scattering of a long-duration meteor trail  

NASA Astrophysics Data System (ADS)

High-power, large-aperture (HPLA) radars have been used over the past two decades to characterize the plasmas formed both around and behind meteoroids as they enter Earth's atmosphere. These plasmas, referred to as heads and trails, respectively, occur with relative frequency (peak head echo detection rate of ˜1/s) but are extremely diverse and have been difficult to define in a general sense. One particular type of plasma, referred to as the nonspecular trail, occurs when the meteoroid travels quasi-parallel to the radar beam with the radar beam lying quasi-perpendicular to the background magnetic field. Reflection is believed to occur from field-aligned irregularities (FAIs) that form after the trail becomes unstable. While FAI scattering pertains to the majority of nonspecular trails that are short in duration, a subset of these trails, referred to as long-duration trails, still remains open to interpretation. In this paper we present a case study analysis of a long-duration, nonspecular trail and its associated head echo detected with the Advanced Research Project Agency (ARPA) Long-Range Tracking and Identification Radar (ALTAIR), which is an HPLA radar. These data are unique in that they are high resolution (with monopulse angles), dual frequency, and, most importantly, dual polarized, which allows for unprecedented insight into the scattering process from both heads and trails. First, we determine the velocity and mass of the parent meteoroid, which is a particle weighing more than a milligram and is one of the largest meteoroids ever detected by ALTAIR. Second, we determine the peak plasma density and polarization of the head echo and characterize the unique, yet strong returns in the opposite polarization, which may be due to multiple scattering centers within the range gate. Finally, we examine the polarization properties of the trail and discuss the first conclusive evidence of polarization flipping along the trail striations, which we believe corresponds to sharp gradients at the edges of the trail related to turbulent mixing of a dusty plasma that is elongating along the magnetic field. We look into a new idea, namely, the notion that some nonspecular echoes might correspond to a high Schmidt number, dusty plasma, as is found in and above noctilucent clouds. Our results show how polarized return can aid in scattering diagnostics and that single polarization radars must be used with caution for determining head and trail plasma densities given that some of the return can occur in the “unexpected” channel.

Close, S.; Kelley, M.; Vertatschitsch, L.; Colestock, P.; Oppenheim, M.; Yee, J.

2011-01-01

294

78 FR 59368 - Notice of Joint Meeting for Captain John Smith Chesapeake National Historic Trail Advisory...  

Federal Register 2010, 2011, 2012, 2013, 2014

...National Historic Trail Advisory Council and Star-Spangled Banner National Historic Trail...Chesapeake National Historic Trail and the Star-Spangled Banner National Historic Trail...and waterways of the Chesapeake Bay. The Star-Spangled Banner National Historic...

2013-09-26

295

Chemical cues used by prairie rattlesnakes ( Crotalus viridis ) to follow trails of rodent prey  

Microsoft Academic Search

Each of 10 prairie rattlesnakes (Crotalus viridis) was exposed to three types of trails after striking rodent prey (Mus musculus). One trail was made with mouse urine, another was made with tap water, and the third consisted of materials from mouse integument. The snakes exhibited trailing behavior only when integumentary trails were available. It was concluded that prairie rattlesnakes do

David Chiszar; Ted Melcer; Robert Lee; Charles W. Radcliffe; David Duvall

1990-01-01

296

Effect of Trail Bifurcation Asymmetry and Pheromone Presence or Absence on Trail Choice by Lasius niger Ants  

PubMed Central

During foraging, ant workers are known to make use of multiple information sources, such as private information (personal memory) and social information (trail pheromones). Environmental effects on foraging, and how these interact with other information sources, have, however, been little studied. One environmental effect is trail bifurcation asymmetry. Ants forage on branching trail networks and must often decide which branch to take at a junction (bifurcation). This is an important decision, as finding food sources relies on making the correct choices at bifurcations. Bifurcation angle may provide important information when making this choice. We used a Y-maze with a pivoting 90° bifurcation to study trail choice of Lasius niger foragers at varying branch asymmetries (0°, [both branches 45° from straight ahead], 30° [branches at 30° and 60° from straight ahead], 45°, 60° and 90° [one branch straight ahead, the other at 90°]). The experiment was carried out either with equal amounts of trail pheromone on both branches of the bifurcation or with pheromone present on only one branch. Our results show that with equal pheromone, trail asymmetry has a significant effect on trail choice. Ants preferentially follow the branch deviating least from straight, and this effect increases as asymmetry increases (47% at 0°, 54% at 30°, 57% at 45°, 66% at 60° and 73% at 90°). However, when pheromone is only present on one branch, the graded effect of asymmetry disappears. Overall, however, there is an effect of asymmetry as the preference of ants for the pheromone-marked branch over the unmarked branch is reduced from 65%, when it is the less deviating branch, to 53%, when it is the more deviating branch. These results demonstrate that trail asymmetry influences ant decision-making at bifurcations and that this information interacts with trail pheromone presence in a non-hierarchical manner. PMID:25400307

Forster, Antonia; Czaczkes, Tomer J; Warner, Emma; Woodall, Tom; Martin, Emily; Ratnieks, Francis L W; Herberstein, M

2014-01-01

297

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

USGS Publications Warehouse

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.

Marion, Jeffrey L.; Leung, Yu-Fai

2011-01-01

298

Electric vehicles  

SciTech Connect

Quiet, clean, and efficient, electric vehicles (EVs) may someday become a practical mode of transportation for the general public. Electric vehicles can provide many advantages for the nation's environment and energy supply because they run on electricity, which can be produced from many sources of energy such as coal, natural gas, uranium, and hydropower. These vehicles offer fuel versatility to the transportation sector, which depends almost solely on oil for its energy needs. Electric vehicles are any mode of transportation operated by a motor that receives electricity from a battery or fuel cell. EVs come in all shapes and sizes and may be used for different tasks. Some EVs are small and simple, such as golf carts and electric wheel chairs. Others are larger and more complex, such as automobile and vans. Some EVs, such as fork lifts, are used in industries. In this fact sheet, we will discuss mostly automobiles and vans. There are also variations on electric vehicles, such as hybrid vehicles and solar-powered vehicles. Hybrid vehicles use electricity as their primary source of energy, however, they also use a backup source of energy, such as gasoline, methanol or ethanol. Solar-powered vehicles are electric vehicles that use photovoltaic cells (cells that convert solar energy to electricity) rather than utility-supplied electricity to recharge the batteries. This paper discusses these concepts.

Not Available

1990-03-01

299

Motor vehicle  

SciTech Connect

An improvement in a motor vehicle is described including: a vehicle body; a front road wheel disposed in the front part of the vehicle body; a rear road wheel disposed in the rear part of the vehicle body; an engine for driving at least either of the front and rear road wheels; and a steering wheel for steering at least either of the front and rear road wheels; comprising: detection means connected to the vehicle for detecting the transverse sliding angle of the vehicle body; and display means connected to the detection means for visually displaying the moving direction of the vehicle body on the basis of an output of the detection means; and the detection means comprises a first sensor for detecting the advancing speed of the vehicle, a second sensor for detecting the transverse acceleration of the vehicle, a third sensor for detecting the yawing velocity of the vehicle, and a processor for calculating the transverse sliding angle on the basis of the advancing speed, the transverse acceleration and the yawing velocity.

Furukawa, Y.; Sano, S.

1986-04-15

300

Electric vehicles  

NASA Astrophysics Data System (ADS)

Quiet, clean, and efficient, electric vehicles (EVs) may someday become a practical mode of transportation for the general public. Electric vehicles can provide many advantages for the nation's environment and energy supply because they run on electricity, which can be produced from many sources of energy such as coal, natural gas, uranium, and hydropower. These vehicles offer fuel versatility to the transportation sector, which depends almost solely on oil for its energy needs. Electric vehicles are any mode of transportation operated by a motor that receives electricity from a battery or fuel cell. EVs come in all shapes and sizes and may be used for different tasks. Some EVs are small and simple, such as golf carts and electric wheel chairs. Others are larger and more complex, such as automobile and vans. Some EVs, such as fork lifts, are used in industries. In this fact sheet, we will discuss mostly automobiles and vans. There are also variations on electric vehicles, such as hybrid vehicles and solar-powered vehicles. Hybrid vehicles use electricity as their primary source of energy, however, they also use a backup source of energy, such as gasoline, methanol or ethanol. Solar-powered vehicles are electric vehicles that use photovoltaic cells (cells that convert solar energy to electricity) rather than utility-supplied electricity to recharge the batteries. These concepts are discussed.

1990-03-01

301

NATLNATL''s Nature Trails: Take the Hammock Trail here!s Nature Trails: Take the Hammock Trail here! Hammocks are complex & dynamic ecosystemsHammocks are complex & dynamic ecosystems  

E-print Network

? Are all hammock forests the same? Hammock forests in the Southeast have been compared to the beech that occur when fields are abandoned, take the Old Field Nature Trail. In 2001 an outbreak of southern pine

Jawitz, James W.

302

Development of Variable Camber Continuous Trailing Edge Flap System  

NASA Technical Reports Server (NTRS)

This presentation describes the current status of the joint NASA/Boeing collaboration on the development of a variable camber continuous trailing edge flap system for use in wing shaping control for cruise drag reduction.

Urnes, Jim, Sr.; Nguyen, Nhan T.; Dykman, John

2012-01-01

303

170. View of large trail shelter built for the United ...  

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

170. View of large trail shelter built for the United States Forest Service by the Civilian Conservation Corps in 1938 on Craggy Knob. Facing northwest. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

304

30 CFR 77.602 - Permanent splicing of trailing cables.  

Code of Federal Regulations, 2010 CFR

...When permanent splices in trailing cables are made, they shall be: (a) Mechanically strong with adequate electrical conductivity; (b) Effectively insulated and sealed so as to exclude moisture; and, (c) Vulcanized or otherwise made with...

2010-07-01

305

125. Moses H. Cone Memorial Park. View of carriage trail ...  

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

125. Moses H. Cone Memorial Park. View of carriage trail and flat top mountain from cone cemetery. Looking north-northeast. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

306

15. Yankee Horse Ridge. View of the trail crossing the ...  

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

15. Yankee Horse Ridge. View of the trail crossing the Yankee Horse Railroad bed. Facing south. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

307

Effect of blunt trailing edge on rotor broadband noise  

NASA Astrophysics Data System (ADS)

The production of high-frequency broadband noise by turbulent vortex shedding from rotor blades with blunt trailing edges is investigated analytically. The derivation of the governing equations, analogous to that of Kim and George (1982) for boundary-layer/trailing-edge noise, is explained, and numerical results are compared with the experimental data of Hubbard et al. (1981) and Lowson et al. (1972) in graphs. It is shown that vortex-shedding noise is a significant component of blunt-trailing-edge rotor broadband noise and that the analytical method employed gives reasonable predictions. The need for a better empirical expression for the normalized spectrum and for more measurements of surface pressure fluctuations near blunt trailing edges is indicated.

Chou, S.-T.; George, A. R.

1986-08-01

308

The Shape of Trail Canyon Alluvial Fan, Death Valley  

NASA Technical Reports Server (NTRS)

A modified conic equation has been fit to high-resolution digital topographic data for Trail Canyon alluvial fan in Death Valley, California. Fits were accomplished for 3 individual fan units of different age.

Farr, Tom G.; Dohrenwend, John C.

1993-01-01

309

21 CFR 1311.215 - Internal audit trail.  

Code of Federal Regulations, 2010 CFR

... Internal audit trail. (a) The pharmacy application provider must establish...Attempted unauthorized access to the pharmacy application, or successful unauthorized access to the pharmacy application where the determination...

2010-04-01

310

21 CFR 1311.215 - Internal audit trail.  

Code of Federal Regulations, 2013 CFR

... Internal audit trail. (a) The pharmacy application provider must establish...Attempted unauthorized access to the pharmacy application, or successful unauthorized access to the pharmacy application where the determination...

2013-04-01

311

21 CFR 1311.215 - Internal audit trail.  

Code of Federal Regulations, 2014 CFR

... Internal audit trail. (a) The pharmacy application provider must establish...Attempted unauthorized access to the pharmacy application, or successful unauthorized access to the pharmacy application where the determination...

2014-04-01

312

Audit trails in the Aeolus distributed security platform  

E-print Network

This thesis provides a complete design and implementation of audit trail collection and storage for Aeolus, a distributed security platform based on information flow control. An information flow control system regulates ...

Popic, Victoria

2010-01-01

313

Audit Trails in the Aeolus Distributed Security Platform  

E-print Network

This thesis provides a complete design and implementation of audit trail collection and storage for Aeolus, a distributed security platform based on information flow control. An information flow control system regulates ...

Popic, Victoria

2010-09-29

314

30 CFR 75.826 - High-voltage trailing cables.  

Code of Federal Regulations, 2010 CFR

...Resources 1 2010-07-01 2010-07-01 false High-voltage trailing cables. 75.826 Section...SAFETY STANDARDS-UNDERGROUND COAL MINES Underground High-Voltage Distribution High-Voltage Longwalls § 75.826...

2010-07-01

315

LA-UR-14-22379 Trails Management at LANL  

E-print Network

in times of high fire danger. In addition, trail use has increased due to social media and restrictions Alamos National Laboratory (LANL) has been considered one of the benefits of working and living in Los

316

30 CFR 57.12088 - Splicing trailing cables.  

Code of Federal Regulations, 2014 CFR

...LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Electricity Underground Only § 57.12088 Splicing trailing cables. No splice, except a vulcanized splice or its...

2014-07-01

317

30 CFR 57.12088 - Splicing trailing cables.  

Code of Federal Regulations, 2010 CFR

...LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Electricity Underground Only § 57.12088 Splicing trailing cables. No splice, except a vulcanized splice or its...

2010-07-01

318

30 CFR 56.12003 - Trailing cable overload protection.  

Code of Federal Regulations, 2010 CFR

...DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56.12003 Trailing cable overload protection. Individual overload protection or short circuit protection shall...

2010-07-01

319

30 CFR 57.12003 - Trailing cable overload protection.  

Code of Federal Regulations, 2014 CFR

...LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Electricity Surface and Underground § 57.12003 Trailing cable overload protection. Individual overload protection or...

2014-07-01

320

30 CFR 57.12088 - Splicing trailing cables.  

Code of Federal Regulations, 2011 CFR

...LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Electricity Underground Only § 57.12088 Splicing trailing cables. No splice, except a vulcanized splice or its...

2011-07-01

321

30 CFR 57.12088 - Splicing trailing cables.  

Code of Federal Regulations, 2012 CFR

...LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Electricity Underground Only § 57.12088 Splicing trailing cables. No splice, except a vulcanized splice or its...

2012-07-01

322

30 CFR 56.12003 - Trailing cable overload protection.  

Code of Federal Regulations, 2014 CFR

...DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56.12003 Trailing cable overload protection. Individual overload protection or short circuit protection shall...

2014-07-01

323

30 CFR 56.12003 - Trailing cable overload protection.  

Code of Federal Regulations, 2011 CFR

...DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56.12003 Trailing cable overload protection. Individual overload protection or short circuit protection shall...

2011-07-01

324

Curve of Western Maryland Rail Trail west of Hancock, milepost ...  

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

Curve of Western Maryland Rail Trail west of Hancock, milepost 117 vicinity, looking west. - Western Maryland Railway, Cumberland Extension, Pearre to North Branch, from WM milepost 125 to 160, Pearre, Washington County, MD

325

Radio polarisation measurements of meteor trail echoes with BRAMS  

NASA Astrophysics Data System (ADS)

BRAMS, the Belgian RAdio Meteor Stations, is a network of radio receiving stations using forward scattering techniques to detect and characterize meteoroids. One of the receiving stations located in Uccle is sensitive to all kind of polarisation. We present the preliminary radio polarisation measurements of meteor trail echoes and discuss how these data can be used to retrieve physical information about the meteor trail (e.g. ionisation).

Lamy, H.; Ranvier, S.; Anciaux, M.

2012-09-01

326

GRASSLAND SONGBIRD ABUNDANCE ALONG ROADS AND TRAILS IN SOUTHERN SASKATCHEWAN  

Microsoft Academic Search

We conducted roadside and trail-side point count surveys to determine whether grassland bird abundance differs along ditched and non-ditched sampling points in south- western Saskatchewan. Savannah and Vesper Sparrows were more abundant along roads, while Baird's Sparrows, Chestnut-collared Longspurs, and Sprague's Pipits were more abun- dant along trails. Clay-colored Sparrows, Horned Larks, and Western Meadowlarks were de- tected equally along

GLENN C. SUTTER; STEPHEN K. DAVIS; DAVID C. DUNCAN

327

Big Thicket National Preserve: Trails to the Future  

E-print Network

Capstone Project The George Bush School of Government and Public Service Texas A&M University Big Thicket National Preserve: Trails to the Future By Luke Anderson Chris Allen Leah Elrod Melissa Forbes Hannah Harbin Diann Strom Big... Thicket National Preserve: Trails to the Future Capstone Project The George Bush School of Government and Public Service Texas A&M University For questions and additional information, contact Dr. Carol L. Silva, clsilva...

Anderson, Luke; Allen, Chris; Elrod, Leah; Forbes, Melissa; Harbin, Hannah; Stromm, Diann

2003-01-01

328

Combined modality therapy with TRAIL or agonistic death receptor antibodies  

PubMed Central

Molecularly targeted therapies, such as antibodies and small molecule inhibitors have emerged as an important breakthrough in the treatment of many human cancers. One targeted therapy under development is tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) due to its ability to induce apoptosis in a variety of human cancer cell lines and xenografts, while lacking toxicity in most normal cells. TRAIL and apoptosis-inducing agonistic antibodies to the TRAIL death receptors have been the subject of many preclinical and clinical studies in the past decade. However, the sensitivity of individual cancer cell lines of a particular tumor type to these agents varies from highly sensitive to resistant. Various chemotherapy agents have been shown to enhance the apoptosis-inducing capacity of TRAIL receptor-targeted therapies and induce sensitization of TRAIL-resistant cells. This review provides an overview of the mechanisms associated with chemotherapy enhancement of TRAIL receptor-targeted therapies including modulation of the apoptotic (death receptor expression, FLIP and Bcl-2 or inhibitors of apoptosis [IAP] families) as well as cell signaling (NF?B, Akt, p53) pathways. These mechanisms will be important in establishing effective combinations to pursue clinically and in determining relevant targets for future cancer therapies. PMID:21263219

Amm, Hope M; Oliver, Patsy G; Lee, Choo Hyung; Li, Yufeng

2011-01-01

329

Trail Marking by Larvae of the Cactus Moth, Cactoblastis cactorum  

PubMed Central

The cactus moth, Cactoblastis cactorum (Berg) (Lepidoptera: Pyralidae), spends most of its larval life feeding within the cladodes of Opuntia cactuses, but the gregarious caterpillars begin their life outside the plant, and in the later instars make intermittent excursions over plant surfaces to access new cladodes and to thermoregulate. The study reported here showed that when the caterpillars move en masse, they mark and follow trails that serve to keep the cohort together. Artificial trails prepared from hexane extracts of the caterpillar's paired mandibular glands were readily followed by the caterpillars. The glands are remarkably large, and their fluid contents, which constitute approximately 1% of the total wet mass of a caterpillar, are secreted onto the substrate as they move. Although the caterpillars also lay down copious quantities of silk, the material in itself neither elicits trail following nor is it a requisite component of pathways that elicit trail following. Previous analyses of the mandibular glands of other species of pyralid caterpillars showed that they contain a series of structurally distinct 2-acyl-1,3 cyclohexane diones. Chemical analysis indicates that the glands of C. cactorum contain structurally similar compounds, and bioassays indicate that trail following occurs in response to these chemicals. While the mandibular glands' fluids have been shown to act as semiochemicals, effecting both interspecific and intraspecific behavior in other species of pyralids, the present study is the first to report their use as a trail pheromone. PMID:25373211

Fitzgerald, Terrence D.; Wolfin, Michael; Rossi, Frank; Carpenter, James E.; Pescador-Rubio, Alfonso

2014-01-01

330

Trail marking by larvae of the cactus moth, Cactoblastis cactorum.  

PubMed

The cactus moth, Cactoblastis cactorum (Berg) (Lepidoptera: Pyralidae), spends most of its larval life feeding within the cladodes of Opuntia cactuses, but the gregarious caterpillars begin their life outside the plant, and in the later instars make intermittent excursions over plant surfaces to access new cladodes and to thermoregulate. The study reported here showed that when the caterpillars move en masse, they mark and follow trails that serve to keep the cohort together. Artificial trails prepared from hexane extracts of the caterpillar's paired mandibular glands were readily followed by the caterpillars. The glands are remarkably large, and their fluid contents, which constitute approximately 1% of the total wet mass of a caterpillar, are secreted onto the substrate as they move. Although the caterpillars also lay down copious quantities of silk, the material in itself neither elicits trail following nor is it a requisite component of pathways that elicit trail following. Previous analyses of the mandibular glands of other species of pyralid caterpillars showed that they contain a series of structurally distinct 2-acyl-1,3 cyclohexane diones. Chemical analysis indicates that the glands of C. cactorum contain structurally similar compounds, and bio- assays indicate that trail following occurs in response to these chemicals. While the mandibular glands' fluids have been shown to act as semiochemicals, effecting both interspecific and intra- specific behavior in other species of pyralids, the present study is the first to report their use as a trail pheromone. PMID:25373211

Fitzgerald, Terrence D; Wolfin, Michael; Rossi, Frank; Carpenter, James E; Pescador-Rubio, Alfonso

2014-01-01

331

A star trail model of the galactic center snake  

NASA Astrophysics Data System (ADS)

The filamentary synchrotron radio source G359.1-0.2, otherwise known as 'the Snake,' lies close to the center of the Galaxy. We suggest that it is the result of a star trail which intersected the expanding shock of a supernova remnant (SNR). The shock of the SNR traveled preferentially up the trail, accelerating electrons which produce the observed synchrotron radiation. A pressure-balance model for the expansion of the trail into the ambient interstellar medium is used to find values for the wind speed and mass-loss rate of the star that produces such a trail. It is shown that the energy of the SNR shock could supply the energy of the relativistic electrons of the Snake. This model places tight constraints on the expansion of the trail due to the transverse momentum imparted to it by the SNR shock propagating along it. It is found that for the star trail system to last long enough to form the source we observe, the relative parsec-scale motions of the interstellar medium in the vicinity of the Snake must be lower than the measured turbulent velocities. The strongest argument in favor of this model is that it accounts naturally for the high collimation of the Snake.

Nicholls, Jennifer; Le Strange, E. T.

1995-04-01

332

Robust water hazard detection for autonomous off-road navigation  

Microsoft Academic Search

Existing water hazard detection methods usually fail when the features of water surfaces are greatly changed by the surroundings,\\u000a e.g., by a change in illumination. This paper proposes a novel algorithm to robustly detect different kinds of water hazards\\u000a for autonomous navigation. Our algorithm combines traditional machine learning and image segmentation and uses only digital\\u000a cameras, which are usually affordable,

Tuo-zhong Yao; Zhi-yu Xiang; Ji-lin Liu

2009-01-01

333

Perception of Environment Properties Relevant for Off-road Navigation  

E-print Network

of disasters or accidents. Furthermore, industries like agriculture and forestry benefit from efficient, robust their tasks unsupervised. But navigation in unknown, unstructured and thus also dangerous environ- ment

Berns, Karsten

334

AN ANALYSIS OF THE IMPACT OF SPORTS UTILITY VEHICLES IN THE UNITED STATES  

SciTech Connect

During the 1990s, sport utility vehicles (SUVs) became the fastest growing segment of the auto industry, especially those in the medium-size category. In 1999, SUV sales reached almost 19% of the total light vehicle market and the mix of SUVs on the road, as measured by registration data, was about 8.7%. This immense popularity has been called by some a passing fad--vehicle purchases based on the SUV ''image''. But the continued yearly increases in SUV sales seem to indicate a more permanent trend. Additional explanations for SUV popularity include the general economic well being in the United States, a perception of safety, and ''utility''. Generally larger and heavier than the typical automobile, SUVs require more fuel per mile to operate and produce greater amounts of pollutants. They are also driven further annually than are automobiles of the same vintage, a fact that exacerbates the fuel-use and emission problems. Although buyers believe that SUVs are safer than automobiles which they are in some cases, SUVs are more prone to roll-overs than are automobiles. In addition, SUVs, with their higher bumpers and greater weight, may be a threat to other vehicles on the highway, especially in side-impact crashes. With sales projected to grow to over 3 million units per year beginning in 2001, SUVs show no sign of decreasing in popularity. These vehicles are used primarily for general mobility, rather than off-road activities. An emphasis on better fuel economy and improved emissions control could address environmental and oil dependency concerns. In fact, recently, two vehicle manufacturers announced intentions of improving the fuel economy of their SUVs in the next few years. Also, tests simulating crashes involving automobiles and SUVs could provide valuable data for identifying potential safety design issues. It is clear that automobiles and SUVs will be sharing the highways for years to come.

Davis, S.C.

2000-08-16

335

Vehicle systems  

NASA Technical Reports Server (NTRS)

Perspectives of the subpanel on expendable launch vehicle structures and cryotanks are: (1) new materials which provide the primary weight savings effect on vehicle mass/size; (2) today's investment; (3) typically 10-20 years to mature and fully characterize new materials.

Bales, Tom; Modlin, Tom; Suddreth, Jack; Wheeler, Tom; Tenney, Darrel R.; Bayless, Ernest O.; Lisagor, W. Barry; Bolstad, Donald A.; Croop, Harold; Dyer, J.

1993-01-01

336

Trailed Spectra of Bright Spectrophotometric Standard Stars  

NASA Astrophysics Data System (ADS)

The IUE archives is an extensive and growing database of UV spectra of a wide variety of astronomical objects. The usefulness of the archives will be greatly enhanced by the presence of a number of wellobserved standard stars including those which define the visual wavelength absolute flux calibrations. Observation of ground-based spectrophotometric standards by IUE will be useful for providing a selfconsistent flux calibration for bright stars and for permitting direct comparisons with fainter standards for future missions, already in the archives, on the IUE system. New observing techniques now make it possible for IUE to obtain well-exposed spectra of these bright stars. However, this observing method is one of the few which may not be possible if IUE were to lose another gyro and the backup control mode, now under development, were used. We propose to obtain short and long wavelength spectra for four of the brightest spectrophotometric standard stars which have either not been observed with with IUE or are poorly represented in the IUE archives. Over a number of years these stars have been observed and defined as standards by a number of ground based observers including Oke(1964), Breger (1976), Stone(1977), Oke and Gunn (1983), and Taylor (1984). The primary standard has been Vega with 109 Vir as an alternate (Davis Philip and Hayes 1984). By combining trailed and point source spectra, ultraviolet absolute flux distributions will be obtained for the 1200-3200 A interval. A comparison will be made of Alpha Lyr and 109 Vir with the nearby star Alpha CMA A, which has a well-determined distance and measured radius. The suspected low-level intermittent variability of Alpha Lyr is not believed to pose major problems for our analysis.

Pitts, Ronald E.

337

Using certification trails to achieve software fault tolerance  

NASA Technical Reports Server (NTRS)

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.

Sullivan, Gregory F.; Masson, Gerald M.

1993-01-01

338

Experimental evaluation of the certification-trail method  

NASA Technical Reports Server (NTRS)

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.

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

1993-01-01

339

Comparison of the properties of leading and trailing sunspots  

NASA Astrophysics Data System (ADS)

The magnetic properties of leading and trailing sunspots were compared based on SDO/HMI and SDO/AIA data with a high spatial resolution for the growth phase and maximum of cycle 24. The properties of the solar atmosphere above sunspots are also discussed independently for both of these sunspot types. It was shown that the contrast in the He II 304 ( C 304) line above the umbra of leading and single sunspots is on average smaller than such a contrast above the umbra of trailing sunspots and on average weakly depends on the umbra area for both C 304 sunspot types. It was established that the minimal angle between the field direction and the normal to the solar surface at the field measurement site is smaller in leading sunspots than in trailing ones (?min - ls < ?min - fs ) in 84% of the considered magnetically connected "leading-trailing" sunspot pairs, and a positive correlation exists between angles ?min - ls and ?min - fs . It was found that the C 304 contrast increases with decreasing ?min - ls, fs for leading and trailing sunspots, and the C 304 - ls / C 304 - fs ratio on average decreases with increasing ?min - ls /?min - fs ratio. The dependences of the maximal and average magnetic induction values in an umbra on the umbra area were constructed for the first time and compared independently for leading and trailing sunspots. It was concluded that the maximal and average magnetic field values do not vanish when the umbra area decreases to very small values. In all cases the magnetic field in leading and single sunspots is larger than in trailing ones.

Zagainova, Yu. S.; Fainshtein, V. G.; Obridko, V. N.

2015-01-01

340

Msi1 confers resistance to TRAIL by activating ERK in liver cancer cells.  

PubMed

To investigate TRAIL resistance mechanisms in hepatocellular carcinoma (HCC), we isolated a stable TRAIL-resistant sub-population of the HCC cell line LH86, designated LH86-TR. Differential activation of AKT was not responsible for acquisition of TRAIL resistance. Cells with both congenital and acquired resistance to TRAIL exhibited increased Msi1 expression, which conferred TRAIL resistance by activating ERK. Forced expression of Msi1 decreased the sensitivity of HCC cells to TRAIL both in vitro and in vivo. Conversely, shRNA-mediated depletion of Msi1 enhanced TRAIL efficacy. SiRNA-mediated depletion of ERK overcame TRAIL resistance. Hence, we conclude that Msi1 is a mediator of TRAIL resistance in HCC cells. PMID:25747387

Liu, Nianli; Chen, Tianran; Wang, Xiaohong; Yang, Darong; Xue, Binbin; Zhu, Haizhen

2015-04-01

341

Salinomycin Potentiates the Cytotoxic Effects of TRAIL on Glioblastoma Cell Lines  

PubMed Central

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has been reported to exhibit therapeutic activity in cancer. However, many tumors remain resistant to treatment with TRAIL. Therefore, small molecules that potentiate the cytotoxic effects of TRAIL could be used for combinatorial therapy. Here we found that the ionophore antibiotic salinomycin acts in synergism with TRAIL, enhancing TRAIL-induced apoptosis in glioma cells. Treatment with low doses of salinomycin in combination with TRAIL augmented the activation of caspase-3 and increased TRAIL-R2 cell surface expression. TRAIL-R2 upmodulation was required for mediating the stimulatory effect of salinomycin on TRAIL-mediated apoptosis, since it was abrogated by siRNA-mediated TRAIL-R2 knockdown. Salinomycin in synergism with TRAIL exerts a marked anti-tumor effect in nude mice xenografted with human glioblastoma cells. Our results suggest that the combination of TRAIL and salinomycin may be a useful tool to overcome TRAIL resistance in glioma cells and may represent a potential drug for treatment of these tumors. Importantly, salinomycin+TRAIL were able to induce cell death of well-defined glioblastoma stem-like lines. PMID:24740347

Calzolari, Alessia; Saulle, Ernestina; De Angelis, Maria Laura; Pasquini, Luca; Boe, Alessandra; Pelacchi, Federica; Ricci-Vitiani, Lucia; Baiocchi, Marta; Testa, Ugo

2014-01-01

342

Salinomycin potentiates the cytotoxic effects of TRAIL on glioblastoma cell lines.  

PubMed

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has been reported to exhibit therapeutic activity in cancer. However, many tumors remain resistant to treatment with TRAIL. Therefore, small molecules that potentiate the cytotoxic effects of TRAIL could be used for combinatorial therapy. Here we found that the ionophore antibiotic salinomycin acts in synergism with TRAIL, enhancing TRAIL-induced apoptosis in glioma cells. Treatment with low doses of salinomycin in combination with TRAIL augmented the activation of caspase-3 and increased TRAIL-R2 cell surface expression. TRAIL-R2 upmodulation was required for mediating the stimulatory effect of salinomycin on TRAIL-mediated apoptosis, since it was abrogated by siRNA-mediated TRAIL-R2 knockdown. Salinomycin in synergism with TRAIL exerts a marked anti-tumor effect in nude mice xenografted with human glioblastoma cells. Our results suggest that the combination of TRAIL and salinomycin may be a useful tool to overcome TRAIL resistance in glioma cells and may represent a potential drug for treatment of these tumors. Importantly, salinomycin+TRAIL were able to induce cell death of well-defined glioblastoma stem-like lines. PMID:24740347

Calzolari, Alessia; Saulle, Ernestina; De Angelis, Maria Laura; Pasquini, Luca; Boe, Alessandra; Pelacchi, Federica; Ricci-Vitiani, Lucia; Baiocchi, Marta; Testa, Ugo

2014-01-01

343

Meteor trail characteristics observed by high time resolution lidar  

NASA Astrophysics Data System (ADS)

We report and analyse the characteristics of 1382 meteor trails based on a sodium data set of ~ 680 h. The observations were made at Yanqing (115.97° E, 40.47° N), China by a ground-based Na fluorescence lidar. The temporal resolution of the raw profiles is 1.5 s and the altitude resolution is 96 m. We discover some characteristics of meteor trails different from those presented in previous reports. The occurrence heights of the trails follow a double-peak distribution with the peaks at ~ 83.5 km and at ~ 95.5 km, away from the peak height of the regular Na layer. 4.7% of the trails occur below 80 km, and 3.25% above 100 km. 75% of the trails are observed in only one 1.5 s profile, suggesting that the dwell time in the laser beam is not greater than 1.5 s. The peak density of the trails as a function of height is similar to that of the background sodium layer. The raw occurrence height distribution is corrected taking account of three factors which affect the relative lifetime of a trail as a function of height: the meteoroid velocity (which controls the ratio of Na/Na+ ablated); diffusional spreading of the trail; and chemical removal of Na. As a result, the bi-modal distribution is more pronounced. Modelling results show that the higher peak corresponds to a meteoroid population with speeds between 20 and 30 km s-1, whereas the lower peak should arise from much slower particles in a near-prograde orbit. It is inferred that most meteoroids in this data set have masses of ~ 1 mg, in order for ablation to produce sufficient Na atoms to be detected by lidar. Finally, the evolution of longer-duration meteor trails is investigated. Signals at each altitude channel consist of density enhancement bursts with the growth process usually faster than the decay process, and there exists a progressive phase shift among these altitude channels.

Liu, Y. J.; Plane, J. M. C.; Clemesha, B. R.; Wang, J. H.; Cheng, X. W.

2014-10-01

344

Center determination for trailed sources in astronomical observation images  

NASA Astrophysics Data System (ADS)

Images with trailed sources can be obtained when observing near-Earth objects, such as small astroids, space debris, major planets and their satellites, no matter the telescopes track on sidereal speed or the speed of target. The low centering accuracy of these trailed sources is one of the most important sources of the astrometric uncertainty, but how to determine the central positions of the trailed sources accurately remains a significant challenge to image processing techniques, especially in the study of faint or fast moving objects. According to the conditions of one-meter telescope at Weihai Observatory of Shandong University, moment and point-spread-function (PSF) fitting were chosen to develop the image processing pipeline for space debris. The principles and the implementations of both two methods are introduced in this paper. And some simulated images containing trailed sources are analyzed with each technique. The results show that two methods are comparable to obtain the accurate central positions of trailed sources when the signal to noise (SNR) is high. But moment tends to fail for the objects with low SNR. Compared with moment, PSF fitting seems to be more robust and versatile. However, PSF fitting is quite time-consuming. Therefore, if there are enough bright stars in the field, or the high astronometric accuracy is not necessary, moment is competent. Otherwise, the combination of moment and PSF fitting is recommended.

Du, Jun Ju; Hu, Shao Ming; Chen, Xu; Guo, Di Fu

2014-11-01

345

Structural design of morphing trailing edge actuated by SMA  

NASA Astrophysics Data System (ADS)

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.

Wang, Qi; Xu, Zhiwei; Zhu, Qian

2013-09-01

346

Leading and Trailing Anvil Clouds of West African Squall Lines  

NASA Technical Reports Server (NTRS)

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.

Centrone, Jasmine; Houze, Robert A.

2011-01-01

347

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

PubMed Central

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

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

348

The Dust Trail of Comet 67P/Churyumov-Gerasimenko  

E-print Network

We report the detection of comet 67P/Churyumov-Gerasimenko's dust trail and nucleus in 24 micron Spitzer Space Telescope images taken February 2004. The dust trail is not found in optical Palomar images taken June 2003. Both the optical and infrared images show a distinct neck-line tail structure, offset from the projected orbit of the comet. We compare our observations to simulated images using a Monte Carlo approach and a dynamical model for comet dust. We estimate the trail to be at least one orbit old (6.6 years) and consist of particles of size >~100 micron. The neck-line is composed of similar sized particles, particles of size but younger in age. Together, our observations and simulations suggest grains 100 micron and larger in size dominate the total mass ejected from the comet. The radiometric effective radius of the nucleus is 1.87 +/- 0.08 km, derived from the Spitzer observation. The Rosetta spacecraft is expected to arrive at and orbit this comet in 2014. Assuming the trail is comprised solely of 1 mm radius grains, we compute a low probability (~10^-3) of a trail grain impacting with Rosetta during approach and orbit insertion.

Michael S. Kelley; William T. Reach; David J. Lien

2007-09-06

349

Study of the Correlation between the Performances of Lunar Vehicle Wheels Predicted by the Nepean Wheeled Vehicle Performance Model and Test Data  

NASA Technical Reports Server (NTRS)

This paper describes the results of a study of the correlation between the performances of wheels for lunar vehicles predicted using the Nepean wheeled vehicle performance model (NWVPM), developed under the auspices of Vehicle Systems Development Corporation, Ottawa, Canada, and the corresponding test data presented in Performance evaluation of wheels for lunar vehicles , Technical Report M-70-2, prepared for George C. Marshall Space Flight Center, National Aeronautics and Space Administration (NASA), USA, by the US Army Engineer Waterways Experiment Station (WES). The NWVPM was originally developed for design and performance evaluation of terrestrial off-road wheeled vehicles. The purpose of this study is to assess the potential of the NWVPM for evaluating wheel candidates for the new generation of extra-terrestrial vehicles. Two versions of a wire-mesh wheel and a hoop-spring wheel, which were considered as candidates for lunar roving vehicles for the NASA Apollo program in the late 1960s, together with a pneumatic wheel were examined in this study. The tractive performances of these wheels and of a 464 test vehicle with the pneumatic wheels on air-dry sand were predicted using the NWVPM and compared with the corresponding test data obtained under Earth s gravity and previously documented in the above-named report. While test data on wheel or vehicle performances obtained under Earth s gravity may not necessarily be representative of those on extra-terrestrial bodies, because of the differences in gravity and in environmental conditions, such as atmospheric pressure, it is still a valid approach to use test data obtained under Earth s gravity to evaluate the predictive capability of the NWVPM and its potential applications to predicting wheel or wheeled rover performances on extra-terrestrial bodies. Results of this study show that, using the ratio (P20/W) of the drawbar pull to normal load at 20 per cent slip as a performance indicator, there is a reasonable correlation between the predictions and experimental data. This indicates that the NWVPM has the potential as an engineering tool for evaluating wheel candidates for a future generation of extra-terrestrial vehicles, provided that appropriate input data are available.

Wong, J. Y.; Asnani, V. M.

2008-01-01

350

Merging of aircraft vortex trails - Similarities to magnetic field merging  

NASA Technical Reports Server (NTRS)

This paper discusses the phenomenological and formal similarities between the merging of aircraft vortex trails and the merging of magnetic field lines in a plasma. High-resolution photographs are shown of smoke trails from the wing tips of an airplane. These photographs show that the two vortex trails merge together downstream of the aircraft in a way similar to the merging of oppositely directed magnetic field lines in a plasma. Although there are some differences, this correspondence is apparently related to the fact that the vorticity equation in a fluid has the same mathematical form as the magnetic field equation in an MHD plasma. In both cases the merging proceeds at a rate considerably faster than would be predicted from classical estimates of the viscosity and resistivity. The enhanced merging rate in the fluid case appears to result from turbulence that increases the diffusion rate in the merging region.

Gurnett, Donald A.

1989-01-01

351

BITC Sensitizes Pancreatic Adenocarcinomas to TRAIL-induced Apoptosis.  

PubMed

Pancreatic adenocarcinoma is an aggressive cancer with a greater than 95% mortality rate and short survival after diagnosis. Chemotherapeutic resistance hinders successful treatment. This resistance is often associated with mutations in codon 12 of the K-Ras gene (K-Ras 12), which is present in over 90% of all pancreatic adenocarcinomas. Codon 12 mutations maintain Ras in a constitutively active state leading to continuous cellular proliferation. Our study determined if TRAIL resistance in pancreatic adenocarcinomas with K-Ras 12 mutations could be overcome by first sensitizing the cells with Benzyl isothiocyanate (BITC). BITC is a component of cruciferous vegetables and a cell cycle inhibitor. BxPC3, MiaPaCa2 and Panc-1 human pancreatic adenocarcinoma cell lines were examined for TRAIL resistance. Our studies show BITC induced TRAIL sensitization by dual activation of both the extrinsic and intrinsic apoptotic pathways. PMID:20559452

Wicker, Christina A; Sahu, Ravi P; Kulkarni-Datar, Kashmira; Srivastava, Sanjay K; Brown, Thomas L

2010-01-20

352

Effects of meteoroid fragmentation on radar observations of meteor trails  

NASA Astrophysics Data System (ADS)

Radar reflections from meteor trails often differ from the predictions of simple models. There is general consensus that these differences are probably the result of fragmentation of the meteoroid. Several examples taken from different types of meteor radar observations are considered in order to test the validity of the fragmentation hypothesis. The absence of the expected Fresnel oscillations in many observations of transverse scatter from meteor trails is readily explained by assuming a number of ablating fragments spread out along the trails. Observations of amplitude fluctuations in head echoes from "down-the-beam" meteoroids are explained by gross fragmentation of a meteoroid into two or more pieces. Another down-the-beam event is modeled by simulation of the differential retardation of two fragments of different mass, giving reasonable agreement between the observed and predicted radar signals.

Elford, W. Graham; Campbell, L.

2001-11-01

353

Trailing Edge Noise Prediction Based on a New Acoustic Formulation  

NASA Technical Reports Server (NTRS)

A new analytic result in acoustics called 'Formulation 1B,' proposed by Farassat, is used to compute broadband trailing edge noise from an unsteady surface pressure distribution on a thin airfoil in the time domain. This formulation is a new solution of the Ffowcs Williams-Hawkings equation with the loading source term, and has been shown in previous research to provide time domain predictions of broadband noise that are in excellent agreement with experiment. Furthermore, this formulation lends itself readily to rotating reference frames and statistical analysis of broadband trailing edge noise. Formulation 1B is used to calculate the far field noise radiated from the trailing edge of a NACA 0012 airfoil in low Mach number flows, using both analytical and experimental data on the airfoil surface. The results are compared to analytical results and experimental measurements that are available in the literature. Good agreement between predictions and measurements is obtained.

Casper, J.; Farassat, F.

2002-01-01

354

Application of Passive Porous Treatment to Slat Trailing Edge Noise  

NASA Technical Reports Server (NTRS)

Porous trailing-edge treatment is investigated as a passive means for slat noise reduction by using time-accurate simulations based on Reynolds-averaged Navier-Stokes equations. For the model scale high-lift configuration used during previous experiments in the Low-Turbulence Pressure Tunnel at NASA Langley Research Center, application of the proposed treatment over a minute fraction of the slat surface area is shown to mitigate the noise impact of the trailing edge, with no measurable aerodynamic penalty. Assessment of the pressure fluctuations in the vicinity of the treated edge indicates a potential noise reduction in excess of 20 dB. The primary mechanism underlying this reduction is related to the reduced strength of Strouhal shedding from the finite thickness trailing edge. A secondary effect of the treatment involves an upward shift in the Strouhal-shedding frequency to a frequency band of reduced auditory sensitivity in a full-scale application.

Khorrami, Mehdi R.; Choudhari, Meelan M.

2003-01-01

355

A class of airfoils having finite trailing edge pressure gradients  

NASA Technical Reports Server (NTRS)

Some new developments relevant to the design of single-element airfoils using potential flow methods are presented. In particular, the ramifications of the unbounded trailing edge pressure gradients generally present in the potential flow solution for 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 for the design of low-speed airfoils is discussed, and designs generated using the modified scheme are presented for consideration. A detailed viscous analysis of one of these airfoils demonstrates a significant reduction in the strong inviscid-viscid interactions generally present near the trailing edge. These reductions offer the possibility of improved airfoil performance, as well as the possibility of improved accuracy in the methods of airfoil design and analysis.

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

1985-01-01

356

Robotic vehicle  

SciTech Connect

A robotic vehicle for travel through a conduit. The robotic vehicle includes forward and rear housings each having a hub portion, and each being provided with surface engaging mechanisms for selectively engaging the walls of the conduit such that the housings can be selectively held in stationary positions within the conduit. The surface engaging mechanisms of each housing includes a plurality of extendable appendages, each of which is radially extendable relative to the operatively associated hub portion between a retracted position and a radially extended position. The robotic vehicle also includes at least three selectively extendable members extending between the forward and rear housings, for selectively changing the distance between the forward and rear housings to effect movement of the robotic vehicle.

Box, W. Donald (Oak Ridge, TN)

1997-01-01

357

Robotic vehicle  

SciTech Connect

A robotic vehicle for travel through a conduit. The robotic vehicle includes forward and rear housings each having a hub portion, and each being provided with surface engaging mechanisms for selectively engaging the walls of the conduit such that the housings can be selectively held in stationary positions within the conduit. The surface engaging mechanisms of each housing includes a plurality of extendable appendages, each of which is radially extendable relative to the operatively associated hub portion between a retracted position and a radially extended position. The robotic vehicle also includes at least three selectively extendable members extending between the forward and rear housings, for selectively changing the distance between the forward and rear housings to effect movement of the robotic vehicle.

Box, W. Donald (Oak Ridge, TN)

1998-01-01

358

Robotic vehicle  

DOEpatents

A robotic vehicle is described for travel through a conduit. The robotic vehicle includes forward and rear housings each having a hub portion, and each being provided with surface engaging mechanisms for selectively engaging the walls of the conduit such that the housings can be selectively held in stationary positions within the conduit. The surface engaging mechanisms of each housing includes a plurality of extendable appendages, each of which is radially extendable relative to the operatively associated hub portion between a retracted position and a radially extended position. The robotic vehicle also includes at least three selectively extendable members extending between the forward and rear housings, for selectively changing the distance between the forward and rear housings to effect movement of the robotic vehicle. 20 figs.

Box, W.D.

1997-02-11

359

Robotic vehicle  

DOEpatents

A robotic vehicle is described for travel through a conduit. The robotic vehicle includes forward and rear housings each having a hub portion, and each being provided with surface engaging mechanisms for selectively engaging the walls of the conduit such that the housings can be selectively held in stationary positions within the conduit. The surface engaging mechanisms of each housing includes a plurality of extendible appendages, each of which is radially extendible relative to the operatively associated hub portion between a retracted position and a radially extended position. The robotic vehicle also includes at least three selectively extendible members extending between the forward and rear housings, for selectively changing the distance between the forward and rear housings to effect movement of the robotic vehicle. 20 figs.

Box, W.D.

1998-08-11

360

Engineering a leucine zipper-TRAIL homotrimer with improved cytotoxicity in tumor cells  

PubMed Central

Successful cancer therapies aim to induce selective apoptosis in neoplastic cells. The current suboptimal efficiency and selectivity drugs have therapeutic limitations and induce concomitant side effects. Recently, novel cancer therapies based on the use of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) have emerged. TRAIL, a key component of the natural antitumor immune response, selectively kills many tumor cell types. Earlier studies with recombinant TRAIL, however, revealed its many shortcomings including a short half-life, off-target toxicity, and existence of TRAIL-resistant tumor cells. We improved the efficacy of recombinant TRAIL redesigning its structure and the expression and purification procedures. The result is a highly stable leucine zipper (LZ)-TRAIL chimera that is simple to produce and purify This chimera functions as a trimer in a manner that similar to natural TRAIL. The formulation of the recombinant LZ-TRAIL we have developed has displayed high specific activity in both cell-based assays in vitro and animal tests in vivo. Our results have shown that the half-of LZ-TRAIL is improved and now exceeds 1 h in mice compared with a half-life of only minutes reported earlier for recombinant TRAIL. We have concluded that our LZ TRAIL construct will serve as a foundation for a new generation of fully human LZ-TRAIL proteins suitable use in preclinical and clinical studies and for effective combination therapies to overcome tumor resistance TRAIL. PMID:19509255

Rozanov, Dmitri V.; Savinov, Alexei Y.; Golubkov, Vladislav S.; Rozanova, Olga L.; Postnova, Tatiana I.; Sergienko, Eduard A.; Vasile, Stefan; Aleshin, Alexander E.; Rega, Michele F.; Pellecchia, Maurizio; Strongin, Alex Y.

2009-01-01

361

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

Code of Federal Regulations, 2010 CFR

... Driving, trailing, and engine truck axles. 230.98...DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Steam Locomotives and Tenders ...Driving, trailing, and engine truck axles. (a)...

2010-10-01

362

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

Code of Federal Regulations, 2012 CFR

... Driving, trailing, and engine truck axles. 230.98...DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Steam Locomotives and Tenders ...Driving, trailing, and engine truck axles. (a)...

2012-10-01

363

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

Code of Federal Regulations, 2014 CFR

... Driving, trailing, and engine truck axles. 230.98...DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Steam Locomotives and Tenders ...Driving, trailing, and engine truck axles. (a)...

2014-10-01

364

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

Code of Federal Regulations, 2011 CFR

... Driving, trailing, and engine truck axles. 230.98...DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Steam Locomotives and Tenders ...Driving, trailing, and engine truck axles. (a)...

2011-10-01

365

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

Code of Federal Regulations, 2013 CFR

... Driving, trailing, and engine truck axles. 230.98...DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Steam Locomotives and Tenders ...Driving, trailing, and engine truck axles. (a)...

2013-10-01

366

The influence of use, environmental and managerial factors on the width of recreational trails.  

PubMed

This paper evaluates the relative influences of use, managerial and environmental factors on trail width, from a survey of all formal trails in Acadia National Park, Maine, USA. A Trimble GPS was used to navigate to and collect data at sample points spaced at a 152.4 m (500 ft) interval across all National Park Service trails on Mount Desert Island. Regression analyses focus on increasing understanding of factors that influence the width of formal hiking trails. ANOVA analyses demonstrate differences in trail width based on trail surface type (class), and the presence or absence of trail borders. A novel approach of comparing intended widths to actual widths enabled us to look specifically at the avoidable and undesirable impacts associated with having a trail that is wider than intended. PMID:20538405

Wimpey, Jeremy F; Marion, Jeffrey L

2010-10-01

367

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

Code of Federal Regulations, 2010 CFR

...1 2010-07-01 2010-07-01 false High-voltage trailing cables; minimum design requirements...WORK AREAS OF UNDERGROUND COAL MINES Surface High-Voltage Distribution § 77.804 High-voltage trailing cables; minimum design...

2010-07-01

368

Compartmentalization of TNF-related apoptosis-inducing ligand (TRAIL) death receptor functions: emerging role of nuclear TRAIL-R2.  

PubMed

Localized in the plasma membrane, death domain-containing TNF-related apoptosis-inducing ligand (TRAIL) receptors, TRAIL-R1 and TRAIL-R2, induce apoptosis and non-apoptotic signaling when crosslinked by the ligand TRAIL or by agonistic receptor-specific antibodies. Recently, an increasing body of evidence has accumulated that TRAIL receptors are additionally found in noncanonical intracellular locations in a wide range of cell types, preferentially cancer cells. Thus, besides their canonical locations in the plasma membrane and in intracellular membranes of the secretory pathway as well as endosomes and lysosomes, TRAIL receptors may also exist in autophagosomes, in nonmembraneous cytosolic compartment as well as in the nucleus. Such intracellular locations have been mainly regarded as hide-outs for these receptors representing a strategy for cancer cells to resist TRAIL-mediated apoptosis. Recently, a novel function of intracellular TRAIL-R2 has been revealed. When present in the nuclei of tumor cells, TRAIL-R2 inhibits the processing of the primary let-7 miRNA (pri-let-7) via interaction with accessory proteins of the Microprocessor complex. The nuclear TRAIL-R2-driven decrease in mature let-7 enhances the malignancy of cancer cells. This finding represents a new example of nuclear activity of typically plasma membrane-located cytokine and growth factor receptors. Furthermore, this extends the list of nucleic acid targets of the cell surface receptors by pri-miRNA in addition to DNA and mRNA. Here we review the diverse functions of TRAIL-R2 depending on its intracellular localization and we particularly discuss the nuclear TRAIL-R2 (nTRAIL-R2) function in the context of known nuclear activities of other normally plasma membrane-localized receptors. PMID:25165876

Bertsch, U; Röder, C; Kalthoff, H; Trauzold, A

2014-01-01

369

The promise of TRAIL—potential and risks of a novel anticancer therapy  

Microsoft Academic Search

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promising new anticancer biotherapeutic. As shown by\\u000a many preclinical studies, TRAIL efficiently induces apoptosis in numerous tumor cell lines but not in the majority of normal\\u000a cells. However, an increasing number of publications report on a predominance of TRAIL resistance in primary human tumor cells,\\u000a which require sensitization for TRAIL-induced apoptosis. Sensitization

Ronald Koschny; Henning Walczak; Tom M. Ganten

2007-01-01

370

Functional solubilization of aggregation-prone TRAIL protein facilitated by coexpressing with protein isoaspartate methyltranferase  

Microsoft Academic Search

TRAIL was a tumor-specific protein in development as a novel anticancer therapeutic agent. Generally, when expressed in recombinant Escherichia\\u000a coli, TRAIL protein was prone to form inclusion bodies. In this study, coexpression of human TRAIL protein and protein isoaspartate methyltranferase (PIMT) from E. coli on plasmid pBV–TRAIL–PCM in E. coli C600 was investigated to overcome the difficulties in soluble expression.

Hu Zhu; Ruo-Jun Pan; Tian-Wen Wang; Ya-Ling Shen; Dong-Zhi Wei

2006-01-01

371

Increased Expression and a Potential Anti-Inflammatory Role of TRAIL in Atopic Dermatitis  

Microsoft Academic Search

The tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) induces apoptosis of many transformed but also of non-transformed cells. In addition, TRAIL receptor activation has been reported to activate non-apoptotic signaling pathways. Here, we report an increased expression of TRAIL in peripheral blood T cells and monocytes from patients with atopic dermatitis (AD) compared with control individuals. High TRAIL expression was also

Ekatherina Vassina; Martin Leverkus; Shida Yousefi; Lasse R. Braathen; Hans-Uwe Simon; Dagmar Simon

2005-01-01

372

Chemical cues used by prairie rattlesnakes (Crotalus viridis) to follow trails of rodent prey.  

PubMed

Each of 10 prairie rattlesnakes (Crotalus viridis) was exposed to three types of trails after striking rodent prey (Mus musculus). One trail was made with mouse urine, another was made with tap water, and the third consisted of materials from mouse integument. The snakes exhibited trailing behavior only when integumentary trails were available. It was concluded that prairie rattlesnakes do not utilize urinary cues; instead they attend to materials associated with rodent skin and fur. PMID:24264897

Chiszar, D; Melcer, T; Lee, R; Radcliffe, C W; Duvall, D

1990-01-01

373

Retrofiting survivability of military vehicles  

SciTech Connect

In Iraq the terrain was such that vehicles could be distributed horizontally, which reduced the effectiveness of mines. In the mountainous terrain of Pakistan and Afghanistan vehicles are forced to use the few, passable roads, which are dirt and easily seeded with plentiful, cheap, intelligent mines. It is desirable to reduce the losses to such mines, preferably by retrofit means that do not greatly increase weight or cost or reduce maneuverability. V-bottom vehicles - A known approach to reducing vulnerability is the Buffalo, a large vehicle developed by South Africa to address mine warfare. It has large tires, high axles, and a reinforced, v-shaped bottom that deflects the blast from explosions below. It is developed and tested in combat, but is expensive and has reduced off-road mobility. The domestic MRAP has similar cost and mobility issue. The addition of v-shaped blast deflectors to vehicles such as Humvees could act much as the deflector on a Buffalo, but a Humvee is closer to the ground, so the explosive's expansion would be reduced. The deflector would also reduce a Humvee's clearance for rough terrain, and a deflector of adequate thickness to address the blast by itself could further increase cost and reduce mobility. Reactive armor is developed and has proven effective against shaped and explosive charges from side or top attack. It detects their approach, detonates, and defeats them by interfering with jet formation. If the threat was a shaped charge from below, they would be a logical choice. But the bulk of the damage to Humvees appears to be from the blast from high explosive mines for which the colliding shock from reactive armor could increase that from the explosive. Porous materials such as sand can strongly attenuate the kinetic energy and pressure of a strong shock. Figure 1 shows the kinetic energy (KE), momentum (Mu), velocity (u), and mass (M) of a spherically expanding shock as functions of radius for a material with a porosity of 0.5. Over the range from 0.5 to 4.5 cm the shock KE is attenuated by a factor of {approx}70, while its momentum is changed little. The shock and particle velocity falls by a factor of 200 while the mass increases by a factor of 730. In the limit of very porous media u {approx} 1/M, so KE {approx} 1/M, which falls by a factor of {approx}600, while momentum Mu does not change at all. Figure 2 shows the KE, Mu, u, and M for a material with a porosity of 1.05, for which the KE changes little. In the limit of media of very low porosity, u {approx} 1/{radical}M, so KE is constant while Mu {approx} {radical}M, which increases by a factor of 15. Thus, if the goal is to reduce the peak pressure from strong explosions below, very porous materials, which strongly reduce pressure but do not increase momentum, are preferred to non-porous materials, which amplify momentum but do not decrease pressure. These predictions are in qualitative accord with the results of experiments at Los Alamos in which projectiles from high velocity, large caliber cannons were stopped by one to two sandbags. The studies were performed primarily to determine the effectiveness of sand in stopping fragments of various sizes, but could be extended to study sand's effectiveness in attenuating blast pressure. It would also be useful to test the above predictions on the effectiveness of media with higher porosity. Water barriers have been discussed but not deployed in previous retrofit survivability studies for overseas embassies. They would detect the flash from the mine detonation below, trigger a thin layer of explosive above a layer of water, and drive water droplets into the approaching blast wave. The blast loses energy in evaporating the droplets and loses momentum in slowing them. Under favorable conditions that could attenuate the pressure in the blast enough to prevent the penetration or disruption of the vehicle. However, such barriers would depend on prompt and reliable detonation detection and water droplet dispersal, which have not been tested. There is a large literature on the theoretical effec

Canavan, Gregory H [Los Alamos National Laboratory

2009-01-01

374

Autonomous vehicles  

SciTech Connect

There are various kinds of autonomous vehicles (AV`s) which can operate with varying levels of autonomy. This paper is concerned with underwater, ground, and aerial vehicles operating in a fully autonomous (nonteleoperated) mode. Further, this paper deals with AV`s as a special kind of device, rather than full-scale manned vehicles operating unmanned. The distinction is one in which the AV is likely to be designed for autonomous operation rather than being adapted for it as would be the case for manned vehicles. The authors provide a survey of the technological progress that has been made in AV`s, the current research issues and approaches that are continuing that progress, and the applications which motivate this work. It should be noted that issues of control are pervasive regardless of the kind of AV being considered, but that there are special considerations in the design and operation of AV`s depending on whether the focus is on vehicles underwater, on the ground, or in the air. The authors have separated the discussion into sections treating each of these categories.

Meyrowitz, A.L. [Navy Center for Applied Research in Artificial Intelligence, Washington, DC (United States)] [Navy Center for Applied Research in Artificial Intelligence, Washington, DC (United States); Blidberg, D.R. [Autonomous Undersea Systems Inst., Lee, NH (United States)] [Autonomous Undersea Systems Inst., Lee, NH (United States); Michelson, R.C. [Georgia Tech Research Inst., Smyrna, GA (United States)] [Georgia Tech Research Inst., Smyrna, GA (United States); [International Association for Unmanned Vehicle Systems, Smyrna, GA (United States)

1996-08-01

375

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

USGS Publications Warehouse

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.

Wimpey, Jeremy; Marion, Jeffrey L.

2011-01-01

376

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

PubMed

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. PMID:21129844

Wimpey, Jeremy; Marion, Jeffrey L

2011-03-01

377

UNIVERSITY OF TORONTO SCARBOROUGH 1265 Military Trail, Toronto, Ontario M1C 1A4  

E-print Network

UNIVERSITY OF TORONTO SCARBOROUGH 1265 Military Trail, Toronto, Ontario M1C 1A4 Academic English @ UTSC #12;UNIVERSITY OF TORONTO SCARBOROUGH 1265 Military Trail, Toronto, Ontario M1C 1A4 A new way OF TORONTO SCARBOROUGH 1265 Military Trail, Toronto, Ontario M1C 1A4 Admissibility Students do not need

Boonstra, Rudy

378

THE DESIGN OF SELF-GUILDING, INTERPRETATIVE, NATURE TRAILS ACCESSIBLE TO THE DISABLED  

Microsoft Academic Search

Nature trails which are accessible to the physically handicapped are an important means of providing opportunities for valuable outdoor experiences. To heighten these experiences and foster an appreciation for nature, accessible trails should make use of interpretative techniques which lead to a first-hand involvement with the natural environment. Two self-guilding, interpretative, woodland nature trails have been designed and constructed at

Alan P Watson

1982-01-01

379

2D numerical comparison of trailing edge flaps -UpWind WP1B3  

E-print Network

of the model the dynamic behavior of the trailing edge (TE) separation is likewise modeled using an assumed2D numerical comparison of trailing edge flaps - UpWind WP1B3 Thomas Buhl1 , Peter B. Andersen1, Peter B. Andersen and Thanasis K. Barlas Title: 2D numerical comparison of trailing edge flaps - Up

380

Alpine Vegetation Restoration of Social Trails on Colorado's 14,000Foot Peaks  

Microsoft Academic Search

Heavy and rapidly increasing recreation on Colorado's high peaks requires restoration of closed social trails. We tested several restoration techniques on three peaks at elevations of 3660 to 3900 m. Species in turf blocks cut from newly constructed trails survived extremely well 3 yr after transplanting to closed trails. Most species did not decrease in cover although the sums of

James J. Ebersole; Robin F. Bay; David B. Conlin

2004-01-01

381

Comprehensive Trail Making Test Performance in Children and Adolescents with Traumatic Brain Injury  

ERIC Educational Resources Information Center

The sensitivity of the Trail Making Test to brain damage has been well-established over many years, making it one of the most commonly used tests in clinical neuropsychological evaluations. The current study examined the validity of scores from a newer version of the Trail Making Test, the Comprehensive Trail Making Test (CTMT), in children and…

Allen, Daniel N.; Thaler, Nicholas S.; Ringdahl, Erik N.; Barney, Sally J.; Mayfield, Joan

2012-01-01

382

Long lasting heat shock stimulation of TRAIL-induced apoptosis in transformed T lymphocytes  

Microsoft Academic Search

We report that a mild heat shock, that did not impair cell growth, stimulated TNF-related apoptosis inducing ligand (TRAIL)-mediated apoptosis of leukemic T lymphocytes and promyelocytic cells, but not normal human T lymphocytes. The death stimulation was maximal when the heat shock was performed at the beginning of the exposure to TRAIL. However, enhanced apoptosis was still observed when TRAIL

Maryline Moulin; André-Patrick Arrigo

2006-01-01

383

The influence of use, environmental and managerial factors on the width of recreational trails  

Microsoft Academic Search

This paper evaluates the relative influences of use, managerial and environmental factors on trail width, from a survey of all formal trails in Acadia National Park, Maine, USA. A Trimble GPS was used to navigate to and collect data at sample points spaced at a 152.4 m (500 ft) interval across all National Park Service trails on Mount Desert Island. Regression analyses

Jeremy F. Wimpey; Jeffrey L. Marion

2010-01-01

384

The Use of Variants of the Trail Making Test in Serial Assessment: A Construct Validity Study  

ERIC Educational Resources Information Center

The construct validity of three variants of the Trail Making Test was investigated using 162 undergraduate psychology students. During a 3-week period, the Trail Making Test of the Delis-Kaplan Executive Function System, Comprehensive Trail Making Test, and Connections Task were administered in six possible orders. Using confirmatory factor…

Atkinson, Thomas M.; Ryan, Jeanne P.

2008-01-01

385

Reduction of the shock wave intensity by modifying the transonic blade trailing edge  

NASA Technical Reports Server (NTRS)

It is shown that the shock wave intensity can be decreased by using modified trailing edge configurations to reduce or even completely compensate for the effect of the finite thickness of the trailing edge. A theoretical analysis is presented together with numerical results for two supersonic streams flowing off the trailing edge at different velocities. The analysis is based on an ideal gas model.

Doerffer, P.

1983-01-01

386

Dependence of radar signal strength on frequency and aspect angle of nonspecular meteor trails  

NASA Astrophysics Data System (ADS)

When a meteoroid penetrates Earth's atmosphere, it forms a high-density ionized plasma column immersed in the ionosphere between approximately 70 and 140 km altitude. High-power, large-aperture (HPLA) radars detect nonspecular trails when VHF or UHF radio waves reflect off structures in a turbulent meteor trail. These trails persist from a few milliseconds to many minutes and the return from these trails is referred to as nonspecular trails or range-spread trail echoes. In this paper, we present analysis of nonspecular trails detected with ALTAIR, which is an HPLA radar operating simultaneously at 160 MHz and 422 MHz on the Kwajalein Atoll. First, we investigate the aspect sensitivity of nonspecular trails and show that as the angle between the radar beam and the background magnetic field increases, the signal strength falls off 3 to 4 dB per degree at 160 MHz. For ALTAIR, this means that the aspect angle must be within approximately 12 degrees in order to detect nonspecular trails using the chosen waveforms. Second, we compare and contrast the meteoroids that form nonspecular trails and find that the meteoroid energy causes much of the variability in the nonspecular trail's signal-to-noise ratio (SNR) for a given aspect angle. In addition, we show two range-resolved fragmentation events that also affect the SNR. Finally, we determine the dependence of SNR on wavelength using two wavelengths and show that the maximum nonspecular trail SNR scales as approximately ?6, with a variation that depends upon altitude.

Close, S.; Hamlin, T.; Oppenheim, M.; Cox, L.; Colestock, P.

2008-06-01

387

Targeting AML through DR4 with a novel variant of rhTRAIL  

PubMed Central

Despite progress in the treatment of acute myelogenous leukaemia (AML) the outcome often remains poor. Tumour necrosis factor related apoptosis-inducing ligand (TRAIL) is a promising therapeutic agent in many different types of tumours, but AML cells are relatively insensitive to TRAIL-induced apoptosis. Here we show that TRAIL-induced apoptosis in AML cells is predominantly mediated by death receptor 4 (DR4) and not DR5. Therefore, we constructed a variant of TRAIL (rhTRAIL-C3) that is a strong inducer of DR4-mediated apoptosis. TRAIL-C3 demonstrated much stronger pro-apoptotic activity than wild-type (WT) TRAIL in a panel of AML cell lines as well as in primary AML blasts. The higher pro-apoptotic potential was further enhanced when the TRAIL mutant was used in combination with BMS-345541, a selective inhibitor of inhibitor-?B kinases. It illustrates that combination of this TRAIL variant with chemotherapeutics or other targeted agents can kill AML with high efficacy. This may represent a major advantage over the currently used therapies that have serious toxic side effects. The high efficacy of rhTRAIL-C3 containing therapies may enable the use of lower drug doses to reduce the toxic side effects and improve patient outcome. Our findings suggest that the rational design of TRAIL variants that target DR4 potentiate the death-inducing activity of TRAIL and offer a novel therapeutic strategy for the treatment of AML. PMID:21070598

Szegezdi, Eva; Reis, Carlos R; van der Sloot, Almer M; Natoni, Alessandro; O’Reilly, Aoife; Reeve, Janice; Cool, Robbert H; O’Dwyer, Michael; Knapper, Steven; Serrano, Luis; Quax, Wim J; Samali, Afshin

2011-01-01

388

Nonspecular meteor trail altitude distributions and durations observed by a 50 MHz highpower radar  

E-print Network

Nonspecular meteor trail altitude distributions and durations observed by a 50 MHz highpower radar observe nonspecular meteor trail echoes that result from plasma turbulence driven by the intense pressure power. An improved knowledge of nonspecular trails will allow researchers to better understand meteor

Oppenheim, Meers

389

Interpretation of non-specular radar meteor trails Lars P. Dyrud,1  

E-print Network

Interpretation of non-specular radar meteor trails Lars P. Dyrud,1 Meers M. Oppenheim,1 Sigrid. [1] Radar data of non-specular meteor trails shows two clear and consistent features: (1) non­specular meteor trails are observed from a narrower altitude range than are head echoes and (2) an approximately

Oppenheim, Meers

390

Introduction to Special Issue Trails and Greenways: Opportunities for Planners, Managers, and Scholars  

Microsoft Academic Search

This paper presents an overview of trails and greenways as a field of practice and study. We start with definitions of both trails and greenways and consider some of the ways that they are separate but related. Historically, trails and greenways have been important parts of human activity through exploration and settlement. A brief overview of this history is provided

Roger L. Moore; C. Scott Shafer

391

Maintenance of Recreational Trails Presented by: SRF Consulting Group, Inc.  

E-print Network

'-0" 2'-3' Shoulder Clearance to Signs #12;Presentation Outline · Operational Maintenance Activities · Spring/Fall · Winter #12;Operational Maintenance Activities Trail Maintenance Schedule #12;Operational Activities Vegetation Maintenance · Rain garden maintenance · Maintain sightlines (intersections, signs

Minnesota, University of

392

The Appalachian Trail: Guidelines for Preservation, Revised May 1977.  

ERIC Educational Resources Information Center

With increasing developmental pressure being asserted on land resources, there is a need for identifying unique areas that, once destroyed, may never be recouped. Many of the areas suffering from developmental encroachment are located on or along the Appalachian Trail, which is a continuous footpath about 2,000 miles long that follows the…

Pennsylvania State Univ., University Park. Dept. of Landscape Architecture.

393

Dust trailing from the top chord, the bridge falls toward ...  

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

Dust trailing from the top chord, the bridge falls toward the river, as the southwest end (right) falls first. View southeast from confluence of Trinity and South Fork Trinity Rivers - South Fork Trinity River Bridge, State Highway 299 spanning South Fork Trinity River, Salyer, Trinity County, CA

394

14. VIEW FROM TUNDRA CURVES (ON TRAIL RIDGE ROAD) SHOWING ...  

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

14. VIEW FROM TUNDRA CURVES (ON TRAIL RIDGE ROAD) SHOWING FALL RIVER ROAD RISING FROM BENEATH CHAPIN PASS (AT EXTREME RIGHT) TO FALL RIVER PASS (FAR LEFT). - Fall River Road, Between Estes Park & Fall River Pass, Estes Park, Larimer County, CO

395

Social itinerary recommendation from user-generated digital trails  

Microsoft Academic Search

Planning travel to unfamiliar regions is a difficult task for novice travelers. The burden can be eased if the resident of the area offers to help. In this paper, we propose a social itinerary recommendation by learning from multiple user-generated digital trails, such as GPS trajectories of residents and travel experts. In order to recommend satisfying itinerary to users, we

Hyoseok Yoon; Yu Zheng; Xing Xie; Woontack Woo

2012-01-01

396

Dispersion of meteor trails in the geomagnetic field  

NASA Astrophysics Data System (ADS)

A meteor trail is modeled by a long column of weakly ionized plasma, whose dispersion is controlled by the geomagnetic field and the requirement to maintain effective space charge neutrality. First we consider scattering of a radar signal from an underdense trail and derive an expression for the amplitude of the backscattered signal as a function of time. Then, starting from the basic momentum balance equations for electrons and ions in a partially ionized plasma, we require divergences of ion and electron fluxes to be equal, plus assume equality of the flux components along the magnetic field direction. The analysis is really applicable to a whole range of plasma problems, although we focus upon meteor trails for now. It is found that charged particle densities satisfy a diffusion equation and we obtain an expression for the ambipolar diffusion tensor and expressions for the ambipolar electric field, valid for arbitrary relative orientations of the magnetic field and meteor trail axis. Results are somewhat different from previous analyses in the meteor literature.

Robson, R. E.

2001-02-01

397

PACKING DIGRAPHS WITH DIRECTED CLOSED TRAILS PAUL BALISTER  

E-print Network

PACKING DIGRAPHS WITH DIRECTED CLOSED TRAILS PAUL BALISTER Abstract. It has been shown [Balister that sufficiently dense Eulerian digraphs can be decomposed in a similar manner, and we prove corresponding results will be finite simple graphs or digraphs (without loops or multiple edges). Write V (G) for the vertex set and E

Balister, Paul

398

Two Bridges Formation on the Navajo Loop Trail  

USGS Multimedia Gallery

Views along the Navajo Loop Trail in Bryce Canyon National Park. Bryce Canyon is a unique sandstone formation in southern Utah. It is home to a large number of hoodoos, which are oddly shaped pillars of rock that formed due to different erosion rates for the dolomite that caps them and the sandston...

399

The Dust Trail of Comet Churyumov-Gerasimenko Near Aphelion  

NASA Astrophysics Data System (ADS)

We present optical and infrared (24 micron) images of the dust trail of comet 67P/Churyumov-Gerasimenko near aphelion, obtained with the Wide Field Imager at the MPG/ESO 2.2m telescope in La Silla in 2004 and with NASA's Spitzer Space Telescope in 2005 and 2006, respectively. Based on these images, we constrain the size distribution and material properties of mm-sized dust grains emitted from the comet. These particles remain close to the comet's orbit because of weak radiation pressure and low emission speeds, thereby forming the comet's dust trail. We evaluate the size distribution of the trail particles by fitting simulated images to the measured intensities. As far as possible, the parameters of the underlying model are derived from the observed emission history of Churyumov-Gerasimenko. The size distribution is a crucial parameter for estimating the number density of large particles in the neighbourhood of the comet nucleus and for the safety of ESA's Rosetta spacecraft which will pass through the trail region on its approach to Churyumov-Gerasimenko in 2013. This research is supported by NASA and the Studienstiftung des deutschen Volkes

Gruen, Eberhard; Agarwal, J.; Mueller, M.; Boehnhardt, H.; Reach, W. T.; Sykes, M. V.; Lien, D. J.

2006-09-01

400

What Cognitive Abilities Are Involved in Trail-Making Performance?  

ERIC Educational Resources Information Center

The cognitive abilities involved in the Connections (Salthouse, et al., 2000) version of the trail making test were investigated by administering the test, along with a battery of cognitive tests and tests of complex span and updating conceptualizations of working memory, to a sample of over 3600 adults. The results indicate that this variant of…

Salthouse, Timothy A.

2011-01-01

401

Basic Sequence Analysis Techniques for Use with Audit Trail Data  

ERIC Educational Resources Information Center

Audit trail analysis can provide valuable insights to researchers and evaluators interested in comparing and contrasting designers' expectations of use and students' actual patterns of use of educational technology environments (ETEs). Sequence analysis techniques are particularly effective but have been neglected to some extent because of real…

Judd, Terry; Kennedy, Gregor

2008-01-01

402

VideoTrails: Representing and Visualizing Structure in Video Sequences  

E-print Network

- ters over time, we lay the groundwork for the complete analysis and representation of the video analysis, indexing, and retrieval of video sequences are important missing components in today's videoVideoTrails: Representing and Visualizing Structure in Video Sequences Vikrant Kobla, David

Faloutsos, Christos

403

Mining, Modeling, and Analyzing Real-Time Social Trails  

E-print Network

to Twitter or Facebook; the creation, sharing, and viewing of videos on websites like YouTube; and so on. While access to social trails could benefit many domains there is a significant research gap toward discovering, modeling, and leveraging these social...

Kamath, Krishna Y

2013-05-28

404

Administration and interpretation of the Trail Making Test  

Microsoft Academic Search

Measurement of cognitive functions is an increasingly important goal for clinicians and researchers. Many neuropsychological test batteries are comprehensive and require specialized training to administer and interpret. The Trail Making Test is an accessible neuropsychological instrument that provides the examiner with information on a wide range of cognitive skills and can be completed in 5–10 min. Its background, psychometric properties,

Christopher R Bowie; Philip D Harvey

2006-01-01

405

Trail Camera Installation to Monitor Erosion along Missouri River  

USGS Multimedia Gallery

A South Dakota School of Mines and Technology student working for the USGS South Dakota Water Science Center installed a trail camera at the Lodge site in the fall of 2013 to take time-lapse images of shoreline erosion along the Missouri River near the town of Lower Brule on the Lower Brule Res...

406

Trail Camera Installation to Monitor Erosion along Missouri River  

USGS Multimedia Gallery

A South Dakota School of Mines and Technology student working for the USGS South Dakota Water Science Center installed a trail camera in the fall of 2013 on a pole at the Playground site to take time-lapse images of shoreline erosion along the Missouri River near the town of Lower Brule on...

407

South Florida Natural Resources Center Runoff Under the Trail  

E-print Network

South Florida Natural Resources Center Runoff Under the Trail: An Historical Analysis of Flows Resources Branch South Florida Natural Resources Center Everglades National Park #12;South Florida Natural Resources Center #12;South Florida Natural Resources Center #12;South Florida Natural Resources Center #12

Sukop, Mike

408

Evolution of isolated turbulent trailing vortices Karthik Duraisamy1,a  

E-print Network

of physical and engineering interest such as tornadoes, air- plane trailing vortices, and swirling jets. Many that an infinite family of unstable center-modes exist for q 2.31. In the viscous case, unstable center-modes have been shown to exist5 at all swirl numbers. However, akin to the center- modes in the inviscid case

Alonso, Juan J.

409

Broadband trailing edge noise predictions in the time domain  

Microsoft Academic Search

A recently developed analytic result in acoustics, “Formulation 1B,” is used to compute broadband trailing edge noise from an unsteady surface pressure distribution on a thin airfoil in the time domain. This formulation is a new solution of the Ffowcs Williams–Hawkings equation with the loading source term, and has been shown in previous research to provide time domain predictions of

J. Casper; F. Farassat

2004-01-01

410

The Clam Trail: Blending Science Education, Public Art, and Tourism  

ERIC Educational Resources Information Center

The Barnegat Bay Shellfish Restoration's Clam Trail is an award-winning scavenger hunt that combines science education, public art, and tourism. This family adventure has participants seeking out giant painted fiberglass clams, upweller clam nurseries, and points of interest in search of science facts to record on their forms. Upon returning these…

Muscio, Cara; Flimlin, Gef; Bushnell, Rick

2011-01-01

411

In Search of the Ways of Knowing Trail  

NSDL National Science Digital Library

In this Flash animated adventure, learners explore the Ituri Forest and the village of Epulu in central Africa. Learners "travel" with four other kids and can use the Forest Factbook containing definitions and pronunciations to help them along the way. Through this interactive game, learners will solve problems, discover the rich biodiversity of the area, and learn the "secret" of the knowing trail.

2012-06-26

412

Geoscience exhibit displays `Trail of Time' By Nicole Staab Cassis  

E-print Network

and breadth of beauty and unequaled in inspirational power, the Grand Canyon is a natural masterpiece. Acting- line trail focuses on the Grand Canyon's vistas and rocks and aims to guide visitors toward a better, and Judy Bryan, chief of interpretation at Grand Canyon National Park, was the primary collaborator between

Rhoads, James

413

9. VIEW FROM MANY PARKS CURVE (ON TRAIL RIDGE ROAD) ...  

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

9. VIEW FROM MANY PARKS CURVE (ON TRAIL RIDGE ROAD) OF HORSESHOE PARK, SHOWING FALL RIVER ROAD FAINTLY AT LEFT AT BASE OF SHEEP MOUNTAIN AND CROSSING ALLUVIAL FAN FROM LAWN LAKE FLOOD. - Fall River Road, Between Estes Park & Fall River Pass, Estes Park, Larimer County, CO

414

Observations of persistent Leonid meteor trails 3. The ``Glowworm''  

E-print Network

Observations of persistent Leonid meteor trails 3. The ``Glowworm'' Jack D. Drummond,1 Brent W August 2002. [1] A spectacular, well-observed Leonid meteor of visual magnitude Ã?14.3 appeared on 17 s after the meteor and recorded a video with an intensified camera for even longer. From information

Chu, Xinzhao

415

Adaptive Neurocontrol of Simulated Rotor Vibrations Using Trailing Edge Flaps  

Microsoft Academic Search

Smart structure activated trailing edge flaps are capable of actively altering the aerodynamic loads on rotor blades. Coupled with a suitable feedback control law, such actuators could potentially be used to counter the vibrations induced by periodic aerodynamic loading on the blades, without the bandwidth constraints and with a potential of lower weight penalties incurred by servo actuation methods. This

Michael G. Spencer; Robert M. Sanner; Inderjit Chopra

1999-01-01

416

The Western Maryland Rail Trail passes high above the canal ...  

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

The Western Maryland Rail Trail passes high above the canal and behind the surviving remains of the Round Top cement works, milepost 120, looking northwest. - Western Maryland Railway, Cumberland Extension, Pearre to North Branch, from WM milepost 125 to 160, Pearre, Washington County, MD

417

Hybrid Vehicles  

NSDL National Science Digital Library

The first site takes you to the very informative essay at Motor Trend's site on its car of the year, the Toyota Prius (1). The next site is from the Union of Concerned Scientists. This great resource, called Clean Vehicles, offers all sorts of info about vehicles for the future (2). The Department of Energy's Hybrid Electric Vehicle Program page (3 ) offers lots of good information about the technology surrounding the cars as well as information on how you can get a tax break if you buy one. In fairness to both Honda (4 ) (Note: Honda also makes the Insight) and Toyota (5 ) these two sites take you to their webpages devoted to their two comparable hybrid cars, the Honda Civic Hybrid and the Toyota Prius. The last site takes you to a recent story on NPR about the future of hybrid technology and hybrid SUVs (6 )

418

A radio science perspective on long-duration meteor trails  

NASA Astrophysics Data System (ADS)

Nonclassical radar meteor echoes or range spread trail echoes (RSTEs), lasting from tens of seconds to over 15 min, have been a subject of considerable interest and speculation in the community ever since they were first observed in the 1940s. Using data collected from the Jicamarca Radio Observatory 50 MHz VHF radar in June 2006, we find that many properties of RSTEs can be explained largely from a radio science perspective. On a statistical basis, RSTEs of duration >15 s are observed exclusively from scatterers in the k $\\perp$ B (k = radar wave number; B = geomagnetic field) region apparently as the result of trail evolution parallel to B, forming approximately Fresnel-zone sized scattering regions thus narrowing the scattering pattern. This result implies that the initial irregularity structures in the meteor trail exhibit a wide scattering pattern that can be seen from anywhere in the radar beam given sufficient radar sensitivity but once the trail significantly elongates along B, it can be detected only from the k $\\perp$ B region of the radar. This conclusion has far-reaching implications to current interpretations of instability development in RSTEs as the location of the meteoroid trajectory relative to the narrow k $\\perp$ B region strongly determines observed RSTE properties such as onset time relative to the head echo and trail lifetime as functions of altitude. That is, a RSTE event viewed by two closely spaced identical radars would have different properties. Meteoroid size, energy, and fragmentation as well as radar properties such as frequency, beam pattern, and absolute sensitivity play obvious roles as well.

Malhotra, Akshay; Mathews, John D.; Urbina, Julio

2007-12-01

419

Mesenchymal Stem Cell delivery of TRAIL can eliminate Metastatic Cancer  

PubMed Central

Cancer is a leading cause of mortality throughout the world and new treatments are urgently needed. Recent studies suggest that bone marrow-derived mesenchymal stem cells (MSCs) home to and incorporate within tumor tissue. We hypothesised that MSCs engineered to produce and deliver TNF-related apoptosis-inducing ligand (TRAIL), a transmembrane protein which causes selective apoptosis of tumor cells, would home to and kill cancer cells in a lung metastatic cancer model. Human MSCs were transduced with TRAIL and the IRES-eGFP reporter gene, under the control of a tetracycline promoter using a lentiviral vector. Transduced and activated MSCs caused lung (A549), breast (MDAMB231), squamous (H357), and cervical (Hela) cancer cell apoptosis and death in co-culture experiments. Subcutaneous xenograft experiments confirmed directly delivered TRAIL-expressing MSCs were able to significantly reduce tumor growth (0.12 cm3 (0.04-0.21) vs 0.66 cm3 (0.21-1.11) (p<0.001)). We then found using a pulmonary metatastasis model, systemically delivered MSCs localised to lung metastases and the controlled local delivery of TRAIL completely cleared the metastatic disease in 38% of mice compared to 0% of controls (p<0.05). This is the first study to demonstrate a significant reduction in metastatic tumor burden with frequent eradication of metastases using inducible TRAIL-expressing MSCs. This has a wide potential therapeutic role, which includes the treatment of both primary tumors and their metastases, possibly as an adjuvant therapy in clearing micrometastatic disease following primary tumor resection. PMID:19435900

Loebinger, Michael R.; Eddaoudi, Ayad; Davies, Derek; Janes, Sam M.

2009-01-01

420

Human serum albumin-TRAIL conjugate for the treatment of rheumatoid arthritis.  

PubMed

Albumin conjugation is viewed as an effective means of protracting short in vivo lifespans of proteins and targeting rheumatoid arthritis (RA). In this study, we present a human serum albumin (HSA) conjugate linked with tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) via a bifunctional PEG derivative (HSA-TRAIL). Prepared HSA-TRAIL was found to have a larger molecular size (?240 kDa, 15.4 nm) than TRAIL (?66 kDa, 6.2 nm), and its bioactivity (apoptosis, cytotoxicity, and antiproliferation) was well preserved in Mia Paca-2 cells and mouse splenocytes. The enhanced therapeutic efficacy of HSA-TRAIL was demonstrated in collagen-induced arthritis (CIA) mice. The incidence and clinical scores, expressed as degree of erythema and swelling in HSA-TRAIL-treated mice, were remarkably lower than those of TRAIL-treated mice. The serum levels of pro-inflammatory cytokines IFN-?, TNF-?, IL-1?, and IL-2 in HSA-TRAIL-treated mice were significantly lower than those of TRAIL-treated mice. Furthermore, HSA-TRAIL accumulated in the hind paws of CIA mice, not in naïve TRAIL mice. Pharmacokinetic profiles of HSA-TRAIL were greatly improved in comparison to those of TRAIL (AUCinf: 844.1 ± 130.0 vs 36.0 ± 1.2 ng·h/mL; t1/2: 6.20 ± 0.72 vs 0.23 ± 0.01 h, respectively). The HSA-TRAIL conjugate, which presents clear advantages of targeting RA and long systemic circulation by HSA and unique anti-inflammatory efficacy by TRAIL, has potential as a novel treatment for rheumatoid arthritis. PMID:25387356

Byeon, Hyeong Jun; Min, Sun Young; Kim, Insoo; Lee, Eun Seong; Oh, Kyung Taek; Shin, Beom Soo; Lee, Kang Choon; Youn, Yu Seok

2014-12-17

421

Development, parameterization, and validation of a visco-plastic material model for sand with different  

E-print Network

as the assessment of the off-road (uneven-terrain) vehicle dynamics (including vehicle rollover stability, crew@ces.clemson.edu with the target structures/vehicles as well as of the off-road vehicle dynamics is still not mature. As discussed and is suitable for both mine-blast and off-road vehicle dynamics computational analyses. JMDA237 © IMechE 2009

Grujicic, Mica

422

Robotic vehicle  

DOEpatents

A robotic vehicle is described for travel through an enclosed or partially enclosed conduit or pipe including vertical and/or horizontal conduit or pipe. The robotic vehicle comprises forward and rear housings each provided with a surface engaging mechanism for selectively engaging the walls of the conduit through which the vehicle is travelling, whereby the housings are selectively held in a stationary position within the conduit. The vehicle also includes at least three selectively extendable members, each of which defines a cavity therein. The forward end portion of each extendable member is secured to the forward housing and the rear end portion of each housing is secured to the rear housing. Each of the extendable members is independently extendable from a retracted position to an extended position upon the injection of a gas under pressure into the cavity of the extendable member such that the distance between the forward housing and the rear housing can be selectively increased. Further, each of the extendable members is independently retractable from the extended position to the retracted position upon the application of a vacuum to the cavity of the extendable member such that the distance between the forward housing and the rear housing can be selectively decreased. 11 figures.

Box, W.D.

1994-03-15

423

Robotic vehicle  

DOEpatents

A robotic vehicle is described for travel through an enclosed or partially enclosed conduit or pipe including vertical and/or horizontal conduit or pipe. The robotic vehicle comprises forward and rear housings each provided with a surface engaging mechanism for selectively engaging the walls of the conduit through which the vehicle is travelling, whereby the housings are selectively held in a stationary position within the conduit. The vehicle also includes at least three selectively extendable members, each of which defines a cavity therein. The forward end portion of each extendable member is secured to the forward housing and the rear end portion of each housing is secured to the rear housing. Each of the extendable members is independently extendable from a retracted position to an extended position upon the injection of a gas under pressure into the cavity of the extendable member such that the distance between the forward housing and the rear housing can be selectively increased. Further, each of the extendable members is independently retractable from the extended position to the retracted position upon the application of a vacuum to the cavity of the extendable member such that the distance between the forward housing and the rear housing can be selectively decreased. 14 figs.

Box, W.D.

1996-03-12

424

Robotic vehicle  

DOEpatents

A robotic vehicle (10) for travel through an enclosed or partially enclosed conduit or pipe including vertical and/or horizontal conduit or pipe. The robotic vehicle (10) comprises forward and rear housings (32 and 12) each provided with a surface engaging mechanism for selectively engaging the walls of the conduit through which the vehicle is travelling, whereby the housings (32 and 12) are selectively held in a stationary position within the conduit. The vehicle (10) also includes at least three selectively extendable members (46), each of which defines a cavity (56) therein. The forward end portion (50) of each extendable member (46) is secured to the forward housing (32) and the rear end portion (48) of each housing is secured to the rear housing (12). Each of the extendable members (46) is independently extendable from a retracted position to an extended position upon the injection of a gas under pressure into the cavity (56) of the extendable member such that the distance between the forward housing (32 ) and the rear housing (12) can be selectively increased. Further, each of the extendable members (46) is independently retractable from the extended position to the retracted position upon the application of a vacuum to the cavity (56) of the extendable member (46) such that the distance between the forward housing (32) and the rear housing (12) can be selectively decreased.

Box, W. Donald (Oak Ridge, TN)

1996-01-01

425

Robotic vehicle  

DOEpatents

A robotic vehicle (10) for travel through an enclosed or partially enclosed conduit or pipe including vertical and/or horizontal conduit or pipe. The robotic vehicle (10) comprises forward and rear housings (32 and 12) each provided with a surface engaging mechanism for selectively engaging the walls of the conduit through which the vehicle is travelling, whereby the housings (32 and 12) are selectively held in a stationary position within the conduit. The vehicle (10) also includes at least three selectively extendable members (46), each of which defines a cavity (56) therein. The forward end portion (50) of each extendable member (46) is secured to the forward housing (32) and the rear end portion (48) of each housing is secured to the rear housing (12). Each of the extendable members (46) is independently extendable from a retracted position to an extended position upon the injection of a gas under pressure into the cavity (56) of the extendable member such that the distance between the forward housing (32 ) and the rear housing (12) can be selectively increased. Further, each of the extendable members (46) is independently retractable from the extended position to the retracted position upon the application of a vacuum to the cavity (56) of the extendable member (46) such that the distance between the forward housing (32) and the rear housing (12) can be selectively decreased.

Box, W. Donald (115 Newhaven Rd., Oak Ridge, TN 37830)

1994-01-01

426

Detection of Water Hazards for Autonomous Robotic Vehicles  

NASA Technical Reports Server (NTRS)

Four methods of detection of bodies of water are under development as means to enable autonomous robotic ground vehicles to avoid water hazards when traversing off-road terrain. The methods involve processing of digitized outputs of optoelectronic sensors aboard the vehicles. It is planned to implement these methods in hardware and software that would operate in conjunction with the hardware and software for navigation and for avoidance of solid terrain obstacles and hazards. The first method, intended for use during the day, is based on the observation that, under most off-road conditions, reflections of sky from water are easily discriminated from the adjacent terrain by their color and brightness, regardless of the weather and of the state of surface waves on the water. Accordingly, this method involves collection of color imagery by a video camera and processing of the image data by an algorithm that classifies each pixel as soil, water, or vegetation according to its color and brightness values (see figure). Among the issues that arise is the fact that in the presence of reflections of objects on the opposite shore, it is difficult to distinguish water by color and brightness alone. Another issue is that once a body of water has been identified by means of color and brightness, its boundary must be mapped for use in navigation. Techniques for addressing these issues are under investigation. The second method, which is not limited by time of day, is based on the observation that ladar returns from bodies of water are usually too weak to be detected. In this method, ladar scans of the terrain are analyzed for returns and the absence thereof. In appropriate regions, the presence of water can be inferred from the absence of returns. Under some conditions in which reflections from the bottom are detectable, ladar returns could, in principle, be used to determine depth. The third method involves the recognition of bodies of water as dark areas in short-wavelength infrared (SWIR) images. This method is based on the fact, well known among experts in remote sensing, that water bodies of any appreciable depth appear very dark in near-infrared, overhead imagery. Even under a thick layer of marine fog, SWIR illumination is present. Hence, this method may work even in the presence of clouds, though it is unlikely to work at night. Snow and ice also exhibit very strong absorption at wavelengths greater than about 1.4 m. Hence, the wavelength range of about 1.5 to 1.6 m might be useable in this method for recognizing water, snow, and ice. One notable drawback of this method is that useful look-ahead distance could be limited by surface reflections. The fourth method, intended for use at night, involves the contrast between water and terrain in thermal-infrared (medium-wavelength infrared) imagery. This method is based on the fact that at night, water is usually warmer than the adjacent terrain. Look-ahead distance could be limited in this method because, for reasons not yet fully understood, water appears to darken in the thermal infrared with increasing distance.

Matthes, Larry; Belluta, Paolo; McHenry, Michael

2006-01-01

427

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

NASA Astrophysics Data System (ADS)

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.

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

428

Aplysin Sensitizes Cancer Cells to TRAIL by Suppressing P38 MAPK/Survivin Pathway  

PubMed Central

TNF-related apoptosis-inducing ligand (TRAIL) is a tumor-selective apoptosis inducer and has been shown to be promising for treating various types of cancers. However, the application of TRAIL is greatly impeded by the resistance of cancer cells to its action. Studies show that overexpression of some critical pro-survival proteins, such as survivin, is responsible for TRAIL resistance. In this study, we found that Aplysin, a brominated compound from marine organisms, was able to restore the sensitivity of cancer cells to TRAIL both in vitro and in vivo. Aplysin was found to enhance the tumor-suppressing capacity of TRAIL on several TRAIL-resistant cancer cell lines. TRAIL-induced apoptosis was also potentiated in A549 and MCF7 cells treated with Aplysin. Survivin downregulation was identified as a mechanism by which Aplysin-mediated TRAIL sensitization of cancer cells. Furthermore, the activation of p38 MAPK was revealed in Aplysin-treated cancer cells, and its inhibitor SB203580 was able to abrogate the promoting effect of Aplysin on the response of cancer cells to TRAIL action, as evidenced by restored survivin expression, elevated cell survival and reduced apoptotic rates. In conclusion, we provided evidence that Aplysin acts as a sensitizer for TRAIL and its effect on p38 MAPK/survivin pathway may partially account for this activity. Considering its low cytotoxicity to normal cells, Aplysin may be a promising agent for cancer treatment in combination with TRAIL. PMID:25257790

Liu, Jia; Ma, Leina; Wu, Ning; Liu, Ge; Zheng, Lanhong; Lin, Xiukun

2014-01-01

429

Aplysin sensitizes cancer cells to TRAIL by suppressing P38 MAPK/survivin pathway.  

PubMed

TNF-related apoptosis-inducing ligand (TRAIL) is a tumor-selective apoptosis inducer and has been shown to be promising for treating various types of cancers. However, the application of TRAIL is greatly impeded by the resistance of cancer cells to its action. Studies show that overexpression of some critical pro-survival proteins, such as survivin, is responsible for TRAIL resistance. In this study, we found that Aplysin, a brominated compound from marine organisms, was able to restore the sensitivity of cancer cells to TRAIL both in vitro and in vivo. Aplysin was found to enhance the tumor-suppressing capacity of TRAIL on several TRAIL-resistant cancer cell lines. TRAIL-induced apoptosis was also potentiated in A549 and MCF7 cells treated with Aplysin. Survivin downregulation was identified as a mechanism by which Aplysin-mediated TRAIL sensitization of cancer cells. Furthermore, the activation of p38 MAPK was revealed in Aplysin-treated cancer cells, and its inhibitor SB203580 was able to abrogate the promoting effect of Aplysin on the response of cancer cells to TRAIL action, as evidenced by restored survivin expression, elevated cell survival and reduced apoptotic rates. In conclusion, we provided evidence that Aplysin acts as a sensitizer for TRAIL and its effect on p38 MAPK/survivin pathway may partially account for this activity. Considering its low cytotoxicity to normal cells, Aplysin may be a promising agent for cancer treatment in combination with TRAIL. PMID:25257790

Liu, Jia; Ma, Leina; Wu, Ning; Liu, Ge; Zheng, Lanhong; Lin, Xiukun

2014-09-01

430

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

PubMed

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. PMID:25813628

Thompson, Bill

2015-05-01

431

The Prognostic Value of TRAIL and its Death Receptors in Cervical Cancer  

SciTech Connect

Purpose: Preclinical data indicate a synergistic effect on apoptosis between irradiation and recombinant human (rh) tumor necrosis factor-related apoptosis inducing ligand (TRAIL), making the TRAIL death receptors (DR) interesting drug targets. The aim of our study was to analyze the expression of DR4, DR5, and TRAIL in cervical cancer and to determine their predictive and prognostic value. Methods and Materials: Tissue microarrays were constructed from tumors of 645 cervical cancer patients treated with surgery and/or (chemo-)radiation between 1980 and 2004. DR4, DR5, and TRAIL expression in the tumor was studied by immunohistochemistry and correlated to clinicopathological variables, response to radiotherapy, and disease-specific survival. Results: Cytoplasmatic DR4, DR5, and TRAIL immunostaining were observed in cervical tumors from 99%, 88%, and 81% of the patients, respectively. In patients treated primarily with radiotherapy, TRAIL-positive tumors less frequently obtained a pathological complete response than TRAIL-negative tumors (66.3% vs. 79.0 %; in multivariate analysis: odds ratio: 2.09, p {<=}0.05). DR4, DR5, and TRAIL expression were not prognostic for disease-specific survival. Conclusions: Immunostaining for DR4, DR5, and TRAIL is frequently observed in the cytoplasm of tumor cells in cervical cancer patients. Absence of TRAIL expression was associated with a higher pathological complete response rate to radiotherapy. DR4, DR5, or TRAIL were not prognostic for disease-specific survival.

Maduro, John H. [Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Department of Medical Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands)], E-mail: j.h.maduro@rt.umcg.nl; Noordhuis, Maartje G.; Hoor, Klaske A. ten [Department of Gynecologic Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Pras, Elisabeth [Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Arts, Henriette J.G.; Eijsink, Jasper J.H. [Department of Gynecologic Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Hollema, Harry [Department of Pathology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Mom, Constantijne H. [Department of Medical Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Department of Gynecologic Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Jong, Steven de; Vries, Elisabeth G.E. de [Department of Medical Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Bock, Geertruida H. de [Department of Epidemiology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Zee, Ate G.J. van der [Department of Gynecologic Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands)

2009-09-01

432

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

PubMed

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 movements within an area containing lynx and designated lynx habitat. PMID:24367565

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

2013-01-01

433

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

PubMed Central

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 movements within an area containing lynx and designated lynx habitat. PMID:24367565

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

2013-01-01

434

Unmanned Ground Vehicle Perception Using Thermal Infrared Cameras  

NASA Technical Reports Server (NTRS)

The ability to perform off-road autonomous navigation at any time of day or night is a requirement for some unmanned ground vehicle (UGV) programs. Because there are times when it is desirable for military UGVs to operate without emitting strong, detectable electromagnetic signals, a passive only terrain perception mode of operation is also often a requirement. Thermal infrared (TIR) cameras can be used to provide day and night passive terrain perception. TIR cameras have a detector sensitive to either mid-wave infrared (MWIR) radiation (3-5?m) or long-wave infrared (LWIR) radiation (8-12?m). With the recent emergence of high-quality uncooled LWIR cameras, TIR cameras have become viable passive perception options for some UGV programs. The Jet Propulsion Laboratory (JPL) has used a stereo pair of TIR cameras under several UGV programs to perform stereo ranging, terrain mapping, tree-trunk detection, pedestrian detection, negative obstacle detection, and water detection based on object reflections. In addition, we have evaluated stereo range data at a variety of UGV speeds, evaluated dual-band TIR classification of soil, vegetation, and rock terrain types, analyzed 24 hour water and 12 hour mud TIR imagery, and analyzed TIR imagery for hazard detection through smoke. Since TIR cameras do not currently provide the resolution available from megapixel color cameras, a UGV's daytime safe speed is often reduced when using TIR instead of color cameras. In this paper, we summarize the UGV terrain perception work JPL has performed with TIR cameras over the last decade and describe a calibration target developed by General Dynamics Robotic Systems (GDRS) for TIR cameras and other sensors.

Rankin, Arturo; Huertas, Andres; Matthies, Larry; Bajracharya, Max; Assad, Christopher; Brennan, Shane; Bellutta, Paolo; Sherwin, Gary W.

2011-01-01

435

Unmanned ground vehicle perception using thermal infrared cameras  

NASA Astrophysics Data System (ADS)

The ability to perform off-road autonomous navigation at any time of day or night is a requirement for some unmanned ground vehicle (UGV) programs. Because there are times when it is desirable for military UGVs to operate without emitting strong, detectable electromagnetic signals, a passive only terrain perception mode of operation is also often a requirement. Thermal infrared (TIR) cameras can be used to provide day and night passive terrain perception. TIR cameras have a detector sensitive to either mid-wave infrared (MWIR) radiation (3-5?m) or long-wave infrared (LWIR) radiation (7-14?m). With the recent emergence of high-quality uncooled LWIR cameras, TIR cameras have become viable passive perception options for some UGV programs. The Jet Propulsion Laboratory (JPL) has used a stereo pair of TIR cameras under several UGV programs to perform stereo ranging, terrain mapping, tree-trunk detection, pedestrian detection, negative obstacle detection, and water detection based on object reflections. In addition, we have evaluated stereo range data at a variety of UGV speeds, evaluated dual-band TIR classification of soil, vegetation, and rock terrain types, analyzed 24 hour water and 12 hour mud TIR imagery, and analyzed TIR imagery for hazard detection through smoke. Since TIR cameras do not currently provide the resolution available from megapixel color cameras, a UGV's daytime safe speed is often reduced when using TIR instead of color cameras. In this paper, we summarize the UGV terrain perception work JPL has performed with TIR cameras over the last decade and describe a calibration target developed by General Dynamics Robotic Systems (GDRS) for TIR cameras and other sensors.

Rankin, Arturo; Huertas, Andres; Matthies, Larry; Bajracharya, Max; Assad, Christopher; Brennan, Shane; Bellutta, Paolo; Sherwin, Gary W.

2011-05-01

436

Stator Loading Measurements Behind a Fan With Trailing Edge Blowing  

NASA Technical Reports Server (NTRS)

The problem of aircraft noise pollution around airports has become increasingly important as those areas have become more densely populated. Currently, the removal of older noisier aircraft from operation is reducing noise levels around airports; however, with air traffic projected to increase by about 5% over the next decade the number of commercial aircraft operating in the world is expected to be about 17,700 by the year 2007. To keep noise levels around airports from increasing as a result of traffic increases, it is important to investigate new methods of noise reduction. The objective of this work is to provide a better understanding of the effects that trailing edge blowing has on stator unsteady loading. This is done by presenting flowfield and stator loading data from experiments conducted with and without trailing edge blowing.

Waitz, Ian A.

2000-01-01

437

Radio polarisation measurements of meteor trail echoes with BRAMS  

NASA Astrophysics Data System (ADS)

BRAMS, the Belgian RAdio Meteor Stations, is a network of radio receiving stations using forward scatter techniques to detect and characterize meteors. The transmitter is a dedicated beacon located in Dourbes in the south-west of Belgium. It emits towards the zenith a purely sinusoidal wave circularly polarised, at a frequency of 49.97 MHz and with a power of 150 watts. The main goals of the project are to compute meteoroid flux rates and trajectories. Most receiving stations are using a 3 element Yagi antenna and are therefore only sensitive to one polarisation. The station located in Uccle has also a crossed 3 element Yagi antenna and therefore allows measurements of horizontal and vertical polarisations. We present the preliminary radio polarisation measurements of meteor trail echoes and compare them with the theoretical predictions of Jones & Jones (1991) for oblique scattering of radio waves from meteor trails.

Lamy, H.; Ranvier, S.; Anciaux, M.; Calders, S.; De Keyser, J.; Gamby, E.

2012-04-01

438

Single cell motility and trail formation in populations of microglia  

NASA Astrophysics Data System (ADS)

Microglia are a special type of glia cell in brain that has immune responses. They constitute about 20 % of the total glia population within the brain. Compared to other glia cells, microglia are very motile, constantly moving to destroy pathogens and to remove dead neurons. While doing so, they exhibit interesting body shapes, have cell-to-cell communications, and have chemotatic responses to each other. Interestingly, our recent in vitro studies show that their unusual motile behaviors can self-organize to form trails, similar to those in populations of ants. We have studied the changes in the physical properties of these trails by varying the cell population density and by changing the degree of spatial inhomogeneities (``pathogens''). Our experimental observations can be quite faithfully reproduced by a simple mathematical model involving many motile cells whose mechanical motion are driven by actin polymerization and depolymerization process within the individual cell body and by external chemical gradients.

Lee, Kyoung Jin

2009-03-01

439

Low-Speed Fan Noise Reduction With Trailing Edge Blowing  

NASA Technical Reports Server (NTRS)

An experimental proof-of-concept test was conducted to demonstrate reduction of rotor-stator interaction noise through rotor-trailing edge blowing. The velocity deficit from the viscous wake of the rotor blades was reduced by injecting air into the wake from a trailing edge slot. Composite hollow rotor blades with internal flow passages were designed based on analytical codes modeling the internal flow. The hollow blade with interior guide vanes creates flow channels through which externally supplied air flows from the root of the blade to the trailing edge. The impact of the rotor wake-stator interaction on the acoustics was also predicted analytically. The Active Noise Control Fan, located at the NASA Glenn Research Center, was used as the proof- of-concept test bed. In-duct mode and farfield directivity acoustic data were acquired at blowing rates (defined as mass supplied to trailing edge blowing system divided by fan mass flow) ranging from 0.5 to 2.0 percent. The first three blade passing frequency harmonics at fan rotational speeds of 1700 to 1900 rpm were analyzed. The acoustic tone power levels (PWL) in the inlet and exhaust were reduced 11.5 and -0.1, 7.2 and 11.4, 11.8 and 19.4 PWL dB, respectively. The farfield tone power levels at the first three harmonics were reduced 5.4, 10.6, and 12.4 dB PWL. At selected conditions, two-component hotwire and stator vane unsteady surface pressures were acquired. These measurements illustrate the physics behind the noise reduction.

Sutliff, Daniel L.; Tweedt, Daniel L.; Fite, E. Brian; Envia, Edmane

2002-01-01

440

Proceedings IMC Frasso Sabino 1999 5 Leonid Dust Trail Theories  

E-print Network

astronomers Johnstone Stoney and A.M.W. Dow­ ning showed in principle how to predict meteor storms. Their work are perturbed by the planets so as to result in meteor storms at the start of the 21st century. 1 A hundred years: from Stoney and Downing to the 1999 Leonid storm 1.1 IRAS trails and meteor storms In 1983

441

Biomarkers of breast cancer apoptosis induced by chemotherapy and TRAIL.  

PubMed

Treatment of breast cancer is complex and challenging due to the heterogeneity of the disease. To avoid significant toxicity and adverse side-effects of chemotherapy in patients who respond poorly, biomarkers predicting therapeutic response are essential. This study has utilized a proteomic approach integrating 2D-DIGE, LC-MS/MS, and bioinformatics to analyze the proteome of breast cancer (ZR-75-1 and MDA-MB-231) and breast epithelial (MCF-10A) cell lines induced to undergo apoptosis using a combination of doxorubicin and TRAIL administered in sequence (Dox-TRAIL). Apoptosis induction was confirmed using a caspase-3 activity assay. Comparative proteomic analysis between whole cell lysates of Dox-TRAIL and control samples revealed 56 differentially expressed spots (?2-fold change and p < 0.05) common to at least two cell lines. Of these, 19 proteins were identified yielding 11 unique protein identities: CFL1, EIF5A, HNRNPK, KRT8, KRT18, LMNA, MYH9, NACA, RPLP0, RPLP2, and RAD23B. A subset of the identified proteins was validated by selected reaction monitoring (SRM) and Western blotting. Pathway analysis revealed that the differentially abundant proteins were associated with cell death, cellular organization, integrin-linked kinase signaling, and actin cytoskeleton signaling pathways. The 2D-DIGE analysis has yielded candidate biomarkers of response to treatment in breast cancer cell models. Their clinical utility will depend on validation using patient breast biopsies pre- and post-treatment with anticancer drugs. PMID:22133146

Leong, Sharon; McKay, Matthew J; Christopherson, Richard I; Baxter, Robert C

2012-02-01

442

Temperature limits trail following behaviour through pheromone decay in ants  

NASA Astrophysics Data System (ADS)

In Mediterranean habitats, temperature affects both ant foraging behaviour and community structure. Many studies have shown that dominant species often forage at lower temperature than subordinates. Yet, the factors that constrain dominant species foraging activity in hot environments are still elusive. We used the dominant ant Tapinoma nigerrimum as a model species to test the hypothesis that high temperatures hinder trail following behaviour by accelerating pheromone degradation. First, field observations showed that high temperatures (> 30°C) reduce the foraging activity of T. nigerrimum independently of the daily and seasonal rhythms of this species. Second, we isolated the effect of high temperatures on pheromone trail efficacy from its effect on worker physiology. A marked substrate was heated during 10 min (five temperature treatments from 25°C to 60°C), cooled down to 25°C, and offered in a test choice to workers. At hot temperature treatments (>40°C), workers did not discriminate the previously marked substrate. High temperatures appeared therefore to accelerate pheromone degradation. Third, we assessed the pheromone decay dynamics by a mechanistic model fitted with Bayesian inference. The model predicted ant choice through the evolution of pheromone concentration on trails as a function of both temperature and time since pheromone deposition. Overall, our results highlighted that the effect of high temperatures on recruitment intensity was partly due to pheromone evaporation. In the Mediterranean ant communities, this might affect dominant species relying on chemical recruitment, more than subordinate ant species, less dependent on chemical communication and less sensitive to high temperatures.

van Oudenhove, Louise; Billoir, Elise; Boulay, Raphaël; Bernstein, Carlos; Cerdá, Xim

2011-12-01

443

IRAS observations of asteroid dust bands and cometary dust trails  

SciTech Connect

Analysis of data from the infrared Astronomical Satellite (IRAS) resulted in the discovery of bands of dust surrounding the inner solar system, consisting of asteroid collision debris (Low et al., 1984). Narrow trails of dust were also discovered tracking the orbits of a number of short-period comets (Sykes et al., 1986). Pairs of dust bands are the product of individual collisional events in the asteroid belt. A dynamical model is developed that shows how the orbits of debris from such collisions evolve to form a band pair. A model of the surface-area evolution of such bands is also developed which, coupled with asteroid collision theories, indicates that some of the observed dust bands are the consequence of the disruption of approx.10 km diameter asteroids within the last approx.10/sup 7/ years. Observations of other bands are consistent with more ancient disruptions of much larger asteroids, which resulted in the formation of the Koronis and Themis asteroid families. Cometary dust trails consist of particles hundreds of microns and larger in diameter, ejected at low velocities (m/s) from the parent comet, and spreading out ahead and behind the comet's position along its orbital path, the initial stages in the evolution of meteor streams. Preliminary results from a survey of dust trails in the IRAS data indicate the presence of a large number of previously unobserved short-period comets.

Sykes, M.V.

1986-01-01

444

Identification of platinum and palladium particles emitted from vehicles and dispersed into the surface environment.  

PubMed

Platinum, palladium, and rhodium are emitted from vehicle catalytic converters. Until now, the form of precious metal particles in road dust and urban waste has not been identified. This study has located, imaged, and analyzed these particles in road dust and gully waste. Two fragments of catalytic converter have been observed in road dust. They are 40-80 ?m in size and covered in many minute particles (<0.3 ?m) of either platinum with minor rhodium or palladium. One fragment identified in gully sediment is smaller, 25 ?m in diameter, hosting only one attached particle of palladium with minor rhodium. As fragments are washed off roads they begin to disintegrate and the precious metals become detached. Also precious metal-bearing particles have been located in incinerated sewage ash including a 20 ?m diameter cluster of <3 ?m sized platinum particles that may be the remains of a catalytic converter fragment that has survived incineration. The form of these precious metal-bearing particles described here reveals that as they are dispersed from roads they are likely to be present predominantly as two particle sizes. Either they are attached to larger fragments of catalytic converter or they are released as individual detached tiny <0.3 ?m to nanoparticle sizes. PMID:22313190

Prichard, Hazel M; Fisher, Peter C

2012-03-20

445

AMELIA CESTOL Test: Acoustic Characteristics of Circulation Control Wing with Leading-and Trailing-Edge Slot Blowing  

NASA Technical Reports Server (NTRS)

Aeroacoustic measurements of the 11 % scale full-span AMELIA CESTOL model with leading- and trailing-edge slot blowing circulation control (CCW) wing were obtained during a recent test in the Arnold Engineering Development Center 40- by 80-Ft. Wind Tunnel at NASA Ames Research Center, Sound levels and spectra were acquired with seven in-flow microphones and a 48-element phased microphone array for a variety of vehicle configurations, CCW slot flow rates, and forward speeds, Corrections to the measurements and processing are in progress, however the data from selected configurations presented in this report confirm good measurement quality and dynamic range over the test conditions, Array beamform maps at 40 kts tunnel speed show that the trailing edge flap source is dominant for most frequencies at flap angles of 0deg and 60deg, The overall sound level for the 60deg flap was similar to the 0deg flap for most slot blowing rates forward of 90deg incidence, but was louder by up to 6 dB for downstream angles, At 100 kts, the in-flow microphone levels were louder than the sensor self-noise for the higher blowing rates, while passive and active background noise suppression methods for the microphone array revealed source levels as much as 20 dB lower than observed with the in-flow microphones,

Horne, Clifton; Burnside, Nathan J.

2013-01-01

446

Implementation of a Trailing-Edge Flap Analysis Model in the NASA Langley CAMRAD.MOD1/Hires Program  

NASA Technical Reports Server (NTRS)

Continual advances in rotorcraft performance, vibration and acoustic characteristics are being sought by rotary-wing vehicle manufacturers to improve efficiency, handling qualities and community noise acceptance of their products. The rotor system aerodynamic and dynamic behavior are among the key factors which must be addressed to meet the desired goals. Rotor aerodynamicists study how airload redistribution impacts performance and noise, and seek ways to achieve better airload distribution through changes in local aerodynamic response characteristics. One method currently receiving attention is the use of trailing-edge flaps mounted on the rotor blades to provide direct control of a portion of the spanwise lift characteristics. The following work describes the incorporation of a trailing-edge flap model in the CAMRAD.Mod1/FHUS comprehensive rotorcraft analysis code. The CAM-RAD.Mod1/HIRES analysis consists of three separate executable codes. These include the comprehensive trim analysis, CAMRAD.Mod1, the Indicial Post-Processor, IPP, for high resolution airloads, and AIRFOIL, which produces the rotor airfoil tables from input airfoil section characteristics. The modifications made to these components permitting analysis of flapped rotor configurations are documented herein along with user instructions detailing the new input variables and operational notes.

Charles, Bruce

1999-01-01

447

Reactive oxygen species contribute to TRAIL receptors upregulation; the mechanism for PH II-7 augmenting TRAIL induced apoptosis in leukemia cells.  

PubMed

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) can selectively induce apoptosis in cancer cells and is verified to be effective in various cancers. However, a variety of cancer cells are found to be resistant to TRAIL and the mechanisms are largely unknown. Moreover, multidrug resistance to traditional chemotherapeutic agents still remains a tough problem in clinical practice. Fortunately, our previous work proved the ability of PH II-7 in overcoming MDR phenotype through reactive oxygen species production in K562 and its MDR counterpart K562/A02 cells. Additionally, we further explored its potential in augmenting TRAIL induced apoptosis in cancer cells with various tissue origins. Our results showed PH II-7 up-regulated DR4/DR5 expression and augment TRAIL cytotoxicity through reactive oxygen species production, which provide a solid foundation for TRAIL in combination with PH II-7 in future clinical application. PMID:25446561

Peng, Hongwei; Yuan, Xiangfei; Luo, Shiwen; Li, Fei; Wei, Xiaohua; Ye, Zhou; Xiong, Dongsheng

2015-01-01

448

p53-Independent up-regulation of a TRAIL receptor DR5 by proteasome inhibitors: a mechanism for proteasome inhibitor-enhanced TRAIL-induced apoptosis.  

PubMed

Gliomas are the most common brain tumors in adults and account for more than half of all brain tumors. Despite intensive clinical investigations, average survival for the patients harboring the malignancy has not been significantly improved. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), shown to have potent and cancer-selective killing activity, has drawn considerable attention as a promising anti-cancer therapy. In an attempt to develop TRAIL as an anti-cancer therapy for gliomas, tumor suppressor activity of TRAIL was assessed using human glioma cell lines such as U373MG, U343MG, U87MG and LN18. U343MG, U87MG and LN18 cells were susceptible to TRAIL; however, U373MG cells were completely refractory to TRAIL. Resistance to the applied therapies is a key issue in cancer treatment; thus, various combination treatments were evaluated using U373MG cells to identify a better regimen. Unlike Doxorubicin, Etoposide, Actinomycin D and Wortmannin, a proteasome inhibitor MG132 significantly enhanced TRAIL-induced apoptosis. Similarly, other proteasome inhibitors, including Lactacystin, Proteasome inhibitor I and Velcade (Bortezomib), also enhanced apoptotic activity of TRAIL. Among these proteasome inhibitors, Velcade, the only approved drug, was as effective as MG132 in enhancing TRAIL-induced apoptosis. Both Velcade and MG132 increased the protein levels of DR5, a TRAIL receptor known to be up-regulated by p53, in U373MG cells where p53 is mutated. Our data indicate that proteasome inhibitors up-regulate DR5 in a p53-independent manner and a combination therapy comprising TRAIL and Velcade become a better treatment regimen for gliomas. PMID:22120628

Seol, Dai-Wu

2011-12-01

449

Environmental perceptions and objective walking trail audits inform a community-based participatory research walking intervention  

PubMed Central

Background Given the documented physical activity disparities that exist among low-income minority communities and the increased focused on socio-ecological approaches to address physical inactivity, efforts aimed at understanding the built environment to support physical activity are needed. This community-based participatory research (CBPR) project investigates walking trails perceptions in a high minority southern community and objectively examines walking trails. The primary aim is to explore if perceived and objective audit variables predict meeting recommendations for walking and physical activity, MET/minutes/week of physical activity, and frequency of trail use. Methods A proportional sampling plan was used to survey community residents in this cross-sectional study. Previously validated instruments were pilot tested and appropriately adapted and included the short version of the validated International Physical Activity Questionnaire, trail use, and perceptions of walking trails. Walking trails were assessed using the valid and reliable Path Environmental Audit Tool which assesses four content areas including: design features, amenities, maintenance, and pedestrian safety from traffic. Analyses included Chi-square, one-way ANOVA's, multiple linear regression, and multiple logistic models. Results Numerous (n = 21) high quality walking trails were available. Across trails, there were very few indicators of incivilities and safety features rated relatively high. Among the 372 respondents, trail use significantly predicted meeting recommendations for walking and physical activity, and MET/minutes/week. While controlling for other variables, significant predictors of trail use included proximity to trails, as well as perceptions of walking trail safety, trail amenities, and neighborhood pedestrian safety. Furthermore, while controlling for education, gender, and income; for every one time per week increase in using walking trails, the odds for meeting walking recommendations increased 1.27 times, and the odds for meeting PA recommendation increased 3.54 times. Perceived and objective audit variables did not predict meeting physical activity recommendations. Conclusions To improve physical activity levels, intervention efforts are needed to maximize the use of existing trails, as well as improve residents' perceptions related to incivilities, safety, conditions of trail, and amenities of the walking trails. This study provides important insights for informing development of the CBPR walking intervention and informing local recreational and environmental policies in this southern community. PMID:22289653

2012-01-01

450

Microsatellite Instability, KRAS Mutations and Cellular Distribution of TRAIL-Receptors in Early Stage Colorectal Cancer  

PubMed Central

Background The fact that the receptors for the TNF-related apoptosis inducing ligand (TRAIL) are almost invariably expressed in colorectal cancer (CRC) represents the rationale for the employment of TRAIL-receptors targeting compounds for the therapy of patients affected by this tumor. Yet, first reports on the use of these bioactive agents provided disappointing results. We therefore hypothesized that loss of membrane-bound TRAIL-R might be a feature of some CRC and that the evaluation of membrane staining rather than that of the overall expression of TRAIL-R might predict the response to TRAIL-R targeting compounds in this tumor. Aim and Methods Thus, we evaluated the immunofluorescence pattern of TRAIL-receptors and E-cadherin to assess the fraction of membrane-bound TRAIL-receptors in 231 selected patients with early-stage CRC undergoing surgical treatment only. Moreover, we investigated whether membrane staining for TRAIL-receptors as well as the presence of KRAS mutations or of microsatellite instability (MSI) had an effect on survival and thus a prognostic effect. Results As expected, almost all CRC samples stained positive for TRAIL-R1 and 2. Instead, membrane staining for these receptors was positive in only 71% and 16% of samples respectively. No correlation between KRAS mutation status or MSI-phenotype and prognosis could be detected. TRAIL-R1 staining intensity correlated with survival in univariate analysis, but only membranous staining of TRAIL-R1 and TRAIL-R2 on cell membranes was an independent predictor of survival (cox multivariate analysis: TRAIL-R1: p?=?0.019, RR 2.06[1.12–3.77]; TRAIL-R2: p?=?0.033, RR 3.63[1.11–11.84]). Conclusions In contrast to the current assumptions, loss of membrane staining for TRAIL-receptors is a common feature of early stage CRC which supersedes the prognostic significance of their staining intensity. Failure to achieve therapeutic effects in recent clinical trials using TRAIL-receptors targeting compounds might be due to insufficient selection of patients bearing tumors with membrane-bound TRAIL-receptors. PMID:23284732

Kriegl, Lydia; Jung, Andreas; Horst, David; Rizzani, Antonia; Jackstadt, Rene; Hermeking, Heiko; Gallmeier, Eike; Gerbes, Alexander L.; Kirchner, Thomas; Göke, Burkhard; De Toni, Enrico N.

2012-01-01

451

Src and ADAM-17-Mediated Shedding of Transforming Growth Factor-? Is a Mechanism of Acute Resistance to TRAIL  

PubMed Central

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL/Apo-2L) has emerged as a promising anticancer agent. However, resistance to TRAIL is likely to be a major problem, and sensitization of cancer cells to TRAIL may therefore be an important anticancer strategy. In this study, we examined the effect of the epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) gefitinib and a human epidermal receptor 2 (HER2)-TKI (M578440) on the sensitivity of human colorectal cancer (CRC) cell lines to recombinant human TRAIL (rhTRAIL). A synergistic interaction between rhTRAIL and gefitinib and rhTRAIL and M578440 was observed in both rhTRAIL-sensitive and resistant CRC cells. This synergy correlated with an increase in EGFR and HER2 activation after rhTRAIL treatment. Furthermore, treatment of CRC cells with rhTRAIL resulted in activation of the Src family kinases (SFK). Importantly, we found that rhTRAIL treatment induced shedding of transforming growth factor-? (TGF-?) that was dependent on SFK activity and the protease ADAM-17. Moreover, this shedding of TGF-? was critical for rhTRAIL-induced activation of EGFR. In support of this, SFK inhibitors and small interfering RNAs targeting ADAM-17 and TGF-? also sensitized CRC cells to rhTRAIL-mediated apoptosis. Taken together, our findings indicate that both rhTRAIL-sensitive and resistant CRC cells respond to rhTRAIL treatment by activating an EGFR/HER2-mediated survival response and that these cells can be sensitized to rhTRAIL using EGFR/HER2-targeted therapies. Furthermore, this acute response to rhTRAIL is regulated by SFK-mediated and ADAM-17-mediated shedding of TGF-?, such that targeting SFKs or inhibiting ADAM-17, in combination with rhTRAIL, may enhance the response of CRC tumors to rhTRAIL. PMID:18922903

Van Schaeybroeck, Sandra; Kelly, Donal M.; Kyula, Joan; Stokesberry, Susan; Fennell, Dean A.; Johnston, Patrick G.; Longley, Daniel B.

2008-01-01

452

Cosmeceutical vehicles.  

PubMed

Consumers will pay a premium for high-performance skin and hair care products. The demand exists, and in return for the high cost, consumers expect the product to perform as claimed and to meet aesthetic standards beyond many products found in the mass market. To be successful in this highly competitive market, products must function as claimed or consumers will not repurchase. Effective contemporary high-end products must be properly formulated in nonirritating vehicles that consumers will perceive as elegant. PMID:19695476

Epstein, Howard

2009-01-01

453

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

SciTech Connect

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. An assessment is made of future research opportunities in trailing edge noise reduction for wind turbine rotors.

Barone, Matthew Franklin

2011-08-01

454

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

PubMed

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. PMID:25386724

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

2015-01-01

455

Unmanned Vehicle Situation Awareness  

Microsoft Academic Search

This paper presents the concept of unmanned vehicle situation awareness and provides a discussion of how unmanned vehicle situation awareness can be defined based upon human situation awareness. A broadly accepted human situation awareness definition is directly applied to the notion of unmanned vehicle situation awareness. The paper also discusses unique unmanned vehicle aspects that will influence unmanned vehicle situation

Julie A. Adams

456

Brief Communication: Associations of Serum TRAIL Concentrations, Anthropometric Variables, and Serum Lipid Parameters in Healthy Adults  

Microsoft Academic Search

To investigate the relationships of tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL), anthropometric variables, and lipid parameters, we measured serum TRAIL concentrations, body mass index (BMI), total body fat (TBF), and serum lipid profiles in 207 healthy adults. There were no significant differences in serum TRAIL concentrations between men and women, nor between elderly persons and middle-aged subjects. However, men

Jong Weon Choi; Jung Soo Song; Soo Hwan Pai

2004-01-01

457

Characterizing Meteors and the Signal Dependence of Nonspecular Trails with Aspect Angle  

NASA Astrophysics Data System (ADS)

High Power, Large Aperture (HPLA) Radars have been used to characterize the plasmas formed as meteoroids ablate in Earth's atmosphere. These plasmas are referred to as heads, which are the plasmas surrounding the meteoroids, and trails, which are plasmas behind the meteoroids. Meteor trails are further categorized as specular trails, which are detected when the radar beam is perpendicular to the meteoroid's path, and nonspecular trails, which are detected when the radar beam is quasi-perpendicular to the magnetic field. Specular trails are thought to be from Fresnel scattering of the plasma, whereas nonspecular trails are thought to be the reflection from field aligned irregularities (FAIs) that form due to the onset of turbulence in the meteor trail. We present research on these meteors detected by the Advanced Research Project Agency (ARPA) Long-range Tracking and Identification Radar (ALTAIR) in 2007. These data include dual frequency, dual polarized, and high range resolution in-phase (I) and quadrature (Q) returns with additional azimuth and elevation data derived from the monopulse system. We investigate statistical measurements of the meteors including head echo velocities and radar cross sections, correlations of the time duration of nonspecular trails with the respective head echoes, detection rates of head echoes and nonspecular trails, and maximum signal to noise ratio. We also examine the altitude dependence of these meteor parameters. The second part of our investigation includes an aspect sensitivity study of the nonspecular trails detected. We show that there is a decrease in nonspecular trail detections as the angle between the radar boresight and the magnetic field lines is shifted away from perpendicular, with a sharp fall off below 78-80 degrees. This result demonstrates the significance that the radar boresight must be quasi-perpendicular to the magnetic field in order to detect nonspecular trails.

Yee, J.; Close, S.

2012-12-01

458

Evidence of practice effects in variants of the Trail Making Test during serial assessment  

Microsoft Academic Search

Practice effects often obscure detection of meaningful intraindividual cognitive change in serial assessment. The Trail Making Test and four of its variants (i.e., Trail Making Test of the Delis–Kaplan Executive Functioning System, Comprehensive Trail Making Test, Connections Task, and Planned Connections) were administered to college-aged participants over a 3-week period with 7 days separating each session. Linear growth analysis yielded

Kristen K. Buck; Thomas M. Atkinson; Jeanne P. Ryan

2008-01-01

459

P-glycoprotein-dependent resistance of cancer cells toward the extrinsic TRAIL apoptosis signaling pathway.  

PubMed

The TNF-related apoptosis-inducing ligand (TRAIL or Apo2L) preferentially cause apoptosis of malignant cells in vitro and in vivo without severe toxicity. Therefore, TRAIL or agonist antibodies to the TRAIL DR4 and DR5 receptors are used in cancer therapy. However, many malignant cells are intrinsically resistant or acquire resistance to TRAIL. It has been previously proposed that the multidrug transporter P-glycoprotein (Pgp) might play a role in resistance of cells to intrinsic apoptotic pathways by interfering with components of ceramide metabolism or by modulating the electrochemical gradient across the plasma membrane. In this study we investigated whether Pgp also confers resistance toward extrinsic death ligands of the TNF family. To this end we focused our study on HeLa cells carrying a tetracycline-repressible plasmid system which shuts down Pgp expression in the presence of tetracycline. Our findings demonstrate that expression of Pgp is a significant factor conferring resistance to TRAIL administration, but not to other death ligands such as TNF-? and Fas ligand. Moreover, blocking Pgp transport activity sensitizes the malignant cells toward TRAIL. Therefore, Pgp transport function is required to confer resistance to TRAIL. Although the resistance to TRAIL-induced apoptosis is Pgp specific, TRAIL itself is not a direct substrate of Pgp. Pgp expression has no effect on the level of the TRAIL receptors DR4 and DR5. These findings might have clinical implications since the combination of TRAIL therapy with administration of Pgp modulators might sensitize TRAIL resistant tumors. PMID:23774624

Galski, Hanan; Oved-Gelber, Tamar; Simanovsky, Masha; Lazarovici, Philip; Gottesman, Michael M; Nagler, Arnon

2013-09-01

460

Effects of the Built Environment on Childhood Obesity: the Case of Urban Recreational Trails and Crime  

PubMed Central

We study the effects of urban environment on childhood obesity by concentrating on the effects of walking trails and crime close to children’s homes on their BMI and obesity status. We use a unique dataset, which combines information on recreational trails in Indianapolis with data on violent crimes and anthropomorphic and diagnostic data from children’s clinic visits between 1996 and 2005. We find that having a trail near a home reduces children’s weight. However, the effect depends on the amount of nearby violent crimes. Significant reductions occur only in low crime areas and trails could have opposite effects on weight in high crime areas. These effects are primarily among boys, older children, and children who live in higher income neighborhoods. Evaluated at the mean length of trails this effect for older children in no crime areas would be a reduction of two pounds of the body weight. Falsification tests using planned trails instead of existing trails, show that trails are more likely to be located in areas with heavier children, suggesting that our results on effects of trails represent a lower bound. PMID:22459489

Sandy, Robert; Tchernis, Rusty; Wilson, Jeff; Liu, Gilbert; Zhou, Xilin

2012-01-01

461

TRAIL Modulates the Immune System and Protects against the Development of Diabetes  

PubMed Central

TRAIL or tumor necrosis factor (TNF) related apoptosis-inducing ligand is a member of the TNF superfamily of proteins, whose best characterized function is the induction of apoptosis in tumor, infected, or transformed cells through activation of specific receptors. In nontransformed cells, however, the actions of TRAIL are less well characterized. Recent studies suggest that TRAIL may be implicated in the development and progression of diabetes. Here we review TRAIL biological actions, its effects on the immune system, and how and to what extent it has been shown to protect against diabetes.

Bossi, Fleur; Bernardi, Stella; Zauli, Giorgio; Secchiero, Paola; Fabris, Bruno

2015-01-01

462

Effects of the built environment on childhood obesity: the case of urban recreational trails and crime.  

PubMed

We study the effects of urban environment on childhood obesity by concentrating on the effects of walking trails and crime close to children's homes on their BMI and obesity status. We use a unique dataset, which combines information on recreational trails in Indianapolis with data on violent crimes and anthropomorphic and diagnostic data from children's clinic visits between 1996 and 2005. We find that having a trail near a home reduces children's weight. However, the effect depends on the amount of nearby violent crimes. Significant reductions occur only in low crime areas and trails could have opposite effects on weight in high crime areas. These effects are primarily among boys, older children, and children who live in higher income neighborhoods. Evaluated at the mean length of trails this effect for older children in no crime areas would be a reduction of 2 lb of the body weight. Falsification tests using planned trails instead of existing trails, show that trails are more likely to be located in areas with heavier children, suggesting that our results on effects of trails represent a lower bound. PMID:22459489

Sandy, Robert; Tchernis, Rusty; Wilson, Jeffrey; Liu, Gilbert; Zhou, Xilin

2013-01-01

463

The contact allergen nickel sensitizes primary human endothelial cells and keratinocytes to TRAIL-mediated apoptosis  

PubMed Central

Abstract Primary endothelial cells are fully resistant to TNF-related apoptosis-inducing ligand (TRAIL)-mediated apoptosis. Here, we demonstrate that certain environmental conditions, such as exposure to the widespread allergen nickel, can dramatically increase the susceptibility of naturally resistant primary endothelial cells or keratinocytes to TRAIL-induced apoptosis. While nickel treatment increased surface expression of the apoptosis-inducing TRAIL receptors TRAIL-R1 and TRAIL-R2, it also up-regulated the apoptosis-deficient TRAIL-R4, suggesting that modulation of TRAIL receptor expression alone is unlikely to fully account for the dramatic sensitization effect of nickel. Further analysis of candidate mediators revealed that nickel strongly repressed c-FLIP at mRNA and protein levels. Accordingly, increased activation of Caspase-8 and Caspase-3 following nickel treatment was observed. Importantly, depletion of c-FLIP by RNA interference could largely recapitulate the effect of nickel and sensitize endothelial cells to TRAIL-dependent apoptosis in the absence of nickel pre-treatment. Conversely, ectopic expression of c-FLIPL largely protected nickel-treated cells from TRAIL-mediated apoptosis. Our data demonstrate that one key mechanism of sensitization of primary human endothelial cells or keratinocytes is transcriptional down-regulation of c-FLIP. We hypothesize that environmental factors, exemplified by the contact allergen nickel, strongly modulate death ligand sensitivity of endothelial cells and keratinocytes thus influencing vascular and epidermal function and integrity under physiological and pathophysiological conditions. PMID:19538462

Schmidt, Marc; Hupe, Mike; Endres, Nicole; Raghavan, Badrinarayanan; Kavuri, Shyam; Geserick, Peter; Goebeler, Matthias; Leverkus, Martin

2010-01-01

464

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

USGS Publications Warehouse

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.

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

1991-01-01

465

Combination Anticancer Nanopreparations of Novel Proapoptotic Drug, TRAIL and siRNA  

NASA Astrophysics Data System (ADS)

Development of drugs for the treatment of cancer is a challenging endeavor often hindered by the solubility and distribution of the drug in the body. Drug delivery systems have been used for many years to overcome these issues. Polyethylene glycol-phosphatidylethanolamine (PEG-PE) micelles in particular have shown utility as a nanosized drug delivery vehicle capable of incorporating poorly soluble drugs and preferentially delivering them to the tumor. Addition of PEG polymers to the surface prolongs the half-life of the particle in the blood by evading clearance by the reticuloendothelial system (RES) and increases tumor accumulation through the utilization of the enhanced permeability and retention (EPR) effect. Micelles have also been shown to successfully incorporate and protect modified siRNA, a notoriously challenging therapeutic to deliver. Additionally, co-delivery of multiple therapeutics in multifunctional micelles has emerged as an important area in combination therapy research. The main goal of this project was to develop a multifunctional PEG-PE micellar delivery system capable of delivering multiple therapeutics for increased anti-tumor activity. Previous studies have indicated the utility of a DM-PIT-1, a member of a class of novel PIP3-PH inhibitors, and its potential in the treatment of cancer. The PIP3-kinase (PI3K) pathway has been shown to have serious implications in cancer. Inhibiting this pathway has been shown to sensitize the cell to apoptosis. A second generation of more potent and druggable compounds has been developed based on the structure of DM- PIT-1. However, it has been difficult to develop successful compounds inhibiting PIP3 signaling while maintaining the physicochemical properties necessary for an effective drug. Many of these compounds are limited by their poor solubility and rapid clearance in vivo. Incorporating these compounds into PEG-PE micelles allows for increased solubility, prolonged half-life and tumor accumulation. The addition of TNFa-related apoptosis-inducing ligand (TRAIL) bound to the surface of the micelle creates a combination micelle with excellent cytotoxic effects. TRAIL has been shown to be an effective apoptosis inducing ligand in a variety of in vitro and in vivo studies. TRAIL receptors are preferentially expressed on many cancer cell types as compared to healthy cells making this ligand an intriguing potential therapy. The combination of TRAIL and PIP3-PH inhibitors in a micellar delivery system has the potential to create a powerful anti-cancer therapeutic. Including modified siRNA to down regulate cancer defense mechanisms can further sensitize the cell to apoptosis. siRNA delivery has been shown to be a difficult task. Rapid metabolism and clearance in the blood hinders their ability to reach the tumor. Additionally, their large size and negative charge prevents them from crossing the cell membrane to reach their location of action. Reversibly conjugating a modified siRNA to a lipid thereby creating an siRNA-S-S-PE, allows for their incorporation into PEG-PE micelles. These mixed micelles have been shown to protect the siRNA and successfully transfect cells. This study aimed to combine the aforementioned therapeutics into a multifunctional PEG-PE based micelle delivery system. Novel proapoptotic drugs targeting the PIP3-PH binding domain have been successfully incorporated into the lipid core of the micelle. These drugs were able to effectively sensitize the cell to the effects of surface-bound TRAIL. Additionally, siRNA targeting the anti-apoptotic protein survivin was shown to be incorporated into the micelles and further sensitize the tumor to the effects of the above compounds. Lastly, conjugating transferrin (TF) to the surface of the micelle was shown increase the tumor cell targeting and cytotoxicity in vitro. Critical evaluation of this system was performed along the following specific aims: (1) characterization of PIP3-PH inhibition and cytotoxicity of proapoptotic drug DM-PIT-1 and its novel analogs in vitro with and without TRAIL; (2) preparatio

Riehle, Robert D.

466

Sodium arsenite accelerates TRAIL-mediated apoptosis in melanoma cells through upregulation of TRAIL-R1/R2 surface levels and downregulation of cFLIP expression  

SciTech Connect

AP-1/cJun, NF-{kappa}B and STAT3 transcription factors control expression of numerous genes, which regulate critical cell functions including proliferation, survival and apoptosis. Sodium arsenite is known to suppress both the IKK-NF-{kappa}B and JAK2-STAT3 signaling pathways and to activate the MAPK/JNK-cJun pathways, thereby committing some cancers to undergo apoptosis. Indeed, sodium arsenite is an effective drug for the treatment of acute promyelocytic leukemia with little nonspecific toxicity. Malignant melanoma is highly refractory to conventional radio- and chemotherapy. In the present study, we observed strong effects of sodium arsenite treatment on upregulation of TRAIL-mediated apoptosis in human and mouse melanomas. Arsenite treatment upregulated surface levels of death receptors, TRAIL-R1 and TRAIL-R2, through increased translocation of these proteins from cytoplasm to the cell surface. Furthermore, activation of cJun and suppression of NF-{kappa}B by sodium arsenite resulted in upregulation of the endogenous TRAIL and downregulation of the cFLIP gene expression (which encodes one of the main anti-apoptotic proteins in melanomas) followed by cFLIP protein degradation and, finally, by acceleration of TRAIL-induced apoptosis. Direct suppression of cFLIP expression by cFLIP RNAi also accelerated TRAIL-induced apoptosis in these melanomas, while COX-2 suppression substantially increased levels of both TRAIL-induced and arsenite-induced apoptosis. In contrast, overexpression of permanently active AKTmyr inhibited TRAIL-mediated apoptosis via downregulation of TRAIL-R1 levels. Finally, AKT overactivation increased melanoma survival in cell culture and dramatically accelerated growth of melanoma transplant in vivo, highlighting a role of AKT suppression for effective anticancer treatment.

Ivanov, Vladimir N. [Center for Radiological Research, Columbia University College of Physicians and Surgeons, Columbia University, New York, NY 10032 (United States)]. E-mail: vni3@columbia.edu; Hei, Tom K. [Center for Radiological Research, Columbia University College of Physicians and Surgeons, Columbia University, New York, NY 10032 (United States); Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY 10032 (United States)

2006-12-10

467

The structure of trailing vortices generated by model rotor blades  

NASA Technical Reports Server (NTRS)

Hot-wire anemometry to analyze the structure and geometry of rotary wing trailing vortices is studied. Tests cover a range of aspect ratios and blade twist. For all configurations, measured vortex strength correlates well with maximum blade-bound circulation. Measurements of wake geometry are in agreement with classical data for high-aspect ratios. The detailed vortex structure is similar to that found for fixed wings and consists of four well defined regions--a viscous core, a turbulent mixing region, a merging region, and an inviscid outer region. A single set of empirical formulas for the entire set of test data is described.

Tung, C.; Pucci, S. L.; Caradonna, F. X.; Morse, H. A.

1981-01-01

468

Application of Improved Grammatical Evolution to Santa Fe Trail Problems  

NASA Astrophysics Data System (ADS)

Grammatical Evolution (GE) is one of the evolutionary algorithms, which can deal with the rules with tree structure by one-dimensional chromosome. Syntax rules are defined in Backus Naur Form (BNF) to translate binary number (genotype) to function or program (phenotype). In this study, three algorithms are introduced for improving the convergence speed. First, an original GE are compared with Genetic Programming (GP) in the function identification problem. Next, the improved GE algorithms are applied to Santa Fe Trail problem. The results show that the improved schemes are effective for improving the convergence speed.

Kuroda, Takuya; Iwasawa, Hiroto; Awgichew, Tewodros; Kita, Eisuke

469

Computational Aeroacoustic Analysis of Slat Trailing-Edge Flow  

NASA Technical Reports Server (NTRS)

An acoustic analysis based on the Ffowcs Williams and Hawkings equation was performed for a high-lift system. As input, the acoustic analysis used un- steady flow data obtained from a highly resolved, time-dependent, Reynolds-averaged Navier-Stokes calculation. The analysis strongly suggests that vor- tex shedding from the trailing edge of the slat results in a high-amplitude, high-frequency acoustic signal, similar to that which was observed in a correspond- ing experimental study of the high-lift system.

Singer, Bart A.; Lockhard, David P.; Brentner, Kenneth S.; Khorrami, Mehdi R.; Berkman, Mert E.; Choudhari, Meelan

2000-01-01

470

Robotica (2012) volume 30, pp. 491503. Cambridge University Press 2011 doi:10.1017/S0263574711000798  

E-print Network

code for vehicle dynamics, simulation studies of various off-road conditions in three by Wong6,7 to form an important element of off-road vehicle dynamics. In ref. [8], Wong proposed extensive work is required to fit this model into other vehicle configurations. Also, specific vehicle

Peng, Huei

471

Toward the Improvement of Trail Classification in National Parks Using the Recreation Opportunity Spectrum Approach  

NASA Astrophysics Data System (ADS)

Trail settings in national parks are essential management tools for improving both ecological conservation efforts and the quality of visitor experiences. This study proposes a plan for the appropriate maintenance of trails in Chubusangaku National Park, Japan, based on the recreation opportunity spectrum (ROS) approach. First, we distributed 452 questionnaires to determine park visitors' preferences for setting a trail (response rate = 68 %). Respondents' preferences were then evaluated according to the following seven parameters: access, remoteness, naturalness, facilities and site management, social encounters, visitor impact, and visitor management. Using nonmetric multidimensional scaling and cluster analysis, the visitors were classified into seven groups. Last, we classified the actual trails according to the visitor questionnaire criteria to examine the discrepancy between visitors' preferences and actual trail settings. The actual trail classification indicated that while most developed trails were located in accessible places, primitive trails were located in remote areas. However, interestingly, two visitor groups seemed to prefer a well-conserved natural environment and, simultaneously, easily accessible trails. This finding does not correspond to a premise of the ROS approach, which supposes that primitive trails should be located in remote areas without ready access. Based on this study's results, we propose that creating trails, which afford visitors the opportunity to experience a well-conserved natural environment in accessible areas is a useful means to provide visitors with diverse recreation opportunities. The process of data collection and analysis in this study can be one approach to produce ROS maps for providing visitors with recreational opportunities of greater diversity and higher quality.

Oishi, Yoshitaka

2013-06-01

472

Toward the improvement of trail classification in national parks using the recreation opportunity spectrum approach.  

PubMed

Trail settings in national parks are essential management tools for improving both ecological conservation efforts and the quality of visitor experiences. This study proposes a plan for the appropriate maintenance of trails in Chubusangaku National Park, Japan, based on the recreation opportunity spectrum (ROS) approach. First, we distributed 452 questionnaires to determine park visitors' preferences for setting a trail (response rate = 68 %). Respondents' preferences were then evaluated according to the following seven parameters: access, remoteness, naturalness, facilities and site management, social encounters, visitor impact, and visitor management. Using nonmetric multidimensional scaling and cluster analysis, the visitors were classified into seven groups. Last, we classified the actual trails according to the visitor questionnaire criteria to examine the discrepancy between visitors' preferences and actual trail settings. The actual trail classification indicated that while most developed trails were located in accessible places, primitive trails were located in remote areas. However, interestingly, two visitor groups seemed to prefer a well-conserved natural environment and, simultaneously, easily accessible trails. This finding does not correspond to a premise of the ROS approach, which supposes that primitive trails should be located in remote areas without ready access. Based on this study's results, we propose that creating trails, which afford visitors the opportunity to experience a well-conserved natural environment in accessible areas is a useful means to provide visitors with diverse recreation opportunities. The process of data collection and analysis in this study can be one approach to produce ROS maps for providing visitors with recreational opportunities of greater diversity and higher quality. PMID:23615956

Oishi, Yoshitaka

2013-06-01

473

Modernisation and children's blood pressure: On and off the tourist trail in Nepal.  

PubMed

Blood pressure and anthropometric measurements were taken for 231 children between 11 and 14 years in the Annapurna area of Central Nepal, a popular tourist destination. Children from villages on the tourist trail, whose lifestyles were generally more modernised, were compared with children from nearby villages off the tourist trail. Indications of greater modernisation on the trail included the findings that fathers of children living on the trail were less likely to work as farmers than fathers of those off the trail (P = 0.003), and children living on the trail were much more likely to have seen television (P < 0.001). Children on the tourist trail were taller and heavier (P < 0.001), and had higher body mass indices (P = 0.003) and biceps skinfolds (P = 0.005). They also had higher diastolic blood pressure than children living off the trail (P = 0.02). The differences in weight appeared to account for the effect of living on the trail on diastolic blood pressure, since when weight was added to the model it showed a significant association with diastolic blood pressure (P = 0.02) and the effect of location became nonsignificant. For the biceps skinfold and systolic blood pressure, there was a significant sex difference in the effect of living on the trail (P = 0.04 and P = 0.05 respectively), such that among girls there were greater increases associated with living on the trail than there were among boys. The findings suggest that lifestyle changes linked to the development of tourism in Nepal are associated from an early age with potentially deleterious changes in cardiovascular characteristics and demonstrate that such socioeconomic changes can have quite local effects. Am. J. Hum. Biol. 12:478-486, 2000. Copyright 2000 Wiley-Liss, Inc. PMID:11534039

Pollard, Tessa M.; Ward, Gill A.; Thornley, Jeremy; Wooster, Gordon; Wooster, Jeanette; Panter-Brick, Catherine

2000-07-01

474

Trail Communication Regulated by Two Trail Pheromone Components in the Fungus-Growing Termite Odontotermes formosanus (Shiraki)  

PubMed Central

The eusocial termites are well accomplished in chemical communication, but how they achieve the communication using trace amount of no more than two pheromone components is mostly unknown. In this study, the foraging process and trail pheromones of the fungus-growing termite Odontotermes formosanus (Shiraki) were systematically studied and monitored in real-time using a combination of techniques, including video analysis, solid-phase microextraction, gas chromatography coupled with either mass spectrometry or an electroantennographic detector, and bioassays. The trail pheromone components in foraging workers were (3Z)-dodec-3-en-1-ol and (3Z,6Z)-dodeca-3,6-dien-1-ol secreted by their sternal glands. Interestingly, ratio of the two components changed according to the behaviors that the termites were displaying. This situation only occurs in termites whereas ratios of pheromone components are fixed and species-specific for other insect cuticular glands. Moreover, in bioassays, the active thresholds of the two components ranged from 1 fg/cm to 10 pg/cm according to the behavioral contexts or the pheromonal exposure of tested workers. The two components did not act in synergy. (3Z)-Dodec-3-en-1-ol induced orientation behavior of termites that explore their environment, whereas (3Z,6Z)-dodeca-3,6-dien-1-ol had both an orientation effect and a recruitment effect when food was discovered. The trail pheromone of O. formosanus was regulated both quantitatively by the increasing number of workers involved in the early phases of foraging process, and qualitatively by the change in ratio of the two pheromone components on sternal glandular cuticle in the food-collecting workers. In bioassays, the responses of workers to the pheromone were also affected by the variation in pheromone concentration and component ratio in the microenvironment. Thus, this termite could exchange more information with nestmates using the traces of the two trail pheromone components that can be easily regulated within a limited microenvironment formed by the tunnels or chambers. PMID:24670407

Wen, Ping; Ji, Bao-Zhong; Sillam-Dussès, David

2014-01-01

475

Modern Day Voyageurs Seek Out the Growing Network of Water Trails  

NSDL National Science Digital Library

House votes to maintain Gateways Networkhttp://www.bayjournal.com/article.cfm?article=3379California Coastal Conservancy: San Francisco Bay Area Water Trail [pdf]http://www.scc.ca.gov/Bay%20Program/Water_Trail/SFBAWT.htmAmerican Canoe Association: Water Trails Databasehttp://www.americancanoe.org/recreation/watertrails.lassoCongaree River Blue Trail Guidehttp://congareeriverbluetrail.blogspot.com/Northeastern Illinois Regional Water Trails Maphttp://www.openlands.org/watertrails.asp?pgid=11910 scenic spots with no carshttp://edition.cnn.com/2008/TRAVEL/getaways/07/08/no.cars/Most people are probably familiar with cultural trails and markers that point out land-based features and the like, but how about the world of water trails? It might strike some as odd to create a water trail, but an increasing number of organizations and government entities are doing just that. Essentially, a water trail creates a template for water-based travel, and usually for leisure excursions. Visitors are free to use the markers along the trail as they see fit, and follow them in any order they wish. One area that is fairly well documented is the San Francisco Bay, and the California Coastal Conservancy has been working on implementing a vast network of water trails. Many of the sites along this particular water trail had already been in use as picnic sites and so on, but this latest effort will offer visitors a more detailed vision for their future water-based explorations. Of course, these projects are going all around the country, so interested parties should browse around their own regions for like-minded efforts. Perhaps Conservancy project manager Ann Buell said it best when she recently opined "Having a water trail right here makes much more sense than driving off to some faraway lake to find your fun." The first link will take users to an article from this Tuesday's New York Times about the water trails in the San Francisco Bay. The second link leads to an article from the Chesapeake Bay Journal about a recent House of Representatives vote that created additional assistance for the Chesapeake Bay Gateways and Water Trails Network. Moving on, the third link leads to information on the plans for the San Francisco Bay Area Water Trail, provided courtesy of the California Coastal Conservancy. The fourth link leads to the American Canoe Association's Water Trails Database. Here visitors can learn about water trails in their own region and it may even spark an idea for an upcoming vacation or day trip. The fifth link leads to the very excellent online water trail guide to the Congaree River in South Carolina. The sixth link whisks users away to the equally fine interactive Northeastern Illinois Regional Water Trails map, complete with detailed information on each potential water trail. Finally, the last link leads to a nice feature from CNN Travel about 10 places where visitors will see nary a car, including Michigan's Mackinac Island and Monhegan Island off the coast of Maine.

Grinnell, Max

476

Trailing edge noise theory for rotating blades in uniform flow  

E-print Network

This paper presents a new formulation for trailing edge noise radiation from rotating blades based on an analytical solution of the convective wave equation. It accounts for distributed loading and the effect of mean flow and spanwise wavenumber. A commonly used theory due to Schlinker and Amiet (1981) predicts trailing edge noise radiation from rotating blades. However, different versions of the theory exist; it is not known which version is the correct one and what the range of validity of the theory is. This paper addresses both questions by deriving Schlinker and Amiet's theory in a simple way and by comparing it to the new formulation, using model blade elements representative of a wind turbine, a cooling fan and an aircraft propeller. The correct form of Schlinker and Amiet's theory (1981) is identified. It is valid at high enough frequency, i.e. for a Helmholtz number relative to chord greater than one and a rotational frequency much smaller than the angular frequency of the noise sources.

Sinayoko, Samuel; Agarwal, Anurag

2013-01-01

477

Experimental testing of spanwise morphing trailing edge concept  

NASA Astrophysics Data System (ADS)

Aircraft wings with smooth, hinge-less morphing ailerons exhibit increased chordwise aerodynamic efficiency over conventional hinged ailerons. Ideally, the wing would also use these morphing ailerons to smoothly vary its airfoil shape between spanwise stations to optimize the lift distribution and further increase aerodynamic efficiency. However, the mechanical complexity or added weight of achieving such a design has traditionally exceeded the potential aerodynamic gains. By expanding upon the previously developed cascading bimorph concept, this work uses embedded Macro-Fiber Composites and a flexure box mechanism, created using multi-material 3D printing, to achieve the Spanwise Morphing Trailing Edge (SMTE) concept. The morphing actuators are spaced spanwise along the wing with an elastomer spanning the gaps between them, which allows for optimization of the spanwise lift distribution while maintaining the continuity and efficiency of the morphing trailing edge. The concept is implemented in a representative section of a UAV wing with a 305 mm chord. A novel honeycomb skin is created from an elastomeric material using a 3D printer. The actuation capabilities of the concept are evaluated with and without spanning material on a test stand, free of aerodynamic loads. In addition, the actuation restrictions of the spanning elastomer, necessary in adapting the morphing concept from 2D to 3D, are characterized. Initial aerodynamic results from the 1'×1' wind-tunnel also show the effects of aerodynamic loading on the actuation range of the SMTE concept for uniform morphing.

Pankonien, Alexander; Inman, Daniel J.

2013-04-01

478

Eruptive Current Sheets Trailing SOHO/LASCO CMEs  

NASA Astrophysics Data System (ADS)

Current sheets are important signatures of magnetic reconnection during the eruption of solar magnetic structures. Many models of eruptive flare/Coronal Mass Ejections (CMEs) involve formation of a current sheet connecting the ejecting CME flux rope with the post-eruption magnetic loop arcade. Current sheets have been interpreted in white light images as narrow rays trailing the outward-moving CME, in ultraviolet spectra as narrow, bright hot features, and with different manifestations in other wavebands. This study continues that of Webb et al. (2003), who analyzed SMM white light CMEs having candidate magnetic disconnection features at the base of the CME. About half of those were followed by coaxial, bright rays suggestive of newly formed current sheets, and Webb et al. (2003) presented detailed results of analysis of those structures. In this work we extend the study of white light eruptive current sheets to the more sensitive and extensive SOHO/LASCO coronagraph data on CMEs. We comprehensively examined all LASCO CMEs during two periods that we identify with the minimum and maximum activity of solar cycle 23. We identified ~130 ray/current sheets during these periods, nearly all of which trailed CMEs with concave-outward backs. The occurrence rate of the ray/current sheets is 6-7% of all CMEs, irrespective of the solar cycle. We analyze the rays for durations, speeds, alignments, and motions and compare the observational results with some model predictions.

Webb, David F.

2015-04-01

479

Flutter Stability Verified for the Trailing Edge Blowing Fan  

NASA Technical Reports Server (NTRS)

The TURBO-AE aeroelastic code has been used to verify the flutter stability of the trailing edge blowing (TEB) fan, which is a unique technology demonstrator being designed and fabricated at the NASA Glenn Research Center for testing in Glenn s 9- by 15-Foot Low-Speed Wind Tunnel. Air can be blown out of slots near the trailing edges of the TEB fan blades to fill in the wakes downstream of the rotating blades, which reduces the rotor-stator interaction (tone) noise caused by the interaction of wakes with the downstream stators. The TEB fan will demonstrate a 1.6-EPNdB reduction in tone noise through wake filling. Furthermore, the reduced blade-row interaction will decrease the possibility of forced-response vibrations and enable closer spacing of blade rows, thus reducing engine length and weight. The detailed aeroelastic analysis capability of the three-dimensional Navier-Stokes TURBO-AE code was used to check the TEB fan rotor blades for flutter stability. Flutter calculations were first performed with no TEB flow; then select calculations were repeated with TEB flow turned on.

Bakhle, Milind A.; Srivastava, Rakesh

2005-01-01

480

The influence of trailed vorticity on flutter speed estimations  

NASA Astrophysics Data System (ADS)

This paper briefly describes the implementation of a coupled near and far wake model for wind turbine rotor induction in the aeroelastic code HAWC2 and its application for flutter analysis of the NREL 5 MW wind turbine. The model consists of a far wake part based on Blade Element Momentum (BEM) theory, which is coupled with Beddoes' near wake model for trailed vorticity. The first part of this work outlines the implementation in HAWC2, with a focus on the interaction of the induction from the blade based near wake model with the induction from the polar grid based BEM model in HAWC2. The influence of the near wake model on the aeroelastic stability of the blades of the NREL 5 MW turbine in overspeed conditions is investigated in the second part of the paper. The analysis is based on a runaway case in which the turbine is free to speed up without generator torque and vibrations start building up at a critical rotor speed. Blades with modified torsional and flapwise stiffness are also investigated. A flutter analysis is often part of the stability investigations for new blades but is normally carried out with engineering models that do not include the influence of unsteady trailed vorticity. Including this influence results in a slightly increased safety margin against classical flutter in all simulated cases.

Pirrung, Georg R.; Madsen, Helge Aa; Kim, Taeseong

2014-06-01